Introduction to the microprocessor
Thursday, 12 April 2012Posted by
Crystal
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History
The microprocessor is the combination of solid – state technology development and the advancing computer technologies which came together in the early 1970s. With the low cost of a device and the flexibility of a computer, microprocessor is a product which performs both control and processing functions.
A brief history
The microprocessor of two major technologies; digital computer and solid – state circuits. These two technologies came together in the early 1970s, allowing engineers to produce the microprocessor.
The digital computer is a set of digital circuit controlled by a program that makes it do the job you want done. The program tells the digital how to move process data. It does this by using the digital computer’s calculating logic, memory circuits, and I/O devices. The way the digital computer’s logic circuits are put together to build the calculating logic, memory circuits, and I/O devices is called its architecture.
The microprocessor is like the digital computer because both do computations under programming control.
Figure 1-1 shows the major events in the two technologies as they developed over the last five decades from the days of World War II.
During World War II, scientists developed computers for military use. The latter half of the 1994s, digital computer was developed to do scientific and business work, Electronic circuit technology also advanced during World War II. Radar work increased the understanding of fast digital circuits called pulse circuits. After the war, scientists made great progress in solid-state physics. Scientists at Bell Laboratories invented the transistor, a solid- state device, in 1948.
In the early 1950s, the first general-purpose digital computer appeared. Vacuum tubes were used for active electronic components. They were used to build basic logic circuits such as gates and flip-flops. Vacuum tubes also formed part of the machines built to communicate with the computer – the I/O (input/output) devices. The first digital computers were huge, because the vacuum tubes were hot and required air-conditioning. Vacuum tubes made the early computer expensive to run and maintain. Solid-state circuit technology also made great strides during the 1950s. The knowledge of semiconductors increased. The use of silicon lowered costs, because silicon is much more plentiful than germanium, which had been the chief material for making the early semiconductors. Mass production methods made transistors common and inexpensive.
In the late 1950s, the designers of digital computers jumped at the chance to replace vacuum tubes with transistors.
In the early 1960s, the art of building solid-state computers was divided in two directions. The first direction was building huge solid-state computer by IBM. IT still required large, air-conditioned rooms and very complicated. IT could process large amounts of data. These large data processing systems were used for commercial and scientific application.
The big computer was still very expensive. In order to pay for it had to be run 24 hours a day, 7 days a week. Another direction of development is began building small computers. These minicomputers were not as powerful as their larger relatives, but they were not as expensive either. And they still performed many useful functions. By the early 1960s, the semiconductor industry found a way to put a number of transistors on one silicon wafer. The transistors are connected together with small metal traces. When the transistors are connected together, they become a circuit which performs a function, such as a gate, flip-flop, register, or adder. This new technology created basic semiconductor building blocks. The building blocks or circuit modules made this way are called an integrated circuit (IC).
By the mid-1960s, the technology of ICs pushed to develop low-cost manufacturing techniques. The use of ICs let minicomputers become more and more powerful for their size. The desk-sized minicomputers of the 1960s became as powerful as a room-sized computer of the late 1950s. Now $10,000, drawer-sized minicomputers were as powerful as the older $100,000.
The late 1960s and early 1970, large-scale integration (LSI) become common. Large-scale integration was making it possible to produce more and more digital circuits in a single IC.
By the 1980s, very large-scale integration (VLSI) gave us ICs with over 100,000 transistors. By the mid 1970s, LSI had reduced the calculator to a single circuit. After the calculator was reducing, the next natural step was to reduce the architecture of the computer to a single IC. The microprocessor was the resulting circuit of achievement. The microprocessor made possible the manufacture of powerful calculators and many other products. Microprocessor could be programmed to carry out a single task> Products like microwave ovens, telephone dialers and automatic temperature-control systems become common place.
The early microprocessor processed digital data 4 bits (4 binary digits) at a time. These microprocessors were slow and did not compare to minicomputers. But new generations of microprocessors came fast. The 4 bit microprocessors grew into 8 bit microprocessors, then into 16 bit microprocessors, and then into 32 bit microprocessors. During the early 1980s, complete 8 bit microprocessor systems (microprocessors with memory and communications ability) were developed. These microcontrollers, or single-chip microprocessors, have become popular as the basis of controllers for keyboards, VCRs, TVs, microwave ovens, smart telephones, and a host of other industrial and consumer electronic devices.
The History of Technology
Posted by
Crystal
Stone Age- (beginning around 2 million years ago) Humans
were using tools made out of natural materials:
stone, wood, bone
were using tools made out of natural materials:
stone, wood, bone
Bronze Age- (3500 B.C.) Learned how to make bronze out of
copper and tin, this allowed us to make better
tools and weapons
copper and tin, this allowed us to make better
tools and weapons
A mixture of 2 or more metals is called an alloy
Iron Age- (1200 B.C.) Learned how to mine and use iron
which is harder than bronze and improved their
tools even more
which is harder than bronze and improved their
tools even more
Tigris Euphrates Valley- Early people developed flood
control
control
Egyptians- Discovered architectural forms that led to pyramids
and temple complexes
and temple complexes
Greeks and Romans- Developed the technology to build fast
ships and the arch
ships and the arch
China- Great wall was constructed for protection against invaders.
Also invented gun powder
Also invented gun powder
-Technologies people create change their lives. People began to farm land instead of just relying on hunting for food; this allowed them to have free time and a chance to stay in one place.
Closed Circuit Television (CCTV) Management and Operations
Tuesday, 10 April 2012Posted by
Crystal
AS/NZS 4360:2004: Risk Management describes how the objectives of analysis are to separate acceptable risks from major risks. Risk analysis involves the consideration of the sources of risk, their consequences and the likelihood that those consequences may occur.
Consequence
AS/NZS 31000:2009 Risk Management describes that it is important to recognise that the consequences of any particular risk event may impact in different ways at different levels. Financial costs, personal harm (physical and psychological), legal consequences and damage to reputation may all result from a single incident.
Table 1 shows the AS/NZS 31000:2009 Risk Management descriptors for consequence:
| Level | Descriptor | Description |
| 1 | Minimal | < $2000 (< $1000): Isolated brief coverage, single media outlet: Stakeholders experience minimal disadvantage (days): Process breakdown or inefficiencies that have a limited impact on the achievement of an objective: Minor injury requiring first aid only |
| 2 | Minor | $2,000 – $50,000 (< $10,000): Minor negative coverage, limited circulation for one day: Minority of stakeholders experience disadvantage (days - weeks): Process breakdown that impedes the achievement of one or more objectives or some inefficiencies in key processes: Minor injuries requiring medical attention |
| 3 | Moderate | $50,000 - $5,000,000 (< $50,000): Negative coverage lasting for several days, and/or frequent reoccurrence for several weeks: Multiple stakeholders experience significant disadvantage (weeks): Process breakdown that impedes the achievement of an important objective or causes extensive inefficiencies in key processes: Multiple casualties requiring hospital attention |
| 4 | Major | $5,000,000 - $100,000,000 (< $5,000,000): Negative significant coverage, appearing consistently over weeks Multiple stakeholders severely disadvantaged (weeks - months): Serious process breakdown that substantially impedes the achievement of a core objective: Multiple severe injuries, or a single fatality |
| 5 | Catastrophic | > $100,000,000 (> $5,000,000): Extreme negative coverage causing public outcry appearing consistently over weeks Majority of stakeholders severely disadvantaged (months): Serious process breakdown that prevents the achievement of mission critical objectives: Multiple severe injuries, including fatalities |
Likelihood
Table 2 shows the AS/NZS 31000:2009 Risk Management descriptors for likelihood:
| Level | Descriptor | Description |
| A (=5) | Almost Certain | Over 99% probability or ‘happens often’, or could occur within ‘days to weeks’ |
| B (=4) | Likely | >50% probability or ‘could easily happen’, or could occur within ‘weeks to months’ |
| C (=3) | Possible | >10% probability or ‘could happen, has occurred before’, or could occur within ‘a year or so’ |
| D (=2) | Unlikely | >1% probability or ‘has not happened yet, but could’, or could occur ‘after several years’ |
| E (=1) | Rare | <1% probability or ‘conceivable but only in extreme circumstances’: exceptionally unlikely, even in the long term future or a ‘100 year event’ or greater |
Qualifying the risk
Table 3 shows the AS/NZS 31000:2009 Risk Management qualitative risk analysis matrix for level of risk.
| Likelihood | Consequences | ||||
| Insignificant 1 | Minor 2 | Moderate 3 | Major 4 | Catastrophic 5 | |
| A - Almost Certain | High | High | High | Extreme | Extreme |
| B - Likely | Moderate | High | High | Extreme | Extreme |
| C - Possible | Low | Moderate | High | High | Extreme |
| D - Unlikely | Low | Low | Moderate | High | Extreme |
| E - Rare | Low | Low | Low | Moderate | High |
Legend
Extreme risk: immediate action required High risk: senior management attention needed
Moderate risk: management responsibility must be specified Low risk: managed by routine procedures.
1.1. CAMERA RISK ASSESSMENT - Camera Number(s) / Location(s)
| Key security risks | Comment on the risk or give an example to clarify the risk | Existing controls presently in place to mitigate against the risk | Adequacy of existing controls, use excellent =1 generally adequate =3 inadequate =5, none=7 | Likelihood use 5 = Almost Certain 4= Likely 3 = Possible 2 = Unlikely 1 = Rare | Consequence use 5 = Catastrophic 4 = Major 3 = Moderate 2 = Minor 1 = Minimal | Likelihood x Consequence | Risk rating | Treatments proposed, indicate treatment, person responsible, due date, review process |
| Burglary | | | | | | | | |
| Violence / Assaults | | | | | | | | |
| Stealing Offences | | | | | | | | |
This preliminary camera risk evaluation, as shown in Table 4 is formulated as a guide only. The identified risks should be ranked based on available information and opinion by the CITY NAME. A crime and CCTV risk workshop is recommended annually to accurately evaluate and rank risks in line with current crime prevention strategy and objectives. Crime risks should be rated in accordance with the Community Safety and Crime Prevention Plan priorities.
CAMERA RISK ASSESSMENT - Camera Number(s) / Location(s) (CONTINUED)
| Key security risks | Comment on the risk or give an example to clarify the risk | Existing controls presently in place to mitigate against the risk | Adequacy of existing controls, use excellent =1 generally adequate =3 inadequate =5, none=7 | Likelihood use 5 = Almost Certain 4= Likely 3 = Possible 2 = Unlikely 1 = Rare | Consequence use 5 = Catastrophic 4 = Major 3 = Moderate 2 = Minor 1 = Minimal | Likelihood x Consequence | Risk rating | Treatments proposed, indicate treatment, person responsible, due date, review process |
| Robbery (Stealing with Violence) | | | | | | | | |
| Anti-Social Behaviour | | | | | | | | |
| Vandalism/Criminal Damage | | | | | | | | |
| Sexual Offences | | | | | | | | |
CRIME RISK ASSESSMENT - Camera Number(s) / Location(s) (CONTINUED)
| Key security risks | Comment on the risk or give an example to clarify the risk | Existing controls presently in place to mitigate against the risk | Adequacy of existing controls, use excellent =1 generally adequate =3 inadequate =5, none=7 | Likelihood use 5 = Almost Certain 4= Likely 3 = Possible 2 = Unlikely 1 = Rare | Consequence use 5 = Catastrophic 4 = Major 3 = Moderate 2 = Minor 1 = Minimal | Likelihood x Consequence | Risk rating | Treatments proposed, indicate treatment, person responsible, due date, review process |
| Motor vehicle theft/break in/damage | | | | | | | | |
| Vehicle Driving Offences | | | | | | | | |
| Drug related offences | | | | | | | |
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