The PM2.5 on the clouds

Absrtact: With the rapid take-off of China's economy, the development of environmental pollution problems intensified, haze in all regions raging, PM2.5 index frequent "explosion", the daily life of the people caused great trouble, aroused public opinion's strong concern. The Government attaches great importance to and put PM2.5 monitoring work in the focus of environmental protection work. Cloud creates storage independent innovation PM2.5 cloud monitoring platform breaks the traditional research and development way, utilizes the innovative design idea, causes the environmental protection and the cloud computing high-end technology organic combination, the structure massive monitoring data storage, the processing platform, may reflect each region's air quality microcosmic, provides the convenience for the public life and the city management.

Keywords: PM2.5 PM2.5 cloud monitoring Platform cloud creation storage environment protection

I. Construction BACKGROUND

At the beginning of this year, the national environmental analysis of the People's Republic of China reported that less than 1% of the country's 500 largest cities met the WHO air quality standards. A number of experts accept the "Economic reference newspaper" reporter interviewed, said that governance PM 2.5 exceeded the standard, should be as soon as possible in the industrial structure, energy structure, urban planning and other aspects of measures, the top design of the radical solution.

At present, the domestic Environmental Monitoring Center site is less, distributed, environmental monitoring data can reflect the overall air quality of the city from the macroscopic, but it can not reflect the quality of the air in the local area or the specific region, which needs to build more environmental monitoring stations, and provide more real-time data.

At present, there are particulate pollutants under 350 meters in China, the degree of pollution is more serious, and the public's concern for PM2.5 is increasing, which makes the monitoring of PM2.5 more and more important. Foreign set of PM2.5 environmental monitoring instruments in the price of 100,000 U.S. dollars, domestic prices in 100,000 yuan, the price is expensive. The construction of more environmental monitoring stations requires huge capital investment, and costs are too high. The PM2.5 cloud monitoring platform with high cost performance can solve the problem of capital investment, meet the measurement precision, and complement the existing automatic monitoring system of air environment, and serve the Environmental Protection Department.

The PM2.5 cloud monitoring platform, which can be deployed on a large scale, is based on IoT technology, combined with cloud computing storage and processing technology, combined with the independent research and development of low-cost PM2.5 Environmental monitoring hardware system, in view of the current domestic key areas of air pollution control, improve urban air quality management needs, combined with weather conditions Urban traffic, population density, industrial production value and other elements, to carry out systematic research, in order to protect the environment, improve the regional atmosphere quality improvement plays a technical supporting role, as a large monitoring equipment supplement, Focusing on the problems of regional air pollution in PM2.5, monitoring environmental pollution, correctly analyzing and evaluating environmental quality, and seeking ways to improve atmospheric environment, it has a very wide application value, which can bring scientific decision basis to decision-makers, and thus systematically supervise the environment of the region.

Ii. developments at home and abroad

1, foreign PM2.5 monitoring development status

The PM2.5 standard, which was proposed by the United States in 1997, is mainly designed to monitor more effectively the small particles that are harmful to the human body that have emerged from the old standards as a growing industrial development. The PM2.5 index has become an important index to measure air pollution.

By the end of 2010, except for some countries in the United States and the European Union, which PM2.5 into national standards and imposed mandatory restrictions, most countries in the world have not yet monitored PM2.5, most of which are PM10.

The National Aeronautics and Space Administration (NASA) released a global air quality map in September 2010 to showcase the density of PM2.5 around the world. The map global air quality map is produced by two researchers at the University of Delphi, Canada. They drew a map showing the average of 2.5 PM from 2001 to 2006, based on the results of two NASA satellite monitors. In this picture red (ie PM2.5 density is highest), appears in North Africa, East Asia and China. The density of PM2.5 in north, east and central China is even closer to 80 micrograms per cubic metre, or even more than the Sahara desert. In this 2001-2006 average global air pollution situation map, the world's highest PM2.5 region in North Africa and China's north, east and Central Asia.

Fig. 1 The distribution map of the PM2.5 concentration in the city of 2 million vehicles with maneuvering capacity

Air quality monitoring sites in international cities are usually more numerous, and in London, for example, there are 103 monitoring points for PM10 only (particulate matter less than or equal to 10 microns in diameter). In addition, international cities such as Paris and Hong Kong have monitored and publicized the air pollution situation on both sides of the road.

It is noteworthy that the 2011 report stated that international cities, such as London, Paris and New York, which have been PM2.5 monitored and released by the city, and that many cities in the developing world, such as Mexico City and New Delhi, have already launched PM2.5 surveillance and dissemination.

2, the development of China's PM2.5 monitoring platform

According to statistics, at present, there are 74 cities in China already have the monitoring conditions for PM2.5, there are more than 600 PM2.5 monitoring points in China, but compared with the PM2.5 monitoring system of the international cities, the environmental air quality monitoring sites in our city can also reflect the overall environmental quality condition, but the monitoring sites are less, Lack of representativeness and coverage, monitoring projects, monitoring networks, number of measuring points and location design cannot meet the needs of human health impact exposure assessment in key regions.

At present, Jiangsu Environmental Protection Cloud Platform is the most advanced, Jina environmental information Most of an environment-friendly cloud platform, "1831" Environmental protection cloud Platform is not only the view of Jiangsu eco-environmental protection of the "Eye Rain Table", but also the environmental wisdom of Jiangsu decision-making important basis and means. "1831" cloud Platform using the International advanced things Networking sensors and information analysis cloud technology, It can realize the safety and health of the ecological environment within 102,600 square kilometers of 4 trillion economic total in the whole province, and integrate the human society and the environment Business system, so as to achieve the wisdom of environmental management and decision-making in a more precise and dynamic way. In fact, the cloud platform gathers the data not only includes the key pollution source automatic monitoring, the watershed water quality automatic monitoring and so on real-time data, the Environmental Protection Department as the situation, 12369 reports the information, the environment creation situation and so on the data form set into the platform, each day platform Jina data more than 3 million.

Due to the limitation of economic and technical conditions and the development of environmental air monitoring in China, many areas of China's environmental air quality monitoring network is not mature enough, and the cost of PM2.5 monitoring sites to make the cloud platform can not start, the society needs more like "1831" such advanced systems in the country everywhere.

Three, large-scale deployment of PM2.5 cloud monitoring platform

The PM2.5 Cloud monitoring platform is a system composed of PM2.5 cloud monitoring nodes, cloud platforms and web interfaces and scervices. PM2.5 Cloud Monitoring node by the advanced PM2.5 collector to carry out data collection, wireless data transmission through the GPRS, the information into the cloud platform through the cloud to create storage of independent research and development of data cube machine for historical data collection processing, real-time data warehousing system, data storage, data query analysis and data management. PM2.5 Cloud monitoring platform uses Cstor and Cproc to build an application PM2.5 cloud monitoring platform. The platform provides Web services that can be used to showcase the PM2.5 values of the current deployment environment and to track pollution sources. Figure 2 Below is the overall architecture of the PM2.5 cloud monitoring platform.

Fig. 2 overall architecture of PM2.5 cloud monitoring platform

1, PM2.5 Cloud monitoring Platform Front-End program

(1) Front-End technical framework

PM2.5 front-end equipment is mainly composed of power module, acquisition module and communication module, front-end equipment to collect relevant information, wireless data transmission through GPRS, in the public network IP server for data reception and preliminary processing, and then data stored in the data cube for storage and calculation, and the final processing and publication of data through the Web server. Details of the structure are shown in Figure 3.

Figure 3 PM2.5 Cloud monitoring platform front-end device architecture

(2) Deployment mode

In the different regions of the city and the effective use of PM2.5 cloud monitoring platform, it is possible to master the real-time monitoring data of the PM2.5 in different regions, different time periods and different climatic characteristics (including temperature, wind direction, season).

PM2.5 Cloud monitoring platform environment data acquisition equipment using advanced sensors, Low-power single-chip technology and network communication technology combined to provide a convenient way to query data, directly through the browser can directly access the test data.

At present, the monitoring equipment of the environmental monitoring station is generally deployed between the height of the ground 20m-25m, and the cloud-created PM2.5 cloud monitoring platform Environment monitor equipment is deployed according to the actual situation. Small equipment, flexible deployment mode, can be deployed in telephone poles and other public facilities. See Figure 4 for details.

Figure 4 Front-End equipment deployed on poles

(3) Collecting communication mode

At present, domestic and foreign environmental protection departments are widely used to monitor PM2.5, β-ray absorption and micro-oscillation balance. In addition to the above three test methods, there is a method of measuring the concentration of particulate matter by the principle of light scattering. The principle of the method is: the higher the concentration of particulate matter in the air, the stronger the scattering of light. After the scattering of light is measured, the concentration of particulate matter can be calculated. The test method is fast, high automation and easy to operate.

The PM2.5 Cloud monitoring platform uses the infrared light scattering method to carry out test-related data. The related data are collected by the relevant probes. The concentration of particles is obtained by infrared light scattering through the collected channels. The channel of collecting air has fixed heating source, and the dynamic collection of space is carried out by adding heat source. The relevant particle concentrations are converted into relevant data and transmitted through wireless communication.

The communication of front-end equipment is mainly through GPRS to transmit data wirelessly. Detailed data transmission Network Diagram is shown in Figure 5.

Fig. 5 GPRS data transmission

Data in the front-end equipment based on TCP/IP protocol, through the GPRS data transmission, through the mobile network, the use of public network to accept data, and then the data warehousing, data processing, and finally through the Web server to show the data.

(4) Power supply mode

PM2.5 Cloud Monitoring platform has two types of power supply, one is lithium battery and mains complementary power supply, the other is solar power supply mode. See Figure 6 for details.

Fig. 6 physical drawing of front-end equipment for solar power supply mode

2, PM2.5 cloud monitoring platform back-end program

(1) Backend technology architecture

PM2.5 Cloud Monitoring platform is a system which is located between the PM2.5 data acquisition and PM2.5 monitoring application. From the basic structure and structure of the system, the shared platform consists of the following main parts: Historical data collection processing system, real-time data warehousing system, PM2.5 cloud monitoring platform data storage System, PM2.5 cloud monitoring Platform Data Query Analysis application system, data management system. See system architecture Figure 7.

Figure 7 System Overall architecture diagram

(2) Main functions of PM2.5 cloud monitoring platform

Real-time Data warehousing system

The real-time data warehousing system is mainly responsible for the data from all the PM2.5 monitoring points in the city to the PM2.5 cloud monitoring platform data storage Center.

L PM2.5 Cloud Monitoring platform data storage System

The original PM2.5 data will be stored in the PM2.5 Cloud monitoring platform Distributed file system for storing massive unstructured data. In order to meet the different requirements of data quantity, data characteristics and query processing, partial storage is stored in the relational database.

L PM2.5 Cloud Monitoring Platform Data Query Analysis application System

PM2.5 data query analysis applications include real-time monitoring of air quality PM2.5, viewing of historical records and analysis of data functions. PM2.5 historical query processing, due to the large amount of PM2.5 data, it is necessary to dispatch multiple server nodes for parallel processing.

Data management System

In practice, a user may be interested in a particular time segment or type of data, and the data management system can be used to query and export this part of the data for use.

(3) Backend platform features

L System Extensibility

PM2.5 Cloud monitoring platform to fully use the cloud to create independent research and development of data cube technology advantages, plus the monitoring point only need simple configuration can be connected to the PM2.5 cloud monitoring Platform data Storage Center, uniform standard standards, name embodies PM2.5 cloud monitoring platform monitoring point of position, PM2.5 Cloud Monitoring Platform monitoring point number and so on to facilitate rapid retrieval; Customers need to be more storage devices and data Analysis server only need to be based on the data cube specification for simple modification configuration. For example, a storage node can be added dynamically if the subsequent amount of storage data is increased based on the PM2.5 cloud monitoring platform. Slow query speed only requires dynamic addition of a small number of processing nodes. Maximize customer cost savings, docking with existing system data to support each version of the database docking access Oracle, SQL Server, MySQL can be.

L System Reliability

As the system becomes larger and more complex, its reliability becomes more and more difficult to guarantee. Application itself to the reliability of the system running more and more high, in some key applications, such as aviation, aerospace, etc., its reliability requirements are particularly important in the banking industry, the reliability of its software system is directly related to its reputation and survival and development competitiveness. Especially, software reliability is more difficult to guarantee than hardware reliability, which will seriously affect the reliability of the whole system. The PM2.5 Cloud monitoring platform system uses the data cube's reliability mechanism to guarantee and enhances the data reliability.

L Data Query and statistical analysis subsystem

Cproc Cloud Processing is a research and development of cloud companies to deal with massive data processing framework, characterized by high real-time. The master-Slave management node monitors all processing nodes (slave), accepts tasks, assigns subtasks, monitors tasks, and handles various exceptions. Process nodes (slave), accept subtasks, monitor subtasks, and report tasks to the master node. The data query subsystem architecture is shown in Figure 8:

Figure 8 Data Query Subsystem architecture

The JSON string information from the front page is parsed and the variables are analyzed, the information needed to be queried is obtained, and the information is encapsulated into a protocol that is compatible with the database end, and the database is queried by the interface provided by the databases. After the database-side query completes, the byte results are stored in the specified file. The interface server is signaled, reads the file, and encapsulates the result into a string that is sent to the foreground interface. Figure 9 and 10 below are the Web page view real-time PM2.5 monitoring platform data.

Figure 9 Data page query interface

PM2.5 Monitoring Data Map

3, PM2.5 cloud monitoring platform advantage characteristics

(1) The advantages of comprehensive storage, processing and monitoring of massive data

Large-scale deployment of cost-effective monitoring points to form a huge amount of data, using cloud computing technology, high reliability storage, second level processing, real-time monitoring, analysis of data, timely alarm, help decision-making.

(2) Cost-effective advantages

Using X86 architecture low-cost computer to build cloud computing platform, using software fault tolerance instead of hardware fault tolerance, greatly reduce costs. Under the condition of target performance and reliability, it can save about 10 times times the cost of the traditional small scale commercial database scheme. can meet the PM2.5 monitoring, data transmission function, without expensive foreign monitoring equipment, and existing environmental monitoring points to form a favorable complement to the PM2.5 data release has reference significance.

(3) Real-time monitoring advantages

Under the support of high efficiency and parallel distributed software, the platform can complete PM2.5 data warehousing, analysis and management in real time, such as data summarization, data reporting, data warehousing, data query, data calculation and data management. Fast measurement, high degree of automation. The test method determines the real-time performance of the test, the acquisition time realizes the second level response, and the collection time can be set arbitrarily, the collected data is stored in real time, and can be queried in real time with unprecedented efficiency.

(4) High reliability Advantage

Based on the deep research and accumulation of cloud computing reliability, the problem of single point fault in distributed computing platform is solved completely. If any one node fails, the system will automatically block and no data loss will occur. It includes Query task assignment node, compute Task Assignment node, HDFS metadata node, HDFS data Storage node, MapReduce Job Tracker node, MapReduce worker node, HBase Management node, HBase region node, etc.

Processing platform in the case of non-stop machine, increase the number of nodes, the processing capacity of the platform automatically increased, reduce the node, the processing capacity of the platform automatically reduced, so that with the cloud computing platform seamless docking, according to the calculation and storage tasks dynamically apply or release resources to maximize the utilization of resources.

PM2.5 Cloud monitoring platform front-end equipment can be increased according to the requirements of the equipment, expand the coverage area of the entire system, but do not need to continue the complex operation, can dynamically increase the PM2.5 test node, access to the system, and can automatically network, with a strong capacity of expansion.

(5) The accuracy advantage of collecting data

The data collected are accurately calibrated and highly sensitive, and the PM2.5 data and trends that are released by the Environmental Protection section are close to the real and effective data. Figure 11 Below is a test comparison graph.

PM2.5 Test Comparison graph

Based on the above, PM2.5 Cloud monitoring platform architecture cloud data processing platform, storage of the region's massive data, the accumulation of long-term monitoring data for the study of environmental capacity, the implementation of total quantity control, target management, forecasting environmental quality, environmental governance to provide data.

Four, PM2.5 cloud monitoring platform construction benefit

China is speeding up the pace of industrialization and urbanization, and the impact of natural environment on society and the public is more and more, the government and society have put forward higher requirements for the emergency management work. In order to enhance the ability of disaster prevention and relief and to improve the response level of meteorological disasters, it is urgent to establish an authoritative, objective, unimpeded and credible information dissemination channel, so that the society and the public can understand the status, progress, trends, reasons and other information of various disaster events in time, and take effective precautions It is most likely to mitigate and avoid the hazards to economic construction and people's lives of all kinds of disasters. PM2.5 Cloud monitoring technology has built a good communication and supervision platform between government and public in the field of environmental protection, which is beneficial to the development of circular economy and the construction of harmonious society.

1. Economic benefits

The economic benefit of PM2.5 cloud monitoring platform is mainly embodied in the indirect economic benefit of the platform construction, the direct economic benefit produced by the operation and the government departments ' switching into the core business development by using the funds saved by the platform.

At present, PM2.5 cloud monitoring platform has been used in Jiangsu Province Environmental Protection Bureau fixed Risk Source monitoring project, has been implemented in Kunshan, and is intended as a PM2.5 monitoring platform demonstration project, at present the platform has been validated by the Nanjing Environmental Protection Bureau, the error rate is less than 5%, has been planned in Nanjing for application. This September, PM2.5 cloud monitoring platform in the Qinhuangdao Shi environmental Protection Testing station, Haigang District EPA, Beidaihe District Xinhua Sanatorium, Shanhaiguan District Environmental Protection Bureau monitoring station, the North Glass industrial Park Five monitoring points to complete the deployment, operation within 2 years, will achieve annual operating income of more than 10 million yuan, the annual net profit of 3 million yuan, For the Environmental Protection Department to save the monitoring point of deployment investment of 10 million yuan.

3-4 years of implementation of the project, the Service environmental protection departments will reach more than 40, to achieve annual operating income of more than 30 million yuan, the annual net profit of 10 million yuan, for the Environmental Protection Department to save the monitoring point of deployment of 30 million yuan.

In the next 5-6 years, the completion of the Yangtze River delta area to the East China platform expansion, the formation of sphere PM2.5 cloud monitoring platform situation, the realization of annual operating income of more than 300 million yuan, the annual net profit of 60 million yuan, for the Environmental Protection Department to save monitoring point deployment investment nearly billion.

2. Social benefits

At present, there are many gaps in the industrialization of PM2.5 monitoring, such as lack of reliable and low-cost sensors, cloud computing technology for large-scale storage and processing.

In the above background, Nanjing Cloud Chong Storage Technology Co., Ltd. self-developed PM2.5 cloud monitoring platform can be large-scale deployment, including self-developed highly reliable low-cost sensors, the current domestic leading technology cloud storage and processing technology, especially in the front-end PM2.5 monitoring miniaturization technology, Back-end data cloud computing storage and processing technology in the field of independent research and development, precision manufacturing and ancillary processing capabilities, will break the foreign monopoly in the PM2.5 monitoring system, is conducive to speeding up the environmental monitoring system of general, localization and industrialization of the development speed, with the city's existing environmental monitoring points, accurate, timely Comprehensively reflect the present situation and development trend of environmental quality, for environmental management, pollution source control, environmental planning and other scientific basis, combined with weather conditions, urban transport, population density, industrial production value and other elements, to carry out systematic research, in order to protect the environment, improve the quality of urban air environment to play a technical supporting role, The breakthrough of key technology will promote the technological progress of the industry greatly, impel the breakthrough of the localization of major technology such as PM2.5 monitoring technology standard, promote and drive the structure adjustment and development of the related industry of our country, enhance the international competitiveness of the domestic PM2.5 cloud monitoring platform, have important strategic significance.