• Title/Summary/Keyword: 사이중심도

Search Result 2,954, Processing Time 0.032 seconds

Characterization of Surfaces by Contact Angle Goniometry - I. Contact Angle Measurement by Laser Beam Projection- (접촉각측정에 의한 표면의 특성연구 - I. 레이저광선 투영에 의한 접촉각의 측정방법-)

  • Park Chung Hee
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.15 no.1
    • /
    • pp.70-75
    • /
    • 1991
  • Contact angle measuring device was developed in this laboratory using laser beam projec-tion. The new method allows for rapid and direct determination of stationary, advancing, and receding contact angles on both planar and nonplanar solid surfaces, including fibers with very small diameters. A narrow laser beam impinges on an edge of an interface of liquid and solid. This makes two projected laser beam lines upon and radiating from the center of a protractor scale on a tangent screen. Contact angle is measured by determining the difference in angle on the protractor scale between the two projected laser beam lines. Contact angles measured on Perspex-CQ using this instrument were in agreement with the literature. it was shown that this instrument provides a novel method for the facile and accurate measurement of contact angles.

  • PDF

Construction of Framework for Metadata Integration Using Master Data Approach (마스터 데이터를 활용한 메타데이터 통합 프레임워크 구축)

  • Lee, Seungmin
    • Journal of Korean Library and Information Science Society
    • /
    • v.44 no.1
    • /
    • pp.201-225
    • /
    • 2013
  • In order to overcome the problems of current approaches to metadata interoperability based on element mapping, this research proposed Master Element Framework that is an alternative approach to metadata interoperability. It is an approach to integrate metadata elements that have the same value, instead of direct mapping between similar elements. Master Element Framework is constructed to semantically integrate metadata elements in a hierarchical order and to interconnect between heterogeneous metadata standards. This approach is expected to be an alternative approach to metadata interoperability.

Developing the Automatic Measurement System of Tree's Vigor based on Ubiquitous Sensor Network (유비쿼터스 센서 네트워크를 이용한 자동 수목 활력도 측정 시스템 개발)

  • Sim, Kyu-Won;Jeon, Mun-Jang;Kim, Jung-Gyu
    • Journal of Korea Society of Industrial Information Systems
    • /
    • v.12 no.1
    • /
    • pp.61-71
    • /
    • 2007
  • The main purpose of this study was to develop Automatic Measurement System for monitoring tree's vigor using Ubiquitous Sensor Network This study also focused on presenting an alternative for monitoring automatically tree's vigor due to Shigometer's limits. Application test of the system in comparison with Shigometer showed that the measurement values were not different to choose between the two, and battery lasted about 1,844 days in this system. To test the sensor network the possible transmission distance using the sensor network in maximum was 130m. Investigation and management expenses can be reduced and labor productivity will also be improved in the forest and street trees.

  • PDF

Characteristics of Sham/Placebo Acupuncture Controlled Trials for Headache (두통에 대한 Sham/Placebo 침술 대조군 연구의 특성에 대한 연구)

  • Jung, Su-Hyung;Seo, Jung-Chul;Yang, Angela;Xue, Charlie
    • Journal of Acupuncture Research
    • /
    • v.26 no.1
    • /
    • pp.99-109
    • /
    • 2009
  • 목적 : 두통의 침술효과에 대한 연구가 꾸준히 이루어지고 있다. 하지만 많은 연구들에서 서로 상충되는 결과를 내놓고 있다. 이에 저자는 대조군 집단 시술의 역할과 시험의 특성에 대해 연구하는 데 있어 몇 가지 유형의 두통, 특히 긴장성 두통(Tension-type headache, TTH)과 편두통에 대한 침술의 대조군 시험에서 나타나는 일관성 없는 발견 사항들의 원인이 무엇인지에 대해 밝히려고 하였다. 방법 : 두통의 침술효과에 대해 보고하고 있는 11개의 임의대조군 시험(Randomized controlled trials, RCTs)을 대상으로 하여 위약 침술과 방법론적 특성 범주 III과 IV를 중심으로 위약 시술 분석, 비교를 실시하였다. 결과 : 임상적 유효성과의 상관관계에 있어 범주 III과 IV 사이에는 유의한 차이가 없었다. 표본 크기 계산, 표본 전체 크기, 진짜 집단과 위약 집단에 속한 피험자의 수에는 긍정적 결과와 중립적 결과 사이에 유의한 차이가 없었다. 결론 : 두통의 임의대조군 시험에 대한 다양한 유형의 위약 대조군과 침술의 방법론적 특성이 임상적 효과를 예측해 주는지의 여부에 대해 추가 연구가 이루어져야 하겠다.

  • PDF

The Influence of the Number of Electrodes, the Position and Direction of a Single Dipole on the Relation Between S/N ratio and EEG Dipole Source Estimation Errors (뇌전위의 단일 쌍극자 모델에서 전극의 개수, 쌍극자의 위치 및 방향이 S/N과 쌍극자 추정 오차사이의 관계에 미치는 영향에 관한 시뮬레이션 연구)

  • 김동우;배병훈
    • Journal of Biomedical Engineering Research
    • /
    • v.15 no.1
    • /
    • pp.71-76
    • /
    • 1994
  • In the source localization using single dipole model, the influence of the number of electrodes, the position and direction of a single dipole on the relation between S/W ratio and dipole parameter estimation errors is important. Monte Carlo simulation was used to investigate this influence. The forward problem was calculated using three spherical shell model, and dipole parameters were optimized by means of simplex method. As the number of electrodes became large, as the dipole went from midbrain to cortex, and as the direction of dipole changed from radial to tangential, the average and standard deviation of estimation errors became small.

  • PDF

An Experimental Phonetic Study on the Duration of the Korean Nasal Sound - With Reference to the Successive Coupling from Syllable final to Initial in a Word - (한국어 비음(nasal sound)의 지속시간에 관한 실험음성학적 연구 - 낱말내에서 음절말과 음절초로 연속결합하는 경우와 관련하여 -)

  • 성철재
    • The Journal of the Acoustical Society of Korea
    • /
    • v.19 no.6
    • /
    • pp.28-33
    • /
    • 2000
  • This paper investigates the durational difference between syllable final segment and syllable initial one within word level. The Korean consonant (m) and (nn) were focused mainly. It could hardly say that there was significant difference between preceding consonant and following one, but it was observed that the preceding consonant tended to be shorter than the following one in the (mm) case. This might be explained by the fact that bilabial sound should appear at the first step of language acquisition. This leads to the conclusion that the articulation of preceding (m) shall be easier than others. In the case of alveolar geminate (nn), there was considerable statistic difference between preceding and following segments. It tends to be that the preceding consonant has longer duration.

  • PDF

Liability of Tort Related to Private Security in America (미국의 민간경비관련 불법행위 책임)

  • Choi, Sun-Woo
    • The Journal of the Korea Contents Association
    • /
    • v.8 no.1
    • /
    • pp.39-47
    • /
    • 2008
  • These days American private security industries has rapidly grown, and its scales(employment, expenditures) exceed the public police. American private security are based on the theories such as privatization, co-production, and build more developmental framework. But the behind of private security, its civil and criminal liabilities are more issued. In this, among the civil liabilities focused on the tort liability. In civil liabilities, contract liability is specially raised by between contractors, on the other hand tort liability is raised in general without special relationship in civil law relations. In this study, I would observe the types, conditions, protest reasons and the cases in tort generated by private security officials.

Improving Polynomial Regression Using Principal Components Regression With the Example of the Numerical Inversion of Probability Generating Function (주성분회귀분석을 활용한 다항회귀분석 성능개선: PGF 수치역변환 사례를 중심으로)

  • Yang, Won Seok;Park, Hyun-Min
    • The Journal of the Korea Contents Association
    • /
    • v.15 no.1
    • /
    • pp.475-481
    • /
    • 2015
  • We use polynomial regression instead of linear regression if there is a nonlinear relation between a dependent variable and independent variables in a regression analysis. The performance of polynomial regression, however, may deteriorate because of the correlation caused by the power terms of independent variables. We present a polynomial regression model for the numerical inversion of PGF and show that polynomial regression results in the deterioration of the estimation of the coefficients. We apply principal components regression to the polynomial regression model and show that principal components regression dramatically improves the performance of the parameter estimation.

A Study on the Curriculums of Data Science (데이터 사이언스 교과과정에 대한 연구)

  • Yi, Myongho
    • Journal of the Korean BIBLIA Society for library and Information Science
    • /
    • v.27 no.1
    • /
    • pp.263-290
    • /
    • 2016
  • The purpose of this study is to compare seven data science programs in Korea and ten data science programs in the US. Results show that 14 data science programs are housed in graduate schools. 10% of data science courses in Korea and 26% in the US fall under the Math and Statistics Knowledge area, one of the three areas defined by Conway. The syllabus analysis does not show much differences in terms of class contents and grading. The results of this study can be used to design data science programs that are more effective and well-grounded.

The Comparative Study on Safety Factors at Elevator Management System Operation (승강기 관리시스템 운영 시 안전요소에 관한 비교연구)

  • Park, Joo-Bong;Shin, Seung-Jung
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.14 no.6
    • /
    • pp.159-162
    • /
    • 2014
  • Recently, from 2008 to 2012, there are many of elevator safety patents from patent office survey. In this paper, we analyzed the elevator safety patent from 2009 to 2013, found out safety factor is safety control, emergency stop equipment and door opening equipment. Through reliability statistics, we defined the most important things for safety elevator factor is this three things, studied the reason about many patents. Finally, we propose the Kinect Scada elevator system for prevention safety accident.