• Journal of the Korean Society for Precision Engineering
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• v.27 no.1
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• pp.125-133
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• 2010

A versatile micro-robotic platform for micro/nano scale assembly has been demanded in a variety of application areas such as micro-biology and nanotechnology. In the near future, a flexible and compact platform could be effectively used in a scanning electron microscope chamber. We are developing a platform that consists of miniature mobile robots and a compact positioning stage with multi degree-of-freedom. This paper presents the design and the implementation of a low-cost and compact multi degree of freedom position sensor that is capable of measuring absolute translational and rotational displacement. The proposed sensor is implemented by using a CMOS type image sensor and a target with specific hole patterns. Experimental design based on statistics was applied to finding optimal design of the target. Efficient algorithms for image processing and absolute position decoding are discussed. Simple calibration to eliminate the influence of inaccuracy of the fabricated target on the measuring performance also presented. The developed sensor was characterized by using a laser interferometer. It can be concluded that the sensor system has submicron resolution and accuracy of ${\pm}4{\mu}m$ over full travel range. The proposed vision-based sensor is cost-effective and used as a compact feedback device for implementation of a micro robotic platform.

• Korean Journal of Cognitive Science
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• v.1 no.2
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• pp.221-239
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• 1989

The purpose of this study was to explore the processing unit in Korean word.Three experiments were conducted to examine this question.Preliminary experiment and Enperiment I were executed to delineate the processing unit in singles syllable word and Experiment 2,for words two or more syllables.The major finding of the preliminary experiment showed that the effect of the consonant type was not significant but that of the letter position was.Reaction time increased as the position of letter increased.The difference in reaction time between the first and the second position was not significant.However,the difference between the second and third was.In the Experiment 1, the effect of the number of letter was significant: reaction time increased as the number of letters increased.The size of the position effect both in the preliminary experiment and Experiment 1was comparable.Result of Experiment 2 was such that regardless of the presence of the final consonant(s),the reaction time incresased linearly as the number of svllables increased from two to four. The findings of the present study suggest that:(1)processing unit in single syllable Korean words is a syllable without the final consonant(s):(2) but in words of two or more syllables,the unit is likely to be a syllable with the final consonant(s).

• The Journal of the Korea Contents Association
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• v.15 no.4
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• pp.263-276
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• 2015

This study aimed to examine the relationship between lifestyle in early recollections and life position of adolescence. The data was collected from 409(male 201, female 208) middle school students. To analyze the data, factor analysis, Pearson correlation coefficient, MANOVA and multiple regression were used. The major results of this study were as follows: First, it was proved that the correlation coefficient of those variables between lifestyle and life position were statistically significant. In particular, to BSI & WR were positively associated with I+ & U+, while GA & BC were positively associated with I- & U-. Second, U- had greatest influence on GA, I+ & U+ had greatest influence on WR, I- had greatest influence on BC. Based on the finding results, discussion and implication for further research were suggested.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.16-24
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• 2017

The purpose of this paper is to search the optimal location of offset outrigger system in high-rise building after a structural schematic design of 80 stories building was conducted, making use of MIDAS-Gen. In this research, the key factors of analysis study were column stiffness, outrigger position in plan and outrigger location in height. For the aim of finding out the optimum position of offset outrigger system in tall building, we studied the lateral displacement in top floor which is the very essential variables in the structural design of high-rise building. The results of study showed that the column stiffness, the outrigger location in plan and outrigger location in height had an effect on the optimal position of outrigger system. Also, it is indicated that the research results can be useful in acquiring the structural design materials for seeking the optimum position of offset outrigger system in tall building.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.905-911
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• 2017

Effects of injector position and momentum flux ratio on a vertical jet in a cross flow field were studied qualitatively and shown by using air and water. The experiment was carried out by fixing the momentum flux ratio and varying the position of the injector hole. Conversely, the injector hole position was fixed and the momentum flux ratio was varied. Image visualization was performed by a Shadowgraph technique using a high speed camera. The visualized images were compared for finding differences in spraying through Density Gradient Magnitude Image. It is observed that as the x/d of the apparatus increased the jet break up height decreases and the spray angle also decreases. When x/d is 0, the spray reaches the floor and ceiling at any momentum flux ratio.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3513-3520
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• 2012

This study aimed to investigate the difference of the body orientation ability in sitting position to adapt to dynamically changing angle of the base of support in stroke patients and Healthy adults. The angle between vertical and head and trunk in 12 stroke patients (6 male and 6 female) and 12 healthy adults (6 male and 6 female) were measured by video motion analysis system. The head and trunk angle between stroke patients and healthy adults in sitting position were significantly different when increase the angle of dominant side(p<.05). The head and trunk angle between stroke patients and healthy adults in sitting position were significantly different when increase the angle of non-dominant side(p<.05). The head and trunk angle between stroke patients and healthy adults in sitting position were significantly different when decrease the angle of non-dominant side(p<.05). The head angle between stroke patients and healthy adults in sitting position was significantly different(p<.05), but the trunk angle was not significantly different when decrease the angle of dominant side(p>.05), Stroke patients compared to healthy adults had more deficits in their body orientation ability in sitting position to adapt to dynamically changing angle of the base of support. This finding may help to understand postural control deficits more clearly in stroke patients in sitting position.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.2
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• pp.151-157
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• 2013

The law for indicating the address based on the street name has taken effect in 1997. The address based on land-lot number will be changed to the address based on the street name giving odd numbers to the buildings situated on the left side and even numbers to the buildings situated on the right side per street. Searching locations by street name addresses is possible for residential areas, on the other hand, the system of finding locations is insufficient for farmlands, mountains and others, so it is unable to cope with crimes and emergency rescue. In order to make up for the weak points of street name address, the national point number, grid reference system was introduced for finding location of non-residential areas. Therefore, the purpose of this paper is to help the introduction the national point number. In this paper, we proposed a territory-oriented control point and grid range for the national point number. Numbering scheme of grid zone shall be alphanumeric, a two-letter pair Hangul and the grid coordinates in terms of Easting and Northing. We also proposed the notice area for the national point number and location of signs, application about the public and private sector.

• Herbal Formula Science
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• v.20 no.2
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• pp.55-63
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• 2012

Objectives : This study was conducted to investigate the safety of Bangpungtongsung-san in rats. Methods : The safety of this prescription on acute toxicity was evaluated by single dose toxicity study. Rats were orally administrated in a single dose of 0 and 2,000 mg/kg(limited dose) Bangpungtongsung-san. There were 7 rats in each groups. All animals were sacrificed after 14 days of treatment. After single administration, mortality, clinical signs, and body weight changes were observed for 14 days. Three parameters(autopsy finding, clinical chemistry, and hematology) were tested on the last day. Results : In this study with rats, Bangpungtongsung-san treatment did not show any acute toxicity. No mortality was noted for 14 days of treatment. There were no adverse effects on clinical signs, body weight changes, and autopsy finding at all treatment groups. The clinical chemistry parameters attesting to liver and kidney functions as well as the hematological parameters were within the normal ranges. Conclusions : It is considered that $LD_{50}$ of Bangpungtongsung-san is over 2,000 mg/kg in oral administration by rats. This finding of the safety of Bangpungtongsung-san is expected to strengthen the position of this prescription as nontoxic medicine.

• The Journal of Korea Robotics Society
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• v.5 no.2
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• pp.152-159
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• 2010

Finding a head of a person in a scene is very important for taking a well composed picture by a robot photographer because it depends on the position of the head. So in this paper, we propose a robust head tracking algorithm using a hybrid of an omega shape tracker and local binary pattern (LBP) AdaBoost face detector for the robot photographer to take a fine picture automatically. Face detection algorithms have good performance in terms of finding frontal faces, but it is not the same for rotated faces. In addition, when the face is occluded by a hat or hands, it has a hard time finding the face. In order to solve this problem, the omega shape tracker based on active shape model (ASM) is presented. The omega shape tracker is robust to occlusion and illuminationchange. However, whenthe environment is dynamic,such as when people move fast and when there is a complex background, its performance is unsatisfactory. Therefore, a method combining the face detection algorithm and the omega shape tracker by probabilistic method using histograms of oriented gradient (HOG) descriptor is proposed in this paper, in order to robustly find human head. A robot photographer was also implemented to abide by the 'rule of thirds' and to take photos when people smile.

• Journal of Korean Academy of Nursing
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• v.33 no.2
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• pp.200-209
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• 2003

Purpose: This study was to identify the prevalence of orthostatic hypotension and its association with risk factors of orthostatic hypotension aged over 60 in Seoul and Chungju, Korea. Method: The data were collected from the 22th of August, 2000 to the 7th May 2001. The participants were 74 community-dwelling aged who could stand up from sitting position without assistance. Subjects were interviewed with structured questionnaire in order to ask experience of previous falls, hours in per day, symptoms related orthostatic hypotension and demographic characteristics. Orthostatic hypotension was assessed at 1 minute after the subjects standing from sitting position and defined as 20mmHg or greater decrease in systolic blood pressure after standing. Result: The prevalence of orthostatic hypotension was 17.1%. The mean drop of systolic blood pressure was 27.46mmHg among orthostatic hypotension subjects. The significant variables which explain the occurrence of orthostatic hypotension was the basal systolic blood pressure, the hit ratio of discriminant function with basal systolic blood pressure was 69.7%. Conclusion: Finding indicate that this study will contribute to develop nursing strategies to identify risk factors and to prevent orthostatic hypotension for the aged.