• 한국표면공학회지
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• 제46권3호
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• pp.126-132
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• 2013

It was investigated that the effects of hydrogen charging on the properties of 590 MPa Dual Phase(DP) steels at the surface layers. The hydrogen-charging time was changed from 5 to 50 hours and current densities from 100, 150, and 200 $mA/cm^2$, respectively. It was found that the hydrogen content in the specimen was increased with as the charging time and the current density. The microvickers hardness of the subsurface zone was increased from 215.3 HV to 239.5 HV due to the increase in current density and charging time. The comparison of the absorbed energies tested by a small-punch (SP) test showed that the absorbed energy of the specimen was greatly reduced from 436 to 283 $kgf-mm^2$ because of hydrogen embrittlement. It was confirmed that bulb aspects of fracture surface became more brittle with increasing hydrogen content.

• The Plant Pathology Journal
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• 제23권4호
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• pp.295-299
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• 2007

These experiments were carried out to examine efficacy of soil solarization for control of pink root disease by means of mulching with transparent polyethylene sheets in the hot season. The effects of soil solarization on incidence of pink-root disease caused by Pyrenochaeta terrestris and on onion growth and on populations of soil fungi were investigated. Solarization was dramatically effective in reducing pink root incidence in onion seedling and harvested onion bulb. A 30-day and 40-day solarization treatment significantly improved seedling survival and increased yield of 'Changnyeong-deago' onion while decreasing incidence of pink root. Populations of soil fungi from fields planted to onion were assayed on selective media. Solarization treatment was effective in reducing populations of P. terrestris, Pythium spp., and Rhizoctonia sp. in soil. Increase of yield of onion bulbs was associated with control of soil-borne pathogenic fungi. Soil solarization had beneficial effects on yield, bulb diameter, or incidence of pink root.

• Parasites, Hosts and Diseases
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• 제58권6호
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• pp.695-699
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• 2020

Present study was performed to know the infection status of Gnathostoma sp. larvae in swamp eels from Cambodia. We purchased total 30 Asian swamp eels, Monopterus albus, from local markets in Pursat and Takeo Provinces and Phnom Penh on May and November 2017 and May 2018. All collected eels were transferred to our laboratory with ice and each of them was examined by artificial digestion method. A total of 15 larval gnathostomes (1-5 larvae) were detected from 55.6% (5/9) swamp eels in Pursat Province. No larval gnathostomes were found in 21 swamp eels in Takeo Province and Phnom Penh. The advanced third-stage larvae (AdL3) detected were 2.575-3.825 (3.250) mm in length and 0.375-0.425 (0.386) mm in width. They had the characteristic head bulb (av. 0.104×0.218 mm) with 4 rows of hooklets, long muscular esophagus (1.048 mm), and 2 pairs of cervical sacs (0.615 mm). The number of hooklets in 4 rows on the head bulb was 41, 44, 47, and 50. In scanning electron microscopy, characteristic features were 4 rows of hooklets on the head bulb, cervical papillae, tegumental spines regularly arranged in transverse striations, and anus. The larval gnathostomes were identified as AdL3 of Gnathostoma spinigerum based on the morphological characters. By the present study, it has been confirmed that G. spinigerum larvae are infected in Asian swamp eels, M. albus, in Pursat Province, Cambodia.

• 한국철도학회논문집
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• 제16권6호
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• pp.473-481
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• 2013

본 연구에서는 미생물 반응으로 생성된 탄산칼슘을 현장조건과 유사한 장비로 제작하여 모래지반에 주입함으로 모래지반의 강도 개선 및 주입범위를 평가하고자 하였다. 본 연구를 분석하기 위해 단층토(Sand, SP, SW)는 D 150mm ${\times}$ H 200mm로 3가지 case를 제작하였고, 다층토(SW/SP, SP/SW)는 D 150mm ${\times}$ H 300mm로 제작하여 2가지 case를 Dr 30%인 연약지반으로 제작하여 1일 동안 주입실험을 수행하였다. 포켓관입시험기로 일축압축강도를 측정하였고, 주입노즐 주변의 구근형성을 통해 주입범위를 살펴보았다. 또한, XRD분석 통해 공시체내의 성분분석을 진행하였다. 그 결과, 다층토에서 SP/SW에서 전구간에 걸쳐 약 500kPa의 강도와 15cm 두께의 고결을 확인하였다. 이는 바이오그라우팅 기술이 지반의 간극 상태와 크기에 따라 주입 효과에 상당한 영향이 있음을 확인 할 수 있었다.

• 식물병연구
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• 제9권2호
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• pp.79-84
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• 2003

2001년 8월에서 2002년 7월까지 경기도내 주요 시설하우스 재배지에서 시클라멘 시들음병 발생을 조사한 결과 전지역에서 발생이 확인되었으며, 김포에서는 발병주율이 42.7%까지 되었다. 시들음병 발생은 관행적인 지상관수방법보다 저면관수에서 발생이 더 심하였다. 발병된 시클라멘 잎은 황화되고 병이 진전되면 고사하였으며 구근에서는 갈변 증상이 관찰되었다. 갈변된 구근 조직에서 병원균을 분리하여 fusarium oxysporum f. sp. cyclaminis로 동정하였다. 발병지 상토를 수거하여 시클라멘을 이식했을 때 100% 발병하였다. 저항성 품종 선발에서는 'Matis red', 'Schubert', 'Victoria', 'Chopin'의 4품종만이 저항성 품종으로 검정 되었을 뿐 대부분의 품종이 감수성이었다. 시들음병 방제약제 선발 결과 방제 효과는 비교적 낮았으나 병원균 접종 전 약제처리시 베노밀 수화제와 후루 디옥소닐 액상수화제의예방 효과가 인정되었다. 그리고 병을 Fusarium oxysporum f. sp. cyclaminis에 의한 시클라멘 시들음병으로 명명할 것을 제안한다.

• Parasites, Hosts and Diseases
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• 제23권1호
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• pp.1-6
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• 1985

Five cases infected with Rhabditis sp. were detected in a survey to examine the stool specimens from rural primary school children. A large number of the larvae of Rhabditis sp. detected by the direct cellophane thick smear were cultured by the alter paper method. The eBamination was carried out in April through June, 1980 in Tangjeong-Myon, Ahsan.Gun, and in September 1983 in Sandong-Eup, Yeongwol-Gun. The results obtained in this study were as follows: 1. Prevalence: Out of 925 children, 5(0.54%) children were found to be positive. The number of the detected larvae was 110/0.1gm of feces in case 1, 35 in case 2, 130 in case 3, 86 in case 4 and 62 in case 5. 2. Larvae: The larvae were prepared by means of the direct fecal smear and measured by a micrometer equipped in the microscope. Twelve (12) through 15-day old larvae in culture were $197.1{\mu}{\textrm{m}}$ long in average, and the maximum size of the matured stage larvae was $884.0{\times}25.9{\mu}{\textrm{m}}$. However, the length variation was ranged as 173.0 to $884.0{\mu}{\textrm{m}}$. 3. Adults: The size of clubbed adult female was $1, 357{\mu}{\textrm{m}}(1, 176~1, 419)$ in length and $80{\mu}{\textrm{m}}(79~82)$ in width. Length of buccal cavity was $33{\mu}{\textrm{m}}$. A long cylindrical esophagus($273{\mu}{\textrm{m}}$) of the worms with a valved posterior cardiac bulb and with median bulbar swelling was morphologically indicated. Ditance from mouth to vulva was occupied 58% of body length. Male worm was $1, 006{\mu}{\textrm{m}}(890~1, 148)$ in length and $49{\mu}{\textrm{m}}(48~49)$ wide. Caudal alee of bursa and spicules ($75{\mu}{\textrm{m}}$ in length) were well developed. 4. Eggs: The oval shaped eggs in the female uterus, when cultured, were $66{\times}56{\mu}{\textrm{m}}$ in sixte, and the eggs laid by the adult could not be detected. So, reproduction might be thought to be ovoviviparity. 5. The five cases were re-examined during the period from the 1st to the 3rd week after stool examinations, but Rhabditis sp. were detected again in 4 cases in 1st week. When they were examined in 3rd week, larvae could not be detected. So, it was thought that the infection of Rhabditis sp. to humans was facultative.

• 한국토양비료학회지
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• 제21권2호
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• pp.183-193
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• 1988

본(本) 연구(硏究)는 유황시비(硫黃施肥)에 따른 마늘의 품질(品質)과 수량(收量)에 미치는 영향(影響)에 관한 시험(試驗)으로서 1986년산(年産) 서산한지형(寒地形) 마늘을 pot 및 포장(圃場)에서 유황시용량(硫黃施用量) 5개처리구(個處理區)(0, 10, 20, 30, 40kg/10a)를 3반복(反覆) 난괴법(亂塊法)으로 배치(配置)하여 재배(栽培)하였다. 재배기간중(栽培期間中) 주요(主要) 생육단계별(生育段階別)로 7회에 걸쳐 지상부(地上部)와 지하부(地下部)의 생육특성(生育特性) 및 수량조사(收量調査)와 마늘향기(香氣)의 주성분(主成分)인 diallyl disulfide를 비롯한 14종의 유기유황(有機硫黃) 화합물(化合物)을 GC 및 GC/MASS로 분리(分離), 확인(確認), 정량(定量)하여 얻은 결과(結果)를 요약(要約)하면 다음과 같다. 1. 지상부(地上部)의 생육조사(生育調査) 결과(結果)는 유황시비량(硫黃施肥量)에 따라 영향(影響)을 미치지 않으나, 지하부(地下部) 수량(收量)에 영향(影響)을 미치는 것으로 나타났다. 2. Pot 시험(試驗)에서는 10a당(當) 유황(硫黃) 10kg 시비해당구(施肥該當區)인 처리구(處理區)(S-10)에서, 포장시험(圃場試驗)에서는 20kg 시비(施肥)한 처리구(處理區)(SF-20)에서 마늘구근(球根)의 수량(收量)이 가장 많았다. 3. 마늘 향기성분(香氣成分)의 주성분(主成分)으로서 휘발성(揮發性) 유기유황(有機硫黃) 화합물(化合物)인 diallyl sulfide, allyl methyl dithia cyclo pentene, methyl propyl disulfide(Z+E), diallyl disulfide, dipropenyl disulfide, dipropenyl disulfide(isomer), allyl methyl trisulfide, 3-vinyl-1, 2-dithia cyclo bexa-5-ene, 3-vinyl-1, 2-dithia cyclo hexa-4-ene, diallyl trisulfide, allyl propyl trisulfide 및 dipropenyl trisulfide의 함량(含量)은 pot 시험(試驗)에서는 SP-10, 포장시험(圃場試驗)에서는 SF-20구(區)에서 가장 높았다. 4. 상기(上記) 유기유황화합물(有機硫黃化合物)은 생육초기(生育初期)부터 지상부(地上部)에서 생합성후(生合成後) 지하부(地下部)로 이동(移動)되는 것으로 판단(判斷)되었다. 5. 마늘의 수량(收量), 마늘중 총유황(總硫黃) 및 휘발성(揮發性) 유기유황(有機硫黃) 향기성분함량(香氣成分含量)의 측면(側面)에서 판단(判斷)할 때 본(本) 시험(試驗)에 사용된 공시품종(供試品種)과 토양조건(土壤條件)에서는 10a당(當) 20kg의 유황시비구(硫黃施肥區)에서 포장경작시(圃場耕作時) 수량(收量)과 품질(品質)이 가장 양호(良好)한 것으로 나타났다.

• The Plant Pathology Journal
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• 제17권3호
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• pp.141-148
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• 2001

Postharvest decay of onion bulbs was examined by inspecting the commercial packages in the market or in storage. Bulb rot incidence was unexpectedly high, and onion bulbs with 1st quality grade were rotten most severely by 51%, followed by 32% for 2nd and 21% for 3rd grades. This indicates that larger bulbs had higher incidences of bulb rots. Major pathogens associated with basal and neck rots were Fusarium oxysporum and Aspergillus sp. or Botrytis allii, respectively, of which basal rot was most prevalent and damaging during storage. Among the epiphytic microorgani는 from onion plants, several Bacillus and Paenibacillus spp. and previously selected Pseudomonas putida and Trichoderma harzianum had inhibitory efficacy against bulb rot pathogens. Among these B. amyloliquefaciens BL-3, Paenibacillus polymyxa BL-4, and P. putida Cha 94 were highly inhibitory to conidial germination of F. oxysporum and B. allii. P. putida Cha 94, B. amyloliquefaciens BL-3, P. polymyxa BL-4, and T. harzianum TM were applied in the rhizoplane of onion at transplanting. Initially antagonist populations decreased rapidly during the first one month. However, among these antagonists, rhizoplane population densities of BL-3, Cha 94, and TM were consistently high thereafter, maintaining about 10$^4$-10$^{5}$ cells or spores per gram of onion root up to harvest time. The other bacterial antagonist BL-4 survived only for two months. TM was the most effective biocontrol agent against basal rot, with the number of rotten bulbs recorded at 4%, while that of the control was 16%. Cha 94 was effective for the first 20 days, but basal rot increased thereafter and had about the same control efficacy as that of BL-3 and BL-4. When the antagonists were applied to the topping areas of onion bulbs at harvest, TM was the most effective in protecting the stored onion bulbs from neck rotting. The second effective antagonist was BL-3. TM and BL-3 completely suppressed the neck rot in another test, suggesting that biocontrol of postharvest decay of onion using these microorganisms either at the time of transplanting or at harvesting may be promising.

• 한국산학기술학회논문지
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• 제16권6호
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• pp.4276-4283
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• 2015

본 연구에서는 미생물 반응으로 생성된 탄산칼슘을 현장에서 활용되고 있는 주입장비와 유사하게 제작하여 모래지반에 주입함으로 지반조건에 따른 주입범위 및 주입효과를 확인하고자 하였다. 본 연구를 위해 2종류의 단층토(SP, SW)를 D 150mm ${\times}$ H 300mm의 모형토조에 상대다짐도 80, 85, 90, 95%로 제작하여 주입실험을 수행하였다. 주입 후 강도개선효과를 확인하기 위해 일축압축강도를 측정하였고, 주입노즐 주변의 구근형성을 통해 주입범위를 살펴보았다. 그 결과, SW시료는 상대다짐도 85% 이상에서 주입률이 10% 이하로 나타났으며, 지반의 상대다짐도에 따라 Bio-grouting의 주입률 및 고결범위에 영향이 있음을 확인 할 수 있었다.

• Parasites, Hosts and Diseases
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• 제53권5호
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• pp.619-625
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• 2015

The present study was performed to determine the infection status of swamp eels with Gnathostoma sp. larvae in Myanmar. We purchased total 37 Asian swamp eels, Monopterus albus, from a local market in Yangon in June and December 2013 and 2014. All collected eels were transferred with ice to our laboratory and each of them was examined by the artificial digestion technique. A total of 401 larval gnathostomes (1-96 larvae/eel) were detected in 33 (89.2%) swamp eels. Most of the larvae (n=383; 95.5%) were found in the muscle. The remaining 18 larvae were detected in the viscera. The advanced third-stage larvae ($AdL_3$) were 2.3-4.4 mm long and 0.25-0.425 mm wide. The characteristic head bulb ($0.093{\times}0.221mm$ in average size) with 4 rows of hooklets, muscular long esophagus (1.025 mm), and 2 pairs of cervical sacs (0.574 mm) were observed by light microscopy. The average number of hooklets in the 1st, 2nd, 3rd, and 4th rows was 41, 45, 48, and 51, respectively. As scanning electron microscopic findings, the characteristic 4-5 rows of hooklets on the head bulb, a cervical papilla, tegumental spines regularly arranged in the transverse striations, and an anus were well observed. Based on these morphological characters, they were identified as the AdL3 of Gnathostoma spinigerum. By the present study, it has been confirmed for the first time that Asian swamp eels, M. albus, from Yangon, Myanmar are heavily infected with G. spinigerum larvae.