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2020 1

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7种气态污染物 1

三维布局；势能曲面变平；布局优化；性能约束 1

启发式 1

废气净化 1

生物膜填料塔 1

菌种鉴定 1

装填问题；布局设计；卫星舱；Wang-Landau抽样算法 1

装载问题 1

遗传算法 1

重心 1

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Design of packing cup interference fit value of hypercompressors for low density polyethylene production

Da LEI,Xuehong LI,Yun LI,Xiwen REN

《能源前沿（英文）》 2019年第13卷第1期页码 107-113 doi: 10.1007/s11708-017-0450-1

摘要： The hypercompressor is one of the core facilities in low density polyethylene production, with a discharge pressure of approximately 300 MPa. A packing cup is the basic unit of cylinder packing, assembled by the interference fit between an inner cup and an outer cup. Because the shrink-fitting prestresses the packing cup, serious design is needed to gain a favorable stress state, for example, a tri-axial compressive stress state. The traditional method of designing the interference fit value for packing cups depends on the shrink-fit theory for thick-walled cylinder subject to internal and external pressure. According to the traditional method, critical points are at the inner radii of the inner and external cup. In this study, the finite element method (FEM) has been implemented to determine a more accurate stress level of packing cups. Different critical points have been found at the edge of lapped sealing surfaces between two adjacent packing cups. The maximum Von Mises equivalent stress in a packing cup increases after a decline with the rise of the interference fit value. The maximum equivalent stress initially occurs at the bore of the inner cup, then at the edge of lapped mating surfaces, and finally at the bore of the outer cup, as the interference radius increases. The traditional method neglects the influence of axial preloading on the interference mating pressure. As a result, it predicts a lower equivalent stress at the bore of the external cup. A higher interference fit value accepted by the traditional method may not be feasible as it might already make packing cups yield at the edge of mating surfaces or the bore of the external cup. Along with fatigue analysis, the feasible range of interference fit value has been modified by utilizing FEM. The modified range tends to be narrower and safer than the one derived from the traditional method, after getting rid of shrink-fit values that could result in yielding in a real packing cup.

关键词： interference fit value packing cup hypercompressor finite element method (FEM)

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HAPE3D—a new constructive algorithm for the 3D irregular packing problem

Xiao LIU,Jia-min LIU,An-xi CAO,Zhuang-le YAO

《信息与电子工程前沿（英文）》 2015年第16卷第5期页码 380-390 doi: 10.1631/FITEE.1400421

摘要： We propose a new constructive algorithm, called HAPE3D, which is a heuristic algorithm based on the principle of minimum total potential energy for the 3D irregular packing problem, involving packing a set of irregularly shaped polyhedrons into a box-shaped container with fixed width and length but unconstrained height. The objective is to allocate all the polyhedrons in the container, and thus minimize the waste or maximize profit. HAPE3D can deal with arbitrarily shaped polyhedrons, which can be rotated around each coordinate axis at different angles. The most outstanding merit is that HAPE3D does not need to calculate no-fit polyhedron (NFP), which is a huge obstacle for the 3D packing problem. HAPE3D can also be hybridized with a meta-heuristic algorithm such as simulated annealing. Two groups of computational experiments demonstrate the good performance of HAPE3D and prove that it can be hybridized quite well with a meta-heuristic algorithm to further improve the packing quality.

关键词： 3D packing problem Layout design Simulation Optimization Constructive algorithm Meta-heuristics

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A rectangle bin packing optimization approach to the signal scheduling problem in the FlexRay static

Rui ZHAO,Gui-he QIN,Jia-qiao LIU

《信息与电子工程前沿（英文）》 2016年第17卷第4期页码 375-388 doi: 10.1631/FITEE.1500232

摘要： As FlexRay communication protocol is extensively used in distributed real-time applications on vehicles, signal scheduling in FlexRay network becomes a critical issue to ensure the safe and efficient operation of time-critical applications. In this study, we propose a rectangle bin packing optimization approach to schedule communication signals with timing constraints into the FlexRay static segment at minimum bandwidth cost. The proposed approach, which is based on integer linear programming (ILP), supports both the slot assignment mechanisms provided by the latest version of the FlexRay specification, namely, the single sender slot multiplexing, and multiple sender slot multiplexing mechanisms. Extensive experiments on a synthetic and an automotive X-by-wire system case study demonstrate that the proposed approach has a well optimized performance.

关键词： FlexRay Real-time applications Rectangle bin packing Schedule optimization Slot multiplexing

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求解复杂集装箱装载问题的新方法

王涛,魏凤

《中国工程科学》 2004年第6卷第12期页码 65-68

摘要：

提出了一种求解复杂集装箱装载问题的新方法，该方法将求解复杂装箱问题分成两步：首先，根据一定的启发式规则将集装箱进行体积最大化装载，并在深度方向根据货物将空间分层；然后，用遗传算法将各层进行重心位置最优化调整，使装载方案更加符合实际运输需要。实际应用结果表明，该方法在空间利用率、重心位置以及计算效率等方面都优于其他同类方法。

关键词：装载问题启发式重心遗传算法

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Understanding the behavior of recycled aggregate concrete by using thermogravimetric analysis

Subhasis PRADHAN, Shailendra KUMAR, Sudhirkumar V. BARAI

《结构与土木工程前沿（英文）》 2020年第14卷第6期页码 1561-1572 doi: 10.1007/s11709-020-0640-5

摘要： The physio-chemical changes in concrete mixes due to different coarse aggregate (natural coarse aggregate and recycled coarse aggregate (RCA)) and mix design methods (conventional method and Particle Packing Method (PPM)) are studied using thermogravimetric analysis of the hydrated cement paste. A method is proposed to estimate the degree of hydration ( ) from chemically bound water ( ). The PPM mix designed concrete mixes exhibit lower . Recycled aggregate concrete (RAC) mixes exhibit higher and after 7 d of curing, contrary to that after 28 and 90 d. The chemically bound water at infinite time ( ) of RAC mixes are lower than the respective conventional concrete mixes. The lower , Ca(OH) bound water, free Ca(OH) content and FT-IR analysis substantiate the use of pozzolanic cement in the parent concrete of RCA. The compressive strength of concrete and cannot be correlated for concrete mixes with different aggregate type and mix design method as the present study confirms that the degree of hydration is not the only parameter which governs the macro-mechanical properties of concrete. In this regard, further study on the influence of interfacial transition zone, voids content and aggregate quality on macro-mechanical properties of concrete is needed.

关键词： recycled aggregate concrete Particle Packing Method thermogravimetric analysis chemically bound water degree of hydration Fourier transform infrared spectroscopy

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一种基于新的势能曲面变平的卫星舱布局问题的启发式方法 Article

Jing-fa LIU,Juan HUANG,Gang LI,Wen-jie LIU,Ting-zhao GUAN,Liang HAO

《信息与电子工程前沿（英文）》 2016年第17卷第10期页码 1031-1043 doi: 10.1631/FITEE.1500302

摘要：概要：卫星舱布局问题是一种带性能约束的三维布局优化问题，已经被证明具有NP难度。通过采用拟物策略和罚函数方法，我们将该问题转化为一个不带约束的优化问题。势能曲面变平法（energy landscape paving, ELP）是一个经典的基于蒙特卡洛的全局优化算法，已被成功应用于许多优化问题。ELP能够通过在复杂的势能曲面随机行走来搜索低能构形。然而，当ELP陷入又窄又深的势能曲面山谷时，它很难逃离。通过提出ELP方法中直方图函数的一种新的更新机制，我们获得了一种改进的势能曲面变平法。通过将带局部搜索的梯度法融入改进的ELP方法，为卫星舱布局问题提出了一种新的全局搜索方法nELP。本文测试了来自文献的两个有代表性的算例。计算结果显示，nELP是求解带性能约束的卫星舱布局问题的有效算法。

关键词：三维布局；势能曲面变平；布局优化；性能约束

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生物法净化几种气态污染物的研究

孙石,王洁,吴献花,李晓梅,许晓毅,邓辅唐,张唯,雷艳梅,曾二丽

《中国工程科学》 2007年第9卷第1期页码 73-77

摘要：

应用生物膜填料塔对工业废气中常见的甲苯、苯乙烯、甲醛、CS₂， SO₂ ， H₂S ， NO_x 等7种气态污染物进行净化实验，结果表明，采用专用菌种挂膜制作的生物膜填料塔对该7种气态污染物均有生物净化作用，但其对 SO₂， H₂S ， NO_x 等3种无机污染物的生物净化作用（生化去除量可达 90～ 150mg/L·h）明显优于对甲苯、苯乙烯、甲醛、二硫化碳等4种有机污染物的净化作用（生化去除量除对甲苯的可达 100 mg/L·h 外，均低于 30 mg/L·h）。研究确定了净化各污染物的适宜操作条件，并对7个专用菌种进行了鉴定。

关键词： 7种气态污染物生物膜填料塔废气净化菌种鉴定

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求解多目标卫星舱布局优化问题的带局部搜索的Wang-Landau抽样算法 Article

Jing-fa LIU,Liang HAO,Gang LI,Yu XUE,Zhao-xia LIU,Juan HUANG

《信息与电子工程前沿（英文）》 2016年第17卷第6期页码 527-542 doi: 10.1631/FITEE.1500292

摘要：卫星舱布局设计问题属于一种NP困难问题，该问题不仅仅是一种复杂的耦合系统设计问题，也是一种特殊的多目标优化问题。解决该问题最大的难点在于待优化的函数具有大量的由高能势垒分隔开的局部极小值点。Wang-Landau (WL)抽样算法是一种改进的蒙特卡罗方法，目前已成功应用于许多优化问题的求解中。本文采用WL抽样算法求解卫星舱布局优化问题。为了加快全局最优解的搜索速度，每次蒙特卡罗扫描产生新布局时便执行基于梯度法的局部搜索(LS)方法。通过结合WL抽样算法、LS方法和启发式布局更新策略，本文提出了WL-LS混合算法用于求解卫星舱最优布局。此外，为了提高算法计算效率，针对两个物体（如两矩形物体，两圆形物体或者一矩形物体和一圆形物体）之间的干涉深度，本文提出了一种快速准确的计算方法。矩形物体是正交放置的。分别测试了包含51个物体和53个物体的两个算例。在两个算例中，本文所提出的算法均超过了文献中的方法。数值结果表明，WL-LS是一种求解卫星舱布局优化问题的有效算法。

关键词：装填问题；布局设计；卫星舱；Wang-Landau抽样算法

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标题作者时间类型操作

Design of packing cup interference fit value of hypercompressors for low density polyethylene production

Da LEI,Xuehong LI,Yun LI,Xiwen REN

期刊论文

HAPE3D—a new constructive algorithm for the 3D irregular packing problem

Xiao LIU,Jia-min LIU,An-xi CAO,Zhuang-le YAO

期刊论文

A rectangle bin packing optimization approach to the signal scheduling problem in the FlexRay static

Rui ZHAO,Gui-he QIN,Jia-qiao LIU

期刊论文