Performance Evaluation Mechanism Research Articles

Breaking the bottleneck of organic light conversion agents: Preparation, performance evaluation and intrinsic mechanism

Poor photostability has become a major obstacle of organic fluorescent dyes (OFD) used as light conversion agent. To explore the intrinsic mechanisms of photodegradation and highly efficient means to enhance photostability, here, three s-triazine dyes and two 1,3,5-triphenylbenzene luminescent agents were designed and synthesized. Further, the relationships of photostability, intramolecular charge transfer effect, energy gap between singlet and triplet, and active oxygen generating capacity are analyzed and discussed. AIE activity, solid-state fluorescence emission, light conversion quality, and photostability combined with thermostability show TPT-DB (2,4,6-tris(4-(3,6-ditertbutyl-9H-carbazol-9-yl)phenyl)-1,3,5-triazine) is the best light conversion agent among of the dyes, whose photosynthetic photon flux density at 400–500 nm and 600–700 nm in doping film increased successively to 6.20% and 25.78% of the blank film, emission intensity can maintain 93.4% of the initial value after intensified UV radiation of 20 h (365 nm, 40 w), and has good thermal stability, Td up to 374 °C. Furthermore, oxygen-free environment was confirmed to be the most effective measure to enhance the photostability of OFD, thereby a simple and efficient method is adopted to block the diffusion of oxygen and significantly enhance the photostability of OFD by amphiphilic ethylene–vinyl alcohol copolymer. The work not only provides an excellent light conversion agent, but also clears the obstacles for the large-scale application of OFD as light conversion agents.

Performance evaluation and heat transfer mechanism for battery thermal management of autonomous underwater vehicles based on phase change material cooling

Battery thermal management is of great significance to enhance the comprehensive performance of autonomous underwater vehicles(AUVs). However, few relevant studies have been conducted on the AUV’s battery thermal management (BTM). In this work, the phase change material (PCM) cooling was proposed for AUV’s BTM with taking into account natural convection. The temperature behavior of the battery and the melting behavior of PCM were studied under different parameters including thickness of PCM and eccentricity between PCM and battery. In addition, the enhanced heat transfer mechanism of the PCM melting process was further revealed based on the temperature deviation index. More importantly, the dimensionless temperature control rate (TCR) factor and the dimensionless heat storage rate (HSR) factor were introduced to quantitatively evaluate and optimize the eccentricity on the enhancement performance. The results show that PCMs have an excellent performance in the battery thermal management of AUVs. Unlike the traditional view, the whole PCM melting process was further subdivided into three stages according to the thermal energy storage mode or heat transfer types. Increasing the eccentricity can accelerate the melting of the PCM, while the reduced time of complete PCM melting was not linearly correlated with the eccentricity. The optimal eccentricity between PCM and battery was 10 mm, i.e., the eccentricity ratio ε = 0.625. The temperature control performance rate and heat storage performance rate were enhanced by 29.4 % and 5.7 % at e = 10 mm, respectively. These findings can provide guidelines for accurate design of the PCM cooling system for the AUV’s battery thermal management.

Fiscal Decentralization, Government Environmental Preference and Industrial Green Transformation

Based on the theory of fiscal decentralization and sustainable development, and the mechanism analysis about fiscal decentralization and government environmental preference to promote industrial green transformation, using China’s provincial panel data from 2006 to 2019, this paper empirically tests the effect of fiscal decentralization and government environmental preference on industrial green transformation by stepwise regression, threshold effect analysis, and the panel simultaneous equation. Results show that fiscal decentralization promotes industrial green transformation, but it also has a certain inhibitory effect on the government’s environmental preference, which results in an insufficient government role in the process of industrial green transformation. In the long run, the influence of fiscal decentralization and government environmental preference has a threshold effect; also, regional heterogeneity exists, as with regional economic level improvement, the influence became stronger. According to the regional survey, fiscal decentralization has a positive effect on industrial green transformation in the eastern region, while it has no significant effect in the central region and a negative effect in the western region. Therefore, countermeasures are put forward, from aspects such as fiscal decentralization and environmental power structure reform, to optimizing the performance evaluation mechanism for improving the government’s environmental preference, so as to have a positive effect on the green transformation of industries.

Energy subsidies and carbon emission efficiency in Chinese regions: the role of the FDI competition in local governments

ABSTRACT Based on the Data Envelopment Analysis, this paper examines the economic effects of energy subsidies on carbon emission efficiency in the Chinese regions from 2003 to 2018. The special roles are given to fiscal decentralization and foreign direct investment competition of local governments. It is observed that an increase in energy subsidies per capita negatively affects carbon emission efficiency. The green-growth-oriented local energy subsidies, targeted at clean energy and low-carbon industries, positively affect carbon emission efficiency. Therefore, local economies can balance economic growth and carbon emission reduction requirements. Given these results, policymakers should change the original performance evaluation mechanism with economic growth as the goal and promote local governments to implement green growth and low-carbon economic development policies.

Fiscal Decentralization, Green Technology Innovation, and Regional Air Pollution in China: An Investigation from the Perspective of Intergovernmental Competition.

Fiscal decentralization (FD), as an institutional arrangement for the fiscal division between central and local governments, gives local governments the enthusiasm and autonomy to provide public products and services. With the dominance of environmental governance, how local governments can avoid intergovernmental “race to the bottom” issues through green technology innovation (GTI) is a matter of regional green development and continuous improvement of atmospheric environmental quality. Based on a sample of 30 provinces in China from 2003 to 2018, this paper uses the spatial Durbin model (SDM) to examine the relationship between FD, GTI, and regional air pollution and explores their spatial spillover effect and regional heterogeneity from the perspective of intergovernmental competition. The results indicate that the FD and GTI in various provinces had significant and regionally differentiated inhibitory effects on local air pollution. In Western China, due to the regional competition among local governments in terms of economic development, economic development-oriented fiscal expenditures crowd out environmental governance-oriented fiscal expenditures, which has led to the consequence that FD can intensify local air pollution and has a positive spillover effect, but the demonstration effect of green technological innovation can well moderate the effect of FD on air pollution. FD in the eastern region has played a positive role in promoting regional air quality improvement. However, its green technological innovation has not played a positive role in reducing emissions, and it plays a significant negative regulatory role in the emission reduction effect led by FD. Finally, the article puts forward policy recommendations in terms of a fiscal decentralization system, green technological innovation, and performance evaluation mechanism.

Higher Education Management and Student Achievement Assessment Method Based on Clustering Algorithm.

Monitoring and guiding instructional management require student performance evaluation. Traditional evaluation and analysis methods based on absolute scores, on the other hand, have certain flaws and are unable to fully reflect the information contained in student performance, thus limiting the impact of student performance evaluation on teaching and learning management. Data mining is regarded as the backbone technology for future information processing, and it introduces a new concept to the way humans use data. Schools must analyse and evaluate the performance of students in the same grade level and secondary school in a timely and staged manner. Clustering is a type of data mining that uses similarity rules to classify sample data into groups with a high degree of similarity. To address the difficulties caused by the wide variation in course difficulty in student performance evaluation, a method based on the K-means clustering algorithm is proposed. The K-means algorithm and the improved K-means algorithm with student information are investigated. The test results showed that the K-means clustering algorithm, the improved algorithm in this paper, and the fast global mean clustering algorithm all cluster the same randomly generated data set with noisy points, but the clustering time of the algorithm in this paper is only 0.04, which has obvious advantages. As a result, the clustering algorithm-based higher education management and student performance evaluation mechanism provides some insights for future research on student learning patterns. It is hoped that instructional administrators will gain a better understanding of students' learning characteristics so that they can better guide their teaching.

Alleviating “inhibited steady-state” in anaerobic digestion of poultry manure by bentonite amendment: Performance evaluation and microbial mechanism

This study systematically evaluated the effects of bentonite as a possible additive to alleviate the “inhibited steady-state” induced by ammonia and acid accumulation during anaerobic digestion. Continuous stirred tank reactors fed with poultry manure were operated at 35 ± 1 °C either with bentonite or not. The results demonstrate that bentonite amendment increased average specific methane production by 35% as suffered from steady-state at an organic loading rate of 6.25 g VS/L·d. 16S rRNA gene amplicon sequencing revealed that the relative abundance of electron-donating Sedimentibacter and Syntrophomonas, and electrophilic Methanosarcina was increased by 110%, 91%, and 49%, respectively. The genera were identified as crucial for alleviating “inhibited steady-state”, through establishment of a more robust syntrophic pathway of methanogenic acetate degradation. The enhancement might result from the accelerated electron transfer by bentonite, which is qualified for serving as an exogenetic electron mediator due to containing abundant redox-active metal elements.

Theoretical Research in Laboratory and Field Trial of Micro-Nano-Oil Displacement System Conformance Control Technology

Abstract In recent years, a series of field tests of a new micro-nano-oil displacement system (MNS) conformance control technology have been carried out in different oilfields, which can increase oil production and reduce water cut obviously. However, compared with its field application, the research on its performance evaluation and oil displacement mechanism is still in the initial stage. And it is urgent to carry out relevant research work. Therefore, this paper made a profound study on its physicochemical properties, reservoir adaptability, transport and deep fluid diversion ability, and oil displacement mechanism. Results show that MNS with a series of particle sizes in different sizes (from nanometer to micrometer) can be obtained. And it has good expansion ability. Through reservoir adaptability evaluation, the matching relationship between the size distributions of MNS particles and pore throat is given, which has important guiding significance for MNS particle size selection for target reservoir before field trial. Furthermore, MNS has strong transport ability. When migrating in the porous media, it shows the motion feature of “trapping, deformation, migration, retrapping, redeformation, and remigration,” which can obtain better oil incremental effect than traditional polymer flooding. Under the condition of the same agent type, composition, and slug size, the oil recovery rate can be further enhanced by 6.96%. In addition, MNS conformance control technology has obtained good technical and economic effect in the 8 oilfields, with the lowest input-output ratio of 1.67 and the highest of 14.37. The reason why MNS have the above-mentioned good performances depends on its advanced mechanism: the unique particle phase separation phenomenon. When transporting in porous media, MNS particles gather in the larger pore to form bridge blocking, and its carrier fluid displaces oil in the small pore. Working in cooperation, MNS can realize deep fluid diversion and expand macroscopic and microscopic swept volume.

Orthogonal vortices characteristic, performance evaluation and classification mechanism of a horizontal classifier with three rotor cages

Horizontal classifiers with multiple rotor cages have competitive advantages of larger process capacity and smaller cut size. This study represents the gas-solid simulation, performance evaluation and classification mechanism of a horizontal classifier with three rotor cages. The gas turbulence was modeled using the Reynolds stress model (RSM), and the particle flow was predicted by the dispersed phase model (DPM). More than fifty operating conditions were analyzed for the performance evaluation. A schematic map showing the gas-solid flow dynamics was constructed. It was found that three rotating gas screen are independently induced and evenly distributed around the rotor cages. The M-shaped axial and tangential velocities have strong shear and washing effect on the near-wall particle. The maximum particle residence time of the cut size can be hundreds of seconds. The experimental cut sizes range from 7.2 μm to 25.7 μm with high classifying sharpness index (>55%) and superfine particle yield (>71%).

Thinking and Analysis on Constructing Performance Evaluation Mechanism of University Budget

Thinking and Analysis on Constructing Performance Evaluation Mechanism of University Budget

Performance Evaluation of Public Management in View of Fuzzy DEA Model

The research on management performance evaluation and governance countermeasures of public utilities, as an important entry point, focus, and flash point of the combination of management science, engineering research, and public management research, not only highlights the implementation and implementation of the scientific outlook on development and correct outlook on political performance, so that the topic has distinct theoretical frontier, practical pertinence, and practical guidance. It also highlights the intersection and integration of multiple disciplines, combines normative research with empirical research, qualitative research with quantitative research, macro research with micro research, and method and technology research with concept innovation and institutional arrangement research, and strives to realize the integration and complementarity of research methods of management science and engineering and public management. The research of public management broadens new horizons, expands new fields, and provides new paradigms, methods, and means. Based on the weight of public utilities management performance evaluation indicators and the selection of empirical samples, this paper studies the basic principles and comparative advantages of fuzzy comprehensive evaluation model and DEA model, makes an empirical evaluation of public utilities management performance, draws evaluation conclusions, and analyzes the key factors affecting and restricting the level of public utilities management performance. From the research level of evaluation technology and methods to the level of institutional arrangement, it is the only way to realize the scientific, standardized, and institutionalized performance evaluation of local government public utilities management. The basic procedures of performance evaluation and the performance evaluation mechanism are introduced, and the establishment and improvement of the information fidelity system and result application system of public utilities performance evaluation are studied. Based on the evaluation conclusion and empirical analysis of public utilities management performance, aiming at the key factors affecting the level of public utilities management performance, this paper puts forward the governance countermeasures of public utilities from the aspects of establishing scientific public utilities management performance concept, innovating public utilities management system, establishing and perfecting public utilities investment management mechanism, and so on.

Flocculation performance evaluation and flocculation mechanism study of PAC/PMAPTAC composite flocculant in dyeing wastewater

Flocculation performance evaluation and flocculation mechanism study of PAC/PMAPTAC composite flocculant in dyeing wastewater

Retrospect and Prospect of the Financial Investment System of Vocational Education in the 70 Years since the Founding of New China

Ensuring the financial input of vocational education is an important foundation for the development of vocational education. In the past 70 years since the founding of New China, the financial investment system of vocational education in China has experienced four stages: establishment and rise, restoration and revitalization, development and adjustment, reform and improvement. Throughout the development process of financial investment system of vocational education in China, we can reflect on the imperfect financial investment system of vocational education, the unclear decentralization of central and local governments, the imperfect performance evaluation mechanism, the incomplete development of legal relief and so on. Therefore, it puts forward prospects for the development of vocational education, such as improving the vocal mechanism in the formulation of vocational education policies, clarifying the relationship between central and local governments in the financial input of vocational education, and sorting out the basic ideas of the design of vocational education allocation mechanism and so on.

全国重要生态功能区生物多样性保护成效区域对比评估

PDF HTML阅读 XML下载 导出引用 引用提醒 全国重要生态功能区生物多样性保护成效区域对比评估 DOI: 10.5846/stxb202105081205 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家重点研发计划项目(2016YFC0500204);国家自然科学基金(42001266) Regional comparative evaluation of biodiversity conservation effectiveness in National Important Ecological Function Areas Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:国家重要生态功能区是国家主体功能区战略实施和生态保护红线划定的基础,关系到全国乃至全球范围的生态安全。开展大尺度生物多样性保护成效区域对比评估对促进物种栖息地科学管理、提升国家生物多样性保护水平具有较为重要的意义。本研究以2015年《全国生态功能区划》修编版划定的24个生物多样性保护生态功能区为研究对象,选取生态功能区内或邻近生态功能区的国家级自然保护区核心区作为参照区,利用InVEST模型计算多年参照区生境质量指数,并从中筛选出最大值,构建全国尺度的生境质量指数参照基准,在此基础上,采用空间叠加分析方法建立保护成效指数,定量分析了24个重要生态功能区生物多样性保护成效空间对比差异。研究结果表明:(1)基于参照基准的生物多样性保护成效区域对比评估方法可以较好地应用于全国尺度,全国重要生态功能区生境质量指数参照基准呈现明显的"西北低,东南高"的分布格局,而重要生态功能区生物多样性保护成效则表现出"西北高,东南低"的空间差异;(2)位于华东和华南地区的重要生态功能区生态环境本底状况较好,东北和华中地区的重要生态功能区居中,而西北和西南地区的重要生态功能区生态环境本底状况较差;(3)2015年西北和西南地区的重要生态功能区生境质量指数基本与参照基准持平,表现为生物多样性保护成效较好,华中和华南地区的重要生态功能区生境质量指数小幅度低于参照基准,体现保护效果居中,保护效果较差的重要生态功能区则位于东北与华东地区,其生境质量指数大幅度低于参照基准。通过对全国尺度重要生态功能区生物多样性保护成效区域对比评估,为进一步完善国家生物多样性保护成效的绩效考评机制和转移支付提供科学依据。 Abstract:National Important Ecological Function Areas are the basis of implementing national main function area strategy and drawing ecological protection red line, which closely linked to the ecological security on a national and even global scale. It is of great significance to promote scientific management of species habitat and improve the national biodiversity level by spatial comparative assessment of biodiversity conservation effectiveness. In this study, the 24 ecological function areas for biodiversity conservation, which originated from the revised version of the National Ecological Function Zoning during 2015, were used for spatial comparative assessment. The core area of the national nature reserve inside or nearest the ecological function area was selected as the reference area, and the multi-year habitat quality index of reference area were calculated based on the InVEST model. Then, the maximum value of the multi-year habitat quality index as the habitat quality index reference at the national scale. Ultimately, the conservation effectiveness index was established by spatial overlay analysis method, and the spatial comparison differences of biodiversity conservation effectiveness were quantitatively analyzed in 24 important ecological function areas at national scale. The results showed that:(1) the regional comparative evaluation method of biodiversity conservation effectiveness based on reference can be better applied to the national scale. The distribution pattern of habitat quality index showed "low in the northwest and high in the southeast" for the reference area, while the biodiversity conservation effect presented "high in the northwest and low in the southeast" in the important ecological function zones. (2) the ecological environment background (reference) of ecological function areas in the East China and South China was better than the Northeast and Central China, and the ecological environment background of ecological function areas in the Northwest and Southwest was the worst; (3) the total habitat quality index of important ecological function zones was almost the same as the reference in the Northwest and Southwest, in other words, the biodiversity conservation was more effectively in these zones. The habitat quality index of important ecological function zones in the Central China and South China was slightly less than the reference, reflecting the conservation effectiveness was negative in these zones. The ecological function areas with the worst conservation effectiveness were located in the Northeast and East China, and their habitat quality index were significantly less than the reference. The results of the biodiversity conservation effectiveness in ecological function areas of national scale can provide a scientific basis for further improving the performance evaluation mechanism and transfer payment for the biodiversity conservation effectiveness. 参考文献 相似文献 引证文献

Research on the Supply Chain Performance Evaluation Mechanism Based on Emergencies

Some emergencies have produced enormous changes in market demand in recent years as the economy has progressed. The supply chain’s capacity to adapt to this market demand has a substantial impact on the company’s future growth. As the frequency of emergencies rises, emergency management is becoming increasingly critical for enterprises. This article examines the responsiveness and profit status of the supply chain under the three conditions of total complete information symmetry, incomplete information symmetry, and information asymmetry based on the information sharing degree of supply chain firms. The research offers a novel approach to emergency management. It makes recommendations for how the company may share information to improve its emergency management capabilities. Finally, the feasibility of the model is verified and analyzed by a case.

Performance based Risk driven Trust (PRTrust): On modeling of secured service sharing in peer-to-peer federated cloud

Peer-to-peer (P2P) federated cloud system has emerged as a promising service delivery model wherein multiple cloud service providers (CSPs) collaborate and share resources and services among themselves to fulfill the spikes in demand from their cloud service consumers (CSCs). It facilitates CSPs to accomplish the committed service level agreements (SLAs) to their CSCs. However, the lack of preexisting trust relationships and unawareness about the cloud infrastructure and service delivery performance among CSPs in a distributed environment poses a risk to the quality of service (QoS) being delivered. We address this challenge by proposing a trust model, PRTrust, for a peer-to-peer federated cloud system that capitalizes the triangular relationship of performance, risk, and trust for the participating CSPs. The main contributions of this work are: (1) providing a logical design and architecture for trust and performance management in a peer-to-peer federated cloud system; (2) providing a two-tier weighted performance evaluation mechanism for CSPs; (3) providing a risk evaluation mechanism for CSPs based on their current performance level; (4) providing an improvised mechanism to evaluate and manage personalized reputation-based trust for the participating CSPs; (5) providing a CSP selection mechanism from a trusted list of CSPs, using the evaluated performance-based risk, for sharing the resources and services in a peer-to-peer federated cloud system. The proposed PRTrust model has shown better threat resilient behavior in dealing with malicious peer CSPs when compared with the reference EigenTrust model.

MoHRiPA-An Architecture for Hybrid Resources Management of Private Cloud Environments.

The high demand for data processing in web applications has grown in recent years due to the increased computing infrastructure supply as a service in a cloud computing ecosystem. This ecosystem offers benefits such as broad network access, elasticity, and resource sharing, among others. However, properly exploiting these benefits requires optimized provisioning of computational resources in the target infrastructure. Several studies in the literature improve the quality of this management, which involves enhancing the scalability of the infrastructure, either through cost management policies or strategies aimed at resource scaling. However, few studies adequately explore performance evaluation mechanisms. In this context, we present the MoHRiPA—Management of Hybrid Resources in Private cloud Architecture. MoHRiPA has a modular design encompassing scheduling algorithms, virtualization tools, and monitoring tools. The proposed architecture solution allows assessing the overall system’s performance by using complete factorial planning to identify the general behavior of architecture under high demand of requests. It also evaluates workload behavior, the number of virtualized resources, and provides an elastic resource manager. A composite metric is also proposed and adopted as a criterion for resource scaling. This work presents a performance evaluation by using formal techniques, which analyses the scheduling algorithms of architecture and the experiment bottlenecks analysis, average response time, and latency. In summary, the proposed MoHRiPA mapping resources algorithm (HashRefresh) showed significant improvement results than the analyzed competitor, decreasing about percent in the uniform average compared to ListSheduling (LS).

Analysis of Leakage Current of HfO2/TaOx-Based 3-D Vertical Resistive Random Access Memory Array.

Three-dimensional vertical resistive random access memory (VRRAM) is proposed as a promising candidate for increasing resistive memory storage density, but the performance evaluation mechanism of 3-D VRRAM arrays is still not mature enough. The previous approach to evaluating the performance of 3-D VRRAM was based on the write and read margin. However, the leakage current (LC) of the 3-D VRRAM array is a concern as well. Excess leakage currents not only reduce the read/write tolerance and liability of the memory cell but also increase the power consumption of the entire array. In this article, a 3-D circuit HSPICE simulation is used to analyze the impact of the array size and operation voltage on the leakage current in the 3-D VRRAM architecture. The simulation results show that rapidly increasing leakage currents significantly affect the size of 3-D layers. A high read voltage is profitable for enhancing the read margin. However, the leakage current also increases. Alleviating this conflict requires a trade-off when setting the input voltage. A method to improve the array read/write efficiency is proposed by analyzing the influence of the multi-bit operations on the overall leakage current. Finally, this paper explores different methods to reduce the leakage current in the 3-D VRRAM array. The leakage current model proposed in this paper provides an efficient performance prediction solution for the initial design of 3-D VRRAM arrays.

Trade-Off Between Aquaculture Closures and Fishermen Livelihoods

The prohibition of aquaculture is an important policy instrument for water quality protection. However, there are lack of observations on the complex interactions between stakeholders in the limiting or closing of fisheries and the internal cooperative mechanism that balances the restoration of water bodies and the livelihoods of fishermen. Using evolutionary game theory and modeling, this article analyzes the complex mutual feedback strategy between local government and the affected fishermen in regard to water body restoration and livelihood security under fishing prohibition. The results show that (a) the performance evaluation mechanism of environmental protection, including rewards and punishments, can provide direct political traction and indirect material guarantees for local governments to perform their duties and allow water body restoration and the transition of fishermen to alternative livelihoods. (b) Whether the local government actively promotes aquaculture closures is restricted by the improvement in the aquatic environment, the aquaculture development under the existing livelihood, and the industrial economic benefits of the new livelihood. And the capacity of them contribute to the overall development of the local government. The development of the net income of both parties in the negotiation will shape the direction of a series of public policies that focus on aquaculture closures.

URBAN SPORTS SERVICE STRUCTURE FROM THE PUBLIC HEALTH CONTEXT

ABSTRACT With the improvement of the quality of life, the residents’ requirements for the construction of urban public sports services have gradually improved. In order to improve the current urban public sports service system, this study analyzes the existing public sports service through the construction of public sports service model. The results show that the current construction of public sports service has some defects, such as single construction subject, unbalanced regional development of sports service, lack of perfect performance evaluation mechanism of sports public service, and so on. Therefore, in the process of public sports service construction, we need to pay attention to the diversification of construction subjects, the cultivation of residents’ awareness of physical exercise, the improvement of performance evaluation mechanisms of sports public services, and the broadening of investment channels. These measures can improve the urban public sports service system from the perspective of public health, and create better quality public sports services. This study analyzes the problems existing in the construction of public sports service by building a model, and puts forward some suggestions for improvement, hoping to provide ideas for scholars who study related experiments.