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A facile method to fabricate surfaces showing superhydrophilicity in air and superhydrophobicity in oil

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Science China(Technological Sciences) 2017年第11期60卷 1724-1731页

作者： YE XiangDong GUO YuXuan JIA YanChao YE Xin WANG Shuai CAI AnJiang WU XiaoJun SHAO JinYou Shaanxi Key Laboratory of Nanomaterials and Nanotechnology Xi'an University of Architecture and Technology State Key Laboratory of manufacturing systems engineering Xi'an Jiaotong University

The changes of the wettability of the solid surfaces have attracted massive attention due to their important practical implications in numerous fields. As a new subject, the research on the wettability under the different environments is still in its early stage. So the fundamental research must be performed for the practical applications under different environments. However, it is seldom that the comprehensive wettability of a surface in air, in water and in oil has been reported. In this paper, the authors investigated the wettability of the stainless steel mesh coated with polyurethane in the above three different environments. The surface of the uncoated mesh was found to be hydrophobic in air, but the surface of the coated mesh was superhydrophilic in air. More interestingly, the surfaces of the coated meshes were superoleophilic in water and superhydrophobic in oil. Due to the coated meshes with these wettabilities were fabricated via a facile two-step method, the presented method may be adopted for large-scale industrial production, in various fields, such as icing prevention or the oil-field industry.

关键词： wettability polyurethane coated mesh superhydrophilicity superhydrophobicity superoleophilicity

Obsolescence optimization of electronic and mechatronic components by considering dependability and energy consumption

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Journal of Central South University 2013年第5期20卷 1221-1225页

作者： M.A.Mellal S.Adjerid D.Benazzouz S.Berrazouane E.J.Williams Solid Mechanics and System Laboratory Faculty of Engineering Sciences (FSI)M'Hamed Bougara University Faculty of engineering Sciences (FSI) M'Hamed Bougara University Decision Sciences College of BusinessUniversity of Michigan industrial and manufacturing systems engineering Department College of Engineering and Computer ScienceUniversity of Michigan

Nowadays, rapid technological progress influences the dependability of equipments and also causes rapid obsolescence. The mechatronic and electronic equipment components are mostly affected by obsolescence. A new challenger unit possesses identical functionalities, but with higher performances. This work aims to find the optimal number of components which should be replaced by new-type units, under budgetary constraints. In this work, the new challenger unit is characterized by lower energy consumption and the optimization steps are based on genetic algorithm (GA). The result shows the importance of this type of replacement in order to economize energy consumption and to deal with obsolescence.

关键词： obsolescence lower energy consumption mechatronic and electronic components genetic algorithm

Design and experiment of bionic stubble breaking-deep loosening combined tillage machine

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International Journal of Agricultural and Biological engineering 2021年第4期14卷 123-134,I0002页

作者： Jiale Zhao Yun Lu Mingzhuo Guo Jun Fu Yijia Wang College of Biological and Agricultural engineering Jilin UniversityChangchun 130025China Key Laboratory of Bionics engineering Ministry of EducationJilin UniversityChangchun 130025China Department of industrial and manufacturing systems engineering The University of Hong KongPokfulam RoadHong KongChina

Under the conditions of straw returning operation,there are three major technical bottlenecks in the Phaeozem region of northeast China,namely low stubble breaking rate,poor tillage depth consistency,and high fuel *** this research,a bionic stubble-deep loosening combined tillage machine(BSD)was designed through bionic prototype analysis,coupled bionic analysis,coupled bionic design,theoretical analysis and application of intelligent control *** consists of a bionic stubble breaking device and a bionic self-excited vibratory deep loosening *** on the unique biting pattern of locust mouthparts on maize rootstocks,the bionic stubble breaking device adopted a new multi-segment serrated bionic structure and a symmetrical rotational motion,which could significantly increase the stubble breaking rate(pdepth control system with a fuzzy algorithm,which significantly improved the tilling depth consistency(pdepth coefficient of variation by 12.73%and 13.48%,and reduced the specific fuel consumption by 36 g/km·h and 40 g/km·h compared to the two most common *** operating performance of the three kinds of machines will decrease with the increase of operating speed,and the BSD has the least decrease.

关键词： bionics stubble breaking deep loosening combined tillage machine

Comparison of the effects of submerged laser peening,cavitation peening and shot peening on the improvement of the fatigue strength of magnesium alloy AZ31

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Journal of Magnesium and Alloys 2023年第5期11卷 1592-1607页

作者： Hitoshi Soyama Chieko Kuji Yiliang Liao Department of Finemechanics Tohoku University6-6-01 AobaAramakiAoba-kuSendai 980-8579Japan Department of industrial and manufacturing systems engineering Iowa State University2529 Union Dr.AmesIA 50011United States of America

To investigate the improvement in the fatigue strength of magnesium alloy by peening methods,magnesium alloy AZ31 was treated by submerged laser peening(SLP),cavitation peening(CP),and shot peening(SP),and the fatigue properties were evaluated by a plane bending fatigue *** the case of SLP,both the impact induced by laser ablation(LA)and that caused by laser cavitation(LC),which developed after LA,were *** the present study,the fatigue life at a constant bending stress was examined to determine the suitable *** was found that the fatigue strengths at N=10^(7)for the SLP,CP,and SP specimens treated by each optimum condition were 56%,18%,and 16%higher,respectively,than that of the non-peened(NP)specimen,which was 97 *** key factors in the improvement of fatigue strength by peening methods were work hardening and the introduction of compressive residual stress.

关键词： Magnesium alloy Fatigue strength Laser peening Cavitation peening Shot peening

Evaluation of Process and Economic Feasibility of Implementing a Topping Cycle Cogeneration

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Energy engineering 2023年第2期120卷 345-365页

作者： Unique Karki Bhaskaran Gopalakrishnan Department of industrial&Management systems engineering West Virginia UniversityMorgantown26506USA

industrial applications that require steam for their end-use generally utilize steam boilers that are typically oversized,citing operations ***,gas turbine-based power plants corroborate a gas turbine system that may eventually relieve the usable exhaust into the *** study explores the economic and technical feasibility of a topping cycle combined heat and power(CHP)*** does so by leveraging a partially loaded boiler or gas turbine by increasing its unused load to generate steam and heat for subsequent *** this end,a decision support tool(COGENTEC)was developed,which emulates a given facility’s boiler or gas-turbine system,and its operational parameters with the application of steam *** tool provides necessary insights into the most appropriate parameters that enable a CHP system to be technically and economically *** on input variables such as boiler-rated capacity,steam pressure,steam temperature,and existing boiler load,among others,COGENTEC designs a topping cycle CHP system to inform a user whether this system is feasible in their facility or *** applicable,the tool assists the user to realize the point of break-even(fuel cost incurred and cost savings)at the desired steam flow *** also conducts sensitivity analyses between energy usage,cost savings,and payback on the investment of the operating parameters to understand the relationship between relevant *** utilizing parameters from a pulp and paper manufacturing facility,the research determines that the fuel cost,electricity cost,and steam flow rate are the most important parameters for the feasibility of the system with a desirable payback on the investment.

关键词： Cogeneration topping cycle CHP industrial decarbonization energy efficiency

Effect of Prior Austenite Grain Size on the Morphology and Mechanical Properties of Martensite in Medium Carbon Steel

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Journal of Materials Science & Technology 2012年第5期28卷 461-466页

作者： Y.Prawoto N.Jasmawati K.Sumeru Faculty of Mechanical engineering Universiti Teknologi Malaysia81310 UTMSkudaiJohor 81310Malaysia dept.of Refrigeration and Air Conditioning engineering Politeknik Negeri BandungIndonesia

In industrial application,unintentional manufacturing line troubles often consequence in heating raw materials excessively,in terms of either time or *** of the effects of such occurrence is a product with a variation of prior austenite grain size,even if after the heat treatment the end result is the same,*** variation of the prior austenite grain size is believed to vary the end results of the *** undesirable variation includes the variation of fatigue resistance,impact strength,yield strength,hardness,*** research studies the effect of the prior austenite grain size on the morphology of the martensite *** results show that within the typical industrial application of temperature and holding time set up,as holding time or the temperature increases,the prior austenite average diameter *** block and packet sizes in the martensite also *** variation of mechanical property dependence on the grain size is indeed due to the different characteristics reflected in the martensite *** respect to the same area,smaller grain has more blocks and packets,which agrees with higher dislocation density verified with transmission electron microscopic evaluation.

关键词： Heat treating Mechanical testing Carbon/alloy steels

Dynamic Performance Prediction in Batch-Based Assembly System with Bernoulli Machines and Changeovers

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Complex System Modeling and Simulation 2022年第3期2卷 224-237页

作者： Zunjun Wang Zhiyang Jia Xiuxuan Tian Jingchuan Chen Bei Pan State Key Laboratory of Intelligent Control and Decision of Complex systems School of AutomationBeijing Institute of TechnologyBeijing 100081China Department of industrial and manufacturing systems engineering University of Hong KongHong Kong 999077China School of engineering Tokyo University of TechnologyTokyo 192-0982Japan

Worldwide competition and diverse demand of customers pose great challenges to manufacturing enterprises. How to organize production to achieve high productivity and low cost becomes their primary task. In the mean time, the rapid pace of technology innovation has contributed to the development of new types of flexible automation. Hence, increasing manufacturing enterprises convert to multi-product and small-batch production, a manufacturing strategy that brings increased output, reduced costs, and quick response to the market. A distinctive feature of small-batch production is that the system operates mainly in the transient states. Transient states may have a significant impact on manufacturing systems. It is therefore necessary to estimate the dynamic performance of systems. As the assembly system is a typical class of production systems, in this paper, we focus on the problem of dynamic performance prediction of the assembly systems that produce small batches of different types of products. And the system is assumed to be characterized with Bernoulli reliability machines, finite buffers, and changeovers. A mathematical model based on Markovian analysis is first derived and then, the analytical formulas for performance evaluation of three-machine assembly systems are given. Moreover, a novel approach based on decomposition and aggregation is proposed to predict dynamic performance of large-scale assembly systems that consist of multiple component lines and additional processing machines located downstream of the assemble machine. The proposed approach is validated to be highly accurate and computationally efficient when compared to Monte Carlo simulation.

关键词： flexible assembly system dynamic performance Bernoulli machines finite buffers changeovers

A large-area bionic skin for high-temperature energy harvesting applications

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Nano Research 2023年第7期16卷 10245-10255页

作者： Zhaojun Liu Bian Tian Yao Li Jiaming Lei Zhongkai Zhang Jiangjiang Liu Qijing Lin Chengkuo Lee Zhuangde Jiang State Key Laboratory for Mechanical manufacturing systems engineering School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an 710049China Department of Electrical&Computer engineering National University of SingaporeSingapore 117576Singapore Shandong Laboratory of Yantai Advanced Materials and Green manufacturing Yantai 265503China

For the large amount of waste heat wasted in daily life and industrial production,we propose a new type of flexible thermoelectric generators(F-TEGs)which can be used as a large area bionic skin to achieve energy harvesting of thermal *** reference to biological structures such as pinecone,succulent,and feathers,we have designed and fabricated a biomimetic flexible TEG that can be applied in a wide temperature range which has the highest temperature energy harvesting capability *** laminated free structure of the bionic F-TEG dramatically increases the efficiency and density of energy *** F-TEGs(single TEG only 101.2 mg in weight),without an additional heat sink,demonstrates the highest output voltage density of 286.1 mV/cm^(2)and the maximum power density is 66.5 mW/m^(2) at a temperature difference of nearly 1000℃.The flexible characteristics of F-TEGs make it possible to collect the diffused thermal energy by flexible attachment to the outer walls of high-temperature pipes and vessels of different diameters and *** work shows a new design and application concept for flexible thermal energy collectors,which fills the gap of flexible energy harvesting in high-temperature environment.

关键词： bionic structure high-temperature flexible thermoelectric generators(TEGs)

Jerk-limited feedrate scheduling and optimization for five-axis machining using new piecewise linear programming approach

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Science China(Technological Sciences) 2019年第7期62卷 1067-1081页

作者： SUN YuWen CHEN ManSen JIA JinJie LEE Yuan-Shin GUO DongMing School of Mechanical engineering Dalian University of Technology Dalian 116024 China Department of industrial and systems engineering North Carolina State University Raleigh NC 27695 USA

In this paper, a new computation method and an optimization algorithm are presented for feedrate scheduling of five-axis machining in compliance with both machine drive limits and process limits. Five-axis machine tool with its ability of controlling tool orientation to follow the sculptured surface contour has been widely used in modern manufacturing industry. Feedrate scheduling serving as a kernel of CNC control system plays a critical role to ensure the required machining accuracy and reliability for five-axis machining. Due to the nonlinear coupling effects of all involved drive axes and the saturation limit of servo motors, the feedrate scheduling for multi-axis machining has long been recognized and remains as a critical challenge for achieving five-axis machine tools’ full capacity and advantage. To solve the nonlinearity nature of the five-axis feedrate scheduling problems, a relaxation mathematical process is presented for relaxing both the drive motors’ physical limitations and the kinematic constraints of five-axis tool motions. Based on the primary optimization variable of feedrate, the presented method analytically linearizes the machining-related constraints, in terms of the machines’ axis velocities, axis accelerations and axis jerks. The nonlinear multi-constrained feedrate scheduling problem is transformed into a manageable linear programming problem. An optimization algorithm is presented to find the optimal feedrate scheduling solution for the five-axis machining problems. Both computer implementation and laboratorial experiment testing by actual machine cutting were conducted and presented in this paper. The experiment results demonstrate that the proposed method can effectively generate efficient feedrate scheduling for five-axis machining with constraints of the machine tool physical constraints and limits. Compared with other existing numerical methods, the proposed method is able to find an accurate analytical solution for the nonlinear cons

关键词： five-axis machining feedrate scheduling jerk linear programming optimization