• 대한물리의학회지
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• 제8권3호
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• pp.379-385
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• 2013

PURPOSE: This study is research about deep trunk muscles (DTM) that is important and serve to control the movement of the trunk to provide stability during movement for human. In this study, trying to prove a change of DTM of aging in the ultrasound image. METHODS: We measured via an ultrasound image during rest and contraction of DTM in 42 young and 48 old people, and then we measured the change of thickness and symmetry. RESULTS: Symmetry showed a significant difference only external oblique (EO) in the young(p<.05). In the elderly, it was found that ratio of contraction was greater transverse abdominis than EO. CONCLUSION: I considered it could lead to improvement of activity of daily life by applying intervention for recovery of motor control of TrA for the elderly in clinical practice.

• 한국주조공학회지
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• 제1권2호
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• pp.10-18
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• 1981

In this paper tensile strength and fatigue propagation rate were investigated by aging treatment $(T_6)$ and thermomechanical treatment (TMT) of 7075-Al Alloy specimen. The results of teat showed that TMT improved tensile strength and fatigue crack propagation due to bomogenization of microstructure. In TMT, the results of comparison between T-H' AHA and T-AHA and $T-AH{\cdot}{\cdot}{\cdot}$and $T-HA{\cdot}{\cdot}{\cdot}$were showed that T-AHA and $T-AH{\cdot}{\cdot}{\cdot}$treatments, after solution treatment, which are aging treated before rolling have higher tensile strength. Our investigation on high temperature stability at the Specimen for $T_6$, T-AHA, $T-AH{\cdot}{\cdot}{\cdot}$treatments resulted in rapid reduction of tensile strength over $150^{\circ}C$, but the reduction of tensile strength for specimen of TMT was smoothed than $T_6$.

• 한국세라믹학회지
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• 제30권8호
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• pp.651-656
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• 1993

Granulated Y-TZP powders were coated by using Sol-Gel method and the coating effect of Al2O3 on the isothermal phase transformation in Al2O3 coated Y-TZP powders was investigated. During aging, tetragonal phase in Y-TZP powder were isothermally transformed to monoclinic, but the tetragonal phase in Al2O3 coated Y-TZP powders was continuously retained in spite of long aging. It can be considered that the improvement of thermal stability of tetragonal phase in Al2O3 coated Y-TZP powders may be due to the increase of constraint effect near tetragonal phase, and the suppression of surface transformation by obstructing the reaction between the surface of Y-TZP and H2O.

• Nuclear Engineering and Technology
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• 제48권1호
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• pp.175-181
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• 2016

This study investigates the dispersibility of carbon in carbon contained ammonium diuranate (C-ADU) gel particles and the characteristics of C-ADU gel liquid droplets produced by the vibrating nozzle and integrated aging-washing-drying equipment. It was noted that the excellent stability of carbon dispersion was only observed in the C-ADU gel particle that contained carbon black named CB 10. ADU gel liquid droplets containing carbon particles with the excellent sphericity of approximately 1,950 mm were then obtained using an 80-100-Hz vibrating nozzle system. Dried C-ADU gel particles obtained by the aging-washing-drying equipment were thermal decomposed until $500^{\circ}C$ at a rate of $1^{\circ}C/min$ in an air or in 4% $H_2$ gas atmosphere. The thermally decomposed C-ADU gel particles showed 24% weight loss and a more complicated profile than that of ADU gel particles.

• 한국축산식품학회지
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• 제43권6호
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• pp.961-974
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• 2023

This study investigated the effects of mustard seed extracts on physicochemical and storage characteristics of dry-aged pork loin ham during the aging period. In experiment 1, antioxidant activity was assessed for mustard seed extracted with varying ethanol concentrations and the results showed high antioxidant activity at 25%, 50%, and 75% ethanol concentrations. In experiment 2, pork loin was treated with mustard seed extracts obtained using different ethanol concentrations: not treated (control), 25% (MS25), 50% (MS50), and 75% (MS75). Physicochemical and storage characteristics of pork loin ham were measured in wk 0, 2, 4, and 6. The pH, a_w, CIE b^*, thiobarbituric acid reactive substances and volatile basic nitrogen values were lower in treated samples compared to the control (p<0.05). In conclusion, applying mustard seed extracts, particularly MS75, in the dry-aged pork loin ham production process could enhance storage stability and improve color attributes without having negative impacts on product quality.

• 한국축산식품학회지
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• 제26권1호
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• pp.85-91
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• 2006

한국 전통 장류를 이용한 양념 돈육의 저장 안정성에 관한 연구로 돼지고기의 등심을 채취하여 $5{\times}15{\times}5\;cm$ 크기로 자른 후 육을 동일한 비율의 양념액에 침지하여 $1{\pm}1^{\circ}C$에서 28일간 숙성하면서 양념육(간장소스 양념육, T1; 고추장소스 양념육, T2; 된장소스 양념육, T3)의 품질 특성을 조사하였다. 양념육의 표면 육색은 소스의 영향을 많이 받았으며 간장 소스로 양념한 돈육의 명도는 낮게, 고추장소스로 양념한 돈육의 적색도는 높게, 된장 소스로 양념한 돈육의 명도는 높게 나타났다. 심부 육색의 명도는 모든 처리구에서 숙성기간에 따라 감소하였으며, 간장 소스로 양념한 돈육에서는 낮게 나타났다. TBARS는 간장 소스로 양념한 돈육이 다른 처리구에 비해 낮게 나타났으며 전 숙성기간 동안 증가하였다. 총균수는 모든 처리구에서 숙성기간에 따라 증가하였으며 간장 소스로 양념한 처리구가 다른 처리구에 비해 전 숙성기간 동안 낮은 총균수를 나타내었다. 대장균 수는 숙성 초기 $2.7{\sim}3.27\;log_{10}CFU/g$으로 다소 높게 나타났으나 숙성기간의 증가에 따라 처리구들에서 감소하였으며, 고추장 소스로 양념한 처리구는 숙성 14일에 된장소스로 양념한 처리구는 숙성 28일에 대장균이 나타나지 않았다. 유산균 수는 간장 소스로 양념한 처리구에서 숙성기간 동안 유산균수의 증가가 나타나지 않았으며, 고추장 소스로 양념한 처리구와 된장 소스로 양념한 처리구에서는 숙성기간에 따라 증가하였다.

• 정보저장시스템학회논문집
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• 제8권2호
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• pp.50-55
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• 2012

Optical disks are widely used in libraries and archives as digital data media due to their long-term storage stability. Though archive-grade optical disks are already available on the market, there is a relative less focusing on the reliable recording conditions. Commercial BD-R media were recorded at various recording speeds with the maximum speed of 6X, and tested at the acceleration aging conditions. Through the evaluation of long-term storage features by the data stability test, lower recording speed of 2x resulted in better long-term storage stability. In addition, degradation aspects of unstable long-term storage feature at outer region of disk were discussed.

• 소성∙가공
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• 제14권1호
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• pp.71-77
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• 2005

Thermal stability and dry sliding wear behavior of ultra-fine grained 6061 Al alloy fabricated by an accumulative roll-bonding (ARB) process have been investigated. After 4 ARB cycles, an ultra-fine grained microstructure of the 6061 Al alloy composed of grains with average size of 500nm, and separated mostly by high-angle boundaries was obtained. Though hardness and tensile strength of the ARB processed Al alloy increased with ARB cycles up to 4 cycles, the processed alloy exhibited decreased ductility and little strain hardening. Thermal stability of the ARB-processed microstructure was studied by annealing of the severely deformed alloy at $423K{\sim}573K$. The refined microstructure of the alloy remained stable up to 473K, and the peak aging treatment of the alloy at 450K for 8 hrs increased the thermal stability of the alloy. Sliding-wear rates of the alloy increased with the number of ARB cycles in spite of the increased hardness with the cycles. Wear mechanisms of the ultra-fine grained alloy were investigated by examining worn surfaces, wear debris, and cross-sections by a scanning electron microscopy (SEM).

• 한국세라믹학회지
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• 제39권2호
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• pp.190-193
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• 2002

3Y-TZP에 희토류 산화물($CeO_2,\;Tb_2O_3$)을 0.5% 이하로 첨가시킨 지르코니아 단결정을 skull melting법으로 제조하여 오토클레이브 하에서 열수 상 안정성을 조사하였다. 극점도 측정결과, skull melting 법으로 제조한 $CeO_2$와 $Tb_2O_3$가 첨가된 시편들은 단결정이었으며 150∼250$^{\circ}C$에서 5시간 수증기 분위기 하에서 열처리한 후에도 정방정 상이 유지되는 우수한 열수 상 안정성이 관찰되었다.

• The Korean Journal of Ceramics
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• 제5권4호
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• pp.371-374
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• 1999

Y2O3 and Nb2O5 co-doped tetragonal zirconia polycrystals((Y, Nb)-TZP) containing 10 to 30 vol% $Al_2O_3$ were prepared and hydrothermal stability of the composites was evaluated after aging for 5 h at the temperature range of $150^{\circ}C$ $250^{\circ}C$ under 4 MPa $H_2O$ vapor pressure in an autoclave. The (Y, Nb)-TZP/Al2O3 composites showed excellent phase stability under the hydrothermal conditions, as compared with the 3Y-TZP/$Al_2O_3$ composites, due to the combined effects of the Y-Nb ordering in the $t-ZrO_2$ lattice, the reduction of oxygen vacancy concentration, and the $Al_2O_3$ addition. The strength and fracture toughness of the (Y, Nb)-TZP/$Al_2O_3$ composite, containing 20 vol% of 2.8 $Al_2O_3$ particles, were 700 MPa and 8.1 MP.$am^{1/2}$, respectively.