【 Weak current College 】 100 decoration tips (2)

Third, woodworking
53, to the best drying larch keel
54, large wood bought dried after going to sawing
55, woodworking approach to playing the House horizontal lines
56, color Panel came in to buy the paint brush, prevent dirty
57, ceiling fans can't install in ceiling keel
58, color Panel construction to advance pick color
59, suspended ceiling of hanging bar distance wall shall not be greater than 300
60, gypsum board with countersunk head self tapping screws, into the plate surface 1 ~ 2MM and anti-rust treatment, not gun nail
61, gypsum board, the distance between the nails must be no greater than 200
62, gypsum board walls to and 3 joints for crack treatment
63, gypsum board Yang Kok Department preferably done Yang Kok bar protection
64, wooden doors down from emerging Office to paint
65, the bottom of the toilet door set to brush waterproofing
66, door size should be consistent
67, try not to let the wood furniture, do not do good
68, cabinets to buy whole, wood do not design is out
69, the dimensions must be considered good, looks more trouble
70, own movable door do dark orbit, then no way maintenance
71, bathroom small try sliding door, do not open the door, the local
72, unsure of carpentry must communicate with the foreman, never let them up front
73, money in your hand is the clincher
74, with the baby, glass to use less
75, be sure to let workers look drawings
76, kitchen drawer is useful
77, floor joists smoothness is 5MM
78, wool paved floor to 30 ° or 45 °, plates and plate between 2 ~ 3MM, sewn to stagger the
79, floors and walls to leave between 8 ~ 10 mm joints
80, composite floor length exceeds 8M to consider expansion joint
81, use density Board do door set
82, hinges and hardware must use good
83, Yuba to mounted on wood joist, cannot be directly mounted on the ceiling
Fourth, painter
84, dark LaTeX construction try not with water, or prone to chromatic aberration
85, gypsum board joints to bandage
86, walls have gaps to really cool cloth on better
87, original wall some PuTTY preferably eliminate, or brush again glue seal-solid
88, try to buy a brand of paint, decoration companies recommend or foreman recommended no famous try not to use
89, weather, not too wet, paint brushes
90, paint, coating and grinding to completely dry out after
91, next paint construction will have to wait for the first line after the paint dry
92, metal surface oil paint to do anti-rust treatment
93, the weather is too cold, painted the construction quality is poor
94, doors, paint, use masking cleaved hinge and lock
95, it was so hot, it is necessary to pay attention to ventilation
96, wallpaper, the wall brush boiled oils
97, Schimmel, switch, socket panels removed
98, light, light of latex paint to a complete complement of prone to chromatic aberration
99, tijuexian installed PuTTY and latex paint to fill the gap
100, frosted glass to protect the good with newspaper

【School】 talk about remote meter weak current technical status and development trend of China --- Power By weak home 【Network】..

<br> [Abstract]: Remote meter reading system that is in focus, but also difficult to analyze its current situation, predict its future development of the industry for the promotion of meter reading is important.. <BR> [Key words .]: remote water meter, meter reading <BR> <BR> 2001, the author has published an article "China's emergence and development of remote meter" (after the magazine article to be six., eight sites reproduced).. .In this paper, twelve years after the author has in the national patent office to register the background of six patented inventions, discussed China's emergence and development of remote meter course.. On the remote meter which was passed from the built-in external sensor, .photoelectric sensor from the switch to self-sensing methods to maintain a description and analysis are done.. When three years, analysis of past research that we have a role?. The original authors believe that the most advanced remote from the meter to keep switching .it still advanced?. On the future of the remote meter is accurate forecast made?. This will make elaborate.. <BR> <BR> One. Pulse current situation and development of remote meter <BR> First of all, .including two pulse sensing method has been largely eliminated from the meter reading area, and they are the optical sensing methods and Huo. Seoul sensing methods.. <BR> Tends to eliminate the reason is because: 1. With the reed, and other .contact sensing methods, with high power consumption of the shortcomings of their own, which makes some of the needs of micro-power operation of the occasion can not be used.. 2. Fibrillation threshold in error can not overcome the shortcomings of the signal. ..3. External power supply is for the inconvenience and trouble.. <BR> Course, the Hall sensor way through a decade of updated sound, if not better than the way it appears, it may also be retained.. However, compared .with the self-holding switch, Hall sensing methods in reliability, accuracy, micro-power, low cost, etc. are not dominant, which makes the Hall sensor means losing the last space.. <BR> Contrast, the optical sensing methods ., not to mention clumsy and defects, and past year and more still in use almost hear the sound.. <BR> Single reed switch sensor means the already "notorious", the disadvantages can not solve the contact bounce less insensitive multi- .counting and counting sensor problem.. Applied to the scene a few years ago nearly all of these products are abandoned or replace them.. However, some people do not know the business and the pursuit of accuracy is not the case, there are still people .in use.. <BR> Compared with the double-reed pipe alone reed switch with a significant improvement, the author of "China's emergence and development of remote water meter," an article that made their own invention (patent number of .a high precision meter.: 99206865.7) structural principle is described in detail.. In actual use, the double reed sensor there are still some problems.. 1. The reed sensor sensitivity limitations, there will be discarded weak magnetic data, magnetic induction intensity .of the same problems.. 2. Collector detected on two switches, which need to add an interface like any other remote tables as if on the short circuit, open circuit, also were detected, then it will be more complicated.. 3. For .the external magnetic field, which is neither easy to external magnetic shield, not a self-function.. <BR> "China's emergence and development of remote water meter," a text, with the larger space of the self-holding .switch demonstrated the superiority of remote water meters.. The first time in three years, although the remote method is technically still retains its original features, but in the production process has done a lot of improvement and amendment.. Type of product specifications to the .hundreds of species of mold manufacturing reached a hundred of the actual use has spread from the original thirty thousand to five hundred thousand or more, and to promote faster expansion.. Far from the meter to keep switching from one technology project is completely transition to a .mature product, but also rose to a certain well-known brands of merchandise.. Its accurate, reliable, low cost, easy to use as the leading edge of the meter reading market.. This process is thought of the idea three years ago exactly ... <BR> To keep switching from the remote meter remote water meter will be the mainstream product.. <BR> <BR> II. Direct-reading current situation and development of remote meter reading remote meter straight <BR> .; divided into four types: photoelectric, contact type, camera type, count type.. They have two common advantages: 1. Table with the data is read out on the data displayed on the dial, not the pulse.. 2. Usually do .not need electricity, just read the moment in power, therefore, not afraid of power outages.. In theory, it is always read data and dial data synchronization.. Therefore, direct-reading before the year 2000 the concept of remote meter generation, .by 2002 the scene after the application of the actual product, has been tracking people's pets and attention.. By 2003, the national standards setting process is also specifically incorporated into the direct-reading the concept of remote table; the direct reading remote table appears ., "Remote pulse vitality of the table whether there are" big on more. its attention to a climax.. <BR> Remote meter direct-reading photoelectric type as the first, its structure by: a water wheel in each week to .set up five reflector surface, the location of the corresponding set five Optocoupler. device.. Coupler is reflected by total number of rounds to determine the location.. Want to read a few words to the installation of wheel sensors.. For example: Read .5 digits on the installation of 5 × 5 = 25 of the sensing device.. This direct-reading water meters in the table because all devices are within the wheel around the core, therefore, generally use the dry water meter.. <BR> .; Remote meter reading directly contact the structure by: dial in the meter pointer, a pointer to each of the following axis potentiometer fitted with a synchronous, measured by the contact resistance of the potentiometer to determine the pointer. position.. This direct-reading .water meter water meter can be used wet.. <BR> Camera remote meter direct-reading method is relatively simple structure, the mechanical wheel display window to install a camera to shoot digital images can be heard.. <BR> Remote direct .-reading meter count is collected each pulse of the chip installed in the water, through the battery to maintain its work, the records and the accumulated data is stored in the chip, the data read from the chip is synchronous data dial ... < .; BR> In addition, there are direct-reading remote meter reading and other types of bar code directly, not discussed here.. <BR> Although the direct remote meter reading has outstanding advantages, but they popularized the practical effect is not satisfactory ... Comprehensive analysis of the problems, about the following: optical, two ways to contact terms of structure too complicated.. 1. The value of existing civilian water conditions, to create such a high precision products, the cost to an acceptable level and .the market itself is a contradiction.. 2. They have changed the standard meter of the original structure, the accumulation of human beings for decades to create a "standard, reliable, sophisticated, mature," the perfect product to be destroyed. .. Can the short term to establish a new, mature structure and standards, is questionable.. 3. So complex products in large quantities and can stand the test of long life, yet to be discussed, has been exposed many problems.. < .BR> Camera direct-reading water meter water meter does not change the original mechanical standards, the structure is relatively simple, but the image processing is too complex, the image of the fuzzy numbers into digital is also difficult.. Many of the current bus .system, sub-wire meter reading systems are not common.. <BR> Produced in more than an idea in three ways, namely: additive instead of a mechanical electronic accumulate.. Why?. Why should we care easy to ask difficult, .the development of electronic technology to this day, do not even have a "cumulative" are not complete it?. <BR> Following direct-reading counter arguments about remote meter.. Remote meter existing switching module plus a micro chip and button .batteries.. Accumulation can be made to store data, but also remote meter communication to send information.. Its output is only two lines, as long as a connection to the bus to complete the full installation, meter reading at any time transfer station will .be able to read meter data.. Its function and role of direct-reading table with the first three are the same, each meter can work independently from the bus, even if the external stop electricity, water down the line, water moved a bit ., do not affect the meter count.. With the success of its current three mature technology.. 1. Self-holding switch is admissible.. 2. Lithium accumulation of memory chips support.. 3. Standard communication protocol of the bus transfer. .. Because these technologies are experiencing a few years, decades of proven technology, and in the production process, raw material supply and service system, and so fit with the conventional products.. Therefore, its success "winner.". < .BR> Remote direct-reading meter count will be the direct remote meter-reading the mainstream products.. <BR> <BR> Third, there is no mature products business success no <BR> remote meter reading is a very difficult .high-tech systems engineering, not business property, and certainly not "pass reselling.". On the rare technology breakthroughs against those who have been advertising a big fuss on the "speculation.". Industry in the meter reading, .eating too much this loss of business, a typical IC card water meter is the promotion process.. IC card water meter unit of ten years ago with research and development, R & D unit in 2000 has reached hundreds, advertising Chaozuo also follow.. .2002 is a strange phenomenon occurred: those strong, skilled, experienced voice of the old R & D units smaller and smaller.. Those who are just joining the business, no experience of the "greenhorn" (not tasted that bad) are still .in there yelling, it seems the market today won.. <BR> This, the authors propose the following for reference: <BR> 1. Do not blindly pursue passive remote water meter, remote meter active denial.. Active remote meter .the problems has been the new micro-power technology and battery technology solution, has entered the mature period.. It's simple, cheap, universal and so the market has formed a mainstream, not be replaced.. <BR> 2. Do not .blindly pursue the bus system for meter reading, deny the sub-wire meter.. Sub-wire meter reading (ie, remote meter pulse meter reading directly) itself is not abuse.. Some aspects of the past perfect because the product caused a bad .influence.. Past two years, these problems have gradually been resolved.. Its versatility and low cost advantage will make it a long time dominated the market.. <BR> 3. Do not blindly pursue the kind of built-in sensor- .type water meter look pretty remote.. Five years ago, many are built-in remote water meter sensor, the design of the author is no exception, but pretty difficult to use.. By the external sensor built into it is being applied forced out .of practice, some ways an improvement, the appearance of a beautiful business here can not be bothered.. <BR> 4. Wireless remote water meter pilot should start gradually.. <BR> Proved that the products in the remote meter, .regardless of technology, product, or process, and can achieve any substantial progress a little bit is very easy.. Who wants to solve all problems in one step, one who will put myself into situations, and even premature eliminated.. This requires many .technical staff of concentrated solid, rather than the operation of business early on ...

【 Weak current College 】 screw pump selection of categories---Power By 【 China power house network 】

<br> is a positive displacement screw pump rotor pump, which is a screw pump and pump sets of teeth sealed chamber formed by the displacement of a number of suction and discharge liquid. .Screw inside the sealed chamber between two adjacent channel leakage is not as strictly theoretical sealed screw, whereas a non-strict sealed screw. .<BR> <BR> Noted in the practical application of current and relevant information, the application of a wide range of screw pump, which is characterized by a smooth flow, pressure pulsation, a self-absorption capacity, low noise, high efficiency, long life, .small size, reliable. .Outstanding advantage is the transmission medium does not form a vortex, can deliver a wide range of viscosity of various media, both can transport a variety of viscosity of lubricating or corrosive media, can also transport all kinds of non-Newtonian fluid viscosity, but also .can be fluid with gas, solid-liquid mixed transportation. .It is widely used in offshore platform construction, petrochemicals, shipping, electrical, mechanical hydraulic systems, food, paper, sugar, military, and sewage treatment and other industrial sectors. .Al Wheeler German sales manager as saying: "Nowhere in the world media, is the screw which can not be delivered." <BR> <BR> Said screw pump can transport any media. .Does not mean that a particular screw pump can transport all of the media, but by the media, the number of features and performance parameters required can choose different types of screw. .Usually divided by the number of screw screw screw pump, two, three and five screw pumps, each with advantages, promote the use of screw must be given the choice, only the full use of its own characteristics, in order to better .implementation of energy, materials, increase efficiency or to meet some special requirements. .<BR> <BR> Sets of single screw pump is a non-metallic elastic material (usually rubber) system to do, in the hole-like spiral groove, spiral metal it with a number of the sealed chamber formed between the screw .. .Metal screw for eccentric rotation, the sealed chamber from the pump to move the location of low pressure high pressure zone to complete the inhalation, the pressure discharge of liquid and the formation of the whole process. .In addition to general media, the single screw pump can transport the suspension and the metal particles, including fibers and other special media. .In dealing with sewage, mud, the commonly used single screw, usually working pressure is not high. .<BR> <BR> Traditional twin-screw pump is a non-strict sealed pump, made by metal material comprising a two phase pump cut the cylindrical cavity, each cavity of the two screw meshing, meshing .screw sets and screw in the pump profile is formed between a number of seal cavity. .Screw rotates, the sealing area of low pressure from the pump chamber shifted to high-pressure zone. .A single-head screw, there are double helical screw pump, the lubricating medium, if the helix angle is large enough, the main vice screw screw can be driven directly. .If coupled with synchronized gears, in theory, be no contact between the two screw. .Although not strictly traditional twin-screw pump seal, work pressure is not high, but very wide viscosity range transport of various media, you can transport all kinds of non-Newtonian fluid viscosity can also be fluid with gas, solid-liquid mixed transportation .. .Therefore, the industry is great interest in its place, especially in petroleum, chemical industry. .<BR> <BR> Is strict in theory, three screw-type sealing screw. .In textbooks, usually as a typical screw to be introduced. .Three screw pump is a metal pump comprising the main screw driven screw drive consisting of two. .Each has two helical screw, pump sets and screw in the number of the sealed chamber formed between the screw rotates, the sealing area of low pressure from the pump chamber shifted to high-pressure zone. .Three screw pump maximum operating pressure up to 30MPa, transmission medium is clean, non-corrosive lubricant, for special occasions can deliver high-viscosity, non-corrosive media (such as: ink, glue, etc.). .1:3:5 ratio of the structure of the three screw size constraints and other reasons, three screw transmission medium viscosity range is limited, generally limited to lubricating medium. .<BR> <BR> Five screw-type sealing screw usually non-strict. .A main vice screw driving four screws, each screw has two spirals. .As the pump chamber section of a larger unit over-current, and thus a large amount of media delivery. .Five screw 0.8MPa working pressure is usually less often restricted in installation size special occasions (such as: ship, ships, etc.) for the fuel pump. .<BR> <BR>.

Weak current College】 【inverter technology in application of parsed --- energy saving Power By】 【China power house network.

<br> I. introduction <br> <br> In industrial production and product manufacturing, fans, pumps is wide; its energy consumption and such as valves, bezel of throttling losses associated equipment as well as maintenance and repair costs to the production cost .of 7% to 25%, is a small production expenses. With the deepening of economic reforms, increasing competition in the market; energy consumption has become a lower production costs, improve product quality in one of the important means. But in the early 1980s ., developed inverter, precisely the industrial production automation development requirements, ushered in a new age of intelligent machines. Changed the ordinary motor can only run in constant speed of stale mode, making motor and drag the load without any change of circumstances that can follow the .production process for adjustment of the speed of output, thereby reducing motor power to the system running efficiently. In the late 1980s, the technology into our country and get promoted. Now in the electric power, metallurgy, petroleum, chemical industry, papermaking, food ., textile and other industries of electric transmission equipment in the actual application. At present, the inverter has become a modern power transmission technology, one of the main directions of development. Excellent conversion performance, significant energy saving effects and improve existing equipment operating conditions, .improve system reliability and safety of the equipment utilization, extend equipment life and other advantages as field of application is expanding. <br> <br> II. Summary <br> <br> Usually in industrial production, product processing and manufacturing equipment mainly used .in fan combustion system, drying system, cooling system, ventilation system, etc, depending on production requirements the furnace pressure, wind speed, air flow, temperature, and other indicators for control and regulation in order to adapt to the technological requirements and operating conditions .. The most common means of control is adjustable throttle, bezel opening size to adjust the managed object. In this way, regardless of the size of the production demand, fan to speed and operating changes you made to air door, bezel of energy saving loss .consumed. In the production process, not only control accuracy is limited, but also caused a lot of energy to waste and equipment loss. Resulting in increased production costs, shorten equipment life, equipment maintenance, high maintenance costs. Pump equipment in production areas also .has broad application space, pump stations, water storage tank for water drainage system, industrial (oil) circulatory system, heat systems use centrifugal pump, axial-flow pumps, gear pumps, piston pumps and other equipment. Also, depending on production requirements are .often adjust valves, return valves, globe valves, throttle devices for flow, pressure, water level and signal control. In this way, not only cause a lot of energy, waste, pipelines, valves etc airproof performance; also speeded up the pump, .valve wear and cavitation, serious damage to the device, affect production, endanger the quality of products. Ventilator and pump equipment most used asynchronous motor direct drive way, start current, mechanical shock, electrical protection of poor shortcomings. Not only affects the service life .of the device, and when the load has a mechanical failure not protecting device, instant action often pump damage at the motor also burned for phenomena. In recent years, the urgent need for energy saving and product quality requirements, coupled with a frequency converter ( .inverter), easy operation, maintenance, control, high precision, and can achieve high functional features such as; thus adopt inverter-driven programmes began to gradually replace throttle, bezel, valve control programmes. Frequency technology's basic principle is based on the motor speed .and power supply input frequency proportional relationship: n = 60f (1-s) / p, (-n, f, s, p represents a speed, input frequency, motor slip, motor pole logarithm); by changing the motor power supply frequency .to change the motor speed. Inverter is based on the principle of the use of AC-DC-AC power converter technology, power electronics, micro-computer control technologies in one integrated electrical products. <br> <br> III. analysis of energy .saving <br> <br> By fluid dynamics of basic laws known: fans, pumps are squared torque load and speed the flow Q, n and H and the shaft power pressure P has the following relation: Q ¡ .ø n, H, P ¡ .ø ¡ .ø n2 n3; that is, the flow is proportional to the speed, pressure and speed proportional to the square of the shaft power and speed is proportional to the cube. To a water pump, for example, its export pressure head for H0 (export .pressure head, pump inlet and outlet pipe of the static pressure difference), rated speed to n0, valve fully open resistance possession as r0, rated operating conditions and the corresponding pressure as H1, export flows to Q1. Flow-pressure curve speed-as .shown in the figure below. In-the-spot control, you typically use the pump speed run export valve control flow. When the flow is reduced from 50% in Q1 to Q2, the valve to open degree decreases so that the network becomes the .resistance characteristics by r0 r1, system operation points along the direction I from point a to point b; pressure under its throttling of H2 H1 becomes. The actual value of pump shaft power (kW) by the formula: P = Q · H / ( .η η bc ·) × 10-3. Where p, Q, c, H, η η b represent power, flow, pressure, water pump efficiency, gearing efficiency, direct drive of 1. Suppose the total efficiency (η η bc · .) is 1, the water pump from point a to point b, motor power savings and the area of AQ1OH1 BQ2OH2. If you use the pump speed means change, when the flow speed n from Q1 to Q2 is reduced by 50%, then the .network resistance characteristics for the same curve r0, system operating point II along the direction from point a to point C, pump running more reasonable. In valve fully open, only network resistance, the system meets the requirements of the site, the energy will flow .. At this point, motor power savings and the area of AQ1OH1 CQ2OH3. Compare with valve opening adjustment and pump speed control, obviously using the pump speed control more effective and reasonable to have significant energy saving effects. In addition, diagrams can also be seen .: valve regulation would make the system pressure H, this will pipe and valve sealing performance threat and destruction; and speed regulation, the system pressure H will pump rotational speed nLower and lower, it will not have adverse effects on the system. From the above .comparison is difficult for us to find out when the scene needs to pump flow rate from 100% to 50%, with speed regulation than the original valve regulated savings BCH3H2 corresponding power sizes, energy-saving rate in more than 75%. <br> .<br> Similarly, if you adopt the frequency conversion technology change pumps, fan speed control site equipment pressure, temperature, water level, and other process control parameters, you can draw a system control characteristic curve drawn above the results of the comparison. Ie ., the use of inverter technology to change the motor speed method than using valves, regulating more energy-efficient economy bezel, equipment operating conditions will be improved significantly. <br> <br> 4. energy saving calculation <br> <br> For .fans and pumps of the equipment in the frequency of energy-saving effect, generally two ways to calculate: <br> <br> 1. on the basis of known fans and pumps in the different control methods of flow-load curve and scene changes .of the load operation. <br> <br> To a IS150-125-400-type centrifugal pump, for example, rated flow 200.16m3 / h, lift-equipped Y225M-4 50m;, 45kW electric motor rated power. Pump valve .adjustment and speed regulation of flow-load curve, the following diagram. Depending on operational requirements, pump continuous 24-hour run, which run every day, 11 hours, 90% <br> <br> 13 hours of running at 50% load .; year-round operation time in 3 days. The amount of electricity each year to: <br> <br> W1 = 45 × 11 (100% -69%) × 300 = 46035kW · h <br> <br> W2 = .45 × 13 × (95% -20%) × 300 = 131625kW · h <br> <br> W = W1 + W2 = 46035 +131625 = 177660kW · h <br> <br> Per unit according to 0.5 element calculation, the annual saving electricity .8.883 million. <br>.

【 Weak current College 】 video meeting system requirements---Power By 【 China power house network 】

Video conference system, refers to two or more people in different places, through a transmission line and multimedia equipment, sound, image and file information, mutual, achieve real-time, interactive communication, to accomplish the purpose of the meeting of system equipment. Video conference using something like the phone, in addition to being able to see and do you call people and language exchanges, can see their expressions and actions that are in different places, like in the same room as mutual communication.

Use video conferencing system three advantages

First of all, the video conferencing makes people like different places in the same room as the exchange of ideas, Exchange information, you can overcome space and time distance barriers, saving business travel, accommodation, entertainment expenses, save energy, to spend more time working on production work, thereby improving productivity, and make full use of resources. Secondly, the Conference system makes meeting more frequently, communication smoother, sharing information more fully, so you can make decisions more quickly. Once again, videoconferencing system allows to make decisions faster, more optimized and more participants ' views and support; no matter when and where the competent personnel, can quickly bring together decision, get more views, you can make the product more quickly to market and faster handling crisis; because the company operate more efficiently, you will get more customer feedback and customer needs to make more effective answer.

Video conferencing application

Since the video conference system gradually applied in all enterprises, mostly targeted at enterprises and business links, internal multipoint meetings and educational training. Currently, video conference system is mainly used in the following broad areas:

Remote business meetings application — the most common video service is the most widely used, apply to large group and wholly foreign-owned enterprises in business activity soared, gradually use video conferencing to organize some business negotiation, business management, business negotiations, products, remote business guidance and remote Conference within the company.

Distance learning applications-use video conferencing system carrying out teaching activities so that more and more large range of students to listen to excellent teaching, millions of students through interactive TV conference system. In addition, remote training in the major companies are more and more attention.

Telemedicine applications — use video conferencing system business realize Central Hospital and the hospital is difficult and complicated diseases for consultation, treatment and care, on the base of medical training of medical staff, etc. High-quality video conferencing enable doctors, nurses in different places at the same time, collaborative work possible.

Project teamwork application – for remote management of a very good tool that features resource sharing. Project group members for remote collaboration, enable geographically separated teams with greater speed and flexibility to get organized.

Government Executive-application-video conference system is a modern meeting faster method, which enables immediate superior file content, so that the child was placed face-to-face discussions and a profound understanding of the spirit, so that higher level instructed timely implementation.

Enterprise demand for video conferencing market been liberated

Early, video conference system is limited to the Government and the electricity, telecommunications, and financial monopoly industries use. These systems are mostly built based on H.320 agreement, while the cost is run in the network, and network construction investment is huge, the large number of enterprises will be excluded from the application of the threshold.

After entering the 21st century, "high efficiency" hasbecome the focus of the modern enterprise stressed. Enterprises have too many travel expenditures included in the cost reduction plan, and how to improve communication efficiency, shortening the decision-making time, improve enterprise management capabilities put on the agenda. Furthermore, the "9.11" and the two SARS events stimulate videoconferencing systems market transformation of two major factors, since then, the Group began large-scale procurement and use video conferencing system, the needs of the enterprise, making video conferencing market growing cake.

According to the United States statistical results IDC: in recent years, the video conferencing system of the dramatic increase in demand. 2003 video conferencing market around 10 billion; 2004 global market capacity of up to $ 4 billion, is the growth of video conference system "inflection point"; in 2005, China's video conferencing market growth rate will remain at 32%!

Video manufacturers reduce the threshold using video conference system

Early Chinese market demand led to the germination of the great Ted, POLYCOM and other foreign corporations entering China, due to an earlier entry into the market, very high brand recognition. The product has several features: you can only run in the network, the budget is very high, about 500 000-5 000 000 between enterprises use effect is clear, and greatly enhanced competitiveness.

Later, more and more businesses are committed to developing business video conferencing system, most of the enterprise consumer groups do not have special characteristics, headquarters and branches through a broadband Internet connection, a relatively low budget features development products. These problems can be solved, its price will be more closely linked to the needs of the enterprise, its initiation of the market will also be larger.

Weak current College】 【inverter air conditioner with optional skills --- Power By】 【China power house network.

<br> <br> <br> The so-called "inverter air conditioner" is the traditional "fixed-frequency AC" compared to the concept. As everyone knows, China's voltage is 220 volts, 50 Hertz, in which the conditions of .air conditioning as "fixed-frequency air conditioning". Due to the power supply frequency cannot be changed, the traditional fixed-frequency air conditioning compressor speed is essentially the same, depending on its constantly "open," compressor to adjust the room temperature, .its an open a stop between easily - at room temperature, and consume more power. By contrast, "inverter air conditioner" power converter changes the compressor, adjust the compressor speed frequency. Depending on how fast the compressor speed reaches room temperature control, temperature .fluctuations, the purpose of the small, low power consumption, its comfort. While the use of frequency control technique for frequency conversion air conditioning, automatic selection according to the ambient temperature of the heating, cooling and dehumidification operation modes, make room in the short .time up to temperatures and low-speed, low-power state to smaller temperature fluctuations, enables fast, efficient and comfortable temperature effects. <br> <br> Power supply frequency is high, the compressor speed, air conditioning and refrigeration (heat) .and the large amount; less frequent when the power supply, air conditioning and refrigeration (heat) in the small. This is the so-called "principle of constant-frequency". Inverter air conditioner is its frequency converter, inverter is the 1980s came .out of a high-tech, it passed to the current conversion for motor operation frequency of automatic control, put a fixed grid frequency 50 Hz to 30 to 130Hz changes frequency, so that the air conditioning had a new revolution. At the same time, .also enables power voltage range reaches 142V-270V, completely solved because voltage instability caused air conditioner does not work properly. Inverter Air Conditioner every time when you start to use, usually let air conditioning for maximum power, maximum air flow for heating or cooling, .fast approaching the set temperature. Because the inverter air conditioner operating frequency by increasing compressor, increases in temperature of heating capacity, maximum heating capacity may reach the same brand, same level air conditioner 1.5 times, temperatures can still maintain good heating effect. In addition ., General split machine only four-shift the wind speed can be adjusted by inverter air conditioner indoor fan automatically at run time, the speed will vary with the compressor working frequency in 12 crosspiece wind speed range, because the fan speed and ability to meet the .air conditioner is more reasonable to achieve low noise quiet running. When the air conditioning high power operation, fast approaching the set temperature, the compressor is in low-speed, low power state operation, only the power required to maintain the set temperature. This .will not only temperature stability, and protects compressor frequent stop letting the attenuation of life, and a significant decrease in power consumption, high efficiency and energy saving. <br> <br> "Inverter air conditioner" using more advanced technology, a small startup ., voltage, low voltage and low-temperature conditions to start, which for some regions due to voltage instability or winter indoor temperature is relatively low but air conditioning is difficult to start, have a certain effect. Due to the implementation of a compressor with continuously .variable, it can also be adapted to more large refrigeration heating needs. However, the "inverter air conditioner" price is usually a "fixed-frequency air conditioning up to around $", so to buy "inverter air conditioner", note the following .: <br> <br> A, DC inverter 48 per cent is generalize <br> <br> China Refrigeration Institute of experts pointed out that DC's two electrodes of polarity is fixed, there is only one flow of electric current, no alternative, .no frequency at all, on what frequency? current market promotion of so-called "DC inverter air conditioner" actually is DC air conditioning, it's DC drive technology is far better than FM technology. But the marketing personnel in order to take full advantage of .people's minds thinking-in, we unhesitatingly to it on the original frequency cap, then make a joke. <br> <br> According to reports, DC only after a voltage conversion, energy loss is less than FM conversion. In addition, because .the DC motor rotor is permanent, and save the three-phase AC induction motor rotor current consumption, so that from the power grid power supply to the motor that paragraph electrical efficiency than FM high speed mode, saving some energy. But individual manufacturers but for .this point of the internal control system of energy-energy for the whole machine to exaggerate, and 48 per cent of the energy-saving. Experts said the Festival energy not depends primarily on the refrigeration system design and configuration, depending on the size of the .coefficient of refrigeration systems. It is not difficult to see that the constant speed improvements to speed air conditioner air conditioner primarily to improve the way its Auto-adjust to enhance the quality of the machines, instead of saving energy. However, in particular, the .speed is just improve the quality of the air conditioner is running a Foundation, and the real improvement also depends on the matching of the refrigeration system. Adjusting system of cooling capacity of the critical part is throttling decompression components, if you do not remove it from .the constant damping by changed to adapt to the speed range, adjustable damping of electronic pressure reducing valve <br> (Expansion valve), then that would speed air-conditioners have little meaning or even superfluous consumption internal conversion of electrical energy required. Modern air .conditioning efficiency than conventional in 2.6 - 2.9, very little beyond 3.0. Therefore, the energy-saving 48 percent of propaganda is not exact. <br> <br> Second, the "Payroll frequency" is not a price which is lower costs < .br> <br> "Payroll frequency" air conditioning price than most "frequency" air conditioning low price around $ mainly reduced costs. First of all, now inverter air conditioners are basically double rotor, and most were imported compressors, and "Payroll frequency ."with Shanghai Hitachi single rotor compressor, this post probably cost money. Secondly, the throttling device is divided into two kinds, one kind is the expansion valve, a capillary. General fixed-frequency AC with capillary, inverter air conditioner uses the expansion valve .. "Payroll frequency" using capillary, capillary cost more than ten dollars, while the expansion valve is a two hundred dollars. Third, frequency converter, General inverter machine imported, "Payroll frequency" is made. This point, in addition to the cost .difference, there also exist on the frequency ranges and narrow. The fourth is "Payroll frequency" Is a single cold winter in frequency machine, do not use the common four-way valve is turned into a pass-through, a four-way valve .is more, these add up to an estimated cost reduced to 800 Yuan. <br> <br> 3. not to maximum cooling capacity as purchasing criteria <br> <br> Inverter air conditioner and general air conditioning in the selection is different. .In the purchase, according to the size of a room to determine the size of the power inverter air conditioner instead of to the maximum cooling capacity as their purchasing criteria. Because the inverter air conditioner not work long hours in maximum cooling condition, its maximum cooling .capacity is limited to a specific area of the room for a short period of time can reach of cooling capacity, but it is important to avoid in the area access. Experts suggest that consumers may (145-175) W m2 buy inverter air conditioner. .<br> <br> <br>.

【 Weak current College 】 how to choose the most suitable video conference system?

Video conference system and hardware, software, networks are closely related, every business is different from the actual situation, the required video conference system are not the same, comprehensive analysis and communicate with manufacturers to choose the most suitable video conference system.

Divided by network platform, video conference system can be divided into based on the private network video conferencing system, based on a mixed network and the Internet public network video conferencing system. By constructing a modal split, video conference system can be divided into software video conferencing and hardware video conference, video conference system major general portfolio expansion MCU multipoint controller/meeting room Terminal \PC desktop Terminal/phone access gateway (PSTNGateway) \Gatekeeper (gap), etc. Press Conference-quality Division, and standard definition video conference system and high-definition video conferencing system.

Laying network while it is possible to guarantee meeting quality, but much higher input costs, on the development of SMEs is not appropriate. In fact, the Internet has developed very well, even the cheap ADSL line can also provide more bandwidth, 384Kbps such bandwidth fully able to meet the video conferencing application clear and smooth. Therefore, generally choose public Internet suffice.

Using purification of PC-based software solutions while meeting the software itself costs is not high, but each room is also equipped with a dedicated PC, separate video and audio capture device (e.g. USB camera and headset) and the operating system and other related infrastructure software, installation, maintenance overhead, taken together, its cost is low. And pure hardware solution can not only perform high quality meeting and can be highly integrated integration all the features of the terminal equipment is complete without the other with other hardware and software facilities, the plug and play, using simple, maintenance-free, therefore its comprehensive cost than pure software cheap. Overall, pure software more suitable for the individual Office deployment (based on an existing Office PC), pure hardware conference room is suitable for deployment.

2007 SD video conferencing is still the mainstream market, occupying 93.60% market share, which represents the future of technology trend of high-definition video conferencing only 6.40% market share. High-definition video conferencing system advantage manifests itself in several ways: high resolution formats have increased the number of pixels can improve picture quality, make big screen picture more clear, smooth, and smooth clear video quality, high-quality sound effects can enhance attendee's conference experience to help participants to focus on the content of the Conference itself; at the same time, the high definition picture can make large screen image also has a clear video images that more participants appear on the screen, allows more attendees; high definition of high resolution images, to clearly show the details of the content, especially in the graphics operations (such as design drawings, animated discussions, topographic maps, etc.), relying on the Visual communication remote personnel, have great benefits. And compared to standard definition video conference system, costs more, on network requirements are higher.

Enterprises should be a comprehensive analysis of the company's actual needs, including input costs, network bandwidth, device management, choose the most suitable for their own video conference system.