运用记忆规律科学地组织中专计算机教学

本文根据笔者的计算机教学经验论述了如何把记忆规律运用到中专计算机教学中,以科学地组织教学,提高学生学习的效率。     

基于80C196KB的线阵CCD高速采集系统

文章介绍了一种基于单片机80C196KB的线阵CCD高速采集系统。系统采用线阵CCD专用A/D芯片MAX1101和直接存储器控制方式解决了高速采集(A/D变换)与慢速CPU之间的矛盾。     

“To be recorded” analysis in reverse-mode automatic differentiation

The automatic generation of adjoints of mathematical models that are implemented as computer programs is receiving increased attention in the scientific and engineering communities. Reverse-mode automatic differentiation is of particular interest for large-scale optimization problems. It allows the computation of gradients at a small constant multiple of the cost for evaluating the objective function itself, independent of the number of input parameters. Source-to-source transformation tools apply simple differentiation rules to generate adjoint codes based on the adjoint version of every statement. In order to guarantee correctness, certain values that are computed and overwritten in the original program must be made available in the adjoint program. For their determination we introduce a static data-flow analysis called “to be recorded” analysis. Possible overestimation of this set must be kept minimal to get efficient adjoint codes. This efficiency is essential for the applicability of source-to-source transformation tools to real-world applications.     

Simulation as a tool for optimizing memory accesses on NUMA machines

Due to the inherent non-uniformity in the memory system, programmers and users of non-uniform memory access (NUMA) machines have to take special care of the memory performance of their applications. This paper discusses a variety of potential improvements with respect to cache misses, cache invalidations, and inter-node communication. This study is based on the simulation tool SIMT, which models the memory hierarchy in detail and is capable of providing complete, accurate information about all dynamic memory references. This information can be used to analyze the memory access behavior of applications and thereby forms the basis for any optimization with respect to memory accesses.     

高端SOC芯片的外部存储器接口设计

文章以一款24位高端SOC的设计经历，简单描述了SOC芯片的外部存储器接口设计以及实现方式。该方案的一个特点是：提出了在不同类型存储器存储空间之间可以进行存储空间的切换。并以SRAM的接口设计为例简单的介绍了如何进行外部存储器的接口设计。     

论OLAP的三种实现技术

OLAP(On-LineAnalyticalProcessing)是数据仓库系统的主要应用,它支持复杂的分析操作,侧重决策支持。文章从数据的存储方式,钻取操作,数据更新,和性能上研究了OLAP的三种实现技术ROLAP(RelationalOLAP),MOLAP(MultidimensionalOLAP)HO-LAP(HybridOLAP)的不同和三种实现技术的适用范围。     

对称多处理SMP中进程间通讯对操作系统的要求

分析了支持对称多处理(SMP)的Linux操作系统对共享内存机制、共享存储和消息传递两种并发程序设计模型的实现,以两种代表机制Omni OpenMP和MPICH为对象,以及SystemV IPC下的共享存储空间实现,介绍并分析了Linux对SMP中进程间通讯的支持与实现,并从中推出了SMP中进程间通讯对支持SMP的操作系统的要求,为理解和设计SMP操作系统提供了实例和思路．     

From short-term memory to semantics-a computational model

Clinical disorders of language, known as aphasia, cause impaired comprehension of speech in written and spoken forms. This impairment is due to the patients inability to process semantics that arise from sequence independent co-occurrence of words with content in a short-term memory (STM) of preceding words. If W_i is the immediately forthcoming word in input to the patient, STM, in the context of this disorder, consists of a window, STM_Win, that contains the k words that immediately precede W_i. We use a generative approach to model semantics that ensue from the co-occurrence of W_i and STM_Win, and view these semantics as the output of a random process with parameters . The model uses supervised learning to maximize the likelihood of , given labeled content in STM_Win. Experimental validation on standard text classification data sets gives an accuracy that is comparable to, or better than, that obtained using support vector machines (SVMs).     

怀久与精神考古设计——设计作为情感的表现形式探讨

随着经济和审美的提高,对于器物的情感,人们更多地从实用价值移情于观念价值。设计师在从事设计工作时,设计的责任被更多的消费因素提起,因为消费者进行消费时对器物注入了更多文化内涵的要求,设计慢慢成为了一种情感的表现形式。本文试图从怀久与精神考古设计概念的缘起以及如何在物品的细节体现这个概念的角度来探讨设计的怀久与精神考古,希冀设计更多地注重情感需求。     

存储器模拟分析

模拟分析是IC设计的重要组成部分,以存储器为例,介绍了模拟分析的基本流程及方法。