• Korean Journal of Remote Sensing
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• v.39 no.5_3
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• pp.1031-1042
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• 2023

In this study, a deep learning model was developed to predict the yield of cabbage and radish, one of the five major supply and demand management vegetables, using satellite images of Landsat 8. To predict the yield of cabbage and radish in Gangwon-do from 2015 to 2020, satellite images from June to September, the growing period of cabbage and radish, were used. Normalized difference vegetation index, enhanced vegetation index, lead area index, and land surface temperature were employed in this study as input data for the yield model. Crop yields can be effectively predicted using satellite images because satellites collect continuous spatiotemporal data on the global environment. Based on the model developed previous study, a model designed for input data was proposed in this study. Using time series satellite images, convolutional neural network, a deep learning model, was used to predict crop yield. Landsat 8 provides images every 16 days, but it is difficult to acquire images especially in summer due to the influence of weather such as clouds. As a result, yield prediction was conducted by splitting June to July into one part and August to September into two. Yield prediction was performed using a machine learning approach and reference models , and modeling performance was compared. The model's performance and early predictability were assessed using year-by-year cross-validation and early prediction. The findings of this study could be applied as basic studies to predict the yield of field crops in Korea.

• Journal of Korea Water Resources Association
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• v.56 no.11
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• pp.775-784
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• 2023

With the increasing trend of extreme rainfall that exceeds the design frequency of man-made structures due to extreme weather, it is necessary to review the safety of agricultural reservoirs designed in the past. However, there are no local government-managed reservoirs (13,685) that can be discharged in an emergency, except for reservoirs over a certain size under the jurisdiction of the Korea Rural Affairs Corporation. In this case, it is important to quickly deploy a mobile siphon to the site for preliminary discharge, and this study evaluated the applicability of a mobile siphon with a diameter of 200 mm, a minimum water level difference of 6 m, 420 (m²/h), and 10,000 (m²/day), which can perform both preliminary and emergency discharge functions, to the Yugum Reservoir in Gyeongju City. The test bed, Yugum Reservoir, is a facility that was completed in 1945 and has been in use for about 78 years. According to the hydrological stability analysis, the lowest height of the current dam crest section is 27.15 (EL.m), which is 0.29m lower than the reviewed flood level of 27.44 (EL.m), indicating that there is a possibility of lunar flow through the embankment, and the headroom is insufficient by 1.72 m, so it was reviewed as not securing hydrological safety. The water level-volume curve was arbitrarily derived because it was difficult to clearly establish the water level-flow relationship curve of the reservoir since the water level-flow measurement was not carried out regularly, and based on the derived curve, the algorithm for operating small and medium-sized old reservoirs was developed to consider the pre-discharge time, the amount of spillway discharge, and to predict the reservoir lunar flow time according to the flood volume by frequency, thereby securing evacuation time in advance and reducing the risk of collapse. Based on one row of 200 mm diameter mobile siphons, the optimal pre-discharge time to secure evacuation time (about 1 hour) while maintaining 80% of the upper limit water level (about 30,000 m²) during a 30-year flood was analyzed to be 12 hours earlier. If the pre-discharge technology utilizing siphons for small and medium-sized old reservoirs and the algorithm for reservoir operation are implemented in advance in case of abnormal weather and the decision-making of managers is supported, it is possible to secure the safety of residents in the risk area of reservoir collapse, resolve the anxiety of residents through the establishment of a support system for evacuating residents, and reduce risk factors by providing risk avoidance measures in the event of a reservoir risk situation.

• Journal of Bio-Environment Control
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• v.32 no.4
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• pp.342-352
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• 2023

Ultra-violet (UV) light is one of abiotic stress factors and causes oxidative stress in plants, but a suitable level of UV radiation can be used to enhance the phytochemical content of plants. The accumulation of antioxidant phenolic compounds in UV-exposed plants may vary depending on the conditions of plant (species, cultivar, age, etc.) and UV (wavelength, energy, irradiation period, etc.). To date, however, little research has been conducted on how leaf thickness affects the pattern of phytochemical accumulation. In this study, we conducted an experiment to find out how the antioxidant phenolic content of kale (Brassica oleracea var. acephala) leaves with different thicknesses react to UV-A light. Kale seedlings were grown in a controlled growth chamber for four weeks under the following conditions: 20℃ temperature, 60% relative humidity, 12-hour photoperiod, light source (fluorescent lamp), and photosynthetic photon flux density of 121±10 µmol m^-2 s^-1. The kale plants were then transferred to two chambers with different CO₂ concentrations (382±3.2 and 1,027±11.7 µmol mol^-1), and grown for 10 days. After then, each group of kale plants were subjected to UV-A LED (275+285 nm at peak wavelength) light of 25.4 W m^-2 for 5 days. As a result, when kale plants with thickened leaves from treatment with high CO₂ were exposed to UV-A, they had lower UV sensitivity than thinner leaves. The Fv/Fm (maximum quantum yield on photosystem II) in the leaves of kale exposed to UV-A in a low-concentration CO₂ environment decreased abruptly and significantly immediately after UV treatment, but not in kale leaves exposed to UV-A in a high-concentration CO₂ environment. The accumulation pattern of total phenolic content, antioxidant capacity and individual phenolic compounds varied according to leaf thickness. In conclusion, this experiment suggests that the UV intensity should vary based on the leaf thickness (age etc.) during UV treatment for phytochemical enhancement.

• Journal of Korean Academy of Nursing
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• v.4 no.3
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• pp.33-56
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• 1974

간호를 장래의 전문직으로 택하려고 공부하는 간호학생들은 완전한 성인으로서의 발달 과정중 후기 성년기에 속한다. 이시기는 자아를 발견하고 인간이 무엇을 믿으며 인간의 가치가 무엇인가를 추구하는 중요한 시기이다. 다시 말해서 어른과 어린이의 과도기에 서서 자신의 이상적 가치와 기성사회의 기존 가치를 잘 융화시켜 독립된 인간으로서 성숙하려는 노력의 시기이다. 그러므로 성년기의 갈등은 인생의 어느 시기보다도 그 정도가 심하게 나타난다. 간호학생들은 이상의 일반적인 성년기 발달의 요구 외에도 간호대학이라는 특수한 배움의 여건 때문에 좀 더 심각한 문제에 대두된다. 특히 소아과 간호대학이라는 실습환경은 여러 가지 복잡한 병실 사정으로 많은 긴장감을 주는 학습경험이다. 어린이의 간호에는 그들의 발달과정에 따른 다양한 역활이 요구된다. 또한 병원이라는 낯선 환경과 어머니를 떨어져야하는 두려움으로 불안한 어린이와 그 어린이의 불안과 두려움으로 인해 우울과 죄의식에 있는 어머니의 간호는 여러 면에서 성년기 학생들에게 긴장감을 일으키게 하는 요인이 된다. 본 연구의 문헌조사는 주로 미국 문헌에 나타난 간호 대학생들의 성년기 성숙을 위한 발달의 요구와, 소아병실의 복잡한 여건으로 발생되는 긴장감을 다루고 있다. 문헌을 기초로 하여 저자는 긴장감을 주는 간호활동을 크게 다섯 부군으로 묶었다. 1. 어린이 환자의 신체적 간호, 2. 어린이 환자나 부모와의 원만한 대화와 상호관계를 위한 간호활동 3. 소아병실에서 요구되는 다양한 간호원의 역활 4. 어린이나 부모의 간호에 대한 의뢰심 5. 간호의 가치나 이상적 간호. 연구방법으로는 49개의 폐쇄식 질문 항목을 가진 질문지를 사용하였다. 질문 항목들은 문헌연구에서 소아과 간호학 실습시 학생들이 긴장감을 느낀다고 밝혀진 내용들이 다. 학생들은 자신의 경험을 "긴장감이 없었다. ""긴장감이 있었다. ""심한 긴장감이 있었다. ""실습 중 경험이 없었다. "의 사항 중 택일을 하게 되어 있다. 연구대상으로는 모 대학교 간호대학 학생으로 산부인과 간호학 실습을 마친 후 소아과 간호학 실습 8주를 완료한 4학년 학생 42명이었다. 자료분석의 결과는 대부분의 학생들에게 소아과 간호학 실습은 긴장감을 주는 경험이 있다고 나타났다. 다음은 연구결과 주목할만한 몇 가지 사항들이다. 1. 어린이 환자의 신체적 간호는 성년기 학생들에게 긴장감을 주는 실습 경험이었다. 특별히 심하게 긴장감을 주었던 간호활동은 어린이환자의 상태가 중한 경우로, 장기간 앓는 아이, 선천성 기형이 있는 아이, 회복이 불가능하여 죽게될 아이나 사망하는 경우의 어린이 간호였다. 이 결과는 간호학의 기본과정 즉, 기초간호학이나 내 외과 간호학 실습만으로 소아과 간호학 실습을 위한 충분한 준비가 되지 못한다는 것을 뜻 할 수도 있다. 한편, 문헌연구에서 밝힌바와 같이 어리고 연약해 보이는 어린이들의 신체조건이 학생들의 간호활동을 어렵게 하는 경우도 될 수 있겠다. 2. 간호학생들의 어린이 환자와의 대화나 원만한 인간관계에서의 긴장감은 이 연구결과로 평가나 제언이 힘들다. 조사결과에서 학생들은 주로 어린이의 상태가 좋지 않은 경우에 심한 긴장감을 가졌고 일반적인 간호의 경우에는 별로 긴장감이 없었다. 이것은 질병의 상태나 화제, 이야기 할 때의 상황에 따라 긴장감의 여부가 달라질 수 있다는 결론이 되겠다. 3. 소아병실에서의 다양한 역활을 수행하는 것은 비교적 긴장감이 많이 생기는 간호활동으로 나타났다. 그러나 재미있는 사실은 학생들이 간호원으로서의 전문가적인 입장에서, 환자나 보호자를 가르칠때는 별로 문제가 없었으나 어린이 기르는 방법이나 어린이 이해면에서 좀 더 잘 안다고 생각되는 어머니가 지켜 볼때의 어린이 간호에는 긴장감을 가진다는 사실이다. 이것은 Jewett의 연구에서 밝힌바와는 상반되는 결과다. 그의 연구에서 학설들은 부모나 어머니들에 의해 전문가로서 인정받고 기대되는 경우가 제일 어려운 경험이 있다고 밝혔다. 4. 어린이 환자나 그들 부모의 간호에 대한 의뢰심은 학생들에게 심한 긴장감을 주는 경험이 있다. 특히 신체적 간호에 대해 의뢰하는 경우에는 더 심한 긴장감을 준다고 표현한다. 일반적으로 부모가 병실에 상주하는 경우에는 그들의 의뢰심이 심하며 이것은 학생들에게 감당하기 힘든 긴장과 어려움을 주게된다. 왜냐하면 성년기의 학생들은 그들 자신이 먼저 타인에게서 이해받기를 원하며 또 관용을 베풀어주기를 원하는데 그것을 남에게 주어야 하는 입장은 학생들을 긴장되게 하는 실습활동인 것이다. 5. 학생들은 그들이 배운 간호의 이상이나 가치가 실습지에서의 여러 경우와 맞지 않는 것을 보았을 때 극심한 긴장감을 갖는다고 밝혔다. 의사나 병원 행정의 사실이 자신의 이상과 맞지 않는다는 것보다는 간호원의 간호업무의 차이에서 더 비판적인 반응을 보였다. 대부분의 성년기 학생들은 그들의 이상적인 간호원상을 그들의 선배나 실무 간호원 중에서 찾으려는 시기에 그들의 간호활동이 이론과 다른 점이나 학생 자신의 소아과 간호의 가치와 다른 것을 보았을 때는 심한 반감과 긴장감을 갖게된다. 이 문제는 어린 사람이 윗 어른과 함께 동료의식을 갖고 일하기 어려운 한국적 사회구조 때문에 더 심하게 긴장감을 주는 경험인지도 모른다. 선배 간호원의 전문인으로서의 권위와 어린이 환자 보호자의 어른으로서의 권위 사이에서 자신의 이상과 가치의 추구는 용이하지 않으며 내적 갈등은 어쩔수 없는 일 일 것이다. 6. 대부분 높은 백분율의 긴장 반응은 죽음이나 환자의 사망에 관련된 간호활동 항목에서 나타났다. 이 연구의 대상 학생들은 2, 3학년에서 죽음에 대한 강의를 들었지만 이 연구 결과에 의하면 충분한 학습 경험이 주어진 것 같지 않다. 어떠한 경우의 죽음에라도 어린이 환자나 그 보호자들의 심리를 잘 이해하고 반응을 잘 관찰해서 적절한 간호를 해 줄 수 있는 다양한 방법의 학습 경험이 필요하다고 보겠다. 7. 학생들의 긴장도가 어린이 간호에 더 심한가, 보호자 간호에 더 심한가를 알기 위한 비교 결과는 비교적 비슷한 정도로 나타났다. 8. 학생들의 소아과 간호학 실습시의 긴장도는 과거의 병실 실습기간의 장, 단이나 가정에서의 어린인 간호의 경험과는 별 연관성이 없었다. 연구의 대상자가 적기 때문에 단정을 하기는 힘이 들지만 소아과 간호학 실습이 다른 병실의 실습과는 분리되어서 완전히 다르게 다루어 져야만 하며 간호교육자들의 주의 깊은 관심과 노력이 필요한 실습교육이 라 하겠다. 이상의 전반적인 고찰에 의하면 한국 성년기 간호학생들의 소아과 간호학 실습은 미국의 경우와 마찬가지로 긴장감을 주는 경험이다. 문화배경의 다른 점은 무시하고라도 Davis와 Oleson이 결론한 바와 같이 "간호대 학생은 어디를 막론하고 다 같은 성격과 문제를 가지고 있다. " 앞으로 보다 효과적인 학생들의 소아과 간호학 실습을 위한 연구를 위해 다음의 몇 가지를 본 연구의 결과를 가지고 제언한다. 1. 보다 여러 지역에서 다양한 교육 방법을 가진 학교의 학생을 대상으로 한 연구의 필요성. 2. 학생들이 실습 전 선입견이나 이미 들어서 생긴 긴장감의 개입 여부를 밝힐 수 있는 연구. 3. 학생 개인의 과거 경침이 긴장감 유발에 미치는 영향을 위한 연구 4. 이 연구의 결과를 입증할 수 있는 종단적 연구. 5. 이 연구에서 나타난 긴장감이 학습 행위에 미치는 영향을 알기 위한 관찰적 연구. 이 연구를 위해 많은 도움을 주셨던 보스턴대학의 Dr. Kennedy와 연세대학의 여러 선생님께 심심한 감사를 드립니다.

• Applied Microscopy
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• v.30 no.2
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• pp.213-232
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• 2000

The development of the knee joint was studied by electron microscopy in human fetuses ranging from 20 mm to 260 mm crown-rump length ($7\sim30$ weeks of gestational age). The appearance of the primordium of the meniscus and cruciate ligament was conspicuous as the mesenchymal cells , preceeding that of joint space at 30 mm fetus. The primitive joint cavity was first seen in the interzone from the 40 mm fetus and its intermediate layer proceeded developing as a narrow cleft which was closely incorporated with two chondrogenic layers. Poorly differentiated mesenchymal cells of the meniscus at 40 mm fetus containing predominantly free ribosomes differentiated into fibroblasts at 60 mm fetus. By 100 mm fetus, the fibroblast in inner zone of the meniscus presented as oval profiles with a short cell processes, whereas middle and peripheral zones presented as elongated cells. Differentiation of the synovial membrane coincided with clarification of the joint cavity When dilatation of the synovial cavity occurred, the two types of synovial cells were identified at 60 mm fetus. By 100 mm fetus a majority of the intimal cells were B-type. B-type cells were clearly distinguishable from A-type cells by their content of extensive rough endoplasmic reticula and well developed Golgi complexes. In contrast, A-type cells had numerous filopodia, pinocytotic vesicles, lysosomes and large vacuoles. At 260 mm fetus the B-type cells were also a majority of intimal cells. At 260 mm fetus the inner zone of the meniscus was filled with parallel oriented fascicles of collagenous fibers and oval fibroblasts. The middle zone was constituted of parallel and radially arranged fibers and fibroblasts. The outer zone was populated by elongated fibroblasts encircled by crossed collagenous fibers with the blood vessels. At 30 mm fetus the fibroblasts of the cruciate ligament contained rough endoplasmic reticula and mitochondria. Collagen fibrils were noted within narrow cytoplasmic processes which were continued with the extracellular space. Collagen fibrils of ligament were filled in the bulk of extracellular space at 100 mm fetus. By $150\sim260mm$ fetus, the cruciate ligaments were constituted of longitudinally oriented bundle of collagen fibrils with irregular rows of round cells between.

• Clinical and Experimental Pediatrics
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• v.48 no.7
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• pp.737-744
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• 2005

Purpose : Infants and children with cardiovascular diseases often present with respiratory symptoms. However, missed or delayed evaluation for potential airway problem may complicate overall prognosis. The aim of this study is to determine the clinical characteristics of these patients and explore the cause of airway problem. Methods : We reviewed the medical records of 64 patients(M : F=33:31, mean age : $6.3{\pm}7.5$ months) whose airway problems were proven by computed tomography or bronchoscopy in perioperative periods at the Asan Medical Center from January 1997 to June 2004. Patients were divided into two groups based on the duration of ventilator care : ${\leq}7$ days(group 1 : 23 cases, M : F=10 : 13) and >7 days(group 2 : 41 cases, M : F=23 : 18). Results : The patients in group 2 significantly developed more post-operative respiratory symptoms than group 1(P<0.001) and had more airway problems including extrinsic obstruction, intrinsic anomaly, and combined problem than group 1 although not significantly different(P=0.082). Among underlying diseases, the most common diseases were vascular anomaly(26.2 percent) and aortic arch anomaly(26.2 percent) in group 1 and pulmonary atresia with ventricular septal defect(22.4 percent) in group 2. The most frequent respiratory symptoms were recurrent wheezing pre-operatively and failure of ventilator weaning post-operatively. The major types of airway anomaly were tracheomalacia and tracheal stenosis(in each case 18.2 percent). Nineteen patients with persistent airway problems underwent aortopexy or other vascular correction. Of the 19 patients, 13(68.4 percent) were improved, but 2 failed in weaning ventilator and 4 died of non-airway problems. Conclusion : Early evaluation and treatment for potential airway problems may affect natural or surgical prognosis in patients with cardiovascular diseases presenting with respiratory symptoms.

• Journal of Periodontal and Implant Science
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• v.37 no.sup2
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• pp.427-445
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• 2007

To improve osseointegration at the boneto-implant interface, several studies have been carried out to modify titanium surface. Variations in surface texture or microtopography may affect the cellular response to an implant. Osteoblast-like cells attach more readily to a rougher titanium surface, and synthesis of extracellular matrix and subsequent mineralization were found to be enhanced on rough or porous coated titanium. However, regarding the effect of roughened surface by physical and mechanical methods, most studies carried out on the reactions of cells to micrometric topography, little work has been performed on the reaction of cells to nanotopography. The purpose of this study was to examme the response of osteoblast-like cell cultured on blasted surfaces and alkali treated surfaces, and to evaluate the influence of surface texture or submicro-scaled surface topography on the cell attachment, cell proliferation and the gene expression of osteoblastic phenotype using ROS 17/2.8 cell lines. In scanning electron micrographs, the blasted, alkali treated and machined surfaces demonstrated microscopic differences in the surface topography. The specimens of alkali treatment had a submicro-scaled porous sur-face with pore size about 200 nm. The blasted surfaces showed irregularities in morphology with small(<10 ${\mu}m$) depression and indentation among flatter-appearing areas of various sizes. Based on profilometry, the blasted surfaces was significantly rougher than the machined and the alkali treated surfaces (p$TiO_2$) were observed on alkali treated surfaces, whereas not observed on machined and blasted surfaces. The attachment morphology of cells according to time was observed by the scanning electron microscope. After 1 hour incubation, the cells were in the process of adhesion and spreading on the prepared surfaces. After 3 hours, the cells on all prepared surfaces were further spreaded and flattened, however on the blasted and alkali treated surfaces, the cells exhibited slightly irregular shapes and some gaps or spaces were seen. After 24 hours incubation, most cells of the all groups had a flattened and polygonal shape, but the cells were more spreaded on the machined surfaces than the blasted and alkali treated surfaces. The MTT assay indicated the increase on machined, alkali treated and blasted surfaces according to time, and the alkali treated and blasted surfaces showed significantly increased in optical density comparing with machined surfaces at 1 day (p<0.01). Gene expression study showed that mRNA expression level of ${\alpha}\;1(I)$ collagen, alkaline phosphatase and osteopontin of the osteoblast-like cells showed a tendency to be higher on blasted and alkali treated surfaces than on the machined surfaces, although no siginificant difference in the mRNA expression level of ${\alpha}\;1(I)$ collagen, alkaline phosphatase and osteopontin was observed among all groups. In conclusion, we suggest that submicroscaled surfaces on osteoblast-like cell response do not over-ride the one of the surface with micro-scaled topography produced by blasting method, although the microscaled and submicro-scaled surfaces can accelerate osteogenic cell attachment and function compared with the machined surfaces.

• The Korean Journal of Air & Space Law and Policy
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• v.30 no.2
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• pp.469-497
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• 2015

In 2009 Iridium 33, a satellite owned by the American Iridium Communications Inc. and Kosmos-2251, a satellite owned by the Russian Space Forces, collided at a speed of 42,120 km/h and an altitude of 789 kilometers above the Taymyr Peninsula in Siberia. NASA estimated that the satellite collision had created approximately 1,000 pieces of debris larger than 10 centimeters, in addition to many smaller ones. By July 2011, the U.S. Space Surveillance Network(SSN) had catalogued over 2,000 large debris fragments. On January 11, 2007 China conducted a test on its anti-satellite missile. A Chinese weather satellite, the FY-1C polar orbit satellite, was destroyed by the missile that was launched using a multistage solid-fuel. The test was unprecedented for having created a record amount of debris. At least 2,317 pieces of trackable size (i.e. of golf ball size or larger) and an estimated 150,000 particles were generated as a result. As far as the Space Treaties such as 1967 Outer Space Treaty, 1968 Rescue Agreement, 1972 Liability Convention, 1975 Registration Convention and 1979 Moon Agreement are concerned, few provisions addressing the space environment and debris in space can be found. In the early years of space exploration dating back to the late 1950s, the focus of international law was on the establishment of a basic set of rules on the activities undertaken by various states in outer space.. Consequently environmental issues, including those of space debris, did not receive the priority they deserve when international space law was originally drafted. As shown in the case of the 1978 "Cosmos 954 Incident" between Canada and USSR, the two parties settled it by the memorandum between two nations not by the Space Treaties to which they are parties. In 1994 the 66th conference of International Law Association(ILA) adopted "International Instrument on the Protection of the Environment from Damage Caused by Space Debris". The Inter-Agency Space Debris Coordination Committee(IADC) issued some guidelines for the space debris which were the basis of "the UN Space Debris Mitigation Guidelines" which had been approved by the Committee on the Peaceful Uses of Outer Space(COPUOS) in its 527th meeting. On December 21 2007 this guideline was approved by UNGA Resolution 62/217. The EU has proposed an "International Code of Conduct for Outer Space Activities" as a transparency and confidence-building measure. It was only in 2010 that the Scientific and Technical Subcommittee began considering as an agenda item the long-term sustainability of outer space. A Working Group on the Long-term Sustainability of Outer Space Activities was established, the objectives of which include identifying areas of concern for the long-term sustainability of outer space activities, proposing measures that could enhance sustainability, and producing voluntary guidelines to reduce risks to long-term sustainability. By this effort "Guidelines on the Long-term Sustainability of Outer Space Activities" are being under consideration. In the case of "Declaration of Legal Principles Governing the Activities of States in the Exp1oration and Use of Outer Space" adopted by UNGA Resolution 1962(XVIII), December 13 1963, the 9 principles proclaimed in that Declaration, although all of them incorporated in the Space Treaties, could be regarded as customary international law binding all states considering the time and opinio juris by the responses of the world. Although the soft law such as resolutions, guidelines are not binding law, there are some provisions which have a fundamentally norm-creating character and customary international law. In November 12 1974 UN General Assembly recalled through a Resolution 3232(XXIX) "Review of the role of International Court of Justice" that the development of international law may be reflected, inter alia, by the declarations and resolutions of the General Assembly which may to that extend be taken into consideration by the judgements of the International Court of Justice. We are expecting COPUOS which gave birth 5 Space Treaties that it could give us binding space debris mitigation measures to be implemented based on space debris mitigation soft law in the near future.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.12
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• pp.1560-1570
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• 2007

The purpose of this study was to investigate the differences according to lifestyle in anthropometric measurement, dietary attitude, health-related behaviors and nutrient intake among the college students. The subjects were 994 nation-wide college students (male: 385, female: 609) and divided into 7 clusters (PEAO: passive economy/appearance-oriented type, NCPR: non-consumption/pursuit of relationship type, PTA: pursuit of traditional actuality type, PAT: pursuit of active health type, UO: utility-oriented type, POF: pursuit of open fashion type, PFR: pursuit of family relations type). A cross-sectional survey was conducted using a self administered questionnaire, and the data were collected via Internet or by mail. The nutrient intake data collected from food record were analyzed by the Computer Aided Nutritional Analysis Program. Data were analyzed by a SPSS 12.0 program. Average age of male and female college students were 23.7 years and 21.6 years, respectively. Most of the college students had poor eating habits. In particular, about 60% of the PEAO group has irregularity in meal time. The students in PAH and POF groups showed significantly higher consumption frequency of fruits, meat products and foods cooked with oil compared to the other groups. As for exercise, drinking and smoking, there were significant differences between PAH and the other groups. Asked for the reason for body weight control, 16.2% of NCPR group answered "for health", but 24.8% of PEAO group and 26.3% of POF group answered "for appearance". Calorie, vitamin A, vitamin $B_2$, calcium and iron intakes of all the groups were lower than the Korean DRIs. Female students in PTA group showed significantly lower vitamin $B_1$ and niacin intakes compared to the PFR group. Therefore, these results provide nation-wide information on health-related behaviors and nutrient intake according to lifestyles among Korean college students.