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101.
The holmium-doped calcium fluoride (Ho:CaF(2)) crystal was shown to be an effective solid-state saturable-absorber Q-switch for a flash-lamp-pumped Tm,Cr:Y(3)Al(5)O(12) laser at 2.017 μm. With a 1-cm-thick Ho(0.5%),Er(5%):CaP(2) saturable absorber and a 6.3% output coupler, a single Q-switched laser pulse of 51 mJ in energy and 60 ns in duration was obtained at a flash-lamp input energy of 85 J. With a 14.6% output coupler, a typical Q-switched laser pulse of 84 mJ and 82 ns was observed. 相似文献
102.
由于雷达数据处理的要求,需要对雷达数据进行实时地存储记录。本文介绍了一种基于光纤通道的高速数据采集系统,以FPGA为平台,PCIExpress为接口,链式DMA为传输模式,实现了最高速率为6Gbps的数据采集系统。 相似文献
103.
Chung-Ming Kuo Wei-Han Chang Min-Yuan Fang Ching-Hsuan Lin 《Multimedia Tools and Applications》2011,55(3):399-422
In this paper, we present an effective and efficient framework for baseball video scene classification. The results of scene
classification can be able to provide the ground for baseball video abstraction and high-level event extraction. In general,
most conventional approaches are shot-based, which shot change detection and key-frame extraction are necessary prerequisite
procedures. On the contrary, we propose a frame-based approach. In our scene classification framework, an efficient playfield
segmentation technique is proposed, and then the reduced field maps are utilized as scene templates. Because the shot change
detection and the key-frame extraction are not required in proposed method, the new framework is very simple and efficient.
The experimental results have demonstrated that the effectiveness of our proposed framework for baseball videos scene classification,
and it can be easily extended the template-based approach to other kinds of sports videos. 相似文献
104.
Assembly line design is an important part of production system. Some processes need to undergo changes in order to increase in efficiency. Computer simulation has been applied on process design for many decades. Traditionally, simulation had to run all possible alternatives of assembly line and was not considered as an optimization technique. Thus, this study employs particle swarm optimization (PSO) algorithm which is with mutation based on similarity for simulation optimization in order to optimize the managerial parameters in production system. Through experimentation designs and statistics tests, the simulation results show that the proposed method is better than other algorithms, like genetic algorithm and conventional PSO algorithm for solving assembly line design problem. 相似文献
105.
Michael McAleer Bing-Wen Huang Hsiao-I. Kuo Chi-Chung Chen Chia-Lin Chang 《Environmental Modelling & Software》2010,25(1):100-106
This paper compares the impacts of SARS and human deaths arising from Avian Flu on international tourist arrivals to Asia. The effects of SARS and human deaths from Avian Flu are compared directly according to the number of human deaths. The nature of the short run and long run relationship is examined empirically by estimating a static line fixed effect model and a difference transformation dynamic model, respectively. Empirical results from the static fixed effect and difference transformation dynamic models are consistent, and indicate that both the short run and long run SARS effect have a more significant impact on international tourist arrivals than does Avian Flu. In addition, the effects of deaths arising from both SARS and Avian Flu suggest that SARS is more important to international tourist arrivals than is Avian Flu. Thus, while Avian Flu is here to stay, its effect is currently not as significant as that of SARS. 相似文献
106.
Chien-Pang Lee Wen-Shin Lin Yuh-Min Chen Bo-Jein Kuo 《Expert systems with applications》2011,38(5):4661-4667
Recently, microarray technology has widely used on the study of gene expression in cancer diagnosis. The main distinguishing feature of microarray technology is that can measure thousands of genes at the same time. In the past, researchers always used parametric statistical methods to find the significant genes. However, microarray data often cannot obey some of the assumptions of parametric statistical methods, or type I error may be over expanded. Therefore, our aim is to establish a gene selection method without assumption restriction to reduce the dimension of the data set. In our study, adaptive genetic algorithm/k-nearest neighbor (AGA/KNN) was used to evolve gene subsets. We find that AGA/KNN can reduce the dimension of the data set, and all test samples can be classified correctly. In addition, the accuracy of AGA/KNN is higher than that of GA/KNN, and it only takes half the CPU time of GA/KNN. After using the proposed method, biologists can identify the relevant genes efficiently from the sub-gene set and classify the test samples correctly. 相似文献
107.
This study applies energy method to derive the system modeling of a triaxial microaccelerometer that consists of a quadri-beam
suspension, a seismic mass, and displacement transducers using piezoelectric thin films. Two suspension beams support both
ends of the seismic mass, which is fabricated by anisotropic etching of silicon. An out-of-plane acceleration will result
in a symmetric bend, and in-plane accelerations will produce asymmetric bend and torsion of the suspension beams. Two piezoelectric
thin-film transducers are arranged at both ends of each suspension beam. Eight transducers in total are interconnected such
that triaxial accelerations can be measured selectively. The structure stiffness of the suspension beams considers both the
silicon beams and piezoelectric films by the use of the laminated beam theory. Therefore, the analytical model is applicable
to the accelerometers with thick piezoelectric films. The model is based on the anisotropic material properties of Silicon
and PZT and Euler’s beam equation with the assumptions that smaller strains and stresses are negligible. The analytical results
of the resonant frequencies and sensor sensitivities to triaxial accelerations are presented and confirmed by finite element
analysis. 相似文献
108.
In this study, an adaptive fuzzy time series model for forecasting Taiwan’s tourism demand is proposed to further enhance the predicted accuracy. We first transfer fuzzy time series data to the fuzzy logic group, assign weights to each period, and then use the proposed adaptive fuzzy time series model for forecasting in which an enrollment forecasting values is applied to obtain the smallest forecasting error. Finally, an illustrated example for forecasting Taiwan’s tourism demand is used to verify the effectiveness of proposed model and confirmed the potential benefits of the proposed approach with a very small forecasting error MAPE and RMSE. 相似文献
109.
Zhe Fan Yu-Chuan Kuo Ye Zhao Feng Qiu Arie Kaufman William Arcieri 《The Visual computer》2009,25(11):985-996
We present a simulation and visualization system for a critical application—analysis of the thermal fluid dynamics inside
a pressurized water reactor of a nuclear power plant when cold water is injected into the reactor vessel. We employ a hybrid
thermal lattice Boltzmann method (HTLBM), which has the advantages of ease of parallelization and ease of handling complex
simulation boundaries. For efficient computation and storage of the irregular-shaped simulation domain, we classify the domain
into nonempty and empty cells and apply a novel packing technique to organize the nonempty cells. This method is implemented
on a GPU cluster for acceleration. We demonstrate the formation of cold-water plumes in the reactor vessel. A set of interactive
visualization tools, such as side-view slices, 3D volume rendering, thermal layers rendering, and panorama rendering, are
provided to collectively visualize the structure and dynamics of the temperature field in the vessel. To the best of our knowledge,
this is the first system that combines 3D simulation and visualization for analyzing thermal shock risk in a pressurized water
reactor. 相似文献
110.
Intelligent building can provide safety, convenience, efficiency and entertainment for life in the 21st century. The most importance role of the intelligent building is the security system. We develop a multi sensor-based intelligent security robot (ISR) that is widely employed in intelligent buildings. The intelligent security robot can detect abnormal and dangerous situations and notify users. The robot has the shape of cylinder and its diameter, height, and weight are 50 cm, 130 cm and 100 kg respectively. The function of the ISR contains six parts. There is the software development system; avoiding obstacle and motion planning system, image system, sensor system, remote supervise system and other systems. We develop a multi sensor-based sensor system in the ISR. We use multiple multisensor fusion algorithms to get an exact decision in the detection subsystem of the sensor system. There is an adaptive fusion method, a rule based method, and a statistical signal method. We demonstrate the remote supervisory system to control the ISR using a direct control mode and a behavior control mode. We think that the man–machine interface in a security robot system must have mobility and convenience. Therefore, we use a touch screen to display the system state, and design a general user interface (GUI) to service the user and visitors. The user can remotely control the appliance using a cell phone through a GSM modem, too. The appliance module can feedback reaction results to the user through a cell phone. Finally, we implement the fire detection system in the intelligent security robot (Chung-Cheng-I). If a fire occurs, the intelligent security robot can find out the fire source using the fire detection system. In intruder detection, we program the same scenario to detect the intruder using the intelligent security robot. The intelligent security robot transmits the message of the detection result to the user using a GSM modem for a fire event or intruder, and transmits the detection result to a client computer through the internet. 相似文献