Showing papers by "University of Cyprus published in 2006"

Stakeholder Pressures And Environmental Performance

Abstract: We examine the connection between the internal heterogeneity of stakeholder groups and the resource dependence dynamics characterizing their relationships with firms. Empirically, we test how this ...

Search for neutral MSSM Higgs bosons at LEP

Abstract: The four LEP collaborations, ALEPH, DELPHI, L3 and OPAL, have searched for the neutral Higgs bosons which are predicted by the Minimal Supersymmetric standard model (MSSM). The data of the four collaborations are statistically combined and examined for their consistency with the background hypothesis and with a possible Higgs boson signal. The combined LEP data show no significant excess of events which would indicate the production of Higgs bosons. The search results are used to set upper bounds on the cross-sections of various Higgs-like event topologies. The results are interpreted within the MSSM in a number of “benchmark” models, including CP-conserving and CP-violating scenarios. These interpretations lead in all cases to large exclusions in the MSSM parameter space. Absolute limits are set on the parameter cosβ and, in some scenarios, on the masses of neutral Higgs bosons.

Strategy fit and performance consequences of international marketing standardization

Abstract: This study addresses a long-standing debate in the literature regarding the appropriateness and performance consequences of marketing strategy standardization vs. adaptation. Much of the relevant literature represents the headquarters' viewpoint and broadly assesses antecedents of standardization or adaptation across widely varying markets. Using strategic fit as the theoretical platform for analysis, the study investigates international marketing strategy for a specific product or line within subsidiaries of U.S., Japanese, and German multinational corporations (MNCs) operating in the U.K. The results indicate that degree of strategy standardization is significantly related to similarity between markets with respect to regulatory environments, technological intensity and velocity, customs and traditions, customer characteristics, a product's stage in its life cycle, and competitive intensity. On the critical question of performance consequences, the findings suggest that superior performance results from strategy standardization only to the extent that there is fit or coalignment between the MNC's environmental context and its international marketing strategy choice. Copyright © 2006 John Wiley & Sons, Ltd.

Bactericidal Action of the Reactive Species Produced by Gas-Discharge Nonthermal Plasma at Atmospheric Pressure: A Review

Abstract: Biological decontamination using a nonthermal gas discharge at atmospheric pressure in air is the subject of significant research effort at this time. The mechanism for bacterial deactivation undergoes a lot of speculation, particularly with regard to the role of ions and reactive gas species. Two mechanisms have been proposed: electrostatic disruption of cell membranes and lethal oxidation of membrane or cytoplasmic components. Results show that death is accompanied by cell lysis and fragmentation in Gram-negative bacteria but not Gram-positive species, although cytoplasmic leakage is generally observed. Gas discharges can be a source of charged particles, ions, reactive gas species, radicals, and radiation (ultraviolet, infrared, and visible), many of which have documented biocidal properties. The individual roles played by these in decontamination are not well understood or quantified. However, the reactions of some species with biomolecules are documented otherwise in the literature. Oxidative stress is relatively well studied, and it is likely that exposure to gas discharges in air causes extreme oxidative challenge. In this paper, a review is presented of the major reactive species generated by nonthermal plasma at atmospheric pressure and the known reactions of these with biological molecules. Understanding these mechanisms becomes increasingly important as plasma-based decontamination and sterilization devices come closer to a wide-scale application in medical, healthcare, food processing, and air purification applications. Approaches are proposed to elucidate the relative importance of reactive species

An analysis of the Revised Olweus Bully/Victim Questionnaire using the Rasch measurement model.

Abstract: BACKGROUND: Bullying is a problem in schools in many countries. There would be a benefit in the availability of a psychometrically sound instrument for its measurement, for use by teachers and researchers. The Olweus Bully/Victim Questionnaire has been used in a number of studies but comprehensive evidence on its validity is not available. AIMS: To examine the conceptual design, construct validity and reliability of the Revised Olweus Bully/Victim Questionnaire (OBVQ) and to provide further evidence on the prevalence of different forms of bullying behaviour. SAMPLE: All 335 pupils (160 [47.8%] girls; 175 [52.2%]) boys, mean age 11.9 years [range 11.2-12.8 years]), in 21 classes of a stratified sample of 7 Greek Cypriot primary schools. METHOD: The OBVQ was administered to the sample. Separate scales were created comprising (a) the items of the questionnaire concerning the extent to which pupils are being victimized; and (b) those concerning the extent to which pupils express bullying behaviour. Using the Rasch model, both scales were analysed for reliability, fit to the model, meaning, and validity. Both scales were also analysed separately for each of two sample groups (i.e. boys and girls) to test their invariance. RESULTS: Analysis of the data revealed that the instrument has satisfactory psychometric properties; namely, construct validity and reliability. The conceptual design of the instrument was also confirmed. The analysis leads also to suggestions for improving the targeting of items against student measures. Support was also provided for the relative prevalence of verbal, indirect and physical bullying. As in other countries, Cypriot boys used and experienced more bullying than girls, and boys used more physical and less indirect forms of bullying than girls. CONCLUSIONS: The OBVQ is a psychometrically sound instrument that measures two separate aspects of bullying, and whose use is supported for international studies of bullying in different countries. However, improvements to the questionnaire were also identified to provide increased usefulness to teachers tackling this significant problem facing schools in many countries. Language: en

Direct Estimation of the Seismic Demand and Capacity of Oscillators with Multi-Linear Static Pushovers through IDA ‡

Abstract: SUMMARY SPO2IDA is introduced, a software tool that is capable of recreating the seismic behavior of oscillators with complex quadrilinear backbones. It provides a direct connection between the Static Pushover (SPO) curve and the results of Incremental Dynamic Analysis (IDA), a computer-intensive procedure that offers thorough demand and capacity prediction capability by using a series of nonlinear dynamic analyses under a suitably scaled suite of ground motion records. To achieve this, the seismic behavior of numerous single-degree-of-freedom (SDOF) systems is investigated through IDA. The oscillators have a wide range of periods and feature pinching hysteresis with backbones ranging from simple bilinear to complex quadrilinear with an elastic, a hardening and a negativestiffness segment plus a final residual plateau that terminates with a drop to zero strength. An efficient method is introduced to treat the backbone shape by summarizing the analysis results into the 16%, 50% and 84% fractile IDA curves, reducing them to a few shape parameters and finding simpler backbones that reproduce the IDA curves of complex ones. Thus, vast economies are realized while important intuition is gained on the role of the backbone shape to the seismic performance. The final product is SPO2IDA, an accurate, spreadsheet-level tool for Performance-Based Earthquake Engineering that can rapidly estimate demands and limit-state capacities, strength reduction R-factors and inelastic displacement ratios for any SDOF system with such a quadrilinear SPO curve. Copyright c ∞ 2005 John Wiley & Sons, Ltd.

Critical analysis of the current approaches to modelling educational effectiveness: The importance of establishing a dynamic model

Abstract: Researchers in the area of educational effectiveness should attempt to develop a new theoretical framework. A critical analysis of the current models of educational effectiveness research is provided and reveals that a dynamic model of effectiveness must: (a) be multilevel in nature, (b) be based on the assumption that the relation of some effectiveness factors with achievement may be curvilinear, (c) illustrate the dimensions upon which the measurement of each effectiveness factor should be based, and (d) define relations among the effectiveness factors. In principle, each factor that refers to the classroom, school, and system, can be measured by taking into account five dimensions: frequency, focus, stage, quality, and differentiation. Examples of measuring effectiveness factors operating at different levels using these 5 dimensions are given. More attention in describing in detail factors associated with teacher behaviour in the classroom is given, since this is seen as the starting point for the deve...

Positive real synthesis using matrix inequalities for mechanical networks: application to vehicle suspension

Abstract: This paper presents a procedure for the synthesis of positive real controllers based on matrix inequalities. Problems with H/sub 2/ and H/sub /spl infin// cost are considered and the resulting bilinear matrix inequality problems are solved using local, iterative algorithms. The procedure is applied to the synthesis of passive suspensions for the optimization of certain performance measures for a quarter-car model. The characterization of the positive real constraint using matrix inequalities and the use of a new mechanical element called the inerter, permits the optimization over the entire class of positive real admittances and the realization of the resulting admittance using passive elements. The optimization results are compared with previous results obtained using optimization over fixed-structure admittances. The proposed method can reproduce the previous results and achieve better results in certain cases. Results of the experimental testing of a mechanical network involving an inerter are presented.

Optimal deployment of large wireless sensor networks

Abstract: A spatially distributed set of sources is creating data that must be delivered to a spatially distributed set of sinks. A network of wireless nodes is responsible for sensing the data at the sources, transporting them over a wireless channel, and delivering them to the sinks. The problem is to find the optimal placement of nodes, so that a minimum number of them is needed. The critical assumption is made that the network is massively dense, i.e., there are so many sources, sinks, and wireless nodes, that it does not make sense to discuss in terms of microscopic parameters, such as their individual placements, but rather in terms of macroscopic parameters, such as their spatial densities. Assuming a particular interference-limited, capacity-achieving physical layer, and specifying that nodes only need to transport the data (and not to sense them at the sources, or deliver them at the sinks once their location is reached), the optimal node placement induces a traffic flow that is identical to the electrostatic field created if the sources and sinks are replaced by a corresponding distribution of positive and negative charges. Assuming a general model for the physical layer, and specifying that nodes must not only transport the data, but also sense them at the sources and deliver them at the sinks, the optimal placement of nodes is given by a scalar nonlinear partial differential equation found by calculus of variations techniques. The proposed formulation and derived equations can help in the design of large wireless sensor networks that are deployed in the most efficient manner, not only avoiding the formation of bottlenecks, but also striking the optimal balance between reducing congestion and having the data packets follow short routes.

A functional wavelet–kernel approach for time series prediction

Abstract: Summary. We consider the prediction problem of a time series on a whole time interval in terms of its past. The approach that we adopt is based on functional kernel nonparametric regression estimation techniques where observations are discrete recordings of segments of an underlying stochastic process considered as curves. These curves are assumed to lie within the space of continuous functions, and the discretized time series data set consists of a relatively small, compared with the number of segments, number of measurements made at regular times. We estimate conditional expectations by using appropriate wavelet decompositions of the segmented sample paths. A notion of similarity, based on wavelet decompositions, is used to calibrate the prediction. Asymptotic properties when the number of segments grows to 1 are investigated under mild conditions, and a nonparametric resampling procedure is used to generate, in a flexible way, valid asymptotic pointwise prediction intervals for the trajectories predicted. We illustrate the usefulness of the proposed functional wavelet–kernel methodology in finite sample situations by means of a simulated example and two real life data sets, and we compare the resulting predictions with those obtained by three other methods in the literature, in particular with a smoothing spline method, with an exponential smoothing procedure and with a seasonal autoregressive integrated moving average model.

Economic development and the return to human capital: a smooth coefficient semiparametric approach

Abstract: This paper investigates the impact of human capital on the process of economic growth by allowing the contribution of traditional inputs (capital and labour) as well as that of human capital to vary both across countries and time. The former is accomplished by constructing an index of TFP growth for traditional inputs, while the latter through semiparametric methods. We derive estimates of the output elasticity and social return to human capital for 51 countries at various stages of economic development. Copyright © 2005 John Wiley & Sons, Ltd.

A Family of 3D Coordination Polymers Composed of Mn19 Magnetic Units

Abstract: The current intense interest in polynuclear clusters stems not only from their aesthetically pleasing structures, magnetic interactions, and magnetostructural correlations, but also from the discovery that some function as nanoscale magnetic particles, or single-molecule magnets (SMMs). Below their blocking temperature (TB), such molecules behave as magnets and exhibit hysteresis in scans of magnetization versus dc field. This behavior results from the combination of a large ground spin state (S) with a large and negative (easy-axis type) magnetoanisotropy. SMMs have several potential applications, including high-density information storage, in which each bit of information is stored as the magnetization orientation of an individual molecule, and quantum computation, in which the molecules can serve as qubits. Although there are many known species displaying SMM behavior, most of which are manganese–carboxylate complexes, there is a continuing need for new SMMs. One of the most successful synthetic approaches to new polynuclear clusters involves the use of chelating ligands containing alkoxide functions, since these are good bridging groups and, thus, favor the formation of polynuclear products. Recently, we have been investigating the use of 1,3propanediol (H2pd) and 2-methyl-1,3-propanediol (H2mpd) in manganese–carboxylate chemistry. Herein, we report the syntheses, crystal structures, and magnetic properties of two new 3D coordination polymers based on [Mn19Na(m4-O)9(m3-

The Effect of the Presence of Water on the Durability of Bond between CFRP and Concrete

Abstract: This research assesses the effects of the presence of water during the carbon fiber reinforced polymer (CFRP) application and after the CFRP cure on the bond between the CFRP and the concrete. Modified double cantilever beam (MDCB) specimens are used to determine the interfacial energy release rate, G, of the CFRP—concrete bond. A CFRP fabric is applied to the specimens with three different initial levels of water/moisture presence. Other specimens, with a CFRP fabric applied in dry conditions and allowed to cure, are conditioned in a saturated environment for different lengths of time. The test results indicate that the presence of water during the CFRP application decreases the bond quality significantly and most of the resulting failures are adhesive failures along the primer/concrete interface. The use of a specially formulated primer results in a slightly higher bond capacity but the same undesirable failure. High quality CFRP applications, conditioned in a saturated environment for a relatively shor...

Quality evaluation of ultrasound imaging in the carotid artery based on normalization and speckle reduction filtering.

Abstract: Image quality is important when evaluating ultrasound images of the carotid for the assessment of the degree of atherosclerotic disease, or when transferring images through a telemedicine channel, and/or in other image processing tasks. The objective of this study was to investigate the usefulness of image quality evaluation based on image quality metrics and visual perception, in ultrasound imaging of the carotid artery after normalization and speckle reduction filtering. Image quality was evaluated based on statistical and texture features, image quality evaluation metrics, and visual perception evaluation made by two experts. These were computed on 80 longitudinal ultrasound images of the carotid bifurcation recorded from two different ultrasound scanners, the HDI ATL-3000 and the HDI ATL-5000 scanner, before (NF) and after (DS) speckle reduction filtering, after normalization (N), and after normalization and speckle reduction filtering (NDS). The results of this study showed that: (1) the normalized speckle reduction, NDS, images were rated visually better on both scanners; (2) the NDS images showed better statistical and texture analysis results on both scanners; (3) better image quality evaluation results were obtained between the original (NF) and normalized (N) images, i.e. NF-N, for both scanners, followed by the NF-DS images for the ATL HDI-5000 scanner and the NF-DS on the HDI ATL-3000 scanner; (4) the ATL HDI-5000 scanner images have considerable higher entropy than the ATL HDI-3000 scanner and thus more information content. However, based on the visual evaluation by the two experts, both scanners were rated similarly. The above findings are also in agreement with the visual perception evaluation, carried out by the two vascular experts. The results of this study showed that ultrasound image normalization and speckle reduction filtering are important preprocessing steps favoring image quality, and should be further investigated.

An integrated model of the behavioural dimensions of industrial buyer‐seller relationships

Abstract: Purpose – Research on the behavioural aspects of buyer‐seller relationships, although sizeable, is too heterogeneous and fragmented to yield complete and conclusive insights as to the inter‐relationships of the basic parameters involved. This article attempts to put together extant knowledge on the subject under an integrated conceptual model comprising ten key behavioural constructs.Design/methodology/approach – A total of 24 theoretically‐anchored hypotheses are developed, indicating possible positive or negative associations among the constructs of the model. Based on input received from 122 producers of industrial goods, the proposed model is empirically tested using structural equation modelling.Findings – Of the hypothesized associations examined, 16 were found to be statistically significant and in the right direction, two were significant but in the opposite direction, while the remaining six were not validated. The results confirm most of the findings of previous research on the subject, while so...

Evidence for diquarks in lattice QCD.

Abstract: Diquarks may play an important role in hadron spectroscopy, baryon decays, and color superconductivity. We investigate the existence of diquark correlations in lattice QCD by considering systematically all the lowest energy diquark channels in a color gauge-invariant setup. We measure mass differences between the various channels and show that the positive parity scalar diquark is the lightest. Quark-quark correlations inside the diquark are clearly seen in this channel, and yield a diquark size of O(1) fm.

The international system for teacher observation and feedback: evolution of an international study of teacher effectiviness constructs.

Abstract: This article presents information on 2 international educational effectiveness studies, one completed and the other ongoing. The 2nd study is, to a large degree, a reaction to a methodological problem encountered in the 1st study, the lack of an internationally valid instrument measuring teacher effectiveness. This article presents 4 reasons for conducting the 2nd study (International System for Teacher Observation and Feedback (ISTOF)) and then details the overall work plan for ISTOF-I (2004 – 2006) and ISTOF-II (2006 – 2007). The sample of 20 fully participating country teams in ISTOF is very diverse with representatives from nearly all geographic areas of the world (North and South America, Europe, Africa, Asia), many of which have never participated in teacher or school effectiveness research. This article summarizes progress made on the development of the ISTOF protocol, including the generation of components and indicators of teacher effectiveness. In many ways, the study is already a success, due t...

Application of abductive ILP to learning metabolic network inhibition from temporal data

Abstract: In this paper we use a logic-based representation and a combination of Abduc- tion and Induction to model inhibition in metabolic networks In general, the integration of abduction and induction is required when the following two conditions hold Firstly, the given background knowledge is incomplete Secondly, the problem must require the learning of general rules in the circumstance in which the hypothesis language is disjoint from the observation language Both these conditions hold in the application considered in this paper Inhibition is very important from the therapeutic point of view since many substances de- signed to be used as drugs can have an inhibitory effect on other enzymes Any system able to predict the inhibitory effect of substances on the metabolic network would therefore be very useful in assessing the potential harmful side-effects of drugs In modelling the phenomenon of inhibition in metabolic networks, background knowledge is used which describes the net- work topology and functional classes of inhibitors and enzymes This background knowledge, which represents the present state of understanding, is incomplete In order to overcome this incompleteness hypotheses are considered which consist of a mixture of specific inhibitions of enzymes (ground facts) together with general (non-ground) rules which predict classes of enzymes likely to be inhibited by the toxin The foreground examples are derived from in vivo experiments involving NMR analysis of time-varying metabolite concentrations in

Divided Cyprus : modernity, history, and an island in conflict

Abstract: Contents Acknowledgments Introduction: Modernity, History, and Conflict in Divided Cyprus: An Overview Yiannis Papadakis, Nicos Peristianis, and Gisela Welz 1. Transforming Lives: Process and Person in Cypriot Modernity Michael Herzfeld 2. On the Condition of Postcoloniality in Cyprus Rebecca Bryant 3. Disclosure and Censorship in Divided Cyprus: Toward an Anthropology of Ethnic Autism Yiannis Papadakis 4. De-Ethnicizing the Ethnography of Cyprus: Political and Social Conflict between Turkish Cypriots and Settlers from Turkey Yael Navaro-Yashin 5. Cypriot Nationalism, Dual Identity, and Politics Nicos Peristianis 6. Children Constructing Ethnic Identities in Cyprus Spyros Spyrou 7. "Contested Natures": An Environmental Conflict in Cyprus Gisela Welz 8. Gardens and the Nature of Rootedness in Cyprus Anne Jepson 9. Researching Society and Culture in Cyprus: Displacements, Hybridities, and Dialogical Frameworks Floya Anthias 10. Recognition and Emotion: Exhumations of Missing Persons in Cyprus Paul Sant Cassia 11. Postscript: Reflections on an Anthropology of Cyprus Vassos Argyrou List of Contributors Index

Full-Scale Experimental Investigation of Repair of Reinforced Concrete Interstate Bridge Using CFRP Materials

Abstract: An experimental study is presented of the behavior of eight reinforced concrete bridge girders taken from a decommissioned Interstate bridge and retrofitted with three different carbon-fiber-reinforced polymer (CFRP) systems. Specimens were subjected to monotonic loading to failure with and without significant fatigue conditioning. Experimental observations indicated that intermediate crack-induced debonding was the dominant failure mode for monotonically loaded beams and that degradation of the CFRP-to-concrete interface was caused by fatigue conditioning. Conventional adhesive applied and near-surface mounted (NSM) CFRP systems behaved well under monotonic loads, with the NSM system exhibiting significantly greater ductility. Powder actuated fastener applied retrofit was observed to be less efficient, requiring a relative slip of the CFRP in order to engage the shear transfer mechanism of the fasteners. The application of current accepted design guidelines for FRP retrofit indicated that guidelines aimed at mitigating debonding failure appear to be appropriately conservative under monotonic loading conditions; however, a significant additional reduction in CFRP strain limits is required to account for even small levels of fatigue loading.

Amphiphilic polymethacrylate model co-networks : Synthesis by RAFT radical polymerization and characterization of the swelling behavior

Abstract: Reversible addition−fragmentation chain transfer (RAFT) controlled radical polymerization was employed, for the first time, to prepare well-defined (model) amphiphilic polymer co-networks based on ...