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101.
孔悉茹  张磊  孔斌 《长江建设》2012,(7):225-227
自1988年建设工程监理制实施以来,建设工程监理在建设工程领域发挥了重要作用。按照国际工程管理惯例,监理机制贯穿建设项目的整个建设过程,而我国现阶段对建设项目的监理还大都局限在施工阶段。即便是施工监理,由于建设单位干预过多,监理工程师的监理职能也没有得到充分发挥。为了深入贯彻节约能源资源和保护环境等基本国策,促进经济社会发展与人口资源环境相协调,建设单位应树立科学管理理念,在工程建设全过程引入建设监理,帮助其科学管理建设项目,从而提高建设水平和投资效益。  相似文献   
102.
In order to improve the accuracy and efficiency of 3D model retrieval, the method based on affinity propagation clustering algorithm is proposed. Firstly, projection ray-based method is proposed to improve the feature extraction efficiency of 3D models. Based on the relationship between model and its projection, the intersection in 3D space is transformed into intersection in 2D space, which reduces the number of intersection and improves the efficiency of the extraction algorithm. In feature extraction, multi-layer spheres method is analyzed. The two-layer spheres method makes the feature vector more accurate and improves retrieval precision. Secondly, Semi-supervised Affinity Propagation (S-AP) clustering is utilized because it can be applied to different cluster structures. The S-AP algorithm is adopted to find the center models and then the center model collection is built. During retrieval process, the collection is utilized to classify the query model into corresponding model base and then the most similar model is retrieved in the model base. Finally, 75 sample models from Princeton library are selected to do the experiment and then 36 models are used for retrieval test. The results validate that the proposed method outperforms the original method and the retrieval precision and recall ratios are improved effectively.  相似文献   
103.
This paper mainly presents a PM multi-DOF actuator for robot in-wheels drive applications and its control method. The torque model is established based on the finite-element model of the single pair poles in 3D finite element method software. Due to the special structure of the actuator, the Euler angles are adopted for deriving the kinematics and dynamic model. To reduce the effects of uncertainties of modeling error, nonlinear friction and external disturbances in the system, an approximation of neural network adaptive control method is applied to the actuator. The computation and simulation results show that the proposed analysis and control method can effectively derive the characteristics and improve the motion performance, which provides the primary theoretical guide for the configuration design, optimization and control research of multi-DOF deflection type actuators.  相似文献   
104.
Automatic solution of vehicle operation adjustment is the important content in realizing vehicle traffic command automation on Internet of Things platform. Based on both the organization realization of Internet of Things platform and the merging vehicle operation adjustment into the Flow-Shop scheduling problem in manufacturing systems, this paper has constructed the optimization model with a two-lane vehicle operation adjustment. With respect to the large model solution space and complex constraints, a better solution algorithm is proposed based on ant colony algorithm for optimal quick solution. The simulation results show that the algorithm is feasible and the approximate optimal solution can be quickly obtained.  相似文献   
105.
Online social networking sites (OSNS), as a popular social media platform, have been developed massively for business and research purposes. In this paper, it investigated the impact of community structure in online social network on information propagation. A SI (Susceptible-Infected) model based on community structure was proposed. In the SI model, the heterogeneity of user’s active time was taken into account. From the results, it was found that the number of links among communities determines the fraction of infected nodes. With the increase of the number of groups G, however, the fraction of infected nodes remains approximately constant. The simulation results will be of great significance: the information will last relatively short for group networks which have either a small or a large number of groups. The results can be useful for optimizing or controlling information, such as propagating rumors in online social networks.  相似文献   
106.
The useful life of wooden pallets is lower because of the defects in lumbers. The quality of lumber can be significantly enhanced by heat treatment. In this paper, the larch pallet decks samples were heat-treated under the conditions of different time and temperatures. The quantity of water uptake has reduced 16.8% under the condition of 250 ℃ for 150 min. The resistance of water absorption efficiency increases 165.34% under the condition of 175 ℃ for 90 min. The anti-shrink efficiency increases 72.08% under the condition of 250 ℃ for 90min. The results showed that the dimension stability of larch panels can be improved by heat treatment. The condition of 250 ℃ for 180 min is the best heat treating condition to improve the dimension stability.  相似文献   
107.
在城市设计过程中,突出城市的个性化文化元素是必不可少的,城市文化的再生也已成为促进城市积极发展的主要方法之一。本文着眼于文化对城市发展的影响以及城市设计理论与文化再生之间的相互关系,分析了文化在城市发展过程中扮演的角色与所起的作用,城市的蓬勃发展离不开其文化属性的凸显,有助于特色文化城市的形成。  相似文献   
108.
中美规范公路混凝土桥梁设计的分析与比较   总被引:1,自引:0,他引:1  
由于重载汽车的增加以及目前桥梁的损坏状况日趋严重,为确保公路桥梁设计的安全使用,将中美两国公路桥梁混凝土规范的设计荷载及结构抗力计算进行比较,为我国公路桥梁设计提供参考。  相似文献   
109.
所谓的精神瘫痪,是指都柏林人在都柏林压抑的环境下所表现出来的麻木、沉闷、无助、空虚等精神状态,它表现在都柏林社会生活的各个方面,已经成为一种集体疾病,无法摆脱。本文从《都柏林人》这部系列作品中的几个故事入手,通过人物刻画、情节设置、道具采用等角度探讨了精神瘫痪主题在都柏林人宗教生活描写中的体现,从而能够更加透彻地理解这位文学大师的创作特点。  相似文献   
110.
提出了一种自顶向下、深度优先的概念格横向合并算法.首先研究了父子概念插入顺序对新生概念和更新概念的影响,并证明了概念插入和更新的相关定理.在此基础上,设计了一种递归插入概念的遍历顺序,能够大幅缩小概念比较的范围.实验和分析均表明,与其他概念格合并算法相比,该算法效率明显提高,适合概念格的合并运算.  相似文献   
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