• Asian-Australasian Journal of Animal Sciences
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• 제3권3호
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• pp.231-242
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• 1990

A study is reported which investigated the additive nature of digestible energy (DE) from dietary nutrients and to estimate the relative energy values of different energy-yielding nutrients in practical trout diets. A growth study was conducted over 12 weeks with 6 diets. Rainbow trout (Oncorhynchus mykiss) were fed diets once a day ad libitum. Digestible energy values determined and calculated had direct relationship indicating additive nature of such values for feed ingredients. Overall growth performance was best in a diet containing 33% digestible protein (DP) with a DP/DE ratio of 18.6. A reduction in digestible protein level with the same DP/DE rat io led to a significant decrease in growth and feed efficiency. The increase of 7% of lipid with concomitant decrease in protein resulted in the relative gain of 130% in growth and nutrient retention, suggesting that 1 g of lipid is equal to about 1.3 g of proteins in terms of net energetic value. Replacement of 10% of dietary lipid by carbohydrates led to a slight decrease in energy retention efficiency but to a great increase in lipid retention efficiency (130%) showing that dietary carbohydrates led to increased lipogenesis.

• Safety and Health at Work
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• 제13권1호
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• pp.104-111
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• 2022

Background: The IMPPAC cohort (Implications of the COVID-19 pandemic on psychosocial aspects and work ability among Brazilian workers) seeks to understand the impact of the pandemic on Brazilian workers. This article describes the occupational profile, psychosocial aspects, and work ability determined during the baseline and follow-up measurements of the cohort. Methods: Workers were invited to participate through media advertisements, social networks, and emails. From June to September 2020, 1211 workers were included in the cohort. Follow-up measurements finished on October 2021 with 633 workers. Data were collected through standardized questionnaires using Google Forms. Psychosocial aspects were assessed using the COPSOQ II-Br. Work ability was assessed using the Work Ability Index (WAI). Results: At baseline and follow-up, high proportion of workers were in the risk zone with regard to work pace, emotional work demands, influence on work, work-family conflict, burnout, and stress. Approximately 75% of the workers reported good to excellent work ability at baseline and follow-up. Conclusion: The occupational profile, psychosocial aspects, and work ability of Brazilian workers from the IMPPAC cohort were described. Psychosocial aspects and WAI were similar at baseline and follow-up.

• 대한소아치과학회지
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• 제33권3호
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• pp.365-376
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• 2006

할로겐, 플라즈마 그리고 2세대 고강도 LED 광중합기를 이용하여 치면열구전색제를 중합하는 과정에서 산소 차단 용액인 glycerin gel($DeOx^{(R)}$)의 도포, 질소가스와 탄산가스를 분사시켜 공기 중 산소와의 접촉을 차단시킨 후 산소억제층의 두께, 치면열구전색제의 중합률 그리고 표면경도를 측정, 평가하였다. 각각의 제작된 시편을 HPLC에서 역상크로마토그래피를 이용하여 미반응 모노머 TEGDMA의 용출양을 측정하여 중합률을 평가하였고, Vickers hardness tester를 이용하여 표면미세경도를 측정, 광학현미경을 이용하여 산소억제층의 두께를 측정하여 다음과 같은 결과를 얻었다. 1. 질소 및 탄산가스를 분사하면서 중합한 군, $DeOx^{(R)}$를 도포한 후 중합한 군 모두 공기 중에서 중합한 군보다. TEGDMA 용출량이 감소되었다(p<0.05). 2. 할로겐 광으로 20초간 중합한 경우 $DeOx^{(R)}$를 도포한 군과 질소 및 탄산가스를 분사한 군의 TEGDMA 용출량은 유사하였지만(p>0.05), 40초로 중합한 경우 탄산가스 분사군이 질소가스 분사군보다 TEGDMA 용출량이 적었다(p<0.05). 3. 플라즈마 광으로 10초간 중합한 경우 $DeOx^{(R)}$를 도포한 군의 TEGDMA 용출량이 가장 적었고(p<0.05), 탄산가스 분사군이 질소가스 분사군보다 용출량이 적었다(p<0.05). 4. LED 광원에서는 탄산가스 분사군이 질소가스 분사군보다 TEGDMA의 용출량이 적었다(p>0.05). 5. 세 광원 공히 공기 중에서 중합한 군보다 산소를 차단한 상태에서 중합한 군에서 미세경도가 크게 나타났다(p<0.05). 6. $DeOx^{(R)}$로 처리했을 때 플라즈마 광 10초와 LED광 20초 중합군이 할로겐 광 40초 중합군보다 미세경도 값이 높았고, 질소가스와 탄산가스 분사하에서 플라즈마 광으로 10초간 중합한 경우와 LED 광으로 20초간 중합 한 경우가 할로겐 광으로 40초간 중합한 경우 보다 높은 미세경도 값을 보였다(p<0.05). 7. 세 광원 모두 공기 중에서 중합한 군에 비해 질소 및 탄산가스 분사를 분사하면서 중합한 군 $DeOx^{(R)}$를 도포한 후 중합한 군이 산소억제층의 두께가 평균 49%의 감소되었으며(p<0.05), 이들 산소를 차단한 군 간의 유의차는 없었다.

• Nuclear Engineering and Technology
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• 제47권1호
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• pp.26-32
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• 2015

During the course of a severe accident in a light water nuclear reactor, large amounts of hydrogen can be generated and released into the containment during reactor core degradation. Additional burnable gases [hydrogen ($H_2$) and carbon monoxide (CO)] may be released into the containment in the corium/concrete interaction. This could subsequently raise a combustion hazard. As the Fukushima accidents revealed, hydrogen combustion can cause high pressure spikes that could challenge the reactor buildings and lead to failure of the surrounding buildings. To prevent the gas explosion hazard, most mitigation strategies adopted by European countries are based on the implementation of passive autocatalytic recombiners (PARs). Studies of representative accident sequences indicate that, despite the installation of PARs, it is difficult to prevent at all times and locations, the formation of a combustible mixture that potentially leads to local flame acceleration. Complementary research and development (R&D) projects were recently launched to understand better the phenomena associated with the combustion hazard and to address the issues highlighted after the Fukushima Daiichi events such as explosion hazard in the venting system and the potential flammable mixture migration into spaces beyond the primary containment. The expected results will be used to improve the modeling tools and methodology for hydrogen risk assessment and severe accident management guidelines. The present paper aims to present the methodology adopted by Institut de Radioprotection et de $S{\hat{u}}ret{\acute{e}}$ $Nucl{\acute{e}}aire$ to assess hydrogen risk in nuclear power plants, in particular French nuclear power plants, the open issues, and the ongoing R&D programs related to hydrogen distribution, mitigation, and combustion.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2005년도 제31회 KOSCO SYMPOSIUM 논문집
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• pp.93-96
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• 2005

High temperature furnace such as Steam power plant and incinerator contribute considerable part of NOx generation and face urgent demand of De-NOx system. Reducing agents are necessary to use De-NOx system. In this study mixing caused by direct injection of reducing agent solution spray into flue gas duct was measured. Carbonated water was used as tracer and simulated agent because ammonia as a reducing agent is not proper to experiment. Mixing and evaporation must occur simultaneously and quickly enough to achieve desirable efficiency. To achieve that, the angle of attack of static mixer and the location is simulated and $CO_2$ concentration is measured.

• IEIE Transactions on Smart Processing and Computing
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• 제5권2호
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• pp.77-84
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• 2016

In the field of natural language processing, Universal Networking Language (UNL) has been used by various researchers as an inter-lingual approach to automatic machine translation. The UNL system consists of two main components, namely, EnConverter for converting text from a source language to UNL, and DeConverter for converting from UNL to a target language. Currently, many projects are researching how to apply UNL to different languages. In this paper, we introduce the tools that are UNL's applications and discuss how to reuse them to encode a Vietnamese sentence into UNL expressions and decode UNL expressions into a Vietnamese sentence. The testing was done with about 1,000 Vietnamese sentences (a dictionary that includes 4573 entries and 3161 rules). In addition, we compare the proportion of sentences translated based on a direct method (Google Translator) and another one based on UNL.

• Bulletin of the Korean Chemical Society
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• 제28권4호
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• pp.589-595
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• 2007

The conversion of both the racemic and resolved forms of the Co(III) complex of an hydroxymethyl-substituted tripodal hexamine to macrobicycles via reaction with formaldehyde and nitromethane (and subsequent reduction of the product) has been conducted. The prospect is that it will provide cage complexes in which the hydroxyl substituent is sufficiently remote from the metal ion centre for its nucelophilicity to be largely unaffected. X-ray structure determinations have been used to characterise these new cage species as well as some complexes of the precursor hexamine and its mono-aminal. The electrochemistry and optical activity of the complexes have also been studied in detail.

• 천문학회보
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• 제44권1호
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• pp.41.3-41.3
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• 2019

Ices in interstellar environments are well traced mostly by their absorption features in the near- to mid-infrared spectrum. The infrared camera (IRC) aboard AKARI provides us the near-infrared spectroscopic data which cover $2.5-5.0{\mu}m$ with a spectral resolution of R ~ 120. Our AKARI spectroscopic survey of young stellar objects (YSOs), including low-luminosity protostars and background stars, revealed the absorption features of $H_2O$, $CO_2$, CO, and XCN ice components. We present near-infrared spectra of the observed targets and compare their ice abundances with those previously derived from various YSOs and the background stars behind dense molecular clouds and cores. In addition, we suggest possible science cases for SPHEREx, NASA's new near-infrared space observatory, based on the results from our AKARI IRC spectroscopic study.

• 한국산학기술학회논문지
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• 제19권9호
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• pp.518-525
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• 2018

21세기에 들어서면서 기후변화로 인한 환경변화가 심각해짐에 따라 온실가스 배출에 대한 관심도 높아지고 있다. 우리나라의 기온은 1904년 이후 2000년까지 약 $1.5^{\circ}C$ 상승하였으며, 기후가 아열대 특성을 나타내는 것으로 조사되었다. 이에 따라 홍수 및 가뭄 등의 발생횟수가 증가하여 인간이 활용할 수 있는 용수가 매년 감소하고 있으며, 상수도 사용에 대한 비용은 매년 상승하고 있어 평소 버려지는 폐수의 재이용은 불가피한 상황에 직면해 있다. 본 연구는 반도체 공정에 투입되는 초순수 제조과정에서 발생되는 농축폐수를 재이용시스템을 설치하여 6개월간 운전한 월별 자료를 활용하여 온실가스 발생량 및 절감방안 등에 대하여 조사하였다. 조사결과 상수도 공급량은 월 평균 약 $2,767m^3$의 절감 효과가 있음을 알 수 있었다. 온실가스 발생량은 물재이용시스템의 전기사용량으로 인해 월 평균 약 $1,329.07kg-CO_2$ 추가발생 하였지만, 상수도 사용량 절감에 따른 월 평균 $918.64kg-CO_2$ 감축량을 반영하면, 월 평균 $410.43kg-CO_2$의 온실가스가 증가됨을 알 수 있었다. 물재이용시스템의 일부 공정을 개선한다면 온실가스 발생량은 증가가 아닌 월 평균 $254.41kg-CO_2$로 절감됨을 확인할 수 있었다.

• 한국식품과학회지
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• 제29권2호
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• pp.249-254
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• 1997

식품에의 사용이 확대되고 있는 고감미 천연 감미료인 스테비오시드의 단맛을 개선하기 위하여 CGTase를 이용한 당전이 반응 조건을 연구하였다. 당전이율을 높이기 위한 당전이 반응의 최적조건을 구하기 위하여 $L_{18}\;(2^{1}{\times}3^{7})$ 직교배열표로부터 18개 실험구를 선정하여 실험하였고 그 실험 결과를 분간 분석하였다. 그 결과 전이율에 가장 큰 영향을 주는 인자는 온도, 스테비오시드에 대한 말토덱스트린의 비, pH, 당공여체의 DE 값, 스테비오시드 농도 순이었으며, 각각의 조건이 $80^{\circ}C$, 말토덱스트린/스테비오시드=1.0, pH 6.0, 그리고 말토덱스트린의 DE가 15 일 때 최적 반응조건임을 확인하였다. 선정된 최적조건이 통계적으로 유의한지를 확인하기 위하여 3회의 반복 확인 실험을 한 결과 재현성이 있었고, 3회의 전이율이 모두 95% 신뢰 구간 안에 포함되어 통계적으로 유의함을 확인하였다. 그리고 최적조건에서의 효소 첨가량 및 당전이 시간은 각각 0.2%와 40시간이 적합한 것으로 나타났고, 이러한 조건에서 스테비오시드의 당전이를 실시한 결과 전이율 68%의 단맛이 우수한 당전이 스테비오시드를 제조할 수 있었다.