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Aspect-based sentiment analysis as fine-grained opinion mining
We show how the general fine-grained opinion mining concepts of opinion target and opinion expression are related to aspect-based sentiment analysis (ABSA) and discuss their benefits for resource creation over popular ABSA annotation schemes. Specifically, we first discuss why opinions modeled solely in terms of (entity, aspect) pairs inadequately captures the meaning of the sentiment originally expressed by authors and how opinion expressions and opinion targets can be used to avoid the loss of information. We then design a meaning-preserving annotation scheme and apply it to two popular ABSA datasets, the 2016 SemEval ABSA Restaurant and Laptop datasets. Finally, we discuss the importance of opinion expressions and opinion targets for next-generation ABSA systems. We make our datasets publicly available for download
A smart cache content update policy based on deep reinforcement learning
This paper proposes a DRL-based cache content update policy in the cache-enabled network to improve the cache hit ratio and reduce the average latency. In contrast to the existing policies, a more practical cache scenario is considered in this work, in which the content requests vary by both time and location. Considering the constraint of the limited cache capacity, the dynamic content update problem is modeled as a Markov decision process (MDP). Besides that, the deep Q-learning network (DQN) algorithm is utilised to solve the MDP problem. Specifically, the neural network is optimised to approximate the Q value where the training data are chosen from the experience replay memory. The DQN agent derives the optimal policy for the cache decision. Compared with the existing policies, the simulation results show that our proposed policy is 56%-64% improved in terms of the cache hit ratio and 56%-59% decreased in terms of the average latency
A numerical investigation into the impact of icing on the aerodynamic performance of aerofoils
Aircraft wings and wind turbine blades are often subjected to harsh and cold climatic conditions. Icing is often observed on wing and blade surfaces in these cold climatic conditions. Wind turbine blades, in particular, are severely impacted by ice accretion which greatly hampers their performance and energy generation efficiency. Ice-accretion patterns are observed to vary with changes in temperature. As the temperature changes, the thickness of the ice accretion, the shape and location of ice-accretion vary greatly. In this paper, three different ice accretion patterns and their impact on the aerofoil efficiency have been investigated using the SS
Gender differential impact of bereavement on health outcomes: evidence from the China Health and Retirement Longitudinal Study, 2011–2015
Background: Bereavement is the experience of an individual following the death of a person of significance to the individual, most often referring to the spouse. Increased morbidity, health care utilization, and mortality are known to be associated with bereavement. Given China’s growing population of older adults, there is a critical need to assess the health consequences of bereavement. Method: We use data from the China Health and Retirement Longitudinal Study to examine the impact of bereavement on mental health and quality of life among a sample of mid- and older-aged adults. We use propensity score matching to construct a matching sample and difference-in-differences method to estimate the impact of bereavement on mental health and self-assessed health. Results: We find bereavement is associated with increased depression symptoms among women (1.542 point or 0.229 standard deviations of Center for Epidemiologic Studies Depression (CES-D) 10 score) but not consistently for men over time. No statistically significant effect of bereavement on self-assessed health is found. Conclusions: Our results show a harmful impact of bereavement on mental health among older women in China and point to the need for a comprehensive policy on survivor benefits in China, particularly for rural older women
It's the product not the polymer: rethinking plastic pollution
Mismanaged plastic waste poses a complex threat to the environments that it contaminates, generating considerable concern from academia, industry, politicians, and the general public. This concern has driven global action that presents a unique opportunity for widespread environmental engagement beyond the immediate problem of the persistence of plastic in the environment. But for such an opportunity to be realized, it is vital that the realities of plastic waste are not misrepresented or exaggerated. Hotspots of plastic pollution, which are often international in their source, present complex environmental problems in certain parts of the world. Here we argue, however, that the current discourse on plastic waste overshadows greater threats to the environment and society at a global scale. Antiplastic sentiments have been exploited by politicians and industry, where reducing consumers' plastic footprints are often confused by the seldom-challenged veil of environmental consumerism, or “greenwashing.” Plastic is integral to much of modern day life, and regularly represents the greener facilitator of society's consumption. We conclude that it is the product, not the polymer that is driving the issue of plastic waste. Contemporary consumption and disposal practices are the root of much of the anthropogenic waste in the environment, plastic, or not. Effective environmental action to minimize plastic in the environment should be motivated by changes in consumption practices, policies, and product design, and should be informed by objective science and legislation. This article is categorized under:. Science of Water > Hydrological Processes. © 2020 The Authors. WIREs Water published by Wiley Periodicals LLC
Transition delay and drag reduction using biomimetically inspired surface waves
This paper explores the use of Two-Dimensional sinusoidal surface features to delay transition and/or reduce drag. The authors, in this paper demonstrated that the presence of low amplitude sinusoidal surface features might damp the disturbances in the laminar boundary layer, reduce wall shear stress and maintain laminar flow for longer than a conventional flat plate. The hypothesis of the paper is inspired by the simplification of the dermal denticle on the surface of the shark-skin. Simulations are carried out using the Transition SST model in FLUENT based on the evidences of the transition model being suitable for a wider variety of high curvature scenarios. The surface waves are simulated for different amplitudes and wavelengths and their impact on transition onset and drag reduction are quantified at different velocities. Results presented in this paper indicate that a transition delay of 10.8% and a drag reduction of 5.2% are achievable. Furthermore, this paper adds credence to the notion that biomimicry is a very promising avenue for future drag reducing methods
Assessing the transition of municipal solid waste management using combined material flow analysis and life cycle assessment
Faced with the challenges to deal with increasingly growing and ever diversified municipal solid waste (MSW), a series of waste directives have been published by European Commission to divert MSW from landfills to more sustainable management options. The presented study assessed the transition of MSW man-agement in Nottingham, UK, since the enforcement of the EU Landfill Directive using a tool of combined materials flow analysis (MFA) and life cycle assess-ment (LCA). The results show that the MSW management system in Nottingham changed from a relatively simple landfill & energy from waste (EfW) mode to a complex, multi-technology mode. Improvements in waste reduction, material re-cycling, energy recovery, and landfill prevention have been made. As a positive result, the global warming potential (GWP) of the MSW management system re-duced from 1,076.0 kg CO2–eq./t of MSW in 2001/02 to 211.3 kg CO2–eq./t of MSW in 2016/17. Based on the results of MFA and LCA, recommendations on separating food waste and textile at source and updating treatment technologies are made for future improvement
Multi - mechanism coalescence design and matrix expression of logic action sequences of the over-turn nursing robot Part II: Gesture-state in sets and matrix
As is expressed in Part I, Functions and coalescence design of the over-turn nursing robot, the performance and requirements have been put forward with systematic design of several mechanisms. Here, in order to control and function well the over-turn nursing robot, the three-dimensional and five-dimensional Euclidean space with the real number were adopted in terms of sets for gesture of the bedridden person and the corresponding state of the robot, respectively. The matrix method was employed to define and describe the gestures-robot performance and its transition path. The gesture-state sequence matrix not only accurately and clearly expressed the gesture series, state sequence and their corresponding relations, but also laid a theoretical and technical foundation for the path planning from the current gesture to the target one. The control and operation of 7 states and 5 gestures were done to realize the automation and intelligent over-turning safely, comfortably and conveniently
Health literacy and its effect on chronic disease prevention: evidence from China’s data
Background: Improving health literacy is an important public health goal in many countries. Although many studies have suggested that low health literacy has adverse effects on an individual’s health outcomes, confounding factors are often not accounted. This paper examines the interplay between health literacy and chronic disease prevention.
Methods: A population-based sample of 8194 participants aged 15–69 years old in Ningbo were used from China’s 2017 National Health Literacy Surveillance Data. We use multivariate regression analysis to disentangle the relationship between health literacy and chronic disease prevention.
Results: We find the association between health literacy and the occurrence of the first chronic condition is attenuated after we adjust the results for age and education. This might arise because having one or more chronic conditions is associated with better knowledge about chronic diseases, thus improve their health literacy. More importantly, we find health literacy is associated with a reduction in the likelihood of having a comorbid condition. However, this protective effect is only found among urban residents, suggesting health literacy might be a key factor explaining the rural-urban disparity in health outcomes.
Conclusion: Our findings highlight the important role of health literacy in preventing comorbidities instead of preventing the first chronic condition. Moreover, family support could help improve health literacy and result in beneficial effects on health
Livelihood and vulnerability in the wake of Typhoon Yolanda: lessons of community and resilience
Livelihood strategies that are crafted in ‘extra-ordinary’ post-disaster conditions should
also be able to function once some semblance of normalcy has resumed. This article aims
to show that the vulnerability experienced in relation to Typhoon Yolanda was, and continues to be, directly linked to inadequate livelihood assets and opportunities. We examine the
extent to which various livelihood strategies lessened vulnerability post-Typhoon Yolanda
and argue that creating conditions under which disaster survivors have the freedom to pursue sustainable livelihood is essential in order to foster resilience and reduce vulnerability against future disasters. We offer suggestions to improve future relief efforts, including
suggestions made by the survivors themselves. We caution against rehabilitation strategies
that knowingly or unknowingly, resurrect pre-disaster vulnerability. Strategies that foster
dependency, fail to appreciate local political or ecological conditions or undermine cooperation and cohesion in already vulnerable communities will be bound to fail. Some of the
livelihood strategies that we observed post-Typhoon Yolanda failed on some or all of these
points. It is important for future policy that these failings are addressed