Bao Mei Mei

In ‘History of the Computer – the emergence of Electronics’, we saw how the development of Radar during the second world war led to an understanding of pulse technology. At the same time methods were refined for the calculations required for the ballistic trajectories. From these beginnings, the digital computer was developed.

What is meant by ‘Analog’ and ‘Digital’? A couple of examples will explain the difference. An analog is something which is analogous, obviously, but you may know that an analogous process or function is one that is equivalent, or very similar to another one. An analogy is often used to explain, or to assist the understanding of, some new feature in terms that are understood.

For example a home electric circuit for house wiring to operate a lamp. The supply is controlled by a circuit breaker, when it is available at the outlet where the lamp is plugged. This can be compared to plumbing, where the water supply is controlled by a valve or tap on entering the home, then pipes carry the water to the kitchen, where the supply can be turned on or off by a tap or faucet, and is immediately available. The rate of flow of the water can be controlled, which is analogous to a dimmer on the lamp.

The analogy is not absolutely the same, but aids in the understanding of the electricity supply by someone who knows the plumbing system.

Digital, concerning digits or numbers, refers to the use of numbers to represent all things. As an example, a digital watch uses numbers to indicate the time. The numbers on the face of traditional watch are distributed around the dial, so that the hands pointing to them are analogous to the passage of time. For example the minute hand pointing straight down, half way through the circle of the clock, represents the passing of half an hour. If the hour hand is pointing to the number 3, this indicates 3 hours of the 12 for a complete circuit. When we learnt to tell the time we knew that this was half past three. The digital watch however says 3:30.

Closer to our topic, we can consider the evolution of the gramophone record. The vinyl LP was the standard medium for music recording and playing from the 1950s, tape recordings were also developed in parallel. Both these media use a modulation system, where the amplitude, or strength, of the modulation is proportional, or analogous, to the loudness of the original live singing or playing. This music had been converted by a microphone into an variable electrical signal, analogous to the sound.

With the invention in the 1980s of the Compact Disc, digital techniques were employed to represent the changes in sound levels, by using a sampling pulse to monitor the loudness of the sound. This sampling pulse is used at a high frequency, so that it is not audible, and traces the progress of the sound. The principle is analogous to the movie camera where a sequence of still pictures are shown at a rate of 32 frames per second, so that they appear to show a moving picture. Similarly a TV uses a frame rate of 50 or 60 per second (strictly speaking 25 0r 30 interlaced).

The big advantage of a digital recording and reproduction system (amplifiers etc are also digital) is that, due to the nature of the high frequency pulses, it is possible to copy them exactly when transferring from one medium to another, for example copying a from CD track to compilation cd. With an analogue system there are losses in every transfer, so that a recording on a cassette tape copied from a vinyl lp via a home stereo is noticeably poorer quality than the original.

A computer can also be analog or digital, though the digital type have vastly outgrown the analog. An analog computer might be used in research work, where, for instance a record may be made on a moving chart of the temperature and humidity in a room being air conditioned by a new design air conditioner, the chart could also be a display on screen. Either way, the graph is an analog representation of the temperature and pressure.

Early electronic controls in aircraft were run by a form of analog computer, the amount the ailerons moved was proportional to the movement of the joystick, but not directly proportional. A calculation was performed, which depended on the speed and height of the aircraft, and other factors. The electronic ‘boxes’ involved linear amplifiers and variable response circuits, all fed by sensors from the flight controls etc.

By: Tony Stockill

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Digital technology has taken over the photography world. The benefits are enormous, and advances in cameras and software have quickly overcome the weaknesses of early digital photography. But are modern photographers living up to the potential of their new digital cameras?

As the owner of a gallery, I have many conversations with digital photographers, and I am beginning to see problems, not with digital photography, but with the mindset it seems to have created. And I fear that photography as an art form may be the poorer for it.

One of the benefits that make digital cameras so attractive is the ability to see your results immediately, and delete a photo if you are not happy with it, at zero cost. Gone are the days of waiting until you finish a roll of film, then facing the expense of developing and printing before you get to see your results. With digital photography, you can take a shot without fear: if it doesn’t work, just delete it and try again.

Therein lies my biggest worry about digital photography. The ease with which a photographer can erase a mistake has taken away the need to think about what they are doing. Let’s face it, if you take enough shots of the same subject, eventually you will get it right accidentally.

When film was king, the delay in seeing your results, and the expense connected to each exposure, made it important to get it right, or at least try to do so. When a photographer had to wait until days later to view their results, the opportunity to try again had usually passed. Consequently, it was essential to really learn how to use your camera, and to put creative thought into every exposure.

Of course there was no such thing as a 100% success rate, and plenty of film was wasted, but with concentration and self-discipline, a good film photographer had a right to expect more hits than misses from each roll of film.

These days it is common for someone to want to show me their great new photo, but have to search through the other 50 failed attempts on the memory card to find it. In these cases, the question needs to be asked: was the digital photographer’s eventual success due to good photography or good luck? Moreover, had they learned anything in the process? Presented with the same situation again, would they need to take another 50 photos to get it right the next time?

All too often, if you care about good results, that approach is simply not good enough. In my field of nature photography, many opportunities last no more than a few seconds. Birds fly away, clouds cover the sun, the colors of a sunset change. Fleeting moments are not rare in photography, in fact for some artists they are what photography is all about.

So how does the random snapper cope in these situations? I suspect in many cases the tendency is to blame the bird for flying away, or blame the digital camera for not doing its job properly. The notion that the photo should be easy for someone who knows what they are doing would not compute. Why? Because the sheer convenience of digital photography, with its automatic features and ease of deletion, does not encourage us to actually learn how to use the camera.

Imaging software is part and parcel of the photography industry; I accept that. In fact, to get a truly high-quality print, even the best digital photographer has to do a little ‘work’ on an image from time to time. But computer wizardry should never replace skill with a camera. Sadly, these days many people are relying on software to fix their mistakes, instead of learning to take better photos.

I look at it this way: time spent fixing up a mistake using software ‘ minutes or hours. Time spent getting it right in the first place ‘ about 1/500 second.

If you have a good digital camera, I urge you switch it to manual and learn how to use it. Not much has changed since the old days. The main things you need to learn are still aperture, shutter speed, light and composition. Practice has never been cheaper, and learning from your mistakes has never been easier. All it takes is patience and self-discipline.

Go on ‘ make your camera proud!

By: Andrew Goodall

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The world of digital video editing has been opened up to regular people, instead of specialized video editors, thanks to the world of computers and camcorders. For years, a person who wanted to make one large video from their collection would have to have gone to a professional editor. Thanks to the technology of today, a person can now edit their own videos with the right equipment, which is readily available as long as a person knows what they are looking for in editing software.

The first of the components to making great digital video editing possible is a camcorder with certain features. A person should look for a model that has optical stabilization, which is an option that keeps the image from appearing shaky.

This occurs inside the camera automatically and is a feature that only the higher end models have. For editing purposes, a person will definitely want a camcorder that supports FireWire input and output. If the machine does not have this, then a person is wasting their money and time.

The other main tool that will be needed for editing is a computer. In order to create great videos, the computer needs at least thirty gigs of space available. This will allow a person to create a video that lasts approximately one hour. Also needed will be an eight meg graphics card. Otherwise, the video quality will be dull.

Even the new Macs will be able to create great videos as long as a G4 is present. All a person will need for either a Mac or PC is the right video editing software, such as Adobe Premiere Elements 4 or Pinnacle Studio Ultimate 11, to name only two of the many choices available.

Digital video editing is one arena in which most people have yet to indulge. However, with the right tools, anyone can take part in editing their own home movies. No matter if a person invests in a handycam or a Samsung digital camcorder, the fact that they are taking part in capturing their memories for future generations can prove to be an important aspect of a their life.

By: Mike Selvon

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Kansieo.com

A digital camera can open you up to a whole new world of home renovation. With today’s computer technologies, a talented designer can take digital photos of your rooms and recreate them into rooms that you could only dream of. You can also track your progress throughout the process of renovating and have some great after photos that you will be proud of.

Have you ever painted a room and then wondered a few years later, “What color was that room?” Before and after digital pictures are great for not only those moments of reminiscing, but are excellent for insurance purposes as well. With before and after pictures you are able to compare the changes and renovations that you have made to a home. These pictures can help you to prove the changes you have made and the value those changes have made to your home. There are also several programs that will allow you to store photos of your home and belongings for home inventory purposes. If your house were ever to broken into, burnt or destroyed by a natural disaster. These images could come in very handy for insurance purposes. If you are taking digital photos for this purpose, then you will want to be certain that they are also stored off site at a friend or family member’s home. This will ensure that you will have them in the event that something does happen to your home.

If you are doing your home renovations by yourself, pictures of your progress can be excellent confidence boosters. You will have pictures that you can show to friends and family and say, “Look what I did!” You can also have pictures that show the different stages of design, implementation and the finished product. Many individuals also choose to keep a scrapbook of their home renovations. This is an excellent idea if you are completely renovating and refurbishing an old home. Share the photos on the Internet and show the world the changes that you have made to your home. Who knows, you might be an inspiration to another looking to do home renovations.

If you have digital photos of your home, it can make it very easy for an interior decorator to use your pictures as inspiration. When you have a consultation with the decorator, they can take your pictures and show you things that they would like to change or add. With digital photo software such as Adobe Photoshop, there are various ways a digital photo can be adapted and turned into a completely new room for a renovation idea. You can also have consultations with decorators from different parts of the country, as digital photos can be instantly sent via email to anyone in the world.

Don’t overlook the convenience that digital technology can provide you. Whether you are planning a project, in the process of completing one or just finished, digital photos can be very useful throughout your home renovations.

By: Bill Doane

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Kansieo.com

We live in a world where everything should be written in paper and signed for it to be legal. Titles, diplomas, deeds, last wills and testaments, treaties and contracts all require the paper to be considered effective. When you have business, whether personal or not you would like everything to be crystal clear. This way, you are assured that everything you do won’t lead you to disastrous circumstances. It will also secure that you are advertising your business’s good name in style. That’s why having a high quality printer is a must.

It is true that there are numerous printing services out there however everyone cannot guarantee the high quality printing your business deserves. Some, even if they can provide high quality printing cannot on the other hand provide bulk printing. These drawbacks are a sure way to waste your money, time and effort.

Fortunately there is now a printing service that provides the highest quality of printing and allows printing in bulk. This service provides all kinds of prints such as brochures, flyers, proposals, postcard and the more delicate business product sheets. It is indeed a one stop shop. Because of the elite printing method it uses, it secures that attention is drawn and good impression is made.

With this kind of quality service offer, any business can clearly plan, manage and put into action any visual communications needed. Since it is a top quality printing the business can endorse any product with more confidence achieving top goals in mind.

These high quality printing services are what we call digital printing. This digital printing can help in any printing endeavor such as mailing, digital offset printing, one-to-one marketing and of course, visual designs.

Digital printing is not the only service printing services provide, but it also offers integrated marketing solutions through cross media and direct mailing conveniently allowing businesses to track their success and site prospect customers. No matter the size of the business, whether a corporate or a personal one, this printing service ensures better business ventures.

Aside from the superb prints they produce, these services are served to you by the trained and experienced team members ensuring that whatever you prefer will be met. Needless to say, this service uses high end technology that provides vibrant colors and brilliant black and white contrast.

Patronizing this digital printing through printing services will be the best investment you can make. After all, whatever has your business’s name on it reflects the kind of service and/or products you provide/sell. Last but not the least, this printing service is very much within everyone and anyone’s budget.

By: Geoff Dalton

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Kansieo.com

The days of the conventional doorknob may be numbered. Make way for the digital fingerprint version of this device. It’s science fiction come true. Now available to the general public, it makes for a quick and easy upgrade to your current mechanical door knob. The principle is simple as well. You imprint your fingerprint into the associated memory of the fingerprint knob. Because your fingerprint is unique to you and to no one else, you alone have the possibility to operate the fingerprint door knob.

This capability is important in more ways than one. Because a fingerprint doorknob no longer has a keyhole or similar accessible entrances, it becomes impossible for anyone to pick the lock to gain access to what is behind the door. There’s no chance either of someone guessing or eavesdropping on your secret code, which puts the fingerprint knob one step ahead of most credit and debit cards in the world today.

With new digital technology comes a range of additional functionality. Built in to the micro-processor and memory of the doorknob are functions to allow you keep the door locked permanently during your absence or to allow it to be open during particular times of the day. This functionality also works to allow you to set the door to lock automatically within a short period of you closing it. In this way you no longer have to torture yourself with the question “did I lock the door”, because you know that this was automatically the case.

Installation is typically simple, given a screwdriver. Fingerprint door knobs work with a spring latch mechanism similar to the one that you probably have now. They also typically have the spring-loaded automatic locking feature, where when you pull the door shut, it automatically locks. In past times, this could be very frustrating if you left your keys on the inside. However, with a fingerprint lock, your key is always literally in the end of your finger.

But what if all this sounds a little too technical? Don’t worry; you’ll still be able to buy the good old conventional door knob for quite a while. You may need to spend some time repairing them from time to time, as wear and tear on the door knob and the associated central spindle sometimes causes the doorknob to lose its grip and weakens its effect while turning the spindle. This is often repaired by tightening or replacing the screws that fasten the door knob onto the spindle.

Whether fingerprint or classical, a doorknob is that also an easy way for germs to spread. With anyone and everyone touching the door knob, the risk is understandable. For fingerprint door knobs, there is no real solution as the surface that is sensitive to your fingerprint also harbors germs. However, for the classical doorknobs made of brass or copper, these materials have the interesting property of killing germs and are literally able to disinfect themselves within eight hours. So maybe there’s still a future for the classical doorknob after all.

By: Jennifer Akre

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