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How does monetary loss empathy modulate generosity in economic sharing behavior? An ERPs study
Previous studies have shown that generosity is driven by empathy and that both generosity in economic sharing behavior and monetary loss empathy decay as the social distance increases. However, it is still unclear whether this decay in economic sharing generosity can be influenced by the decay in monetary loss empathy. In the current study, we carried out two experiments to investigate this issue to deepen our understanding of the relationship between monetary loss empathy and generosity in economic sharing behavior. Our results show that in the observation group (observers watch their friend, and a stranger plays a gambling game), a negative correlation between log-transformed k value (ln(k)) and the distinction of d-FRN (feedback-related negativity difference between gain and loss) between friends and strangers was observed. However, in the execution group (executors play a gambling game themselves and watch a stranger play the same gambling game), there was no significant correlation between ln(k) and the distinction of d-FRN between self and strangers. Current results indicate that the decayed generosity across different social distances in economic sharing behavior can be modulated by the decayed monetary loss empathy. The study adds weight to the relationship between decayed monetary loss empathy and decayed generosity in sharing economic behavior at the level of social distance and provides electrophysiological evidence
Blood pressure estimation with complexity features from electrocardiogram and photoplethysmogram signals
A novel method for the continual, cuff-less estimation of the systolic blood pressure (SBP) and diastolic blood pressure (DBP) values based on signal complexity analysis of the photoplethysmogram (PPG) and the electrocardiogram (ECG) is reported. The proposed framework estimates the blood pressure (BP) values obtained from signals generated from 14 volunteers subjected to a series of exercise routines. Herein, the physiological signals were first pre-processed, followed by the extraction of complexity features from both the PPG and ECG. Subsequently the complexity features were used in regression models (artificial neural network (ANN), support vector machine (SVM) and LASSO) to predict the BP. The performance of the approach was evaluated by calculating the mean absolute error and the standard deviation of the predicted results and compared with the recommendations made by the British Hypertension Society (BHS) and Association for the Advancement of Medical Instrumentation. Complexity features from the ECG and PPG were investigated independently, along with the combined dataset. It was observed that the complexity features obtained from the combination of ECG and PPG signals resulted to an improved estimation accuracy for the BP. The most accurate DBP result of 5.15 ± 6.46 mmHg was obtained from ANN model, and SVM generated the most accurate prediction for the SBP which was estimated as 7.33 ± 9.53 mmHg. Results for DBP fall within recommended performance of the BHS but SBP is outside the range. Although initial results are promising, further improvements are required before the potential of this approach is fully realised
An in-depth analysis of system-level techniques for Simultaneous Multi-threaded Processors in Clouds
To improve the overall system utilization, Simultaneous Multi-Threading (SMT) has become a norm in clouds. Usually, Hardware threads are viewed and deployed directly as physical cores for attempts to improve resource utilization and system throughput. However, context switches in virtualized systems might incur severe resource waste, which further led to significant performance degradation. Worse, virtualized systems suffer from performance variations since the rescheduled vCPU may affect other hardware threads on the same physical core. In this paper, we perform an in-depth experimental study about how existing system software techniques improves the utilization of SMT Processors in Clouds. Considering the default Linux hypervisor vanilla KVM as the baseline, we evaluated two update-to-date kernel patches IdlePoll and HaltPoll through the combination of 14 real-world workloads. Our results show that mitigating they could significantly mitigate the number of context switches, which further improves the overall system throughput and decreases its latency. Based on our findings, we summarize key lessons from the previous wisdom and then discuss promising directions to be explored in the future
Recovering lithium cobalt oxide, aluminium, and copper from spent lithium-ion battery via attrition scrubbing
In this manuscript, the results show that the single-stage liberation by using a cutting mill is sub-optimum. From the analysis, that the size fraction of 850 µm size fraction. The low recovery of LiCoO2 is caused by the particles that are still adhering on to the surface of the aluminium current collector. This lack of liberation prompted the use of attrition scrubbing as a secondary stage of mechanical treatment. 2.5 min Attrition scrubbing improves the selective liberation of cobalt towards aluminium and copper by 36.6 % and 42.6 % respectively. Attrition induces abrasion and it is shown to liberate the LiCoO2 particles. Results show a minimum of 80 wt% LiCoO2 particles can be recovered in the size fraction of < 38 µm with 7.0 wt% aluminium and 6.1 wt% copper recovery, making attrition scrubbing a suitable second stage mechanical treatment for the recovery of LiCoO2
Retraction: the “other face” of research collaboration?
The last two decades have witnessed the rising prevalence of both co-publishing and retraction. Focusing on research collaboration, this paper utilizes a unique dataset to investigate factors contributing to retraction probability and elapsed time between publication and retraction. Data analysis reveals that the majority of retracted papers are multi-authored and that repeat offenders are collaboration prone. Yet, all things being equal, collaboration, in and of itself, does not increase the likelihood of producing flawed or fraudulent research, at least in the form of retraction. That holds for all retractions and also retractions due to falsification, fabrication, and plagiarism (FFP). The research also finds that publications with authors from elite universities are less likely to be retracted, which is particularly true for retractions due to FFP. China stands out with the fastest retracting speed compared to other countries. Possible explanations, limitations, and policy implications are also discussed
Optimal critical mass for the two-dimensional Keller–Segel model with rotational flux terms
Our aim is to show that several important systems of partial differential equations arising in mathematical biology, fluid dynamics and electrokinetics can be approached within a single model, namely, a Keller-Segel-type system with rotational flux terms. In particular, we establish sharp conditions on the optimal critical mass for having global existence and finite time blow-up of solutions in two spatial dimensions. Our results imply that the rotated chemotactic response can delay or even avoid the blow-up. The key observation is that for any angle of rotation α∈(-π, π], the resulting PDE system preserves a dissipative energy structure. Inspired by this property, we also provide an alternative derivation of the general system via an energetic variational approach. ©2020 International Press
Drag reduction mechanism of Paramisgurnus dabryanus loach with self-lubricating and flexible micro-morphology
Underwater machinery withstands great resistance in the water, which can result in consumption of a large amount of power. Inspired by the character that loach could move quickly in mud, the drag reduction mechanism of Paramisgurnus dabryanus loach is discussed in this paper. Subjected to the compression and scraping of water and sediments, a loach could not only secrete a lubricating mucus film, but also importantly, retain its mucus well from losing rapidly through its surface micro structure. In addition, it has been found that flexible deformations can maximize the drag reduction rate. This self-adaptation characteristic can keep the drag reduction rate always at high level in wider range of speeds. Therefore, even though the part of surface of underwater machinery cannot secrete mucus, it should be designed by imitating the bionic micro-morphology to absorb and store fluid, and eventually form a self-lubrication film to reduce the resistance. In the present study, the Paramisgurnus dabryanus loach is taken as the bionic prototype to learn how to avoid or slow down the mucus loss through its body surface. This combination of the flexible and micro morphology method provides a potential reference for drag reduction of underwater machinery
Investigation of surface integrity in laser-assisted machining of nickel based superalloy
While laser-assisted machining can significantly improve the machinability of nickel-based superalloy, the mechanism of surface integrity evolution and its influence on the material functional performance is still not clear. The present study gives a comprehensive investigation on the surface integrity of laser-assisted milling (LAMill) process with an in-depth study of the mechanism of chip formation, microstructural and mechanical alternations, supported by key outcomes from the two constitutive processes, conventional milling (CMill) and single laser scanning (LS). Although the high thermal affected layer in LAMill process has been removed through the cutting chips, a significant bending effect has been found in both the LAMill and LS workpiece. More interestingly, a combined impact of the residual stress from LS and CMill has been found on LAMill workpiece while a lattice evolution has been revealed regarding both the thermal and mechanical influence. Specifically, inadequate fatigue performance on LAMill and LS workpiece has been found due to the high thermal effect in the superficial layer regarding the residual tensile stress distribution and microstructure variation. While LAMill is generally considered as a promising machining method with improved machinability of difficult-to-cut materials, this research shows a poor workpiece functional performance (fatigue) and justifies its application prospect
Solar-thermal conversion and steam generation: a review
Recently, steam generation systems based on solar-thermal conversion have received much interest, and this may be due to the widespread use of solar energy and water sources such as oceans and lakes. The photo-thermal desalination system becomes attractive as it can convert absorbed solar light energy into thermal energy and realise the desalination and water purification of saline water through the evaporation process. In this paper, the research status of solar-thermal conversion materials such as metal-based materials, semiconductor materials, carbon-base materials, organic polymer materials, composite photo-thermal materials and their solar-thermal conversion mechanism in recent years are reviewed. The physical process and evaluation principle of solar-thermal conversion are both carefully introduced. The methods of optimising thermal management and increasing the evaporation rate of a hybrid system are also introduced in detail. Four main applications of solar-thermal conversion technologies (seawater desalination, wastewater purification, sterilisation and power generation) are discussed. Finally, based on the above analysis, the prospects and challenges for future research in the field of desalination are discussed from an engineering and scientific viewpoint to promote the direction of research, in order to stimulate future development and accelerate commercial application
Ambiguity and its coping mechanisms in supply chains lessons from the Covid-19 pandemic and natural disasters
Purpose – The first purpose of this paper is to situate and conceptualise ambiguity in the operations management (OM) literature, as connected to supply chain decision-making (SCDM). The second purpose is to study the role of ambiguity-coping mechanisms in that context.
Design/methodology/approach – This research uses the behavioural decision theory (BDT) to better embed ambiguity in a generic SCDM framework. The framework explicates both behavioural and nonbehavioural antecedents of ambiguity and enables us to also ground the “coping” mechanisms as individual and organisational level strategies. Properties of the framework are illustrated through two “ambiguous” events – the 2011 Thai flood and Covid-19 pandemic.
Findings – Three key findings are documented. First, ambiguity is shown to distinctively affect supply chain decisions and having correspondence with specific coping mechanisms. Second, the conceptual framework shows how individual coping mechanisms can undermine rational-based organisational coping mechanisms, leading to “sub-optimal”(poor) supply chain decisions. Third, this study highlights the positive role of visibility but surprisingly organisational “experiential” learning is imperfect, due to the focus on “similar” past experience and what is known.
Originality/value – The paper is novel in two ways. First, it introduces ambiguity – an often neglected concept in operations management – into the supply chain lexicon, by developing a typology of ambiguity. Second, ambiguity-coping mechanisms are also introduced as both individual and organisational strategies. This enables the study to draw distinctive theoretical and practical implications