• Magazine of the Korea Concrete Institute
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• v.9 no.4
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• pp.125-135
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• 1997

경량기포콘크리트란 시멘트슬러리 속에 미리 생성된 기포를 혼합시켜 양생시킴으써 동일한 체적의 보통콘크리트보다 가볍게 만든 콘크리트를 의미한다. 따라서 경량기포콘크리트는시멘트풀 결합재내에 기포가 무작위로 분포된 복합재료이다. 본 연구의 목적은 이러한경량기포콘크리트의 탄성계수 추정식을 미시역학적 이론을 바탕으로 추정하는데 있다. 이르 위해 본 논문에서는 미시역학적인 미분법에 Hansen의 수정기법을 적용한 수정미분법을 사용하여 경량기포콘크리트의 탄성계수 추정식을 제안하였다. 제안된 추정식을 사용하여 얻어진 결과는 실험결과와 잘 일치하였고 기존의 어떤 추정식보다도 우수한 결과를 보였다.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1987.05a
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• pp.9.2-9
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• 1987

외래에서 고막에 대한 간단한 수술을 시행함에 있어 고막의 국소 마취법으로 iontophoresis(전기 영동법)은 오래 전부터 널리 시행되어 왔으나 와우나 전정신경계에 대한 독성 때문에 논란의 대상이 되어 왔다. 1973년 Comeau이후 여러 학자에 의한 일련의 동물 및 인체 실험결과 lidocaine 의 iontophoresis는 안전하고 효과적인 방법으로 실제 임상에서의 사용을 권장하고 있으며 근년 널리 이용되고 있으나 iontophoresis를 시행함에 있어 기구 자체의 금속성 물질에 의한 독성 및 사용 약물의 내이 침투에 의한 영향에 관해서는 아직도 많은 연구가 진행되고 있다. 저자들은 1983년 부터 1986년 12월까지 고려병원 이비인후과에서 고막절개를 위해 iontophoresis에 의한 lidocaine의 국소마취법을 시행받은 환자중 무작위로 추출한 39명(46이)을 대상으로 iontophoresis시행 전후의 청력상의 변화에 관한 청각학적 고찰을 시행하여 iontophoresis후 청력 역치에 유의한 변화가 나타나지 않는다는 결과를 얻었다.

• Journal of IKEEE
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• v.16 no.1
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• pp.51-55
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• 2012

In this paper, we propose to employ a ternary sequence as a cyclic code shift keying (CCSK) modulation sequence. And we simulate the performance in a frequency hopping spread spectrum/time division multiple access (FHSS/TDMA) system with CCSK. Wireless channel is modeled as Rayleigh fading channel. From the simulation results, it is demonstrated that the system adopting the ternary sequence as a CCSK sequence has higher performance than that with a random sequence.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.12
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• pp.1355-1360
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• 2015

Recently MANET application is diversified studies on the MANET routing security and the reliable authentication mechanism is actively in progress. Stand-alone network structure of a MANET is an important field of ubiquitous computing environment of interest, Authentication techniques are already provided safety when applied to MANET reliability and efficiency in a secure authentication mechanism using the session key. However, most of the MANET environment, the model has been based on the assumption that the safety is guaranteed, When applied to an actual network situation, we can not rule out a variety of threats. This study is the testing and analysis to add the malicious node extracted at random to demonstrate the safety and efficacy of the session key certification techniques of the MANET environment.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2009.05a
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• pp.59-62
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• 2009

본 연구에서는 통행방향의 교차 상황이 발생하였을 때와 그렇지 않았을 때의 뇌파를 정량적으로 측정하여 보행자가 인지심리적 불편함을 느끼는지 여부를 알아보았다. 총 50명의 실험참가자에게 통행방향의 교차가 발생하는 영상 4개와 그렇지 않은 영상 4개를 무작위고 시청하게 하고 좌 우 전두엽, 좌 우 후두엽, 좌 우 측두엽, 중심엽 부위에서 나타나는 뇌파 신호를 추출하였다. 추출된 뇌파는 주파수 분석을 하여 alpha파 상대 스펙트럼 값, beta파 상대 스펙트럼 값, theta파 상대 스펙트럼 값을 계산하고 동선의 교차 여부에 대한 정량적 비교를 실시하였다. 실험 결과, 통행방향이 일관된 영상을 시청하였을 때 모든 부위에서 alpha파가 높게 나오는 경향을 보였다. 본 연구 결과는 통행방향이 좌/우로 교차할 때 교차하지 않는 상황에 비해 보행자가 인지심리적 더 스트레스를 느끼는 것으로 나타났다.

• Korean Journal of Poultry Science
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• v.42 no.3
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• pp.267-274
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• 2015

Peat moss has been found to be useful as a plant growth substance, fertilizer, and soil solution. It is not known, however, whether dietary peat moss affects performance in broilers. In the present study, we investigated the effects of dietary peat moss as a feed ingredient in broilers. Experimental diets were prepared by mixing basal feed with PM at 0.0, 0.2, 0.4, 0.8, and 1.6%. In experiment 1, 150 14-day-old Ross broiler chicks were housed for 2 weeks in 15 pens that were randomly assigned into five groups (0.0%, 0.2%, 0.4%, 0.8% and 1.6% PM). Dietary peat moss at 0.2% and 0.4% significantly increased the water intake, body weight, weight gain and feed efficiency compared with the control (0.0% PM, P<0.05) but did not affect feed intake. Higher levels of PM (0.8 and 1.6%) significantly decreased feed intake, body weight and weight gain. In experiment 2, 198 7-day-old Ross chicks were housed for 3 weeks in nine pens that were randomly assigned into three groups (0.0%, 0.2% and 0.4% PM). When the broilers were fed with dietary peat moss for 3 weeks, the peat moss effects disappeared. The results of the current study show that low amounts of dietary peat moss may exert beneficial effects on performance in broilers.

• Journal of the Korea Convergence Society
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• v.12 no.8
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• pp.77-83
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• 2021

The purpose of this study was to determine whether the convergence pulmonary function of the 20s men of mild intellectual disabilities with obesity to tredmill exercise. Ten subjects of mild intellectual disabilities with obesity(experimentals) and ten contrary subjects(controls) were participated in the experiment. experimental group conducted treadmill gait training and control group conducted automed exercise. Subjects were assessed for their respiratory function by using Fit mate. The result of the experiments showed high pulmonary function than the controls. Thus, it suggests that the respiratory functional data of 20s men of mild intellectual disabilities with obesity can be used as a various respiratory one for the exercise programs in the area.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.4A
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• pp.353-359
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• 2010

Cementitious matrix based composites are vulnerable to the drying shrinkage crack during the curing process. In this study, the drying shrinkage induced fracture behavior of the fiber reinforced concrete is simulated and the effects of the fiber reinforcement conditions on the fracture characteristics are analysed. The numerical model is composed of conduit elements and rigid-body-spring elements on the identical irregular lattice topology, where the drying shrinkage is presented by the coupling of nonmechanical-mechanical behaviors handled by those respective element types. Semi-discrete fiber elements are applied within the rigid-body-spring network to model the fiber reinforcement. The shrinkage parameters are calibrated through the KS F 2424 free drying shrinkage test simulation and comparison of the time-shrinkage strain curves. Next, the KS F 2595 restrained drying shrinkage test is simulated for various fiber volume fractions and the numerical model is verified by comparison of the crack initiating time with the previous experimental results. In addition, the drying shrinkage cracking phenomenon is analysed with change in the length and the surface shape of the fibers, the measurement of the maximum crack width in the numerical experiment indicates the judgement of the crack controlling effect.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.300-310
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• 2019

This study is a systematic review of randomized experimental and non-randomized studies on the effects of lavender scent therapy on pain and a meta-analysis to provide evidence-based data. The data included in the meta-analysis are 18 studies published from 2000 to 2018, with interventional subjects being surgical, maternal, arthritis and dialysis patients, and the types of interventions were massage, application, hot-pack, and taking medication. RESULTS: The effect size (Hedges' g) for pain was -0.16 [95% CI:-1.40: -0.72], which was statistically significant. The effect size according to intervention type was -1.36 [95% CI: -1.96, -0.77], local application -1.11 [95% CI:-1.57-0.66], inhalation -1.05 [95% CI:-1.54, -0.56 ], and massage -0.92 [95% CI:-1.62, -0.23], all of which were statistically significant. To explore the possible causes of heterogeneity ($I^2=88%$), meta-ANOVA was conducted with covariates of intervention type or study design, and the results revealed it was statistically insignificant (intervention type Q=0.25, df=3, p=.968, study design Q=0.22, df=1, p=.642).

• Journal of Convergence for Information Technology
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• v.10 no.7
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• pp.160-167
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• 2020

This study was conducted to investigate the effects of modified wall squat exercise after sacro-iliac joint mobilization on balance in normal adults. The total number of subjects was 34, and 17 were randomly placed in the experimental group(EG) and 15 in the control group (CG). The subjects in the EG have conducted the 3 sets of modified wall squat exercise after sacro-iliac joint mobilization per day, 3 times a week for 6 weeks and CG did not conducted the intervention. Comparing the EG's balance pre-test and post-test this study, there was a statistical significance in WDI, CD, AC and AD. In this study, it was confirmed that modified wall squat exercise after sacro-iliac joint mobilization affects balance in normal adults.