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基于熵函数的流水车间小批生产信息量测度

自动化学报 2020年第10期46卷 2221-2228页

作者：张志峰 janet david 南昌航空大学经济管理学院南昌330063 内蒙古科技大学经济管理学院包头014010 牛津大学工程科学系牛津 OX13PJ英国

流水车间生产中,批量及批次的信息量测度意味着对描述不同批量及批次在工作站的状态所需信息量的度量,即求解批量及批次的信息熵表达.现有批量及批次信息控制研究主要集中在批量调度问题上,鲜有针对生产中的批量及批次与管理生产所需信... 详细信息

流水车间生产中,批量及批次的信息量测度意味着对描述不同批量及批次在工作站的状态所需信息量的度量,即求解批量及批次的信息熵表达.现有批量及批次信息控制研究主要集中在批量调度问题上,鲜有针对生产中的批量及批次与管理生产所需信息量关系的研究,造成研究结论很难为决策者从信息管理角度选择生产方式提供理论依据.针对上述问题,在分析信息熵度量特性基础上,理论上首次建立流水车间生产线不同批次相同加工时间条件下的批量及批次的信息熵函数,作为度量生产系统状态所需信息量的基础,并由此提出生产批次与熵函数变化关系两个定理,即:生产批次的信息熵函数单调递减;批次趋于无穷大时,系统信息熵趋于零.采用求导法与极值法分别对所提定理给予充分证明,从而理论上证明了流水车间的加工批次增加(或批量减小),则系统的信息熵降低.分别取工作站数量为10和20进行实证研究,以图示表达的结果再次验证了所提定理的正确性.批量与批次的信息量测度理论研究,对实际流水车间生产批量与批次的作业安排及最终生产方式的选择,都具有重要的理论支撑和现实指导意义.

关键词：熵函数小批生产流水车间信息量

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流水车间加工信息测度与控制

中国科学：技术科学 2024年第6期54卷 1091-1104页

作者：张志峰 janet david 刘俊桂林航天工业学院管理学院桂林541004 Department of Engineering Science University of OxfordOxford OX13PJUK 华中科技大学机械科学与工程学院武汉430074

流水车间加工信息的有效测度是实施加工批量决策的前提.当前多品种小批量生产信息控制研究多以生产技术、范式及智能算法等理论优化工作为主,极少开展生产的加工批量与其状态控制所需信息之间关系的研究,导致研究结论过于理论化而难以... 详细信息

流水车间加工信息的有效测度是实施加工批量决策的前提.当前多品种小批量生产信息控制研究多以生产技术、范式及智能算法等理论优化工作为主,极少开展生产的加工批量与其状态控制所需信息之间关系的研究,导致研究结论过于理论化而难以应用于现实生产.针对此研究局限性,本文从信息论角度出发,根据制造马尔科夫过程,定义流水车间的加工批量信息熵并解析其度量特性.进一步,构建流水车间加工批量信息熵函数,理论上证明其函数单调递减性.通过建立流水车间加工批次信息测度模型,确定生产线批次加工信息的组成结构,实现对工件加工所需信息量的测度.实证研究中,将平均调整准备时间、平均加工时间及完工时间等观测数据应用于实际企业的减速器生产线,做出不同参量与加工批量变化关系图,确定相关参数条件下生产线的最优加工批量.根据研究结果,提出有效减少管理与控制生产线所需信息量的对策,在验证所建熵模型科学性与有效性的同时,也为实际生产中的批量决策提供准确的现实指导.

关键词：流水车间加工批量熵函数信息测度

Materials and technology of Chinese jades dating to the Western Zhou period (1050―771 BCE)

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Science China(Technological Sciences) 2008年第4期51卷 467-480页

作者： janet G DOUGLAS Department of Conservation and Scientific Research Freer Gallery of Art / Arthur M. Sackler Gallery Smithsonian Institution

Excavated jades dating to the Western Zhou period (1050―771 BCE) from the Xi’an area in Shaanxi Province, China, and contemporaneous jades in the collections of the Arthur M. Sackler Gallery at the Smithsonian Institution have been studied to learn about the jade and stone materials and how they were worked during the Western Zhou period. Materials identification was carried out using a combination of techniques such as Fourier-transform infrared spectroscopy and X-ray diffraction. Tool marks were studied using stereomicroscopy and examination of mold impressions using scanning electron microscopy. All of these objects were pro- duced through simple processes involving solid drilling, riffling, and sharp point abrasion; and no evidence was found for the use of rotary tools for incising or sawing.

关键词： jade nephrite stone China Western Zhou scanning electron microscopy materials technology tool marks

Sexual selection and hermaphroditic organisms： Testing theory

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Current Zoology 2013年第4期59卷 579-588页

作者： janet L. LEONARD Joseph M. Long Marine Laboratory University of California-Santa Cruz Santa Cruz CA 94019 USA

Sexual selection is widespread if not ubiquitous in hermaphroditic organisms. Although many phenomena that have been described as sexual selection in gonochores, （e.g. harem polygamy, multiple mating, elaborate courtship, even secondary sexual characters） can be found in some hermaphrodites, what is more interesting is the ways in which sexual selection in her- maphrodites may differ from dioecious taxa. In hermaphrodites, an individual＇s mating success includes its success from both sexual roles. Secondly, in many simultaneously hermaphroditic taxa there is strong evidence of sexual selection and yet the ope- rational sex ratio is 1：1, by definition. Many simultaneous hermaphrodites have elaborate courtship and genital anatomy, suggest- ing sexual selection plays an important role in reproductive success. Sperm competition and cryptic female choice mean that the number of mates acquired is not necessarily a predictor of reproductive success. Even in simultaneous hermaphrodites with re- ciprocal mating, variance in reproductive success through the male role and through the female role may differ in a population. Moreover hermaphrodites may choose to emphasize one sexual role over the other. Data suggest that the preferred role varies in hermaphrodites, which creates an opportunity to test fundamental predictions and assumptions of sexual selection theory. Hermaphrodites may vary their emphasis on one sexual role over the other either developmentally or behaviorally in response to environmental or social parameters. How they use this capability in acquiring more or higher quality mates still requires study

关键词： Sexual selection Hermaphrodites Mate choice Reproductive success

Parameter-Free Search of Time-Series Discord

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Journal of Computer Science & Technology 2013年第2期28卷 300-310页

作者： Wei Luo Marcus Gallagher janet Wiles School of Information Technology Deakin University School of Information Technology and Electrical Engineering University of Queensland

Time-series discord is widely used in data mining applications to characterize anomalous subsequences in time series. Compared to some other discord search algorithms, the direct search algorithm based on the recurrence plot shows the advantage of being fast and parameter free. The direct search algorithm, however, relies on quasi-periodicity in input time series, an assumption that limits the algorithm＇s applicability. In this paper, we eliminate the periodicity assumption from the direct search algorithm by proposing a reference function for subsequences and a new sampling strategy based on the reference function. These measures result in a new algorithm with improved efficiency and robustness, as evidenced by our empirical evaluation.

关键词： time series anomaly detection recurrence structure direct discord search parameter-free algorithm

Influence of Glyphaea brevis twig extract on nucleus, tight junctions and expression of inhibin-β, stem cell factor, and androgen binding protein in TM4 Sertoli cells

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Asian pacific Journal of Reproduction 2019年第4期8卷 157-166页

作者： janet Olayemi Olugbodi Oladipupo david Oluwafemi Adeleke Ojo Afolabi Clement Akinmoladun Department of Biochemistry Bingham UniversityAbuja-Keffi RoadKaruNigeria Department of Medical Bioscience University of the Western CapeBellvilleCape TownSouth Africa Phytomedicine and Biochemical Toxicology Unit Department of BiochemistryAfe Babalola UniversityPMB 5454Ado-EkitiNigeria Phytomedicine Biochemical Pharmacology and Toxicology LaboratoriesDepartment of BiochemistrySchool of SciencesPMB 704The Federal University of TechnologyAkureNigeria

Objective: To examine the influence of Glyphaea (G.) brevis twig extract on the mitochondrial dehydrogenase activity, integrity of the tight junctions between adjacent cells, mitochondria, apoptosis, nucleus and expression of inhibin-β, stem cell factor, and androgen binding protein in TM4 Sertoli cells. Methods: TM4 cell line was used in this study as it exhibited properties similar to the Sertoli cells. TM4 Sertoli cells were exposed to G. brevis twig extract (0.1, 1.0, 10.0, 100.0, or 1000.0μg/mL) for 24, 48 and 72 h. Parameters studied included cell viability [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay], mitochondrial membrane potential (tetra methyl rhodamine ethyl ester dye), transepithelial electrical resistance, apoptosis (Annexin V Alexa Fluor?488/propidium iodide assay) and mRNA expression (quantitative reverse transcription polymerase chain reaction). Results: G. brevis twig extract had no cytotoxic impact on cell viability, thus, considerably increasing the activity of mitochondrial dehydrogenase enzyme after 24 and 72 h exposure. Transepithelial electrical resistance values revealed substantial (P<0.05) rise in treated groups, especially after 72 h of treatment. Moreover, there was a significant decrease in mitochondrial depolarization of TM4 Sertoli cells exposed to G. brevis twig extract when compared to controls. In addition, G. brevis twig extract significantly reduced necrosis and apoptosis of TM4 Sertoli cells when compared to control. Nevertheless, fluorescence microscopy revealed that the nuclei were egg-shaped and marked uniformly with consistent cell shape at the middle of the TM4 Sertoli cells. Significant stimulatory effects were observed on mRNA levels of inhibin-β, androgen binding protein and stem cell factor. Conclusions: G. brevis twig extract may increase the secretory roles of TM4 Sertoli cells, cells proliferation, as well as cell-cell tight junction integrity. Thus, G. brevis twig may enhance spermatogenesis

关键词： Glyphaea brevis twig TM4 Sertoli cell line Inhibin-β Androgen binding protein

Evidence of neurodegeneration in autism spectrum disorder

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Translational Neurodegeneration 2013年第1期2卷 113-118页

作者： janet K Kern david A Geier Lisa K Sykes Mark R Geier Institute of Chronic Illnesses IncorporationSilver SpringMDUSA University of Texas Southwestern Medical Center at Dallas DallasTXUSA CoMeD IncorporationSilver SpringMDUSA

Autism spectrum disorder(ASD)is a neurological disorder in which a significant number of children experience a developmental regression characterized by a loss of previously-acquired skills and *** of neurological function in ASD,as observed in affected children who have regressed,can be explained as *** there is research evidence of neurodegeneration or progressive encephalopathy in ASD,the issue of neurodegeneration in ASD is still under *** of neurodegeneration in the brain in ASD includes:(1)neuronal cell loss,(2)activated microglia and astrocytes,(3)proinflammatory cytokines,(4)oxidative stress,and(5)elevated 8-oxo-guanosine *** evidence from this review suggests that neurodegeneration underlies the loss of neurological function in children with ASD who have experienced regression and loss of previously acquired skills and abilities,and that research into treatments to address the issue of neurodegeneration in ASD are warranted.

关键词： Autism spectrum disorder(ASD) Autism Neurodegeneration Regression Neuronal cell loss Microglia Oxidative stress Cytokines

The intermediate water in the Philippine Sea

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Journal of Oceanology and Limnology 2020年第5期38卷 1343-1353页

作者： ZANG Nan WANG Fan SPRINTALL janet CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao 266237China College of Marine Science University of Chinese Academy of SciencesQingdao 266400China Scripps Institution of Oceanography U.C.San DiegoLa Jolla CA 92093-0230U.S.A

The dimensional and temporal distribution of Antarctic Intermediate Water(AAIW)and North Pacifi c Intermediate Water(NPIW)in the Philippine Sea were explored using Argo profi les and gridded Argo *** the salinity minimum of intermediate water from mid-high latitude of the southern and northern hemisphere of the Pacifi c Ocean,the properties of AAIW and NPIW merge at about 10°N with diff erent properties in the Philippine *** core of AAIW is located below 600 dbar with potential density of 27≤σθ≤27.3 kg/m 3 and salinity of 34.5≤S≤*** core of NPIW is located between 300–700 dbar with potential density of 26.2≤σθ≤27 kg/m 3 and salinity of 34≤S≤*** volume of AAIW and NPIW during January 2004 to December 2017 is negatively *** time series of AAIW and NPIW is dominated by signifi cant periods of 6 and 8 months,*** variations of AAIW and NPIW are mainly aff ected by volume transport through a 130°E section by the North Equatorial Current(NEC)and North Equatorial Undercurrent(NEUC).

关键词： the intermediate water the Antarctic Intermediate Water the North Pacifi c Intermediate Water seasonal variation

Cultural Studies:Return to Beauty——An Interview with Professor janet Wolff

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马克思主义美学研究 2012年第1期15卷 187-197页

作者： janet Wolff Manchester University Shanghai Jiaotong University

珍妮特·伍尔芙(janet Wolff)是曼彻斯特大学文化社会学荣誉退休教授,2008-2010年担任曼彻斯特大学跨学科艺术研究中心主任。主要研究领域涉及社会学、文化研究、视觉文化、女性主义等。2012年4月珍妮特·伍尔芙参加了在英国曼彻斯特大... 详细信息

珍妮特·伍尔芙(janet Wolff)是曼彻斯特大学文化社会学荣誉退休教授,2008-2010年担任曼彻斯特大学跨学科艺术研究中心主任。主要研究领域涉及社会学、文化研究、视觉文化、女性主义等。2012年4月珍妮特·伍尔芙参加了在英国曼彻斯特大学举行的第二届中英马克思主义美学研究双边论坛。并发表了有关文化研究的社会学问题的专题演讲,在这次演讲之后,我们对她做了此次访谈。这个访谈围绕着文化研究的社会学研究领域展开,探讨了文化研究中的批判理论与女性主义美学价值问题,并进一步探讨了在当代文化社会学研究与审美的相关问题域中如何展开审美分析的问题。

关键词：文化研究批判理论女性主义社会学审美