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用数字电源实现自动补偿

集成电路应用 2011年第9期28卷 20-21页

作者： chris M.young Intersil公司

传统电源需要添加大量元器件进行补偿,但反馈回路和器件复杂性使得补偿非常困难。带有自动补偿功能的数字电源可节省系统开发时间,实现更加稳定的电源,并利用预测诊断提高电源可靠性。

关键词：数字电源自动补偿电源可靠性反馈回路补偿功能元器件复杂性

Ultrasonically actuated neural probes for reduced trauma and inflammation in mouse brain

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Microsystems & Nanoengineering 2022年第6期8卷 137-151页

作者： Po-Cheng Chen Catharine G.young chris B.Schaffer Amit Lal SonicMEMS Laboratory School of Electrical and Computer EngineeringCornell UniversityIthacaNYUSA Meinig School of Biomedical Engineering Cornell UniversityIthacaNYUSA

Electrical neural recordings measured using direct electrical interfaces with neural tissue suffer from a short lifespan because the signal strength decreases over *** inflammatory response to the inserted microprobe can create insulating tissue over the electrical interfaces,reducing the recorded signal below noise *** of the factors contributing to this inflammatory response is the tissue damage caused during probe ***,we explore the use of ultrasonic actuation of the neural probe during insertion to minimize tissue damage in *** neural microprobes were designed and fabricated with integrated electrical recording sites and piezoelectric *** microprobes were actuated at ultrasonic frequencies using integrated piezoelectric *** microprobes were inserted into mouse brains under a glass window over the brain surface to image the tissue surrounding the probe using two-photon *** mechanical force required to penetrate the tissue was reduced by a factor of 2–3 when the microprobe was driven at ultrasonic *** histology at the probe insertion site showed a reduced area of damage and decreased microglia counts with increasing ultrasonic actuation of the *** imaging of the microprobe over weeks demonstrated stabilization of the inflammatory *** of electrical signals from neurons over time suggests that microprobes inserted using ultrasound have a higher signal-tonoise ratio over an extended time period.

关键词： microprobe insertion electrical

No-reference image quality assessment based on AdaBoost_BP neural network in wavelet domain

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Journal of Systems Engineering and Electronics 2019年第2期30卷 223-237页

作者： YAN Junhua BAI Xuehan ZHANG Wanyi XIAO Yongqi CHATWIN chris young Rupert BIRCH Phil College of Astronautics Nanjing University of Aeronautics and Astronautics School of Engineering and Informatics University of Sussex

Considering the relatively poor robustness of quality scores for different types of distortion and the lack of mechanism for determining distortion types, a no-reference image quality assessment(NR-IQA) method based on the Ada Boost BP neural network in the wavelet domain(WABNN) is proposed. A 36-dimensional image feature vector is constructed by extracting natural scene statistics(NSS) features and local information entropy features of the distorted image wavelet sub-band coefficients in three scales. The ABNN classifier is obtained by learning the relationship between image features and distortion types. The ABNN scorer is obtained by learning the relationship between image features and image quality scores. A series of contrast experiments are carried out in the laboratory of image and video engineering(LIVE) database and TID2013 database. Experimental results show the high accuracy of the distinguishing distortion type, the high consistency with subjective scores and the high robustness of the method for distorted images. Experiment results also show the independence of the database and the relatively high operation efficiency of this method.

关键词： image quality assessment (IQA) AdaBoost_BP neural network (ABNN) wavelet transform natural scene statistics (NSS) local information entropy

Efficiency of a Modular Cleanroom for Space Applications

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Fluid Dynamics & Materials Processing 2024年第3期20卷 547-562页

作者： Matthew R.Coburn Charlie young chris Smith Graham Schultz Miguel Robayo Zheng-Tong Xie Faculty of Engineering and Physical Sciences University of SouthamptonSouthamptonSO171BJUK Plastron UK Ltd. Westcott Venture ParkWestcottHP180XBUK Renewable Energy Group University of ExeterExeterTR109FEUK

A prototype cleanroom for hazardous testing and handling of satellites prior to launcher encapsulation,satisfying the ISO8 standard has been designed and analyzed in terms of *** Reynolds Averaged Navier-Stokes(URANS)models have been used to study the related flow field and particulate matter(PM)*** outcomes of the URANS models have been validated through comparison with equivalent large-eddy *** attention has been paid to the location and shape of the air intakes and their orientation in space,in order to balance the PM convection and diffusion inside the *** a cyclone-type flow pattern inside the cleanroom is a key to maintaining a high ventilation efficiency.

关键词： Diffuser LES PM RANS unsteady flow exponential decay

Large shift of the Pacific Walker Circulation across the Cenozoic

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National Science Review 2021年第5期8卷 48-56页

作者： Qing Yan Robert Korty Zhongshi Zhang chris Brierley Xiangyu Li Huijun Wang Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of Sciences Key Laboratory of Meteorological Disaster Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and Technology Department of Atmospheric Sciences Texas A&M UniversityCollege Station Department of Atmospheric Science School of Environmental StudiesChina University of Geosciences NORCE Research Climate Bjerknes Center for Climate Research Department of Geography University College London Climate Change Research Center Chinese Academy of Sciences

Fluctuations in the Pacific Walker Circulation(PWC), a zonally oriented overturning cell across the tropical Pacific, can cause widespread climatic and biogeochemical perturbations. It remains unknown how the PWC developed during the Cenozoic era, with its substantial changes in greenhouse gases and continental positions. Through a suite of coupled model simulations on tectonic timescales, we demonstrate that the PWC was ～38?broader and ～5% more intense during the Early Eocene relative to present. As the climate cooled from the Early Eocene to the Late Miocene, the width of the PWC shrank, accompanied by an increase in intensity that was tied to the enhanced Pacific zonal temperature gradient. However, the locations of the western and eastern branches behave differently from the Early Eocene to the Late Miocene,with the western edge remaining steady with time due to the relatively stable geography of the western tropical Pacific; the eastern edge migrates westward with time as the South American continent moves northwest. A transition occurs in the PWC between the Late Miocene and Late Pliocene, manifested by an eastward shift(both the western and eastern edges migrate eastward by >12?) and weakening(by ～22%),which we show here is linked with the closure of the tropical seaways. Moreover, our results suggest that rising CO2favors a weaker PWC under the same land-sea configurations, a robust feature across the large spread of Cenozoic climates considered here, supporting a weakening of the PWC in a warmer future.

关键词： Pacific Walker Circulation Cenozoic era paleoclimate modeling

Subject-specific Finite Element Modelling of the Human Shoulder Complex Part 1:Model Construction and Quasi-static Abduction Simulation

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Journal of Bionic Engineering 2020年第6期17卷 1224-1238页

作者： Manxu Zheng Zhihui Qian Zhenmin Zou chris Peach Mohammad Akrami Lei Ren School of Mechanical Aerospace and Civil EngineeringUniversity of ManchesterManchesterM139PLUK Key Laboratory of Sensing Technology and Biomedical Instrument of Guangdong province School of Biomedical EngineeringSun Yat-sen UniversityGuangzhou 510006China Key Laboratory of Bionic Engineering Ministry of EducationJilin UniversityChangchun 130022China Shoulder and Elbow Unit The University Hospital of South Manchester NHS Foundation TrustSouthmoor RoadWythenshaweManchester M239LTUK Department of Engineering College of EngineeringMathematicsand Physical SciencesUniversity of ExeterExeter EX44QFUK

Human shoulder joints exhibit stable but highly active characteristics due to a large amount of soft *** Element(FE)modelling plays an important role in enhancing our understanding of the mechanism of shoulder ***,the previous FE shoulder models largely neglected the Three-Dimensional(3D)volume of soft tissues and their sophisticated interactions with the *** study develops a 3D model of the rotator cuff and deltoid muscles and *** also includes cartilage and,for the first time,main ligaments around the joint to provide a better computational representation of the delicate interaction of the soft *** model has potential value for studying the force transfer mechanism and overall joint stability variation caused by 3D pathological changes of rotator cuff *** analysis systems and Magnetic Resonance(MR)scans were used to collect shoulder movement and geometric data from a young healthy subject,*** on MR images,a FE model with detailed representations of the musculoskeletal components was constructed.A multi-body model and the measured motion data were utilised to estimate the loading and boundary ***-static FE analyses simulated four instants of the measured scapular *** determined glenohumeral motion,stress/strain distribution in soft tissues,contact area,and mean/peak contact pressure were found to increase monotonically from 0°to 30°of *** results of muscle forces,bone-on-bone contact force,and superior-inferior movement of the humeral centre during motion were consistent with previous experimental and numerical *** is concluded that the constructed FE shoulder model can accurately estimate the biomechanics in the investigated range of motion and may be further used for the comprehensive study of shoulder musculoskeletal disorders.

关键词： shoulder complex biomechanics finite element glenohumeral joint subject-specific

Prostatic small cell carcinoma with resultant tumor thrombus to the right iliac vein

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Asian Journal of Urology 2024年第4期11卷 666-668页

作者： chris Perez Mark E.Quiring Lendon Hall Katelyn Klimowich young Son Thomas Mueller Gordon Brown Douglas Berkman Touro University California College of Osteopathic MedicineVallejoCAUSA University of North Texas Health Science Center Texas College of Osteopathic MedicineFort WorthTXUSA Jefferson Health New Jersey Department of UrologyStratfordNJUSA

Dear Editor,Prostatic small cell carcinoma(SCC)is a rare,deadly tumor with an overall median survival of fewer than 12 months[[1],[2],[3],[4],[5]].Here we describe a unique case of a patient with prostatic SCC who dev... 详细信息

关键词： thrombus iliac Prostatic

Delayed juvenile behavioral development and prolonged dependence are adaptations to desert life in the grey falcon

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Current Zoology 2022年第6期68卷 679-687页

作者： Jonny SCHOENJAHN chris R.PAVEY Gimme H.WALTER School of Biological Sciences The University of QueenslandBrisbaneQLD 4072Australia CSIRO Land and Water DarwinNT 0822Australia

Rapid learning in the young of most endothermic animals can be expected to be favored by natural selection because early independence reduces the period of *** of comparatively slow juvenile development continue,therefore,to attract scientific *** most species of birds,including raptors,the young depend on their parents for some time after fledging for the provisioning of food and for protection while they learn to become nutritionally and otherwise *** raptors,post-fledging dependence periods that exceed 6 months are exclusive to the largest species and these have reproductive cycles that exceed 12 *** contrast,young of the medium-sized grey falcon Falco hypoleucos have been reported in close company with their parents up to 12 months after fledging,that is,at a time when the adults are expected to breed *** investigated the occurrence and characteristics of prolonged adult–juvenile association relative to other falcons and similar-sized *** found that the behavioral development of grey falcon young is extremely delayed,and that they even depend nutritionally on their parents for up to 12 months after *** suggest that these 2 distinctive features are,ultimately,adaptations of the grey falcon to its extreme environment,Australia’s arid and semi-arid zone,one of the hottest environments in the world.

关键词： arid environment behavioral adaptation bird of prey post-fledging period

Estimation of premature forests in Georgia (USA) using *** Service FIA data and Landsat imagery

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Journal of Forestry Research 2017年第6期28卷 1241-1252页

作者： Hojung Kim chris J. Cieszewski Roger C. Lowe Warnell School of Forestry and Natural Resources University of Georgia 180 E. Green Street AthensGA 30602 USA

We used geographic information system applications and statistical analyses to classify young, premature forest areas in southeastern Georgia using combined data from Landsat TM 5 satellite imagery and ground inventory data. We defined premature stands as forests with trees up to 15 years old. We estimated the premature forest areas using three methods: maximum likelihood classification(MLC), regression analysis, and k-nearest neighbor(k NN)modeling. Overall accuracy(OA) of classifying the premature forest using MLC was 82% and the Kappa coefficient of agreement was 0.63, which was the highest among the methods that we have tested. The k NN approach ranked second in accuracy with OA of 61% and a Kappa coefficient of agreement of 0.22. Regression analysis yielded an OA of 57% and a Kappa coefficient of 0.14. We conclude that Landsat imagery can be effectively used for estimating premature forest areas in combination with image processing classifiers such as MLC.

关键词： Landsat Maximum likelihood classification Regression analysis k-nearest neighbor