Show of 10-24-2009

  • Email and Forum Questions
    • Email from John: I have a collection of over 200 CDs and want to store them on a hard drive and distribute music to the house. How should I store the CDs so as not to lose quality? Thanks, John.
    • Tech Talk Answers: Excellent questions. Let’s look at audio quality first. I assume that you want to maintain CD quality for your stereo system. CD quality is an audio stream that has been sampled at 44.1 kHz with 16 bit accuracy. The highest frequency that can be heard by the human ear is around 20 kHz. The sampling rate is slightly more that twice this maximum frequency. 16 bit accuracy take the amplitude and maps it to 65, 536 levels. This quality required approximately 5 MB per minute per channel (44,100 x 65,536. Thus one minute of uncompressed stereo requires around 10 MB per minute.
      • Dominant compressed, lossy formats are MP3 (MPEG, Audio Layer 3), AAC (Advanced Audio Coding), and WMA (Windows Media Audio). They achieve about a 10 to 1 compression and provide “near” CD quality (assuming 256 kbps). This format is used for most audio players and for transferring songs via the Internet. AAC is used by Apple and WMA by Microsoft. AAC and WMA can are available with or without DRM. MP3 is the preferred file format because it never has DRM.
      • Dominant uncompressed, lossless formats are AIFF (Audio Interchange File Format) and WAV (WAVeform audio format). Both are open standards. AIFF is used by Apple and WAV by Microsoft and IBM. Both of these require 10 MB per minute for stereo.
      • Dominant compressed, lossless formats are Apple Lossless, WMA Lossless (Windows Media Lossless), and FLAC (Free Lossless Audio Codec). They achieve at most a 2 to 1 compression ratio, depending of the type of music.
    • For archival, I would use either AAA Lossless or WMA lossless. Use FLAC if an open source format is important to you. All are widely supported by media players.
    • What about your hard drive? The average song is 3.66 minutes and will take approximately 36 MB as a WAV or AIFF. 1,000 songs would take 36 GB. I would recommend Network Attached Storage device with two 500 GB hard drive operating in Raid 1 (mirrored drives). Such a device would be around $350 and could be plugging into your Wi-Fi router and be available to all machines on the network.
    • Email from Joan: Dear Dr. Shurtz. I am considering a new laptop with Windows 7. I don’t know whether to get a 32-bit or 64-bit operating system. What do you think?Joan from Rockville
    • Tech Talk Answers: Unless you need lots of RAM, I would opt for the 32-bit operating system for now. Not all programs are available for a 64-bit operating system. For instance, our VPN clients only run on 32-bit OS.
    • Since a 32-bit operating system can address only 4 GB, getting more RAM with a 32-bit system is useless. 4 GB is more than most people need.
    • Why would you need more? If you are going to run VMWare with multiple operating systems simultaneously. Each OS is going to need at least 1 GB, so 8 or 16 GB could make sense. You might need more RAM if you are going to be manipulating a hugh database and want to have all of the data in RAM for fast searching and manipulation. If you computer is going to used as a server with multiple users, more than 4GB of RAM is useful.
  • Profiles in IT: Norman Abramson
    • Norman Abramson developed Alohanet, the first wireless network used for computer communication. The techniques used in Alohanet were the inspiration for Ethernet.
    • Norman Abramson was born April 1, 1932 in Boston, Massachusetts
    • He received a BA in Physics from Harvard University in 1953, a MA in Physics from UCLA in 1955, and a PhD in EE from Stanford University in 1958.
    • He worked as a research engineer in the Hughes Aircraft Company until 1955
    • He took a position as an associate professor of electrical engineering at Stanford after graduating in 1958 until 1966.
    • His passion for surfing brought him to Hawaii in 1966, where he became a professor of electrical engineering and computer science at the University of Hawaii.
    • Abramson describes it as “The only university in the world where I could teach a class 15 minutes after riding in on a wave at Waikiki.”
    • The move to Hawaii set the stage for Abramson’s most profound professional achievements, namely the development of the Aloha networking protocols and the implementation of Alohanet in the late 1960s.
    • Hawaii’s universities are scattered throughout the islands, and Abramson wanted to develop a network that would let the universities share data wirelessly.
    • He obtained funding from ARPA (Advanced Research Projects Agency).
    • The idea was to use low-cost amateur radio-like systems to create a computer network linking the far-flung campuses of the University.
    • By 1970, Abramson had developed a working design that used a revolutionary concept, called packet switching, to transmit data via radio waves.
    • Transmitted data was divided up into discrete chunks of data called packets, which were streamed to a receiver station where the packets were reassembled.
    • The beauty of the design was that if a receiver reported that a packet was missing, the transmitter was able to simply resend the packet instead of the entire transmission.
    • The original implementation of this technology was very inefficient because the original data streams shared the same radio frequency which led to packet collisions.
    • ALOHA was important because it used a shared medium for transmission. This revealed the need for more modern medium access control schemes such as CSMA/CD, used by Ethernet.
    • Alohanet inspired Bob Metcalf to propose Ethernet in his Harvard dissertation and implement it shortly thereafter at Xerox PARC.
    • Researchers at ARPA picked up on the basic idea and evolved it into the Ethernet standard to create ARPANet, the precursor to the Internet.
    • He worked as professor of electrical engineering, professor of information and computer science, and Chairman of the Department of Information and Computer Science at the University of Hawaii between 1966 and 1995.
    • In 1994 he founded Aloha Networks, a California-based company specializing in wireless communication technology, where he served as CEO and CTO.
    • An IEEE Life Fellow, he holds eight patents and has published more than 50 papers.
    • In 2007, he received the IEEE Alexander Graham Bell Medal “For contributions to the development of modern data networks through fundamental work in random multiple access”
  • Windows 7 Released Finally
    • An upgrade version of Windows 7 Home Premium costs $120
    • A full version costs $200.
    • Reviews are good so far.
    • Not a resource hog like Vista. Runs on low end laptops.
    • Laptop sales spikes after the release of Windows 7 on October 22.
    • Upgrade path
      • No upgrade from XP possible.
      • You must upgrade to Vista, then Windows 7.
      • A clean install is preferred, but more difficult to accomplish.
    • It you have a favorite application that runs on XP and won’t run on Windows 7, you can run an XP virtual machine for that application.
    • Upgrading from Vista Home Premium to Windows 7 Home Premium (or Vista Business to Windows 7 Professional) is reasonably straight forward.
      • Microsoft includes a handy tool called Windows Easy Transfer.
      • This collects all the files, photos, videos and songs, as well as all the program settings, and stores them in one enormous file on the hard-drive.
      • After the installation is completed, running the tool again imports all the individual files and settings.
    • Microsoft has not provided a simple upgrade path for XP users.
      • Users are forced to do a clean install. That means copying all the data on the XP computer to an external storage device, installing Windows 7, copying the data back again, reinstalling all the applications.
      • Before you upgrade from XP to Windows 7, download and install a free copy of Microsoft’s Windows 7 Upgrade Advisor. This will identify any programs or devices on the XP machine that are not compatible with Windows 7.
      • Get a copy of Laplink’s PCmover Windows 7 Upgrade Assistant for around $20.
      • The Laplink tool scans the computer for applications to move and provides a list of boxes to check. It then begins the transfer by creating a file called Moving Van. Copy this file to an external drive.
      • Innstall an upgrade copy of Windows 7 on the computer, choosing Custom rather than Upgrade.
      • When the upgrade is complete, the Laplink tool is reinstalled so it can unload the Moving Van from the external drive.
  • Dumb Idea of the Week Windows 7 Whopper from BK in Japan
    • Availability: one week (7 days)
    • Price: 777 Yuan ($8.55) for first 30 customers (then 1,450 Yuan, $17,10)
    • Seven patties stacked to over five inches in height.
  • Universal phone charger approved
    • A new mobile phone charger that will work with any handset has been approved by the International Telecommunication Union (ITU), a United Nations body.
    • Industry body predicts that 51,000 tons of redundant chargers are generated each year.
    • Currently most chargers are product or brand specific, so people tend to change them when they upgrade to a new phone.
    • The charger has a micro-USB port at the connecting end, using similar technology to digital cameras.
    • It is not compulsory for manufacturers to adopt the new chargers but the ITU says that some have already signed up to it.
    • ITU is planning to launch the universal charger internationally during the first half of 2010.
  • Technology Application of the Week: The DuoFertility Device
    • Website: http://www.duofertility.com/
    • It was developed by Cambridge Temperature Concepts, a company spun out of Cambridge University.
    • They have created a device that, they believe, will help women who are experiencing fertility problems to conceive.
    • The device consists of a temperature sensor worn under the arm and a portable reader to collect temperature data.
    • The patch that collects the relevant data is worn on the body beneath the arm.
    • It need only be worn at night, but can be worn the whole time for convenience.
    • It contains a coin-shaped sensor encapsulating two thermometers, a movement detector and a battery. The patch takes the woman’s temperature every few seconds, and uses the difference between the two thermometer readings to determine whether she is naturally warm or is being heated or cooled by her surroundings. The movement detector is there to identify when she is sound asleep.
    • During the day, the wearer uploads the data collected overnight to a display unit, which is the size of a computer mouse and communicates wirelessly with the patch.
    • This tells her whether she has ovulated, based on any rise in her basal body temperature that the patch has noticed.
    • A user can help hone the process of prediction further, if she wishes, by sharing her data. She can plug the device into a computer connected to the internet and send the information it contains to Cambridge Temperature Concepts for analysis. The company combines her data with those uploaded by hundreds of other women so that its algorithms can learn and improve their accuracy in predicting ovulation.
    • Price: £495 – including free shipping and VAT ($807 US)
    • The company is offering a money-back guarantee if pregnancy is not achieved.
    • Approved in most countries. Pending approval in the US.