• 한국임상수의학회지
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• 제25권6호
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• pp.494-500
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• 2008

The aim of this study was to determine the effectiveness of hyaluronic acid-carboxymethylcellulose membrane (GUARDIX-$MB^{(R)}$) barriers on prevention against post-operative peritoneal adhesions. In this study, fourteen mongrel dogs were divided into two experimental groups: 0.1 % hyaluronic acid (0.1HA) group and hyaluronic acidcarboxymethylcellulose membrane (HA-CMC) group. In order to induce adhesions, the anti-mesenteric serosa of the ileum was exteriorized and then abraded in a standard manner by scraping with a scalpel blade to create homogenous petechial hemorrhagic surface over a $1\;{\times}\;1cm$ area. Solution of 0.1HA were simply coated over the abraded tissues, $1.5\;{\times}\;1.5cm$ HA-CMC membrane was placed over the abraded tissues, allowed to spread across the intra-abdominal organs before closure of the abdomen. On day 1 before and day 1, 4, 7, 14, and 21 after operation, venous blood specimens were collected for measurement of fibrinogen and total WBC. The adhesions were blindly assessed 3 weeks later by using a computerized tensiometer. The fibrinogen and total WBC values of two groups showed no statistical significances. The mean tensile strength (gram force, gf) of formed adhesions day 21 after surgery was $88.1\;{\pm}\;55.70gf$ in the 0.1 % HA group and $24.8\;{\pm}\;22.69gf$ in the HA-CMC group. The tensile strength values of adhesion separation HA-CMC membrane group was significantly lower than the 0.1HA group (p<0.05). Therefore, we suggest that HACMC membrane reduce peritoneal adhesions may be applicable to preventing post-operative intraperitoneal adhesions in dogs.

• 한국축산식품학회지
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• 제33권1호
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• pp.103-108
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• 2013

This study was carried out to observe the effect of superheated steam combined with oven heating on the physico-chemical and sensory properties of chicken meat. Specially, chicken breasts and thighs were heated for 40 min in various heating formulations such as oven heating, superheated steam heating or a combination of two kinds of heating. In the physical properties measurement, the shear force was increased as superheated steam heating time and chicken thighs were higher than chicken breasts in all treatments (p<0.05). The highest level of water holding capacity was solely superheated steam treated chicken for 40 min (p<0.05). The $L^*$ value was decreased but $a^*$ value or $b^*$ value were increased after cooking. Chicken breast exhibited a higher colour value than chicken thigh. Superheated heating was effective to reduce heating loss as 22.64% (p<0.05). However, pH was not different depending on the heating formulation or part of the chicken meat (p>0.05). In the sensory test, the combination of 10 min oven heating and 30 min superheated steam heating was effective to create a good flavour of chicken meat. In this study, an optimum formulation was developed which was a combination of 10 min oven heating and 30 min superheated steam heating. It was more effective to improve the quality of chicken meat than the single heat treatment of chicken meat.

• Steel and Composite Structures
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• 제25권6호
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• pp.639-648
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• 2017

Fracture energy values KV have been measured on cast steel, used in the container manufacture, by instrumented Charpy impact testing. This material has a large ductility on the upper transition region at $+20^{\circ}C$ and a ductile tearing with an expended plasticity before a brittle fracture on the lower transition region at $-20^{\circ}C$. To assess the fracture toughness of this material we use, the $K_{IC}$-KV correlations to measure the critical stress intensity factor $K_{IC}$ on the lower transition region and the dynamic force - displacement curves to measure the critical fracture toughness $J{\rho}_C$, the essential work of fracture ${\Gamma}_e$ on the upper transition region. It is found, using the $K_{IC}$-KV correlations, that the critical stress intensity factor $K_{IC}$ remains significant, on the lower transition region, which indicating that our testing material preserves his ductility at low temperature and it is apt to be used as a container's material. It is, also, found that the $J_{\rho}-{\rho}$ energetic criterion, used on the upper transition region, gives a good evaluation of the fracture toughness closest to those found in the literature. Finally, we show, by using the ${\Gamma}_e-K_{IC}$ relation, on the lower transition region, that the essential work of fracture is not suitable for the toughness measurement because the strong scatter of the experimental data. To complete this study by a numerical approach we used the ANSYS code to determine the critical fracture toughness $J_{ANSYS}$ on the upper transition region.

• 한국약용작물학회지
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• 제17권3호
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• pp.204-209
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• 2009

This study was conducted to assess water movement in paddy-upland rotation soil scheduled for ginseng cultivation through the measurement of infiltration and permeability of soil water. Soil sample was divided with four soil layers. The first soil layer (to 30cm from top soil) was loamy sand, the second and the third soil layers (30$\sim$70 ㎝) were sand, and the fourth (< 120 ㎝) was sandy loam. The soil below 130 ㎝ of fourth soil layer was submerged under water. The shear strength, which represents the resisting power of soil against external force, was 3.1 kPa in the first soil layer. This corresponded to 1/8 of those of another soil layer and this value could result in soil erosion by small amount of rainfall. The rates of infiltration and permeability depending on soil layers were 39.86 cm $hr^{-1}$ in top soil, 2.34 cm $hr^{-1}$ in 30$\sim$70 ㎝ soil layer, 5.23 cm $hr^{-1}$ and 0.18 cm $hr^{-1}$ in 70$\sim$120 ㎝ soil layer, with drain tile, and without drain tile, respectively. We consider that ground water pooled in paddy soil and artificial formation of soil layer could interrupt water canal within soil and affect negatively on water movement. Therefore, we suggest that to drain at 5 m intervals be preferable when it makes soil dressing or soil accumulation to cultivate ginseng in paddy-upland rotation soil to reduce failure risk of ginseng cultivation.

• Electronic Materials Letters
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• 제14권6호
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• pp.669-677
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• 2018

In this work, the high ${\kappa}$ $Zr_xAl_{1-x}O_y$ films with a different Zr concentration have been deposited by atomic layer deposition, and the effect of Zr concentrations on the structure, chemical composition, surface morphology and dielectric properties of $Zr_xAl_{1-x}O_y$ films is analyzed by Atomic force microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and capacitance-frequency measurement. The effect of Zr concentrations of $Zr_xAl_{1-x}O_y$ gate insulator on the electrical property and stability under negative bias illumination stress (NBIS) or temperature stress (TS) of ZnSnO (ZTO) TFTs is firstly investigated. Under NBIS and TS, the much better stability of ZTO TFTs with $Zr_xAl_{1-x}O_y$ film as a gate insulator is due to the suppression of oxygen vacancy in ZTO channel layer and the decreased trap states originating from the Zr atom permeation at the $ZTO/Zr_xAl_{1-x}O_y$ interface. It provides a new strategy to fabricate the low consumption and high stability ZTO TFTs for application.

• 대한조선학회논문집
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• 제31권3호
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• pp.65-79
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• 1994

본 연구에서는 선미벌브의 채택이 유체력 특성 및 조종성능에 미치는 영향에 관해서 실험적으로 고찰하였다. 연구방법으로서는 일반선미 형상과 선미벌브 형상을 가지는 각각의 모형선을 공시선으로, 회류수조에서 조종성 관련 구속모형시험을 실시하여 양 선형의 차이에 기인하는 유체력 특성과 조종성능을 비교, 검토하였다. 연구 결과, 선미벌브를 채택함으로써 침로안정성은 나빠지지만 선회력이 향상됨을 확인하였고, 이러한 조종성능의 특성과 유체력 특성과의 상관관계를 규명하였다.

• 공업화학
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• 제32권6호
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• pp.700-705
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• 2021

본 연구에서는 하이드로늄 이온 농도를 모니터링하기 위한 티타늄(Ti) 와이어를 기반으로 하는 휴대용 일회용 pH 센서를 성공적으로 개발하였다. 센싱 전극은 Ti 와이어에 이리듐 산화물을 전기화학적으로 증착하여 제조하였고, 기준 전극으로 Ti 와이어에 Ag/AgCl 잉크를 코팅하였다. pH 센서에 두 개의 전극을 결합한 후 pH 센서를 다양한 pH 용액에 담그면 개방 회로 전위 신호를 수집할 수 있다. 상기 제조된 pH 센서는 감도, 응답 시간, 반복성, 선택도 및 안정성 측면에서 우수한 전기화학적 감지 성능을 보여 주었다. 현장 검사 응용을 시연하기 위해서 pH 센서를 모바일 애플리케이션과 통신할 수 있는 무선 전자 모듈과 통합하였다. 이 휴대용 pH 센서는 실제 샘플의 pH 변화를 정확하게 측정했으며 결과는 상용 pH 측정기의 데이터와 일치하였다.

• Tribology and Lubricants
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• 제35권3호
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• pp.183-189
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• 2019

The driver seat of an automobile is in direct contact with the driver and provides the driver with a safe and comfortable ride. The seat consists of a frame, a rail, and many recliners. In recent years, strength and operating force measurement testing of the recliner have become vital for designing car seats. However, performance evaluation requires expensive testing equipment, numerous seat products, and considerable time. Therefore, the trend is to reduce experimentation through interpretation. This study examines the lubrication of solid lubricant for automotive seat recliners and confirms the friction and wear performance. In this study, the lubrication behavior of solid lubricants for car seat recliners is investigated to ascertain the friction and wear performance and to provide accurate values for the strength analysis. The friction material consists of a pin and a plate made from steel, which is widely used in recliners. The friction and wear under lubrication conditions are measured by a reciprocating friction wear tester. The friction coefficient is obtained according to the load and speed. Based on the obtained results, it is possible to achieve a reduction in the error of the test value and the analysis by providing the friction coefficient and wear of the lubricant. The results can be applied to the analysis of automobile seat design.

• Tribology and Lubricants
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• 제35권2호
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• pp.99-105
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• 2019

This study presents an experimental investigation of the wear and oxidation of the bristles of a brush seal in a super-heated steam environment. We construct a model reflecting normal force and radial interference to predict the amount of wear. To monitor the volume loss of the bristle induced by the swirl phenomenon of the rotor, we measure the clearance between the rotor and the brush seal by using a non-contact 3-D device. We calculate the area by using the area-wise measurement method. Considering the obvious brush seal wear variables, we use two disks with different roughness($Ra=0.1{\mu}m$ and $100{\mu}m$) to determine the effect of roughness on wear. Considering an actual steam turbine, we utilize a steam generator and super-heater to generate a working fluid (0.95MPa, 523.15K) that has high kinetic energy. We observe the abrasion of the bristles in the hot steam environment through a scanning electron microscope image. This study also conducted energy dispersive X-ray (EDX) analysis for a qualitative evaluation of local chemistry. The results indicate that the wear and elimination of bristles occur on the disk with high roughness, and the weight increases due to oxidation. Furthermore these results, reveal that the bristle oxidation is accelerated more under super-heated steam conditions than under conditions without steam.

• 한국인터넷방송통신학회논문지
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• 제19권1호
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• pp.279-287
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• 2019

본 논문에서는 신체의 움직임 정보와 족압 분포의 변화를 측정하여 신체 균형 능력을 분석하고자 하였다. 그래서 관성측정장치와 FSR 센서를 사용하여 관절가동범위와 신체압력중심을 측정하고 분석할 수 있는 프로그램을 개발하였고, 이에 대한 결과를 바탕으로 균형 능력 개선에 도움을 줄 수 있는 콘텐츠를 제작하였다. 이 프로그램에서 측정된 관절가동범위와 신체압력중심의 정량적인 값을 실시간으로 시각화하여 사용자가 결과를 쉽게 알 수 있도록 하였다. 또한 콘텐츠는 측정된 균형정보를 바탕으로 난이도가 조절되며 균형능력을 개선하고자 하는 방향에 맞춰 수행할 수 있도록 제작되었다. 이것은 사용자의 동작에 따라 움직이는 물체를 보면서 진행하는 시각 되먹임 방법을 이용하여 집중력과 참여의지를 높여 더욱 효과적인 균형 훈련 결과를 기대할 수 있다.