黄臀鹎禁食和夜间能量物质消耗的研究

该文报道分布于昆明地区的黄臀鹎 Pycnonotus xanthorrhous 在禁食和四季夜间能量物质——脂肪、蛋白质和糖的消耗情况. 结果表明, 在人为禁食条件下黄臀鹎的存活时间仅19小时, 死亡时躯脂降低79%, 去脂飞翔肌干重降低46%, 肝糖降低96%. 在夜间黄臀鹎消耗大量的储存脂肪, 并以冬季的消耗量最大. 肝糖提供的能量极少. 在繁殖期和换羽期, 储存的飞翔肌蛋白质在夜间大量分解以提供鸟体的需要。

Integrated avalanche diode for 600 v Trench IGBT over-voltage protection

Avalanche multiplication has been one of the major destructive failure mechanisms in IGBTs; in order to avoid operating an IGBT under abnormal conditions, it is desirable to develop peripheral protecting circuits monolithically integrated without compromising the operation and performance of the IGBT. In this paper, a monolithically integrated avalanche diode (D av) for 600V Trench IGBT over-voltage protection is proposed. The mix-mode transient simulation proves the clamping capability of the D av when the IGBT is experiencing over-voltage stress in unclamped inductive switching (UIS) test. The spread of avalanche energy, which prevents hot-spot formation, through the help of the avalanche diode feeding back a large fraction of the avalanche current to a gate resistance (R G) is also explained. © 2011 IEEE.

盘qu属鱼类口吸盘的形态分化及其意义

具大、小吸盘的两个类群是盘qu鱼类在演化进程中分化成的两个自然类群, 它们为适应不同的栖息环境, 吸盘的微观结构和须的长短等进一步分化, 分化途径在两个类群各不相同。图版2参9

On-line policy optimisation of spoken dialogue systems via live interaction with human subjects

Statistical dialogue models have required a large number of dialogues to optimise the dialogue policy, relying on the use of a simulated user. This results in a mismatch between training and live conditions, and significant development costs for the simulator thereby mitigating many of the claimed benefits of such models. Recent work on Gaussian process reinforcement learning, has shown that learning can be substantially accelerated. This paper reports on an experiment to learn a policy for a real-world task directly from human interaction using rewards provided by users. It shows that a usable policy can be learnt in just a few hundred dialogues without needing a user simulator and, using a learning strategy that reduces the risk of taking bad actions. The paper also investigates adaptation behaviour when the system continues learning for several thousand dialogues and highlights the need for robustness to noisy rewards. © 2011 IEEE.