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This paper aims to propose an enhanced static model of commercial braided pneumatic artificial muscles (PAMs), which is fully analytical without the need for experimentally determined parameters.

To address the highly nonlinear issues of PAMs, the enhanced model is derived considering the irregular shapes close to their end-fittings, as well as the elastic energy stored in both their braids and rubber bladders. The hysteresis characteristics of PAMs are also explored by analyzing the friction in the crossovers of the interlacing braided strands, together with that between the strands and their surrounding bladders. The isobaric and isometric experiments of a commercial PAM are conducted to demonstrate the enhancement, and the model accuracy is evaluated and compared with some existing models in terms of root mean square errors (RMSEs). Additionally, the proposed model is simplified to facilitate the applications that entail high computational efficiency.

The proposed model agrees well with the experimental results, which indicates its viability to accurately predict the static behaviors. An overall RMSE of 5.24 N shows that the enhanced model is capable of providing higher accuracy than the existing analytical models, while keeping the modeling cost at a minimum.

The proposed model, taking account of non-cylindrical shapes, elastic energy and friction, succeeds in enhancing the static predictions of commercial PAMs. The fully analytical model may accelerate the development of novel PAM-based robots for high-precision control, while giving a deeper understanding of commercial PAMs.

The purpose of this paper is to investigate the presence of bladder and bowel symptoms in women recently imprisoned in Western Australian prisons, specifically; stress, urge and mixed urinary incontinence, faecal incontinence, nocturia, nocturnal enuresis and constipation and the impact on the quality of life (QOL).

Over a 12-month period 29 women, recently released from Western Australia’s female prisons, were surveyed using a questionnaire previously validated for the prison population. The Short Form King’s Health Questionnaire and a modified version of the Manchester Health Questionnaire were used to assess the effects of these symptoms on QOL.

Of those surveyed only one respondent reported having no bladder or bowel symptoms following release from prison. Trends assessed by Chi-square analysis suggest women imprisoned for any period of time are more likely to develop both bladder and bowel symptoms which persist after release back into the community. A history of substance or alcohol abuse is often concurrent with the presence of symptoms. QOL scores are also lower for those reporting either bladder or bowel symptoms affecting total scores and the domains of both activities of daily living and mental health.

Women imprisoned for any length of time developed bladder and bowel symptoms which had a negative impact on their QOL. Larger studies need to be conducted to investigate these trends and whether small changes in conservative measures can influence outcomes.

The purpose of this paper is to formulate a benchmark to increase the tyre curing press production rate while minimizing tyre curing press downtime and maintenance cost with the help of a maintenance management technique based on overall equipment effectiveness (OEE).

The methodology is based on determining the OEE of tyre curing press before and after rectifying the causes of failures. The failure mode and effect analysis (FMEA) technique is used to find out the root causes of repetitive failures in tyre curing press by using the risk priority number.

A significant change in the value of OEE is observed after rectifying the repetitive failures, which were determined using the FMEA technique. Thus, it is concluded that the OEE and FMEA assist in improving the industrial performance and competitiveness of the production equipment studied.

This study is limited to determining the OEE of single equipment only, not the whole production system. Manufacturing facilities are dependent on the operating environment; therefore a comparison of two different manufacturing plants based on the OEE value would not be justified.

This study can be applied in any tyre manufacturing industry in order to take competitive benefits, such as reduction in equipment downtime, increased production and reduction in maintenance cost.

The angle from which the paper approaches the bottleneck problem in a tyre production line is original for the studied company and shows positives results. It allows the company to apply the same approach in its other production equipment, lines and factories to achieve improvement in industrial performance and competitiveness.

Intravesical therapy (IVeT) plays an increasingly important role in contemporary management of “high‐risk” superficial bladder cancer. Through audit this study aims to highlight points in patient care where improvements could be made. Based on preliminary audit data the authors developed a novel, integrated patient‐care pathway (ICP) to target areas of weakness. The impact of ICP implementation was then assessed prospectively.

The clinical course of 60 patients receiving IVeT was examined (34 men, 16 women; mean age: 73 years, range 52‐96). Complete data were available for 50 patients (mean follow‐up 51 months, range 6‐256; preliminary audit n=30, re‐audit n=20). In total 444 instillations of IVeT were administered.

Initial data highlighted several areas of deficiency including poor communication, inadequate urinalysis, low treatment compliance, delayed cystoscopic re‐evaluation and deficiencies in follow‐up. After implementation of the ICP, re‐audit confirmed marked improvements in all variables examined.

By rapid implementation of a simple, reproducible and comprehensive process of documentation the paper has demonstrated meaningful improvements in standards of care for this complex group of patients.

Through rigorous audit the paper identified areas of poor performance in the management of patients receiving IVeT. Using these data the authors modified clinical practice and strengthened the authors service provision for patients with “high‐risk” superficial bladder cancer.

October 31, 1972 Negligence — Duty of care — Manufacturer — Purchaser's employees exposed to chemical containing carcinogen — Whether danger foreseeable.

This paper aims to devise a first-of-its-kind methodology to determine the design, operating conditions and actuation strategy of pneumatic artificial muscles (PAMs) for assistive robotic applications. This requires extensive characterization, data set generation and meaningful modelling between PAM characteristics and design variables. Such a characterization should cover a wide range of design and operation parameters. This is a stepping stone towards generating a design guide for this highly popular compliant actuator, just like any conventional element of a mechanism.

Characterization of a large pool of custom fabricated PAMs of varying designs is performed to determine their static and dynamic behaviours. Metaheuristic optimizer-based artificial neural network (ANN) structures are used to determine eight different models representing PAM behaviour. The assistance of knee flexion during level walking is targeted for evaluating the applicability of the developed actuator by attaching a PAM across the joint. Accordingly, the PAM design and the actuation strategy are optimized through a tabletop emulator.

The dependence of passive length, static contraction, dynamic step response for inflation and deflation of the PAMs on their design dimensions and operating parameters is successfully modelled by the ANNs. The efficacy of these models is investigated to successfully optimize the PAM design, operation parameters and actuation strategy for using a PAM in assisting knee flexion in human gait.

Characterization of static and the dynamic behaviour of a large pool of PAMs with varying designs over a wide range of operating conditions is the novel feature in this article. A lucid customizable fabrication technique is discussed to obtain a wide variety of PAM designs. Metaheuristic-based ANNs are used for tackling high non-linearity in data while modelling the PAM behaviour. An innovative tabletop emulator is used for investigating the utility of the models in the possible application of PAMs in assistive robotics.

Contemporary Anglo-American economics, which I admire, faces two major obstacles. First, in its drive at least since Milton Freedman to be a positive science free of normative issues, it ignores its own current intellectual foundations buried at the heart of its analysis of the “advantages of trade”: Fairness. Second, the major driver of economic growth in the past 50,000 years has been the explosion of goods and production capacities from perhaps 1,000 to 10,000 long ago, to perhaps 10 billion goods and production capacities today. Economics, lacking a theory for this explosion, deals with this explosion by ignoring it and treating it as “exogenous” to its theory.

The “Edgeworth Box” carries the heart of advantages of trade, demonstrating for properly curved isoutility curves a region where you and I are better-off trading some of my apples for some of your pears. The ratio of these in trade constitutes price. But spanning the region of advantages of trade is the famous CONTRACT CURVE, where we have exhausted all the advantages of trade. Different points on the curve correspond to different prices. But the Contract Curve is Pareto Optimal, motion on the curve can only make one of us better-off at the expense of the other. Critically, economics has NO THEORY for where we end up on the Contract Curve. Nor, since different points on the curve correspond to different prices, can PRICE settle the issue.

Using the Ultimatum Game I will show that FAIRNESS typically drives where we settle on the Contract Curve, as long as we do not have to trade with one another. Thus ethics enters economics at its foundation, yet cannot be mathematized, so is ignored in Freedman’s name of a positive science.

Perhaps more important, unlike physics, no laws entail the evolution of either the biosphere or the “econosphere.” There are no laws of motion whose integration would entail that evolution. Lacking an entailing theory of the growth of the economy in diversity, often of new goods and production capacities, economists ignore the most important feature of economic growth, wrongly treating it as “exogenous.”

The failures above are likely to play major roles in the lapse to mere greed in our major financial institutions, and in our inadequate capacities to help drive growth in much of the poverty-struck world.