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The purpose of this paper is to propose a web‐based tool that enables the development and provision of learning designs and its reuse and re‐contextualization as generative learning objects, aimed at developing educational materials.

The use of learning objects can facilitate the process of production and delivering of educational material and their reuse and re‐contextualization in different scenarios – such process is due to the current development stage of information and communication technologies (ICTs), which allow easy access to products and services related to them. ICTs combined with instructional design theories, lead to the emergence of new generations of distance learning, which add educational content to web‐based services. From this combination rises a hybrid mode of education, which combines tools for face‐to‐face and distance learning (blended learning).

The use of the web as a platform for production and management of learning objects comes as a solution for storage and sharing. The utilization of objects is justified when its reusability is facilitated. This gives rise to possibilities in a client‐server environment, where information is centralized and available anywhere in the network.

The combination of ICT and instructional design theories has potential and could result in hybrids which are yet to be fully understood and explored. This can enhance blended learning provision.

The paper presents a tool in which the learning designs work as structures built on XML, based on concept maps, which act as an interaction layer between the learning objects, organizing the content to be available.

Recent years have seen a technological change, Industry 4.0, in the manufacturing industry. Human–robot cooperation, a new application, is increasing and facilitating collaboration without fences, cages or any kind of separation. The purpose of the paper is to review mainstream academic publications to evaluate the current status of human–robot cooperation and identify potential areas of further research.

A systematic literature review is offered that searches, appraises, synthetizes and analyses relevant works.

The authors report the prevailing status of human–robot collaboration, human factors, complexity/ programming, safety, collision avoidance, instructing the robot system and other aspects of human–robot collaboration.

This paper identifies new directions and potential research in practice of human–robot collaboration, such as measuring the degree of collaboration, integrating human–robot cooperation into teamwork theories, effective functional relocation of the robot and product design for human robot collaboration.

This paper will be useful for three cohorts of readers, namely, the manufacturers who require a baseline for development and deployment of robots; users of robots-seeking manufacturing advantage and researchers looking for new directions for further exploration of human–machine collaboration.

The retail food market has been wracked by traumatic changes for more than a decade. In the 1970s A & P, the largest chain at that time, was well on the way to oblivion until rescued in a foreign takeover by the West German firm of Tengleman. Safeway, the 1986 market share leader nationally, chose a leveraged buyout rather than a takeover and currently has many divisions in the U.S. up for sale. Within a year or two, Safeway will be a pale shadow of its former self, because it failed to adapt to intense competition. Kroger, the current industry leader, has already begun closing stores in many major markets. In the meantime, the strong regionals such as Food Lion, Shaw's, Hannaford Bros., Randall's, Smith's, Bruno's, Weiss, Albertsons, Publix, Giant Food, Pueblo International, H. E. Butt, and Hughes, are challenging the largest national chains for market share in carefully chosen fields of battle. Overall, the supermarket industry experienced an after tax return on net worth of 14 percent in 1986.

Nobody concerned with political economy can neglect the history of economic doctrines. Structural changes in the economy and society influence economic thinking and, conversely, innovative thought structures and attitudes have almost always forced economic institutions and modes of behaviour to adjust. We learn from the history of economic doctrines how a particular theory emerged and whether, and in which environment, it could take root. We can see how a school evolves out of a common methodological perception and similar techniques of analysis, and how it has to establish itself. The interaction between unresolved problems on the one hand, and the search for better solutions or explanations on the other, leads to a change in paradigma and to the formation of new lines of reasoning. As long as the real world is subject to progress and change scientific search for explanation must out of necessity continue.

The purpose of this paper is to investigate efficient designs of a shell-and-tube latent thermal energy storage system through an approach based on the analysis of entropy generation. It proposes innovative branched fins to maximize the performance of the system.

A computational fluid dynamic (CFD) model is first used to detail the thermo-fluid dynamic transient behavior of the latent heat storage system. The model account for phase change, buoyancy driven fluid flow and heat transfer during the process of energy retrieval from the storage unit (solidification). The CFD model is then used to evaluate locally the entropy generation rate during the process. On the basis of the insight gathered through the analysis of the entropy generation, the design of the fins is gradually modified aiming at the maximization of the performance of the storage system.

The best fins design leads to a twofold increase of the solidification rate in the latent heat storage unit. The corresponding second-law efficiency shows an increase of 13 percent compared with traditional fins.

The analysis is based on a single tube configuration of the storage system which implies that non-homogeneous effects due to multiple tubes are not considered. Nevertheless, the proposed design procedure is general and could be applied to different configurations of latent heat thermal storage systems.

Entropy generation analysis provides a very useful design approach to develop configurations of latent heat storage systems that may overcome current performance limitations. Also, practitioners in the field may also benefit of the results for improving current installations of energy storage systems.

Entropy generation is adapted and used to find an optimal design for a time dependent process. That is, a geometrical configuration is found for maximizing the performance over a span of time. This is a key aspect of the work because there is a strong trend toward energy systems operating under transient conditions.

This experimental study investigates the connotative (measured) meaning of the concept “auditor independence” within three audit engagement case contexts, including two acknowledged in the literature to represent significant potential threats to independence. The study’s research design utilises the measurement of meaning (semantic differential) framework originally proposed by Osgood et al. (1957). Findings indicate that research participants considered the concept of independence within a two factor cognitive structure comprising “emphasis” and “variability” dimensions. Participants’ connotations of independence varied along both these dimensions in response to the alternative experimental case scenarios. In addition, participants’ perceptions of the auditor’s independence in the three cases were systematically associated with the identified connotative meaning dimensions.

The purpose of this paper is to present a comparison study of cooperative object manipulation control algorithms. To this end, a full comprehensive survey of the existing control algorithms in this field is presented.

Cooperative manipulation occurs when manipulators are mechanically coupled to the object being manipulated, and the manipulators may not be treated as an isolated system. The most important and basic impedance control (IC) strategies for an assumed cooperative object manipulation task are the Augmented Object Model (AOM) control and the multiple impedance control (MIC) which are found based on the IC, where the former is designed based on the object movement, and the latter is designed based on the whole robot movement. Thus, the basis of these two algorithms are fully studied.

The results are fully analyzed, and it is practically verified that the MIC algorithm has the better performance. In fact, the results reveal that the MIC system could successfully perform the object manipulation task, as opposed to the AOM controller: for the same controller gains, the MIC strategy showed better performance than the AOM strategy. This means that because there is no control on the robot base with the AOM algorithm, the object manipulation task cannot be satisfactorily performed whenever the desired path is not within the robot work space. On the other hand, with the MIC algorithm, satisfactory object manipulation is achieved for a mobile robotic system in which the robot base, the manipulator endpoints and the manipulated object shall be moved.

A simple conceptual model for cooperative object manipulation is considered, and a suitable setup is designed for practical implementation of the two ICs.

The basis of these two aspects or these two algorithms is fully studied and compared which is the foundation of this paper. For this purpose, a case study is considered, in which a space free-flying robotic system, which contains two 2-degrees of freedom planar cooperative manipulators, is simulated to manipulate an object using the above control strategies. The system also includes a rotating antenna and camera as its third and fourth arm. Finally, a simple conceptual model for cooperative object manipulation is considered, and a suitable setup is designed for practical implementation of the two ICs.