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In this paper, an assessment of strength properties of the existing blade-disc dovetail joint is presented, taking the parametric optimization of its geometry. A sensitivity of the analysis was carried out to determine the relationship between selected geometric parameters and strength properties of the structure questioned. Results from experiments and computer simulations were compared. In addition, the fatigue life of the structure was analyzed for different materials and using the change of speed ranges and parameterization of geometry.

The aim of the study is to explore the intellectual structure of the field and fronts in research on energy efficiency in the context of cloud computing and thus to contribute to science mapping of the research field. The research process was driven by the following study questions: (1) what are the most influential publications in the research field? and (2) what are the research fronts in the research field? The method of direct citation analysis was employed in the research process. Data for analysis were obtained from the Scopus database and analyzed with the use of VOSviewer science mapping software. In response to the first question, we identified the most influential publications in the research field and analyzed their types (i.e., whether they are original research papers or rather the “context” papers e.g., survey or review papers, framework papers, challenges papers, and study papers). Moreover, a comparison analysis between the types of papers among the most cited “classical” publications and “emerging stars” was conducted. In response to the second research question, we identified five research fronts concentrated around the issues of: virtual machine management (“VM”); task-focus, concerning data replication, task consolidation, and task scheduling (“task”); energy efficiency (“energy”); modelling and optimization (“model”); and energy efficiency in the networking context (“network”).

The third chapter contains the description of the most important research and innovation aspects regarding cybersecurity and privacy. The first two sections have mainly descriptive character, and regard the area of research funding and the area of substantive research directions. The last two sections, in contrast, provide some conclusions regarding research in cybersecurity and privacy and also contain some suggestions about future common interests between the European Union and Japan.

The article concerns the issues of the scope of optimization of the gas turbine jet engine. These issues include limiting the weight and number of engine parts. One way to reduce the weight and number of components, including the compressor assembly, is to use the BLISK's replacement construction. The replacement construction should meet the strength requirement and the vibration spectrum as well. The paper presents a comparative analysis of the influence of rotational speed on the characters and the vibration frequency of the single rotor stage of the high pressure compressor. The analysis was carried out for two different design solutions of the blade-disk connection: the classical and integral. The comparative analysis focused on three important from the point of view of operation, the engine operating ranges: work on the ground (idle) and work during take-off and climb the aircraft.

Advances in the use of quantum tools in the relativistic metrology of the Solar System's space will be a decisive factor in the future level of planetary safety of the Earth in the face of threats from the impact of the Small Solar System Bodies (SSSBs). The initial concept of the Future Planetary Defense System (FPDS) provides for the preparation of computer physical models of the behavior of small celestial bodies including their collisions. The computer concept of the defensive space mission involves the preparation of 3D network- centric subsystems of small space vehicles as autonomous nodes connected by data transmission systems in space. As the leading technologies for connecting nodes into the system, laser and millimeter wave (MMW) technologies are proposed. The nodes of the system – space vehicles – will be equipped with very precise tools to search, detect, track, point and target dangerous asteroids. This part of the concept provides for the simulation of reactions of the defense system to the emergence of the threats to the Earth. It is fundamentally important to synchronize the system with very accurate and stable time signals from atomic and even pulsar clocks. In the scale of Solar System measurements of time, distance and angles, navigation, precise pointing, tracking and guidance are extremely difficult problems. Models of precise on-board atomic and pulsar clocks, and their synchronization are the basic problems of space metrology in their relativistic aspect. This is related to the time dilation phenomenon associated with the movement of clocks and the change in the frequency of emission and reception of signals in the gravitational field. This leads to the necessity of applying these two corrections changing the speed of the clock. We need to consider not only the system sensors, but also actuators. One of the most important aspects for consideration is the future high-power laser to combat small asteroids. The next example is a modern classic warhead to destroy the asteroid structure. In fact, there is a huge number of different problems already known, but the new one is that the computer simulation in the Solar System scale and near here to the Earth, according to the latest IAU resolutions ought to use the predictions of General Relativity in the weak-field limit: Parametrized Post- Post-Newtonian equations of "slow" motion. Our computer models of FPDS ought to be simulated in Reference Systems within the framework of General Relativity.

Statistical data clearly points out compressor train outage as one of the main reasons for the breakdown of aircraft power units. Outages are caused by various factors, including material conditions as the main one. Therefore, structural ultimate strength analysis of constructional raw material properties used in the production process of such an important part of an engine is not only of tremendous significance during the designing phase but also in a research phase and expertise associated with emergency situations. Considering the above-mentioned factors the article presents the outcomes of chemical composition, morphology, and phase structure of metallic material used to produce first row fan blades of RD-33 turbine jet engine, which is (currently) used by the Polish Air Force. Apart from typical material structure analysis, also the basic mechanical strength properties of materials have been determined including hardness, tensile, and impact tests. These may now constitute the basis for the analysis of substitute materials selection allowing the production of analyzed engine part.

The dynamic growth in the use of cloud computing systems results in increasing energy consumption. Consequently, more and more attention is given to energy efficiency issues both in research and theory development as well as the business practice of cloud computing systems. In spite of the rapid development of research, the field has not been mapped from the bibliometric perspective yet. This study aims at publication profiling and mapping the thematic structure of the cloud computing energy efficiency research field. Detailed research objectives include: (1) profiling scientific publications in the field, (2) identifying and exploring thematic research areas, (3) identifying emerging topics and discussing their potential as future research lines. The aforementioned objectives are translated into the following study questions: (1) What are the most productive nations, institutions, source titles, and scholars contributing to research on energy efficiency in cloud computing? (2) What does the thematic structure of the research field look like? (3) What are the “hot” research topics attracting scholars’ attention? The research methodology toolbox includes a combination of bibliometric descriptive studies (research profiling), science mapping (keyword co-occurrence analysis), and literature reviews (systematic literature review). Bibliometric data for analysis were elicited from the Scopus database. The VOSviewer software supported bibliometric analysis and data visualization.

The paper presents a conceptual design for an Unmanned Aerial Vehicle (UAV) of a MINI class, where the aircraft engineering is based on the parametrical approach with use of a master model. In addition, the algorithm for development of a virtual object is outlined as well. It is explained how grids are mapped on the surface of the UAV solid as well as applicability of these grids for aerodynamic modeling and strength analysis.

This article presents the results obtained during research on detection of unsolicited emails sent by botnets. The distinction from most existing solutions is that the presented approach is based on the analysis of network traffic, specifically the sequence and syntax of SMTP commands observed during email delivery. The authors present several improvements for detecting unsolicited email sources from different botnets (fingerprinting) that can be used during network forensic investigation.

Trust management is a unified approach to access control in open distributed systems, where decisions connected with access control are based on policy statements made by many principals. The family of Role-based Trust management languages (RT) is an effective means for representing security policies, credentials and relationship in distributed, decentralized, large scale access control systems. It delivers a set of role assignment credentials and is used in systems where the identities of users are not the most important form of identification. A credential gives information about the privileges of users and the security policies issued by (usually more than one) trusted authorities. The main purpose of this article is to show how some credential extensions can make a trust management system more useful in practice. It shows how security systems can be made more realistic by maintaining the procedure or including timing information.

The article touches aspects of security in Wireless Sensor Networks. It begins with a review and classification of existing types of threats and protection methods. The main part of the paper presents the results obtained during development of a threat detection system for WSN network. The described approach is based on a mobile platform which allows separation of security mechanisms and the software controlling the nodes of the protected network. The article describes the architecture of the system, chosen detection methods and details of the prototype implementation.

The problem of security protocols correctness is one of the main security problems connected with communication in computer networks. Several automatic tools for verifying properties of such protocols have been proposed and used. These tools allow to find weaknesses in many variants of the protocols proposed so far. However, these tools are not entirely bug-free. In this paper, we investigate some selected problems of well known, and widely used tools for protocols verification such as AVISPA, Scyther, VerICS or PathFinder. In our considerations, we propose a few examples of protocols that cannot be used in practice or do not ensure security goals, but are positively verified by some tools. We discuss problems connected with these observations and compare how different verification tools can solve them.

Trust management is an approach to access control in distributed open systems, where access control decisions are based on policy statements made by multiple principals. The family of Role-based Trust management languages (RT) is an effective means for representing security policies and credentials in decentralized, distributed, large scale access control systems. It provides a set of role assignment credentials. A credential provides information about the privileges of users and the security policies issued by one or more trusted authorities. The main purpose of this paper is to show how extensions can make the RT family languages more useful in practice. It shows how security policies can be made more realistic by including timing information, maintaining the procedure or parameterizing the validity of credentials.

The paper discusses how digital rights management (DRM) approach can be adapted to work in local or offline mode, without access to global central servers. The focus of this adaptation is not on protection of copyright in a commercial content setting but on restricting access to non-public documents to legitimate users. Therefore we work under assumption that protection against illegal copying is out of scope - any copy of the content is legitimate and can be accessed as long as the user identity and access rights can be properly verified.

In this paper, we investigate the problem of detecting correlations among datasets containing malicious data concerned with various types of network attacks and related events of the infections taken from a numerous sources and organizations. We propose a graph based technique to depict relationships between malicious data based on values of attributes related both to attackers and victims, and referred to different layers of the OSI model. The presented model can be used to fast, automatic identification of malware campaigns. The case study described in the paper demonstrates the performance of our method.

The classification of the massive amount of malicious software variants into families is a challenging problem faced by the network community. In this paper (The work was supported by the EU FP7 grant No. 608533 (NECOMA) and “Information technologies: Research and their interdisciplinary applications”, POKL.04.01.01-00-051/10-00.) we introduce a hybrid technique combining a frequent pattern mining and a classification technique to detect malicious campaigns. A novel approach to prepare malicious datasets containing URLs for training the supervised learning classification method is provided. We have investigated the performance of our system employing frequent pattern tree and Support Vector Machine on the real database consisting of malicious data taken from numerous devices located in many organizations and serviced by CERT Polska. The results of extensive experiments show the effectiveness and efficiency of our approach in detecting malicious web campaigns.

Topics below are rather undesired, but important, outcome not yet completed research on the aircraft airfoils, turbine and compressor blades, parametric design of airfoils, establishing the relationships based on the results of experiments in a wind tunnel, developing databases for determining the relationships between airfoil parameters and lift and drag coefficients. Reliable database created as a result of the research work allows to simulate the wind tunnel. Very early on, however, was necessary to extend the developed specialized software for a new applications, and it meant the need for generalization of software, e.g. for gas turbine engines, propellers, etc. But after some time it turned out, that in order to achieve the required accuracy, the changes are needed in the underlying assumptions, set decades ago. In addition, coordinate measuring machines and systems, and associated software were not always as accurate as expected. Concepts how to solve it and develop software carrying out these tasks are presented in the article. It is like to withdraw from the old path and look for a new path that will lead to the reliable data base. Processes related to air or gas flow should be similarly defined in all the specialized software applications (e.g. aircrafts and turbine engines). Accuracy (10-9 mm) achieved in virtual measurements within the integrated system can be used to verify the results of CMM and other measuring systems, provided that an appropriate software has been developed.

The paper presents the current and future research in the area of network and computer security at NASK, focusing on activities of CERT Polska and NISM teams. A large part of the activities are driven by the operational needs of CERT Polska, but independent research themes are also pursued. Most of the work concentrates either on threat detection methods (server and client honey pots) and threat intelligence or on distribution of security-related information. Other research areas are briefly described as well.

The topic of this paper is RT T , a language from the family of Role-based Trust management (RT) languages, which is used for representing security policies and credentials in distributed large scale access control systems. A credential provides information about the privileges of users and the security policies issued by one or more trusted authorities. RT languages combine trust management and Role Based Access Control features. RT T provides manifold roles to express threshold and separation of duties policies. A manifold role defines sets of entities whose cooperation satisfies the manifold role. The goal of this paper is introduction of time validity constraints to show how that can make RT T language more realistic. The core part of the paper describes a sound and complete inference system, in which credentials can be derived from an initial set of credentials using a set of inference rules.

The paper presents the recently started project which aims to develop a secure environment for processing of restricted information. The solution being developed by the consortium employs virtualization to allow data from different security domains to be processed on the same physical machine. The system can host Windows and Linux systems as secured guest operating systems. The proposed implementation offers advanced user authentication techniques and cryptographic protection. The project is expected to reach technology demonstrator phase in late 2012.

The article discusses the issue of balancing energy processes in turbine engines in operation in aeronautic and marine propulsion systems with the aim to analyse and evaluate basic operating parameters. The first part presents the problem of enormous amounts of energy needed for driving fans and compressors of the largest contemporary turbofan engines commonly used in long-distance aviation. The amounts of the transmitted power and the effect of flow parameters and constructional properties of the engines on their performance and real efficiency are evaluated. The second part of the article, devoted to marine applications of turbine engines, presents the energy balance of the kinetic system of torque transmission from main engine turbines to screw propellers in the combined system of COGAG type. The physical model of energy conversion processes executed in this system is presented, along with the physical model of gasodynamic processes taking place in a separate driving turbine of a reversing engine. These models have made the basis for formulating balance equations, which then were used for analysing static and dynamic properties of the analysed type of propulsion, in particular in the aspect of mechanical loss evaluation in its kinematic system.

For the last several years the combinatorial-cyclic method of optimization has been validated and expanded to new areas of applications. Although coordinate measurement analysis still is the main area of applications, the method is becoming a useful and unique tool in design optimization, reverse engineering (parametric design included), and virtual engineering. The case study aerodynamics of airplane and turbine airfoils, and simulation of wind tunnels is very difficult and promising as well. To solve all problems arising in these areas, an extensive software within the integrated CAD/CAM /CAE system has been developed, written in GRIP (SIEMENS NX 3.8).