Virtual currency training in Beijing
if you are interested in cryptocurrency, it is recommended to play with some well-known, open and transparent currencies with strong operators. For example, bitcoin, Leyte, Dijing and dogcoin. Dijing is a leader in the new generation of token. It has some innovation and focuses on the coin business circle, but there are still risks.
2. Stops: old market, Xiaoma crossing, Kehua crossing, Qianqing, Yaqian, Yangxunqiao crossing, huamucheng, Binjiang campus, hupaolu zoo, yanggongdi, Shuguang Road, Huanglong tourism distribution center
Third, put the vehicle into operation. In the first phase, 10 high-end air-conditioned vehicles were put into use in Shaoxing County and Hangzhou
you can also take a bus from Keqiao to Hangzhou east bus station, and then take bus 317 to Binjiang
while China is striving to narrow the gap with the world's naval power, Japan, a former naval power and China's neighbor, has built a strong 88 fleet as early as the 1980s to meet its demand for "1000 nautical miles ocean escort". Based on five general purpose destroyers, two air defense destroyers and one helicopter destroyer, this fleet has strong comprehensive combat capability. With the development of the times, Japan's newly-built "King Kong" class and "aitao" class air defense destroyers and "Gaobo" class destroyers have been serving in the sea one after another, and Japan's sea has formed a more sophisticated 90 fleet accordingly[ Overall layout and stealth capability first of all, 054A stealth frigate: Based on the data provided by all parties, it is assumed that the data should be 3600 tons of standard displacement and 4000 tons of full load displacement (there is also a saying that 3900 tons of target displacement and 4500 tons of full load displacement). The ship is 134m long, 16m wide, 5m draught, and the aspect ratio is close to 8.6. Maximum speed 27 knots, 18 knots, enrance 3800 nautical miles, 190 crew
in terms of overall situation, since the Chinese Navy had a lot of exchanges with the European navies in the 1980s, especially the French, Italian and British navies, and was deeply influenced by their design, when Jiangwei class frigates appeared, they inadvertently revealed some traces of the design of Western ships, When the 054 frigate appeared, it obviously borrowed some of the body designs of some French "Lafayette" frigates: popular flying shear bow, freeboard high and floating out, square stern linear structure, and small aspect ratio. Its bow is high (the height is similar to that of Russian 956 "modern" class destroyer) and its transverse section is deep V-shaped, which can well prevent buffeting and waves. Its excellent hull line shape, relatively small aspect ratio and reasonable use of fin stabilizer can ensure its seakeeping to meet the needs of ocean navigation, which has been confirmed by the second and third batch of naval escort operations to the Persian Gulf
in terms of stealth design, the effect of Lafite class is also obvious, with freeboard camber of 10 °~ twenty °, Superstructure sidewall inclination 7 °~ fifteen °, Both of them are combined into an organic whole by the corner line which is almost used to pass through the whole ship. By making its cross section present a rhombic structure, the direction of the radar radiation wave can be changed, the scattering space can be reced, the echo intensity can be reced, and the radar reflection cross section can be reced. At the same time, the corner line starts from the back part of the wall of the ship's bow side, which is strongly floating, and passes through the shielding net outside the space of the lifeboat on the side side of the midship, which is flush with the helicopter platform. Its purpose is to cover the chain winch, cable pile, windlass and other equipment on the bow deck which is not concive to radar stealth, and the design idea of deliberately recing the target signal characteristics runs through the design. In addition, radar absorbing coating is used to further improve radar stealth performance. In terms of acoustic stealth treatment, diesel engines and generators use double-layer raft devices to rece vibration and noise, and the use of new low-noise 5 large side slope low-speed propeller also strengthens this purpose. In the infrared stealth processing, its huge chimney shows that it has spray cooling facilities to suppress infrared radiation
let's look at the "high wave" class: 151 meters in length, 17.4 meters in width and 5.3 meters in draft. The standard displacement is 4650 tons, and the full load displacement is 5500 tons. The ratio of length to width is 8.88, the maximum speed is 30 knots, carrying 175 people. In addition, the layout of engine room is similar. The differences are mainly reflected in the bridge, helicopter hangar and chimney. The ship has excellent ocean navigation quality to ensure that it can normally use oqr-2 low-frequency towed sonar to carry out anti submarine operation in bad sea conditions
in the stealth design, the "high wave" class also uses two methods: shape modification and absorbing coating (such as the use on the mast) to achieve the goal of weakening the radar reflection. Its hull is 8 ° The cross section is V-shaped e to the outward inclination of the cross section; The superstructure should be designed to eliminate the radar reflection as much as possible; In terms of infrared and noise stealth, relevant infrared suppression devices, shock absorbing floating rafts, low-noise and highly skewed propellers, and aerosol noise rection systems are also adopted to improve the comprehensive stealth capability. The overall stealth effect has reached the world advanced level[ Power system in power system: 054A is also influenced by Lafite class, and adopts CODAD power propulsion mode, which is composed of four pilstek 16pa6v280stc diesel engines proced by Shaanxi Diesel according to the license, with a single maximum power of 6400kw and a total power rate of 25600kw. Two new 5-blade adjustable pitch and large pitch low speed propellers are driven by two shafts. The design of the air intake in the lower front of the chimney is similar to Burke's style. The large size of the chimney indicates that it has a spray cooling facility to suppress the infrared radiation. In addition, there are two mtu-396 diesel generator sets with power of 1500kW, reaching the same level as "high wave". Don't underestimate this change. One of the reasons why the modernization of Chinese Navy destroyers and frigates was very small in the past was that the power of the power station was very small (400KW), which could only meet the power supply demand of the electromechanical, electronic and weapon equipment on board when they were newly built. The reserve power could not meet the needs of the newly improved equipment on board. As a result, the modernization was only related to communication and communication In the field of electronic warfare and other systems
many people have different opinions on the use of CODAD power mode for 054A. In fact, the power mode of CODAD first appeared on the French Navy's Casar class air defense missile destroyer. Its four high-power pierstick 18pa6v280btc diesel engines can output 31752kw of total power, so that the 5000 ton Casar can reach 29.5 knots. It was a good area air defense ship for fuhee and later Charles de Gaulle (CVN). Later, the Lafite class adopted the CODAD power unit composed of four 16pa6v280stc diesel engines. In fact, Lafite class still exists in the formation of French aircraft carriers. Considering that the output of domestic gas turbine can not meet the Navy's needs at present, the first thing is to ensure the demand of domestic large ocean destroyer. At the same time, the technical support department of the Chinese navy has rich experience and complete technical means for long-term maintenance of such power plants. Therefore, it is the most appropriate project to use advanced and mature high-power medium and high-speed diesel engine as the main power device of medium-sized warship
rihai has fully implemented COGAG since it was on the "Chaowu" class general destroyer. At that time, it was referring to the model of dd-963 class of the United States. Considering that its full capacity is less than 4200 tons, which is almost half of the latter, rihai chose four "Spey" SMIA gas turbines from the traditional supplier R.R., with a total power of 39100kw. It can solve the contradiction between the quiet environment of high-speed pursuit of nuclear submarine and low-speed towed linear array sonar. When the new "village rain" class was built later, because the full discharge increased to 5100 tons, more power was needed to ensure that the speed could reach 30 knots. Therefore, two of the main engines were replaced by lm2500 with higher power, in order to keep the original characteristics in the case of increased displacement. The "high wave" class basically "copies" such a mode: four main engines are installed in two power cabins respectively, and the general layout of front and rear port and starboard is adopted. The first engine room is arranged on the front port side, with No.1 and No.2 engines built in to drive the left propulsion shaft. The second engine room is arranged on the starboard side of the rear, with No. 3 and No. 4 engines built in to drive the right propulsion shaft. 1. Unit 4 is lm2500 proced by GE; 2. Unit 3 is sm1c proced by R.R. The advantages of this arrangement are: first, it improves the anti damage ability of the aircraft; second, as a cruiser, sm1c has lower fuel consumption and noise than lm2500; its navigation quietness and enrance are better than "Chaowu"; third, the total power is 44400kw when the vehicle is combined to ensure that the maximum speed is 30 knots, meeting the needs of pursuing submarines[ [editor's note] the antisubmarine capability is the same as that of the "high wave" class. In the general layout and power plant selection, the 054A attaches great importance to the quiet environment required for the low speed towed linear array sonar's submarine search time outline, and the corresponding development work is carried out, and the goal is basically achieved through various efforts. The common equipment and use of ball bow active intermediate frequency sonar and towed linear array towed sonar can search and lock nuclear submarines and quiet diesel electric submarines. At the same time, the imported Ka-28 antisubmarine helicopter has a complete set of relatively perfect antisubmarine detection equipment. It is equipped with a small sea search radar under the nose. In addition to detecting sea targets, it can also detect submarines in the ventilation tube state. There is a special ordnance cabin under the fuselage, a vgs-3 active low frequency suspended sonar, and a magnetic detector at the rear of the fuselage
in addition, as early as the 054 basic model, the Chinese Navy for the first time has a complete and systematic anti submarine equipment on the frigate. In a sense, it has basically reached or approached the level comparable to the "high wave" class. By the end of 054A, it has realized the rocket assisted torpedo with hot vertical firing, and has the potential to become a professional anti submarine ship. It is similar to the Ka-28 anti submarine helicopter (which can carry the former Soviet Union's anti submarine helicopter specially designed to deal with us made nuclear submarines) АПР-ЗЭ Air anti submarine torpedo, Yu-7 324mm light anti submarine torpedo and 3200 6-Tube rocket deep bomb launcher constitute three anti submarine fire strike networks in the far, middle and near,
the design basis of 054 frigate may come from the f-16u frigate previously used for export. Compared with the previous domestic Jiangwei class frigates, the 054 frigate is more concise and avant-garde in appearance, completely getting rid of the impression that the superstructure of Jianghu class and Jiangwei class frigates is scattered and low. Compared with the Chinese Navy's new 052B / C missile destroyer, the new 054 frigate has a more concise outline. It adopts a stepped superstructure integrated with the ship's side. The bridge, tower shaped front mast and composite rear mast / chimney structure are all inclined (and the inclined angle is generally quite obvious), avoiding acute angle and complex structure, Some equipment on the surface of the warship, such as boat crane, is also covered by bulwarks, which makes the stealth design of 054 frigate close to the advanced level of the West. The displacement and hull of 054 frigate is much larger than that of Jiangwei class II frigate with a displacement of 2250 tons. It has better ocean navigation ability and can accompany the ocean fleet. However, after the first two warships of 054 frigate were built and launched, it can be inferred that 054 frigate is still a kind of transitional warship from the eight joint haihongqi 7 air defense missile launcher. Starting from the third ship, the second batch of 054 frigates have made many significant improvements in design and equipment, among which the biggest improvement is the addition of domestic vertical air defense missile launcher, which greatly strengthens the air defense capability of this type of frigates. The improved 054 frigate is the present 054A stealth frigate. 054A stealth frigate is also a new type of surface combat ship equipped by the Chinese Navy, and a few of them can build more than two, which shows that its design has become mature. With the improvement of comprehensive operational performance and low cost, 054A frigate graally plays the role of general destroyer in Chinese fleet
while China is striving to narrow the gap with the world's naval power, Japan, a former naval power and China's neighbor, has built a strong 88 fleet as early as the 1980s to meet its demand for "1000 nautical miles ocean escort". Based on five general purpose destroyers, two air defense destroyers and one helicopter destroyer, this fleet has strong comprehensive combat capability. With the development of the times, Japan's newly-built "King Kong" class and "aitao" class air defense destroyers and "Gaobo" class destroyers have been serving in the sea one after another, and Japan's sea has formed a more sophisticated 90 fleet accordingly. Overall layout and stealth capability first of all, 054A stealth frigate: Based on the data provided by all parties, it is assumed that the data should be 3600 tons of standard displacement and 4000 tons of full load displacement (there is also a saying that the index row is 3900 tons and 4500 tons of full load displacement). The ship is 134m long, 16m wide, 5m draught, and the aspect ratio is close to 8.6. Maximum speed 27 knots, 18 knots, enrance 3800 nautical miles, 190 crew
in terms of overall situation, since the Chinese Navy had a lot of exchanges with the European navies in the 1980s, especially the French, Italian and British navies, and was deeply influenced by their design, when Jiangwei class frigates appeared, they inadvertently revealed some traces of the design of Western ships, When the 054 frigate appeared, it obviously borrowed some of the body designs of some French "Lafayette" frigates: popular flying shear bow, freeboard high and floating out, square stern linear structure, and small aspect ratio. Its bow is high (the height is similar to that of Russian 956 "modern" class destroyer) and its transverse section is deep V-shaped, which can well prevent buffeting and waves. Its excellent hull line shape, relatively small aspect ratio and reasonable use of fin stabilizer can ensure its seakeeping to meet the needs of ocean navigation, which has been confirmed by the second and third batch of naval escort operations to the Persian Gulf
in terms of stealth design, the effect of Lafite class is also obvious, with freeboard camber of 10 °~ twenty °, Superstructure sidewall inclination 7 °~ fifteen °, Both of them are combined into an organic whole by the corner line which is almost used to pass through the whole ship. By making its cross section present a rhombic structure, the direction of the radar radiation wave can be changed, the scattering space can be reced, the echo intensity can be reced, and the radar reflection cross section can be reced. At the same time, the corner line starts from the back part of the wall of the ship's bow side, which is strongly floating, and passes through the shielding net outside the space of the lifeboat on the side side of the midship, which is flush with the helicopter platform. Its purpose is to cover the chain winch, cable pile, windlass and other equipment on the bow deck which is not concive to radar stealth, and the design idea of deliberately recing the target signal characteristics runs through the design. In addition, radar absorbing coating is used to further improve radar stealth performance. In terms of acoustic stealth treatment, diesel engines and generators use double-layer raft devices to rece vibration and noise, and the use of new low-noise 5 large side slope low-speed propeller also strengthens this purpose. In the infrared stealth processing, its huge chimney shows that it has spray cooling facilities to suppress infrared radiation
let's look at the "high wave" class: 151 meters in length, 17.4 meters in width and 5.3 meters in draft. The standard displacement is 4650 tons, and the full load displacement is 5500 tons. The ratio of length to width is 8.88, the maximum speed is 30 knots, carrying 175 people. In addition, the layout of engine room is similar. The differences are mainly reflected in the bridge, helicopter hangar and chimney. The ship has excellent ocean navigation quality to ensure that it can normally use oqr-2 low-frequency towed sonar to carry out anti submarine operation in bad sea conditions
in the stealth design, the "high wave" class also uses two methods: shape modification and absorbing coating (such as the use on the mast) to achieve the goal of weakening the radar reflection. Its hull is 8 ° The cross section is V-shaped e to the outward inclination of the cross section; The superstructure should be designed to eliminate the radar reflection as much as possible; In terms of infrared and noise stealth, relevant infrared suppression devices, shock absorbing floating rafts, low-noise and highly skewed propellers, and aerosol noise rection systems are also adopted to improve the comprehensive stealth capability. The overall stealth effect has reached the world advanced level. Power system in the power system: 054A is also affected by Lafite class and adopts the CODAD power propulsion mode, which is composed of four pilstek 16pa6v280stc diesel engines proced by Shaanxi Diesel according to the license, with the maximum power of 6400kw and the total power of 25600kw. Two new 5-blade adjustable pitch and large pitch low speed propellers are driven by two shafts. The design of the air intake in the lower front of the chimney is similar to Burke's style. The large size of the chimney indicates that it has a spray cooling facility to suppress the infrared radiation. In addition, there are two mtu-396 diesel generator sets with power of 1500kW, reaching the same level as "high wave". Don't underestimate this change. One of the reasons why the modernization of Chinese Navy destroyers and frigates was very small in the past was that the power of the power station was very small (400KW), which could only meet the power supply demand of the electromechanical, electronic and weapon equipment on board when they were newly built. The reserve power could not meet the needs of the newly improved equipment on board. As a result, the modernization was only related to communication and communication In the field of electronic warfare and other systems
many people have different opinions on the use of CODAD power mode for 054A. In fact, the power mode of CODAD first appeared on the French Navy's Casar class air defense missile destroyer. Its four high-power pierstick 18pa6v280btc diesel engines can output 31752kw of total power, so that the 5000 ton Casar can reach 29.5 knots. It was a good area air defense ship for fuhee and later Charles de Gaulle (CVN). Later, the Lafite class adopted the CODAD power unit composed of four 16pa6v280stc diesel engines. In fact, Lafite class still exists in the formation of French aircraft carriers. Considering that the output of domestic gas turbine can not meet the Navy's needs at present, the first thing is to ensure the demand of domestic large ocean destroyer. At the same time, the technical support department of the Chinese navy has rich experience and complete technical means for long-term maintenance of such power plants. Therefore, it is the most appropriate project to use advanced and mature high-power medium and high-speed diesel engine as the main power device of medium-sized warship
rihai has fully implemented COGAG since it was on the "Chaowu" class general destroyer. At that time, it was referring to the model of dd-963 class of the United States. Considering that its full capacity is less than 4200 tons, which is almost half of the latter, rihai chose four "Spey" SMIA gas turbines from the traditional supplier R.R., with a total power of 39100kw. It can solve the contradiction between the quiet environment of high-speed pursuit of nuclear submarine and low-speed towed linear array sonar. When the new "village rain" class was built later, because the full discharge increased to 5100 tons, more power was needed to ensure that the speed could reach 30 knots. Therefore, two of the main engines were replaced by lm2500 with higher power, in order to keep the original characteristics in the case of increased displacement. The "high wave" class basically "copies" such a mode: four main engines are installed in two power cabins respectively, and the general layout of front and rear port and starboard is adopted. The first engine room is arranged on the front port side, with No.1 and No.2 engines built in to drive the left propulsion shaft. The second engine room is arranged on the starboard side of the rear, with No. 3 and No. 4 engines built in to drive the right propulsion shaft. 1. Unit 4 is lm2500 proced by GE; 2. Unit 3 is sm1c proced by R.R. The advantages of this arrangement are: first, it improves the anti damage ability of the aircraft; second, as a cruiser, sm1c has lower fuel consumption and noise than lm2500; its navigation quietness and enrance are better than "Chaowu"; third, the total power is 44400kw when the vehicle is combined to ensure that the maximum speed is 30 knots, meeting the needs of pursuing submarines. The antisubmarine capability is the same as the "high wave" class. In the general layout and power plant selection, model 054A attaches great importance to the quiet environment required for the low speed towed linear array sonar's submarine search time outline, and the corresponding development work has been carried out, and the purpose has been basically achieved through various efforts. The common equipment and use of the ball bow active intermediate frequency sonar and towed linear array towed sonar can search and lock easily
it is different from the virtual currency in the virtual world, because it can be used for real goods and services transactions, not limited to online games. The early digital currency (digital gold currency) is a form of electronic currency named after the weight of gold. Today's digital currency, such as bitcoin, lightcoin and ppcoin, is an electronic currency created, issued and circulated by check sum cryptography. It is characterized by the use of P2P peer-to-peer network technology to issue, manage and circulate currency. In theory, it avoids bureaucratic examination and approval, so that everyone has the right to issue currency
digital currency has done a good job, so we can send it to the chain for training.
1) efficient and scalable performance
borderless system realizes over 100000 times / s batch transfer
high performance blockchain technology is necessary for cryptocurrency and smart contract platform, and can provide a solution that may replace the existing financial platform for the instry. In order to be able to process more transactions per second than visa and MasterCard, unbounded redesign starts from the bottom. Through the share authorization mechanism, the unbounded network can confirm more than 100000 transfer transactions in an average of one second
overview of borderless system architecture. The Lmax can process up to 6 million transactions per second. The key point of unbounded learning from its technology, As follows:
A) put everything in memory
b) put the core business logic in a single thread
C) put the encryption algorithm operation (hash and signature) outside the core business logic
d) divide the verification operation into state independent and state dependent checking
e) use an object-oriented data model
by following these simple rules, Unbounded can process 100000 transfers per second without disruptive optimization. If there is further optimization work, unbounded can achieve the performance similar to that of Lmax exchange (i.e. 6 million times per second). It should be noted that unbounded performance is highly dependent on one of the compatible transaction protocols. If you want to use business logic to run on a virtual machine that operates encryption algorithm and calls all objects with hash identifier, it is impossible to achieve the same level of performance. Blockchain is inherently single threaded, and the performance of single core CPU is one of the most scarce and difficult to expand. Unbounded technical logic can make the single thread execution highly efficient
endorsement of core business of borderless system
blockchain is a global account book that determines to modify a shared global state transaction. The orders contained in these transactions can change the validity of other transactions. For example, you cannot withdraw money from your bank account before the deposit of your check takes effect. You can't know if a transaction is valid until all previous transactions that can affect a particular account are processed. If two unrelated accounts do not share any common dependency, theoretically, the transactions between the two accounts can be processed at the same time. In fact, it's tricky to identify which transactions are truly independent on a smart contract driven ledger with arbitration conditions. The only way to ensure that the two transactions are truly independent is by maintaining a completely separate ledger and then transferring value between them on a regular basis. If we want to use this kind of performance tradeoff to compare, it can be like the relationship between non-uniform memory access (NUMA) and uniform memory access (UMA). In fact, the consistent memory access architecture is easier for developers to design, and the cost is lower. Inconsistent memory access architecture is usually used as a last resort when building supercomputers and large computer clusters. The computer instry has graally realized that it is not as easy to achieve performance expansion through parallel computing as it was in the early days. After all, the most important thing to do at that time was to increase the frequency of the processor. It is for this reason that processor designers are trying to improve the performance of single thread before trying to use multi thread settings. When multithreading is not enough, and only in this way, cluster computing will be considered
many people in the cryptocurrency instry try to solve the problem of scalability by cluster computing before exploring what can be achieved by a single core of a computer technically
2) Lmax disruptor decomposer technology
Lmax decomposer provides a learning example of what can be achieved on a single thread. Lmax is a trading platform for end customers with the goal of becoming the fastest exchange in the world. They have been very generous in publishing what they have learned<
overview of Lmax architecture:
business logic processor is where all sequential transactions and order matching occur. It is a single thread that can process millions of orders per second. This architecture can be easily used in the field of cryptocurrency and blockchain design. The role of the input resolver is to collect orders from many users from different sources and assign them to a certain order. When the order is assigned to them, they are copied, recorded and broadcast to many rendant business logic processors. The input resolver is highly parallel and can be easily sub contracted into a computer cluster system. When the business logic processor has finished processing the input, an output resolver is responsible for informing those who care about the result. This is also a highly parallel task. Finally, by using a single threaded sample processor and Java virtual machine in the business logic processor, Lmax can execute 6 million transactions per second. If Lmax can achieve this goal, then cryptocurrency and smart contract platform do not need to consider the cluster network solution under the condition of less than 10 transactions per second. High performance blockchain
to build a high-performance blockchain, we need to use the same technology as Lmax. Here are a few things that must be done: put everything in memory, avoid synchronization primitives (locking, atomic operations), and avoid unnecessary calculations on business logic processors. Because memory is designed to be highly parallel, it's getting cheaper. The amount of data needed to track everyone's account balance and permissions on the Internet can be stored in less than 1TB of ram, which can be purchased for less than $15000, and can be installed on the commercialized (high-end) server motherboard. Before the system was adopted by 3 billion people, this kind of hardware would be seen in ordinary desktop computers. The real bottleneck is not the demand of memory capacity, but the demand of bandwidth. In the case of 1 million transactions per second and 256 bytes per transaction, the network will need 256MB of data per second, that is, 1GBIT / s bandwidth. Such bandwidth is not common on ordinary desktop computers. However, such bandwidth is only a little bit of the 100Gbit / s bandwidth of the second generation Internet. The second-generation Internet is available to more than 210 U.S. ecational institutions, 70 companies and 45 non-profit and government agencies
in other words, blockchain technology can easily keep everything in memory, and if properly designed, it can be extended to support millions of transfers per second
3) allocate ID and avoid hash calculation
in a single threaded system, processor cycle is a scarce resource that needs to be reserved. Traditional blockchain design uses hash calculation based on encryption algorithm to generate a unique global ID system, so as to ensure that there will be no collision statistically. The problem with these hashes is that they consume more and more memory and processor cycles. Compared with a direct array index, this method will significantly take up more processor time to find the records of an account. For example, 64 bit integers are easier to compare and operate than 160 bit IDs. A larger hash ID mechanism means less space in the CPU cache and more memory is needed. In the modern operating system, the ram which is not often accessed will be compressed, but the hash identifier is a random number, which cannot be compressed. The model blockchain gives us a way to assign unique IDs around the world. These IDS will not conflict with each other. Therefore, it completely avoids using the identifier based on hash algorithm like bitcoin address to refer to an account, balance or license
4) remove signature verification from the business logic processor
all transactions in the cryptocurrency network depend on the use of encryption algorithm signature to verify permissions. In most cases, the requested permissions can be changed by the results of other transactions. This means that in the business logic processor, permissions need to be defined as a case that has nothing to do with the calculation of encryption algorithm
to achieve this goal, all public keys need to be assigned a unique and irreplaceable ID. After the ID is assigned, the input resolver can verify whether the provided signature matches the specified ID. When the transaction arrives at the business logic processor, you just need to check the ID
the same technology can remove prerequisite checking on objects with irreplaceable static IDs
5) designing transactions for static verification
for transactions, there are many features that can be statically checked without referring to the current global state. These checks include parameter range checking, input de rendancy and array sorting. In general, there are a lot of checks that can be done if the transaction contains data that it "assumes" is global. After these checks are executed, the business logic processor has to make sure that these assumptions are correct. The process is to check the modification timestamp of an object reference related to the transaction signature time
6) smart contract
many blockchains are integrating a common scripting language to define all operations. These designs ultimately define the business logic processor as a virtual machine, and all transactions are defined as scripts run by the virtual machine. This solution has a single threaded performance limit on a real processor, and the problem is exacerbated by forcing everything to be executed through a virtual processor. A virtual processor will always be slower than a real processor even if it uses JIT, but the computing speed is not the only problem of this "everything is a script" scheme. When the transaction is defined at such a low level, it means that the static check and encryption algorithm operation will still be included in the business logic processing, which will also rece the overall throughput. A script engine should never ask to perform a signature checking request for an encryption algorithm, even if the request is implemented through a native mechanism
according to the course we learned from Lmax, we know that a virtual machine designed for blockchain should consider single thread performance. This means that compiler optimization should be implemented at the beginning, and the most commonly used smart contracts should be natively supported by blockchain, while only those rarely used and customized contracts will run on a virtual machine. These custom contracts are designed with performance in mind, which means that the virtual machine should limit the range of memory that can be accessed to a level that can be placed on the processor cache
7) object oriented data schema
in memory
the current price drop of virtual currency means that some people take advantage of the good news to push the market up, and then take the opportunity to ship , if large customers ship , the market price drops directly , if several large customers ship at the same time, then a big drop will be formed
in addition to the launch of bitcoin futures, the launch of futures itself is for short selling. With more short sellers, the market is very tight. It can also cause a big drop
another is that the price of bitcoin in the whole market follows the trend of bitcoin, and there are very few specific independent trends, such as Ethereum and Boca. Even if there is a period of independent trend, it will be similar to bitcoin trend in some periods
the collapse of digital currency requires large enterprises and institutions to master the delivery rhythm. If the delivery rhythm is not well mastered, it will also cause panic selling. Instead, there will be no better delivery and the market will be smashed
of course, there were examples before. When a project party was working on a project, it went online. Because too many tokens were sent to a large number of users in the early stage, and then they pulled the order by themselves. As a result, they spent a lot of money to pull the order. It was very difficult to pull the order. Finally, they put themselves in. The users were constantly selling, and the project party took the order
cryptocurrency goes down
on the evening of May 19, Beijing time, the European and American stock markets are extremely unstable. The European Stoxx 50 index once fell by 2%, while the U.S. stock market index fell sharply in the early part of the day, and the panic index rose by 15%. After the opening, the three major U.S. stock indexes accelerated their decline, with a decline of about 1.5% as of 22:17
at the same time, the international oil price also showed a sharp drop, with the price of Buyou once falling by more than 2%, and WTI crude oil futures once fell by more than 4% in the day, reaching a new low below US $62.80/barrel since April 27. Judging from the trend of US Treasury bonds, the rise in the yield of 10-year Treasury bonds also means that Treasury bonds are falling
the biggest concern is the decline of cryptocurrency, which can be described as a bloody market. Bitcoin once collapsed by 27%, Ethereum plummeted by nearly 37%, and EOS and adacoin all fell by nearly 50%