• Journal of Korean Society of Forest Science
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• v.102 no.2
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• pp.300-304
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• 2013

Pine wilt disease caused by pine wood nematode, Bursaphelenchus xylophilus (Steiner et Buhrer) Nickle, has become the most serious threat to pine trees in Korea since 1988. Pine wood nematode is transferred to healthy trees by Monochamus alternatus (Coleoptera: Cerambycidae) during its maturation feeding and female oviposition. A typical control method against insect vectors in Korea is fumigation of the dead trees by using metam-sodium SL (25%). However, this method is not environment friendly because of the forest contamination by chemical application and destroying landscape by plastic cover. Portable Bark Remover (PBR) was invented to reduce these environmental problems. The vectors oviposit under the bark of the newly dead trees only. Debarking infested trees prevents the vectors from laying eggs and eventually, they can not complete their life cycle. The PBR is a modified debarking device that is attached on the top of the electrical chain saw, which allows ease and rapid debarking of the infested trees. The new method by PBR is expected to be more economic and effective than other conventional methods such as "crushing", "burning" and "fumigation".

• Korean Journal of Ichthyology
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• v.22 no.2
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• pp.83-89
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• 2010

We studied the maturity and spawning of Marbled sole Pleuronectes yokohamae from May 2006 to April 2007 in the Southern Sea of Korea. We analyzed monthly changes in maturity stages, gonadosomatic index (GSI), egg diameters, fecundity (F), total length (TL) at 50% group maturity, and sex ratio. The spawning period was November to February, and the main spawning period was December to January. The fecundity ranged from 75,155 eggs at 17.8 cm(TL) to 1,307,195 eggs at 36 cm (TL), and the relationship between TL and F was $F=3.656TL^{3.518}$ ($R^2$=0.872). The TL at first maturity was 17.8 cm and at 100% maturity, 32 cm. Thus, TL at 50% group maturity was estimated to be 19.8 cm. For sex ratio by length class, males were slightly predominant at sizes under 25 cm TL, but females were 100% at greater than 32 cm TL.

• Korean Journal of Ichthyology
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• v.18 no.4
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• pp.363-367
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• 2006

The maturity and spawning of brown sole, Pleuronectes herzensteini were investigated using samples randomly collected in the East Sea of Korea from April, 2003 to March, 2004. We analyzed monthly changes in maturity stages, gonadosomatic index (GSI), egg diameter, fecundity (F), total length (TL) at 50% group maturity, and sex ratio. The spawning period was February to May, and the main spawning period was March to April. The fecundity was 38,702 eggs at 22 cm (TL) to 133,085 eggs at 37 cm (TL), and the relationship between TL and F was $F=11.307TL^{2.628}$. The TL at first maturity was 15 cm and at 100% maturity, 21 cm. Thus, TL at 50% group maturity was estimated to be 17.8 cm, which corrensponded to the age of 3 years. The sex ratio was 60.2 for female and 39.8 for male, where the female population was seen to be slightly predominant.

• The Korean Journal of Malacology
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• v.25 no.2
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• pp.127-133
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• 2009

The common octopus, Octopus vulgaris is commercially important species in Korea. Korean fishing vessels have actively caught it. However, the study of this species has been poorly known. Therefore, the purpose of this study is to provide information about maturation and spawning period of this species. Samplings have been monthly collected in Tongyoung and Sacheon of Gyeongsangnam-do, using traps. A total of 748 individuals were sampled from February 2007 to January 2008. We analyzed monthly changes in maturity stages, gonadosomatic index, total weight at 50% group maturity. The octopus total weight was between 128.6 and 3381.4 g. Females were distributed between 129.8 and 3381.4 g and males between 128.6 and 2378.4 g. The spawning periods were May to June and September. The total weight at 50% group maturity was estimated to be 919.6 g.

• KOREAN POULTRY JOURNAL
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• v.5 no.10 s.48
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• pp.57-72
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• 1973

1. 육추율, 육성율, 성계생존율 육추율은 99.9$\%$로서 1회 98.5$\%$, 2회 99.2$\%$, 3회 99.8$\%$, 4회 98.3$\%$, 5회 98.7$\%$, 6회 99.7$\%$와 비슷하였다. 육성율은 평균 98.8$\%$로서 1회 97.5$\%$, 2회 97.2$\%$, 3회 96.6$\%$, 4회 97.9$\%$와는 큰차가 없었고 5회 89.7$\%$ 6회 87.1$\%$ 보다는 약 12$\%$가 높게 나타났다. 이는 MD 백신접종 때문인 것으로 생각되며 성계생존율은 평균 86.3$\%$로서 87.3$\%$ 보다는 약 1$\%$낮았고 1회 80.3$\%$ 2회 84.8$\%$보다는 약 4.6$\%$ 높고 3회 71.8$\%$, 5회 71.4$\%$, 6회 75.3$\%$에 비하면 19$\%$나 높았다. 2. 성성숙일령 전체평균은 157.3일로 가장 빠른 구는 4구의 146일이고 가장 늦은 구는 10구와 17구의 161일이였다. 3. 산란율, 산란지수 산란율은 평균 62.0$\%$이고 가장 높은 구는 15구의 68.9$\%$ 이였다. 산란지수는 평균 205.1개로 1회 190.8, 2회 198.3, 3회 184.2, 5회 186.5, 6회 189.7개에 비하여 높고 4회때와 근사하였다. 4. 사료요구율 전체평균 3.23으로 1회 3.54, 2회 3.1과는 근사하나 3회 2.98, 4회 2.87 5회 2.83에 비하여 낮은 것은 사양표준은 작년도와 같으나 원료사료 특히 단백질 사료의 품질저하에 원인이 있었다. 5. 난평균 중량 검정계군 전체의 평균난중은 61.2g으로 최상위구는 64.70g, 최하위구는 58.3g이였다. 6. 체중 검정계의 전체의 평균제중은 300일령 1925.1g, 500일 1938.4g이며 유색품종은 300일령 1986.7g, 500일령 1948.4g이였다. 7. 사료섭취량 사료섭취량 평균은 1일수당 육추기 32.1g 육성기 73.0g 산란기 115.6g이었다. 8. 경제성 총 수입은 7,269,072.34으로 전체수입의 85$\%$가 계란수입이고 15$\%$는 폐계수입이었다. 지출은 5049,690으로 전체 지출의 99.95$\%$가 사료비 0.05$\%$가 초생추대이었다. 9. 후기 검정수수미달은 참고구로 처리하였고 축산시험장과 대천종축장에서는 당초부터 참고구로 출품하였다. 대신의 개리슨, 신기의 하바드 코메트는 수정율이 낮아서 검정수수가 미달되었으며 영국의 Sykes International Co. 에서 출품한 Sykes Tinted(WL$\times$RIR BX)는 출품회사에서 직접 종란을 항공편에 보내 인수 부화하여 검정하였다. 7회 부터는 초생추에 MD(뎁타백) 백신을 하여 초산전후에 폐사율이 적었으며 72년 11월부터 국산어분에 의한 염도의 과다에 의하여 약 2주일 설사를 하여 상당히 스트레스를 받은 바 있었다.

• Korean Journal of Ichthyology
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• v.19 no.3
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• pp.179-184
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• 2007

Maturity and spawning of spinyhead sculpin, Dasycottus setiger were investigated using samples collected by the eastern sea danish seine and gillnet in the East Sea of Korea from January to December 2004. We analyzed monthly changes in maturity stages, gonadosomatic index (GSI), egg diameter, fecundity, total length at 50% group maturity, and sex ratio. GSI began to increase in August, reached a maximum between September and November, and decreased in December. The spawning period was August to December, and the main spawning period was September to November. The fecundity ranged from 6,210 eggs at 22.3 cm (TL) to 15,898 eggs at 32.2 cm (TL). The relationship between total length (TL) and fecundity (F) was $F=25.475TL^{1.818}$ ($R^2=0.761$), and F increased with TL. The TL at 50% group maturity was estimated to be 23.4 cm. The sex ratio was 1 : 1.3 (female : male), indicating the male population was seem to be slightly predominant.

• Journal of Aquaculture
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• v.8 no.3
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• pp.195-207
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• 1995

In order to study the embryonic development and hatching of wild long shanny, Stichaeus grigorjewi, were caught with the gill nets in the East Sea of Korea, and stocked at indoor tanks to induce natural spawning in February 25, 1994 and February 16 to 24, 1995. They were already matured when stocked, and average body length (50.66 cm) and body weight (1,192.74 g) of 57 females and average body length (48.62 cm) and body weight (612.58g) of 43 males were recorded. Before stocking, they were inserted with identification tags(ID tags) in the dorsal muscle, and spawning was traced by the portable reader (Destron/lDl Ltd.) Forty females among 57 spawned successfully in the average of 4 days after stocking. Females spawned almost all eggs contained in the ovaries at one time in the form of an egg mass and averaging 227,200 eggs Per egg mass. The egg mass was oval in shape, translucent milky in color, 20.32cm long axis and 14.57cm short axis in size, and 803.7g in weight. Male parents guarded their egg masses and circulated water with the tail part of the body. Fertilized egg was spherical in shape, and their average diameter was 1.54 mm. Each egg had a containing single oil globule, and it's average diameter was 0.37 mm. The average water temperature was $13.2^{\circ}C$ and incubation times after fertilization were 5 hours 25 minutes up to 2-cell stage, 13 hours up to morula stage, and 66 hours 35 minutes up to embryo formation stage. Hatching rate was approximately 10 percent in 368 hours 50 minutes after fertilization, and approxionateoly 90 percent of eggs were hatched in 425 hours 30 minutes after fertilization.

• Journal of the korean Society of Automotive Engineers
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• v.7 no.1
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• pp.12-17
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• 1985

주위기체와 다른 기체를 간헐적으로 또는 단발로 분사한 경우, 분류내의 분사체의 농도는 시간에 따라 급격히 변화한다. 수ms인 전자식기체 채취밸브를 이용해서 기체를 채취하고, 가스마토그 라프 등에 의해 가스분석을 행하는 방법이 있고 주로 피스톤식 내연기관의 연소실내 농도의 측 정에 이용되고 있다. 이 방법은 밸브 열립시간을 단축시켜도 약 1ms가 한도이고 시간분해능력도 1ms정도가 최단시간이다. 또 동일한 장소에서 농도의 시간경과를 얻는 데에는 각각의 시간에 대해서 기체의 채취와 분석을 행하지 않으면 안되어 실제시간의 농도측정이 불가능하다는 결점이 있다. 최근 레이저 응용기술의 진보에 의해 라만산란, 레리산란, CARS법 등의 농도순간측정이 가능해지고 있고, 점차 현실화되어가고 있다. 이들의 방법은 국소의 순간농도뿐만 아니라 온도의 동시측정도 가능하게 하는 특징을 갖고있다. 그러나 레이저에 의한 측정장치는 현시정에서는 아직 가격이 고가이고 광학계의 설치 등, 실험상의 조작이 복잡한 것 등의 결점을 갖고 있다. 본 고에서는 최근 진전이 현저하고 실용화에 대한 확신을 갖고 있는 열선농도Probe에 의한 순간농 도의 측정방법을 소개하고자 한다.

• Proceedings of the KSRS Conference
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• 2006.03a
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• pp.145-148
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• 2006

새로 조성된 간척지 갯벌이 건조 수축하면 지반 침하와 더불어 토양 내로의 마이크로파의 침투 깊이가 증가한다 따라서 인공위성 DInSAR를 이용하여 지반 침하량을 구하고자 할 때, 건조 시 동시에 발생하는 마이크로파의 개펄 침투 현상을 규명하여 보정해 주어야 한다. 이를 위하여 다편광 산란계(Polarimetric Scatterometer)를 구성하여 건조 개펄에 대한 실내실험을 실시하였다. PolScat의 구성은 5.0-5.6GHz 대역의 dual-polarization square horn antenna를 사용하였으며 Agilent 8753ES 벡터 네트워크 분석기를 사용하였다. 길이 2m, 폭 2m, 높이 20cm의 개펄 샘플을 약 6주 동안 실내에서 건조시켜 위상을 측정한 결과 지반 침하와 함께 약 4mm의 마이크로파 투과현상이 발견되었다. 따라서 인공위성 DInSAR 지반침하량 계산에 있어서 반드시 토양 수분에 따른 마이크로파의 토양 침투 깊이를 보정해 주어야 함이 밝혀졌다.

• Korean Journal of Ichthyology
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• v.23 no.3
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• pp.246-249
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• 2011

Twenty five specimens (40.8~58.4 mm SL) of Gymnogobius taranetzi (Family Gobiidae) were collected from the estuary of Samcheok-si and Yangyang-gun, Gangwon-do, Korea. This species is distinguished from other Gymnogobius species by oculoscapular canals not extending anteriorly through interorbital space, but replaced by rows of sensory papillae; oculoscapular canal pore C is absent; some yellow bands on body in female with breeding color. The new Korean name "Dong-hae-nal-mang-duk" is proposed for this species.