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To retrieve the geometric information contained in CT images, a surface reconstruction method, which is based on the similarity between the corresponding contours of adjacent sections, is presented in this paper. The correspondence of the contours of adjacent sections is determined by incorporating the topological rules and overlaps of the convex hulls of the contours. Then, the similar vertices of the corresponding contours are matched using a two‐phase strategy, consisting of overall matching followed by local matching. Dissimilar portions are extracted to construct the triangulable spatial dissimilar polygons. Finally, triangular meshes interpolating the contours are obtained by triangulating the dissimilar polygons and similar portions separately. The reconstructed surface models can be used in rapid prototyping as well as visualization. Experimental results demonstrate the validity of the method in reconstructing the surface from severe dissimilar contours.

With the function of reconstructing and promoting traditional industries in China, logistic service industry (LSI) still consumes a great deal of energy. The purpose of this paper is to empirically analyse the relationship between energy consumption of logistics and its influential factors in China, and through this, identify the most important factor and give a significant research of this factor afterwards.

Using a quantitative analysis of the industry composition of energy consumption and the structure of energy consumption in LSI, the serious condition of China's energy conservation of LSI was found. Correlated analysis and co‐integration analysis were adopted to identify how these factors affected the energy conservation of LSI and how to construct environmental logistics in China.

The paper found mileage traveled by train is the most important factor of energy consumption in LSI, while traveling miles of highway is the second. The former was negative correlation with the total of energy consumption while the latter was positive correlation.

Because of the deficiency of data in China, this research is based on the data of 30 years, which is not testified as long enough for this research. This would indicate that the conclusions of this paper are approximate values. A closer look should be taken at the effectiveness of some of the other factors suggested in the previous research on this topic.

The paper outlines ways to effectively construct environmental logistics in China which would promote the energy conservation and sustainable development of this country. Since the total consumption of energy in China accounts for a certain proportion of the world, this will benefit other countries as well.

This paper is one of the first of its kind to develop and empirically analyze the relationship between energy consumption of LSI and its influential factors in China. It uniquely contributes towards helping us find approaches to constructing China's environmental logistics and will have far‐reaching implications for other developing countries.

This article aims to discuss the binary matrix of spatial association which is suggested by Moran, and proposes a new method of the definition of the w matrix to obtain a new space‐time correlation coefficient considering the correlation of both time and space.

From the perspective of the multi‐dimension of space and time, this article proposes a new computational method of a correlation coefficient considering both temporal and spatial factors, based on the analysis of the characteristics of Moran's Global Index and Moran's Local Index. The number of patents granted in mainland China's provinces and municipalities is taken as an example of multi‐dimensional analysis.

The results of quantitative analysis using this space‐time correlation coefficient show that the outcomes calculated by this new correlation coefficient are not only highly correlated with Moran's Index, but also have advantages in analyzing the trends of both spatial and temporal indicators simultaneously, which is verified by the illustration of the algorithm.

Due to a scarcity of data in China, the algorithm is based on data for the last 20 years, which may not be long enough for this research. Although this does not reduce the value of the conclusions of this article, a closer look should be taken at the effectiveness of the new space‐time correlation coefficient in the future.

The results of space‐time correlation coefficient are highly correlated with Moran's Index. In addition, it can not only analyze the “flow” indicators in a certain period but also analyze the “stock” indicators to reflect both space and time changes. These may reflect superiority of space‐time correlation coefficient to Moran's Index.

This new correlation coefficient that considers both temporal and spatial factors and will provide a more scientific and effective tool for spatial econometric analysis in time and space changes of management on society and the economy.

The purpose of this paper is to study the saturation and nonlinear performance of magnetic field in the air gap of switched reluctance motor (SRM).

The analytical method of sub-domain combined with the saturation compensation method is used to determine the nonlinear distribution of air gap magnetic field in SRM. Also, the resolutions of the two-dimensional (2D) Laplace’s equation and Poisson’s equation in polar coordinates are used to obtain the simplified expression of magnetic flux density.

For verifying the effectiveness of analytical model, the results are compared with those obtained from the 2D finite element method (FEM). The influence of magnetic saturation is taken into account by associating the sub-domain analysis result with the nonlinear B-H properties of stator and rotor iron. The magnetic flux density in radial and tangential direction considering the saturation effect may be calculated accurately. It can be seen that one can easily determine the linear analytical results accurately, whereas it is difficult to determine the magnetic flux density with saturation influence; especially at some local positions, there is a larger difference between analytical and FE model due to the complex boundary conditions.

This paper presents the development and optimization design of high-performance SRM.

The magnetic saturation may be taken into account for the SRM and analytical models support to simulated system performance.

Recently, China has been paying increasing attention to how to improve the efficiency of the marine environment and realize a green and sustainable development of the marine economy. Consequently, the industrial structure is crucial to improving efficiency. The purpose of this paper is to introduce environmental factors into the efficiency analysis framework and explore the relationship between marine industrial structure and marine environmental efficiency.

This paper uses marine economic data under the DEA-BBC model to measure the marine environmental efficiency of provinces and cities and classifies them by cluster analysis. Then, the marine industrial structure and marine environmental efficiency are studied by an econometric model with human capital, ownership structure, land economic development level, scientific research input and government intervention degree as control variables.

The overall level of marine environmental efficiency is relatively low in China, increasing and then decreasing over the research period. The rationalization of industrial structure and scientific research input have significant promoting effects on marine environmental efficiency, while the degree of government intervention has a significant inhibiting effect. The positive effect of human capital on efficiency depends on whether it can be successfully converted into productivity. The effects of industrial structure advancement, ownership structure and land economic development level of on the marine environmental efficiency are mixed.

The results provide a theoretical and decision-making basis for China to transform and upgrade its marine industrial structure and sustainably develop the marine economy.

To construct a scientific and reasonable indicator system, it is necessary to design a set of standardized indicator primary selection and optimization inspection process. The purpose of this paper is to provide theoretical guidance and reference standards for the indicator system design process, laying a solid foundation for the application of the indicator system, by systematically exploring the expert evaluation method to optimize the index system to enhance its credibility and reliability, to improve its resolution and accuracy and reduce its objectivity and randomness.

The paper is based on system theory and statistics, and it designs the main line of “relevant theoretical analysis – identification of indicators – expert assignment and quality inspection” to achieve the design and optimization of the indicator system. First, the theoretical basis analysis, relevant factor analysis and physical process description are used to clarify the comprehensive evaluation problem and the correlation mechanism. Second, the system structure analysis, hierarchical decomposition and indicator set identification are used to complete the initial establishment of the indicator system. Third, based on expert assignment method, such as Delphi assignments, statistical analysis, t-test and non-parametric test are used to complete the expert assignment quality diagnosis of a single index, the reliability and validity test is used to perform single-index assignment correction and consistency test is used for KENDALL coordination coefficient and F-test multi-indicator expert assignment quality diagnosis.

Compared with the traditional index system construction method, the optimization process used in the study standardizes the process of index establishment, reduces subjectivity and randomness, and enhances objectivity and scientificity.

The innovation point and value of the paper are embodied in three aspects. First, the system design process of the combined indicator system, the multi-dimensional index screening and system optimization are carried out to ensure that the index system is scientific, reasonable and comprehensive. Second, the experts’ background is comprehensively evaluated. The objectivity and reliability of experts’ assignment are analyzed and improved on the basis of traditional methods. Third, aim at the quality of expert assignment, conduct t-test, non-parametric test of single index, and multi-optimal test of coordination and importance of multiple indicators, enhance experts the practicality of assignment and ensures the quality of expert assignment.

This paper aims to present the numerical models and experimental outcomes pertain to the performance of the parabolic dish concentrator system with a modified cavity-type receiver (hemispherical-shaped).

The numerical models were evolved based on two types of boundary conditions; isothermal receiver surface and non-isothermal receiver surface. For validation of the numerical models with experimental results, three statistical terms were used: mean of absolute deviation, R² and root mean square error.

The thermal efficiency of the receiver values obtained using the numerical model with a non-isothermal receiver surface found agreeing well with experimental results. The numerical model with non-isothermal surface boundary condition exhibited more accurate results as compared to that with isothermal surface boundary condition. The receiver heat loss analysis based on the experimental outcomes is also carried out to estimate the contributions of various modes of heat transfer. The losses by radiation, convection and conduction contribute about 27.47%, 70.89% and 1.83%, in the total receiver loss, respectively.

An empirical correlation based on experimental data is also presented to anticipate the effect of studied parameters on the receiver collection efficiency. The anticipations may help to adopt the technology for practical use.

The developed models would help to design and anticipating the performance of the dish concentrator system with a modified cavity receiver that may be used for applications e.g. power generation, water heating, air-conditioning, solar cooking, solar drying, energy storage, etc.

The originality of this manuscript comprising presenting a differential-mathematical analysis/modeling of hemispherical shaped modified cavity receiver with non-uniform surface temperature boundary condition. It can estimate the variation of temperature of heat transfer fluid (water) along with the receiver height, by taking into account the receiver cavity losses by means of radiation and convection modes. The model also considers the radiative heat exchange among the internal ring-surface elements of the cavity.

Cross operation is a common operation method in the building construction process nowadays. Due to the crossover, each other's operations are disturbed, and risks also interact. This superimposed relationship of risks is worthy of attention. The study aims to develop a model for analyzing cross-working risks. This model can quantify the correlation of various risk factors.

The concept of cross operation and the cross types involved are clarified. The risk factors were extracted from cross-operation accidents. The association rule mining (ARM) was used to analyze the results of various cross-types accidents. With the help of visualization tools, the intensity distribution and correlation path of the relationship between each factor were obtained. A complete cross-operation risk analysis model was established.

The application of ARM method proves that there are obvious risk correlation deviations in different types of cross operations. A high-frequency risk common to all cross operations is on-site safety inspection and process supervision, but the subsequent problems are different. Cutting off the high-lift risk chain timely according to the results obtained by ARM can reduce or eliminate the danger of high-frequency risk factors.

This is the first systematic analysis of cross-work risk in the construction. The study determined the priority of risk management. The results contribute to targeted cross-work control to reduce accidents caused by cross-work.