• Bulletin of the Korean Chemical Society
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• 제34권11호
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• pp.3391-3398
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• 2013

The carboxylated multiwall carbon nanotubes (MWCNT-COOH) and functionalized with isatin derivative (MWCNT-isatin) have been used as efficient adsorbents for the removal of lead (Pb) from aqueous solutions. The influence of variables including pH, concentration of the lead, amount of adsorbents and contact time was investigated by the batch method. The adsorption of the lead ions from aqueous solution by modified MWCNTs was studied kinetically using different kinetic models. The kinetic data were fitted with pseudo-first-order, pseudo-second-order, and intra-particle diffusion models. The sorption process with MWCNT-COOH and MWCNT-isatin was well described by pseudo-second-order and pseudo-first-order kinetics, respectively which it was agreed well with the experimental data. Also, it involved the particle-diffusion mechanism. The values of regression coefficient of various adsorption isotherm models like Langmuir, Freundlich and Tempkin to obtain the characteristic parameters of each model have been carried out. The Langmuir isotherm was found to best represent the measured sorption data for both adsorbent.

• 동굴
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• 제84호
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• pp.22-30
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• 2008

With activation plan of Speleological Society of Korean like home page of Speleological Society of Japan cave crane information, caving information, cave Q/A, cave publication, the relation site back the possibility of seeing information regarding the cave which is various in order to be, it reorganizes. The possibility of coming in contact in order to be, various branch information also the general rain specialist regarding the cave resources. Currently the possibility of seeing the various branch data for the application of the cave resources at any time it is, home page of Speleological Society of Korean the possibility of doing to lead in order to be, it proposes the plan. From one person it will be able to study the data regarding the cave of various field in order, all curricular materials regarding the cave resources the educational program which leads a home page about under developing it proposes the activation plan of the cave resources.

• 산업경영시스템학회지
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• 제23권60호
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• pp.11-22
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• 2000

The main objective of this research is to analyze an order point and an order quantity of a distribution center and each branch to attain a target service level in multi-level inventory distribution system. In case of product item, we use the item with low volume of average monthly demand. Under the continuous review method, the distribution center places a particular order quantity to an outside supplier whenever the level of inventory reaches an order point, and receives the order quantity after elapsing a certain lead time. Also, each branch places an order quantity to the distribution center whenever the level of inventory reaches an order point, and receives the quantity after elapsing a particular lead time. When an out of stock condition occurs, we assume that the item is backordered. For considering more realistic situations, we use generic type of probability distribution of lead times. In the variable lead time model, the actually achieved service level is estimated as the expected service level. Therefore, this study focuses on the analysis of deciding the optimal order point and order quantity to achieve a target service level at each depot as a expected service level, while the system-wide inventory level is minimized. In addition, we analyze the order level as a maximum level of inventory to suggest more efficient way to develop the low demand item model.

• Spatial Information Research
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• 제5권1호
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• pp.11-26
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• 1997

본 논문은 제2의 금융중심지로 부상하고 있는 강남구를 사례로 GIS 기법을 활용하여 은행점포의 입지를 분석하였다. 금융자율화 이후 급격한 증가추세를 보이고 있는 은행점포의 수는 상당한 지역적인 편재현상을 나타내고 있다. 통계기법을 활용하여 은행 입지에 영향을 주는 입지요인을 추출하였고, 은행이용 고객들에 대한 설문조사를 통하여 은행점포의 상권을 조사하였다. 이러한 기초자료를 바탕으로 하여 GIS기법을 활용하여 입지분석을 실시하였다. 먼저 은행이용고객들에게 최적의 서비스를 공급할 수 있는 목적함수를 토대로한 입지-배분 모델을 적용하여 추출된 입지와 현재의 은행점포의 입지를 비교하였다. 또한 그리드 연산 기법을 활용하여 잠재 수요력과 잠재 공급력의 차이를 통해 앞으로 은행점포의 신규 설립이 가능한 지구를 추출하였다. 본 연구를 통해 GIS기법을 활용하여 입지분석을 실시하는 경우 제한점과 앞으로 해결되어야 할 문제점에 대해 논하였다.

• 임산에너지
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• 제22권1호
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• pp.49-57
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• 2003

경상남도 진해지역 30년생 편백 조림지를 대상으로 현존량을 추정하기 위하여 Urich II법에 의하여 수관급에 따른 부위별 현존량을 측정하여 생산구조를 해석하고 시료채취의 효율성을 높이기 위한 방법을 탐색하였다. 지상부 총 물질생산량은 137.3 ton/ha을 보유하고 있었으며, 이들 임목의 부위별 구성비는 줄기 71.8%, 가지 15.4%, 잎 12.8%로 나타났다. 임분에서 엽생산량은 수고 9.2∼11.2m에서 최대치를 보였으며, 현존량의 구성비는 우세목과 준우세목에서는 줄기>가지>잎, 열세목에서는 줄기>잎>가지 순으로 나타났다. 부위별 건조비는 줄기 47.3∼49.2%, 가지 48.8∼52.9%, 잎 39.2∼40.8%, 고사지 0.78%∼0.89%의 범위를 보였다. 표준목 전건비중(basic wood density)은 0.49∼0.53으로 나타났으나 수관급에 따른 표준목간 유의차는 나타나지 않았다.

• 한국통신학회논문지
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• 제17권10호
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• pp.1147-1156
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• 1992

본 논문에서는 $\pi/4$ shift QPSK에 Trellis 부호화된 변조 기법(Trellis-Coded Modulation. TCM)을 적용시키기위하여 $\pi/8$ shift 8PSK를 제안하고 위상차에 의한 신호 집합 확장과 신호 집합 분할을 수행하는 trellis 부호화된 π/8 shift 8PSK를 제안한다. 또한 BER(Bit Error Rate) 성능을 향상시키기위하여 제1차 위상차뿐만아니라 제L차 이상차의 자승 유클리드 거리를 매트릭(Branch Metric)으로 갖는 비터비 디코더(Viterbi decoder)를 설계한다. 그리고 $\pi/4$ shift QPSK, trellis 부호화된 $\pi/8$ shift 8PSK와 제L차 위상차의 자승 유클리드 거리를 메트릭(Branch Metric)으로 갖는 trellis 부호화된 $\pi/8$ shift 8PSK 의 BER 특성을 AWGN에서 Monte Carlo 시뮬레이션을 통해 알아본다. 제안된 알고리즘은 MDPSK에도 적용될 수 있다.

• 전자공학회논문지A
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• 제31A권6호
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• pp.1-8
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• 1994

In this paper, in order to apply the idea MDPSK to TCM, we use signal set expansion and set partition by phase differences. Through this we propose the trellis-coded MDPSK. And the Viterbi decoder containing branch metrics of the squared Euclidean distance of the Lth order phase difference as well as the first order phase difference is introduced in order to improve the bit error rate(BER) in the differential detection of the trellis-coded MDPSK. The proposed Viterbi decoder is conceptually same to the sliding multiple symbol dection method which uses the branch metric with the first and Lth order phase differences. We investigate the performance of the uncoded DQPSK and the trallis-coded D8PSK in additive white Gaussian noise (AWGN) through the Monte Carlo simulation under the two cases of using and not using the Lth order phase difference metric. The study shows that trellis-coded 8DPSK is an attractive scheme for power and bandlimited systems while also improving the BER performance when the Viterbi decoder is employed to the Lth order phase order difference metric. This performance improvement has been obtained without sacrificing the bandwidth or the power efficiency.

• 한국식품영양과학회지
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• 제3권1호
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• pp.7-11
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• 1974

Wistar Strain male rats were divided into four different diet groups and the control group was fed on seven percent casein diet (C), the second with a mixture of 80% of rice and 20% of buckwheat (RW), the third with rice only (R), and the fourth with a mixture of rice and buckwheat of equal nitrogen level (RWS). Each diet group consisted of six rats was fed for three weeks by the adlibitum feeding method. The results of the experiment, i, e, the growth gain and change in the level of branch-amino acids in the plasma determined by the micro-bioassay method were as follows. 1. The group C showed the largest growth gain and the rest did in the order of RW group, R group, and RWS group. 2. It was shown that rats fed on diet of higher protein score tend to have higher level of free branch-amino acids in the plasma. 3. Thus, the protein score may be estimated based on the level of the free branch-amino acids in the plasma.

• 한국산업융합학회 논문집
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• 제23권2_2호
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• pp.271-280
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• 2020

Due to the development of the urban economy, high-density buildings and skyscrapers have continued to increase in order to alleviate high population densities and to make efficient use of urban space. However, a fire in a high-rise building is a disaster that can lead to massive casualties and property damage because of the difficulty of firefighting and escaping. Various studies have been conducted on these high-rise buildings because they are sympathetic to these difficulties all over the world. In this paper, trends of researches and technologies related to fire in high-rise buildings are analyzed synthetically through thesis and patent data. In other words, we explored the trends of various studies that have been carried out so far through the thesis, and performed technical monitoring on actual implemented technology and newly implemented technologies through patent data. Through this research, we have studied the present and the future of technology for high-rise building fire.

• 대한수학회보
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• 제53권3호
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• pp.651-656
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• 2016

Let G be a finite group and nse(G) be the set of numbers of elements of G of the same order. In this paper, we prove that the simple group $Sz(2^{2m+1})$, where $2^{2m+1}-1$ is a prime number, is uniquely determined by $nse(Sz(2^{2m+1}))$ and ${\mid}Sz(2^{2m+1}){\mid}$.