Presents algorithms for determining the paths employed by the Proteus rapid prototyping system when building three‐dimensional parts. Proteus is a fused deposition modeling system…
Abstract
Presents algorithms for determining the paths employed by the Proteus rapid prototyping system when building three‐dimensional parts. Proteus is a fused deposition modeling system that extrudes a thermoplastic in beads through a nozzle. Determines within each layer of the layered manufacturing process, the material deposition paths as well as the regions where local structures are required to support these paths. Computes the paths with the goal of reducing the amount of supports needed to build the physical prototype of the part by taking advantage of the two novel manufacturing techniques of shelving and bridging that had been developed previously. The path planning algorithms presented are designed to utilize the above techniques and address the variety of conditions that appear in practice allowing the Proteus system to “build in air”.
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V.T. Rajan, Vijay Srinivasan and Konstantinos A. Tarabanis
Many engineering and scientific problems require the filling of a two‐dimensional region with scan lines of finite width. The number of contiguous scan line segments required for…
Abstract
Many engineering and scientific problems require the filling of a two‐dimensional region with scan lines of finite width. The number of contiguous scan line segments required for the filling depends on the direction used for scanning. When the cost of the filling operation increases with the number of scan line segments, as is the case in numerically controlled machining, layered fabrication and computer graphics applications, then it is desirable to select a direction that minimizes this number. In this paper we provide a method for efficiently computing such an optimal direction when the region to be filled is bounded by straight‐line segments and/or circular arcs.
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Evangelos Kalampokis, Efthimios Tambouris and Konstantinos Tarabanis
The purpose of this paper is to consolidate existing knowledge and provide a deeper understanding of the use of social media (SM) data for predictions in various areas, such as…
Abstract
Purpose
The purpose of this paper is to consolidate existing knowledge and provide a deeper understanding of the use of social media (SM) data for predictions in various areas, such as disease outbreaks, product sales, stock market volatility and elections outcome predictions.
Design/methodology/approach
The scientific literature was systematically reviewed to identify relevant empirical studies. These studies were analysed and synthesized in the form of a proposed conceptual framework, which was thereafter applied to further analyse this literature, hence gaining new insights into the field.
Findings
The proposed framework reveals that all relevant studies can be decomposed into a small number of steps, and different approaches can be followed in each step. The application of the framework resulted in interesting findings. For example, most studies support SM predictive power, however, more than one-third of these studies infer predictive power without employing predictive analytics. In addition, analysis suggests that there is a clear need for more advanced sentiment analysis methods as well as methods for identifying search terms for collection and filtering of raw SM data.
Originality/value
The proposed framework enables researchers to classify and evaluate existing studies, to design scientifically rigorous new studies and to identify the field's weaknesses, hence proposing future research directions.
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Eleni Panopoulou, Efthimios Tambouris and Konstantinos Tarabanis
In this paper, the aim is to develop a framework for evaluating the web sites of public authorities. The proposed framework consists of four axes: two for assessing the general…
Abstract
Purpose
In this paper, the aim is to develop a framework for evaluating the web sites of public authorities. The proposed framework consists of four axes: two for assessing the general characteristics and content of the web sites (namely general characteristics and e‐content); and two for assessing specific functionalities addressing their governmental character (namely e‐services and e‐participation).
Design/methodology/approach
The proposed framework is gradually built through a critical analysis of the two relevant domains, web site evaluation and e‐government. The methodology used in the case study includes the construction of an appropriate questionnaire for assessing the framework metrics. The practical use of the framework is demonstrated by means of a case study, namely evaluating the web sites of Greek public authorities at local and regional level.
Findings
The proposed framework presents a more holistic approach to e‐government web site evaluation, while the case study provides some interesting results with regards to the shortcomings of Greek public authority web sites.
Research limitations/implications
The proposed framework could be further enhanced by incorporating an evaluation of the demand site of e‐government. Moreover, a more thorough approach with regard to privacy would have to include metrics to be answered directly by IT security personnel.
Practical implications
The proposed framework can be used for evaluating the web sites of public authorities in a more comprehensive way. As an example, the case study reveals significant results of practical importance by indicating overall progress, aspects that are under‐developed, etc.
Originality/value
This paper provides a novel framework to e‐government web site evaluation that also considers e‐government services and e‐participation. We anticipate that it will be of interest to both researchers and practitioners alike.
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Eleni Kaliva, Eleni Panopoulou, Efthimios Tambouris and Konstantinos Tarabanis
The purpose of this paper is to develop a domain model for online community building and collaboration in e‐government and policy modelling.
Abstract
Purpose
The purpose of this paper is to develop a domain model for online community building and collaboration in e‐government and policy modelling.
Design/methodology/approach
The authors followed a structured approach including five distinct steps: define the domain to be investigated; collect domain knowledge from both existing online community building and collaboration platforms and domain experts; analyse the gathered knowledge; develop and evaluate the domain model.
Findings
A domain model was developed for community building and collaboration in eGovernment and policy modelling, including the domain definition, the domain lexicon and the conceptual models modelling its basic entities and functions of the domain. In particular, the UML class diagram was used for modelling the domain entities and the UML use cases diagram for modelling the domain functions.
Originality/value
A literature search revealed a lack of domain models for online community building and collaboration, not only in e‐government and policy modelling but also in general. The proposed model provides a better understanding of the domain. It can also be used in the development of relevant platforms, leading to the reduction of software development costs and delivery time, as well as the improvement of software quality and reliability, by minimising domain analysis errors.
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Houda Chakiri, Mohammed El Mohajir and Nasser Assem
Most local governance assessment tools are entirely or partially based on stakeholders’ surveys, focus groups and benchmarks of different local governments in the world. These…
Abstract
Purpose
Most local governance assessment tools are entirely or partially based on stakeholders’ surveys, focus groups and benchmarks of different local governments in the world. These tools remain a subjective way of local governance evaluation. To measure the performance of local good-governance using an unbiased assessment technique, the authors have developed a framework to help automate the design process of a data warehouse (DW), which provides local and central decision-makers with factual, measurable and accurate local government data to help assess the performance of local government. The purpose of this paper is to propose the extraction of the DW schema based on a mixed approach that adopts both i* framework for requirements-based representation and domain ontologies for data source representation, to extract the multi-dimensional (MD) elements. The data was collected from various sources and information systems (ISs) deployed in different municipalities.
Design/methodology/approach
The authors present a framework for the design and implementation of a DW for local good-governance assessment. The extraction of facts and dimensions of the DW’s MD schema is done using a hybrid approach, where the extraction of requirement-based DW schema and source-based DW schema are done in parallel followed by the reconciliation of the obtained schemas to obtain the good-governance assessment DW final design.
Findings
The authors developed a novel framework to design and implement a DW for local good-governance assessment. The framework enables the extraction of the DW MD schema by using domain ontologies to help capture semantic artifacts and minimize misconceptions and misunderstandings between different stakeholders. The introduction and use of domain ontologies during the design process serves the generalization and automation purpose of the framework.
Research limitations/implications
The presently conducted research faced two main limitations as follows: the first is the full automation of the design process of the DW and the second, and most important, is access to local government data as it remains limited because of the lack of digitally stored data in municipalities, especially in developing countries in addition to the difficulty of accessing the data because of regulatory aspects and bureaucracy.
Practical implications
The local government environment is among the public administrations most subject to change-adverse cultures and where the authors can face high levels of resistance and significant difficulties during the implementation of decision support systems, despite the commitment/engagement of decision-makers. Access to data sources stored by different ISs might be challenging. While approaching the municipalities for data access, it was done in the framework of a research project within one of the most notorious universities in the country, which gave more credibility and trust to the research team. There is also a need for further testing of the framework to reveal its scalability and performance characteristics.
Originality/value
Compared to other local government assessment ad hoc tools that are partially or entirely based on subjectively collected data, the framework provides a basis for automated design of a comprehensive local government DW using e-government domain ontologies for data source representation coupled with the goal, rationale and business process diagrams for user requirements representations, thus enabling the extraction of the final DW MD schema.