• Journal of the Korean Society for Precision Engineering
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• v.15 no.1
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• pp.78-86
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• 1998

This paper presents a numerical method of the minimum-time trajectory planning for a robot manipulator amid obstacles. Each joint displacement is represented by the linear combination of the finite-term quintic B-splines which are the known functions of the path parameter. The time is represented by the linear function of the same path parameter. Since the geometric path is not fixed and the time is linear to the path parameter, the coefficients of the splines and the time-scale factor span a finite-dimensional vector space, a point in which uniquely represents the manipulator motion. The displacement, the velocity and the acceleration conditions at the starting and the goal positions are transformed into the linear equality constraints on the coefficients of the splines, which reduce the dimension of the vector space. The optimization is performed in the reduced vector space using nonlinear programming. The total moving time is the main performance index which should be minimized. The constraints on the actuator forces and that of the obstacle-avoidance, together with sufficiently large weighting coefficients, are included in the augmented performance index. In the numerical implementation, the minimum-time motion is obtained for a planar 3-1ink manipulator amid several rectangular obstacles without simplifying any dynamic or geometric models.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.3 no.1
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• pp.209-221
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• 1999

Several approaches to anlayzing real-time schedulability have been presented, but since these used a fixed priority scheduling scheme and/or traverse all possible state spaces, there take place exponential time and space complexity of these methods. Therefore it is necessary to reduce the state space and detect schedulability at earlier time. This paper proposes and implements an advanced schedulability analysis algorithm to determine that is satisfied a given deadlines for real-time processes. These use a minimum execution time of process, periodic, deadline, and a synchronization time of processes to detect schedulability at earlier time and dynamic scheduling scheme to reduce state space using the transition rules of process algebra. From a result of implementation, we demonstrated the effective performance to determine schedulability analysis.

• Korean Institute of Interior Design Journal
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• v.20 no.5
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• pp.217-225
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• 2011

The meaning and role of public space has existed based on the periodical situation like history. The more the time has passed, the faster the meaning of it has changed. We can see the differences of it from the one which used to be. This study is about Platoon Kunsthalle which is so-called the complex cultural space. The purpose of this study is to show how the user is related to the program for the planning of the public space. It is based on the procedure of the research with absorbing the place. The people who are using the space are absorbed for knowing the user's action. And then, the specific actions are written and the status of the using space is photographed. The research is based on asking and answering about that. The result of this study is as follows : The first is that young people between 20's and 30's are using a hall comparing with other age through daily using of space and features of users. Also, Using between 7p.m. and 9p.m., a dinnertime, takes the first place and using of meals and beverages is major at lunch due to restaurant and bar. User behavior of "sitting" is the biggest part and the hall is used for the public purpose connected with "talking". The second is that the daily hall space is classified with the spacial area indirectly based on the condition. Also, it depends on the time and the using. The third is that the unusual hall space is depended on the program which is the role of leading the extention of using the space. That is why the program is important because it is effected directly to the way of using the space and the place of the furniture. I am looking forward that this study is the basic data for the planning of the public space in the complicated culture.

• Journal of The Korean Digital Architecture Interior Association
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• v.4 no.1
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• pp.17-25
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• 2004

The architectural space is the involuntary place where man lives and experiences, and as a 3 dimensional space through the continuous experience with the concept of 4th dimension of time, it provides the observers with the dramatic space imagery. These kinds of space experiences are experienced mentally and perceptively through the physical elements of inner and outer space of the architectural buildings, and this space imagery is created here by all the space composing elemensts of the building. These space experiences are caused by the changing processes of the space characteristics, and the observers perceive the changes in space characteristics. These changing processes of inner and outer space, space versus space, and unit space, which are perceived by the observer, could be called as 'the transition' and thd changes of the space characteristics as 'the transition characteristics'.

• Journal of The Korean Digital Architecture Interior Association
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• v.6 no.1
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• pp.13-23
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• 2006

The architectural space is the involuntary place where man lives and experiences, and as a 3 dimensional space through the continuous experience with the concept of 4th dimension of time, it provides the observers with the dramatic space imagery. These kinds of space experiences are experienced mentally and perceptively through the physical elements of inner and outer space of Museum, and this space imagery is created here by all the space composing elemensts of Museum. These space experiences are caused by the changing processes of the space characteristics, and the observers perceive the changes in space characteristics. These changing processes of inner and outer space, space versus space, and unit space, which are perceived by the observer, could be called as 'the transition' and the changes of the space characteristics as 'the transition characteristics'.

• Journal of The Korean Digital Architecture Interior Association
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• v.9 no.1
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• pp.19-29
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• 2009

The architectural space is the involuntary place where man lives and experiences, and as a 3 dimensional space through the continuous experience with the concept of 4th dimension of time, it provides the observers with the dramatic space imagery These kinds of space experiences are experienced mentally and perceptively through the physical elements of inner and outer space of the architectural buildings, and this space imagery is created here by all the space composing elemensts of the building. These space experiences are caused by the changing processes of the space characteristics, and the observers perceive the changes in space characteristics. The present building is going with Eco-Architecture. When 2008 sees the building,,Eco-Architecture design which hits appears. There is a possibility of seeing 16 kind types from that place. And From here examined the spatiality which is expressed. These changing processes of inner and outer space, space versus space, and unit space, which are perceived by the observer. It's way to help in architectural design and wishes.

• Journal of Korean Society of Transportation
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• v.23 no.8 s.86
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• pp.163-170
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• 2005

The paper has developed a methodology of calculating accessibility in bus network by using a space syntax technique. The purpose is an effective analysis of accessibility improvement before and after Seoul bus reorganization. Space syntax methodology has an advantage to calculate easily network connectivity and accessibility. However, it also has a weakness not to consider the distance and travel time for calculating accessibility. As a result, we have developed a hybrid of the space syntax methodology and the travel time measures. This method has been applied to evaluate the accessibility before and after the hierarchical bus systems introduced in Kangnam area of Seoul.

• Journal of Astronomy and Space Sciences
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• v.34 no.1
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• pp.7-17
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• 2017

In South Korea, there are about 80 Global Positioning System (GPS) monitoring stations providing total electron content (TEC) every 10 min, which can be accessed through Korea Astronomy and Space Science Institute (KASI) for scientific use. We applied the computerized ionospheric tomography (CIT) algorithm to the TEC dataset from this GPS network for monitoring the regional ionosphere over South Korea. The algorithm utilizes multiplicative algebraic reconstruction technique (MART) with an initial condition of the latest International Reference Ionosphere-2016 model (IRI-2016). In order to reduce the number of unknown variables, the vertical profiles of electron density are expressed with a linear combination of empirical orthonormal functions (EOFs) that were derived from the IRI empirical profiles. Although the number of receiver sites is much smaller than that of Japan, the CIT algorithm yielded reasonable structure of the ionosphere over South Korea. We verified the CIT results with NmF2 from ionosondes in Icheon and Jeju and also with GPS TEC at the center of South Korea. In addition, the total time required for CIT calculation was only about 5 min, enabling the exploration of the vertical ionospheric structure in near real time.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.3
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• pp.704-709
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• 1997

Space maintainers needs following extraction of primary molars, due to severe dental caries under general anesthesia. Delivery of conventional space maintainers has three of the disadvantages of the method, there being a impression taking and time consuming due to laboratory procedure, and delivery problem due to relaxed tongue. For this problem improved, modified space maintainer is prefabricated before procedure, and adjust, delivery in operation room, favorable results were obtained. The following results were obtained. 1. Delivery time is very reduced than conventional space maintainers. 2. After space maintainer delivery, follow check-up, without impingement of soft tissue, distortion of wire. After space maintainer delivery, continuous research is required so that space maintainer delivery is applied to usual dental treatment, and it is necessary of long term research.

• Journal of the Korean housing association
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• v.20 no.2
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• pp.101-108
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• 2009

The purpose of this study is to develop basic data for the design of the housing space for unit that factors in the sentiment of the residents by using aesthetic elements and expression method to search for the ways to design housing space for differentiated unit. The results are as follows: First, aesthetic elements in the aesthetic element in the unit housing space for unit can be classified into basic elements and detailed elements. Second, it is possible to classify into distortion, mixing, superposition and juxtaposition methods. Third, use of the 'material' for 'wall' is recommended when designing differentiated housing space by using basic elements. At this time, expression using the method of 'mixing' is effective for inducing differentiation. In particular, elements that can perceive the difference in time are mixed, to add on slight differentiation. Fourth, 'illumination' and 'material' are used when designing differentiated housing space by using detailed elements. Fifth, preference degree of the expression method is manifested differently depending on the selected elements. Lastly, this study conducted a study on the preference level of the aesthetic elements and expression method targeting the experts alone to differentiate the design of the residential space for unit.