• International journal of advanced smart convergence
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• 제4권1호
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• pp.162-178
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• 2015

Petroleum based fossil fuels used to power most processes today are non-renewable fuels. This means that once used, they cannot be reproduced for a very long time. The maximum combustion of fossil fuels occurs in automobiles i.e. the vehicles we drive every day. Thus, there is a requirement to shift from these non-renenewable sources of energy to sources that are renewable and environment friendly. This is causing the need to shift towards more environmentally-sustainable transport fuels, preferably derived from biomass, such as biodiesel blends. These blends can be made from oils that are available in abundance or as waste e.g. waste cooking oil, animal fat, oil from seeds, oil from algae etc. Waste Cooking Oil(WCO) is a waste product and so, converting it into a transportation fuel is considered highly environmentally sustainable. Keeping this in mind, a life cycle assessment (LCA) was performed to evaluate the environmental implications of replacing diesel fuel with WCO biodiesel blends in a regular Diesel engine. This study uses Life Cycle Assessment (LCA) to determine the environmental outcomes of biodiesel from WCO in terms of global warming potential, life cycle energy efficiency (LCEE) and fossil energy ratio (FER) using the life cycle inventory and the openLCA software, version 1.3.4: 2007 - 2013 GreenDelta. This study resulted in the conclusion that the biodiesel production process from WCO in particular is more environmentally sustainable as compared to the preparation of diesel from raw oil, also taking into account the combustion products that are released into the atmosphere as exhaust emissions.

• Asian Pacific Journal of Cancer Prevention
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• 제15권3호
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• pp.1339-1344
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• 2014

Aims: Alterations in mitochondrial DNA (mtDNA) have been implicated in carcinogenesis and tumor progression. We here evaluated the diagnostic and prognostic potential of mtDNA as a biomarker for breast cancer. Methods: Using multiplex real-time polymerase chain reaction, nuclear DNA (nDNA) and mtDNA levels in serum, buffy coat, tumor, and tumor-adjacent tissue samples from 50 breast cancer patients were determined and assessed for associations with clinicopathological features. To evaluate mtDNA as a biomarker for distinguishing between the four sample types, we created receiver operating characteristic (ROC) curves. Results: The mtDNA levels in buffy coat were significantly lower than in other sample types. Relative to tumor-adjacent tissue, reduced levels of mtDNA were identified in buffy coat and tumor tissue but not in serum. According to ROC curve analysis, mtDNA levels could be used to distinguish between buffy coat and tumor-adjacent tissue samples with good sensitivity (77%) and specificity (83%). Moreover, mtDNA levels in serum and tumor tissue were positively associated with cancer TMN stage. Conclusions: The mtDNA levels in blood samples may represent a promising, non-invasive biomarker in breast cancer patients. Additional, large-scale validation studies are required to establish the potential use of mtDNA levels in the early diagnosis and monitoring of breast cancer.

• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1439-1446
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• 2009

Isocarbophos is a widely used organophosphorus insecticide that has caused environmental pollution in many areas. However, degradation of isocarbophos by pure cultures has not been extensively studied, and the degradation pathway has not been determined. In this paper, a highly effective isocarbophos-degrading strain, scl-2, was isolated from isocarbophos-polluted soil. The strain scl-2 was preliminarily identified as Arthrobacter sp. based on its morphological, physiological, and biochemical properties, as well as 16S rDNA analysis. The strain scl-2 could utilize isocarbophos as its sole source of carbon and phosphorus for growth. One hundred mg/l isocarbophos could be degraded to a non detectable level in 18 h by scl-2 in cell culture, and isofenphos-methyl, profenofos, and phosmet could also be degraded. During the degradation of isocarbophos, the metabolites isopropyl salicylate, salicylate, and gentisate were detected and identified based on MS/MS analysis and their retention times in HPLC. Transformation of gentisate to pyruvate and fumarate via maleylpyruvate and fumarylpyruvate was detected by assaying for the activities of gentisate 1,2-dioxygenase (GDO) and maleylpyruvate isomerase. Therefore, we have identified the degradation pathway of isocarbophos in Arthrobacter sp. scl-2 for the first time. This study highlights an important potential use of the strain scl-2 for the cleanup of environmental contamination by isocarbophos and presents a mechanism of isocarbophos metabolism.

• 디자인학연구
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• 제15권4호
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• pp.253-262
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• 2002

애니메이션(animation)은 원천적으로 시간(time)의 개입이 없이는 움직임(motion)의 생성이 불가능하다. 그러므로 시간의 개념은 애니메이션의 형식적 존재를 가능하게 하는 실질적인 요소들 중 하나이다. 애니메이션의 주관적인 내면세계의 표현은 객관적인 외면세계의 표현에 비해 다소 난해하므로 애니메이션에서의 다양한 시간적 변형을 통해 표현 영역을 확대시킬 필요를 느낀다. 영상언어적인 다양한 표현을 위하여 시간의 개념을 일상적인 시간과 애니메이션적인 시간으로 나누어 볼 수 있다. 먼저 일상적인 시간은 단순하고 애니메이션적인 시간은 복잡하며 다양하다. 또한 일상적인 시간이 선형적이고 환원 불가능하고 아날로그적인 형태를 소유한다면 애니메이션적인 시간은 다방향적이고 환원 가능하며 디지털적인 성격을 취한다. 일상적인 시간은 자연을 통한 경험에서 터득되지만 애니메이션적인 새로운 개념의 시간은 애니메이션의 영상 매체를 통해서 생성이 되고 경험이 된다. 일상적인 시간과 애니메이션적인 시간의 차이와 종류 그리고 편집에서 표현되는 시간의 종류를 분석하고 애니메이션에서 적용 방안과 사례들을 들어 본다. 결론적으로 애니메이션적인 시간은 변형이 가능한 특성을 지녔기 때문에 다양하고 풍부한 영상 언어(film language)로써의 역할을 가능하게 한다. 즉, 시간의 개념이 하나의 표현 도구로써 유용하게 사용될 수 있기 때문이다. 본 연구는 애니메이션의 시간에 관한 영상 언어적인 역할 연구로써 애니메이션을 영상 미학적인 차원으로 발전시킬 수 있는 토대가 될 것이다.

• 한국기계가공학회지
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• 제17권1호
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• pp.130-137
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• 2018

In long freight trains, there is a brake time delay in the neighboring freight cars that causes damage and fractures of couplers, especially the knuckle of them. If there is a problem for couplers in the cars, this could cause a derailment and lead to damage of human life and property damage. In this study, maximum forces on the couplers are studied when a long freight car brakes, with brake delay time and coupler gap. We have made a dynamic model of 50 freight cars and couplers, applying contact between couplers and a characteristic curve for expressing force and displacement of buffers with SIMPACK, a multi-body dynamics program. We use EN 14531-2 from the British Standards Institution, a standard of freight car brakes for the verification of the dynamic model. We also use a simplified method to analyze the dynamic model of 50 freight cars. With changing coupler gap and brake delay time, we do comparative analysis with AAR M-201 from the Association of American Railroads, a standard of AAR couplers. From this result, we find that the standard on fatigue limit is satisfied, such that the brake delay time is within 0.06 second if the coupler gap of the AAR coupler is within 20 millimeters.

• Smart Structures and Systems
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• 제13권2호
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• pp.177-201
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• 2014

With the increased size and flexibility of the tower and blades, structural vibrations are becoming a limiting factor towards the design of even larger and more powerful wind turbines. Research into the use of vibration mitigation devices in the turbine tower has been carried out but the use of dampers in the blades has yet to be investigated in detail. Mitigating vibrations will increase the design life and hence economic viability of the turbine blades and allow for continual operation with decreased downtime. The aim of this paper is to investigate the effectiveness of Semi-Active Tuned Mass Dampers (STMDs) in reducing the edgewise vibrations in the turbine blades. A frequency tracking algorithm based on the Short Time Fourier Transform (STFT) technique is used to tune the damper. A theoretical model has been developed to capture the dynamic behaviour of the blades including the coupling with the tower to accurately model the dynamics of the entire turbine structure. The resulting model consists of time dependent equations of motion and negative damping terms due to the coupling present in the system. The performances of the STMDs based vibration controller have been tested under different loading and operating conditions. Numerical analysis has shown that variation in certain parameters of the system, along with the time varying nature of the system matrices has led to the need for STMDs to allow for real-time tuning to the resonant frequencies of the system.

• 디지털융복합연구
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• 제20권3호
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• pp.507-516
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• 2022

본 연구의 목적은 청소년들이 인지하는 행복감에 따라 스마트폰 사용시간에 영향을 미치는 요인을 파악하는 것이다. 본 연구에서는 질병관리청 홈페이지를 통해 제13차(2017) 청소년 건강행태 온라인 설문조사 원자료 사용 승인절차를 거쳐 만 12-18세 54,603명을 연구 대상자로 선정하였다. 자료는 IBM SPSS 23.0 프로그램을 이용하여 가중치를 부연한 후 복합 샘플 계획 파일을 생성하여 분석하였다. 행복한 그룹과 행복하지 않은 그룹의 스마트폰 사용에 따른 일반적 특성과 신체, 심리적 특성 간에는 유의한 차이가 나타났다(p<.05). 그리고 스마트폰 사용시간에 영향을 미치는 요인은 행복하다고 인식한 청소년 그룹과 행복하지 않다고 인식한 청소년 그룹 간에 통계적으로 유의한 차이가 있었다. 그러므로 청소년들의 올바른 스마트폰 사용으로 행복도를 높여 삶의 질을 향상시킬 필요가 있다.

• 한국재난정보학회 논문집
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• 제19권3호
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• pp.729-736
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• 2023

연구목적:광역권 통근시간 만족도 향상요인 분석에 따른 대중교통 이용 활성화 방안에 목적이 있다. 연구방법: 본 연구는 광역통근을 시행하는 직장인을 대상으로 광역통근시간 및 만족도에 영향을 미치는 요인을 분석하였다. 연구결과: 권역별 광역통근시간에 대한 통근만족도의 경우, 수도권은 평균 통근시간이 높은 만큼 통근시간만족도가 상대적으로 낮으며, 비수도권은 평균 통근시간이 낮은 만큼 통근시간 만족도가 상대적으로 높게 나타났다. 결론:향후 정부는 광역통근 시간을 줄이기 위한 방안으로 급행철도 및 광역버스를 신설 또는 개선하고, 승용차의 이용시간 단축을 위한 도시고속도로 등을 건설하여 통근시간을 줄이는 양적지표도 중요하지만 통근시간의 만족도를 높이는 질적 지표가 더욱 중요하다. 즉, 통근시간이 길어도 그 시간이 만족스러우면 삶의 만족도 역시 높아지므로 삶의 질이 중요한 시대를 맞이하여 통근시간이라는 단순 지표보다는 통근시간 만족도까지 개선시킬 필요가 있어 통근시간에 대한 질적 및 양적 측면 모두 개선이 필요하다.

• 식물조직배양학회지
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• 제27권4호
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• pp.325-337
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• 2000

All living organisms depend on soil and water for their sustained growth and development. In recent years, sustenance of life in these growth matrices has been adversely affected by the cumulative increase in environmental pollutants resulting from increasing population, growing economies and resource-use. This review provides a glimpse into the problem of global environmental pollution, the traditional technologies available for remediation and the scope of emerging‘plant-based remediation’technologies. Phytoremediation, the use of plants to effectively remove or stabilize contaminants from the growth substrate, is a low cost and ecologically friendly alternative to the common‘dig and dump’technologies. The field of phytoremediation has been driven by the intrinsic need for identification of ideal candidate plant species. To date, there are only a very few identified plants which satisfy all of the prerequisites for use in phytoremediation. The review focuses on one such plant species, the common horticultural plant scented geranium (Pelargonium sp.), with demonstrated potential to remediate metal / salt contaminated soils / aqueous systems. The characterization of tolerance and metal / salt accumulation potential of Pelargonium sp. and its efficacy in remediating complex contaminated sites are described. The unique ability of scented geraniums to tolerate excessive amounts of multi-metals, hydrocarbon and salt mixtures, and at the same time to accumulate significant amounts of metal and salt ions in the biomass, renders this plant species as one of the ideal candidates for remediation.

• 융합보안논문지
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• 제15권6_2호
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• pp.89-97
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• 2015

스마트폰은 PC의 소형화된 운영 체제를 탑재한 기기에 무선전화가 가능한 하드웨어와 소프트웨어 모듈이 추가된 휴대 전화이다. 본 연구는 연령별로 스마트폰이 보급 확대되는 과정 및 특성에 대해 살펴보고자 한다. 또한 KISA와 KISDI의 설문조사를 참고하여 스마트폰을 통한 미디어 이용 행태의 연령별 특징에 대해 조사해 보고자 한다. 스마트폰은 손쉽게 사용이 간편하고 소형 PC와 같아 휴대성과 이동성이 뛰어나다. 시간과 장소의 영향을 받지 않고 언제 어디서나 정보 및 자료 검색이 용이하다. 사진 및 동영상의 촬영이나 저장이 용이하고 여러 지인들과 다양한 정보교류가 가능하다. 모든 연령대에서 스마트폰을 널리 사용하여 삶의 만족도가 향상되었으면 한다.