Miracle-dz/UniFAR-FTUs huggingface dataset:
Adaptive Spectrum Sensing Algorithm Under Different Primary User Utilizations

Spectrum sensing is one of the key technologies to realize dynamic spectrum access in cognitive radio (CR) systems. In this letter, a novel adaptive threshold spectrum sensing algorithm is proposed to achieve an efficient trade-off between the detection and false alarm probability. The proposed adaptive threshold algorithm demonstrates a better spectrum efficiency for both primary users (PUs) and secondary users (SUs) in comparison with the conventional fixed one. A closed-from expression between PUs' spectrum utilization ratio and the proposed adaptive threshold is derived and simplified.
Performance of LTE linear MIMO detectors: Achievable data rates and complexity

In this study we analyze performance of linear single user multiple-input multiple-output (SU-MIMO) detector applied in 3GPP LTE wireless systems. We consider minimum mean square error (MMSE) linear detectors based on (i) explicit matrix inversion, and (ii) adaptive gradient algorithm. We present the average achievable data rates as a function of different mobile terminal speeds, using the Jakes model, with symbol-by-symbol temporal variations. Mean and cell-edge rates are determined using two-dimensional multi-cell model. The LTE-specific reference signal (i.e., pilot) arrangements are considered. In addition, the implementation complexity is analyzed. At the expense of higher implementation complexity, for higher mobile terminal speeds and signal-to-interference-and-noise ratio (SLNR) the detector based on explicit matrix inversion outperforms the one based on the adaptive gradient algorithm. Furthermore, we show that a corresponding single-input multiple-output (SIMO) solution outperforms MIMO for moderate and high mobile terminal speeds. In addition, complexity-wise the SIMO transmission is shown to be more efficient. The results indicate that the MIMO transmission with linear detection should be applied only in a very limited number of channel conditions: (i) high SINR, and (ii) low mobility. This study may be used as a basis for establishing a trade-off between the data rates, complexity and multiple antenna arrangements.
Corporate social responsibility disclosure : an examination of framework of determinants and consequences

This study presented a framework to explain corporate social responsibility disclosure (CSD) in terms of determinants and consequences. The study is dealing with quantity and quality of CSD in both annual and stand alone reports. The framework is based on legitimacy theory as appropriate theoretical background for CSD, and the main idea in this theoretical framework is that CSD is a function of social pressure on companies concerning their social responsibility. The framework has started with explain the level of social pressure at the country level to explain the differences of the level of CSD among countries. It is argued that the interaction between economic level, culture and the level of corporate governance determine the level of social pressure in a given country. The level of CSD at the company level is determined according to two dimensions; the degree of social pressure that face each company and how each company responses to this pressure. It is argued that, on one hand, the interaction between corporate characteristics and media coverage of the company determine the degree of social pressure that face a company and on the other hand corporate governance mechanisms determine how each company responses to pressure. The last point in framework explains that the direct consequence for CSD is improving corporate social reputation. The empirical results support, to large extent, the framework. At a country level, both cultural values and economic level determine the level of social responsibility disclosure in the country. Concerning determinants of CSD at a company level, it appears that quantity of CSD, and to lesser extent quality of CSD, can be determined according to the following variables: corporate size, type of activity, media pressure, board size, the presence of corporate responsibility committee as a board committee, and ownership diffusion. With regard to the consequences of CSD, the empirical evidence indicates that CSD significantly influences corporate social reputation, while it has no impact on corporate market value.
Ancient Polychromy

Digital reconstruction of ancient polychromy is a relatively recent phenomenon in the history of archaeological and architectural heritage documentation. It has emerged as a result of new interest in the experimental archaeology and the technological development of computer graphic tools. Therefore, this article presents a project aimed at the scientific reconstruction of the original polychromy and the realistic rendering of an ancient sarcophagus, obtained with the use of some open source tools. In particular, starting from the accurate study of a polychrome Roman sarcophagus (National Roman Museum in Rome, inv. no. 125891), we show how the MeshLab tool was used to support the polychrome reconstruction stage and how Blender (or, rather, a combination of MeshLab and Blender) was used to achieve a more sophisticated visual presentation of the current and reconstruction ancient colour. A central role has been given to the rendering of different and overlapped layers of paint.
Integrity of Relay Misbehavior Detection in Wireless Network Coding

We consider the maximum a posteriori (MAP) approach in detecting the misbehaving relay that injects false data and/or adds channel errors into the network encoder in noisy multiple access relay networks. The proposed approach is optimal in the sense of minimizing the probability of incorrect detection. The integrity (trustworthiness) of relay misbehavior detection is determined as a function of the information transmission rate and the signal-to-noise ratio in Rayleigh fading channel. To enhance the integrity of detection outcome, we consider the MAP detection aided by tracing (reference) bits. The improvement of integrity by imposing overhead (tracing bits) is analyzed as a function of overhead amount.
On the Security of a Multi-use CCA-Secure Proxy Re-encryption Scheme

In proxy re-encryption (PRE), a semi-trusted proxy can convert a cipher text originally intended for Alice into one which can be decrypted by Bob, while the proxy can not know the corresponding plaintext. PREcan be classified as single-use PRE and multi-use PRE according to the times the cipher text can be transformed. In multi-use PRE schemes, the cipher text can be transformed from A to B and to C and so on. In CCS'09 (post session), Wan get al. proposed a multi-use unidirectional CCA-secure proxy re-encryption scheme. Unfortunately, we show their proposal is not CCA-secure in the corresponding security models by giving concrete attacks.
Effect of ultraviolet light irradiation on bond strength of fiber post: Evaluation of surface characteristic and bonded area of fiber post with resin cement

Objective: Fiber post is cemented to a root canal to restore coronal tooth structure. This research aims to evaluate the effect of ultraviolet (UV) irradiation on bond strength of fiber post with resin cement. Materials and Methods: A total of 40 of the two types of fiber posts, namely, FRC Prostec (FRC) and Fiber KOR (KOR), were used for the experiment. UV irradiation was applied on top of the fiber post surface for 0, 15, 20, and 30 min. The irradiated surface of the fiber posts (n = 5) were immediately bonded with resin cement (Rely X U200) after UV irradiation. Shear bond strength (SBS) MPa was measured, and the dislodged area of post surfaces was examined with scanning electron microscopes. Changes in surface roughness (Ra) of the FRC group after UV irradiation were observed (n = 3) using atomic force microscopy. Data of SBS were statistically analyzed using one-way analysis of variance, followed by multiple comparisons (P < 0.05). Results: SBS was significantly higher for 20 min of UV irradiation of the FRC group while significantly higher SBS was observed with 15 min of UV irradiation of the KOR group. Resin cement was more evident (cohesive failure) on the dislodged post surface of the UV treated groups compared with the control. The surface roughness of the FRC post was Ra = 175.1 nm and Ra = 929.2 nm for the control and the 20 min group, respectively. Conclusions: Higher surface roughness of the UV irradiated group indicated formation of mechanical retention on the fiber post surface. Evidence of cohesive failure was observed which indicated higher SBS of fiber post with the UV irradiated group.
Symmetry-based indexing of image databases

The use of shape as a cue for indexing in pictorial databases has been traditionally based on global invariant statistics and deformable templates, on the one hand, and local edge correlation on the other. This paper proposes an intermediate approach based on a characterization of the symmetry in edge maps. The use of symmetry matching as a joint correlation measure between pairs of edge elements further constrains the comparison of edge maps. In addition, a natural organization of groups of symmetry into a hierarchy leads to a graph-based representation of relational structure of components of shape that allows for deformations by changing attributes of this relational graph. A graduate assignment graph matching algorithm is used to match symmetry structure in images to stored prototypes or sketches. The results of matching sketches and grey-scale images against a small database consisting of a variety of fish, planes, tools, etc., are depicted.
Men's behavior toward women after viewing sexually-explicit films: degradation makes a difference

Past research indicates that short-term exposure to nonviolent sexual media stimuli can produce cognitive changes in men which, in turn, can affect their behavior toward women. This study explored differences among these behavioral effects based upon sexual degradation in film content and male viewers' gender schematicity, as an extension of the study of cognitive effects reported in Jansma, Linz, Mulac, and Imrich (1997). Seventy-one men viewed one of three films: (a) sexually-explicit and degrading to women, (b) sexually-explicit but non-degrading, or (c) non-sexual. The men then interacted with women in problem-solving dyads that were recorded on videotape. Men who viewed either sexually-explicit film displayed more dominance and anxiety than did the men who viewed the non-sexual film. This was true, however, for only the two-thirds who were non sex-typed (BSRI, Bem, 1974). Sex-typed men's behavior was consistent across sexual versus non-sexual film conditions. In addition, men who viewed the degrading sexual film displayed less anxiety, but more dominance, than men who watched the non-degrading sexual film. Women's behavior failed to distinguish which of the three films their partners had viewed, but was positively correlated with most of their partner's discriminating behavior. Results of men's viewing sexual or degrading sexual material are discussed in terms of negative social implications for women in the context of everyday male-female interactions.
On Cryptographic Chained Puzzles

Cryptographic puzzles provide an elegant solution in combating denial of services attacks. In this paper we introduce the concept of chained puzzles and we define two kinds of chained puzzles: linearly chained puzzles and randomly chained puzzles. These construnstions prove to be very useful in some scenarios, from which the more general is in which a client may choose to solve only some of the puzzles that were sent by the server and gain resources from a server according to the amount of puzzles that he solved.
Human-Readable Real-Time Classifications of Malicious Executables

Shafiq et al. (2009a) propose a non–signature-based technique for detecting malware which applies data mining techniques to features extracted from executable files. Their technique has a high level of accuracy, a low false positive rate, and a speed on par with commercial anti-virus products. One portion of their technique uses a multi-layer perceptron as a classifier, which provides little insight into the reasons for classification. Our experience is that network security analysts prefer tools which provide human-comprehensible reasons for a classification, rather than operating as “black boxes”. We therefore build on the results of Shafiq et al. by demonstrating a technique which uses decision trees to distinguish packed from non-packed files, producing a classification diagram which can be understood by analysts. We show that the resulting detector still provides high accuracy and classifies files rapidly.
Mobile Access to the Intranet: Web Content Management for PDAs

Although the wealth of information provided by the World-Wide Web is of great value, most of its content is designed for desktop computers. In days when people are becoming increasingly mobile, and hence utilises devises with much smaller screens, much of this information in reality becomes inaccessible. The same is true also for organisational intranets. However, the content management systems (CMS) being used within organisations offer new and unexplored possibilities to present information. In this paper, we describe a CMSbased approach to visualise web information in a PDA, show the benefits of such an approach, and share the lessons learned from deploying this technique in an organisational context.
CD2 Promotes Human Natural Killer Cell Membrane Nanotube Formation

Membrane nanotubes are thin membranous projections that physically connect two cells. While nanotubes have been studied in human natural killer (NK) cells and are implicated in aiding NK cell cytotoxic function, requirements for their formation to susceptible target cells remain incompletely understood. Here we demonstrate that the CD2-CD58/48 receptor-ligand interaction promotes and is required for nanotube formation in human NK cells. In the CD2− NK cell line YTS, a stable CD2 expression variant enabled effective nanotube formation, and was associated with better cytotoxic function. Importantly, only interactions between an NK cell and a susceptible target cell were associated with multiple nanotubes and the number of nanotubes was inversely correlated with their length. Quantitative live cell fluorescence microscopy of CD2 nanotubes revealed time-dependent enrichment and localization of CD2 to the nanotube tip, and blocking CD2 receptor-ligand interactions prevented nanotube formation. Increased nanotube formation was not simply a feature of receptor-ligand pairing, as a KIR-MHC interaction in the same cell line system failed to promote nanotube formation. Additionally, blocking LFA-1-ICAM and 2B4-CD48 receptor-ligand interactions failed to inhibit nanotube formation. Thus only specific receptor-ligand pairs promote nanotubes. CD2 also promoted nanotube formation in ex vivo NK cells suggesting that CD2 plays a crucial role in the generation of nanotubes between an NK cell and its target.
The Design and Research of Switching Power Amplifier Used on Magnetic Suspension Support

This paper focuses on the switching power amplifier of magnetic suspension support. The principle of magnetic suspension support was described. Due to the particularity that the load of magnetic suspension support is inductive, the response speed, efficiency and stability should be considered when the switching power amplifier is designed. In the power amplifier, PI circuit can make feedback current follow the given signal in time. In this paper, the amplifier adopts pulse width modulation (PWM) control strategy. The design of PI circuit, PWM circuit as well as the driving circuit were presented in the paper. After completing the designs of all parts, we choose MULTISIM as simulation software, which can establish an accurate circuit model. The simulation results show that the switching power amplifier designed in this paper has bigger bandwidth and less distortion and it can respond timely.
The Harper–Hofstadter Hamiltonian and conical diffraction in photonic lattices with grating assisted tunneling

We propose the realization of a grating assisted tunneling scheme for tunable synthetic magnetic fields in optically induced one- and two-dimensional dielectric photonic lattices. As a signature of the synthetic magnetic fields, we demonstrate conical diffraction patterns in particular realization of these lattices, which possess Dirac points in k-space. We compare the light propagation in these realistic (continuous) systems with the evolution in discrete models representing the Harper–Hofstadter Hamiltonian, and obtain excellent agreement.
A Decentralized Voting Algorithm for Increasing Dependability in Distributed Systems

Replication and majority voting are well-known and widely-used methods for achieving fault-tolerance in distributed systems. An open area of investigation is coordinating the voting in a secure manner, so as to withstand malicious attacks. The Timed-Buffer Distributed Voting Algorithm (TB-DVA), a secure distributed voting protocol, is introduced for this purpose. It is contrasted with several other distributed voting schemes in order to show its unique contribution for both fault-tolerance and security, which are essential ingredients for system dependability.
Pose Invariant Face Recognition Using Neuro-Biologically Inspired Features

A face recognition algorithm using biologically inspired C2 standard model features is proposed. The C2 feature extraction system, which is based on the standard model of the ventral stream of visual cortex, is modified for the extraction of facial features. The S2 units in the learning stage are tuned to frontal and profile views of the faces to provide pose invariant recognition. A new learning function is utilized to extract discriminative facial features. The spatial invariance is limited both in the local and global pooling stages. The reduced spatial invariance in the local pooling preserves the minute shape and texture details of the facial components, whereas that in the global pooling stage preserves the component location information. The faces are classified using a support vector machines classifier with linear kernel. The proposed algorithm is tested using two face datasets (MIT-CBCL, FEI) with wide variations in profiles, and compared with existing algorithms (the original C2 feature extraction algorithm and MPCALDA algorithm). The experimental results provide evidence of the better performance of the proposed approach for pose invariant face recognition, by at least 6.5%.
Technical Efficiency and Technological Change in Australian Building Societies

In this study the nature and extent of efficiency and productivity growth in deposit-taking institutions is investigated using nonparametric frontier techniques. Employing Malmquist indices, productivity growth is decomposed into technical efficiency change and technological change for a sample of Australian building societies. The results indicate that most building societies experienced productivity gain in the past several years, and this was largely the result of technological progress rather than efficiency improvements. That productivity growth which did occur due to an increase in efficiency over the period tended to be the result of improvements in scale efficiency, whilst efficiency gain was most pronounced in building societies with a high ratio of net interest income and non-interest income to total assets, low operating expense ratios, and relatively high expenditures on marketing and promotion.
The penumbra of learning: A statistical theory of synaptic tagging and capture

Learning in humans and animals is accompanied by a penumbra: Learning one task benefits from learning an unrelated task shortly before or after. At the cellular level, the penumbra of learning appears when weak potentiation of one synapse is amplified by strong potentiation of another synapse on the same neuron during a critical time window. Weak potentiation sets a molecular tag that enables the synapse to capture plasticity-related proteins synthesized in response to strong potentiation at another synapse. This paper describes a computational model which formalizes synaptic tagging and capture in terms of statistical learning mech- anisms. According to this model, synaptic strength encodes a probabilistic inference about the dynamically changing association between pre- and post-synaptic firing rates. The rate of change is itself inferred, coupling together different synapses on the same neuron. When the inputs to one synapse change rapidly, the inferred rate of change increases, amplifying learning at other synapses.
Initial Performance of Greek Ipos, Underwriter's Reputation and Oversubscription

This paper provides additional international evidence on the IPOs by examining the initial performance and two main determinants of short-run underpricing of 169 IPOs listed on the Athens Stock Exchange (ASE) over the period 1997-2002. The initial performance of the IPOs is measured by calculated two formulas: the raw returns and the excess or adjusted returns of the first, fifth and twenty first day respectively. Furthermore, we use a proxy to rank the underwriters’ prestige along with the times of oversubscription, which are introduced as explanatory variables in our model. The results of the analysis provide evidence of significant underpricing. Furthermore, the cross sectional analysis on the determinants of the IPOs shows that both the underwriters’ prestige and the times of oversubscription significantly affect the underpricing level of the IPOs over the most important and “hot” period for the Greek emerging stock market since its establishment, in terms of growth rates, acceleration of the going public process and volatility of market and stock returns.
Pollutant's Dispersion in the Atmosphere. Parallel Models and Applications

The following article contains information about modeling of pollutants dispersion systems in the atmosphere. It also describes main types of pollutants, emission points and analysis of typical atmosphere pollutant dispersion models. It shows a way of using computer cluster systems in modeling process and proper programming libraries for parallel computing. Finally it presents a possibility of environment's protection method during the emission points' location planning with calculation of minimal destructive influence on a specified area (for example with definite restrictions of air pollution level).
Governments as human capital providers: A rationale for strong government support of broad higher education access

Purpose – The purpose of this paper is to provide an analysis of the case for governmental support of higher education access to further national competitiveness.Design/methodology/approach – A review of previous literature is used to examine different academic disciplines that impact the relationship between higher education access and national competitiveness. These bodies of knowledge are used to synthesize a rationale for impacting competitiveness through educational policy.Findings – A coherent argument can be made that is strongly in support of governmental provision of relatively high levels of access to higher education.Research limitations/implications – The recommendations are general. A specific cost‐benefit analysis of educational policies is beyond the scope of this paper.Practical implications – This paper equips readers to explain why higher education access influences national competitiveness. While this point seems obvious to many who work in higher education, the connection is seldom mad.