benefits of IT

For an organization to improve its business process using technology, an IT department is mandatory for management and support of the infrastructure.

An IT department is required for these areas of technology to provide value to the business, because maintenance tasks must be performed by technically competent staff.

		End-User Technical Support
		Desktop Management
		Network Management
		Voice and Data Communications
		Business Applications
		Strategic Technology Planning
		Project Management

Besides using technology efficiently, an IT department will also provide a business with lower costs, higher productivity and higher efficiency in other areas. The IT department does this by:

			Avoids losing revenues
				Lost sales from customers being unable to make purchases
			Decreases costs
				Payroll for employees being idle
				Paying a technician to fix the problem
			Increases productivity because employees will spend less time idle
			Increases efficiency by assuring that persons handling technology issues are knowledgeable in the area
			Increases productivity by allowing employees to focus on core competencies rather than technology issues
			Reduces risk of financial, technological and data losses caused by disasters
			Increases return on investment (ROI) and business value realized from technology projects
			Improves equipment efficiency with planned maintenance activities

Types of technology

To many of us, the term technology conjures up visions of things such as computers, cell phones, spaceships, digital video players, computer games, advanced military equipment, and other highly sophisticated machines. Such perceptions have been acquired and reinforced through exposure to televised reports of fascinating devices and news articles about them, science fiction books and movies, and our use of equipment such as automobiles, telephones, computers, and automatic teller machines.

While this focus on devices and machines seems to be very prevalent among the general population, many educators also hold a similar perspective. Since Pressey developed the first teaching machine in 1926 (Nazzaro, 1977), technology applications in public schools and post-secondary education institutions have tended to focus on the acquisition and use of equipment such as film projectors, audio and video tape recorders, overhead projectors, and computers.

Since the early 1960s, however, a trend has emerged that is changing the way we perceive technology in education. At that time, educators began considering the concept of instructional technology. Subsequently, after considerable deliberation, a Congressional Commission on Instructional Technology (1970) concluded that technology involved more than just hardware. The Commission concluded that, in addition to the use of devices and equipment, instructional technology also involves a systematic way of designing and delivering instruction.

With the rapid development of microcomputer technology, increased research on instructional procedures, and the invention of new devices and equipment to aid those with health problems, physical disabilities, and sensory impairments, the latter third of the 20th century has borne witness to a very dramatic evolution. The current perspective is a broad one in which six types of technology are recognized: the technology of teaching, instructional technology, assistive technology, medical technology, technology productivity tools, and information technology (Blackhurst & Edyburn, 2000).

TECHNOLOGY OF TEACHING

The technology of teaching refers to instructional approaches that are very systematically designed and applied in very precise ways. Such approaches typically include the use of well-defined objectives, precise instructional procedures based upon the tasks that students are required to learn, small units of instruction that are carefully sequenced, a high degree of teacher activity, high levels of student involvement, liberal use of reinforcement, and careful monitoring of student performance.

Instructional procedures that embody many of these principles include approaches such as direct instruction (Carnine, Silbert, & Kameenui, 1990), applied behavior analysis (Alberto & Troutman, 1995; Wolery, Bailey, & Sugai, 1988), learning strategies (Deshler & Schumaker, 1986), and response prompting (Wolery, Ault, & Doyle, 1992). Most often, machines and equipment are not involved when implementing various technologies of teaching; however, they can be, as will be seen later.

MEDICAL TECHNOLOGY

The field of medicine continues to amaze us with the advances constantly being made in medical technology. In addition to seemingly miraculous surgical procedures that are technology-based, many individuals are dependent upon medical technology to stay alive or otherwise enable people to function outside of hospitals and other medical settings. It is not uncommon to see people in their home and community settings who use medical technology.

For example, artifical limbs and hip and knee implants can help people function in the environment. Cochlear implants can often improve the hearing of people with auditory nerve damage. Some devices provide respiratory assistance through oxygen supplementation and mechanical ventilation. Others, such as cardiorespiratory monitors and pulse oximeters are used as surveillance devices that alert an attendant to a potential vitality problem. Nutritive assistive devices can assist in tube feeding or elimination through ostomies. Intravenous therapy can be provided through medication infusion and kidney function can be assumed by kidney dialysis machines (Batshaw & Perret, 1992). In addition to keeping people alive, technologies such as these can enable people to fully participate in school, community, and work activities.

GSM Technology

What is GSM?

GSM (Global System for Mobile communications) is an open, digital cellular technology used for transmitting mobile voice and data services. GSM differs from first generation wireless systems in that it uses digital technology and time division multiple access transmission methods. GSM is a circuit-switched system that divides each 200kHz channel into eight 25kHz time-slots. GSM operates in the 900MHz and 1.8GHz bands in Europe and the 1.9GHz and 850MHz bands in the US. The 850MHz band is also used for GSM and 3GSM in Australia, Canada and many South American countries. GSM supports data transfer speeds of up to 9.6 kbit/s, allowing the transmission of basic data services such as SMS (Short Message Service). Another major benefit is its international roaming capability, allowing users to access the same services when travelling abroad as at home. This gives consumers seamless and same number connectivity in more than 210 countries. GSM satellite roaming has also extended service access to areas where terrestrial coverage is not available.

Did you know that you can be instantly contactable on your usual number in over 100 countries world wide, when you travel with your GSM phone using your own number?

The major advantage of GSM technology is that it allows you to use your GSM phone when you travel outside your own country or region. This is known as roaming.

Roaming is the ability to use your own GSM phone number in another GSM network. You can roam to another region or country and use the services of any network operator in that region that has a roaming agreement with your GSM network operator in your home region/country.

A roaming agreement is a business agreement between two network operators to transfer items such as call charges and subscription information back and forth, as their subscribers roam into each other's areas.

General Packet Radio Services (GPRS)

- General Packet Radio Services (GPRS) is a packet-based wireless communication service that promises data rates from 56 up to 114 Kbps and continuous connection to the Internet for mobile phone and computer users. The higher data rates allow users to take part in video conferences and interact with multimedia Web sites and similar applications using mobile handheld devices as well as notebook computers. GPRS is based on Global System for Mobile (GSM) communication and complements existing services such circuit-switched cellular phone connections and the Short Message Service (SMS).

In theory, GPRS packet-based services cost users less than circuit-switched services since communication channels are being used on a shared-use, as-packets-are-needed basis rather than dedicated to only one user at a time. It is also easier to make applications available to mobile users because the faster data rate means that middleware currently needed to adapt applications to the slower speed of wireless systems are no longer be needed. As GPRS has become more widely available, along with other 2.5G and 3G services, mobile users of virtual private networks (VPNs) have been able to access the private network continuously over wireless rather than through a rooted dial-up connection.

GPRS also complements Bluetooth, a standard for replacing wired connections between devices with wireless radio connections. In addition to the Internet Protocol (IP), GPRS supports X.25, a packet-based protocol that is used mainly in Europe. GPRS is an evolutionary step toward Enhanced Data GSM Environment (EDGE) and Universal Mobile Telephone Service (UMTS).

The Great Technology War: LCD vs. DLP

Introduction

If you are new to the world of digital projectors, you won't have to shop around the market very long before discovering that "LCD" and "DLP" somehow refers to two different kinds of projectors. You might not even know what LCD and DLP are before asking the obvious question "which one is better?"

The answer is simple. Sort of. LCD and DLP each have unique advantages over the other. Neither one is perfect. So it is important to understand what each one gives you. Then you can make a good decision about which will be better for you.

By the way, there is a third very significant light engine technology called LCOS (liquid crystal on silicon). It is being developed by several vendors, most notably JVC and Hitachi. Several outstanding home theater projectors have been manufactured with this technology, and JVC's LCOS-based DLA-SX21 is currently on our list of Highly Recommended Home Theater Projectors. However the discussion of LCOS technology is beyond the scope of this article. For more on LCOS click here.

The Technical Differences between LCD and DLP

LCD (liquid crystal display) projectors usually contain three separate LCD glass panels, one each for red, green, and blue components of the image signal being fed into the projector. As light passes through the LCD panels, individual pixels ("picture elements") can be opened to allow light to pass or closed to block the light, as if each little pixel were fitted with a Venetian blind. This activity modulates the light and produces the image that is projected onto the screen.

DLP ("Digital Light Processing") is a proprietary technology developed by Texas Instruments. It works quite differently than LCD. Instead of having glass panels through which light is passed, the DLP chip is a reflective surface made up of thousands of tiny mirrors. Each mirror represents a single pixel.

In a DLP projector, light from the projector's lamp is directed onto the surface of the DLP chip. The mirrors wobble back and forth, directing light either into the lens path to turn the pixel on, or away from the lens path to turn it off.

In very expensive DLP projectors, there are three separate DLP chips, one each for the red, green, and blue channels. However, in DLP projectors under $20,000, there is only one chip. In order to define color, there is a color wheel that consists of red, green, blue, and sometimes white (clear) filters. This wheel spins between the lamp and the DLP chip and alternates the color of the light hitting the chip from red to green to blue. The mirrors tilt away from or into the lens path based upon how much of each color is required for each pixel at any given moment in time. This activity modulates the light and produces the image that is projected onto the screen.

The Advantages of LCD Technology

One benefit of LCD is that it has historically delivered better color saturation than you get from a DLP projector. That's primarily because in most single-chip DLP projectors, a clear (white) panel is included in the color wheel along with red, green, and blue in order to boost brightest, or total lumen output. Though the image is brighter than it would otherwise be, this tends to reduce color saturation, making the DLP picture appear not quite as rich and vibrant. However, some of the DLP-based home theater products now have six-segment color wheels that eliminate the white component. This contributes to a richer display of color. And even some of the newer high contrast DLP units that have a white segment in the wheel are producing better color saturation than they used to. Overall however, the best LCD projectors still have a noteworthy performance advantage in this area.

LCD also delivers a somewhat sharper image than DLP at any given resolution. The difference here is more relevant for detailed financial spreadsheet presentations than it is for video. This is not to say that DLP is fuzzy--it isn't. When you look at a spreadsheet projected by a DLP projector it looks clear enough. It's just that when a DLP unit is placed side-by-side with an LCD of the same resolution, the LCD typically looks sharper in comparison.

A third benefit of LCD is that it is more light-efficient. LCD projectors usually produce significantly higher ANSI lumen outputs than do DLPs with the same wattage lamp. In the past year, DLP machines have gotten brighter and smaller--and there are now DLP projectors rated at 2500 ANSI lumens, which is a comparatively recent development. Still, LCD competes extremely well when high light output is required. All of the portable light cannons under 20 lbs putting out 3500 to 5000 ANSI lumens are LCD projectors.

The Weaknesses of LCD Technology

LCD projectors have historically had two weaknesses, both of which are more relevant to video than they are to data applications. The first is visible pixelation, or what is commonly referred to as the "screendoor effect" because it looks like you are viewing the image through a screendoor. The second weakness is not-so-impressive black levels and contrast, which are vitally important elements in a good video image. LCD technology has traditionally had a hard time being taken seriously among some home theater enthusiasts (understandably) because of these flaws in the image.

However, in many of today's projectors these flaws aren't nearly what they used to be. Three developments have served to reduce the screendoor problem on LCD projectors. First was the step up to higher resolutions, first to XGA resolution (1,024x768), and then to widescreen XGA (WXGA, typically either 1280x720 or 1365x768). This widescreen format is found, for example, on the Sanyo PLV-70 and Epson TW100, (two more products currently on our Highly Recommended list). Standard XGA resolution uses 64% more pixels to paint the image on the screen than does an SVGA (800x600) projector. The inter-pixel gaps are reduced in XGA resolution, so pixels are more dense and less visible. Then with the widescreen 16:9 machines, the pixel count improves by another quantum leap. While an XGA projector uses about 589,000 pixels to create a 16:9 image, a WXGA projector uses over one million. At this pixel density, the screendoor effect is eliminated at normal viewing distances.

Second, the inter-pixel gaps on all LCD machines, no matter what resolution, are reduced compared to what they use to be. So even today's inexpensive SVGA-resolution LCD projectors have less screendoor effect than older models did. And it is virtually invisible on the Panasonic PT-L300U, which is a medium resolution widescreen format of 960x540.

The third development in LCDs was the use of Micro-Lens Array (MLA) to boost the efficiency of light transmission through XGA-resolution LCD panels. Some XGA-class LCD projectors have this feature, but most do not. For those that do, MLA has the happy side effect of reducing pixel visibility a little bit as compared to an XGA LCD projector without MLA. On some projectors with this feature, the pixel grid can also be softened by placing the focus just a slight hair off perfect, a practice recommended for the display of quality video. This makes the pixels slightly indistinct without any noticeable compromise in video image sharpness.

Now when it comes to contrast, LCD still lags behind DLP by a considerable margin. But recent major improvements in LCD's ability to render higher contrast has kept LCD machines in the running among home theater enthusiasts. All of the LCD projectors just mentioned have contrast ratios of at least 800:1. They produce much more snap, better black levels, and better shadow detail than the LCD projectors of years past were able to deliver.

Health Risks due to infrared

Imagine for a moment going about your daily routine without electricity. You probably awoke to an electric clock radio/alarm, showered under warm water supplied via an electric hot water heater, drank a couple of cups of coffee from your automatic electric coffee maker, listened to the weather on the electric powered TV or radio - and the list goes on and on. We live in an electrical environment!

Electricity is all around you and while you cannot see electricity, you can certainly appreciate the results. However, any time electric current travels through a wire, the air, or runs an appliance, it produces an electromagnetic field. It is important to remember that electromagnetic fields are found everywhere that electricity is in use. While researchers have not established an ironclad link between the exposure to electromagnetic fields and ailments such as leukemia, the circumstantial evidence concerns many people.

The evidence also suggests that we need to use some common sense when dealing with electricity. In scientific terms, your body can act as an antenna, as it has a higher conductivity for electricity than does air. Therefore, when conditions are right you may have experienced a small "tingle" of electric current from a poorly grounded electric appliance. As long as these currents are very small there isn't much danger from electric fields, except for potential shocks. Your body, however, also has a permeability almost equal to air, thus allowing a magnetic field to easily enter the body. Unfortunately your body cannot detect the presence of a strong magnetic field, which could potentially do much more harm.

In terms of wireless technology, there are no confirmed health risks or scientific dangers from infrared or radio frequency, with two known exceptions:

1. point-to-point lasers which can cause burns or blindness
2. prolonged microwave exposure which has been linked to cancer and leukemia

Therefore, most health concerns related to electromagnetic fields are due to electricity in our day-to-day use, such as computer monitors and TVs. These dangers, if any, are already in the home and work place, and the addition of wireless technology should not be seen as an exceptional risk. We might be rightfully worried or concerned about the electric power grid two blocks from our home or school, but at the same time, we sleep each night with our head only a few feet from an AC powered clock radio, which may be far worse due simply to proximity. We might be also be worried about the magnetic radiation or magnetically induced electrical fields which surround us from the fluorescent light fixtures and high voltage, high frequency lighting we sit under at work and at home. The real danger, however, is that we normally position ourselves too close to the electromagnetic field source (computer monitor, TV, etc.). Remember that the strength of the electromagnetic field (EMF) decreases as the square of the distance from the field source. Therefore, if we are 2 meters away from the source, the EMF strength is reduced to 1/4, but if we move 8 meters away from the source, the EMF strength is reduced to 1/64 of its original strength.

Safety

There are a few things you can do to make your home and work environment a safer "electronic" place. The first thing to consider when possible is to buy Federal Communications Commission (FCC) Class B rated equipment. The FCC classifies computer equipment for its potential to generate radio frequency pollution. Class B emits less radio frequency pollution than Class A, and is more suitable for the residential environment. Unfortunately, while Class B emits less radio frequency pollution, there is nothing in the FCC classes regarding magnitude or level of the pollution.

Other potential risks exist in high voltage (e.g. power) components such as display monitors, computer power supplies, etc. If possible select low power units, shielded units, etc. and operate them at lower resolutions. For example, VGA resolution has a lower refresh scan rate than SVGA, and thus lower magnetic field pollution. If you are adding internal cards to your computers, don't tamper with the computer by removing any internal shielding, covers, etc. Any metal shielding inside your computer was probably put there for a purpose, although to you it may look like a harmless spacer!

If you are really concerned, you can purchase formal safety testing tools or hire a consultant to do formal testing for EMF. There are also cheap tools you can utilize to test for the presence of strong radio or magnetic fields. For example, the presence of a strong magnetic field will deflect a compass needle from pointing north, or the presence of a strong radio frequency field will distort an AM radio's ability to clearly tune in a station. Simple tools like these can be used to screen for strong EMF.

Security

Electromagnetic frequencies currently have little legal status for protection and as such, can be freely intercepted by motivated individuals. This doesn't mean wireless transmission is easily breached, as security varies by the type of wireless transmission method. As presented earlier in the advantages and disadvantages of infrared versus radio frequency transmission, what might be considered an advantage to one method for transmission could turn out to be a disadvantage for security. For example, because infrared is line-of-sight it has less transmission range but is also more difficult to intercept when compared to radio frequency. Radio frequency can penetrate walls, making it much easier to transmit a message, but also more susceptible to tapping.

A possible solution to security issues will likely be some form of data encryption. Data encryption standards (DES) are also being quickly developed for the exchange of information over the Internet, and many of these same DES will be applied to wireless technology.

An Introduction to Infrared Technology

As next-generation electronic information systems evolve, it is critical that all people have access to the information available via these systems. Examples of developing and future information systems include interactive television, touchscreen-based information kiosks, and advanced Internet programs. Infrared technology, increasingly present in mainstream applications, holds great potential for enabling people with a variety of disabilities to access a growing list of information resources. Already commonly used in remote control of TVs, VCRs and CD players, infrared technology is also being used and developed for remote control of environmental control systems, personal computers, and talking signs.

For individuals with mobility impairments, the use of infrared or other wireless technology can facilitate the operation of information kiosks, environmental control systems, personal computers and associated peripheral devices. For individuals with visual impairments, infrared or other wireless communication technology can enable users to locate and access talking building directories, street signs, or other assistive navigation devices. For individuals using augmentative and alternative communication (AAC) devices, infrared or other wireless technology can provide an alternate, more portable, more independent means of accessing computers and other electronic information systems.

In this presentation/paper, an introduction to wireless communication in general is first presented. A discussion specific to infrared technology then follows, with advantages and disadvantages of the technology presented along with security, health and safety issues. The importance of establishing a standard is also discussed with relevance to the disability field, and future uses of infrared technology are presented.

Wireless Communication

Wireless communication, as the term implies, allows information to be exchanged between two devices without the use of wire or cable. A wireless keyboard sends information to the computer without the use of a keyboard cable; a cellular telephone sends information to another telephone without the use of a telephone cable. Changing television channels, opening and closing a garage door, and transferring a file from one computer to another can all be accomplished using wireless technology. In all such cases, information is being transmitted and received using electromagnetic energy, also referred to as electromagnetic radiation. One of the most familiar sources of electromagnetic radiation is the sun; other common sources include TV and radio signals, light bulbs and microwaves. To provide background information in understanding wireless technology, the electromagnetic spectrum is first presented and some basic terminology defined.

The electromagnetic spectrum classifies electromagnetic energy according to frequency or wavelength (both described below). As shown in Figure 1, the electromagnetic spectrum ranges from energy waves having extremely low frequency (ELF) to energy waves having much higher frequency, such as x-rays.

[Figure 1 description: The electromagnetic spectrum is depicted in Figure 1. A horizontal bar represents a range of frequencies from 10 Hertz(cycles per second) to 10 to the 18th power Hertz. Some familiar allocated frequency bands are labeled on the spectrum. Approximate locations are as follows. (Exponential powers of 10 are abbreviated as 10exp.)

10 Hertz: extremely low frequency or ELF.
10exp5 Hertz: AM radio.
10exp8 Hertz: FM radio.
10exp10 Hertz: Television.
10exp11 Hertz: Microwave.
10exp16 Hertz: Infrared (frequency range is below the visible light spectrum).
10exp16 Hertz: Visible Light.
10exp16 Hertz: Ultraviolet (frequency range is above the visible light spectrum).
10exp18 Hertz: X-rays.]

A typical electromagnetic wave is depicted in Figure 2, where the vertical axis represents the amplitude or strength of the wave, and the horizontal axis represents time. In relation to electromagnetic energy, frequency is:

1. the number of cycles a wave completes (or the number of times a wave repeats itself) in one second

2. expressed as Hertz (Hz), which equals once cycle per second

3. commonly indicated by prefixes such as

   a. Kilo (KHz) one thousand
   b. Mega (MHz) one million
   c. Giga (GHz) one billion

4. directly related to the amount of information that can be transmitted on the wave

[Figure 2 description: A sine wave is depicted in the graph in Figure 2. The horizontal axis of the graph represents time, and the vertical axis of the graph represents amplitude. One cycle (or one complete sine wave) is labeled on the graph.]

[Figure 3 description: Graphs of three different sine waves are depicted in Figure 3. The horizontal axis, with values ranging from 0 to 1, represents time in seconds. The vertical axis, with values ranging from -1 to 1, represents arbitrary amplitude. The first graph in the figure depicts a sine wave with a frequency of 1 cycle per second. As shown, the energy wave makes a complete cycle from 0 to its maximum positive value, then through to its maximum negative value, then back to 0. The second graph in the figure depicts a sine wave with a frequency of 2 cycles per second. The sine wave therefore makes 2 complete cycles of moving from 0 to its maximum positive value, through to its maximum negative value, and back to 0, in the same time that the wave in the first graph completes 1 cycle. The third graph in the figure depicts a sine wave with a frequency of 3 cycles per second. The sine wave therefore completes 3 full cycles in the same amount of time that the wave in the first graph completes 1 cycle.]

Figure 3 illustrates energy waves completing one cycle, two cycles and three cycles per second. Generally, the higher the range of frequencies (or bandwidth), the more information can be carried per unit of time.

The term wavelength is used almost interchangeably with frequency. In relation to electromagnetic energy, wavelength is:

1. the shortest distance at which the wave pattern fully repeats itself

2. expressed as meters

3. commonly indicated by prefixes such as

   a. Kilo (km) 10exp3
   b. Milli (mm) 10exp-3
   c. Nano (nm) 10exp-9

4. inversely proportional to frequency

Figure 4 depicts an infrared energy wave and a radio energy wave, and illustrates the two different energy wavelengths. As is expected based on the electromagnetic spectrum, the infrared wave is higher frequency and therefore shorter wavelength than the radio wave. Conversely, the radio wave is lower frequency and therefore longer wavelength than the infrared wave. Anyone who has listened to the radio while driving long distances can appreciate that longer wavelength AM radio waves carry further than the shorter wavelength FM radio waves.

[Figure 4 description: Figure 4 depicts a radio frequency energy wave superimposed upon an infrared energy wave, and illustrates the inverse relationship between frequency and wavelength. The infrared energy wave completes nearly 5 and a half cycles in the time that the radio frequency wave completes 2 cycles. The wavelengths of the infrared wave and the radio wave are labeled, and the infrared wavelength is less than half the wavelength of the radio wave.]

Other terms commonly used in describing wireless communication include transmitter, receiver, and transceiver. In any type of wireless technology, information must be sent (or transmitted) by one device and captured (or received) by another device. The transmitter takes its input - a voice or stream of data bits for example, creates an energy wave that contains the information, and sends the wave using an appropriate output device. As an example, a radio transmitter outputs its energy waves using an antenna, while an infrared transmitter uses an infrared light- emitting diode (LED) or laser diode. The electromagnetic energy waves are captured by the receiver, which then processes the waves to retrieve and output the information in its original form. Any wireless device having the circuitry to both transmit and receive energy signals is referred to as a transceiver. Depending on the communication protocol being used, a device may be capable of only transmitting or receiving information at one time, or it may be capable of both transmitting and receiving information at the same time.

The above described terminology is relevant in all forms of wireless communication, regardless of the band of electromagnetic energy (radio, infrared, etc.) being used. Although radio and ultrasound waves have frequent application in wireless communication, the remainder of the presentation/paper is devoted more specifically to infrared (IR) technology. Infrared technology is highlighted because of its increasing presence in mainstream applications, its current and potential usage in disability-related applications, and its advantages over other forms of wireless communication.