• Plant Biotechnology Reports
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• 제2권3호
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• pp.207-212
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• 2008

Plantlets of Alocasia amazonica regenerated under a photon flux density (PFD) of 15 or $30{\mu}mol\;m^{-2}s^{-1}$ showed better growth and development than those grown under higher PFDs. While chlorophyll a and chlorophyll b decreased, the number of stomata increased with increasing PFD. Photoperiods also affected plantlet growth and stomatal development. Highest growth was observed for the short photoperiod (8/16 h) and for equinoctial (12/12 h) light and dark periods. Very few stomata developed in the leaves of plantlets grown under a short photoperiod (8/16 h) and the number of stomata increased with increasing light period. In conclusion, both light intensity and photoperiod independently affect growth of A. amazonica and development of stomata, depending on the intensity and duration of light treatment.

• Fisheries and Aquatic Sciences
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• 제8권1호
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• pp.27-33
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• 2005

This is a subsequent study to our previous finding that Pacific oysters, Crassostrea gigas, gained a so-called upper plateau concentration, around 30,000 ng/g dry weight digestive gland for benzo(a)pyrene, showed reproductive behavior but produced their ensuing reproductive outputs damaged. A serial dilution of sediment elutriates from Jinhae Bay, Korea, where pollution was progressive, were exposed to gametes of the Pacific oyster for 0, 5, 10, 20, 30, and 60 min to detail the pollutant effects on very young specimens. There was an apparent critical dilution over which adverse effects are evident. This was $10\%$ of the present sediment elutriate, corresponding to 0.3 ng/g on the basis of total polycyclic aromatic hydrocarbons (PAHs) for the oyster. Within the dilution the embryonic development was not influenced by the duration of exposure to its gamete stage. At higher dilutions over the critical dilution, occurrence of abnormality increased dependent on the pollutant dilution and the duration of exposure. Similar trends were also found in larval mortality. However, overall, the chemical toxicity was more significant to morphogenesis than to survival, suggesting a potential recruitment of the pollutants-induced abnormal larvae in the wild population to threaten the population integrity.

• 정보처리학회논문지D
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• 제17D권5호
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• pp.327-336
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• 2010

본 논문은 기능점수 소프트웨어 규모에 기반하여 개발노력과 일정과의 관계를 유도하는 소프트웨어 공식을 제안하였다. 기존의 소프트웨어 공식은 라인수에 기반을 두고 있다. 라인수는 개발언어에 따라 큰 차이를 보여 소프트웨어 규모 추정에 어려움이 많이 지적되고 있다. 먼저 라인수를 기능점수로 변환하는 방법을 고려하였다. 그러나 이 방법은 개발언어별로 라인수와 기능점수간 변환비율이 명확히 결정되지 않고 있고, 또한 특정 개발언어에 대해서는 변환비율이 제시되어 있지 않아 소프트웨어 공식을 유도하는데 실패하였다. 따라서 기능점수에 기반하여 개발된 대용량의 프로젝트 데이터를 대상으로 소프트웨어 공식을 직접 유도하였다. 첫 번째로 개발 프로젝트들 중에서 타당한 개발기간이 설정된 데이터들을 분류하였다. 두 번째로, 이 데이터에 대해 회귀분석을 통해 기능점수와 개발노력, 기능점수와 개발기간과의 관계를 유도하였다. 마지막으로 이들 관계로부터 소프트웨어 공식을 유도하였다. 제안된 모델은 라인수 기반의 모델이 갖고 있는 적용상 문제점들을 해결하여 실무에 쉽게 적용이 가능한 장점을 갖고 있다.

• Nuclear Engineering and Technology
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• 제45권3호
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• pp.393-400
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• 2013

Concrete undergoing early frost damage in cold weather will experience significant loss of not only strength, but also of permeability and durability. Accordingly, concrete codes like ACI-306R prescribe a minimum compressive strength and duration of curing to prevent frost damage at an early age and secure the quality of concrete. Such minimum compressive strength and duration of curing are mostly defined based on the strength development of concrete. However, concrete subjected to frost damage at early age may not show a consistent relationship between its strength and durability. Especially, since durability of concrete is of utmost importance in nuclear power plant structures, this relationship should be imperatively clarified. Therefore, this study verifies the feasibility of the minimum compressive strength specified in the codes like ACI-306R by evaluating the strength development and the durability preventing the frost damage of early age concrete for nuclear power plant. The results indicate that the value of 5 MPa specified by the concrete standards like ACI-306R as the minimum compressive strength to prevent the early frost damage is reasonable in terms of the strength development, but seems to be inappropriate in the viewpoint of the resistance to chloride ion penetration and freeze-thaw. Consequently, it is recommended to propose a minimum compressive strength preventing early frost damage in terms of not only the strength development, but also in terms of the durability to secure the quality of concrete for nuclear power plants in cold climates.

• 인간식물환경학회지
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• 제24권5호
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• pp.519-527
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• 2021

Background and objective: This study was conducted to establish a Plant Hardiness Zone (PHZ) map, investigate the effect of global warming on changes in PHZ, and elucidate the difference in the distribution of evergreen trees between the central and southern region within hardiness Zone 7b in Korea. Methods: Mean annual extreme minimum temperature (EMT) and related temperature fluctuation data for 40 years (1981 to 2020) in each of the meteorological observation points were extracted from the Open MET Data Portal of the Korea Meteorological Administration. Using EMT data from 60 meteorological observation points, PHZs were classified according to temperature range in the USDA Plant Hardiness Zone Map. Changes in PHZs for each decade related to the effects of global warming were analyzed. Temperature fluctuation before and after the day of EMT were analyzed for 4 areas of Seoul, Suwon, Suncheon, and Jinju falling under Zone 7b. For statistical analysis, descriptive statistics and ANOVA were performed using the IBM SPSS 22 Statistics software package. Results: Plant hardiness zones in Korea ranged from 6a to 9b. Over four decades, changes to warmer PHZ occurred in 10 areas, especially in colder ones. Based on the analysis of daily temperature fluctuation, the duration of sub-zero temperatures was at least 2 days in Seoul and Suwon, while daily maximum temperatures were above zero in Suncheon and Jinju before and after EMT day. Conclusion: It was found that the duration of sub-zero temperatures in a given area is an important factor affecting the distribution of evergreen trees in PHZ 7b.

• Journal of Nutrition and Health
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• 제26권1호
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• pp.34-46
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• 1993

This study was performed to investigate the interrelationship between fasting serum insulin, eating behaviour, daily energy intake and the fatness in obese and non-obese women. The possibility of fasting serum insulin as potential predictive factor for eating behaviour and daily energy intake was also investigated. The results are as follows: 1) In obese women ; Subjects with higher fasting serum insulin were associated with higher speed of eating and shorter meal duration time. No association could be found between daily energy intake or the degree of obesity and fasting serum insulin. There was a significant positive correlation between obesity, daily energy intake and speed of eating. Obesity, daily energy intake were negatively related to meal duration time. Subjects with a rapid speed of eating were apt to overeat during eating behaviour experiment. Our findings suggested that a rapid speed of eating is a contributing factor to the development of obesity in obese women. 2) In non-obese women ; While subjects with higher insulin level were apt to overeat, we could not find any relation between overeating and daily energy intake. There was no correlation between eating speed and daily energy intake, but a significant positive correlation was found between meal duration time and daily energy intake. The degree of fatness was increased with the lower daily energy expenditure per body weight, or the higher waist hip girth ratio, fasting serum insulin and daily energy intake.

• 대한족부족관절학회지
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• 제9권1호
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• pp.38-41
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• 2005

Purpose: To evaluate the drainage effect of silk suture following aspiration of the bursa as an early treatment of chronic lateral malleolar bursitis. Materials and Methods: Thirteen cases, which have over two weeks of history and over one year of follow-up, were investigated. The average duration of follow-up was 16.4 months. The average symptom duration before introduction into this study was 7.8 weeks. With an aseptic technique, the aspiration of the bursa was done with 18G needle and syringe and then the insertion of silk suture through the aspiration needle was performed. The amount of drainage was identified two or three times in a week and stitch out was done at the cessation of drainage. Over one year follow-up, recurrence, infection, pain, and limitation of range of motion were investigated by telephone interview. Results: Redness around the insertion site of silk suture was found in all cases, but there was no development of active infection or recurrence. The average duration of treatment is 10.4 days. Conclusion: The drainage with silk suture following aspiration of the bursa is less invasive and very effective method in the early treatment of chronic lateral malleolar bursitis.

• 한국음향학회지
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• 제31권2호
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• pp.63-72
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• 2012

본 연구는 다문화가정 베트남과 필리핀 이주여성의 발화속도와 쉼 특성에 대한 음향학적인 분석을 통하여 이주여성 대상 한국어교육 프로그램 개발의 기초자료를 제공하고자 하였다. 이주여성은 한국여성에 비해 느린 발화속도, 긴 쉼 지속시간과 높은 쉼 빈도를 나타냈다. 베트남집단보다 상대적으로 한국 거주기간이 긴 필리핀집단은 한국집단에 보다 가까운 특성을 보였다. 이주여성의 발화속도가 느리게 나타난 것은 조음속도가 느리고 거의 어절마다 쉼을 두고 읽는 습관에 기인한 것으로 보인다.

• 한국물환경학회지
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• 제29권1호
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• pp.55-65
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• 2013

It is very difficult to apply stream flow data directly to the management of Total Maximum Daily Loads because there are some differences between the unit watershed and the stream flow monitoring network in their characteristics such as monitoring locations and its intervals. Flow duration curve can be developed by linking the daily flow data of stream monitoring network to 8 day interval flow data of the unit watershed. This study investigated the current operating conditions of the stream flow monitoring network and the flow relationships between the unit watershed and the stream flow monitoring network. Criteria such as missing and zero value data, and correlation coefficients were applied to select the stream flow reference sites. The reference sites were selected in 112 areas out of 142 unit watersheds in 4 river basins, where the stream flow observations were carried out in relatively normal operating conditions. These reference sites could be utilized in various ways such as flow variation analysis, flow duration curve development and so on for the management of Total Maximum Daily Loads.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2007년도 학술발표회 논문집
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• pp.652-656
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• 2007

The major streams in South Korea have established the TMDL(Total Maximum Daily Loads) regulation for just 4 years. Traditional concepts in water quality management in South Korea are based upon the selection of a design streram flow which is 10-year averged flow exeedance probability 75%(Q275). That is, a single flow value based upon average long term flow conditions is chosen for application in dilution calculations, permit design, water quality modeling, etc. While these TMDLs seems to satisfy the requirement of the target water quality regulations, they have contributed little to any watershed/waterbody assessment and restoration plans. These types of TMDLs do little to characterize the problems the TMDLs are intended to address. For TMDLs to be more beneficial in the assessment and implementation process, TMDLs should reflect adequate water quality across flow conditions rather than at a single flow value such as average daily flow. In this paper, we developed LDC (load duration curve) methodology for theevaluation of Korean TMDL evaluation based on watershed scaled, physically based on SWAT(Soil and Water Assessment Tool) model.