• Title/Summary/Keyword: 분산 방법

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MR Imaging Measurement of the Femoral Anteversional Angle as a PACS Image Viewer (MR 영상에서의 PACS Image Viewer를 이용한 대퇴골 전염각 측정)

  • Kweon, Dae-Cheol;Yang, Sung-Hwan;Park, Peom
    • Journal of radiological science and technology
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    • v.26 no.1
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    • pp.83-89
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    • 2003
  • The accurate measurement of the femoral anteversion is very important to the practice of orthopedic and osteotomy. It is measured by means of the axis of head and neck of the femur and the knee axis. At the present time, widely used computed tomography method of measuring anteversion on femoral necks of patients. Measurement by the manual method and image viewer of computed tomography to determine the anteversion of femoral head were carried out on both femurs. In September and October 2002, 5 patients 28 to 36 years of age were randomly selected from Seoul National University Hospital. The purpose of this paper was to introduce a new method to measure femoral anteversion angle utilizing PACS image viewer program in the MR imaging. Significant difference was observed between the right and left side the image viewer measurement of femoral anteversion. In conclusion, MR imaging very usefulness in the measured the angle of the femoral anteversion.

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Effect of deposition pressure on the morphology of TiO2 nanoparticles deposited on Al2O3 powders by pulsed laser deposition (펄스레이저 증착법에 의한 Al2O3 입자 표면 위 TiO2 나노입자의 코팅)

  • Choi, Bong Geun;Kim, So Yeon;Park, Cheol Woo;Park, Jae Hwa;Hong, Yoon Pyo;Shim, Kwang Bo
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.23 no.4
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    • pp.167-172
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    • 2013
  • Titanium dioxides nanoparticles coated aluminum oxide powders were fabricated by pulsed laser deposition (PLD) with Nd : YAG laser at 266 nm. The Pulse laser energy is 100 mJ/pulse. During the irradiation of the focused laser on the $TiO_2$ target, Ar gas is supplied into the chamber. The gas pressure is varied in a range of $1{\times}10^{-2}$ to 100 Pa. Titanium dioxides nanoparticles deposited aluminum oxide powders were characterized by using energy dispersive X-ray spectroscopy (EDX), high resolution transmission electron microscopy (HR-TEM), in order to understand the effect of Ar background gas on surface morphology and properties of the powders. The coated $TiO_2$ nanoparticles had nanosized spherical shape and the crystallite sizes of 10~30 nm. The morphology of coated $TiO_2$ nanoparticles is not affected by gas pressure. However, the particle size and crystallinity slightly increased with the increase of gas pressure. According to this technique, the size and crystallinity of nanoparticles can be easily controlled by controlling pressure during the laser irradiation.

New Gain Function Based on Attenuation Characteristics of Ballast Track for GPR Analysis (GPR 분석을 위한 자갈궤도 자갈의 감쇄특성을 이용한 이득함수 개발)

  • Shin, Jihoon;Choi, Yeongtae;Jang, SeungYup
    • Journal of the Korean GEO-environmental Society
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    • v.18 no.4
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    • pp.13-21
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    • 2017
  • Ballasted track has been used as track system for more than 100 years. Ballasted track has advantages of low construction cost, flexible maintenance, low noise and vibration, and so on. However, ballasted track leads to continuous settlement which causes maintenance. Recently, increase in speed, traffic volume, and weight of train requires more frequent maintenance. Fouling, well-known phenomenon of accumulation of fine materials due to intrusion of subgrade and breakage of ballast materials, expedites the settlement (i.e., irregular settlement) of track. Ground Penetrating Radar (GPR) can be one of non-destructive tools that can evaluate fouling level of ballast. In this paper, a gain function based on the attenuation characteristics of ballast material is suggested in conjunction with Hilbert transform. Lab box tests and full-scale tests indicate that the suggested method reasonably classifies clean, fouled layers, and subgrade. However, additional study to eliminate effect of sleeper and to include the scattering features of the electromagnetic wave in ballast voids should be required in order to enhance the accuracy.

Characterization of Materials for Retort Processing in Oyster Porridge (레토르트 굴죽 제조를 위한 원료의 가공적성)

  • 허성호;이호재;홍정화
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.5
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    • pp.770-774
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    • 2002
  • The effect of mixing ratio of materials and their retort processing conditions on the physical properties and preference of oyster porridge were investigated. Rice gave adequate viscosity (about 800 cp) to the porridge as it was used 10~12% level and half of it was ground. Potato starch, waxy corn starch, and Perfectamyl AC showed small variation in viscosity unrelated to the temperature, that was a good condition for high quality porridge. Especially, waxy corn starch had a good property for retort porridge because its viscosity was maintained high during the processing and decreased to preferable one after processing. Purity CSC, modified starch gave gum-like texture and didn't cause water-separation much after freezing and thawing treatment of the porridge. Therefore, it was good for enhancing the physical property of the porridge as a co-additive of waxy corn starch when it was used at quarter level of waxy corn starch. Xanthan gum increased dispersibility of materials and it was useful for stabilizing physical quality of the porridge without affecting preference when it was used below 0.2% concentration. As a result, the optimal material-mixing ratio was determined as rice 10% (50% of it was ground), waxy corn starch 1.5%, Purity CSC 0.5%, xmthan gum 0.2%, salt 0.3%, and water 87.5%. Oyster's porridge, retort processed with this recipe, showed stable physical property after 6 month storage at room temperature.

Caregivers' Knowledge, Concerns and Management of Pediatric Febrile Convulsions (아동 보호자의 열성경련에 대한 지식, 염려 및 관리)

  • Kwak, Ae Ree;Kim, Jin Sun
    • Child Health Nursing Research
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    • v.20 no.3
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    • pp.149-158
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    • 2014
  • Purpose: The purpose of this study was to investigate caregivers' knowledge, concerns, and management of children with febrile convulsions (FC). Methods: A descriptive correlation study was conducted with 133 caregivers whose children had been diagnosed with a FC. A self-administered questionnaire was used for data collection A self-administered questionnaire was used for data collection. Descriptive statistics, t-test, one-way analysis of variance and Pearson's correlation were used for data analysis. Results: The mean percent of correct answers related to knowledge was 48.5%. Many caregivers believed that FC causes brain damage and did not know that risk of subsequent epilepsy in FC is rare. Levels of concern about FC were high. Caregivers were highly concerned about further FC attacks in the night and tended to worry that Febrile children were apt to get a fever. Many caregivers used management practices which are not recommended for FC in children. There was a statistically significant negative correlation between caregivers' knowledge and concerns about FC. There was also a positive correlation between caregivers' knowledge and management of FC. Conclusion: Findings suggest that improvements are needed in caregivers' knowledge and management of FC. Caregivers' concerns related to misconception need to be addressed. Development and evaluation of educational interventions on changing caregivers' management of FC are recommended.

Flexural strength and reliability of highly translucent colored zirconia (고반투명 유색 지르코니아의 굽힘강도와 신뢰도에 대한 연구)

  • Kong, Hyun-Jun
    • Journal of Dental Rehabilitation and Applied Science
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    • v.36 no.1
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    • pp.41-47
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    • 2020
  • Purpose: The purpose of this study was to evaluate the flexural strength and reliability of highly translucent colored zirconia for all ceramic restoration. Materials and Methods: Bar-shaped specimens (25 × 4 × 2.5 mm) were prepared from highly translucent monolithic zirconia. Three experimental groups were set up according to color (shade A0, A1, and A3). For each group, 20 specimens were prepared. Flexural strength was determined using a 3-point flexural test and results were analyzed with one-way ANOVA test. Weibull statistical analysis provided 2 parameter estimates: Weibull modulus and characteristic strength. X-ray diffraction (XRD) analysis was performed. Results: There was statistically significant difference between uncolored (Shade A0) and colored (shade A1 and A3) (P < 0.05), but there was no difference between colored groups (P > 0.05). The uncolored group had higher reliability compared with colored study groups. On x-ray diffraction analysis of each group, typical peaks of tetragonal phase appeared in all groups. Conclusion: Within the limitations of this in vitro study, coloring highly translucent zirconia had significant effect on flexural strength and reliability. Therefore, clinicians should be careful when using highly translucent colored zirconia to prevent breakage of veneering ceramic and enhance aesthetics.

Bias caused by nonresponses and suggestion for increasing response rate in the telephone survey on election (전화 선거여론조사에서 무응답률 증가로 인한 편의와 응답률 제고 방안)

  • Heo, Sunyeong;Yi, Sucheol
    • Journal of the Korean Data and Information Science Society
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    • v.27 no.2
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    • pp.315-325
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    • 2016
  • Thanks to the advantages of low cost and quick results, public opinion polls on election in Korea have been generally conducted by telephone survey, even though it has critical disadvantage of low response rate. In public opinion polls on election in Korea, the general method to handle nonresponses is adjusting the survey weight to estimate parameters. This study first drives mathematical expression of estimator and its bias with variance estimators with/without nonresponses in election polls in Korea. We also investigates the nonresponse rate of telephone survey on 2012 Korea presidential election. The average response rate was barely about 14.4%. In addition, we conducted a survey in April 2014 on the respondents's attitude toward telephone surveys. In the survey, the first reason for which respondents do not answer on public opinion polls on election was "feel bothered". And the aged 20s group, the most low response group, also gave the same answer. We here suggest that survey researchers motivate survey respondents, specially younger group, to participate surveys and find methods boosting response rate such as giving incentive.

Microstructures and Electrochemical Properties of Si-M (M : Cr, Ni) as Alloy Anode for Li Secondary Batteries (리튬이차전지용 Si-M (M : Cr, Ni) 합금 음극의 미세구조와 전기화학적 특성)

  • Lee, Sung-Hyun;Sung, Jewook;Kim, Sung-Soo
    • Journal of the Korean Electrochemical Society
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    • v.18 no.2
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    • pp.68-74
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    • 2015
  • To compare the microstructure and electrochemical properties between two binary alloys (Cr-Si, Ni-Si), two composition of binary alloys with the same capacity were selected using phase-diagram and prepared by matrix-stabilization method to suppress the volume expansion of Si by inactive-matrix. Master alloys were made by Arc-melting followed by fine structured ribbon sample preparation by Rapid Solidification Process (RSP, Melt-spinning method) under the same conditions. Also powder samples were produced by wet grinding for X-Ray Diffraction (XRD) and electrochemical measurements. As predicted from the phase diagram, only active-Si and inactive-matrix ($CrSi_2$, $NiSi_2$) were detected. The results of Scanning Electron Microscope (SEM) and Transmission Electron Microscopy - Energy Dispersive X-ray Spectroscopy (TEM-EDS) show that Cr-Si alloy has finer microstructure than Ni-Si alloy, which was also predictable through phase diagram. The electrochemical properties related to microstructure were evaluated by coin type full- and half-cells. Separately, self-designed test-cells were used to measure the volume expansion of Si during reaction. Volume expansion of Cr-Si alloy electrode with finer microstructure was suppressed significantly and improved in cycle capability, in comparison Ni-Si alloy with coarse microstructure. From these, we could infer the correlation of microstructure, volume expansion and electrochemical degradation and these properties might be predicted by phase diagram.

Korea's Global Science & Technology(S&T) Agenda -A study on Internationalization of Industrial R&D for Korean SME- (한국의 글로벌 과학기술협력 연구 -한국 중소기업의 R&D 국제화 가속방안과 중소기업코디네이터-)

  • Lee, Sang-Yun;Yoon, Hong-Joo
    • The Journal of the Korea institute of electronic communication sciences
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    • v.7 no.4
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    • pp.693-705
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    • 2012
  • It is increasing the necessity of technology cooperation between nations, in the world, more and more. The international cooperation for the technology development have the dissipating effect of costs and risks and encourage efficient use of the knowledge and eventually help the firms better access overseas market easily. The S&T diplomacy of Korea is, at present, on international S&T cooperation to secure technologies to strengthen base of science, technology and innovation. This tendency is closely related with the governance issue in international S&T cooperation. And This international S&T cooperation is connected with the internationalization of firms. But it is getting more difficult for a firm, especially smaller firm like Korean SME to sustain the technological advantage over any significant period. The small and medium sized enterprises as Korean SME, internationalization of R&D is difficult just to think in terms of one framework with the limited accumulation of informations and experiences. So against that situation, this paper shows a new concept 'SME co-ordinator' as the role client(or player) reinforcing international S&T cooperation, sustaining the technological advantage for Korean SME. And 'SME co-ordinator' leads Korean SME to progress 'open innovation' not 'close innovation' as well as serving adequate information about appropriate partners and capable employer to help manage the international S&T cooperation for Internationalization of Industrial R&D for Korean SME.

A Study on Wine Selection Attributes by Wine Use Behavior - Focused on Wine Retail Shop Customers - (와인 이용 행태에 따른 와인 선택 속성에 관한 연구 - 와인 소매점 이용고객을 중심으로 -)

  • Jeon, Hyeon-Mo;Park, Mi-Young
    • Culinary science and hospitality research
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    • v.15 no.2
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    • pp.121-135
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    • 2009
  • The pattern of liquor consumers started to change as the well-being trend and great interest in health have risen for the last few years. In particular, consumption of wine is gradually increasing with the findings revealing that drinking proper amount of wine is good for preventing various adult diseases such as sclerosis of the arteries, heart disease and aging. Accordingly, this study aims at understanding the importance of wine buyers' choice attributes when buying and drinking wine in order to contribute to satisfying customers, popularizing wine and expanding its base. From December 1 to 31 in 2008, it made a survey on natives and weekly settled population living in Seoul area who had bought wine at a wine retail shop with literature and positive researches. It made an application of SPSS 12.0 to analyze the importance of wine buyers' choice attribution based on the demographical characteristics and use behavior with such analysis methods as the frequency analysis, the factor analysis, the reliability test, ANOVA and multiple regression. The results are summarized as follows. First, it showed that there are significant differences between buying and drinking wine by producing countries, buying places, prices, companions except for the number of drinking times, drinking places, and information sources. Second, it showed that wine buyers' choice attributes such as brand characteristics and effects on health have a positive effect on customer satisfaction.

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