• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.6
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• pp.635-642
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• 2014

In this paper, an efficient technique is developed to predict failure probability of three failure modes(case rupture, fracture and bolt breakage) related to solid rocket motor case due to the inner pressure during the mission flight. The overall procedure consists of the steps: 1) design parameters affecting the case failure are identified and their uncertainties are modelled by probability distribution, 2) combustion analysis in the interior of the case is carried out to obtain maximum expected operating pressure(MEOP), 3) stress and other structural performances are evaluated by finite element analysis(FEA), and 4) failure probabilities are calculated for the above mentioned failure modes. Axi-symmetric assumption for FEA is employed for simplification while contact between bolted joint is accounted for. Efficient procedure is developed to evaluate failure probability which consists of finding first an Most Probable Failure Point(MPP) using First-Order Reliability Method(FORM), next making a response surface model around the MPP using Latin Hypercube Sampling(LHS), and finally calculating failure probability by employing Importance Sampling.

• Journal of Cadastre & Land InformatiX
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• v.51 no.2
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• pp.73-82
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• 2021

According to the government's announcement of the safety management enhancement policy for small and medium-sized private construction sites, the subject of mandatory CCTV installation has been expanded from large construction sites to small and medium-sized construction sites. However, since the existing CCTV at construction sites has been used for simple control for safety management, so research is needed for monitoring of construction sites. Therefore, in this study, three vanishing points were calculated based on a single image taken with a monocular camera, and then a camera matrix containing interior orientation parameters information was determined. And the accuracy was verified by calculating the height of the target object from the height of the reference object. Through height determination experiments using vanishing points based on a monocular camera, it was possible to determine the height of target objects only with a single image without separately surveying of ground control points. As a result of the accuracy evaluation, the root mean square error was ±0.161m. Therefore, it is determined that the progress of construction work at the construction sites can be monitored through the single image taken using the single camera.

• The Korean Journal of Petroleum Geology
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• v.14 no.1
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• pp.1-11
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• 2008

As conventional oil and gas reservoirs become depleted, interests for oil sands has rapidly increased in the last decade. Oil sands are mixture of bitumen, water, and host sediments of sand and clay. Most oil sand is unconsolidated sand that is held together by bitumen. Bitumen has hydrocarbon in situ viscosity of >10,000 centipoises (cP) at reservoir condition and has API gravity between $8-14^{\circ}$. The largest oil sand deposits are in Alberta and Saskatchewan, Canada. The reverves are approximated at 1.7 trillion barrels of initial oil-in-place and 173 billion barrels of remaining established reserves. Alberta has a number of oil sands deposits which are grouped into three oil sand development areas - the Athabasca, Cold Lake, and Peace River, with the largest current bitumen production from Athabasca. Principal oil sands deposits consist of the McMurray Fm and Wabiskaw Mbr in Athabasca area, the Gething and Bluesky formations in Peace River area, and relatively thin multi-reservoir deposits of McMurray, Clearwater, and Grand Rapid formations in Cold Lake area. The reservoir sediments were deposited in the foreland basin (Western Canada Sedimentary Basin) formed by collision between the Pacific and North America plates and the subsequent thrusting movements in the Mesozoic. The deposits are underlain by basement rocks of Paleozoic carbonates with highly variable topography. The oil sands deposits were formed during the Early Cretaceous transgression which occurred along the Cretaceous Interior Seaway in North America. The oil-sands-hosting McMurray and Wabiskaw deposits in the Athabasca area consist of the lower fluvial and the upper estuarine-offshore sediments, reflecting the broad and overall transgression. The deposits are characterized by facies heterogeneity of channelized reservoir sands and non-reservoir muds. Main reservoir bodies of the McMurray Formation are fluvial and estuarine channel-point bar complexes which are interbedded with fine-grained deposits formed in floodplain, tidal flat, and estuarine bay. The Wabiskaw deposits (basal member of the Clearwater Formation) commonly comprise sheet-shaped offshore muds and sands, but occasionally show deep-incision into the McMurray deposits, forming channelized reservoir sand bodies of oil sands. In Canada, bitumen of oil sands deposits is produced by surface mining or in-situ thermal recovery processes. Bitumen sands recovered by surface mining are changed into synthetic crude oil through extraction and upgrading processes. On the other hand, bitumen produced by in-situ thermal recovery is transported to refinery only through bitumen blending process. The in-situ thermal recovery technology is represented by Steam-Assisted Gravity Drainage and Cyclic Steam Stimulation. These technologies are based on steam injection into bitumen sand reservoirs for increase in reservoir in-situ temperature and in bitumen mobility. In oil sands reservoirs, efficiency for steam propagation is controlled mainly by reservoir geology. Accordingly, understanding of geological factors and characteristics of oil sands reservoir deposits is prerequisite for well-designed development planning and effective bitumen production. As significant geological factors and characteristics in oil sands reservoir deposits, this study suggests (1) pay of bitumen sands and connectivity, (2) bitumen content and saturation, (3) geologic structure, (4) distribution of mud baffles and plugs, (5) thickness and lateral continuity of mud interbeds, (6) distribution of water-saturated sands, (7) distribution of gas-saturated sands, (8) direction of lateral accretion of point bar, (9) distribution of diagenetic layers and nodules, and (10) texture and fabric change within reservoir sand body.

• Korean Journal of Heritage: History & Science
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• v.53 no.1
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• pp.52-63
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• 2020

This study was conducted in order to evaluate the characteristics of air temperature fluctuation inside the Daegeumgul, Ondaldonggul, and Seongnyugul Caves, which are the most representative limestone caves in Korea, and also to assess the effects of air temperature on cave temperature. Temperature was measured hourly at three sites in Daegeumgul, Ondaldonggul, and Seongnyugul Caves from April 13 to June 25, 2019. Additionally, air temperature data for the areas around the caves was provided by the Meteorological Administration. Using this collected data, the basic statistical measure of fluctuation characteristics over time was ascertained, and time series analyses were performed. Wide variation of temperature was exhibited in the order of the cave entrance, the cave water inflow point, and the midpoint. Cave temperature was observed to increase gradually during the study period. There was a vast range in temperature at the Daegeumgul station located approximately 150 m outside the cave, but it remained nearly constant beyond the midpoint. Although the effect of air temperature was not significant due to the influence of visitors, the effect of air temperature on cave temperature gradually decreased from the entrance to the interior. At Ondaldonggul, there was a wide range in temperature recorded at the entrance due to the influence of air temperature, but it stayed almost constant in the interior. However, at the site where cave water flows into the cave, temperature was influenced by the cave water temperature. At Seongnyugul, there was a distinct fluctuation in temperature recorded at the cave entrance, while the middle of the cave remained nearly constant. Temperature fluctuated due to the air temperature at the entrance, while at the middle of the cave, measurements were expected to be affected to a greater extent by the lake water temperature than by the air temperature. However, this pattern was not observed. According to the time series analysis results, in all caves, fluctuations of air temperature affected cave temperature after approximately one hour. Cave size and structure, water presence, the entrance's size and shape, air flow, and visitor patterns can all influence cave temperature. Therefore, consideration of these factors is very important in the pursuit to clearly understand cave temperature characteristics.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.1
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• pp.1-9
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• 2007

${\ulcorner}$Hamsansachon Dongyi Suse Bowon Gabogubon${\lrcorner}$ , discovered in 2000, can give very precious information in order to study the formation and development process of ${\ulcorner}$Dongyi Suse Bowon${\lrcorner}$ ${\ulcorner}$The Dircourse on the Constitutional Symptoms and Disease${\lrcorner}$ . I examined, by comparison, changes in understanding pathology explained in ${\ulcorner}$Dongyi Suse Bowon${\lrcorner}$ ${\ulcorner}$The Discourse on the Constitutional Symptoms and Disease${\lrcorner}$ of Gabobon and Sinchukbon, and consequently tried to define the concept of Dispositional Symptom(Dispositional disease) as below, in a point of view that ‘Dispositional Symptom(Dispositional disease)’ should be the key word in explaining the changes in understanding of pathology. Dispositional Symptom(dispositional disease) is a new concept that was first troduced in the Kyongjabon, not found in the Gabobon, and that played a key role in editing ${\ulcorner}$Dongyi Suse Bowon${\lrcorner}$ ${\ulcorner}$The Discourse on the Constitutional Symptom and Disease${\lrcorner}$ . Dispositional Symptom(dispositional disease) means an innate temperament or a pathological tendency, which is already constructed in the system of an individual, prior to expression of specific diseases and symptoms, and can be a primary basis to tell the susceptibility and developing pattern of a certain disease, to decide how to treat and forecast the prognosis. Sinchukbon inductively categorized symptoms of the dispositional symptom (dispositional disease) into the concept of ‘Eight principles’, or eight standards of diagnosis, such as superficies-interior, cold-heat, and weakness-strength.

• Korean journal of applied entomology
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• v.55 no.2
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• pp.109-117
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• 2016

We investigated the control of Bemisia tabaci adults in tomato greenhouses using the eggplant as a trap plant with 4 systemic chemicals. The control effect of dinotefuran SG 50% on tobacco whitefly adults was 80% mortality, the highest than that cyantraniliprole, pyridaben and clothianidin, 51.0%, 12.4% and 11.0% respectively when all chemicals with recommended doses were used. Dinotefuran was applied at various doses and was observed to be most effective above 200ppm (88.4%)t. The control effect of dinotefuran lasted for appromimately nine 9 days and the density of tobacco whitefly adults increased there after. In field tests, the densities of tobacco whitefly adults on tomato shoots were highest at points 0, 15 and 20 m from the eggplant traps and lowest at 5 and 10 m. When the density of tobacco whitefly was low and the eggplants with dinotefuran SG 50% were placed in the tomato greenhouse at 10 m intervals, the overall density of tobacco whitefly adults was lower. In addition, densities were higher at the side of the greenhouse than in the interior and further away from the eggplant. When the density of tobacco whitefly was high and the eggplants with dinotefuran were placed at 5 m intervals, the density of tobacco whitefly at each 5 m point decreased. Theses results confirm that the eggplant is an effective trap plant for attracting tobacco whitefly audlts and combined with dinotefuran SG 50% decreases the density of tobacco whitefly in tomato greenhouses.

• Journal of architectural history
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• v.15 no.1 s.45
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• pp.29-40
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• 2006

This paper is focused on Damheonseo(湛軒書), an anthology written by Hong Daeyong, and I deal with Chinese Architectural views which he had experienced in his itinerary to Beijing, and the vivid pictures of Joseonkwan (called the Koryo or Joseon Embassy) located in Beijing at that time. He was a scholar of great erudition over astronomy, mathematics, military science, politics, and so on. He was interested in practical sciences at early time, and criticized secular scholars full of vanity who had presented purposeless articles. In his age of 35, Qianlong(乾隆) 30 (1764, Youngjo 41), he, a military escort, accompanied by Hong Uk, Joseon envoy and his uncle. Before his itinerary, he self-studied Chinese. Also, during a long journey he got new experiences and information around each area, deviating his group whenever he had some times. He could get more variant experiences than others because of his character full of curiosity, and his observations from the vivid lives of the time helped us get various views between Chinese and Korean architecture. Likewise, although he denounced Qing(淸) scathingly as a barbarian, he mentioned several points about the characteristics of Chinese architecture at that time. First of all, totally Chinese architecture had strong rational and practical points. Secondly, based on bountiful products, buildings along streets shown in Chinese city had sophisticated compositions, and luxurious and magnificent appearances. Thirdly, using the brick from walls to houses was so universal. Fourthly, the layouts of building with three- or four-closed courtyard had very orderly shapes, and the structure of street was also so arranged. Finally, because of stand-up lives, the scales and appearances of interior space were even more extended, and storages were less developed than those of Joseon. As another points, I found that Joseonkwan was moved next to Shushangguan(庶常館)from Huidongnanguan(會同南館) around Hanlimyuan(翰林院), and had been remodeled into a house with Korean custom in using the inner spaces, although it was followed by a closed courtyard style. Likewise, I recognized that Ondols were sure to be established in all temporary houses during the journey to Qing, and felt their strong traditional residential custom in such mentions. Now that the past pictures have disappeared and ways of life and our values have been largely changed, this study has very important meaning in comparing the ancient Chinese and Korean architecture.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.6_1
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• pp.503-509
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• 2013

The KOMPSAT-3 (Korea Multi-Purpose Satellite-3), was launched on May 18, 2012, is an optical high-resolution observation mission of the Korea Aerospace Research Institute and provides RPC(Rational Polynomial Coefficient) for ground coordinate determination. It is however need to adjust because RPC absorbs effects of interior-exterior orientation errors. In this study, to obtain the suitable adjustment parameters of the vendor-provided RPC of the KOMPSAT-3 images, six types of adjustment models were implemented. As results, the errors of two and six adjustment parameters differed approximately 0.1m. We thus propose the two parameters model, the number of control points are required the least, to adjust the KOMPSAT-3 R PC. According to the increasing the number of control points, RPC adjustment was performed. The proposed model with a control point particularly did not exceed a maximum error 3m. As demonstrated in this paper, the two parameters model can be applied in RPC adjustment of KOMPSAT-3 stereo image.

• Journal of Korean Medical classics
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• v.19 no.3
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• pp.184-197
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• 2006

${\ulcorner}$Hwangje-Naegyeong${\lrcorner}$ described Tae Hue(太虛) cosmos which consist of the Great Gi(大氣) produce ${\ulcorner}$Hwangje-Naegyeong${\lrcorner}$ which affected by the theory of activity of Gi(氣化說) in the Han period represent that Tae Hue is spring head of Gi(氣), concurrently said the Time and the Space were established by operating of Gi(氣). As of the Theories of heavenly structure, ${\ulcorner}$Hwangje-Naegyeong${\lrcorner}$ was write in long perod, so it include three branch theory. ${\ulcorner}$Hwangje-Naegyeong${\lrcorner}$ contained the Hypothesis of Covering Heaven(蓋天說), the Hypothesis of Armillary Sphere(渾天說) and the Hypothesis of Chaosheavens(宣夜說) in the Han perod. The Hypothesis of Covering Heaven(蓋天說) means that the sky is round and the ground falls Square(天圓地方). ${\ulcorner}$Hwangje-Naegyeong${\lrcorner}$ involve the Hypothesis of Covering Heaven by the fact that it divide heaven and earth by top and bottom. The Hypothesis of Armillary Sphere(蓋天說) is not directly appeared in ${\ulcorner}$Hwangje-Naegyeong${\lrcorner}$. But ${\ulcorner}$Hwangje-Naegyeong${\lrcorner}$ include the Hypothesis of Armillary Sphere by the astronomical observation and understand the universe with interior-exterior viewpoint. ${\ulcorner}$Hwangje-Naegyeong${\lrcorner}$ describe the circulation of the universe (周天度數) at 365 1/4 terms, the length of daytime and night of the vernal equinox and the autumnal equinox is same and use the The Twenty Eight Constellations by the ecliptic(黃道). It prove that ${\ulcorner}$Hwangje-Naegyeong${\lrcorner}$ observes the celestial body according to the Hypothesis of Armillary Sphere. The Hypothesis of Chaosheavens(宣夜說) appears most is the theory which lately. ${\ulcorner}$Hwangje-Naegyeong${\lrcorner}$ describe Tae Hue(太虛) infinite outer space and the earth is floating by Gi(氣). This with the Hypothesis of Chaosheavens is similar from like this point.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.1
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• pp.65-77
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• 2009

This study conducted a comparative analysis between Koreans and foreigners on how they feel of the 'Oreum' so that the data could be used to conserve and utilize 'Oreum' as a brand of Jeju, which is one of the natural and original sceneries of the island along with Halla Mountain. Four aerial photo slides were selected to be assessed among 18 overlooked views of 'Oreums' through quasi-preliminary and preliminary surveys. The assessment group was divided into native and foreigner groups. Image and preference were measured based on 7 step categorization on 26 adjectives, and factor analysis was implemented. The selected factors from factor analysis reflected that calmness was recognized as common image identification variable to natives and foreigners. However, foreigners choose 'dynamics', 'peculiarity' and 'grandeur' in order to explain the image while Koreans selected words in the order of 'attractiveness', 'grandeur', 'dynamics' and 'peculiarity'. This means Koreans identify the image of 'Oreum' as absolute beauty while foreigners see the dynamics and relative peculiarity as its attractive point. As a result of factor score, preference and multiple regression analysis, Koreans selected 'calmness', 'attractiveness' and 'dynamics' as important variables to explain preference. On the other hand, foreigners choose 'dynamics' and 'calmness' as well as 'evenness', 'peculiarity' and 'simplicity'. This represents that foreigners are highly influenced by the structural peculiarity and simplicity on the image preference.