Increased seasonality in Middle East temperatures during the last interglacial period

The last interglacial period (about 125,000 years ago) is thought to have been at least as warm as the present climate. Owing to changes in the Earth's orbit around the Sun, it is thought that insolation in the Northern Hemisphere varied more strongly than today on seasonal timescales, which would have led to corresponding changes in the seasonal temperature cycle. Here we present seasonally resolved proxy records using corals from the northernmost Red Sea, which record climate during the last interglacial period, the late Holocene epoch and the present. We find an increased seasonality in the temperature recorded in the last interglacial coral. Today, climate in the northern Red Sea is sensitive to the North Atlantic Oscillation, a climate oscillation that strongly influences winter temperatures and precipitation in the North Atlantic region. From our coral records and simulations with a coupled atmosphere-ocean circulation model, we conclude that a tendency towards the high-index state of the North Atlantic Oscillation during the last interglacial period, which is consistent with European proxy records, contributed to the larger amplitude of the seasonal cycle in the Middle East.     

高性能高应变InGaAs量子阱脊型波导半导体激光器

介绍了利用分子束外延系统生长高应变InGaAs量子阱半导体激光器材料, 采用脉冲阳极氧化技术制作脊型波导半导体激光器. 4 μm条宽脊型波导半导体激光器在室温下单面连续输出功率达到50 mW. 腔长600 μm时, 器件阈值电流密度为300 A/cm2. 在100 mA电流下, 激光器的峰值波长为1.19 μm, 激光器的最大斜率效率为0.45 W/A. 在20℃至100℃温度下, 激光器的特征温度为129 K.     

INTELLIGENT SECURITY SYSTEMS ENGINEERING FOR MODELING FIRE CRITICAL INCIDENTS： TOWARDS SUSTAINABLE SECURITY

An intelligent security systems engineering approach is used to analyze fire and explosive critical incidents, a growing concern in urban communities. A feed-forward back-propagation neural network models the damages arising from these critical incidents. The overall goal is to promote fire safety and sustainable security. The intelligent security systems engineering prediction model uses a fully connected multilayer neural network and considers a number of factors related to the fire or explosive incident including the type of property affected, the time of day, and the ignition source. The network was trained on a large number of critical incident records reported in Toronto, Canada between 2000 and 2006. Our intelligent security systems engineering approach can help emergency responders by improving critical incident analysis, sustainable security, and fire risk management.     

熵和对称损失函数下MINQUE和简单估计的比较(英)

在熵损失和对称损失函数下，研究了多元线性模型协方差矩阵的MINQUE估计和简单估计的比较问题，其中多元线性模型的设计矩阵和离散矩阵可以不满秩.并证明了，在熵损失函数下，MINQUE估计总是优于简单估计.     

协方差矩阵的MINQUE和简单估计的比较

在二次损失函数下,作者研究了多元线性模型协方差矩阵的MINQUE估计和简单估计的比较问题,其中多元线性模型的设计矩阵和离散矩阵可以不满秩,得到了一个充分和必要条件。     

多层次测试包:一种用于系统层设计的C/C++门组件层故障模拟的测试包

提出了一种多层次测试包(MLT)用来测试系统层的设计.该包可以被用来测试由门组件层C+ +代码和C+ +复杂函数构成的混合设计.电路部件在高功能层上被描述,而C+ +函数被用来描述门组件层的部件.测试工具可用高层C+ +函数的模拟来用于门组件层部件.使用这个包避免了将被测试部件转换成硬件描述语言,同时也提高了测试应用程序的模拟速度.