基于加速残差网络的图像超分辨率重建方法

针对深层网络架构的图像超分辨率重建任务中存在网络参数多、计算复杂度高等问题,提出了一种基于加速残差网络的图像超分辨率重建方法.首先,构建一个残差网络对低分辨率图像与高分辨率图像之间的高频残差信息进行重建,以减少冗余信息的深层网络传输过程,提高重建效率;然后,通过特征收缩层对提取的低分辨率特征图进行降维,从而以较少的网络...     

多次采动影响巷道高预应力桁架锚索支护技术

为解决多次采动下巷道围岩控制难题,采用理论分析、现场试验的方法,提出了高预应力桁架锚索支护系统原理,该系统设置的同轴式连接紧缩器对拉预紧,使顶板岩层处于形成多向挤压状态,有效改善巷道围岩应力环境,高预紧力、桁架结构、锚索良好的延伸率使其具有"先刚"、"先抗"、"后柔"、"后让"的支护特点,现场应用验证了技术参数的合理性...     

Superior reinforcement in polyamide 1010/multiwalled carbon nanotube composites realized by high‐rate drawing and incorporation of compatibilizer

To realize the full potential of carbon nanotubes (CNTs) in polymer/CNT nanocomposites, many complicated chemical treatments have been developed to modify the CNTs. Nevertheless, the reinforcing efficiency is still not satisfactory in most cases. In this study, a dramatically improved mechanical enhancement is obtained for polyamide 1010/multiwalled carbon nanotube (MWNT) composites simply by exerting high‐rate drawing and incorporating a commercially available compatibilizer. For the fibers prepared at high draw ratio, their tensile strength and modulus are improved by 137 and 132%, respectively, through adding only 0.5 wt% MWNTs. In particular, the increase in strength is at a very high level for the case of non‐covalent interaction since CNTs could be stretched to failure according to theoretical calculation. It is demonstrated that this reinforcement is mainly attributed to the compatibilizer inducing good dispersion, and the high‐rate drawing inducing strong interfacial interaction and orientation of MWNTs. Copyright © 2012 Society of Chemical Industry     

硅钢退火炉氮气冷却的碳套辊分析

阐述了传统硅钢退火炉无冷却碳套辊的缺点,并介绍和分析了通氮气冷却碳套辊的技术特点。     

Effects of halloysite in kaolin on the formation and properties of geopolymers

A kaolin containing 31 wt.% halloysite and a relatively pure kaolin were selected to study the effects of halloysite on the dissolution behavior of precursors and the formation of geopolymers. The Al and Si concentrations in the leached solutions were studied by inductively coupled plasma-optical emission spectrometry (ICP-OES). The reaction process of metakaolin–activator mixtures was monitored by isothermal conduction calorimetry (ICC) while the reaction products were examined by X-ray diffractometry (XRD), scanning electron microscopy (SEM) and mercury intrusion porosity (MIP). Results showed that the halloysite containing kaolin and its metakaolin possessed higher Si and Al dissolution rate than the purer kaolin and its metakaolin. When mixed with sodium silicate activator at 20 °C, the presence of halloysite in kaolin led to a higher geopolymerization rate of metakaolin as reflected by the heat evolution rate. The presence of halloysite improved the reactivity of metakaolin but did not change the geopolymerization pathway under 20 °C air curing and 80 °C steam curing conditions. The products from the two metakaolins had a similar XRD characteristic (i.e. a typically amorphous diffraction). Only a minor difference in the pore distribution and the porosity was found between those products from the two sources of metakaolins.     

近代街区的防火改造与城市发展获益——以日本东京为例

为了防范持续爆发的大火,明治时代的日本政府在东京的人口密集区,设置多条防火带,对沿线的房屋的墙壁屋顶进行防火改造,同时又进行区域屋顶防火改造。由于措施得力,防火改造的任务顺利完成,从而有效地遏制了大面积火灾的发生,也改变了东京的城市面貌。     

企业内部网络的构建

企业内部网络是一个庞大而复杂的系统。企业内部网络的组建多侧重于局域网的设计,对设备的选型、网络拓扑的设计以及实现拓扑的搭建也应该有足够的重视;同时完善网络的组建、服务器的选择及配置、Internet接入技术以及防火墙的使用等亦非常重要。     

Evolution of fabric during undrained cyclic loading

Abstract

Undrained cyclic triaxial tests are performed on specimens of Ottawa sand to study the evolution of fabric during undrained cyclic loading. Isotropic consolidation tests and triaxial drained compression or extension tests are conducted before or after cyclic loading to characterize the state of fabric indirectly. The effects of stress path, cyclic stress ratio, cyclic number, and initial fabric on fabric evolution during undrained cyclic loading are investigated.     

Distillation separation sequence optimization synthesis based on application of adaptive parallel tabu search

Abstract

Distillation separation sequences can be described as binary tree data structures, because of the analogous structures of distillation separation sequences and binary trees, and then by applying graph theory, the change mechanism of neighborhood separation points based on binary trees is built, correspondingly a kind of highly effective, evolutionary neighborhood structure is constructed. For the purpose of researching further tabu search algorithms, adaptive mechanisms and parallel techniques are introduced. That is, according to memory frequency information, the tabu length and the number of candidates are adaptively adjusted, and multitask parallel technology is realized through the arrangement of the search assignments. The example shows that adaptive parallel tabu searches can solve, successfully, large‐scale distillation separation sequence synthesis problems.     

Solid state reaction synthesis and photoluminescence properties of Dy3+ doped NaGd(MoO4)2 phosphor

Dy³⁺ doped NaGd(MoO₄)₂ phosphors were synthesized by a traditional solid-state reaction route using NH₄HF₂ as a flux. The influence of calcination temperature on the crystal structure and spectral properties was studied, and the optimum calcination temperature for producing Dy³⁺ doped NaGd(MoO₄)₂ phosphor was experimentally confirmed. The concentration quenching of Dy³⁺ fluorescence and excitation-wavelength dependent spectroscopic properties were studied. On the base of both the Van Uitert's and I-H models, the electric dipole–dipole (D–D) interaction was ascribed to be the main physical mechanism responsible for energy transfer between Dy³⁺ ions. It was also discovered that the color coordinates of the Dy³⁺ doped NaGd(MoO₄)₂ phosphor depends on the Dy³⁺ doping concentration and the excitation wavelength.