The dynamics of the social, economic and legal changes which took place from 2004 to 2014 related to Poland’s accession to the European Union has changed our reality and the functioning of the state ...and its institutions, including museums. New possibilities have arisen, together with serious challenges which museum managers and museum professionals have had to face. The National Institute for Museums and Public Collections, established in 2011, has become the organiser of the prestigious Sybilla Museum of the Year Contest, in line with its founding principles. Its organisers decided to carry out open consultations with museum professionals, which has resulted in changes to the regulations for new contest categories, pertaining for example to sources of financing an institution with European funds, and implementing new technological solutions by museums. The growing availability of new technologies has contributed to a new category in the contest “Digitisation and new media”, which appeared for the first time in the regulations for the 34th edition of the Sybilla contest in 2013. The process of technological revolution also applies to museums, as new technologies are present at museum conservation workshops, research papers, exhibition premises and educational activities. Museums use diverse electronic communication solutions, such as websites, applications and social media. Digital technologies are being used on an unprecedented hitherto scale to document and share collections, and to disseminate knowledge about them. During the latest, 37th edition of the Sybilla contest in 2016, a unique project was awarded: the Gulf of Gdańsk Shipwreck Virtual Open-Air Museum. Recording and Inventory of Underwater Archaeological Heritage, carried out by the National Maritime Museum in Gdańsk. An innovative method for submarine documentation, in the form of the photogrammetry of 3D models of shipwrecks from the Gulf of Gdańsk, is being developed as part of the project. Faras in Wikipedia is a featured project by the National Museum in Warsaw. It consists of creating a knowledge database about the Faras Gallery, about the relics of Nubian art which form part of the museum’s collections, and the archaeological expedition and researchers involved, as well as making it available to the readers of Wikipedia and Internet users in Poland and abroad.
This article presents examples of numerical simulations done based on the real experiments of S700MC steel T-joint laser and hybrid welding. Presented results of numerical analyses carried out using ...SYSWELD show the possibilities offered to contemporary engineers by modern software used to make numerical analyses of production processes. After calibration of a heat source models on the chosen examples of S700MC steel 10-mm-thick T-joint laser and hybrid welding, distributions of temperature fields, thermal cycles, distributions of individual metallurgical phases and hardness, and strains and plastic deformations in simulated processes were calculated for one selected joint from both mentioned methods. The results of the analysis allow determining both the differences in the stress distributions and their minimal and maximal values. This article also presents the benefits resulting from the use of such analyses, due to the significant savings in time and resources to be spent on the development of correct technologies for joining modern construction materials such as thermomechanically treated steels, especially given that some of the results are unavailable or very difficult to collect using conventional measurement methods.
Assuring high quality of welded joins is a vital task in many industrial branches also when joints are made manually. It is the case metal-arc welding with covered electrode. One of main ...imperfection, that can occur in this process is slag inclusion. In the paper an method for detection of slag inclusion in multipass manual welding is proposed and validated. The key idea of the method is that small temperature disturbances will be noticeable in consecutive cross-section of joint in the cooling pass. Temperature distribution weld face was measured with longwave infrared camera (LWIR). For consecutive cross-section made in IR representation of joint differences in mean temperature was calculated to assess the cooling rate directly after the elements were welded. It can be made because on each thermogram the whole joint is visible, thus position of electrode in time can be easily marked. Results of slag inclusion detection were compared with radiographic images of made joints. In the future additional studies will be performed in order to generalize proposed method to wider group of materials and for more complex welds.
The research work and related tests aimed to identify the effect of filler metal-free laser beam welding on the structure and properties of butt joints made of steel 700MC subjected to the TMCP ...(thermo-mechanically controlled processed) process. The tests involved 10-mm thick welded joints and a welding linear energy of 4 kJ/mm and 5 kJ/mm. The inert gas shielded welding process was performed in the flat position (PA) and horizontal position (PC). Non-destructive testing enabled classification of the tested welded joints as representing the quality level B in accordance with the requirements set out in standard 13919-1. Destructive tests revealed that the tensile strength of the joints was 5% lower than S700MC steel. The results of tensile tests and changes in structure were referred to joints made using the MAG (Metal Active Gas) method. The tests of thin films performed using a high-resolution scanning transmission electron microscope revealed that, during laser beam welding, an increase in dilution was accompanied by an increase in the content of alloying microadditions titanium and niobium, particularly in the fusion area. A significant content of hardening phases in the welded joint during cooling led to significant precipitation hardening by fine-dispersive (Ti,Nb)(C,N) type precipitates being of several nanometres in size, which, in turn, resulted in the reduction of plastic properties. An increase in the concentration of elements responsible for steel hardening, i.e., Ti and Nb, also contributed to reducing the weld toughness below the acceptable value, which amounts to 25 J/cm
. In cases of S700MC, the analysis of the phase transformation of austenite exposed to welding thermal cycles and the value of carbon equivalent cannot be the only factors taken into consideration when assessing weldability.
The article presents results of tests concerning the effect of technological parameters of the plasma arc cutting process (involving the use of air as plasma gas) on the quality of cut surfaces as ...well as on structural transformations and changes in the chemical composition of 14 mm-thick plates made of steel S235JR. The tests revealed that the adjustment of optimum parameters of the cutting process enabled the obtainment of cut surfaces representing quality class I in accordance with the ISO 9013 standard. Only the surfaces processed using the maximum cutting rates represented quality class II. The chemical composition analysis was performed using an ICXA 733 X-ray microanalyser (Jeol) equipped with an energy-dispersive spectrometer (EDS) and an ISIS 300 analytical system (OXFORD). The cut surfaces were observed and their characteristic areas were photographed using an X-ray microanalyser and the backscattered electrons (BSE) technique. The phase analysis was performed using a PHILIPS PW 1050 X’Change machine operated in the B–B (Bragg–Brentano) geometry. It was observed that the application of the air plasma cutting process led to the formation of an amorphous phase on the cut surface. The amorphous phase was characterised by a very high nitrogen content (of approximately 1.6%) and a hardness of 750 HV 0.2. The intense nitration resulted from the diffusion of nitrogen from the plasma gas. At the same time, the effect of air plasma arc gases on the liquid metal was responsible for the carburising of the cut surface (up to approximately 0.5%) and the burnout of alloying components (in accordance with the theory of the selective oxidation of chemical elements). The quality of the cut surfaces was primarily affected by the cutting rate. An increase in the cutting rate was accompanied by the deterioration of the geometric features of cut surfaces. In addition, higher cutting rates also translated into the significant reduction of the HAZ width and that of the size of the zone of chemical composition changes. The tests revealed that, in terms of the 14 mm-thick plates made of steel S235JR, the optimum cutting rates were restricted within the range of 600 mm/min to 1500 mm/min. The tests carried out made it possible to determine the influence of the active plasma gas (oxygen, nitrogen) both on changes in the chemical composition of the tested steel and on the quality of the cut surfaces obtained.
The article presents tests aimed to verify the possibility of Thermomechanically Controlled Processed (TMCP) steels T-joints laser welding. The 10 mm thick high-yield-point steel S700MC obtained in ...an industrial manufacturing process was used for tests of laser welding. The joints made during the tests were single- and double-sided. Subsequent nondestructive tests revealed that the laser-welded joints represented quality level B in accordance with PN-EN ISO 13919-1. Single-sided welding performed at the output laser beam power of 11 kW provided the penetration depth of just 8 mm without visibly deforming of the joint. The double-sided welded joints were characterized by proper geometry and the presence of gas pores in the welds not compromising the requirements of quality level B (strict requirements). The identified weld structure was bainitic-ferritic. The weld hardness was by approximately 60 HV1 higher than that of the base material (280 HV1). The HAZ (Heat Affected Zone) area was slightly softer than the base material. The tests of thin foils performed using a high-resolution scanning transmission electron microscope revealed that, during welding, an increase in the content of the base material in the weld was accompanied by an increase in contents of alloying microagents Ti and Nb, particularly near the fusion line. The above-named alloying microagents, in the form of fine-dispersive (Ti,Nb)(C,N) type precipitates, could reduce plastic properties of joints.
Arc length is a crucial parameter of the manual metal arc (MMA) welding process, as it influences the arc voltage and the resulting welded joint. In the MMA method, the process' stability is mainly ...controlled by the skills of a welder. According to that, giving the feedback about the arc length as well as the welding speed to the welder is a valuable property at the stage of weld training and in the production of welded elements. The proposed solution is based on the application of relatively cheap Complementary Metal Oxide Semiconductor (CMOS) cameras to track the welding electrode tip and to estimate the geometrical properties of welding arc. All measured parameters are varying during welding. To validate the results of image processing, arc voltage was measured as a reference value describing in some part the process stability.
This article presents production results concerning metal matrix composite-coatings made using the laser-cladding technology. The enhancement of the wear resistance of the material surface is the one ...of the main goals accompanying the manufacturing of composite coatings. Nickel-based superalloys are used in several industries because they are characterized by a number of desirable properties including high tensile and fatigue strength as well as resistance to high-temperature corrosion in aggressive environments. One of the most interesting materials from the group of superalloys is Inconel 625, used as a matrix material in tests discussed in this article. However, nickel-based superalloys are also characterized by an insufficient wear resistance of the surface, therefore, in relation to the tests discussed in this article, Inconel 625-based composite coatings were reinforced by adding 10%, 20% and 40% of titanium carbide particles. The addition of hard phases, i.e., TiC, WC or SiC particles can have a positive effect on the erosion resistance of cladded specimens. The aim of the experiment was to determine the impact of the titanium carbide content on the structure of the alloy and its resistance to corrosive wear, enabling the extension of the service life of Inconel 625/TiC composite coatings. The investigation included microhardness tests, corrosion resistance analysis, penetrant tests, macrostructure and microstructure analyses and X-ray diffraction (XRD) tests. The TiC particles increased the hardness of the coatings and, in general, had a negative impact on the corrosion resistance of pure Inconel 625 coatings. However, the increased homogeneity of composite coatings translated into the improvement of corrosion resistance.
Limited evidence suggests variation in mortality of older critically ill adults across Europe. We aimed to investigate regional differences in mortality among very old ICU patients.
Multilevel ...analysis of two international prospective cohort studies. We included patients ≥80 yr old from 322 ICUs located in 16 European countries. The primary outcome was mortality within 30 days from admission to the ICU. Results are presented as n (%) with 95% confidence intervals and odds ratios (ORs).
Of 8457 patients, 2944 (36.9% 35.9–38.0%) died within 30 days. Crude mortality rates varied widely between participating countries (from 10.1% 6.4–15.6% to 45.1% 41.1–49.2% in the ICU and from 21.3% 16.3–28.9% to 55.3% 51.1–59.5% within 30 days). After adjustment for confounding variables, the variation in 30-day mortality between countries was substantially smaller than between ICUs (median OR 1.14 vs 1.58). Healthcare expenditure per capita (OR=0.84 per $1000 0.75–0.94) and social health insurance framework (OR=1.43 1.01–2.01) were associated with ICU mortality, but the direction and magnitude of these relationships was uncertain in 30-day follow-up. Volume of admissions was associated with lower mortality both in the ICU (OR=0.81 per 1000 annual ICU admissions 0.71–0.94) and in 30-day follow-up (OR=0.86 0.76–0.97).
The apparent variation in short-term mortality rates of older adults hospitalised in ICUs across Europe can be largely attributed to differences in the clinical profile of patients admitted. The volume–outcome relationship identified in this population requires further investigation.
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