Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network

As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency gaps.In this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is established.Combined with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation systems.The comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are predicted.Considering the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy process.The entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their subsystems.Finally,the weak links in energy utilization are identified,and energy conservation and consumption reduction are improved.The above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems.

Carbon efficiency evaluation method for urban energy system with multiple energy complementary

Urban energy systems(UESs)play a pivotal role in the consumption of clean energy and the promotion of energy cascade utilization.In the context of the construction and operation strategy of UESs with multiple complementary energy resources,a comprehensive assessment of the energy efficiency is of paramount importance.First,a multi-dimensional evaluation system with four primary indexes of energy utilization,environmental protection,system operation,and economic efficiency and 21 secondary indexes is constructed to comprehensively portray the UES.Considering that the evaluation system may contain a large number of indexes and that there is overlapping information among them,an energy efficiency evaluation method based on data processing,dimensionality reduction,integration of combined weights,and gray correlation analysis is proposed.This method can effectively reduce the number of calculations and improve the accuracy of energy efficiency assessments.Third,a demonstration project for a UES in China is presented.The energy efficiency of each scenario is assessed using six operational scenarios.The results show that Scenario 5,in which parks operate independently and investors build shared energy-storage equipment,has the best results and is best suited for green and low-carbon development.The results of the comparative assessment methods show that the proposed method provides a good energy efficiency assessment.This study provides a reference for the optimal planning,construction,and operation of UESs with multiple energy sources.

Evaluation of Chinese Learning Efficiency of International Students in China:Comparing by Dimension

This paper introduces the Value Engineering method to calculate the value coefficient of Chinese learning efficiency for 377 international students by dimension.Results suggest that attention should be paid to male,European and American,rural,introverted,and“work or education needs”international students;Give full play to the driving role of the reference-type,explore the space for improving the learning efficiency of the improvement-type and attention-type,and pay attention to the problems of problem-type international students.

Evaluation of Chinese Learning Efficiency of International Students in China

This paper investigates the related factors of Chinese learning engagement and performance of 377 students from three universities in Guangzhou of China,employs the value engineering method,and calculates the value coefficient of learning efficiency.From the value coefficient of Chinese language learning,it proves that over 60%of international students studying in China have a higher efficiency in learning Chinese.

Evaluation of Energy Efficiency and Analysis of Influencing Factors of Company CW’s Manufacturing Workshops

In this work,the Slacks-Based Measure(SBM)model within Data Envelopment Analysis was employed to establish a set of indicators for evaluating the energy efficiency of manufacturing workshops.The energy efficiency of 12 Company CW’s manufacturing workshops from 2016 to 2022 was assessed.The findings indicated that aside from a few workshops operating at the production frontier,the rest exhibit significant fluctuations in energy efficiency and generally low energy efficiency.Subsequently,a combined GRA-Tobit analysis model was introduced to identify factors influencing the energy efficiency of Company CW’s manufacturing workshops.Regression analysis revealed that technological investments,employee quality,workshop production scale,investment in clean energy,and the level of pollution control all significantly impact the energy efficiency of Company CW’s manufacturing workshops.By evaluating the energy efficiency of Company CW’s manufacturing workshops and studying their influencing factors,this research aids company managers in understanding the energy efficiency of the manufacturing process.It optimizes the combination of various production elements,thereby offering effective guidance for improving the energy efficiency issues of the company’s manufacturing workshops,which can contribute to enhancing the corporation’s overall energy efficiency.

Research on Evaluation and Optimization of Regional Land Use Structure Efficiency

[Objective] The purpose of this study is to judge the rationality of land use structure from new perspectives and method. [Method] The theory of data en- velopment analysis （DEA） has been employed in this article. A case study of evalu- ation of land use structure for Wujin district in 2012 is provided to illustrate the ap- plication of this research model. At the micro perspective, land use efficiency has been analyzed by use of data envelopment analysis model. The optimization and adjustment direction in land use structure has been pointed out from the view point of land use efficiency. [Result] The result has shown that the research method based on information entropy and data envelopment analysis model can effectively overcome the drawback of traditional evaluation techniques. Compared with the tra- ditional methods, the new optimization model based on a structure of the multi-crite- ria factors and objective weighting method can evaluate the rationality of land use structure more comprehensively.

Program evaluation and its application to equipment based on super-efficiency DEA and gray relation projection method

For the gray attributes of the equipment program and its difficulty to carry out the quantitative assessment of the equipment program information, the gray relation projection method is simply reviewed. Combining the super-data envelopment analysis（DEA） model and the gray system theory, a new super-DEA for measuring the weight is proposed, and a gray relation projection model is established to rank the equipment programs. Finally, this approach is used to evaluate the equipment program. The results are verified valid and can provide a new way for evaluating the equipment program.

The Synthetic Evaluation of Warhead Overall Efficiency

The evaluation system of smart ammunition warhead overall efficiency has been established in this paper. Allkinds of evaluation methods have been analyzed. Having led the concept of hierarchical structure into technique for orderpreference by similarity to ideal solution (TOPSIS) method, we put forward the step TOPSIS method which is suitable forevaluating the overall efficiency of smart ammunition warheads. In the calculation of index weight, the graded weight cal-culus is put forward which hardly relies on the subjectivity of decision-makers and can reflect the sensitivity and compatibili-ty of the index. In the graded weight calculation, the proportional-arithmetic weight value calculus and sensitivity-compati-bility weight value calculus are given respectively.

Evaluation of Surface Relative Humidity in China from the CRA-40 and Current Reanalyses

Recently,the China Meteorological Administration(CMA)released a new Global Atmospheric Reanalysis(CRA-40)dataset for the period 1979−2018.In this study,surface relative humidity(RH)from CRA-40 and other current reanalyses(e.g.,CFSR,ERA5,ERA-Interim,JRA-55,and MERRA-2)is comprehensively evaluated against homogenized observations over China.The results suggest that most reanalyses overestimate the observations by 15%−30%(absolute difference)over the Tibetan Plateau but underestimate the observations by 5%−10%over most of northern China.The CRA-40 performs relatively well in describing the long-term change and variance seen in the observed surface RH over China.Most of the reanalyses reproduce the observed surface RH climatology and interannual variations well,while few reanalyses can capture the observed long-term RH trends over China.Among these reanalyses,the CFSR does poorly in describing the interannual changes in the observed RH,especially in Southwest China.An empirical orthogonal function(EOF)analysis also suggests that the CRA-40 performs better than other reanalyses to capture the first two leading EOF modes revealed by the observations.The results of this study are expected to improve understanding of the strengths and weaknesses of the current reanalysis products and thus facilitate their application.

Evaluation of Land-Use Efficiency Based on Regional Scale——A Case Study in Zhanjiang,Guangdong Province

Evaluating land use efficiency is critical to the revision of general land use planning. An assessment indicator system for regional land use efficiency was established in this paper from the aspects of society,economy,ecology and environment. The weight of each indicator was defined by an analytical hierarchy process (AHP) and the entropy method (EM). Then,a case study in Zhanjiang was carried out to analyze the regional land use efficiency from 1996 to 2004 and its development by using the method of multifactor composite evaluation and an analytical model of the de-gree of coordination. The results indicate that land use efficiency with respect to society and the economy improved,whereas the ecological and environmental efficiencies were found to decrease. The degree of coordination in Zhanjiang is still at the status of basic coordination. Finally,measures for enhancing the ecological and environmental establish-ment are suggested in order to improve the regulations of land use structure and patterns,establish ecological forests for the public good and green corridors and prevent the soil erosion.

Application of a mixed DEA model to evaluate relative efficiency validity

Data envelopment analysis(DEA) model is widely used to evaluate the relative efficiency of producers. It is a kind of objective decision method with multiple indexes. However, the two basic models frequently used at present, the C2R model and the C2GS2 model have limitations when used alone,resulting in evaluations that are often unsatisfactory. In order to solve this problem, a mixed DEA model is built and is used to evaluate the validity of the business efficiency of listed companies. An explanation of how to use this mixed DEA model is offered and its feasibility is verified.

Comprehensive evaluation of rural courtyard utilization efficiency:A case study in Shandong Province,Eastern China

China is implementing the strategy of Rural Revitalization.Revitalizing idle and inefficient utilization courtyards is an important measure for rural revitalization.The evaluation of courtyard utilization efficiency is the basis of determining the idle and inefficient utilization courtyards in order to revitalizing it.This study provided a reference for the optimal use of rural courtyard utilization and revitalization through the quantitative comprehensive evaluation of courtyard utilization efficiency and the classification of courtyard utilization types.Taking Shandong Province in Eastern China as study area,we selected eight surveyed villages by stratified sampling method.According to the scale of the villages,full survey and sample survey were used,while middleaged men who familiar with the courtyards were selected as the respondents.Through a household questionnaire survey and face-to-face interviews from2017 to 2018,578 questionnaires of rural courtyardsin eight villages were obtained.Then based on the functions of rural courtyard and land resource conditions,16 comprehensive factors were formulated,involving land conditions,construction conditions and economic benefits,to build the comprehensive evaluation index system of rural courtyard utilization efficiency.Next the index weight was determined by analytic hierarchy process,and the linear weighted regression model was used to evaluate the utilization efficiency of rural courtyard.Finally,the K-means clustering analysis was used to classify the utilization efficiency of courtyards.The results showed that among the eight villages,the average utilization efficiency of courtyards was moderate(one village was low,five were moderate,and two were high).The proportions of both idle and inefficiently utilized courtyards were high.There were three vital factors leading to the idle and low efficiency of rural courtyards.They were declining rural industries,limited arable land per capita,and more farmer workers.In this case,the utilization efficiency of courtyards should be improved by transferring rural land,developing secondary and tertiary industries,evaluating the development potential of villages,classifying and optimizing courtyard utilization,so as to make full use of idle and inefficient courtyards,increase the income of farmers and collectives and promote the revitalization of rural areas.

Energy efficiency evaluation based on DEA integrated factor analysis in ethylene production

Energy efficiency evaluation plays an important role in energy efficiency improvement of the ethylene production. It is observed from the actual production data that the ethylene production energy efficiency often varies with the complex production working conditions. In the favored methods for energy efficiency evaluation,DEA models may show poor resolution when directly used to evaluate the efficiency values. Therefore, a new energy efficiency evaluation method for ethylene production is proposed based on DEA integrated factor analysis with respect to operation classification. Three key factors, including raw material composition, cracking depth and load rate, are taken into account in determining the production working conditions by means of k-means algorithm. Based on the multi-working conditions mode the energy efficiency evaluation of the ethylene production is made by using DEA model, where the most related energy data are screened by factor analysis.Furthermore, the supporting decision of energy efficiency improvement is provided to the operators. The accuracy and effectiveness of the proposed method are illustrated by applying in a practical ethylene production,which gives more effective energy efficiency evaluation in the complicated working conditions of ethylene production with declined dimension of input indicators.

Research on China's Aquaculture Efficiency Evaluation and Influencing Factors with Undesirable Outputs

Taking the aquaculture area, the number of farming boats and that of aquaculturist as input variables, the aquaculture production as desirable output variable and polluted economic loss as undesirable output variable, this paper conducts SBM model to evaluate the aquaculture efficiency based on the data of 16 aquaculture-developed provinces in China from 2004 to 2011. The results show the efficiency in China has not changed much in recent years with the efficiency values mainly between 0.39 and 0.53, and the efficiency of marine-aquaculture-dominated provinces is generally higher than that of freshwater-aquaculture-dominated ones. To analyze the difference under the efficiency, the panel Tobit model is used with education level factor, training factor, technology extension factor, technical level factor, scale factor and species factor as the efficiency influencing factors. The results show that technology extension factor and technical level factor have significant positive influence.

Promoting energy efficiency reconstruction for existing buildings based on comprehensive benefit evaluation

The purpose of the comprehensive benefit evaluation of the existing building energy saving renovation project is to promote the healthy development of the energy saving reconstruction. Therefore, it is necessary to reflect the value and function of incentive and restraint. The concrete embodiment is that: improving energy saving standard renovation of existing buildings, promoting the construction of energy efficiency labeling system, and strengthening the construction of government supervision system by the comprehensive benefit evaluation.

Integrated energy efficiency evaluation of a multi-source multi-load desalination micro-energy network

With increasing global shortage of fresh water resources,many countries are prioritizing desalination as a means of utilizing abundantly available seawater resources.Integrated energy efficiency evaluation is a scientific method for the quantitative analysis of energy efficiency based on multiple indicators and is very useful for investment,construction,and scientific decision-making for desalination projects.In this paper,the energy efficiency evaluation of the micro energy network (MEN) of desalination for multi-source and multi-load is studied,and the basic idea of comprehensive energy efficiency evaluation is analyzed.The process includes the use of a MEN model to establish an integrated energy efficiency evaluation index system,taking into consideration energy,equipment,economic,environmental,and social factors.A combined evaluation method considering subjective and objective comprehensive weights for multi-source multi-load desalination MENs is proposed to evaluate the energy efficiency of desalination and from multiple perspectives.

Identification and evaluation of high nitrogen nutrition efficiency in rapeseed(Brassica napus L.)germplasm

To establish identification and evaluation methods of N(nitrogen)absorption and utilization of rapeseed(Brassica napus L.),difference of N nutrition efficiency(NNE)among rapeseed germplasms and relationship between NNE and plant traits under various N application rates were analyzed in this research.Pot cultivating experiments were conducted to investigate NNE with 3 N application rates in soil(0.05,0.2 and 0.3 g/kg).A total of 12 rapeseed germplasms were planted,nitrogen absorption efficiency(NAE)and nitrogen utilization efficiency(NUE)in seedling stage,bolting stage,initial flowering stage,final flowering stage,and maturity stage were obtained.Results showed that bolting stage was the best period for NAE identification and evaluation.Low N application rate in soil(0.05 g/kg)was the best for NAE,and the indirect indexes were basal stem diameter,plant root dry weight and above ground plant dry weight.Maturity stage was the best period for NUE identification and evaluation.High N application rate in soil(0.3 g/kg)was the best for NUE,and indirect indexes were above ground plant dry weight and basal stem diameter.N application rates of 0.05 g/kg in soil was the best for nitrogen harvest index at maturity stage,and indirect indexes was number of pods per plant.Plant traits of rapeseed germplasms affected NNE.Higher basal stem diameter,plant root dry weight and above ground plant dry weight at bolting stage under low N application rate were important characteristics of N absorption in rapeseed.Higher above ground plant dry weight and basal stem diameter at maturity stage under high N application rate were important characteristics of N utilization.Higher number of pods per plant at maturity stage under lowe N application rate was an important characteristic of N harvest index.These results provided a reliable index for N management and provided theoretical basis for guiding rapeseed breeding.

Realistic Efficiency Evaluations for Parallel Computations under Workstation Cluster

In recent years, high performance scientific computing under workstation cluster connected by local area network is becoming a hot point. Owing to both the longer latency and the higher overhead for protocol processing compared with the powerful single workstation capacity, it is becoming severe important to keep balance not only for numerical load but also for communication load, and to overlap communications with computations while parallel computing. Hence,our efficiency evaluation rules must discover these capacities of a given parallel algorithm in order to optimize the existed algorithm to attain its highest parallel efficiency. The traditional efficiency evaluation rules can not succeed in this work any more. Fortunately, thanks to Culler's detail discuss in LogP model about interconnection networks for MPP systems, we present a system of efficiency evaluation rules for parallel computations under workstation cluster with PVM3.0 parallel software framework in this paper. These rules can satisfy above acquirements successfully. At last, two typical synchronous,and asynchronous applications are designed to verify the validity of these rules under 4 SGIs workstations cluster connected by Ethernet.

Numerical simulation of four-wave mixing efficiency and its induced relative intensity noise

Four-wave mixing, as well as its induced intensity noise, is harmful to wavelength division multiplexing systems. The efficiency and the relative intensity noise of four-wave mixing are numerically simulated for the two-wave and the three-wave fiber transmissions. It is found that the efficiency decreases with the increase of both the frequency spacing and the fiber length, which can be explained using the quasi-phase-matching condition. Furthermore, the relative intensity noise decreases with the increase of frequency spacing, while it increases with the increase of fiber length, which is due to the considerable power loss of the pump light. This investigation presents a good reference for the practical application of wavelength division multiplexing systems.

Promoting Balance in Output Efficiencies for Cross-Efficiency Evaluation in Data Envelopment Analysis

Cross-efficiency evaluation is recognized as an effective way of efficiency assessment for a set of decision making units (DMUs) in the framework of data envelopment analysis (DEA). It has been generally suggested that secondary goals be introduced for cross-efficiency evaluation owing to the non-uniqueness of optimal solutions in self-evaluation. This paper develops a variety of secondary goals in the spirit of promoting balance in the output efficiencies of the DMU under evaluation. The proposed models attempt to make each output contribute as equally as possible to the self-evaluated efficiency. In this way, the weight flexibility can for one thing be reduced by the introduced secondary goals with selections from alternate optimal solutions, in addition to counting on the dilution of flexibility in the subsequent peer-evaluation. The proposed approach might be applicable to evaluation problems in which multiple outputs are considered important and balance is encouraged to put all dimensions into sufficient use. The effectiveness of the proposed approach and its comparisons with some relevant secondary goals are illustrated empirically using numerical examples.