• 한국토양비료학회지
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• 제45권2호
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• pp.248-252
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• 2012

본 연구는 공시 수생식물체 퇴비화 과정 중 산소 소비량과 소비패턴을 조사하기 위하여 식물이 고사된 11월에 수확한 갈대, 부들, 줄을 사용하여 퇴비화를 제조하였다. 수생식물체별 퇴비화 과정중 산소소비량을 조사한 결과 모든 수생식물의 퇴비화조에서 퇴비화 초기에 누적산소소비량이 급격하게 증가하여 약 15일째에 들어서 누적산소소비량의 증가가 둔화되는 경향이었다. 각각의 수생식물별로 누적산소 소비량은 초기에는 비슷한 소비량을 보이나 부들 > 줄 > 갈대 순으로 나타났다. 수생식물체별 퇴비화 과정중 온도변화는 퇴비화가 진행되면서 초기에 급격하게 증가된 후 서서히 감소되어서 약 $30{\sim}40^{\circ}C$ 정도로 안정화 되었다. 각 수생식물체의 퇴비화에서 최고온도까지 도달하는데 걸린 기간은 갈대 (7일) > 부들 (10일) > 줄 (11일) 순으로 나타났고, 퇴비화조 최고온도는 걸린 기간과 반대로 줄 ($72.2^{\circ}C$) > 부들($70.2^{\circ}C$) > 갈대 ($66.5^{\circ}C$) 순으로 나타났다. 최고온도 도달시까지 소비된 산소량은 부들 $12,485mg\;O_2\;kg^{-1}$ > 줄 $12,400mg\;O_2\;kg^{-1}$ > 갈대 $9,340mg\;O_2\;kg^{-1}$ 순으로 나타났는데 이는 각각의 식물체별 비중과 통기성에 따른 것으로 판단된다. 본 연구에서 제조한 수생식물을 이용한 퇴비는 유기물함량이 39.5~44.8%로 부산물비료 공정규격의 퇴비의 규격 50% 이상에 미치지 못하였으나 함유할 수 있는 유해 성분(As, Cd, Cu, Cr, Hg, Ni, Pb 및 Zn) 함량이 규격 이하로 적합하였고, 그 밖의 규격에서 염분(NaCl) 함량 0.01%, 수분함량 29.6~35.6% 및 유기물대 질소의 비 27.93~32.94로 퇴비 규격에 적합하였다.

• 한국주조공학회지
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• 제20권5호
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• pp.323-329
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• 2000

The HSS consists of hard carbide and matrix of martensite, and so its characteristics of wear resistance, fracture resistance, and surface roughness are good. This study was undertaken to investigate the influence of Nb and V and manufacturing conditions on microstructural behaviors and characteristics in the HSS cylindrical specimens(90 $mm^{O.D.}$ ${\times}$ 60 $mm^{I.D.}$ ${\times}$ 50 $mm^H$) manufactured using VCC(Vertical Centrifugal Casting). In the specimen of Fe-2C-6Cr-1.5W-3Mo-4V alloy, the amount of MC carbide was increased and $M_7C_3$ carbide was decreased with the increase of V and Nb contents. The primary VC carbide was formed and followed by the rod-type eutectic MC carbide was formed in the cell boundary in 9%V added specimen. MC carbide was increased, and $M_7C_3$ carbide was decreased with the addition of Nb content. In the specimen containing more than 3%Nb, primary NbC carbide was formed within the cell of matrix. With increase in rpm, cell and carbides became fine, and amount of carbide $M_7C_3$ was decreased due to increase in cooling rate.

• 한국가정과학회지
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• 제6권1호
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• pp.27-34
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• 2003

We investigated the bacterial and chemical retting conditions of ramie grown in Hansan. Bacterial retting was done in troughs at a temperature of 30${\pm}$2$^{\circ}C$ for 1, 2, 3, 4, 5, 6 and 10 days. Chemical retting(CR) was done at the different conditions using sodium silicate (Na$_2$SiO$_3$), sodium carbonate(Na$_2$CO$_3$) and sodium hydroxide(NaOH) as alkali solutions. The retting solution was boiled during 1. 2, 4 and 6 hours respectively at the different concentration(0.5, 2.0, 4.0, 6.0. 8.0 %) with decorticated ramie stems submerged in it. The treated ramie was then rinsing with running tap water thoroughly, which was further soaker in 0.5% acetic acid (v/v) solution for three minutes and washed thoroughly with distilled water. Finally ramie was dried for 2 hours in vacuum oven at 100 $^{\circ}C$. To know change of ramie fiber characteristics retted at the different conditions, weight loss, fiber bundle strength were tested and color, texture, luster etc. were also sensually evaluated. The results were as follows. $.$ Weight loss of ramie retted in each alkali solutions were about 10%, 20% and 30% in sodium silicate, sodium carbonate and sodium hydroxide, respectively. $.$ Chemical retting was faster than bacterial retting, but the color of chemically retted ramies were worse than that of bacterially retted ramies. $.$ The combination of bacterial and chemical processing showed some merits. A combination of either 2 or 3 days of bacterial and then chemical retting might provide the best quality ramie. $.$ Ramie fiber became cottonized ramie when retted in 8% NaOH solution for 6-8hours.

• Asian Pacific Journal of Cancer Prevention
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• 제13권11호
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• pp.5741-5746
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• 2012

Aim: Although preoperative chemoradiatherapy (CRT) has proven its benefits in terms of decreased toxicity, there is still a considerable amount of cases that do not receive postoperative CRT. Oncologists at different geographic locations still need to know the long-term effects of this treatment in order to manage patients successfully. The current paper reports on long-term quality of life (QOL) and late side effects after adjuvant CRT in rectal cancer patients from 5 centers in Anatolia. Methods: Rectal cancer patients treated with postoperative CRT with minimum 1-year follow-up and were in complete remission, were evaluated according to RTOG and LENT-SOMA scales. They were also asked to complete Turkish version of EORTC QLQ-C30 questionnaire and the CR-38 module. Each center participated with the required clinical data. Results: Two hundred and thirty patients with median age of 55 years participated and completed the study. Median follow-up time was 5 years. All patients received RT concomitant with chemotherapy. Common parameters that both increased functional health scales and yielded better symptom scores were long term interval after treatment and sphincter-saving surgery. In addition, surgery type and follow-up time were determined to be predictors of QOL scores and late toxicity grade. Conclusion: Postoperative CRT was found to have a great impact on the long term QOL and side effects in rectal cancer survivors. The factors that adversely affect these are abdominoperineal resection and shorter interval. The findings may encourage life-long follow-up and cooperation with patients, which should be mentioned during the initial counseling.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.245-245
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• 2015

Cu(In,Ga)Se2 (CIGS) 박막 태양전지는 높은 효율과 낮은 제조비용, 높은 신뢰성으로 인해 박막 태양전지 중 가장 각광받고 있다. 특히 유리기판 대신 가볍고 유연한 철강소재나 플라스틱 소재를 이용하여 발전분야 외에 건물일체형, 수송용, 휴대용등 다양한 분야에 적용이 가능하다. 이러한 유연 기판을 이용한 CIGS 태양전지의 개발을 위해서는 기판의 특성에 따른 다양한 공정개발이 선행되어야 한다. 특히 CIGS 태양전지에서는 Na의 역할이 매우 중요한데 유연기판의 경우 이러한 Na이 없을 뿐만 아니라 철강기판의 경우 Fe, Ni, Cr등의 불순물이 확산되어 흡수층의 특성을 저하시켜 효율을 감소시킨다. 따라서 이러한 철강 기판의 경우 불순물의 확산을 방지하는 확산방지막이 필수적이다. 또한 플라스틱기판의 경우 내열성이 낮아 저온에서 공정을 진행해야하는 단점이 있다. 이러한 유연기판의 특성을 고려하여 본 연구에서는 유연기판으로 STS 430 stainless steel과 poly-imide를 이용하여 특성 개선을 진행하였다. 먼저 stainless steel과 Poly-imide, soda-lime glass, coning glass의 기판을 이용하여 기판에 따른 흡수층의 특성을 비교 분석하였으며 stainless steel 기판을 이용하여 확산 방지막의 유무 및 두께에 따른 흡수층 및 소자의 특성을 분석하였다. 이때 확산 방지막은 기존 TCO 공정에서 사용되는 i-ZnO를 사용하였으며 RF sputter를 이용하여 50~200nm로 두께를 달리하며 특성 비교를 실시하였다. 이때 효율은 확산방지막을 적용하지 않았을 때 약 5.9%에서 확산 방지막 적용시 약 10.6%로 증가하였다. 또한 poly-imide 기판을 이용하여 $400^{\circ}C$이하에서 흡수층을 제조하여 특성평가를 진행하였으며 소자 제조 후 효율은 약 12.2%를 달성하였다. 모든 흡수층은 Co-Evaporation 방법을 이용하여 제조하였으며 제조된 흡수층은 SEM, XRF, XRD, GD-OES, PL, Raman등을 이용하여 분석하였으며 그 외 일반적인 방법을 이용하여 Mo, CdS, TCO, Al grid를 제조하였다. AR 코팅은 제외 하였으며 제조된 소자는 솔라 시뮬레이터를 이용하여 효율 특성 분석을 실시하였으며 Q.E. 분석을 실시하였다.

• 한국세라믹학회지
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• 제45권9호
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• pp.549-555
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• 2008

The thermal barrier coating must withstand erosion when subjected to flowing gas and should also maintain good stability and mechanical properties while it must also protect the turbine component from high temperature, hot corrosion, creep, and oxidation during operation. In this study we investigated the influence of subsurface layer, $Al_2O_3$ or NiCrCoAIY bond coat layer, on the indentation damage behavior of YSZ thermal barrier coating layers deposited by electron beam physical vapor deposition (EB-PVD). The bond coat is deposited using different process such as air plasma spray (APS) or spray of high velocity oxygen fuel (HVOF) and the thickness is varied. Hertzian indentation technique is used to induce micro damages on the coated layer. The stress-strain behaviors are characterized by results of the indentation tests.

• 한국초전도ㆍ저온공학회논문지
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• 제6권3호
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• pp.50-55
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• 2004

We fabricated and tested a resistive type superconducting fault current limiter (SFCL) of three-phase 6.6 $kV_{rms}/200 A_{rms}$ rating based on YBCO thin films grown on sapphire substrates with a diameter of 4 inches, Short circuit tests were carried out at a accredited test facility for single line-to- ground faults, phase-to-phase faults and three-phase faults, Each phase of the SFCL was composed of 8${\times}$6 elements connected in series and parallel respectively. Each element was designed to have the rated voltage of 600 $V_{rms}$. A NiCr shunt resistor of 23 Ω was connected to each element for simultaneous quenches. Firstly, single phase-to-ground fault tests were carried out. The SFCL successfully developed the impedance in the circuit within 0.12 msec after fault and controlled the fault current of 10 $kA_{rms} below 816 A_{peak}$ at the first half cycle. In addition, in case of phase-to-phase fault and three- phase fault test. simultaneous quenches among the SFCLs of the phases successfully accomplished. In conclusion. the SFCL showed excellent performance of current limitation upon fault and stable operation regardless of the amplitude of fault currents.

• 복식
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• 제56권1호
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• pp.97-105
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• 2006

The dyeability and antibacterial activity of fabrics dyed with lavender extract were analyzed. The results obtained are as follows. The surface color of all the dyed fabrics was tinged with green or yellow of a slight red tint. In the test results of dyeing colorfastness, the colorfastness to sunlight of the dyed fabrics which is both not treated with a mordant and treated with a K2Cr2O7 mordant was excellent with 4th grade of colorfastness. The others showed below 2nd grade. The colorfastness to laundry showed, as most of dyed fabrics were 4th-5th grade, relatively excellent results. The colorfastness to perspiration showed different results respectively according to the kind of both dyed fabrics and mordants. The colorfastness to crocking of the dyed both cotton and silk fabrics showed the excellent result of 4th-5th grade. The colorfastness to dry cleaning of all the dyed fabrics was excellent with 4th-5th grade. In the test results of antibiosis, the dyed fabrics of both cotton and silk didn't show the significant decrease rate for the fungus called Klebsiella pneumoniae. For the fungus called Staphylococcus aureus, the dyed cotton fabric showed the decrease rate of $98\%$ and the dyed silk fabric showed the decrease rate of $50\%$. For the fungus called Chaetomium globosum, the dyed fabric of cotton didn't show the significant antibacterial efficacy, but the dyed fabric of silk showed the significant antibacterial efficacy for the mold fungus called Aspergillus niger.

• Journal of Welding and Joining
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• 제33권4호
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• pp.30-36
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• 2015

Austenite stainless steel(SA213-TP347H) has widely been used for the superheater & reheater tube in USC(ultra-supercritica) coal boiler because of its high creep rupture strength and anti-oxidation. But recently, the short-term failures have happened frequently in heat affected zone for only 4,000~15,000hours of service. Many investigations have been conducted to understand the failure mechanism. The root cause of failure was comfirmed to "strain induce participation hardening crack" or "reheat cracking". This mechanism often occurred due to weld residual stress and precipitation of the Cr, Nb carbides in the stabilized stainless steel such as TP347H. This paper presents an analysis of failure tube and effect of the sample tubes that conducting stabilizing heat treatment in site after 11,380hours & 16,961hours of service. Visual inspection was performed. In addition, microscopic characteristics was identified by O.M, SEM, and hardness test was carried out to find out the heat treatment effects. Failures seem to happen because of being not conducted stabilizing heat treatment in site. And another cause is inadequate weld parameter such as pass, ampere, voltage, inter-pass temperature. Thus, this paper has the purpose to describe that how to prevent similar failures in those weld-joints.

• Asian-Australasian Journal of Animal Sciences
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• 제23권7호
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• pp.924-930
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• 2010

Ileal and total tract digestibility and nitrogen (N) balance of diets with four different protein sources were determined in growing pigs. The diets were based on rice bran, broken rice and maize meal and contained Tra catfish by-product (CBP), processed using three different methods, and marine fish meal (FM). The CBP diets consisted of the by-product in meal form, ensiled with molasses, and CBP waste water (WWBD). The four diets were fed to four growing pigs fitted with post-valve T-cecum (PVTC) cannulas in a $4{\times}4$ Latin Square design. All experimental diets included $Cr_2O_3$ at 5 g/kg feed as an indigestible marker. The ileal apparent digestibility of organic matter and ether extract was higher on diet WWBD than on the other three diets (p<0.05), and the total tract apparent digestibility was higher on diet WWBD than on the FM diet (p<0.05). The ileal and total tract apparent digestibility of crude protein and amino acids was not significantly different among diets (p>0.05). No significant effects of diet were found on N-retention and N utilization. In conclusion, the catfish by-product meal, ensiled catfish by-product and processing waste water diets and the fish meal diet had similar ileal and total tract apparent digestibility, and similar N utilization in growing pigs.