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Heating of nanoparticles and their environment by laser radiation and applications
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作者 Victor K.Pustovalov 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第1期78-115,共38页
This review considers the fundamental dynamic processes involved in the laser heating of metal nanoparticles and their subsequent cooling.Of particular interest are the absorption of laser energy by nanoparticles,the ... This review considers the fundamental dynamic processes involved in the laser heating of metal nanoparticles and their subsequent cooling.Of particular interest are the absorption of laser energy by nanoparticles,the heating of a single nanoparticle or an ensemble thereof,and the dissipation of the energy of nanoparticles due to heat exchange with the environment.The goal is to consider the dependences and values of the temperatures of the nanoparticles and the environment,their time scales,and other parameters that describe these processes.Experimental results and analytical studies on the heating of single metal nanoparticles by laser pulses are discussed,including the laser thresholds for initiating subsequent photothermal processes,how temperature influences the optical properties,and the heating of gold nanoparticles by laser pulses.Experimental studies of the heating of an ensemble of nanoparticles and the results of an analytical study of the heating of an ensemble of nanoparticles and the environment by laser radiation are considered.Nanothermometry methods for nanoparticles under laser heating are considered,including changes in the refractive indices of metals and spectral thermometry of optical scattering of nanoparticles,Raman spectroscopy,the thermal distortion of the refractive index of an environment heated by a nanoparticle,and thermochemical phase transitions in lipid bilayers surrounding a heated nanoparticle.Understanding the sequence of events after radiation absorption and their time scales underlies many applications of nanoparticles.The applicationfields for the laser heating of nanoparticles are reviewed,including thermochemical reactions and selective nanophotothermolysis initiated in the environment by laser-heated nanoparticles,thermal radiation emission by nanoparticles and laser-induced incandescence,electron and ion emission of heated nanoparticles,and optothermal chemical catalysis.Applications of the laser heating of nanoparticles in laser nanomedicine are of particular interest.Significant emphasis is given to the proposed analytical approaches to modeling and calculating the heating processes under the action of a laser pulse on metal nanoparticles,taking into account the temperature dependences of the parameters.The proposed models can be used to estimate the parameters of lasers and nanoparticles in the various applicationfields for the laser heating of nanoparticles. 展开更多
关键词 NANOPARTICLES LASER HEATING modelING Nanothermometry applications
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Evaluations of Chris-Jerry Data Using Generalized Progressive Hybrid Strategy and Its Engineering Applications
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作者 Refah Alotaibi Hoda Rezk Ahmed Elshahhat 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期3073-3103,共31页
A new one-parameter Chris-Jerry distribution,created by mixing exponential and gamma distributions,is discussed in this article in the presence of incomplete lifetime data.We examine a novel generalized progressively ... A new one-parameter Chris-Jerry distribution,created by mixing exponential and gamma distributions,is discussed in this article in the presence of incomplete lifetime data.We examine a novel generalized progressively hybrid censoring technique that ensures the experiment ends at a predefined period when the model of the test participants has a Chris-Jerry(CJ)distribution.When the indicated censored data is present,Bayes and likelihood estimations are used to explore the CJ parameter and reliability indices,including the hazard rate and reliability functions.We acquire the estimated asymptotic and credible confidence intervals of each unknown quantity.Additionally,via the squared-error loss,the Bayes’estimators are obtained using gamma prior.The Bayes estimators cannot be expressed theoretically since the likelihood density is created in a complex manner;nonetheless,Markov-chain Monte Carlo techniques can be used to evaluate them.The effectiveness of the investigated estimations is assessed,and some recommendations are given using Monte Carlo results.Ultimately,an analysis of two engineering applications,such as mechanical equipment and ball bearing data sets,shows the applicability of the proposed approaches that may be used in real-world settings. 展开更多
关键词 Chris-Jerry model generalized censoring likelihood and Bayes estimations MCMC algorithms engineering applications
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Functional Sustainability of a Flight Dynamics Control System for Stable Hovering Flight of an Unmanned Aerial Vehicle(UAV),such as in Agricultural Applications:Mathematical Modeling and Simulation
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作者 Naji Mordi Naji Al-Dosary 《Journal of Agricultural Science and Technology(A)》 2023年第1期1-29,共29页
The simulation of a control system for the longitudinal axis of the rotary or fixed-wing unmanned aerial vehicles(UAVs)is demonstrated in this study.The control unit includes design considerations of two controllers t... The simulation of a control system for the longitudinal axis of the rotary or fixed-wing unmanned aerial vehicles(UAVs)is demonstrated in this study.The control unit includes design considerations of two controllers to provide robust stability,tracking of the proposed linear dynamics,an adequate set of proportional-integral-derivative(PID)controller gains,and a minimal cost function.The PID control and linear quadratic regulator(LQR)with or without full-state-observer were evaluated.An optimal control system is assumed to provide fast rise and settling time,minimize overshoot,and eliminate the steady-state error.The effectiveness of this approach was verified by a linear model of the UAV aircraft in the semi-dynamic simulation platform of Matlab/Simulink,in which the open-loop system was assessed in terms of flight robustness and reference tracking.The experimental results show that the proposed controllers effectively improve the configuration of the control system of the plant,maintain the sustainability of the dynamic flight model stability,and diminish the flight controller errors.The LQR provides robust stability,but it is not optimal in the transient phase of particular plant output.The PID control system can adjust the controller’s gains for optimal hovering(or stable slow flight)and is especially useful for the tracking system.Finally,comparing aircraft stability using PID and LQR controllers shows that the latter has less overshoot and a shorter settling time;in addition,all proposed controllers can be practically deployed as one UAV’s system,which can be handled as an exemplary model of the UAV flight management system. 展开更多
关键词 Agricultural applications cost function dynamic model PID&LQR controllers steady-state error UAV aircraft
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Development,modeling and application of piezoelectric fiber composites 被引量:13
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作者 林秀娟 周科朝 +1 位作者 张晓泳 张斗 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第1期98-107,共10页
Piezoelectric materials are capable of actuation and sensing and have been used in a wide variety of smart devices and structures.Active fiber composite and macro fiber composite are newly developed types of piezoelec... Piezoelectric materials are capable of actuation and sensing and have been used in a wide variety of smart devices and structures.Active fiber composite and macro fiber composite are newly developed types of piezoelectric composites,and show superior properties to monolithic piezoelectric wafer due to their distinctive structures.Numerous work has focused on the performance prediction of the composites by evaluation of structural parameters and properties of the constituent materials with analytical and numerical methods.Various applications have been explored for the piezoelectric fiber composites,including vibration and noise control,health monitoring,morphing of structures and energy harvesting,in which the composites play key role and demonstrate the necessity for further development. 展开更多
关键词 PIEZOELECTRIC active fiber composite macro fiber composite modelING smart applications
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Process model of IT impacts on firm competitiveness based on application capability of information technology 被引量:4
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作者 王念新 仲伟俊 梅姝娥 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期114-118,共5页
To investigate the process of information technology (IT) impacts on firm competitiveness, an integrated process model of IT impacts on firm competitiveness is brought forward based on the process-oriented view, the... To investigate the process of information technology (IT) impacts on firm competitiveness, an integrated process model of IT impacts on firm competitiveness is brought forward based on the process-oriented view, the resource-based view and the complementary resource view, which is comprised of an IT conversion process, an information system (IS) adoption process, an IS use process and a competition process. The application capability of IT plays the critical role, which determines the efficiency and effectiveness of the aforementioned four processes. The process model of IT impacts on firm competitiveness can also be used to explain why, under what situations and how IT can generate positive organizational outcomes, as well as theoretical bases for further empirical study. 展开更多
关键词 application capability of IT IT business value process-oriented view process model
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The Application of ARIMA Model in Forecasting of PDSI in Henan Province
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作者 厉玉昇 《Agricultural Science & Technology》 CAS 2016年第3期760-764,共5页
[Objective] The aim was to establish drought forecasting model with high precision. [Method] With an ARIMA regression model, the research performed Palmer Drought mode(PDSI) time series modeling analysis of Henan Pr... [Objective] The aim was to establish drought forecasting model with high precision. [Method] With an ARIMA regression model, the research performed Palmer Drought mode(PDSI) time series modeling analysis of Henan Province based on PDSI time series and DPS(Data Processing Software) in order to build drought forecasting model. [Result] It is feasible to perform drought forecasting with appropriate parameters. [Conclusion] ARIMA model is practical and more precise in PDSI-based drought analysis and forecasting. 展开更多
关键词 ARIMA model PDSI Forecasting application Henan Province
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对《Plant Growth Modeling and Applications》一书的评介
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作者 熊范伦 《自动化学报》 EI CSCD 北大核心 2004年第3期F002-F002,共1页
农业信息技术能够快速完成农业科技、市场和政府等信息的传输和利用,加速科研成果的形成、规范、集成,缩短转化周期,科学指导和管理生产,从而改变传统农业高度分散、生产规模小、时空变异大、规模化程度差、稳定性和可控程度低等行业性... 农业信息技术能够快速完成农业科技、市场和政府等信息的传输和利用,加速科研成果的形成、规范、集成,缩短转化周期,科学指导和管理生产,从而改变传统农业高度分散、生产规模小、时空变异大、规模化程度差、稳定性和可控程度低等行业性弱点,提高农业生产者和管理者的素质和能力.农业信息化近些年来在我国有了快速的发展.2003年12月10日,我国科技部863计划支持的重大专项"智能化农业信息技术应用示范工程"(俗称"电脑农业")荣获世界信息峰会全球大奖,标志着中国在农业专家系统和智能化农业信息技术应用方面取得了重大成就. 展开更多
关键词 《Plant GROWTH modeling and applications》 农业信息技术 书评 “电脑农业” 中国 智能化农业信息技术
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Analysis on Application of Pragmatic Translation Skill Structure Model in Translation Teaching
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作者 宋俐娟 《疯狂英语(理论版)》 2016年第3期155-156,共2页
As the core content of pragmatic translation teaching research,pragmatic translation skill is closely correlated with translation technique and operation field.Viewed from the current English teaching situation in col... As the core content of pragmatic translation teaching research,pragmatic translation skill is closely correlated with translation technique and operation field.Viewed from the current English teaching situation in colleges and universities,translation skill is not cultivated as an independent language competence.Moreover,its research is insufficient.On account of this,the author first gives an introduction to pragmatic translation skill and pragmatic translation skill structure model in this paper.On this basis,the author also analyzes the application of pragmatic translation skill structure model in translation teaching. 展开更多
关键词 pragmatic translation skill structure model translation teaching application
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AIGC Scenario Analysis and Research on Technology Roadmap of Internet Industry Application 被引量:2
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作者 Xiongfei Ren Lili Tong +1 位作者 Jia Zeng Chen Zhang 《China Communications》 SCIE CSCD 2023年第10期292-304,共13页
The explosion of ChatGPT is considered to be a milestone in the normalization of artificial intelligence education applications.On the technical line,the cross-modal AI generation application based on human feedback s... The explosion of ChatGPT is considered to be a milestone in the normalization of artificial intelligence education applications.On the technical line,the cross-modal AI generation application based on human feedback system is accelerated.In the business model,the scenes to realize interactive functions are constantly enriched.This paper reviews the evolution process of AIGC,closely follows the current situation of the coexistence of business acceleration and technical worries in the application of artificial intelligence education,analyzes the application of AIGC education in 7 subdivided fields,and analyzes the optimization direction of application cases from the perspective of perception-cognition-creation technology maturity matrix.The 3 recommendations and 2 follow-up research directions will promote the scientific application of artificial intelligence education in the AIGC period. 展开更多
关键词 AIGC artificial intelligence education application large model
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Nutrient Application Model Affects the Contents of Chlorophyll and Carotenoid in Functional Leaves of Early Rice
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作者 周升明 周旋 +5 位作者 陈雄鹰 彭建伟 蔡桂青 刘强 荣湘民 黄维 《Agricultural Science & Technology》 CAS 2013年第11期1603-1609,共7页
The objective of this study was to investigate the effects of different nutri-ent application models on the contents of chlorophyl and carotenoid in the functional leaves of early rice. Using rice cultivar Xiangzaoxia... The objective of this study was to investigate the effects of different nutri-ent application models on the contents of chlorophyl and carotenoid in the functional leaves of early rice. Using rice cultivar Xiangzaoxian45 as experimental materials, the experiment was performed by designing 6 treatments, i.e., T1 (fertilization without nitrogen), T2(local conventional fertilization), T3(fertilization for high yield and high effi-ciency), T4 (fertilization for super high yield), T5 (fertilization application for super high yield and high efficiency A) and T6 (fertilization application for super high yield and high efficiency B) in two experimental plots Yiyang and Xiangyin. The results showed that T3 respectively increased the contents of chlorophyl and carotenoid at fil ing stage by 29.27%, 38.20% and 13.16%, 30.12% in Yiyang and Xiangyin, as wel as yield of early rice by 4.20%, 4.80% to T2 on the condition of saving 20% ni-trogen fertilizer. Additional y, T5 and T6 on the condition of saving 16.7% nitrogen fertilizer by T4 increased the contents of chlorophyl and carotenoid of fil ing stage by 53.91%, 53.73% and 35.95%, 37.47% in Yiyang and Xiangyin, as wel as yield of early rice by 16.60%, 18.75% to T2 in Yiyang; increased the contents of chlorophyl and carotenoid at fil ing stage by 57.82%, 56.80% and 54.88%, 57.03% in Yiyang and Xiangyin, as wel as yield of early rice 10.10%, 6.75% to T2 in Xiangyin. More-over, there was a significant correlation or an extremely significant correlation be-tween yield and the contents of chlorophyl and carotenoid at different soil fertility level (P〈0.05 or P〈0.01). Therefore, nutrient application plays an important role in the contents of chlorophyl and carotenoid in the functional leaves of early rice. 展开更多
关键词 Early rice Nutrient application model Chlorophyll content Carotenoidcontent Dynamic change
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Model Checking-Based Testing of Web Applications 被引量:2
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作者 ZENG Hongwei MIAO Huaikou 《Wuhan University Journal of Natural Sciences》 CAS 2007年第5期922-926,共5页
A formal model representing the navigation behavior of a Web application as the Kripke structure is proposed and an approach that applies model checking to test case generation is presented. The Object Relation Diagra... A formal model representing the navigation behavior of a Web application as the Kripke structure is proposed and an approach that applies model checking to test case generation is presented. The Object Relation Diagram as the object model is employed to describe the object structure of a Web application design and can be translated into the behavior model. A key problem of model checking-based test generation for a Web application is how to construct a set of trap properties that intend to cause the violations of model checking against the behavior model and output of counterexamples used to construct the test sequences. We give an algorithm that derives trap properties from the object model with respect to node and edge coverage criteria. 展开更多
关键词 Web application test generation model checking consistency relation
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Ferroelectricity of hafnium oxide-based materials:Current status and future prospects from physical mechanisms to device applications
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作者 Wanwang Yang Chenxi Yu +9 位作者 Haolin Li Mengqi Fan Xujin Song Haili Ma Zheng Zhou Pengying Chang Peng Huang Fei Liu Xiaoyan Liu Jinfeng Kang 《Journal of Semiconductors》 EI CAS CSCD 2023年第5期78-121,共44页
The finding of the robust ferroelectricity in HfO_(2)-based thin films is fantastic from the view point of both the fundamentals and the applications.In this review article,the current research status of the future pr... The finding of the robust ferroelectricity in HfO_(2)-based thin films is fantastic from the view point of both the fundamentals and the applications.In this review article,the current research status of the future prospects for the ferroelectric HfO_(2)-based thin films and devices are presented from fundamentals to applications.The related issues are discussed,which include:1)The ferroelectric characteristics observed in HfO_(2)-based films and devices associated with the factors of dopant,strain,interface,thickness,defect,fabrication condition,and more;2)physical understanding on the observed ferroelectric behaviors by the density functional theory(DFT)-based theory calculations;3)the characterizations of microscopic and macroscopic features by transmission electron microscopes-based and electrical properties-based techniques;4)modeling and simulations,5)the performance optimizations,and 6)the applications of some ferroelectric-based devices such as ferroelectric random access memory,ferroelectric-based field effect transistors,and the ferroelectric tunnel junction for the novel information processing systems. 展开更多
关键词 FERROELECTRICITY HfO_(2)-based thin films physical mechanism characterization modeling and simulation applications
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Local icariin application enhanced periodontal tissue regeneration and relieved local inflammation in a minipig model of periodontitis 被引量:9
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作者 Xiuli Zhang Nannan Han +4 位作者 Guoqing Li Haoqing Yang Yangyang Cao Zhipeng Fan Fengqiu Zhang 《International Journal of Oral Science》 SCIE CAS CSCD 2018年第3期168-173,共6页
Periodontitis is an inflammatory autoimmune disease. Treatment should alleviate inflammation, regulate the immune reaction and promote periodontal tissue regeneration. Icariin is the main active ingredient of Epimedii... Periodontitis is an inflammatory autoimmune disease. Treatment should alleviate inflammation, regulate the immune reaction and promote periodontal tissue regeneration. Icariin is the main active ingredient of Epimedii Folium, and it is a promising compound for the enhancement of mesenchymal stem cell function, promotion of bone formation, inhibition of bone resorption, alleviation of inflammation and regulation of immunity. The study investigated the effect of icariin on periodontal tissue regeneration in a minipig model of periodontitis. The minipig model of periodontitis was established. Icariin was injected locally. The periodontal clinical assessment index, a computed tomography(CT) scan, histopathology and enzyme-linked immune sorbent assay(ELISA)were used to evaluate the effects of icariin. Quantitative analysis results 12 weeks post-injection demonstrated that probing depth,gingival recession, attachment loss and alveolar bone regeneration values were(3.72 ± 1.18) mm vs.(6.56 ± 1.47) mm,(1.67 ± 0.59)mm vs.(2.38 ± 0.61) mm,(5.56 ± 1.29) mm vs.(8.61 ± 1.72) mm, and(25.65 ± 5.13) mm3 vs.(9.48 ± 1.78) mm3 in the icariin group and0.9% NaCl group, respectively. The clinical assessment, CT scan, and histopathology results demonstrated significant enhancement of periodontal tissue regeneration in the icariin group compared to the 0.9% NaCl group. The ELISA results suggested that the concentration of interleukin-1 beta(IL-1β) in the icariin group was downregulated compared to the 0.9% NaCl group, which indicates that local injection of icariin relieved local inflammation in a minipig model of periodontitis. Local injection of icariin promoted periodontal tissue regeneration and exerted anti-inflammatory and immunomodulatory function. These results support the application of icariin for the clinical treatment of periodontitis. 展开更多
关键词 Local icariin application enhanced periodontal tissue regeneration and relieved local inflammation in a minipig model of periodontitis ELISA
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Modeling of Microstructure Evolution and Mechanical Properties of Steel Plates Produced by Thermo-Mechanical Control Process and Its On-line Application 被引量:1
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作者 Yunbo XU, Yongmei YU, Xianghua LIU and Guodong WANGState Key Laboratory of Rolling Technology and Automation, Northeastern University, P.O. Box 105, Shenyang 110004, ChinaPh.D., 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第1期13-16,共4页
An integrated metallurgical model was developed to predict microstructure evolution and mechanical properties of low-carbon steel plates produced by TMCP. The metallurgical phenomena occurring during TMCP and mechanic... An integrated metallurgical model was developed to predict microstructure evolution and mechanical properties of low-carbon steel plates produced by TMCP. The metallurgical phenomena occurring during TMCP and mechanical properties were predicted for different process parameters. In the later passes full recrystallization becomes difficult to occur and higher residual strain remains in austenite after rolling. For the reasonable temperature and cooling schedule, yield strength of 30 mm plain carbon steel plate can reach 310 MPa. The first on-line application of prediction and control of microstructure and properties (PCMP) in the medium plate production was achieved. The predictions of the system are in good agreement with measurements. 展开更多
关键词 Thermo-mechanical control process Metallurgical model Low-carbon steel Prediction and control of microstructure and properties On-line application
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IOT technology application model research of transportation industry in China 被引量:3
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作者 Lai Mingyong Zhou Tang Liu Zhengchi 《Engineering Sciences》 EI 2013年第3期90-96,共7页
The paper studied the connection between internet of things (lOT) technology and transportation industry. Meanwhile, the definition of IOT in transportation was given. Concerning that many problems occurred during t... The paper studied the connection between internet of things (lOT) technology and transportation industry. Meanwhile, the definition of IOT in transportation was given. Concerning that many problems occurred during the process of traditional intelligent transportation system, the paper proposed a promising model of lOT in transportation. The advantage of the information utilization model from information to function was confirmed through comparative study. Finally, the model presented that a real interconnection of transportation would be achieved based on the unified information collection. It can greatly save cost on technology transfer, exploit potential value of information, and promote the emergence of a sustainable information service market and the industrial upgrade. 展开更多
关键词 IOT intelligent transportation system sensor network IOT in transportation application model
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Advances in Application of Models in Soil Quality Evaluation 被引量:1
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作者 SI Zhi-guo WANG Ji-jie +3 位作者 YU Yuan-chun LIANG Guan-feng CHEN Chang-ren SHU Hong-lan 《Asian Agricultural Research》 2012年第11期89-93,共5页
Soil quality is a comprehensive reflection of soil properties.Since the soil quality concept was put forward in the 1970s,the quality of different type soils in different regions have been evaluated through a variety ... Soil quality is a comprehensive reflection of soil properties.Since the soil quality concept was put forward in the 1970s,the quality of different type soils in different regions have been evaluated through a variety of evaluation methods,but it still lacks universal soil quantity evaluation models and methods.In this paper,the applications and prospects of grey relevancy comprehensive evaluation model,attribute hierarchical model,fuzzy comprehensive evaluation model,matter-element model,RAGA-based PPC /PPE model and GIS model in soil quality evaluation are reviewed. 展开更多
关键词 SOIL QUALITY EVALUATION model application
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A Novel Lifecycle Model for Web-based Application Development in Small and Medium Enterprises 被引量:1
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作者 Wei Huang Ru Li +3 位作者 Carsten Maple Hong-Ji Yang David Foskett Vince Cleaver 《International Journal of Automation and computing》 EI 2010年第3期389-398,共10页
Software engineering's lifecycle models havc proven to be very important for traditional software development. However, can these models be applied to the development of Web-based applications as well? In recent yea... Software engineering's lifecycle models havc proven to be very important for traditional software development. However, can these models be applied to the development of Web-based applications as well? In recent years, Web-based applications have become more and more complicated and a lot of efforts have been placed on introducing new technologies such as J2EE, PhP, and .NET, etc., which have been universally accepted as the development technologies for Web-based applications. However, there is no universally accepted process model for the development of Web-based applications. Moreover, shaping the process model for small medium-sized enterprises (SMEs), which have limited resources, has been relatively neglected. Based on our previous work, this paper presents an expanded lifecycle process model for the development of Web-based applications in SMEs. It consists of three sets of processes, i.e., requirement processes, development processes, and evolution processes. Particularly, the post-delivery evolution processes are important to SMEs to develop and maintain quality web applications with limited resources and time. 展开更多
关键词 WEB development of Web-based applications lifecycle models small medium-sized enterprises (SMEs).
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Application of Pore Evolution and Fracture Development Coupled Models in the Prediction of Reservoir "Sweet Spots" in Tight Sandstones 被引量:3
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作者 ZHANG Linyan ZHUO Xizhun +3 位作者 MA Licheng CHEN Xiaoshuai SONG Licai ZHOU Xingui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第3期1051-1052,共2页
The Chang-63 reservoir in the Huaqing area has widely developed tight sandstone "thick sand layers, but not reservoirs characterized by rich in oil", and it is thus necessary to further study its oil and gas enrichm... The Chang-63 reservoir in the Huaqing area has widely developed tight sandstone "thick sand layers, but not reservoirs characterized by rich in oil", and it is thus necessary to further study its oil and gas enrichment law. This study builds porosity and fracture development and evolution models in different deposition environments, through core observation, casting thin section, SEM, porosity and permeability analysis, burial history analysis, and "four-property-relationships" analysis. 展开更多
关键词 Sweet Spots in Tight Sandstones application of Pore Evolution and Fracture Development Coupled models in the Prediction of Reservoir
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Application of the Physical Quantity Field Evolution under Numerical Model in Precipitation Forecast of Yantai 被引量:1
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作者 SUN Dian-guang,HUANG Ben-feng Yantai Meteorological Bureau in Shandong Province,Yantai 264003,China 《Meteorological and Environmental Research》 CAS 2011年第11期1-4,7,共5页
[Objective] The research aimed to understand role of the forecast data about physical quantity field in precipitation forecast.[Method] By contrasting forecast and actual situation of the precipitation in Yantai durin... [Objective] The research aimed to understand role of the forecast data about physical quantity field in precipitation forecast.[Method] By contrasting forecast and actual situation of the precipitation in Yantai during 2-3 July and 12-15 September,2011,advantages and disadvantages of the different numerical forecast models (Japan fax chart,European center,MM5,Grapes and T639) were analyzed.[Result] MICAPS system could provide live situation of the physical quantity field,but couldn't provide the future evolution situation.Japan fax chart,European center,MM5,Grapes and T639 could provide future evolution situation of the physical quantity field.[Conclusion] The contrasts and analyses on forecast situations of the physical quantity fields in many precipitation processes showed that evolutions of the vertical velocity,temperature dew point difference,relative humidity and wind field at the different heights could improve forecast accuracy of the precipitation in Yantai. 展开更多
关键词 Numerical model Evolution of the physical quantity field application of precipitation forecast China
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Impact failure models and application condition of trees in debris-flow hazard mitigation 被引量:1
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作者 JIN Ke CHEN Jian-gang +3 位作者 CHEN Xiao-qing ZHAO Wan-yu SI Guang-wu GONG Xing-long 《Journal of Mountain Science》 SCIE CSCD 2021年第7期1874-1885,共12页
Forestry has played an important role in hazard mitigation associated with debris flows.Most forest mitigation measures refer to the experience of soil and water conservation,which disregard the destructive effect of ... Forestry has played an important role in hazard mitigation associated with debris flows.Most forest mitigation measures refer to the experience of soil and water conservation,which disregard the destructive effect of debris flows,causing potentially serious consequences.Determination of the effect of a forest on reducing debris-flow velocity and even stopping debris flows requires distinguishing between when the debris flow will destroy the forest and when the trees will withstand the debris-flow impact force.In this paper,we summarized two impact failure models of a single tree: stem breakage and overturning.The influences of different tree sizes characteristics(stem base diameter,tree weight,and root failure radius) and debris-flow characteristics(density,velocity,flow depth,and boulder diameter) on tree failure were analyzed.The observations obtained from the model adopted in this study show that trees are more prone to stem breakage than overturning.With an increase in tree size,the ability to resist stem breakage and overturning increases.Debris-flow density influences the critical failure conditions of trees substantially less than the debrisflow velocity,depth,and boulder diameter.The application conditions of forests in debris-flow hazard mitigation were proposed based on the analysis of the model results.The proposed models were applied in the Xiajijiehaizi Gully as a case study,and the results explain the destruction of trees in the forest dispersing zone.This work provides references for implementing forest measures for debris-flow hazard mitigation. 展开更多
关键词 Trees Impact failure model Forest application condition Debris flow mitigation
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