• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년 영문 학술대회
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• pp.283-292
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• 2008

The foremost criterion in the design of a Satellite Launch Vehicle(SLV) is its performance capability to boost the designated payload to the desired mission orbit; it starts from focusing on the SLV configuration to achieve the velocity requirements($}\Delta}V$) for the mission. In this paper we review an analytical approach which is suitable enough for preliminary conceptual design and is used previously to optimize stage configurations for Two Stage to Orbit SLV for Low Earth Orbit(LEO) Missions; we have extended this approach to Three Stage to Orbit SLV and compared different propellant options for the mission. The objective is to minimize the Gross Lift off Weight(GLOW). The primary performance figures of merit were the total inert weight of the SLV and the payload weight that the SLV could lift into LEO, given candidate propulsion systems. The optimization is achieved by configuring the $}\Delta}V$ between stages. A comparison of configurations of single-stage and multi-stage SLVs is made for different propellants. Based upon the optimized stage configurations a comparative performance analysis is made between Liquid and Solid fueled SLV. A 3 degree of freedom trajectory-analysis program is modeled in SIMULINK and used to conduct the performance analysis. Furthermore, a cost analysis is performed on our stage optimized SLVs. The cost estimation relationships(CER) used give us a comparison of development and fabrication costs for the Liquid vs. Solid fueled SLV in man years. The pros and cons of the production, operation ability, performance, responsiveness, logistics, price, shelf life, storage etc of both Solid and Liquid fueled SLVs are discussed. The statistics and data are used from existing or historical(real) SLV stages.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2001년도 The Pacific Aisan Confrence On Intelligent Systems 2001
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• pp.145-150
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• 2001

A Controlled Ecological Life Support System(CELSS) is essential for man to live a long time in a closed space such as a lunar base or a mars base. Such a system may be an extremely complex system that has a lot of facilities and circulates multiple substances,. Therefore, it is very difficult task to control the whole CELSS. Thus by regarding facilities constituting the CELSS as agents and regarding the status and action as information, the whole CELSS can be treated as multi-agent system(MAS). If a CELSS can be regarded as MAS the CELSS can have three advantages with the MAS. First the MAS need not have a central computer. Second the expendability of the CELSS increases. Third, its fault tolerance rises. However it is difficult to describe the cooperation protocol among agents for MAS. Therefore in this study we propose to apply reinforcement learning (RL), because RL enables and agent to acquire a control rule automatically. To prove that MAS and RL are effective methods. we have created the system in Java, which easily gives a distributed environment that is the characteristics feature of an agent. In this paper, we report the simulation results for material circulation control of the CELSS by the MAS and RL.

• 대한예방한의학회지
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• 제17권2호
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• pp.1-16
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• 2013

Environmental medicine has interest in the effect of natural environment on the human health. Nature is usually understoodas' sky(天)' and 'earth(地)' which implies the harmony of humankind and nature(天地相應). As can be shown above, environment concept is the basic in Korean Medicine which originate in "Huangdi's Internal Classic" as clear medical form. According to "Huangdi's Internal Classic" man ought to abide by the nurturing 'Tao(道)' which is the way of life. This can be explained as the principle of balance, specially of yin(陰) and yang(陽) as is represented by the transformation of the energies from the universe. Life through the four seasons is also referred in the classic upon when four different climates have some effect on people, and the regional effect on health is also written there. Under the strict modem view, the achievement of the classic in the field of environmental medicine may be treated as primitive, but it was induced through long-term observation, so that once was state-of-the-art result at that time. But to solve the intrinsic weak points in traditional environmental medicine and also to harmonize with modern science to contribute to national health, the way of modem research can be applied to traditional concept on environmental medicine. Natural scientific approach is to avoid superstition and incantation. Strict method approach is to enhance accuracy and reliance in clinical observation. Overall, predictability can help develop the effectiveness and efficiency of diagnosis, treatment, recurrence, and prevention in environmental disease with holy method of Korean Medicine.

• 한국한의학연구원논문집
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• 제2권1호
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• pp.1-25
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• 1996

The purpose of this paper is to study the basic medicine of the Gojoseon(古朝鮮) dynasty, especially 5 fields which are the theory of yin-yang(陰陽論), the theory of 5 progressive phasis(五行論), the theory of mind-body(心身論), Seon-gyo(仙敎), acupuncture(鍼術). The theory of yin-yang can be studied in the point of contents of it, not the name of it. Whan-in(桓因) is the god of sky, Woong(熊) is the god of earth. Whan-woong(桓雄), who is the son of Whan-in(桓因), came down from the sky, turned into a man. Woong(熊) lived in the cave, eating garlic and wormwood for 21days, got out of it and turned into a woman. The changes occurred by the mutual aid of Whan-woong and Woong. The theory of 5 progressive phasis can be founded in the archery. The bow and arrow is made of cucumber, horn and ligament of cow, glue made from airbladders of sciaenoid fish, which belong to mock(木). Beejeongbeepal(非丁非八) and make strong one's abdomen(腹實) belong ti soo(水), empty out one's chest(胞虛) belongs to whar(畵), thrusting(前推泰山) belongs to mock(木), shooting(發如虎尾) belongs to geom(金). Basically mind and body have no differance. Mind without body does not exist. Exocism excites the exorcist to the condition of whar(火). There are 3 parts, as treaLment, prevent, regimen, in the medicine. 2 parts as idealism and realism are in regimen. Seon-gyo(仙敎) belongs to the idealism of regimen. In China, is became Taoism(仙敎) later The art of accupunture was developed in the Gulf of pohair(渤海灣).

• Current Photovoltaic Research
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• 제6권1호
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• pp.21-26
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• 2018

Beside several advantages, the PV power generation as a clean energy source, is still below the supply level due to high power generation cost. Therefore, the interest in fabricating low-cost thin film solar cells is increasing continuously. $Cu_2O$, a low cost photovoltaic material, has a wide direct band gap of ~2.1 eV has along with the high theoretical energy conversion efficiency of about 20%. On the other hand, it has other benefits such as earth-abundance, low cost, non-toxic, high carrier mobility ($100cm^2/Vs$). In spite of these various advantages, the efficiency of $Cu_2O$ based solar cells is still significantly lower than the theoretical limit as reported in several literatures. One of the reasons behind the low efficiency of $Cu_2O$ solar cells can be the formation of CuO layer due to atmospheric surface oxidation of $Cu_2O$ absorber layer. In this work, atomic layer deposition method was used to remove the CuO layer that formed on $Cu_2O$ surface. First, $Cu_2O$ absorber layer was deposited by electrodeposition. On top of it buffer (ZnO) and TCO (AZO) layers were deposited by atomic layer deposition and rf-magnetron sputtering respectively. We fabricated the cells with a change in the deposition temperature of buffer layer ranging between $80^{\circ}C$ to $140^{\circ}C$. Finally, we compared the performance of fabricated solar cells, and studied the influence of buffer layer deposition temperature on $Cu_2O$ based solar cells by J-V and XPS measurements.

• Wind and Structures
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• 제36권3호
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• pp.201-213
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• 2023

In this study, the effect of sea surface temperature (SST) on the distribution of vertical wind speed in the atmospheric boundary layer of coastal areas was analyzed. In general, coastal areas are known to be more susceptible to various meteorological factors than inland areas due to interannual changes in sea surface temperature. Therefore, the purpose of this study is to analyze the relationship between sea surface temperature (ERA5) and wind resource data based on the meteorological mast of Høvsøre, the test bed area of the onshore wind farm in the coastal area of Denmark. In addition, the possibility of coastal disasters caused by abnormal vertical wind shear due to changes in sea surface temperature was also analyzed. According to the analysis of the correlation between the wind resource data at met mast and the sea surface temperature by ERA5, the wind speed from the sea and the vertical wind shear are stronger than from the inland, and are vulnerable to seasonal sea surface temperature fluctuations. In particular, the abnormal vertical wind shear, in which only the lower wind speed was strengthened and appeared in the form of a nose, mainly appeared in winter when the atmosphere was near-neutral or stable, and all occurred when the wind blows from the sea. This phenomenon usually occurred when there was a sudden change in sea surface temperature within a short period of time.

• 한국정보통신학회논문지
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• 제15권1호
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• pp.16-21
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• 2011

지상 또는 해상에서 주로 이루어지고 있는 수심측량은 측량선을 타고 사람이 직접 측량하거나 측량선을 이용하여 목표지점을 측정하는 방법 등이 주로 이용된다. 그러나 현재 이용되는 측량선은 유인과 무인시스템으로 나누어져 있어 수심의 상태 또는 기상상태에 따라 능동적인 대처가 어려웠다. 따라서 본 연구에서는 악천후나 광활한 지역과 같이 접근성이 어려운 곳은 무인 원격제어를 이용하여 수심 측정이 가능한 측량선을 구현하고자 한다. 본 연구에서 개발된 유 무인 측량선의 제어시스템은 무선통신을 이용하여 사용자에 의해 미리 설정한 경로대로 움직이는 자동제어방식과 제어국에서 직접 측량선의 방향과 속도 등을 제어 할 수 있는 최적화 된 수동제어방식의 측량이 가능하게 하였다.

• 한국동물학회지
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• 제11권3호
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• pp.85-91
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• 1968

1963年에서 1967年에 걸쳐 서울地區의 人工放射能과 自然放射能을 全放射能의 測定과 放射性核種의 分析을 통하여 硏究하였다. 核分裂生成物의 濃度가 적을때는 \ulcorner은 半減期를 갖는 라듐이나 토리음의 崩壞生成物이 浮游塵의 大部分을 차지하고 있었으며 核分裂生成物에 依한 放射能은 試料 採取후 며칠 지나야 正確히 評價할수 있었다. 7次에 걸친 中共의 核實驗의 結果 두차례의 强放射能이 爆發후 30時間을 前後하여 서울地區에 나타났으며 이들은 1956年에서 1962年 사이에 美國과 蘇聯에서 행한 實驗과 比較할 때 높은 比放射能을 보였으나 持續時間은 아주 짧아서 1週內에 急激히 減少하였다. 이로 보아서 서울地區의 放射能汚染은 中共의 核實驗인 境遇 核實驗의 規模와 實驗高度 및 爆發前後의 氣象條件, 特히 高層對流圈의 제트氣流에 依해서 많은 影響을 받음을 알았다.

• 대한의료기공학회지
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• 제7권2호
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• pp.134-145
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• 2004

Qi. in ancient east Asian Philosophy and medicine, was the quintessential concept symbolizing material orgin of the world. It was considered as the original matter of the world, and the genesis, development and extinction of everything in heaven and earth was explained through the movement of Qi. Despite its importance, the interpretation of Qi has brought about various bifurcations in the history of Oriental medicine. It is comprehended either as ideal concept, or as actual entity. Also, there exists synthetic idea of considering both sides of Qi. These ideas results from obscure understanding based on textual interpretation apart from actual experince. When experincing Qi through discipline, however, man can understand Qi concretly and actually and even grasp the explanation of the cosmos and life. One problem of Qi discipline was that it couldn't ascend the stage of subjective experience. Now, with the method of 'Hanalmomjit'. a developed form of zifadonggong(自發動功), I could reach coherent results to offer the foundation of objective understanding of Qi. The testees, disciples of Hanalmomjit, could express the characters of herbs in their Qigong actions, and the expression was meaningful and coherent to be considered as expressing the effects described in the classics of herbalogy. This result comes from the capacity of grasping external Qi-status, not only expressing the internal communication of jingluo(經絡) in Hanalmomjit.

• 한국지반공학회논문집
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• 제19권6호
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• pp.161-168
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• 2003

대부분의 자연상태의 사질토는 어느 정도 경화되어 있다. 경화의 정도는 흙의 체적변형 거동이나 강도에 중요한 영향을 준다. 경화된 사질토 지반의 중요한 특징은 사질토임에도 불구하고 굉장히 높이 서 있을 수 있다는 것이다. 많은 현장 관측이나 경화모래로 된 사면의 파괴 해석들은 기존의 사면해석방법이 적절하지 않다는 것을 보여준다. 이것은 단지 파괴면이 원호가 아니라는 점뿐만 아니라 파괴면에서의 전단응력이 실험으로부터 얻어진 전단강도보다 훨씬 작기 때문일 것이다. 이러한 사실은 파괴양상이 Mohr-Coulomb 전단파괴와 다르다는 것을 말한다. 이런 파괴는 파괴역학 개념과 이론으로 설명될지도 모른다. 이 논문에서는 파괴 역학 개념을 이용해서 경화모래로 이루어진 급경사 사면의 해석을 수행하였다. FEM 해석 결과는 파괴역학의 개념을 이용한 해석방법이 경화사질토로 이루어진 지반구조물의 설계나 안정해석에 훌륭한 대안임을 보여주고 있다.