Article
Основные угрозы для надежности и безопасности дата-центров и методы борьбы с ними
The main threats to the reliability and information security data centers are designated and systematized. In first there are the technical threat of failure of the life support systems of various DC: server nodes, power system, air-conditioning, fire-fighting, provider's lines, cable systems, etc. In second there are external threats: in particular, the threat of DDoS-attacks (which now is one of the most critical threats). The ways to reduce and eliminate these threats are discussed. In particular, is discussed a variety of technical methods to improve the reliability and information security data centers, as well as legal (improving legislation).
On May 18-19, 2012, at the presidential retreat in Camp David in Maryland, U.S. president Barack Obama hosted the 38th annual G8 summit. The leaders discussed global economic growth, development, and peace and security. After less than 24 hours of face-to-face time among the leaders, they issued communiqué of only five pages. However, Camp David was a significant success. The leaders came together to effectively address the most pressing issues of the day while setting the direction for the summits that were to follow, including the summit of the North Atlantic Treaty Organization in Chicago, the G20 in Los Cabos, Mexico, and the Rio+20 Summit in Rio de Janeiro, Brazil. That success was propelled by several causes. The first is the set of strong global shocks were particularly relevant to a number of items on the agenda. This included the newest installment of the euro-crisis, spikes in oil and food prices, and the escalating violence in Syria. The second is the failure of the other major international institutions to address these challenges. The third is the club’s dedication to the promotion of democracy and its significance on issues such as the democratic transition in the Middle East and North Africa. The fourth is the high relative capabilities of G8 members, fuelled by the strength of the U.S. dollar, the Japanese yen and the British pound. The fifth is the domestic political control, capital, continuity, competence and commitment of the leaders in attendance. Camp David saw several G8 leaders returning for their sixth or seventh summit and leaders with a secure majority mandate and control of their legislative houses at home. Finally, the constricted participation at the remote and secluded Camp David Summit, a unique and original advantage of the G8 summit style, allowed for more spontaneous conversation and interpersonal bonds. Together, these interconnected causes brought the G8 back, as a broader, bigger, bolder centre of effective global governance.
A model for organizing cargo transportation between two node stations connected by a railway line which contains a certain number of intermediate stations is considered. The movement of cargo is in one direction. Such a situation may occur, for example, if one of the node stations is located in a region which produce raw material for manufacturing industry located in another region, and there is another node station. The organization of freight traffic is performed by means of a number of technologies. These technologies determine the rules for taking on cargo at the initial node station, the rules of interaction between neighboring stations, as well as the rule of distribution of cargo to the final node stations. The process of cargo transportation is followed by the set rule of control. For such a model, one must determine possible modes of cargo transportation and describe their properties. This model is described by a finite-dimensional system of differential equations with nonlocal linear restrictions. The class of the solution satisfying nonlocal linear restrictions is extremely narrow. It results in the need for the “correct” extension of solutions of a system of differential equations to a class of quasi-solutions having the distinctive feature of gaps in a countable number of points. It was possible numerically using the Runge–Kutta method of the fourth order to build these quasi-solutions and determine their rate of growth. Let us note that in the technical plan the main complexity consisted in obtaining quasi-solutions satisfying the nonlocal linear restrictions. Furthermore, we investigated the dependence of quasi-solutions and, in particular, sizes of gaps (jumps) of solutions on a number of parameters of the model characterizing a rule of control, technologies for transportation of cargo and intensity of giving of cargo on a node station.
Event logs collected by modern information and technical systems usually contain enough data for automated process models discovery. A variety of algorithms was developed for process models discovery, conformance checking, log to model alignment, comparison of process models, etc., nevertheless a quick analysis of ad-hoc selected parts of a journal still have not get a full-fledged implementation. This paper describes an ROLAP-based method of multidimensional event logs storage for process mining. The result of the analysis of the journal is visualized as directed graph representing the union of all possible event sequences, ranked by their occurrence probability. Our implementation allows the analyst to discover process models for sublogs defined by ad-hoc selection of criteria and value of occurrence probability
The geographic information system (GIS) is based on the first and only Russian Imperial Census of 1897 and the First All-Union Census of the Soviet Union of 1926. The GIS features vector data (shapefiles) of allprovinces of the two states. For the 1897 census, there is information about linguistic, religious, and social estate groups. The part based on the 1926 census features nationality. Both shapefiles include information on gender, rural and urban population. The GIS allows for producing any necessary maps for individual studies of the period which require the administrative boundaries and demographic information.
Existing approaches suggest that IT strategy should be a reflection of business strategy. However, actually organisations do not often follow business strategy even if it is formally declared. In these conditions, IT strategy can be viewed not as a plan, but as an organisational shared view on the role of information systems. This approach generally reflects only a top-down perspective of IT strategy. So, it can be supplemented by a strategic behaviour pattern (i.e., more or less standard response to a changes that is formed as result of previous experience) to implement bottom-up approach. Two components that can help to establish effective reaction regarding new initiatives in IT are proposed here: model of IT-related decision making, and efficiency measurement metric to estimate maturity of business processes and appropriate IT. Usage of proposed tools is demonstrated in practical cases.
I give the explicit formula for the (set-theoretical) system of Resultants of m+1 homogeneous polynomials in n+1 variables