• Korean journal of communication and information
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• v.36
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• pp.135-161
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• 2006

The aim of this study is to examine who had participated as members of the editorial staffs and their role in the Independent. In spite of the historical significance of the Independent, this topic was not treated properly by related studies. Moreover many studies mainly based on the Philip Jaisohn's autobiography showed the tendency to overemphasize his role. This study tried to overcome the limitations of the existing studies by critical reinterpretation of the historical materials and some new documents. The result of this study shows that 9 persons participated in the Independent. They are Philip Jaisohn, Joo Si-kyung, Yoon Chi-ho, Homer B. Hulbert, Son Seung-yong, Lee Jun-il, Henry Gerhart Appenzeller, H. Emberley and George Cobb. Five person including Jaisohn were Koreans and the rest were foreigners. Hulbert took part in editing English edition confidentially during some month from the beginning. Son Seung-yong seems to be the only one man to participate from beginning to end. Lee Jun-il was not a editorial staff but a treasurer, and Cobb participated temporarily in proofreading. Hulbert and Cobb were not official staff.

• Aerospace Engineering and Technology
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• v.12 no.1
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• pp.40-45
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• 2013

Satellite's infrared detector shall be calibrated under thermal vacuum environment using a reference black body before a launch. The full aperture black body (FABB) as an infrared calibration reference shall be composed of vacuum compatible materials and temperature controlled from $-40^{\circ}C$ to $+40^{\circ}C$ with emissivity higher than 0.95. The temperature homogeneity over the central 80 % area of the FABB front surface shall be better than 2 K. The FABB designed by thermal and flow analysis was $1m{\times}1m{\times}8mm$ copper plate on which black painted aluminum honeycomb core was attached. Copper tubes were welded on the opposite side of the honeycomb core to allow temperature regulated gaseous nitrogen to flow through them. By the FABB validation test, the temperature homogeneity was observed around 1 K using 20 PT100 sensors and modified COTS infrared camera. The emissivity value was 0.975 at $40^{\circ}C$ under atmospheric pressure.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1754-1759
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• 2008

To produce plastic parts that have fine pattern through conventional injection molding, a lot of difficulties follow. Therefore, rapid heating and cooling methods are good candidates for manufacturing injection-molded parts with micro/nano patterns. In this study, we adopted the E-Mold patent technology. The mold for E-Mold technology has a separate heated core with micro heaters. It is very important to optimize the lay-out of the heaters in heated core because it influences both control and distribution of mold temperature. We developed a optimization method of heating line lay-out by using commercial softwares and compared the output with the experimental results. We used Pro-Engineer Wildfire 2.0 for the mold design, ICEMCFD for mesh generation, and FLUENT for heat transfer simulation. The simulation results showed the temperature profile from $60^{\circ}C$ to $120^{\circ}C$ or $180^{\circ}C$ during heating and cooling process which were compared with the injection molding experiments. We concluded that the simulation could well explain the experimental results. It was shown that the E-Mold optimization design for heater lay-out could be available through the simulation.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.23-28
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• 2002

본 연구에서는 간단한 조작을 통하여 작물의 특성에 따라 진동방향을 조절 가능하게 함으로써 물리적 성질이 서로 다른 감자, 고구마, 마늘, 양파, 생강 등 거의 모든 뿌리작물의 수확에 이용할 수 있는 다목적 굴취기를 기구학적으로 설계하고, 뿌리작물 굴취기의 성능에 영향을 미치는 진폭, 진동수, 작업속도를 변화시킬 때 각각의 조합에 있어서 굴취판상의 특정한 점들의 운동궤적을 분석하고 이에 기초하여 굴취기의 설계변수와 작업에서의 설정변수 를 결정하고자 하였으며, 그 결과를 요약하면 다음과 같다. 1) 작업위치에 따라 굴취판 뒷부분(선별부)의 진동방향 조절이 가능하기 때문에 진동방향을 조절하면 물리적 성질이 서로 다른 감자, 고구마 마늘, 양파 등 거의 모든 뿌리작물의 수확에 이용할 수 있을 것으로 사료된다. 2) 굴취판의 궤적분석결과 진폭이 3mm일 때에는 캠 축의 회전속도와 작업속도에 관계없이 굴취작업이 불가능할 것으로 판단되었다. 진폭이 6mm일 때에는 작업속도 1.08km/hr에서 캠 축의 회전속도가 841rpm 이상이면 굴취작업이 가능할 것으로 판단되었고, 작업속도 2.16km/hr이상에는 굴취작업이 불가능할 것으로 판단되었다. 진폭이 9mm일 때에는 작업속도 1.08km/hr에서 작업할 때 사용한 캠축의 회전속도에 관계없이 굴취작업이 모두 잘 이루질 것으로 판단되었고, 작업속도 2.16km/hr에서는 캠축의 회전속도가 995rpm 일 경우에만 굴취작업이 가능할 것으로 판단되었으며, 작업속도 3.24km/hr에서는 작업위치나 캠축의 회전속도에 관계없이 모두 굴취작업이 불가능한 것으로 사료된다. 3) 작업속도를 1.08km/hr 이상으로 하려면 소요동력의 관점에서 볼 때 진폭은 크게하고 진동수는 작게 하는 것이 유리하기 때문에 진폭을 9mm이상 취하는 것이 바람직할 것으로 사료된다.회로 가장 많이 발생하였으며, 다음으로 밀양과 나주지역이 29회, 김제지역이 28회 등으로 많은 발생빈도를 보였다.생시 진화방법의 개발 등에 대한 기본data로서의 역할을 충분히 할 수 있을 것으로 사료된다. 평가되었다.us에 대하여 높은 것으로 나타났다.bangular에서 subrounded에 해당한다. 이러한 현저한 차이를 보이는 이유는 남극적 빙하성 환경 조건과 이 지역의 해양 퇴적학적 특성에 그 원인이 있다고 해석된다.ea. Our ancestors really began to drink teas from the period of Unified Sila on. This country turning to the Koryo dynasty, tea drinking manner began to prevail so much that drinking tea became a ceremony. Daring the Yi dynasty it was much camplicated to make and boil the leaf tea. As a result of the previous fact pure tea came to have disappeared and odorous pharmaceutical became prevailent. 7) For value of exploiting Kungjuk tea (ginger tea seasoned with phyllostachy and addition of honeyl) was the highest among many. The worth of developing all the teas among all the beverages was regarded as that high of 51%, while even the tea regarded as worthless obtai

• International Journal of Highway Engineering
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• v.18 no.2
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• pp.73-82
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• 2016

PURPOSES: The national highways and expressways in Korea constitute a total length of 17,951 km. Of this total length of pavement, the asphalt pavement has significantly deteriorated, having been in service for over 10 years. Currently, hot in-place recycling (HIR) is used as the rehabilitation method for the distressed asphalt pavement. The deteriorated pavement becomes over-heated, however, owing to uncontrolled heating capacity during the pre-heating process of HIR in the field. METHODS: In order to determine the appropriate heating method and capacity of the pre-heater at the HIR process, the heating temperature of asphalt pavement is numerically simulated with the finite element software ABAQUS. Furthermore, the heating transfer effects are simulated in order to determine the inner temperature as a function of the heating system (IR and wire). This temperature is ascertained at $300^{\circ}C$, $400^{\circ}C$, $500^{\circ}C$, $600^{\circ}C$, $700^{\circ}C$, and $800^{\circ}C$ from a slab asphalt specimen prepared in the laboratory. The inner temperature of this specimen is measured at the surface and five different depths (1 cm, 2 cm, 3 cm, 4 cm, and 5 cm) by using a data logger. RESULTS: The numerical simulation results of the asphalt pavement heating temperature indicate that this temperature is extremely sensitive to increases in the heating temperature. Moreover, after 10 min of heating, the pavement temperature is 36%~38% and 8%~10% of the target temperature at depths of 25 mm and 50 mm, respectively, from the surface. Therefore, in order to achieve the target temperature at a depth of 50 mm in the slab asphalt specimen, greater heating is required of the IR system compared to that of the gas. CONCLUSIONS : Numerical simulation, via the finite element method, can be readily used to analyze the appropriate heating method and theoretical basis of the HIR method. The IR system would provide the best heating method and capacity of HIR heating processes in the field.

• The Journal of the Convergence on Culture Technology
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• v.5 no.3
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• pp.345-349
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• 2019

In Korea, the mountainous area occupies more than 70% of the whole country, cutting of earth slope that cuts a part of the ground surface is widely used when building infrastructures such as road, railroad, and industrial complex construction. In recent years, regulations on environmental damage have become more strict, and various methods have been developed and applied. Among them, Concrete-Panel Retaining Wall technique is actively applied. Concrete-Panel Retaining Wall is a method to resist horizontal earth pressure by forming a wall by attaching a precast retaining wall to the front of the support material and increasing the shear strength of the disk through reinforcement of the support material. Soil nailing, earth bolt, and ground anchor are used as support material. Among them, ground anchor is a more aggressive reinforcement type that introduces tensile load in advance to the steel wire, and a large concentrated load acts on the front panel. This concentrated load is a factor that creates cracks in the concrete panel and reduces the durability of the retaining wall itself. In this study, steel pipe sleeves and reinforcements were purchased at the anchorage of the panel to prevent cracks, and by applying bumpy shear keys to the end of the panel, the weakness of the individual behavior of the existing grout anchors was improved. The problem of degraded landscape by exposure to front concrete of retaining wall and protrusion of anchorage was solved by the production of natural stone patterns and the construction of sections that do not protrude the anchorage. In order to verify the effectiveness of anti-crack sleeves and reinforcements used in the null, indoor testing and three-dimensional numerical analysis have been performed, and the use of steel pipe sleeves and reinforcements has demonstrated the overall strength increase and crack suppression effect of panels.

• Economic and Environmental Geology
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• v.54 no.1
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• pp.117-126
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• 2021

Satellite magnetic observations reflect the magnetic properties of deep crust about the depth of Curie isotherm that is a boundary where the magnetic nature of the rocks is disappeared, showing long wavelength anomalies that are not easily detected in near-surface data from airborne and shipborne surveys. For this reason, they are important not only in the analyses on such as plate reconstruction of tectonic boundaries and deep crustal structures, but in the studies of geothermal distribution in Antarctic and Greenland crust, related to global warming issue. It is a conventional method to compute the spherical harmonic coefficients from global coverage of satellite magnetic observations but it should be noted that inclusion of erroneous data from the equator and the poles where magnetic observations are highly disturbed might mislead the global model of the coefficients. Otherwise, the reduced anomaly model can be obtained with less corruption by choosing the area of interest with proper data processing to the area. In this study, I produced a satellite crustal magnetic anomaly map over East Asia (20° ~ 55°N, 108° ~ 150°E) centered on Korean Peninsula, from CHAMP satellite magnetic measurements about mean altitude of 280 km during the last year of the mission, and compared with the one from global crustal magnetic model (MF7). Also, a comparison was made with long wavelength anomalies from EMAG2 model compiled from all near-surface data over the globe.

• 한국노년학
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• v.28 no.4
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• pp.1113-1128
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• 2008

Purpose: The aim of the present study was to investigate toilet terms and pictograms recognized by elders living in Seoul and Incheon. Method: Data were collected from 308 elders by individual interviews using questionnaires. Result: As for the name of places for elimination, those elders responded Hwajangsil 88.3%, followed by Byeonso 49.3% and Dwitgan 44.4%. Most elders preferred Hwajangsil as the term indicating the place for elimination. The mean age of the group preferred Bunso was significantly higher than that of the group preferred Hwajangsil, whereas educational level was higher in the latter group. Of the 256 respondents, 55% preferred the pictogram of international toilet sign, while 34.8% preferred the pictogram of toilet stool. Those with no formal education tended to prefer the pictogram of toilet stool. Conclusion: The term Hwajangsil is suggested for indicating toilet for elders in general. Other terms familiar with residents need to be investigated in the facilities for elders and those terms should be used in combination with Hwajangsil. English toilet signs alone are not recommended for elders. Simple pictograms of toilet stool is suggested for elders with low educational level. Toilet signs for elders need to include both terms and pictograms.

• Journal of the Korean earth science society
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• v.43 no.3
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• pp.405-429
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• 2022

Detrital zircon LA-MC-ICP-MS U-Pb dating of the Cretaceous Gurye Group, Gurye Basin, was carried out. Gurye Group consists of Supyeongri, Geumjeongri, Togeum, and Obongsan formations in ascending order, and five samples were collected for age dating. Based on the dating results, the lowermost Supyeongri and the uppermost Obongsan formations show narrow age ranges. Only Precambrian and Late Cretaceous zircons were found in the Supyeongri and Obongsan formations, respectively. However, the upper and lower Geumjeongri, and Togeum formations show wide age ranges from the Precambrian to Cretaceous. The youngest detrital zircon U-Pb ages of each formation except the Supyeongri Formation, which lacks Cretaceous zircon, were calculated to be ca. 107.4 Ma in the lower Geumjeongri Formation, ca. 104.6 Ma in the upper Geumjeongri Formation, ca. 97.7 Ma in the Togeum Formation, and ca. 88.5 Ma in the Obongsan Formation. Such results indicate that the depositional age of the Gurye Group can be constrained from the Lower Cretaceous Albian to the Upper Cretaceous Coniacian. Based on the distribution of the detrital zircon ages from each formation, the source area of the Gurye Group is interpreted to have been extended from the adjacent Youngnam Massif to the Okcheon Belt throughout the basin evolution. The increase of the Cretaceous zircon with time is thought to reflect the slab roll-back of the proto-Pacific plate during the Cretaceous.

• Journal of the Korean Geotechnical Society
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• v.23 no.1
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• pp.23-37
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• 2007

Recently a concept of pile-tip enlarged PHC pile (Ext-PHC pile), for use in the auger-drilled construction method, has been developed and is being implemented in practice. A series of field axial load tests on both PHC and Ext-PHC piles were conducted at an experimental site. In addition, a parametric study on a number of influencing factors was made using a validated finite element model. The field axial load tests indicated an enhanced load-settlement characteristics for the Ext-PHC piles compared with the PHC piles, giving approximately 50% increase in the end bearing capacity. Also found in the results of the parametric study was that the increase in the end bearing capacity of Ext-PHC piles slightly varies with the mechanical properties of supporting ground as well as pile length, in the range of 1.25 to 1.4 time that of PHC. Overall, the results of the field tests as well as the numerical study confirmed that the end bearing capacity of PHC pile can be improved by the concept of.Ext-PHC pile.