• The Korean Journal of Quaternary Research
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• v.20 no.1 s.26
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• pp.9-27
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• 2006

The East Asian (China, Korea and Japan) summer monsoon precipitation and its variability are examined from the outputs of the 22 coupled climate models performing coordinated experiments leading to the Intergovernmental Panel on Climate Change Fourth Assessment Report (IPCC AR4) following the multi-model ensemble (MME) technique. Results are based on averages of all the available models. The shape of the annual cycle with maximum during the summer monsoon period is simulated by the coupled climate models. However, models fail to simulate the minimum peak in July which is associated with northward shifts of the Meiyu-Changma-Baiu precipitation band. The MME precipitation pattern is able to capture the spatial distribution of rainfall associated with the location of the north Pacific subtropical high and the Meiyu-Changma-Baiu frontal zone. However precipitation over the east coast of China, Korea-Japan peninsular and the adjoining oceanic regions is underestimated. Future projections to the radiative forcing of doubled $CO_2$ scenario are examined. The MME reveals an increase in precipitation varying from 5 to 10 %, with an average of 7.8 % over the East Asian region at the time of $CO_2$ doubling. However the increases are statistically significant only over the Korea-Japan peninsula and the adjoining north China region. The increase in precipitation may be attributed to the projected intensification of the subtropical high, and thus the associated influx of moist air from the Pacific to inland. The projected changes in the amount of precipitation are directly proportional to the changes in the strength of the subtropical high. Further a possible increase in the length of the summer monsoon precipitation period from late spring through early autumn is suggested.

• Korean Journal of Materials Research
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• v.7 no.3
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• pp.175-179
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• 1997

bliniaturization oi microwave circuit components is an important issue with the development in the mobile communication. Capacitors, inductors anti hybrid devices of these are building blocks of electric circuits, and the fabrication of these devices using thin film technology will influence on the miniaturization of electronic devices In this paper, we report the successful fabrication of the inductors, capacitors and LC hybrid devices using a ferroelectric and a ferromagnetic oxide thin iilm. Au, stable at high temperatures in oxidizing ambient, is patterned by lift-off process, and oxide thin films are deposited by ion beam sputtering and chemical vapor deposition. These devices are characterized by a network analyzer in 0.5-15GtIz range We got the inductance of 5nH, capacitance oi 10, 000 pF and resonant frequencies of $10^{6}-10^{9}Hz$.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.3
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• pp.180-198
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• 2019

In recent years, countries like Europe and Japan have been involved in many researches on the Low-Crested Structure (LCS) which is the method to protect beach erosion and it is regarded as an alternative to the submerged breakwaters, and compiled its results and released the design manual. In the past, studies on LCS have focused on two-dimensional wave transmission and calculating required weight of armor units, and these were mainly examined and discussed based on experiments. In this study, three-dimensional numerical analysis is performed on permeable LCS. The open-source CFD code olaFlow based on the Navier-Stokes momentum equations is applied to the numerical analysis, which is a strongly nonlinear analysis method that enables breaking and turbulence analysis. As a result, the distribution characteristics of the LCS such as water level, water flow, and turbulent kinetic energy were examined and discussed, then they were carefully compared and examined in the case of submerged breakwaters. The study results indicate that there is a difference between the flow patterns of longshore current near the shoreline, the spatial distribution of longshore and on-offshore directions of mean turbulent kinetic energy in case of submerged breakwaters and LCS. It is predicted that the difference in these results leads to the difference in sand movement.

• Journal of the Korean Regional Science Association
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• v.35 no.1
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• pp.3-18
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• 2019

Urban sprawl has been criticized due to its negative effects, including the encroachment of farmland and open spaces, the increase in traffic congestion and air pollution, the decline of central city, the decrease in social capital, and the unfairness of tax burdens on infrastructure and public services. This study measures urban sprawl in the capital region of South Korea where the characteristics of urban sprawl have been known to be different from those identified in the U.S. metropolitan areas. In particular, the study examines whether the capital region has experienced the decline of the central city with an expansion of low density residential development in suburban areas. Three measurements, the sprawl index with population density, the ratio of changes in urbanized areas to changes in population, and the population density gradient, were employed to measure urban sprawl, and GIS mapping and descriptive analysis were used to examine the central city decline and the characteristics of development patterns in suburban areas. The results show that the capital region of South Korea is moving to the American style sprawled development with the decline of the central city and an increase of single detached homes in suburban areas, implying that policy makers need to develop growth management strategies to prevent urban sprawl and its negative effects that many U.S. metropolitan areas have suffered from.

• Korean Journal of Heritage: History & Science
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• v.45 no.4
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• pp.74-91
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• 2012

This study puts its focus on Honjeon space which relatively small number of precedent studies chose as a subject of a study. The objective is to analyze Honjeon space's spatial relationship and palaces that consist Honjeon through analysis of spatial configuration and elements that affected construction of Honjeon space. The Royal Funeral, among other ceremonies of Joseon Dysnasty, carries religious characteristic along with functional and structural characteristics. By analyzing "National Five Rites", "Uigwe for the State Funeral 魂殿都監儀軌", and "Annals of Joseon Dynasty", the study organized elementary details about Honjeon space and surrounding spaces to determine the symbolism of Honjeon space's location at each palace and compared them to see if any systematical features existed between Honjeon spaces of each palace. Through this study, it was apparent the king mainly used Jaseongdang Hall of Gyeongbokgung in the early period of Joseon Dynasty and he mainly used Sunjeongjun of Changdeokgung while the queen used Munjeongjun of Changgyeonggung as the time reached the later period of Joseon Dynasty. Also in determination of Honjeon space, the study found that there were records of avoiding Pyeonjeon space in need for political space. The study also determined that places other than Pyeonjeon space was intended to be used for Honjeon space through the analysis which indicates that spaces that were initially used as Pyeonjun in the early Joseon Dynasty and simultaneously as Honjeon space were moved due to changes made in terms of theirs usages. Through the study, it could be also known that primary spaces of Honjeon was composed accordingly to "National Five Rites" and constant pattern of spaces existed among buildings near Honjeon which were arranged according to each palace's characteristic.

• Science of Emotion and Sensibility
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• v.21 no.4
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• pp.43-54
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• 2018

The aim of this study is to determine the effect of motion sickness on pupil rhythm. Sixteen volunteers of both genders (8 male, 8 female, mean age $25.67{\pm}2.43$ years) experienced VR contents in both 2D and HMD versions for 15 minutes, and their pupillary rhythms were compared. The irregular pattern of the pupillary rhythms, as demonstrated by increasing mean pupil diameter (mPD) and standard deviation of the pupil diameter (sPD), revealed motion sickness after experiencing HMD condition. The pupillary response is strongly related to the cognitive load, and the motion sickness can be interpreted as a change in the cognitive load caused by the increasing volume of visual information that must be processed and the conflict or inconsistency between different sensory modalities. The method proposed in this study could be a non-contact measurement method for the monitoring of motion sickness using a web-camera rather than previous sensor-based methods.

• Korean Journal of Environment and Ecology
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• v.36 no.2
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• pp.202-216
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• 2022

Animals exhibit certain behaviors and movement patterns as they react to their internal needs, external stimuli, and surrounding environments. They have a bounded range in which they mostly spend their time, and it is referred to as a home range. Based on the fact that the home range is a critical area for the survival and preservation of species, there has been a growing body of research on developing more precise home range estimation methods to use the estimated ranges as a ground for establishing an effective conservation policy since the early 1940s. Recent rapid advancements in telemetry technology that resulted in the presence of autocorrelation between locations with short time intervals revealed the limitations of the existing estimators. Many novel estimators have been developed to compensate for it by incorporating autocorrelation in calculating home ranges. However, studies on the animal home range are still in their early stage in Korea, and newly developed methodologies have not yet been adopted. Therefore, this study aims to introduce the foreign home range estimation methods and foster domestic research activities on home ranges. Firstly, we compared and contemplated seven estimators by categorizing them into geometrical and statistical methodologies and then divided them into estimators that assume independent observations and those that consider autocorrelation in each category. After that, the home ranges of black-tailed gulls (Larus crassirostris) were calculated using GPS tracking data for the month of June and derived home range estimators by applying the methodology introduced in this study. We analyzed and compared the results to discuss the strengths and weaknesses of each method. Lastly, we proposed a guideline that can help researchers choose an appropriate estimator for home range calculation based on the animal location data characteristics and analysis purpose.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.31-31
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• 2022

기후변화, 물 부족, 인구 증가와 도시화로 인한 물 수요 증가, 수질 악화, 노후화된 인프라와 같은 세계적인 물문제의 증가로 인해, 도시 물순환 시스템 관리는 더 큰 어려움을 겪고 있다. 취수, 도·송수, 정수처리, 배·급수, 용수 사용, 하수 집수, 하수 처리, 재이용 및 배출 과정을 포함하는 도시 물순환 시스템의 과정은 매우 에너지 집약적인 활동이며, 이와 같은 에너지 소비는 탄소 배출과 양의 직접적인 상관관계가 있다. 따라서 자원 관리 및 데이터 관리를 최적화하기 위해 넥서스 관점의 접근법이 도시 물순환 시스템에 점차적으로 도입되고 있는 추세이다. 도시 물순환 시스템 넥서스에서는 일반적으로 에너지 인텐시티로 표현되는 물을 위한 에너지를 이해하는 것이 중요하다. 에너지 인텐시티의 차이는 기후(연평균 강수량, 단기 기후 변동성, 기후패턴 등), 지리적 특징(표고차, 평지비, 위치 등), 시스템 특성(총급수량, 인구, 인구밀도, 관로 연장 등) 및 운영관리 효율(수압, 누수율, 에너지 효율 등)과 밀접한 관계가 있다. 그리고 도시 물순환 시스템에서 에너지 관리를 증진시킨 방안은 유지관리 효율 개선(물·에너지 관리전략, 물손실 관리, 수요 관리 및 수요 대응 등), 신기술 도입, 그리고 에너지 회수로 나누어진다. 본 연구에서는 기존 문헌의 자료를 분석하여 도시 물순환 시스템의 각 공정별 에너지 인텐시티를 분석하였으며, 시스템 다이나믹스를 적용하여 다양한 도시 여건(인구, lpcd, 누수율, 취수원, 에너지 인텐시티)에서 외부영향(기후변화, 도시화)과 운영효율 변동(운영효율 향상, 신시술 도입)에 따른 도시 물순환 시스템 내 자원 사용 및 이동을 분석하였다. 에너지 인텐시티는 전체 도시 물순환 시스템, 상수 시스템, 하수시스템에서 각각 2.334 kWh/m³, 1.029 kWh/m³, 1.024 kWh/m³를 나타내었으며, 용수사용, 담수화, 재이용 과정에서는 매우 높은 값이 나타났다. 에너지 인틴시티의 값은 외부 영향에 크게 좌우되는 것으로 분석되었으며, 운영효율의 변동에 따라서 물 및 에너지 사용량은 변화하였지만 에너지 인텐시티의 변동은 크지 않았다. 이에 따라 도시 물순환 시스템을 넥서스 관점에서 관리하기 위해서는 에너지 인텐시티 이외에 물 및 에너지 사용량, 유수수량 관점 에너지 인텐시티, 사용수량 관점 에너지 인텐시티를 종합적으로 고려하는 것이 필요하다.

• Information Systems Review
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• v.21 no.2
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• pp.1-27
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• 2019

It is possible to provide Smart Tourism Service through the development of information technology. It is necessary for the tourism industry to understand and utilize Big Data that has tourists' consumption patterns and service usage patterns in order to continuously create a new business model by converging with other industries. This study suggests to activate Jeju Smart Tourism by analyzing Big Data based on credit card usage records and location of tourists in Jeju. The results of the study show that First, the percentage of Chinese tourists visiting Jeju has decreased because of the effect of THAAD. Second, Consumption pattern of Chinese tourists is mostly occurring in the northern areas where airports and duty-free shops are located, while one in other regions is very low. The regional economy of Jeju City and Seogwipo City shows a overall stagnation, without changes in policy, existing consumption trends and growth rates will continue in line with regional characteristics. Third, we need a policy that young people flow into by building Jeju Multi-complex Mall where they can eat, drink, and go shopping at once because the number of young tourists and the price they spend are increasing. Furthermore, it is necessary to provide services for life-support related to weather, shopping, traffic, and facilities etc. through analyzing Wi-Fi usage location. Based on the results, we suggests the marketing strategies and public policies for understanding Jeju tourists' patterns and stimulating Jeju tourism industry.

• Information Systems Review
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• v.25 no.1
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• pp.75-91
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• 2023

Thanks to information technologies, sharing economy services offer a new way of consumption. Carsharing appeared as a novel type of service that transformed the conventional way of personal transportation, from owning a vehicle to using an on-demand service. Allowing users to use a vehicle without owning a car, carsharing provides various social benefits such as the reduction of resource allocation inefficiencies and the alleviation of transportation problems. To strengthen such positive aspects of carsharing service, it is essential to understand an individual's service usage pattern and reveal factors that affect users' reuse behavior. This study investigates the factors that have an influence on carsharing reuse of users applying RFMC (Recency, Frequency, Monetary, and Clumpiness) model, the popular model for understanding the reuse likelihood of customers. Using data from a leading carsharing service provider in South Korea, we empirically analyze the effect of RFMC on carsharing reuse behavior. The findings show that recency and monetary values are negatively related to reuse while frequency is positively related to carsharing service reuse. Moreover, the impact of recency and monetary value are more salient whereas the impact of frequency is smaller among users with higher clumpiness. Based on these findings, this study elaborates on theoretical and practical implications.