may incur significant bandwidth for executing more com- plicated search queries such as multiple-attribute queries. In order to reduce query overhead, KSS (keyword-set search) by Gnawali partitions the index by a set ...may incur significant bandwidth for executing more com- plicated search queries such as multiple-attribute queries. In order to reduce query overhead, KSS (keyword-set search) by Gnawali partitions the index by a set of keywords. However, a KSS index is considerably larger than a standard inverted index, since there are more word sets than there are individual words. And the insert overhead and storage overhead are obviously un- acceptable for full-text search on a collection of documents even if KSS uses the distance window technology. In this paper, we extract the relationship information between query keywords from websites’ queries logs to improve performance of KSS system. Experiments results clearly demonstrated that the improved keyword-set search system based on keywords relationship (KRBKSS) is more efficient than KSS index in insert overhead and storage overhead, and a standard inverted index in terms of communication costs for query.展开更多
大约80%的水上交通事故涉及人为因素,驾驶员疲劳是船舶交通事故发生的关键原因之一。近年来,基于脑电图(Electroencephalogram,EEG)的驾驶员疲劳检测技术的发展,有助于快速准确地识别驾驶员的疲劳程度。然而,由于EEG信号的敏感性和个体...大约80%的水上交通事故涉及人为因素,驾驶员疲劳是船舶交通事故发生的关键原因之一。近年来,基于脑电图(Electroencephalogram,EEG)的驾驶员疲劳检测技术的发展,有助于快速准确地识别驾驶员的疲劳程度。然而,由于EEG信号的敏感性和个体差异,影响驾驶员疲劳检测的准确性。该试验在船舶模拟器中进行,收集多个受试者的脑电信号。选取与疲劳相关的脑前额叶的3个通道脑电信号进行预处理,并提取基于EEG的多种特征,例如平均绝对值(Mean Absolute Value,MAV)、标准差(Standard Deviation,SD)、均方根(Root Mean Square,RMS)和香农熵(Shannon Entropy,SE)。基于卡罗林斯卡嗜睡量(Karolinska Sleepiness Scale,KSS)表将驾驶员的疲劳分为清醒、中等和疲劳等3个程度。将多种分类算法的分类准确率进行比较,双向长短期记忆网络(Bi-Long Short Term Memory,Bi-LSTM)分类器效果最佳,分类准确率达到88.63%。结果表明:该方法在研究船舶驾驶员跨个体的三分类问题中能获得显著的效果。展开更多
目的研究髌骨置换对全膝关节置换术疗效的影响。方法 2010年9月至2010年11月在宁夏医科大学总医院骨科行全膝关节置换术的膝关节骨性关节炎的患者,共69例,随机分为两组即髌骨置换组和非置换组,置换组35例,非置换组34例。术后随访6周、3...目的研究髌骨置换对全膝关节置换术疗效的影响。方法 2010年9月至2010年11月在宁夏医科大学总医院骨科行全膝关节置换术的膝关节骨性关节炎的患者,共69例,随机分为两组即髌骨置换组和非置换组,置换组35例,非置换组34例。术后随访6周、3个月、6个月、12个月,比较两组之间在knee score评分、knee function score评分、髌骨评分、术后膝前痛发生率、影像学表现是否有统计学差异。结果两组在术后随访时knee score评分之间无明显统计学差异。两组在术后随访6个月、12个月knee function score评分有明显统计学差异,P<0.05。在12个月髌骨评分置换组高于非置换组,P<0.05。置换组较非置换组术后膝前痛发生率明显降低,P<0.05。置换组与非置换组术后平均股胫角、髌韧带比值、髌骨倾斜角无明显差异,P>0.05。结论全膝关节置换术行髌骨置换可以改善knee function score评分、髌骨评分及降低术后膝前痛的发生率。展开更多
基金Project supported by the National Natural Science Foundation of China (No. 60221120145) and Science & Technology Committee of Shanghai Municipality Key Project (No. 02DJ14045), China
文摘may incur significant bandwidth for executing more com- plicated search queries such as multiple-attribute queries. In order to reduce query overhead, KSS (keyword-set search) by Gnawali partitions the index by a set of keywords. However, a KSS index is considerably larger than a standard inverted index, since there are more word sets than there are individual words. And the insert overhead and storage overhead are obviously un- acceptable for full-text search on a collection of documents even if KSS uses the distance window technology. In this paper, we extract the relationship information between query keywords from websites’ queries logs to improve performance of KSS system. Experiments results clearly demonstrated that the improved keyword-set search system based on keywords relationship (KRBKSS) is more efficient than KSS index in insert overhead and storage overhead, and a standard inverted index in terms of communication costs for query.
文摘大约80%的水上交通事故涉及人为因素,驾驶员疲劳是船舶交通事故发生的关键原因之一。近年来,基于脑电图(Electroencephalogram,EEG)的驾驶员疲劳检测技术的发展,有助于快速准确地识别驾驶员的疲劳程度。然而,由于EEG信号的敏感性和个体差异,影响驾驶员疲劳检测的准确性。该试验在船舶模拟器中进行,收集多个受试者的脑电信号。选取与疲劳相关的脑前额叶的3个通道脑电信号进行预处理,并提取基于EEG的多种特征,例如平均绝对值(Mean Absolute Value,MAV)、标准差(Standard Deviation,SD)、均方根(Root Mean Square,RMS)和香农熵(Shannon Entropy,SE)。基于卡罗林斯卡嗜睡量(Karolinska Sleepiness Scale,KSS)表将驾驶员的疲劳分为清醒、中等和疲劳等3个程度。将多种分类算法的分类准确率进行比较,双向长短期记忆网络(Bi-Long Short Term Memory,Bi-LSTM)分类器效果最佳,分类准确率达到88.63%。结果表明:该方法在研究船舶驾驶员跨个体的三分类问题中能获得显著的效果。
文摘目的研究髌骨置换对全膝关节置换术疗效的影响。方法 2010年9月至2010年11月在宁夏医科大学总医院骨科行全膝关节置换术的膝关节骨性关节炎的患者,共69例,随机分为两组即髌骨置换组和非置换组,置换组35例,非置换组34例。术后随访6周、3个月、6个月、12个月,比较两组之间在knee score评分、knee function score评分、髌骨评分、术后膝前痛发生率、影像学表现是否有统计学差异。结果两组在术后随访时knee score评分之间无明显统计学差异。两组在术后随访6个月、12个月knee function score评分有明显统计学差异,P<0.05。在12个月髌骨评分置换组高于非置换组,P<0.05。置换组较非置换组术后膝前痛发生率明显降低,P<0.05。置换组与非置换组术后平均股胫角、髌韧带比值、髌骨倾斜角无明显差异,P>0.05。结论全膝关节置换术行髌骨置换可以改善knee function score评分、髌骨评分及降低术后膝前痛的发生率。
