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Implementation aspects of a phase-field approach for brittle fracture

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Frontiers of Structural and Civil Engineering 2019年第2期13卷 417-428页

作者： G.d.HUYNH X.,ZHUANG H.NGUYEN-XUAN Institute of Continuum Mechanics Leibniz-Universitat Hannover30167 HannoverGermany Center for Interdisciplinary research in Technology Ho Chi Minh CityUniversity of Technology (HUTEH)Ho Chi Minh City Vietnam

This paper provides a comprehensive overview of a phase-field model of fracture in solid mechanics setting. We start reviewing the potential energy governing the whole process of fracture including crack initiation, branching or merging. Then, a discretization of system of equation is derived, in which the key aspect is that for the correctness of fracture phenomena, a split into tensile and compressive terms of the strain energy is performed, which allows crack to occur in tension, not in compression. For numerical analysis, standard finite element shape functions are used for both primary fields including displacements and phase field. A staggered scheme which solves the two fields of the problem separately is utilized for solution step and illustrated with a segment of Python code.

关键词： phase-field modeling FEM staggered scheme fracture

research and development of gas induced semi-solid process for industrial applications

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中国有色金属学会会刊：英文版 2010年第S3期20卷 1010-1015页

作者： J.WANNASIN S.JANUdOM T.rATTANOCHAIKUL r.CANYOOK r.BUrAPA T.CHUCHEEP S.THANABUMrUNGKUL department of Mining and Materials Engineering Faculty of EngineeringPrince of Songkla University department of Industrial Engineering Faculty of EngineeringRajamangala University of Technology Srivijaya

Several rheocasting processes are developed or applied worldwide in the metal forming *** of the new rheocasting processes is the gas induced semi-solid(GISS) *** GISS process utilizes the principle of rapid heat extraction and vigorous local extraction using the injection of fine gas bubbles through a graphite *** forming processes such as die casting,squeeze casting,gravity casting,and rheo-extrusion of the semi-solid slurries prepared by the GISS process have also been *** GISS process is capable of processing various alloys including cast aluminum alloys,die casting aluminum alloys,wrought aluminum alloys,and zinc *** GISS process is currently developed to be used commercially in the industry with the focus on forming semi-solid slurries containing low fractions solid(research and development activities of the GISS process were discussed and the status of the industrial developments of this process was reported.

关键词： gas induced semi-solid rheocasting die casting formation mechanism industrial applications

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人工智能和机器人系统——自主式地面车

系统工程与电子技术 1989年第5期11卷 71-74页

作者： r.d.Leighty 王绪武杜丽

一、引言为了在21世纪空-地-体化战斗的条件下,有效地采取军事行动,必须将新技术用于战场上。而自主式地面车是使用新技术的一种人工智能和机器人系统,这种系统对提高军队的战斗力具有潜在价值。dArPA自主式地面车的方案集中了代表新... 详细信息

一、引言为了在21世纪空-地-体化战斗的条件下,有效地采取军事行动,必须将新技术用于战场上。而自主式地面车是使用新技术的一种人工智能和机器人系统,这种系统对提高军队的战斗力具有潜在价值。dArPA自主式地面车的方案集中了代表新一代智能机器发展方向的关键技术。本文将对此方案及其进展情况和未来规划进行描述。二、dArPA的战略计算计划

关键词：自主式地面车人工智能机器人

The Potential for Genotype-by-Environment Interactions to Maintain Genetic Variation in a Model Legume–rhizobia Mutualism

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Plant Communications 2020年第6期1卷 100-111页

作者： Priya Vaidya John r.Stinchcombe department of Ecology and Evolutionary Biology University of TorontoTorontoON M5S3B2Canada Koffler Scientific reserve at Joker’s Hill University of TorontoTorontoON M5S3B2Canada

The maintenance of genetic variation in mutualism-related traits is key for understanding mutualism evolution,yet the mechanisms maintaining variation remain *** asked whether genotype-byenvironment(G3E)interaction is a potential mechanism maintaining variation in the model legume–rhizobia system,Medicago truncatula–Ensifer *** planted 50 legume genotypes in a greenhouse under ambient light and shade to reflect reduced carbon availability for *** found an expected reduction under shaded conditions for plant performance traits,such as leaf number,aboveground and belowground biomass,and a mutualism-related trait,nodule *** also found G3E for nodule number,with83%of this interaction due to shifts in genotype fitness rank order across light environments,coupled with strong positive directional selection on nodule number regardless of light *** results suggest that G3E can maintain genetic variation in a mutualism-related trait that is under consistent positive directional selection across light environments.

关键词： mutualism evolution genetic variation genotype-by-environment interaction Medicago truncatula light availability partner quality

Tool Wear Classification Using Fuzzy Logic for Machining of Al/SiC Composite Material

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Modeling and Numerical Simulation of Material Science 2012年第2期2卷 28-36页

作者： V. Kalaichelvi r. Karthikeyan d. Sivakumar V. Srinivasan department of Electronics & Instrumentation Engineering BITS-Pilani Dubai Campus Dubai International Academic City Dubai United Arab Emirates department of Electronics &Instrumentation Engineering Annamalai University Tamil Nadu India department of Manufacturing Engineering Annamalai University India department of Mechanical Engineering BITS-Pilani Dubai Campus Dubai International Academic City Dubai United Arab Emirates

Tool wear state classification has good potential to play a critical role in ensuring the dimensional accuracy of the work piece and prevention of damage to cutting tool in machining process. during machining process, tool wear is an important factor which contributes to the variation of spindle motor current, speed, feed and depth of cut. In the present work, online tool wear state detecting method with spindle motor current in turning operation for Al/SiC composite material is presented. By analyzing the effects of tool wear as well as the cutting parameters on the current signal, the models on the relationship between the current signals and the cutting parameters are established with partial design taken from experimental data and regression analysis. The fuzzy classification method is used to classify the tool wear states so as to facilitate defective tool replacement at the proper time.

关键词： Tool Wear Classification Current Signal regression Analysis Fuzzy Classification

*** Intelligent Scheme for Mitigating Black Hole Attacks in IoT

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restoring the gut microbiome for the treatment of inflammatory bowel diseases

哈尔滨工业大学学报（英文版） 2024年第3期 39页

作者： Feroz Khan A.B Weslin d dilli Babu M Mohammed Muzaffar Hussain

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World Journal of Gastroenterology 2014年第13期20卷 3468-3474页

作者： Jessica r Allegretti Matthew J Hamilton division of Gastroenterology Brigham and Women’s Hospital and Harvard Medical SchoolBostonMA 02115United States

Fecal microbiota transplantation (FMT) is considered to be a highly successful therapy for recurrent and refractory Clostridium difficile infection (CdI) based on recent clinical trials. The pathogenesis of inflammatory bowel diseases (IBd) is thought to be due in part to perturbations in the gut microflora that disrupt homeostasis. FMT restores essential components of the microflora which could reverse the inflammatory processes observed in IBd. Case reports and series for the treatment of IBd by FMT have shown promise with regards to treatment success and safety despite the limitations of the reporting. Future studies will determine the optimal delivery and preparation of stool as well as the conditions under which the recipient will derive maximal benefit. The long term consequences of FMT with regards to infection, cancer, auto-immune, and metabolic diseases are not known and will require continued regulation and study. despite these limitations, FMT may be beneficial for the treatment of ulcerative colitis and Crohn’s disease, particularly those with concurrent CdI or with pouchitis.

关键词： Crohn’ s, Ulcerative colitis, Microbiota, Fecal transplantation, dysbiosis, Pouchitis, Clostridium difficile, Probiotic

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氨对鸡体健康、生产性能的影响

中国家禽 1993年第3期15卷 37-39页

作者： d. r. Charles 邹剑敏

为了想采用光照和温度控制,在英国产蛋鸡和肉用仔鸡是饲养在十分精确控制的环境中,这意味着在舍饲和通风系统的发展中通风量的研究已很重要.因为空气交换率和室温平衡密切相关.实践上在推荐的通风率中氨常是第一限制因素. 对氨的影响早... 详细信息

为了想采用光照和温度控制,在英国产蛋鸡和肉用仔鸡是饲养在十分精确控制的环境中,这意味着在舍饲和通风系统的发展中通风量的研究已很重要.因为空气交换率和室温平衡密切相关.实践上在推荐的通风率中氨常是第一限制因素. 对氨的影响早期文献报道涉及在暴露高浓度的角膜结膜炙.1960年以后的报告出现了对生产性能的影响,以及关于易于感染呼吸道疾病,70年代中最小通风率由比较实验而得出.建议为1.5-1.6×10^(0.4)米~3/秒每公斤^(0.75)体重。某些有关减少氨按排泄率的途径已经过试验,当然鸡从组织更新中排出的内源氨必须是最小量。实际的舍饲和通风系统已在欧洲发展而成,鸡类在禽舍中干燥的可能性,使得最后的产品是干燥的、无臭味.且易于运输和处理.这种系统的一个良好例子,是高床式禽舍,气流可在板条地面下鸡粪面上经过,使其包括有上迷优点外,还有诸如良好的温度控制以及良好的饲料转化等优点.

关键词：鸡生长生产性能氨

A single-manufacturer multi-retailer sustainable reworking model for green and environmental sensitive demand under discrete ordering cost reduction

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Journal of Management Analytics 2023年第1期10卷 109-128页

作者： B.Malleeswaran r.Uthayakumar department of Mathematics The Gandhigram Rural Institute–Deemed to be UniversityGandhigramTamilnaduIndia

This paper develops an economic production quantity(EPQ)model for a singlemanufacturer multi-retailer(SMMr)production and reworking system with green and environmental sensitive customer *** minimum cost of the manufacturer has obtained under carbon emissions(CE)policies and discrete ordering cost *** model is used to optimize the total number of shipments,greening investment level,environmental measure,and lot size for productions and *** research work determines that the manufacturer’s and retailer’s profits will be increased after considering the environmental and green dependent demand of ***,the development of green and environmental demand is proposed to minimize the CE and maximize the demand for the *** the existing literature,no discrete investment is developed for reducing the cost of ordering for the retailer/***,in this paper,we have introduced *** provide numerical examples to explain the models and determine the significance of model parameters.

关键词： single manufacturer-multi retailer rework green and environmental sensitive demand discrete ordering cost reduction carbon emissions