What does light amplitude mean?

Question 1: What symbol is used to indicate the illumination amplitude of solar cells? The symbol of irradiance is e.

The unit is watts per square meter.

Hope to adopt

Question 2: Why should the standard conditions for testing solar cells be stipulated? Because the measured value is not only affected by the performance of the battery itself, but also by the current standard conditions such as temperature, illumination amplitude and angle. How to compare different conditions to make the test meaningless.

Question 3: What is the meaning of LPD value in building electricity? LPD limit standard for lighting design

GB50034-2004, Design Standard for Building Lighting, was officially implemented on June 65438+February 1 day, 2004, and it has been nearly five years since then. This standard has greatly improved the lighting level in the workplace, which is not only in line with international standards, but also meets the needs of social development. Article 6. 1.2 ~6. 1.7 of this standard imposes mandatory restrictions on the lighting power density (LPD) of six types of buildings except residential buildings, such as offices, businesses, hotels, hospitals, schools and industries. LPD is defined as the installation power of electric light source and ballast per unit area, and the unit is W/O. In this standard, the LPD index has been raised to the position of mandatory provision, which reflects the country's emphasis on energy saving. In this standard, it is strongly recommended to use high-efficiency tricolor fluorescent lamps, low-energy high-frequency electronic ballasts and energy-saving inductive ballasts, so as to greatly improve the lighting standards of places without increasing power consumption or only slightly increasing power consumption. The mandatory regulation of LPD upper limit makes it impossible to continue to use incandescent lamps or thick tube fluorescent lamps and ordinary ballasts in many occasions. Otherwise, LPD will exceed the standard and violate the strong rules. Although the standard has been implemented for nearly five years, many problems will still be found in the implementation process. The following problems are often found in drawing review:

First, some designers do not calculate the illuminance according to the sequence of lighting design, but use the backward method to design lighting. For example, in general office standards, the current value of LPD is 1 1 W/O, and the target value is 9 W/O, so it is11w/o. Some designers calculate the total power of the room according to the room area, and then calculate the required lamp flow according to the selected lamp power, and then arrange them to complete the design. The whole process seems simple but ignores an important problem: the characteristics of lamps are not considered. If light sources and lamps with low light efficiency are used in the design, the actual illumination of the room will be lower than 300Lx. Although it does not violate the mandatory provisions, if it is converted to meet the requirements of 300Lx, its LPD will definitely exceed the standard, exceeding 1 1w/O, which violates the strong bar. However, when optical flow and optical flow with high light efficiency are used, for example, the illuminance of ordinary office may reach 500~600Lx, which exceeds the standard value of 300Lx, resulting in waste of energy and increase of project cost. Because the influence of different light sources and lamps is not considered, the designed illuminance is actually imaginary, and it is difficult to really meet the requirements of GB50034-2004 standard. This design seems to meet the requirements of LPD limit, but we don't know what the illumination is.

2. LPD in the standard is defined as the lighting installation power per unit area (including light source, ballast or transformer), and the unit is watts per square meter (W/O). However, many designers only consider the electric power of electric light source and ignore the power of ballast, which is related to the type of ballast and depends on the type of ballast used. The new national standard requires that the yellow light should be equipped with electronic ballast or energy-saving ballast. Electronic ballast and energy-saving inductive ballast have their own advantages, but in terms of development, electronic ballast has more advantages, higher energy efficiency, no stroboscopic and no noise. There are two types of electronic ballasts: H type and L type. L-type electronic ballast with low harmonic content should be selected, and its power factor is above 0.9, so it is not necessary to compensate again. However, the power factor of energy-saving inductive ballast is only 0.5, and devices need to be added to make the power factor reach above 0.9. For other gas discharge lamps, such as halogen lamps and high-pressure sodium lamps, energy-saving inductive ballasts should be selected and compensated to meet the requirements of power factor above 0.9.

Three. In lighting design, the types and specifications of light sources, lamps and ballasts should be determined according to the use conditions, and the horizontal storage illuminance should be calculated to meet the specified illuminance standard value, and the deviation of calculated illuminance should not exceed+10%. The calculated LPD value should be compared with the LPD value (current value) specified in the standard. If it does not exceed the requirements, the scheme should be adjusted until it meets the requirements.

The stipulation of LPD limit in GB50034-2004 standard is of great significance for improving energy efficiency and saving energy in the field of building lighting. Lighting engineering involves a wide range and occupies a considerable proportion in energy consumption. Strict implementation of the LPD limit in the standard and careful design will certainly help to save energy. ...& gt& gt

Question 4: What does ISO mean in a camera? ISO: sensitivity

Iso (International Standards Organization) international standard agreement: film sensitivity to light; Low sensitivity refers to films below ISO 50, medium sensitivity refers to ISO 100~200, and high sensitivity refers to films above ISO 400.

When using traditional cameras, we can choose negatives with different sensitivities (speeds) according to the brightness of the shooting environment. For example, iso200 can be used in cloudy environment, and iso400 or higher can be used in concert environment. Digital cameras have a similar function, which changes the iso value by changing the amplification factor of the signal amplifier in the photosensitive chip. However, when the iso value increases, the amplifier will also amplify the noise in the signal and produce a coarse-grained image.

A long time ago, there were contacts on the film that allowed the camera to automatically identify ISO. If you use a camera with the function of automatically identifying ISO film (there are metal beads identifying ISO in the film box), there is no need to set ISO, and the camera will automatically measure light according to the ISO value of the film. If you don't have this function, you need to set it manually, so some cameras have ISO dials on them.

Generally speaking, the price of ISO 100 film is relatively cheap. In addition to the higher price, the higher the ISO, there is another disadvantage, that is, the imaging quality is not as high as that of low ISO film. But sometimes in order to get higher shutter speed, the quality of the film will be sacrificed to use high ISO film.

ISO of digital camera is an index similar to film sensitivity. In fact, ISO of digital cameras is realized by adjusting the sensitivity of photosensitive devices or merging photosensitive points, that is, by improving the sensitivity of photosensitive devices or merging several adjacent photosensitive points.

Photosensitive devices have a kind of reaction ability and are fixed. Improving the ISO of digital cameras can be achieved in two ways: 1, forcibly improving the brightness and contrast of each pixel; 2. Use multiple pixels to complete the task that only needs one pixel.

It can be seen that the image quality loss of digital cameras after upgrading ISO is great, especially when the area of photosensitive devices is small, upgrading ISO is simply fatal. The CCD photosensitive area of FZ 10 or FZ20 is pitifully small, only 1/2.5 inches. If the ISO is upgraded, kill it. Therefore, some SLR digital cameras can still get good image quality after several ISO upgrades. This is because the CCD sensitive area of these cameras is relatively large, but it is not the scope of our discussion.

Depth analysis of ISO sensitivity of digital camera

I believe that the advantages of digital cameras are needless to say these days, but some open technologies inside digital cameras are still little-known secrets for ordinary digital enthusiasts. Slightly experienced color lovers can realize that in daily shooting, if the ISO sensitivity is improved, the originally dim environment can also jump on the LCD brightly. Although the lovely manufacturer has prepared 50 to 400 adjustable files for us, few friends really set it to ISO400. However, although the image quality of ordinary digital cameras is not good under ISO400, we find that digital SLR is still intact even if it is as high as ISO800.

How to realize random adjustable ISO sensitivity of digital camera? Feiyu answered these seemingly responsible questions in simple terms in line with the people-oriented scientific and technological concept.

First, the concept of ISO in the film age

ISO is the standard of film photosensitive speed formulated by the International Organization for Standardization according to the chemical reaction speed of film to light. As early as the film era, our photography life silently followed this industry standard. When buying film, the words ISO 100, ISO 200 and ISO400 will be marked on the package. The larger the ISO value here, the faster the photographic speed of the film, which means the film with high ISO value. Only weak light is needed to make the film produce an image, so that a smaller aperture or a higher shutter speed can be used under the same light brightness, that is, the sensitivity is inversely proportional to the required exposure.

For example, the exposure speed of ISO 100 is twice that of ISO 50, because under the same circumstances ...

Question 5: How to calculate the conversion efficiency of monocrystalline silicon wafer? 5 points: solar cell efficiency = (open circuit voltage * short circuit voltage * filling factor)/(cell area * illumination amplitude) * 100%.

Illumination-based on AM 1.5, i.e. 1000W/m2.

Stem current ratio -――Irev & gt；; 6 Proportion of battery chips

Proportion of inefficient tablets-p156 eff Question 6: What does the plant Jinguning look like?

Category whole grass

The source is the whole grass of the labiatae plant Ajuga.

It can be harvested all year round, and it is better to harvest at flowering stage. Fresh or dry.

Bitter, cold and nontoxic.

Indications: clearing away heat and cooling blood, clearing away heat and reducing swelling.

Indications for sore throat; Pulmonary heat hemoptysis; Traumatic swelling and pain

The ecological environment is born in grasslands, forests or valleys and streams at an altitude of 340-1800 m.

Harvesting and storage: harvesting, washing, drying or rare use when flowers bloom from May to August.

Mostly in waterside wetlands or grasslands and forests. Distributed in Hebei, Shandong, Henan, Shanxi, Shaanxi, Gansu, Ningxia, Hubei, Sichuan, Zhejiang and other places.

Ajuga-animal and plant morphology

Perennial herbs. Adult plants are 25-40 cm tall, with erect stems, usually hairless, and gray-white villous young parts. Leaves short-stalked, ovoid-elliptic to narrowly elliptic, base cuneate, decurrent, apex obtuse or acute, margin with irregular heavy teeth, ciliate, both surfaces scabrid or sparse. Spike cymes are terminal and consist of densely arranged multi-flowered cymes, generally 5- 10 cm long; Bracts are large, leaflike, sometimes purplish red, oval, and 1- 1.5 cm long; Calyx funnel-shaped bell-shaped, calyx teeth 5, hairy, neat; Corolla purple, with blue stripes, crown tube longer than calyx, hairy ring near the base of tube, 2-lipped crown, short upper lip, erect, rounded apex, slightly notched, large lower lip, elongated and 3-lobed; Stamens 4, 2 strong, slightly more than corolla; Style apex 2-lobed. Fruit nutlets are oblong or ovoid-trigonous, with reticular wrinkles on the back, bulging in the middle of the abdomen, and large fruit umbilicus, occupying almost the whole abdomen. The cotyledons of seedlings are broadly ovoid, the apex is slightly concave, the leaf base is round and has a long handle; The hypocotyl is extremely developed, pink, the epicotyl is underdeveloped, the primary leaves are opposite, obovate, the apex is blunt, the leaf base gradually narrows, the leaf margin is microwave-like, the ventral surface is densely pubescent, petiolate, the epigenetic leaves are similar to the primary leaves, and the seedlings are pubescent except the hypocotyl and cotyledons. The flowering period is from April to August, and the fruiting period is from July to September. Seed propagation.

Ajuga-Remarks

(1) For patients with sore throat or even fever, just use this product 1-2 times and decoct it. It can be used for treating cough due to lung heat with yellow and thick expectoration, and can be combined with expectorant and antitussive drugs such as Peucedanum praeruptorum and loquat leaves. For the treatment of heat furuncle and carbuncle, in addition to decoction, fresh herbs can also be applied externally. For traumatic bleeding, hay can be ground into powder and wrapped; To treat swelling and pain due to blood stasis, take appropriate amount of fresh grass and mash it for external application.

(2) Ajuga is also called Prunella vulgaris. Referred to as Prunella vulgaris, this is because there is a passage in the Compendium of Materia Medica in the Qing Dynasty: "The petiole is the same as Prunella vulgaris, but there are white hairs on the leaves." Hence the name. Ajuga is bitter in taste, but it has a strong effect of clearing away heat and toxic materials. In recent years, through clinical practice, it has a good effect on treating acute tonsillitis, acute pharyngitis and acute bronchitis.

Ajuga-Formula Selection

① Treatment of hemoptysis due to lung heat: five yuan for Ajuga, one or two for imperata rhizome, and one or two for rock sugar. Decoct with water.

② Treatment of tonsillitis, pharyngitis and laryngitis: Ajuga is five yuan to one or two yuan. Decoct with water. Or use four or five fresh Ajuga, add tofu and cook together, eat tofu and drink soup.

③ Treatment of traumatic injury and sprain: Fresh Ajuga grass is added with a small amount of ginger and scallion, and mashed for external application.

The method of inducing cough in mice showed that the alcohol extract of Oxalic acid from bones and muscles (1 12), flavonoid glycosides, total acid phenols, total alkaloids, crystals (I) and saponins) all had certain antitussive effects, among which flavonoid glycosides (2.5mg/ animal) and codeine (0.4mg/ animal) had similar antitussive effects. Its function is to directly inhibit the cough center. Phenol red method in mice proved that acidic alcohol extract 1 12, flavonoid glycosides, total acidic phenols, alkaloids and crystal (I) all had certain expectorant effects. Its function is to secrete cells directly from respiratory mucosa, increase secretion, dissolve acidic mucopolysaccharide fibers in sputum to some extent, and reduce capillary permeability, indicating that its flavonoid glycosides can reduce tracheal permeability during inflammation, thus playing an anti-inflammatory and expectorant role. Alcohol extract, flavonoid glycosides and alkaloids have different antiasthmatic effects on asthma in experimental animals, of which 250mg/kg flavonoid glycosides are equal to 125mg/kg aminophylline. The antiasthmatic effect is due to direct expansion of bronchial smooth muscle and strong anti-infection effect. Luteolin, the effective component of Ajuga, has antitussive effect on mice induced by 50 mg/kg gastric perfusion and 25 mg/kg intraperitoneal injection of ammonia mist, and on anesthetized cats with 30 mg/kg intravenous injection ...

Question 7: Surveillance cameras. What is scaling? Zoom is the focal length, which is a long-term problem! Is to make the objects seen by the camera far and near. Zooming is to enlarge the object you see. Can you understand this?

Question 8: What vegetables are suitable for greenhouse cultivation in winter? Greenhouse vegetable planting technology (1): greenhouse construction

(1) Type and structure of scaffolding. There are many types and structures of plastic greenhouses. At present, there are two kinds of prefabricated galvanized thin-walled steel pipes (referred to as steel pipe greenhouses) and bamboo circular arch greenhouses widely used. It is mainly used for early-maturing cultivation in spring and delayed cultivation in winter of tomatoes, sweet (hot) peppers, eggplants and cucumbers in Natsuna, as well as seedling raising and hybrid seed production. There is also a bamboo shed, which is often used alone or in combination with a greenhouse (that is, a shed is built on the greenhouse) for seedling raising and early cultivation of eggplant and melon vegetables in winter and spring.

There are two specifications for steel pipe greenhouses: one is that the center is 2.2 meters high, the width span is 4.5 meters, the length is 20 meters, and the area is 90 square meters; The other is that the center is 2.5 meters high, 6 meters wide and 30 meters long, with an area of 180 square meters. The service life is generally 15 years.

In order to reduce the production cost, bamboo shed can also be used. Scaffolding is made of bamboo or small logs, about 2 meters high and 4-5 meters wide, with a general service life of 3 years.

(2) Covering materials: Greenhouse covering materials are as follows:

1. Ordinary membrane: made of polyethylene or polyvinyl chloride, with a thickness of 0. 1mm, colorless and transparent. The service life is about half a year.

2. Multifunctional long-life film: it is made by adding proper amount of anti-aging materials and surfactants during polyethylene blow molding. The multifunctional membrane produced by Zhejiang Guangxin Plastic Factory has a width of 7.5 meters and a thickness of 0.06 mm, its service life is twice as long as that of ordinary membrane, and the greenhouse temperature at night is higher than other materials 1-2℃. Moreover, the film is not easy to form water droplets, with good covering effect, low cost and high benefit.

3, grass quilt, grass fan: woven from straw, good thermal insulation performance, is a night thermal insulation material.

4. Polyethylene high foaming film: it is a white plastic film with many bubbles, with a width of 1 m and a thickness of 0.4-0.5 cm. It is light and can be rolled up, and its thermal insulation is similar to that of grass quilt.

5. Non-woven fabric: a kind of polyester filament, which is not woven or spun. There are two kinds: black and white. They have different densities and thicknesses. The common specification is 50g/? In addition to heat preservation, it is often used as a sunshade net.

6. sunshade net: a plastic woven net. Commonly used are black and silver gray, and there are several density specifications with different shading rates. It is mainly used for sun protection and rain protection in summer, and can also be used for thermal insulation and covering in winter.

(3) Greenhouse construction: choose a place with sufficient sunshine, shelter, high dryness, good drainage and no soil infectious diseases to build a greenhouse.

(4) Maintenance of plastic film: When the film is fastened, the mechanical damage of the shed film, especially the bamboo shed, should be avoided as far as possible. Before the film is buckled, the protruding part of the frame surface should be flattened or wrapped with old cloth. When fixed with a spring, the card slot should be padded with an old newspaper. In addition, attention should be paid to avoid long-term contact between old and new films, so as not to accelerate the aging of new films. Be careful when ventilating.

If the film is frozen or exposed to the sun, it will promote aging. When the steel pipe is exposed to the sun in summer, the temperature can rise to 60-70℃, thus accelerating the aging and crushing of the film.

In the process of using the film, it is inevitable that there will be holes, so it should be repaired with glue or tape in time.

Second, the environmental characteristics and supervision

Because the greenhouse is covered with plastic film, it forms a special microclimate which is relatively closed and different from the open field. In order to cultivate vegetables in greenhouse, we must master the characteristics of greenhouse environment and take corresponding control measures to meet the conditions of vegetable growth and development, so as to obtain high quality and high yield.

(1) Environmental conditions in the greenhouse:

1. illumination: it depends on the solar radiation intensity outside the shed, the optical characteristics of the covering material and the pollution degree. The light transmittance of new plastic film is 80-85%, and the light transmittance of old film polluted by dust and soil is often below 40%. The water droplets condensed on the film surface can reduce the illumination in the shed by 10%-20% due to the diffusion of water droplets. The shed frame, the film pressing line and the frame material of tall vegetables will be blocked, so the factors that weaken the light in the shed should be avoided and eliminated as far as possible in the management of the shed.

2. Temperature:

(1) Temperature variation law: The daily variation trend of temperature in greenhouse is the same as that in open field, but the temperature difference between day and night changes greatly. There is plenty of sunshine during the day. If the temperature in the film closed shed rises rapidly, the highest temperature can reach 40-50℃, which is more than 20℃ higher than that outside the shed. The effect of warming in rainy days is poor, and the lowest temperature in the shed at night is generally higher than that outside the shed 1-3℃. The ground temperature in the shed is more stable than the air temperature, usually 10-20℃. The temperature in the greenhouse also changes with different locations. The greenhouse is horizontally distributed with high middle and low sides, so the plants in the middle of the greenhouse are often higher than those on both sides. Greenhouse is vertically distributed. The sun shines during the day, and the temperature is high and low, but it is the opposite at night and cloudy days.

(2) Inversion phenomenon: In a polyethylene-covered greenhouse, there is a cool and sunny night in winter, and the temperature inside the greenhouse is sometimes lower than that outside the greenhouse. The reason is >>

Question 9: What do you mean by succulents in full bloom? The succulents spread their cakes, which means that some succulents (especially Sedum species) become more scattered when they are wrapped. Compared with the beautiful mountains and rivers when they are wrapped, the leaves are scattered less, so they are dubbed as spreading cakes. Usually, succulents will spread the pie in the first of the following three situations. During the normal growth period, it is normal to spread cakes and spread leaves. Since it is long, it should be spread out, as long as the range is not too large, and the leaves should not be turned down. Usually, the shape of cabbage in succulents indicates semi-dormancy. Some succulents are transported by express delivery, and their leaves will be wrapped. The leaves will scatter after slow seedling, but some fans will feel puzzled. What happened to the scattered leaves of succulents? There is another situation, influenced by Korean delicious meat, which excessively pursues the ultimate beauty of meat, and also has a higher standard for spreading cakes. In this case, we should avoid spreading cakes, drink less water, get more sunshine, and abuse more meat may satisfy this pursuit. In the second case, it is common to spread cakes because of insufficient light, usually because there is too much water or insufficient light, or both. The corresponding symptom is that the leaves are unfolded, the state of the lower leaves and the upper leaves is obviously uncoordinated, the leaf center may be white, and the color of the leaves will be lighter. If you spread the pie in this case, if you ignore it, the next symptom is often futile. In order to avoid this situation, we can reduce watering and increase light. According to the spread of succulents, it can be decided whether to water them. Generally speaking, spreading leaves means that succulents feel that they have enough water. Spreading leaves enhances transpiration, transpiring excess water and wrapping it up, which is a measure to reduce water loss. The third situation, the influence of light, is an upgraded version of the second situation mentioned above, because succulents often spread big cakes. In order to avoid this situation, they are suddenly brought from the environment with little/no light to the environment with more/full light. If plants are short of water at present, it is easy to cause the leaves to soften and turn down under the big light, and droop like noodles. If there is too much water, it is easy to cause the leaves to crack. To avoid this situation, it is necessary to gradually increase the light, not to increase too much sunlight at once, water properly and strengthen ventilation. Generally, the spread of this kind of cake can not be solved in a short time, and the sunburned leaves can not be restored to their original state. We can only hope that they will find their beauty again under the careful care in the later period. This kind of symptom is easy to appear, such as Jade Butterfly, Jade Dragon Guanyin, Black Mage and so on. It can also be understood that leaves that weaken/grow in an unhealthy environment can't bear the normal maintenance environment at once. drlmeng/tandabing