유기농재배 곤달비 지상부 및 뿌리썩음병 보고

박덕환 ( D. H. Park ),변주환 ( J. H. Byeon ),원헌섭 ( H. S. Won ),유재홍 ( J. H. Yoo ),조세열 ( S. Y. Cho ) 강원대학교 농업생명과학연구원(구 농업과학연구소) 2012 강원 농업생명환경연구 Vol.24 No.1

In 2010 to 2011, "Gondalbi" (Ligularia stenocephala) leaves and roots with abnormal characteristics, such as leaf spot and blight, necrosis, powdery mildew, chlorosis, and root rot symptoms were collected in field of Yanggu, Gangwon Province. Similar symptoms have been reported by local farmers since 2008, and they required the identity of those associated pathogens to build up environment-friendly control strategies. Symptoms were primarily divided to black spotted leaf blight, anthracnose, brown leaf spot, leaf blight, powdery mildew, vein necrosis, chlorosis, and root rot based on their typical characteristics, which are the most frequent lesions produced in leaves and roots. In the field, the productions of black spotted leaf blight, anthracnose, brown leaf spot, and leaf blight diseases were highest with daily mean diurnal temperature regimes from 10 to 20℃ and >60% relative humidity; root rot and chlorosis severities was highest in the range of 5 to 10℃, whereas >20℃ of diurnal temperature at the late of harvesting season appeared to be related to vein necrosis and powdery mildew. Twelve fungal stains were isolated from disease samples using potato dextrose agar (PDA) supplemented with kanamycin. Phylogenetic analysis on the basis of partial sequences of the 18S rDNA and ITS region of twelve isolates and reference fungi available in the GenBank, the isolates from black spotted leaf blight, anthracnose, brown leaf spot, and root rot diseases were similarly clustered into Phoma glomerata, Colletotrichum spp., Alternaria brassicae, and Rhizoctonia spp., respectively. To our knowledge, this is the first documented report of the presence of several fungal pathogens and these occurrences increase a significant economic impact to "Gondalbi" at Yanggu country.

계약보증보험 요율산출의 합리적 방안에 관한 연구

박덕환 ( Deokwhon Park ),정세창 ( Sechang Jung ) 한국리스크관리학회 2017 리스크 管理硏究 Vol.28 No.3

본 연구의 목적은 보증보험의 손해율을 결정하는 위험과 보험요율간의 정합성을 제고 할 수 있는 요율산출방식에 대한 연구를 통해 보증보험요율의 적정성을 확보하고 보험가격리스크를 최소화하는데 있다. 이를 위해 보증보험의 손해를 결정하는 가장 중요한 요인이며 보험계약자의 채무불이행정도를 판단하는 대표적 지표인 예상부도율이 국내 은행과 해외 선진보증보험사에서 이자율 및 요율에 각각 어떻게 이용되는 지를 확인하고, 그 방법론을 국내 보증보험 요율개선의 방향성 확보에 활용한다. 아울러 실증적인 요율개선방법을 제시하기 위해 이행(계약)보증보험을 대상으로 내부 신용등급산출모형에 의해 산출된 보험계약자 신용등급과 손해율간의 선형회귀분석을 통해 선형적 상관성을 확인하고 손해율 추정모형을 도출한다. 손해율 추정모형을 활용하여 신용등급에 따른 손해율 상대도를 추정·산출하고 신용등급별로 요율을 차등화 하는 방법을 제시한다. 결과적으로 위험의 크기인 예상부도율에 따라 요율이 합리적으로 차등화 되어 요율의 적정성을 확보할 수 있다. 뿐만 아니라 경영환경의 변화에 따라 보험계약자의 신용등급도 바뀌기 때문에 경기변동 등에 따른 보험계약자의 보험 사고빈도 변화에 의한 손해율의 변동성도 최소화 할 수 있어 요율의 안정성도 제고될 것으로 기대된다. The purpose of this study is to secure an adequate premium rate and to minimize the insurance price risk. This study is based on the research into the ratemaking methodology which would enhance the integrity between: (1) the premium rates; and (2) the risk determining the loss ratio of surety bonds. Part of the matters examined during this study is how domestic banks and surety bonds operating in the advanced countries use the PD, which is a key index determining the principal’s extent of default and is also the most important determinant for the loss in surety bonds, in order to derive their interest rates and premium rates. Their methodologies used to find ways to improve the premium rates are applicable to domestic surety bonds. In addition, in order to present a practical method for premium rate improvement, a linear regression analysis is conducted on the principal’s credit grade and loss ratio which has been calculated by an internal credit grade calculation model for performance bonds. Through the analysis, the linear correlations between the principals’s credit grade and loss ratio are confirmed, and a loss ratio estimation model is generated. With the use of the loss ratio estimation model, the relativity of loss ratios against credit grades is estimated and calculated, and also a method for differentiating the premium rates according to credit grades is presented. Adequate premium rates, thus, can be secured with the premium rates being differentiated according to the PD(size of risk). Also, the volatility of loss ratio, which fluctuates in accordance with the principal’s credit grade subject to change depending on business conditions and is affected by the principal’s loss event frequency, can be minimized. Through this, the stability of premium rate is expected to be improved.

중소기업의 정보화 업무환경이 기업성과에 미치는 영향

박덕환(Durk-Whan Park),곽기영(Kee-Young Kwahk) 한국경영학회 2020 經營學硏究 Vol.49 No.1

This study examines the impact of information systems based working environment of SMEs on firm performance from the perspectives of Resourced-Based View and Endogenous Growth Theories. In addition, the difference between the manufacturing industry group and the non - manufacturing industry group was discussed in terms of the process of leading to the firm performance under the information systems based working environment. In this study, the research model was analyzed using the data of ‘Small and Medium Enterprise IT Information Quality Survey’ conducted from December 11, 2017 to January 19, 2018 at the Ministry of SMEs and startups and TIPA(Korea Technology & Information Promotion Agency for SMEs). The sample used in this study is 3,700 SMEs with ‘fewer than 300 regular employees’, of which 2,073 are manufacturing and 1,627 are non-manufacturing companies. This study suggests the utilization of information system(sales and purchasing system) and business process efficiency as the leading variables influencing the BSC firm performance. According to the results of analysis, four variables of IT environment (Informatization Implementation System, Information System Maintenance, Business Process Rebuild, Information Technology Human Resource) have statistically significant impacts on the utilization of information system, and utilization of information system has a statistically significant effect on business process efficiency and BSC firm performance. Business process efficiency has a statistically significant effect on BSC firm performance. Utilization of information system and business process efficiency have played mediating roles in the research model. In addition, we analyzed the moderating effects of the types of companies that divided the manufacturing and non - manufacturing sectors and suggested the discussions about information systems based working environment of SMEs more specifically.

강원도 사과 재배지역 농약사용실태 분석

박덕환 ( Park,D. H. ),이재홍 ( J. H. Lee ),정태성 ( T. S. Jeong ),황세정 ( S. J. Hwang ),홍대기 ( D. K. Hong ),원헌섭 ( H. S. Won ) 강원대학교 농업생명과학연구원(구 농업과학연구소) 2019 강원 농업생명환경연구 Vol.31 No.1

본 연구는 기후 온난화 등의 원인으로 사과재배 적지로 평가받고 있는 강원도 사과재배 농가의 병해충 방제용 농약사용 경향을 파악하고자 실시되었다. 강원도 7개시 · 군 132 사과재배 농가 농약사용실태 분석 결과, 살균제 및 살충제 각각 8회 살포 농가가 대부분으로, 조사시점인 2017년을 기점으로 각각 10년 및 20년 이전에 비해 살포횟수가 대폭 감소한 것으로 조사되었다. 가장 많이 사용된 살균제는 Dithianon, Tebuconazole 및 Mancozeb 등의 수화제였고, 살충제는 Spirotetramat, Acetamiprid 및 Chlorantraniliprole 등이 사용되는 것으로 조사되어, 미등록 및 비적용 약제의 사용은 이루어지지 않고 있었다. 따라서 적정 농약의 사용을 위하여, 앞으로도 지속적인 병해충 방제용 농약사용실태 조사가 필요하며 이를 통한 강원도 사과재배 맞춤형 농약 및 방제력의 선정이 필요하다. This study was conducted to analyze trends in the usage of fungicides and insecticides in 132 apple orchards in Gangwon Province, where the apple cultivation area has recently increase. The number of treatments with both fungicides and insecticides was eight per orchard, indicating that the number of treatments has reduced compared with that 10-20 years ago. The most frequently used fungicides and insecticides were dithianon, tebuconazole, and mancozeb, and spirotetramat, acetamiprid, and chlorantraniliprole WP, respectively. In addition, the cultivators in Gangwon Province are not treated with unregistered pesticides; thus, we assumed that the apple orchards in Gangwon Province might be appropriate in terms of usage of pesticides based on the guide from RDA (Rural Development Administration). We hope to further develop the adapted control strategies using pesticides in apple orchards in Gangwon Province via continuous monitoring.

Selection of bactericides for suppression of fire blight disease and possible strategies to control it via analyses of transmission routes in Korea

Duck Hwan Park(박덕환) 한국농약과학회 2019 한국농약과학회 학술발표대회 논문집 Vol.2019 No.10

저장기간 및 정식시기가 곤달비 조직배양묘의 생육에 미치는 영향

박종남(Jong Nam Park),최해진(Hae Jin Choi),강영기(Yung Ki Kang),박덕환(Duck Hwan Park),조세열(Sae Youll Cho) 한국원예학회 2011 한국원예학회 학술발표요지 Vol.2011 No.10

MARKOV CHANIN을 이용한 디지틀 전송 에러평가에 관한 연구

박덕환(D. H. Bahk),최봉근(B. C. Choi),박한춘(H. C. Park) 한국통신학회 1990 한국통신학회 학술대회논문집 Vol.1990 No.8

Draft genome sequence of Streptomyces sp. P3 isolated from potato scab diseased tubers

강민규,박덕환,Kang, Min Kyu,Park, Duck Hwan The Microbiological Society of Korea 2018 미생물학회지 Vol.54 No.2

Streptomyces sp. P3 균주는 대한민국 강원도 평창의 더뎅이병 이병괴경으로부터 2017년 분리되었다. 이 논문에서는 9,851,971 bp (71.2% G + C 함량)로 구성된 P3 균주의 전체염기서열을 보고한다. 지놈은 8,548개의 코딩서열, 18개의 rRNA 그리고 66개의 tRNA 유전자를 포함하고 있다. 특히 P3 균주는 감자표면과 무종자를 이용한 병원성 검정에서 병원성을 나타내지는 않았지만, 감자 더뎅이병 유발 Streptomyces들이 보유한 병원성 유전자 중 tomA 유전자만이 존재하였다. 따라서 본 논문에 제공되는 전체염기서열은 감자 더뎅이병원세균들의 병원성 획득을 위한 진화단계에서의 이해를 높이기 위한 중요한 단서가 될 것이다. Streptomyces sp. P3 was isolated from potato scab diseased tubers in Pyeongchang, Gangwon-do, Republic of Korea in 2017. Here, we report the draft genome sequences of P3 with 9,851,971 bp size (71.2% GC content) of the chromosome. The genome comprises 8,548 CDS, 18 rRNA and 66 tRNA genes. Although strain P3 did not show pathogenicity both potato tuber assay and radish seedling assay, it possesses tomatinase (tomA) gene among conserved pathogenicity-related genes in well characterized pathogenic Streptomyces. Thus, the genome sequences determined in this study will be useful to understand for pathogenic evolution in Streptomyces species, which already adapted to potato scab pathogens.

화산력-시멘트 혼합 바이오 블록의 미생물 생장 특성

박성용,박덕환,김현선,김정면,임현택,배수빈,김용성,Park, Sung-Yong,Park, Duck-Hwan,Kim, Hyun-Sun,Kim, Jung-Myeon,Lim, Hyun-Taek,Bae, Su-Bin,Kim, Yong-Seong 한국농공학회 2015 한국농공학회논문집 Vol.57 No.1

This research aims to utilize lapilli from the Mt. Baekdusan as environmently-friendly construction material. First of all, the neutralizing method for fabricating lapilli-cement-mixed bioblock was examined. And then, by use of the neuralized bioblock with microorganism for water purification, the growth inhibition effect against the pathogenic coliform bacillus was evaluated. The result regarding growth inhibition effect on pathogenic coliform bacillus indicates that the pretreatment condition, which is a concurrent procession with aqueous solution of 10% di-ammonium Phosphate after water curing, led to pH degraded below 10 which was the target value. Therefore it was concluded that the method was effective on bio-block neutralization. The microorganisms purifying water and di-ammonium phosphate were detected through the examination for microorganism existence on the bioblock, therefore it was concluded that the bioblock composed of lapilli and cement is able to be utilized in various structures as an environment friendly construction material.

2006~2010년도 국내 노지재배 고추의 바이러스병 발생현황

이장하,홍진성,주호종,박덕환,Lee, Jang Ha,Hong, Jin Sung,Ju, Ho-Jong,Park, Duck Hwan 한국유기농업학회 2015 韓國有機農業學會誌 Vol.23 No.1

2006년부터 2010년까지 국내 고추 노지재배 포장을 대상으로 경상남도와 제주도를 제외한 강원도 11개 지역 등 전국에 걸쳐 총 83개 지역을 중심으로 바이러스 이병체를 채집하여 연차별 고추 발생 바이러스의 발병률, 바이러스 종류 및 감염 형태를 조사하였다. 2006년부터 2010년까지의 고추에서의 평균 단독 감염률은 46.6%, 복합 감염률은 48.0%로 조사되어 고추 생산에 있어서 가장 큰 위해요소는 바이러스 발병으로 나타났다. 바이러스별로는 CMV가 평균 34.8% 발병률로 가장 우점 바이러스로 조사되었다. 반면 BBWV2는 낮은 발병율을 보여주었으며, TSWV는 충남과 전남지역에 국한되는 것으로 조사되었다. 따라서 고추 노지재배 시 발생하는 바이러스의 위해도를 발병률에 따라 구분하면 CMV, PMMoV, 그리고 PepMov 순으로 조사되었다. 또한 복합 감염의 발생도 모든 조사지역 시료에서 검출되었으며, 이에 대한 감염 별 바이러스 종류와 발생률을 분석하였다. 복합 감염에서 가장 빈번하게 검출된 바이러스는 CMV로, CMV+BBWV2, CMV+PepMoV, CMV+PMMoV의 복합 감염형태가 검출률이 높게 나타났다. 따라서 고추의 유기농 재배 생산에 가장 큰 위협요인으로 작용하는 바이러스의 적절한 대책마련을 위한 지속적인 바이러스 모니터링과 3종 이상의 복합 감염 위해성을 판단하기 위한 추가 연구가 필요하다고 사료된다. In this study, viral disease samples were obtained between 2006 and 2010 from pepper fields in 11 major pepper-growing districts in Gangwon-do, and in 83 areas from other provinces, with the exception of Gyeongsangnam-do and Jeju island in Korea. In order to assess the type of infection, field surveys were conducted with regard to viral disease severity and virus type, based on typical symptoms on leaves. The means of single and mixed-virus infections were 46.6% and 48.0%, respectively, during those periods, suggesting that viruses are the agents that most severely decrease pepper production in field cultivation in Korea. In terms of single infection, Cucumber mosaic virus (CMV) was the most prevalent virus based on its disease severity ratings (34.8%). Next, Pepper mild mottle virus (PMMoV) and Pepper mottle virus (PepMoV) were shown to cause severe viral diseases in pepper, with disease severities of around 5-10%. On the other hand, Tomato spotted wilt virus (TSWV) occurs in a limited area in Chungcheongnam-do and Jeollanam-do. Thus, the viral disease caused by CMV, PMMoV, and PepMoV in pepper can be severe, and these virus types should remain considered critical reasons for decreased pepper production in field cultivation in Korea. In addition to single infection, mixed infections are frequently observed in collected pepper samples from all areas. The ratios of mixed infection were therefore studied to evaluate the disease severity of mixed infections and to define individual virus types. These data showed that different types of viruses were present, and CMV was the most abundant virus for mixed infection, as in the case of single infection. Among mixed infections, the highest disease severity was seen with CMV+Broad beam wilt virus 2 (BBWV2), followed by other types of mixed infection such as CMV+PepMoV and CMV+PMMoV. However, further work is needed to reduce the severe damage caused by viruses and to assess mixed infection types involving three or more viruses.