• Title/Summary/Keyword: S&T

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The Study of the Dielectric and Piezoeletric Properties of 0.05Pb(AlS12/3TWS11/3T)OS13T-0.95Pb(ZrS10.52TTiS10.48T)OS13T System Modified with MnOS12T and FeS12TOS13T (MnO2, Fe2O3 첨가에 따른 0.05Pb(Al2/3W1/3)O3-0.95Pb(Zr0.52Ti0.48)O3계의 유전 및 압전 특성에 관한 연구)

  • 윤석진;오현재;정형진
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.41 no.5
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    • pp.508-516
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    • 1992
  • In this study, dielectric and piezoelectric properties of 0.05Pb(AlS12/3TWS11/3T)OS13T-0.95Pb(ZrS10.52TTiS10.48T)OS13T system ceramics were investigated with respect to the variations of MnOS12T and FeS12TOS13T additions amounts. The results obtained in this study are summarized as follows: 1. As the amounts of MnOS12T and FeS12TOS13T are increased, tetragonality(c/a) and apparent density were decreased but grain size was increased, also the limits of solubility were revealed because pores were formed at the amounts of 0.3wt% MnOS12T and 0.5wt% FeS12TOS13T. 2. AS the increasing of amounts of MnOS12T and FeS12TOS13T, the temperature of phase transition(TS1cT) was decreased, and pemeability had maximum value at the amount of 0.3wt% MnOS12T but were sharply decreasd for the increasing FeS12TOS13T amounts. 3. As the amounts of MnOS12T and FeS12TOS13T are increased, the electro-mechanical coupling factor(kS1pT) was decreased from 60% to 41%, 19% respectively, but mechanical quality factor(QS1mT) had maximum values 720 for amount of 0.3wt% MnOS12T and 320 the amount of 0.5wt% FeS12TOS13T.

Spectral Properties of k-quasi-class A(s, t) Operators

  • Mecheri, Salah;Braha, Naim Latif
    • Kyungpook Mathematical Journal
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    • v.59 no.3
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    • pp.415-431
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    • 2019
  • In this paper we introduce a new class of operators which will be called the class of k-quasi-class A(s, t) operators. An operator $T{\in}B(H)$ is said to be k-quasi-class A(s, t) if $$T^{*k}(({\mid}T^*{\mid}^t{\mid}T{\mid}^{2s}{\mid}T^*{\mid}^t)^{\frac{1}{t+s}}-{\mid}T^*{\mid}^{2t})T^k{\geq}0$$, where s > 0, t > 0 and k is a natural number. We show that an algebraically k-quasi-class A(s, t) operator T is polaroid, has Bishop's property ${\beta}$ and we prove that Weyl type theorems for k-quasi-class A(s, t) operators. In particular, we prove that if $T^*$ is algebraically k-quasi-class A(s, t), then the generalized a-Weyl's theorem holds for T. Using these results we show that $T^*$ satisfies generalized the Weyl's theorem if and only if T satisfies the generalized Weyl's theorem if and only if T satisfies Weyl's theorem. We also examine the hyperinvariant subspace problem for k-quasi-class A(s, t) operators.

A Study of Garlic-Yackwa Development 1. Quality Characteristics of Garlic-Yackwa Substituted with Different Amounts of Garlic Juice (마늘약과의 개발에 관한 연구 1. 마늘즙 대체량을 달리한 마늘약과의 품질특성)

  • 문숙임
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.32 no.8
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    • pp.1285-1291
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    • 2003
  • This study was carried out to find optimum substitution amounts of garlic juice for the purpose of garlic-Yackwa development. Five experimental groups containing 0 t.s, 1/2 t.s, 1 t.s, 1 and 1/2 t.s, and 2 t.s of garlic juice per 1 cup of flour were compared with basic group containing 2 t.s of ginger juice per 1 cup of flour (ginger-Yackwa), by Hunter's colorimetry, texture profile analysis and sensory evaluation. In Hunter's color value, Yackwa, substituted garlic juice from 1/2 t.s to 2 t.s per 1 cup of flour for ginger juice, were lower than ginger-Yackwa. The higher amounts of garlic juice in garlic-Yackwa showed the lower tendancy of L and a values. The b value of garlic-Yackwa containing from 0 t.s to 2 t.s of garlic juice was higher than that of ginger-Yackwa. The higher amounts of garlic juice in garlic-Yackwa showed the higher tendancy of b value. In the texture characteristics, hardness, adhesiveness, springiness and chewiness of all garlic-Yackwa were significantly lower than those of ginger-Yackwa. Cohesiveness of garlic-Yackwa containing from 1 t.s to 2 t.s of garlic juice was significantly higher than that of ginger-Yackwa. Gumminess of Yackwa with garlic juice was higher ($1_{1/2}$ t.s, 2 t.s) than that of ginger-Yackwa, or lower (0 t.s∼l t.s) than that of ginger-Yackwa. The higher amounts of garlic juice in garlic-Yackwa showed the higher tendancies of hardness, cohesiveness and gumminess, while springiness and chewiness showed vice versa. In sensory evaluation, the higher amounts of garlic juice in garlic-Yackwa showed the better color, appearance, flavor, taste and overall acceptability. Especially garlic-Yackwa with 2 t.s of garlic juice showed the best color, appearance, taste, overall acceptability among them. Garlic-Yackwa with 2 t.s of garlic juice evaluated the best, while ginger-Yackwa evaluated the worst. In conclusion, these results indicated that 2 t.s of garic juice per 1 cup of flour could be very useful as a substitute for ginger juice in developing garlic-Yackwa.

How to Improve the Welfare of Science & Technology Personnel: Based on the Construction of Comprehensive Welfare Town for S&T Personnel (과학기술인의 종합복지 제고 전략: 과학기술인 종합복지타운 건립을 중심으로)

  • Jeong, Seon-Yang;Lee, Jong-Min
    • Journal of Technology Innovation
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    • v.14 no.3
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    • pp.155-182
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    • 2006
  • Science & Technology(S&T) personnel have been Playing a major role to develop our country since S&T is the most important factor in enhancing national competitiveness in the 21st century, As S&T activities are done by S&T personnel, it is essential to improve the welfare of S&T personnel in order to increase the performance of S&T activities. We should motivate them to pour their efforts and energy in S&T activities. However, the issue of S&T personnel's welfare has not been discussed sufficiently not only in academic research, but also in actual S&T policies. It has caused many social problems, for example, avoidance of S&T areas by young generation, low social recognition of S&T community, and so on. Under this background, this paper aims at investigating how to effectively improve S&T personnel's welfare. In this paper, we will suggest the 'Comprehensive Welfare Town for S&T personnel' as an effective instrument for improving of S&T personnel's welfare. In particular, we will discuss the detailed aspects of the comprehensive welfare town : objectives, strategies and budgets.

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EXTENSIONS OF NAGATA'S THEOREM

  • Hamed, Ahmed
    • Journal of the Korean Mathematical Society
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    • v.55 no.4
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    • pp.797-808
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    • 2018
  • In [1], the authors generalize the concept of the class group of an integral domain $D(Cl_t(D))$ by introducing the notion of the S-class group of an integral domain where S is a multiplicative subset of D. The S-class group of D, $S-Cl_t(D)$, is the group of fractional t-invertible t-ideals of D under the t-multiplication modulo its subgroup of S-principal t-invertible t-ideals of D. In this paper we study when $S-Cl_t(D){\simeq}S-Cl_t(D_T)$, where T is a multiplicative subset generated by prime elements of D. We show that if D is a Mori domain, T a multiplicative subset generated by prime elements of D and S a multiplicative subset of D, then the natural homomorphism $S-Cl_t(D){\rightarrow}S-Cl_t(D_T)$ is an isomorphism. In particular, we give an S-version of Nagata's Theorem [13]: Let D be a Krull domain, T a multiplicative subset generated by prime elements of D and S another multiplicative subset of D. If $D_T$ is an S-factorial domain, then D is an S-factorial domain.

On the Gauss Map of Tubular Surfaces in Pseudo Galilean 3-Space

  • Tuncer, Yilmaz;Karacan, Murat Kemal;Yoon, Dae Won
    • Kyungpook Mathematical Journal
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    • v.62 no.3
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    • pp.497-507
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    • 2022
  • In this study, we define tubular surfaces in Pseudo Galilean 3-space as type-1 or type-2. Using the X(s, t) position vectors of the surfaces and G(s, t) Gaussian transformations, we obtain equations for the two types of tubular surfaces that satisfy the conditions ∆X(s, t) = 0, ∆X(s, t) = AX(s, t), ∆X(s, t) = λX(s, t), ∆X(s, t) = ∆G(s, t), ∆G(s, t) = 0, ∆G(s, t) = AG(s, t) and ∆G(s, t) = λG(s, t).

A Study on the Improvement of Pyroelectric Coefficient in the PSS-PT-PZ Infrared Sensor (PSS-PT-PZ 적외선 센서의 초전계수향상에 관한 연구)

  • 이성갑;배선기;이영희
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.41 no.6
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    • pp.652-660
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    • 1992
  • 0.10Pb(SbS11/2TSnS11/2T)OS13T-0.25PbTiOS13T-0.65PbZrOS13T ceramics modified by LaS12TOS13T(1[mol%]) and MnOS12T(0-0.30[mol%]) were fabricated. The structural and pyroelectric properties with contents of MnOS12T were studied. Crystal structure of a specimen was rhombohedral type and average grain sizes were decreased with increasing the contents of MnOS12T. Relative dielectric constant and dielectric loss factor were minimum in the specimens doped 0.24[mol%]MnOS12T. (PbS10.99TLaS10.01T)[(SbS11/2TSnS11/2T) TiS10.25TZrS10.65T]OS13T specimen modified 0.24[mol%]MnOS12T showed the good pyroelectric properties and pyroelectric coefficient and voltage responsivity were 6.73x10S0-8T[C/cmS02TK], 125[V/W], respectively. Voltage responsivity was increased with decreasing the chopper frequency.

How to Improve the Welfare of Science & Technology Personnel : Based on the Comprehensive Welfare Town for S&T Personnel (과학기술인의 종합복지 향상방안 : 과학기술인 종합복지타운 건립을 중심으로)

  • 이종민;임상현;정선양
    • Proceedings of the Technology Innovation Conference
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    • 2006.02a
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    • pp.150-169
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    • 2006
  • Science & Technology (S&T) personnel have played a major role to develop our country since S&T is the most important factor to increase national competitiveness in the 21st century. Therefore, it is very essential to increase the welfare of S&T personnel in order to increase national S&T and economic competitiveness. However, the welfare of S&T personnel has not been discussed sufficiently not only in academic research, but also in actual S&T policies. It has caused many. social problems (for example, avoiding fields of S&T of young generation, low social recognition of S&T community and so on). Under this background, this paper aims at investigating how to effectively improve S&T personnel's welfare. For this purpose, we deal with a theoretical review on the welfare of S&T personnel. After that, we will suggest 'Comprehensive Welfare Town for S&T Personnel' as a method of improving the welfare of S&T personnel.

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A Study on the Reform of Korean S&T Related Law (과학기술관계법제의 정비방안 연구)

  • 송종국;오준근
    • Journal of Technology Innovation
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    • v.2 no.1
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    • pp.142-169
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    • 1994
  • Korean Government has established a lot of S&T laws to promote National Science and Technology since established the Ministry of S&T and the S&T Promotion Law in 1967. There are more than ninties of S&T related laws to support Government's S&T policies recently. Even though Korean Government has enacted plenty of S&T related laws are required to be reformed. In this paper, firstly, we define what is S&T related law and the relationship between S&T related law system. Secondly, we investigate the problems of S&T related law with respect to several aspects such as historical, executing, international environment, and systematic aspects. Finally, we suggest the directions of S&T law reform. We conclude that S&T laws need to be merged and abolished in some areas such as various council system and S&T incentive system especially related to UR restriction.

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