1,693 research outputs found
Exposing the myth: object-relational impedance mismatch is a wicked problem
Addressing a problem of software integration is a fact of life for those involved in software development. The popularity of both object and relational technologies means that they will inevitably be used together. However, the combination of these two technologies introduces problems. These problems are referred to collectively as the object-relational impedance mismatch. A mismatch is addressed using one or more mapping strategies, typically embodied in a pattern. A strategy is concerned with correspondence between the schema of a relational database and an object-oriented program. Such strategies are employed in mapping tools such as Hibernate and TopLink, and reinforce the received wisdom that the problem of object-relational impedance mismatch has been solved. In this paper, we observe that it is not clear whether each strategy, as one possible solution, addresses the cause or a symptom of a mismatch. We argue that the problem is not tame and easily resolved; rather it is complex and wicked. We introduce a catalogue of problem themes that demonstrate the complex nature of the problem and provide a way both to talk about the problem and to understand its complexity. In the future, as software systems become more complex and more connected, it will be important to learn from past endeavours. Our catalogue of problem themes represents a shift, in thinking about the problem of object-relational impedance mismatch, from issues of implementation towards an analysis of cause and effect. Such a shift has implications for those involved in the design of current and future software architectures. Because we have questioned the received wisdom, we are now in a position to work toward an appropriate solution to the problem of object-relational impedance mismatch
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"It's only a computing project â so there canât be any ethical issuesâŚ"
For many years, BCS, the chartered institute for IT, has been requiring universities to demonstrate how they address Legal, Social, Ethical and Professional Issues (LSEPI) within programmes submitted for accreditation.
For equally many years, university departments have struggled to ensure that the 'dreaded LSEPIs' do appear somewhere. More recently, they have also needed to show how they are assessed â at least to some extent. But their integration into programmes still seems a little variable. In these days of burgeoning AI, deep mining of personal data (collected en masse, and sometimes without explicit permission), 'ethical' hacking, robotics and autonomous vehicles, do we need to reset the 'ethics' metric?
For example, can we be doing enough when claims of the form of the title still appear from time to time in student projects? The final year project is usually designed to be a synoptic capstone â so, if we really have covered LSEPIs, and specifically ethics, within a programme, then surely there should be a more considered reflection on ethics within the project report? And a considered reflection, not just a tick-box exercise such as seems to be adopted by many university ethics clearance committees...
In this talk, I shall aim to stimulate a discussion about just how pervasive ethics â and related LSEPIs â should be in our curricula, drawing on my experiences as an external examiner, a member of BCS accreditation panels, a BCS chartered membership assessor and â for more years than I care to remember â programme director for undergraduate computing at the Open University
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Workshop: The IoC Accrediation Standard
The Institute of Coding (IoC) offers an opportunity to do something radical. It is aimed at bridging the IT skills gap, increasing participation in computing course and making more graduates more employable.
The IoC brings together learning opportunities from HEIs, industry training and MOOCS. Learnersâ achievements will be recorded in a personal portfolio validated through blockchain
The IoC is developing a radical new accreditation standard for degrees, which is aimed directly at the reported needs of industry. The standard departs significantly from the normal approach of a focus on a Body of Knowledge (BoK), and seeks to extend the learning journey from knowing how to and demonstrating capability to the development of competence. Courses meeting the standard will aim to deliver âweek 1 billabilityâ for graduates, addressing directly long-standing concerns of (particularly) SMEs.
The purpose of this workshop was:
⢠to gain specific feedback on several aspects of proposed standard
⢠to gather employer opinions of standard
⢠to test feasibility of standard with respect to HEI delivery
The immediate feedback gathered during the workshop is embedded in the slidedeck, and has informed the subsequent evolution of the standard
Augmented Reality Smartphone Compasses: Opportunity or Oxymoron?
The development of augmented reality capabilities on smartphones has led to the emergence of a range of AR apps, including AR compasses. Some of these apps claim to be as good as professional magnetic navigation compasses, and suitable for navigation use. This poster presents detailed measurements of compass deviation (error) curves and offset errors for augmented reality compass apps on 17 mobile devices. The magnitude of the deviation errors measured casts serious doubt on claims the apps are appropriate for navigation purposes. This in turn emphasizes the need for the ubiquitous computing community to help ensure adequate awareness of the limitations of some onboard sensors, including compasses, on devices such as smartphones
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Including IT service management in the Computing curriculum: a caricature approach.
IT service management (itSM) is as important to the IT profession as is project management, which has long been recognised as an enabling skill for computing graduates. Both contribute to meeting accreditation criteria, and play into the employability agenda. itSM is prominent both in the SFIA framework and in the BCS Breadth of Knowledge test for CITP. Yet, unlike project management, itSM is integrated into only a handful of undergraduate computing degree programmes.
The principal challenge arises from the pedagogies and expectations of certification schemes and training courses being fundamentally different from those of higher education. itSM training courses seek to help participants engage with and enhance an existing service oriented working environment. For HE, the objective is to develop a deep understanding of the value and fundamental importance of itSM within the broad context of computing, and on understanding the reasons and justifications for effective itSM. The pedagogy needs also to encourage students to understand the risks of ignoring itSM â as with the risks of ignoring project management or the principles of software engineering. We present some challenges and questions encountered during the Open Universityâs development of itSM distance learning material for undergraduate Computing students. In a distance learning environment, the distinctions in objectives and pedagogy between certification and higher education are exacerbated by the limited opportunities for face-to-face discussions. Furthermore, the student body is disparate: some work in the sector, some are school-leavers with no work experience, and others work in completely different sectors.
We present our solution to these challenges: a "caricatureâ" pedagogy that emphasises the intended outcomes and benefits of IT service management, rather than its nomenclature, based on the classic ITIL service lifecycle. Our experience, including student reaction, suggests that this approach could enable the wider adoption of itSM teaching in university computing courses
Towards a framework for multiparadigm multimethodologies in systems thinking and practice
Burrell and Morgan (2000) claimed that knowledge is paradigmatic, encompassing a distinct worldview and rationality governing research strategies and methods for which they identified four sociological paradigms to locate them based on âmetatheoretical assumptions about the nature of reality, knowledge, and human behaviorâ (Cunliffe, 2010). They regard the competing theories developed from different paradigms as incommensurableâthose working in one paradigm are not understood by those committed to another. Moreover, âthere can be no measure, outside of the paradigms, which can be used as a basis for comparing and adjudicating between the claims toknowledge of theories produced from within different paradigmsâ (Jackson, 2000).This new theory states that because the problem of paradigm incommensurability begins at the level of ontology the solution lies there as well. Rather than supporting just one or a few paradigms, a different type of ontology is needed to explain ontological variety. It is argued that we can only perceive reality as meaningful paradigmatically, just as in the metaphor of the blind men and the elephant (Saxe, ca. 1850) where each comes upon a different part of an elephant andgeneralises that the whole is like their one piece. Furthermore, they cannot understand what they have found by comparing experiences.Solving the incommensurability issue is the theoretical key needed to properly underpin pluralist approaches to systems theory, design and intervention. But to do so, this new ontology is placed so that it operates within a suitable and otherwise complete theoretical framework which does not circumscribe, subsume, or in any way alter existing approaches, paradigms and theoriesâit purpose is only to sanction their use in a pluralist systemic approach. Such a framework, calledPâS Multiparadigm Perspectivity is described in this thesis.Ten interviews with systemists were conducted with mixed results. The tests mistakenly assumed that systemists were generally aware of paradigms and incommensurabilityâinstead, an aversion to theory was discovered. Surprisingly, though, two methods to address the issue were also found in the data. One of the interviewees teaches theory through storytelling; another demonstrates methods first, to pique the learnerâs interest and evoke their questions. It was learned that the adoption of this theory depends upon an improved awareness of the concepts of critical systems paradigms within the systemist community
An Investigation of the Distribution and Behavior of the Dark Rover Ant, \u3ci\u3eBrachymyrmex patagonicus\u3c/i\u3e Mayr, in South Carolina
The dark rover ant, Brachymyrmex patagonicus Mayr, is a minute (~0.5 mm) dark brown or black formicine ant invasive from Argentina and Paraguay. In the southeastern United States, the dark rover ant is considered a nuisance pest, and is difficult to control. Recently, B. patagonicus has expanded its invasive range, especially in the southeastern United States. In South Carolina, this species has become more common in pest control accounts. Despite this, most of the biology and behavior of the dark rover ant remains unknown. The only official record of B. patagonicus in South Carolina is from 2010 in Horry County. Based on personal observation and complaints from pest control operators, it was apparent this species was present in other parts of the state, but its distribution was unknown. Each of the 45 remaining counties in South Carolina were surveyed to investigate the presence of the dark rover ant. Target areas were chosen in each county which received a high volume of traffic such as schools, hospitals, and government buildings, and were sampled. Brachymyrmex patagonicus was collected and positively identified in all counties of South Carolina, indicating its invasive range is state wide, and provided 45 new county records. A distribution map was developed using these data, which also includes the first official record in Horry County from 2010. Reports from pest control operators indicated that B. patagonicus became a secondary pest after suppression of the red imported fire ant, Solenopsis invicta Buren. A series of four samples were conducted at ten trees on Clemson University Main Campus to measure the changes in foraging activity of B. patagonicus after S. invicta suppression using pitfall traps, baits, and tree scans. One sample was conducted to establish a baseline for B. patagonicus foraging activity, then half of the trees were treated with AdvionÂŽ (Syngenta Crop Protection Inc., 410 S Swing Rd, Greensboro, NC) fire ant bait, while the other half were left untreated to serve as a control. Then three more samples were conducted to measure the change in dark rover ant foraging activity. There was no significant difference in the number of B. patagonicus captured in pitfall traps before and after S. invicta suppression, and there was no significant difference in the number of dark rover ants in pitfalls in the treated area versus the untreated area. Also dark rover ants were no more likely to dominate a bait after the suppression of S. invicta. Data from tree scans indicated that the most commonly found co-occurring species with B. patagonicus were the red imported fire ant (S. invicta), Argentine ant (Linepithema humile (Mayr)), black carpenter ant (Camponotus pennsylvanicus (De Geer)), and field ants (Formica sp.). It has been widely reported from field observations that despite the fact that B. patagonicus co-occurs with other highly invasive or ecologically dominant ant species, it is not met with the same aggression levels as other species. A series of trials were conducted in a laboratory setting to confirm and quantify these interactions observed in the field. Brachymyrmex patagonius was paired against S. invicta, L. humile and Dorymyrmex bureni (Trager) to observe their interactions. Solenopsis invicta was also paired against L. humile and D. bureni to serve as a positive control for aggression. Ants were collected in the field and allowed to acclimate before being transferred to an experimental arena where they were observed for a period of five minutes, and their interactions scored according to a previously established agonism scale. Data indicate that the combinations including B. patagonicus versus L. humile, S. invicta, and D. bureni had a mean aggression score that was statistically significantly lower than the combinations including S. invicta versus L. humileand D. bureni. The combinations including dark rover ants versus other ecologically dominant or invasive ants also yielded mean aggression scores that were not significantly different from one another; as did the combinations including S. invicta versus L. humile and D. bureni The data indicate that B. patagonicus is universally met with lower levels of aggression, corroborating field observations. The cause of this interaction remains unknown. Future research should focus on both size and chemical interactions as potential causes for this unique interaction
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