• 제목/요약/키워드: numerical methods

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Morphine과 Morphine-Ketorolac Tromethamine의 지속적 정주에 의한 술후 통증치료 효과 비교 (Effects of Morphine and Morphine-Ketorolac Tromethamine Intravenous Infusion for Postoperative Pain)

  • 이광수;이강창;송윤강;김태요;윤재승
    • The Korean Journal of Pain
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    • 제8권1호
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    • pp.37-42
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    • 1995
  • The intermittent injection of analgesics is a inadquate method for postoperative pain control. Recently a non-electroic, disposable and portable infusor (Boxter Two Day $Infusor^R$) has been developed which can deliver analgesics with 2 ml/h speed continuousely. The present study examined the effects of three methods of pain management on recovery in 306 patients undergoing elective surgery in Wonkwang University Hospital. Group 1 (n=106) received i.m. $Valentac^R$ on a PRN basis. Group 2 (n=100), initial 2 mg of bolus morphine was followed by 48 mg of continuous infusion. Group 3 (n=100), initial 2 mg of morphine followed by morphine 18 mg-ketorolac 120 mg. We evaluated an analgesic efficacy with NRS (numerical rating scale) at 12, 24, 36, 48, 60 and 72 hours after the operation. The side effects (nausea, vomiting, pruritus, sedation and respiratory depression) were evaluated. In group 1, we asked major concern before operation and efficacy of pain control with pain severity (no pain, mild pain, moderate pain, sever pain). The results were as follows: 1) Major concern before operation is pain (40%). 2) 53% of patients suffered pain in group 1. 3) Morphine and morphine-ketorolac infusion groups were superior to the i. m. ($Valentac^R$) group with respect to postoperative analgesia. 4) In group 3 (morphine-ketorolac), there was no pruritus and mild nausea and vomiting.

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전자궁적출술후 시행한 정맥내 통증자가조절법의 임상 경험 (Clinical Experience on Intravenous Patient Controlled Analgesia after Total Abdominal Hysterectomy)

  • 김윤희;최훈
    • The Korean Journal of Pain
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    • 제12권1호
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    • pp.54-58
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    • 1999
  • Background: We studied 150 patients who received intravenous patient controlled analgesia (PCA) after total abdominal hysterectomy to evaluate pain relief, analgesic consumption, patient's satisfaction and side effects. Methods: We made total 40 ml of analgesic mixture with morphine 40 mg, ketorolac 120 mg, droperidol 3 mg and normal saline. Loading/bolus/basal infusion dose and lockout interval was 2 ml, 1.5 ml, 0.5 ml/hr and 10 min, respectively. Numerical rating scale (NRS) pain score, cumulative analgesic consumption, degree of satisfaction, and incidence of side effects were evaluated. Also, correlation of age and edu ion with analgesic consumption were evaluated. Results: The average pain scores using NRS were $3.1{\pm}1.7$ (6 h), $2.1{\pm}1.5$ (24 h), $1.7{\pm}1.5$ (48 h). The average cumulative analgesic consumption were $11.7{\pm}5.0$ ml (6 h), $23.0{\pm}6.7$ ml (24 h), $32.1{\pm}3.7$ ml (48 h). The degree of satisfaction in postoperative pain control was good in 94% of patients. There was no correlation between degree of satisfaction and analgesic consumption. Also age and level of edu ion did not correlated with analgesic consumption. Conclusions: Intravenous PCA with morphine, ketorolac, and droperidol is an effective method of postoperative pain control because it provides adequate pain relief and a few side effects with high patient's satisfaction. However, age and level of education did not correlated with analgesic consumption.

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원통형 콘크리트 사일로의 발파해체 전도공법 적용을 위한 사전취약화 구조해석 (Structural Analysis of the Pre-weakening of a Cylindrical Concrete Silo for the Application of Overturning Explosive Demolition Method)

  • 최훈;김효진;박훈;윤순종
    • 화약ㆍ발파
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    • 제27권2호
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    • pp.12-18
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    • 2009
  • 최근 노후화와 기능적 요건을 만족시키지 못하여 사용이 불가능한 원통형 사일로 구조물의 해체 수요가 증가하고 있다. 이 연구는 원통형 콘크리트 사일로 구조물의 전도공법에 의한 발파해체를 위한 사전취약화와 관련된 연구이다. 기존의 발파해체를 위한 사전취약화 작업의 경우 시공기준의 부재로 인해 경험에 의해 시공되어 왔으며, 이러한 경험적 시공은 시공도중 구조물이 붕괴 또는 뜻하지 않는 기타 사고로 이어질 수 있는 위험성을 내포하고 있다. 따라서 이 연구에서는 이러한 현실적 상황을 고려 원통형 콘크리트 사일로 구조물의 사전취약화 설계의 과정을 소개하여 원통형 콘크리트 사일로 구조물 및 이와 유사한 형태의 구조물의 사전취약화와 관련된 설계지침을 마련하기 위한 기초자료를 제공하고자 하였다. 이를 위해 국내에 있는 원통형 콘크리트 사일로 구조물을 대상으로 시공계획 순서대로 사전취약화를 실시하였으며, 사전취약화에 따른 유한요소해석 및 구조 해석을 각각 실시하여 사전취약화에 따른 구조물의 안전성 및 공법의 적용가능성을 검토하였다.

상백피 분말 첨가 식빵의 품질특성 및 제조조건 최적화 (Quality Characteristics and Optimization of Bread with Mori Cortex Radicis Powder Using Response Surface Methodology)

  • 정민주;정희선;주나미
    • 한국식생활문화학회지
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    • 제28권5호
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    • pp.512-524
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    • 2013
  • The purpose of this study was to investigate the antioxidative effects of Mori Cortex Radicis powder and to determine the optimal mixing ratio of Mori Cortex Radicis powder and water in the preparation of bread. The optimal sensory composite recipe was determined by producing bread with different levels of Mori Cortex Radicis powder and water. The analysis was performed using response surface methodology and a sensory evaluation was performed with the data. Ten experimental recipes, including two with reference points in the composition, were selected. In terms of the antioxidative effects of Mori Cortex Radicis powder, the $IC_{50}$ for total phenolic content and DPPH free radical scavenging activity were 149.56 GAE/g dry powder and 137.77 /mL respectively. Measurement results of the mechanical properties showed differences in volume (p<0.05), baking loss (p<0.05), yellowness (p<0.01), lightness (p<0.01), redness (p<0.01), hardness (p<0.01) and springiness (p<0.05). The sensory measurements showed significant values for color (p<0.05), appearance (p<0.05), flavor (p<0.01), taste (p<0.01), and overall quality (p<0.01). Overall, based on numerical and graphical methods, the optimal formulation was determined to be 21.16 g of Mori Cortex Radicis powder and 372.47 g of water.

히트싱크 베이스의 두께 변화가 방열성능에 미치는 영향 (Effect of the variation of base thickness on the heat release performance of the heat sink)

  • 김정현;이교우
    • 한국산학기술학회논문지
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    • 제15권8호
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    • pp.4749-4755
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    • 2014
  • 본 연구는 고용량 인버터 등의 열 발생 환경에서 히트싱크의 방열성능을 극대화하기 위한 파라미터 연구의 일환으로 히트싱크 베이스 두께 변화에 대한 방열성능 변화를 조사하였다. 베이스 두께가 각각 5, 9.5 및 14 mm인 히트싱크의 방열성능을 히트싱크 베이스의 윗면 중앙 온도, 히트싱크를 통한 방열량 및 열원부의 온도 등의 세 가지 지표의 비교를 통하여 고찰하였다. 실험연구와 전산유체역학 프로그램을 이용한 해석연구를 병행하여 베이스 두께 변화에 따른 각 방열 성능 지표에 변화가 있음을 확인하였다. 베이스의 윗면 중앙 온도와 방열율은 베이스의 두께가 얇을수록 향상되는 효과를 보였고, 베이스 열원부의 온도는 베이스의 두께가 두꺼울수록 낮아지는 경향을 보였다. 성능 지표의 비교 고찰을 통해 연구에 사용된 세 히트싱크 내에서는 베이스의 두께가 9.5 mm인 히트싱크에서 최적점이 나타났다. 따라서 제한적이지만 본 연구결과 내에서는 9.5 mm 두께의 베이스를 가지는 히트싱크가 최적의 방열 성능을 보이는 것으로 판단되었다.

전자빔 용해 방법으로 제조된 정형외과 임플란트용 Ti-6Al-4V 합금의 재료 특성 분석 (Material Characteristics of Ti-6Al-4V Alloy Manufactured by Electron Beam Melting for Orthopedic Implants)

  • 강관수;정용훈;장태곤;양재웅;정재영;박광민;우수헌;박태현
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2018년도 춘계학술대회 논문집
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    • pp.25-25
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    • 2018
  • Electron beam melting (EBM) is one of powder based additive manufacturing technology used to produce parts for high geometrical complexity and directly with three-dimensional computer aided design (CAD) model. It is kind of the most promising methods with additive manufacturing for a wide range of medical applications, such as orthopedic, dental implant, and etc. This research has been investigated the microstructure and mechanical properties of as fabricated and hot iso-static pressing (HIP) processed specimens, which are made by an Arcam A1 EBM system. The Ti-6Al-4V titanium alloy powder was used as a material for the 3 dimensional printing specimens. Mechanical properties were conducted with EBM manufacturing and computer numerical control (CNC) machining specimens, respectively. Surface morphological analysis was conducted by scanning electron microscopy (SEM) for their surface, dissected plan, and fractured surface after tensile test. The mechanical properties were included tensile stress-strain and nano-indentation test as a analysis level between nano and macro. As following highlighted results, the stress-strain curves on elastic region were almost similar between as fabricated and HIP processed while the ductile (plastic deformed region) properties were higher with HIP than that of as fabricated processed.

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상대 운동과 최적화 기법을 이용한 정지궤도 위치유지에 관한 연구 (New Method for Station Keeping of Geostationary Spacecraft Using Relative Orbital Motion and Optimization Technique)

  • 정옥철;노태수;이상철;양군호;최성봉
    • 한국항공우주학회지
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    • 제33권1호
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    • pp.39-47
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    • 2005
  • 본 논문에서는 정지궤도 위성의 상대 운동과 최적화 기법과의 결합을 통해 새로운 형태의 위치유지 기법을 제안하였다. 상대 궤도 운동을 나타내기 위해 궤도 압축방법을 이용하여 비선형 미분 방정식 형태가 아닌 닫힌 해 형태의 모델을 사용하였으며, 매우 정확한 궤도 전파가 가능함을 확인하였다. 기존의 위치유지 기법은 궤도 요소를 이용하여 목표 궤도를 획득함으로써 궤도 형상을 유지하지만, 본 논문에서는 정밀한 위치유지를 위해 위성의 상대 위치를 직접 제어하였다. 최적화 목적 함수의 설정을 통해 다양한 형태의 기동 전략을 수립하였고, 구속 함수를 이용하여 상황에 따른 위치유지 범위를 설정하였다. 이 방법은 최적화 함수의 변경을 통해 다양한 위치유지 기법을 쉽게 적용할 수 있고, 그에 따른 궤도 운동을 분석할 수 있다. 비선형 시뮬레이션을 통해 위성의 위치가 허용범위 내에 적절하게 유지되고 있음을 확인하였다.

6-자유도 쿼드로터 무인항공기의 모델링 및 유도기법 설계 (System Modeling and Waypoint Guidance Law Designing for 6-DOF Quadrotor Unmanned Aerial Vehicle)

  • 이상현;김유단
    • 한국항공우주학회지
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    • 제42권4호
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    • pp.305-316
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    • 2014
  • 항공전자 장비들의 급속한 발전으로 인해 무인항공기의 크기가 소형화 되고 있으나, 무인항공기에 대해 주어지는 임무는 더욱 정확하고 복잡해지고 있다. 정지비행이 가능하고, 간단한 기계적 메커니즘을 가진 쿼드로터는 이 같은 환경에서 활동도가 점차 증가하고 있다. 그러나 쿼드로터는 구조 특성에 따라 출력의 개수보다 입력의 개수가 작은 under actuated 시스템이므로, 쿼드로터 제어에 큰 제약이 따른다. 본 논문에서는 이와 같은 쿼드로터의 단점을 해결하기 위해서 4개의 원동기 외에 2개의 추가적인 원동기를 더 부착한 모델을 제안하여, 입력의 개수와 출력의 개수가 같은 fully actuated 시스템을 구현하도록 한다. 제안한 쿼드로터 모델의 제어기를 설계하기 위해 궤환선형화 기법을 적용하였다. 수치 시뮬레이션을 수행하여 제안한 모델과 설계된 제어기의 성능을 검증하였다.

식생캐노피모델을 통한 저관리 조방형 옥상녹화시스템의 열해석 전산모의에 관한 연구 (A study on thermal simulation for extensive green roof system using a plant canopy model)

  • 김태한
    • 한국환경복원기술학회지
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    • 제15권2호
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    • pp.137-147
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    • 2012
  • GRS is an effective urban ecology restoration technique that can manage a variety of environmental functions such as ecological restoration, rainwater spill control and island heat effect from a low-impact development standpoint that can be utilized in new construction and retrofits. Recently, quantitative evaluation studies, both domestic and abroad, in the areas related to these functions, including near-earth surface climate phenomenon, heavy rainwater regulation, thermal environment of buildings, have been actively underway, and there is a trend to standardize in the form of technological standards. In particular, centered on the advanced European countries, studies of standardizing the specific insulation capability of buildings with green system that comprehensively includes the green roof, from the perspective of replacing the exterior materials of existing buildings, are in progress. The limitation of related studies in the difficulties associated with deriving results that reflect material characteristics of continuously evolving systems due in part to not having sufficiently considered the main components of green system, mechanisms of vegetation, soils. This study attempts to derive, through EnergyPlus, the effects that the vegetation-related indicators such as vegetation height, FCV, etc. have on building energy load, by interpreting vegetation and soil mechanisms through plant canopy model and using an ecological standard indicator LAI that represent the condition of plant growth. Through this, the interpretations that assume green roof system as simple heat insulation will be complemented and a more practical building energy performance evaluation method that reflects numerical methods for heat fluxes phenomena that occur between ecology restoration systems comprised of plants and soil and the ambient space.

Sub Oriented Histograms of Local Binary Patterns for Smoke Detection and Texture Classification

  • Yuan, Feiniu;Shi, Jinting;Xia, Xue;Yang, Yong;Fang, Yuming;Wang, Rui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권4호
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    • pp.1807-1823
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    • 2016
  • Local Binary Pattern (LBP) and its variants have powerful discriminative capabilities but most of them just consider each LBP code independently. In this paper, we propose sub oriented histograms of LBP for smoke detection and image classification. We first extract LBP codes from an image, compute the gradient of LBP codes, and then calculate sub oriented histograms to capture spatial relations of LBP codes. Since an LBP code is just a label without any numerical meaning, we use Hamming distance to estimate the gradient of LBP codes instead of Euclidean distance. We propose to use two coordinates systems to compute two orientations, which are quantized into discrete bins. For each pair of the two discrete orientations, we generate a sub LBP code map from the original LBP code map, and compute sub oriented histograms for all sub LBP code maps. Finally, all the sub oriented histograms are concatenated together to form a robust feature vector, which is input into SVM for training and classifying. Experiments show that our approach not only has better performance than existing methods in smoke detection, but also has good performance in texture classification.