• Journal of the Korea Society for Simulation
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• v.20 no.1
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• pp.51-59
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• 2011

This paper is concerned with locomotion of dog-like quadruped robots that can adapt to various terrains, mainly dealing with implementation methods and characteristics of static and dynamic gaits. To this end, a 12-DOF robot is built in house, motional trajectories of its body and feet are generated mimicking biological life, and the corresponding leg joint angles are analytically obtained by inverse kinematics. Such joint angle data are then applied to the robot's ADAMS model for computer simulations so that the planned walk and trot gaits are both confirmed dynamically stable. However, contrary to the simulation results, previous trot patterns showed unstable behavior during experiments. This problem led us to analyze the reason, and in the course we discovered the importance of maximally utilizing the concept of WSM rather than ZMP and therefore reducing the gait period to secure the stability of dynamic gaits such as trot.

• Journal of Korean Society of Archives and Records Management
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• v.18 no.2
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• pp.109-133
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• 2018

The need for the records management of administrative information dataset has led to a broad consensus among archivists and has been continuously studied. In the meantime, information technology has greatly advanced, and the development and redevelopment of information management systems have been increasing. Nevertheless, dataset management in information management system has not been practiced in public organizations. This is because it is supposed that no practical management plan exists. From the point of view that practical dataset management methods should be based on the reality of dataset creation and management environment, this study investigates various active datasets in working administrative information systems. The examples and the information drawn from the examination are expected to contribute to dataset management planning. Moreover, the research methods can be utilized in further studies.

• Journal of Digital Convergence
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• v.18 no.9
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• pp.343-349
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• 2020

This study is cases study of sustainable eco-friendly cosmetics packages. The importance of eco-friendly packages has been increasing as environmental issues have recently emerged around the world. Domestic cosmetics industry are releasing sustainable package designs with these changes, but they are limited. In this study, sustainable package criteria were divided and analyzed based on each of the five prior studies of domestic and foreign cases. Studies have confirmed that there is no diversity in the materials and designs of sustainable packages in Korea compared with other countries. Also, it could be seen that there was the lack of consumer-led eco-friendly campaigns. Starting point of research, it is expected that this study may help continue to study better sustainable cosmetics packages in the future.

• The korean journal of orthodontics
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• v.50 no.3
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• pp.206-215
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• 2020

Osteochondroma is a common benign tumor of bones, but it is rare in the mandibular condyle. With its outgrowth it manifests clinically as deviation of the mandible limitation of mouth opening, and facial asymmetry. After the tumor is diagnosed on the basis of clinical symptoms and radiographic examination including cone-beam computed tomography (CBCT) analysis, an appropriate surgery and treatment plan should be formulated. Herein, we present the case of a 44-year-old female patient who visited our dental hospital because her chin point had been deviating to the left side slowly but progressively over the last 3 years and she had difficulty masticating. Based on CBCT, she was diagnosed with skeletal Class III malocclusion accompanied by osteochondroma of the right mandibular condyle. Maxillary occlusal cant with the right side down was observed, but it was confirmed to be an extrusion of the molars associated with dental compensation. Therefore, after intrusion of the right molars with the use of temporary anchorage devices, sagittal split ramus osteotomy was used to remove the tumor and perform orthognathic surgery simultaneously. During 6 months after the surgery, continuous bone resorption and remodeling were observed in the condyle of the affected side, which led to a change in occlusion. During the postoperative orthodontic treatment, intrusive force and buccal torque were applied to the molars on the affected side, and a proper buccal overjet was created. After 18 months, CBCT revealed that the rate of bone absorption was continuously reduced, bone corticalization appeared, and good occlusion and a satisfying facial profile were achieved.

• Journal of Digital Convergence
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• v.15 no.3
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• pp.39-46
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• 2017

This study investigates the problems resulting from the Internet addiction policy management in South Korea and discusses a direction for rational policies by developing a system that facilitates interactive discussions among interest individuals and groups. The Korean society has experienced conflicts of interests among the government, the private sector and civil society in the policy. In addition, heightened competition among government ministries has led the Internet addiction policy management to be susceptible to how citizens respond to the claims of interested parties, thereby having the rationality of the policy management less count. To address these issues, this study investigates the current Internet addiction policy and explores the potential of new governance from a perspective of new institutionalism. This study suggests that the system of the Internet addiction policy should be restructured to transfer control over the policy from the central to local government and develop governance centered on the consensus of the government, the private sector, and civil society.

• Journal of architectural history
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• v.18 no.3
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• pp.7-25
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• 2009

Hakbongjongtaek(The head house of Uisong Kim family, 鶴峯宗宅), firstly built in the early 17th century, was moved to its neighboring place in the late 18th century. The man who led the relocation(移建) of the house was the eldest grandson of the family, Jong-soo, Kim. He made and overall plan and also participated in building the house. There remain four Gados(family paintings, 가도(家圖)) related to the relocation plan. This paper aims to make an analysis of these Gados, and through analysis, to find what was the essential poing of the relocation plan and how the point was represented in the paintings. The result of analysis is as follows: 1. The main focus of relocation plan was the form of Anchae(the inner house). Anchae was designed as asymmetrical form, and restricted to four kan. Only Andaechung needed to be 6 kan size for religious ceremonies. 2. For the design of Sarangchae, the displacement of large Sarangbang and small Sarangbang was an important issue. There were two ways of layout: parallel type and facing type. The latter was chosen. 3. The representation and techniques of Gado is quite concrete, in spite of differences among them. The expression of doors, windows, attic and kitchen was based on the understanding of space. Also the spatial division, which was expressed line on the grid, was based on the scaled ruler. As we've seen before, painting the relocation plan was a kind of endeavors to make the housing type as a realization of Garye. Also, we can find out that role of the eldest grandson of the family was quite important to carry out the plan. As well as, it was meaningful to examine Sadaebu (the aristocrat of Chosun)'s perception of housing.

• Journal of Navigation and Port Research
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• v.41 no.6
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• pp.409-414
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• 2017

In point of fact, there is a lack of explicit models that explain how services are perceived and evaluated by consumers who use them; present research on service quality has begun as a measure to complement this development. In this study, we applied the service quality model of PZB model based on Parasuraman et al.(1988) and the BNC model based on Brady and Cronin(2001), and compared the superiorities of each model. As a result of analyzing the questionnaire provided for terminal users, the BNC model is more superior than the PZB model. The increase in the number of factors led to an increase in the provided information, as a result of this, the model's explanatory power seems to be high. The results of this study may be different according to the characteristics of the industry, but we hope that the results presented in this study will lead to the expansion of the scope of research for the port loading and unloading business in the future.

• Journal of Satellite, Information and Communications
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• v.9 no.2
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• pp.85-90
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• 2014

In this paper, we propose a novel UE(User Equipment) position tracking algorithm of visible light signals, and analyze BER performance when optical beamforming scheme is applied in VLC(Visible Light Communications) system. The optical beamforming scheme as an interference mitigation method provides good optical channel conditions between UE(Rx) and LED light(Tx), and lead to better BER performance because UE is able to get a better RSSI(Received Signal strength indication) value. For the system BER, the proposed UE position tracking method for optical beamforming transmission demonstrates the performance enhancement compared to a system not applied the optical beamforming transmission scheme, and up to about 5~6dB SNR performance gain is achieved. The results of the paper can be applied to design of various VLC and LBS applications for ubiquitous home network systems.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.174-174
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• 2010

Gallium Nitride(GaN) attracts great attention due to their wide band gap energy (3.4eV), high thermal stability to the solid state lighting devices like LED, Laser diode, UV photo detector, spintronic devices, solar cells, sensors etc. Recently, researchers are interested in synthesis of polycrystalline and amorphous GaN which has also attracted towards optoelectronic device applications significantly. One of the alternatives to deposit GaN at low temperature is to use Single Source Molecular Percursor (SSP) which provides preformed Ga-N bonding. Moreover, our group succeeds in hybridization of SSP synthesized GaN with Single wall carbon nanotube which could be applicable in field emitting devices, hybrid LEDs and sensors. In this work, the GaN thin films were deposited on c-axis oriented sapphire substrate by MBE (Molecular Beam Epitaxy) using novel single source precursor of dimethyl gallium azido-tert-butylamine($Me_2Ga(N_3)NH_2C(CH_3)_3$) with additional source of ammonia. The surface morphology, structural and optical properties of GaN thin films were analyzed for the deposition in the temperature range of $600^{\circ}C$ to $750^{\circ}C$. Electrical properties of deposited thin films were carried out by four point probe technique and home made Hall effect measurement. The effect of ammonia on the crystallinity, microstructure and optical properties of as-deposited thin films are discussed briefly. The crystalline quality of GaN thin film was improved with substrate temperature as indicated by XRD rocking curve measurement. Photoluminescence measurement shows broad emission around 350nm-650nm which could be related to impurities or defects.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.5
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• pp.523-530
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• 2010

Recently more gravity data is being obtained due to the increased demands from the fields of geodesy, geophysics, and military. In general, the observed gravity values are corrected for the effect of tide, instrument drift, and instrument height to generate the absolute gravity values at a point. Until yet, the models for tide and drift corrections and those procedures are not determined in Korea which led to the inconsistent data processing for different data sets. Therefore, in this study, the models for tide and drift are analyzed to select the appropriate models. Based on the analysis, it was found that there is not much difference between Longman and Tamura tide models for celestial objects. Earth tide, however, should be considered in tide correction procedure. In drift corrections, the difference between the model considering only the common points and that considering all points appears significantly large up to 0.04mGal. In this case, the model with all points should be used as it the correct one according to the adjustment theory and it generates estimates with better precision.