Electronic component btc3syh

1.

BTC (business to customer)

also known as B2C, e-commerce according to a classification of trading partners, that is, commercial institutions to consumers of e-commerce. This form of e-commerce is generally based on the network retail instry, mainly with the help of the Internet to carry out online sales activities

B2C mode is the earliest e-commerce mode in China, marked by the formal operation of 8848 online mall. B2C means that enterprises provide consumers with a new shopping environment through the Internet - online store, where consumers shop online and pay online

because this mode saves the time and space of customers and enterprises, and greatly improves the transaction efficiency, especially for busy office workers, this mode can save valuable time

two BTB (business to business)

also known as B2B, refers to a kind of Internet market, which is the marketing relationship between enterprises. It combines the intranet with customers through B2B website, and provides better service for customers through the rapid response of the network, so as to promote the business development of enterprises. In recent years, B2B develops rapidly and tends to be mature

three otos (online to offline)

also known as o2o, namely "online to offline". The core of the business model of oto is very simple, which is to bring online consumers to real stores, pay online to buy offline goods and services, and then enjoy offline services

extended materials:

e-commerce is a business activity with information network technology as the means and commodity exchange as the center; It can also be understood as the activities of trading activities and related services in the form of electronic transactions on the Internet, intranet and value-added network. It is the electronization, networking and informatization of all aspects of traditional business activities

e-commerce usually refers to a wide range of business and trade activities all over the world, in the Internet open network environment, based on Browser / server application mode,

buyers and sellers do not meet each other to carry out a variety of business activities, to achieve consumer online shopping, online transactions and online electronic payment between merchants, as well as a variety of business activities, trading activities Financial activities and related integrated service activities are a new business operation mode

governments, scholars and business people in various countries have given many different definitions according to their own status and different angles and degrees of participation in e-commerce. E-commerce is divided into ABC, B2B, B2C, C2C, B2M, M2C, B2A (B2G), C2A (C2G), o2o, etc

At the same time, network marketing is also a proct of e-commerce, and for network marketing, it is necessary to make a good network marketing plan before doing it, so as to facilitate the implementation of the plan

since October 1, 2018, the Ministry of finance, the State Administration of Taxation, the Ministry of Commerce and the General Administration of customs have jointly issued the new regulations on tax exemption for e-commerce export enterprises in the comprehensive pilot zone of cross border e-commerce

2.

1. BTC: chemical vocabulary

BTC is the abbreviation of (Trichloromethyl) carbonate. It is the abbreviation of a chemical substance, mainly composed of carbon, chlorine and oxygen. The chemical formula is c3cl6o3, which can be used as the substitute proct of highly toxic phosgene and diphosgene in the synthesis

BTC: enterprise abbreviation

BTC refers to BTC Yingqun enterprise from Taiwan, China, which is a large-scale high-tech enterprise developing and procing keyboard, mouse and recorder. BTC is famous for procing high-quality computer peripherals. BTC is the OEM keyboard and add-on card proced by famous brand EMPREX, ranking first in Taiwan, especially the third in the world

BTC: the concept of bitcoin was first proposed by Nakamoto on November 1, 2008, and was formally born on January 3, 2009. According to the idea of Nakamoto, the open source software is designed and released, and the P2P network on it is constructed. Bitcoin is a virtual encrypted digital currency in the form of P2P. Point to point transmission means a decentralized payment system

BTC: engineering material

BTC (buttress thread coupling), full name of partial trapezoidal thread coupling, is an API standard thread connection type, which is commonly used in the connection of petrochemical pipes or tools, such as floating collar, guide shoe and pipe shoe used in cementing operation

5, BTC: e-commerce mode

BTC (business to customer) e-commerce is one of the categories of e-commerce by trading partners, that is, e-commerce of commercial institutions to consumers. This form of e-commerce is generally based on the network retail instry, mainly with the help of the Internet to carry out online sales activities. BTC is also known as B2C, B2C mode is the earliest e-commerce mode in China

3. They are all excellent digital currencies. We recommend the coin easy platform, support RMB direct recharge purchase, recharge withdrawal and instant account arrival!

4. Here's the standard list, with the download address<

serial number standard name Chinese name

1 IPC j-std-001f ★ requirements for welding electrical and electronic components j-std-001 is the only internationally recognized specification covering welding assembly materials and processes with instry consensus. The
standard is perfectly complementary to ipc-a-610 and contains lead-free
manufacturing information. This standard has made
requirements for three levels of procts, and has color illustrations. It has more easily understood materials, methods and
inspection standards for
procing high-quality welded interconnects and components

2 IPC j-std-002d Solderability test of terminals and wires

3 IPC j-std-003c PCB solderability test

4 IPC j-std-004b} flux requirements

5 IPC j-std-005a} solder paste requirements

6 IPC j-std-006c electronic solder alloy and solder alloy with and without flux Requirements for solid solders

7 humidity Reflow Sensitivity Classification of IPC j-std-020e unsealed solid surface mount components

8 selection and application of IPC j-std-030 plate level underfill materials

9 IPC j-std-033c disposal, packaging, packaging, packaging of humidity and reflow sensitive surface mount components Shipping and using methods

10 IPC j-std-035 acoustic microscope for non hermetically packaged electronic components

11 IPC j-std-075 classification of non IC electronic components in assembly process

12 IPC j-std-609b components, printed circuit board and printed circuit board components Marking and labeling of lead-free and other properties

13 IPC / whma-a-620b
★ requirements and acceptance of cable and harness components

14 ipc-1401 guidelines for supply chain social responsibility management system

15 ipc-1601 guidelines for operation and storage of printed circuit boards

16 ipc-1710 original manufacturer of printed circuit boards Qualification manual

17 ipc-1720a assembly qualification outline

18 ipc-1751 declaration process management general requirements

19 ipc-1752 material declaration management

20 ipc-1755 conflict minerals data exchange standard

21 ipc-2141 impedance controlled high speed circuit board design Guideline

measurement standard of current carrying capacity in 22 ipc-2152 PCB design

23 ipc-2221b PCB design general standard

24 ipc-2222a rigid organic PCB design sub standard

25 ipc-2223c flexible PCB design sub standard

26 ipc-2224 PC card PCB design sub standard

27 ipc-2225 organic multi chip mole (mcm-l) and mcm-l
mole design sub standard

28 ipc-2226 high density interconnection (HDI) PCB design sub standard

29 ipc-2252 RF / microwave PCB design guide

30 ipc-2291 IPC / JPCA printed electronic device Design guidelines

31 ipc-2581 PCB assembly proct manufacturing description data and transmitter
General requirements

32 ipc-4101d rigid and Multilayer PCB substrate specification

33 ipc-4103 high speed / high frequency application substrate specification

34 ipc-4104 IPC / JPCA high density interconnection (HDI) and micro conction
hole material specification

35 ipc-4121 is a guide for selecting core buildings for multilayer printed circuit board applications, Replace ipc-cc-110a

36 ipc-4202a flexible substrate dielectric for flexible printed circuit

37 ipc-4203 for covering and bonding material of flexible printed circuit

38 ipc-4204a-wam1 flexible metal foil dielectric material for flexible printed circuit

39 ipc-4412b treated "e" glass for printed circuit board Fiber cloth specification

40 ipc-4552 PCB electroless nickel / immersion gold (ENIG) coating specification

41 ipc-4553 PCB silver immersion specification

42 ipc-4554 PCB tin immersion specification

43 ipc-4556 PCB Electroless nickel / palladium / immersion gold (ENEPIG)
coating specification

44 ipc-4562a Metal foil for printed circuit board

45 ipc-4591 IPC / JPCA functional conctive material requirements

46 ipc-4921 IPC / JPCA printed electronic substrate (substrate) requirements

47 ipc-6010 printed circuit board identification and performance series standards

48 ipc-6011 printed circuit board general performance specification

49 Ipc-6012d rigid pcb qualification and performance specification

50 ipc-6013c flexible PCB qualification and performance specification

51 ipc-6015 organic multi chip mole (mcm-l) installation and interconnection
structure qualification and performance specification

52 ipc-6016 high density interconnect board qualification certification and inspection specification

53 Ipc-6017 is a supplement to the existing ipc-6010 series, To provide the qualification and performance specification of in-process and finished printed circuit boards containing embedded passive circuits (distributed capacitor
layer and capacitor or resistor components)

54 ipc-6018b high frequency (microwave) printed circuit board

55 ipc-6901 IPC / JPCA brush electronic application classification

56 ipc-6903 t printed electronic Additional circuit) design and manufacturing terms
and definitions

57 design and assembly process implementation of ipc-7092 embedded components

58 design and assembly process implementation of ipc-7093 bottom terminal components (BTC)

59 design and assembly of ipc-7094 flip chip and chip level components
process implementation

60 ipc-7095 C BGA design and assembly process implementation

61 ipc-7251 PCB through-hole pad manufacturing standard

62 ipc-7525b template design guide

63 ipc-7526 template and misprint plate cleaning manual

64 ipc-7527 solder paste printing requirements

65 ipc-7530 Wave soldering reflow soldering process temperature curve guide

66 ipc-7535cn helps you effectively improve the tin slag

67 ipc-7711 / 21b ★ rework of electronic components

68 ipc-9121 PCB manufacturing process troubleshooting

69 ipc-9201 surface insulation resistance manual

70 Ipc-9252a unassembled PCB electrical test requirements

71 ipc-9261 is the DPMO process and estimated proction of PCAs

72 ipc-9592 power conversion equipment for computer and communication instry
requirements

73 ipc-9691a IPC-TM-650 test method 2.6.25 conctive anode wire (CAF) test (electrochemical migration test) User guide

74 ipc-9701a surface mount solder joint performance test method and qualification requirements

75 ipc-9702 plate interconnection unidirectional bending characteristics description

76 ipc-9704a PCB strain test guide

77 ipc-9708 qualification PCB assembly solder pad pitting test method Methods: 78 ipc-9851 SMEMA standard mechanical equipment interface standard

79 ipc-a-600h acceptability of printed circuit board

80 ipc-a-610f acceptability of electronic components

81 ipc-a-620b design and key process requirements Acceptance

ipc-a-630 ★ acceptability standards for manufacturing, inspection and testing of complete electronic procts

ipc-a-640 optical fiber Acceptance requirements for fiber optic cable and hybrid harness assemblies

82 ipc-aj-820 assembly and connection manual

83 ipc-cc-110a is a guide for selecting core buildings for multilayer printed circuit board applications, which is replaced by ipc-4121

84 identification and performance of electrical insulating compounds for ipc-cc-830b printed circuit board applications

85 IPC- Ch-65b PCB and components cleaning guide

86 ipc-d-279 high reliability surface mount PCB assembly technical design guide

87 ipc-d-371a electronic packaging design guide with high speed technology

88 ipc-hdbk-001 ★ j-std-001 supplementary manual and guide

89 ipc-hdbk-005 solder paste evaluation Evaluation guide

90 ipc-hdbk-610 ipc-a-610 manual and guide

91 ipc-hdbk-630 electronic procts complete machine manufacturing, inspection and testing acceptability standard manual

92 ipc-hdbk-830 conformal coating design Selection and Application guide

93 ipc-hdbk-840 solder mask manual

94 design of packaging materials and process for ipc-hdbk-850 PCB assembly Selection and Application guide

95 ipc-pe-740a PCB manufacturing and assembly troubleshooting

96 ipc-qe-605a PCB quality evaluation

97 ipc-s-816 surface mount technology process guide and checklist

98 ipc-sm-780 external mount component packaging and interconnection key points

99 Ipc-sm-782a component packaging standard

100 ipc-sm-785 surface mount weldment accelerated reliability test guide

101 ipc-sm-817a surface mount insulating adhesive general specification

102 ipc-sm-840e permanent solder resist and flexible covering material identification and performance specification

103 I Pc-spvc-wp-006 rotation test and analysis of lead-free alloy tin, silver and copper

104 ipc-t-50 electronic circuit interconnection and packaging terms and definitions

105 IPC-TM-650 ★ test method manual

Q buckle: 1395833280
contact me if necessary:

5.

Circuit breaker, contactor, intermediate relay, thermal relay, button, indicator light, universal transfer switch and travel switch are the eight most common components in electrical control circuit

Low voltage circuit breaker is also called automatic air switch, which can be turned on and off manually. It can also be used to distribute electric energy and start asynchronous motor infrequently to protect power line and motor. When they have serious overload, short circuit or undervoltage fault, it can cut off the power circuit automatically

Contactor is composed of electromagnetic mechanism and contact system. The most common coil voltage of contactor is AC220V, AC380V and dc220v

The electromagnetic mechanism of contactor is composed of coil, moving core and static core; The contact system of contactor consists of main contact and auxiliary contact. The main contact is used to make and break the main circuit, and the auxiliary contact is used in the control circuit

Thermal relay is a kind of relay which uses the principle of thermal effect proced by current passing through components to act in inverse time

Intermediate relay the principle of intermediate relay is to change an input signal into multiple output signals or amplify the signals. Its essence is voltage relay, but it has many contacts, contact capacity up to 5-10A and sensitive action

when the number of contacts of other electrical appliances is not enough, the number of contacts can be expanded by means of the intermediate relay, and the contact capacity can also be expanded by means of the intermediate relay

In practical application, buttons are usually selected according to the number of contacts required, the occasion of use and the color. The commonly used series of buttons, such as la18, la19 and la20, are suitable for Ac500V and dc440v, with rated current of 5A and control power of ac300w and dc70w

6. Indicator light

refers to the function of the light:

(1) indicates the operation or stop status of the equipment

(2) monitor whether the power supply of control appliance is normal

(3) the red light is used to monitor whether the trip circuit is normal, and the green light is used to monitor whether the closing circuit is normal

The universal transfer switch is composed of operating mechanism, panel, handle and several contact bases

Travel switch is a kind of position switch, which is a kind of commonly used low current master. Using the collision of the moving parts of the proction machinery to make the contact move to realize the connection or disconnection of the control circuit, to achieve a certain control purpose

6. B. Rapid increase

7. < DIV class=quote> In the new Audi A6 (four cylinder) car, the idle speed stabilizing device is integrated with the throttle Kr wi19 ^ R
control unit, which is installed in the box opposite to the cable, mainly including the throttle R) B} g
potentiometer g69, throttle control potentiometer G127 and idle speed switch Cm@UJ7p1e
F60 and throttle controller V60 (motor) and other components. BqYS*SV*' 4
it should be noted that all potentiometers and switches can not be adjusted mechanically, D & # 39& Vt::
can only be completed with the help of the basic adjustment function of the decoder of the car computer; I & M
success. NW '^' ^, &
specific operation method. Throttle control unit and engine control unit adjust o&# 39; s. @} n
in order for the engine idle speed stabilizer to work, the engine control unit must know the dead center position of (85alm /
throttle controller V60. At the same time, we also need to know the throttle control system; NN
sensor G127 and throttle potentiometer g69. Usually, when replacing the throttle control ujpgg? X '& quot
it is necessary to adjust the control unit or engine control unit, such as [HEWL & # 92; GB
below: YCN,; FZN
(1) connect the computer decoder and turn on the ignition switch; N +} P, H
(2) select the engine system and press the [OK] key; T9>+ SUV} at
(3) select the basic adjustment function and press [OK];: P; Y0wc
% yfojyu
(4) enter group number 098 and press [OK]. W8> S' ^ qsvn
after pressing the [OK] key, the basic adjustment process starts and the throttle controller runs to M_& J7dgi
maximum, minimum and middle opening. Engine control unit in memory + tkny #, #, 39^ R
several throttle angles are counted in the reservoir, and then the throttle is kept in the start position for a short time, fflx {k = F & lt; br/> Set and then close= PDTxXg(6 < br/> There is a possibility that the basic adjustment of the throttle control unit may be interrupted&_ Imcpa}
the main reasons for these cases are: the throttle can not be completely closed (such as dirty throttle body, soeyis V
dirty), improper adjustment of throttle cable, too low battery voltage, throttle control unit $, BT
or wire damage, starting the engine or stepping down the accelerator pedal in the adaptive process. After i9rmb8os
interruption, the fault memory will store the information of "basic adjustment not completed, basic adjustment 1x 8 & TKU
error". The next time the ignition switch is turned on, the basic adjustment will automatically enter% Doo} kg
line again. KV + C ^ J ~
idle switch check: the specific operation steps are as follows:` e@dEx
(1) connect the car computer decoder and turn on the ignition switch@ c t\
(2) select the engine system and press the [OK] key; f.h5CxI!
(3) select the read measurement data block function and press the [OK] key; I61L$' Nzxb
(4) input group number 098 and press [OK]. U+5W\ J!%
display area 3 should display idling, open slowly and then close, CDW & x [
throttle, and display area 3 should jump from "partial compliance" to "idle". If BB ad * 8 +
does not appear the above situation, it is necessary to unplug the throttle control unit plug and check whether the lead wire H% v3w ` MX +
is short circuited or open circuited to the positive pole. If the lead wire has no fault, it is necessary to check whether the throttle is dirty or flexible, and then match the throttle control unit (operation%] J. & lt; z"{ 9 < br/> The process is described above. If the basic adjustment process of the throttle control unit cannot start eedtxg & lt; br/> If it can't be finished, the throttle cable can be removed, and then the throttle control W ~ B & gt; can be performed again* WS < br/> Basic adjustment of the unit; If the basic adjustment of the control unit cannot be completed, it should be more @ NEA& gt; ZjH < br/> Replace the throttle control unit. 1& `:Q^8 < br/> Check of throttle potentiometer: the function of throttle potentiometer is to control the engine? f\| FRYP" & lt; br/> In the control unit, the throttle position signal is sent to check the specific operation of the throttle potentiometer; iIO & < br/> It is as follows:} syh ~ FD (# 92; J
(1) connect the computer decoder and turn on the ignition switch; Pjiel - $m
(2) select the engine system and press the [OK] key; X1f6ns5m
(3) select the function of reading measurement data block and press the [OK] key; 0> SW {$x
(4) enter group number 001 and press [OK]. E. @ | 8N [
check the display area 3, the specified value should be 0-5 °， Then slowly press the accelerator pedal} EMT - ia
to the end, and the display value of display area 3 should increase steadily, and finally reach 85-90 ° Between+ Z | m) @
if the initial value and the specified value do not meet the requirements, check the throttle control unit; 5cjr8u
voltage; If the displayed value remains unchanged or changes irregularly, check the wire connection# Udbwqt $t
check of throttle control sensor; Iknme (s
the function of the throttle control sensor is to send the throttle jhi = * & (
the position signal of the gate controller (V60). Check the details of throttle control sensor; WZ ` 4E
the operation is as follows: Q @ &
(1) connect the computer decoder and turn on the ignition switch; (2) select the engine system and press the [OK] key; B ~ aw QM -
(3) select the function of reading measurement data block and press the [OK] key; xXRK!=] XGC
(4) input group number 098 and press [OK]; { Um? U $
the specified value of display area 2 is 0.500-4.900 v. if the specified value is not reached, hycf * & quot+ D
the plug of throttle control unit should be pulled off and the resistance between wires should be detected. The maximum value should not exceed [& lt` D {7
1.5 Ω If the wiring is OK, replace the throttle control unit & lt/ DIV>

9.

Python language used by alphago is the programming language closest to AI

the examination center of the Ministry of Ecation recently issued a notice on the adjustment of the national computer rating system (NCRE), and decided to add the subject of "Python language programming" to the national computer level II Examination from March 2018

nine months ago, the information technology curriculum reform plan of Zhejiang Province has been issued, and Python is determined to enter the information technology textbook of Zhejiang Province. From 2018, the programming language of information technology textbook of Zhejiang Province will be changed from VB to python

primary school students have begun to learn python. My God, it's right to read all this

Amway Yibo book list

Introction to Python

Python data analysis

Author: [Indonesia] Ivan Idris

Python is a multi paradigm programming language, which is suitable for both object-oriented application development and functional design pattern. Python has become an ideal programming language for data scientists to carry out data analysis, visualization and machine learning. It can help you quickly improve your work efficiency

this book will lead novices familiar with all aspects of Python data analysis related fields, from data retrieval, cleaning, operation, visualization, storage to advanced analysis and modeling. At the same time, this book focuses on a series of open source Python moles, such as numpy, SciPy, Matplotlib, panda, IPython, python, scikit learn and nltk. In addition, the book also introces data visualization, signal processing, time series analysis, database, predictive analysis and machine learning. By reading this book, you will become a master of data analysis