• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• v.8 no.2
• /
• pp.273-286
• /
• 1997

Objective：This study was designed to evaluate effects of methylphenidate(MPH) on event-related potentials(ERP) and continuous performance test(CPT) in attention-deficit hyperactivity disorder (ADHD) and to see the correlation between changes in ERP and changes in performance. Method：ERP and CPT were used to examine the acute effects of MPH(0.5mg/kg) in eleven ADHD boys(89-103 months old). Results：1) After MPH administration, P3 latency to nontarget stimuli at Fz was significantly decreased (p<0.01) and P2 amplitudes to target stimuli at Pz and at Oz and P3 amplitude to target stimuli at Cz were significantly increased(p<0.05). 2) Commission error and omission error in the CPT-X and commission error in the CPT-AX were decreased(p<0.01), and hits and perceptual sensitivity(d') in the CPT-X and d′ in the CPT-AX were increased(p<0.01). 3) The change of P3 latency to nontarget stimuli at Fz and the change of d′ in the CPT-X were negatively correlated(p<0.05), and the change of P2 amplitude to target stimuli at Pz and d′ in the CPT-AX were positively correlated(p<0.05). Conclusion：MPH improves change orienting reaction, the delivery of task relevant information, accuracy and perceptual sensitivity in ADHD. And the increase of ability to discriminate targets from non-targets reflects reduced evaluation time in large memory component task and enhanced change orienting reaction in simple task.

• Korean Journal of Cognitive Science
• /
• v.27 no.1
• /
• pp.1-25
• /
• 2016

The present study investigated the effect size of attention and consciousness on change detection. We confirmed the effect size of consciousness by comparing the condition which combined attention and consciousness and the condition of attention without consciousness. Then, we confirmed the effect size of attention by comparing the condition of attention without consciousness and the control condition which excluded attention and consciousness. For this purpose, change detection task and continuous flash suppression (CFS) were used. CFS renders a highly visible image invisible. In CFS, one eye is presented with a static stimulus, while the other eye is presented with a series of rapidly changing stimuli, such as mondrian patterns. The result is that the static stimulus becomes suppressed from conscious awareness by the stimuli presented in the other eye. We used a customized device with smartphone and google cardboard instead of stereoscope to trigger CFS. In Experiment 1-1, we reenacted some study to validate our experimental setup. Our experimental setup produced the duration of stimulus suppression that were similar to those of preceding research. In Experiment 1-2, we reenacted a study for attention without consciousness using an customized device. The results showed that attention without consciousness more strongly work as a cue. We think that it is reasonable to use CFS treatment employing smartphone and google cardboard for a follow-up study. In Experiment 2, when performing the change detection task, we measured the effect size of consciousness and attention by manipulating the consciousness level of cue. We used the method in which everything but the variable of interest kept being fixed. That way, the difference this independent variable makes to the action of the entire system can be isolated. We found that there was significant difference of correct response rate on change detection performance among different consciousness level of cue. In this study, we investigated that not only the role of attention and consciousness were different also we were able to estimated the effect size.

• Korean Journal of Health Psychology
• /
• v.16 no.3
• /
• pp.557-575
• /
• 2011

This study tried to examine the characteristics of attention deficits in patients with Obstructive Sleep Apenea(OSA) with different age levels, and to examine which indices of polysomnograms might be related to the indices of attention deficits in OSAs. Two age-level groups and a normal control group were subjected to two computerized attention tests, including a continuous performance test(CPT) and a change blindness task(CBT). In addition, the three groups were subjected to a Polysomnography to extract several sub-indicators of polysomnogram, and an Epworth Sleepiness Scale which measures subjective sleepiness. As results, the OSAs showed significantly more omission and commission errors in CPT, and they showed lower accuracy in CBT compared to the normal group. The results of a correlational analysis showed that attention deficits in OSA are significantly correlated with arterial oxygen saturation among sub-indicators of polysomnograms. In conclusion, OSAs seems to be less attentive, having difficulties in response inhibition, and having deficiencies in noticing important environmental changes. Age seems to make these deficiencies even worse. Especially, the relationship between attention deficiency and hypoxia which could cause irreversible cerebrum damage has an implication in cognitive impairment prevention through early treatment.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• v.7 no.2
• /
• pp.190-202
• /
• 1996

This study assessed psychiatrically referred 5-to 13-year-old children who presented inattention or hyperactivity as chief complaints. Demographic characteristics, primary diagnosis, and comorbid psychiatric conditions of them were identified, and they were assessed using questionnaires and neuropsychological tests. Primary diagnoses included ADHD, anxiety disorder, mental retardation, depression, oppositional defiant disorder, developmental language disorder and others. functional enuresis, conduct disorder, and developmental language disorder were among the secondarily diagnosed disorders. In patients diagnosed as ADHD, overall comorbidity rate was 55.3%. The disorders that frequently co-occured with ADHD were specific developmental disorder, conduct disorder, oppositional defiant disorder, anxiety disorder and other. ADHD groups with or without comorbidity differed in performance IQ and CPT scores. ADHD group differed from externalizing disorders group in the information subscore of IQ, MFFT, and CPT scores, and differed in teachers rating scales, the uncommunication factor of CBCL, and CPT card error compared with internalizing disorders group. The authors concluded that inattentive or hyperactive children should be assessed using various instruments to differentiate other disorders and to identify possible presence of comorbid conditions.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• v.19 no.2
• /
• pp.104-111
• /
• 2008

Objectives : The purpose of this study was to compare two subtypes of attention-deficit hyperactivity disorder (ADHD) and controls in their attention using ADHD diagnostic system (ADS), a kind of continuous performance test. Methods : Subjects of this study were 8 children with ADHD-predominantly inattentive type, 28 children with ADHD-combined type and 20 control children. Ages ranged from 5 to 14 years. The Korean Educational Development Institute version of the Wechsler Intelligence Scale for Children (KEDI-WISC) and the ADS were administered to all subjects to provide measures of intelligence and attention. Results : Significant differences were found in the ADS variables for the three groups. When compared with controls, the ADHD-predominantly inattentive type children scored significantly higher on the omission error at middle stage and later stage and ADHD-combined type children scored significantly higher on the omission error and reaction time at later stage. When compared with the other two groups, the ADHD-combined type children scored significantly higher on the commission error at all three stages. Conclusion : Our results suggest that the two subtypes of ADHD have different features in attention deficit. And there was a possibility that commission error is available variable to show cognitive characteristics of ADHD-combined type than any other ADS variables. Further studies are needed to evaluate this finding.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• v.17 no.2
• /
• pp.163-169
• /
• 2006

Objectives : The study was conducted to investigate the effect of intelligence ability on attention using Continuous Performance Test (CPT). Methods : 56 children with ADHD (52 boys, 4 girls) and 41 children in normal (28 boys, 13 girls) were sampled, their age range was 7 to 15. They performed IQ test and ADHD Diagnostic System (ADS) in order to examine intelligence and attention. Participants were divided into normal group and ADHD group, average IQ level children and superior IQ level children. Then ADS variables (omission error, commission error, reaction time, reaction time deviation, response sensitivity, and response criterion) were analyzed. Results : There was no significant interaction effect between group (normal, ADHD) and intelligence (average, superior). But there was significant difference between normal group and ADHD group in omission error, commission error, reaction time deviation, and response sensitivity. Also average level IQ group had significantly showed more omission, greater reaction time deviation, and lower response sensitivity than superior level IQ group. Conclusion : ADHD group has attention deficit than normal group, and CPT is available tool to detect attention problems. These findings indicate that intelligence can contaminate inattention and cognitive impulsivity thus it compensates for attention deficit. And it suggests that intelligence effect is considered in analyzing CPT in ADHD children.

• Journal of the Korean Society for Precision Engineering
• /
• v.17 no.3
• /
• pp.22-28
• /
• 2000

제조업의 경쟁력 제고를 위하여 시작된 선도 기술개발 사업의 하나인 '첨단생산시스템기술개발' 사업은 제 1 단계에서 FMS 핵심 기술 개발을, 제 2 단계에서는 CIM 기술 개발을 수행하였다. 1,2단계 기술 개발의 연속성 위에서 제 3 단계에서는 지능형 생산시스템(IMS: Intelligent Manufacturing System)을 구현하기 위하여 1999년 11월부터 연구가 시작되었다.

• 한국신재생에너지학회:학술대회논문집
• /
• 2008.10a
• /
• pp.157-160
• /
• 2008

본 연구에서는 디스크 이동식 폐타이어 열분해 실증 설비(10톤/일)를 설계, 제작 그리고 시운전을 통하여 열분해 설비의 안정적인 연속 운전이 가능함을 확인하였다. 시운전 결과 반응기 내부 온도는 $500{\sim}600^{\circ}C$, 내부 압력은 $-80{\sim}-100mmHg$, 체류시간은 $60{\sim}90min$ 범위에서 안정적인 열분해가 일어났다. 또한 이번 과제 수행을 통해NC 가스의 연소기를 개발 적용하여 NC 가스의 열분해 열원으로 사용 가능성을 확인하였으며, NC 가스 연소 시 대기 측정을 통하여 규제치도 만족함을 확인할 수 있었다. 지금까지 나온 결과는 장기 연속 운전과 scale-up을 위한 기초 자료가 될 것이다.

• Explosives and Blasting
• /
• v.29 no.2
• /
• pp.59-66
• /
• 2011

A variety of risks caused by natural, technological and biological hazards threaten a business continuity of an organization. Business continuity is very important issue for all organizations and its proper management may control success and failure of an organization. Business continuity plan (BCP) may be defined as a management process which provides a business continuity. BCP includes risk management, operational continuity plan, response/ recovery, exercise/study and crisis communication, etc. Risk management is a systematic method to identify, analyze, evaluate and treat emergency risks and risk assessment is composed of identifying, analyzing and evaluating emergency risks. Risk assesment is the first step for making BCP. In this study, risk assessment has been conducted for sewer laying project. Through assessing risks, 18 risks that may threaten the construction operation are identified and it is founded to be that high levels of risks which require treatment are 'collapse of excavation surface', 'breakage of ground infra-facilities', 'noise & dust dispersion' and 'rise of material costs'.

• Journal of The Korean Association For Science Education
• /
• v.19 no.4
• /
• pp.684-695
• /
• 1999

In this study, the 'extended science investigation' was conceptualized as a comprehensive science investigation contrasted with exercise of process and skill component and cookbook style experiment. The extended investigation tasks can be characterized with practical context. openness and continuity. The purpose of this study is to describe the change of students' cognitive engagement while they perform the extended science investigations and to explore how the characteristics of the extended investigation tasks affect the students' cognitive engagement. 128 7th graders attending coeducational school in Seoul were participated in this study. The questionnaire was implemented repeatedly to monitor students' cognitive engagement. And ten students were interviewed to explore the cause of the change of cognitive engagement. The result showed that there was no difference between directive traditional investigations in textbook and developed extended investigations in understanding of the content and whole process of investigations but participants' commitment was increased significantly in the extended science investigations. Especially the extent of students' understanding and commitment became higher in the second half than in the first half of the extended science investigations. The openness of the extended investigation tasks contributed on the increase of commitment. And the continuity of the tasks contributed on the increase of students' understanding in the second half of the extended science investigations.