250m大跨度连续刚构桥的结构分析

该文以本池沟特大桥设计为例,分别进行了结构静力计算和动力计算,按照目前实行的JTGD62-2004规范进行了成桥阶段各项检算。计算结果表明:由于本池沟大桥桥面宽度较窄,通过预应力钢束的优化,实现了全预应力混凝土设计的要求。自振特性分析结果表明动力性能良好。研究成果对大跨度连续刚构桥的设计具有一定的借鉴作用。     

Theoretical,Simulation and Experimental Analysis of Microfluidic Droplet Generation and Recovering Process with Applications in Frying Oil Assessments

The research on microfluidic droplet size prediction has been extensive and fruitful, while the droplet deforming process has been seldom studied. In this paper, a frying-oil-assessing microfluidic device was designed to study the droplet deforming and recovering processes, which were dominated by channel geometry, flow rates, sheath flow viscosity and interfacial tension of the two phases. Theoretical expressions of the deforming process and its extreme value were obtained for the first time, supported by simulation and experiments. Theoretical, simulation and experimental results indicated that the steady-state droplet length could be a useful parameter for frying oil assessment.     

Research of Clinical Named Entity Recognition Based on Bi-LSTM-CRF

Electronic Medical Records (EMR) with unstructured sentences and various conceptual expressions provide rich information for medical information extraction. However, common Named Entity Recognition (NER) in Natural Language Processing (NLP) are not well suitable for clinical NER in EMR. This study aims at applying neural networks to clinical concept extractions. We integrate Bidirectional Long Short-Term Memory Networks (Bi-LSTM) with a Conditional Random Fields (CRF) layer to detect three types of clinical named entities. Word representations fed into the neural networks are concatenated by character-based word embeddings and Continuous Bag of Words (CBOW) embeddings trained both on domain and non-domain corpus. We test our NER system on i2b2/VA open datasets and compare the performance with six related works, achieving the best result of NER with F1 value 0.853 7. We also point out a few specific problems in clinical concept extractions which will give some hints to deeper studies.     

颅内前循环动脉瘤的外科治疗

自 1990年 2月至 1998年 8月 ,共收治颅内前循环动脉瘤 32例 ,15例行血管内栓塞术(其中 1例栓塞失败改作手术治疗 ) ;17例显微镜下直视手术 ,术后死亡 1例。随访 2 8例 ,2 2例恢复良好 ,1例植物生存 ,2例偏瘫 ,2例动眼神经麻痹 ,1例癫痫。对前循环动脉瘤的诊断、治疗方法的选择及手术要点作了讨论。     

基于核Logistic回归的乐器音乐辨识

基于统计学习的音频分类具有理论基础坚实,实现机制简单等特点受到广泛关注并被很多音频分类系统所采用。本文对核Logistic回归算法(KLR)进行了深入分析,提出基于KLR的音频分类器设计方法,应用其解决同类型的乐器音乐分类问题。结合所采集的小提琴中提琴和大提琴的音乐信号样本进行了分类仿真试验,并与传统的Logistic回归(LR)和支持向量机(SVM)进行对比。结果表明,核Logistic回归模型具有较为优越的分类性能和非线性处理能力。     

退火遗传算法优化的神经网络在销售预测中的应用

将遗传算法(GA)和模拟退火(SA)优化的神经网络应用到制造企业的销售预测中.预测采用三层前馈神经网络,其中神经网络的连接权重和节点阈值的确定使用GA和SA算法相结合的优化学习策略.GA采用实数编码, 把要确定的神经网络连接权重和节点阈值作为基因串.实例数值计算表明该种算法的神经网络的学习速度和预测精度都比单纯BP算法得出的结果好,适合于制造企业的销售预测.     

基于遗传算法和模拟退火算法的制造企业伙伴选择

针对制造企业的虚拟企业问题建立了伙伴选择的多目标模型.为了更好地解决该问题,通过分析遗传算法和模拟退火算法的各自特性,提出了将遗传算法和模拟退火算法两者结合来进行求解.同时,通过实例仿真结果表明了该模型和算法的可行性和正确性.     

摩托车后轮轴断裂原因分析

由于应力集中、组织粗大、碳层过厚、瞬时冲击、轴向窜动和交变扭矩等原因,摩托车后轴易在端部、尾部和连接部等薄弱部位发生脆性断裂和疲劳断裂。通过分析,找出原因,并对供应商提出了工艺改进建议。     

城市公交车队运营规模的规划分析

本文研究公交运营规模,包括车型和车队、发车间距等的规划分析.在对运营者费用、用户费用二者关系分析的基础上,考虑了乘客需求分布的时变特征,对车队运营的费用最优问题进行了讨论,并通过算例予以说明.     

上海长江大桥主桥斜拉桥双箱梁节段的三维空间屈曲

上海长江大桥主通航孔桥斜拉桥的桥面结构为中间箱形联系梁连接的分离式双箱梁钢结构体系,具有十分复杂的空间效应,而局部屈曲问题是钢箱梁设计中的一个关键问题。因此,对双箱梁节段的局部屈曲分析是非常有必要的。运用大型结构分析软件SAP2000的三维板壳单元进行建模,模型边界的荷载施加考虑了结构总体分析的真实受力工况,分析得到了一些双箱梁节段的三维屈曲模态及屈曲系数,并且提出了一些对结构设计有价值的建议。