57 research outputs found
Editorial: Supply Chain Management
No full textThis special issue has followed up the 3rd Olympus International Conference on Supply Chains held on Athens Metropolitan Expo, November 7 & 8 2015, Greece.
The Conference was organized by the Department of Logistics Technological Educational Institute of Central Macedonia, in collaboration with the: a) Laboratory of Quantitative Analysis, Logistics and Supply Chain Management of the Department of Mechanical Engineering, Aristotle University of Thessaloniki (AUTH), b) Greek Association of Supply Chain Management (EEL of Northern Greece) and the c) Supply Chain & Logistics Journal.
During the 2-Days Conference more than 60 research papers were presented covering the following thematic areas: (i) Transportation, (ii) Best Practices in Logistics, (iii) Information and Communication Technologies in Supply Chain Management, (iv) Food Logistics, (v) New Trends in Business Logistics, and (vi) Green Supply Chain Management. Three keynote invited speakers addressed interesting issues for the Operational Research, the Opportunities and Prospects of Greek Ports chaired Round Tables with other Greek and Foreign Scientists and Specialists
Conceptual design of a telecommunications equipment container for humanitarian logistics
No full textPreparedness addresses the strategy in disaster management that allows the implementation of successful operational response immediately after a disaster. With speed as the main driver, product design for humanitarian aid purposes is a key factor of success in situations of high uncertainty and urgency. Within this context, a telecommunications container (TC) has been designed that belongs to a group of containers that serve the purpose of immediate response to global disasters. The TC includes all the necessary equipment to establish a telecommunication centre in the destroyed area within the first 72 hours of humanitarian operations. The design focuses on defining the topology of the various parts of equipment by taking into consideration factors of serviceability, functionality, human-product interaction, universal design language, energy consumption, sustainability and the interrelationship with the other containers. The concept parametric design has been implemented with SolidWorks® CAD system
Editorial: Supply Chain Management
No full textThis special issue has followed up the 2nd Olympus International Conference on Supply Chains held on October 5-6, 2012, in Katerini, Greece. The Conference was organized by the Department of Logistics of Alexander Technological Educational Institution (ATEI) of Thessaloniki, in collaboration with the Laboratory of Quantitative Analysis, Logistics and Supply Chain Management of the Department of Mechanical Engineering, Aristotle University of Thessaloniki (AUTH). During the 2-Days Conference more than 50 research papers were presented covering the following thematic areas: (i) Business Logistics, (ii) Transportation, Telematics and Distribution Networks, (iii) Green Logistics, (iv) Information and Communication Technologies in Supply Chain Management, and (v) Services and Quality. Three keynote invited speakers addressed interesting issues for the Humanitarian Logistics, Green Supply Chains of the Agrifood Sector and the Opportunities and Prospects of Greek Ports chaired Round Tables with other Greek and Foreign Scientists and Specialists
Soil Organic Carbon Assessment for Carbon Farming: A Review
No full textThis review is motivated by the urgent need to improve soil organic carbon (SOC) assessment methods, which are vital for enhancing soil health, addressing climate change, and promoting carbon farming. By employing a structured approach that involves a systematic literature search, data extraction, and analysis, 86 relevant studies were identified. These studies were evaluated to address the following specific research questions: (a) What are the state-of-the-art approaches in sampling, modeling, and data acquisition? and (b) What are the key challenges, open issues, potential advancements, and future directions needed to enhance the effectiveness of carbon farming practices? The findings indicate that while traditional SOC assessment techniques remain foundational, there is a significant shift towards incorporating model-based methods, machine learning models, proximal spectroscopy, and remote sensing technologies. These emerging approaches primarily serve as complementary to laboratory analyses, enhancing the overall accuracy and reliability of SOC assessments. Despite these advancements, challenges such as soil spatial and temporal variability, high financial costs, and limitations in measurement accuracy continue to hinder progress. This review also highlights the necessity for scalable, cost-effective, and precise SOC measurement tools, alongside supportive policies and incentives that encourage farmer adoption. Finally, the development of a “System-of-Systems” approach that integrates sampling, sensing, and modeling offers a promising pathway to balancing cost and accuracy, ultimately supporting carbon farming practices
Explainable artificial intelligence-driven geometric feature selection for enhanced field traversing efficiency prediction
No full textOptimizing the performance of agricultural machinery operations is essential for improving farm management, yielding tangible benefits in sustainability and cost savings by reducing the consumption of critical resources. However, realizing these advantages requires precise metrics to evaluate field performance. This study utilizes Field Traversing Efficiency (FTE) as a primary indicator, a metric that assesses machinery effectiveness by measuring the distance traversed during field operations. In this context, accurate FTE estimation is crucial for optimization, but remains challenging due to complex field and operational variables. This study introduces a machine learning framework to predict FTE using geometric field indices. A farm management information system was used to acquire a large dataset of agricultural fields, calculate geometric indices, and simulate operational scenarios for estimating FTE. Subsequently, data preprocessing, including outlier removal and feature selection, was performed. Seven tree-based ML models were evaluated, with XGBoost achieving both the highest predictive accuracy (R2 = 0.9402) and computational efficiency. To further interpret the best model's predictions, SHapley Additive exPlanations (SHAP) analysis was applied, providing both global and local insights into feature contributions. This analysis revealed that the Perimeter-to-Area Ratio is the most influential feature, with higher values associated with reduced FTE. Significant predictive roles were also observed for Convexity and Average Curb, with Compactness and Ellipticity showing less influence. The present interpretable insights can be utilized for actionable recommendations to optimize field designs and operational protocols, thus, offering a scalable and trustworthy path towards data-driven FTE prediction and supporting key goals of precision agriculture
Applied operations research methodologies on the optimal design and operation of construction and demolition materials reuse and recycling networks
No full textAs the growing amount of waste created by the construction industry poses severe environmental challenges, environmentally conscious construction processes have emerged as an issue of increasing importance for both the industry and society at large. The proper management of the construction and demolition (C&D) waste, which constitutes the major solid waste stream in the European Union (apart from mining and farm waste) appears to be of great merit.
Aim of this thesis is the examination of different aspects regarding C&D waste management, by the development of innovative qualitative and quantitative methodologies. The thesis consists of two parts.
In the first part, a holistic methodological framework is presented in order to manage effectively the generated waste flows from the construction and demolition activities. The decisions of the proposed framework examine different issues on C&D waste management during the entire lifecycle of construction projects and are classified in three levels: strategic, tactical and operational level.
In the second part, the development of five novel integrated models for optimizing the reverse logistics processes of end-of-life (EOL) buildings/construction sites is presented. The critical decisions of the proposed models include among others: (i) the determination of the optimal deconstruction depth for each EOL construction site before the demolition process, and (ii) the design of an effective transportation and recovery network for shipping deconstruction products and waste from deconstruction/demolition sites to potential recyclers/customers and waste disposal sites. Finally, the development of a multiple objective mathematical programming model is presented. The purpose of this decision-support optimization methodology is
the maximization of the total profit and the minimization of the required time, taking into account financial, environmental, regulatory and technological constraints.
The applicability of the proposed models is illustrated on specific case studies and interesting managerial insights regarding the behavior of the optimal solutions are presented. Finally, the main conclusions and useful directions for future research are provided.Στόχος της παρούσας διδακτορικής διατριβής είναι η προσέγγιση του προβλήματος της διαχείρισης των παραγόμενων δομικών αποβλήτων μέσω της ανάπτυξης καινοτόμων και άμεσα εφαρμόσιμων ποιοτικών και ποσοτικών μεθοδολογιών, με γνώμονα την εφαρμογή, από πλευράς των επιχειρήσεων που δραστηριοποιούνται στον κατασκευαστικό τομέα, πολιτικών διαχείρισης των δομικών αποβλήτων, φιλικών προς το περιβάλλον και το ευρύτερο κοινωνικό σύνολο.
Σε πρώτη φάση, αναπτύχθηκε ένα ολοκληρωμένο μεθοδολογικό πλαίσιο λήψης αποφάσεων για τη διαχείριση των παραγόμενων δομικών αποβλήτων από κατασκευαστικές εργασίες. Παράλληλα, για την καλύτερη αξιολόγηση των αποφάσεων, πραγματοποιήθηκε ταξινόμησή τους σε τρία ιεραρχικά επίπεδα: στρατηγικό, τακτικό και επιχειρησιακό επίπεδο.
Σε δεύτερη φάση, αναπτύχθηκαν ποσοτικά πρότυπα βελτιστοποίησης για την υποστήριξη διαδικασιών λήψης αποφάσεων στο εξεταζόμενο ερευνητικό πεδίο. Ο στόχος της δεύτερης φάσης ήταν η βελτιστοποίηση της σχεδίασης και ανάπτυξης δικτύων αντίστροφων εφοδιαστικών αλυσίδων δομικών υλικών που παράγονται στη φάση της κατεδάφισης κατασκευών που βρίσκονται στο τέλος της ωφέλιμης ζωής τους, μέσω της εφαρμογής κατάλληλων μεθόδων επιχειρησιακής έρευνας. Τα πρότυπα που αναπτύχθηκαν επιδιώκουν τη μεγιστοποίηση του συνολικού κέρδους εξετάζοντας: (α) τη διαχείριση των εργασιών κατεδάφισης και τον καθορισμό των σταδίων εκτέλεσης των εργασιών επιλεκτικής αποδόμησης, με γνώμονα τη μέγιστη δυνατή ανάκτηση δομικών υλικών, (β) την ανάκτηση συγκεκριμένων δομικών υλικών κατά την εκτέλεση εργασιών αποσυναρμολόγησης κτιρίων, (γ) τη διαχείριση των παραγόμενων δομικών υλικών (διαχείριση εντός ή εκτός εργοταξίου) και (δ) την επιλογή των τελικών παραληπτών για τα παραγόμενα δομικά υλικά. Για το σύνολο των αποφάσεων λήφθηκαν υπόψη οικονομικά, τεχνολογικά περιβαλλοντικά και νομοθετικά κριτήρια.
Τέλος, παρουσιάζεται η ανάπτυξη ενός προτύπου πολυκριτηριακού μαθηματικού προγραμματισμού (Multiple Objective Mathematical Programming), που είναι ειδική περίπτωση προβλημάτων προγραμματισμού στόχων (Goal Programming) με στόχο τη ταυτόχρονη και σταθμισμένη μεγιστοποίηση του συνολικού κέρδους του συστήματος και την ελαχιστοποίηση του απαιτούμενου χρόνου εκτέλεσης εργασιών για την ανάκτηση και διαχείριση των δομικών υλικών.
Τα κυριότερα συμπεράσματα της διατριβής προέκυψαν από την ανάπτυξη των ποιοτικών και ποσοτικών μεθοδολογιών λήψης αποφάσεων σχετικά με τη διαχείριση των παραγόμενων δομικών υλικών και παρουσιάζονται στο τελευταίο κεφάλαιο τη διατριβής
The effects of economic crisis to logistics outsourcing
No full textThe aim of this paper is the investigation of the effects that the economic crisis has on the logistics services sector in Greece. It presents and analyses the findings of a research, which, via a questionnaire, asked managers at the examined sector first to identify the effects and second the practices and approaches that the managers suggested to confront with these effects. The findings of the research revealed that the logistics' service providers have been significantly affected by the crisis and these effects have influenced all the main functional areas of the logistics management (procurement, warehousing, inventory management, transportation and distribution). Moreover, they are not optimistic about the future as they believe that the sector will be significantly decreased in the next few years and the competition will be increased. Performance measurement and optimization of their logistics' processes and functions and the decrease of the operation costs are considered to be their weapons to this battle. This research can be considered as a pilot study, as the Greek economy has been seriously affected during the global financial crisis. Worldwide, 3pl companies can use the findings of this study in order to overcome potential difficulties that might face in near future
Greening the canned peach production
No full textThe paper proposesan approach for measuring the environmental performance of canned peach production based on Lean Thinking techniques.Among the various stages of a typical production line of canned peach, peeling and pasteurizing are the most energy consuming. In these stages specific actions have been suggested and applied. Considering the findings that were observed following the implementation of these actions, the research project provided viable evidence that Lean techniquesa positive impact in the production and logistics operations
Logistics Services Sector and Economic Recession in Greece: Challenges and Opportunities
No full textThe recent economic recession in Greece has had a detrimental impact on all national business activities, with the logistics industry being one of the most affected sectors primarily due to the significant decrease in market demand for goods and services. In this regard, the aim of this research is to identify key challenges and prospects for the Greek logistics services industry stemming from the recent economic crisis era through a critical literature taxonomy, a semantic analysis of the reviewed articles, and a questionnaire-based survey involving 140 executives from the third-party logistics sector. In principal, the recent economic crisis is reported to have significantly affected logistics service providers, thus further imposing structural reforms in the industry. The reduction in operating profits of transport companies is noticeable with the onset of the economic crisis, specifically in 2016. Nevertheless, logistics executives are optimistic regarding the near future, provided that educated and informed strategic management decisions are made and inventive business practices are embraced
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