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Wireless networks of sensors, displays and smart devices that can be placed on a person’s body could have applications in health monitoring, medical interventions and human–machine interfaces. Such wireless body networks are, however, typically energy-inefficient and vulnerable to eavesdropping because they rely on radio-wave communications. Here, we report energy-efficient and secure wireless body sensor networks that are interconnected through radio surface plasmons propagating on metamaterial textiles. The approach uses clothing made from conductive fabrics that can support surface-plasmon-like modes at radio communication frequencies. Our body sensor networks enhance transmission efficiencies by three orders of magnitude compared to conventional radiative networks without the metamaterial textile, and confine wireless communication to within 10 cm of the body. We also show that the approach can offer wireless power transfer that is robust to motion and textile-based wireless touch sensing. Energy-efficient and secure wireless body sensor networks can be created by using conductive fabrics that support surface-plasmon-like modes at radio communication frequencies.

Bioelectronic microdevices are an emerging class of biomedical devices miniaturized at the scale of a millimeter or less, which promise new capabilities for monitoring and treating human disease. Although rapid progress has been made in the sensing and actuation capabilities of microdevices, a major technological challenge remains in the way that these devices are powered within the body. In this review, we revisit the power requirements of microdevices, describe current methods for storing, transferring or harvesting energy in microdevices, provide an overview of emerging powering approaches and discuss the promise of microdevices in biomedicine.

The evaluation of bonding mechanisms between magnetron sputtered copper (Cu) thin films and a ceramic substrate was carried out using polycrystalline and monocrystalline alumina (Al 2 O 3 ) substrates with different surface roughness. Three different bonding mechanisms, viz., surface adsorption, mechanical interlocking, and diffusion bonding have been assessed. A tensile test was applied to measure the interfacial adhesion strength between the Cu films and the Al 2 O 3 substrate. The contribution to the interfacial adhesion from each of the bonding mechanisms was elucidated based on the adhesion strength. Without special surface pre-treatment, physical adsorption is the main factor for the film adhesion, contributing ~ 5.9 MPa adhesion strength between this directly sputtered Cu film and a flat Al 2 O 3 substrate. For substrates with surface roughness around 350–500 nm, mechanical interlocking enhances the film adhesion up to 18.6% compared to the flat surface. Post-deposition annealing at 300 °C has increased adhesion strength by 18%, and diffusion bonding may be operative.

This case traces the rags-to-riches entrepreneurial journey of Mr Pang Lim in building his Koufu food court business empire over the past decades amidst the changing landscape of the food and beverages industry in Singapore. After dropping out of school at 13 years old, Mr Pang started work as a dishwasher in the 1960s. However, his entrepreneurial acumen enabled him to seize strategic opportunities and adapt to changing environmental forces to become the owner of Koufu, a leading food court chain in Singapore. When Koufu was founded in 2002, the food court business in Singapore was already dominated by other major players such as Food Junction and Kopitiam. Yet, through astute management, clearly defined market segmentation strategies, and a significant focus in brand-building, Koufu grew into an international food court empire. By 2012, it consisted of 54 food courts in Singapore, one food court in Macau, and annual revenue of $152.7 million. Koufu also grew to become one of Singapore’s most established F&B brands with many sub-brands in its stable. This case is suitable for use in Marketing Strategy and Strategic Marketing courses. Key marketing and branding theories and concepts illustrated in this case include macro-environment and micro-environment analysis; segmentation, targeting and positioning strategies; and branding architectures (i.e., house of brands, branded house, house brand).

Implanted medical devices often transmit wireless signals to communicate with external equipment, but the efficiency of signal transmission is limited by internal reflection at the surface of the body. This work presents an approach to greatly enhance transmission, through the design of diffractive patterns capable of converting evanescent waves on the body's surface into waves propagating into the surrounding space. When printed on clothing and worn on the body, these patterns can increase the wireless signal's strength by nearly an order of magnitude, which may pave the way for longer-lasting and more functional bioelectronics.

In this study, nickel-doped diamond-like carbon (Ni-DLC) thin films were deposited on silicon (Si) substrates using a magnetron cosputtering system by varying DC power density applied to a Ni target at a fixed DC power density applied to a carbon (C) target. Their tribological properties were systematically investigated using a ball-on-disc microtribometer. The tribological results showed that increasing the DC power density applied to the Ni target more than 0.49 W/cm2 significantly increased the friction and wear of the Ni-DLC films due to the degraded sp3-bonded cross-linking structures of the films. However, the much lower friction and wear of the Ni-DLC-coated Si samples than those of the uncoated Si sample implied that the Ni-DLC films could effectively prevent their Si substrates from wear. It could be concluded that the Ni-DLC films could be used as high wear-resistant coatings for micromold applications because their tribological properties were significantly influenced by the DC power de...

High performance reduced graphene oxide (RGO)-Nafion (N) thin film electrodes coated on silicon (Si) substrates (RGO-N/Si) were successfully developed through thermal reduction of GO-N without delamination from the substrates. The restoration of the RGO-N nanostructure upon the addition of Nafion was proven by Raman spectroscopy (RS) and field emission scanning electron microscopy, and the restoration mechanism of the RGO-N nanostructure was proposed. Through the investigation using x-ray photoelectron spectroscopy (XPS), the polyfluorocarbon from Nafion possessed a function that could prevent the delamination of the RGO sheets from the substrates during the thermal reduction. The RGO-N/Si samples were later used for the determination of trace heavy metals, such as divalent lead, cadmium and copper ions (Pb2+, Cd2+ and Cu2+, respectively) using square wave anodic stripping voltammetry in a 0.1 M acetate buffer solution (pH 5). Based on the electroanalytical measurements, the RGO-N/Si samples exhibited a highly linear behavior in the detection of Cd2+, Pb2+ and Cu2+ over the concentration range of 50 nM to 300 nM with detection limits at nM levels. In addition, the RGO-N/Si samples presented good recoveries of target metals in tap water samples.

Stretchable optoelectronic materials are essential for applications in wearable electronics, human-machine interfaces and soft robots. However, intrinsically stretchable optoelectronic devices such as light-emitting capacitors usually require high driving alternating voltages and excitation frequencies to achieve sufficient luminance in ambient lighting conditions. Here, we present a healable, low-field illuminating optoelectronic stretchable (HELIOS) device by introducing a transparent, high permittivity polymeric dielectric material. The HELIOS device turns on at an alternating voltage of 23 V and a frequency below 1 kHz, safe operating conditions for human-machine interactions. We achieved a brightness of 1,460 cd m

A number of surface pre-treatments have been studied for their effectiveness on the adhesion strength between magnetron sputtered copper (Cu) thin film and polycrystalline alumina (Al2O3) substrate. The treatments include organic solvent cleaning, acid washing, heat treatment, plasma cleaning, and they were organized into different sequences in order to evaluate their individual contribution to the film adhesion. Adhesion strength was measured mechanically using a pull test. By proper pre-treatment, the adhesive strength of at least 34 MPa can be achieved with direct sputtering of Cu thin film onto the Al2O3 substrate. With the help of XPS, SEM, XRD, TGA and contact angle measurement, the effect of the different substrate surface treatment techniques has been elucidated.

Reduced graphene oxide (RGO) decorated with tin nanoparticles (SnNPs) was electrodeposited on glassy carbon sheet (GCS), i.e. G-Sn/GCS, with a drop-casting method followed by constant potential electroreduction. Raman spectroscopic analysis on the graphitic structure of the G-Sn/GCS confirmed a good intercalation of SnNPs in the RGO matrix. Field emission scanning electron microscopic measurements illustrated a uniform distribution of the SnNPs on the RGO sheets. The G-Sn/GCS showed a better electroanalytical performance than the bare GCS and RGO/GCS in the simultaneous determination of divalent cadmium ions (Cd 2+ ), lead ions (Pb 2+ ) and copper ions (Cu 2+ ) using square wave anodic stripping voltammetry. The electroanalytical measurements using the G-Sn/GCS were optimized at −1 V for 150 s in a 0.1 M acetate buffer solution (pH 5). The G-Sn/GCS demonstrated a highly linear behavior in the detection of Cd 2+ , Pb 2+ and Cu 2+ in the concentration range of 10 nM to 100 nM with detection limits of 0.63 nM, 0.60 nM and 0.52 nM (S/N=3), respectively. A mechanism for the formation of the G-Sn nanocomposite was proposed in this paper.

Reduced graphene oxide (RGO) decorated with gold nanoparticles (AuNPs) was electrodeposited on glassy carbon electrode (GCE) using cyclic voltammetric method. The results of Raman spectroscopy confirmed the simultaneous formation of AuNPs and reduction of graphene oxide through the electrodeposition process. Scanning electron microscopic measurements showed a uniform distribution of the AuNPs on the RGO sheets. The RGO-AuNP nanocomposite coated GCE (G–Au/GCE) was used to detect lead ions (Pb 2+ ) contained in a 0.1 M acetate buffer solution (pH 5.3) using square wave anodic stripping voltammetry (SWASV). The G–Au/GCE demonstrated higher detection sensitivity and stronger SWASV signals than the bare GCE, with the limit of detection of about 0.8 nM.

Graphene thin films were synthesized using a solid-state carbon diffusion method by thermally treating (heating at 1000 °C for 3 min and then cooling) nickel–carbon (Ni–C) mixed layers co-sputtered on silicon (Si) substrates with or without a silicon dioxide layer. Field-emission scanning electron microscopy, high resolution transmission electron microscopy and Raman spectroscopy were used to characterize the structure and composition of both the as-deposited and thermally treated Ni–C coated samples with respect to the C concentration of the Ni–C thin films. The graphene thin films were used as working electrodes in the simultaneous detection of trace heavy metal ions (Pb 2 + , Cd 2 + and Cu 2 + ) in acetate buffer solutions modified with bismuth ions (Bi 3 + ). The enhancing effect of Bi 3 + on the electroanalytical performance of the graphene electrodes was studied.

In this paper, the use of data mining and text mining techniques in business analytics and how they support the use of business intelligence in e-businesses are discussed. The distinction between data mining, business analytics and business intelligence is presented. Suggestions on how electronic businesses can leverage on data mining to enhance their competitiveness are discussed.

We demonstrate control of wireless power transfer to an implanted bioelectronic device using harmonic feedback from the backscattered field. The feedback mechanism relies only on inherent nonlinearities in the receiver circuit and can provide a direct measurement of the extracted power without any modification of the device. We use the method to control an implanted light-emitting diode while varying the coupling between the source and receiver.We demonstrate control of wireless power transfer to an implanted bioelectronic device using harmonic feedback from the backscattered field. The feedback mechanism relies only on inherent nonlinearities in the receiver circuit and can provide a direct measurement of the extracted power without any modification of the device. We use the method to control an implanted light-emitting diode while varying the coupling between the source and receiver.

Water is essential to keep us to survive, but improper and careless treatment of the wastewater from industrialization may cause the release of heavy metals, such as Lead (Pb), Cadmium (Cd) and Copper (Cu) to water supply. These heavy metals may disrupt the supply chains and human health if the food and water were overdosed with heavy metals. Hence, detection of trace heavy metals in water is important for human health. The electroanalysis method was used with newly developed graphene-based working electrodes for the detection of trace heavy metals in aqueous solutions in this research due to their inexpensiveness, portability and sensitivity. In this project, two methods were used in the fabrication of the graphene-based electrodes. The first was an electrochemical method, with which drop-cast graphene oxide (GO) was electrochemically reduced to reduced graphene oxide (RGO). The electrochemical method was selected because it is simple and economic. In order to enhance the sensitivity of the electrodes, the electrochemically reduced RGO (ERGO) electrodes were decorated with tin nanoparticles (SnNPs). The second method was thermal reduction, where the drop-cast GO was thermally reduced to RGO at a high temperature. The thermal reduction method was chosen because it could potentially achieve large scale production. In addition, the thermally reduced RGO was further decorated with platinum (Pt) NPs to improve its sensitivity and selectivity towards the analytes (Cd2+, Pb2+ and Cu2+) in electroanalysis. In the characterization of the fabricated electrodes, several instruments, such as x-ray photoelectron spectroscopy (XPS), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM) and energy dispersive x-ray spectroscopy (EDS) were been used. XPS was employed to investigate the reduction percentage of RGO by studying the carbon to oxygen (C/O) ratio. Raman spectroscopy was used to determine the graphitic structure of RGO by studying the D/G intensity ratio (ID/IG). FE-SEM was used to study the surface microstructure of the RGO based electrodes, while EDS was used to verify the elemental composition of metal NPs decorated RGO. In order to study the electrochemical behaviour of the electrodes, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were performed. The surface reversibility of the RGO based electrodes could be identified through CV, while the electron-transfer resistance (Ret) at the interface between electrodes and electrolytes could be determined through EIS. After that, several parameters, such as pH of buffer solution, pre-concentration potential and pre-concentration time, were systematically investigated to optimize the working conditions of the RGO-based electrodes during electroanalysis. Furthermore, the reproducibility, repeatability and storage stability of the prepared electrodes were also analyzed. After that, square wave anodic stripping voltammetry (SWASV) was performed to detect the analytes in aqueous solutions. Calibrations of the RGO-based electrodes were carried out to investigate the performance of the electrodes in electroanalysis, in terms of sensitivity, stability and selectivity. In addition, the limit of detection (LOD) of the analytes obtained from the electrodes was determined. Finally, real sample application was performed to justify the feasibility of the prepared RGO-based electrodes. Doctor of Philosophy (IGS)

Purpose – This paper seeks to look at healthcare service quality from the viewpoint of its negative impact on the industry when there is a deficiency in the delivery of service quality. To measure this impact, the potential loss of customers due to poor quality service is measured. A potential customer loss model is proposed. To address the competitive and financially driven healthcare delivery business, a three‐pillar approach, termed the Excellent Healthcare Service Model (EHSM), is introduced. This approach advocates that the healthcare industry should use a system view to deliver quality healthcare by taking into account quality, cost, and efficiency factors in a holistic manner. Design/methodology/approach – In this paper a survey questionnaire was used to gather data necessary to compute impact of deficient healthcare service. The questionnaire was administered to a sample of 400 people and the survey method used was intercept interview. Customer loss and potential customer loss due to deficient service were computed. Findings – In this paper, findings from the research indicated that, in the healthcare industry, for every 100 customers that experienced deficient service, about 70 customers would be unlikely to patronize the same organization again. In addition, for the same 100 customers who have experienced deficient service, about 75 of them will go on to tell on average nine family members and friends about their experiences. Through word of mouth from these 75 dissatisfied customers, there will eventually be about 465 persons who might have been potential customers but will probably not patronize the organization at all based on what the dissatisfied customers have told them. Practical implications – The ideas presented in this paper provide a new way of looking at service quality performance, through the impact of deficient service. With this knowledge, economic impacts of poor service quality could easily be quantified, and such economic‐based results are usually a better motivator for managers and workers to deploy quality improvement initiatives. Originality/value – The results and ideas presented in this paper are valuable for the healthcare industry. It provides an alternative approach to quantify service quality performance. The paper also proposes a system‐based approach to enhance service process performance.

Most organizations recognize that total quality management (TQM) is important but many do not know where to begin or how to sustain it in the long run. There are many examples of organizations that have successfully implemented quality management but there are also as many organizations that have failed in their implementations and perhaps many more that hesitate to embark on the quality journey. In fact, the growth and adoption of TQM in companies have to be facilitated increasingly by national governments. National governments are increasingly playing an active role in promoting and encouraging organizations to embrace TQM practices. Many countries have established national quality awards or business excellence awards to recognize deserving companies. Presents an excellence model for implementing and sustaining business excellence through a structured approach in implementing some of the best practices in TQM found in national quality award winners. Hopes that such a model would guide aspiring organizations in their quality journey. Develops the model using a case study approach on four past winners of the Singapore Quality Award.

This paper proposes a development methodology that uses the assessment criteria of the national quality award as the basis for creating a self‐assessment tool to measure quality performance in organizations. The Singapore Quality Award (SQA) assessment criteria were used as the framework for developing the self‐assessment tool. The SQA award criteria were translated into a multi‐item questionnaire. The self‐assessment tool is used to assess quality performance in various functions of the organization. The scores obtained using the assessment tool was tested against those of the recent SQA applicants. Results showed significant correlation between the assessment score bands and the actual score bands that they received on their SQA application. As of the end of 1998, about 200 business organizations in Singapore had used the self‐assessment tool. Self‐assessment tools using different national quality award criteria could also be developed based on the proposed development methodology described in this paper.

This paper presents first hand experience with the development and implementation of interactive multimedia instructional materials for an engineering economy course attended by 1000 engineering students over three years at Virginia Tech. The interactive software was developed from a National Science Foundation grant aimed at enhancing the undergraduate engineering curriculum through increased emphasis on design and economic principles. The purpose of this paper is to describe the type of multimedia instructional materials that were developed, how they were implemented, and, finally, to present an evaluation of the results from a survey in which the benefits of multimedia-based support materials were assessed.

This paper describes the use of multimedia lectures in an engineering economy course that is attended by 200 sophomore engineering students at Virginia Tech. The purpose of this paper is to examine the important issue of applying innovative information technology to support the effective dissemination of learning materials and to report on an experiment in which the benefits of multimedia-based support materials are assessed. Our hypothesis is that students exposed to a series of multimedia-based lectures will exhibit greater interest in the subject matter and will eventually perform better or as well as students in the traditional teaching environment. In addition, we hope to establish that students tend to become more involved (participate actively) in a multimedia-based teaching environment to the extent of actually making positive suggestions for improvement to the computer presentations. Just as important, we will support and encourage such contributions made by cross-disciplinary groups of students in the hope of cultivating student's interest in the subject matter throughout the course.

One of the major risks encountered in economic evaluation of foreign direct investment is the changes in future exchange rates that may affect the accuracy of the estimated economic worm of the investment. The objective of this article is to present a model for reducing the uncertainty associated with changes in foreign exchange rates when conducting economic evaluations of foreign direct investments. The model uses the Purchasing Power Parity Theorem and weighted averages for creating a procedural approach in which future changes in exchange rates are considered and included in the calculation of an overall profitability measure.

This paper provides a comprehensive list of relevant books and articles pertaining to the subject area of “engineering design,” with specific focus on the methodology, education, economics, and management aspects of the design discipline. The purpose of this survey of engineering design literature is to provide a compendium of books and articles that may be instrumental in facilitating the process of sharing and disseminating design knowledge