• Journal of the Institute of Electronics Engineers of Korea CI
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• v.48 no.2
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• pp.106-116
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• 2011

USN(Ubiquitous Sensor Network) environment permits us to access whatever information we want, whenever we want. The technologies to provide a basement to these environments premise an accurate location establishment. Especially, ITS(Intelligent Transportation Systems) is easily constructed by applying USN technology. Localization can be categorized as either Range-based or Range-free. Range-based is known to be not suitable for the localization based on sensor network, because of the irregularity of radio propagation and the additional device requirement. The other side, Range-free is much appropriated for the resource constrained sensor network because it can actively locate by means of the communication radio. But, generally the location accuracy of Range-free is low. Especially, it is very low in a low-density environment. So, these two methods have both merits and demerits. Therefore, it requires a new method to be able to improve tracking accuracy by combining the two methods. This paper proposes the tracking scheme based on range-hybrid, which can markedly enhance tracking accuracy by effectively using the information of surrounding nodes and the RSSI(Received Signal Strength Indication) that does not require additional hardware. Additionally, we present a method, which can improve the accuracy of vehicle tracking by adopting the prediction mechanism. Simulation results show that our method outperforms other methods in the transportation simulation environment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.86-98
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• 2014

This study examined a long-standing issue with its perverse results in the Korean capital markets, such as any variant financial profiles over time, affecting capital structure for the firms belonging to the chaebols. It may be of interest to identify these components from the perspectives of international investors and domestic policy makers to implement their contingent strategies on the target leverage, since the U.S. financial turmoils in the late 2000s. Regarding the evidence from the three hypothesis tests on the firms in the chaebols, this research found that the control variabels measuring profitability, business risk, and non-debt tax shields, showed their statistically significant relationships with the different types of a debt ratio. While FCFF(free cash flow to the firm) showed its significant influence to discriminate between the firms in the chaebols and their counterparts, not belonging to the chaebols, BDRELY as the ratio of liabilities to total assets, comprising the enhanced 'Dupont' system, only showed its statistically significant effect on leverage in the context of the parametric and nonparametric tests. In line with the results obtained from the present research, one may expect that a firm in the Korean chaebol, may control or restructure its present level of capital structure to revert to its target optimal capital structure towards maximizing the shareholders' wealth.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.256-263
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• 2014

This research aims is to confirm the influence of a teacher's teaching style and teaching career on instructional analysis. Through this, the differences in the relevant elements' view points on a class and those in teachers' analysis view points on class criticism and instructional analysis at the education field can be investigated. For this study, the teaching styles of 198 elementary school teachers were categorized, their teaching careers were checked as teaching career and set them as covariate, and the differences in the view points on the analysis of the class climates were verified depending on each teaching style. As the research result, meaningful differences were found in four areas of the elements of class climates analysis, that is, creativity, vitality, precision, and gentleness. In the analysis of the class climates, the teachers with a professional style among the teaching styles gave the highest grades to creativity in the same class, those with a facilitating style to vitality, those with a role model style to precision, and those with a facilitating and role model style to gentleness. On the other hand, those with an authoritative and a delegating style were proved to give the lowest grades in general class climates. It means that teachers with different teaching styles have different viewpoints when analyzing a class, and those with a professional, a role model and a facilitating style have a relatively stronger intention to analyze a class through reflective introspection and permissive recognition.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4543-4550
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• 2012

The purpose of this paper is to suggest the improvement method to achieve the interactive development effect between high-tech industrial complex and its surrounding areas. For this reason, this paper has conducted an empirical analysis to find out relevant comprehensive factors, affecting nearby housing prices from such plans, especially by reviewing 'Seoul Digital Industrial Complex.' This paper is truly differentiated from previous research by adding a new perspective 'diverse location characteristics', as it focuses not only on 'high-tech facility' characteristics, but also on 'urban function facilities', including 'transportation facilities', 'amenity facilities', 'security facilities', etc. Then, SPSS Version 18.0 was utilized to conduct the multiple regression analysis with the accumulated relevant data and several results were drawn out as following: Firstly, 'deterioration level', 'brand of apartment', etc. are found to be major influencing factors. Secondly, 'educational facilities', 'transportation facilities', 'Cultural & Sports facilities', 'Amenity facilities', etc. are found in the sector of 'location characteristic'. Lastly, 'leading companies within the industrial complex', were also found, affecting nearby housing prices. Therefore, when a housing development project is planned to grant the interactive development effect to high-tech industrial complex and its surrounding housing areas, it is necessary to consider variety factors, such as comprehensive location characteristics and housing complex characteristics, and also proper housing policy measures should be devised in accordance with the actual demand of employees and their dependant family members.

• The Journal of the Korea Contents Association
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• v.12 no.10
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• pp.1-10
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• 2012

Many statistical methods have been adapted for terminology recognition to improve its accuracy. However, since previous studies have been carried out in a single core or a single machine, they have difficulties in real-time analysing explosively increasing documents. In this study, the task where bottlenecks occur in the process of terminology recognition is classified into linguistic processing in the process of 'candidate terminology extraction' and collection of statistical information in the process of 'terminology weight assignment'. A terminology recognition system is implemented and experimented to address each task by means of the distributed parallel processing-based MapReduce. The experiments were performed in two ways; the first experiment result revealed that distributed parallel processing by means of 12 nodes improves processing speed by 11.27 times as compared to the case of using a single machine and the second experiment was carried out on 1) default environment, 2) multiple reducers, 3) combiner, and 4) the combination of 2)and 3), and the use of 3) showed the best performance. Our terminology recognition system contributes to speed up knowledge extraction of large scale science and technology documents.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.468-474
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• 2020

The aim of this study was to compare the effect of a horseback riding simulator, Slings and Kendall Exercise on a cranio-vertebral angle and the neck pain of the Forward Head Posture. This study included 30 young people with forward head posture. They were randomly divided into three groups. Each group performed the exercises for six weeks three times a week from September 2018 to November 2018. The variations of cranio-vertebral angle and neck pain were analyzed using paired t-tests and a one-way ANOVA test. The results of the study are as follows. Three groups showed significant variations of cranio-vertebral angle and neck pain (p < 0.05). But comparison of cranio-vertebral angle and neck pain between the groups showed no significant difference (p > 0.05). This study found that each exercise group for forward head posture was effective for inducing normal cervical alignment and neck pain relief. Therefore, various exercises can improve the forward head posture.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.309-316
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• 2020

The aim of this study was to identify the relationship between smartphone usage time and oral health among Korean adolescents using data from the 13th (2017) Korea Youth Health Behavior Survey, which included 62,276 subjects. The daily smartphone usage time was categorized as not used, less than 2 hours, more than 2 hours, less than 4 hours, and more than 4 hours. Our results reveal that 60.1% of participants and 61.7% of smartphone users experienced oral disease symptoms annually, 27.4% of total adolescents used smartphone more than 4 hours daily during weekdays, and 53.8% more than 4 hours daily on weekends. The results from multivariate logistic regression analysis adjusting general characteristics show that the adjusted odds ratio (aOR) for risk of oral disease experience was 1.78 (95% confidence interval, CI 1.67-1.91) times higher in the group that used smartphones more than 4 hours a day on weekdays and 1.81 (95% CI 1.70-1.93) times higher in the group that used smartphones more than 4 hours a day on weekends compared to the group that did not use smartphones. The results indicate that smartphone overuse among Korean adolescents has a harmful effect on oral health. Education programs for reducing excessive use of smartphones among adolescents will help promote oral health.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.584-591
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• 2020

Reliability is an important factor in weapons systems. Low reliability causes the weapons system to fail to function properly, which directly leads to the weakening of combat capability. This paper classifies the structure of the 5.56 mm rifle, which is currently used by the Korean army, into a total of seven assemblies and describes the eight functions necessary for the rifle to operate normally. In addition, the concept of reliability was defined as the MRBF, and the Poisson process model and TTT plot were explained as a reliability analysis theory for the repair function system. Next, the field-data obtained by defining failure as the replacement of parts other than periodic exchange of parts were refined, and the reliability was analyzed by entering the refined field operation specifications into the Minitab program. As a result, the reliability of the rifle was determined to be 251.73. The assembly parts that required improvement was identified as the barrel, lower body, and butt stock assembly, and 10 detailed parts needed to be improved. Finally, the limits of the reliability analysis using the field-data currently available for small caliber firearms were considered.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.3
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• pp.132-145
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• 2020

By coming of the 4th industrial revolution era, HD map have became a key infrastructure for determining precise location of autonomous driving in areas of futuristic cars, logistics and robots. Autonomous vehicles have became more dependent on HD map to determine the exact location of objects detected by various sensors such as LiDAR, GNSS, Radar, and stereo cameras as well as self-location decisions. By actualizing autonomous driving and C-ITS technologies, the demand for precise information on HD map have increased. And also the demand for the creation of new information based on the convergence of various changes and real-time information have increased. In this study, domestic and international HD map standards and related environments have analyzed. Based on this, usability has researched which comparison with standard HD map established by various institutions. Additionally, usability of standard HD map have studied for applying actual autonomous vehicles by reworking HD map. By the result of study, standard HD map have well established to use by various institutions. If further research about layer classification and definition by institutions will carried out based on this study, it has expected that and efficient establishment and renewal of HD map will take place.

• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.1
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• pp.59-72
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• 2011

The research of psychological supporting systems as safety and welfare for disaster victims damaged psychologically as well as physically by a sudden disaster to return to effectively their social life has been carried. The domestic National Emergency Management Agency(NEMA) is operating the Disaster Victim Psychology Support Center that helps with curing damaged psychology and studies the transmission system of psychology management services, the classification of victims for disaster psychology support, and emergency consultation method to systemically support disaster psychology management. However, current psychology supporting centers provide the simple information for supporting centers such as medical and social welfare organizations. The development research of IT-based management systems to obtain needed information to construct the proposed systems curing psychological damage is still primitive step. Therefore, this paper shall propose a GIS-based integrated management system for victims and managers to effectively share related information one another and to return to victims' social life as soon as possible. Also, we implement a simple prototype system based on the Web. The proposed system supports the spatial search and statistical analysis based on map as well as keyword search, because having the location information on disaster victims, damage occurrence places, welfare and medical institutions, and psychological supporting centers. In addition, this system has the advantage reducing the frequency of disaster damage by providing aids in making efficient policy systems for the managers.