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Designing an anatomical structure for a surgical procedure is not a simple task. It is especially true of the craniofacial area, which consists of bone tissues with very complex geometry. CAD modelers need appropriate knowledge and skills in medicine and technical sciences to fully use the currently available tools in related processes with the reconstruction of the craniofacial areas. The presented preliminary studies are based on four patients treated at the Department of Maxillofacial Surgery. The segmentation process of the mandible model was performed in the ITK SNAP software. The process of generating surface body models was performed in the Auto Surfacing module in Geomagic software using two different methods: organic and mechanical. Then compare both methods for the accuracy of generating a CAD model of the mandible based on a triangle mesh structure in the Focus Inspection and the GOM Inspect software.

Celem referatu jest ukazanie problemu religijno-politycznego ostatnich dziesięcioleci istnienia wspólnot chrześcijańskich w regionie Hakkari południowo-wschodniej Turcji przed ich totalną zagładą. Źródłem opracowania jest raport rosyjskiego generała Ryszarda Termena (1870–1937), który w latach 1905–1908 był wicekonsulem w wilajecie Wan. Znaczną część raportu stanowią opisy działalności misjonarzy rosyjskich (reprezentujących Kościół prawosławny), francuskich (Kościół katolicki), angielskich (Kościół anglikański) i amerykańskich (Kościoły protestanckie) wśród chrześcijańskiej ludności asyryjskiej regionu Hakkari. Termen wskazuje, że Asyryjczycy należący do Kościoła Wschodu („niestoriańskiego”) pomimo bardzo silnego przywiązania do swojej wiary i tradycji, chętnie zmieniali przynależność denominacyjną, kiedy widzieli nadzieję wsparcia politycznego. Po części zjawisko to było wynikiem politycznej natury islamu, który jako dominująca religia Turcji Osmańskiej nadawał chrześcijanom status obywateli drugiej kategorii. Wskutek dyskryminacji chrześcijan, korupcji urzędników i bezkarności band muzułmańskich Kurdów, Asyryjczycy w stanie skrajnej rozpaczy gotowi byli do masowej emigracji lub do powstania zbrojnego w sojuszu z dowolnym państwem prowadzącym wojnę przeciwko Turcji. Każda niemuzułmańska władza polityczna jawiła się im jako korzystna, o czym dobitnie świadczą niezwykle pozytywne wrażenia Asyryjczyków wyjeżdżających zarobkowo do Rosji. Innym ważnym elementem zmiany denominacji w celach politycznych było to, że Asyryjczycy uważali chrześcijaństwo za jednolitą religię, przejawiającą się w różnych formach. Za cenę krwi opierali się przyjęciu islamu, ale po kilka razy przechodzili na prawosławie, anglikanizm lub katolicyzm, kiedy widzieli płynące z tego korzyści materialne i polityczne. I w końcu najważniejszy chyba problem religijno-politycznego charakteru misji był związany z tym, że na Zachodzie Kościół już nie miał takiego wpływu na politykę rządów, jak na Wschodzie, i często obietnice misjonarzy – zarówno te wyartykułowane, jak i te domniemane przez Asyryjczyków – były bez pokrycia. Skończyło się to katastrofą chrześcijaństwa w Hakkari, gdyż Asyryjczycy ulegli wpierw rozbiciu jedności religijnej, a potem zdradzeni przez polityczne władze Zachodu zostali zmasakrowani przez przeważające siły muzułmańskich Kurdów i Turków.

W artykule przedstawiono analizę perykopy zawierającej wołanie "Hosanna" w wersji Mt 21,9. Dla lepszego zrozumienia znaczenia tego słowa, które często wyjaśniane jest jako lityrgiczny okrzyk, omówiono szerszy kontekst niż ograniczający się zazwyczaj do Ps 118. W szczególności przeanalizowano kilka polskich wydań Biblii, a także starożytne tłumaczenia Septuaginta, Targum i Peszitta Starego i Nowego Testamentu. Przeanalizowano również liturgię żydowską nazywaną "Hoszanot" wykazując, że w modlitwach hebrajskie słowo "hosza na" jest używane w jego bezpośrednim znaczeniu. Ponadto, bazując na tym znaczeniu, odnotowano powiązanie wołania "Hosanna" z wersetami poprzedzającymi Ewangelii Mateusza, gdzie niewidomi wołali o zbawienie. Godnym odnotowania jest fakt, że niewidomi zostali uzdrowieni zarówno przed, jak i po analizowanym wydarzeniu. Ze względu na to, że kontekst wskazuje na misję prorocką Jezusa spełnioną w Świątyni, nieco uwagi poświęcono zagadnieniu proroctwa. Stwierdzono, że spełnienie wyroku Jesusa nad bezowocnym drzewem figowym zaznacza nieuniknione spełnienie proroctwa o zburzeniu Jerozolimy. Całościowy kontekst daje mocne podstawy do rozumienia tekstu w taki sposób, że Jezus podkreśla swoją tożsamość jako Boga zarówno słowami, jak i czynami, zaś spontaniczne wołanie tłumu "Hosanna" dostarcza kluczy do zrozumienia tego przesłania.

This paper presents a novel mass comparator designed for the purpose of measuring small weights of 2 mg and lower, with readability of 10 ng. The mass comparator was developed using new types of coil and actuator. The added protective ring decreased the average sorption-induced mass variation for the coil by 84%. The accuracy of the novel comparator was verified in terms of stability, Type An uncertainty, and repeatability. Compared to the device of the best available accuracy, the standard uncertainties of the novel-design comparator were approximately 70% narrower.

The development of environmentally friendly technologies, including additive technologies, contributes to the formation of sustainable production in city multifloor manufacturing clusters (CMFMCs). This paper discusses an approach to the implementation of energy-intensive technological processes in such clusters using examples of the manufacturing of ceramic and metal–ceramic products. The manufacturing of ceramic and metal–ceramic products in high-temperature furnaces is associated with an increased electricity consumption. The use of modern ceramic micro- and nanopowders makes it possible to switch to more energy-saving technologies by reducing the sintering temperature and shortening the technological cycle. This requires the use of additional activating and inhibiting additives in the initial powder mixtures to obtain products with the necessary physical and mechanical properties. The purpose of this paper is to present a model and indicators to assess the energy efficiency of the choice of sintering technology of foam ceramic filters for smart sustainable production management within CMFMCs. The use of the proposed indicators for assessing the energy efficiency of sintering foam ceramic filters makes it possible to improve the technological process and reduce the completion time of its thermal cycle by 19%, and reduce the maximum heating temperature by 20% to 1350 °C. The adoption of a different oxide technological alternative and the use of the proposed model and indicators to assess the energy efficiency of the sintering technology of foam ceramic filters allows to choose less energy-intensive equipment and save up to 40% in electricity. The proposed model to assess the energy efficiency of the sintering technology of foam ceramic filters can be used to control their production under the power consumption limitations within the CMFMCs.

From the perspective of today’s scientific methodology, the Bible does not count as a scientific source, at least as far as the natural sciences are concerned. However, for many centuries biblical texts have inspired reflections — including those of a philosophical kind — on the beginning of the existence of all things. The treatise Midrash Rabbah, with its commentary on the Book of Genesis, is an example of such reflections. In spite of the fact that rabbinic interpretation focuses on practical aspects of the Mosaic Law, it often raises philosophical and existential questions, especially in the context of those discussions that involve the gentile philosophers referred to in the treatise. The analysis undertaken here seeks to highlight those rabbinic reflections that appear reasonable even from the perspective of modern science aimed at describing the world and its origin — even though the rabbis were not themselves engaged in any form of the natural sciences and based their reflections exclusively on biblical texts.

Artykuł zawiera przegląd i analizę tekstów biblijnych związanych z sądem od upadku pierwszych ludzi poprzez czasy Mojżesza i proroków aż do Chrystusa i sądu ostatecznego. Analiza wykazuje, że sąd Boży opisywany na kartach Pisma św. znacznie różni się od popularnych o nim wyobrażeń. Niektórzy badacze postrzegają sąd ostateczny jako przekleństwo kontrastujące z wiecznym błogosławieństwem czy też z eschatologiczną mesjańską ucztą, tymczasem wiele biblijnych tekstów podkreśla pozytywny charakter sądu Bożego. Bóg jest ukazywany w Biblii jako sprawiedliwy sędzia, dbający o prawa najsłabszych, do którego zwraca się każdy pokrzywdzony. Kara, wynikająca ze sprawiedliwego osądu, jest ostatecznym zniszczeniem tego, co już zostało zburzone przez złoczyńców. W tym kontekście sąd ostateczny jawi się jako wyczekiwane pozytywne doświadczenie.

Dynamic properties of the air gauges performing in-process measurement are of the great importance because of dynamic error affecting the measurement results. The paper presents the analysis of the air gauges dynamics and some practical recommendation. The investigations proved the dependence of the time constants on the actually measured back-pressure. In practical solutions of in-process control, the air gauge must work in conditions of falling back-pressure since with the material removal dimensions of the machined workpiece go down. Thus, in the area of the smallest values of back-pressure within the measuring range, the time constant value is the largest. Worsening of the air gauge dynamic properties at the end stage of the machining must be considered when the dynamic characteristics of the projected air gauge are calculated.

In the paper, impact of the precursor decomposition conditions on the morphological and structural characteristics of TiO2 particles was discussed. The novelty and significance of the researches lay in the ability to control morphological features of the synthesized powder particles so that enhanced properties of the sintered ceramics can be obtained. The research program covered thermal decomposition of titanium nitrate, titanium oxyfluoride and titanium oxysulphate at different temperatures, with and without organic additive. Obtained titanium dioxide powder underwent analysis, namely, its phase composition, particle shape and dimensions were measured using X-ray and IR-spectra, as well as scanning electron microscopy. Activity of the obtained particles during sintering process was analyzed using dilatometer and microhardness measurement after sintering. It was found that spherical TiO2 nanoparticles of anatase and rutile phases can be obtained from decomposition of titanium nitrate at 700 °C. Thermal decomposition of other precursors, titanium oxyfluoride and oxysulfate, synthesized only anatase phase with particles of 200 and even 300 nm. Obtained spherical particles were smaller when temperature of decomposition was lower or the activator OP9 was added. However, lower decomposition temperature and additive had negative effect on sintering activity of the obtained particles, decreasing the microhardness of sintered specimens.

In this paper, research results are presented and discussed on the efficient use of additive manufacturing (AM) machine workspace with a specific focus on the features of part construction and deco...

Wooden or wood-plastic composite surfaces are often valued for their aesthetic appearance and the quality of the surface. Independent from the technology, the surface features may be assessed using typical roughness parameters. In this paper, a pneumatic non-contact method is proposed. Despite certain limitations in surface characteristics measurement, air gauges proved to be a good tool for wooden surfaces, much cheaper than the laser profilometers. In the current research, a novel non-contact air gauge was combined with a slider to eliminate the influence of the asperities of higher order (waviness) and to protect the wooden surface from being damaged by the measuring nozzle. The measurement signal was used to control a follower that kept constant distance between the surface and the nozzle edge. The measuring speed was set at 0.8 mm/s, and the back-pressure was measured with accuracy of 0.01 kPa with real time acquisition. A series of measurements was taken, and the results were compared with the ones obtained from Perthen S8P profilometer (contact measurement) and WYKO NT 1100 interferometer microscope.

The aim of the current paper is to investigate a small airplane model propeller of class F2D according to requirements of Fédération Aéronautique Internationale (FAI, or World Air Sports Federation). In some cases, practical tests show that F2D models with flexible propellers produce specific extra noise and increase flight speed in comparison with “rigid” propellers. Therefore, the following hypothesis could be proposed: flexible characteristics of the increased noise are related to the resonant eigenfrequencies of the propeller. The operating range of the F2D class propeller (28,000-35,000 rpm) is close to or equal to the eigenfrequency resonance. The current investigation addresses dynamic/flexible vibrations of elastic propeller during engine run and researches dynamic parameters of the propeller as well as the contribution of these parameters to the model flight characteristics. To resolve this type of a problem, a stand, which allows completing a physical investigation of flexible propeller vibration modes and dynamic characteristics was created.

Negative Poisson’s ratio materials (called auxetics) reshape our centuries-long understanding of the elastic properties of materials. Their vast set of potential applications drives us to search for auxetic properties in real systems and to create new materials with those properties. One of the ways to achieve the latter is to modify the elastic properties of existing materials. Studying the impact of inclusions in a crystalline lattice on macroscopic elastic properties is one of such possibilities. This article presents computer studies of elastic properties of f.c.c. hard sphere crystals with structural modifications. The studies were performed with numerical methods, using Monte Carlo simulations. Inclusions take the form of periodic arrays of nanochannels filled by hard spheres of another diameter. The resulting system is made up of two types of particles that differ in size. Two different layouts of mutually orthogonal nanochannels are considered. It is shown that with careful choice of inclusions, not only can one impact elastic properties by eliminating auxetic properties while maintaining the effective cubic symmetry, but also one can control the anisotropy of the cubic system.

W artykule przeanalizowano zagadnienie gniewu Baranka pojawiającego się w opisie wizji złamania szóstej pieczęci w Księdze Objawienia (Ap 6,17). Gniew Baranka jest czymś niezwykłym i paradoksalnym sam w sobie, gdyż baranek nie jest zwierzęciem kojarzącym się z gniewem. Dlatego też w badaniach zazwyczaj więcej uwagi poświęca się zwycięstwu Baranka i Jego chwale, a także roli, jaką odegrał w zbawieniu ludzi, i Jego uczcie weselnej. Niniejsze studium obejmuje kontekst złamania szóstej pieczęci oraz następujących po nim plag i nieszczęść z odniesieniami do literatury rabinicznej i tekstów innych ksiąg biblijnych. Osobno omówiono poruszenie kosmosu oraz przerażenie ludzi spowodowane gniewem baranka. Dokonano też porównania gniewu ludzkiego z gniewem Bożym.

This article is devoted to nanoscale composite materials based on Cr2O3 obtained by the activated electric fields sintering procedure. In the paper, exploitative properties of the sintered system of Cr2O3 – AlN nanocomposite was examined. Mechanical properties of the material were examined, especially from the perspective of its performance in the cutting tools. In particular, its wear was tested at different cutting speeds, as well as for intermittent hard cutting, and the results were compared with other materials available in the market. Compared to other cutting tools of the same class, Bichromit-R performed the same lifetime for 3-5 times higher cutting speeds, or up to 45% longer lifetime for the same cutting speed. The results lead to the conclusion that composite nanostructure improves substantially exploitation characteristics of the cutting tools.

Fabrication of alumina–tungsten carbide nanocomposite was investigated. Characteristics of the densification and sintering were analyzed considering both the nano-size particle starting powders and the processing stages. Different heating rates were generated during densification and consolidation with a maximal load was applied only after a temperature of 1000 °C was reached. Due to the varying dominance of different physical processes affecting the grains, appropriate heating rates and pressure at different stages ensured that a structure with submicron grains was obtained. With directly applied alternating current, it was found that the proportion Al2O3 (50 wt.%)–WC provided the highest fracture toughness, and a sintering temperature above 1600 °C was found to be disadvantageous. High heating rates and a short sintering time enabled the process to be completed in 12 min, saving energy and time.

In this paper, the results of an investigation on the application of air gauges in the measurement of out-of-roundness parameters are presented. The principle of the measuring system is explained, in particular the novel design of the floating gauge head. An algorithm for fully automated measurement and data processing is described. The results from a series of initial measurements provided the data for further simulations, which revealed possible sources of errors. The simulations helped to evaluate the influence of some of the parameters on the final measurement results. After various accuracy tests, the method accuracy (MA) parameter was calculated in relation to the dedicated reference form tester. The result MA = 9.29% was judged to be highly satisfactory considering the short measurement time and non-contact method.

In the paper, the process of hot vacuum pressing of Al 2 O 3 -based components of gas turbines is analyzed. Computer simulation of the temperature field in the installation of powdered billet of Al 2 O 3 -SiC was preformed using the finite element method. The model took into account the temperature dependence of the thermophysical properties of the materials of the installation elements and billet, as well as the thermal and electrical resistances in the contact area. Concordance between the obtained results of calculations and laboratory measurements of temperature proved the reliability of the model. The results of computer experiments show that by selecting the materials of the installation elements, it is possible to obtain homogeneous temperature field in the sample at the final stage of the sintering process. This way the energy consumption of the entire sintering process can be significantly reduce, and higher structural homogeneity of bulk material can be reached.

The paper presents results of investigations on the binderless nanostructured tungsten carbide (WC) cutting tools fabrication and performance. The scientific novelty includes the description of some regularities of the powder consolidation under electric current and the subsequent possibility to utilize them for practical use in the fabrication of cutting tools. The sintering process of WC nanopowder was performed with the electroconsolidation method, which is a modification of spark plasma sintering (SPS). Its advantages include low temperatures and short sintering time which allows retaining nanosize grains of ca. 70 nm, close to the original particle size of the starting powder. In respect to the application of the cutting tools, pure WC nanostructure resulted in a smaller cutting edge radius providing a higher quality of TiC/Fe machined surface. In the range of cutting speeds, vc = 15–40 m/min the durability of the inserts was 75% of that achieved by cubic boron nitride ones, and more than two times better than that of WC-Co cutting tools. In additional tests of machining 13CrMo4 material at an elevated cutting speed of vc = 100 m/min, binderless nWC inserts worked almost three times longer than WC-Co composites.

The paper provides novel basis for composite material Al2O3-SiC as an instrumental material. The advantage of this composite material in comparison with the material having additives made out of SiC fibers is analyzed and justified. The microstructures of composites under various modes of electric sintering (electric consolidation) are considered. Some mechanical properties of the composite materials obtained by electric sintering, their phase compositions are determined, and comparative assessment of the properties is given. Some advantageous mechanical properties of obtained Al2O3-SiC composites were pointed out, obtained with less energy consumption than other reported composites.

The paper presents the results of investigations on the tribological properties of cutting tools after ion implantation. The research focused on the inserts made out of nitride ceramics IS9 (Si3N4 with additives) and combined ceramics IN22 (Al2O3 + TiCN) available on the market. The inserts rake surfaces were covered with yttrium and rhenium coatings by means of ion implantation with different dozes. Both unimplanted and coated surfaces underwent tribological tests of the block-on ring type. The experiments demonstrated that, in general, ion implantation with rhenium (Re+) and yttrium (Y+) provided a decrease in surface friction forces. In the case of IN22 ceramics, both rhenium and yttrium ions improved wear resistance of cutting inserts. On the other hand, Re+ implantation provided the best wear resistance of the IS9 ceramics.

The paper describes the tests carried out for the extraction of radionuclides 90Sr, 137Cs and 60Cо by manganese oxyhydroxide in order to compare the sorption properties of the respective particles with Sr(II), Cо(II), Cе (III), Eu (III) ions. It was found that the recovery efficiency and the sorption capacity with respect to metal ions decrease in the MnOOH → MnO2 → Mn3O4 series. The tests proved that the extraction of the radionuclides from tap water by MnOOH particles was 53.7%, 83.5% and 93.1%, respectively.

Artykuł rzuca pewne światło na zagadnienie związane z klasztorami, które w ciągu prawie dwóch tysięcy lat pełniły funkcje ośrodków edukacyjnych w Kościołach na Wschodzie. Oprócz światowej sławy szkół w Nisibis, Edessie czy Antiochii, są informacje o 125 klasztorach, z którymi związani są pisarze syriaccy. Większość z nich już nie istnieje. Źródła historyczne i archeologiczne dostarczają danych o znacznie większej liczbie klasztorów działających na terenie dzisiejszej Turcji, Syrii i Iraku. Jednak inwazja islamu znacznie ograniczyła rozwój nauki i edukacji w klasztorach, na które nałożono wysokie podatki. Nie wolno było już budować nowych klasztorów, a poszerzanie i remontowanie starych było znacznie utrudnione. W końcu masakry przeprowadzone przez Tamerlana zadały śmiertelny cios, po którym wschodnie Kościoły nie były w stanie powrócić do poprzedniego stanu, mimo że w XV w. miał miejsce wzrost liczby klasztorów. Do dziś zachowało się zaledwie kilkadziesiąt klasztorów, które są poważnie zagrożone. Dwa z nich ostatnio zrównano z ziemią.

In the paper, a novel technique for highly dispersed pyrochlore Y2Ti2O7 is proposed. The experimental results proved that the application of microwave irradiation at a certain stage of calcination allowed synthesizing of Y2Ti2O7 in much shorter time, which ensured substantial energy savings. An increase up to 98 wt.% in the content of the preferred phase with a pyrochlore-type structure Y2Ti2O7 was obtained after 25 h of yttrium and titanium oxides calcination at a relatively low temperature of 1150 °C, while the microwave-supported process took only 9 h and provided 99 wt.% of pyrochlore. The proposed technology is suitable for industrial applications, enabling the fabrication of large industrial amounts of pyrochlore without solvent chemistry and high-energy mills. It reduced the cost of both equipment and energy and made the process more environmentally friendly. The particle size and morphology did not change significantly; therefore, the microwave-assisted method can fully replace the traditional one., This article belongs to the Special Issue Advances in Materials Processing, This research was supported by Ministry of Education and Science of Ukraine, grant No. 0118U002026 “Physical Principles and Creation of Promising Composite Materials with Ultra- and Nanosized Oxides of New Generation for Heavy Duty” and co-funded from the ‘Excellent science’ program of the Polish Ministry of Science and Higher Education as a part of the contract No. DNK/SP/465641/2020 “The role of the agricultural engineering and environmental engineering in the sustainable agriculture development.”

In the paper, the issue of the supervision of belt tension and wear in industrial feeder is addressed. The designed system is based on strain gauges that are built into the roller and are subject to the belt pressure at each revolution. In order to assess the effectiveness of this system, calibration and uncertainty analysis was performed. As a result, it was demonstrated that the main source of uncertainty was the function of approximation, while the others were orders of magnitude smaller. The final function provided results with accuracy of ca. 10% of actually measured value, which was assumed to be a good result for this particular industrial application.

The paper is dedicated to the lifetime prolongation of the tools designed for deep-hole drilling. Among available methods, an ion implantation process was used to improve the durability of tungsten carbide (WC)-Co guide pads. Nitrogen fluencies of 3 &times, 1017 cm&minus, 2, 4 &times, 2 and 5 &times, 2 were applied, and scanning electron microscope (SEM) observations, energy dispersive spectroscopy (EDS) analyses, X-ray photoelectron spectroscopy (XPS) and Secondary Ion Mass Spectrometry (SIMS) measurements were performed for both nonimplanted and implanted tools. The durability tests of nonimplanted and the modified tools were performed in industrial conditions. The durability of implanted guide pads was above 2.5 times more than nonimplanted ones in the best case, presumably due to the presence of a carbon-rich layer and extremely hard tungsten nitrides. The achieved effect may be attributed to the dissociation of tungsten carbide phase and to the lubrication effect. The latter was due to the presence of pure carbon layer with a thickness of a few dozen nanometers. Notably, this layer was formed at a temperature of 200 &deg, C, much smaller than in previously reported research, which makes the findings even more valuable from economic and environmental perspectives.

In this study, the effect of the addition of silicon carbide to alumina ceramics commonly used in cutting tool applications is addressed. Performance of Al2O3&ndash, SiC composite cutting inserts during the machining of hardened steels and ductile iron was compared to the results obtained for a cutting tool made out of 99 wt.% Al2O3, Al2O3&ndash, TiC, Al2O3&ndash, TiC&ndash, ZrO2, and Al2O3&ndash, TiN. In almost all tests, the composite with silicon carbide demonstrated better wear resistance, longer tool lifetime, and the ability to cut at higher speeds. The enhanced properties of cutting tools with SiC can be attributed to the morphology and dimensions of the inclusions in the matrix as well as to the strength of the interphase boundaries, small porosity, and lack of high inner stresses in the volume.