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51.
Kyung Seob Lim Jun-Kyu Park Myung Ho Jeong Jae-Woon Nah Dae Sung Park Jong Min Kim Jung Ha Kim So Youn Lee Eun Jae Jang Suyoung Jang Hyun Kuk Kim Doo Sun Sim Keun-Ho Park Young Joon Hong Youngkeun Ahn Jung Chaee Kang 《Journal of materials science. Materials in medicine》2016,27(4):66
The aim of this study was to evaluate antiproliferative sirolimus- and antioxidative alpha-lipoic acid (ALA)-eluting stents using biodegradable polymer [poly-l-lactic acid (PLA)] in a porcine coronary overstretch restenosis model. Forty coronary arteries of 20 pigs were randomized into four groups in which the coronary arteries had a bare metal stent (BMS, n = 10), ALA-eluting stent with PLA (AES, n = 10), sirolimus-eluting stent with PLA (SES, n = 10), or sirolimus- and ALA-eluting stent with PLA (SAS, n = 10). A histopathological analysis was performed 28 days after the stenting. The ALA and sirolimus released slowly over 30 days. There were no significant differences between groups in the injury or inflammation score; however, there were significant differences in the percent area of stenosis (56.2 ± 11.78 % in BMS vs. 51.5 ± 12.20 % in AES vs. 34.7 ± 7.23 % in SES vs. 28.7 ± 7.30 % in SAS, P < 0.0001) and fibrin score [1.0 (range 1.0–1.0) in BMS vs. 1.0 (range 1.0–1.0) in AES vs. 2.0 (range 2.0–2.0) in SES vs. 2.0 (range 2.0–2.0) in SAS, P < 0.0001] between the four groups. The percent area of stenosis based on micro-computed tomography corresponded with the restenosis rates based on histopathological stenosis in different proportions in the four groups (54.8 ± 7.88 % in BMS vs. 50.4 ± 14.87 % in AES vs. 34.5 ± 7.22 % in SES vs. 28.9 ± 7.22 % in SAS, P < 0.05). SAS showed a better neointimal inhibitory effect than BMS, AES, and SES at 1 month after stenting in a porcine coronary restenosis model. Therefore, SAS with PLA can be a useful drug combination for coronary stent coating to suppress neointimal hyperplasia. 相似文献
52.
53.
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
54.
A dual‐polarized X‐band conformal array antenna is presented for unmanned aerial vehicles with polarimetric radars/sensors. Starting from the planar structure, the array antenna consisted of sixteen 2 × 2 subarrays is conformal to the cylinders with various curvature radii to fit the payload box of the airborne vehicle. The return losses are almost constant even if the curvature radius changes. Measured radiation patterns are compared with various curvatures at the same frequencies. The array can be easily placed on the aircraft payload or fuselage due to its ultra thin thickness, ultra lightweight, and conformal structure, which has potential airborne applications in polarimetric radar surveillance, remote sensing, and wireless communications. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011. 相似文献
55.
Jonghee M. Youn Minwook Ahn Yunheung Paek Jongwung Kim Jeonghun Cho 《Journal of Systems Architecture》2010,56(8):368-383
The complexity of today’s embedded applications increases with various requirements such as execution time, code size or power consumption. To satisfy these requirements for performance, efficient instruction set design is one of the important issues because an instruction customized for specific applications can make better performance than multiple instructions in aspect of fast execution time, decrease of code size, and low power consumption. Limited encoding space, however, does not allow adding application specific and complex instructions freely to the instruction set architecture. To resolve this problem, conventional architectures increases free space for encoding by trimming excessive bits required beyond the fixed word length. This approach however shows severe weakness in terms of the complexity of compiler, code size and execution time. In this paper, we propose a new instruction encoding scheme based on the dynamic implied addressing mode (DIAM) to resolve limited encoding space and side-effect by trimming. We report our two versions of architectures to support our DIAM-based approach. In the first version, we use a special on-chip memory to store extra encoding information. In the second version, we replace the memory by a small on-chip buffer along with a special instruction. We also suggest a code generation algorithm to fully utilize DIAM. In our experiment, the architecture augmented with DIAM shows about 8% code size reduction and 18% speed up on average, as compared to the basic architecture without DIAM. 相似文献
56.
Gu-Min Jeong Hyun-Sik Ahn Sang-Il Choi Nojun Kwak Chanwoo Moon 《International Journal of Control, Automation and Systems》2010,8(1):141-148
In this paper, we propose a new pattern recognition method using feature feedback and present its application to face recognition.
Conventional pattern recognition methods extract the features employed for classification using PCA, LDA and so on. On the
other hand, in the proposed method, the extracted features are analyzed in the original space using feature feedback. Using
reverse mapping from the extracted features to the original space, we can identify the important part of the original data
that affects the classification. In this way, we can modify the data to obtain a higher classification rate, make it more
compact or abbreviate the required sensors. To verify the applicability of the proposed method, we apply it to face recognition
using the Yale Face Database. Each face image is divided into two parts, the important part and unimportant part, using feature
feedback, and the classification performed using the feature mask obtained from feature feedback. Also, we combine face recognition
with image compression. The experimental results show that the proposed method works well. 相似文献
57.
With the development in IT technology and with growing demands of users, a ubiquitous environment is being made. Because individual
identification is important in ubiquitous environment, RFID technology would be used frequently. RFID is a radio frequency
identification technology to replace bar code. The reader transmits query (request of user information) and tag-provides user
information. RFID has various advantages, such as high speed identification rates, mass memory storages. However, eavesdropping
is possible as well as a problem that user information is exposed (Juels et al. in Conference on Computer and Communications
Security—ACM CCS, pp. 103–111, 2003; Ohkubo et al. in RFID Privacy Workshop 2003; Weis et al. in International Conference on Security in Pervasive Computing, pp. 201–212, 2003; Weis et al. in Cryptographic Hardware and Embedded Systems—CHES, pp. 454–469, 2002). Therefore, when off-line customer had visited bank for banking service, RNTS (RFID number ticket service) system provides
both anonymity in customer identification and efficiency of banking service. In addition, RNTS system protects privacy of
an off-line user visiting the bank and it is an efficient method offering service in order of arriving in the bank. 相似文献
58.
Case-based reasoning (CBR) is one of the most popular prediction techniques in medical domains because it is easy to apply, has no possibility of overfitting, and provides a good explanation for the output. However, it has a critical limitation – its prediction performance is generally lower than other AI techniques like artificial neural networks (ANN). In order to obtain accurate results from CBR, effective retrieval and matching of useful prior cases for the problem is essential, but it is still a controversial issue to design a good matching and retrieval mechanism for CBR systems. In this study, we propose a novel approach to enhance the prediction performance of CBR. Our suggestion is the simultaneous optimization of feature weights, instance selection, and the number of neighbors that combine using genetic algorithms (GA). Our model improves the prediction performance in three ways – (1) measuring similarity between cases more accurately by considering relative importance of each feature, (2) eliminating useless or erroneous reference cases, and (3) combining several similar cases represent significant patterns. To validate the usefulness of our model, this study applied it to a real-world case for evaluating cytological features derived directly from a digital scan of breast fine needle aspirate (FNA) slides. Experimental results showed that the prediction accuracy of conventional CBR may be improved significantly by using our model. We also found that our proposed model outperformed all the other optimized models for CBR using GA. 相似文献
59.
Stephen G. McGill Seung‐Joon Yi Hak Yi Min Sung Ahn Sanghyun Cho Kevin Liu Daniel Sun Bhoram Lee Heejin Jeong Jinwook Huh Dennis Hong Daniel D. Lee 《野外机器人技术杂志》2017,34(4):775-801
This paper describes Team THOR's approach to human‐in‐the‐loop disaster response robotics for the 2015 DARPA Robotics Challenge (DRC) Finals. Under the duress of unpredictable networking and terrain, fluid operator interactions and dynamic disturbance rejection become major concerns for effective teleoperation. We present a humanoid robot designed to effectively traverse a disaster environment while allowing for a wide range of manipulation abilities. To complement the robot hardware, a hierarchical software foundation implements network strategies that provide real‐time feedback to an operator under restricted bandwidth using layered user interfaces. Our strategy for humanoid locomotion includes a backward‐facing knee configuration paired with specialized toe and heel lifting strategies that allow the robot to traverse difficult surfaces while rejecting external perturbations. With an upper body planner that encodes operator preferences, predictable motion plans are executed in unforeseen circumstances. These plans are critical for manipulation in unknown environments. Our approach was validated during the DRC Finals competition, where Team THOR scored three points in 18 min of operation time, and the results are presented along with an analysis of each task. 相似文献
60.
Chin-Gook Lhee Jae-Sam Park Hyun-Sik Ahn Do-Hyun Kim 《Fuzzy Systems, IEEE Transactions on》2001,9(2):343-348
In this paper, a fuzzy logic controller (FLC) is designed based on the similarity between the FLC and the sliding mode control (SMC). The proposed scheme provides the sliding mode-like FLC with fast self-tuning the dead-zone parameters (boundary layer thickness) under parameter variations of the controlled system. To show the validity and the effectiveness of the proposed control method, simulations are performed for the position control of a rotary inverted pendulum 相似文献