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Low-Temperature Electron Transport Properties of La2/3+xTiO3-δ (x = 0, 0.13) (저온에서 La2/3+xTiO3-δ (x = 0, 0.13)세라믹스의 전자전도특성)

  • Jung, Woo-Hwan
    • Korean Journal of Materials Research
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    • v.24 no.11
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    • pp.604-609
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    • 2014
  • The thermoelectric power and dc conductivity of $La_{2/3+x}TiO_{3-{\delta}}$ (x = 0, 0.13) were investigated. The thermoelectric power was negative between 80K and 300K. The measured thermoelectric power of x = 0.13 increased linearly with increased temperatures and was represented by $S_0+BT$. The x = 0 sample exhibited insulating behavior, while the x = 0.13 sample showed metallic behavior. The electric resistivity of x = 0.13 had a linear temperature dependence at high temperatures and a T3/2 dependence below about 100K. On the other hand, the electric resistivity of x = 0 has a linear relation between $ln{\rho}/T$ and 1/T in the range of 200 to 300K, and the activation energy for small polaron hopping was 0.23 eV. The temperature dependence of thermoelectric power and the resistivity of x = 0 suggests that the charge carriers responsible for conduction are strongly localized. This temperature dependence indicates that the charge carrier (x = 0) is an adiabatic small polaron. These experimental results are interpreted in terms of spin (x = 0.13) and small polaron (x = 0) hopping of almost localized Ti 3d electrons.

A Study on the Calculation Formulae for the Required Air and Combustion Gas of the Domestic Anthracites (국산무연탄의 소유공기량과 발생연소가스량의 산식에 관한 연구)

  • 이우환
    • Journal of Advanced Marine Engineering and Technology
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    • v.5 no.1
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    • pp.28-33
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    • 1981
  • The characteristics of typical 35 kinds of domestic anthracites among 155 kinds are studied to find the calculation formula for the required quantity of air and the combustion gas quantity. 1) The author's calculation formulae are as follows: ${A_0}={\frac{1, 000}{1, 064}}{H_1}+0.086(Nm^3/kg)$ ${G_0}={\frac{1, 000}{1, 110}}{H_1}+0.234(Nm^3/kg)$(1) Theoretically required quantity of air (2) Theoretical quantity of combustion gas 2) Theoretical quantity of air in combustion of domestic anthracite is always estimated more with Rosin's formula than author's one in the typical domestic anthracites which have the lower calorific value between 3, 000-8, 000 Kcal/kg and the difference of the calculated quantity of air becomes small, as the calorific value increases. 3) Theoretical quantity of combustion gas is estimated more by author's formula than by Rosin's one with the domestic anthracites which have more calorific value than 6, 700 Kcal/kg and is estimated less in the under range of the above calorific value. 4) Theoretical quantity of required air and quantity of combustion gas of domestic anthracite show ${\pm}$4% difference by Rosin's formulae in comparison with results of actual analysis, and about ${\pm}$1.5% by the author's one.

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Implementation of Image Processing System for the Defect Inspection of Color Polyethylene (칼라팔레트의 불량 식별을 위한 영상처리 시스템 구현)

  • 김경민;박중조;송명현
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.6
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    • pp.1157-1162
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    • 2001
  • This paper deals with inspect algorithm using visual system. One of the major problems that arise during polymer production is the estimation of the noise of the color product.(bad pallets) An erroneous output can cause a lot of losses (production and financial losses). Therefore new methods for real-time inspection of the noise are demanded. For this reason, we have presented a development of vision system algorithm for the defect inspection of PE color pallets. First of all, in order to detect the edge of object, the differential filter is used. And we apply to the labelling algorithm for feature extraction. This algorithm is designed for the defect inspection of pallets. The labelling algorithm permits to separate all of the connected components appearing on the pallets. Labelling the connected regions of a image is a fundamental computation in image analysis and machine vision, with a large number of application. Also, we suggested vision processing program in window environment. Simulations and experimental results demonstrate the performance of the proposal algorithm.

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Effect of Baegi-eum (BGU) on mepirizole-induced gastrointestinal tissue injury in rabbit (배기음(排氣飮)이 Mepirizole에 의해 유발된 토끼의 위장관 손상에 미치는 영향)

  • Kim, Woo-Hwan;Kim, Won-Ill
    • The Journal of Internal Korean Medicine
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    • v.22 no.1
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    • pp.21-27
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    • 2001
  • 목적 : 본 연구는 배기음(排氣飮)이 토끼의 위장관내에서 화학물질에 의해 유발된 장관의 궤양에 유효한 효과를 발휘할 수 있는지를 검증하기 위한 실험이다. 방법 : 토끼 5마리를 한 군으로 하여 정상군과 체중 1kg당 200mg 분량의 mepirizole을 경구 투여한 군과 100mg/kg의 배기음(排氣飮)(경구투여)과 800Units/kg 분량의 catalase(정맥주사)를 mepirizole을 경구투여하기 2시간 전에 각각 전처치한 군으로 나누었다. Mepirizole을 경구 투여한 후 각각 24hr와 48hr에 토끼를 희생시켜 위장, 십이지장부의 궤양성 병변을 관찰하였다. 결과 : Mepirizole을 경구투여하여 위장 및 십이지장 기부의 궤양성 병변이 유발되었다. 배기음(排氣飮)(경구투여)과 catalase(정맥주사)를 전처치하였을 경우 궤양의 크기가 현저하게 줄어들었다. Mepirizole은 십이지장 점막에서 지질의 과산화를 증가시키는데 이는 수산화기와 관련되어 있음을 시사한다. 배기음(排氣飮)과 catalase를 전처치함으로써 mepirizole에 의해 유발된 지질의 과산화가 현저하게 억제되었다. 형태학상의 연구에서도 mepirizole의 처치에 의한 십이지장의 손상과 배기음(排氣飮)에 의한 방지효과가 나타났다. 결론 : 이러한 결과들로 볼 때 반응성산소기는 mepirizole에 의해 유발된 위장관 궤양의 병리변화 형성에 주요한 영향을 미치며 배기음(排氣飮)이 항산화작용을 통해 궤양의 형성을 억제하는 역할을 하고 있음을 나타낸다. 따라서 본 연구는 배기음(排氣飮)이 반응성산소기에 의해 매개된 인체 위장관질환에 치료적 역할을 할 수 있음을 제시하고 있다.

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Effect of Kamihaengche-tang Plus Yukmijihwang-tang Oxidant-induced Liver Cell injury (Oxidant에 의한 간독성유발에 가미행체엽탕 합 육미지황탕의 효과)

  • 이수행;김우환
    • Journal of Life Science
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    • v.8 no.4
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    • pp.464-471
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    • 1998
  • This study was carried out to determine whether Kamihaengche-tang plus Yukmijihwang-tang (KCYH) exerts the protective effect against oxidant-induced liver cell injury. Cell injurt was estimated by measuring lactate dehydrogenase (LDH) and alanine aminotransferase (ALT) release, and lipid peroxidation was estimated by measuring malondialdehyde, a product of lipid peroxidation in rabbit liver slices. $H_2O_2$increased LDH release which was significantly prevented by 1% KCYHT. The protective effect of KCYH against $H_2O_2$-induced cell injury was dose-dependent in the range of 0.05-1% concentrations. Similary, KCYH inhibited $H_2O_2$ induced lipid peroxidation in a dose-dependent manner. When liver tissuse were exposed to Hg(0.5 mM), ALT activity in the medium and lipid erpoxidation in tissues were markedly increased. These changes were prevented by 1% KCYH. KCHY restored Hg-induced inhibition of cellular GSH content. These result indicate that KCYH exerts the protective effect oxidant-induced liver cell injury, and this effect is attributed to prevented to prevention of lipid peroxidation. These dffects may be due to an increase in concentration of endogenous antioxidants.

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A Study of Relationship Knowledge, Depression and Quality of Life of Mothers with Hemophilic Children (혈우환아 어머니의 혈우병 관련 지식, 우울 및 삶의 질과의 관계연구)

  • Song, Young-A;Kang, Hyun-Sook;Kim, Won-Ok
    • Women's Health Nursing
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    • v.12 no.2
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    • pp.150-155
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    • 2006
  • Purpose: This study was conducted to survey knowledge, depression, and quality of life of mothers with hemophilic children, and to provide basic data for a health promoting intervention improving their quality of life. Method: The subjects of this study were 140 mothers of hemophilic children by convenience sampling. The collected data were processed using SPSS program and analyzed using descriptive statistics, and Pearson correlation. Result: The knowledge of mothers with hemophilic children was 2.8 points out of 4 points. The depression of the subjects was 2.1 points out of 4 points. The quality of life of the subjects was 3.2 points out of 5 points. Results also showed a positive relationship between quality of life and knowledge (r=.45, p<.001) and a negatives relationship between quality of life and depression (r=-.41, p<.001). Conclusion: Knowledge and depression affect quality of life of mothers with hemophilic children. Therefore, it is necessary to develop a nursing intervention with these variables to increase the quality of life for mothers with hemophilic children.

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Godel's Theorem and Mind as Turing Machine (튜링 기계로서의 마음과 괴델의 정리)

  • HwanSunwoo
    • Korean Journal of Cognitive Science
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    • v.6 no.3
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    • pp.5-23
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    • 1995
  • According to a well-known argument (so-called the Godelian argument) proposed by Lucas. Godel's theorem refutes the thesis of mechanism. that is, the thesis that human cognitive system is no more than a Turing machine. The main aim of this paper is to show that this argument is not successful. However. I also argue that many pre-existing objections (by Benacerraf, Slezak. Boyer. Hofstadter etc.) to Gooelian argument are not satisfactory. either. Using Tarski's theorem. I then strengthen what I caII the consistency objection to Godelian argument. In my dilemma objection obtained. Godelian argument doesn't work because the argument has a false premise if we have the concept of global truth and the argument cannot be stated if not.

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An Analysis of Willingness to Pay for Agricultural Experience of Daegu Urban Agriculture Park (대구 도시농업공원 농업체험에 대한 적정 체험금액분석)

  • Lin, Qing-Long;Lee, Soon-Seok;Jang, Woo-Whan
    • Journal of Korean Society of Rural Planning
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    • v.20 no.3
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    • pp.101-110
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    • 2014
  • As a rise in national income has resulted in the growth in tourism demand, many studies on developing and managing tourism resources were publicized. In this context, this study was conducted to analyze the demand and willingness to pay(WTP) using contingent valuation method for agricultural experience of Daegu Urban Agriculture Park and to suggest a proper participation fee. The survey targeting Daegu citizens was performed, and we obtained 346 valid samples. We carried out the logistic analysis and figured out that sex, age, education and alienation area for urban agriculture affected to probability of agricultural experience participation. As the result of estimating willingness to pay(WTP), the measured range with this samples was from 6,052 to 16,436won. Finally, we also attained 25,000won as the proper participation fee which enables maximum revenue by conducting the scenario analysis. These findings are important in setting up the construction plan and pricing the appropriate participation fee for Daegu Urban Agriculture Park.

Balaguer's Mathematical Platonism and the Epistemological Problem (밸러궈의 수학적 플라톤주의와 인식론적 문제)

  • Sunwoo, Hwan
    • Korean Journal of Logic
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    • v.18 no.1
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    • pp.39-64
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    • 2015
  • The most difficult problem for mathematical Platonism is the epistemological problem raised by Paul Benacerraf and Hartley Field. Recently, Mark Balaguer argued that his version of mathematical Platonism, Full Blooded Plantonism (FBP), can solve the epistemological problem. In this paper, I show that there are serious problems with Balaguer's argument. First, I analyse Balaguer's argument and reveal a formal defect in his argument. Then I raise an objection based on an analogical argument. Finally, I disarm some potential moves from Balaguer.

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The Effects of Grain Size on the Degradation Phenomena of PZT Ceramics (입자의 크기가 PZT 세라믹스의 열화현상에 미치는 영향)

  • 정우환;김진호;조상희
    • Journal of the Korean Ceramic Society
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    • v.29 no.1
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    • pp.65-73
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    • 1992
  • The effect of grain size on the time-dependent piezoelectrice degradation of a poled PZT of MPB composition Pb0.988Sr0.012 (Zr0.52Ti0.48)O3 with 2.4 mol% of Nb2O5 was studied, and the degradation mechanism was discussed. Changes in the internal bias field and the internal stress both responsible for the time-dependent degradation of poled PZT were examined by the polarization reveral technique, XRD and Vickers indentation, respectively. The piezoelectric degradation increased with increasing time and grain size, and the internal bias field due to space charge diffusion decreased with increasing grain size of poled PZT. The internal bias field, however, was almost insensitive to the degradation time regardless of the grain size. On the other hand, both the x-ray diffraction peak intensity ratio of (002) to (200) and the fracture behavior including the crack propagation support that the ferroelectric domain rearrangement of larger grain size showed rapid relaxation of the internal stress compared with smaller one, which is thought the origin of the larger piezoelectric degradation in the former. In conclusion, the contribution of space charge diffusion on the piezoelectric degradation of PZT is strongly dependent on both the grain size and the composition. Thus, the relaxation of internal stress due to the ferroelectric domain rearrangement as well as the amount and time-dependence of the internal bias field due to space charge diffusion should be considered simultaneously in the degradation mechanism of PZT.

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