• Title/Summary/Keyword: elongated field

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NUMERICAL STUDY ON FLOW OVER CIRCULAR CYLINDER USING NO SLIP BOUNDARY TREATMENT (점착경계처리법을 이용한 원형실린더 주위의 유동해석)

  • Kang Jung-Ho;Kim Hyung-Min
    • Journal of computational fluids engineering
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    • v.11 no.3 s.34
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    • pp.28-36
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    • 2006
  • NSBT(No Slip Boundary Treatment) is a newly developed scheme for the treatment of a no slip condition on the solid wall of obstacle in a flow field. In our research, NSBT was used to perform LBM simulation of a flow over a circular cylinder to determine the flow feature and aerodynamics characteristic of the cylinder. To ascertain the applicability of NSBT on the complex shape of the obstacle, it was first simulated for the case of the flow over a circular and square cylinder in a channel and the results were compared against the solution of Navier-Stokes equation. The simulations were performed in a moderate range of Reynolds number at each cylinder position to identify the flow feature and aerodynamic characteristics of circular cylinder in a channel. The drag coefficients of the cylinder were calculated from the simulation results. We have numerically confirmed that the critical reynolds number for vortex shedding is in the range of 200$\sim$250. For the gap parameter $\gamma$ = 2 cases at Re > 240, the vortex shedding were symmetric and it resembled the Karmann vortex. As the cylinder approached to one wall, the vorticity significantly reduced in length while the vorticity on the other side elongated and the vorticity combined with the wall boundary-layer vorticity. The resultant $C_d$ by LBM concurred with the results of DNS simulation performed by previous researchers.

Functional Anatomy and Histology of the Olfactory Organ in Korean Eel Goby, Odontamblyopus lacepedii (Pisces: Gobiidae)

  • Kim, Hyun Tae;Lee, Yong Joo;Park, Jong Young
    • Applied Microscopy
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    • v.48 no.1
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    • pp.11-16
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    • 2018
  • For Odontamblyopus lacepedii with small and turbid eyes, the gross structure and histology of the olfactory organ, which is important for its survival and protection of the receptor neuron in estuarial environment and its ecological habit, was investigated using a stereo, light and scanning electron microscopes. Externally, the paired olfactory organs with two nostrils are located identically on each side of the snout. These nostrils are positioned at the anterior tip of the upper lip (anterior nostril) and just below eyes covered with the epidermis (posterior nostril). Internally, this is built of an elongated olfactory chamber and two accessory nasal sacs. In histology, the olfactory chamber is elliptical in shape, and lined by the sensory epithelium and the non-sensory epithelium. The sensory epithelium of a pseudostratified layer consists of olfactory receptor neurons, supporting cells, basal cells and lymphatic cells. The non-sensory epithelium of a stratified layer has swollen stratified epithelial cells and mucous cells with acidic and neutral sulfomucin. From these results, we confirmed the olfactory organ of O. lacepedii is adapted to its ecological habit as well as its habitat with burrows at the muddy field with standing and murky waters.

In vitro Multiple Shoot Proliferation and Plant Regeneration of Vanilla planifolia Andr. - A Commercial Spicy Orchid

  • Gopi C.;Vatsala T.M.;Ponmurugan P.
    • Journal of Plant Biotechnology
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    • v.8 no.1
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    • pp.37-41
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    • 2006
  • In vitro mass multiplication of Vanilla planifolia was investigated using node as explant. Multiple shoots were developed in MS medium supplemented with $2.0mgl^{-1}$ 6-benzylaminopurine and $1.0mgl^{-1}$ $\alpha$-naphthalene acetic acid. Multiple shoots were maintained for 6-T weeks with regular subculturing at the end of $3^{rd}$ week onto fresh medium. The maximum number of shoots at the rate of 12.8 per node segment was achieved over a period of four weeks. The elongated shoots were separated from the shoot clusters and were transferred onto half strength MS medium supplemented with indole-3-acetic acid ($1.0mgl^{-1}$) over a period of 28 days for induction of roots. The development of roots was observed on $7^{th}$ day of incubation. The in vitro raised plantlets were transferred to poly-cups, covered with polyethylene sheets and maintained under shade net for 25 days for hardening. Finally these plants were transferred to field and recorded that 85 % of tissue cultured plants were survived. From the present study, a simple and efficient micropropagation protocol was developed for Vanilla planifolia using single node segments as explants.

A strategy to enhance the efficiency of land seismic reflection method via controlling seismic energy radiation pattern. (지면 탄성파 반사법의 효율성 향상을 위한 탄성파 발생원 에너지 방사형 변조기법)

  • Kim, Jung-Yul;Kim, Yoo-Sung
    • Proceedings of the Korean Geotechical Society Conference
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    • 2004.03b
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    • pp.807-814
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    • 2004
  • Land seismic reflection survey has been increasingly demanded in various civil engineering works because of its own ability to delineate layers, water table, to detect cavities or fracture zones, to estimate seismic velocities of each layer. However, our shallow subsurface structures are very complex. The relatively thin layer(mostly soil) to the wavelength directly followed by a basic rock with high impedance used to generate complicated surface waves, kind of channel waves with high amplitude that is dominate in entire seismograms and hence the useful reflection events will be almost hopelessly immersed in the undesired surface waves. Thus, it would seem that the use of traditional seismic survey could not be likely to provide in itself a satisfactory information about our exploration targets. This paper hence introduces an efficient measuring strategy illustrating a properly controlled arrangement of the vertical single force sources commonly used, yielding a very sharply elongated form of P-energy with a minimum of S radiation energy, what we call, P-beam source. Abundant experiments of physical modeling showed that in that way the surface waves could be enormously reduced and the reflection events would be additive and thus reinforced. Examples of field data are also illustrated. The contribution of P-beam source will be great in civil engineering area as well as in general geological exploration area.

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Occurrences of Asbestos within Gapyeong Serpentinite Mines and Characteristics of Host Rocks (가평 사문암 광산의 석면 산출의 산상과 모암의 특성)

  • Song, Suckhwan;Kang, Joongu
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.26 no.3
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    • pp.253-266
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    • 2016
  • Objectives: This study is for characteristics of asbestos occurrence (NOA, naturally occurring asbestos) from the Gapyeong area and its host rocks, serpentinites. Methods: Representative samples are collected from the serpentinite bodies, following degrees of hydrothermal alteration and metamorphism, after about 2 year field trips. Mineralogical, morphological and optical characteristics of the asbestos and host rocks are confirmed by PLM, XRD EPMA and SEM results. Results: The serpentinites are dunites and harzburgites, and host asbestos, including chrysotile, tremolite and actinolite. The asbestos chrysotiles are found as veins ranging from several millimeters to several centimeters in thickness, while asbestos-tremolite and -actinolite occur along cracks and fractures ranging up to ten centimeters in thickness. The chryostiles occur mainly as cross and slip fibers, while the amphibole asbestos is found as vein, slip and oblique fibers. More tremolitic grains are colorless and commonly show elongated or fiber shapes, whereas the magnesio hornblende grains mainly show light green and occur as subhedral to euhedral diamond grains. Conclusions: Overall characteristics of serpentinites from the Gapyeong area are similar to worldwide orogenic-related Alpine type ultramafic rocks serpentinized and serpentinites in South Chungcheong-do Province, Korea, and occurrences of asbestos are similar to those of the ultramafic bodies in South Chungcheong-do Province.

Effect of Fungicide Benoram Seed Treatment on Germination, Growth, and Yield in Summer-Type Soybean (종자소독제 Benoram 처리가 하대두의 발아, 후기생육 및 수량에 미치는 영향)

  • 정길웅;주정일
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.38 no.2
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    • pp.166-173
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    • 1993
  • Seed infection to pod and stem blight (Diaporthe phaseolorum) is severe at summer type soybeans maturing at hot and humid conditions. In order to increase germination and plant stand, this experiments were evaluated the effects of fungicide Benoram(Benomyl 20% ${\pm}$ Thiram 20%) seed treatments with different seed sizes on emergence yield at field conditions, and with different infection degrees to pod and stem blight on germination in laboratory. Benoram treatment on seed was improved emergence rate and elongated hypocotyl not increased growth and yield. It was clearly improved length but germinations and germination speed by Benoram fungicide treatment on severely infected seed however was not improved germination rate at good quality of seeds and the effect was higher at large seed cultivar than small ones.

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Evaluation of fracture density distribution for the design of grouting works in fractured rocks (그라우팅 설계를 위한 절리밀도분포 산출법 개발)

  • 김중열;김유성
    • Proceedings of the Korean Geotechical Society Conference
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    • 2002.03a
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    • pp.627-634
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    • 2002
  • To facilitate a drilling plan for grouting in fractured rock, an algorithm of practical use associated with a new term “fracture density distribution”or“fracture tomogram”is developed. It is well known that Televiewer data(amplitude and traveltime image) provide detailed information about not only dip and dip direction of each fracture but also its aperture size estimated by an appropriate evaluation algorithm. A selected plane section of medium around a borehole or the cross section between two boreholes is discretized into a two dimensional grid of cells(rectangular elements). As each elongated(straight) fracture passes through the cells, the corresponding aperture size value is successively summed up in each cell, depending on the fracture length segment. In this, the fracture lines can be determined by intersecting of each fracture plane with the selected plane section. If the fracture line does not pass through a particular grid element, the segment length is set to zero. The final value(aperture size value of each cell) derived from all the detected fractures constitutes the fracture density distribution of the selected plane section, Field examples are illustrated, which will prove the benefit of the suggested algorithm for several kinds of grouting works.

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Preliminary Study of Effect of Internal Wave to Phytoplankton Distribution in the Lombok Strait and Adjacent Areas

  • Arvelyna, Yessy;Oshima, Masaki
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1246-1248
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    • 2003
  • Internal wave with a soliton-like, large amplitudes within several kilometers, is frequently observed in the sea surface caused by tidal rectification due to sill or rough topographic changes. Internal waves can perturb current and density field, initiate bottom sediment re -suspension and mix nutrients to photic zone. Previous studies indicate that the appearance of internal wave in the Lombok Strait have been detected in SAR image data. This paper studies effect of internal wave in the Lombok Strait to chlorophyll distribution in the surrounded areas using SeaWiFS and ERS SAR images data during 1996-2001 periods. The preliminary result concludes that the internal waves presumably affect phytoplankton distribution spreading southeastward in the coast off Bali Island. The distribution of phytoplankton at southern coastline off Bali Island when internal wave occurred is elongated and distributed further to westward (from 8.8$^{\circ}$ to 10.7$^{\circ}$LS) than the area when internal wave did not occur on August 2000 (from 9.25$^{\circ}$ to 10.25$^{\circ}$LS) as shown in figure 3. It shown that the surface phytoplankton concentration near coastal area, i.e. from 8.8$^{\circ}$ to 9.25$^{\circ}$ LS, increased when internal wave is occurred.

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Mastopexy Performed in a Liver Transplantation Recipient: A Case Report (간이식 수용자에서 시행한 유방 고정술의 증례보고)

  • Lee, Kang-Woo;Lee, Taik-Jong
    • Archives of Plastic Surgery
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    • v.38 no.4
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    • pp.527-530
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    • 2011
  • Purpose: Liver transplantation is a groundbreaking section in the field of surgery. Nowadays over 90% of success rate is accomplished and life expectancy of the patients has been elongated. Patients are now seeking for surgical procedures including cosmetic plastic surgery. But these patients take immunosuppressive medication and steroids, which can increase the risk of wound infection, and delay wound healing. By reviewing the case of a 21-year-old liver transplant recipient who underwent mastopexy due to breast ptosis, we discussed about the matters we should consider when performing surgery in liver transplantation recipients. Methods: The patient was a 21-year-old female who received liver transplantation from her father. She was exposed to massive amount of steroids and immunosuppressants, which led to breast ptosis. The vertical and short horizontal incision mastopexy using a medial-based pedicle was done, 29 months after the liver transplantation. Results: On postoperative day 1, she was discharged. On day 10, sutures were removed and taping was applied. There was no sign of wound infection, wound dehiscence, hematoma or bleeding. The patient was followed up at 3, 6 and 9 months after the operation. Mild recurrence of the glandular ptosis was observed but revision was not required. Conclusion: We were able to successfully operate without any complications in the liver transplant recipient. With special attention and consideration, cosmetic plastic surgery can be safely performed in organ transplantation recipients.

Spinal Cord Partial Block Technique Using Dynamic MLC

  • Cho, Sam-Ju;Yi, Byong-Yong;Back, Geum-Mun;Lee, Sang wook;Ahn, Seung-Do;Kim, Jong-Hoon;Kwon, Soo-Il;Park, Eun-Kyung
    • Proceedings of the Korean Society of Medical Physics Conference
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    • 2002.09a
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    • pp.138-140
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    • 2002
  • The spinal cord dose is the one of the limiting factor for the radiation treatment of the head & neck (H&N) or the thorax region. Due to the fact that the cord is the elongated shaped structure, it is not an easy task to maintain the cord dose within the clinically acceptable dose range. To overcome this problem, the spinal cord partial block technique (PBT) with the dynamic Multi-Leaf Collimator (dMLC) has been developed. Three dimension (3D) conformal beam directions, which minimize the coverage of the normal organs such as the lung and the parotid gland, were chosen. The PBT field shape for each field was designed to shield the spinal cord with the dMLC. The transmission factors were determined by the forward calculation method. The plan comparisons between the conventional 3D conformal therapy plan and the PTB plan were performed to evaluate the validity of this technique. The conformity index (CI) and the dose volume histogram (DVH) were used as the plan comparison indices. A series of quality assurance (QA) was performed to guarantee the reliable treatment. The QA consisted of the film dosimetry for the verification of the dose distribution and the point measurements. The PBT plan always generated better results than the conventional 3D conformal plan. The PBT was proved to be useful for the H&N and thorax region.

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