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The implementation of inbound open innovation at the firm level: A dynamic capability perspective
Get PDFA Comprehensive Review of Control Techniques for Compensating the Fault Current in Resonant Grounded Distribution Networks: From the Perspective of Mitigating Powerline Bushfires
Get PDFPowerline faults are responsible for major bushfires around the world where arcs provoked from ground faults are common causes for igniting such fires. The grounding techniques (mainly resonant grounding) used in distribution substations and arc suppression devices play a crucial role for compensating fault currents in order to extinguish arcs so that the likelihoods of powerline bushfires are significantly reduced. Though passive arc suppression devices (e.g. Petersen coils) are extensively used for compensating the reactive component of the fault current, the active component of this current is still large enough to ignite the fire in bushfire prone areas for which active arc suppression devices are recently used. These active arc suppression devices incorporate residual current compensation inverters and the full compensation of the fault current rely on the control scheme of these inverters. This paper comprehensively reviews different control schemes that are used for compensating the fault current in resonant grounded power distribution systems. The existing control schemes are discussed in terms of the model used during the controller design process, loop structures, control block diagrams, and performance analysis frameworks (i.e. the type of fault impedances). It is worth mentioning that faults on resonant grounded power distribution networks exhibit the characteristics of high impedance faults and it important to consider this aspect for performance analysis of the control scheme. This paper also covers a brief overview of different grounding techniques used for mitigating fault currents and finally, the challenges with the existing controllers are identified in terms of extinguishing powerline bushfires. The comprehensive review motivates and guides future research activities on developing more efficient fault compensation techniques
How are hospitals in England caring for women at risk of preterm birth in 2021? The influence of national guidance on preterm birth care in England: a national questionnaire
Get PDFBackground
National guidance (Saving Babies Lives Care Bundle Version 2 (SBLCBv2) Element 5) was published in 2019, with the aim to standardise preterm care in England. We plan to identify how many preterm birth surveillance clinics there are in England, and to define current national management in caring for women who are both asymptomatic and high-risk of preterm birth, and who arrive symptomatically in threatened preterm labour, to assist preterm management both nationally and internationally.
Methods
An online survey comprising of 27 questions was sent to all maternity units in England between February 2021 to July 2021.
Results
Data was obtained from 96 units. Quantitative analysis and free text analysis was then undertaken. We identified 78 preterm birth surveillance clinics in England, an increase from 30 preterm clinics in 2017. This is a staggering 160% increase in 4 years. SBLCBv2 has had a considerable impact in increasing preterm birth surveillance clinic services, with the majority (61%) of sites reporting that the NHS England publication influenced their unit in setting up their clinic. Variations exist at every step of the preterm pathway, such as deciding which risk factors warrant referral, distinguishing within particular risk factors, and offering screening tests and treatment options.
Conclusions
While variations in care still do persist, hospitals have done well to increase preterm surveillance clinics, under the difficult circumstances of the COVID pandemic and many without specific additional funding
Seasonal temperatures in West Antarctica during the Holocene
Get PDFThe recovery of long-term climate proxy records with seasonal resolution is rare because of natural smoothing processes, discontinuities and limitations in measurement resolution. Yet insolation forcing, a primary driver of multimillennial-scale climate change, acts through seasonal variations with direct impacts on seasonal climate1. Whether the sensitivity of seasonal climate to insolation matches theoretical predictions has not been assessed over long timescales. Here, we analyse a continuous record of water-isotope ratios from the West Antarctic Ice Sheet Divide ice core to reveal summer and winter temperature changes through the last 11,000 years. Summer temperatures in West Antarctica increased through the early-to-mid-Holocene, reached a peak 4,100 years ago and then decreased to the present. Climate model simulations show that these variations primarily reflect changes in maximum summer insolation, confirming the general connection between seasonal insolation and warming and demonstrating the importance of insolation intensity rather than seasonally integrated insolation or season duration2,3. Winter temperatures varied less overall, consistent with predictions from insolation forcing, but also fluctuated in the early Holocene, probably owing to changes in meridional heat transport. The magnitudes of summer and winter temperature changes constrain the lowering of the West Antarctic Ice Sheet surface since the early Holocene to less than 162 m and probably less than 58 m, consistent with geological constraints elsewhere in West Antarctica4-7
Investigating the Moral Challenges Experienced by UK Service Police Veterans
Get PDFPrevious research has explored the negative effects of exposure to potentially morally injurious events among armed forces veterans and active-duty military personnel generally. However, this current pilot research provides a unique contribution to the extant research literature by examining the specific moral challenges experienced by a potentially at-risk and under-researched sub-group of military personnel. Semi-structured interviews were conducted with 10 United Kingdom (UK) Service Police veterans to identify any moral challenges encountered during their military service and to investigate the experience of moral dissonance underlying these events. Using Interpretative Phenomenological Analysis (IPA), four main themes (with sub-themes) emerged from the data: (a) violation of a moral code, (b) experience of disillusionment, (c) attempted resolution of moral dissonance, and (d) risk and protective factors for moral dissonance. Evidence of the types of moral challenges encountered by Service Police veterans during their military service and the negative consequences of moral dissonance was explored for the first time. Some of these findings overlap with existing evidence from non-Service Police research, although novel insights were also identified, such as the attempts of Service Police veterans to resolve moral dissonance through acting with moral courage, self-preservation, or seeking acceptance. The current research therefore provides a rationale for further investigation into the experience of moral dissonance and impact of exposure to morally injurious events in this sub-population of veterans. Potential implications for advancing conceptual understanding of moral injury and informing interventions to prevent the development of morally injurious outcomes are discussed
Exploring the effects of dopamine on sensorimotor inhibition and mobility in older adults
Get PDFDopaminergic activity decreases in older adults (OAs) with normal aging and is further reduced in Parkinson’s disease (PD), affecting cortical motor and sensorimotor pathways. Levodopa is the prevailing therapy to counter dopamine loss in PD, though not all PD motor signs improve with levodopa. The purpose of this preliminary study was to explore the effects of levodopa on sensorimotor inhibition, gait and quiet standing in OAs and to investigate the relationships between sensorimotor inhibition and both gait and standing balance both OFF- and ON-levodopa. Fifteen OA males completed a gait, balance and sensorimotor assessments before and 1 h after they were given a 100 mg dose of levodopa. Short-latency afferent inhibition quantified sensorimotor inhibition. Wearable sensors characterized gait (two-minute walk) and standing balance (1-min stance). No sensorimotor inhibition, gait, or standing balance measures changed from OFF- to ON-levodopa. When OFF-levodopa, worse inhibition significantly related to increased double stance (r = 0.62; p = 0.01), increased jerkiness of sway (r = 0.57; p = 0.03) and sway area (r = 0.58; p = 0.02). While ON-levodopa, worse inhibition related to increased arm swing range of motion (r = 0.63; p = 0.01) and jerkiness of sway (r = 0.53; p = 0.04). The relationship between SAI and arm swing excursion significantly changed from OFF- to ON-levodopa (z = − 3.05; p = 0.002; 95% confidence interval = − 0.95, − 0.21). Sensorimotor inhibition relationships to both gait and balance may be affected by dopamine in OAs. Cortical restructuring due to the loss of dopamine may be responsible for the heterogeneity of levodopa effect in people with PD and OAs
MetaDamage tool: Examining post-mortem damage in sedaDNA on a metagenomic scale
Get PDFThe use of metagenomic datasets to support ancient sedimentary DNA (sedaDNA) for paleoecological reconstruction has been demonstrated to be a powerful tool to understand multi-organism responses to climatic shifts and events. Authentication remains integral to the ancient DNA discipline, and this extends to sedaDNA analysis. Furthermore, distinguishing authentic sedaDNA from contamination or modern material also allows for a better understanding of broader questions in sedaDNA research, such as formation processes, source and catchment, and post-depositional processes. Existing tools for the detection of damage signals are designed for single-taxon input, require a priori organism specification, and require a significant number of input sequences to establish a signal. It is therefore often difficult to identify an established cytosine deamination rate consistent with ancient DNA across a sediment sample. In this study, we present MetaDamage, a tool that examines cytosine deamination on a metagenomic (all organisms) scale for multiple previously undetermined taxa and can produce a damage profile based on a few hundred reads. We outline the development and testing of the MetaDamage tool using both authentic sedaDNA sequences and simulated data to demonstrate the resolution in which MetaDamage can identify deamination levels consistent with the presence of ancient DNA. The MetaDamage tool offers a method for the initial assessment of the presence of sedaDNA and a better understanding of key questions of preservation for paleoecological reconstruction
Robust Multi-Objective Optimization for the Iranian Electricity Market Considering Green Hydrogen and Analyzing the Performance of Different Demand Response Programs
Get PDFUsing renewable energy sources (RES) and green hydrogen has increased dramatically as one of the best solutions to global environmental issues. Applying demand response programs (DRPs) in this context could enhance the system’s efficiency. Evaluating different DRPs’ performances and assessing economic impacts on different parts of the electricity market is essential. The inherent uncertainty of RES and prices is inevitable in electricity markets. As a result of the lack of information, it is crucial to mitigate the risks as much as possible, such as risks related to changes in demand, unit outages, or other traders’ bid strategies. This research introduces a robust multi-objective optimization method to reach the most confident plan for the retailer based on uncertainty in RES and price. The integration of different DRPs is assessed according to the cost to retailers and benefits for consumers using a multi-objective model to survey the impacts of different parts’ decisions on each other. The trade-off among DRPs is considered in this model, and they are traded using a new model to illustrate the daily effect of these programs in monthly operations. This paper uses hydrogen storage (HS) integrated with PV as a distributed energy resource. As the Iranian electricity market has just been established, this research proposes a framework for decision-making in new electricity markets to join future smart energy systems. The mid-term pricing evaluates the system’s performance for more accurate monthly results. Also, the operation cost of the hydrogen storage is modeled to assess its performance in non-robust and robust scheduling. Mixed-integer linear programming (MILP) has been used to model this problem in GAMS. A developed linearizing method is considered with a controllable amount of errors to reduce the volume and time of the computation. Finally, the cost of consumers in non-robust and robust market planning in the presence of DRPs is reduced by 8.77 % and 9.66 %, respectively, and HS has a compelling performance in peak-shaving and load-shifting
Proactive personality: A bibliographic review of research trends and publications
Get PDFProactive personality, as a personal initiative construct, enriches the growing body of literature in the field of business, management, and psychology. However, limited literature exists to synthesize the concept, and even no effort has been made to quantify and present the knowledge structure of proactive personality in the field. This study is a systematic review of 730 peer-reviewed articles from 62 journals in the Web of Science Core collection database between 1990 and 2020 in the field of business and economics. Using bibliometric analysis, 35,200 citations were used to highlight key contributions, citation networks, and fundamental research themes. Citation analysis presents the prolific scholars and main keywords that contribute to proactive personality research. Bibliographic coupling helps to classify thematic structure into five clusters: (i) entrepreneurship and corporate social responsibility, (ii) career development and performance, (iii) job crafting and work engagement, (iv) leadership and innovation, and (v) socialization and information seeking. These clusters received disproportionate attention in the past and may expect to gain popularity in the future trajectory of the topic
Efficient Sparse Representation for Learning With High-Dimensional Data
Get PDFDue to the capability of effectively learning intrinsic structures from high-dimensional data, techniques based on sparse representation have begun to display an impressive impact in several fields, such as image processing, computer vision and pattern recognition. Learning sparse representations is often computationally expensive due to the iterative computations needed to solve convex optimization problems in which the number of iterations is unknown before convergence. Moreover, most sparse representation algorithms focus only on determining the final sparse representation results and ignore the changes in the sparsity ratio during iterative computations. In this paper, two algorithms are proposed to learn sparse representations based on locality-constrained linear representation learning with probabilistic simplex constraints. Specifically, the first algorithm, called approximated local linear representation (ALLR), obtains a closed-form solution from individual locality-constrained sparse representations. The second algorithm, called approximated local linear representation with symmetric constraints (ALLRSC), further obtains all symmetric sparse representation results with a limited number of computations; notably, the sparsity and convergence of sparse representations can be guaranteed based on theoretical analysis. The steady decline in the sparsity ratio during iterative computations is a critical factor in practical applications. Experimental results based on public datasets demonstrate that the proposed algorithms perform better than several state-of-the-art algorithms for learning with high-dimensional data