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31.
Since a large variety of digital games have been used in many fields for educational purposes, their real functions in learning have caught much attention as well. This study first defines learning characteristics of problem-solving digital games and their corresponding cognitive levels, then designs and develops a problem-solving game in accordance to the criteria. Tasks in the game context are inter-related to each other so that players need to critically and creatively think about problem solutions. Learners’ task analyses are performed to observe four elementary learners’ gaming paths, behaviors and cognitive activities, individually and collaboratively. System documentation, video recording, researcher observation, and interviews are conducted to analyze learners’ learning strategies and their cognitive performance during the gaming process. 相似文献
32.
Wen-Bin Lin Huann-Keng Chiang Kuang-Rong Shih Chien-An Chen 《Artificial Life and Robotics》2010,15(4):473-477
This article proposes the PC-based LabVIEW as the software to develop the algorithm of the robust complex extended Kalman
filter (RCEKF) to detect the parameters of the voltage signal in power systems. The hardware used is a sample-and-hold card
and a data acquisition (DAQ) card to extract the data from an outside system to the PC, and the program will compute the amplitude,
frequency, and phase of the voltage signal with RCEKF. To validate the performance of RCEKF, the voltage signal from a function
generator was applied to check the feasibility of the algorithm. This application was also used in the Taiwan Power Company
(TPC) secondary substation in Sijhou, Taiwan. 相似文献
33.
Han M. Shih 《Computers & Industrial Engineering》2011,61(3):608-628
In geometry, two configurations are called similar if they can be brought to a complete match by rigid motions and dilations. In the simplest case, product designs X and Y have the same dimensionality and same number of points which can be brought into a one to one correspondence by substantive considerations. Under orthogonal transformations, product design Y can only be rotated and reflected in order to approximate product design X. As for the “as close as possible” or “relatively close” criterion, a reasonable definition would be to measure the distances between corresponding points, square these values, and add them to obtain the sum-of-squares criterion L. In this paper, a product structure (BOM)-based product similarity measures using orthogonal procrustes approach is proposed. A structural product is first transformed into bill of materials (BOM), the structural similarity measurement between a product query and target product is calculated and evaluated using orthogonal procrustes approach. The results show that the proposed product structure similarity measure method can help companies find desired product information based on BOM feature. 相似文献
34.
We have investigated real-time, label-free, in-situ detection of human epidermal growth factor receptor 2 (Her2) in diluted serum using the first longitudinal extension mode of a lead zirconate-lead titanate (PZT)/glass piezoelectric microcantilever sensor (PEMS) with H3 single-chain variable fragment (scFv) immobilized on the 3-mercaptopropyltrimethoxysilane (MPS) insulation layer of the PEMS surface. We showed that with the longitudinal extension mode, the PZT/glass PEMS consisting of a 1 mm long and 127 μm thick PZT layer bonded with a 75 μm thick glass layer with a 1.8 mm long glass tip could detect Her2 at a concentration of 6-60 ng/ml (or 0.06-0.6 nM) in diluted human serum, about 100 times lower than the concentration limit obtained using the lower-frequency flexural mode of a similar PZT/glass PEMS. We further showed that with the longitudinal mode, the PZT/glass PEMS determined the equilibrium H3-Her2 dissociation constant K(d) to be 3.3±0.3 × 10(-8) M consistent with the value, 3.2±0.28 ×10(-8) M deduced by the surface plasmon resonance method (BIAcore). 相似文献
35.
Feehrer John Rotker Paul Shih Milton Gingras Paul Yakutis Peter Phillips Stephen Heath John 《Micro, IEEE》2009,29(4):36-47
CoHub, a coherency hub ASIC, provides a cost-effective way to extend a glueless two-node chip-multithreading system to a four-node system without changes to the processor. The four-node, 256-thread system achieves near-linear scaling of performance with thread count on transaction-processing workloads. Time-to-market pressure, 800-MHz operation, and a six-stage pipeline were among the constraints that shaped CoHub's design. 相似文献
36.
Remote user authentication scheme is a procedure which allows a server to authenticate a remote user through insecure channel. Recently, Yoon, Ryu and Yoo made an enhancement based on Ku–Chen’s remote user authentication scheme by using smart cards. The scheme has the merits of providing mutual authentication, no verification table, freely choosing password, involving only few hashing operations and parallel session attack resistance. In this paper, we point out security flaws of Yoon–Ryu–Yoo’s protocols against masquerading attack, off-line password guessing attacks and parallel session attack. An improvement to enhance Yoon–Ryu–Yoo’s security scheme is proposed. 相似文献
37.
Chiang Lee Chi-Sheng Shih Yaw-Huei Chen 《The VLDB Journal The International Journal on Very Large Data Bases》2001,9(4):327-343
Traditional algorithms for optimizing the execution order of joins are no more valid when selections and projections involve
methods and become very expensive operations. Selections and projections could be even more costly than joins such that they
are pulled above joins, rather than pushed down in a query tree. In this paper, we take a fundamental look at how to approach
query optimization from a top-down design perspective, rather than trying to force one model to fit into another. We present
a graph model which is designed to characterize execution plans. Each edge and each vertex of the graph is assigned a weight
to model execution plans. We also design algorithms that use these weights to optimize the execution order of operations.
A cost model of these algorithms is developed. Experiments are conducted on the basis of this cost model. The results show
that our algorithms are superior to similar work proposed in the literature.
Received 20 April 1999 / Accepted 9 August 2000 Published online 20 April 2001 相似文献
38.
Shih Hao Huang Hwa Seng Khoo Shang Yu ChangChien Fan Gang Tseng 《Microfluidics and nanofluidics》2008,5(4):459-468
Monodisperse copolymer particles carrying surface carboxyl groups in the range of 50–200 μm were prepared by in situ UV polymerization
of ethyleneglycol dimethacrylate (EGDMA) with acrylic acid (AA) via a microfluidic flow-focusing device (MFFD). The design
of the coaxial orifices in the MFFD enables the confinement of the comonomer liquid thread to the central axis of the microchannel,
which can avoid the wetting problem of comonomer liquid with the microchannel and can successfully produce monodisperse copolymer
microspheres with coefficient of variance below 5%. The effects of concentration of EGDMA and AA on droplet diameters and
the distribution of carboxyl group on particle surfaces were examined. It has been found that, increasing the concentration
of AA would decrease particle sizes, but increase the distribution of carboxyl group on particle surfaces. Bioconjugation
of the carboxylated copolymer particles with the anti-rabbit IgG–Cy3 conjugates was successfully demonstrated. By increasing
the concentration of AA accompanied with decreasing the particle sizes, high efficiency of bioconjugation on carboxylated
copolymer particles was achieved. The rapid continuous synthesis of carboxylated copolymer particles via a microfluidic device
provides a reliable control of particle sizes and composition for massive production in biotechnological applications. 相似文献
39.
Chao-Tung Yang Po-Chi Shih Cheng-Fang Lin Sung-Yi Chen 《The Journal of supercomputing》2007,40(3):249-267
This paper describes a resource broker whose main function is to match available resources to user needs. The resource broker
provides a uniform interface for accessing available and appropriate resources via user credentials. We also focus on providing
approximate measurement models for network-related information using NWS for future scheduling and benchmarking. We first
propose a network measurement model for gathering network-related information (including bandwidth, latency, forecasting,
error rates, etc.) without generating excessive system overhead. Second, we constructed a grid platform using Globus Toolkit
that integrates the resources of five schools in Taichung integrated grid environment resources (TIGER). The resource broker
runs on top of TIGER. Therefore, it provides security and current information about available resources and serves as a link
to the diverse systems available in the Grid.
相似文献
Sung-Yi ChenEmail: |
40.
Yu-Chuan Shih Chung-Yu Wu 《IEEE sensors journal》2005,5(5):956-963
In this paper, a pixel structure called the optimal pseudoactive pixel sensor (OPAPS) is proposed and analyzed for the applications of CMOS imagers. The shared zero-biased-buffer in the pixel is used to suppress both dark current of photodiode and leakage current of pixel switches by keeping both biases of photodiode and parasitic pn junctions in the pixel bus at zero voltage or near zero voltage. The factor of photocurrent-to-dark-current ratio per pixel area (PDRPA) is defined to characterize the performance of the OPAPS structure. It is found that a zero-biased-buffer shared by four pixels can achieve the highest PDRPA. In addition, the column sampling circuits and output correlated double sampling circuits are also used to suppress fixed-pattern noise, clock feedthrough noise, and channel charge injection. An experimental chip of the proposed OPAPS CMOS imager with the format of 352/spl times/288 (CIF) has been designed and fabricated by using 0.25-/spl mu/m single-poly-five-level-metal (1P5M) N-well CMOS process. In the fabricated CMOS imager, one shared zero-biased-buffer is used for four pixels where the PDRPA is equal to 47.29 /spl mu/m/sup -2/. The fabricated OPAPS CMOS imager has a pixel size of 8.2/spl times/.2 /spl mu/m, fill factor of 42%, and chip size of 3630/spl times/3390 /spl mu/m. Moreover, the measured maximum frame rate is 30 frames/s and the dark current is 82 pA/cm/sup 2/. Additionally, the measured optical dynamic range is 65 dB. It is found that the proposed OPAPS structure has lower dark current and higher optical dynamic range as compared with the active pixel sensor (APS) and the conventional passive pixel sensor (PPS). Thus, the proposed OPAPS structure has high potential for the applications of high-quality and large-array-size CMOS imagers. 相似文献