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Analysis on the Development of Smart Logistics Business Platform Model and Innovation Mechanism
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作者 TIAN Yu 《外文科技期刊数据库(文摘版)经济管理》 2021年第3期147-150,共6页
Smart logistics is a new direction for the development of the current logistics industry. This paper mainly analyzes and summarizes the main development status of China's smart logistics and related policies. It f... Smart logistics is a new direction for the development of the current logistics industry. This paper mainly analyzes and summarizes the main development status of China's smart logistics and related policies. It finds that China's current investment in innovation and the application of smart systems in the smart logistics industry are gradually increasing, indicating that China's entire logistics system is also in constant transition towards smart direction. However, there is still a certain gap between the related technology application level and the international developed countries, and these problems should be solved in a timely manner. At the same time, this paper also puts forward specific suggestions on relevant issues, hoping to provide certain reference value for the development of China's smart logistics business platform model and innovation mechanism. 展开更多
关键词 smart logistics business platform model development of the innovation mechanism
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Error model identification of inertial navigation platform based on errors-in-variables model 被引量:6
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作者 Liu Ming Liu Yu Su Baoku 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期388-393,共6页
Because the real input acceleration cannot be obtained during the error model identification of inertial navigation platform, both the input and output data contain noises. In this case, the conventional regression mo... Because the real input acceleration cannot be obtained during the error model identification of inertial navigation platform, both the input and output data contain noises. In this case, the conventional regression model and the least squares (LS) method will result in bias. Based on the models of inertial navigation platform error and observation error, the errors-in-variables (EV) model and the total least squares (TLS) method axe proposed to identify the error model of the inertial navigation platform. The estimation precision is improved and the result is better than the conventional regression model based LS method. The simulation results illustrate the effectiveness of the proposed method. 展开更多
关键词 errors-in-variables model total least squares method inertial navigation platform error model identification
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Uncertain optimal model and solving method to platform scheduling problem in battlefield 被引量:2
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作者 Yu Sun Peiyang Yao +1 位作者 Dongdong Shui Jieyong Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第1期157-165,共9页
The platform scheduling problem in battlefield is one of the important problems in military operational research.It needs to minimize mission completing time and meanwhile maximize the mission completing accuracy with... The platform scheduling problem in battlefield is one of the important problems in military operational research.It needs to minimize mission completing time and meanwhile maximize the mission completing accuracy with a limited number of platforms.Though the traditional certain models obtain some good results,uncertain model is still needed to be introduced since the battlefield environment is complex and unstable.An uncertain model is prposed for the platform scheduling problem.Related parameters in this model are set to be fuzzy or stochastic.Due to the inherent disadvantage of the solving methods for traditional models,a new method is proposed to solve the uncertain model.Finally,the practicability and availability of the proposed method are demonstrated with a case of joint campaign. 展开更多
关键词 operational research platform scheduling uncertain model solving method.
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Transformation from computation independent model to platform independent model with pattern 被引量:1
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作者 曹晓夏 缪淮扣 陈怡海 《Journal of Shanghai University(English Edition)》 CAS 2008年第6期515-523,共9页
Model driven architecture(MDA) is an evolutionary step in software development.Model transformation forms a key part of MDA.The transformation from computation independent model(CIM) to platform independent model(PIM)... Model driven architecture(MDA) is an evolutionary step in software development.Model transformation forms a key part of MDA.The transformation from computation independent model(CIM) to platform independent model(PIM) is the first step of the transformation.This paper proposes an approach for this transformation with pattern.In this approach, we take advantage of"reuse"from various standpoints.Feature model is used to describe the requirement of the application.This can help us bring"reuse"into effect at requirement level.Moreover we use pattern to transform CIM to PIM.This can help us bring"reuse"into effect at development level.Meanwhile, pattern was divided into four hierarchies.Different hierarchies of pattern are used to help us utilize reuse at different phase of development.From another standpoint, feature model describes the problem of a domain while pattern describe the problem across domains.This can help us reuse the element in and across domains.Finally, the detailed process of the transformation is given. 展开更多
关键词 model driven architecture (MDA) computation independent model (CIM) platform independent model (PIM) pattern architecture
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Statistical Modeling of the High Altitude Platform Dual-Polarized MIMO Propagation Channel 被引量:5
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作者 Mingchuan Yang Shuo Zhang +2 位作者 Xinye Shao Qing Guo Wenyan Tang 《China Communications》 SCIE CSCD 2017年第3期43-54,共12页
In order to investigate the benefit of multiple-input multiple-output(MIMO) technique applying to the high altitude platform(HAP), a 2×2 MIMO statistical model, which can accurately describe the channel between H... In order to investigate the benefit of multiple-input multiple-output(MIMO) technique applying to the high altitude platform(HAP), a 2×2 MIMO statistical model, which can accurately describe the channel between HAP and high-speed train, is presented. And dual polarization diversity is particularly considered. Based on first-order three-state Markov chain, the single-input single-output(SISO) channel, a subset of the MIMO channel is first established. The ray tracing approach applied to the digital relief model(DRM) which covers the railway between Xi'an and Zhengzhou is used to obtain the state probability vector and matrix of the state transition probability. The proposed model considers both Doppler shift and temporal correlation, and the polarization correlation and spatial correlation statistical properties of large-scale fading and smallscale fading are analyzed. Moreover, useful numerical results on the MIMO HAP channel outage capacity are provided based on which, significant capacity gains with respect to the conventional SISO case are illustrated. Such statistical channel model can be applied to the future wireless communication system between HAP and high-speed train. 展开更多
关键词 high altitude platform(HAP) channel model multiple-input multiple-output(MIMO) polarization diversity
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Utilizing Occupancy Models and Platforms-of-Opportunity to Assess Area Use of Mother-Calf Humpback Whales 被引量:1
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作者 J. J. Currie S. H. Stack +1 位作者 J. A. McCordic J. Roberts 《Open Journal of Marine Science》 2018年第2期276-292,共17页
The Hawaiian Islands, and particularly the Maui 4-island region, are a critical breeding and calving habitat for humpback whales (Megaptera novaeangliae) belonging to the Hawaii distinct population segment. Our aims w... The Hawaiian Islands, and particularly the Maui 4-island region, are a critical breeding and calving habitat for humpback whales (Megaptera novaeangliae) belonging to the Hawaii distinct population segment. Our aims were to test the use of platforms-of-opportunity to determine trends in mother-calf pod use of the region and to present opportunistic platforms as an alternative method of long-term, cross-seasonal monitoring. Data were collected from whale watching vessels over a 4-year period and analyzed using occupancy models to determine the probability of habitat use of pods with calves and pods without calves within the study area. Detection probability was influenced by survey effort and month for all pod types with detection of adult only pods further influenced by year. Pods with a calf showed a preference for shallow (<100 meters) low latitude waters (<20.7°N), while pods without a calf preferred deeper waters (>75 meters). Results presented here align with previous work, both in Hawaii and in other breeding grounds, which show a distinct segregation of mothers with a calf from other age-classes of humpback whales. The need for long-term continuous monitoring of cetacean populations is crucial to ensure species conservation. Data collected aboard platforms-of-opportunity, as presented here, provide important insight on humpback whale spatial and temporal distribution, which are essential for species protection and management. 展开更多
关键词 Humpback WHALE OCCUPANCY model platform of OPPORTUNITY WHALE and DOLPHIN Tracker Area Use
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Three-dimensional cell culture systems as an in vitro platform for cancer and stem cell modeling 被引量:16
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作者 Nipha Chaicharoenaudomrung Phongsakorn Kunhorm Parinya Noisa 《World Journal of Stem Cells》 SCIE 2019年第12期1065-1083,共19页
Three-dimensional(3D)culture systems are becoming increasingly popular due to their ability to mimic tissue-like structures more effectively than the monolayer cultures.In cancer and stem cell research,the natural cel... Three-dimensional(3D)culture systems are becoming increasingly popular due to their ability to mimic tissue-like structures more effectively than the monolayer cultures.In cancer and stem cell research,the natural cell characteristics and architectures are closely mimicked by the 3D cell models.Thus,the 3D cell cultures are promising and suitable systems for various proposes,ranging from disease modeling to drug target identification as well as potential therapeutic substances that may transform our lives.This review provides a comprehensive compendium of recent advancements in culturing cells,in particular cancer and stem cells,using 3D culture techniques.The major approaches highlighted here include cell spheroids,hydrogel embedding,bioreactors,scaffolds,and bioprinting.In addition,the progress of employing 3D cell culture systems as a platform for cancer and stem cell research was addressed,and the prominent studies of 3D cell culture systems were discussed. 展开更多
关键词 Three-dimensional CULTURES CANCER Stem cells Disease modelING In VITRO screening platform
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Nonlinear optimal model and solving algorithms for platform planning problem in battlefield 被引量:2
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作者 WANG Xun YAO Peiyang +1 位作者 ZHANG Jieyong WAN Lujun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第5期983-994,共12页
Platform planning is one of the important problems in the command and control(C2) field. Hereto, we analyze the platform planning problem and present nonlinear optimal model aiming at maximizing the task completion qu... Platform planning is one of the important problems in the command and control(C2) field. Hereto, we analyze the platform planning problem and present nonlinear optimal model aiming at maximizing the task completion qualities. Firstly, we take into account the relation among tasks and build the single task nonlinear optimal model with a set of platform constraints. The Lagrange relaxation method and the pruning strategy are used to solve the model. Secondly, this paper presents optimization-based planning algorithms for efficiently allocating platforms to multiple tasks. To achieve the balance of the resource assignments among tasks, the m-best assignment algorithm and the pair-wise exchange(PWE)method are used to maximize multiple tasks completion qualities.Finally, a series of experiments are designed to verify the superiority and effectiveness of the proposed model and algorithms. 展开更多
关键词 platform planning nonlinear optimal model Lagrange relaxation method m-best algorithm pair-wise exchange(PWE)
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Numerical Modeling of a Spar Platform Tethered by a Mooring Cable 被引量:3
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作者 ZHU Xiangqian YOO Wan-Suk 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第4期785-792,共8页
Virtual simulation is an economical and efficient method in mechanical system design. Numerical modeling of a spar platform, tethered by a mooring cable with a spherical joint is developed for the dynamic simulation o... Virtual simulation is an economical and efficient method in mechanical system design. Numerical modeling of a spar platform, tethered by a mooring cable with a spherical joint is developed for the dynamic simulation of the floating structure in ocean. The geometry modeling of the spar is created using finite element methods. The submerged part of the spar bears the buoyancy, hydrodynamic drag force, and effect of the added mass and Froude-Krylov force. Strip theory is used to sum up the forces acting on the elements. The geometry modeling of the cable is established based on the lumped-mass-and-spring modeling through which the cable is divided into 10 elements. A new element-fixed local frame is used, which is created by the element orientation vector and relative velocity of the fluid, to express the loads acting on the cable. The bottom of the cable is fixed on the seabed by spring forces, while the top of the cable is connected to the bottom of the spar platform by a modified spherical joint. This system suffers the propagating wave and current in the X-direction and the linear wave theory is applied for setting of the propagating wave. Based on the numerical modeling, the displacement-load relationships are analyzed, and the simulation results of the numerical modeling are compared with those by the commercial simulation code, Proteus DS. The comparison indicates that the numerical modeling of the spar platform tethered by a mooring cable is well developed, which provides an instruction for the optimization of a floating structure tethered by a mooring cable system. 展开更多
关键词 numerical modeling dynamic simulation spar platform mooring cable spherical joint
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Pig Price Fluctuations and Forecasting Model Based on Information Platform
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作者 Xi ZHOU 《Asian Agricultural Research》 2016年第9期16-19,共4页
Pork is common in people's daily life consumption,and it accounts for more than half of all meats. By collecting data information published by Bureau of Statistics and Bureau of Agriculture,this paper makes a stat... Pork is common in people's daily life consumption,and it accounts for more than half of all meats. By collecting data information published by Bureau of Statistics and Bureau of Agriculture,this paper makes a statistical analysis of the influence of price fluctuation in the pork market on China's pork production,and finds that China's pork production shows a general trend of fluctuations due to the impact of price factors.According to the predecessors' studies on the factors influencing pig market price,combined with the actual situation of pig breeding in China,this paper uses the latest website data released by the government's public information platform to establish a forecasting model. 展开更多
关键词 Pig price fluctuations Information platform Forecasting model
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Modeling the Pressure Distribution and the Changes of Water Level around the Offshore Platforms Exposed to Waves, Using the Numerical Model of Flow 3D 被引量:1
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作者 Milad Rashidinasab Mehdi Behdarvandi Askar 《Computational Water, Energy, and Environmental Engineering》 2017年第1期97-106,共10页
The humans’ need to use the oceans for exploration and extraction of oil has led to the development of engineering science in the field of offshore structures. Since it’s important to examine the offshore structures... The humans’ need to use the oceans for exploration and extraction of oil has led to the development of engineering science in the field of offshore structures. Since it’s important to examine the offshore structures from different aspects and perspectives, we would have to evaluate many different parameters about them. So categorizing these parameters can help to perform their related analysis with more accuracy and more details. Due to the efficient force it exerts on the structure, the pressure distribution around every marine or hydraulic structure has a significant importance, and it even accounts for one of the dominant issues in designing and building of such structures. In the present study, an oil platform located in Phase 15 of South Pars oil fields, located in the Persian Gulf waters, has been analyzed using the FLOW 3D software. The outputs indicate that the pressure of water is distributed almost hydrostatically with the depth, and its maximum reaches 0.6 MPa at the bottom. 展开更多
关键词 Pressure Distribution OFFSHORE platformS CHANGES of Water Level modelING
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Training and Implementation of Subjective Questions Scoring System Based on the Baidu Qianfan Model Platform
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作者 Xiaoyun Zhu 《Journal of Contemporary Educational Research》 2024年第11期227-232,共6页
Leveraging the Baidu Qianfan model platform,this paper designs and implements a highly efficient and accurate scoring system for subjective questions,focusing primarily on questions in the field of computer network te... Leveraging the Baidu Qianfan model platform,this paper designs and implements a highly efficient and accurate scoring system for subjective questions,focusing primarily on questions in the field of computer network technology.The system enhances the foundational model by utilizing Qianfan’s training tools and integrating advanced techniques,such as supervised fine-tuning.In the data preparation phase,a comprehensive collection of subjective data related to computer network technology is gathered,cleaned,and labeled.During model training and evaluation,optimal hyperparameters and tuning strategies are applied,resulting in a model capable of scoring with high accuracy.Evaluation results demonstrate that the proposed model performs well across multiple dimensions-content,expression,and development scores-yielding results comparable to those of manual scoring. 展开更多
关键词 Subjective score Natural language processing Deep learning Baidu Qianfan large model platform Supervised fine-tuning model training and evaluation
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Stratigraphic Architecture and Computer Modelling of Carbonate Platform Margin,Late Ordovician Lianglitage Formation,Central Tarim Basin 被引量:2
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作者 李浩 林畅松 +3 位作者 张燕梅 张荣茜 芮志峰 黄理力 《Journal of Earth Science》 SCIE CAS CSCD 2012年第4期627-638,共12页
According to the different geometries and reflected characteristics in the seismic sections, the carbonate platform margin of the northern slope can be summarized as three basic depositional architectures in the Late ... According to the different geometries and reflected characteristics in the seismic sections, the carbonate platform margin of the northern slope can be summarized as three basic depositional architectures in the Late Ordovician Lianglitage (良里塔格) Formation of the Tazhong (塔中) uplift. The type one mainly located in the west of the carbonate platform margin, and it showed obvious imbricate progradation from the interior to the margin of the platform. The type two was in the middle of the carbonate platform margin, which showed retrogradational stacking pattern in the same transgres- sive systems tract period, and the slope strata of the platform margin showed progradational sequence in the highstand systems tract period. The type three located in the east of the carbonate platform margin, and it showed the parallel aggradational architecture. The crossing well section along the northern slope of the Tazhong carbonate platform showed that the depositional thickness became thinner from the east to the west. The thickest belt located in the east of the platform margin, and became thinner rapidly towards the basin and the platform interior. These indicated that the paleogeomorphology ofthe Tazhong uplift was probably high in the west and low in the east during the period of the Late Ordovician Lianglitage Formation. According to the interpretation of seismic profiles and the computer modelling result, the depositional architectures of sequence O31-2 showed aggradation, retrogradation and progradation from the east to the west of the carbonate platform margin during the transgression period. This meant that the accommodation became smaller gradually from the east to the west along the northern carbonate platform margin of the Tazhong uplift.The difference of the accommodation was probably caused by the difference of tectonic subsidence. Also, computer-aided modelling can be used to deeply understand the importance of various control parameters on the carbonate platform depositional architectures and processes. 展开更多
关键词 carbonate platform margin depositional architecture tectonic subsidence accommo-dation modelling.
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Evolution of behaviour of transaction subjects on energy-efficient retrofitting platform under government rewards and punishments
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作者 GUO Han-ding WANG Ke-fei 《Ecological Economy》 2025年第2期102-116,共15页
Energy-efficient retrofitting(EER)of existing buildings has significant potential for addressing energy and environmental issues.However,the traditional market trading model is characterized by an inefficient dissemin... Energy-efficient retrofitting(EER)of existing buildings has significant potential for addressing energy and environmental issues.However,the traditional market trading model is characterized by an inefficient dissemination of critical information,which leads to insufficient incentives for market participants to trade.To solve these problems,this study constructs a three-party evolutionary game model with energy saving service companies(ESCO),homeowners,and trading information platforms as the main players,analyzes the interaction and evolution of the three parties'strategies under the scenario of government rewards and penalties,and explores the effects of the three parties'initial willingness and changes of model parameters on the evolution of their strategies.There are some findings as follows:first,the positive transactions of homeowners and ESCOs have less influence on the platform side;second,compared with homeowners,the government penalties have more obvious constraints on the platform side and ESCOs;third,government subsidies and EER revenues are the important factors influencing the speed of the evolution of three-party strategies,fourth,platform service compensation,the factors governing cost and benefit sharing are pivotal in determining the alignment of strategic choices among the three parties involved.Based on the research conclusions.This study offers theoretical guidance for the advancement of platform-based market transactions for EER. 展开更多
关键词 energy-efficient retrofitting government regulation platform trading model evolutionary game
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基于SAM的水陆两栖环境感知微调策略与应用
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作者 左哲 蓝鸿 +1 位作者 覃卫 王坤 《北京理工大学学报》 北大核心 2026年第1期20-28,共9页
针对水陆两栖无人平台在不确定环境中面临的高误报率及多感知任务整合困难的问题,本研究提出了一种基于分割一切模型(segment anything model,SAM)的多模型联合环境感知方法,实现了障碍物检测与水陆域分割的统一处理.具体而言,是将U-Net... 针对水陆两栖无人平台在不确定环境中面临的高误报率及多感知任务整合困难的问题,本研究提出了一种基于分割一切模型(segment anything model,SAM)的多模型联合环境感知方法,实现了障碍物检测与水陆域分割的统一处理.具体而言,是将U-Net和YOLOv8与SAM结合,U-Net和YOLOv8负责获取目标的粗略轮廓,而SAM通过其编码−解码结构实现进一步精细分割.此外,设计了专门的微调策略以实现联合训练,进一步提升了模型的性能.本研究还构建了专有数据集USV-Dataset,并开发了数据引擎以提高标注效率.为增强模型的泛化能力,采用了4个公开数据集与USV-Dataset进行混合训练,涵盖了多样化的场景和障碍物类别.实验结果表明,该方法实现了96.8%的mPA分割精度和10 FPS的推理速度,展现出良好的泛化能力,能够满足中低速两栖无人平台的实时环境感知需求. 展开更多
关键词 水陆两栖平台 环境感知 SAM 多模型融合
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基于AI幻觉抑制的药学智能问答平台的构建与效能验证
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作者 温正旺 王嘉莹 +3 位作者 杨文月 杨昊煜 马霄 刘云 《中国药房》 北大核心 2026年第2期226-231,共6页
目的构建低“人工智能(AI)幻觉”的药学智能问答平台,提升用药咨询的准确性、一致性与可追溯性。方法利用Python代码对药品说明书进行批量结构化整理并构建本地药学知识库,基于大型语言模型实现检索与问答流程设计,并在Dify平台完成系... 目的构建低“人工智能(AI)幻觉”的药学智能问答平台,提升用药咨询的准确性、一致性与可追溯性。方法利用Python代码对药品说明书进行批量结构化整理并构建本地药学知识库,基于大型语言模型实现检索与问答流程设计,并在Dify平台完成系统集成与本地化部署。通过设计典型临床用药问题,从达峰时间、半衰期检索及肾功能减退患者剂量调整方案推理等维度,将药学智能问答平台的输出结果与在线版DeepSeek进行对比验证,评估其检索和推理结果的准确性与可靠性。结果基于本地药品说明书构建的药学智能问答平台在达峰时间、半衰期及剂量调整方案的检索和推理准确率均为100%。相比之下,在线版DeepSeek在3个维度方面的准确率分别为30%(6/20)、50%(10/20)和38%(23/60)。结论构建的药学智能问答平台能够根据临床提问精准检索并提炼本地知识库信息,能避免AI幻觉的出现,为医务人员提供可靠的用药决策支持。 展开更多
关键词 药学智能问答平台 AI幻觉 大型语言模型 DeepSeek 人工智能
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基于J2EE/MVC Model 2的公共图书管理系统的研究 被引量:14
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作者 屈霞 刘自强 张小鸣 《计算机工程与设计》 CSCD 北大核心 2009年第20期4651-4653,4657,共4页
针对当前基于Web的各图书管理系统普遍存在的缺乏业务服务能力的问题,根据多馆共建的思想,提出了一种全新的基于J2EE/MVC Model2的公共图书馆管理系统。分析了J2EE架构,阐述了系统的MVCModel2模式软件架构。给出了4层组件的开发思路,在... 针对当前基于Web的各图书管理系统普遍存在的缺乏业务服务能力的问题,根据多馆共建的思想,提出了一种全新的基于J2EE/MVC Model2的公共图书馆管理系统。分析了J2EE架构,阐述了系统的MVCModel2模式软件架构。给出了4层组件的开发思路,在业务层强调了会话外观和利用BMP精确控制数据库的设计思想,并通过实例介绍BMP的开发过程。系统性能已达到实际使用要求,系统对于树立集成管理、大图书馆管理、创新管理理念,采取科学合理的运行机制有重要意义。 展开更多
关键词 图书管理系统 J2EE MVC model 2 会话外观 Bean管理持久性
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价值共创数商模式的理论解释与经验检验——兼论平台经济的演化
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作者 罗光强 宋新宇 《中国流通经济》 北大核心 2026年第1期70-83,共14页
数字技术与共享理念共同驱动新经济演进,以平台经济为代表的新经济形态,率先打破传统市场中生产者、销售者与消费者之间的对立统一关系,建立基于信息透明的协同共生新范式。随着平台经济的高阶演化,数据作为关键生产要素,进一步推动消... 数字技术与共享理念共同驱动新经济演进,以平台经济为代表的新经济形态,率先打破传统市场中生产者、销售者与消费者之间的对立统一关系,建立基于信息透明的协同共生新范式。随着平台经济的高阶演化,数据作为关键生产要素,进一步推动消费者深度融入数字化流通与价值分配过程,形成持续互动的合作博弈与价值共创机制。数商模式以信息对称、品质共识、动态匹配、合作竞争与多方协同为主要特征,最终构建起生产者、平台商与消费者协同共创的价值循环体系。在深度挖掘京东平台大众消费品信息数据与评论文本的基础上,运用关联规则算法、倾向得分匹配和短文本主题分析模型进行经验检验。研究发现:高品质产品与平台溢价之间存在显著的强关联性,品质要素成为三方主体价值共识的基础;有机认证、地理标志等权威认证是溢价实现的核心因素,品质信任背书在数商生态中发挥着关键作用,驱动三方主体共创价值目标的实现;双认证产品之间存在“互斥隐藏效应”,消费者偏好正趋于理性;高品质产品、信息透明度与高效配送服务,是平台赢得消费者信任,实现三方共赢的核心路径。表明平台经济正在沿着数商模式演进,竞争的逻辑从聚焦价格的零和博弈,转向以品质、体验和精准价值创造为主导的生态竞争。因此,为进一步加快我国平台经济转型发展,平台商需加速人工智能与数据挖掘技术赋能,推动数商模式深化;生产者须依托平台数据实时响应市场需求,强化品质导向;各主体须协同完善认证披露与算法审查机制,共建开放共享、协同合作、可持续的数商生态,打造具有全球竞争力的数字经济新体系。 展开更多
关键词 数商模式 平台经济 信息对称 合作博弈 价值共创
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Multi Objective Robust Active Vibration Control for Flexure Jointed Struts of Stewart Platforms via H∞ and μ Synthesis 被引量:6
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作者 刘磊 王本利 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第2期125-133,共9页
Active vibration control is needed for future space telescopes, space laser communication and other precision sensitive payloads which require ultra-quiet environments. A Stewart platform based hybrid isolator with 6 ... Active vibration control is needed for future space telescopes, space laser communication and other precision sensitive payloads which require ultra-quiet environments. A Stewart platform based hybrid isolator with 6 hybrid struts is the effective system for active/passive vibration isolation over 5-250 Hz band. Using an identification transfer matrix of the Stewart platform, the coupling analysis of six channels is provided. A dynamics model is derived, and the rigid mode is removed to keep the signal of pointing control. Multi objective robust H∞ and μ synthesis strategies, based on singular values and structured singular values respectively, are presented, which simultaneously satisfy the low frequency pointing and high frequency disturbance rejection requirements and take account of the model uncertainty, parametric uncertainty and sensor noise. Then, by performing robust stability test, it is shown that the two controllers are robust to the uncertainties, the robust stability margin of H, controller is less than that of μ controller, but the order of μ controller is higher than that of H, controller, so the balanced controller reduction is provided. Additionally, the μ controller is compared with a PI controller. The time domain simulation of the μ controller indicates that the two robust control strategies are effective for keeping the pointing command and isolating the harmonic and stochastic disturbances. 展开更多
关键词 vibration isolation active struts Stewart platform H∞ synthesis μ synthesis rigid mode model reduction
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基于微助教构建分析化学混合式教学模式研究与实践
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作者 马玉花 《新疆师范大学学报(自然科学版)》 2026年第1期104-112,共9页
为了探究基于微助教平台的混合式教学模式在分析化学教学中的实践效果,本研究选取新疆师范大学化学化工学院79名学生作为研究对象,进行微助教在分析化学教学中的开发与实践对比研究。对照组采用传统教学模式进行教学,实验组采用基于微... 为了探究基于微助教平台的混合式教学模式在分析化学教学中的实践效果,本研究选取新疆师范大学化学化工学院79名学生作为研究对象,进行微助教在分析化学教学中的开发与实践对比研究。对照组采用传统教学模式进行教学,实验组采用基于微助教的混合式教学模式进行教学。分析两组学生的章节测试成绩发现,实验组学生的平均分有明显提高,表明基于微助教的混合式教学模式有效地促进学生对基础知识的掌握以及在推断和计算能力方面的提升。本研究采用问卷调查和访谈法对实验班学生进行评估,发现混合式教学模式中学生自主学习与教师指导相结合的模式显著提高了学生学习的主动性和积极性。因此,基于微助教的混合式教学模式不仅有助于培养学生的核心素养,而且构建自主学习为核心的学习框架能够增强学生对分析化学学习的信心和意愿。 展开更多
关键词 分析化学 微助教 混合式教学模式
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