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Janssen S.,University of Bremen | Janssen S.,Microsystems Center Bremen | Janssen S.,Bremen Research Cluster for Dynamics in Logistics LogDynamics | Pankoke I.,Research Institute for Management and Beverage Logistics FIM | And 5 more authors.
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences | Year: 2014

Two important parameters are often neglected in the monitoring of perishable goods during transport: mould contamination of fresh food and the influence of acceleration or vibration on the quality of a product. We assert the claim that it is necessary to focus research on these two topics in the context of intelligent logistics in this opinion paper. Further, the technical possibilities for futuremeasurement systems are discussed. By measuring taste deviations, we verified the effect on the quality of beer at different vibration frequencies. The practical importance is shown by examining transport routes and market shares. The general feasibility of a mobile mould detection system is established by examining the measurement resolution of semiconductor sensors for mould-related gases. Furthermore, as an alternative solution, we present a concept for a miniaturized and automated culture-medium-based system. Although there is a lack of related research to date, new efforts canmake a vital contribution to the reduction of losses in the logistic chains for several products. © 2014 The Author(s) Published by the Royal Society.

Jedermann R.,University of Bremen | Nicometo M.,Iron Mountain | Uysal I.,University of South Florida | Lang W.,University of Bremen | And 2 more authors.
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences | Year: 2014

The need to feed an ever-increasing world population makes it obligatory to reduce the millions of tons of avoidable perishable waste along the food supply chain. A considerable share of these losses is caused by non-optimal cold chain processes and management. This Theme Issue focuses on technologies, models and applications to monitor changes in the product shelf life, defined as the time remaining until the quality of a food product drops below an acceptance limit, and to plan successive chain processes and logistics accordingly to uncover and prevent invisible or latent losses in product quality, especially following the first-expired-firstout strategy for optimized matching between the remaining shelf life and the expected transport duration. This introductory article summarizes the key findings of this Theme Issue, which brings together research study results from around the world to promote intelligent food logistics. The articles include three case studies on the cold chain for berries, bananas and meat and an overview of different post-harvest treatments. Further contributions focus on the required technical solutions, such as the wireless sensor and communication system for remote quality supervision, gas sensors to detect ethylene as an indicator of unwanted ripening and volatile components to indicate mould infections. The final section of this introduction discusses how improvements in food quality can be targeted by strategic changes in the food chain. © 2014 The Author(s) Published by the Royal Society.

Jedermann R.,University of Bremen | Jedermann R.,Microsystems Center Bremen | Praeger U.,Leibniz Institute for Agricultural Engineering | Geyer M.,Leibniz Institute for Agricultural Engineering | And 3 more authors.
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences | Year: 2014

Quality problems occurring during or after sea transportation of bananas in refrigerated containers are mainly caused by insufficient cooling and nonoptimal atmospheric conditions, but also by the heat generated by respiration activity. Tools to measure and evaluate these effects can largely help to reduce losses along the banana supply chain. The presented green life model provides a tool to predict the effect of deviating temperature, relative humidity, and CO2 and O2 gas concentrations on the storage stability of bananas. A second thermal model allows evaluation of the cooling efficiency, the effect of changes in packaging and stowage and the amount of respiration heat from the measured temperature curves. Spontaneous ripening causes higher respiration heat and CO2 production rate. The resulting risk for creation of hot spots increases in positions in which the respiration heat exceeds the available cooling capacity. In case studies on the transport of bananas from Costa Rica to Europe, we validated the models and showed how they can be applied to generate automated warning messages for containers with reduced banana green life or with temperature problems and also for remote monitoring of the ripening process inside the container. © 2014 The Author(s) Published by the Royal Society.

Jedermann R.,University of Bremen | Jedermann R.,Microsystems Center Bremen | Lang W.,University of Bremen | Lang W.,Microsystems Center Bremen | Lang W.,Bremen Research Cluster for Dynamics in Logistics LogDynamics
Refrigeration Science and Technology | Year: 2014

Biological processes continue after harvest in most of the fresh fruits. The generated heat, created by such climacteric fruits, must be removed by a cooling unit, but the amount of heat is also a valuable indicator for the current state of the product. In this paper we will present an approach, how the generated heat can be estimated from the measured temperature over time curve as additional-time varying-process state by the recursive and computational efficient algorithm of the Kalman filter. The application of the Kalman filter required a special adaptation. The parameter for heat removal has to be estimated by system identification techniques in the first step. The resulting time-continuous model has to be translated to a discrete state-space description of the process. Noise covariance matrices had to be defined. The required algorithm was implemented as JAVA code on a processing unit mounted directly in our prototype 'Intelligent Container'. In an application example we showed how the ripening process of bananas can be supervised by the suggested system.

Palafox-Albarran J.,University of Bremen | Palafox-Albarran J.,Bremen Research Cluster for Dynamics in Logistics LogDynamics | Jedermann R.,University of Bremen | Jedermann R.,Microsystems Center Bremen | And 4 more authors.
Information Fusion | Year: 2015

Optimisation of the number of required measurement points and their location is an important research topic in sensor networks. Finding the optimal positions increases spatial coverage and reduces deployment costs. This paper presents an approach for the case that two attributes have to be measured with a different number of available sensors. The proposed cokriging method performs cross-attribute fusion in sensor networks by being based on the analysis of multi-variable spatial correlations. To the best of our knowledge, this scientific work is the first one considering kriging and cokriging interpolations as IF methods. The single-variable ordinary kriging and bi-variable methods were applied to experimental data. The combination of humidity and temperature data in a refrigerated container is used as exemplary case, humidity measurements are considered to be the expensive attribute to measure. The average estimation error for intermediate points was estimated as a function of the number of humidity sensors. When variability is high, data fusion using the bi-variable method produced results as accurate as the single-variable one, without the necessity of deploying a large number of humidity measuring points, by complementing the estimation with temperature measurements. © 2014 Elsevier B.V.

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