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An approach for evaluating the impact of an intermittent renewable energy source on transmission expansionplanning

Rongrit CHATTHAWORN,Surachai CHAITUSANEY

《信息与电子工程前沿（英文）》 2015年 第16卷 第10期   页码 871-882 doi: 10.1631/FITEE.1500049

摘要： We propose a new robust optimization approach to evaluate the impact of an intermittent renewable energy source on transmission expansion planning (TEP). The objective function of TEP is composed of the investment cost of the transmission line and the operating cost of conventional generators. A method to select suitable scenarios representing the intermittent renewable energy generation and loads is proposed to obtain robust expansion planning for all possible scenarios. A meta-heuristic algorithm called adaptive tabu search (ATS) is employed in the proposed TEP. ATS iterates between the main problem, which minimizes the investment and operating costs, and the subproblem, which minimizes the cost of power generation from conventional generators and curtailments of renewable energy generation and loads. The subproblem is solved by nonlinear programming (NLP) based on an interior point method. Moreover, the impact of an intermittent renewable energy source on TEP was evaluated by comparing expansion planning with and without consideration of a renewable energy source. The IEEE Reliability Test System 79 (RTS 79) was used for testing the proposed method and evaluating the impact of an intermittent renewable energy source on TEP. The results show that the proposed robust optimization approach provides a more robust solution than other methods and that the impact of an intermittent renewable energy source on TEP should be considered.

关键词： Adaptive tabu search     Renewable energy generation     Robust optimization     Transmission expansion planning    

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Integrated transmission and generation planning model in a deregulated environment

Enrique B. CEDE?O, Sant ARORA

《能源前沿（英文）》 2013年 第7卷 第2期   页码 182-190 doi: 10.1007/s11708-013-0256-8

摘要： After the deregulation of the Power Sector in the U.S., planning for generation and transmission capacities is decentralized. There is, however, still need for the long term integrated planning of generation and transmission capacities at the macro level, since these two sectors must operate in a coordinated manner. This paper presents a model for integrating generation and transmission expansion planning to identify an indicative expansion plan for the total sector at the macro level. The argument for an integrated model is supported using evidence from integrated planning efforts in real life systems. The application of the proposed model is illustrated using an example that requires expansion of generation and transmission capacities over three regions in a deregulated power system. The example considers that addition of generating capacity should come from renewable sources. The test results show the potential cost saving from integrated planning.

关键词： integrated planning     indicative plans     power generation     transmission     deregulation    

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大规模海上风电并网送出策略研究

张占奎,石文辉,屈姬贤,白宏

《中国工程科学》 2021年 第23卷 第4期   页码 182-190 doi: 10.15302/J-SSCAE-2021.04.021

摘要：

海上风电是世界风电未来发展的重要方向，经济高效地解决大规模海上风电并网问题是海上风电建设面临的核心挑战之一。本文总结了世界海上风电的发展现状、我国海上风电发展环境及行业进展，归纳了海上风电的全球性发展趋势；从海上风电场单场典型并网、大规模海上风电集群送出两类典型情景出发，梳理了相关技术特征及其代表性应用。在凝练我国海上风电并网送出面临问题的基础上，提出了我国海上风电并网的整体发展策略，并就两类典型情景的送出方案开展适应性分析和评价。研究建议，摸清资源储量、确定统一规划理念，加强自主创新、突破并网关键技术，完善体制机制、确保高质量发展，加强国际交流、促进国际产业合作，以此谋划和建设一流水平、契合国情的海上风电并网送出工程，更好支撑我国能源转型发展。

关键词： 海上风电     集群     并网送出     规划方案     适应性分析    

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A MATLAB code for the material-field series-expansion topology optimization method

《机械工程前沿（英文）》 2021年 第16卷 第3期   页码 607-622 doi: 10.1007/s11465-021-0637-3

摘要： This paper presents a MATLAB implementation of the material-field series-expansion (MFSE) topo-logy optimization method. The MFSE method uses a bounded material field with specified spatial correlation to represent the structural topology. With the series-expansion method for bounded fields, this material field is described with the characteristic base functions and the corresponding coefficients. Compared with the conventional density-based method, the MFSE method decouples the topological description and the finite element discretization, and greatly reduces the number of design variables after dimensionality reduction. Other features of this method include inherent control on structural topological complexity, crisp structural boundary description, mesh independence, and being free from the checkerboard pattern. With the focus on the implementation of the MFSE method, the present MATLAB code uses the maximum stiffness optimization problems solved with a gradient-based optimizer as examples. The MATLAB code consists of three parts, namely, the main program and two subroutines (one for aggregating the optimization constraints and the other about the method of moving asymptotes optimizer). The implementation of the code and its extensions to topology optimization problems with multiple load cases and passive elements are discussed in detail. The code is intended for researchers who are interested in this method and want to get started with it quickly. It can also be used as a basis for handling complex engineering optimization problems by combining the MFSE topology optimization method with non-gradient optimization algorithms without sensitivity information because only a few design variables are required to describe relatively complex structural topology and smooth structural boundaries using the MFSE method.

关键词： MATLAB implementation     topology optimization     material-field series-expansion method     bounded material field     dimensionality reduction    

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Assessment of bridge expansion joints using long-term displacement measurement under changing environmental

Youliang DING, Aiqun LI

《结构与土木工程前沿（英文）》 2011年 第5卷 第3期   页码 374-380 doi: 10.1007/s11709-011-0122-x

摘要： This paper addresses the problem of condition assessment of bridge expansion joints using long-term measurement data under changing environmental conditions. The effects of temperature, traffic loading and wind on the expansion joint displacements are analyzed and interpreted, which reveal that measured displacements are observed to increase with an increase in temperature and to decrease with increased traffic loading, while the correlation between displacement and wind speed is very weak. Two regression models are developed to simulate the varying displacements under the changes in temperature and traffic loadings. Based on these models, the effects of the environmental conditions are removed to obtain the normalized displacement. Statistical process control using mean value control charts is further used to detect damage to the bridge expansion joints. The results reveal that the proposed method had a good capability for detecting the damage-induced 1.0% variances of the annual changes in the expansion joint displacements.

关键词： structural health monitoring     displacement     expansion joint     temperature effect     wind effect     traffic loading     statistical process control     suspension bridge    

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Achieving desired nodal lines in freely vibrating structures via material-field series-expansion topology

《机械工程前沿（英文）》 2023年 第18卷 第3期 doi: 10.1007/s11465-023-0758-y

摘要： Accurately controlling the nodal lines of vibrating structures with topology optimization is a highly challenging task. The major difficulties in this type of problem include a large number of design variables, the highly nonlinear and multi-peak characteristics of iteration, and the changeable orders of eigenmodes. In this study, an effective material-field series-expansion (MFSE)-based topology optimization design strategy for precisely controlling nodal lines is proposed. Here, two typical optimization targets are established: (1) minimizing the difference between structural nodal lines and their desired positions, and (2) keeping the position of nodal lines within the specified range while optimizing certain dynamic performance. To solve this complex optimization problem, the structural topology of structures is first represented by a few design variables on the basis of the MFSE model. Then, the problems are effectively solved using a sequence Kriging-based optimization algorithm without requiring design sensitivity analysis. The proposed design strategy inherently circumvents various numerical difficulties and can effectively obtain the desired vibration modes and nodal lines. Numerical examples are provided to validate the proposed topology optimization models and the corresponding solution strategy.

关键词： nodal line     topology optimization     structural dynamics design     material-field series-expansion    

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Choosing configurations of transmission line tower grounding by back flashover probability value

Dmitry KUKLIN

《能源前沿（英文）》 2016年 第10卷 第2期   页码 213-226 doi: 10.1007/s11708-016-0398-6

摘要： There is a considerable number of works devoted to electrical characteristics of grounding. These characteristics are important in general. However, in application to grounding of transmission line towers they are not enough to determine what grounding construction is preferable in some particular case, because these characteristics are calculated or measured apart from the grounded object, and only limited number of current (or voltage) source waveforms is used. This paper indicates reasons in favor of the fact that to choose the optimum design of grounding, the calculation model should include the tower as it is. The probability of back flashover, which provides both qualitative and quantitative estimate of the grounding structure efficiency, can be taken as the criterion for the grounding design. The insulation flashover probability is calculated on the basis of engineering method, which evaluates breakdown strength of insulation for nonstandard waveshapes, and probability data on lightning currents. Different approaches are examined for identifying the back flashover probability, as not only amplitudes but also other parameters can be taken into account. Finite-difference time-domain method is used for calculations of transients. It is found that lightning current waveform can greatly influence calculated back flashover probability value.

关键词： grounding     transmission line tower     back flashover probability     FDTD method    

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Numerical simulation of sudden-expansion two-phase flows with two-scale second-order moment particle

ZENG Zhuoxiong, HAN Shoulei, ZHOU Lixing

《能源前沿（英文）》 2007年 第1卷 第2期   页码 202-206 doi: 10.1007/s11708-007-0026-6

摘要： A two-scale second-order moment particle turbulence model is developed, based on the concept of particle large-scale fluctuation due to turbulence and particle small-scale fluctuation due to collision. The model is employed to simulate gas-particle flows in a sudden-expansion chamber. Simulation results are compared with the experimental results and with those obtained by the single-scale second-order moment two-phase turbulence model. It is shown that the two-scale model is with higher calculating accuracy than the single-scale model.

关键词： gas-particle     single-scale second-order     large-scale fluctuation     second-order     sudden-expansion    

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硝酸铵膨化理论研究

吕春绪

《中国工程科学》 2001年 第3卷 第9期   页码 58-63

摘要：

描述了硝酸铵膨化过程，计算与测定了其物理化学参数，研究了膨化过程的影响因素，并给出了膨化过程可能的机理。

关键词： 膨化硝酸铵     膨化理论     物理化学参数     影响因素    

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Modelling autogenous expansion for magnesia concrete in arch dams

JIN Feng, LUO Xiaoqing, ZHANG Chuhan, ZHANG Guoxin

《结构与土木工程前沿（英文）》 2008年 第2卷 第3期   页码 211-218 doi: 10.1007/s11709-008-0025-7

摘要： Magnesia Concrete is a kind of expansive concrete used in Chinese hydraulic engineering more and more widely. To evaluate the effects of autogenous expansion on the stresses of arch dams, a simple model of autogenous expansion for Magnesia Concrete in dam engineering is presented. This model is based on three assumptions: 1) the total amount of autogenous expansion of Magnesia Concrete is related only to the properties of materials and mixing of concrete; 2) the autogenous expansion of Magnesia Concrete is irreversible due to the irreversibility of hydration reaction of Magnesia in the concrete; 3) the autogenous expansion strain rates of Magnesia Concrete bear a relation between temperature and residual Magnesia per unit volume of concrete. The model is verified by some experimental data of autogenous expansion of Magnesia Concrete and field-measured data of an arch dam in China. Embedded into finite element arch dam simulation software, this model is employed to simulate the effects of autogenous expansion of Magnesia Concrete in hydraulic engineering.

关键词： field-measured     irreversibility     temperature     irreversible     element arch    

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燕山石化公司乙烯装置66×104t/a扩能改造方案的研究与决策

曹湘洪

《中国工程科学》 2003年 第5卷 第11期   页码 34-46

摘要：

燕山石化公司30×104t/a乙烯装置1994年完成第一次扩能至45×104t/a的改造后，仍存在原料灵活性差、能耗高、与同期建设的乙烯装置比规模偏小等问题。以全面提高技术水平、降低能耗、增加原料灵活性、尽可能扩大生产能力为目标，充分考虑方案的可实施性、实施时的安全性、实施后的可操作性及方案的先进性和经济性，对装置技术改造的方案进行了比选研究。经改造，实现了生产能力扩大到66×104t/a的目标，实际可达71×104t/a，装置能耗明显下降，石脑油、轻柴油、重柴油、加氢裂化尾油均可作为乙烯原料。在世界上，首次在乙烯装置中采用混合冷剂制冷技术和碳三催化精馏加氢技术并获得成功，对世界乙烯工业技术进步有推动作用。

关键词： 乙烯     装置     扩能     方案     研究    

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Recent transmission of Mycobacterium tuberculosis in China: the implication of molecular epidemiology

null

《医学前沿（英文）》 2018年 第12卷 第1期   页码 76-83 doi: 10.1007/s11684-017-0609-5

摘要：

Tuberculosis (TB) has remained an ongoing concern in China. The national scale-up of the Directly Observed Treatment, Short Course (DOTS) program has accelerated the fight against TB in China. Nevertheless, many challenges still remain, including the spread of drug-resistant strains, high disease burden in rural areas, and enormous rural-to-urban migrations. Whether incident active TB represents recent transmission or endogenous reactivation has helped to prioritize the strategies for TB control. Evidence from molecular epidemiology studies has delineated the recent transmission of ( ) strains in many settings. However, the transmission patterns of TB in most areas of China are still not clear. Studies carried out to date could not capture the real burden of recent transmission of the disease in China because of the retrospective study design, incomplete sampling, and use of low-resolution genotyping methods. We reviewed the implementations of molecular epidemiology of TB in China, the estimated disease burden due to recent transmission of strains, the primary transmission of drug-resistant TB, and the evaluation of a feasible genotyping method of strains in circulation.

关键词： tuberculosis     recent transmission     molecular epidemiology     China    

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Lagrangian simulation of deposition of CO gas-solid sudden expansion flow

HUANG Dongping, DING Guoliang, QUACK Hans

《能源前沿（英文）》 2008年 第2卷 第2期   页码 216-221 doi: 10.1007/s11708-008-0032-3

摘要： Freezing and blockage resulting from the deposition of solid CO formed because of sudden expansion of the downstream pipe during the release of CO through safety valves, will endanger the protected equipment. To overcome this problem, the characteristics of the CO gas-solid sudden expansion flow are studied by using the disperse Lagrangian model. A comparison of the calculated deposition of the solid CO with the experimental results shows that they are in reasonable agreement. The simulation results show that the size of the solid CO formed should not be in the range of 0.04–0.07 mm ( number 3.2–9.8). This can be achieved by using an appropriate flow cross section of the safety valve.

关键词： comparison     gas-solid     downstream     blockage     Lagrangian    

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Antibiotic resistome mostly relates to bacterial taxonomy along a suburban transmission chain

《环境科学与工程前沿（英文）》 2022年 第16卷 第3期 doi: 10.1007/s11783-021-1466-7

摘要：

• The α-diversities of resistome were lower in manure and compost than in soils.

关键词： Antibiotic resistance genes     Resistome     Bacterial taxonomy     Transmission chain    

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Planet position errors in planetary transmission: Effect on load sharing and transmission error

Miguel IGLESIAS, Alfonso FERNáNDEZ, Ana DE-JUAN, Ramón SANCIBRIáN, Pablo GARCíA

《机械工程前沿（英文）》 2013年 第8卷 第1期   页码 80-87 doi: 10.1007/s11465-013-0362-7

摘要：

In this paper an advanced model of spur gear transmissions developed by the authors is used to study the influence of carrier planet pin hole position errors on the behaviour of the transmission. The model, initially conceived for external gear modeling, has been extended with internal meshing features, and thus increasing its capabilities to include planetary transmission modeling. The new features are presented, along with the summary of the model general approach. The parameters and characteristics of the planetary transmission used in the paper are introduced. The influence of carrier planet pin hole position errors on the planet load sharing is studied, and several static cases are given as examples in order to show the ability of the model. Tangential and radial planet pin hole position errors are considered independently, and the effect of the load level is also taken into account. It is also given attention to the effect on the transmission error of the transmission. Two different configurations for the planetary transmission are used, attending to the fixed or floating condition of the sun, and the differences in terms of load sharing ratio are shown.

关键词： gear     planetary     epicyclic     transmission     load sharing     transmission error    

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标题 作者 时间 类型 操作

An approach for evaluating the impact of an intermittent renewable energy source on transmission expansionplanning

Rongrit CHATTHAWORN,Surachai CHAITUSANEY

期刊论文

Integrated transmission and generation planning model in a deregulated environment

Enrique B. CEDE?O, Sant ARORA

期刊论文

大规模海上风电并网送出策略研究

张占奎,石文辉,屈姬贤,白宏

期刊论文

A MATLAB code for the material-field series-expansion topology optimization method

期刊论文

Assessment of bridge expansion joints using long-term displacement measurement under changing environmental

Youliang DING, Aiqun LI

期刊论文

Achieving desired nodal lines in freely vibrating structures via material-field series-expansion topology

期刊论文

Choosing configurations of transmission line tower grounding by back flashover probability value

Dmitry KUKLIN

期刊论文

Numerical simulation of sudden-expansion two-phase flows with two-scale second-order moment particle

ZENG Zhuoxiong, HAN Shoulei, ZHOU Lixing

期刊论文

硝酸铵膨化理论研究

吕春绪

期刊论文

Modelling autogenous expansion for magnesia concrete in arch dams

JIN Feng, LUO Xiaoqing, ZHANG Chuhan, ZHANG Guoxin

期刊论文

燕山石化公司乙烯装置66×104t/a扩能改造方案的研究与决策

曹湘洪

期刊论文

Recent transmission of Mycobacterium tuberculosis in China: the implication of molecular epidemiology

null

期刊论文

Lagrangian simulation of deposition of CO gas-solid sudden expansion flow

HUANG Dongping, DING Guoliang, QUACK Hans

期刊论文

Antibiotic resistome mostly relates to bacterial taxonomy along a suburban transmission chain

期刊论文

Planet position errors in planetary transmission: Effect on load sharing and transmission error

Miguel IGLESIAS, Alfonso FERNáNDEZ, Ana DE-JUAN, Ramón SANCIBRIáN, Pablo GARCíA

期刊论文