• 대한인간공학회지
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• 제35권4호
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• pp.293-305
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• 2016

Objective: This study aims to measure cognitive load levels by analyzing the EEG of Koreans and foreigners, when they read a Korean text with care selected by level from the grammar and vocabulary aspects, and compare the cognitive load levels through quantitative values. The study results can be utilized as basic data for more scientific approach, when Korean texts or books are developed, and an evaluation method is built, when the foreigners encounter them for learning or an assignment. Background: Based on 2014, the number of the foreign students studying in Korea was 84,801, and they increase annually. Most of them are from Asian region, and they come to Korea to enter a university or a graduate school in Korea. Because those foreign students aim to learn within Universities in Korea, they receive Korean education from their preparation for study in Korea. To enter a university in Korea, they must acquire grade 4 or higher level in the Test of Proficiency in Korean (TOPIK), or they need to complete a certain educational program at each university's affiliated language institution. In such a program, the learners of the Korean language receive Korean education based on texts, except speaking domain, and the comprehension of texts can determine their academic achievements in studying after they enter their desired schools (Jeon, 2004). However, many foreigners, who finish a language course for the short-term, and need to start university study, cannot properly catch up with university classes requiring expertise with the vocabulary and grammar levels learned during the language course. Therefore, reading education, centered on a strategy to understand university textbooks regarded as top level reading texts to the foreigners, is necessary (Kim and Shin, 2015). This study carried out an experiment from a perspective that quantitative data on the readers of the main player of reading education and teaching materials need to be secured to back up the need for reading education for university study learners, and scientifically approach educational design. Namely, this study grasped the difficulty level of reading through the measurement of cognitive loads indicated in the reading activity of each text by dividing the difficulty of a teaching material (book) into eight levels, and the main player of reading into Koreans and foreigners. Method: To identify cognitive loads indicated upon reading Korean texts with care by Koreans and foreigners, this study recruited 16 participants (eight Koreans and eight foreigners). The foreigners were limited to the language course students studying the intermediate level Korean course at university-affiliated language institutions within Seoul Metropolitan Area. To identify cognitive load, as they read a text by level selected from the Korean books (difficulty: eight levels) published by King Sejong Institute (Sejonghakdang.org), the EEG sensor was attached to the frontal love (Fz) and occipital lobe (Oz). After the experiment, this study carried out a questionnaire survey to measure subjective evaluation, and identified the comprehension and difficulty on grammar and words. To find out the effects on schema that may affect text comprehension, this study controlled the Korean texts, and measured EEG and subjective satisfaction. Results: To identify brain's cognitive load, beta band was extracted. As a result, interactions (Fz: p =0.48; Oz: p =0.00) were revealed according to Koreans and foreigners, and difficulty of the text. The cognitive loads of Koreans, the readers whose mother tongue is Korean, were lower in reading Korean texts than those of the foreigners, and the foreigners' cognitive loads became higher gradually according to the difficulty of the texts. From the text four, which is intermediate level in difficulty, remarkable differences started to appear in comparison of the Koreans and foreigners in the beginner's level text. In the subjective evaluation, interactions were revealed according to the Koreans and foreigners and text difficulty (p =0.00), and satisfaction was lower, as the difficulty of the text became higher. Conclusion: When there was background knowledge in reading, namely schema was formed, the comprehension and satisfaction of the texts were higher, although higher levels of vocabulary and grammar were included in the texts than those of the readers. In the case of a text in which the difficulty of grammar was felt high in the subjective evaluation, foreigners' cognitive loads were also high, which shows the result of the loads' going up higher in proportion to the increase of difficulty. This means that the grammar factor functions as a stress factor to the foreigners' reading comprehension. Application: This study quantitatively evaluated the cognitive loads of Koreans and foreigners through EEG, based on readers and the text difficulty, when they read Korean texts. The results of this study can be used for making Korean teaching materials or Korean education content and topic selection for foreigners. If research scope is expanded to reading process using an eye-tracker, the reading education program and evaluation method for foreigners can be developed on the basis of quantitative values.

• 한국초지조사료학회지
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• 제19권1호
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• pp.41-48
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• 1999

본 시험은 원형베일러를 이용한 생볏짚 사일리지의 조제 가능성을 구명하고 적정 첨가제를 선발하기 위하여 1997년 10월부터 1998년 6월까지 축산기술연구소 초지사료과에서 실시하였다. 첨가제는 생볏짚을 원형베일로 만들기전 무처리, 개미산, 당밀, 당밀+요소 및 젖산균제 등 5처리를 두고 난괴법 3반복으로 수행하였으며 사일리지 품질과 가축 섭취량 등을 조사하였다. 조단백질 함량은 당밀+요소 처리구에서 가장 높았으며 소화율은 당밀 및 젖산균 처리구에서 증가하였다. 건물률에 있어서는 개미산 처리구가 가장 높았고 대조구에서 가장 낮게 나타났으며 첨가제 처리간에는 차이가 없었다. 그러나 산도(pH)는 당밀 및 젖산균제 처리구에서 대조구보다 낮게 나타났다. 유기산 함량은 전체적으로 2%이하로 낮게 나타났으며, 젖산 함량은 당밀 및 젖산균제 처리구에서 유의적으로 증가하였고(P<0.05) 낙산 함량은 감소하였다. 암모니아태 질소의 함량은 당밀+요소 처리구에서 유의적으로 높았으며 당밀 및 젖산균제 처리구에서 10% 이하로 낮게 나타났다. 7일간의 가축 급여시험에서는 젖산균제를 처리한 생볏짚 원형베일 사일리지에서 두당 섭취량이 무처리 원형베일 사일리지와 건조볏짚에 비해 높게 나타났다. 생볏짚 원형베일 사일리지 생산비는 수거면적이 넓어짐에 따라 생산비가 크게 낮아졌다. 이상의 결과를 종합하여 볼 때 생볏짚을 원형베일 사일리지로 조제시 당밀 또는 젖산균제를 첨가할 때 가장 우수한 사일리지를 조제할 수 있었고 젖산균제 처리시 가축 섭취량도 증가되는 것으로 나타났다.

• 한국축산시설환경학회지
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• 제10권3호
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• pp.141-154
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• 2004

자연에너지인 태양열을 동력원으로 하여 구동되는 물펌프는 물이 많이 필요한 여름철에 과 열원인 태양에너지가 강하므로 매우 이상적인 장치라 할 수 있다. 본 연구에서는 태양열 물펌프의 자동화운전을 실현하고자 작동물질의 압력변화를 감지하여 자동 운전되도록 하였으며, 이에 필요한 제어논리를 개발하고 회로론 구성하였다. 실험에서는 장치를 제작. 실험, 분석하였고 분석항목은 양수량과 효율, 압력, 온도를 분석하였다. 또한 자동화에 필수적인 응축기 진공을 위한 응축기의 최소 전열면적을 설계하였으며, 그 결과를 정리하면 다음과 같다. 1. 복사에너지를 동력으로 변환하여 물을 양수할 수 있었고, 자동화 제어회로에 의해 사이클을 반복할 수 있었다. 2 양수는 60분 동안에 13사이클을 수행하였으며, 사이클 당 소요시간은 약 4.9분이었다. 총 양수량은 69,200cc, 사이클 당 평균 5,320cc를 양수하였다. 이 과정동안 장치의 열효율은 $0.030\%$로 나타났다. 3. 실험과정에서 기액 분리탱크 내의 작동물질 증기의 온도는 물탱크로 증기를 배출하기 전후에 따라 약 $41\~49^{\circ}C$ 범위에 있었으며, 상당히 균일하게 변동하고 있었다. 물탱크와 공기탱크내의 온도는 약 $30^{\circ}C$ 정도 부근에서 유지되고 있었으며, 응축기 냉각수공급온도는 실험기간 중 $10\~13^{\circ}C$ 범위를 나타내었다. 응축기 출구온도는 $14\~17^{\circ}C$ 정도로서 응축기 냉각수의 입출구 온도차는 실험초기를 제외하면 약 $4^{\circ}C$ 전후로 나타났다 4. 기액 분리탱크 내의 압력은 자동화 프로그램 된 범위인 150$\~$450hPa(gauge)를 매우 정확하게 유지하였으며, 공기탱크내의 압력은 약 1200hPa로 나타났다. 응축기내의 압력은 약 600hPa로서 진공을 잘 유지함으로서 사이클을 반복하는데 문제가 없었다. 5. 한국의 전국 하루 평균 3.488kWh/($m^2{\cdot}day$)의 태양에너지를 기준으로 장치의 열효율이 $0.1\%$를 적용하고 전 양정을 10m로 보면 태양열복사 단위면적 $m^2$ 당 약 128kg의 물을 양수할 수 있을 것으로 예상된다.

• Asian-Australasian Journal of Animal Sciences
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• 제22권6호
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• pp.836-842
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• 2009

The objectives of this study were to evaluate potential benefits of intercropping of corn with runner bean for a smallsized farming system, based on land equivalent ratio (LER) and silage yield and quality of corn intercropped with runner bean (Phaseolus vulgaris L.), in arid conditions of Turkey under an irrigation system. This experiment was established as a split-plot design in a randomized complete block, with three replications and carried out over two (consecutive) years in 2006 and 2007. Seven different mixtures (runner bean, B and silage corn sole crop, C, 10% B+90% C, 20% B+80% C, 30% B+70% C, 40% B+60%C, and 50% B+50%C) of silage corn-runner bean were intercropped. All of the mixtures were grown under irrigation. The corn-runner bean fields were planted in the second week of May and harvested in the first week of September in both years. Green beans were harvested three times each year and green bean yields were recorded each time. After the 3rd harvest of green bean, residues of bean and corn together were randomly harvested from a 1 $m^{2}$ area by hand using a clipper when the bean started to dry and corn was at the dough stage. Green mass yields of each plot were recorded. Silages were prepared from each plot (triplicate) in 1 L mini-silos. After 60 d ensiling, subsamples were taken from this material for determination of dry matter (DM), pH, organic acids, chemical composition, and in vitro DM digestibility of silages. The LER index was also calculated to evaluate intercrop efficiencies with respect to sole crops. Average pH, acetic, propionic and butyric acid concentrations were similar but lactic acid and ammonia-N levels were significantly different (p<0.05) among different mixtures of bean intercropped with corn. Ammonia-N levels linearly increased from 0.90% to 2.218 as the percentage of bean increased in the mixtures up to a 50:50 seeding ratio. While average CP content increased linearly from 6.47 to 12.45%, and average NDF and ADF contents decreased linearly from 56.17 to 44.88 and from 34.92 to 33.51%, respectively, (p<0.05) as the percentage of bean increased in the mixtures up to a 50:50 seeding ratio, but DM and OM contents did not differ among different mixtures of bean intercropped with corn (p>0.05). In vitro OM digestibility values differed significantly among bean-corn mixture silages (p<0.05). Fresh bean, herbage DM, IVOMD, ME yields, and LER index were significantly influenced by percentage of bean in the mixtures (p<0.01). As the percentage of bean increased in the mixtures up to a 50:50 seeding ratio, yields of fresh bean (from 0 to 24,380 kg/ha) and CP (from 1,258.0 to 1,563.0 kg/ha) and LER values (from 1.0 to 1.775) linearly increased, but yields of herbage DM (from 19,670 to 12,550 kg/ha), IVOMD (from 12,790 to 8,020 kg/ha) and ME (46,230 to 29,000 Mcal/ha) yields decreased (p<0.05). In conclusion, all of the bean-corn mixtures provided a good silage and better CP concentrations. Even though forage yields decreased, the LER index linearly increased as the percentage of bean increased in the mixture up to a 50:50 seeding ratio, which indicates a greater utilization of land. Therefore, a 50:50 seeding ratio seemed to be best for optimal utilization of land in this study and to provide greater financial stability for labor-intensive, small farmers.

• Journal of Biosystems Engineering
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• 제2권1호
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• pp.7-24
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• 1977

This paper is the forth and fifth one of the study on balanced type oscillating mole drainer. In the light of the results from previous reports about the model tests, some design criteria were established and a prototype machine was set up for experimental purpose. Motion characteristics and functionof the each parts of the machine were checked and analyzed. After that, performance tests of the prototype machine were carried out in thefield. Obtained results are summarized as follows ; 1. Ten centimeter of the bullet diameter was determined so as to be able to attach it to the tractors with capacity of 30 PS to 40 PS. 2. To maintain the balance between the moments of the front shank and rear shank, the oscillating amplitude of the rear bullet was determined to be larger than that of the front bullet. At the same time , the oscillating direction of the rear bullet was designed with the inclines of ten to thirty degrees. 3. An octagonal dynamo transduced was developed for measuring the compressive force of the upper link is measuring the draft force of the machine. Acceptable linear relationship between forces and strain responses from O.D.T. was obtained. 4. Analysing the balancing mechanism of the acting part of the machine , it was found that the total draft force of the machine was equal to the difference between the sum of the draft force produced from the right and left side bending moments of the lower drawber and the compressive force on the upper link. 5. There are acceptable linear relationship between the strain and twisting moment by driving shaft, and between strain and shank moment. Above results enable us to carry out the field experiment with prototype machine. 6. When the test machine was used in the field, it was possible to reduce the oscillating acceleration by forty percent in average as compared it with the single bullet mole drainer. 7. When the test machine was used under the oscillating condition, the dratt torce was reduced by 27 percent to 59 percent as compared it with the test machine under non-oscillating condition, while the draft force was increased by 7 percent to 20 percent as compared it with the mole drainer having oscillating single bullet. The reasoning behind this fact was considered as the resistance force due to the rear shank and bullet. 8. As the amplitude and frequency of the bullet were increased, the torque was increased accordingly. This tendency could be varied with the various characteristics of the given soils. And the larger frequency and amplitute, the more increasing oscil\ulcornerlating power but decreasing draft brce were needed, and draft force was increased as the velocity was increased.9. When the amplitude of the rear bullet was designed to be larger than that of the front bullet, the minimum value of the moment was lowered and oscillating acceleration was reduced. And when the oscillating direction of the rear bullet was declined back\ulcornerwards, oscillating acceleration was increased along with the increasing angle of decli\ulcornernation. When the test machine was operated in high speed, the difference between maximum moments and minimum ones became narrow. This varying magnitude of moments appeared on the moment oscillogram seems to be correlated to the oscillating acceleration and draft force. 10. From the analysis of variance, it was found that those factors such as frequency, amplitude, and operating velocity significantly affected in the oscillating acceleration, the draft resistance, the torque, the moment, and the total power required. And interaction between frequency and amplitude affected in the oscillating acceleration. 11. Within the given situation of this study, the most preferable operating conditions of the test machine were 7 Hz in oscillating frequency, 0.54 m/sec in operating velocity, and 39.1 mm in oscillating amplitude of front and rear bullets. However, it is necessary to select the proper frequency and magnitude of oscillation depending on the soil properties of the field in which the mole drainer is practiced by use of a bal1nced type oscillating mole drainer. 12. It is recommended that a comparative study of the mole drainers would be performed in the near future using two separate balanced oscillating bullet with the one which is operated by oscillating the movable bullet in a single cylinder or other balanced type which may be single oscillating bullet with spring, damper or balancing weight, and that of thing. To expand the applicability of the balanced type oscillating mole drainer in practical use, it is suggested to develop a new mechanism which perform mole drain with vinyl pipe or filling material such as rice hull.

• Journal of Chest Surgery
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• 제37권9호
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• pp.742-748
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• 2004

On-X 판막은 비교적 최근 소개된 이엽성 기계판막으로 국립의료원에서 시행한 28명의 환자의 단기 임상성적을 통하여 판막의 안정성과 유용성을 보고하고자 한다. 대상 및 방법: 1999년 5월부터 2003년 5월까지 On-X 판막을 이용하여 32예의 판막치환술을 받은 28명의 연속적인 환자를 대상으로 하였으며 승모판막 치환 12예, 대동맥 판막치환 10예 그리고 승모판막 및 대동맥판막치환 6예이었다. 수술 후 발생한 합병증 및 사망률에 대한 정의 및 분류는 심장 판막수술에 대한 AATS/STS 지침에 근거하여 분석하였다. 전체 추적기간은 64환자-년이었고 평균 27개월이었다 결과: 수술 후 30일 이내의 조기 사망률은 7.14% (2/28)이었으며 만기사망은 없었다. 2년 생존율은 전체적으로 92.86$\pm$4.87% 이며 대동맥판막치환술이 90$\pm$9.49%, 이중판막치환술이 83.3$\pm$1.52%, 승모판막치환술이 100%로 나타났다. 혈전 색전증이 가장 많은 합병증으로 2예가 있었으며 모두 승모판막치환 증례에서 발생되어 Linearized Ratio는 총 3.17%/환자-년이었으며 승모판막만을 보면 6.5%/환자-년이었고 항응고제와 관련 된 출혈, 판막폐쇄증, 판막주위누출, 심내막염 등의 합병증의 모든 예에서 발생되지 않아 판막관련 합병증이 없는 2년간의 빈도는 84.85 $\pm$ 10.75% (freedom from valve related complication)이었다. 수술전 NYHA Class III 이상인 증례가 24예(85.71%)이었으나 수술 후에는 NYHA Class I 또는 II에 속하는 증례가 25예로 89.29%를 보였다. 용혈척도로서 혈색소 수치, 혈장 LDH, 망상적혈구수치, 간접 빌리루빈치는 수술 3개월 후 검사에서 모두 정상수치를 보였다. 수술 후 3개월 추적관찰 시 시행한 심초음파상 승모판막의 최대 압력차는 6.1 $\pm$ 1.8 mmHg, 평균 압력차는 3.0$\pm$0.6 mmHg이었고 유효 개구 면적은 판막 직경 27 mm, 29 mm, 31 mm, 33 mm 각각 2.54$\pm$0.56 $m^2$, 2.39 $\pm$0.73 $m^2$, 2.34 $\pm$0.55 $m^2$, 2.40$\pm$0.63 $m^2$이었다. 대동맥판막의 최대 압력차는 21.1$\pm$14.12 mmHg,평균 압력차는 12.3$\pm$6.52 mmHg. 결론： On-X 판막수술 후 사망률, 판막관련합병증, 도플러 심초음파상 다른 판막들과 큰 차이를 보이지 않은 점과 NYHA Class의 호전과 정상수치를 유지하는 용혈지표를 고려한다면 비교적 좋은 결과를 보였으며 증례의 축적과 장기간의 임상분석이 이루어지면 안전하고 유용한 판막으로 입증될 것이라고 생각한다.

• 복식
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• 제26권
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• pp.175-206
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• 1995

The costume culture of China is as old and varied as her long history. As China is a multiracial nation and consists of fifty-six min-ority races including Han race, there are not only fifty-six different costumes in China but each races' costume habit is very different. Therefore, Chinese penninsula can be considered an enor-mous exhibition center of the costumes. This study undertook on the assumption that the costumes' mainstream of Korea and east-northern Asia as well as that of China could be examined by investigating the minority races' costumes in the east-and west-northern areas of China. The process of evolution of the costume of a particular people, country or area is subject not only to constraints related to geography such as climate, topography or local products but is also affected by numorous environmental influences including cultural, economic, social and even pol-itical ones in terms of the selection of material, styling, color and standard of tailoring. In other words, things like philosophy of life, religious be-lief, aesthetic outlook, moral code, class system, degree of affluence, and cultural exchange will all be reflected directly or indirectly by features of a people's or country's style costume. Of course, there are several factors affecting to the style of costume of the minority people in China. However, the only three factors-geo-graphical and environmental, production method, and religious belef-will be touched in this study. First of all, the geograghical and eenviron-mental factor would be the decisive one because the costume should be designed to overcome the constraints of climate and geographical environ-ments. Accordingly, each race has an unique style of costume. The costume of the minority races in the northern parts are loose and wide, and made of warm furs. For instance, Mongolian robe has the quality of anti-wind, anti-cold and warmness, and the width of a sleeve is narrow and long. Secondly, the costume style can be said to be limited by the production pattern, when the geo-graphical environment was affected to decide the costume style, the production pattern was together affected to it . In case of Mongolian robe, they should satisfy the dual condition as the practical function. One is the condition that they should be fitted to the climate, and the other is the condition that they should be suit-able to the nomadic life. Mongolian robes are suitable to the nomadic peoples because they are designed for not only overcoming the cold wind and weather but being used as the bedquit at night. The costumes of Hoche people was made of the skin of the fish and wild animals because of their main means of living being fishing and hunting. Accordingly, their costumes are dur-able, warm and water-proof. Finally, the style of the costume is affected by the religious belief. In other words, the pattern in fashion is closely related with the religious be-lief or ancestor worship and nature worship. Ac-cordingly, the symbols of these worship are often emerged in the decoration of the costume. The design of costume of the people in the northern areas of China is very simple. It is related with their monotheism. On the other hand, the costumes of twen쇼 minority races in the east-northern parts of China can be devided into three racial groups such as the long robes of Man people and Mongols, Tunics of the peoples in the west-northern areas, and the pants and jackets of Hoche people. The minorority races all has not only the unique costume habit but their costumes are also related with their living style and production means.

• 환경생물
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• 제36권1호
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• pp.33-42
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• 2018

인도네시아의 열대 이탄지는 황폐화되고 농경지 및 조림지로 전용되어왔다. 수로는 열대 이탄지의 지하수위를 관리하고 작물의 생산성을 높이기 위해 설치되었으나, 열대 이탄지의 구조를 파괴하고 침하 및 산불 발생 위험을 증가시켰다. 이에 따라, 인도네시아 정부는 수로로 인한 문제를 막기 위한 정책과 모라토리엄을 마련하였다. 그리고 해당 정책들에 따라 이탄지 재습지화에 관한 시범사업들이 일부 수행되었다. 우리나라가 열대 이탄지를 재습지화 한다면 추후 탄소 배출권을 확보할 수 있는 가능성이 있으므로, 적절한 재습지화에 관한 자료가 필요하다. 이에 따라, 본 연구에서는 열대 이탄지에 적용되는 정책의 흐름을 조사하고 이 시범사업들의 설치 계획, 고려사항, 댐 설계, 재료, 설치 방법, 모니터링 방법, 그리고 소요 시간 및 비용 등에 대해 분석하였다. 이탄층의 깊이가 3 m 이상인 지역은 개발이 제한되고 개발 허가 발급이 중단되었으며, 복원을 위한 수로차단이 설치되었다. 이 지역에서는 댐의 지속성과 지역 이해당사자들의 참여를 독려하는 것이 우선순위로 여겨졌다. 개발 허가지역의 경우에는 개벌과 화전이 금지되었으며, 지하수위를 유지하기 위한 수로차단에 목적을 두었고, 수로차단을 설치할 때에는 작업 및 비용의 효율성이 우선적으로 고려되었다. 조사 결과를 바탕으로 본 연구에서는 인도네시아 열대 이탄지의 규제 적용 및 수로차단 설치 시 적용할 수 있는 방안들을 제시하였다. 이러한 결과는 동남아시아 지역의 배수된 열대 이탄지에 적합한 수로차단을 계획하는 데 기여할 수 있을 것으로 사료된다.

• 지질공학
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• 제27권4호
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• pp.405-416
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• 2017

본 연구는 자유면대수층 즉, 충적대수층에서 필터층의 영향을 평가하기 위하여 수행하였다. 시험을 위해 모래층 및 자갈층으로 구성된 충적대수층에 필터층, 양수정, 관측정을 각각 설치한 모형시험장치를 제작하였다. 제작된 모형시험장치를 이용해 단계양수시험을 수행하였으며, 각 시험조별 투수특성을 확인하고 적정양수량 및 우물효율을 산정하였다. 모래층에서 단계별 양수량 분석을 통한 적정양수량 평가결과, 동일한 필터 두께를 가진 경우 이중필터는 22.03 L/min이며, 단일필터는 19.71 L/min로 단일필터에 비해 이중필터가 115.0% 양수량이 증대되는 것으로 평가되었다. 이중필터와 필터층 두께가 10 cm인 단일필터와 비교하면 이중필터에서 182.7%의 양수량 증대효과가 있는 것으로 분석되었다. 자갈층의 적정양수량 평가결과, 동일한 필터 두께를 가진 경우 이중필터는 73.56 L/min이며, 단일필터는 65.47 L/min로 단일필터에 비해 이중필터가 112.3% 양수량이 증대되는 것으로 평가되었다. 이중필터와 자갈층에서 필터층 두께가 10 cm인 단일필터를 비교하면 이중필터에서 160.9%의 양수량 증대효과가 있는 것으로 분석되었다. 모래층 우물효율을 분석한 결과 이중필터에서 최대 70.4%, 단일필터에서 최소 37.1%를 보이며, 자갈층에서는 필터재 두께가 30 cm인 이중필터와 단일필터에서 66.5%의 높은 우물효율을 보이나 필터재 두께가 10 cm인 단일필터에서는 22.5%로 낮게 평가되었다. 본 연구를 통해 필터재가 두꺼울수록 투수특성이 개선되는 것을 확인하였으며, 이중필터가 단일필터에 비해 양수량 및 우물효율이 상대적으로 높은 것으로 평가되었다. 이와 같은 결과는 우물설계에 실질적으로 활용이 가능할 것으로 판단된다.

• 한국안광학회지
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• 제8권2호
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• pp.111-117
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• 2003

국내외 썬글라스 반미러 코팅렌즈의 광학적 특성을 파악하기 위해, 분광광도계를 이용하여 반미러 코팅렌즈의 반사율을 측정하였으며, Macleod 프로그램을 이용해 계산한 결과와 비교 분석하였다. 또한 황금 색깔이 나는 TiN을 이용한 반미러 코팅렌즈를 설계하였고, 광학특성을 조사하였다. 반미러 코팅렌즈의 분석결과, 은색 투톤(two tone) 반미러 코팅은 금속 크롬(Cr)을 사용하였으며 경도를 증가시키기 위하여 크롬위에 $SiO_2$(또는 $Al_2O_3$)를 증착하여 사용하였다. 크롬 위에 증착되는 $SiO_2$의 두께는 10nm 정도가 적정한 것으로 판단된다. 칼라 반미러 코팅의 경우 디자인 결과는 각각 다음과 같다 ; blue 계열은 [air|$SiO_2$(66.3)|$TiO_2$(129.0)|$SiO_2$(62.9)|$SiO_2$(26.0)|$TiO_2$(120.3)|$SiO_2$(9.1)|glass]이며, gold 계열은 [air|$SiO_2$(60.6)|$TiO_2$(86.2)|$SiO_2$(13.5)|$TiO_2$(86.8)|$SiO_2$(214.38)|glass]이며, green 계열은 [air|$SiO_2$(74.3)|$TiO_2$(75.8)|$SiO_2$(44.3)|$TiO_2$(11.6)|$SiO_2$(160.8)|$TiO_2$(12.9)|$SiO_2$(183.3)|$TiO_2$(143.8)|glass]이며, silver 계열은 [air|$SiO_2$(21.2)|$TiO_2$(49.7)|$SiO_2$(149.3)|glass]이다. white 반미러 코팅인 경우는 [air|$SiO_2$(17nm)|$TiO_2$(43nm)(또는 $ZrO_2$)|$SiO_2$(87nm) polysiloxane($4.46{\mu}m$)|glass or CR-39]이며, 가시광선 영역(400~700 nm)에서 평균 19%의 반사율을 가지며 흡수가 적기 때문에 약 80%의 투과율을 보이는 white 타입의 반미러가 되게 된다. 황금빛 색깔을 띠는 반미러 코팅렌즈의 설계에 있어서 [air|$SiO_2$(170nm)|TiN(15nm)|glass]가 되면 CIE 좌표값은 거의 [air|Au(150nm)|glass]의 좌표값과 유사해지는 것을 볼 수 있었다.