检索结果-内蒙古大学图书馆

Materials Performance 2020年第9期59卷 50-53页

作者： Aghajani, Abbas Aghajani, Behnaz Subsea R&D Center Isfahan University of Technology Isfahan Iran Department of Civil Engineering Isfahan University of Technology Isfahan Iran

Concrete beams should be resistant against the influence of corrosive agents, environmental degradation, and mechanical forces. For this purpose, the arrangement of reinforcement, concrete mix design, and pole dimensions must be designed to have good durability in field operation. To ensure the quality of concrete poles, laboratory tests and bending tests of the final product are performed. The bend test can determine final quality of the poles. In this article, the effect of two different concrete mixing designs is investigated against the pole’s bend strength behavior. © 2020 NACE International. All rights reserved.

关键词： Concrete mixing

来源：评论

学校读者我要写书评

暂无评论

In-situ detection equipment for radon-in-water:unattended operation and monthly investigations

引用

Acta Oceanologica Sinica 2023年第8期42卷 178-184页

作者： Chunqian Li Meng Li Guangquan Chen Huaming Yu Chenglun Zhang Wen Liu Jinjia Guo Shibin Zhao Lijun Song Xiliang Cui Ying Chai Lu Cao diansheng Ji Bochao Xu Faculty of Information Science and Engineering Ocean University of ChinaQingdao 266100China R&D Center for Marine Instruments and Apparatuses Qingdao Marine Science and Technology CenterQingdao 266200China Key Laboratory of Marine Sedimentology and Environmental Geology First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China Frontiers Science Center for Deep Ocean Multispheres and Earth System/Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education Ocean University of ChinaQingdao 266100China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China Institute of Oceanographic Instrumentation Shandong Provincial Key Laboratory of Ocean Environmental Monitoring Techno1ogyQilu University of Technology(Shandong Academy of Sciences)Qingdao 266061China Yantai Marine Environment Monitoring Central Station of State Oceanic Administration Yantai 264003China

radon is recognized as a powerful tracer of certain geophysical processes in marine and aquatic *** the past few decades,the instruments and methods for measuring radon concentration in water have been developed to some extent but still lack underwater in-situ *** we present an in-situ detection equipment for radon-in-water(pulsed ionization chamber(PIC)-radon)to measure dissolved radon in ocean and groundwater *** equipment has been successfully deployed in the Jiaozhou Bay in July 2022 and has achieved 14 d of unattended underwater in-situ *** it was successfully placed in a groundwater monitoring well in the Laizhou Bay in November 2022 and monitored radon activities for over 30 *** results showed that this instrument had a good indication of submarine groundwater *** PIC-radon detector takes advantage of smaller size,lower power consumption,and is barely influenced by humidity,making it particularly suitable for long-term in-situ measurement,especially in harsh environments with limited human care or deployment spaces.

关键词： radon pulsed ionization chamber(PIC) in-situ measurement membrane groundwater ocean

来源：评论

学校读者我要写书评

暂无评论

Aeroacoustic simulation of broadband sound generated from a cross-flow fan using immersed boundary-lattice Boltzmann method 16

Aeroacoustic simulation of broadband sound generated from a ...

引用

16th Asian International Conference on Fluid Machinery, AICFM 2021

作者： Kusano, K. Furukawa, M. Sakoda, K. Fukui, T. Department of Mechanical Engineering Kyushu University 744 Motooka Nishi-ku Fukuoka819-0395 Japan Advanced Technology R&d Center Mitsubishi Electric Corp. Japan8-1-1 Tsukaguchihonmachi Amagasaki661-8661 Japan

In this study, we investigated the capability of the immersed boundary-lattice Boltzmann method (IB-LBM) in simulating the broadband sound generated from a cross-flow fan. The present method is based on the lattice Boltzmann equation with the d3Q27 particle velocity model, and the cascaded collision operator was used to stably simulate high-reynolds-number flows. Furthermore, the direct-forcing approach was used to consider rotating blades in the regular lattice. To capture turbulence eddies in the rotor, we used a high-resolution grid that contained approximately 340 million nodes. The simulation successfully captured the fundamental flow features of the cross-flow fan such as the eccentric vortex, and the simulation results were consistent with the experimental results in terms of the time-averaged velocity distribution at the outlet of the fan. In addition, by resolving turbulent eddies in the impeller, the simulation successfully predicted the broadband sound spectrum in the frequency range of 2 kHz or less. © Published under licence by IOP Publishing Ltd.

关键词： Fans

来源：评论

学校读者我要写书评

暂无评论

Highly Thermal Conductive Graphene Frameworks Enhanced Paraffin Composite for Thermal Management of Electronics

SSRN

引用

SSrN 2023年

作者： Huang, Wentian Wang, Zhicheng Zhou, Hangjing Yu, Zhiqiang Hao, Zhenliang Gao, Yu Cai, Xiaoming Cai, Jinming Faculty of Materials Science and Engineering Kunming University of Science and Technology Kunming650000 China Graphene Technology R&D Center Guangdong Morion Nanotechnology Co. Ltd Dongguan523069 China

More effective thermal management for current electronic devices is extremely important and challenging than before. Phase change materials (PCMs) based on paraffin wax (PW) is one of promising choices in the field. However, two inevitable obstacles of the poor shape stability and low thermal conductivity severely limit their development and application. In this study, the pure graphene micro-nano pores films (GMNFs) are prepared by common foaming and heat treatment. The GMNFs can provide highly thermal conductivity and stable supporting framework for pure PW to obtain the graphene-based PCMs (GPCMs). The as-prepared GPCM shows high thermal conductivity of 208.08 W·m-1·K-1 and latent heat of 156.97 J·g-1, when the ratio of pure-graphene framework is 20.6 wt%. Moreover, the GPCM shows super stability with negligible mass loss, even when the temperature reaches 147.4 ℃ which is considerably higher than that in the normal operating electronic devices. The performances of GPCMs are easily tunable with reconstructing the GMNFs for different requirements of thermal management. All these contribute GPCMs to show huge potential for the industrial production and the practical applications in electronic devices. © 2023, The Authors. All rights reserved.

关键词： Graphene

来源：评论

学校读者我要写书评

暂无评论

MPC-Based Coordination Control of dual direct-drive Permanent Magnet Motors Used in Coal Mining Belt Conveyors

MPC-Based Coordination Control of Dual Direct-Drive Permanen...

引用

Annual Conference of Industrial Electronics Society

作者： Yaofei Han Chao Gong Shaofeng Chen Zhixun Ma Xing Zhao National Maglev Transportation Engineering R&D Center Tongji University Shanghai China Department of Electrical and Computer Engineering University of Alberta Edmonton Canada School of Physics Engineering and Technology University of York York UK

In the application of coal mining belt conveyors, dual-motor drives based on permanent magnet motors (PMM) are gaining increasing attention now. To achieve high-performance coordination control of the two motors, this paper proposes a finite control set model predictive speed control (FCS-MPSC) method to improve the dynamics and speed tracking performance of the motors. First, the features of the dual-motor drives used in conveyor belts are analyzed. On this basis, the requirements of the control strategies are illustrated. Second, a master-slave control strategy is developed after treating the PMMs at the tail end and head end as the master motor and slave motor, respectively. Third, the FCS-MPSC method is developed for both master and slave motors by using new predicting model. In this process, the issue that the speed property is not directly related to the manipulated variables are tackled. Moreover, in order to further improve the dynamics of the slave motor, a speed reference compensation strategy is proposed. Finally, the proposed FCS-MPSC method is validated through comparative simulation results.

关键词：

来源：评论

学校读者我要写书评

暂无评论

An Advanced Control Strategy for Grid Interfaced dG to Enhance Voltage Support during Unbalanced Faults

An Advanced Control Strategy for Grid Interfaced DG to Enhan...

引用

Sustainable Energy and Future Electric Transportation (SEFET), International Conference on

作者： Suresh Maganti Naveen Yalla N P Padhy Hamad Al Beshr Sajan K Sadanandan Tareg Ghaoud Smart Grid Integration Division DEWA R&D Center Dubai UAE Dept. of Electrical Engineering Indian Institute of Technology (BHU) Varanasi India Director MNIT Jaipur and IIIT Kota Rajasthan India

ISBN: (数字)9798350383997

ISBN: (纸本)9798350384000

Numerous control strategies are proposed to support the grid voltages during asymmetrical faults. Most control strategies are based on sequence-based voltage components for three-phase, three-leg inverter-based distributed Generations(dG). Further, the reactive power injection by these control strategies affects healthy phase voltage, which limits voltage support to avoid over-voltage risk. The Three-phase, Four-leg Inverters(TFI) have recently become more popular due to their ability to supply local loads and zero sequence current control. The voltage support concept is explored less in TFI-based dGs in the case of unbalanced grid faults. In this regard, an advanced control strategy has been developed in this paper to enhance voltage support during asymmetrical grid faults. The proposed control strategy can supply zero-sequence current and reactive power injection into faulty phases without affecting healthy phase voltage magnitude, ensuring safe operating current limits. The proposed voltage support control strategy is suitable for both strong and weak voltage profiles of grids. The proposed control method is validated on a grid-interfaced, three-phase, four-leg inverter-based dG at an operating Short Circuit ratio(SCr) of 3. The performance of the developed voltage support control strategy is validated by comparing the results with those of the conventional control strategy of the same system parameters.

关键词： Current control reactive power Power quality Transportation real-time systems Hardware Circuit faults Voltage control Power generation

来源：评论

学校读者我要写书评

暂无评论

High Temperature Properties of CO2 Gas Mixture with O2 and HFO-1234yf decompositions: Predominant Molecular Products and Critical Electric Field Strength at 300–3000 K

引用

IEEJ Transactions on Power and Energy 2021年第11期141卷 700-711页

作者： Yokomizu, Yasunobu Kodama, Naoto Sugita, Takehiro Ishii, Tatsuya Sato, Motohiro Nakamura, Yasunori Department of Electrical Engineering Nagoya University Furo-cho Chikusa-ku Nagoya464-8603 Japan Advanced Technology R&D Center Mitsubishi Electric Corp. 8-1-1 Tsukaguchi-Honmachi Amagasaki661-8661 Japan

The gases used in high voltage electric power equipment are required to withstand against an externally applied electric field strength. It is therefore essential to find out the electrical insulation strength of the gas. However the high temperature gas formed after the current zero through the arc extinction process in a circuit breaker shows different insulation strengths from that at room temperature, because the high temperature gas consists of various molecular products different from the original gas at room temperature. The CF3CFCH2 (called as HFO-1234yf) at room temperature is known to have a remarkable electrical insulation property similar to SF6. After describing the products generated in CO2 gas mixture with O2 and HFO-1234yf decompositions at temperatures below 3000 K, this paper mentions dielectric breakdown properties of the mixtures in view of the molar fractions of the molecular products. discussions are furthermore made to compare dielectric breakdown properties of CO2 gas and CO2/O2 gas mixture at high temperatures. © 2021 The Institute of Electrical Engineers of Japan.

关键词： Sulfur hexafluoride

来源：评论

学校读者我要写书评

暂无评论

ANALYSIS ANd dESIGN OF SATELLITE CONSTELLATION SPArE STrATEGY USING MArKOV CHAIN

arXiv

引用

arXiv 2024年

作者： Han, Seungyeop Noro, Takumi Ho, Koki Daniel Guggenheim School of Aerospace Engineering Georgia Institute of Technology AtlantaGA30332 United States Advanced Technology R&D Center Mitsubishi Electric Corporation Amagasaki661-8861 Japan Daniel Guggenheim School of Aerospace Engineering Georgia Institute of Technology AtlantaGA30332 United States

This paper introduces the analysis and design method of an optimal spare management policy using Markov chain for a large-scale satellite constellation. We propose an analysis methodology of spare strategy using a multi-echelon (r, q) inventory control model with Markov chain, and review two different spare strategies: direct resupply, which inserts spares directly into the constellation orbit using launch vehicles;and indirect resupply, which places spares into parking orbits before transferring them to the constellation orbit. Furthermore, we propose an optimization formulation utilizing the results of the proposed analysis method, and an optimal solution is found using a genetic algorithm. © 2024, CC BY.

关键词： Markov chains

来源：评论

学校读者我要写书评

暂无评论

Space-filling experimental design for efficient Bayesian optimization

Space-filling experimental design for efficient Bayesian opt...

引用

Joint e-Manufacturing and design Collaboration Symposium (eMdC) & International Symposium on Semiconductor Manufacturing (ISSM)

作者： Shigeru Kinoshita Yuta Inoue Tetsuro Watanabe Kosuke Ikeda Seiwa Nishio Atsushi Teruya Naoki Sakai Takashi Goda Frontier Technology R&D Institute KIOXIA Corporation Yokohama-shi Japan Advanced Memory Development Center KIOXIA Corporation Yokkaichi-shi Japan Graduate School of Engineering The University of Tokyo Bunkyo-ku Japan

ISBN: (数字)9798331510589

ISBN: (纸本)9798331510596

In this study, we propose a space-filling Latin hypercube design with small fill distance and large separation radius based on simulated annealing for efficient Bayesian optimization. Through an example focused on optimizing high aspect ratio hole etching, we demonstrate that initial sampling with the proposed design is advantageous compared to conventional designs in terms of the convergence of Bayesian optimization with fewer experiments.

关键词： Wet etching Atomic layer deposition Simulated annealing Semiconductor device manufacture Hypercubes Bayes methods Optimization Convergence

来源：评论

学校读者我要写书评

暂无评论

determining the optimum economic insulation thickness of double pipes buried in the soil for district heating systems

引用

Frontiers in Energy 2021年第1期15卷 170-185页

作者： Fating LI Pengfei JIE Zhou FANG Zhimei WEN School of Mechanical Engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China Engineering and Technology R&D Center of Clean Air Conditioning in Colleges of Shandong Shandong Huayu University of TechnologyDezhou 253000China

The insulation thickness(IT)of double pipes buried in the soil(dPBIS)for district heating(dH)systems was optimized to minimize the annual total cost of dPBIS for dH *** optimization model to obtain the optimum insulation thickness(OIT)and minimum annual total cost(MATC)of dPBIS for dH systems was *** zero point theorem and fsolve function were used to solve the optimization *** types of heat sources,four operating strategies,three kinds of insulation materials,seven nominal pipe size(NPS)values,and three buried depth(Bd)values were considered in the calculation of the OIT and MATC of dPBIS for dH systems,*** optimization results for the above factors were *** results show that the OIT and MATC of dPBIS for dH systems can be obtained by using the optimization *** analysis was conducted to investigate the impact of some economic parameters,i.e.,unit heating cost,insulation material price,interest rate,and insulation material lifetime,on optimization *** is found out that the impact of sensitivity factors on the OIT and MATC of dPBIS for dH systems is different.

关键词： double pipes optimization model optimum insulation thickness minimum annual total cost

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：