Performance and economic analysis of hybrid microhydro systems

Microhydro (MHP) systems usually employ unregulated turbines and an electronic load controller, a demand-side control device. Existing analytical models for such systems are lacking details, especially supply-side flow control, for performance simulation at hourly or sub-hourly scales. This work developed stochastic models for downscaling of streamflow and an empirical model of MHP systems. We integrated these models within the framework of Hybrid2 tool to simulate the long-term performance of a tri-hybrid system consisting of hydropower, solar PV and wind turbine. Based on an additive model of time series decomposition, we develop a Multiple Input Single Output (MISO) model in order to synthesize an hourly time series of streamflow. The MISO model takes into account daily precipitation dataset as well as regional hydrological characteristics. The model employs a constrained Monte-Carlo Markov Chain (MCMC) algorithm which is validated against an hourly time series of flow data at Blue River at Blue, Oklahoma. A non-dimensional performance model of MHP systems is developed based on empirical data from Nepal. Three design configurations are presented for a case study. The results show that, along with a small pond that can store water for an hour at the rated capacity of MHP system, a hybrid system with half the size of the battery bank can supply the load year around at Thingan Project in Nepal. This system meets the availability requirements of the Multi-Tier Framework for measuring energy access for household supply. The new proposed system is marginal in the economic sense as well. This project can never recover the initial capital cost at a current rate of the tariff which is about 7 cents/kWh. Other O&M risks aside, the sensitivity analysis suggests that the system may barely recover the initial capital cost, excluding the subsidy, at twice the existing rate of tariff and half the interest rate. This study aspires to come up with better techniques to simulate hybrid microhydro systems and enhance their design and operation through more effective utilization of resources

Implicit cognitions in awareness: Three empirical examples and implications for conscious identity.

open accessAcross psychological science the prevailing view of mental events includes unconscious mental representations that result from a separate implicit system outside of awareness. Recently, scientific interest in consciousness of self and the widespread application of mindfulness practice have made necessary innovative methods of assessing awareness during cognitive tasks and validating those assessments wherever they are researched. Studies from three areas of psychology, self-esteem, sustainability thinking, and the learning of control systems questioned the unconscious status of implicit cognitions. The studies replicated published results using methods of investigating (a) unselective learning of a control task (b) implicit attitudes using IAT, and (c) the Name-letter effect. In addition, a common analytic method of awareness assessment and its validation was used. Study 1 demonstrated that learned control of a dynamic system was predicted by the validity of rules of control in awareness. In Study 2, verbal reports of hesitations and trial difficulty predicted IAT scores for 34 participants’ environmental attitudes. In Study 3, the famous Name-letter effect was predicted by the validity of university students’ reported awareness of letter preference reasons. The repeated finding that self knowledge in awareness predicted what should be cognitions outside of awareness, according to the dual processing view, suggests an alternative model of implicit mental events in which associative relations evoke conscious symbolic representations. The analytic method of validating phenomenal reports will be discussed along with its potential contribution to research involving implicit cognitions

Empirical studies of open source evolution

Copyright @ 2008 Springer-VerlagThis chapter presents a sample of empirical studies of Open Source Software (OSS) evolution. According to these studies, the classical results from the studies of proprietary software evoltion, such as Lehman’s laws of software evolution, might need to be revised, if not fully, at least in part, to account for the OSS observations. The book chapter also summarises what appears to be the empirical status of each of Lehman’s laws with respect to OSS and highlights the threads to validity that frequently emerge in these empirical studies. The chapter also discusses related topics for further research

The Impact Of Technology Trust On The Acceptance Of Mobile Banking Technology Within Nigeria

With advancement in the use of information technology seen as a key factor in economic development, developed countries are increasingly reviewing traditional systems, in various sectors such as education, health, transport and finance, and identifying how they may be improved or replaced with automated systems. In this study, the authors examine the role of technology trust in the acceptance of mobile banking in Nigeria as the country attempts to transition into a cashless economy. For Nigeria, like many other countries, its economic growth is linked, at least in part, to its improvement in information technology infrastructure, as well as establishing secure, convenient and reliable payments systems. Utilising the Technology Acceptance Model, this study investigates causal relationships between technology trust and other factors influencing user’s intention to adopt technology; focusing on the impact of seven factors contributing to technology trust. Data from 1725 respondents was analysed using confirmatory factor analysis and the results showed that confidentiality, integrity, authentication, access control, best business practices and non-repudiation significantly influenced technology trust. Technology trust showed a direct significant influence on perceived ease of use and usefulness, a direct influence on intention to use as well as an indirect influence on intention to use through its impact on perceived usefulness and perceived ease of use. Furthermore, perceived ease of use and perceived usefulness showed significant influence on consumer’s intention to adopt the technology. With mobile banking being a key driver of Nigeria’s cashless economy goals, this study provides quantitative knowledge regarding technology trust and adoption behaviour in Nigeria as well as significant insight on areas where policy makers and mobile banking vendors can focus strategies engineered to improve trust in mobile banking and increase user adoption of their technology

Crime and Social media

Purpose-The study complements the scant macroeconomic literature on the development outcomes of social media by examining the relationship between Facebook penetration and violent crime levels in a cross-section of 148 countries for the year 2012. Design/methodology/approach-The empirical evidence is based on Ordinary Least Squares (OLS), Tobit and Quantile regressions. In order to respond to policy concerns on the limited evidence on the consequences of social media in developing countries, the dataset is disaggregated into regions and income levels. The decomposition by income levels included: low income, lower middle income, upper middle income and high income. The corresponding regions include: Europe and Central Asia, East Asia and the Pacific, Middle East and North Africa, Sub-Saharan Africa and Latin America. Findings-From OLS and Tobit regressions, there is a negative relationship between Facebook penetration and crime. However, Quantile regressions reveal that the established negative relationship is noticeable exclusively in the 90th crime decile. Further, when the dataset is decomposed into regions and income levels, the negative relationship is evident in the Middle East and North Africa (MENA) while a positive relationship is confirmed for sub-Saharan Africa. Policy implications are discussed. Originality/value- Studies on the development outcomes of social media are sparse because of a lack of reliable macroeconomic data on social media. This study primarily complemented three existing studies that have leveraged on a newly available dataset on Facebook

Empirical evaluation of an adaptive e-learning system and the effects of knowledge, learning styles and multimedia mode on student achievement

This paper presents an empirical evaluation of an adaptive e-learning system (AES). The system was evaluated in an experimental research. During the 9 weeks of experimentation, the students studied the learning material in two randomly allocated groups, an experimental group using the AES and a control group using the non-AES. Research findings are described as follows. Students who learned using the AES performed better significantly than those who learned using the non-AES. The implementation of test repetition as a function of knowledge adaptation in the AES increased student achievement significantly. When the effect of test repetition was removed, the implementation of learning style and multimedia mode adaptation in the AES was still found to have significant effect upon student performance. Students whose learning style and multimedia preferences were matched with the system achieved better results

A theory-grounded framework of Open Source Software adoption in SMEs

This is a post-peer-review, pre-copyedit version of an article published in European Journal of Information Systems. The definitive publisher-authenticated version Macredie, RD and Mijinyawa, K (2011), "A theory-grounded framework of Open Source Software adoption in SMEs", European Journal of Informations Systems, 20(2), 237-250 is available online at: http://www.palgrave-journals.com/ejis/journal/v20/n2/abs/ejis201060a.html.The increasing popularity and use of Open Source Software (OSS) has led to significant interest from research communities and enterprise practitioners, notably in the small business sector where this type of software offers particular benefits given the financial and human capital constraints faced. However, there has been little focus on developing valid frameworks that enable critical evaluation and common understanding of factors influencing OSS adoption. This paper seeks to address this shortcoming by presenting a theory-grounded framework for exploring these factors and explaining their influence on OSS adoption, with the context of study being small- to medium-sized Information Technology (IT) businesses in the U.K. The framework has implications for this type of business – and, we will suggest, more widely – as a frame of reference for understanding, and as tool for evaluating benefits and challenges in, OSS adoption. It also offers researchers a structured way of investigating adoption issues and a base from which to develop models of OSS adoption. The study reported in this paper used the Decomposed Theory of Planned Behaviour (DTPB) as a basis for the research propositions, with the aim of: (i) developing a framework of empirical factors that influence OSS adoption; and (ii) appraising it through case study evaluation with 10 U.K. Small- to medium-sized enterprises in the IT sector. The demonstration of the capabilities of the framework suggests that it is able to provide a reliable explanation of the complex and subjective factors that influence attitudes, subjective norms and control over the use of OSS. The paper further argues that the DTPB proved useful in this research area and that it can provide a variety of situation-specific insights related to factors that influence the adoption of OSS