• 한국재난관리표준학회지
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• 제2권4호
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• pp.67-73
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• 2009

사회기반시설은 국가 경제 활동의 기반을 형성하는 기초적인 시설이기 때문에 교량붕괴와 같은 예상치 못한 구조물 이상은 개인 및 국가적인 경제적 손실을 발생시킬 뿐만 아니라 사회문제로까지 확대될 수 있다. 따라서 사회기반시설을 이루는 구조물에 대한 지속적인 유지관리와 안전관리는 비중 있게 다루어져야 한다. 교량 유지관리를 위한 모니터링은 90년대 초에 처음 도입되어 현재는 실시간 계측과 분석이 가능한 상태로까지 발전하였으며 최근에는 첨단센서를 이용한 시스템이 개발되고 있다. 본 논문에서는 상기와 같은 모니터링 시스템을 구축함에 있어서 최근 주목받고 있는 광섬유 센서를 이용하는 경우의 경제성을 알아보기 위해 다양한 조건에 대한 비용 분석을 실시하였다. 또한 분석결과를 현재 널리 사용되고 있는 전기저항식 센서를 이용하여 모니터링 시스템을 구축하는 경우와 비교하여 광섬유 센서를 이용한 교량 모니터링 시스템의 경제성을 살펴보았다. 검토결과 광섬유 센서를 사용하여 모니터링 시스템을 구축하는 경우 많은 부분 기존의 경우보다 보다 나은 이점을 취할 수 있고 비용 측면에서도 경쟁력을 가질 수 있음을 알 수 있었다.

• 비파괴검사학회지
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• 제36권6호
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• pp.460-465
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• 2016

배관 구조물은 긴 길이를 가지며, 일정한 거리에 위치한 고정부에 설치되거나, 지중에 매설된다. 따라서 자중 또는 지반의 움직임으로 변형과 처짐이 발생하기 쉽다. 이러한 배관의 건전성 평가에는 형상 감시 기법이 매우 유용할 수 있다. 광섬유 브래그 격자 센서 (fiber Bragg grating, FBG)는 다중화의 장점이 있어 배관과 같이 긴 길이를 가지는 구조물의 여러 지점에서 변형률 측정에 매우 유용하다. 본 연구에서는 배관의 건전성 평가를 위하여 변형률 기반의 형상추정기법을 제안하였다. 제안된 기법의 유용성을 확인하기 위하여 실험을 통한 검증을 수행하였다. 실험 결과 제안된 FBG를 이용한 형상추정기법이 시험편의 변형에 따라 유사한 형상을 표현할 수 있음을 확인하였다. 또한, 형상추정기법을 통해 도출된 처짐량이 실제 배관에 가해진 처짐과 동일하게 계산됨을 확인하였다.

• 한국임상약학회지
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• 제8권1호
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• pp.35-46
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• 1998

A retrospective study was conducted to evaluate the appropriateness of total parenteral nutrition (TPN) for 200 hospitalized adult patients in Samsung Medical Center from January 1st in 1995 to June 31st in 1997. Standard criteria were modified and determined from those stated by AJHP (American Journal of Health System Pharmacy) and ASPEN (American Society of Parenteral and Enteral Nutrition). The justification for indications was appropriate in $35\%,\;44\%,\;and\;32\%$ of the patient's in 1995, 1996, and 1997, respectively, without significant improvement over the last two and half years. Before and during the administration of TPN, several monitoring indicators were well documented, and monitoring frequencies were increased over two and half years period. However, the majority of the monitoring indicators were not found in the standard criteria range of $90\%$. The monitoring indicators for electrolyte balance, $PO_4$ and Mg, were not measured appropriately and resulted in the complications which could have been prevented. The indicator for lipid tolerance, triglyceride and the indicator for hemorrhagic incidence, prothrombin time (PT), were not well documented in comparison with other indicators. The indicators for the improvement in nutritional status, albumin and total protein, were appropriate in $90\%$ of the patients. Determination of TPN formula was based on the laboratory data and chart reviews, and it was appropriate in $98\%$. But the administration of lipid and vitamin K for the prevention of essential fatty acid deficiency and hemorrhage, respectively, was not carried out appropriately when the administration of TPN was prolonged, lasting more than 7 days. When a patient returned to oral or enteral feeding, TPN was terminated. However, increase in albumin level or weight was rarely observed. In conclusion, healthcare professionals should all work as a team and active participation to provide optimized nutrition support for partners.

• International Journal of Heart Failure
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• 제6권1호
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• pp.22-27
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• 2024

Body fluid monitoring and management are essential to control dyspnea and prevent re-hospitalization in patients with chronic heart failure (HF). There are several methods to estimate and monitor patient's volume status, such as symptoms, signs, body weight, and implantable devices. However, these methods might be difficult to use for reasons that are slow to reflect body water change, inaccurate in specific patients' condition, or invasive. Bioelectrical impedance analysis (BIA) is a novel method for body water monitoring in patients with HF, and the value in prognosis has been proven in previous studies. We aim to determine the efficacy and safety of home BIA body water monitoring-guided HF treatment in patients with chronic HF. This multi-center, open-label, randomized control trial will enroll patients with HF who are taking loop diuretics. The home BIA group patients will be monitored for body water using a home BIA device and receive messages regarding their edema status and direction of additional diuretics usage or behavioral changes through the linked application system once weekly. The control group patients will receive the usual HF management. The primary endpoint is the change in N-terminal prohormone of brain natriuretic peptide levels from baseline after 12 weeks. This trial will provide crucial evidence for patient management with a novel home BIA body water monitoring system in patients with HF.

• 한국해양공학회지
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• 제27권3호
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• pp.8-14
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• 2013

Although there are various factors that threaten the security of ships, one of the most harmful is corrosion. It is not easy to find corroding areas and the status of corrosion, even though corrosion causes serious problems such as submergence and marine pollution as a result of leaking oil and polluted water. To monitor the corrosion of ships, non-destructive inspection, weight loss coupons, electrical resistance, linear polarization resistance, zero resistance ammeter, and electrochemical impedance spectroscopy have been developed. However, these methods require much time to detect corrosion, and most are not appropriate for real time monitoring. Coating, sacrificial anode, and impressed current cathodic protection (ICCP) methods have been developed to control corrosion. The ICCP and sacrificial anode methods are the most popular ways to prevent ship corrosion. However, ICCP is only appropriate for the outside of a ship and cannot be used for complex structures such as ballast tanks because these are composed of many separate chambers. Sacrificial anodes have to be replaced periodically. This paper proposes an integrated corrosion monitoring and control system (ICMCS) that can detect corrosion in real time and is appropriate for complex structures such as ballast tanks. Because the system uses titanium for an anode, exhausted anodes do not need to be replaced.

• 콘크리트학회논문집
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• 제18권2호
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• pp.293-298
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• 2006

The reinforced concrete(RC) structures strengthened with fiber reinforced plastic(FRP) has been accepted by the construction engineering community for rehabilitation. FRP composites can present many advantages like a corrosion resistance, strength-weight ratio, relatively short application time, and cost effectiveness. The beams under design load, however, are cracked and result in degrading the strength. It is difficult to recognize cracks and deflections on the surface of the concrete members retrofitted with FRP through the life cycle. For these reasons, if they result in the effects, which were below the expected strength, we must monitor the state of concrete structures all the time in order to take an appropriate measure. Fiber Bragg Grating(FBG) sensor excel as monitoring of investigating the stress state of the retrofitted beams with FRP. The main objective of this study is to measure strain by experiment and analyze the behavior of RC beams retrofitted with FRP using FBG sensor. The kinds of FRP which were used in research are carbon, glass and improved hybrid FRP(IFRP) that has capacity than any other FRP. Other variables are the length of FRP, the number of sheet.

• Ocean and Polar Research
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• 제23권3호
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• pp.305-310
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• 2001

This paper describes a floating fish reef technology for enhancement of fisheries productivity in the muddy areas. The floating fish reef was composed of main fish cage, anchor rope and concrete anchor blocks. Main fish cage was made up of 12 steel buoys measuring 0.37m in diameter and 1.5m long, polyethylene (PE) netting and circular steel rings. Each steel buoy had buoyancy of 110kgf. The size of main fish cage was 1.96 m in diameter and 3.75m in length. Monitoring on its durability was made for eight months after installation. The steel buoys fixed on main fish cage and nettings were observed to be kept safely. The wet weight of fouling organisms per unit area$(m^2)$ was 26.6kgf after eight months. Reduction in the cross-section of steel buoys and circular steel rings of main fish cage were not found. In addition, any cracks on the concrete anchor blocks were not observed.

• 한국환경성돌연변이발암원학회지
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• 제19권1호
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• pp.39-45
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• 1999

Human Carcinogenic Potency (HCP) can be estimated based on human daily exposure dose to carcinogen (Dh), body weight (Wh), 10% tumorigenic dose (TD10), and slope factor at TD10 (Q10) from 2-yr bioassay data. This approach is more relevant to humans generally exposed to low doses of carcinogens and can reduce more of extrapolation errors from high dose in animal experiments to low dose in humans than HERP (human exposure dose/rodent potency dose) proposed by Ames et al. (Science, 236, 271-280, 1987). TD50 and HERP have been routinely used to compare rodent carcinogenic potency and human carcinogenic potency, but those approaches have had limitations in extrapolation of high dose to low dose in humans. The advantages of HCP are to estimate human exposure dose (Dh) by human monitoring instead of environmental monitoring, to consider slope factor (Q10) which reflects the tendency of curve at low dose, and to use TD10 which represents much lower dose thant TD50 or HERP. HCP will be a useful parameter for the estimation of human carcinogenic potency in risk assessment and management of carcinogens.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 춘계학술대회
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• pp.722-724
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• 2016

오늘날 비만인구가 증가함에 따라서 비만을 관리하고 모니터링하는 시스템 개발의 필요성이 증대되고 있다. 그러나 대부분의 모니터링 시스템은 사용자의 신장이나 체중의 정보만을 가지고 계산하여 보여주는 역할만 하기 때문에 사용자가 운동에 대한 계획을 설계할 시에 효율성이 낮은 문제점이 있었다. 본 논문에서는 사용자의 BMI의 수치를 그래프로 나타내고, BMR수치의 등급을 나누어 사용자가 자신에 대해 이해하기 쉽게 하였다. 또한 사용자가 사용한 운동기구의 사용한 회수와 일간 소모한 Kcal를 보여줌으로써 운동 계획을 설계하는데 효율적인 웹 기반 모니터링 시스템을 연구한다.

• 한국터널지하공간학회 논문집
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• 제19권6호
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• pp.905-913
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• 2017

세그먼트 라이닝 설계시 고려하는 하중은 자중, 연직하중, 수평하중, 지반반력, 수압, 뒤채움 주입압, 부력 등이 있으며, 이 가운데 토압과 수압은 세그먼트 라이닝 설계시 콘크리트 강도, 세그먼트 라이닝의 두께 및 철근량 등을 결정하는데 가장 큰 영향을 미치는 주요 인자이다. 따라서 본 연구에서는 쉴드터널 시공단계별 계측결과를 토대로 세그먼트 라이닝에 발생하는 휨모멘트 계산하였으며, 이를 역해석 결과와 비교분석을 통하여 세그먼트 라이닝에 작용하는 토압 등을 분석하였다.