employees are not trained on the new tools and how it can streamline their work, than they are less likely to best utilize the new software. Implementing enterprise software without staff training virtually guarantees that large chunks of functionality will be lost due to employee ignorance. Staff will become frustrated, avoid using the software when possible and negatively impact the operations bottom line. Training should therefore be a priority
Сduring the implementation period.
Staff members must be trained not only on how to use the software, but the organizational benefits that this new system provides. A process must be put in place that can provide this information, while offering a platform from иwhich employers can address any lingering concerns that employees may have. Let’s face it, change of any kind is a scary thing for most people and there will be those who object. Smart companies, with the help of knowledgeable ERP vendors, can guide employees through this change and help staffбАto realize the enormous benefits that the new system can provide.
Finally, ERP solution providers should offer adequate technical support to guide an enterprise through the first weeks after implementation and address any issues that arise over time. Comprehensive help services should include a telephone hotline, as well as Web and on-site support. These services help to ensure that your company will receive maximum return on its technology investment.
NEW APPROACH TO GENERATING
TRULY RANDOM NUMBERSДMAY IMPROVE INTERNET
SECURITY, WEATHER FORECASTS
A new approach to generating truly random numbers could lead to improved Internet security and better weather forecasts, according to researchers writing in the International Journal of CriticalИComputer-Based Systems.
Random numbers are a critical part of computer and Internet security. They allow websites and browsers to encrypt the data sent between them using a session key. Weather forecasters, climate scientists, economists, and epidemiologists also use random numbers to generate simulated data for their predictive models. Such simulations can test theories of hurricane formation, climate change, and the spread of disease epidemics, for instance.
According to Bernhard Fechner of the University of Hagen, and Andre Osterloh of BTC AG, in Germany, the "quality" of a random number is a measure of how truly random the number is. This quality affects significantly any security or simulation in which it is used. If a so-called random number is not truly random, then someone could predict a security key and crack the Internet encryption on bank accounts, e-commerce sites or secure
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government websites, for instance. Similarly, if the random numbers used in scientific models of the weather, climate, or the spread of disease and economic boom and bust are predictable, then systematic errors will creep into the models and make the predictions unreliable.
Fechner and Osterloh explain that a good random number in computer binary would usually comprise discrete and uniformly distributed ones and zeroes.
СIn such a sequence there is no way to predict what digit will appear next, the
number is thus random. In reality, it is unfeasible to generate a sequence that is totally unpredictable by computational means. Therefore, physical means are used to generate true random numbers.
иcontents of the memory are purely random.
The German team has now developed a true random number generator that uses an extra layer of randomness by making a computer memory element, a flip-flop, twitch randomly between its two states 1 or 0. Immediately prior to the switch, the flip-flop is in a "metastable state" where its behaviour cannot be predicted. At the end of the metastable state, the
predict withбАany degree of certainty the next number in a sequence compared to current random number generators.ДThis could be used to improve everything from climate change models to stock market predictions.
The researchers' experiments with an array of flip-flop units show that
for small arrays the extra layer makes the random number almost twenty
times more "random" than conventional methods. The degree of randomness
possible depends on the size of the array and so a bigger array could be even
more effective. Essentially, this means that the bigger the array the better the
quality of random numbers. As such, it is many times more difficult to
The team adds that the efforts of a cracker attempting to influence the array will be wholly obvious to a simple statistical analysis as – depending on
the type of attack – either the whole array or single elements will be disturbed, whereas these are again selected randomly.ИSo this true random
number generator can protect systems against third-party snooping, potentially making private and sensitive transactions on the Internet more secure.
COMPUTERS
Most people tend to think about computers in terms of the systems that they use at home or at work. Most of the time these are "stand-alone" models, such as desktops, laptops, or notebooks, and sometimes they are wireless devices, such as palm pilots, personal organizers, and third-generation cellular phones that allow access to e-mail and the Internet. Although public health has not yet taken full advantage of these technologies, it is important
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to understand the basics of these technologies in order to visualize their potential uses in the near and long-term future
Initially, the computer was conceived as a device to manipulate numbers and solve arithmetical problems. During its development, it was recognized that a machine capable of manipulating numbers could also be used to manipulate any "symbol" represented in numeric form. An electronic
Сdata processing system (EDPS) involves at least three basic elements: the input entering the system, or source data; the orderly processing that takes place within the system; and the output, or end result. The EDPS has four functional units: the input devices; the central processing unit (CPU); the иstorage, or memory; and the output devices.
The central processing unit (CPU) is the control center of the EDPS, and it has two parts: the "arithmetic/logic unit" (ALU) and the "control unit." The ALU performs operations such as addition, subtraction, multiplication, and division;бАas well as moving, shifting, and comparing data. The control section of the CPU directs and coordinates all the operations of the computer according to the conditions set forth by the stored program. It selects instructions from the stored program and interprets them. It then generates signals and commands that cause other system units to perform certain operations at appropriate times. It controls the input/output units, the arithmetic-logic operations of the CPU, and the transfer of data to and from storage. It acts as a central nervous system, but performs no actual processing operations on data.
Storage Devices. The mainДstorage of a computer—the memory, or internal storage unit – is basically an electronic filing cabinet where each location is capable of holding data and instructions. The storage unit contains four elements: (1) all data being held for processing, (2) the data being processed, (3) the final result of processing until it is released as output, and
(4) all the program instructions while processingИis being carried out. Each location in main storage is identified by a particular address. Using this address, the control section can readily locate data and instructions as needed. The size or capacity of main storage determines the amount of data and instructions that can be held within the system at any one time. In summary, the internal memory is a temporary storage and is called "random access memory" (RAM). There is also a second type of memory, called "read-only memory" (ROM). This memory is fixed; meaning it can be read but cannot be written to, changed, or deleted. There are also secondary memory devices or auxiliary storage, sometimes called "sequential access memory," such as diskettes, hard drives, and magnetic tape. Depending on how often the data will be used these auxiliary devices will be chosen. For example, mass storage devices or certain types of tapes may be used for archival purposes of
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medical records or bank accounts, where certain legal aspects of the data may be required.
Input/Output (I/O) Devices. These are devices that are linked to the computer and can introduce data into the system, and devices that can accept
data after it has been processed. Some examples are: disk storage drives, printers, magnetic tape units, display stations, data transmission units, and the Сold punched card or paper tape. Input devices perform the function of
converting the data from a form that is intelligible to the user to a form that is
intelligible to the computer. Output, on the other hand, is data that has been
processed, (e.g., shown on a display device). In some cases, a printer can
иcontrol-sequenced instructions stored within the memory of the device. Some common forms of storing data today include: floppy disks (used mainly for
readily display the data in an understandable form. In other instances, such as
with a magnetic tape drive, the data is carried as input for further processing
by another device. In this case, the computer retains the data until further
processing takes place. In summary, a digital computer identifies an
ComputerбАSystem. The computer elements described thus far are known as "hardware." A computerДsystem has three parts: the hardware, the software, and the people who make it work. The computer software can
electronic device capable of manipulating bits of information under the
temporary storage); magnetic disks (fixed or removable); and optical disks that can store very large amounts of data. CD-ROM (compact disk— read only memory) devices store the information by means of a finely focused laser beam that detects reflections from the disc. This technology is sometimes referred by the term "write once, read many times" (WORM).
broadly be divided in two categories: systems software and application software or programs. These systems software can be further divided into:
operating systems and programming languages. A computer program is a set of commands (in the form of numeric codes)Иthat is put into the computer's memory to direct its operation. Testing, or debugging, is done to check if a program works properly. The ongoing process of correcting errors and modifying working programs is called software maintenance. The science of software engineering has provided formal methods for writing and testing programs.
DATA PROCESSING, DATA REPRESENTATION
When people communicate by writing in any language, the symbols used (the letters of the alphabet, numerals, and punctuation marks) convey information. The symbols themselves are not information, but representations of information. Data in an EDPS must be expressed symbolically so that the machines can interpret the information presented by humans. In general, the
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symbols that are read and interpreted by a machine differ from those used by people. The designer of a computer system determines the nature and meaning of a particular set of symbols that can be read and interpreted by the system. The actual data that is used by these systems is (or was in the past) presented as holes on punched cards or paper tape, as spots on magnetic tape, as bits (binary digit) or bytes of information in a disk, diskette, CD-ROM, or
Сoptical disk; as magnetic-ink characters; as pixels in display-screen images; as points in plotted graphs; or as communication-network signals.
In many instances, communication occurs between machines. This communication can be a direct exchange of data in electronic form over иcables, wires, radio waves, infrared, satellites or even wireless devices such as cellular phones, pagers, and hand-held personal organizers and/or notebooks. It can also be an exchange where the recorded or stored output of one device or system becomes the input of another machine or system.
In theбАcomputer, data is recorded electronically. The presence or absence of a signal in specific circuitry represents data in the computer the same way that the absence or presence of a punched hole represented data in a punched card. If we think of an ordinary lightbulb being either on or off, we could define its operation as a binary mode. That means that at any given time the lightbulb can be in only one of two possible conditions. This is known as a "binary state." In a computer, transistors are conducting or nonconducting; magnetic materials are magnetized in one direction or in the opposite direction; a switch or relay is either on or off, a specific voltage is either present or absent. These areДall binary states. Representing data within the computer is accomplished by assigning a specific value to each binary indication or group of binary indications. Binary signals can be used to represent both instructions and data; consequently the basic language of the computer is based primarily on the "binary number system."
A binary method of notation is usuallyИused to illustrate binary indications. This method uses only two symbols: 0 and 1, where 0 and 1 represent the absence and presence of an assigned value, respectively. These symbols, or binary digits, are called "bits." A group of eight bits is known as a "byte," and a group of 32 bits (4 bytes) is known as a "word." The bit positions within a byte or a word have place values related to the binary number system. In the binary number system the values of these symbols are determined by their positions in a multidigit numeral. The position values are based on the right to left progression of powers having a base of 2 (20, 21, 22, 23), commonly employed within digital computers. For example, if there are four light bulbs next to each other numbered 4, 3, 2, and 1 and 1 and 3 are "on" and 2 and 4 are "off," the binary notation is 0101.
The system of expressing decimal digits as an equivalent binary value is known as Binary Coded Decimal (BCD). In this code, all characters (64
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