Analysis of the Single-Crystalline Silicon Photovoltaic (PV) Module Performances Under Low γ - Radiation from Radioactive Source

The present paper is about an experimental evaluation of the terrestrial silicon single-crystalline solar PV module behavior under low gamma radiation. The     

Semi-Empirical Technique for Computation of Glass Density

We present a semi-empirical technique for computation of glass density based on the enthalpy landscape approach. The technique incorporates thermal history and entropy effects into a scaling factor, which is determined using a computed enthalpy versus volume curve and a single experimental density value. We demonstrate the technique on a series of calcium aluminosilicate glasses.     

Urban Livelihoods and Social Networks: Emerging Relations in Informal Recycling in Kaduna, Nigeria

This paper examines the dynamics of the relationships found within existing networks in informal recycling in Kaduna, Nigeria. Special attention is paid to power relations. Informal recycling is a major livelihood activity in cities in the south. Beyond the poverty perspective, the nature of informal recycling makes it an appropriate tool to use to capture the complexity and dynamism of social relations and power within networks. It consists of a variety of interrelated activities performed by different groups. The deep interconnections and interdependences necessitate the formation of networks. Drawing on empirical data, the paper reports that the networks found in Kaduna span the household, community, city, and intercity levels. The relations are informal but, in many cases, well structured. Crucially, the paper reveals that the networks are characterized by dependent relations. Those with greater access to financial and social capitals drive the system and play a greater role in shaping network rules and relations. However, no single actor or group has a monopoly on power. The interdependences mean that the different groups rely on each other, and power becomes much more diffused. Furthermore, network relations are embedded in specific sociocultural contexts. Age and gender are identified as crucial determinants in the dynamics of power and bargaining. The paper argues for a recognition of the diversity and inherent complexity of social networks and the adoption of an analytical approach that is more sensitive to the positionality and power of actors than that found in traditional ??social capitalist?? analysis.     

Design tables for partial-response data transmission filters

Practical design tables are presented for partial-response class 1 data transmission filters. These tables give the pole and zero locations and the main sample point of several filters. This information can be used to analyse the performance of the filters, both in the time domain and frequency domain, thus assisting the user in the choice of a filter to meet the requirements. The filters given in the tables can be syntheised in either active or passive form.     

Artificial intelligence tools and inverse methods for estimating the thermal diffusivity of building materials

The actual European energy context highlights the building sector as one of the largest sectors of energy consumption. Consequently, the “Energy Performance of Buildings Directive”, adopted in 2002 and focusing on energy use in buildings, requires all the EU members to enhance their building regulations and to introduce energy certification schemes, with the aim of both reducing energy consumption and improving energy efficiency. That is why carrying out an energy performance diagnosis is mandatory, notably when buying or selling properties. Indeed, invisible defaults, like, for example, non-emerging cracks or delaminations, could have a detrimental effect on insulating qualities. Esimaing in situ thermo-physical properties allowing locating these defaults, the present work focuses on proposing new and efficient approaches based on the use of both artificial intelligence tools (artificial neural networks and neuro-fuzzy systems) and inverse methods for characterizing building materials i.e. for estimating their thermal diffusivity using thermograms obtained thanks to a non-destructive photothermal method.     

Using modeling,satellite images and existing global datasets for rapid preliminary assessments of renewable energy resources: The case of Mali

This paper presents a novel approach to the preliminary, low-cost, national-scale mapping of wind energy, solar energy and certain categories of bio-energy resources in developing countries, using Mali as an example. The methods applied make extensive use of satellite remote sensing and meteorological mesoscale modeling. The paper presents first results from applying the methodology in Mali and discusses the appropriateness of the results obtained. It is shown that northern Mali has considerable wind energy potential, while average wind speeds in the southern part are too low to make wind power a competitive option. Solar energy resources are shown to be abundant in all of Mali, though the highest values are found in the south. The temporal variation is relatively limited. Bio-energy resources are also concentrated in the south, but there are small pockets of high vegetation productivity in the irrigated areas of the Niger inland delta that might be interesting from a renewable energy resource perspective. Finally, the paper discusses the role that renewable energy resources might play in the energy systems of Mali, given the spatio-temporal distribution of renewable energy resources. It is argued that at the current price of about 70 US$/barrel for fossil fuels, renewable energy resources are becoming economically as well as environmentally attractive options.     

Self-sufficiency policy and irrigated rice productivity in the Senegal River Valley

Senegal’s high dependence on rice imports exposes the country to international market shocks with concomitant serious risks for food security. Since 2011 and triggered by high international prices, several initiatives to upgrade the rice value chain have emerged in the private sector. However, the major constraint private investors are currently facing is the insufficient supply of Senegal River Valley (SRV) paddy rice, implying that investment in productivity is becoming vital for the continuation of their operations, which are currently running below their optimum. The Senegalese government is investing heavily in the national rice sector, with the ambitious objective of achieving self-sufficiency in the year 2015. However, the program focuses primarily on extension of the area grown rather than increased productivity. We provide econometric support for policy making by assessing the determinants of productivity and technical efficiency in irrigated rice production systems through a five-year panel dataset of small-scale irrigated rice farms in the SRV. We found that due to the exacerbation of biological and institutional constraints in the SRV, rice growers had difficulties in maintaining productivity of their land. These constraints prevented them from further intensification, jeopardizing the national objective of self-sufficiency. Farmers exhibited modest technical efficiency levels, suggesting that, in addition to the proposed intensification strategies, substantial efforts in extension services will be required in order to achieve the goal of self-sufficiency. Improved weed and bird control as well as technological, organizational and institutional improvements were identified as key factors for boosting productivity and technical efficiency and, hence, these are target areas needing attention by Senegalese farmers and policy makers in their quest for increased food security.     

Neighborhood Context, Personality, and Stressful Life Events as Predictors of Depression Among African American Women.

The authors tested neighborhood context, negative life events, and negative affectivity as predictors of the onset of major depression among 720 African American women. Neighborhood-level economic disadvantage (e.g., percentage of residents below the poverty line) and social disorder (e.g., delinquency, drug use) predicted the onset of major depression when controlling for individual-level demographic characteristics. Neighborhood-level disadvantage/disorder interacted with negative life events, such that women who experienced recent negative life events and lived in high disadvantage/disorder neighborhoods were more likely to become depressed than were those who lived in more benign settings, both concurrently and over a 2-year period. Neighborhood disadvantage/disorder can be viewed as a vulnerability factor that increases susceptibility to depression following the experience of negative life events. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cost recovery of community-managed piped water systems in Ashanti region, Ghana

Recovering the cost of water services is a major obstacle in achieving a sustainable drinking water supply in developing countries. This paper assesses the levels of cost recovery, household willingness and ability to pay for the full supply cost of water services, and financial management. The study was conducted in five out of 30 community‐managed piped systems in Ashanti region, Ghana. The study shows that the existing tariffs are not sufficient to recover the full supply cost of the service based on the guidelines of the Government Community Water Supply and Sanitation Agency (CWSA). Using 5% of household income as the ability‐to‐pay criteria, 67–87% of the households in the five communities could pay the full supply cost of the service. The poor recovery of the supply cost threatens the long‐term financial sustainability of the small towns' water supply sector.