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The reliability of thick film multilayer systems, based on palladium‐silver conductors, and obtained from several suppliers, is evaluated. A test structure is presented and the impact of different parameters, such as humidity, temperature, voltage bias and presence of overglaze, on the data is discussed. A SEM analysis of the failed samples allows identification of the failure mechanisms as due to flaws (pinholes and inclusions) in the dielectric.

A new method of studying the accelerated ageing of interconnection materials is applied to a high‐stability thick film resistor system (the Du Pont HS‐80 system). The new method, referred to hereafter as the in‐situ method, allows measurement of the electrical resistance of a thick film resistor to a resolution of a few ppm during accelerated ageing. With the in‐situ technique, the electrical resistance measurements are performed at the elevated ageing temperature during the ageing treatment, whereas with the conventional ageing method the resistance measurements are carried out at room temperature, between subsequent annealing steps. The measuring resolution obtainable with the in‐situ method is orders of magnitude better than with the conventional method. The ageing kinetics can therefore be studied on a shorter time scale and in greater detail than with the conventional method. In this paper, the authors use the in‐situ method to study the accelerated ageing of the Du Pont HS‐80 thick film resistor system, encapsulated with a proper glaze. It will be shown that kinetics of the resistance drift observed in this system cannot be described by an Arrhenius‐type equation. The ageing data can only be interpreted in terms of a kinetic model incorporating a spectrum of activation energies for the ageing process. Such a model is given, and is shown to provide a good explanation of the observed ageing behaviour. The physical process that causes the observed ageing is most probably diffusion of silver from the contacting terminals into the amorphous matrix of the thick film resistor.

The solderability of a material is considered as the ability of the surface to be wetted by solder, and the rate at which this process occurs. The solderability of thick film conductors based on palladium—silver, by Pb/Sn/Ag solder, was evaluated using a meniscograph. The influence of the composition of the conductor and that of the temperature of the solderbath on the solderability were measured. The usefulness of meniscographic data for the production line is indicated by showing the relation between the production data, reported as the rate at which a full automated solder machine is operated, and the meniscographic results.

The evolution of today's high speed electronic systems has resulted in the need for modules which are able to provide all chip‐to‐chip interconnection with very fine top level and buried conductor traces, and a dielectric with a very dense via grid pattern. As standard thick film technology is capable of pitches only down to 250 µm, new photoimageable thick film pastes have been developed in order to achieve a higher resolution. These materials allow one to combine the advantages of screen printing as a deposition technique with photolithography for the patterning. The image is produced by exposing the printed paste through a photomask to define either lines or vias, so that a very high resolution (50 (µm pitch), similar to that available in MCM‐D or MCM‐L, can be achieved. This paper describes the processing of the photoimageable dielectric and conductor pastes. As an example of the capability of this technology, a module for electro‐optical interconnection is presented.

In this paper, we will address privacy and trust issues that arise in more advanced software systems. Though a lot of information is currently available in electronic form, not all of it should widely be accessible to everybody. The involved parties need full control on how their data are used and who has access. If the system consists of autonomous software agents, this problem requires extra attention and new working principles. We illustrate this in the case of a communication platform for multimodal transport. The major aim of the communication platform is to enhance exchanging information and to ultimately improve organisation/collaboration within the transport sector. A better informed view of the transport sector will facilitate better considered decisions for users of the communication platform. The software system merits credibility by accurately modelling all the relevant real world interactions of potential users of the system. We opted for a connectivity solution in which software agents act as representatives of the parties involved. All agents can be equipped with human‐like skills and qualities such as intelligence, autonomy, and the ability to cooperate, coordinate and negotiate. We demonstrate how cooperation between parties can be achieved while respecting their sensitivity concerning information.

The purpose of this paper is to characterize monofloral and heterofloral honey samples (chestnut, lavandula, acacia and sunflower) from different regions of Turkey according to their physicochemical (moisture content, acidity, ash, sucrose, reducing sugar and hydroxymethylfurfural content) and biochemical properties to compare regional and species differences that are thought to contain different types of plant sources.

Physicochemical investigations were performed according to AOAC methods. Mineral analysis and volatile analysis were performed by using atomic absorption spectrometry and GC–MS, respectively. Antimicrobial activities of honey samples were evaluated based on disc diffusion method and minimum inhibition concentration (MIC) values. The assays followed to determine total phenolic content and antioxidative and activities are spectrophotometric methods.

The obtained values of physicochemical parameters are among the values that can be accepted according to legal regulations. The most abundant mineral was potassium, which made up 81 per cent of the total mineral content, ranging between 165.7 and 301.6 mg/kg. A total of 87 different volatile components, some of which are highlighted in the literature to have antimicrobial and antioxidant effects, were detected. The maximum phenolic content, antioxidant activity against DPPH radical and ferric reducing ability were detected in the chestnut honeys. All tested honeys showed antimicrobial activity with MIC values between 6.25 and 50 µg/mL.

The present study has the feature of being a large study in terms of the region from where honey samples were selected and choice of analysis. The values obtained from physicochemical parameters reveal that the honeys from related region can be consumed with confidence. The biological properties found in honeys make them products of high added value and excellent quality.

This study aims to propose a novel method for the conflict detection and eradication of autonomous vehicles which has predetermined routes to establish multi pickup and delivery tasks according to task priorities and vehicle capacity status on each pickup and delivery nodes in assembly cells in the automotive production.

In the designed system, the routing of autonomous vehicles (AVs) and scheduling of pickup and delivery tasks are established in production logistics. Gantt chart is created according to vehicle routes, and conflicts are detected using the proposed conflict-sweep algorithm. The proposed conflict-solving algorithm eliminates conflicts on intersections and roads by considering vehicle routes and task priorities.

In many production systems, there is a need to obtain flexible routes in each pickup delivery task group that changes during day, week, etc. Proposed system provides remarkable advantages in obtaining conflict-free routes for pre-scheduled multi transport tasks of vehicles by considering efficiency in production systems.

A novel method is proposed for the conflict detection and eradication of AVs. Proposed system eliminates conflicts on intersections and roads by considering pre-planned vehicle routes for a fleet of heterogeneous AVs. Unlike most of the other conflict-free algorithms, in which conflicts are solved between two points, proposed system also considers multi pickup and delivery points for AVs. This is pioneering paper that addresses conflict-free route planning with backhauls and scheduling of multi pickup and delivery tasks for AVs.

The purpose of this study is use a bibliometric analysis to explore the relational nature of knowledge creation in WFM in operations. Companies live under constant pressure to find the best ways to plan their workforce, and the workforce emangement (WFM) is one of the biggest challenges faced by managers. Relevant research on WFM in operations has been published in a several range of journals that vary in their scope and readership, and thus the academic contribution to the topic remains largely fragmented.

To address this gap, this review aims to map research on WFM in operations to understand where it comes from and where it is going and, therefore, provides opportunities for future work. This study combined two bibliometric approaches with manual document coding to examine the literature corpus of WFM in operations to draw a holistic picture of its different aspects.

Content and thematic analysis of the seminal studies resulted in the extraction of three key research themes: workforce cross-training, planning workforce mixed methods and individual workforce characteristics. The findings of this study further highlight the gaps in the WFM in operations literature and raise some research questions that warrant further academic investigation in the future.

Likewise, this study has important implications for practitioners who are likely to benefit from a holistic understanding of the different aspects of WFM in operations.

This study develops a model and algorithm to solve the decentralized resource-constrained multi-project scheduling problem (DRCMPSP) and provides a suitable priority rule (PR) for coordinating global resource conflicts among multiple projects.

This study addresses the DRCMPSP, which respects the information privacy requirements of project agents; that is, there is no single manager centrally in charge of generating multi-project scheduling. Accordingly, a three-stage model was proposed for the decentralized management of multiple projects. To solve this model, a three-stage solution approach with a repeated negotiation mechanism was proposed.

The experimental results obtained using the Multi-Project Scheduling Problem LIBrary confirm that our approach outperforms existing methods, regardless of the average utilization factor (AUF). Comparative analysis revealed that delaying activities in the lower project makespan produces a lower average project delay. Furthermore, the new PR LMS performed better in problem subsets with AUF < 1 and large-scale subsets with AUF > 1.

A solution approach with a repeated-negotiation mechanism suitable for the DRCMPSP and a new PR for coordinating global resource allocation are proposed.

Human resources are one of the most important and effective elements for companies. In other words, employees are a competitive advantage. This issue is more vital in the supply chains and production systems, because of high need for manpower in the different specification. Therefore, manpower planning is an important, essential and complex task. The purpose of this paper is to present a manpower planning model for production departments. The authors consider workforce with individual and hierarchical skills with skill substitution in the planning. Assuming workforce demand as a factor of uncertainty, a two-stage stochastic model is proposed.

To solve the proposed mixed-integer model in the real-world cases and large-scale problems, a Benders’ decomposition algorithm is introduced. Some test instances are solved, with scenarios generated by Monte Carlo method. For some test instances, to find the number of suitable scenarios, the authors use the sample average approximation method and to generate scenarios, the authors use Latin hypercube sampling method.

The results show a reasonable performance in terms of both quality and solution time. Finally, the paper concludes with some analysis of the results and suggestions for further research.

Researchers have attracted to other uncertainty factors such as costs and products demand in the literature, and have little attention to workforce demand as an uncertainty factor. Furthermore, most of the time, researchers assume that there is no difference between the education level and skill, while they are not necessarily equivalent. Hence, this paper enters these elements into decision making.