Information Flow for Optimized Management of Spectrum and Radio Resources in Cognitive B3G Wireless Networks

The Beyond 3G (B3G) radio landscape will consist of cognitive heterogeneous wireless networks, operating in the framework of diverse co-operative associations among different classes of operators and providers, for the accommodation of the demands of users with multimode and/or multihoming enabled terminals. In this context, the optimized spectrum and radio resource utilization will be key factor for accomplishment of the purposes of both users and operators/providers, namely the satisfaction of user’s needs and the augmentation of profit, respectively. In this paper, we focus on an architecture for the management and optimization of spectrum and radio resource utilization in such composite wireless environments, and we analytically present the respective information flow among and from/to the functional entities involved in this architecture. The proposed management architecture can operate in the framework of different business scenarios and is based on related work that has been conducted within the IEEE 1900.4 standard.     

Dynamics of Local Bond Correlations in FeSe x Te1−x by Inelastic Neutron Scattering

The dynamics of the local atomic pair correlations in the FeSe _x Te_1?x ( x = 0.1, 0.5, and 0.9) system were investigated using the dynamic pair density function analysis obtained from inelastic neutron scattering. Distinct differences are observed between the superconducting and nonsuperconducting compositions, particularly involving the local dynamics of the Fe-Fe correlations. The energy scale of the observed differences is between 25 and 30 meV. In the nonsuperconducting FeSe_0.1Te_0.9, the Fe-Fe correlations are enhanced with cooling that may signal stronger exchange interactions, while in the superconducting compositions of FeSe_0.9Te_0.1 and FeSe_0.5Te_0.5, they are suppressed.     

Hydrodeoxygenation of HMF over Pt/C in a continuous flow reactor

The three‐phase hydrodeoxygenation reaction of 5‐hydroxymethylfurfural (HMF) with H₂ was studied over a 10 wt % Pt/C catalyst using both batch and flow reactors, with ethanol, 1‐propanol, and toluene solvents. The reaction is shown to be sequential, with HMF reacting first to furfuryl ethers and other partially hydrogenated products. These intermediate products then form dimethyl furan (DMF), which in turn reacts further to undesired products. Furfuryl ethers were found to react to DMF much faster than HMF, explaining the higher reactivity of HMF when alcohol solvents were used. With the optimal residence time, it was possible to achieve yields approaching 70% in the flow reactor with the Pt/C catalyst. Much higher selectivities and yields were obtained in the flow reactor than in the batch reactor because side products are formed sequentially, rather than in parallel, demonstrating the importance of choosing the correct type of reactor in catalyst screening. © 2014 American Institute of Chemical Engineers AIChE J, 61: 590–597, 2015     

The Effects of Sc Alloying in Y56Al24Ni10Co10 Glasses on the Local Atomic Structure

Using neutron diffraction and the pair density function analysis, the effect of Sc alloying for Y on the local atomic structure of Y_56-x Al₂₄Ni₁₀Co₁₀ was investigated. The replacement of Y with Sc significantly changes the local atomic structure of amorphous Y_56-x Al₂₄Ni₁₀Co₁₀ as it promotes the formation of nanocrystalline particles. By comparing the structure function in reciprocal space of three alloys with x = 0, 0.1, and 0.2 (in atomic percent), small Bragg peaks are observed that increase in intensity proportionate with the amount of Sc. In real space, the substitution of Sc for Y leads to a drastic structural contraction most likely resulting from efficient cluster packing.     

eInvoke: Secure e-Invoicing based on web services

Electronic Invoicing services (e-Invoicing) will have a pivotal role in all the stages of handling Value Added Tax (VAT) for European Member States. Through a systematic introduction of e-invoicing, tax administrators will be able to implement new tools and procedures to carry out alternative controls that are less intrusive on the trading partners. Nevertheless, successful European e-invoicing implementations need to be in compliance with the corresponding European Directive 2001/115/EC. Most contemporary e-Invoicing implementations are proprietary and based on EDI, thus demonstrating great deficiencies. This paper presents an open electronic invoicing system named eInvoke, based on XML, XML cryptography and Web Services, that addresses all security requirements imposed by the Directive. Our e-Invoicing system has been accepted by “CEN/ISSS e-Invoicing Focus Group on Standards and Developments on electronic invoicing relating to VAT Directive 2001/115/EC” and its summary appears in CEN 2003 report [13] (pg 79–85), forwarded to EC as a recommendation. Alexandros Kaliontzoglou holds a Degree in Electrical and Computer Engineering from the National Technical University of Athens (NTUA), Greece. Since 2001 he is a PhD candidate in the area of Network and Information Systems Security at the Telecommunications laboratory in the School of Electrical and Computer Engineering of NTUA. Since April 2000 he has been working for Expertnet S.A. as a security engineer specializing at Web Technologies and network applications, and he has been active both in European research projects in the 5th and 6th Framework Programme (eMayor, Intelcities, SELIS, Reshen, La Mer, TSEC, WebSig) and projects of the Greek private sector. His research interests focus in the area of IT Security, Service Oriented Architectures, Web Services, Software Engineering, e-Government, e-Commerce and Public Key Infrastructures. Pelagia Boutsi has obtained the Degree in Informatics from the University of Piraeus, Greece, in November 2001. Since April 2002, she is a PhD candidate in the area of Security Information at the Computer Science Department of University of Piraeus. Since September 2001 she is employed at Expertnet S.A. as member of the Technical Department. Her current research interests are in the fields of PKIs, XML and XML Security. She has participated in European research projects and projects of the private sector. Despina Polemi has obtained the Degree in Applied Mathematics from Portland State University(USA) in 1984, Ph.D. in Applied Mathematics (Coding Theory) from City University of New York (Graduate Center) in 1991. She held teaching positions (1984– 1995) in Queens College and Baruch College of City University of NewYork. From 1991 to 1996 was assistant professor (tenure track) in State University of New Yorkat Farmingdale in the department of Mathematics. During 1996–2002 she was an associate researcher in ICCS. From 2000 to 2003 she acted as President of the BoD in a security consulting company Expertnet (www.expertnet.net.gr) and technical manager of the company from 2000–2004. She nowa Professor in the University of Piraeus R&D department. Her current research interests are in the fields of cryptology, security and e-business. She has over ninety publications in the above areas. She has received many research grants from various organizations such as the Danish Research Foundation, MSI Army Research Office/Cornell University, IEEE, State University of New York (SUNY), and The Graduate School of City University of New York (CUNY). She has been project manager (PM)/technical manger (TM) in security projects of various programmes such as National Security Agency (NSA), Dr. Nuala McGann Drescher Foundation, Greek Ministry of Defense, INFOSEC TELEMATICS for Administrations (COSACC), the Fifth Framework IST Programme (HARP, BEE, SEED, WebSig, TSEC, CORAS, RESHEN, SEED, La Mer, SECRETS) and the 6FP (e-Mayor, Intelcities, BIOSEC, SELIS). She participated in the EC security projects of the programs COST, ACTS, and NATOs’ security projects. She is a member of IEEE. She serves as an evaluator, reviewer and expert in the European Commission and consultant for the FP6.     

The Local Jahn-Teller Effect in (La/Sr)n+1MnnO3n+1

Lattice polarons play an important role in the mechanism of colossal magnetoresistance in the (La/Sr) _n+1Mn _n O_3n+1 manganites. Local lattice distortions were characterized by the pulsed neutron pair density function (PDF) analysis. The result shows that the doped holes form polarons related to the Jahn–Teller (JT) effect, both in the two-dimensional layered crystals (n=2) and in the perovskites (n=). The temperature effects are also similar in both systems suggesting that lattice polarons are largely independent of the crystal symmetry.     

Nonuniform metallic state in manganites and cuprates

Local lattice distortions suggesting nonuniform charge distributions were found to be a common feature of manganites and cuprates in the metallic state by neutron scattering studies. The atomic pair-density function (PDF) determined by pulsed neutron powder diffraction showed that in La_1-xSr_xMnO₃ doped holes form lattice polarons which persist even in the metallic state. In La_1.85Sr_0.15CuO₄ the energy width of the LO phonons around (π,0) determined by inelastic neutron scattering reflects magnetic satellites indicative of spin charge stripe formation. The implications of such nonuniform charge distribution for metal-insulator transition and superconductivity are discussed.     

Effects of Monoterpenoids, Acting Alone or in Pairs, on Seed Germination and Subsequent Seedling Growth

We compared the potential allelopathic activity of 47 monoterpe- noids of different chemical groups, by estimating their effect on seed germination and subsequent growth of Lactuca sativa seedlings. Apart from individual compounds, eleven pairs at different proportions were also tested. As a group, the hydrocarbons, except for (+)-3-carene, were the least inhibitory. Of the oxygenated compounds, the least inhibitory were the acetates; whenever the free hydroxyl group of an alcohol turned into a carboxyl group, the activity of the resulting ester was markedly lower (against both germination and seedling growth). Twenty-four compounds were extremely active against seedling growth (inhibiting it by more than 85%), but only five against seed germination. The compounds that were most active against both processes belonged to the groups of ketones and alcohols; they were terpinen-4-ol, dihydrocarvone, and two carvone stereoisomers. We used a model to investigate whether compounds acted independently when applied in pairs. The combined effect varied. In half of the cases, it followed the pattern expected under the assumption of independence; in the rest, either synergistic or antagonistic interactions were found in both germination and elongation. However, even in cases of synergistic interactions, the level of inhibition was not comparable to that of a single extremely active compound, unless such a compound already participated in the combination. The specific structural factors that operate and determine the activity of monoterpenoids still remain rather obscure. The same holds true for the combined effect; its character cannot in general be predicted on the basis of individual compounds acting alone.     

An adaptive partitioning approach for mining discriminant regions in 3D image data

Mining discriminative spatial patterns in image data is an emerging subject of interest in medical imaging, meteorology, engineering, biology, and other fields. In this paper, we propose a novel approach for detecting spatial regions that are highly discriminative among different classes of three dimensional (3D) image data. The main idea of our approach is to treat the initial 3D image as a hyper-rectangle and search for discriminative regions by adaptively partitioning the space into progressively smaller hyper-rectangles (sub-regions). We use statistical information about each hyper-rectangle to guide the selectivity of the partitioning. A hyper-rectangle is partitioned only if its attribute cannot adequately discriminate among the distinct labeled classes, and it is sufficiently large for further splitting. To evaluate the discriminative power of the attributes corresponding to the detected regions, we performed classification experiments on artificial and real datasets. Our results show that the proposed method outperforms major competitors, achieving 30% and 15% better classification accuracy on synthetic and real data respectively while reducing by two orders of magnitude the number of statistical tests required by voxel-based approaches.     

Kinetic and reaction mechanisms of calcium bisulfite catalytic oxidation

In this paper, the oxidation of calcium bisulfite in the presence of ferrous ions as a catalyst is studied in a laboratory scale apparatus at a fixed oxygen partial pressure (21.3 kPa) and at a temperature of 45 °C. The analysis of the experimental results, carried out by using the theory of mass transfer with chemical reaction, indicates that the slow reaction regime has been explored, and the transition from the kinetic to the diffusional subregime identified. A kinetic analysis allows to develop a reaction rate equation, assuming that the bisulfite oxidation in the presence of ferrous ions follows a parallel reaction mechanism; the resulting overall reaction rate has been found to be of first order with respect to ferrous ion concentration and of three halves with respect to bisulfite concentration. Moreover, the catalytic effect of ferrous ions has been compared with that of manganese ions previously studied, showing that ferrous is a catalyst more active than manganese.