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Fast OBJ file importing and parsing in CUDA

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Computational Visual Media 2015年第3期1卷 229-238页

作者： Aidan l.Possemiers Ickjai lee James Cook University

Alias – Wavefront OBJ meshes are a common text file type for transferring 3D mesh data between applications made by different ***, as the mesh complexity gets higher and denser, the files become larger and slower to *** paper explores the use of GPUs to accelerate the importing and parsing of OBJ files by studying file read-time, runtime, and load resistance. We propose a new method of reading and parsing that circumvents GPU architecture limitations and improves performance, seeing the new GPU method outperforms CPU methods with a 6×– 8× speedup. When running on a heavily loaded system, the new method only received an 80% performance hit, compared to the160% that the CPU methods received. The loaded GPU speedup compared to unloaded CPU methods was3.5×, and, when compared to loaded CPU methods,8×. These results demonstrate that the time is right for further research into the use of data-parallel GPU acceleration beyond that of computer graphics and high performance computing.

关键词： parsing OBJ vertex buffer object(VBO) general-purpose programming on the graphics processing unit(GPGPU) compute unified device architecture(CUDA)

基于边缘计算的轴向柱塞泵磨损状态辨识方法研究

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机械工程学报 2024年第4期60卷 189-199页

作者：王丹丹黄伟迪张军辉赵守军于斌刘施镐吕飞苏琦徐兵浙江大学流体动力基础件与机电系统全国重点实验室杭州310027 北京精密机电控制设备研究所北京100076 航天伺服驱动与传动技术实验室北京100076

判断轴向柱塞泵的磨损状态对维护轴向柱塞泵正常运行具有重要意义。然而,现有的轴向柱塞泵故障诊断方法大多为离线式和基于云计算的在线式,存在延时长和数据量大的问题,无法满足轴向柱塞泵磨损状态辨识的实时性需求。为了减少延迟时间... 详细信息

判断轴向柱塞泵的磨损状态对维护轴向柱塞泵正常运行具有重要意义。然而,现有的轴向柱塞泵故障诊断方法大多为离线式和基于云计算的在线式,存在延时长和数据量大的问题,无法满足轴向柱塞泵磨损状态辨识的实时性需求。为了减少延迟时间和传输数据量,提出一种基于边缘计算的轴向柱塞泵磨损状态辨识方法。构造出一个集成信号采集、信号预处理、特征提取和磨损状态分类的边缘节点,用于正确和实时地辨识磨损状态。设置4种轴向柱塞泵滑靴副磨损状态作为故障源,并构建相应的磨损故障数据集。为了减少边缘节点计算量,在上位机中利用随机森林包外误差选择敏感特征值。为了实现磨损状态辨识,在上位机中训练磨损状态分类的特征选择人工神经网络模型,并将信号预处理和特征提取功能算法以及模型参数嵌入边缘节点。通过与其他方法的比较和在线磨损状态辨识试验证明所提方法的正确性和实时性。

关键词：轴向柱塞泵边缘计算磨损状态辨识特征敏感程度人工神经网络

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济阳坳陷页岩油储层渗流特征非稳态实验

大庆石油地质与开发 2024年第2期43卷 61-68页

作者：陈挺吕琦孙志刚于春磊王硕桢高云龙中国石化胜利油田分公司勘探开发研究院山东东营257015 中国石化页岩油气勘探开发重点实验室山东东营257015 山东省非常规油气勘探开发重点实验室山东东营257015 中国石化胜利油田博士后科研工作站山东东营257002 中国地质大学(北京)能源学院北京100083

为形成一种适用于济阳坳陷页岩油储层渗流特征参数的高效而且精确的测试方法,基于一维非稳态渗流模型,建立了非稳态页岩油流动实验方法,分析不同裂缝发育情况下页岩的液测渗透率和启动压力梯度。结果表明:非稳态压力恢复法可准确测试页... 详细信息

为形成一种适用于济阳坳陷页岩油储层渗流特征参数的高效而且精确的测试方法,基于一维非稳态渗流模型,建立了非稳态页岩油流动实验方法,分析不同裂缝发育情况下页岩的液测渗透率和启动压力梯度。结果表明:非稳态压力恢复法可准确测试页岩渗透率,测试时间可缩短约90%;由于气液两相间基础物性的巨大差异,液测渗透率约为气测渗透率的0.47%~2.83%;结合数值仿真和压力衰竭测试,可获得页岩液测启动压力梯度(101~102 MPa/m),其随着渗透率的增加呈幂指数递减;层理贯穿缝发育可显著降低页岩的启动压力梯度;相较于稳态法测试,非稳态压力衰竭法测试启动压力梯度数值略小。研究成果可为页岩油储层渗流参数的高效实验测试及开发方案的制定提供技术支撑。

关键词：页岩油非稳态测试渗流特征裂缝发育启动压力梯度济阳坳陷

Extension of emission expectation maximization lookalike algorithms to Bayesian algorithms

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Visual Computing for Industry,Biomedicine,and Art 2019年第1期2卷 119-128页

作者： Gengsheng l.Zeng Ya li Department of Engineering Utah Valley University800 W University ParkwayOremUT 84058USA Department of Radiology and Imaging Sciences University of Utah729 Arapeen DriveSalt Lake CityUT 84108USA Department of Mathematics Utah Valley University800 W University ParkwayOremUT 84058USA

We recently developed a family of image reconstruction algorithms that look like the emission maximum-likelihood expectation-maximization(Ml-EM)*** this study,we extend these algorithms to Bayesian *** family of emission-EM-lookalike algorithms utilizes a multiplicative update *** extension of these algorithms to Bayesian algorithms is achieved by introducing a new simple factor,which contains the Bayesian *** of the extended algorithms can be applied to emission tomography and another to transmission *** simulations are performed and compared with the corresponding un-extended *** total-variation norm is employed as the Bayesian constraint in the computer *** newly developed algorithms demonstrate a stable performance.A simple Bayesian algorithm can be derived for any noise variance *** proposed algorithms have properties such as multiplicative updating,non-negativity,faster convergence rates for bright objects,and ease of *** algorithms are inspired by Green’s one-steplate *** written in additive-update form,Green’s algorithm has a step size determined by the future image value,which is an undesirable feature that our algorithms do not have.

关键词： Image reconstruction Tomography Iterative reconstruction algorithm

Downscaling future climate scenarios to fine scales for hydrologic and ecological modeling and analysis

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Ecological Processes 2012年第1期1卷 109-123页

作者： lorraine E Flint Alan l Flint U.S.Geological Survey Placer Hall6000 J St.SacramentoCA 95819USA

Introduction:Evaluating the environmental impacts of climate change on water resources and biological components of the landscape is an integral part of hydrologic and ecological investigations,and the resultant land and resource management in the twenty-first *** of both climate and simulated hydrologic parameters on ecological processes are relevant at scales that reflect the heterogeneity and complexity of *** present,simulations of climate change available from global climate models[GCMs]require downscaling for hydrologic or ecological ***:Using statistically downscaled future climate projections developed using constructed analogues,a methodology was developed to further downscale the projections spatially using a gradient-inverse-distancesquared approach for application to hydrologic modeling at 270-m spatial ***:This paper illustrates a methodology to downscale and bias-correct national GCMs to subkilometer scales that are applicable to fine-scale environmental *** scenarios were chosen to bracket the range of future emissions put forth by the Intergovernmental Panel on Climate ***-scale applications of downscaled datasets of ecological and hydrologic correlations to variation in climate are ***:The methodology,which includes a sequence of rigorous analyses and calculations,is intended to reduce the addition of uncertainty to the climate data as a result of the downscaling while providing the fine-scale climate information necessary for ecological *** results in new but consistent data sets for the US at 4 km,the southwest US at 270 m,and California at 90 m and illustrates the utility of fine-scale downscaling to analyses of ecological processes influenced by topographic complexity.

关键词： downscaling climate change spatial scale scenarios

Case studies in psychotherapy training using Austria as an example

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World Journal of Clinical Cases 2020年第13期8卷 2787-2801页

作者： Ela Neidhart Henriette löffler-Stastka Department of Psychoanalysis and Psychotherapy and Teaching Center–Postgraduate UnitMedical University of Vienna/General Hospital of ViennaVienna 1090Austria

BACKGROUND Case studies(CS)are relevant for the development of theoretical and practical competencies in *** rapid progress in the development of methods and principles for establishing CS in the last three decades,research into the aims of CS,especially in training,or how CS are to be conducted is *** To elucidate the form and methodology of CS,the objectives of CS used in training institutions(TI),and if/how TIs handle therapist ***,this preliminary investigation will suggest avenues for further research and attempt to establish certain *** In order to counteract researcher bias and enlarge the question-pool,a focus group was *** recorded and transcribed text was analyzed with Mayring’s method of qualitative content analysis,and the generated categories were formulated as *** resulting questionnaire with both qualitative and quantitative queries was sent out(after pre-testing)to all 39 Austrian TIs that provide professional psychotherapy *** answers and text passages received were then also categorized with qualitative content *** analysis was discussed by a peer group consisting of three psychotherapists trained in differing schools of psychotherapeutic *** 94%of Austrian institutes use CS as part of their psychotherapeutic *** of the term“case study”is inconsistent and has a wide variety of *** serve mainly:(1)For observation of training/progress in therapeutic practice and knowledge/acquisition of the theory specific to each psychotherapeutic school;(2)To improve(self-)reflection capabilities;and(3)To expand theoretical *** of the CS written are not accessible for students nor for the research *** than two thirds of the CS take only the position of the author into account(the client’s position is not described).15.5%of the TIs do not consider researcher or therapist allegiance at *** A more pre

关键词： Case study Psychotherapy training Case study research Therapist allegiance Researcher bias

Maternal Environment Effects on Phenolic Defenses in <i>Abutilon theophrasti</i>Seeds

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American Journal of Plant Sciences 2013年第5期4卷 1127-1133页

作者： Brian J. Schutte Sam E. Wortman john l. lindquist Adam S. Davis Department of Agronomy and Horticulture University of Nebraska Lincoln USA Department of Crop Sciences University of Illinois Urbana USA Department of Entomology Plant Pathology & Weed Science New Mexico State University Las Cruces USA United States Department of Agriculture-Agricultural Research Service (USDA-ARS) Global Change and Photosynthesis Research Unit Urbana USA.

A class of phenolic compounds, ortho-dihydroxyphenols (hereafter “o-DHP”), has been implicated with seed survival. Based on expectations of the growth-differentiation balance hypothesis, we predicted that seed o-DHP concentration exhibits a curvilinear response to increasing resource availability in the maternal environment, with maximum o-DHP occurring at moderate resource levels. To test this hypothesis, Abutilon theophrasti seeds were produced under field conditions at two locations. Each location included twelve maternal environments established through factorial combinations of soil compost (+/-), species assemblage (A. theophrasti with and without maize), and soil nitrogen fertilizer (0, 0.5× or 1× local recommendations for maize). Resource availability with respect to A. theophrasti growth was summarized by above-ground biomass at seed harvest (maternal biomass). Results indicated that seed o-DHP concentrations increased then decreased in response to increasing maternal biomass. This relationship was modeled with a unimodal function specific to location (location 1, y = 1.18 + 0.03xe-0.02x, pseudo-R2 = 0.59, p = 0.003;location 2, y = 1.40 + 0.006xe-0.005x;pseudo-R2 = 0.34, p = 0.05). Seed protein concentrations remained constant across maternal biomass levels. Because inherent vulnerability to predation and decay is considered a consequence of chemical protection relative to nutritional offering, our results suggest that A. theophrasti seed susceptibility to lethal attack is influenced by resource levels in the maternal environment. More broadly, our results suggest that the growth-differentiation balance hypothesis can be extended to maternal effects on seed phenolics.

关键词： Environmental Maternal Effect Growth-Differentiation Balance Hypothesis ortho-Dihydroxyphenols Seed Defense Seed Protein

Understanding and managing sanitary risks due to rodent zoonoses in an African city: beyond the Boston Model

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Integrative Zoology 2008年第1期3卷 38-50页

作者： Peter J.TAYlOR lorraine ARNTZEN Mel HAYTER Malcolm IlES john FREAN Steven BElMAIN Durban Natural Science Museum eThekwini Libraries and Heritage DepartmentDurbanSouth Africa National Institute for Communicable Diseases National Health Laboratory ServiceSandringhamSouth Africa City Health:Communicable Diseases eThekwini MunicipalityDurbanSouth Africa Natural Resources Institute Chatham MaritimeKentUK

The Boston Model describes a successful rodent management plan that succeeded in a first-world city in the *** third-world cities, which often contain informal shack settlements, it is debatable whether the Boston Modelwould apply. In Durban, a major harbor city of three million people on the east coast of South Africa, we investigatedthe sanitary risks due to rodents in both formal (residential and commercial) and informal (shacks) sectors,and we evaluated the relative merits of different management interventions suggested by the Boston Model. Bloodand tissue samples of six species (Rattus norvegicus, R. tanezumi, R. rattus, Mus musculus, Mastomys natalensis,Tatera brantsi) from 262 live-trapped rodents from 54 localities were tested for antibodies or DNA for plague (n =193: antibody test), leptospirosis (n = 221 for antibody test;n = 69 for polymerase chain reaction test for DNA) andtoxoplasmosis (n = 217: antibody test). We conducted a socioeconomic survey of 90 household to determine environmentaland socioeconomic disease risk factors in the shack settlement of Cato Crest . No rodents wereseropositive for plague, but nine Norway rats, R. norvegicus (4.1% of the sample tested) were seropositive fortoxoplasmosis, and 22 R. norvegicus (10.0% of sample tested) were seropositive for leptospirosis. Disease endemicareas were concentrated in Cato Crest and the commercial district of Durban. Serology tests of humans living inCato Crest (n = 219) showed 0% exposure to plague, 23% to leptospirosis and 35% to toxoplasmosis. Comparedwith shack-dwellers, the residents of brick houses had slightly lower levels of exposure to leptospirosis andtoxoplasmosis. Based on our results, environmental hygiene and rodent-trapping campaigns were launched in CatoCrest. The initiative owes much of its current success to implementation of the principles inherent in the BostonModel, even though certain elements were lacking.

关键词： Durban leptospirosis plague rodent zoonoses toxoplasmosis.