• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.10 no.4
• /
• pp.302-308
• /
• 2000

Stable amorphous calcium carbonate were synthesized from the serial work for the synthetic conditions such as concentration of solution, reaction temperature, aging time and pH of mother liquor. By using this as a precusor, calcite, aragonite and vaterite crystal particles were obtained in the water from adequate crystallization conditions. Furthermore, characterization for flourescence were performed by using crystals which were crystallized from the Sn dopped amorphous calcium carbonate. Calcite showed the most intensive emission and the center of emission wavelength was 464 nm with pure blue color. Calcite is expected to be used as phosphor for flourescent lamp because the maximum emission intensity was obtained from the excitation with 255 nm wavelength.

• The Journal of Korean Association of Computer Education
• /
• v.16 no.4
• /
• pp.1-11
• /
• 2013

The purpose of this study is to investigate a structural relationship among elementary students' self-determinant learning motivation, teaching-presence and learning outcomes (learning satisfaction, persistence) in blended learning environment. Participants were 5th and 6th grade students who enrolled in a mathematics learning service. The results showed that self-determinant learning motivation had direct effect on teaching presence, learning satisfaction and learning persistence. Teaching Presence had an direct effect on learning satisfaction and learning satisfaction had an direct effect on learning persistence. Based on the results, proper strategies were recommended to facilitate self-determinant learning motivation and teaching presence before and during learning since they play critical roles for the success of elementary students learning outcomes in a blended learning environment.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.8 no.4
• /
• pp.475-482
• /
• 2020

In this study, three levels of solid capsules were prepared according to the composition ratio of core materials for the crystal growth type self-healing solid capsule, and a cement mortar was prepared with the crystal growth type self-healing solid capsule. The prepared solid capsule was mixed with 3% of the cement mass to evaluate the healing properties according to the crack induction age of the cement mortar. As a result of test, the crack healing properties according to the crack induction age of cement mortar mixed of solid capsules, it was confirmed that the self-healing performance of the cement mortar with the solid capsules was increased self-healing performance of 7 days than 28 days. This is because the unhydrated binder remains.

• Korean Journal of Crystallography
• /
• v.7 no.2
• /
• pp.183-190
• /
• 1996

Single crystals of ZnO were grown hydrothermally with KOH solution in silver lined autoclave. The effect of LiOH and NH4OH on the morphology of as-grown crystals was studied. As-grown crystals were pale green and the maximum size was 30×30×20mm3. Addition of LiOH reduced the density of flaws on the (0001) face of as-grown ZnO crystals. In highly concentrated KOH solution, ZnO had a strong tendency to grow along the c-axis. When 1.0-2.0 M of NH4OH was added into mineralizer, growth rate along the direction of a-axis increased. From this result, ZnO single crystals of equant-faced hexagonal prism could be grown with acicular seeds.

• Clean Technology
• /
• v.12 no.3
• /
• pp.157-164
• /
• 2006

In order to purify 2-methylnaphthalene as main impurity included in naphthalene, SLE (solid-liquid equilibria) on two components system including naphthalene and 2-methylnaphthalene were measured and a layered melt crystallization has been studied. SLE in the present system is shown a simple eutectic mixture and the experimental results using DSC method is similar to the static method. Purity and yield of naphthalene in crystal depended mainly on the cooling rate: Increasing cooling rate, the purity of naphthalene in crystal increase, whereas the yield of that decrease. The effective distribution coefficient (Keff) as the degree of impurity removal was observed to decrease with decreasing of cooling rate. Therefore, the purity of naphthalene by melt crystallization can be enhanced to 5~7 %.

• The Journal of the Korea Contents Association
• /
• v.15 no.12
• /
• pp.355-369
• /
• 2015

Purpose: This study aimed to identify on the attitudes toward the life support care among elderly people using Q methodology. Methods: Thirty-nine elderly people classified 34 selected Q statements into a shape of normal distribution using a 9 point scale. The obtained data were analyzed by using a PQ Method PC program. Results: Principal component analysis identified 4 types of the attitudes toward the life support care among elderly people. Type I is "Situational & Self-determination linear type", type II is "Destiny & Life support care denied type", type III is "Avoidant & Family decision emphasis type" and type IV is "Respect for life & life support care approved type". Most of elderly people have been attitude that wish to receive honor their own decisions toward the prolongation treatment. Conclusion: The findings indicate a need to policy guidelines and public information that express self-determination of elderly people.

• Journal of KIISE
• /
• v.43 no.7
• /
• pp.801-811
• /
• 2016

Self-adaptive systems (SASs) can change their goals and behaviors to achieve its ultimate goal in a dynamic execution environment. Existing approaches have designed, at the design time, utility functions to evaluate and predict the goal satisfaction, and set policies that are crucial to achieve each goal. The systems can be adapted to various runtime environments by utilizing the pre-defined utility functions and policies. These approaches, however, may or may not guarantee the proper adaptability, because system designers cannot assume and predict all system environment perfectly at the design time. To cope with this problem, this paper proposes a new method of dynamic decision making, which takes the following steps: firstly we design a Dynamic Decision Network (DDN) with environmental data and goal model that reflect system contexts; secondly, the goal satisfaction is evaluated and predicted with the designed DDN and real-time environmental information. We furthermore propose a dynamic reflection method that changes the model by using newly generated data in real-time. The proposed method was actually applied to ROBOCODE, and verified its effectiveness by comparing to conventional static decision making.

• Applied Chemistry for Engineering
• /
• v.8 no.3
• /
• pp.389-394
• /
• 1997

The distribution of impurity included in benzene layer crystal was explored in layer crystallization of cyclohexane and benzene mixtures. The influence of crystal growth rate on crystal purity was investigated. All experimental results for bezene-cyclohexane system obtained in layer crystallizer have been evaluated with the criterion of Wintermantel. The purity of crystal decreases with increasing degree of subcooling, decreasing feed concentration and increasing crystal growth rate. The crystal growth rate was a key parameter to determine the inclusion of impurity in crystals. The results obtained from runs performed at increasing crystallization time(i.e. crystal thickness) have clearly shown that migration of inclusions within crystal layer to the melt, leading to the removal of impurity occurs. The diffusion of impurity which takes place during the crystallization from the beginning, enhances a further purification of the crystal layer if that underwent a thermal gradient after growth of the layer crystal stops.

• Annual Conference on Human and Language Technology
• /
• 2021.10a
• /
• pp.199-202
• /
• 2021

의미역 결정은 입력된 문장 내 어절간의 의미 관계를 예측하기 위한 자연어처리 태스크이며, 핵심 서술어에 따라 상이한 의미역 집합들이 존재한다. 기존의 연구는 문장 내의 서술어의 개수만큼 입력 문장을 확장해 순차 태깅 문제로 접근한다. 본 연구에서는 확장된 입력 문장에 대해 구문 분석을 수행 후 추출된 문장 구조 정보를 의미역 결정 모델의 자질로 사용한다. 이를 위해 기존에 학습된 구문 분석 모델의 파라미터를 전이하여 논항의 위치를 예측한 후 파이프라인을 통해 의미역 결정 모델을 학습시킨다. ALBERT 사전학습 모델을 통해 입력 토큰의 표현을 얻은 후, 논항의 위치에 대응되는 표현을 따로 추상화하기 위한 계층형 트랜스포머 인코더 레이어 구조를 추가했다. 실험결과 Korean Propbank 데이터에 대해 F1 85.59의 성능을 보였다.

• Proceedings of the Korea Crystallographic Association Conference
• /
• 2003.11a
• /
• pp.32-32
• /
• 2003