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• help with matlab and Discrete Fourier transform

  - by user504363

  Hi all I have previous experience with Matlab, but the problem that I face some problems in apply a problem in (DSP : Digital signal processing) which is not my study field, but I must finish that problems in days to complete my project. all i want is help me with method and steps of solving this problem in matlab and then I can write the code with myself. the problem is about the signal x(t) = exp(-a*t); 1) what's the Discrete Fourier transform of the sampled signal with sample rate fs 2) if a=1 and fs =1 , plot the amplitude spectrum of sampled signal 3) fix the sampling frequency at fs = 1(hz) [what's it mean ?] and plot the magnitude of the Fourier Transform of the sampled signal at various values of a thanks

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• Signal amplitude against time (java)

  - by wsr74ws84

  Hi everyone , I'm racking my brain in order to solve a knotty problem (at least for me) While playing an audio file (using java) I want the signal amplitude to be displayed against time. I mean I'd like to implement a small panel showing a sort of oscilloscope .(SPECTRUM ANALYZER) The audio signal should be viewed in the time domain (vertical axis is amplitude and the horizontal axis is time) Does anyone know how to do it? Is there a good tutorial I can rely on? Since I know vwry little about java , I wish someone could help me . Thanks in advance.

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• Changing the tint of a bitmap while preserving the overall brightness

  - by MusiGenesis

  I'm trying to write a function that will let me red-shift or blue-shift a bitmap while preserving the overall brightness of the image. Basically, a fully red-shifted bitmap would have the same brightness as the original but be thoroughly red-tinted (i.e. the G and B values would be equal for all pixels). Same for blue-tinting (but with R and G equal). The degree of spectrum shifting needs to vary from 0 to 1. Thanks in advance.

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• What is your favorite colorscheme FOR PROGRAMMING in Vim?

  - by ThomasGHenry

  I think this is a relevant question for programmers and I'd like to hear other people's answers because some syntax highlighting color schemes are better on the eyes than others. This can affect productivity as much as ergonomic keyboards or anything else on here. It's about comfort and productivity. So, I'm curious. Do you find some color schemes better adapted for some languages over others? At the other end of the spectrum, I think coding without syntax highlight is awful and slow going. Does anyone work better like this? Thanks! EDIT: so we'll try it as a community wiki. Similar Question

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• Is Python Interpreted or Compiled?

  - by crodjer

  This is just a wondering I had while reading about interpreted and compiled languages. Ruby is no doubt an interpreted language, since source code is compiled by an interpreter at the point of execution. On the contrary C is a compiled language, as one have to compile the source code first according to the machine and then execute. This results is much faster execution. Now coming to Python: A python code (somefile.py) when imported creates a file (somefile.pyc) in the same directory. Let us say the import is done in a python shell or django module. After the import I change the code a bit and execute the imported functions again to find that it is still running the old code. This suggests that *.pyc files are compiled python files similar to executable created after compilation of a C file, though I can't execute *.pyc file directly. When the python file (somefile.py) is executed directly ( ./somefile.py or python somefile.py ) no .pyc file is created and the code is executed as is indicating interpreted behavior. These suggest that a python code is compiled every time it is imported in a new process to crate a .pyc while it is interpreted when directly executed. So which type of language should I consider it as? Interpreted or Compiled? And how does its efficiency compare to interpreted and compiled languages? According to wiki's Interpreted Languages page it is listed as a language compiled to Virtual Machine Code, what is meant by that? Update Looking at the answers it seems that there cannot be a perfect answer to my questions. Languages are not only interpreted or only compiled, but there is a spectrum of possibilities between interpreting and compiling. From the answers by aufather, mipadi, Lenny222, ykombinator, comments and wiki I found out that in python's major implementations it is compiled to bytecode, which is a highly compressed and optimized representation and is machine code for a virtual machine, which is implemented not in hardware, but in the bytecode interpreter. Also the the languages are not interpreted or compiled, but rather language implementations either interpret or compile code. I also found out about Just in time compilation As far as execution speed is concerned the various benchmarks cannot be perfect and depend on context and the task which is being performed. Please tell if I am wrong in my interpretations.

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• Defining Discovery: Core Concepts

  - by Joe Lamantia

  Discovery tools have had a referencable working definition since at least 2001, when Ben Shneiderman published 'Inventing Discovery Tools: Combining Information Visualization with Data Mining'.  Dr. Shneiderman suggested the combination of the two distinct fields of data mining and information visualization could manifest as new category of tools for discovery, an understanding that remains essentially unaltered over ten years later.  An industry analyst report titled Visual Discovery Tools: Market Segmentation and Product Positioning from March of this year, for example, reads, "Visual discovery tools are designed for visual data exploration, analysis and lightweight data mining." Tools should follow from the activities people undertake (a foundational tenet of activity centered design), however, and Dr. Shneiderman does not in fact describe or define discovery activity or capability. As I read it, discovery is assumed to be the implied sum of the separate fields of visualization and data mining as they were then understood.  As a working definition that catalyzes a field of product prototyping, it's adequate in the short term.  In the long term, it makes the boundaries of discovery both derived and temporary, and leaves a substantial gap in the landscape of core concepts around discovery, making consensus on the nature of most aspects of discovery difficult or impossible to reach.  I think this definitional gap is a major reason that discovery is still an ambiguous product landscape. To help close that gap, I'm suggesting a few definitions of four core aspects of discovery.  These come out of our sustained research into discovery needs and practices, and have the goal of clarifying the relationship between discvoery and other analytical categories.  They are suggested, but should be internally coherent and consistent.   Discovery activity is: "Purposeful sense making activity that intends to arrive at new insights and understanding through exploration and analysis (and for these we have specific defintions as well) of all types and sources of data." Discovery capability is: "The ability of people and organizations to purposefully realize valuable insights that address the full spectrum of business questions and problems by engaging effectively with all types and sources of data." Discovery tools: "Enhance individual and organizational ability to realize novel insights by augmenting and accelerating human sense making to allow engagement with all types of data at all useful scales." Discovery environments: "Enable organizations to undertake effective discovery efforts for all business purposes and perspectives, in an empirical and cooperative fashion." Note: applicability to a world of Big data is assumed - thus the refs to all scales / types / sources - rather than stated explicitly.  I like that Big Data doesn't have to be written into this core set of definitions, b/c I think it's a transitional label - the new version of Web 2.0 - and goes away over time. References and Resources: Inventing Discovery Tools Visual Discovery Tools: Market Segmentation and Product Positioning Logic versus usage: the case for activity-centered design A Taxonomy of Enterprise Search and Discovery

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• NoSQL is not about object databases

  - by Bertrand Le Roy

  NoSQL as a movement is an interesting beast. I kinda like that it’s negatively defined (I happen to belong myself to at least one other such a-community). It’s not in its roots about proposing one specific new silver bullet to kill an old problem. it’s about challenging the consensus. Actually, blindly and systematically replacing relational databases with object databases would just replace one set of issues with another. No, the point is to recognize that relational databases are not a universal answer -although they have been used as one for so long- and recognize instead that there’s a whole spectrum of data storage solutions out there. Why is it so hard to recognize, by the way? You are already using some of those other data storage solutions every day. Let me cite a few: The file system Active Directory XML / JSON documents The Web e-mail Logs Excel files EXIF blobs in your photos Relational databases And yes, object databases It’s just a fact of modern life. Notice by the way that most of the data that you use every day is unstructured and thus mostly unsuitable for relational storage. It really is more a matter of recognizing it: you are already doing NoSQL. So what happens when for any reason you need to simultaneously query two or more of these heterogeneous data stores? Well, you build an index of sorts combining them, and that’s what you query instead. Of course, there’s not much distance to travel from that to realizing that querying is better done when completely separated from storage. So why am I writing about this today? Well, that’s something I’ve been giving lots of thought, on and off, over the last ten years. When I built my first CMS all that time ago, one of the main problems my customers were facing was to manage and make sense of the mountain of unstructured data that was constituting most of their business. The central entity of that system was the file system because we were dealing with lots of Word documents, PDFs, OCR’d articles, photos and static web pages. We could have stored all that in SQL Server. It would have worked. Ew. I’m so glad we didn’t. Today, I’m working on Orchard (another CMS ;). It’s a pretty young project but already one of the questions we get the most is how to integrate existing data. One of the ideas I’ll be trying hard to sell to the rest of the team in the next few months is to completely split the querying from the storage. Not only does this provide great opportunities for performance optimizations, it gives you homogeneous access to heterogeneous and existing data sources. For free.

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• Analysis Services Tabular books #ssas #tabular

  - by Marco Russo (SQLBI)

  Many people are looking for books about Analysis Services Tabular. Today there are two books available and they complement each other: Microsoft SQL Server 2012 Analysis Services: The BISM Tabular Model by Marco Russo, Alberto Ferrari and Chris Webb Applied Microsoft SQL Server 2012 Analysis Services: Tabular Modeling by Teo Lachev The book I wrote with Alberto and Chris is a complete guide to create tabular models and has a good coverage about DAX, including how to use it for enriching a semantic model with calculated columns and measures and how to use it for querying a Tabular model. In my experience, DAX as a query language is a very interesting option for custom analytical applications that requires a fast calculation engine, or simply for standard reports running in Reporting Services and accessing a Tabular model. You can freely preview the table of content and read some excerpts from the book on Safari Books Online. The book is in printing and should be shipped within mid-July, so finally it will be very soon on the shelf of all the people already preordered it! The Teo Lachev’s book, covers the full spectrum of Tabular models provided by Microsoft: starting with self-service BI, you have users creating a model with PowerPivot for Excel, publishing it to PowerPivot for SharePoint and exploring data by using Power View; then, the PowerPivot for Excel model can be imported in a Tabular model and published in Analysis Services, adding more control on the model through row-level security and partitioning, for example. Teo’s book follows a step-by-step approach describing each feature that is very good for a beginner that is new to PowerPivot and/or to BISM Tabular. If you need to get the big picture and to start using the products that are part of the new Microsoft wave of BI products, the Teo’s book is for you. After you read the book from Teo, or if you already have a certain confidence with PowerPivot or BISM Tabular and you want to go deeper about internals, best practices, design patterns in just BISM Tabular, then our book is a suggested read: it contains several chapters about DAX, includes discussions about new opportunities in data model design offered by Tabular models, and also provides examples of optimizations you can obtain in DAX and best practices in data modeling and queries. It might seem strange that an author write a review of a book that might seem to compete with his one, but in reality these two books complement each other and are not alternatives. If you have any doubt, buy both: you will be not disappointed! Moreover, Amazon usually offers you a deal to buy three books, including the Visualizing Data with Microsoft Power View, another good choice for getting all the details about Power View.

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• links for 2011-02-09

  - by Bob Rhubart

  Tech Cast Live - Java and Oracle, One Year Later - February 15th 10AM PST (Oracle Technology Network Blog (aka TechBlog)) (tags: ping.fm) The impact of IT decisions on organizational culture - O'Reilly Radar "While I believe we recognize the limiting qualities of IT decisions, I'd suggest we've insufficiently studied the degree to which those decisions in aggregate can have a large influence on organizational culture." - Jonathan Reichental, Ph.D. (tags: ITgovernance organizationalculture enterprisearchitecture) Women "computers" of World War II - Boing Boing "Before it came to mean laptops, PCs, or even room-sized machines, "computer" was what you called a person who did mathematical calculations for a living. That job was vitally important during World War II. And, like many vital jobs on the homefront, it was turned over to women..." (tags: computers history worldwar2) InfoQ: Book Excerpt and Interview: 100 SOA Questions Asked and Answered A new "100 SOA Questions Asked and Answered " book by Kerrie Holley and Ali Arsanjani provides a deep insight into SOA covering a wide spectrum of topics from SOA basics to its business and organizational impact, to SOA methods and architecture to SOA future. InfoQ spoke with Kerrie Holley and Ali Arsanjani about their book. (tags: ping.fm) @myfear: GlassFish City - Another view onto your favorite application server Oracle ACE Director Markus Eisele runs GlassFish through CodeCity. (tags: oracle otn oracleace glassfish codecity) The Ron Batra Blog: Technology Whispers: Upcoming Presentations Oracle ACE Director Ron Batra shares details on upcoming presentations at OAUG events in the US and Dubai. (tags: oaug c11 oracle otn oracleace) Free ADF Training Event in the UK (Grant Ronald's Blog) Gobsmack survivor Grant Ronald with the details on an Oracle ADF training session he'll conduct on 11 May 2011 at the UK Oracle office in Reading. (tags: oracle otn adf) Java Spotlight Episode 16 - Richar Bair - The Java Spotlight Podcast The latest Java Spotlight podcast features an interview with Java Client Architect Richar Bair. (tags: oracle java podcast) Stewart Bryson: OBIEE 11g Migrations "[Rittman Mead's] Mark and Venkat have covered OBIEE migration methodologies in the past (see here, here and here), but I decided to throw my hat in the ring on the subject, as I had to develop a methodology for a client recently and wanted to share my experiences." - Stewart Bryson (tags: oracle otn obiee businessintelligence) Dr. Chris Harding: The golden thread of interoperability | Open Group Blog "There are so many things going on at every Conference by The Open Group that it is impossible to keep track of all of them, and this week’s Conference in San Diego, California, is no exception. The main themes are Cybersecurity, Enterprise Architecture, SOA and Cloud Computing." - Dr. Chris Harding (tags: entarch soa interoperability cloud) Marc Kelderman: OSB: Creating an Asynchronous / Fire-Forget WebService Call Creating a fire-and-forget call via OSB is simple, according to solution architect Marc Kelderman. "The trick is to send NO response back to the caller, only an HTTP response code, 200 or any other." (tags: oracle otn servicebus)

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• StreamInsight 1.0 Released

  - by Roman Schindlauer

  One piece in the set of products offered in SQL Server 2008 R2 that has generated a lot of buzz and interest during its CTP phase is StreamInsight, Microsoft’s platform for Complex Event Processing. Microsoft’s information platform vision provides enterprises with a “complete approach” to managing information assets, enabling all businesses to gain strategic value from information from the desktop to the datacenter to the cloud. And StreamInsight V1 is one essential piece in this spectrum. After more than a year of blood, sweat, tears, and insane amounts of coffee we are proud to release the first version of our Complex Event Processing Framework.   Those of you who have been following our Community Technology Previews (CTPs) throughout last year have already had the possibility to familiarize themselves with the product. Early feedback was not only incredibly positive, but also very constructive and strongly influenced the final feature set. Four notable increments over our last public CTP are: Count windows Non-occurrence detection (Anti-Join) Dynamic query composition at runtime Synchronize time across input streams Additionally, many smaller issues and bugs were addressed. A few APIs slightly changed with respect to the November CTP, but porting your application to RTM should not require a lot of effort.   Here are the (english) bits - choosing the evaluation license during setup lets you already play with this version. Before you install, make sure to uninstall any previous CTP version:   StreamInsight X86StreamInsight X64   Within a few days, we will update our product page and add download links and instructions there as well.   The StreamInsight documentation is provided through a help file as part of the installation as well as through Books Online on MSDN. We also invite you to visit the StreamInsight Blog and the StreamInsight Forum, which is a great place to discuss questions and issues with the community and the development team.   Regards,Roman Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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• Get to Know a Candidate (2 of 25): Merlin Miller&ndash;American Third Position Party

  - by Brian Lanham

  DISCLAIMER: This is not a post about “Romney” or “Obama”. This is not a post for whom I am voting. Information sourced for Wikipedia. Meet Merlin Miller of American Third Position Party In addition to being American Third Position Party nominee, Miller is an independent film maker.  He is a graduate of West Point and has commanded two units in the United States Army.  After military service he worked as an industrial engineering manager for Michelin Tire.  He learned about film making by earning an MFA from the University of Southern California. Mr. Miller is on the ballot in: CO, NJ, and TN. In the 2000’s, Miller began taking an increasingly paleoconservative political stance.  He claimed that Hollywood “ surreptitiously seeks to destroy our European-American heritage and our Christian-based traditional values, and replace them with values that debase these traditional values and elevate minorities as paragons of virtue and wisdom....Today’s motion pictures, in concert with other forms of mass media entertainment, are the greatest enemies to the well-being of our progeny and the future of our country.” Miller states that he "doesn't like" interracial marriage; however, he does not support outlawing interracial marriage, either.  Miller has denied being anti-Semitic, instead claiming that he merely opposes "favoritism" granted to Jews in the film industry.  He also opposes illegal immigration and what he refers to as "wide open borders" in the United States. The American Third Position Party (A3P) is a third positionist American political party which promotes white supremacy.  It was officially launched in January 2010 (although in November 2009 it filed papers to get on a ballot in California) partially to channel the right-wing populist resentment engendered by the financial crisis of 2007–2010 and the policies of the Obama administration and defines its principal mission as representing the political interests of white Americans. The party takes a strong stand against immigration and globalization, and strongly supports an anti-interventionist foreign policy. Although the party does not support labor unions, they do strongly support the labor rights of the American working class on a platform of placing American workers first over illegal immigrant workers and banning of overseas corporate relocation of American industry and technology Third Position or Third Alternative refers to a revolutionary nationalist political position that emphasizes its opposition to both communism and capitalism. Advocates of Third Position politics typically present themselves as "beyond left and right", instead claiming to syncretize radical ideas from both ends of the political spectrum Learn more about Merlin Miller and American Third Position Party on Wikipedia.

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• How can a solo programmer become a good team player?

  - by Nick

  I've been programming (obsessively) since I was 12. I am fairly knowledgeable across the spectrum of languages out there, from assembly, to C++, to Javascript, to Haskell, Lisp, and Qi. But all of my projects have been by myself. I got my degree in chemical engineering, not CS or computer engineering, but for the first time this fall I'll be working on a large programming project with other people, and I have no clue how to prepare. I've been using Windows all of my life, but this project is going to be very unix-y, so I purchased a Mac recently in the hopes of familiarizing myself with the environment. I was fortunate to participate in a hackathon with some friends this past year -- both CS majors -- and excitingly enough, we won. But I realized as I worked with them that their workflow was very different from mine. They used Git for version control. I had never used it at the time, but I've since learned all that I can about it. They also used a lot of frameworks and libraries. I had to learn what Rails was pretty much overnight for the hackathon (on the other hand, they didn't know what lexical scoping or closures were). All of our code worked well, but they didn't understand mine, and I didn't understand theirs. I hear references to things that real programmers do on a daily basis -- unit testing, code reviews, but I only have the vaguest sense of what these are. I normally don't have many bugs in my little projects, so I have never needed a bug tracking system or tests for them. And the last thing is that it takes me a long time to understand other people's code. Variable naming conventions (that vary with each new language) are difficult (__mzkwpSomRidicAbbrev), and I find the loose coupling difficult. That's not to say I don't loosely couple things -- I think I'm quite good at it for my own work, but when I download something like the Linux kernel or the Chromium source code to look at it, I spend hours trying to figure out how all of these oddly named directories and files connect. It's a programming sin to reinvent the wheel, but I often find it's just quicker to write up the functionality myself than to spend hours dissecting some library. Obviously, people who do this for a living don't have these problems, and I'll need to get to that point myself. Question: What are some steps that I can take to begin "integrating" with everyone else? Thanks!

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• SQL Saturday 43 (Redmond, WA) Review

  - by BuckWoody

  Last Saturday (June 12th) we held a “SQL Saturday” (more about those here) event in Redmond, Washington. The event was held at the Microsoft campus, at the Mixer in our new location called the “Commons”. This is a mall-like area that we have on campus, and the Mixer is a large building with lots of meeting rooms, so it made a perfect location for the event. There was a sign to find the parking, and once there they had a sign to show how to get to the building. Since it’s a secure facility, Greg Larsen and crew had a person manning the door so that even late arrivals could get in. We had about 400 sign up for the event, and a little over 300 attend (official numbers later). I think we would have had a lot more, but the sun was out – and you just can’t underestimate the effect of that here in the Pacific Northwest. We joke a lot about not seeing the sun much, but when a day like what we had on Saturday comes around, and on a weekend at that, you’d cancel your wedding to go outside to play in the sun. And your spouse would agree with you for doing it. We had some top-notch speakers, including Clifford Dibble and Kalen Delany. The food was great, we had multiple sponsors (including Confio who seems to be at all of these) and the attendees were from all over the professional spectrum, from developers to BI to DBA’s. Everyone I saw was very engaged, and when I visited room-to-room I saw almost no one in the halls – everyone was in the sessions. I also saw a much larger Microsoft presence this year, especially from Dan Jones’ team. I had a great turnout at my session, and yes, I was wearing an Oracle staff shirt. I did that because I wanted to show that the session I gave on “SQL Server for the Oracle DBA” was non-marketing – I couldn’t exactly bash Oracle wearing their colors! These events are amazing. I can’t emphasize enough how much I appreciate the volunteers and how much work they put into these events, and to you for coming. If you’re reading this and you haven’t attended one yet, definitely find out if there is one in your area – and if not, start one. It’s a lot of work, but it’s totally worth it.       Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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• How to become a good team player?

  - by Nick

  I've been programming (obsessively) since I was 12. I am fairly knowledgeable across the spectrum of languages out there, from assembly, to C++, to Javascript, to Haskell, Lisp, and Qi. But all of my projects have been by myself. I got my degree in chemical engineering, not CS or computer engineering, but for the first time this fall I'll be working on a large programming project with other people, and I have no clue how to prepare. I've been using Windows all of my life, but this project is going to be very unix-y, so I purchased a Mac recently in the hopes of familiarizing myself with the environment. I was fortunate to participate in a hackathon with some friends this past year -- both CS majors -- and excitingly enough, we won. But I realized as I worked with them that their workflow was very different from mine. They used Git for version control. I had never used it at the time, but I've since learned all that I can about it. They also used a lot of frameworks and libraries. I had to learn what Rails was pretty much overnight for the hackathon (on the other hand, they didn't know what lexical scoping or closures were). All of our code worked well, but they didn't understand mine, and I didn't understand theirs. I hear references to things that real programmers do on a daily basis -- unit testing, code reviews, but I only have the vaguest sense of what these are. I normally don't have many bugs in my little projects, so I have never needed a bug tracking system or tests for them. And the last thing is that it takes me a long time to understand other people's code. Variable naming conventions (that vary with each new language) are difficult (__mzkwpSomRidicAbbrev), and I find the loose coupling difficult. That's not to say I don't loosely couple things -- I think I'm quite good at it for my own work, but when I download something like the Linux kernel or the Chromium source code to look at it, I spend hours trying to figure out how all of these oddly named directories and files connect. It's a programming sin to reinvent the wheel, but I often find it's just quicker to write up the functionality myself than to spend hours dissecting some library. Obviously, people who do this for a living don't have these problems, and I'll need to get to that point myself. Question: What are some steps that I can take to begin "integrating" with everyone else? Thanks!

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• C-states and P-states : confounding factors for benchmarking

  - by Dave

  I was recently looking into a performance issue in the java.util.concurrent (JUC) fork-join pool framework related to particularly long latencies when trying to wake (unpark) threads in the pool. Eventually I tracked the issue down to the power & scaling governor and idle-state policies on x86. Briefly, P-states refer to the set of clock rates (speeds) at which a processor can run. C-states reflect the possible idle states. The deeper the C-state (higher numerical values) the less power the processor will draw, but the longer it takes the processor to respond and exit that sleep state on the next idle to non-idle transition. In some cases the latency can be worse than 100 microseconds. C0 is normal execution state, and P0 is "full speed" with higher Pn values reflecting reduced clock rates. C-states are P-states are orthogonal, although P-states only have meaning at C0. You could also think of the states as occupying a spectrum as follows : P0, P1, P2, Pn, C1, C2, ... Cn, where all the P-states are at C0. Our fork-join framework was calling unpark() to wake a thread from the pool, and that thread was being dispatched onto a processor at deep C-state, so we were observing rather impressive latencies between the time of the unpark and the time the thread actually resumed and was able to accept work. (I originally thought we were seeing situations where the wakee was preempting the waker, but that wasn't the case. I'll save that topic for a future blog entry). It's also worth pointing out that higher P-state values draw less power and there's usually some latency in ramping up the clock (P-states) in response to offered load. The issue of C-states and P-states isn't new and has been described at length elsewhere, but it may be new to Java programmers, adding a new confounding factor to benchmarking methodologies and procedures. To get stable results I'd recommend running at C0 and P0, particularly for server-side applications. As appropriate, disabling "turbo" mode may also be prudent. But it also makes sense to run with the system defaults to understand if your application exhibits any performance sensitivity to power management policies. The operating system power management sub-system typically control the P-state and C-states based on current and recent load. The scaling governor manages P-states. Operating systems often use adaptive policies that try to avoid deep C-states for some period if recent deep idle episodes proved to be very short and futile. This helps make the system more responsive under bursty or otherwise irregular load. But it also means the system is stateful and exhibits a memory effect, which can further complicate benchmarking. Forcing C0 + P0 should avoid this issue.

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• SQL Saturday 43 (Redmond, WA) Review

  - by BuckWoody

  Last Saturday (June 12th) we held a “SQL Saturday” (more about those here) event in Redmond, Washington. The event was held at the Microsoft campus, at the Mixer in our new location called the “Commons”. This is a mall-like area that we have on campus, and the Mixer is a large building with lots of meeting rooms, so it made a perfect location for the event. There was a sign to find the parking, and once there they had a sign to show how to get to the building. Since it’s a secure facility, Greg Larsen and crew had a person manning the door so that even late arrivals could get in. We had about 400 sign up for the event, and a little over 300 attend (official numbers later). I think we would have had a lot more, but the sun was out – and you just can’t underestimate the effect of that here in the Pacific Northwest. We joke a lot about not seeing the sun much, but when a day like what we had on Saturday comes around, and on a weekend at that, you’d cancel your wedding to go outside to play in the sun. And your spouse would agree with you for doing it. We had some top-notch speakers, including Clifford Dibble and Kalen Delany. The food was great, we had multiple sponsors (including Confio who seems to be at all of these) and the attendees were from all over the professional spectrum, from developers to BI to DBA’s. Everyone I saw was very engaged, and when I visited room-to-room I saw almost no one in the halls – everyone was in the sessions. I also saw a much larger Microsoft presence this year, especially from Dan Jones’ team. I had a great turnout at my session, and yes, I was wearing an Oracle staff shirt. I did that because I wanted to show that the session I gave on “SQL Server for the Oracle DBA” was non-marketing – I couldn’t exactly bash Oracle wearing their colors! These events are amazing. I can’t emphasize enough how much I appreciate the volunteers and how much work they put into these events, and to you for coming. If you’re reading this and you haven’t attended one yet, definitely find out if there is one in your area – and if not, start one. It’s a lot of work, but it’s totally worth it.       Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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• Why is my dual-boot Ubuntu partition showing up as a peripheral "root.disk"?

  - by Don

  I recently installed Ubuntu 12.04, which I had been booting from a usb key, as a dual-boot on my machine running Windows 7. From what I had read online while researching, I was prepared to have to shrink the Windows partition and all that. But I never had to - it really was just a few clicks here and there and it was installed. I'm still pretty confused about it, but whatever, it worked, and the two peacefully coexist on my machine, and I have broken things to fix before I worry about fixing unbroken things. So yesterday I got it in my head to look at my partitions (I was considering making an all new partition to install the Windows 8 Release Preview). What I saw confused me. Here's a screenshot of the disk utility. At this moment, there is nothing connected to my computer, and nothing in any of the optical drives/ports/card readers/etc. Can you help me figure out what's going on here? Don's Machine is, I believe, my Windows partition - that's the name I assigned my machine from Windows Explorer. PQSERVICE is from what I can find online also Windows, but having to do with backup. And SYSTEM REQUIRED, if I browse it in Ubuntu, is definitely something to do with booting, and I believe it is also Windows'. According to the sizes shown, those three together should use up my 500 GB HD. Then further down, as a "peripheral device", it lists that 31 GB disk. This is obviously my Ubuntu (Model:Linux Loop:root.disk), but why is it showing up as a peripheral? So, to sum up those questions and to add some more random ones I had: Why is Ubuntu showing up as a peripheral device? If the Windows sections take up all 500 GB, where does Ubuntu live? If I renamed the disk partitions, would my life become a nightmare (seriously - can I safely rename them)? Why didn't I have to resize the Windows partition in the first place? Would giving Ubuntu more space improve its performance (it hangs alot)? Is it possible to have a partition for each OS (Windows 7 & 8, Ubuntu), a partition for files, and a separate partition for backups? Is this towards the good or bad idea end of the spectrum? @Elfy, would that explain why it keeps hanging? I guess I'll backup my files, rip it out, and reinstall it correctly later on today.

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• Arçelik A.S. Uses Advanced Analytics to Improve Product Development

  - by Sylvie MacKenzie, PMP

  "Oracle’s Primavera P6 Enterprise Project Portfolio Management’s advanced analytics gives us better insight into the product development process by helping us to identify potential roadblocks.” – Iffet Iyigun Meydanli, Innovation and System Development Manager, R&D Center, Arçelik A.S. Founded in 1955, Arçelik A.S. is now the leading household appliance manufacturer in Turkey, and the third-largest household appliance company in Europe. It operates 14 production facilities in five countries (Turkey, Romania, Russia, China, and South Africa), with international sales and marketing offices in 20 countries. Additionally, the company manages 10 brands (Arçelik, Beko, Grundig, Blomberg, Elektrabregenz, Arctic, Leisure, Flavel, Defy, and Altus). The company has a household presence in more than 100 countries, including China and the United States. Arçelik’s Beko brand is among the top-10 household appliance brands in world, as a market leader for refrigerators, freezers, and washing machines in the United Kingdom. Arçelik implemented Oracle’s Primavera P6 Enterprise Project Portfolio Management for improved management of its design and manufacturing projects. With the solution, Arelik has improved its research and development (R&D) with the ability to evaluate technology risks when planning its projects. Also, it is now more easy to make plans for several locations, monitor all resources, and plan for future projects.  Challenges Improve monitoring of R&D resources?including human resources and critical laboratory equipment?to optimize management of the company’s R&D project portfolio Establish a transparent project platform to enable better product and process planning, gain insight into product performance, and facilitate advanced analytics that support R&D and overall business decisions Identify potential roadblocks for better risk management Solutions Worked with Oracle Partner PRM to implement Oracle’s Primavera P6 Enterprise Project Portfolio Management to manage the entire household-appliance, R&D project portfolio lifecycle, enabling managers and project leaders to better track and monitor resources and deliverables in real time Improved risk analysis and evaluation abilities for R&D projects Supported long-term planning needs Used advanced reporting features to capture data needed for budgeting and other project details, including employee performance evaluations Improved monitoring abilities and insight into the overall performance of products postproduction Enabled flexible, fast, and customized reporting with the P6 dashboard on a centralized platform to meet custom reporting needs for project leaders and support on-time and on-budget deliverables Integrated with other corporate departments, such as accounts payable, to upload project invoice data into the Primavera solution and the company’s e-mail system, so that project leaders will be alerted about milestones and other project related information Partner“Oracle Partner PRM provided us with a quick, reliable, and solution-focused approach to its support,” said Iffet Iyigun Meydanli, innovation and system development manager, R&D Center, Arçelik A.S. “The company’s service covered the entire spectrum of our needs, including implementation, training, configuration, problem solving, and integration.”

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• Using VLANs/subnetting to separate management from services?

  - by YouAreTheHat

  Background: I recently purchased a server and a managed switch for my home in the hopes of getting more experience and some fun toys to play with. The devices and appliances I either have or plan to have cover a broad spectrum: router, DD-WRT AP, Dell switch, OpenLDAP server, FreeRADIUS server, OpenVPN gateway, home PCs, gaming consoles, etc. I intend to segment my network with VLANs and associated subnets (e.g., VID10 is populated by devices on 192.168.10.0/24). The idea is to secure the more sensitive appliances by forcing traffic through my router/FW. Setup: After thinking and planning for some time, I have tentatively decided on 4 VLANs: one for the WAN connection, one for servers, one for home/personal devices, and one for management. In theory, the home VLAN will have limited access to the servers, and the management VLAN will be totally isolated for security. Question: Since I want to restrict access to management interfaces, but some appliances have to be accessible to other devices, is it possible/wise to have only management (SSH, HTTP, RDP) available on one VLAN/IP and only services (LDAP, DHCP, RADIUS, VPN) available on other? Is this a thing that is done? Does it gain me the security I think it does, or hurt me in some way?

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• Computer speakers receive radio station signal

  - by squircle

  I have a set of Logitech 5.1 speakers where each speaker and the source plug into the subwoofer. I'm using a Griffin Firewave with output from my MacBook Pro, and output from my custom-built desktop with a switch in the middle (built it myself out of an old Belkin A/B parallel switch). Recently, I've noticed that I can hear a local Punjabi radio station being picked up by my speakers, and the volume of this interference increases as I increase the volume of the speakers. I'm fairly sure that this radio station is at the low-end of the FM spectrum, below 90MHz (or it may be at the high end, above 105MHz, my memory isn't infallible). It gets quite annoying as I can't put my audio very loud without the interference. I've tried to put a ferrite core on the input cable just before the 3.5mm jacks plug into the subwoofer. I don't know if putting the same core around all three of the cables (green, black, orange) would negate the effects, but I'm assuming not. There has been no change. Is there any reason why this would be happening? I'm assuming the interference is coming somewhere between the FireWave and the subwoofer, because the noise gets amplified with volume increases. If anybody has any suggestions, I'd be grateful!

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• Improving abysmal 802.11n wireless network

  - by concept

  I am in desperate need of help to improve the abysmal performance of my 802.11n wireless network. At best I get 30Mbs (this is an internet download) from a technology that boasts 300Mbs, even worse is the LAN where to date best i have ever gotten is 1Mbs. It is literally quicker to copy the file to a USB and walk it to the other computer. Infrastructure is this AP 802.11n only broadcasting at both 2.4GHz and 5GHz Mac with 802.11a/b/g/n card is connected to the AP via 5GHz Linux with 802.11a/b/g/n card is connected to AP via 2.4GHz I have conducted the following tests (results at end of post) Internet based speed test wired and wireless LAN file copy wired and wireless I have read: http://nutsaboutnets.com/troubleshooting-wi-fi-problems/ http://www.smallnetbuilder.com/wireless/wireless-basics/30664-5-ways-to-fix-slow-80211n-- speed http colon //www.wi-fiplanet dot com/tutorials/7-tips-to-increase-wi-fi-performance.html Slow file transfer on network between two 802.11n laptops (connected directly together via access point) Wireless Network Performance Issues Slower than expected 802.11n wireless network speeds I have made the following optimizations AP broadcasts only 802.11n on both 2.4GHz and 5GHz frequencies 2.4GHz is on a channel with least interference (live in an apartment with lots of APs), this did make a 10Mb/sec improvement Our AP is the only one transmitting on the 5GHz freq. Security: WPA Personal WPA2 AES encryption Bandwidth: 20MHz / 40MHz (i assume this to be channel bonding) I have tried the following with 0 improvement Dropped the Fragment Threshold to 512 Dropped the Request To Send (RTS) Threshold to 512 and 1 Even thought of buying a frequency spectrum analyzer, until i saw the cost of them!!! Speed test results Linux Wired: DOWNLOAD 128.40Mb/s UPLOAD 10.62Mb/s www dot speedtest dot net/my-result/2948381853 Mac Wired: DOWNLOAD 118.02Mb/s UPLOAD 10.56Mb/s www dot speedtest dot net/my-result/2948384406 Linux Wireless: DOWNLOAD 23.99Mb/s UPLOAD 10.31Mb/s www.speedtest dot net/my-result/2948394990 Mac Wireless: DOWNLOAD 22.55Mb/s UPLOAD 10.36Mb/s www.speedtest dot net/my-result/2948396489 LAN NFS 53,345,087 bytes (51Mb) file Linux Mac NFS Wired: 65.6959 Mb/sec Linux Mac NFS Wireless: .9443 Mb/sec All help is appreciated, even testing methods will be accepted.

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• Help with memory usage issues on VPS

  - by Niall Collins

  Hi there, I am running a VPS server with 6 .net web sites/applications running on it. I am having issues with performance on the server, mainly it running out of memory. I contacted the company that lease the server to me and they told me it was because I also had sql server 2008 express also running on the server. So I went ahead and removed this, uninstalled etc. However I still seem to be having issues. For example at present, looking at resource consumption, the virtual memory is: ID: vprvmem Current Use: 894,328,832 bytes Limit: 1,073,741,824 bytes This means useage of ~80%. Is there any way I can check out exactly that applications, web sites, software is taking up most of the servers memory, so I can look at rectifying it. I feel that 80% is much to high to allow for contingency for a spike in traffic. I have got extra memory resources added to the box recently, but I would prefer finding the source of the problem rather than throwing extra memory at it. Maybe these levels are correct and alls running ok, but would like to investigate it to make sure. My knowledge of hardware is limited as I mostly deal in the spectrum of software. So any tools out there that can help me or any pertient advice.

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• (manually configured) kernel update leaves wireless in a mess

  - by Mala

  I recently upgraded my kernel from 2.6.31-gentoo-r6 to 2.6.32-gentoo-r7. In both cases, I configured everything manually. However, since the upgrade, my wireless card appears to be on the fritz. It will connect to networks just fine, and remain connected, but can only access the internet (and other hosts on the network) for about 3 seconds after connecting. Reconnecting to the network appears to fix the problem... for another 3 seconds or so. The problem is "solved" by booting into the older kernel. The relevant lspci entry is 02:00.0 Network controller: Intel Corporation PRO/Wireless 5300 AGN [Shiloh] Network Connection I'm pretty sure I have the correct drivers enabled in the kernel Device Drivers ---> Network device support ---> Wireless LAN (IEEE 802.11) ---> <*> Intel Wireless Wifi [*] Enable LED support in iwlagn and iwl3945 drivers [*] Enable Spectrum Measurement in iwlagn driver [*] Enable full debugging output in iwlagn and iwl3945 drivers <*> Intel Wireless WiFi Next Gen AGN (iwlagn) [*] Intel Wireless WiFi 4965AGN [*] Intel Wireless WiFi 5000AGN; Intel WiFi Link 1000, 6000, and 6050 Series I tried with the other intel drivers enabled as well (iwl3945) and no difference. Is there something stupid I'm missing? Is there something I have to recompile after upgrading the kernel (a la nvidia)? Thanks Mala

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• Erratic WiFi 2.4 GHz channel spikes, what gives?

  - by Francis W. Usher

  Sorry guys, first a gripe about my neighbor's WiFi access point (it is related): they totally hog the center nine 2.4 GHz channels (3-11), centered right at 7! I know the outer regions of the signal don't make as much of a difference, and technically they're running channels 5 & 9. Anyway, their signal is clearly interfering with mine, which is necessarily centered at 3 or 11 to evade their interference. I guess it's somewhat a case of access point envy: they happen to have both a stronger signal and a higher data rate, while occupying twice the band width that I do. Getting to the point, I've noticed that they tend to sit nice and pretty centered at 7, but they definitely auto-select their channel, and I've noticed that the auto-selection algorithm tends to shift towards the higher channels; hence I decided to pick channel 3, and I don't get so many intermittent lag spikes any more. Anyway, the thing that weirded me out was the reason they have to auto-select sometimes: unexplained, powerful (talking order of 0dB here), giant spikes of 2.4 GHz activity in consistent regions of the spectrum. I don't think it's just noise, since my wireless monitoring software is registering a MAC address, a manufacturer, and usually a fairly coherent ascii name... and it seems to be a fairly well-confined signal. But these signals are fairly common, and they do some weird stuff to my signal. So my question is what are these signals? Where are they coming from? Where are they going? Why are they so ridiculously strong? Why don't they ever last very long? Here's an inSSIDer screenshot I took, for your perusal. I am labeled with "me", my greedy neighbor labeled with "neighbor", and the 2 quasar signals are labeled with "WTF?".

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• Why does my microwave kill the Wi-Fi?

  - by Ohlin

  Every time I start the microwave in the kitchen, our home Wi-Fi stops working and all devices lose connection with our router! The kitchen and the Wi-Fi router are in opposite ends of the apartment but devices are being used a little here and there. We've been annoyed by the instability of the Wi-Fi for some time and it wasn't until recently we realized it was correlated to microwave usage. After some testing with having the microwave on and off we could narrow down the problem to only occurring when the router is in b/g/n mode and uses a set channel. If I change to b/g mode or set channel to auto then there is no problem any more...but still! The router is a Zyxel P-661HNU ("802.11n Wireless ADSL2+ 4-port Security Gateway" with latest firmware) and the microwave is made by Neff with an effect of 1000W (if this information might be useful to anyone). There is an "internet connection" light on the router and it doesn't go out when the interruption occurs so I think this is only an internal Wi-Fi issue. Now to my questions: What parts of the Wi-Fi can possibly be affected by the microwave usage? Frequency? Disturbances in the electrical system? How can setting Auto on channels make a difference? I thought the different channels were just some kind of separation system within the same frequency spectrum? Could this be a sign that the microwave is malfunctioning and slowly roasting us all at home? Is there any need to be worried? Since we were able to find router settings that cooperate well with our microwave's demand for attention, this question is mainly out of curiosity. But as most people out there...I just can't help the fact that I need to know how it's possible :-)

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