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Agilent EEsof EDA Virtual Network Analyser Software

Agilent EEsof Genesys virtual network analyzer software for creating S-parameter libraries, synthesizing narrow and broadband matching network in lumped

232Analyzer is an advanced serial port protocol analyzer software

232Analyzer is an advanced serial port protocol analyzer software, which allows programmers, engineers and others to control, monitor and analyze serial port (RS232 / RS485 / RS422 / TTL, etc.) activities.
232Analyzer allows you to control and monitor serial devices right from your PC. It supports data input and monitoring in Hexadecimal, Decimal, Octal, Binary and ASCII formats. It also allows you to change / monitor RS-232's line states: RTS, DTR, CTS, DSR, DCD, and RI. All data and signal flows are logged in the Communication Window, which can be saved as .txt, .doc or .rtf files for further analysis.
232Analyzer comes with many advanced features, such as:


- Being able to monitor communications between serial devices with timestamps;
- Programmable Buttons: Send up to 32 commands with a button click;
- Auto-Response: Automatically respond to incoming data / signals;
- Macros: Up to 64 steps of Logic and Timer processes for handling sophisticated serial devices;
- Checksum Calculator: Advanced checksum bytes calculator.


232Analyzer is useful for controlling, testing, developing, and debugging serial devices, control software and firmware. It is widely used in industrial and commercial control and automation systems (our customers include Siemens, Honeywell, Johnson Controls, Schneider Electric, Ericsson, etc.). The FREE Limited Version has no time limitation, so feel free to use or distribute it.

How to choose Analyzer??

Choosing a protocol analyzer is not something that you should jump right into. There are several good candidates out there. The three most popular ones that I know of are Sniffer from Sniffer Technologies aka Network Associates), Etherpeek and Ethereal I used to recommend a fourth candidate from Novell but they seem to have stopped supporting their software based analyzer. I haven't seen any new protocol decodes released for several years.

The cost of these ranges from free (in the case of Ethereal) to more than $10,000 for a fully equipped Sniffer package from Network Associates. I encourage you to get an eval copy of the above mentioned sniffers and run them through their paces. Etherpeek and Ethereal can be downloaded while Sniffer will require you to fill out a form and someone will call you in a couple of days to follow up.

You won't have to delve deep into the guts of a packet or need to decode the parts that make up a packet frame to see a problem. When I have used a protocol analyzer in the past, I have found problems by finding abnormal traffic on the network. Just like your anti-virus software, you should also keep the protocol decodes up to date. This will allow you to see the traffic that is on the wire.

Most of the vendors will offer some type of training to help you use their product to its fullest. One last option comes from Laura Chappell. Laura travels the world giving seminars on how to use protocol analyzers and has written several books on the subject. for packet trace files she has made available for download and for books she has written on the subject. If you have the chance, go hear her speak either at Novell's Brainshare conference or at other events. This is money well spent!

A Packet Sniffer?? Whats That??

A packet sniffer (also known as a network sniffer, network analyzer or protocol analyzer or, for particular types of networks, an Ethernet sniffer or wireless sniffer) is computer software or computer hardware that can intercept and log traffic passing over a digital network or part of a network.[1] As data streams flow across the network, the sniffer captures each packet and eventually decodes and analyzes its content according to the appropriate RFC or other specifications.


On wired broadcast LANs, depending on the network structure (hub or switch), one can capture traffic on all or just parts of the traffic from a single machine within the network; however, there are some methods to avoid traffic narrowing by switches to gain access to traffic from other systems on the network (e.g. ARP spoofing). For network monitoring purposes it may also be desirable to monitor all data packets in a LAN by using a network switch with a so-called monitoring port, whose purpose is to mirror all packets passing through all ports of the switch. When systems (computers) are connected to a switch port rather than a hub the analyzer will be unable to read the data due to the intrinsic nature of switched networks. In this case a shadow port must be created in order for the sniffer to capture the data.

On wireless LANs, one can capture traffic on a particular channel.

On wired broadcast and wireless LANs, in order to capture traffic other than unicast traffic sent to the machine running the sniffer software, multicast traffic sent to a multicast group to which that machine is listening, and broadcast traffic, the network adapter being used to capture the traffic must be put into promiscuous mode; some sniffers support this, others don't. On wireless LANs, even if the adapter is in promiscuous mode, packets not for the service set for which the adapter is configured will usually be ignored; in order to see those packets, the adapter must be put into monitor mode.


[edit] Uses
The versatility of packet sniffers means they can be used to:

Analyze network problems.
Detect network intrusion attempts.
Gain information for effecting a network intrusion.
Monitor network usage.
Gather and report network statistics.
Filter suspect content from network traffic.
Spy on other network users and collect sensitive information such as passwords (depending on any content encryption methods which may be in use)
Reverse engineer protocols used over the network.
Debug client/server communications.
Debug network protocol implementations.

[edit] Example uses
A packet sniffer for a token ring network could detect that the token has been lost or the presence of too many tokens (verifying the protocol).
A packet sniffer could detect that messages are being sent to a network adapter; if the network adapter did not report receiving the messages then this would localize the failure to the adapter.
A packet sniffer could detect excessive messages being sent by a port, detecting an error in the implementation.
A packet sniffer could collect statistics on the amount of traffic (number of messages) from a process detecting the need for more bandwidth or a better method.
A packet sniffer could be used to extract messages and reassemble into a complete form the traffic from a process, allowing it to be reverse engineered.
A packet sniffer could be used to diagnose operating system connectivity issues like web,ftp,sql,active directory,etc.
A packet sniffer could be used to analyse data sent to and from secure systems in order to understand and circumvent security measures, for the purposes of penetration testing or illegal activities.
A packet sniffer can passively capture data going between a web visitor and the web servers, decode it at the HTTP and HTML level and create web log files as a substitute for server logs and page tagging for web analytics.

Blood Gas Analysis and Critical Care Medicine

Blood Gas Analysis and Critical Care Medicine
JOHN W. SEVERINGHAUS, POUL ASTRUP, and JOHN F. MURRAY

Departments of Anesthesiology and Medicine, and the Cardiovascular Research Institute, University of California San Francisco, and the San Francisco General Hospital Medical Center, San Francisco, California; and Department of Clinical Chemistry, Rigshospitalet, Copenhagen, Denmark

Critical care medicine is one of the newest and most rapidly growing medical specialties. Surprisingly new, in fact, because critical care medicine is, basically, applying physiologic principles to the care of seriously ill patients, something physicians have been trying to do for centuries. Modern critical care medicine is distinguished from its predecessors by incredible products of technology, advances in biochemistry, and astonishing know-how. We now have at our disposal sophisticated monitoring devices that provide moment to moment information about key circulatory and respiratory physiologic variables, how they are deranged by disease, and how they respond to intervention. We also have available an astonishing variety of high-tech instruments and powerful medications that we use to remedy ailing physiology, ventilators for breathing, machines to rid the body of excess fluid and impurities, vasopressor drugs to shore up flagging blood pressure, and even instruments to supplement a failing heart. Another distinguishing feature of critical care medicine is that it is practiced in specialized facilities, intensive care units, within acute care hospitals; these focal points for costly instrumentation are also headquarters for the expertly trained and knowledgeable physicians, nurses, and other professionals who care for desperately ill patients.

This paper retraces the history of the development of knowledge about blood gas transport, including the discovery of oxygen and carbon dioxide, the evolution of techniques to measure respiratory gases in the blood, and finally, how all this came together in Blegdamshospital, Copenhagen, on August 25, 1952, when an ingenious anesthetist, Bjorn Ibsen, came out of the operating room and started the modern critical care movement. We conclude with some comments about the remarkable changes that have occurred during the 45 years between then and now, and we make a few speculations about what the future might have in store.

BLOOD GAS TRANSPORT

According to Hippocrates (460-377 BC), good health resided in a proper balance among the four humors: blood, phlegm, black bile, and yellow bile, a balance that depended on the generation of life-giving heat within the left ventricle. Aristotle (384-323 BC) concluded that arteries carried air, but Erasistratus of Cos (about 330-250 BC) taught that "pneuma," created within the left ventricle from lung air, was the substance pumped through arteries to the tissues. Galen (130-199 AD) believed that the heart sucked blood-cooling air from the lungs into the left ventricle where the vital heat was generated, that pneuma was transported in arteries to the tissues, hence to veins via anastomoses, and that after arriving back in the heart, blood passed through minute pores in the septum from the right into the left ventricle for replenishment. These ideas went unchallenged by physicians until the 16th century.

Michael Servetus (1511-53) studied and practiced medicine, but his principal interest became theology (1). In Christianismi Restitutio (1553), Servetus contradicted Galen, concluding that the communication between the right and left sides of the heart was "not through the middle wall of the heart . . . but by a very ingenious arrangement the subtle blood is urged forward by a long course through the lungs," the first postulate of the existence of pulmonary capillaries. Severtus sent his book to John Calvin, who considered it heresy, had him arrested, jailed, and burned at the stake within the year of publication.

It remained for William Harvey (1578-1657), a brilliant anatomist and physician, to describe the circuit of blood flow around the body, including its circulation through the lungs. In his monumental De Motu Cordis (1628), Harvey flatly stated that blood was pumped from the right ventricle through the pulmonary circulation to the left ventricle, passing through "the invisible porosities of the lungs and the minute connections of the lung vessels." These theoretic pulmonary porosities became anatomic reality when first seen by the celebrated Italian microscopist Marcello Malpigi (1628-94) (2). Thus, the anatomy of the circulation was concisely described, but the nature of the vital ingredient by which breathing fed the inner life-giving flame remained elusive. It took over 100 years to find it.

Discovery of Carbon Dioxide

Joseph Black (1728-99), who became Professor of Chemistry in Edinburgh, showed while he was a medical student that large quantities of a gas, which he called "fixed air" (carbon dioxide), were generated by heating or acidifying chalk. He was the first to prove that the same gas was present in exhaled air (3).

Discovery of Oxygen

Robert Boyle (1627-91) established the fact that the long-sought, life-sustaining substance was contained within air itself (4). His assistant, Robert Hooke (1635-1703), demonstrated in 1667 that a dog whose exposed lungs had multiple pleural punctures could be kept alive by providing a constant flow of air through the trachea without any movement of the lungs. Hooke showed, as had Richard Lower (1631-91), that arterialization of blood in the lungs occurred through the introduction of fresh air. No one noted that something was taken out of the air and something else was added.

The English Unitarian "dissenting" minister and amateur chemist, Joseph Priestley (1733-1804), who lived next door to a brewery, got interested in the waste gas product of fermentation and started investigating gases. He discovered that the gas given off by heating mercuric oxide caused a much brighter flame than plain air. In 1774, he showed that this gas was essential not only to combustion, but also to respiration and to the greening of plants. Priestley was the first to demonstrate that ordinary air, in which a candle would no longer burn and a mouse no longer live, might regain its former vital properties if green plants were kept within the sealed chamber. He eventually managed to isolate 10 new gases, including nitrous oxide and carbon monoxide, invented carbonated beverages, gum rubber erasers, and refrigeration. In 1791 his Birmingham home was burned and his laboratory trashed by a royalist-sectarian mob incensed by his support of the French revolution. He emigrated with his family to Pennsylvania in 1794. Priestley was one of the great social and political minds of the Enlightenment. He had a significant influence on his good friend Thomas Jefferson, and had his portrait painted (Figure 1) by the most famous American painter of the time, Gilbert Stuart.

FOR OUR ENVIRONMENT AND OUR CUSTOMERS' MONEY

FOR OUR ENVIRONMENT AND OUR CUSTOMERS' MONEY
COMBUSTION ANALYSIS
The environment has to deal with ever larger concentrations of pollutants due to the use of all types of combustion processes. Smog formation, acid rain and the constantly increasing number of allergies are a direct result of this development. The path to environmentally friendly energy production must therefore lead to a reduction in the emission of pollutants, which is only possible when the existing equipment is working correctly and defective equipment is taken off line. Flue gas analysis and a flue gas analyser enable you to measure the concentrations of the pollutants present and to adjust your burners for optimal combustion.

This branch can be seen as connected to several very different industries. It has a function as environmental control, as simple air pollution control equipment for its own sake. It can be seen as a supplement to general maintenance services and hence the protection of an investment, and it is also a valuable tool for reducing fuel costs. Known under many names, flue gas analysis, stack emissions monitoring or simply gas analysis. Should it become part of military procedure, we will probably be hearing about gas monitoring, stack as well! If we talk of compliance testing, then the legal aspect of the matter becomes clear, as well as the interest of the EPA in the matter. Without a flue gas analyser, there is no real way of checking your own level of compliance and hence avoiding nasty surprises when official testing with a flue gas analyser is carried out.

Many new sections keep being created. The modern interest in biogas has been increased by the high cost of fuel in recent times and the greenhouse effects caused by simply venting these gases to atmosphere. NO2 has become more of a topic, now that carbon monoxide has generally been reduced. Basically, stack testing is a growing business and will be with us for as long as we burn fossil fuels. Most of this site will employ the British expression, flue gas analyser and not the American flue gas analyzer, although there are some mixtures to be found. The two terms are, of course, identical in meaning. There are many other synonyms in common usage, and these will be mixed freely in some places. I apologise in advance for what may be seen as inconsistency. It is more a planned attempt to make everybody feel at home!