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This paper presents the results of a study aimed at validating psychological questionnaires evaluating temperamental and personality features. It discusses their usefulness in diagnosing drivers’ aptitude for safe driving and working as professional drivers. Three psychological questionnaires were validated: the Formal Characteristics of Behaviour – Temperament Inventory (FCB-TI), the Eysenck Personality Questionnaire – Revised and Short Scale (EPQ-R (S)) and the Impulsiveness Questionnaire (IVE). Three groups of drivers (n = 246) aged 19–75 participated in the study. Group I (professional drivers; n = 96) and Group II (nonprofessional drivers; n = 75) had never been involved in road crashes, whereas Group III (nonprofessional drivers; n = 75) were offenders involved in fatal injury road crashes. Criterion-related validity, Cronbach's alpha and Guttman split-half reliability coefficient were in assessing the psychometric properties of the questionnaires. There were some significant differences between Groups II and III for most traits. However, contrary to expectations, higher Emotional Reactivity, Perseveration and lower Endurance as well as higher Neuroticism, Impulsiveness and Venturesomeness were determined for Group II than for Group III. Additionally, the temperament and personality profile of Group II turned out to be less fitted to the profile of safe drivers than that of Group III, whose profile was actually similar to that of Group I. This seems to result from a high tendency for a positive self-presentation among Group I and Group III (a significantly higher result on the Lie scale in comparison with Group II). The results suggest that if psychological tests are to decide on whether a person may be a professional driver or may drive vehicles, the three questionnaires (FCB-TI, EPQ-R(S) and IVE) do not provide a valid diagnosis of professional drivers’ aptitude because of drivers’ high tendency for positive self-presentation. However, they can be used in job counselling and in screening high-risk drivers. 相似文献
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STANISŁAW K. DUDA 《International journal of control》2013,86(5):1387-1399
This paper presents a new theory for determining dynamic output feedback of the least order for a linear, time-invariant, controllable and observable SIMO system, such that poles of the closed-loop system lie in a given region Γ in the complex plane. When some poles have prespecified stationary locations in the complex plane, dynamic output feedback is obtained in the sense that the remaining poles lie in Γ This theory applies to continuous-time as well as discrete-time systems. Here a design algorithm for complete system realization and an illustrative example are given. 相似文献
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Abstract: Numerical modelling was used to follow the moisture movement and strain in a composite system – an unrestrained, single wood panel coated with a layer of gesso, in response to cyclic sinusoidal variations in relative humidity (RH). The allowable magnitude of the variations, below which physical damage of the gesso layer on the wood does not occur over a selected time of exposure, was derived as a function of cycle duration, panel thickness and moisture diffusion configuration. The dimensional response of wood substrate becomes subject to restraint by the applied layer of gesso. The panels do not respond significantly to diurnal fluctuations or shorter irrespectively of the panel thickness. The panels respond more and more significantly when the duration of the fluctuations increases until a certain critical period at which the panel fully responds to each cycle. The analysis of the data obtained indicates that moderate RH variations within the approximate range 50 ± 15% are safe. This safe range was derived using the extremes of conservative criteria of the gesso’s fatigue fracture and assumption of worst‐case wooden substrate response. The reduction of allowable amplitude of RH cycles because of decrease in the gesso’s modulus of elasticity and thickness is discussed. 相似文献
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Jacek Szelążek 《Journal of Nondestructive Evaluation》2013,32(2):188-199
This paper discusses the development of piezoelectric ultrasonic probeheads for measurements of time of flight of subsurface or surface wave ultrasonic pulses. Sets of such probes found application in ultrasonic stress evaluation. In precise measurements of time of flight using piezoelectric transducers, the main source of time scatter proved to be variation in the condition of liquid couplant layers. The thickness of this couplant layer depends on surface roughness of the sample being evaluated. Paper describes a new configuration of probes, composed of two transmitting and four receiving probes arranged along one line, designed to reduce coupling influence on readings. Presented is comparison of readings obtained with known sets of probes and with a new one. Also presented are results of residual stress evaluation performed with various 6-transducer sets of probes on railroad rails, monoblock railroad wheels and pillars of hydraulic press. All measurements were performed in industrial conditions, without any special surface preparation. 相似文献
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W. Korcz P. Struciński K. Góralczyk A. Hernik M. Łyczewska M. Matuszak K. Czaja M. Minorczyk J. K. Ludwicki 《Indoor air》2017,27(1):128-135
Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in numerous products, from which they are emitted to the environment, including house dust. House dust is a source of human exposure to these compounds by ingestion. The aim of this article was to determine the levels of selected PBDEs in the house dust and indicate their potential sources of origin. PBDE congeners: BDE‐47, BDE‐99, BDE‐153 and BDE‐209, were analyzed in 129 samples. The geometric mean levels (and 95% CIs) of the aforementioned congeners amounted to 3.8 (3.1–4.7) ng/g, 4.5 (3.5–5.6) ng/g, 2.2 (2.1–2.4) ng/g and 345 (269–442) ng/g respectively. BDE‐209 was the dominant congener in the majority of tested samples. We found a statistically significant correlation between the concentrations of BDE‐47 and the computer operating time per day (rs – 0.18) and the living area (rs – 0.20). Statistically significant higher levels of BDE‐99 were found in homes where the floor was not replaced during the last 2 years. 相似文献
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Three polymers with excellent absorption properties were synthesized by graft polymerization: soluble starch-g-poly(acrylic acid-co-2-hydroxyethyl methacrylate), poly(vinyl alcohol)/potato starch-g-poly(acrylic acid-co-acrylamide), poly(vinyl alcohol)/potato starch-g-poly(acrylic acid-co-acrylamide-co-2-acrylamido-2-methylpropane sulfonic acid). Ammonium persulfate and potassium persulfate were used as initiators, while N,N′-methylenebisacrylamide was used as the crosslinking agent. The molecular structure of potato and soluble starch grafted by synthetic polymers was characterized by means of Fourier Transform Infrared Spectroscopy (FTIR). The morphology of the resulting materials was studied using a scanning electron microscope (SEM). Thermal stability was tested by thermogravimetric measurements. The absorption properties of the obtained biopolymers were tested in deionized water, sodium chroma solutions of various concentrations and in buffer solutions of various pH. 相似文献
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