scholarly journals Thermal Behaviour of a Solar Dish Collector with Flat Mirrors Using CFD Analysis

2020 ◽  
Vol 38 (4) ◽  
pp. 767-774
Author(s):  
Mario A. Cucumo ◽  
Vittorio Ferraro ◽  
Dimitrios Kaliakatsos ◽  
Francesco Nicoletti ◽  
Davide Condò
Keyword(s):  
Optical Model ◽  
Fluid Dynamic ◽  
Point Of View ◽  
Hot Water ◽  
Production Plant ◽  
Energy Point ◽  
System A ◽  
Imaging Camera ◽  
Thermal Generator ◽  
The University

In this work a Solar Thermal Generator is analysed from an energy point of view. It is a dish collector that is part of a concentrating solar grid system. The analysed plant is used for the generation of low enthalpy thermal energy as an integration to the hot water production plant for some student residences of the University of Calabria (Italy). A thermal model is developed that simulates the behaviour of the plant with the aim of analysing its performance and optimizing the design of its fundamental parts from an energy point of view. The optical model of the solar collector is carried out for a particular external condition. The emissive characteristics of the absorber is determined with the use of a thermal imaging camera. To identify the main parameters that affect the functioning and the thermal balance of the capturing system, a thermo-fluid dynamic analysis is performed. The results show which are the main causes of loss. It is possible to understand the weight of each factor in the energy balance.

scholarly journals Modification of the Role of a Teacher Under the Conditions of Distance Learning

2021 ◽  
Vol 16 (21) ◽  
pp. 219
Author(s):  
Ekaterina Viktorovna Otts ◽  
Elena Pavlovna Panova ◽  
Yuliya Vladimirovna Lobanova ◽  
Natalya Victorovna Bocharnikova ◽  
Valentina Michailovna Panfilova ◽  
...  
Keyword(s):  
Higher Education ◽  
Distance Learning ◽  
Educational Process ◽  
Point Of View ◽  
System A ◽  
Teachers And Students ◽  
Scientific Principles ◽  
The University ◽  
The Impact

The article examines the features of the transformation of the role of a teacher in higher education in connection with the digitalization of education in the period before the pandemic, and during the transition of the university to a forced remote mode under the conditions of the pandemic. The assessment of the effectiveness of distance learning from the point of view of students and teachers is given. The purpose of the article is to determine expectations, the degree and nature of the influence of the teacher's personality on the effectiveness of educational process in general and distance learning in particular. Researching the effectiveness of higher education in the digital age and assessing the impact on teacher effectiveness involves the use of a number of scientific principles and research methods, theoretical and empirical. To achieve the goal, the scientific works of leading foreign and Russian scientists on the problems of digitalization of education, dehumanization of education, transformation of the role of the teacher have been analyzed, and our own research has been carried out on the basis of the Moscow Polytechnic University in the form of a survey. An assessment of the emotional consequences of isolation is given. The analysis of the effectiveness of distance learning, from the point of view of higher education teachers and students has been carried out. The expectations of students and the change in the role of a teacher of higher education as a result of expansion of functional responsibilities under the circumstances of distance learning are described. Long before the coronavirus pandemic, digitalization had been a trend in the education system. A year of distance learning has revolutionized higher education. The role of a teacher in higher education has been transformed with a significant expansion of functions and a rapid increase in the level of competencies.

Dynamic Modeling, Simulation and Exergy Analysis of an Innovative Hydronic Heating System

2013 ◽  
Author(s):  
R. Sangi ◽  
R. Streblow ◽  
Dirk Müller
Keyword(s):  
Modeling And Simulation ◽  
Dynamic Modeling ◽  
Heating System ◽  
Point Of View ◽  
Hot Water ◽  
Domain Modeling ◽  
Demand And Supply ◽  
System A ◽  
Energy Chain ◽  
Central Circulation

In this study, dynamic modeling and simulation of a decentralized hydronic heating system has been performed. The simulated space heating system is a model of an innovative heating system of an apartment with a boiler that supplies heat for eight radiators which are served by distribution pipes. Eight small pumps, located at the outlet of the radiators instead of a central circulation pump, work according to demand, and supply each radiator with hot water only when required. A PID controller regulates the rotational speed of the pumps and consequently the power of the radiators to maintain the room temperature at the set point. To evaluate the performance of such a heating system, a model of the entire energy chain from generation to distribution is needed. Therefore, in this work, detailed sub-models for the hydraulic system have been developed and coupled with the model of a building to make a general model for simulating the performance of the whole system. The analysis has been carried out by simulation of the system using the object-oriented programing language Modelica. Dymola, which is a multi-domain modeling and simulation tool, has been used as simulation environment. The Modelica Standard Library 3.2 and the Modelica libraries for building simulation such as BaseLib, Database, Building and HVAC components libraries have been applied to simulate the hydraulic and thermal behavior of the system. In the next step, the system has been analyzed form exergy point of view and the simulation results from the dynamic model have been presented in an exergetic framework.

High-resolution electron microscopy of Cu2O surfaces

1986 ◽  
Vol 44 ◽  
pp. 396-397
Author(s):  
V. Castano ◽  
W. Krakow
Keyword(s):  
High Resolution ◽  
Natural Extension ◽  
High Resolution Electron Microscopy ◽  
Point Of View ◽  
Initial Oxidation ◽  
System A ◽  
Resolution Electron ◽  
Surface Reconstructions ◽  
Atomic Surface ◽  
Au Thin Films

In non-UHV microscope environments atomic surface structure has been observed for flat-on for various orientations of Au thin films and edge-on for columns of atoms in small particles. The problem of oxidation of surfaces has only recently been reported from the point of view of high resolution microscopy revealing surface reconstructions for the Ag2O system. A natural extension of these initial oxidation studies is to explore other materials areas which are technologically more significant such as that of Cu2O, which will now be described.

Environmental cell studies of deformation and fracture

1990 ◽  
Vol 48 (4) ◽  
pp. 516-517
Author(s):  
H. K. Birnbaum ◽  
I. M. Robertson
Keyword(s):  
National Laboratory ◽  
Argonne National Laboratory ◽  
Damage Threshold ◽  
Chromatic Aberration ◽  
Good Choice ◽  
Point Of View ◽  
Deformation And Fracture ◽  
Environmental Cell ◽  
Gas Molecules ◽  
The University

Studies of the effects of hydrogen environments on the deformation and fracture of fcc, bcc and hep metals and alloys have been carried out in a TEM environmental cell. The initial experiments were performed in the environmental cell of the HVEM facility at Argonne National Laboratory. More recently, a dedicated environmental cell facility has been constructed at the University of Illinois using a JEOL 4000EX and has been used for these studies. In the present paper we will describe the general design features of the JEOL environmental cell and some of the observations we have made on hydrogen effects on deformation and fracture.The JEOL environmental cell is designed to operate at 400 keV and below; in part because of the available accelerating voltage of the microscope and in part because the damage threshold of most materials is below 400 keV. The gas pressure at which chromatic aberration due to electron scattering from the gas molecules becomes excessive does not increase rapidly with with accelerating voltage making 400 keV a good choice from that point of view as well. A series of apertures were placed above and below the cell to control the pressures in various parts of the column.

Introduction of a quality management system compliant with DIN EN ISO 9001:2000 into a university department of nuclear medicine

2001 ◽  
Vol 40 (06) ◽  
pp. 228-238 ◽  
Author(s):  
U. Paschen ◽  
S. Kröger ◽  
K. H. Bohuslavizki ◽  
M. Clausen ◽  
V. Jansen-Schmidt
Keyword(s):  
Nuclear Medicine ◽  
Quality Management System ◽  
Iso 9001 ◽  
Total Quality ◽  
System A ◽  
General Rules ◽  
Therapeutic Procedures ◽  
University Department ◽  
Referring Physicians ◽  
The University

SummaryIn 1995, the management of the University Clinic Hamburg-Eppendorf proposed to establish a total quality assurance (QA) system. A revised QA-system has been introduced stepwise in the department of nuclear medicine since 1997, and certification was achieved in accordance with DIN EN ISO 9001:2000 on February 14,2001.The QA-handbook is devided into two parts. The first part contains operational (diagnostic and therapeutic) procedures in so-called standard operating procedures (SOP). They describe the indication of procedures as well as the competences and time necessary in a standardized manner. Up to now, more than 70 SOPs have been written as a collaborative approach between technicians and physicians during daily clinical routine after analysing and discussing the procedures. Thus, the results were more clearly defined processes and more satisfied employees.The second part consists of general rules and directions concerning the security of work and equipment as well as radialion protection tasks, hygiene etc. as it is required by the law. This part was written predominantly by the management of the department of nuclear-medicine and the QA-coordinator. Detailed information for the patients, documentation of the work-flows as well as the medical report was adapted to the QM-system. Although in the introduction phase of a QA-system a vast amount of time is necessary, some months later a surplus for the clinical workday will become available. The well defined relations of competences and procedures will result in a gain of time, a reduction of costs and a help to ensure the legal demands. Last but not least, the QA-system simply helps to build up confidence and acceptance both by the patients and the referring physicians.

A Futures Study on the Quality Of Life from the Point Of View of Iranian Youth

2017 ◽  
Vol 14 (2) ◽  
pp. 1
Author(s):  
Sina Saeedy ◽  
Mojtaba Amiri ◽  
Mohammad Mahdi Zolfagharzadeh ◽  
Mohammad Rahim Eyvazi
Keyword(s):  
Quality Of Life ◽  
Life Satisfaction ◽  
Mixed Model ◽  
Satisfaction With Life ◽  
Point Of View ◽  
Human Society ◽  
Futures Studies ◽  
The Social ◽  
The University

Quality of life and satisfaction with life as tightly interconnected concepts have become of much importance in the urbanism era. No doubt, it is one of the most important goals of every human society to enhance a citizen’s quality of life and to increase their satisfaction with life. However, there are many signs which demonstrate the low level of life satisfaction of Iranian citizens especially among the youth. Thus, considering the temporal concept of life satisfaction, this research aims to make a futures study in this field. Therefore, using a mixed model and employing research methods from futures studies, life satisfaction among the students of the University of Tehran were measured and their views on this subject investigated. Both quantitative and qualitative data were analysed together in order to test the hypotheses and to address the research questions on the youth discontentment with quality of life. Findings showed that the level of life satisfaction among students is relatively low and their image of the future is not positive and not optimistic. These views were elicited and discussed in the social, economic, political, environmental and technological perspectives. Keywords:  futures studies, quality of life, satisfaction with life, youth

Chemical analysis: Information contribution of results

1991 ◽  
Vol 56 (3) ◽  
pp. 505-559 ◽  
Author(s):  
Karel Eckschlager
Keyword(s):  
Analytical Chemistry ◽  
Information Theory ◽  
Set Theory ◽  
Fuzzy Set Theory ◽  
Information Gain ◽  
Analytical Signal ◽  
Point Of View ◽  
System A ◽  
Review Analysis ◽  
Theory Point

In this review, analysis is treated as a process of gaining information on chemical composition, taking place in a stochastic system. A model of this system is outlined, and a survey of measures and methods of information theory is presented to an extent as useful for qualitative or identification, quantitative and trace analysis and multicomponent analysis. It is differentiated between information content of an analytical signal and information gain, or amount of information, obtained by the analysis, and their interrelation is demonstrated. Some notions of analytical chemistry are quantified from the information theory and system theory point of view; it is also demonstrated that the use of fuzzy set theory can be suitable. The review sums up the principal results of the series of 25 papers which have been published in this journal since 1971.

scholarly journals Spirals of Sustainable Academic Motivation, Creativity, and Trust of Higher Education Staff

2021 ◽  
Vol 13 (13) ◽  
pp. 7057
Author(s):  
Martina Blašková ◽  
Dominika Tumová ◽  
Rudolf Blaško ◽  
Justyna Majchrzak-Lepczyk
Keyword(s):  
Higher Education ◽  
Academic Motivation ◽  
Slovak Republic ◽  
Point Of View ◽  
Scientific Management ◽  
Administrative Staff ◽  
Sustainable Systems ◽  
New Concepts ◽  
Future Improvement ◽  
The University

Sustainability has to penetrate more and more into higher education. It should not focus only on traditional elements. It should also enter new, but for future improvement, extremely important areas. Based on this premise, creativity and motivation, when additionally interconnected and supported by trust that is provided and achieved, decide on the progress and sustainability of universities. This connection is gaining importance especially from the point of view of building solid foundations and mechanisms that functionally preserve the potential effects of these elements in the future. For this reason and following the nature, importance, and content of sustainable academic motivation (SAM), the paper introduces two new concepts: sustainable academic creativity (SAC) and sustainable academic trust (SAT). For further original contributions, the paper hypothesizes the existence of mutual—spiral—relations of sustainable academic motivation (SAM), sustainable academic creativity (SAC), and sustainable academic trust (SAT). The empirical section tests the validity of this claim in the universities of two countries: the Slovak Republic and Poland. A survey performed on a sample of n=181 pedagogical, scientific, management, and administrative staff in higher education confirms the existence of these spirals. The results indicate the spiral effect of motivation when connected with creativity and trust and show that it is accented by the crucial principles of sustainability (responsibility, novelty, usefulness, progress, etc.). Therefore, the paper’s conclusion contains the explanations for the potential occurrence of three types of sustainably mutual systems and complexes. These are: (a) individual sustainable systems of SAM, SAC, and SAT; (b) group/sectional sustainable systems of SAM, SAC, and SAT; and (c) the global sustainable complex of SAM, SAC, and SAT in the university.

scholarly journals New Deterministic Mathematical Model for Estimating the Useful Energy Output of a Medium-Sized Solar Domestic Hot Water System

Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2753
Author(s):  
Miroslaw Zukowski ◽  
Walery Jezierski
Keyword(s):  
Thermal Power ◽  
Optimization Procedure ◽  
Climatic Conditions ◽  
Point Of View ◽  
Hot Water ◽  
Energy Output ◽  
Daily Consumption ◽  
Software Environment ◽  
Optical Efficiency ◽  
Domestic Hot Water

According to the authors of this paper, the mathematical point of view allows us to see what sometimes cannot be seen from the designer’s point of view. The aim of this study was to estimate the influence of the most important parameters (volume of heat storage tanks, daily consumption of domestic hot water, optical efficiency, heat loss coefficient, and total area of a solar collector) on the thermal power output of solar domestic hot water (SDHW) system in European climatic conditions. Three deterministic mathematical models of these relationships for Madrid, Budapest, and Helsinki were created. The database for the development of these models was carried out using computer simulations made in the TRNSYS software environment. The SDHW system located at the Bialystok University of Technology (Poland) was the source of the measurement results used to validate the simulation model. The mathematical optimization procedure showed that the maximum annual useful energy output that can be obtained from 1 m2 of gross collector area is 1303 kWh in the case of Madrid, 918.5 kWh for Budapest, and 768 kWh for Helsinki weather conditions.

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