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A data envelopment analysis of agricultural technical efficiency of Northwest Arid Areas in China

Yubao WANG, Lijie SHI, Haojie ZHANG, Shikun SUN

《农业科学与工程前沿（英文）》 2017年 第4卷 第2期   页码 195-207 doi: 10.15302/J-FASE-2017153

摘要： Severe resource shortage and waste of resource in agricultural production make it necessary to assess efficiency to increase productivity with high efficiency and ensure sustainable agricultural development. This paper adopted an input-oriented data envelopment analysis (DEA) method with the assumption of variable returns to scale to evaluate agricultural production efficiency of 100 major irrigation districts in Northwest China in 2010. Major findings of this paper were as follows: firstly, the average value of total technical efficiency, pure technical efficiency and scale efficiency of those irrigation districts in Northwest China were 0.770, 0.825 and 0.931, respectively; secondly, 30% of irrigation districts were technically efficient, while 42% and 32% of them showed pure technical and scale efficiency respectively. Among inefficient decision-making units, total technical efficiency score varied from 0.313 to 0.966, showing significant geographical differences, but geographical differences of pure technical efficiency was more consistent with that of total technical efficiency; thirdly, input redundancy was evident. Inputs of agricultural population, irrigation area, green water, blue water, consumption of fertilizer and agricultural machinery could be reduced by 34.88%, 40.19%, 43.85%, 47.10%, 41.53% and 42.21% respectively without reducing agricultural outputs. Furthermore, irrigation area, green water and blue water had relatively high slack movement though Northwest China which is short of water resources. Based on these results, this paper drew the following conclusions: First, there is huge potential for Northwest China to improve its agricultural production efficiency, and agro-technology not input scale had greater influence on improvement. Second, farmers needed proper guidance in order to reduce agricultural inputs and it is time to centralize agricultural management for overall agricultural inputs regulation and control.

关键词： agricultural production efficiency     DEA model     input redundancy     irrigation districts     Northwest Arid Areas in China    

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Influence of kinematic redundancy on the singularity-free workspace of parallel kinematic machines

Jens KOTLARSKI, Bodo HEIMANN, Tobias ORTMAIER

《机械工程前沿（英文）》 2012年 第7卷 第2期   页码 120-134 doi: 10.1007/s11465-012-0321-8

摘要：

In this paper the effect of kinematic redundancy in order to reduce the singularity loci of the direct kinematics and to increase the operational, i.e., singularity-free, workspace is demonstrated. The proposed approach consists of additional prismatic actuators allowing one or more base joints to move linearly. As a result, a selective reconfiguration can be performed in order to avoid singular configurations. Exemplarily, kinematically redundant schemes of four structures, the 3RRR, the 3RPR, the 6UPS, and the 6RUS, are considered. The relationship between the redundancy and the operational workspace is studied and several analysis examples demonstrate the effectiveness of the proposed concept. Furthermore, the additional benefit of an increasing number of redundant actuators is discussed.

关键词： parallel robots     kinematic redundancy     singularity avoidance     operational workspace    

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Approximation of structural damping and input excitation force

Mohammad SALAVATI

《结构与土木工程前沿（英文）》 2017年 第11卷 第2期   页码 244-254 doi: 10.1007/s11709-016-0371-9

摘要： Structural dynamic characteristics are the most significant parameters that play a decisive role in structural damage assessment. The more sensitive parameter to the damage is the damping behavior of the structure. The complexity of structural damping mechanisms has made this parameter to be one of the ongoing research topics. Despite all the difficulties in the modeling of damping, there are some approaches like as linear and nonlinear models which are described as the energy dissipation throughout viscous, material or structural hysteretic and frictional damping mechanisms. In the presence of a mathematical model of the damping mechanisms, it is possible to estimate the damping ratio from the theoretical comparison of the damped and un-damped systems. On the other hand, solving the inverse problem of the input force estimation and its distribution to each SDOFs, from the measured structural responses plays an important role in structural identification process. In this paper model-based damping approximation method and a model-less structural input estimation are considered. The effectiveness of proposed methods has been carried out through analytical and numerical simulation of the lumped mass system and the results are compared with reference data. Consequently, high convergence of the comparison results illustrates the satisfactory of proposed approximation methods.

关键词： structural modal parameters     damping identification method     input excitation force identification     Inverse problem    

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Greenhouse gas emissions mitigation and economic viability of sugar crops in China

《农业科学与工程前沿（英文）》 doi: 10.15302/J-FASE-2023529

摘要：

● Sugarcane and sugar beet yield and carbon footprint rose with time but profit declined

关键词： Economic profits     GHG emissions     labor input     nitrogen input     sugar    

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Solar photovoltaic fed dual input LED lighting system with constant illumination control

Kinattingal SUNDARESWARAN,Kevin Ark KUMAR,Payyalore Raman VENKATESWARAN,Sankaran PALANI

《能源前沿（英文）》 2016年 第10卷 第4期   页码 473-478 doi: 10.1007/s11708-016-0420-z

摘要： A dual input LED lighting scheme with constant illumination is proposed in this paper. The scheme employs a photovoltaic array as the first input and a battery as the second one. A microcontroller is programmed to operate a changeover switch as well as a DC-DC converter for uninterrupted and constant illumination in work place. The scheme is suitable for conference halls, laboratories, clean rooms, marriage halls, theaters, etc. The complete modeling, design and experimentation of the proposed scheme are explained and the economic viability of the scheme is justified.

关键词： photovoltaic     LED light     dual input     P&O algorithm    

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Cutting CO emissions through demand side regulation: Implications from multi-regional input–output linear

《工程管理前沿（英文）》   页码 452-461 doi: 10.1007/s42524-022-0209-1

摘要： This study combines multi-regional input–output (MRIO) model with linear programming (LP) model to explore economic structure adjustment strategies for the reduction of carbon dioxide (CO2) emissions. A particular feature of this study is the identification of the optimal regulation sequence of final products in various regions to reduce CO2 emissions with the minimum loss in gross domestic product (GDP). By using China’s MRIO tables 2017 with 28 regions and 42 economic sectors, results show that reduction in final demand leads to simultaneous reductions in GDP and CO2 emissions. Nevertheless, certain demand side regulation strategy can be adopted to lower CO2 emissions at the smallest loss of economic growth. Several key final products, such as metallurgy, nonmetal, metal, and chemical products, should first be regulated to reduce CO2 emissions at the minimum loss in GDP. Most of these key products concentrate in the coastal developed regions in China. The proposed MRIO–LP model considers the inter-relationship among various sectors and regions, and can aid policy makers in designing effective policy for industrial structure adjustment at the regional level to achieve the national environmental and economic targets.

关键词： CO2 emissions     demand side regulation     multi-regional input–output model     linear programming model    

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Reliability analysis of the control system of large-scale vertical mixing equipment

YANG Mingjin, LI Xiwen, LI Shaoping, YANG Shuzi

《机械工程前沿（英文）》 2008年 第3卷 第2期   页码 133-138 doi: 10.1007/s11465-008-0037-y

摘要： The control system of vertical mixing equipment is a concentrate distributed monitoring system (CDMS). A reliability analysis model was built and its analysis was conducted based on reliability modeling theories such as the graph theory, Markov process, and redundancy theory. Analysis and operational results show that the control system can meet all technical requirements for high energy composite solid propellant manufacturing. The reliability performance of the control system can be considerably improved by adopting a control strategy combined with the hot spared redundancy of the primary system and the cold spared redundancy of the emergent one. The reliability performance of the control system can be also improved by adopting the redundancy strategy or improving the quality of each component and cable of the system.

关键词： composite     redundancy     monitoring     vertical     technical    

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基于拉索安全评估的普通斜拉桥和矮塔斜拉桥结构冗余度对比研究 Article

Khawaja Ali, Hiroshi Katsuchi, Hitoshi Yamada

《工程（英文）》 2021年 第7卷 第1期   页码 111-123 doi: 10.1016/j.eng.2020.07.021

摘要：

本研究基于斜拉桥和矮塔斜拉桥的拉索安全性评估，为比较斜拉桥和矮塔斜拉桥提供了新的观点。由于二者都使用拉索，人们通常认为这两种类型的桥梁具有相同的结构。但是，国际桥梁设计标准规定了二者各自的拉索安全系数。为了纠正这一误解，本研究通过考虑各种异常因素和破坏因素（如过载、钢索损耗和钢索腐蚀）的影响，对在疲劳和极限状态下的拉索的安全系数进行了比较。本研究的主要目的是解释两种类型桥梁之间的结构差异，并通过采用确定性和非确定性方法来评估其结构冗余。为了实现这一目标，根据日本现行的拉索设计指南，本文建立了两座桥的三维模型。在达到桥梁模型的平衡状态之后，以参数化方式对拉索的不同安全系数进行了静态分析。最后，采用一阶可靠性方法和蒙特卡洛方法确定了拉索的可靠性指标。分析结果表明，在相同的荷载条件下，斜拉桥和矮塔斜拉桥在不同安全系数下具有不同的结构冗余度。此外，随着拉索的安全系数的增加，其结构上的冗余大大增加。

关键词： 斜拉桥     矮塔斜拉桥     冗余     拉索     安全系数     可靠性分析    

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Estimation of regional physical imports and exports of EW-MFA in China using monetary input-output tables

Nan LI, Tianzhu ZHANG

《环境科学与工程前沿（英文）》 2013年 第7卷 第2期   页码 242-254 doi: 10.1007/s11783-012-0443-6

摘要： Given the statistical gaps in material flow among provinces in China, a method was introduced to estimate regional physical imports and exports (RPIE), which includes international and interregional imports/exports. This method uses provincial monetary input-output tables (MIOT) and international trade statistics. A coefficient matrix representing correlations between monetary value and physical mass for years 2000–2009 was obtained based on a detailed commodity classification and 22 material production sectors in MIOT. With the coefficient matrix as reference, RPIE was measured. Pilot calculation of both regional physical trade balance and domestic material consumption, as well as a brief analysis of these methods, were conducted using 2002 data.

关键词： economy-wide material flow accounts (EW-MFA)     monetary input-output table (MIOT)     regional physical imports and exports estimation    

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Oral product input to the GI tract: GIS an oral product performance technology

Gordon L. Amidon, Yasuhiro Tsume

《化学科学与工程前沿（英文）》 2017年 第11卷 第4期   页码 516-520 doi: 10.1007/s11705-017-1658-7

摘要： The patient receives a pharmaceutical product, not a drug. The pharmaceutical products are formulated with a drug, an active ingredient to produce the maximum therapeutic effect after oral absorption. Therefore, it is the product we must optimize for the patients. In order to assure the safety and efficacy of pharmaceutical products, we need an predictive tool for oral product performance in patients. Currently, we are a surprisingly long way from accomplishing that objective. If the 20th century was the ‘age of the drug’, i.e., the ‘magic bullet’, the 21st century must become the ‘age of the guided missile’, i.e., the delivery system, including the form of the active pharmaceutical ingredient (API) (‘drug’). The physical form of the drug and the delivery system must be optimized to maximize the therapeutic benefits of pharmaceutical products for humans. Oral immediate release (IR) dosage forms cannot be optimal for all drugs or likely even any drugs (APIs). Still, the formulation of pharmaceutical products has to be optimized for patients. But how do we optimize oral delivery of drugs? It is usually through ‘trial and error’, in humans! We need a better way to optimize the oral dosage forms. We have suggested to select different dissolution methodologies for this optimization based on BCS Subclasses. In this article, we present the predicted drug dissolution profile of ketoconazole as a model drug from our laboratory utilizing a gastrointestinal simulator (GIS), which is an adaptation of the ASD system. GIS consists of three chambers representing stomach, duodenum, and jejunum, to create the human gastrointestinal tract-like environment and enable the control the gastric emptying rate. This dissolution system allows the monitoring of the drug dissolution phenomena and the observation of the supersaturation and the precipitation of pharmaceutical products, which is useful information to predict dissolution of pharmaceutical products. This system can provide the actual input needed to accurately predict the input into the systemic circulation required by many of the absorption prediction packages available today.

关键词： GIS     in vivo predictive dissolution     ketoconazole     BCS subclassification     supersaturation    

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Multiple input self-organizing-map ResNet model for optimization of petroleum refinery conversion units

《化学科学与工程前沿（英文）》 2023年 第17卷 第6期   页码 759-771 doi: 10.1007/s11705-022-2269-5

摘要： This work introduces a deep-learning network, i.e., multi-input self-organizing-map ResNet (MISR), for modeling refining units comprised of two reactors and a separation train. The model is comprised of self-organizing-map and the neural network parts. The self-organizing-map part maps the input data into multiple two-dimensional planes and sends them to the neural network part. In the neural network part, residual blocks enhance the convergence and accuracy, ensuring that the structure will not be overfitted easily. Development of the MISR model of hydrocracking unit also benefits from the utilization of prior knowledge of the importance of the input variables for predicting properties of the products. The results show that the proposed MISR structure predicts more accurately the product yields and properties than the previously introduced self-organizing-map convolutional neural network model, thus leading to more accurate optimization of the hydrocracker operation. Moreover, the MISR model has smoother error convergence than the previous model. Optimal operating conditions have been determined via multi-round-particle-swarm and differential evolution algorithms. Numerical experiments show that the MISR model is suitable for modeling nonlinear conversion units which are often encountered in refining and petrochemical plants.

关键词： hydrocracking     convolutional neural networks     self-organizing map     deep learning     data-driven optimization    

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测量与信息技术

张国雄

《中国工程科学》 2000年 第2卷 第3期   页码 62-66

摘要：

测量是获取信息的重要手段。科学研究、生产、高科技发展都离不开测量。测量技术发展的重要特点是它与信息技术的融合，这是提高测量精度、在线和动态测量、复杂参数和复杂环境下测量、智能测量的需要。这一融合贯穿始终，它包括信号调制与解调、采样与重构、信号融合、数据压缩、滤波、信号变换、时间序列分析、谱分析、数据拟合与建模、模式识别、神经网络、仿真与虚拟、误差分离、误差补偿、冗余技术、决策与智能技术等，它们互相支持。文章通过三坐标测量机误差补偿、圆度和轴系误差测量，以及大型工程的柔性坐标测量系统，介绍其在提高测量精度、优化、自标定、丢失信息自恢复、系统重组等方面的作用及其关键技术。

关键词： 测量     信息技术     误差补偿     建模     冗余技术     误差分离    

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未来飞机液压系统的特点

王占林,陈斌

《中国工程科学》 1999年 第1卷 第3期   页码 5-10

摘要：

现代飞机舵面操纵系统与动力收放系统几乎都是液压驱动的。随着飞机特别是军用飞机的发展，对机载液压系统提出了更高的要求。文章对飞机特别是军用飞机液压系统的主要发展趋势进行了综述，并对国内外的飞机液压系统的研究工作进行了一定的介绍。指出：质量轻、体积小、高压化、大功率、变压力、智能化、集成化、余度技术等是未来飞机液压系统的主要发展趋势，尤其是高压变压力泵源系统对未来飞机的发展尤为重要。

关键词： 机载液压系统     高压化     变压力     余度     功率电传    

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A dynamic stiffness-based framework for harmonic input estimation and response reconstruction considering

Yixian LI; Limin SUN; Wang ZHU; Wei ZHANG

《结构与土木工程前沿（英文）》 2022年 第16卷 第4期   页码 448-460 doi: 10.1007/s11709-022-0805-5

摘要： In structural health monitoring (SHM), the measurement is point-wise but structures are continuous. Thus, input estimation has become a hot research subject with which the full-field structural response can be calculated with a finite element model (FEM). This paper proposes a framework based on the dynamic stiffness theory, to estimate harmonic input, reconstruct responses, and to localize damages from seriously deficient measurements. To begin, Fourier transform converts the dynamic equilibrium equation to an equivalent static one in the frequency domain, which is under-determined since the dimension of measurement vector is far less than the FEM-node number. The principal component analysis has been adopted to “compress” the under-determined equation, and formed an over-determined equation to estimate the unknown input. Then, inverse Fourier transform converts the estimated input in the frequency domain to the time domain. Applying this to the FEM can reconstruct the target responses. If a structure is damaged, the estimated nodal force can localize the damage. To improve the damage-detection accuracy, a multi-measurement-based indicator has been proposed. Numerical simulations have validated that the proposed framework can capably estimate input and reconstruct multi-types of full-field responses, and the damage indicator can localize minor damages even with the existence of noise.

关键词： dynamic stiffness     principal component analysis     response reconstruction     damage localization     under-determined equation    

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农业生态工程中人工辅助能产投比的计算分析研究

卞有生,柳英昆,卞晶

《中国工程科学》 2006年 第8卷 第8期   页码 28-32

摘要：

人工辅助能产投比的高低从总体上反映了农业生态系统的功能和生产效率，是系统结构功能的体现，是评价农业生态工程的重要指标。文章以河南新县10户农民为案例，具体介绍了人工辅助能产投比的计算研究方法，并报告了连续3年的研究结果。

关键词： 农业生态工程     能量产投比    

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标题 作者 时间 类型 操作

A data envelopment analysis of agricultural technical efficiency of Northwest Arid Areas in China

Yubao WANG, Lijie SHI, Haojie ZHANG, Shikun SUN

期刊论文

Influence of kinematic redundancy on the singularity-free workspace of parallel kinematic machines

Jens KOTLARSKI, Bodo HEIMANN, Tobias ORTMAIER

期刊论文

Approximation of structural damping and input excitation force

Mohammad SALAVATI

期刊论文

Greenhouse gas emissions mitigation and economic viability of sugar crops in China

期刊论文

Solar photovoltaic fed dual input LED lighting system with constant illumination control

Kinattingal SUNDARESWARAN,Kevin Ark KUMAR,Payyalore Raman VENKATESWARAN,Sankaran PALANI

期刊论文

Cutting CO emissions through demand side regulation: Implications from multi-regional input–output linear

期刊论文

Reliability analysis of the control system of large-scale vertical mixing equipment

YANG Mingjin, LI Xiwen, LI Shaoping, YANG Shuzi

期刊论文

基于拉索安全评估的普通斜拉桥和矮塔斜拉桥结构冗余度对比研究

Khawaja Ali, Hiroshi Katsuchi, Hitoshi Yamada

期刊论文

Estimation of regional physical imports and exports of EW-MFA in China using monetary input-output tables

Nan LI, Tianzhu ZHANG

期刊论文

Oral product input to the GI tract: GIS an oral product performance technology

Gordon L. Amidon, Yasuhiro Tsume

期刊论文

Multiple input self-organizing-map ResNet model for optimization of petroleum refinery conversion units

期刊论文

测量与信息技术

张国雄

期刊论文

未来飞机液压系统的特点

王占林,陈斌

期刊论文

A dynamic stiffness-based framework for harmonic input estimation and response reconstruction considering

Yixian LI; Limin SUN; Wang ZHU; Wei ZHANG

期刊论文

农业生态工程中人工辅助能产投比的计算分析研究

卞有生,柳英昆,卞晶

期刊论文