1,441 research outputs found

    Isospin effects on the energy of vanishing flow in heavy-ion collisions

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    Using the isospin-dependent quantum molecular dynamics model we study the isospin effects on the disappearance of flow for the reactions of 58Ni^{58}Ni + 58Ni^{58}Ni and 58Fe^{58}Fe +58Fe^{58}Fe as a function of impact parameter. We found good agreement between our calculations and experimentally measured energy of vanishing flow at all colliding geometries. Our calculations reproduce the experimental data within 5%(10%) at central (peripheral) geometries

    Energy efficient global optimisation of reactive dividing wall distillation column

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    This is the author accepted manuscript. The final version is avialable from Taylor & Francis via the DOI in this recordAn optimisation problem to minimise energy requirements in the synthesis of bio-additive ethyl tertiary butyl ether (ETBE) via reactive dividing wall distillation column (RDWC) is considered. The contribution of the article is to solve a real-world optimisation problem by addressing two challenges: (i) finding optimal process conditions in few numbers of simulations and (ii) handling mixed-integer variables. An efficient global optimisation algorithm is used to find optimal process conditions and adapted to handle both integer and continuous variables. ETBE is produced by the reaction of ethanol and isobutene in RDWC and has proven its niche in reducing the energy requirements for reaction–separation processes. However, the overall economics of the process is governed by the energy requirements. Therefore, it is crucial to find the optimal process conditions for achieving a cost-effective process. Reboiler duty of RDWC, considered as a measure of the energy requirements to be minimised by using the algorithm. Seven variables (four integers and three continuous) are used in the optimisation process to minimise the reboiler duty. A very low value of reboiler duty is obtained after doing the optimisation, which not only provides insight when using RDWC but also shows the potential of the algorithm used.Natural Environment Research Council (NERC

    Subsidence Movements and Structural Damage Related to an Abandoned Coal Mine

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    An area in southwestern Illinois has been experiencing surface and subsurface movements with associated damage to surface structures. The area is underlain by an abandoned, partially extracted room-and-pillar underground coal mine. Instrumentation included TDR (Time Domain Reflectometry), Inclinometers, Sondex, Tiltplates, and precision land surveys. This paper presents the results of a 16-month cooperative study between the Department of Mining Engineering at SIUC and a local coal company

    A survey on handling computationally expensive multiobjective optimization problems with evolutionary algorithms

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    This is the author accepted manuscript. The final version is available from Springer Verlag via the DOI in this record.Evolutionary algorithms are widely used for solving multiobjective optimization problems but are often criticized because of a large number of function evaluations needed. Approximations, especially function approximations, also referred to as surrogates or metamodels are commonly used in the literature to reduce the computation time. This paper presents a survey of 45 different recent algorithms proposed in the literature between 2008 and 2016 to handle computationally expensive multiobjective optimization problems. Several algorithms are discussed based on what kind of an approximation such as problem, function or fitness approximation they use. Most emphasis is given to function approximation-based algorithms. We also compare these algorithms based on different criteria such as metamodeling technique and evolutionary algorithm used, type and dimensions of the problem solved, handling constraints, training time and the type of evolution control. Furthermore, we identify and discuss some promising elements and major issues among algorithms in the literature related to using an approximation and numerical settings used. In addition, we discuss selecting an algorithm to solve a given computationally expensive multiobjective optimization problem based on the dimensions in both objective and decision spaces and the computation budget available.The research of Tinkle Chugh was funded by the COMAS Doctoral Program (at the University of Jyväskylä) and FiDiPro Project DeCoMo (funded by Tekes, the Finnish Funding Agency for Innovation), and the research of Dr. Karthik Sindhya was funded by SIMPRO project funded by Tekes as well as DeCoMo

    Gender and the right to mobility in South Asia

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    "South Asia including Bangladesh, India, Nepal, Pakistan and Sri Lanka encompasses source, transit and destination areas for women who migrate for employment. In context of current migration patterns, this study identifies and analyzes sociopolitical restrictions on women s mobility; and highlights local, national and regional feminist perspectives, strategies and approaches to promote mobility, work and freedom from violence at all stages of migration. The strategies and tactics discussed in this report expand current discourses on migrant rights and provide insight that can inform local, national and regional policies and programmes to promote migrant rights. Part I provides a brief overview of migration patterns, delineates the many restrictions on women s mobility and underlines the spectrums of violence faced by migrant women. Violence in this context includes economic, physical and sexual violence. Part II documents the range of strategies used by South Asia Women s Fund (SAWF) partners. These social movement actors are committed to addressing all forms of migration related violence through an explicitly feminist, rights-based and regional approach. Key thematic areas of engagement include confronting defacto and dejure restrictions on women s right to mobility, right to work and right to information; and challenging social and policy practices that undermine and stigmatize women s work. Finally, the study concludes with thematic recommendations grounded in grassroots experience to inform partner strategies, SAWF funding priorities and future directions of rights-based anti-trafficking initiatives. These insights are relevant to recent global initiatives to address the impact of uneven economic growth within and among countries, including the United Nations Sustainable Development Agenda, Habitat III Urban Agenda and International Labour Organization deliberations on Decent work in global supply chains and Violence against women and men in the world of work.

    Rheumatoid Meningitis

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    An 80-year-old woman with rheumatoid arthritis had gait difficulties and frequent falls. MRI of the brain showed an extra-axial enhancing lesion overlying the right frontal–parietal cortex, that progressively extended to the contralateral side. This was accompanied by further decline in her functional status. We discuss the diagnostic and therapeutic approach of a pachy–leptomeningeal process in a rheumatoid patient

    Comparison of distal radial access versus standard transradial access in patients with smaller diameter radial Arteries(The distal radial versus transradial access in small transradial ArteriesStudy: D.A.T.A - S.T.A.R study).

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    AIMS: To evaluate safety and efficacy of distal right radial access (DRRA) compared to right radial access (RRA), for coronary procedures, in patients with smaller diameter radial arteries (SDRA) (radial artery diameter (RAD) < 2.1 mm). METHODS AND RESULTS: This is a retrospective analysis of safety and efficacy of DRRA Vs. RRA in patients undergoing coronary procedures at our cardiac catheterization laboratories over a 10- month period between September 2017 and June, 2018 (first 5 calendar months with RRA-first; next 5 calendar months with DRRA-first). All patients underwent pre-procedure ultrasound of arm arteries. All patients had RAD<2.1 mm (mean RAD 1.63 ± 0.27 mm; RAD≤1.6 mm in 73.5%). Baseline characteristics were similar between groups. Primary end-point of puncture success was significantly lower in DRRA vs RRA group [79.5% vs 98.5%, p < 0.0001]. Puncture success was also lower in the subgroup of patients with RAD <1.6 mm Vs. ≥ 1.6 mm in the DRRA group (p < 0.0001). The secondary end-point of puncture time was significantly higher (2.1 ± 1.4 min vs. 1.0 ± 0.45 min, p < 0.00001) in the DRRA Vs. RRA group. The occurrence of vascular access site complications (including access site hematomas), radial artery occlusion (RAO) and distal RAO at day 1 and day 30 were similar between RRA and DRRA groups.Non-vascular access-site complication was seen only in the DRRA group. CONCLUSION: DRRA is a safe and effective access for coronary procedures; though technically challenging in patients with SDRA (RAD<2.1 mm; mean RAD 1.63 ± 0.27 mm), with lower puncture success and higher puncture time compared to RRA

    Artificial Intelligence Model Predicts Sudden Cardiac Arrest Manifesting With Pulseless Electric Activity Versus Ventricular Fibrillation

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    BACKGROUND: There is no specific treatment for sudden cardiac arrest (SCA) manifesting as pulseless electric activity (PEA) and survival rates are low; unlike ventricular fibrillation (VF), which is treatable by defibrillation. Development of novel treatments requires fundamental clinical studies, but access to the true initial rhythm has been a limiting factor. METHODS: Using demographics and detailed clinical variables, we trained and tested an AI model (extreme gradient boosting) to differentiate PEA-SCA versus VF-SCA in a novel setting that provided the true initial rhythm. A subgroup of SCAs are witnessed by emergency medical services personnel, and because the response time is zero, the true SCA initial rhythm is recorded. The internal cohort consisted of 421 emergency medical services-witnessed out-of-hospital SCAs with PEA or VF as the initial rhythm in the Portland, Oregon metropolitan area. External validation was performed in 220 emergency medical services-witnessed SCAs from Ventura, CA. RESULTS: In the internal cohort, the artificial intelligence model achieved an area under the receiver operating characteristic curve of 0.68 (95% CI, 0.61-0.76). Model performance was similar in the external cohort, achieving an area under the receiver operating characteristic curve of 0.72 (95% CI, 0.59-0.84). Anemia, older age, increased weight, and dyspnea as a warning symptom were the most important features of PEA-SCA; younger age, chest pain as a warning symptom and established coronary artery disease were important features associated with VF. CONCLUSIONS: The artificial intelligence model identified novel features of PEA-SCA, differentiated from VF-SCA and was successfully replicated in an external cohort. These findings enhance the mechanistic understanding of PEA-SCA with potential implications for developing novel management strategies

    Dependent types for JavaScript

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