• 디지털산업정보학회논문지
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• 제10권4호
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• pp.97-107
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• 2014

The development of ICT has led positive aspects such as popularization of Internet. It, on the other hand, is causing a negative aspect, Cyber Terror. Although the causes for recent and continuous increase of cyber security incidents are various such as lack of technical and institutional security measure, the main cause which threatens the cyber security is the users' lack of awareness and attitude. The purpose of this study is the positive analysis of how the personal and job characteristics influence the cyber security training participation rate and the response ability to cyber terror response training with a sample case of K-corporation employees. In this paper, the relationship among career, gender, department, whether he/she is a cyber security specialist, whether he/she is a regular employee), "ratio of cyber security training courses during recent three years", "ratio that he/she has opened the malicious email in cyber terror response training during recent three years", "response index of virus active-x installation (higher index means poorer response)" is closely examined. Moreover, based on the examination result, the practical and political implications regarding K-corporation's cyber security courses and cyber terror response training are studied.

• Nuclear Engineering and Technology
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• 제53권12호
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• pp.4033-4041
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• 2021

To better understand the permeability of uranium sandstone, improve the leaching rate of uranium, and explore the change law of pore structure characteristics and blocking mechanism during leaching, we systematically analyzed the microstructure of acid-leaching uranium sandstone. We investigated the variable rules of pore structure characteristics based on nuclear magnetic resonance (NMR). The results showed the following: (1) The uranium concentration change followed the exponential law during uranium deposits acid leaching. After 24 h, the uranium leaching rate reached 50%. The uranium leaching slowed gradually over the next 4 days. (2) Combined with the regularity of porosity variation, Stages I and II included chemical plugging controlled by surface reaction. Stage I was the major completion phase of uranium displacement with saturation precipitation of calcium sulfate. Stage II mainly precipitated iron (III) oxide-hydroxide and aluminum hydroxide. Stage III involved physical clogging controlled by diffusion. (3) In the three stages of leaching, the permeability of the leaching solution changed with the pore structure, which first decreased, then increased, and then decreased.

• 공학교육연구
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• 제26권6호
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• pp.51-61
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• 2023

In this study, the effects of pre-learning attitude on learning participation and academic achievement was analyzed when applying the flipped learning methodology to engineering subject education. The modified PARTN teaching and learning model was applied, and pre-class survey, assessment on learning in pre-class, and post-class survey were conducted to analyze the effectiveness of flipped learning. The results were analyzed for 24 students who took the applied thermodynamics lecture. They were asked to take the course with the videos provided in the pre-class stage, and a pre-learning assessment was conducted to measure the completeness and understanding of the learning. As a result of the study, it was found that students with relatively excellent learning ability had excellent pre-learning evaluation results and excellent final academic achievement. In addition, the lower the pre-learning completion rate within the pre-learning period or the higher the learning rate using mobile devices, the more difficult it was to faithfully complete pre-learning, leading to poor pre-learning evaluation results. Meanwhile, the survey revealed that conducting pre-learning assessments were helpful in encouraging individual learning. In addition, cases reflecting pre-learning evaluation results to course grades showed higher pre-learning evaluation results than cases not reflecting pre-learning evaluation results to course grades, and in flipped learning classes, pre-learning evaluations act as a factor that promotes pre-class learning.

• 인지과학
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• 제17권2호
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• pp.139-150
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• 2006

음성 대화 시스템에서 음성 인식 오류는 전체 시스템의 치명적인 결과를 초래한다. 음성 인식 오류가 부분적으로 발생하여 화행 분석이 실패했을 때 시스템은 원활한 대화를 진행할 수 없다. 본 논문은 양식 채우기 대화 형식에서 발생하는 음성 인식 오류 유형에 따라 시스템이 사용자 발화의 화행을 추론하기 위한 부대화 생성 전략을 제안한다. 제안하는 방법을 계획기반 대화 모델로 구현하여 실험하였고, 사용자 작업 실패 오류의 약27%를 보완하여 성능을 향상시켰으며 전체 시스템의 사용자 작업 성공률은 약 89%이다.

• Journal of applied mathematics & informatics
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• 제8권1호
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• pp.199-212
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• 2001

We consider a k-out-of-n system with repair under T-policy. Life time of each component is exponentially distributed with parameter $\lambda$. Server is called to the system after the elapse of T time units since his departure after completion of repair of all failed units in the previous cycle or until accumulation of n-k failed units, whichever occurs first. Service time is assumed to be exponential with rate ${\mu}$. T is also exponentially distributed with parameter ${\alpha}$. System state probabilities in finite time and long run are derived for (i) cold (ii) warm (iii) hot systems. Several characteristics of these systems are obtained. A control problem is also investigated and numerical illustrations are provided. It is proved that the expected profit to the system is concave in ${\alpha}$ and hence global maximum exists.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.700-705
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• 2007

In this study, we observe the application of shape memory alloy(SMA) into smart structures for repeatable actuation, because SMA changes its material properties and characteristics progressively under cyclic loading conditions and finally reaches stable path(state) after a certain number of stress/temperature loading-unloading cycles, so called 'training'. In this paper, SMA wires that have been in a stable state through the training are used. Stress-strain curve of the SMA wire at different temperature levels are measured. In addition, we observe other important effects such as the rate effect according to strain rates for rapid actuation response. The current work presents the experimental test using SMA wire after training completion by mechanical cycling. Through these tests, we measure the characteristics of SMA. With the estimated SMA properties and effects, we compare the experimental results with the simulation results based on the SMA constitutive equations.

• 수산해양기술연구
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• 제45권4호
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• pp.260-266
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• 2009

In order to obtain the fundamental data for the marine ranch, this paper was carried out to investigate cortisol variation in blood according to adapted time in the measurement of auditory threshold. The groups were adapted at the experimental tanks for 0.5, 1, 3 and 6 hours, respectively. At the results, cortisol concentration had a deep connection with adapted time. In particular, cortisol concentration in the experimental group of 1 hour was significantly increased, whereas others showed no difference comparing with the control group. When classical conditioning method with the sound coupled with a delayed electric shock was given after the adapted time of 1 hour and 6 hours, the rate of the conditioning completion for 6 hours was higher than that of 1 hour. Therefore, this suggests that the sufficient adapted time was required for the accurate auditory threshold.

• 공업화학
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• 제9권2호
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• pp.300-305
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• 1998

세 종류의 모노머로 구성된 삼모노머중합의 동력학을 입자성장이 끝난 interval II 동안 pseudo-homopolymerization (PHP) 방법에 의하여 연구하였다. 삼모노머중합의 Smith-Ewart 확장식과 순간중합조성식을 단일유화중합의 해당식과 유사하게 나타낼 수 있었다. 입자당 평균라디칼수와 순간중합조성을 라텍스입자내의 모노머조성을 변화시킴으로써 입자당 자유라디칼수가 한 개 이하인 계에서 예측하였다. 모델계산의 예로서 Styrene-Methyl methacrylate-Acrylonitrile(SMA)계의 속도상수들을 사용하였다.

• International Journal of Contents
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• 제6권4호
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• pp.101-107
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• 2010

I aim to discover that how greatly the curriculum of Life Dance department has had an effect on the career of students majoring in dance, with research objects being Life Dance department of two universities, located on the metropolitan area. The study method, called qualitative, includes some suggestions on the curriculum of the two and comparison, analysis of job-related materials; further, it involves discussion on the influence the curriculum has had on the career as dance trainers. The results from it are as follows; first, the curriculum of the department mostly consists of pure art such as Korean dance, modern dance, ballet, but has few creative life dance programs. Second, the employment into the art area has been more often than to the counterpart. Finally, it shows that a title of a department does not make a big difference and affect the employment rate. In conclusion, as the completion of the curriculum does not always guarantee a success, it is recommended that college students get some competent certificates related to dance.

• International Journal of Air-Conditioning and Refrigeration
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• 제7권
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• pp.101-111
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• 1999

The effect of various conditions of frosting and defrosting on the defrosting behavior of a fin-tube heat exchanger has been examined experimentally. An electric heater is used for defrosting in a fin-tube heat exchanger. There are several local maxima in the water draining rate. The amount of residual water on the heat exchanger after completion of defrosting is kept constant due to surface tension on the heat exchanger. Without considering degradation of the thermal performance due to the frosting, the defrosting efficiency is improved with increasing amount of frost irrespective of the frosting condition. The defrosting behavior is affected by frosting density as well as frost accumulation, both of which vary with the experimental operating conditions. The heat loss to the surrounding air decreases, and melting and defrosting efficiencies show high values with decreasing heat input.