• 한국컴퓨터정보학회논문지
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• 제15권6호
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• pp.65-72
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• 2010

에드 혹 네트워크의 각 무선 단말기는 배터리 기반의 제한된 에너지로 동작하기 때문에 효율적인 에너지 사용에 관한 문제는 아주 중요하다. 시스템 수명을 연장하기 위해서는 단말 노드의 에너지 소비를 균형있게 유도하여 어느 특정 단말기의 에너지가 먼저 고갈되어 통신 단절을 초래하는 상황을 지연시켜야 한다. 또한 단말기 노드의 빈번한 이동 등으로 인해 신뢰성이 낮은 링크는 경로 설정시 고려해야 할 요소이다. 본 논문에서 제안하는 CMLR 방법은 잔여 에너지와 링크 에러율, 전송 소비 에너지를 고려한 새로운 비용 관계식을 이용하여 에너지 사용의 효율성을 증가시킨다. 이 방법은 전송 에너지 소모의 최소화와 노드 수명의 최대화 사이의 값을 절충하여 에너지 효율성을 높이고 균형있는 에너지 소비를 유도하여 네트워크 수명을 연장시키도록 하는 방법이다. 또한, 본 논문에서는 시뮬레이션을 통해 제안하는 CMLR의 성능을 검증하였으며, 네트워크 수명과 경로의 효율성 측면에서 볼 때 기존의 알고리즘보다 우수한 결과를 보여주었다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.303-306
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• 2011

Although PV module manufacturing and its structure are simple, the semi-permanent products can be used out doors for more than twenty years. Therefore it is need to choose proper materials and optimize manufacturing process. This paper suggest that factors of degradation need to be studied to achieve a more understanding of PV module Degradation rates and material failure. Nowadays durability of the PV Module is very important to sustain output safety for obtaining reliability. This paper is about the experiment that soldering uniformity of soldering process and to make least void from soldering process. From This study soldering flux residue and soldering method is main factor to form void blocked soldering uniformity and by using this.

• Journal of Microbiology and Biotechnology
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• 제24권11호
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• pp.1551-1558
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• 2014

The esterase gene Est8 from the thermophilic bacterium Bacillus sp. K91 was cloned and expressed in Escherichia coli. The monomeric enzyme exhibited a theoretical molecular mass of 24.5 kDa and an optimal activity around $50^{\circ}C$ at pH 9.0. A model of Est8 was constructed using a hypothetical YxiM precursor structure (2O14_A) from Bacillus subtilis as template. The structure showed an ${\alpha}/{\beta}$-hydrolase fold and indicated the presence of a typical catalytic triad consisting of Ser-11, Asp-182, and His-185, which were investigated by site-directed replacements coupled with kinetic characterization. Asp-182 and His-185 residues were more critical than the Ser-11 residue in the catalytic activity of Est8. A comparison of the amino acid sequence showed that Est8 could be grouped into the GDSL family and further classified as an SGNH hydrolase. Est8 is a new member of the SGNH hydrolase subfamily and may employ a different catalytic mechanism.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1997년도 춘계학술발표회논문집(2)
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• pp.439-444
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• 1997

In order to investigate organic association of fallout cesium, strontium and plutonium in the soil, soil samples influenced by fallout from nuclear weapon testings were treated with alkali (0.1 M-sodium hydroxide solution) to extract organic acids. After extraction, the resultant three fractions (sedimentary residue, humic and fulvic acid fractions) were subjected to the r-ray spectrometric analysis for $^{137}$ Cs, and radiochemical analysis for gosr and $^{239,240}$Pu. Alkali extraction experiments showed that a lot of $^{ 239,240}$Pu was extracted to organic acids from the soil samples, whereas most of $^{137}$ Cs and $^{90}$ Sr remained in residual fraction. Less than 10% of the total $^{137}$ Cs and $^{90}$ Sr was found in the organic fraction. The concentrations of $^{137}$ Cs and $^{90}$ Sr associated with humic fractions were higher than those with the corresponding fulvic fractions. It was found that more than 40% of the total $^{239,240}$Pu was associated with the organic fraction of soils. In contrast with $^{137}$ Cs and $^{90}$ Sr, $^{239,240}$Pu associated with vulvic fractions was much higher than in humic fractions.

• Journal of Forest and Environmental Science
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• 제20권1호
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• pp.110-130
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• 2004

본 연구에서는 대체에너지로서의 바이오매스에너지원의 정의와 특성 등을 살펴보고, 국내에서의 바이오매스 에너지원의 잠재력과 이용가능성에 대해서 검토하였다. 특히 임지잔재, 간벌재 등의 목질바이오매스는 자원량이 풍부하고, 임업 임산업의 활성화와 인공림의 간벌작업을 촉진하여 산림의 공익적 기능을 증대시킬 수 있는 에너지 자원으로서, 앞으로 지속적인 산림관리를 위한 새로운 임업의 과제가 될 것으로 판단된다.

• Bulletin of the Korean Chemical Society
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• 제33권3호
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• pp.848-854
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• 2012

We have studied the oligomerization of a fibril-forming segment of ${\alpha}$-Synulcein using a replica exchange molecular dynamics (REMD) simulation. The simulation was performed with trimers and tetramers of a 12 amino acid residue stretch (residues 71-82) of ${\alpha}$-Synulcein. From extensive REMD simulations, we observed the spontaneous formation of both trimer and tetramer, demonstrating the self-aggregating and fibril-forming properties of the peptides. Secondary structure profile and clustering analysis illustrated that antiparallel ${\beta}$-sheet structures are major species corresponding to the global free energy minimum. As the size of the oligomer increases from a dimer to a tetramer, conformational stability is increased. We examined the evolution of simple order parameters and their free energy profiles to identify the process of aggregation. It was found that the degree of aggregation increased as time passed. Tetramer formation was slower than trimer formation and a transition in order parameters was observed, indicating the full development of tetramer conformation which is more stable than that of the trimer. The shape of free energy surface and change of order parameter distributions indicate that the oligomer formation follows a dock-and-lock process.

• 에너지공학
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• 제26권2호
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• pp.39-49
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• 2017

Coffee is one of the most popular and consumed beverages in the world, which leads to a high contents of solid residue known as spent coffee grounds (SCG). As is known, coffee beans contain several classes of health related chemicals, including phenolic compounds, melanoidins, diterpenes, xanthines and carotenoids. The waste water coming out of coffee industries has high concentration of organic pollutants and is very harmful for surrounding water bodies, human health and aquatic life if discharged directly into the surface waters. Hence it is essential to treat and manage the coffee waste. Oyster shells are a waste product from mariculture that creates a major disposal problem in coastal regions of southeast Korea. In the study, the oyster shell waste was used to treat the coffee waste and its effluents. Oyster shells are calcined at $1000^{\circ}C$ for 2 h, and allowed to test the calcined CaO powder ability to inhibit the growth of bacteria in different aging coffee wastes. Calcined oyster shell powder showed anti-bacterial effect that inhibited cell growth of Escherichia coli and other bacterial forms. The antimicrobial activity of calcium oxide from oyster shell waste for biological treatment and utilization as a fertilizers with economic ecofriendly in nature.

• 한국연소학회지
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• 제20권2호
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• pp.36-39
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• 2015

The combustion characteristics of metal fiber burner fueled natural gas with tail gas produced from reforming process were analyzed on the point of flame stability and excess air conditions. Also, it was analyzed the effect of energy efficiency improvement due to decrease the fuel input in reforming system by using residue gases. As a results, it was confirmed that tail gas including hydrogen, CO and $CO_2$ could be directly injected without any change of air control system in natural gas burner and also energy efficiency was increased up to 30% maintained stable combustion.

• 한국식품과학회지
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• 제12권3호
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• pp.216-218
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• 1980

국내산 식물성(植物性) 기름 중 유기염소계 살초제(殺楚劑)의 잔류량(殘留量)을 평가하기 위하여 국내 주요도시에서 판매되는 1976년산 평지씨기름, 쌀겨기름, 참기름, 들기름 및 옥수수기름 43개 시료를 수집하여 기체크로마토그래피에 의하여 분석한 결과는 다음과 같다. 잔류수준(殘留水準)은 농약의 성분, 기름의 종류 및 생산지역에 따라 달리 나타났다. 각 잔류성분(殘留成分)의 전체기름에 대한 평균치는 total BHC 0.010 ppm, heptachlor 0.008 ppm, heptachlor epoxide 0.004ppm, aldrin <0.001 ppm, dieldrin 0.006 ppm, endrin 0.008 ppm, DDT 0.028 ppm이었다.

• Bulletin of the Korean Chemical Society
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• 제31권10호
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• pp.2903-2908
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• 2010

Protein S-nitrosation is common in cells under nitrosative stress. In order to model proteins with S-nitrosocysteine (CysSNO) residues, we first developed an Amber force field for S-nitrosoethanethiol (EtSNO) and then transferred it to CysSNO. Partial atomic charges for EtSNO and CysSNO were obtained by a restrained electrostatic potential approach to be compatible with the Amber-99 force field. The force field parameters for bonds and angles in EtSNO were obtained from a generalized Amber force field (GAFF) by running the Antechamber module of the Amber software package. The GAFF parameters for the CC-SN and CS-NO dihedrals were not accurate and thus determined anew. The CC-SN and CS-NO torsional energy profiles of EtSNO were calculated quantum mechanically at the level of B3LYP/cc-pVTZ//HF/6-$31G^*$. Torsional force constants were obtained by fitting the theoretical torsional energies with those obtained from molecular mechanics energy minimization. These parameters for EtSNO reproduced, to a reasonable accuracy, the corresponding torsional energy profiles of the capped tripeptide ACE-CysSNO-NME as well as their structures obtained from quantum mechanical geometry optimization. A molecular dynamics simulation of myoglobin with a CysSNO residue produced a well-behaved trajectory demonstrating that the parameters may be used in modeling other S-nitrosated proteins.