Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 29

Liczba wyników na stronie
first rewind previous Strona / 2 next fast forward last
Wyniki wyszukiwania
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 2 next fast forward last
EN
The most common types of damage in distribution networks with a voltage of 6-35 kV have been analyzed. It is shown that the majority of them are single-phase circuits, which can cause overvoltages at the point of damage and negatively affect electrical equipment, which can lead to a decrease in economic indicators. The methods of increasing the reliability of distribution networks with a voltage of 6-35 kV have been analyzed. The main attention is focused on the method of increasing reliability due to grounding of the neutral through an arc reactor, the main advantage of which in operation is the continuation of single-phase ground fault operation without disconnection of consumers. A simulation model of the distribution network in single-phase ground fault mode was developed and its main parameters were calculated. The DiGSILENT PowerFactory software complex is used as a simulation environment. A concrete example of parameter calculation when using the proposed simulation model in the DiGSILENT PowerFactory program, which contains 5 overhead and 5 cable power transmission lines with a voltage of 35 kV with a length of 10 to 100 kilometers. The use of this model will make it possible to study transient processes in the mode of single-phase grounding, to prevent emergency situations in distribution networks. The goal of the work ist development of the simulation model of the distribution network in the mode of single-phase circuit to land and the calculation of its basic parameters.
EN
The rapid and voluminous development of renewable generation, and its stochastic nature, creates problems in terms of maintaining frequency and balance in the power system. In this work, demand response management and the use of the concept of demand response are discussed in detail. The potential of using prosumers to maintain the power balance in the power system is considered. The analysis of prosumers was carried out on the basis of a study of load schedules of typical consumers with software that forms schedules taking into account socio-demographic characteristics.
EN
This work is a Copper oxide (CuO) thin films were effectively produced using cold spray technique. The process take place in an inert gas (helium) without using catalyst. Nano CuO was deposited on a glass slide, using helium as carrier gas heated to 100, 200, 300, and 400oC, respectively on heated glass substrates at 300°C. The effect of structural and electrical properties was examined at each temperature for each film. AFM images show that the CuO thin film have different diameters ranging from 80 to 600 nm, and low surface roughness about 20.9 nm. The measured value of copper oxide resistivity was found to be decrease very much with the increasing temperature. All the result showed that copper oxide is suitable material for photovoltaic applications. This research is part of a larger work for the solar cells industry. Therefore, the aim of this research is to study the electrical properties of solar cells in the primary stages of manufacturing from available materials at low costs.
EN
Increasing requirements in the field of monitoring the impact of machines contributes to the analysis of production processes in order to verify their environmental loads. The research carried out in this area is aimed at identifying the negative impact of the tested object to be able to introduce changes in the consumption of raw materials and energy while limiting the negative impact on the environment. The article will present the results of the life cycle assessment (LCA) of the process of mass, thermo-shrinkable packaging of beverage bags depending on the change in the way the packaging machine is powered. In addition, as part of the analysis, it was indicated which stage of the process has the biggest negative impact on the environment. LCA results are presented at the stage of endpoint characterization.
EN
The article presents a comparison of the results of simulation by a photovoltaic installation with bifacial modules. The analyzed 20 kWp PV installation was located in the Kuyavian-Pomeranian Voivodeship. The article compares how the energy production of installations with bifacial modules changes depending on the angle of inclination, the distance between the rows of modules and the orientation. The results obtained in the study indicate that albedo is an important, but not the only parameter to be considered when designing a farm with bifacial modules.
EN
Large PV installations are being built increasingly often in areas close to airports in Poland and around the world. These are not only roof installations but also large PV farms, allowing not only the supply of the energy for the airport itself but also the ability to sell the excess energy produced. The applied PV installations may cause in some cases negative impact in the form of e.g., electromagnetic fields and light reflections which may limit the visibility of pilots and air traffic controllers. The article presents an overview of various negative impacts of PV farms on the workings of an airport and the main factors influencing the occurrence of certain threats have been diagnosed. An assessment of the usefulness of the tool and method for simulation and the reduction of possible negative impacts is also presented.
EN
Nowadays Life Cycle Assessment is the most popular tool that can be used to see environmental load of a machine, a product or a process. LCA defines the impact throughout the life of a product, from the extraction or production of raw material from natural resources, through production, use and final disposal. This method focuses on the assessment of the impact of the tested object on the area of the ecosystem, human health and the resources use. LCA is a very helpful tool in the environmental assessment that is required and results from the current policy of the European Union, which requires the member states to minimize the harmful impact on the environment of every aspect of human life. The publication discusses the LCA life cycle assessment method as one of the methods allowing to estimate the environmental impact of a technological process or some product. The article shows also the history of LCA, the individual stages, advantages and disadvantage this method. This paper it is also an introduction to carry out LCA analysis on the example of a process with the use of the shrink film.
EN
Nowadays, more and more solar farms are being created in Poland. This is due to the development of PV technology, the appearance of more efficient systems on the market, but also the need for Poland to achieve a 50% share of energy production from zero-emission sources. In designing PV farms, an important issue is the selection of the right angle, but also the distance between individual rows of panels. The article shows the work analysis of the 1 MW PV farm consisting of 2000 units of 500 Wp panels with dimensions of 2220 mm x 1108 mm x 40 mm and a weight of 28.60 kg and 8 inverters SUN2000-105KTL-H1. The panels are arranged in 10 rows in two directions: south and south-west. The analysis was performed for the angles of 10°, 20°, 25° and 30°. The investigation was carried out in order to evaluate the effect of changing the angle of the panels and the distance between the rows on the PV farm efficiency.
EN
In the paper the D3 discipline of the G8D method has been presented. In the presented procedure all decisions are made regarding the introduction of interim corrective actions - ICA. The algorithm of conduct for the discipline and the quality management tools that the discipline uses have been also presented. It has been also discusses how to proceed for the D3 discipline in determining temporary corrective actions for the NOK detail with the preceding actions in the D2 discipline.
EN
In this paper, the authors focused on the analysis and evaluation of factors affecting the level of occupational risk in "small" enterprises, with a particular emphasis on psychophysical factors in the manufacturing sector. The study was conducted using a self-administered questionnaire. The results were verified using the strucla interview method with elements of observation. The purpose of the paper was to draw attention to – often overlooked in the assessment of occupational risks by employers – psychophysical hazards with particular emphasis on psychosocial hazards. Respondents – employees of enterprises with a particular focus on the manufacturing sector – point to psycho-physical hazards as those that, right after hazardous (accident) hazards, significantly affect the level of occupational risk. However, the assessment of factors determining the level of occupational risk changes with the age of respondents. Older workers, more often than younger ones, perceive the factors that affect the level of occupational risk. Their experience and ability to reliably identify risks can be very useful in creating awareness of safe behavior among the youngest workers, who are most vulnerable to occupational accidents. The article also presents analyses and assessments of the symptoms of occupational stress, which is one of the factors shaping psycho-physical risk that is so often underestimated by many workers and employers.
EN
The article presents a comparison of results from a simulation of the energy production by a photovoltaic installation with a tracking system and a stationary PV farm in the PVSyst program. The analyzed 1 MW PV installations were located in the Kuyavian-Pomeranian Voivodeship in Poland. Energy production results obtained from the installation with a tracking system were compared with a stationary farm with panels placed at an angle of 20° and an azimuth 0°. The paper also presents the types of tracking systems and discusses the advantages of this solution and its risks compared to traditional panel mounting. The results obtained in the study indicated that the use of a tracking system increased the annual energy production compared to a stationary farm.
EN
A composite pressure vessel is an important structure in different applications including pipes, pipes under pressure and closed system pipes under high pressure and temperature such as gas pipelines and aircraft structures, because of the characteristics of polymer - a composite used as an alternative to heavy materials such as metal in the various applications, including the construction industry. The current work focuses on the study of strength phase orientation and their properties on the burst pressure strength and other parameters, which are very important in the design and manufacture of these vessels such as the selection of type of strength phase nylon 6, 6 and philosophy of mixing of the type of fiber with matrix material (epoxy). The work also includes the study of the effect of two layer angle ply (0, 90), (55, -55), (75, -75) and implements different material testing to evaluate the toughness and stiffness of these vessels and compare the experimental result with the theoretical result. A filament winding apparatus was designed and executed to manufacture different types of subjects according to these angle of ply nylon fiber. The mechanical tests (tensile test, drop test, pipe stiffness test, hydrostatic pressure test) were used to test the vessel. The results shown that the ply orientation (75, -75) has high (tensile strength, toughness, stiffness, impact and burst pressure) when compared with the results from other ply orientations. This shows that [75, -75] ply orientation is the optimal angle for the vessel. Tensile tests show that (75, -75) ply orientation samples have higher properties in two directions, longitudinal and transverse, when compared with other angles.
EN
Eco-efficiency is a new concept of environmental analysis seeking to improve products, processes and manufacturing materials. The eco-efficiency analysis gives the opportunity to find the most effective solution with the lowest environmental burden in the bottle forming process. For this purpose, the LCA (Life Cycle Assessment) technique of environmental management was used to evaluate selected stages of the bottle forming process. The analysis was carried out using the Eco Indicator 99 method using the SimaPro software.
14
Content available Impact world+ a new method for life cycle assessment
EN
With the IMPACT WORLD+ life cycle impact assessment methodology, the impact of a facility's life can be analysed. All midpoint scores are expressed in units of substance and refer to twenty-one damage categories. The distinctive feature of this method is its regionalized nature covering the whole world, which distinguishes it from other methods that deal with selected geographical regions. The IMPACT WOLRD+ method, like other methods, emphasises which factors have a high impact on human health and which factors have a negligible share. The new method also introduced new indicators that were not included in other methods.
15
EN
Recently, there has been a large development of photovoltaics in Poland and in the world. This work shows how the energy profit of a high-power photovoltaic farm changes with the change of the angle of inclination of the panels on the example of a PV power plant project in the Siemiatycze districtin the Podlaskie Voivodeship. In order to verify the energy gain, measurements were made in the PVSyst program for panels with a power of 600 Wp, the spacing of 10 m or 6 m for angles from 20° to 25°. Based on the analysis, the results were obtained, which indicate that with an increase in the angle of inclination in the studied range of angles, the annual production of energy by power plants increases. The difference between the production for the angle of 20° and the angle of 25° is 1010 MWh, which means profits higher by almost 1% per year. on the basis of the selected row spacing and angle, an analysis was carried out, which shows that the average amount of energy generated in a 140 MW installation will be approximately 149 246 MWh. The article also contains an analysis of losses which are generated during the work of PV panels.
EN
In the paper an economic, ecological and energy analysis of a home photovoltaic on grid installation was presented. The increase in ecological awareness of the Polish society contributes to the continuous growth of interest in green energy. However, many people haven’t been aware of the ecological, economic and energy benefits of photovoltaic installations yet, so the following analysis is made. The analysis concerns a photovoltaic installation with a capacity of 3.96 kWp located in Ościęciny near Włocławek. The photovoltaic installation consists of 11 monocrystalline panels with a power of 360 Wp, a 4 KTLM Sofar Solar inverter and other necessary components. The first part presents basic issues related to photovoltaic installations. Parameters related to the proper functioning of the photovoltaic installation were replaced. The analysis of the literature will help to understand the essence of the proper functioning of the photovoltaic installation. In the practical part, an analysis of a selected home photovoltaic installation was carried out. Based on the available data, it has been calculated that the installation will have a payback period of over 9 years. The photovoltaic installation will produce approximately 3 582.61 kWh of electricity and will contribute to the reduction of 70 tons of carbon dioxide during the entire operation.
EN
The paper focuses on the analysis of the impact of technical, organizational and human factors on accident rate in small-sized enterprises. The research was carried out using the authors’ questionnaire. The results were verified using the method of direct interview with elements of observation. The results were compared with the trends prevailing in enterprises of EU countries. The respondents, i.e. production company workers, indicate technical factors as those which most significantly affect the occurrence of accidents at work. However, the assessment of the factors changes with the age of the respondents. Older workers, more often than younger employees, indicate the ones related to man or work organization as the most important factors affecting accidents at work and, consequently, the level of occupational safety. The presented results are a part of a larger whole project the authors of this paper are working on.
18
EN
In the present paper, the scope of the process line maintenance in the production plant has been presented. The issues associated with the basic functions and characteristics of the services dealing with this problem, which is crucial for the production plant, have been discussed. Modern CMMS (Computerized Maintenance Management Systems) have been discussed, while indicating their specific ad-vantages, among others, the possibility of keeping records of machinery and equipment, maintenance schedules and various types of alarms, which may disrupt or suspend the operation of production facilities, so that these systems ensure the safety of fault-free operation of machinery and equipment.
EN
In recent years, there has been an increase in the consumption of disposable packaging, which has led to overloading landfills. These problems have become widely noticeable and dominant in a wide range of packaging issues in terms of environmental protection. The development of knowledge in the field of environmental protection, which has taken place in recent years, has shown that the impact of packaging should be considered throughout its life cycle, taking into account many factors that constitute environmental burdens and threats. Many companies operating in the world markets, using the standardized Life Cycle Assessment (LCA) method, conduct tests in terms of technical and material solutions with the lowest environmental impact. Therefore, this publication was to conduct environmental analysis of the life cycle of disposable food packaging based on the method of LCA. The subject of the research were bottles, caps and labels made mainly of polymeric materials: polyethylene terephthalate, polypropylene and LDPE. Eco-indicator 99 was used as the calculation procedure. The impact of the analysis objects on human health, ecosystem quality and resources was assessed. Among the examined objects, the highest level of negative influence on the environment was characteristic for the life cycle of a polyethylene terephthalate (PET) bottle. The use of recycling processes reduce the environmental impact by about 25%.
EN
The G8D method is one of the methods used in quality management using quality management tools and designed to solve problems occurring in production processes. The method consists of 8 disciplines and ensures the required quality of both production processes and finished products. It may also be applied to the optimization of production processes, while ensuring their safety. In the article, the authors presented the method of using the D4 discipline algorithm of the G8D method allowing to detect the root cause of the problem in the process and to indicate the so-called escape point. The authors presented the course of action for discipline D4 undertaken when the root cause of the problem is to be analysed. The procedure is presented on an exemplary process of the projection welding of a nut.
first rewind previous Strona / 2 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.