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Abstrakt

Assumptions of the major political and legal documents of the European Union, dedicated to energy efficiency and energy performance of buildings provide the Member States with relevant instruments supporting improvement of the ambient air qualityby dissemination of measures reducing energy demand and promotion of renewable energysources. Mainstreaming EU legislation into national regulations constitutes initial stage of the long term process of supporting implementation of energy efficiency measures. Experience in the improvement of energy performance of the residential buildings revealslimited efficiency of the measures implemented up to date, which results in significantair pollution of Polish cities. The national Action Plans had adopted a limited scope of recommendations included in the EU directives, hence the process meets significant challenges.The article describes adaptation of the relevant EU directives as well as the National Urban Policy in terms of the potential to effectively address faced challenges.
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Spośród parametrów detonacyjnych materiału wybuchowego (MW) z punktu widzenia użytkownika najbardziej istotnym jest jego „siła”, czyli zdolność do wykonania przez niego pracy. Działanie MW po detonacji w otworze strzałowym jest procesem szybkim i skomplikowanym: najpierw występuje ciśnienie detonacji powodujące zmiażdżenie skały w sąsiedztwie MW oraz powstanie spękań, następnie ciśnienie produktów detonacji powoduje rozszczelnienie spękań i urobienie skały. W artykule przedstawiono metody oznaczania zdolności do wykonania pracy przez materiały wybuchowe do użytku cywilnego (dynamit i saletrol) stosowane w akredytowanym w Laboratorium Badań Materiałów Wybuchowych i Zapalników Elektrycznych Kopalni Doświadczalnej Barbara Głównego Instytutu Górnictwa, tj. metodę bloku ołowianego i metodę wahadła balistycznego. Celem badań było stwierdzenie istnienia zależności między wartościami zdolności do wykonania pracy przez MW oznaczonymi przy użyciu wahadła balistycznego oraz bloku ołowianego. W rezultacie przeprowadzonych badań oraz analizy wyników wyznaczono współczynnik α-Pb, który służy do przeliczania wartości zdolności do wykonania pracy przez MW oznaczonej na wahadle balistycznym na odpowiadające jej wartości wydęcia bloku ołowianego. Główny Instytut Górnictwa jest jedyną Jednostką Notyfikowaną Unii Europejskiej w zakresie Dyrektywy 2014/28/UE, która posiada stanowisko do wytapiania bloków ołowianych oraz aparaturę i środki do oznaczania zdolności do wykonania pracy przez MW w blokach ołowianych – metoda ta została bowiem zaniechana w innych jednostkach badawczych na rzecz badania z użyciem wahadła balistycznego i/lub testu podwodnego.
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The article presents research on the relationship between mining and used resources on the example of Gliśno gravel pit. As regards to resources, the following issues were analyzed: employees’ working time, time of running machines, fuel consumption and electricity consumption. The aim of the publication is to examine the dependencies that exist between the analyzed variables. KPI’s (Key Performance Indicators) were calculated for individual resources. The analysis presented in the publication contains data from 2008-2014.
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The major aim of the research is to analyse the type and complexity of emotions which adolescent musicians experience before giving a solo music performance. Another aim is to explore the function of these emotions for performance quality. Just before a school concert, students filled out The UWIST Mood Adjective Checklist (UMACL). Right after the performance, both the performing students and competent referees used The Performance Evaluation Scale. The results show that musicians’ pre -performance emotional state is dominated by ambivalent emotions of hope and sadness, as well as joy and anxiety. As a result of a cluster analysis, six clusters were obtained which defined emotional states before the performance: high music performance anxiety, moderate music performance anxiety, calm, mixed emotions, joy with background fatigue, and excitement. The findings show the functional significance of positive emotions and mixed emotions for performance quality.
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Learned helplessness is often studied as a consequence of repetitive failure in a performance domain and is usually associated with the experience of uncontrollability over future outcomes. The premise of this review article is first to establish initial support towards the notion of learned helplessness seen in the context of sports performance. Furthermore, the role of performance anxiety and maladaptive perfectionism will be introduced to strengthen the idea that thinking traits impact motor performance especially when these traits moderate the effects of consecutive failure experience. Finally the paper will focus on a typical profile of an athlete who would be susceptible to choking under pressure as an outcome of perceived uncontrollability and performance anxiety. Burnout and potential interventions will be discussed later.
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Performance measurement system in supply chain management (SCM) has been receiving increasing attention by business organizations as a way to evaluate efficiency in supply chain activities. Assessing the performance of supply chain uncovers the gap between planning and actual performance as to trace the potential problems thus ascertain necessary areas for improvement. This research aims to investigate the application of performance measurement system in SCM as well as exploring its relationship with organization’s performance among Malaysian manufacturing firms. By utilizing the questionnaire method, respondents involved were requested to indicate the extent to which they use a number of 24 selected performance measures that are related to SCM. The results show that the majority of the observed manufacturing firms utilize specific performance measurement tools in evaluating the supply chain performance. The current performance measurement techniques, the Balanced Score Card is adopted by around a quarter of the total responding firms followed by Supply Chain Operations References Model – SCOR, which attracts total users of only a fifth of the total respondents. In particular, performance measures under customer service category recorded the highest number of usage followed by cost-based performance measures and operations management. The results of this investigation also unveil few major points that are important to be highlighted. Firstly, the obtained outcomes of this study bring to light the significant relationships between the utilization of supply chain performance measures under customer service, operations management and organizational performance. In addition, this study discovered a significant correlation between the size of the organization and the extent of use of supply chain performance measures and how these two variables positively correlated. Lastly, the findings also suggested that the performance measures for SCM has been playing a crucial role in enhancing the performance of the organizations and is increasingly operated as the firms grow in size. Based on the brief highlighted points listed above, it is not an exaggeration to say that this research contributes new information to the body of knowledge in performance measurement system in SCM and its associations with organizational performance.
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This article reports the effects of CuO/water based coolant on specific fuel consumption and exhaust emissions of four stroke single cylinder diesel engine. The CuO nanoparticles of 27 nm were used to prepare the nanofluid-based engine coolant. Three different volume concentrations (i.e 0.05%, 0.1%, and 0.2%) of CuO/water nanofluids were prepared by using two-step method. The purpose of this study is to investigate the exhaust emissions (NOx), exhaust gas temperature and specific fuel consumption under different load conditions with CuO/water nanofluid. After a series of experiments, it was observed that the CuO/water nanofluids, even at low volume concentrations, have a significant influence on exhaust emissions. The experimental results revealed that, at full load condition, the specific fuel consumption was reduced by 8.6%, 15.1% and 21.1% for the addition of 0.05%, 0.1% and 0.2% CuO nanoparticles with water, respectively. Also, the emission tests were concluded that 881 ppm, 853 ppm and 833 ppm of NOx emissions were observed at high load with 0.05%, 0.1% and 0.2% volume concentrations of CuO/water nanofluids, respectively.
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In multi-axis motion control systems, the tracking errors of single axis load and the contour errors caused by the mismatch of dynamic characteristics between the moving axes will affect the accuracy of the motion control system. To solve this issue, a biaxial motion control strategy based on double-iterative learning and cross-coupling control is proposed. The proposed control method improves the accuracy of the motion control system by improving individual axis tracking performance and contour tracking performance. On this basis, a rapid control prototype (RCP) is designed, and the experiment is verified by the hardware and software platforms, LabVIEW and Compact RIO. The whole design shows enhancement in the precision of the motion control of the multiaxis system. The performance in individual axis tracking and contour tracking is greatly improved.
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This paper presents a new test method able to infer - in periods of less than 7 seconds - the refrigeration capacity of a compressor used in thermal machines, which represents a time reduction of approximately 99.95% related to the standardized traditional methods. The method was developed aiming at its application on compressor manufacture lines and on 100% of the units produced. Artificial neural networks (ANNs) were used to establish a model able to infer the refrigeration capacity based on the data collected directly on the production line. The proposed method does not make use of refrigeration systems and also does not require using the compressor oil.
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A suitable use of software packages for optimization problems can give the possibility to formulate design problems of robotic mechanical systems by taking into account the several aspects and behaviours for optimum solutions both in design and operation. However, an important issue that can be even critical to obtain practical solutions can be recognized in a proper identification and formulation of criteria for optimability purposes and numerical convergence feasibility. In this paper, we have reported experiences that have been developed at LARM in Cassino by referring to the abovementioned issues of determining a design procedure for manipulators both of serial and parallel architectures. The optimality criteria are focused on the well-recognized main aspects of workspace, singularity, and sti#27;ness. Computational aspects are discussed to ensure numerical convergence to solutions that can be also of practical applications. In particular, optimality criteria and computational aspects have been elaborated by taking into account the peculiarity and constraint of each other. The general concepts and formulations are illustrated by referring to specific numerical examples with satisfactory results.
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The joined wing concept is an unconventional airplane configuration, known since the mid-twenties of the last century. It has several possible advantages, like reduction of the induced drag and weight due to the closed wing concept. The inverted joined wing variant is its rarely considered version, with the front wing being situated above the aft wing. The following paper presents a performance prediction of the recently optimized configuration of this airplane. Flight characteristics obtained numerically were compared with the performance of two classical configuration airplanes of similar category. Their computational fluid dynamics (CFD) models were created basing on available documentation, photographs and some inverse engineering methods. The analysis included simulations performed for a scale of 3-meter wingspan inverted joined wing demonstrator and also for real-scale manned airplanes. Therefore, the results of CFD calculations allowed us to assess the competitiveness of the presented concept, as compared to the most technologically advanced airplanes designed and manufactured to date. At the end of the paper, the areas where the inverted joined wing is better than conventional airplane were predicted and new research possibilities were described.
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This article describes queueing systems and queueing networks which are successfully used for performance analysis of different systems such as computer, communications, transportation networks and manufacturing. It incorporates classical Markovian systems with exponential service times and a Poisson arrival process, and queueing systems with individual service. Oscillating queueing systems and queueing systems with Cox and Weibull service time distribution as examples of non-Markovian systems are studied. Jackson's, Kelly's and BCMP networks are also briefly characterized. The model of Fork-Join systems applied to parallel processing analysis and the FES approximation making possible of Fork-Join analysis is also presented. Various types of blocking representing the systems with limited resources are briefly described. In addition, examples of queueing theory applications are given. The application of closed BCMP networks in the health care area and performance evaluation of the information system is presented. In recent years the application of queueing systems and queueing networks to modelling of human performance arouses researchers' interest. Hence, in this paper an architecture called the Queueing Network-Model Human Processor is presented.
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The main objective of this study was to analyse the psychometric properties of the Polish adaptation of the Kenny Music Performance Anxiety Inventory – Revised (K -MPAI -R, Kenny, 2009) modified as the Kenny Performance Anxiety Inventory (K -PAI) for a general population of individuals with experience in public performance in fields other than music. Another aim was to test the factor structure of K -PAI on a Polish sample. We analysed the relationship between the scores on K -PAI and general anxiety, depression, attentional control, the scores on the Behavioural Inhibition Scale (BIS) and the Behavioural Activation Scale (BAS) and reward susceptibility. Participants (N = 586) completed the questionnaires in a wider online study. The scores on K -PAI revealed a moderate to strong positive association with different measures of anxiety, trait -anxiety in particular, and negative associations with attentional control and susceptibility to reward. K -PAI scores were strongly associated with depression, but displayed no relationship with the BAS or any of its sub -dimensions. These results generally replicated those obtained on the K -MPAI -R with Australian and Peruvian musicians, indicating the cross -cultural validity of the K -MPAI -R and K -PAI. It is suggested that performance anxiety develops on the basis of the biological predispositions and early negative experiences in performance contexts.
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The paper presents the theory of constraints (TOC) as a method used to improve results in a complex, multiplants organization. In the article the assumptions of this method has been presented as well as iterative approach concerning how to launch it in practice. Main indicators for organizational effectiveness assessment have also been presented. The maximization of production assets utilization is a key issue for competitive organization in the changing market conditions. An appropriate usage of the theory of constraints enables efficient allocation of financial assets among particular plants within a capital group. An application of a method has been presented based on throughput analyses and its influence to improve financial results of one plant organization and synergy effect in multiplants organization. The theory of constraints can be used in almost every kind of business sectors, among them are metal and foundry industries. It allows to be implemented in production organizations as well as in any other company’s profiles. Everywhere the constraint has been defined there is a chance to achieve an improvement following the presented method. The examples have been taken from the casting plants which use continuous and mold casting technologies. The examples show that TOC approach can be successfully employed as the improvement tool of foundries’ performances.
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The material presents a real problem inherent in the management of computer systems, namely that of finding the appropriate system settings and thus being able to achieve the expected perfor- mance. The material also presents a prototype which aims to adapt the system in such a way as to achieve the objective, defined as the application efficiency. The prototype uses a resource-oriented mechanism that is built into the OS Workload Manager and is focused on a proposed goal-oriented subsystem based on fuzzy logic, managing resources to make the best use of them, and pursuing translation to the use of system resources, including nondeterministic technology-related factors such as duration of allocation and release of the resources, sharing the resources with the uncapped mode, and the errors of performance measurement.
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An accurate use of the ability to steer computer efficiency is essential from the database point of view. Effective resource allocation is dependent on the performance indicators gathered from running systems. There must be an appropriate balance between accurate measurements, performance indicators and speed of the reallocation algorithms of the computing resources. The extended measurement of efficiency which the authors propose for applications is: the average number of queries within a time unit for particular groups of users. This paper presents an analysis of using the Workload Manager utility in the AIX 5L operating system to improve the efficiency of applications in the MySQL database environment, and an analysis of methods which allows the use of Workload Manager for steering efficiency dynamically.
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This paper investigates attachment themes in the life history narratives of professional orchestral musicians and their relationship with music performance anxiety (MPA). Narrative accounts derived from open -ended in -depth interviews of ten professional musicians were analysed from an attachment perspective using content and thematic analysis. We hypothesized that the performance setting re -triggers unprocessed feelings related to early attachment experiences, especially when traumatic, and that defensive manoeuvres against their re -emergence into consciousness are activated. The interviews identified early relational trauma as a relevant etiological factor in the MPA -symptomatic of the musicians studied. A case is made for the addition of an attachment -informed life -course model rather than a purely symptomatic approach to understanding and treating severe MPA and other intra -personal psychodynamics of performing musicians.
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An original fuzzy team control model is presented in this article. The model is based on a non-traditional combination of classical and contemporary achievements of management and mathematical theories of fuzzy logic and fuzzy sets. In methodological terms, the article also offers a set of tools for measuring and evaluating both team performance and the effectiveness of the team control system in the organization. Fuzzy tools and techniques for decision-making, studying of hidden effects and joint influences, and quantification of evaluations are employed in this set of tools. The suggested fuzzy model contributes to overcoming theoretical deficits on the issues of team control, and the methodology of team control fills a gap in the toolkit of team management. The results from verification of the fuzzy team control model at a small-sized Bulgarian enterprise are also discussed in this article. They indicate that it is possible to develop a fuzzy model for team control, increasing the effectiveness of the team control system in the enterprise.
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In the article problems related to human labor and factors affecting the increasing use of industrial robots are discussed. Since human factors affect the production processes stability, robots are preferred to apply. The application of robots is characterized by higher performance and reliability comparing to human labor. The problem is how to determine the real difference in work efficiency between human operator and robot. The aim of the study is to develop a method that allows clearly definition of productivity growth associated with the replacement of human labor by industrial robots. Another aim of the paper is how to model robotized and manual operated workstation in a computer simulation software. Analysis of the productivity and reliability of the hydraulic press workstation operated by the human operator or an industrial robot, are presented. Simulation models have been developed taking into account the availability and reliability of the machine, operator and robot. We apply OEE (Overall Equipment Effectiveness) indicator to present how availability and reliability parameters influence over performance of the workstation, in the longer time. Simplified financial analysis is presented considering different labor costs in EU countries.
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The article shows the methodology and calculation procedures based on Lagrange polynomial interpolation which were used to determine standard performance characteristics of the Polish production engine, type ANDORIA 4CTi90-1BE6. They allow to simplify the experimental research by maintaining a minimum number of measurement points and estimating the remaining data in an analytical way. The methods presented are convenient when it comes to the practical side because they eliminate the need for exploration of mathematical equations describing the various curves, which can be cumbersome and time consuming in the case of nonautomated accounts. The results of analysis were applied to actual experimental results, indicating sufficient accuracy of the resulting approximations. As a result, procedures may be used in bench testing of a similar profile, especially with repeated cycles of the experiment, such as optimization of operating parameters of combustion engines.
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Introduction: The history of using performance-enhancing substances (PES) is long and it goes back to ancient times. At present, PES are employed at all levels of sport competition, starting from Olympic level contestants to individuals recreationally involved in various sports disciplines. Purpose: The objective of the study was examining the views on doping in sports in a group of physicians, together with evaluating the frequency of their contacts with this phenomenon, in their professional activities. Methods: The investigation was carried out using a validated questionnaire developed by the authors. Questionnaire included 34 questions divided into 6 sections. In total, 257 individuals participated in the study. The percentage of answers was 75.81%. Results: Among the responders, 96.50% believed that using PES by sports competitors represented unethical behavior. 42% participants declared that they met doping problem during their professional career. Almost one-third of the physicians (28.79%) declared that during their work, they consulted patient suffering from adverse side eff ects resulting from using PES. Conclusions: In Poland, physicians regard using PES as unethical behavior. They believe that a health care system professional should participate in counteracting doping in sports. Physicians — regardless of their specialty — are also exposed to PES-related problems in their professional work. In view of the above facts and the consistently increasing popularity of PES, extending the knowledge in this field among physicians seems to be of importance to allow for their offering better medical services to their patients.
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The new control method for Permanent Magnet Synchronous Motor (PMSM) and Brushless DC Motor (BLDCM) is presented. Balance of power in three-phase permanent magnet synchronous motor is based on conservation of energy law. Space vector theory determined by instantaneous value of phase quantities is applied in mathematical analysis. It makes possible to estimate instantaneous values of reactive energy and electromagnetic torque. The presented control method belongs to flux-oriented method; it synchronizes current vector in relation to stator flux vector. New structure of control system as well as block diagram containing all basic elements and operating modes of specific blocks are described. Simulation studies and experimental results for two kinds of motors: PMSM and BLDCM were performed based on the dSPACE development DS1103 system.
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A brief review of the existing autonomous underwater vehicles, their types, design, movement abilities and missions is presented. It is shown, the shape optimization design and enhancement of their efficiency is the main problem for further development of multipurpose glider technologies. A comparative study of aerodynamic performance of three different shape designs (the airfoil NACA0022 based (I), flattened ellipsoidal (II) and cigar-type (III) bodies of the same volumes) has been carried out. Geometrical modelling, meshing and computational fluid dynamics (CFD) simulations have been carried out with AnSys15.0. The pathlines and wall shear stress distributions have been computed to understand the advantages and disadvantages of each shape. The lift and drag coefficients, aerodynamic quality, power index and pitching moment have been computed. The higher efficiency of the shape I/shape II at higher/lower angles of attack (> 20o and < 20o) has been found. The shape III develops high speeds at the same angles of attack and has higher manoeuvrability at relatively low aerodynamic quality. The comparative analysis of the flow capabilities of studied autonomous undersea vehicles proposes some design improvement for increasing their energy efficiency and flow stability.
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