Indirect Electro-Thermal Modelling of Semiconductor Diode Using Non-Linear Behavior of Volt-Ampere Characteristic

The aim of the proposed paper is the development of an electro-thermal model of semiconductor component using an indirect modelling approach. The approach is based on the integration of the component’s electrical properties considering non-linear behavior of a V-A characteristic. In this way, the identification of semiconductor material properties considering non-linear dependencies and semiconductor volume is provided. The main aim of the presented approach is simplification of the electro–thermal interaction within finite-element modelling of the semiconductor components. In this way, it is possible to omit more complex boundary definitions and the setting of the semiconductor-based physics. The proposed methodology is presented within the development of a simulation model based on a small high-frequency rectifying diode, taking into account its geometric dimensions and the internal arrangement of its structure. Simulation was performed as a transient analysis, while the results from the steady-state operation for various operational conditions were compared to experimental measurements. Comparison between simulation and experiments is within 5% of the relative error. The achieved results represent appropriate accuracy of model behavior compared to the real operation.

Restaurant service: from satisfying utilitarian and pragmatic to cultural and leisure needs

The purpose of the article is to analyze the main requirements for the organization and management of various types of restaurant facilities, taking into account the need to ensure the cultural and leisure needs of the population. Research methodology. The basis of the research is the general scientific interdisciplinary methodology, which is based on the fundamental provisions of management, cultural studies, design, and other sciences. Common scientific methods are used: analysis, synthesis, generalization, classification, etc. The scientific novelty of the obtained results is that the main tendencies of the reorientation of catering establishments, in particular in Ukraine, in the original centers of culture, with their functions of leisure centers and entertainment, which is reflected in the National Standard, are also revealed. Conclusions. Despite the importance and numerous variations of the communication and entertainment and visual and artistic component of the interior space of restaurant enterprises, the main function of their catering is the priority of their internal arrangement. In the XX - the beginning of the XXI century, several basic types of functional types of institutions have been formed, with their inherent features of creation, zoning, and arrangement in accordance with the interests of clients of certain strata of the population, which imposes specific requirements for their organization, in particular, taking into account the leisure-time orientation.

Phase Composition and Its Spatial Distribution in Antique Copper Coins: Neutron Tomography and Diffraction Studies

The chemical and elementary composition, internal arrangement, and spatial distribution of the components of ancient Greek copper coins were studied using XRF analysis, neutron diffraction and neutron tomography methods. The studied coins are interesting from a historical and cultural point of view, as they are “Charon’s obol’s”. These coins were discovered at the location of an ancient Greek settlement during archaeological excavations on the “Volna-1” necropolis in Krasnodar Region, Russian Federation. It was determined that the coins are mainly made of a bronze alloy, a tin content that falls in the range of 1.1(2)–7.9(3) wt.%. All coins are highly degraded; corrosion and patina areas occupy volumes from ~27 % to ~62 % of the original coin volumes. The neutron tomography method not only provided 3D data of the spatial distribution of the bronze alloy and the patina with corrosion contamination inside coin volumes, but also restored the minting pattern of several studied coins. Taking into account the obtained results, the origin and use of these coins in the light of historical and economic processes of the Bosporan Kingdom are discussed.

STRENGTH, DURABILITY AND MICROSTRUCTURE INVESTIGATIONS OF CONCRETE CONTAINING EMPTY PALM OIL FRUIT BRUNCH ASH (EPO-FBA)

Understanding of the internal arrangement of the constituents of structural concrete, at the microscopic level, and its strength behavior, as well as its ability to result in durable concrete, are necessary in order to enhance its innovative and sustainable application. This paper presents the results of investigation conducted to ascertain the strength characteristics, microstructure configuration and durability traits of concrete with its ordinary Portland cement (OPC) fraction replaced partially with empty palm oil fruit brunch ash (EPO-FBA). The compressive strength properties were assessed with 150 x 150 x 150 cube specimens while 100 x 100 x 100 cube specimens were used to assess the durability properties. An insight into the morphology and the microstructure of samples with EPO-FBA was obtained through Scanning Electron Microscopy (SEM). The results showed that EPO-FBA is a good supplementary cementing material up to 10% replacement level, however, the samples with EPO-FBA showed a significantly improved compressive strengths development and good durability characteristics at latter ages, at the replacement level beyond 10%.

Three-dimensional stromatolites from Maastrichtian–Danian Yacoraite Formation, Argentina: modelling and assessing hydrodynamic controls on growth patterns

Stromatolites are biogenic sedimentary structures formed by the interplay of biological (microbial composition) and environmental factors (local hydrodynamic conditions, clastic input and/or water chemistry). Well-preserved, three-dimensional (3D) fossil stromatolites are key to assessing the environmental factors controlling their growth and resulting morphology in space and time. Here, we report the detailed analysis of well-exposed, highly informative stromatolite build-ups from a single stratigraphic horizon within the Maastrichtian–Danian Yacoraite Formation (Argentina). This study focuses on the analysis of depositional processes driving intertidal to shallow subtidal stromatolites. Overall depositional architecture, external morphology and internal arrangement (mega, macro, meso and microstructures) of stromatolite build-ups were analysed and combined with 3D photogrammetric models, allowing us to decipher the links between stromatolite structure and tidal dynamics. Results suggest that external morphology and architecture of elongated and parallel clusters grew under the influence of run-off channels. The internal morphology exhibits columnar structures where the space between columns is interpreted as recharge or discharge channels. This work supports the theory that stromatolites can be used as a high-resolution tool in the assessment of water dynamics, and provides a new methodological approach and data for the dynamic reconstruction of intertidal stromatolite systems through the geological record.

First in situ 3D visualization of the human cardiac conduction system and its transformation associated with heart contour and inclination

Current advanced imaging modalities with applied tracing and processing techniques provide excellent visualization of almost all human internal structures in situ; however, the actual 3D internal arrangement of the human cardiac conduction system (CCS) is still unknown. This study is the first to document the successful 3D visualization of the CCS from the sinus node to the bundle branches within the human body, based on our specialized physical micro-dissection and its CT imaging. The 3D CCS transformation by cardiac inclination changes from the standing to the lying position is also provided. Both actual dissection and its CT image-based simulation identified that when the cardiac inclination changed from standing to lying, the sinus node shifted from the dorso-superior to the right outer position and the atrioventricular conduction axis changed from a vertical to a leftward horizontal position. In situ localization of the human CCS provides accurate anatomical localization with morphometric data, and it indicates the useful correlation between heart inclination and CCS rotation axes for predicting the variable and invisible human CCS in the living body. Advances in future imaging modalities and methodology are essential for further accurate in situ 3D CCS visualization.

The Educational Aspect of School Libraries’ Design and the Students' Territorial Behavior

In a study combining qualitative (observation and interviews) and quantitative (questionnaires) methods, the researchers examined the territorial behavior of students and the implications of the internal arrangement of the library space for the students. The territorial behavior observed in the libraries could be seen in where the students decided to sit and how they used library furniture (including chairs, armchairs, computers and the librarian station). Most of the students preferred sitting in a central area in the library. However, for the most part, students chose to sit in places that enabled them to maintain territorial control. While many students sat in groups for both social and study purposes, some of them (particularly the older students) had a need to protect against intrusion into their personal space. This was achieved by sitting at the tables with their backs to the entrance, by body language and, at times, even by using personal belongings to demarcate personal territory. Library planners and librarians must be aware of these “conflicting” needs in order to adapt the design to the behaviors typical of the groups that use the library.

The AD 79 Vesuvius eruption: stratigraphy, lithofacies variations and impact of the pyroclastic current deposits within the archaeological sites of Pompeii and Stabiae (southern Italy)

<p>Plinian eruptions are powerful explosive volcanic events that impact large areas with cubic kilometers of magma emplaced as pyroclastic material accumulated in thick blankets around the volcanic vents. The violence of the emplacement mechanism (i.e., fallout or pyroclastic density currents, PDC) and the sudden burial of the landscape, make these types of eruptions extremely dangerous. Aiming to fully understand these phenomena, an accurate reconstruction of the physical behaviour and the historical record of a volcano is critical as starting point for the assessment of volcanic hazard. In this scenario an excellent case is the worldwide-known Plinian AD 79 Vesuvius eruption, which destroyed Roman towns with large effects preserved in different sites around the volcano. This study reports the results of a collaboration between the Archaeological Park of Pompeii and the University of Napoli Federico II to document the stratigraphic sequence and the type and extent of damage and victims buried under meters of pyroclastic material within the Pompeii and Stabiae archaeological sites. A systematic survey of well exposed outcrops along the recent excavations front allowed us to study in detail the facies variations of the different PDC stratigraphic units and how their distribution is affected even by urban structures. At Pompeii, the stratified ash PDC succession ranges in thickness from few tens of centimetres to two metres and shows considerable vertical and lateral variations in its sedimentological features. The layer associated with the most destructive impact on the Roman buildings shows down-current variation in thickness (0 to 330 cm) and texture. Where it is less than 30 cm thick, the deposit is fine-grained and thinly stratified, with few rounded pumice clasts scattered inside the matrix. Where it thickens, the lower part is rich in coarse pumice lapilli and locally shows well-developed stratifications, while the upper part shows an internal arrangement of alternating layers of fine and coarse ash, forming progressive bedforms. Upwards, the sequence is made up of a succession of plane-parallel ash layers with rare pumice lapilli clasts and diffuse accretionary lapilli. This ash sequence is interstratified with four well-sorted, thin lithic-rich layers that exhibit mantling structures of fall deposits. All PDC layers, except the lowermost, are dispersed across the entire Pompeii area, although some are locally missing as a result of the erosive action of the following PDC. At Stabiae, the ash PDC sequence is 83 cm thick. In few rooms of the Roman villa the ash deposits thicken up to 150 cm. Most of the ash layers identified at Pompeii are recognized also at Stabiae. In the upper part of the sequence a new PDC layer, never reported at Pompeii, is here documented for the first time. Damages are documented inside the more destructive ash layer and even in the upper ash layers, providing new insights about the risk assessment in distal areas.</p>

URBAN PLANNING ARCHITECTURE

Statement of the problem. New challenges of our time and the dynamics of socio-political and socio-economic factors in the development of Russia significantly affect the methodology of urban planning. The deteriorating environmental situation in many cities encourages a new approach to understanding and developing new principles of city life that regulate the biosphere compatibility of cities and the development of human capital as the main criteria for the effectiveness of territorial planning, construction and operation of urban facilities. Results. The article deals with a fundamentally new approach-urban planning, which should be understood as a system of fundamental provisions on life in the territories of cities and settlements and the principles of their spatial development and settlement. In practical terms, urban planning is an activity for the internal arrangement of the city's living environment, creating favorable conditions for the life of all categories and strata of the population without exception. The fundamental differences between the concept of urban development and urban planning are related to the need to understand the unity of the city and Nature, the symbiotic "embedding" of the city in the Biosphere. The Central element of the concept of urban development is the person, the conditions for its development in the urban environment.Conclusion. As part of the research, the practice of urban planning allows solving the problems of innovative development of the urban economy and increasing human potential, and in the long term -- transforming cities into biosphere-compatible and developing people as an alternative condition forthe survival of humanity and a priority for its development as an intellectual community.