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  • Using wifi router as bridge to increase signal?

    - by overtherainbow
    A friend of mine lives in an appartment building whose structure is such that wifi signal is very weak. Even a USB key won't work. I was thinking of buying an entry-level wifi router and reconfigure it as a bridge to act as repeater. Would that increase the chance of getting a good signal, or I shouldn't bother? If experience shows that it does improve things significantly, is their another router I should look at besides the Linux-based Linksys models? Thank you.

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  • SQLAuthority News – Download Whitepaper – Enabling and Securing Data Entry with Analysis Services Writeback

    - by pinaldave
    SQL Server Analysis Service have many features which are commonly requested and many already exists in the system. Security Data Entry is very important feature and SSAS supports writeback feature.  Analysis Services is a tool for aggregating information and providing business users with the ability to analyze and support decision making in their business. By using the built-in writeback feature in Analysis Services, business users can also modify their data points to perform what-if analysis or supplement any existing data. The techniques described in this article derive from the author’s professional experience in the design and development of complex financial analysis applications used by various business groups in a large multinational company. Download Whitepaper Enabling and Securing Data Entry with Analysis Services Writeback. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Documentation, SQL Download, SQL Query, SQL Server, SQL Tips and Tricks, SQL White Papers, T SQL, Technology

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  • Why some consider static analysis a testing and some do not?

    - by user970696
    Preparing myself also to ISTQB certification, I found they call static analysis actually as a static testing, while some engineering book distinct between static analysis and testing, which is the dynamic activity. I tent to think that static analysis is not a testing in the true sense as it does not test, it checks/verifies. But sure I would love to hear opinion of the true experts here. Thank you

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  • Architecture for Qt SIGNAL with subclass-specific, templated argument type

    - by Barry Wark
    I am developing a scientific data acquisition application using Qt. Since I'm not a deep expert in Qt, I'd like some architecture advise from the community on the following problem: The application supports several hardware acquisition interfaces but I would like to provide an common API on top of those interfaces. Each interface has a sample data type and a units for its data. So I'm representing a vector of samples from each device as a std::vector of Boost.Units quantities (i.e. std::vector<boost::units::quantity<unit,sample_type> >). I'd like to use a multi-cast style architecture, where each data source broadcasts newly received data to 1 or more interested parties. Qt's Signal/Slot mechanism is an obvious fit for this style. So, I'd like each data source to emit a signal like typedef std::vector<boost::units::quantity<unit,sample_type> > SampleVector signals: void samplesAcquired(SampleVector sampleVector); for the unit and sample_type appropriate for that device. Since tempalted QObject subclasses aren't supported by the meta-object compiler, there doesn't seem to be a way to have a (tempalted) base class for all data sources which defines the samplesAcquired Signal. In other words, the following won't work: template<T,U> //sample type and units class DataSource : public QObject { Q_OBJECT ... public: typedef std::vector<boost::units::quantity<U,T> > SampleVector signals: void samplesAcquired(SampleVector sampleVector); }; The best option I've been able to come up with is a two-layered approach: template<T,U> //sample type and units class IAcquiredSamples { public: typedef std::vector<boost::units::quantity<U,T> > SampleVector virtual shared_ptr<SampleVector> acquiredData(TimeStamp ts, unsigned long nsamples); }; class DataSource : public QObject { ... signals: void samplesAcquired(TimeStamp ts, unsigned long nsamples); }; The samplesAcquired signal now gives a timestamp and number of samples for the acquisition and clients must use the IAcquiredSamples API to retrieve those samples. Obviously data sources must subclass both DataSource and IAcquiredSamples. The disadvantage of this approach appears to be a loss of simplicity in the API... it would be much nicer if clients could get the acquired samples in the Slot connected. Being able to use Qt's queued connections would also make threading issues easier instead of having to manage them in the acquiredData method within each subclass. One other possibility, is to use a QVariant argument. This necessarily puts the onus on subclass to register their particular sample vector type with Q_REGISTER_METATYPE/qRegisterMetaType. Not really a big deal. Clients of the base class however, will have no way of knowing what type the QVariant value type is, unless a tag struct is also passed with the signal. I consider this solution at least as convoluted as the one above, as it forces clients of the abstract base class API to deal with some of the gnarlier aspects of type system. So, is there a way to achieve the templated signal parameter? Is there a better architecture than the one I've proposed?

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  • central apache log analysis of many hosts

    - by Jason Antman
    We have 30+ apache httpd servers, and are looking to perform analysis on the logs both for historical trending and near "real time" monitoring/alerting. I'm mainly interested in things like error rates (4xx/5xx), response time, overall request rate, etc. but it would also be very useful to pull out more compute-intensive statistics like unique client IPs and user agents per unit of time. I'm leaning towards building this as a centralized collector/server/storage, and am also considering the possibility of storing non-apache logs (i.e. general syslog, firewall logs, etc.) in the same system. Obviously a large part of this will probably have to be custom (at least the connection between pieces and the parsing/analysis we do), but I haven't been able to find much information on people who have done stuff like this, at least at shops smaller than Google/Facebook/etc. who can throw their log data into a hundred-node compute cluster and run Map/Reduce on it. The main things I'm looking for are: - All open source - Some way of collecting logs from apache machines that isn't too resource-intensive, and transports them relatively quickly over the network - Some way of storing them (NoSQL? key-value store?) on the backend, for a given amount of time (and then rolling them up into historical averages) - In the middle of this, a way of graphing in near-real-time (probably also with some statistical analysis on it) and hopefully alerting off of those graphs. Any suggestions/pointers/ideas, to either "products"/projects or descriptions of how other people do this would be greatly helpful. Unfortunately, we're not exactly a new-age-y devops shop, lots of old stuff, homogeneous infrastructure, and strained boxes.

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  • Matlab: Analysis of signal

    - by Mateusz
    Hi, I have a problem with this task: For free route perform frequency analysis and give parametrs of each signal component: time of beginning and ending of each component beginning and ending frequency amplitude (in time domain) in the beginning and end of each signal's component level of noise in dB Assume, that, the parametrs of each component like amplitude, frequency is changing lineary in time. Frequency of sampling is 1000Hz For example I have signal like this: Nx=64; fs=1000; t=1/fs*(0:Nx-1); %========================== A1=1; A2=4; f1=500; f2=1000; x1=A1*cos(2*pi*f1*t); x2=A2*sin(2*pi*f2*t); %========================== x=x1+x2;

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  • EPM Architecture: Reporting and Analysis

    - by Marc Schumacher
    Reporting and Analysis is the basis for all Oracle EPM reporting components. Through the Java based Reporting and Analysis web application deployed on WebLogic, it enables users to browse through reports for all kind of Oracle EPM reporting components. Typical users access the web application by browser through Oracle HTTP Server (OHS). Reporting and Analysis Web application talks to the Reporting and Analysis Agent using CORBA protocol on various ports. All communication to the repository databases (EPM System Registry and Reporting and Analysis database) from web and application layer is done using JDBC. As an additional data store, the Reporting and Analysis Agent uses the file system to lay down individual reports. While the reporting artifacts are stored on the file system, the folder structure and report based security information is stored in the relational database. The file system can be either local or remote (e.g. network share, network file system). If an external user directory is used, Reporting and Analysis services also communicate to this directory. The next post will cover WebAnalysis.

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  • Write a signal handler to catch SIGSEGV

    - by Adi
    Hi all, I want to write a signal handler to catch SIGSEGV. First , I would protect a block of memory for read or writes using char *buffer; char *p; char a; int pagesize = 4096; " mprotect(buffer,pagesize,PROT_NONE) " What this will do is , it will protect the memory starting from buffer till pagesize for any reads or writes. Second , I will try to read the memory by doing something like p = buffer; a = *p This will generate a SIGSEGV and i have initialized a handler for this. The handler will be called . So far so good. Now the problem I am facing is , once the handler is called, I want to change the access write of the memory by doing mprotect(buffer, pagesize,PROT_READ); and continue my normal functioning of the code. I do not want to exit the function. On future writes to the same memory, I want again catch the signal and modify the write rights and then take account of that event. Here is the code I am trying : #include <signal.h> #include <stdio.h> #include <malloc.h> #include <stdlib.h> #include <errno.h> #include <sys/mman.h> #define handle_error(msg) \ do { perror(msg); exit(EXIT_FAILURE); } while (0) char *buffer; int flag=0; static void handler(int sig, siginfo_t *si, void *unused) { printf("Got SIGSEGV at address: 0x%lx\n",(long) si->si_addr); printf("Implements the handler only\n"); flag=1; //exit(EXIT_FAILURE); } int main(int argc, char *argv[]) { char *p; char a; int pagesize; struct sigaction sa; sa.sa_flags = SA_SIGINFO; sigemptyset(&sa.sa_mask); sa.sa_sigaction = handler; if (sigaction(SIGSEGV, &sa, NULL) == -1) handle_error("sigaction"); pagesize=4096; /* Allocate a buffer aligned on a page boundary; initial protection is PROT_READ | PROT_WRITE */ buffer = memalign(pagesize, 4 * pagesize); if (buffer == NULL) handle_error("memalign"); printf("Start of region: 0x%lx\n", (long) buffer); printf("Start of region: 0x%lx\n", (long) buffer+pagesize); printf("Start of region: 0x%lx\n", (long) buffer+2*pagesize); printf("Start of region: 0x%lx\n", (long) buffer+3*pagesize); //if (mprotect(buffer + pagesize * 0, pagesize,PROT_NONE) == -1) if (mprotect(buffer + pagesize * 0, pagesize,PROT_NONE) == -1) handle_error("mprotect"); //for (p = buffer ; ; ) if(flag==0) { p = buffer+pagesize/2; printf("It comes here before reading memory\n"); a = *p; //trying to read the memory printf("It comes here after reading memory\n"); } else { if (mprotect(buffer + pagesize * 0, pagesize,PROT_READ) == -1) handle_error("mprotect"); a = *p; printf("Now i can read the memory\n"); } /* for (p = buffer;p<=buffer+4*pagesize ;p++ ) { //a = *(p); *(p) = 'a'; printf("Writing at address %p\n",p); }*/ printf("Loop completed\n"); /* Should never happen */ exit(EXIT_SUCCESS); } The problem I am facing with this is ,only the signal handler is running and I am not able to return to the main function after catching the signal.. Any help in this will be greatly appreciated. Thanks in advance Aditya

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  • R and SPSS difference

    - by sfactor
    i will be analysing vast amount of network traffic related data shortly. i will pre-process the data in order to analyse it. i have found that R and SPSS are among the most popular tools for statistical analysis. i will also be generating quite a lot of graphs and charts. so i was wondering what is the basic difference between these two softwares. i am not asking which one is better. i just wanted to know what are the difference in terms of workflow between the two besides the fact that SPSS has a GUI. I will be mostly working with scripts in either case anyway so i wanted to know about the other differences.

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  • layout analysis of text based pdf without ocr

    - by fastrack
    Before recognizing a pdf, OCR software do document layout analysis to determine which parts are texts, tables or images, as shown in the picture below. ![papercrop]http://cache.gawkerassets.com/assets/images/17/2011/07/papercrop.jpg I want to use some parts of the text while leaving out the others. So having a software marking those zones comes in handy. Papercrop does a decent job, but it has a bug of now showing some of the text in the pdf file. And OCR software can also do layout analysis, marking out "zones" which I can add or delete. But you have to OCR to do that. Since my pdfs are already text based, I don't want to waste so much time OCRing. So my question is, is there any software that automatically mark out those zones and let me manually manipulate them, without having to OCR? Thanks! Waiting for your help.

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  • Get Cell RSSI(Network Signal Strength) on Android 1.5

    - by Brandon
    Is there any way to retrieve the current cellular Signal Strength (RSSI) on Android 1.5? I know there's a way to listen for signal strength updates through the TelephonyManager, but this seems to only give a "state," not a numeric value. Is using the RSSI field on a neighboring cell fairly accurate? I'm guessing not, but I'm running out of ideas.

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  • Input signal out of range; Change settings to 1600 x 900

    - by Clayton
    I recently installed Ubuntu 12.04 onto my HP Pavilion, in an attempt to make the desktop able to dual-boot Windows 7 and Ubuntu. I managed to get down to the last step, and finished the installation process. After it prompted me to remove what I used to install Ubuntu, I did so, removing my SanDisk 8GB flash drive, and allowed the system to reboot. Like usual, the desktop booted with the HP image, with the options at the bottom(Boot Menu, System Recovery, etc). However, when it should have started up with Ubuntu(like I'm certain it should have done), I received the following error: Input signal out of range Change settings to 1600 x 900 From the time I installed the operating system, back in late August, till now, I've been trying to figure out how I would go about fixing this issue. My mom is also starting to get frustrated with my not having resolved the issue, as its the only desktop that has a printer installed. Is there any possible way to resolve this? To summarize the problem: -Successful boot -Screen brings up error -Screen goes to standby -Nothing else possible until desktop is rebooted, which will initiate the above three steps A few notes: -I did not back up my computer before I installed Ubuntu. I didn't have anything to write to, and basically just forgot to. : -I don't have a Recovery Disk. -I don't have the Windows 7 disk that is supposed to come with the computer. -It has been narrowed down by a friend on Skype that the problem lies with the display, and that the vga= boot command does have something to do with fixing the problem Thank you in advance for resolving this problem. I greatly appreciate it. ^^

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  • Signal amplitude against time in Java

    - by wsr74ws84
    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 very little about Java, I hope someone can help me.

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  • why this signal handler is called infinitely

    - by lz_prgmr
    I am using Mac OS 10.6.5, g++ 4.2.1. And meet problem with following code: #include <iostream> #include <sys/signal.h> using namespace std; void segfault_handler(int signum) { cout << "segfault caught!!!\n"; } int main() { signal(SIGSEGV, segfault_handler); int* p = 0; *p = 100; return 1; } It seems the segfault_handler is called infinitely and keep on print: segfault caught!!! segfault caught!!! segfault caught!!! ... I am new to Mac development, do you have any idea on what happened?

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  • GTK+ (2.0) - signal "clicked" on GtkEntry?

    - by Lght
    i'm testing some signals with Gtk+ 2.0. Actually, i'm looking for a way to get the signal emitted when i click on a GtkEntry. if (widgets_info[i].action & IG_INPUT) { widget->frame[i] = gtk_entry_new_with_max_length(MAX_INPUT_LENGTH); gtk_entry_set_text(widget->frame[i], widgets_info[i].text); catch_signal(widget->frame[i], MY_SIGNAL, &change_entry, widget); } I have a pre-selected text in my entry (widgets_info[i].text) and i want this text to disappear if the user click on my GtkEntry. Does someone knows what is this signal ? Sincerely, Lght (sorry for my english)

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  • Building a home cluster - hardware and cost analysis

    - by ldigas
    Does anyone know some links / books / anything you can think of, that describe the process of building a little home cluster (when I say home, it doesn't necessarily mean for keeping at home - just means it's relatively cheap and small) for experimental purposes, with a special emphasis on what hardware would be adequate today, and some kind of cost analysis ? Although, if someone here's done it, I'd appreciate all the experience you can share.

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  • Excel Free Text Survey Question Analysis

    - by joec
    I have to analyse a survey. The survey consists of some yes/no questions, some numeric questions and some questions like the following (free text where respondents have entered multiple answers). Do you have any social networking accounts (Facebook, Twitter, Myspace etc) Y N If yes, which ones _____________________________ Respondents answer: Facebook and Twitter How do I put these types of answer into Excel to gain some sort of useful analysis? Thanks. PS. I know Excel is not great for surveys, but can't spend $1000 on SPSS or similar.

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  • Static analysis tool customization for any language

    - by Sam
    Hi, We are using a Tool in our project. This tool has its own language which is similar to Java. I am looking for a static analysis tool which can be applied to the new language. Are there any static analysis tools which can be customized to any languages? or Is there any document or any reference on how to develop the static analysis tool for our own languages? Thanks.

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  • Static analysis framework for eclipse?

    - by autobiographer
    i just wanted to use eclipse tptp, a framework for static code analysis but the support for code analysis ended with tptp 4.5.0. 1. it seems that this version can not be integrated into the current eclipse galileo. am i right? 2. which language independant framework for eclipse would you use as an alternative for tptp static analysis which works with eclipse galileo?

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