Compiled instruction set simulation

An efficient method for simulating instruction sets is described. The method allows for compiled instruction set simulation using the macro expansion capabilities found in many languages. Additionally, we show how the semantics of the C case statement allows instruction branching to be incorporated in an efficient manner. The method is compared with conventional interpreted techniques and is shown to offer considerable performance benefits.     

A study of machine-level software profile

The instruction mix of a CDC CYBER/74 computer in a university environment was monitored, and in this paper frequencies of execution for the most commonly used instructions are given. From these measurements we make a number of observations about several aspects of computing patterns. One observation is the fact that if we exclude the idle loop of the operating system, the percentage of occurrences for each type of instruction over various time intervals is constant. This fact is used to define a machine-level software profile (MLSP) for the type of machine operations in the given computing environment. It is shown that the MLSP could be used to find machine utilization and the extent to which software takes advantage of machine architecture, and as a consistent method to improve the performance of a machine configuration.     

一种基于流水线的指令Cache优化设计

在现代微处理器的设计中．Cache是整个微处理器性能的决定性因素。本文详细介绍了32位RISC微处理器“龙腾”R2中指令Cache的体系结构．着重研究了其设计和实现问题。为了提高性能,采用了预取技术和流水线技术来优化设计．仿真结果表明得到了预期的效果。     

Algorithmic Tectonics: How Cold War Era Research Shaped Our Imagination of Design

Between 1959 and 1967, the Massachusetts Institute of Technology (MIT) hosted the pioneering Computer-Aided Design Project, funded by the US Air Force. Engineers, researchers and students were brought together to re-imagine ‘design in the language of the machine’, and one of the most renowned students on this programme was Ivan Sutherland, the inventor and programmer of Sketchpad - the first interactive graphics system. Here, Daniel Cardoso Llach , an architect and researcher based at MIT, traces the influence of this Cold War project on the culture of building design and production today.     

一种新型DSP指令结构及数据通道

针对可以处理不同位宽数据的DSP结构,提出了一种提高指令编码密度的方法,使设计的DSP指令减少了32条。另外提出了两种能同时实现16bit乘法累加运算和32bit乘法累加运算的数据通道结构。对这两种数据通道都用Verilog语言进行了模拟仿真。     

纯棉特细号高密防羽绒布的织前生产工艺

介绍CJ 7.3/7.3 681/614防羽绒布织前生产工艺要点。织前各工序要注意保持纱线的弹性、均匀纱线的张力;浆纱工序要合理选择浆料,使浆膜与纱线良好地结合;正确制定各项工艺参数,显著提高纱线的耐磨性和强力,降低毛羽,才能使织造顺利进行。     

PLC开发平台的研究及实现

针对目前PLC开发平台的缺陷和不足,基于面向对象的设计思想,开发了一套全新的PLC梯形图编辑软件.介绍软件的几大功能模块,详细论述梯形图文件的存盘和读取,梯形图语言向指令表的转化并最终生成目标代码的过程,以及模拟仿真的实现.软件采用巧妙的类管理机制和灵活的扫描算法,成功实现图形语言向文本语言的转化,由于指令语言比较接近机器语言,通过解释器对指令的解释生成控制系统所能识别的代码,可以实现程序在控制系统上的运行.本软件作为一个编写PLC程序的通用开发平台,功能强大、操作简单.     

化工原理课程设计系列CAI课件的研制与应用

以化工原理课程设计系列ＣＡＩ课件为例,综述有关多媒体教学软件制作的教学设计,制作过程与方法以及实践应用效果．     

垃圾破碎机控制系统设计

基于大流量（生活垃圾可达40t/h）的垃圾破碎机,能满足在常规流量和试验阶段的大流量破碎需求。破碎机设计功率250kW,设计扭矩2x66000N·m,最大工作压力35MPa。其控制系统采用西门子PLC1500作为控制中心,配备就地显示屏、ABB变频器,通过Profinet总线通信连接在一起,经由显示屏通过Profinet总线实现破碎机的所有操作。控制系统通过采集一次仪表运行数值实现破碎机的报警、连锁,保证其正常可靠运行。采用模块化编程,优化核心算法,使破碎机的在不同工况下运行更加稳定可靠。根据上游来料量的不同,调节变频器,使垃圾破碎机运行在不同的速度,达到环保节能的目的。     

Guiding the use of collective feedback displayed on heatmaps to reduce group conformity and improve learning in Peer Instruction

Peer Instruction is an active learning method widely used in higher education, whereby students answer a series of questions twice, once before and once after peer discussion. There is an ongoing debate as to whether a collective feedback should be given after the students' initial answer, and if so, how the frequently observed group conformity can be avoided. This study examined whether guiding on the use of this feedback can reduce group conformity and improve learning using an interactive learning environment to administer a new type of quiz using graphics, and delivering collective feedback to the whole class in a novel heatmap format. In the experimental group, the teacher told the students that the answer indicated by the heatmap was not necessarily the correct one; this information was not given to students in the control group. Results revealed that guided students were less likely to adopt the (incorrect) majority answer than the non-guided students, and consequently, they were more likely to improve their learning by reaching an agreement about the correct answer through discussion with their peers. These findings suggest that guiding students in their use of collective feedback may have a crucial role in Peer Instruction.