in today’s competitive transportation systems, passengers search to find traveling agencies that are able to serve them efficiently considering both traveling time and transportation costs. in this paper, we present a new model for the traveling salesman problem with multiple transporters (tspmt). in the proposed model, which is more applicable than the traditional versions, each city has diffe...

this paper proposes a new mathematical model for designing and planning postal parcels carriage and postal networks. the objective of postal network designing is to determine the location, size and connection between the postal stations in a city, province or country. in this paper, a kind of multiple locations-allocations hub problem with limited capacity in collecting, distributing and broadc...

In this article, we propose a special case of two-echelon location-routing problem (2E-LRP) in cash-in-transit (CIT) sector. To tackle this realistic problem and to make the model applicable, a rich LRP considering several existing real-life variants and characteristics named BO-2E-PCLRPSD-TW including different objective functions, multiple echelons, multiple periods, capacitated vehicles, dis...

In this paper, we aim at developing a model for option pricing to reduce the risks associated with Ethiopian commodity prices fluctuations. We used the daily closed Unwashed Lekempti grade 5 (ULK5) coffee and Whitish Wollega Sesame Seed Grade3 (WWSS3) prices obtained from Ethiopia commodity exchange (ECX) market to analyse the prices fluctuations.The natures of log-returns of the prices exhibit a...

We study market games with multiple posts per commodity. We provide some facts that characterize prices of commodities across posts and show the following results: (i) As the number of agents increases, the price variability across posts for a commodity becomes smaller and it becomes zero when the number of agents becomes infinite, irrespectively of the distribution of characteristics in the ec...

Since China has been Iran's most important trading partner in recent years, the present study has attempted to investigate the effect of bilateral real exchange rate fluctuations on the trade relationship between Iran and China during the period 1992-2017. To investigate this relationship, the business data in the export and import sectors were divided into 15 major commodity segments, and the ...

INTRODUCTION Since the introduction of a regionalized trauma system in Quebec in 1993, patient loads at level I trauma centres have been increasing gradually. We aimed to investigate the type of patient presenting to 4 tertiary trauma centres in Quebec, the nature of their injuries and whether there was a need to modify triage protocols. METHODS The study consisted of a review of major trauma...

We analyze the coordinated motion of a group of nonholonomic vehicles that are controlled in a distributed fashion to exhibit flocking behavior. This behavior emerges from aggregating the control actions of all group members; it is not imposed by some centralized control scheme. Each vehicle is locally controlled by a combination of a potential field force and an alignment force. The former con...