Representation and uniformization of algebraic transductions

This paper explores different means of representation for algebraic transductions, i.e., word relations realized by pushdown transducers. The relevance of this work lies more in its point of view rather than any particular result. We are aiming at giving specific techniques for obtaining, or perhaps explaining, decompositions of algebraic (and incidentally, rational) relations, relying solely on their “machine” definition rather than some complex algebraic apparatus. From this point of view, we are hoping to have demystified the heavy formalism employed in the present literature. Some of the novelties of our work are: the use of “stack languages” and “embeddings,” which eliminate the need of arbitrary context-free languages in our characterizations, the study of uniformizations for algebraic transductions and the use of the so-called stack transductions for exposing the anatomy of pushdown transducers.This work was supported by the Natural Science and Engineering Research Council of Canada grants R220259 and OGP0041630.     

宝鸡民营钛工业发展现状

介绍了宝鸡民营钛工业在新材料、新技术、新设备、新应用方面的进展,提供了市场需求与发展前景方面的相关信息,并对中小型钛加工企业的发展提出建议。     

浅谈高层医院自动消防系统和日常管理

从高层医院所应具备自动消防系统和在高层医院日常管理中 ,加强消防安全教育 ,建立管理制度 ,主动发挥“人”主观能动性的两个方面 ,具体阐述了高层医院的消防安全工作     

发展靠改革 改革求创新——访上海烟草工业印刷厂俞志康厂长

从中央对“十一五”规划的部署来看,我国的发展又进入了一个新的历史阶段。规划强调改变经济的增长方式,提高资源利用率,调整经济增长与资源环境制约之间的矛盾,继续实施产业结构的调整,对企业兼并改组的力度还将加强,钢铁、石油、石化、烟草等均在其列。占国家税收重头的烟草业,自2003年就迎来一次“地震”式的重组。2006年1月11日,国家烟草专卖局又宣布,正式启动“打造十大烟草航母集团”的计划,将对现有44家烟草企业进行整合,组建成以品牌为支撑的十大烟草航母集团。这对长期以来依靠烟草企业而生存发展的烟草印刷企业来说,如何面对这种改组,并规划好自身的发展,采取哪些应对策略与措施,也就成了那些不甘寂寞,且仍想稳操胜券的烟印企业领导们关注的焦点。其实,在钢铁、石油、石化以及其他大型企业集团长期庇护下的印刷企业又何止少数?这些企业的领导人也该从“手捧铁饭碗,稳坐太师椅”的状态中有所觉醒、有所思考吧?所以这次我们采访上海烟草印刷厂领导的目的,说白了,绝不仅仅是为了报道上海烟印自强不息的光辉篇章,而是通过这一报道,给面临行业整合改组的印企领导们奉上一道醒酒菜。毕竟在葡萄美酒前自我陶醉的好景不会太久了,还是尽快作好优胜劣汰的竞争准备吧。     

NUMERICAL SIMULATION OF PARTICLE SEPARATION IN AN OIL-SAND SEPARATOR

ＮＯＴＡＴＩＯＮＳＡ　Ａｒｅａｏｆｉｎｌｅｔ ,ｍ2ａ　Ｃｅｎｔｒｉｆｕｇａｌａｃｃｅｌｅｒａｔｉｏｎ ,ｍ2 /ｓｉ　Ｇｒｉｄｏｆａｘｉａｌｄｉｒｅｃｔｉｏｎｍｌ 　ＭａｘｉｍｕｍｇｒｉｄｎｕｍｂｅｒｏｆｒａｄｉａｌｄｉｒｅｃｔｉｏｎＱ　Ｆｌｕｉｄｍａｓｓｒａｔｅ ,ｍ3/ｓＲｃ 　Ｍａｘｉｍｕｍｒａｄｉｕｓｏｆｃｙｃｌｏｎｅ ,ｍＲｅ　Ｒｅｙｎｏｌｄｓｎｕｍｂｅｒｒ　Ｄｉｍｅｎｓｉｏｎｌｅｓｓｒａｄｉａｌｄｉｓｔａｎｃｅｔ　Ｄｉｍｅｎｓｉｏｎｌｅｓｓｔｉｍｅｕ　Ｄｉｍｅｎｓｉｏｎｌｅｓｓａｘｉａｌｖｅｌｏｃ…     

全球电信业发展一览

介绍了世界主要国家和地区电信业的发展情况。     

Generating topological structures for surface models

Rapid prototyping has imposed new requirements on the processing of CAD models. To manufacture an object directly, the model must correspond to a real object and thus represent a closed volume. Its boundary must be continuous and closed, and no cracks or improper intersections are allowed. CAD models cannot always meet these requirements, especially when they are constructed by a surface modeler. The algorithm discussed analyzes surface models and generates a topological structure for them that meets rapid prototyping requirements for a closed volume with a continuous, closed boundary     

采集系统中存储技术的研究

随着光纤技术在嵌入式领域中的应用,通信数据量不断增加,高速采集网络上的数据并正确地存储到磁盘上已成为整个系统的瓶颈。本文从系统基本功能模块出发结合生产者/消费者(Producer-Consumer)模型,对多线程并发、直接读写扇区、异步I/O等技术在系统中的应用进行分析;对系统模型进行抽象,用数学方法对系统进行可行性分析。实验表明,数据采集系统中采用多线程多缓冲的方式在性能上有一定的提高。     

Fast full‐color reflective display via photoluminescent enhancement

Reflective displays are advantageous in applications requiring low power or daylight readability. However, there are no low‐cost reflective technologies capable of displaying bright colors. By employing photoluminescence to more efficiently use ambient light, we created a prototype display that provides bright, full color in a simple, low‐cost architecture. This prototype includes a novel electrokinetic shutter, a layer that incorporates patterned luminescent red, green, and blue sub‐pixel elements, and a novel optical out‐coupling scheme. The luminescent elements convert otherwise‐wasted portions of the incident spectrum to light in the desired color band, resulting in improved color saturation and lightness. This prototype provides a color gamut that is superior to competing reflective display technologies that utilize color filters in single‐layer side‐by‐side sub‐pixel architectures. The current prototype is capable of switching in <0.5 s; future displays based on an alternative electro‐optic shutter technology should achieve video rate operation. A transflective version of this technology has also been prototyped. The transflective version utilizes its backlight with a power efficiency that is at least three times that of a conventional liquid crystal display. These photoluminescence‐based technologies enable a host of applications ranging from low‐power mobile products and retail pricing signage to daylight readable signage for outdoor advertising segments.