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关键词

节能减排 4

减灾 2

可持续发展 2

复杂大系统 2

流形学习 2

温室气体 2

熔态还原 2

C-Bézier曲面；降阶；边界约束 1

Laplacian特征映射 1

Nd-Fe-B磨削油泥 1

Pt–Ba–Ce/γ-Al₂O₃ 催化剂，物理化学性质，NO_x存储和还原，NO_x 排放，H₂ 还原剂 1

RAMI 4.0 1

一水硬铝石 1

一维（1D） 1

三维 1

中国西部开发 1

主动控制 1

主成分 1

二氧化碳减排 1

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Robust topology optimization of multi-material lattice structures under material and load uncertainties

Yu-Chin CHAN, Kohei SHINTANI, Wei CHEN

《机械工程前沿（英文）》 2019年第14卷第2期页码 141-152 doi: 10.1007/s11465-019-0531-4

摘要： Enabled by advancements in multi-material additive manufacturing, lightweight lattice structures consisting of networks of periodic unit cells have gained popularity due to their extraordinary performance and wide array of functions. This work proposes a density-based robust topology optimization method for meso- or macro-scale multi-material lattice structures under any combination of material and load uncertainties. The method utilizes a new generalized material interpolation scheme for an arbitrary number of materials, and employs univariate dimension reduction and Gauss-type quadrature to quantify and propagate uncertainty. By formulating the objective function as a weighted sum of the mean and standard deviation of compliance, the tradeoff between optimality and robustness can be studied and controlled. Examples of a cantilever beam lattice structure under various material and load uncertainty cases exhibit the efficiency and flexibility of the approach. The accuracy of univariate dimension reduction is validated by comparing the results to the Monte Carlo approach.

关键词： robust topology optimization lattice structures multi-material material uncertainty load uncertainty univariate dimension reduction

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Optimal slot dimension for skirt support structure of coke drums

Edward WANG, Zihui XIA

《机械工程前沿（英文）》 2018年第13卷第4期页码 554-562 doi: 10.1007/s11465-018-0513-y

摘要：

The skirt-to-shell junction weld on coke drums is susceptible to fatigue failure due to severe thermal cyclic stresses. One method to decrease junction stress is to add slots near the top of the skirt, thereby reducing the local stiffness close to the weld. The most common skirt slot design is thin relative to its circumferential spacing. A new slot design, which is significantly wider, is proposed. In this study, thermal-mechanical elastoplastic 3-D finite element models of coke drums are created to analyze the effect of different skirt designs on the stress/strain field near the shell-to-skirt junction weld, as well as any other critical stress locations in the overall skirt design. The results confirm that the inclusion of the conventional slot design effectively reduces stress in the junction weld. However, it has also been found that the critical stress location migrates from the shell-to-skirt junction weld to the slot ends. A method is used to estimate the fatigue life near the critical areas of each skirt slot design. It is found that wider skirt slots provide a significant improvement on fatigue life in the weld and slot area.

关键词： coke drum stress analysis cyclic stress fatigue life skirt slots

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Immunometabolism: a new dimension in immunotherapy resistance

《医学前沿（英文）》 2023年第17卷第4期页码 585-616 doi: 10.1007/s11684-023-1012-z

摘要： Immune checkpoint inhibitors (ICIs) have demonstrated unparalleled clinical responses and revolutionized the paradigm of tumor treatment, while substantial patients remain unresponsive or develop resistance to ICIs as a single agent, which is traceable to cellular metabolic dysfunction. Although dysregulated metabolism has long been adjudged as a hallmark of tumor, it is now increasingly accepted that metabolic reprogramming is not exclusive to tumor cells but is also characteristic of immunocytes. Correspondingly, people used to pay more attention to the effect of tumor cell metabolism on immunocytes, but in practice immunocytes interact intimately with their own metabolic function in a way that has never been realized before during their activation and differentiation, which opens up a whole new frontier called immunometabolism. The metabolic intervention for tumor-infiltrating immunocytes could offer fresh opportunities to break the resistance and ameliorate existing ICI immunotherapy, whose crux might be to ascertain synergistic combinations of metabolic intervention with ICIs to reap synergic benefits and facilitate an adjusted anti-tumor immune response. Herein, we elaborate potential mechanisms underlying immunotherapy resistance from a novel dimension of metabolic reprogramming in diverse tumor-infiltrating immunocytes, and related metabolic intervention in the hope of offering a reference for targeting metabolic vulnerabilities to circumvent immunotherapeutic resistance.

关键词： immune cell immunometabolism metabolic reprogramming immunotherapy resistance tumor microenvironment immune checkpoint inhibitor

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基于非线性数据变换的离群点检测算法

徐雪松,张谞,宋东明,张宏,刘凤玉

《中国工程科学》 2008年第10卷第9期页码 74-78

摘要：

为了提高高维数据集合离群数据挖掘效率，在分析了传统的离群数据挖掘算法优点和缺点的基础上，提出了一种离群点检测算法，首先将非线性问题转化为高维特征空间中的线性问题，然后利用非线性数据变换进行维数约减，对所得数据对象每个投影分量逐个判断数据点是否是离群点，通过实验证明该算法不仅可用于线性可分数据集的离群点检测，而且可用于线性不可分数据集的离群点检测，表明了算法的优越性。

关键词：维数消减核函数主成分离群数据

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Diagnosis method based on wavelet coefficient scale relativity correlation dimension for fault

GU Junjie, TIAN Jin, PENG Xuezhi

《能源前沿（英文）》 2008年第2卷第2期页码 164-168 doi: 10.1007/s11708-008-0031-4

摘要： Correlation dimension as a tool to describe machinery condition is introduced. Vibration signals of the fan under different working conditions are analyzed using a threshold filtering algorithm based on the region relativity of the wavelet coefficients for reducing noise. The result shows that the characteristics of the signal could be preserved completely. The correlation dimension is able to identify conditions of the fan with faults compared with the normal condition, thereby providing an effective technology for condition monitoring and fault diagnosis of mechanical equipment.

关键词： effective technology monitoring mechanical equipment relativity Correlation

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Structural dimension optimization and mechanical response analysis of fabricated honeycomb plastic pavement

Zixuan CHEN; Tao LIU; Xiao MA; Hanyu TANG; Jianyou HUANG; Jianzhong PEI

《结构与土木工程前沿（英文）》 2022年第16卷第7期页码 896-908 doi: 10.1007/s11709-022-0856-7

摘要： Because of favorable mechanical properties, deformation resistance and being conducive to environmental protection, honeycomb fabricated plastic pavement slabs are highly recommended these years. At present, most studies focus on the performance of plastic materials, however, the dimension optimization of fabricated plastic pavement slab is rarely mentioned. In this paper, an optimized geometry of the honeycomb pavement slab was determined through finite element analysis. Mechanical response of honeycomb slabs with different internal dimensions and external dimensions were explored. Several dimension factors were taken into consideration including the side length, rib thickness, the thickness of both top and bottom slabs of honeycomb structure and the length, the width and the thickness of the fabricated plastic slab. The results showed that honeycomb pavement slab with 6 cm bottom slab, 12 cm top slab,18 cm side length and 6 cm rib thickness is recommended, additionally, an external dimension of 4 m × 4 m × 0.45 m is suggested. Then, the mechanical responses of this optimized fabricated plastic slab were further investigated. Significance of different influencing factors, including wheel load, elastic modulus of plastic material, base layer thickness, soil foundation modulus and base layer modulus were ranked.

关键词： honeycomb structure plastic pavement dimension optimization mechanical response factor significance

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数据中心设计——一种微结构材料体系设计新方法 Article

Wei Chen, Akshay Iyer, Ramin Bostanabad

《工程（英文）》 2022年第10卷第3期页码 89-98 doi: 10.1016/j.eng.2021.05.022

摘要：

在高通量计算材料科学时代，材料基因组计划的核心是为计算材料设计建立数据处理、材料结构和材料属性（PSP）之间的关系。近年来，在数据获取和存储，微结构表征和重建（MCR），机器学习（ML），材料建模和仿真，数据处理、材料制造和实验方面取得的技术进步，显著提升了研究人员在PSP关系的建立和逆向材料设计方面的能力。本文将从设计研究的角度审视这些进步。特别介绍了一种数据中心设计方法，并从本质上将该方法分为三个方面：设计表征、设计评估和设计合成。每个方面的发展都由领域知识指导并从中受益。因此，针对每个方面，提出了一种应用广泛的计算方法，这些方法的集成实现了以数据为中心的材料发现和设计。

关键词：材料信息学机器学习微结构重建贝叶斯优化混合变量模型降维材料设计

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PD pattern recognition based on multi-fractal dimension in GIS

ZHANG Xiaoxing, YAO Yao, TANG Ju, ZHOU Qian, XU Zhongrong

《机械工程前沿（英文）》 2008年第3卷第3期页码 270-275 doi: 10.1007/s11465-008-0042-1

摘要： This paper designs four types of gas insulated substation (GIS) defect models based on partial discharge (PD) characteristics and its defections. The GIS gray intensity images are constructed based on the mass specimens gathered by the ultra-high frequency and high-speed sampling systems. The multi-fractal dimension is founded on the box-counting dimension and multi-fractal theories. The GIS gray intensity images distillation methods, based on multi-fractal characteristics, is put forward. The box-counting dimension, multi-fractal dimension, and discharge centrobaric characteristics of the PD images are also extracted. The characteristic variables are then classified by the radial basis function (RBF) network. Identified results show that the methods can effectively elevate the discrimination of the four types of defects in GIS.

关键词： substation high-speed discharge centrobaric network ultra-high frequency

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基于RAMI 4.0解读新一代智能制造

赵敏

《中国工程科学》 2018年第20卷第4期页码 90-96 doi: 10.15302/J-SSCAE-2018.04.015

摘要：

为了深入认识中国工程院“基于新一代人工智能的‘中国智能制造发展战略研究报告’”的重要意义，笔者采取了解构和重构的方法，对德国工业4.0参考架构模型（RAMI 4.0）进行了剖析，并与中国工程院报告中提出的智能制造总体架构做了对比，发现了彼此的相同和差异之处，认为中国版智能制造总体架构在智能程度上更胜一筹，这是中国人对智能制造发展的贡献。同时该分析过程亦加深了对二者的认识。

关键词： RAMI 4.0 信息物理系统（CPS）基本范式新一代人工智能架构技术维组织维价值维

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Temporal dimension and water quality control in an emission trading scheme based on water environmental

Zhaoxing HAN, Zhenyao SHEN, Yongwei GONG, Qian HONG

《环境科学与工程前沿（英文）》 2011年第5卷第1期页码 119-129 doi: 10.1007/s11783-011-0272-z

摘要： Emission trading is one of the most effective alternatives to controlling water pollution. Water environmental functional zone (WEFZ) is used to determine the water quality standard and identify the zone boundary for each river or reach. In this study, a new emission trading scheme was addressed based on WEFZ, accounting for both the temporal dimension and water quality control. A temporal factor of emission trading was proposed based on variations in the environmental capacity within a year by dividing the year into three periods, including high, normal, and low periods of environmental capacity. During each period, emission trading was implemented exclusively. A water quality-control scheme was suggested based on the water quality requirement in the water functional zone, in which the water quality at the downstream boundary of the zone was required to meet the water standard following auto-purification in the stream. Two methods of calculating water quality control are addressed for point-source pollution and non-point-source pollution. The calculated temporal dimension and water quality control were located in Dongxi River of the Daning Watershed in the Three Gorges Watershed. The high period was during June, July, and August, the normal period was during April, May, September, and October, and the low period was during January, February, March, November, and December. The results from the water quality calculation demonstrated that the discharge of point-source and non-point-source pollutions led to an excess of common contaminants at the downstream boundary of WEFZ. The temporal and spatial factors above should be incorporated into the emission trading scheme based on WEFZ.

关键词： emission trading water functional zone water quality control

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Design and analysis of a class of redundant collaborative manipulators with 2-dimension large rotational

Xiaodong JIN, Yuefa FANG, Dan ZHANG, Xueling LUO

《机械工程前沿（英文）》 2020年第15卷第1期页码 66-80 doi: 10.1007/s11465-019-0570-x

摘要： The parallel spindle heads with high rotational capability are demanded in the area of multi-axis machine tools and 3D printers. This paper focuses on designing a class of 2R1T (R: Rotation; T: Translation) parallel spindle heads and the corresponding collaborative 5-axis manipulators with 2-dimension (2D) large rotational angles. In order to construct 2D rotational degrees of freedom (DOF), a platform with 2-dimension revolute joints is proposed first. Based on the constraint screw theory, the feasible limbs that can be connected in the platform are synthesized. In order to provide constant rotational axis for the platform, a class of redundant limbs are designed. A class of redundant 2R1T parallel spindle heads is obtained by connecting the redundant limbs with the platform and the redundant characteristics are verified by the modified Grübler-Kutzbach criterion. The corresponding 5-axis collaborative manipulators are presented by constructing a 2-DOF series translational bottom moving platform. The inverse kinematics and the orientation workspace as well as the decoupling characteristics of this type of 2R1T parallel spindle heads are analyzed. The results show that these manipulators have large 2D rotational angles than the traditional A3/Z3 heads and can be potentially used in the application of multi-axis machine tools and the 3D printers.

关键词： parallel mechanism redundant mechanism large rotational angles machine tools 2R1T spindle head collaborative manipulator

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A solution to stochastic unit commitment problem for a wind-thermal system coordination

B. SARAVANAN,Shreya MISHRA,Debrupa NAG

《能源前沿（英文）》 2014年第8卷第2期页码 192-200 doi: 10.1007/s11708-014-0306-x

摘要： Unit commitment (UC) problem is one of the most important decision making problems in power system. In this paper the UC problem is solved by considering it as a real time problem by adding stochasticity in the generation side because of wind-thermal co-ordination system as well as stochasticity in the load side by incorporating the randomness of the load. The most important issue that needs to be addressed is the achievement of an economic unit commitment solution after solving UC as a real time problem. This paper proposes a hybrid approach to solve the stochastic unit commitment problem considering the volatile nature of wind and formulating the UC problem as a chance constrained problem in which the load is met with high probability over the entire time period.

关键词： unit commitment (UC) randomness wind generation univariate chance constrained

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舰船修理文件编制六维度管理方法研究

陈志敏,阳斌

《中国工程科学》 2015年第17卷第5期页码 83-89

摘要：

针对舰船基地级修理文件编制规律与技术特点，提出了成系统、科学的基地级修理文件编制六维度管理方法。在分析舰船装备基地级修理文件国外编制现状的基础上，针对修理文件编制难度大、内容多、涉及外协单位多、质量和进度管理难度大的特点，梳理出基地级修理文件体系，提出了从要求、样例、维修分析、知识库、质量管理、进度管理六个维度对修理文件编制的质量和进度进行管理的创新方法，从工程可操作性上对修理文件的编制管理方法进行了阐述，其研究成果对落实舰船装备基地级修理文件编制工作具有重要意义。

关键词：舰船；修理文件；六维度管理方法；维修分析

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Inverse Kinematics Analysis of General 6R Serial Robot Mechanism Based on Groebner Base

WANG Yan, HANG Lu-bin, YANG Ting-li

《机械工程前沿（英文）》 2006年第1卷第1期页码 115-124 doi: 10.1007/s11465-005-0022-7

摘要：

This study presents a solution for the inverse kinematics problem in serial 6R manipulator. Using only seven equations composed of Duffy s four kinematical equations containing three angles and three corresponding angles identical equations instead of the traditional 14 equations, the authors reduced the inverse kinematics problem in the general 6R manipulator to a univariate polynomial with a minimum degree based on the Groebner Base method. From that, they concluded that the maximum number of the solutions is 16, generally. Also, the mathematics mechanization method can be extended to solve other mechanism problems involving nonlinear equations symbolically.

关键词： identical manipulator univariate polynomial mechanism traditional