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Why digital transformation may fail - and what can be done about it
Get PDFDigital transformations are as widespread as the chances of success are dismal. We highlight key reasons for failure and outline three strategies for change that can increase the chances of success. Organizations should help both business leaders and technology leaders understand and appreciate each other’s perspectives; and create shared ownership of the transformation. In-house technology DNA should be nurtured; shared targets should be developed; and constant efforts to integrate business and technology perspectives should be instituted
Mainstream and special schools’ use of well-being programmes : a regional survey
Get PDFThe incorporation of mental well-being provision into school curricula is increasingly the focus of government policy in the UK and internationally. However, it is not clear what well- being programmes schools provide to pupils, and how these programmes are delivered. The current study was an online survey to assess the use of whole-school well-being programmes in primary schools in North Wales. Normalisation Process Theory (NPT) was utilised as a framework to assess normalisation of the well-being programmes. One-hundred and fifty-one schools in North Wales responded to the survey. The mean number of whole-school well- being programmes utilised by schools was 4.59, and nine of the ten most frequently used programmes had little or no associated evidence base. The well-being programmes were generally perceived as normalised (i.e., everyday practice) by respondents. Implications for future practice are discussed, including the need to support schools to identify and implement evidence-based mental well-being provision
Reachability verification-based reliability assessment for deep reinforcement learning controlled robotics and autonomous systems
Get PDFDeep Reinforcement Learning (DRL) has achieved impressive performance in robotics and autonomous systems (RAS). A key challenge to its deployment in real-life operations is the presence of spuriously unsafe DRL policies. Unexplored states may lead the agent to make wrong decisions that could result in hazards, especially in applications where DRL-trained end-to-end controllers govern the behaviour of RAS. This letter proposes a novel quantitative reliability assessment framework for DRL-controlled RAS, leveraging verification evidence generated from formal reliability analysis of neural networks. A two-level verification framework is introduced to check the safety property with respect to inaccurate observations that are due to, e.g., environmental noise and state changes. Reachability verification tools are leveraged locally to generate safety evidence of trajectories. In contrast, at the global level, we quantify the overall reliability as an aggregated metric of local safety evidence, corresponding to a set of distinct tasks and their occurrence probabilities. The effectiveness of the proposed verification framework is demonstrated and validated via experiments on real RAS
ODD-based query-time scenario mutation framework for autonomous driving scenario databases
Get PDFLarge-scale scenario databases have been set up containing hundreds of thousands of traffic scenarios for the verification and validation (V&V) of autonomous vehicles (AV). Scenarios in the database are often labelled with semantic Operational Design Domain (ODD) tags (e.g., WeatherRainy, RoadTypeHighway and ActorTypeTruck) to be queried via exact tag matching. Such a scenario database design has two major limitations, i.e. combinatorial scenario generation inevitably leads to many redundant scenarios, and each ODD query matches only a small number of scenarios in the database (0.2% in our case study), rendering most of the database wealth wasted. We propose a novel scenario database design and an ODD-based query-time scenario mutation framework to address the limitations. Our case study results show that the proposed framework has the potential to fully utilize all the database scenarios at query time while eliminating scenario redundancy in the database (in our case study, given the same ODD query, the number of final matched scenarios increased by 36 times, diversity increased by 99 times, and scenario database utilization rate increased from 0.2% to 36%)
Comparative study of the anti-corrosive properties of thiols induced superhydrophobic surfaces
No full textFluoroalkyl thiols and alkyl thiols are widely used as low surface energy reagents for the preparation of superhydrophobic surfaces and corrosion resistant surfaces. Although the corrosion resistance of thiol-induced superhydrophobic surfaces has been well addressed previously, few studies have devoted to revealing the difference of fluoroalkyl thiol and alkyl thiol modified surfaces towards anti-corrosion. In this work, two types of superhydrophobic surfaces were prepared by respectively coating self-assembled monolayers (SAMs) of 1 H,1 H,2 H,2 H-perfluorodecanethiol (PFDT) and 1-dodecanethiol (DDT) on femtosecond laser engineered copper substrates. The formation mechanism of the SAMs was explained by analyzing the surface chemical composition. The water contact angle of the PFDT and DDT modified surfaces were measured to be 157.7° and 154.6°, respectively. Electrochemical tests showed that both SAMs significantly reduced the corrosion current density (Icorr) and corrosion rate of the copper surfaces, while simultaneously increased the charge transfer resistance (Rct) value by an order of magnitude compared to the pristine copper surface. The surface with PFDT SAM had the smallest Icorr and its Rct value was about 1.5 times larger than that with the DDT SAM. These results confirmed that both the SAMs enhanced the anti-corrosion properties of the copper surfaces, and the PFDT SAM was proved to be more effective. Furthermore, the anti-corrosion durability of the PFDT and DDT modified surfaces were compared after exposing them to salt, acid, and alkali solutions for 12 h, and the results showed that the surfaces maintained to be hydrophobic and anti-corrosive, and the PFDT induced superhydrophobic surface indicated better durability. Our results demonstrated that thiols SAMs could significantly improve the anti-corrosion property of structured metal surfaces, and that fluoroalkyl thiol was more desired for long-term anti-corrosive applications in comparison with alkyl thiol
Kodaira dimensions of almost complex manifolds II
Get PDFThis is the second of a series of papers where we study the plurigen- era, the Kodaira dimension and the Iitaka dimension on compact almost complex manifolds. By using the pseudoholomorphic pluricanonical map, we define the second version of Kodaira dimension as well as Iitaka dimension on compact almost complex manifolds. We show that almost complex structures with the top Kodaira dimension are integrable. For compact almost complex 4-manifolds with Kodaira dimension one, we obtain elliptic fibration like structural descrip- tion. Some vanishing theorems in complex geometry are generalized to the almost complex setting. For tamed symplectic 4-manifolds, we show that the almost Kodaira dimension is bounded above by the symplectic Kodaira dimension, by using a probabilistic combinatorics style argument. The appendix also contains a few results including answering a question of the second author that there is a unique subvariety in ex- ceptional curve classes for irrational symplectic 4-manifolds, as well as extending Evans-Smith’s constraint on symplectic embeddings of certain rational homology balls by removing the assumption on the intersection form
Meritocracy or reputation? The role of rankings in the sorting of international students across universities
Get PDFUniversity rankings have gained prominence in tandem with the global race towards excellence and as part of the growing expectation of rational, scientific evaluation of performance across a range of institutional sectors and human activity. While their omnipresence is acknowledged, empirically we know less about whether and how rankings matter in higher education outcomes. Do university rankings, predicated on universalistic standards and shared metrics of quality, function meritocratically to level the impact of long-established reputations? We address this question by analysing the extent to which changes in the position of UK universities in ranking tables, beyond existing reputations, impact on their strategic goal of international student recruitment. We draw upon an ad hoc dataset merging aggregate (university) level indicators of ranking performance and reputation with indicators of other institutional characteristics and international student numbers. Our findings show that recruitment of international students is primarily determined by university reputation, socially mediated and sedimented over the long term, rather than universities’ yearly updated ranking positions. We conclude that while there is insufficient evidence that improving rankings changes universities’ international recruitment outcomes, they are nevertheless consequential for universities and students as strategic actors investing in rankings as purpose and identity
Marketization, regulation, and equality : towards an analytical framework for understanding the equality impact of public procurement
Get PDFWith the rise of the regulatory welfare state, public procurement gained increasing importance as a tool for the regulation of wages and working conditions and a lever for promoting equality. Yet, despite growing attention to and understanding of public procurement’s relation to equality, existing knowledge remains fragmented. An analytical framework that captures and systematizes the multifaceted interaction between public procurement and equality is still missing. Focusing on conditions of purchasing and obligations set as part of the procurement processes, this article explores the way in which public procurement processes generate equality impacts first through stipulations and practices which are not explicitly linked to equality but generate equality impacts, and second through proactive measures designed to foster equality. It argues that a holistic understanding of public procurement’s equality impact needs to take account of the individual combination of features
How cognitive selection affects language change
No full textWords compete for survival in each language. This research investigates the cognitive mechanisms underlying the rise and fall of English word forms using two complementary research paradigms: a serial reproduction experiment where a story is passed on along a diffusion chain and a quantitative linguistic analysis of historical corpora that spans the past two centuries. We found that the competition among word forms is closely associated with how humans use language: words that are acquired earlier in life, more concrete, and more arousing are more likely to survive. Our results suggest that micro-level patterns of language production may scale up to macro-level patterns of language change over generations of language speakers
Learning partner selection rules that sustain cooperation in social dilemmas with the option of opting out
Get PDFWe study populations of self-interested agents playing a 2-person repeated Prisoner’s Dilemma game, with each player having the option of opting out of the interaction and choosing to be randomly assigned to another partner instead. The partner selection component makes these games akin to random matching, where defection is known to take over the entire population. Results in the literature have shown that, when forcing agents to obey a set partner selection rule known as Out-for-Tat, where defectors are systematically being broken ties with, cooperation can be sustained in the long run. In this paper, we remove this assumption and study agents that learn both action- and partner-selection strategies. Through multiagent reinforcement learning, we show that cooperation can be sustained without forcing agents to play predetermined strategies. Our simulations show that agents are capable of learning in-game strategies by themselves, such as Tit-for-Tat. What is more, they are also able to simultaneously discover cooperation-sustaining partner selection rules, notably Out-for-Tat, as well as other new rules that make cooperation prevail