• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2002년도 추계학술대회 논문집
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• pp.114-119
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• 2002

In driving situation, driver’s performance can be divided into primary task and secondary task. Many studies of primary task have been in progress, but those of secondary task are not implemented sufficiently. However, the driver’s error is greatly influenced by secondary task. In this study, an experiment was assessed to determine the relationship between the driver's operation time for the secondary task and mental workload due to speed changes in a driving simulation. The time to perform the secondary task was analyzed with Fitts’ Law, and mental workload was analyzed with RNASA-TLX(Revision of NASA-Task Load Index). The results has showed that the higher speed, the weaker the explanation by the use of Fitts' Law and the result of analyzing mental workload using RNASA-TLX was similar to the result of Fitts’ Law.

• 산업경영시스템학회지
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• 제21권45호
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• pp.145-154
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• 1998

The effects of secondary task on driving performance and subjective workload were investigated during a simulated driving. The driving performance was determined by the appropriateness of break timing. The driving simulator was provided by the Korea Road Traffic Safety Association. The subjective workload was tested by using a multidimensional measure such as NASA-TLX. Road was categorized into two types: narrow alley and wide street. The secondary task included pushing the number on the cellular phone, pushing radio channel, and conversing with a passenger. Seventeen subjects volunteered in the study. The data were analyzed by using SAS. Results showed that using the cellular phone and pushing channel during driving caused 3∼22% decline of driving performance and 42∼59% increase of subjective workload respectively. These results indicated that the secondary task could be potentially dangerous although there was not a significant performance decrease due to the notable increase of mental workload. In the future, if we can use a more sensitive and realistic driving simulator, the effects of secondary task under a dynamic driving situation can be investigated.

• 대한산업공학회지
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• 제40권3호
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• pp.267-274
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• 2014

The purpose of this study is to identify a relationship between the time taken and the characteristics of touch key for touch-screen-based in-vehicle information system (IVIS) and to suggest a new Fitts' law formula that is added a driving speed parameter. Many studies already have shown that Fitts' law is well fitted in various devices for primary tasks, but there is no study of Fitts' law for secondary task in dual-task situation. Fitts' law may not be applied to the secondary task as it is, because the secondary task performance can be affected by the amount of attention for the primary task. To verify this, we carried out an experiment that showed whether pointing task to touch-screen-based IVIS during driving is affected by driving speeds or not. In the experiment, 30 people were volunteered for participants and the participants carried out driving task and pointing task on the screen of IVIS simultaneously. We measured the time to point a touch key on IVIS for every condition (3 driving speeds${\times}5$ touch key sizes${\times}7$ distances between steering wheel and touch key). As a result, there was an effect of driving speed on the pointing time. As we extended the index of difficulty of the conventional Fitts' law formula by incorporating driving speed, we established an extended Fitts' law formula for pointing on IVIS, which showed better accordance with dual task situation. This study can be evidence that secondary task performance is affected by degree of concentration on primary task, and the extended Fitts' law formula can be useful to design interfaces of IVIS.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2008년도 추계학술대회 논문집
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• pp.179-180
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• 2008

• 한국과학교육학회지
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• 제16권4호
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• pp.477-485
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• 1996

The purpose of this study was to identify the preferable motivation types in science-learning and to find out the relationship between these types and scientific achievement of students in the secondary school. The subjects of the study were the second grade 581 students sampled by random cluster sampling method in three middle schools and three high schools. Three motivation types in science learning were analyzed, and they were named to task-orientation, ego-orientation and work-avoidance. From our results, secondary school students preferred task-orientation and work-avoidance to ego-orientation. In the case of task-orientation, high school students, especially in male group, had much preferable tendency than that of middle school students (p<0.001). It is interpreted that, as the level of scientific content of texts or the cognitive level of students were higher, a preference for the motivation type was focused to the task-orientation, especially in male group. In the case of ego-orientation, the female group showed much preferable tendency than that of male group in middle school (p<0.05). However, the female group in high school students was not different from the other groups in this motivation type. In the case of work-avoidance, there were not only a significant difference between males and females in the middle school (p<0.001), but also difference between middle and high school students in female group (p<0.05). It showed that female group had much preferable tendency than that of male group, and this tendency was decreased to the higher grade students in secondary school. From the analysis of correlation between motivation types and scientific achievement, task-orientation and work-avoidance were correlated to the scientific achievement. Its results were interpreted that the scientific achievement could be accomplished by the external motivation stimulus as well as the scientific content of texts. The task-orientation were comparatively correlated to the intelligence quality. It means that the students having high intelligence quality showed much preferable for the task-orientation.

• 대한인간공학회지
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• 제32권2호
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• pp.189-198
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• 2013

Objective: This research was carried out to study the menu type design of instrument cluster IVIS(In Vehicle Information System) for efficient navigation under deconcentrated situations. Background: A driver controls the IVIS menu using the rest of cognitive resources while driving a car. Although a driver controls the IVIS using extra cognition resources, his or her distraction can still cause some safety problems while driving. Menu type design of instrument cluster is absolutely important for safe and efficient navigation. Method: Four menu types including paging, flow, icon, and list type were identified through reviewing the existing IVIS of vehicle and the menu structure of cellular phone. Four menu types were evaluated through experiment. The experiment consisted of primary and secondary task, which the primary task was to simulate a driving and the secondary task was to control an IVIS menu prototype. Task performances, menu type preferences, and eye-movement patterns were measured in this experiment. Results: The result shows that icon type was the best design in aspect of task performance and preference. A clue for next menu item provided a positive effect for efficient menu navigation. It was identified that most of subjects gazed the middle-top area of IVIS screen from eye-movement pattern. Conclusion: A basic design of Instrument Cluster IVIS was proposed considering the result of this study in the final. Application: The results of this study can be effectively used in the design of Instrument Cluster IVIS.

• The Journal of Korean Physical Therapy
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• 제27권5호
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• pp.292-298
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• 2015

Purpose: The purpose of this study was to examine the effects of dual tasks on balance and postural control during standing in patients with cerebellar ataxia (CA). It was hypothesized that CA patients would exhibit different sway characteristics of the center of mass (COM) depending on the complexity of the secondary cognitive tasks compared with normal control subjects. Methods: A total of 8 patients with CA and age-matched healthy control subjects participated in this study. They were instructed to perform two balance tasks (non-dual and dual movement) with 3 different complexity of dual tasks. Range, variability, and velocity of COMs were measured. Results: According to the results CA patients showed deficits in balance and postural control with increased dual-task complexity during the static balance task in saggital sway movements. However, there was no significant difference in static balance in frontal sway. With higher difficulty in the cognitive task, CA patients took longer to stabilize their body center, while normal control subjects showed no change between conditions. In addition, CA patients had a greater COM resultant velocity during recovery in the dual-task condition compared with the single-task condition. These findings indicate that CA patients had defendable compensatory strategies in performing dual tasks. Conclusion: In conclusion, CA patients appeared to manage the priority to balance and postural control. Particularly in a situation with a postural threat such as when potential consequences of the loss of stability increase, they appeared to prioritize the control of balance and posture over the performance of the secondary task.

• 대한인간공학회지
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• 제31권2호
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• pp.371-377
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• 2012

Objective: The aim of this study is to investigate effect of driver's cognitive distraction on driver's physiological state and driving performance, and then to determine parameters appropriate for detecting the cognitive distraction. Background: Driver distraction is a major cause of traffic accidents and poses a serious threat to traffic safety due to ever increasing use of in-vehicle information systems and mobile phones during driving. Cognitive distraction, among four different types of distractions, prevents a driver from processing traffic information correctly and adapting to change in surround vehicle behavior in time. However, the cognitive distraction is more difficult to detect because it normally does not involve significant change in driver behavior. Method: A full-scale driving simulator was used to create virtual driving environment and situations. Participants in the experiment drove the driving simulator in three different conditions: attentive driving with no secondary task, driving and conducting secondary task of adding numbers, and driving and conducting secondary task of conversing with an experimenter. Parameters related with driver's physiological state and driving performance were measured and analyzed for their change. Results: The experiment results show that driver's cognitive distraction, induced by secondary task of addition and conversation during driving, increased driver's cognitive workload, and indeed brought change in driver's physiological state and degraded driving performance. Conclusion: The galvanic skin response, pupil size, steering reversal rate, and driver reaction time are shown to be statistically significant for detecting cognitive distraction. The appropriate combination of these parameters will be used to detect the cognitive distraction and estimate risk of traffic accidents in real-time for a driver distraction warning system.

• 한국산업정보학회논문지
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• 제10권2호
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• pp.21-25
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• 2005

본 연구는 인간의 정신부하작업중 반응시간이 제한된 긴급상황에서 시스템이 비정상적인 상태로 변화할 경우 인간의 수행도 특성을 살펴보고 이를 보조할 수 있는 보조장치의 설계에 도움을 주는 기준 안을 제시하고자 한다. 긴급상황에서 최우선시 되는 수행도는 반응시간보다는 시스템을 성공적으로 제어하여 비극적인 재해를 방지하는 일이다. 그러므로 여러 작업 수행도들 중에서 제어에 실패하게 되는 요인의 영향도를 알아내는 것이 중요하다. 실험결과 인간의 반응은 극히 제한된 짧은 반응시간내의 단일작업에서의 수행도는 시스템의 전체 영향도를 제대로 반영하지 못함을 알 수 있었다. 이럴 경우 부수작업을 부여했을 때 시스템의 변화 요인의 영향도를 더욱 잘 나타내는 것임을 유도하였다. 그러므로 시스템의 상황이 비 정상적인 상태로 진행될 경우, 특히 이러한 상황에서 반응해야 할 시간이 제한적일 경우 수행도 측정에는 다양한 형태의 부수작업을 개발하고 이를 이용한 측정이 더욱 효율이 있다는 점을 제시한다. 이러한 실험의 결과를 유추해보면 안전장치 기기의 설계를 위해서는 운용되는 상황에 맞는 측정방법이 개발되어야 긴급 상황의 수행도를 측정할 수 있다.

• 한국수학교육학회지시리즈A:수학교육
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• 제60권1호
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• pp.61-76
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• 2021

본 연구는 수학 예비교사들이 과제의 인지적 노력 수준 변형에서 겪는 오류와 어려움을 분석하여, 수학 과제 변형과 관련한 수학 예비교사 교육에 유의미한 시사점을 제공하는 것을 목적으로 한다. 이를 위해 24명의 수학 예비교사들을 대상으로 수직이등분선의 성질에 대한 추론 과제를 높은 수준과 낮은 수준으로 변형하는 활동과 이에 대한 반성 및 수정 기회를 제공하였다. 변형 과제를 중심으로 예비교사들이 과제의 수준 변형에서 겪는 오류와 어려움을 분석한 결과, 과제 수준의 판단 관점에서 PNC와 PWC 과제의 구분에 제한된 이해를 보였으며, 과제의 외형적인 요소에 의존하는 간섭 현상을 확인하였다. 과제 수준의 변형 관점에서 예비교사들은 과제의 목표와 수직적 위계를 간과하거나 변형 유형의 편향성을 보였다. 한편 예비교사들은 반성 및 수정 활동을 통해 자신들의 변형 과제의 오류를 인식하고 개선할 수 있었으며, 도구의 범주를 Geogebra를 포함한 공학적 도구로 확장하는 모습을 보여주었다.