Locker box location planning under uncertainty in demand and capacity availability

In this paper, we address the location of locker boxes in the last-mile delivery context under uncertainty in demand and capacity. The problem is modeled as an extension of the capacitated facility location problem, in which a fixed number of facilities has to be opened, choosing among a set of potential locations. Facilities are characterized by a homogeneous capacity, but a capacity reduction may occur with a given probability. The uncertainty in demand and capacity is incorporated through a set of discrete scenarios. Each customer can be assigned only to compatible facilities, i.e., to facilities located within a given radius from the individual location. The goal is to first maximize the total number of customers assigned to locker boxes, while, in case of a tie on this primary objective, a secondary objective intervenes aiming at minimizing the average distance covered by customers to reach their assigned locker box. A stochastic mathematical model as well as three matheuristics are presented. We provide an extensive computational study in order to analyze the impact of different parameters on the complexity of the problem. The importance of considering uncertainty in input data is discussed through the usage of general stochastic indicators from the literature as well as of problem specific indicators. A real-world case related to the City of Turin in Italy is analyzed in detail. The benefit achievable by optimizing locker box locations is discussed and a comparison with the current configuration is provide

‘Chemlali Mhassen’: New olive cultivar derived from crossbreeding program in Tunisia with high oil quality and productivity

The new olive cultivar ‘Chemlali Mhassen’ was derived from the autopollination of the Tunisian oil cultivar ‘Chemlali Sfax’. The main morphological differences between the two cultivars were observed on the endocarp (symmetry, position of maximum diameter, apex, base and surface). On the agronomic plan, this cultivar is distinguishable from the original cultivar due to its medium earliness of bearing (4 years), medium alternate bearing (0.44), early ripening, moderate sensitivity to verticillium and its high olive production per tree (7.7 kg). Concerning oil quality, ‘Chemlali Mhassen’ had higher performances than the original cultivar for oleic acid content (70 to 77 %) and lower contents for palmitic acid (9.2 to 11.5 %) and linoleic acid (9.3 to 14.7 %). Similar performances were recorded between the new and the original cultivars for rhizogenesis behavior and pollen compatibility

A critical assessment of the technical and vocational education and training programme for the Libyan chemical industry

Libya traditionally suffers from a shortage of skilled manpower. A network of Technical and Vocational Education and Training (TVET) institutions were introduced in Libya, for the purpose of enhancing the supply of skilled manpower needed for the manufacturing industry and the national socio-economic development plans. The shortage of qualified manpower, such as engineers and technicians, skilled workers, is largely attributable to the failure of TVET to supply the country with its requirements of trained manpower in scope of manufacturing industry. The assumption behind this research is that Higher Education Institutions (HEIs) in general and TVET in particular suffer from a lack of appropriate planning mechanisms and procedures for the linking TVET with manufacturing industry. This study was exploratory and descriptive in nature and used a quantitative research method. This study presents initial results from a survey of students at HEIs; and engineers and technicians at a manufacturing industry. It investigates their perception regarding TVET programmes as well as work-related issues in Libya. Some of the research key findings are: there is a substantial mismatch between the outcome of TVET and the exact requirements of the Libyan manufacturing industry; most of the TVET suffer from limited human and physical resources, and the unavailability of a framework for the development of TVET and to assist in organising the link and narrow the gap between Libyan TVET institutions and chemical manufacturing industry. On the bases of the data analysis and the findings, recommendations for a framework to strengthen the link between TVET providers and manufacturing sector has been put forward to be used by educational planners in Libya in establishing or improving existing TVET. Some suggestions are also made for further research to address the issue of acceptance of industrial and vocational work and related influencing factors.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Prevalence and risk factors of low back pain among undergraduate students of a sports and physical education institute in Tunisia

Introduction: For obvious reasons, athletes are at greater risk of sustaining a lumber (lower) spine injury due to physical activity. To our knowledge, no previous studies have examined the prevalence of low back pain (LBP) in a Tunisian sports and physical education institute.Aim: To assess the prevalence of LBP in different sports among students studying in a sports and physical education institute in Tunisia, to determine the causes of the injuries, and to propose solutions.Methods: A total of 3,379 boys and 2,579 girls were studied. A retrospective cross-sectional survey was conducted on a group of students aged 18.524.5 years at the Higher Institute of Sport and Physical Education of Sfax to estimate the prevalence of LBP and its relation to the type of sports. Data on age, weight, height, smoking, and the sport in which the student was injured in the low back were collected from the institute health service records from 2005 until 2013.Results: LBP was reported by 879 of the 5,958 study participants (14.8%). The prevalence of LBP was significantly higher (pB0.001) in females (17.6%) than in males (12.5%). LBP prevalence did not differ by body mass index or smoking habit (p0.05). The sports associated with the higher rates of LBP were gymnastics, judo, handball, and volleyball, followed by basketball and athletics.Conclusion: LBP is frequent among undergraduate students of a sports and physical education institute in Tunisia. It is strongly associated with fatigue after the long periods of training in different sports. Gymnastics, judo, handball, and volleyball were identified as high-risk sports for causing LBP.Keywords: low back pain; sports students; sports training; risk factor

A critical assessment of the technical and vocational education and training programme for the Libyan chemical industry

Libya traditionally suffers from a shortage of skilled manpower. A network of Technical and Vocational Education and Training (TVET) institutions were introduced in Libya, for the purpose of enhancing the supply of skilled manpower needed for the manufacturing industry and the national socio-economic development plans. The shortage of qualified manpower, such as engineers and technicians, skilled workers, is largely attributable to the failure of TVET to supply the country with its requirements of trained manpower in scope of manufacturing industry. The assumption behind this research is that Higher Education Institutions (HEIs) in general and TVET in particular suffer from a lack of appropriate planning mechanisms and procedures for the linking TVET with manufacturing industry.This study was exploratory and descriptive in nature and used a quantitative research method. This study presents initial results from a survey of students at HEIs; and engineers and technicians at a manufacturing industry. It investigates their perception regarding TVET programmes as well as work-related issues in Libya. Some of the research key findings are: there is a substantial mismatch between the outcome of TVET and the exact requirements of the Libyan manufacturing industry; most of the TVET suffer from limited human and physical resources, and the unavailability of a framework for the development of TVET and to assist in organising the link and narrow the gap between Libyan TVET institutions and chemical manufacturing industry. On the bases of the data analysis and the findings, recommendations for a framework to strengthen the link between TVET providers and manufacturing sector has been put forward to be used by educational planners in Libya in establishing or improving existing TVET. Some suggestions are also made for further research to address the issue of acceptance of industrial and vocational work and related influencing factors

Solitary wave solutions of the Vakhnenko–Parkes equation

In this paper, two solitary wave solutions are obtained for the Vakhnenko–Parkes equation with power law nonlinearity by the ansatz method. Both topological as well as non-topological solitary wave solutions are obtained. The parameter regimes, for the existence of solitary waves, are identified during the derivation of the solution