• Journal of Information Processing Systems
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• 제15권6호
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• pp.1392-1405
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• 2019

The cathode voltage of aluminum electrolytic cell is relatively stable under normal conditions and fluctuates greatly when it has an anomaly. In order to detect the abnormal range of cathode voltage, an anomaly detection algorithm based on sliding window was proposed. The algorithm combines the time series segmentation linear representation method and the k-nearest neighbor local anomaly detection algorithm, which is more efficient than the direct detection of the original sequence. The algorithm first segments the cathode voltage time series, then calculates the length, the slope, and the mean of each line segment pattern, and maps them into a set of spatial objects. And then the local anomaly detection algorithm is used to detect abnormal patterns according to the local anomaly factor and the pattern length. The experimental results showed that the algorithm can effectively detect the abnormal range of cathode voltage.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.781-785
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• 2005

Cutting forces and tool deflection in end milling are represented as the closed form of tool rotational angle and cutting conditions. The discrete cutting forces caused by tool entry and exit are continued using the Fourier series expansion. Tool deflection is predicted by direct integration of the distributed loads on cutting edges. Cutting conditions, tool geometry, run-outs and the stiffness of tool clamping pan are considered for cutting forces and tool deflection estimation. Compared to numerical methods, the presented method has advantages in short prediction time and the effects of feeding and run-outs on cutting forces and tool deflection can be analyzed quantitatively. This research can be effectively used in real time machining error estimation and cutting condition selection for error minimization since the ferm accuracy is easily predicted by tool deflect ion curve.

• 로봇학회논문지
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• 제17권4호
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• pp.500-507
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• 2022

In this study, a motion planning method based on the integer representation of contact status between wheels and the ground is proposed for planning swing motion of a 6×6 wheel-legged robot to cross large obstacles and gaps. Wheel-legged robots can drive on a flat road by wheels and overcome large obstacles by legs. Autonomously crossing large obstacles requires the robot to perform complex motion planning of multi-contacts and wheel-rolling at the same time. The lift-off and touch-down status of wheels and the trajectories of legs should be carefully planned to avoid collision between the robot body and the obstacle. To address this issue, we propose a planning method for swing motion of robot legs. It combines an integer representation of discrete contact status and a trajectory optimization based on the direct collocation method, which results in a mixed-integer nonlinear programming (MINLP) problem. The planned motion is used to control the joint angles of the articulated legs. The proposed method is verified by the MuJoCo simulation and shows that over 95% and 83% success rate when the height of vertical obstacles and the length of gaps are equal to or less than 1.68 times of the wheel radius and 1.44 times of the wheel diameter, respectively.

• 한국생활과학회지
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• 제13권4호
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• pp.537-553
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• 2004

This ethnographic case-study explores the daily experiences in child-rearing and education among Korean full-time housewives. For this purpose, 11 full-time housewives in their thirties and forties from the middle class were interviewed with an unstructured questionnaire. The findings are as follows: Full-time housewives tend to assume the full responsibility for child-caring and education. Their time is structured around the schedules of caring children and participating in educational programs for children. The most demanding tasks for them include preparing for a preschool, getting the children ready for school, rendering supports for children's schools, extra curricular education, and arranging and offering gift money to teachers. They feel that their husbands do not provide enough supports for child-caring and education. Despite all the negative experiences, Korean full-time housewives put in whatever they have to make sure their children's well-being and to provide the best education possible for their children; the maternal identity plays a role of the utmost importance in them.

• 대한토목학회논문집
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• 제10권1호
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• pp.99-108
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• 1990

지형화적 순간단위도 이론을 이용하여 강우-유출 수문곡선을 재현할 수 있는 합성단위도법을 연구하였다. 지형학적 순간단위도는 Gupta등이 제한한 이론을 이용하였고, 응답함수는 2변수 감마분포를 사용하였다. 응답함수의 매개변수결정은 Rosso가 유도한 Horton의 지형법칙에 대한 회귀방정식과 유역지체시간의 저유계수에 대한 상관식을 이용하였다. 유도된 합성단위도의 적용성을 검토하기 위해 한강수계의 평창강과 낙동강수계의 위천유역에 대한 실측치와 비교하였다. 그리고 모멘트법과 불안전 감마함수를 사용한 최소자승법을 이용하여 수문응답의 재현정도를 비교 검토함으로서 본 연구에서 확립된 방법의 적용 타당성을 입증하였다. 분석결과 유도된 합성단위도는 첨두유량, 도달시간 그리고 수분곡선의 실측치에 대한 재현성이 비교적 높았으며, 미계측 유역의 유출해석에 중요한 수단을 제공할 것으로 판단되었다.

• Geomechanics and Engineering
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• 제2권4호
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• pp.229-252
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• 2010

In this paper, Soil-Structure Interaction (SSI) effect is investigated using a new and integrated approach. Faster solution of time dependant differential equation of motion is achieved using numerical representation of wavelet theory while dynamic Infinite Elements (IFE) concept is utilized to effectively model the unbounded soil domain. Combination of the wavelet theory with IFE concept lead to a robust, efficient and integrated technique for the solution of complex problems. A direct method for soil-structure interaction analysis in a two dimensional medium is also presented in time domain using the frequency dependent transformation matrix. This matrix which represents the far field region is constructed by assembling stiffness matrices of the frequency dependant infinite elements. It maps the problem into the time domain where the equations of motion are to be solved. Accuracy of results obtained in this study is compared to those obtained by other SSI analysis techniques. It is shown that the solution procedure discussed in this paper is reliable, efficient and less time consuming as compared to other existing concepts and procedures.

• 디자인학연구
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• 제9권
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• pp.701-712
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• 1994

We are in the process of the deepening of the informationalized society. Such a phenomenon(of deepening of the informationalized society) means that human being is surrounded by a linguistic or semiological environment instead of realistic experience. And it is concerned with the visual design composed by the visual languages and semiotics of Arts. Because the visual design is a kind of the linguisticsmion using the visual formation. This penomena necessarily brings the expansion of the quatity of information and accompanies the simplification of messages. Therefore when we apply the simplicity resulting from the ideality of KYEORE painting(the folk Art of Korea), it can be cotribute to those who should be in the center of semiological environment more deeply as a source to maximize the effect of communication, which is the conclusion of this study. In sort, the characteristics of our KYEORE painting is the ideal expression. There are found not a few problems such as the depiction of forms, the perspective representation, the chiaroscuro, the expression of material if we evaluate them from the western formative viewpoint. But the depiction of the fact is less direct than the ideal expression itself, is likely to be much complicated, and can be far away from the world of reality. Because it is just the first step for satisfying the ideal images in man. In the composition of KYEORE painting is dominated by the rules nonprescription of time amd place, colloquialism of the meaning, distinction maximization. They are all the compositive characteristics resulting from the ideality. If these characteristics are modulated intelligently to the current thoughts, they will help to build the new visual communication system of Korea which has more direct and fast absorption force.

• 대한조선학회논문집
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• 제28권1호
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• pp.1-11
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• 1991

선체 외판은 다양한 곡률을 가진 곡면으로 이루어져 있으므로 선박설계, 선각생산을 위한 선형의 기하하적 모델링에 있어서 순정작업은 시간이 많이 소요되는 일이나 피할 수 없는 작업이다. 본 논문에서는 교차순정법의 지루한 작업을 극복할 수 있는 수학적 순정법인 직접순정법을 제시하였다. 선체외판의 곡면표현을 위하여 3차의 B-spline 곡면식이 사용되었다. 순정작업은 외판의 변형에너지를 최소화하는 방법으로 수행되었다. 선체외판의 순정도 판정을 위하여 Gaussian 곡률과 판의 변형에너지의 값을 색상을 통하여 가시화 하였다. 순정작업에 의한 곡면모델로부터 산출된 선형의 기하학적 정보는 기본설계계산, 선각생산 등 선형과 관련된 전산시스템에 활용될 수 있도록 정보연계에 이용되었다.

• 패션비즈니스
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• 제6권2호
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• pp.29-40
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• 2002

Honor guards‘ dress represented by royal carriage parade. This thesis studies the ceremonial dress worn by the ceremonial troops during the Hwa-sung Hang-hang Ban-cha drawing (華城幸行班次圖) in the Chosun dynasty of King Jung-jo. The purpose of this study is to understand the national level ceremony by closely looking into the traditional ceremonial dress and the various signs that were used at these events thereby enhancing the cultural status of the Jung-jo King period. The Hwa-sung Hang-hang Ban-cha drawing(華城幸行班次圖) has its characteristics and also has commonality between the garments worn at these ceremonies. These garments are a traditional heritage brought down from many ages before and is a reflection of the changes that have occurred within our everyday life. Among these many records the Bancha-do(班次圖) is a representation of records that show what was worn by both nobles down to the ceremonial troops. The uniforms of the ceremonial troops were not only huge in size but also very diverse according to rank and grade. They used strong true colors with colorful flags, ceremonial items and musical instruments. These all added to the grandeur of the ceremony. The ceremonial flag was itself a symbol and was the core of the whole ceremony and parade. These ceremonial flags represented the heaven, sun, moon, hill and animals as well as supernatural gods. All these showed change in shape, color and content by age and time. Also the Yongmun Gichi(Dragon flag: 龍紋旗幟) is a supernatural being representing the power and wish of the ruler. The Chunsang-mun represents the indivisible relationship between man and heaven and also a metaphor for absolute power. A close look at ceremonial instruments show a direct representation towards power such as an axe, spear and sword and integrated with other large ceremonial items not only provided a shade but was also a representation of worship. These all were a more or less representation of authority. The musical instruments expressed the absolute authority of the ruler and maintained the marching order and also added grandeur to the parade. A summary of the ceremonial troops in the As seen above, these national ceremonies were a representation of the present power of authority and the will to rule. These ideas and the philosophy of “ruled by heaven” is represented here in the uniforms and the ceremony itself. The Bicentennial anniversary of the Nung - hang of February 1795 will be an excellent opportunity to show and inherit the tradition and recreation of our heritage. In this view we must look at the color and shape of traditional dress to be able to inherit and learn from our ancestors.

• 한국실내디자인학회논문집
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• 제27호
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• pp.145-151
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• 2001

There is so much difference in the way we perceive nature whether from eastern or western, present or past standpoint. however, awareness of coexistence between human beings and nature along with the concept that the most natural is th e most beautiful remain unchanged. The desire to describe the beauty of nature have existed all through the ages, but the (new) naturalism movement was spawned in our time when so much devastation and side effects took place for the expediency of nature, and field of display has been trying new interpretation of nature with direct or applied method. Naturalism trend is studied using the categories such as relationship between human and nature, space concept in western and eastern society, and the definition of view of nature in modern time. Elements of naturalism display are classified into the element of physical properties and element beyond the physical properties, and then methodology on naturalism display is investigated, using the illustration of display examples, in order to know the most essential elements of display, which are the physical properties such as space, light, object, glass, are expressed based on the elemental concept like nature, an accident, dynamic state, variability. As mentioned above, Naturalism display consists of physical properties and phenomenon. How to ive strong impression to a spectator depends on the ability to create effective space applying these elements. The significance of this study comes to surface in a time when the tremendous emphasis is put on the importance of nature and concerns about the role of display has become even greater.