Critical care medicine: opportunities and strategies for improvement

BACKGROUND: Like other areas of health care, critical care faces increasing pressure to improve the quality while reducing the cost of care. Strategies drawn from the literature and the authors' experiences are presented. STRATEGIES AND OPPORTUNITIES FOR IMPROVEMENTS: Ten process- or structure-related areas are targeted as strategically important focuses of improvement: (1) restructuring administrative lines to better suit key processes; (2) physician leadership in critical care units; (3) management training for critical care managers; (4) triage; (5) multidisciplinary critical care; (6) standardization of care; (7) developing alternatives to critical care units; (8) timeliness of care delivery; (9) appropriate use of critical care resources; and (10) tracking quality improvement. TIMELINESS OF CARE DELIVERY: Whatever the root cause(s) of unnecessary delays, the result is inefficient use of critical care resources-and ultimately either a need for more resources or longer wait times. Innovations designed to reduce wait times and waste, such as the establishment of a microchemistry stat laboratory, may prove valuable. APPROPRIATE USE OF CRITICAL CARE RESOURCES: Possible strategies for the appropriate use of critical care resources include better selection of well-informed patients who undergo procedures. Reduction in variation among physicians and organizations in providing therapies will also likely lead to a reduction in some high-risk procedures offering little or no benefit, and therefore a reduction in need for critical care services. Better preparation of patients and families should also make end-of-life decisions easier when questions of "futility" arise. Better information on outcomes and cost-effectiveness and consensus on withdrawal of critical care treatments represent two additional strategies.     

公交车辆用可燃气体检测仪

以可编程门阵列器件FPGA和气体传感器MQ-3为核心,设计了能检测可燃物挥发气的车载式检测仪.为了保证灵敏度,采用了差动集气管结构;为了免人工维护,采用了气泵正、反转集气、吹扫双功能;所有部件小巧,适合安装在车门附近的狭小空间内.最后对差动集气管效果、敏感探测距离进行了实验.     

碱添加量对金属离子的分布和pH变化的影响

提出了一种计算公式,定量地计算了既有氢氧化物沉淀又有氢氧配离子形成的化学反应体系中的金属离子的分布,考察了影响沉淀和配离子形成的各种因素.基于提出的公式,计算了锌、镉、铜、镍、铁（Ⅲ）、铁（Ⅱ）、铝、钙、镁的沉淀率,理论计算与实验结果一致.     

A weight function-critical plane approach for low-cycle fatigue under variable amplitude multiaxial loading

Low‐cycle fatigue data of type 304 stainless steel obtained under axial‐torsional loading of variable amplitudes are analyzed using four multiaxial fatigue parameters: SWT, KBM, FS and LKN. Rainflow cycle counting and Morrow's plastic work interaction rule are used to calculate fatigue damage. The performance of a fatigue model is dependent on the fatigue parameter, the critical plane and the damage accumulation rule employed in the model. The conservatism and non‐conservatism of predicted lives are examined for some combinations of these variables. A new critical plane called the weight function‐critical plane is introduced for variable amplitude loading. This approach is found to improve the KBM‐based life predictions.     

表面含有半导电层的高压绝缘结构的电场的有限元分析

表面半导电层结构可以均匀电场和抑制表面电晕放电,因此被广泛应用于高压电力电缆接头和高压发电机定子线圈端部绝缘中。由于表面半导电层比主绝缘层薄得多,在应用有限元法进行分析时存在着分析区域难剖分的缺点。本文经过一个简单的分析实例,提出了表面含有半导电层的高压绝缘结构电场的有限元分析方法。     

Preparation of patterned SiC and SiCN microstructures

With the development of modern science and technology, the importance of small structures or microstructures (such as the fluidic nanostructure or microreactor[1], the in- tegrate circuit in microelectronics[2], the factory in a chip[3,4], etc.) has been incarnated day by day in the fields of microelectronics, micro-optical systems, microanalytical sys- tems, microelectromechanical systems and cytobiology. And the fabrication technique (microfabrication) of the small structures has become the h…     

大型汽轮发电机主绝缘耐压和电老化试验中定子线棒端部防晕技术的研究

大型汽轮发电机在主绝缘耐压和电老化试验中,可能出现定子线棒端部闪络和防晕层过热的情况,从而损伤主绝缘,影响试验顺利进行。本文通过建立真机线棒端部的Pspice仿真模型,模拟了线棒端部绝缘表面电场分布,分析了端部闪络的原因。通过进一步的仿真研究,提出了线棒端部防晕的技术方案,并试制了线棒端部防晕装置。试验结果表明,该防晕装置可有效防止线棒端部闪络和防晕层过热。     

Performance improvement using time delays in multivariable controller design

A new controller for linear multivariable ordinary systems is suggested in which distributed delays are included in the feedback loop. A general design approach to obtain this type of controller is suggested. It is shown that the resulting closed-loop system is asymptotically stable under some sufficient conditions. Sufficient conditions are derived under which the disturbance attenuation, the robustness against parameter variations, and the time-delay stability margins are improved by the proposed controller. The state feedback tracking controller and the dual-state observer are obtained by modification of the proposed controller.