• Journal of the Korean Society of Safety
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• v.28 no.1
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• pp.117-124
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• 2013

Emergency operating procedures(EOPs) of nuclear power plants should be described considering the cognitive capability and limitation of operators and provide appropriate information in the aspect of human factors. Procedures which doesn't consider cognitive characteristics of operators can become causes of human errors. In previous researches, in order to reduce these problems related to the description of EOP, an improvement suggestion for EOP writer's guide has been proposed, which is reflected human factors aspects that should be considered when describing EOPs. The proposed items, however, have a necessity to be validated because it was listed from various documents such as standards and guidelines without any special validation process. For that reason, in this study, a validation process were performed to show that procedures, which are described in compliance with the requirement items proposed in the improved EOP writer's guide, have positive effects in the aspects of human errors and performance comparing with previous procedures. Experiments were performed to compare the performances of two tasks which are described in compliance with each writer's guide of before and after the improvement During each task was performed in experiments, changes of physiological responses such as EEG and ECG were measured to evaluate the cognitive workload and the stress of operators in each task. And also, as the performance, frequencies of errors and cognition speeds of each task were evaluated. In the results of the experiment, the portions of the ${\beta}$ wave decreased in the tasks overall after the improvement. In the case of ECG, change rates of the mean of R-R interval were decreased in the tasks after improvement. In the results of the performance, the cognition and the response time of the tasks after the improvement were predominant with statistical significancies. Error times in the tasks after improvement were decreased or same to the tasks before improvement. Conclusively, it was validated that the procedures were described in compliance with the improved EOP writer's guide had effects on the reduction of human errors and improvement of performance.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.12
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• pp.131-137
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• 2009

Recent technological advances made a vehicle more intelligent to increase safety and comfort. An intelligent vehicle provides drivers with safety warning information through audible sounds, visual displays, and tactile devices. However, elderly drivers have been known to decrease the physical and cognitive abilities such as muscular strength, hearing, eyesight, short term memory, and spatial perception. Therefore, possible age-related deficits should be considered to design an effective warning system. This paper aims to evaluate the impact of advancing age on response performance on audible safety warnings which are widely used for alerting driving hazards. In order to understand the effect of age-related hearing loss and movement slowing, three sound characteristics (frequency, intensity, and period) and three age groups (younger, middle, and older) are considered. Data was drawn from 38 drivers who drove a simulated rural road in a driving simulator. Experimental results show that age influences driver's response performance. In conclusion, the appropriate range of a warning sound is suggested.

• Communications for Statistical Applications and Methods
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• v.23 no.6
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• pp.531-541
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• 2016

Cerebral atrophy affects the brain and is a common feature of patients with mild cognitive impairment or Alzheimer's diseases. It is evaluated by the radiologist or reader based on patient's history, age and the space between the brain and the skull as indicated by magnetic resonance (MR) images. A total of 70 patients were scanned in the supine and prone positions before three radiologist assessed their atrophy level. This study examined the radiologist's assessment of the cerebral atrophy level using a graded response model of item response theory (IRT). A graded response model (GRM) is fitted to our data and then item-fit and person-fit statistics are evaluated to assess the fitted model. Our analysis found that the cerebral atrophy level is better discriminated by readers in the prone position because all item slopes were greater than 2 at this position, versus the supine position where all the slope parameters were less than 1. However, the thresholds are very similar for the first reader and are quite different for the second and third readers because the scanning position affects readers differently as the category threshold estimates vary considerably between the readers..

• Korean Journal of Biological Psychiatry
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• v.24 no.4
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• pp.188-195
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• 2017

Objectives Schizophrenia is characterized by disturbances in perception and cognition. Attenuated mismatch negativity (MMN) reflects central auditory dysfunction in schizophrenia. The aim of this study is to compare MMN changes before and after treatment in schizophrenia patients and to assess their association with treatment response. Methods Twenty-three schizophrenia patients underwent an oddball paradigm. MMN was calculated by the difference waveforms of the event-related potentials (ERPs) elicited by subtracting standard from deviant stimulus. The clinical symptoms were measured by the Positive and Negative Syndrome Scale (PANSS), the Psychotic Symptom Rating Scale (PSYRATS). Follow-up evaluation was conducted when the PANSS total score decreased by 30% or more (treatment response group) or before discharge (non-response group). Results The treatment response group showed significantly larger MMN amplitude improvement and latency reduction than the non-response group after treatment (Fz ; mean amplitude p = 0.035, FCz ; p = 0.041). The auditory hallucination group showed shorter latency than that of the group without hallucinations. Additionally, auditory hallucination was associated with prolonged MMN latency and shortened after treatment in the auditory hallucination response group (Fz ; p = 0.048). Conclusions These results suggest that the attenuated MMN amplitude reflects the progression of the disease. The increment of MMN amplitude and shortening of latency after treatment may reflect cognitive functional recovery of central auditory sensory processing.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.494-501
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• 2007

Nowadays, the corporate culture is recognized as an important invisible assets determining the competitive advantages in all the business firms. The purpose of this article is to depict the corporate culture of railroad-related organizations based on the cognitive response of employees. To attain this purpose, several aspects of current corporate cultures are surveyed through questionnaire and analyzed by SPSS. In this paper the theoretical framework adopted was an corporate culture model developed by Rousseau.

• Journal of Korean Academy of Nursing Administration
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• v.8 no.1
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• pp.31-44
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• 2002

The main purpose of this study was to identify the effect of stress management program on the perceived stress, stress response, ways of coping of nurses.The data were collected from September 22 to December 21, 1997. The subjects were 45 emergency nurses of three university hospital located in seoul ; 25 assigned for the experimental group and 20 for the control group.The stress management program was composed of cognitive training, behavioral training and progressive muscle relaxation. The subjects of the experimental group carried out the 15-minute progressive muscle relaxation according to recorded-tape once a day for 6 weeks. The cognitive and the behavioral training were conducted by the investigator for 5～8 subjects at a time for 9 series, at an interval of 4～5days.The instruments used in the study was the perceived stress scale developed by Levenstein et al.(1993), Symptoms of stress Inventory(1991), and ways of coping scale developed by Lazarus & Folkman(1984).The data were analyzed by SAS program, using descriptive statistics, χ2-test, t-test, paired t-test.The results were as follows :1.　The perceived stress of experimental group was lower than that of the control group. However, no significant difference between the two groups was revealed.2.　The stress response of experimental group was reduced after stress management program and the stress response of control group was reduced after stress management program. but no significant difference between the two groups was revealed.3.　The problem oriented coping of the experimental group was higher than that of the control group, however no significant difference between the two groups was revealed.4.　The emotional oriented coping of the experimental group was lower than that of the control group, however no significant difference between the two groups was revealed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.185-191
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• 2018

This study examined the type and extent of interruption between induced emotion and succeeding arithmetic operation. The experiment was carried out to determine the influence of the induced emotions (anger, joy, and sorrow) and stimulus types (picture and sentence) on the cognitive process load that may block the interactions among the constituents of working memory. The study subjects were 32 undergraduates who were similar with respect to age and education parameters and were especially instructed to attend to induced emotion by imitation of facial expression and to make a correct decision during the remainder calculation task. In the results, the stimulus types did not exhibit any difference but there was a significant difference among the induced emotion types. The difference was observed in slower response time at positive emotion(joy condition) as compared with other emotions(anger and sorrow). More specifically, error and delayed correct response rate for emotion types were analysed to determine which phase the slower response was associated with. Delayed responses of the joy condition by sentence-inducing stimulus were identified with the error rate difference, and those by picture-inducing stimulus with the delayed correct response rate. These findings not only suggest that induced positive emotion increased response time compared to negative emotions, but also imply that picture-inducing stimulus easily affords arithmetic fluctuation whereas sentence-inducing stimulus results in arithmetic failure.

• Korean Journal of Cognitive Science
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• v.20 no.4
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• pp.481-506
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• 2009

The purpose of the present research was to examine whether the attention mechanism employs physical or represented location of the cue and target. To achieve this, we have employed the paradigm of facilitation of response as well as inhibition of return. In the experiments, valid and invalid conditions were defined by the position consistency of the cue and the target in the aspect of either physical or represented location. We used auditory cue and visual target in Experiment 1 while visual cue and auditory target in Experiment 2. As a results, in Experiment 1, effect of facilitation of response in valid condition was found when the valid/invalid conditions were defined in the aspect of represented location. In Experiment 2, effect of facilitation of response in valid condition was found when the valid/invalid conditions were defined in the aspect of represented location. In all the other conditions, no effect was found when the conditions were defined in the aspect of physical location. No effects of inhibition of return were found in Experiment 2. These results imply the possibility that attention mechanism operates based on objects' represented location rather than on their physical location. More importantly, the present research suggests that it is necessary to separate represented location from physical location of the target and the cue in the experiment of facilitation of response and inhibition of return in the future.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.18 no.5
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• pp.185-196
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• 2023

This paper investigates the effects of entrepreneurs' cognitive biases on business opportunity evaluation, given their strong entrepreneurial spirit, which is characterized by innovation, proactivity, and risk-taking. When making decisions related to business activities, entrepreneurs typically make rational judgments based on their knowledge, experience, and the advice of external experts. However, in situations of extreme stress or when quick decisions are required, they often rely on heuristics based on their cognitive biases. In particular, we often see cases where entrepreneurs fail because they make decisions based on heuristics in the process of evaluating and selecting new business opportunities that are planned to guarantee the growth and sustainability of their companies. This study was conducted in response to the need for research to clarify the effects of entrepreneurs' cognitive biases on new business opportunity evaluation, given that the cognitive biases of entrepreneurs, which are formed by repeated successful experiences, can sometimes lead to business failure. Although there have been many studies on the effects of cognitive biases on entrepreneurship and opportunity evaluation among university students and general people who aspire to start a business, there have been few studies that have clarified the relationship between cognitive biases and social networks among entrepreneurs. In contrast to previous studies, this study conducted empirical surveys of entrepreneurs only, and also conducted research on the relationship with social networks. For the study, a survey was conducted using a parallel survey method using online mobile surveys and self-report questionnaires from 150 entrepreneurs of small and medium-sized enterprises. The results of the study showed that 'overconfidence' and 'illusion of control', among the independent variables of entrepreneurs' cognitive biases, had a statistically significant positive(+) effect on business opportunity evaluation. In addition, it was confirmed that the moderating variable, social network, moderates the effect of overconfidence on business opportunity evaluation. This study showed that entrepreneurs' cognitive biases play a role in the process of evaluating and selecting new business opportunities, and that social networks play a role in moderating the structural relationship between entrepreneurs' cognitive biases and business opportunity evaluation. This study is expected to be of great help not only to entrepreneurs, but also to entrepreneur education and policy making, by showing how entrepreneurs can use cognitive biases in a positive way and the influence of social networks.

• Science of Emotion and Sensibility
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• v.6 no.3
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• pp.63-72
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• 2003

This study investigated how cognitive style and training context influenced visual discrimination skill acquisition and transfer under time pressure. This experiment consisted of a screening session, a training session, and a transfer session using random polygon comparison tasks. Screening session was designed to separate participants according to their cognitive style (analytic or holistic). Training session was divided into difficult and easy conditions. In transfer session, participants compared polygon pairs in a novel task. The stimuli were presented for 1.5 seconds to examine the influence of time pressure. Through the all sessions, this experiment measured accuracy and response time. According to the results of this study, analytic group responded as quickly as holistic group in the beginning of training session because time pressure induced them to the holistic strategy. However, as training session progressed, their slopes of reaction time increased, suggesting that their own analytic style emerged. Holistic group showed flatter slopes than did analytic group for training session. Of interest is the slopes increased at the beginning of transfer session, suggesting that they developed analytic strategies in difficult training context. It is suggested individuals differently develop strategic processing skills depending on cognitive styles even under time pressure.