Wall paintings in the Church of St. George in Kostoľany pod Tribečom discovered 60 years ago, belong to the oldest early medieval frescoes preserved on the contemporary territory of Slovakia dated ...from the middle of 11th until 12th centuries. Just Josef Krása and Ján Bakoš interpreted the lower part of frescoes in the context of Christology iconography primarily devoted to the Nativity of Jesus Christ. Only two registers of frescoes situated next to the triumphal arc of presbytery have not been correctly interpreted yet. This study is devoted to analysing especially those parts of the frescoes which have to be associated with Donor iconography. On the nave's south wall is a profane scene with the depicted prince of Poznan family with his two sons. The church founders, accompanied by St. George, offer a model of the church to Jesus Christ. On the north part of the nave, there is a religious scene depicting probably an anonymous abbot of Zobor Monastery accompanied by St. Adalbert praying before sitting Holy Mother with child Jesus on her knees. This scene was created on the occasion of the donation of a church by the Poznan nobleman family to St. Hippolytus Monastery. The author of the study puts the origin of frescoes into the context of historical events nearly linked with activities of Benedictine monks who came from the monastery of St. Boniface and Alexis on Aventine Hill in Rome, arrived in Central Europe together with St. Adalbert in 992. Frescoes could be made after St. Adalbert's martyr death and before his canonisation in 999.
Ikonografické pramene k odievaniu v období Veľkomoravskej ríše Vančo, Martin
Acta historica neosoliensia : odborný časopis Katedry histórie Fakulty humanitných vied Univerzity Mateja Bela v Banskej Bystrici,
2017, Letnik:
2, Številka:
20
Journal Article
Odprti dostop
The subject matter of this paper is an analyse of Moravian Slavs clothing according to the figural motifs depicted on the Great Moravian monuments of art craft and its interpretation on the basis of ...written documents and knowledge from philology field of study. The Great Moravian rulers were probably dressed according to previous heritage of Avar Khaganate characterised by nomadic riding clothing, e.g. short coat – “župan” tied up at the waist with a strap and wide trousers and high boots. The other type of the Great Moravian man’s clothing had been determined by political situation from the end of 8th century when Carolingian Empire was spread out in the eastern part of Europe. Carolingian fashion was based on a long sleeve tunica tied up at the waist by strap with a mantle and pantyhose with calf-straps. Monks and priests were dressed according to late Roman tradition what can be seen on figural motifs with long-sleeved tunica − dalmatic with outermost liturgical vestment chausuble − casula. Traditional old Slavic dress consists of trousers, shirt and mantle, described in written documents was not identified on any Great Moravian archaeological findings. As far as woman’s clothing is concerned we have no visual records about this fashion.
Stručna javnost odnedavna posvećuje znatnu pozornost pozlaćenim bakrenim pločicama s figuralnim dekorom i natpisima iz velikomoravskoga gradišta Bojna I – Valy, koje se smatraju jednim od najstarijih ...dokaza kršćanstva na području Velike Moravske. Pločice su kupljene od privatnog skupljača i smještene u Ponitrianski muzej, a 2003. nalazište je podvrgnuto reviziji Karola Piete. Prema K. Pieti i A. Ruttkayu šest pločica s motivima oranta pripadalo je izvorno prijenosnom oltaru koji se veže uz franačku misiju s početka 9. stoljeća. S ikonografskoga gledišta, na pločicama iz Bojne nisu prikazani oranti, nego anđeli iz raznih anđeoskih korova: Anđeo Velikog savjeta na br. 1, kerubin na br. 6, serafin na br. 5, arhanđeli na br. 2, anđeli na br. 3 i 4. Takva je hijerarhija anđela prvi put predložena u radu Pseudo-Dinizija Areopagita, neoplatonističkog teologa iz 5.-6. stoljeća, De caelesti Hierarchia (poglavlje 4.). Tekst se čuvao u Bizantu i tek se godine 827. pojavljuje na Zapadu kao dar cara Mihajla II. Mucavca (820.-829.) franačkom vladaru Luju Pobožnom. Na latinski su ga preveli franački teolozi i filozofi opat Hilduin i Johannes Scottus Eriugena. Stoga pločice iz Bojne nisu mogle nastati pod franačkim teološkim utjecajem, a nema ni potrebe da ih se veže uz prijenosni oltar, već ih treba vezati uz relikvijar. Takvo mišljenje podupire bizantska stauroteka iz Limburga, relikvijar načinjen za Romana I., s relikvijom sv. Križa u zlatnom okviru i s prikazima serafina, kerubina, arhanđela i anđela. Pločicama se bavilo nekoliko stručnjaka. Matthias Mehofer i Verena Leusch zaključili su da su pločice izradili velikomoravski majstori. Točno je da pojasni ukrasi iz grobova 100, 240 i 490 pokazuju sličnosti s pločicama. U stilističkom smislu znakovit je i bizantski solid iz groba 480 s prikazom Mihajla III. koji drži labarum na reversu, te Krista s nimbom, s križem na reversu, a također i relikvijarni križ nađen uz crkvu br. 12. Najbliža slikana analogija ikonografiji pločica nalazi se u Homilijama Grgura Nazijanskog. Rukopis je nastao 880.-886. na carigradskom dvoru kao dar patrijarha Focija caru Baziliju I. To je najstarija sačuvana grčka kopija propovijedi Grgura Nazijanskog. Sadrži 46 minijatura na cijeloj stranici i više od 200 prikaza koji ne prikazuju samo scene iz Staroga i Novog zavjeta već i motive iz života Grgura Nazijanskog i cara Bazilija. Rukopis nije mogao biti uzorom pločicama iz Bojne, jer je bio isključivo posvećen Baziliju I. Iluminirani kodeksi koristili su se u najvišim krugovima bizantskog carskog dvora. Skupljali su ih, proučavali i naručivali istaknuti teolozi i učenjaci, pa i članovi carske obitelji. Sv. Konstantin koji je u pratnji Metodija došao u Veliku Moravsku 863., služio je na carskom dvoru prije svojega povijesnog putovanja. Njegov intelektualni razvitak temelji se na bizantskoj dvorskoj kulturi i na porukama kršćanske antike i patrologije, te poznavanju bizantske ikonografije. Bio je prijatelj Focijev i poznavao je spise Pseudo-Dionizija Areopagita, kako to opisuje rimski knjižničar Anastazije. Grgur Nazijanski utjecao je intelektualno i teološki na sv. Konstantina, koji mu je posvetio pjesmu tijekom studija u Carigradu. Pločice iz Bojne nastale su neovisno i ranije od najstarijega sačuvanog primjera Homilija iz Pariza (B. N., Gr. 510), i ne može se tvrditi da postoji izravna veza između njih i tadašnje bizantske imperijalne ikonografije. Prijevod: Vladimir P. Goss
Due to the increased demands for drilling and cutting tools working at extreme machining conditions, protective coatings are extensively utilized to prolong the tool life and eliminate the need for ...lubricants. The present work reports on the effect of a second MeN (Me = Zr, Cr, Mo, Nb) layer in WN-based nanocomposite multilayers on microstructure, phase composition, and mechanical and tribological properties. The WN/MoN multilayers have not been studied yet, and cathodic-arc physical vapor deposition (CA-PVD) has been used to fabricate studied coating systems for the first time. Moreover, first-principles calculations were performed to gain more insight into the properties of deposited multilayers. Two types of coating microstructure with different kinds of lattices were observed: (i) face-centered cubic (fcc) on fcc-W
N (WN/CrN and WN/ZrN) and (ii) a combination of hexagonal and fcc on fcc-W
N (WN/MoN and WN/NbN). Among the four studied systems, the WN/NbN had superior properties: the lowest specific wear rate (1.7 × 10
mm
/Nm) and high hardness (36 GPa) and plasticity index H/E (0.93). Low surface roughness, high elastic strain to failure, Nb
O
and WO
tribofilms forming during sliding, ductile behavior of NbN, and nanocomposite structure contributed to high tribological performance. The results indicated the suitability of WN/NbN as a protective coating operating in challenging conditions.
In the present work, the evolution of the microstructure in additively manufactured 17-4PH stainless steel, which was subjected to laser surface alloying with amorphous boron and nitrogen at the ...varying process parameters, was studied. The main aim was to improve surface hardness and hence potential wear resistance of the steel. Scanning electron microscopy, wavelength-dispersive X-ray spectroscopy (WDS), and Auger electron spectroscopy (AES) were used. It was shown that the final microstructure developed in the laser-melted zone (LMZ) is dependent on a variety of processing parameters (1 and 1.5 mm laser beam spot diameters; 200, 400, and 600 mm/min laser scan speeds), which primarily influence the morphology and orientation of the eutectic dendrites in the LMZ. It was metallographically proven that a fully eutectic microstructure, except for one sample containing 60 ± 4.2% of the eutectic, was revealed in the LMZ in the studied samples. The results of WDS and AES also confirmed alloying the LMZ with nitrogen. The formation of the boron eutectic and the supersaturation of the α-iron solid solution with boron and nitrogen (as a part of the eutectic mixture) led to enhanced microhardness, which was significantly higher compared with that of the heat-treated substrate (545.8 ± 12.59–804.7 ± 19.4 vs. 276.8 ± 10.1–312.7 ± 11.7 HV0.1).
The mechanisms of interactions between gramicidin A (gA) and dimyristoylphosphatidylcholine (DMPC) in monolayers formed at the air−water interface were studied by analyzing their mechanical, ...thermodynamical, and electrical properties evaluated from measurements of pressure−area isotherms and of Maxwell displacement currents (MDC). A contactless method of recording MDC enabled us to monitor changes in the charge state of the monolayer-constituting molecules and to find the relation between a phase state of the monolayer and structural transitions of gA. The peptide−lipid interactions were quantified in terms of the excess of Gibbs free energy, excess entropy, as well as the molecular dipole moments at various gA/DMPC molar ratios, at various temperatures (in the gel phase and also in the liquid-crystalline phase of DMPC molecule), and at various surface pressures. It was found that the strongest interactions between gA and DMPC took place at the gA/DMPC molar ratio at around 0.25. At this monolayer composition, the phospholipids, via their carbonyl moieties, dominantly interact with the single helical gA, which mostly stands upright on the surface and is anchored by its C-terminus to the water surface, and prevent the formation of the intertwined helical gA dimers. The optimum ratio was confirmed also by anomalous electrical behavior of electrical dipole moments derived from MDC measurements.
This work focuses on the problem of detection and prevention of stolen and misused secrets (such as private keys) for authentication toward centralized services. We propose a solution for such a ...problem based on the blockchain-based two-factor authentication scheme SmartOTPs, which we modify for our purposes and utilize in the setting of two and half-factor authentication against a centralized service provider. Our proposed solution consists of four entities that interact together to ensure authentication: (1) the user, (2) the authenticator, (3) the service provider, and (4) the smart contract. Out of two and a half factors of our solution, the first factor stands for the private key, and the second and a half factor stands for one-time passwords (OTPs) and their precursors, where OTPs are obtained from the precursors (a.k.a., pre-images) by cryptographically secure hashing. We describe the protocol for bootstrapping our approach as well as the authentication procedure. We make the security analysis of our solution, where on top of the main attacker model that steals secrets from the client, we analyze man-in-the-middle attacks and malware tampering with the client. In the case of stolen credentials, we show that our solution enables the user to immediately detect the attack occurrence and proceed to re-initialization with fresh credentials.
This paper focuses on the problem of detection and prevention of stolen and misused secrets (such as private keys) for authentication toward centralized services. We propose a solution for this ...problem, based on SmartOTPs, the two-factor authentication scheme against the blockchain, which is intended for smart contract wallets and utilizes one-time passwords (OTPs). We modify SmartOTPs for our purposes and utilize them in the setting of two-and-a-half-factor authentication against a centralized service provider. Out of two and a half factors of our solution, the first factor stands for the private key, and the second and a half factor stands for OTPs and their precursors (a.k.a., pre-images), where OTPs are obtained from the precursors by cryptoaraphically secure hashing. We describe the protocol for bootstrapping our approach as well as the authentication procedure. In the case of stolen creden-tials from the client, we show that our solution enables the user to immediately detect it and proceed to re-initialization with fresh credentials. We utilize blockchain-based identity management and decentralized identities of users to simplify the overhead of the registration process and reinitialization.
We present a user-assisted approach to extracting and visualizing structural features from point clouds obtained by terrestrial and airborne laser scanning devices. We apply a multi-scale approach to ...express the membership of local point environments to corresponding geometric shape classes in terms of probability. This information is filtered and combined to establish feature graphs which can be visualized in combination with the color-encoded feature and structural probability estimates of the measured raw point data. Our method can be used, for example, for exploring geological point data scanned from multiple viewpoints.
Evaluations of programs for the gifted have been criticized because of lack of objectivity and have often been perceived as a threat to programs rather than as an aid to program improvement. In an ...effort to overcome these criticisms, a university evaluation team and a public school program worked to develop evaluation instruments and procedures. The experiences of the first year of this cooperative effort are presented here to illustrate the issues, problems, and benefits of such an arrangement.
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