• 한국자동차공학회논문집
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• 제16권4호
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• pp.165-172
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• 2008

Urea-SCR, the selective catalytic reduction using urea as reducing agent, has been investigated for about 10 years in detail and today is a well established technique for deNOx of stationary diesel engines. In the case of the SCR-catalyst a non-uniform velocity and $NH_3$ profile will cause an inhomogeneous conversion of the reducing agent $NH_3$, resulting in a local breakthrough of $NH_3$ or increasing NOx emissions. Therefore, this work investigates the effect of flow and $NH_3$ non-uniformities on the deNOx performance and $NH_3$ slip in a Urea-SCR exhaust system. From the results of this study, it is found that flow and $NH_3$ distribution within SCR monolith is strongly related with deNOx performance of SCR catalyst. It is also found that multi-hole injector shows better $NH_3$ uniformity at the face of SCR monolith face than one hole injector.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 추계학술대회
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• pp.102-102
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• 2019

Soybean curd residue (SCR), known as a major waste product of soybean processing, is the water-insoluble fraction which is removed by filtration during soymilk production. For these reasons, SCR was usually considered as food waste. SCR might have a good potential as a functional food material, value-added processing and utilization. SCR contains high-quality protein and consists of a good source of nutrients, including protein, oil, dietary fiber, minerals, along with un-specified monosaccharides and oligosaccharides. Also, SCR might be a potential source of low cost protein for human consumption. However, SCR could be a source of bacterial contamination when during food processing. This study was aimed to investigate antibacterial capacity of natural product through detecting relationship between SCR and microbial. We isolated five bacterial strains from SCR and elucidated antibacterial activity of nature medicines to extend storage capacity of food made with SCR. Thus, the extract which showed antibacterial effects in Corynebacterium calloonae and Raoultella amithinolytica is a combination of seven kinds of extracts: Glycyrrhiza uralensis, Cudrania tricuspidata, Salvia miltiorrhiza Bunge, blueberry, Acorus gramineus, Ginkgo biloba L., Camellia sinensis. This study suggested that antibacterial activities of natural medicines could be used for extension of storage capacity in SCR-contained food.

• 전기의세계
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• 제23권6호
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• pp.56-59
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• 1974

It is well-known that the anode circuit of SCR has the current controlled negative resistance characteristic. Recently the present auther has shown that the gate circuit of SCR has the voltage controlled negative resistance characteristic for the constant anode voltage. It is shown of the equivalent model to SCR(when conducting) the voltage controlled negative resistance characteristic for gate circuit. And it is possible to make SCR gate oscillators with their desired characteristic for illustration.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.10-10
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• 2010

ESD (Electrostatic Discharge) phenomenon occurs in everywhere and especially it damages to semiconductor devices. For ESD protection, there are some devices such as diode, GGNMOS (Gate-Grounded NMOS), SCR (Silicon-Controlled Rectifier), etc. Among them, diode and GGNMOS are usually chosen because of their small size, even though SCR has greater current capability than GGNMOS. In this paper, a novel SCR is proposed on the SOI (Silicon-On-Insulator) structure which has $1{\mu}m$ film thickness. In order to design and confirm the proposed SCR, TSUPREM4 and MEDICI simulators are used, respectively. According to the simulation result, although the proposed SCR has more compact size, it's electrical performance is better than electrical characteristics of conventional GGNMOS.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.30-34
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• 1997

This paper Describe a modelling method for SCR(selective Catalytic reduction) system in refuse incineration plant. We consider the SCR system as a single input single output system. For modelling the SCR system, an auto regressive exogeneous(ARX) modelling method is used. In this case, we should design the white noise input for modelling and put it on the system as an input (.NH/sap2/.), and taken an outlet NOx as an output. From these two relations, we design the ARX model with 45 second delay time and transform to discrete system with 0.5 sampling time. Using the obtained SCR model, we simulate the SCR system to reduce the outlet NOx content by a conventional PID control method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 B
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• pp.1333-1335
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• 2000

In order to turn on the SCR gate, trigger signal source have to provide appropriate gate current and voltage under the gate rating based on the characteristic of SCR, the nature of load and power. It will be essential design factors such as trigger source impedance, trigger signal occurring, signal time width and turn off conditions. Also minimum gate trigger current is changed with the deterioration of SCR. SCR, which is needed large gate trigger current absolutely, is very important for SCR characteristic test because it causes unstable output in the misfile or makes a trouble to pulse trigger circuits. This paper shows scheme to test the performance of SCR with the precision analyzing mechanism and the changing trend of minimum gate current under the trigger conditions.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.1199-1201
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• 2004

When The temperature of the joining of SCR rises major changes of characteristics are increase of leakage current, decrease of break-down voltage, and increase of turn off time. Because these changes promote the inferiority of SCR it(SCR) will get out of control and its life time will be shortened and finally it will be destroyed. In this paper, we will measure the changes of the characteristics in accordance with a rise in temperature. On the basis of the result we will find out the appropriate time to change SCR and we will use the result for the maintenance of SCR and increase of reliability of SCR.

• 공업화학
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• 제17권4호
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• pp.414-419
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• 2006

연소 배기가스 중의 수분, 탄화수소 및 CO가 저온 플라즈마 및 $NH_{3}$ SCR (Selective Catalytic Reduction)공정이 복합된 탈질공정에 미치는 영향에 대한 연구가 수행되었다. 실험결과 일반적인 SCR 반응에 비해 매우 빠른 반응속도를 갖는 fast SCR 반응은 $150{\sim}200^{\circ}C$의 저온조건에서 탈질율의 상승을 가져다주지만, 처리가스 중에 탄화수소가 있는 경우 fast SCR 반응의 역할이 상당히 감소되는 것을 확인할 수 있었다. 이는 저온 플라즈마 반응기에서 부분산화반응을 통해 탄화수소 중 일부가 알데히드로 전환되며, 알데히드는 fast SCR 반응에 있어 중요한 변수인 $NO_{2}/NO_{x}$ 비율에 영향을 주기 때문인 것으로 설명되었다. 한편, 수분 및 CO가 fast SCR 반응에 미치는 영향은 탄화수소에 비해 상대적으로 적음을 확인할 수 있었다.

• Preventive Nutrition and Food Science
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• 제9권2호
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• pp.138-143
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• 2004

Soybean curd residues (SCR) obtained from hot and cold manufacturing processes were fermented by indigenous microorganisms, Lactobacillus rhamnosus LS and Bacillus firmus NA-l for 15 h at 37$^{\circ}C$. The pH, acidity, viable cell counts, and tyrosine content were evaluated in samples with variations in sugar, starter and type of SCR. The raw Doowon SCR (D-SCR, cold-processed) fermented by indigenous microorganism had a 0.9% acidity and 6.7 ${\times}$ 10$^{7}$ CFU/g viable cell counts, compared with the 0.11 % acidity and 6.7 ${\times}$ 10$^{6}$ CFU/g viable cell counts of raw fermented Pulmuwon SCR (P-SCR, hot-processed). After fermentation of raw P-SCR with 1 % glucose and 1 % L. rhamnosus LS starter, the viable cell counts, tyrosine content and acidity were 4.7 ${\times}$ 10$^{8}$ CFU/g, 16.3 mg% and 0.9%, respectively. In addition, the raw P-SCR fermented with Bacillus firmus NA-l as co-starter had a 0.45% acidity, 2.4 ${\times}$ 10$^{8}$ CFU/g lactic acid bacteria, and 3.3 ${\times}$ 10$^{6}$ CFU/g Bacillus sp. In particular, the tyrosine content was increased 5 fold. The drying of fermented SCR was completed by hot-air drying (5$0^{\circ}C$) within 12 h; the dried P-SCR and D-SCR had 1.8 ${\times}$ 10$^{7}$ CFU/g and 5.3 ${\times}$ 10$^{6}$ CFU/g viable cell counts, respectively. The concentrate of methanol extract from fermented D-SCR inhibited the initial cell growth of E. coli, Staphylococcus aureus and Pseudomonas aeruginosa in liquid culture.

• 해양환경안전학회지
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• 제27권2호
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• pp.355-362
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• 2021

L.P SCR의 촉매 반응을 위해 선박의 발전기용 4행정 디젤엔진의 배기가스 온도를 높게 설계 할 수밖에 없었다. 본 연구의 목적은 밸브개폐시기와 연료분사시기를 조정을 통한 배기가스의 온도 감소가 L.P SCR의 운전조건을 만족시키고 고온으로 인한 발전기 엔진의 사고를 예방하기 위함이었다. 배기가스 온도를 하강시키기 위해 캠샤프트의 각도를 조정하고 연료분사펌프의 Shim을 추가하였다. 그 결과 최대폭발압력은 12.8 bar 증가하였고 터보차저 출구온도 평균값은 13.3 ℃ 하강하였다. 터보차저 출구에서 SCR 입구까지의 열손실을 감안하더라도 L.P SCR 운전조건인 SCR 챔버 입구 온도인 290 ℃를 만족하였다. 배기가스 온도 하강을 통해 디젤발전기의 안전운전이 가능하게 한 연구였다.