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A novel model of the upper arm under transcutaneous electrical stimulation with multi-pad electrodes is presented and experimentally validated. The model aims at simulating and analysing the effects of surface electrical stimulation on biceps brachii. The paper aims to discuss these issues.

Both the passive properties of tissues surrounding nerve bundles and the active characteristics of the nervous system are included. The output of the proposed model is nerve recruitment and muscle contraction.

Simulations and experimental tests on six healthy young adults have been conducted and results show that the proposed model gives information on electrically elicited muscle contraction in accordance with in-vivo tests and literature on motor unit recruitment order. Tests with different electrodes configurations show that the spatial distribution of active electrodes is a critical factor in electrically elicited muscle contractions, and that multi-pad electrodes can optimise the stimulation effectiveness and patient comfort with sequences of biphasic pulses of 350 μs at 30 pulses/s and threshold values of 2 mA.

Results encourage the use of the proposed model of the upper arm as a valid and viable solution for predicting the behaviour of the neuromuscular system when surface electrical stimulation is applied, thus optimising the design of neuroprosthetics.

This paper re-examines the ontology of documents, especially digital ones, in the context of preservation, which presumes the actual existence of things. It also explores which aspects of documents are retained or lost over the course of time.

This study detangles the complexities of existential dependence relations of documents, by selectively reviewing literature on digital preservation, document theory, John Searle's social ontology, Maurizio Ferraris' documentality, and Amie Thomasson's categorial ontology.

The author argues that (1) existing objects can be documents, insofar as perceivers regard them as such; (2) documents are social objects as they depend on other objects, including creators, perceivers, and other documents; and (3) preserving digital documents entails the curation of dependence relations since they inherently have technologically dependent relations.

A clarification of the existential dependence relations of documents can aid documentary heritage institutions in determining preservation goals and strategies. Future research must address how, and to what extent, such dependence relations can be curated.

This paper clarifies that the preservation of documents entails the curation of dependence relations, and the critical issue in preservation is how to best preserve the dependence relations of documents, especially since digital documents available on the Internet inherently have technological and dynamic dependence relations.

By engaging with recent debates between management historians over social constructionism, this paper aims to show the merits of adopting a new realist ontology of the business enterprise. In contrast with ANTi-History, the purpose is to provide a philosophically rigorous conception of social objects and to argue that enterprises are a member of this category.

Insights from Maurizio Ferraris’s documentality theory and Graham Harman’s philosophy of social objects are used to identify the ontological forming ground and developmental pathway of an Antipodean stevedoring company that operated prior to the deregulation of New Zealand’s ports in 1989.

With regard to social entities in general and firms in particular, continental philosophy’s resurgent realist movement provides a history-aware social ontology that incorporates the grain of truth lying within social constructionism. As exemplified by the writings of Ferraris and Harman, realism provides a viable conception of social objects and, in so doing, a more coherent ontological foundation for the business enterprise than the relational ontology embraced by management history ANTians.

By drawing on two realist perspectives hitherto neglected by management historians, this paper resolves disagreements about the ontology of the business enterprise.

In a kitting supply system, the occurrence of material-handling errors is unavoidable and will cause serious production losses to an assembly line. To minimize production losses, this paper aims to present a dynamic scheduling problem of automotive assembly line considering material-handling mistakes by integrating abnormal disturbance into the material distribution problem of mixed-model assembly lines (MMALs).

A multi-phase dynamic scheduling (MPDS) algorithm is proposed based on the characteristics and properties of the dynamic scheduling problem. In the first phase, the static material distribution scheduling problem is decomposed into three optimization sub-problems, and the dynamic programming algorithm is used to jointly optimize the sub-problems to obtain the optimal initial scheduling plan. In the second phase, a two-stage rescheduling algorithm incorporating removing rules and adding rules was designed according to the status update mechanism of material demand and multi-load AGVs.

Through comparative experiments with the periodic distribution strategy (PD) and the direct insertion method (DI), the superiority of the proposed dynamic scheduling strategy and algorithm is verified.

To the best of the authors’ knowledge, this study is the first to consider the impact of material-handling errors on the material distribution scheduling problem when using a kitting strategy. By designing an MPDS algorithm, this paper aims to maximize the absorption of the disturbance caused by material-handling errors and reduce the production losses of the assembly line as well as the total cost of the material transportation.

Flexible automated assembly is an emerging need in several industries. The purpose of this paper is to address the introduction of an innovative concept in flexible assembly: the fully flexible assembly system (F‐FAS).

After an analysis of the state of the art, the authors describe the proposed F‐FAS, from a layout, constitutional elements, functioning principles and working cycle point of view. Second, the authors compare the traditional FAS and the manual assembly system versus the proposed F‐FAS according to their throughput and unit production costs, deriving a convenience map as a function of the number of components used in assembly and of the efficiency of the F‐FAS. Finally, using a prototype work cell developed at the Robotics Laboratory of University of Padua, the authors validate the F‐FAS concept.

Results of the research indicate that the concept of full‐flexibility can be exploited to bring automation to a domain where traditional FAS are not competitive versus manual assembly. In fact, the F‐FAS outperforms both traditional FAS and manual assembly, in terms of unit direct production costs, when the size of the batch is small, the number of components used in assembly is large and the efficiency of the F‐FAS is reasonably high. The F‐FAS prototype demonstrated the possibility of working, for certain conditions (models/components/production mix), in the F‐FAS convenience area, highlighting the achievable cost reduction versus traditional assembly systems.

The novelty of the study lies in the F‐FAS concept, its performances in terms of flexibility, compactness, throughput and unit direct production costs. A prototype work cell validated the concept and demonstrated its viability versus traditional assembly systems, thanks to convenience analysis.

The paper aims to address the modelling and optimization of fully flexible assembly systems (F‐FAS), a new concept in flexible automation recently introduced by the authors.

The paper presents a mathematical model of the F‐FAS, which makes it possible to predict its efficiency, throughput and unit direct production costs, correlating such values with system and production variables. The mathematical model proposed in the paper was derived from experimental and simulation data, which were analysed for a wide range of different productions and system settings.

Correlation analysis revealed that there are three main determinants of the efficiency of the F‐FAS: the number of components (types of parts) used to assemble the models (production variable); the average complexity of the models to be assembled (production variable); the ratio of the average perimeter of components (production variable) over a significant dimension of the working plane (system variable). Such parameters makes it possible to estimate the maximum attainable efficiency of the F‐FAS, and to calculate the optimal setting of the feeder which makes it possible to obtain such efficiency during the execution of the whole production order.

The model presented in the paper makes it possible to quantify in advance the real potential of the F‐FAS, according to the characteristics of the production mix and type of components to be assembled. By using the methodologies presented in the paper, one can first evaluate the convenience of the F‐FAS approach with respect to traditional FAS technology and manual assembly, then identify the optimal design and settings of the F‐FAS, according to the needs of a specific application. As a result, not only can the investment on the automated assembly system be accurately evaluated in advance, but also the return on investment can be maximized.

The purpose of this paper is to explore a hybrid model of the consumption of organic foods, combining the use of exploratory factor analysis (EFA) and an artificial neural network (ANN).

The study has three phases. In the first phase, the Delphi method is employed, and 15 motives for the consumption of organic food are identified; these motives are used to develop the model in the second phase. Finally, in the last phase, an ANN is used to rank the motives to determine their priority.

The EFA model explored includes four factors that have a positive effect on the level of organic food consumption. These are naturalness, trust, sanitariness and marketing. Results from the use of an ANN indicate that the main variables in organic food consumption are claims, psychological variables and doubt. From the results of the EFA model it is clear these three variables are components of the factor of trust.

Marketers can use the model developed in this paper to satisfy the needs of their customers and hence enhance their market share and profitability. This study shows that improvements in truth in the claims made for organic products, perceived security from using these products and doubts about the safety of other foods can lead marketers to their goal. Informative advertisements can inculcate trust and naturalness among consumers as main factors.

The main contribution of this study is the light it sheds on how consumers think about organic foods. It develops a model incorporating motives for consuming organic food and determining the priorities held by consumers of organic foods.