• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.18 no.2
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• pp.122-132
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• 2008

The purpose of this study is to present the basic materials of a developmental counterplan by assessing prevalence of musculoskeletal symptoms and characteristics of work-related ergonomic risk factors. The prevalence of musculoskeletal symptoms of 64 vineyard workers was investigated by using a self-reported questionnaire. And the vineyard workers' tasks were also collected and analyzed during 9-month period by observing and videotaping methods to identify the ergonomic risk factors. The prevalence rate of musculoskeletal symptoms of female(84.4%) was much higher than that of male(62.5%) and a total prevalence rate was 73.4%. There was no different prevalence of musculoskeletal symptoms between age over 60 years and under 60 years. The prevalence rates of musculoskeletal complaints for each body part were 48.4%, 42.2%, and 35.9% for the wrist, legs/knee, and shoulder, respectively. In postural risk analysis, 7 works(REBA score) represented the high risk tasks such as delivering harvest boxed(12), picking cluster(11) and so on. The main works(exposure score) were orderly ranked as picking cluster(1590), pruning branch(388), and cluster thinning(327). The risk factors of vineyard work were identified as follows: shoulder flexion(${\geq}45^{\circ}$), wrist Flex./Ext.(${\geq}15^{\circ}$), hand force(power/pinch-grip), and prolonged standing(${\geq}4hr$). The engineering solutions including an improvement of hand tools, working process, and working environment should be applied to the high risky tasks in order to resolve the ergonomic problems. The administrative solutions such as improving a distribution of resting time, an exercise cure, an early recognition of symptoms and rehabilitation might be another solution for reducing musculoskeletal symptoms in vineyard workers.

• Childhood Kidney Diseases
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• v.19 no.2
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• pp.125-130
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• 2015

Introduction: This study investigated whether renal and bladder ultrasonography (RBUS) findings performed in children with the first incidence of febrile urinary tract infection (UTI) can predict UTI recurrence, high-grade vesicoureteral reflux (high-grade VUR), or acquired renal scarring (aRS). Methods: In all, 917 children who were admitted to our hospital from January 2001 to October 2010, owing to the first incidence of febrile UTI were enrolled in this study. All children underwent RBUS during admission. The mean follow-up was 7.9 months (standard deviation $[SD]{\pm}13.3$). UTI recurrence rates were calculated according to various clinical parameters. By using bivariate and multiple logistic regression analyses, we determined whether age, sex, abnormal RBUS findings, abnormal dimercaptosuccinic acid renal scan findings, or RBUS findings parameters were predictive of UTI recurrence, high-grade VUR, or aRS. Results: On RBUS, hydronephrosis and congenital anomaly of the kidney and urinary tract significantly predicted UTI recurrence. A small kidney, hydroureter, hydronephrosis, cortical thinning, and increased parenchymal echogenicity significantly predicted high-grade VUR. However, their odds ratios (OR) are low compared to normal RBUS findings (recurrent UTI: OR 0.432 and 0.354 vs. 0.934, respectively, high-grade VUR: .019, 0.329, 0.126, 0.058, and 0.188 vs. 2.082, respectively). No RBUS findings significantly predicted aRS. Recurrent UTI, high-grade VUR, and abnormal RBUS findings significantly predicted aRS (OR of 4.80, 4.61, and 2.58, respectively). Conclusion: RBUS is necessary to exclude severe congenital renal scarring, obstructive uropathy, and renal abscess at the first incidence of febrile UTI and is helpful in determining the need for subsequent clinical imaging.

• Korea-Australia Rheology Journal
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• v.11 no.3
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• pp.255-263
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• 1999

Blends of two thermotropic liquid crystalline polymers, HX2000 and Vectra A950, were prepared by melt blending. Effects of transesterification on these blends are investigated by comparing properties of the blends with and without the addition of an inhibitor, in terms of blend miscibility and rheology. Both the uninhibited and inhibited blends are found to be largely immiscible with very limited miscibility in HX2000-rich phase. No strong evidence indicates the occurrence of transesterification in the blends in the solid state. Dynamic rheological behaviour, such as shear storage modulus (G') and shear loss modulus (G") as a function of frequency, of the blends are interpreted by a three-zone model. HX2000 shows terminal-zone and plateau-zone behaviour, whilst Vectra A950 shows plateau-zone and transition-zone behaviour. The un- inhibited blends show plateau-zone behaviour up to 50% Vectra A950 content and the inhibited blends show plateau-zone behaviour up to 60% Vectra A950 content. Compositional dependence of the complex viscosities of the uninhibited and inhibited blends displayed positive deviations from additivity, which is a characteristic feature for the immiscible thermoplastic blends. When under steady shear, both the uninhibited and inhibited blends show shear thinning behaviour and their viscosities decrease monotonically with the addition of Vectra A950. Compositional dependence of the steady shear viscosities of the two sets of blends displayed negative deviations from additivity and the uninhibited blends were more viscous than the inhibited blends for the full composition range. Although limited agreement with the Cox-Merz rule is found for the inhibited blends, these two sets of blends, in general, do not follow the rule due to their liquid crystalline order and two-phase morphology. Despite being immiscible blends, transesterification, such as polymerization, in the blends might occur during the rheological characterization, supported by the facts that uninhibited blends show HX2000-dominant behaviour at lower Vectra A950 content and are more viscous than the inhibited blends. The addition of transesterification inhibitor in such blends is advised if only physical mixing is desired.ired.

• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.1
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• pp.51-56
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• 2005

To understand the chemical changes in the streamwater and contribution of subsurface discharge during the storm event, we analyzed electric conductivity (EC), anions, and cations in Gwangneung deciduous and coniferous forest catchment. The stream water samples were collected three times in 2004 by using an auto-sampler: September 7-9 (E040907-D and -C; where D and C indicate deciduous and coniferous forest catchment, respectively), September 11-13 (E040911-D and -C), and September 16-18 (E040916-D and -C). We found a negative relationship between discharge intensity and EC in streamwater. The E040911 and E040916 showed slack change of stream discharge in comparison to E040907 due to contribution of base flow recharged by much precipitation. Moreover, NO/sub 3//sup -/ concentrations in E040911-C were highest, which may have resulted from forest management such as thinning in 2004. The relationship between pH and alkalinity in stream water showed that much of stream water have been recharged through subsurface. We conclude that subsurface discharge highly influences streamwater quality in a forested catchment, and the seperation of stream water discharge is therefore necessary to sustainable water management.

• Journal of Korean Neurosurgical Society
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• v.60 no.6
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• pp.749-754
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• 2017

Objective : To quantitatively measure the degree of bone flap resorption (BFR) following autologous bone cranioplasty and to investigate factors associated with BFR. Methods : We retrospectively reviewed 29 patients who underwent decompressive craniectomy and subsequent autologous bone cranioplasty between April 2005 and October 2014. BFR was defined as : 1) decrement ratio ([the ratio of initial BF size/craniectomy size]-[the ratio of last BF/craniectomy size]) >0.1; and 2) bone flap thinning or geometrical irregularity of bone flap shape on computed tomographic scan or skull plain X-ray. The minimal interval between craniectomy and cranioplasty was one month and the minimal follow-up period was one year. Clinical factors were compared between the BFR and no-BFR groups. Results : The time interval between craniectomy and cranioplasty was $175.7{\pm}258.2$ days and the mean period of follow up was $1364{\pm}886.8$ days. Among the 29 patients (mean age 48.1 years, male : female ratio 20 : 9), BFR occurred in 8 patients (27.6%). In one patient, removal of the bone flap was carried out due to severe BFR. The overall rate of BFR was $0.10{\pm}0.11$ over 3.7 years. Following univariate analysis, younger age ($30.5{\pm}23.2$ vs. $54.9{\pm}13.4$) and longer follow-up period ($2204.5{\pm}897.3$ vs. $1044.1{\pm}655.1$) were significantly associated with BFR (p=0.008 and 0.003, respectively). Conclusion : The degree of BFR following autologous bone cranioplasty was 2.7%/year and was associated with younger age and longer follow-up period.

• Journal of the Korean Wood Science and Technology
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• v.48 no.3
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• pp.345-363
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• 2020

This study was conducted to identify the effect of kerfing and incising pretreatments on high-temperature drying characteristics of cedar and larch boxed-heart timbers with a cross section of less than 150 mm. The result showed that the pretreatments have made a significant difference regarding surface check and shrinkage. Although the kerfing was suitable as a pretreatment to reduce the occurrence of surface check, the incising was not suitable as a pretreatment since the knives of timber joined together, causing the conversion to the surface checks. The shrinkage showed a significant result that the final moisture content was reduced in the order of incising, kerfing, and kerfing-incising after the drying process based on the pretreatment condition. Twist was more affected by the grain angle than the anisotropy of the juvenile wood, and there was no effect of pretreatments.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.27 no.1
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• pp.283-295
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• 1997

The purpose of this study was to evaluate the Waters' views, panoramic and periapical radiograms as well as clinical symptoms in the diagnosis of maxillary sinusitis. The author analyzed the types of mucosal thickenings, the types of bony wall changes, the pathologic changes of antral floors and total amount of agreement on radiograms in 495 patients with 505 maxillary sinuses which demonstrated radiographic changes. The results were obtained as follows : 1. 125 cases (24.8％) showed the mucosal thickening of antral floor and lateral wall (Type II), 106 cases (20.9％) showed the mucosal thickening around the whole antral wall (Type N) and 75 cases (14.8％) showed increased radiopacity of whole antrum. 2. Among 505 cases of mucosal thickenings, 319 cases<63.2％) showed the bony wall changes: 114 cases (35.9％) showed the thinning of lateral walls, 105 cases (32.8％) showed the thickening of lateral walls and 47 cases(14.7％) showed indistinct antral walls. 3. Among 6 types of mucosal thickenings, the incidence of bony wall changes was high in type VI(73.3％) and in type IV(71.6％). 4. 139 cases(25.1％) showed no pathologic change of antral floor, 127 cases(22.9％) showed the indistinct antral floor and 122 cases (22.1％) showed the halo appearance of antral floor on panoramic and periapical radiograms. 5. 449 cases (88.9％) showed apparent increased radiopacity and 47 cases(9.3％) showed suspicious increased radiopacity on Waters' views. 280 cases (71.6％) showed apparent increased radiopacity and 88 cases (22.5％) showed suspicious increased radiopacity on panoramic radiograms. And 141 cases (31.6％) showed apparent increased radiopacity and 133 cases(33.4％) showed suspicious increased radiopacity on periapical radiograms.

• Archives of Plastic Surgery
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• v.41 no.5
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• pp.529-534
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• 2014

Background In 2012, a new anatomic breast implant of form-stable silicone gel was introduced onto the Korean market. The intended use of this implant is in the area of aesthetic breast surgery, and many reports are promising. Thus far, however, there have been no reports on the use of this implant for breast reconstruction in Korea. We used this breast implant in breast reconstruction surgery and report our early experience. Methods From November 2012 to April 2013, the Natrelle Style 410 form-stable anatomically shaped cohesive silicone gel-filled breast implant was used in 31 breasts of 30 patients for implant breast reconstruction with an acellular dermal matrix. Patients were treated with skin-sparing mastectomies followed by immediate breast reconstruction. Results The mean breast resection volume was 240 mL (range, 83-540 mL). The mean size of the breast implants was 217 mL (range, 125-395 mL). Breast shape outcomes were considered acceptable. Infection and skin thinning occurred in one patient each, and hematoma and seroma did not occur. Three cases of wound dehiscence occurred, one requiring surgical intervention, while the others healed with conservative treatment in one month. Rippling did not occur. So far, complications such as capsular contracture and malrotation of breast implant have not yet arisen. Conclusions By using anatomic breast implants in breast reconstruction, we achieved satisfactory results with aesthetics better than those obtained with round breast implants. Therefore, we concluded that the anatomical implant is suitable for breast reconstruction.

• Journal of the Institute of Convergence Signal Processing
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• v.13 no.2
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• pp.70-76
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• 2012

In this paper, an automatic extraction method of glomerulus region from human renal tissue image is presented. The important information reflecting the state of kidneys richly included in the glomeruli, so it should be the first step to extract the glomerulus region from the renal tissue image for the further quantitative analysis of the renal condition. Especially, there is no clear difference between the glomerulus and other tissues, so the glomerulus region can not be easily extracted from its background by the existing segmentation methods. The outer edge of a glomerulus region is regarded as a common property for the regions of this kind ; a two- dimensional Gaussian distribution is used to convolve with an original image first and then the image is thresholded at this blurred image ; a closed curve corresponding to the outer edge can be obtained by usual pattern processing skills like thinning, branch-cutting, hole-filling etc., Finally, the glomerulus region can be obtained by extracting the area in the original image surrounded by the closed curve. The glomerulus regions are correctly extracted by 85 percentages and experimental results show the proposed method is effective.

• Corrosion Science and Technology
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• v.18 no.2
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• pp.55-60
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• 2019

Corrosion failure in the convection part of peak load boiler (PLB) of the district heating system led to water leakage. Herein, Internal Rotary Inspection System (IRIS) inspection was employed to examine wall thinning and the cause of leakage in the flue tube. The corrosive products of the turbulator and tube were investigated using scanning electron microscope combined with energy dispersive spectroscopy, X-ray diffraction, and inductively coupled plasma (ICP). Majority of the serious corrosion damage was observed near the turbulator located in the upper flue tube. ICP analysis of the boiler water revealed oxide formation of sodium chloride in the lower end part of the flue tube. A cross-sectional view of the turbulator revealed the presence of double-layers of the oxide film, indicating environmental change during operation associated with water leakage. The outer surface of the turbulator consisted of the acid oxides such as $NO_x$ and $SO_x$ along with sodium and chloride ions. Dew-point corrosion is hypothesized as the main cause for the formation of acid oxides in the region of contact of the flue tube and the turbulator.