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In other views, organizational knowledge is not merely consider as individual one. Some of knowledge exist in group for [10]. Then the knowledge which is measured or measure something should cover 2 classification of knowledge i,e implicit and explicit and group, individual and organizational one.

The second dimension of this tetragonal basis of figure 1 is types of knowledge in an organization, individual and group from implicitly and explicitly.

Figure 2: equipoised cube for measurement method the necessities for

The cubical volume of figure 2 indicates integration of tetragonal base in measurement method with types of knowledge in organization

So we have a cube of 6 types of knowledge (from the intersection of implicit and explicit knowledge with indivisual, group, organizational knowledge) that each of then must be compared in the Tetragonal of "knowledge volume" , "knowledge volue" , "knowledge interest and expenses" and "Transformation speed of knowledge".

Now we should find a knowledge management model which is capable of integrating with this cognitive tetragonal model –Nonaka-

Jakichi Model is a suitable one to reconcile with this cognitive tetragonal model and can be considered as a basis for measurement model –Nonaka- Takochi Model as a cognitive model is based on types of knowledge. Hidden and obvious information have been discussed exactly in this model. In this model indivisual, group, organizational knowledge are converted to each other in a loop form too. [11] Then ,Nonaka. Takochi Model can be delineated as measurement Model base. But it should be mentioned here that this model has a dynamic nature.[12] in dynamic Models There are several main and important indexes that separate them from static ones.[13]

dependence to time; Dynamic models depend on time and in dingle of time they show different behavior from themselves which caused by main variable of time in them.

Cause and effect relationships: Dynamic Models are composed of varied cause and effect relationships. One cause itself can the effect of other cause. So in dynamic models the beginning strip of cause and effect relation ships is not clear but the cause and effect impacts of all indexes on each other is measurable and visible.

Feedback circles: in dynamic models feedback plays the main role. Any effect can effect on its cause. The increase of effect can boots or decrease cause directly or indirection.

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A heart attack is when low blood flow causes the heart to starve for oxygen. Heart muscle dies or becomes permanently damaged. Your doctor calls this a myocardial infarction

Causes

Most heart attacks are caused by a blood clot that blocks one of the coronary arteries. The coronary arteries bring blood and oxygen to the heart. If the blood flow is blocked, the heart starves for oxygen and heart cells die.

A clot most often forms in a coronary artery that has become narrow because of the build-up of a substance called plaque along the artery walls. (See: atherosclerosis) Sometimes, the plaque cracks and triggers a blood clot to form.

Occasionally, sudden overwhelming stress can trigger a heart attack.

It is difficult to estimate exactly how common heart attacks are because as many as 200,000 to 300,000 people in the United States die each year before medical help is sought. It is estimated that approximately 1 million patients visit the hospital each year with a heart attack. About 1 out of every 5 deaths are due to a heart attack.

Risk factors for heart attack and coronary artery disease include:

Bad genes (hereditary factors)

Being male

Diabetes

Getting older

High blood pressure

Smoking

Too much fat in your diet

Unhealthy cholesterol levels, especially high LDL ("bad") cholesterol and low HDL ("good") cholesterol

Higher-than-normal levels of homocysteine, C-reactive protein, and fibrinogen may also increase your risk for a heart attack. Homocysteine is an amino acid. C-reactive protein and fibrinogen are linked to inflammation. Fibrinogen is also involved in blood clotting

Angina is the primary symptom of coronary artery disease and, in severe cases, of a heart attack. It is typically experienced as chest pain and occurs when the heart muscle does not get as much blood (hence as much oxygen) as it needs for a given level of work (ischemia). Angina is usually referred to as one of two states:

Stable Angina (which is predictable)

Unstable Angina (which is less predictable and a sign of a more serious situation)

Click the icon to see an image about angina.

The intensity of the pain does not always relate to the severity of the medical problem. Some people may feel a crushing pain from mild ischemia, while others might experience only mild discomfort from severe ischemia.

Angina itself is not a disease. Much evidence indicates that onset of angina less than 48 hours before a heart attack may be protective, possibly by conditioning the heart to resist the damage resulting from the attack. Angina may be experienced in different ways and can be mild, moderate, or severe.

Stable Angina and Chest Pain

Stable Angina. Stable angina is predictable chest pain. Although less serious than unstable angina, it can be extremely painful or uncomfortable. It is usually relieved by rest and responds well to medical treatment (typically nitroglycerin). Any event that increases oxygen demand can cause an angina attack. Some typical triggers include:

Exercise

Cold weather

Emotional tension

Large meals

Angina attacks can occur at any time during the day, but most occur between 6 a.m. and noon.

Specific symptoms that are more likely to indicate angina include:

Angina pain or discomfort is typically described by patients as fullness or tingling, squeezing, pressure, heavy, suffocating, or griplike. It is rarely described as stabbing or burning. Changing one's position or breathing in and out does not affect the pain.

A typical angina attack lasts minutes. If it is more fleeting or lasts for hours, it is probably not angina.

Pain is usually in the chest under the breast bone. It often radiates to the neck, jaw, or left shoulder and arm. Less commonly, patients report symptoms that radiate to the right arm or back, or even to the upper abdomen.

Stable angina is usually relieved by rest or by taking nitroglycerine under the tongue.

Other symptoms that may indicate angina or accompany the pain or pressure in the chest include:

Shortness of breath

Nausea, vomiting, and cold sweats

A feeling of indigestion or heartburn

Unexplained fatigue after activity (more common in women)

Dizziness or lightheadedness

Palpitations

Unstable Angina and Symptoms of Possible Heart Attack

Unstable angina is a much more serious situation and is often an intermediate stage between stable angina and a heart attack, in which an artery leading to the heart (a coronary artery) becomes completely blocked. A patient is usually diagnosed with unstable angina under one or more of the following conditions:

Pain awakens a patient or occurs during rest.

A patient who has never experienced angina has severe or moderate pain during mild exertion (walking two level blocks or climbing one flight of stairs).

Stable angina has progressed in severity and frequency within a 2-month period, and medications are less effective in relieving its pain.

Fainting episode.

Unstable angina is now usually discussed as part of a condition called acute coronary syndrome (ACS). ACS also includes people with a condition called NSTEMI (non ST-segment elevation myocardial infarction) -- also referred to as non-Q wave heart attack. With NSTEMI, blood tests suggest a developing heart attack. These conditions are less severe than heart attacks but may develop into full-blown attacks without aggressive treatment. <!--[For more information, see In-Depth Report #12: Heart attack and acute coronary syndrome.]-->

Doctors use a number of factors to help predict which patients with unstable angina or acute coronary syndrome are most at risk for developing a heart attack.

First, patients are categorized by whether they have a history of heart disease or risk factors for heart disease (such as diabetes, high blood pressure, and peripheral artery disease) or other complicating conditions (such as lung disease and heart failure). The doctor also evaluates the severity of the angina. Other factors that pose a high risk for ACS include:

Age 65 years or older

Evidence of severe heart tissue injury

A history of severe chronic angina

Abnormal lung sounds called rales (a bubbling or crackling sound) on examination

ST-segment deviation on the electrocardiogram

Either very slow or very fast heat beats

Very low blood pressure

Heart Attack. A full-blown heart attack occurs with severe damage to the heart, which blocks oxygen.

People with known heart disease and any unusual chest pain or other symptoms described above that do not clear up with medications should call 911. The degree of pain and the specific symptoms before a heart attack vary greatly among individuals. Symptoms can be abrupt, gradual, or intermittent. Some studies suggest that nearly half of patients with heart attack do not have chest pain as the primary symptom. Patients most likely to have atypical symptoms are women and the very elderly (although they can certainly have classic heart attack symptoms as well).

Symptoms That Are Less Likely to Indicate Angina or a Heart Attack. The following symptoms are less likely to be due to coronary artery disease:

Sharp pain brought on by breathing in and or when coughing

Pain that is mainly or only in the middle or lower abdomen

Pain that can be pinpointed with the top of one finger

Pain that can be reproduced by moving or pressing on the chest wall or arms

Pain that is constant and lasts for hours (although no one should wait hours if they suspect they are having a heart attack)

Pain that is very brief and lasts for a few seconds

Pain that spreads to the legs

However, the presence of these symptoms does not always rule out a serious heart event.

Other Types of Angina

Prinzmetal's Angina. A third type of angina, called variant or Prinzmetal's angina, is caused by a spasm of a coronary artery. It almost always occurs when the patient is at rest. About two-thirds of people with it have severe atherosclerosis in at least one major blood vessel. Irregular heartbeats are common, but the pain is generally relieved immediately with standard treatment.

Silent Ischemia. Some people with severe coronary artery disease do not have angina pain. This condition is known as silent ischemia, which some experts attribute to the brain abnormally processing of heart pain. This is a dangerous condition because patients have no warning signs of heart disease. Some studies suggest that people with silent ischemia experience higher complication and mortality rates than those with angina pain.

Syndrome X. Syndrome X is a condition that occurs when patients have atypical angina chest pain. Their electrocardiograms are abnormal during a stress test, but they have no signs of blocked arteries. It is more likely to occur in women. Although it is unclear what causes this condition, imaging tests suggest that Syndrome X may also be caused by ischemia, as is angina.

Other Causes of Chest Pain or Discomfort

Chest pain is a very common symptom in the emergency room, but heart problems account for only 10 - 33% of all episodes.

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What is the effect of CNG on petrol engine?

I am looking for technical information on the following... Conversion of Diesel Engine to CNG... Type of kits that make it possible.... Technical information on how a Diesel engine can work on CNG, performance, cost etc Functioning of a CNG Conversion Kit.. CNG quality & performance issues, petrol vs CNG as fuel Effect of CNG on car engines.. Lower RPM's, Less power, engine load, lubrication and early wear out? Mixing ethanol in petrol... Change in chemical nature of petrol and its properties.. what ethanol achieves through mixing ... Good points/bad points, effect on the quality and energy output of petrol etc

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Ethanol is bad and creates many nasty acids that wear away the journal bearing babbits, etc. Many materials cannot stand up to the increase acidity present when burning higher percentages of ethanol. (Boy i hope i don't mean methanol instead of ethanol. You might want to double check me there!)CNG can ONLY be used on SUPERCHARGED diesel engines. To date, there are no SUPERCHARGED automotive diesel engines made. The only way to get CNG into a diesel engine is to use very large superchargers which run mechanically off the crankshaft to ensure enough air-fuel mixture gets into the engine. See Waukesha for stationary CNG products. Traditionally, many diesel/CNG power plants run on CNG most of the time to save $. CNG is GREAT for normally aspirated automotive spark-ignition engines. It may produce less peak power, but the cylinder wear is REDUCED, oil contamination REDUCED--the engine runs SO MUCH CLEANER it is unbelievable. Combustion chambers remain spotless and spark plugs stay clean. CNG evaporators need a heat source, so in cold climates you may have to have a preheater.You may be able to increase compression ratio when building up an automotive conversion--but don't overdo it. I know plenty of CNG trucks that end up blowing a head gasket because people have a lead foot. You could probably run a 9.0. The best engines to use are V-8 carbureted truck engines. Total fleets of frozen food delivery trucks have been converted to CNG--but none has a diesel engine--they are all gasoline type engines. So they do use them in trucks. CNG will run out fast in your automotive application. CNG must be stored in a gas phase, which means by the cubic foot. It is not practical usually to build CNG storage into a car, and check with your Dept. of Transportation on explosion hazards--it may be illegal in some cases to carry so much cubic feet of explosive gas on a car or in a non-rated tank. The heating value, i.e. energy per cubic foot of fuel is far less than gasoline, and less than propane. The most practical conversions for cars are propane kits. They are very simple: pressure regulator, evaporator, and some kind of throttle linkage. You will get a few more miles per bottle of propane than CNG. Both propane and CNG keep engines spotlessly clean. Be sure to start with a clean engine and be sure that the valves have valve seats in the heads. Exhaust gases can run the valves a bit hotter than when burning gasoline because of unburnt hydrocarbons in the exhaust--if your air-fuel ratio is right, you will never have that problem with CNG or LPG.