• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.8 s.239
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• pp.911-920
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• 2005

The present study investigates heat/mass transfer and flow characteristics in a ribbed rotating passage with turning region. The duct has an aspect ratio (W/H) of 0.5 and a hydraulic diameter ($D_h$) of 26.67 mm. Rib turbulators are attached in the parallel arrangement on the leading and trailing surfaces of the passage. The ribs have a rectangular cross section of 2 m (e) $\times$ 3 m (w) and an attack angle of $70^{\circ}$. The pitch-to-rib height ratio (p/e) is 7.5, and the rib height-to-hydraulic diameter ratio (e/$D_h$) is 0.075. The rotation number ranges from 0.0 to 0.20 while the Reynolds number is constant at 10,000. To verify the heat/mass transfer augmentation, internal flow structures are calculated for the same conditions using a commercial code FLUENT 6.1. The results show that a pair of vortex cells are generated due to the symmetric geometry of the rib arrangement, and heat/mass transfer is augmented up to $Sh/Sh_0=2.9$ averagely, which is higher than that of the cross-ribbed case presented in the previous study for the stationary case. With the passage rotation, the main flow in the first-pass deflects toward the trailing surface and the heat transfer is enhanced on the trailing surface. In the second-pass, the flow enlarges the vortex cell close to the leading surface, and the small vortex cell on the trailing surface side contracts to disappear as the passage rotates faster. At the highest rotation number ($R_O=0.20$), the turn-induced single vortex cell becomes identical regardless of the rib configuration so that similar local heat/mass transfer distributions are observed in the fuming region for the cross- and parallel-ribbed case.

• Journal of Environmental Science International
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• v.18 no.10
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• pp.1163-1170
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• 2009

The clam, Gomphina melanaegis, which is commonly called the sandy beach clam because of its habitat, is a valuable organism in the sandy coast of East Sea, Korea. It is frequently observed in large populations between 0.5 and 5 meters. We have released 50,000 seedling, ranging from the diameter of approximately 3 mm, 2007, and 1,000,000 seedling, ranging from the diameter of approximately 0.2 mm, plus 100,000 adult individuals, ranging from the shell length of approximately 20~40 mm, 2008 at Jinha beach. The spawning period of G. melanaegis, was from June to August, and the main spawning occurred in July. This investigation was carried out to elucidate population distribution on the stocking area of sandy beach clam, G. melanaegis. The relationship between shell length and ring radius in each ring was investigated as a regression line. The relationship between the shell length and shell height of released young clam was SH=1.0105SL-4.7764 ($R^2=0.7905$). The relationship between the shell length and total weight of released young clam was $TW=0.0013SL^{2.3966}$($R^2=0.71$). It draws a deduction that the ring of this clam was produced once a year during the duration between June and August.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.33-34
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• 2019

Malaysia, as a tropical rainforest country, enjoys an abundance of bamboo plant that proliferate throughout the country. The application of geopolymer technology has become a trend and preserve the environment from harm. Fly ash geopolymer concrete has low early strength and requires 24 hours for the concrete to harden. Thus, the presence of calcium and potassium content in bamboo ash could remedy this problem. Besides, there is no research regarding the use of bamboo ash as a binder in geopolymer concrete. Therefore, the presence of bamboo ash could improve the research field with the use of agriculture waste in a building construction. This research aim is to use bamboo ash in the production of fly ash geopolymer concrete. The specimens were casted in $100mm{\times}100mm{\times}100mm$ cubes and sodium based activator were used as the alkaline solutions. The binders are formulated with different binder ratio. All test specimens were cured at ambient temperature ($23^{\circ}C-25^{\circ}C$) and 100% fly ash was chosen as control specimen. To determine the mechanical properties of fly sh geopolymer concrete with the presence of bamboo ash, compressive strength test was conducted. The test results depicted that as the percentage of bamboo ash decreases, compressive strength increases. Also, the addition of 5% of bamboo ash into fly ash geopolymer concrete could improve the early strength in 7 days. The results were proven with the result explained by X-ray fluorescence (XRF) and X-ray diffraction (XRD). Therefore, it can be concluded that the addition of bamboo ash improved the properties of fly ash geopolymer concrete at early ages.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.4
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• pp.206-216
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• 1988

In order to set up a predictive model for effective spat collection of pen shell, Atrina (Servatrina) pectinata, the survival rate and time required at each developmental stage of drifting larvae were surveyed during the period from June 8 to October 16 in 1986 at the Yongku inlet Chilchon Is., Chinhae Bay, the southern part of Korea. And also the experiments of spat collection were carried out In Yongku inlet during the period from July 6 to November 23 in 1987 and In Yoja Bay during the period from July 9 in 1987 to February 15 in 1588. The advent of D-shape larvae ca. $135\times144um $ long had three peaks in that area: August 1, 12 and 25. Umbo shape larvae ca. $300\times317um$ and full grown larvae ca. $455\times450um$ long also sowed three peaks: August 9, August 22 and September 4 for the former, and August 23, September 3 and September 16 for the latter. Nine to ten days was required for D-shape larvae to develop to umbo shape larvae. The instantaneous survival rate was 0.94 with a total survival rate if $54\%$ at this intermorphological stage. The required time of umbo to full grown larvae varied from twelve to fourteen days with a instantaneous survival rate of 0.88 and total survival rate of $19\%$. Twenty-two to twenty-three days was required for each group of the D-shape larvae to reach a fullgrown stage, and their total survival rate was $10\%$ during this developmental period. The number of the spat attached to the spat collector is 0.16 inds. per $m^2$ vertical spat collector in Yongku inlet and 0.48 inds. per $m^2$ horizontal spat collector in Yoja Bay. The average shell length of spat attached was $0.51({\pm}0.15)\;mm$ on September $27,\;38.52({\pm}6.98)\;mm$ on November 21 in 1987 and $49.00({\pm}10.77)mm$ on February 15 in 1988.

• Korean Journal of Plant Tissue Culture
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• v.26 no.4
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• pp.251-257
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• 1999

Adventitious buds were produced from the cultures of mature zygotic embryos of Larix leptolepis with the highest frequency of 91.7% in SH medium containing 1.0 mg/L zeatin. The most effective cytokinin combination for inducing adventitious buds was 1.0 mg/L zeatin + 1.0 mg/L thidiazuron (40.3%). The highest mean number of adventitious buds induced in 1.0 mg/L zeatin + 1.0 mg/L 2iP or 1.0 mg/L zeatin + 1.0 mg/L kinetin combined treatments. Elongation of the adventitious buds occurred the best on half strength LM salts medium, on which the buds elongated upto 27 mm. Also, the supplement of activated charcoal in medium suppressed the elongation of the adventitious buds. The highest frequency (23.3%) of rooting from elongated shoots was obtained on the medium containing 5.0 mg/L IBA and 0.2 mg/L NAA. The highest number (3.5) of roots was induced on the medium containing 5.0 mg/L IBA alone.

• Journal of Marine Life Science
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• v.6 no.2
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• pp.88-96
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• 2021

The purpose of this study was to report the intersex identified in the oyster Crassostrea gigas (n=410, SH 43.3±11.4 mm) in the waters around 13 uninhabited islands near Yeosu. The overall sex ratio (male: female) was 1:1.1, but there was a difference between the sampling areas. In Gajangdo, Sogyeongdo, and Jungsamdo, females showed a high ratio of 65% or more, and in Songdo, Chodo, and Buseodo, males showed a high ratio of 65% or more. The overall intersexuality was about 12.8%, which was high in males, about 34.7% in females and 64.3% in males. Intersexuality was the highest with about 43.8% in Chodo of Gamak Bay. Histologically, intersex could be divided into three types: intrafollicular type, interfollicular type and mixed type. Among these three types, the intrafollicular type was the most dominant with about 81.6%. The intersex cause of oysters reported in this study is considered to require detailed research in the future.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.4 s.235
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• pp.485-494
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• 2005

For the extensive investigation of local heat/mass transfer on the near-tip surface of turbine blade, experiments were conducted in a low speed stationary annular cascade. The turbine test section has a single stage composed of sixteen guide vanes and blades. The chord length and the height of the tested blade are 150 mm and about 125 mm, respectively. The blade has flat tip geometry and the mean tip clearance is about $2.5{\%}$ of the blade chord. Detailed mass transfer coefficient on the blade near-tip surface was obtained using a naphthalene sublimation technique. The inlet flow Reynolds number based on chord length and incoming flow velocity is changed from $1.0{\times}10^{5}\;to\;2.3{\times}10^{5}.$ Extremely complex heat transfer characteristics are observed on the blade surface due, to complicated flow patterns, such as flow acceleration, laminarization, transition, separation bubble and tip leakage flow. Especially, the suction side surface of the blade has higher heat/mass transfer coefficients and more complex distribution than the pressure side surface, which is related to the leakage flow. For all the tested Reynolds numbers, the heat/mass transfer characteristics on the turbine blade are the similar. The overall averaged $Sh_{c}$ values are proportional to $Re_{c}^{0.5}$ on the stagnation region and the laminar flow region such as the pressure side surface. However, since the flow is fully turbulent in the near-tip region, the heat/mass transfer coefficients are proportional to $Re_{c}^{0.8}.$

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2009.05a
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• pp.173-176
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• 2009

국가 과학기술 경쟁력 재고를 위하여 R&D기관에서 생성되는 연구데이터를 종합적으로 관리하고 서비스하는 데이터 관리/서비스 시스템의 개발의 필요성이 증대되고 있다. 이에 따라 본 연구에서는 VKH (Visible Korean Human) 데이터를 3차원으로 시각화 서비스하는 플랫폼을 제안하고 구현한다. VKH 데이터는 사망과 동시에 급속 냉동한 인간의 신체를 0.2mm 간격으로 절단하며 촬영한 방대한 양의 실사 이미지 데이터베이스이며, 전통적인 생물학, 의학 분야의 연구뿐만 아니라, 현실감 있는 3D 이미지 구축을 위한 기반 데이터로 이용되고 있다. VKH 데이터 기반의 3D 데이터 시각화 플랫폼은 사용자 접근 편의성을 위하여 웹을 기반으로 구현되고, 트리 형식의 인체 구조 온톨로지와 연동하여 해당하는 인체 구성 요소를 체계적으로 관찰하는 기능, 사용자의 원하는 인체 구성 요소들만을 3D 화면에서 조합하고 관찰하는 기능, 위키피디아 백과사전을 참조하는 기능을 포함한다. 현재 인체의 머리 부분 3D 데이터를 대상으로 플랫폼이 구축되고 있으며, 향후 전체 인체를 대상으로 서비스할 예정이다.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.2
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• pp.129-140
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• 2008

This study was performed to estimate biomass and to provide management plan through population ecological characteristics, including growth parameters, survival rate, instantaneous coefficient of natural and fishing mortalities, and age at first capture of hen clam, Mactra chinensis, in the Dong-li self-regulatory community of Busan. The von Bertalanffy growth parameters estimated from a non-linear regression were $SH_{\infty}=86.24mm$, K=0.12/year, and = -1.37year. Survival rate(s) of the hen clam was 0.515. The instantaneous coefficients of natural mortality(M) was estimated to be 0.232/year and fishing mortality(F) 0.432/year for hen clam. The current biomass of the hen clam in the study area was estimated to be 713mt and the acceptable biological catch(ABC) was estimated under various harvest strategies based on $F_{0.1}$ and $F_{40%}$.

• Journal of Acupuncture Research
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• v.18 no.5
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• pp.135-146
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• 2001

Objective : Bone homeostasis is maintained by balance of bone formation and resorption. Therefore, bone related diseases arose by disturbance of this balance between osteoblast and osteoclast activities. To develop a successful screening system of the therapeutic components based on oriental medicine is essential to set out systematic approach for that purpose. Methods : This study was perforated Sprague-Dawley rat femur for bony defects(${\phi}5mm$) by the fissure bur. And experimetal group were treated with Cervi Pantotricuhum Cornu injection at both $Sh{\grave{e}}nsh{\tilde{u}}$(BL23) & $D{\grave{a}}zh{\grave{u}}(BL11)(0.2m{\ell})$. This was evaluated by radiography and histological analysis with in situ hybridization. Results : Cervi Pantotricuhum Cornu Herbal Acupuncture has weak effect on bony defect healing and this was evaluated by X-ray taking and histological analysis with in situ hybridization. Osteocalcin gene expression was not changed by Cervi Pantotricuhum Cornu Herbal Acupuncture in bony defects animal model. Conclusion : Taken together this study show that the Cervi Pantotricuhum Cornu herbal-acupuncture has a weak effect healing of bony defects, this type of approach might give a good chance to explore the favorable effects of Cervi Pantotricuhum Cornu herbal-acupuncture on bone tissue.