• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.8
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• pp.648-659
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• 2018

In this study, both the altitude error due to the refraction and the range error due to the delay in the ionosphere with respect to the frequency are extracted according to the radar elevation to analyze the effect of atmosphere on the space surveillance radar. To achieve this, the radio refractivity profile is modeled using the measured data from domestic weather stations. Then, the altitude-error due to the refraction is extracted using the ray tracing method, and the range error in the ionosphere is extracted according to the frequency. Further, considerations for radar design with respect to the radar error characteristics are discussed based on the abroad space surveillance radar and proposed domestic space surveillance radar. This analysis of the error characteristics is expected to be utilized for the determination of radar location, range of steering, and frequency in the space surveillance radar design.

• Journal of Astronomy and Space Sciences
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• v.28 no.3
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• pp.193-201
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• 2011

A strategy for geostationary orbit (or geostationary earth orbit [GEO]) surveillance based on optical angular observations is presented in this study. For the dynamic model, precise analytical orbit model developed by Lee et al. (1997) is used to improve computation performance and the unscented Kalman filer (UKF) is applied as a real-time filtering method. The UKF is known to perform well under highly nonlinear conditions such as surveillance in this study. The strategy that combines the analytical orbit propagation model and the UKF is tested for various conditions like different level of initial error and different level of measurement noise. The dependencies on observation interval and number of ground station are also tested. The test results shows that the GEO orbit determination based on the UKF and the analytical orbit model can be applied to GEO orbit tracking and surveillance effectively.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.3
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• pp.214-224
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• 2018

Continuous space development increases the occurrence probability of space hazards such as collapse of a satellite and collision between a satellite and space debris. In Korea, a space surveillance network with optical system has been developed; however, the radar technology for an independent space surveillance needs to be secured. Herein, an L-band phased array radar system for the detection and tracking of space objects is proposed to provide a number of services including collision avoidance and the prediction of re-entry events. With the mission analysis of space surveillance and the case analysis of foreign advanced radar systems, the radar parameters are defined and designed. The proposed radar system is able to detect a debris having a diameter of 10 cm at a maximum distance of 1,576 km. In addition, we confirmed the possibility of using the space surveillance mission for domestic satellites through the analysis of the detection area.

• The Journal of Sustainable Design and Educational Environment Research
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• v.11 no.1
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• pp.23-31
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• 2012

The number of school crime has grown continuously for last ten years and its intensity also has reached to serious condition. The concept of CPTED(Crime Prevention through Environmental Design) needs to be focused for improving school environment regarding this context. The exterior space of school environment is variously exposed to school crimes committed by colleague students and also intruders. From the perspective of school CPTED, Natural surveillance as one of the practical strategies requires the micro-scale analysis which clarifies local visibility at each different school exterior space. Thus, the purpose of this research is to develop the analysis method clarifying visibility condition at exterior space of school environment, which supports finding the condition of natural surveillance. The programmed analysis algorithm generated quantitative results clarifying Degree for static visibility and Clustering Coefficient for user tracking visibility. The result of this study produced the analysis method feasible to clarify weak natural surveillance conditions at school exterior spaces. Also, it is expected that the developed analysis method will be used to improve the layout of school exterior space from the perspective of CPTED.

• Journal of the Korean housing association
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• v.25 no.1
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• pp.23-32
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• 2014

This research progressed space evaluation test with 3D simulation for exterior space of detached housing area among the Seoul spaces of child sex offense in 2010. Based on changing analysis on natural surveillance by spatial changes of each physical element, the purpose is to suggest effective construction planning measure for preventing child sex offense. The results of research are as follows. First, natural surveillance of space's height differences and width differences were compared and analyzed. As the result, footpath shows that stairs of slope didn't make lots of effects on visual block, not block of spatial moving, because of the difference of stair height. Also, in case of parking space, visual connection with footpath is expanded when designing pilotis rather than heightening floor height, so activities of exterior people could be seen more easily. Therefore, natural surveillance was higher. Second, natural surveillance of architectural elements by changes of footpath' width was compared and analyzed. As the result, openness of footpath should be secured rather than openness of architectural element. And, planning autonomy of architectural form could be more expanded when securing openness of footpath.

• Korean Institute of Interior Design Journal
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• v.22 no.2
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• pp.211-219
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• 2013

The purpose of this study is to propose the environmental planning guidelines of elementary school settings for a crime safety. The research methodologies To achieve the goal, the literature review analysis and the survey were used as main research methodologies. The survey is organized as follows. First, elementary education facilities were divided into 20 spaces based on the major space. Second, after analyzing the domestic and foreign CPTED Guidelines, elements of environmental planning were classified to fit in the space. Based on this, the expert survey was conducted. The results of this study are as follows; First, it is necessary to consider specific places such as 'toilets', 'parking lot', 'in-between space', 'main access road', 'sub-access road' and 'harmful facilities around school' for safer school environment. Second, it is significant to plan 'equipment facilities' and 'outdoor space in the school setting' with priority for elementary education environment. Third, environmental planning elements for safer elementary schools can be classified into 9 factors(types) including 'natural surveillance planning', 'territoriality reinforcement planning', 'mechanical surveillance planning', 'access control planning' and 'neighborhood reinforcement planning'. Forth, regarding 'indoor space', crime-free elementary school environment can be build through 'natural surveillance planning' and 'territoriality reinforcement planning'. Finally, regarding 'outdoor space', the crime can be prevented through 'natural surveillance planning' and 'access control planning'.

• Korean Institute of Interior Design Journal
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• no.25
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• pp.103-110
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• 2000

The material world around human is normally composed of opaque one, with which human has made the spaces. The opaque material to make space has played a role to control the relationship among people and has produced socio-cultural things since the history started. The opening of opaque material(wall) connects one space with the other. Therefore, the meaning of opening is a connection among people who are in different spaces in terms of sociology. In conjunction with this, socio-cultural situation has been deployed differently. In the traditional european domestic space, the glass has been applied to this opening since they found the glass. It disconnects two spaces physically but connects them visually. Therefore, without blocking the opening visually, the glass became to protect people with their interior space from outside environment. The important thing is that the application of the glass in a building had been restricted because of opening size. However, after Industrial Revolution with the advanced technology of architecture, the glass came to be applied to the building and it became widen. So, the concept of glass window became to be the one of glass wall. This change made a transformation of visual character between two spaces which are separated with glass wall. This means that the glass wall gave two directional visibility while the glass window gave one directional visibility from inside to outside of space. This is because the amount of the natural light to the interior space increased due to widen glass in a space. This gave a change of visual authority and the space of surveillance(interior space) became to the one of communication. The space of surveillance, Michel Foucault mentioned in his book surveillance and punishment, is a very private one that is not visually permeable from the people outside, while the space of communication is a public one which needs other eyes. In the space of publicity, there needs a rationality, morality and ethics because of public surveillance and in the space of privacy, there restores a desire for sex and assaults.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.5
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• pp.447-454
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• 2016

Increase of space debris makes low earth orbit(LEO) environment more complex day by day and space situation Awareness(SSA) is becoming more important. As an essential part of SSA, space object surveillance and tracking is studied by many countries including America and Europe. And radar system forms the backbone of an space surveillance and tracking. Currently, Korea operates many LEO satellites like KOMPSAT but does not have dedicated radar systems which provide collision surveillance between satellite and space debris. Korea Aerospace Research Institute(KARI) NARO space center operates launch-vehicle tracking radar system in GOHEUNG and JEJU, respectively. In this paper, we describe developing operation concept to track International Space Station(ISS) using NARO radar and results of tracking. Then, we describe ISS orbit determination using radar tracking data. Lastly, orbit determination result is compares with TLE for analyzing effectiveness of orbit determination.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.32 no.2
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• pp.153-162
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• 2014

As CCTVs are widely utilized in diverse fields, many researchers have continuously studied to improve the surveillance performances of a CCTV system. However, an quantitative evaluation approach about the surveillance performance has rarely been researched. Therefore, we set up the research for suggesting a quantitative evaluation approach to determine the effectiveness of CCTV coverages. We firstly defined the surveillance resolution as that varies according to object's positions and orientations. Based on the definition, we computed surveillance resolution values at all three-dimensional positions with the orientations of interests in the specified space. By comparing these values to the required reasonable resolution, we determined the surveillance performance index indicating how well a CCTV system monitor a target space for specific surveillance objectives. This proposed approach evaluates the surveillance performance of a CCTV system quantitatively, so as examines the CCTV system design before its installation based on precise 3D spatial analysis.

• Convergence Security Journal
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• v.14 no.2
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• pp.73-79
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• 2014

In the 21st century, the higher CCTV, hidden Camera, and surveillance and contra-surveillance in Cyber-space are, the higher the voices of concern about surveillance society nationally are. Nevertheless, phenomenon of panoptisme is becoming into general use. Actually, this watching system should be on the rise but this is the output playing up and advertising the positive effect of immediate convenience and offering safety that government and business made. Thus, this study wants to offer implication to warn the invasion of privacy and generalization controlled society as pointed out cause and problem of the surveillance society time according to the digital era.