Michał Kłodawski

Implementation of the model of proecological transport system

Paper presents assumptions to build simulation model allowing computational experimentation and inference on impact of various factors on transport modal split and the impact that transport has on environment. It presents a general mathematical model of environmentally friendly transport system and characterizes particular elements of this model. The structure of transport network is mapped with a graph. The characteristics describing elements of this structure, vehicles, and characteristics of harmful compounds emission are given. Model will be implemented in PTV VISUM environment – a tool supporting planning of transport processes as well as analysis and designing of transport systems. The model of proecological transport system developed in PTV VISUM will consist of model of demand for both passenger and freight transport, and model of transport network cooperating with various means of transport. Road and rail vehicles for passenger and freight transport are characterized and divided into groups according to type of fuel and harmful emission. The demand for transport services and emission of exhaust gases components are reflected in model of proecological transport system of Poland. The last part of paper presents a sample of preliminary research on estimating emission from particular type of vehicle.

Technical and organizational conditions of designing warehouses with different functional structures

The article presents a discussion on designing warehouse facilities and processes as a part of logistics systems. The main technical and organizational conditions of designing and modelling warehouses as well as internal and external factors influencing warehouse operation are presented. The stochastic nature of these factors is indicated. In the next part, a six-piece model of the warehouse facility is presented and discussed. The model embraces spatial conditions of the object and hierarchical division of space for functional reasons, internal transport subsystem with its resources, warehousing process and a set of organizational assumptions for modelling and designing. Typical elements of warehousing process, classification of warehouses due to their functions and tasks, functional classification of warehouse facilities, technological and organizational conditions of designing warehouse facilities, warehouse designing loop, the determinants of warehouse designing, the elements of the model of a warehouse, functional structure of a warehouse, warehousing process, internal transport system, logistics task, work organization rules and informatics system are presented in the paper.

Decision making strategies for warehouse operations

The paper presents issues related to design and organization of warehouse processes. Draws attention to problems of modelling logistics facilities and processes occurring in them. Paper also points out the essence of correct operation of warehouses and associated with this risks for supply chain. Warehouse processes have been properly defined and divided into smaller components, like: phases of process, activities, sets of procedures, procedures or working movements. Paper presents various possible configurations of warehouse processes, which were named as warehouse strategies. Warehouse process strategy is a part of warehousing. It determines the sequence of warehouse operations. These operations are related to internal transport, cargo form transformation and cargo buffering. In paper it is noted that the warehouse strategy depends on the several technical and organizational factors and is associated with a certain probability. This probability can be estimated based on data analysis concerning logistics processes in the specified warehouse facility. As shown in case study, appropriate selection of warehouse strategies determines possibility of fulfilling customer order in time and costs that are acceptable for him.

Selected Aspects of Warehouse Process Control and the Quality of Warehouse Services

The warehouse is a node element of logistics network affecting cost and reliability of material flows and determining logistics services quality. Mechanisms of warehouse process control and the ability to shape warehouse service potential have an impact on its readiness to provide services at a required quality level. This potential includes material handling technologies, storage technologies and controlling procedures. The paper discusses influence of selected mechanisms of warehouse control on its efficiency and readiness (reliability). It presents the principles of modelling control mechanisms and the possibility of including them in the tools for warehouse processes management.

Chosen aspects of simulation model to designing pro-ecological transport system

Paper presents simulation model of pro-ecological transport system (PTS). Model allows computational experimentation and inference on transport modal split and emission of pollution in a national scale. The characteristics describing infrastructure, vehicles, and harmful compounds emission are given. Model is implemented in VISUM – a tool supporting planning of transport processes as well as analysis and designing of transport systems. The demand for transport services and emission of exhaust gases components are reflected in model of pro-ecological transport system of Poland. In particularly, Representation of model of pro-ecological transport system, transport sub-systems and segments of demand in freight transport in simulation model of PST, detailed assumptions of onboard measurements for Mercedes C200, detailed results of on-board measurements of pollutants, CO2 emission in function of instantaneous velocity and acceleration, representation of pollutants emitted by freight transport in Poland, as well general assumptions for designing simulation model of pro-ecological transport system and material and passenger flows distribution and the pollution emission are presented in the paper.