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分析了国内外物联网安全政策、技术、标准、产业等形势,重点强调了当前我国物联网发展中存在的安全风险,包括大连接环境下的设备风险、物联网网络本身安全风险以及物联网上承载的各类应用安全风险,提出了打造以密码为核心的物联网安全体系,加速新技术在物联网安全的应用,以新基建为契机建立物联网领域安全设备泛在化部署新体系,以多层次立体式理念确保物联网安全,呼吁供给侧需求侧建立安全协同新机制,共同促进物联网产业安全可持续发展。 相似文献
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The work presented in this paper describes the design for Graduation Project eCoordination System in our department. The proposed eCoordinator provides effective team–team, supervisor–team and coordinator–supervisors–teams collaboration. eCoordinator is an attribute based framework that serves evolving an object oriented software system into agent oriented software system. Nowadays, agent-oriented software development technologies have evolved rapidly; it is emerging as a new paradigm for constructing intelligent more autonomous software systems. Therefore, several methodologies are available and it is difficult to determine the most appropriate methodology for specific project within different domains. This is especially occurs when re-engineering current object oriented software system. The case study is going to be rebuilding a virtual graduation project coordinator in Information Technology Department at King Saud University. 相似文献
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HARE, a systematic tool to evaluate demand side measures to face sustained energy supply risk in hydrothermal power systems is presented in this paper. The main focus of the paper is to help centralized planners to systematically discuss, select, and plan the measures that better respond to the variety of critical situations that can arise due to expected energy shortage, integrate them into the usual medium-term scheduling tool and consequently keep the associated overall costs as low as possible. A medium-term definition of the system state is proposed as a decision-making aid, as well as a set of general energy saving measures that can be applied with their corresponding attributes (time delays, costs of implementation, and energy saving impact). The tool is demonstrated and applied to a simplified version of Chilean’s medium-term hydrothermal scheduling model and to a specific risk scenario experienced during 2011. The results show that it is possible to define various sets of demand side measures that avoid the impacts on the system and subsequently to select among them those with least expected implementation costs. This tool seems mainly useful for hydro-electric systems, which are more vulnerable to sustained energy supply risk. Every power system will have to go through a detailed review and planning process to implement this type of tool. 相似文献
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Enterprises in an industrial cluster could dynamically alliance in the form of cluster supply chains to share inner-cluster resources and services, and respond to the ever-fluctuating customer demands in a cost-effective way. However, an effective and feasible method enabling such dynamic cluster supply chain configuration (CSCC) lags behind practice due to the conflict of interests. Researchers are designing All-in-One theoretic models to optimize CSCC with the assumed decision details of all enterprises, while in fact clustered enterprises are seeking effective decentralized decision mechanisms which protect their decision autonomy in the frequently re-configured CSC. A newly emerged multi-disciplinary optimization method, Augmented Lagrangian Coordination (ALC), which supports the open-structure collaboration with strict optimization convergence, is thoroughly investigated in this paper and applied to solve the conflict. Through a complete analysis of CSC’s configuration policies in typical stages, a generic CSCC model is proposed and then partitioned into an ALC-based decentralized decision model by the typical decision autonomy distribution in clusters. Clustered enterprises collaborate vertically and laterally along the ALC model through multi-dimensional couplings to achieve the overall consistency and optimality. Results have proved the effectiveness of ALC for CSCC problem. A set of sensitivity analysis is also conducted to find out the condition in which an order has to be fulfilled in a CSC and the most appropriate configuration. 相似文献
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针对高含盐氨氮废水,选择具有不同功能基团的树脂为载体,进行负载Cu2+改性制得载铜树脂并对其处理高含盐氨氮废水的性能进行研究。在筛选出最佳载铜树脂的基础上,研究pH及Na+浓度、树脂投加量、反应时间对载铜树脂处理高含盐氨氮废水效果的影响,通过对吸附氨氮前后的载铜树脂进行SEM和EDS表征分析并构建吸附动力学模型以进一步探究配位吸附的过程。结果表明,Cu2+可与螯合树脂D751稳定结合且在宽pH值下均表现出耐盐性和良好的氨氮吸附效果;在室温(25℃)、pH=11及Na+浓度4 g/L、树脂投加量8 g/L、反应时间60 min的条件下,D751载铜树脂对氨氮的去除率为34.8%。D751载铜树脂吸附氨氮后其表面出现明显的晶状结构物质,该物质可能为铜氨络合物。D751载铜树脂对高含盐氨氮的吸附符合准二级动力学模型。 相似文献
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Histidine, a versatile proteinogenic amino acid, plays a broad range of roles in all living organisms and behaves as a key mediator of the interactions of biomolecules with inorganic constituents. The self-assembly of histidine-rich peptides and proteins is critical in biology, as the histidine unit is both a multifunctional regulator and an ideal motif for the construction of complex biological structures. In particular, non-covalent interactions between the imidazole ring and other molecular building blocks and metal ions are routinely employed to generate these complexes. Therefore, this strategy can be duplicated in an artificial context to create sophisticated bioactive materials. In this review, we first highlight a clear perspective of the bio-inspired design strategies which can replicate the hierarchical structure of biological systems allowing the engineering of the supramolecular self-assembly of histidine-functionalized peptides. We further summarize advancements in the field of peptide supramolecular structures incorporating histidine residues in the peptide backbone to generate organized functional supramolecular biomaterials with customizable features. We also discuss significant advances and future prospects in supramolecular self-assembly of histidine-functionalized peptides, as well as provide an overview of advanced techniques for the fabrication of histidine-based biomaterials for bio-nanotechnology, optoelectronic engineering, and biomedicine. Overall, artificial supramolecular materials based on histidine functionalized peptides, motivated by the intriguing properties discovered in natural proteins, bear the potential to boost the creation of sustainable bio-inspired materials. 相似文献
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高碾压混凝土重力坝不同功能部位"结构特性"与"材料性能"的差异产生的变形协调问题直接关系到工程结构的安全运行,现阶段变形协调分析多是对结构变形和受力进行分析,对异种材料变形协调机理认识不足,缺乏理论基础研究。本文基于界面力学理论,考虑混凝土坝分区中常见的两种双材料界面形式与理想界面的连续边界条件,基于奇异性特征值的特征方程,提出了以应力奇异性特征值作为异种材料变形协调的评价指标,并通过有限元分析验证了理论计算的正确性与有效性;进而分析了界面结合角度和异种材料组合对单侧自由界面端与埋入界面折点处应力奇异性的影响,通过非均质有限元数值仿真分析了复合试件破坏模式,研究了抗压强度与应力奇异性特征值的关系;最后通过统计实际混凝土坝工程中不同坝段内的双材料界面的材料参数(弹性模量)与结构参数(界面形式与结合角度),计算奇异性特征值,评价了该工程中界面的变形协调特性,为高混凝土坝分区材料-结构设计与材料选取提供新的思路。 相似文献
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