Combined Weighting Research Articles

A time-evolving digital twin tool for engineering dynamics applications

This paper describes a time-evolving digital twin and its application to a proof-of-concept engineering dynamics example. In this work, the digital twin is constructed by combining physics-based and data-based models of the physical twin, using a weighting technique. The resulting model combination enables the temporal evolution of the digital twin to be optimised based on the data recorded from the physical twin. This is achieved by creating digital twin output functions that are optimally-weighted combinations of physics- and/or data-based model components that can be updated over time to reflect the behaviour of the physical twin as accurately as possible. The engineering dynamics example is a system consisting of two cascading tanks driven by a pump. The data received by the digital twin is segmented so that the process can be carried out over relatively short time-scales. The weightings are computed based on error and robustness criteria. It is also shown how the error and robustness weights can be used to make a combined weighting. The results show how the time-varying water level in the tanks can be captured with the digital twin output functions, and a comparison is made with three different weighting choice criteria.

Comprehensive evaluation of 5G+ smart distribution network based on combined weighting method-cloud model

With the large-scale application of 5G technology in smart distribution networks, the operation effects of distribution networks are not clear. Herein, we propose a comprehensive evaluation model of a 5G+ smart distribution network based on the combination weighting and cloud model of the improved Fuzzy Analytic Hierarchy-Entropy Weight Method (FAHP- EWM). First, we establish comprehensive evaluation indexes of a 5G+ smart distribution network from five dimensions: reliable operation, economic operation, efficient interaction, technological intelligence, and green emission reduction. Second, by introducing the principle of variance minimization, we propose a combined weighting method based on the improved FAHP-EWM to calculate the comprehensive weight, so as to reduce the defects of subjective arbitrariness and promote objectivity. Finally, a comprehensive evaluation model of 5G+ smart distribution network based on cloud model is proposed by considering the uncertainty of distribution network node information and equipment status information. The example analysis indicates that the overall operation of the 5G+ smart distribution network project is decent, and the weight value calculated by the combined weighting method is more reasonable and accurate than that calculated by the single weighting method, which verifies the effectiveness and rationality of the proposed evaluation method. Moreover, the proposed evaluation method has a certain guiding role for the large-scale application of 5G communication technology in smart distribution networks.

Risk assessment of floor water inrush based on TOPSIS combined weighting model: a case study in a coal mine, China

Risk assessment of floor water inrush based on TOPSIS combined weighting model: a case study in a coal mine, China

Comprehensive importance analysis for repairable system components based on the GO method

In order to effectively improve the reliability level of the permanent magnet synchronous motor (PMSM) drive system of electric aircraft, a component importance analysis based on the GO method for the repairable systems is proposed. Firstly, the system reliability model GO diagram is established according to the hardware schematic diagram of the PMSM drive system. Secondly, the steady-state availability and failure importance of the components are calculated. In addition, the criteria importance through intercriteria correlation (CRITIC) is adopted to determine the objective weights of steady-state availability and failure importance. The combined weighting is employed to obtain the importance of key components. Meanwhile, a system redundancy design based on the importance of components is proposed to provide data support for the design of the system. Finally, the feasibility and effectiveness of the proposed method are evaluated by an example of an electric aircraft PMSM drive system. This method provides a supporting basis for the optimization design of the entire system.

The research on priority selection of e-commerce agent operation service providers based on Fuzzy-DEMATEL, ANP combination weighting and TOPSIS analysis

In view of the comprehensive evaluation and selection of e-commerce agent service provider, this paper discusses the construction of e-commerce agent service provider selection index system. Fuzzy-Decision-Making Trial and Evaluation Laboratory (Fuzzy-DEMATEL) is selected to analyze the logical relationship and influence relationship between the selection indexes of e-commerce representative operation service providers, and the importance and relevance Analytic Network Process (ANP) network was constructed. The combined weighting method of Fuzzy-Dematel and ANP is used to calculate the mixed weight, and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method was used to complete the comprehensive ranking and selection of alternatives. Finally, the empirical analysis of M company, a toy manufacturing enterprise in central China, choosing e-commerce agent operation service provider is carried out by using the established evaluation method, and the results show that the evaluation method is effective and feasible.

A game theory enhanced domain adaptation network for mechanical fault diagnosis

Transfer learning technology has been successfully applied to address the domain adaptation (DA) problem in machinery fault diagnosis. However, the partial DA problem is more suitable for industrial applications, where the target data only covers a subset of the source classes, which makes it difficult to know where to transfer the target data. To overcome this problem, a novel game theory enhanced DA network (GT-DAN) is proposed in this paper. Based on different metrics, including the maximum mean discrepancy, Jensen–Shannon divergence and Wasserstein distance, three attention matrices are constructed to describe the distribution discrepancies between the source domain and the target domain. The optimal coordination between these attention matrices is achieved by a combined weighting based on game theory to generate the optimal probability weights, which can act as a guide to filter out the irrelevant source examples in DA. Two experiments show that the proposed GT-DAN is superior to existing methods in partial DA diagnosis performance.

Reliability Assessment of Highway Bridges Based on Combined Empowerment–TOPSIS Method

(1) In recent years, with the continuous increase of the state’s investment in infrastructure, the construction of highways and bridges has developed rapidly, which has brought great convenience to people’s lives. At the same time, with the increase of bridge service time, the reliability of bridges declines. In order to meet the requirements of sustainable development, it is necessary to accurately evaluate the reliability of bridges. However, most of the existing evaluation methods have single-weighting and one-sidedness. There are problems such as strong subjectivity and overly simple evaluation procedures. Therefore, it is urgent to establish a new scientific bridge reliability evaluation system. (2) Methods. In this paper, a bridge superstructure is taken as the research object, and the “Technical Condition Assessment Standard for Highway Bridges” (JTG/T H21-2011) is used as the criterion to establish a bridge reliability evaluation index system. The subjective and objective weights of the evaluation indicators are based on minimum discriminant information. Each evaluation indicator is combined and weighted; then, the closeness of each evaluation object to the positive ideal solution is determined according to Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). Finally, the reliability level of each evaluation object is determined. (3) Results. Reliability evaluation of the three-span superstructure of the bridge was carried out, and final reliability evaluation results of “Grade 2, Grade 2, Grade 2” were obtained, which are consistent with the actual working state of the bridge. (4) Conclusions. The evaluation results of this paper are consistent with the results obtained by the traditional AHP–Extenics method, but the evaluation model of this paper adopts combined weighting, which avoids the one-sidedness of the weighting of a single method—thus, the comprehensive weight obtained not only reflects the subjective intention of decision makers, but also reflects the objective properties of the data.

Credit Risk Evaluation of Forest Farmers under Internet Crowdfunding Mode: The Case of China’s Collective Forest Regions

To effectively quantify and control the credit risk of forest farmers under internet crowdfunding mode, the combined weighting of norm grey correlation, the improved analytic hierarchy process and empirical mode decomposition method are proposed to measure the credit risk, and the interval rough number DEMATEL method is used to analyze the credit risk factors of forest farmers. Through the calculation of comprehensive influence degree, it is concluded that the degree of investor information asymmetry, the intensity of supervision, the degree of innovation and cooperation between funders and investors are the main credit risk factors of forest farmers under internet crowdfunding mode, and a credit risk control mechanism is constructed according to the main credit risk factors to effectively improve the risk management and control level of forest farmers.

Evaluation of cabin energy consumption based on combination weighting and grey fuzzy comprehensive model

Painting is the largest energy consumption unit in ship repair enterprises, with annual electrical energy costs amounting to millions of dollars. The energy-saving model of painting business based on artificial intelligence, Internet of Vehicles (IoV) and big data technologies has become a current research hot spot. This paper takes a cargo ship of Youlian Shipyard as an example to improve the quality of special coating construction, reduce cost and increase efficiency. In the process of special coating construction, a comprehensive analysis of equipment usage in different compartments is carried out, and a compartment energy consumption analysis model based on combined weighting and Gray Fuzzy Comprehensive Evaluation is proposed. The model uses factors such as energy consumption, hours, and number of devices as evaluation indicators. Based on the fuzzy comprehensive evaluation, the gray correlation coefficients and comprehensive weights were weighted to obtain the final comprehensive evaluation results of each planning scheme, and then compare them to determine the optimal scheme. The results show that the grey fuzzy comprehensive evaluation model with combined weighting has better results than other models, and the evaluation results are scientific and reasonable. It has certain application value in multi-objective scheme optimization.

Application of Combining Weighting and Efficacy Coefficient in Cigarette Physical Quality Evaluation

Cigarettes are the ultimate consumer products of tobacco (Nicotiana tabacum L.), and the physical indexes directly affect the stability of product quality. In order to objectively evaluate the quality stability of cigarette products, a novel method combined weighting and efficacy coefficient is established to assess the stability of cigarette physical quality, and the weight calculated by the efficacy coefficient method is normalized to the comprehensive scores. Meanwhile, this method has also been used to evaluate the rationality of key parameters of the rolling machine. The results show that the comprehensive scores calculated via the combined weighting method (CWM) exhibit the satisfied linear relationship with the production qualification rate (R = 0.9190), demonstrating this CWM could organically integrate the subjective and objective weights, which also objectively consider the decision makers’ preferences as well as the inherent regulations between acquired data. In actual production, the obtained comprehensive scores can reflect the overall quality level of cigarette products as the changes of operation groups, equipment units, and operation parameters. The appropriate parameters of guide plate height and accelerator roller interval should be controlled at the range of 61~67 mm and 0.25~0.65 mm, respectively. In conclusion, these further indicate that the novel combined weighting and efficacy coefficient methods show a better superiority for objectively evaluating cigarette quality and offering evidence for parameters optimization.

LEACH Protocol Optimization Based on Weighting Strategy and the Improved Ant Colony Algorithm.

This article aims to address problems in the current clustering process of low-energy adaptive clustering hierarchy (LEACH) in the wireless sensor networks, such as strong randomness and local optimum in the path optimization. This article proposes an optimal combined weighting (OCW) and improved ant colony optimization (IACO) algorithm for the LEACH protocol optimization. First, cluster head nodes are updated via a dynamic replacement mechanism of the whole network cluster head nodes to reduce the network energy consumption. In order to improve the quality of the selected cluster head nodes, this article proposes the OCW method to dynamically change the weight according to the importance of the cluster head node in different regions, in accordance with the three impact factors of the node residual energy, density, and distance between the node and the sink node in different regions. Second, the network is partitioned and the transmission path among the clusters can be optimized by the transfer probability in IACO with combined local and global pheromone update mechanism. The efficacy of the proposed LEACH protocol optimization method has been verified with MATLAB simulation experiments.

Multi-factor coupling regulation of greenhouse environment based on comprehensive growth of cherry tomato seedlings

Environmental regulation based on crops can ensure efficient and high-quality production. However, environmental factors, such as temperature, air humidity, and light intensity, promote and restrict production during the crop growth, while complex compensation effects and feedback paths exist among these factors. In order to accurately and efficiently control the greenhouse environment for the growth of cherry tomato seedlings, a design of composite quadratic orthogonal regressive rotation with three factors and five levels was adopted. Experimental variables included temperature, relative humidity (RH), and photosynthetically active radiation (PAR). We established the response models of growth indicators (seedling index, dry matter accumulation, net photosynthetic rate, transpiration rate and chlorophyll content) to environmental multiple factors. The analytic hierarchy process (AHP) and entropy weight method were introduced to weight five indicators, and the game theory-based combined weighting method was subsequently used to obtain the final weight of each indicator. A comprehensive growth evaluation system for cherry tomato seedlings was established based on Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS), and the response model of comprehensive growth to environment multi-factor was established according to evaluation values. Also, the synergistic regulation of the environmental factors was analyzed. Results demonstrated that the optimum environment for the seedling index is consistent with that of dry matter accumulation, but different from those of other growth indicators. Furthermore, the greatest combined weight was determined for the seedling index (0.327), while chlorophyll content ranked bottom (0.118). Enhancing photosynthetically active radiation was not able to significantly promote the growth of tomato under low temperatures and humidity. Based on our results, for medium levels of photosynthetically active radiation, increasing relative humidity rather than temperature is suggested for the promotion of tomato growth during the seedling. In addition, the optimal environmental factor combination for comprehensive growth of cherry tomato seeding was a temperature of 27.6 °C, an RH of 76.1% and PAR of 396.3 μmol•m − 2•s − 1. Our results can be applied to the environmental management of greenhouse cherry tomato seedlings and can also improve energy efficiency of environmental control.

Regional Differences and Convergence of Urban-Rural Integration Development from the Perspective of Factor Flow.

Based on the panel data of thirty-one provinces in China from 2003 to 2020, we constructed an evaluation index system of urban-rural integration development level from the perspective of factor flow. The combined weighting model of GI and CRITIC were used to evaluate the regional urban-rural integration development. The coefficient of variation and panel fixed effect model was used to explore convergence, absolute convergence, and conditional convergence. The impact of capital, labor, and technology factor flow on the convergence of urban-rural integration development level was further investigated. In addition, the difference analysis in time scale and impulse response function analysis was performed to explore the regular pattern of factor flow on the convergence of urban-rural integration development. The main conclusions were as follows: first, the growth of urban-rural integration development had an absolute convergence trend and tended to conditional convergence faster. Second, the capital flow positively affected the convergence of urban-rural integration development, while labor and technology flow had a slowing effect on the convergence of urban-rural integration development at this stage. Third, the impact of factor flow on the convergence of urban-rural integration development was dissimilar during different phases. The convergence rate of urban-rural integration development after 2012 was drastically slower than before.

Concept Analysis and Implementation of Sustainable Agriculture based on Farmer Group Development and Agribusiness Patterns

This study aimed to analyze the concept and implementation of sustainable agriculture based on farmer group development and agribusiness patterns. This study uses a qualitative research type. The criteria that influence the success of sustainable agriculture include socio-cultural, economic, agricultural technology, institutions, and government policies. The resource persons in this study were farmers in the Nanggalo sub-district, amounting to 12 people. The types of data used in this study are primary data and secondary data collected through observation, literature study, and in-depth interviews. This study uses a decision-making method to determine the priority of various choices, namely the Analytical Hierarchy Process (AHP). The results of the research based on the combined opinion weighting factor matrix of all criteria indicate that the order of priority of the most important criteria according to respondents' assessment for sustainable agricultural planning in Nanggalo District, Padang city is Institutional criteria (25.05%), Social Culture (20.73%), Agricultural Technology (20.69%), Economics (18.21%), and Government Policy (15.31%).

Research on Application Effect Evaluation of Steel Box Girder Bridge Based on Combination Weighting

At present, the research on the application effect of steel box girder bridges is still only in the qualitative analysis link, and the calculation of index weights is greatly affected by personal subjective factors, and the quantitative evaluation of the application effect of steel box girder bridges has not been achieved. In this paper, we proposes a combination of subjective and objective combined weighting fuzzy evaluation model, which avoids the unreasonable problem of a single weighting method in determining the weight coefficients, and makes the weight distribution results more accurate and effective. Among them, the coefficient of variation method and the AHP method are used to calculate the subjective and objective weights of the indicators, and the linear combination calculation method is used to determine the comprehensive weights of the indicators. Then, combined with the fuzzy evaluation model, a comprehensive analysis of the application effect is carried out. Finally, the effectiveness of the combined weighting evaluation model is verified with a practical project case.

Air pollution concentration forecasting based on wavelet transform and combined weighting forecasting model

The continuous deterioration of air quality, the frequent occurrence and its following adverse effects of air pollution incidents have caused continuous public concerns. Therefore, achieving accurate prediction of air pollutants has significant role for governance efforts. In this paper, a combined weight forecasting model (CWFM) for NO2 concentration in Beijing is constructed based on three single prediction models. Firstly, the input data are decomposed by discrete wavelet transform to increase the dimensionality of the data. Secondly, DWT-LSTM, DWT-GRU and DWT-Bi-LSTM models are constructed using the wavelet decomposition results and Long short-term memory neural network (LSTM), Gated recurrent units (GRU) and Bi-directional long-short term memory neural network (Bi-LSTM), respectively, followed by comparison and contrast of the prediction results. Finally, the three single prediction models are incorporated into the combined weighted forecasting model by weight assignment. The results show that the combined weight forecasting model constructed in this paper can improve the prediction accuracy by combining the advantages of the every single prediction models, and by contrasting with any single prediction model, the combined model structure is more suitable for the prediction of NO2 concentration in Beijing.

Operation mode selection of NIMBY facility Public Private Partnership projects.

Construction of not in my back yard (NIMBY) facility Public Private Partnership (PPP) projects are feasible measures to realize sustainable urbanization. In order to ensure the smooth development of the NIMBY facility PPP projects, the problem of choosing the most suitable operation mode among many PPP modes is still scarce and unscientific. In order to select the operation mode of the PPP projects that best fits the characteristics of the project, this paper constructs the operation mode selection of the NIMBY facility PPP project. Firstly, the index system of operation mode selection of the NIMBY facility PPP project is determined. G1 subjective weighting method and information entropy objective weighting method are introduced to solve the optimal weight of each index. Grey correlation theory is used to improve TOPSIS method, and the calculation form of relative proximity degree is optimized to determine the most suitable operation mode for the project. In this paper, combined weighting and TOPSIS method are applied to the research of NIMBY facility PPP project, and the operation mode selection of NIMBY facility PPP project is established, which makes up the blank of this part. Finally, a PPP project in Qingdao, Shandong Province, China, is taken as an example to verify the applicability of the model. The effectiveness of this model was tested by comparing the results of TOPSIS method, Grey target model, Extended matter-element mode and GRA-TOPSIS. It is hoped to provide useful reference for the operation mode selection of NIMBY facility PPP project.

Two-dimensional evaluation model of electrical equipment based on combined weighting and rating algorithm

In the process of electric energy substitution, many industries have gradually replaced the traditional energy consumption equipment with new electrical ones. To avoid the disadvantage of one-sidedness in equipment evaluation and provide a more comprehensive reference for enterprises to replace equipment, a two-dimensional evaluation model composed of static and dynamic rating model is proposed in this paper based on combined weighting and rating algorithm, considering the comprehensive performance in both the inherent properties and the actual power consumption features of electrical equipment. The static and dynamic parameters related are firstly extracted, and then the weights of parameters are determined by the analytic hierarchy process (AHP) subjective weighting algorithm and principal component analysis (PCA) objective weighting algorithm. To compare the performance of different equipment more intuitively, the rank sum ratio (RSR) and technology for order preference by similarity to an ideal solution (TOPSIS) are used to rate the static and dynamic scores, respectively. Case studies for different types of electrical tea dryers in Anji, Zhejiang Province, China, show that the proposed evaluation model is more comprehensive and the rating result is more reasonable, which helps the enterprises have a more comprehensive understanding of the electrical equipment performance.

A Two-Step Stochastic Hybrid Estimation for GNSS Carrier Phase Tracking in Urban Environments

This article presents a two-step stochastic hybrid estimation (TS-SHE) algorithm for robust and accurate carrier phase tracking of global navigation satellite system (GNSS) signals in urban environments with significant power degradation and fluctuation. The proposed algorithm adaptively combines a bank of parallel Kalman filters (KFs) with different dynamic state models to cope with the nonstationarity of GNSS signals. Different from conventional approaches, including the phase lock loop (PLL), the KF, and the interacting multiple-model (IMM) method, which strongly rely on the a priori fixed signal model to ensure good tracking performance, we develop a novel stochastic filter transition strategy utilizing the information from reliable signal condition evaluation to overcome the performance degradation caused by the model mismatch in urban environments. Therein, for the first time, we use the prior information of signal fading conditions for more accurate combined weighting of all component filters. Specifically, to obtain the prior information, GNSS data are sequentially buffered and analyzed in the first step. Then, in the second step, optimized filter weights are generated, and the overall combined carrier phase is estimated. We analyze the theoretical performance of the new algorithm and show the effects of different design parameters on the performance. The primary advantages of the proposed algorithm include: 1) the ability to rapidly recover carrier phase observation when blocked signals are reacquired and 2) high accuracy in carrier phase estimation of GNSS signals corrupted by strong multipath fading. Simulation and real data experiment results show the enhanced robustness and improved accuracy of the proposed TS-SHE algorithm compared with conventional carrier phase tracking methods.

A new framework to select energy-efficient retrofit schemes of external walls: A case study

Abstract Retrofitting energy-inefficient external walls would improve the energy performance of building envelope by utilizing new insulation materials to decrease heat transfer. However, previous researches mainly based on environmental and economic considerations are still partial and could hardly provide a holistic perspective for the optimal selection of external walls retrofit techniques. To address this problem, this paper proposes a novel heterogeneous multi-criteria group decision-making (MCGDM) framework in which the ratings of schemes are described with real numbers and linguistic variables and the weights of criteria are unknown. Firstly, an evaluation index system is established covering criteria of thermal insulation property, technique, durability, and economic efficiency. Secondly, building information modeling (BIM) is utilized to determine multiple retrofit schemes and derive the heat transfer coefficient. Thirdly, after heterogeneous evaluation values are unified, a combined weighting approach is developed based on best worst method (BWM) and the similarity method before fuzzy VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR) method is applied to rank the alternatives. Fourthly, the applicability of the proposed framework is demonstrated by a case study of the external wall retrofit scheme selection in Beijing, which reveals that extruded polystyrene (XPS) and expanded polystyrene (EPS) insulation schemes are the compromise choices with aggregating index Qk of 0.0032 and 0.0967 respectively, while rock wool insulation scheme is the last option with Qk of 0.7182. The stability of ranking results is proved with the changing weight of maximum group utility, and the effectiveness of the proposed framework is verified by a comparative analysis. This study can facilitate the implementation of building envelope retrofit by providing useful guidance for selection of external wall retrofit schemes.