Commodity price indexing by HS code

List of the catalog of this article:

• 1,Commodity price indexing by HS code Design in pure C language (no C++)Bus card management system
• 2, Why do buses in big cities use rear engines
• 3, Who designed theA set of urban public transportation system
• 4, System design of intelligent bus

Design bus card management system in pure C language (no C++)

1. Generally IC The machine has a corresponding server, and the server stores data.. Therefore, you only need to consider reading the data in the IC database. Other work is done by the IC machine by itself.The problem of designing the interface. The specifics also lee on the parameters of the manufacturer.

2. Develop a book information management system, which includes: book number, book title, author, publisher, category, publication time, price and other basic information.

3. A large-scale sports meeting needs a management system to unify the management of all participating athletes and their achievements. This topic requires the design of a sports management system in C language, which can add, delete and modify athletes' achievements, and realize various statistical functions.

4. Widely used: C language is widely used in system development, embedded system, game development, network communication and other fields. For example, Linux operating system, MySQL database management system, etc. are all written in C language.In addition, C language is also the basis of many advanced programming languages (such as C++, Python, etc.).

Why do buses in big cities use rear engines

The vast majority of large buses are rear-wheel drive. Now the rear of the engine is because it can minimize the casualty rate of drivers and passengers in the event of an accident, and it can also improve the space utilization rate; however, the disadvantage is that it does increase the probability of engine maintenance in the event of a rear-end accident.

Nowadays, large buses basically use rear engines. The original front engine is noisy, which is not conducive to the convenience of front door passengers, and the transmission shaft runs through the car body, affecting the ground in the car. The biggest advantage of the rear engine is that this kind of vehicle has compact powertrain, good mobility, and small quality of the whole vehicle.

For passenger cars, the rear engine can make the power transmission distance much shorter, more efficient, and can do better sound insulation (recall the noise of old buses and airport shuttles).

The first reason is that the engine of the bus is designed to be rear, which can make room for the front of the car and lower the height of the cockpit, thus reducing the driver's blind spot. Assuming that the engine of the bus is front-mounted, the huge engine and its accessory equipment will occupy a lot of the front of the bus, which will raise the position of the driver's cockpit.

The most important thing is that the passenger car engine is rear-end, because people have this demand, and the chassis of the large truck is very complete, and there is no new design that needs to put the engine at the rear of the car. The heat dissipation of the rear engine is a big problem.The radiator of the front engine is located at the front of the car.

Therefore, large buses are very popular in the form of rear-engine rear-wheel drive.

Who designed the first urban public transportation system

In the year, the British Pearson designed the world's earliest urban subway system for the city of London. For various reasons, the British Parliament did not approve it until 10 years later. A subway less than 6 kilometers long was built between Lynton and Bishop Road. After nearly ten years of construction, the subway has begun to take shape.

Urban public transportation system refers to an organic whole composed of a variety of urban public transportation modes. Urban public transportation first appeared in the United Kingdom. In 1829, the first horse-type public transport appeared in London, England.The common carriage has a history of more than 160 years, during which it has experienced the stage of development, prosperity, decline and the current revival.

Subway is a fast, large-volume and electrically driven rail transportation built in cities. The subway is a proprietary, high-density and high-volume urban rail transit system that covers all kinds of underground and above-ground rights of way in urban areas. The earliest (and first) subway in the world was the Metropolitan Underground in London, England, which was built in 1863.

Rail transit refers to a kind of transportation or transportation system that operates vehicles that need to travel on a specific track. The development history of urban rail transit is as old as that of railways, and it has risen and declined with the rise and expansion of cities.

The existing urban road network in China is generally low-density, the spacing of trunk roads is too large, andThere is a shortage of roads and chaotic functions. It is a low-speed transportation system, which is difficult to adapt to the needs of modern automobile traffic, which hinders the realization of automobileization in cities.

System design of intelligent public transportation

Design and research on the design of public transportation system suitable for the elderly in smart city Chapter 1 Building intelligence Public transportation for the elderly in Huicheng CityThe system includes not only the physical product design of "tangible products", but also the symbolic design of "intangible products" and the interactive design of "information products".

Resource integration should organize more exchange meetings between equipment manufacturers and relevant industry personnel such as design institutes. The design unit should put forward requirements and guide manufacturers to produce products. Manufacturers push good products to the design unit, and the design unit applies them in practice.

The importance of intelligent transportation system architecture is to alleviate traffic congestion, improve transportation efficiency and improve transportation safety. The details are as follows: Alleviate traffic congestion: With the increase of urban population and the increase in car ownership, the problem of traffic congestion is becoming more and more serious.