Can Changzhou 33 go to Changzhou media center

1. There are two ways to calculate instrial added value: proction method and income method<

the proction method is to use the total output value minus all material consumption, and the formula is:
instrial added value = total instrial output instrial intermediate input
from the accounting point of view, the intermediate input here includes the materials in inventory, fixed assets, management expenses and sales expenses (office supplies, machinery and materials consumption, water and electricity expenses, etc.), as well as the labor expenses paid by other enterprises, etc, In short, purchase or payment related to input tax is basically included

the income method includes the value of finished procts proced in the current period, the income from external processing fee and the difference value of self-made semi-finished procts at the end and beginning of the term
formula:
instrial added value = labor remuneration + depreciation + tax + profit
the above data can be basically found in the income statement. Depreciation view accumulated depreciation account

theoretically, the calculation results of the two methods should be consistent, but in practical application, the calculation results are often the same. The reason is that some values are different, such as the confusion between operating profit and total profit. Therefore, we should pay attention to this point when using different methods to calculate the added value

the general statistical yearbook will have the index of added value of each instry.

2. When it comes to the front end of learning, many Xiao are worried. Is it self-study or a training class
before you consider applying for a class, you should first make sure whether you are suitable for learning. Only when we have a clear learning goal and a direction, can we take root in this field
secondly, combined with their own situation, choose the appropriate way of learning. If you have good self-control, you can improve your technical level through self-study. This may lead to more detours, but if you persist, some people will still reach the destination. As for when to arrive, it depends on the time you spend, the speed you walk, the length of the road and other factors. But if your foundation is weak, and self-control is not very good, it is recommended to choose a reliable training institution, in-depth and systematic to improve their technical ability
and if you are lucky enough to find an organization that has a good curriculum system and can participate in multiple project development, when you graate from training, your entry salary will even be higher than that of many technicians who directly enter the enterprise after graation
although technology is the key to it skills, ecation is the second. But now most enterprises are required to recruit college degree or above, if you do not have a stepping stone, it is recommended that you at least get a degree at the same time. For those with low ecation background who have never been in touch with computers or even basic computer operation, it is certainly difficult for them to learn the front-end, and they should not torture themselves to learn the front-end. For zero foundation or career change, if you want to enter quickly, choosing training class is a better choice
of course, no matter how good the training institution is, if you don't study hard, the result will not be satisfactory. Ecation is not only "teaching", but also "learning". The final result of ecation is decided by both teachers and students. So whether it is self-study or training depends on whether you are willing to spend time and energy and really want to develop in the IT instry for a long time.

4.

Principle: each cell of telephone dial is a pulse, dial 1 to one cell, dial 9 to nine cells, that is, you can hear the click 9 times. Each corresponding position is connected with a pulse, missed position is broken, the next grid is another pulse, 0 is 10 pulses

for ordinary telephone, you can also dial the phone by directly pressing the switch to hang up the phone without pressing the key. For example, you can dial the phone by taking 8 shots in a row, pausing for 7 shots, pausing for 9 shots, pausing for 10 shots, pausing for 5 shots

pause for 6 shots, pause for 6 shots, pause for 3 shots. If the operation is correct, the phone will be dialed. Every beat is a pulse

extended data

wired telephone:

the telephone has the function of converting the terminal's sound wave into electronic signal, transmitting it to the remote party through the telephone line, regenerating the electronic signal transmitted by the other party into voice (sound wave), making it communicate, and sending the signal (dial pulse) that can be selected from multiple parties, Inform the other party of the call tone and other functions

a telephone consists of a transmitter that converts voice into current and sends it to a telephone line, a receiver that restores the current transmitted by the other party to voice, a dialing or button that calls the other party, a ringing tone that sends the call tone, and a line network that connects these lines to perform its functions on the telephone line. There is a small box filled with carbon particles in the transmitter, and there is a thin hard aluminum alloy vibrating plate in front of it

the vibration plate vibrates the carbon particles according to the voice, and the carbon particles conct the current. With the contact degree of the particles, the resistance changes, and the voice current is generated. After receiving the voice current from the other party, the receiver generates the magnetic force caused by the voice current on the coil, vibrates the iron vibrating plate and makes a sound

5. ADSL dialing process

ADSL: asymmetric digital subscriber loop, because the uplink and downlink rates are not the same, so it is called asymmetric! Theoretically, the downlink rate can reach 8m and the uplink rate can reach 1m

DSLAM: ADSL access device at the office end. It provides access and centralized multiplexing functions for ADSL remote devices, and provides flow control of asymmetric data flow< ATM: asynchronous transfer mode. In essence, it is a fast packet switching mode. Now we mainly know his two main concepts: VPI / VCI.

VPI / VCI: virtual path / virtual channel label. Very simple, we think of it as a model of a large pipe (VPI) with a small pipe (VCI), in which data is transmitted

when we want to access the Internet and turn on the cat, the cat should first shake hands with DSLAM. Now I know most of the devices, this section is the ATM protocol There are several VPI / VCIs set inside the cat. According to the setting of the DSLAM at the local end, select the corresponding one to connect (this value is generally unchanged). DSLAM is connected to switch core switch core router backbone router

after synchronization, we set up a dial-up connection, click Connect and start sending PPP protocol messages! Because the cat and PC go through IP protocol, and the cat and DSLAM go through ATM protocol, it needs to be converted into ATM cells and go through ATM channel. Then it is sent to DSLAM, and then it is converted to IP protocol through DSLAM. After it is transmitted through switch, note: there is a bas on the core router, which is mainly responsible for terminating the function of PPP protocol message. The message is sent to bas, and bas receives the PPP request. Check the user name and password, and then assign IP and DNS according to the IP address pool. In this way, we get the public IP and can access the Internet.

6. Internet is no longer unfamiliar to everyone, and now it has entered into the family of the broad working class. More and more companies have their own internal network access to the Internet. Of course, there are many ways to access the Internet. For ordinary people, it is to buy a modem and use PSTN (public service telephone network) to access the Internet. And some companies generally use DDN or ISDN access, using the way of monthly rent. Of course, indivials can not afford to rent a month, so how to use a telephone line to make many people online? This involves the proxy server and how to use it

what is proxy? It's proxy. Common internet access is a typical structure of client and server: users send requests by using client programs, such as browser, and remote WWW server programs respond to requests and provide corresponding data. The proxy is between the client and the server. For the server, the proxy is the client. The proxy makes a request and the server responds; For the client, proxy is the server, which accepts the request of the client and transfers the data uploaded by the server to the client. Its function is very similar to the real life agent service provider. Therefore, the Chinese name of proxy server is proxy server

the working principle of proxy server is: when the client sets up the proxy server in the browser, the request for accessing all WWW sites using the browser will not be sent directly to the destination host, but will be sent to the proxy server first. After the proxy server accepts the client's request, the proxy server sends the request to the destination host and receives the data of the destination host, It is stored in the hard disk of the proxy server, and then the proxy server sends the data required by the client to the client< There are four functions of proxy server:

first, improve the access speed. Because the data required by the client is stored in the hard disk of the proxy server, the next time this client or other clients ask for the data of the same destination site, they will directly read it from the hard disk of the proxy server. The proxy server plays a role of caching. When there are many clients visiting the popular sites, the advantage of the proxy server is more obvious< Second, proxy can act as a firewall. Because all users who use proxy server must access remote sites through proxy server, corresponding restrictions can be set on proxy server to filter or block some information. This is the most common way for LAN network management to limit the access scope of LAN users, and it is also the reason why LAN users can't browse some websites. If dial-up users use a proxy server, they must also obey the access restrictions of the proxy server, unless you do not use the proxy server

Third, access some websites that cannot be accessed directly through proxy server. There are many open proxy servers on the Internet. When the client's access rights are limited, the access rights of these proxy servers are unrestricted. Just because the proxy server is within the scope of the client's access, it is possible for the client to access the target website through the proxy server. Domestic colleges and universities use the ecation network, can not go abroad, but through the proxy server, can achieve access to the Internet, this is the reason for the popularity of proxy server in Colleges and universities< Fourthly, the security is improved. Whether you go to chat room or browse website, the destination website can only know that you are from proxy server, but your real IP can't be detected, which improves the security of users
proxy server settings:

to set a proxy server, you must first know the proxy server address and port number, and then fill in the corresponding address and port number in the proxy server settings column of IE or NC. Suppose we have a proxy server with an address of proxy.net.net and a port number of 3000. The configuration method in IE is to use the Internet Options / connection / proxy server in the View menu, then check the check box in front of the Internet access through proxy server option, and fill in the proxy server address in the address box, For example, assume that the proxy server address is proxy.net.net, fill in the port number 3000 in the port box, click the application button at the bottom, and then click OK to complete the setting. The next time you use IE, users will find that no matter what website you visit, ie always connects with the proxy server first. With NC, the setting is a little more complicated. Use the Preferences menu item under the edit menu, and then select proxies under advanced. At this time, select the second manral proxy configuration in the proxies option on the right, and then click the view... Button on the right. The proxy server configuration interface will appear. Fill in the corresponding contents in the proxy server address and port number column, and click OK to return to the parameter setting window, Then click OK, and the setting of the proxy server is completed. When the client browses the web page again, it will automatically send an application to the proxy server you set and get the data. When browsing the website, whether it is IE or NC, you can clearly see the process of connecting the proxy server first and then the target website in the browser status bar

however, do not confuse proxy server with router. Proxy server is a service software built on the application layer, while router is a network device or a computer, which works on the IP layer, and the data will be forwarded when it arrives at the IP layer. Generally, a proxy server works on a computer with modem and network card. Different proxy server software provides different services, generally providing WWW, FTP and other common services. In the intranet, each airliner must have an independent IP address, which is located in the & quot; Control panel - Internet item & quot; Middle & quot; Connect & quot; Configure the port number that uses proxy server and points to the IP address and service of proxy server. When the proxy server starts, it will use winsock.dll to open a specified service port and wait for the request of the airliner. When the modem of proxy server dials up the Internet, your proxy server can work. When you send a connection request in your IE, your airliner will directly send the packet to the proxy server. When the server captures the IP packet, it first needs to analyze what the request is. If it is an HTTP request, the proxy server will send an HTTP request to your ISP. When the proxy server receives the response, it will forward the IP packet to the internal network, and your airliner will get the IP packet. In addition, your proxy server can also be used as a good firewall. For specific operation, please refer to the readme file of your proxy server

when you visit a web server on the Internet, do you know how much personal information will be leaked to others? In the process of accessing the Internet, the web browser will at least send more than 20 personal information to the web server without your awareness. If these personal information is transmitted to a well-known website or the web server of a large enterprise, there will be no big problem. If it's sent to a web server that doesn't even know who started the website, it's very disturbing. The information that a web browser sends to a web server is & quot; in jargon; Environment variable & quot;. The main contents are: (1) IP address (remote a DDR) and host name (remote host) assigned to the computer 2) The port number (remote port) used by the web browser 3) The proct name of the web browser (HTTP user agent) 4) The latest web page address (HTTP reference) of the visited website

although the above items do not contain personal information such as e-mail address and name, the security of IP address and host name in (1) is hard to be assured, but what kind of method can we take to hide our IP address

solving this problem is actually very simple. Just visit the web server through the proxy server. The function of proxy server is that it can bear the access request from each terminal for web server. In the enterprise network, the proxy server is set up on the part of LAN and Internet in the company. When dialing the Internet, you can use the proxy server provided by the Internet connection provider.

7.

Mobile phone call answering principle:

voice upload (talking): after the voice is received by the microphone, it is a low-frequency analog signal, which is converted into a digital signal by an analog-to-digital converter. Through the "fundamental frequency chip", it carries out data compression, adding cyclic repeat check code, channel coding, interleaving, encryption, formatting, and then carries out digital signal processing such as multiplexing and molation

next, it is converted into high frequency digital signal (electromagnetic wave) through "if chip" (high frequency analog-to-digital converter); Finally, the electromagnetic waves with different time, frequency and waveform are formed through the "RF chip" and transmitted by the antenna

voice download (listening to the phone): the antenna receives electromagnetic waves of different time, frequency and waveform, processes them by "RF chip" to get high-frequency digital signals (electromagnetic waves), and then converts them into digital signals by "if chip", that is, high-frequency digital to analog converter (ADC)

next, the digital signal processing such as demolation, de multiplexing, de formatting, de ciphering, de interleaving,

channel decoding, CRC and decoding are performed through BB, Finally, it is converted into low-frequency analog signal (sound) by low-frequency digital to analog converter (DAC) and played out by microphone

extended data:

signal generation

DTMF encoder is based on two second-order digital sine wave oscillators, one is used to generate row frequency and the other is used to generate column frequency. By loading the corresponding coefficients and initial conditions into DSP, only two oscillators can generate eight audio signals

the typical frequency range of DTMF signal is 700 ~ 1700Hz, selecting 8000Hz as the sampling frequency can meet the Nyquist condition. DTMF al audio signal is generated by two second-order digital sinusoidal oscillators, one is used to generate row audio signal, the other is used to generate column audio signal

proction process

CCITT stipulates that at most 10 keys are pressed per second, that is, the shortest time slot of each key is 100ms, in which the actual ration of audio is at least 45ms, not more than 55ms, and the rest of the time slot remains silent, so when the key generates al audio signal, the successive two signals are separated for a period of time; The decoder uses this time to identify the al audio signal and convert it into the corresponding digital information,

and to identify the gap information. Therefore, the process includes audio task and silent task. The former generates double audio sample value, while the latter generates silent sample value. At the end of each task, the timer and the next task should be reset. One task is added to the silent task: extract the number from the digital buffer and unpack it. Unpacking is to map the number to the corresponding row and column audio characteristics,

Load pointer points to the correct position corresponding to the oscillator characteristic table. The two tasks take turns. According to CCITT (International Telegraph and Telephone Advisory Committee), there must be an appropriate length of silence between the numbers. Therefore, the encoder has two tasks: one is the audio signal task, which generates two tone samples; the other is the mute task, which generates mute samples. At the end of each task,

before starting the next task (audio signal task or mute task), the timer variable that determines its ration must be reset. At the end of the mute task, DSP moves the next number from the digital cache to determine the number. And the initialization parameters are determined according to different frequencies

The task of the decoder is to transform it from time domain to frequency domain through mathematical transformation, and then get the corresponding digital information. Because the chip processes digital signal, the input signal must be digitized and then processed by DSP chip

in frequency detection, the fundamental and second harmonic of DTMF signal are detected. DTMF signal only has higher energy on the fundamental, while voice signal has stronger second harmonic superimposed on the fundamental. The function of detecting second harmonic is to distinguish DTMF signal from language and music signal

8. Where are the dial-up VPS mainly used
first, account registration account class
most new websites need to have a certain amount of user registration when they are built. In general, the website registration requires not only independent account information, but also independent IP, that is, different accounts have to register accounts and login under different IP addresses. At this time, the dynamic VPS dial-up server that can change IP becomes the best choice for these services. In other words, in a specific VPS, the IP address is fixed, but with the dynamic change of VPS, the address also changes
Second, data collection
the purpose of establishing a website is not to better publicize business, but as a tool to deal with business. In this case, a more efficient dynamic VPS dial-up server is needed
enterprises can obtain dynamic IP address with the help of purchased VPS service. In the development process of many enterprises, the number of computers is insufficient. In order to better expand its functions and obtain more information processing space, dynamic VPS is a good choice
Third, optimize information
enterprises that do optimize information also need to use some operations to optimize the target keywords, ranking top. When SEO optimization articles are published on different IP, they can effectively achieve the goal. The dynamic VPS dial-up server can meet the IP consumption of these enterprises. For example, the dial-up VPS can select Aurora VPS, which can run the above situation.

9. Can refer to each step of the scarecrow dynamic analysis of the implementation, because the principle is universal