• 대한전자공학회논문지SD
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• 제46권10호
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• pp.40-45
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• 2009

본 논문에서는 사용자의 일상적인 동작 분석자료를 기반으로 실시간으로 사용자의 움직임 추정이 가능한 휴대형 센서 디바이스 및 활용 결과를 소개한다. 센서 디바이스는 3차원 가속센서와 GPS를 장착하고 있으며 센서 데이터 처리 및 움직임 추정을 위한 32비트 마이크로컨트롤러, 그리고 센서 데이터 및 추정결과를 전송하기 위한 블루투스 타입의 무선 통신 모듈을 포함한다. 완성된 디바이스는 50*47*14(mm)의 크기이며 리튬이온 소형 배터리 기준으로 연속 사용시 최대 10시간, 대기시간은 약 160시간 정도의 소형/저전력 형태로 구현되었다. 추정 가능한 사용자 움직임의 종류는 크게 3가지("서기", "달리기", "걷기")이며 피실험자군에 의한 동일 동작에 대한 가속센서 변화량을 학습하여 결정 트리 형식으로 사용자 움직임을 결정한다. 실험 결과 사용자 움직임 추정에 대한 정확도는 90% 이상인 것으로 확인되었다.

• 한국지형학회지
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• 제27권1호
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• pp.33-45
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• 2020

A number of unconsolidated deposits, consisting of a layer of gravels and silt, are found in Dangjeong-ri, Seocheon-gun in the western coast. From below in the stratigraphic sequence, the gravel layer ranging up to a maximum thickness of about 2 meters is interpreted as being formed by fluvial processes of an old channel (Dangjeong S.), and the overlying silt or sandy silt layer of 2 to 3 thickness meters is assumed to be emerged paleo-tidal sediments which was deposited in low tidal-energy environments. As the results of rock surface IRSL datings, the depositional ages of gravels are confirmed as ca. 78,000 ~ 83,000 years BP, indicating that the layer was formed in response to a high-stand sea level of MIS 5a along the Dangjeongcheon estuary. It is presumed that the relative height of 4.5 meter between the altitude of the stream bed (9.5 m) and the altitude of the bedrock boundary in the gravel layer (14 m) indicates the uplift amount since deposition. Paleo-sedimentary environments and an altitude of paleo-shoreline in the study area will be discussed with additional age dating focused on the silt layer.

• 천문학논총
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• 제37권3호
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• pp.59-79
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• 2022

We investigated the records of astronomical phenomena in the Hyeonjong-Donggung-Ilgi written by the educational office for a crown prince, Sigang-won, during the time of a crown prince of the king Hyeonjong (i.e., from 1649 to 1659). Of the total of 3,625 days, 3,044 astronomical accounts were compiled from astronomical records of 2,003 days. We classified these astronomical accounts into 16 items, grouped into five categories, and statistically analyzed each group. In our analysis, the accounts for atmos-pheric optical phenomena equates to 57.9% of the total, and for celestial phenomena visible during the daytime the percentage is 17.3%. The records related to the approach between two objects such as planets, moon, and stars account for 3.3%, and solar or lunar eclipses take up 0.6%. The ratio of accounts regarding meteor, comet, and fire light (火光) stand at 13.8%, 0.30%, and 6.8%, respectively. Sunny days account for 71.1% of all days per year during this period. We determined that the distribution of the fire light by month is similar to that of the solar halo. We also found that the astronomical records from the Annals of the Joseon Dynasty correspond to only 30% of those of the Hyeonjong-Donggung-Ilgi for the same period. In particular, the phenomena of celestial objects occurring outside the atmosphere are transmitted to the Annals of the Joseon Dynasty in a higher proportion than the phenomena inside the air. It is therefore necessary to use a historical diary like a Donggung-Ilgi to interpret the phenomena in the air such as atmospheric optical events, meteor, and fire light.

• 한국운동역학회지
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• 제15권3호
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• pp.143-152
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• 2005

The purpose of this study was to predict the failure or success of the Snatch-lifting trial as a consequence of the stand-up phase simulated in Kane's equation of motion that was effective for the dynamic analysis of multi-segment. This experiment was a case study in which one male athlete (age: 23yrs, height: 154.4cm, weight: 64.5kg) from K University was selected The system of a simulation included a multi-segment system that had one degree of freedom and one generalized coordinate for the shank segment angle. The reference frame was fixed by the Nonlinear Trans formation (NLT) method in order to set up a fixed Cartesian coordinate system in space. A weightlifter lifted a 90kg-barbell that was 75% of subject's maximum lifting capability (120kg). For this study, six cameras (Qualisys Proreflex MCU240s) and two force-plates (Kistler 9286AAs) were used for collecting data. The motion tracks of 11 land markers were attached on the major joints of the body and barbell. The sampling rates of cameras and force-plates were set up 100Hz and 1000Hz, respectively. Data were processed via the Qualisys Track manager (QTM) software. Landmark positions and force-plate amplitudes were simultaneously integrated by Qualisys system The coordinate data were filtered using a fourth-order Butterworth low pass filtering with an estimated optimum cut-off frequency of 9Hz calculated with Andrew & Yu's formula. The input data of the model were derived from experimental data processed in Matlab6.5 and the solution of a model made in Kane's method was solved in Matematica5.0. The conclusions were as follows; 1. The torque motor of the shank with 246Nm from this experiment could lift a maximum barbell weight (158.98kg) which was about 246 times as much as subject's body weight (64.5kg). 2. The torque motor with 166.5 Nm, simulated by angular displacement of the shank matched to the experimental result, could lift a maximum barbell weight (90kg) which was about 1.4 times as much as subject's body weight (64.5kg). 3. Comparing subject's maximum barbell weight (120kg) with a modeling maximum barbell weight (155.51kg) and with an experimental maximum barbell weight (90kg), the differences between these were about +35.7kg and -30kg. These results strongly suggest that if the maximum barbell weight is decided, coaches will be able to provide further knowledge and information to weightlifters for the performance improvement and then prevent injuries from training of weightlifters. It hopes to apply Kane's method to other sports skill as well as weightlifting to simulate its motion in the future study.

• 한국실내디자인학회논문집
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• 제18권2호
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• pp.50-60
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• 2009

The change of idea about overall politics, society, technology, and culture in 20th century led to the change of kitchen which is the central space of household affairs as well. Frankfurt kitchen of Margarete Schuette Lihotzky which was introduced for the first time at Germany International Trade Exhibition in 1927 functionally designed small space of $6.5m^2$ with considering move-line and convenience. This is the beginning of kitchen type which has built-in sink and cupboard that is regarded as an universal option these days, and this has extensively been applied to kitchen system throughout the world after the repetitive development in America, Sweden and Switzerland. And improved kitchen of Park Gil-Yong which was influenced by rationalism introduced from the house improvement campaign and the opening of a port which were progressed in Korea in $1919{\sim}1930$ is the first stand-up kitchen which improved the inefficiency of Korean conventional kitchen. The purpose of this study is to understand the change aspect of kitchen through the rationalization in each country by comparing the introduction background of the times, change of space for residence and kitchen, and the characteristics of kitchen plan which had influence at the turning point on the kitchen in Korea, Europe on the side of efficiency at the same period, take into consideration of our residing-culture which has rapidly been changed between tradition and modernity, and to see the direction of kitchen design which copes with the unique residential environment.

• 복식문화연구
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• 제13권6호통권59호
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• pp.919-933
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• 2005

This study goes into the field of CosPlay that takes place in Korea, and directly observes the people who engage in CosPlays. Based on in-depth interviews, this research identified the reasons why the CosPlay aficionados participate in this practice and their cultural preferences. Ethnography methodology was used to understand the behavior of the cultural entities of CosPlays. Moreover, this research attempted to understand their daily formalities through their own perspective and language instead of superficial language. In general, CosPlay form that they manifest is classified into two main categories: those who enjoy posing by becoming their favorite characters and those like to wear the clothes of their favorite characters and go up on the stage to perform an act of animation or game where the applicable character appears. Some of these groups are: 1) 'Bishojo CosPlay' that CosPlays mostly Bishojo cartoon characters and wants to just stand out, 2) 'Aekyo' group that CosPlays merely for the sake of the enjoyment of wearing costumes instead of having the mania-like characteristics, 3) 'CosPlayer Group' who enjoy doing organized team CosPlay in order to present a performance, 4) 'J-Rock CosPlay' group that CosPlay Japanese visual rock groups and prepare to be among a professional CosPlay team, and 5) 'People related to Cospre.com' who try to make CosPlay rooted in as one of new cultures.

• 한국항해항만학회지
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• 제47권2호
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• pp.106-119
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• 2023

Due to global decarbonization movement and tightening of maritime emissions restrictions, the shipping industry is going to switch to alternative fuels. Among candidates of alternative fuel, methanol is promising for decreasing SOx and CO2 emissions, resulting in minimum climate change and meeting the goal of green shipping. In this study, a novel combined system of direct methanol solid oxide fuel cells (SOFC), proton exchange membrane fuel cells (PEMFC), gas turbine (GT), and organic Rankine cycle (ORC) targeted for marine vessels was proposed. The SOFC is the main power generator of the system, whereas the GT and PEMFC could recover waste heat from the SOFC to generate useful power and increase waste heat utilizing efficiency of the system. Thermodynamics model of the combined system and each component were established and analyzed. Energy and exergy efficiencies of subsystems and the entire system were estimated with participation of the first and second laws of thermodynamics. The energy and exergy efficiencies of the overall multigeneration system were estimated to be 76.2% and 30.3%, respectively. The combination of GT and PEMFC increased the energy efficiency by 18.91% compared to the SOFC stand-alone system. By changing the methanol distribution ratio from 0.05 to 0.4, energy and exergy efficiencies decreased by 15.49% and 5.41%, respectively. During the starting up and maneuvering period of vessels, a quick response from the power supply system and propulsion plant is necessary. Utilization of PEMFC coupled with SOFC has remarkable meaning and benefits.

• Strategy21
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• 통권37호
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• pp.5-31
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• 2015

The Republic of Korean Navy (ROKN) started from scratch. However, ROKN demonstrated its Blue Navy capabilities successfully to the entire world by conducting "Operation Early Dawn" at the Aden Bay, Yemen in Jan 2011. On the event of the 70th anniversary of the ROKN, I would like to retrospect past gleaning from voyages and challenges we had in the past. At the very inception of the ROKN, Korean government as well as senior military leaders recognized that it had no time to spare to clean up military those were insinuated deeply by communist agents. It was the top priority of the government. The Mongumpo Operation which was not well known, conducted by ROKN was one of the clean-up drive. The Korean War sometimes called as "a fire from land put-off at the sea". The world famous "Incheon Landing" which reversed war situation from the Nakdong Perimeter also done by Sea Power. ROKN conducted various maritime operations including not only Incheon Landing, but amphibious operation at Hungnam, mine sweeping, sea convoy, Wonsan Withdrawal. On the same day of the Korean War started, 25th June 1950, unless the victory of the ROKNS Baekdusan (PC 701) at the Korean Strait, the waning lamp light of Korea could not be rekindled by the participation of the U.N. The ROKN rescued the 17th regiment of Korean Army from the isolation at the Ongjin Peninsular and transported gold and silver bars stored at the Bank of Korea to the Navy supply deposit in Jinhae safely. ROKN special intelligence unit conducted critical HUMINT which led Incheon Landing success. One of important mission ROKN conducted successfully was not only transporting war fighting materials but also U.S. provided grains to starving Koreans. ROKN participated Vietnam campaign from 1960s and conducted numerous maritime transportation operations supplying materials to Vietnam military forces along the long coastal lines. Experienced Naval Officers and enlisted men who discharged and acquired as merchant marine certificate supported most of the U.S. sea lift operations throughout the Vietnam campaign. ROK-US Combined Forces which had been honed and improved its war fighting capabilities through the Korean War and out of Vietnam jungle playing key deterrent against threat from north Korea. However, those threat level will be completely different when north Korea finish its nuclear weapon ambition. In order to stand firm against north Korean nuclear threat, I would like to expect strong political leadership supporting nuclear submarine for ROKN.

• 한국컴퓨터그래픽스학회논문지
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• 제2권1호
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• pp.48-60
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• 1996

이 논문은 실감나는 컴퓨터 그래픽 애니매이션을 하기위한 새로운 방법을 제시하는데, 이것은 forward dynamic simulation 과 비선형 방정식 해법을 사용한 것이다. 이 방법을 사용하여 시뮬래이션할 경우, 물리학적 기하학적 기구학적 제약을 쉽게 만족시킬 수 있다. 이러한 forward dynamic simulation 기법은 특히 비 자발적인 동작에 대하여 아주 실감나는 동작을 제공한다. 이러한 시뮬래이션 기법에 비선형 방정식 해법을 사용하여 컴퓨터 그래픽 애니매이션 기법을 만든다. 기본적인 방법은 동작 제어 기능을 추가하여 사용자가 애니매이션 하고자 하는 목적을 만족 시키는 것인데, 비선형 함수의 문제로 변환하여 최적값만 찾으면 되는 것이다. 이러한 forward dynamic simulation 을 사용한 애니매이션을 작동기를 가진 경우와, 작동기를 가지지 않은 경우로 나누어 두개의 제어방법을 제시하는데, 특히 선형 작동기(근육)를 가진 경우에 대하여 보다 현실에 가까운 제어법을 제시한다. 이상의 두 동작 제어에 관한 예를 "마술주사위" 와 "사람의 일어섬" 예로 보여준다.

• 한국작물학회지
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• 제41권spc1호
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• pp.123-144
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• 1996

This review deals briefly with the various medicinal components(mainly saikosaponins), their biological activities and the variation of their contents by different cultivation environment and plant parts in Bupleurum species. Bupleuri radix, a crude drug, is the root of Bupleurum falcatum L. (Korea, Japan), B. chinense(China), and their related species (Umbelliferae). There are over 120 species in Bupleurum genus throughout world, mainly Asian area, and over 5 species in Korea, investigated up to now. These plants contain many physiological active compounds and the principal components are saikosaponins. Major activities of this crude drug and saikosaponins are the anti-inflammatory and antihepatotoxic activities. Saikosaponins and their derivatives in Bupleurum spp. have been chemically studied, isolated and identified over 70 compounds in over 50 species. Other components, physiologically active ones, also have been investigated, which are the groups of lignan, flavonoid, essential oil, polyacetylene, polysaccharide, etc. Saikosaponins belong to the group of triterpenoid saponin chemotaxonomically and occur the accumulation and turnover in plant tissues through secondary metabolism, mevalonic acid pathway. The contents and kinds of saikosaponins and other components in Bupleurum spp. plants are various due to different species and growing environments, as the plant growth characters and yield are various. Most of medicinal plants as well as Bupleurum species are very useful as agricultural products and traditional medicines, and also are very valuable as genetic resources and natural products. So we need to collect, evaluate, preserve, and utilize various medicinal plants, and also to under-stand secondary metabolism and improve the breeding and cultivation techniques for the safe production of crude drugs with high quality and yielding.