• Imaging Science in Dentistry
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• v.50 no.2
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• pp.105-115
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• 2020

Purpose: This study investigated the position of the hyoid bone and its relationship with airway dimensions in different skeletal malocclusion classes using cone-beam computed tomography (CBCT). Materials and Methods: CBCT scans of 180 participants were categorized based on the A point-nasion-B point angle into class I, class II, and class III malocclusions. Eight linear and 2 angular hyoid parameters(H-C3, H-EB, H-PNS, H-Me, H-X, H-Y, H-[C3-Me], C3-Me, H-S-Ba, and H-N-S) were measured. A 3-dimensional airway model was designed to measure the minimum cross-sectional area, volume, and total and upper airway length. The mean crosssectional area, morphology, and location of the airway were also evaluated. Data were analyzed using analysis of variance and the Pearson correlation test, with P values <0.05 indicating statistical significance. Results: The mean airway volume differed significantly among the malocclusion classes(P<0.05). The smallest and largest volumes were noted in class II (2107.8±844.7 ㎣) and class III (2826.6±2505.3 ㎣), respectively. The means of most hyoid parameters (C3-Me, C3-H, H-Eb, H-Me, H-S-Ba, H-N-S, and H-PNS) differed significantly among the malocclusion classes. In all classes, H-Eb was correlated with the minimum cross-sectional area and airway morphology, and H-PNS was correlated with total airway length. A significant correlation was also noted between H-Y and total airway length in class II and III malocclusions and between H-Y and upper airway length in class I malocclusions. Conclusion: The position of the hyoid bone was associated with airway dimensions and should be considered during orthognathic surgery due to the risk of airway obstruction.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.1
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• pp.30-35
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• 2017

In this study, we measured the natural frequencies of aluminum honeycomb sandwich beams using digital image correlation technique. The vibration images were captured using two high speed digital cameras and the images were converted to displacements by the digital image correlation technique. Displacement data in time domain were tranformed to frequency domain data by fast Fourier transform software. To reduce noise invoked by random exitation, a spectrum averaging technique and Savitsky-Golay digital filter were adopted. A conventional vibration measurement using an accelerometer and a finite element analysis were performed to compare the results by high speed digital camera measurement method. In conclusion, new method using high speed digital cameras and digital image correlation technique can measure the vibration of beam structures and can be applied to bio-structures where sensors cannot be attached.

• Journal of Periodontal and Implant Science
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• v.40 no.1
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• pp.19-24
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• 2010

Purpose: It has been suggested that primary implant stability plays an essential role in successful osseointegration. Resonance frequency analysis (RFA) is widely used to measure the initial stability of implants because it provides superior reproducibility and non-invasiveness. The purpose of this study is to investigate whether the fractal dimension from the panoramic radiograph is related to the primary stability of the implant as represented by RFA. Methods: This study included 22 patients who underwent dental implant installation at the Department of Periodontology of Seoul National University Dental Hospital. Morphometric analysis and fractal analysis of the bone trabecular pattern were performed using panoramic radiographs, and the implant stability quotient (ISQ) values were measured after implant installation using RFA. The radiographs of 52 implant sites were analyzed, and the ISQ values were compared with the results from the morphometric analysis and fractal analysis. Results: The Pearson correlation showed a linear correlation between the ISQ values of RFA and the parameters of morphometric analysis but not of statistical significance. The fractal dimension had a linear correlation that was statistically significant. The correlation was more pronounced in the mandible. Conclusions: In conclusion, we suggest that the fractal dimension acquired from the panoramic radiograph may be a useful predictor of the initial stability of dental implants.

• Ocean Systems Engineering
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• v.6 no.2
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• pp.143-159
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• 2016

Cargo, such as a Tension Leg Platform (TLP), Semi-submersible platform (Semi), Spar or a circular Floating Production Storage and Offloading (FPSO), are frequently dry-transported on a Heavy Lift Vessel (HLV) from the point of construction to the point of installation. The voyage can span months and the overhanging portions of the hull can be subject to frequent wave slamming events in rough weather. Tie-downs or sea-fastening are usually provided to ensure the safety of the cargo during the voyage and to keep the extreme responses of the cargo, primarily for the installed equipment and facilities, within the design limits. The proper design of the tie-down is dependent on the accurate prediction of the wave slamming loads the cargo will experience during the voyage. This is a difficult task and model testing is a widely accepted and adopted method to obtain reliable sea-fastening loads and extreme accelerations. However, it is crucial to realize the difference in the inherent stiffness of the instrument that is used to measure the tri-axial sea fastening loads and the prototype design of the tie-downs. It is practically not possible to scale the tri-axial load measuring instrument stiffness to reflect the real tie-down stiffness during tests. A correlation method is required to systematically and consistently account for the stiffness differences and correct the measured results. Direct application of the measured load tends to be conservative and lead to over-design that can reflect on the overall cost and schedule of the project. The objective here is to employ the established correlation method to provide proper high-frequency responses to topsides and hull design teams. In addition, guidance for optimizing tie-down design to avoid damage to the installed equipment, facilities and structural members can be provided.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1681-1685
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• 2013

Background: Head and neck SCC is a common cancer related to various factors. IL-10, a pleiotropic cytokine produced by macrophages, T-helper-2 cells, and B lymphocytes, is thought to play a potential pathogenetic or therapeutic role in a number of human conditions, such as inflammation, autoimmunity and cancer. The present study was designed to evaluate the relation between tissue expression, serum and salivary levels of IL-10 in head and neck squamous cell carcinomas (HNSCCs) and their correlation with clinicopathologic features. Materials and Methods: Samples were collected from 30 patients with HNSCCs and 24 healthy volunteers. IHC analysis was used to examine the tissue expression and ELISA was employed to measure serum and salivary levels. Results: Our study showed tissue expression of IL-10 to be significantily higher in patients (P: 0.001), but there was no relation between tissue expression, serum and salivary levels of the marker (P>0.05). Also except for a positive correlation between tissue expression of IL-10 and stage (P: 0.044), there was no relation between this marker and clinicopathologic features. There was no correlation between serum and salivary levels in either patients or controls. Conclusions: It seems there is no correlation between level of IL-10 in serum and saliva and this marker in saliva and serum does not reflect tissue expression.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.1
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• pp.1-8
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• 2011

This study is about the limits of GTEM cell using correlation factor between the OATS(Open area Test Site) and the GTEM cell. First, the field strengths at the 10 m distance OATS and in GTEM cell to obtain the experimental correlation factor are measured. Also, the EMI limits of radiated power are derived in GTEM cell as 3 position method is inversely transformed. The field strengths that calculated from theoretical models by 3 and 15 position methods are programmed and compared with measured data at the OATS. As the EMI limits of GTEM cell is newly defined, it will be use to substitute GTEM cell for OATS to efficiently measure EMI(Electromagnetic Interference).

• Journal of Korean Academy of Nursing
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• v.24 no.4
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• pp.529-544
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• 1994

For most parents their child's illness and hospitalization is strssful. Internal stress and over anxiousness leads to uncertainty. Parents have a variety of ways of coping when faced with such stress factors, especialy when the child has cancer. The purpose of this study was to examine the relationship between uncertainty in illness and mastery and coping styles in parents of pediatric cancer patients, and further to identify differences between three groups of subjects. A cross-sectional descriptive correlational design was used in this study to investigate the relationship among the three groups. The sample was composed of 59 parents of children with cancer in pediatric wards in three hospitals in Seoul : 21 in Group 4 with a child newly diagnosed with cancer : 25 in Group B, with a child under treatment and rehospitalized with a relapse : and 13 in Group C, with a child with a terminal cancer, A formalized questionnaire which included demegrapic information and consisted of 75 items was used in this study ; The Parent Perception of Uncertainty Scale(PPUS) adapted form Mishel’s Uncertainty in Illness Scale, Pearlin & Schooler's Mastery Scale(MS) and Folkman & Lazarus’s Ways of Coping Checklist(WCC) were used to measure the variables : uncertainty in illness, mastery, and coping styles. A pretest was conducted on the questionnaire items for reliability. The results gathered were analyzed using SPSS /PC/sup +/. Data analysis included descriptive correltional statistics such as ANOVA, Pearson Correlation Coefficient, amd chi square test. The conclusions of this analysis are summarized as follows : 1. A higher level of uncertainty was seen among parents of children with terminal cancer. 2. The first hypothesis that uncertainty in illness would differ among the three groups was supported(F=4.182, P=.020). The second and third hypotheses that mastery and coping styles would differ among the three groups were not supported. There was a correlation between uncertainty, mastery, and coping styles which was positive, also there was a positive correlation between mastery and coping style(r=.3744, P<.001) but a negative correlation between uncertainty md mastery(r=-.4749, P<.01). From the above results, it can be concluded that prediciting and controlling uncertainty in illness by considering coping styles and mastery are necessary for improved, efficient nursing interventions.

• Journal of Environmental Science International
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• v.23 no.7
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• pp.1339-1347
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• 2014

This study were performed on roadside buffer green in Songpa-dong, Songpa-gu, Seoul in order to analyze the anion concentration according to the type of composition of roadside buffer green. Buffer green separating the physical structure of the measurement points and measurement locations were separated by roadside, green interior, the other side of the road. planting density and deposit of trees per each buffer green was measured in the order of mounding type> slope type> the plain type. If the measured temperature of the location-specific weather elements roadside> inside> the other side of the road in order of measurement and the temperature is lowered farther away from the road. If the relative humidity of the road on the other side> inside> the roadside in order to measure and this is the opposite of the temperature tendency. According to physical structure reduction of the temperature on the other side of the road and roadside in order of mounding type> the plain type> slope type was measured. As a result of measuring a anion therefore concentration of the anion inside of melt is in order of mounding type> the plain type> slope type, tended to match the melt characteristics. According to measured positions anion concentration is in the order of the other side of the road> inside> the roadside was measured. As a result of correlation analysis, in the case of measurement location-specific weather and anions the temperature is positive correlation, relative humidity is negative correlation and that's results of previous studies were supported.

• Journal of Dental Rehabilitation and Applied Science
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• v.19 no.4
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• pp.291-296
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• 2003

The use of resonance frequency analysis (RFA) provides a possibility to clinically measure implant stability and osseointegration. The implant stability quotient (ISQ) value of RFA is well known that influenced by effective abutment length and stiffness of the implant in the surrounding tissues. Among these factors stiffness is not accurately defined histologically yet. And the purpose of this study was to find the histolgical relationship of RFA. 17 implants in 3 beagle dogs were used for this study. Among these implants 10 were survived for 7 months, 4 were survived for 3 months and 3 were immediate status after placement. Resonance frequency analyses were conducted and the dogs were sacrificed. Percentage of the bone to implant contact (BIC) in the interface, percentage of the mineralized bone (bone area) within the threads of the implant, and marginal bone level were measured under light microscopy. The correlation between resonance frequency and histomorphometric measurements were analysed and following results were obtained. 1. There was statistically significant correlation between ISQ value and BIC on healed implants. But ISQ value and BIC of all implants were not significantly correlated. (P<0.01) 2. Significant correlation between ISQ value and bone area was not found in this study. 3. There was statistically significant correlation between ISQ value and marginal bone level on all implants as well as on healed implants. (P<0.01).

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1271-1279
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• 2013

In this paper, a study on the prediction method of basic wind speed at the construction site of long-span bridge using short-term measurements was conducted. To determine the basic wind speed in the wind resistant design for the long-span bridge away from the weather station, statistical analysis of long-term data at site is required. Wind observation mast was installed at site, and short-term measurements were gathered and the correlation analysis between the site and the station was done using regression analysis and MCP(Measure-Correlate-Predict). The long-term wind data of the site was obtained from correlation formula after topographical revision of long-term data of the station. And basic wind speed could be estimated by extreme probability distribution analysis. The research results show that the wind speed by regression analysis is predicted lower than by MCP and after this study a series of correlation analyses at several sites will show clearly the difference two methods. And also a quality control of long-term wind data is very important in estimation of wind speed.