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This paper attempts to construct a public‐key coding system using grey generation and braid group.

The identification (ID) codes of both sides for communication are public for everyone and considered as public keys. Starting from the ID code of both sides of communication, the temporary secret key of communication can be obtained by the grey 1‐AGO algorithm first. Then the new formal common secret key can be obtained by using the element exchangeability of the braid group during the exchanging process of the temporary secret key between two sides of communication. The paper presents an exchange protocol of secret key based on grey data generation and braid group. It also constructs a cipher communication system by using Hash function based on the exchange protocol of secret key last.

The exchange protocol of secret key and the system of cipher communication which are proposed in this paper make use of the difficult problem of resolving disper se logarithm from generated code to ID code and the conjugate problem which is not ever resolved in braid group, which can ensure the security of the algorithm theoretically.

The main steps of the exchange protocol and cipher communication system in this paper can be achieved through a computer program. They can be used in many communication processes on the internet.

The paper succeeds in realising both secret key generation and exchanging protocol of communication by using grey systems theory and braid group properties.

The use of algebraic languages such as REDUCE makes possible the automatic generation, from fairly concise data, of the main families of two and three dimensional C0 continuous finite element shape functions, with a high confidence in their correctness. This paper gives a tutorial introduction to the REDUCE language and describes how it was used to generate shape function routines.

Effective strategic internal communication is instrumental for meaningful relationships and productive work climates within organizations and, therefore, for overall organizational success. Currently, demographic shifts, the dramatically changing work environments because of pandemics and technology, and longer working lives challenge internal communication experts to assess the implications of generational differences for respective workforce target audiences. Effectively addressing the target audiences requires a focus on and understanding of their needs and behaviours. Surprisingly, little research has been conducted on the segmentation criteria of internal stakeholders, and even less on the implications of different generations for internal communication management. This study is novel as it discusses the value and practicality of different generations as a segmentation criterion for effective internal communication from the perspective of internal communication professionals. A multi-method qualitative research approach was employed, including 49 unstructured interviews, eight focus groups and 13 semi-structured interviews with internal communication professionals in Swiss companies on a strategic and operational level. The results show, first, that the segmentation of the internal audiences is dominated by traditional one-dimensional top-down stakeholder-oriented approaches. Second, while an awareness of the importance of generations is high and the need for multi-dimensional segmentation is evident, formal segmentation by generation is rarely implemented and remains controversial. Third, internal communication can foster more inclusive and productive workplaces by better considering the needs and preferences of the different internal segments and by simultaneously standardizing and customizing communication. The study also discusses inherent limitations and suggests avenues for future research.

Non-uniform rational B-splines (NURBSs) are the de facto standard for representing objects in computer-aided design (CAD). The purpose of this paper is to discuss how to stick to this standard in all phases of the additive manufacturing (AM) workflow, from the CAD object to the final G-code, bypassing unnecessary polygonal approximations.

The authors use a commercial CAD system (Rhino3D along with its programming environment Grasshopper) for direct slicing of the model, offset generation and trimming. Circular arcs are represented as quadratic NURBSs and free-form geometry as quadratic or cubic polynomial B-splines. Therefore, circular arcs are directly expressible as G2/G3 G-code commands, whereas free-form paths are rewritten as a succession of cubic Bézier curves, thereby admitting exact translation into G5 commands, available in firmware for AM controllers, such as Marlin.

Experimental results of this paper confirm a considerable improvement in quality over the standard AM workflow, consisting of an initial polygonization of the object (e.g. via standard tessellation language), slicing this polygonal approximation, offsetting the polygonal sections and, finally, generating G-code made up of polyline trajectories (G1 commands).

A streamlined AM workflow is obtained, with a seamless transfer from the initial CAD description to the final G-code. By adhering to the NURBS standard at all steps, the authors avoid multiple representations and associated errors resulting from approximations.

The rapid development of three-dimensional (3D) printing makes it familiar in daily life, especially the fused deposition modeling 3D printers. The process planning of traditional flat layer printing includes slicing and path planning to obtain the boundaries and the filling paths for each layer along the vertical direction. There is a clear division line through the whole fabricated part, inherited in the flat-layer-based printed parts. This problem is brought about by the seam of the boundary in each layer. Hence, the purpose of this paper is to propose a novel helical filling path generation with the ideal surface-plane intersection for a rotary 3D printer.

The detailed algorithm and implementation steps are given with several worked examples to enable readers to understand it better. The adjacent points obtained from the planar slicing are combined to generate each layer's helical points. The contours of all layers are traversed to obtain the helical surface layer and helical path. Meanwhile, the novel rotary four-degree of freedom 3D printer is briefly introduced.

As a proof of concept, this paper presents several examples based on the rotary 3D printer designed in the authors’ previous research and the algorithms illustrated in this paper. The preliminary experiments successfully verify the feasibility and versatility of the proposed slicing method based on a rotary 3D printer.

This paper provides a novel and feasible slicing method for multi-axis rotary 3D printers, making manufacturing thin-wall and complex parts possible. To further broaden the proposed slicing method’s application in further research, adaptive tool path generation for flat and curved layer printing could be applied with a combination of flat and curved layers in the same layer, different layers or even different parts of structures.

In recent days, rapid machining through digital prototyping has been popular for its applicability in a wide range of complex and useful parts. Rapid construction of prototypes from point cloud data based on section plane method is available, which is an approximate method. Discusses some suitable methodology for conversion of point cloud data to a physical prototype where data acquisition is through a mechanical touch trigger probing process using CNC milling machine. The process is quite useful for reverse engineering of complex sculptured parts. A concept called tangent plane method is adopted for the generation of 3D geometry on point cloud data of sculptured parts with due emphasis on probe radius compensation after data capture and tool radius compensation during tool‐path generation. Computer simulated results are presented, based on real‐world point cloud data.

Ubiquitous web applications (UWA) are a new type of web applications which are accessed in various contexts, i.e. through different devices, by users with various interests, at anytime from anyplace around the globe. For such full‐fledged, complex software systems, a methodologically sound engineering approach in terms of model‐driven engineering (MDE) is crucial. Several modeling approaches have already been proposed that capture the ubiquitous nature of web applications, each of them having different origins, pursuing different goals and providing a pantheon of concepts. This paper aims to give an in‐depth comparison of seven modeling approaches supporting the development of UWAs.

This methodology is conducted by applying a detailed set of evaluation criteria and by demonstrating its applicability on basis of an exemplary tourism web application. In particular, five commonly found ubiquitous scenarios are investigated, thus providing initial insight into the modeling concepts of each approach as well as to facilitate their comparability.

The results gained indicate that many modeling approaches lack a proper MDE foundation in terms of meta‐models and tool support. The proposed modeling mechanisms for ubiquity are often limited, since they neither cover all relevant context factors in an explicit, self‐contained, and extensible way, nor allow for a wide spectrum of extensible adaptation operations. The provided modeling concepts frequently do not allow dealing with all different parts of a web application in terms of its content, hypertext, and presentation levels as well as their structural and behavioral features. Finally, current modeling approaches do not reflect the crosscutting nature of ubiquity but rather intermingle context and adaptation issues with the core parts of a web application, thus hampering maintainability and extensibility.

Different from other surveys in the area of modeling web applications, this paper specifically considers modeling concepts for their ubiquitous nature, together with an investigation of available support for MDD in a comprehensive way, using a well‐defined as well as fine‐grained catalogue of more than 30 evaluation criteria.

The purpose of this paper was to examine changes in the contents of Canadian corporate codes of ethics over a period of two decades from an institutionalization perspective.

The paper tracks changes in the contents of the codes of large Canadian corporations longitudinally by analyzing their contents at two points over two decades, in 1992 and 2012. In particular, the paper tests three hypotheses related to the institutionalization of codes.

It was found that the codes have become more prescriptive, they are more concerned with social responsibility and are more likely to identify their moral and legal authority. Overall, the findings support an institutional interpretation of the observed changes.

While large corporations are critical in establishing new and innovative management practices, their selection as the study population limits the generalizabilty of the findings. Another limitation of this paper is that it used an a priori determined set of items to analyze the contents of the codes and while this was needed to facilitate the comparison across time, it also meant that some important items were not clearly identified.

Codes of ethics are the foundation of ethics programs in corporations and their contents could be critical in the development of a culture of ethics in corporations. This paper makes a valuable contribution to research on business ethics by analyzing the codes of ethics of the largest corporations in Canada at two points over two decades. The need to track changes in corporate codes of ethics over time has been advocated by several researchers, but longitudinal studies in this area are rare.