• 한국컴퓨터산업학회논문지
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• 제7권3호
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• pp.245-252
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• 2006

양극화로 인한 소외계층이 심화되고 고령화에 따른 사회복지가 대응하는 시간적 간격이 너무나 커지고 있다. 특히, 독거노인 환자의 증가로 인한 무관심이 사회문제로 비화되고 있는 실정이다. 더불어, 재택 골절환자의 비율도 급상승하고 있다. 국내적으로는 BT기술, 의료솔루션 기술은 현대기술의보조적 역할보다는 중추적인 역할을 제공하고 창조적 기술로 활용할 수가 있다. 특히, 초음파를 골절치료에 적용하면, 뼈가 잘 안 붙는 뼈의 골절치료 기간을 40% 가량 줄일 수 있다는 논문자료도 있다. 본 연구에서는 초음파 작동주파수가 1mHz, 1.3mHz, 1.5mHz의Piezo-ceramic crystal tranducer물질을 가지는 초음파 발생원 각각 4개를 한조로 하여 양단에 사용하였고, 임피이던스 및 Phase측정결과에 따라 외부직경이 각각4mm, 5.4mm, 두께0.5mm, 길이 70mm의 트랜스듀스를 사용하였다. 용량 50mW급으로 제작하였고, 초음파분포도를 조사하였다. <중략> 차후 시스템을 보완하면 골다공증 환자에도 적용이 될 것이고, 본 연구에서는 시제품을 직접 설계하고 비정형화 특성을 연구하고 기본적인 형태를 모델링 하여 접근해 보고자 노력해 보았다.

• 동의생리병리학회지
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• 제25권3호
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• pp.546-550
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• 2011

The aim of this study was to evaluate oriental medicine pattern identification in patients with stroke on the basis of plasma fibrinogen levels and platelet counts. 555 patients diagnosed with stroke between November 2006 and February 2010 were divided in several ways according to the plasma fibrinogen levels and platelet counts on admission. And comparative analysis of the distribution ratio of oriental medicine pattern identification was done between the groups. The mean value of the plasma fibrinogen levels of whole population was 449.18 mg/dL, and it was higher than normal range. The mean value of the platelet counts of whole population was 244.29 /mL, and it was lower but in normal range. Oriental medicine pattern identifications were not characteristic between groups divided according to the serum levels of fibrinogen and platelet counts. In this study, there was not significant correlation between Oriental medicine pattern identifications and the thrombotic factor like plasma fibrinogen levels and platelet counts. This study could be the steppingstone for the next study to develope the objective indicator for the Oriental medicine pattern identifications.

• 대한기계학회논문집B
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• 제26권1호
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• pp.150-158
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• 2002

Local heat/mass transfer and friction loss in a square duct roughened with various types of continuous and discrete rib turbulators are investigated. The combined effects of the gap flows of the discrete ribs and the secondary flows are examined for the purpose of the reduction of thermally weak regions and the promotion of the uniformity of heat/mass transfer distributions as well as the ;augmentation of average heat/mass transfer. The rib-to-rib pitch to the rib height ratio (p/e) of 8 and the rib angles of 90° and 60° are selected with e/D$\_$h/=0.08. The vortical structure of the secondary flows induced by the parallel angled arrays are quite distinct from that induced by the cross angled arrays. This distinction influences on heat/mass transfer and friction loss in all the tested cases. The gap flows of the discrete ribs reduce the strength of the secondary flows but promote local turbulence and flow mixing. Consequently, the angled discrete ribs with the small gaps provide a more uniform heat/mass transfer distribution sustaining high average heat/mass transfer.

• Journal of the Korean Wood Science and Technology
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• 제38권1호
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• pp.49-55
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• 2010

본 연구에서는 국내 수종 중 낙엽송(Larix Kaemferi Carr)을 대상으로 하여 톱밥의 특성별, 형태별로 나누어서 제조된 목재펠릿의 특성변화를 조사하였다. 제조된 펠릿의 함수율, 밀도, 회분, 흡습율, 발열량을 측정하여 비교하였다. 펠릿제품의 함수율은 6.4~7.31%로 나타나 목재펠릿의 품질기준 1급인 10% 이하를 만족시켰고, 대팻밥으로 제조한 펠릿의 밀도가 가장 높았고, 톱밥의 종류별 제조된 펠릿의 밀도는 큰 차이가 없었으며, 품질규격 1급을 만족시켰다. 회분은 0.2~0.424%로 품질규격 1급인 0.7% 미만의 범주에 속한 것으로 나타났으나, 수피만으로 제조된 펠릿의 회분량은 2.106%로 상당히 높은 값을 보여 1.5% (2급)을 초과하였다. 흡습율은 수피를 사용한 경우 추출물성분에 의해 수분 흡수 저해 효과가 있는 것으로 나타났으며, 제조된 각 펠릿의 발열량 측정결과 품질기준(1급) 4,300 kcal/kg을 넘어섰다.

• 분석과학
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• 제30권1호
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• pp.1-9
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• 2017

Starch is a mixture of amylose (AMY) and amylopectin (AMP) which are different in physical properties such as molar mass (M), rms radius ($R_g$) and hydrodynamic diameter ($d_H$). The rheological and functional properties of starch are influenced by various factors including the molecular size, molar mass distribution (MD) and the concentration ratio of AMY and AMP. It is also important to analyze proteinaceous material in starch as they affect the flavor and texture of food to which starch is added. In this study, asymmetrical flow field-flow fractionation (AF4) was employed for separation and quantitation of AMY and AMP in starches (Amaranth, potato, taros and quinoa). AF4 was coupled with a multi-angle light scattering (MALS) and a refractive index (RI) detector for determination of the absolute M, MD and molecular structure. It was found that AMP has the M and $R_g$ ranging $3.7{\times}10^7{\sim}6.5{\times}10^8g/mol$ and 84 ~ 250 nm, respectively. Also the existence of branch was confirmed in higher M. In addition, proteinaceous material in starch was analyzed by AF4 coupled with a fluorescence detector (FS) after fluorescence-labeling. AF4-FS with fluorescence-labelling showed a potential for investigation on existence of proteinaceous material and the interaction between proteinaceous material and polysaccharide in starch.

• 수산해양기술연구
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• 제41권4호
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• pp.296-305
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• 2005

Acoustic target strength (TS) of 12 commercially important fish species caught in the Korean waters had been investigated and their results were presented. Laboratory measurements of target strength on 12 dominant fish species were carried out at a frequencies of 75 kHz by single beam method under the controlled condition of the water tank with the 241 samples of dead and live fishes. The target strength pattern on individual fish of each species was measured as a function of tilt angle, ranging from $-45^{\circ}$ (head down aspect) to $45^{\circ}$ (head up aspect) in $0.2^{\circ}$ intervals, and the averaged target strength was estimated by assuming the tilt angle distribution as N ($-5.0^{\circ}$, $^15.0{\circ}$). The 75 to fish length relationship for each species was independently derived by a least - squares fitting procedure. Also, a linear regression analysis for all species was performed to reduce the data to a set of empirical equations showing the variation of target strength to fish length and fish species. An empirical model for fish target strength(TS, dB) averaged over the dorsal aspect of 158 fishes of 7 species and which spans the fish length(L, m) to wavelength(${\lambda}$, m) ratio between 6.2 and 21.3 was derived: TS: 27.03 Log(L)-7.7Log(${\kanbda}$)-17.21, ($r^2$=0.59).

• Food Science and Biotechnology
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• 제16권6호
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• pp.928-934
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• 2007

Physiochemical properties, such as yield and molecular weight distribution of polysaccharide fractions, of polysaccharides in the enzymatic hydrolysates of purslane were investigated and characterized. A higher amount of micro nutrients, such as potassium (9,413 mg/100 g), phosphorus acid (539 mg/100 g), leucine, alanine, lysine, valine, glycine, and isoleucine, was present in whole purslane. The yield of water soluble polysaccharides (WSP) was 0.29, 7.01, and 7.94% when extracted using room temperature water (RTW), hot-water (HW), and hot temperature/high pressure-water (HTPW), respectively, indicating that HW or HTPW extraction may be effective to obtain WSP from purslane. The average ratio of L-arabinose:D-galactose in the WSP was 37:49, 34:37, and 27:29, when extracted using RTW, HW, and HTPW, respectively. These results indicate that water was a suitable extraction solvent for preparation of the arabinogalactan component of whole purslane. A higher yield and total carbohydrate content was obtained by using Viscozyme L instead of Pectinex 5XL during extraction of the WSP, which indicates that enzymatic treatment of purslane may be an effective method to control the Mw of polysaccharides. Finally, it was confirmed that Viscozyme L is a suitable enzyme for the hydrolysis and separation of polysaccharides obtained from purslane.

• Food Science and Biotechnology
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• 제18권2호
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• pp.294-298
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• 2009

Distribution of isoflavones and fatty acids in soymilk fermented with 7 Lactobacilli (L-type), 7 Bifidobacteria (B-type), or 5 Streptococci (S-type) were monitored. Total isoflavones in fermented soymilk ranged from 5.24 to $8.59{\mu}mol/g$ dry basis while those in unfermented soymilk were $8.06{\mu}mol/g$ dry basis. Depending on the types of inoculated microorganisms, fermented soymilk showed different profiles in isoflavones, especially aglycones and $\beta$-glucosides. Four L-type fermented soymilk had significantly higher aglycone content (33.69-46.21%) and low $\beta$-glucosides compared to control (p<0.05). All B-type fermented soymilk showed significantly high aglycone levels (p<0.05). Out of 5 Streptococci, 4 strains produced over 82.2% aglycones. Lipid content ranged from 162 to 224 mg/g and linoleic acid was the highest, followed by oleic, linolenic, palmitic, and stearic acids. Average ratio of unsaturated to saturated fatty acids in control, L-, B-, and S-type fermented soymilks was 6.30, 6.09, 6.30, and 5.94, respectively. This study can help to develop a fermented soymilk containing high isoflavone aglycones and low fat content.

• 대한조선학회논문집
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• 제51권2호
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• pp.171-177
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• 2014

A two-dimensional particle image velocimetry (2D PIV) system in a towing tank is employed to measure a wake field of a very large crude oil carrier model with rotating propeller in self propulsion condition, to identify characteristics of wake of a propeller working behind a ship. Phase-averaged and time-averaged flow fields are measured for a horizontal plane. Scale ratio of the model ship is 1/100 and Froude number is 0.142. By phase-averaging technique, trajectories of tip vortex and hub vortex are identified and characteristic secondary vortex distribution is observed in the hub vortex region. Propeller wake on the starboard side is more accelerated than that on the port side, due to the difference of inflow of propeller blades. The hub vortex trajectory tends to face the port side. With the fluctuation part of the phase-averaged velocity field, turbulent kinetic energy (TKE) is also derived. In the center of tip vortex and hub vortex region, high TKE concentration is observed. In addition, a time-averaged vector field is also measured and compared with phase-averaged vector field.

• Structural Engineering and Mechanics
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• 제74권2호
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• pp.227-241
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• 2020

The bi-axial and shear buckling behavior of laminated hypar shells having rhombic planforms are studied for various boundary conditions using the present mathematical model. In the present mathematical model, the variation of transverse shear stresses is represented by a second-order function across the thickness and the cross curvature effect in hypar shells is also included via strain relations. The transverse shear stresses free condition at the shell top and bottom surfaces are also satisfied. In this mathematical model having a realistic second-order distribution of transverse shear strains across the thickness of the shell requires unknown parameters only at the reference plane. For generality in the present analysis, nine nodes curved isoparametric element is used. So far, there exists no solution for the bi-axial and shear buckling problem of laminated composite rhombic (skew) hypar shells. As no result is available for the present problem, the present model is compared with suitable published results (experimental, FEM, analytical and 3D elasticity) and then it is extended to analyze bi-axial and shear buckling of laminated composite rhombic hypar shells. A C⁰ finite element (FE) coding in FORTRAN is developed to generate many new results for different boundary conditions, skew angles, lamination schemes, etc. It is seen that the dimensionless buckling load of rhombic hypar increases with an increase in c/a ratio (curvature). Between symmetric and anti-symmetric laminations, the symmetric laminates have a relatively higher value of dimensionless buckling load. The dimensionless buckling load of the hypar shell increases with an increase in skew angle.