• 제목/요약/키워드: multiple measurements

검색결과 797건 처리시간 0.024초

중학생 집단따돌림 피해자의 학교적응 관련 보호요인 (Protective Factors Associated with School Adjustment of Victims in School Bullying)

  • 김동희
    • 한국보건간호학회지
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    • 제28권3호
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    • pp.633-643
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    • 2014
  • Purpose: The purpose of this study is to identify protective factors associated with school adjustment of victims in school bullying. Methods: Data were collected from 114 victims among 825 middle school students. The measurements were the self-report questionnaire on resilience, and the Childrearing Behavior Questionnaire, measurements of relationship with friends, and attitude of teachers toward bullying. Descriptive, Pearson correlation, and multiple regression analyses were used. Results: A significant relationship was observed between school adjustment of victims and resilience (r=.355, p<.01), warmth-acceptance parenting behavior (r=.482, p<.01), rejection-restriction parenting behavior (r=-.213, p<.01), and teacher's attitude toward bullying (r=.381, p<.01). The result of multiple regression analysis showed significant association of school adjustment with resilience (${\beta}$=0.247, p<.05), warmth-acceptance parenting behavior (${\beta}$=0.302, p<.001), and teacher's attitude toward bullying (${\beta}$=0.285, p<.01). Conclusion: Comprehensive interventions designed to enhance the resilience of students, improve warmth-acceptance parenting behaviors and teacher's attitude toward bullying may be helpful in promoting school adjustment of victims.

두개안면골격의 유전성에 관한 측모두부방사선 계측학적 연구 (A Cephalometric Study on the Inheritance of Craniofacial Complex)

  • 김중한;이동주
    • 대한치과교정학회지
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    • 제16권2호
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    • pp.69-80
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    • 1986
  • This study was undertaken to investigate the inheritance in craniofacial complex among Korean familial members. The subjects were 160 lateral cephalometric radiographs from 45 families. Standard product-moment correlation coefficients(r) were calculated for the measurements between the familial pairings. Further, coefficients of $determination(r^2)$ were calculated and multiple regression analyses were performed to assess the use of parents' record for predicting an offspring's craniofacial features. The following results were obtained. 1. First-degree relatives had a high level of significant correlations which were compatible with a polygenic theory of inheritance than those of non-relatives. 2. Mother-daughter pair had the highest significant correlations, then mother-son and father-son pairs, and, finally, father-daughter pair had the lowest significant correlations. 3. The genetic influence was higher in anterior cranial base length and genial angle. In contrast, the environmental influence was higher in posterior border of ramus, maxillary ant. teeth, maxillary & mandibular apical bases and Gla-P. occ. 4. The predictability of offspring's cranio-facial growth could be improved by using multiple measurements from both parents than those from father or mother only.

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발의 계측과 성인여자구두의 기본치수에 관한 연구 -경상도지역의 여대생을 중심으로- (A study on foot measurement and adult women's shoe standard size.)

  • 김효은
    • 대한가정학회지
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    • 제24권3호
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    • pp.43-50
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    • 1986
  • This study is toidentify what makes people uncomfortable when people wear new shoes and to gain fundamental data for establishing shoe sizes. Data materal from the 16 measurement investigation conducted on 796 college girl students shows the following. 1) More than 96% of the subjects have experienced footache when they wore new shoes. It is significant that 45.76% of the subjects answered shoe width, especially pump-lining part cause them to feel more pain in their feet than any other measurement elements. 2) According to multiple correlation analysis to know which parts of feet determine shoe size, both multiple correlation coefficient of feet length to other parts of foot and joint girth to other parts of foot show the highest of R=0.93. 3) According to the ANOVA-tested result of estimated function when both foot-length-joint girth and foot length-joint girth-foot width are independent variables in each case, the level of α〈0.001 is very significant. 4) The comparision between KS G3116 adult women's shoe size establishment table and my table in this study reveals that the cases of more increased joint girth measurements than standard joint girth measurements in KS G 3116 table are easy to find.

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차량 항법을 위한 지도 정합법 개발 (Development of a Map Matching Method for Land Vehicles Navigation)

  • 성태경;표종선
    • 전자공학회논문지SC
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    • 제42권4호
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    • pp.1-10
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    • 2005
  • 본 논문에서는 다중 가설 기법을 이용한 차량 항법용 지도 정합법을 제안하였다. 다중가설기법을 지도 정합에 도입하기 위하여 GPS/DR 센서 출력 부근의 도로에 대하여 의사 측정치를 정의하였으며, 이를 이용하여 단일 표적문제로 다중 가설 기법을 유도하였다. 가설에 대한 확률식을 유도할 때 GPS/DR 센서 출력뿐만 아니라 디지털 지도의 위상정보가 포함되도록 하였다. 또한 지도 정합 성능의 향상을 위하여 디지털 지도의 바이어스 오차를 보상하기 위한 바이어스 칼만 필터를 제안하였다. 주행 실험결과 제안한 지도 정합법은 도로 밀집지역, 입체도로지역 등 지도 정합이 어려운 지역에서도 우수한 성능을 보였다.

고속 3차원 측정 및 칼라 이미징을 위한 다중 광탐침 공초점 주사 현미경 (Confocal Scanning Microscopy with Multiple Optical Probes for High Speed 3D Measurements and Color Imaging)

  • 천완희;이승우;안진우;권대갑
    • 반도체디스플레이기술학회지
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    • 제7권1호
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    • pp.11-16
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    • 2008
  • Confocal scanning microscopy is a widely used technique for three dimensional measurements because it is characterized by high resolution, high SNR and depth discrimination. Generally an image is generated by moving one optical probe that satisfies the confocal condition on the specimen. Measurement speed is limited by movement speed of the optical probe; scanning speed. To improve measurement speed we increase the number of optical probes. Specimen region to scan is divided by optical probes. Multi-point information each optical probe points to can be obtained simultaneously. Therefore image acquisition speed is increased in proportion to the number of optical probes. And multiple optical probes from red, green and blue laser sources can be used for color imaging and image quality, i.e., contrast, is improved by adding color information by this way. To conclude, this technique contributes to the improvement of measurement speed and image quality.

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A system of multiple controllers for attenuating the dynamic response of multimode floor structures to human walking

  • Battista, Ronaldo C.;Varela, Wendell D.
    • Smart Structures and Systems
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    • 제23권5호
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    • pp.467-478
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    • 2019
  • Composite floor structures formed by continuous slab panels may be susceptible to excessive vibrations, even when properly designed in terms of ultimate limit state criteria. This is due to the inherent vibration characteristics of continuous floor slabs composed by precast orthotropic reinforced concrete panels supported by steel beams. These floor structures display close spaced multimode vibration frequencies and this dynamic characteristic results in a non-trivial vibration problem. Structural stiffening and/or insertion of struts between floors are the usual tentative solution applied to existing vibrating floor structures. Such structural alterations are in general expensive and unsuitable. In this paper, this vibration problem is analyzed on the basis of results obtained from experimental measurements in typical composite floors and their theoretical counterpart obtained with computational modeling simulations. A passive control system composed by multiple synchronized dynamic attenuators (MSDA) was designed and installed in these floor structures and its efficiency was evaluated both experimentally and through numerical simulations. The results obtained from experimental tests of the continuous slab panels under human walking dynamic action proved the effectiveness of this control system in reducing vibrations amplitudes.

다중 UAV에서 측정된 거리차 정보를 이용한 선형 강인 표적추적 필터 설계 (Linear Robust Target Tracking Filter Using the Range Differences Measured By Formation Flying Multiple UAVs)

  • 이혜경;한슬기;나원상
    • 전기학회논문지
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    • 제61권2호
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    • pp.284-290
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    • 2012
  • This paper addresses a new passive target tracking problem using the range differences measured by cooperative UAVs. In order to solve the range difference based passive target tracking problem within the framework of linear robust state estimation, the uncertain linear measurement model which contains the stochastic parameter uncertainty is derived by using the noisy range difference measurements. To cope with the performance degradation due to the stochastic parameter uncertainty, the recently developed non-conservative robust Kalman filtering technique [1] is applied. For the cruciform formation flying UAVs, the relationship between the target tracking performance and the measurement errors is quantitatively analyzed. The proposed filter has practical advantages over the classical nonlinear filters because, for its recursive linear structure, it can provide satisfactory convergence properties and is suitable for real-time multiple UAVs applications. Through the simulations, the usefulness of the proposed method is demonstrated.

Temperature-difference Flow Sensor Using Multiple Fiber Bragg Gratings

  • Kim, Kyunghwa;Eom, Jonghyun;Sohn, Kyungrak;Shim, Joonhwan
    • Current Optics and Photonics
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    • 제6권3호
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    • pp.297-303
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    • 2022
  • Multiple fiber Bragg gratings (FBGs) have been proposed and demonstrated for gas-flow measurements in a flow channel, using the temperature-difference method. This sensor consists of two FBG temperature sensors and two coil heaters. Coil heaters are used to heat the FBGs. The flow rate of the gas can be obtained by monitoring the difference in the Bragg-wavelength shifts of the two FBGs, which has features that exclude the effect of temperature fluctuations. In this study, experiments are conducted to measure the wavelength shift based on the flow rate, and to evaluate the gas-flow rate in a gas tube. Experimental results show that the sensor has a linear characteristic over a flow-rate range from 0 to 25 ℓ/min. The measured sensitivity of the sensor is 3.2 pm/(ℓ/min) at a coil current of 120 mA.

Operation load estimation of chain-like structures using fiber optic strain sensors

  • Derkevorkian, Armen;Pena, Francisco;Masri, Sami F.;Richards, W. Lance
    • Smart Structures and Systems
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    • 제20권3호
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    • pp.385-396
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    • 2017
  • The recent advancements in sensing technologies allow us to record measurements from target structures at multiple locations and with relatively high spatial resolution. Such measurements can be used to develop data-driven methodologies for condition assessment, control, and health monitoring of target structures. One of the state-of-the-art technologies, Fiber Optic Strain Sensors (FOSS), is developed at NASA Armstrong Flight Research Center, and is based on Fiber Bragg Grating (FBG) sensors. These strain sensors are accurate, lightweight, and can provide almost continuous strain-field measurements along the length of the fiber. The strain measurements can then be used for real-time shape-sensing and operational load-estimation of complex structural systems. While several works have demonstrated the successful implementation of FOSS on large-scale real-life aerospace structures (i.e., airplane wings), there is paucity of studies in the literature that have investigated the potential of extending the application of FOSS into civil structures (e.g., tall buildings, bridges, etc.). This work assesses the feasibility of using FOSS to predict operational loads (e.g., wind loads) on chain-like structures. A thorough investigation is performed using analytical, computational, and experimental models of a 4-story steel building test specimen, developed at the University of Southern California. This study provides guidelines on the implementation of the FOSS technology on building-like structures, addresses the associated technical challenges, and suggests potential modifications to a load-estimation algorithm, to achieve a robust methodology for predicting operational loads using strain-field measurements.

Evaluation of the accuracy of linear and angular measurements on panoramic radiographs taken at different positions

  • Nikneshan, Sima;Sharafi, Mohamad;Emadi, Naghmeh
    • Imaging Science in Dentistry
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    • 제43권3호
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    • pp.191-196
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    • 2013
  • Purpose: This study assessed the accuracy of linear and angular measurements on panoramic radiographs taken at different positions in vitro. Materials and Methods: Two acrylic models were fabricated from a cast with normal occlusion. Straight and $75^{\circ}$ mesially and lingually angulated pins were placed, and standardized panoramic radiographs were taken at standard position, at an $8^{\circ}$ downward tilt of the occlusal plane compared to the standard position, at an $8^{\circ}$ upward tilt of the anterior occlusal plane, and at a $10^{\circ}$ downward tilt of the right and left sides of the model. On the radiographs, the length of the pins above (crown) and below (root) the occlusal plane, total pin length, crown-to-root ratio, and angulation of pins relative to the occlusal plane were calculated. The data were subjected to repeated measures ANOVA and LSD multiple comparisons tests. Results: Significant differences were noted between the radiographic measurements and true values in different positions on both models with linear (P<0.001) and those with angulated pins (P<0.005). No statistically significant differences were observed between the angular measurements and baselines of the natural head posture at different positions for the linear and angulated pins. Conclusion: Angular measurements on panoramic radiographs were sufficiently accurate and changes in the position of the occlusal plane equal to or less than $10^{\circ}$ had no significant effect on them. Some variations could exist in the pin positioning (head positioning), and they were tolerable while taking panoramic radiographs. Linear measurements showed the least errors in the standard position and $8^{\circ}$ upward tilt of the anterior part of the occlusal plane compared to other positions.