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1.
In recent years the use of new technical equipment and the Internet by middle-aged people has increased. This paper presents middle-aged people’s (45 years old or older) usage of new technical equipment and analyses how their (2704 persons) symptoms are associated with the equipment. Over 70% of Finland’s middle-aged population use mobile phones daily and less than 30% use desktop computers at leisure. For example, over 80% of middle-aged people had sometimes or often experienced pain, numbness or aches in the neck and about 70% had aches in the hip and lower back. The use of new technical equipment among the group of people who are outside working life was smaller than the people’s usage in general. In the future, when new technical equipment is developed, it is important to take into account, that people (outside working life) do not use, e.g., the Internet as much as people in general. The working environment will be much more ergonomic also at home and the Internet services will be easy to use for almost everyone, even those who have little experience or knowledge of computers and the Internet.  相似文献   
2.
ABSTRACT

An automatic system for measuring photocurrent of electrodes as a function of excitation wavelength and electrode potential is described. Applications to a chemically modified transparent Sn02 electrode and an oxide-covered tantalum electrode are shown.  相似文献   
3.
Samples of a low alloy steel piping material taken from the full scale corrosion fatigue test loop of the Heissdampfreaktor (HDR) plant have been tested at 240°C in high oxygen reactor water. The small-scale specimens (CT25) were exposed to a similar loading spectrum to that which has been used in the full-scale corrosion fatigue tests at the HDR-plant. During the autoclave tests cyclic crack growth rates were determined. Fracture surface investigations were performed not only for the laboratory test specimens but also for the fracture surface of a sample taken from the HDR test loop piping after the full scale test. In this paper the autoclave testing results and fracture surface observations are presented and compared to those obtained in the HDR piping tests.  相似文献   
4.
A joint pressure vessel integrity research programme involving three partners is being carried out during 1990–1995. The partners are the Central Research Institute of Structural Materials “Prometey” from Russia, IVO International Ltd (IVO) from Finland, and the Technical Research Centre of Finland (VTT). The main objective of the research programme is to increase the reliability of the VVER-440 reactor pressure vessel safety analysis. This is achieved by providing material property data for the VVER-440 pressure vessel steel, and by producing experimental understanding of the crack behaviour in pressurized thermal shock loading for the validation of different fracture assessment methods. The programme is divided into four parts: pressure vessel tests, material characterization, computational fracture analyses, and evaluation of the analysis methods. The testing programme comprises tests on two model pressure vessels with artificial axial outer surface flaws. The first model vessel had circumferential weld seam at the mid-length of the vessel. A special embrittling heat treatment is applied to the vessels before tests to simulate the fracture toughness at the end-of-life condition of a real reactor pressure vessel. The sixth test on the first model led to crack initiation followed by arrest. After the testing phase, material characterization was performed. Comparison of calculated and experimental data generally led to a good correlation, although the work is being continued to resolve the discrepancies between the measured initiation and arrest properties of the material.  相似文献   
5.
The effect of metallurgical variables on the two most important crack growth mechanisms - stable crack growth by environmentally assisted cyclic crack growth and unstable crack growth by cleavage - in light water reactor pressure vessel steels is evaluated. The analyses are based on micromechanisms of fracture and sensitivity analysis, when applicable. Metallurgical variables considered are non-metallic inclusions and carbides as well as other parameters through their effects on yield strength and other mechanical properties.  相似文献   
6.
Mental overload directly affects safety in aviation and needs to be alleviated. Speech recordings are obtained non-invasively and as such are feasible for monitoring cognitive load. We recorded speech of 13 military pilots while they were performing a simulator task. Three types of cognitive load (load on situation awareness, information processing and decision making) were rated by a flight instructor separately for each flight phase and participant. As a function of increased cognitive load, the mean utterance-level fundamental frequency (F0) increased, on average, by 7 Hz and the mean vocal intensity increased by 1 dB. In the most intensive simulator flight phases, mean F0 increased by 12 Hz and mean intensity, by 1.5 dB. At the same time, the mean F0 range decreased by 5 Hz, on average. Our results showed that prosodic features of speech can be used to monitor speaker state and support pilot training in a simulator environment.  相似文献   
7.
Reviews the book, The Cambridge handbook of literacy by David R. Olsen and Nancy Torrance (see record 2009-03310-000). This handbook sets out to examine literacy in its widest sense; to examine both the visual signs for linguistic forms, and the social and personal uses of these signs, from the mundane to the literary, both historically and currently. It aims to address a gap that it identifies in the literature: the lack of an authoritative text on literacy as a field in itself, and in providing such a text, further aims to provide scope for future interdisciplinary work. The book is divided into five parts (Literacy as a Scientific Subject, Literacy and Language, Literacy and Literatures, Literacy and Society, and Literacy and Education), described in the preface as representing “transformations in our understanding of literacy.” Overall, the handbook feels more like a set of separate chapters than an integrated work, with very little cross-referencing across the chapters. This book includes many examples of chapters that build from generally known linguistics, cognitive and developmental theories to make their ideas accessible. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Within the IAEA coordinated programme on optimizing of reactor pressure vessel surveillance programmes and their analysis, phase 3, a specially tailored radiation sensitive correlation monitor material, a Japanese steel plate with code designation JRQ, a French forging material (FFA) and a Japanese forging material (JFL) were selected for the investigations to be carried out in Finland.Based on the evaluation of the experimental results it was demonstrated that dynamic fracture toughness transition shift is equivalent to the Charpy-V shift, but the static fracture toughness transition shift may be considerably larger than the dyanamic shift. Thus, Charpy-V is not suitable for estimating the static fracture toughness transition shift.These findings have a strong impact upon the design of future surveillance programmes.  相似文献   
9.
Conductive polymers have the ability to capture radicals and have become in focus for antioxidant applications of food packaging or biomedical applications. Unfortunately, the conducting polymers such as polypyrrole are difficult to suspense in solution after chemical or electrochemical polymerization. Chitosan, as a natural polymer from chitin, can be dissolved in diluted acetic acid solutions. In the present study, composites suspensible in diluted acetic acid solutions have been produced by the chemical polymerization of pyrrole in chitosan solution using ammonium persulfate (APS) as the oxidant. FTIR and UV–Vis measurements did identify an attachment of polypyrrole to chitosan.In order to optimize the activity and stability of the composites, the ratios of APS: polypyrrole: chitosan were analyzed. The chitosan–polypyrrole composites were formed as membranes (coatings); impedance measurements indicated their conductivity to be in the range of 10?3–10?7 S cm?1. The antioxidant (radical scavenger activity) properties were determined by the di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH) assay. The radical scavenger activity of the composites was found renewable by means of electrochemical cycling.  相似文献   
10.
This study examines the impact of the Learning Strategies Curriculum (LSC), an adolescent reading intervention program, on 6th- and 9th-grade students' reading comprehension and strategy use. Using a randomized treatment–control group design, the study compared student outcomes for these constructs for 365 students who received daily instruction in 6 LSC strategies and 290 students who did not receive intervention instruction. After 1 school year, 6th-grade students who received intervention instruction significantly outperformed students in the control group on a standardized measure of reading comprehension and reported using problem-solving strategies in reading to a greater extent than students in the control group. There were no significant differences between 9th grade intervention and control groups in reading comprehension or strategy use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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