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The maritime industry, central to global trade, faces critical challenges related to energy efficiency and environmental sustainability due to significant energy loss from waste heat in marine engines. This review investigates the potential of waste heat recovery (WHR) technologies to enhance operational efficiency and reduce emissions in marine systems. By analyzing major WHR methods, such as heat exchangers, Organic Rankine Cycle (ORC) systems, thermoelectric generators, and combined heat and power (CHP) systems, this work highlights the specific advantages, limitations, and practical considerations of each approach. Unique to this review is an examination of WHR performance in confined marine spaces and compatibility with existing ship components, providing essential insights for practical implementation. Findings emphasize WHR as a viable strategy to reduce fuel consumption and meet environmental regulations, contributing to a more sustainable maritime industry.

The paper presents a new signal generator for charge-pumping. Modular structure of the generator is discussed with special emphasis on signal-generation module consisting of five independent signal channels. Digital signal synthesis is chosen to minimize inaccuracies. Noise analysis is performed to demonstrate the validity of the design of signal channel. Calibration procedure is also discussed.

A model of the position of the edge of emitter-base junction in the base and collector current pre-exponential ideality factor in HBT transistor with a SiGe base is presented. The model is valid for transistors with nonuniform profiles of doping and Ge content. The importance of taking into account the dependence of the effective density of states in SiGe on local Ge content and that of electron diffusion coefficient in SiGe on drift field for modeling accuracy is studied.

A set of physical models describing silicon carbide with fitting parameters is proposed. The theoretical I-V output and transfer characteristics and parameters of MOS transistors were calculated using Silvaco Atlas and Crosslight Apsys semiconductor device simulation environments

This work reports on changes in the properties of ultra-thin PECVD silicon oxynitride layers after high- temperature treatment. Possible changes in the structure, composition and electrophysical properties were investigated by means of spectroscopic ellipsometry, XPS, SIMS and electrical characterization methods (C-V, I-V and charge- pumping). The XPS measurements show that SiOxNy is the dominant phase in the ultra-thin layer and high-temperature annealing results in further increase of the oxynitride phase up to 70% of the whole layer. Despite comparable thickness, SIMS measurement indicates a densification of the annealed layer, because sputtering time is increased. It suggests complex changes of physical and chemical properties of the investigated layers taking place during high-temperature annealing. The C-V curves of annealed layers exhibit less frequency dispersion, their leakage and charge-pumping currents are lower when compared to those of as-deposited layers, proving improvement in the gate structure trapping properties due to the annealing process.

The goal of this work was to study nitrogen implantation from plasma with the aim of applying it in dual gate oxide technology and to examine the influence of the rf power of plasma and that of oxidation type. The obtained structures were examined by means of ellipsometry, SIMS and electrical characterization methods.

Experiments presented in this work are a summary of the study that examines the possibility of fabrication of oxynitride layers for Si structures by nitrogen implantation from rf plasma only or nitrogen implantation from rf plasma followed immediately by plasma oxidation process. The obtained layers were characterized by means of: ellipsometry, XPS and ULE-SIMS. The results of electrical characterization of NMOS Al-gate test structures fabricated with the investigated layers used as gate dielectric, are also discussed.

The history of semiconductors is presented beginning with the first documented observation of a semiconductor effect (Faraday), through the development of the first devices (point-contact rectifiers and transistors, early field-effect transistors) and the theory of semiconductors up to the contemporary devices (SOI and multigate devices).

Extensive numerical simulations of FinFET structures have been carried out using commercial TCAD tools. A series of plasma etching steps has been simulated for different process conditions in order to evaluate the influence of plasma pressure, composition and powering on the FinFET topography. Next, the most important geometric parameters of the FinFETs have been varied and the electrical characteristics have been calculated in order to evaluate the sensitivity of the FinFET electrical parameters on possible FinFET structure variability.

This article seeks to contribute to the current debate on the new definition of the “museum” – a debate which led to turmoil at the 2019 ICOM General Assembly in Kyoto. With reference to the case study of the Museum of the Second World War in Gdansk (MSWW), it analyses the new and very successful genre of the narrative museum, a genre which arguably fulfils the core elements of the definition currently being discussed by ICOM. In this regard, it brings into focus the paramount importance of community involvement in creating and managing narrative museums – an aspect that has been virtually absent in the academic and media debates over the nature of the MSWW and its programme. By pointing out the fragility of the foundations for such participation, based solely on trust between communities, the museum, and state authorities, this article calls for and provides guidance for an academic and institutional redefinition of the narrative museum and the institution of a museum in general.

The scientific aim of this paper is to analyse the topicality of the turbocharger explosions and to attempt to answer the question of whether some technical characteristics of the engine can be perceived as directly connected with the risk of the turbocharger explosion. Moreover, our objective was also to calculate the turbocharger explosion probability. This article presents the results of a quantitative and qualitative analysis of 42 explosions of marine main engine turbochargers occurring between 1977 and 2022. The number of explosions was analysed, and the average and instantaneous frequencies of turbocharger explosions each year were determined. An analysis was performed of the number of explosions with respect to the age and type of ship on which the accident occurred. An analysis of the contribution of different types of main engine to the studied population of explosions was also carried out. Criteria such as the number of strokes, engine speed, type of crank-piston mechanism, cylinder arrangement, engine power per cylinder, and number of cylinders were considered. An analysis was carried out of the disasters that had occurred, considering the contribution of the various engine manufacturers. An integrated distribution of the number of turbocharger explosions by year was presented, considering the engine speed, the maximum continuous rating of the engine, and the engine design. The analysis did not indicate a significant correlation between the type of ship and the number of explosions that occurred. More than half of the analysed population of explosions (median) occurred on vessels no older than 15 years. It is highly likely that engine type does not directly affect the number of turbocharger explosions and the risk of explosions. On the other hand, it is not possible to exclude the influence of the individual characteristics of an engine built to a particular manufacturer’s design on the magnitude of the risk of a turbocharger exploding during engine operation. Considering the number of ships worldwide, the probability of an explosion in a given year on a given ship is not less than 1.61 × 10−7.

Based on available sources, the frequency of explosions in the marine engine’s starting air manifolds is determined under real conditions. A cause-and-effect analysis of these explosions and their root causes are identified. A probabilistic model of an explosion in the starting air manifold of a marine engine is built using a fault tree analysis (FTA). Using a stochastic simulation (Monte Carlo) and an exact reliability availability calculation (ERAC) algorithm applied to the developed FTA model, selected reliability measures are calculated to describe an incident of the top event, which involves an explosion in the starting air manifold. For such an event, several factors are calculated, including the availability, the unavailability, the failure frequency, and the mean time to failure. Based on the simulations, the relative frequency of the top event is determined in relation to the number of events that can simultaneously occur and lead to an explosion. The significance of each basic event is assessed to determine their individual impact on the explosion incident. The following measures are used: the Vesely–Fussell measure of importance, the criticality measure of importance, the Birnbaum measure of reliability importance, and the Birnbaum measure of structural importance. The results of the analysis show that defective starting air valves are most responsible for the explosion incident in the starting air manifold. During the first year of the ship’s operation, the reliability does not fall below the value of 0.65, while the mean time to failure and the top event frequency are statistically at the level of one explosion per approximately 2.28 years of continuous engine operation.

Research of breakage of the chestnut tree branch on the planting of university campus is provided. Collapse is caused by a severe accidental wind gust. Due to collapse in the student environment, the investigation has additional methodical value for the teaching of FEA simulation. The model includes roots, trunk, branch, and conditional crown, where the trunk-branch junction is steady enough. The load-bearing system of tree is taken as an example of an effective bionic design. The branch has grown with the implementation of the idea of “equal-strength console”—the change of sections along the branch provides constant stress level and near uniform dispensation of their without stress concentrators. Static simulation of the tree loading is provided both in the linear formulation and in the geometrically nonlinear one. It is proved that in the trunk-branch junction area the stresses are twice lower than the branch itself, and it is not the place for fracture. For the given wind pressure, the work stress in the branch has exceeded twice the allowable level under bending with some torsion. In such construction (of the tree), the breakage could happen even in the perfect branch condition due to her severe overloading.

Peryferyjny charakter to jedna z najważniejszych cech Polski Wschodniej, a sam region często identyfikuje się poprzez rozmaite negatywne zjawiska na płaszczyźnie społeczno--ekonomicznej. Duży wpływ na tę sytuację mają procesy ludnościowe, w tym problem wyludniania się, który dotyczy znacznej części obszarów wiejskich makroregionu. Celem niniejszej pracy jest analiza wpływu zmian demograficznych zachodzących na wiejskich obszarach przygranicznych Polski Wschodniej w latach 2002–2015 na wybrane obszary życia społeczno-ekonomicznego, a także próba określenia skali zmian i ich konsekwencji w ujęciu przestrzennym w sferze edukacji, przedsiębiorczości, budownictwa i mieszkalnictwa oraz finansów publicznych.

Demographic problem areas are perceived as one of the most important types of problem areas and require special research interest. Problem areas conditioned by population factor most often refer to rural areas. Presented article aims to identify and delimit rural demographic problem areas in Poland. The study covered rural areas distinguished on the basis of the classification of the European Commission DEGURBA The analysis enabled to identify depopulation areas, areas with disrupted population reproduction (ie areas of permanent natural decline), areas of permanent outflow of population, areas with impaired population structure by age and areas with disrupted population structure by sex in the group of people of marriage age (20-34 years). To indicate clusters of communes characterised by the presence of the unfavourable demographic phenomena and processes (rural demographic problem areas) the measure of local spatial autocorrelation (Anselin Local Moran's I) was applied. The application value resulting from the research may be the improvement of the effectiveness of public intervention carried out as part of the development policy.

Ethnic changes in Abkhazia (2nd half of the 19th century– beginning of the 21st century) Main aim of the paper is to analyse ethnic changes that took place in Abkhazia from the 60s of the 19th century to the present. The paper discusses the changes in ethnic structure of Abkhazia caused by the forced exodus of the Abkhazians to the Ottoman Empire (muhajirstvo), the process of multinational settlement in Abkhazia from the late 19th century to the 1990s, the Georgian-Abkhazian war of 1992-1993 and the national policy of de facto Abkhazia led in the post-war period in the terms of the absence of international recognition. Przemiany narodowościowe w Abchazji od II połowy XIX do początku XXI wieku Celem artykułu jest analiza przemian narodowościowych, jakie zaszły w Abchazji począwszy od lat 60. XIX wieku do chwili obecnej. W pracy omówiono zmiany w strukturze etnicznej w Abchazji warunkowane przymusowym eksodusem Abchazów do Imperium Osmańskiego (muchadżyrstwo), procesem wielonarodowościowego osadnictwa na te- renie Abchazji od końca XIX wieku do lat 90. XX wieku, wojną gruzińsko-abchaską z lat 1992-1993 oraz polityką narodowościową de facto Abchazji prowadzoną w okresie powojennym w warunkach braku uznania międzynarodowego.

The details of making technology of porous permeable material with use of wire are allowed to carry out the analytical research of structure and structural characteristics of wire winding body. Its permit for prognostication the final proper-ties of material, that is produced by the following deformation treatment (diameter reduction). Due to the regular orga-nized arrangement of wire, the coil of winding body is considered as a multispan continuous beam, but a contact of coils – as interaction of two cylinders. Possibility of exactly calculation of the contacts between coils is allowed to go over the single fragment displacements into deformation of whole winding body. During research of deformation processes in regards of winding body geometry and used wire mechanical properties, the structural characteristics of porous permea-ble wire material are expected. The optimal number of winding layers, eliminating the distortion of organized final struc-ture, is established. The material pressure–compactness relation is obtained in order to control the technological condi-tions of winding and drafting for guarantee the product required properties.

Large crankshafts are highly susceptible to flexural deformation that causes them to undergo elastic deformation as they revolve, resulting in incorrect geometric measurements. Additional structural elements (counterweights) are used to stabilize the forces at the supports that fix the shaft during measurements. This article describes the use of temporary counterweights during measurements and presents the specifications of the measurement system and method. The effect of the proposed solution on the elastic deflection of a shaft was simulated with FEA, which showed that the solution provides constant reaction forces and ensures nearly zero deflection at the supported main journals of a shaft during its rotation (during its geometry measurement). The article also presents an example of a design solution for a single counterweight.

Problems of Economic Development of the Unrecognised State – the Case of Abkhazia Since its inception as a result of the victorious war with Georgia, the de facto independent Abkhazia has been struggling with a deep economic crisis characterised by war damage, economic blockade and the lack of international recognition. The aim of this paper is to analyse the main problems and challenges of unrecognised states in the field of economic development on the example of the Republic of Abkhazia. The article summarises the economic consequences of the Georgian-Abkhazian conflict, characterises the economic development of Abkhazia in the post-war period and analyses the effects of the economic blockade as well as the economic effects of the support of the external patron (the Russian Federation).

This article aims to evaluate the level of tourism potential for the communities located in the eastern border region of the Lubelskie Voivodeship in Poland. The analysis was based on a three-factor model consisting of separate interrelated components of tourism potential i.e. tourist attractiveness, tourist function and tourist traffic. Using a multidimensional comparative analysis, a Tourist Attractiveness Index, Tourist Function Index and Tourist Traffic Index were composed. This enabled to identify the territorial units for which rural tourism can become a real factor stimulating socio-economic development. It appears that rural tourism can be perceived as a chance for improving the local economy for the areas located in the northern part of the borderland, whereas for communities situated in the southern part, it is not a significant issue.

This paper presents a review, based on the published literature and on the authors’ own research, of the current state of the art of fiber-optic capillary sensors and related instrumentation as well as their applications, with special emphasis on point-of-care chemical and biochemical sensors, systematizing the various types of sensors from the point of view of the principles of their construction and operation. Unlike classical fiber-optic sensors which rely on changes in light propagation inside the fiber as affected by outside conditions, optical capillary sensors rely on changes of light transmission in capillaries filled with the analyzed liquid, which opens the possibility of interesting new applications, while raising specific issues relating to the construction, materials and instrumentation of those sensors.

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The radiation damage caused by low energy r.f. plasmas has not been, to our knowledge, studied so far in the case of symmetric planar plasma reactors that are usually used for PECVD processes. The reason is that, unlike non-symmetrical RIE reactors, such geometry prevents, basically, high-energy ion bombardment of the substrate. In this work, we present the results of experiments in which we have studied the influence of plasma processing on the state of silicon surface. Very low temperature plasma oxidation has been used as a test of silicon surface condition. The obtained layers were then carefully measured by spectroscopic ellipsometry, allowing not only the thickness to be determined accurately, but also the layer composition to be evaluated. Different plasma types, namely N2, NH3 and Ar, were used in the first stage of the experiment, allowing oxidation behaviour caused by the exposure to those plasma types to be compared in terms of relative differences. It has been clearly proved that even though the PECVD system is believed to be relatively safe in terms of radiation damage, in the case of very thin layer processing (e.g., ultra-thin oxynitride layers) the effects of radiation damage may considerably affect the kinetics of the process and the properties of the formed layers.

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The paper briefly presents the history of microelectronics and the limitations of its further progress, as well as possible solutions. The discussion includes the consequences of the reduction of gate-stack capacitance and difficulties associated with supply-voltage scaling, minimization of parasitic resistance, increased channel doping and small size. Novel device architectures (e.g. SON, double-gate transistor) and the advantages of silicon-germanium are considered, too.

An important element in microelectronics is the comparison of the modelling and measurements results of the real semiconductor devices. Our paper describes the final results of numerical simulation of a micromechanical process sequence of the atomic force microscopy (AFM) sensors. They were obtained using the virtual wafer fab (VWF) software, which is used in the Institute of Electron Technology (IET). The technology mentioned above is used for fabrication of the AFM cantilevers, which has been designed for measurement and characterization of the surface roughness, the texturing, the grain size and the hardness. The simulation are very useful in manufacturing other microcantilever sensors.

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A new method for the fabrication of field emis- sion arrays (FEA) based on bulk/surface silicon micromachin- ing and diamond-like-carbon (DLC) coating was developed. A matrix of self-aligned electron field emitters is formed in sil- icon by mean anisotropic etching in alkali solution of the front silicon film through micro holes opened in silicon oxide layer. The field emission of the fabricated emitter tips is enhanced by a diamond-like-carbon film formed by chemical vapor de- position on the microtips. Back side contacts are formed by metal patterning. Detailed Raman, Auger and TEM investi- gations of the deposited DLC films (nanocrystalline diamond smaller than 10 nm) will be presented. In this paper we dis- cuss the problems related to the development of field emission arrays technology. We also demonstrate examples of devices fabricated according to those technologies.

A steady-state model of partially-depleted (PD) SOI MOSFETs I-V characteristics in subthreshold range is presented. Phenomena, which must be accounted for in cur- rent continuity equation, which is a key equation of the PD SOI MOSFETs model are summarized. A model of diffusion- based conduction in a weakly-inverted channel is described. This model takes into account channel length modulation, drift of carriers in the

SiGe-base HBTs with Gaussian doping distribution are modeled including the effect of the drift field and variable Ge concentration in the base on the diffusion coefficient. Two different Ge distributions in the base are considered: a triangular one and a box one the patterned substrates suffered from a high loading effect demanding an accurate calibration.

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A non-quasi-static model of partially-depleted SOI MOSFETs is presented. Phenomena, which are particularly responsible for dependence of device admittances on frequency are briefly described. Several C-V characteristics of the SOI MOSFET calculated for a wide range of frequencies, preliminary results of numerical analysis and of measurements and brief analysis of the results are presented. Methods of model improvement are proposed

SOI fabrication process was characterized using electrical and TEM methods. The investigated SOI structures included partially and fully depleted capacitors, gated diodes and transistors fabricated on SIMOX substrates. From C-V and I-V measurements of gated diodes, the following parameters of partially depleted structures were determined: doping concentration in both n- and p-type regions, average carrier generation lifetimes in the region under the gate and generation velocity at top and bottom surfaces of the active layer. Structures with short lifetime were studied using a transmission electron microscope. TEM studies indicate that the quality of the active layer in the investigated structures is good. Moreover, these studies were used to verify the thicknesses determined by means of electrical characterization methods.