• 정보처리학회논문지C
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• 제16C권5호
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• pp.629-636
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• 2009

무선 센서 네트워크에 사용되는 센서들은 제한된 배터리에 의해서 가동되며 배터리의 수명이 다하면 센서 네트워크가 정상적으로 동작할 수 없으므로 각 센서들의 에너지를 효과적으로 사용하는 라우팅 기법이 사용되어야 한다. 이러한 라우팅 기법 중에 가장 널리 알려진 기법이 LEACH와 PEGASIS 기법이나 LEACH(혹은 LEACH-C) 기법은 헤드 노드의 전력 소모가 심하여 다른 노드보다 먼저 수명을 다하는 단점이 있으며 PEGASIS 기법은 LEACH 기법보다 성능이 우수한 것으로 알려져 있으나 소스 노드에서 싱크노드로 데이터를 전송하기 위해 매우 긴홉을 통과하여 데이터가 전달되기 때문에 전송시간이 길고 싱크 노드에 가까운 노드들의 에너지 소모가 급격하게 진행된다는 단점이 있다. 본 논문에서는 LEACH의 클러스터링 기법과 PEGASIS 기법 체인연결 기법을 혼합하여 사용함으로써 센서네트워크를 보다 오래 사용할 수 있는 하이브리드 기법을 제시하였으며 LEACH-C 기법보다는 33% PEGASIS 기법보다는 18%의 성능의 향상을 가져올 수 있었다.

• 대한수학회보
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• 제45권4호
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• pp.621-629
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• 2008

Let R be a prime ring of characteristic different from 2, C the extended centroid of R, and $\delta$ a generalized derivations of R. If [[$\delta(x)$, x], $\delta(x)$] = 0 for all $x\;{\in}\;R$ then either R is commutative or $\delta(x)\;=\;ax$ for all $x\;{\in}\;R$ and some $a\;{\in}\;C$. We also obtain some related result in case R is a Banach algebra and $\delta$ is either continuous or spectrally bounded.

• 대한화학회지
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• 제24권3호
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• pp.193-200
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• 1980

N-Acetyl-L-cysteine, $C_5H_9NO_3S,$의 결정 및 분자구조를 X-선 회절법으로 연구하였다. 이 화합물의 결정은 삼사비등축정계에 속하며 공간군은 $P_1$이다. 단위세포상수는 a = 7.04(3), b = 5.14(2), c = 8.25(3)${\AA}$, ${\alpha}$ = 106(2), ${\beta}$ = 51(1), ${\gamma}$ = 124(2)$^{\circ}$이고, 단위세포는 분자 한개만을 포함하고 있다. Weissenberg 사진촬영으로 얻은 회절반점의 총수는 629개이며 direct method를 적용하여 구조해명을 한 후 full matrix least-squares method로 정밀화하였으며 최종 R값은 0.12이다. C-카르복실기 및 N-아세틸기의 원자들은 각각 평면을 이루고 있다. 카르복실기의 산소원자 O(1)은 이웃분자의 아세틸기의 산소원자 O(3)와 $O-H{\cdot}{\cdot}{\cdot}O$ 수소결합을 하며 그 길이는 2.59${\AA}$이다.

• Bulletin of the Korean Chemical Society
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• 제28권4호
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• pp.629-634
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• 2007

Photochemical reactions of N-methylphthalimide with silyl enol ethers have been explored. Irradiations of phthalimide (1) and cyclic silyl enol ethers (5a-b) are observed to promote formation of photoreduced phthalimides and photoaddition products by sequential SET-desilylation pathways. The photoreaction of phthalimide (1) and acyclic silyl enol ethers (5c-d) leads to produce oxetanes which arise by competitive single electron transfer (SET) and classical 2+2 photocycloaddition (Parteno-Buchi reaction) pathways.

• Bulletin of the Korean Chemical Society
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• 제12권6호
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• pp.629-632
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• 1991

The rate constants for the formation and dissociation of nickel(II) and cobalt(II) complexes with mandelate have been determined by the pressure-jump relaxation study. The forward and reverse rate constants for the mandelate complex formation reactions were obtained to be $k_f=3.60{\times}10^4\;M^{-1}s^{-1}$ and $k_r=1.73{\times}10^2\;s^{-1}$ for the nickel(II), and $k_f=1.75{\times}10^5\;M^{-1}s{-1}$ and $2.33{\times}10^3\;s^{-1}$ for the cobalt(II) in aqueous solution of zero ionic strength ($(\mu{\to}0)\;at\;25^{\circ}C$. The results were interpreted by the use of the multistep complex formation mechanism. The rate constants evaluated for each individual steps in the multistep mechanism draw a conclusion that the rate of the reaction would be controlled by the chelate ring closure step in concert with the solvent exchange step in the nickel(II) complexation, while solely by the chelate ring closure step for the cobalt(II) complex.

• 한국통신학회논문지
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• 제36권10C호
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• pp.629-634
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• 2011

주차장에서 빈 공간을 분석하는 기술은 주차공간의 효율적인 사용이나 교통이 혼잡한 곳에서 유용하게 사용될 수 있다. 그러나 기존의 주차 공간 분석 방법은 실용적이지 못하거나 빠른 처리속도가 필요하다. 그래서 본 논문에서는 실시간 주차검출에 적합한 주차 모니터링 방법을 제안하고자 한다. 제안된 방법은 그레이레벨 영상을 이용하여 주차여부를 확인하고, 주차공간을 분석하는 방법을 사용하였다. 제안된 방법의 성능을 확인하기 위해 야외 주차장에서 129개의 동영상을 획득하여 실험한 결과 98.5%의 주차 공간 분석에 성공하여 제안된 방법이 주차 공간 분석에 효율적인 것을 입증하였다.

• 한국수산과학회지
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• 제43권6호
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• pp.629-636
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• 2010

A simple, rapid method for determining amoxicillin (AMO) and ampicillin (AMP) in aquatic products (flatfish, salmon, shrimp, tilapia, and yellow croaker) was evaluated. For quantification, the AMO and AMP ions at m/z 348.9 and 105.9, respectively, were selected. The limit of detection (LOD) and limit of quantification (LOQ) for detecting AMO were 0.09 and $0.25\;{\mu}g/L$, respectively. The respective values for AMP were 0.02 and $0.05\;{\mu}g/L$. After $100\;{\mu}g/L$ AMO treatment, the level decreased 10% after 7 days at $5^{\circ}C$, while it decreased 20% at $25^{\circ}C$. After 7 days, 94.9.100% of $100\;{\mu}g/L$ AMP remained after storage at $5^{\circ}C$, while 62.3.100% remained after storage at $25^{\circ}C$. Using the food code method, the recovery of AMO ranged from 64.1.92.0% and that of AMP from 44.8.86.2%. With a protein centrifugation method, the recovery of AMO ranged from 39.8.87.9% and that of AMP from 78.0.98.1%. With liquid-liquid extraction, the recovery of AMO ranged from 36.5.88.3% and that of AMP from 31.8.75.1%.

• 대한금속재료학회지
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• 제50권9호
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• pp.629-636
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• 2012

Volume shrinkage behavior accompanying the cure of resin formulations might be a critical factor when assembly processes using polymer materials are considered. In this study, cure shrinkage behavior with respect to resin formulation type and heating method was measured on sandwich structure samples by a thermomechanical analyzer (TMA). Quartz, used as a cover material for the sandwich structure, indicated the coefficient of thermal expansion close to $0ppm/^{\circ}C$. When a dynamic heating mode was conducted, a squeeze-out region and a cross-linking region for each resin formulation could be separated clearly with overlapping differential scanning calorimeter results on the TMA results. In addition, a cure shrinkage dominant region and a thermal expansion dominant region in the cross-linking region were distinguished. Consequently, the degree of cure at the initiation of the thermal expansion dominant region was successfully measured. Measurement of all resin formulations indicated the thermal expansion behavior exceeded cure shrinkage before full cure.

• Asian-Australasian Journal of Animal Sciences
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• 제10권6호
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• pp.629-634
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• 1997

An experiment was conducted to investigate the effects of equiprotein replacement of dietary fish meal (FM) with duckweed (DW) and soybean meal (SBM) on the performance of broilers. A total of 112 seven-day-old as hatched broilers were fed on 4 different iso-energetic (2,818 kcal/kg) and iso-nitrogeneous (20.2% CP) diets up to 56 days of age. Diet A was control with 12% FM. In diets B (3% DW + 13.5% SBM), C (6% DW + 11.5% SBM) and D (9% DW +10% SBM). All FM protein of control diet was replaced by DW and SBM. The replacement of dietary FM by DW and SBM depressed feed intake, live weight gain and feed conversion efficiency and increased production cost and thus affected profitability. All those growth parameters had a linear declining trend as the proportion of DW in the diet was increased. It may be concluded that complete replacement of dietary FM by DW and SBM should not be recommended for raising broilers.

• 한국소음진동공학회논문집
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• 제20권7호
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• pp.629-636
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• 2010

A Mobile Harbor is a new transportation platform which can load and unload has containers to and from very large container ships on the sea. Currently designed Mobile Harbor a catamaran type which is equipped with precisely controlled gantry crane on the deck, and can transport 250 TEUs at a time. Loading and unloading works by crane require very small motion of Mobile Harbor in waves, because it may be operated outside of harbors. In this project, applicability of both tuned-type anti-rolling tank and maglev-type active mass driver is studied as anti-rolling systems.