检索结果-内蒙古大学图书馆

Investigating Measures on Space Heating and Domestic Hot Water Preparation systems in Residential Buildings Regarding their Impact on the Total Heat Demand and Return Temperatures in District Heating Networks

Investigating Measures on Space Heating and Domestic Hot Wat...

引用

ISES Solar World Congress 2021

作者： Braas, H. Graf, C. Yu, Y. Orozaliev, J. Jordan, U. Vajen, K. University of Kassel Institute of Thermal Engineering Department of Solar and Systems Engineering Germany Fraunhofer Institute for Energy Economics and Energy System Technology Department of Thermal Energy System Technology Kassel Germany

ISBN: (纸本)9783982040875

District heating can contribute substantially to a cost-effective decarbonization of the heating sector. Lowering the temperature levels of district heating systems is an important requirement for the efficient utilization of renewable energy sources. As return temperature reductions must precede flow temperature reductions, the consumers in a district heating system play a major role. This simulation study takes a closer look at four exemplary buildings space heating and domestic hot water preparation systems using TRNSYS and investigates influences on the total heat demand and return temperatures. In buildings with high energy efficiency standards the domestic hot water preparation makes up about half of the total heat demand and therefore has a very high impact on the total return temperatures. By reducing the circulation heat losses and switching from storage systems to instantaneous domestic hot water preparation, return temperatures can be reduced significantly. In existing buildings, with higher space heating demand, the space heating system design is a key driver for the total return temperatures. However, user behaviour and especially faults, like unnecessary bypasses also have significant influences and can raise return temperatures. © 2021. The Authors. Published by International Solar Energy Society Selection and/or peer review under responsibility of Scientific Committee.

关键词： District heating

来源：评论

学校读者我要写书评

暂无评论

Table-top coherent XUV source with a brightness of 1kW/(mm2sr)/1%BW at 130eV

Table-top coherent XUV source with a brightness of 1kW/(mm2s...

引用

Compact EUV and X-Ray Light Sources, EUVXRAY 2024 - Part of Optica High-Brightness Sources and Light-Driven Interactions Congress

作者： Tschernajew, Maxim Hilbert, Vinzenz Klas, Robert Herrfurth, Oliver Breitkopf, Sven Rothhardt, Jan Eidam, Tino Limpert, Jens Active Fiber Systems GmbH Ernst-Ruska-Ring 17 Jena07745 Germany Institute of Applied Physics Abbe Center of Photonics Friedrich-Schiller-Universität Jena Albert-Einstein-Str. 15 Jena07745 Germany Helmholtz-Institute Jena Fröbelstieg 3 Jena07743 Germany Fraunhofer Institute for Applied Optics and Precision Engineering Albert-Einstein-Str. 7 Jena07745 Germany

We present a highly stable, easy-to-use, table-top coherent XUV source delivering a brightness of >1kW/(mm2sr)/1%BW at 130eV (9.5nm). IT is based on high-harmonic generation driven by an ultrastable Ytterbium-dope ... 详细信息

关键词： Fiber lasers

来源：评论

学校读者我要写书评

暂无评论

Shaping smart intermodality between waterborne and landside transport in the coastal city of stavanger

Shaping smart intermodality between waterborne and landside ...

引用

2021 IEEE European Technology and engineering Management Summit, E-TEMS 2021

作者： Sachs, Carolina Azevedo, Andreia Lopes Dahle, Mikal Henriksen, Espen Strand Fraunhofer Institute for Industrial Engineering IAO Mobility and Innovation Systems Stuttgart Germany Kolumbus AS TrAM Project Management Stavanger Norway

ISBN: (纸本)9781665419789

Worldwide, waterborne transport is the most efficient choice for moving goods in terms of tonnes per kilometer. In Europe, especially in the Nordic countries, it is a relevant mobility means for passenger traffic too, used mainly for commuting activities. Most of the vessels operating on coastal and inland waterways, for either goods or passenger transport, are equipped with conventional diesel powertrains that negatively affect the environment and endanger the well-being of the population that live and work in their immediate surroundings. Through legislation and funding programs, electrification of ferries and larger vessels has already begun and should contribute to the achievement of carbon neutral shipping in Europe by 2050. The integration of electrified vessels into existing mobility systems and urban infrastructure to optimize passenger journeys and cargo transport represents an additional challenge. With the use case of the coastal city of Stavanger, this paper presents an approach to identify and evaluate mobility services and accessibility issues with the purpose of enhancing intermodality between waterborne and landside passenger transport. © 2021 IEEE.

关键词： Smart city

来源：评论

学校读者我要写书评

暂无评论

Development of a mechanical, biocide-free method of disinfection for cathodic dip coating processes 21

Development of a mechanical, biocide-free method of disinfec...

引用

21st International Conference of the European Society for Precision engineering and Nanotechnology, EUSPEN 2021

作者： Uhlmann, E. Hilt, M. Hein, C. Cudazzo, M. Huth-Herms, K. Jahnke, C. Quast, M. Fraunhofer Institute for Production Systems and Design Technology IPK Germany Fraunhofer Institute for Manufacturing Engineering and Automation IPA Germany Institute for Machine Tools Factory Management IWF Technische Universität Berlin Germany

ISBN: (纸本)9780995775190

Technical fluids are often contaminated by bacteria as Burkholderia cepacia (B. cepacia), which is found in different industrial issues and affects manufacturing process chains by the formation of planktonic cell-aggregates and biofilms within the working fluids. B. cepacia is one of nine species of the Burkholderia cepacia complex (Bcc), a group of gram-negative, motile, non-spore-forming, and rod-shaped bacteria. Because of the opportunistic pathogenicity to plants, animals, humans, and the multi-drug and biocide resistance, B. cepacia is difficult to treat. This study aims to provide an application to reduce the germ numbers ng in an eco-friendly and continuous process without the use of biocides. The approach to disinfect technical fluids is to apply high shear forces in a rotor-stator assembly to the fluid. A prototype of the rotor-stator assembly with a variably adjustable shear gap gs and rotor speed srot was constructed. First experiments with a frequency frot 10 Hz ≤ frot ≤ 40 Hz a shear gap gs = 83 µm and gs = 166 µm showed a reduction of germ number ngr = 99.6 %. It concluded that the disinfection of technical fluids by a rotor-stator assembly is a biocide-free alternative. In addition to defined process parameters such as shear gap gS, temperature ϑ, frequency frot and time of machining process tmp, also the peripheral speed vp, rotational speed vrot, flow rate fr and shear stresses τ were used to assess the machining result and to develop an overall concept for disinfection of technical fluids. © 2021 Proceedings of the 21st International Conference of the European Society for Precision engineering and Nanotechnology, EUSPEN 2021. All rights reserved.

关键词： Stators

来源：评论

学校读者我要写书评

暂无评论

Managing the Inner Workings of Collective Intelligence Approaches for Wicked Problems – An Assessment Model and Evaluation

引用

Communications of the Association for Information systems 2023年 52卷 1-1页

作者： Gimpel, Henner Laubacher, Robert Schoch, Manfred Parak, Dominik Wöhl, Moritz University of Hohenheim FIM Research Center for Information Management Fraunhofer Institute for Applied Information Technology FIT Branch Business & Information Systems Engineering Germany Center for Collective Intelligence Massachusetts Institute of Technology United States Dominik Parak University of Augsburg Germany University of Augsburg FIM Research Center for Information Management Fraunhofer Institute for Applied Information Technology FIT Branch Business & Information Systems Engineering Germany

Ill-defined and complex problems that affect multiple stakeholders with potentially conflicting perspectives are often referred to as wicked problems. The utilization of collective intelligence (CI) via web-based platforms is a promising approach for addressing such wicked problems. The management of these information systems would benefit from evidence-based decision support regarding facilitation and improvement efforts. However, to date, there is no suitable model to guide such efforts. Existing approaches address specific applications or cover certain assessment areas but do not provide a holistic perspective. Meanwhile, research offers substantial insights into best practices for addressing wicked problems and running CI applications. This paper develops an assessment model comprising five central success dimensions for information systems that address wicked problems. Their subdimensions and associated measurement metrics allow for evidence-driven facilitation and improvement of CI applications for wicked problems. Apart from the model’s capability to improve future runs and processes, it also offers the potential to provide immediate insights for facilitation efforts during runtime. The model was validated with a platform dealing with the assessment of risks presented by global climate change. This evaluation generated strong evidence for the model’s applicability and usefulness. © 2023 by the Association for Information systems.

关键词： Information systems

来源：评论

学校读者我要写书评

暂无评论

Survey on Robotic systems Integration

Survey on Robotic Systems Integration

引用

Workshop on Robotics Software engineering (RoSE)

作者： Nadia Hammoudeh Garcia Andreas Wortmann Robot and Assistive Systems Department Fraunhofer Institute for Manufacturing Engineering and Automation (IPA) 70569 Stuttgart Germany Institute for Control Engineering of Machine Tools and Manufacturing Units (ISW) University of Stuttgart 70174 Stuttgart Germany

Software integration is central to successfully developing, deploying, and operating robotics applications. Yet, the particular integration process and its challenges are poorly understood. The continuous evolution of the robotics sector, incorporating constantly a growing number of technologies, makes the unification of processes increasingly complicated. Nevertheless, current research on robotics software integration largely focuses on specific integration activities instead of considering the overall activity as a process. To provide some insight into the state of robotics software integration, we drove a survey among researchers and practitioners in the field. In this survey, we inquired how robotics software integration is currently performed in order to identify similarities with traditional software development methodologies. Through this study, we discovered commonalities in the phases of the process and potential directions of a future research to address the current challenges in the area.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Digital Twin for Industrial Asset Management: A Case Study for Pipeline Maintenance

Digital Twin for Industrial Asset Management: A Case Study f...

引用

Annual Conference of Industrial Electronics Society

作者： Ling Bai Rakiba Rayhana Jiatong Ling Teng Wang Zheng Liu Andreas Schnabel Chunsheng Yang Min Liao School of Engineering University of British Columbia Kelowna BC Canada Fraunhofer Institute for Ceramic Technologies and Systems IKTS Dresden Germany National Research Council of Canada Ottawa ON Canada

ISBN: (数字)9781665464543

ISBN: (纸本)9781665464550

Industrial asset management (IAM) is crucial for the sustainability and efficiency of industries that depend on significant infrastructure, especially pipelines. Pipelines are vital assets in the global energy supply chain, transporting oil, natural gas, and chemical products, and their maintenance is essential to prevent severe environmental and economic consequences. However, current methods such as manual visual inspections are limited by their invasiveness, the requirement for periodic shutdowns, and a lack of real-time accuracy. These limitations present substantial challenges to effective IAM. This paper introduces an innovative digital twin ecosystem integrated with information and communication technology to enhance IAM for pipelines. This ecosystem creates a dynamic, interactive digital twin that accurately reflects the physical state of pipelines, bolstered by real-time data transmission from sensors. The ecosystem comprises physical pipelines equipped with sensors, a comprehensive data knowledge library that records and updates damage information, a virtual pipeline twin, and an interactive platform that facilitates detailed visualization and interaction. Through a detailed case study of pipeline damage detection on cracks and corrosion using visual imaging techniques, this paper demonstrates enhanced results and visualizations compared to existing methods. The observed damage features sharper contrasts, higher resolution, and clearer boundaries in affected areas, significantly improving the accuracy of damage localization. Additionally, the relative accuracy of the calculated damage stress intensity factor by the virtual twin model reaches 95%. In summary, the capabilities for real-time, remote interaction and comprehensive visualization within the digital twin ecosystem significantly enhance the management efficiency of digital and intelligent pipeline IAM.

关键词： Visualization Accuracy Pipelines Ecosystems Data visualization Predictive models Real-time systems Libraries Digital twins Maintenance

来源：评论

学校读者我要写书评

暂无评论

ILP-based Resource Optimization Realized by Quantum Annealing for Optical Wide-area Communication Networks – A Framework for Solving Combinatorial Problems of a Real-world Application by Quantum Annealing

arXiv

引用

arXiv 2024年

作者： Witt, Arthur Kim, Jangho Körber, Christopher Luu, Thomas Institute of Communication Networks and Computer Engineering University of Stuttgart Stuttgart Germany JARA HPC Forschungszentrum Jülich Jülich Germany Fraunhofer Research Institution for Energy Infrastructures and Geothermal Systems IEG Fraunhofer IEG Bochum Germany

Resource allocation of wide-area internet networks is inherently a combinatorial optimization problem that if solved quickly, could provide near real-time adaptive control of internet-protocol traffic ensuring increased network efficacy and robustness, while minimizing energy requirements coming from power-hungry transceivers. In recent works we demonstrated how such a problem could be cast as a quadratic unconstrained binary optimization (QUBO) problem that can be embedded onto the D-Wave Advantage™ quantum annealer system, demonstrating proof of principle. Our initial studies left open the possibility for improvement of D-Wave solutions via judicious choices of system run parameters. Here we report on our investigations for optimizing these system parameters, and how we incorporate machine learning (ML) techniques to further improve on the quality of solutions. In particular, we use the Hamming distance to investigate correlations between various system-run parameters and solution vectors. We then apply a decision tree neural network (NN) to learn these correlations, with the goal of using the neural network to provide further guesses to solution vectors. We successfully implement this NN in a simple integer linear programming (ILP) example, demonstrating how the NN can fully map out the solution space that was not captured by D-Wave. We find, however, for the 3-node network problem the NN is not able to enhance the quality of space of solutions. © 2024, CC BY.

关键词： Machine learning

来源：评论

学校读者我要写书评

暂无评论

Novel Cascaded Incremental Nonlinear Dynamic Inversion Controller Approach for a Tiltrotor VTOL

Novel Cascaded Incremental Nonlinear Dynamic Inversion Contr...

引用

International Conference on Unmanned Aircraft systems (ICUAS)

作者： Mark Henkenjohann Udo Nolte Christian Henke Ansgar Trächtler Scientific Automation Fraunhofer Institute for Mechatronic Systems Design Paderborn Germany Chair for Control Engineering and Mechatronics Paderborn University Heinz Nixdorf Institute Paderborn Germany

This paper presents a novel cascaded incremental nonlinear dynamic inversion (INDI) flight controller approach for a tiltrotor VTOL. The main focus is the adaption of INDI to a specific tiltrotor VTOL configuration aiming for optimal exploitation of the actuator capabilities combined with the advantages of a cascaded INDI. For this purpose the tilt angle of the overall thrust vector with respect to the aircraft is introduced as important connection between two cascaded INDIs: For the outer INDI linearizing translational dynamics this serves as virtual control variable. For the inner INDI linearizing rotational dynamics this variable is a pseudo control input. Thus, the tilt mechanisms of the aircraft can be utilized creating rotational and translational dynamics in a cascaded INDI approach linearizing translational and rotational dynamics separately. The approach is evaluated in simulation studies focusing on functionality, linearization and decoupling.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Monolithically Integrated Two-Stage GaN Gate Drivers

Monolithically Integrated Two-Stage GaN Gate Drivers

引用

Wide Bandgap Power Devices and Applications in Europe (WiPDA Europe), IEEE Workshop on

作者： Michael Basler Richard Reiner Stefan Mönch Daniel Grieshaber Fouad Benkhelifa Rüdiger Quay Fraunhofer Institute for Applied Solid State Physics IAF Freiburg Germany Institute of Electrical Energy Conversion IEW University of Stuttgart Germany Department for Sustainable Systems Engineering INATECH University of Freiburg Germany

ISBN: (数字)9798350362404

ISBN: (纸本)9798350362411

This work presents the design, characterization, and optimization of a monolithically integrated two-stage GaN gate driver. The individually combinable stages provide a high degree of flexibility and can realize different driver topologies. The driver is also optionally manufactured with pad over active layout. Two driver supply concepts can be implemented and evaluated. Dynamic and static on-wafer measurements are shown. Optimization of the driver is performed for various design goals such as power consumption, rise/fall time and delay time. Finally, the results are discussed in detail.

关键词： Voltage measurement Power demand Capacitors Europe Gate drivers Power transistors Delays Topology Gallium nitride Optimization

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：