Dat digital currency outlook

3. Bitcoin uses a number of technologies, more than one, mainly distributed P2P technology, cryptography technology and so on
it is recommended to search bitcoin white paper for more information.

4. Today is June 1, 20XX. There was a basic course of enterprise management in the morning. Due to my personal affairs, I missed 3-4 classes, and I didn't ask for leave from the teacher, which had a serious impact on the class. After the teacher's instruction, I knew where my mistake was and the seriousness of the mistake of skipping class. No matter what the reason, skipping class was wrong. The main task of students is to have a good class and study well. What's the reason for not doing their job well? Skipping classes is wrong in itself. So I should review! Therefore, with guilt and regret, I wrote this review to you to show you my deep understanding of the bad behavior of truancy and my determination never to trudge again
I remember that when we entered the school as a freshman, the school and teachers had already applied for five orders and repeatedly stressed that all students should not be absent from class. But today I'm still absent for no reason. I think it's necessary to talk about truancy. The course of the matter is like this: e to the recent irregular weather and diet, I caught a cold in the stomach and intestines. I got up in the morning with serious discomfort, some fever and diarrhea, which is very uncomfortable. So, I chose the behavior of truancy. Although I know this kind of behavior is also wrong, but I still did it. Now I think this kind of behavior is very wrong. Even if I don't go, I should ask for leave. I can't be so casual. The impact is really bad, and it brings a lot of inconvenience to the class and teachers. Therefore, I think it is necessary and necessary to make this written review to the teacher, so that I can deeply reflect on my own mistakes
I'm really sorry, teacher! I committed a serious problem of principle. I know that the teacher is also very angry about my behavior of absenteeism. I also know that for students, to ensure that every class is on time, not to leave early and not to be absent from class is a basic responsibility and obligation. But I didn't even do the most basic. Afterwards, I thought calmly for a long time. I graally realized that I was going to pay for my impulse. I really deserved it. The teacher's repeated introction is still in my ears, and my serious expression is still in front of me. I am deeply shocked and have realized the importance of this. Now, the big mistake has been made, and I deeply regret it. After a deep review, I think that there are fatal mistakes in my mind: I don't have high ideological awareness, I don't have enough respect for others, I will have more respect for teachers in the future, and I don't pay enough attention to important matters. If it wasn't for being too lazy, it wouldn't be so. In order to better understand the mistakes, and also to let teachers believe that students can really correct their mistakes and ensure that they will not make them again, I sum up my mistakes as follows:
first of all, my ideological mistakes: I don't pay enough attention to the courses that I am not very interested in, and I don't pay enough attention to the courses that are not suitable for my major, That's why I don't go to this class. Of course, there are some reasons for my discomfort, but this kind of thought still has a certain impact on me. After all, I don't think I can escape the class of the department head. I didn't pay much attention to this when I began to reflect on it. However, after deep reflection, I finally realized that this mistake was the important reason for my absenteeism. Ask: if I like this course very much, if this course is our professional course, will I skip this course for no reason? This error is also reflected in the efficiency of my class which is not absent from class. Many courses I'm not interested in often I don't listen attentively from beginning to end. Although this behavior doesn't disturb the teaching and learning of my classmates and teachers, it's a serious mistake for me. For every course offered by the school, there are reasons for the school. As students, we should study hard. The serious consequences of my absenteeism are as follows:
let the teacher worry about my safety. I didn't show up on time when I should have. How can I not let the teachers who care about every student worry. And this kind of worry is likely to distract teachers from their work all day, causing more serious consequences. At the same time, it also affects the enthusiasm of teachers in class. If there are few people in class, who has the heart to teach
it has a bad influence on the students. Due to my absenteeism, this casual and inlgent attitude may cause other students to follow suit, affect the discipline of the class, and be irresponsible to the parents of other students. It's just like a stinky fish spoiling a pot of soup all the time, so this kind of influence is really bad
the most important influence on the improvement of personal comprehensive level is enterprise management. Although it's useless for the time being, it's still very effective for the improvement of comprehensive level. Who knows when it will be used, so that they can't be improved under the condition of instinctive improvement.

6. MP4 and RM are relatively small ''

ASF

ASF is the abbreviation of advanced streaming format. From the literal meaning (Advanced Streaming Format), we should see the use of this format. To put it bluntly, ASF is a file compression format developed by Microsoft in order to compete with the current real player, which can directly watch video programs on the Internet! Because it uses MPEG4 compression algorithm, so the compression rate and image quality are very good. Because ASF exists as a video "stream" format that can be watched instantly on the Internet, it is not surprising that the image quality of ASF is a little worse than VCD, but better than RAM format with the same video "stream" format. However, if you don't consider spreading on the Internet and choose the best quality to compress the files, it's no surprise that the video files generated are better than VCD (MPEG1), but in this way, ASF's original development intention will be lost, and it's better to simply use Navi or DivX. But Microsoft's "sub section" has its unique advantages, the most obvious is that all kinds of software support for it is unmatched

n avi

n avi is the abbreviation of new avi, which is a new video format developed by an underground organization named shadowrealm. It is a modification of Microsoft ASF compression algorithm (not AVI in imagination). The video format pursues nothing more than compression rate and image quality. Therefore, in order to pursue this goal, Navi improves some shortcomings of the original ASF format, so that Navi can have a higher frame rate. Of course, this is at the expense of ASF's video streaming features. To sum up, Navi is an improved ASF format without video streaming features! Another simple point is - non network version of ASF

avi

avi is the abbreviation of Audio Video Interleave. It seems that I don't need to explain more. This old video format released by Microsoft in the era of win3.1 has served us for several years. If you don't know this, I think you'd better not look down. The advantages of this thing are good compatibility, convenient calling and good image quality, but the disadvantages are also well known: large size! It is because of this that we can see from the birth of MPEG1 to the introction of MPEG4

MPEG

MPEG is the abbreviation of motion picture experts group, which includes MPEG-1, MPEG-2 and MPEG-4 (note that there is no MPEG-3, the familiar MP3 is only MPEG layeur 3). MPEG-1 is believed to be the most popular one, because it is widely used in the proction of VCD and some network applications of video clips downloading. It can be said that 99% of VCDs are compressed in MPEG1 format. (note that VCD 2.0 does not mean that VCD is compressed in MPEG-2). MPEG-1 compression algorithm is used, It can compress a 120 minute long movie (without video file) to about 1.2 GB. MPEG-2 is used in DVD proction (compression), and also in some HDTV (high definition television broadcasting) and some high demand video editing and processing. Using MPEG-2 compression algorithm to compress a 120 minute long movie (without video file) can be compressed to the size of 4 to 8 GB (of course, its image quality and other performance indicators MPEG-1 is not comparable). MPEG-4 is a new compression algorithm. The ASF format of this algorithm can compress a 120 minute movie (without video file) to about 300m video stream, which can be watched on the Internet. Other DivX formats can also be compressed to about 600m, but the image quality is much better than ASF< It can be said that DivX video coding technology is a new video compression format threatening DVD (some people say it is DVD killer). It is modified from Microsoft mpeg4v3 and uses MPEG4 compression algorithm. At the same time, it can also be said that it was developed to break various agreements of ASF. Using this encoding technology, which is said to be banned from the United States, MPEG4 only needs two CDROMs to compress a DVD! This means that you don't need to buy a DVD ROM to get the same video quality as it, and all you need is a CDROM! In addition, playing this kind of coding, the requirements of the machine is not high, as long as the CPU is more than 300MHz (whether you are PII, Celeron, PIII, amdk6 / 2, amdk6iii, amdathalon, cyrixx86), with 64 megabytes of memory and an 8 megabytes of video memory graphics card, you can play smoothly. This is absolutely a great technology, and the future is limitless<

QuickTime

QuickTime (MOV) is a video format created by apple. For a long time, it only exists on Apple's MAC. Later, it developed to support the windows platform, but to be fair, it is a good video coding format whether it is played locally or spread on the Internet as a video stream format. So far, it has four versions, of which the compression ratio of 4.0 is the best

real video

Real Video (RA, RAM) format is positioned from the beginning, which is in the application of video streaming, which can be said to be the originator of video streaming technology. It can be used in 56K modem dial-up Internet conditions to achieve uninterrupted video playback, of course, its image quality and MPEG2, DivX and other than it is not flattering. After all, to achieve uninterrupted video transmission on the Internet requires a lot of bandwidth, which is a strong competitor of ASF
what is the RMVB format
the so-called RMVB format is an extension of the RM movie format of streaming media. VB, or VBR, is the abbreviation of variable bit rate. When we play the common RM format movies in the past, we can see the word 225kbps in the lower left corner of the player, which is the bit rate. The requirement of compressed sampling rate is different between the still picture and the moving picture. If the bit rate is always fixed, the quality of the movie will be wasted

and RMVB breaks the original RM format that the average compression sampling method, on the basis of ensuring the average compression ratio, set the maximum sampling rate value which is generally twice the average sampling rate. High bit rate is used for complex dynamic pictures (song and dance, flying car, war, etc.), while in static pictures, it is flexibly converted to low sampling rate, which makes rational use of bit rate resources, so that RMVB can maximally compress the size of the movie at the expense of a small amount of movie quality that you can't detect, and finally has a nearly perfect audio-visual effect close to DVD quality, As shown in Figure 1 is the RMVB format of the "Saint fighter of the underworld chapter.". It can be said that the volume and clarity are "fish and bear's paw", and its development prospect can not be underestimated

compared with DVDRip, the advantage of rmvb is self-evident. First of all, on the premise of ensuring the overall audio-visual effect of the film, the size of rmvb is only about 300 ~ 450MB (based on the standard film of 90 minutes), while DVDRip needs 700MB or more; Secondly, the subtitle of rmvb is embedded subtitle, unlike the installation and debugging of subtitle plug-in software of DVDRip, sometimes there will be garbled code; What's more, RMVB video player only needs to install the decoder at one time, and there is no need to debug the video or sound effects in the future. However, there are a lot of video and audio decoders in DVDRip, and improper setting will cause problems such as out of sync of audio and picture, losing sound on the screen and so on< Avi format: its full English name is audio video
interleaved, that is, Audio Video Interleaved format. It was launched by Microsoft in 1992, and is known and known by people together with windows 3.1. The so-called "audio video interleaving" means that video and audio can be interleaved together for synchronous playback. The advantage of this video format is that it has good image quality and can be used across multiple platforms. Its disadvantage is that the volume is too large. What's worse is that the compression standards are not unified. The most common phenomenon is that the high version of Windows media player can't play the video in avi format edited by early coding, However, the lower version of Windows media player can't play the video in avi format edited by the latest coding, so when we play some video in avi format, we often have some puzzling problems, such as the video can't be played or even if it can be played, we can't adjust the playing progress and only have sound without image, If users encounter these problems when playing video in avi format, they can solve them by downloading the corresponding decoder
● avi format: avi is the abbreviation of newavi, which is a new video format developed by an underground organization named shadowrealm. It is modified by the Microsoft
ASF compression algorithm, but it is different from the ASF video format in the network video described below. It greatly improves the definition of ASF video files by increasing the frame rate at the cost of sacrificing the "stream" characteristics of the original ASF video files
● dv-avi format: the full English name of DV is digital video
format, which is a home digital video format jointly proposed by Sony, Panasonic, JVC and other manufacturers. At present, this format is used to record video data by very popular digital cameras. It can transmit video data to the computer through IEEE
1394 port, and also record the edited video data back to the digital camera. The file extension of this video format is. Avi, so it is also called dv-avi format
● MPEG format: its English full name is moving picture expert
group, which is the format of moving picture expert group. VCD, SVCD and DVD that are often watched at home are such formats. MPEG file format is the international standard of moving image compression algorithm. It uses lossy compression method to rece the rendant information in moving image. To make it more clear, the compression method of MPEG is based on the fact that most of the adjacent two pictures are the same, and the rendant parts in the subsequent image and the previous image are removed, So as to achieve the purpose of compression (the maximum compression ratio can reach 200:1). At present, there are three compression standards for MPEG format, namely MPEG-1, MPEG-2 and MPEG-4. In addition, MPEG-7 and MPEG-21 are still in the research and development stage< MPEG-1: established in 1992, it is an international standard designed for the encoding of moving images and associated sound in digital storage media with data transmission rate below 1.5mbps. That is, we usually see the VCD proction format. Using MPEG-1 compression algorithm, a 120 minute long movie can be compressed to about 1.2GB. The file extensions of this video format include. Mpg,. MLV,. MPE,. MPEG and. Dat file in VCD< MPEG-2: developed in 1994, it aims to improve the image quality and transmission rate of advanced instry standard. This format is mainly used in DVD / SVCD proction (compression), at the same time in some HDTV (high definition television broadcasting) and some high demand video editing and processing. Using MPEG-2 compression algorithm, a 120 minute long movie can be compressed to 4 to 8GB. File expansion of this video format

7. Preliminary study on 99mTc-TRODAT-1 dopamine transporter imaging in human brain? Setting: Department of nuclear medicine, First Affiliated Hospital of Sun Yat Sen Medical University 510080

key words: dopamine transporter; Parkinson's disease; Single photon emission computed tomography; Radionuclide

preliminary study of? 99mTc-TRODAT-1 DAT SPECT in human brain

Hu Ping Chen Ling Zhang Haiqin Li Jinru Li Weimin Li Chunyi Wu Kening

Nuclear Medicine Department, The First Affiliated Hospital of Sun Yat-sen University of Medical Sciences. Guangzhou. 510080. Tel:

AbstractObjective To investigate the feasibility of using ? 99mTc-TRODAT-1 DAT SPECT in human brain DAT assessment, and to explore the clinical application values evaluation of ? 99mTc-TRODAT-1 DAT SPECT in Parkinson?s disease(PD). Methods Using ? 99mTc-TRODAT-1 as radiopharmaceuticals for DAT SPECT, we acquired SPECT images of normal control and of patients with PD.Results Normal human brain SPECT image were acquired 30 min after injection. The images was similar with regional cerebral flow (rCBF) image; 3～5 hours after injection, the basal ganglia (BG) had substantial radioactivity uptake, but there were relatively less radioactivities in cortex and cerebellum. In PD SPECT image, the radioactivity uptake of BG had decreased in accordance with the disease severity. Conclusions 99mTc-TRODAT-1 may be a good radiopharmaceuticals for human brain DAT SPECT study, the preliminary results suggest that ? 99mTc-TRODAT-1 dat SPECT has clinical application values in the diagnosis and disease severity assessment for PD, Dopamine transporter (DAT) imaging of human brain central nervous system by positron emission computed tomography (PET) and single photon emission computed tomography (SPECT) is one of the hot fields in neuronuclear medicine research, which is to study the diseases associated with DAT changes, such as Parkinson's disease (PD), and to explore the clinical application value of DAT radionuclide imaging. At present, many radionuclide imaging drugs have been developed, such as [11C] CFT, [11C] methylphenidate [1], [123I] β- CTT, [123I] IPT [2-6] showed high affinity for DAT and good imaging properties. However, the radionuclides 123I and 11C used in the above imaging drugs need to be proced by accelerators, which limits their application in routine clinical examination. 99tcm-2 was successfully synthesized in 1996 by Kong HF and Kong MP β-〔 N. N ′ - bis (2-mercaptoethyl) ethylenediamine] methyl, 3 β-( 99mTc-TRODAT-1 has shown high dat affinity in animal experiments, and has obtained ideal dat SPECT images of human brain [7-9], which makes it possible to use dat radionuclide imaging for routine clinical application. In 1999, Fang Ping et al. First synthesized 99mTc-TRODAT-1 in China, and obtained the same results as Kong in animal experiments [10]. This paper reports the preliminary results of DAT SPECT imaging of human brain using 99mTc-TRODAT-1< Materials and methods

1.1 99mTc-TRODAT-1 kit was provided by the State Key Laboratory of the Ministry of health, Wuxi Institute of atomic medicine, Jiangsu Province μ g. Take a bottle and inject fresh 99mTc 3? 700 MBq (volume 1-2 ml), shake well, boil for 30 min, and cool at room temperature. The labeling rate and radiochemical purity of 99mTc-TRODAT-1 were more than 90%

1.2 subjects PD patients? Ten cases were diagnosed by capit (Core Assessment Program for internal transplantations) in neurology department of our hospital. They were aged from 60 to 77 years. The disease condition (modified Hoehn Yahr grade) was grade II to III. The course of disease was 2 to 10 years, with an average of 4.3 years. There were 8 normal volunteers, aged from 28 to 73 years old, including 6 males and 2 females

1.3 SPECT imaging method subjects were given potassium perchlorate orally on an empty stomach? 99mTc-TRODAT-1 740 MBq was injected into the elbow vein 0.5-1.0 hours later. Immediately, Toshiba gca-7 200 D / I SPECT was used with low-energy and high-resolution fan hole collimator (l.e.s.h.r. - (n.1) fanbeam). The energy peak is 140 keV, the window width is 20%, and the matrix is 128 × 128, probe rotation 360 °， Every 6 ° One frame is collected, 60 frames in total, and the acquisition time is 20-30 s per frame. Butterworth filter (order = 8, FC = 0.1-0.17) was used before image reconstruction, and ramp filter was used for reconstruction; Chang method is used for attenuation correction, and the attenuation correction coefficient is 0.15 cm-1; After correction with OM line, the transverse, sagittal and coronal three-dimensional sections were reconstructed respectively

2 Results

2.1 SPECT data acquisition and reconstruction were performed immediately after intravenous injection of 99mTc-TRODAT-1 in normal images, and the images obtained were basically consistent with 99mTc ECD regional cerebral blood flow (rCBF) SPECT images, as shown in Figure 1. It is suggested that the complex can rapidly accumulate in the brain through the blood brain barrier. In 3-4 hours SPECT imaging, the basal ganglia rich in dopamine transporter showed high radioactive uptake, while the dopamine transporter content in the brain was low or did not exist. There was little or no obvious radioactive concentration in other parts of dopamine transporter and cerebellum; SPECT images showed that bilateral basal ganglia had clear radiation images, symmetrical shape and size, and even distribution of radiation; See Figure 2. These results suggest that 99mTc-TRODAT-1 SPECT imaging can better display the number and distribution of dopamine transporters in striatum. The early whole body scan showed that there was more radioactive uptake in liver, lung, muscle and so on, and there was a large amount of radioactive concentration in intestines at the later stage, which suggested that 99mTc-TRODAT-1 was absorbed by liver and secreted into biliary tract, and excretion through intestines might be the main excretion pathway< According to the patient's condition and course of disease, the radioactivity uptake of basal ganglia in 10 patients decreased in varying degrees. The course of disease was short and mild (2-5 years, grade II, 6 cases). The radioactivity uptake of basal ganglia decreased to focal, showing the deformation of basal ganglia and uneven distribution of radioactivity; In the patients with long course of disease and severe condition (6-10 years of disease course, grade III disease, 4 cases), the radioactive uptake of basal ganglia showed diffuse decrease, even no obvious radioactive uptake, suggesting that the number and function of DAT were seriously damaged; The decrease of radioactivity uptake in bilateral basal ganglia was also significantly correlated with the severity of the disease. The decrease of radioactivity uptake was more obvious in the side with more severe disease and longer course of disease, as shown in Fig. 3 and 4. As shown in Figure 3, the patient's limbs had static tremor, including tremor of the left limb for 3 years and tremor of the right limb for 2 years. There was no obvious limitation in walking activities, and he was able to take care of himself; 99mTc-TRODAT-1 dat SPECT imaging showed that the basal ganglia on both sides were irregular in shape, uneven in radioactive distribution, and significantly reced in radioactive uptake. Compared with the two sides, the abnormality on the left side was more significant than that on the right side, suggesting that the number and function of DAT in the basal ganglia on both sides were damaged. The degree of damage on both sides was different, and the damage on the left side was more significant than that on the right side. As shown in Figure 4, the patient's course of disease is 10 years, movement is limited, and can't take care of himself; 99mTc-TRODAT-1 dat SPECT showed that there was no obvious radiation image of basal ganglia, suggesting that the number and function of dopamine transporters in bilateral basal ganglia were seriously damaged. These results suggest that 99mTc-TRODAT-1 dat SPECT imaging can provide an objective basis for the diagnosis of Parkinson's disease and an objective index reflecting the severity of the disease, which has important clinical value<

3 discussion

SPECT functional imaging of DAT is mostly used in clinical research and monitoring of neuropsychiatric diseases related to dopaminergic nervous system degeneration and degenerative disorders, including dyskinesia and schizophrenia. It is well known that the etiology of PD is the damage and progressive destruction of substantia nigra, which leads to the irreversible decline of substantia nigra striatum system. The substantia nigra is the most dense area of dopaminergic neurons, so dat in the dopaminergic nerve endings can directly reflect the lesion area of substantia nigra striatum. In SPECT imaging of DAT, the dopaminergic nerve in substantia nigra mainly projects to the striatum, and dat on its terminals is enriched in the striatum. Therefore, the basal ganglia striatum is generally used as the target area to observe the quantity and distribution of DAT radioactivity, while other brain regions such as occipital lobe and cerebellum are usually used as the reference area with little or no dat content. It was found that the radiation uptake rate of striatum in the experimental group (patients) was significantly lower than that in the control group (normal people). At the same time, in the PD group, the middle late PD group was significantly lower than the early PD group [12-14]. Our preliminary results also showed that the dat SPECT images of PD patients were significantly different from those of normal volunteers. It can be seen from the above that SPECT imaging of DAT can directly reflect the function and quantity of DAT, and the results are parallel to the severity of the disease, which can be used as an important index to evaluate the course of the disease< SPECT imaging of DAT also plays an important role in the differential diagnosis of dyskinesia. For example, it is difficult to distinguish dopamine responsive dystonia (DRD) from juvenile Parkinson's disease (JPD). Because both of them have similar clinical symptoms e to low dopamine level, and both of them are onset in adolescence. The difference is that the etiology, therapeutic effect and prognosis of L-dopa are different. The substantia nigra striatum system of DRD is intact, without progressive degeneration and irreversible degeneration of neurons, and without dat deletion. However, JPD belongs to the category of PD, which is irreversible degeneration of dopaminergic nerve in substantia nigra, low DA and progressive loss of dat. In 1997, Jeon BS et al β- SPECT imaging of CIT proved that the function and quantity of DAT in substantia nigra striatum system of DRD patients were normal. They found that the striatal radioactivity count and striatum / occipital lobe count ratio in PD and JPD patients were significantly lower than those in normal subjects and DRD patients, and the data results in DRD patients were almost the same as those in normal subjects. It is proved that SPECT can clearly and sensitively distinguish DRD from JPD and PD

the above results suggest that dat SPECT imaging has a broad application prospect in the study of PD. However, all the radiopharmaceuticals used in the above research are labeled with radionuclide 123I, which needs to be proced by accelerator, and the labeling process is complex, so it is difficult to popularize and use. Therefore, it is very important to develop an ideal radiopharmaceuticals for DAT SPECT imaging (high specificity, easy to popularize and use). 99mTc is an ideal radionuclide, so it is necessary to develop 99mTc labeled dat SPECT imaging drugs. 99mTc-TRODAT-1 is a new radiopharmaceutical. The animal experiments of Kong HF, Fang Ping, et al. And the studies of normal people showed satisfactory results [7 ～ 10]. Our preliminary results suggest that 99mTc-TRODAT-1 is an ideal radiopharmaceutical for DAT SPECT imaging< br />
Fig.1 SPECT images with 99mTc-TRODAT-1 normal human brain acquired at 30 min.post-injection The radiocactivity d

8.

Many small white just admission, was the private key, public key, address, and other relations confused. Some of them even lost their private key. They had money on the address, but they just couldn't get it out. Today, Xiao will try to figure out the relationship between the private key, the public key and the address

The relationship among

private key, public key and address is as follows:

the private key is converted into (generated) public key, and then converted into address. If there is bitcoin or integrity coin on an address, you can use the private key converted into this address to spend the above integrity coin. The generation of public key and address depends on private key, so private key is the most important

The same is true for mobile phone wallet, but the file management method of mobile phone is not as convenient as that of computer. Therefore, the general mobile wallet will provide a function called or similar to "export private key". Through this function, the private key can be exported in various forms

for example, bitcoin mobile wallet can be exported as a two-dimensional code, which can be printed or scanned on paper. When replacing a mobile phone, install a bitcoin wallet and scan the QR code to migrate bitcoin. Bitcoin mobile wallet and trustcoin mobile wallet can be exported as a clear text string and printed on paper - this is paper wallet

paper wallet allows users to spend your bitcoin or trustcoin at any terminal with bitcoin or trustcoin wallet

the loss or damage of the wallet will lead to the loss of the private key, thus completely losing the transfer right of the digital currency. To prevent such tragedies, you should always back up the data in your wallet. In addition to the address, all the private keys are saved ring the backup

summary

1, the private key should be well protected to prevent loss and forgetting. When the mobile phone clears the information, it is best to it by hand, but do not disclose it

2, you should prevent your wallet from being lost or damaged, resulting in the loss of your private key and the right to transfer in digital currency. Otherwise, you can't take out more than one currency, which is not useless

9. MPEG / mpg / datmpeg is the abbreviation of motion picture experts group. This kind of formats include MPEG-1, MPEG-2 and MPEG-4. MPEG-1 is believed to be the most popular one, because at present it is widely used in the proction of VCD and the network application of some video clips downloading. Most VCDs are compressed in MPEG1 format (recording software automatically converts MPEG1 to MPEG). Dat format), using MPEG-1 compression algorithm, a 120 minute long movie can be compressed to about 1.2 GB. MPEG-2 is used in DVD proction, and also in some HDTV (high definition television broadcasting) and some high demand video editing and processing. Using MPEG-2 compression algorithm to compress a 120 minute long movie can be compressed to 5-8 GB (the image quality of MPEG-2 is incomparable with that of MPEG-1). MPEG series standards have become the most influential multimedia technology standards in the world. MPEG-1 and MPEG-2 are the first generation data compression coding technologies based on Shannon's principle, such as predictive coding, transform coding, entropy coding and motion compensation; MPEG-4 (ISO / IEC 14496) is an international standard based on the second generation compression coding technology. It takes audio-visual media object as the basic unit and adopts content-based compression coding to realize the integration of digital audio-visual, graphics synthesis application and interactive multimedia. MPEG series standards have a great and far-reaching impact on the development of audio-visual consumer electronics such as VCD, DVD, digital television, high definition television (DTV & & HDTV), multimedia communication and other information instries. Aviaviavi, short for audio video interleaved. Avi, a video format published by Microsoft, is one of the oldest in the video field. Avi format is the most widely used format because of its easy to call, good image quality and optional compression standard. Mov friends who have used Macs should have been exposed to QuickTime more or less. QuickTime was originally an image and video processing software used by apple for MAC computers. Quick time provides two standard image and digital video formats, that is, it can support static *. Pic and *. JPG image formats, dynamic *. Mov based on indeo compression method and *. Mpg video format based on MPEG compression method. Asfasf (Advanced Streaming Format). ASF is a file compression format developed by Microsoft in order to compete with the current real player, which can directly watch video programs on the Internet. ASF uses MPEG4 compression algorithm, the compression rate and image quality are very good. Because ASF is a video "stream" format that can be watched on the Internet, it is not surprising that the image quality of ASF is a little worse than VCD, but better than RAM format which is the same video "stream" format. Wmv is a technical standard for real-time transmission of multimedia on the Internet independent of coding mode. Microsoft hopes to replace the technical standards such as QuickTime and file extensions such as WAV and avi with WMV. The main advantages of WMV are: scalable media types, local or network playback, scalable media types, stream prioritization, multilingual support, scalability, etc. If Navi finds that the original playback software can't open avi files in this format, you have to consider whether you have encountered n avi. Avi is the abbreviation of new avi. It is a new video format developed by an underground organization named shadow realm. It is a modification of Microsoft ASF compression algorithm (not AVI in imagination). The video format pursues nothing more than compression rate and image quality. Therefore, in order to pursue this goal, Navi improves some shortcomings of the original ASF format, so that Navi can have a higher frame rate. It can be said that Navi is an improved ASF format without video stream characteristics. 3gp3gp is a video coding format of 3G streaming media, which is mainly developed to match the high transmission speed of 3G network. It is also the most common video format in mobile phones. In short, the format is a multimedia standard developed by 3GPP, which enables users to enjoy high-quality video, audio and other multimedia content on their mobile phones. Its core consists of advanced audio coding (AAC), adaptive multi rate (AMR) and MPEG-4 and H.263 video codec. At present, most mobile phones supporting video capture support 3GPP video playback. Real video easy video (RA, RAM) format from the beginning is positioning, is in the application of video streaming, can also be said to be the founder of video streaming technology. It can be used in 56K modem dial-up Internet conditions to achieve uninterrupted video playback, of course, its image quality and MPEG2, DivX and other ratio is not flattering. After all, to achieve uninterrupted video transmission on the Internet requires a lot of bandwidth, which is a strong competitor of ASF. Mkv, a video file with MKV suffix, appears frequently on the network. It can integrate multiple different types of audio and subtitle tracks in a file, and its video coding freedom is also very large. It can be common DivX, XviD, 3ivx, and even streaming video such as realvideo, QuickTime, WMV. In fact, it is a new multimedia packaging format called Matroska. This advanced and open packaging format has shown us a very good application prospect. Flvflv is the abbreviation of flash video, flv streaming media format is a new video format. Because of its small file size and fast loading speed, it makes it possible to watch video files on the network. Its appearance effectively solves the shortcomings of importing video files into flash, such as the huge volume of exported swf files, which can not be used well on the network. Flvflv is the abbreviation of flash video, flv streaming media format is a new video format. Because of its small file size and fast loading speed, it makes it possible to watch video files on the network. Its appearance effectively solves the shortcomings of importing video files into flash, such as the huge volume of exported swf files, which can not be used well on the network. F4v as a smaller, clearer, more concive to spread in the network format, f4v has graally replaced the traditional flv, and has been compatible with most mainstream players, without the need for complex ways such as conversion. F4v is the f4v streaming media format which supports H.264 after FLV format launched by Adobe in order to meet the high definition era. The main difference between flv and flv is that FLV format adopts H263 encoding, while f4v supports h.264-encoded high-definition video, with a bit rate up to 50Mbps. That is to say, f4v and flv can achieve higher resolution and support higher bit rate on the premise of the same volume, which is what we call clearer and smoother. In addition, the suffix of f4v files downloaded from many mainstream media websites is flv, which is another feature of f4v format. It is a normal phenomenon. When watching, you can obviously feel that this kind of FLV, which is actually f4v, has significantly higher clarity and fluency. I use WMV in all my videos. It's small and clear