Information technology and road transport industry: how does IT affect the lorry driver?

A quasi-experimental design was used to study the effect of on board computer-systems (OBC-systems) on the Dutch lorry drivers' psychosocial work environment (i.e., control and demands) and coinciding mental health (i.e., need for recovery after work) and job attitudes (i.e., organisational commitment). The intervention group (n = 26) started working with an OBC-system between 1998 and 2000 and was compared with two matched reference groups (n = 26 in both groups). All participants were from a cohort of 650 drivers who participated in a prospective study on occupational stress and health. All outcome variables were quantified by standardised and validated questionnaires. Results showed that the application of OBC-systems negatively affected the drivers' job control and organisational commitment. However, OBC-systems did not influence the drivers' psychological job demands and need for recovery after work. Accordingly, it is concluded that the application of OBC-systems negatively affects the lorry driver's psychosocial work environment and job attitudes.     

Self-enhancing and self-defeating ego orientation: Relations with task and avoidance orientation, achievement, self-perceptions, and anxiety.

Recent research in motivation has identified 2 main goal orientations: task orientation and ego orientation. Two studies of 6th- and 8th-grade Norwegian students tested the prediction that there are different dimensions of ego orientation (self-defeating and self-enhancing), that they may be separated from other goal orientations, and that they relate differently to academic achievement, self-concept, self-efficacy, self-esteem, anxiety, and intrinsic motivation. Results from both studies supported the predictions. The correlation between self-defeating and self-enhancing ego orientation was small, and these constructs had different relations to other variables in the study. Self-defeating ego orientation was associated with high anxiety and was negatively related to achievement and self-perceptions. Self-enhancing ego orientation was positively related to achievement, self-perceptions, and intrinsic motivation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Expert systems and their application in sensory evaluation

One of the main issues facing sensory evaluation is that very few sensory professionals are competent in all the relevant disciplines. Moreover, the standard of training available is generally inadequate. Expert systems may offer a partial solution to this problem. Seven possible applications of expert systems and artificial intelligence in sensory evaluation are briefly outlined.     

A high-order Lagrangian-decoupling method for the incompressible Navier-Stokes equations

In this paper we present a high-order Lagrangian-decoupling method for the unsteady convection diffusion and incompressible Navier-Stokes equations. The method is based upon Lagrangian variational forms that reduce the convection-diffusion equation to a symmetric initial value problem, implicit high-order backward-differentiation finite difference schemes for integration along characteristics, finite element or spectral element spatial discretizations and mesh-invariance procedures and high-order explicit time-stepping schemes for deducing function values at convected space-time points. The method improves upon previous finite element characteristic methods through the systematic and efficient extension to high-order accuracy and the introduction of a simple structure-preserving characteristic-foot calculation procedure which is readily implemented on modern architectures. The new method is significantly more efficient than explicit-convection schemes for the Navier-Stokes equations due to the decoupling of the convection and Stokes operators and the attendant increase in temporal stability. Numerous numerical examples are given for the convection-diffusion and Navier-Stokes equations for the particular case of a spectral element spatial discretization.     

Food poisoning associated with pumilacidin-producing Bacillus pumilus in rice

Food poisoning caused by other Bacillus species than B. cereus has been described, but the toxins involved have rarely been isolated. Endospores will survive heat treatment and will germinate and multiply in cooked foods producing toxins under appropriate conditions. We describe a small food poisoning outbreak where three people became ill after a dinner in a Chinese restaurant. Acute symptoms including dizziness, headache, chills and back pain developed during the meal, and a few hours later they got stomach cramps and diarrhoea which lasted for several days. Cooked, reheated rice was the prime suspect of the food poisoning, and from the rice large numbers of Bacillus pumilus were isolated. The isolated B. pumilus strain was found to produce a complex of lipopeptides known as pumilacidins with the highest amounts produced at 15 degrees C. This is the first report on isolation of a pumilacidin-producing B. pumilus strain from food implicated in food poisoning and characterization of the organism and the toxin complex involved.     

Surveying and digital workflow in energy performance retrofit projects using prefabricated elements

Due to the need for improving the energy efficiency of existing buildings, various methods for energy retrofitting are being developed. One such initiative is the TES Energy Façade project, a joint European academia and industry project under the umbrella of the WoodWisdom Net research platform. The project has developed a systematic approach for using prefabricated timber-framed elements that can be assembled in front of an existing façade. The TES approach requires a detailed and precise documentation of the as-built/as-maintained conditions of the existing façade. This paper discusses the approach for the surveying and documentation of a building's existing state and the need to establish a continuous digital chain that encompasses the various project stages from the survey to the site assembly of the elements. Technologies such as 3D laser scanning and BIM are efficient tools in the process but are not yet sufficiently developed to handle all of the challenges in renewal and retrofit projects.     

Design of embedded TCAM based longest prefix match search engine

The content addressable memory (CAM) based solutions are very useful in network applications due to its high speed parallel search mechanism. This paper presents a novel Ternary CAM (TCAM) based NAND Pseudo CMOS–Longest Prefix Match (NPC–LPM) search engine. The proposed system provides a simple hardware based solution using novel 11T TCAM cell structures and NPC word line technique, for network routers. The experiments were performed on 256 × 128 NPC–LPM system under 0.13 μm technology. The simulation result shows that the proposed design provides low power dissipation of 5.78 mW and high search speed of 315 MSearches/s under 1.3 V supply voltage. The presented NPC–LPM system meets the speed requirement of Optical Carrier (OC) 3072 with line-rate of 160 Gb/s in Ethernet networking and IPv6 protocol. The experimental results also show that the proposed system improves power-performance by 65%.     

水电站地下厂房洞室顶拱的形成与锚固

在水电站地下洞室顶锚固设计中,认识岩石顶拱的形成与结构特征,又了解锚固的增强效果十分重要。应用古典楔块拱理论分析了地下洞室顶拱形成和拱的作用,根据极限平衡分析对顶拱锚杆加固进行了评价,并以小浪底工程地下厂房洞顶为例进行了分析,结合数值模型,针对锚杆和锚索对顶拱加固的不同效果进行了比较论证。结果表明:地下厂房洞顶自然拱结构在开挖后基本形成;系统灌浆锚杆加固是必要的;整个洞顶安装系统张拉锚索应谨慎,因其对顶拱稳定作用不大,且可能有负面影响。在水电站地下洞室顶锚固设计中,认识岩石顶拱的形成与结构特征,又了解锚固的增强效果十分重要。应用古典楔块拱理论分析了地下洞室顶拱形成和拱的作用,根据极限平衡分析对顶拱锚杆加固进行了评价,并以小浪底工程地下厂房洞顶为例进行了分析,结合数值模型,针对锚杆和锚索对顶拱加固的不同效果进行了比较论证。结果表明:地下厂房洞顶自然拱结构在开挖后基本形成;系统灌浆锚杆加固是必要的;整个洞顶安装系统张拉锚索应谨慎,因其对顶拱稳定作用不大,且可能有负面影响。     

Aerodynamic Focusing of Nanoparticles: I. Guidelines for Designing Aerodynamic Lenses for Nanoparticles

Abstract

This article describes the challenges in focusing nanoparticles (< 30 nm) into tightly collimated beams, and provide guidelines for designing aerodynamic lens systems for nanoparticles. The major difficulties of focusing nanoparticles arise from their low inertia and high diffusivity. Because of their low inertia, nanoparticles tend to closely follow gas streamlines; their high diffusivities lead to beam broadening and diffusional deposition. We have identified the minimum particle size that can be focused to the axis with a single lens when diffusion is neglected, assuming that the flow is continuum and subsonic. We show that lighter carrier gases are preferred for focusing small particles, and that multiple lenses operating at suboptimal Stokes numbers can be designed to focus particles smaller than was recognized previously. There exists a maximum pressure under which particles can be optimally focused, while particle diffusion and pumping requirements are minimized. Finally, we describe the procedure for designing aerodynamic lens systems for focusing nanoparticles, and present a case study of designing a single aerodynamic lens to focus 5 nm particles.