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At the scale of Switzerland, the national railway company SBB Cargo AG has to schedule its locomotives and drivers in order to be able to pull all trains. Two objective functions are considered in a two-stage lexicographic fashion: (1) the locomotive and driver costs and (2) the driver time that is spent without driving. As the problem instances tend to reach really big sizes (up to 1900 trains), we propose to schedule locomotives and drivers in a sequential way, thus having a sequence of smaller problems to solve. Moreover, for smaller instances, we also propose to schedule jointly locomotives and drivers in an integrated way, therefore increasing the search space but possibly leading to better solutions. In this paper, we present a mathematical formulation and model for the problem. We also consider the contract-related constraints of the drivers, and we propose a way to integrate some time flexibility in the schedules. Next, we propose an innovative matheuristic to solve the problem, relying on a descent local search and a rolling horizon decomposition. An important goal of this method is to explore thoroughly at which extent a general-purpose solver can be used on this problem. Finally, the benefits of each aspect of the model and of the method are analyzed in detail on the results obtained for 20 real SBB Cargo AG instances. [ABSTRACT FROM AUTHOR]

Lack of water use data at the user scale is frequently noted in integrated water management and water demand modelling studies. This situation affects particularly mountain tourist areas, where high seasonal water demand related to the variation of temporary population are rarely documented. Irrigation is also a major water use in moutain territories but is not commonly measured. This paper proposes a framework for local-scale monitoring of seasonal water use behaviours and their territorial inprint. A monitoring strategy was developed to collect water demand data at thin spatio-temporal scales which were analysed using two concepts: (i) the water use regime, describing the dynamics of water uses throughout the year using normalised values, and (ii) the water use density, expressing the territorial footprint of a water use, in terms of unit area. This strategy was applied in the alpine tourist municipality of Montana (Switzerland). A two-year monitoring campaign of irrigation and drinking water uses was carried out combining in-field measurement (water metres) with interviews of water users. The temporal resolution of the collected water use dataset (bi-weekly, daily) was sufficient to assess the specific water demand patterns and the short-term water use peaks responsible for water stress in Alpine tourist regions. It provided the first irrigation monitoring in the area and a classification of drinking water data according to their spatial distribution, the type of building and the permanency of residents. The water use density method gives a new prespective on the spatial intensity of water uses, highlighting the importance of garden irrigation in Montana. Also, the water use regime method identified July as the period of water demand peaking. The monitoring of water uses at such thin temporal scale constitutes the necessary dataset for the creation of water balance models that accurately reproduce the effective water use behaviours. [ABSTRACT FROM AUTHOR]

Trees that characterized many agricultural landscapes across Europe are declining, despite the recent revival of agroforestry research and increasing direct payments for their maintenance. Therefore, in addition to field experiments, there is a need for transdisciplinary research in close alliance with local farmers. This paper proposes a three-step participatory design and assessment approach, incorporating local innovation and scientific evidence. To our knowledge, this is the first participatory and bioeconomic analysis of farmer-designed agroforestry systems in Europe. First, an exploratory survey of farmers' innovations in Switzerland was conducted together with a literature review. Based on the survey, 14 representative agroforestry practices were defined for the bioeconomic assessment, focusing on walnut ( Juglans hybr.) and wild cherry ( Prunus avium) . The predictions of long-term yields were made with the Yield-SAFE model, and the profitability was assessed using the Farm-SAFE model. The survey results suggested a lack of local knowledge on key ecosystem services provided by agroforestry. It is therefore recommended to apply the concept of ecosystem services, in order to support the design of multifunctional agriculture and to increase the willingness to pay for its services. According to our yield predictions, mixing trees and crops was commonly more productive (12 out of the 14 options, land equivalent ratio = 0.95-1.30) than growing them in separate forestry or arable systems. This result contradicts the widespread view among modern Swiss farmers that agroforestry is unproductive. In terms of profitability, 68 % of the 56 financial scenarios for the agroforestry practices, particularly those linked to innovative marketing of fruit or receiving payments for ecosystem services, were found to be more profitable than the business as usual reference systems. These results demonstrate that there is a need and a value in bridging the gap between scientists and farmers, in order to coproduce applied knowledge for the design of productive agroforestry practices. [ABSTRACT FROM AUTHOR]

Heckman’s (Ann Econ Soc Meas 4(5), 475–492, ; Econometrica 47, 153–161, ) sample selection model has been employed in three decades of applications of linear regression studies. This paper builds on this framework to obtain a sample selection correction for the stochastic frontier model. We first show a surprisingly simple way to estimate the familiar normal-half normal stochastic frontier model using maximum simulated likelihood. We then extend the technique to a stochastic frontier model with sample selection. In an application that seems superficially obvious, the method is used to revisit the World Health Organization data (WHO in The World Health Report, WHO, Geneva ; Tandon et al. in Measuring the overall health system performance for 191 countries, World Health Organization, ) where the sample partitioning is based on OECD membership. The original study pooled all 191 countries. The OECD members appear to be discretely different from the rest of the sample. We examine the difference in a sample selection framework. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to determine the intention to use pre-exposure prophylaxis (PrEP) when available and to identify predictors of the intention to use PrEP among men who have sex with men (MSM) living in Switzerland. The theoretical model drew on the Unified Theory of Acceptance and Use of Technology and considered additional variables related specifically to PrEP, HIV protection and the resources of MSM.Subject and methods: For data collection, we used an anonymous, standardized self-administered online questionnaire. In 2015, we gathered a convenience sample of 556 HIV-negative MSM living in Switzerland. We analyzed the data using descriptive and bivariate statistics and used structural equation modeling to test the hypothesized model.Results: Predictors of respondents’ moderate intention to use PrEP were performance expectancy, effort expectancy, perceived social influence, concerns about using PrEP, attitudes toward condom use, negative experiences of condom use and age. These variables were predicted by HIV protection-related aspects and resources.Conclusion: The findings provide insights into the complex dynamic underlying the intention to use PrEP. [ABSTRACT FROM AUTHOR]

We consider the top forward-backward (FB) asymmetry at the Tevatron and top charge asymmetry at the LHC within chiral U(1)′ models with flavor-dependent U(1)′ charges and flavored Higgs fields, which were introduced in Ko et al. (J. High Energy Phys. 1201:147, ). In this model, one has to include the flavor-changing couplings of the Higgs bosons as well as the Z′ to the up-type quarks. The models could enhance not only the top forward-backward asymmetry at the Tevatron, but also the top charge asymmetry at LHC, without too large same-sign top-quark pair production rates. Also the $m_{t\bar{t}}$ distribution at high $m_{t\bar{t}}$ shows less deviations from the SM predictions. We identify parameter spaces for the U(1)′ gauge boson and (pseudo) scalar Higgs bosons where all the experimental data could be accommodated, including the case with about 125 GeV Higgs boson, as suggested recently by ATLAS and CMS. [ABSTRACT FROM AUTHOR]

We describe the implementation details of the colour reconnection model in the event generator Herwig++. We study the impact on final-state observables in detail and confirm the model idea from colour preconfinement on the basis of studies within the cluster hadronization model. Moreover, we show that the description of minimum bias and underlying event data at the LHC is improved with this model and present results of a tune to available data. [ABSTRACT FROM AUTHOR]

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In Summer 2002 eddy covariance flux measurements of CO2 were performed over a dense urban surface. The month-long measurements were carried out in the framework of the Basel Urban Boundary Layer Experiment (BUBBLE). Two Li7500 open path analysers were installed at z/z H = 1.0 and 2.2 above a street canyon with z H the average building height of 14.6 m and z the height above street level. Additionally, profiles of CO2 concentration were sampled at 10 heights from street level up to 2 z H . The minimum and maximum of the average diurnal course of CO2 concentration at 2 z H were 362 and 423 ppmv in late afternoon and early morning, respectively. Daytime CO2 concentrations were not correlated to local sources, e.g. the minimum occurred together with the maximum in traffic load. During night-time CO2 is in general accumulated, except when inversion development is suppressed by frontal passages. CO2 concentrations were always decreasing with height and correspondingly, the fluxes – on average – always directed upward. At z/z H = 2.2 low values of about 3 µmol m−2 s−1 were measured during the second half of the night. During daytime average values reached up to 14 µmol m−2 s−1. The CO2 fluxes are well correlated with the traffic load, with their maxima occurring together in late afternoon. Daytime minimum CO2 concentrations fell below regional background values. Besides vertical mixing and entrainment, it is suggested that this is also due to advection of rural air with reduced CO2 concentration. Comparison with other urban observations shows a large range of differences among urban sites in terms of both CO2 fluxes and concentrations. [ABSTRACT FROM AUTHOR]