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Analysis of the current situation of environmental policy of China and establishment of distributed environmental

Chaoyang FU,Wangfeng LI

《环境科学与工程前沿（英文）》 2015年 第9卷 第2期   页码 310-316 doi: 10.1007/s11783-014-0658-9

摘要： In this study, China’s current macro-environmental policies as well as their implementation and management tools are analyzed. By using the basic economic methodology, detailed studies are conducted focusing on the implementation effect of contemporary China’s typical environmental policy of the total pollutant discharge quantity control type, and also the two types of environmental management tools are compared from the perspective of implementation costs and policy uncertainty. By introduction of distributed management tools into the implementation of environmental policies, market-oriented means and the methods of economic analysis are introduced into environmental policy decision-making mechanisms, which could afford a new method for changing the current relatively low efficiency of environmental policy, solving the problem of “government failure” in environmental policy implementation, and providing a new way to make environmental policy system more flexible and more efficient. It is of great practical significance to solve China's current structural, complex and accumulative environmental problems.

关键词： environmental policy     distributed environment policy     distributed parameter model     lumped parameter model    

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Predictor-corrector algorithm for solving quasi-separated-flow and transient distributed-parameter model

Ping ZHANG, Guoliang DING

《能源前沿（英文）》 2010年 第4卷 第4期   页码 535-541 doi: 10.1007/s11708-010-0113-y

摘要： The successive sub?stitution (SS) method is a suitable approach to solving the transient distributed-parameter model for heat exchangers. However, this method must be enhanced because its convergence heavily depends on the iterative initial pressure. When the iterative initial pressure is improperly assigned, the calculated flow rates become negative values, causing the state parameters to exhibit negative values as well. Therefore, a predictor-corrector algorithm (PCA) is proposed to improve the convergence of the SS method. A predictor is developed to determine an appropriate iterative initial pressure. Total fluid mass is adopted as the convergence criterion of pressure iteration instead of outlet flow rate as is done in the SS method. Convergence analysis and case study of the PCA and SS method are conducted, which show that the PCA has better convergence than the SS method under the same working conditions.

关键词： algorithm     convergence     heat exchanger     modeling     transient    

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Shallow foundation response variability due to soil and model parameter uncertainty

Prishati RAYCHOWDHURY,Sumit JINDAL

《结构与土木工程前沿（英文）》 2014年 第8卷 第3期   页码 237-251 doi: 10.1007/s11709-014-0242-1

摘要： Geotechnical uncertainties may play crucial role in response prediction of a structure with substantial soil-foundation-structure-interaction (SFSI) effects. Since the behavior of a soil-foundation system may significantly alter the response of the structure supported by it, and consequently several design decisions, it is extremely important to identify and characterize the relevant parameters. Moreover, the modeling approach and the parameters required for the modeling are also critically important for the response prediction. The present work intends to investigate the effect of soil and model parameter uncertainty on the response of shallow foundation-structure systems resting on dry dense sand. The SFSI is modeled using a beam-on-nonlinear-winkler-foundation (BNWF) concept, where soil beneath the foundation is assumed to be an assembly of discrete, nonlinear elements composed of springs, dashpots and gap elements. The sensitivity of both soil and model input parameters on shallow foundation responses are investigated using first-order second-moment (FOSM) analysis and Monte Carlo simulation through Latin hypercube sampling technique. It has been observed that the degree of accuracy in predicting the responses of the shallow foundation is highly sensitive soil parameters, such as friction angle, Poisson’s ratio and shear modulus, rather than model parameters, such as stiffness intensity ratio and spring spacing; indicating the importance of proper characterization of soil parameters for reliable soil-foundation response analysis.

关键词： shallow foun dation     sensitivity analysis     centrifuge data     first-order-second-moment (FOSM) method     parameter uncertainty    

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An operating state estimation model for integrated energy systems based on distributed solution

Dengji ZHOU, Shixi MA, Dawen HUANG, Huisheng ZHANG, Shilie WENG

《能源前沿（英文）》 2020年 第14卷 第4期   页码 801-816 doi: 10.1007/s11708-020-0687-y

摘要： In view of the disadvantages of the traditional energy supply systems, such as separate planning, separate design, independent operating mode, and the increasingly prominent nonlinear coupling between various sub-systems, the production, transmission, storage and consumption of multiple energy sources are coordinated and optimized by the integrated energy system, which improves energy and infrastructure utilization, promotes renewable energy consumption, and ensures reliability of energy supply. In this paper, the mathematical model of the electricity-gas interconnected integrated energy system and its state estimation method are studied. First, considering the nonlinearity between measurement equations and state variables, a performance simulation model is proposed. Then, the state consistency equations and constraints of the coupling nodes for multiple energy sub-systems are established, and constraints are relaxed into the objective function to decouple the integrated energy system. Finally, a distributed state estimation framework is formed by combining the synchronous alternating direction multiplier method to achieve an efficient estimation of the state of the integrated energy system. A simulation model of an electricity-gas interconnected integrated energy system verifies the efficiency and accuracy of the state estimation method proposed in this paper. The results show that the average relative errors of voltage amplitude and node pressure estimated by the proposed distributed state estimation method are only 0.0132% and 0.0864%, much lower than the estimation error by using the Lagrangian relaxation method. Besides, compared with the centralized estimation method, the proposed distributed method saves 5.42 s of computation time. The proposed method is more accurate and efficient in energy allocation and utilization.

关键词： integrated energy system     state estimation     electricity-gas coupling energy system     nonlinear coupling     distributed solution    

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Fuzzy stochastic long-term model with consideration of uncertainties for deployment of distributed energy

Iraj AHMADIAN,Oveis ABEDINIA,Noradin GHADIMI

《能源前沿（英文）》 2014年 第8卷 第4期   页码 412-425 doi: 10.1007/s11708-014-0315-9

摘要： This paper presents a novel modified interactive honey bee mating optimization (IHBMO) base fuzzy stochastic long-term approach for determining optimum location and size of distributed energy resources (DERs). The Monte Carlo simulation method is used to model the uncertainties associated with long-term load forecasting. A proper combination of several objectives is considered in the objective function. Reduction of loss and power purchased from the electricity market, loss reduction in peak load level and reduction in voltage deviation are considered simultaneously as the objective functions. First, these objectives are fuzzified and designed to be comparable with each other. Then, they are introduced into an IHBMO algorithm in order to obtain the solution which maximizes the value of integrated objective function. The output power of DERs is scheduled for each load level. An enhanced economic model is also proposed to justify investment on DER. An IEEE 30-bus radial distribution test system is used to illustrate the effectiveness of the proposed method.

关键词： component     distributed energy resources     fuzzy optimization     loss reduction     interactive honey bee mating optimization (IHBMO)     voltage deviation reduction     stochastic programming    

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Kinematic Model Building and Servo Parameter Identification of 3-HSS Parallel Mechanism

YANG Zhi-yong, WU Jiang, HUANG Tian, NI Yan-bing

《机械工程前沿（英文）》 2006年 第1卷 第1期   页码 60-66 doi: 10.1007/s11465-005-0019-2

摘要：

Aiming at a parallel mechanism with three degrees of freedom, a method for dynamic model building and the parameter identification of its servosystem is presented. First, the reverse solution models of position, velocity, and acceleration of parallelogram branch structure are deduced, and then, its dynamic model of a rigid body is set up by using the virtual work principle. Based on the above model, a method to identify the servo parameter of the parallel mechanism is put up. In this method, the triangle-shaped input with variable frequency is adopted to offset the disadvantages of pseudorandom number sequence in parameter identification, such as dramatically changing the vibration amplitude of the motor, easily impacting the motor that results in its velocity loop to easily open, and so on. Moreover, the rotary inertia can also be identified by the additive mass. The abovementioned data will lay a solid foundation for the optimum performance of the system in the whole workspace.

关键词： building     acceleration     additive     workspace     optimum performance    

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Shear-flexural strength mechanical model for the design and assessment of reinforced concrete beams subjectedto point or distributed loads

Antonio MARÍ,Antoni CLADERA,Jesús BAIRÁN,Eva OLLER,Carlos RIBAS

《结构与土木工程前沿（英文）》 2014年 第8卷 第4期   页码 337-353 doi: 10.1007/s11709-014-0081-0

摘要： A mechanical model recently developed for the shear strength of slender reinforced concrete beams with and without shear reinforcement is presented and extended to elements with uniformly distributed loads, specially focusing on practical design and assessment in this paper. The shear strength is considered to be the sum of the shear transferred by the concrete compression chord, along the crack, due to residual tensile and frictional stresses, by the stirrups and, if they exist, by the longitudinal reinforcement. Based on the principles of structural mechanics simple expressions have been derived separately for each shear transfer action and for their interaction at ultimate limit state. The predictions of the model have been compared to those obtained by using the EC2, MC2010 and ACI 318-08 provisions and they fit very well the available experimental results from the recently published ACI-DAfStb databases of shear tests on slender reinforced concrete beams with and without stirrups. Finally, a detailed application example has been presented, obtaining each contributing component to the shear strength and the assumed shape and position of the critical crack.

关键词： shear strength     mechanical model     reinforced concrete     design     assessment     shear tests    

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Probabilistic model for vessel-bridge collisions in the Three Gorges Reservoir

Bo GENG , Hong WANG , Junjie WANG ,

《结构与土木工程前沿（英文）》 2009年 第3卷 第3期   页码 279-285 doi: 10.1007/s11709-009-0044-z

摘要： Based on a field observation on vessel transit path of three bridges over the Yangtze River in the Three Gorges Reservoir, and an analysis of the geometric probabilistic model of transiting vessels in collision probability calculation, the aberrancy angle and vessel velocity probabilistic model related with impact force, a probabilistic model is established and also verified by goodness-of-fit test. The vessel transit path distribution can be expressed by the normal distribution model. For the Three Gorges Reservoir, the mean and standard deviation adopt 0.2 and 0.1, respectively ( is the channel width). The aberrancy angle distribution of vessels accepts maximum I distribution model, and its distribution parameters can be taken as 0.314 and 4.354. The velocity distribution of up-bound and down-bound vessels can also be expressed by the normal distribution model.

关键词： vessel-bridge collision     probabilistic model     parameter statistics    

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Modular architecture model of CSCD system

Hongxue XU, Hong ZHENG, Xiuying GUO

《机械工程前沿（英文）》 2010年 第5卷 第4期   页码 470-475 doi: 10.1007/s11465-010-0119-5

摘要： A modular architecture model of a computer-supported collaborative design (CSCD) system is proposed on the basis of the hierarchical structure characteristics of a distributed collaborative design system and advanced component object technology. The model mainly regards the module as the core organizing and managing design objects and uses the common object request broker architecture (CORBA) specifications as an interactive platform to achieve object communication. The browser/server computing model deals with the remote heterogeneous collaborative design problem. Product design strategies and mechanisms for collaborative design are separated to facilitate the application of distributed collaborative design environment for quick implementation. The open design framework for CSCD system developers can support the implementation of distributed collaborative design to improve product design speed and reduce product development time. The modular CSCD system (MCSCDS) model and its implementation are achieved in the modular CSCD, a prototype system.

关键词： computer-supported cooperative work (CSCW)     computer-supported collaborative design (CSCD)     distributed system     component object technology     modular architecture model    

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Performance design of a cryogenic air separation unit for variable working conditions using the lumped parametermodel

Jinghua XU, Tiantian WANG, Qianyong CHEN, Shuyou ZHANG, Jianrong TAN

《机械工程前沿（英文）》 2020年 第15卷 第1期   页码 24-42 doi: 10.1007/s11465-019-0558-6

摘要： Large-scale cryogenic air separation units (ASUs), which are widely used in global petrochemical and semiconductor industries, are being developed with high operating elasticity under variable working conditions. Different from discrete processes in traditional machinery manufacturing, the ASU process is continuous and involves the compression, adsorption, cooling, condensation, liquefaction, evaporation, and distillation of multiple streams. This feature indicates that thousands of technical parameters in adsorption, heat transfer, and distillation processes are correlated and merged into a large-scale complex system. A lumped parameter model (LPM) of ASU is proposed by lumping the main factors together and simplifying the secondary ones to achieve accurate and fast performance design. On the basis of material and energy conservation laws, the piecewise-lumped parameters are extracted under variable working conditions by using LPM. Takagi–Sugeno (T–S) fuzzy interval detection is recursively utilized to determine whether the critical point is detected or not by using different thresholds. Compared with the traditional method, LPM is particularly suitable for “rough first then precise” modeling by expanding the feasible domain using fuzzy intervals. With LPM, the performance of the air compressor, molecular sieve adsorber, turbo expander, main plate-fin heat exchangers, and packing column of a 100000 Nm O /h large-scale ASU is enhanced to adapt to variable working conditions. The designed value of net power consumption per unit of oxygen production (kW/(Nm O )) is reduced by 6.45%.

关键词： performance design     air separation unit (ASU)     lumped parameter model (LPM)     variable working conditions     T–S fuzzy interval detection    

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Multi-timescale optimization scheduling of interconnected data centers based on model predictive control

《能源前沿（英文）》 doi: 10.1007/s11708-023-0912-6

摘要： With the promotion of “dual carbon” strategy, data center (DC) access to high-penetration renewable energy sources (RESs) has become a trend in the industry. However, the uncertainty of RES poses challenges to the safe and stable operation of DCs and power grids. In this paper, a multi-timescale optimal scheduling model is established for interconnected data centers (IDCs) based on model predictive control (MPC), including day-ahead optimization, intraday rolling optimization, and intraday real-time correction. The day-ahead optimization stage aims at the lowest operating cost, the rolling optimization stage aims at the lowest intraday economic cost, and the real-time correction aims at the lowest power fluctuation, eliminating the impact of prediction errors through coordinated multi-timescale optimization. The simulation results show that the economic loss is reduced by 19.6%, and the power fluctuation is decreased by 15.23%.

关键词： model predictive control     interconnected data center     multi-timescale     optimized scheduling     distributed power supply     landscape uncertainty    

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Analysis of catchment evapotranspiration at different scales using bottom-up and top-down approaches

Xiangyu XU, Dawen YANG,

《结构与土木工程前沿（英文）》 2010年 第4卷 第1期   页码 65-77 doi: 10.1007/s11709-010-0002-9

摘要： Physically-based hydrological models are used to predict catchment water balance through detailed simulation of hydrological processes at small temporal and spatial scales. However, annual catchment water balance can also be easily and simply predicted using lumped conceptual model. Comparison between physically-based hydrological models and lumped conceptual models can help us understand the dominant factors on catchment water balance at different scales. In this paper, a distributed physically-based hydrological model (i.e., bottom-up approach) and a simple water-energy balance model (i.e., top-down approach) are used to predict actual evapotranspiration in nine sub-catchments, and the whole basin of the Luan River in northern China. Both simulations give very close values of annual evapotranspiration and show the same complementary relationship between actual and potential evapotranspiration at annual time scale. From the analysis at different time scales through comparison of the top-down and the bottom-up methods, it is shown that the annual catchment evapotranspiration is controlled mainly by annual precipitation and potential evapotranspiration, and the variability of soil water and vegetation becomes more important at a smaller time scale in the study areas. It is also known that the relationship between potential and actual evapotranspiration shows a highly nonlinear relationship at the annual and catchment scale but can be simplified to a linear relationship at hourly temporal and hillslope scales, which is commonly used in the physically-based hydrological models.

关键词： catchment evapotranspiration     distributed hydrological model     water-energy balance model     top-down and bottom-up approaches    

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大数据的分布式机器学习的策略与原则 Review

Eric P. Xing,Qirong Ho,Pengtao Xie,Dai Wei

《工程（英文）》 2016年 第2卷 第2期   页码 179-195 doi: 10.1016/J.ENG.2016.02.008

摘要：

大数据的发展已经引领了对能够学习包含数百万至数十亿参数的复杂模型的机器学习系统的新需求，以保证足够的能力来消化海量的数据集，提供强大的预测分析（如高维潜特征、中介表示和决策功能）。为了在这样的尺度上，在成百上千台的分布式机器集群中运行机器学习算法，关键往往是要投入显著的工程性的努力——有人可能会问，这样的工程是否还属于机器学习的研究领域？考虑到如此“大”的机器学习系统可以极大地从根植于机器学习的统计和算法的理解中受益——因此，机器学习的研究人员应该不会回避这样的系统设计——我们讨论了一系列从我们近来对工程尺度的机器学习解决方案的研究中提炼的原则和策略。这些原则和策略从机器学习的应用连续跨越到它的工程和理论研究，以及大型机器学习的系统和架构的发展，目标是了解如何使其有效、广泛地适用，并以收敛和缩放保证支持。它们关注的是机器学习研究传统上注意较少的四个关键问题：一个机器学习程序怎样能分布到一个集群中去？机器学习计算怎样能通过机器间的交流连接起来？这样的交流是如何被执行的？机器间应该交流的内容是什么？通过揭示机器学习程序所独有的，而非常见于传统计算机程序中的基础性的统计和算法上的特点，并通过剖析成功案例，以揭示我们如何利用这些原则来同时设计和开发高性能的分布式机器学习软件以及通用的机器学习框架，我们为机器学习的研究人员和从业者提供了进一步塑造并扩大机器学习与系统之间的领域的机会。

关键词： 机器学习     人工智能大数据     大型模型     分布式系统     原则     理论     数据并行性     模型并行性    

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带约束的矩阵值分布式随机优化

夏子聪,刘洋,卢文联,桂卫华

《信息与电子工程前沿（英文）》 2023年 第24卷 第9期   页码 1239-1252 doi: 10.1631/FITEE.2200381

摘要： 本文研究带有不等式约束和等式约束的矩阵值分布随机优化问题。其中，问题的目标函数是具有随机变量的多个矩阵值函数的和，并以分布式方式解决了该问题。本文推导了处理约束的惩罚方法，并提出选择可行惩罚函数和惩罚增益的原则。针对随机优化问题，提出一种基于gossip模型的分布式优化算法，并对其收敛性进行证明和分析。最后，为验证所提算法的可行性，本文提供了两个数值示例。

关键词： 分布式优化     矩阵值优化     随机优化     罚函数法     Gossip模型    

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The formation mechanism and the influence factor of residual stress in machining

null

《机械工程前沿（英文）》 2014年 第9卷 第3期   页码 265-269 doi: 10.1007/s11465-014-0311-0

摘要：

Residual stresses generated in cutting process have important influences on workpiece performance. The paper presents a method of theoretical analysis in order to explicate the formation mechanism of residual stresses in cutting. An important conclusion is drawn that the accumulated plastic strain is the main factor which determines the nature and the magnitude of surface residual stresses in the workpiece. On the basis of the analytical model for residual stress, a series of simulations for residual stress prediction during cutting AISI 1045 steel are implemented in order to obtain the influences of cutting speed, depth of cut and tool edge radius on surface residual stress in the workpiece. And these influences are explained from the perspective of formation mechanism of residual stress in cutting. The conclusions have good applicability and can be used to guide the parameters selection in actual production.

关键词： residual stress     analytical model     strain     plastic     cutting parameter    

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标题 作者 时间 类型 操作

Analysis of the current situation of environmental policy of China and establishment of distributed environmental

Chaoyang FU,Wangfeng LI

期刊论文

Predictor-corrector algorithm for solving quasi-separated-flow and transient distributed-parameter model

Ping ZHANG, Guoliang DING

期刊论文

Shallow foundation response variability due to soil and model parameter uncertainty

Prishati RAYCHOWDHURY,Sumit JINDAL

期刊论文

An operating state estimation model for integrated energy systems based on distributed solution

Dengji ZHOU, Shixi MA, Dawen HUANG, Huisheng ZHANG, Shilie WENG

期刊论文

Fuzzy stochastic long-term model with consideration of uncertainties for deployment of distributed energy

Iraj AHMADIAN,Oveis ABEDINIA,Noradin GHADIMI

期刊论文

Kinematic Model Building and Servo Parameter Identification of 3-HSS Parallel Mechanism

YANG Zhi-yong, WU Jiang, HUANG Tian, NI Yan-bing

期刊论文

Shear-flexural strength mechanical model for the design and assessment of reinforced concrete beams subjectedto point or distributed loads

Antonio MARÍ,Antoni CLADERA,Jesús BAIRÁN,Eva OLLER,Carlos RIBAS

期刊论文

Probabilistic model for vessel-bridge collisions in the Three Gorges Reservoir

Bo GENG , Hong WANG , Junjie WANG ,

期刊论文

Modular architecture model of CSCD system

Hongxue XU, Hong ZHENG, Xiuying GUO

期刊论文

Performance design of a cryogenic air separation unit for variable working conditions using the lumped parametermodel

Jinghua XU, Tiantian WANG, Qianyong CHEN, Shuyou ZHANG, Jianrong TAN

期刊论文

Multi-timescale optimization scheduling of interconnected data centers based on model predictive control

期刊论文

Analysis of catchment evapotranspiration at different scales using bottom-up and top-down approaches

Xiangyu XU, Dawen YANG,

期刊论文

大数据的分布式机器学习的策略与原则

Eric P. Xing,Qirong Ho,Pengtao Xie,Dai Wei

期刊论文

带约束的矩阵值分布式随机优化

夏子聪,刘洋,卢文联,桂卫华

期刊论文

The formation mechanism and the influence factor of residual stress in machining

null

期刊论文