实验室用多功能操作箱优化分析

目的：研制一种生物评测的多功能试验操作箱。方法：利用CAD技术,建立支撑台桌的三维模型及操作箱内的流体CFD模型,借助ANSYS静力学分析模块对台桌进行强度分析并优化结构;采用ANSYSFLUENT对操作箱进行换气流动模拟仿真。结果：通过对台桌结构的优化．为设计工作中解决主体框架的均布承栽提供了理论依据：通过仿真得到了内部的气流压力、速度分布图,可用来分析操作箱内气流分布的变化情况。为操作箱上的气体流路设计提供依据。结论：CAD／CAE技术是进行产品结构优化设计的有效方法,有助于对所设计的项目进行分析和评价：通过CFD技术,可利用计算机模拟并显示流场中的现象,有助于在较短时间内了解流体力学问题。     

基于有限元方法的MRI永磁体优化设计

利用仿真分析技术对磁体优化设计方法进行了研究和改进．通过CAD软件建立磁体三维仿真模型．利用有限元方法对模型进行磁场性能分析．根据磁场分布数据修改磁体结构和去除冗余材料。实验结果表明．该方法能够显著减轻磁体重量。     

基于D-H参数方法的微创手术机器人运动仿真研究

目的:为了更好地研究外科微创手术机器人的工作性能,提出一种基于D-H参数方法的机器人运动仿真研究方法。方法:通过分析机器人各关节的几何关系,建立其D-H参数模型,分别对机器人系统进行正运动学和逆运动学分析,利用Matlab软件中的Sim Mechanics模块对机器人机电系统进行建模和仿真实验。结果:仿真实验结果表明,末端执行机构的期望轨迹与实际轨迹基本一致,运动误差都在实际允许范围内,验证了机器人运动学仿真研究方法的正确性。结论:采用D-H参数方法对微创手术机器人进行运动学仿真分析具有很好的实用性和准确性,对外科手术机器人的精密设计和系统改进具有普遍的适用意义。     

CAD/CAE技术在化学发光成像仪设计中的应用研究

目的：研制一种用于生物芯片、免疫渗滤（IFA）及免疫层析（IcA）等化学发光信号检测的多用途成像仪器。方法：借助计算机辅助设计与辅助工程（cAD／cAE）技术,针对设计的多用途成像仪关键部件进行建模和仿真,对整体调焦定位架构进行分析,得到其承载静强度分布情况;以电荷耦合器件（CCD）摄像头作为热源,对其散热结构进行热～固耦合分析,得到热应力情况,在保证性能的前提下进一步优化结构。结果：通过对整体调焦定位架构和热一固耦合的仿真分析,为改进设计提供理论依据。同时,可减少开发费用及缩短开发周期。结论：CAD／cAE技术是进行产品结构优化设计的有效方法,是设计工作由经验类比方法向科学分析方法转变的重要保证,对于设计工作中提升产品性能、提高设计效率可起到积极的推动作用。     

野外折叠冰箱温度场仿真设计

目的:研究折叠冰箱内部整体气流分布和温度场分布,优化折叠冰箱结构,使其具有最大的有效存储空间和获得最佳的保温外罩厚度。方法:采用CATIA软件对折叠冰箱进行建模,采用FLOEFD对折叠冰箱整体的风场分布和温度场分布进行有限元仿真分析,获得完整的温度及风场分布模型;并实验验证仿真结果的准确性,进行优化设计仿真。结果:通过仿真优化设计获得折叠冰箱保温外罩的最佳厚度为25 mm,折叠冰箱有效容积为距离保温外罩83 mm以内的空间。结论:建立了折叠冰箱的风场分布模型和温度场分布模型,为折叠冰箱结构参数的设计提供了优化设计的方法,验证了仿真模型的正确性;实现了折叠冰箱结构紧凑、坚固耐用、储运方便的设计目标,满足了野外储运和使用的要求。     

基于Comsol Multiphysics平台仿真计算分析细胞形变伴随的局部组织电阻抗变化

目的：利用数值计算方法模拟计算细胞形状变化导致的局部组织电阻抗变化。方法：利用Comsol Multiphysics多物理场计算平台软件,建立细胞形状和电磁场数值场域参数模型。结果：建立了细胞模型,并通过软件仿真分析发现,当细胞形状变化时,周围局部组织电阻抗有变化。结论：利用现有软件平台,可直观地对细胞及组织生理参数进行建模、仿真。     

Micro CT系统中对投影图像旋转中心的校正下颌骨CADCAE建模研究

目的：为口腔生物力学的研究和优化修复体及假体的设计提供研究手段,为下颌骨各种手术方案进行虚拟手术效果分析提供模型。方法：选择一名颞颌系统发育正常的中年男性,采用螺旋CT扫描机对其下颌骨螺旋扫描,获得123幅二维扫描断层图像;采用自研图像处理软件将二维断层图像处理为三维点云,在CATIA中进行曲面拟合,建立了形状精确的下颌骨CAD模型：采用MSC．Patran建立了下颌骨手术方案所需的有限元模型。结果：建立了全牙列下颌骨的CAD模型及三维有限元模型。结论：正常下颌骨三维有限元模型真实反应了下颌骨的几何形态,与实体下颌骨具有较好的相似性,可作为生物力学研究的工具;为针对下颌骨的各种手术提供了一种术前设计的定量方法。     

三维CAD及CAE技术在高速离心机设计中的应用

采用三维CAD及CAE技术构建转子和轴的三维模型,通过有限元法算出转子应力分布情况,分析转子高速旋转过程中的强度裕度和破裂转速;对轴进行模态分析,确定其直径和长度。参照分析结果设计出来的零部件,在实际试机过程中取得了较好的一致性。这一技术方法在设计工作中对提升产品性能、提高设计效率等方面具有很强的实用性。     

一种生物气溶胶旋风式分离采集装置的设计与验证

目的:设计一种生物气溶胶旋风式分离采集装置,为小粒径生物气溶胶分离采集和分析提供有效手段.方法:对经典旋风式分离采集装置结构参数进行优化,借助Fluent软件对筒体直径等关键结构参数对粒径分离效果的影响进行模拟仿真,确定生物气溶胶旋风式分离采集装置的最优结构参数,之后采用高纯铝材料制作生物气溶胶旋风式分离采集装置.采用...     

基于虚拟样机技术的监护仪安装支架仿真分析与优化设计

目的:获取监护仪安装支架在激励作用下的动力学特性,并对其隔振系统进行优化设计。方法:结合Pro/E与ADAMS软件建立了监护仪安装支架的动力学模型,利用正弦扫描和半正弦脉冲生成可施加于模型的激励信号,对系统进行仿真分析。结果:取得了安装支架垂向加速度曲线与数据,并找到一组最优的匹配结构以减小作用于监护仪的振动强度。结论:监护仪安装支架能够降低监护仪的振动强度,可为其他医疗设备安装支架的设计提供参考。     

模拟野战环境动态输液训练电动荡板床的设计与应用

目的:研制一种适合动态、微光情况下的输液训练电动荡板床,以提高护理人员在颠簸摇晃的后送工具如汽车、轮船、飞机等环境中的静脉输液操作能力。方法:在人力荡板床的基础上进行改造加工的电动荡板床主要由避光帘支架、滚轮卡槽、滚轮、活动床板、固定床架、电动机、变频调速器等组成。将无缝钢管进行焊接形成避光帘支架,床板下方放置US-52型电动机(含减速机),在床体外侧左上方放置变频调速器。结果:该电动荡板床减少了保障人数和考核时间,提高了静脉穿刺成功率。结论:动态输液训练电动荡板床能模拟不同战场救护环境下的静脉输液训练,为灾害紧急救援护理的研究和进一步提高医护人员医疗救治能力奠定了基础。     

Interference-free automatic cardiac leads for health-related running

An autocardioleader of the PKC-2 design intended for the control of the health running speed according to the heart rate is depicted. The device is characterized by a high interference-killing feature dependent on the R wave selector. The selector is fitted out with a band-pass filter, automatic gain control, and a shaper for standard impulse formation. The parameters of the band-pass filter have been optimized with the aid of the theory of optimum filtration for average spectral models of the signal (R wave) and jamming.     

仿真技术在基因芯片杂交仪微流路设计中的应用

目的：为了加快基因芯片技术的推广和应用,研制一种集基因芯片清洗、温育、杂交等于一体的新型仪器,使整个过程可在计算机控制下自动完成。方法：借助计算机辅助设计（computeraideddesign,CAD）技术,针对基因杂交仪微流路模块进行建模;借助计算流体力学（computationalfluiddynamics,CFD）技术,应用CFX软件建模分析得到不同流路方式的液流情况;对固架承载结构进行静强度分析,得到其承载分布情况;对电加热模块进行热-固耦合分析,得到微流路模块热应力情况。结果：仿真技术为微流路设计提供了参考和依据,从而更高效地设计出了满足实验流程的基因芯片杂交、清洗微流路模块,避免了结构工艺因素的影响,使得到的实验数据更加科学可信。结论：运用仿真技术完成对微流路模块的设计研究,可以有效地缩短开发周期、节省试验成本,对于该类产品的试制与性能测试具有一定的参考意义。     

Technology assessment in dentistry: a comparison of the longevity and cost-effectiveness of inlays

OBJECTIVES: An example of technology assessment in dental care by evaluating the (cost-)effectiveness of types of three-surface inlays (gold, laboratory-fabricated ceramic, and chairside CAD/CAM ceramic) is provided. METHODS: MEDLINE, EMBASE, and the Cochrane Library were searched for studies published between 1966 and June 2003 that reported annual survival probabilities and annual observations. The longevity of different types of inlays was measured by the number of failure-free years. Annual survival rates from different studies were pooled by weighing the rates of each study by the inverse of the variance of the effect estimate. A cost-effectiveness analysis from the perspective of German private health insurers was performed using billing charges. RESULTS: Three, five, and two case series on laboratory-fabricated ceramic, chairside CAD/CAM ceramic, and gold inlays, respectively, were included. Over a 9-year observation period, the number of undiscounted failure-free years was 8.62 (95 percent confidence interval, 8.40-8.85), 8.65 (8.58-8.73), and 8.76 (8.72-8.80) for laboratory-fabricated ceramic, chairside CAD/CAM ceramic, and gold inlays, respectively. Laboratory-fabricated ceramic inlays were the most expensive. CONCLUSIONS: While laboratory-fabricated ceramic, chairside CAD/CAM ceramic, and gold inlays had a strikingly similar failure-free survival rate, laboratory-fabricated ceramic inlays had the highest costs and, thus, were less cost-effective than chairside CAD/CAM ceramic and gold inlays.     

Potential Use of Low-Cost Lignocellulosic Waste for the Removal of Direct Violet 51 from Aqueous Solution: Equilibrium and Breakthrough Studies

An efficient biosorbent, sugarcane bagasse was used in native, HCl-treated, and Na-alginate immobilized form for the removal of Direct Violet 51 dye from aqueous solutions. Batch study was performed to optimize important process parameters, such as pH, contact time, biosorbent dose, initial dye concentration, and temperature. Removal of Direct Violet 51 was found to be favorable at pH 2 with the biosorbent dose of 0.05 g. Biosorption process was found to be exothermic in nature. Maximum dye biosorption (39.6 mg/g) was achieved by using HCl-treated biomass. The pseudo-second-order kinetic and Langmuir adsorption isotherm models showed best fitness to the experimental data. Thermodynamic study was also performed to determine the feasibility of biosorption process. Continuous mode study was performed to optimize the important process parameters, such as bed height, flow rate, and initial dye concentration for maximum removal of Direct Violet 51 dye. The higher bed height, low flow rate, and high initial dye concentration were found to be the better conditions for maximum dye biosorption (17.28 mg/g). The linearized form of the Thomas model equation fitted well to the experimental data. The bed depth service time model was used to express the effect of bed height on breakthrough curves. Characterization of biosorbent was performed by scanning electron microscopy and Fourier transform infrared (FT-IR) analysis. The FT-IR spectral analyses showed the involvement of hydroxyl, carbonyl, and carboxyl groups in biosorption process. These results indicated that sugarcane bagasse biomass could be used as a novel biosorbent for the removal of Direct Violet 51 dye from real textile and related industries.     

Evaluating the Design of a Family Practice Healthcare Clinic Using Discrete-Event Simulation

With increased pressures from governmental and insurance agencies, today's physician devotes less time to patient care and more time to administration. To assist physician clinics in evaluating potential operating procedures that improve operating efficiencies and better satisfy patients, an object-oriented discrete-event simulation model has been constructed using the Visual Simulation Environment (VSE). The research presented herein describes a methodology for determining appropriate staffing and physical resources in a clinical environment using this simulation model. This methodology takes advantage of several simulation-based statistical techniques, including batch means; fractional factorial design; and simultaneous ranking, selection, and multiple comparisons. A clinic effectiveness measure is introduced that captures several objectives within a health care clinic, including profitability and patient satisfaction. An explanation of the experimental design is provided and results of the experimentation are presented. Based upon the experimental results, conclusions are drawn and recommendations are made for an appropriate staffing and facility size for a two physician family practice healthcare clinic.     

Economic impact of the introduction of an acellular pertussis vaccine in Canada: A 6-year analysis

Background

Between July 1997 and April 1998, Canadian public health agencies switched from the whole cell vaccine to the acellular vaccine for pertussis immunization. The acellular vaccine provided better efficacy and fewer adverse events than the whole cell vaccine did.

Objective

To determine the economic impact of replacing the whole cell vaccine with an acellular vaccine in Canada.

Methods

A decision analytic model was developed comparing costs and outcomes of pertussis vaccination for Canadian children born in the years 1991–2004. Effectiveness was measured as number of avoided pertussis cases as well as the number of avoided hospital admissions. Incremental costs per avoided pertussis case and per avoided hospital admission were calculated for Ministry of Health (MoH) and societal (SOC) perspectives. Various one-way sensitivity analyses as well as a Monte Carlo simulation were performed by varying key model parameters.

Results

The switch in immunization programs resulted in an incremental cost to the MoH of CAD $108 per pertussis case avoided (CAD $0.96 per child-year). From the SOC perspective, there was a savings of CAD $184 per pertussis case avoided (CAD $0.13 per child-year). The one-way sensitivity analyses provided incremental cost-effective ratios (ICERs) ranging from an incremental cost of CAD $1034 per avoided pertussis case from the MoH perspective to a saving of CAD $1583 per avoided case from the SOC perspective. The Monte Carlo simulation confirmed the robustness of these results.

Conclusions

Pertussis vaccination with AcE was cost-saving from the societal perspective and cost-effective from the Ministry of Health perspective.