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The ability to appreciate the sensation of force and torque that is experienced by the slave device in a teleoperator system is essential for achieving remote manipulations such as assembly and disassembly, telesurgery, and remote handling of delicate and dangerous substances. This paper describes an intelligent teleoperator system that not only provides high quality force feedback information in teleoperation but also additional information about the contact formation between the slave device and the environment is presented to the operator. This paper also discusses the design of the teleoperator system and introduces its architecture. Experimental study using the developed teleoperator system is presented that highlights its performance in real life applications.

This paper aims to propose a novel integrated control method (ICM) for high-power-density non-inverting interleaved buck-boost DC-DC converter. To achieve high power conversion by conventional single phase DC-DC converter, inductor value must be increased. This converter is not suitable for industrial and high-power applications as large inductor value will increase the inductor current ripple. Thus, two-phase non-inverting interleaved buck-boost DC-DC converter is proposed.

The proposed ICM approach is based on the theory of integrated dynamic modeling of continuous conduction mode (CCM), discontinuous conduction mode and synchronizing parallel operation mode. In addition, it involves the output voltage controller with inner current loop (inductor current controller) to make a fair balancing between two stages. To ensure fast transient performance, proposed digital ICM is implemented based on a TMS320F28335 digital signal microprocessor.

The results verify the effectiveness of the proposed ICM algorithm to achieve high voltage regulating (under 0.01 per cent), very low inductor current ripple (for boost is 1.96 per cent, for buck is 1.1) and fair input current balance between two stages (unbalancing current less than 0.5A).

The proposed new ICM design procedure is developed satisfactorily to ensure fast transient response even under high load variation and the solving R right-half-plane HP zeros of the CCM. In addition, the proposed method can equally divide the input current of stages and stable different parallel operation modes with large input voltage variations.

Emerging event-driven applications such as the internet-of-things requires an ultra-low power operation to prolong battery life. Shutting down non-functional block during standby mode is an efficient way to save power. However, it results in a loss of system state, and a considerable amount of energy is required to restore the system state. Conventional state retentive flip-flops have an “Always ON” circuitry, which results in large leakage power consumption, especially during long standby periods. Therefore, this paper aims to explore the emerging non-volatile memory element spin transfer torque-magnetic tunnel junction (STT-MTJ) as one the prospective candidate to obtain a low-power solution to state retention.

The conventional D flip-flop is modified by using STT-MTJ to incorporate non-volatility in slave latch. Two novel designs are proposed in this paper, which can store the data of a flip-flip into the MTJs before power off and restores after power on to resume the operation from pre-standby state.

A comparison of the proposed design with the conventional state retentive flip-flop shows 100 per cent reduction in leakage power during standby mode with 66-69 per cent active power and 55-64 per cent delay overhead. Also, a comparison with existing MTJ-based non-volatile flip-flop shows a reduction in energy consumption and area overhead. Furthermore, use of a fully depleted-silicon on insulator and fin field-effect transistor substituting a complementary metal oxide semiconductor results in 70-80 per cent reduction in the total power consumption.

Two novel state-retentive D flip-flops using STT-MTJ are proposed in this paper, which aims to obtain zero leakage power during standby mode.

The purpose of this paper is to provide a decision-making tool achieving robust supply flow by incorporating strategic stock and contingent sourcing in mitigating minor and major disruptions.

The authors consider a firm with two suppliers where the main supplier is cost-effective but prone to disruptions and the back-up supplier is reliable but expensive due to built-in volume flexibility. In order to incorporate the randomness associated with disruptions and the available capacity during response time in the decision-making stage, the authors present a multi-stage robust optimization (RO) model. The design problem is to determine optimal strategic stock level and response speed of volume-flexible back-up supplier in order to achieve a robust supply flow.

The results show that the quality of optimal solution is improved by considering the randomness associated with available capacity. In addition, incorporating congestion effects allows identifying the appropriate level of supply chain responsiveness, thus improving the overall performance.

The novelty of the proposed model is the consideration of both strategic stock and volume flexibility in maintaining a robust supply performance while incorporating response capability and congestion effects.

Supply chain risk (SCR) has increasingly attracted academic and corporate interest; however, the SCR debate in academic literature is rather limited to case- and location-specific studies. Hence, the purpose of this paper is to utilize a systematic literature review (SLR) to explore the SCR research trends and gaps within the management literature.

To achieve the research objective an SLR, looking into 25 years since 1990, into supply chain risk management (SCRM) was conducted, which resulted in 114 papers.

While the SCRM literature is growing, results from the SLR identified limited organized understanding of what constitutes a holistic SCR process, and high reliance of particular categories for SCR, such as the high reliance on specific country settings (the USA and the UK); limited presence of cross competitive SCR process analysis and challenges in developing conceptual SCR frameworks.

The SCR embeds categories of location, scope of supply chain, risk management tools, and the industry sectors involved. The search for related publications was mainly used from a wide range of coverage from accountancy to design in SCR; hence, although there is indication to specific industries, and foci of risk, this could be explored further.

This review of SCRM identifies various research gaps and directions for future research to develop theory and a practical understanding of SCR.

The current literature on SCR has been assessed based on its definition and utilization. The current paper bridges this gap by synthesizing the diverse academic journal papers into the categories based on the design continuum, relationship continuum, process continuum and economic continuum. In addition, it highlights the gaps in industry context, theoretical contribution, geographic location, and research methods applied and addresses the scope for further research.

Increased demand and the pressure to reduce health-care costs have led to longer waiting time for patients to make appointments and during the day of hospital visits. The purpose of this study is to identify opportunities to reduce waiting time using lean techniques and discrete-event simulation (DES).

A five-step procedure is proposed to facilitate the effective utilization of lean and DES to improve the performance of the Otolaryngology Head and Neck Surgery Outpatient Clinic at Cleveland Clinic Abu Dhabi. While lean techniques were applied to reduce the potential sources of waste by aligning processes, a DES model was developed to validate the proposed solutions and plan patient arrivals under dynamic conditions and different scenarios.

Aligning processes resulted in an efficient patient flow reducing both waiting times. DES played a complementary role in verifying lean solutions under dynamic conditions, helping to plan the patient arrivals and striking a balance between the waiting times. The proposed solutions offered flexibility to improve the clinic capacity from the current 176 patients up to 479 (without violating the 30 min waiting time policy) or to reduce the patient waiting time during the visit from the current 33 min to 4.5 min (without violating the capacity goal of 333 patients).

Proposing and validating lean solutions require reliable data to be collected from the clinic and such a process could be laborious as data collection require patient and resource tracing without interfering with the regular functions of the clinic.

The work enables health-care managers to conveniently conduct a trade-off analysis and choose a suitable inter-arrival time – for every physician – that would satisfy their objectives between resource utilization (clinic capacity) and average patient waiting time.

Successful implementation of lean requires a supportive and cooperative culture from all stakeholders involved.

This study presents an original and detailed application of lean techniques with DES to reduce patient waiting times. The adopted approach in this study could be generalized to other health-care settings with similar objectives.

The purpose of this paper is to fabricate a new Cu-Sn-Ni-Cu interconnection microstructure for electromigration studies in 3D integration.

The Cu-Sn-Ni-Cu interconnection microstructure is fabricated by a three-mask photolithography process with different electroplating processes. This microstructure consists of pads and conductive lines as the bottom layer, Cu-Sn-Ni-Cu pillars with the diameter of 10-40 μm as the middle layer and Cu conductive lines as the top layer. A lift-off process is adopted for the bottom layer. The Cu-Sn-Ni-Cu pillars are fabricated by photolithography with sequential electroplating processes. To fabricate the top layer, a sputtered Cu layer is introduced to prevent the middle-layer photoresist from being developed. With the final Cu electroplating processes, the Cu-Sn-Ni-Cu interconnection microstructure is successfully achieved.

The surface morphology of Cu-Sn pillars consists of densely packed clusters which are formed by an ordered arrangement of tetragonal Sn grains. The diffusion of Cu atoms into the Sn phases is observed at the Cu/Sn interface. Furthermore, the obtained Cu-Sn-Ni-Cu pillars have a flat surface with an average roughness of 13.9 nm. In addition, the introduction of Ni layer between the Sn and the top Cu layers in the Cu-Sn-Ni-Cu pillars can mitigate the diffusion of Cu atoms into Sn phases. The process is verified by checking the electrical performance using four-point probe measurements.

The method described in this paper which combined a three-mask photolithography process with sequential Cu, Sn, Ni and Cu electroplating processes provides a new way to fabricate the interconnection microstructure for future electromigration studies.

Due to the influence of complex and intersecting factors, self-governed public open spaces (POSs) (managed by local communities) are subject to collective action dilemmas such as tragedy of the commons (overexploitation), free-riding, underinvestment and mismanagement. This review paper adopts a multi-dimensional and multi-tier social-ecological system (SES) framework proposed by McGinnis and Ostrom, drawing on collective action theory to explore the key institutional-social-ecological factors that impact POS self-governance.

In this paper, Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) was utilized to systematically screen and review the relevant literature for the period from 2000 to 2023 in three databases: Web of Science, Scopus and Google Scholar. A total of 57 papers were chosen for in-depth analysis.

The literature review identified and categorized several variables associated with the self-organizing system of POS; consequently, an SES-based POS management framework was developed for the first time, consisting of 114 institutional-social-ecological sub-variables from different dimensions and three levels. Compared to ecological factors, among others, governance organizations, property-rights systems, socioeconomic attributes and actors' knowledge of SES have been commonly and primarily studied.

There is still room for the refinement of the conceptual SES-based POS collective action framework over the time (by adding in new factors), and indefinitely empirical research validating those identified factors is also worth to be undertaken, particularly testing how SES factors and interaction variables affect the POS quality (collective action).

The findings of this study can provide local policy insights and POS management strategies based on the identification of specific SES factors for relevant managers. Moreover, this research makes significant theoretical contributions to the integration of the SES framework and collective action theory with POS governance studies.