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81.
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
82.
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
83.
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
84.
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
85.
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
86.
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
87.
Jorng-Tzong Horng Li-Cheng Wu Baw-Juine Liu Jun-Li Kuo Wen-Horng Kuo Jin-Jian Zhang 《Expert systems with applications》2009,36(5):9072-9081
Gene selection can help the analysis of microarray gene expression data. However, it is very difficult to obtain a satisfactory classification result by machine learning techniques because of both the curse-of-dimensionality problem and the over-fitting problem. That is, the dimensions of the features are too large but the samples are too few. In this study, we designed an approach that attempts to avoid these two problems and then used it to select a small set of significant biomarker genes for diagnosis. Finally, we attempted to use these markers for the classification of cancer. This approach was tested the approach on a number of microarray datasets in order to demonstrate that it performs well and is both useful and reliable. 相似文献
88.
Control chart patterns (CCPs) are widely used to identify the potential process problems in modern manufacturing industries.
The earliest statistical techniques, including chart and R chart, are respectively used for monitoring process mean and process variance. Recently, pattern recognition techniques based
on artificial neural network (ANN) are very popular to be applied to recognize unnatural CCPs. However, most of them are limited
to recognize simple CCPs arising from single type of unnatural variation. In other words, they are incapable to handle the
problem of concurrent CCPs where two types of unnatural variation exist together within the manufacturing process. To facilitate
the research gap, this paper presents a hybrid approach based on independent component analysis (ICA) and decision tree (DT)
to identify concurrent CCPs. Without loss of generality, six types of concurrent CCPs are used to validate the proposed method.
Experimental results show that the proposed approach is very successful to handle most of the concurrent CCPs. The proposed
method has two limitations in real application: it needs at least two concurrent CCPs to reconstruct their source patterns
and it may be incapable to handle the concurrent pattern incurred by two correlated process (“upward trend” and “upward shift”). 相似文献
89.
Te-Hsiu Sun Fang-Cheng Tien Fang-Chih Tien Ren-Jieh Kuo 《Journal of Intelligent Manufacturing》2016,27(3):639-651
Machine vision is an excellent tool for inspecting a variety of items such as textiles, fruit, printed circuit boards, electrical components, labels, integrated circuits, machine tools, etc. This paper presents an intelligent system that incorporates machine vision with artificial intelligent networks to automatically inspect thermal fuses. An effective inspection flow is proposed to detect four commonly seen defects, including black-dot, small-head, bur, and flake during the production of thermal fuses. Backpropagation neural networks and learning vector quantization performance is compared in detecting the bur defect because of its illegibility. Different numbers of defective samples were screened out from a production line in a case study company and used to demonstrate the efficacy of the proposed system. Currently, the proposed inspection system is operating at the case study company, replacing four to six human inspectors. The system not only ensures the quality of the thermal fuses produced, but also reduced the cost of manual visual inspection. 相似文献
90.
Kun-Lin Kuo 《Computational statistics & data analysis》2011,55(8):2457-2462
A distribution is said to be conditionally specified when only its conditional distributions are known or available. The very first issue is always compatibility: does there exist a joint distribution capable of reproducing all of the conditional distributions? We review five methods-mostly for two or three variables-published since 2002, and we conclude that these methods are either mathematically too involved and/or are too difficult (and in many cases impossible) to generalize to a high dimension. The purpose of this paper is to propose a general algorithm that can efficiently verify compatibility in a straightforward fashion. Our method is intuitively simple and general enough to deal with any full-conditional specifications. Furthermore, we illustrate the phenomenon that two theoretically equivalent conditional models can be different in terms of compatibilities, or can result in different joint distributions. The implications of this phenomenon are also discussed. 相似文献