• Journal of Microbiology and Biotechnology
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• 제15권2호
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• pp.247-253
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• 2005

The bacterial cellulose (BC) production by a wild­strain Acetobacter xylinum BPR2001 and that by its acetan­nonproducing mutant, EPI, were compared in a jar fermentor. EPI produced about $28\%$ less BC than the wild-strain. The apparent difference in the cultivation of the two strains was the viscosity increase in the culture broth that was closely associated with acetan production. Increasing the viscosity of the culture broth of EPI by adding agar led to the formation of relatively small and uniform BC pellets, and BC production consequently became two-fold higher than that in the absence of agar and was almost equal to that by BPR2001. Therefore, acetan has an important role in BC production by inducing physical changes in the culture broth of the wild-type strain.

• Journal of Power Electronics
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• 제2권2호
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• pp.104-111
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• 2002

This paper presents a new hybrid control scheme using Active-Clamped Class-E(ACCE) inverter for the Induction Heating (IH) jar. The proposed hybrid control scheme has characteristics, which acts as class-E inverter at lower switch voltage and ACCE inverter at higher switch voltage than reference voltage of the main switch by feeding back voltage of the switch. The proposedv hybrid control scheme also has advantage of conventional ACCE inverter such as Zero-Voltage-Switch(ZVS) of the main switch and the reduced switch voltage due to clamping cricuit. Moreover, the proposed hybrid control method using ACCE inverter has higher output power than convenional control scheme since ACCE inverter operates like class-E inverter at low input voltage condition. The principles of the proposed control are explained in detail and the validity of the proposed control scheme is verifed through the several interesting simulated and experimental results.

• Journal of Multimedia Information System
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• 제8권1호
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• pp.45-56
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• 2021

This document traces the new technologies development based on a deep classical Hill method improvement. Based on the chaos, this improvement begins with the 256 element body construction, which is to replace the classic ring used by all encryption systems. In order to facilitate the application of algebraic operators on the pixels, two substitution tables will be created, the first represents the discrete logarithm, while the second represents the discrete exponential. At the same time, a large invertible matrix whose structure will be explained in detail will be the subject of the advanced classical Hill technique improvement. To eliminate any linearity, this matrix will be accompanied by dynamic vectors to install an affine transformation. The simulation of a large number of images of different sizes and formats checked by our algorithm ensures the robustness of our method.

• 한국환경과학회지
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• 제19권8호
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• pp.931-940
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• 2010

The Raw water from Deer Creek (DC) reservoir and Little Cottonwood Creek (LCC) reservoir in the Utah, USA were collected for jar test experiments. This study examined the removal of arsenic and turbidity by means of coagulation and flocculation processes using of aluminum sulfate and ferric chloride as coagulants for 13 jar tests. The jar tests were performed to determine the optimal pH range, alum concentration, ferric chloride concentration and polymer concentration for arsenic and turbidity removal. The results showed that a comparison was made between alum and ferric chloride as coagulant. Removal efficiency of arsenic and turbidity for alum (16 mg/L) of up to 79.6% and 90.3% at pH 6.5 respectively were observed. Removal efficiency of arsenic and turbidity for ferric chloride (8 mg/L) of up to 59.5% at pH 8 and 90.6% at pH 8 respectively were observed. Optimum arsenic and turbidity removal for alum dosages were achieved with a 25 mg/L and 16 mg/L respectively. Optimum arsenic and turbidity removal for ferric chloride dosages were achieved with a 20 mg/Land 8 mg/L respectively. In terms of minimizing the arsenic and turbidity levels, the optimum pH ranges were 6.5 and 8for alum and ferric chloride respectively. When a dosage of 2 mg/L of potassium permanganate and 8 mg/L of ferric chloride were employed, potassium permanganate can improve arsenic removal, but not turbidity removal.

• 한국미생물·생명공학회지
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• 제10권2호
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• pp.95-100
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• 1982

절간고구마원료주정폐액을 이용하여 단세포단백질을 생산함과 동시에 폐액의 BOD를 제거할 목적으로 우수효모를 선발하고, 선발된 효모의 배양조건을 검토한 후 3$\ell$ -jar fermenter에 의한 통기 배양을 한 결과 다음과 같은 결론을 얻었다. 폐액을 여과한 여액의 조성은 BOD$_{5}$ 15700ppm, COD 36800ppm, 환원당 3300ppm, 총질소 710ppm, 고형물51800ppm, 조회분390ppm이었다. 우수효모로 선발된 Torulopsis candida FRI YA-15를 $25^{\circ}C$에서 48시간 진탕배양하였을 때, 배양폐액에 대한 균체수율은 3.38g/$\ell$, BOD$_{5}$ 및 COD제거율은 각각 38.9%, 31.8%이었다. T. candida의 최적생육초기 pH는 4.0이었으며, 최적배양온도는 35$^{\circ}C$였다. 설정된 초기PH 및 온도하에서 3$\ell$-jar fermenter를 사용하여 통기량 2vvm, 교반속도 100rpm으로 배양하였을 때, 배양 28시간후에 최대로 생육하였으며, 그 때 배양액에 대한 균체수율은 3.2g/$\ell$였다. 건조균체의 조단백질함량은 47.98%였다.

• 한국산학기술학회논문지
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• 제16권3호
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• pp.2321-2327
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• 2015

본 연구는 급격한 수질변화에 따른 현장 적용에 적합한 응집제를 선정하고, 응집제 별 최적 주입량을 찾기 위해 aluminium sulfate, poly aluminum chloride, poly aluminum silicate chloride를 이용하여 Jar-Test와 Pilot-Test의 검증으로 실험 하였다. 분석 항목은 탁도, TOC, pH로 제거율을 측정하였다. 실험 결과를 바탕으로 PASC의 경우 기존 응집제 인 Alum이나 PAC 보다 최적 주입량 (15 mg/L)이 상대적으로 적었으며, 제거율도 높게 나타남을 확인할 수 있었다. Jar-Test에서는 원수 탁도 3-20 NTU 범위에서 응집제(PASC)의 최적 주입량을 주입하였을 때, 탁도 제거율(80%)과 TOC 제거율(89%)이 가장 높았으며, Pilot-Test에서는 원수 탁도 3.6-27 NTU 범위에서 응집제 최적 주입량을 주입하였을 때 탁도 제거율(82%)과 TOC 제거율(88%)을 확인할 수 있었다. 따라서 본 연구 결과를 바탕으로 응집제의 제거 효과는 원수 탁도와 TOC가 높아질수록 상승하는 경향을 확인할 수 있었다.

• 동아시아식생활학회지
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• 제3권2호
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• pp.1-13
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• 1993

This paper has examined and analyzed the ways of making Jang(Korean soybean sauce), vinegar and liquor in terms of food processes, which are mentioned in sooljip 5 and 6 Food collections of 'Kosa-sibi Jip', an encyclopaedia written in Chinese and published in 1789-the eleventh year of King Jung-jo of Chosun Dynasty. There respestively six items of nine items of and thirty three items of the recipe for making jang, vinegar and liquor, Soybean was a major material for making jang. And wheat flour and ground barley were added. Myun-jang was made from only flour. Dong-kook Jojang Bup(oriental soybean sauce preparation) which is the traditional Korean process for making jang from only soybean is recorded in this book. The cereals used in the nine items of the vinegar making recipe were rice(six times), wheat(twice), barley(three times) and wheat flour(once). And fruits are also used. Rice was most used of all these materials. The cereals used in the thirty three items of the liquor-making recipe were regular rice(50%), sticky rice(42.6%) and wheat flour(7.4%) In particular sticky rice was much used for Yakyee Rhue and Bok-sik Rhue for medications. The ways of processing cereals for liquor-making were Jee-ae-bop : steamed rice(52.9%), Jook:thick gruel with cereal (32.3%), Goo-mung Tuck: doughnut-shaped rice cake(8.8%) and Hin-moo-ree Tuck: shawith peless rice cake(2.9%). The three unique processes are as follows. First, in winter when the process of liquor-making did not go on because the jar was cold, the bottle with hot water in was put in the jar and so the aduquate temperature for liquor-making was maintained. Next, in warming up a small double boiler, they prevented effervescence by hanging down thread. Finally. in warming up in a double boiler, they sealed the mouth-piece of the jar and put a handful of wet rice when the rice was completely cooked, it was thought of as the sign that the process of liquor-making was done.

• 한국식품영양과학회지
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• 제26권1호
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• pp.60-66
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• 1997

Monascus anka가 생산하는 색소는 균체외 적색색소(ERP)와 황색색소(EYP) 그리고 균체내 적색색소(IRP) 와 황색색소(IYP)로 분리되었고 각각의 색소는 특징적인 absorption spectrum을 나타냈다 분리된 4종의 색소의 안정성을 검토한 결과, 암조건, 자외선 그리고 형광하에서는 비교적 안정하였지만 일광하에서는 색소가 급격히 퇴색하는 경향을 나타내 저장시 광차단이 필요함을 알 수 있었다. pH에 대해서는 각 색소가 pH 2.0~12.0 범위에서 비교적 안정하였다. 온도의 영향은 60~8$0^{\circ}C$에서는 비교적 안정하였으나 그 이상의 온도에서는 안정성이 떨어지는 것으로 나타났다. 8종의 유기산 중에 tartaric acid와 citric acid가 홍국색소의 안정성을 저해하는 것으로 나타났고 propionic, formic, acetic, butyric, malonic, malic acid는 비교적 안정하였다. 홍국색소의 변색에 가장 큰 영향을 미치는 금속 이온은 Cu$^{2+}$이었다.

• 한국해양환경ㆍ에너지학회지
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• 제3권1호
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• pp.62-69
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• 2000

본 연구는 담수조류의 대량 번식에 따른 정수장의 여과막 박힘, 어류의 대량폐사 등 각종 피해를 최소화하기 위하여 응집제를 이용한 응집-여과공정을 녹조제거시스템에 적용하기 위한 것이다. 응집-여과 공정에서 최적의 응집상태를 결정하기 위하여 시료로는 낙동강 원수를 사용하였고 Jar test와 실험실용 반응기를 사용하여 알칼리도, 탁도, Chl-a, pH를 측정하였다. 응집시간, 응집제 주입량, 드럼필터 회전속도 그리고 Chl-a는 각각 5min, 5mg/l, 3rpm 그리고 90㎍/l의 조건에서 높은 조류제거율을 보였다. Alum을 사용하였을 때의 조류 및 탁도 평균제거율은 50～60%, 30～50%이었고, PAC는 Chl-a의 제거율이 Alum보다 약 20% 더 좋은 효율을 보였다.

• 제어로봇시스템학회논문지
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• 제3권6호
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• pp.644-651
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• 1997

In the water purification plant, chemicals are injected for quick purification of raw water. It is clear that the amount of chemicals intrinsically depends on water quality such as turbidity, temperature, pH and alkalinity. However, the process of chemical reaction to improve water quality (e.g., turbidity) by chemicals is not yet fully clarified nor quantified. The feedback signal in the process of coagulant dosage, which should be measured (through the sensor of the plant) to compute the appropriate amount of chemicals, is also not available. Most traditional methods focus on judging the conditions of purifying reaction and determine the amounts of chemicals through manual operation of field experts using Jar-test data. In this paper, a systematic control strategy is proposed to derive the optimum dosage of coagulant, PAC(Polymerized Aluminium Chloride), using Jar-test results. A neural network model is developed for coagulant dosing and purifying process by means of six input variables (turbidity, temperature, pH, alkalinity of raw water, PAC feed rate, turbidity in flocculation) and one output variable, while considering the relationships to the reaction of coagulation and flocculation. The model is utilized to derive the optimum coagulant dosage (in the sense of minimizing turbidity of water in flocculator). The ability of the proposed control scheme validated through the field test has proved to be of considerable practical value.