• Nuclear Engineering and Technology
• /
• v.40 no.7
• /
• pp.615-624
• /
• 2008

In this paper, the contribution of task types and error types involved in the human-related unplanned reactor trip events that have occurred between 1986 and 2006 in Korean nuclear power plants are analysed in order to establish a strategy for reducing the human-related unplanned reactor trips. Classification systems for the task types, error modes, and cognitive functions are developed or adopted from the currently available taxonomies, and the relevant information is extracted from the event reports or judged on the basis of an event description. According to the analyses from this study, the contributions of the task types are as follows: corrective maintenance (25.7%), planned maintenance (22.8%), planned operation (19.8%), periodic preventive maintenance (14.9%), response to a transient (9.9%), and design/manufacturing/installation (6.9%). According to the analysis of the error modes, error modes such as control failure (22.2%), wrong object (18.5%), omission (14.8%), wrong action (11.1 %), and inadequate (8.3%) take up about 75% of the total unplanned trip events. The analysis of the cognitive functions involved in the events indicated that the planning function had the highest contribution (46.7%) to the human actions leading to unplanned reactor trips. This analysis concludes that in order to significantly reduce human-induced or human-related unplanned reactor trips, an aide system (in support of maintenance personnel) for evaluating possible (negative) impacts of planned actions or erroneous actions as well as an appropriate human error prediction technique, should be developed.

• Journal of Ginseng Research
• /
• v.40 no.1
• /
• pp.55-61
• /
• 2016

Background: A number of neurological and neurodegenerative diseases share impaired cognition as a common symptom. Therefore, the development of clinically applicable therapies to enhance cognition has yielded significant interest. Previously, we have shown that activation of lysophosphatidic acid receptors (LPARs) via gintonin application potentiates synaptic transmission by the blockade of $K^+$ channels in the mature hippocampus. However, whether gintonin may exert any beneficial impact directly on cognition at the neural circuitry level and the behavioral level has not been investigated. Methods: In the current study, we took advantage of gintonin, a novel LPAR agonist, to investigate the effect of gintonin-mediated LPAR activation on cognitive performances. Hippocampus-dependent fear memory test, synaptic plasticity in the hippocampal brain slices, and quantitative analysis on synaptic plasticity-related proteins were used. Results: Daily oral administration of gintonin for 1 wk significantly improved fear memory retention in the contextual fear-conditioning test in mice.We also found that oral administration of gintonin for 1 wk increased the expression of learning and memory-related proteins such as phosphorylated cyclic adenosine monophosphate-response element binding (CREB) protein and brain-derived neurotrophic factor (BDNF). In addition, prolonged gintonin administration enhanced long-term potentiation in the hippocampus. Conclusion: Our observations suggest that the systemic gintonin administration could successfully improve contextual memory formation at the molecular and synaptic levels as well as the behavioral level. Therefore, oral administration of gintonin may serve as an effective noninvasive, nonsurgical method of enhancing cognitive functions.

• Journal of the Korean Society of Safety
• /
• v.29 no.1
• /
• pp.47-53
• /
• 2014

The application of advanced Main Control Room(MCR) is accompanied with lots of changes and different forms and features through the virtue of new digital technologies. The characteristics of these digital technologies and devices give many opportunities to the interface management, and can be integrated into a compact single workstation in advanced MCR so that workers can operate the plant with minimum physical burden under any operation conditions. However, these devices may introduce new types of human errors and thus a means to evaluate and prevent such errors is needed, especially those related to characteristics of digital devices. This paper reviewed the new type of human error hazards of tasks based on digital devices and surveyed researches on physiological assessment related to human error. An experiment was performed to verify human error hazards by physiological responses such as EEG which was measured to evaluate the cognitive workload of operators. And also, the performances of four tasks which are representative in human error hazard tasks based on digital devices were compared. Response time, ${\beta}$ power spectrum rate of each task by EEG, and mental workload by NASA-TLX were evaluated. In the results of the experiment, the rate of the ${\beta}$ power was increased in the task 1 and task 4 which are searching and navigating task and memory task of hierarchical information, respectively. In case of the mental workload, in most of evaluation items, task 1 and 4 were highly rated comparatively. In this paper, human error hazards might be identified by highly cognitive workload. Conclusively, it was concluded that the predictive method which is utilized in this paper and an experimental verification can be used to ensure the safety when applying the digital devices in Nuclear Power Plants (NPPs).

• Journal of Korean language education
• /
• v.28 no.2
• /
• pp.37-60
• /
• 2017

This research has its basis with focus on the way Korean native speakers recognize Chinese Korean-learners' pronunciation. The objective of the study is to lay the cornerstone for establishing effective teaching-learning strategies for the education of the Korean phonetic system. In this study, the results of the experiment are presented which shows how native speakers of Korean identify Chinese Korean-learners' pronunciation of consonants. In the first place, stimulation tones were created from the original utterances of Chinese Korean-learners and seven scripts were made through the Pratt program. In addition, the subjects were asked to choose what the phonetic materials sounded like. The results of the research are represented as the ratio of frequency of Korean native speakers' response to each utterance to the total frequency. In addition, the paired t-test was taken in order to explore any relatedness to the changes in the level of proficiency of the Korean phonetic system, ranging from beginners to advanced learners. The outcome shows that the mistakes which Chinese Korean-learners make in pronouncing the consonants of Korean are relatively well-reflected in Korean native speakers' auditory cognitive reactions. To put it concretely, there is some difficulty in differentiating lax consonants from aspirates in the cases of plosives and affricates, but relatively little trouble with fortes. However, it is revealed that there is also a slight difference in relation to articulatory positions in detailed aspects. To provide an effective teaching method for the Korean phonetic system, it is essential to comprehend learners' phonetic mistakes through the precise analysis of data in terms of 'production.' Also, a more meticulous observation of 'phenomena' must be made through verification from the view of 'reception,' as attempted in this study. A more thorough diagnosis by applying methodology makes it possible to lay the foundation for developing effective teaching-learning strategies for the instruction of the Korean phonetic system. This study has its significance in making such attempts.

• The Korean Journal of Physiology and Pharmacology
• /
• v.25 no.4
• /
• pp.281-296
• /
• 2021

The beneficial effects of hypoxic preconditioning are abolished in the diabetes. The present study was designed to investigate the protective effects and mechanisms of repeated episodes of whole body hypoxic preconditioning (WBHP) in db/db mice. The protective effects of preconditioning were explored on diabetes-induced vascular dysfunction, cognitive impairment and ischemia-reperfusion (IR)-induced increase in myocardial injury. Sixteen-week old db/db (diabetic) and C57BL/6 (non-diabetic) mice were employed. There was a significant impairment in cognitive function (Morris Water Maze test), endothelial function (acetylcholine-induced relaxation in aortic rings) and a significant increase in IR-induced heart injury (Langendorff apparatus) in db/db mice. WBHP stimulus was given by exposing mice to four alternate cycles of low (8%) and normal air O₂ for 10 min each. A single episode of WBHP failed to produce protection; however, two and three episodes of WBHP significantly produced beneficial effects on the heart, brain and blood vessels. There was a significant increase in the levels of brain-derived neurotrophic factor (BDNF) and nitric oxide (NO) in response to 3 episodes of WBHP. Moreover, pretreatment with the BDNF receptor, TrkB antagonist (ANA-12) and NO synthase inhibitor (L-NAME) attenuated the protective effects imparted by three episodes of WBHP. These pharmacological agents abolished WBHP-induced restoration of p-GSK-3β/GSK-3β ratio and Nrf2 levels in IR-subjected hearts. It is concluded that repeated episodes of WHBP attenuate cognitive impairment, vascular dysfunction and enhancement in IR-induced myocardial injury in diabetic mice be due to increase in NO and BDNF levels that may eventually activate GSK-3β and Nrf2 signaling pathway to confer protection.

• Biomolecules & Therapeutics
• /
• v.27 no.1
• /
• pp.71-77
• /
• 2019

Previous studies have shown that spinosin was implicated in the modulation of sedation and hypnosis, while its effects on learning and memory deficits were rarely reported. The aim of this study is to investigate the effects of spinosin on the improvement of cognitive impairment in model mice with Alzheimer's disease (AD) induced by $A{\beta}_{1-42}$ and determine the underlying mechanism. Spontaneous locomotion assessment and Morris water maze test were performed to investigate the impact of spinosin on behavioral activities, and the pathological changes were assayed by biochemical analyses and histological assay. After 7 days of intracerebroventricular (ICV) administration of spinosin ($100{\mu}g/kg/day$), the cognitive impairment of mice induced by $A{\beta}_{1-42}$ was significantly attenuated. Moreover, spinosin treatment effectively decreased the level of malondialdehyde (MDA) and $A{\beta}_{1-42}$ accumulation in hippocampus. $A{\beta}_{1-42}$ induced alterations in the expression of brain derived neurotrophic factor (BDNF) and B-cell lymphoma-2 (Bcl-2), as well as inflammatory response in brain were also reversed by spinosin treatment. These results indicated that the ameliorating effect of spinosin on cognitive impairment might be mediated through the regulation of oxidative stress, inflammatory process, apoptotic program and neurotrophic factor expression,suggesting that spinosin might be beneficial to treat learning and memory deficits in patients with AD via multi-targets.

• The Journal of Industrial Distribution & Business
• /
• v.12 no.2
• /
• pp.29-40
• /
• 2021

Purpose: In this study, with the transaction amount of foreign direct Purchase and foreign direct sales increasing, South Korea is in a situation where foreign direct sales are focused on China. We looked at the impact of consumer innovation and site characteristics on repurchase ability among the characteristics of overseas direct purchase consumers as a way to make direct overseas sales to various overseas countries. Research design, data and methodology: Consumer innovativeness consists of four variables: functional, hedonistic, social, and cognitive, and the site characteristics consisted of four variables: product price, product assortment, convenience, and service. The study was conducted on consumers with foreign direct purchase experience, and was finally used in 252 additional analyses. Results: The main findings of this study were first, that the impact on the degree of re-purchase among consumer innovativeness of foreign direct purchase consumers had a significant impact in the order of cognitive innovativeness, hedonistic innovativeness, and functional innovativeness. Social innovativeness did not affect the degree of re-purchase. Second, site characteristics have been found to have a significant impact on the degree of re-purchase in order of product assortment, commodity price, and service. Convenience did not affect the degree of re-purchase. Conclusions Taken together these results can be called the biggest characteristic of the cognitive innovativeness of the consumer's inclination to use the overseas direct purchase, the price or quick response of the goods sold on the site is a factor that affects the re-purchase, above all it is important to have a variety of products. We will present this element as a way to make direct sales abroad to various countries. In addition, foreign direct purchase is a lot of transactions in China, the United States, EU, but the share of China is high in foreign direct sales, and the U.S. and EU have a very low performance, it is important to consider the reasons why they prefer Korean products in China to study the social and cultural characteristics of U.S. and European consumers in the future, and to support and active marketing that companies and sellers can increase sales.

• Journal of the Korean Society of Safety
• /
• v.37 no.2
• /
• pp.35-42
• /
• 2022

When an accident occurs, the associated human activity is typically regarded as a "human error," or a temporal deviation. On the other hand, if the accident results in a serious loss or if it evokes a social issue, the person determined to be responsible may be punished with a "violation" of related laws or regulations. However, as Heinrich stated, it is neither appropriate nor reasonable in terms of probability theory and cognitive science to distinguish whether it is a "human error" or a "violation" with a criterion of resultant accident severity. Nonetheless, some in society get on the social climate to strengthen regulations on workers who have caused accidents, especially violations. This response can present a social issue due to the lack of systematic judgment procedure which distinguishes violations from human errors. The purpose of this study was to develop an objective and systematic procedure to assess whether workers' activities which induced industrial accidents should be categorized as violations rather than human errors. Various analysis techniques for the determination of violation procedure were investigated and compared using an analysis approach method. An appropriate technique was not found, however, for judging the culpability of intentional violations. As an alternative, this study developed the process of creating violations, based on cognitive procedure, as well as the criteria to determine and categorize an activity as a violation. In addition, the developed procedure was applied to cases of industrial accidents and nuclear power plant issues to test its practical applicability. The study demonstrated that the proposed model could be used to determine the existence of a violation even in the case of multiple workers who work simultaneously.

• Korean Journal of Psychosomatic Medicine
• /
• v.30 no.2
• /
• pp.80-98
• /
• 2022

Posttraumatic stress disorder (PTSD) is well known to have a limited response to drug treatment. Many recently published clinical care guidelines recommend trauma-focused psychotherapies such as cognitive processing therapy (CPT) and prolonged exposure therapy (PE) as first-line treatment and medication such as serotonin reuptake inhibitors and venlafaxine as second-line treatment. Current review introduces the session composition and contents of CPT and presents various CPT studies that show therapeutic effect for civilian and veterans/military with PTSD. In order for clinicians to help effectively patients with PTSD, it is necessary to learn and actively use evidence-based trauma-focused psychotherapies including CPT and PE.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.10 no.4
• /
• pp.811-817
• /
• 2009

The rapid growth of network based IT systems has resulted in continuous research of security issues. Probe intrusion detection is an area of increasing concerns in the internet community. Recently, a number of probe intrusion detection schemes have been proposed based on various technologies. However, the techniques, which have been applied in many systems, are useful only for the existing patterns of probe intrusion. They can not detect new patterns of probe intrusion. Therefore, it is necessary to develop a new Probe Intrusion Detection technology that can find new patterns of probe intrusion. In this paper, we proposed a new network based probe intrusion detector(NePID) using anomaly traffic analysis and fuzzy cognitive maps that can detect intrusion by the denial of services attack detection method utilizing the packet analyses. The probe intrusion detection using fuzzy cognitive maps capture and analyze the packet information to detect syn flooding attack. Using the result of the analysis of decision module, which adopts the fuzzy cognitive maps, the decision module measures the degree of risk of denial of service attack and trains the response module to deal with attacks. For the performance evaluation, the "IDS Evaluation Data Set" created by MIT was used. From the simulation we obtained the max-average true positive rate of 97.094% and the max-average false negative rate of 2.936%. The true positive error rate of the NePID is similar to that of Bernhard's true positive error rate.