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91.
Rotter T 《Applied ergonomics》1982,13(3):213-215
This article concerns the problem of acoustic work conditions on railway locomotives. The objective results of sonometric surveys in locomotive cabins are compared with subject data received from locomotive crews obtained by means of a specific questionnaire 'The Subjective Estimation of Noise'. The analysis touched 9 type of locomotives; steam, diesel and electric engines. We asked drivers of different age groups and with varying lengths of professional service for their opinions The aim of the investigation was to determine the following points: 1. to analyse the drivers' subjective estimation of the noise in the locomotive cabins; 2. to define length of time for which the driver remains under the influence of the noise after finishing work; 3. to investigate the question of perception and understanding of sounds and vocal signals used in the locomotive. These problems are a small part of the general plan to improve work conditions on the Polish National Railways. 相似文献
92.
This paper reports on the results of a detailed parametric study into the effects of patch loads on the stresses in thin-walled circular steel silos. Firstly, an analysis of the effects of a typical patch load on the stresses in a silo wall is presented. The results show that the stresses set up are complex and that they could potentially lead to failure of the silo by either elastic buckling or plastic collapse. A parametric study is then conducted which examines the effects of varying the circumferential width of the patch load, the vertical extent of the load, the point of application of the load and the pressure distribution within the load. The results show that the circumferential width of the applied load and the pressure distribution both strongly affect the form and magnitude of the stresses produced in the silo wall. The magnitudes of stresses in the silo wall were found to vary almost linearly with the vertical extent of the patch load. 相似文献
93.
Investigated 100 college student scores and reliabilities on the Rotter Incomplete Sentences Blank (ISB) for the years 1965, 1970, and 1977. Results indicate (a) no significant differences among the years studied, (b) significant differences between student scores in the present study and the original ISB norms (J. B. Rotter and J. E. Rafferty, 1950), and (c) high interscorer reliabilities of rescoring protocols after many years. (1 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
95.
Angular dependence of sampling modulation transfer function 总被引:1,自引:0,他引:1
Sampling modulation transfer function (MTF) as defined in Park et al. [Appl. Opt. 23, 2527-2582 (1984)] as an x and y sampling can be generalized for image data not along x and y directions. For a given sampling lattice (such as in a laser printer, a scene projector, or a focal-plane array), we construct a two-dimensional sampling MTF based on the distance between nearest samples in each direction. Because the intersample distance depends on direction, the sampling MTF will be best in the directions of highest spatial sampling and poorer in the directions of sparse sampling. We compare hexagonal and rectangular lattices in terms of their equivalent spatial frequency bandwidth. We filter images as a demonstration of the angular-dependent two-dimensional sampling MTF. 相似文献
96.
Lihi Adler‐Abramovich Zohar A. Arnon XiaoMeng Sui Ido Azuri Hadar Cohen Oded Hod Leeor Kronik Linda J. W. Shimon H. Daniel Wagner Ehud Gazit 《Advanced materials (Deerfield Beach, Fla.)》2018,30(5)
One major challenge of functional material fabrication is combining flexibility, strength, and toughness. In several biological and artificial systems, these desired mechanical properties are achieved by hierarchical architectures and various forms of anisotropy, as found in bones and nacre. Here, it is reported that crystals of N‐capped diphenylalanine, one of the most studied self‐assembling systems in nanotechnology, exhibit well‐ordered packing and diffraction of sub‐Å resolution, yet display an exceptionally flexible nature. To explore this flexibility, the mechanical properties of individual crystals are evaluated, assisted by density functional theory calculations. High‐resolution scanning electron microscopy reveals that the crystals are composed of layered self‐assembled structures. The observed combination of strength, toughness, and flexibility can therefore be explained in terms of weak interactions between rigid layers. These crystals represent a novel class of self‐assembled layered materials, which can be utilized for various technological applications, where a combination of usually contradictory mechanical properties is desired. 相似文献
97.
Wenwen Lin Jiangang He Kyle M. McCall Constantinos C. Stoumpos Zhifu Liu Ido Hadar Sanjib Das Hsien-Hau Wang Bi-Xia Wang Duck Young Chung Bruce W. Wessels Mercouri G. Kanatzidis 《Advanced functional materials》2021,31(13):2006635
Room temperature semiconductor detector (RTSD) materials for γ-ray and X-ray radiation are in great demand for the nonproliferation of nuclear materials as well as for biomedical imaging applications. Halide perovskites have attracted great attention as emerging and promising RTSD materials. In this contribution, the material synthesis, purification, crystal growth, crystal structure, photoluminescence properties, ionizing radiation detection performance, and electronic structure of the inorganic halide perovskitoid compound TlPbI3 are reported on. This compound crystallizes in the ABX3 non-perovskite crystal structure with a high density of d = 6.488 g·cm–3, has a wide bandgap of 2.25 eV, and melts congruently at a low temperature of 360 °C without phase transitions, which allows for facile growth of high quality crystals with few thermally-activated defects. High-quality TlPbI3 single crystals of centimeter-size are grown using the vertical Bridgman method using purified raw materials. A high electrical resistivity of ≈1012 Ω·cm is readily obtainable, and detectors made of TlPbI3 single crystals are highly photoresponsive to Ag Kα X-rays (22.4 keV), and detects 122 keV γ-rays from 57Co radiation source. The electron mobility-lifetime product µeτe was estimated at 1.8 × 10–5 cm2·V–1. A high relative static dielectric constant of 35.0 indicates strong capability in screening carrier scattering and charged defects in TlPbI3. 相似文献
98.
Pawel Rotter 《Multimedia Tools and Applications》2014,72(1):667-685
In this article we propose a method for information retrieval based on relational Multi-Criteria Decision Making. We assume that a user cannot define precise search criteria so that these criteria must be found based on the user’s assessment of several sample alternatives (‘alternatives’ here are database records, e.g. images). This situation is common in Content-based Image Retrieval, where it is easier for a user to indicate relevant images than to describe a proper query, especially in formal language. The proposed algorithm for the elicitation of criteria is based on ELECTRE III—a method originally designed for ranking a set of alternatives according to defined criteria. In our algorithm, however, the direction of reasoning is reversed: we start with several sample alternatives that have been assigned a rank by the user and then we select criteria that are compatible (in the sense of ELECTRE methodology) with the user’s preferences expressed on a sample set. Then, having determined the user’s criteria, we apply classical ELECTRE III to retrieve the relevant solutions from the database. We implemented the method in Matlab and tested it on the Microsoft Cambridge Image Database. 相似文献
99.
UV‐Light‐Driven Oxygen Pumping in a High‐Temperature Solid Oxide Photoelectrochemical Cell 下载免费PDF全文
Georg Christoph Brunauer Bernhard Rotter Gregor Walch Esmaeil Esmaeili Alexander Karl Opitz Karl Ponweiser Johann Summhammer Juergen Fleig 《Advanced functional materials》2016,26(1):120-128
A solid‐state photoelectrochemical cell is operated between 400 and 500 °C under 365 nm UV light. The cell consists of a photovoltaic part, based on a La0.8Sr0.2CrO3/SrTiO3 junction, and an electrochemical part including a zirconia solid electrolyte with a shared (La,Sr)FeO3 electrode. The photovoltaic cell part leads to open circuit voltages up to 920 mV at 400 °C. Upon UV light, this driving force is used in the electrochemical part of the cell to pump oxygen from low to high partial pressures, i.e., to convert radiation energy to chemical energy. This demonstrates the feasibility of high‐temperature photoelectrochemical cells for solar energy storage. The detailed characterization of the different resistance contributions in the system by DC and AC methods reveals the parts of the cell to be optimized for finally achieving high‐temperature photoelectrochemical water splitting. 相似文献
100.
Hadar Ben-Yoav Tal Amzel Marek Sternheim Shimshon Belkin Adi Rubin Yosi Shacham-Diamand Amihay Freeman 《Electrochimica acta》2011,(26):9666
This paper presents an integrated whole-cell biochip system where functioning cells are deposited on the solid micro-machined surfaces while specially designed indium tin oxide electrodes that can be used to apply controllable electric fields during various stages; for example during cell deposition. The electrodes can be used also for sensing currents associated with the sensing mechanisms of electrochemical whole-cell biosensors. In this work a new approach integrating live bacterial cells on a biochip using electrophoretic deposition is presented. The biomaterial deposition technique was characterized under various driving potentials and chamber configurations. An analytical model of the electrophoretic deposition kinetics was developed and presented here. The deposited biomass included genetically engineered bacterial cells that may respond to toxic material exposure by expressing proteins that react with specific analytes generating electrochemically active byproducts. In this study the effect of external electric fields on the whole-cell biochips has been successfully developed and tested. The research hypothesis was that by applying electric fields on bacterial whole-cells, their permeability to the penetration of external analytes can be increased. This effect was tested and the results are shown here. The effect of prolonged and short external electric fields on the bioelectrochemical signal generated by sessile bacterial whole-cells in response to the presence of toxins was studied. It was demonstrated that relatively short 10 ms external DC electric pulse improves the performance of bacterial biosensors by 15% relative to un-biased biosensors. The application of prolonged 1 h external alternating electric fields deteriorated the whole-cell performance in the presence of toxins. In this paper we present the electrode apparatus and methods, as well as the characterization results, e.g. signal vs. time and induction factor, of such chips and discussing the highlight and problems of this new concept. 相似文献