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双螺杆挤压机螺杆元件类型对扭矩和压力的影响

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农业机械学报 2007年第9期38卷 71-74,58页

作者：张波魏益民 wolfgang sietze Jens Dreisoerner 康立宁中国农科院农产品加工研究所德国布拉本德仪器公司食品实验室西北农林科技大学食品科学与工程学院

以食用脱脂低温豆粕为原料,以Brabender DSE-25型双螺杆挤压膨化实验室工作站为加工设备,研究了不同几何参数的输送元件、捏合块和齿型盘6种螺杆元件对挤压过程中扭矩和压力的影响。结果表明:螺杆元件对扭矩和压力有显著影响;对扭矩影... 详细信息

以食用脱脂低温豆粕为原料,以Brabender DSE-25型双螺杆挤压膨化实验室工作站为加工设备,研究了不同几何参数的输送元件、捏合块和齿型盘6种螺杆元件对挤压过程中扭矩和压力的影响。结果表明:螺杆元件对扭矩和压力有显著影响;对扭矩影响的主次顺序为反向输送元件;齿型盘、捏合块、正向输送元件;有反向螺旋角或错裂角或对物料剪切强度大的元件能够显著增加扭矩;元件对压力的影响规律不明显。对系统稳定性的初步分析认为,错列角为45°和90°的捏合块具有较好的混炼效果,而齿型盘和错列角为-45°的捏合块的混炼效果较差。

关键词：双螺杆挤压机螺杆元件扭矩压力

Towards engineering a portable platform for laparoscopic pre-training in virtual reality with haptic feedback

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虚拟现实与智能硬件（中英文） 2024年第2期6卷 83-99页

作者： Hans-Georg ENKLER wolfgang KUNERT Stefan PFEFFER Kai-Jonas BOCK Steffen AXT Jonas JOHANNINK Christoph REICH Furtwangen University 78120 FurtwangenGermany University Hospital and Faculty of Medicine Tuebingen 72076 TuebingenGermany

Background Laparoscopic surgery is a surgical technique in which special instruments are inserted through small incision holes inside the body.For some time,efforts have been made to improve surgical pre training through practical exercises on abstracted and reduced models.Methods The authors strive for a portable,easy to use and cost-effective Virtual Reality-based(VR)laparoscopic pre-training platform and therefore address the question of how such a system has to be designed to achieve the quality of today's gold standard using real tissue specimens.Current VR controllers are limited regarding haptic feedback.Since haptic feedback is necessary or at least beneficial for laparoscopic surgery training,the platform to be developed consists of a newly designed prototype laparoscopic VR controller with haptic feedback,a commercially available head-mounted display,a VR environment for simulating a laparoscopic surgery,and a training concept.Results To take full advantage of benefits such as repeatability and cost-effectiveness of VR-based training,the system shall not require a tissue sample for haptic feedback.It is currently calculated and visually displayed to the user in the VR environment.On the prototype controller,a first axis was provided with perceptible feedback for test purposes.Two of the prototype VR controllers can be combined to simulate a typical both-handed use case,e.g.,laparoscopic suturing.A Unity based VR prototype allows the execution of simple standard pre-trainings.Conclusions The first prototype enables full operation of a virtual laparoscopic instrument in VR.In addition,the simulation can compute simple interaction forces.Major challenges lie in a realistic real-time tissue simulation and calculation of forces for the haptic feedback.Mechanical weaknesses were identified in the first hardware prototype,which will be improved in subsequent versions.All degrees of freedom of the controller are to be provided with haptic feedback.To make forces tangible in the simulation,characteristic values

关键词： Laparoscopic surgery Training Virtual reality Controller Haptic feedback Kinesthetic skills

A Maintenance Service Improvement Approach Based on Queue Networks: Application

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Open Journal of Applied Sciences 2024年第2期14卷 425-440页

作者： Aslain Brisco Ngnassi Djami wolfgang Nzié Boukar Ousman Joseph Nkongho Anyi Ulrich Ngnassi Nguelcheu Department of Fundamental Sciences and Techniques of Engineer Chemical Engineering and Mineral Industries School University of Ngaoundere Ngaoundere Cameroon Laboratory of Mechanics Materials and Photonics National School of Agro-Industrial Sciences University of Ngaoundere Ngaoundere Cameroon Department of Electrical Engineering Energy and Automation National School of Agro-Industrial Sciences University of Ngaoundere Ngaoundere Cameroon Laboratory E3M Faculty of Industrial Engineering University of Douala Douala Cameroon Department of Physics Faculty of Science University of Ngaoundere Ngaoundere Cameroon

The quest to increase the performance of production systems that have become complex leads to the transfer to the maintenance function of the responsibility of guaranteeing the availability of such systems. Also, we will never stop saying that maintenance must integrate into all of the company’s initiatives, to affirm its role, which is to ensure greater availability and sustainability of the means of production. The objective of this paper is to evaluate the reliability and availability of a system without knowing the distribution law of the operating times. Among the methods for evaluating dependability criteria (Fault Trees, Petri Nets, etc.), we are interested in queues that have the advantage of taking into account functional dependencies, thus allowing a quantified optimization of maintenance. Indeed, queues make it possible to model parallel or sequential processes, implementing operations taking place at the same time or one after the other, meeting the needs of modeling production systems. The main result of this paper is the study of the influence of availability on the reliability of a multi-state production system.

关键词： Markov Chains Queues Availability Reliability Maintenance

Evaluation of the Reliability of a System: Approach by Monte Carlo Simulation and Application

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Open Journal of Applied Sciences 2024年第3期14卷 721-739页

作者： Aslain Brisco Ngnassi Djami Jean Bosco Samon Boukar Ousman Ulrich Ngnassi Nguelcheu wolfgang Nzié Guy Edgar Ntamack Bienvenu Kenmeugne Department of Fundamental Sciences and Techniques of Engineer Chemical Engineering and Mineral Industries School University of Ngaoundere Ngaoundere Cameroon Department of Mechanical Engineering National School of Agro-Industrial Sciences University of Ngaoundere Ngaoundere Cameroon Department of Electrical Engineering Energy and Automation National School of Agro-Industrial Sciences University of Ngaoundere Ngaoundere Cameroon Department of Physics Faculty of Science University of Ngaoundere Ngaoundere Cameroon Department of Industrial and Mechanical Engineering National Advanced School of Engineering University of Yaounde I Yaounde Cameroon

The objective of this paper is to evaluate the reliability of a system in its different states (absence of failures, partial failure and total failure) and to propose actions to improve this reliability by an approach based on Monte Carlo simulation. It consists of a probabilistic evaluation based on Markov Chains. In order to achieve this goal, the functionalities of Markov Chains and Monte Carlo simulation steps are deployed. The application is made on a production system. .

关键词： Evaluation Reliability Monte Carlo Markov Chain

《欧盟人工智能法案》的背景、主要内容与评价——兼论该法案对劳动法的影响

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环球法律评论 2024年第3期46卷 5-27页

作者： [德]沃尔夫冈·多伊普勒德国不来梅大学法学院

为了应对人工智能系统带来的各种挑战,《欧盟人工智能法案》采用基于风险分类的监管路径。法案首先明确禁止了某些存在不可接受风险的人工智能系统,然后重点规制高风险人工智能系统,任何在欧盟市场上提供此类系统的企业都必须满足法案... 详细信息

为了应对人工智能系统带来的各种挑战,《欧盟人工智能法案》采用基于风险分类的监管路径。法案首先明确禁止了某些存在不可接受风险的人工智能系统,然后重点规制高风险人工智能系统,任何在欧盟市场上提供此类系统的企业都必须满足法案规定的从风险管理、数据治理到全面的记录义务等诸多要求。但是,法案的监管要求可能造成小微企业负担过重,模糊的规定也可能导致实施方面的困难。在劳动关系领域,对雇员进行社会评分、预测雇员犯罪风险、分析雇员情绪等人工智能系统可能因为存在不可接受的风险而被禁止。对岗位申请者和雇员使用人工智能系统的,则根据是否属于高风险系统而负担不同的义务。除了要让雇主向雇员提供相关人工智能技能培训以外,工作中使用ChatGPT的问题也值得关注。

关键词：欧盟人工智能法案风险分类劳动法 ChatGPT

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德国南部钻石城太空送来的七万吨礼物

环球人文地理 2024年第3期 96-103页

作者：袁莘捷 lebaer wolfgang Ralf ArTo konrad filbert Andrey＿Lobachev Sina Ettmer flickr

钻石受到无数人追捧，其高昂的价格也让人望而却步。让人意外的是，在德国巴伐利亚州的西部山区，人们竟用七万吨钻石，建造了一座闪闪发光的钻石城。诺德林根是一座中世纪小镇，距今已有上千年历史。这里四面都有围墙，是德国目前仅有...

钻石受到无数人追捧，其高昂的价格也让人望而却步。让人意外的是，在德国巴伐利亚州的西部山区，人们竟用七万吨钻石，建造了一座闪闪发光的钻石城。诺德林根是一座中世纪小镇，距今已有上千年历史。这里四面都有围墙，是德国目前仅有的三座完全被城墙环绕的城市之一。小镇曾经安宁祥和，也曾经饱经硝烟，而许多建筑，甚至差点毁于一场大火。

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Hidden in the parts:How the cell-type perspective reveals novel insights into plant-microbe interactions

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Molecular Plant 2023年第9期16卷 1359-1362页

作者： Christian Froschel wolfgang Droge-Laser Pharmaceutical Biology Julius-von-Sachs-InstituteJulius-Maximilians-Universitat WurzburgJulius-von-Sachs Platz 297082 WurzburgGermany Present address:Botany ll Julius-von-Sachs-lnstituteJulius-Maximilians-Universitat WurzburgJulius-von-Sachs Platz 397082 WurzburgGermany

The origin of multicellularity is considered an evolutionary milestone,as cellular differentiation and cooperation have allowed the emergence of specialized and unique functions.Some crucial biological processes involve only a few cells,making it difficult to detect specific transcriptional signatures in classical bulk tissue studies.Important information often remains hidden in the sum of thousands of cells,and thus localized studies are essential.Although plant responses to microbes are well known to occur highly localized(Emonet et al.,2021),approaches to describe their impact at a cellular level have been established only very recently.Applying single-cell transcriptomics,Verbon et al.,2023 addressed this topic and disclosed heterogeneous responses of root cells when colonized by the beneficial bacterium Pseudomonas simiae.Focusing on Arabidopsis,we here compare this study with some groundbreaking methodological advances and provides perspectives on upcoming endeavors(Figure 1).

关键词： Figure insight specialized

Latency arbitrage and the synchronized placement of orders

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Financial Innovation 2023年第1期9卷 2650-2667页

作者： wolfgang Kuhle Department of Economics Corvinus UniversityBudapestHungary MEA Max Planck Institute for Social Law and Social PolicyMunichGermany Zhejiang University HangzhouChina

We argue that owing to traders’inability to fully express their preferences over the execution times of their orders,contemporary stock market designs are prone to latency arbitrage.In turn,we propose a new order type,which allows traders to specify the time at which their orders are executed after reaching the exchange.Using recent latency data,we demonstrate that the order type proposed here allows traders to synchronize order executions across different exchanges,such that high-frequency traders,even if they operate at the speed of light,can no-longer engage in latency arbitrage.

关键词： Market design High-frequency trading Latency arbitrage

Long-term monitoring data reveal effects of age,population density,and environmental aspects on hatching success of Common Cranes(Grus grus)

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Avian Research 2022年第3期13卷 347-355页

作者： Isabel Barwisch wolfgang Mewes Angela Schmitz Ornes AG Vogelwarte Zoological Institute and MuseumUniversity of GreifswaldSoldmannstr.23GreifswaldGermany Grüner Weg 3 19395Plau Am SeeOT KarowGermany

Facing climate and land use change,a species’ability to successfully adapt to changing environments is crucial for its survival.Extensive drainage and intensification of agriculture and forestry set wetlands and associated species at risk of population declines.The population of Common Cranes(Grus grus)has experienced considerable fluctuations over the last century.Despite increasing population numbers,hatching success seemed to have decreased over the last years.The aim of this study was to identify factors influencing hatching success and nest survival of Common Cranes based on analyses of long-term individual-based monitoring data from northeastern Germany and evaluate the species ability to adapt to changing environments.Hatching success decreased over the course of the study period from 0.75 to 0.55.Surprisingly,nest survival and hatching success did not vary across different nesting habitats,whereas factors such as female age,timing of nest initiation and breeding pair density were found to have significant effects on hatching success.Older females showed higher hatching success,even though the proportion of unhatched eggs was highest in females aged 20 years or older.Early nest initiation had a positive effect on hatching success.Water levels are more favorable early in the nesting season,whereas increasing evaporation with time causes water levels to decrease,granting easier access for predators.Independently of female age,hatching success decreased with increasing numbers of breeding pairs within a 2-km radius around a nesting site.High population densities intensify competition for resources and promote intraspecific interactions,affecting reproductive outcome negatively.This study gives first insights into mechanisms behind population regulation in Common Cranes,highlighting the importance of population dynamics and individual features.We suggest to further investigate density dependent effects including landscape and habitat features as well as reproductive success in terms of chick survival,since suc

关键词： Adaptation Age Cranes Grus grus Habitat Nest survival Population density Reproduction