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Open access

Rabeb Kammoun

Abstract

Maritime transportation for Tunisia plays an important role in trade exchange with other countries. Therefore, the objective of this paper is to measure the efficiency scores of 7 seaports in Tunisia by applying the Stochastic Frontier Analysis (SFA) with Cobb-Douglas production function and Data envelopment analysis (DEA) with CCR and BCC models. The annual data collected cover the 2007-2017 period for each port. Thus, the sample size for the analysis comprises a total of 77 observations. The empirical result shows that the total average scores of operating efficiency scores were DEA-BCC (0.746) >SFACD (0.536)>DEA-CCR (0.334) from 2007 to 2017. Given these results, the port of Gabes can be considered as the best efficient port in the 3 models (DEA-BCC, DEA-CCR and SFA-CD).

Open access

Eftihia Nathanail, Lambros Mitropoulos, Ioannis Karakikes and Giannis Adamos

Abstract

The salient scope of this paper is to enable the knowledge and understanding of urban freight transportation and provide guidance for implementing sustainable policies and measures in a city. To achieve this goal, an evaluation framework for city logistics policies and measures is developed, which demonstrates the complexity of urban freight transportation systems, through selected performance indicators, taking into account divergent stakeholders’ interests, conflicting business models and operations. Evaluation follows a hierarchical process; sustainability disciplines (economy and energy, environment, transportation and mobility, society), applicability enablers (policy and measure maturity, social acceptance and users’ uptake), multiple criteria and indicators, capturing the lifecycle impact of policies and measures and multiple stakeholders. Apart from the multicriteria context, the framework embeds methodologies, including, Impact Assessment, Social Cost Benefit Analysis, Transferability and Adaptability, and Risk Analysis. To demonstrate its applicability a case study is set for the City of Graz assessing the establishment of an Urban Consolidation Center. Results show that there is an overall improvement of 2.2% in the Logistics Sustainability Index when comparing before and after implementation cases of the Urban Consolidation Center.

Open access

Klemen Prah, Abolfazl Keshavarzsaleh, Tomaž Kramberger, Borut Jereb and Dejan Dragan

Abstract

The paper addresses the optimal bus stops allocation in the Laško municipality. The goal is to achieve a cost reduction by proper re-designing of a mandatory pupils’ transportation to their schools. The proposed heuristic optimization algorithm relies on data clustering and Monte Carlo simulation. The number of bus stops should be minimal possible that still assure a maximal service area, while keeping the minimal walking distances children have to go from their homes to the nearest bus stop. The working mechanism of the proposed algorithm is explained. The latter is driven by three-dimensional GIS data to take into account as much realistic dynamic properties of terrain as possible. The results show that the proposed algorithm achieves an optimal solution with only 37 optimal bus stops covering 94.6 % of all treated pupils despite the diversity and wideness of municipality, as well as the problematic characteristics of terrains’ elevation. The calculated bus stops will represent important guidelines to their actual physical implementation.

Open access

Vlado Popović, Borut Jereb, Milorad Kilibarda, Milan Andrejić, Abolfazl Keshavarzsaleh and Dejan Dragan

Abstract

Improvements in battery technology make electric vehicles more and more suitable for the use as electricity storages. Many benefits could be achieved by using electric vehicles for storing electricity in their batteries. This paper talks about the idea of electric vehicles as electricity storages in electric power systems. The idea has a great number of supporters, but also a significant part of the professional community believes that is unfeasible. This paper is not classified in either side and strives to give a realistic picture of this idea. For this purpose, findings from papers published in scientific journals are mainly used. There is also some information from websites, mainly for some technical issues. Partly, the opinions of the authors are present. Specificities of EVs and EPSs that enabled the birth of this idea are explained along with proposed concepts through which the idea can be implemented. Keeping with the vehicle to grid concept, issues about the implementation of the idea are considered. Achievements in the practical realization of the idea are also presented.

Open access

Jakob Marolt and Tone Lerher

Abstract

Our research objective is to lower intralogistics costs by minimizing the number of shuffling operations in a steel plant company commercial warehouse. The process of dispatching products consists of retrieving set of steel bar (SSB) from a floor stored stack or a special stacking frame by an overhead crane. To retrieve a targeted merchandise all SSB above targeted must be reshuffled. Proper assignment of storage locations is a key logistics problem for efficient order picking. We are comparing two heuristics, that do not require information of dispatching sequence of any stored products. We simulated the problem at hand with both methods. Our objective is to count the number of reshuffles using each heuristic on randomly generated examples and decide which is better in the long run. Our problem has similarities with storage assignment of steel plates or steel coils for minimization of reshuffling operations. The problem is also comparable to storage assignment of containers in a container yard. In our case we are dealing with a special stacking configuration of products, that demands different approach. We want to demonstrate which heuristic should be used in companies that lack necessary storage information infrastructure.

Open access

Funsho Idowu Obakemi

Abstract

Road traffic safety among socioeconomic issues has become the major concern across the globe due to rise in road crashes attributed largely to human factor. This study tends to address attitudinal behavior of road users towards road ethics in Ilorin metropolis-Nigeria; covering both driver and motorcyclists and perception of motorists on road traffic enforcement agent. Questionnaire was employed as survey tools. Ordered logistic model were used to analyse the data on attitude of motorists and road traffic laws enforcement agents. About 87% of the 440 administered questionnaire were returned valid. A 3-model analysis was carried out and the findings showed that the attitude of the motorists, road traffic law enforcement agents and demographical index (gender, age and education) correlated with, and influence compliance with road traffic laws.

Open access

Joanna Piepiórka-Stepuk

Abstract

The paper presents results of analysis of turbidity changes in washing solutions and the quantity of solid particles present in them during regeneration under various temperature conditions. Three solutions taken from breweries after the process of washing brewhouse equipment in the CIP system were evaluated. The results were subjected to statistical analysis, to define the functions that characterize the changes of the tested parameters in relation to time and temperature. The results showed that the tested solutions have different favourable conditions for their regeneration. It has also been shown that the character of changes in solutions in the regeneration process is more advantageously determined on the basis of turbidity tests of solutions.

Open access

Petr Savinykh, Vladimir Kazakov, Nikolaj Czerniatiev, Svietlana Gerasimova, Wacław Romaniuk and Kinga Borek

Abstract

Analysis of patent solutions and research of scientific-research literature in the field of grain processing with technical devices, e.g. kneaders in relation to the quality and digestibility in feed doses of the obtained syrup for the development of beef and dairy cattle was performed. Assumptions of the development trend of feed production, new technologies based on grain, which allow improvement of the quality of feed and reliability of technological lines of animal nutrition, reduce energy consumption, reduce losses were presented. In this regard, reduction of the cost of producing feed compared for example to the production of fodder beet or sugar beet from 1.5 to 2 times is possible.

Open access

Sebastian Kot, Irina Onyusheva and Katarzyna Grondys

Abstract

The research aimed to assess Supply Chain Management (SCM) in small and medium enterprises in Kazakhstan and Poland, and, more specifically, identify similarities and differences in the approach to the SCM concept in selected countries. The research methodology was based on ANOVA analysis comparing samples of contemporary SMEs operating in Poland and Kazakhstan. Primary data was collected using the CAWI quantitative method and then studied using the ANOVA statistical data analysis method. The research results demonstrated similar involvement in the implementation of the concept with significant differences in some areas, such as cost reduction and focus on end customers. The concept of Supply Chain Management is a very common subject of theoretical and practical analysis. Even though research efforts in this area indicate the positive effects of the implemented concept, most of them concern large organisations. The research results showed similar involvement in the implementation of the concept, although significant differences were found in selected areas, such as cost reduction and focus on end customers.