• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2008.05a
• /
• pp.521-524
• /
• 2008

Effect of prior deformation on the sliding wear of the ultra-fine grained (UFG) ferrite-martensite dual phase (DP) steel was investigated. The UFG DP steel was fabricated by the ECAP and subsequent intercritical annealing. The steel was cold rolled before the wear test, and the effect of the prior deformation on the wear was examined. The wear tests were carried out at various loads against a bearing steel ball. The wear rate of the UFG DP steel that did not experience the prior deformation was higher than that of the coarse-grained (CG) DP steel, because of more severe surface shear deformation. The wear rate of the specimens with prior deformation was much higher than that of the specimen without prior deformation. The deformed CG DP specimen showed higher rate than the deformed UFG DP specimen, and the rate-variation of the CG DP steel was much bigger under the same test condition.

• The Journal of Internal Korean Medicine
• /
• v.27 no.3
• /
• pp.770-775
• /
• 2006

Objectives : This study was designed to evaluate the effects of oriental treatment on cancer patients. Methods : We retrospectively analyzed the medical record of a distal cholangiocarcinoma patient who had been treated with oriental medicine for 150 days. He complained of anorexia, dyspepsia, fatigue, weight loss, constipation, abdominal discomfort and pain. etc. We prescribed him Samchulkunbi-tang and other oriental medicines, in order to treat symptoms and improve long term survival. Results and Conclusion : For 150 days, he was treated with oriental medicine and the symptoms mostly disappeared. We had a worthwhile improvement of long term survival. When it comes to therapeutic effects, it could be suggested that oriental medicine has significant effects on improving symptoms, survival and quality of lifes.

• The Journal of Internal Korean Medicine
• /
• v.27 no.3
• /
• pp.751-761
• /
• 2006

Atrial fibrillation (AF) is a common arrhythmia that is a potent independent risk factor for stroke. The incidence of AF increases with age and most affected people have underlying cardiac disease. An aging society increases the incidence of AF patients. The case was designed to evaluate the improving effect of Chengsim Yeunja-tang (CYT) for atrial fibrillation (AF) with Cb-infarction patients. This patient was treated with CYT and had significant improvement in symptoms and change of EKG. -Heart rate decreased in patients with higher than normal heart rate -RV5+SV1 voltage decreased (LVH improved) -Arrhythmia remained steady. -Palpitation. chest discomfort, dyspnea, headache, dizziness diminished. Results suggest that CYT is an effective treatment for Taeumin AF patients.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2019.10a
• /
• pp.420-423
• /
• 2019

최근 국내에서 발생되고 있는 사이버 공격들의 대부분은 기존 보안장비로 탐지가 어려운 지능형 공격으로 2017년 한 해 동안 발생한 사이버 공격의 경제적 피해액은 약 77조원에 달하고 있다. 또한 이러한 공격을 탐지하는데 평균 145일 정도가 소요되고 있으며 국내 기업 중 약 70% 가량은 사이버 공격을 적극적으로 대응하고 있지 않다. 이러한 공격들은 대부분 과거에 발생한 공격의 변형이거나, 특정 공격 집단이 수행하는 유사/변종 공격들이다. 이러한 사이버 공격을 사전에 탐지하거나 이미 발생된 공격의 변형된 공격을 신속하게 탐지하기 위해서 본 논문에서는 기존 사이버 공격에 사용된 다양한 정보들을 능동적으로 수집하여, 이들 간의 연관성을 분석하고, 실시간으로 유입되는 공격 의심정보와 비교분석하는 기술을 제시한다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2019.10a
• /
• pp.34-37
• /
• 2019

The drone uses a Microwave Doppler Radar Sensor which operates at 10.525GHz to recognize harmful animal which intruded into the arable land. Moreover provide user with notification services on risk factors. Subsequently, the user the drone's camera and a camera-only app to watch the farmland in real-time, steer the drone directly, and use the NeoPixel LED ring and the speaker to stimulate the harmful animal's sight and hearing to induce escape.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2018.05a
• /
• pp.110-110
• /
• 2018

상수관로의 노후화는 단수유발, 수압부족 및 수질악화, 싱크홀 발생 피해와 누수로 인한 경제적 손실 등을 초래한다. 최근 상수관로의 노후화에 의한 피해가 심각해짐에 따라, 환경부에서는 전국적으로 노후관로를 개량 및 교체하는 작업을 시행하고 있다. 다만, 모든 노후관로를 일시에 보수 및 교체하는 것은 불가능하므로, 사용 중인 관로의 노후도를 정량적으로 판단하여 개량우선순위를 결정해야한다. 현재 국내에서는 '상수도 기술진단' 매뉴얼에 따른 관망성능평가 결과를 이용하여 상수관로의 노후화 정도를 평가하고 있다. 이는 평가항목 별로 기준을 나누어 조건값과 가중치를 부여하고, 총 점수를 합산하여 해당 관로의 평가 점수에 따라 등급을 판정하게 되는 점수평가법이다. 본 연구에서는 기존의 점수평가법과의 비교를 통하여, ANN(Artificial Neural Network)-Clustering 기법이 상수관로의 노후도 평가를 위한 새로운 평가방법이 될 수 있음을 제시하였다. 본 연구는 강원도 Y지역의 상수관로를 대상으로 진행하였으며, 기존의 관망성능평가 항목을 이용하여 전체 관로를 세 가지 등급으로 분류하여 노후도를 평가하였다. 또한 ANN-Clustering방법의 적용 가능성을 판단하기 위하여 기존의 점수평가법 결과와 비교분석을 실시하였으며, 전체 대상관로의 노후도 정도를 직관적으로 파악할 수 있도록 계산된 노후도 등급을 관망도에 도시하였다. ANN-Clustering방법은 관로의 다양한 특성값을 손쉽게 변경하여 적용할 수 있으며, 기존의 점수평가법과 더불어 상수관로의 유지관리를 위한 보다 객관적이고 합리적인 관망성능평가법이 될 수 있을 것으로 기대한다.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2019.05a
• /
• pp.103-103
• /
• 2019

본 연구에서는 Terra MODIS 위성영상과 Mapping Evapotranspiration at high Resolution with Internalized Calibration (METRIC) 모형을 이용하여 2012년부터 2017년까지 한반도 전국의 증발산량을 산정하고 플럭스 타워 실측 증발산량과 비교하였다. METRIC은 전 세계에 널리 적용된 바 있는 에너지 수지 기반의 Surface Energy Balance Algorithm for Land (SEBAL) 모형의 개념과 기술을 기반으로 현열(Sensible Heat Flux) 추정 모듈을 개선한 모형이다. 본 연구에서 METRIC 모형은 기존 C#으로 개발되어 있던 SEBAL 코드에서 현열 추정 모듈을 수정하였고 연산 속도 개선을 위해 Python으로 재작성하였다. METRIC 모형의 위성 자료로 Terra MODIS 위성의 MOD13A2(16day, 1km) NDVI, MOD11A1(Daily, 1km) Land Surface Temperature (LST) 및 MCD43A3(Daily, 500m) Albedo를 구축하였으며 500m 공간해상도의 Albedo는 1000m 해상도로 resample하여 활용하였다. 기상자료는 기상청 기상관측소의 풍속, 풍속측정높이, 습도, 10분 간격 이슬점 온도, 일사량 자료를 위성 자료와 같은 공간해상도로 내삽(Interpolation)하여 구축하였다. 모형결과 검증을 위해 국내 플럭스 타워 (설마천, 청미천, 덕유산) 증발산량 관측 자료와의 결정계수(Coefficient of determination, $R^2$), RMSE(Root mean square error) relative RMSE (RMSE%), Nash-Sutcliffe efficiency (NSE) 및 IOA(Index of Agreement)를 산정하고, 기존 SEBAL 모형 결과와의 비교를 통해 본 모형의 개선점을 보이고자 한다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.11 no.5
• /
• pp.588-597
• /
• 1999

Sokkuram grotto, a UNESCO cultural heritage in Kyongju Korea, was originally covered with crushed rocks over its dome with ventilating holes. The grotto was perfectly preserved for more than 12 centuries until the upper structure was replaced with a concrete dome in the early 20th century to protect from total collapse. Since then, heavy dew formed on the granite surface to seriously damage the sculptures until it was further remodeled with air-conditioning facilities in the 60s. It is considered that the original upper porous structure had a dehumidifying capability. This research is made to unveil the dehumidifying mechanism of the rock layer during the rainy season in that area. A rock layer and a concrete layer are tested in a temperature/humidity-controlled room. No dew formation is observed for the two specimen for continued sunny days or continued rainy days. However, heavy dew formed on the concrete surface for a sunny day after long rainy days. It is thought that the sun evaporates water on the ground and dew is formed at the surface as the highly humid air touches the yet cold concrete. On the contrary, no dew formation is observed for the rock layer at any time. Even in the above worst situation, air flows downward through the cool rock layer and moisture is removed before reaching inside. Temperature measurement, flow visualization, observation of dew formation and measurement of air velocity are made to verify the mechanisms.

• Journal of Korean Critical Care Nursing
• /
• v.14 no.3
• /
• pp.62-72
• /
• 2021

Purpose : This study aimed to identify factors influencing clinical nurses' intention to report medication administration errors. Methods : This cross-sectional study collected data from 121 nurses in charge of administering medication at a university hospital in Korea using structured questionnaires. Data were analyzed using descriptive statistics, independent t-test, one-way ANOVA, Pearson's correlation coefficient, and multiple linear regression. Results : Participants' mean age was 26.90±3.99 years, and 89.3% were women. Their mean clinical career duration was 3.88±4.26 years. The average levels of patient safety culture, attitude toward reporting medication administration errors, and intention to report medication administration errors were 7.51 out of 10, 3.36 out of 5, and 4.85 out of 6, respectively. The multiple regression analysis results indicated that the statistically significant influencing factors were patient safety culture (𝛽=.21, p =.018) and attitude toward reporting medication administration errors (𝛽=.22, p =.015). Conclusion : To improve the intention to report medication administration errors among clinical nurses, a patient safety culture must be established, along with an education provision for improving their attitudes toward reporting such administration errors.

• Journal of Korean Society of Water and Wastewater
• /
• v.33 no.3
• /
• pp.225-234
• /
• 2019

This study is focused on effects of factors that affect the formation of THMs during chlorination in drinking water treatment. During the chlorination, chlorine consumption is increased by increasing the initial chlorine dose, the pH and the total dissolved solid (TDS) concentration. Also THMs formation is increased up to $58.82{\mu}g/L$ and $55.54{\mu}g/L$ by increasing initial chlorine concentration and increasing pH. However, concentration of chloroform is decreased by increasing TDS concentration. This is caused the cation($Na^+$) of the total dissolved solids preferentially reacts with the functional groups of the organic material which influence the trihalomethane formation. But total trihalomethane formation is increased up to $127.46{\mu}g/L$ by $Br^-$ contained in the total dissolved solids. DOC reduction was not influenced by any of the factors.