• 한국생산제조학회지
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• 제5권3호
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• pp.31-39
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• 1996

The objective of this study is to investigate the influence of welding residual stresses on the fatigue crack growth behavior of cracks located transverse to the weld bead. For this purpose, G. T. A (Gas Tungsten Arc) welding was performed on hte Al alloy 1100-O plate and the same initial crack is made on HAZ(Heat Affected Zone), weld metal and base meta respectively. Specimens were used CT(Compact Tension) specimens. Initial welding residual stresses were measured by using strai gage sectioning method. All specimens were tested under constant amplitude load with stress ratio R=0.1, It is possible to predict fatigue crack growth behaviors and the fatigue life, using numerical analysis together with distribution of initial residual stress and the values of C and m obtained from $da/dN-{\Delta}K$

• 한국버섯학회지
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• 제12권2호
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• pp.88-95
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• 2014

Auricularia auricula-judae is an edible mushroom, which is known as wood ear, free ear, black ear mushroom, and free jelly fish. This study was carried out to obtain the basic information for mycelial culture conditions of Auricularia auriculajudae. According to colony diameter and mycelial density, the media for suitable mycelial growth were PDA and MCM. The optimum temperature for mycelial growth was $25{\sim}30^{\circ}C$. Carbon and nitrogen sources were mannose and malt extract, respectively. The optimum C/N ratio was in the range of 10 to 1 with 2% glucose. Other minor components for the optimal growth were thiamine-HCl and biotin as vitamins, succinic acid and lactic acid as organic acids, and $MgSO_4{\cdot}7H_2O$ and $KH_2PO_4$ as mineral salts.

• Bulletin of the Korean Chemical Society
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• 제35권8호
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• pp.2419-2422
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• 2014

The syntheses and crystal structures of a three-dimensional (3D) coordination network $[Zn_4(2-mBIM)_5-(C_2H_6NCOO)(HCOO)({\mu}-OH)]{\cdot}DMF$ ($1{\cdot}$DMF; 2-mBIM = 2-methylbenzimidazolate) and a two-dimensional (2D) layer $[Zn_2(2-mBIM)_3(HCOO)(H_2O)]{\cdot}DMF$ ($2{\cdot}DMF$) are reported. Different structures were produced depending on the ratio of reactants. Structurally, 1 illustrates the formation of a unique framework based on a 2-mBIM bridge with the side group on an imidazole ring, while 2 possesses a honeycomb layer built up purely from imidazolates. For gas sorption, $CO_2$ is adsorbed on the activated phase of 1 but $N_2$ is not taken up.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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• pp.143-148
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• 2005

Plastics and vinyl resin is generally used in the various fields of industry and daily life. Except incineration, most waste has been disposed finally in landfill and the leaching of plasticizer as DEHP(di 2-ethylhexyl phthalaet) has been taken place in the landfill. DEHP had been found. for endocrine disrupter by World Wild Life Fund and Japan. In this study aimed at estimation of capacity of adsorption and measurement of phthalate ester in the residual soil. The residual soil had been gathered from three closed landfill which was under stabilization with sorting and transferring. The Dibutyl phthalate and DEHP had been contained in all residual soil. Especially, resisual soil contained DEHP much more than peripheral soil. In J landfill residual soil, organic matter content, CEC and #200 sieve passing ratio is highest, and Freundlich isotherm sorption coefficient(K) and constant(1/n) is highest.

• Journal of Chest Surgery
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• 제24권4호
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• pp.382-389
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• 1991

The clinical observations on the 63 cases of the mitral valvular heart disease treated in the department of Thoracic and Cardiovascular Surgery, Kosin medical college, during the period of 5 years from January, 1986 to December, 1989, are as follows. 1. Total 63 cases, 23 were male and 40 were female with sex ratio of 1: 1.7. 2. The age distribution was widely varied from 7 years of the youngest to 65 years oldest, average age was 35.3 year old. 3. The main clinical symptom and sign were D.O.E, general weakness, fatigability, palpitation, chest pain, hepatomegaly, pitting edema and both neck vein distension. 4. The preoperative N.Y.H.A functional classification were class II, III, IV in 28%, 54%, 16%. 5. The preoperative diagnosis were MS - 6.3%, MR - 53.9%, MSR - 36.5%, MVP - 3.1%. 6. All 63 patients were operated on the under direct vision using extracorporeal circulation, MVR in 18 cases, MVR and Tricuspid annuloplasty in 24 cases, DVR in 3 cases, DVR and Tricuspid annuloplasty in 5 cases, TVR in 1 case, Mitral annuloplasty in 4 cases, mitral valvuloplasty in 7 cases and mitral commissurotomy in 2 cases 7. The operative mortality was 7.9%, and 5 years actuarial survival rate was 89%.

• 대한전기학회논문지
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• 제43권2호
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• pp.312-317
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• 1994

We studied the fabrication and electrical characteristics of high voltage hydrogenerated amorphous silicon thin film transistor using plasma enchanced chemical vapor deposition(PECVD). The device shows 2500${\AA}$ SiOS12T, 400-1500${\AA}$ a-Si tickness, 350V output voltage and 9.55${\times}$10S04T average on/off current ratio. We found that the leakage current of high voltage TFT occurred 0-70V drain voltage. As the leakage current depend on the a-Si thickness, the leakage current of high voltage TFT decreased by reduction of the a-Si thickness.

• ETRI Journal
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• 제23권3호
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• pp.121-128
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• 2001

In this paper, the theoretical as well as experimental results of BER characteristics of three different modulation schemes, ASK, FSK and BPSK, in a multi-path Rician channel are addressed. These BER characteristics are analyzed as a function of $E_b/N_o$ and the power ratio of the line of sight (LOS) component to the Rayleigh scattered component. The theoretical as well as computer simulation results shows the ASK is the most suitable modulation scheme for the dedicated short range communication (DSRC) in terms of implemental cost and system complexity. The decision feedback equalizer is proved to be very effective in canceling the multi-path interference in the DSRC channel environment. The simulation result of the equalized ASK, reveals the performance enhancement achievable with decision feedback (DFE) equalizer for the first generation DSRC system. The multi-ray DSRC channel model is also provided to predict the received carrier power and fluctuation, which are quite dependent on the surroundings of a cell.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.279-283
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• 1998

The electron swarm parameters in the$CF_4$(O.l%, 5%)+Ar mixtures are measured by time of flight method over the E/N(Td) range from 10 to 300LTdl. A two-term approximation of the Boltzmann equation analysis and Monte Carlo simulation have been also used to study electron transport coefficients. We have calculated W, NDL, NDT, $\alpha$ and the limiting breakdown electric field to gas mixtures ratio in pure $CF_4$ gas and$CF_4+Ar$ mixtures. The measured results and the calculated results have been compared each other paper.

• 한국환경과학회지
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• 제24권8호
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• pp.1015-1021
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• 2015

In order to establish the design parameters of adsorption for arsenic compounds with hydrotalcite including chlorine ion, the basic properties of adsorption and desorption as well as the oxidation of As (III) were examined in batch tests. The maximum adsorption capacities of arsenite and arsenate were 6.2 mg-As(III)/g and 103 mg-As (V)/g, respectively. Although 80.4% of maximum desorption was shown in 20% NaOH solution, 5~10% of NaOH was recommended considering operating benefits, where the proper condition of the desorption was in the range of 73% to 80%. The most suitable desorption condition was in the combination of NaCl (10~20%) and NaOH (5~10%). Within 2 minutes, As (III) was easily oxidized to As (V) with 0.0001 N KMnO4, where the maximum oxidization ratio was shown to 98.9%.

• 대한산업공학회지
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• 제29권3호
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• pp.222-229
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• 2003

In this paper, we address a layout design problem, PTN[2], for determining an appropriate 2-class-based dedicated storage layout in a class of unit load storage systems. Our strong conjecture is that PTNI2] is NP-hard. Restricting PTN[2], we provide three solvable cases of PTN[2] in which an optimal solution to the solvable cases is one of the partitions based on the PAI(product activity index)-nonincreasing ordering. However, we show with a counterexample that a solution based on the PAI-non increasing ordering does not always give an optimal solution to PTN[2]. Utilizing the derived properties, we construct an effective heuristic algorithm for solving PTN[2] based on a PAI-non increasing ordering with performance ratio bound. Our algorithm with O($n^2$) is effective in the sense that it guarantees a better class-based storage layout than a randomized storage layout in terms of the expected single command travel time.