• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.1
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• pp.9-21
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• 1998

This paper a new solution approach to moving obstacle avoidance problem of a mobile robot. A new concept avoidability measure (AVM) is defined to describe the state of a pair of a robot and an obstacle regarding the collision between them. As an AVM, virtual distance function (VDF), is derived as a function of the distance from the obstacle to the robot and outward speed of the obstacle relative to the robot. By keeping the virtual distance above some positive limit value, the robot avoids the obstacle. In terms of the VDF ,an artificial potential field is constructed to repel the robot away from the obstacle and to attract the robot toward a goal location. At every sampling time, the artificial potential field is updated and the force driving the robot is derived from the gradient of the artificial potential field. The suggested algorithm drives the robot to avoid moving obstacles in real time. Since the algorithm considers the mobility of the obstacle as well as the distance, it is effective for moving obstacle avoidance. Some simulation studies show the effectiveness of the proposed approach.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.11
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• pp.60-67
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• 1999

This paper proposes a robust oriented Hausdorff measure (ROHM) for 20D object matching. The ROHM is introduced by replacing the distance concept of the conventional Hausdorff distance (HD) algorithm by the accumulation scheme of the Hough transform (HT). The proposed algorithm can be considered as the modified directed HT using the distance transform (DT). The orientation information at each pixel is also used for removing incorrect correspondences. Experiments with various test images show that the performance of the proposed algorithm is better than that of conventional HD algorithms considered.

• Earthquakes and Structures
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• v.22 no.2
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• pp.147-155
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• 2022

Regarding the importance of seismic pounding, the available standards and guidelines specify minimum separation distance between adjacent buildings. However, the rules in this field are generally based on some simple assumptions, and the level of confidence is uncertain. This is attributed to the fact that the relative response of adjacent structures is strongly dependent on the frequency content of the applied records and the Eigen frequencies of the adjacent structures as well. Therefore, this research aims at investigating the separation distance of the buildings through a probabilistic-based algorithm. In order to empower the algorithm, the record-to-record uncertainties, are considered by probabilistic approaches; besides, a wide extent of material nonlinear behaviors can be introduced into the structural model by the implementation of the hysteresis Bouc-Wen model. The algorithm is then simplified by the application of the linearization concept and using the response acceleration spectrum. By implementing the proposed algorithm, the separation distance in a specific probability level can be evaluated without the essential need of performing time-consuming dynamic analyses. Accuracy of the proposed method is evaluated using nonlinear dynamic analyses of adjacent structures.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.333-338
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• 2007

The concept of "Allowable Load Set (ALS)" introduced by the author allows an easy understanding of load and strength characteristics of a structure in relation to its integrity under uncertainties. Two criteria of safety are introduced: A relative safety index denotes the distance to the boundary of the ALS and a normalized safety index is a distance in terms of functional value. They have been utilized in several examples, including multi-body mechanical systems such as a biomechanical system. Both formulations amount to robust designs in the sense that designs most insensitive to uncertainties are obtained in the context of newly defined safety indices, without using any input probability information.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1999.10a
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• pp.315-320
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• 1999

Obstacle Detection System(ODS) is a essential system for automated vehicle, such as AGV(Automatic Guided Vehicle), mobile robot. Automated vehicle must have a capability to detect and to avoid obstacles to guarantee a safe driving condition. To implement obstacle detection system, virtual bumper concept adapted. Like real bumper in a car, such as in the truck, it protects vehicle from collision using laser distance sensor. When an obstacle(such as other vehicle, building, etc) intrudes this virtual bumper area, a virtual force is calculated and produces necessary strategy to be able to avoid collision. In this paper, simplified virtual bumper concept is presented, and various problems when happens to implement are discussed.

• International Journal of Advanced Culture Technology
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• v.9 no.1
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• pp.105-113
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• 2021

Through the analysis of Gerhard Richter's works of art in the period of "fuzzy image", this paper expounds the special internal quality of fuzzy image in Richter's works and reveals an important direction of the development of contemporary easel painting, The special essence of Richter's vague image is that he uses photos to reflect the power and authenticity of the existence of the objective things. He was not satisfied with the radical way of modern painting and tried to return to the traditional way of painting, but in fact Richter kept a special distance between classical painting and modern art. Richter not only blurs the image in his creation, but also shows that he wants to show the objectivity of things, keep the distance, authenticity and give up painting. Richter used fuzzy images to capture the concept of "visual unconsciousness", and finally separated from the concept. When we read how Richter showed the reality of things in the way of painting, we also saw a kind of contradictory psychology when he faced the complicated objective.

• Journal of the Korea Safety Management & Science
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• v.25 no.1
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• pp.31-38
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• 2023

The object of this study is to evaluate whether the means of egress of Jechon Sports Center and Miryang Sejong Hospital, where massive fire human casualties occurred in 2017 and 2018 respectively, comply with NFPA 101(Life Safety Code), and to suggest the need for supplementation of domestic means of egress regulations. The study evaluated the number and arrangement of the means of egress, travel distance, common path of travel, dead end and discharge from exit for each building by applying the means of egress regulations of NFPA 101. As a result of the evaluation through NFPA 101, the travel distance was appropriate, but some of the other items except for the travel distance did not meet NFPA 101. The regulations that need to be supplemented are 1)occupant load calculation 2)egress capacity calculation 3)continuous concept of means of egress 4)concept of common path of travel. It is especially necessary to revise the requirement for fire door of the evacuation floor(normal 1^st floor) of the stairwell in case of below the five story building.

• Journal of applied mathematics & informatics
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• v.42 no.4
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• pp.749-759
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• 2024

In this manuscript, we formulate the notion of Ω(H, θ)-contraction on a self mapping f : W → W, this contraction based on the concept of Ω-distance mappings equipped on G-metric spaces together with the concept of H-simulation functions and the class of Θ-functions, we employ our new contraction to unify the existence and uniqueness of some new fixed point results. Moreover, we formulate a numerical example and a significant application to show the novelty of our results; our application is based on the significant idea that the solution of an equation in a certain condition is similar to the solution of a fixed point equation. We are utilizing this idea to prove that the equation, under certain conditions, not only has a solution as the Intermediate Value Theorem says but also that this solution is unique.

• Korean Journal of Human Ecology
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• v.14 no.5
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• pp.813-820
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• 2005

The beauty itself cannot be changed by the time, but the concept of the beauty can be influence by the time and cultural background. The purpose of this study is to analyze the beautiful faces or ugly faces among the young women and to provide useful guideline to make up for the modem concept of beauty. The facial photographs of 180 adlut women(aged between 20 and 29) in Pusan and Ulsan area were sampled to be measured and classified as the beautiful or ordinary or ugly faces. Data were analyzed by Frequencies, Mean, Duncan's Multiple Range Test. The major results were as followings; the Beautiful face has a relatively small face with a broad forehead and a small lower face. It also has a wide palpebral fissure, narrow intercanthal distance, a narrow nose and a big mouth. Physiognomic face length was 182.38mm, the upper face length was 59.82mm, the middle face length 60.82mm, the lower face length 61.76mm, and the index of face length to face breadth was 1.35. And also the faces within the figures are considered as the beautiful or ordinary or ugly faces from those measurements like face length/bizygion breadth, intercanthal distance, mouth width, upper vermilion height, lower vermilion height.

• Korean Parent-Child Health Journal
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• v.1
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• pp.115-126
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• 1998

It is the base of the health through life, the health of children is very important. The health education is the most effective measure for disease prevention and health promotion. To educate children for the health, we must consider their concept of the health before. Therefore I attempted this study for investigation for the concept about respiratory communicable disease which is one of the most important health problems. The design of this study was descriptive investigational study. The subjects of this study are 4-6 aged 65 children who are attending district nursery school. The tools of this study constituted 3 parts as an etiological agents, environmental agents and host agents. The data were collected by an individual interview and cartoon cards. The results of this study are as followed: 1. The preschool children tend to think contamination along the physical distance, nearer things more relational. 2. The preschool children tend to have their experience centered thinking. 3. There was a highly significant correlation between the children's age and knowledge scores(r = 0.431, P= 0.0003). 4. There wasn't a significant correaltion between sex group. In conclusion, it wad founded that the preschool have a tendancy to think communicable disease along the physical distance and their daily life experiences. This results support the Piaget's cognitive developmental theory. Therefore, to develop the health education program for preschool students, above results must be referenced.