Design and Study of Could Platform Based Sampling Control and Management System

Hecheng WANG, Xiangqun ZHENG*, Chunxue ZHANG, Ming CHE, Yan XU, Bo YANG, Xiaocheng WEI, Qiang WANG

1. Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin 300191, China; 2. School of Computer Science and Technology, Tianjin University, Tianjin 300072, China

Abstract In view of the demand for intelligent and information-based management of sampling points for agricultural environmental monitoring, taking the cloud platform as the information carrier, combined with the advantages of GIS development interface technology on the Web side and intelligent handheld system development technology, the overall structure of the sample deployment control collection and sampling management system was designed, and a program flow method for the accurate perception of sampling points and the secondary evaluation of spare sampling points caused by geographic factors was proposed. It is expected to realize the intelligent and information-based sampling work from deployment to collection, and effectively increase the work efficiency. In addition, it is expected to provide a good data interface program for the input and output of related information at the Internet of Things (IoT) level for subsequent related data research.

Key words Cloud platform, Web GIS, Mobile GIS, Intelligent APP, System design

1 Introduction

With the constant development of mobile communication interconnection technology and intelligent terminal technology, the geographic information technology has been incorporated into the information technology, making it convenient to process and analyze spatial data in remote villages, and providing a powerful technical support for the intelligent and information-based monitoring and sampling work.

At present, a great deal of effort has been put into the joint operation of fertilizer formulation in China, and soil monitoring is the basis for testing the effect of the implementation scheme. Its work includes the collection of spatial positioning information and the management of attribute data related to samples. Researchers usually use satellite images as a reference basis to complete the placement of points on this basis. The sample collection personnel go to the site to compare the sampling plan with GPRS equipment to collect, number, package, and make paper record of the sampling location and related sample data information, and then bring the sample back to the unit, and then manually prepare spreadsheets to sort out the sampling data. In this process, the secondary data sorting records increase the data, increase the labor and time costs, and reduce the accuracy of the data. In addition, the update of latitude and longitude information is not synchronized, thus it is difficult to achieve consistent sampling points and layout scheme. In a serious case, a secondary collection may be required. Therefore, it is necessary to use a more advanced and systematic sample collection means, and provide a better information basis for monitoring sampling arrangement and control work relying on the Internet of Things (IOT) network, so the whole process is more scientific, accurate and standardized.

2 Related Technologies

2.1 IoT

The IoT is an information technology that has been widely used in recent years. It has been applied in various industries, integrating all kinds of network communication means, and combining such modern information technology as cloud service, artificial intelligence, and embedded development. It integrates various information collection and sensing devices into a powerful perception network, and collects all kinds of data through the network transmission and aggregation to the data platform. Through the application of relevant technologies, it is able to meet the requirements of safe and reliable remote data acquisition, rich network access and mobile applications for the whole process of monitoring sample collection, thus providing excellent data acquisition solutions in multiple ways.

2.2 Web GIS

ArcGIS Engine, developed by ESRI Company, is a special desktop application program at the beginning, and it is equipped with rich secondary development interfaces. With the development of server system and embedded system, its development interfaces have been extended to the development of Web page and mobile end, providing users with a wider range of GIS services. Especially for mobile GIS applications, it can provide object-oriented functional development solutions for different hardware development platforms. It has the characteristics of multi-platform compatibility, flexible use, and high development efficiency. It can provide a powerful technical support for more accurate identification and analysis of the collection point information during the sampling process, and can implement the original sampling plan to the maximum extent.

3 System architecture design

The sample collection, deployment, control and sampling management system takes advantages of the rich network connection methods of the IoT and the cloud data processing. It is divided into three parts: Handheld intelligent data processing layer, network layer, and application management layer. The system architecture is shown in Fig.1.

Fig.1 System architecture

(i) Handheld intelligent data processing layer: sampling tasks are obtained through the identification of user identity authority, then the sampling personnel are provided with the cruise function of each point, to ensure that the longitude and latitude coordinates of the actual sampling points are highly consistent with the layout scheme. After sampling at each point, the QR code of the sample can be generated and printed, and the relevant data transmission can be completed.

(ii) Network layer: this layer realizes the data interaction between the handheld intelligent data processing layer and the application management layer through GSM/CDMA mobile 2G/3G/4G network, WiFi network and network link carrier.

(iii) Application management layer: sampling layout plan information includes location coordinates of sampling points, coordinates of each point, sample types of each point (soil sample and water sample), sampling requirements of each point, detection indexes, allowable deviation degree of sampling coordinates and other relevant information. After the completion of each layout scheme, it is able to ensure the feasibility of the layout scheme by systematic evaluation or inviting expert database experts. Once the layout is determined, the system administrator can assign a single or multiple tasks to a single or multiple sampling workers. After the completion of the sample collection, the sample submission from can be generated and combined with the QR code to provide the input interface for sample testing information, which facilitates the collection and unified management of sample testing indicators results. Web page can not only complete the above operations, but also publish the monitoring sampling results to the managers and the public, and make the data interface open to the outside to realize the query and sharing of the sampling monitoring information.

4 Intelligent equipment hardware system

The hardware of hand-held intelligent system hardware is divided into six modules: CPU central main control module, storage module, power supply module, network communication module, I/O module, display module. CUP is mainly responsible for the data processing of the intelligent hardware system and assisting in implementing each instruction between the software and hardware of the system. The storage module is responsible for storing the running files of the handheld intelligent system software and the relevant data files needed in the process of program running. The power supply module provides a stable power supply for each hardware module. The network communication module implements GPRS navigation communication and a variety of wireless network communication links, to ensure the handheld intelligent data processing layer and application management layer between the data exchange and sampling point navigation function. On the one hand, the I/O module completes the printing function of the QR code of the sample adhesive. On the other hand, it integrates the point-position touch screen with the display module to achieve convenient and friendly man-machine interaction operation experience. The display module displays the regular program interface. The schematic diagram for this system is shown in Fig.2.

Fig.2 Hardware architecture diagram

5 Sampling point layout management system

5.1 Functional design

Sampling location layout management system is responsible for location layout and control scheme setting, scheme system evaluation and expert evaluation, sampling task allocation and sample information management, and it provides necessary information services for handheld intelligent device software system. The system can be developed using C# and MVC framework in ASP.NET. The database is built by Windows SQL Server. The front end uses HTML5, DIV + CSS, JavaScript and other client technologies. WebGIS function is realized based on Google map API interface. It is mainly divided into five subsystems: user management subsystem, point location control subsystem, scheme evaluation subsystem, sample information management subsystem and algorithm database subsystem. The functional design of each subsystem is as follows:

(i) User management subsystem: system administrators can deploy user rights in this system. The rights are mainly divided into three levels: system administrators, system operators, and experts.

(ii) Point location control subsystem: based on the Web GISAPI interface provided by Google Maps, users can monitor sampling points in a designated area through the satellite map interface, and generate the longitude, latitude, and high-level information of each point. Also, users can set auxiliary attributes of sampling such as: sample type (soil sample and water sample) at each point, sampling requirements at each point, sampling standard tolerance at each point and other relevant information, and finalize a complete point layout plan design.

(iii) Scheme evaluation subsystem: after the completion of the point location layout scheme, the corresponding evaluation can be submitted according to the requirements, which can be submitted to the system algorithm for evaluation, or experts in the expert database can be invited online to evaluate the scheme to ensure the feasibility of the scheme.

(iv) Sample information management subsystem: this subsystem is responsible for collecting relevant information of samples after sampling, generating inspection report according to the layout scheme, collecting inspection indicators after completion of testing, finally realizing the full information query, statistics and icon display of samples, and providing data sharing interface to the outside.

(v) Algorithm library subsystem: at the same time of satisfying its own system, this subsystem is responsible for the input and collection of algorithm models, and providing relevant interface services for the software system segment of handheld intelligent devices.

5.2 Visualization of point layout system

The intelligent acquisition management system is mainly used for the data interaction with the application management through the network layer, to realize the functions of the whole route guidance, the accuracy evaluation of sampling points and the upload of sampling information for the sampling personnel in their work. It is mainly divided into five subsystems: user identification subsystem, task execution record subsystem, sampling point cruise subsystem, sample information generation subsystem, and spare sampling point prediction subsystem. The functions of each subsystem are designed as follows:

(i) User identification subsystem: this subsystem obtains relevant information and system operation authority through user login of sampling personnel, and providing a basis for task management subsystem to obtain and distribute sampling work.

(ii) Task execution record subsystem: based on the user identification, it requests to download all or nearby sampling task information, makes a record of the entire implementation state of the task in the whole process of sampling, and sends data back to the application management in real time.

(iii) The sampling point cruise subsystem: it is responsible for obtaining the precise longitude and latitude information of each sampling point, guiding the sampling staff on the location of each sampling point through navigation function, judging the deviation of the location, and controlling the accuracy of the point.

(iv) Sample information generation subsystem: based on the sample information of the current collection point location, the corresponding sample number is generated after the completion of sampling. The sample number follows the sampling sequence of multiple point locations in a sampling task, and a letter is added at the beginning to distinguish it. Each sample can be printed as a unique sample QR code adhesive, which is convenient to scan the basic information of the sample and input the later test results.

(v) The spare sampling point prediction subsystem: when a point of the layout scheme in the sampling task is inaccessible due to geographical environment factors, alternative sampling points can be recommended as supplementary sampling points to ensure the number of sampling points is not missing while maintaining the efficiency and quality of the sampling work.

5.3 Accurate sampling point location perception and alternative sampling point discrimination program flow design

In the actual sampling process, ensuring the consistency between the sampling points and the layout scheme is the basis for ensuring the sampling quality, as well as the guarantee of the quality of the follow-up test data analysis results. During the sample collection process, the system will cruise each sampling point and guide the sampling personnel to each sampling point. When collecting samples, the handheld device uses its own location as the current actual sampling location. The system will compare the sampling standard tolerance properties in the point layout plan, and the sampling can be completed if it meets the requirements, print QR code label samples, complete the data upload, otherwise the system is not allowed to do sampling information upload and prompt to assess the alternative points. Users can choose the system evaluation, or complete the judgment of the prepared sampling points and the relevant data registration according to the actual situation. The program flow chart is shown in Fig.3.

Fig.3 Procedure flow of accurate sampling point location perception and alternative sampling point discrimination

6 Case study of system application

Participants in the whole business process from monitoring point location control to sampling task allocation to sampling task execution include system administrators, research administrators, sample collectors, evaluation experts and data operators. The main behavioral use cases include user management case, sampling point layout scheme case, scheme evaluation case, expert evaluation case, collection task assignment case, sample collection case, sample information summary case, GPS cruise case, GPS point positioning case,

etc.

Among them, the use case of sampling point layout scheme is to access the satellite map information through the data interface at the Web end and complete the sampling point layout operation in the planned sampling area on the basis of it. The scheme evaluation use case is responsible for completing the system evaluation of the layout scheme and providing the corresponding data service for the intelligent handheld intelligent device system by accessing the interface of the algorithm library. Expert evaluation use case is used for expert manual evaluation of the layout scheme. The sampling task is assigned to the use case for the Web end to complete the sampling layout scheme and pass the evaluation, and then assign the sampling task. The sample collection use case is used for the relevant information operation in the sample collection process. The use case of sample information summary is to link the data interface through the wireless network to complete the upload of sample information after sample collection. GPS cruise use case is used to guide sampling staff to each sampling point. The relationship between use cases is illustrated in Fig.4.

Fig.4 System use case analysis

7 Conclusions

The design of sample collection, deployment, control and sampling management system is based on IoT communication and service technology, using B/S Web development framework and Android intelligent system development framework, and combined with GIS development interface development. It completes the design of monitoring point layout, layout program evaluation, point layout task assignment management and execution, and sample information management, and realizes the overall information-based solution from sampling point layout, sample indicator monitoring, and data sharing and release. The system design idea improves the efficiency and accuracy of the original monitoring sample collection, and provides feasible solutions for the information management of the sample collection work of the relevant monitoring departments and the macro-system plan decision-making.