SAm级防撞活动护栏碰撞仿真分析

针对目前高速公路中央分隔带开口处活动护栏防撞等级较低的问题,提出了一种SAm级混凝土活动护栏及一种新型连接装置。基于有限元的方法,建立车辆与护栏的碰撞模型,通过LS-DYNA对车辆与护栏碰撞过程进行求解,根据不同车型的碰撞结果分别在缓冲,阻挡和导向性能上对护栏的安全性能进行评价,其中小型车辆与护栏碰撞后的OIV(Occupant Impact Velocity)值<12 m/s,ORA(Occupant Ridedown Acceleration)值<20 g且车辆没有驶出导向框;大型车辆与护栏碰撞后没有发生穿越、骑跨等现象且车辆没有驶出导向框,均满足护栏安全性能评价标准。     

Post李超代数结构的性质

通过post李超代数的定义, 讨论post李超代数结构的基本性质, 给出post李超代数的一些存在性结果, 并利用post李超代数可构造LR超代数和左对称超代数, 给出交换post李超代数结构的相关结果.     

Study on the Centralization Strategy of the Blood Allocation Among Different Departments within a Hospital

By far, the researches on how to distribute blood products among different departments in hospital have not been further studied, though the problem of blood shortage and wastage that caused by improper blood allocation is severe, which may endanger patient’s lives and impose considerable costs on hospitals. In order to solve this problem, this paper mainly studies on how to distribute the blood items among different departments within a hospital and investigates the allocation approach with the novel management method by centralizing the inventory of several different departments. By integrating the blood inventory requirements of some departments, the hospital could reduce the rate of blood shortage and wastage effectively, release the pressure of the occupancy of resources and reduce the bullwhip effect of blood products. This paper illustrates the centralization principle in hospital and formulates the mixed integer programming model to work out the optimal allocation network scheme and the optimal inventory setting for every department. And the results of the numerical example demonstrate that this centralization method could considerably reduce blood shortage and wastage in hospital by about 72% and 90% respectively. Furthermore, it could decrease the total cost by about 108,540 RMB a month on blood supply chain management in the hospital and improve the effect of some certain surgeries by transfusing the fresh blood to patients.     

Long-term increases in clutch size in common snapping turtles (Chelydra serpentina) and diamondback terrapins (Malaclemys terrapin)

Clutch size (CS) is a well-studied life history characteristic, and optimal egg size theory predicts that CS should correlate positively with reproductive investment. Turtles are good subjects for studies of reproductive strategies because few turtle species exhibit parental care; therefore quantifying their short-term reproductive investment is mostly limited to measuring egg size and number. Clutch size is usually reported as an average value for each turtle population, and where CS variation is noted, it is usually attributable to variation in adult body size. In two long-term studies of ecologically dissimilar species we detected a dramatic increase in CS in a common snapping turtle (Chelydra serpentina) population and in a diamondback terrapin (Malaclemys terrapin) population. It is unknown whether these changes are due to either variation in adult body size or resource availability; but the temporal patterns we observed have apparently never been reported previously. These trends remain unexplained and should be explored further.     

Notch Effect and Frequency Compensation of Dual-Sensor OBC Data in Shallow Water

Reverberation is significant in shallow water and produces obvious notches in OBC spec-tra. It also degrades the quality of sections and increases the difficulty of processing and interpretation. This ...     

矿井索车的优化设计

对矿井索车优化设计中的几个关键性问题进行了探讨，包括驱动轮和尾轮的设计、钢丝绳直径的选择计算、托绳轮间距的确定、绳卡的设计、张紧力和张紧行程的确定、互锁问题的解决等。     

西文期刊回溯建库中几个重要项目的著录

在实践的基础上，从期刊的出版日期、出版周期、卷、期、年、月及其他标识、ISSN、增刊、出版者以及期刊的历史发展等方面对西文期刊机读目录的标准化著录问题进行了探讨。     

NIPA类共聚温敏水凝胶中水的状态和耐热性

用N-异丙基丙烯酰胺（NIPA）与丙烯酸钠（SA）及甲基丙烯酸钠（SMA）共聚合成了两个系列的水凝胶，研究了共聚组成与水凝胶基本性质的关系，并用示差扫描量热法（DSC）和热失重法（TG）研究了此类水凝胶中水的状态和耐热性。