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Seeks to answer the question: have the reasons for using flex‐rigid circuit boards changed through the years?

The paper presents the development of flex‐rigid circuit board construction techniques from the first applications to the current status of a modern interconnection system. The paper discusses that it was the military and avionic industry that in the past required an interconnection technique that was reliable under environmental stress but compact and lightweight. Today it is the automotive and communication industry that is driving the development of printed circuit board technology.

Finds that wiring and interconnection must be cheap, reliable, light in weight, and must fit into very small housings. The demand for complex interconnection solutions like the flex‐rigid circuit technique is rising with the increased level of integration of more functions into electronic devices. The reasons for using flex‐rigid circuitries are nearly still the same as in the beginning.

Shows how the flex‐rigid circuit board technology has developed during the last 30 years.

Using a unique dataset of a commercial microfinance institution (MFI) in Madagascar, the purpose of this paper is to investigate how credit access probabilities and loan volume rationing magnitudes for farmers change if the MFI switches to offer flexible microfinance loans, which can account for agricultural production specifics.

The authors estimate probit models for the probability of receiving a loan and Heckman models to investigate the magnitude of volume rationing for all micro loan applications and disbursements of the MFI, differentiating between farmers with standard microfinance loans and farmers with flexible microfinance loans.

The results reveal that agricultural firms with flexible microfinance loans have significantly higher credit access probabilities than non‐agricultural firms and agricultural firms with standard microfinance loans. Furthermore, it was found that agricultural firms with flexible microfinance loans are stronger volume rationed than non‐agricultural firms and agricultural firms with standard microfinance loans.

Even if the authors can show that access to credit for agricultural firms in Madagascar can be enhanced by the provisioning of flexible microfinance loans, the investigated MFI only introduced flexible microfinance loans in 2011 and currently only offers them through five branch offices. Thus, the product is new to the MFI, and results might change with increasing outreach to other geographic regions in Madagascar. Furthermore, the conditions for agricultural production in Madagascar are unique, and the results might change in different country contexts.

The paper's findings suggest that flexible microfinance loans can contribute to the financial inclusion of farmers with seasonal production types. They also suggest that standard microfinance loans seem to be adequate for farmers with less seasonal production types, e.g. animal husbandry.

To the best of the authors' knowledge, this is the first paper to investigate the effects of flexible microfinance loan provision for credit access of small agricultural firms in developing countries in general, and in Madagascar in particular.

This paper aims to draw on the field of real estate management to explore the cost of flex-offices as well as the corporate discourse toward it and to identify the possible gap between real estate directors' discourse and the real cost of flex-offices.

This paper follows the grounded theory approach. Three studies were conducted: 16 semi-structured interviews with real estate actors, categorization of internal corporate documents and a thorough content analysis of the press discourse.

There is a positive vision as well as a very optimistic outlook on the flex-office on the part of real estate actors and the press. This research shows that reality does not reflect the discourse as 12 hidden costs identified are not currently factored into costs when setting up a flex-office, which can distort the discourse and efficiency. It will be interesting to measure those hidden costs in future research so as to have an objective discourse and a better cost estimate when deploying this kind of workspace.

Contradict the widespread discourse about flex-offices by highlighting the hidden costs that should be taken into consideration to allow managers to make accurate estimates. Although these hidden costs may seem ancillary at first sight, they might have an impact on efficiency.

In this article a proposal of a non‐traditional methodology in achieving optimal flexibility with minimal inventory risk will be applied. The non‐traditional methodology will be able to achieve different levels of the production schedule changes with maximum flexibility and minimal inventory risk. The basic principle, implementation methodology as well as its effectiveness and benefits will be discussed. In order to overcome the risk of achieving flexible manufacturing or enhancing supply chain management, this article will address issues on methods to accommodate production sequence changes which include total production quantity change in a short lead time. The study uses the Family Ordering System methodology which has proven capable in solving manufacturing flexibility issues by reducing the total manufacturing lead time. Family Ordering System provides the flexibility of model changes and reduces production line stoppage as a result of part shortage by carrying extra inventory of unique parts.

More companies embrace flexible work arrangements (FWA) as one of their employee retention strategies, yet its effectiveness is not consistent. Generally, past researchers use the social exchange theory to explain how FWA lowers turnover intention, while the rest adopts the border theory to justify why FWA can be ineffective. Here, the authors compare the competing theories for the first time to differentiate the theoretical reasoning of three forms of FWA (flex time, flex leave and homeworking). Two mediators (organisational commitment and work−family conflicts) are chosen to represent the mechanism of each theory.

The authors employ the latest wave of the International Social Survey Program (ISSP) Work Orientation Module from 2015. Based on nationally representative data from 35 nations and 17,604 participants, the authors employed simple mediation and parallel double-mediation models via bootstrapping procedures to investigate the theoretical reasoning behind each FWA.

The results indicate that organisational commitment and work−family conflicts as significant mediators in all models, supporting both theories. The authors first tested each mediator in separated models. In models concerning the social exchange theory, all FWA lead to increased organisational commitment before lowering turnover intention, implying the beneficial outcomes of FWA. However, findings also support the border theory's perspective where flex time and homeworking increase turnover intention through heightened work−family conflicts. The parallel double-mediation further suggests that all three FWA forms have their unique theoretical framework, impacting turnover intention differently.

Both the social exchange theory and border theory are well-developed theories but grounded on different theoretical reasoning. This is the first paper that compares both theoretical perspectives in the context of FWA. It offers a new perspective in explaining the inconclusive effectiveness of FWA and provides future researchers a more integrated interpretation and prediction of FWA's impact on turnover intention.

“A patterned arrangement of printed wiring utilizing flexible base material with or without flexible coverlayers”. The balance of this brief article will hopefully serve to help the reader understand this remarkable interconnection technology and appreciate just how widely the technology can be applied.

Flex‐rigid circuits have been used for many years, primarily by the military, as a method to reduce the size and increase the reliability of electronic systems. However, in today's emerging designs where high speed ASICs are often the dominant components, flex‐rigid circuit assemblies are now an attractive solution for providing high density transmission line interconnects from board to board. Much of today's circuitry is being committed to ASIC designs to increase both circuit density and speed. Following this path, designers are faced with the task of interconnecting high lead count SMT packages often with as many as 300 to 500 leads per device, each dissipating several watts. At these power densities conductive cooling through the circuit board is often a necessity, dictating the use of either metal cores or heat exchangers. To make efficient use of the core and minimise weight, designs generally require SMT packages to be mounted on both sides of the core with electrical communication from side to side. However, as more exotic core materials (carbon fibre matrix, beryllium, etc.) and liquid cooled heat exchangers are used, electrical communication through the core has become difficult, if not impossible, in some cases. Instead, high density flex‐rigid assemblies are used to partition the circuit, allowing the board to ‘fold’ over the core. This results in hundreds of signal lines that must cross the flex, obeying the electrical design rules dictated by the rigid sections to maintain impedance values and crosstalk margins. This paper focuses on recent work at AIT, producing high density flex‐rigid circuits using embedded discrete wiring technology to meet the above requirements. Using 0.0025 in. diameter polyimide insulated wire, as many as 100 lines per linear inch can pass over the flex region on a single layer. This generally results in a single flex layer where all wires can be referenced to a continuous ground plane from board to board. Controlled impedance is easily maintained due to the uniform wire geometry, and high frequency attenuation is significantly lower than on equivalent etch circuit designs due to the smooth surface finish on the wire. In addition, the high interconnection density offered by this technique reduces the overall thickness of the rigid sections, thereby minimising the thermal resistance to the core.

This article comprises Chapter 6 from the recently published book ‘An Engineer’s Guide to Flexible Circuit Technology by J. Fjelstad

This paper investigates how large UK corporate occupiers perceive the potential role of flexible office space in their office portfolios in a post-pandemic context.

The research methodology is qualitative and applied. For a longitudinal survey, convenience sampling was used to obtain co-operation from 11 corporate real estate managers with responsibility for managing large corporate real estate portfolios spread across a range of business sectors and countries. Semi-structured interviews were selected as the core research method to seek and to optimise the balance between discovery and generalisability.

Although the pandemic has led corporate occupiers to fundamentally re-appraise where and when different work tasks are performed, it is not yet clear whether this has major implications for the flex space sector. The flex space model, with its blending of various occupiers and activities, is perceived to be poorly aligned with an increasing emphasis on the office as a core corporate hub facilitating connection, collaboration, enculturation, learning and creativity. Since most flex space is concentrated in central locations, it is also not well positioned to benefit from any decentralisation of office functions. However, as the flex space sector evolves in response to structural shifts in employment and working practices and business change, its various products are likely to be a continuing requirement from corporate occupiers for short-term solutions to demand shocks, the need for rapid market entry, accommodation for short-term projects and access to desk space in multiple locations.

Understanding occupiers' drivers in their decision-making on selecting the method of occupation will assist investors in how they might adjust what they offer in the marketplace.

Whilst there has been a substantive number of surveys of corporate occupiers' perceptions and intentions regarding their office portfolio, this paper focusses on a specifically on the flex space sector. Whilst previous research has mainly been extensive, this research study is intensive.

With the fatigue ductility test the ductility of metallic foils and flexible metal foil/dielectric laminates can be determined. Ductility together with tensile strength allows prediction of the fatigue behaviour of flexible printed wiring (FPW) in both the low‐cycle/high‐strain (ductility dependent) and the high‐cycle/low‐strain (strength dependent) ranges. However, for laminates and FPW with Kapton as the dielectric the standard fatigue ductility test method does not produce the expected results and flex life predictions deviate from experimental results. The results of a study to determine the cause of this anomalous behaviour of Kapton FPW and to find correlative correction procedures are reported. Corrections to account for both the cyclic strain‐hardening of rolled annealed copper foil and the Kapton/adhesive/copper interactions for asymmetric single‐sided FPW are presented. With these corrections the ductility determination for copper foil laminated to a Kapton substrate using the fatigue ductility test produces good results, and the fatigue life of symmetric Kapton FPW can be predicted from the copper foil properties. The underlying mechanisms for the strong deviational flex behaviour of asymmetric single‐sided FPW could not be identified. The recommendation is made that for high‐cycle flex applications the FPW construction be precisely symmetrical. FPW made from copper‐clad Kapton with rolled annealed copper foil is the overwhelming choice and it is important that one has proper acceptance criteria at incoming inspection and that a valid prediction methodology for FPW flexural resistance and fatigue behaviour is available.