• 자연과학논문집
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• 제10권1호
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• pp.63-71
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• 1998

Azalea의 개화조절을 위하여 차광, 저온 및 지베레린을 처리한 결과는 다음과 같다. 차광처리에 따른 개화반응에 있어서 차광을 많이 할수록 공시품종 모두 개화기간이 연장되었고 개화수는 증가하였다. 또한 개화소요일수는 'Ripple'에서만 증가되었으며 나머지 2품종은 비슷하였다. 저온처리는 'Inga'와 ‘Ripple'에서 개화소요일수와 개화수를 크게 증가 시켰으며 ’Reinhold Ambrosia'에서는 오히려 개화소요일수를 단축시켰다. 차광과 저온의 조합처리의 경우 저온처리후 차광처리가 높을수록 ‘Inga'와 ’Ripple'은 개화소요일수와 개화수는 증가하였으나, ‘Reinhold Ambrosia'에서는 개화소요일수와 개화기간이 단축되었고 개화수는 증가하였다. $GA_3$ 처리에 따른 개화반응에 있어서 지베렐린 처리농도가 높아질수록 ’Ripple'과 ‘Reinhold Ambrosia'는 개화소요일수가 뚜렷이 단축되었고 개화기간은 증가하였으나 'Inga'에서는 별다른 차이가 없었다. 개화수는 ’Inga'와 ‘Ripple'에서 증가하였다. 이와같이 azalea에 차광, 저온 및 지베레린을 처리하므로서 개화기간이 연장되고, 개화수는 증가하는데 비해 개화소요일수는 품종에 따라 다르게 나타났다.

• 한국세라믹학회지
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• 제23권2호
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• pp.64-70
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• 1986

In this investigation x-ray diffraction method was mainly studied for quantitative analysis of clinker mineral composition. And also optical microscopic observation and Bogue calculation method were applied to compare with the x-ray diffraction method. In the procedure of x-ray diffraction analysis graphite monochromator automatic divergence slit and spinner for sample holder were used for minimizing the error due to the operation of the equipment. Especially the separation of overlapped peaks were proceeded by micro-processor automatically. The results of x-ray diffraction method for synthesized clinker were consistent with the Bogue value and the results of optical microscopic observation. However the results of quantitative analysis of mineral composition or commercial clinker containing solid solution of minor component were different from the Bogue value. On the other hand they agreed reasonably well with results of the optical mic-roscopic observation.

• Bulletin of the Korean Chemical Society
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• 제27권2호
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• pp.211-218
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• 2006

This work deals with 24 substances composed of nitrogen-containing heterocycles. The relationships between the chromatographic retention factor (k) and those physicochemical properties which are relevant in quantitative structure-properties relationship (QSPR) studies, such as the polarizability $(\alpha)$, molar refractivity (MR), lipophilicity (logP), dipole moment $(\mu)$, total energy $(E_{tot})$, heat of formation $(\Delta H_f)$, molecular surface area $(S_M)$, and binding energy $(E_b)$, were investigated. The accuracy of the simple linear regressions between the chromatographic retention and the descriptors for all of the compounds was satisfactory (correlation coefficient, $0.8 \leq r \leq 1.0$). The QSPR models of these nitrogen-containing heterocyclic compounds could be predicted with a multiple linear regression equation having the statistical index, r = 1.000. This work demonstrated the successful application of the multiple linear approaches through the development of accurate predictive equations for retention factors in liquid chromatography.

• Bulletin of the Korean Chemical Society
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• 제34권12호
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• pp.3859-3862
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• 2013

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.520-539
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• 2003

By using sequentially efficacy tests based on tyrosinase, the key enzyme of melanogenesis, then a cell line of melanocytes cultured in vitro, we have been able to detect the whitening potential of a plant extract and then to develop a new whitening Active Ingredient whose the whitening potential was confirmed on cultured melanocytes. Through a phytochemical approach, it seems that the whitening potential could be due to the "tannin" fraction of plant extract. A complementary work is planned to explain more precisely which fractions are responsible for the whitening potential and a clinical test is in progress on 30 Asian skin type volunteers to show the whitening efficacy on human volunteers.

• 설비공학논문집
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• 제17권10호
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• pp.883-890
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• 2005

In this study, 2 pure hydrocarbon refrigerants of R1270 (Propylene) and R290 (Propane) and 3 binary mixtures composed of R1270, R29O and R152a were tested in a refrigerating bench tester with a scroll compressor in an attempt to substitute R502 used in most of the low temperature applications. The test bench provided 3\sim3.5$ kW capacity and water and water/glycol mixture were employed as the secondary heat transfer fluids. All tests were conducted under the same external conditions resulting in the average saturation temperatures of -28 and $45^{\circ}C$ in the evaporator and condenser, respectively. Test results showed that all refrigerants tested had $9.6\sim18.7\%$ higher capacity and $17.1\sim27.3\%$ higher COP than R502. The compressor discharge temperature of R1270 was similar to that of R502 while those of all other refrigerants were $23.7\sim27.9\%$ lower than that of R502. For all alternative refrigerants, the amount of charge was reduced up to $60\%$ as compared to R502. Overall, these alternative refrigerants offer better system performance and reliability than R502 and can be used as long term substitutes for R502 due to their excellent environmental properties.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 춘계종합학술대회
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• pp.124-127
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• 2003

본 논문에서는 초광대역 무선 통신에 안티포달 펄스 신호를 이용하고, 기존의 초광대역 시간도약 모노펄스 통신에서 규칙적인 펄스를 전송할 때 발생하는 전력 스펙트럼에서의 에너지 스파크 현상을 완화시키기 위하여 의사잡음 부호와 왈쉬 부호를 사용하였을 때의 전력 스펙트럼 특성을 비교, 분석하였다. 그 결과, 초광대역 안티포달 임펄스 통신에서의 두 가지 부호 방식의 이용으로 에너지 스파크 현상이 완화되고 고속의 시간도약 부호를 이용하지 않더라도 완만한 전력스펙트럼 특성을 얻을 수 있었다.

• 현장농수산연구지
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• 제22권1호
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• pp.131-142
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• 2020

전 세계적으로 국화에 큰 피해를 야기하는 국화왜화바이로이는 단일나선형의 감염성 RNA 병원체로, 1997년 국내에서 처음 발견된 이후 전국적으로 빠르게 전파되고 있다. 그러나 이러한 심각성 에도 불구하고, 국화왜화바이로이드는 재배적, 화학적 방제가 불가능하기 때문에 예방 이외에는 방제할 수 있는 방법이 거의 없는 실정이다. 따라서 국화 재배에 있어 국화왜화바이로이드병을 방제하기 위해서는 저항성 품종의 육성이 절실하다. 이에 본 연구에서는 국화왜화바이로이드 저항성 품종 육성을 위한 기반 구축을 위해 유전자원을 선발하고자 하였다. 스프레이 167 품종과 스탠다드 25품종 등 총 192 품종을 공시하여 접목즙액접종법을 통해 병 저항성 검정을 실시한 결과, 대부분의 품종에서 초장이 감소하는 전형적인 왜화 증상을 나타냈으며, 화경이 감소하고 화색이 퇴화되는 증상을 보였다. 그러나 일부 품종에서는 이와 같은 병징이 나타나지 않거나 지연되는 경향을 보였다. 192 품종 가운데 5% 이하의 초장 감소율을 보인 'Chiwerel'과 'Jeongheungdaesin'은 저항성, 20% 미만의 초장감소율을 보인 'Inga' 등 6 품종은 중도저항성, 그리고 그 외 184품종은 감수성으로 평가되었다. 저항성 발현이 안정적으로 나타나는 'Chiwerel' 등의 품종들은 국화왜화바이로이드병 저항성 품종을 육종하는 교배모본으로 활용될 수 있을 것으로 기대된다.

• 복식
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• 제62권5호
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• pp.16-30
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• 2012

This study examines the types and features of formal ritual hats for Tibetan Buddhist priests. Findings of the study are as follows. The types of formal hats that Tibetan Buddhist priests wear during religious rites or rituals include: u rgyan pad zhwa, pan zhwa, tshogs zhwa, rigs inga, zhwa nag, zhwa dmar and dwags zhwa. The reason why such formal ritual hats as listed above were developed is because the region had an alpine climate, and also because they were the symbolism of Buddhism, the most reverent priest, and reincarnated Buddha thoughts. They were an essential part of the culture of dressing Buddhist statues and offering utensils. Formal ritual hats' shapes originate from lotus. They are colored in red, yellow, indigo, green, white or black, that reflect the nationality and aesthetics of Tibetans. They are mainly made of woolen or silk fabrics. They are usually decorated with gold, git bronze or jewels and the patterns of the sun and the moon, vajra or clouds.

• 한국세라믹학회지
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• 제28권6호
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• pp.457-464
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• 1991

Aluminum nitride (AlN) has excellent properties such as high thermal conductivity and electrical resistivity, whereas it has some disadvantages such as low sinterability and tendency to be hydrolyzed by moisture at room temperature. In the present work, the relative density, modulus of rupture and microhardness were examined for pressure-less-sintered AlN (synthetic and commercial) bodies which were prepared under the conditions of various sintering temperatures, holding times and additions of CaCO3 which showed the best effect on sinterability among the various sintering aids. As a result, the AlN bodies with 1.0 wt% CaCO3 (0.56wt% CaO) which were sintered at 1800$^{\circ}C$ for 20 min showed good densification. In this case, the relative densities were 95.9% and 95.2%, and microhardnesses were 10.3 GPa and 9.8 GPa for synthetic and commercial AlN respectively. And as the holding time at 1800$^{\circ}C$ was increased from 10 min to 60 min, the relative density was increased from 91.9% to 96.5%. It was considered that impurities of metals and oxygen promoted the densification of AlN at low temperature (1600$^{\circ}C$).