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The purpose of this study is to evaluate the geometric quality of small diameter holes in parts printed by direct metal laser sintering (DMLS) technology. An in-process optical inspection method is proposed and assessed during a pilot study. The influence of the theoretical hole diameter assumed in a computer-aided design (CAD) system and the sample thickness (hole length) on the hole clearance was analyzed.

The samples are made of two different materials: EOS MaragingSteel MS1 and aluminium alloy EOS Aluminium consisted of straight through holes of different diameters and lengths. Dimensional and shape accuracy of the holes were determined with the use of the image processing software and the computer analysis of two-dimensional (2-D) images. The definition of the equivalent hole diameter was proposed to calculate the hole clearance. Feret’s diameters were determined for the evaluation of the shape accuracy.

The dependency between the equivalent hole diameter and the theoretical diameter was approximated by the linear function for a specific sample thickness. Additionally, a general empirical model for determining the hole clearance was developed, allowing for calculating the equivalent hole diameter as a function of a sample thickness and a theoretical hole diameter.

Developed functions can be used by designers for a proper assignment of a hole diameter to achieve the required patency. The relevant procedures and macros based on proposed empirical models can be embedded in CAD systems to support the designing process.

The analysis of the geometric quality of the holes in parts printed by DMLS was based on the computer analysis of 2-D images. The proposed method of assessing the shape accuracy of straight through holes is relatively cheap, is widely available and can be applied to the features of other shapes produced by three-dimensional printing.

The purpose of this paper is to investigate ways to reduce the average amount of exceeded guaranteed service time for external trucks at Deepwater Container Terminal Gdańsk Sp z o.o. (DCT Gdańsk) via dosing the gate activities, in particular IN-Gate entry process, of trucks carrying import/export/transit containers.

A Six Sigma methodology with the define, measure, analyze, improve, and Control (DMAIC) methods along with the SIPOC chart, cause and effect diagram, scatterplot, benchmark and brainstorming and finally multi-voting tool are used as analyses tools in this research.

DCT Gdańsk reorganized and modernized the gate operations. Gate reorganization and modernization include streaming line traffic at the gates, external parking lot optimization, implementation of dedicated supporting software and installation of dedicated CCTV cameras to provide 24 h live view. During gates development, the external truck service times data were collected and analysed. The obtained materials concerned the measurement of the average truck turnaround time before and after the implementation of the improvements.

The proposed approach of reducing the average amount of exceeded guaranteed service time of external trucks at the container terminal is unique and relatively cheap mainly due to organizational changes with some widely available low-cost investments and can be applied on a different scale to other container terminals or to transport and logistics companies.