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1 – 10 of over 4000This study investigates the impact of three parameters such as: number of LED chips, pitch and LED power on the junction temperature of LEDs using a best heat sink configuration…
Abstract
Purpose
This study investigates the impact of three parameters such as: number of LED chips, pitch and LED power on the junction temperature of LEDs using a best heat sink configuration selected according to a lower temperature. This study provides valuable insights into how to design LED arrays with lower junction temperatures.
Design/methodology/approach
To determine the best configuration of a heat sink, a numerical study was conducted in Comsol Multiphysics on 10 different configurations. The configuration with the lowest junction temperature was selected for further analysis. The number of LED chips, pitch and LED power were then varied to determine the optimal configuration for this heat sink. A general equation for the average LED temperature as a function of these three factors was derived using Minitab software.
Findings
Among 10 configurations of the rectangular heat sink, we deduce that the best configuration corresponds to the first design having 1 mm of width, 0.5 mm of height and 45 mm of length. The average temperature for this design is 50.5 C. For the power of LED equal to 50 W–200 W, the average temperature of this LED drops when the number of LED chips reduces and the pitch size decreases. Indeed, the best array-LED corresponds to 64 LED chips and a pitch size of 0.5 mm. In addition, a generalization equation for average temperature is determined as a function of the number of LED chips, pitch and power of LED which are key factors for reducing the Junction temperature.
Originality/value
The study is original in its focus on three factors that have not been studied together in previous research. A numerical simulation method is used to investigate the impact of the three factors, which is more accurate and reliable than experimental methods. The study considers a wide range of values for the three factors, which allows for a more comprehensive understanding of their impact. It derives a general equation for the average temperature of the LED, which can be used to design LED arrays with desired junction temperatures.
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Critics maintain that for profit, business corporations should be more “responsible,” that they should take account of all constituencies affected by their operations and should…
Abstract
Critics maintain that for profit, business corporations should be more “responsible,” that they should take account of all constituencies affected by their operations and should even assume responsibility for broader societal problems which they may only impact tangentially. Defenders of a narrower set corporate goals and constituent interests argue that corporations should be concerned exclusively with maximizing the profits they can earn for shareholders within the law. This controversy regarding corporate goals and stakeholder interests has spanned most of the twentieth century.
Gayithri Jayathirtha, Deborah Fields, Yasmin B. Kafai and Joseph Chipps
The purpose of this paper is to report changes when a classroom-based makerspace moved from face-to-face to an online setting.
Abstract
Purpose
The purpose of this paper is to report changes when a classroom-based makerspace moved from face-to-face to an online setting.
Design/methodology/approach
To better understand changes in teaching maker activities, as they move from face-to-face to online contexts, the authors analyzed video and interview data from six weeks of an introductory computer science high school classroom (38 youth) that was implementing an electronic textiles unit, shifting to asynchronous online teaching and learning during the March 2020 state-wide school closure because of the pandemic. The authors analyzed field notes and videos of face-to-face and online interactions between the teacher and his students in learning to craft and code their electronic textiles projects.
Findings
The analysis revealed changes in the role of physical and code artifacts, in improvising teaching, and channels for communication between the teacher and students.
Research limitations/implications
This study discusses the implications for future pedagogical design and research efforts, as the authors continue to engage youth and work toward designing equitable learning opportunities with maker activities online.
Originality/value
In maker activities such as electronic textiles, youth design, sew and program circuits to make personalized three-dimensional, textile artifacts. However, nearly all research on supporting and teaching making has been conducted in face-to-face settings.
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Ben Light, Christopher P. Holland and Karl Wills
Enterprise resource planning (ERP) software is the dominant strategic platform for supporting enterprise‐wide business processes. However, it has been criticised for being…
Abstract
Enterprise resource planning (ERP) software is the dominant strategic platform for supporting enterprise‐wide business processes. However, it has been criticised for being inflexible and not meeting specific organisation and industry requirements. An alternative, best of breed (BoB), integrates components of standard package and/or custom software. The objective is to develop enterprise systems that are more closely aligned with the business processes of an organisation. A case study of a BoB implementation facilitates a comparative analysis of the issues associated with this strategy and the single vendor ERP alternative. The paper illustrates the differences in complexity of implementation, levels of functionality, business process alignment potential and associated maintenance.
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The purpose of this paper is to explore some of the influences that computer‐mediated communication (CMC) has and could have on the maintenance of interpersonal relationships. In…
Abstract
Purpose
The purpose of this paper is to explore some of the influences that computer‐mediated communication (CMC) has and could have on the maintenance of interpersonal relationships. In doing this, ethical dilemmas and implications that arise from the technical affordances offered to CMC participants are discussed. Relational maintenance is integral to people's everyday lives. Yet, the ethical issues involve in using CMC to support this have not been explicitly explored.
Design/methodology/approach
The concept of relational maintenance will be explored independently and as it relates to CMC and ethics. This paper will examine current literature and briefly discuss a pilot study relevant to these areas. The pilot study consisted of a survey distributed to undergraduate students in non‐platonic long distance and short distance relationships.
Findings
The exploration of prior literature and the findings of a pilot study support the notion that, with the increase of CMC use to maintain relationships follows the potential increase of unethical behavior in this medium. A number of ethical questions have risen that can be used to inform and direct future research.
Originality/value
This paper is original as it explores the concept of ethics from a relational maintenance perspective through electronic communication. It adds value by integrating these three areas and enhancing the understanding of this integration, while providing information of both theoretical and practical relevance.
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Ben Light, Gordon Fletcher and Alison Adam
The purpose of this paper is to investigate information communications technologies (ICT)‐mediated inclusion and exclusion in terms of sexuality through a study of a commercial…
Abstract
Purpose
The purpose of this paper is to investigate information communications technologies (ICT)‐mediated inclusion and exclusion in terms of sexuality through a study of a commercial social networking web site for gay men.
Design/methodology/approach
The paper uses an approach based on technological inscription and the commodification of difference to study Gaydar, a commercial social networking site.
Findings
Through the activities, events and interactions offered by Gaydar, the study identifies a series of contrasting identity constructions and market segmentations that are constructed through the cyclic commodification of difference. These are fuelled by a particular series of meanings attached to gay male sexualities which serve to keep gay men positioned as a niche market.
Research limitations/implications
The research centres on the study of one, albeit widely used, web site with a very specific set of purposes. The study offers a model for future research on sexuality and ICTs.
Originality/value
This study places sexuality centre stage in an ICT‐mediated environment and provides insights into the contemporary phenomenon of social networking. As a sexualised object, Gaydar presents a semiosis of politicised messages that question heteronormativity while simultaneously contributing to the definition of an increasingly globalised, commercialised and monolithic form of gay male sexuality defined against ICT.
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Kathleen Richardson and Sue Hessey
The purpose of this paper is to explore the claim that online communication technologies are detrimental to off‐line communication practices.
Abstract
Purpose
The purpose of this paper is to explore the claim that online communication technologies are detrimental to off‐line communication practices.
Design/methodology/approach
This paper is based on material from focus groups with students from the University of Cambridge and Anglia Ruskin University (ARU), and in‐depth interviews from a mixture of employed people and students. The breakdown is as follows: three focus groups in total are ran, two cohorts of participants were students from University of Cambridge, and the third group from ARU. Six individuals aged between 21 and 36 were interviewed in‐depth on their Facebook use. Questions relating to personal use of Facebook are asked. All names of participants have been changed.
Findings
The research findings show that opportunities for communication are increased by using Facebook. Facebook use also impacts on how other types of communicative technologies are used – such as the phone and email. From the small participant sample, it is founded (with only one exception, the Facebook user had accepted a request from a “stranger” on recommendation from her friend, only to reject this friend within a short time from her network due to his reliability. Since the study, it is founded that one individual who has befriended individuals that were not known to him. When asked about this, he explained that many of these friends were developed after playing online games with them. In his mind, he had built up trust through game‐playing and used this as a measure of their reliability. Whilst he only joined Facebook in early 2008, he has now accumulated over 350 friends.) that off‐line encounters were a prerequisite for a friend connection to be made online in Facebook. Finally, it is founded that the participants rarely interact with the majority of their Facebook friends and it is this dormant archive of relationships that hold the most interest as it provides an archive of relationships that would have dissipated without these technologies.
Originality/value
The key value of the paper lies in understanding this technology as an archive of human relationships.
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This paper aims to provide insights into the moral values embodied by a popular social networking site (SNS), Facebook.
Abstract
Purpose
This paper aims to provide insights into the moral values embodied by a popular social networking site (SNS), Facebook.
Design/methodology/approach
This study is based upon qualitative fieldwork, involving participant observation, conducted over a two‐year period. The authors adopt the position that technology as well as humans has a moral character in order to disclose ethical concerns that are not transparent to users of the site.
Findings
Much research on the ethics of information systems has focused on the way that people deploy particular technologies, and the consequences arising, with a view to making policy recommendations and ethical interventions. By focusing on technology as a moral actor with reach across and beyond the internet, the authors reveal the complex and diffuse nature of ethical responsibility and the consequent implications for governance of SNS.
Research limitations/implications
The authors situate their research in a body of work known as disclosive ethics, and argue for an ongoing process of evaluating SNS to reveal their moral importance. Along with that of other authors in the genre, this work is largely descriptive, but the paper engages with prior research by Brey and Introna to highlight the scope for theory development.
Practical implications
Governance measures that require the developers of social networking sites to revise their designs fail to address the diffuse nature of ethical responsibility in this case. Such technologies need to be opened up to scrutiny on a regular basis to increase public awareness of the issues and thereby disclose concerns to a wider audience. The authors suggest that there is value in studying the development and use of these technologies in their infancy, or if established, in the experiences of novice users. Furthermore, flash points in technological trajectories can prove useful sites of investigation.
Originality/value
Existing research on social networking sites either fails to address ethical concerns head on or adopts a tool view of the technologies so that the focus is on the ethical behaviour of users. The authors focus upon the agency, and hence the moral character, of technology to show both the possibilities for, and limitations of, ethical interventions in such cases.
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