• 한국콘텐츠학회논문지
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• 제22권9호
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• pp.439-450
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• 2022

연구 목적: 가임 여성의 조기진통에 대한 예방적 자가관리 지식(PSMK-PL) 측정도구를 개발하는 것이다. 연구 방법: 연구절차는 1단계 개념 정의(문헌 고찰, 질적 면담), 2단계 문항개발(문항작성, 전문가 내용타당도, 가임 여성의 인지적 면담), 3단계 내용타당도와 신뢰도 검정(250명의 온라인 설문조사 자료 분석)이었다. 문항반응이론을 적용한 내용타당도는 2-모수 로지스틱 모형을 사용하였다. 내적일관성 신뢰도는 Cronbach's α (95% CI)를 확인하였다. 연구 결과: 전문가 내용타당도 검정과 인지적 인터뷰를 통해 수정한 예비 문항 30개 중 적합도, 양류상관계수, 중요도를 고려해 6개를 삭제하였다. 최종 24문항, 하부 범주는 조기진통의 위험요인(10개), 예방적 관리(8개), 조기진통의 증상과 증상관리(6개)였다. 최종 문항 난이도(-2.18~0.90), 변별도(0.80~2.90), 내적합도(0.78~1.14), 양류상관계수(0.42~0.68)는 모두 수용할 만한 수준이었다. Cronbach's α (95% CI)는 .89(.87~.91)였다. 결론: PSMK-PL 측정도구는 가임 여성의 조기진통에 대한 예방적 자가관리지식을 측정할 수 있는 검정된 척도이다.

• Structural Engineering and Mechanics
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• 제66권4호
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• pp.531-542
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• 2018

In this paper an analytical model in a closed form able to reproduce the monotonic flexural response of external RC beam-column joints with smooth rebars is presented. The column is subjected to a constant vertical load and the beam to a monotonically increasing lateral force applied at the tip. The model is based on the flexural behavior of the beam and the column determined adopting a concentrated plasticity hinge model including slippage of the main reinforcing bars of the beam. A simplified bilinear moment-axial force domain is assumed to derive the ultimate moment associated with the design axial force. For the joint, a simple truss model is adopted to predict shear strength and panel distortion. Experimental data recently given in the literature referring to the load-deflection response of external RC joints with smooth rebars are utilized to validate the model, showing good agreement. Finally, the proposed model can be considered a useful instrument for preliminary static verification of existing external RC beam-column joints with smooth rebars for both strength and ductility verification.

• 한국의학물리학회지:의학물리
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• 제15권3호
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• pp.128-133
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• 2004

기능적 자기공명영상을 이용하여 진동자의 자극에 따른 감각 피질의 반응에 대하여 연구하였다 주로 40 Hz 이하의 주파수에 반응하는 촉각소체의 혈류반응을 조사하기 위하여 8, 15, 그리고 25 Hz의 주파수를 사용하였다. 사용되고 있는 진동자의 한계를 극복한 공기의 압력을 이용하여 진동할 수 있는 진동자를 특수 제작하였다. 예측한 바와 같이 감각 피질의 촉각소체 부위가 주파수에 따라 반응하는 모습을 볼 수 있었다. 주파수 대 반응 면적을 각 pixel의 개수와 signal percent change로 분석하여 주파수가 증가할수록 signal percent change의 분포는 넓어지고 더 많은 pixel들이 반응한다는 것을 알 수 있었다.

• 전기학회논문지
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• 제65권6호
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• pp.911-917
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• 2016

DC-based power system is paid attention as interests in energy efficiency and power quality are increased. However, standardization and researches for commercializing Low Voltage DC(LVDC) distribution system are still insufficient. Protection system, which is closely related with reliability, power quality, safety, and life expectancy of components in power system, is also included. This paper therefore analyzes fault response characteristics in LVDC distribution system as a preliminary study on protection schemes. A stepwise analysis on fault current from both AC/DC converter and DC/DC converter is performed and related expressions are derived. And then, modeling and simulation with various conditions are conducted by using ElectroMagnetic Transients Program (EMTP) to verify analysis results. Based on research results in the paper, direction for development of protection schemes for LVDC distribution system is suggested.

• Food Science and Biotechnology
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• 제18권2호
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• pp.494-499
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• 2009

To improve phenylalanine ammonia lyase (E.C.4.3.1.5-PAL) activity in recombinant Escherichia coli, Some approaches for improving phenylalanine ammonia lyase (PAL) activity in recombinant E. coli were developed following preliminary studies by means of response surface method. The results shown that permeabilization with combination of Triton X-100, cetyl trimethyl ammonium bromide (CTAB), and acetone enriched cellular recombinant PAL activity significantly, which improved over 10-fold as compared with the control (untreat cell), as high as 181.37 U/g. The optimum values for the tested variables were Triton X-100 0.108 g/L, CTAB 0.15 g/L, and acetone 45.2%(v/v). Furthermore, a second-order model equation was suggested and then validated experimentally. It was indicated that addition of surfactants and organic solvents made the cells more permeable and therefore allowed easier access of the substrate to the enzyme and excretion of the product, which increased the rate of transport of L-phenylalanine and trans-cinnamic acids. These improved methods of PAL activity enrichment could serve as a rich enzyme source, especially in the biosynthesis of L-phenylalanine.

• 한국기계가공학회지
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• 제13권4호
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• pp.56-68
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• 2014

This paper presents an experiment on the modeling, analysis, prediction and optimization of machining parameters used during the turning process of the low-carbon steel known as ST40. The parameters used to develop the model are the cutting speed, the feed rate, and the depth of the cut. The experiments were carried out under various conditions, with three level of parameters and two different treatments for each level (with and without a lubricant), to determine the effects of the parameters on the surface roughness and electric current consumption. These effects were investigated using response surface methodology (RSM). A second-order model is used to predict the values of the surface roughness and the electric current consumption from the results of experiments which collected preliminary data. The results of the experiment and the predictions of the surface roughness and electric current consumption under both treatments were found to be nearly identical. This result shows that the feed rate is the main factor that influences the surface roughness and electric current consumption.

• Nuclear Engineering and Technology
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• 제54권7호
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• pp.2529-2539
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• 2022

Stochastic and an empirical Green's function (EGF) methods are preliminarily applied to simulate strong ground motions (SGMs) at seismic stations within nuclear power plant (NPP) sites in South Korea by an assumed large earthquake with M_W6.5 (scenario earthquake) on the causative fault of the 2016 Gyeongju earthquake with M_W5.5 (mainshock). In the stochastic method, a ratio of spectral amplitudes of observed and simulated waveforms for the mainshock is assumed to be an adjustment factor. In the EGF method, SGMs by the mainshock are simulated assuming SGMs by the 2016 Gyeongju earthquake with M_W5.0 (foreshock) as the EGF. To simulate SGMs by the scenario earthquake, a ratio of fault length to width is assumed to be 2:1 in the stochastic method, and SGMs by the mainshock are assumed to be EGF in the EGF method. The results are similar based on a bias of the simulated response spectra by the two methods, and the simulated response spectra by the two methods exceeded commonly standard design response spectra anchored at 0.3 g of NPP sites slightly at a frequency band above 4 Hz, but considerable attention to interpretation is required since it is an indirect comparison.

• Structural Engineering and Mechanics
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• 제32권5호
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• pp.587-608
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• 2009

Modern earthquake-resistant design aims to isolate architectural precast concrete panels from the structural system so as to reduce the interaction with the supporting structure and hence minimize damage. The present study seeks to maximize the cladding-structure interaction by developing an energy-dissipating cladding system (EDCS) that is capable of functioning both as a structural brace, as well as a source of energy dissipation. The EDCS is designed to provide added stiffness and damping to buildings with steel moment resisting frames with the goal of favorably modifying the building response to earthquake-induced forces without demanding any inelastic action and ductility from the basic lateral force resisting system. Because many modern building facades typically have continuous and large openings on top of the precast cladding panels at each floor level for window system, the present study focuses on spandrel type precast concrete cladding panel. The preliminary design of the EDCS was based on existing guidelines and research data on architectural precast concrete cladding and supplemental energy dissipation devices. For the component-level study, the preliminary design was validated and further refined based on the results of nonlinear finite element analyses. The stiffness and strength characteristics of the EDCS were established from a series of nonlinear finite element analyses and are discussed in detail in this paper.

• 대한간호학회지
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• 제27권4호
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• pp.753-764
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• 1997

This study was conducted to develop a sexual satisfaction tool for married women in Korea. The data was collected from July 19 to Aug 18, 1997 by means of questionnaires developed by researchers. The subject were 417 married women living in Seoul and Pusan. The process of this study was as follows : 1) The concept of sexual satisfaction was defined. 2) A conceptual framework was identified based on the extensive review of relevant literature and interviews with married women. 3) The preliminary question items containing the attributes and elements of the concept of sexual satisfaction were listed. 4) The preliminary items were revised after a pilot study. 5) The Index of Content Validity(CVI) was calculated from the content specialists' rating. 6) The reliability and validity of the sexual satisfaction measurement tool were tested. As a result of the item and factor analysis, 17 out of 30 items were found to be valid, consequently could be used to measure sexual satisfaction for married women. These final 17 items were divided into two factors. These factors were labeled as "situation factor" (10 items) and "response factor"(7 items) according to the attributes of the clustered items. The reliability of the final 17 items was .9118. Further research is needed to confirm the reliability and validity of the tool by applying it to a group of healthy married women and to a group of married women having health-related problem.

• Structural Engineering and Mechanics
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• 제49권3호
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• pp.395-410
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• 2014

Fiber Reinforced Elastomeric Bearings (FREBs) are a relatively new type of laminated bearings that can be used as seismic/vibration isolators or bridge bearings. In an unbonded (U)-FREB, the bearing is placed between the top and bottom supports with no bonding or fastening provided at its contact surfaces. Under shear loads the top and bottom faces of a U-FREB roll off the contact supports and the bearing exhibits rollover deformation. As a result of rollover deformation, the horizontal response characteristics of U-FREBs are significantly different than conventional elastomeric bearings that are employed in bonded application. Current literature lacks an efficient analytical horizontal stiffness solution for this type of bearings. This paper presents two simplified analytical models for horizontal stiffness evaluation of U-FREBs. Both models assume that the resistance to shear loads is only provided by an effective region of the bearing that sustains significant shear strains. The presented models are different in the way they relate this effective region to the horizontal bearing displacements. In comparison with experimental results and finite element analyses, the analytical models that are presented in this paper are found to be sufficiently accurate to be used in the preliminary design of U-FREBs.