• 소성∙가공
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• 제8권1호
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• pp.78-91
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• 1999

The endless hot rolling has been focused as an innovative process technology for increasing the productivity drastically and reducing the imperfection of quality in hot rolled steel strip. To realize it in actual mill, a lots of new facilities such as bar coiler, movable LASER welder and high speed strip shear should be equipped. And also it is necessary to develop the control technique for changing the roll gap and rolling speed during rolling, which is named as Flying Gap and Speed Change control technology. To prevent a strip rupture caused by excessive tension, it is very important to minimize fluctuations in strip thickness and intension during FGSC control. In this paper, the mathematical model for FGSC control algorithm was suggested and dynamic simulation is performed to accertain the effect of suggested control method on fluctuations in strip thickness and tension. For endless hot rolling simulation, a lots of FGSC control situations, for instance - strip thickness change from strip to strip - strip width change from strip to strip - carbon content change from strip to strip are considered.

• 미생물학회지
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• 제18권3호
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• pp.133-147
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• 1980

Washed mycelia of Aspergillus nidulans FGSC159 were incubated in CMC minimal liquid medium and the culture filtrate which contained induced extracellular cellulase was fractionated by a three-step procedure including chromatography on Bio-Gel P-150, chromatography on DEAE-Sephadex A-50 and chromatography on Sephadex G-100. Three CMCase components ; F-I-Ia, F-I-Ib and F-II-Ia were prepared. No enzyme activity toward avicel could be detected in these components. Similarly, there was no ${\beta}-glucosidase$ activity. pH-optima of the three components were all 5.0 in acetate buffer. Temperature-optima for the activities of F-I-Ia, F-Ib and F-II-Ia were $45^{\circ}C,\;40^{\circ}C\;and\;50^{\circ}C$, respectively. F-II-Ia was shown to be more thermostable than the other two components. F-II-Ia was proved to have quite a different substrate specificity and action property and action property from those of F-I-Ia and F-I-Ib by product analysis on liquid chromatography.

• 식물병연구
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• 제24권4호
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• pp.313-320
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• 2018

벼 붉은곰팡이병에 대한 품종별 반응과 기상조건에 따른 감염영향을 알아보기 위하여 장려품종 재배포장의 기상자료와 수확한 벼의 이병립율과 Fusarium 균을 동정하였다. 출수개화 전인 7월 하순부터 등숙기인 9월말까지의 평균기온이 수확후 산물벼의 이병립율에 크게 영향을 주었으며, 평균기온이 비슷한 2010년과 2013년에는 같은 기간의 누적강우량, 누적 강우일수, 2일 이상 강우지속횟수와 관련이 있었다. 2010년과 2013년에 수확한 벼에서 Fusarium 균의 종복합체별 분리비율은 FGSC에 대해 각각 57%과 45%, FIESC에 대해 35%과 50%, FFSC에 대해 8%과 5%이었다. FGSC와 FFSC의 분포비율은 2010년이 2013년에 비해 높았다. Fusarium 균의 자연감염에 대한 품종반응은 26개 장려품종 중 미향 품종만이 FGSC 자연감염에 대한 저항성을 보였으며, 남평, 하이아미, 영호진미 품종은 총 Fusarium 병원균의 자연감염에 대하여 전반적인 저항성을 보였다. 그 밖의 대부분의 장려품종은 저항성 또는 감수성으로 구분할 수 없었다. 본 연구결과는 Fusarium 균 자연감염에 대한 저항성과 감수성을 판단하는 기초자료로서 의의가 있다.

• 한국균학회지
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• 제17권3호
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• pp.154-160
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• 1989

핵전이 기술을 이용하여 Aspergillus nidulans에서의 종내잡종들을 얻어내고 이들의 섬유질 분해효소계 활성 및 핵형분석을 통하여 이 방법에 의한 균주개량의 가능성을 조사하였다. A. nidulans 야생균주와 영양요구성 돌연변이주 FGSC 475로부터 추출한 핵을 FGSC 514의 원형질체에 각각 전이시킨 결과 4.8% 및 10.1%의 잡종형성율을 나타냄으로써, 0.6%의 융합빈도를 보인 원형질체 융합법보다 핵전이법이 잡종형성에 더 효과적임을 알 수 있었다. 또한 형성된 잡종들에서 cellulase및 xylanase system과 mannanase 중 일부분의 효소성분의 활성이 향상된 균주가 분리되어 이 방법에 의한 우수 섬유질분해 균주개발의 가능성을 확인할 수 있었으며, 형성된 잡종의 핵형은 이배체 또는 이수체로 분석되었다.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2016년도 춘계학술대회 및 임시총회
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• pp.33-33
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• 2016

Mycotoxins are toxic secondary metabolites produced by fungi. They can be present in where agricultural-based commodities are contaminated with toxigenic fungi. These mycotoxins cause various toxicoses in human and livestock when consumed. Small grains including corn, barley, rice or wheat are frequently contaminated with mycotoxins due to infection mainly by toxigenic Fusarium species and/or under environment favorable to fungal growth. One of the most well-known Fusarium toxin groups in cereals is trichothecenes consisting of many toxic compounds. Deoxynivalenol (DON), nivalenol (NIV), T-2 toxin, and various derivatives belong to this group. Zearalenone and fumonisin (FB) are also frequently produced by many species of the same genus. In order to monitor Korean cereals for contamination with Fusarium and other mycotoxigenic fungal species as well, barley, corn, maize, rice grains, and soybean were collected from fields at harvest or during storage for several years. The fungal colonies outgrown from the grain samples were identified based on morphological and molecular characteristics. Trichothecene chemotypes of Fusarium species or presence of FB biosynthetic gene were determined using respective diagnostic PCR to predict possible toxin production. Heavy grain contamination with fungi was detected in barley, rice and wheat. Predominant fungal genus of barley and wheat was Alternaria (up to 90%) while that of rice was Fusarium (~40%). Epicoccum also appeared frequently in barley, rice and wheat. While frequency of Fusarium species in barley and wheat was less than 20%, the genus mainly consisted of Fusarium graminearum species complex (FGSC) which known to be head blight pathogen and mycotoxin producer. Fusarium composition of rice was more diverse as FGSC, Fusarium incarnatum-equiseti species complex (FIESC), and Fusarium fujikuroi species complex (FFSC) appeared all at considerable frequencies. Prevalent fungal species of corn was FFSC (~50%), followed by FGSC (<30%). Most of FFSC isolates of corn tested appeared to be FB producer. In corn, Fusarium graminearum and DON chemotype dominate within FGSC, which was different from other cereals. Soybeans were contaminated with fungi less than other crops and Cercospora, Cladosporium, Alternaria, Fusarium etc. were detected at low frequencies (up to 14%). Other toxigenic species such as Aspergillus and Penicillium were irregularly detected at very low frequencies. Multi-year survey of small grains revealed dominant fungal species of Korea (barley, rice and wheat) is Fusarium asiaticum having NIV chemotype.

• 미생물학회지
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• 제23권1호
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• pp.34-42
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• 1985

Cellulase의 합성 및 그의 조절기작을 밝히기 위한 기초연구로서 Aspergillus nidulans FGSC 168로 부터 CMC 배지에서 자라지 못하는 돌연변이주인 TCD27, NCN2, ACN 14, ACN3를 얻어내어 이들의 성질을 분석하였다. 이들 4가지 돌연변이주는 모두 inducer를 세포내로 수송하는 permease를 만들어 내는 유전자에는 아무 결함이 없었다. 이들 중 ACN3는 cellulase의 합성 및 그의 조절 기작과는 직접 관련이 없는 돌연변이주로 추정되나, TCD 27과 NCN2는 조절 유전자에 돌연변이가 일어났을 가능성이 있고, ACN 14는 구조 유전자 돌연변이주일 것으로 추정되었다.

• 한국균학회지
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• 제50권4호
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• pp.281-289
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• 2022

붉은곰팡이병은 곡류의 중요한 병이며 Fusarium graminearum species complex (FGSC)에 속하는 균들에 의해 발생한다. 맥류 재배 농가들은 이 병을 방제하기 위해 탈메틸화 억제제인 triazole계 살균제를 살포한다. 본 연구는 FGSC 집단에서 triazole계 살균제인 propiconazole에 대한 감수성의 변화를 조사하기 위해 수행되었다. 2010-2016년과 2020-2021년 동안 전남북의 보리와 밀에서 124개와 350개의 FGSC 균주를 각각 분리하였다. 균주들의 종 동정 및 트리코테센 독소화학형은 각각 translation elongation factor 1-alpha 및 TRI12 유전자를 표적으로 하는 PCR 분석을 기반으로 결정되었다. propiconazole에 대한 민감도는 한천 희석법을 사용하여 균사체 성장을 50% 감소시키는 유효 농도(EC₅₀)를 기준으로 결정되었다. 모든 균주에서 nivalenol 독소화학형의 F. asiaticum이 가장 많았으며(2010-2016년 83.9%, 2020-2021년 96.0%), 3-acetyl deoxynivalenol 독소화학형의 F. asiaticum (2010-2016년 12.1%, 2020-2021년 2.9%)이 그 다음이었다. 2010-2016년과 2020-2021년에 수집된 균주의 EC₅₀ 값은 각각 0.0180-11.0166 ㎍/mL 및 1.3104-17.9587 ㎍/mL 범위였으며, 평균 EC₅₀ 값은 2010-2016년 3.8648 ㎍/mL에서 2020-2021년 5.9635 ㎍/mL로 증가했다. 2010-2016년 균주의 EC₅₀ 값을 바탕으로 7.0 ㎍/mL을 저항성 기준으로 정하였고, 저항성 균주의 수는 2010-2016년 9.7%에서 2020-2021년 28.6%로 증가한 것으로 나타났다.

• The Plant Pathology Journal
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• 제32권5호
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• pp.407-413
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• 2016

Fusarium graminearum species complex (FGSC) causes Fusarium head blight in small grain cereals. To date, four species (F. graminearum, F. asiaticum, F. boothii, and F. meridionale ) belonging to FGSC frequently occur in Korean cereals. In addition, we first reported the occurrence of additional species (F. vorosii ) within FGSC, which was isolated from barley, corn, and rice in Korea. Phylogenetic analysis of the Fusarium isolates of this group using combined multigene sequences confirmed species identification. Moreover, the macroconidia produced by these isolates were morphologically similar to those of the F. vorosii holotype. Chemical analysis indicated that the F. vorosii isolates produced various trichothecenes such as nivalenol and deoxynivalenol with their acetyl derivatives along with zearalenone. Pathogenicity tests demonstrated that all of the F. vorosii isolates examined were pathogenic on barley, corn, and rice with variation in aggressiveness. This study is the first report of F. vorosii in Korean cereals, their pathogenicity towards barley and corn, and their ability to produce trichothecenes and zearalenone.

• Ocean Systems Engineering
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• 제3권3호
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• pp.237-255
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• 2013

In many applications, Remotely Operated Vehicles (ROVs) are required to be capable of course keeping, depth keeping, and height keeping. The ROV must be able to resist time-variant external forces and moments or frequent manipulate changes in some specified circumstances, which require the control system meets high precision, fast response, and good robustness. This study introduces a Fuzzy-Incomplete Derivative Ahead-PID (FIDA-PID) control system for a 500-meter ROV with four degrees of freedom (DOFs) to achieve course, depth, and height keeping. In the FIDA-PID control system, a Fuzzy Gain Scheduling Controller (FGSC) is designed on the basis of the incomplete derivative ahead PID control system to make the controller suitable for various situations. The parameters in the fuzzy scheme are optimized via many cycles of trial-and-error in a 10-meter-deep water tank. Significant improvements have been observed through simulation and experimental results within 4-DOFs.

• 미생물학회지
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• 제20권4호
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• pp.173-182
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• 1982

From FGSC 159 strain of Aspergillus nidulans, temperature sensitive mutants that are defective in growth and differentiation have been isolated by N-methyl-N'-nitroN-nitrosoguanidine (NTG) treatment. The optimum concentration of NTG and incubation time to get the highest mutation frequency was $100{\mu}g$ per ml and 1 hour, respectively. The survival frequency was 1%. Among the isolated mutants, five strains that were affected in early steps of differentiation were selected for further studies and named smK, smY, smB, smF, and smZ. The execution point of each mutant was determined and the growing pattern of each mutant at the restrictive temperature was observed under the microscope. Growth of mutant was arrested near at the execution point. From genetic analysis, each temperature-sensitive mutants was thought to have a single recessive gene. The genes of smK, smY, smB, smF, and smZ are linked to the chromosome VII, IV, VIII, I, and VI, respectively. It can be concluded that the genes controlling the differentiation are widely dispersed in the genome. From the results of mutant, smK, it is considered that a single gene can affect a function (functions) which act(s) at two different steps during differentiation.