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991.
Our research explores a virtual reality application based on Web camera (Webcam) input-interface. The interface can replace with the mouse to control direction intention of a user by the method of frame difference. We divide a frame into nine grids from Webcam and make use of the background registration to compute the moving object. In order to make this technology apply to 3D virtual reality system, we use the Virtools Dev to build virtual scenes and the Microsoft Visual C++ to build this interface. We also use the MySQL database management system to access users’ data and the displaying data. We implement a number of Building Blocks (BB) to support Virtools Dev for using the database management system and the Webcam input-interface in this composite system. The results of research are expected to the digital content industries such that users can easy to use the input-interface to control browsing the virtual reality. Our system can supply interactive digital content, photographs, and access the questions from the database management system. In addition, the system provides the browsing mold, the question mold, and the course content describing mold with the input-interface. In order to explore the intention of users for using the system, we design the questionnaire based on the technology acceptance model (TAM). In our empirical study, we find that perceived playfulness is positive association with attitude toward using. Interface style is positive association with perceived ease of use. 相似文献
992.
The popularity of video games has transcended entertainment crossing into the world of education. While the literature base on educational gaming is growing, there is still a lack of systematic study of this emerging technology’s efficacy. This quasi-experimental study evaluated a teacher created video game on genetics in terms of its affective and cognitive impact on student users. While statistical results indicated no differences (p > .05) in student learning as measured by our instrument, there were significant differences (p < .05) found in the participants’ level of engagement while interfacing with the video game. Implications on this emerging line of inquiry are discussed. 相似文献
993.
994.
Given a real number sequence A=(a1,a2,…,an), an average lower bound L, and an average upper bound U, the Average-Constrained Maximum-Sum Segment problem is to locate a segment A(i,j)=(ai,ai+1,…,aj) that maximizes ∑i?k?jak subject to . In this paper, we give an O(n)-time algorithm for the case where the average upper bound is ineffective, i.e., U=∞. On the other hand, we prove that the time complexity of the problem with an effective average upper bound is Ω(nlogn) even if the average lower bound is ineffective, i.e., L=−∞. 相似文献
995.
Scheduling with learning effects has attracted growing attention of the scheduling research community. A recent survey classifies the learning models in scheduling into two types, namely position-based learning and sum-of-processing-times-based learning. However, the actual processing time of a given job drops to zero precipitously as the number of jobs increases in the first model and when the normal job processing times are large in the second model. Motivated by this observation, we propose a new learning model where the actual job processing time is a function of the sum of the logarithm of the processing times of the jobs already processed. The use of the logarithm function is to model the phenomenon that learning as a human activity is subject to the law of diminishing return. Under the proposed learning model, we show that the scheduling problems to minimize the makespan and total completion time can be solved in polynomial time. We further show that the problems to minimize the maximum lateness, maximum tardiness, weighted sum of completion times and total tardiness have polynomial-time solutions under some agreeable conditions on the problem parameters. 相似文献
996.
Yingda Cheng Irene M. Gamba Armando Majorana Chi-Wang Shu 《Computer Methods in Applied Mechanics and Engineering》2009,198(37-40):3130-3150
In this paper, we present results of a discontinuous Galerkin (DG) scheme applied to deterministic computations of the transients for the Boltzmann–Poisson system describing electron transport in semiconductor devices. The collisional term models optical-phonon interactions which become dominant under strong energetic conditions corresponding to nano-scale active regions under applied bias. The proposed numerical technique is a finite element method using discontinuous piecewise polynomials as basis functions on unstructured meshes. It is applied to simulate hot electron transport in bulk silicon, in a silicon n+–n–n+ diode and in a double gated 12 nm MOSFET. Additionally, the obtained results are compared to those of a high order WENO scheme simulation and DSMC (Discrete Simulation Monte Carlo) solvers. 相似文献
997.
998.
Margin based feature extraction has become a hot topic in machine learning and pattern recognition. In this paper, we present
a novel feature extraction method called Adaptive Margin Maximization (AMM) in which margin is defined to measure the discrimination
ability of the features. The motivation comes principally from the iterative weight modification mechanism of the powerful
boosting algorithms. In our AMM, the samples are dynamically weighted and features are learned sequentially. After one new
feature is learned by maximizing the weighted total margin of data, the weights are updated so that the samples with smaller
margins receive larger weights. The feature learned in the next round will thus try to concentrate more on these “hard” samples
adaptively. We show that when the data are projected onto the feature space learned by AMM, most examples have large margins,
and therefore the nearest neighbor classifier yields small generalization error. This is in contrast to existing margin maximization
based feature extraction approaches, in which the goal is to maximize the total margin. Extensive experimental results on
benchmark datasets demonstrate the effectiveness of our method. 相似文献
999.
Adaptive binary tree for fast SVM multiclass classification 总被引:1,自引:0,他引:1
This paper presents an adaptive binary tree (ABT) to reduce the test computational complexity of multiclass support vector machine (SVM). It achieves a fast classification by: (1) reducing the number of binary SVMs for one classification by using separating planes of some binary SVMs to discriminate other binary problems; (2) selecting the binary SVMs with the fewest average number of support vectors (SVs). The average number of SVs is proposed to denote the computational complexity to exclude one class. Compared with five well-known methods, experiments on many benchmark data sets demonstrate our method can speed up the test phase while remain the high accuracy of SVMs. 相似文献
1000.
This study presents a novel plastic package for piezoresistive pressure sensors. A photoresist dam-ring patterned using the lithographic process is spin-coated on a piezoresistive pressure sensor to define a sensing channel in the pressure sensor package. Fluid epoxy molding encapsulates the pressure sensor and exposes the sensing channel during a high-temperature molding process at 165 °C. Experimental observations reveal that the silicon membrane of the pressure sensor is completely free of epoxy molding compound (EMC) contamination after the transfer molding process. The effectiveness of the dam-ring in shielding the silicon membrane of the pressure sensor during the molding process was confirmed. The packaged pressure sensor exerts a thermo-mechanical stress on the silicon membrane of the pressure sensor, resulting in an undesired output voltage drift. However, employing a package design with a large sensing channel opening can reduce the effect of package-induced stress. The proposed packaging scheme was a small package volume and surface-mount device (SMD) compatible features, making it suitable for portable commercial devices. 相似文献