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Reconstruction of Post-Glacial Environmental Changes in Yeongjong-do Island Based on Palynological Evidences (화분분석에 기초한 후빙기 영종도의 환경변화)

  • PARK, Ji-hoon;PARK, Kyeong
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.2
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    • pp.173-185
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    • 2012
  • Authors performed pollen analysis in deposits at a coastal plain at Yeongjong-do Island located in Incheon, South Korea. Sampling site (7.2 m a.s.l.) belongs to the cool temperate deciduous broad-leaf forest. Environmental changes since 8,900 yrs B.P. reconstructed from pollen analysis are as follows; JS-I stage (c.a. 8,900~8,500 yrs B.P. ) was cool temperate northern mixed-forest which is comparable to the early PostGlacial pollen stage RI in Japan, in which Pinus and Quercus were dominant and Abies and Picea were also found. At that time, climate was relatively cooler and dryer than today. JS-II stage (sometime between 8,500~4,000 yrs B.P.) was Pinus-dominant coniferous forest, which is comparable to the mid-Post-Glacial pollen stage RII. Mixed forest of Pinus, Quercus and Carpinus was dominant in JS-III stage (c.a. 4,000 yrs B.P). We assumed that JS-II and JS-III stage were relatively warmer and more humid than JS-I stage, and were more like present conditions. JS-IV stage (sometime between 4,000~900 yrs B.P.) was Pinus-dominant coniferous forest which is comparable to the late Post-Glacial pollen stage RIII. JS-V stage (c.a. 900 yrs B.P. ~present) was second growth Pinus-dominant coniferous forest stage. During the last stage, non-arboreal pollen was more common than arboreal pollen and Fagopyrum appeared among the herbaceous plant, which indicates that it is comparable to the RIIIb stage which was the age of human interference. From the JS-V stage, humans in the study site started agricultural activities.

A Study on Spatial Downscaling of Satellite-based Soil Moisture Data (토양수분 위성자료의 공간상세화에 관한 연구)

  • Shin, Dae Yun;Lee, Yang Won;Park, Mun Sung
    • Proceedings of the Korea Water Resources Association Conference
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    • 2017.05a
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    • pp.414-414
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    • 2017
  • 토양수분은 지면환경에서 일어나는 수문 및 에너지 순환을 이해하는 데 있어 중요한 기상인자이다. 토양수분 현장관측은 땅속에 매설된 센서에 의해 상당히 정확하게 이루어지만, 관측점 수가 충분치 않아 공간적 연속성을 확보하지 못하는 어려움이 존재한다. 이에 광역적 및 연속적 관측이 가능한 마이크로파 위성센서가 토양수분 정보 획득을 위한 보조수단으로서 그 중요성이 부각되고 있다. 마이크로파 위성센서는 구름 등 기상조건의 제약을 받지 않으며, 1978년 이래 현재까지 여러 위성에 의해 25 km 및 10 km 해상도의 전지구 토양수분자료가 생산되어 왔다. 마이크로파 센서를 이용한 토양수분자료는 동일지점에 대하여 하루 2회 정도 산출되므로 적절한 시간분해능을 가지지만, 공간해상도가 최고 10 km로서 지역규모의 수문분석에 적용하기에는 충분치 않다. 이러한 토양수분자료의 공간해상도 문제 해결을 위하여 다양한 지면환경요소를 활용한 통계적 다운스케일링이 대안으로 제시되었다. 최근의 선행연구들은 대부분 방정식을 이용한 결합모형을 통해 통계적 다운스케일링을 수행하였는데, 회귀식과 같은 선형결합뿐 아니라 신경망이나 기계학습 등의 비선형결합에서도, 불가피하게 발생할 수밖에 없는 잔차(residual)로 인하여 다운스케일링 전후의 공간분포 패턴이 달라져버리는 문제를 안고 있었다. 회귀분석에 잔차의 공간내삽을 결합시킨 회귀크리깅(regression kriging)은 잔차보정을 통해 이러한 문제를 해결함으로써 다운스케일링 전후의 공간분포 일관성을 보장하는 기법이다. 이 연구에서는 회귀크리깅을 이용하여 일자별 AMSR2(Advanced Microwave Scanning Radiometer 2) 토양수분 자료를 10 km에서 1 km 해상도로 다운스케일링하고, 다운스케일링 전후의 자료패턴 일관성을 평가한다. 지면온도(LST), 지면온도상승률(RR), 식생온도건조지수(TVDI)는 일자별로 DB를 구축하였고, 식생지수(NDVI), 수분지수(NDWI), 지면알베도(SA)는 8일 간격으로 DB를 구축하였다. 이러한 8일 간격의 자료를 일자별로 변환하기 위하여 큐빅스플라인(cubic spline)을 이용하여 시계열내삽을 수행하였다. 또한 상이한 공간해상도의 자료는 최근린법을 이용하여 다운스케일링 목표해상도인 1 km에 맞도록 변환하였다. 우선 저해상도 스케일에서 추정치를 산출하기 위해서는 저해상도 픽셀별로 이에 해당하는 복수의 고해상도 픽셀을 평균화하여 대응시켜야 하며, 이를 통해 6개의 설명변수(LST, RR, TVDI, NDVI, NDWI, SA)와 AMSR2 토양수분을 반응변수로 하는 다중회귀식을 도출하였다. 이식을 고해상도 스케일의 설명변수들에 적용하면 고해상도 토양수분 추정치가 산출되는데, 이때 추정치와 원자료의 차이에 해당하는 잔차에 대한 보정이 필요하다. 저해상도 스케일로 존재하는 잔차를 크리깅 공간내삽을 통해 고해상도로 변환한 후 이를 고해상도 추정치에 부가해주는 방식으로 잔차보정이 이루어짐으로써, 다운스케일링 전후의 자료패턴 일관성이 유지되는(r>0.95) 공간상세화된 토양수분 자료를 생산할 수 있다.

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A Study on the Characteristics of Garden Architecture in Italian Renaissance Villa Lante (이탈리아 르네상스 빌라 란테의 정원건축적 특성)

  • Choi, Jong-Hee
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.29 no.2
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    • pp.90-98
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    • 2011
  • This study aims to discuss the characteristics of garden architecture in Italian Renaissance Villa Lante that was constructed by the cardinal in Bagnaia at 16th century through actual survey and analysis of the garden's elements. To do this, it was studied in two ways: Analysis of the present conditions and review historical documents. The results are as follows. First, the buildings, the gardens and the surrounding landscapes are visually connected each other in relations between the topography and the surrounding landscapes. Second, the spatial composition accepted Neoplatonic law of multiple proportions and was influenced by ancient myth and "Liber ruralium commodorum" of Pietro de Crescenzi(1305). Third, the garden's elements consist of plants, buildings and items. In plants, the upper plants are fir tree, cypress and pine tree and the lower plants are english holly, box tree and sweet oleander. The buildings are casino, loggia and terrace. The items are pot, sundial, chair, viewing platform and fountain. The result of this study, the political and social, technical phenomena which constitute construction pattern affected the locational property and the spatial organization of the neighbor on Villa Lante.

A study on frost prediction model using machine learning (머신러닝을 사용한 서리 예측 연구)

  • Kim, Hyojeoung;Kim, Sahm
    • The Korean Journal of Applied Statistics
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    • v.35 no.4
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    • pp.543-552
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    • 2022
  • When frost occurs, crops are directly damaged. When crops come into contact with low temperatures, tissues freeze, which hardens and destroys the cell membranes or chloroplasts, or dry cells to death. In July 2020, a sudden sub-zero weather and frost hit the Minas Gerais state of Brazil, the world's largest coffee producer, damaging about 30% of local coffee trees. As a result, coffee prices have risen significantly due to the damage, and farmers with severe damage can produce coffee only after three years for crops to recover, which is expected to cause long-term damage. In this paper, we tried to predict frost using frost generation data and weather observation data provided by the Korea Meteorological Administration to prevent severe frost. A model was constructed by reflecting weather factors such as wind speed, temperature, humidity, precipitation, and cloudiness. Using XGB(eXtreme Gradient Boosting), SVM(Support Vector Machine), Random Forest, and MLP(Multi Layer perceptron) models, various hyper parameters were applied as training data to select the best model for each model. Finally, the results were evaluated as accuracy(acc) and CSI(Critical Success Index) in test data. XGB was the best model compared to other models with 90.4% ac and 64.4% CSI, followed by SVM with 89.7% ac and 61.2% CSI. Random Forest and MLP showed similar performance with about 89% ac and about 60% CSI.

Structural and Photocatalytic Properties of TiO2 Thin Film Coated Glass Beads (유리알에 코팅된 TiO2 박막의 구조 및 광촉매 특성)

  • Ji Eun, Jeong;Chang-Yong, Lee
    • Applied Chemistry for Engineering
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    • v.34 no.1
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    • pp.30-35
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    • 2023
  • The glass bead surface was coated using a TiO2 sol, after which dry-treated (TB) and calcined (TBc) samples were prepared. Photocatalytic degradation of methylene blue and toluene, as well as characterization of the TiO2 thin films, were carried out. The TiO2 thin film of the TB sample had the same shape as the sponge foam, according to FE-SEM, XPS, and FTIR analyses, and contained both amorphous and crystalline TiO2. On the other hand, crystalline TiO2 was mainly present in the TiO2 thin film of the TBc sample, and needle-shaped particles and tiny ones were mixed. The adsorption capacity for methylene blue and the degradation rate of the TBc sample were less than 10 % compared with those of the TB sample, and the adsorption capacity and degradation rate of the TBc sample decreased similarly as the amount of TiO2 coating increased. The amount of toluene adsorption for the TBc sample (46 mg/g) was smaller than that of the TB sample with the same coating amount, but the degradation rate was similar. In the case of the TB sample, the degradation rate for toluene decreased less than the adsorption capacity as the amount of TiO2 coating increased. This result is considered to be because, in the non-calcined TB sample, the active site reduction of the crystalline particles occurred less and the specific surface area of the amorphous texture decreased as the amount of TiO2 coating increased.

A Study on the Physical Characteristics of Grout Material for Backfilling Ground Heat Exchanger (지중 열교환기용 뒤채움재의 물리적 특성 연구)

  • Choi, Hang-Seok;Lee, Chul-Ho;Choi, Hyo-Pum;Woo, Sang-Baik
    • Journal of the Korean Geotechnical Society
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    • v.24 no.1
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    • pp.37-49
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    • 2008
  • A geothermal heat pump system is a preferable alternative energy system in Korea because it uses the heat energy of the earth, which is environmentally friendly and inexhaustible. In order to characterize the thermal conductivity and viscosity of grout materials used for backfilling ground heat exchangers, nine bentonite grouts, one marine clay from Boryung, and cement grouts adapted in the United State have been considered in this study. The bentonite grouts indicate that the thermal conductivity and viscosity increase with the content of bentonite or filler (silica sand). In addition, material segregation can be observed when the viscosity of grout is relatively low. The marine clay turns out to be unsuitable for backfilling the ground heat exchanger due to its insufficient swelling potential. The saturated cement grouts appear to possess much higher thermal conductivity than the saturated bentonite grouts, and the reduction of thermal conductivity in the cement grouts after drying specimens is less than that in the case of the bentonite grouts. Maintaining the moisture content of grouts is a crucial factor in enhancing the efficiency of ground heat exchangers.

Investigation on a Way to Maximize the Productivity in Poultry Industry (양계산업에 있어서 생산성 향상방안에 대한 조사 연구)

  • 오세정
    • Korean Journal of Poultry Science
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    • v.16 no.2
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    • pp.105-127
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    • 1989
  • Although poultry industry in Japan has been much developed in recent years, it still needs to be developed , compared with developed countries. Since the poultry market in Korea is expected to be opened in the near future it is necessary to maximize the Productivity to reduce the production costs and to develop the scientific, technologies and management organization systems for the improvement of the quality in poultry production. Followings ale the summary of poultry industry in Japan. 1. Poultry industry in Japan is almost specized and commercialized and its management system is : integrated, cooperative and developed to industrialized intensive style. Therefore, they have competitive power in the international poultry markets. 2. Average egg weight is 48-50g per day (Max. 54g) and feed requirement is 2. 1-2. 3. 3. The management organization system is specialized and farmers in small scale form complex and farmers in large scale are integrated.

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Active Inferential Processing During Comprehension in Poor Readers (미숙 독자들에 있어 이해 도중의 능동적 추리의 처리)

  • Zoh Myeong-Han;Ahn Jeung-Chan
    • Korean Journal of Cognitive Science
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    • v.17 no.2
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    • pp.75-102
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    • 2006
  • Three experiments were conducted using a verification task to examine good and poor readers' generation of causal inferences(with because sentences) and contrastive inferences(with although sentences). The unfamiliar, critical verification statement was either explicitly mentioned or was implied. In Experiment 1, both good and poor readers responded accurately to the critical statement, suggesting that both groups had the linguistic knowledge necessary to the required inferences. Differences were found, however, in the groups' verification latencies. Poor, but not good, readers responded faster to explicit than to implicit verification statements for both because and although sentences. In Experiment 2, poor readers were induced to generate causal inferences for the because experimental sentences by including fillers that were apparently counterfactual unless a causal inference was made. In Experiment 3, poor readers were induced to generate contrastive inferences for the although sentences by including fillers that could only be resolved by making a contrastive inference. Verification latencies for the critical statements showed that poor readers made causal inferences in Experiment 2 and contrastive inferences in Experiment 3 doting comprehension. These results were discussed in terms of context effect: Specific encoding operations performed on anomaly backgrounded in another passage would form part of the context that guides the ongoing activity in processing potentially relevant subsequent text.

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Weight Reduction Dieting Survey and Satisfaction Degree and Diet Related Knowledge among Adult Women by Age (연령별 성인 여성의 체중감량 다이어트 실태와 만족도 및 관련지식)

  • Kim, Myung-Kyung;Lee, Gui-Chu
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.5
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    • pp.572-582
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    • 2006
  • This survey was conducted from June 2004 to August 2004, through questionnaires given to 432 women aged ranging from 20 to 50 years, who were living in the Seoul metropolitan area. The questionnaires were designed to determine the physique, level of obesity and dieting survey as well as to uncover which diets were in fashion and their satisfaction degree. Dieting-related knowledge and dieting side effects were also investigated. The results were as follows: In dieting survey, as the age increased, dieting for health reason (52.3%) increased, whereas that for aesthetic reasons (32.6%) decreased (p<0.05). The most effective methods of dieting were exercise (50.2%) and diet (45.0%) regimens. In regards to exercise frequency, 46.5% for none, 23.5% for 1-2 times a week, suggesting that most respondents do not practice exercise for dieting purposes (p<0.05). Major source for dieting was shown to be obtained from relative family or friends (31.7%), newspapers or magazines (29.3%) and internet (14.9%). As the age decreased, information from the latter increased, whereas that from TV program (21.2%) decreased (p<0.05). Reasons for excess weight were bad eating habits (39.6%), lack of exercise (38.3%), pregnancy and childbirth (10.6%). In fad dieting, while organic foods and aerobic exercises scored the highest satisfaction degree among diet and exercise regimens, on the other hand, sauna, steam baths and high temperature half-immersion baths scored the highest among surgery and other special therapies. As the age increased, the satisfaction degree for organic foods such as organic vegetable and high functional boiled cooked rice increased (p<0.05). As the age increased, scores on dieting-related knowledge decreased. Side effects of dieting included dizziness 06.2%) fatigue (15.1%) indigestion/constipation (11.1%) physical weakness 00.5%), loss of concentration (7.8%), dry skin (7.4%) loss of motivation (6.7%). The above results showed that attitude toward dieting among adult women varied with age and in light of the well-being trend, organic foods and aerobic exercises scored the highest satisfaction degree through all age.

Quality Characteristics of Takju Fermentation by Addition of Chestnut Peel Powder (율피가루를 첨가한 탁주의 품질 특성)

  • Jeong Jin-Woong;Park Kee-Jai;Kim Myung-Ho;Kim Dong-Soo
    • Food Science and Preservation
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    • v.13 no.3
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    • pp.329-336
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    • 2006
  • The characteristics of mash qualities of takju prepared by addition of chestnut peel powder(5%, 10%, 20% and 30% per steamed rice) were investigated during fermentation. That is, in all fermentation periods, changes of pit total acid, organic acids, solids, amino nitrogen, total sugar and reducing sugar, microorganisms, alcohol and color were determined and analyzed. There was significant differences in characteristics of mash qualities by addition of chestnut peel powder. In general, contents of total acid, organic acids, amino nitrogen, total sugar, reducing sugar and ethanol of takju added with chestnut peel powder were lower than those of steamed rice only, whereas solid contents was higher. But ethanol content of takju added with 5% of chestnut peel powder after 8 days of fermentation was 9.6% which was similar to that of takju prepared by addition of steamed lice only. Also, microbial populations such as total viable cells, yeast and lactic acid bacteria of the treatments were increased to about $10^8CFU/mL$ after 2 days of fermentation and then decreased gradually. In the beginning stage of fermentation color differences value of the treatments were $1.99{\sim}10.27$, and the differentials reduced gradually during fermentation.