Aspects of moduli stabilization in type IIB string theory

We review moduli stabilization in type IIB string theory compactification with fluxes. We focus on the KKLT and Large Volume Scenario (LVS). We show that the predicted soft SUSY breaking terms in KKLT model are not phenomenological viable. In LVS, the following result for scalar mass, gaugino mass, and trilinear term is obtained: $m_0 =m_{1/2}= - A_0=m_{3/2}$, which may account for Higgs mass limit if $m_{3/2} \sim {\cal O}(1.5)$ TeV. However, in this case the relic abundance of the lightest neutralino can not be consistent with the measured limits. We also study the cosmological consequences of moduli stabilization in both models. In particular, the associated inflation models such as racetrack inflation and K\"ahler inflation are analyzed. Finally the problem of moduli destabilization and the effect of string moduli backreaction on the inflation models are discussed.Comment: 34 pages, 8 figure

Crypto Embedded System for Electronic Document

In this paper, a development of low-cost RSA-based Crypto Embedded System targeted for electronic document security is presented. The RSA algorithm is implemented in a re-configurable hardware, in this case Field Programmable Gate Array (FPGA). The 32-bit soft cores of AlteraÂ’s Nios RISC processor is used as the basic building blocks of the proposed complete embedded solutions. AlteraÂ’s SOPC Builder is used to facilitate the development of crypto embedded system, particularly in hardware/software integration stage. The use of Cryptographic Application Programming Interface (CAPI) to bridge the application and the hardware, and the associated communication layer in the embedded system is also discussed. The result obtained shows that the crypto embedded system provides a suitable compromise between the constraints of speed, space and required security level based on the specific demands of targeted applications

Study on Wonn Defect in 6061 Aluminum Alloy Friction Stir Welded Plates

Friction stir welding (FSW) is a solid-state joining process where the original characteristics of metal remain unchanged. The technique results in high joint strength compared with other welding techniques. It has been widely used fur joining aluminum alloys in the fields of aerospace, marine, automotive, rail and many other applications of commercial importance [1]. Some important process parameters that should be taken into account and control the quality of the weld are the tool spindle speed (rpm), transverse speed (nun/min), plunging speed (nun/min), dwell time (s) and depth of penetration (mm). Studies have shown that during FSW, wormhole (tunnel) defect form along the welded area and the evolved microstructure strongly affects the mechanical properties of the joint. In this investigation, an attempt has been made to understand the influence of welding parameters on worm defect in 6061 aluminum alloy plates. For this project, nine (9) different set of welding parameter combination were used to fubricate the FSW joints. The scope of study is to butt joined two (2) pieces of 6061 aluminum alloy plates having the dimension of lOOmm x lOOmm x lOmm and by rigidly clamped both pieces to perform the welding operation. The project will fucus on tapered pin tool design using AISI H13 Tool Steel Grade. The welding tool will be fubricated using BridgePort PowerPath 15 (CNC Lathe Machine) and undergo heat treatment to increase the hardness level. Meanwhile, the welding process will be conducted using BridgePort VMC 2216 (CNC Milling Machine). By using Optical Microscope (OM), the size worm defect is measured. Microhardness measurements were taken on cross sections of the specimen and were correlated with the size of wormhole defect. The result concludes that increase in ratio of tool transverse feed rate (S) to tool spindle speed (N) will result in increase in the wormhole size (mm2) and decrease in Vickers Microhardness (HV) value

Assessment of water quality impacts for different management practices using SWAT model

The high yield input strategy has been successful in narrowing the gap between food and fiber requirements and the growing population. However, at the same time it has also threatened the sustainability of land and water resources. Best management practices (BMPs) are technically feasible methods for preventing or reducing nonpoint source pollution to a level compatible with water quality goals. Long-term monitoring of BMP impacts is essential to assess their effectiveness under different conditions. However, it is impractical to monitor all BMPs under all conditions due to time and cost constraints. Computer simulation models provide an alternative to evaluate the response of soil and crops to a range of management practices in an efficient and cost effective way. Testing and evaluation of computer models require the use of extensive field data to ensure that they are reliable for the prediction of management effects. This study was designed to: (1) Calibrate and evaluate the subsurface drainage component of SWAT model; (2) Test the ability of SWAT (version 99.2) model for predicting nitrate-nitrogen (N03N) losses with tile flow, by comparing the model output versus measured data; (3) Application of SWAT model on watershed scale.;In general, SWAT adequately tracked the measured tile drain flows, except that the cumulative monthly tile flows were consistently under-predicted. Differences of -8.4 to 6 and 2 to 11% were determined for the annual simulated tile flows as compared to the corresponding measured flows for the calibration and validation period respectively. Calibration of SWAT was performed using tile flow NO3-N loss data measured in 1995 while validation was conducted by comparing the model output with measured NO3-N losses with tile flow observed in 1993--94 and 1996--97. Differences ranging from 2 to 10% and -7.34 to 5.50 were found between annual NO 3-N losses during the calibration period and validation period respectively, indicating that the model tracked the monthly observations reasonably well. However, the peak NO3-N losses were consistently under-predicted for all three combinations of tillage and cropping systems.;The SWAT model was used to estimate the flow and nitrate loading for UMRW watershed. The model was calibrated for stream flow and NO3-N data measured in 1999 at the outlet of the watershed and model was validated for 2000 and 2001 period. The model accurately tracked most of the peak flow events that occurred during the year, although the peaks were usually over predicted. The model tracked the flow reasonably well but model was unable to track the nitrate trend. The underprediction between the simulated and measured annual flow for year 1999 was 24%, while 35% for year 2000 and 12% for year 2001. The NO3-N was over predicted by 25%, 22% and 108% for 1999, 2000, and 2001, indicating the poor performance of SWAT model in NO3-N simulation

Exports-led growth hypothesis in Pakistan: further evidence

The study considers the exports-led growth hypothesis using quarterly data over the period 1990-2008 in case of Pakistan. For this purpose, Ng-Perron unit root test, ARDL bounds testing approach to cointegration and error correction method (ECM) for short run dynamics have been applied. Our results indicate that exports are positively correlated with economic growth confirming the validity of exports-led growth hypothesis. Exchange rate depreciation decreases and real capital stock improves economic growth.Exports, Economic Growth, ARDL Approach

Adoption of internet banking theory of the diffusion of innovation

The innovation diffusion theory (IDT) could be considered as one of the earliest theories that attempts to explore factors that influence an individual to adopt an innovation or a new technology. The theory suggests five key beliefs that influence the adoption of any innovation: relative advantage, complexity, compatibility, trialability, and observability. The purpose of this study was to test part of IDT’s attributes empirically. We used Internet banking as the innovation or the targeted technology. We surveyed 1164 business and MBA students in four public universities in Malaysia. Structural equation modelling was used to analyse the data. The results showed that relative advantage, compatibility, and trialability have a significant effect on att itude. Consequently, attitude significantly aff ects the intention to use Internet banking. Based on the findings, implications to practice are offere

Tissue- and Species-Specific Patterns of RNA metabolism in Post-Mortem Mammalian Retina and Retinal Pigment Epithelium.

Accurate analysis of gene expression in human tissues using RNA sequencing is dependent on the quality of source material. One major source of variation in mRNA quality is post-mortem time. While it is known that individual transcripts show differential post-mortem stability, few studies have directly and comprehensively analyzed mRNA stability following death, and in particular the extent to which tissue- and species-specific factors influence post-mortem mRNA stability are poorly understood. This knowledge is particularly important for ocular tissues studies, where tissues obtained post-mortem are frequently used for research or therapeutic applications. To directly investigate this question, we profiled mRNA levels in both neuroretina and retinal pigment epithelium (RPE) from mouse and baboon over a series of post-mortem intervals. We found substantial changes in gene expression as early as 15 minutes in the mouse and as early as three hours in the baboon eye tissues. Importantly, our findings demonstrate both tissue- and species- specific patterns of RNA metabolism, by identifying a set of genes that are either rapidly degraded or very stable in both species and/or tissues. Taken together, the data from this study lay the foundation for understanding RNA regulation post-mortem and provide novel insights into RNA metabolism in the tissues of the mammalian eye

Sociocultural dynamics affecting the additional language learning process of Arabic-speaking adult refugees in Australian learning settings

This qualitative research study has examined the English Language Learning (ELL) experiences of Arabic-speaking adult refugees to identify the nature of sociocultural dynamics that influence their additional language learning (ALL) in the Australian context. It highlights the positive and negative aspects experienced by former adult refugees when learning the target language (TL) in their attempts to settle in the host country. ALL research (traditionally known as second language acquisition or SLA) acknowledges the role of social factors in learning the TL but it has not yet constructed a framework that groups these social and cultural factors together and explains the relationship between these factors and the ALL process. This study is important because it focuses on the role of sociocultural dynamics in ALL as it is perceived by adult refugee additional language (AL) learners who are already at disadvantage because of the forced and unstable nature of their migration (Reid & Al Khalil, 2013). Hence, the study produces new ways of looking at the sociocultural forces and conditions affecting ALL to inform those involved in the ALL process and assist rethinking the nature of ALL and ways in which to enhance the learning process. Language is not only a means of communication, as it was approached by traditional theories (Ellis, 1994), but also a shared social practice that people use on a daily basis in order to exchange meaning, solve problems and meet their changing social needs. One of the main methodological gaps in ALL research is the absence of the personal views of AL learners on their own language learning experiences. Personal perspectives are valuable tools, which can provide important and rich insights about the nature of ALL (Miller, 1999, 2000). Therefore, this study employed a qualitative narrative inquiry through the use of written biographies and semi-structured interviews in eliciting participants’ perceptions of their ALL experiences (Hopkins, 2009). These narratives of refugee settlement, ELL and social integration reproduce former refugees as human agents with multiple identities (Reid & Al Khalil, 2013). By using content analysis and Discourse analysis, three broad clusters of sociocultural dynamics were conceptualised. These findings suggest that social interaction opportunities, cultural capital and identities influence ALL, based on the understanding that language learning is culturally embedded and a socially mediated process (Lantolf, 2000, pp. 79-80). The findings also indicate that the nature and impact of sociocultural dynamics differ between different AL learners because learners have different learning experiences shaped by different social, cultural and historical contexts. Therefore, understanding the mechanisms of social interaction, learner identities and cultural capital is central to ALL