• Journal of the Korean Society of Industry Convergence
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• v.10 no.2
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• pp.105-113
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• 2007

Accurate and low-cost sensor localization is a critical requirement for the deployment of wireless sensor networks in a wide variety of application. Sensor position is used for its data to be meaningful and for energy efficient data routing algorithm especially geographic routing. The previous works for sensor localization utilize global positioning system(GPS) or estimate unknown-location nodes position with help of some small reference nodes which know their position previously. However, the traditional localization techniques are not well suited in the senor network for the cost of sensors is too high. In this paper, we propose the sensor localization method with a mobile robot, which knows its position, moves through the sensing field along pre-scheduled path and gives position information to the unknown-location nodes through wireless channel to estimate their position. We suggest using the sensor position estimation method and an efficient mobility path model. To validate our method, we carried out a computer simulation, and observed that our technique achieved sensor localization more accurately and efficiently than the conventional one.

• The Journal of Korea Robotics Society
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• v.11 no.3
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• pp.127-132
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• 2016

For a practical mobile robot team such as carrying out a search and rescue mission in a disaster area, the localization have to be guaranteed even in an environment where the network infrastructure is destroyed or a global positioning system (GPS) is unavailable. The proposed architecture supports localizing robots seamlessly by finding their relative locations while moving from a global outdoor environment to a local indoor position. The proposed schemes use a cooperative positioning system (CPS) based on the two-way ranging (TWR) technique. In the proposed TWR-based CPS, each non-localized mobile robot act as tag, and finds its position using bilateral range measurements of all localized mobile robots. The localized mobile robots act as anchors, and support the localization of mobile robots in the GPS-shadow region such as an indoor environment. As a tag localizes its position with anchors, the position error of the anchor propagates to the tag, and the position error of the tag accumulates the position errors of the anchor. To minimize the effect of error propagation, this paper suggests the new scheme of full-mesh based CPS for improving the position accuracy. The proposed schemes assuring localization were validated through experiment results.

• Korean Journal of Social Welfare
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• v.56 no.3
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• pp.227-251
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• 2004

The objective of this study is to explore the characteristic of welfare for the disabled on the focus of 'Welfare Law for the Disabled' through multiple paradigm of disability. A proper understanding of disability theory requires more than a distinction between individual and social model approaches. It is also helpful to distinguish between materialist and idealist explanations. These two dimensions are used to generate a four-fold typology. In 'Welfare Law for the Disabled of 1981', individual materialist position was dominated. In 'Welfare Law for the Disabled of 1989', individual idealist position dawned to appear. In 'Welfare Law for the Disabled of 1999' which expanded diverse community services, individual idealist position was strengthened and social creationist position started to appear. Several characteristics are found out after analysis of 'Welfare Law for the Disabled of 1999'. Individual materialist position, individual idealist position, and social creationist position are mixed. Though the goal of the law is based on social creationist position, the central policies and measures are based on individual materialist position and individual idealist position. So it is necessary to amend 'Welfare Law for the Disabled' in the direction of including social creationist position and social constructionist position.

• Journal of the Korean Society of Physical Medicine
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• v.15 no.2
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• pp.121-128
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• 2020

PURPOSE: This study examined the changes in the cross-sectional area (CSA) of the abductor hallucis muscle during various ankle positions while performing toespread-out (TSO) exercise. METHODS: Thirty subjects with an average age of 22.1 years were recruited for this study. All subjects were firstly measured for the angle of their first metatarsophalangeal joint using a goniometer. Those with angles greater than 15° were allocated to the HV group. The remaining subjects were placed in the normal group. The CSA of the abductor hallucis was measured by ultrasound in the resting position with no movement and three ankle positions: neutral (0°), plantarflexion (30°), and dorsiflexion (30°). All data were analyzed using a two-way mixed analysis of variance between the groups (normal and HV group) and within the groups (resting, neutral, plantarflexion, and dorsiflexion) to determine the group x position interaction effects. RESULTS: During TSO exercise in the normal group, the CSA of the abductor hallucis was significantly greater in both the plantarflexion and neutral positions compared to the resting position (p_adj < .01), and plantarflexion was significantly greater than the dorsiflexion position (p_adj < .01). During the TSO exercise in the HV group, the CSA of the abductor hallucis for plantarflexion was significantly greater than it was for the resting, neutral, and dorsiflexion positions (p_adj < .01). CONCLUSION: Based on the above results, the TSO exercise in plantarflexion is an effective rehabilitation exercise for subjects with HV.

• Journal of Fisheries and Marine Sciences Education
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• v.25 no.3
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• pp.690-696
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• 2013

This study, which is conducted on two groups of skilled people and unskilled people, is purposed to analyze joint angle of lower extremity during short track speed skating in order to find out efficient body position and propose ideal training method. Short Track Speed Skating has a wide range of research areas, but their findings indicate a promising area for further research. Targeting 8 people who are skilled in short track speed skating and 8 people who are not skilled in it, this study analyzes three dimensional images using super-high speed camera to compare differences between these two groups of people. In this study, 6 sections of body positions including right foot push-off, right foot recovery, right foot basic position, left foot push-off, left foot recovery, and left foot basic position were analyzed using 8 super-high speed cameras of VICON. These body positions were analyzed in order to find out joint angles of the hip joint, the knee joint, and the ankle joint. In the section 4 of the inner and outer parts of the left hip angles showed significant difference, and most of the sections of knee joint angles also showed significant difference. In the section 1 and 2 of the plantar flexion, dorsiflexion of ankle joints showed significant difference(p<.001) It was found out that there were differences between groups of skilled people and unskilled people in terms of lower extremity's joint angles such as angles of the hip joint, the knee joint, and the ankle joint.

• Clinical and Experimental Pediatrics
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• v.49 no.6
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• pp.602-609
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• 2006

Purpose : As the prone position is thought to be an important factor in sudden infant death syndrome(SIDS), this study was conducted to contribute to reducing SIDS by analyzing sleeping positions of infants. Methods : A face-to-face questionnaire was carried out with a total of 170 parents with a baby aged less than 6 months. Results : A total of 170 infants included 95 males(55.9 percent) and 75 females(44.1 percent); their average age was 2.8 months. 45.3 percent slept in a supine position; 34.7 percent in a side or supine position; 7.1 percent in a side position; 4.7 percent in a prone position; 4.1 percent in a non-specific position. Among those in a side position, 59.7 percent were in a supine position in the morning; 19.5 percent were in the side position; 13.4 percent were in a non-specific position; and 4.1 percent were in a prone position. To the question why they slept in a specific position, 34.9 percent answered their baby slept comfortably, and particularly, 42.9 percent in the prone position group answered so. In the supine position group, 21.6 percent answered they had no reason. Both in the prone position and side position groups, 21 percent each answered they were worried about the shape of their baby's head. In the side position group, 22 percent answered that they had a fear of choking due to vomiting. In all sleeping position groups, 8.2 percent and 7.4 percent answered it was because they had a fear of suffocation and they wanted to avoid SIDS, respectively. Conclusion : Many of the parents preferred unstable positions, e.g. the side position and the prone position, which could cause SIDS. Their decision on their baby's sleeping position was not based on exact medical knowledge, but on convenience in taking care of their baby. As it was found that only 6 percent of the subjects were advised from their pediatrist about their baby's sleeping position, moreover, it is necessary to carry out more studies and activities for preventing SIDS caused by improper sleeping positions and educating patents about recommended sleeping positions for their baby.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.04a
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• pp.453-458
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• 2003

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.505-508
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• 2000

In order to determine the position and the content of fatty acids attached to glycerides and the migration degree of fatty acids in the migration reaction, hydrolysis of fish oil was carried out with lipolase-100T derived from Aspergillus oryzae. The content of fatty acids in the glyceride mixture was analyzed and compared with that of fish oil. The amounts of fatty acid in 2-position and the migration degree of the fatty acid in 2,3-DG (diglyceride) and 2-MG (monoglyceride) were calculated. The results showed that approximately 95% (w/w) of DHA (docosahexaenoic acid) and 65% of EPA (eicosapentaenoic acid) was attached to the 2-position of glycerides in the fish oil. Approximately 87% (w/w) of DHA and 75% of EPA remained in 2,3-DG and 88% of DHA and 65% of EPA in 2-MG were not involved in the migration reaction.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.10a
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• pp.214-219
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• 2001

For navigation of a mobile robot, it is one of the essential tasks of find out its current position. Dead reckoning is the most frequently used method to estimate its position. However conventional dead reckoner is prone to give us false information on the robot position especially when the wheels are slipping. This paper proposes an improved dead reckoning scheme using neural networks. The network detects the instance of wheel slipping and estimates the linear velocity of the wheel ; thus it calculates current position and heading angel of a mobile robot. The structure and variables of the neural network are chosen based on the analysis of slip motion robot. The structure and variables of the neural network are chosen based on the analysis of slip motion characteristics. A series of experiments are performed to investigate the performance of the improved dead reckoning system.

• Korean Management Science Review
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• v.34 no.2
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• pp.103-113
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• 2017

The artillery is a key element of the ground forces operation during wartime, and the military engineers support the artillery position development operation to support the smooth operation of the artillery. In establishing the artillery position development operation plan, the commander requires more than his intuition to find the best option reflecting a number of elements of the battlefield situation which changes every minute. Moreover, the number of available equipment is smaller than the number of required position developments, and the effective equipment operation becomes essential element of this issue. This study quantified the capability of the available engineering equipment, organized a number of teams enabling equipment to put out the maximum capacity based on the quantified figures, and formed the model which allocates the team to the developing points to minimize the developing time. The goal programming method was applied to resolve the problem. The developed model was applied to compare the total mission duration following the number of teams, the variable for commander's decision, and the result of this study can be used as the quantitative data for commander's decision making process in establishing the artillery position development support operation through effective equipment management.