Effect of digital convergence on service bundling and competition in the telecommunications market in Bulgaria

Die Entwicklung von neuen Technologien, im Bereich der Informations- und Kommunikationstechnologien, führte zu Konvergenz zwischen ursprünglich unabhängigen Netzen und Diensten. Digitale Konvergenz bedeutet die Integration von verschiedenen Telekommunikationssystemen, die Digitalisierung von Netzwerken und das Entstehen von vielfältigen, neuen, innovativen Telekommunikationsdiensten. Die rasante Entwicklung der “Digitalen Konvergenz” führte zu radikalen Veränderungen auf dem Telekommunikationsmarkt. Herkömmliche Marktstrukturen verändern sich und neue Geschäftsmodelle entstehen. Telekommunikationssbereiche, die deutlich voneinander abgegrenzt waren, rücken immer mehr zusammen. Wegen Überschreitens der Klassischen Branchengrenzen steigt das Niveau des Wettbewerbs zwischen den Marktteilnehmern. Die Preise für Telekommunikationsdienste fallen aufgrund des steigenden Wettbewerbs. Mit zunehmender Konvergenz von Plattformen gibt es auch einen dauerhaften Trend zu gebündelten Diensten. Unter einem Bündelangebot versteht man die Zusammenführung verschiedener Produkte oder Dienstleistungen (z.B. Festnetzsprachtelefon-, Breitband-, Fernseh- und Mobilfunkdienste) zu einem Paket.The process by which different media as audio, video, data and voice communication services become digital and come to be delivered via one network is known as Digital Convergence. The business implications of Digital Convergence are profound. The economic organization of many fast growing industries is being transformed. Convergence is significantly altering traditional business models within the industries. Convergence is also changing the pricing strategies of the products adopted by the firms and the structure of their product offerings. Digital products are now usually tied to each other and sold as a combined product (package, bundle). At a market level convergence reshapes the market structure of the industries involved. Digital Convergence has created new market spaces and brought previously distinct industry sectors in competition with each other. Market players which used to be monopolies within their core industry are currently experiencing a dramatic change in their market structure – development of fiercely increasing competition. In some “new” converged markets customers have evidently benefited from this digital revolution. Convergence may provide significant benefits to customers such as price reduction

Geodemographic Aspects of Covid-19

The paper aims to address some of the major issues facing the pandemic development of Covid-19 from a geodemographic point of view. As at the time this paper was being prepared, the pandemic was still “raging” in much of Europe and North America, only intermediate - but nonetheless - official data have been used and analyzed in the study. Some relations between the population and its demographic structures such as gender, age, average population density, total population number, etc. have been considered in relation to the observed trends in the spatial distribution of the coronavirus. The suggested conclusions may prove to be subject of reconsideration, since those were only valid at the time of completion of the study (April 15, 2020).O artigo tem como objetivo abordar algumas das principais questões enfrentadas pelo desenvolvimento pandêmico do Covid-19 do ponto de vista geodemográfico. No momento em que este artigo estava sendo preparado, a pandemia ainda estava "em fúria" em grande parte da Europa e América do Norte, apenas dados oficiais intermediários - mas mesmo assim - oficiais foram usados ​​e analisados ​​no estudo. Algumas relações entre a população e suas estruturas demográficas, como sexo, idade, densidade populacional média, número total de populações etc. foram consideradas em relação às tendências observadas na distribuição espacial do coronavírus. As conclusões sugeridas podem vir a ser objeto de reconsideração, uma vez que eram válidas apenas no momento da conclusão do estudo (15 de abril de 2020).El documento tiene como objetivo abordar algunos de los principales problemas que enfrenta el desarrollo de la pandemia de Covid-19 desde un punto de vista geodemográfico. En el momento en que se estaba preparando este documento, la pandemia todavía estaba "furiosa" en gran parte de Europa y América del Norte, solo se usaron y analizaron datos oficiales intermedios, pero no obstante, en el estudio. Se han considerado algunas relaciones entre la población y sus estructuras demográficas, como el género, la edad, la densidad de población promedio, el número de población total, etc., en relación con las tendencias observadas en la distribución espacial del coronavirus. Las conclusiones sugeridas pueden ser objeto de reconsideración, ya que solo fueron válidas en el momento de la finalización del estudio (15 de abril de 2020).Sous le point du vue géodémographique, cet article vise à aborder des questions liées à la bataille contre la pandémie de la covid-19. Pendant l’écriture de ce texte, la pandémie était encore « en furie » en grand partie de l’Europe et de l’Amérique du Nord. Ainsi, on n’a décidé d’utiliser que des données officielles. En ce qui concerne à la distribution spatiale du coronavirus, on a associé des données relatives au chiffre total de la population, la structure démographique, le sexe et la densité démographique moyenne. Une fois qu’on a fini ce texte le 15 Avril 2020, les conclusions sont encore ouvertes

Current state of the urban network in Bulgaria

The paper deals with the classification of urban settlements in Bulgaria in a historical-geographical aspect, focusing on ​​the genesis and the formation of today's urban network in the country. The current state of the capital city, the small and the large cities have been revealed through certain examples. Those three groups of urban settlements develop at a different place, under different conditions and face an ambiguous future. In urbanization aspect, the agglomeration areas in Bulgaria have also been analyzed as specific spatial formations.O artigo trata da classificação dos assentamentos urbanos na Bulgária num aspecto histórico-geográfico, centrando-se na génese e na formação da atual rede urbana do país. O estado atual da capital, das pequenas e das grandes cidades tem sido revelado através de certos exemplos. Estes três grupos de aglomerados urbanos desenvolvem-se a um ritmo diferente, em condições diferentes e enfrentam um futuro ambíguo. No aspecto da urbanização, as áreas de aglomeração na Bulgária foram também analisadas como formações espaciais específicas.El artículo trata de la clasificación de los asentamientos urbanos en Bulgaria en un aspecto histórico-geográfico, centrado en la génesis y en la formación de la actual red urbana del país. El estado actual de la capital, de las pequeñas y de las mayores ciudades ha sido revelado a partir de ciertos ejemplos. En estos tres tipos de aglomerados urbanos desarrollan-se en un ritmo diferente, en diferentes condiciones y enfrentan un futuro ambiguo. En el aspecto de la urbanización, las áreas de aglomeración en Bulgaria he sido analizadas como formaciones espaciales específicas.Cet article vise à montrer la classification des établissements urbains sous le point du vue historico-géographique, en soulignant la genèse et la formation de l’actuel réseau urbain en Bulgarie. La capitale, les petites et les grandes villes possèdent ses spécificités et ne se développent pas selon les mêmes rythmes. Le résultat, c’est que son avenir est ambigu

Seasonality in tourism: trends and good practices in Rio de Janeiro, Shumen and the Douro Demarcated Region

The world, this planet where we live, boosts a diversity of territories, landscapes and distinct dynamics, which we can see in urban centres, whether in large metropolises such as Rio de Janeiro (Brazil), or in small inland cities, like Shumen (Bulgaria), an urban centre surrounded by a fabulous heritage and history, as well as in rural spaces, such as the Douro Demarcated Region (NE Portugal). Regardless of the scale of analysis and the typology of scenarios scattered across the continents, there are a wealth of landscapes and economic, social, architectural, historical and cultural heritages that need to be bolstered, while preserving their specificities and their authenticit

Definitive treatment of a basal cell carcinoma on the upper lip through the oral administration of Vismodegib

Basal cell carcinoma is the most common malignant neoplasm of the skin of the face in old, caucasian humans. The tumour growth slow and rarely has metastases. The clinical presentation is different. The main method for treating is radical surgical excision, but if the tumour is very big or there are metastases, there is a very effective target therapy with the peroral capsules Vismodegib 150mg. In this case we introduce a patient whit cancer of upper lip of preoperative target therapy whit Vismodegib 150mg, which destroy the tumour cells and help us to make cosmetic surgical excision

Wear Analysis of an Advanced Al–Al2O3 Composite Infiltrated with a Tin-Based Alloy

In this study, a hybrid material is produced, and the effect of different loads varying from 40 to 60 N against an EN-31 steel counter disk on its wear behavior under dry sliding conditions at room temperature is studied. The tribological behavior is studied via the pin-on-disk method and analyzed using primary wear parameters, such as the coefficient of friction (COF), mass wear, and specific wear rate. The obtained results are compared with the results for B83 babbitt under the same wear test conditions. Microstructural observation with scanning electron microscopy (SEM) is performed along with X-ray energy dispersive spectroscopy (EDX) for chemical analysis conduction. The results from the wear experiments indicate that the hybrid material possesses a lower COF, mass wear, and specific wear rate as well as a higher wear resistance in comparison to the B83 babbitt specimen when subjected to the same test conditions. The results from the wear experiments indicate that by applying different loads of 40, 50, and 60 N, the hybrid material possesses a lower mass wear, specific wear rate, and COF specifically at a load of 40 N in comparison to the B83 babbitt specimen under the same test conditions. It was also observed that by increasing the load under dry sliding friction, the hybrid material increases its mass wear and specific wear rate

Optimisation of an anode furnace refractory lining using distinct magnesia-chromite refractory types

In the present paper the results of a four-year investigation of the wear mechanisms affecting anode furnace linings are described. At the time when this study was initiated, the entire lining (apart from the tuyere blocks) consisted of a traditional direct-bonded magnesia-chromite brick. The latter suffered from acute wear due to the stringent chemical, thermal and mechanical conditions imposed. As a result of a microstructural study of samples prepared from industrially worn bricks, the major degradation mechanisms influencing the refractory lining were unravelled. On the basis of the identification of different wear zones in the lining, an optimised refractory configuration was proposed and installed in order to prolong the furnace campaigns. Distinct magnesia-chromite qualities were selected for the different wear zones. During the two following relinings worn bricks from various locations in the lining were collected and investigated. It was confirmed that refractory degradation in anode furnaces comes as a consequence of the combined action of chemical, thermal and mechanical drivers, which interact synergistically with one another. Depending on the region in the lining the relative importance of the drivers varies. Specific attention was given to the chemical wear mechanisms, namely: copper and slag components infiltration, forsterite formation and spinelisation. As a result of the installation of the new, zoned lining configuration a significant improvement of the overall lining lifetime was achieved.status: publishe

Production and Tribological Characterization of Advanced Open-Cell AlSi10Mg-Al₂O₃ Composites

In this study, advanced open-cell porous AlSi10Mg-Al2O3 composites have been successfully fabricated by replication of NaCl space holders. The tribological behavior under dry sliding conditions at room temperature of composites with different pore sizes was studied via the pin-on-disk method, and wear parameters, such as the coefficient of friction (COF) and mass wear, were determined. Micro-hardness tests have been performed to investigate the change in mechanical properties after the processing of the composite materials. Microstructural observation was conducted by means of light microscopy and scanning electron microscopy (SEM) along with chemical micro-analysis using an X-ray energy-dispersive spectroscopy (EDS) system. The obtained results revealed that the investigated AlSi10Mg-Al2O3 composites possess lower COF and mass wear than the open-cell porous AlSi10Mg material when subjected to the same test conditions. Furthermore, it was also reported that the effect of pore size is insignificant to the COF, and in relation to mass wear, the composite material with the larger pores shows better results

Fabrication and Characterization of Aluminum-Graphene Nano-Platelets—Nano-Sized Al₄C₃ Composite

Reinforcement of aluminum and aluminum alloys with graphene has been intensively practiced by researchers in the past dozen years. The role of Al4C3, which could be produced unintentionally or purposefully during the composite production, was controversial until it was found that nano-sized carbides were beneficial for strengthening the composites. aluminum-graphene-nano-sized Al4C3 composites were produced by us using the powder metallurgical method and subsequent annealing. The microstructure was investigated using light microscopy (LM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), transmission electron microscopy (TEM), and high resolution transmission electron microscopy HRTEM. Nano-sized carbides were found at the interface aluminum-graphene. The formation of a chemical bond between aluminum and graphene during annealing was proved. Lower values of the microhardness and strength characteristics of the composites after extrusion and subsequent annealing during which nano-sized carbides are formed were found in comparison with those obtained after extrusion. It could be supposed that the annealing processes contribute more to the reduction in microhardness and strength characteristics than nano-sized carbides contribute to its increase. The presence of a strong chemical bond between the graphene and the aluminum is manifested in the failure pattern, which is characterized by graphene nano-platelets and nano-sized carbides fracture and semi-pulled out or semi-slipped Al4C3 from the matrix