• 한국군사과학기술학회지
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• 제9권4호
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• pp.71-80
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• 2006

Strapdown Inertial navigation systems consist of an inertial sensor assembly(ISA), electronic modules to process sensor data, and a navigation computer to calculate attitude, velocity and position. In the ISA, most gryoscopes such as RLGs and FOGs, have digital output, but typical accelerometers use current as an analog output. For a high precision inertial navigation system, sufficient stability and resolution of the accelerometer board converting the analog accelerometer output into digital data needs to be guaranteed. To achieve this precision, the asymmetric error and A/D reset scale error of the accelerometer board must be properly compensated. If the relation between the acceleration error and the errors of boards are exactly known, the compensation and estimation techniques for the errors may be well developed. However, the A/D Reset scale error consists of a pulse-train type term with a period inversely proportional to an input acceleration additional to a proportional term, which makes it difficult to estimate. In this paper, the effects on the acceleration output for auto-pilot situations and the effects of A/D reset scale errors during horizontal alignment are qualitatively analyzed. The result can be applied to the development of the real-time compensation technique for A/D reset scale error and the derivation of the design parameters for accelerometer board.

• 한국ITS학회 논문지
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• 제18권6호
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• pp.76-95
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• 2019

자중계는 화물차 운전자들이 자신의 화물무게를 인지하지 못해서 생기는 부득이한 과적을 방지하기 위해서 반드시 필요한 기술이다. 본 연구에서는 자중계의 일본의 의무장착 사례와 국내 활용현황에 대하여 조사하고 자중계와 GPS, 모뎀을 연동한 IoT 관제시스템을 시험차량에 설치한 후 원격 모니터링을 통해 과적운행패턴을 규명하고, 자중계 설치 시 과적 예방효과와 운송 효율성에 대하여 분석하고자 하였다. 장기 모니터링 데이터를 분석한 결과, 자중계 설치 후 운전자가 화물중량을 인지함으로써 과적율과 과적 중량이 감소되는 효과를 확인하였으며, 건설기계 차량의 경우 운송거리 단축에 의한 운송효율이 높아지는 결과를 확인하였다. 또한 단속지점의 GPS 좌표와 화물차량의 이동경로를 매칭하여 과적상태인 경우 회피 운행경로를 분석하였으며, 적재물의 종류에 따른 운행거리와 적재중량을 분석하였다.

• 천문학회보
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• 제38권1호
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• pp.32.2-32.2
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• 2013

We examine large-scale environmental effects on the formation and the mass growth of dark matter halos. To facilitate this, we constructed dark matter halo merger trees from a cosmological N-body simulation, which enabled us to trace the merger information and the assembly history of individual halos. In fact, since the massive halos are more likely to be distributed in denser regions than in less dense regions (Mo & White, 1996), the large-scale environment dependence of the properties of halos can be partly originated from the halo mass effect. In order to avoid such contamination, caused by the mass dependence of halo properties, we carefully measured the local overdensity as the indicator of large-scale environment, which was calculated to be as independent of halo mass as possible. Small halos (${\sim}10^{11-12}M_{\odot}$), which usually host isolated single galaxies, show a notable difference on the formation time of galaxies depending on their large-scale environments, which reconfirms halo assembly bias (Gao & White, 2007). Furthermore, we investigate how this environmental effect on small halos is correlated with the mass assembly history of galaxies by using our semi-analytic model. We found that assembly bias in small halos does not have significant effects on the formation time or on the star formation history of galaxies residing in those halos except for the individual stellar mass of galaxies at z = 0. On average, isolated galaxies in high-density regions tend to be slightly more massive than those in low-density regions. Although the observational data from the current galaxy surveys is not yet sufficient for testing this prediction, future galaxy surveys will be able to explore these small galaxies more thoroughly.

• 교육녹색환경연구
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• 제15권1호
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• pp.40-48
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• 2016

본 연구는 적정규모학교의 효율적인 육성을 위하여, 적정규모학교에 대한 이론적 고찰, 국내 학생수 및 학교현황 분석, 적정규모학교 육성사업 현황분석, 적정규모학교 가이드라인(안) 제안 등의 순서로 연구를 진행하였다. 적정규모학교 기준(안)은 시 도별 특성과 지역의 여건을 고려하며, 기존 선행연구들의 교육적 효과와 교육과정의 운영 효율성을 고려하여 이상적인 방향으로 제안하고자 한다. 본 연구에서는 적정규모학교의 효율적인 육성을 위하여, 적정규모학교에 대한 이론적 고찰, 국내 학생수 및 학교현황 분석, 적정규모학교 육성사업 현황분석을 통해 적정규모학교 가이드라인(안)을 제안하였다.

• 동서간호학연구지
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• 제24권1호
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• pp.44-51
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• 2018

Purpose: The purpose of this study was to examine the actor and partner effects of self efficacy, marital adjustment and family support on Yangseang in infertile couples using the actor-partner interdependence model. Methods: The participants were 108 infertile couples. Data were collected using the Yangsaeng Scale, Infertility Self Efficacy Scale, Revised Dyadic Adjustment Scale, and Perceived Social Support Scale from March to April in 2016. The Actor-Partner Interdependence Model was used to analyze the actor and partner effects of self-efficacy, marital adjustment and family support on Yangsaeng. Results: The fit indices for the model were Comparative Fit Index (CFI) = 0.99, Normed Fit Index (NFI) = 0.99, Tucker-Lewis Index (TLI) = 0.90, and Root Mean Square Error of Approximation (RMSEA) = 0.01, which met the criteria. We found that only self efficacy had an actor effect on Yangsaeng. Marital adjustment and family support of infertile husbands had an actor effect on the Yangsaeng. In addition, marital adjustment showed an interaction effect. Conclusions: The findings of this study indicate that the level of Yangseang in infertile couples was positively associated with the levels of self efficacy and martial adjustment. Partner effects may be hidden due to much stronger actor effects on Yangseang.

• Wind and Structures
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• 제12권2호
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• pp.151-177
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• 2009

The International Hurricane Research Center (IHRC) at Florida International University (FIU) is pursuing research to better understand hurricane-induced effects on residential buildings and other structures through full-scale aerodynamic and destructive testing. The full-scale 6-fan Wall of Wind (WoW) testing apparatus, measuring 4.9 m tall by 7.3 m wide, is capable of generating hurricane-force winds. To achieve windstorm simulation capabilities it is necessary to reproduce mean and turbulence characteristics of hurricane wind flows. Without devices and methods developed to achieve target wind flows, the full-scale WoW simulations were found to be unsatisfactory. To develop such devices and methods efficiently, a small-scale (1:8) model of the WoW was built, for which simulation devices were easier and faster to install and change, and running costs were greatly reduced. The application of such devices, and the use of quasiperiodic fluctuating waveforms to run the WoW fan engines, were found to greatly influence and improve the turbulence characteristics of the 1:8 scale WoW flow. Reasonable reproductions of wind flows with specified characteristics were then achieved by applying to the full-scale WoW the devices and methods found to be effective for the 1:8 scale WoW model.

• 한국태양에너지학회 논문집
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• 제27권3호
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• pp.135-142
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• 2007

The model to predict flow duration characteristics and performance for small scale hydro power(SSHP) plants is studied to analyze the effects of rainfall condition. One existing SSHP plant was selected and performance characteristics was analyzed by using the developed model. The predicted results from the model developed show that the data were in good agreement with operational results of existing SSHP plant. The results show that both the scale parameter and the shape parameter have large effects on the performance of SSHP sites. And also it was found that the model developed in this study can be a useful tool to predict the performance of SSHP sites.

• Advances in nano research
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• 제5권1호
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• pp.1-12
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• 2017

In this paper, the critical buckling temperature of single-walled Boron Nitride nanotube (SWBNNT) is estimated using a new nonlocal first-order shear deformation beam theory. The present model is capable of capturing both small scale effect and transverse shear deformation effects of SWBNNT and is based on assumption that the inplane and transverse displacements consist of bending and shear components, in which the bending components do not contribute toward shear forces and, likewise, the shear components do not contribute toward bending moments. Results indicate the importance of the small scale effects in the thermal buckling analysis of Boron Nitride nanotube.

• 한국컴퓨터정보학회논문지
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• 제21권10호
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• pp.85-89
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• 2016

This study investigated the effects of nonviolent communication(NVC) program consisted of communication competency, relationship and anger in 48 nurses. Data were collected by Choe(2004)'s Communication Competency Scale, Ju(2005)'s Relationship Scale and anger of Visual Analogue Scale. Statistic analysis consisted of average, standard deviation, minimum and maximum, paired t-test using SPSS 21 program were done. After NVC program, nurses's communication competency(p=.000) and relation (p=.000) were improved. Nurse's anger was lowered(p=.000). The results will provide the basic data to develop the Mini-NVC programs for various work fields as like ER, ICU nurses and will provide the evidences for safe and non-violent work environment and more related studies.

• Advances in materials Research
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• 제7권1호
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• pp.1-16
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• 2018

Thermal bifurcation buckling behavior of fully clamped Euler-Bernoulli nanobeam built of a through thickness functionally graded material is explored for the first time in the present paper. The variation of material properties of the FG nanobeam are graded along the thickness by a power-law form. Temperature dependency of the material constituents is also taken into consideration. Eringen's nonlocal elasticity model is employed to define the small-scale effects and long-range connections between the particles. The stability equations of the thermally induced FG nanobeam are derived via the principal of the minimum total potential energy and solved analytically for clamped boundary conditions, which lead for more accurate results. Moreover, the obtained buckling loads of FG nanobeam are validated with those existing works. Parametric studies are performed to examine the influences of various parameters such as power-law exponent, small scale effects and beam thickness on the critical thermal buckling load of the temperature-dependent FG nanobeams.