等截面垂直管道中气粉流的临界管长

考虑重力和摩擦力的影响，建立了描述垂直管道中气粉流行为的数学模型，采用马赫数检验法，确定了产生摩擦壅塞时的临界管长，计算表明，当气粉流以不同方式喷入相同的冶金熔池时，底吹垂直管道比顶吹垂直管道需要更大的临界管长。     

电能质量问题及对策

概述了电能质量问题的产生及日益引起关注的原因，介绍了国际电工委员会(IEC)和电气与电子工程师协会(IEEE)对电能质量的定义，并针对电能质量问题提出了具体对策。     

Karyotypes of seven species of bats from Thailand (Chiroptera,Mammalia)

Summary Karyotypes ofMyotis siligorensis, Myotis mystacinus, Pipistrellus pulveratus, Tylonycteris robustula, Miniopterus schreibersi fuliginosus, Hipposideros fulvus andAselliscus stoliczkanus from Thailand are investigated.Acknowledgment. The authors are very grateful to Dr N. Ratanawarabhan, Mrs S. Sittilert, P. Noonpakdee and S. Kuanchalern of Thailand Institute of Scientific and Technological Research for their valuable advice and assistance during our field survey in Thailand.     

Visual categorization shapes feature selectivity in the primate temporal cortex.

The way that we perceive and interact with objects depends on our previous experience with them. For example, a bird expert is more likely to recognize a bird as a sparrow, a sandpiper or a cockatiel than a non-expert. Neurons in the inferior temporal cortex have been shown to be important in the representation of visual objects; however, it is unknown which object features are represented and how these representations are affected by categorization training. Here we show that feature selectivity in the macaque inferior temporal cortex is shaped by categorization of objects on the basis of their visual features. Specifically, we recorded from single neurons while monkeys performed a categorization task with two sets of parametric stimuli. Each stimulus set consisted of four varying features, but only two of the four were important for the categorization task (diagnostic features). We found enhanced neuronal representation of the diagnostic features relative to the non-diagnostic ones. These findings demonstrate that stimulus features important for categorization are instantiated in the activity of single units (neurons) in the primate inferior temporal cortex.