浅谈市政道路工程施工过程的质量控制

以广州某市政道路工程为例 ,对路基土石方工程和路面工程的施工工艺流程及施工要点作了介绍 ,提出了相应的质量控制措施 ,对市政道路工程的施工具有一定的借鉴意义     

ND-A型核子土基密度计的研制

本文介绍研制的ND-A型核子土基密度计。这是一种用来测量土基湿密度的快速、非破坏性、精确的测量仪器,测量误差为±1％。     

具耗散项弹性力学方程组弱解存在性

利用粘性消失法和补偿紧致理论证明具耗散项弹性力学方程组弱解的存在性．     

Edge based features for content based image retrieval

The common problem in content based image retrieval (CBIR) is selection of features. Image characterization with lesser number of features involving lower computational cost is always desirable. Edge is a strong feature for characterizing an image. This paper presents a robust technique for extracting edge map of an image which is followed by computation of global feature (like fuzzy compactness) using gray level as well as shape information of the edge map. Unlike other existing techniques it does not require pre segmentation for the computation of features. This algorithm is also computationally attractive as it computes different features with limited number of selected pixels.     

Worst-case identification in Banach spaces

A general formulation of worst-case identification of linear systems in a Banach space framework is discussed. This enables one to prove generalizations of various existence theorems from the theory of robust ℓ₁ and H_∞ identification to a variety of other situations.     

lp空间紧性的研究

利用profile分解技术,研究lp(1≤p<+∞)空间的紧性。讨论了导致紧性失去的两种情形,给出了lp空间中有界序列的分解。主要的困难在于profile的提取,利用排除集中的方法克服了这一困难,并在较弱的拓扑中得到了余项的衰减。     

Left‐handed meta‐surface loaded with ring resonator modelling for satellite application

A new geometry of compact meta‐surface, loaded with the ring resonator for satellite application (Ku‐band), is presented in this paper. The diamond‐shaped meta‐surface is designed by the metallic ring resonator with metallic ground plane separated by a dielectric substrate layer, while epoxy resin fibre is utilized as a dielectric substrate layer. The proposed meta‐surface structure is successfully simulated, fabricated, and measured. Effects of the design specifications on the surface current and field distribution are also investigated elaborately. Theoretical and simulated results show that the diamond‐shape structure resonance is at 15.84 GHz, whereas the measured results are slightly shifted around at 15.87 GHz. The designed meta‐surface structure also exhibits the left‐handed characteristics at 15.88 GHz, where the estimations of permittivity is ?4 + 0.28j, permeability is ?19.2 ? 134.6j, and negative index is ?5.51 ? 3.86j. Further, the lumped element equivalent circuit model of the proposed meta‐surface unit cell is explained. Moreover, the 10 × 10 mm² meta‐surface single‐unit‐cell prototype is compact in size and the impact on the performance by modifying the meta‐surface structure is investigated. Therefore, the meta‐surface integrated antenna shows resonance frequency bands from 14.0 to 14.50 GHz, which is used as INSAT‐4A communication satellite uplink frequency.     

由正则子半群所决定的半群上子半群格的结构

本文中提出了半群上的正则子半群的概念,通过半群上的正则子半群给出了半群上的一般子半群的表示,进而研究了半群上的子半群格成为完全分配格的几个充要条件。同时,对比正则性更为广义的紧致性也作了一般探讨。