• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.56.3-56.3
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• 2021

In a ΛCDM universe, most galaxies are believed to evolve by mergers and accretions. The debris resulting from such processes remains faint and/or diffuse structures, such as tidal streams and stellar halos. Although these structures are a good indicator of the recent mass assembly history of galaxies, they have the disadvantage of being difficult to observe due to their low surface brightness (LSB). To recover these LSB features by reducing the photometric uncertainties introduced by the optics system, we attempt to develop an optimized telescope, called a linear astigmatism free-three mirror system, that minimizes the loss and scattering of light within the telescope. With that prototype, we observe NGC 5907, known as a nearby galaxy with a fabulous loop structure(s), to inspect its performance. After a dedicated data reduction process, including flat-fielding with dark sky flat and sky subtraction, our observation reaches a 1σ surface brightness limit of μlim,r ≃ 28.3 mag arcsec-2 in 10×10 arcsec boxes. We finally identify a single tidal stream that is likely the remnant of a nearly disrupted galaxy. This finding emphasizes that the capability of LSB detection with our telescope is comparable to that of much larger telescopes.

• Journal of the Korean Society for Railway
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• v.19 no.6
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• pp.833-843
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• 2016

Recently, in the field of rail freight transportation, the number of trains dedicated for shippers has been increasing. These dedicated trains, which run on the basis of a contract with shippers, had been restricted to the transportation of containers, or so called block trains. Nowadays, such commodities have extended to cement, hard coal, etc. Most full freight cars are transported by dedicated trains. But, for empty car distribution, the efficiency still remains questionable because the distribution plan is manually developed by dispatchers. In this study, we investigated distribution models delineated in the KTOCS system which was developed by KORAIL as well as mathematical models considered in the state-of-the-art. The models are based on optimization models, especially the network flow model. Here we suggest a new optimization model with a framework of the column generation approach. The master problem can be formulated into a transportation problem with additional constraints. The master problem is improved by adding a new edge between the supply node and the demand node; this edge can be found using a simple shorted path in the time-space network. Finally, we applied our algorithm to the Korean freight train network and were able to find the total number of empty car kilometers decreased.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.237-240
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• 2005

Calibration and Validation are major element of any space borne Earth Observation Mission. These activities are the major objective of the commissioning phases but routine activities shall be maintained during the whole mission in order to maintain the quality of the product delivered to the users or at least to fully characterise the evolution with time of the product quality. With the launch of ERS-l in 1991, the European Space Agency decided to put in place a group dedicated to these activities, along with the daily monitoring of the product quality for anomaly detection and algorithm evolution. These four elements are all strongly linked together. Today this group is fully responsible for the monitoring of two ESA missions, ERS-2 and Envisat, for a total of 12 instruments of various types, preparing itself for the Earth Explorer series of five. other satellites (Cryosat, Goce, SMOS, ADM-Aeolus, Swarm) and at various levels in past and future Third Party Missions such as Landsat, J-ERS, ALOS and KOMPSAT. The Joint proposal by the European Union and the European Space Agency for a 'Global Monitoring for Environment and Security' project (GMES), triggers a review of the scope of these activities in a much wider framework than the handling of single missions with specific tools, methods and activities. Because of the global objective of this proposal, it is necessary to put in place Multi-Mission Calibration and Validation systems and procedures. GMES Calibration and Validation activities will rely on multi source data access, interoperability, long-term data preservation, and definition standards to facilitate the above objectives. The scope of this presentation is to give an overview of the current Calibration and Validation activities at ESA, and the planned evolution in the context of GMES.

• Journal of the Ergonomics Society of Korea
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• v.35 no.5
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• pp.425-437
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• 2016

Objective:The objective of this study is to develop an ergonomic toilet system along with constituent facilities that can be used with the front-entry sitting method when transferring from wheelchair to the toilet stool, instead of using the back-entry sitting method which is currently used. This system can offer more ease, convenience and safety for wheelchair users when using the restroom. Background: For users with disabilities, even a dedicated handicapped toilet requires maneuvering, especially when in a wheelchair. To transfer from wheelchair to the current back-entry sitting toilet, users need to get closer to the toilet and then turn or twist after erecting their body to get onto the toilet. This method induces inconvenience as well as secondary injury by falling when transferring to/from toilet. Method: To design a front-entry sitting toilet system, an ergonomics approach was applied which introduces a new design concept for people using wheelchairs. Using this toilet system, the wheelchair users don't need to turn or twist but can simply slide forward off the wheelchair directly onto the toilet stool in an easier and safer way. Results: The newly developed front-entry sitting toilet system is easier and safer for wheelchair users, and also space efficient requiring only two-thirds of the space of existing handicapped toilet. It is also usable by both individuals with disabilities and the general population. Conclusion: With the spread of the front-entry sitting toilet system developed in this study, wheelchair users can benefit from enhanced convenience and safety as well as significant restroom space savings. Additional effects can also be achieved such as improved self-esteem of people with disabilities by enabling to use the toilet on their own. Application: The newly developed front-entry sitting toilet system should enhance toilet accessibility to wheelchair users and the elderly. Introduction is needed with efforts at the national policy level and a macroscopic objective to promote the health and safety of the handicapped.

• Journal of the Korea Furniture Society
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• v.20 no.2
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• pp.166-174
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• 2009

Most of the furniture in the past was dedicated to its original use such as storage and accommodation of articles or sitting tools, but the concept of furniture in contemporary indoor spaces is gradually increasing in its meaning while exchanging close impacts with other spatial components. Indeed, in contemporary furniture, a component other than furniture constituting a space would sometimes serve the common roles of furniture or sometimes furniture would include all indoor objects used to make people's living more convenient. This study reviewed the meaning of furniture and changes in its roles in contemporary indoor spaces and summarized the characteristics presenting a few examples. First, in contemporary indoor spaces, furniture as an independent object does not having a meaning any more. The fusion of functions with other components constituting indoor spaces is the most important characteristics in contemporary furniture and it has been already attempted in diverse ways through fusion with buildings surpassing fusion with other pieces of furniture or electric home appliances. Second, the arrangement conforming to the roles required by spaces and diverse forms of attempts are essential. Since furniture is an item the most closely related to human residential life, studies on human behaviors in spaces must precede. The efforts to enhance work efficiencies and used limited spaces more efficiently will be continued and explorations of new forms should be also continued. Third, with regards to manufacturing methods, new technologies should be applied more widely and furniture materials must be diversified through the use of new materials including not only cutting-edge new materials but also all the materials that can be applied to furniture such as conventional natural materials and environment friendly materials that can be recycled.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.122.2-122.2
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• 2011

For more than a decade, NEA (Near-Earth Asteroid) survey teams equipped with 1 meter-class telescopes discovered thousands of NEAs in the northern sky. As of August 2011, some 8,200 NEAs have been cataloged, yet only five percent of them has been investigated for their physical and chemical properties. In order to improve current situation, we propose a deep ecliptic survey utilizing KMTNet, for detection and characterization of NEAs in the southern sky. Thanks to the wide-field capability (four square degrees) of the telescopes, we will be able to considerably expand the search volume carrying out precision photometry down to 21.5th magnitude. We plan to focus our survey on opposition and two "sweet spots" in the ecliptic belt. Since SDSS colors characterize mineralogical properties of NEAs, g', r', i', z' filters will be employed. Based on the round-the-clock observation, we will study their rotational properties; for multiple systems, mass, density and other physical parameters can be obtained. We plan to maintain a dedicated database of the physical and mineralogical properties of NEAs. With this archive, it is expected that our understanding on the population will see a drastic change. We also plan to participate in the GAIA Follow-Up Network for ground based observation of the Solar System Objects (GAIA-FUN-SSO). The follow- up astrometry will be performed upon alerts issued by the GAIA-FUN-SSO Central Node in France.

• Journal of the Korean Institute of Educational Facilities
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• v.25 no.1
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• pp.13-24
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• 2018

Planning and designing training facilities has been developed from educational facilities, and increasingly diversified society has raised a need for facilities dedicated to training and education in a differentiated space separate from the one for regular works. This particular need of our times has led to the expansion of training facilities nationwide although they have something to be desired when it comes to planning and designing with sustainability associated with the locational characteristics of urban space as well as the unique types of facilities taken into account. Against this backdrop, this study will examined a variety of training facilities that have been established since 2000 through theoretical review and conduct intensive analysis on the characteristics of the planning aspects to suggest their significance and implications and to present the overall meanings and ramifications of planning approaches in consideration of new challenges modern training facilities are faced with, which have been revealed through architectural design competitions in recent years. The relevant implications are as follows. First, one of the locational advantages of training facilities, which is commanding beautiful scenery of the surrounding area, can be considered as intent to stress the aspect of a resort, one of the functions of any training facilities. As this study has demonstrated, many training facilities are located near around a beach or a lake. Second, training facilities can be classified into three different types in terms of their location: urban, suburban and resort and such locational characteristics are directly related to intended programs and differentiated links with target users. Third, the architectural styles of training institutes are differentiated in terms of harmonious arrangement between beautiful natural scenery and buildings in consideration of the layout characteristics of major facilities and the distance of ramps in and out of the facilities along with architectural features, including the transparency of building elevation and the type of slopes of roof structure. Fourth, the individual lodging buildings feature a variety of types depending on the design concept with different roles depending on the directional aspects such as the connection of ramps and the relations with the outside. Fifth, outdoor space plans are differentiated according to the intended purpose of training facilities. When it comes to gym facilities, for example, different outdoor space plans are found to be made depending on the original design concept such as outdoor playground-centered planning or golf facilities.

• Journal of Service Research and Studies
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• v.12 no.3
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• pp.134-143
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• 2022

TThe National Cemetery is a space for realizing patriotism at the national level to honor the will of those who gave their lives for the country and to permanently venerate their loyalty and merit. The purpose of the establishment of the national cemetery is to imitate the spirit of patriotism that was sacrificed for the country and people. The state distinguishes between private death and public death as a sacrifice for the state. Furthermore, we carefully manage deaths that are classified as public. National cemeteries are the institutional space for managing such public deaths. With respect for devotion and discipline, the standards for burial and commemoration should not be based on status or class. In a national cemetery, shifting the degree of courtesy and priorities to devotion and discipline will become a true patriotism system in a democratic society. First of all, it is time to honor those who have died and those who have dedicated themselves to the restoration of national sovereignty as the highest and highest priority. This is the key to resolving the conflict that our national cemetery is experiencing and gaining public sympathy. This study is based on the premise that the national cemetery is insufficient as an open memorial space and historical space loved by the people. In addition, the implications and applicability of national cemeteries are reviewed through domestic and foreign excellent cases and high-quality and eco-friendly national cemetery construction cases in advanced countries.

• Convergence Security Journal
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• v.22 no.4
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• pp.11-16
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• 2022

Development of science technology make integrated CPS(Cyber-Physical System) appear. In CPS era, cyberspace and physical-space are hard to separate anymore, that is developing toward integrated CPS. The reality is not stopping, that is consistently changing and the concept of space is developing too. But several articles are considering for cyberspace and physical-space separately, and they are developing tailed alternative each case. The theorical approaching that is not considering reality is dwelled on past, and is dangerous from dropping down to floating cloud that is not considering progressed reality. This article is suggested to consider rimland theory to control measures in cyberspace. That is dedicated to integrated approaching from physical-space to cyberspace. And that is developing concreted controling measures in cyberspace. Especially, this article is suggested to policy alternative by analyzing north korea cyber warfare from rimland theory including human sources. Simplicity is the ultimate sophistication. This article make integrated approaching effects about cyberspace and physical-space to preparing in the CPS era.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.663-669
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• 2011

Since railway vehicle's improvements on speed and weight has caused interior noise, the passenger's convenience fell dramatically. Therefore many on-going researches are dedicated to reduce interior noise. In this study the analytical prediction of interior noise reduction has done through filling up the empty space using form and to modify the floor structure, which contributes highly with interior noises. Using Statistical Energy Analysis(SEA), the interior noise of the vehicles without the form filling on the floor structure and the vehicles with form filling and also a modified structure has been predicted. The selected percentage of form filling was 0, 50, 100% and through this research the analysis of noise reduction by form filling has been made. When floor structure has been filled with form, approximately 2 dB of noise reduction was observed and the difference of noise reduction level with 50 and 100% form filling was predicted to be very little. Through this study, the expectation of interior noise reduction in high speed trains is considered high.