• 대한간호학회지
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• 제24권4호
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• pp.517-528
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• 1994

The purpose of this study was to compare the circumference, skinfold thickness and strength of the normal and casted lower limb prior to casting and following removal of the cast. The subjects for the study were nine orthopedic patients who had had long and short leg casts due to a tibial, fibula, or calcaneus fracture, or to a lateral collateral ligament rupture. Circumference, skinfold thickness, and strength of the normal and casted lower limb following removal of the cast were compared with those prior to the application of the cast. Measurements were made before cast application and after removal of the cast. Skinfold thickness was measured by fat caliper, circumference was measured by tape and strength was determined by measuring the length of time the leg was held elevated at 45$^{\circ}$. The results can be summarized as follows 1. There was no change in the normal limb in the circumference of the midthigh and midcalf after casting as compared to before cast application. 2. In the casted limb the circumference of the midthigh decreased by 3.23% and that of the midcalf decreased significantly by 7.49% during the period of casting. 3. In the normal limb skinfold thickness of the quadriceps decreased and that of gastrocnemius increased by 20.63% during the period of cast application. 4. In the casted limb skinfold thickness of the quadriceps decreased significantly by 12.37% and that of gastrocnemius decreased by 10% during the period of cast application. 5. Strength of the normal lower extremity decreased significantly by 48.37% and that of casted lower extremity decreased remarkably by 73.07% during the period of cast application. 6. Circumference of the midthigh and the midcalf decreased significantly by 7.6% and 9.4% respectively on the casted side as compared to the normal side. Skinfold thickness of the quadriceps and the gastrocnemius on the casted side decreased by 6.12% and 18.55% respectively as compared to the normal side and strength in the lower extremity on the casted side decreased significantly by 44.32% as compared to the nor-mal side. From these results, it may be concluded that muscle atrophy occurs in the casted lower limb and muscle strength of the normal lower limb are also reduced during the period of application of a leg cast.

• 한국세라믹학회지
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• 제32권2호
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• pp.189-196
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• 1995

Materials retaining electrolyte of a phosphoric acid fuel cell (PAFC) have been prepared with SiC powder to SiC whisker mixing ratios of 1:1, 1:2, 1:3, 1:4, 0:1 by a tape casting method. When 3wt% dispersant (sorbitan monooleate) is added to a matrix, the porosity of the matrix decreases a little while the bubble pressure and area of the matrix increase remarkably in comparison with no dispersant content. Effect of the electrolyte resistance and the polarization resistance on perfomance of a PAFC has been investigated using A.C. impedance spectroscopy. With the increase of whisker content, the electrolyte resistance decreases due to the increase of porosity and acid absorbancy, and the polarization resistance increases due to the increase of surface roughness. The polarization resistance affects current density predominantly at the higher potential than 0.7V becuase the polarization resistance is considrably larger than the electrolyte resistance. Both the electrolyte resistance and the polarization resistance affect current density near 0.7V of the fuel cell operating potential because they have similar values. The electrolyte resistance affects current density predominantly at the lower potential than the fuel cell operating potential because the electrolyte resistance is larger than the polarization resistance.

• 한국산학기술학회논문지
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• 제6권6호
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• pp.497-501
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• 2005

Dry film 공정에 의해 PDP(Plasma Display Panel)용 무연 투명유전체를 제조하였다. 여러 슬러리 조성으로부터 고밀도 green sheet를 제조하는데 최적의 조성을 선정하였다. 한편, 슬러리는 양질의 green sheet를 제작하는데 적합한 shear thinning 특성을 나타냈다. 제조한 투명유전체의 열팽창계수는 유리기판인 PD-200과 유사한 $97{\times}10^{-7}/^{\circ}C$로 측정되었다. PD-200에 접합된 투명유전체의 단면 주사현미경 관찰로부터 두 층은 갭이 없이 매우 견실히 접합되어 있음을 확인할 수 있었다.

• 신재생에너지
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• 제4권1호
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• pp.11-18
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• 2008

In-situ lithiated NiO has been manufactured as a conventional cathode material of molten carbonate fuel cell (MCFC), however this material has a weakness for commercialization of MCFC because NiO is spontaneously dissolved into the electrolyte under MCFC operating conditions, resulting in short circuit between cathode and anode. In this research, therefore, $Co(OH)_2$-coated Ni powder was prepared by precipitation method with controlling pH at low temperature and atmospheric pressure. Modified cathode was fabricated by a conventional tape casting method and sintered at 700$^{\circ}C$ in a $H_2/N_2$ atmosphere, Based on characterization result, Pore size distribution and porosity was suitable for the cathode of MCFC. According to the result of dissolution, Ni solubility of modified cathode was 33% lower than that of conventional cathode. In addition, modified electrode showed a good performance from the single cell operation.

• 신재생에너지
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• 제3권1호
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• pp.54-59
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• 2007

A sintering aid, $B_{2}O_{3}$ have been included into a $LiAlO_{2}$ electrolyte support by a tape casting method in order to reinforce mechanical strength of the support for molten carbonate fuel cells [MCFCs). Starting idea originates from the low melting point of $B_{2}O_{3}$ ($450^{\circ}C$), which can provide the low temperature consolidation of ceramic materials. The mechanical properties and the microstructure changes of the $B_{2}O_{3}$-included electrolyte support were examined by scanning electron microscope, mercury porosimetry, X-ray powder diffraction [XRD], high temperature differential scanning calorimeter and three-point bending strength measurement. The mechanical strength was clearly improved by addition of $B_{2}O_{3}$. The increase of mechanical strength results from the neck growth of a new $LiAlO_{2}$ phase between $LiAlO_{2}$ particles by the liquid phase sintering. Average pore size and porosity of the electrolyte support reinforced by addition of the sintering aid, $B_{2}O_{3}$, was $0.24{\mu}m$ and 59%, respectively which were suitable microstructure of a matrix for an application of MCFCs.

• 한국분말재료학회지
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• 제15권4호
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• pp.292-296
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• 2008

The electromagnetic (EM) wave absorption properties of the $Fe_{73}Si_{16}B_7Nb_3Cu_1$ nanocrystalline powder mixed with 5 to 20 vol% of Ni-Zn ferrites has been investigated in a frequency range from 100MHz to 10GHz. Amorphous ribbons prepared by a planar flow casting process were pulverized and milled after annealing at 425 for 1 hour. The powder was mixed with a ferrite powder at various volume ratios to tape-cast into a 1.0mm thick sheet. Results showed that the EM wave absorption sheet with Ni-Zn ferrite powder reduced complex permittivity due to low dielectric constant of ferrite compared with nanocrystalline powder, while that with 5 vol% of ferrite showed relatively higher imaginary part of permeability. The sheet mixed with 5 vol% ferrite powder showed the best electromagnetic wave absorption properties at high frequency ranges, which resulted from the increased imaginary part of permeability due to reduced eddy current.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.149-152
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• 2001

A great deal of attention has been focused on the application of miniaturized piezoelectric transformers to the low power source for the microsystem. The dielectric and piezoelectric properties of Pb(Mn,W,Sb,Nb)O$_3$-Pb(Zr,Ti)O$_3$ ceramics have been investigated on different calcination(750$^{\circ}C$∼950$^{\circ}C$) and sintering(1100$^{\circ}C$∼1300$^{\circ}C$) temperatures. The perovskitic phase was formed by the solid phase reaction of the oxides. Anisotropic (k$\sub$t/k$\sub$p/) properties of electromechanical coupling coefficient and piezoelectric coefficient have been proven to be depending on processing temperatures. The value of electromechanical coupling factor of K$\sub$p/>0.51 and a mechanical quality factor of Q$\sub$m/>2000 were obtained. The piezoelectric transformer was prepared using this ceramics with the composition of Pb(Mn,W,Sb,Nb)O$_3$-Pb(Zr,Ti)O$_3$ We studied the influence of different processing temperature on the microstructure and piezoelectric properties of complex PZT-based ceramics. and the characteristic of piezoelectric transformer.

• 한방재활의학과학회지
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• 제27권4호
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• pp.1-9
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• 2017

Objectives Oxidative stress, in which antioxidant proteins and scavenger protection are overwhelmed by reactive oxygen species (ROS) production, is recognized as one of central causes of disuse muscle atrophy. In this study, the hypothesis that oral treatment with Dangguibohyul-tang (Dangguibuxuetang) could attenuate immobilization-induced skeletal muscle atrophy was tested. Methods The hindlimb immobilization was performed with casting tape to keep the left ankle joint in a fully extended position. The Rats in Dangguibohyul-tang treated group (DGBHT) (n=10) were orally administrated Dangguibohyul-tang water extract, and rats of Control group (n=10) were given with saline only. After 2 weeks of immobilization, the morphology of right and left gastrocnemius muscles in both DGBHT and Control groups were assessed by hematoxylin and eosin staining. Results Dangguibohyul-tang water extract represented the significant protective effects against the reductions of the left gastrocnemius muscles weight and average cross section area to compared with Control group. Moreover, the treatment with Dangguibohyul-tang extract significantly enhanced the Cu/Zn-SOD activities in gastrocnemius muscle compared with Control group. Conclusions Thses results suggest that Dangguibohyul-tang has protective effects against immobilization-induced muscle atrophy by increasing the Cu/Zn-SOD activities in gastrocnemius muscle.

• 한국전기전자재료학회논문지
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• 제15권10호
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• pp.896-901
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• 2002

The polarization and strain behavior of multilayer ceramic actuators fabricated by tape casting using a PNN-PZT ceramics were investigated in association with electrode size and internal layer number. Spontaneous polarization and strain decreased with increasing electrode size. In addition, the increase of internal layer number brought reduced spontaneous polarization and increased the field-induced strain. Because the actuators structure is designed to stack ceramic layer and electrode layer alternatively, the ceramic-electrode interfaces may act as a resistance to motion of domain wall. To analyze the effect of ceramic-electrode interface, the diffraction intensity ratio of (002) to (200) planes was calculated from X-ray diffraction patterns of samples subjected to a voltage of 200 V. The diffraction intensity ratio of (002) to (200) planes was decreased with increasing electrode size and internal layer number. The diffraction intensity ratio and straining behavior analyses indicate that the Polarization and strain were affected by the amount of 90°domain decreasing with increasing electrode size and internal layer number. Consequently, the change of polarization and displacement with respect to electrode size and layer number is likely to be caused by readiness of the domain wall movement around the interface.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.334-334
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• 2010

In order to fabricate the multilayer piezoelectric transformer by tape casting method, we investigated the effect of $TiO_2$ and PZT powder additions on the Ag/Pd electrode. Meanwhile, effects of $TiO_2$ and PZT powder additives on the microstructure and electrical properties of Ag/Pd electrode were investigated in detail. In addition, the multilayer piezoelectric transformers were fabricated and the characteristics with various load resistance were measured at resonance frequency. The voltage step-up ratio was continuously change with increasing input voltage and load resistance, and then output voltage and powers were increased with increasing input voltage at matching impedance. The temperature rise of multilayer piezoelectric transformers were increased with increasing input voltage and load resistance. Meanwhile, multilayer piezoelectric transformers sintered at $1100^{\circ}C$ show the favorable characteristics with a power of 15 W at $100\;{\Omega}$.