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Military logistics is a complex process where response times, demand uncertainty, wide variety of material references, and cost-effectiveness are decisive for combat capability. The demanding flexibility can only be achieved by improving supply chain management (SCM) to minimize lead times. To cope with these requirements, lean thinking can be extended to military organizations. This research justifies and proposes the use of lean methodologies to improve logistics processes with the case study of a military unit. In particular, the article presents the results obtained using value stream mapping (VSM) and value stream design (VSD) tools to improve the order processing lead time of spare items. The procedure starts with an order generation from a military unit that requests the material and ends before transportation to the final destination. The whole project was structured, considering the define-measure-analyze-improve-control (DMAIC) problem-solving methodology. The results show that the future state map might increase added-value activities from 44% to 70%. After implementation, it was demonstrated that the methodology applied reduced the lead-time average and deviation up to 69.6% and 61.9%, respectively.Appl. Sci. 2020, 10, 106 2 of 17 in the supply chain reliability by synchronizing each element internally and externally, forecasting the demand and managing inventories and assets efficiently.To minimize response times and to assure the required flexibility avoided wastes, the lean philosophy can be extended to supply chain management in military organizations. For example, the United States Department of Defense (DoD) has been working intensively together with service providers and supporting contractors to introduce and apply lean principles into their organizations to optimize internal lead times [7]. The origin of lean philosophy is generally attributed to the practices developed from the TPS or Toyota Production System [8,9], pioneered by Taiichi Ohno [10] and Shigeo Shingo [11]. Their lean principles related to philosophy, processes, people, partners, and problem-solving allow organizations the implementation of lean thinking at different levels. Moreover, TPS has influenced not only manufacturing concepts but also supply chain management ones [12][13][14]. The concept of lean supply is described in [15,16] as an operating attitude that needs to be changed in relation to suppliers so that the effect of associated costs to non-perfect processes will not be limited to the location of the execution. This approach targets long-term customer satisfaction. Thus, supply chain optimization is possible according to the three main TPS goals: best quality, lowest cost, and shortest lead-time, which are achieved by continuous improvement and increasing operations' added value.This work evaluates the use of lean methodologies and their application to military logistics functions, focusing on supply chain management processes for spare parts. We present a case study to improve military material order processing pr...

The usage of recycled polymers for industrial purposes arises as one of the most promising methods of reducing environmental impact and costs associated with scrapping parts. This paper presents a systematic study of the dimensional stability of a raw and 100% recycled polypropylene subjected to realistic environmental conditions occurring along its working life. The component studied is an internal part of an induction hob assembly. Industrial samples manufactured with both materials, in the same mold, and in the same injection machine, are subjected to ejection conditions, storage conditions (50 °C), and extreme performance conditions (80 °C). Induced dimensional changes are registered and analyzed using a coordinate measuring machine, and a tactile sensing probe. To verify the process capability of the samples manufacturing, Cp and Cpk values are calculated to evaluate the suitability of the recycled material as an alternative. Results conclude that, although the use of recycled material implies slight differences in terms of dimensional stability due to the changes induced in the polymer structure, these differences are not significant enough to affect the injection process capability. Therefore, recycling arises as one effective method to reduce both overruns associated with the consumption of raw polypropylene material and its environmental impact.

This paper presents a new verification procedure for articulated arm coordinate measuring machines (AACMMs) together with a capacitive sensor-based indexed metrology platform (IMP) based on the generation of virtual reference distances. The novelty of this procedure lays on the possibility of creating virtual points, virtual gauges and virtual distances through the indexed metrology platform’s mathematical model taking as a reference the measurements of a ball bar gauge located in a fixed position of the instrument’s working volume. The measurements are carried out with the AACMM assembled on the IMP from the six rotating positions of the platform. In this way, an unlimited number and types of reference distances could be created without the need of using a physical gauge, therefore optimizing the testing time, the number of gauge positions and the space needed in the calibration and verification procedures. Four evaluation methods are presented to assess the volumetric performance of the AACMM. The results obtained proved the suitability of the virtual distances methodology as an alternative procedure for verification of AACMMs using the indexed metrology platform.

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This paper presents an overview of the literature on tangential composite and radial composite gear inspection. It demonstrates -by dealing with their origins and key milestones in their history and development -the important role that inspections play in terms of the functional nature of the gears concerned. This comprehensive consideration of the subject also attempts to demonstrate how the lack of clear guidelines and standards designed to unify the criteria applied to testing, the interpretation of results and calibration of equipment, along with the number of simultaneous variables involved in trials of this type, leads to doubts (including with respect to the actual standards concerned) as to whether these tests are valid, or instead accepted only has partial validations. Even so, the repeatability of the experimental data demonstrates not only their metrological potential, with respect to functionality, but also the fact that they are both effective and original.

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