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Korean Medical Doctor Shin Hong-Gyun's Life and His Independence Movement (신홍균(신홍균(申洪均): 개명(改名) 신흘(申屹), 신굴(申矻)) 한의사의 생애와 독립운동)

  • Jung Sang Gyu;Shin Min Shik
    • The Journal of Korean Medical History
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    • v.34 no.1
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    • pp.31-46
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    • 2021
  • Shin Hong-Gyun and his family have been in medicine for many generations as Korean Medical Doctors (KMDs). In 1919 when Shin Hong-Gyun was participating in an independence movement in Jang-Baek-Hyun, his younger brother Shin Dong-Gyun was killed by Japanese military police forces. This tragic incident triggered Shin Hong-Gyun to establish an army for national independence called , holding 200 young men, to serve in armed struggle against the Japanese Government with Kim Jung-Geon in May, 1920. In March 1933, Shin Hong-Gyun, as a military surgeon, led his men to the Korean Independence Army to fight a battle. Once he became a member of the Korean Independence Army, he, in fact, participated in few battles: Sadohaja, Dong-Kyung-Sung, Deajeonjayeong. Daejeonjayeong was a waypoint that the Japanese military needed to pass through in order to reach the Wangcheong area. Shin Hong-Gyun's independence forces had to endure painful starvation and heavy rain while hiding in ambush for long periods of time until the Japanese military would appear. Due to its summer rainy season, rainwater overflowed into their trenches and was filled up to the waist. Even worse, food stockpiles were low and the Japanese army did not appear for longer time. Shin Hong-Gyun's entire team suffered severe hunger and extreme cold. At this critical moment, Shin Hong-Gyun used his expertise as a KMD to find edible black mushrooms that grow wild in the mountains and use them to feed his men. This event led to the victory of the independence army at the battle of Daejeonjayeong. The purpose of the paper is to inform and highlight the forgotten history of Shin Hong-Gyun who was, both, a Korean Medical Doctor and a military surgeon.

Soil Respiration in Pinus rigida and Larix leptolepis Plantations (리기다소나무와 낙엽송(落葉松) 인공조림지내(人工造林地內) 토양발생(土壤發生) 이산화탄소(二酸化炭素)에 관한 연구(硏究))

  • Son, Yowhan;Kim, Hyun-Woo
    • Journal of Korean Society of Forest Science
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    • v.85 no.3
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    • pp.496-505
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    • 1996
  • Soil respiration was measured every two weeks from May through November 1995 using the soda lime method in 40-Year-old Pinus rigida and Larix leptolepis plantations on a similar soil in Yangpyeong, Kyonggi Province. Treatments included control and no-roots(plots trenched and root regrowth into plots prevented). Root respiration was evaluated by comparing no-roots sub-plots to control plots. Mean soil respiration showed highly significant species effects(p<0.01) and was highest at the Pinus rigida control plot($0.38g/m^2/hr$) and lowest at the Larix leptolepis no-roots plot($0.31g/m^2/hr$). High soil respiration in Pinus rigida may be related to aboveground litter production. The annual $CO_2$ fluxes ranged from 23 to 27t/ha/yr. We found significant correlations between temperatures(air : $R^2$=0.53, soil : $R^2$=0.55) and soil respiration(p<0.01), but no significant correlations between soil moisture and soil respiration(p>0.1). Root respiration was 3% of total soil respiration. We might underestimate rapt respiration because of shallow trenches and $CO_2$measurements right after trenching. Factors controlling soil respiration including belowground litterfall(especially fine roots) inputs, litter quality should be well understood to predict soil carbon fluxes and relative contributions to total soil respiration in forest ecosystems.

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The Water Circulation Improvement of Apartment Complex by applying LID Technologies - Focused on the Application of Infiltration Facilities - (LID 기술 적용을 통한 공동주택단지 물순환 개선 연구 - 침투시설 적용을 중심으로 -)

  • Suh, Joo-Hwan;Lee, In-Kyu
    • Journal of the Korean Institute of Landscape Architecture
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    • v.41 no.5
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    • pp.68-77
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    • 2013
  • Change in the Global Climate causes flood, drought, heavy snow, and rainfall patterns in the Korean Peninsula. A variety of alternatives related to climate change are considered. The foreign researchers are interested in Low Impact Development(LID); the utilization of water resources and eco friendly development, over 10 years ago. The research and development of related technology has been advanced to apply LID techniques in order to develop several projects in the country. However, sharing of technology or system that can be used easily in the private sector is insufficient. The performance of the elements of LID Technology has not been fully agreed. LID elements of this technology are easy to apply to Apartment complex. The elements are classified technology. The infiltration of elements performs the functions of apartment complex landscaping space technology applied to the target. The water cycle simulation(SWMM 5.0) and technology the implementation of the effectiveness is also verified. For this purpose, three different places in apartment complex to target by SWMM5.0 U.S. EPA conducted utilizing simulated rainfall and applying LID techniques before and after the simulated water cycle (infiltration, surface evaporation, and surface runoff) were conducted. The importance of green space in the LID techniques of quantitative and qualitative storm water control as well as the role of Apartment Housing is to promote Amenity. Remember that the physical limitations of apartment complex and smooth water circulation system for the application of LID integrated management techniques should be applied. To this end, landscapes, architecture, civil engineering, environmental experts for technical consilience between the Low Impact Development efforts are required.

A Study on the Dominant Driving Force of Plate Movement presented in the High School Earth Science Textbooks (고등학교 지구과학 교과서에 제시된 판 이동의 주된 원동력에 대한 고찰)

  • Jeon, Taehwan;Seo, Ki-Weon;Lee, Gyuho
    • Journal of the Korean earth science society
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    • v.37 no.1
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    • pp.62-77
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    • 2016
  • In the early model of plate tectonics, the plate was depicted as a passive raft floating on the convecting mantle and carried away by the mantle flow. At the same time, ridge push at spreading boundaries and drag force exerted by the mantle on the base of lithosphere were described as the dominant driving forces of plate movements. However, in recent studies of plate tectonics, it is generally accepted that the primary force driving plate motion is slab pull beneath subduction zones rather than other forces driven by mantle convection. The current view asserts that the density contrast between dense oceanic lithosphere and underlying asthenosphere is the substance of slab pull. The greater density of oceanic slab allows it to sink deeper into mantle at trenches by gravitational pull, which provides a dominant driving force for plate motion. Based on this plate tectonics development, this study investigated the contents of plate tectonics in high school Earth Science textbooks and how they have been depicted for the last few decades. Results showed that the early explanation of plate movement driven by mantle convection has been consistently highlighted in almost all high school textbooks since the 5th curriculum, whereas most introductory college textbooks rectified the early theory of plate movement and introduced a newly accepted theory in revised edition. Therefore, we suggest that the latest theory of plate tectonics be included in high school textbooks so that students get updated with recent understanding of it in a timely manner.

Ordered Macropores Prepared in p-Type Silicon (P-형 실리콘에 형성된 정렬된 매크로 공극)

  • Kim, Jae-Hyun;Kim, Gang-Phil;Ryu, Hong-Keun;Suh, Hong-Suk;Lee, Jung-Ho
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.241-241
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    • 2008
  • Macrofore formation in silicon and other semiconductors using electrochemical etching processes has been, in the last years, a subject of great attention of both theory and practice. Its first reason of concern is new areas of macropore silicone applications arising from microelectromechanical systems processing (MEMS), membrane techniques, solar cells, sensors, photonic crystals, and new technologies like a silicon-on-nothing (SON) technology. Its formation mechanism with a rich variety of controllable microstructures and their many potential applications have been studied extensively recently. Porous silicon is formed by anodic etching of crystalline silicon in hydrofluoric acid. During the etching process holes are required to enable the dissolution of the silicon anode. For p-type silicon, holes are the majority charge carriers, therefore porous silicon can be formed under the action of a positive bias on the silicon anode. For n-type silicon, holes to dissolve silicon is supplied by illuminating n-type silicon with above-band-gap light which allows sufficient generation of holes. To make a desired three-dimensional nano- or micro-structures, pre-structuring the masked surface in KOH solution to form a periodic array of etch pits before electrochemical etching. Due to enhanced electric field, the holes are efficiently collected at the pore tips for etching. The depletion of holes in the space charge region prevents silicon dissolution at the sidewalls, enabling anisotropic etching for the trenches. This is correct theoretical explanation for n-type Si etching. However, there are a few experimental repors in p-type silicon, while a number of theoretical models have been worked out to explain experimental dependence observed. To perform ordered macrofore formaion for p-type silicon, various kinds of mask patterns to make initial KOH etch pits were used. In order to understand the roles played by the kinds of etching solution in the formation of pillar arrays, we have undertaken a systematic study of the solvent effects in mixtures of HF, N-dimethylformamide (DMF), iso-propanol, and mixtures of HF with water on the macrofore structure formation on monocrystalline p-type silicon with a resistivity varying between 10 ~ 0.01 $\Omega$ cm. The etching solution including the iso-propanol produced a best three dimensional pillar structures. The experimental results are discussed on the base of Lehmann's comprehensive model based on SCR width.

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Textural Characters of the Sediments from Neolithic site Moonamni Coastal Zone, East Sea of Korea -Implication of the Holocene High Stand Sea Level (강원도 동해안 문암리 신석기 유적지 퇴적층의 조직 특성)

  • 박용안;김수정;최진용
    • The Korean Journal of Quaternary Research
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    • v.17 no.1
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    • pp.27-37
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    • 2003
  • The Neolithic relics containing sedimentary deposits have been found in the Moonamni coastal zone of the East Sea, Korea. The purpose of this research is to establish the late Quaternary stratigraphy of the coastal dune deposit and to elucidate its depositional environment of the Neolithic-site sediments on the basis of analytical properties of grain size population and mineralogy of the sediments. As a result, the vertical sections of the sediments from three trenches are characterized by three major stratigraphic depositional units of Unit 3, Unit 2 and Unit 1 in ascending order. Unit 3 and 2 can be further divided into tow sub-units. Unit 3 is composed of massive sands in the lower part and muddy sand in the upper part. It is considered that the Unit 3 is a typical dune deposit showing well-sorted sands. Unit 2 is characterized by the cross-bedding, and include archaeological remains such as pottery shards. This unit can be further divided into two sub-units of muddy sand in the lower part and sand in the upper part. Unit 1 occupies the top section and consists of modem dune sediment. The Neolithic cultural remains would be accumulated in the coastal dune area in relation to dynamic condition of beach system under the high stand of Holocene sea-level at about 7,800∼6,500 yr B.P. or so.

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Formation of a MnSixOy barrier with Cu-Mn alloy film deposited using PEALD

  • Moon, Dae-Yong;Hwang, Chang-Mook;Park, Jong-Wan
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.229-229
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    • 2010
  • With the scaling down of ultra large integrated circuits (ULSI) to the sub-50 nm technology node, the need for an ultra-thin, continuous and conformal diffusion barrier and Cu seed layer is increasing. However, diffusion barrier and Cu seed layer formation with a physical vapor deposition (PVD) method has become difficult as the technology node is reduced to 30 nm and beyond. Recent work on self-forming barrier processes using PVD Cu alloys have attracted great attention due to the capability of conformal ultra-thin barrier formation using a simple technique. However, as in the case of the conventional barrier and Cu seed layer, PVD of the Cu alloy seed layer will eventually encounter the difficulty in conformal deposition in narrow line trenches and via holes. Atomic layer deposition (ALD) has been known for its good step coverage and precise thickness control, and is a candidate technique for the formation of a thin conformal barrier layer and Cu seed layer. Conformal Cu-Mn seed layers were deposited by plasma enhanced atomic layer deposition (PEALD) at low temperature ($120^{\circ}C$), and the Mn content in the Cu-Mn alloys were controlled form 0 to approximately 10 atomic percent with various Mn precursor feeding times. Resistivity of the Cu-Mn alloy films decreased by annealing due to out-diffusion of Mn atoms. Out-diffused Mn atoms were segregated to the surface of the film and interface between a Cu-Mn alloy and $SiO_2$, resulting in self-formed $MnO_x$ and $MnSi_xO_y$, respectively. No inter-diffusion was observed between Cu and $SiO_2$ after annealing at $500^{\circ}C$ for 12 h, indicating an excellent diffusion barrier property of the $MnSi_xO_y$. The adhesion between Cu and $SiO_2$ was enhanced by the formation of $MnSi_xO_y$. Continuous and conductive Cu-Mn seed layers were deposited with PEALD into 32 nm $SiO_2$ trench, enabling a low temperature process, and the trench was perfectly filled using electrochemical plating (ECD) under conventional conditions. Thus, it is the resultant self-forming barrier process with PEALD Cu-Mn alloy film as a seed layer for plating Cu that has further potential to meet the requirement of the smaller than 30 nm node.

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Hydrologically Route-based Green Infra facilities assessment Model: Focus on Bio-retention cells, Infiltration trenches, Porous Pavement System, and Vegetative Swales (수문학적 추적 기반의 GI 시설 평가 모델: 생태저류지, 침투도랑, 투수성포장, 식생수로를 대상으로)

  • Won, Jeongeun;Seo, Jiyu;Choi, Jeonghyeon;Kim, Sangdan
    • Journal of Wetlands Research
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    • v.23 no.1
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    • pp.74-84
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    • 2021
  • Active stormwater management is essential to minimize the impact of urban development and improve the hydrological cycle system. In recent years, the Low Impact Development (LID) technique for urban stormwater management is attracting attention as a reasonable alternative. The Storm Water Management Model (SWMM) is actively used in urban hydrological cycle improvement projects as it provides simulation functions for various GI (Green Infra) facilities through its LID module. However, in order to simulate GI facilities using SWMM, there are many difficulties in setting up complex watersheds and deploying GI facilities. In this study, a model that can evaluate the performance of GI facilities is proposed while implementing the core hydrological process of GI facilities. Since the proposed model operates based on hydrological routing, it can not only reflect the infiltration, storage, and evapotranspiration of GI facilities, but also quantitatively evaluate the effect of improving urban hydrological cycle by GI facilities. The applicability of the proposed model was verified by comparing the results of the proposed model with the results of SWMM. In addition, a discussion of errors occurring in the SWMM's permeable pavement system simulation is included.

The Impact of COVID-19 on the Labor Market in India: Focusing on the Expansion of the Labor Gap and Digitization (COVID-19가 인도 노동시장에 미친 영향: 노동격차 확대와 디지털화를 중심으로)

  • Kang, Sung Yong;Lee, Myung Moo;Kim, Yun Ho;Nam, Eun Young;Lee, Sang Keon
    • Journal of Appropriate Technology
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    • v.7 no.1
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    • pp.102-114
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    • 2021
  • India has recently experienced an acute crisis confronting the COVID-19 pandemic as confirmed cases exceeded 11.73 million in March 2021, which was the second worst scale only after the United States. The strict lockdown measures as well as the pandemic itself posed a serious threat of survival, in particular, to immigrant workers engaged in informal sectors, which triggered their reverse immigration. In case the COVID-19 pandemic continues in 2021, it is estimated that in the sector of tourism and service alone, more than 20 million jobs will disappear. The damage on industry is already being realized with the significant decrease of workforce. It is important to note, however, that jobless growth and labor polarization were observed even before the outbreak of COVID-19, and that the pandemic only served as one of the trigger catalysts that made those submerged problems burst out. In this study, we examine the structural problems in industry and labor market in India and consider the social context and efficacy of the "Make in India" or "Atmanirbhar Bhrat" policy. The latter initiative was presented in the trenches of the pandemic in 2020. While considering the complexity of problems, we would like to pursue a future-oriented approach and propose a direction in restructuring the labor market, attempted at reversing the critical conditions following the fourth industrial revolution and digitization into the shortcut to labor market restructuring.

A Study on the Comparison of the Backfill Loads Obtained by the Marston-Spangler에s Theory and by the Finite Element Analysis for the Metal-Polyethylene Composite Pipes (금속-폴리에틸렌 복합관에 대해서 Marston-Spagler이론과 유한요소해석에 의해 구해진 뒤채움하중의 비교에 관한 연구)

  • 정진호
    • Geotechnical Engineering
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    • v.14 no.5
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    • pp.89-110
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    • 1998
  • Variations of backfill load on the metal-polyethylene composite( MPC ) pipes buried in various trenches backfill afterward were investigated in this paper. The backfill loads obtained by the finite element method( FBM ) were compared with those calculated by the well-known MarstonBpangler(M-5) theory. The reliability of the finite element analysis used in this study was examined by an inaitu best for the buried pipe. The backfill lords and deflections on the real-size pipe buried on-site were measured while increasing the backfill height. In addition, further investigations were made for the variations of the backfill loads as a function of several important parameters such as the backfill soil type, bach. height$(\leq4.0m)$, diameter of the pipe$(B.$1.0m)$, and trench width($\leq 3.0 B_c$). It is confirmed that the M-S theory predicts reasonably well the backfill loafs of the MPC of the M-S backfill coils be 0.13 and 0.15 for the SC and SM coils in the D unman soil model, respectively. The load ratio, Wu-s/WwgM for a narrow trench varies negligibly with the back(111 height but fiends to increase for a wide trench. The ratio increases with increasing diameter of the pipe for a narrow trench while decreasing for a wide trench. It is also found that the ratio generally decreases as the degree of compaction increases and BM soil exhibits larger load ratio than that of SC soil.

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