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考虑物理特征与行为因素的家庭用能特性建模
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作者 葛少云 李吉峰 +2 位作者 刘洪 王亦然 张鹏 《电力自动化设备》 EI CSCD 北大核心 2019年第3期36-44,共9页
针对常规负荷建模与预测未考虑用户的行为特性,并且需要大量历史数据作为研究基础的问题,提出一种考虑物理特征与行为因素的家庭用能特性建模方法。以家庭能源中心作为研究对象,在介绍总体分析流程的同时,归纳外部需求、内部转换以及终... 针对常规负荷建模与预测未考虑用户的行为特性,并且需要大量历史数据作为研究基础的问题,提出一种考虑物理特征与行为因素的家庭用能特性建模方法。以家庭能源中心作为研究对象,在介绍总体分析流程的同时,归纳外部需求、内部转换以及终端能源负荷类型;考虑物理特征与行为因素,建立电器设备的用能模型,并提出模型扩展方法;在此基础上,通过非侵入式负荷分解与马尔可夫链相结合的方法分析模拟用户的用能行为。算例分析表明,所提方法具有独立刻画负荷肖像曲线的能力,不再依赖大量数据进行派生驱动。 展开更多
关键词 家庭用户 负荷预测 用能细节 马尔可夫链 建模
Assessing the inter-annual variability of separation distances around odour sources to protect the residents from odour annoyance
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作者 Marlon Brancher Martin Piringer +3 位作者 Davide Franco Paulo Belli Filho Henrique De Melo Lisboa Günther Schauberger 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第5期11-24,共14页
In recent years, there has been a growing concern about potential impacts on public health and wellbeing due to exposure to environmental odour. Separation distances between odour-emitting sources and residential area... In recent years, there has been a growing concern about potential impacts on public health and wellbeing due to exposure to environmental odour. Separation distances between odour-emitting sources and residential areas can be calculated using dispersion models, as a means of protecting the neighbourhood from odour annoyance. This study investigates the suitability of using one single year of meteorological input data to calculate reliable direction-dependent separation distances. Accordingly, we assessed and quantified the inter-annual variability of separation distances at two sites with different meteorological conditions, one in Brazil and the other in Austria. A 5-year dataset of hourly meteorological observations was used for each site. Two odour impact criteria set in current regulations were selected to explore their effect on the separation distances. The coefficient of variation was used as a statistical measure to characterise the amount of annual variation. Overall,for all scenarios, the separation distances had a low degree of inter-annual variability(mean coefficient of variation values from 8% to 21%). Reasonable agreements from year to year were therefore observed at the two sites under investigation, showing that one year of meteorological data is a good compromise to achieve reliable accuracy. This finding can provide a more cost-effective solution to calculate separation distances in the vicinity of odour sources. 展开更多
关键词 Environmental odour Odour ANNOYANCE Impact assessment Dispersion modelling REGULATORY criteria SEPARATION distance
强潮环境下小型海岛海滩修复方案数值模拟研究 预览
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作者 张振伟 刘建辉 +1 位作者 李兵 刘贞文 《福建师范大学学报:自然科学版》 CAS 北大核心 2019年第2期22-30,61共10页
应用FVCOM模型对强潮环境小型海岛(平潭大屿岛)周边海域开展了潮汐潮流数值模拟研究,结果表明大屿岛周围潮波为前进波,潮流与潮位变化同步,潮流在高潮(涨急)时由北向南流动,低潮(落急)时由南向北流动,且潮流流速较大.平潭大屿北侧海滩... 应用FVCOM模型对强潮环境小型海岛(平潭大屿岛)周边海域开展了潮汐潮流数值模拟研究,结果表明大屿岛周围潮波为前进波,潮流与潮位变化同步,潮流在高潮(涨急)时由北向南流动,低潮(落急)时由南向北流动,且潮流流速较大.平潭大屿北侧海滩属于典型的岬湾海滩,波浪作用为主要的动力因素,其南侧海滩在波浪和潮汐动力作用下形成的沙滩岸线与海流流向基本平行,潮流起到了一定的作用.针对平潭大屿岛两个沙滩不同的动力特性提出了相应的海滩修复方案,并应用XBEACH模型对强浪作用下海滩剖面演变进行了计算分析. 展开更多
关键词 海滩修复 强潮 波浪 数值模拟 无居民海岛
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基于Simulink的纯电动汽车纵向动力学模型研究 预览
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作者 蔡建红 李守成 金国庆 《机械制造与自动化》 2019年第1期121-123,155共4页
随着现代汽车技术的发展,汽车系统也变得越来越复杂,建模已成为汽车电控系统开发过程中的重要流程。基于小型纯电动汽车平台,建立纯电动仿真模型。因为纯电动汽车与传统燃油汽车的主要差异集中在动力总成上,且其研发目的也更关注经济性... 随着现代汽车技术的发展,汽车系统也变得越来越复杂,建模已成为汽车电控系统开发过程中的重要流程。基于小型纯电动汽车平台,建立纯电动仿真模型。因为纯电动汽车与传统燃油汽车的主要差异集中在动力总成上,且其研发目的也更关注经济性,所以电动车的动力总成匹配、能量管理策略开发等工作也都是基于纵向动力学模型,基于策略模型的搭建并验证了整车性能。 展开更多
关键词 纯电动汽车 建模 纵向动力学 电池 电动机
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从郎之万方程出发建立多孔介质微观模型 预览
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作者 张晓虎 李利峰 韩六平 《科学技术与工程》 北大核心 2019年第6期222-230,共9页
岩土类多孔介质宏观物理力学性质是岩土工程界关注的焦点,其关键是岩土类多孔介质本身复杂的微观结构。综述了当前多孔介质建模的研究现状,简要分析了各种模型建立方法的优势和劣势。针对多孔介质建模的复杂性,从随机动力学相分离过程... 岩土类多孔介质宏观物理力学性质是岩土工程界关注的焦点,其关键是岩土类多孔介质本身复杂的微观结构。综述了当前多孔介质建模的研究现状,简要分析了各种模型建立方法的优势和劣势。针对多孔介质建模的复杂性,从随机动力学相分离过程的朗之万方程出发,将多孔介质的形成过程看作是固相粒子和孔隙相粒子相互作用演化的结果,建立了构造随机多孔介质的微观生长模型。通过不断向空间播撒固相粒子和孔隙相粒子控制多孔介质的演化过程,同时计算了不同参数条件下演化过程中多孔介质孔隙率、欧拉数以及分形维数的变化趋势。由于考虑了固体相和空隙相粒子之间的相互作用力,模型生成的多孔介质与自然界真实的多孔介质更为接近,存在连通和不连通的孔隙结构,孔道迂回曲折。通过与真实样品微观结构的比对,验证了本模型的实用性、可行性。 展开更多
关键词 多孔介质 随机动力学 欧拉数 分形维数 SEM 模型
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Roles of computational modelling in understanding p53 structure, biology, and its therapeutic targeting
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作者 Yaw Sing Tan Yasmina Mhoumadi Chandra S. Verma 《分子细胞生物学报:英文版》 SCIE CAS CSCD 2019年第4期306-316,共11页
The transcription factor p53 plays pivotal roles in numerous biological processes, including the suppression of tumours. The rich availability of biophysical data aimed at understanding its structure–function relatio... The transcription factor p53 plays pivotal roles in numerous biological processes, including the suppression of tumours. The rich availability of biophysical data aimed at understanding its structure–function relationships since the 1990s has enabled the application of a variety of computational modelling techniques towards the establishment of mechanistic models. Together they have provided deep insights into the structure, mechanics, energetics, and dynamics of p53. In parallel, the observation that mutations in p53 or changes in its associated pathways characterize several human cancers has resulted in a race to develop therapeutic modulators of p53, some of which have entered clinical trials. This review describes how computational modelling has played key roles in understanding structural-dynamic aspects of p53, formulating hypotheses about domains that are beyond current experimental investigations, and the development of therapeutic molecules that target the p53 pathway. 展开更多
关键词 P53 STRUCTURE COMPUTATIONAL modelling THERAPEUTIC targeting
基于Stopwatch时间Petri网的柔性作业车间优先级调度研究 预览
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作者 李雅琼 魏绍炎 潘春荣 《现代制造工程》 CSCD 北大核心 2019年第5期29-35,共7页
作业时间不确定的柔性作业车间调度问题由于其计算复杂性、约束条件数量以及工件加工优先级等限制,难以获得最优解。采用Stopwatch时间Petri网对区间柔性作业车间优先级调度问题进行建模,通过Stopwatch状态类可达性分析方法获得模型所... 作业时间不确定的柔性作业车间调度问题由于其计算复杂性、约束条件数量以及工件加工优先级等限制,难以获得最优解。采用Stopwatch时间Petri网对区间柔性作业车间优先级调度问题进行建模,通过Stopwatch状态类可达性分析方法获得模型所有可行变迁触发序列。为了准确执行变迁触发序列的时序分析,采取逆向分步法将此问题转化为线性规划问题,求出最小下界和最小上界的调度路径,进而获得基于优先级的最优调度方案。通过实验结果表明了模型的有效性,为区间柔性作业车间优先级调度提供了有效的模型支持。 展开更多
关键词 柔性作业车间调度 时间PETRI网 建模 时序分析
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Best practices for model-based and simulation-aided engineering of power transmission and motion control systems
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作者 Jean-Charles MARE 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第1期186-199,共14页
This paper deals with the modelling and simulation of aircraft systems, in particular for power transmission and control. It is intended to review, propose and disseminate best practices for making model-based/simulat... This paper deals with the modelling and simulation of aircraft systems, in particular for power transmission and control. It is intended to review, propose and disseminate best practices for making model-based/simulation-aided engineering more efficient at any phase of the system life cycle. The proposals are aimed at creating value, not only by increasing the performance of the product under study but also by shortening the time to market, capitalizing knowledge, mitigating risks and facilitating concurrent engineering. The needs associated with the engineering activities are firstly identified to define a set of requirements for the models. Then, these requirements are used to drive the considerations leading to model development, focusing in particular on the process,modelled physical effects, modelling level, model architecting and concurrent engineering. The third part deals with the model implementation, giving special consideration to the different types of models, causalities, parameterization, implementation and verification. Each part is illustrated by examples related to safety critical actuators. 展开更多
关键词 ACTUATOR Aerospace ARCHITECTURE CAUSALITY MODELLING MOTION control Power transmission Simulation
Economic evaluation of the hepatitis C elimination strategy in Greece in the era of affordable direct-acting antivirals 预览
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作者 Ilias Gountas Vana Sypsa +4 位作者 George Papatheodoridis Kyriakos Souliotis Kostas Athanasakis Homie Razavi Angelos Hatzakis 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第11期1327-1340,共14页
BACKGROUND Hepatitis C virus(HCV) is a leading cause of worldwide liver-related morbidity and mortality. The World Health Organization released an integrated strategy targeting HCV-elimination by 2030. This study aims... BACKGROUND Hepatitis C virus(HCV) is a leading cause of worldwide liver-related morbidity and mortality. The World Health Organization released an integrated strategy targeting HCV-elimination by 2030. This study aims to estimate the required interventions to achieve elimination using updated information for direct-acting antiviral(DAA) treatment coverage, to compute the total costs(including indirect/societal costs) of the strategy and to identify whether the elimination strategy is cost-effective/cost-saving in Greece.AIM To estimate the required interventions and subsequent costs to achieve HCV elimination in Greece.METHODS A previously validated mathematical model was adapted to the Greek HCVinfected population to compare the outcomes of DAA treatment without the additional implementation of awareness or screening campaigns versus an HCV elimination strategy, which includes a sufficient number of treated patients. We estimated the total costs(direct and indirect costs), the disability-adjusted life years and the incremental cost-effectiveness ratio using two different price scenarios.RESULTS Without the implementation of awareness or screening campaigns,approximately 20000 patients would be diagnosed and treated with DAAs by2030. This strategy would result in a 19.6% increase in HCV-related mortality in2030 compared to 2015. To achieve the elimination goal, 90000 patients need to be treated by 2030. Under the elimination scenario, viremic cases would decrease by78.8% in 2030 compared to 2015. The cumulative direct costs to eliminate the disease would range from 2.1-2.3 billion euros(€) by 2030, while the indirect costs would be €1.1 billion. The total elimination cost in Greece would range from €3.2-3.4 billion by 2030. The cost per averted disability-adjusted life year is estimated between €10100 and €13380, indicating that the elimination strategy is very costeffective. Furthermore, HCV elimination strategy would save €560-895 million by2035.CONCLUSION Without large screening programs, eliminati 展开更多
关键词 Hepatitis C ELIMINATION COST effectiveness COST of ELIMINATION Indirect COSTS Projections Mathematical modelling AWARENESS and screening PROGRAMS World Health Organization TARGETS
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3D fracture modelling and limit state analysis of prestressed composite concrete pipes
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作者 Pengfei HE Yang SHEN +1 位作者 Yun GU Pangyong SHEN 《结构与土木工程前沿:英文版》 EI CSCD 2019年第1期165-175,共11页
In this manuscript,we study fracture of prestressed cylindrical concrete pipes.Such concrete pipes play a major role in tunneling and underground engineering.The structure is modelled fully in 3D using three-dimension... In this manuscript,we study fracture of prestressed cylindrical concrete pipes.Such concrete pipes play a major role in tunneling and underground engineering.The structure is modelled fully in 3D using three-dimensional continuum elements for the concrete structure which beam elements are employed to model the reinforcement.This allows the method to capture important phenomena compared to a pure shell model of concrete.A continuous approach to fracture is chosen when concrete is subjected to compressive loading while a combined continuous-discrete fracture method is employed in tension.The model is validated through comparisons with experimental data. 展开更多
关键词 cylindrical CONCRETE structures limit state ANALYSIS 3D fracture modelling PRESTRESSED COMPOSITE pipes reinforced CONCRETE three-point BENDING test
A brief review on key technologies in the battery management system of electric vehicles
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作者 Kailong LIU Kang LI +1 位作者 Qiao PENG Cheng ZHANG 《机械工程前沿:英文版》 CSCD 2019年第1期47-64,共18页
Batteries have been widely applied in many high-power applications,such as electric vehicles(EVs)and hybrid electric vehicles,where a suitable battery management system(BMS)is vital in ensuring safe and reliable opera... Batteries have been widely applied in many high-power applications,such as electric vehicles(EVs)and hybrid electric vehicles,where a suitable battery management system(BMS)is vital in ensuring safe and reliable operation of batteries.This paper aims to give a brief review on several key technologies of BMS,including battery modelling,state estimation and battery charging.First,popular battery types used in EVs are surveyed,followed by the introduction of key technologies used in BMS.Various battery models,including the electric model,thermal model and coupled electro-thermal model are reviewed.Then,battery state estimations for the state of charge,state of health and internal temperature are comprehensively surveyed.Finally,several key and traditional battery charging approaches with associated optimization methods are discussed. 展开更多
关键词 BATTERY management system BATTERY MODELLING BATTERY state ESTIMATION BATTERY CHARGING
Modelling, parameter estimation and assessment of partial shading conditions of photovoltaic modules 预览
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作者 S.LYDEN M.E.HAQUE 《现代电力系统与清洁能源学报(英文)》 CSCD 2019年第1期55-64,共10页
This paper proposes a method for assessing the effect that different features of partial shading conditions(PSC) may have on the operation of a photovoltaic(PV)system.Simulation studies, based on an experimentally val... This paper proposes a method for assessing the effect that different features of partial shading conditions(PSC) may have on the operation of a photovoltaic(PV)system.Simulation studies, based on an experimentally validated model of a PV system, are used to assess the influence of PSC.Three classifications of PSC are defined based on the timescale of their influence on the irradiance experienced by the PV module and the relative location of the voltage at which the global maximum power point occurs is assessed.Sample case studies are presented to illustrate the application of the proposed PSC assessment method.The results have implications for the design of future maximum power point tracking methods. 展开更多
关键词 PHOTOVOLTAIC MODELLING PARTIAL SHADING MAXIMUM power POINT
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Modelling and mapping soil erosion potential in China 预览
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作者 TENG Hong-fen HU Jie +2 位作者 ZHOU Yue ZHOU Lian-qing SHI Zhou 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第2期251-264,共14页
Soil erosion is an important environmental threat in China.However,quantitative estimates of soil erosion in China have rarely been reported in the literature.In this study,soil loss potential in China was estimated b... Soil erosion is an important environmental threat in China.However,quantitative estimates of soil erosion in China have rarely been reported in the literature.In this study,soil loss potential in China was estimated by integrating satellite images,field samples,and ground observations based on the Revised Universal Soil Loss Equation(RUSLE).The rainfall erosivity factor was estimated from merged rainfall data using Collocated CoKriging(ColCOK)and downscaled by geographically weighted regression(GWR).The Random Forest(RF)regression approach was used as a tool for understanding and predicting the relationship between the soil erodibility factor and a set of environment factors.Our results show that the average erosion rate in China is 1.44 t ha–1 yr–1.More than 60%of the territory in China is influenced by soil erosion limitedly,with an average potential erosion rate less than 0.1 t ha–1 yr–1.Other unused land and other forested woodlands showed the highest erosion risk.Our estimates are comparable to those of runoff plot studies.Our results provide a useful tool for soil loss assessments and ecological environment protections. 展开更多
关键词 soil EROSION POTENTIAL RUSLE MAPPING MODELLING
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Effect of vertical stress rest period on deformation behaviour of unbound granular materials:Experimental and numerical investigations 预览
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作者 Ali Alnedawi Kali Prasad Nepal +1 位作者 Riyadh Al-Ameri Mohanad Alabdullah 《岩石力学与岩土工程学报:英文版》 CSCD 2019年第1期172-180,共9页
Repeated load triaxial test is used to assess the deformation behaviour of unbound granular materials(UGMs)in flexible road pavements.Repeated load pulse characteristics(i.e.shape,loading period and rest period)are th... Repeated load triaxial test is used to assess the deformation behaviour of unbound granular materials(UGMs)in flexible road pavements.Repeated load pulse characteristics(i.e.shape,loading period and rest period)are the stress configurations used in the experimental set-up to simulate the passing axle loads.Some researchers and standard testing protocols suggest a rest period of varying durations after a loading phase.A thorough review of existing literature and practises has revealed that there is no agreement about the effect of the rest period of vertical stress pulse on the deformation behaviour of the UGMs.Therefore,the main objective of this study is to investigate the effect of repeated stress rest period on the deformation behaviour of UGMs experimentally.Experiments are conducted,both with and without rest period,using basalt and granite crushed rocks from Victoria,Australia.Furthermore,in order to gain insight into the effect of the rest period,finite element modelling is also developed.Both the experimental and modelling results show that the rest period has a noticeable effect on both resilient and permanent deformation behaviours of UGMs.It is,therefore,recommended to take extra precautions while adopting a particular standard testing protocol and to supplement the results by additional tests with different loading configurations. 展开更多
关键词 Flexible PAVEMENT Unbound GRANULAR materials(UGMs) Repeated load TRIAXIAL test Resilient MODULUS PERMANENT deformation Finite element modelling
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A Survey of Testing for 5G:Solutions,Opportunities,and Challenges 预览
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作者 Ping Zhang Xiaoli Yang +1 位作者 Jianqiao Chen Yuzhen Huang 《中国通信:英文版》 SCIE CSCD 2019年第1期69-85,共17页
With the development of wireless communication technology,the fifth generation mobile communications system(5G)emerges at a historic moment and devotes itself to open the curtain of the information age.Recently,in ord... With the development of wireless communication technology,the fifth generation mobile communications system(5G)emerges at a historic moment and devotes itself to open the curtain of the information age.Recently,in order to satisfy the requirement of different applications,various advanced 5G technologies have been developed in full swing.However,before applying these 5G related technologies in practical systems,effective testing methods are needed to evaluate these technologies in a real,comprehensive,rapid and flexible manner.However,the testing methods are faced with new challenges along with the continuous development of the new 5G technologies.In this paper,we present a survey of 5G testing,including solutions and opportunities.In particular,two cases are considered,i.e.,channel modelling and overthe-air(OTA)testing of antenna systems.Specifically,a non-stationary channel model is proposed to characterize and test massive multiple-input multiple-output(MIMO)channel.In addition,we propose two probe subset selection algorithms for three-dimensional(3D)OTA testing,which minimizes the number of probe antennas while ensuring the accuracy of the target channel emulation.Finally,future research directions and challenges on 5G testing are given. 展开更多
关键词 5G TESTING CHANNEL MODELLING over-the-air TESTING
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Timing of metamorphism and deformation in the Swat valley, northern Pakistan: Insight into garnet-monazite HREE partitioning 预览
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作者 Kyle P. Larson Asghar Ali +3 位作者 Sudip Shrestha Mathieu Soret John M. Cottle Rafique Ahmad 《地学前缘:英文版》 CAS CSCD 2019年第3期849-861,共13页
New metamorphic petrology and geochronology from the Loe Sar dome in the Swat region of northern Pakistan place refined constraints on the pressure, temperature and timing of metamorphism and deformation in that part ... New metamorphic petrology and geochronology from the Loe Sar dome in the Swat region of northern Pakistan place refined constraints on the pressure, temperature and timing of metamorphism and deformation in that part of the Himalayan orogen. Thermodynamic modelling and monazite petrochronology indicate that metamorphism in the area followed a prograde evolution from ~525 ± 25 ℃ and 6 ± 0.5 kbar to ~610 ± 25 ℃ and 9 ± 0.5 kbar, between ca. 39 Ma and 28 Ma. Partitioning of heavy rare earth elements between garnet rims and 30e28 Ma monazite are interpreted to indicate coeval crystallization at peak conditions. Microtextural relationships indicate that garnet rim growth post-dated the development of the main foliation in the area. The regional foliation is folded about large-scale NeS trending fold axes and overprinting EeW trending folds to form km-scale domal culminations. The textural relationships observed indicate that final dome development must be younger than the 30e28 Ma monazite that grew with garnet rims post-regional foliation development, but pre-doming-related deformation. This new timing constraint helps resolve discrepancy between previous interpretations, which have alternately suggested that NeS trending regional folds must be either pre- or post-early Oligocene. Finally, when combined with existing hornblende and white mica cooling ages, these new data indicate that the study area was exhumed rapidly following peak metamorphism. 展开更多
关键词 Pakistan HIMALAYA MONAZITE petrochronology METAMORPHISM Phase EQUILIBRIA modelling Deformation
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Experimental and numerical investigation of mid-infrared laser in Pr3+-doped chalcogenide fiber
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作者 陈华 夏克伦 +4 位作者 刘自军 王训四 章向华 许银生 戴世勋 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第2期257-263,共7页
We report on a chalcogenide glass fiber doped with Pr3+ that can be used for commercialized 1.5-μm and 2-μm laser excitations by emitting broadband 3 μm–5.5 μm fluorescence, which is extruded into a preform and t... We report on a chalcogenide glass fiber doped with Pr3+ that can be used for commercialized 1.5-μm and 2-μm laser excitations by emitting broadband 3 μm–5.5 μm fluorescence, which is extruded into a preform and then drawn into a step-index fiber. The spectroscopic properties of the fiber and glass are reported, and the mid-infrared fiber lasers are also numerically investigated. Cascade lasing is employed to increase the inversion population of the upper laser level. The particle swarm approach is applied to optimize the fiber laser parameters. The output power can reach 1.28 W at 4.89-μm wavelength, with a pump power of 5 W, excitation wavelength at 2.04 μm, Pr3+ ion concentration at 4.22 × 1025 ions/m3,fiber length at 0.94 m, and fiber background loss at 3 dB/m. 展开更多
关键词 MID-INFRARED FIBER LASER CHALCOGENIDE GLASS FIBER rare earth DOPED GLASS FIBER LASER modelling
鸡BCO2基因功能性单核苷酸多态性的生物信息分析 预览
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作者 郝文文 杨倩倩 +4 位作者 张贝 张健 张传生 耿立英 李祥龙 《家禽科学》 2019年第4期17-21,共5页
旨在筛选鸡BCO2基因中具有潜在生物学功能的同义单核苷酸多态性(non-synonymous single nucleotide polymorphisms,nsSNPs)。从SNP数据库中检索出8个BCO2 基因nsSNPs,利用SIFT、PolyPhen-2、PANTHER和PROVEAN方法分析引起的氨基酸替换... 旨在筛选鸡BCO2基因中具有潜在生物学功能的同义单核苷酸多态性(non-synonymous single nucleotide polymorphisms,nsSNPs)。从SNP数据库中检索出8个BCO2 基因nsSNPs,利用SIFT、PolyPhen-2、PANTHER和PROVEAN方法分析引起的氨基酸替换是否可能影响BCO2 的功能预测。进一步对鸡BCO2基因编码的氨基酸序列进行翻译后修饰位点预测以及进化位点保守性预测;使用SWISS-MODEL构建了BCO2野生型以及突变型蛋白质的空间结构。结果表明:3个nsSNPs(rs739117331、rs735703078和rs736211538)可能严重影响BCO2蛋白功能。 展开更多
关键词 BCO2基因 非同义SNP SNP功能预测 蛋白质高级结构构建
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The impact of crustal rheology on natural seismicity:Campi Flegrei caldera case study 预览
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作者 R.Castaldo L.D’Auria +3 位作者 S.Pepe G.Solaro V.De Novellis P.Tizzani 《地学前缘:英文版》 CAS CSCD 2019年第2期453-466,共14页
We analyze the crustal rheology beneath the active resurgent Campi Flegrei caldera(CFc) in Southern Italy by modelling the 3 D brittle-ductile(B/D) transition, based on available thermal, geological and geophysical da... We analyze the crustal rheology beneath the active resurgent Campi Flegrei caldera(CFc) in Southern Italy by modelling the 3 D brittle-ductile(B/D) transition, based on available thermal, geological and geophysical data. Firstly, the thermal field in the conductive physical regime is modeled using a finite element method;based on an optimization tool, this method is applied to evaluate the location and dimensions of the deep thermal source beneath the caldera. A horizontally-extended thermal anomaly located at about 5000 m depth below sea level is identified beneath Pozzuoli Bay, a part of the CFc. The same isotherm is located at a depth of 20,000 m beyond the caldera. This indicates a higher horizontal temperature gradient in the caldera with respect to the surrounding area. Next, we utilize this thermal model to image the 3D rheological stratification of the shallow crust below the caldera with two different values of strain rates. Within the caldera, the B/D transitions with ε equal to 10-12 s-1 and 10-8 s-1 are located at 3000 m and 5000 m depths, respectively. Outside the caldera, the transition is very deep(15,000-20,000 m), seemingly uninfluenced by the thermal state of the CFc volcanism. Finally, we compare these results with the spatial distribution of earthquake hypocenters, Benioff strain release and b-value distribution to investigate the relationship between crustal rheology and seismicity characteristics. Our analysis reveals that the image of the B/D transition is in agreement with the distribution of earthquake hypocenters, constraining the potential seismogenic volume of the region. Our study demonstrates that knowledge of the rheological state of a volcanic system is an important element to interpret its dynamic, forecast future activity and improve evaluation of the associated seismic hazard. 展开更多
关键词 Brittle-ductile transition SEISMICITY CUT-OFF GEOTHERMAL measurements FE CONDUCTIVE thermal MODELLING Campi Flegrei CALDERA
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地质勘查工作流程及国内外质量控制 预览
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作者 李勇 刘宇英 《中国矿山工程》 2019年第2期65-68,共4页
地质勘查主要是运用测绘、地球物理勘探、地球化学探矿、钻探、坑探、浅井、采样测试、地质遥感等地质勘查方法,对一定地区内的岩石、地层构造、矿产、地下水、地貌等地质情况进行的调查研究工作。勘查工作的任一阶段或者环节出现质量... 地质勘查主要是运用测绘、地球物理勘探、地球化学探矿、钻探、坑探、浅井、采样测试、地质遥感等地质勘查方法,对一定地区内的岩石、地层构造、矿产、地下水、地貌等地质情况进行的调查研究工作。勘查工作的任一阶段或者环节出现质量问题都会影响矿产资源量估算以及后续矿业开发。本文主要论述固体矿产资源开发所要进行的勘查工作流程及其质量控制(QAQC)。 展开更多
关键词 地质勘查 钻探 样品加工制备 样品分析 地质建模
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