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81.
This paper examines the relationship between innovation performance and employment growth in firms by taking a closer look at specific innovation activities and industry effects in the context of the services sector. Firm-level CIS data on Polish services firms in 2004–2009 are analysed using robust M-estimation. The results indicate that the effects of product, process and organisational innovations depend strongly on the level of technological opportunities in the industry in question. Given the widely acknowledged role of marketing innovations in services, possible synergies between innovations in the form of new products and new marketing techniques are also analysed. We demonstrate that marketing innovations are conducive to firm growth if they complement product innovations, but they are less likely to foster growth when applied in isolation. 相似文献
82.
83.
Krzysztof Dmitruk Marcin Denkowski Michał Mazur Paweł Mikołajczak 《Signal, Image and Video Processing》2017,11(4):613-620
Dual-energy X-ray imaging has a vast range of application in security. Luggage inspection is an essential process for an airplane or court house security as well as securing mass events. An image of a content of some package may help to figure out if there is any dangerous object inside and avoid possibly threatening situation. As the raw X-ray images are not always easy to analyze and interpret, some image processing methods like an object detection, a frequency resolution increase or a pseudocoloring are being used. Since color can be a powerful tool to improve the usefulness of an information display, we propose pseudocoloring improvement by modifying material-based approach with edge detection to fill and sharpen color layers over the image making it easier to read and analyze. We demonstrate the effectiveness of the methods using real data, acquired from a professional dual-energy X-ray scanner. 相似文献
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85.
Łukasz Szabłowski Jarosław Milewski Krzysztof Badyda Jakub Kupecki 《International Journal of Hydrogen Energy》2018,43(6):3555-3565
The idea of control strategy of SOFC operating to meet demand of a public utility building was presented. The strategy was formulated with the support of Artificial Neural Network. The network was used to predict the demand for electricity. The calculations were carried out on the example of a building of the Institute of Heat Engineering Warsaw University of Technology. The control strategy is influenced by various factors depending on changes in market conditions and operating characteristics of the cell. We can define different objective functions eg: working for own needs, for maximum profit and maximum service life. The article presents a simulation of SOFC operation for demand profile of the IHE building from the selected time period. 相似文献
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87.
Guo Jianmei Liang Jia Hui Shi Kai Yang Dingyu Zhang Jingsong Czarnecki Krzysztof Ganesh Vijay Yu Huiqun 《Software and Systems Modeling》2019,18(2):1447-1466
Software and Systems Modeling - A key challenge to software product line engineering is to explore a huge space of various products and to find optimal or near-optimal solutions that satisfy all... 相似文献
88.
This paper presents an exergy analysis of SNG production via indirect gasification of various biomass feedstock, including virgin (woody) biomass as well as waste biomass (municipal solid waste and sludge). In indirect gasification heat needed for endothermic gasification reactions is produced by burning char in a separate combustion section of the gasifier and subsequently the heat is transferred to the gasification section. The advantages of indirect gasification are no syngas dilution with nitrogen and no external heat source required. The production process involves several process units, including biomass gasification, syngas cooler, cleaning and compression, methanation reactors and SNG conditioning. The process is simulated with a computer model using the flow-sheeting program Aspen Plus. The exergy analysis is performed for various operating conditions such as gasifier pressure, methanation pressure and temperature. The largest internal exergy losses occur in the gasifier followed by methanation and SNG conditioning. It is shown that exergetic efficiency of biomass-to-SNG process for woody biomass is higher than that for waste biomass. The exergetic efficiency for all biomass feedstock increases with gasification pressure, whereas the effects of methanation pressure and temperature are opposite for treated wood and waste biomass. 相似文献
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90.
Rafal M. Molak Krystian Paradowski Tomasz Brynk Lukasz Ciupinski Zbigniew Pakiela Krzysztof J. Kurzydlowski 《International Journal of Pressure Vessels and Piping》2009,86(1):43-47
The aim of this study was to measure the mechanical properties of weld material taken from a single weld bead laid down on a 316L steel plate. Due to the low available volume of weld material, microsamples with a total length of 5.5 mm were used. The Digital Image Correlation method (DIC), which enables measurement of mechanical properties of very small samples, was employed for the strain measurements in a uniaxial tensile test. Samples were cut out from three different zones of the specimen: plate, weld, and the heat affected zone. The material from heat affected zone showed the highest value of the Ultimate Tensile Strength (UTS) (580 ± 7 MPa) and yield strength (339 ± 6 MPa). Plate material had lower UTS (559 ± 5 MPa) and yield strength (304 ± 7 MPa). The lowest values of UTS (526 ± 6 MPa) and yield strength (291 ± 8 MPa) have been revealed for the weld. The values obtained for UTS, yield strength and elongation to failure for the plate material were compared with data obtained using standard test specimens. No significant differences between results obtained for the microsamples and standard samples have been found. 相似文献