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1.
传统房屋租赁平台存在着用户隐私安全与租赁双方权益难以得到保障等问题。区块链技术是一种去中心化、不可篡改、可追溯、可编程的分布式账本技术,基于区块链的房屋租赁分配系统是解决当前房屋租赁行业相关问题的综合性解决方案。重点研究在非信任情况下通过密码学技术保证用户数据安全与隐私安全,结合时间戳技术将交易信息上链,以解决交易双边信用等问题。使用智能合约实现分布式的自适应寻租与匹配策略,通过对上海市地区进行实验测试,结果表明:以智能合约为基础的房屋自适应寻租匹配策略能够有效保证房屋租赁双方的权益。  相似文献   
2.
This paper concentrates on a class of decentralized convex optimization problems subject to local feasible sets, equality and inequality constraints, where the global objective function consists of a sum of locally smooth convex functions and non-smooth regularization terms. To address this problem, a synchronous full-decentralized primal-dual proximal splitting algorithm (Syn-FdPdPs) is presented, which avoids the unapproximable property of the proximal operator with respect to inequality constraints via logarithmic barrier functions. Following the proposed decentralized protocol, each agent carries out local information exchange without any global coordination and weight balancing strategies introduced in most consensus algorithms. In addition, a randomized version of the proposed algorithm (Rand-FdPdPs) is conducted through subsets of activated agents, which further removes the global clock coordinator. Theoretically, with the help of asymmetric forward-backward-adjoint (AFBA) splitting technique, the convergence results of the proposed algorithms are provided under the same local step-size conditions. Finally, the effectiveness and practicability of the proposed algorithms are demonstrated by numerical simulations on the least-square and least absolute deviation problems.  相似文献   
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在Web2.0的环境下,UGC素材进入了新闻报道,同时新闻报道对UGC类型又进行选择。互联网为传统新闻媒体开辟了新"路线",并没有使新闻权威消解。然而,要想UGC繁盛下的新闻权威不被消解,关键一点新闻从业者必须坚持新闻专业主义原则。  相似文献   
5.
This work is devoted to investigating the asynchronous quantized control of discrete-time Markovian switching Lur’e systems with an event-triggered mechanism. To model the asynchronous controller and the quantization effects, the hidden Markov model is employed. For reducing the burden of communication bandwidth, an event-triggered mechanism is adopted. By choosing the proper stochastic Lyapunov functional, sufficient conditions are derived. Finally, a practical example is given to illustrate the effectiveness and efficiency of the proposed method.  相似文献   
6.
中国典籍,尤其是类书的类目分类究竟依据何种文化原则,似乎少有人问津.法国学者爱弥儿·涂尔干与马塞尔·莫斯合著的《原始分类》中国部分,为理解中国原始分类与中国典籍分类的渊源关系搭建了桥梁.本文就《原始分类》中国部分展开梳理,对真知、误读、差异加以认可、纠正、弥合,揭示中国原始分类的基本特征及其体系并借之对中国典籍类目的分类原则与依据进行探讨,以勾勒出其与原始分类渊源的大体状貌.  相似文献   
7.
For the typical color detects of polysilicon wafers, i.e., edge discoloration, color inaccuracy and color non-uniformity, a new integrated machine vision detection method is proposed based on an HSV color model. By transforming RGB image into three-channel HSV images, the HSV model can efficiently reduce the disturbances of complex wafer textures. A fuzzy color clustering method is used to detect edge discoloration by defining membership function for each channel image. The mean-value classi- fying method and region growing method are used to identify the other two defects, respectively. A vision detection system is developed and applied in the produc- tion of polysilicon wafers.  相似文献   
8.
针对目前磨料流加工存在的问题,本文设计了一种新型的细孔磨料流加工机床.从浆料流变学的角度,推导出磨料流加工中壁面剪应力的数学表达式.结合数学表达式对其加工原理进行了分析,得出新型磨料流加工机床研磨内孔的3种主要方式.相比只存在粘性剪应力的研磨加工,新型研磨机床采用复合粘性剪应力和雷诺剪应力的工作方式,其加工效率得到明显提高.最后给出细孔磨料流加工机床在喷油器体内孔研磨加工的应用实例.  相似文献   
9.
Amorphous InGaZnO (a-IGZO) films were deposited on the corning eagle XG (EXG) glass substrates using magnetron sputtering method. The structure, surface morphology, electrical and optical properties of these films were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), semiconductor parameter analyzer and spectrophotometry, respectively. The influence of oxygen flow on the electrical properties of IGZO thin films was studied, showing that increasing oxygen flow changes the resistivity with six orders of magnitude. The contact resistance of ITO/IGZO is 7.35×10−2 Ω·cm2, which suggests that a good ohmic contact exists between In2O3: Sn (ITO) and IGZO film.  相似文献   
10.
As a parallel programming model, Map-Reduce is used for distributed computing of massive data. Map-Reduce model encapsulates the details of parallel implementation, fault-tolerant processing, local computing and load balancing, etc., provides a simple but powerful interface. In case of having no clear idea about distributed and parallel programming, this interface can be utilized to save development time. This paper introduces the method of using Hadoop, the open-source Map-Reduce software platform, to combine PCs to carry out scalable parallel computing. Our experiment using 12 PCs to compute N-body problem based on Map-Reduce model shows that we can get a 9.8x speedup ratio. This work indicates that the Map-Reduce can be applied in scalable parallel computing.  相似文献   
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