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51.
Jin  Rong  Zeng  Kai  Jiang  Chuan 《Wireless Networks》2022,28(6):2437-2453
Wireless Networks - Friendly spectrum jamming is a flexible scheme to establish secure communications among heterogeneous wireless devices without the need of encryption. Previous works have...  相似文献   
52.
Zhang  Kai  Zheng  Jing  Wang  Ying-Ming 《Applied Intelligence》2022,52(13):15177-15192
Applied Intelligence - Heterogeneous multi-attribute case retrieval is a crucial step in generating emergency alternatives during the course of emergency decision making (EDM) by referring to...  相似文献   
53.
54.
Nowadays, heating cables are used as heat sources for heating pavements in practical engineering. However, there is a contradiction between the snow melting function and the interlaminar stability of heating pavement. In order to solve the contradiction, the interlaminar failure behavior of asphalt mixture coupled heating cables specimen (AMCS) was researched, through experiments and the finite element method. Under the different conditions of heating cables and rolling times, a series of direct shear tests was performed at the interface of AMCS, to compare the interlaminar stability of three different AMCS. Meanwhile, based on the bilinear cohesive zone model and coulomb friction model a 2D finite element model was established, to simulate this shear failure processes and make up for the limitations of the experiment. According to above test and simulation results, the failure mechanism and the weakest interface in AMCS were found, and the influence of the heating cable’s diameter and embedded spacing on the interlaminar shear strength were found. Then, a modified coulomb theorem model was proposed to predict the shear strength of the AMCS. This research enriches the design theory of the heating pavement and it has great significance for its structural design of heating asphalt pavement.  相似文献   
55.
Laux S  Richter W 《Applied optics》1996,35(1):97-101
Optical thin films of MgF(2) and NdF(3) have been made by molecular-beam deposition in ultrahigh vacuum. The film packing density was calculated from the water amount that filled the cavities of the films in air. For that the transmission in the IR spectral region with a characteristic water absorption band at a wave number of 3400 cm(-1) was measured. The influence on the packing density of a modification of thin-film morphology by stratification of very thin sublayers of different crystallizing fluorides is tested.  相似文献   
56.
Laux S  Mann K  Granitza B  Kaiser U  Richter W 《Applied optics》1996,35(31):6216-6218
We have developed fluoride antireflection (AR) coatings on MgF(2) substrates for a wavelength of 248 nm by molecular-beam deposition. Transmission and laser-induced damage threshold of the samples were measured and atomic force microscope (AFM) investigations were carried out. We compare a 14-layer design for AR coatings with sublayer thicknesses of 12 nm with a conventional two-layer design with quarter-wavelength thicknesses. The laser-induced damage threshold of the 14-layer coating is slightly higher than that of the two-layer coating. The AFM surface images show that the 14-layer coating has a smoother surface than the two-layer coating.  相似文献   
57.
离心输油泵是石油化工产品输送的主要设备,微机在线监控系统主要用于炼油厂、乙烯厂、油库、输油管道等油气输送领域离心输油泵运行状态的监测、控制以及检修的预报等。本设计采用操作指导控制系统以及工厂的分布式层次化结构思想,以离心输油泵输入输出轴的振动参数为主要测试参数,并辅以离心输油泵油温、轴瓦温度监测,同时采用ADAM4000智能模块和RS—485网络,通过监控控制仪转换成RS—232信号给计算机,实现所需参数的显示与控制和计算机对离心输油泵的快速启停控制。系统软件基于Windows XP平台,运用北京亚控组态王6.5版开发而成,具有实用、实时、可靠与友好等特点。  相似文献   
58.
In this paper, we introduce the fuzzy model of the makespan on a single batch-processing machine with non-identical job sizes. The uncertainty of the jobs and the machine in the processing is denoted using fuzzy logic. Then an improved ant colony optimization (ACO) method is proposed and the Metropolis criterion is used to select the paths of ants to overcome the immature convergence of the algorithm. In the experiment, we adopt the random instances and the results of the fuzzy makespan demonstrate that the proposed algorithm outperforms GA and SA in all instances.  相似文献   
59.
Surgery to reshape the nose with an implant has been a regular procedure for enhancing a patient’s appearance and self-confidence. The purpose of this study was to establish a computed tomography (CT) based three-dimensional assistant plastic surgery systems, which can provide the patients with realistic prediction of their own postoperative appearance in computer and specifically produce a nose implant for an individual patient. Preoperative CT data and 3D reconstruction techniques were employed to generate 3D model of the patient’s skull. 3D collision detection and finite elements model deformation were then applied to simulate nose augmentation surgery and predict postoperative appearance. According to the patient’s expectation, digital models of the nose implants were constantly modified. When the patient is satisfied with the simulated results, custom made silicone implants were produced by a computer controlled device. Accurately regeneration of 3D images and realistic operative simulations could be achieved with this system. The implants produced exactly conformed to the results of simulation. No curving and reshaping were needed during operating. The clinical results extremely matched with the simulations. The system enhances surgeon patient communication and facilitates preoperative planning. It is especially desirable for implant surgery with less guesswork of size, contour, and orientation of the implant. The best chance of optimal results could be achieved.  相似文献   
60.
针对以单片机为核心的风机性能测试系统存在稳定性差、抗干扰能力差、精度低等问题,开发了以PLC为核心、采用互感式采集模块EDA9033A采集风机电参数的分布式风机性能测试系统,给出了该风机性能测试系统的结构,详细介绍了EDA9033A的硬件及软件设计。实际应用表明,EDA9033A采集的风机电参数结果稳定、快速、准确。  相似文献   
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