• 대기
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• 제34권2호
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• pp.139-151
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• 2024

The Yeongdong region has suffered from severe snowstorms and the relevant damage such as traffic accidents on slippery roads, and the collapse of greenhouses and temporary buildings. While a lot of research on snowfall has been conducted, the detailed study of snow crystals' phase and habit through intensive observations and the relevant microphysical analysis is still lacking. Therefore, a snowflake camera, PARSIVEL, and intensive radiosonde soundings were utilized to investigate phase and habit changes in solid precipitation. Two remarkable episodes of phase and habit changes were selected such as 19 March 2022 and 15 February 2023. Both events occurred in the synoptic condition of the High in the north and the Low passing by the south, which was accompanied by rapid temperature cooling below 2.5 km. During the events of a short period between 3 to 6 hours, the temperature at 850 hPa decreased by about 4 to 6℃. This cooling led to a change in the main habit of snow particles from riming to aggregate, identified with both MASC and PARSIVEL. Meanwhile, the LDAPS model analyses do not successively represent the rapid cooling and short-term variations of solid precipitation, probably by virtue of overestimating low-level equivalent potential temperature during these periods. The underlying causes of these the low-level temperature variations within 6 hours, still remain unclear. It might be associated with mesoscale orographic phenomenon due to the mountains and East Sea effects, which certainly needs an intensive and comprehensive observation campaign.

• Journal of Pharmaceutical Investigation
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• 제34권6호
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• pp.443-452
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• 2004

Habit is the description of the outer appearance of a crystal. If the environment of a growing crystal affects its external shape without changing its internal structure, a different habit results. Crystal habit and the internal structure of a drug can affect bulk and physicochemical properties, which range from flowability to chemical stability. A polymorph is a solid crystalline phase of a given compound resulting from the possibility of at least two different arrangements of the molecules of that compound in the solid state. Chemical stability and solubility changes due to polymorphism can have an impact on a drug's bioavailability and its development program. During crystallization from a solution, crystals separating may consist of a pure component or be a molecular compound. Solvates are molecular complexes that have incorporated the crystallizing solvent molecule in their lattice. When the solvent incorporated in the solvate is water, it is called a hydrate. To distinguish solvates from polymorphs, which are not molecular compounds, the term pseudopolymorph is used. Identification of possible hydrate compounds is important since their aqueous solubilities can be significantly less than their anhydrous forms. Conversion of an anhydrous compound to a hydrate within the dosage form may reduce the dissolution rate and extent of drug absorption. An amorphous solid may be treated as a supercooled liquid in which the arrangement of molecules is random. Amorphous solids lack the three-dimensional long-range order found in crystalline solids. Since amorphous forms are usually of higher thermodynamic energy than corresponding crystalline forms, solubilities as well as dissolution rates are generally greater. A study on crystal form includes characterization of (l)crystal habit, (2)polymorphism, (3)pseudopolymorphism, (4)amorphous solid.

• 디지털융복합연구
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• 제12권11호
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• pp.225-232
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• 2014

네트워크와 통신의 발달로 스마트 디바이스의 보급이 이루어졌으며, 삶의 질을 높이기 위한 사람들의 열망이 커지면서 서비스 산업이 스마트 디바이스를 통해 이루어지고 있다. 그 중에서도 사람들의 건강한 삶을 위해 행동을 변화할 수 있도록 도와주는 서비스가 일반적인 프로세스로 개발되어져 행위자의 행동 변화에 대해 많은 영향을 미치지 못한다. 따라서 본 연구는 애플리케이션 마켓을 통해 현재 행동변화 애플리케이션에 대한 개발 상황을 알아보았다. 개발현황에는 프로세스에 의해 2가지 패턴으로 나눌 수 있다. 이 결과와 행동 이론 모델인 통합변화모델, 목표설정이론의 목표 수행 과정과 이를 자동화시키기 위한 습관형성단계를 사용한 행동변화모델을 제시한다. 또한, 모델에 따른 서비스를 제시하여 행위자에게 동기력 및 행동의 지속가능성과 긍정적으로 행동 변화가 이루어 질 수 있도록 한다. 이렇게 구성함으로써 기존의 서비스보다 행동력 동기력 등 여러 측면에서 기대할 수 있을 것이다.