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The purpose of this paper is to provide an overview of the research in a project aimed at developing manufacturing techniques for integrated optical and electronic interconnect printed circuit boards (OPCB) including the motivation for this research, the progress, the achievements and the interactions between the partners.

Several polymer waveguide fabrication methods were developed including direct laser write, laser ablation and inkjet printing. Polymer formulations were developed to suit the fabrication methods. Computer‐aided design (CAD) tools were developed and waveguide layout design rules were established. The CAD tools were used to lay out a complex backplane interconnect pattern to meet practical demanding specifications for use in a system demonstrator.

Novel polymer formulations for polyacrylate enable faster writing times for laser direct write fabrication. Control of the fabrication parameters enables inkjet printing of polysiloxane waveguides. Several different laser systems can be used to form waveguide structures by ablation. Establishment of waveguide layout design rules from experimental measurements and modelling enables successful first time layout of complex interconnection patterns.

The complexity and length of the waveguides in a complex backplane interconnect, beyond that achieved in this paper, is limited by the bend loss and by the propagation loss partially caused by waveguide sidewall roughness, so further research in these areas would be beneficial to give a wider range of applicability.

The paper gives an overview of advances in polymer formulation, fabrication methods and CAD tools, for manufacturing of complex hybrid‐integrated OPCBs.

The purpose of this paper is to present a novel manufacturing process that aims to pattern metal tracks onto polyimide at atmospheric pressure and ambient environment. The process can be scaled up for industrial applications.

From a thorough literature survey, different approaches were carried out for processing polyimide. Following a design of experiments for the processing and various characterisation techniques, a micro‐coil was manufactured as a test demonstrator.

The characteristics of some main formaldehyde‐based electroless copper baths were compared. The quality of the sidewalls was characterised and the performance of the process was assessed.

This paper demonstrates a high‐value manufacturing technique that is mass manufacturable, low cost and suitable for use on 3D surfaces. Criteria required for the development of a direct‐writing process have been described. The issues surrounding electroless plating on polyimide have been explained.

The purpose of this paper is to present the need, and a potential solution, for in‐plane routing of optical signals for optical‐enabled circuit boards.

Multimode waveguides and integrated 45° in‐plane mirror structures were made in a low loss acrylate‐based photopolymer using excimer laser ablation. The fabrication of multimode waveguides and mirrors was carried out in a single laser system which minimised alignment issues.

It was established that in‐plane mirror fabrication using laser ablation can be achieved and can potentially be used to define mirrors in waveguides made by other methods such as photolithography.

While the concept (integrated in‐plane mirror) was demonstrated, the viability of its deployment will depend on the results of optical loss measurements for which further research is required.

The paper gives an overview of the design concept and fabrication steps for an in‐plane embedded mirror.

The purpose of this paper is to present the latest results from research and development into future optical printed circuit board (OPCB) interconnects and low‐cost assembly methods.

A novel method of high‐precision passive alignment and assembly to OPCBs was invented and a full evaluation platform developed to demonstrate the viability of this technique.

The technique was successfully deployed to passively align and assemble a lens receptacle onto an embedded polymer waveguide array in an electro‐OPCB. The lens receptacle formed a critical part of a dual lens pluggable in‐plane connection interface between peripheral optical devices and an OPCB. A lateral in‐plane mechanical accuracy of ±2 μm has been measured using this technique.

As this is a free space optical coupling process, surface scattering at the exposed waveguide end facet was significant.

This paper details a novel method of passively assembling arbitrary optical devices onto multi‐mode optical waveguides and outlines the procedure and equipment required. A lens coupling solution is also presented which reduces susceptibility of a connecting optical interface to contamination.

To introduce the Innovative Electronics Manufacturing Research Centre Flagship Project: Integrated Optical and Electronic Interconnect PCB Manufacturing, its objectives, its consortium of three universities and ten companies and to describe the university research being carried out. This paper briefly reviews the motivation for developing novel polymer formulations, fabrication techniques, layout design rules and characterisation techniques for hybrid electronic and optical printed circuit boards (PCBs) using multimode polymer optical waveguide interconnects.

The authors are investigating a number of different fabrication techniques which they compare with each other and with modelled calculations of waveguide components. The fabrication techniques include photolithography, laser ablation, direct laser writing, embossing, extrusion and ink jet printing.

A number of design rules for polymer multimode waveguides have been found and published. Techniques for ink jetting polymer to print waveguides and laser ablation techniques have been developed. New formulations of polymer which cure faster for direct writing have also been developed.

Further work is needed to thicken the ink jet printed polymer and to investigate side wall roughness of the ablated waveguides and development of new polymer formulations for dry film. Further research is also needed on construction of prototype system demonstrators.

The fabrication techniques being developed are designed to be transferred to industrial PCB manufacturers to enable them to make higher value optical PCBs. The design rules being discovered are being entered into commercial PCB layout software to aid designers of optical PCBs.

The paper is of interest to PCB manufacturers who wish to upgrade their processes to be able to manufacture optical PCBs. The university research is original and some has been published as shown in the publications in the reference list.

The purpose of this paper is to study fabrication of optical‐PCBs on panel scale boards in a conventional modern PCB process environment. It evaluates impacts on board design and manufacturing with the developed optical board verifiers outlining challenges and requirements for manufacturing low‐loss waveguide structures and optical building blocks. The study aims to expand the current knowledge in the field by adding results obtained by utilizing industrial production infrastructure and developed scalable manufacturing processes to fabricate optical‐PCBs and board assemblies in high‐volumes and low‐cost manner.

Impacts on board design and manufacturing were studied with the developed optical technology verifiers. One verifier is optical‐PCB with embedded waveguides, integrated i/o couplers and optical vias. Another verifier is large size PCB with optical layer. A system‐level optical board assembly with 12.5 Gb/s Tx/Rx devices on surface mounted ball grid array (BGA) modules is designed for optical link analysis. Fabricated optical structures on verifiers are evaluated of their physical characteristics utilizing optical, SEM, LSCM analysis methods. Performance testing is conducted using standard optical transmission measurement methods and equipment.

The paper provides empirical results about fabrication of multimode optical waveguides with conventional PCB process equipment. Results suggest that current coating and imaging equipments are capable of producing optical waveguide patterns with high resolution and size accuracy. However, fabricators would require larger process window and defect tolerance for processing optical materials to obtain low‐loss waveguides with sufficient yields.

Because of the limited amount of design variants in production verifiers evaluated in this paper, some impacts like effect of base material, board construction, optical layer location and beam coupling solution were not evaluated. Likewise, impacts on long‐term stability and cost were not addressed. These factors however require further investigation to address technical feasibility of optical PCBs technology prior commercial high volume production.

The paper includes implications for the development of a fabrication methods and testing procedures for optical polymer waveguide layers on PCBs.

This paper fulfils need to provide results on design, fabrication and characterization of optical PCBs and backplanes from industrial fabricator's perspective. The paper provides input for end‐user and developers to evaluate technical performance, robustness, and maturity of building blocks and supply chain to support polymer waveguide based technology for intra‐system optical links.

The purpose of this paper is to investigate the reliability measures, namely, availability, reliability, mean time to failure and expected profit. The authors also analyse the sensitivity of these reliability measures.

Depending upon the real industrial relevance, a generalized system which is easily repairable, extremely reliable and of high quality is expected by the rapid growth of the digital economy. Considering reliability, as one of the performance measure, the authors have designed a complex system which consists of three subsystems, namely, A, B and C in series configuration. The subsystem A consists of n numbers of units which are arranged in parallel configuration, subsystem B consists of two sub-subsystems X and Y align parallel to one another, where X is a type of 1-out-of-n:F. Failure and repair rates are assumed to be follow the general distribution.

The system is deeply studied by the usage of the supplementary variable technique, Laplace transformation and Markov’s law. Various conclusive results such as availability and reliability of the system, mean time to failure, cost and sensitivity analysis have been discussed further.

Through the systematic view of reliability measures of the proposed system, performance of the system can be enhanced under high profit.

A multi-state linear k-within-(r, s)-of-(m, n): F lattice system consists of m×n components arranged in m rows and n columns. The possible states of the system and its components are: 0, 1, 2, …, H. According to k values, the system can be categorized into three special cases: decreasing, increasing and constant. The system reliability of decreasing and constant cases exists. The purpose of this paper is to evaluate the system reliability in increasing case with i.i.d components, where there is no any algorithm for evaluating the system reliability in this case.

The Boole-Bonferroni bounds were applied for evaluating the reliability of many systems. In this paper, the author reformulated the second-order Boole-Bonferroni bounds to be suitable for the evaluation of the multi-state system reliability. And the author applied these bounds for deriving the lower bound and upper bound of increasing multi-state linear k-within-(r, s)-of-(m, n): F lattice system.

An illustrated example of the proposed bounds and many numerical examples are given. The author tested these examples and concluded the cases that make the new bounds are sharper.

In this paper, the author considered an important and complex system, the multi-state linear k-within-(r, s)-of-(m, n): F lattice system; it is a model for many applications, for example, telecommunication, radar detection, oil pipeline, mobile communications, inspection procedures and series of microwave towers systems.

This paper suggests a method for the computation of the bounds of increasing multi-state linear k-within-(r,s)-of-(m,n): F lattice system. Furthermore, the author concluded that the cases that make these bounds are sharper.

The purpose of this paper is to deliberate the system reliability of a system in combination of three subsystems in a series configuration in which all three subsystems function under a k-out-of-n: G operational scheme. Based on computed results, it has been demonstrated that copula repair is better than general repair for system better performance. The supplementary variable approach with implications of copula distribution has been employed for assessing the system performance.

Probabilistic assessment of complex system consisting three subsystems, multi-failure threats and copula repair approach is used in this study. Abbas Jubrin Bin, V.V. Singh, D.K. Rawal, in this research paper, have analyzed a system consisting of three subsystems in a series configuration in which all three subsystems function under a k-out-of-n: G operational scheme. The supplementary variable approach with implications of copula distribution has been employed for assessing the system performance. Based on computed results, it has been demonstrated that copula repair is better than general repair for system better performance.

In this analysis, four different cases of availability are analysed for Gumbel–Hougaard family copula and also four cases for general repair with similar failure rates are studied. The authors found that when failure rates increase, the system availability decreases, and when the system follows copula repair distribution, the system availability is better than general repair.

This research may be implemented in various industrial systems where the subsystems are configured under k-out-of-n: G working policy. It is also advisable that copula repair is highly recommended for best performances from the system. On the basis of mean time to system failure (MTSF) computations, the failure rate which affects system failure more needs to be controlled by monitoring, servicing and replacing stratagem.

This research work has great implications in various industrial systems like power plant systems, nuclear power plant, electricity distributions system, etc. where the k-out-of-n-type of system operation scheme is validated for system operations with the multi-repair.

This work is a new work by authors. In the previously available technical analysis of the system, the researchers have analyzed the repairable system either supplementary variable approach, supplementary variable and system which have two subsystems in a series configuration. This research work analyzed a system with three subsystems with a multi-repair approach and supplementary variables.

During the COVID-19 pandemic in 2020–2021 in Indonesia, the indoor environmental quality (IEQ) of local houses occupied by infected occupants was adversely affected. This paper aims to appraise the IEQ of the affected Banda Aceh houses with insights into enabling them to be resilient against the negative impacts of the pandemic.

Quantitative field measurement in the case study of five concrete houses located in urban areas which are affected by IEQ factors: (1) indoor air quality (IAQ), (2) thermal comfort and (3) visual comfort, compared against the Indonesian National standard (SNI). The case study involved measurement of the first two factors over 24 h, while the third factor was measured during sun hours. Considering the limitations of the measuring tools for logging available data in this research, air quality is measured from 8 am to 10 pm.

Thermal comfort in the affected houses is generally regarded as warm, optimal and cool comfort, indicated by the effective temperatures of between 20.5 and 27.1°C. Frequently closed windows, limited land area and access had caused a lack of air circulation, with air velocity of dominantly 0 m/s in the houses. The illuminance of natural light received in three houses was insufficient – less than 120 lux as compared with the other two. This study found an uptrend of higher air temperature and relative humidity in the affected houses resulting in poorer IAQ; conversely, the higher the air velocity in the houses, the fewer the indoor air pollutants such as formaldehyde (HCHO), total volatile organic compounds (TVOC) and carbon dioxide (CO₂₎.

This study is a pioneer in evaluating IEQ in houses occupied by COVID-19 patients in Indonesia, especially in dwelling cases in Aceh Province. It also encompasses environmental and societal challenges to sustaining resilient buildings in pandemic hit regions.