114 research outputs found

    Exploring the impact of urbanization on consumer goods distribution networks

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    Purpose Due to the growing percentage share of urban dwellers, the physical distribution of products faces altering conditions. This research explores the effects that urbanization has on the performance of a fast-moving consumer goods distribution network. A focus is set on changes in distribution cost, the cost-minimal network design, and greenhouse gas emissions. Design/methodology/approach The analyses are based on a quantitative distribution network model of an existing manufacturer of consumer goods. Findings The results indicate that the foreseen population shift will affect the network's economic and environmental performance. Effects are, among others, due to differences in the efficiency of supplying urban and nonurban regions. The combined effects of urbanization and the development of the population size will even more affect the network's performance. Originality/value Research dealing with distribution logistics and urbanization primarily focuses on city logistics. In this paper, the object of analysis is the entire distribution system

    Exploring the impact of traffic congestion on CO2 emissions in freight distribution networks

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    This research quantifies the impact that regular road traffic congestion has on the CO2 emissions of a real-world distribution network, and it studies the consequences when the number of distribution centers changes. For this purpose, this study makes use of a network model allowing for a detailed representation of all relevant transport operations, including production flows between factories and distribution centers, line haul shipments between distribution centers and customers, and round/delivery trips between transshipment points and retailer locations for the last mile. The processed trip and traffic information does not rely on standard traffic data collection approaches, such as interviews, in situ technologies, or floating car data, but the road traffic data are retrieved from an online navigation service, such as Bing Maps, Google Maps, Inrix, Here, and TomTom. This study proves that online navigation services may considerably contribute to future research projects analyzing CO2 sensitivities and greenhouse gas cutting opportunities in logistics networks

    Generating greenhouse gas cutting incentives when allocating carbon dioxide emissions to shipments in road freight transportation

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    Road freight transportation accounts for a great share of the anthropogenic greenhouse gas (GHG) emissions. In order to provide a common methodology for carbon accounting related to transport activities, the European Committee for Standardization has published the European Norm EN-16258. Unfortunately, EN-16258 contains gaps and ambiguities and leaves room for interpretation, which makes the comparison of the environmental performance of different logistics networks still difficult and hinders the identification of best practices. This research contributes to the identification of particularly meaningful principles for the allocation of GHG to shipments in road freight transportation by presenting an analytical framework for studying the performance of the EN-16258 allocation schemes with respect to accuracy, fairness, and the GHG minimizing incentive. In doing so, we continue previous studies that analyzed two important aspects of the EN-16258 allocation rules: accuracy and fairness. This study provides further insights into this allocation problem by investigating the incentive power of the different allocation schemes to opt for the GHG minimal way of running a road freight network. First, we complement the list of transport scenarios introduced in prior studies and present two novel scenarios. Second, we carry out a series of numerical experiments to compare the EN-16258 allocation rules with respect to accuracy, fairness, and the GHG minimizing incentive. We find that the results may differ significantly for the two scenarios, suggesting a case-by-case recommendation. This is particularly interesting because the first scenario confirms the results of the prior studies, while the second scenario rather contradicts them

    Mentale Rotation bei Grundschulkindern: Zusammenhang mit motorischen FĂ€higkeiten und Einfluss motorischer Prozesse

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    In dieser Arbeit wird der Zusammenhang zwischen den motorischen FĂ€higkeiten und der kognitiven FĂ€higkeit der mentalen Rotation, der FĂ€higkeit sich einen Gegenstand beliebig gedreht vorstellen zu können, bei Kindern im Grundschulalter untersucht. ZusĂ€tzlich wird mittels eines Interferenzparadigmas ĂŒberprĂŒft, ob motorische Prozesse, wie sie z. B. zum Drehen eines Knopfes mit der Hand benötigt werden, an der mentalen Rotation beteiligt sind. Außerdem wurde untersucht, ob die motorischen FĂ€higkeiten einen Einfluss auf die Beteiligung solcher motorischer Prozesse an der mentalen Rotation haben. Anhand der Ergebnisse kann festgehalten werden, dass der Zusammenhang zwischen den motorischen FĂ€higkeiten und der mentalen RotationsfĂ€higkeit von mehreren Faktoren moduliert wird. Werden durch das Stimulusmaterial oder durch motorische Aufgaben mit Bezug zur mentalen Rotation die Verwendung motorischer Prozesse bei der mentalen Rotation implizit angeregt, lĂ€sst sich ein signifikanter Zusammenhang zwischen den motorischen FĂ€higkeiten der Kinder und der mentalen RotationsfĂ€higkeit nachweisen. Kinder mit ausgeprĂ€gteren motorischen FĂ€higkeiten machen weniger Fehler im mentalen Rotationstest als Kinder mit weniger ausgeprĂ€gten motorischen FĂ€higkeiten. Außerdem konnte bei 7-8 jĂ€hrigen Jungen eine Interferenz zwischen dem Drehen eines Knopfes in die eine Richtung und der gleichzeitigen mentalen Rotation in die entgegengesetzte Richtung festgestellt werden. Stimmen mentale und manuelle Drehrichtung ĂŒberein, sind die mittleren Reaktionszeiten um 300ms schneller als wenn die Drehrichtungen inkompatibel sind. In einem weiteren Experiment konnte eine Interferenz allein durch einen der mentalen Rotation entgegengesetzten Bewegungsplan nachgewiesen werden. 7-8 JĂ€hrige MĂ€dchen und Jungen hatten um 430ms lĂ€ngere Reaktionszeiten wenn sie wĂ€hrend der mentalen Rotation den Bewegungsplan fĂŒr eine inkompatible Handbewegung aufrechterhalten mussten, als wenn mentale Rotation und Bewegungsplan fĂŒr eine Handbewegung die gleiche Richtung hatten. Ein Zusammenhang zwischen den motorischen FĂ€higkeiten und den Interferenzerscheinungen konnte nicht nachgewiesen werden

    Sustainable City Evaluation Using the Database for Estimation of Road Network Performance

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    This article introduces the Database for Estimation of Road Network Performance (DERNP) to enable wide-scale estimation of relevant Road Network Performance (RNP) factors for major German cities. The methodology behind DERNP is based on a randomized route sampling procedure that utilizes the Worldwide Harmonized Light Vehicles Test Procedure (WLTP) in combination with the tile-based HERE Maps Traffic API v7 and a digital elevation model provided by the European Union’s Earth Observation Programme Copernicus to generate a large set of independent and realistic routes throughout OpenStreetMap road networks. By evaluating these routes using the PHEMLight5 framework, a comprehensive list of RNP parameters is estimated and translated into polynomial regression models for general usage. The applicability of these estimations is demonstrated based on a case study of four major German cities. This case study considers network characteristics in terms of detours, infrastructure, traffic congestion, fuel consumption, and CO2 emissions. Our results show that DERNP and its underlying randomized route sampling methodology overcomes major limitations of previous wide-scale RNP approaches, enabling efficient, easy-to-use, and region-specific RNP comparisons

    Business Analytics and Big Data: Production, Logistics and Supply Chain Management

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    Das Poster befasst sich mit dem Beitrag der Auswertung von "Big Data" fĂŒr die Anwendungsbereiche der Produktion, der Logistik und des Supply Chain Management. Im Kern steht dabei die Anwendung von Business Analytics Methoden und die Umsetzung der Analytics-Ergebnisse in anwendungsorientierte Use Cases. Als Beispiele werden besprochen: Predictive Maintenance, Supply Chain Monitoring, Supply Chain Risk Management, Demand Forecasting

    Dwarfs on the Shoulders of Giants: Bayesian Analysis With Informative Priors in Elite Sports Research and Decision Making

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    While sample sizes in elite sports are necessarily small, so are the effects that may be relevant. This conundrum is complicated by an understandable reluctance of athletes to comply with extensive study requirements. In Bayesian analyses, pre-existing knowledge (e.g., from sub-elite trials) can be formally included to supplement scarce data. Moreover, some design specifics for small sample research extend to the extreme case of a single subject. This provides the basis for actionable feedback (e.g., about individual responses) thereby incentivising participation. As a proof-of-concept, we conducted a replicated cross-over trial on the effect of cold-water immersion (CWI) on sprint performance recovery in soccer players. Times for 30 m linear sprint and the initial 5 m section, respectively, were measured by light gates before and 24 h after induction of fatigue. Data were analysed by Bayesian and by standard frequentist methods. Informative priors are based on a published metaanalysis. Seven players completed the trial. Sprint performance was 4.156 ± 0.193 s for 30 m linear sprint and 0.978 ± 0.064 s for the initial 5 m section. CWI improved recovery of sprint time for the initial 5 m section (difference to control: -0.060 ± 0.060 s, p = 0.004) but not for the full 30 m sprint (0.002 ± 0.115 s, p = 0.959), with general agreement between Bayesian and frequentist interval estimates. On the individual level, relevant differences between analytical approaches were present for most players. Changes in the two performance measures are correlated (p = 0.009) with a fairly good reproducibility of individual response patterns. Bayesian analyses with informative priors may be a practicable and meaningful option particularly for very small samples and when the analytical aim is decision making (use / don't use in the specific setting) rather than generalizable inference

    Speed Limit Induced CO2 Reduction on Motorways: Enhancing Discussion Transparency through Data Enrichment of Road Networks

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    Considering climate change, recent political debates often focus on measures to reduce CO2 emissions. One key component is the reduction of emissions produced by motorized vehicles. Since the amount of emission directly correlates to the velocity of a vehicle via energy consumption factors, a general speed limit is often proposed. This article presents a methodology to combine openly available topology data of road networks from OpenStreetMap (OSM) with pay-per-use API traffic data from TomTom to evaluate such measures transparently by analyzing historical real-world circumstances. From our exemplary case study of the German motorway network, we derive that most parts of the motorway network on average do not reach their maximum allowed speed throughout the day due to traffic, construction sites and general road utilization by network participants. Nonetheless our findings prove that the introduction of a speed limit of 120 km per hour on the German autobahn would restrict 50.74% of network flow kilometers for a CO2 reduction of 7.43% compared to the unrestricted state

    A multi‐criteria decision‐making approach for assembling optimal powertrain technology portfolios in low GHG emission environments

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    Environmental regulations force car manufacturers to renew the powertrain technology portfolio offered to the customer to comply with greenhouse gas (GHG) emission targets. In turn, automotive companies face the task of identifying the “right” powertrain technology portfolio consisting of, for example, internal combustion engines and electric vehicles, because the selection of a particular powertrain technology portfolio affects different company targets simultaneously. What makes this decision even more challenging is that future market shares of the different technologies are uncertain. Our research presents a new decision‐support approach for assembling optimal powertrain technology portfolios while making decision‐makers aware of the trade‐offs between the achievable profit, the achievable market share, the market share risk, and the GHG emissions generated by the selected vehicle fleet. The proposed approach combines “a posteriori” decision‐making with multi‐objective optimization. In an application case, we feed the outlooks of selected market studies into the proposed decision‐support system. The result is a visualization and analysis of the current real‐world decision‐making problem faced by many automotive companies. Our findings indicate that for the proposed GHG restriction at work in 2030 in the European Union, no optimal powertrain technology portfolio with less than 35% of vehicles equipped with an electric motor exists

    A checklist for using Beals’ index with incomplete floristic monitoring data : reply to Christensen et al. (2021): Problems in using Beals’ index to detect species trends in incomplete floristic monitoring data

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    Christensen et al. criticized the application of Beals’ index of sociological favourability to adjust for incomplete species lists when comparing repeated surveys. Their main argument was that using Beals’ conditional occurrence probabilities would systematically underestimate biodiversity change compared to using observed frequencies. Although this might be the case for rare species, as we explicitly stated in our original publication, we here use a worked-out example to show that this criticism is unjustified for species that are sufficiently represented in the reference data set. In our opinion, the misconception derives from ignoring one of the key requirements for applying Beal's index, which is the use of a sufficiently large reference data set to derive a reliable co occurrence matrix. We here show how the predicted probability for the occurrence of a species depends on the size of the reference data set and give recommendations on the premises for applying Beals’ approach for monitoring purposes
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