• Title/Summary/Keyword: Period of use

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Estimation of Energy Use in Residential and Commercial Sectors Attributable to Future Climate Change (미래 기후변화에 따른 가정 및 상업 부문 에너지수요 변화 추정)

  • Jeong, Jee-Hoon;Kim, Joo-Hong;Kim, Baek-Min;Kim, Jae-Jin;Yoo, Jin-Ho;Oh, Jong-Ryul
    • Atmosphere
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    • v.24 no.4
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    • pp.515-522
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    • 2014
  • In this study it is attempted to estimate the possible change in energy use for residential and commercial sector in Korea under a future climate change senario. Based on the national energy use and observed temperature data during the period 1991~2010, the optimal base temperature for determining heating and cooling degree days (HDD and CDD) is calculated. Then, net changes in fossil fuel and electricity uses that are statistically linked with a temperature variation are quantified through regression analyses of HDD and CDD against the energy use. Finally, the future projection of energy use is estimated by applying the regression model and future temperature projections by the CMIP5 results under the RCP8.5 scenario. The results indicate that, overall, the net annual energy use will decrease mostly due to a large decrease in the fossil fuel use for heating. However, a clear seasonal contrast in energy use is anticipated in the electricity use; there will be an increase in a warm-season demand for cooling but a decrease in a cold-season demand for heating.

Individual Interests Tracking : Beyond Macro-level Issue Tracking (거시적 이슈 트래킹의 한계 극복을 위한 개인 관심 트래킹 방법론)

  • Liu, Chen;Kim, Namgyu
    • Journal of Information Technology Services
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    • v.13 no.4
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    • pp.275-287
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    • 2014
  • Recently, the volume of unstructured text data generated by various social media has been increasing rapidly; consequently, the use of text mining to support decision-making has also been growing. In particular, academia and industry are paying significant attention to topic analysis in order to discover the main issues from a large volume of text documents. Topic analysis can be regarded as static analysis because it analyzes a snapshot of the distribution of various issues. In contrast, some recent studies have attempted to perform dynamic issue tracking, which analyzes and traces issue trends during a predefined period. However, most traditional issue tracking methods have a common limitation : when a new period is included, topic analysis must be repeated for all the documents of the entire period, rather than being conducted only on the new documents of the added period. Additionally, traditional issue tracking methods do not concentrate on the transition of individuals' interests from certain issues to others, although the methods can illustrate macro-level issue trends. In this paper, we propose an individual interests tracking methodology to overcome the two limitations of traditional issue tracking methods. Our main goal is not to track macro-level issue trends but to analyze trends of individual interests flow. Further, our methodology has extensible characteristics because it analyzes only newly added documents when the period of analysis is extended. In this paper, we also analyze the results of applying our methodology to news articles and their access logs.

Design response spectra-compliant real and synthetic GMS for seismic analysis of seismically isolated nuclear reactor containment building

  • Ali, Ahmer;Abu-Hayah, Nadin;Kim, Dookie;Cho, Sung Gook
    • Nuclear Engineering and Technology
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    • v.49 no.4
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    • pp.825-837
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    • 2017
  • Due to the severe impacts of recent earthquakes, the use of seismic isolation is paramount for the safety of nuclear structures. The diversity observed in seismic events demands ongoing research to analyze the devastating attributes involved, and hence to enhance the sustainability of base-isolated nuclear power plants. This study reports the seismic performance of a seismically-isolated nuclear reactor containment building (NRCB) under strong short-period ground motions (SPGMs) and long-period ground motions (LPGMs). The United States Nuclear Regulatory Commission-based design response spectrum for the seismic design of nuclear power plants is stipulated as the reference spectrum for ground motion selection. Within the period range(s) of interest, the spectral matching of selected records with the target spectrum is ensured using the spectral-compatibility approach. NRC-compliant SPGMs and LPGMs from the mega-thrust Tohoku earthquake are used to obtain the structural response of the base-isolated NRCB. To account for the lack of earthquakes in low-to-moderate seismicity zones and the gap in the artificial synthesis of long-period records, wavelet-decomposition based autoregressive moving average modeling for artificial generation of real ground motions is performed. Based on analysis results from real and simulated SPGMs versus LPGMs, the performance of NRCBs is discussed with suggestions for future research and seismic provisions.

Transcript Analysis of Wheat WAS-2 Gene Family under High Temperature Stress during Ripening Period

  • Ko, Chan Seop;Kim, Jin-Baek;Hong, Min Jeong;Kim, Kyeong Hoon;Seo, Yong Weon
    • Plant Breeding and Biotechnology
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    • v.6 no.4
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    • pp.363-380
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    • 2018
  • Wheat is frequently exposed to high temperature during anthesis and ripening period, which resulted in yield loss and detrimental end-use-quality. The transcriptome analysis of wheat under high temperature stress during the early stage of the grain filling period was undertaken. Three expression patterns of differentially expressed genes (DEGs) during grain filling period were identified. The DEGs of seed storage protein and starch-branching enzyme showed continuous increases in their expressions during high temperature stress, as well as during the recovery period. The activities of the enzymes responsible for the elimination of antioxidants were significantly affected by exposure to high temperature stress. Only the WAS-2 family genes showed increased transcription levels under high temperature stress in dehulled spikelets. The relative transcription levels for sub-genome specific WAS-2 genes suggested that WAS-2 genes reacted with over-expression under high temperature stress and decreased back to normal expression during recovery. We propose the role of WAS-2 as a protective mechanism during the stage of grain development under high temperature in spikelets.

A Study on the Current Status and Characteristics of Reward Hanbok in Crowdfunding (크라우드 펀딩에 나타난 리워드 한복의 현황과 특성 연구)

  • Shim, Joonyoung
    • Journal of Fashion Business
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    • v.26 no.3
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    • pp.155-167
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    • 2022
  • Hanbok, a traditional Korean clothing, became a hip culture for young people in the late 2010s. As hanbok brands for young people appeared and distribution channels changed for them, hanbok appeared on the crowdfunding platform. This study summarized characteristics of hanbok provided as rewards by funding projects in Wadiz, the largest crowdfunding platform in Korea. Results of this study are as follows. First, since the first successful crowdfunding in 2015, it has shown rapidly growth. Second, as a result of examining the name of reward hanbok, 167 reward hanbok appeared. They could be divided into three periods: women's hanbok, unisex hanbok and trendy hanbok period. Third, looking at characteristics of reward hanbok from each period, feminine Chollic onepiece during the women's Hanbok period adopted the feminine interpretation of the original men's Hanbok. Characteristics of reward hanbok during the Unisex Hanbok period are in the direction of the closure. By adopting the direction of the closure of hanbok that both men and women can use, unisex hanbok is appeared. Finally, reward hanbok during the trendy hanbok period reflected trends such as genderless and hip. Hanbok reflected various trends from home culture to COVID-19 that occurred around the world at that time.

A Study on Wearing Test of Protective Clothing against a Toxic Substance (유해물질 차단을 위한 방호복의 착용실험에 관한 연구)

  • Chung, Myung-Hee;Park, Soon-Ja;Shin, Jung-Sook;Koshiba, Tomoko;Tamura, Teruko
    • Journal of the Korean Society of Clothing and Textiles
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    • v.30 no.11 s.158
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    • pp.1626-1635
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    • 2006
  • The purpose of this study was to search for comfortable protective clothing for waste incinerator workers. The experimental protective clothing came in two types: one whose outer side made use of polypropylene film, and the inner side, a non-woven rayon fabric processed with charcoal with a 10% density (CF): and one whose outer side made use of polyolefine and polyamide films, and the inner side, a non-woven polypropylene fabric (NNCF). Experiments were conducted on five healthy adult women whose average age was 21. These experiments were conducted at a climate chamber, in which the temperature and relative humidity were set below $28{\pm}1^{\circ}C\;and\;50{\pm}10%$, respectively. Measured were the rectal temperature, the skin temperature, the sweating rate, the weight loss, the heart rate, the blood pressure, the temperature, and the relative humidity of a microclimate and subjective sensation. These were measured within a period of 60 min, consisting of a 20-min stable period, a 20-min exercise period (walking exercise for 2 miles/hr on a treadmill), and a 20-min recovery period. Through this experiment, the differences between the human body's physiological reactions to CF and NNCF clothing, and the human body's comfort levels when wearing these, were determined.

Effect of Insamyangyoung-tang on the TEWL of High Dose Steroid Injected Hairless Mice (인참양영탕(人參養榮湯)이 장기간 고용량 스테로이드 투여 hairless mice의 피부장벽에 미치는 영향)

  • Nam, Hae-Jeong;Kim, Yoon-Bum
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.21 no.2
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    • pp.19-27
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    • 2008
  • Objective : The side effect of prolonged use of topical corticosteroids to skin is well-known. Moreover, resent studies have shown that prolonged use of systemic corticosteroids also negatively impacts skin barrier function. Corticosteroids have a major role in the practical management of many variable conditions. So, it is important to find the drug or the method which could protect the skin from the damage caused by corticosteroids. At former study, we investigated that Insamyangyoung-tang has some effect on skin barrier function of DNCB induced contact dermatitis hairless mice. So, this study was performed to research the effect of Insamyangyoung-tang on the TEWL with high dose steroid injected hairless mice. Method : Hairless mice were divided into 4 groups ; Control group, Group A, Group B and Group C. All groups were injected triamcinolone O.4mg for 10 times. Control group was medicated distilled water during the experimental period. Group A was medicated distilled water for 5 days before the $1^{st}$ injection day, and then medicated Insamyangyoung-tang extract during the experimental period. Group B was medicated Insamyangyoung-tang extract for 5 days before the $1^{st}$ injection day, and then medicated distilled water during the experimental period. Group C was medicated Insamyangyoung-tang extract for 5 days before the $1^{st}$ injection day, and then medicated Insamyangyoung-tang extract during the experimental period. TEWL of each group was measured for 5 times. After the $10^{th}$ injection, the tissue sample was made and the damage of epithelial cell was examined. Statistical significance was set at p<0.05 by using non parametric methods and repeated-anova.. Results : Group C showed significant effect on TEWL change of hairless mice evoked by triamcinolone injection. Group A and Group B also showed some effect, but there was no statistical significance.

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Effects of Rituximab Including Long-term Maintenance Therapy in Children with Nephrotic Syndrome in a Single Center of Korea

  • Kim, Seong Heon;Lim, Taek Jin;Song, Ji Yeon;Kim, Su Young
    • Childhood Kidney Diseases
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    • v.22 no.1
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    • pp.1-6
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    • 2018
  • Rituximab (RTX) is a chimeric monoclonal antibody that inhibits CD20-mediated B-cell proliferation and differentiation. Several studies have examined its use in intractable nephrotic syndrome (NS) with some positive results. However, those studies examined such effects for a short-term period of 1 year, and some patients continued to relapse after a lapse in RTX treatment. Our use of RTX as a maintenance therapy (RTX injection when the CD19 cell count exceeded $100-200/{\mu}L$ before relapse) showed some noticeable efficacy. We used RTX in 19 patients with steroid-dependent NS (SDNS). In 12 patients treated with RTX maintenance therapy, only one relapse occurred. The mean treatment period was $23.4{\pm}12.7months$, and the mean number of RTX administrations was $3.9{\pm}1.6$. The relapse rates were decreased (from 2.68/year to 0.04/year), and the drug-free period also increased (from 22.5 days/year to 357.1 days/year) during maintenance therapy. The other seven patients were treated with one cycle of RTX or additional cycles in case of relapse (non-maintenance therapy). Relapse rates were significantly decreased after RTX treatment (from 1.76/year to 0.96/year, P=0.017). The relapse-free period was $15.55{\pm}7.38$ (range, 5.3-30.7) months. No severe side effects of RTX were found except for a hypersensitivity reaction such as fever and chills during its infusion. In conclusion, RTX is considered an effective and safe option to reduce the relapse rate by a single- or maintenance-interval therapy in SDNS.

Information Asymmetry and Financing Behavior of the Korean Firms (정보비대칭과 기업의 자본조달)

  • Guahk, Se-Young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.9
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    • pp.3827-3833
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    • 2011
  • This paper performed empirical tests of the validity of the pecking order theory which explains financing behavior of firms under information asymmetry. The results of regression analyses using the data of listed manufacturing companies in the Korean Stock Market from 1981 to 2010 have shown strong evidences supporting the pecking order theory. Especially regression coefficients of change of debt on funds deficit and control variables were found to be almost (+1) with statistically significance, which is interpreted as being consistent with the pecking order theory. Same results were found when I performed regression analyses by dividing the sample period into pre-currency crisis period, currency crisis period and post-currency crisis period and using 2 regression models. Change of tangible asset were found to function as collateral rather than reducing information asymmetry and as the firm size decreased, use of debt increased and as profitability increased use of debt decreased, which are consistent with the pecking order theory.

Is it suitable to Use Rainfall Runoff Model with Observed Data for Climate Change Impact Assessment? (관측자료로 추정한 강우유출모형을 기후변화 영향평가에 그대로 활용하여도 되는가?)

  • Poudel, Niroj;Kim, Young-Oh;Kim, Cho-Rong
    • Proceedings of the Korea Water Resources Association Conference
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    • 2011.05a
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    • pp.252-252
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    • 2011
  • Rainfall-runoff models are calibrated and validated by using a same data set such as observations. The past climate change effects the present rainfall pattern and also will effect on the future. To predict rainfall-runoff more preciously we have to consider the climate change pattern in the past, present and the future time. Thus, in this study, the climate change represents changes in mean precipitation and standard deviation in different patterns. In some river basins, there is no enough length of data for the analysis. Therefore, we have to generate the synthetic data using proper distribution for calculation of precipitation based on the observed data. In this study, Kajiyama model is used to analyze the runoff in the dry and the wet period, separately. Mean and standard deviation are used for generating precipitation from the gamma distribution. Twenty hypothetical scenarios are considered to show the climate change conditions. The mean precipitation are changed by -20%, -10%, 0%, +10% and +20% for the data generation with keeping the standard deviation constant in the wet and the dry period respectively. Similarly, the standard deviations of precipitation are changed by -20%, -10%, 0%, +10% and +20% keeping the mean value of precipitation constant for the wet and the dry period sequentially. In the wet period, when the standard deviation value varies then the mean NSE ratio is more fluctuate rather than the dry period. On the other hand, the mean NSE ratio in some extent is more fluctuate in the wet period and sometimes in the dry period, if the mean value of precipitation varies while keeping the standard deviation constant.

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