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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.

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.

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.

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.

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.

The purpose of this paper is to report changes when a classroom-based makerspace moved from face-to-face to an online setting.

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.

The analysis revealed changes in the role of physical and code artifacts, in improvising teaching, and channels for communication between the teacher and students.

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.

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.

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.

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.

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.

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.

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.

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.

The paper uses an approach based on technological inscription and the commodification of difference to study Gaydar, a commercial social networking site.

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.

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.

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.

The purpose of this paper is to explore the claim that online communication technologies are detrimental to off‐line communication practices.

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.

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.

The key value of the paper lies in understanding this technology as an archive of human relationships.

Dynamic assessment in the educational setting has been shown to offer many benefits for students with speech and language disorders. This chapter highlights the benefits of dynamic assessment and describes the limitations of static assessments. Because dynamic assessment can be implemented in many ways, three scenarios have been designed to provide an overview of some of these variations. Scenario 1 includes a graduated prompt approach for assessing abilities in the production of speech sounds using a standardized dynamic assessment. Scenario 2 includes a graduated prompt approach for assessing the linguistic skills underlying spelling errors. Scenario 3 includes a test-teach-retest approach for determining the presence of language impairment in students who speak a nonmainstream dialect of English. Suggestions for goal setting and increasing dynamic assessment applications for students with speech and language disorders are presented.