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Наръчник на професиите
Full text linkThe book presents an overview of more than 50 professions. It contains links to interviews with professionals available for free use and innovative approach to presenting the professions
Thermal and phase analysis of Roman and Late Antiquity mortars from Bulgarian archaeological sites
No full textBy using the methods of archaeological chemistry—thermal analysis, powder X-ray diffraction analysis, and Fourier transform infrared measurements, 13 mortar samples from the Roman age and Late Antiquity were investigated. The results of the investigation showed the phase composition and probable raw materials that were used. The defined composition, type, and properties of the mortars prove that the same production technology was used in both the Roman and Late Antiquity. The exponential dependence of temperature of the point of inflection (Tinfl) by mass loss (ML) of calcite decarbonation was found, specifying that the decrease in mortar structure homogeneity and compactness leads to a decrease in calcite decarbonation temperature. All studied samples were defined as non-hydraulic lime mortars without any hygroscopic properties. The samples are of different binder to aggregate (B/A) ratios, as no relation between the B/A ratio and the purpose of mortar use was established. The experimental results related to the geological setting of the area provide additional information about people's knowledge of the environment. The results obtained are of fundamental and practical use, helping a future archaeological interpretation
Ancient Metallurgical Iron Slags—Chemical, Powder X-ray Diffraction and Mössbauer Spectroscopic Study
Full text linkThe production and trade of metals was the foundation of the economic wealth of many regions in the world, which makes the study of ancient metallurgical slags of primary importance. This type of study is relatively new for Bulgaria, where research in the field started in the late 1960s with chemical analysis of copper ore, slags, tools and finished goods from the ancient copper mine in the Ay-bunar area. Iron is one of the most commonly found elements in the earth’s crust and its deposits are widespread, including on Bulgaria’s territory. To this day, however, the study of iron slags from Bulgarian sites through chemical and phase analysis has almost never been explored. The application of these methods allows for the determination of the technology of the ancient metallurgical process. This study investigates iron slags from two Bulgarian archaeological sites, situated in close proximity to the Sarnevets hematite ore deposit, Sarnena Sredna Gora mountain. The ore bodies of the deposit outcrop on the earth’s surface and can be easily recognized due to the red coloring of the soil around them, which is a characteristic trait for finding iron deposits. In addition to the ancient mining activities in the region, proven by over 20 registered ancient mine workings,
ancient metallurgical activities were established as well, as proven by the discovered slags. A sample from the hematite ore was studied along with the slags, so that the percentage of iron extracted during the metallurgical process can be determined. The samples were studied through X-ray fluorescence analysis, powder X-ray diffraction analysis, and Mössbauer spectroscopy. The obtained results show that the slags are of the “furnace bottom slags” type, which is a product of metallurgical activity achieved through bloomery technology. The temperature range of the furnaces was determined to be around 900–1100 ◦C. The reduction of iron was possible at such low temperatures due to the ore’s type—self-fluxing hematite ore. The percentage of iron extracted from the ore was calculated to be
between 3.39% and 8.65%. Additionally, a relationship was established between the percentage of extracted iron, the Fe2+ content included in wüstite, and the viscosity index of the liquid slag. The acquired results are new to the archaeological studies conducted on Bulgaria’s territory and are a prerequisite for future interpretation and archaeological research
Икономическата и продоволствената сигурност като измерения на свободата от недостиг
Full text linkThis paper explores the essence of freedom from want as one of the pillars of the Human Security Concept. Its main dimensions are economic security and food security, which are analysed from the point of view of their specificity and characteristic features and their correlation with freedom from want
Недвижимото културно наследство: огледало на политическите трансформации в България
No full textС еклектичната си и хаотична архитектура, българските градове представляват своеобразен дневник на политическите трансформации през модерната и съвременната история на страната. В статията си, Ирена Тодорова поглежда различните архитектурни стилове през призмата на различните етапи в политическото развитието на модерна България. И проследява последователно разрушаването на османските архитектурни паметници с цел да се утвърди новата европейска идентичност на българите, навлизането на историцизма и сецесиона, утвърдили въпросната идентичност, краткия период на имперско самочувствие на българите, довел до разцвет на неовизантиката и пр. Както и кризата след войните и раждането на масовия човек и масовите идеологии, тоталитарните експерименти и затъването в псевдоавангардността на късното комунистическо безвремие
Модели и методи за оценяване на рискови стратегии
Full text linkСтратегическите рискове се разглеждат като съвременен проблем пред мениджмънта, както в тяхното разнообразие, така и в контекста на идентифициране на модели и методи за разрешаване на сложни и комплексни ситуации. Управленските решения все по-често се подпомагат от външни експерти и консултанти с цел оптимално анализиране на данните и намиране на най-доброто решение при реализирането на стратегически цели
Неслучилата се децентрализация в местното самоуправление в Република България
Full text linkThe purpose of the report is to present the ideas of decentralization in the local self-government of the Republic of Bulgaria and the policies of the Bulgarian governments for their implementation. Based on the review of existing scholarly research on the essence of decentralization in local self-government, as well as on the adopted strategic documents and normative acts in the period from 2006 to 2023, an attempt is made to defend the thesis that, in general, ideas for reforms in local self-government through decentralization have not been implemented in practice and have not led to an improvement in the efficiency of local administration in the Republic of Bulgaria. Decentralization in local self-government should be implemented through new policies and strategies
Archaeological bricks and tiles from Southeast Bulgaria - determination of raw material and production technology by chemical, phase, and thermal analyses
Full text linkThis work deals with Roman and Late Antique bricks and roof tiles from eight archaeological sites in Southeast Bulgaria. The samples’ study was through X-ray fluorescence, powder X-ray diffraction, Fourier transform infrared, and thermal analysis, supported by macro and micro observations. The results indicate the successful combination of the experimental methods to determine with great accuracy the mineral composition and type of the raw clay (regarding the content of carbonate phases), the firing technology, and some findings of high ceramic quality and durability over time. This work shows that the clay type (calcareous type - carbonate-rich clay or non-calcareous type - carbonate-poor clay) cannot be determined by using chemical analysis only. The clay type determination is only possible by combination with thermal analysis in the case of ceramic firing below the calcite decarbonation temperature and by taking into account only the CaO amount included in the clay as calcite, which is calculated from the measured mass loss of calcite decarbonation. The results prove that for a more precise determination of the ceramic firing temperature range, it is necessary to use not only the phase composition (mineral-thermometers), but also the structural features of minerals determined by Fourier transform infrared and thermal analyses. The results evidence the use of identical ceramic manufacturing technologies in the entire geographical area during the Roman and Late Antique periods and a clear perspective for future investigation. They also complement the known archaeological background by interpreting people’s knowledge continuity from the Roman age to Late Antiquity and giving insight into their economic and cultural life, based on the ceramic experimental investigations
It Takes Three to Tango: How a Cuban Ballerina Interpreted for Castro and Khrushchev
Full text linkThis text launches a series of articles under the image-based project ‘With the Aid of an Unidentified Interpreter: Putting Names to Faces on Historical Photos’ dedicated to the history of high-level interpreting. Here, the quest is to identify the interpreter at the two encounters between Nikita Khrushchev and Fidel Castro at Harlem’s Hotel Theresa and at the Soviet Mission in New York on 20 and 23 September 1960 based on a photo from the personal archive of Khrushchev’s assistant Vladimir Lebedev. This interpreter turned out to be Menia Martínez, a historic figure in Cuban ballet. Educated at the Vaganova School in St. Petersburg (Leningrad), she was proficient in Russian. The text looks at other professional and unprofessional interpreters who worked with the two leaders before, on, and after this trip to New York and whose work contributed to the development of Cuban-Soviet and East-West relations. The discussion draws on available visuals, memoirs, newspaper sources, and unclassified documents placing the discussion in the wider context of international relations at the time. The author is grateful to Menia Martínez, who, in a telephone conversation, has helped in clarifying some of the aspects of the matter under investigation