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Phase engineering of Ni-Mn binary layered oxide cathodes for sodiumion batteries
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作者 Feifei Hong Xin Zhou +9 位作者 Xiaohong Liu Guilin Feng Heng Zhang Weifeng Fan Bin Zhang Meihua Zuo Wangyan Xing Ping Zhang Hua Yan Wei Xiang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期501-511,共11页
Nickel-manganese binary layered oxides with high working potential and low cost are potential candidates for sodium-ion batteries,but their electrochemical properties are highly related to compositional diversity.Dive... Nickel-manganese binary layered oxides with high working potential and low cost are potential candidates for sodium-ion batteries,but their electrochemical properties are highly related to compositional diversity.Diverse composite materials with various phase structures of P3,P2/P3,P2,P2/O3,and P2/P3/O3 were synthesized by manipulating the sodium content and calcination conditions,leading to the construction of a synthetic phase diagram for Na_(x)Ni_(0.25)Mn_(0.75)O_(2)(0.45≤x≤1.1).Then,we compared the electrochemical characteristics and structural evolution during the desodiation/sodiation process of P2,P2/P3,P2/03,and P2/P3/O3-Na_(x)Ni_(0.25)Mn_(0.75)O_(2).Among them,P2/P3-Na0.75Ni0.25Mn0.75O2exhibits the best rate capability of 90.9 mA h g^(-1)at 5 C,with an initial discharge capacity of 142.62 mA h g^(-1)at 0.1 C and a capacity retention rate of 78.25%after 100 cycles at 1 C in the voltage range of 2-4.3 V.The observed superior sodium storage performance of P2/P3 hybrids compared to other composite phases can be attributed to the enhanced Na^(+)transfer dynamic,reduction of the Jahn-teller effect,and improved reaction reversibility induced by the synergistic effect of P2 and P3 phases.The systematic research and exploration of phases in Na_(x)Ni_(0.25)Mn_(0.75)O_(2)provide new sights into high-performance nickel-manganese binary layered oxide for sodium-ion batteries. 展开更多
关键词 Phase engineering Ni-Mn layered oxide CATHODE Sodium-ion batteries
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Bidirectional transfer of quantum information for unknown photons via cross-Kerr nonlinearity and photon-number-resolving measurement
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作者 Jino Heo Chang-Ho Hong +1 位作者 Dong-Hoon Lee Hyung-Jin Yang 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第2期82-92,共11页
We propose an arbitrary controlled-unitary(CU) gate and a bidirectional transfer scheme of quantum information(BTQI) for unknown photons.The proposed CU gate utilizes quantum non-demolition photon-number-resolving mea... We propose an arbitrary controlled-unitary(CU) gate and a bidirectional transfer scheme of quantum information(BTQI) for unknown photons.The proposed CU gate utilizes quantum non-demolition photon-number-resolving measurement based on the weak cross-Kerr nonlinearities(XKNLs) and two quantum bus beams;the proposed CU gate consists of consecutive operations of a controlled-path gate and a gathering-path gate.It is almost deterministic and is feasible with current technology when a strong amplitude of the coherent state and weak XKNLs are employed.Compared with the existing optical multi-qubit or controlled gates,which utilize XKNLs and homodyne detectors,the proposed CU gate can increase experimental realization feasibility and enhance robustness against decoherence.According to the CU gate,we present a BTQI scheme in which the two unknown states of photons between two parties(Alice and Bob) are mutually swapped by transferring only a single photon.Consequently,by using the proposed CU gate,it is possible to experimentally implement the BTQI scheme with a certain probability of success. 展开更多
关键词 量子非破坏测量 光子数 克尔非线性 双向传输 量子信息 实验实现 非线性问题 传输方案
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Volunteer Activities in Time of Disaster in Japan's Highly Information-Oriented Society
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作者 Kayoko Yamamoto 《Journal of Earth Science and Engineering》 2013年第3期190-202,共13页
关键词 信息化社会 志愿者 日本 灾害 地震灾区 服务活动 信息系统 信息媒体
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Safety Evaluation Method of Evacuation Routes in Areas in Case of Earthquake Disasters Using Ant Optimization Algorithm and Geographic Information Systems
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作者 Kayoko Yamamoto Ximing Li 《Journal of Environmental Science and Engineering(A)》 2017年第9期462-478,共17页
关键词 安全评估方法 地理信息系统 优化算法 线路 灾难 地震 蚂蚁 阻塞概率
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Parameterization and Explicit Modeling of Cloud Microphysics:Approaches, Challenges, and Future Directions
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作者 Yangang LIU Man-Kong YAU +2 位作者 Shin-ichiro SHIMA Chunsong LU Sisi CHEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第5期747-790,共44页
Cloud microphysical processes occur at the smallest end of scales among cloud-related processes and thus must be parameterized not only in large-scale global circulation models(GCMs)but also in various higher-resoluti... Cloud microphysical processes occur at the smallest end of scales among cloud-related processes and thus must be parameterized not only in large-scale global circulation models(GCMs)but also in various higher-resolution limited-area models such as cloud-resolving models(CRMs)and large-eddy simulation(LES)models.Instead of giving a comprehensive review of existing microphysical parameterizations that have been developed over the years,this study concentrates purposely on several topics that we believe are understudied but hold great potential for further advancing bulk microphysics parameterizations:multi-moment bulk microphysics parameterizations and the role of the spectral shape of hydrometeor size distributions;discrete vs“continuous”representation of hydrometeor types;turbulence-microphysics interactions including turbulent entrainment-mixing processes and stochastic condensation;theoretical foundations for the mathematical expressions used to describe hydrometeor size distributions and hydrometeor morphology;and approaches for developing bulk microphysics parameterizations.Also presented are the spectral bin scheme and particle-based scheme(especially,super-droplet method)for representing explicit microphysics.Their advantages and disadvantages are elucidated for constructing cloud models with detailed microphysics that are essential to developing processes understanding and bulk microphysics parameterizations.Particle-resolved direct numerical simulation(DNS)models are described as an emerging technique to investigate turbulence-microphysics interactions at the most fundamental level by tracking individual particles and resolving the smallest turbulent eddies in turbulent clouds.Outstanding challenges and future research directions are explored as well. 展开更多
关键词 cloud microphysics PARAMETERIZATIONS systems theory bin microphysics particle-based microphysics particleresolved direct numerical simulations
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Interactive Restoration of Three-Dimensional Implicit Surface with Irregular Parts
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作者 Jiayu Ren Yoshihisa Fujita Susumu Nakata 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期2111-2125,共15页
Implicit surface generation based on the interpolation of surface points is one of the well-known modeling methods in the area of computer graphics.Several methods for the implicit surface reconstruction from surface ... Implicit surface generation based on the interpolation of surface points is one of the well-known modeling methods in the area of computer graphics.Several methods for the implicit surface reconstruction from surface points have been proposed on the basis of radial basis functions,a weighted sum of local functions,splines,wavelets,and combinations of them.However,if the surface points contain errors or are sparsely distributed,irregular components,such as curvature-shaped redundant bulges and unexpectedly generated high-frequency components,are commonly seen.This paper presents a framework for restoring irregular components generated on and around surfaces.Users are assumed to specify local masks that cover irregular components and parameters that determine the degree of restoration.The algorithm in this paper removes the defects based on the user-specific masks and parameters.Experiments have shown that the proposed methods can effectively remove redundant protrusions and jaggy noise. 展开更多
关键词 Shape modeling implicit surfaces interactive restoration
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Robust zero-watermarking algorithm based on discrete wavelet transform and daisy descriptors for encrypted medical image
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作者 Yiyi Yuan Jingbing Li +3 位作者 Jing Liu Uzair Aslam Bhatti Zilong Liu Yen-wei Chen 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第1期40-53,共14页
In the intricate network environment,the secure transmission of medical images faces challenges such as information leakage and malicious tampering,significantly impacting the accuracy of disease diagnoses by medical ... In the intricate network environment,the secure transmission of medical images faces challenges such as information leakage and malicious tampering,significantly impacting the accuracy of disease diagnoses by medical professionals.To address this problem,the authors propose a robust feature watermarking algorithm for encrypted medical images based on multi-stage discrete wavelet transform(DWT),Daisy descriptor,and discrete cosine transform(DCT).The algorithm initially encrypts the original medical image through DWT-DCT and Logistic mapping.Subsequently,a 3-stage DWT transformation is applied to the encrypted medical image,with the centre point of the LL3 sub-band within its low-frequency component serving as the sampling point.The Daisy descriptor matrix for this point is then computed.Finally,a DCT transformation is performed on the Daisy descriptor matrix,and the low-frequency portion is processed using the perceptual hashing algorithm to generate a 32-bit binary feature vector for the medical image.This scheme utilises cryptographic knowledge and zero-watermarking technique to embed watermarks without modifying medical images and can extract the watermark from test images without the original image,which meets the basic re-quirements of medical image watermarking.The embedding and extraction of water-marks are accomplished in a mere 0.160 and 0.411s,respectively,with minimal computational overhead.Simulation results demonstrate the robustness of the algorithm against both conventional attacks and geometric attacks,with a notable performance in resisting rotation attacks. 展开更多
关键词 daisy descriptor DCT DWT encryption domain medical image ZERO-WATERMARKING
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Novel Rifle Number Recognition Based on Improved YOLO in Military Environment
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作者 Hyun Kwon Sanghyun Lee 《Computers, Materials & Continua》 SCIE EI 2024年第1期249-263,共15页
Deep neural networks perform well in image recognition,object recognition,pattern analysis,and speech recog-nition.In military applications,deep neural networks can detect equipment and recognize objects.In military e... Deep neural networks perform well in image recognition,object recognition,pattern analysis,and speech recog-nition.In military applications,deep neural networks can detect equipment and recognize objects.In military equipment,it is necessary to detect and recognize rifle management,which is an important piece of equipment,using deep neural networks.There have been no previous studies on the detection of real rifle numbers using real rifle image datasets.In this study,we propose a method for detecting and recognizing rifle numbers when rifle image data are insufficient.The proposed method was designed to improve the recognition rate of a specific dataset using data fusion and transfer learningmethods.In the proposed method,real rifle images and existing digit images are fusedas trainingdata,andthe final layer is transferredto theYolov5 algorithmmodel.The detectionand recognition performance of rifle numbers was improved and analyzed using rifle image and numerical datasets.We used actual rifle image data(K-2 rifle)and numeric image datasets,as an experimental environment.TensorFlow was used as the machine learning library.Experimental results show that the proposed method maintains 84.42% accuracy,73.54% precision,81.81% recall,and 77.46% F1-score in detecting and recognizing rifle numbers.The proposed method is effective in detecting rifle numbers. 展开更多
关键词 Machine learning deep neural network rifle number recognition DETECTION
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IR-YOLO: Real-Time Infrared Vehicle and Pedestrian Detection
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作者 Xiao Luo Hao Zhu Zhenli Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第2期2667-2687,共21页
Road traffic safety can decrease when drivers drive in a low-visibility environment.The application of visual perception technology to detect vehicles and pedestrians in infrared images proves to be an effective means... Road traffic safety can decrease when drivers drive in a low-visibility environment.The application of visual perception technology to detect vehicles and pedestrians in infrared images proves to be an effective means of reducing the risk of accidents.To tackle the challenges posed by the low recognition accuracy and the substan-tial computational burden associated with current infrared pedestrian-vehicle detection methods,an infrared pedestrian-vehicle detection method A proposal is presented,based on an enhanced version of You Only Look Once version 5(YOLOv5).First,A head specifically designed for detecting small targets has been integrated into the model to make full use of shallow feature information to enhance the accuracy in detecting small targets.Second,the Focal Generalized Intersection over Union(GIoU)is employed as an alternative to the original loss function to address issues related to target overlap and category imbalance.Third,the distribution shift convolution optimization feature extraction operator is used to alleviate the computational burden of the model without significantly compromising detection accuracy.The test results of the improved algorithm show that its average accuracy(mAP)reaches 90.1%.Specifically,the Giga Floating Point Operations Per second(GFLOPs)of the improved algorithm is only 9.1.In contrast,the improved algorithms outperformed the other algorithms on similar GFLOPs,such as YOLOv6n(11.9),YOLOv8n(8.7),YOLOv7t(13.2)and YOLOv5s(16.0).The mAPs that are 4.4%,3%,3.5%,and 1.7%greater than those of these algorithms show that the improved algorithm achieves higher accuracy in target detection tasks under similar computational resource overhead.On the other hand,compared with other algorithms such as YOLOv8l(91.1%),YOLOv6l(89.5%),YOLOv7(90.8%),and YOLOv3(90.1%),the improved algorithm needs only 5.5%,2.3%,8.6%,and 2.3%,respectively,of the GFLOPs.The improved algorithm has shown significant advancements in balancing accuracy and computational efficiency,making it promising for practical use in resource-limited scenarios. 展开更多
关键词 Traffic safety infrared image pedestrians and vehicles focal GIoU distributed shift convolution
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Data-driven polarimetric imaging: a review
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作者 Kui Yang Fei Liu +8 位作者 Shiyang Liang Meng Xiang Pingli Han Jinpeng Liu Xue Dong Yi Wei Bingjian Wang Koichi Shimizu Xiaopeng Shao 《Opto-Electronic Science》 2024年第2期1-44,共44页
This study reviews the recent advances in data-driven polarimetric imaging technologies based on a wide range of practical applications.The widespread international research and activity in polarimetric imaging techni... This study reviews the recent advances in data-driven polarimetric imaging technologies based on a wide range of practical applications.The widespread international research and activity in polarimetric imaging techniques demonstrate their broad applications and interest.Polarization information is increasingly incorporated into convolutional neural networks(CNN)as a supplemental feature of objects to improve performance in computer vision task applications.Polarimetric imaging and deep learning can extract abundant information to address various challenges.Therefore,this article briefly reviews recent developments in data-driven polarimetric imaging,including polarimetric descattering,3D imaging,reflection removal,target detection,and biomedical imaging.Furthermore,we synthetically analyze the input,datasets,and loss functions and list the existing datasets and loss functions with an evaluation of their advantages and disadvantages.We also highlight the significance of data-driven polarimetric imaging in future research and development. 展开更多
关键词 deep learning polarimetric imaging image processing
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Method for Evaluating the Location of Tourist-Related Public Facilities Using Genetic Algorithms and GIS 被引量:2
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作者 Mika Inoue Kayoko Yamamoto 《通讯和计算机(中英文版)》 2013年第4期496-512,共17页
关键词 公共设施 区域旅游 评价方法 遗传算法 GIS 位置 观光旅游 地理信息系统
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Investigation of the Behavior of a Jet Issued into Two-Layer Density-Stratified Fluid 被引量:2
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作者 Shogo Shakouchi Shota Fukue Tomomi Uchiyama 《Journal of Flow Control, Measurement & Visualization》 2015年第1期1-9,共9页
This study experimentally investigates a jet flow issued into a two-layer density-stratified fluid in a tank and the resultant mixing phenomena. The upper and lower fluids are water and a NaCl- water solution, respect... This study experimentally investigates a jet flow issued into a two-layer density-stratified fluid in a tank and the resultant mixing phenomena. The upper and lower fluids are water and a NaCl- water solution, respectively, with the lower fluid issued vertically upward from a circular nozzle mounted on the tank bottom. Experimental highlights of the jet behavior and mixing phenomena are classified into three patterns according to the jet Reynolds number and mass concentration of the NaCl-water solution. The internal density current clearly occurs along the density interface, and the maximum jet height is predicted by the Froude number defined by the density difference between the upper and lower fluids. The effect of fluid thickness on the maximum jet height is also clarified. 展开更多
关键词 Density-Stratified Fluid JET MIXING INTERNAL DENSITY Current INTRUSION
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Organogermanium (Ge-132) Suppresses Activities of Stress Enzymes Responsible for Active Oxygen Species in Monkey Liver Preparation 被引量:1
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作者 Takafumi Tezuka Atsunori Higashino +1 位作者 Mitsuo Akiba Takashi Nakamura 《Advances in Enzyme Research》 2017年第2期13-23,共11页
Assays of stress enzymes related to active oxygen species were performed by using an in vitro preparation from the liver of a monkey (Japanese Macaque). Ge-132, an organic germanium compound, viz. poly-trans-[(2-carbo... Assays of stress enzymes related to active oxygen species were performed by using an in vitro preparation from the liver of a monkey (Japanese Macaque). Ge-132, an organic germanium compound, viz. poly-trans-[(2-carboxyethyl) germasesquioxane] [(GeCH2CH2COOH)2O3]n, suppressed the activities of NADH-dependent oxidase and NADPH-dependent oxidase [NAD(P)H-OD] and xanthine oxidase (XOD) as superoxide-forming enzymes, while promoting the activities of superoxide dismutase (SOD) as a superoxide-scavenging enzyme and catalase (CAT) as an enzyme responsible for degradation of hydrogen peroxide (H2O2). The evidence suggests that the levels of active oxygen species such as and H2O2 would be reduced by Ge-132. The possible connection between Ge-132 and activities of stress enzymes is discussed on the basis of these results. 展开更多
关键词 Active Oxygen Species Stress ENZYMES [CAT NAD(P)H-OD SOD XOD] GE-132 [(GeCH2CH2COOH)2O3]n MONKEY LIVER
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GIS as an Information Infrastructure for Recovery and Reconstruction after the Great East Japan Earthquake 被引量:1
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作者 Kayoko Yamamoto 《Journal of Earth Science and Engineering》 2012年第8期461-471,共11页
关键词 地理信息系统 信息基础设施 GIS 大地震 日本 自然灾害 通信技术 数据库建设
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Preliminary study of automatic gastric cancer risk classification from photofluorography 被引量:1
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作者 Ren Togo Kenta Ishihara +7 位作者 Katsuhiro Mabe Harufumi Oizumi Takahiro Ogawa Mototsugu Kato Naoya Sakamoto Shigemi Nakajima Masahiro Asaka Miki Haseyama 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2018年第2期62-70,共9页
AIM To perform automatic gastric cancer risk classificationusing photofluorography for realizing effective mass screening as a preliminary study. METHODS We used data for 2100 subjects including X-ray images, pepsinog... AIM To perform automatic gastric cancer risk classificationusing photofluorography for realizing effective mass screening as a preliminary study. METHODS We used data for 2100 subjects including X-ray images, pepsinogen Ⅰ and Ⅱ levels, PGⅠ/PGⅡ ratio, Helicobacter pylori (H. pylori) antibody, H. pylori eradication history and interview sheets. We performed two-stage classification with our system. In the first stage, H. pylori infection status classification was performed, and H. pylori-infected subjects were automatically detected. In the second stage, we performed atrophic level classification to validate the effectiveness of our system.RESULTS Sensitivity, specificity and Youden index(YI) of H. pylori infection status classification were 0.884, 0.895 and 0.779, respectively, in the first stage. In the second stage, sensitivity, specificity and YI of atrophic level classification for H. pylori-infected subjects were 0.777, 0.824 and 0.601, respectively. CONCLUSION Although further improvements of the system are needed, experimental results indicated the effectiveness of machine learning techniques for estimation of gastric cancer risk. 展开更多
关键词 GASTRIC cancer HELICOBACTER PYLORI Mass SCREENING Photofluorography AUTOMATIC data processing
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Economic Evaluation Method of Photovoltaic Power Generation Installed in Ordinary Homes 被引量:1
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作者 Yasushi Iwasaki Kayoko Yamamoto 《Smart Grid and Renewable Energy》 2014年第6期137-151,共15页
This study aims to develop an economic evaluation method for installing photovoltaic power generation in ordinary homes using GIS (Geographic Information Systems). The conclusions can be summarized in the following th... This study aims to develop an economic evaluation method for installing photovoltaic power generation in ordinary homes using GIS (Geographic Information Systems). The conclusions can be summarized in the following three points: 1) This method determines the profit and loss and payback period in order to evaluate the installation of photovoltaic power generation, taking into account the price of equipment, solar battery module conversion efficiency, subsidy, electricity purchase price, service life and rate for selling electricity. 2) The proposed evaluation method was applied to Kanagawa Prefecture in Japan, providing plural scenarios. Using a solar battery module conversion efficiency of more than 15%, it is possible to make the payback period shorter than the 20-year service life and anticipate a profit in almost the whole area. 3) The areas suitable for photovoltaic power generation are Kawasaki City and Ninomiya-machi. It is necessary to adopt measures to increase the subsidy and install photovoltaic power generating systems in specific places in areas where subsidies are not provided in enough amounts. 展开更多
关键词 PHOTOVOLTAIC Power Generation Economic Evaluation SUBSIDY PROFIT and Loss and Payback PERIOD GIS (Geographic Information Systems)
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Reducing Power and Energy Consumption of Nonvolatile Microcontrollers with Transparent On-Chip Instruction Cache 被引量:1
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作者 Dahoo Kim Itaru Hida +2 位作者 Eric Shun Fukuda Tetsuya Asai Masato Motomura 《Circuits and Systems》 2014年第11期253-264,共12页
Demands for low-energy microcontrollers have been increasing in recent years. Since most microcontrollers achieve user programmability by integrating nonvolatile (NV) memories such as flash memories for storing their ... Demands for low-energy microcontrollers have been increasing in recent years. Since most microcontrollers achieve user programmability by integrating nonvolatile (NV) memories such as flash memories for storing their programs, the large power consumption required in accessing an NV memory has become a major problem. This problem becomes critical when the power supply voltage of NV microcontrollers is decreased. We can solve this problem by introducing an instruction cache, thus reducing the access frequency of the NV memory. Unlike general-purpose microprocessors, microcontrollers used for real-time applications in embedded systems must accurately calculate program execution time prior to its execution. Therefore, we introduce a “transparent” instruction cache, which does not change the existing NV microcontroller’s cycle-level execution time, for reducing power and energy consumption, but not for improving the processing speed. We have conducted detailed microar chitecture design based on the architecture of a major industrial microcontroller, and we evaluated power and energy consumption for several benchmark programs. Our evaluation shows that the proposed instruction cache can successfully reduce energy consumption in a fairly wide range of practical NV microcontroller configurations. 展开更多
关键词 Embedded System MICROCONTROLLER INSTRUCTION Cache NONVOLATILE LOW-POWER Design
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Experimental Study of Flow around a Circular Cylinder inside a Bubble Plume 被引量:2
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作者 Tomomi Uchiyama Yukihiro Ishiguro 《Advances in Chemical Engineering and Science》 2016年第3期269-280,共12页
This study experimentally explores the flow around a cylinder with circular cross-section placed inside a bubble plume. Small gas bubbles with diameter smaller than 0.06 mm are released from electrodes on the bottom o... This study experimentally explores the flow around a cylinder with circular cross-section placed inside a bubble plume. Small gas bubbles with diameter smaller than 0.06 mm are released from electrodes on the bottom of a water tank by electrolysis of water. The bubbles induce water flow around them as they rise because of buoyancy. Inside the generated bubble plume, a cylinder with diameter D of 30 mm is placed at 6.5D above the electrodes. The bubbles and water flow around the cylinder are visualized, and the bubble velocity distribution is measured. The experiments elucidate the bubble behavior around the cylinder, the separated shear layers originating at the cylinder surface, their roll-up, the bubble entrainment in the resultant large-scale eddies behind the cylinder, and the vortex shedding from the cylinder. 展开更多
关键词 Bubble Plume Separated Shear Layer Cylinder Wake Flow Visualization PIV
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Enhancing the Performance of the Marine and Tidal Current Converters Using DC-DC Boost Converter 被引量:1
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作者 Emad M. Ahmed Masahito Shoyama 《Journal of Energy and Power Engineering》 2012年第3期478-484,共7页
关键词 升压转换器 DC-DC 海洋潮汐 电流转换器 性能 转换系统 PWM逆变器 电流速度
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Configuration of propagator method for calculation of electron velocity distribution function in gas under crossed electric and magnetic fields
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作者 Hirotake SUGAWARA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第9期1-18,共18页
This paper presents a self-contained description on the configuration of propagator method(PM)to calculate the electron velocity distribution function(EVDF) of electron swarms in gases under DC electric and magnetic f... This paper presents a self-contained description on the configuration of propagator method(PM)to calculate the electron velocity distribution function(EVDF) of electron swarms in gases under DC electric and magnetic fields crossed at a right angle. Velocity space is divided into cells with respect to three polar coordinates v,θ and f. The number of electrons in each cell is stored in three-dimensional arrays. The changes of electron velocity due to acceleration by the electric and magnetic fields and scattering by gas molecules are treated as intercellular electron transfers on the basis of the Boltzmann equation and are represented using operators called the propagators or Green’s functions. The collision propagator, assuming isotropic scattering, is basically unchanged from conventional PMs performed under electric fields without magnetic fields. On the other hand, the acceleration propagator is customized for rotational acceleration under the action of the Lorentz force. The acceleration propagator specific to the present cell configuration is analytically derived. The mean electron energy and average electron velocity vector in a model gas and SF6 were derived from the EVDF as a demonstration of the PM under the Hall deflection and they were in a fine agreement with those obtained by Monte Carlo simulations. A strategy for fast relaxation is discussed, and extension of the PM for the EVDF under AC electric and DC/AC magnetic fields is outlined as well. 展开更多
关键词 PROPAGATOR method ELECTRON velocity distribution function ELECTRON transport COEFFICIENTS CROSSED electric and magnetic fields MAGNETIZED plasma BOLTZMANN equation
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