• Sleep Medicine and Psychophysiology
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• v.10 no.1
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• pp.52-60
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• 2003

Objectives: Stage 1 sleep provides important information regarding interpretation of nocturnal polysomnography, particularly sleep onset. It is a short transition period from wakeful consciousness to sleep. The lack of prominent sleep events characterizing stage 1 sleep is a major obstacle in automatic sleep stage scoring. In this study, utilization of simultaneous EEG and EOG processing and analyses to detect stage 1 sleep automatically were attempted. Methods: Relative powers of the alpha waves and the theta waves were calculated from spectral estimation. A relative power of alpha waves less than 50% or relative power of theta waves more than 23% was regarded as stage 1 sleep. SEM(slow eye movement) was defined as the duration of both-eye movement ranging from 1.5 to 4 seconds, and was also regarded as stage 1 sleep. If one of these three criteria was met, the epoch was regarded as stage 1 sleep. Results were compared to the manual rating results done by two polysomnography experts. Results: A total of 169 epochs were analyzed. The agreement rate for stage 1 sleep between automatic detection and manual scoring was 79.3% and Cohen’s Kappa was 0.586 (p<0.01). A significant portion (32%) of automatically detected stage 1 sleep included SEM. Conclusion: Generally, digitally-scored sleep staging shows accuracy up to 70%. Considering potential difficulty in stage 1 sleep scoring, accuracy of 79.3% in this study seems to be strong enough. Simultaneous analysis of EOG differentiates this study from previous ones which mainly depended on EEG analysis. The issue of close relationship between SEM and stage 1 sleep raised by Kinnari remains a valid one in this study.

• Clinical and Experimental Pediatrics
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• v.51 no.9
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• pp.971-976
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• 2008

Purpose : Surveillance for detecting and managing latent tuberculosis infection (LTBI) is a key component of tuberculosis control. The classic surveillance tool, the tuberculin skin test (TST), may have some limitations when used in the Bacillus Calmette-$Gu{\acute{e}}rin$ (BCG)-vaccinated population. The object was to perform a blood test $QuantiFERON^{(R)}$-TB Gold In Tube (QFT-G IT) based on the detection of interferon-$\gamma$ ($IFN-{\gamma}$) released by T cells in response to Mycobacterium tuberculosis-specific antigens, and to compare the efficacy of this new diagnostic tool for LTBI with that of TST. Methods : For six months, between October 1, 2006 and April 30, 2007, data were collected from 111 patients under 15 years of age at Severance Children's Hospital. TST and QFT-G IT tests were performed with children with or without contact histories of tuberculosis. In addition to these tests, we examined comparative data from 29 adults who had tuberculosis, to detect false negative rates in the QFT-G IT method. Results : Thirty-three children had household contact histories. In this group, 15% and 42% of cases were found to be positive using the QFT-G IT assay and TST, respectively. Agreement was low between these two tests (${\kappa}=0.39$). In the adult active tuberculosis group, the QFT-G IT false negative rate defined as a positive culture and a negative QFT-G IT result was 12.5%. Conclusion : In diagnosing LTBI in children, the usefulness of a whole-blood $IFN-{\gamma}$ assay employing TB-specific antigens will be revealed only by examining additional longitudinal clinical data; this study serves as a starting point in that process.

• 대한공업교육학회지
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• v.33 no.2
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• pp.97-119
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• 2008

The purpose of this research is to clarify the elements of the function of the role of industrial high schools that its experts perceived. The content of this research is verify the function element required for the performance of the role of specialized education through content validity ratio(CVR). This research adopted the method of literature research and Delphi method, which is to collect and come to an agreement of the opinions of the 26 research panels. The first round is constructed by the semi-constructed questionnaire for the analysis of the opinions of the panels by inductive method. The second round is to categorize the result of the first one into 7 domains, and asked each category by Likert's 5 scale checklists, and statistically analyzed mean, medium, standard deviation, and quartile. The third round is to statistically analyze Mean, standard deviation, medium, and validity ratio(CVR) to reassure the opinions of the panels on the basis of the result of the first one. The categorized contents of the function required for the performance of the specialized education in this research is 'in-service visit and in-service training', 'licence acquiring education', 'employment counseling and job employment information', 'custom-made education connected with industry', 'career education' and 'enhancement of basic career competency'. The panels are divided into professors, teachers, professionals, and policy administrators, and they verified the validity rate of the function role and priority of emphasis. The result showed that the tendency of the education is converting from physical function-centered education to education of emotional attitude and competence of thought.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.6
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• pp.647-653
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• 2007

The ultimate objective of this study is to develop a reliable oxygen-enriched combustion techniques especially for the case of the flue gas recycling in order to reduce the $CO_2$ emissions from practical industrial boilers. To this end a systematic numerical investigation has been performed, as a first step, for the resolution of the combusting flame characteristics of lab-scale LNG combustor. One of the important parameters considered in this study is the level of flue gas recycling calculated in oxygen enriched environment. As a summary of flame characteristics, for the condition of 100% pure $O_2$ as oxidizer without any flue gas recycling, the flame appears as long and thin laminar-like shape with relatively high flame temperature. The feature of high peak of flame temperature is explained by the absence of dilution and heat loss effects due to the presence of $N_2$ inert gas. The same reasoning is also applicable to the laminarized thin flame one, which is attributed to the decrease of the turbulent mixing. These results are physically acceptable and consistent and further generally in good agreement with experimental results appeared in open literature. As the level of $CO_2$ recycling increases in the mixture of $O_2/CO_2$, the peak flame temperature moves near the burner region due to the enhanced turbulent mixing by the increased amount of flow rate of oxidizer stream. However, as might be expected, the flue gas temperature decreases due to presence of $CO_2$ gas together with the inherent feature of large specific heat of this gas. If the recycling ratio more than 80%, gas temperatures drop so significantly that a steady combustion flame can no longer sustain within the furnace. However, combustion in the condition of 30% $O_2/70% $ $CO_2$ can produce similar gas temperature profiles to those of conventional combustion in air oxidizer. An indepth analyses have been made for the change of flame characteristics in the aspect of turbulent intensity and heat balance.

• Asia pacific journal of information systems
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• v.18 no.1
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• pp.53-77
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• 2008

In recent years, although numbers of corporations are bringing in PMO, they seem to be indifferent to PMO performance measurement. This demonstrates that there are also other reasons beside performance measurement of information systems (IS) project being ambiguous by introducing PMO; the lack of acknowledging the concrete function of PMO, and the scarcity of empirical study about the effect of PMO on the project members and project performance. In this sense, this study is aimed at proposing a new research model in which project success factors (i.e., standardization, management advocacy, and staff expertise) affect PMO capability (i.e., knowledge management, resources management, and problem solving competency) positively, leading to project performance (i.e., task outcomes, psychological outcomes, and organizational outcomes) eventually. To empirically test the research model, data are surveyed from PMO department and IS department. To prove the validity of the proposed research model, PLS analysis is applied with valid 132 questionnaires. By employing PLS technique, the measurement reliability and validity of research variables are tested and the path analysis is conducted to do the hypothesis testing. The path analysis results can be organized into 7 ways in large scale. First, standardization of project success factors has a positive association with knowledge management, resources management, and problem solving competency of PMO capabilities. The findings of this result indicate that the multiple or single project management should satisfy standardization in order to operate an effective PMO. Second, management advocacy of project success factors has a positive association with knowledge management, resources management, and problem solving competency. Management advocacy refers to the willingness of management to provide the required resources and authority for project success. There is agreement among researchers regarding the importance of management advocacy for favorable PMO capability. Third, staff expertise of project success factors has a positive association with knowledge management, resources management, and problem solving competency. The findings of this result indicate that the formation of an exceptional consultant or members with a proficient knowledge for staff expertise of project member is the key factor to elevate the PMO capability. Past research suggests that experience and knowledge and the resultant familiarity with the problem faced can be an important determinant of PMO capability. A capable project with appropriate staff expertise means that it enjoys a diversity of abilities and experiences. Fourth, knowledge management competency of PMO capabilities has a positive impact on psychological outcomes but has no direct effect on task outcomes and organizational outcomes. In domestic case of S. Korea, PMO was finally introduced to many other corporations in 2005 though it started bringing in 2000. Therefore, it had neither a significant impact on the task outcomes nor organizational outcomes by lacking the contents and the infrastructure of the knowledge management because the knowledge consolidation and management period of PMO is comparatively shorter by terms than other foreign nations. Fifth, resources management competency of PMO capabilities has a positive association with task outcomes, psychological outcomes, and organizational outcomes. In addition, problem solving competency of PMO capabilities has a positive association with task outcomes, psychological outcomes, and organizational outcomes. Therefore, the findings of this results stress that PMO capabilities has a positive impact on project performance. Sixth, according to the path analysis of the hypothesis, which suggested in this research, problem solving competency is the PMO capability which is the key success factor for task, psychological, and organizational outcomes as an integrated performance model. Further, the analysis reveals that problem solving competency is an important factor for integrated performance model. The finding is in line with past IS research, which affirms that the work of IS projects is essentially a problem solving endeavor. Seventh, in the path analysis of the hypothesis in this research, the path of the management advocacy $\rightarrow$ problem solving competency $\rightarrow$ organizational outcomes appears to be the most important and strongest path. In brief, the finding of this study suggests that project success factors influence PMO capability positively, and project performance as well. From the results, it can be concluded that PMO helped great improve the project success rate and project performance. This study advances research on PMO capability in three important aspects. First, the findings of our study have implications for IS theory and future research. Our study contributes to IS theory by synthesizing concepts from PMO research and project management research with those in IS research. We proposed and tested PMO capability of IS projects and the findings of our investigation provided some preliminary answers to some of the questions raised. Secondly, this thesis does not only help depicting the concept of IT governance but also approaches empirically. It makes a gradual approach to the main content, step by step, in contrary of simple standard, scholastic way of thinking. Finally, we argued that this task-oriented(technical) view is not sufficient to adequately conceptualize IS project performance. Hence, we applied that the research on organization teams, which provides a flip viewpoint to that of project management research in that it gives more weight for psychological outcomes of organizational work groups, can be very helpful in reconceptualizing the IS project performance construct. The limitations of this study are also discussed to provide research directions for future research.

• Journal of Biomedical Engineering Research
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• v.25 no.1
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• pp.11-19
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• 2004

Stage 1 sleep provides important information regarding interpretation of nocturnal polysomnography, particularly sleep onset. It is a short transition period from wakeful consciousness to sleep. Lack of prominent sleep events characterizing stage 1 sleep is a major obstacle in automatic sleep stage scoring. In this study, we attempted to utilize simultaneous EEC and EOG processing and analyses to detect stage 1 sleep automatically. Relative powers of the alpha waves and the theta waves were calculated from spectral estimation. Either the relative power of alpha waves less than 50％ or the relative power of theta waves more than 23％ was regarded as stage 1 sleep. SEM (slow eye movement) was defined as the duration of both eye movement ranging from 1.5 to 4 seconds and regarded also as stage 1 sleep. If one of these three criteria was met, the epoch was regarded as stage 1 sleep. Results f ere compared to the manual rating results done by two polysomnography experts. Total of 169 epochs was analyzed. Agreement rate for stage 1 sleep between automatic detection and manual scoring was 79.3％ and Cohen's Kappa was 0.586 (p＜0.01). A significant portion (32％) of automatically detected stage 1 sleep included SEM. Generally, digitally-scored sleep s1aging shows the accuracy up to 70％. Considering potential difficulties in stage 1 sleep scoring, the accuracy of 79.3％ in this study seems to be robust enough. Simultaneous analysis of EOG provides differential value to the present study from previous oneswhich mainly depended on EEG analysis. The issue of close relationship between SEM and stage 1 sleep raised by Kinnariet at. remains to be a valid one in this study.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.3
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• pp.517-524
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• 2005

Despite the widespread use of chloral hydrate with hydroxyzine in the sedation of children, there is little agreement among pediatric dentists regarding its therapeutic dosage for the management of very uncooperative young children. Also, increasing concern has been raised with respect to its frequent failure to provide adequate levels of sedation when used according to the manufacturer's recommended dosage. Therefore, there has been many suggestions with respect to sedative effectiveness and safety of varying drug dosage, and some pediatric dental articles have advocated dosages exceeding manufacturer's recommendations. This study was performed to compare the effectiveness and safety in behavior management of the manufacturer's recommended dose of chloral hydrate(50mg/kg) with those of a higher dose(70mg/kg) used together with hydroxyzine(2mg/kg) and nitrous oxide(50%) when young children were sedated for dental treatment. The following results were obtained; 1. II group(70mg/kg) displayed higher mean score compared to I group(50mg/kg) with regard to the degree of sleep, crying, movement and overall behavior. The difference was statistically significant(p<0.05). 2. In comparison of success rates for sedation between the two groups, I group and II group showed 38.7% and 71.0% success rates respectively. An analysis of variance was statistically significant(p<0.05). 3. Comparing the occurrence rate hypoxia between the two groups, there were 22.6% and 19.4% occurrence of hypoxia in I group and II group. An analysis of variance was not statistically significant(p>0.05).

• Korean Journal of Agricultural and Forest Meteorology
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• v.19 no.1
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• pp.19-26
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• 2017

Surface air temperature ($T_{air}$) is a key variable for the meteorology and climatology, and is a fundamental factor of the terrestrial ecosystem functions. Satellite remote sensing from the Moderate Resolution Imaging Spectroradiometer (MODIS) provides an opportunity to monitor the $T_{air}$. However, the several problems such as frequent cloud cover and mountainous region can result in substantial retrieval error and signal loss in MODIS $T_{air}$. In this study, satellite-based $T_{air}$ was estimated under both clear and cloudy sky conditions in Gangwon Province using Aqua MODIS07 temperature profile product (MYD07_L2) and GCOM-W1 Advanced Microwave Scanning Radiometer 2 (AMSR2) brightness temperature ($T_b$) at 37 GHz frequency, and was compared with the measurements from the Automated Mountain Meteorology Stations (AMOS). The application of ambient temperature lapse rate was performed to improve the retrieval accuracy in mountainous region, which showed the improvement of estimation accuracy approximately 4% of RMSE. A simple pixel-wise regression method combining synergetic information from MYD07_L2 $T_{air}$ and AMSR2 $T_b$ was applied to estimate surface $T_{air}$ for all sky conditions. The $T_{air}$ retrievals showed favorable agreement in comparison with AMOS data (r=0.80, RMSE=7.9K), though the underestimation was appeared in winter season. Substantial $T_{air}$ retrievals were estimated 61.4% (n=2,657) for cloudy sky conditions. The results presented in this study indicate that the satellite remote sensing can produce the surface $T_{air}$ at the complex mountainous region for all sky conditions.

• Journal of radiological science and technology
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• v.36 no.2
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• pp.123-129
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• 2013

This study investigated the rate of setup variance by the rotating unbalance of gantry in image-guided radiation therapy. The equipments used linear accelerator(Elekta Synergy TM, UK) and a three-dimensional volume imaging mode(3D Volume View) in cone beam computed tomography(CBCT) system. 2D images obtained by rotating $360^{\circ}$and $180^{\circ}$ were reconstructed to 3D image. Catpan503 phantom and homogeneous phantom were used to measure the setup errors. Ball-bearing phantom was used to check the rotation axis of the CBCT. The volume image from CBCT using Catphan503 phantom and homogeneous phantom were analyzed and compared to images from conventional CT in the six dimensional view(X, Y, Z, Roll, Pitch, and Yaw). The variance ratio of setup error were difference in X 0.6 mm, Y 0.5 mm Z 0.5 mm when the gantry rotated $360^{\circ}$ in orthogonal coordinate. whereas rotated $180^{\circ}$, the error measured 0.9 mm, 0.2 mm, 0.3 mm in X, Y, Z respectively. In the rotating coordinates, the more increased the rotating unbalance, the more raised average ratio of setup errors. The resolution of CBCT images showed 2 level of difference in the table recommended. CBCT had a good agreement compared to each recommended values which is the mechanical safety, geometry accuracy and image quality. The rotating unbalance of gentry vary hardly in orthogonal coordinate. However, in rotating coordinate of gantry exceeded the ${\pm}1^{\circ}$ of recommended value. Therefore, when we do sophisticated radiation therapy six dimensional correction is needed.

• The Journal of the Petrological Society of Korea
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• v.25 no.3
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• pp.241-252
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• 2016

In this paper, in order to test the possibility of applying K feldspar $pIR-IRSL_{290}$ signal(read out at $290^{\circ}C$) to date old terrace sediments(up to ~ 200 ka, MIS 7) in Korea, we investigated luminescence properties of $pIR-IRSL_{290}$ signals in K feldspar extracts from 27 marine and fluvial terrace sediment samples, and these were compared with those of quartz OSL and conventional K feldspar $IRSL_{50}$ (readout at $50^{\circ}C$) signals. The averaged $2D_0$ value of K feldspar $pIR-IRSL_{290}$ growth curves was ~ 700 Gy, which is consistent with that of $IRSL_{50}$ signal, and this is 3 times higher than that for quartz OSL (~ 250 Gy) on average. Where possible, K feldspar $pIR-IRSL_{290}$ ages were compared with quartz OSL and conventional $IRSL_{50}$ ages. Our preliminary K feldspar $pIR-IRSL_{290}$ ages were older than quartz OSL ages by about 200%, while fading rate-corrected conventional $IRSL_{50}$ ages are in good agreement with those based on quartz OSL. This seems to indicate the possibility of K-feldspar $pIR-IRSL_{290}$ age overestimation due to the presence of unbleachable $pIR-IRSL_{290}$ signals, even with a prolonged exposure to sunlight. Both quartz OSL and K-feldspar $pIR-IRSL_{290}$ signals for the samples from Noeum fluvial terrace and Gusan fault site were all in dose saturation level, thus unable to estimate the formation ages of the sediments. However, $2D_0$ values derived from the dose response growth curves strongly indicate that the Noeum fluvial terrace sediments have formed before 109-140 ka, while the fluvial sediments from Gusan fault were desposited before 100-105 ka. Further, this seems to suggest that the previous quartz OSL ages of ~40-50 ka for Gusan fault sediments should be the underestimated ones due to dose saturation problem.