安全仪表系统的功能安全设计

针对安全仪表系统（SIS）的产品开发,分析了应用于石化领域的安全仪表系统的基本特性、冗余结构和常见产品类型。在介绍IEC 61508标准的基础上,提出了安全仪表系统产品开发过程中整体安全生命周期、产品硬件及安全相关软件的功能安全设计方法;最后以SIL2级压力变送器为例,着重阐述了SIS系统结构设计和故障诊断覆盖要求。     

Structures and spectroscopic properties of nonperipherally and peripherally substituted metal-free phthalocyanines: a substitution effect study based on density functional theory calculations

The molecular structures, molecular orbitals, atomic charges, electronic absorption spectra, and infrared (IR) and Raman spectra of a series of substituted metal-free phthalocyanine compounds with four (1, 3, 5, 7) or eight (2, 4, 6, 8) methoxyl (1, 2, 5, 6) or methylthio groups (3, 4, 7, 8) on the nonperipheral (1-4) or peripheral positions (5-8) of the phthalocyanine ring are studied by density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations. The calculated structural parameters and simulated electronic absorption and IR spectra are compared with the X-ray crystallography structures and the experimentally observed electronic absorption and IR spectra of the similar molecules, and good agreement between the calculated and experimental results is found. The substitution of the methoxyl or methylthio groups at the nonperipheral positions of the phthalocyanine ring has obvious effects on the molecular structure and spectroscopic properties of the metal-free phthalocyanine. Nonperipheral substitution has a more significant influence than peripheral substitution. The substitution effect increases with an increase in the number of substituents. The methylthio group shows more significant influence than the methoxyl group, despite the stronger electron-donating property of the methoxyl group than the methylthio group. The octa-methylthio-substituted metal-free phthalocyanine compounds have nonplanar structures whose low-lying occupied molecular orbitals and electronic absorption spectra are significantly changed by the substituents. The present systematical study will be helpful for understanding the relationship between structures and properties in phthalocyanine compounds and designing phthalocyanines with typical properties.     

Fast,Sub‐pixel Antialiased Shadow Maps

Solving aliasing artifacts is an essential problem in shadow mapping approaches. Many works have been proposed, however, most of them focused on removing the texel‐level aliasing that results from the limited resolution of shadow maps. Little work has been done to solve the pixel‐level shadow aliasing that is produced by the rasterization on the screen plane. In this paper, we propose a fast, sub‐pixel antialiased shadowing algorithm to solve the pixel aliasing problem. Our work is based on the alias‐free shadow maps, which is capable of computing accurate per‐pixel shadow, and only incurs little cost to extend to sub‐pixel accuracy. Instead of direct supersampling the screen space, we take facets to approximate pixels in shadow testing. The shadowed area of one facet is rapidly evaluated by projecting blocker geometry onto a supersampled 2D occlusion mask with bitmasks fusion. It provides a sub‐pixel occlusion sampling so as to capture fine shadow details and features. Furthermore, we introduce the silhouette mask map that limits visibility evaluation to pixels only on the silhouette, which greatly reduces the computation cost. Our algorithm runs entirely on the GPU, achieving real‐time performance and is an order of magnitude faster than the brute‐force supersampling method to produce comparable 32× antialiased shadows.     

CAPPFramework工程化实施研究

ＣＡＰＰ应用框架与开发平台（ＣＡＰＰＦｒａｍｅｗｏｒｋ）是一个以面向对象ＣＡＰＰ知识库系统为核心的通用交互式ＣＡＰＰ应用支撑软件。ＣＡＰＰＦｒａｍｅｗｏｒｋ的实施已成为ＣＡＰＰＦｒａｍｅｗｏｒｋ推广应用的关键,这是由工艺设计问题的特性所决定的。文章对ＣＡＰＰＦｒａｍｅｗｏｒｋ实施的工程化管理进行研究,建立了ＣＡＰＰＦｒａｍｅｗｏｒｋ实施质量保证体系,以提高ＣＡＰＰＦｒａｍｅ－ｗｏｒｋ应用系统的工程化程度。     

一种适用于中频电源简单可靠的双极PWM技术

介绍一种已应用于陀螺罗经电源系统的双极脉宽调制（ＢＰＷＭ）技术。它利用ＥＰＲＯＭ和一些常规数字电路就可实现,不需要单片机和ＣＰＵ。这一简单而可靠的双极ＰＷＭ技术,为电源系统的良好性能打下了基础。     

构件模板动态实例化技术的研究与应用

本文介绍了构件体系结构下的模板动态实例化技术,该技术将构件模板与补充语义分离处理,引入动态实例化操作,为需求改变的动态配置提供了实用和有效的手段。     

PDUIMS--基于持久存储的用户界面管理系统的设计与应用

用户界面作为软件系统的重要组成部分,在软件整个生命周期中具有独特的地位。软件质量控制的核心在于用户界面的有效、可扩展、高适应度的管理、常规的界面管理位于源码一级,对于大规模企业级应用将带来许多弊端文中介绍了一个利用动态加载和持久存储实现的面向商务处理的用户界面管理系统ＰＤＵＩＭＳ,该系统通过功能描述数据表存储用户界面实现了集中统一的数据库工程化界面管理和发布,对于应用语义提供了分离机制实例表明了该     

传统制器之道——中国汽车造型设计之本土化根源

在现代汽车制造业中,造型设计已经成为了现代汽车高速发展的强大推动力。后工业文明时代的汽车造型设计更加重视对文化的继承和发展,融入本土制器之道的设计已成为设计的主流意识之一。     

高石粉含量人工砂的应用研究

石粉含量对人工砂品质、外加剂性能、混凝土配合比及其性能均有影响。试验研究表明,石粉含量与细度模数成线性反比;石粉含量的增加增大了人工砂比表面积,提高了保水性;同时也增强了外加剂的吸附能力,削弱了外加剂塑化及保塑性能。石粉含量的波动对混凝土单位用水量、砂率等配合比参数影响显著,但通过配合比的设计、调整,混凝土工作及力学性能不会出现明显的波动。