• 한국수산과학회지
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• 제17권5호
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• pp.353-360
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• 1984

유전가열을 이용한 내부가열로서 어육연제품을 조리${\codt}$살균함과 동시에 내부수분을 확산${\codt}$이탈시켜 제품의 수분활성을 조절하여 상온보장이 가능한 보장성 어묵을 가공하는 방법과 제품개발을 위한 원료첨가물의 배합 및 가공조건을 검토한 실험결과를 요약하면 다음과 같다. (1) 고등어 연육의 첨가물 배합조건은 고기풀 100에 대하여 전분(옥수수 전분) $10\%$, 소금 $1.5%$, MSG $0.6\%$, sorbitol $3.0\%$, 설탕 $2.0\%$일 때가 가장 적당하였다. (2) 연제품의 형상과 크기는 두께 0.8cm, 직경 8cm의 원반형이 균일한 가열과 팽화 및 표면경화를 막는데 가장 적당하였고, 이것은 연육을 8cm 직경의 원주형으로 충전하여 이것을 열탕중에서 $2{\sim}3$분간 가열처리하여 gel시킨 후 0.8cm 두께로 절단하여 만들수 있으므로 조작이 매우 편리하였다. 동시에 열탕처리는 유전 가열시간을 단축시키는 효과도 있었다. (3) 유전가열은 $5{\sim}6$분간을 2분, $1{\codt}5$분, $1{\codt}5$분 및 1분씩으로 간헐적으로 행하는 것이 제품의 성상과 수분활성 조절 및 살균효과가 좋았다. 1단계 가열에 의하여 확산${\codt}$이탈된 수분은 $60^{\circ}C$, 3m/sec의 열풍으로 2분간 건조하고 계속적으로 600 W 전열기로 $5{\sim}6$분간 가열 표면배소와 함께 최종적으로 수분활성을 조절할 수 있었다. (4) (3)과 같은 조건으로 가공한 연제품은 수분활성 0.84{\sim}0.86, 생균수 $3{\times}10^2/g$이하, TI함량 27.6mg/g였고 texture 시험성적은 hardness 42, cohesiveness 0.53, toughness 4.6, elasticity 0.8, folding test AA였다. (5) 연제품의 일반성분 조성은 수분 $40.1\%$, 단백질 $20.8\%$, 지방 $17.4\%$, 탄수화물 $16.2\%$ 및 회분$5.5\%$였다.

• 한국세라믹학회지
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• 제33권11호
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• pp.1267-1275
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• 1996

Green sheet was prepared by tape casting in the composition of (1-x)Pb(Mg1/3Nb2/3)O3-PbTiO3 system using Pb(Mg1/3Nb2/3)O3 and PbTiO3 synthesized with PbO, Nb2O5 MgO and TiO2 The densest green sheet was obtained in the weight ratio 70:30 of powder to binder. Green sheet wasmultilayered in metal mould and formed into lamination at 7$0^{\circ}C$, 300kg/cm2 The lamination was sintered at 110$0^{\circ}C$ 2hr, Dielectric constant and Curie temperature of disc type sintered body was highered with increasing the amount of PbTiO3 and was in the range of 19000-21000, -7~45$^{\circ}C$ respectively. Green and sintered relative density of lamination was 61% and 95% respectively.

• 한국세라믹학회지
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• 제20권3호
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• pp.227-235
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• 1983

The dielectric and piezoelectic properties in which $(Zr_{0.52} Ti_{0.48})^{+4}$ ions of $Pb(Zr_{0.52} Ti_{0.48})O_3$ are partially substituted for $W^{+6}$ ions were studied. $ZrTiO_4$ was made by coprecipitation. The specimens of disc shape were sintered respectively at 1180$^{\circ}$to 130$0^{\circ}C$ at an intervals of 2$0^{\circ}C$ for 1 hour. The optimum sintering temperature were found to be between 126$0^{\circ}C$ and 128$0^{\circ}C$. PZT solid solutions sintered had the tetragonal structure with c/a=1.025$\pm$0.005 and theoretical densities incre-ased from 8.02 to 8.17g/cm3 with increasing the amount of the partial substitution of $(Zr_{0.52} Ti_{0.48})^{+4}$ ion for $W^{+6}$ ion The grain size and curie temperature decreased with increasing the amount of $WO_3$ while the dielectric constant increased. When $(Zr_{0.52} Ti_{0.48})^{+4}$ ion was substituted for 1 mole% of $W{+6 ]$ion the planar coupling coefficient$(K_P)$ was as high as 0.58 But as the amount of $WO_3$ increased the mechanical quality factor(Qm) decreased considerably.

• E2M - 전기 전자와 첨단 소재
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• 제8권5호
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• pp.558-563
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• 1995

Dynamic characteristics of TbFeCo magneto-optical recording media at 680nm wavelength region were studied by means of computer simulation of disc structure and optimization of process variables during sputter deposition. With the slightly reduced Kerr rotation angle due to the reduced wavelength of optical laser source, the improved recording density in TbFeCo magneto optical media showing the CNR greater than 50dB could be achieved by only adjusting the thickness of dielectric and the recording layers when the wavelength of light source is changed from 780nm to 680nm. In addition, the recording power margin of 5mW and the 2mW minimum recording power was realized, It was shown from the present study that the increase in laser power density demonstrated feasibility of low cost and low power laser diode with the reduced optimum recording power.

• 한국전기전자재료학회논문지
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• 제14권1호
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• pp.12-19
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• 2001

In this study, the physical properties of the piezoelectric sounder with metal-piezoelectric ceramics were analyzed. The dielectric and piezoeletric properties of 0.5wt% MnO$_2$ and NiO doped 0.1Pb(Mg$\_$1/3/Nb$\_$2/3/)O$_3$-0.45PbTiO$_3$-0.45PbZrO$_3$ ceramics were investigated aiming at acoustic transducer applications. The acoustic characteristics of a thin circular disc-type with metal-piezoceramics have been investigated. Also, the acoustic characteristics for the geometrical form of case were investigated. The piezoelectric sounder with 200kHz resonant frequency and 20kHz bandwidth was designed by considering the sharp directivity and the sound pressure.

• 한국음향학회:학술대회논문집
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• 한국음향학회 2000년도 하계학술발표대회 논문집 제19권 1호
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• pp.275-278
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• 2000

In this study, the acoustic transducer of a thin circular disc-type with PZT/Metal was designed. The dielectric and piezoelectric properties of $0.5wt\%$ $MnO_2$ and NiO doped 0.1Pb($Mg_{1/3}$$Nb_{2/3}$)$O_3$-$0.45PbTiO_3$-$0.45PbZrO_3$ ceramics were investigated aiming at acoustic transducer applications. The vibration characteristics for the laminated circular plate was analyzed for the various thickness and diameter of the piezoceramic layer and metal layer. The acoustic characteristics which is radiated from the acoustic transducer within the finite space was simulated using the finite element method. It has been observed that the characteristics of the sound pressure ard impedance response calculated for the various models of the size and geometry of acoustic transducer.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 C
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• pp.1081-1084
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• 1995

Internal voids located within an insulation will arise partial discharge that causes local breakdown and even the entire insulation breakdown. For HV apparatuses, it is usual case that several voids are formed within non-uniform electric field condition rather than single void within uniform field, which can be solved analitically. The purpose of this work is to study partial discharge and breakdown characteristics of an insulation according to the distribution pattern of two disc-type voids that are located within non-uniform field. The results from numerical field analysis and experiments show that the electric field within the voids decreases as they are arranged more serially, which accordingly results in the increase of partial discharge inception field(PDIF) much higher than that of single void model. With parallel arranged voids, PDIF is almost the same as that of single void model. On the other hand, AC breakdown strength decreases as voids are arranged more serially, which is a natural result considering the reduction of effective insulation thickness. For parallel voids, this effect cannot he noticed where as they show different pattern compared with single void and serial void models in $\Phi$-Q-N analysis. Considering these results may leads us to the conclusion that, in the evaluation of insulating products through PD test, it is not sufficient to determine only PDIV or existence of PD at predetermined voltage level. We could evaluate more accurately by considering all the available data such as PDIV, PD magnitude, PD occurring phase, number of PD pulses, and etc.