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The flexible printed circuit board (FPCB) can be an alternative to the rigid printed circuit board because of its excellent flexibility, twistability, and light weight. Using FPCB to construct personal computer (PC) motherboard is still rare. Therefore, the present study aims to investigate the fluid‐structure interaction (FSI) behaviors of the newly proposed FPCB motherboard under fan‐flow condition in the PC casings.

The deflection and stress induced, which are usually ignored in the traditional rigid motherboard, are the main concern in the current FPCB motherboard studies. Only a few studies have been conducted on the effect of inlet locations, effect of inlet sizes, effect of multi‐inlets, and effect of a two‐fan system. These numerical analyses are performed using the fluid flow solver FLUENT and the structural solver ABAQUS; they are real‐time online coupled by Mesh‐based Parallel Code Coupling Interface (MpCCI).

A smaller inlet size can cause higher deflection and stress fluctuations, but the fluctuations can be reduced by incorporating the multi‐inlets design. In addition, the inlet locations and two‐fan system can prominently affect the magnitudes of the deflection and stress induced.

The current study provides better understanding and allows designers to be aware of the FSI phenomenon when dealing with the FPCB motherboard. Although the present study primarily focuses on the motherboard, the findings could also contribute valuable information for other FPCB applications.

The present study extends the FSI investigation from the previous novel approach of FPCB motherboard, and uniquely explores the behaviors of the FPCB motherboard inside different PC casings.

Casing damage problems are increasingly prominent in oil fields, most of which were caused by casing external squeezing loads. The traditional calculation method of casing external squeezing loads is not very accurate now, especially in complex formation. The purpose of this paper is to propose a new calculation method to solve the problem of actual casing loads under above conditions.

Based on Lame’s model of elastic mechanics, a new calculation method of casing external squeezing loads is deduced. Comprehensive influence laws of the loads which caused by in-situ stress, internal pressure, formation parameters, cement annulus parameters and casing parameters are analyzed.

The paper provides a new calculation method of casing external squeezing loads, by which the dispersion effect of internal liquid pressure caused by casing wall material is eliminated. The main influence factors of casing external squeezing loads are in-situ stress and formation elastic modulus.

The model and boundary conditions used in the paper is based on elastic mechanics. The accuracy of the calculation results depends on the quality and accuracy of the input formation parameters.

This paper proposes a new method to calculate casing external squeezing loads. And compared with traditional methods, this method is more practical.

The study applies a multimodal approach to position aesthetic innovation, i.e., the strategic use of aesthetic design attributes, such as color and shape, as an institutionalized aspect of competition, rather than as a firm-specific differentiation strategy, in settings that favor the symbolic meanings of products. Empirically, the study offers a detailed case study of the personal computer (PC) industry to examine the institutionalization of aesthetic innovation as a dimension of competition across industrial firms. The study examines the color and shape of PCs over the 1992–2003 period and situates changes to these attributes in the competitive conditions that characterized the industry, paying particular attention to the introduction of the Apple iMac in 1998. Furthermore, it examines the discursive manifestations of aesthetic innovation by content analysis of reviews of PCs and interviews with industry executives. Findings demonstrate that, in a period coinciding with a decline in demand for PCs and an overall mature market as well as with the introduction of the iMac, the majority of firms engaged in aesthetic innovation and used a greater number of aesthetic words in describing their PCs.

Differing from previous studies trying to solve the electromagnetic compatibility (EMC) issue by addressing single factor, this study aims to combine measures of shielding, filtering and grounding to design parameters with the Taguchi method at the beginning of product design to come up with the optimal parameter combination.

EMC-related performance such as radiated emission, conduction interference and electrical fast transient/burst immunity (EFT) are response variables, whereas the printed circuit board and mechanic design-relevant parameters are considered as control factors. The noise factors are peripherals used together with the tablet.

The optimal design parameter matrix based on results from the application and integration of multivariate analysis method of principal component grey relation and technique for order preference by similarity to ideal solution suggests 14 grounding screw holes, cooling aperture of casing at diameter of 3 mm and staggered layout and 300O filter located at source of noise. Validation of this matrix shows around 10, 1 and 8 per cent improvement in radiation, conduction interference and EFT immunity.

The multivariate quality parameters’ design method proposed by this study improves EMC characteristics of products and meets the design specification required by customer, accelerating electronic product research and development process and complying with electromagnetic interference test regulations set forth by individual country.

This study aims to investigate the interaction of independent variables [Reynolds number (Re), thermal power and the number of ball grid array (BGA) packages] and the relation of the variables with the responses [Nusselt number ((Nu) ¯ ), deflection/FPCB’s length (d/L) and von Mises stress]. The airflow and thermal effects were considered for optimizing the Re of various numbers of BGA packages with thermal power attached on flexible printed circuit board (FPCB) for optimum cooling performance with least deflection and stress by using the response surface method (RSM).

Flow and thermal effects on FPCB with heat source generated in the BGA packages have been examined in the simulation. The interactive relationship between factors (i.e. Re, thermal power and number of BGA packages) and responses (i.e. deflection over FPCB length ratio, stress and average Nusselt number) were analysed using analysis of variance. RSM was used to optimize the Re for the different number of BGA packages attached to the FPCB.

It is important to understand the behaviour of FPCB when exposed to both flow and thermal effects simultaneously under the operating conditions. Maximum d/L and von Misses stress were significantly affected by all parametric factors whilst (Nu)¯ is significantly affected by Re and thermal power. Optimized Re for 1–3 BGA packages with maximum thermal power applied has been identified as 21,364, 23,858 and 29,367, respectively.

This analysis offers a better interpretation of the parameter control in FPCB with optimized Re for the use of force convection electronic cooling. Optimal Re could be used as a reference in the thermal management aspect in designing the BGA package.

This research presents the parameters’ effects on the reliability and heat transfer in FPCB design. It also presents a method to optimize Re for the different number of BGA packages attached to increase the reliability in FPCB’s design.

The production of steel pipes with guaranteed external collapse pressure (e.g. high collapse casings for oil wells) requires the implementation of an accurate process control. To develop that process control it is necessary to investigate how different parameters affect the external collapse pressure of the pipes. Experimental/numerical techniques implemented to investigate the collapse behavior of steel pipes are presented. The discussion of the experimental techniques includes the description of the facilities for performing external pressure collapse tests and the description of an imperfections measuring system. The numerical techniques include 2D and 3D finite element models. The effects on the value of the pipes’ external collapse pressure of their shape, residual stresses and material properties are discussed.

Due to the economic benefits and environmental awareness, most of the battery manufacturing industries in India are interested to redesign their existing supply chain network or to incorporate the effective closed loop supply chain network (CLSCN). The purpose of this paper is to develop CLSCN model with eco-friendly distribution network and also enhance recycling to utilize recycled lead for new battery production. The existing CLSCN model of a battery manufacturing industry considered for case study is customized for attaining economic benefit and environmental safety. Hence, single objective, multi-echelon, multi-period and multi-product CLSCN model with centralized depots (CD) is developed in this work to maximize the profit and reduce the emission of CO₂ in transportation.

The proposed CD has the facility to store new batteries (NB), scrap batteries (SB) and lead ingot. The objective of the proposed research work is to identify potential location of CD using K-means clustering algorithm, to allocate facilities with CD using multi-facility allocation (MFA) algorithm and to minimize overall travel distance by allowing bidirectional flow of materials and products between facilities. The proposed eco-friendly CLSCN-CD model is solved using GAMS 23.5 for optimal solutions.

The performance of the proposed model is validated by comparing with existing model. The evaluation reveals that the proposed model is better than the existing model. The sensitivity analysis is demonstrated with different rate of return of SB, different proportion of recycled lead and different type of vehicles, which will help the management to take appropriate decision in the context of cost savings.

This research work has proposed single objective, multi echelon, multi period and multi product CLSCN-CD model in the battery manufacturing industry to maximize the profit and reduce the CO₂ emission in transportation, by enhancing the bidirectional flow of materials/products between facilities of entire model.

A Hughes 369 HS helicopter was making a planned flight from Graunt Courts, Raynes, Essex, to Battersea Heliport. The helicopter lifted off at about 0955 hous and the initial climb trajectory appeared slightly shallower than normal, but nothing else unusual was reported. At about 0955:40 hrs, the helicopter called Stansted Approach and was told to standby. At 0955:42.4 hrs a primary radar return on Debden Radar was recorded, about ½nm to the south‐west of Graunt Courts; the first SSR contact was at 0955:48.6 hrs but, as Mode C had not been selected on the helicopter's equipment, no altitude information was available. Analysis of radar contacts recorded between this time and 0956:13.3 hrs indicated a track of about 230° (M) and a ground speed of approximately 90kt.

Develops an original 12‐step management of technology protocol and applies it to 51 applications which range from Du Pont’s failure in Nylon to the Single Online Trade Exchange for Auto Parts procurement by GM, Ford, Daimler‐Chrysler and Renault‐Nissan. Provides many case studies with regards to the adoption of technology and describes seven chief technology officer characteristics. Discusses common errors when companies invest in technology and considers the probabilities of success. Provides 175 questions and answers to reinforce the concepts introduced. States that this substantial journal is aimed primarily at the present and potential chief technology officer to assist their survival and success in national and international markets.