Top PDF On Subjective Trust Management, Journal of Telecommunications and Information Technology, 2008, nr 4

On Subjective Trust Management, Journal of Telecommunications and Information Technology, 2008, nr 4

On Subjective Trust Management, Journal of Telecommunications and Information Technology, 2008, nr 4

should aggregate values for each criterion to present to user single vector of aggregated criteria satisfaction levels. We propose to consider use of the WOWA aggregation tech- nique as well suited approach for this case. As mentioned above particular agent while assessing reliability of the in- former can use several techniques. However the problem it- self is not an easy task and very often agents cannot a priori assess the reliability of others, especially in environments when very rarely there exists more than one interaction in- volving particular pair of agents. If environment/system allows to monitor reliability of the information, agent can derive a kind of rating for messages he acquired from other parties. If no such functionality is available, messages can be arranged with respect to the date they were created. In either case derived ratings can be used to establish the vector of importance weights as described in WOWA def- inition. WOWA gives us also possibility to express atti- tude towards values of selected criteria satisfaction levels. If particular agent requires that all messages regarding inter- actions with other party should show high level of perfor- mance with respect of a given criteria, he should set prefer- ential weights to form an “anding” operator. If he requires at least one message to be highly satisfactory he should form more “oring” operator. The question of “orness” and “andness” are described in [5].
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Quality of service support, security and OSPF interconnection in a MANET using OLSR, Journal of Telecommunications and Information Technology, 2008, nr 2

Quality of service support, security and OSPF interconnection in a MANET using OLSR, Journal of Telecommunications and Information Technology, 2008, nr 2

A tactical network is not isolated, it should be able to com- municate with other networks, more conventional. These networks generally use open shortest path first (OSPF). Consequently, an interconnection should be done between the OLSR and the OSPF routing domains. We show how to take advantage that both protocols are link based routing protocols in order to perform such an interconnection. This OLSR-OSPF interconnection is described in Section 4. The MANET in general and OLSR networks specifically, are of prime interest to DGA/CELAR (French MoD). Hence in partenership with INRIA, which developped and installed a MANET/OLSR platform at CELAR (Technical Defense Center for Information Warfare), such OLSR-based MANETs have been experimented and their features and performances have been evaluated.
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An Improved Downlink MC-CDMA System for Efficient Image Transmission, Journal of Telecommunications and Information Technology, 2017, nr 4

An Improved Downlink MC-CDMA System for Efficient Image Transmission, Journal of Telecommunications and Information Technology, 2017, nr 4

in 1988, from University of Sci- ences and Technology of Oran (USTO, Algeria), an M.Sc. in 1991, from Sidi Bel Abbes Uni- versity, and a Ph.D. in 1997, from USTO. Since 1991, he works at the Department of Telecommunications at the Uni- versity of Sidi Bel Abbes and performs his research at the Telecommunications and Digital Signal Processing Lab- oratory. His research interests include signal processing for telecommunications, communication over multipath and fading channels, wireless networks, channel coding for communication networks. He has more than 60 publica- tions in specialized journals with impact factors.
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WEALTHY – a wearable healthcare system: new frontier on e-textile, Journal of Telecommunications and Information Technology, 2005, nr 4

WEALTHY – a wearable healthcare system: new frontier on e-textile, Journal of Telecommunications and Information Technology, 2005, nr 4

This tendency is changing dramatically the common life style, as well as the needs of people. Citizens are becoming more and more used in telecommunicating and in manag- ing information, and the idea of a surrounding virtual world is no more an alien concept. New tools are being developed to be used every where, during normal life, capable to help people to increase their health status awareness, to train them to act at a preventive level by modifying their life style, to give them the feeling of a reassuring link. The in- teraction between physician and patient is growing in qual- ity and the contribution is coming from both sides. New systems designed to be minimally invasive, based on flexible and smart technologies conformable to the hu- man body are conceived to improve the autonomy and
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Enhancement of Power Efficiency in OFDM System by SLM with Predistortion Technique, Journal of Telecommunications and Information Technology, 2011, nr 4

Enhancement of Power Efficiency in OFDM System by SLM with Predistortion Technique, Journal of Telecommunications and Information Technology, 2011, nr 4

In this paper, we have used SLM technique with predistor- tion. Predistortion technique is applied at the transmitter side [8]–[12]. The main idea of predistortion is to shape the transmitted data symbols (data predistortion) or the in- put signal of the HPA amplifier (signal predistortion) so that the output signal of the HPA is less distorted. Pre- distortion technique improves the power density spectrum of the transmitted signal and bit error performance. This paper is organized as follows. In Section 2, we inves- tigate the distribution of PAPR based on the characteristics of the OFDM signals and nonlinear transmitter characteris- tics. Section 3, explains SLM and predistortion technique. Simulation results are shown in Section 4, and Section 5 contains the conclusion.
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Impact of Signaling System Performance on QoE in Next Generation Networks, Journal of Telecommunications and Information Technology, 2009, nr 4

Impact of Signaling System Performance on QoE in Next Generation Networks, Journal of Telecommunications and Information Technology, 2009, nr 4

These functions check if the user sending a call is au- thorized to use the EuQoS system. Next, the SIP proxy initiates the codec agreement with the called user. Af- ter the codec agreement, the first resource manager (RM) in the way checks whether the end-to-end QoS path to the called user exists and could provide the QoS guaran- tees required by the associated end-to-end CoS. The RM in the access domain periodically receives from the QoS routing protocol, the information about the QoS paths, i.e., the end-to-end paths with predefined QoS guarantees (in the form of target values for QoS parameters as IPTD, IPDV, IPLR). The QoS routing protocol is an enhanced ver- sion of border gateway protocol called EQ-BGP [2], [20], which builds end-to-end QoS paths on multi-domain net- work.
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Journal of Telecommunications and Information Technology, Blob Extraction Algorithm in Detection of Convective Cells for Data Fusion, 2019, nr 4

Journal of Telecommunications and Information Technology, Blob Extraction Algorithm in Detection of Convective Cells for Data Fusion, 2019, nr 4

Level 1 assesses variables describing the state of entities, for example: position, velocity, size, etc. In order to per- form entity assessment, information about such variables has to be extracted from data pre-processed in level zero. Considering computer vision, the problem revolves around detection of entities in images. Images consist of blobs – areas of an image sharing similar or constant properties. This paper describes a novel blob detection technique ap- plied with regard to radar images in data fusion schemes. This technique will be used to extract important variables for high level data fusion.
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Reference Point Method with Importance Weighted Partial Achievements, Journal of Telekommunications and Information Technology, 2008, nr 4

Reference Point Method with Importance Weighted Partial Achievements, Journal of Telekommunications and Information Technology, 2008, nr 4

Włodzimierz Ogryczak is a Professor and Deputy Direc- tor for Research in the Institute of Control and Computation Engineering (ICCE) at the War- saw University of Technology, Poland. He received both his M.Sc. (1973) and Ph.D. (1983) in mathematics from Warsaw University, and D.Sc. (1997) in computer science from Polish Academy of Sciences. His research interests are focused on models, computer solutions and interdisciplinary appli- cations in the area of optimization and decision making with the main stress on: multiple criteria optimization and decision support, decision making under risk, location and distribution problems. He has published three books and numerous research articles in international journals. e-mail: wogrycza@ia.pw.edu.pl
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Electromagnetic Scattering by a Cylinder in a Lossy Medium of an Inhomogeneous Elliptically Polarized Plane Wave, Journal of Telecommunications and Information Technology, 2019, nr 4

Electromagnetic Scattering by a Cylinder in a Lossy Medium of an Inhomogeneous Elliptically Polarized Plane Wave, Journal of Telecommunications and Information Technology, 2019, nr 4

B.Sc. in Clinical Engineering in 2005 and M.Sc. degree in Biomedical Engineering “cum laude” from “La Sapienza” Uni- versity of Rome, Italy in 2008. He earned his Ph.D. in Elec- tromagnetism from the Depart- ment of Information Engineer- ing, Electronics and Telecom- munications of the same Uni- versity in 2014. In June 2014 and in May 2015, he won the prize “Young Scientist Award” from URSI (Interna-

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Closed-form Distribution and Analysis of a Combined Nakagami-lognormal Shadowing and Unshadowing Fading Channel , Journal of Telecommunications and Information Technology, 2016, nr 4

Closed-form Distribution and Analysis of a Combined Nakagami-lognormal Shadowing and Unshadowing Fading Channel , Journal of Telecommunications and Information Technology, 2016, nr 4

Fig. 3. PDF of combined NL shadowing and unshadowing for urban, suburban and highway ( µ = −3.914, σ = 0.806, m = 2). In Fig. 4, AOF has been plotted for different time-share factor A . This figure gives details about variation in the total amount of fading with variation in probabilistic change in the fading conditions for a combined fading scenario. Initially, with A = 0, only Rician condition dominates and hence AOF remains very low. With increase in A, fading is dominated by multipath shadowing condition and hence

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Implementation of Selected Spectrum Sensing Systems for Cognitive Radio Networks using FPGA Platform, Journal of Telecommunications and Information Technology, 2018, nr 4

Implementation of Selected Spectrum Sensing Systems for Cognitive Radio Networks using FPGA Platform, Journal of Telecommunications and Information Technology, 2018, nr 4

Hadeel S. Abed obtained her B.Sc. from the Information and Communication Engineer- ing Department at the Al- Khawarizmi College of Engi- neering, University of Baghdad, Iraq, in 2014, and M.Sc. in Net- work Engineering and Internet Technologies from the Univer- sity of Al Nahrain, Baghdad, Iraq in 2017. Since 2016 she has been working as a part time lecturer at the Information and Communication Engineering Department of the Al- Khawarizmi College of Engineering, University of Bagh- dad. Her research interests include cognitive radio net- works.

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Comparative Study of PSO and CMA-ES Algorithms on Black-box Optimization Benchmarks, Journal of Telecommunications and Information Technology, 2018, nr 4

Comparative Study of PSO and CMA-ES Algorithms on Black-box Optimization Benchmarks, Journal of Telecommunications and Information Technology, 2018, nr 4

The remainder of this paper is organized as follows. A short survey of black-box techniques is presented in Section 2. A brief description of two bio-inspired algo- rithms, CMA-ES and PSO in their local and global ver- sions, is presented in Section 3. The overview of implemen- tation, organization and usage of the benchmark COCO and BBOB test bed platform is presented in Section 4. The ex- perimental procedure and the performance measures are presented in Section 5. The results of performance evalu- ation of both optimization algorithms, conducted with the use of various benchmarks, are presented and discussed in Section 6. Finally, conclusions are drawn in Section 7.
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QoS-based Joint User Selection and Scheduling for MU-MIMO WLANs, Journal of Telecommunications and Information Technology, 2017, nr 4

QoS-based Joint User Selection and Scheduling for MU-MIMO WLANs, Journal of Telecommunications and Information Technology, 2017, nr 4

the downlink capacity. As a result, the AP undergoes lim- ited CSI feedback exchanges. 3.3. DL Feedback Mechanism The user scheduling in the proposed scheme utilizes the channel gain obtained from the individual user stations dur- ing the feedback stage. Based on the information obtained from the user station, the AP prepares a channel trace that is basically composed of two preference metrics. This is termed as dual alignment metric. The first one gives the channel gain magnitude of the user station, and the other metric gives the probe direction of the desired user station. We shall look into the concept of these metrics in detail. For each user k, compute v k the component of h k orthogo- nal to the subspace spanned by  v (1) , v (2) , . . . , v (| S|) :
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Robust and Accurate Iris Segmentation Algorithm for Colorand Noisy Eye Images, Journal of Telecommunications and Information Technology, 2010, nr 4

Robust and Accurate Iris Segmentation Algorithm for Colorand Noisy Eye Images, Journal of Telecommunications and Information Technology, 2010, nr 4

Due to the color richness of irises it is difficult to define their characteristic color subspace and distinguish the iris area based only on its color. However information about the color can be used to find the boundary between the iris and the sclera and between the iris and the pupil. If the reflections are removed the pupil area is the darkest part of the image regardless of the color component used. On the other hand, the iris area contains at least one color com- ponent which has a significant higher values than for the pupil area. Therefore in order to distinguish the pupil and the iris we generate a monochrome image with intensity values of each pixel equal to maximum intensity values of red (R), green (G) and blue (B) color components of the source eye image I pupil -iris = max(I R , I G , I B ). The sclera is the lightest part of the eye image. Usually all the color components have very high intensity values in the sclera region. Therefore in offer to find the outer iris bound- ary we generate second monochrome image with intensity values equal to the minimum of the original image color components I sclera -iris = min(I R , I G , I B ).
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L-SCANN: Logarithmic Subcentroid and Nearest Neighbor , Journal of Telecommunications and Information Technology, 2016, nr 4

L-SCANN: Logarithmic Subcentroid and Nearest Neighbor , Journal of Telecommunications and Information Technology, 2016, nr 4

Based on its objective, data protection can be divided into two categories. The first is securing data in a file or trans- action. This is done by using either encryption [1], transfor- mation [2] or steganography [3]. The second is protecting data which reside in a network. In this case, the control is usually carried out by an intrusion detection system (IDS). Based on [4], IDS can be grouped into two categories. The first is signature-based IDS, which uses records of known attack. If an activity matches with any of that record, then

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Hybrid Models for the OWA Optimization, Journal of Telecommunications and Information Technology, 2016, nr 4

Hybrid Models for the OWA Optimization, Journal of Telecommunications and Information Technology, 2016, nr 4

[17] IBM, IBM ILOG CPLEX Optimization Studio [Online]. Available: http://www-03.ibm.com/software/products/en/ibmilogcpleoptistud/ Paweł Olender is an Assistant Professor in the National Insti- tute of Telecommunications in Warsaw. He received his M.Sc. and Ph.D. in Computer Science from the Warsaw University of Technology, Poland, in 2008 and 2015, respectively. He has participated in projects related to data warehousing and analy- sis for a telecommunication op- erator. His research interests are focused on modeling, de- cision support, optimization, machine learning and data mining.
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Traffic Engineering in Software Defined Networks: A Survey, Journal of Telecommunications and Information Technology, 2016, nr 4

Traffic Engineering in Software Defined Networks: A Survey, Journal of Telecommunications and Information Technology, 2016, nr 4

2 Computer Center, Panjab University, Chandigarh, India Abstract—An important technique to optimize a network and improve network robustness is traffic engineering. As traf- fic demand increases, traffic engineering can reduce service degradation and failure in the network. To allow a network to adapt to changes in the traffic pattern, the research com- munity proposed several traffic engineering techniques for the traditional networking architecture. However, the traditional network architecture is difficult to manage. Software Defined Networking (SDN) is a new networking model, which decou- ples the control plane and data plane of the networking de- vices. It promises to simplify network management, intro- duces network programmability, and provides a global view of network state. To exploit the potential of SDN, new traf- fic engineering methods are required. This paper surveys the state of the art in traffic engineering techniques with an em- phasis on traffic engineering for SDN. It focuses on some of the traffic engineering methods for the traditional network ar- chitecture and the lessons that can be learned from them for better traffic engineering methods for SDN-based networks. This paper also explores the research challenges and future directions for SDN traffic engineering solutions.
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Network Selection in Wireless Heterogeneous Networks: a Survey, Journal of Telecommunications and Information Technology, 2018, nr 4

Network Selection in Wireless Heterogeneous Networks: a Survey, Journal of Telecommunications and Information Technology, 2018, nr 4

To recapitulate: MADM methods are widely used to solve the network selection problem, this is due to the fact that network selection involves the same problems as are solved by MADM. Moreover, these methods are known for their ease of use, clarity and low complexity of computation. The disadvantages of these methods are listed below. Firstly, these methods do not offer the same level of perfor- mance with respect to different services (VoIP, video calls and web browsing) (Table 4). Secondly, they suffer from the problem of ranking abnormality, i.e. the phenomenon occurs in the MADM methods when an exact replica or a copy of an alternative is introduced or eliminated. Authors in [20] have shown that the rank reversal prob- lem occurs in the majority of well-known MADM methods. This problem has been addressed in other works [21], [22], by introducing specific modifications, but the original ver- sions of MADM methods suffer from the rank reversal problem. Additionally, the AHP method is very compli- cated and requires complex computations when calculating the vector of weights. Due to all these reasons, we can say that MADM are a good solution, but the lack of a general method that would be suitable for all kinds of services is a problem.
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Comparative Study of Supervised Learning Methods for Malware Analysis, Journal of Telecommunications and Information Technology, 2014, nr 4

Comparative Study of Supervised Learning Methods for Malware Analysis, Journal of Telecommunications and Information Technology, 2014, nr 4

Most of the data collected in the n6 database is updated daily. The n6 platform provides tools for sorting the in- cidents. Due to a sophisticated tagging system, incidents can be assigned to unique entities (e.g. based on IP address and AS numbers). Data are collected into special pack- age, which keeps an original source format (each source in separate file). Additionally it is possible to provide other information, e.g., about C & C servers that are not consisted in a client network, but can be utilized to detect infected computers. Information about malicious sources is trans- ferred by the platform as URL’s, domain, IP addresses or names of malware.
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Detecting Security Violations Based on Multilayered Event Log Processing, Journal of Telecommunications and Information Technology, 2015, nr 4

Detecting Security Violations Based on Multilayered Event Log Processing, Journal of Telecommunications and Information Technology, 2015, nr 4

Transport layer is responsible for collecting log messages from various sources and passing them to the log-col- lecting server, where the analysis is done. The transport must guarantee confidentiality and transmitted data in- tegrity, achieved by using rsyslog software [1]. This layer secures a copy of all incoming logs (crucial in security log management according to the guidelines [2]), which en- ables discovery of data tampering attempts. Preserving logs in remote localization enables incident reconstruction even after unrecoverable machine failure [3]. Moreover, pre- serving three timestamps for every log (generation, server reception, database insert) can indicate server downtime or communication disruption, which can be relevant for fur- ther investigation.
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