This study builds on an existing structural model developed to examine the influence of

leadership and organizational culture on innovation and satisfaction of engineers in Australian

public sectors (APS). The objective of this study is to increase the understanding of

innovation process with a focus on causal relationships among critical factors. To achieve this

objective, the study develops an assessment approach to help predict creativity and work

meaningfulness of engineers in the APS. Three quantitative analysis methods were sequentially

conducted in this study including correlation analysis, path analysis, and Bayesian

networks. A correlation analysis was conducted to pinpoint the strong association between

key factors studied. Subsequently, path analysis was employed to identify critical pathways

which were accordingly used as a structure to develop Bayesian networks. The findings of

the study revealed practical strategies for promoting (1) transformational leadership and (2)

innovative culture in public sector organizations since these two factors were found to be key

drivers for individual creativity and work meaningfulness of their engineers. This integrated

approach may be used as a decision support tool for managing the innovation process for

engineers in the public sectors.

Most countries in the world are facing two major challenges, one is the increase in the demand for energy consumption difficult to fulfill because of limited fossil fuel, and the second is the emission norms specified by many countries. Various methods are adopted to reduce emissions from engines but that leads to sacrificing the performance of CI engines. To eradicate this problem in the present study, the nanoparticles like (TiO2) are used with different particle sizes 10–30 nm, 30–50 nm and 50–70 nm induced in B20 (20% biodiesel and 80% diesel) with the constant volume fraction of 100 ppm, and utilized in the diesel engine without any modifications. The results showed that the incorporation of TiO2 nanoparticles improves the combustion of hydrocarbons and reduces the emissions of CO, unburned hydrocarbon concentration, NOx and soot. Moreover, among three sizes of the nanoparticles, those with size 30–50 nm showed interesting results with the reduction in brake-specific energy consumption, NOx, smoke and HC by 2.9%, 16.2%, 35% and 10%, respectively, com-pared to other blends used in the study, and hence the blend with the nanoparticle of size 30–50 nm is expected to be a more promising fuel for commercial application in CI engines.

In the paper, the Author presents the method of realisation of various scenarios of "test ride" on engine test bench. Research possibilities offered by semi-virtual system consisting of a real engine and a vehicle simulator are described. The previous article by the Author, "The Principles of Engine Operation Simulation in Test-bench Examination in the Conditions Equivalent to Traffic Exploitation of the Vehicle" [7] was devoted to the description of test requirements. Test accuracy, structure and equipment of the test stand were described there, as well as the characteristics of the software that controls the test and monitors its correctness.

The paper presents an original design of a single compression machine for combustion study. The principle of operation is based an old concept, utilizing the inertia energy of a flywheel to accelerate the crank mechanism and the attached piston to compress rapidly the combustible mixture in the combustion chamber. A square piston geometry was adopted to allow visualization of the compression and combustion processes in directions perpendicular to the cylinder axis. To avoid the extensive scratching of glass walls by the moving piston, a special multi-action clutch-brake unit was used; this facilitates coupling of the flywheel with the crank mechanism during the single piston stroke and subsequent immediate uncoupling and fast stopping of the piston. The whole operating cycle can be completed within no more than two revolutions of the crankshaft. The design details of the machine, its acceleration characteristics and a sample of the visualized combustion process are presented.

The paper presents a general idea of the acceleration test method and the design, construction and testing of the inertial dynamorneter test rig developed for small, high performance two-stroke engines. The method is universal and can be also used for four-stroke engines but it is especially useful for the two-stroke ones. The testing procedure is described and the advantages of that type of investigation method are pointed out. It has been proved that the reliability of the method is satisfactory. It was also proven that the individual construction of the inertial dynamorneter of good quality can be performed individually and that it can be a very useful investigation tool in engine tuning practice. The point has been stressed that the major advantage of that method is the possibility of the instantaneous measurement of the engine power characteristic during unsteady engine operation (acceleration) where the time for the single run does not exceed ten seconds.

This article presents shortly reasons for improving designs of turboprop and turboshaft engines, and describes aero-thermodynamic aspects of methods or modification of these devices. The theoretical analysis of methods or modification concerns general changes or efficiency, flow, and rating. The influence of the following factors on engine performance is presented: change of efficiency or engine units, increase of compression and flow rate by using a compressor zerostage, change of compressor pressure ratio, changes of gas temperature keeping the gasgenerator rotational speed constant by adjusting the minimal throat area of turbine nozzle guide vanes, turbornachinery modelling, and changes of rotational speed of ratings.

The article concerns computer modelling of processes in cooling systems of internal combustion engines. Modelling objectives and existing commercial programs are presented. It also describes Author’s own method of binding graphs used to describe phenomena in the cooling system of a spark ignition engine. The own model has been verified by tests on the engine dynamometer. An example of using a commercial program for experimental modelling of an installation containing a heat accumulator is presented.

Replacing silicon with diamond may significantly reduce energy losses in electronic devices, according to Dr. Michał Pomorski from the CEA-LIST Diamond Sensors Laboratory in France.

Plastic rocks can creep, therefore the knowledge of the rheological properties of the drilled formations is an important element of the drilling process and when choosing borehole designs. These properties of plastic formations also influence the way in which appropriate drilling technology and drilling mud properties are selected. The article presents the effect of basic rheological parameters of salt from the Fore-Sudetic Monocline deposit on the drilling of boreholes in the mining area of KGHM Polska Miedź, which in the future can be used as a good drilling practice to improve the safety and efficiency of drilling.

The process of drilling in plastic rocks may be hindered. Salt is a plastic rock and in the analyzed rock mass it is deposited at a considerable depth. The caprock exerts big loads on it, beside the temperature in the deposit intensifies the rheological properties of the rock. The creep process causes that the borehole contracts, therefore the knowledge about the rheological properties of the drilled rock is very important for establishing the safe time in which the well may remain uncased. The paper is devoted to the influence of basic rheological parameters of salt bed in the Fore-Sudetic Monocline on the process of drilling of a borehole in the area of KGHM Polska Miedź as these data can be used in drilling practice in the future.

This paper presents an experimental study on the leaching of heavy metals, toxic chemicals and persistent organic pollutants (POPs) – PAH, PCB and HCB – from soil dredged from the coastal area of Västernorrland in northern Sweden. The soil was stabilized with cement/slag. Samples were subjected to modified surface leaching and shake tests using technical standards of the Swedish Geotechnical Institute (SGI). The experiments were performed using different blends of binding agents (30/70, 50/50, 70/30) and binder quantities (120 and 150 kg/m3) to analyze their effects on leaching. Soil properties, tools, and workflow are described. Binders included Portland cement and ground granulated blast furnace slag (GGBFS). Samples were tested to evaluate the min/max contents of pollutants (μg/l) for heavy metals (As, Ba, Pb, Cd, Co, Cu, Cr, Hg, Mn, Mo, Ni, S, V, Zn) and the hydrocarbon fraction index in the excess water. The leaching of heavy metals and POPs was assessed in sediments after the addition of the binder. The comparison was made against the two mixes (cement/slag in 30/70% and high/low binder with low/high water ratio). The results showed that 70% slag decreases the leaching of heavy metals and POPs. The equilibrium concentrations of DOC and heavy metals at L/S 10 (μg/l) were measured during the shake experiments to compare their levels in the groundwater that was used as a leachate. The leached content was assessed at L/S 10 in the upscaling experiments using four samples for PAH, PCB and various fractions of hydrocarbons: C10–C40, C10–C12, C12–C16 and C35–C40. The shake test showed a decrease in the leaching of heavy metals and POP substances from the soil subjected to stabilization by a higher amount of slag added as a binder. A binder blend with 30% cement and 70% of GGBFS showed the best performance.

At the beginning of the year 2024, 65 years will have passed since the establishment of the Chamber of Experts of the Association of Polish Electrical Engineers (SEP). During this period, SEP underwent significant changes. Particularly serious changes in the conditions for practicing association expertises have occurred in recent years, along with dynamic economic and political changes in Poland. Expertise is strongly based on economic conditions and the ways in which scientific, technical and industrial competences are expanded and available in the society. In the past, these highest competencies were quite strictly limited to well-organized professional communities related to scientific and technical associations such as SEP, and federal bodies such as NOT. Competencies were also generated in the best industrial centres associated with academic polytechnic centres. Today the role of expertises in electrical, electronics and ICT engineering is undergoing significant changes.

The engine simulations have become an integral part of engine design and development. They are based on approximations and assumptions. The precision of the results depends on the accuracy of these hypotheses. The simplified models of frozen composition, chemical equilibrium and chemical kinetics provide the compositions of combustion products for engine cycle simulations. This paper evaluates the effects of different operating conditions and hypotheses on the exergetic analysis of a spark-ignition engine. The Brazilian automotive market has the highest number of flex-fuel vehicles. Therefore, a flex-fuel engine is considered for simulations in order to demonstrate the effects of these different hypotheses. The stroke length and bore diameter have the same value of 80 mm. The in-cylinder irreversibility is calculated for each case at the closed part of the engine cycle. A comparative analysis of these hypotheses provides a comprehensive evaluation of their effects on exergetic analysis. Higher values of accumulated irreversibility are observed for the oversimplified hypothesis.

Thermoacoustic converters are devices for direct conversion of acoustic energy into thermal energy in the form of temperature difference, or vice versa – for converting thermal energy into an acoustic wave. In the first case, the device is called a thermoacoustic heat pump, in the second – thermoacoustic engine. Thermoacoustic devices can use (or produce) a standing or travelling acoustic wave. This paper describes the construction and properties of a single-stage thermoacoustic engine with a travelling wave. This kind of engine works using the Stirling cycle. It uses gas as a working medium and does not contain any moving parts. The main component of the engine is a regenerator equipped with two heat exchangers. Most commonly, a porous material or a set of metal grids is used as a regenerator. An acoustic wave is created as a result of the temperature difference between a cold and a hot heat exchanger. The influence of working gas, and such parameters as static pressure and temperature at heat exchanger on the thermoacoustic properties of the engine, primarily its efficiency, was investigated. The achieved efficiency was up to 1.4% for air as the working medium, which coincides with the values obtained in other laboratories. The efficiency for argon as working gas is equal to 0.9%.

This article proposes an analytical model of a system with priorities servicing a mixture of different elastic traffic streams. The model presented in the article was developed as the extension of earlier works published by the authors. It utilizes the concept of equivalent bandwidth and then, following bandwidth discretization, uses the dependencies introduced on the basis of the assumptions adopted for the generalized Kaufman-Roberts formula and for the model of a full-availability group with traffic compression. The article presents a possibility of using the proposed model to model the radio interface in a multi-service mobile network and provides an example of the above with the interface of an LTE network. Since the proposed model is an approximate one, the results of the calculations are compared with the results of simulations. A comparison of the results confirms an acceptable level of accuracy of the model. The model can be successfully used in the analysis and design of links and nodes of telecommunication and computer networks.

The time period of a jet engines full acceleration (from idle run rotating speed to full thrust) is a very important operational parameter. Minimization of this period is an important problem to be solved during the design of the fuel supply and control system. There are many methods of acceleration process control, especially in the case of engines with complicated design configurations. This work presents the problem of acceleration of a simple, single spool turbine jet engine with a so-called stable geometry, in which only one input (control) signal exists - fuel flow rate. Two methods of acceleration control consisting of limitation of the maximum allowable temperature of working medium in front of and behind the turbine in transient states were analyzed. In order to avoid difficulties associated with the direct measurement of actual temperatures, the so-called nonlinear engine observer was applied. With the use of the computer simulation method it was proven that the control algorithm with the limited maximum temperature in front of the turbine makes it possible the shortening of the acceleration time period significantly in comparison with a similar algorithm, that realizes the limitation of temperature behind the turbine.

Many groups of researchers have focused on the design of micro turbine engines in recent years. Since turbo-component efficiency becomes very low due to the downsizing effect, an important problem arises of how to obtain thermal efficiency high enough to produce the positive power required. The micro wave rotor is expected to be applied for the improvement of the performance of ultra micro gas turbines, increasing the cycle pressure ratio. Wave rotors can also be built in another configuration. Applying only a combustion chamber and using oblique blades to form the rotor cells, net power can be taken from the rotor. In that way, the use in a micro scale of an inefficient turbo unit can be omitted. Such a solution in a form of wave engine was developed and practically realised by Weber [ 15] and Pearson [8], [9], [ IO] in centimetre scale. Conventional construction of wave engines in a form of wave rotor can not be directly realized in MEMS technology. The new idea of a wave disk developed by Piechna, Akbari, Iancu,and Mueller [II] and independently by Nagashima and Okamoto [7] gives the possibility of easy implementation of the wave engine idea in MEMS technology. In the proposed solution, the wave disk plays the role of an active compressiondecompression unit and torque generator. Appropriate port geometry with oblique blades forming the disk channels generates torque. The engine disk rotates with a speed much lower than the conventional turbo-unit that simplifies the bearing problem. Also, the construction of electric generator can be simpler. The paper presents the proposed flow schemes, thermodynamic cycle, exemplary engine construction and some results of simulation of the MEMS wave engine using the wave disk.

The paper presents the results of measurements carried out in the GTM400 turbojet engine with a changed combustion chamber geometry. The available publications lack more detailed information on the temperature distribution in evaporators, which are part of the combustion chamber of small turbojet engines. As the results of the analysis showed, this is not simple, because the research takes place in very small spaces. The reason for the work carried out is to check whether the temperatures in the evaporators are high enough. This allows to determine whether the fuel is evaporating properly. Therefore, an analysis was carried out to determine the temperature distribution in the area of the inlet to the evaporator. Thanks to the modification of the combustion chamber, it was possible to measure temperatures, which in the engine literature are simulated using numerical analysis. The analysis described in the paper is one of the stages of preparing the engine for operation with hydrogen. It is modified as part of a project to build a hybrid engine burning traditional JET-A1 fuel and alternative fuel, i.e. hydrogen.

The article presents subject matter related to the assessment of the suitability of the built-up area, including the occurrence of sinkholes on the surface. The investment plot, which is the subject of the analysis, is located in the central part of the Upper Silesian Coal Basin, where shallow exploitation of coal seams was conducted in the past. At present it is a post-mining area, located at a large distance from active mines. It has an attractive administrative location and good transport connection with the main road connecting the cities of the Silesian agglomeration. These advantages make it particularly attractive in terms of use for various types of investments. The geological and mining factors are not favorable in the area in question, mainly due to the shallow mining exploitation conducted in the past and the access excavations on small depth and an unknown method of liquidation. These reasons are the cause of some restrictions in the use of construction, for which taking the appropriate solutions is recommended. According to the study of (Rules... 2009), the category of mining land should be defined for the areas of liquidated mining plants due to the limitation in construction use. The authors of the article made an attempt to determine it, and they analyzed the geological and mining conditions for this purpose, mainly including mining exploitation conducted in the past. On the basis of the obtained results and own experience, the type of expected hazards and its assessment were determined The probability of the occurrence of the inclusions according to the Chudek-Olaszowski method (Chudek et al. 1988) was assumed as a measure of the hazard.

This paper aims to evaluate the effects of blended binders on the development of strength in moraine soils by optimising the proportion of several binders. We tested three types of soil as a mixture of moraine soils: A (sandy clay), B (clayey silt) and C (silty clay), collected in southern Sweden. The soil was compacted using a modified Proctor test using the standard SS-EN 13286-2:2010 to determine optimum moisture content. The particle size distribution was analysed to determine suitable binders. The specimens of types A, B and C, were treated by six different binders: ordinary Portland cement (OPC); hydrated lime (Ca(OH)2); ground granulated blast furnace slag (GGBFS) and their blends in various proportions. The strength gain in soil treated by binders was evaluated by the test for Unconfined Compressive Strength (UCS) against curing time. For soil type A, the strength increase is comparable for most of the binders, with the difference in behaviour in the UCS gain. The OPC/lime, GGBFS and hydrated lime showed a direct correlation, while OPC, OPC/GGBFS and GGBFS/hydrated lime – a quick gain in the UCS by day 28th. After that, the rate of growth decreased. Compared to soil type A, Ca(OH)2 performs better on the stabilisation of soil type B. Besides, the hydrated lime works better on the gain of the UCS compared to other binders. The GGBFS/Ca(OH)2 blend shows a notable effect on soil type A: the UCS of soil treated by Ca(OH)2 performs similarly to those treated by OPC with visible effects on day 90th. Cement and a blend of slag/hydrated lime demonstrated the best results for soil type B. An effective interaction was noted for the blends GGBFS and hydrated lime, which is reflected in the UCS development in soils type A and B. Blended binder GGBFS/hydrated lime performs better compared to single binders.

The paper presents a new method of determination of economic benefits of land consolidation of farms, which result from reduction of land parcels' number. A model method and a logical method have been applied. The discussed economic benefits have been determined by means of comparing economic evaluation of a model farm's land configuration before and after land consolidation. As a result of analysis, a mathematical formula that describes an economic benefit of land consolidation, resulting from the reduction of land parcels number, has been derived. The economic benefit is a function of the differences between the numbers of arable fields and the differences between the area of an arable lands and green lands of a farm, before and after land consolidation, as well as constant parameters and slope of linear regression equations for the models of such fields. The benefit does not depend on the area of farms.

ln laboratory electrically heated entrained flow reactor with quasi one-dimensional laminar flow the influence of fuel properties on the nitrogen oxide emission for 23 coals of various rank from brown coal, bituminous coal to anthracites has been examined. For one brown coal type twofold increase of nitrogen content resulted in NO, emissions increase of about 30%. Increasing rank from brown coal to bituminous coal increases NO emissions and next a fall in the anthracites range. With nitrogen content increase NO - emission grows a~d the ratio of fuel nitrogen conversion to nitrogen oxide decreases. Experiments results and their statistical analysis were used to determine relationships describing NO, emissions and conversion ratio of fuel nitrogen to nitrogen oxide as functions of two variables. describing coal properties, i.e. nitrogen content and fuel ratio (fixed carbon to volatile matter ratio).

AISI 316L steel was subjected to nitrocarburizing under glow discharge conditions, which was followed by DLC (diamond-like carbon) coatings deposition using the same device. The coatings were applied under conditions of direct current and pulsed glow discharge. In order to determine the influence of the produced nitrocarbon austenite layer and the type of discharge on the microstructure and mechanical properties of the coatings, the following features were analysed: surface roughness, coating thickness, structure, chemical composition, adhesion and resistance to frictional wear. For comparison purposes, DLC coatings were also deposited on steel without a nitrocarburised layer. The obtained results indicate a significant influence of the type of glow discharge on the roughness, hardness, nitrogen content and of the nitrocarburised layer on the resistance to wear by friction and adhesion of the produced coatings.

The paper presents the assumptions and methodology for investigating equivalent heat load testing of hot aircraft engine components. The basic heat loads occurring in an aircraft engine during aircraft flight are characterised. Diagrams of the proposed heat loads are presented, together with the number of cycles, and a test bench is characterised and shown to enable equivalent heat load testing of aircraft engine components.