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{\it Objective.} Comparisons of the results of a multidimensional criterion-referenced vocational assessment (CMVA) were performed between a group of patients with chronic pain (group P; n = 86) and individuals working (group W; n...
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{\it Objective.} Comparisons of the results of a multidimensional criterion-referenced vocational assessment (CMVA) were performed between a group of patients with chronic pain (group P; n = 86) and individuals working (group W; n = 106). The participants had experience of five job categories. {\it Methods.} The participants' capability to work was assessed from the aspects of personal factors, background data, present work experience, personal and work environmental factors probably influencing work capacity and capacity to perform occupations. Eleven instruments comprising 407 items were used. {\it Results.} The results of the comparisons suggest that group P participants' work capacity was significant decreased by how they perceived their present work experience (X^2; p < 0.001), self-assessed or observed capability to perform daily and work occupations (t; p < 0.000). Among the factors which probably influenced their work capability, group P participants significantly (t; p < 0.05) more often used confrontive, emotive, palliative and covert coping strategies and had attained work and other life values to a less extent. Moreover, group P participants perceived that they had had a significant (t; p < 0.000) higher degree of psychosocial demands and more strain incurred from the psychosocial work environment.
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The Stratospheric Observatory for Infrared Astronomy (SOFIA) has recently concluded a set of engineering flights for observatory performance evaluation. These in-flight opportunities are viewed as the first comprehensive assessmen...
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The Stratospheric Observatory for Infrared Astronomy (SOFIA) has recently concluded a set of engineering flights for observatory performance evaluation. These in-flight opportunities are viewed as the first comprehensive assessment of the observatory's performance and are used to guide future development activities, as well as to identify additional observatory upgrades. Pointing stability was evaluated, including the image motion due to rigid-body and flexible-body telescope modes as well as possible aero-optical image motion. We report on recent improvements in pointing stability by using an active mass damper system installed on the telescope. Measurements and characterization of the shear layer and cavity seeing, as well as image quality evaluation as a function of wavelength have also been performed. Additional tests targeted basic observatory capabilities and requirements, including pointing accuracy, chopper evaluation, and imager sensitivity. This paper reports on the data collected during these flights and presents current SOFIA observatory performance and characterization.
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Economists rely frequently on instrumental variables estimation to overcome biases that endogenous explanatory variables cause in ordinary least squares estimation. However, traditional instrumental variables estimators, such as t...
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Economists rely frequently on instrumental variables estimation to overcome biases that endogenous explanatory variables cause in ordinary least squares estimation. However, traditional instrumental variables estimators, such as two-stage least squares and limited information maximum likelihood estimation, can suffer persistent estimator biases and size-of-test biases in even very large samples if the instruments used are large in number or are only weakly correlated with an endogenous explanatory variable. This paper reviews strategies for grappling with weak instruments and with large numbers of instruments in linear regression models.
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Clinicians are frequently challenged by endodontically treated teeth that have obstructions, such as hard impenetrable pastes, separated instruments, silver points or posts in their root canals. Intracanal separation of endodontic...
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Clinicians are frequently challenged by endodontically treated teeth that have obstructions, such as hard impenetrable pastes, separated instruments, silver points or posts in their root canals. Intracanal separation of endodontic instruments may hinder cleaning and shaping procedures within the root canal system, with a potential impact on the outcome of the treatment. This article presents an overview of the literature in relation to management of separated intracanal instruments and a case report of separated instrument retrieval.
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Current and voltage instrument transformers are essential elements of the power system. They work like transformers but do not transmit power. Their task is to accurately transform currents or voltages during system operation, whi...
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Current and voltage instrument transformers are essential elements of the power system. They work like transformers but do not transmit power. Their task is to accurately transform currents or voltages during system operation, which are then used for measurement and protection. These devices are very precise, and their accuracy is defined by the IEC/CEN standards. Instrument transformers are located at all transformer stations, specialized high-voltage and high-power laboratories, and testing and teaching laboratories. Therefore, the design requirements are very different depending on their type (current, voltage, or combined), function (measuring, protection), and operating voltage (high, medium, and low). The requirements concern not only the operation but also the strength of the insulation system and, sometimes, the mechanical strength.
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The Stratospheric Observatory for Infrared Astronomy (SOFIA), the largest airborne observatory in the world, is in full operation capability since February 2014 and is currently completing its Observing Cycle 6 Program. The first ...
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The Stratospheric Observatory for Infrared Astronomy (SOFIA), the largest airborne observatory in the world, is in full operation capability since February 2014 and is currently completing its Observing Cycle 6 Program. The first four years of operation have provided the opportunity to assess the high-level observatory’s technical performance and to identify additional observatory upgrades. Since the start of routine operations, performance and productivity in several areas of the observatory, including science, operations and engineering, have been tracked by metrics and statistics. In this paper we present the general observatory technical performance as the observatory has reached its maturity and has served the science community with over 2900h of scientific observations.
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In this review, we look back upon the literature, which had the GREGOR solar telescope project as its subject including science cases, telescope subsystems, and post-focus instruments. The articles date back to the year 2000, when...
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In this review, we look back upon the literature, which had the GREGOR solar telescope project as its subject including science cases, telescope subsystems, and post-focus instruments. The articles date back to the year 2000, when the initial concepts for a new solar telescope on Tenerife were first presented at scientific meetings. This comprehensive bibliography contains literature until the year 2012, i.e., the final stages of commissioning and science verification. Taking stock of the various publications in peer-reviewed journals and conference proceedings also provides the "historical" context for the reference articles in this special issue of Astronomische Nachrichten/Astronomical Notes.
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In this paper, the present status of the development of the design of the European Solar Telescope is described. The telescope is devised to have the best possible angular resolution and polar metric performance. maximizing the th...
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In this paper, the present status of the development of the design of the European Solar Telescope is described. The telescope is devised to have the best possible angular resolution and polar metric performance. maximizing the throughput of the whole system. To that aim, adaptive optics and multi-conjugate adaptive optics are integrated in the optical path. The system will have the possibility to correct for the diurnal variation of the distance to the turbulence layers, by using several deformable mirrors, conjugated at different heights. The present optical design of the telescope distributes the optical elements along the optical path in such a way that the instrumental polarization induced by the telescope is minimized and independent of the solar elevation and azimuth. This property represents a large advantage for polarimetric measurements. The ensemble of instruments that are planned is also presented.
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