Water quality modelling: microbial risks associated with manure on pasture and arable land

While agricultural activities, such as the application of manure on arable land and animal grazing on pastures, provide economic and environmental benefits, they may also pose microbial risks to water sources. The aim of this paper was to study the microbial fate and transport in an agricultural catchment and recipient water source through further development of the hydrological model HYPE. Hydrological modelling was combined with hydrodynamic modelling to simulate the fate and transport of Salmonella spp., verotoxin-producing Escherichia coli O157:H7 and Cryptosporidium parvum in an agricultural catchment of a drinking water source, Lake Vombsj\uf6n, in Sweden. This approach was useful to study the influence of different processes on the pathogen fate and transport, and to interpret the relative changes in the simulated concentrations. Sensitivity analysis indicated that the largest uncertainties in the model were associated with the estimation of pathogen loads, parameterisation of the pathogen processes, and simulation of partitioning between surface runoff and infiltration. The proposed modelling approach is valuable for assessing the relative effect of different risk-reducing interventions

A liveness checking algorithm that counts

We present a simple but novel algorithm for checking liveness properties of finite-state systems, called k-Liveness, which is based on counting and bounding the number of times a fairness constraint can become true. Our implementation of the algorithm is completely SAT-based, works fairly well in practice, and is competitive in performance with alternative methods. In addition, we present a pre-processing technique which can automatically derive extra fairness constraints for any given liveness problem. These constraints can be used to potentially boost the performace of any liveness algorithm. The experimental results show that the extra constraints are particularly beneficial in combination with our k-Liveness algorithm

Forest cover change in Sri Lanka: The role of small scale farmers

Forest cover in Sri Lanka has decreased rapidly during the last century and only fragments of the once widespread natural forest cover remain. This paper analyzes forest cover change and small scale farmers\u27 relation to natural forests around two protected forest areas in Sri Lanka; Kanneliya Forest Reserve and Knuckles Conservation Forest. Methods used are spatial analysis to observe changes in forest cover from the 1980s until 2010, interviews with small scale farmers and key informants as well as field observations. In Kanneliya Forest Reserve, a decrease in forest cover is observed, particularly due to population increase and expanding tea plantations. In Knuckles Conservation Forest on the other hand, we find an overall increase in forest cover due to expansion of tree plantations, a ban on shifting cultivation and emigration from the area followed by natural forest regeneration. Agriculture is the most common source of income in both study areas and there is a clear link between conversions of forests to agricultural expansion. The profits from agricultural activities are in general insufficient to sustain small scale farmers\u27 needs and the most common alternative source of income is achieved through resources extracted from the forest. Since 2001, demarcation of forest boundaries around the two forest reserves has reduced encroachment and illegal felling of timber. However, this policy has simultaneously threatened the livelihoods of peripheral communities in the forest buffer zones, especially in the investigated villages around Knuckles Conservation Forest. Despite successful attempts to reduce deforestation rates through governmental interventions, further incorporation of local people into the management of forests as stipulated in the current forest policy should be continued. (C) 2012 Elsevier Ltd. All rights reserved

Battery Electric Vehicle Performance Evaluation by Considering Punching Effect on PMSM Iron Cores

Increasing demand for electric vehicles has put significant stress on designing highly efficient electric machines. Manufacturing processes of the electrical steel sheets used in the iron cores of machines deteriorate the electromagnetic properties of the material and increase iron losses. The improved quantification of iron losses in the early stages of the machine design is crucial and enables designers to properly account for losses. However, the complexity and variety of contributing factors in determining these losses have led machine designers to use empirical correction factors to predict iron losses reasonably well. In this work, deterioration of electromagnetic properties of electrical steel sheets due to punching has been considered when simulating the torque and loss performance of a permanent magnet synchronous machine. Three levels of degradation are investigated and the results show up to 10 %, 20 %, and 35 % increase in the hysteresis losses of the machine for a low, a medium and a high degradation level, respectively. Furthermore, the machine performance in selected test-driving cycles is determined as well

HALO: Haskell to Logic through Denotational Semantics

Even well-typed programs can go wrong in modern functional languages, by encountering a pattern-match failure, or simply returning the wrong answer. An increasingly-popular response is to allow programmers to write contracts that express semantic properties, such as crash-freedom or some useful post-condition. We study the static verification of such contracts. Our main contribution is a novel translation to first-order logic of both Haskell programs, and contracts written in Haskell, all justified by denotational semantics. This translation enables us to prove that functions satisfy their contracts using an off-the-shelf first-order logic theorem prover

Near-Field Scanning Microwave Microscopy in the Single Photon Regime

\ua9 2019, The Author(s). The microwave properties of nano-scale structures are important in a wide variety of applications in quantum technology. Here we describe a low-power cryogenic near-field scanning microwave microscope (NSMM) which maintains nano-scale dielectric contrast down to the single microwave photon regime, up to 109 times lower power than in typical NSMMs. We discuss the remaining challenges towards developing nano-scale NSMM for quantum coherent interaction with two-level systems as an enabling tool for the development of quantum technologies in the microwave regime