Battery Modeling

The use of mobile devices is often limited by the capacity of the employed batteries. The battery lifetime determines how long one can use a device. Battery modeling can help to predict, and possibly extend this lifetime. Many different battery models have been developed over the years. However, with these models one can only compute lifetimes for specific discharge profiles, and not for workloads in general. In this paper, we give an overview of the different battery models that are available, and evaluate these models in their suitability to combine them with a workload model to create a more powerful battery model. \u

Computing lifetimes for battery-powered devices

The battery lifetime of mobile devices depends on the usage pattern of the battery, next to the discharge rate and the battery capacity. Therefore, it is important to include the usage pattern in battery lifetime computations. We do this by combining a stochastic workload, modeled as a continuous-time Markov model, with a well-known battery model. For this combined model, we provide new algorithms to efficiently compute the expected lifetime and the distribution and expected value of the delivered charge

On visions and new approaches Case studies of organisational forms in organic plant breeding and seed production

The report is an exploratory study of the social, financial and legal organisation, and technology applied in five initiatives in the sector of biological seed production and plant breeding in the Netherlands, Germany and Switzerland. The experiences of the studied initiatives are relevant in a period in which interest for organic seed and plant breeding is increasing. A number of the actors in the organic sector consider organic breeding a guarantee the availability of suitable seeds and varieties for the organic sector in terms of agronomic and quality traits. An important requirement is that seeds are produced and developed with technologies that are accepted in the organic sector. In addition, the organic sector is interested in breeding strategies that aim not only at economic, but also at social sustainability

Reassembling the political: the PKK and the project of radical democracy

One of the most important secular political movements in the Middle East, the Kurdistan Workers Party (PKK) underwent a profound transformation in the 2000s. What the PKK has experienced in this period was a comprehensive restructuration of its organization, ideology and political-military struggle, changing its course towards a project of radical democracy. In this article we explore the content of this new project, and its practical implications. Through this discussion, our study addresses a gap in Turkish and Kurdish studies. Only few studies deal explicitly with the political ideology of the PKK. The data for this article has been collected through a study of Öcalan’s defence texts and his ‘prison notes’, along with key PKK documents, such as congress reports, formal decisions and the writings of its cadre, such as Mustafa Karasu. We conclude that the project for radical democracy is based on the conception of ‘politics beyond the state, political organisation beyond the party, and political subjectivity beyond class’ and can have the opportunity to change the centralist tradition in Turkish political system as well as the statist and class reductionist political thought in the Left in Turkey

A State of the Art of Self Help Groups in India

This paper considers the strategies of self help group for micro-enterprise development in rural areas. It seeks to answer the question of whether and under which conditions self help groups are an effective vehicle for organizing and representing local people in the development of community based micro-enterprises. Focusing particularly on examples from India in the context of food as a local resource, special attention is paid to success and failure factors of self help groups. While self help group strategies have been applied in the past as a blind replication of success models without considering the intricacies involved in group formation, success of self help groups is based on a thorough understanding of local conditions and possibilities to intervene

Exploring Possibilities to Enhance Food Sovereignty within the Cowpea Production-Consumption Network in Northern Ghana

Over the last years an important focus in the combat of hunger and malnutrition,particularly in Africa has been food security. This article explores possibilities for enhancing food sovereignty, as an alternative concept to food security and an alternative strategy for reversing hunger and malnutrition trends in developing countries. A combination of literature review, participatory appraisal and conventional survey methodologies are used to investigate the relevance of local cowpea (Vigna unguiculata) network regarding its importance vis-à-vis other crops, varietal choice, and consumption patterns in Northern Ghana from food sovereignty perspective. Findings reveal how people in poverty-stricken and hunger- hot- spot communities strive to conserve their biodiversity and production-consumption networks for posterity. Local cowpea varietal preferences are investigated for participatory breeding considerations to improve on seed access for sustainable production. Promotion of origin-based foods in the current fast growing globalised markets is recommended as a possibility to enhance food sovereignty for sustainable development in Afric

Computing Battery Lifetime Distributions

The usage of mobile devices like cell phones, navigation systems, or laptop computers, is limited by the lifetime of the included batteries. This lifetime depends naturally on the rate at which energy is consumed, however, it also depends on the usage pattern of the battery. Continuous drawing of a high current results in an excessive drop of residual capacity. However, during \ud intervals with no or very small currents, batteries do recover to a certain extend. We model this complex behaviour with an inhomogeneous Markov reward model, following the approach of the so-called Kinetic battery Model (KiBaM). \ud The state-dependent reward rates thereby correspond to the power consumption of the attached device and to the available charge, respectively. We develop a tailored numerical algorithm for the computation of the distribution of the consumed energy and show how different workload patterns influence the overall lifetime of a battery