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数学模型 10

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可持续发展 2

新型电力系统 2

相变 2

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MnAl 1

Ni–Ti–Cu–V合金 1

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Functional tolerance theory in incremental growth design

YANG Bo, ZE Xiangbo, YANG Tao

《机械工程前沿（英文）》 2007年第2卷第3期页码 336-343 doi: 10.1007/s11465-007-0059-x

摘要： The evolutionary tolerance design strategy and its characteristics are studied on the basis of automation technology in the product structure design. To guarantee a successful transformation from the functional requirement to geometry constraints between parts, and finally to dimension constraints, a functional tolerance design theory in the process of product growth design is put forward. A mathematical model with a correlated sensitivity function between cost and the tolerance is created, in which the design cost, the manufacturing cost, the usage cost, and the depreciation cost of the product are regarded as control constraints of the tolerance allocation. Considering these costs, a multifactor-cost function to express quality loss of the product is applied into the model. In the mathematical model, the minimum cost is used as the objective function; a reasonable process capability index, the assembly function, and assembly quality are taken as the constraints; and depreciation cost in the objective function is expressed as the discount rate terminology in economics. Thus, allocation of the dimension tolerance as the function and cost over the whole lifetime of the product is realized. Finally, a design example is used to demonstrate the successful application of the proposed functional tolerance theory in the incremental growth design of the product.

关键词： successful transformation mathematical automation technology tolerance allocation minimum

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A new slicing method of reverse engineering based on the principle of refraction and reflection

LIU Ya-xiong, ZONG Xue-wen, TANG Yi-ping, LU Bing-heng

《机械工程前沿（英文）》 2006年第1卷第3期页码 323-328 doi: 10.1007/s11465-006-0041-z

摘要： The traditional slicing method of reverse engineering has been used in product measure from time immemorial. This method however has the disadvantage of low contrast of the cross-sectional pictures of an object. In order to overcome the said shortcoming, a new slicing method of reverse engineering, based on the principle of refraction and reflection of a prism, has been propounded. According to the reflectivity of the object, one of the illuminating methods straight illuminating or inclined illuminating is adopted. These methods can enable one to obtain the image of the cross-section of a bright object with a dark background or the opposite. Experiments have proved to show the advantages of this new slicing method for high contrast of the cross-sectional pictures. To eliminate geometrical distortions caused by the refraction and reflection of the prism, a mathematical transformation model can be set up to correct the image by using relevant software. Eventually, a RP model of a temporomandibular joint fabricated according to its slicing pictures is illustrated.

关键词： immemorial RP reflection mathematical transformation temporomandibular

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数学推理挑战人工智能

Sean O’Neill

《工程（英文）》 2019年第5卷第5期页码 817-818 doi: 10.1016/j.eng.2019.08.009

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Transformation of triclosan by a novel cold-adapted laccase from

Yuanyuan Shi, Deyang Kong, Jiayang Liu, Junhe Lu, Xiaoming Yin, Quansuo Zhou

《环境科学与工程前沿（英文）》 2017年第11卷第3期 doi: 10.1007/s11783-017-0927-5

摘要： This work investigated the transformation of triclosan (TCS) by laccase produced by a pathogen isolated from rotten tomato. The pathogen was characterized as sp. FQ, belonging to subphylum . The laccase exhibited cold-adaptation with relatively high activity at 20°C. The laccase could effectively transform TCS. Approximately 62% TCS could be removed at dose of 1.0 unit·mL in 120 min. The reaction rate appeared to be to the concentration of the substrate, suggesting the laccase activity remained stable during the reaction. Transformation products of TCS were analyzed by mass spectrometry and it was revealed that TCS dimers were formed via radical coupling pathways. During this process, laccase catalyzed oxidation of TCS to form a radical intermediate is the rate limiting step. However, this step can be reversed by humic acid. Overall, the laccase showed great potential in the treatment of phenolic contaminants. Since laccase is widely presented in natural environment, this study also revealed an important pathway involved in the transformation of phenolic contaminants in the environment.

关键词： Laccase Botrytis cinerea Triclosan Transformation Kinetics

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Prediction of cutting force in turning of UD-GFRP using mathematical model and simulated annealing

Meenu GUPTA, Surinder Kumar GILL

《机械工程前沿（英文）》 2012年第7卷第4期页码 417-426 doi: 10.1007/s11465-012-0343-2

摘要：

Glass fiber reinforced plastics (GFRPs) composite is considered to be an alternative to heavy exortic materials. According to the need for accurate machining of composites has increased enormously. During machining, the obtaining cutting force is an important aspect. The present investigation deals with the study and development of a cutting force prediction model for the machining of unidirectional glass fiber reinforced plastics (UD-GFRP) composite using regression modeling and optimization by simulated annealing. The process parameters considered include cutting speed, feed rate and depth of cut. The predicted values radial cutting force model is compared with the experimental values. The results of prediction are quite close with the experimental values. The influences of different parameters in machining of UD-GFRP composite have been analyzed.

关键词： UD-GFRP ANOVA radial cutting force PCD tool Taguchi method regression analysis simulated annealing multi objective techniques

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FOOD SYSTEMS TRANSFORMATION: CONCEPTS, MECHANISMS AND PRACTICES

《农业科学与工程前沿（英文）》 2023年第10卷第1期页码 1-3 doi: 10.15302/J-FASE-2023491

摘要： FOOD SYSTEMS TRANSFORMATION: CONCEPTS, MECHANISMS AND PRACTICES

关键词： TRANSFORMATION SYSTEMS FOOD CONCEPTS MECHANISMS

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大型农业生态工程的数学模型

卞有生,王天喜,陈正龙,崔斌

《中国工程科学》 2002年第4卷第7期页码 17-22

摘要：

文章在对胜利油田生态农场系统结构分析的基础上，根据农场规划目标，建立了由投入产出模型和线性规划模型相结合的经济发展数学模型。应用该模型指导农场的经济建设，取得了极好的效果，证明所建立的模型是正确的。

关键词：农业生态工程数学模型胜利油田

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TRANSFORMATION OF FOOD SYSTEMS: HOW CAN IT BE FINANCED?

《农业科学与工程前沿（英文）》 2023年第10卷第1期页码 109-123 doi: 10.15302/J-FASE-2023483

摘要：

● The analysis of financing for the transformation of food systems requires first a consideration of costs.

关键词： financial markets food systems development financing consumer expenditures public budgets Sustainable Development Goals

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The transformation of PAHs in the sewage sludge incineration treatment

Hui ZHANG,Le XU,Yifei ZHANG,Mengchan JIANG

《环境科学与工程前沿（英文）》 2016年第10卷第2期页码 336-340 doi: 10.1007/s11783-014-0766-6

摘要： The release of pollutants from sewage sludge in the treatment process is a worldwide tricky problem in the field of sludge treatment. In this paper, the release and reaction between monomers of polycyclic aromatic hydrocarbons (PAHs) in the sewage sludge incineration treatment were studied based on simulated experiments. The result indicates that the transformation may occurre between monomers of PAHs during their release in the treatment. Over 90% of total PAHs in sewage sludge are released at the the temperature of 300°C–750°C. The possible transformation of Naphthalene to indeno(1, 2, 3-cd)pyrene was related to the temperature of the treatment system. Here, we showed that the output rate of transformation reactions for indeno(1, 2, 3-cd)pyrene is 94% at 300°C. These findings, by identifying corresponding treatment conditions as well as techniques, can help to understand the reactions and control real outputs of PAHs in the treatment process.

关键词： release of monomers transformation of monomers PAHs sewage sludge incineration treatment

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面向数字化转型的“互联网 +”战略升级研究

何伟,张伟东,王超贤

《中国工程科学》 2020年第22卷第4期页码 10-17 doi: 10.15302/J-SSCAE-2020.04.002

摘要：

“互联网 +”行动计划推出5年来，新一代信息技术创新进一步加快，经济社会数字化转型呈现诸多新特征，这就要求深入研究构建转型新体系和探索转型新路径，谋划“互联网 +”行动举措演进升级。本文遵循技术产业变革的客观规律，基于技术经济理论范式，着重分析了当前技术、应用和政策等层面数字化转型新态势和转型前沿实践探索。研究表明，当前数字化转型技术体系和技术能力日益完善，新的转型目标蓝图逐步显现，信息技术和实体经济融合进入新阶段，面临着重构数字化转型框架体系，强化转型关键要素、突破转型关键环节的重要任务。对此建议，在“互联网 +”行动后续政策设计、国家“十四五”规划制定的过程中，发掘数字化要素潜力，推动数字化转型生态建设，构建转型创新网络，升级“互联网 +”政策保障体系，推动经济社会数字化转型迈向更高发展水平。

关键词：技术产业变革数字化转型互联网+ 产业升级

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Cooling strategies and transport theories for brain hypothermia resuscitation

LIU Jing

《能源前沿（英文）》 2007年第1卷第1期页码 32-57 doi: 10.1007/s11708-007-0004-z

摘要： The brain is one of the most important organs in a biological body whose normal function depends heavily on an uninterrupted delivery of oxygen. Unlike skeletal muscles that can survive for hours without oxygen, neuron cells in the brain are easily subjected to an irreversible damage within minutes from the onset of oxygen deficiency. With the interruption of cardiopulmonary circulation in many cardiac surgical procedures or accidental events leading to cerebral circulation arrest, an imbalance between energy production and consumption will occur which causes a rapid depletion of oxygen due to the interrupted blood-flow to the brain. Meanwhile, the cooling function of the blood flow on the hot tissue will be stopped, while metabolic heat generation in the tissues still keeps running for awhile. Under such adverse situations, the potential for cerebral protection through hypothermia has been intensively investigated in clinics by lowering brain temperature to restrain the cerebral oxygen demands. The reason can be attributed to the decreased metabolic requirements of the cold brain tissues, which allows a longer duration for the brain to endure reduced oxygen delivery. It is now clear that hypothermia would serve as the principal way for neurologic protection in a wide variety of emergency medicines, especially in cerebral damage, anoxia, circulatory arrest, respiratory occlusion, etc. However, although brain cooling has been found uniquely significant in clinical practices, the serious lack of knowledge on the mechanisms involved prevents its further advancement in brain resuscitation. Compared with the expanded trials in clinics, only very limited efforts were made to probe the engineering issues involved, which turns out to be a major obstacle for the successful operation of brain hypothermia resuscitation. From the viewpoint of biothermal medical engineering, the major theories and strategies for administering brain cooling can generally be classified into three categories: heat transfer, oxygen transport and cooling strategy. Aiming to provide a complete overview of the brain hypothermia resuscitation, this article comprehensively summarizes the recent progresses made in theoretical, practical and experimental techniques in the area. Particularly, attention is paid to the mathematical models to quantify the heat and oxygen transport inside the cerebral tissues. Typical cooling strategies to effectively lower brain temperature and thus decrease oxygen consumption rate in the cerebral tissues are analyzed. Approaches to deliver oxygen directly to the target tissues are discussed. Meanwhile, some future efforts worth pursuing within the area of brain cooling are suggested.

关键词： mathematical interruption hypothermia metabolic generation

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Crystal-to-crystal transformation from the triclinic to the cubic crystal system by partial desolvation

Qianqian Guo, Irmgard Kalf, Ulli Englert

《化学科学与工程前沿（英文）》 2018年第12卷第3期页码 433-439 doi: 10.1007/s11705-018-1743-6

摘要：

Diffusion reaction of the labile building block Mg(acacCN)₂ (acacCN= 3-cyanoacetylacetonate) with silver salts leads to a series of solvated Mg/Ag bimetallic coordination polymers with composition [Mg(acacCN)₃Ag]·solvent. Despite their common stoichiometry, the topology of these polymers depends on the solvent of crystallization. The two-dimensional coordination compound [Mg(acacCN)₃Ag]·4CHCl₃ in space group P $\overset{&OverBar;}{1}$ is obtained as platelet-shaped crystals from a mixture of methanol and chloroform. When kept in the reaction mixture, these thin plates within one week convert to isometric tetrahedral crystals of the 3D network [Mg(acacCN)₃Ag]·2CHCl₃ in the cubic space group P2₁3. The transformation reaction proceeds via dissolution and recrystallization. The co-crystallized solvent molecules play an important role for stabilizing the target structure: They subtend Cl···Cl contacts and interact via non-classical C–H···O hydrogen bonds with the coordination framework. In the new cubic coordination network, both Mg(II) and Ag(I) adopt octahedral coordination, with unprecedented face-sharing by bridging O atoms of three acetylacetonato moieties. Prolonged standing of [Mg(acacCN)₃Ag]·2CHCl₃ in the reaction medium leads to further degradation, under formation of [Ag(acacCN)].

关键词： ditopic ligand substituted acetylacetone desolvation diffraction

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and cost analysis of combined ultraviolet-biofilter systems treating gaseous chlorobenzene based on mathematical

Can WANG, Jinying XI, Hongying HU, Insun KANG

《环境科学与工程前沿（英文）》 2012年第6卷第4期页码 588-594 doi: 10.1007/s11783-012-0433-8

摘要： A conceptual mathematical model was used to evaluate the design parameters of a combined ultraviolet (UV)-biofilter system, and perform a cost analysis. Results showed that the UV light source strength and the gas residence times in the UV system (UVRT) and biofilter (EBRT) had positive effects on the overall chlorobenzene removal efficiency of the system. High ratio of UVRT to EBRT improved the removal efficiency, suggesting that the UV system has a greater effect on the overall performance of the system compared with the biofilter. Analysis of the capital and operating costs showed that the capital costs of the standalone biofilter system were much higher than those of the standalone UV system. However, the biofilter operating costs were lower than those of the UV system. The operating costs of the combined UV-biofilter system increased with increasing UVRT/EBRT ratio, whereas its capital costs decreased.

关键词： volatile organic compounds ultraviolet (UV) photodegradation biofilter modeling cost analysis

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热处理数学模型与计算机模拟

潘健生,张伟民,田东,顾剑锋,胡明娟

《中国工程科学》 2003年第5卷第5期页码 47-54

摘要：

热处理计算机模拟是热处理智能化的基础。采用三维非线性有限元模型和界面条件突变的处理方法实现了几种复杂形状零件在复杂的淬火操作过程中温度场、相变、应力和应变的模拟，模拟结果与实测结果基本相符。将气体渗碳的计算机模拟与计算机控制技术相结合，研制成功智能型密封多用炉自动生产线，已处理渗碳件3 000炉次以上，全部合格。计算机模拟技术的应用明显提高渗碳和渗氮零件的承载能力和可靠性，减少热处理变形，缩短渗碳时间。建议将机械产品的CAD、选材与热处理的CAE和产品可靠性的动力评估技术相结合，进行高可靠而又无冗余的产品设计。

关键词：热处理数学模型计算机模拟智能化

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Polymorphism and crystal transformation of penicillin sulfoxide

Dingding JING, Yongli WANG, Zhijian CHEN, Lina ZHOU, Jingkang WANG

《化学科学与工程前沿（英文）》 2011年第5卷第4期页码 442-447 doi: 10.1007/s11705-011-1140-x

摘要： Penicillin sulfoxide is the intermediate for the synthesis of 7-amino-3-desacetoxycephalosporanic acid which is one of the most important nucleuses of cephalosporin antibiotic. In this contribution, two crystal structures of penicillin sulfoxide (forms I and II) were determined by X-ray diffraction, and their thermotropic properties were investigated by differential scanning calorimetry (DSC). Furthermore, the transformation of form II to form I was studied quantitatively by Raman spectroscopy, and its rates at different temperatures were determined. The results indicate that penicillin sulfoxide is more stable as form I, and the temperature plays an important role in the crystal transformation.

关键词： penicillin sulfoxide crystallization polymorphism crystal transformation Raman spectroscopy