Chuuk Lagoon애 서식하는 흑진주조개, Pinctada margaritifera (Linnaeus 1758)의 2003년 하계 생식소 발달 및 산란 특성

강도형,이순길,최광식,박흥식 한국해양과학기술원 2005 Ocean and Polar Research Vol.27 No.3

Reproductive condition of the tropical blacklip pearl oyster, Pinctada margaritifera collected during the period July through September 2003 from Chuuk Lagoon, Federated State of Micronesia was investigated using histology. The level of gonad development for each pearl oyster was determined with an average score of five microscopic fields, and the average score was used as the maturity index (MI). All wild pearl oysters collected in July did exhibit fully ripe eggs in their ovaries (45~50 m in diameter), indicating that they were ready for spawning. In mid August, most wild pearl oysters were in spawning and MI dropped dramatically from mid- to late September, suggesting that the wild pearl oyster completed spawning during this period. In contrast, the cultivated pearl oysters collected in mid-September held ripe eggs in the ovaries and only a few of them spawned, indicating that gonad maturation of the cultivated pearl oyster was somewhat slower than that of the wild pearl oyster in Chuuk Lagoon during the summer period. Histological analysis also indicated that spawning of the pearl oyster is rather incomplete and they may spawn continuously during summer.

추자도산 홍합, Mytilus coruscus (Gould, 1861) 의 Condition Index 산정에 대한 연구

강도형,최광식 한국패류학회 1999 The Korean Journal of Malacology Vol.15 No.1

Condition indices (Cl) are considered to be useful measurements of the nutritive and health status of bivalves although studies on Cl of bivalves are limited due to the lack of a standard formula for calculating Cl. This study attempts to generate Cl of the mussel, Mytilus coruscus inhabiting along the coastal area of Chuja Island in Cheju using three primary formulas. the formulas used in this study: (1) Cl-vol= [tissue dry weight (g) 1000] /shell cavity volume (ml). (2) Cl-wt= [tissue dry weight (g) 1000] / internal shell cavity capacity (g). (3) Cl-size= tissue wet weight (g)/[shell length (mm)]$\^$3/. Monthly condition indices calculated with the three formulas are compared using ANOVA, Duncan's multiple range test and Pearson correlation coefficient. In Chuja Island M. coruscus collected ranged from 50 to 180 mm in shell length. Monthly ranges of Cl-values were 67.48 to 140.61 (Cl-vol), 74.67 to 118.02 (Cl-wt) and 1.4 10$\^$-5) to 1.6 10$\^$-5/ (Cl-size). Cl-vol values in August were higher than two Cl-values in the other months. Monthly Cl-vol was significantly different from Cl-wt and Cl-size. (p<0.05). The results of this study suggest that volumetric condition index (Cl-vol) used in this study is acceptable as a standard measure to evaluate conditions of M. coruscus.

제주도 함덕 연안에 서식하는 구멍연잎성게, Astriclypeus manni (VERRIL 1867)의 생태학적 특성에 관한 연구

강도형,최광식,정상철,KANG DO-Hyung,CHOI Kwang-Sik,CHUNG Sang-Chul 한국수산과학회 1999 한국수산과학회지 Vol.32 No.3

The sand dollar, Astriclypeus manni is commonly encountered on a subtidal sand bottom along the coast of Cheju Island. limited information has been reported on their ecology despite their natural abundance. This study reports ecology and an annual reproductive cycle of the sand dollars present at Hamdock, northern coast of Cheju Island. A. manni collected from Hamdock revealed that they are 80 to 200 mm in test diameter. Sediment Brain size analysis indicated that A. manni mostly occurs on medium (particle diameter of 500 $\mu$m) to very find sand (particle diameter of 125 $\mu$m), particularly on fine sand (particle diameter of 250 $\mu$m). Internal morphology and in situ observations on their feeding habit indicated that A. manni is a deposit feeder, feeding on organic debris contained in the sediment around its habitat. A. manni were more frequently observed near Zostrea marina bed where content of organic matter in the sediment is considered to be higher. Gonadal tissues of the male were yellow in color while female gonads appeared to be purple. Fully mature eggs, with a mean diameter of 381 $\mu$m, and sperm were observed from the histological slides of the sand dollars collected in late July to August, suggesting that A. manni spawn during July to August when water temperature reaches 20 to $25^{\circ}C$.

마이크로 혼합기와 반응기로 구성된 DNA 결찰용 바이오칩에 관한 연구

강도형,안유민,황승용,Kang, Do-Hyoung,Ahn, Yoo-Min,Hwang, Seung-Yong 대한기계학회 2008 대한기계학회논문집 Vol.32 No.8

In this research, we developed new PDMS-glass based microbiochip consisted of the micromixer and microreactor for DNA ligation. The micromixer was composed of a straight channel integrated with nozzles and pillars, and the microreactor was composed of a serpentine channel. We coated the PDMS chip surface with the 0.25wt.% PVP solution to prevent the bubble generation which was caused by the hydrophobicity of the PDMS. The new micomixer was passive type and the mixing was enhanced by a convective diffusion using the nozzle and pillar. The 10.33mm long micromixer showed the good mixing efficiency of 87.7% at 500 l/min flow rate. We could perform the DNA ligation successfully in the microbiochip, and the ligation time was shortened from 4 hours in conventional laboratory method to 5 min in the microbiochip.

해양수산생명산업 분야 미래를 논하다

강도형 제주학회 2022 제주학회 학술발표논문집 Vol.2022 No.2

미세조류 바이오연료 상용화를 위한 주요 인자 연구

강도형,허수진,오철홍,주세종,전선미,최현우,노재훈,박세헌,김태영 한국해양과학기술원 2012 Ocean and Polar Research Vol.34 No.4

Microalgae are photosynthetic microorganisms that are highly productive in the presence of basic renewable natural sources (light, CO2, water and nutrients). They can synthesize lipids, carbohydrates and proteins in a small number of days. Subsequently, these carbon-captured products can be processed into both biofuels and valuable co-products. Additionally, microalgae would be an ideal feedstock for replacing land-based food crops with cellular products as high energy density transportation fuels. These microscopic organisms could contribute a significant amount of renewable energy on a global scale. In Korea, microalgae biofuel research was common in the early 1990s. The research activities were unfortunately stopped due to limited governmental funds and low petroleum prices. Interest in algal biofuels in Korea has been growing recently due to an increased concern over oil prices, energy security, greenhouse gas emissions, and the potential for other biofuel feedstock to compete for limited agricultural resources. The high productivity of microalgae suggests that much of the Korean transportation fuel requirements can be met by biofuels at a production cost competitive with the increasing cost of petroleum seen in early 2008. At this time, the development of microlalgal biomass production technology remains in its infancy. This study reviewed microalgae culture systems and biomass production, harvesting, oil extraction, conversion, and technoeconomical bottlenecks. Many technical and economic barriers to using microalgal biofuels need to be overcome before mass production of microalgal-derived fuel substitutes is possible. However, serious efforts to overcome these barriers could become a large-scale commercial reality. Overall, this study provides a brief overview of the past few decades of global microalgal research.

제주도 문섬 조하대에 서식하는 연산호군락의 태풍에 의한 영향 분석

강도형,송준임,최광식 한국해양과학기술원 2005 Ocean and Polar Research Vol.27 No.1

Impacts of Typhoon Maemi on a soft-coral community located on subtidal cliff at Munseom, Jeju were investigated in this study using underwater photography. Typhoon Maemi hit Jeju Island in late September 2003 and its impact was strong enough to destruct most shallow water sessile benthos including soft corals. To estimate numbers and size of soft-coral colonies, a line transect was installed on the cliff at depth from 3 to 9 m and photographs were taken serially by every 1 m. From each 1 1 m underwater photograph, species and size of soft-coral colony was determined. Number of soft-coral colony and its percent coverage (PC) in each 1 m2 quadrat was calculated. Soft corals Scleronephthya gracillimum, Dendronephthya gigantea, D. putteri, D. spinulosa and D. castanea were identified from the photographs. Dendronephthya sp. was mainly distributed at 3-6 m while S. gracillimum was mostly occurred at 6~9 m. A survey conducted before the typhoon showed that number of the soft-coral colonies at 3~4 m, 4~5 m, 5~6 m, 6~7 m, 7~8 m and 8~9 m was 17, 24, 20, 23, 18 and 30 colonies/m2 or 21, 48, 36, 28, 24 and 43%, respectively. After the typhoon, number of soft-coral colonies in the transect increased, 31, 35, 27, 10, 21 and 50 colonies/m2 while PC was remarkably decreased as 21, 23, 21, 5, 9 and 13%, respectively. Our data suggested that the impact was limited in larger colonies; larger soft coral colonies were selectively destroyed and removed while the small colonies underneath the larger colonies remained undestroyed.

육각형 질화붕소를 첨가한 고분자분리막의 가스분리성능 개선

강도형,박찬우,송승현,정유담,아흐마드이샤크,지호빈,양은태 한국막학회 2024 한국막학회 총회 및 학술발표회 Vol.2024 No.11

RCD 스너버 및 준구형파를 이용한 250[W] HPS lamp용 전자석 안정기 개발

강도형,박종연 한국조명전기설비학회 2002 조명·전기설비학회논문지 Vol.16 No.2

본 논문은 고압 방전램프를 점등시켜 주는 전자식 안정기에 관한 것으로서, Class D LCC 공진 인버터 방식을 이용하여, 램프의 초기 점등, 정상상태를 구동하게 하고, 준구형파로 ZC-ZVS Soft Switching을 구현하여 풀-브리지 스위치의 발열을 최소화할 수 있도록 하였다. 또한, RCD 스너버 회로를 적용하여 스위치 발열 감소뿐만 아니라, 고주파 스위칭으로 인한 서지 전압의 감소를 통한 노이즈를 최소화시켜 제어부의 안정되고, 신뢰성 있는 동작을 가능하게 할 수 있도록 하고, 안정기의 전체적인 스위칭 노이즈 발생을 최소화하였다. In this paper, We have researched about the Electronic Ballast for 250W HPS(High Pressure Sodium) lamp. This Electronic Ballast is capable to operate the Ignition and Steady State Using the Class D LCC resonant tank, and minimizing the full-bridge inverter's Switching Stress by implementation Quasi-square ZC-ZVS Soft Switching Method. And also, We have reduced the heat of MOS-FETs and high frequency switching surge noise using the RCD damp snubber. Therefore, We are sure that the developed ballast has the properties of the stable & reliable Control and the function of minimizing the total noise of the system.

용융 촉매를 활용한 메탄 전환

강도형 한국공업화학회 2024 한국공업화학회 연구논문 초록집 Vol.2024 No.1