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Emerging Development Pathways of Urban Livestock Production in Rapidly Growing West Africa Cities
(2016-11-19)
In this study, we try to capture the degree of specialization or integration, and of intensification or extensification, of (peri-) urban livestock production, along with the factors that influence such decisions and their impact on natural resource uses. A total of 181 and 187 structured questionnaires were completed in livestock-keeping households in Ouagadougou (Burkina Faso) and Tamale (Ghana). Categorical principal component and two-step cluster analysis were used to identify homogenous groups of livestock-keeping ...
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A Hybrid Optimization Method Combining Network Expansion Planning and Switching State Optimization
(2020-07-01)
Combining switching state optimization (SSO) and network expansion planning (NEP) in AC systems results in a mixed-integer non-linear optimization problem. Two methodically different solution approaches are mathematical programming and heuristic methods. In this paper, we develop a hybrid optimization method combining both methods to solve the combined optimization of SSO and NEP. The presented hybrid method applies a DC programming model as an initialization strategy to reduce the search space of the heuristic. A ...
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Stakeholder Influence on Sustainable Supply Chain Management: A Case Study of a German Apparel Frontrunner
(2021-10-12)
Although interest in green and sustainable supply chains has been growing for over a decade in the academic discourse, the textile industry still embraces numerous examples of non-sustainable behavior (i.e., environmental damage, poor working conditions, or modern slavery). While there is a general agreement that stakeholder pressure can lead to more sustainable SCs, a lot remains for a more differentiated stakeholder perspective in sustainable supply chain management (SSCM). Thus, this study aims for theory elaboration ...
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Willingness-to-Pay for District Heating from Renewables of Private Households in Germany
(2020-05-18)
Recent discussion about future energy production promotes the recovery of industrial heat as a potential solution to reduce carbon emissions. Experts call for an expansion of central heating by renewable energy systems to ensure a decarbonization of energy systems. In this context, district heating could play a significant role in city and district planning. Nonetheless, for private households, environmental aspects are only one factor amongst others as, e.g., capital costs, comfort and security. In this study, we ...
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A modification of a traditional Ethiopian maize store for solar powered ambient drying to reduce post-harvest losses
(2020-07-14)
A gombisa is a traditional Ethiopian structure widely used for maize storage over several months. It lacks adequate ventilation for timely moisture removal, which promotes mold development and aflatoxin production. In this study, a traditional gombisa was compared to one modified by installing a solar powered fan to provide forced ambient air ventilation during daytime. Approximately 900 kg of moist ear maize were loaded into each structure and samples from selected locations were weighed periodically to monitor ...
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Comparing different methods for the estimation of interbank intraday yield curves
(2020-01-16)
In this study, we compare three different models, namely, the Nelson–Siegel model (NSM), the Svensson model (SVM), and the Diebold–Li model (DLM), for the estimation of an intraday yield curve on the Italian interbank credit market e‐MID. Using a sample, which spans from October 2005 until March 2010, the first important finding is that all three models are highly suitable for the estimation of an intraday yield curve providing superior empirical results when compared with similar works on e‐MID. The second important ...
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Toward optimal probabilistic active learning using a Bayesian approach
(2021-05-04)
Gathering labeled data to train well-performing machine learning models is one of the critical challenges in many applications. Active learning aims at reducing the labeling costs by an efficient and effective allocation of costly labeling resources. In this article, we propose a decision-theoretic selection strategy that (1) directly optimizes the gain in misclassification error, and (2) uses a Bayesian approach by introducing a conjugate prior distribution to determine the class posterior to deal with uncertainties. ...
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Oxidation Reactions of the N-Heterocyclic Stannylenes [𝘰-C₆H₄ (NSi𝑡BuMe₂)]₂Sn and [{Fe(η⁵ -C₅H₄ -NSi𝑡BuMe₂)₂}Sn] with Sulfur, Selenium, and Diphenyl Diselenide
(2020-01-27)
The N‐heterocyclic stannylenes [{Fe(η$^5$‐C$_5$H$_4$‐NSi𝑡 BuMe$_2$)$_2$}Sn] (1 ) and [𝘰‐C$_6$H$_4$(NSi𝑡 BuMe$_2$)]$_2$Sn (2 ) were prepared in one‐pot reactions from SnCl$_2$, LiN(SiMe$_3$)$_2$, and the corresponding diamine, viz. [Fe(η$^5$‐C$_5$H$_4$‐NHSi𝑡 BuMe$_2$)$_2$] and 𝘰‐C$_6$H$_4$(NSiH𝘵 BuMe$_2$)$_2$, respectively. Oxidative addition reactions of 1 and 2 with S$_8$ and Se$_8$, respectively, afforded the corresponding 1,3,2,4‐dithiadistannetanes ((1 S$_2$), (2 S$_2$)), and 1,3,2,4‐diselenadistannetanes ...
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Urban and Rural Sustainability: Divergent Concepts and Their Consequences for Marketing
(2021-07-02)
Most sustainability innovations are adapted to the needs of urban areas. These innovations are either not offered at all in rural areas (e.g., car sharing) or require massive effort and restrictions to be usable or effective (e.g., ride sharing). Delving deeper than the description scholarly research needs to clarify consumers' conceptualization of sustainability in urban and rural areas. Notably, the extent to which sustainable innovations are adopted and their associated adoption dynamics with the consequences for ...
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Sustainability Transitions in University Food Service—A Living Lab Approach of Locavore Meal Planning and Procurement
(2021-06-29)
Due to its purchasing power, the public food service sector is viewed as a potential transformative driver towards sustainable food systems. Organic meal planning and regional procurement may be a vital implementation strategy towards Planetary Health Diets in the communal catering arena. Capable of unleashing desirable synergies within local foodsheds, this transition pathway can potentially benefit all stages of the value chain, while also positively influencing consumer dietary behavior. Transformation, however, ...