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list:PA6生产中的高粘度熔融工艺

国际纺织导报 2001年第Z1期29卷 51-51页

作者： A.Diener list Germany G.Raouzeos 张耀鹏沈新元 list公司瑞士 List公司瑞士 List公司瑞士　　

目前聚酰胺6(PA6)的生产工艺中除了VK反应器之外,还包括己内酰胺的萃取、干燥和固态下后缩合等几步后处理工序.瑞士的list公司最近在PA6的中试规模生产工艺上取得了较大的成功,使相对粘度值达到了4.0.……

关键词：生产工艺高粘度后处理工序中试规模己内酰胺粘度值聚酰胺反应器缩合瑞士固态干燥萃取

Real-time temperature prediction of electric machines using machine learning with physically informed features

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Energy and AI 2023年第4期14卷 415-425页

作者： Ryan Hughes Thomas Haidinger Xiaoze Pei Christopher Vagg University of Bath UK AVL list GmbH Austria

Accurate estimation of the internal temperatures of electric machines is critical to increasing their power density and reliability since key temperatures,such as magnet temperature,are often difficult to *** work presents a new machine learning based modelling approach,incorporating novel physically informed feature engineering,which achieves best-in-class accuracy and reduced training *** different features introduced are proportional to sources of machine losses and require no prior knowledge of the machine,hence the models are completely data *** using a standard experimental dataset shows that modelling errors can be reduced by up to 82.5%,resulting in the lowest mean squared error recorded in the literature of 2.40 K^(2).Additionally,models can be trained with less training data and have lower sensitivity to data ***-ically,it was possible to train a loss enhanced multilayer perceptron model to a mean squared error<5 K^(2) with 90 h of training data,and an enhanced ordinary least squares model with just 60 h to the same *** inference time of the model can be 1–2 orders of magnitude faster than competing models and requires no time to optimise hyperparameters,compared to weeks or months for other state-of-the-art prediction *** results are highly important for enabling low-cost real-time temperature monitoring of electric machines to improve operational efficiency,safety,reliability,and power density.

关键词： Thermal model Real-time Electric machine Machine learning Losses

Why responses to dramatic climate change are important？

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Current Zoology 2011年第3期57卷 350-350页

作者： Anders Pape Moller No list

Climate change is proceeding at an unprecedented pace with global temperatures and sea-levels setting new records almost every year （IPCC, 2007）. While these changes are worrisome due to effects on all biological systems and hence also on humans, even more problematic changes may be in the waiting, because not only is the climate changing, but it is also becoming more extreme. Extreme temperatures, rainfall, droughts, storms and fires are already becoming more common with severe consequences for humans, their crops and domestic animals and all wild organisms. For example, the severe heat wave in 2003 caused an excess mortality of 2,600 humans in France alone （INSERM, 2003）, and primary production was suppressed across Europe （Ciais et al. 2004）.

关键词：气候变化反应 IPCC 全球气温生物系统野生生物初级生产海平面

Cumulative unsupervised multi-domain adaptation for Holstein cattle re-identification

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Artificial Intelligence in Agriculture 2023年第4期10卷 46-60页

作者： Fabian Dubourvieux Guillaume Lapouge Angélique Loesch Bertrand Luvison Romaric Audigier UniversitéParis-Saclay CEA ListPalaiseau 91120France LITIS INSA RouenNormandie UniversitéSaint-Etienne-du-Rouvray 76801France

In dairy farming,ensuring the health of each cow and minimizing economic losses requires individual monitoring,achieved through cow Re-Identification(Re-ID).Computer vision-based Re-ID relies on visually dis-tinguishing features,such as the distinctive coat patterns of breeds like ***,annotating every cow in each farm is *** objective is to develop Re-ID methods applicable to both labeled and unlabeled farms,accommodating new individuals and diverse ***-supervised Domain Adaptation(UDA)techniques bridge this gap,transferring knowledge from labeled source domains to unlabeled target domains,but have only been mainly designed for pedestrian and vehicle Re-ID *** work introduces Cumulative Unsupervised Multi-Domain Adaptation(CUMDA)to address challenges of lim-ited identity diversity and diverse farm *** accumulates knowledge from all domains,enhanc-ing specialization in known domains and improving generalization to unseen *** contributions include a CUMDA method adapting to multiple unlabeled target domains while preserving source domain performance,along with extensive cross-dataset experiments on three cattle Re-ID *** experiments demonstrate significant enhancements in source preservation,target domain specialization,and generalization to unseen domains.

关键词： Re-identification Domain adaptation Holstein cattle Unsupervised learning Monitoring

Coupling of 3D Eulerian and Lagrangian Spray Approaches in Industrial Combustion Engine Simulations

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Journal of Energy and Power Engineering 2014年第1期8卷 190-200页

作者： Wilfried Edelbauer A VL list GmbH Hans List Platz 1 Graz AT-8020 Austria

The Lagrangian DDM （discrete droplet model） is state-of-the-art for CFD （computational fluid dynamics） simulations of mixture formation and combustion in industrial engines. A commonly known drawback of the DDM approach is the attenuated validity in the dense spray, where the bulk liquid disintegrates into droplets. There the assumption of single droplets surrounded by a homogenous gas field is not reasonable. In this region, the Eulerian-Eulerian multi-phase approach performs better because instead of parcels the spray is represented by the volume fractions of one bulk liquid and several droplet size class phases. A further drawback of the DDM approach is that increasing the spatial resolution of the computational grid leads to a reduced statistical convergence, since the number of spray parcels per computational cell becomes smaller. It is desirable to combine the benefits of both spray approaches in coupled CFD simulations. Therefore, the dense spray region is simulated separately with the Eulerian spray approach on a highly resolved mesh covering only the region close to the nozzle orifice. The entire engine domain with combustion and emission models is simulated with the Eulerian-Lagrangian spray approach for the dilute spray region. The two simulations are coupled through exchange of boundary conditions and model source terms. An on-line coupling interface manages the data transfer between the two simulation clients, i.e., Eulerian spray and engine client. The aim of this work is to extend the coupled spray approach in terms of exchanging combustion related heat and species sources, and consequently creating the link between Eulerian spray and combustion models. The results show mixture formation and combustion in real-case engine simulations, and demonstrate the feasibility of spray model combination in engineering applications.

关键词： CFD code coupling combustion Eulerian spray Lagrangian spray multi-fluid approach.

Dynamic Parameters Cellular Automaton Model for Passengers in Subway

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Tsinghua Science and Technology 2015年第6期20卷 594-601页

作者： Yichen Zheng Xiangyu Xi Yifan Zhuang Yi Zhang Department of Automation Tsinghua National Laboratory for Information Science and Technology (TN List)Tsinghua University National Engineering Research Center of Software Engineering Peking University Tsinghua University

To simulate the passenger behavior in subway system, a Dynamic Parameters Cellular Automaton(DPCA) model is put forward in this paper. Pedestrian traffic flows during waiting, getting on or off, and traveling can be simulated. The typical scenario in Beijing Subway Line 13 is modeled to analyze the passenger behavior in subway system. By comparing simulation results with statistical ones, the correctness and practicality of the DPCA model are verified. At last, the additional results made by DPCA model can make contribution to passenger comfort analysis and pedestrian facility planning and guidance.

关键词： pedestrian stream subway cellular automaton dynami

Optofluidic transport and assembly of nanoparticles using an all-dielectric quasi-BIC metasurface

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Light(Science & Applications) 2023年第9期12卷 1771-1781页

作者： Sen Yang Justus C.Ndukaife Department of Electrical and Computer Engineering Vanderbilt UniversityNashvilleTNUSA Interdisciplinary Materials Science Vanderbilt UniversityNashvilleTNUSA Full list of author information is available at the end of the article

Manipulating fluids by light at the micro/nanoscale has been a long-sought-after goal for lab-on-a-chip *** heating has been demonstrated to control microfluidic dynamics due to the enhanced and confined light absorption from the intrinsic losses of ***,the counterpart of metals,has been used to avoid undesired thermal effects due to its negligible light ***,we report an innovative optofluidic system that leverages a quasi-BIC-driven all-dielectric metasurface to achieve subwavelength scale control of temperature and fluid *** experiments show that suspended particles down to 200 nanometers can be rapidly aggregated to the center of the illuminated metasurface with a velocity of tens of micrometers per second,and up to millimeter-scale particle transport is *** strong electromagnetic field enhancement of the quasi-BIC resonance increases the flow velocity up to three times compared with the off-resonant situation by tuning the wavelength within several nanometers *** also experimentally investigate the dynamics of particle aggregation with respect to laser wavelength and power.A physical model is presented and simulated to elucidate the phenomena and surfactants are added to the nanoparticle colloid to validate the *** study demonstrates the application of the recently emerged all-dielectric thermonanophotonics in dealing with functional liquids and opens new frontiers in harnessing non-plasmonic nanophotonics to manipulate microfluidic ***,the synergistic effects of optofluidics and high-Q all-dielectric nanostructures hold enormous potential in high-sensitivity biosensing applications.

关键词： dielectric quasi negligible

Resignation of officials as independent directors and firm performance

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Frontiers of Business Research in China 2020年第4期14卷 498-518页

作者： Ting Ren Youzhi Xiao Xinguo Yu Hongyan Yang Jianmei Ge HSBC Business School Peking UniversityShenzhenChina Full list of author information is available at the end of the article

In 2013,the Chinese government implemented Rule No.18,which suspended the directorships of incumbent government officials and precluded those who retired within the past three years from serving as independent directors for listed *** surprise implementation of Rule No.18 triggered a wave of resignations among official independent directors(OIDs).The event provided a unique opportunity to examine the impacts of the political connections of board members on firm *** applied a difference-in-difference technique to empirically investigate the effect of OID resignations on firm performance from the perspectives of resource dependence theory and social capital *** results indicate that the resignation of OIDs had a significantly negative effect on firm performance,as measured by Tobin's 0 and firm *** also confirmed the importance of independent directors'political connection on firm performance,as discovered in prior ***,this influence varied across OIDs'heterogeneity,external environment and firm *** results indicate that political connections may not be necessary channels for firms to achieve success.

关键词： Firm performance Independent director Political connection Resource dependence theory Social capital theory

Chinese employees＇ leadership preferences and the relationship with power distance orientation and core self-evaluation

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Frontiers of Business Research in China 2018年第1期12卷 15-36页

作者： Cai-Hui Veronica Lin Jian-Min James Sun School of Labor and HumanResources Renmin University ofChina Beijing China Full list ofauthor information isavailable at the end of the article

Informed by implicit leadership theories, this study investigates contemporary Chinese employees＇ preferences for paternalistic leadership （including three components： moral leadership, benevolent leadership and authoritarian leadership） and transformational leadership. It further examines the relationship between power distance orientation, core self-evaluation （CSE） and leadership preferences. The study finds that contemporary Chinese employees most prefer moral leadership, but are also highly receptive to transformational leadership. They prefer authoritarian leadership least. Moreover, preferences for authoritarian leadership are predicated on followers＇ power distance orientation. However, the opposite is true for moral leadership. CSE is positively related to followers＇ preference for authoritarian leadership, benevolent leadership and transformational leadership, but not except for moral leadership. A positive interaction effect is found between power distance orientation and CSE with regard to authoritarian leadership preference. The theoretical and practical implications of the findings are discussed.

关键词： Contemporary Chinese employees Leadership preference Power distanceorientation Core self-evaluation (CES)