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目前顯示的是 2012的文章

GOES-13 returns to service

The trouble stemmed from a motor vibration , which caused a lubricant buildup that obstructed the spinning motion of the filter wheel in the sounder . A team of engineers from NOAA, Boeing and ITT suppressed the vibration, the filter wheel restarted and is running smoothly, with improved performance The GOES-13 satellite, which provides regular weather images every 15 minutes, is a valuable tool for meteorologists and climatologists. The geostationary satellite has been providing coverage of the U.S. East Coast since April 14, 2010. Not only can it produce satellite images both in the visible and infrared channels, but it can also take in and relay back a lot of meteorological information that actually is used in our various weather models, such as the Global Forecast System (GFS) and the European Centre for Medium-Range Weather Forecasts (ECMWF). These are valuable tools that NASA/NOAA use to monitor our entire weather and climate across the globe. GOES-14 – the...

GPS meterology

What is GPS meterology? Global Positioning System (GPS) Meteorology is the application of GPS data to the monitoring and analyses of atmospheric conditions. Atmospheric monitoring can be done by both ground-based and space-based GPS applications. GPS satellites transmit radio signals that can be inverted to measure atmospheric profiles of refractivity. The refractivity profile can be transformed to profiles of tropospheric humidity given a temperature profile. Ground-based GPS receivers at fixed locations can be used to gather data that can be used to determine integrated Precipitable Water Vapor (PWV). Atmospheric scientists have shown that GPS-determined PWV observations can significantly improve weather forecasting accuracy. Why is measurement of PWV important?...

bone repair material making using 3D printing

PLGA/TCP/Icaritin, the composite material, provides cost-effective way to bone fracture and repair. cuhk ScienceDirect

GNSS Connector software for Geoexplorer GeoXR

click here GeoExplorer GeoXR product page

Trimble Net R9 - Reference Receiver with GNSS

CORS C ontinuous O peration R eference S ite real time processing, continuous absolute positioning ( X, Y, Z). realtime RTK distance between each station is usually less than 20 km. Trimble can be upto 50 km due to interference due to ionosphere and high sunspot activity, interference from mobile phone base stations, mobile base station cars only Trimble has an autoswitch competitor : Leica Spider, can only do manual switch output data frequency: up to 50 Hz military grade ( normally 5, 10 to 20 Hz) application: 國家陸態網. to detect minute land movement , due to eargththqqiiale eartjhquake. or 大陸板塊移動 seismic movement choke ring antenna - has high sensitivity against multi path interference

ea email setup

1. add mail account 2. user info 3. incoming and outgoing servers info, click the bottom box"要求身份驗証"  ,then "設置" 4. info of "登錄方式" 5. "高階" tab >>port 2525 for outgoing mail

multimedia streaming: technology and how to

a few links lecture video from Washington University: Multimedia Networking digplanet : Learn and talk about Real Time Streaming protocol notes on real server essay on RTSP real time streaming protocol How Wisconsin U puts it to practice pearltrees blog on how to setup a HTTP live streaming server in chinese Flash video stream recording how-tos streaming media hosting service provider powerpoint from berkeley U

3D printer

starting from reprap a few years ago, 3D printing has been evolving at full speed. Most that we've been talking is based on fused filament, by using filaments of ABS or PLA. From one research, the market is mainly dominated by MakerBot, RepRap, Objet and other long time industrial makers, eg Stratasys, zCorp and some others. make magazine , wired , tested has been talking a lot Bre Pettis of MakerBot also talked on TED 2012 MakerBot TV on youtube: What is 3D printing from www.3dprinter.net Every thing you want to know about 3d additive printing

UNI-T UT2102C softwares

the softwares are not available for download from the official site. After googling, here is one site in cz: tipa from cz has developed a simple "virtual instrument" software for linux QT3. written in Python. In his download site, the USB driver can also be found. the driver will install in windows as libusb-win32 device ZmaTkar However, this device is not working with UNI-T's "virtual instrumetn" software. Right now, I can only use the serial port to communicate with the UNI-T's software...

a flying plane in google map

A plane found somewhere near Ting Kau, and another unknown shadow: 22.374444,114.086963 檢視較大的地圖 I think the shadow belons to this plane, however, the photo is shot from satellite 3 times in each primary colour : red green and blue. Maybe due to parallax , the shadows are not overlapping

unmanned space vehicle for delivery

NASA / ISS is now trying out SpaceX's Dragon. It's one of ways to replace the role of space shuttle, which were now retired. They use the robotic arm CanadARM to "catch" the Dragon, when it is within 2 km range of the space station. It's a very KISS approach to solve the problem. When compared with China's ShenZhou 8 type of head-to-head dockiing method, this "catch" method is safer, when there's some mishappenings. ??? ( is it real ?) It's also low tech enough for commercialisation too. SpaceX successfully kicked off the rocket called Falcon 9 on 22 May, 2012 and attached to ISS ( International Space Station) on 25 May animation  soyuz docking explained   german instruments onboard   shenzhou 8 launch and docking

Security updates for Debian / Ubuntu

In view that now malware threats is extending to other non-Windows platform, like recently on MAC OS X, the flashback trojan, it should be on higher alert to linuxes too. For Ubuntu, besides using Update Manager to do it for you, one of the way is to get security updates, eg from Debian Security . >>> This won't work. As you couldn't get trust certificates so that the patch be applied to Ubuntu. You need to use Ubuntu Security Update Simply add a line like this to your apt: deb http://security.debian.org/ squeeze/updates main contrib non-free You can use apt to easily get the latest security updates. This requires a line such as deb http://security.debian.org/ squeeze/updates main contrib non-free in your /etc/apt/sources.list file. Then execute apt-get update && apt-get upgrade to download and apply the pending updates.  instead, get automatic security update for Ubuntu Go to Update Manager,...

Ngong Ping 360 investigation report

This haul-rope transport system is one of the most challenging project in the world, in terms of scale, length, and shape of travel. The investigation from EMSD pinpoints it is 1) a mechanical failure 2) abnormal vibration at bullwheel No. 3 and No. 4 3) this abnormal vibration triggers the vibration sensor, and cause emergency stop of the system cause of failure wear and tear of linings ( rubber ) at the bullwheel upper raceway of inner bearings : spalling             pits and dents in running element : lower raceway - outer bearing : corroded metal fragments ( Hmmm, may have been running without lubrication and high temperature....) high moisture content of lubricant The remedial actions include: 1) replace all bull-wheel bearings 2) enhance the vibration monitoring system of all bull-wheel bearings to capture data on an ongoing basis, 3) increase scrutinising frequency to fortnightly. Frankly speaking, ...

zigbee DRF1605H commands

under Ubuntu, you can use Gtkterm  Serial port is 38400,8N1  flow control: none the last byte is the LSB of sum of all the previous 6 bytes eg,  FC(hex) + 00(hex) + 91(hex) +  03(hex) + A3(hex) + B3(hex) = 2E6(hex), so the LSB of 2E6(hex) is E6 (hex) Read PAN ID:                  FC 00 91 03 A3 B3 E6 Read Short Address:      FC 00 91 04 C4 D4 29 Read MAC Address:       FC 00 91 A8 B8 F5 Read the type of node:   FC 00 91 0B CB EB 4E   return: 43 6F 6F 72 64 69 means coordinator   return: 52 6F 75 74 65 72 means router Read the wireless channel no: FC 00 91 0D 34 2B F9

How to detect USB Serial port in Ubuntu

first use lsusb command to find: Mar 25 09:11:26 joelinux kernel: [ 1803.128054] usb 6-1: USB disconnect, address 3 Mar 25 09:11:26 joelinux kernel: [ 1803.128239] pl2303 ttyUSB0: pl2303 converter now disconnected from ttyUSB0 Mar 25 09:11:26 joelinux kernel: [ 1803.128263] pl2303 6-1:1.0: device disconnected Mar 25 09:11:30 joelinux kernel: [ 1807.632517] usb 6-1: new full speed USB device using uhci_hcd and address 4 Mar 25 09:11:30 joelinux kernel: [ 1807.794123] pl2303 6-1:1.0: pl2303 converter detected Mar 25 09:11:30 joelinux kernel: [ 1807.806180] usb 6-1: pl2303 converter now attached to ttyUSB0 so you can be sure that kernel has detected the USB port. Next, detach and re-attach your USB serial device, and look in syslog 1)by System > Administration > System Log Viewer > syslog or 2) in terminal >>tail /var/log/syslog Mar 25 09:11:26 joelinux kernel: [ 1803.128054] usb 6-1: USB disconnect, address 3 Mar 25 09:11:26 joelinux kernel: [ 1803.12...

Chinese year cycle and the Sun

It's well known that Chinese has the 12 Shenxiao ( 生肖 ), whereas for the solar activity is around 11 to 12 years. This year is near the max solar activity( now is year of the Dragon), and cause massive eruptions called CME ( coronal mass eruptions ). When these erupted material reach the Earth, this will cause the electro-magnetic storm.  How will this affect our daily lives?  Are chinese aware of such solar activities, and therefore set the chinese zodiac as 12 years?

X-37B orbital test vehicle

This experimental vehicle has been quietly in space for a year. USAF has 2 of these unmanned re-launchable spacecraft, and this one is second one. The craft launched aboard an Atlas 5 rocket. This week marked the one-year anniversary of the spacecraft orbiting the planet performing a still secret mission. So far, the USAF has only said that the craft is performing top-secret experiments. We have no indication of when the X-37B might return to earth. X-37B number one spent 224 days orbiting the planet before landing on December 3, 2010 at Vandenberg Air Force Base. Amateur astronomers have noted that the second X-37B is in an orbit that is very similar to US spy satellites. Some think the USAF may be using the spacecraft to keep certain countries under close scrutiny. General Characteristics Primary Mission : Experimental test vehicle Prime Contractor : Boeing Height: 9 feet, 6 inches (2.9 meters) Length : 29 feet, 3 inches (8.9 meters) Wingspan : 14 feet, 1...

running arduino in Ubuntu: no rxtx

In short, it's due to an open bug in Sun Java. As it is  not open sourced, so you can only wait for them to fix it. It's documented in ubuntu launchpad bugslist 1) don’t use sun-java but default-jre instead. This bug is actually a known bug in sun-java. ( bug #325506 ) 2) add export LD_LIBRARY_PATH=/usr/lib/jni to your .bashrc, the .deskop file (in /usr/share/desktop), or on the command line before starting arduino 3) add the new package (instructions are above). link