• Investigative Magnetic Resonance Imaging
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• v.6 no.2
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• pp.158-165
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• 2002

Purpose : To evaluate the effect of Gd-DTPA on signal intensity of diffusion-weighted magnetic resonance(MR) image and apparent diffuse coefficient (ADC) in dog brain with hype racute stroke. Materials and methods : Experimental canine model of hyperacute cerebral infarction was made by selective intraarterial embolization with particulate embolic material. Diffusion-weighted MR imaging was performed in five dogs at 1 hour after the embolization of internal carotid artery. After intravenous bolus injection of Gd- DTPA, additional 11 diffusion-weighted MR images were serially obtained from 2 minutes to 90 minutes after injection in each dog. The author evaluated findings of hyperacute cerebral infarction on diffusion-weighted MR imaging, and calculated mean signal intensity and mean ADC in infarcted region and contralateral normal region. Statistical analysis of mean signal intensity, mean ADC and contrast-noise ratio before and after Gd-DTPA injection was performed. Results : Hyperacute cerebral infarction developed in all five dogs on diffusion-weighted MR images obtained 1 hour after embolization. The area of hyperacute infarction had steady increase in signal intensity on diffusion-weighted MR image and decrease in ADC. In normal perfusion area, decrease in signal intensity was observed at 2 minutes the Gd-DTPA injection, whereas ADC did not changed. Conclusion : Intravenous injection of Gd-DTPA had no influence on ADC in both hyperacute infarction and normally perfused are a, but caused initial transient signal reduction in normally perfused area on diffusion-weighted MR image due to susceptibility effect of Gd-DTPA. It is important to calculate ADC in evaluating the effect of diffusion after injection of Gd-DTPA.

• Investigative Magnetic Resonance Imaging
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• v.18 no.3
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• pp.200-207
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• 2014

Purpose : We evaluated the diagnostic value of susceptibility-weighted imaging (SWI) for the detection of developmental venous anomaly (DVA). Materials and Methods: Retrospective review of 1068 brain MR examinations found 28 DVAs in 28 patients (2.6%) on contrast-enhanced T1-weighted images. SWI, T2, and FLAIR images of 28 patients with DVA and 28 sex- and age-matched control patients without DVA were analyzed by blinded readers on each type of sequences. All images were independently reviewed by two radiologists who were blinded to other MR imaging finding. In cases of discrepancy, two reviewers reached a consensus later. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of each MR sequence for the detection of DVA were determined. Statistical analysis was performed by using the Mcnemar test. The significance level was p < 0.05. Results: The sensitivity, specificity, PPV, and NPV of SWI for the detection of DVA were 85.7%, 92.9%, 92.3%, and 86.7%, respectively. T2 and FLAIR images showed sensitivity of 35.7% and 35.7%, specificity of 92.9% and 96.4%, PPV of 83.3% and 90.9%, and NPV of 59.1% and 60.0%, respectively. On SWI, the sensitivity and NPV for the detection of DVAs were significantly higher than those of T2 and FLAIR images (p < 0.05). Conclusion: SWI was sensitive and specific for the detection of DVA.

• Cement
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• s.199
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• pp.24-27
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• 2013

갈수록 복잡해져만 가는 경영 환경 속에서 기업의 위기는 일상이 되었다. 경영진들은 위기 극복을 강조하며 구성원들이 업무에 더욱 몰입하도록 독려한다. 그러나 구성원들의 마음을 헤아리지 못한 일방적인 강조로는 구성원들의 반감이나 불신을 사게 되고 결국 원하는 결과를 얻지 못하게 될 수 있다. 여기서는 LG경제연구원 전재권 선임연구원의 '위기 경영 일수록 공감이 필요하다' 보고서를 통해 둔감해진 구성원들의 마음을 일깨우고 자발적인 열정을 이끌어 내기 위한 방안을 살펴본다.

• 프린팅코리아
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• s.16
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• pp.146-151
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• 2003

디지털경제는 고객의 시대라 말할 수 있으며 그 사업방식은 기업에서 고객 중심으로 이동하고 있다. 원가와 규모의 경제, 원자재 확보가 주요 중심사였던 대량생산 시대를 넘어 규격과 신뢰성, 내구성, 사후서비스를 강조하며 ISO14000, TQM, QS9000, ISO9000 등의 국제 인증이 강조되던 품질시대도 뒤로하고 글로벌시대를 맞아 차별화 된 제품, 빠른 회전과 신속배달, 개인화 서비스, 편리성, 사용의 용이성을 내용으로 하는 가상고객시대로 치닫는 것이다.

• KOREAN POULTRY JOURNAL
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• v.38 no.8 s.442
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• pp.74-75
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• 2006

노동부와 산업안전관리공단에서는 매년 7월 첫째주를 ‘산업안전보건강조주간’이라 지정하여 산업재해예방에 공로가 큰 산업안전보건 관계자들의 노고를 치하하고 산재예방에 관한 기술과 정보를 교류하는 행사를 거행한다. 본고는 지난 3일부터 개최된 ‘제39회 산업안전보건강조주간행사’에서 올해의 산재예방유공 정부포상자로 동탑산업훈장을 수상한 (주)제일바이오 심광경 대표이사를 만나 수상소감을 들어보았다.

• 월간산업보건
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• s.376
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• pp.38-43
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• 2019

매년 7월 첫째 주는 안전보건의 중요성을 되새기는 기간이다. 올해도 7월 1일부터 5일까지 국민의 안전의식을 높이는 '2019 산업안전보건강조주간 행사'가 서울 코엑스에서 펼쳐졌다. 내 외빈과 유관기관 관계자 등 4만여 명이 참석한 가운데 다양한 프로그램이 진행된, 열기 가득했던 시간 속으로 들어가보자.

• Investigative Magnetic Resonance Imaging
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• v.17 no.2
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• pp.91-100
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• 2013

Purpose : To evaluate the usefulness of cervicothoracic spine sagittal T2-weighted images (CT SAG T2WIs) included in routine lumbar spine MRI. Materials and Methods: Institutional review board approval was obtained and informed consents were waived for this retrospective study. The study group comprised 2,113 patients who underwent lumbar spine MRI from January 2005 to December 2005. CT SAG T2WIs were added in the routine lumbar spine MRIs. Radiologic reports were reviewed retrospectively for pathologic lesions on CT SAG T2WIs by one radiologist. Information of additional cervical or thoracic spine MRI and/or CT for further evaluation of positive findings on CT SAG T2WIs and their treatment were collected by retrospectively reviewing medical records. Results: The CT SAG T2WIs revealed 142 pathologic lesions in 139 (6.58%) of the 2,113 patients. They were easily obtained without positional change in a scan time of less than 2 minutes. Additional cervical or thoracic spine MRI and/or CT for positive findings on CT SAG T2WIs were performed in 13 patients. Seven patients underwent surgical treatment. Conclusion: CT SAG T2WIs included in routine lumbar spine MRI were useful in finding the pathologic lesions in cervicothoracic spine for the patients who assumed to have lesions in lumbar spine.

• Journal of The Korean Association of Information Education
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• v.20 no.6
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• pp.629-644
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• 2016

The purpose of this study was to investigate the effects of whole-task sequencing emphasis manipulation on expertise acquisition in web based complex task. To achieve the purpose, emphasis manipulation sequencing type is composed of a simple emphasis manipulation, a snowballing manipulation, and a full emphasis manipulation sequencing and participants was drawn from a pool of 93 undergraduate students sampled for the study. According to the findings, a snowballing manipulation group invested significantly lower cognitive load than a full emphasis manipulation group but did not a simple emphasis manipulation group. Based on these findings, though complex task is included of high interactivity owing to real task, learner cannot suffer cognitive overload because emphasis manipulation which can view the whole task and the part task in parallel provides meta cognition for learner. And whole-task sequencing emphasis manipulation affects to transfer. The snowballing emphasis manipulation group invested significantly higher than simple emphasis manipulation group and full emphasis manipulation group. Based on these findings, the snowballing manipulation which learner use whole-task sequencing and part-task sequencing simultaneously contribute to understandings and ability to solve problems for complex task and it will in turn, lead to expertise acquisition.

• Journal of The Korean Association For Science Education
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• v.34 no.8
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• pp.787-794
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• 2014

The purpose of this study was to examine the science writing and perception of students who experienced the argument-based claim and evidence writing approach. One hundred and eight grade 11 students were assigned to an experimental group, while 99 grade 12 students were assigned to a comparative group in their earth science classes. Students' science writings on two science topics were scored using an analytic rubric developed in this study. The comparison of experimental and comparative groups in science writing was carried out using an independent two samples t-test. Students' perception on the instruction was examined using an open-ended survey. Science writing by the experimental group scored significantly higher than that by the comparative group, except for the big idea of 'green energy'. For six concepts in 'green energy' and four concepts in 'plate tectonics, there were more students in the experimental group than the comparative group who indicated them in their science writing. Students' perception on the instruction was positive in that they mentioned planning and conducting inquiry, citing of claims and evidence, and developing inquiry questions were helpful in science learning. The results of this study imply that the argument-based claim and evidence writing approach should be implemented in science classrooms for students to develop a conceptual framework for science.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.7
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• pp.1594-1600
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• 2005

Recently many researches have been studied in the human vision model to solve the Wblem of the machine vision. Starting from research on the human visual system, first, we investigate the mechanisms of retina through physiological and biological evidence. In retina, input data was processed information processing that was data reduction edge detection, and emphasizing region. The processed image was recognized by region. In this paper, we proposed retinal algorithms that process data reduction and edge detection by the wavelet transform and emphasize region contrast. In experiments, the proposed model simulates processing the retina outputs in the levels and compares with outputs.