Other translations of SMA

Stone Mastic Asphalt (SMA)

Stone Mastic Asphalt, referred to as SMA, is a new type of asphalt mixture structure. In Germany in the 1960s, it was called Splitmastixasphalt in German. It was introduced to the United States in the early 1990s and was called Stone Mastic Asphalt, abbreviated as SMA. In 1993, SMA was first applied on the Capital Airport Expressway in my country.

Features

SMA is an asphalt mastic composed of asphalt, fiber stabilizer, mineral powder and a small amount of fine aggregate, which fills the gaps in the discontinuously graded coarse aggregate skeleton. The asphalt mixture composed of. It is formed by filling the gaps of the stone-stone embedded structure formed by coarse aggregate with sufficient asphalt binder and asphalt mastic mortar with considerable stiffness. Therefore, it has high temperature resistance, low temperature stability, good water stability, good durability and surface functions (anti-skid, small ruts, high flatness, low noise, good visibility). SMA pavement has good durability, so it requires less maintenance work, has a long service life, and has good comprehensive economic and environmental benefits. Spinal Muscular Atrophy

SMA is the English abbreviation of Spinal Muscular Atrophy

For infants under two years old, SMA is the number one genetic disease killer

Every One in 6,000-10,000 newborns will develop SMA

One in 40 people is a carrier of the SMA disease gene

Two carriers of the SMA disease gene The probability of each offspring developing SMA is 25%

People of any age, race, and gender may develop SMA

SMA patients mainly present with muscle atrophy. Motor function is severely limited, and respiratory and swallowing muscles are affected. Respiratory failure caused by respiratory infections is the leading cause of death in patients.

There is currently no effective treatment for this disease. Experts constantly remind couples with a family history that they must first undergo genetic testing or prenatal testing to effectively prevent their babies from contracting SMA.

Heredity of SMA

How is SMA inherited?

5q-SMA is an autosomal recessive disease caused by mutations in the SMN1 (Survival Motor Neuron) gene on chromosome 5 (hence the name 5q). Offspring must inherit a defective SMN1 gene from each parent to become infected.

Because parents of children usually only have one defective SMN1 gene each, they are not infected with SMA and do not show symptoms of the disease. They are called carriers. Therefore, one SMN1 gene product is sufficient to maintain normal related functions of the human body. Almost every parent of a child with SMA is a carrier, with only 2% exceptions. Carriers will not get the disease because a normal gene is enough to maintain normal related functions of the body and make up for the deficiency of the defective gene. It is estimated that one in 40 people worldwide is a carrier of the SMA disease-causing gene.

If both parents are carriers or if one parent is a carrier and the other is an SMA patient, their offspring will have a chance of contracting the disease, and the affected children are all infected during pregnancy. The offspring of two carriers may be SMA patients, carriers, and healthy people. The figure below (Figure 4) shows the possible gene combinations that will appear in the offspring of two carriers. Every time they get pregnant:

·25% chance that the child will suffer from SMA

·50% chance that the child will be a carrier of the SMA disease gene

· 25% possibility that the child is neither an SMA patient nor a carrier

Performances of SMA

Infant SMA

1. Symmetrical muscle weakness: voluntary movement Reduced, the proximal muscles are most severely affected, and the hands and feet are still active.

2. Muscle relaxation: The tension is extremely low. When the baby is in the supine position, the lower limbs assume a frog-leg position, and the knee reflex is reduced or disappeared.

3. Muscle atrophy: mainly affects the limbs and trunk, followed by the neck and chest muscles.

4. The intercostal muscles are weak, the diaphragm is mostly uninvolved, and the movement of the diaphragm is normal. Therefore, the chest sinks during exhalation, showing contradictory breathing.

5. The course of the disease is progressive. In the late stage, the muscles controlled by the medulla oblongata atrophy, especially the pharyngeal muscles, accompanied by muscle fiber tremors. The atrophy of the pharyngeal and palatine muscles causes difficulty in breathing and swallowing, and is prone to absorptive pneumonia.

Juvenile SMA

It is a mild disease of the infantile type. It usually starts between 2 and 7 years old, sometimes or later. It starts with abnormal gait and proximal muscles of the lower limbs. Weakness, the disease progresses slowly, gradually affecting the distal lower limbs and upper limbs.

Intermediate spinal muscular atrophy

Also known as the chronic infantile form, the onset is 3-15 months after birth. It begins with proximal muscle weakness, then spreads to the upper limbs, and the disease progresses. Slowly, facial muscles are often not affected.

Juvenile dominant muscular atrophy

This type is a special type of dominant genetic disease. It usually starts at the age of 3-4 years and mainly manifests as proximal muscle weakness and Atrophy, the condition is mild, does not affect life span, and you can live a normal life.

Middle-aged men

The symptoms include weakness in the movement of the hands, atrophy of the intrinsic muscles of the hands, and deformities of "claw-shaped hands" and "ape hands". Difficulty in buttoning clothes, picking up small objects, and writing. Later, the muscle weakness spreads to adjacent muscle groups, involving the arms and shoulders, and then progresses to the lower limbs. There are also cases where the disease starts in the feet and then spreads to the lower limbs and then the upper limbs. Muscle atrophy develops symmetrically and weakly, sometimes involving only one hand. Decreased muscle tone and weakened tendon reflexes correspond to the affected muscles. There is no sphincter dysfunction, and pathological reflexes often do not appear, but can be seen in frequent fasciculations. Fasciculations can occur at any location, and can be induced and aggravated by cold, mood swings, or mechanical stimulation. During the course of the disease, there was no spontaneous pain or abnormal sensation. Glossary muscle atrophy and soft palate dyskinesia accompanied by pronunciation and swallowing symptoms were rare. Radio antenna interface

SMA is the abbreviation of Sub-Miniature-A. The full name of the SMA antenna interface of commonly used wireless routers/wireless network cards should be SMA reverse polarity male, that is, the antenna connector has threads inside. The inner contacts are pins (one end of the wireless device is threaded on the outside and the inner contacts are tubes). Wireless devices with this interface are the most popular. More than 70% of APs, wireless routers, and more than 90% of PCI interface wireless network cards use this interface. This interface is moderately sized, and many devices such as handheld walkie-talkies also use this interface. type, but the pins and tubes inside are the opposite of standard SMA wireless devices. Wireless APs and wireless routers using this interface include most civilian equipment. TP-LINK, DLINK, Netgear, Belkin and other brands basically use this interface as long as the antenna is detachable. The antenna interface of SMA should be SMA, and SMA and RP-SMA are different. There are many types of SMA. The difference in polarity is that one is called "SMA" and the other is called "RP-SMA". The difference between them is: the standard SMA is: "external thread + hole", "internal thread + needle" ", RP-SMA is: "external thread + needle", "internal thread + hole".

SMA-J or SMA male is called the standard SMA male connector. SMA-K or SMA female is called the standard SMA female connector.

It is a typical microwave high-frequency connector . The highest frequency it uses is 27GHz.

SMA connector is a miniature connector that can be used up to 18GHz/26.5GHz. It has significant characteristics such as high mechanical strength, high durability, high reliability and low VSWR. SMA connectors are the best choice under various usage conditions of micro circuits including sealed structures. SMA connectors can be used in various situations. For example, measurement and testing, mobile communications, electronic equipment, etc.

SMA main performance indicators:

1). Characteristic impedance: 50 Ω

2). Frequency range: with flexible cable 0~18GHz

With semi-flexible and semi-rigid cables 0~26.5GHz

3). Contact resistance: inner conductor ≤3.0m Ω

Outer conductor ≤2.0m Ω

4). Insulation resistance: ≥ 5000M Ω

5). Dielectric withstand voltage: 1000V

6). Voltage standing wave ratio: with flexible cable ≤ 1.15+0.02< /p>

With semi-flexible and semi-rigid cables ≤ 1.10.02

7). Durability: 500 times

8). Implementation standard: MIL-C-39012 Styrene-maleic anhydride copolymer

SMA: Styrene-maleic anhydride copolymer; styrene-maleic anhydride copolymer

Styrene Random polymers of maleic anhydride and maleic anhydride, thermoplastic resins. The latter contains 5% to 30%, has good impact resistance, is colorless and transparent, has good rigidity and dimensional stability, is resistant to general chemicals, and is not resistant to concentrated alkali, ketones and ester solvents. The glass transition temperature is 114°C, the tensile strength is 36~56MPa, the flexural modulus is 2200~3240MPa, and the Izod notch impact strength is 21~107J/m. Thermal distortion temperature is 101~118℃. It is often produced by adding an appropriate proportion of styrene and maleic anhydride to an organic solvent and performing free radical solution polymerization. It can be used as automobile dashboard and interior parts, household appliance parts, etc. Used as adhesive, paper enhancer, protective colloid, etc.

standard methods agar (SMA) standard agar medium Shanghai Maple Automobile SMA, Shanghai Maple Automobile = SMA

Shanghai Maple Automobile belongs to Geely Automobile Group Shape Memory Alloy ( Shape memory alloy)

In 1932, the Swede Olander first observed the memory effect in gold-cadmium alloy. That is, after the shape of the alloy is changed, once it is heated to a certain transition temperature, it changes shape again. It can magically change back to its original shape. People call alloys with this special function called shape memory alloys.

Memory alloys have only been developed for more than 20 years, but due to their special applications in various fields, they are attracting worldwide attention and are known as miraculous functional materials.

There are many successful examples of memory alloy applications in the aerospace field. Huge antennas on satellites could be made from memory alloys. Before launching an artificial satellite, the parabolic antenna is folded and installed into the satellite. After the rocket is lifted off and the artificial satellite is sent to the predetermined orbit, it only needs to be heated. The folded satellite antenna will naturally unfold and restore its parabolic shape due to its "memory" function.

Memory alloys are widely used in clinical medical fields, such as artificial bones, bone fixation and compression devices, orthodontic devices, various intraluminal stents, embolization devices, cardiac repair devices, and thrombus filtration devices, interventional guidewires, surgical sutures, etc., memory alloys are playing an irreplaceable role in modern medical care.

Memory alloys are also closely related to our daily lives. Just take the spring made of memory alloy as an example. If you put this kind of spring in hot water, the length of the spring will immediately extend, and then put it in cold water, it will immediately return to its original shape. The shape memory alloy spring can be used to control the water temperature of bathroom water pipes. When the hot water temperature is too high, the memory function can be used to adjust or close the water supply pipe to avoid burns. It can also be made into fire alarm devices and security devices for electrical equipment. When a fire occurs, the spring made of memory alloy deforms and activates the fire alarm device to achieve the purpose of alarming. A spring made of memory alloy can also be placed in the heating valve to maintain the temperature of the greenhouse. When the temperature is too low or too high, the heating valve will be automatically opened or closed.

As an emerging class of functional materials, many new uses of memory alloys are constantly being developed. For example, if a spectacle frame made of memory alloy is accidentally bent, just put it in hot water. Medium heating will restore it to its original state. In the near future, car shells may also be made of memory alloys. If it gets damaged accidentally, you can restore it to its original shape by heating it with a hair dryer, which saves money and effort, and is very convenient. SMA Solar Technology AG Company Profile

SMA Solar Technology AG is the world's leading professional inverter manufacturer and supplier. It was founded in 1981 and is headquartered in Niestetal, Kassel, Germany.

SMA is the global market leader in photovoltaic inverters. Its products are used all over the world and have been installed in 13 countries on four continents, including the United States, China, Italy, Spain, France, Australia, Greece, Branches have been set up in the Czech Republic. After 29 years of innovative development, SMA currently has more than 4,000 employees. In 2009, it built the world's largest photovoltaic inverter production base covering an area of ??18,500 square meters, which can increase SMA's annual production capacity. to approximately 5GW and continuing to expand, which can meet the needs of the rapid development of the global photovoltaic market. On June 27, 2008, SMA was listed on the Frankfurt Stock Exchange in Germany (s92), and was listed on TecSMA on September 22, 2008. In the past few years, the SMA company itself, as well as the many products it innovatively produces, Created more achievements and won many awards.

Main Products

SMA’s main business area is the development and production of various models of photovoltaic inverters, with powers ranging from 1kW to 1.25MW,

It can meet the needs of different types of photovoltaic modules, all power plant sizes and different grid types.

The photovoltaic series equipment developed and produced by SMA mainly include grid-connected inverters Sunny Boy/Sunny Mini Central/SunnyTripower/Sunny Central, bidirectional independent operation inverter Sunny Island, wind power grid-connected inverter WindyBoy, Grid-connected backup power generation equipment Sunny Backup, fuel cell inverter Hydro Boy, and communication equipment for comprehensive monitoring and control of the power station. Among them, photovoltaic grid-connected and two-way independent operating inverters are its main products. SMA has launched nearly 100 photovoltaic inverter series related products, making it truly the world's largest manufacturer and supplier of photovoltaic inverters.

Innovative Technology

Since its inception, SMA has taken innovative technology as the main goal of corporate development, and has continuously sought more reasonable solutions for future photovoltaic products. SMA has more than 400 R&D personnel and a R&D budget of more than 80 million euros in 2010. The string inverter technology developed and produced by SMA in 1995 was a great success in reducing cost and price of photovoltaic grid-connected system technology, which greatly simplified the design and installation of photovoltaic power station systems; since then, SMA's advanced photovoltaic technology has been leading the photovoltaic field With the development of technology, many innovative technologies, such as OptiCool, H5 and HE technology, have improved the conversion efficiency of equipment; the application of multi-string monitoring technology, ESS and Bluetooth technology has not only greatly reduced the cost of inverters, but also created a number of New standards in photovoltaic technology.

Market situation

SMA is a professional inverter manufacturer and plays an important role in the global photovoltaic market.

It has a development history of 29 years, has a good reputation for its leading technology and stable and reliable product quality, and has a good reputation in the photovoltaic market. By the end of 2009, SMA's global installed capacity had exceeded 9.1GWp, and AC installed capacity in 2009 alone reached 3.4GWp. SMA not only has a high market share in Germany, but has also been very successful in developing overseas markets. Its products are used all over the world, and it has set up branches in 13 countries on four continents around the world, providing more convenient services for global users to use SMA equipment. channel. In recent years, SMA has maintained a growth rate of more than 100% and will continue to maintain strong growth in the next few years.

Production Capacity

SMA is a professional inverter manufacturer that has obtained DIN EN ISO 9001:2000 production management system certification. The product production process has strict organizational management. The complete management system includes safety guarantee system, document management system, production process safeguard measures, equipment testing system and supporting logistics, etc., which provides a strong guarantee for efficient production and reliable quality of equipment. In order to meet more demands from the development of the global photovoltaic market, SMA invested approximately 50 million euros and built the world's largest photovoltaic inverter production base covering an area of ??18,500 square meters in 2009, with an annual output of approximately 5GW. The new production base uses solar energy to provide all required energy, achieving zero carbon dioxide emissions. SMA will continue to expand production capacity and is expected to achieve a factory expansion with an annual output of 11GW in the first half of 2010. SMA's overseas factories in the United States and Canada are about to start production. Simple Moving Average (SMA)

The arithmetic moving average is a simple and common moving average. The average line refers to the arithmetic mean, calculated by adding a group of numbers and dividing by the number of components of the group of data, where each given time limit has equal weight in calculating the average. Taking the 5-day moving average as an example, the formula is as follows:

MA=(C1+C2+C3+C4+C5)/5

General formula: MA=(C1+C2 +C3+C4+C5+....+Cn)/n

C: Closing price of the first day

n: Moving average period

In In the term "moving average", "moving" means that when we calculate a new average, we usually subtract the earliest price data from the previous moving average, and then add the latest price data to this numerically. In this way, as new data is continuously added, the average value will move forward.

From the above example of a simple moving average, we can see that the gold price of each day accounts for 1/5 of the total moving average (because this is the average of the 5-day moving average example). In a 9-day moving average, each day's price accounts for only 1/9 of the total moving average. It can be seen that the larger the time parameter of the moving average, the smaller the impact of individual price data on the average.

The shorter the time parameter of the moving average, the closer the moving average is to the price chart. This type of average is more sensitive to current price changes. In this sense, this is an advantage. It also has a negative side, that is, the possibility of triggering a "see-saw phenomenon" has also increased. Long-term moving averages provide a strong smoothing effect, but they are slow to current price changes.

Among the more popular moving averages, for short-term traders, they include 4-day, 9-day, and 18-day moving averages; for market participants operating long-term positions, they include 13-day moving averages. weekly, 26-week, and 40-week moving averages. In Japan, 13-week and 40-week moving averages are most commonly used. Moving averages are used by a wide range of market participants, including day traders and hedge traders. The former applies the moving average method to real-time trading data, while the moving average in the latter's eyes may be calculated on a monthly or even annual basis.

In the moving average research method, in addition to selecting different time parameters, it is also possible to select different price data to calculate the average. As we introduced in the previous example, the vast majority of moving average systems use closing prices for their calculations. However, there are also many people who use the highest price, the lowest price, and the middle price between the highest price and the lowest price to calculate the moving average. Sometimes, people even use moving averages. Methanogenic Activity (Specific Methanogenic Activity)

The term anaerobic process in water pollution control engineering refers to the maximum rate of methane production per unit mass of anaerobic sludge under certain conditions. The units are milliliters of methane/(grams of volatile suspended solids*day), cubic meters of methane/(kilograms of volatile suspended solids*day) Selective Modal Analysis (SELECTIVE MODAL ANALYSIS)

Modal analysis is A modern method to study the dynamic characteristics of structures is the application of system identification methods in the field of engineering vibration. Mode is the natural vibration characteristic of the mechanical structure. Each mode has a specific natural frequency, damping ratio and mode shape. These modal parameters can be obtained by calculation or experimental analysis. Such a calculation or experimental analysis process is called modal analysis.

If this analysis process is obtained by finite element calculation, it is called computational modal analysis; if the modal parameters are obtained through parameter identification of the collected system input and output signals through experiments, it is called experimental modal analysis. Usually, modal analysis refers to experimental modal analysis.

12. Super Mario Advance, a GBA game released by Nintendo

Super Mario A (Super Mario Advance) is a game released by Nintendo on the GBA in 2001, roughly NES A remaster of Super Mario Bros. 2, which adds a challenge mode to collect Yoshi eggs and NES Mario Bros. A package form of chip diodes, also called DO-214AC. Similar packages include SMB (DO-214AA), SMC (DO-214AB) and other packages. The difference between them lies in the size of the device: SMA