An objective based classification of aggregation techniques for wireless sensor networks

Wireless Sensor Networks have gained immense popularity in recent years due to their ever increasing capabilities and wide range of critical applications. A huge body of research efforts has been dedicated to find ways to utilize limited resources of these sensor nodes in an efficient manner. One of the common ways to minimize energy consumption has been aggregation of input data. We note that every aggregation technique has an improvement objective to achieve with respect to the output it produces. Each technique is designed to achieve some target e.g. reduce data size, minimize transmission energy, enhance accuracy etc. This paper presents a comprehensive survey of aggregation techniques that can be used in distributed manner to improve lifetime and energy conservation of wireless sensor networks. Main contribution of this work is proposal of a novel classification of such techniques based on the type of improvement they offer when applied to WSNs. Due to the existence of a myriad of definitions of aggregation, we first review the meaning of term aggregation that can be applied to WSN. The concept is then associated with the proposed classes. Each class of techniques is divided into a number of subclasses and a brief literature review of related work in WSN for each of these is also presented

Aid Volatility, Policy and Development

We build on Bulir and Hamann's analysis of aid volatility (2003, 2005), showing that the conclusions reached depend on the dataset used. Their argument that the poorest countries have the highest volatility appears not to be correct. The impact of volatility on growth is negative overall, but differs between positive and negative volatility. The mix between `responsive´ components of aid, e.g. programme aid, and `proactive´ components, e.g. technical assistance, is important. Finally, we conclude that measures which increase trust between donor and recipient, and reductions in the degree of donor `oligopoly´, reduce aid volatility without obviously reducing its effectiveness

Trust in Scientists and Food Manufacturers, with Implications for the Public Support of Biotechnology

The purpose of this paper is to determine what factor affect trust in scientists and food manufacturers, and to examine how trust in these institutions affects public support for biotechnology. Data from the U.S. Biotechnology Study reveal that benefits from biotechnology and expectations of trustworthiness are correlated with trust in scientists, but benefits and costs of biotechnology, and expectations of trustworthiness and competence of biotechnology institutions, are important determinants of trust in food manufacturers. The data also reveal that trust in scientists and food manufacturers has a large and important effect on public support for biotechnology, but trust in scientists is more important for public support than trust in food manufacturers.Food Consumption/Nutrition/Food Safety, L65, Q18,

On the impact of trust on consumer willingness to purchase GM food : evidence from a European survey

Many researches try to explain consumer’s acceptance and opposition to GMO with focus on social factors. With a causal or an associationist theoretical model, different authors put forward the notion of trust as determining to define the position of individuals. Because as in the present case we could fear the simultaneity of decisions (trust, risk perceptions and acceptability), we have to take into account this endogeneity risk. With data from a European Survey (Eurobarometer 64.3 2005), multivariate probit was used to specify the importance of trust in the various organizations involved in the public debate on the acceptance of genetically modified foods on behalf of the “ordinary citizens”. We discuss this portrait of European citizens that shows them to be increasingly optimistic about biotechnology, while being divided on this question.BIOTECHNOLOGY;CONSUMER ATTITUDE;TECHNOLOGY;EUROPEAN SURVEY DATA;GENETICALLY MODIFIED FOOD;MULTIVARIATE PROBIT;TRUST

The economics of accreditation

This paper is a report on a research project on the economics of accreditation in the UK. The main motivation and objective for the study is to have available a detailed analysis of how the accreditation system impinges on important aspects of economic life, such as innovation and business and economic performance. It aims to improve the general understanding of the benefits of using accredited conformity assessment and to help businesses make informed decisions when procuring conformity assessment and related services. It is also intended to be helpful to government by supporting evidence-based policy making in relation to accreditation and conformity assessmen

Trust in Scientists and Food Manufacturers: Implications for the Public Support of Biotechnology

An analysis of data from the U.S. Biotechnology Study, 1997S1998 reveals that few variables affect public trust in scientists, while variables representing perceived benefits, risks, trustworthiness, and competence affect trust in food manufacturers on matters of biotechnology. Both trust in scientists and trust in food manufacturers have a large and important effect on public support for biotechnology, although trust in scientists is found to be more important than trust in food manufacturers. Findings of this analysis suggest that trust in scientists is relatively generalized, while trust in food manufacturers is particularized.biotechnology, genetic modification, public support of biotechnology, public trust, trust, Agribusiness, Food Consumption/Nutrition/Food Safety,

Productivity, Factor Accumulation and Social Networks: Theory and Evidence

The paper analyzes how social barriers to communication affect economy-wide productivity and factor accumulation. Using a dynamic model of an economy that includes a reproducible capital stock (physical or human) and effective labor, a negative relationship is shown to exist between social barriers to communication and total factor productivity (TFP), per capita consumption and reproducible capital. Robust estimates obtained from cross-country data are consistent with the model’s predictions. The theory and empirical results help explain cross-country differences in TFP, the high productivity performance of leading industrialized countries and how productivity ‘catch up’ may be initiated.productivity, dynamic model, barriers to communication

Multipair Massive MIMO Relaying Systems with One-Bit ADCs and DACs

This paper considers a multipair amplify-and-forward massive MIMO relaying system with one-bit ADCs and one-bit DACs at the relay. The channel state information is estimated via pilot training, and then utilized by the relay to perform simple maximum-ratio combining/maximum-ratio transmission processing. Leveraging on the Bussgang decomposition, an exact achievable rate is derived for the system with correlated quantization noise. Based on this, a closed-form asymptotic approximation for the achievable rate is presented, thereby enabling efficient evaluation of the impact of key parameters on the system performance. Furthermore, power scaling laws are characterized to study the potential energy efficiency associated with deploying massive one-bit antenna arrays at the relay. In addition, a power allocation strategy is designed to compensate for the rate degradation caused by the coarse quantization. Our results suggest that the quality of the channel estimates depends on the specific orthogonal pilot sequences that are used, contrary to unquantized systems where any set of orthogonal pilot sequences gives the same result. Moreover, the sum rate gap between the double-quantized relay system and an ideal non-quantized system is a moderate factor of $4/\pi^2$ in the low power regime.Comment: 14 pages, 10 figures, submitted to IEEE Trans. Signal Processin

On the impact of trust on consumer willingness to purchase GM food:Evidence from a European survey

Many researchers try to explain consumer’s acceptance and opposition to genetically modified organisms (GMOs) using social factors like “trust” in “direct causal” or “joint causal” (also referred to as “associationist”) models. The latter approach considers attitudes to Genetically Modified foods (GM foods) to be jointly determined by trust and risk perception. With data from a European Survey (Eurobarometer 64.3, 2005), we use a recursive mixed process model to specify the importance of trust in the various organizations involved in the public debate on the acceptance of genetically modified foods on behalf of the “ordinary citizens”. We discuss the resulting portrait of European citizens that shows them to be increasingly optimistic about biotechnology, while being divided on this question. We show that corroboration of direct causal or joint causal models depend on the organizations concerned.biotechnology, consumer attitudes towards technology, Eurobarometer, genetically modified food, recursive mixed-process model, trust

Beyond the Veil of Ignorance: The Influence of Direct Democracy on the Shadow Economy

In this paper we analyze the influence of direct democratic institutions on the size and development of the shadow economies. The framework developed predicts a negative relationship between the degree of direct democracy and the size of the shadow economy. Countries where direct democratic institutions support democratic life are expected to be characterized by a lower informal sector, ceteris paribus. The empirical / econometric investigation of a sample of 56 democracies confirms our core hypothesis and demonstrates that the effect of direct democratic institutions on the shadow economy is negative and quantitatively important; the results are robust and also depend on the interaction of direct democracy with other political institutions, such as district magnitude.shadow economy, direct democratic institutions, district magnitude, good governance