Manipulation of qubits in non-orthogonal collective storage modes

We present an analysis of transfer of quantum information between the collective spin degrees of freedom of a large ensemble of two-level systems and a single central qubit. The coupling between the central qubit and the individual ensemble members may be varied and thus provides access to more than a single storage mode. Means to store and manipulate several independent qubits are derived for the case where the variation in coupling strengths does not allow addressing of orthogonal modes of the ensemble. While our procedures and analysis may apply to a number of different physical systems, for concreteness, we study the transfer of quantum states between a single electron spin and an ensemble of nuclear spins in a quantum dot

Introduction

The report provides a state-of-the-art of methodologies and guidelines related to quality assurance in water resources modelling. The conclusions from the present report will form the basis for the further HarmoniQuA work on establishment of a common glossary and a generic set of guidelines and methodologies. HarmoniQuA aims to be a component of a future infrastructure for model based water management at catchment and river basin scal

Energy Utilization in Crop and Dairy Production in Organic and Conventional Livestock Production Systems

Searching for livestock production systems with a high energy utilization is of interest because of resource use and pollution aspects and because energy use is an indicator of the intensification of production processes. Due to interactions between crop and livestock enterprises and between levels of different input factors and their effects on yields, it is proposed to analyze agricultural energy utilization through system modelling of data from farm studies. Energy use in small grains, grass-clover and fodder beets registered in organic and conventional mixed dairy farms was analyzed and used together with crop yields in order to model energy prices on three Danish soil types. Conventional crop yields were higher but they also used more indirect energy with input factors, especially fertilizers. The conventional yields were not sufficiently higher to compensate for the extra use of energy compared with the organic crops. The organic crops had lower energy prices on all soil types, with the smallest difference on irrigated sandy soils. Sensitivity analyses were made for the effects of changes in irrigation and fertilizer levels. One conclusion was that better energy utilization in grain crops might be found at intermediate levels of fertilizer use, especially on irrigated soils. Actual farm diesel use was on average 47% higher than expected from standard values, suggesting that care should be taken when basing energetic analysis of farming methods on experimental data alone. On the same farms, the energy use in dairy production registered in organic and conventional mixed dairy farms was analyzed and used together with milk and meat yields in order to model energy prices for three different feeding strategies and two soil types. Conventional dairy production is more intensive with a greater feeding ration and a higher proportion of high-protein Seed, but has also higher yields. The conventional yields were not sufficiently higher to compensate for rite extra use of energy compared with the organic feeding ration. However, the loll er energy price in organic dairy production is dependent on the composition of the feeding strategy. Substitution of 500 SFU of grain with grass pellets makes an ordinary organic feeding ration based on conventional crop production competable. In general, the crop energy price models car? be used together with the dairy production to model the effects of different feeding and crop rotation strategies on the overall energy utilization in mixed dairy production systems

Three-body effects in the Hoyle-state decay

We use a sequential $R$-matrix model to describe the breakup of the Hoyle state into three $\alpha$ particles via the ground state of $^8\mathrm{Be}$. It is shown that even in a sequential picture, features resembling a direct breakup branch appear in the phase-space distribution of the $\alpha$ particles. We construct a toy model to describe the Coulomb interaction in the three-body final state and its effects on the decay spectrum are investigated. The framework is also used to predict the phase-space distribution of the $\alpha$ particles emitted in a direct breakup of the Hoyle state and the possibility of interference between a direct and sequential branch is discussed. Our numerical results are compared to the current upper limit on the direct decay branch determined in recent experiments

Harmonised Principles for Public Participation in Quality Assurance of Integrated Water Resources Modelling

The main purpose of public participation in integrated water resources modelling is to improve decision-making by ensuring that decisions are soundly based on shared knowledge, experience and scientific evidence. The present paper describes stakeholder involvement in the modelling process. The point of departure is the guidelines for quality assurance for `scientific` water resources modelling developed under the EU research project HarmoniQuA, which has developed a computer based Modelling Support Tool (MoST) to provide a user-friendly guidance and a quality assurance framework that aim for enhancing the credibility of river basin modelling. MoST prescribes interaction, which is a form of participation above consultation but below engagement of stakeholders and the public in the early phases of the modelling cycle and under review tasks throughout the process. MoST is a flexible tool which supports different types of users and facilitates interaction between modeller, manager and stakeholders. The perspective of using MoST for engagement of stakeholders e.g. higher level participation throughout the modelling process as part of integrated water resource management is evaluate

A SYSTEM DYNAMICS MODEL OF AGRICULTURE AND RURAL DEVELOPMENT: THE TOPMARD CORE MODEL

The goal of the TOPMARD project is to develop a model of agriculture and rural development to better understand the agronomic, ecological, economic and social dimensions of rural regions. The resulting model, (Policy Model of Multifunctional Agriculture and Rural Development) was built collaboratively and hierarchically by the research teams from the 11 countries. The model features eight subsectors (Land, Agriculture, Tourism, Region, Human Resources, Non-commodities, Capital, and Quality of Life). Imbedded in the model are a complete dynamic input-output model, and an agecohort education demographic model. The model has both supply-side and demand-side drivers. Land use is the key supply-side driver. Land use, coupled with production system choices, determine agricultural and non-commodity outputs. The Quality of Life sector incorporates the coefficients from a regression analysis of migration behaviour to develop a supply-side population response to local quality of life which is added to the demand-side response to job growth.Multifunctionality, system dynamics, policy, model, rural development, Community/Rural/Urban Development, Research Methods/ Statistical Methods, Research and Development/Tech Change/Emerging Technologies,

Institutions and Sustainable Development: The case of Water, Waste and Food

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Energiforbrug i forskellige dyrkningssystemer

Energiforbruget i jordbrugsproduktionen er interessant både fra et ressource synspunkt og fordi udledningen af CO2 fra forbrænding af fossil energi bidrager til drivhuseffekten. Både i målsætningerne for den danske Landsforening for økologisk jordbrug (LØJ) og i landboorganisationernes oplæg til Godt landmandsskab år 2000 indgår desuden mål om at reducere forbruget af fossil energi og få den bedst mulige energiudnyttelse. Ved en kombination af studier i økologiske og konventionelle kvægbrug og brug af standardværdier for dieselforbrug til de enkelte markoperationer er der opstillet modeller for energiforbruget i mark og stald. I energiregnskaberne indgår både det direkte (diesel + el) og det indirekte energiforbrug (f.eks. energi medgået til produktion af den anvendte gødning). Modellerne viste at dieselforbruget per ha er næsten ens i økologisk og konventionel produktion. Det ekstra dieselforbrug til ukrudtsharvning i de økologiske afgrøder opvejes stort set af dieselforbrug til udkørsel af handelsgødning og pesticider i de konventionelle afgrøder. I konventionel produktion udgjorde gødningsforbruget en stor del af energiforbruget, hvorfor energiforbruget per kg korn var henholdsvis 6, 15 og 18% lavere i økologisk produktion på vandet sandjord, lerjord og uvandet sandjord. Energiforbruget per FE græs var tilsvarende 41, 66 og 68 % lavere i økologisk produktion på de tre jordtyper. Udbytterne i økologisk produktion var 15-30% lavere, hvorfor denne produktionsform beslaglægger et større areal til produktion af en given mængde korn og mælk. Dette forhold bør tages i betragtning ved vurdering af energieffektiviteten i de to produktionssystemer, f.eks. ved at modregne den potentielle nettoenergiproduktion på det overskydende areal i konventionel produktion. Jordbrugets samlede udledning af drivhusgasser ville formentlig kunne reduceres med op til 13% regnet i CO2 ækvivalenter ved omlægning til økologisk produktion med fastholdelse af den nuværende animalske produktion