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  • The Alienware M11xR3 has arrived

    - by Enrique Lima
    A week or so ago, I mentioned my gear was evolving.  The newest member of my gear arrived yesterday, an Alienware M11xR3. Here are the specs: Intel Core i7-2617M 1.5GHz (2.6GHz Turbo Mode, 4MB Cache) NVIDIA GeForce GT540 graphics with 2.0GB Video Memory and Optimus 16GB Dual Channel DDR3 at 1333MHz 11.6in High Def (720p/1366x768) with WLED backlight 750GB 7200RPM SATA 3Gb/s Soundblaster X-Fi Hi Def Audio - Software Enabled Intel Advanced-N WiFi Link 6250 a/g/n 2x2 MIMO Technology with WiMax Gobi Mobile Broadband with GPS - supports ATT with contract Internal Bluetooth 3.0   Some pics from the unboxing event:

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  • Why is my CPU being used while doing nothing?

    - by Jop
    I have installed Ubuntu GNOME in BIOS mode on my MacBook (BIOS mode so that the proprietary NVIDIA drivers work. I need them for gaming.). For some reason, a lot of CPU is being used while not really doing anything. It swings between 20-30% on both cores, usually. But when I look at the list of processes and sort by CPU usage, I do not see anything special. No processes intensively doing anything. How can I fix this? EDIT: Output of top command. jop@jop-MacBook:~$ top top - 17:08:02 up 41 min, 2 users, load average: 0,51, 0,69, 0,95 Tasks: 202 total, 2 running, 200 sleeping, 0 stopped, 0 zombie %Cpu(s): 11,9 us, 5,8 sy, 0,0 ni, 80,3 id, 0,5 wa, 0,0 hi, 1,5 si, 0,0 st KiB Mem: 7908316 total, 2919940 used, 4988376 free, 153248 buffers KiB Swap: 3906244 total, 0 used, 3906244 free, 1326544 cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 3785 root 20 0 195m 82m 26m S 22,9 1,1 2:43.77 Xorg 4429 jop 20 0 1543m 150m 60m S 7,3 1,9 1:26.26 compiz 4198 jop 20 0 633m 21m 11m S 1,7 0,3 0:04.96 unity-panel-ser 7425 jop 20 0 564m 18m 12m S 1,7 0,2 0:00.84 gnome-terminal 7019 jop 20 0 806m 89m 46m S 1,0 1,2 0:10.01 chrome 7323 jop 20 0 966m 93m 23m S 1,0 1,2 0:06.85 chrome 6742 root 20 0 0 0 0 S 0,7 0,0 0:00.43 kworker/0:3 3 root 20 0 0 0 0 S 0,3 0,0 0:06.01 ksoftirqd/0 7008 root 20 0 0 0 0 S 0,3 0,0 0:00.27 kworker/1:3 7302 jop 20 0 972m 96m 28m S 0,3 1,2 0:06.32 chrome 7310 jop 20 0 382m 63m 39m S 0,3 0,8 0:00.34 chrome 7498 jop 20 0 24840 1600 1120 R 0,3 0,0 0:00.22 top 1 root 20 0 27176 2944 1412 S 0,0 0,0 0:01.58 init 2 root 20 0 0 0 0 S 0,0 0,0 0:00.00 kthreadd 5 root 0 -20 0 0 0 S 0,0 0,0 0:00.00 kworker/0:0H 6 root 20 0 0 0 0 S 0,0 0,0 0:00.00 kworker/u4:0 7 root rt 0 0 0 0 S 0,0 0,0 0:02.04 migration/0 Even when xorg isn't so busy like when I copied, CPU usage is higher then what the processes use.

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  • blender: 3D model from guide images

    - by Stefan
    In a effort to learn the blender interface, which is confusing to say the least, I've chosen to model a model from referrence pictures easily found on the web. Problem is that I can't ( and won't ) get perfect "right", "front" and "top" pictures. Blender only allows you to see the background pictures when in ortographic mode and only from right|front|top, which doesn't help me. How to I proceed to model from non-perfect guide images?

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  • How to Restore Your Files From the Windows.old Folder After Upgrading

    - by Taylor Gibb
    If you have ever upgraded your Windows installation without formatting, you have probably come across the Windows.old folder which houses all the files from your previous installation. Here’s how to use it to restore your files. How to Factory Reset Your Android Phone or Tablet When It Won’t Boot Our Geek Trivia App for Windows 8 is Now Available Everywhere How To Boot Your Android Phone or Tablet Into Safe Mode

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  • Bash command history not working

    - by creepylol
    The command history between sessions is not getting saved. I'm using guake and the history for the session is working fine. I noticed that .bash_history had some commands I executed in "sudo -s" mode and tried the same again and all the commands while in the session got saved so I tried "chmod 777 .bash_history" Now the old commands appear at the start of a session but no new commands are getting saved Thanx in advance

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  • Wireless networks are not detected at start up in Ubuntu 12.04

    - by Kanhaiya Mishra
    I have recently (three four days ago) installed Ubuntu 12.04 via windows installer i.e. wubi.exe. After the installation completed wireless and Ethernet were both working well. But after restart wireless networks didn't show up while in the network manager both networking and wireless were enabled. Though sometimes after boot it did show the networks available but very rarely. So I went through various posts regarding wireless issues in Ubuntu 12.04 and tried so many things but ended up in nothing satisfactory. I have Broadcom 4313 LAN network controller and brcmsmac driver. Then relying on some suggestions I tried to install bcm-wl driver but couldn't install due to some error in jockeyl.log file. Then i tried fresh installation of the same driver but still could resolve the startup issues with wireless. Then again I reinstalled Ubuntu inside windows using wubi installer. This time again same problem occurred after boot. But this time I successfully installed wl driver before disturbing file-system files of Ubuntu. But again the same issue. This time I noticed some new things: If I inserted Ethernet/LAN cable before startup then wireless networks are available and of course LAN(wired) networks also work. but if i don't plug in cable before startup and then plug it after startup then it didn't detect Ethernet network neither wireless. So I haven't noticed it before that LAN along with wifi also doesn't work after startup. But if i suspend the session and make it sleep and again login then it worked. I tried it every time that WLAN worked perfectly. But still i m unable to resolve that startup problem. Each time i boot first I have to suspend it once then only networks are available. It irritates me each time i reboot/boot my lappy. So please help out of this problem. Any ideas/help regarding this issue would be highly appreciated. Some of the commands that i run gave following results: # lspci 00:00.0 Host bridge: Intel Corporation Core Processor DRAM Controller (rev 12) 00:02.0 VGA compatible controller: Intel Corporation Core Processor Integrated Graphics Controller (rev 12) 00:16.0 Communication controller: Intel Corporation 5 Series/3400 Series Chipset HECI Controller (rev 06) 00:1a.0 USB controller: Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller (rev 06) 00:1b.0 Audio device: Intel Corporation 5 Series/3400 Series Chipset High Definition Audio (rev 06) 00:1c.0 PCI bridge: Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 1 (rev 06) 00:1c.1 PCI bridge: Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 2 (rev 06) 00:1c.5 PCI bridge: Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 6 (rev 06) 00:1d.0 USB controller: Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller (rev 06) 00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev a6) 00:1f.0 ISA bridge: Intel Corporation Mobile 5 Series Chipset LPC Interface Controller (rev 06) 00:1f.2 SATA controller: Intel Corporation 5 Series/3400 Series Chipset 6 port SATA AHCI Controller (rev 06) 00:1f.3 SMBus: Intel Corporation 5 Series/3400 Series Chipset SMBus Controller (rev 06) 00:1f.6 Signal processing controller: Intel Corporation 5 Series/3400 Series Chipset Thermal Subsystem (rev 06) 03:00.0 Network controller: Broadcom Corporation BCM4313 802.11b/g/n Wireless LAN Controller (rev 01) 04:00.0 Ethernet controller: Atheros Communications Inc. AR8152 v1.1 Fast Ethernet (rev c1) ff:00.0 Host bridge: Intel Corporation Core Processor QuickPath Architecture Generic Non-core Registers (rev 02) ff:00.1 Host bridge: Intel Corporation Core Processor QuickPath Architecture System Address Decoder (rev 02) ff:02.0 Host bridge: Intel Corporation Core Processor QPI Link 0 (rev 02) ff:02.1 Host bridge: Intel Corporation Core Processor QPI Physical 0 (rev 02) ff:02.2 Host bridge: Intel Corporation Core Processor Reserved (rev 02) ff:02.3 Host bridge: Intel Corporation Core Processor Reserved (rev 02) # sudo lshw -C network *-network description: Wireless interface product: BCM4313 802.11b/g/n Wireless LAN Controller vendor: Broadcom Corporation physical id: 0 bus info: pci@0000:03:00.0 logical name: eth1 version: 01 serial: 70:f1:a1:49:b6:ab width: 64 bits clock: 33MHz capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless configuration: broadcast=yes driver=wl0 driverversion=5.100.82.38 ip=192.168.1.7 latency=0 multicast=yes wireless=IEEE 802.11 resources: irq:17 memory:f0500000-f0503fff *-network description: Ethernet interface product: AR8152 v1.1 Fast Ethernet vendor: Atheros Communications Inc. physical id: 0 bus info: pci@0000:04:00.0 logical name: eth0 version: c1 serial: b8:ac:6f:6b:f7:4a capacity: 100Mbit/s width: 64 bits clock: 33MHz capabilities: pm msi pciexpress vpd bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=atl1c driverversion=1.0.1.0-NAPI firmware=N/A latency=0 link=no multicast=yes port=twisted pair resources: irq:44 memory:f0400000-f043ffff ioport:2000(size=128) # lsmod | grep wl wl 2568210 0 lib80211 14381 2 lib80211_crypt_tkip,wl # sudo iwlist eth1 scanning eth1 Scan completed : Cell 01 - Address: 30:46:9A:85:DA:9A ESSID:"BH DASHIR 2" Mode:Managed Frequency:2.462 GHz (Channel 11) Quality:4/5 Signal level:-60 dBm Noise level:-98 dBm IE: IEEE 802.11i/WPA2 Version 1 Group Cipher : CCMP Pairwise Ciphers (1) : CCMP Authentication Suites (1) : PSK IE: Unknown: DD7F0050F204104A00011010440001021041000100103B000103104700109AFE7D908F8E2D381860668BA2E8D8771021000D4E4554474541522C20496E632E10230009574752363134763130102400095747523631347631301042000538333235381054000800060050F204000110110009574752363134763130100800020084 Encryption key:on Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 18 Mb/s 24 Mb/s; 36 Mb/s; 54 Mb/s; 6 Mb/s; 9 Mb/s 12 Mb/s; 48 Mb/s Cell 02 - Address: C0:3F:0E:EB:45:14 ESSID:"BH DASHIR 3" Mode:Managed Frequency:2.462 GHz (Channel 11) Quality:2/5 Signal level:-71 dBm Noise level:-98 dBm IE: IEEE 802.11i/WPA2 Version 1 Group Cipher : CCMP Pairwise Ciphers (1) : CCMP Authentication Suites (1) : PSK IE: Unknown: DD7F0050F204104A00011010440001021041000100103B00010310470010F3C9BBE499D140540F530E7EBEDE2F671021000D4E4554474541522C20496E632E10230009574752363134763130102400095747523631347631301042000538333235381054000800060050F204000110110009574752363134763130100800020084 Encryption key:on Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 18 Mb/s 24 Mb/s; 36 Mb/s; 54 Mb/s; 6 Mb/s; 9 Mb/s 12 Mb/s; 48 Mb/s Cell 03 - Address: A0:21:B7:A8:2F:C0 ESSID:"BH DASHIR 4" Mode:Managed Frequency:2.422 GHz (Channel 3) Quality:1/5 Signal level:-86 dBm Noise level:-98 dBm IE: IEEE 802.11i/WPA2 Version 1 Group Cipher : CCMP Pairwise Ciphers (1) : CCMP Authentication Suites (1) : PSK IE: Unknown: DD8B0050F204104A0001101044000102103B0001031047001000000000000010000000A021B7A82FC01021000D4E6574676561722C20496E632E10230009574E523130303076321024000456324831104200046E6F6E651054000800060050F20400011011001B574E5231303030763228576972656C6573732041502D322E344729100800020086103C000103 Encryption key:on Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s 9 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s; 36 Mb/s 48 Mb/s; 54 Mb/s

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  • Resources for Virtual Machine programming

    - by good_computer
    I am a beginner (a little more than that) programmer of C. I am really interested in the field of Virtual Machines. When I read about the Python VM, the PyPy project, the advancements in JVM technology, Google V8, the Erlang VM, I really get excited about these amazing pieces of technology, and really want to get my hands dirty building them or contributing to one of these projects. I need to know.. what are the things (language, concepts, algorithms, math, etc?) I need to know/learn to be able to build a virtual machine any books or other resources that will be helpful career prospects for a virtual machine engineer (but this is least important for me for now) (one more side question: somewhere I'd read something like JVM is on the cutting edge of virtual machine technology -- that it is the most advanced VM so far -- is that true?) Please give me a LONG answer detailing all that you know.

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  • Drawing a random x,y grid of objects within a prespective

    - by T Reddy
    I'm wrapping my head around OpenGL ES 2.0 and I think I'm trying to do something very simple, but I think the math may be eluding me. I created a simple, flat-ish cylinder in Blender that is 2 units in diameter. I want to create an arbitrary grid of these edge to edge (think of a checker board). I'm using a 3D perspective with GLKit: CGSize size = [[self view] bounds].size; _projectionMatrix = GLKMatrix4MakePerspective(GLKMathDegreesToRadians(45.0f), size.width/size.height, 0.1f, 100.0f); So, I managed to manually get all of these cylinders drawn on the screen just fine. However, I would like to understand how I can programmatically "fit" all of these cylinders on the screen at the same time given the camera location, screen size, cylinder diameter, and the number of rows/columns. So the net effect is that for small grids (i.e., 5x5) the objects are closer to the camera, but for large grids (i.e., 30x30) the objects are farther away. In either case, all of the cylinders are visible.

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  • Can't start ubuntu on Vaio Z

    - by teocomi
    Hello, I'm trying to install Ubuntu 10.10 32bit on this pc. I have both tried with Wubi from Windows and from USB stick, but after the installation process when I select to boot Ubuntu the screen becomes black and nothing happens (btw I can hear the cpu running)! Notice that maybe it is something related to the graphic card of the pc, since when I use Ubuntu in live mode or during the installation process all the graphics and colors are messed up as if there wasn't an appropriate diriver... What can I do?? Thanks

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  • the unity aspect ratio script looks good in computer but not in android phones

    - by Pooya Fayyaz
    I'm developing a game for android devices.and i have a script that solve the ratio problem but i have a problem in this code.and i dont know why.it looks perfect in computer even resize the game screen but in mobile phones have a problem.my game runs in landscape mode.this is the script : using UnityEngine; using System.Collections; using System.Collections.Generic; public class reso : MonoBehaviour { void Update() { // set the desired aspect ratio (the values in this example are // hard-coded for 16:9, but you could make them into public // variables instead so you can set them at design time) float targetaspect = 16.0f / 9.0f; // determine the game window's current aspect ratio float windowaspect = (float)Screen.width / (float)Screen.height; // current viewport height should be scaled by this amount float scaleheight = windowaspect / targetaspect; // obtain camera component so we can modify its viewport Camera camera = GetComponent<Camera>(); // if scaled height is less than current height, add letterbox if (scaleheight < 1.0f && Screen.width <= 490 ) { Rect rect = camera.rect; rect.width = 1.0f; rect.height = scaleheight; rect.x = 0; rect.y = (1.0f - scaleheight) / 2.0f; camera.rect = rect; } else // add pillarbox { float scalewidth = 1.0f / scaleheight; Rect rect = camera.rect; rect.width = scalewidth; rect.height = 1.0f; rect.x = (1.0f - scalewidth) / 2.0f; rect.y = 0; camera.rect = rect; } } } i figure that my problem occur in this part of the script: if (scaleheight < 1.0f) { Rect rect = camera.rect; rect.width = 1.0f; rect.height = scaleheight; rect.x = 0; rect.y = (1.0f - scaleheight) / 2.0f; camera.rect = rect; } and its look like this in my mobile phone in portrait: and in landscape mode:

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  • Applications: The Mathematics of Movement, Part 3

    - by TechTwaddle
    Previously: Part 1, Part 2 As promised in the previous post, this post will cover two variations of the marble move program. The first one, Infinite Move, keeps the marble moving towards the click point, rebounding it off the screen edges and changing its direction when the user clicks again. The second version, Finite Move, is the same as first except that the marble does not move forever. It moves towards the click point, rebounds off the screen edges and slowly comes to rest. The amount of time that it moves depends on the distance between the click point and marble. Infinite Move This case is simple (actually both cases are simple). In this case all we need is the direction information which is exactly what the unit vector stores. So when the user clicks, you calculate the unit vector towards the click point and then keep updating the marbles position like crazy. And, of course, there is no stop condition. There’s a little more additional code in the bounds checking conditions. Whenever the marble goes off the screen boundaries, we need to reverse its direction.  Here is the code for mouse up event and UpdatePosition() method, //stores the unit vector double unitX = 0, unitY = 0; double speed = 6; //speed times the unit vector double incrX = 0, incrY = 0; private void Form1_MouseUp(object sender, MouseEventArgs e) {     double x = e.X - marble1.x;     double y = e.Y - marble1.y;     //calculate distance between click point and current marble position     double lenSqrd = x * x + y * y;     double len = Math.Sqrt(lenSqrd);     //unit vector along the same direction (from marble towards click point)     unitX = x / len;     unitY = y / len;     timer1.Enabled = true; } private void UpdatePosition() {     //amount by which to increment marble position     incrX = speed * unitX;     incrY = speed * unitY;     marble1.x += incrX;     marble1.y += incrY;     //check for bounds     if ((int)marble1.x < MinX + marbleWidth / 2)     {         marble1.x = MinX + marbleWidth / 2;         unitX *= -1;     }     else if ((int)marble1.x > (MaxX - marbleWidth / 2))     {         marble1.x = MaxX - marbleWidth / 2;         unitX *= -1;     }     if ((int)marble1.y < MinY + marbleHeight / 2)     {         marble1.y = MinY + marbleHeight / 2;         unitY *= -1;     }     else if ((int)marble1.y > (MaxY - marbleHeight / 2))     {         marble1.y = MaxY - marbleHeight / 2;         unitY *= -1;     } } So whenever the user clicks we calculate the unit vector along that direction and also the amount by which the marble position needs to be incremented. The speed in this case is fixed at 6. You can experiment with different values. And under bounds checking, whenever the marble position goes out of bounds along the x or y direction we reverse the direction of the unit vector along that direction. Here’s a video of it running;   Finite Move The code for finite move is almost exactly same as that of Infinite Move, except for the difference that the speed is not fixed and there is an end condition, so the marble comes to rest after a while. Code follows, //unit vector along the direction of click point double unitX = 0, unitY = 0; //speed of the marble double speed = 0; private void Form1_MouseUp(object sender, MouseEventArgs e) {     double x = 0, y = 0;     double lengthSqrd = 0, length = 0;     x = e.X - marble1.x;     y = e.Y - marble1.y;     lengthSqrd = x * x + y * y;     //length in pixels (between click point and current marble pos)     length = Math.Sqrt(lengthSqrd);     //unit vector along the same direction as vector(x, y)     unitX = x / length;     unitY = y / length;     speed = length / 12;     timer1.Enabled = true; } private void UpdatePosition() {     marble1.x += speed * unitX;     marble1.y += speed * unitY;     //check for bounds     if ((int)marble1.x < MinX + marbleWidth / 2)     {         marble1.x = MinX + marbleWidth / 2;         unitX *= -1;     }     else if ((int)marble1.x > (MaxX - marbleWidth / 2))     {         marble1.x = MaxX - marbleWidth / 2;         unitX *= -1;     }     if ((int)marble1.y < MinY + marbleHeight / 2)     {         marble1.y = MinY + marbleHeight / 2;         unitY *= -1;     }     else if ((int)marble1.y > (MaxY - marbleHeight / 2))     {         marble1.y = MaxY - marbleHeight / 2;         unitY *= -1;     }     //reduce speed by 3% in every loop     speed = speed * 0.97f;     if ((int)speed <= 0)     {         timer1.Enabled = false;     } } So the only difference is that the speed is calculated as a function of length when the mouse up event occurs. Again, this can be experimented with. Bounds checking is same as before. In the update and draw cycle, we reduce the speed by 3% in every cycle. Since speed is calculated as a function of length, speed = length/12, the amount of time it takes speed to reach zero is directly proportional to length. Note that the speed is in ‘pixels per 40ms’ because the timeout value of the timer is 40ms.  The readability can be improved by representing speed in ‘pixels per second’. This would require you to add some more calculations to the code, which I leave out as an exercise. Here’s a video of this second version,

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  • SQL SERVER FIX : ERROR : 4214 BACKUP LOG cannot be performed because there is no current database b

    I recently got following email from one of the reader.Hi Pinal,Even thought my database is in full recovery mode when I try to take log backup I am getting following error.BACKUP LOG cannot be performed because there is no current database backup. (Microsoft.SqlServer.Smo)How to fix it?Thanks,[name and email removed as requested]Solution / Fix:This error can [...]...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • SkyDrive : Microsoft fait une auto-évaluation de son service de stockage Cloud et souhaite renforcer celui-ci

    Skydrive : Microsoft fait une évaluation de son service de stockage Cloud et souhaite renforcer celui-ci SkyDrive, la solution de stockage des données en mode Cloud de Microsoft, bien qu'ayant subir plusieurs mises à jour et adopter le HTML5 pour son interface utilisateur, afin d'améliorer l'expérience d'accès et de partage des documents, présente encore des limites. Omar Shahine et Mike Torres, tous deux gestionnaires de programme pour Skydrive analysent dans un billet de blog l'univers des services Cloud en général, et Skydrive en particulier avec ses manquements et les futures améliorations qui seront apportées au service. Microsoft distingue tout d'abord trois types de...

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  • what is itunes result sorted by ?

    - by NemesisII
    This is my App on Itunes: http://itunes.apple.com/us/app/buddy-calculator/id445261163?mt=8 My app Key word is : "calculator scientific calc equation math mathematics unit converter conversion statistic algebra" But when I search "Calculator" on Itunes, my app is not appeared (in first two pages). So I want to ask a question that how to improve the rank of my app , and what is the searched result sorted by (new first, vote or downloaded or ...) ? If I want to improve the rank, how can I do, does it cost fee or something ? Thanks you very much ^^ !

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  • Why does my program stutter so much?

    - by user36322
    I've been very frustrated trying to solve this. I've looked it up, and all the answers are the same: set IsFixedTimeStep = false. This doesn't help me at all, the program is still jittery and stutters. I have absolutely no idea what is going on, can you guys help? Code for movement (objects is a list): speed = Math.Min(speed + (speedIncrement * gameTime.ElapsedGameTime.Milliseconds / 200), maxSpeed); for (int i = objects.Count - 1; i >= 0; i--) { objects[i].rect.Y += (int)(speed * gameTime.ElapsedGameTime.Milliseconds); //Check if the object is past the screen. If it is, remove it if (objects[i].rect.Y > screenHeight) { objects.Remove(objects[i]); } }

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  • How to Implement Single Sign-On between Websites

    - by hmloo
    Introduction Single sign-on (SSO) is a way to control access to multiple related but independent systems, a user only needs to log in once and gains access to all other systems. a lot of commercial systems that provide Single sign-on solution and you can also choose some open source solutions like Opensso, CAS etc. both of them use centralized authentication and provide more robust authentication mechanism, but if each system has its own authentication mechanism, how do we provide a seamless transition between them. Here I will show you the case. How it Works The method we’ll use is based on a secret key shared between the sites. Origin site has a method to build up a hashed authentication token with some other parameters and redirect the user to the target site. variables Status Description ssoEncode required hash(ssoSharedSecret + , + ssoTime + , + ssoUserName) ssoTime required timestamp with format YYYYMMDDHHMMSS used to prevent playback attacks ssoUserName required unique username; required when a user is logged in Note : The variables will be sent via POST for security reasons Building a Single Sign-On Solution Origin Site has function to 1. Create the URL for your Request. 2. Generate required authentication parameters 3. Redirect to target site. using System; using System.Web.Security; using System.Text; public partial class _Default : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { string postbackUrl = "http://www.targetsite.com/sso.aspx"; string ssoTime = DateTime.Now.ToString("yyyyMMddHHmmss"); string ssoUserName = User.Identity.Name; string ssoSharedSecret = "58ag;ai76"; // get this from config or similar string ssoHash = FormsAuthentication.HashPasswordForStoringInConfigFile(string.Format("{0},{1},{2}", ssoSharedSecret, ssoTime, ssoUserName), "md5"); string value = string.Format("{0}:{1},{2}", ssoHash,ssoTime, ssoUserName); Response.Clear(); StringBuilder sb = new StringBuilder(); sb.Append("<html>"); sb.AppendFormat(@"<body onload='document.forms[""form""].submit()'>"); sb.AppendFormat("<form name='form' action='{0}' method='post'>", postbackUrl); sb.AppendFormat("<input type='hidden' name='t' value='{0}'>", value); sb.Append("</form>"); sb.Append("</body>"); sb.Append("</html>"); Response.Write(sb.ToString()); Response.End(); } } Target Site has function to 1. Get authentication parameters. 2. Validate the parameters with shared secret. 3. If the user is valid, then do authenticate and redirect to target page. 4. If the user is invalid, then show errors and return. using System; using System.Web.Security; using System.Text; public partial class _Default : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { if (!IsPostBack) { if (User.Identity.IsAuthenticated) { Response.Redirect("~/Default.aspx"); } } if (Request.Params.Get("t") != null) { string ticket = Request.Params.Get("t"); char[] delimiters = new char[] { ':', ',' }; string[] ssoVariable = ticket.Split(delimiters, StringSplitOptions.None); string ssoHash = ssoVariable[0]; string ssoTime = ssoVariable[1]; string ssoUserName = ssoVariable[2]; DateTime appTime = DateTime.MinValue; int offsetTime = 60; // get this from config or similar try { appTime = DateTime.ParseExact(ssoTime, "yyyyMMddHHmmss", null); } catch { //show error return; } if (Math.Abs(appTime.Subtract(DateTime.Now).TotalSeconds) > offsetTime) { //show error return; } bool isValid = false; string ssoSharedSecret = "58ag;ai76"; // get this from config or similar string hash = FormsAuthentication.HashPasswordForStoringInConfigFile(string.Format("{0},{1},{2}", ssoSharedSecret, ssoTime, ssoUserName), "md5"); if (string.Compare(ssoHash, hash, true) == 0) { if (Math.Abs(appTime.Subtract(DateTime.Now).TotalSeconds) > offsetTime) { //show error return; } else { isValid = true; } } if (isValid) { //Do authenticate; } else { //show error return; } } else { //show error } } } Summary This is a very simple and basic SSO solution, and its main advantage is its simplicity, only needs to add a single page to do SSO authentication, do not need to modify the existing system infrastructure.

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  • Opening a NTFS partition fails with report: Not authorised

    - by Dugi
    Besides lesser errors on 11.10, I ran into a more annoying one: I cannot access NTFS partitions. No matter whether I use nautilus, dolphin, tux commander or archive manager, always does the same thing, could not mount 'disc name': Not authorised' There were several fixes of problems with access to NTFS partitions, but none of them helped. When I used nautilus in sudo mode, the partition looked empty, although when I booted on windows, there were files. It was reported as a bug somewhere. Can anyone help me?

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  • Week in Geek: Microsoft Warns of First Critical Security Flaws in Windows 8 & RT

    - by Asian Angel
    This week’s edition of WIG is filled with news link coverage on topics such as Mozilla Firefox turns 8 and Android turns 5, Windows (File) Explorer is the app that crashes most on Windows 8, Classic Mode (Session) will be dropped from GNOME 3.8, and more. 6 Ways Windows 8 Is More Secure Than Windows 7 HTG Explains: Why It’s Good That Your Computer’s RAM Is Full 10 Awesome Improvements For Desktop Users in Windows 8

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  • Week in Geek: Free Version of Google Apps for Business has been Discontinued

    - by Asian Angel
    This week’s edition of WIG is filled with news link coverage on topics such as Android’s ‘Google Now’ services are headed for Chrome, Microsoft is ready to push Hotmail users to Outlook.com, a 25 GPU setup devours password hashes at up to 348 billion per second, and more. How to Factory Reset Your Android Phone or Tablet When It Won’t Boot Our Geek Trivia App for Windows 8 is Now Available Everywhere How To Boot Your Android Phone or Tablet Into Safe Mode

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  • OpenVPN fails to start automatically

    - by Kaushal Shriyan
    Hi, I have two openvpn site configs. I have configured openvpn in daemon mode and it needs to be restarted automatically while bootup. I am always faced with the situation below. and then i need to restart it manually. Dec 27 16:24:26 kaushal-laptop ovpn-sjc2[1287]: script failed: external program exited with error status: 1 Dec 27 16:24:26 kaushal-laptop ovpn-sjc2[1287]: Exiting Please suggest/guide Thanks

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  • Why are notifications appearing in the invisible black zone above my monitor ?

    - by Capt.Nemo
    I've got two monitors, with the right side one being slightly lower in the display settings. However any notifications I receive from notify-osd (including pidgin, notify-send etc) are sent to the top-most part of the right monitor screen, which results it in being invisible. And here's a pic of my monitor preferences : I'd earlier used the Wallpaper plugin in compiz to stitch my desktops, and then uninstalled compiz-extras. I'm using Ubuntu 11.04 in classic mode.

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  • Should I Adjust the Volume by Software or Hardware?

    - by Jason Fitzpatrick
    You can adjust the your speaker volume in-app, operating system-wide, or by the physical controls on your speaker setup. Which method is best for optimum sound? Today’s Question & Answer session comes to us courtesy of SuperUser—a subdivision of Stack Exchange, a community-drive grouping of Q&A web sites. Our Geek Trivia App for Windows 8 is Now Available Everywhere How To Boot Your Android Phone or Tablet Into Safe Mode HTG Explains: Does Your Android Phone Need an Antivirus?

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  • Building SANE from git-source produce backend missmatch on 12.04 even if built locally

    - by deinonychusaur
    It seems to me that with Ubuntu Precise Pangolin it is all but easy to do a proper install of SANE from source (git-repo). I've found other scanning issues trying to find an answer to this, where the output people posted seems to indicate they suffer the same issue (unknowingly). If I run on a fresh install of Ubuntu 12.04 with compiled SANE source from the git I get: $ scanimage -V scanimage (sane-backends) 1.0.24git; backend version 1.0.22 (I basically followed the instructions on http://ubuntuportal.com/2012/02/how-to-get-an-canon-canoscan-lide-100-scanner-to-work-in-ubuntu-11-10linux-mint-12.html since I didn't find any other information making sure that sane was not installed prior to installation.) My primary interest is the epson2-backend. In 1.0.22 it offers the wrong TPU settings for Epson V700 (TPU2-mode wasn't supported in 1.0.22, and the scanner is useless to me if I don't have the TPU2-support). Since if I ask it to enter transparency mode, it shows 1.0.22 behaviour, it implies that the epson2-backend comes from 1.0.22 and not 1.0.24 even though I just built it. If I install SANE with prefix to a local folder and run that version of scanimage it still produces the mismatch. However, on another computer where I installed a custom 1.0.22 build of SANE prior to upgrading to Ubuntu 12.04, I can build and install the same SANE-git locally and have it correctly match backends: $ ./SANE/bin/scanimage -V scanimage (sane-backends) 1.0.24git; backend version 1.0.24 $ scanimage -V scanimage (sane-backends) 1.0.22; backend version 1.0.22 On this computer the 1.0.24 works correctly in finding TPU2 on Epson V700. So what am I missing/doing wrong? (And I want to replace 1.0.22 with 1.0.24 for the whole system, the local build was just debugging.) Any help would be much appreciated. Edit 1: Just tried compiling SANE using this instruction on Ubuntu 10.04 and it worked like a charm. However, when I upgraded to 12.04 (really would like to run 12.04), SANE was downgraded to 1.0.22. When trying the same set of instructions on 12.04 I was still out of luck -- the backend missmatch was there again (and I do have libusb-dev installed) Edit 2: I updated to Ubuntu 12.10 which now has the 1.0.23 SANE drivers. I haven't dared trying to compile from source on 12.10 since 1.0.23 is good enough for me. This is just a work-around and I would still like to know what's up with Ubuntu 12.04.

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  • iwconfig, iw not displaying wireless information

    - by Srivatsa Kanchi
    after fresh install to 12.10, the wireless information is not shown by both iwconfig and iw. The wireless sets up successfully and able to connect This is what i get $ iwconfig wlan0 wlan0 IEEE 802.11abgn ESSID:off/any Mode:Managed Access Point: Not-Associated Tx-Power=14 dBm Retry long limit:7 RTS thr:off Fragment thr:off Power Management:off $ iw wlan0 link Not connected. $ uname -a Linux srivatsa-ThinkPad-T61 3.5.0-18-generic #29-Ubuntu SMP Fri Oct 19 10:26:51 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

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