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The design, fabrication and experimental validation of defected microstrip structure (DMS) are proposed to address the problem of near-end crosstalk (NEXT) and far-end crosstalk (FEXT) between the microstrip transmission lines in a printed circuit board.

The proposed DMS evolved with the combination of spur line (L-shaped DMS) and U-shaped DMS topologies. This technique reduces the strength of electromagnetic coupling and suppresses crosstalk by optimizing the capacitive and inductive coupling ratio between the linked microstrip lines. The practical inductance value is much more significant in DMS than in defected ground structures (DGS), but the capacitance value remains the same.

A DMS unit is etched on the aggressor microstrip line instead of the DGS circuit. Because there is no leakage via the ground plane and the circuit size is far smaller than with DGS, the enclosure issue is disregarded. DMS structures have a larger effective inductance and are resistant to electromagnetic interference. A tightly coupled transmission line structure with minimal separation between the coupled microstrip line is designed using DMS. Further research must be conducted to improve the NEXT, FEXT and spacing between the transmission lines.

Simulation and actual measurement results show that the proposed DMS structure can effectively suppress crosstalk by analysing the S-parameters, namely, S_12, S_13 and S_14, with measured values of 1.48 dB, 20.65 dB and 21.099 dB, respectively. The data rate is measured to be 1.34 Gbps as per the eye diagram characterization. The results show that the NEXT and FEXT are reduced by approximately 20 dB in the frequency range of 1–11 GHz for mixed signals. The substantial measured results in the vector network analyser coincide with the computer simulation technology microwave studio suite simulation results.

The purpose of this paper is to design a suitable guard trace to reduce the electromagentic interference between two closely spaced high frequency transmission lines. A novel cross-shaped resonator combined via fence is passed down to alleviate far-end and near-end crosstalk (NEXT) in tightly coupled high-speed transmission lines. The distance between the adjacent transmission lines is increased stepwise as a function of trace width.

A rectangular-shaped resonator via fence is connected by a guard trace has been proposed to overcome the coupling between the traces that is separated by 2 W. Similarly, by creating a cross-shaped resonator via fence connected by guard trace that reduces the spacing further by 1.5 W.

A tightly coupled transmission line structure that needs separation by a designed unit cell structure. Further research needs to be conducted to improve the NEXT, far-end crosstalk (FEXT) and spacing between the transmission lines.

This study portrays a novel method that combines the resonators via fence with a minimum spacing between the tightly coupled transmission lines which reduce the NEXT and FEXT; thereby reducing the size of the routing area. The resultant test structures are characterized at high frequencies using time domain and frequency domain analysis. The following scattering parameters such as insertion loss, NEXT and FEXT of the proposed method are measured as 1.504 dB, >30 dB and >20 dB, respectively.

A prerequisite for automatic assembly by “factory‐intelligent” robots in the 1980s is the development of machine hand‐eye coordination systems. This paper presents a formal approach to choreographic robot vision systems to describe, command, and control a robot's complex manipulations via a set of basic sensory‐motor interactions. Hypothetical inference processes of choreographic vision are modeled by formalizing a plausible inference scheme of Polya and by introducing concepts of a context‐dependent relation theory. The resulting entailment/relational diagrams (eye‐hand data → choreographic properties → choreographic models) form a basis for choreographic robot vision.

This paper aims to analyze the negative impact of surface mount (SMT) pad and imperfect via structure such as stub, pad, non-functional pad (NFP) and anti-pad on the signal integrity at 40 Gbps transmission on printed circuit board (PCB) due to impedance mismatch or discontinuity. The optimized modeling of via and SMT structures is performed to achieve minimal impedance mismatch and insertion loss less than 10 dB for six-inch full path transmission line between transmitter and receiver on PCB at Nyquist frequency 20 GHz.

This work is split into two phases. The first phase involves optimization of via and SMT structures in three-dimensional electromagnetic (3DEM) simulation using Hyperlynx Via Wizard and Keysight EMPro software, respectively, followed by analysis of time domain reflectometry (TDR) and insertion loss (Sdd21). Whereas, in the second phase, full path hybrid mode simulation involving vias for signal layer transition, a 6-inch PCB channel and SMT pads is performed using Keysight ADS software to observe the TDR, Sdd21 and eye diagram at 40 Gbps transmission.

Imperfect via and SMT structures have a negative effect on signal reflection and attenuation. The optimized via and SMT minimizes the impedance mismatch by 81 per cent and insertion loss by 4.5 dB, ultimately enlarging the eye diagram opening to achieve minimal data loss at receiver with 40 Gbps transmission.

The results of original empirical research work on signal integrity analysis that optimizes the PCB channel design to achieve 40 Gbps signal transmission are presented in this study. It serves as a reference guide for high-speed PCB layout design.

To characterise the optical performance of organic multi‐mode optical waveguides integrated with printed circuit board (PCB) and to demonstrate the feasibility of 2.5 and 10 Gbps optical interconnection in board‐level, respectively.

This paper provides both qualitative and quantitative approaches for the characterization the wave guide performance, i.e. using loss measurement, optical beam profiling, ethernet verification, and eye‐diagram testing. In addition to wave guide loss measurement, the most significance part of the work reported in this paper is to evaluate optical wave guides with coupled VCSELs, by which a 3 dB coupling design budget can thus be identified. Furthermore, by artificially manipulating coupling conditions, practical concerns of EOPCB integration, including waveguide geometry, VCSEL driving power, alignment tolerance, coupling spacing, etc. are studied.

Thermal stability studies related to PCB lamination processes show the feasibility of organic waveguides integrated to traditional PCB manufacturing. For a direct VCSEL/PD coupling scheme, a 3 dB power budget is experimentally identified. For short reach optical interconnection, 10 Gbps up to 17 cm propagation on PCB can be achieved by using 50×50 μm multi‐mode organic waveguides, where a±25 μm tolerance of optical alignment is compatible to the design rules of PCB.

The value of the paper lies in its systematic approaches to identify the waveguide performance through both qualitative and quantitative indices. The correlation between geometry design, processes, coupling conditions, and optical performance of organic waveguides explored in detail. Not only is a standard eye‐diagram test used to verify the waveguide at 2.5 and 10 Gbps bandwidth, but also a prototype of optical data‐communication on giga‐ethernet is demonstrated for long term stability. Following these analytical methods, readers can understand more about the optical performance of waveguides when designing optical interconnection for high speed electro‐optical integrated PCBs.

This paper aims to analyze the impact of non-perfect reference plane on the integrity of microstrip differential signals at multi-gigabit transmission on a printed circuit board (PCB). The effects of non-perfect reference contributed by signal crossing over split plane such as impedance discontinuity and crosstalk are investigated by performing analysis in two phases.

The first phase involves three-dimensional electromagnetic modeling extraction using Keysight EMPro software. Meanwhile, the second phase involves the import of model extracted from EMPro into simulation using Keysight Advanced Design System that covers insertion loss, return loss, crosstalk, time domain reflectometry and eye diagram.

A non-perfect reference plane has a negative impact on signal reflection, attenuation and crosstalk. The analysis results are presented and discussed in detail in the later section of this paper.

The work that studied the impact of the width and the amount of gaps due to crossing of split planes being experienced on the signal integrity was performed by other researchers. Meanwhile, this paper focused on the impact of length and depth of the gap on signal integrity. These research papers serve as a reference guide for high-speed PCB layout design.

This paper describes a series of three evaluations of electronic textbooks on the Web, which focused on assessing how appearance and design can affect users’ sense of engagement and directness with the material. The EBONI Project's methodology for evaluating electronic textbooks is outlined and each experiment is described, together with an analysis of results. Finally, some recommendations for successful design are suggested, based on an analysis of all experimental data. These recommendations underline the main findings of the evaluations: that users want some features of paper books to be preserved in the electronic medium, while also preferring electronic text to be written in a scannable style.

The purpose of this paper is to present the problem of high‐speed data transmission on flexible printed circuits (FPC) and the common method for transmission signal designs on those FPCs. A new and novel approach using a “voided return path” of the coplanar transmission model is described and the ease of building them in mass production is described.

Microstrip transmission structures with a “mesh” return were studied and illustrated with emphasis on the problems encountered when the signal changes direction. A new solution using the “voided” return layer of the coplanar transmission model was proposed, simulated, built and tested.

The use of this novel coplanar structure to solve the problem of gigabit data transmission, with minimum noise and electromagnetic interference on flexible circuits can be achieved at low cost and with the flexibility to have multiple impedances and application for “Dynamic Flex”.

The “voided” coplanar structure has been used successfully. Further, developments are underway to employ a “modified” broadsided‐coupled differential structure that simulated a “twisted pair”.

The paper describes various high‐speed transmission structures on FPC used in computers and servers, combined with high volume mass‐production techniques. It presents the best cost scenario for optimal PCB design flexibility and applications.

The purpose of this paper is to describe the problems encountered and the solutions developed when using benchmarking and key performance indicators (KPIs) to monitor a major UK social house building innovation (change) programme. The innovation programme sought improvements to both the quality of the house product and the procurement process.

Benchmarking and KPIs were used to quantify performance and in‐depth case studies to identify underlying cause and effect relationships within the innovation programme.

The inherent competition between consortium members; the complexity of the relationship between the consortium and its strategic partner; the lack of an authoritative management control structure; and the rapidly changing nature of the UK social housing market all proved problematic to the development of a reliable and robust monitoring system. These problems were overcome by the development of multi‐dimensional benchmarking model that balanced the needs and aspirations of the individual organisations with the broader objectives of the consortium.

Whilst the research methodology provides insight into the factors that affected the performance of a major innovation programme its findings may not be representative of all projects.

The lessons learnt should assist those developing benchmarking models for multi‐client consortia.

The work reported in this paper describes an inclusive approach to benchmarking in which a multiple client group and their strategic partner sought to work together for shared gain. Very few papers have addressed this issue.

This paper seeks to report the findings of a research project that observed and monitored the performance of a four‐year strategic partnering agreement between a consortium of Registered Social Landlords (AMPHION) and their contracting partner as they procured approximately 800 new houses, across 33 separate development projects.

The research project used a combination of in‐depth case studies (of individual housing projects and the relationship between the client group and their main contractor) supplemented by quantitative measures of project performance (Key Performance Indicators) and integrated workshops to study the operational factors that affected the success of the partnering initiative.

The paper concludes that failures to manage expectations within and between partners undermined confidence and trust in the partnering process.

Whilst strategic partnering within the UK social housing sector was immature at the time of the study, the lessons learned have implications for other organisations considering strategic partnering relationships.

Evidence is provided from a long‐term study of strategic partnering which explores the dynamic nature of strategic partnering and its impact on success. Very few studies have addressed this issue.