• Journal of applied mathematics & informatics
• /
• 제33권1_2호
• /
• pp.211-217
• /
• 2015

A dynamic spectrum access scheme with channel partitioning for secondary handover calls in cognitive radio networks is proposed to reduce forced termination probability due to spectrum handover failure. A continuous-time Markov chain method for evaluating its performance such as blocking probability, forced termination probability, and throughput is presented. Numerical and simulation results are provided to demonstrate the effectiveness of the proposed scheme with channel partitioning.

• 한국시스템다이내믹스연구
• /
• 제5권1호
• /
• pp.127-142
• /
• 2004

Feedback loop dominance is a key concept to understand structural driving forces of system behavior. In this paper, we propose two kinds of shifts in dominant feedback loops: continuous shifts (CS) and discrete shifts (DS). With the help of questionnaires, we verified three hypotheses regarding cognitive biases in perceiving the shifts in dominant feedback loops: 1) failure in perceiving continuous shifts, 2) tendency of decision making based on discrete shifts, and 3) different perception on the dominant feedback loops between level variables and rate variables. We discussed the implication of these cognitive biases on time delay and timing strategy in decision-making processes.

• Safety and Health at Work
• /
• 제9권4호
• /
• pp.434-440
• /
• 2018

Background: In industrial countries, home care of community dwelling elderly people is rapidly growing. Frequent injuries in home caregivers result from slips, trips, and falls (STFs). The current study tests attentional cognitive failure to mediate the association between work stressors and STFs. Methods: A sample of 125 home caregivers participated in a questionnaire study and reported work interruptions, unreasonable tasks, quality-threatening time pressure, conscientiousness, attentional cognitive failures, and STFs. Results: In structural equation modeling, the mediation model was shown to fit empirical data. Indirect paths with attentional cognitive failures as the link between work stressors and STF were all significant in bootstrapping tests. An alternative accident-prone person model, that suggests individual differences in conscientiousness to predict attentional cognitive failures that predict more frequent work stressors and STFs, showed no significant paths between work conditions and STFs. Conclusion: To prevent occupational injury, work should be redesigned to reduce work interruptions, unreasonable tasks, and quality-threatening time pressure in home care.

• Safety and Health at Work
• /
• 제5권1호
• /
• pp.1-6
• /
• 2014

Background: Workflow interruptions during surgery may cause a threat to patient's safety. Workflow interruptions were tested to predict failure in action regulation that in turn predicts near-accidents in surgery and related health care. Methods: One-hundred-and-thirty-three theater nurses and physicians from eight Swiss hospitals participated in a cross-sectional questionnaire survey. The study participation rate was 43%. Results: Structural equation modeling confirmed an indirect path from workflow interruptions through cognitive failure in action regulation on near-accidents (p < 0.05). The indirect path was stronger for workflow interruptions by malfunctions and task organizational blockages compared with workflow interruptions that were caused by persons. The indirect path remained meaningful when individual differences in conscientiousness and compliance with safety regulations were controlled. Conclusion: Task interruptions caused by malfunction and organizational constraints are likely to trigger errors in surgery. Work redesign is recommended to reduce workflow interruptions by malfunction and regulatory constraints.

• 한국과학교육학회지
• /
• 제29권4호
• /
• pp.414-422
• /
• 2009

본 연구에서는 학습자의 동기적 특성이 불일치 사례를 이용한 밀도 개념 학습 과정에 미지는 영향을 조사하였다. 두 개의 중학교 1학년 학생 642명이 연구에 참여하였으며, 사전 검사로 실패에 대한 인내, 자아효능감, 과제 목표 지향과 수행 목표 지향 검사를 실시한 뒤, 선개념 검사를 실시하였다. 개념 변화 학습의 주요 단계를 포함한 학습지를 이용하여 밀도 학습에 대한 개별적인 학습을 실시한 뒤, 사후 검사로 주의집중, 노력, 개념 이해도 검사를 실시하였다. 목표 오개념을 지닌 203명의 학생들의 응답을 경로 분석한 결과, 동기적 특성 변인들은 인지 갈등에 영향을 주지 않았다. 그러나 실패에 대한 인내와 과제 목표 지향은 상황 흥미와 주의집중, 노력을 매개로 개념 이해도에 영향을 주었다. 자아효능감은 노력을 매개로 개념 이해도에 영향을 주었다. 수행 목표 지향은 주의집중과 노력을 매개로 개념 이해도에 부적인 영향을 주었다. 인지 갈등은 상황 흥미를 매개로 간접적으로뿐 아니라 직접적으로도 개념 이해도에 영향을 주었다.

• 디지털융복합연구
• /
• 제16권9호
• /
• pp.405-412
• /
• 2018

영화 흥행의 예측이 필요한 시점은 영화 제작 전에 시나리오에 대한 투자를 결정하는 시점이다. 이런 요구에 따라 최근 인공지능 기반 시나리오 분석 서비스가 출시되었으나, 아직 그 알고리즘이 완벽하지는 않다. 본 연구의 목적은 인간의 뇌 작동 기작에 기반 하여, 영화 시나리오 흥행 예측 모형을 제시하는 것이다. 이를 위해 베버의 자극 반응 법칙과 뇌의 자극 기작 이론 등을 적용하여, 디즈니 애니메이션 흥행작의 시각, 청각, 인지적 자극의 타임 스펙트럼 패턴 도출을 시도한 결과는 다음과 같다. 첫째, 흥행작에서 나타난 뇌 자극의 빈도가 비 흥행작보다 약 1.79배가 많았다. 둘째로, 흥행작에서는 지각 자극 코드들이 타임 스펙트럼 상에 고른 분포를 보인 반면에 비흥행작에서는 집중 분포를 보였다. 셋째로, 흥행작에서는 인지적 부담이 큰 인지적 자극은 주로 단독적으로 등장한 반면에, 인지적 부담이 적은 시각적, 청각적 자극은 두 가지가 동시에 등장하였다.

• 아동학회지
• /
• 제8권1호
• /
• pp.65-82
• /
• 1987

The purpose of the present research was to study mothers' perceptions about their children' cognitive abilities and the relations between such perceptions and the children's cognitive level. The subjects of this study were 60 children (mean age: 6 years 1 month: age range = 5;8 to 6;7) and their mothers. Each child responded to 18 tasks drawn from the Kodae-Binet IQ test. Subsequently, the mothers were asked 4 questions: an estimate of her child's success or failure on the tasks, a rating of the certainty of her judgment, an estimate of the age of mastery on each task both for her owr child and children in general. The data of the present study were analyzed with the 3-way ANOVA (sex x birth order x mother's education level), t-test, and Pearson correlation coefficient. Significant differences were found in (1) mothers' accuracy of their children's cognitive abilities according to children's birth order, (2) mothers' accuracy, overestimation, and certainty according to the level of difficulty of each task, and (3) mothers' estimate of age at mastery according to the level of each task. Furthermore, there were positive correlations between accurate predictions by the mother and correct answers by the child and between overestimations by the mother and correct answers by the child.

• 한국건설관리학회논문집
• /
• 제18권2호
• /
• pp.38-48
• /
• 2017

건설재해의 직접적인 원인은 작업자의 불안전한 행동과 작업장의 불안전한 상태로 분류할 수 있다. 그러나 작업자의 불안전한 행동의 원인은 불안전한 상태에 비해 상대적으로 발견이 어렵다. 왜냐하면 불안전한 행동은 개인의 인지과정을 거쳐 순식간에 발생하기 때문이다. 따라서 작업자 인지과정모델을 통해 불안전한 행동의 원인을 밝히고 그 관리방안을 밝히는 것이 본 연구의 목적이다. 작업자의 인지과정모델을 개발하기 위해 피드백 관계를 규명하기에 알맞은 시스템 다이내믹스 방법론을 사용하였다. 개발된 인지과정모델은 작업자가 위험을 인식하지 못하는 그 상황 자체의 위험성에 대하여 강조하였으며 작업자가 위험을 인식 하였더라도 불안전한 행동을 할 수 있음을 나타냈다. 또한 불안전한 행동이 바로 사고로 이어지지 않는다는 습관은 작업자의 안전에 대한 부정적 태도인 태도로 이어진다는 점에 대해서도 규명하였다. 이러한 분석은 건설현장의 안전관리자가 작업자의 인지상태를 관리하는데 도움이 될 것이다.

• 산업경영시스템학회지
• /
• 제17권32호
• /
• pp.243-253
• /
• 1994

Work environments have been changed with the advent of new technologies, such as computer technology. The newer technologies, the more changes in our work conditions. However, human cognitive limits can't keep up with the change of work environments. Mental workload has been an important factors in designing modem work environments such as human-computer interaction. Designing man-machine systems requires knowledge and evaluation of the human cognitive processes which control information flow workload. Futhermore, under an urgent situation, human operator may suffer the work stress, work error, and resultant deleterious work performance. To describe the work performance in the urgent work situations, with time stress and dynamic event occurence, a new concept of information density was introduced. For a series of experiments performed for this study, three independent variables(information amount system processing time, information density) were evaluated using such dependent variables as reaction time, number of error, and number of failure. The results of statistical anlysiss indicate that the amount of information effected on all of five dependent measure. Number of failure and number of secondary task score were effected by both amount of information and operational speed of system, but reaction time of secondary task were effected by both amount of information and information density.

• 한국정보시스템학회지:정보시스템연구
• /
• 제1권
• /
• pp.95-109
• /
• 1992

A number of success story about various application areas including manufacturing, accounting, finance, education, and engineering are reported. MIS professionals predicted that expert systems would improve the productivity enormously. However, the expert system revolution has not happened yet. Although not reported in the open society widely, there are failure stories of expert systems. Most of problems concerning expert system failure stem from the non-technical issues such as cognitive and psychological problems rather than the technical issues. We hypothesize that human factor principle enables designers to handle most of these non-technical problems elegantly and to improve the performance and acceptance of the expert systems. Major reasons for expert system failure and needs of human factors are discussed. Human factor guidelines to expert system make the prospects of the expert systems with human factors clear and understandable.