A noise cross PSD estimator for dual-microphone speech enhancement based on minimum statistics

Some two-microphone noise reduction techniques that work in the frequency domain exploit coherence function between two noisy signals. They have shown good results when noise signals on two sensors are uncorrelated, but their performance decreases with correlated noises. Coherence based methods can be improved when the cross power spectral density （CPSD） of correlated noise signals is available. In this paper, we propose a new method for estimation of the CPSD of the noise, which is based on the minimum tracking technique. Despite the fact that the proposed estimator does not need to implement a voice activity detector （VAD）, its performance is comparable to a CPSD estimator that uses an ideal VAD.     

Performance improvement of complementary feeders using static transfer switch system

The performance of complementary feeders, running in parallel, can be significantly improved by installing static transfer switches （STSs） at critical locations. We develop the STS control logic, which transfers the critical load from the preferred feeder to the alternate feeder when a voltage sag or a fault occurs on the preferred feeder. A forced commutation technique is proposed and implemented to turn off the preferred feeders＇ thyristor, thus avoiding cross current to flow and minimizing the transfer time. Simulation results show that the forced commutation technique is more effective as compared to the recently proposed time delay technique for STS operation. Two different feeders, namely New Exchange, the preferred feeder, and Sector 1-10/2, the alternate feeder of Islamabad Electric Supply COmpany （IESCO）, Pakistan, have been selected for case studies. The software PSCAD/EMTDC professional package has been used for simulation.     

Evaluation of Oxidative Stress and DNA Damage in Benign Prostatic Hyperplasia Patients and Comparison with Controls

In the present study, oxidative stress and lymphocytic DNA damage in both pre-op and post-op benign prostrate hyperplasia (BPH) patients with age >50 years was evaluated and compared with normal healthy subjects (controls- without any evidence of disease) of the same sex and age group. From December 2007 to November 2009, oxidative stress in 45 BPH patients were evaluated both before (pre-op patients) and after 7 days of surgery (post-op patients) in terms of measurements of plasma levels of (1) various anti-oxidative enzymes, (2) non-enzymatic antioxidants and (3) malondialdehyde which is a product of lipid peroxidation. The lymphocyte DNA damage was also evaluated by single cell alkaline gel electrophoresis in terms of tail length migration in these patients. These values were compared with their respective control subjects of similar sex and age group. The activities of antioxidant enzymes and the levels of antioxidant, reduced glutathione were found significantly decreased (p < 0.05) in serum samples of pre-operative group of BPH patients as compared to the controls. These altered parameters increased significantly (p < 0.05) and returned to their near normal control values, but not up to baseline values, in post operative patients i.e. after the cancer load was decreased by surgery. Lymphocytic DNA damage was found to be significantly increased in pre-op group as compared to controls and was reduced after surgery in post-op group. The present study therefore, shows significantly increased levels of oxidative stress and DNA damage in BPH patients which were reduced after removal of tumour load. Thus oxidative damage plays an important role in prostate tumourogenesis and timely management of oxidative stress can be of importance in preventing the occurrence of BPH.     

International students’ choice to study in China: an exploratory study

Tertiary Education and Management - International higher education is a major source of revenue in many developed countries. Historically the top destination countries for international students...     

Common European framework of reference for languages (CEFR): insights into global policy borrowing in Malaysian higher education

The Common European Framework of Reference for Languages (CEFR) has emerged as a global policy in language education which has been ‘borrowed’ by nations across the world. This paper presents a critical analysis of Malaysia’s borrowing of the CEFR as part of English language curriculum reform with particular reference to policy motivation and implementation processes as outlined in the English Language Education Roadmap for Malaysia (2015–2025). The analysis draws on Phillips and Ochs’s (2003, “Processes of Policy Borrowing in Education: Some Explanatory and Analytical Devices.” Comparative Education 39 (4): 451–461.) framework for examining educational policy borrowing to highlight challenges as well as prospects of the implementation of the global policy in higher education in Malaysia.     

Perceptions of inequalities in access and usage of ICT in Islamic faith schools

Although the educational experiences of South Asian Muslim women have been studied, little is known regarding the role of technology and its effects on education in this population. This study explores the use of information and communication technologies (ICT) in British Muslim girls’ schools and its effect on learning. It uses primary data from semi-structured interviews with 14–19-year-olds in three Islamic faith schools. Template analysis was used to identify emerging themes. Participants had access to a wide range of technologies and applications; however, access was often limited to classroom settings. Participants also used subject-specific resources available from learning platforms, although this was not consistent across schools and subjects. The participants felt that the range of resources was limited because of their gender and religion, and wanted greater access to ICT, and more online collaboration and social communication. A didactic approach to instruction was prevalent and for many, exacerbated a ‘digital disconnect’. Our findings suggest that Islamic faith schools reinforce lack of home ICT use. The current didactic approach highlights differences with the student-centred pedagogical techniques of early Qur’anic schools. This study encourages a discussion of the challenges of open access to information, religious freedoms and ensuring equality of learning.     

Construction of some hypergroups from combinatorial structures

Jajcay's studies(1993; 1994) on the automorphism groups of Cayley maps yielded a new product of groups, which he called, rotary product. Using this product, we define a hyperoperation ⊙ on the groupSym _e(G), the stabilizer of the identitye∈G in the groupSym(G). We prove that (Sym _e (G), ⊙) is a hypergroup and characterize the subhypergroups of this hypergroup. Finally, we show that the set of all subhypergroups ofSym _e (G) constitute a lattice under ordinary join and meet and that the minimal elements of order two of this lattice is a subgroup ofAut (G).