• International Journal of Contents
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• 제18권1호
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• pp.76-84
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• 2022

Tidal power generation plays a critical role in reducing greenhouse gas emissions. It uses a tidal force generated by gravitational force between the moon, the earth, and the sun. The change of seawater height generates the tide-generating force, and the magnitude of the change is the tide level. The tide level change has the same period as the tide-generating force twice a day, every 29.5 days, every year, and every 18.6 years. Sihwa Lake Tidal Power Station is Korea's first tidal power plant that began commercial power generation in August 2011 and has been accumulating a large volume of data on electricity production, power generation sales, sluice displacement, and tide levels. The purpose of this paper was to analyze the impact of the inefficiency factors affecting production and the tidal level change on tidal power generation and their characteristics using Sihwa Lake Tidal Power's operational performance data. Throughout this paper we show that tidal power generating operation is accurately predicting the trends of magnitude of tidal force to be periodical for each day. determining the drop to initiate the water turbine generator factoring the constraints on the operation of Sihwa Lake, and reflecting the water discharge through the floodgate and water turbine during the standby mode in the power generation plan to be in the optimal condition until the initiation of the next power generation can maximize power generation.

• 수산해양기술연구
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• 제19권1호
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• pp.33-39
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• 1983

폐쇄적인 지형구조를 보이는 여자만에서 환경조사 및 어장관리를 위한 해양물리학적 기초자료를 얻기 위하여, 1982년 10월 30일부터 11월 6일까지 만구에서 실시한 측류판추적 및 유속계에 의한 측류자료를 사용하여 해수교류 및 교환량을 추정하고 그 해수교환특성을 알아보았다. 여자만의 평균용적(1.96km super(3))에 대하여 유입량은 43%(조차, 320cm), 유출량은 42%(조차, 304cm)였다. 이로부터 얻은 항류성분은 약 3.7$\times$10 super(7)m super(3)로서 대부분이 담수유출량으로 해석된다. 물질수송에 기여한다고 생각되는 평균해수교환량은 만의 용적(2.33km super(3); 평균고조면 3.1m 기준)에 대하여 썰물 때 1.97$\times$10 super(6) cm super(2)/sec, 밀물 때 1.69$\times$10 super(6) cm super(2)/sec였다. 썰물 때 확산계수가 큰 것은 교환능률이 컸음에 기인하여, 썰물 때 shear분산효과가 크다고 생각된다.

• 한국화재소방학회논문지
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• 제28권6호
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• pp.76-81
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• 2014

이 연구는 RespiTrainer를 활용한 백밸브마스크 환기에서 1인 백밸브마스크, 2인 백밸브마스크, 전문기도삽관 별 호흡량과 기도압을 비교 분석하였다. 실험기간은 2014년 6월 2일부터 6월 10일까지이며, 수집된 자료는 SPSS 18.0을 이용하여 분석하였다. 그 결과 기관내삽관을 통한 환기 $497{\pm}78mL$, 2인 BVM 환기 $479{\pm}91mL$를 보였고, 1인 BVM 환기와 킹후두관기도기, 후두마스크 환기에서 각각 $386{\pm}59mL$, $365{\pm}05mL$, $351{\pm}35mL$를 보였다. 기도압에서도 기관내삽관을 통한 BVM 환기에서 가장 높은 기도압(11.67 cm $H_2O$)을 보였다. 결과적으로 기관내삽관을 통한 BVM 환기와 2인 BVM 환기에서 1/3 백 압착법은 적절하였다.

• 한국해양공학회지
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• 제19권1호
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• pp.1-7
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• 2005

Tidal circulation in a closed bay using a variation of bottom roughness was investigated through the numerical experiments based on a finite difference multi-level model. Various distributions of bottom roughness in the bay were implemented to determine their effects. It hadbeen determined that residual currents can be generated from the differences of the bottom roughness between streaming and reverse flow directions. The magnitude of residual currents and volume flow rate increase when the relative ratio of bottom roughness between streaming and reverse flow directions increase. Circulation in the closed bay is also improved by the employment of the change of bottom roughness.

• 한국컴퓨터정보학회논문지
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• 제29권3호
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• pp.165-171
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• 2024

본 연구는 2급 응급구조사가 호흡부전 및 호흡정지 환자에게 백-밸브 마스크(BVM) 인공호흡 시 호흡량 측정기를 사용하여 적정량의 호흡량과 및 성공률을 알아보고자 한다. 연구는 2023년 12월 11일부터 12일까지 D 대학교에 재학 중인 2급 응급구조사를 대상으로 20명을 선정하여 10명은 호흡량 측정기를 이용하여 BVM 인공호흡을 교육한 실험군으로, 다른 10명은 호흡량 측정기 없이 BVM 인공호흡을 교육한 대조군으로 선정하여 2분간 인공호흡을 제공하는 실험을 하였다. 연구 결과, 대조군에서는 정확한 호흡량을 제공하지 못하였고(p=.025), 호흡 성공률 역시 실험군에서는 2분간 호흡 성공률이 높았으나 대조군에서는 유의한 차이를 보였으며(p=.001), 주관적 호흡량과 측정된 객관적 호흡량이 대조군에서 유의한 차이를 보였다(p=.010). 따라서 호흡량 측정기를 사용한 교육은 2급 응급구조사가 느끼는 주관적 호흡량을 객관적 호흡량과 일치시키고 호흡 성공률을 높여 호흡부전 및 호흡정지와 심폐소생술 시 심장정지 환자의 생존율을 높이는 데 도움이 될 것이다.

• 대한간호학회지
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• 제44권2호
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• pp.149-158
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• 2014

Purpose: This study was conducted to compare effects of open and closed suctioning methods on lung dynamics (dynamic compliance, tidal volume, and airway resistance) and hypoxemia (oxygen saturation and heart rate) in mechanically ventilated patients. Methods: This study was a cross-over repeated design. Participants were 21 adult patients being treated with endotracheal intubation using a pressure-controlled ventilator below Fraction of Inspired Oxygen ($FiO_2$) 60% and PEEP $8cmH_2O$. Data were collected at baseline and 1, 2, 3, 4, 5, and 10 minutes after suctioning. Data were analyzed using two-factor ANOVA with repeated measures on time and suctioning type. Results: Effects of the interaction between suction type and time were significant for oxygen saturation and heart rate but not significant for dynamic compliance, tidal volume, or airway resistance. Prior to performance of suctioning, tidal volume and oxygen saturation were significantly lower, but airway pressure and heart rate were significantly higher using the closed suctioning method as compared with the open suctioning method. Conclusion: For patients on ventilator therapy below $FiO_2$ 60% and PEEP $8cmH_2O$, open suctioning performed after delivery of 100% $FiO_2$ using a mechanical ventilator may not have as much negative impact on lung dynamics and hypoxemia as closed suctioning.

• Journal of Acupuncture Research
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• 제32권4호
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• pp.195-201
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• 2015

Objectives : The purpose of this study is to report on the improvement of respiratory function of a fascioscapulohumeral muscular dystrophy patient after receiving Korean medical treatment. Methods : This study was carried out on a 60 year-old male patient who suffered from fascioscapulohumeral muscular dystrophy. While we carried out Korean medical treatment, we observed $EtCO_2$ (end-tidal carbon dioxide), Vte (exhaled tidal volume) and PIP (peak inspiratory pressure). Results : $EtCO_2$ count decreased from 34 mmHg to 24 mmHg during the treatment period, and PIP count became stable. Vte count also did not worsen in this study. Conclusions : Based on this study, we concluded that Korean medical treatment could be effective in treating fascioscapulohumeral muscular dystrophy patients with respiratory failure.

• Journal of Electrical Engineering and Technology
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• 제10권6호
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• pp.2271-2276
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• 2015

A superconducting synchronous generator (SCSG) can be expected to decrease the size and weight compared to conventional tidal current generators. This paper proposes an optimal design of a 2 MW class SCSG for a tidal current power generation system. The proposed optimal design of the SCSG will reduce the length of the high-temperature superconducting wire as well as the weight and volume of the SCSG. The 3D finite element method is used to analyze the magnetic field distribution. The optimized 2 MW SCSG is compared with a 2 MW conventional generator. As the optimized SCSG is more compact and lighter than a conventional generator, it will be efficiently applied to practical tidal power systems.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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• pp.74-79
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• 2006

General formula are presented for the maximum power available from the tidal head in a closed basin and from the tidal currents in a channel connecting two large bodies of water. In the latter case, the available energy cannot be estimated from the kinetic energy flux in the undisturbed state, but can be obtained from knowledge of the tidal head between the ends of the channel and the maximum volume flux in the undisturbed state. The results are supported by detailed calculations for Johnstone Strait, British Columbia, using a two-dimensional finite element model. The model also allows an extension to the case of multiple channels. More work is needed to allow for partial tidal fences which do not occupy the whole cross-section of a channel.

• Ocean and Polar Research
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• 제38권4호
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• pp.315-324
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• 2016

In this study, we investigated changes in the macrobenthic community in Sihwa tidal flat before and after the operation of a Tidal Power Plant (TPP). In order to investigate changes in the macrobenthic community structure, field surveys were conducted at eighteen stations in 4 transect lines every September from 2011 to 2015. Mean density of macrobenthos decreased to $116ind./m^2$ in 2015 from $1,602ind./m^2$ in 2011. While the mean density of macrobenthos has decreased, species richness and biomass have gradually increased. The species diversity and SEP (Shannon-wiener Evenness Proportion) have also gradually increased over time since the operation of the TPP. The macrobenthic community in Sihwa tidal flat was divided into 4 groups on a yearly base. Before the operation of TPP, opportunistic species such as Neanthes succina and Polydora cornuta largely contributed to the structure of the macrobenthic community, while equilibrium species such as Periserrula leucophryna and Scopimera globosa contributed after the operation. With the operation of TPP, the macrobenthic community has rapidly recovered and this might be related to improvement in the quality of water and sedimentary environments as a result of an increase in water mass volume exchanged through the TPP gate.