Announcement of winning the bid for the main theater stage sound (Phase I) project of the renovation and renovation project of Beijing Workers’ Club and affiliated buildings

I. ProjectNo.: BJJQ-2024-1077(Bidding DocumentNo.: BJJQ-2024-1077)

II. Project Name: The main theater stage sound (Phase I) project of renovation and renovation project of Beijing Workers’ Club and affiliated buildings.

Third, the winning bid (transaction) information

Name of supplier: Beijing Renge Technology Co., Ltd.

Supplier Address: Room 5B01, Floor 4, Building 78, East Fourth Ring Road, Chaoyang District, Beijing

Winning bid (transaction) amount: 4,089,6000 yuan (ten thousand yuan)

Fourth, the main target information

serial number    Supplier name      description of goods      Brand of goods      Model of goods      Quantity of goods      Unit price of goods (yuan)   one    Beijing renge technology co., ltd      The renovation project of Beijing Workers’ Club and its affiliated buildings: Stage Sound of the Main Theater (Phase I)      See attachment      See attachment      See attachment      See attachment                

V. List of evaluation experts (single source procurement personnel):

郝寅祥、杨平、武俊玲、孟青、孙彤宇、高印柱、郭淳

六、代理服务收费标准及金额:

本项目代理费收费标准:详见招标文件

本项目代理费总金额:3.177425 万元(人民币)

七、公告期限

自本公告发布之日起1个工作日。

八、其它补充事宜

8.1本公告在中国政府采购网(http://www.ccgp.gov.cn)、中国招标投标公共服务平台(http://www.cebpubservice.com/)上发布。
8.2中标人综合得分:96.64。 

 

九、凡对本次公告内容提出询问,请按以下方式联系。

1.采购人信息

名 称:北京市劳动人民文化宫     

地址:北京市东城区天安门东侧        

联系方式:张老师,010-63557718、63530888      

2.采购代理机构信息

名 称:北京汇诚金桥国际招标咨询有限公司            

地 址:北京市东城区朝内大街南竹杆胡同6号北京INN3号楼9层            

联系方式:李雅琪、苑鑫,010-65244468、65170699            

3.项目联系方式

项目联系人:李雅琪、苑鑫

电 话:  010-65244468、65170699

 

A detailed explanation of "nucleic acid vaccine"

This article is the original article of Kanjian Daily for the health sector. For more in-depth articles, please click: Kanjian Daily.

With the promotion of vaccination in COVID-19, many people have received vaccination notices one after another and made an appointment to vaccinate COVID-19 vaccine. But at the same time of vaccination, many people also questioned: what is the vaccine we are playing? Does it really work?In fact, there are many kinds of vaccines in Covid-19, including inactivated vaccine, adenovirus vector vaccine and mRNA vaccine, as well as COVID-19 vaccines such as recombinant subunit, synthetic peptides and DNA. Each vaccine has different ways and advantages.

Inactivated vaccine is the "base"

Inactivated vaccine is the most traditional vaccine preparation method. Inactivated vaccine can be simply understood as that by injecting artificially inactivated pathogenic microorganisms or their metabolites (antigens) into the body, the human body can recognize the antigens to produce specific antibodies. Once invaded by external specific viruses, these specific antibodies will mediate the body’s defense function and thus resist the invasion of viruses.

Inactivated vaccine is a mature technology, and its safety is good, but the production cycle is long (more than 60 days), and its immunogenicity becomes weak, so it needs multiple immunizations to strengthen the curative effect. Inactivated vaccines on the market include: Japanese encephalitis inactivated vaccine, hepatitis A inactivated vaccine, rabies vaccine, cholera vaccine, etc., which can be said to be widely used.

Figure 1: Inactivated vaccine (from IMMUNOLOGY.org)

COVID-19 inactivated vaccine, which contains inactivated virus SARS-CoV-2, still retains some antigenicity, but it will not cause the vaccinator to be infected with COVID-19; It can be recognized by the immune system and activate the immune response.After the successful establishment of immune memory, the immune system of the vaccinated person will have immune resistance to Covid-19 in the future. At present, Sinovac Kexing Bio, Sinopharm Chinese Medicine and COVID-19 Vaccine from Bharat Biotechnology are all inactivated vaccines.

However, due to the lack of activity, long production cycle and low vector conversion rate of inactivated vaccine, many countries have begun to develop the latest vaccine types …

Table 1: Some clinical trials of COVID-19 vaccine under study [1]

The development of nucleic acid vaccine is "the general trend"

As a newly emerging biological product at the gene level, nucleic acid vaccine plays a vital role in the prevention and control of many diseases such as bacteria, viruses, parasites and tumors.In recent years, with the emergence of various new diseases, the disadvantages of traditional vaccines are gradually exposed, which can no longer meet people’s needs. Traditional vaccines, such as attenuated vaccines and inactivated vaccines, are generally transformed by vectors, and their immune efficiency is low. Studies have found that attenuated vaccines may also have toxic residues, which may lead to the risk of secondary infection. As a new vaccine, nucleic acid vaccine can activate the immune mechanism of the body through specific channels, thus achieving the effect of rapid immunization, which is safer and more efficient than traditional vaccines [2].

Nucleic acid vaccines are mainly divided into DNA vaccines and RNA vaccines. DNA-based vaccines are mostly used in tumors, while the new COVID-19 vaccines currently under development are mostly mRNA-based vaccines. The inoculation method of nucleic acid vaccine and the regulation of influencing factors have great influence on inducing the expression of antigen protein in the body, especially the selection of promoter and vector. In addition, there are various inoculation methods of nucleic acid vaccine, and choosing the appropriate inoculation route of nucleic acid vaccine will help to improve the transformation rate of vaccine. In the future, nucleic acid vaccine will become an indispensable biological product in the fields of human disease prevention and treatment, and has broad application prospects.

Table 2: Some nucleic acid vaccines under research for tumors (compiled by the author)

MRNA vaccine is expected to become a "hard-core" vaccine against COVID-19 mutation quickly.

Essentially, a nucleic acid vaccine is to inject a plasmid vector with a specific pathogenic microorganism foreign antigen coding gene (mostly DNA) sequence into a specific host cell. Under the control of the vector plasmid, the foreign antigen gene is transcribed into a specific antigenic mRNA (this process usually requires the participation of a strong promoter), and a functional protein is generated through a series of signal transmission to activate the immune response.

At present, many vaccines developed by COVID-19 vaccine research and development companies are mRNA vaccines, and mRNA vaccines have obvious advantages compared with inactivated vaccines..Firstly, because mRNA vaccine does not depend on cell amplification, its detection and quality control are relatively simple. Secondly, the speed of vaccine production is also very important for the current situation because it saves the time of cell culture and expansion and greatly improves the vaccine productivity. At present, as the third generation vaccine technology, mRNA vaccine is a technical route vaccine used by many western developed countries. MRNA vaccine can accurately express antigen and activate the dual immune mechanism of "body fluid +T cells", which has strong immunogenicity and does not need adjuvant.

Figure 2: Overview of nucleic acid vaccine in COVID-19 (from IMMUNOLOGY.org)

It is worth noting that on April 6th, 2021, the top medical journal, the New England Journal of Medicine (NEJM), published a communication article from the National Institutes of Health (NIH), reporting the antibody attenuation after 6 months of inoculation with mRNA COVID-19 vaccine (mRNA-1273).

Figure 3: Anti-body persistence through 6 months after the second dose of mRNA-1273 vacuum forcovid-19

In this study, the serum of 33 patients inoculated with two doses of mRNA-1273 was analyzed. Through two neutralization test methods, pseudovirus neutralization test and live virus FRNT test, it was found that the serum neutralization activity of mRNA-1273 vaccinators of all ages continued at ID50100 and above for up to 6 months after vaccination. It can be seen from the curve in the study that the neutralization activity of mRNA-1273 reached the peak 7 days after the second inoculation.

Table 3: Time course of SARS-CoV-2 antibody binding and neutralization reaction after 3:mRNA-1273 vaccination

From the kinetic curve of antibody metabolism provided by this study, it can be seen that the serum neutralizing antibody level is very stable after inoculation with mRNA-1273, and the antibody activity in all age groups remains at a high level on the 209th day of inoculation. Moreover, this result has been verified in three different types of tests. It should be noted that the antibody level does decrease with age.

Write it at the end

Based on the advantages of mRNA vaccine, the World Health Organization (WHO) has approved the urgent use of mRNA vaccine. At present, 68 countries and regions including the United States, Britain, China and Hongkong have introduced mRNA vaccine. But even if the mRNA vaccine is so superior, there are still many disadvantages.

First of all, from the principle of action, when the mRNA vaccine is injected into the host, there is a certain chance that the foreign antigen sequence fragment will be mistakenly integrated into the genome of the organism, causing the disease of the organism [2]. Secondly, from the technical point of view, RNA itself is unstable, and mRNA is likely to be degraded when it enters the body, so it needs to be delivered by additional vectors. In addition, transportation and storage may require very strict and low temperature conditions, which will be a great challenge in research and development.

However, it is undeniable that in the clinical trial reports of various mRNA vaccines, the antibodies produced by them can be maintained in the body for at least 6 months. Some experts believe: "With the research on antibodies and other related factors of immunity after vaccination in COVID-19, it is expected that we will observe that immunity will last for a longer time [4]." It can be predicted that mRNA vaccine represents the world’s leading nucleic acid vaccine route, and together with the traditional technical route vaccine, it will form a joint phalanx of vaccine research and development, which will bring dawn to the decisive victory of global anti-epidemic.

References:

1. Xing Kai, etal., systematic evaluation of the efficacy and safety of COVID-19 vaccine. China Journal of Contemporary Pediatrics, 2021.23 (03): P.221-228.

2. Li Wei, Cao Wenjing, and Cheng Yongxiang, the latest research progress of nucleic acid vaccine. Contemporary Animal Husbandry, 2020 (09): P.16-19.

3.Doria-Rose,N.,etal.,Anti body Persistence through 6 Month safter the Second Dose of mRNA-1273 Vaccine for Covid-19.NEnglJMed,2021.

4. How long will COVID-19 vaccine "work" from a new medical perspective? NEJM publishes data on the persistence of mRNA vaccine protection. New medical perspectives, 2021.

Welcome to submit good articles on medical health. After employment, the remuneration is rich, and priority is given to the promotion of the whole platform in the health sector.

Please send the manuscript to: wangdandan@hmkx.cn

1 million takeaway riders: the struggle and hope in 100,000 short videos.

Every morning and evening rush hour or weekend, the surrounding area of Chaoyang Joy City is always full of traffic. The residential areas and office buildings here are connected together, gathering a large number of fashion brands and creative restaurants, which is not only the punching place for trendy people and foodies in Beijing, but also the regional "base camp" for takeaway brothers.

One by one, waiting beside the electric take-away cars on the roadside, the riders who have taken orders are in a hurry. They go in and out of various restaurants, and the lunch boxes in their hands may be freshly baked restaurant specialties, coffee, ice cream or midnight snack.

Chaoyang Joy City is just a microcosm of the take-away market. According to the report of iResearch, there are more and more young people and office workers in China who are willing to spend money on convenience. After five years, the online penetration rate of food consumption will reach 29.5%, which is about 14.1 trillion yuan.

Behind the busy riders is the protracted battlefield of the giants. After numerous melee, killing and subsidy wars, this year, Meituan Dianping finally went public as the world’s largest food and beverage delivery service provider and the largest in-store food and beverage service platform in China. However, Ali was hungry after integration, and Enemy at the Gates.

This year, in order to achieve the goal of gaining 50% share of the take-away market, Ali took out nearly three times the subsidy of the US delegation, and claimed that there was no upper limit for the recruitment of riders.

The ultimate battle around "eating" is underway. In addition to the first-tier cities such as Beishangguangshen and Shenzhen, the war is about to spread to more cities and counties in Ali and Meituan.

In the new retail industry logistics system that pursues efficiency and speed, the rider is the most basic element, and it is also an important link in the increasingly refined life industry chain. In the world of short video, riders, as individuals with emotions, are like detectors, reflecting the changes of the whole market, the vibration of industry and the transformation of society.

From factory to takeaway

Every year, Meituan Review publishes an "Annual Report on Takeaway Development". In the report, the daily average number of active distribution riders of the US Mission increased from 100,000 in 2015 to 531,000 in 2017.

According to the statistics of "Research Report on Takeaway Riders in 2018", 75% of riders come from rural areas, and nearly 70% of riders choose to leave their hometown to work hard in other places and struggle in first-and second-tier cities. Moreover, young people after 1980s and 1990s account for 82% of the riders.

In just three years, take-away riders have changed from marginal jobs to "reliable" jobs for young rural laborers in cities. The comments of the US delegation and Hungry have created more than one million jobs, and the work of "Lingzhi Xiaoxiao" belongs to this "one in a million".

At the beginning of this year, a 21-year-old Dong girl came to Hangzhou from her hometown of Yunnan. A friend introduced her to work in a clothing factory where many fellow villagers worked. In a workshop full of girls, she kept cutting clothes and car lines from morning till night. The first month’s salary was 2,800 yuan, the second month was 2,500 yuan, and the third month found that the salary was too low. She only worked for half a month and resigned after taking 1,500 yuan.

Later, she went to work in a restaurant. I heard from a familiar rider that Meituan crowdsourced her working hours flexibly and made more money, so she wanted to try it part-time. Unexpectedly, she found a sense of belonging in this man’s industry.

"When I arrived at the US Mission, I felt that I had been mixed up before." Novel, in the past, in the clothing factory, peers always wanted to eat, wear and play. After becoming a rider, I saw that my fellow riders were racing against time to make money, and the realistic pressure of "getting married and saving money" made her mature at once.

Unlike the assembly line in the factory, the rider needs a strong "motive force". Because part-time riders have no basic salary and earn as much as they do, the real-time income of sending a few dollars makes her very economical and punctual. Short stories, those riders who earn more than 10,000 yuan a month are very hard-working, running for 15 hours every day, and often finishing work at 3 or 4 in the morning. These role models make her even reluctant to talk about her boyfriend, because time is too precious and she is afraid it will cost too much money.

Xiaoxiao also found himself "more and more tough." I remember that in the first week as a rider, the delivery road was bumpy at 11 o’clock at night. Some soup spilled on the bag, and the customer looked ugly and slammed the door. She cried sadly, thinking about "bad reviews" and "I didn’t mean to". At that time, she took a video to record an unfortunate day. As a result, fans in Aauto Quicker left messages to cheer her up, and riders left messages to teach her how to deliver a soup meal and how to appease unhappy customers.

However, Xiaoxiao is afraid to tell her family that she is running a takeaway, because a little girl who works as a rider always makes people worry. She said that if there is no income from live broadcast on Aauto Quicker, she will often deliver meals until the early hours of the morning, which is the normal state of crowdsourcing riders.

In the past six months as a rider, Xiaoxiao recorded the ups and downs of being alone in a foreign land on Aauto Quicker in the form of short video, which is also her way to fight loneliness and pressure. She said that although there are only 14,000 fans, chatting with them live every night after work, and the fatigue and grievances of work have vanished.

Although she is not as stable as her fellow villagers, Xiaoxiao is not very satisfied with her job. She can earn four or five thousand yuan by delivering food every month, and her income is several times that of a girl from her hometown.

As shown in the World Development Report 2019: Changes in the Nature of Work released by the World Bank, technological progress has accelerated the growth of platform enterprises, and is also changing the way people work, creating more non-traditional jobs and short-term "odd jobs". From the small description, we can intuitively feel that the young labor force is shifting from the traditional agricultural and manufacturing fields to the service industry, and correspondingly, it will also accelerate the rapid development of local life business.

From the third and fourth lines to the first and second lines.

In July this year, Hungry announced that it had invested RMB 3 billion in the "Summer Campaign", and what this data shows is the way to attract cooperative large, medium and small businesses and riders and incite the take-away market.

Abo can list the policies such as unit price, rewards and subsidies for the US delegation and the hungry riders. He has experienced them from the US delegation to the hungry, from the first-tier cities to the fourth-tier counties.

In 1992, A Bo once worked as a part-time delivery man in Suzhou, and later returned to Luoyang County, Henan Province to be the stationmaster of the US group delivery station for two years. Because I heard that there are many orders in first-tier cities, the unit price is high, and the monthly income can exceed 10,000 yuan, I came to Beijing this fall to become a hungry hummingbird takeaway crowdsourcing.

A Bo explained that both the US delegation and the hungry have special delivery and crowdsourcing teams. The riders who just entered the business generally choose to do "special delivery", which can guarantee the basic income in the team, but the experienced riders choose to do "crowdsourcing". It takes a little longer to take orders freely, and the price of the list that runs far away is higher.

In Abo’s view, Meituan has a very high penetration rate in third-and fourth-tier cities and sinking markets. In 2016, Meituan has opened up county markets such as Luoning, and it was not until 2018 that it was hungry to accelerate its entry into these areas.

In Beijing, the two platforms give crowdsourcing riders "almost the same amount of tickets". If you are hungry, 9 yuan crowdsourcing each ticket, praised 1 yuan, and Meituan crowdsourcing each ticket, praised 1.5 yuan. Coupled with weather subsidies, praise, attendance and other rewards, there is no difference in the overall income of riders.

There is only one difference. When the US group crowdsources meals and delivery is delayed, the rider’s deduction needs to be exempted through online appeal; When you are hungry, hummingbird crowdsourcing directly cancels the time limit for picking up meals from merchants, reducing the deduction fee for overtime delivery.

Such a difference in process is important for ABO. A Bo has always been careful. He said, "You have to run at least 7,000 yuan a month to take care of your family." He and three riders huddled in a 20-square-meter bungalow, and went out at 7: 00 a.m. until the early morning to make money and save money. He said that when his parents are old, he also wants to "marry a daughter-in-law to repair the house", and his two roommates have to support their wives and children in their hometown.

Even if he delivers hungry takeout food, A Bo is proud to have been the "Minions" of the US group. Every time in the dead of night, A Bo always misses the days when he delivered takeout in his hometown, boasting and betting. At that time, he was the most famous takeaway brother of the US group. Until now, he has been wearing the work clothes of the US group when shooting videos.

At that time, whenever the take-away rush hour passed, A Bo would watch Aauto Quicker eat and shoot a video. The boss curiously bet with him that if his fans exceeded 10,000, he would give 500 yuan a reward. Unexpectedly, Abo shot more than 250 videos in one year and gained nearly 40,000 fans, which also brought him confidence and anticipation.

He said that he often feels inferior because of unclear speech. However, in Aauto Quicker, many users in the same city will follow him to order "the same paragraph" for take-out, and a little girl from school specially came to ask for his signature.

What makes A Bo most proud is a good thing he did when he was a rider of the US Mission. At that time, there were many "Bao Ma non-profit organizations" on hand. When they found him in the live broadcast room and asked Abo to help send the donated materials to the local poor households, he did not hesitate. He rode an electric car for more than ten kilometers in one breath and sent the materials and his own money to the poor families.

There are not a few take-away riders like Abo all over the country, and they grow up with the distribution system that pursues efficiency and speed. But from a personal point of view, they even hope that the competition of take-away platforms will last longer and they can get more subsidies themselves.

From sight to poetry and distance.

From the factory to the takeaway platform, from the third and fourth lines to the first and second lines, it is one of the manifestations of the continuous extension and scale of the industrial chain in the competition process of the takeaway platform. As ordinary people in the internet tide, Xiao Xiao and A Bo revealed their helplessness to the pressure of life and their longing for the future. Most riders are busy with "struggling in front of them", but some people dream of "poetry and distance".

When I met Zhou Lei, he was recording the annual finals of CCTV variety show "Avenue of Stars". His other two identity tags were "Little Takeaway Brother God" who had more than 300,000 fans in his hands and the first takeaway rider who won the monthly championship of "Avenue of Stars".

Zhou Lei, 31, has lived in the rural area of Qinhuangdao since childhood. She never thought that she would embark on the road of performing arts. Singing is just a way to entertain herself and relieve pressure.

Before joining the US Mission, Zhou Lei was unemployed at home and didn’t want to go out. He said that there were not many job opportunities in the county. He worked as an ore truck driver and sold potted plants on the roadside. In order to let his children enjoy a better education, he borrowed money to buy a house and moved to the city.

Last October, Zhou Lei took a video of singing in a fast hand wearing the take-away work clothes of Meituan. Unexpectedly, it suddenly became popular and attracted more and more fans’ attention. He said that every day, someone waited for him to sing and order songs in the live broadcast room. After two months, the income of fans’ rewards was actually 40,000 yuan, which suddenly eased the family’s economic pressure.

The real turning point comes from the attention of the "talent scout" on the fast hand. In November last year, Aauto Quicker, a private letter from Zhou Lei, received an invitation claiming to be "the crew of Jilin TV variety show Family Fun Show", and left the county life circle for the first time to start recording programs in big cities. Since then, it has moved to bigger stages such as "100 seconds of gold" and "Avenue of Stars".

Zhou Lei felt the power of the Internet. He said that TV editors and directors will not charge a penny for discovering "material" on a short video platform like Aauto Quicker. Moreover, there are many professional musicians in Kuaishou’s hands. They often interact and learn skills and give him professional guidance, which is a valuable resource for Zhou Lei who has never received professional music training.

Even when delivering takeout food, Zhou Lei obviously felt the love and respect of users. A customer named Zhou Lei to take delivery and asked him to sing a few songs on the spot. A local fast food restaurant also invited him to sing. Later, because of the popularity of Zhou Lei, it became the most famous "online celebrity Restaurant" in the county.

On Aauto Quicker, Zhou Lei was often teased by netizens as "a singer who was delayed by the take-away platform". However, he believes that it is the identity of the US group rider that makes him get more attention than others. Even on the performance stage of "Avenue of Stars", the yellow take-away uniform of the US Mission is his iconic image.

Zhou Lei, who became a monk halfway, hitchhiked on the Internet, and he became "the hope of the whole village" in the eyes of the villagers. More riders need to do their best to maintain the living needs of a wanderer and support their elderly parents and school children. More importantly, they all have light in their hearts, and they all have their own "poetry and distance", just like a small goal-to save money by their own efforts, to go back to their hometown to shoot a video of the mountain village one day, and to bring the villagers together to make a fortune.

"Meituan is a mysterious organization"

In fact, in the huge life industry chain composed of more than 500,000 riders, 4.4 million merchants and 380 million users, the rider profession is getting more and more recognition and respect. In the huge social and industrial transformation, riders are burdened with the confusion of life and the burden of family, and they are also looking forward to social recognition.

In the stories of several interviewees, take-away riders are a particularly mobile industry. Sometimes, a site with about 20 people changes more than a dozen people a month. Some people envy how much money they earn by sending takeout food. There are many experienced riders who have worked for several years. Some people leave because they can’t eat hard after working for a few days, and some people leave because of bad reviews from users and family reasons, just like a song sings, "When you say goodbye, you will leave."

For many riders, Aauto Quicker is a very special circle of friends. Usually, the original intention of sending videos is to cheer themselves up and tell strangers about their troubles that they can’t tell their family and friends, but they soon find out that they have found fellow villagers and peers here and found more understanding and recognition.

According to incomplete statistics, at present, there are more than 40,000 on-the-job riders in Aauto Quicker who use short videos to communicate, and there are not a few riders with tens of thousands and hundreds of thousands of fans. The "Little Fatty" with the most fans has attracted more than 950,000 people’s attention.

Xiao Pang said that in Aauto Quicker’s short videos, he could feel people’s goodwill and respect for the riders of the US Mission, and he also agreed that many videos reflected the hardships of riders’ lives.

For example, when a rider delivers food upstairs, the meal left downstairs is stolen, so he can only order another one at his own expense; When a rider comes across a slip with a wrong address or a hidden address, he can only call the customer again and again to explain it; Some riders have to pay for their own meals returned by customers because of overtime or spilled soup, so they have to take them home to eat; Some riders are sad in the center of the heavy rain, and they will stand on the road and cry while walking.

These common experiences give riders a natural sense of closeness. They cheer each other and share joys and sorrows. Xiao Pang said that he met many riders in Aauto Quicker, commented or interacted with each other live, and sometimes met and chatted in each other’s cities, just like they had known each other for many years. Now, Xiao Pang intends to transform into an e-commerce, and also find people to do business with through Aauto Quicker, and introduce and inspect the source of goods through the riders’ friends in Yiwu.

According to incomplete statistics, at present, there are more than 100,000 user-related and theme videos of Meituan riders published on Aauto Quicker platform, and many real stories of riders have been adapted into short video works. In these videos, riders use their own frustrations to dissuade boys who want to jump into the river and commit suicide. When they see kidnapped girls, they cleverly track and save people, take off their raincoats to take their babies out of the rain in the wind and rain, and try their best to rescue gas poisoning when taking meals in restaurants. They are "new urban youths" with ideals, skills and responsibilities, supporting the Internet life industry chain and conveying positive social energy, which has infected the fierce take-away business war with warmth.

In the eyes of more people in Aauto Quicker, "Meituan is a mysterious organization", because the rider brother in the video can do almost anything: they can catch thieves, help comatose old people, perform singing, play drums and even make a disc DJ in the street, draw a beautiful "Piggy Peggy" according to the requirements of the customer’s order, and even go to the kitchen to cook when the restaurant bursts …

Domestic C919 passenger plane officially rolled off the assembly line.

According to the introduction of the official website of COMAC CHINA, "C919" is the abbreviation of the code name of "COMAC919", and "COMAC" is the abbreviation of the English name of China Commercial Aircraft Co., Ltd. The "C" in the abbreviation is not only the first letter of COMAC, but also the first letter of the English name of China in China, which reflects that the large passenger plane is the will of the country and the expectation of the people.

C919 large passenger plane is a short-range commercial trunk aircraft with independent intellectual property rights in China. The standard range design range of C919 aircraft is 4075km, and the extended range design range is 5555km, which can meet the operating requirements of airlines for different routes. The maximum take-off weight of the standard voyage aircraft is 72,500 kg, and the maximum designed economic life is 90,000 flight hours/60,000 flight cycles /30 calendar years. The basic full economy class layout is 168 seats, and the mixed class layout is 158 seats.

C919 passenger plane in the final assembly process

A large number of advanced technologies are adopted in the design of C919, including: advanced aerodynamic layout and new generation supercritical airfoil and other advanced aerodynamic design technologies; Advanced engine to reduce fuel consumption, noise and emissions; Advanced structural design technology and a large proportion of advanced metal materials and composite materials; Advanced fly-by-wire control and active control technology; Adopt advanced integrated avionics technology; Advanced cabin comprehensive design technology to improve cabin comfort; Advanced maintenance theory, technology and methods to reduce maintenance costs.

C919 will use a large number of advanced composite materials and advanced Al-Li alloys, among which the amount of composite materials will reach 20%, and then the weight of the aircraft will be reduced through the detailed design of the internal structure of the aircraft. In addition, C919 will use domestic aluminum alloys, titanium alloys and steel, which account for 20-30% of the structural weight of the whole aircraft. C919 adopts four-sided windshield. This technology is an advanced technology in the world. At present, only the latest Boeing 787 is used in trunk passenger aircraft. Its windshield has a large area and a wide field of vision. Because of relatively few openings, it simplifies the fuselage processing industry and reduces the aerodynamic resistance of the aircraft head.

The C919 uses the LEAP-1C turbofan engine developed by CFM International, a joint venture between American General Electric and French SNECMA (Safran Group). The core engine of this engine is a 10-stage high-pressure compressor driven by a two-stage high-pressure turbine, and its total pressure ratio is as high as 50, far exceeding the current CFM-56 level of about 25. The blade profile in the high-pressure turbine adopts the third generation three-dimensional aerodynamic design, which has advanced aerodynamic characteristics and adopts high-performance materials and advanced cooling technology. According to relevant data, LEAP-1 can reduce fuel consumption by 16%, carbon dioxide emission by 16%, nitrogen oxide emission by less than 60% and be quieter than the existing CFM-56.

C919 passenger plane in the final assembly process

It is estimated that the localization rate of C919 is about 50% at the first flight, and it will exceed 90% after 2025. A great deal of equipment on this aircraft is made by China itself: the nose radar is made by AVIC Tianjin. The nose is made by AVIC Chengdu. The tail and vertical tail are made by AVIC Harbin. The center wing box, outer wing box, wing section and aileron are manufactured by AVIC Xi ‘an. The front fuselage, middle fuselage section and rear fuselage equivalent section are manufactured by AVIC Hongdu. The leading edge flap and trailing edge flap are manufactured by AVIC Changhe. AVIC Shanghai is the first production line and assembly plant, and AVIC Hongdu is the proposed second production line and assembly plant. In order to support the production and final assembly of C919, Nanchang Aviation Industry City (the new site of AVIC Hongdu) started construction in 2009, and it is planned to start producing the main components of C919 in the fourth quarter of 2012.

Chronology of C919 Development Events

In January, 2006, China listed the large aircraft project as one of the 16 major projects in the national medium-and long-term science and technology planning.

In August 2007, Hu Jintao presided over the Standing Committee of the Political Bureau and agreed to set up a preparatory group for the large passenger aircraft project.

In March 2008, the State Council approved the establishment of China Commercial Aircraft Corporation.

It was unveiled in May 2008. China Commercial Aircraft was inaugurated in Shanghai, with its headquarters in Shanghai. The registered capital of the company is 19 billion yuan.

In 2008, China Commercial Aircraft Co., Ltd. officially launched the demonstration of large passenger aircraft projects, mobilized the national strength and wisdom, invited 468 experts from 47 domestic and foreign units to form a large passenger aircraft joint engineering team, set up a large passenger aircraft expert consulting group composed of 20 academicians and experts, formed a preliminary overall technical plan for large passenger aircraft, completed the technical and economic feasibility study report of large passenger aircraft projects, and sorted out the first batch of 14 special technical research projects that need to be started.

In November 2008, the C919 project was officially launched, with the goal of providing a safe, comfortable, energy-saving, environmentally friendly and competitive short-range single-aisle commercial transport aircraft for the civil aviation market in 8-10 years.Initially, it is planned to complete the preliminary design in 2010, the detailed design in 2012, the first flight in 2014, and the airworthiness certificate and delivery to users in 2016.

In May 2009, AVIC Chengfei/Chengfei Civil Aircraft sent a joint design team to Shanghai Aircraft Design Institute to participate in the structural design of the prototype of C919 passenger aircraft nose project.

On June 19th, 2009, AVIC Chengfei/Chengfei Civil Aircraft completed the demonstration and release of the master plan for the manufacturing process of the prototype of the C919 project.

On August 31st, 2009, the full three-dimensional structure digital model of the C919 engineering prototype was fully distributed.

At 9: 30am on September 1st, 2009, the prototype of C919 nose started manufacturing in AVIC Chengdu Aircraft Co., Ltd.. The nose is 7.9 meters long, 3.96 meters wide and 4.16 meters high, including radar cabin, cockpit, toilet, kitchen and cockpit.

On September 8, 2009, the prototype of C919 was officially unveiled at the Asia International Aviation Exhibition held in Hong Kong. This is also the first time that the domestic C919 passenger plane has appeared in front of the world.

On November 24th, 2009, the assembly state of the upper and lower parts of the C919 die passed the evaluation, and the upper and lower parts were combined.

On December 8, 2009, the prototype of C919 project was officially rolled off the production line, and the whole project design and manufacture took only half a year.

On the morning of December 10th, 2009, the acceptance ceremony of the main structure of the prototype of C919 passenger plane nose project was held in AVIC Chengfei.

On December 21, 2009, AVIC Commercial Aircraft Engine Co., Ltd. and CFM International Co., Ltd. signed a memorandum of understanding in Beijing, and planned to establish a domestic joint venture production line for the final assembly and commissioning of LEAP-1C aircraft engines for C919.

On December 26th, 2009, the prototype project of C919 passenger plane nose was officially delivered to Shanghai Commercial Aircraft Corporation, which is another significant progress made in China’s large aircraft project.

In May 2011, China Commercial Aircraft Shanghai Pudong Assembly Base started construction, and it is planned that by 2020, it will have an annual production capacity of 150 C919 passenger planes and 50 new ARJ21 regional planes.

On November 16th, 2012, at Zhuhai Air Show, C919 passenger plane won a total of 100 orders from 6 Chinese and foreign customers.

On October 5th, 2013, Luo Ronghuai, Deputy General Manager of Comac China, said,The C919 plan may encounter a "setback". The C919 single-aisle aircraft produced by Commercial Aircraft Corporation of China was originally scheduled for test flight in 2014, but it has been postponed to 2015, and the delivery date of the aircraft will be postponed to 2017 or 2018. The large domestic aircraft in China may not be in service until 2020.

On December 31, 2013, the first nose part of C919 passenger plane project was assembled and removed from the frame. China Commercial Aircraft Corporation, AVIC and related units held a delivery ceremony at Chengfei Civil Aircraft Company, and unveiled the products of the first nose parts. The assembly of the machine head parts is mainly used for design verification test.

In May, 2014, Han Kecen, vice president of the Naval Aircraft Design Institute and executive director of the C919 project, confirmed that the C919 aircraft would make its first flight at the end of 2015.

On July 31, 2014, the head section of the first aircraft of C919 passenger plane was assembled off the assembly line of AVIC Chengfei civil aircraft.

On August 22, 2014, the first mid-plane fuselage of C919 passenger plane was assembled and rolled off the assembly line at AVIC Xifei 618 plant.

On August 29th, 2014, the midship/center wing and aileron section of C919 large passenger plane passed the airworthiness inspection at AVIC Xifei Company and reached the delivery status.

On September 19th, 2014, the first C919 passenger plane officially started the structural assembly work at China Commercial Aircraft Shanghai Pudong Assembly Base.

On October 8, 2014, the heads of the aviation industries of China and France said that the LeapX engine powered by the domestic C919 had been tested on the hook and successfully tested in the air.

On October 15th, 2014, the first aircraft nose of C919 arrived at Shanghai Pudong Base from Chengdu by land and water transportation.

On October 30, 2014, AVIC Shen Fei Civil Aircraft Co., Ltd. successfully delivered the first rear fuselage front section of C919 passenger plane here.

On February 11th, 2015, the rear fuselage of the first aircraft of C919 was manufactured by China Aerospace Haiying (Zhenjiang) Special Materials Co., Ltd. of the Third Academy of Aerospace Science and Technology, passed the airworthiness inspection and was officially delivered to Comac China.

On February 13th, 2015, the vertical tail of the first aircraft of C919 was delivered to China Commercial Aircraft by AVIC Shenfei Civil Aircraft Company.

In May 2015,According to sources, the first flight of C919 passenger plane will be delayed again until the first half of 2016, and the delivery time of the first batch of aircraft may be postponed from 2018 originally planned to 2020 at the latest.

On July 22nd, 2015, CFM International delivered the first LEAP-1C engine to China Commercial Aircraft.

On November 2nd, 2015, the first prototype of C919 passenger plane was officially rolled off the assembly line at China Commercial Aircraft Shanghai Pudong Assembly Base.