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The thermal power industry is the largest coal consumer, and the contribution of its air pollutants to PM2.5 has become a hot topic of public concern, which is worthy of in-depth study. There are a total of 32 thermal power generation enterprises in Jilin Province, of which 19 are coal-fired power generation enterprises, accounting for 59.37%. Based on the investigation and analysis of the basic situation of coal-fired power generation enterprises in Jilin Province, five typical coal-fired power generation enterprises have been identified as the research objects. In general, the larger the particle size is, the higher the removal efficiency will be. After analysis, it is concluded that the final smoke and dust discharged into the environment are mainly dominated by fine particulate matter. The filtration efficiency of a well-operated bag filter for PM2.5 is higher than that of an electric dust collector. The electric-bag compound dust collector combines the advantages of electric dust collector and bag filter and has the best filtering effect. The particles at the outlet of desulfurization drift to small-size particles.

This study presents a sustainability assessment of geothermal heating and cooling system of three buildings at the University of Illinois at Chicago - Grant, Lincoln, and Douglas Halls based upon the triple bottom line sustainability framework and presents a comparison between geothermal and conventional heating and cooling systems. Life cycle assessment (LCA) was performed to evaluate and quantify the environmental impacts for both geothermal and conventional systems. Similarly, economic impacts were evaluated by making a comparison between direct and indirect costs of both systems. Indirect costs were calculated using Stepwise 2006 incorporated in monetized LCA and compared that cost with social cost of carbon. Social impacts were quantified using Social Sustainability Evaluation Matrix (SSEM) which covers four major dimensions of society: social-individual, socio-institutional, socio-economic, and socio-environmental. An overall sustainability index for geothermal system and conventional system was calculated by evaluating environmental, economic, and social impacts using Integrated Value Model for Sustainability Assessment (MIVES) methodology. The results show that the geothermal heating and cooling system is more sustainable and environmentally friendly than the conventional system.

The technological breakthrough of energy storage and the rapid decrease in cost make the application prospect of energy storage in power system more and more extensive, and will play an increasingly important role in the safe and efficient operation of power system. The optimal arrangement of energy storage load operation is conducive to the maximization of economic profit on the grid side, which is of great significance to the satisfaction of power demand of the distribution network.

Without considering the existence of third-party audit supervision and considering the existence of third-party audit supervision, the principal-agent model of major engineering audits between government and audit organizations was constructed. The analytical solutions under various hypothetical conditions were analyzed for the government. The optimal incentive policy for major engineering audits provides the basis. The analysis results prove that, the introduction of third-party units for audit supervision can effectively stimulate audit behavior, reduce information asymmetry, and create higher engineering quality and audit quality in the process of major engineering audit.

Urban green infrastructure (UGI) attracts much interest because they could provide urban ecosystem services (UES). Among all various methodologies, the UGI structure-based modelling is favored for advantages in physiological mechanisms. This work concerns on environmental services, including “air purification,” “microclimate regulation,” “noise reduction,” “carbon sequestration and storage,” and “rainwater retention.” A new assessment methodology based on UGI structure indicator was constructed with nine UGI model structures and quantitative values. With implemented in two urban parks in Shanghai, this methodology is speculated to be suitable for patch-level cases, and can make certain efforts to regions without sufficient data.

In this paper, we investigate the problem of spectrum sharing in a secondary spectrum market where one secondary operator provisions network access services to a number of secondary users (SUs) by leasing spectrum from spectrum holder. For the system model under consideration, the spectrum allocated to the secondary operator can be shared by SUs. We model the interaction between the secondary operator and SUs as a two-stage Stackelberg game, where the secondary operator network price decisions in the first stage, and SUs make their spectrum demands decisions in the second stage. We use the backward induction method to solve this game. The numerical results show that the proposed solution method can capture the main factors of the secondary spectrum market, and provide a promising framework for the design of future secondary CR systems.

Since the reform and opening up in China, the rapid development of China's construction industry, especially after 2011, BIM technology in China has a rapid development and depth of application. This article mainly discusses the process of development of China's construction industry management and the process of development of BIM technology in China and, the use of software in China, the main use of revit in 3D modeling (design stage), the use of Guanglianda in the whole process of construction management. This article researches on Guanglianda and the applications were described, for example, in the integrated project of management information, labor management information, construction video surveillance, material management, material site acceptance. This paper also elaborates on the cooperation of Revit and Guanglianda in different stages. This paper also elaborates on a construction case in China, and makes a description of the problems of crane, facts and time, and then explores the reasons behind the rapid construction of China. And the feasibility of China's construction management approach to the introduction of Russia.

In this paper, we investigate the problem of spectrum allocation in Cognitive Radio Networks (CRNs) where a primary user (PU) leases its idle spectrums to a number of secondary users (SUs) who may have different willing to pay for these spectrums. For the PU, its main objective is to gain profit from selling the idle spectrums, and from the perspective of the Sus, they aim to maximize their utility from using spectrums. We model the interaction between the PU and SUs as a two-stage Stackelberg game, where the PU sets the prices for its spectrum in the first stage, and SUs make their spectrum demands decisions in the second stage. We use the backward induction method to solve this game. The numerical results show that the proposed solution method can increase revenue of the PU compared with the uniform pricing scheme.

Nowadays, various urban ecosystem services (UES) provided by urban green infrastructure (UGI) have been the concern of scholars worldwide. And as China being recognized as a living laboratory in sustainable studies, concerns toward UES provided by UGI and factors of urban dweller demands is definitely required. However, for related reviews and special discussions are lacking until now, this study calculated the types of UES and demand concerns with a collection of 54 Chinese and 51 English articles in UES studies, 162 Chinese and 26 English articles in urban dweller research. In addition, with detailed discussions through spatial distributions, perspectives, and methodologies, comprehensive analyses were conducted and unique features were summarized to back up other nations or situations worldwide.

Under the Internet thinking, manufacturing management mode is changed, it is not depend on the scale, but in the user as the center, more dependent on the reaction rate of user requirements. As the big data, cloud computing, Internet of things technology such as the development of technology, manufacturing is from automatic to intelligent evolution, on the user's personalized customization is possible. Using Internet thinking positive development manufacturing enterprise electronic commerce application mode of transformation and upgrading of manufacturing industry plays an important role. Promoting the continued ascent of manufacturing industry informatization level, promote the transformation of the manufacturing production mode, provide greater profit space for the export of products. In industrial 4.0 mode, the user is the core of the enterprise, C2B model will be the mainstream of future manufacturing e-commerce application mode. This paper to present the sorted out the basic model of manufacturing enterprise electronic commerce application, point out the existing problems, and the computing technology, communication technology, the constant development of storage technology, such as background, puts forward the corresponding countermeasure, points out that the C2B model is the development direction of manufacturing enterprise electronic commerce application mode.

In view of the current social background of power system becoming more and more complicated, and the current research situation of related fields, this paper discusses the common methods of power system risk assessment, including the method of hierarchy analysis, Markov chain model, Monte Carlo method, fuzzy comprehensive evaluation and related research progress. The advantages and disadvantages of the four methods are enumerated respectively. It is considered that the power system should be evaluated synthetically in the practical application and the effective risk assessment method should be adopted rationally.

In order to obtain reasonable parameters in the design of driving system of multi-axis hydrostatic transmission vehicle, the working principle of single-side drive of hydrostatic transmission vehicle is introduced. The matching and control of engine and hydraulic pump are analyzed. According to the driving equation of vehicle, The driving force required for driving system is determined, and the parameters of hydraulic motor, hydraulic pump, system working pressure and braking system are designed and calculated, which provides the parameter design for driving system of multi-axis hydrostatic transmission Reliable theoretical basis.

Organizational knowledge sharing is the key to improve the core competitiveness and production efficiency. How to govern the behaviour of knowledge sharing and promote knowledge sharing has become the focus of organizational knowledge governance. Under the exploration of the relationship between knowledge governance, knowledge sharing hostility and knowledge sharing within the Internet organization and empirical analysis, we draw the following conclusions: formal and informal knowledge governance have a negative and weak impact on the reasons of knowledge hoarding and rejecting and the attitude toward the failure knowledge; The reasons of knowledge hoarding and rejecting have a significant and negative impact on knowledge sharing, but passive attitudes towards failure knowledge have a positive influence on knowledge sharing; The reasons of knowledge rejecting and passive attitudes towards failure knowledge exist partial mediating effect between formal and informal knowledge governance and knowledge sharing, but the reasons of the knowledge hoarding does not exist.

According to steel billet marking theory of plasma arc nicking, the paper designs a dual laser ranging marking machine against online marking of special steel billet and realizes multi-character marking of the end face of hot steel billet. Writing mechanism bases on the rectangular coordinates marking form, Z axis adopts cantilever structure. It completes the overall marking task utilizing the synergy of KK module in X axis, Y axis and Z axis. It makes modal analysis on the writing mechanism model established by Pro/Enginner utilizing ANSYS Workbench at the position of X1Y1Z1, and obtains the first six order modal frequency and analyzes the vibration in the writing process. Moreover, the paper analyzes the static structure of the cantilever of writing mechanism, computes its maximum stress and total deformation. To make the writing mechanism reach the target of light weight, the paper optimizes Z-axis cantilever of writing mechanism. According to the analysis, it is known that the optimized Z-axis cantilever of the writing mechanism still meets the strength and rigidity requirement and total mass declines approximately 30%.

Aiming at the control problem of driving system of hydrostatic transmission chassis, the composition of the control system of hydrostatic transmission chassis is introduced and the control method of dual engine is solved. According to the number of driving axles in driving process, The external characteristic curve of the engine controls the variable hydraulic pump by one parameter, controls the rotational speed of the variable hydraulic motor according to the change of the vehicle speed, and introduces the control flow of the brake system. It provides a reference for the design of driving control system of multi-axis hydrostatic transmission chassis.

This paper deals with the analysis on the singularity of a 2UPS-UPR parallel machine tool newly designed by Northeastern University. On the basis of establishing kinematics equations, the Jacobian matrix of the parallel machine tool and the shape of the parallel machine tool workspace are obtained, the degree of operability which is the determinant value of the product of Jacobian matrix and its inverse matrix is taken as the performance index of the singularity. With MATLAB software, the change situation about the degree of operability within the workspace is simulated. The analysis results of this paper have laid the theoretical foundation for the position control and processing track planning of the parallel machine tool.

[Background] Mountain torrent disasters are one of the deadliest weather-related natural disasters in the world, often causing extremely serious economic and property losses and casualties; in recent years, due to heavy rainfall and complex geological and geomorphological conditions, mountain torrent disasters have occurred frequently in Gansu Province. An effective rainfall-runoff model is the key to prevent them. There are still many problems about how to establish suitable hydrological models in the arid basin of China. [Methods] Therefore, the Gulang River Basin in Gansu Province was selected as the research area to construct the HEC-HMS rainfall-runoff model; through the screening of different runoff methods, different runoff schemes were established to explore the optimal runoff algorithm for the arid basin; there are mainly SCS-CN method, initial and constant method, Green and Ampt method and exponential loss method in runoff generation; SCS unit hydrograph and Clark unit hydrograph methods are selected for slope transform, kinematic wave and lag algorithms for channel routing, totally 16 different runoff schemes. Three floods in the Gulang River Basin are selected to analyze the simulation effect of different runoff schemes in Gulang River Basin. [Results]1) If the Nash-Sutcliffe efficiency coefficient is selected as the evaluation index, the best simulation results are schemes 1 and 16 in the 20180826 flood, schemes 2 and 1 in the 20190626 flood and schemes 1 and 3 in the 20190911 flood. If the percentage of flood peak error is selected as the evaluation index, the best simulation results are schemes 16 and 1 in the 20180826 flood, schemes 9 and 6 in the 20190626 flood and schemes 13 and 4 in the 20190911 flood.If the percentage of runoff depth error is selected as indicator, the best simulation results are schemes 1 and 8 in the 20180826 flood, schemes 7 and 8 in the 20190626 flood and schemes 6 and 13 in the 20190911 flood. 2)The mean value of Nash-Sutcliffe efficiency coefficient obtained by the SCS-CN method for runoff generation, the SCS unit hydrograph for slope transform and the lag algorithm for channel routing are 0.8, 0.65 and 0.65, respectively; the mean absolute percentage errors of flood peak are 9.29%, 9.71% and 8.47%, respectively; the mean absolute percentage errors of runoff depth are 6.07%, 7.17% and 7.74%, respectively; the mean time difference of flood peak of SCS unit hydrograph for slope transform and lag algorithm for channel routing are 1.21 hour and 1.5 hour, respectively.[Conclusion]The most suitable scheme is the combination of the SCS-CN method for runoff generation, SCS unit hydrograph for slope transform, and lag algorithm for channel routing. The results can provide a certain reference for the prevention of flood disasters in the arid region of Gansu Province.

With the rapid development of the steel industry, the accumulation of steel slag increases year by year, occupying a large amount of farm land and leading the problem of environmental pollution and safety hazards. The current comprehensive utilization rate of steel slag is still very low in China, far behind the developed countries. The low comprehensive utilization rate of steel slag is a stumbling block to the green and sustainable development of the Yangtze River Economic Belt. Improving the comprehensive utilization rate of steel slag is an imperative way to resolve these problems and to realize sustainable development for the steel enterprise. Steel slag presents porous structure and large surface area; in addition, it is easy to separate from water due to its high density. Therefore, the application of steel slag in industrial waste water treatment has received intensive attention in recent years. This paper systematically introduced the research progress of steel slag resource utilization as absorbent materials for waste water and proposed the important improved method and critical problems for steel slag as absorbent materials.