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• Managing software projects - advice needed

  - by Callum

  I work for a large government department as part of an IT team that manages and develops websites as well as stand alone web applications. We’re running in to problems somewhere in the SDLC that don’t rear their ugly head until time and budget are starting to run out. We try to be “Agile” (software specifications are not as thorough as possible, clients have direct access to the developers any time they want) and we are also in a reasonably peculiar position in that we are not allowed to make profit from the services we provide. We only service the divisions within our government department, and can only charge for the time and effort we actually put in to a project. So if we deliver a project that we have over-quoted on, we will only invoice for the actual time spent. Our software specifications are not as thorough as they could be, but they always include at a minimum: Wireframe mockups for every form view A data dictionary of all field inputs Descriptions of any business rules that affect the system Descriptions of the outputs I’m new to software management, but I’ve overseen enough software projects now to know that as soon as users start observing demos of the system, they start making a huge amount of requests like “Can we add a few more fields to this report.. can we redesign the look of this interface.. can we send an email at this part of the workflow.. can we take this button off this view.. can we make this function redirect to a different screen.. can we change some text on this screen… can we create a special account where someone can log in and get access to X… this report takes too long to run can it be optimised.. can we remove this step in the workflow… there’s got to be a better image we can put here…” etc etc etc. Some changes are tiny and can be implemented reasonably quickly.. but there could be up to 50-100 or so of such requests during the course of the SDLC. Other change requests are what clients claim they “just assumed would be part of the system” even if not explicitly spelled out in the spec. We are having a lot of difficulty managing this process. With no experienced software project managers in our team, we need to come up with a better way to both internally identify whether work being requested is “out of spec”, and be able to communicate this to a client in such a manner that they can understand why what they are asking for is “extra” work. We need a way to track this work and be transparent with it. In the spirit of Agile development where we are not spec'ing software systems in to the ground and back again before development begins, and bearing in mind that clients have access to any developer any time they want it, I am looking for some tips and pointers from experienced software project managers on how to handle this sort of "scope creep" problem, in tracking it, being transparent with it, and communicating it to clients such that they understand it. Happy to clarify anything as needed. I really appreciate anyone who takes the time to offer some advice. Thanks.

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• Oracle at ARM TechCon

  - by Tori Wieldt

  ARM TechCon is a technical conference for hardware and software engineers, Oct. 30-Nov 1 in Santa Clara, California. Days two and three of the conference will be geared towards systems designers and software developers, those interested in building ARM processor-based modules, boards, and systems. It will cover all of the hardware and software, tools, ranging from low-power design, networking and connectivity, open source software, and security. Oracle is a sponsor of ARM TechCon, and will present three Java sessions and a hands-on-lab:  "Do You Like Coffee with Your Dessert? Java and the Raspberry Pi" - The Raspberry Pi, an ARM-powered single board computer running a full Linux distro off an SD card has caused a huge wave of interest among developers. This session looks at how Java can be used on a device such as this. Using Java SE for embedded devices and a port of JavaFX, the presentation includes a variety of demonstrations of what the Raspberry Pi is capable of. The Raspberry Pi also provides GPIO line access, and the session covers how this can be used from Java applications. Prepare to be amazed at what this tiny board can do. (Angela Caicedo, Java Evangelist) "Modernizing the Explosion of Advanced Microcontrollers with Embedded Java" - This session explains why Oracle Java ME Embedded is the right choice for building small, connected, and intelligent embedded solutions, such as industrial control applications, smart sensing, wireless connectivity, e-health, or general machine-to-machine (M2M) functionality---extending your business to new areas, driving efficiency, and reducing cost. The new Oracle Java ME Embedded product brings the benefits of Java technology to microcontroller platforms. It is a full-featured, complete, compliant software runtime with value-add features targeted to the embedded space and has the ability to interface with additional hardware components, remote manageability, and over-the-air software updates. It is accompanied by a feature-rich set of tools free of charge. (Fareed Suliman, Java Product Manager) "Embedded Java in Smart Energy and Healthcare" - This session covers embedded Java products and technologies that enable smart and connect devices in the Smart Energy and Healthcare/Medical industries. (speaker Kevin Lee) "Java SE Embedded Development on ARM Made Easy" - This Hands-on Lab aims to show that developers already familiar with the Java develop/debug/deploy lifecycle can apply those same skills to develop Java applications, using Java SE Embedded, on embedded devices. (speaker Jim Connors) In the Oracle booth #603, you can see the following demos: Industry Solutions with JavaThis exhibit consists of a number of industry solutions and how they can be powered by Java technology deployed on embedded systems.  Examples in consumer devices, home gateways, mobile health, smart energy, industrial control, and tablets all powered by applications running on the Java platform are shown.  Some of the solutions demonstrate the ability of Java to connect intelligent devices at the edge of the network to the datacenter or the cloud as a total end-to-end platform.Java in M2M with QualcommThis station will exhibit a new M2M solutions platform co-developed by Oracle and Qualcomm that enables wireless communications for embedded smart devices powered by Java, and share the types of industry solutions that are possible.  In addition, a new platform for wearable devices based on the ARM Cortex M3 platform is exhibited.Why Java for Embedded?Demonstration platforms will show how traditional development environments, tools, and Java programming skills can be used to create applications for embedded devices.  The advantages that Java provides because of  the runtime's abstraction of software from hardware, modularity and scalability, security, and application portability and manageability are shared with attendees. Drop by and see why Java is an optimal applications platform for embedded systems.

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• Blind As a Bat in Multi-Monitor Hell &ndash; Free Program Inside!

  - by ToStringTheory

  If you know me personally, then you probably know that I am going blind thanks to a rare genetic eye disease.  My eye disease has already been a huge detriment to my eyesight.  One of the big things to suffer is my ability to see small things moving fast right in front of me.  On a multi-monitor setup, this makes finding the cursor absolute hell. The Problem I’ll keep this short, as I’ve basically already told you what the problem is.  On my three monitor development computer, I am constantly losing the mouse during the day.  I had used the Microsoft accessibility mousefinder (press CTRL, and it pings around the mouse).  The problem with this is, there is only an effect around 50-100 PX around the mouse, and it is a very light gray, almost unnoticeable.. For someone like me, if I am not looking at the monitor when I click the CTRL button, I have to click it multiple times and dart my eyes back and forth in a futile attempt to catch a glimpse of the action…  I had tried other cursor finders, but none I liked… The Solution So what’s a guy to do when he doesn’t like his options?  MAKE A NEW OPTION…  What else should we as developers do, am I right?  So, I went ahead and made a mousefinder of my own, with 6 separate settings to change the effect.  I am releasing it here for anyone else that may also have problems finding their mouse at times. Some of its features include: Multiple options to change to achieve the exact effect you want. If your mouse moves while it is honing in, it will hone in on its current position. Many times, I would press the button and move my mouse at the same time, and many times, the mouse happened to be at a screen edge, so I would miss it. This program will restart its animation on a new screen if the mouse changes its screen while playing. Tested on Windows 7 x64 Stylish color changing from green to red. Deployed as a ClickOnce, so easy to remove if you don't like it. Press Right CTRL to trigger effect Application lives in notification area so that you can easily reach configuration or close it. To get it to run on startup, copy its application shortcut from its startmenu directory to the “Startup” folder in your startmenu. Conclusion I understand if you don’t download this…  You don’t know me and I don’t know you.  I can only say that I have honestly NOT added any virus’ or malware to the package. Yeah, I know it’s weird Download: ‘ToString(theory) Mousefinder.zip’ CRC32: EEBCE300 MD5: 0394DA581BE6F3371B5BA11A8B24BC91 SHA-1: 2080C4930A2E7D98B81787BB5E19BB24E118991C Finally, if you do use this application - please leave a comment, or email me and tell me what you think of it. Encounter a bug or hashes no longer match? I want to know that too! <warning type=”BadPun”>Now, stop messing around and start mousing around!</warning>

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• Internet of Things Becoming Reality

  - by kristin.jellison

  The Internet of Things is not just on the radar—it’s becoming a reality. A globally connected continuum of devices and objects will unleash untold possibilities for businesses and the people they touch. But the “things” are only a small part of a much larger, integrated architecture. A great example of this comes from the healthcare industry. Imagine an expectant mother who needs to watch her blood pressure. She lives in a mountain village 100 miles away from medical attention. Luckily, she can use a small “wearable” device to monitor her status and wirelessly transmit the information to a healthcare hub in her village. Now, say the healthcare hub identifies that the expectant mother’s blood pressure is dangerously high. It sends a real-time alert to the patient’s wearable device, advising her to contact her doctor. It also pushes an alert with the patient’s historical data to the doctor’s tablet PC. He inserts a smart security card into the tablet to verify his identity. This ensures that only the right people have access to the patient’s data. Then, comparing the new data with the patient’s medical history, the doctor decides she needs urgent medical attention. GPS tracking devices on ambulances in the field identify and dispatch the closest one available. An alert also goes to the closest hospital with the necessary facilities. It sends real-time information on her condition directly from the ambulance. So when she arrives, they already have a treatment plan in place to ensure she gets the right care. The Internet of Things makes a huge difference for the patient. She receives personalized and responsive healthcare. But this technology also helps the businesses involved. The healthcare provider achieves a competitive advantage in its services. The hospital benefits from cost savings through more accurate treatment and better application of services. All of this, in turn, translates into savings on insurance claims. This is an ideal scenario for the Internet of Things—when all the devices integrate easily and when the relevant organizations have all the right systems in place. But in reality, that can be difficult to achieve. Core design principles are required to make the whole system work. Open standards allow these systems to talk to each other. Integrated security protects personal, financial, commercial and regulatory information. A reliable and highly available systems infrastructure is necessary to keep these systems running 24/7. If this system were just made up of separate components, it would be prohibitively complex and expensive for almost any organization. The solution is integration, and Oracle is leading the way. We’re developing converged solutions, not just from device to datacenter, but across devices, utilizing the Java platform, and through data acquisition and management, integration, analytics, security and decision-making. The Internet of Things (IoT) requires the predictable action and interaction of a potentially endless number of components. It’s in that convergence that the true value of the Internet of Things emerges. Partners who take the comprehensive view and choose to engage with the Internet of Things as a fully integrated platform stand to gain the most from the Internet of Things’ many opportunities. To discover what else Oracle is doing to connect the world, read about Oracle’s Internet of Things Platform. Learn how you can get involved as a partner by checking out the Oracle Java Knowledge Zone. Best regards, David Hicks

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• Removing occurrences of characters in a string

  - by DmainEvent

  I am reading this book, programming Interviews exposed by John Wiley and sons and in chapter 6 they are discussing removing all instances of characters in a src string using a removal string... so removeChars(string str, string remove) In there writeup they sey the steps to accomplish this are to have a boolean lookup array with all values initially set to false, then loop through each character in remove setting the corresponding value in the lookup array to true (note: this could also be a hash if the possible character set where huge like Unicode-16 or something like that or if str and remove are both relatively small... < 100 characters I suppose). You then iterate through the str with a source and destination index, copying each character only if its corresponding value in the lookup array is false... Which makes sense... I don't understand the code that they use however... They have for(src = 0; src < len; ++src){ flags[r[src]] == true; } which is turning the flag value at the remove string indexed at src to true... so if you start out with PLEASE HELP as your str and LEA as your remove you will be setting in your flag table at 0,1,2... t|t|t but after that you will get an out of bounds exception because r doesn't have have anything greater than 2 in it... even using there example you get an out of bounds exception... Am is there code example unworkable? Entire function string removeChars( string str, string remove ){ char[] s = str.toCharArray(); char[] r = remove.toCharArray(); bool[] flags = new bool[128]; // assumes ASCII! int len = s.Length; int src, dst; // Set flags for characters to be removed for( src = 0; src < len; ++src ){ flags[r[src]] = true; } src = 0; dst = 0; // Now loop through all the characters, // copying only if they aren’t flagged while( src < len ){ if( !flags[ (int)s[src] ] ){ s[dst++] = s[src]; } ++src; } return new string( s, 0, dst ); } as you can see, r comes from the remove string. So in my example the remove string has only a size of 3 while my str string has a size of 11. len is equal to the length of the str string. So it would be 11. How can I loop through the r string since it is only size 3? I haven't compiled the code so I can loop through it, but just looking at it I know it won't work. I am thinking they wanted to loop through the r string... in other words they got the length of the wrong string here.

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• The long road to bug-free software

  - by Tony Davis

  The past decade has seen a burgeoning interest in functional programming languages such as Haskell or, in the Microsoft world, F#. Though still on the periphery of mainstream programming, functional programming concepts are gradually seeping into the imperative C# language (for example, Lambda expressions have their root in functional programming). One of the more interesting concepts from functional programming languages is the use of formal methods, the lofty ideal behind which is bug-free software. The idea is that we write a specification that describes exactly how our function (say) should behave. We then prove that our function conforms to it, and in doing so have proved beyond any doubt that it is free from bugs. All programmers already use one form of specification, specifically their programming language's type system. If a value has a specific type then, in a type-safe language, the compiler guarantees that value cannot be an instance of a different type. Many extensions to existing type systems, such as generics in Java and .NET, extend the range of programs that can be type-checked. Unfortunately, type systems can only prevent some bugs. To take a classic problem of retrieving an index value from an array, since the type system doesn't specify the length of the array, the compiler has no way of knowing that a request for the "value of index 4" from an array of only two elements is "unsafe". We restore safety via exception handling, but the ideal type system will prevent us from doing anything that is unsafe in the first place and this is where we start to borrow ideas from a language such as Haskell, with its concept of "dependent types". If the type of an array includes its length, we can ensure that any index accesses into the array are valid. The problem is that we now need to carry around the length of arrays and the values of indices throughout our code so that it can be type-checked. In general, writing the specification to prove a positive property, even for a problem very amenable to specification, such as a simple sorting algorithm, turns out to be very hard and the specification will be different for every program. Extend this to writing a specification for, say, Microsoft Word and we can see that the specification would end up being no simpler, and therefore no less buggy, than the implementation. Fortunately, it is easier to write a specification that proves that a program doesn't have certain, specific and undesirable properties, such as infinite loops or accesses to the wrong bit of memory. If we can write the specifications to prove that a program is immune to such problems, we could reuse them in many places. The problem is the lack of specification "provers" that can do this without a lot of manual intervention (i.e. hints from the programmer). All this might feel a very long way off, but computing power and our understanding of the theory of "provers" advances quickly, and Microsoft is doing some of it already. Via their Terminator research project they have started to prove that their device drivers will always terminate, and in so doing have suddenly eliminated a vast range of possible bugs. This is a huge step forward from saying, "we've tested it lots and it seems fine". What do you think? What might be good targets for specification and verification? SQL could be one: the cost of a bug in SQL Server is quite high given how many important systems rely on it, so there's a good incentive to eliminate bugs, even at high initial cost. [Many thanks to Mike Williamson for guidance and useful conversations during the writing of this piece] Cheers, Tony.

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• The best computer ever

  - by Jeff

  (This is a repost from my personal blog… wow… I need to write more technical stuff!) About three years and three months ago, I bought a 17" MacBook Pro, and it turned out to be the best computer I've ever owned. You might think that every computer with better specs is automatically better than the last, but that hasn't been my experience. My first one was a Sony, back in the Pentium III days, and it cost an astonishing $2,500. That was even more ridiculous in 1999 dollars. It had a dial-up modem, and a CD-ROM, built-in! It may have even played DVD's. A few years later I bought an HP, and it ended up being a pile of shit. The power connector inside came loose from the board, and on occasion would even short. In 2005, I bought a Dell, and it wasn't bad. It had a really high resolution screen (complete with dead pixels, a problem in those days), and it was the first laptop I felt I could do real work on. When 2006 rolled around, Apple started making computers with Intel CPU's, and I bought the very first one the week it came out. I used Boot Camp to run Windows. I still have it in its box somewhere, and I used it for three years. The current 17" was new in 2009. The goodness was largely rooted in having a big screen with lots of dots. This computer has been the source of hundreds of blog posts, tens of thousands of lines of code, video and photo editing, and of course, a whole lot of Web surfing. It connected to corpnet at Microsoft, WiFi in Hawaii and has presented many a deck. It has traveled with me tens of thousands of miles. Last year, I put a solid state drive in it, and it was like getting a new computer. I can boot up a Windows 7 VM in about 19 seconds. Having 8 gigs of RAM has always been fantastic. Everything about it has been fast and fun. When new, the battery (when not using VM's) could get as much as 10 hours. I can still do 7 without much trouble. After 460 charge cycles, the battery health is still between 85 and 90%. The only real negative has been the size and weight. It's only an inch thick, but naturally it's pretty big with a 17" screen. You don't get battery life like that without a huge battery, either, so it's heavy. It was never a deal breaker, but sometimes a long haul across a large airport, you know you're carrying it. Today, Apple announced a new, thinner and lighter 15" laptop, with twice the RAM and CPU cores, and four times the screen resolution. It basically handles my size and weight issues while retaining the resolution, and it still costs less than my 17" did. So I ordered one. Three years is an excellent run, but I kind of budgeted for a new workhorse this year anyway. So if you're interested in a 17" MacBook Pro with a Core 2 Duo 2.66 GHz CPU, 8 gigs of RAM and a 320 gig hard drive (sorry, I'm keeping the SSD), I have one to sell. They've apparently discontinued the 17", which is going to piss off the video community. It's in excellent condition, with a few minor scratches, but I take care of my stuff.

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• The Social Content Conundrum

  - by Mike Stiles

  Here’s the social content conundrum: people who are not entertainers are being asked to entertain. Despite a world of skilled MBAs, marketing savants, technological innovators, analysts, social strategists and consultants, every development in social for brands keeps boomeranging right back to the same unavoidable truth. Success hinges on having content creators who know how to entertain the target audience. You can’t make this all about business-processes. You can’t make this all about technology, though data is critical and helps inform content. This is about having human beings who know the audience, know what they’d love to see, and can create the magic that will draw and hold them. Since showing up in the News Feed is critical for exposition and engagement, and since social ads primarily serve to amplify content that’s performing well, I’m comfortable saying content creators are becoming exponentially recruited and valued. They will no longer be commodities. They’ll be your stars. Social has fundamentally changed the relationship between brand and consumer. No longer can the customer be told to sit down, shut up, and listen to our ads. It’s now all about what consumers are willing to watch or read. Their patience for subjecting themselves to material they aren’t interested in is waning. Therefore, brands must now be producers of entertainment and information content, not merely placers of ads within someone else’s content. Social has given you a huge stage, with an audience sitting out there waiting to see what you’re going to do. What are you putting on that stage? For most corporate environments, entertaining is alien. It’s risky and subjective. Most operate around two foundational principles: control and fear. To entertain and inform with branded content, some control has to go. You control the product. Past that, control is being transferred into the hands of the consumer. The “fear first” culture also has to yield. If you strive to never make waves, you will move absolutely nothing. Because most corporations don’t house entertainers, they must be found then trusted. They’re usually a little weird. The ideas they’ll bring may seem “out there.” But like any business professional, they’ve gone through the training and experiences that make them uniquely good at what they do, even if you don’t quite understand them. It’s okay. It’s what the audience thinks that matters. Get it right, and you’ll be generating one ambassador after another who’s proud to be identified with the brand and will regularly consume and share your content. Entertainment entities are able to shape our culture and succeed beyond their wildest dreams by being beholden to one thing…what the public likes and wants. When brands put the same emphasis on crowd-pleasing content, they too will enjoy brand fame the likes of which they’ve never seen. The stage is yours. Now get out there and go for that applause.

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• Using HTML5 Today part 3&ndash; Using Polyfills

  - by Steve Albers

  Shims helps when adding semantic tags to older IE browsers, but there is a huge range of other new HTML5 features that having varying support on browsers.  Polyfills are JavaScript code and/or browser plug-ins that can provide older or less featured browsers with API support.  The best polyfills will detect the whether the current browser has native support, and only adds the functionality if necessary.  The Douglas Crockford JSON2.js library is an example of this approach: if the browser already supports the JSON object, nothing changes.  If JSON is not available, the library adds a JSON property in the global object. This approach provides some big benefits: It lets you add great new HTML5 features to your web sites sooner. It lets the developer focus on writing to the up-and-coming standard rather than proprietary APIs. Where most one-off legacy code fixes tends to break down over time, well done polyfills will stop executing over time (as customer browsers natively support the feature) meaning polyfill code may not need to be tested against new browsers since they will execute the native methods instead. Your should also remember that Polyfills represent an entirely separate code path (and sometimes plug-in) that requires testing for support.  Also Polyfills tend to run on older browsers, which often have slower JavaScript performance.  As a result you might find that performance on older browsers is not comparable. When looking for Polyfills you can start by checking the Modernizr GitHub wiki or the HTML5 Please site. For an example of a polyfill consider a page that writes a few geometric shapes on a <canvas> <script src="jquery-1.7.1.min.js"><script> <script> $(document).ready(function () { drawCanvas(); }); function drawCanvas() { var context = $("canvas")[0].getContext('2d'); //background context.fillStyle = "#8B0000"; context.fillRect(5, 5, 300, 100); // emptybox context.strokeStyle = "#B0C4DE"; context.lineWidth = 4; context.strokeRect(20, 15, 80, 80); // circle context.arc(160, 55, 40, 0, Math.PI * 2, false); context.fillStyle = "#4B0082"; context.fill(); </script>   The result is a simple static canvas with a box & a circle:   …to enable this functionality on a pre-canvas browser we can find a polyfill.  A check on html5please.com references  FlashCanvas.  Pull down the zip and extract the files (flashcanvas.js, flash10canvas.swf, etc) to a directory on your site.  Then based on the documentation you need to add a single line to your original HTML file: <!--[if lt IE 9]><script src="flashcanvas.js"></script><![endif]—> …and you have canvas functionality!  The IE conditional comments ensure that the library is only loaded in browsers where it is useful, improving page load & processing time. Like all Polyfills, you should test to verify the functionality matches your expectations across browsers you need to support.  For instance the Flash Canvas home page advertises 70% support of HTML5 Canvas spec tests.

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• Red Meat's Music is Rare - and Well Done

  - by Oracle OpenWorld Blog Team

  By Karen Shamban The blogger has questions; San Francisco-based country band Red Meat has answers. Although we forgot to ask how they got their band name, dang it. Read on and enjoy the honesty and insight. Q. What do you like best about performing in front of a live audience?A. Probably just having fun and entertaining the audience. We've been together for almost two decades, and in that time we've played for crowds of five people, and for crowds of more than 15,000. Both are equally important to us, and just as fun. We turn Jill and Smelley loose on the between-songs repartee, and let the songs shine through. On the best night, we feed on the audience's love and vice-versa. It's emotional vampirism of the best sort. [Blogger's note: now that whole "red meat" thing is starting to make sense ...] Q. Do you prefer smaller, intimate venues or larger, louder ones? Why?A. We love both. Whether it's a chance to connect with a small room or huge audience, we always try to hit 'em between the eyes! Q. What about your fans surprises you?A. Since we've been together for so long, we're pretty much on our third generation of fans now. We're excited that the Bakersfield sound has that same effect on the new, younger fans as it did on the punk rockers that we played to 20 years ago. And we still see them at our shows too! Q. What about your live act surprises your fans?A. For people who haven't seen Red Meat before, they may be dragged to a show thinking they don't like country music. But they're surprised to hear it done in a way that excites them so much. We get a lot of first-timers coming up to us after a performance and asking, "Wait, THAT'S what country music can sound like?" Q. There are going to be a lot of technical people (you could call them geeks) in the Oracle crowd - what are they going to love about your performance?A. Just what everyone loves about a Red Meat show - the chance to drink beer, dance, get rowdy, and have a great time. Q. Have you been on tour recently? If so, what do you like about touring, and what do you dislike?A. Actually, we're going to be coming off the road immediately into the Oracle OpenWorld Music Festival, having just played some Texas dates. On tour, we love playing for fans who don't get to see us as often as our California fans do. And food. Most of our conversations in the van center around food. Q. Ever think about playing another kind of music? If so, what, and why?A. Our tastes and influences in the band run all over the place. Obviously we love the Bakersfield artists - Buck Owens, Merle Haggard, Dwight Yoakam - but we love other types of roots music as well, along with the Beatles, NRBQ, MC5, punk/new wave, and countless bar bands that we've had the privilege of playing with through the years. But as far as playing a different kind of music as Red Meat? Nah. We love what we're doing. Q. What are the top three things people should know about your music?A1. Country music, done right, has unlimited soul.A2. Red Meat is a modern band, playing original material, with a great debt to the Bakersfield sound of Buck Owens and Merle Haggard.A3. It's FUN. More details on the Festival and the band: Oracle OpenWorld Music Festival Red Meat

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• PCI Encryption Key Management

  - by Unicorn Bob

  (Full disclosure: I'm already an active participant here and at StackOverflow, but for reasons that should hopefully be obvious, I'm choosing to ask this particular question anonymously). I currently work for a small software shop that produces software that's sold commercially to manage small- to mid-size business in a couple of fairly specialized industries. Because these industries are customer-facing, a large portion of the software is related to storing and managing customer information. In particular, the storage (and securing) of customer credit card information. With that, of course, comes PCI compliance. To make a long story short, I'm left with a couple of questions about why certain things were done the way they were, and I'm unfortunately without much of a resource at the moment. This is a very small shop (I report directly to the owner, as does the only other full-time employee), and the owner doesn't have an answer to these questions, and the previous developer is...err...unavailable. Issue 1: Periodic Re-encryption As of now, the software prompts the user to do a wholesale re-encryption of all of the sensitive information in the database (basically credit card numbers and user passwords) if either of these conditions is true: There are any NON-encrypted pieces of sensitive information in the database (added through a manual database statement instead of through the business object, for example). This should not happen during the ordinary use of the software. The current key has been in use for more than a particular period of time. I believe it's 12 months, but I'm not certain of that. The point here is that the key "expires". This is my first foray into commercial solution development that deals with PCI, so I am unfortunately uneducated on the practices involved. Is there some aspect of PCI compliance that mandates (or even just strongly recommends) periodic key updating? This isn't a huge issue for me other than I don't currently have a good explanation to give to end users if they ask why they are being prompted to run it. Question 1: Is the concept of key expiration standard, and, if so, is that simply industry-standard or an element of PCI? Issue 2: Key Storage Here's my real issue...the encryption key is stored in the database, just obfuscated. The key is padded on the left and right with a few garbage bytes and some bits are twiddled, but fundamentally there's nothing stopping an enterprising person from examining our (dotfuscated) code, determining the pattern used to turn the stored key into the real key, then using that key to run amok. This seems like a horrible practice to me, but I want to make sure that this isn't just one of those "grin and bear it" practices that people in this industry have taken to. I have developed an alternative approach that would prevent such an attack, but I'm just looking for a sanity check here. Question 2: Is this method of key storage--namely storing the key in the database using an obfuscation method that exists in client code--normal or crazy? Believe me, I know that free advice is worth every penny that I've paid for it, nobody here is an attorney (or at least isn't offering legal advice), caveat emptor, etc. etc., but I'm looking for any input that you all can provide. Thank you in advance!

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• Migrating VB6 to HTML5 is not a fiction - Customer success story

  - by Webgui

  All of you VB developers in the present or past would probably find it hard to believe that the old VB code can be migrated and modernized into the latest .NET based HTML5 without having to rewrite the application. But we have been working on such tools for the past couple of years and already have several real world applications that were fully 'transposed' from VB6. The solution is called Instant CloudMove and its main tool is called the TranspositionStudio. It is a unique solution that relies on the concept of transposition. Transposition comes from mathematics and music and refers to exchanging elements while everything else remains the same or moving an element as is from one environment to another. This means that we are taking the source code and put it in a modern technological environment with relatively few adjustments.The concept is based on a set of Mapping Expressions which are basically links between an element in the source environment and one in the target environment that has the same functionality. About 95% of the code is usually mapped out-of-the-box and the rest is handled with easy-to-use mapping tools designed for Visual Studio developers providing them with a familiar environment and concepts for completing the mapping and allowing them to extend and customize existing mapping expressions. The solution is also based on a circular workflow that enables developers to make any changes as required until the result is satisfying.As opposed to existing migration solutions that offer automation are usually a “black box” to the user, the transposition concept enables full visibility, flexibility and control over the code and process at all times allowing to also add/change functionalities or upgrade the UI within the process and tools.This is exactly the case with our customer’s aging VB6 PMS (Property Management System) which needed a technological update as well as a design refresh. The decision was to move the VB6 application which had about 1 million lines of code into the latest web technology. Since the application was initially written 13 years ago and had many upgrades since the code must be very patchy and includes unused sections. As a result, the company Mihshuv Group considered rewriting the entire application in Java since it already had the knowledge. Rewrite would allow starting with a clean slate and designing functionality, database architecture, UI without any constraints. On the other hand, rewrite entitles a long and detailed specification work as well as a thorough QA and this translates into a long project with high risk and costs.So the company looked for a migration solution as an alternative; the research lead to Gizmox and after examining the technology it was decided to perform a hybrid project which would include an automatic transposition of the core of the VB6 application (200,000 lines of code) while they redesigning the UI, adding new functionality, deleting unused code and rewriting about 140 reports with Crystal Reports will be done manually using Visual WebGui development tools.The migration part of the project was completed in 65 days by 3 developers from Mihshuv Group guided by Gizmox migration experts while the rewrite and UI upgrade tasks took about the same. So in only a few months period Mihshuv Group generated an up-to-date product, written in the latest Web technology with modern, friendly UI and improved functionality. Guest selection screen of the original VB6 PMS Guest selection screen on the new web–based PMS Compared to the initial plan to rewrite the entire application in Java, the hybrid migration/rewrite approach taken by Mihshuv Group using Gizmox technology proved as a great decision. In terms of time and cost there were substantial savings; from a project that was priced for at least a year (without taking into account the huge risk and uncertainty) it became a few months project only. More about this and other customer stories can be found here

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• What's new in Servlet 3.1 ? - Java EE 7 moving forward

  - by arungupta

  Servlet 3.0 was released as part of Java EE 6 and made huge changes focused at ease-of-use. The idea was to leverage the latest language features such as annotations and generics and modernize how Servlets can be written. The web.xml was made as optional as possible. Servet 3.1 (JSR 340), scheduled to be part of Java EE 7, is an incremental release focusing on couple of key features and some clarifications in the specification. The main features of Servlet 3.1 are explained below: Non-blocking I/O - Servlet 3.0 allowed asynchronous request processing but only traditional I/O was permitted. This can restrict scalability of your applications. Non-blocking I/O allow to build scalable applications. TOTD #188 provide more details about how non-blocking I/O can be done using Servlet 3.1. HTTP protocol upgrade mechanism - Section 14.42 in the HTTP 1.1 specification (RFC 2616) defines an upgrade mechanism that allows to transition from HTTP 1.1 to some other, incompatible protocol. The capabilities and nature of the application-layer communication after the protocol change is entirely dependent upon the new protocol chosen. After an upgrade is negotiated between the client and the server, the subsequent requests use the new chosen protocol for message exchanges. A typical example is how WebSocket protocol is upgraded from HTTP as described in Opening Handshake section of RFC 6455. The decision to upgrade is made in Servlet.service method. This is achieved by adding a new method: HttpServletRequest.upgrade and two new interfaces: javax.servlet.http.HttpUpgradeHandler and javax.servlet.http.WebConnection. TyrusHttpUpgradeHandler shows how WebSocket protocol upgrade is done in Tyrus (Reference Implementation for Java API for WebSocket). Security enhancements Applying run-as security roles to #init and #destroy methods Session fixation attack by adding HttpServletRequest.changeSessionId and a new interface HttpSessionIdListener. You can listen for any session id changes using these methods. Default security semantic for non-specified HTTP method in <security-constraint> Clarifying the semantics if a parameter is specified in the URI and payload Miscellaneous ServletResponse.reset clears any data that exists in the buffer as well as the status code, headers. In addition, Servlet 3.1 will also clears the state of calling getServletOutputStream or getWriter. ServletResponse.setCharacterEncoding: Sets the character encoding (MIME charset) of the response being sent to the client, for example, to UTF-8. Relative protocol URL can be specified in HttpServletResponse.sendRedirect. This will allow a URL to be specified without a scheme. That means instead of specifying "http://anotherhost.com/foo/bar.jsp" as a redirect address, "//anotherhost.com/foo/bar.jsp" can be specified. In this case the scheme of the corresponding request will be used. Clarification in HttpServletRequest.getPart and .getParts without multipart configuration. Clarification that ServletContainerInitializer is independent of metadata-complete and is instantiated per web application. A complete replay of What's New in Servlet 3.1: An Overview from JavaOne 2012 can be seen here (click on CON6793_mp4_6793_001 in Media). Each feature will be added to the JSR subject to EG approval. You can share your feedback to [email protected]. Here are some more references for you: Servlet 3.1 Public Review Candidate Downloads Servlet 3.1 PR Candidate Spec Servlet 3.1 PR Candidate Javadocs Servlet Specification Project JSR Expert Group Discussion Archive Java EE 7 Specification Status Several features have already been integrated in GlassFish 4 Promoted Builds. Have you tried any of them ? Here are some other Java EE 7 primers published so far: Concurrency Utilities for Java EE (JSR 236) Collaborative Whiteboard using WebSocket in GlassFish 4 (TOTD #189) Non-blocking I/O using Servlet 3.1 (TOTD #188) What's New in EJB 3.2 ? JPA 2.1 Schema Generation (TOTD #187) WebSocket Applications using Java (JSR 356) Jersey 2 in GlassFish 4 (TOTD #182) WebSocket and Java EE 7 (TOTD #181) Java API for JSON Processing (JSR 353) JMS 2.0 Early Draft (JSR 343) And of course, more on their way! Do you want to see any particular one first ?

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• College Ratings via the Federal Government

  - by user9147039

  A few weeks back you might remember news about a higher education rating system proposal from the Obama administration. As I've discussed previously, political and stakeholder pressures to improve outcomes and increase transparency are stronger than ever before. The executive branch proposal is intended to make progress in this area. Quoting from the proposal itself, "The ratings will be based upon such measures as: Access, such as percentage of students receiving Pell grants; Affordability, such as average tuition, scholarships, and loan debt; and Outcomes, such as graduation and transfer rates, graduate earnings, and advanced degrees of college graduates.” This is going to be quite complex, to say the least. Most notably, higher ed is not monolithic. From community and other 2-year colleges, to small private 4-year, to professional schools, to large public research institutions…the many walks of higher ed life are, well, many. Designing a ratings system that doesn't wind up with lots of unintended consequences and collateral damage will be difficult. At best you would end up potentially tarnishing the reputation of certain institutions that were actually performing well against the metrics and outcome measures that make sense in their "context" of education. At worst you could spend a lot of time and resources designing a system that would lose credibility with its "customers". A lot of institutions I work with already have in place systems like the one described above. They are tracking completion rates, completion timeframes, transfers to other institutions, job placement, and salary information. As I talk to these institutions there are several constants worth noting: • Deciding on which metrics to measure is complicated. While employment and salary data are relatively easy to track, qualitative measures are more difficult. How do you quantify the benefit to someone who studies in one field that may not compensate him or her as well as another field but that provides huge personal fulfillment and reward is a difficult measure to quantify? • The data is available but the systems to transform the data into actual information that can be used in meaningful ways are not. Too often in higher ed information is siloed. As such, much of the data that need to be a part of a comprehensive system sit in multiple organizations, oftentimes outside the reach of core IT. • Politics and culture are big barriers. One of the areas that my team and I spend a lot of time talking about with higher ed institutions all over the world is the imperative to optimize for student success. This, like the tracking of the students’ achievement after graduation, requires a level or organizational capacity that does not currently exist. The primary barrier is the culture of "data islands" in higher ed, and the need for leadership to drive out the divisions between departments, schools, colleges, etc. and institute academy-wide analytics and data stewardship initiatives that will enable student success. • Data quality is a very big issue. So many disparate systems exist (some on premise, some "in the cloud") that keep data about "persons" using different means to identify them. Establishing a single source of truth about an individual and his or her data is difficult without some type of data quality policy and tools. Good tools actually exist but are seldom leveraged. Don't misunderstand - I think it's a great idea to drive additional transparency and accountability into the system of higher education. And not just at home, but globally. Students and parents need access to key data to make informed, responsible choices. The tools exist to not only enable this kind of information to be shared but to capture the very metrics stakeholders care most about and in a way that makes sense in the context of a given institution's "place" in the overall higher ed panoply.

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• Optimal Data Structure for our own API

  - by vermiculus

  I'm in the early stages of writing an Emacs major mode for the Stack Exchange network; if you use Emacs regularly, this will benefit you in the end. In order to minimize the number of calls made to Stack Exchange's API (capped at 10000 per IP per day) and to just be a generally responsible citizen, I want to cache the information I receive from the network and store it in memory, waiting to be accessed again. I'm really stuck as to what data structure to store this information in. Obviously, it is going to be a list. However, as with any data structure, the choice must be determined by what data is being stored and what how it will be accessed. What, I would like to be able to store all of this information in a single symbol such as stack-api/cache. So, without further ado, stack-api/cache is a list of conses keyed by last update: `(<csite> <csite> <csite>) where <csite> would be (1362501715 . <site>) At this point, all we've done is define a simple association list. Of course, we must go deeper. Each <site> is a list of the API parameter (unique) followed by a list questions: `("codereview" <cquestion> <cquestion> <cquestion>) Each <cquestion> is, you guessed it, a cons of questions with their last update time: `(1362501715 <question>) (1362501720 . <question>) <question> is a cons of a question structure and a list of answers (again, consed with their last update time): `(<question-structure> <canswer> <canswer> <canswer> and ` `(1362501715 . <answer-structure>) This data structure is likely most accurately described as a tree, but I don't know if there's a better way to do this considering the language, Emacs Lisp (which isn't all that different from the Lisp you know and love at all). The explicit conses are likely unnecessary, but it helps my brain wrap around it better. I'm pretty sure a <csite>, for example, would just turn into (<epoch-time> <api-param> <cquestion> <cquestion> ...) Concerns: Does storing data in a potentially huge structure like this have any performance trade-offs for the system? I would like to avoid storing extraneous data, but I've done what I could and I don't think the dataset is that large in the first place (for normal use) since it's all just human-readable text in reasonable proportion. (I'm planning on culling old data using the times at the head of the list; each inherits its last-update time from its children and so-on down the tree. To what extent this cull should take place: I'm not sure.) Does storing data like this have any performance trade-offs for that which must use it? That is, will set and retrieve operations suffer from the size of the list? Do you have any other suggestions as to what a better structure might look like?

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• F# Objects &ndash; Integration with the other .Net Languages &ndash; Part 2

  - by MarkPearl

  So in part one of my posting I covered the real basics of object creation. Today I will hopefully dig a little deeper… My expert F# book brings up an interesting point – properties in F# are just syntactic sugar for method calls. This makes sense… for instance assume I had the following object with the property exposed called Firstname. type Person(Firstname : string, Lastname : string) = member v.Firstname = Firstname I could extend the Firstname property with the following code and everything would be hunky dory… type Person(Firstname : string, Lastname : string) = member v.Firstname = Console.WriteLine("Side Effect") Firstname   All that this would do is each time I use the property Firstname, I would see the side effect printed to the screen saying “Side Effect”. Member methods have a very similar look & feel to properties, in fact the only difference really is that you declare that parameters are being passed in. type Person(Firstname : string, Lastname : string) = member v.FullName(middleName) = Firstname + " " + middleName + " " + Lastname   In the code above, FullName requires the parameter middleName, and if viewed from another project in C# would show as a method and not a property. Precomputation Optimizations Okay, so something that is obvious once you think of it but that poses an interesting side effect of mutable value holders is pre-computation of results. All it is, is a slight difference in code but can result in quite a huge saving in performance. Basically pre-computation means you would not need to compute a value every time a method is called – but could perform the computation at the creation of the object (I hope I have got it right). In a way I battle to differentiate this from lazy evaluation but I will show an example to explain the principle. Let me try and show an example to illustrate the principle… assume the following F# module namespace myNamespace open System module myMod = let Add val1 val2 = Console.WriteLine("Compute") val1 + val2 type MathPrecompute(val1 : int, val2 : int) = let precomputedsum = Add val1 val2 member v.Sum = precomputedsum type MathNormalCompute(val1 : int, val2 : int) = member v.Sum = Add val1 val2 Now assume you have a C# console app that makes use of the objects with code similar to the following… using System; using myNamespace; namespace CSharpTest { class Program { static void Main(string[] args) { Console.WriteLine("Constructing Objects"); var myObj1 = new myMod.MathNormalCompute(10, 11); var myObj2 = new myMod.MathPrecompute(10, 11); Console.WriteLine(""); Console.WriteLine("Normal Compute Sum..."); Console.WriteLine(myObj1.Sum); Console.WriteLine(myObj1.Sum); Console.WriteLine(myObj1.Sum); Console.WriteLine(""); Console.WriteLine("Pre Compute Sum..."); Console.WriteLine(myObj2.Sum); Console.WriteLine(myObj2.Sum); Console.WriteLine(myObj2.Sum); Console.ReadKey(); } } } The output when running the console application would be as follows…. You will notice with the normal compute object that the system would call the Add function every time the method was called. With the Precompute object it only called the compute method when the object was created. Subtle, but something that could lead to major performance benefits. So… this post has gone off in a slight tangent but still related to F# objects.

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• SSMS Tools Pack 2.7 is released. New website, improved licensing and features.

  - by Mladen Prajdic

  New website Nice, isn't it? Cleaner, simpler, better looking and more modern. If you have any suggestions for further improvements I'd be glad to hear them. Simpler licensing With SSMS tools Pack 2.7 the licensing is finally where it should be. It is now based on the activate/deactivate model. This way you can move a license from machine to machine with simple deactivation on one and reactivation on another machine. Much better, no? Because of very good feedback I have added an option for 6 machines and lowered the 4 machines option to 3 machines. This should make it much simpler for you to choose the right option for yourself. Improved features Version 2.5.3 was already extremely stable and 2.7 continues with that tradition. Because of that I could fully focus on features and why 3.0 will rock even more that 2.7! ;) In version 2.7 I have addressed quite a few improvements you were requesting for a while now. SQL History This is probably the biggest time saver out there, therefore it's only fair it gets a few important updates. If you have an existing .sql file opened, the Window Content History now saves your code to that existing file and also makes a backup in the SQL History log default location. Search is still done through the SQL History log but the Tab Sessions Restore opens your existing .sql file. This way you don't have to remember to save your existing files by yourself anymore. A bug when you couldn't search properly if you copied the log files to a new location was fixed. Unfortunately this removed the option to filter a search with the time component. The smallest search interval is now one day. The SSMS Tools Pack now remembers the visibility of the Current Window History window when you exit SSMS. SQL Snippets You can now set the position of the cursor in your snippets by placing {C} somewhere in your snippet. It's a small improvement but can be a huge time saver since you don't have to move through the snippet to the desired location anymore. Run script on multiple databases Database choices can now be saved with a name and then loaded again next time. You can also choose to run the script in a new window for each chosen database. Search through grid results You can now go previous/next search result with the Prev/Next control inside the search window. This is extremely useful if you have a large resultset. IT saves you the scrolling. CRUD generator Four new variables have been added: |CurrentDate| writes current date in format yyyy-MM-dd to your script |CurrentTime| writes current time in 24h format HH:mm:ss to your script |CurrentWinUser| writes current Windows logged on user to your script |CurrentSqlUser| writes current SQL logged on login to your script This was actually quite a requested feature so if you have any other ideas for extra variables, do let me know. That's about it. I hope you're going to enjoy this version as much as the previous ones. Have fun!

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• MySQL Server 5.6 default my.cnf and my.ini

  - by user12626240

  We've introduced a default my.cnf / my.ini file for MySQL Server that you can now see in the 5.6.8 release candidate: # For advice on how to change settings please see # http://dev.mysql.com/doc/refman/5.6/en/server-configuration-defaults.html [mysqld] # Remove leading # and set to the amount of RAM for the most important data # cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%. # innodb_buffer_pool_size = 128M   # Remove leading # to turn on a very important data integrity option: logging # changes to the binary log between backups. # log_bin   # These are commonly set, remove the # and set as required. # basedir = ..... # datadir = ..... # port = ..... # socket = ..... # server_id = .....   # Remove leading # to set options mainly useful for reporting servers. # The server defaults are faster for transactions and fast SELECTs. # Adjust sizes as needed, experiment to find the optimal values. # join_buffer_size = 128M # sort_buffer_size = 2M # read_rnd_buffer_size = 2M   sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES    There is also a template file called my-default.cnf or my-default.ini that has these lines near the start: # *** DO NOT EDIT THIS FILE. It's a template which will be copied to the # *** default location during install, and will be replaced if you # *** upgrade to a newer version of MySQL.   On Linux systems, the mysql_install_db command will copy the template file to the final location, where the server will read and use the file, removing the extra three lines. On Windows, the installer will create extra settings based on the answers you gave during installation. Neither will overwrite an existing my.cnf or my.ini file. The only initially active setting here is to change the value of  sql_mode from the server default of NO_ENGINE_SUBSTITUTION to NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES. This strict mode changes warnings for some non-standard behaviour into errors. This can cause applications which rely on the non-standard things, like dates that aren't valid, to lose data. If we had just changed the server default, the new setting would affect all servers that lack an explicit sql_mode setting, including those where strict mode is harmful. So we did it in the default file instead because that will only affect new server installations. You should expect that in our next version after 5.6, the server default will include STRICT_TRANS_TABLES. Our Windows installer and some of our connectors already use STRICT_TRANS_TABLES by default. Strict has been our preferred setting for many years and it is good to see some development platforms are using it. If you need the old behaviour, just remove the STRICT_TRANS_TABLES setting. If you do this, please also ask your application provider to make it unnecessary. They can do that by setting the session sql_mode setting in their own connections, so the rest of the applications using the server don't have to have an undesirable default. We've kept this file as small as possible because we found that our old files were too big and confused people. We've also now removed the old my-huge and related example files. One key part of this is the link to the documentation, where we will provide an introduction to some key settings. We'd like to hear your feedback on settings that will benefit most users or are most important to call out for existing users. Please do that by commenting here or if you prefer by adding comments to this bug report.

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• Is the Leptonica implementation of 'Modified Median Cut' not using the median at all?

  - by TheCodeJunkie

  I'm playing around a bit with image processing and decided to read up on how color quantization worked and after a bit of reading I found the Modified Median Cut Quantization algorithm. I've been reading the code of the C implementation in Leptonica library and came across something I thought was a bit odd. Now I want to stress that I am far from an expert in this area, not am I a math-head, so I am predicting that this all comes down to me not understanding all of it and not that the implementation of the algorithm is wrong at all. The algorithm states that the vbox should be split along the lagest axis and that it should be split using the following logic The largest axis is divided by locating the bin with the median pixel (by population), selecting the longer side, and dividing in the center of that side. We could have simply put the bin with the median pixel in the shorter side, but in the early stages of subdivision, this tends to put low density clusters (that are not considered in the subdivision) in the same vbox as part of a high density cluster that will outvote it in median vbox color, even with future median-based subdivisions. The algorithm used here is particularly important in early subdivisions, and 3is useful for giving visible but low population color clusters their own vbox. This has little effect on the subdivision of high density clusters, which ultimately will have roughly equal population in their vboxes. For the sake of the argument, let's assume that we have a vbox that we are in the process of splitting and that the red axis is the largest. In the Leptonica algorithm, on line 01297, the code appears to do the following Iterate over all the possible green and blue variations of the red color For each iteration it adds to the total number of pixels (population) it's found along the red axis For each red color it sum up the population of the current red and the previous ones, thus storing an accumulated value, for each red note: when I say 'red' I mean each point along the axis that is covered by the iteration, the actual color may not be red but contains a certain amount of red So for the sake of illustration, assume we have 9 "bins" along the red axis and that they have the following populations 4 8 20 16 1 9 12 8 8 After the iteration of all red bins, the partialsum array will contain the following count for the bins mentioned above 4 12 32 48 49 58 70 78 86 And total would have a value of 86 Once that's done it's time to perform the actual median cut and for the red axis this is performed on line 01346 It iterates over bins and check they accumulated sum. And here's the part that throws me of from the description of the algorithm. It looks for the first bin that has a value that is greater than total/2 Wouldn't total/2 mean that it is looking for a bin that has a value that is greater than the average value and not the median ? The median for the above bins would be 49 The use of 43 or 49 could potentially have a huge impact on how the boxes are split, even though the algorithm then proceeds by moving to the center of the larger side of where the matched value was.. Another thing that puzzles me a bit is that the paper specified that the bin with the median value should be located, but does not mention how to proceed if there are an even number of bins.. the median would be the result of (a+b)/2 and it's not guaranteed that any of the bins contains that population count. So this is what makes me thing that there are some approximations going on that are negligible because of how the split actually takes part at the center of the larger side of the selected bin. Sorry if it got a bit long winded, but I wanted to be as thoroughas I could because it's been driving me nuts for a couple of days now ;)

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• The long road to bug-free software

  - by Tony Davis

  The past decade has seen a burgeoning interest in functional programming languages such as Haskell or, in the Microsoft world, F#. Though still on the periphery of mainstream programming, functional programming concepts are gradually seeping into the imperative C# language (for example, Lambda expressions have their root in functional programming). One of the more interesting concepts from functional programming languages is the use of formal methods, the lofty ideal behind which is bug-free software. The idea is that we write a specification that describes exactly how our function (say) should behave. We then prove that our function conforms to it, and in doing so have proved beyond any doubt that it is free from bugs. All programmers already use one form of specification, specifically their programming language's type system. If a value has a specific type then, in a type-safe language, the compiler guarantees that value cannot be an instance of a different type. Many extensions to existing type systems, such as generics in Java and .NET, extend the range of programs that can be type-checked. Unfortunately, type systems can only prevent some bugs. To take a classic problem of retrieving an index value from an array, since the type system doesn't specify the length of the array, the compiler has no way of knowing that a request for the "value of index 4" from an array of only two elements is "unsafe". We restore safety via exception handling, but the ideal type system will prevent us from doing anything that is unsafe in the first place and this is where we start to borrow ideas from a language such as Haskell, with its concept of "dependent types". If the type of an array includes its length, we can ensure that any index accesses into the array are valid. The problem is that we now need to carry around the length of arrays and the values of indices throughout our code so that it can be type-checked. In general, writing the specification to prove a positive property, even for a problem very amenable to specification, such as a simple sorting algorithm, turns out to be very hard and the specification will be different for every program. Extend this to writing a specification for, say, Microsoft Word and we can see that the specification would end up being no simpler, and therefore no less buggy, than the implementation. Fortunately, it is easier to write a specification that proves that a program doesn't have certain, specific and undesirable properties, such as infinite loops or accesses to the wrong bit of memory. If we can write the specifications to prove that a program is immune to such problems, we could reuse them in many places. The problem is the lack of specification "provers" that can do this without a lot of manual intervention (i.e. hints from the programmer). All this might feel a very long way off, but computing power and our understanding of the theory of "provers" advances quickly, and Microsoft is doing some of it already. Via their Terminator research project they have started to prove that their device drivers will always terminate, and in so doing have suddenly eliminated a vast range of possible bugs. This is a huge step forward from saying, "we've tested it lots and it seems fine". What do you think? What might be good targets for specification and verification? SQL could be one: the cost of a bug in SQL Server is quite high given how many important systems rely on it, so there's a good incentive to eliminate bugs, even at high initial cost. [Many thanks to Mike Williamson for guidance and useful conversations during the writing of this piece] Cheers, Tony.

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• EPPM Is a Must-Have Capability as Global Energy and Power Industries Eye US$38 Trillion in New Investments

  - by Melissa Centurio Lopes

  Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} “The process manufacturing industry is facing an unprecedented challenge: from now until 2035, cumulative worldwide investments of US$38 trillion will be required for drilling, power generation, and other energy projects,” Iain Graham, director of energy and process manufacturing for Oracle’s Primavera, said in a recent webcast. He adds that process manufacturing organizations such as oil and gas, utilities, and chemicals must manage this level of investment in an environment of constrained capital markets, erratic supply and demand, aging infrastructure, heightened regulations, and declining global skills. In the following interview, Graham explains how the right enterprise project portfolio management (EPPM) technology can help the industry meet these imperatives. Q: Why is EPPM so important for today’s process manufacturers? A: If the industry invests US$38 trillion without proper cost controls in place, a huge amount of resources will be put at risk, especially when it comes to cost overruns that may occur in large capital projects. Process manufacturing companies must not only control costs, but also monitor all the various contractors that will be involved in each project. If you’re not managing your own workers and all the interdependencies among the different contractors, then you’ve got problems. Q: What else should process manufacturers look for? A: It’s also important that an EPPM solution has the ability to manage more than just capital projects. For example, it’s best to manage maintenance and capital projects in the same system. Say you’re due to install a new transformer in a power station as part of a capital project, but routine maintenance in that area of the facility is scheduled for that morning. The lack of coordination could lead to unforeseen delays. There are also IT considerations that impact capital projects, such as adding servers and network cable for a control system in a power station. What organizations need is a true EPPM system that’s not just for capital projects, maintenance, or IT activities, but instead an enterprisewide solution that provides visibility into all types of projects. Read the complete Q&A here and discover the practical framework for successfully managing this massive capital spending.

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• Making user input/math on data fast, unlike excel type programs

  - by proGrammar

  I'm creating a research platform solely for myself to do some research on data. Programs like excel are terribly slow for me so I'm trying to come up with another solution. Originally I used excel. A1 was the cell that contained the data and all other cells in use calculated something on A1, or on other cells, that all could be in the end traced to A1. A1 was like an element of an array, I then I incremented it to go through all my data. This was way too slow. So the only other option I found originally was to hand code in c# the calculations inside a loop. Then I simply recompiled each time I changed my math. This was terribly slow to do and I had to order everything correctly so things would update correctly (dependencies). I could have also used events, but hand coding events for each cell like calculation would also be very slow. Next I created an application to read Excel and to perfectly imitate it. Which is what I now use. Basically I write formulas onto a fraction of my data to get live results inside excel. Then my program reads excel, writes another c# program, compiles it, and runs that program which runs my excel created formulas through a lot more data a whole lot faster. The advantage being my application dependency sorts everything (or I could use events) so I don't have to (like excel does) And of course the speed. But now its not a single application anymore. Instead its 2 applications, one which only reads my formulas and writes another program. The other one being the result which only lives for a short while before I do other runs through my data with different formulas / settings. So I can't see multiple results at one time without introducing even more programs like a database or at least having the 2 applications talking to each other. My idea was to have a dll that would be written, compiled, loaded, and unloaded again and again. So a self-updating program, sort of. But apparently that's not possible without another appdomain which means data has to be marshaled to be moved between the appdomains. Which would slow things down, not for summaries, but for other stuff I need to do with all my data. I'm also forgetting to mention a huge problem with restarting an application again and again which is having to reload ALL my data into memory again and again. But its still a whole lot faster than excel. I'm really super puzzled as to what people do when they want to research data fast. I'm completely unable to have a program accept user input and having it fast. My understanding is that it would have to do things like excel which is to evaluate strings again and again. So my only option is to repeatedly compile applications. Do I have a correct understanding on computer science? I've only just began programming, and didn't think I would have to learn much to do some simple math on data. My understanding is its either compiling my user defined stuff to a program or evaluating them from a string or something stupid again and again. And my only option is to probably switch operating systems or something to be able to have a program compile and run itself without stopping (writing/compiling dll, loading dll to program, unloading, and repeating). Can someone give me some idea on how computers work? Is anything better possible? Like a running program, that can accept user input and compile it and then unload it later? I mean heck operating systems dont need to be RESTARTED with every change to user input. What is this the cave man days? Sorry, it's just so super frustrating not knowing what one can do, and can't do. If only I could understand and learn this stuff fast enough.

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• Slide 2d Vector to destination over a period of time

  - by SchautDollar

  I am making a library of GUI controls for games I make with XNA. I am currently developing the library as I make a game so I can test the features and find errors/bugs and hopefully smash them right away. My current issue is on a slide feature I want to implement for my base class that all controls inherit. My goal is to get the control to slide to a specified point over a specified amount of time. Here is the #region containing the code #region Slide private bool sliding; private Vector2 endPoint; private float slideTimeLeft; private float speed; private bool wasEnabled; private Vector2 slideDirection; private float slideDistance; public void Slide(Vector2 startPoint, Vector2 endPoint, float slideTime) { this.location = startPoint; Slide(endPoint,slideTime); } public void Slide(Vector2 endPoint, float slideTime) { this.wasEnabled = this.enabled; this.enabled = false; this.sliding = true; Vector2 tempLength = endPoint - this.location; this.slideDistance = tempLength.Length(); //Was this.slideDistance = (float)Math.Sqrt(tempLength.LengthSquared()); this.speed = slideTime / this.slideDistance; this.endPoint = endPoint; this.slideTimeLeft = slideTime; } private void UpdateSlide(GameTime gameTime) { if (this.sliding) { this.slideTimeLeft -= gameTime.ElapsedGameTime.Milliseconds; if (this.slideTimeLeft >= 0 ) { if ((this.endPoint-this.location).Length() != 0){//Was if (this.endPoint.LengthSquared() > 0 || this.location.LengthSquared() > 0) { this.slideDirection = Vector2.Normalize(this.endPoint - this.location); } this.location += this.slideDirection * speed * gameTime.ElapsedGameTime.Milliseconds;//This is where I believe the issue is, but I'm not sure. It seems right to me... (Even though it doesn't work) } else { this.enabled = this.wasEnabled; this.location = this.endPoint;//After time, the controls position will get set to be the endpoint. this.sliding = false; } } } #endregion this.location is the location of the control elsewhere defined in the class. I have looked at this blog as a huge reference and have googled around quite and have looked on many forums but can't find anything that shows how to implement it. Please and Thanks for your time! EDIT: I have switched this line "this.location += this.slideDirection * speed * gameTime.ElapsedGameTime.Milliseconds;" several times to see what it does. My issue is getting the control to smoothly move to the end location. It moves after the time has expired, but It doesn't move other then that except flash in my face. EDIT2: I have used the first slide method with 3 parameters and it works except it doesn't do it in a period of time and once it gets to its destination, it starts moving randomly towards the previous location and the end location.

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• Core Data migration problem: "Persistent store migration failed, missing source managed object model

  - by John Gallagher

  The Background A Cocoa Non Document Core Data project with two Managed Object Models. Model 1 stays the same. Model 2 has changed, so I want to migrate the store. I've created a new version by Design Data Model Add Model Version in Xcode. The difference between versions is a single relationship that's been changed from to a one to many. I've made my changes to the model, then saved. I've made a new Mapping Model that has the old model as a source and new model as a destination. I've ensured all Mapping Models and Data Models and are being compiled and all are copied to the Resource folder of my app bundle. I've switched on migrations by passing in a dictionary with the NSMigratePersistentStoresAutomaticallyOption key as [NSNumber numberWithBool:YES] when adding the Persistent Store. Rather than merging all models in the bundle, I've specified the two models I want to use (model 1 and the new version of model 2) and merged them using modelByMergingModels: The Problem No matter what I do to migrate, I get the error message: "Persistent store migration failed, missing source managed object model." What I've Tried I clean after every single build. I've tried various combinations of having only the model I'm migrating to in Resources, being compiled, or both. Since the error message implies it can't find the source model for my migration, I've tried having every version of the model in both the Resources folder and being compiled. I've made sure I'm not making a really basic error by switching back to the original version of my data model. The app runs fine. I've deleted the Mapping Model and the new version of the model, cleaned, then recreated both. I've tried making a different change in the new model - deleting an entity instead. I'm at my wits end. I can't help but think I've made a huge mistake somewhere that I'm not seeing. Any ideas?

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• View all ntext column text in SQL Server Management Studio for SQL CE database

  - by Dave

  I often want to do a "quick check" of the value of a large text column in SQL Server Management Studio (SSMS). The maximum number of characters that SSMS will let you view, in grid results mode, is 65535. (It is even less in text results mode.) Sometimes I need to see something beyond that range. Using SQL Server 2005 databases, I often used the trick of converting it to XML, because SSMS lets you view much larger amounts of text that way: SELECT CONVERT(xml, MyCol) FROM MyTable WHERE ... But now I am using SQL CE, and there is no Xml data type. There is still a "Maximum Characters Retreived XML" value under Options; I suppose this is useful when connecting to other data sources. I know I can just get the full value by running a little console app or something, but is there a way within SSMS to see the entire ntext column value? [Edit] OK, this didn't get much attention the first time around (18 views?!). It's not a huge concern, but maybe I'm just obsessed with it. There has to be some good way around this, doesn't there? So a modest bounty is active. What I am willing to accept as answers, in order from best-to-worst: A solution that works just as easy as the XML trick in SQL CE. That is, a single function (convert, cast, etc.) that does the job. A not-too-invasive way to hack SSMS to get it to display more text in the results. An equivalent SQL query (perhaps something that creatively uses SUBSTRING and generates multiple ad-hoc columns??) to see the results. The solution should work with nvarchar and ntext columns of any length in SQL CE from SSMS. Any ideas?

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