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Ale mamy wyniki w innych katalogach.Wyniki wyszukiwania dla: START-UP
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Software development methodologies and practices in start-ups
PublikacjaSoftware start-ups are aiming to develop cutting-edge software products under highly uncertain conditions, overcoming fast-growing markets under multiple influences. This study aims to identify and analyse the existing scientific literature regarding software development methodologies and practices in software start-ups published between January 2006 and December 2017 using the systematic mapping study. The results identified 37...
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Influence of the low ambient temperature on the start-up process of hydraulic pumps
PublikacjaStarting hydraulic pumps in low ambient temperatures may cause: decreased hydraulic-mechanical efficiency, larger vibration of hydraulic installation, faster wear and more frequent damage to the elements of pumps, change of material properties of elements, increase of pressure drop. As a result of pressure drop in the suction pipe, large underpressure may be experienced, causing incomplete filling of pump working chambers with...
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RESEARCH OF HYDRAULIC PISTON PUMPS’ START-UP IN LOW AMBIENT TEMPERATURES
PublikacjaStarting hydraulic pumps in low ambient temperatures may cause: decreased hydraulic-mechanical efficiency, larger vibration of hydraulic installation, faster wear and more frequent damage to the elements of pumps, change of material properties of elements, increase of pressure drop. As a result of increase of resistance of cold oil flow in the suction pipe, large underpressure may be experienced, causing incomplete filling of pump...
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Use of waste heat to improve the conditions of the piston engines start up
PublikacjaZespoły prądotwórcze z tłokowymi silnikami spalinowymi są obecnie powszechne stosowane jako awaryjne źródła energii elektrycznej albo elektrownie uzupełniające niedobory energii czy stabilizujące częstotliwość. Ich czas rozruchu powinien być krótki - poniżej 5 minut w przypadku dużych mocy. Zużycie silnika, zużycie paliwa i emisji spalin są silnie uzależnione od stanu cieplnego przed rozruchem. Przedstawiono pomiary laboratoryjne...
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A Concept for Safe and Less Expensive Acceleration of a Marine Steam Turbine Start-up
PublikacjaThis paper analyses the issue of accelerated start-up of a marine steam turbine, which is an important problem because the start-up of a steam machine involves the combustion of fuel that is not transformed into useful energy. To find novel technologies that offer improvements in this aspect is essential due to restrictions on reducing ship emissions. Thus, the shorter the start-up time, the better for the environment and economy....
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Slowly-closing valve behaviour during steam machine accelerated start-up
PublikacjaThe paper discusses the state of stress in a slowly-closing valve during accelerated start-up of a steam turbine. The valve is one of the first components affected by high temperature gradients and is a key element on which the power, efficiency and safety of the steam system depend. The authors calibrated the valve model based on experimental data and then performed extended Thermal-FSI analyses relative to experiment. The issue...
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Volumetric and torque efficiency of pumps during start-up in low ambient temperatures
PublikacjaThe volumetric, torque and total efficiency of hydraulic pumps change during start-up in low ambient temperatures, as well as in thermal shock conditions, un-til they reach the set conditions. The time to reach steady-state conditions de-pends on many parameters: ambient temperature, flow rate, fluid temperature, design of hydraulic units. The author carried out tests of hydraulic pumps in the Hydraulics Laboratory of the Faculty...
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A fast start-up of the organotrophic anammox process inoculated with constructed wetland sediment
PublikacjaOrganotrophic anaerobic ammonium oxidation (anammox) bacteria can utilize small volatile fatty acids with nitrate as electron acceptors with less energy consumption and no biomass production. To achieve a faster and stable start-up of organotrophic anammox process, in this study, the growth of organotrophic anammox bacteria seeded from hybrid constructed wetland (CW) sediment under different TOC/TN ratios and different chloramphenicol...
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Business angels jako alternatywne źródło finansowania start-upów
PublikacjaPodmioty gospodarcze jako element każdego modelu gospodarki są bardzo istotne z punktu widzenia funkcjonowania każdego systemu ekonomicznego na świecie. Stan gospodarki jest bowiem silnie zależny od dynamicznego rozwoju sektora przedsiębiorczości. Zależność ta zachodzi na wszystkich etapach rozwoju gospodarczego, może ona jednak przybierać różne nasilenie i charakter. W Polsce, podobnie jak na całym świecie, powstaje wiele nowych...
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Simulation of large thrust-bearing performance at transient states, warm and cold start-up
PublikacjaThe start-up of a large hydrodynamic thrust bearing of a vertical hydrogenerator is one of the most critical situations during the lifetime of a bearing. Hydrodynamic load capacity is low due to low speed and higher thermal deformations of the pad. A new approach to the simulation of a hydrodynamic bearing is shown in this article. A combination of finite elements method and computational fluid dynamics is used to perform the transient...