• Journal of Dental Rehabilitation and Applied Science
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• v.24 no.3
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• pp.231-242
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• 2008

Purpose: The purpose of this study was to investigate the bond strength of the core-veneer interface in all ceramic systems. Material and Methods: The all ceramic systems tested with their respective veneer were IPS Empress 2 with IPS Eris, IPS e.max Press with IPS e.max Ceram and IPS-e.max ZirCAD with IPS e.max Ceram. Cores (N=36, N=12/group, diameter: 10mm, thickness: 3mm) were fabricated according to the manufacturer's instruction and cleaned with ultrasonic cleaner. The veneer(diameter: 3mm, thickness: 2mm) were condensed in stainless steel mold and fired on to the core materials. After firing, they were again ultrasonically cleaned and embedded in acrylic resin. The specimens were stored in distilled water at $37^{\circ}C$ for 1 week. The specimens were placed in a mounting jig and subjected to shear force in a universal testing machine(Z020, Zwick, Germany). Load was applied at close to the core-veneer interface as possible with crosshead speed of 1.00mm/min until failure. Average shear bond strengths(MPa) were analyzed with a one-way analysis of variance and the Tukey test(${\alpha}=.05$). The failed specimens were examinated by scanning electron microscopy(JSM-6360, JEOL, Japan). The pattern of failure was classified as cohesive in core, cohesive in veneer, mixed or adhesive. Results: The mean shear bond strength($MPa{\pm}SD$) were IPS e.max Press $32.85{\pm}6.75MPa$, IPS Empress 2 $29.30{\pm}6.51MPa$, IPS e.max ZirCAD $28.10{\pm}4.28MPa$. IPS Empress 2, IPS e.max Press, IPS e.max ZirCAD were not significantly different from each others. Scanning electron microscopy examination revealed that adhesive failure did not occur in any all ceramic systems. IPS Empress 2 and IPS e.max Press exhibited cohesive failure in both the core and the veneer. IPS e.max ZirCAD exhibited cohesive failure in veneer and mixed failure.

• The Journal of Korean Academy of Sensory Integration
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• v.7 no.1
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• pp.37-46
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• 2009

Background : Theory of Sensory Integration (SI) was initially developed with an effort to understand children's behavior by Jean Ayres and has been evolved with extensive research by occupational therapist practitioners and researchers since in the latter of the 20 century. With extension of recognition to SI, various professions begin to refer their clients who are children with sensory integration dysfunction. Upon those referrals, occupational therapists normally use Short Sensory Profile (SSP) to screen and decide whether SI therapeutic intervention is needed or not. Objective : Purpose of this study is (1) to examine any difference between different age groups and genders for children who are seven to nine years old; (2) to compare the score results of those Korean children with the original Standard which is established for American children: and (3) to compare tendency of response for each item between children with- and without SI dysfunction. This study was intended to validate test items of the SSP and determine whether the original standard of SSP is applicable for Korean children. Method : 155 students (81 for male, 74 for female) underwent SI evaluation using the Korean-translated SSP. 52 student (22 for male, 30 for female) were 7 years old, 54 students (32 for male, 22 for female) were 8 years old, 49 students (27for male, 22 for female) were 9 years old. Results : There is no significant difference of SSP score by neither age nor gender. In comparison the average score and sensory integrative disorder with the American Standard, there is significant difference on score of sub-item and total score. For six items, there is no significant difference on the tendency of response between children with- and without SI dysfunction. Conclusions : It is concluded that the original standard is suitable for Korean children aged seven to nine. The six test items that children without SI dysfunction shown similar tendency to respond are questionable to be appropriate as screening test item. It is suggested to proceed to do further item analysis study and extend the study to broad age groups, so develop the most appropriate Standard of SSP for Korean children.

• 대한공업교육학회지
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• v.38 no.2
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• pp.267-286
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• 2013

Recently, the advanced company has been sparing no efforts in improving necessary core knowledge and technology to achieve outstanding work performance. In this rapidly changing knowledge-based society, the company has confronted the task of creating a high value-added knowledge. The role of R&D workforce that corresponds to the characteristic and role of knowledge worker is getting more significant. As the life cycle of technical knowledge and skill shortens, in every industry, the technical knowledge and skill have become essential elements for successful business. It is difficult to improve competitiveness of the company without enhancing the competency of individual and organization. As the competency development which is a part of human resource management in the company is being spread now, it is required to focus on the research of determining necessary competency and to analyze the competency of a core organization in the research institute. 'H' is the semiconductor manufacturing company which has a affiliated research institute with its own R&D engineers. Based on focus group interview and job analysis data, vision and necessary competency were confirmed. And to confirm whether the required competency by job is different or not, analysis was performed by dividing members into workers who are in charge of circuit design and design before process development and who are in the process actualization and process development. Also, this research included members' importance awareness of the determined competency. The interview and job analysis were integrated and analyzed after arranging by groups and contents and the analyzed results were resorted after comparative analysis with a competency dictionary of Spencer & Spencer and competency models which are developed from the advanced research. Derived main competencies are: challenge, responsibility, and prediction/responsiveness, planning a new business, achievement -oriented, training, cooperation, self-development, analytic thinking, scheduling, motivation, communication, commercialization of technology, information gathering, professionalism on the job, and professionalism outside of work. The highly required competency for both jobs was 'Professionalism'. 'Attitude', 'Performance Management', 'Teamwork' for workers in charge of circuit design and 'Challenge', 'Training', 'Professionalism on the job' and 'Communication' were recognized to be required competency for those who are in charge of process actualization and process development. With above results, this research has determined the necessary competency that the 'H' company's affiliated research institute needs and found the difference of required competency by job. Also, it has suggested more enthusiastic education methods or various kinds of education by confirming the importance awareness of competency and individual's level of awareness about the competency.

• Neonatal Medicine
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• v.18 no.1
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• pp.76-81
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• 2011

Purpose: The object of this study was to evaluate the efficacy of early total parenteral nutrition with early amino acid in extremely low birth weight infant (ELBWI). Methods: We retrospectively analyzed the medical records of all ELBWIs who were born and admitted to Samsung Medical Center from January 2003 to December 2003 and January 2009 to December 2009 and alive at the time of discharge. Data for nutritional status and morbidities were compared between period 1 (2003, n=22), in which parenteral nutritional support was started gradually over several days and period 2 (2009, n=38), in which parenteral nutrition with amino acid was started as soon as possible after birth. Results: Compared to period 1, birth weight and Apgar score were lower in period 2. The intake amount of glucose, amino acid and total calorie was higher and the level of blood urea nitrogen was increased more from 7th day to 14th day after birth in period 2 when compared than period 1. The weight gain velocity was faster at 7th and 14th postnatal day in period 2. There were no differences in the incidence of necrotizing enterocolitis, moderate to severe bronchopulmonary dysplasia, and severe intraventricular hemorrhage (${\geq}$ Gr III) between two periods but, the incidence of periventricular leukomalacia(PVL) was significantly lower in period 2. Conclusion: Early initiation of total parenteral nutrition with early amino acid in ELBWIs was beneficial at weight gain with lowering catabolism and increasing anabolism. And it could be related with reducing the incidence of PVL.

• The Korean Journal of Nuclear Medicine
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• v.36 no.3
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• pp.166-176
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• 2002

Purpose: The purpose of this study is to investigate the effects of visual activation and quantitative analysis of regional cerebral blood flow. Visual activation was known to increase regional cerebral blood flow in the visual cortex in occipital lobe. We evaluated that change in the distribution of $^{99m}Tc-HMPAO$ (Hexamethyl propylene amine oxime) to reflect in regional cerebral blood flow. Materials and Methods: The six volunteers were injected with 925 MBq (mean ages: 26.75 years, n=6, 3men, 3women) underwent MRI and $^{99m}Tc-HMPAO$ SPECT during a rest state with closed eyes and visual stimulated with 8 Hz LED. We delineate the legion of interest and calculated the mean count per voxel in each of the fifteen slices to quantitative analysis. The ROI to whole brain ratio and regional index was calculated pixel to pixel subtraction visual non-activation image from visual activation image and constructed brain map using a statistical parameter map (SPM99). Results: The mean regional cerebral blood flow was increased due to visual stimulation. The increase rate of the mean regional cerebral blood flow which of the activation region in primary visual cortex of occipital lobe was $32.50{\pm}5.67%$. The significant activation sites using a statistical parameter of brain constructed a rendering image and image fusion with SPECT and MRI. Conclusion: Visual activation was revealed significant increase through quantitative analysis in visual cortex. Activation region was certified in Talairach coordinate and primary visual cortex (Ba17),visual association area (Ba18,19) of Brodmann.

• Clinical and Experimental Pediatrics
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• v.52 no.3
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• pp.346-350
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• 2009

Purpose : Since children under two years with suspected urinary tract infections (UTIs) cannot control urination, urine cultures in such children are usually performed via urine bags. This method is noninvasive but has a high contamination rate. We studied the contamination rate of bag urine culture in diagnosing UTI in infants under two years and the factors responsible for contamination. Methods : We examined patients under 2 years in whom urine culture through the urine bag method yielded over 105 colonies of a single pathogen. We defined UTI by referring to the guidelines of The Korean Society of Pediatric Nephrology, 2005. We examined the factors responsible for contamination according to sex, duration of urine collection, and whether diarrhea took place with contamination rate. Results : We examined 717 patients (412 males and 305 females). The contamination rate of one bag urine culture was 37.9%. Gender was not related to the contamination rate (P>0.05). Duration of urine collection showed an association with the contamination rate. The longer the duration of collecting urine, the higher was the contamination rate. Duration of urine collection was divided into three groups: first group, <2 hours; second group, 24 hours; and third group, ${\geq}4$ hours. Contamination rates were 30.0%, 42.2%, and 43.7% for the first, second, and third groups, respectively, with statistical significance (P=0.001). Diarrhea at admission had no impact on the contamination rate (P>0.05). Conclusion : The contamination rate of urine culture in the examined patients was 37.9%. Gender and diarrhea symptoms were not responsible for contamination. In infants with a suspected UTI, urine should be collected within 2 hours through the urine bag method. If urine collection takes >2 hours, the urine bag should be resterilized and reattached to the patient.

• Journal of Korean Society of Forest Science
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• v.86 no.3
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• pp.279-287
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• 1997

This study was carried out to identify the analysis of vegetation-environment relationships of the coniferous forests in subalpine districts of Mt. Chiri by two-way indicaton species analysis(TWINSPAN) and CCA. The results are summarized as follows; The subalpine coniferous forest in Mt. Chin was classified Abies koreana community group by the TWINSPAN method. The Abies koreana community group was classified Abies koreana-Pinus densiflora, Abies koreana-Quercus mongolicd and Abies koreana-Picea jezoensis. The Abies koreana-Quercus mongolica community classified into two subcommunities, typical and Pinus koraiensis subcommunity. The Abies koreana-Picea jezoensis community classified into three subcommunities such as typical, Taxus cuspidate and Cornus controversa subcommunity. The subalpine conifers commnities in Mt. Chiri could be classified into six vegetation units, which consisted of three vegetation communities and five subcommunities. The relationship between vegetation community and influencing environmental factors was analyzed by using the CCA ordination method. It was found that altitude, concentrations of $Ca^{++}$ and $Mg^{++}$ in soil were, major environmental variables, which influence the distribution of vegetation community in the first axis, and $Ca^{++}$ and altitude in the second axis. In the relations of communities and environmental factors by CCA, the optimal ecological habitats of Abies koreana-Pinus densiflora community could be located at low elevations, in which $Ca^{++}$ and $Mg^{++}$ are rich. Abies koreana-Quercus mongolica community prefers the sites in mid-elevation zone, in which $Ca^{++}$ and $Mg^{++}$ are medium level in soil. The optimum site for Abies koreana-Pinus koraiensis community and Abies koreana-Taxus cuspidata community could be high elevations in which $Ca^{++}$ and $Mg^{++}$ are poor. Abies koreana-Cornus controversa community is found in the site at low elevations where $Ca^{++}$ and $Mg^{++}$ are medium.

• Journal of the Korean Arthroscopy Society
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• v.16 no.2
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• pp.134-139
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• 2012

Purpose: To report the treatment results of arthroscopic osteochondroplasty in osteochondral lesion of the talus. Materials and Methods: This study included 32 patients who had osteochondral lesion of the talus treated with arthroscopic osteochondroplasty and were able to be followed up over 3 years from 1999 to 2007. The mean follow up period was 48 (38-108) months, and 22 male patients and 10 female patients with a mean age of 34 (20-56) years were included. Locations of lesion were evaluated with simple X-ray and magnetic resonance imaging (MRI), and severities of lesions were classified by Berndt and Harty classification. All cases were treated by arthroscopic debridement or microfracture. The treatment results were assessed by American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale and subjective and functional score of Kailkkonen. The group treated by arthroscopic microfracture was compared with the group treated by arthroscopic debridement. Results: The mean AOFAS ankle-hindfoot scale was significantly improved 53 (${\pm}7$) points preoperatively to 84 (${\pm}8$) points postoperatively (P<0.001). The mean subjective and functional score was also improved 55 (${\pm}8$) points preoperatively to 88 (${\pm}8$) points postoperatively with statistical significant (P<0.001). There were no relations between the severity of lesions and the postoperative functional score of ankle (P>0.05). There were no significant differences in the clinical results between the group treated with arthroscopic microfracture and the group treated with arthroscopic debridement (P>0.05). Conclusion: Arthroscopic osteochondroplasty of osteochondral lesion of the talus shows excellent result in terms of patients' satisfaction. There were no significant differences in the clinical results between arthroscopic microfracture group and debridement group.

• Journal of Korean Society of Forest Science
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• v.90 no.3
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• pp.380-387
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• 2001

The characteristics of ecological niche, breadth and overlap, for seventeen major tree species were evaluated in the natural deciduous forest in Mt. Chumbong area. Employed by the plot sampling method, the environmental gradient for vertical niche was based on the intensity of light within the forest, and that for horizontal niche was based on multi-dimensional resources in distribution pattern. The result showed that Fraxinus rhynchophylla had the highest value of vertical niche breadth and Maackia amurensis had the lowest, and Acer pseudo-sieboldianum had the highest value of horizontal niche breadth and Betula costata had the lowest. There was no significant correlation between both measures of niche breadth. However, the tolerance index for each species was positively correlated to the values of niche breadth. Spearman's rank correlation coefficients were applied to test the correlationship between the species ranks of tolerance index and those of two ecological niche breadths. The coefficient of $r_s=0.432$ ($P{\leq}0.1$) was not enough to support significant correlationship between the tolerance index and vertical niche breadth at the 95% probability. If Carpinus cordata, rarely reach canopy of the forest due to its own growth form, are excluded from the analysis, coefficient was calculated as $r_s=0.650$ ($P{\leq}0.01$), resulting in highly significant correlationship. The Spearman's rank correlation coefficient was $r_s=0.797$ ($P{\leq}0.01$) for tolerance indices and the values of horizontal niche breadth, indicating highly significant. Four distinctive species groups, produced by cluster analysis on the basis of ecological niche overlap for each pair of species, were in considerable accord with the positively associated species constellation pattern created by the inter-species association analysis.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.1
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• pp.12-26
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• 2010

This study was conducted to investigate current states and management of the protected trees in Gangwon-do. There were 701 protected trees in 42 species designated by 2008, which were distributed at 425 places. Major species were Zelkova serrata(29%), Pinus densiflora(24%), Ulmus davidiana var. japonica(11%), and Ginkgo biloba(5%). The protected trees played various roles in the villages, mostly as sacred trees(43%). The 51% of protected trees were 300 years or more in age, the 53% were more than 20 m in height, and the 57% were more than 300 cm in girth at breast height. The 69% of the protected trees have been designated for protection in 1982 and the rest have been designated by the local cities by 2008. The species number of the protected trees in Youngseo region was greater than that of the Youngdong region. The major species were Zelkova serrata (33%) and Pinus densiflora(17%) in Youngseo region, and were Pinus densiflora (38%) and Zelkova serrata(19%) in Youngdong region. The ratio of native species to exotic species was 33:1 in Youngseo region, and were 25:6 in Youngdong region. The 29% of protected trees were located in the field, 28% in the mountain, and 25% in the villages. The 45% of the ground were covered by herbaceous plants, 39% exposed, and 10% gravel mulch. Most of the protected trees had good growing conditions. The 70% of the protected trees were under good maintenance, and the rest were under undesirable conditions. The soil characteristics of the protected tree areas in Gangwon-do were not much different from those of Korean average. It seemed to be necessary to increase designation of protected trees based on the tradition, history, local value and academic application in Gangwon-do. In addition, it is desirable to suggest plans to utilize and manage protected tree areas for enhancing the value of natural heritages in Gangwon-do.