• Journal of the Korean Geotechnical Society
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• v.17 no.4
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• pp.191-198
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• 2001

국내 도로포장의 주요 파손형태는 주변환경 및 반복 교통하중 조건에 의한 소성변형(rutting), 피로균열, 반사균열, 온도균열 등이 있는데, 포장이 설계수명에 도달하기 이전에 주로 발생하며 이로 인한 도로포장의 유지관리에 막대한 국가예산이 낭비되고 있는 실정이다. 본 연구에서는 토목섬유 아스팔트 포장 시스템을 체계적으로 정립하기 위해 휠트래킹 시험과 균열저항성 시험을 수행하여 토목섬유 아스팔트 포장의 소성변형 및 균열 저항성을 분석하였다. 이러한 실험결과를 통해 아스팔트 포장에서의 토목섬유 보강 효과가 평가되었다.

• Proceedings of the Korean Information Science Society Conference
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• 2004.04b
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• pp.193-195
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• 2004

유비쿼터스 환경에서 모든 이동 객체들의 정확한 위치를 추적하는 것은 현실상 불가능하므로, 현실적인 대안으로 위치 추적 방법을 사용 찬다. 현재 위치 추적 방법들은 많이 개발되고 있지만 이것을 비교 실험할 수 있는 환경이 미흡한 실정이다. 이에, 본 논문에서는 여러 가지 위치 추적 방법을 비교 실험 할 수 있는 테스트 베드 시스템을 구현하였다. 또한 본 논문에서 구현한 테스트 베드 시스템에서 현재 나와 있는 여러 가지 위치 추적 방법을 실험을 통해 비교, 분석해 보았다.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.4
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• pp.159-166
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• 2016

In this paper, an active object tracking system basing on the pan/tilt-embedded stereo camera system is suggested and implemented. In the proposed system, once the face area of a target is detected from the input stereo image by using a YCbCr color model and phase-type correlation scheme and then, using this data as well as the geometric information of the tracking system, the distance and 3D information of the target are effectively extracted in real-time. Basing on these extracted data the pan/tilted-embedded stereo camera system is adaptively controlled and as a result, the proposed system can track the target adaptively under the various circumstance of the target. From some experiments using 480 frames of the test input stereo image, it is analyzed that a standard variation between the measured and computed the estimated target's height and an error ratio between the measured and computed 3D coordinate values of the target is also kept to be very low value of 1.03 and 1.18% on average, respectively. From these good experimental results a possibility of implementing a new real-time intelligent stereo target tracking and surveillance system using the proposed scheme is finally suggested.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.869-875
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• 2009

Safety is a big issue in the construction sites. For safe and secure management, tracking locations of construction resources such as labors, materials, machineries, vehicles and so on is important. The materials, machineries and vehicles could be controlled by computer, whereas the movement of labors does not have fixed pattern. So, the location and movement of labors need to be monitored continuously for safety. In general, Global Positioning System(GPS) is an opt solution to obtain the location information in outside environments. But it cannot be used for indoor locations as it requires a clear Line-Of-Sight(LOS) to satellites Therefore, indoor location monitoring system could be a convenient alternative for environments such as tunnel and indoor building construction sites. This paper presents a case study to investigate feasibility of Wi-Fi based indoor location monitoring system in construction site. The system is developed by using fingerprint map of gathering Received Signal Strength Indication(RSSI) from each Access Point(AP). The signal information is gathered by Radio Frequency Identification (RFID) tags, which are attached on a helmet of labors to track their locations, and is sent to server computer. Experiments were conducted in a shield tunnel construction site at Guangzhou, China. This study consists of three phases as follows: First, we have a tracking test in entrance area of tunnel construction site. This experiment was performed to find the effective geometry of APs installation. The geometry of APs installation was changed for finding effective locations, and the experiment was performed using one and more tags. Second, APs were separated into two groups, and they were connected with LAN cable in tunnel construction site. The purpose of this experiment was to check the validity of group separating strategy. One group was installed around the entrance and the other one was installed inside the tunnel. Finally, we installed the system inner area of tunnel, boring machine area, and checked the performance with varying conditions (the presence of obstacles such as train, worker, and so on). Accuracy of this study was calculated from the data, which was collected at some known points. Experimental results showed that WiFi-based indoor location system has a level of accuracy of a few meters in tunnel construction site. From the results, it is inferred that the location tracking system can track the approximate location of labors in the construction site. It is able to alert the labors when they are closer to dangerous zones like poisonous region or cave-in..

• The Journal of Korean Physical Therapy
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• v.26 no.3
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• pp.163-168
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• 2014

Purpose: The purpose of this study was to investigate whether ipsilateral shoulder pain affects the sensorimotor function of the same side shoulder in patients with stroke. Methods: Thirty stroke patients, who were divided into the ipsilateral shoulder pain group (n=15) and the ipsilateral shoulder non-pain group (n=15). Subjects were evaluated on performance of a tracking task, joint reposition test and 9-Hole pegboard test for sensorimotor functions, and Fugl-Meyer test and Motricity Index for functional ability of the contralateral side. Results: In comparison of the two groups, significant differences in performance on functional ability, including the Fugl-Meyer test(both upper and lower limb) and Motricity Index(only lower limb) were observed (p<0.05). With regard to sensorimotor functions, the ipsilateral shoulder pain group were observed significantly poor scores on the Accuracy Index, joint reposition score and 9-Hole pegboard test, when compared with the ipsilateral shoulder non-pain group (p<0.05). Conclusion: We found that ipsilateral shoulder pain could impede accurate performance of a movement and result in deteriorated proprioception of the ipsilateral shoulder. Therefore, careful evaluation and appropriate therapeutic intervention are essential for stroke patients who suffer from ipsilateral shoulder pain.

• Physical Therapy Korea
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• v.12 no.4
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• pp.7-11
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• 2005

The purposes of this study were to investigate the effects of variability of training on the acquisition of motor skill of closed loop type tracking task using Rotary Pursuit, and to determine if there was a bilateral transfer effect to the non-dominant hand following practice with the dominant hand. Twelve healthy volunteer students (5 males and 7 females, aged 25 to 37) were randomly divided into a constant practice group and a variable practice group. A photoelectric rotary pursuit apparatus with stop clock and repeat cycle timer by Lafayette Instrumentation Co. was used for this study. Rotary pursuit is a closed loop task in which a subject attempts to keep a photoelectric stylus on a lighted target in motion. Subjects performed the clockwise circular pursuit task while standing. Experimental procedure was divided into three sessions, namely, pre-test, training, and post-test. The constant group practiced all 60 trials at 30 rpm. Variable practice group did a varied practice session with 15 trials at speeds of 20 rpm, 26 rpm, 34 rpm, and 46 rpm. No one in either group practiced with their non-dominant arm. A Mann-Whitney test and a Wilcoxon Signed Ranks test were used for statistical analyses. The results of this study showed no different training effect between groups on the post-test with the dominant hand. However, bilateral transfer effect of rotary pursuit task between hands was demonstrated. Possible mechanisms are discussed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.481-484
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• 2003

Recently polymer insulators are being used for outdoor high voltage applications. Polymer insulators have significant advantages over porcelain and glass insulators. With the gradual improvement of their design and material, their reliability has also increased. It is however difficult to establish how they will perform after several years of service. Aging of the insulator weathershed may lead to damages such as excessive chalking and crazing, erosion and tracking which affect the insulator performance. In service insulator are subjected to aging stresses such as humidity, pollution and electrical field which act singly or in combination. There have been numerous accelerated laboratory tests developed with the intention of evaluating suitability of polymeric materials. Some of these are strictly material tests, where as, others evaluate full scale devices. Service experience plays a key role in the utility selection of polymer insulator, but is time consuming, and may not always be available. Hence there is a need for a meaningful and reliable accelerated aging test for polymer insulator. This paper describes multi-stress aging test for reliability of polymer insulator This paper presents the rule of multi-stress aging test and test chamber for polymer insulator in korea electrotechnology research institute.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.9
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• pp.878-886
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• 2012

This paper investigates the implementation and flight test of realtime vision guided autopilot system based on virtual instrumentation platform. A graphical design process via virtual instrumentation platform is fully used for the image processing, communication between systems, vehicle dynamics control, and vision coupled guidance algorithms. A significatnt ojective of the algorithm is to achieve an environment robust autopilot despite wind and an irregular image acquisition condition. For a robust vision guided path tracking and hovering performance, the flight path guidance logic is combined in a multi conditional basis with the position estimation algorithm coupled with the vehicle attitude dynamics. An onboard flight test equipped with the developed realtime vision guided autopilot system is done using the rotary UAV system with full attitude control capability. Outdoor flight test demonstrated that the designed vision guided autopilot system succeeded in UAV's hovering on top of ground target within about several meters under geenral windy environment.

• Journal of the Korean Society of Industry Convergence
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• v.22 no.2
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• pp.155-161
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• 2019

Recently, increases in major disasters such as fires, earthquakes and typhoons have raised public expectations for safety. In addition to this increase in expectations of safety, the government continues to push for more manpower and better treatment for firefighters who are operating in the disaster scene. Despite the improvement of working conditions and increased welfare for firefighters, however, the incidence and turnover of various mental diseases continues to increase. It is reported that many of the diseases such as post-traumatic stress disorder and the turnover of firefighters are due to a mismatch in individual's personality and work environment. In this study, 108 firefighters were evaluated for their vocational aptitude in the new curriculum. Based on the analysis results, new firefighters were proposed to provide employment and education training improvements, and to provide job security suitable for the individual's personality type through the introduction of the vocational aptitude test for firefighters who are working in the fire service. In addition, we would like to use the vocational aptitude test as a material for reducing post-traumatic stress disorder and increasing turnover through long-term tracking and observation, rather than from a one-off perspective.

• Journal of Advanced Navigation Technology
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• v.16 no.6
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• pp.910-919
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• 2012

In this paper, we described development of on-board image processing system and its process and verified its performance through flight experiment. The image processing board has single ARM(Advanced Risk Machine) processor. We performed Embedded Linux Porting. Algorithm to be applied for object tracking is color-based image processing algorithm, it can be designed to track the object that has specific color on ground in real-time. To verify performance of the on-board image processing system, we performed flight test using the PNUAV, UAV developed by LAB. Also, we performed optimization of the image processing algorithm and kernel to improve real-time performance. Finally we confirmed that proposed system can track the blue-color object within four pixels error range consistently in the experiment.