Spooling:-
Due to I/O limited jobs the C.P.U remain idle for most of the time, which effects the efficiency of the whole system. So to increase the speed of C.P.U the IBM used first time the magnetic tape and spooling system in early 1960. Spooling in the abbreviation of (Simulation Peripherals Operations Of Line). On line mean to keep all the peripherals busy at the same time. Spool can be define as a temporary storage use to remain the speed difference among the difference devices.
There arte two types of spooling.
1. off line spooling
2. online spooling
1. Off line spooling:-
In this type of spooling, the user is not interact with then jobs, when they are processed all the jobs and then associated data is stored on a fast speed device like magnetic tape using slow and expensive processor when hatch of job is formed , it is transferred to the main CPU for processing . The job and their related data is processed and the results one once again stored on the magnetic tape when output is required, the stored output data is transferred to output device.
2.Online spooling:-
There are different disadvantages of off line spooling e.g. It takes more time in reading, processing and printing. This job cannot be given a priority etc.
To overcome these problems online spooling technique is used.
In this system there is only a single processor and the spooling system existing that processor. The data is to be processed is transferred between slow device, the card reader and printer and backing storage considers a system.
Data is read from input device character by character and stored in input buffer, when buffer is filled data is transferred to backing storage, thus block of data is transferred to CPU and after processing, it is send to back store which is again transferred to the output buffer and then transferred to output device.
On line spoolings increase the efficiency of both I/O devices and CPU.
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Buffering in computer
Buffering:-
Buffer is a special kind of memory location, where data is stored temporary. Buffer is used with put devices and also with output devices.
An input buffer holds the data received from an input device before going for processing, while an output buffer holds the data received from the main memory before it is send to the output device.
Buffer is used to compensate the difference between high speed processor and low speed I/O devices.
Why Buffer is used:-
To read data directory from input devices decrease the efficiency of C.P.U.
Similarly when processor sends data to output device directly, it is a chance of loss of data because of its low speed. Therefore memory areas are needed which hold the data before processed. These memory locations are called buffers.
By using buffers C.P.U was used efficiently as well as I/O device were kept busy all the time. The time was also saved up to a limit because when C.P.U is processing at the same time I/O devices are busy for reading and writing. Buffering technique is used to operate slower devices with faster C.P.U.
Buffering Techniques:-
The techniques that are used to increase the efficiency of a processor are called as buffering techniques. Following buffering techniques are used.
Type of buffer:-
1. Single buffering.
2. Double buffering.
3. Cyclic buffering.
1. Single Buffering:-
In the techniques only one buffer is used between input and C.P.U and C.P.U to output. The buffer accepts the data from an input device character by character and when the buffers were filled then it is transferred to the C.P.U. The C.P.U accepts the data as a whole and processes it, in the mean time the empty buffer again filled character by character. The processed data is transferred to output buffer and from this buffer it is again transferred to the output device.
2. Double Buffering:-
In this technique two or more then two buffers are used.
The data is transferred from input device to the first buffer when it is filled then it is moved to C.P.U and at the same time 2nd buffer is start filling and when is filled and transferred to C.P.U the first buffer is ready for again getting data. It increases the efficiency of C.P.U.
3. Cyclic buffering:-
In double buffering technique memory space is wasted, therefore another buffering technique called cyclic buffering is used. In this technique a long single buffer is establish in which data is input by buffer pointer and outputted through user pointer. The buffer pointer writes the inputted data character by character in the buffer and the user pointer remove the data from it. A character is placed at the end of line. If the data printed is faster then the processing then the buffer pointer might over take the processing pointer and over writing may take place. In case of over writing the previous data is missed but if processing pointer or user pointer is faster then the inputting data then the processing pointer may over take the buffer pointer. This problem can be solved by using halt line pointer.
Halt line pointer indicate that last character stored in buffer which is not read for processing.
Posted by: Wasim Javed
Buffer is a special kind of memory location, where data is stored temporary. Buffer is used with put devices and also with output devices.
An input buffer holds the data received from an input device before going for processing, while an output buffer holds the data received from the main memory before it is send to the output device.
Buffer is used to compensate the difference between high speed processor and low speed I/O devices.
Why Buffer is used:-
To read data directory from input devices decrease the efficiency of C.P.U.
Similarly when processor sends data to output device directly, it is a chance of loss of data because of its low speed. Therefore memory areas are needed which hold the data before processed. These memory locations are called buffers.
By using buffers C.P.U was used efficiently as well as I/O device were kept busy all the time. The time was also saved up to a limit because when C.P.U is processing at the same time I/O devices are busy for reading and writing. Buffering technique is used to operate slower devices with faster C.P.U.
Buffering Techniques:-
The techniques that are used to increase the efficiency of a processor are called as buffering techniques. Following buffering techniques are used.
Type of buffer:-
1. Single buffering.
2. Double buffering.
3. Cyclic buffering.
1. Single Buffering:-
In the techniques only one buffer is used between input and C.P.U and C.P.U to output. The buffer accepts the data from an input device character by character and when the buffers were filled then it is transferred to the C.P.U. The C.P.U accepts the data as a whole and processes it, in the mean time the empty buffer again filled character by character. The processed data is transferred to output buffer and from this buffer it is again transferred to the output device.
2. Double Buffering:-
In this technique two or more then two buffers are used.
The data is transferred from input device to the first buffer when it is filled then it is moved to C.P.U and at the same time 2nd buffer is start filling and when is filled and transferred to C.P.U the first buffer is ready for again getting data. It increases the efficiency of C.P.U.
3. Cyclic buffering:-
In double buffering technique memory space is wasted, therefore another buffering technique called cyclic buffering is used. In this technique a long single buffer is establish in which data is input by buffer pointer and outputted through user pointer. The buffer pointer writes the inputted data character by character in the buffer and the user pointer remove the data from it. A character is placed at the end of line. If the data printed is faster then the processing then the buffer pointer might over take the processing pointer and over writing may take place. In case of over writing the previous data is missed but if processing pointer or user pointer is faster then the inputting data then the processing pointer may over take the buffer pointer. This problem can be solved by using halt line pointer.
Halt line pointer indicate that last character stored in buffer which is not read for processing.
Posted by: Wasim Javed
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Buffering
Functions of Blood
1. Transport of respiratory Gases:
After inhaling oxygen, it reaches the lungs where it combines with hemoglobin and result in the formation oxy-hemoglobin
This oxy-hemoglobin is carried by the blood to the tissues where it breaks into Hb and O2.
The CO2 is carried by the blood to the lungs from where it passes out.
2. Transport of iron:
Inorganic iron is attached with a special type of protein which transports the iron in the body to various places.
3. Transport of nutrition:
It carries digested food material, absorbed from intestine to the tissue cells for utilization. It also carries nutritive material from storage depots to the tissues cells.
Posted by: Wasim Javed
After inhaling oxygen, it reaches the lungs where it combines with hemoglobin and result in the formation oxy-hemoglobin
This oxy-hemoglobin is carried by the blood to the tissues where it breaks into Hb and O2.
The CO2 is carried by the blood to the lungs from where it passes out.
2. Transport of iron:
Inorganic iron is attached with a special type of protein which transports the iron in the body to various places.
3. Transport of nutrition:
It carries digested food material, absorbed from intestine to the tissue cells for utilization. It also carries nutritive material from storage depots to the tissues cells.
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Functions of Blood
Plasma
It is the liquid portion of the blood which is about 55% of the volume of the blood. It is mainly water which is about 90% by weight of the plasma. A large no of organic and inorganic substances are dissolved in water. Plasma is composed of organic and inorganic constituents.
(a) Inorganic constituents:
0.9% of the plasma is made up of Na, Ca ions. Which are move abundant while K, mg P and Cu ions are in lesser amounts? The cheap salt in the plasma is the Nacl.
(b) Organic Constituents:
I. 7.5% of plasma is made up of different kinds of blood portions such as serum, albumin, serum globulin, fibrinogen and prothrombin.
II. Simple :
They constitute about 0.1% in this case glucose is move abundant.
III. Product of digestion & Metabolic Wastes:
2—3% of plasma is made up of products of digestion like amino acids, fatty acids etc and metabolic wastes such as Urea, Uric acid and CO2 etc.
IV. Fats:
Neutral fats, phospholipids, cholesterol and etc.
V. Antibodies:
These are the blood proteins which provide immunity against certain diseases.
VI. Hormones:
Some blood protein is hormones interval secretion, enzymes (lipase, amylase, phosphates
VII. Coloring matter:
The yellow color of the plasma is due to small amounts of biluribin, carotene and xanthophyllin.
Posted by: Wasim Javed
(a) Inorganic constituents:
0.9% of the plasma is made up of Na, Ca ions. Which are move abundant while K, mg P and Cu ions are in lesser amounts? The cheap salt in the plasma is the Nacl.
(b) Organic Constituents:
I. 7.5% of plasma is made up of different kinds of blood portions such as serum, albumin, serum globulin, fibrinogen and prothrombin.
II. Simple :
They constitute about 0.1% in this case glucose is move abundant.
III. Product of digestion & Metabolic Wastes:
2—3% of plasma is made up of products of digestion like amino acids, fatty acids etc and metabolic wastes such as Urea, Uric acid and CO2 etc.
IV. Fats:
Neutral fats, phospholipids, cholesterol and etc.
V. Antibodies:
These are the blood proteins which provide immunity against certain diseases.
VI. Hormones:
Some blood protein is hormones interval secretion, enzymes (lipase, amylase, phosphates
VII. Coloring matter:
The yellow color of the plasma is due to small amounts of biluribin, carotene and xanthophyllin.
Posted by: Wasim Javed
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Plasma
Blood Pressure
Blood pressure is the force of blood against the wall of the blood vessels. It differs in various parts of the circulatory system. For example the blood pressure is normally 140 mm mercury in case where the blood leaving. The ventricles and entering the aorta under high pressure, the highest arterial blood pressure is found during the contraction of the heart ventricles. This is called systolic pressure. The lowest blood pressure is found during the relaxation of ventricles and it is called diastolic pressure, usually in the range of 70---85.
Posted by: Wasim Javed
Posted by: Wasim Javed
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Blood Pressure
Blood of our body
Blood is the circulatory fluid present within the blood vessels. It is highly complex substance composed of a large variety of dissolved and suspended materials.
Volume:
In adult male the volume of the blood is 5 liters but in case of female it is about 4.6 or 4.8.
PH of blood:
The PH of the blood is 7.4----7.6.
Rate of flow of blood:
The rate of flow differs in various blood vessels. In aorta it is high nearly 400----500 mm/second. It greatly reduced in the capillary which is about 1 mm/second and increase in large vein and is about 150 mm/second.
Specific Gravity:
Specific gravity of blood is 1.055-----1.060. Specific gravity rapidly fall after the birth due to destruction of R.B c’s and is increased when H2 O is lost from the body e.g diarrhea.
Composition of Blood:
If blood is put in a test tube along with some anticoagulant, it quickly separates into two layers, the upper yellowish and Semi-transparent layer is the plasma and the lower layer contains the blood cells i.e 1.R.B.c 2.W.B.c 3.Platelets
Posted by: Wasim Javed
Volume:
In adult male the volume of the blood is 5 liters but in case of female it is about 4.6 or 4.8.
PH of blood:
The PH of the blood is 7.4----7.6.
Rate of flow of blood:
The rate of flow differs in various blood vessels. In aorta it is high nearly 400----500 mm/second. It greatly reduced in the capillary which is about 1 mm/second and increase in large vein and is about 150 mm/second.
Specific Gravity:
Specific gravity of blood is 1.055-----1.060. Specific gravity rapidly fall after the birth due to destruction of R.B c’s and is increased when H2 O is lost from the body e.g diarrhea.
Composition of Blood:
If blood is put in a test tube along with some anticoagulant, it quickly separates into two layers, the upper yellowish and Semi-transparent layer is the plasma and the lower layer contains the blood cells i.e 1.R.B.c 2.W.B.c 3.Platelets
Posted by: Wasim Javed
Labels:
blood
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