Implications of sensor location in steam reformer temperature control

Hydrogen can be produced via steam reformation of many feedstocks. External heat sources provide the thermal energy required by the endothermic steam reformation reactions. Temperature control of the steam reformation reactor is critical to reactor performance and catalyst life. Closed-loop control systems are typically used to modulate the heat input rate based on a comparison between a set point temperature and a temperature measurement. The location of the temperature sensor relative to the heat input location is a choice made during reactor design that can have significant impact on reactor temperature control.     

巧用VSFlexGrid控件(vsFlex8.ocx)

数据网格控件是最常用的界面设计工具。本文分别介绍了VSFlexGrid控件的几种使用方法,包括通用数据记录编辑,自定义参数输入,数据自定义输出,这些方法对开发用户界面类程序有很大的实用价值。     

巧用VSFlexGrid控件(VSFlex8.ocx)

数据网格控件是最常用的界面设计工具.本文分别介绍了VSFlexGrid控件的几种使用方法,包括通用数据记录编辑,自定义参数输入,数据自定义输出,这些方法对开发用户界面类程序有很大的实用价值.     

The influence of IT: perspectives from five Australian schools

Abstract Information and Communication Technologies (ICT) are now widespread in Australian schools but with variation in how, where, when and how much they are used. Computers may be located in a computer laboratory, distributed throughout the school, or students may use their own laptop computers. IT may be a subject in its own right or ICT may be used across all areas of the curriculum. It is how ICT is used in the school setting that is important in providing students with the skills to be participate in a 'knowledge society'. This paper examines the ways in which information and communication technologies influence teaching and learning in five Australian schools. Data were gathered through observation, interviews and document analysis in schools operating at the elementary and secondary grades in relatively technology rich environments. Each of the schools participated in the Australian component of the Second Information Technology in Education Study – Module 2 (SITES-M2) of innovative pedagogical practices. Several of the studies were of specific projects where ICT was the key enabler of the learning programme. Others focused on an entire school's approach to ICT as an agent for changed approaches to learning.     

对我院生活用水的分析研究

本文针对我院生活用水和锅炉原水的水质以及使用情况进行了调查、分析和研究,指出了某些杂质带来的危害,提出了改善水质的建议和措施。     

重整装置往复压缩机运行周期短的原因及改造

分析指出重整装置往复式压缩机检修周期短的原因是：介质带液，介质带催化剂粉尘，配件使用寿命不长，气阀选型不合理。通过改造排凝线、增加凝液罐、改进配件材质、优化安装间隙、使用新型气阀、增设气缸缸套冷却水反冲洗线，机组的检修周期由原来的不足2个月提高到现在的4个月。     

Classroom furniture dimensions and anthropometric measures in primary school

The purpose of this study was to compare students' dimensions to the dimension of school furniture, in primary school, and determine whether this type of furniture is well-designed and promotes good sitting posture at school by taking into account the dimensions of the children. A total of 180 (90 male and 90 female) students, from three primary schools in Thessaloniki, Greece, participated in the study. Their ages ranged from 7 to 12 years. The following human body dimensions were measured: stature, elbow height, shoulder height, upper arm length, knee height, popliteal height and buttock-popliteal length. In addition, the dimensions were measured for four different types of chairs and five types of desks prevalent in classrooms. Finally, the anthropometric measures of the students and the furniture dimensions were compared in order to identify any incompatibility between them. The data indicate a mismatch between the students' bodily dimensions and the classroom furniture available to them. The chairs are too high and too deep and desks are also too high for the pupils. This situation has negative effects on the sitting posture of the children especially when reading and writing.     

The new method of traceability of a force-balanced piston gauge used as primary vacuum standard

The force-balanced piston gauge is a primary vacuum standard developed in the 1990s. The general principle of the instrument was first presented in Ooiwa A (Metrologia 30 (1994) 607). Non-rotating piston is connected to an electronic dynamometer and centered by means of transient gas flow in a double tapered gap between piston and cylinder. More details about it can be found in Delajoud, Girard(NCSL International Workshop and Symposium 2002; Vakuum Forschung Praxis 15 (2003) 24) and Tesar, Prazak(Vacuum 67 (2002) 307).Czech Metrology Institute developed its own method of the primary traceability of this instrument through the determination of its effective area. In this paper, there will be described experimental setup of this comparison as well as the experimental results from the traceability calibrations of the effective area in gauge and absolute mode using experimental method of hydrostatic comparison with the classical rotating piston balances and a digital non-rotating piston balance. It will, of course, include the uncertainty budget of this way of traceability and the final uncertainty of the pressure generation of the instrument.     

A Building Information Model enabled Multiple Traveling Salesman Problem for building interior patrols

During building emergencies, an effective and visible primary search plan enhances situation awareness and enables a more efficient rescue mission. The aim of the primary search during an emergency is the rapid screening of every space in the building to identify locations of victims and their conditions. Afterwards, first responders can plan for the rescue of those victims. To provide a timely draw up of interior patrol routes and assign rescue teams to conduct the primary search, this study formulates the problem as a multiple traveling salesman problem (M-TSP) where the comprehensive building interior network is given by the building information models (BIMs), while the total traveling costs (lengths) of every rescue team is minimized. To meet the requirement of real-time patrol routes optimization, we employed the branch-and-price algorithm for the enhancement of computation efficiency. In addition, a heuristic method was introduced to provide timely solutions for large-scale networks. A case study is conducted for a single-floor convention center. We utilized BIM to construct a network of nodes and arcs where the decision model requires as input, and the branch-and-price algorithm finds the optimal patrol. The resulting patrol routes can be visualized and serve as guide for rescue teams to conduct the primary search. The integrated approach proposed in this study is practical and can expedite search and rescue missions.     

基于不可见字符的主副式网页信息隐藏算法

目前国内外网页信息隐藏算法大多侧重于研究如何提高隐藏效率和扩充隐藏容量,而忽视了信息隐藏算法的安全性。为此,提出了一种基于不可见字符的主副式网页信息隐藏(PSWIH)算法,即以ASCII编码下的不可见字符为主方式实现信息隐藏,并以改变标签大小写、嵌入与待隐藏信息不相关的不可见字符、改变标签属性对顺序为副方式实现信息检测干扰。实验结果表明,相对于基于标签大小写、基于属性对顺序、基于不可见字符方法,PSWIH算法具有更好的不可感知性、抗提取性及鲁棒性。