Notes
Traditionally, companies have been introducing approaches based on cost reductions. More recently, they are also increasingly introducing approaches that reduce their environmental impact. One of the approaches based on the reduction of costs is the so called lean approach, whereas the so called green approach strives to reduce the environmental impact. Both approaches have been extensively researched in the literature as separate phenomena, whereas only a few studies examined both approaches together. The findings have reported that, to a certain degree, both approaches are similar, but at times differ to a great extent. They are similar in that they both strive to eliminate wastes, i.e. activities that fail to add value. The present doctoral thesis focuses on the lean and green approach in the field of internal logistics. First, a systematic literature review was provided. For the modeling process, a combination of the quantitative and qualitative research approach was used. For the purpose of the study, a survey questionnaire was developed and carried out between Slovenian companies. Factor analysis was used to examine multiple internal logistics sector and modeling of structural equations. The practical part further comprised a case study. In the thesis, a conceptual framework for the evaluation of leanness or greenness of an individual internal logistics system was proposed and divided into five main areas: internal logistics processes, ergonomics and spatial planning, human resources (upper management and employees), strategic planning and results associated with internal logistics. The findings of the present doctoral thesis are multiple. In the literature review, approaches on how to deal with different ways of thinking about the possible interaction of both paradigms were proposed. Based on the literature, a strong interest on the part of the economy to integrate both areas together was identified. Furthermore, methodologies such as the factor analysis, structural equation modeling, as well as analysis of a comparison of standardized regression weights in terms of leanness and greenness also contributed interesting results. In the field of internal logistics processes have the highest weights variables unnecessary waiting and reducing procedural errors, in the field of ergonomics and spatial design, optimum allocation of workspace and sustainable building. In the field of human resources (upper management and employees), possibility of integrating employees, long-term thinking, vision, integration and evaluation of employees, strategic planning, strategy shared by all levels of the organization and other stakeholders and strategy deployment. For the area of outcomes associated with companies internal logistics have the highest weights variables constant monitoring of the results and identify the causes and consequences of the problem. The model was also applied to the Postal logistics center in Ljubljana, where the importance of variables for the five areas obtained from previous studies was examined. One of key findings is that although the company under investigation, to a large extent is a lean and green company, it has not yet followed the global trends, introduced ISO standards, acquired internationally recognized awards for leanness or greenness and so on. This would certainly have a positive impact on improving weaknesses and eliminating waste within each of the five areas. By introducing lean and green management practices, an opportunity for Slovenian as well as foreign companies was identified to competently respond to increasingly higher market expectations. The thesis represents an important contribution to researchers and professionals from the industry. For researchers, mainly because it is, to the best of my knowledge, the first study that simultaneously addresses both approaches and for the industry, because it primarily provides an insight into new trends and contributes to internal logistics.