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41.
Yong‐Kyu Jang Seong Jun Lee Jae Young Lee Yi Li Jae Hoon Hwang Sang Woo Kim Chang Woo Shim Ju Yeon Seo Nam Jin Kim Yi Joon Ahn Nam Hee Kim Seon Hong Ahn Seong Ryong Lee Dae Hee Park Chi Woo Kim 《Journal of the Society for Information Display》2011,19(3):253-257
Abstract— A novel pixel design for vertical‐alignment LCDs with superior transmittance has been developed. The new liquid‐crystal mode, refered to as the hole‐induced vertical‐alignment mode (Hi‐VA), uses a via hole of an organic layer on a TFT substrate to achieve multi‐domain alignment. Compared to the conventional design, the Hi‐VA mode has a transmittance of up to 135% with a contrast ratio of 2000:1. Moreover, the new structure is free from ITO patterning or protrusion on the color‐filter side, which makes the fabrication process simple and low cost. 相似文献
42.
Developing future weapons systems has become increasingly complicated and costly. The armed forces of major nations use modeling and simulation techniques for new weapons systems from the conceptual stage to design, production, deployment and training stages to shorten the development cycle and guarantee their effectiveness. Failure in the development cycle carries too much loss in time and money. Therefore, computer-based modeling and simulation techniques are applied from the conceptual stage to gauge the efficacy of new weapons systems. The objective of this study is to develop a modeling and simulation methodology for small scale engagement using the DEVS formalism. The entities required for modeling and simulation are divided into three categories: combat, logical, and environmental entities. Combat entities represent the military hardware or combatants; logical entities represent the judgment and decision entities for the interaction between various entities; and environmental entities emulate the constituents of real combat environment. The combat entities are further modeled into Shell and Core Parts to maximize their reusability under various combat scenarios. The proposed framework is verified using a one-on-one combat engagement simulation (written in C++) between two submarines. 相似文献
43.
Sang Min LeeAuthor VitaeJae Hwa SongAuthor Vitae Phill Gu JungAuthor VitaeDong Hyo JangAuthor Vitae Min Seong KimAuthor VitaeWeui Bong JeongAuthor Vitae Byung Min KimAuthor VitaeJong Soo KoAuthor Vitae 《Sensors and actuators. A, Physical》2011,171(2):233-240
A superhydrophobic micromesh covered with nanoprotrusions has been introduced and its applicability to a waterproof mobile phone speaker has been evaluated. The nanotextured superhydrophobic micromesh showed excellent water repellency, self-cleaning and waterproofing performances. In a waterproof speaker test using the fabricated nanotextured micromesh, the micromesh did not lose its waterproof function at 2 m water depth and did not form a remnant water film after being removed from the water. The packaged speaker showed almost the same sound quality before and after dipping at a 2 m water depth. These results demonstrate that the superhydrophobic nanotextured micromesh could be directly applicable for various products that need to resist water penetration, yet allow the transmission of gases and sound/light waves. 相似文献
44.
The interaction interface between two molecules can be represented as a bisector surface equidistant from the two sets of spheres of varying radii representing atoms. We recursively divide a box containing both sphere-sets into uniform pairs of sub-boxes. The distance from each new box to each sphere-set is conservatively approximated by an interval, and the number of sphere-box computations is greatly reduced by pre-partitioning each sphere-set using a kd-tree. The subdivision terminates at a specified resolution, creating a box partition (BP) tree. A piecewise linear approximation of the bisector surface is then obtained by traversing the leaves of the BP tree and connecting points equidistant from the sphere-sets. In 124 experiments with up to 16,728 spheres, a bisector surface with a resolution of 1/24 of the original bounding box was obtained in 28.8 ms on average. 相似文献
45.
A feature relies on three dimensions (space, theme, and time) for its representation. Even though spatiotemporal models have
been proposed, they have principally focused on the spatial changes of a feature. In this paper, a feature-based temporal
model is proposed to represent the changes of both space and theme independently. The proposed model modifies the ISO’s temporal
schema and adds new explicit temporal relationship structure that stores temporal topological relationship with the ISO’s
temporal primitives of a feature in order to keep track feature history. The explicit temporal relationship can enhance query
performance on feature history by removing topological comparison during query process. Further, a prototype system has been
developed to test a proposed feature-based temporal model by querying land parcel history in Athens, Georgia. The result of
temporal query on individual feature history shows the efficiency of the explicit temporal relationship structure.
相似文献
E. Lynn UseryEmail: |
46.
Optimization of 3.5-in. HDD spindle motors for OP-vibration performance: theoretical prediction and experimental verification 总被引:1,自引:1,他引:0
The purpose of this paper is to optimize OP-vibration performance of 3.5-in. hard disk drive (HDD) spindle motors through theoretical prediction and experimental verification. OP-vibration performance of HDD is closely related to the first rocking vibration of spindle motors because excited frequencies of 3.5-in. HDD from the environment are mostly below 500 Hz and the first rocking vibration is the only resonance in the corresponding frequencies. Therefore, minimizing first rocking vibration leads to improve OP-vibration performance of the spindle motors. In order to minimize the first rocking vibration key parameters of FDB spindle motors were selected from a previous work done by Heo and Shen (Microsyst Technol 11:1204–1213, 2005). Then, the selected parameters have been optimized to minimize the first rocking vibration through a theoretical model developed at University of Washington. Then, experiments with ten prototype FDB spindle motors have been conducted to verify the theoretical results. Each prototype motor has different spindle parameter configurations including bearing coefficients, bearing locations, and center of gravity location, etc. Also, this paper demonstrated that radial measurements of spindle rocking vibration have better correlation with OP-vibration performance than axial measurements through PES measurements. Finally, the optimized design has been manufactured by a motor maker and has also successfully verified the theoretical prediction experimentally. 相似文献
47.
Seong S. Chae Janice L. DuBien William D. Warde 《Computational statistics & data analysis》2006,50(12):3531-3546
Distributional and asymptotic results on the moment of Rand's Ck statistic were derived by DuBien and Warde [1981. Some distributional results concerning a comparative statistic used in cluster analysis. ASA Proceedings of the Social Statistics Section, 309–313.]. Based on those results, a method to predict the number of clusters is suggested by applying various agglomerative clustering algorithms. In the procedure, the methods using different indexes are examined and compared based on the concept of agreement (or, disagreement) between clusterings generated by different clustering algorithms on the set of data. Our method having practical generality works better than the other methods and assigns statistical meaning to Ck values in determining the number of clusters from the comparison. 相似文献
48.
Abstract This study applies a state-of-art optimization technique, SSDP/ESP (Sampling Stochastic Dynamic Programming with Ensemble Streamflow Prediction), to derive a monthly joint operating policy for the Nakdong multi-reservoir system in Korea. A rainfall-runoff model, SSARR (Streamflow Synthesis And Reservoir Regulation), is linked to the SSDP/ESP model to provide ESP scenarios for runoff during the next month in the Nakdong River basin. The primary advantage of the SSDP/ESP is that it updates the derived operating policy as new ESP forecasts become available. Another SSDP model that employs historical runoff scenarios (SSDP/Hist) is also developed. The main difference between the two SSDP models is that SSDP/Hist is an off-line model whereas the SSDP/ESP is on-line. The developed operating policies are tested with a simulation model using an object-oriented simulation software, STELLA. The simulation results show that SSDP/ESP is superior to SSDP/Hist with respect to the water supply criterion, although both models perform similarly with respect to the hydroelectric energy production criterion. 相似文献
49.
50.
Hyperspectral band selection aims at the determination of an optimal subset of spectral bands for dimensionality reduction
without loss of discriminability. Many conventional band selection approaches depend on the concept of “statistical distance”
measure between the probability distributions characterizing sample classes. However, the maximization of separability does
not necessarily guarantee that a classification process results in the best classification accuracies. This paper presents
a multidimensional local spatial autocorrelation (MLSA) measure that quantifies the spatial autocorrelation of the hyperspectral
image data. Based on the proposed spatial measure, a collaborative band selection strategy is developed that combines both
spectral separability measure and spatial homogeneity measure for hyperspectral band selection without losing the spectral
details useful in classification processes. The selected band subset by the proposed method shows both larger separability
between classes and stronger spatial similarity within class. Case studies in biomedical and remote sensing applications demonstrate
that the MLSA-based band selection approach improves object classification accuracies in hyperspectral imaging compared with
conventional approaches. 相似文献