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211.
This paper suggests a real-time method for detecting a driver’s cognitive and visual distraction using lateral driving performance measures. The algorithm adopts radial basis probabilistic neural networks (RBPNNs) to construct classification models. In this study, combinations of two driving performance data measures, including the standard deviation of lane position (SDLP) and steering wheel reversal rate (SRR), were considered as measures of distraction. Data for training and testing the RBPNN models were collected under simulated conditions in which fifteen participants drove on a highway. While driving, they were asked to complete auditory recall tasks or arrow search tasks to create cognitively or visually distracted driving periods. As a result, the best performing model could detect distraction with an average accuracy of 78.0 %, which is a relatively high accuracy in the human factors domain. The results demonstrated that the RBPNN model using SDLP and SRR could be an effective distraction detector with easy-to-obtain and inexpensive inputs.  相似文献   
212.
在决策树理论的指导下,通过信息增益的应用和公式的构造获取属性重要程度评价值,结合决策树的C5.0算法得到建筑企业的信用评价模型。经过对该模型进行测试和评价,取得了较好的预测效果。  相似文献   
213.
Traditional quality inspection based product quality evaluation method with complex process has high operating cost and requires more professional knowledge. To remove the above limitation, this paper leads product gene theory into product quality evaluation. Methods of quality influencing factors based modeling and encoding are established. Combined with similarity theory and product gene theory, a product gene similarity analysis based quality evaluation method is proposed. The proposed method is low cost, operates easily and requires less specialized knowledge. A case study is conducted to prove the correctness and feasibility of this method.  相似文献   
214.
Performance degradation and random shock are commonly regarded as two dependent competing risks for system failures. One method based on effective service age is proposed to jointly model the cumulative effect of random shock and system degradation, and the reliability model of degradation system under Nonhomogeneous Poisson processes (NHPP) shocks is derived. Under the assumption that preventive maintenance (PM) is imperfective and the corrective maintenance (CM) is minimal repair, one maintenance policy which combines PM and CM is presented. Moreover, the two decision variables, PM interval and the number of PMs before replacement, are determined by a multi-objective maintenance optimization method which simultaneously maximizes the system availability and minimizes the system long-run expect cost rate. Finally, the performance of the proposed maintenance optimization policy is demonstrated via a numerical example.  相似文献   
215.
HumanLeukocyteAntigen(HLA)system, knownashumanmajorhistocompatibilitycomplex (MHC),playsakeyroleinantigenprocessing,im muneregulationandotheraspects.HLAisalsobeen calledastransplantingantigenasaccuratetypingof HLAonbothpatientanddonorcanincreasedramat i…  相似文献   
216.
目的研究水飞蓟宾(Silibinin,SB)在体外对人膀胱癌细胞株5637增殖的抑制作用及其相关机制。方法采用MTT法观察不同浓度SB对人膀胱癌细胞株5637增殖的抑制作用;倒置显微镜下观察细胞形态变化;RT-PCR检测凋亡抑制因子Survivin的mRNA表达变化。结果MTT检测发现:随着SB浓度增加和作用时间延长,对人膀胱癌细胞株5637增殖的抑制作用增强,且各组间比较均有显著性差异(P<0.01),并呈时间-剂量依赖关系;倒置显微镜发现应用SB干预后,5637细胞体积缩小,变形,胞浆浓缩,核固缩深染;人膀胱癌细胞株5637中Survivin的mRNA表达随着SB浓度增加和时间延长相应下降。结论SB可抑制人膀胱癌细胞株5637的增殖;并下调凋亡抑制因子Survivin的mRNA表达。  相似文献   
217.
The design approach of H∞ autopilot for autonomous underwater vehicles (AUVs) is proposed. Comprised by the three sub-controllers,i.e. speed,heading and depth controllers,the designed autopilot has advantage over existing H∞ control of AUVs. The overshoot in speed,heading and depth control systems under step commands is restricted by refining the weighting function for robust stability. The dynamic performance of heading and depth control systems is improved by feeding back yaw rate and pitch angle,respecti...  相似文献   
218.
津秦铁路客运专线板式无砟轨道II型轨道板必须具备良好的绝缘性能,因此对其钢筋网制作加工要求高。介绍了Ⅱ型轨道板钢筋网制作工艺流程,具体包括热缩套管定位加工、上层和下层钢筋网片的制作等。根据工艺标准的要求,在钢筋网制作加工的工艺和设备工装上进行了优化创新,提高了轨道板钢筋网片制作加工的效率,确保了加工质量,为国内板式无砟轨道轨道板的施工提供了宝贵经验。  相似文献   
219.
采用凯氏定氮仪测定了藜、艾蒿、酸模、芦苇、狗尾草、水稻和野生大豆7种人造湿地植物的根、茎叶和植物生长土壤的含氮量.结果表明,艾蒿茎叶的含氮量为6.50 g/kg,比野生大豆、狗尾草、酸模、水稻、芦苇和藜茎叶平均含氮量高3.85 g/kg,艾蒿根的含氮量为8.66 g/kg,比藜、野生大豆、酸模、狗尾草、水稻、芦苇根的含氮量平均高3.42 g/kg,野生大豆生长的土壤含氮量为0.090 g/kg,比自然状态、芦苇、水稻和对照土壤的含氮量平均高0.03 g/kg,利用人造湿地处理污水需要植物的含氮量高和土壤的含氮量低,以便能够更有效的吸收污水中的氮.  相似文献   
220.
To quantify mechanical effects of plantar fascia and ligaments on the arch structure, a 3D finite element model of the foot was created to simulate the balanced standing posture. Four cases after individual releases of plantar fascia, spring ligament, long and short plantar ligaments were simulated respectively to compare their consequences to the predictions of the intact structure. It was founded that the foot arch didn’t collapse obviously after any individual release of these structures. As plantar fascia was released, tensions of plantar ligaments were largely increased. Long and short plantar ligaments performed mutual compensation functions.  相似文献   
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