检索结果-内蒙古大学图书馆

Numerical study of piezoelectric energy harvester utilizing motorcycle vibrations

AIP Conference Proceedings 2024年第1期3215卷

作者： Mujahid Abdurrahim Radon Dhelika Mohammad Akita Indianto Mechanical Engineering Department Faculty of Engineering Universitas Indonesia Kampus Baru UI Depok Indonesia 16424 Energy Systems Engineering Graduate Program Faculty of Engineering Universitas Indonesia Kampus Baru UI Depok Indonesia 16424 Tropical Renewable Energy Center Faculty of Engineering Universitas Indonesia Kampus Baru UI Depok Indonesia 16424

A numerical study of the piezoelectric energy harvester is performed to see its visibility for application in harvesting motorcycle vibration. The target vibration of 40-70 Hz is the requirement as it is the frequent vibration during motorcycle operations. A composite cantilever structure of SU-8/Al/PVDF/Al is set as the main body of the structure with a thickness of 200/0.3/5/0.3 µm. The length is set as the study point to see the suitable structure for the application. The study found that by designing the correct length, the cantilever’s resonance frequency can match the target vibration frequency; on the other hand longer cantilever results in higher deflection and energy generation of the piezoelectric structure. The study concludes that the length of 33 mm is suitable for covering the 40-70 Hz target vibration with a resonance frequency of 54.3 Hz. The voltage generated is 24.8 mV. This finding is one important step to developing an energy harvester device that can be used in wide applications.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Transferable screened range-separated hybrid functionals for electronic and optical properties of van der Waals materials

arXiv

引用

arXiv 2023年

作者： Camarasa-Gómez, María Ramasubramaniam, Ashwin Neaton, Jeffrey B. Kronik, Leeor Department of Molecular Chemistry and Materials Science Weizmann Institute of Science Rehovoth7610001 Israel Department of Mechanical and Industrial Engineering University of Massachusetts Amherst AmherstMA01003 United States Materials Science and Engineering Graduate Program University of Massachusetts Amherst AmherstMA01003 United States Department of Physics University of California BerkeleyCA94720 United States Materials Sciences Division Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Kavli Energy NanoSciences Institute at Berkeley University of California BerkeleyCA94720 United States

The accurate description of electronic properties and optical absorption spectra is a long-standing challenge for density functional theory. Recently, the introduction of screened range-separated hybrid (SRSH) functionals for solid-state materials has allowed for the calculation of fundamental band gaps and optical absorption spectra that are in very good agreement with many-body perturbation theory. However, since solid-state SRSH functionals are typically tuned to reproduce the properties of bulk phases, their transferability to low-dimensional structures, which experience substantially different screening than in the bulk, remains an open question. In this work, we explore the transferability of SRSH functionals to several prototypical van der Waals materials, including transition-metal sulfides and selenides, indium selenide, black phosphorus, and hexagonal boron nitride. Considering the bulk and a monolayer of these materials as limiting cases, we show that the parameters of the SRSH functional can be determined systematically, using only the band-edge quasiparticle energies of these extremal structural phases as fitting targets. The resulting SRSH functionals can describe both electronic bandstructures and optical absorption spectra with accuracy comparable to more demanding ab initio many-body perturbation theory (GW and Bethe-Salpeter equation) approaches. Selected examples also demonstrate that the SRSH parameters, obtained from the bulk and monolayer reference structures, display good accuracy for bandstructures and optical spectra of bilayers, indicating a degree of transferability that is independent of the fitting procedure. Copyright © 2023, The Authors. All rights reserved.

关键词： Transition metals

来源：评论

学校读者我要写书评

暂无评论

Development of a VS ultrasound diagnostic system with image evaluation functions

Development of a VS ultrasound diagnostic system with image ...

引用

IEEE Global Conference on Consumer Electronics (GCCE)

作者： Jiayi Zhou Norihiro Koizumi Yu Nishiyama Ryosuke Tsumura Hiroyuki Tsukihara Naoki Matsumoto Department of Mechanical and Intelligent Systems The University of Electro-Communications Tokyo Japan Department of Computer and Network Engineering The University of Electro-Communications Tokyo Japan Health and Medical Research Institute National Institute of Advanced Industrial Science and Technology Tokyo Japan Graduate School of Engineering The University of Tokyo Tokyo Japan Department of Gastroenterology and Hepatology Nihon University Tokyo Japan

ISBN: (纸本)9781665492331

An inevitable feature of ultrasound-based diagnoses is that the quality of the ultrasound images produced depends directly on the skill of the physician operating the probe. This is because physicians have to constantly adjust the probe position to obtain a cross-section of the target organ, which is constantly shifting due to patient respiratory motions. Therefore, we developed an ultrasound diagnostic robot that works in cooperation with a visual servo system based on deep learning that will help alleviate the burdens imposed on physicians. Two different image processing methods (BiSeNet V2) were used to detect the target kidney location, as well as to evaluate the appropriateness of the obtained ultrasound images (ResNet 50) in developed system.

关键词： Deep learning Visualization Ultrasonic imaging Image processing Medical services Probes Servomotors

来源：评论

学校读者我要写书评

暂无评论

IoT for Water Quality Categorization

IoT for Water Quality Categorization

引用

International Conference on Cybernetics and Intelligent System (ICORIS)

作者： Hermantoro Sastrohartono Andreas Wahyu Krisdiarto Arief Ika Uktoro Reza Rahutomo Teddy Suparyanto Bens Pardamean Agricultural Engineering Department Faculty of Agricultural Technology Institute of Agriculture STIPER Yogyakarta Indonesia Information System Department School of Information Systems Bina Nusantara University Jakarta Indonesia Bioinformatics & Data Science Research Center Bina Nusantara University Jakarta Indonesia Computer Science Department BINUS Graduate Program Master of Computer Science Bina Nusantara University Jakarta Indonesia

In agricultural water research, the adoption of Internet of Things (IoT) technology has emerged as a pivotal approach for large-scale data collection. Water availability in the context of water quality is very important, both for domestic and industrial purposes. For domestic purposes, drinking water and bathing water are separated. Meanwhile, for the palm oil industry, boiler filler is differentiated from additional process water (dilution water). Water quality parameters can be assessed from turbidity and Total Dissolve Solid (TDS). Measurements using measuring instruments separately and repeatedly require significant energy, time, and costs. This research was conducted with the primary objective of presenting a novel method for categorizing water quality with the approach of IoT sensor technology. The research methodology entailed the utilization of an integrated IoT water sensors system in conjunction with manual water categorization. The methods consist of (1) system design, (2) design and installation of sensor and IoT-based microcontrollers, and (3) accuracy and precision testing compared with laboratory measurements. The precision of the integrated IoT water sensors was assessed through a dedicated sensor precision test, resulting in an accuracy rate of 94.4% for the turbidity sensor and 97.5% for the TDS sensor. Notably, this approach successfully discriminated drinking water with valid categorization, while other water types, including groundwater, water with tea, and water with coffee, yielded null categorization results.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Interface Rotation in Cu/Nb Accumulative Roll Bonded (ARB) Nanolaminates

SSRN

引用

SSRN 2022年

作者： Radchenko, Ihor Zhu, Wenxin Qing, Liu Navarro, Etienne Sahay, Rahul Lee, Pooi See Raghavan, Nagarajan Thomas, Olivier Budiman, Arief Suriadi Chen, Kai State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong University Xi’an China School of Materials Science and Engineering Nanyang Technological University Singapore639798 Singapore Nanyang Technological University Temasek Laboratories@NTU 637553 Singapore Aix Marseille Université Université de Toulon CNRS IM2NP Marseille France Xtreme Mechanics Lab 8 Somapah Road Singapore487372 Singapore Singapore487372 Singapore Department of Manufacturing and Mechanical Engineering and Technology Oregon Institute of Technology Klamath FallsOR97601 United States Industrial Engineering Department BINUS Graduate Program—Master of Industrial Engineering Bina Nusantara University Jakarta11480 Indonesia

Metal-metal nanolaminates made by accumulative roll bonding (ARB) is a developing new class of structural nanocomposites that possesses high strength, good ductility, and can also be produced in bulk. These nanolaminates exhibit strong crystallographic textures and mechanical anisotropy. Yet, their mechanical properties are often measured only along rolling direction (RD). Using in situ pillar compression, we show that in-plane shear deformation mechanism in Cu(63 nm)/Nb(63 nm) ARB nanolaminate strongly depends on the shear direction. Plastic shear along the RD abruptly changes into crystallographic rotation and later into interface shear as the shear direction deviates away from the RD. The observed shear mechanisms are driven by competition between different slip systems in Cu layers and at the interface. We expect similar deformation anisotropy to happen in other ARB nanolaminates with sharp texture and interface orientation. Comprehensive characterization of such nanolaminates may require considering more than just the usual rolling/transverse/normal direction anisotropy. © 2022, The Authors. All rights reserved.

关键词： Anisotropy

来源：评论

学校读者我要写书评

暂无评论

Development of a FES Knee Bending and Stretching Trike System with RISE-based Control and Its Experimental Verification

IEEJ Transactions on Electronics, Information and Systems

引用

IEEJ Transactions on Electronics, Information and systems 2020年第2期140卷 227-234页

作者： Kushima, Yoshihiro Kawai, Hiroyuki Murao, Toshiyuki Kawai, Yasunori Kishitani, Miyako Suzuki, Ryoichi Graduate Program in Mechanical Engineering Kanazawa Institute of Technology 7-1 Ogigaoka Nonoichi Ishikawa924-0838 Japan College of Engineering Kanazawa Institute of Technology 7-1 Ogigaoka Nonoichi Ishikawa924-0838 Japan Department of Electrical Engineering Ishikawa National College of Technology Kitacyujo Tsubata Ishikawa929-0342 Japan Saiseikai Kanazawa Hospital Ni 13-6 Akatsuchimachi Kanazawa Ishikawa929-0353 Japan

The aim of functional electrical stimulation (FES) is restoring a disabled patient’s upper motor neuron by directly applying electrical currents to the paralyzed muscles. This paper considers a FES alternate knee bending and stretching trike system with RISE-based control for rehabilitation. The alternate knee bending and stretching mechanism and a rider with two muscle groups (Quadriceps, Hamstrings) are modeled as an Euler Lagrange system based on knee bending and stretching force direction. A chain and pulley gear mechanism and a linear motion conversion mechanism are loaded on a recumbent trike to keep disabled patient’s motivation for rehabilitation and to use as transportation. The chain and pulley gear mechanism achieves alternate knee bending and stretching motion, and the linear motion conversion mechanism achieves converting linear motion to rotary motion. Experimental results in healthy participants are shown to confirm the validity of the proposed system and the potential of use as transportation. © 2020 The Institute of Electrical Engineers of Japan.

关键词： Neurons

来源：评论

学校读者我要写书评

暂无评论

Social Media Analysis using Sentiment Analysis on COVID-19 from Twitter

Social Media Analysis using Sentiment Analysis on COVID-19 f...

引用

International Conference on Information Technology, Information systems and Electrical engineering (ICITISEE)

作者： Fairuz Iqbal Maulana Yaya Heryadi Lukas Wayan Suparta Yulyani Arifin Computer Science Department BINUS Graduate Program Doctor of Computer Science Bina Nusantara University Jakarta Indonesia Cognitive Engineering Research Group (CERG) Faculty of Engineering Universitas Katolik Indonesia Atma Jaya Jakarta Indonesia Department of Electrical Engineering Faculty of Industrial Technology Institut Teknologi Nasional Yogyakarta Yogyakarta Indonesia Computer Science Department School of Computer Science Bina Nusantara University Jakarta Indonesia

The development of the internet is getting faster, participating in encouraging the emergence of new and innovative information. In filtering the various information that appears, we need a recommended system to perform well for users in today's internet era. A well-performing recommendation system in question is a reliable recommendation algorithm. This algorithm is fundamental to analyzing various information, such as responses on social media based on user behavior data related to the topic of COVID. This data is crawled from tweets on social media Twitter. The data analysis algorithm obtained uses Python, which is then visualized in the form of a diagram. The processed data is user comments on Twitter, and the text data is analyzed using Python, using more than 60000 data sets taken to form visualizations and conclusions. From sentiment analysis, polarity and subjectivity data are obtained to be analyzed, which are negative, neutral, or positive. The result is show positive tweets with 29.2%, negative tweets is 13%, and 57.8% neutral tweets. Lastly, sentiment analysis can help people effectively infer vast and complex data from social media like Twitter.

关键词： COVID-19 Sentiment analysis Analytical models Data analysis Social networking (online) Blogs Data visualization

来源：评论

学校读者我要写书评

暂无评论

On the comparison of three numerical methods applied to building simulation: Finite-differences, RC circuit approximation and a spectral method

引用

建筑模拟（英文版） 2020年第1期13卷 1-18页

作者： Julien Berger Suelen Gasparin Denys Dutykh Nathan Mendes Univ. Grenoble Alpes Univ. Savoie Mont Blanc CNRS LOCIE 73000 Chambéry France Univ. Grenoble Alpes Univ. Savoie Mont Blanc CNRS LAMA 73000 Chambéry France Thermal Systems Laboratory Mechanical Engineering Graduate Program Pontifical Catholic University of Paraná Rua Imaculada Concei??o 1155 CEP : 80215-901 Curitiba - Paraná Brazi

Predictions of physical phenomena in buildings are carried out by using physical models formulated as a mathematical problem and solved by means of numerical methods, aiming at evaluating, for instance, the building thermal or hygrothermal performance by calculating distributions and fluxes of heat and moisture transfer. Therefore, the choice of the numerical method is crucial since it is a compromise among (i) the solution accuracy, (ii) the computational cost to obtain the solution and (iii) the complexity of the method implementation. An efficient numerical method enables to compute an accurate solution with a minimum computational run time (CPU). On that account, this article brings an investigation on the performance of three numerical methods. The first one is the standard and widely used finite-difference approach, while the second one is the so-called RC approach, which is a particular method brought to the building physics area by means of an analogy of electric circuits. The third numerical method is the spectral one, which has been recently proposed to solve nonlinear diffusive problems in building physics. The three methods are evaluated in terms of accuracy on the assessment of the dependent variable (temperature or vapor pressure) or of density of fluxes for three different cases: (i) heat diffusion through a concrete slab, (ii) moisture diffusion through an aerated concrete slab and (iii) heat diffusion using measured temperatures as boundary conditions. Results highlight the spectral approach as the most accurate method. The RC based model with a few number of resistances does not provide accurate results for temperature and vapor pressure distributions neither to flux densities nor conduction loads.

关键词： heat transfer moisture transfer numerical methods finite differences thermal circuit model spectral method

来源：评论

学校读者我要写书评

暂无评论

A Numerical Study of Solar-Pumped Lasers with Multiple Compound Parabolic Concentrators with Length Extension 11th

A Numerical Study of Solar-Pumped Lasers with Multiple Compo...

引用

11th International Symposium on Computational Intelligence and industrial Applications, ISCIIA 2024

作者： Yamada, Ryota Ohkubo, Tomomasa Lou, Haochen Munakata, Hirozumi Matsunaga, Ei-Ichi Sato, Yuji Sustainable Engineering Program Graduate School of Engineering Tokyo University of Technology 1404-1 Katakura Tokyo Hachioji192-0982 Japan Department of Mechanical Engineering Tokyo University of Technology 1404-1 Katakura Tokyo Hachioji192-0982 Japan Joining and Welding Research Institute Osaka University 11-1 Mihogaoka Osaka Ibaraki567-0047 Japan

ISBN: (纸本)9789819647521

In solar-pumped lasers, the conversion efficiency is declining due to the concentration of heat in the laser medium. To solve this problem, a multiple compound parabolic concentrator (MCPC) cavity was proposed to prevent concentration in the previous study. However, extending that cavity length has not been considered. In this study, we investigated the possibility of improving conversion efficiency and dispersing heat by extending the length of the solar cavity and the laser medium. We discussed the absorption density distribution of solar power into the laser medium. As a result, the dispersion of absorption power density of the MCPC cavity was about 40.8–44.7% compared to the Cone type, which is the traditional solar cavity for solar-pumped lasers. Therefore, it is possible to extend the length of both the cavity and the laser medium while maintaining the uniformity effect of the MCPC type of solar cavity, and the conversion efficiency is expected to be improved. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2025.

关键词： Optical pumping

来源：评论

学校读者我要写书评

暂无评论

AI-based Automatic Segmentation of Prostate on Multi-modality Images: A Review

arXiv

引用

arXiv 2024年

作者： Jin, Rui Li, Derun Xiang, Dehui Zhang, Lei Zhou, Hailing Shi, Fei Zhu, Weifang Cai, Jing Peng, Tao Chen, Xinjian School of Future Science and Engineering Soochow University Suzhou China Department of Urology Peking University First Hospital Xicheng District Beijing100034 China MIPAV Lab The School of Electronic and Information Engineering Soochow University Jiangsu China Graduate Program of Medical Physics and Data Science Research Center Duke Kunshan University Jiangsu Kunshan215316 China Department of Mechanical Engineering and Product Design Engineering Swinburne University of Technology Melbourne Australia Department of Health Technology and Informatics The Hong Kong Polytechnic University Hong Kong Department of Radiation Oncology UT Southwestern Medical Center DallasTX United States The State Key Laboratory of Radiation Medicine and Protection Soochow University Jiangsu China

Prostate cancer represents a major threat to health. Early detection is vital in reducing the mortality rate among prostate cancer patients. One approach involves using multi-modality (CT, MRI, US, etc.) computer-aided diagnosis (CAD) systems for the prostate region. However, prostate segmentation is challenging due to imperfections in the images and the prostate’s complex tissue structure. The advent of precision medicine and a significant increase in clinical capacity have spurred the need for various data-driven tasks in the field of medical imaging. Recently, numerous machine learning and data mining tools have been integrated into various medical areas, including image segmentation. This article proposes a new classification method that differentiates supervision types, either in number or kind, during the training phase. Subsequently, we conducted a survey on artificial intelligence (AI)-based automatic prostate segmentation methods, examining the advantages and limitations of each. Additionally, we introduce variants of evaluation metrics for the verification and performance assessment of the segmentation method and summarize the current challenges. Finally, future research directions and development trends are discussed, reflecting the outcomes of our literature survey, suggesting high-precision detection and treatment of prostate cancer as a promising avenue. Impact Statement — Prostate cancer remains a significant health threat, necessitating early detection to reduce mortality rates. Current diagnostic approaches, particularly in medical imaging, face challenges in accurate prostate segmentation due to the organ's complex structure and imaging imperfections. Our review paper delves into AI-based automatic segmentation methods across various imaging modalities (CT, MRI, US), emphasizing their strengths, weaknesses, and the specific challenges they address. By classifying segmentation techniques based on supervision levels, we provide a comprehensive analys

关键词： Computer aided diagnosis

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：