Gender swapping and socialising in cyberspace: an exploratory study

Massively multiplayer online role-playing games (MMORPGs) are one of the most interesting innovations in the area of online computer gaming. Given the relative lack of research in the area, the main aims of the study were to examine (a) the impact of online gaming (e.g., typical playing behavior) in the lives of online gamers, (b) the effect of online socializing in the lives of gamers, and (c) why people engage in gender swapping. A self-selecting sample of 119 online gamers ranging from 18 to 69 years (M = 28.5 years) completed a questionnaire. The results showed that just over one in five gamers (21%) said they preferred socializing online to offline. Significantly more male gamers than female gamers said that they found it easier to converse online than offline. It was also found that 57% of gamers had engaged in gender swapping, and it is suggested that the online female persona has a number of positive social attributes in a male-oriented environment

Comments on 'A high resolution quadratic time-frequency distribution for multicomponent signals analysis'

For original paper see Barkat and Boashash (IEEE Trans. Signal Processing, vol.49, p.2232-9, 2001). It is shown that the time-frequency distribution (TFD) proposed in the above paper is not well defined in the ordinary sense for power signals, including the single-tone sinusoid, and it needs the introduction of generalized functions and transforms. It is also shown that the proposed TFD does not satisfy the conditions cited by the authors of the paper to justify the claim that it has the instantaneous frequency property

Frequency estimation of mono-and multicomponent FM signal using the T-distributions

In a recent work we have proposed a subclass of Cohen's Class of quadratic time-frequency distributions (TFD's), the T-class of distributions with time-only Doppler-lag kernels to provide high-resolution and considerable cross-terms reduction for FM signals. In this work we investigate the instantaneous frequency (IF) properties of two members of this class: the hyperbolic and the exponential T-distributions in the presence of Gaussian noise. Both mono- and multi-component FM signals will be considered, with various modulation coefficients. A comparison with two well-known TFD's, Wigner-Ville and Choi-Williams distributions, is presented for performance evaluation

Online gaming and addiction: a psychosocial investigation using mixed methods

Online virtual worlds known as Massively Multiplayer Online Role-Playing Games (MMORPGs) have gained increased popularity over the last decade. MMORPGs provide a sophisticated environment that enables complete immersion within the virtual world to the extent that it may become an alternative reality to its users. Some researchers have suggested that online gaming addiction is growing in prevalence among adolescents and adult gamers. It has been proposed that research is needed to establish the incidence and prevalence of MMORPG addiction. The aim of this body of research was to examine the impact of MMORPGs (psychologically and socially) on peoples' lives for the purpose of providing an empirical research base on which future research in the area can build. Using a mixed methods approach for data collection and analysis, an online scoping study, interview study and two questionnaire studies were conducted. The thesis provides a detailed conceptualisation of the psychological processes involved in MMORPG playing. The thesis was directed by previous research into video games, online gaming and addiction which provided a substantive picture of the psychosocial effects of online gaming. The findings showed that there were both positive and negative effects associated with online gaming; gamers used MMORPGs to alleviate negative feelings and to meet new people, learn about new cultures, and build friendships. Gamers also provided detailed descriptions of personal problems that had arisen due to playing MMORPGs. A small percentage of gamers (3.6%) were classified as addicted to MMORPGs, these gamers may find it difficult to control their game playing behaviour. However, there are still gaps in our knowledge of MMORPGs. Overall, the research has shown that the psychology of MMORPGs is an important topic that requires further in-depth investigation. The present research has revealed valuable information about the impact of MMORPGs on the lives of gamers that can be built upon by other researchers. Implications of the findings regarding excessive playing and addiction to MMORPGs, and social responsibility were discussed, and recommendations for future research studies were proposed

Metal-organic Framework (MOFs) Derived Nanocomposites: Synthesis and Applications in Photocatalysis

Metal-organic frameworks (MOFs) are exceptionally porous coordination polymers forming highly crystalline reticular networks via the coordination bonds between organic ligands and inorganic metal clusters. In the past 10 years, MOFs have been proved to be excellent rationally designed precursors and sacrificial templates to derive metal compounds, metal compounds/carbon composites, porous carbons and related nanostructures. The inherited morphologies, adjustable structural and textural properties, in-situ modifiable physicochemical and semiconducting properties make MOFs derived composites excellent nanomaterials for a wide variety of applications in chemistry, physics, electronics and medical sciences. This thesis demonstrates the synthesis of selected Zn-MOFs and Ti-MOFs and their derived functionalised nanocomposites for applications in environment and energy. Briefly, this thesis systematically presents the following research findings: The role of pyrolysis temperature and gaseous atmosphere in Zn-MOF derived composites was studied. Homogeneously dispersed crystalline ZnO nanoparticles embedded in a porous carbon matrix were synthesised via simple one-step carbonisation of MOF-5 at 800 °C and 1000 °C in air, argon and water vapour atmospheres. The resulting carbon doped ZnO, ZnO/C or porous carbon, decorated with hydrophilic functional groups retains the inherited cubic morphology of the precursor MOF-5. Built on the finding of the optimal synthesis conditions for best performing ZnO/C composites, a comparative study of 3 different Zn-MOFs including MOF-5, MOF-74 and ZIF-8 derived ZnO/C nanocomposites was carried out to further understand the structure-property-application relationships. The photocatalytic performance of these derived composites was also evaluated for photodegradation of organic dye pollutants and photocatalytic H2 evolution reaction. Moreover, an in-depth in-situ study was carried out to understand the pyrolytic conversion mechanism of Ti-MOF precursors into the desired TiO2/C nanocomposites. The ¬in-situ TGA-MS and in-situ STEM/EDX combined with other characterisation techniques were employed to investigate the evolution of the structural, physicochemical, textural and morphological properties of the NH2-MIL-125(Ti) derived nanocomposites. Based on the understanding of the thermal decomposition mechanism of NH2-MIL-125(Ti), Cu species were loaded into NH2-MIL-125(Ti) via the post-synthetic method to obtain bimetallic NH2-MIL-125(Ti/Cu). The effect of pyrolysis temperature on the thermal decomposition of NH2-MIL-125(Ti/Cu) under water vapour atmosphere and the subsequent in-situ formation of the p-n heterojunction between TiO2 and CuxO nanoparticles were investigated, and their performance in photocatalytic H2 evolution from water splitting was evaluated.Engineering and Physical Sciences Research Council (EPSRC

Performance evaluation of wake-up radio based wireless body area network

Abstract. The last decade has been really ambitious in new research and development techniques to reduce energy consumption especially in wireless sensor networks (WSNs). Sensor nodes are usually battery-powered and thus have very limited lifetime. Energy efficiency has been the most important aspect to discuss when talking about wireless body area network (WBAN) in particular, since it is the bottleneck of these networks. Medium access control (MAC) protocols hold the vital position to determine the energy efficiency of a WBAN, which is a key design issue for battery operated sensor nodes. The wake-up radio (WUR) based MAC and physical layer (PHY) have been evaluated in this research work in order to contribute to the energy efficient solutions development. WUR is an on-demand approach in which the node is woken up by the wake-up signal (WUS). A WUS switches a node from sleep mode to wake up mode to start signal transmission and reception. The WUS is transmitted or received by a secondary radio transceiver, which operates on very low power. The energy benefit of using WUR is compared with conventional duty-cycling approach. As the protocol defines the nodes in WUR based network do not waste energy on idle listening and are only awakened when there is a request for communication, therefore, energy consumption is extremely low. The performance of WUR based MAC protocol has been evaluated for both physical layer (PHY) and MAC for transmission of WUS and data. The probabilities of miss detection, false alarm and detection error rates are calculated for PHY and the probabilities of collision and successful data transmission for channel access method Aloha is evaluated. The results are obtained to compute and compare the total energy consumption of WUR based network with duty cycling. The results prove that the WUR based networks have significant potential to improve energy efficiency, in comparison to conventional duty cycling approach especially, in the case of low data-reporting rate applications. The duty cycle approach is better than WUR approach when sufficiently low duty cycle is combined with highly frequent communication between the network nodes

Underlying Fermi surface of Sr14−x_{14-x}Cax_xCu24_{24}O41_{41} in two-dimensional momentum space observed by angle-resolved photoemission spectroscopy

We have performed an angle-resolved photoemission study of the two-leg ladder system Sr$_{14-x}$Ca$_x$Cu$_{24}$O$_{41}$ with $x$= 0 and 11. "Underlying Fermi surfaces" determined from low energy spectral weight mapping indicates the quasi-one dimensional nature of the electronic structure. Energy gap caused by the charge density wave has been observed for $x$=0 and the gap tends to close with Ca substitution. The absence of a quasi-particle peak even in $x$=11 is in contrast to the two-dimensional high-$T_c$ cuprates, implying strong carrier localization related to the hole crystalization.Comment: 5 pages, 3 figure

A new approach in chaos shift keying for secure communication

A chaotic sequence for chaos shift keying (CSK) that provides auto- and cross-correlation properties (that are similar to those of random white noise) is used for spread spectrum systems. Due to its bifurcation behavior (depending on the initial condition), the number of chaotic sequences that can be generated by a single formula is not restricted and will not repeat itself. These characteristics provide an increase in system capacity and security performance. The paper presents a study of two different commonly used chaotic logistic maps and a modified chaotic logistic map for CSK spread spectrum system. The newly modified logistic map provides similar bits error rate (BER) performance to the best logistic map. Yet, it also provides an additional chaotic parameter for the control of its dynamic property, hence increasing the system security and capacity

FFT-OFDM for compressed image transmission: performance using structural similarity

While root-mean squared error (RMSE) is a good indicator of error in a received image, it does not always take into account the structure of the image and the way images are perceived by the human eye. Using the newly-proposed structural similarity image measure (SSIM), wavelets previously studied by the authors were analysed again. Results showed a close relationship between RMSE and SSIM, and using a combination of both techniques the Daubechies wavelet family gave slightly better quality images than Biorthogonal family. The auto-correlation of the received images was also used to quantify structural loss