• Clinical and Experimental Pediatrics
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• 제61권11호
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• pp.339-347
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• 2018

Acute kidney injury (AKI) is characterized by abrupt deterioration of renal function, and its diagnosis relies on creatinine measurements and urine output. AKI is associated with higher morbidity and mortality, and is a risk factor for development of chronic kidney disease. There is no proven medication for AKI. Therefore, prevention and early detection are important. Physicians should be aware of the risk factors for AKI and should monitor renal function in high-risk patients. Management of AKI includes optimization of volume status and renal perfusion, avoidance of nephrotoxic agents, and sufficient nutritional support. Continuous renal replacement therapy is widely available for critically ill children, and this review provides basic information regarding this therapy. Long-term follow-up of patients with AKI for renal function, blood pressure, and proteinuria is recommended.

• Journal of Chest Surgery
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• 제12권4호
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• pp.365-370
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• 1979

The first Mitral Commissurotomy was performed for tight mitral stenosis on March 1957. The patient was at that time 22-year-old male, student. The longest follow 9p for 22 years and 8 months has been obtained. During the follow up period, late deterioration due to restenosis developed 4 years after initial good result and reoperation was succeeded by transventricular Mitral Valvotomy with Tubb`s ilator on April 1964. The possible cause of restenosis was attributed to recurrent rheumatic activity. After more than 13 years long-good life following 2nd operation, Endocarditis such as episode of high fever & chill intermittently followed by mild fever and night sweat, I t. tibial artery embolization and rupture of aortic cusp. At present, patient complained of no subjective symptom, enjoying ordinary life {NYHA II]. Blood pressure has been 110/50-60 mmHg, trivial diastolic murmur at apex and moderate degree of mechanical murmur on diastole at Erb`s rea. Neither signs of RVH for mitral stenosis nor sign of LVH. ST-T change for aortic regurgitation appeared yet during last 2 yrs. The patient`s are for prevention of Rheumatic activity and development of endocarditis is important for obtaining the better long-term result.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.5-6
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• 2017

Ultra high-strength concrete can prevent spalling by mixed ratio of PP and NY fiber. However, there is a lack of research on the deterioration of strength due to changes in mechanical properties after spalling prevention. In this study, the effect of high temperature on the mechanical properties of 150MPa concrete mixed with PP and NY fiber was evaluated. As a result, mixing PP and NY fiber is judge to be little effect on the mechanical properties of the 150MPa concrete at high temperature.

• Tuberculosis and Respiratory Diseases
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• 제86권3호
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• pp.183-195
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• 2023

Bronchiectasis, which is characterized by irreversibly damaged and dilated bronchi, causes significant symptoms, poor quality of life, and increased economic burden and mortality rates. Despite its increasing prevalence and clinical significance, bronchiectasis was previously regarded as an orphan disease, and ideal treatment of this disease has been poorly understood. The European Respiratory Society and British Thoracic Society have recently published guidelines to assist physicians in the clinical field. Guidelines and reports suggest comprehensive management that includes both non-pharmacological and pharmacological treatment. Physiotherapy and pulmonary rehabilitation are two of the most important non-pharmacologic therapies in bronchiectasis patients; long-term inhaled antibiotics and macrolide therapy have gained significant evidence in reducing exacerbation risk in frequent exacerbators. In this review, we summarize recent updates on bronchiectasis treatment to prevent exacerbation and manage clinical deterioration.

• 한국정보통신학회논문지
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• 제6권2호
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• pp.141-150
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• 2002

본 논문에서는 주파수 도약 시퀀스를 사용하는 직교 멀티캐리어 FH/CDMA 시스템을 구성해 보고 지연된 다른 사용자 신호들에 의한 충돌 발생 가능성을 사용자 접속 캐리어 슬롯 수에 따라 변화시켜 가면서 성능 저하에 큰 영향을 미치지 않는 최적의 사용자 접속 캐리어 슬롯 수를 찾아보았다. 아울러 시스템의 TCM과 Concatenated code 기법을 적용하여 BER 성능 개선 정도를 컴퓨터 시뮬레이션을 통해 평가하였다.

• Journal of Dairy Science and Biotechnology
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• 제30권2호
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• pp.75-81
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• 2012

Molds cause severe cheese deterioration, even though some white and blue molds are used for the manufacture of Camembert and Blue cheese, respectively. The species of Geotrichum, Moniliella, Aspergillus, Penicillium, Mucor, Fusarium, Phoma, and Cladosporium are the main fungi that affect contamination during cheese ripening. Once deteriorated by fungal spoilage, cheese becomes toxic and inedible. Fungal deterioration of cheese decreases the nutritional value, flavor profiles, physicochemical and organoleptic properties, and increases toxicity and infectious disease. Fungal contamination during cheese ripening is highly damaging to cheese production in Korean farmstead milk processing companies. Therefore, these companies hesitate to develop natural and ripened cheese varieties. This article discusses the recent and ongoing developments in the removal techniques of fungal contamination during cheese ripening. There are 2 categories of antifungal agents: chemical and natural. Major chemical agents are preservatives (propionic acid, sodium propionate, and calcium propionate) and ethanol. Among the natural agents, grapefruit seed extract, phytoncide, essential oils, and garlic have been investigated as natural antifungal agents. Additionally, some studies have shown that antibiotics such as natamycin and Delvocid$^{(R)}$, have antifungal activities for cheese contaminated with fungi. Microbial resources such as probiotic lactic acid bacteria, Propionibacterium, lactic acid bacteria from Kimchi, and bacteriocin are well known as antifungal agents. In addition, ozonization treatment has been reported to inhibit the growth activity of cheese-contaminating fungi.

• Smart Structures and Systems
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• 제6권3호
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• pp.277-290
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• 2010

Internationally the load carrying capacity of bridges is decreasing due to material deterioration while at the same time increasing live loads mean that they are often exposed to stresses for which they were not designed. However there are limited resources available to ensure that these bridges are fit for purpose, meaning that new approaches to bridge maintenance are required that optimize both their service lives as well as maintenance costs. Wireless sensor networks (WSNs) provide a tool that could support such an optimized maintenance program. In many situations WSNs have advantages over conventional wired monitoring systems in terms of installation time and cost. In order to evaluate the potential of these systems two WSNs were installed starting in July 2007 on the Humber Bridge and on a nearby approach bridge. As part of a corrosion prevention strategy, a relative humidity and temperature monitoring system was installed in the north anchorage chambers of the main suspension bridge where the main cables of the bridge are anchored into the foundation. This system allows the Bridgemaster to check whether the maximum relative humidity threshold, above which corrosion of the steel wires might occur, is not crossed. A second WSN which monitors aspects of deterioration on a reinforced concrete bridge located on the approach to the main suspension bridge was also installed. Though both systems have provided useful data to the owners, there are still challenges that must be overcome in terms of monitoring corrosion of steel, measuring live loading and data management before WSNs can become an effective tool for bridge managers.

• 전자공학회논문지SC
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• 제45권3호
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• pp.51-58
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• 2008

본 논문은 반도체를 이용한 열화방지형 파워폴딩 제어기 설계에 관한 연구이다. 파워기술은 자동차용 사이드 미러 접이 콘트롤러, 와이퍼 콜트롤러, 안테나 콘트롤러, 파워윈도우 콘트롤러 등에 사용되고 있는 모터제어기술로 기존의 제어 방식은 DC 모터, 스위칭 소자 그리고 Relay 등을 조합한 방식을 채택하고 있다. 그러나 이러한 방식은 동작에 대한 신뢰성 및 내구성, 노이즈 등의 문제점을 극복하는데 한계를 갖고 있다. 따라서 본 논문에서는 모터의 동작을 감시하기 위한 방법으로 부하감지부에서 Motor의 Brush Noise를 감지하도록 하였고, R, C 충 방전 시정수에 의한 정밀시간 제어 방법으로 모터의 열화현상을 최소화하였다. 그리고 스위칭 소자로 반도체 소자인 MOSFET를 사용함으로써 동작의 안정성과 수명의 한계를 극복할 수 있는 제어장치를 설계하였다. 연구결과 모터의 반복 동작시간, Cut-off Time, 동작전압 범위, 전원 발생 노이즈 등에서 최대 11배 이상 향상된 효과를 얻을 수 있었다.

• 한국산업보건학회지
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• 제30권1호
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• pp.18-27
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• 2020

Objectives: For testing asbestos stabilizer products which are used for the maintenance and management of asbestos-containing materials, durability assessment should accompany the evaluation of basic properties and performance. Therefore, in this study we designed a testing method and constructed a database of durability performance, thereby providing basic data for reliability studies of asbestos stabilizer. Methods: Since the ceiling materials targeted in this study are interior materials, test conditions of 95% relative humidity and 60℃ temperature were designed in consideration of the effect of high relative humidity in summer and seasonal indoor temperatures. Plate-shaped specimens treated with asbestos stabilizers were maintained in a thermo-hygrostat for 5, 10, and 20 days, and then the asbestos scattering prevention rate was measured by air erosion testing. Results: The scattering concentration tended to increase with time under the single humidity condition, and exceeded the indoor air quality standard of 0.01 f/cc, during the 20 days of maintenance. On the other hand, there was little change according to the temperature condition. In the case of a complex condition with temperature and humidity, the results were similar to the humidity test, but the scattering concentration increased more sharply at 20 days. Conclusions: The main deterioration factor that affects the durability of asbestos stabilizer is humidity, and the deterioration is caused by a mechanism in which the stabilizer coated on the surface is re-dissolved by moisture and evaporates or the coating layer is peeled off, which is accelerated by high temperatures.

• 환경영향평가
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• 제20권5호
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• pp.705-716
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• 2011

For the efficient discovery of knowledge and information from the observed systems, data mining techniques can be an useful tool for the prediction of water quality at intake station in rivers. Deterioration of water quality can be caused at intake station in dry season due to insufficient flow. This demands additional outflow from dam since some extent of deterioration can be attenuated by dam reservoir operation to control outflow considering predicted water quality. A seasonal occurrence of high ammonia nitrogen ($NH_3$-N) concentrations has hampered chemical treatment processes of a water plant in Geum river. Monthly flow allocation from upstream dam is important for downstream $NH_3$-N control. In this study, prediction models of water quality based on multiple regression (MR), artificial neural network and data mining methods were developed to understand water quality variation and to support dam operations through providing predicted $NH_3$-N concentrations at intake station. The models were calibrated with eight years of monthly data and verified with another two years of independent data. In those models, the $NH_3$-N concentration for next time step is dependent on dam outflow, river water quality such as alkalinity, temperature, and $NH_3$-N of previous time step. The model performances are compared and evaluated by error analysis and statistical characteristics like correlation and determination coefficients between the observed and the predicted water quality. It is expected that these data mining techniques can present more efficient data-driven tools in modelling stage and it is found that those models can be applied well to predict water quality in stream river systems.