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51.
This research proposes ACARDS (Augmented-Context bAsed RecommenDation Service) framework that is able to utilize knowledge over the Linked Open Data (LOD) cloud to recommend context-based services to users. To improve the level of user satisfaction with the result of the recommendation, the ACARDS framework implements a novel recommendation algorithm that can utilize the knowledge over the LOD cloud. In addition, the noble algorithm is able to use new concepts like the enriched tags and the augmented tags that originate from the hashtags on the SNSs materials. These tags are utilized to recommend the most appropriate services in the user’s context, which can change dynamically. Last but not least, the ACARDS framework implements the context-based reshaping algorithm on the augmented tag cloud. In the reshaping process, the ACARDS framework can recommend the highly receptive services in the users’ context and their preferences. To evaluate the performance of the ACARDS framework, we conduct four kinds of experiments using the Instagram materials and the LOD cloud. As a result, we proved that the ACARDS framework contributes to increasing the query efficiency by reducing the search space and improving the user satisfaction on the recommended services.  相似文献   
52.
The large scale emergence in the last decade of various cloud solutions, ranging from software-as-a-service (SaaS) based solutions for business process management and implementation to very sophisticated private cloud solutions capable of high performance computing (HPC) and efficient virtualization, constitute the building blocks for engineering the next generation of flexible enterprise systems that can respond with great agility to changes in their environment. These new technologies are adopted at a certain level by manufacturing enterprises in order to advance in a new era of mass customization where flexibility, scalability and agility are the differentiating factors. In this context, this paper introduces the virtualized manufacturing execution system (vMES), an intermediate layer in the manufacturing stack, and discusses the advantages and limitations offered by this approach for manufacturing enterprises. A classification of MES workloads based on the ISA-95 function model is presented, focusing on the virtualization techniques suitable for each workload, considering the algorithms and technologies used and the virtualization overhead. A pilot vMES implementation using a parallel process for smart resource provisioning and automatic scaling is also presented. The pilot implementation using six Adept robots and one IBM CloudBurst 2.1 private cloud and an ISA-95 based MES is described; the virtualization sequence is analyzed in several scenarios of resource workload collocation on physical cloud blades with and without perturbations.  相似文献   
53.
To assess the dynamic impact of intermittency of rapidly increasing solar photovoltaic generation on the grid, this article presents the modeling and integration of the components that need to be considered, including the solar photovoltaic plant, battery energy storage system, grid-tied interface, and associated control systems. The complexity and accuracy of these models are suitable for evaluating the transient impact on bulk power systems. Of particular interest is the grid inertial response in such situations as different penetration levels of solar generation and fast cloud transient induced solar generation decrease coupled with outages that recurrently occur in the grid, e.g., a generator trip. The impact of such events on the grid frequency responses is investigated using a simplified simulation approach to account for the locational or spatial irradiance variation patterns and cloud movements. Responsive battery energy storage systems are recognized as an effective means to improve the inertial response.  相似文献   
54.
本文介绍了新疆地区在大厚度湿陷性黄土区域地基处理方法适用性的探究,根据工程实例归纳总结了不同处理方法的优缺点,总结提出适宜的处理方法及需要考虑各种因素,为相关工程提供借鉴。  相似文献   
55.
Abstract

Addition of organic solvents is known to change the properties of amphiphiles through modification of bulk phase. Amitriptyline hydrochloride (AMT) is a tricyclic amphiphilic drug which is usually used as an antidepressant. In drug delivery, the cloud point (CP) of the drug is an important parameter. This article discusses the effects of ethanol–water (EtOH–WR) compositions on the energetic parameters, such as changes in Gibbs energy of clouding (ΔsG0), enthalpy of clouding (ΔsH0), and entropy of clouding (TΔsS0) of AMT-additive systems. Monovalent alkali halide salts, cationic conventional surfactants, and gemini surfactants were used as additives in the EtOH–WR mixed media whose compositions were varied between 0 and 15% (w/w). The ΔsG0 values are positive for all the additives and the values decrease with the rise in mole fractions of the additives. The ΔsH0 and TΔsS0 were noted to be positive except for KF in 15% EtOH–WR mixed media.  相似文献   
56.
《Ceramics International》2020,46(4):4148-4153
The ferroelectric photovoltaic (FPV) effect obtained in inorganic perovskite ferroelectric materials has received much attention because of its large potential in preparing FPV devices with superior stability, high open-circuit voltage (Voc) and large short-circuit current density (Jsc). In order to obtain suitable thickness for the ferroelectric thin film as light absorption layer, in which, the sunlight can be fully absorbed and the photo-generated electrons and holes are recombined as few as possible, we prepare Pb0.93La0.07(Zr0.6Ti0.4)0.9825O3 (PLZT) ferroelectric thin films with different layer numbers by the sol-gel method and based on these thin films, obtain FPV devices with FTO/PLZT/Au structure. By measuring photovoltaic properties, it is found that the device with 4 layer-PLZT thin film (~300 nm thickness) exhibits the largest Voc and Jsc and the photovoltaic effect obviously depends on the value and direction of the poling electric field. When the device is applied a negative poling electric field, both the Voc and Jsc are significantly higher than those of the device applied the positive poling electric field, due to the depolarization field resulting from the remnant polarization in the same direction with the built-in electric field induced by the Schottky barrier, and the higher the negative poling electric field, the larger the Voc and Jsc. At a -333 kV/cm poling electric field, the FPV device exhibits the most superior photovoltaic properties with a Voc of as high as 0.73 V and Jsc of as large as 2.11 μA/cm2. This work opens a new way for developing ferroelectric photovoltaic devices with good properties.  相似文献   
57.
任亚峰 《陕西煤炭》2020,39(1):65-69,50
煤层底板承压水突出是发生水害事故的原因之一,要减少该类事故的发生,需对底板突水危险性进行准确评价。为保障里必井田承压水带压开采的安全进行,基于煤层底板突水研究理论分析,采用常规突水系数法和等效厚度突水系数法,分别对里必井田内3#煤和15#煤的奥灰水突水危险性进行了研究。研究发现,奥灰水对于3#煤的开采影响不大,但在局部构造及陷落柱发育地段及采区东北部区域仍存在一定的突水可能性;奥灰水对15#煤开采具有较大威胁,大部分区域具有较大突水危险性。等效岩层厚度法计算的突水系数考虑了不同性质岩层的岩石强度和阻水能力,计算更接近生产实际,结果更可靠;且在对突水系数法进一步优化后,其评价的结果可以更精确。  相似文献   
58.
针对传统的卷积神经网络(CNN)不能直接处理点云数据,需先将点云数据转换为多视图或者体素化网格,导致过程复杂且点云识别精度低的问题,提出一种新型的点云分类与分割网络Linked-Spider CNN。首先,在Spider CNN基础上通过增加Spider卷积层数以获取点云深层次特征;其次,引入残差网络的思想在每层Spider卷积增加短连接构成残差块;然后,将每层残差块的输出特征进行拼接融合形成点云特征;最后,使用三层全连接层对点云特征进行分类或者利用多层卷积层对点云特征进行分割。在ModelNet40和ShapeNet Parts数据集上将所提网络与PointNet、PointNet++和Spider CNN等网络进行对比实验,实验结果表明,所提网络可以提高点云的分类精度和分割效果,说明该网络具有更快的收敛速度和更强的鲁棒性。  相似文献   
59.
基于双边市场理论,分析了垄断的云制造平台在收取会员费和交易费模式下的最优定价策略,并利用数值仿真分析了两种收费模式下平台最优利润的差异。结果表明:两种模式下的单边最优定价均与缴费方的自网络外部性系数和免费方的交叉网络外部性系数负相关,与免费方用户数量正相关,双边最优定价受各参数影响方向取决于供需方各参数的相对大小;单边定价对象为用户数量相对较多一方,平台两边用户数量相对平衡时,单边最优定价等于双边最优定价,双边定价时的平台最优利润高于单边定价;最优定价策略由平台内交易次数决定,交易次数较多时双边收取交易费模式更优,交易次数较少时双边收取会员费更优,交易次数临界值取决于平台内网络效应和用户数量。  相似文献   
60.
数据库云化部署技术研究   总被引:2,自引:0,他引:2  
云计算虚拟化技术具备弹性可扩展、自动迁移(高可用)、自动恢复(高可靠)等特征,然而数据库系统自身技术的复杂性对在云计算环境中部署工作提出了调整.在研究与分析私有云计算环境中数据库系统部署模式的基础上,在实际应用系统环境中重点验证了不同数据库系统采用单虚拟机部署模式时事务性能基准测试中的性能表现,通过与数据库在物理服务器部署方式下的性能对比,验证了数据库系统云化部署的可行性.  相似文献   
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