• Journal of the Society of Disaster Information
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• v.15 no.3
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• pp.402-408
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• 2019

Purpose: The study want to verify application the medium expantion foam extinguisher of expantion foam rate and fire extinguishing Performance test because the medium expansion system can maintain the discharge distance less affected by air currents, and the foam agent can be used efficiently. Method: For the study, the medium-expansion testing apparatus was manufactured and with synthetic surfactant foam agent of (class B) fire extinguishing model, and Fire Performance was analyzed for foam expansion rate and the fire agent consumption was measured and analyzed. Results: We measured the medium-spray testing apparatus and found that the expansion rate was 26.1 times. The test results of a 20-unit fire extinguishing model show that the extinguishing time is faster than the high and low foam expansion. It has been analyzed that it is possible to apply a hand-operated with a hose reel or medium expansion apparatus. Conclusion: Considering that the foaming agent and the extinguishing performance of the medium foam ratio are excellent, It is necessary to introduce the technical standards of medium foam agent for the introduction of hand-operated equipment, such as hose reel or portable medium foam apparatus.

• Korean Journal of Animal Reproduction
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• v.23 no.4
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• pp.281-291
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• 1999

The objective of this study was to optimize the freezing/thawing method of in vitro produced Hanwoo blastocysts. Day 7 blastocysts after IVF were vitrified using EFS40 (40% ethylene glycol, 18% ficoll, 0.3 M sucrose and 10% FBS added m-DPBS) as a freezing solution and electron microscope (EM) grid (V-G) or straw (V-S) as an embryo container. In both method, freezing/thawing were treated by 2-step, treatment time was required in V-G method and V-S method, for 2 min / 3 min and 3.5 min / 10 min, respectively. Embryo survival was assessed as re-expanded and hatched rates at 24 h and 48 h after warming, respectively. The results obtained in these experiments were summarized as follows: when the effect of exposure in vitrification solution and chilling injury from freezing procedure on in vitro produced expanded blastocysts were examined, at 24 h after warming, embryo survival in exposure group (100.0%) was not different compared to that in control group (100.0%), although those results were significantly different with two vitrified groups (V-G: 87.8, V-S: 77.8%) (P＜0.001). However, at 48 h after warming, hatched rates of V-G group (67.8%) were significantly higher than those of V-S group (53.3%) (P＜0.05). In addition, this hatched rate in V-G group was not different with that in exposure group (73.3%). When the effects of embryo developmental stage (early, expanded and early hatching blastocysts) and embryo container (EM grid and straw) to the in vitro survival of vitrified-warmed day 7 Hanwoo blastocysts were simultaneously examined, fast developed embryos were indicated the better resistance to freezing than delayed developed one, irrespective of embryo containers (early; 57.1 ＆ 24.4%, expanded; 84.7 ＆ 60.6%, early hatching; 91.7 ＆ 80.0%) (P＜0.001). Especially, in expanded and early hatching blastocysts, embryo survival of V-G group (67.8, 95.0%) was significantly higher than those of V-S group (53.0, 65.0%) at 48 h post warming, respectively (P＜0.05, P＜0.001). Therefore, this study indicates that Hanwoo blastocysts can be cryopreserved more simple, efficient and successful by vitrification method using EM grid.

• Polymer(Korea)
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• v.28 no.4
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• pp.321-327
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• 2004

The applications of dental restorative composite resins containing 2,2-bis [4-(2-hydroxy-3-me-thacryloyloxy propoxy) phenyl] propane as a base resin, and triethylene glycol dimethacrylate, as a diluent, were often limited in dentistry due to the relatively large amount of volumetric shrinkage that occurs during the curing reaction. In this study, in order to reduce volumetric shrinkage of the current dental restorative composite resin, asymmetric spiro orthocarbonates were synthesized and then the characteristics of resin composites containing them were explored. The volumetric shrinkage of the dental composites containing spiro orthocarbonates was decreased approximately 45%. However, the curing characteristics and mechanical properties of the new dental composites were slightly poor than those of the commercially available dental composite.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2002.11a
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• pp.535-542
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• 2002

최근 IT 산업이 급성장하면서 화상 회의, 게임, 채팅 등에서의 아바타(avatar) 제어를 위한 자연스러운 인터페이스 기술이 요구되고 있다. 본 논문에서는 동적 윤곽선 모델(active contour models; snakes)을 이용하여 복잡한 배경이 있는 컬러 CCD 카메라 영상에서 얼굴과 눈, 입, 눈썹, 코 등의 얼굴 요소에 대해 윤곽선을 추출하거나 위치를 파악하는 방법을 제안한다. 일반적으로 스네이크 알고리즘은 잡음에 민감하고 초기 모델을 어떻게 설정하는가에 따라 추출 성능이 크게 좌우되기 때문에 주로 단순한 배경의 영상에서 정면 얼굴의 추출에 사용되어왔다 본 연구에서는 이러한 단점을 파악하기 위해, 먼저 YIQ 색상 모델의 I 성분을 이용한 색상 정보와 차 영상 정보를 사용하여 얼굴의 최소 포함 사각형(minimum enclosing rectangle; MER)을 찾고, 이 얼굴 영역 내에서 기하학적인 위치 정보와 에지 정보를 이용하여 눈, 입, 눈썹, 코의 MER을 설정한다. 그런 다음, 각 요소의 MER 내에서 1차 미분과 2차 미분에 근거한 내부 에너지와 에지에 기반한 영상 에너지를 이용한 스네이크 알고리즘을 적용한다. 이때, 에지 영상에서 얼굴 주변의 복잡한 잡음을 제거하기 위하여 색상 정보 영상과 차 영상에 각각 모폴로지(morphology)의 팽창(dilation) 연산을 적용하고 이들의 AND 결합 영상에 팽창 연산을 다시 적용한 이진 영상을 필터로 사용한다. 총 7명으로부터 양 눈이 보이는 정면 유사 방향의 영상을 20장씩 취득하여 총 140장에 대해 실험한 결과, MER의 오차율은 얼굴, 눈, 입에 대해 각각 6.2%, 11.2%, 9.4%로 나타났다. 또한, 스네이크의 초기 제어점을 얼굴은 44개, 눈은 16개, 입은 24개로 지정하여 MER추출에 성공한 영상에 대해 스네이크 알고리즘을 수행한 결과, 추출된 영역의 오차율은 각각 2.2%, 2.6%, 2.5%로 나타났다.해서 Template-based reasoning 예를 보인다 본 방법론은 검색노력을 줄이고, 검색에 있어 Feasibility와 Admissibility를 보장한다.매김할 수 있는 중요한 계기가 될 것이다.재무/비재무적 지표를 고려한 인공신경망기법의 예측적중률이 높은 것으로 나타났다. 즉, 로지스틱회귀 분석의 재무적 지표모형은 훈련, 시험용이 84.45%, 85.10%인 반면, 재무/비재무적 지표모형은 84.45%, 85.08%로서 거의 동일한 예측적중률을 가졌으나 인공신경망기법 분석에서는 재무적 지표모형이 92.23%, 85.10%인 반면, 재무/비재무적 지표모형에서는 91.12%, 88.06%로서 향상된 예측적중률을 나타내었다.ting LMS according to increasing the step-size parameter $\mu$ in the experimentally computed. learning curve. Also we find that convergence speed of proposed algorithm is increased by (B+1) time proportional to B which B is the number of recycled data buffer without complexity of computation. Adaptive transversal filter with proposed data recycling buffer algorithm could efficiently reject ISI of channel and increase speed of convergence in avoidance burden of computational complexity in reality when it was experimented having the same condition of

• Journal of the Korean Wood Science and Technology
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• v.28 no.3
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• pp.1-8
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• 2000

To develop the technology of producing structural board from low grade materials, an attempt was made to produce strand/particle composites from split wood strand(S) and particle(P) of (Cryptomeria japonica D. Don), which changed the layer construction and the ratio of S/P. The influence of layer construction on board properties was determined, focusing on the number and alignment of the S layers. The effect of weight ratio of S/P (3:7, 1:1, 7:3) on mechanical properties was also discussed on seven layered panel. Mechanical properties were determined from static bending tests to give parallel and perpendicular modulus of rupture (MOR) and modulus of elasticity (MOE), and the internal bond (IB) strength. In general, the surface strand layers contributed to the MOR and MOE. The parallel MOR and MOE values were the largest for the single layered S panel (only Slayers: S1), but the perpendicular MOR and MOE was the smallest. Perpendicular MOR and MOE were the largest for seven layered composite that had two cross oriented strand layers (SPSPSPS: SP7). Specimens retained more than half of their MOE and MOR after two hours in boiling water and one hour soaking. IB was the largest for the panel having only P layers, however, differences in IB strength were not identified among the other multi-layered composite panels thus the effect of layer construction on IB strength was small. Thickness swelling (TS) and surface roughness were smaller for the composite having P layers on the surface than for those having S layers. The addition of strands did not enhance the mechanical properties (MOR, MOE, IB). TS values for the panels, with which the S/P ratio was over than 1:1, was the similar to the value for the single layered S panels.

• Journal of Chest Surgery
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• v.30 no.5
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• pp.512-516
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• 1997

We have experienced 66 cases of video assisted thoracic surgery(VATS) of spontaneous pneumothorax. The patients ranged in age from 1 Syears to 46years(mean age, 22.3years) and male patients were sixty three. The indications of video assisted thoracic surgery of spontaneous pneumothorax were recurrence, continuous air leakage, visible blabs on the chest X-ray & others. Infraoperative findings were as follows; blabs, pleural adhesion and pleural effusion. The operation was performed under general anesthesia wit double lumen endobronchial tube. Operative procedures included blebectomy and/or wedge resection of lung, vibramycin Pleurodesis with mechanical abrasion. In most cases, postoperative courses were uneventful and patients were discharged without significant complications. VATS provided the benefits of lesser postoperative pain, rapid recovery, short hospitalization, and smaller scar of wound. Conclusively VATS is a new interesting modality of surgical treatment of spontaneous pneumothorax and also can be extensively applicable in the diagnosis and treatment of other intrathoracic disease.

• Journal of Life Science
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• v.9 no.2
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• pp.127-135
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• 1999

Gentiana scabra Bunge var buergeri Max, can be widely used such as cut-flower, ornamental and medicinal plant among the native plants. Microscopic and Scanning electron microscopic observation plant were carried out to estimates the characteristics correlated with germinability and germination process, and the results were as follows. The seeds were germinated just after harvest, and it means that there is no or little dormancy of the seeds. Matured seeds showed higher germinability than those of immatured. As the storage period was longer, immatured seeds showed shorter longevity than those of matured. The average longevity was about 190 days. According to the observation results of morphological changes during the germination, seed coat was expanded with water absorption immediately after seeding, and radicals were observed 2 days after seeding. Root hairs were formed behind the growing tip of the root on 4 days after seeding and cotyledon were unfolded on 6 days after seeding. In the microscopic observation of leaf tissues, it could be easily distinguished between midrib, and leaf blade, and also observed upper epidermis, palisade parenchyma and spongy parenchyma consisted as a sing1e layer. Palisade parenchyma was consisted of a single layer of cell. Stomata were restricted lower surface, arranged as anamocytic type, and surrounded by guard cells. In the microscopic anatomy of stem were consisted of cortical layer, forming a single layer of epidermis and parenchyma, and vascular bundle which was consisted of continuous cylinder of vascular tissues.

• Journal of Yeungnam Medical Science
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• v.9 no.1
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• pp.137-148
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• 1992

The purpose of this study was to evaluate the influence of phenobarbital(PB) on hepatotoxic effect of carbon tetrachloride($CCl_4$) which induces centrilobular necrosis in liver. Rats were injected intraperitoneally $CCl_4$ dissolved in olive oil by a dose of 0.4mg/kg. For change related to PB pretreatment, rats were injected $CCl_4$ 0.4mg/kg after PB pretreatment. The liver samples were taken in 6, 12, 24, 48, 72, and 120 hours after $CCl_4$ and/or FB injection. Extracted liver tissue was examined with light and electron microscopes. The results were sumarized as follows : 1. Light microscopic findings : In $CCl_4$ group, centrilobular necrosis developed from 6 hours after injection, was the most severe in 48 hours, and recovered after 72 hours. In addition to necrosis, fatty change and pale cell change were accompanied. In PB-$CCl_4$ group, necrosis occurred from 6 hours after $CCl_4$ injection and continued to 72 hours, and the degree of necrosis was more severe than that of $CCl_4$ group and pale cell change was decreased. 2. Electron microscopic findings: In $CCl_4$ group, the early principal change was clumping and vesicular dilatation of endoplasmic reticulum. In PB-$CCl_4$ group, the degenerative change of endoplasmic reticulum was aggrevated and the mitochondria also revealed severe degenerative change. According to the results, it was revealed that $CCl_4$ hepatotoxicity primarily began with the damage of endoplasimic reticulum, then damage of other cell organelles and cell necrosis followed, and these cytotoxic effects were aggrevated by PB pretreatment.

• Korean Journal of Animal Reproduction
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• v.25 no.4
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• pp.371-379
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• 2001

The objective of this study was to establish an effective cryopreservation method of in vitro-produced bovine embryos. For the vitrification, in virtro-produced embryos at 8-cell, morula and blastocyst stages were exposed to freezing solution containing 5.5 M EG (EG 5.5) for 20 sec, loaded on each containers such as EM grid, OPS and Cryo-loop, and then immediately plunged into liquid nitrogen at -196$^{\circ}C$. Thawed embryos were serially diluted in 0.5, 0.25 and 0.125 M sucrose in m-HPBS, each for 1 min, and cultured in CRlaa medium supplemented with 10% FBS. Significant differences in the rates of re-expanded and hatched embryos were not observed among these embryo containers. The total cell number of expanded blastocyst cultured in vitro after vitrification was examined by Hoechst staining. There were no differences between non-vitrified (180.0 $\pm$ 5.4) and vitrified groups (178.0 $\pm$ 7.5). In addition, when the cellular injuries after vitrification were compared by double staining. There were no significant difference in the ratio of live and dead cells between non-vitrified group (176 : 4) and vitrified group (172 : 6). Therefore, these results suggest that bovine embryos can be cryopreserved easily, effectively and successfully by vitrification using various containers, such as EM grid, OPS or Cryo-loop in the presence of EG 5.5 freezing solution.

• Journal of the Korean Wood Science and Technology
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• v.14 no.1
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• pp.3-44
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• 1986

In order to obtain the basic physical and mechanical properties of steel wire reinforced particleboard, particleboards were formed with large particles through 2.11 mm (12 meshes) and retained on 1.27mm (20 meshes) sieves and small particles through 1.27mm (20 meshes) and retained on 0.42mm (60 meshes) sieves from the plywood mill wastes of meranti (Shorea spp.) in the form of pallmanchips, applying urea-formaldehyde resin as an adhesive on the particle surface in 10 percent on the oven dried weight of particles, and arranging steel wires of 1mm in diameter 5,10,15,20, and 25mm in longitudinal and transverse direction with crossing in the mid of the board depth in single layer boards, 10mm in longitudinal or transverse direction without crossing in two layers and 10mm in longitudinal and transverse directions with and without crossing in three steel wire layers boards. The stepwise 9-minutes-multi-pressing schedule in 5 minutes at 35 kgf/$cm^2$, 2.5 minutes at 25 kgf/$cm^2$. and 1.5 minutes at 15 kgf/$cm^2$ was applied for $300{\times}200{\times}13$mm board at the temperature of 160$^{\circ}C$ in a hot press. Specific gravity, thickness swelling, bending properties of modulus of rupture (MOR), modulus of elasticity(MOE), work to proportional limit, and work to ultimate load, internal bond (IB), and screw holding power(SHP) of the reinforced boards were analyzed on the wire openings and wire layers. The results obtained are summarized as follows; 1) In specific gravity, particleboards with large particles and small particles had higher value with more steel wire placements and more steel layers composition, 2) Particleboards with large particles in accordance with more steel wire liners composition gave very poor thickness swelling. 3) The mechanical properties of particleboards formed with large or small particles were reinforced with more steel wire layers. Therefore, bending strength was improved in modulus of rupture, modulus of elasticity, and work to ultimate load. Especiallv, particleboards with two or three steel wire layers showed the tension lamination effect when the steels in lower steel wire layer were oriented parallel to the board length. 4) The modulus of rupture, modulus of elasticity, and work to ultimate load in bending varied with opening area, distance of lengthwise wires multipled by distance of transverse wires. Particleboards formed with large particles resulted in higher value in modulus of rupture with 1.5-3 $cm^2$ opening area, 1-2cm distance between transverse wires, and 1.5-2.5cm distance between lengthwise wires. Particle boards formed with small particles showed higher value with 0.5-1.5$cm^2$ or 3.75-6.25 $cm^2$ opening area, 0.5 or 2.5cm distance between transverse wires. 5) In modulus of elasticity, particleboards formed with large particles with one steel wire layer suggested higher value with 5-3$cm^2$ opening area, 1-2.5cm distance between transverse wires and also 1-2.5 cm distance between lengthwise wires. Particleboards formed with small particles showed higher value with 0.75-1.25$cm^2$ or 3-6.25$cm^2$ opening area and 0.5 or 2.5cm distance between transverse wires. 6) Particleboards formed with large particles gaved higher value in work to ultimate load with 1-3$cm^2$ opening area. Particleboards formed with small particles showed increasing tendancy with decreasing opening area. 7) In internal bond and screw holding power, particleboards formed with large particles had increasing value in two and three steel wire layers compositions, but particleboards formed with small particles showed no difference. Particleboards formed with large particles containing one steel wire layer showed no difference in internal bond and screw holding power, and particleboards formed with small panicles containing one steel wire layer resulted in increasing value in internal bond and decreasing value in screw holding power in accordance with increase in opening area.