10 research outputs found

    Cross-Docking: A Proven LTL Technique to Help Suppliers Minimize Products\u27 Unit Costs Delivered to the Final Customers

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    This study aims at proposing a decision-support tool to reduce the total supply chain costs (TSCC) consisting of two separate and independent objective functions including total transportation costs (TTC) and total cross-docking operating cost (TCDC). The full-truckload (FT) transportation mode is assumed to handle supplier→customer product transportation; otherwise, a cross-docking terminal as an intermediate transshipment node is hired to handle the less-than-truckload (LTL) product transportation between the suppliers and customers. TTC model helps minimize the total transportation costs by maximization of the number of FT transportation and reduction of the total number of LTL. TCDC model tries to minimize total operating costs within a cross-docking terminal. Both sub-objective functions are formulated as binary mathematical programming models. The first objective function is a binary-linear programming model, and the second one is a binary-quadratic assignment problem (QAP) model. QAP is an NP-hard problem, and therefore, besides a complement enumeration method using ILOG CPLEX software, the Tabu search (TS) algorithm with four diversification methods is employed to solve larger size problems. The efficiency of the model is examined from two perspectives by comparing the output of two scenarios including; i.e., 1) when cross-docking is included in the supply chain and 2) when it is excluded. The first perspective is to compare the two scenarios’ outcomes from the total supply chain costs standpoint, and the second perspective is the comparison of the scenarios’ outcomes from the total supply chain costs standpoint. By addressing a numerical example, the results confirm that the present of cross-docking within a supply chain can significantly reduce total supply chain costs and total transportation costs

    An Optimization Model to Increase the Cross-Dockings Operational Utilization

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    Introducing a new version of a cross-docking assignment problem when forklifts carry bulk materials, we address an operational solution to reduce the impact of forklifts congestion in centre of terminals. We develop a mixed-integer bilinear programming model, a Tabu-search algorithm, where the main objective of the model is still to minimize the total transshipment costs, and additionally trying to minimize the weighted forklifts travelled distance (WTD) and the weighted unloading/loading labour costs at inbound and outbound doors (WLC). We hypothesize that longer WTD could shift the location of weighted forklift congestion concentration from the centre of the terminal toward the sides. We assuming four cost pattern’s distributions, all are supposed to lead high flows to doors with low labour costs, which ultimately impact the total WTD, WLC, and TTC. The proposed Tabu-search outperform CPLEX by finding a set of a diverse and high-quality solution within a reasonable computing time

    The Relationship between the Time of Endoscopy and Morbidity and Mortality Rates in Patients with Upper Gastrointestinal Bleeding

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    Background: This study was done to evaluate the relationship between the time of endoscopy in patients with upper gastrointestinal bleeding with morbidity and mortality rates of patients at the Al Zahra Hospital emergency room. Materials and Methods: In a cohort study, 1152 patients at 2014 and 2015 have been hospitalized due to gastrointestinal bleeding in Al Zahra Hospital, were selected and demographic and clinical information and day and time of endoscopy and hospital mortality and fewer deaths than a month after discharge were studied, and prognosis was analyzed in terms of day and time of endoscopy. Results: Nine hundred and seventy-three cases (84.5%) of endoscopy were performed during the working days and 179 (15.5%) were performed on holidays. Moreover, 801 cases (69.5%) of endoscopy were done in the morning and 351 cases (30.5%) were performed in the evening and night shifts. The day and time of endoscopy had no significant effect on mortality in hospital and less than a month after but hospital death in whom underwent endoscopy by fellowship was significantly higher (P = 0.004). Conclusion: Endoscopy in nonholiday and holiday days and the time of endoscopy has no significant effect on hospital mortality 1 month after discharge. However, other factors such as endoscopy by attendant or fellowship, time between admission to endoscopy, age and sex of the patients, etc., were significantly effective on in-hospital mortality and death 1 months after discharge. Also faster and sooner endoscopy cannot reduce rate of blood transfusions or reduce the length of hospital stay but faster endoscopy of patients can reduce the risk of in-hospital death

    An Optimization Model for Forklift Utilisation and Congestion Control in Cross-Docking Terminals

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    This study aims to optimize cross-docking (CD) performance and efficiency in CD assignment problems by maximising forklift utilisation inside the terminal. ‘We present a new Mixed-Integer Nonlinear programming (MINLP)’ model that considers truck-door assignment and forklift utilisation inside the airport. One objective is to enhance the quality of truck-door by minimising the total transshipment costs, including the penalty cost associated with forklift underutilisation, the total forklift travel distance cost, and the total weighted loading unloading and operator cost. Another objective is to control the forklift congestion by minimising the total number of forklifts needed to transfer products between multiple doors inside the terminal. Two algorithms, including the tabu-search and the best-local-point-finder, are proposed to accomplish these objectives. Our computational results show the advantage of the proposed algorithms over the CPLEX commercial solver

    An Optimization Model for Collaborative Logistics Among Carriers in Vehicle Routing Problems with Cross-Docking

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    Purpose Collaborative Logistics (CL) and merging operations are crucial strategies for reducing costs and improving service in transportation companies. This study proposes a model for optimizing efficiency in supply chain networks through inbound and outbound Collaborative Logistics implementation among the carriers in centralized, coordinated networks with cross-docking. Design/methodology/approach A mixed-integer non-linear programming model is developed to determine the optimal truck-goods assignment while gaining economies of scale through mixing multiple less-than-truckload (LTL) products with different weight-to-volume ratios. Unlike the previous studies that have considered Collaborative Logistics from the cost and profit-sharing perspective, the proposed model seeks to determine an appropriate form of Collaborative Logistics in the VRP. Findings This article shows that in a three-echelon supply chain consisting of a set of suppliers, a set of customers and a cross-docking terminal, partial collaboration among the inbound carriers and outbound carriers outperforms no/complete collaboration. This approach enhances the supply chain efficiency by minimizing the total transportation costs, the total transportation miles and the total number of trucks and maximizing fleet utilization. While addressing the four points, the role of collaborative logistics among the carriers was discussed. In a three-echelon SC consisting of a set of suppliers, a set of customers and a cross-docking terminal, partial collaboration among the inbound carriers and outbound carriers outperforms no/complete collaboration. Using a combination of experimental analysis and optimization process, it was recommended that managers be cautious that too much (full or complete) or no collaboration can result in SC performance deterioration. Originality/value The suggested approach enhances the supply chain efficiency by minimizing the total transportation costs, the total transportation miles and the total number of trucks and maximizing fleet utilization. While addressing the four points, the role of Collaborative Logistics among the carriers was discussed

    Sustainable Transportation in Practice: A Systematic Quantitative Review of Case Studies

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    After the COVID-19 pandemic and the spectrum of new climate change disruptions in the supply chain, a holistic approach towards sustainable transportation is needed. Sustainable transportation could benefit sustainable development from different angles; reduced traffic deaths, increased share of renewable energy, higher quality of transport-related infrastructure, increased satisfaction with public transportation, increased responsible consumption and production, and reduced fossil fuel consumption. This study is an attempt to show whereon the scholars were focused previously and where the focus needs to be more on. This study has reviewed 358 case studies and categorized them into twenty groups based on the transportation mode and eleven groups based on the authors’ primary areas of concern. Keyword analysis followed by topics modeling showed three non-overlapping trends in the cohort. The results, with a corroboratory investigation on the benefits of the United States’ infrastructure bill, were discussed in four categories: in-vehicle improvements, built-environment elements, human factors, and planning and regulations

    Sustainable Transportation in Practice: A Systematic Quantitative Review of Case Studies

    No full text
    After the COVID-19 pandemic and the spectrum of new climate change disruptions in the supply chain, a holistic approach towards sustainable transportation is needed. Sustainable transportation could benefit sustainable development from different angles; reduced traffic deaths, increased share of renewable energy, higher quality of transport-related infrastructure, increased satisfaction with public transportation, increased responsible consumption and production, and reduced fossil fuel consumption. This study is an attempt to show whereon the scholars were focused previously and where the focus needs to be more on. This study has reviewed 358 case studies and categorized them into twenty groups based on the transportation mode and eleven groups based on the authors’ primary areas of concern. Keyword analysis followed by topics modeling showed three non-overlapping trends in the cohort. The results, with a corroboratory investigation on the benefits of the United States’ infrastructure bill, were discussed in four categories: in-vehicle improvements, built-environment elements, human factors, and planning and regulations

    Drug delivery (nano)platforms for oral and dental applications: Tissue regeneration, infection control and cancer management

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    The oral cavity and oropharynx are complex environments that are susceptible to physical, chemical, and microbiological insults. They are also common sites for pathological and cancerous changes. The effectiveness of conventional locally-administered medications against diseases affecting these oral milieus may be compromised by constant salivary flow. For systemically-administered medications, drug resistance and adverse side-effects are issues that need to be resolved. New strategies for drug delivery have been investigated over the last decade to overcome these obstacles. Synthesis of nanoparticle-containing agents that promote healing represents a quantum leap in ensuring safe, efficient drug delivery to the affected tissues. Micro/nanoencapsulants with unique structures and properties function as more favorable drug-release platforms than conventional treatment approaches. The present review provides an overview of newly-developed nanocarriers and discusses their potential applications and limitations in various fields of dentistry and oral medicine

    Drug delivery (nano)platforms for oral and dental applications: tissue regeneration, infection control, and cancer management

    No full text
    The oral cavity and oropharynx are complex environments that are susceptible to physical, chemical, and microbiological insults. They are also common sites for pathological and cancerous changes. The effectiveness of conventional locally-administered medications against diseases affecting these oral milieus may be compromised by constant salivary flow. For systemically-administered medications, drug resistance and adverse side-effects are issues that need to be resolved. New strategies for drug delivery have been investigated over the last decade to overcome these obstacles. Synthesis of nanoparticle-containing agents that promote healing represents a quantum leap in ensuring safe, efficient drug delivery to the affected tissues. Micro/nanoencapsulants with unique structures and properties function as more favorable drug-release platforms than conventional treatment approaches. The present review provides an overview of newly-developed nanocarriers and discusses their potential applications and limitations in various fields of dentistry and oral medicine

    Advances in tannic acid-incorporated biomaterials: Infection treatment, regenerative medicine, cancer therapy, and biosensing

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    Polyphenol-based materials have attracted wide-spread interest from academic and industrial communities because of their unique structure and physicochemical properties. Tannic acid (TA), as a polyphenolic phytochemical with high level of galloyl groups, interacts with various substances (proteins, polysaccharides, and metals) through several modes including hydrogen bonding, hydrophobic and electrostatic interactions. Such hybrid or hybrid-like systems allow the preparation of various advanced materials with promising applications in medicine. In this review, we highlight the recent advances of TA-incorporated materials in medical applications including drug delivery, tissue engineering, treatment of infections, cancer therapy and biosensing. We believe that this review provides further investigation and development of TA as a promising natural compound to design new versatile architectures in the field of materials science
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