According to legend, China's New Year's Day originated from Zhuan Xu, one of the Three Sovereigns and Five Emperors, and has a history of more than 3,000 years. The word "New Year's Day" first appeared in the "Book of Jin": "Emperor Zhuan took the first month of Mengxia as the Yuan Dynasty, which is actually the spring of New Year's Day in Zhengshuo". During the Northern and Southern Dynasties, Xiao Ziyun's poem "Jie Ya" in the Southern Dynasties also recorded that "New Year's Day for all four seasons, early spring for longevity". China was the first to call the first day of the first lunar month "New Year's Day". Yuan means "beginning" and "beginning", and dan refers to "days". New Year's Day collectively refers to the "initial days", which is the first day of the year. The date on which the first day of the first lunar month was calculated was also very inconsistent before Emperor Wu of the Han Dynasty. Therefore, the month and day of New Year's Day in the past dynasties are not consistent. The lunar calendar of the Xia Dynasty took Meng Xi month (Yuan month) as the first month, the Yin calendar of the Shang dynasty took the twelfth month (December) as the first month, and the Zhou calendar of the Zhou dynasty took the winter month (November) as the first month. After Qin Shihuang unified China, he took Yangchun month (October) as the first month, that is, the first day of October as New Year's Day. Starting from Emperor Wu of the Han Dynasty, Meng Xiyue (January) was designated as the first month, and the first day of Meng Xiyue (the first day of the first lunar month in the lunar calendar) was called New Year's Day, which was still used until the end of the Qing Dynasty. But this is the lunar calendar, that is, the lunar calendar or the lunar calendar, and it is not what we call New Year's Day today. In 1911 AD, the Revolution of 1911 led by Sun Yat-sen overthrew the rule of the Qing Dynasty and established the Republic of China. In order to "make Xia Zhengzheng, so it follows the agricultural time, and it is based on the Western calendar, so it is convenient for statistics", it was decided to use the Gregorian calendar in the first year of the Republic of China (actually used in 1912), and stipulated that January 1 of the Gregorian calendar (Gregorian calendar) was the "New Year", but it was not It's called "New Year's Day". What we call "New Year's Day" today is September 27, 1949. The first plenary session of the Chinese People's Political Consultative Conference decided to establish the People's Republic of China. It also decided to adopt the world's common AD calendar and change the Gregorian calendar to January 1st is officially designated as "New Year's Day", and the first day of the first lunar month is changed to "Spring Festival".

The twenty-four solar terms are twenty-four solar terms that reflect the seasonal characteristics of natural phenomena and agricultural activities in a year. That is, Beginning of Spring, Rain, Jingzhe, Vernal Equinox, Qingming, Grain Rain, Beginning of Summer, Xiaoman, Ear Grain, Summer Solstice, Minor Heat, Major Heat, Beginning of Autumn, End of Heat, White Dew, Autumnal Equinox, Cold Dew, Frost Descent, Beginning of Winter, Light Snow, Heavy Snow, Winter Solstice, Minor Cold, and Major Cold. The twenty-four solar terms are based on the solar calendar. According to the position of the sun on the ecliptic, starting from 0° of the ecliptic longitude, every 15° is a section. There is one "middle energy" and one "solar term" every month, and the whole year is divided into ten. The two "Zhong Qi" and the twelve "solar terms" will be collectively referred to as solar terms from now on, with a total of twenty-four solar terms. Names with distinctive meanings are given based on astronomical, climatic and agricultural production seasons. The twenty-four solar terms are a unique creation of ancient China, originating from the middle and lower reaches of the Yellow River. It takes the climate of the Yellow River Basin as the background and combines natural seasonal phenomena with agricultural production activities as the content. The vernal and autumnal equinoxes represent the equinox of day and night and a moderate climate; The summer solstice and winter solstice signify the arrival of summer and cold winter respectively; The beginning of spring, the beginning of summer, the beginning of autumn and the beginning of winter respectively represent the beginning of the four seasons of spring, summer, autumn and winter; Rain indicates the beginning of the rainfall season; Jingzhe is when hibernating animals begin to revive and wait for emergence; Qingming means that the weather is getting warmer, the grass and trees are new and green, and the scenery is fresh; Grain Rain is when rainfall begins to increase, which is beneficial to grain growth; Xiaoman means that the grass and trees are beginning to flourish, and the grains of summer-ripened grains are beginning to be full; Eargrass is a busy time of year for farming, and summer harvesting, summer management, and summer planting need to be carried out in a timely manner; Minor Heat and Major Heat are the hottest seasons of the year; Sushu means the end of the hot season; White dew means that the temperature has dropped, the humidity is still high, and there is a lot of dew; Cold dew means that the ground radiation cools quickly and the condensed dew has a low temperature; Frostfall means that the weather is getting colder and frost begins to form; Light snow and heavy snow indicate the beginning of snowfall season; Xiaohan and Dahan are the coldest seasons of the year.

On October 1, 1949, the founding ceremony of the Central People's Government of the People's Republic of China, that is, the founding ceremony, was grandly held in Tiananmen Square in Beijing. "The first person to propose the 'National Day' was Mr. Ma Xulun, then a member of the CPPCC and chief representative of the Democratic Progress Party." On October 9, 1949, the first National Committee of the Chinese People's Political Consultative Conference held its first session. Member Xu Guangping spoke :" Ma Xulun can not come on leave, he asked me to say that the establishment of the People's Republic of China, there should be a National Day, so I hope this Council will decide to set October 1 as the National Day." Member LAM Pok Yuen also spoke and seconded the motion, requesting discussion on the decision. On the same day, the meeting passed the proposal of "asking the government to specify October 1 as the National Day of the People's Republic of China to replace the old National Day on October 10" and sent the Central People's Government to adopt and implement. On December 2, 1949, the resolution adopted at the fourth meeting of the Committee of the Central People's Government stated :" The Committee of the Central People's Government hereby declares that, since 1950, October 1 of each year, that is, the great day on which the People's Republic of China was proclaimed, shall be the National Day of the People's Republic of China." This is why "October 1" was identified as the "birthday" of the People's Republic of China, that is, the "National Day". Since 1950, October 1 every year has become a grand celebration of the Chinese people of all ethnic groups. In the early days of the founding of New China (1950-1959), large-scale celebrations and military parades were held every year on the National Day. In September 1960, the CPC Central Committee and The State Council decided to reform the National Day system in line with the principle of building a nation through diligence and thrift. Since then, from 1960 to 1970, grand rallies and mass parades have been held in front of Tiananmen Square every year on National Day, but no military parade has been held. From 1971 to 1983, every year on October 1, Beijing celebrated the National Day with large-scale garden party activities and other forms, without mass parades. In 1984, the 35th anniversary of the National Day, held a grand National Day parade and mass celebration parade. In the following ten years, the National Day was celebrated in other forms, and no National Day parade and mass celebration parade were held. On October 1, 1999, the 50th anniversary of the National Day, a grand National Day parade and mass celebration parade were held. This was the last grand National Day celebration held by the People's Republic of China in the 20th century. The National Day of the People's Republic of China is a symbol of the country, which appears with the emergence of the country and becomes particularly impor...

An excavator is a construction vehicle used to dig or move large objects.It is made up of two parts:a driving base and a powerful boom arm with an attachment desigined for digging.The operator sits inside a small cab attached to the base and controls the arm. The base has two sets of articulating tracks that are attached to the side of the excavator.The tracks oprater like wheel to move the unit,but provide a large surface area that creates in a more stable base for the machine.On top of the base is a plarform that rotates between 180° and 360°. The opetator sits inside the cab and has two sets and controls.One sets moves the actual unit forward and backward,and the other set moves the unit on the horizontal plan and controls the arm.These controls determine the angle and speed of the movements of the arm and bucket along the vertical axis. An excavator is designed foe use on construction sites and is quite expensive to purchase.Many smaller construction companies lease or rent these units to avoid the expensive overhead costs.The lease and rental rates vary,depending on the length of the contract,and the volume of the business with the leasing firm.The more equipment that a company leases or rents from the same firm,the better the pircing will be. All oprators are required to obtain a license for the safe operation of this machine.Failure to obtain this qualification can result in a construction site being closed by the workplace health and safety inspector until a valid certificate holder is available to operate the equipment.In addition,many insurance policies are void if the equioment is not operator. Excavators come in a wide range of sizes and capacities,and the heavier the unit,the greater the lift capacity will be.Some are small enough to fit through a standard doorway,while others are much larger.The most important factor for a person to consider when looking at smaller excavators is the amount of workgroup movement.The greater the degree of the move.

TRACK ROLLER The purpose of track roller is to transfer the weight of the chain to the ground and roll on the tracks.In order to prevent derailment,track roller  should also prevent the track from moving horizontally relative to it. Track roller often works in mud,water and sand,and bears strong impact,the working conditions are extremely bad,the rim is easy to wear. The requirements of the support wheel are:wear resistant rim,reliable bearing seal,small rolling resistance and so on. CARRIER ROLLER The functon of carrier roller is to keep the chain track in a straight line.If the carrier roller is damaged,the track chain track cannot keep the straight line. Carrier roller is a one-time injection of lubricating oil,if there is oil leakage can only be replaced,in the work should try to aviod supporting wheel long time immersion in muddy water. SPROCKET The sprocket is a transfer force,can change the speed of rotation,can change the direction of rotation. IDLER The excavator front idler is used to guide the track to turn correctly to prevent it of running of track and deviating.Most excavators also play the role of a heavy wheel. In this way,the contact area between track and ground can be increased and the specific grounding pressure can be reduced. The wheel surface of the guide wheel is made of smooth surface,and there is baffle ring in the middle as a guide,and the torus on both sides supports the rail chain. TRACK CHAIN The tightness of excavator track is is like the size of shoes worn by pepole,which must be adjuster to the best state to move forward.In the working operation of excavator. It often causes the change of crawler's tightness,and the tightness of crawler also determines the wear degree of the chain to its contact accessories. TRACK CHAIN ASSEMBLY The track chain assembly is composed of two parts:the track shoe and track chain,and the two parts are joined together by bolts and buts.

There are many forms of industrial equipment used in the workplace. Industrial equipment is usually large and made of materials such as steel and titanium for optimal strength. These machines are often needed to lift and move materials which may possibly weigh thousands of pounds. A piece of industrial equipment which is not in working order should never be used for any reason. All equipment is inspected at the beginning of everyday to ensure they are in the best condition for workers. By now, there are a million pieces of industrial equipment racing through your head but the question is, which ones are the most popular and most crucial to the industrial field? Below you will find five types of industrial equipment which are known to be the masters of all machines in the industrial workplace: Bulldozers - Bulldozers are massive machines which are used mostly in the construction and mining industries. Bulldozers have the ability to lift and move vast amounts of dirt and other debris from one place to another. Bulldozers can operate in many conditions including snow, hail and rain. These pieces of equipment are generally used to dig up the ground and provide room for building houses or other types of buildings. Cranes - Cranes are generally used to transport hard, heavy items from one place to another. The arm of the crane is used to swing the object from one place to another and the arm can be adjusted according to how far the materials need to go. Unlike bulldozers, cranes have the ability to transport objects over uneven levels of ground. Excavators - Excavators are engineering vehicles which consist of backhoes and cabs. They are mainly used in the digging of trenches, foundations and holes. They can also be used to destroy objects which are no longer needed for any reason and in which case need to be compressed and condensed. Fork Lifts - Forklifts are warehouse vehicles which are used to lift, hoist and transport extremely heavy items from one place to another. Forklifts are known to be indispensable pieces of equipment in many industrial workplaces. Compressors - Most of the pieces of equipment listed above are used for construction purposes, however compressors are generally used in more of a factory-type setting. Compressors are used to provide high pressures of air or other forms of gases. These devices can be regulated in order to maintain the desired amount of pressure in the tank. There are many other forms of industrial equipment. Each piece of equipment is designed to perform a specific task which contributes to the overall success in this field of work. Without these forms of equipment many industrial areas would not exist.