Who sent the public key and private key in the blockchain

3. Today, I'd like to show you what you don't know about social workers...
in the embryonic stage
before 2006, social work in our province had not been included in the scope of work of Party committees and governments at all levels
with the increasingly frequent exchanges in the field of social services between Guangdong, Hong Kong and Macao, some social service institutions in Guangzhou began to explore social work practice since the 1990s. For example, Fengyuan street in Liwan District of Guangzhou cooperated with neighborhood counseling association to provide social work services to meet the needs of residents for community services; Guangzhou old people's home cooperated with Hong Kong Sheng Kung Hui to introce professional social workers to implement social work services for the elderly in homes; Some social organizations such as Guangzhou YMCA also try to introce social workers to accumulate practical experience< On the other hand, social work ecation started. Since 1999, South China Agricultural University, Guangdong Business University, Sun Yat sen University, Guangzhou University, Guangdong University of technology and other universities have set up social work programs
the social work service practice explored by social forces and the development of social work professional ecation have laid a certain foundation for the start of social work in our province< In 2006, after the Ministry of Civil Affairs held the national civil affairs system social work talent team construction promotion meeting in our province, our province quickly launched the pilot exploration, graally built social work demonstration areas in all parts of the province, strengthened the decision-making and coordination on major issues of social work, and steadily promoted the pilot work. Comprehensive promotion stage (2011 to present)
in 2011, the ninth meeting of the 10th CPC Guangdong Provincial Committee focused on strengthening social construction. The general office of the CPC Guangdong Provincial Committee and the general office of the provincial government issued the implementation opinions on strengthening the construction of social work talent team, and included "the number of social workers with certificates per 10000 people" into the evaluation index system of "happy Guangdong", The social work of our province has entered the stage of comprehensive promotion
the practice of social work has been graally deepened, and the service field has graally expanded from social welfare and social assistance to disability rehabilitation, drug control and ecation, community correction, employment assistance, employee assistance, dispute mediation, emergency response and other fields. The service area has expanded from urban areas to rural areas, and the service object has extended from children and adolescents, the elderly, the disabled to the floating population, the elderly and the disabled Disaster victims, women with special needs and other groups
social work professionals and social work service institutions are the main bodies that directly provide social work services. All parts of our province take the cultivation and expansion of social work talents and social work service institutions as the core of the development of social work, promote social work talents to take root in the front line to do service, and social work service institutions to build brand based on the long-term
judging from the government's emphasis on social work, Xiaobian thinks that social workers will graally appear as a profession, which is not only to distinguish them from the enthusiastic aunts of the neighborhood committee, but also to distinguish a mode of helping others and solve the existing problems in depth
social workers may be needed by more people in the future. If you have a social worker card at this time, it will be even better.

4. Of course it's true. But bitcoin is the representative of digital currency, cryptocurrency. According to the current 24-hour market of China currency, the highest price of bitcoin is 73900.00 QC (equivalent to RMB)
When did you buy 500? Now you make a lot of money

5. Meili chain realizes the implementation of blockchain application scenarios. Meili chain is a decentralized proct. Public key and private key are like your own bank card password, but the password cannot be retrieved. Personal information can only be saved by yourself, and no other platform or indivial can control it. Public key and private key are the verification information needed to retrieve an account, and only you can have them, Once lost, it will never be found again, and the assets will never be found back, so the public key and private key are very important.

6. DES is symmetric encryption. There is only one key

7.

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

8. Calculation method:
according to the provisions of "9 flange" in p94 of steel pressure vessels (GB 150-1998), the compression force of gasket is obtained, and then the torque of each bolt is calculated according to the relationship between force and torque. The dimension of high pressure flange is dn6'pn1500class (spiral wound gasket seal), and the experience calculation of flange pre tightening force is as follows:
1. Check hg20631-97 flange sealing surface outer diameter d = 216mm in hg20592 ~ 20635-97 steel pipe flange, gasket and fastener
2. Check the dn6'pn1500d spiral wound gasket in hg20631-97, inner diameter of spiral wound gasket D2 = 171.5mm, outer diameter of spiral wound gasket D3 = 209.6mm, gasket sealing width n = 19.05mm, D3 < D
3. According to 1a in table 9-1 of GB150-98 P91, the basic sealing width of gasket B0 = n / 2 = 19.05/2 = 9.525mm ＞ 6.4mm
4. According to 9.5.1.1 of GB150-98 p94, the effective sealing width of gasket B = 2.53 = 2.53 = 7.81mm
5. According to 9.5.1.2 of GB150-98 p94, the diameter of center circle of gasket pressing force is DG = d3-2b = 209.6-2 * 7.81 = 193.98mm
6. Check the gasket coefficient M = 3.00 and specific pressure y = 69mpa of spiral wound gasket in table 9-2 of GB150-98 p93. The design pressure of the pipeline is 15.85 MPa and the operating pressure is 14.4 MPa
7. According to 9.5.1.3 of GB150-98 p94, the minimum gasket pressing force FG = FA = 3.14dgby = 3.14 * 193.98 * 7.81 * 69 = 328236.4n
8. According to 9.5.1.3 of GB150-98 p94, the minimum gasket pressing force FG = FB = 6.28dgbmpc = 6.28 * 193.98 * 7.81 * 3.00 * 14.4 = 411009n
9. According to the relationship between force and torque, n = 0.2fd, the flange bolt is M36 * 3, 12 pairs of bolts are used, and the actual force diameter of thread is d = 33
10. Under pre tightening condition, the loading torque of each bolt Na = 0.2 (FG / 12) d = 0.2 * (328236.4 / 12) * (33 / 1000) = 180n. M
11. Under the operation state, the loading torque of each bolt is NP = 0.2 (FG / 12) d = 0.2 * (411009 / 12) * (33 / 1000) = 226n. M
the above is the loading torque of each bolt calculated according to the flange requirements of GB150. When it is applied to the actual work, the torque wrench can fully meet the requirements, but in the actual work, the torque wrench is 30%, 50% and 100% of the pre tightening torque. Under the action of 100% pre tightening torque, tighten several times.