• 예술인문사회 융합 멀티미디어 논문지
• /
• 제7권1호
• /
• pp.253-263
• /
• 2017

최근 한국사에 필요성이 증대하고 사람들의 관심이 높아지면서, 한국사 학습을 위한 다양한 어플리케이션들이 등장하고 있다. 이러한 기존의 한국사 학습 어플리케이션은 문제은행 방식으로 사용자들에게 객관식 문제를 제공한다. 하지만 문제은행 방식은 미리 저장된 문제를 가져와 사용함으로써 계속 사용할 경우 중복되는 문제로 인하여 필연적으로 학습효율이 떨어지게 된다. 본 논문에서는 한국사 데이터베이스를 기반으로 한국사 학습문제를 자동적으로 생성하는 시스템인 K-History의 개발과 이를 활용한 한국사 학습 어플리케이션인 한국사 무한도전의 개발에 대하여 기술한다. K-History의 개발을 위하여 한국사 학습 교재를 바탕으로 다양한 한국사 학습 문제를 분석하여 학습문제의 대표 유형을 분류하고, 발견된 유형에 따라 문제를 생성하는 알고리즘을 제안한다. 개발된 한국사 학습문제 생성 기법은 다양한 학습 시스템에 적용되어 문제 생성을 위한 비용을 줄일 수 있으며, 다양하게 생성된 학습문제를 통하여 학습자의 학습효율을 높일 수 있을 것으로 기대된다.

• 한국시뮬레이션학회논문지
• /
• 제3권2호
• /
• pp.57-67
• /
• 1994

For many practical and industrial optimization problems where some or all of the system components are stochastic, the objective functions cannot be represented analytically. Therefore, modeling by computer simulation is one of the most effective means of studying such complex systems. In this paper, with discussion of simulation optimization techniques, a case study in machining process for application of simulation optimization is presented. Most of optimization techniques can be classified as single-or multiple-response techniques. The optimization of single-response category, these strategies are gradient based search methods, stochastic approximate method, response surface method, and heuristic search methods. In the multiple-response category, there are basically five distinct strategies for treating the responses and finding the optimum solution. These strategies are graphical method, direct search method, constrained optimization, unconstrained optimization, and goal programming methods. The choice of the procedure to employ in simulation optimization depends on the analyst and the problem to be solved.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제12권8호
• /
• pp.3704-3724
• /
• 2018

This paper proposes an advanced turbo receiver with joint inter-carrier interference (ICI) self cancellation and channel equalization for multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems over rapidly time-varying channel environment. The ICI caused by impairment of local oscillators and carrier frequency offset (CFO) is the major problem for MIMO-OFDM communication systems. The existing schemes (conjugate cancellation (CC) and phase rotated conjugate cancellation (PRCC)) that deal with the ICI cancellation and channel equalization can't provide satisfactory performance over time-varying channels. In term of error rate performance and low computational complexity, ICI self cancellation is the best choice. So, this paper proposes a turbo receiver to deal with the problem of joint ICI self cancellation and channel equalization. We employ the adaptive phase rotations in the receiver to effectively track the CFO variations without feeding back the CFO estimate to the transmitter as required in traditional existing scheme. We also give some simulations to verify the proposed scheme. The proposed schene outperforms the existing schemes.

• 한국산업정보학회논문지
• /
• 제11권3호
• /
• pp.69-81
• /
• 2006

In this paper, an adaptive algorithm is proposed in streaming MPEG-4 contents with fluctuating resource amount such as throughput of network conditions. In the area of adaptive streaming issue, a lot of researches have been made on how to represent encoded media(such as video) bitstream in scalable way. By contrast, MPEG-4 supports object-based multimedia content which is composed of various types of media streams such as audio, video, image and other graphical elements. Thus, it can be more effective to provide individual media streams in scalable way for streaming object-based content to heterogeneous environment. The proposed method provides the multiple media streams corresponding to an object with different qualities and bit rate in order to support object based scalability to the MPEG-4 content. In addition, an optimal selection of the multiple streams for each object to meet a given constraint is proposed. The selection process is adopted a multiple choice knapsack problem with multi-step selection for the MPEG-4 objects with different scalability levels. The proposed algorithm enforces the optimal selection process to maintain the perceptual qualities of more important objects at the best effort. The experimental results show that the set of selected media stream for presenting objects meets a current transmission condition with more high perceptual quality.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국제학술편); Seoul National University, Seoul; 20-22 Oct. 1993
• /
• pp.486-490
• /
• 1993

In addtion to a basic motion task, redundant manipulators can achieve some additional tasks by optimizing proper performance criteria. Some of performance criteria can be transformed to inequality constraints. So the redundancy resolving problem can be reformulated as a local optimization problem with equality constraints for the end effector and inequality constraints for some performance criteria. In this article, we propose a method for solving the inverse kinematics of a manipulator with redundancy using the Kuhn-Tucker theorem to incorporate inequality constraints. With proper choice of inequality constraints, the proposed method gives a way of optimizing multiple criteria in redundant manipulators.

• 한국과학교육학회지
• /
• 제15권4호
• /
• pp.437-451
• /
• 1995

Middle and high school students' conceptual understanding about stoichiometry, gas laws, and diffusion was compared with essay type test and multiple choice test. Whereas achievement of high school students was higher in stoichiometry, that of middle school students who were expected to go to high schools was higher in gas laws and diffusion. When students' achievement was compared to that of American college students, Korean students' achievement was higher in stoichiometry and was similar in gas laws. These results indicate that algorithmic problem solving is more emphasized than conceptual understanding in high schools and that quantitative aspects focused in chemistry education are not helpful in concept understanding. Nevertheless relatively smaller difference between concept understanding and algorithmic problem solving for high school students in this study seems to be from concept learning in middle schools.

• 영어어문교육
• /
• 제1호
• /
• pp.69-108
• /
• 1995

Listening comprehension can be defined as a process of an integrative, positive and creative activity through which listeners get the message of speakers' production using linguistic or non-linguistic redundancy as well as linguistic or non-linguistic knowledge. Compared with reading comprehension, it has many difficulties especially for foreigners. while it can be transferred to the other skills: speaking, reading, writing. With this said, listening comprehension can be taught effectively using the following teaching strategies. First. systematic and intensive instruction of segmental phonemes, suprasegmental phonemes and sound changes must be given to remove the difficulties of listening comprehension concerned with the identification of sounds. Second, vocabulary drill through various games and other activities is absolutely needed until words can be unconsciously recognized. Without this, comprehension is almost impossible. Third, instruction of sentence structures is thought to be essential considering grammar is supplementary to listening comprehension and reading comprehension for academic purpose. So grammar translation drills, mechanical drills, meaningful drills and communicative drills should be performed in succession with common or frequently used structures. Fourth, listening activities for overall comprehension should teach how to receive overall meaning of intended messages intact. Linguists and literatures have listed some specific activities as follows: Total Physical Response, dictation, role playing, singing songs, selective listening, picture recognition, list activities, completion, prediction, true or false choice, multiple choice, seeking of specific information, summarizing, problem-solving and decision-making, recognization of relationships between speakers, recognition of mood, attitude and behavior of speakers.

• 치위생과학회지
• /
• 제23권4호
• /
• pp.271-281
• /
• 2023

Background: This study aims to improve dental hygiene education by investigating the relationship between metacognition, learning flow, and problem-solving abilities in dental hygiene majors. Methods: A survey was conducted on 2nd to 4th-year students from dental hygiene programs, with 132 responses analyzed. Data analysis involved t-tests and ANOVA to examine the differences in metacognition, learning flow, and problem-solving abilities based on the general characteristics. Multiple regression analysis was employed to investigate the factors influencing the dependent variable, which is problem-solving abilities. The collected data were analyzed using SPSS. Results: First, when comparing metacognition, learning flow, and problem-solving abilities based on the general characteristics of the study participants, statistically significant differences were observed in common factors such as major satisfaction, subjective academic performance, GPA (grade point average), and reason for major choice (p<0.05). Second, it was found that there is a significant positive correlation between metacognition, learning flow, and problem-solving abilities in dental hygiene students (r≥0.79, p<0.05). In other words, higher levels of metacognition and learning flow were associated with better problem-solving abilities. Third, factors influencing problem-solving abilities were identified, with both metacognition and learning flow having a statistically significant positive impact. It was also noted that metacognition had a greater influence on problem-solving abilities compared to learning flow (adjusted R²=0.815, p<0.05). Conclusion: To enhance the core competency of problem-solving abilities, it is essential to improve metacognition and learning flow. To enhance metacognition and promote learning flow, strategies such as goal setting, utilizing effective learning methods, boosting self-efficacy, managing the learning environment, choosing activities that foster immersion, stress management, self-assessment and feedback integration, improving focus, and utilization a variety of learning experiences will be necessary.

• 한국정보시스템학회지:정보시스템연구
• /
• 제14권1호
• /
• pp.19-40
• /
• 2005

The history of computer virus comes along with that of computer. Computer virus han surfaced as a serious problem in information age. The advent of open network and widespread use of Internet made the problem even more urgent. As a method of defense for computer virus most companies use anti-virus software. Selecting appropriate anti-virus software involves various criteria and thus it is a multiple-attribute decision making problem. The purpose of this study is to prioritize anti-virus software evaluation factors. To do that, first of all, important evaluation factors are selected based on previous research on anti-virus software as well as general software evaluation models. Then, a questionnaire survey was conducted on end-users, system administrators and anti-virus software developers. The survey result was analyzed with ExpertChoice 2000 which is based on Analytic hierarchy Process technique. This study found that there are clear differences among three survey groups regarding the relative importance of overall evaluation factors. End-user group ranked "cost" first, but it was the least important factor to developer group. Developers pointed out "operational support" ad the most important factor. There were also obvious differences in the relative importance of detail evaluation items. Both end-users and system administrators shared 7 common items among top 10 most important items. Moreover, neither of the two groups ranked any of the items in the "operational support" factor in top 10, whereas all 4 items in the factor were included in top 10 by developer group.

• 한국과학교육학회지
• /
• 제21권2호
• /
• pp.289-298
• /
• 2001

분자 수준의 그림과 4단계 문제 해결 전략을 제시한 후 해결자 청취자 활동을 통해 문제 해결 과정을 점검하도록 한 교수 방법의 효과를 조사하였다. 고등학교 4학급(191명)을 선정하여 개별적으로 전략을 사용하는 집단(St; Strategy), 해결자 청취자 활동을 하는 집단(SL; Solver' Listener), 전략을 사용하며 해결자 청취자 활동을 하는 집단 (St-SL; Strategy-Solver' Listener), 그리고 통제 집단으로 무선 배치하였다. 전략 수행 능력 검사에서 St-SL 집단의 점수가 통제 집단에 비하여 유의미하게 높았으나, 객관식 문제 해결력 검사에서는 유의미한 차이가 나타나지 않았다. 전략 수행 능력 검사의 하위 범주들에서는 문제의 조건을 파악하거나 올바른 물리량을 유도해내는 능력은 향상된 데에 비하여, 하위 목표를 설정하거나 해결 과정을 검토하는 능력은 매우 낮은 것으로 나타났다. 전략에 대한 선호도는 St 집단보다 St-SL 집단에서 보다 긍정적인 것으로 조사되었다.