• 유기물자원화
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• 제2권2호
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• pp.39-51
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• 1994

육계분을 pile의 내부온도 peak를 조절하여(조절 무, $70^{\circ}C$이하, $60^{\circ}C$ 이하 composting 처리시 공정기간에 걸친 물리.화학적인 성상 변화를 고찰하였다. Composting 에 이용된 구조물의 크기는 $1.0{\times}1.0{\times}1.2m$였다. 육계분은 공정 개시후 5~6주 경과시 암모니아취가 없고, 왕겨 크기의 입자로 분해된, 연한 갈색의 최종 생산물로 전환되었다. Compost 의 내부온도는 공정 개시후 3~4일경에 peak에 도달하였고, 이 후 서서히 감소하였다. 8주 경과시의 Compost 의 최종 함수율은 26.5% 였으며, pH는 9.0~9.1, C/N ratio는 14.0~14.3의 범위를 보였다. C/N ratio 의 증가는 N의 손실이 주 요인이었다. 최초 중량과 비교할 때, 공정 후 8주 경과시의 총 중량은 평균 38.8%, 건물 중량은 평균 64.1%, 유기물 중량은 평균 34.8% 정도였다. 계분 compost 의 함수율, pH, C/N ratio, 총 중량, 건물 중량, 유기물 중량은 내부온도 조절에 의하여 영향을 받지 않았다. 육계분 compost 는 공정 개시 후 5~6주 경과시에 물리.화학적 변화가 매우 적은 물질로 전환되었으며, 공정상의 N 손실을 사전 방지하여 composting 효율을 향상시키는 방안이 고려되어져야 할 것으로 사료되었다.

• 한국식품영양학회지
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• 제27권3호
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• pp.414-420
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• 2014

This study was performed to increase the yield and to reduce the processing times for the preparation to improve the productivity and quality of rice jochung, a traditional food in Korea. In order to evaluate the quality characteristics and yield of jochung, the viscosity, color value, mineral contents and the sensory evaluation were measured. Jochung is prepared from steamed rice (STR), wet-milled rice flour (WRF) and dry-milled rice flour (DRF) by processing methods of rice and reacting times (6 hours or 13 hours) of liquefaction and saccharification. There is commonly added liquefying enzyme for rice liquefaction (0.4%/10 kg rice, at $85{\sim}90^{\circ}C$ for 1 hour or 4 hours) and saccharogenic enzyme with malt (2.5% or 4.5%/10 kg rice, at $56{\sim}60^{\circ}C$ for 5 hours or 9 hours). The inner structural properties of WRF showed the more distinct shape regular structure of uncombined starch particles but the DRF closely maintained particles of rice flour observed by SEM. If processing times for liquefation and saccharification were reduced from 13 hours to 6 hours, the yield of jochungs prepared with WRF increased 8%, the DRF 7%, and the STR 3% respectively and the sensory evaluation as well as color values and overall desirability received high scores. The viscosity, color a and b values of jochung processed with WRF for 6 hours were lower than that processed for 13 hours. The viscosity and color a, b value and Ca content were decreased in the jochung processed with WRF or DRF for 6 hours, but Mg, P and K were increased than that of STR. Jochung processed by 0.4% liquefying enzyme and 2.5% malt with WRF for 6 hours will increase the yield, save manufacturing times and costs and will thereby enable cost-effective techniques.

• 한국표면공학회지
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• 제28권1호
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• pp.55-63
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• 1995

Alkaline solutions such as $NH_4$OH, choline and TMAH (($CH_3$)$_4$NOH) have been introduced in semiconductor wet processing of silicon wafers to control ionic and particulate impurities following etching in acidic solutions. These chemicals usually mixed with hydrogen peroxide and/or surfactants to control the etch rate of silicon. The highest etch rate was observed in $NH_4$OH solutions at a pH in alkaline solutions. It indicates that the etch rate depends on the content of $OH^{-}$ as well as cations of alkaline solutions. STM/AFM techniques were used to characterize the effect of alkaline solutions on silicon surface roughness. In SC1 (mixture of $NH_4$OH : $H_2$$O_2$ : $H_2$O) solutions, the reduction of the ammonium hydroxide proportion from 1 to 0.1 decreased the surface roughness ($R_{rms}$) from 6.4 to $0.8\AA$. The addition of $H_2$$O_2$ and surfactants to choline and TMAH reduced the values of $R_{p-v}$ and $R_{rms}$ significantly. $H_2$$_O2$ and surfactants added in alkaline solutions passivate bare silicon surfaces by the oxidation and adsorption, respectively. The passivation of surfaces in alkaline solutions resulted in lower etch rate of silicon thereby provided smoother surfaces.s.ces.s.

• 대한전기학회논문지:시스템및제어부문D
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• 제55권12호
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• pp.550-557
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• 2006

This paper proposes a dry-type surface myoelectric sensor for the myoelectric hand prosthesis. The designed surface myoelectric sensor is composed of skin interface and processing circuits. The skin interface has one reference and two input electrodes, and the reference electrode is located in the center of two input electrodes. In this paper is proposed two types of sensors with the circle- and bar-shaped reference electrode, but all input electrodes are the bar-shaped. The metal material of the electrodes is the stainless steel (SUS440) that endures sweat and wet conditions. Considering the conduction velocity and the median frequency of the myoelectric signal, the inter-electrode distance (IED) between two input electrodes as 18mm, 20mm, and 22mm is selected. The signal processing circuit consists of a differential amplifier with a band pass filter, a band rejection filter for rejecting 60Hz power-line noise, amplifiers, and a mean absolute value(MAV) circuit. Using SUS440, six prototype skin interface with different reference electrode shape and IED is fabricated, and their output characteristics are evaluated by output signal obtained from the forearm of a healthy subject. The experimental results show that the skin interface with parallel bar shape and the 18mm IED has a good output characteristics. The fabricated dry-type surface myoelectric sensor is evaluated for the upper-limb amputee.

• 한국환경과학회지
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• 제23권7호
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• pp.1269-1275
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• 2014

Ecotoxicity assessments with the physiochemical water quality items and the bioassay test using Daphnia magna were conducted for 18 selected effluents of 6 industrial types (metal processing, petroleum refining, synthetic textile manufacturing, plating, alcohol beverage manufacturing, inorganic compound manufacturing) being detected toxicity from industrial effluent in Ulsan city, and the interrelationship between total toxic unit (${\Sigma}TU$) and concentrations of Water Quality Conservation Act in Korea were investigated. The average toxic unit(TU) of effluents for 6 industrial types displayed the following ascending order: petroleum refining (0.2) < synthetic textile manufacturing (0.6) < alcohol beverage manufacturing (0.9) < metal processing (1.3) ${\leq}$ inorganic compound manufacturing (1.3) < plating (3.0). These values were less than effluent permission standard. Based on the result of substances causing ecotoxicity, the correlation analysis was not easy because most of heavy metals were not detected or were less than effluent permission standard. Toxicological assessment of industrial effluent was suitable for the evaluation of the mixture toxicity for pollutant. The whole effluent toxicity test using a variety of species was needed for the evaluation of industrial wastewater.

• 한국기계가공학회지
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• 제12권2호
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• pp.20-26
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• 2013

This study focused on how it affects the surface roughness of work piece in cutting SCM415 steel, widely used steel in industry, by TiCN and TiN tools. Following conclusion was drawn from several experiments. The surface roughness of heat treated workpiece was better than that of non heat-treated materials. Moreover, the roughness of surface roughness(Ra 0.25) on feeding rate of 0.05 was better when it was in wet process, rather than dry process. As the feeding rate increases, TiCN coating tool shows better roughness of surface than TiN tool. Also, in heated treatment, TiCN coating tool shows the least straightness dimension deviation at feeding rate of 0.05, 0.15mm/rev, and concave-like R shape appears by the feeding rate orders of 0.05, 0.15, 0.1, 0.125 and 0.075mm/rev.

• 한국구조물진단유지관리공학회 논문집
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• 제17권5호
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• pp.113-121
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• 2013

본 연구의 복합 센서의 상태 판정 알고리즘을 적용한 노면결빙 예측 및 강설 감지 시스템은 기존 단일 센서 만을 이용하던 기존 방식에서 벗어나, 접촉식/비접촉식 센서 및 적외선 카메라를 통합 운영하여 분사 시스템의 분사 시기와 융설액 분사량을 최적 제어한다. 시스템에 적용된 상태 판정 알고리즘은 취득한 온/습도 데이터와 수분 감지 데이터, 관측된 도로 영상의 영상처리기술 등을 이용하여 노면결빙 위험상태와 강설 상태 뿐만 아니라 강설 강도까지 구분하여 판정을 수행한다. 제작된 시스템의 현장 적용 실험에서는 강설 상태 감지율 89% 습윤 상태 감지율 94%의 우수한 판정 결과와 신뢰성을 검증하였다.

• Elastomers and Composites
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• 제56권3호
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• pp.152-163
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• 2021

Liquid butadiene rubber (LqBR) is used as a processing aid and plays a vital role in the manufacture of high-performance tire tread compounds. In this study, center-functionalized LqBR (C-LqBR) was polymerized with different vinyl content via anionic polymerization. The effects of the vinyl content on the properties of the compounds were investigated by partially replacing the treated distillate aromatic extract (TDAE) oil with C-LqBR in silica-filled rubber compounds. C-LqBR compounds showed a low Payne effect and Mooney viscosity regardless of the vinyl content, because of improved silica dispersion due to the ethoxysilyl group. As the vinyl content of C-LqBR increased, the optimum cure time (t₉₀) increased owing to a decrease in the number of allylic hydrogen. Moreover, the glass transition temperature (T_g) of the compound increased, and snow traction and abrasion resistance performance decreased, whereas wet grip improved. The energy loss characteristics revealed that the hysteresis attributed to the free chain ends of C-LqBR was dominant.

• 대한건축학회논문집:구조계
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• 제35권6호
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• pp.121-128
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• 2019

There is a big move to build zero-energy buildings in the form of passive houses that reduce energy waste worldwide. Korea has set a goal of reducing its greenhouse gas emissions by 37% by 2030 through the activation of green buildings, such as strengthening the energy levels of new buildings and improving the energy efficiency of existing buildings. The use of insulation with high insulation performance is one of the key technologies to realize this, and vacuum insulation is the next generation insulation that blocks the energy flow of the building. In this study, we measured the bonding structure of dry and wet processing glass fiber core materials and compared the insulation performance of vacuum insulation panel. In addition, the insulation performance of vacuum insulation panel was measured according to the thickness of the laminated core. It can be confirmed that the lamination structure of the core and the lamination thickness are important factors for the heat insulating performance of the vacuum insulating panel.

• The Plant Pathology Journal
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• 제34권5호
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• pp.356-366
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• 2018

The red flour beetle, Tribolium castaneum, is one of the most common and economically important pests of stored cereal products worldwide. Furthermore, these beetles can act as vectors for several fungal post-harvest diseases. In this study, we collected T. castaneum from 49 rice processing complexes (RPCs) nationwide during 2016-2017 and identified contaminating fungal species on the surface of the beetles. Five beetles from each region were placed on potato dextrose agar media or Fusarium selection media after wet processing with 100% relative humidity at $27^{\circ}C$ for one week. A total of 142 fungal isolates were thus collected. By sequence analysis of the internal transcribed spacer region, 23 fungal genera including one unidentified taxon were found to be associated with T. castaneum. The genus Aspergillus spp. (28.9%) was the most frequently present, followed by Cladosporium spp. (12.0%), Hyphopichia burtonii (9.2%), Penicillium spp. (8.5%), Mucor spp. (6.3%), Rhizopus spp. (5.6%), Cephaliophora spp. (3.5%), Alternaria alternata (2.8%) and Monascus sp. (2.8%). Less commonly identified were genera Fusarium, Nigrospora, Beauveria, Chaetomium, Coprinellus, Irpex, Lichtheimia, Trichoderma, Byssochlamys, Cochliobolus, Cunninghamella, Mortierella, Polyporales, Rhizomucor and Talaromyces. Among the isolates, two known mycotoxin-producing fungi, Aspergillus flavus and Fusarium spp. were also identified. This result is consistent with previous studies that surveyed fungal and mycotoxin contamination in rice from RPCs. Our study indicates that the storage pest, T. castaneum, would play an important role in spreading fungal contaminants and consequently increasing mycotoxin contamination in stored rice.