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61.
在新时期倡导节能和环保的可持续性发展观的背景下,针对住宅建筑的经济性原则和高新技术的高成本问题,提出多管齐下、从低技术创新的角度来回应建筑的可持续性设计问题,实现生态住宅的可消费性。通过对早期生态住宅的典范——巴特罗公寓通风设计的研析,展示了低技术策略的创造性价值和非常规思路;同时通过重新审视自然通风这一传统技术的现实意义及其在现代生态住宅设计中的应用潜力,借鉴巴特罗公寓的创新启示,提倡在当代可持续性住宅设计中进一步拓展低技术思路。  相似文献   
62.
Web-based post-processing visualization system for finite element analysis   总被引:1,自引:0,他引:1  
In this paper, we propose and implement a website of post-processing system for finite element analysis (WebDFEA). Finite element analysis is a computer-aided engineering tool and is popular for static/dynamic structure analysis. It includes three processing systems where post-processing system is to graphically demonstrate the analysis result of a structure model analyzed by finite element method. WebDFEA performs as a website. It is cross-platform because it can auto-detect a client computer platform and auto-download proper OpenGL API for drawing computer graphics. It can draw precise graphics on webpage which can be free controlled by the mouse as a manner in professional software. A database server is involved to store finite element model data and its analysis result. The graphic user interface (GUI) of WebDFEA is a flexible GUI comprising three parts: the switch buttons designed by HTML, the display board and the color bar both developed in Java. The three components are independent and cooperative with each other. They can be recombined without running errors for different purposes. A ship hull section with half a hatch is chosen as the study case to test WebDFEA website. Its finite element model comprises 11,442 triangle elements (shapes). The timeframe starting when WebDFEA is connected to the end when the model is demonstrated is acceptable.  相似文献   
63.
This paper proposes and investigates a novel analytical model of a hybrid channel allocation algorithm within wireless cellular networks. Each cell of the network consists of a predesigned fixed number of channels and the network may approve the request for extra channels for both new and handoff calls if all predesigned channels are occupied. This approval depends on the types of new and handoff calls, as well as the number of approved additional channels in the cell. If a request is denied for the arriving new call, this call will be blocked and cleared from the system. However, if a request is denied for an arriving handoff call, this call will not be blocked immediately but rather put on hold in a buffer with finite space. The implication behind this is to give priority to handoff calls. For this proposed hybrid channel allocation scheme, we first obtain the stationary distribution of each cell when there are i calls connecting to the system and j calls holding on in the buffer. We then derive new and handoff call blocking probabilities, the average number of borrowed channels, and the average delay period of handoff calls. The numerical results show that the proposed hybrid algorithm is more efficient than other approaches, specifically, in comparison with methods without a borrowing capability for new calls and those without a reserved buffer priority for handoff calls. The idea and results presented in this paper are expected to provide guidelines for field data processing within current wireless and mobile network design and performance evaluation.  相似文献   
64.
Excimer laser ablation technique was introduced into this work to fabricate a passive planar micromixer on the PMMA substrate. T-junction shaped and width-changed S-shaped microchannels were both designed in this micromixer to enhance mixing effect. The mixing experiment of distilled water and Rhodamine B with injection flow rate of 500 and 1,500 μm/s validates the mixing effectivity of this micromixer, and indicates the feasibility of excimer laser ablation in the microfabrication of μ-TAS device.  相似文献   
65.
66.
Multimedia Tools and Applications - Reversible data hiding based on prediction methods is a data hiding technique wherein secret bits can be efficiently hidden into cover images. In this paper, we...  相似文献   
67.
Multimedia Tools and Applications - Data hiding is a technique that embeds a cluster of secret messages into the original image. The image with secret messages can be distributed on the Internet...  相似文献   
68.
We construct two sets of incomplete and extendible quantum pure orthogonal product states (POPS) in general bipartite high-dimensional quantum systems, which are all indistinguishable by local operations and classical communication. The first set of POPS is composed of two parts which are \(\mathcal {C}^m\otimes \mathcal {C}^{n_1}\) with \(5\le m\le n_1\) and \(\mathcal {C}^m\otimes \mathcal {C}^{n_2}\) with \(5\le m \le n_2\), where \(n_1\) is odd and \(n_2\) is even. The second one is in \(\mathcal {C}^m\otimes \mathcal {C}^n\) \((m, n\ge 4)\). Some subsets of these two sets can be extended into complete sets that local indistinguishability can be decided by noncommutativity which quantifies the quantumness of a quantum ensemble. Our study shows quantum nonlocality without entanglement.  相似文献   
69.
可穿戴设备的显示系统往往受其体积和功耗的限制而非常的小巧,近些年来OLED显示屏因为较LCD显示屏有刷新速度快、功耗低的诸多优点,被广泛采用在可装戴设备中,如智能手表、可穿戴医疗仪器等.本文采用MSP430F1611低功耗处理器模拟SPI协议对OLED显示屏控制,并采用低功耗技术处理,实现了低功耗的可穿戴设备的显示系统.  相似文献   
70.
数字城管建设过程中积累了大量的执法信息,分析和挖掘这些信息具有重要的意义。介绍了一个城市管理科学执法分析决策系统的具体设计和实现,该系统基于Java EE平台,采用MVC设计模式,使用Struts 2和Hibernate框架,综合运用了统计分析方法。该系统能为城市管理的科学执法提供决策支持。  相似文献   
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