Multi-Objective Reinforcement Learning (MORL) poses significant challenges, primarily due to the necessity of balancing conflicting objectives-a limitation that traditional single-objective approaches fail to address....
详细信息
Multi-Objective Reinforcement Learning (MORL) poses significant challenges, primarily due to the necessity of balancing conflicting objectives-a limitation that traditional single-objective approaches fail to address. This paper introduces Multi-Objective Evolutionary Reinforcement Learning (MO-ERL), the first adaptation of Evolutionary Reinforcement Learning (ERL) specifically designed to address the complexities of the multi-objective domain effectively. MO-ERL integrates policy gradient-based reinforcement learning (RL), which optimizes expected utility, with evolutionary algorithms (EAs) that maintain diversity across the Pareto front. This combination leverages RL's strength in exploitation and EAs' proficiency in exploration, enabling MO-ERL to effectively navigate the trade-offs inherent in multi-objective optimization problems. Evaluation on multi-objective continuous control tasks using the MuJoCo physics engine demonstrates that MO-ERL outperforms state-of-the-art baselines, achieving up to 62.71% higher hypervolume and 196.28% greater expected utility. These results validate MO-ERL's ability to balance solution diversity and optimality, setting a new benchmark for solving MORL tasks.
Despite significant advances in bioprinting technology, current hardware platforms lack the capability for process monitoring and quality control. This limitation hampers the translation of the technology into industr...
详细信息
Despite significant advances in bioprinting technology, current hardware platforms lack the capability for process monitoring and quality control. This limitation hampers the translation of the technology into industrial GMP-compliant manufacturing settings. As a key step towards a solution, we developed a novel bioprinting platform integrating a high-resolution camera for in-situ monitoring of extrusion outcomes during embedded bioprinting. Leveraging classical computer vision and image analysis techniques, we then created a custom software module for assessing print quality. This module enables quantitative comparison of printer outputs to input points of the computer-aided design model's 2D projections, measuring area and positional accuracy. To showcase the platform's capabilities, we then investigated compatibility with various bioinks, dyes, and support bath materials for both 2D and 3D print path trajectories. In addition, we performed a detailed study on how the rheological properties of granular support hydrogels impact print quality during embedded bioprinting, illustrating a practical application of the platform. Our results demonstrated that lower viscosity, faster thixotropy recovery, and smaller particle sizes significantly enhance print fidelity. This novel bioprinting platform, equipped with integrated process monitoring, holds great potential for establishing auditable and more reproducible biofabrication processes for industrial applications.
BackgroundBisphosphonate use is associated with atypical non-traumatic fractures, which are most commonly seen in the *** presentationWe report a 63-year-old postmenopausal woman who presented acutely with progressive...
详细信息
BackgroundBisphosphonate use is associated with atypical non-traumatic fractures, which are most commonly seen in the *** presentationWe report a 63-year-old postmenopausal woman who presented acutely with progressively worsening lumbar pain radiating to her left hip for 10 days. There was no antecedent trauma. On examination, the patient could not bear weight on her left leg due to the severity of the pain. Radiography and computed tomography of the pelvis demonstrated an iliac wing fracture which was treated conservatively. The patient had a significant past medical history of breast cancer and intense bisphosphonate use for several years which was discontinued 3 years previously. No discrete bone lesion was seen at the fracture site on computed tomography, and there was no evidence of metastatic disease elsewhere. A dual-energy X-ray absorptiometry scan showed the lowest bone mineral density T-score of - 1.2. A diagnosis of an atypical fracture related to long-term bisphosphonate therapy was *** the best of our knowledge, this is the first reported case of an isolated iliac wing fracture associated with long-term bisphosphonate therapy in the literature. Whilst the incidence of such fractures is exceedingly rare, it is an important differential in patients with atypical fractures on long-term bisphosphonates.
Internationally, the need to have service user involvement (the 'voice' of recovery journeys) as an established and significant feature on the landscape of professional development has been widely discussed in...
详细信息
Internationally, the need to have service user involvement (the 'voice' of recovery journeys) as an established and significant feature on the landscape of professional development has been widely discussed in the area of mental health nursing (MHN) education for over a decade. Service user involvement contributes to a different understanding, bringing 'new' ways of knowing in nursing education and potentially new ways of practicing within mental health services. The objective of this co-produced research was to investigate the current local 'state of play' of service user involvement in MHN student education in a regional university in the Republic of Ireland. This was not research 'on' participants as conventionally conceived, but rather research 'with' participants as co-researchers. Therefore, a group of people [i.e., 'experts by experience/service users' (n = 2), 'student nurses' (n = 2), 'nurse academics' (n = 2)], came together by agreement in recognition of a problem (service user engagement in education) to seek local knowledge and through 'creative dialogue' to identify potential improvements/developments. The key outcomes concentrated on the need for person-centred care to be more than a one-off lecture in a course, but to be central to MHN education and ongoing practice. The need for MHNs to be educated to grasp that the individual they work with is not 'an island', but is connected to a wider network of family, friends and potentially peer support workers, etc. is highlighted. To enhance MHN education going forward, there is a need for 'lived experience' to be a consistent element of education programmes. Achieving this will require stable working relationships with the establishment of career pathways for 'experts by experience' to develop skills and experience in education settings. The pace of culture change in MHN education is sporadic at best and downright slow at worst. However, a lot has been done, but there is more to do: 'We've come a long way,
Climate change is expected to alter climate extremes. This paper evaluates future changes in extreme precipitation events over the Caspian Sea, where the changes are noticeable due to its geographical location and rem...
详细信息
Climate change is expected to alter climate extremes. This paper evaluates future changes in extreme precipitation events over the Caspian Sea, where the changes are noticeable due to its geographical location and remoteness from the ocean. Using bias-corrected data from the Coupled Model Intercomparison Project Phase 6 and extreme value analysis, this study shows increased precipitation from 18.48 mm/month in 1980-2014 to 19.50-19.82 mm/month in 2015-2100, depending on the climate scenario. Additionally, extreme events in the future are projected to increase over the sea due to climatic changes, depicting the emergence of droughts/floods that could occur more frequently in the region.
In this paper we present collectively fixed point theory for lower semicontinuous maps. In addition we present coincidence results between KKM type maps and lower semicontinuous maps. Our arguments are based on the Sc...
详细信息
In this paper we present collectively fixed point theory for lower semicontinuous maps. In addition we present coincidence results between KKM type maps and lower semicontinuous maps. Our arguments are based on the Schauder-Tychonoff fixed point theorem and a fixed point result based on KKM self maps on an admissible convex set in a Hausdorff topological vector space. As an application we present a new (Nash) equilibrium result for economies.
The formation of shear shock waves in the brain has been proposed as one of the plausible explanations for deep intracranial injuries. In fact, such singular solutions emerge naturally in soft viscoelastic tissues und...
详细信息
The formation of shear shock waves in the brain has been proposed as one of the plausible explanations for deep intracranial injuries. In fact, such singular solutions emerge naturally in soft viscoelastic tissues under dynamic loading conditions. To improve our understanding of the mechanical processes at hand, the development of dedicated computational models is needed. The present study concerns three-dimensional numerical models of incompressible viscoelastic solids whose motion is analysed by means of shock-capturing finite volume methods. More specifically, we focus on the use of the artificial compressibility method, a technique that has been frequently employed in computational fluid dynamics. The material behaviour is deduced from the Fung-Simo quasi-linear viscoelasiticity (QLV) theory where the elastic response is of Yeoh type. We analyse the accuracy of the method and demonstrate its applicability for the study of nonlinear wave propagation in soft solids. The numerical results cover accuracy tests, shock formation and wave focusing.
Animal manure is considered to have great potential for phosphorus (P) recovery due to its high P content, while P recovery is limited by the transfer of P from the solid phase to the liquid phase. The conventional di...
详细信息
Animal manure is considered to have great potential for phosphorus (P) recovery due to its high P content, while P recovery is limited by the transfer of P from the solid phase to the liquid phase. The conventional dissolution process by adding chemical acid reagents is not economically feasible for animal manure. This study used food waste (FW) as a co-substrate for the anaerobic fermentation of pig manure (PM) to achieve the release of P. The operational parameters were optimized, and the mechanisms of acidification and P release were further studied. The results showed FW promoted lactic acid production and rapid acidification. As FW increased from 0 to 80%, the concentrations of lactic acid rose from 0.12 +/- 0.04 to 11.95 +/- 1.37 g/L, with pH decreasing from 7.55 to 4.43. The ratio with FW/PM = 1:2 was the optimal condition, which led to the highest soluble phosphate concentration (350.39 +/- 8.59 mg/L) in 72 h, with a TP release rate of 74.24 +/- 1.81%. Multiple regression analyses established key relationships to predict pH changes in the reactor.
暂无评论