bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modeling and Dynamic Assignment of the Adaptive Buffer Spaces in Serial Production Lines
Authors: Huang Jing , Chang Qing , Arinez Jorge 
Published: September 2020

Abstract
In production systems, the buffer capacities have usually been assumed to be fixed during normal operations. Inspired by the observations from the real industrial operations, a novel concept of Adaptive Buffer Space (ABS) is proposed in this paper. The ABS is a type of equipment, such as movable racks or mobile robots with racks, which can be used to provide extra storage space for a production line to temporarily increase certain buffers’ capacities in a real-time fashion. A good strategy to assign and reassign the ABS can significantly improve real-time production throughput. In order to model the production systems with changing buffer capacities, a data-driven model is developed to incorporate the impact of buffer capacity variation in system dynamics. Based on the model, a real-time ABS assignment strategy is developed by analyzing real-time buffer levels and machine status. The strategy is demonstrated to be effective in improving the system throughput. An approximate dynamic programming algorithm, referred to as ABS-ADP, is developed to obtain the optimal ABS assignment policy based on the strategy. Traditional ADP algorithms often initialize the state values with zeros or random numbers. In this paper, a knowledge-guided value function initialization method is proposed in ABS-ADP algorithm to expedite the convergence, which saves up to 80% computation time in the case study.
Mechanical and Corrosion Assessment of Friction Self-Piercing Rivet Joint of Carbon Fiber-Reinforced Polymer and Magnesium Alloy AZ31B
Authors: Lim Yong Chae , Chen Jian , Jun Jiheon , Leonard Donovan N. , Brady Michael P. , Warren Charles David , Feng Zhili 
Published: September 2020

Abstract
In the present work, thermoset carbon fiber–reinforced polymer (CFRP) was spot joined to magnesium alloy AZ31B by a friction self-piercing riveting (F-SPR) process. Lap shear tensile and cross-tension testing were used to evaluate the mechanical joint performance. An average lap shear tensile load of 5.18 kN was achieved, while an average of 2.81 kN was found from cross-tension testing. All F-SPR samples showed a pullout of AZ31B after mechanical testing, indicating good mechanical interlocking between the steel rivet and AZ31B. Corrosion potential was measured for each material to establish the galvanic corrosion characteristics. As expected, AZ31B was found to be the most active, while thermoset CFRP was the most noble. The steel rivet fell between the AZ31B (active) and the thermoset CFRP (noble). Salt fog corrosion testing (ASTM B-117) was performed to evaluate the corrosion performance of the uncoated F-SPR joint. With up to 200 h of exposure, the post-corroded F-SPR joint integrity retained 81.2% of the pre-exposure F-SPR joint strength with AZ31B pullout failure mode. From cross-sectional analysis of the F-SPR joint, extensive corrosion of AZ31B was observed at the joint and other exposure areas. However, steel rivet was not significantly corroded due to sacrificial anode effect by which AZ31B corroded first in the galvanic couple.
Experimental Investigation of Lubrication Regimes of a Water-Lubricated Bearing in the Propulsion Train of a Marine Vessel
Authors: Avishai Dov , Morel Groper 
Published: September 2020

Abstract
Sliding bearings, operating in a full hydrodynamic lubrication regime, exhibit a low friction coefficient and extended life. In recent years, with the increase in environmental awareness and pollution prevention, attention is being directed to oil spills, which pollute the environment. This is extremely prominent in ships and submarines whose propeller shafts are typically supported by oil-lubricated sliding bearings. To reduce pollution risk and also to obtain a simpler and low-cost maintenance system, the propeller shafts of numerous modern marine vessels are supported by water-lubricated bearings. An experimental investigation into the lubrication regime of a water-lubricated bearing in the propulsion train of a naval vessel is presented. A test rig was designed and built to allow testing of a scaled water-lubricated composite bearing supporting a naval vessel propeller shaft. Experimental results quantifying the effect of the rotational speed on the operating eccentricity, the friction coefficient, and the bearing’s lubrication regimes are presented. The experimentally obtained results are compared with an elastohydrodynamic lubrication (EHL) model solved by employing comsol multiphysics modeling software, and the differences are addressed. Finally, conclusions that may assist in better understanding the operation profile of the bearing and thus improving the vessel’s operability are presented.
Optimal Design of Maxwell-Viscous Coulomb Air Damper With a Modified Fixed Point Theory
Authors: Wong Wai On , Wong Chun Nam 
Published: September 2020

Abstract
Air damper dynamic vibration absorber (DVA) is modeled using Maxwell transformed element and coulomb element. This damper serves to minimize vibration at resonant and operation of constant speed machine. Its stiffness and damping factor are transformed from Maxwell to Voigt arrangement. Meanwhile, viscous equivalent Coulomb damping is expressed by absolute relative motion. System transmissibility contours are plotted by min–max approach. Its optimal parameters are determined using this approach. Contour operation minimization is obtained from minimum system transmissibility. Moreover, exact solution of fixed points and optimal natural frequency ratio are obtained by a modified fixed point theory. Optimal design curve is derived by Coulomb damping derivative and maximum condition. Operational vibration level is minimized by 7% at the operation minimization using minimum condition. On the experimental side, test platform of the air damper is constructed using linear slide block system. Computational model of the air damper is established by its physical details and experimental data. Linear relationship is obtained between viscous and Coulomb damping angles. Modified fixed points are validated by frequency response function resonant peaks. Experimental vibration level is minimized by 5%, which being close to the minimization result. The model is validated within 5% accuracy by its optimal experimental curve.
Damping Mechanisms in Cable-Harnessed Structures for Space Applications: Experimental Validation
Authors: Agrawal Pranav , Salehian Armaghan 
Published: September 2020

Abstract
In this technical brief, the experimental study and model validations for the damping mechanisms of cable-harnessed beam structures are presented. The structure consists of cables wrapped around a host beam in a periodic zigzag pattern. A special case of cable attached along the beam length over its centerline is also considered. First, material damping in the cables is characterized using dynamic tests and the relevant cable damping factors are calculated for both the Kelvin–Voigt and hysteretic damping models. Experimental modal testing is then performed on the fabricated cable-harnessed beams to obtain the frequency response functions (FRFs). Finally, the experimental FRFs are compared with the damped analytical models. The test and model results are shown to be in very good agreements in predicting the structural damping induced by the cables.
A Floquet-Based Analysis of Parametric Excitation Through the Damping Coefficient
Authors: Afzali Fatemeh , Acar Gizem D. , Feeny Brian F. 
Published: September 2020

Abstract
The Floquet theory has been classically used to study the stability characteristics of linear dynamic systems with periodic coefficients and is commonly applied to Mathieu’s equation, which has parametric stiffness. The focus of this article is to study the response characteristics of a linear oscillator for which the damping coefficient varies periodically in time. The Floquet theory is used to determine the effects of mean plus cyclic damping on the Floquet multipliers. An approximate Floquet solution, which includes an exponential part and a periodic part that is represented by a truncated Fourier series, is then applied to the oscillator. Based on the periodic part, the harmonic balance method is used to obtain the Fourier coefficients and Floquet exponents, which are then used to generate the response to the initial conditions, the boundaries of instability, and the characteristics of the free response solution of the system. The coexistence phenomenon, in which the instability wedges disappear and the transition curves overlap, is recovered by this approach, and its features and robustness are examined.
Barriers to maternal health services during the Ebola outbreak in three West African countries: a literature review
Authors: Yerger Piper , Jalloh Mohamed , Coltart Cordelia E M , King Carina 
Published: September 2020

IntroductionThe Ebola virus disease (EVD) outbreak in West Africa, affecting Guinea, Liberia and Sierra Leone from 2014 to 2016, was a substantial public health crisis with health impacts extending past EVD itself. Access to maternal health services (MHS) was disrupted during the epidemic, with reductions in antenatal care, facility-based deliveries and postnatal care. We aimed to identify and describe barriers related to the uptake and provision of MHS during the 2014–2016 EVD outbreak in West Africa.MethodsIn June 2020, we conducted a scoping review of peer-reviewed publications and grey literature from relevant stakeholder organisations. Search terms were generated to identify literature that explained underlying access barriers to MHS. Published literature in scientific journals was first searched and extracted from PubMed and Web of Science databases for the period between 1 January 2014 and 27 June 2020. We hand-searched relevant stakeholder websites. A ‘snowball’ approach was used to identify relevant sources uncaptured in the systematic search. The identified literature was examined to synthesise themes using an existing framework.ResultsNineteen papers were included, with 26 barriers to MHS uptake and provision identified. Three themes emerged: (1) fear and mistrust, (2) health system and service constraints, and (3) poor communication. Our analysis of the literature indicates that fear, experienced by both service users and providers, was the most recurring barrier to MHS. Constrained health systems negatively impacted MHS on the supply side. Poor communication and inadequately coordinated training efforts disallowed competent provision of MHS.ConclusionsBarriers to accessing MHS during the EVD outbreak in West Africa were influenced by complex but inter-related factors at the individual, interpersonal, health system and international level. Future responses to EVD outbreaks need to address underlying reasons for fear and mistrust between patients and providers, and ensure MHS are adequately equipped both routinely and during crises.
Cross-sectional study of the association between cataract surgery and age-related macular degeneration in the era of phacoemulsification in the national health and nutrition examination survey 2005–2008
Authors: Zhu Zhuoting , Wang Wei , Liao Huan , Keel Stuart , Zhang Jian , He Mingguang 
Published: September 2020

ObjectiveTo determine the association between cataract surgery and age-related macular degeneration (AMD) in a representative US sample.DesignPopulation-based, cross-sectional study.SettingThe US National Health and Nutrition Examination Survey 2005–2008.ParticipantsA total of 5401 participants aged ≥40 years had information in cataract surgery status and gradable retinal photographs for right eyes.MethodsCataract surgery status was obtained from questionnaire. Non-mydriatic fundus photographs were collected and AMD status was assessed. The associations between AMD and cataract surgery were evaluated in right eyes using logistic regression models.ResultsOf 338 right eyes with any AMD, 107 right eyes (28.9%) had cataract surgery. After adjusting for multiple variables, there were significant associations between cataract surgery and any AMD (OR 1.36; 95% CI 1.03 to 1.81) or late AMD (OR 2.48; 95% CI 1.01 to 6.09). No significant association was found between cataract surgery and early AMD after adjusting for multiple covariates (OR 1.20; 95% CI 0.91 to 1.59).ConclusionOur results suggest that cataract surgery is associated with the presence of AMD, particularly for late AMD. Longitudinal studies investigating the risk and progression of AMD after cataract surgery are needed in the era of phacoemulsification.
Cryoablation for advanced non-small cell lung cancer: a protocol for a systematic review
Authors: Duan Hua , Zheng Shu-Yue , Luo Chufan , Fang Xueni , Wang Dan , Pang Haoyue , Wang Man , Chen Yu , Zhou Tian , Li Quanwang , Hu Kaiwen 
Published: September 2020

IntroductionNational Comprehensive Cancer Network has recommended cryoablation to replace the resection in the treatment of medically operable non-small cell lung cancer (NSCLC). Cryoablation also has been used for the advanced NSCLC in randomised controlled trials. However, they have not been systematically reviewed. Here, we provide a protocol to evaluate the effectiveness and safety of cryoablation in the treatment of advanced NSCLC.Methods and analysesWe will search PubMed, Embase, the Cochrane Library, Chinese Biomedical Database, China National Knowledge Infrastructure, Wanfang Database and Chinese Scientific Journal Database without language restrictions from inception until 1 February 2020. Trial registers (International Clinical Trials Registry platform, the US National Institutes of Health Ongoing Trials Register and the ISRCTN registry) and reference lists of retrieved articles will also be searched. Two reviewers will independently extract data on participants, interventions, comparisons, outcomes and assess the methodological quality by the Cochrane risk of bias tool. The strength of evidences will be evaluated according to the Grading of Recommendations Assessment, Development and Evaluation approach. Review Manager V.5.3 software will be used for data analyses. Meta-analyses will be performed if the data are sufficiently homogeneous. The primary outcomes will be objective response rate and overall survival. The secondary outcomes will be adverse effects, health-related quality of life, changes of immune indicators and surrogate outcomes (disease control rate, progression-free survival and survival rate).Ethics and disseminationEthics approval is not required, as this study will not involve patients. The results of this study will be submitted to a peer-reviewed journal for publication, to inform both clinical practice and further research.PROSPERO registration numberCRD42019138660.
My child’s legacy: a mixed methods study of bereaved parents and providers’ opinions about collaboration with NICU teams in quality improvement initiatives
Authors: Bourque Claude Julie , Dahan Sonia , Mantha Ginette , Reichherzer Martin , Janvier Annie 
Published: September 2020

ObjectiveAlthough stakeholders’ participation in healthcare is increasingly recommended, bereaved parents are often excluded for perceived potential risks to them. The objective of this study is to describe the ongoing involvement and the perspectives of bereaved parents engaged in different types of activities in Neonatal Intensive Care Units and providers who work with them.Design/methodsMixed methods convergent analysis.SettingCanadian paediatric tertiary care university hospital.ParticipantsAll bereaved members of the resource parents group (n=8) and most providers who work with them (n=16) answered a satisfaction/needs questionnaires.ResultsSince 2011, eight bereaved parents were involved in a large number of activities mostly related to palliative care (research, education or clinical care initiatives). Three engaged in peer-to-peer support activities while the others preferred activities outside of clinical units and/or without direct interactions with other families. All of them reported that their participation had positive impacts, but two parents also reported a reactivation of traumatic experiences during a medical simulation activity. All participants expressed a desire for further collaboration. Motivation to contribute gravitated around two central themes: helping others and helping themselves. Many wanted to give back, help other families, improve the system and meet with providers who had cared for their child. All stated that this kind of involvement empowered them and gave meaning to their experiences. Providers and researchers all reported positive experiences, mainly due to the unique perspectives of bereaved parents who took part in their projects.Conclusion(s)With careful recruitment and supervision, some bereaved parents can become resource parents involved in different types of activities. It is important to understand the positive impacts this type of engagement can have on their healing process and to control the risks related to their participation. Research is needed to develop pertinent tools and measures to evaluate the outcomes and impacts of their participation.
Prevalence of TB symptoms, diagnosis and treatment among people living with HIV (PLHIV) not on ART presenting at outpatient clinics in South Africa and Kenya: baseline results from a clinical trial
Authors: Brennan Alana , Maskew Mhairi , Larson Bruce A , Tsikhutsu Isaac , Bii Margaret , Vezi Lungisile , Fox Matthew , Venter Willem Daniel Francois , Ehrenkranz Peter D , Rosen Sydney 
Published: September 2020

ObjectiveWe used screening data and routine clinic records for intervention arm patients in the Simplified Algorithm for Treatment Eligibility (SLATE) trials to describe the prevalence of tuberculosis (TB) symptoms, diagnosis and treatment among people living with HIV (PLHIV), not on antiretroviral therapy (ART) and presenting at outpatient clinics in South Africa and Kenya. We compared the performance of the WHO four-symptom TB screening tool with a baseline Xpert test.SettingOutpatient HIV clinics in South Africa and Kenya.ParticipantsEligible patients were non-pregnant, PLHIV, >18 years of age, not on ART, willing to provide written informed consent. A total of 594 patients in South Africa and 240 in Kenya were eligible.ResultsPrevalence of any TB symptom was 38% in Kenya, 35% (SLATE I) and 47% (SLATE II) in South Africa. During SLATE I, 70% of patients in Kenya and 57% in South Africa with ≥1 TB symptom were tested for TB. In SLATE II, 79% of patients with ≥1 TB symptom were tested. Of those, 19% tested positive for TB in Kenya, 15% (SLATE I) and 5% (SLATE II) tested positive in South Africa. Of the 28 patients who tested positive in both trials, 20 initiated TB treatment. The lowest median CD4 counts were among those with active TB (Kenya 124 cells/mm3; South Africa 193 cells/mm3). When comparing the WHO four-symptom screening tool to the Xpert test (SLATE II), we found that increasing the number of symptoms required for a positive screen from one to three or four decreased sensitivity but increased the positive predictive value to >30%.Conclusions80% of patients assessed for ART initiation presented with ≥1 TB symptoms. Reconsideration of the ‘any symptom’ rule may be appropriate, with ART initiation among patients with fewer/milder symptoms commencing while TB test results are pending.Trial registration numberNCT02891135 and NCT03315013.
Medication-related experiences of patients with polypharmacy: a systematic review of qualitative studies
Authors: Eriksen Christian Ulrich , Kyriakidis Stavros , Christensen Line Due , Jacobsen Ramune , Laursen Jannie , Christensen Mikkel Bring , Frølich Anne 
Published: September 2020

BackgroundWe aimed to synthesise qualitative studies exploring medication-related experiences of polypharmacy among patients with multimorbidity.MethodsWe systematically searched PubMed, Embase and Cumulative Index to Nursing and Allied Health Literature in February 2020 for primary, peer-reviewed qualitative studies about multimorbid patients’ medication-related experiences with polypharmacy, defined as the use of four or more medications. Identified studies were appraised for methodological quality by applying the Critical Appraisal Skills Programme checklist for qualitative research, and data were extracted and synthesised by the meta-aggregation approach.ResultsWe included 13 qualitative studies, representing 499 patients with polypharmacy and a wide range of chronic conditions. Overall, most Critical Appraisal Skills Programme items were reported in the studies. We extracted 140 findings, synthesised these into 17 categories, and developed five interrelated syntheses: (1) patients with polypharmacy are a heterogeneous group in terms of needing and appraising medication information; (2) patients are aware of the importance of medication adherence, but it is difficult to achieve; (3) decision-making about medications is complex; (4) multiple relational factors affect communication between patients and physicians, and these factors can prevent patients from disclosing important information; and (5) polypharmacy affects patients’ lives and self-perception, and challenges with polypharmacy are not limited to practical issues of medication-taking.DiscussionPolypharmacy poses many challenges to patients, which have a negative impact on quality of life and adherence. Thus, when dealing with polypharmacy patients, it is crucial that healthcare professionals actively solicit individual patients’ perspectives on challenges related to polypharmacy. Based on the reported experiences, we recommend that healthcare professionals upscale communicative efforts and involve patients’ social network on an individualised basis to facilitate shared decision-making and treatment adherence in multimorbidpatients with polypharmacy.
Case for hospital nurse-to-patient ratio legislation in Queensland, Australia, hospitals: an observational study
Authors: McHugh Matthew D , Aiken Linda H , Windsor Carol , Douglas Clint , Yates Patsy 
Published: September 2020

ObjectivesTo determine whether there was variation in nurse staffing across hospitals in Queensland prior to implementation of nurse-to-patient ratio legislation targeting medical-surgical wards, and if so, the extent to which nurse staffing variation was associated with poor outcomes for patients and nurses.DesignAnalysis of cross-sectional data derived from nurse surveys linked with admitted patient outcomes data.SettingPublic hospitals in Queensland.Participants4372 medical-surgical nurses and 146 456 patients in 68 public hospitals.Main outcome measures30-day mortality, quality and safety indicators, nurse outcomes including emotional exhaustion and job dissatisfaction.ResultsMedical-surgical nurse-to-patient ratios before implementation of ratio legislation varied significantly across hospitals (mean 5.52 patients per nurse; SD=2.03). After accounting for patient characteristics and hospital size, each additional patient per nurse was associated with 12% higher odds of 30-day mortality (OR=1.12; 95% CI 1.01 to 1.26). Each additional patient per nurse was associated with poorer outcomes for nurses including 15% higher odds of emotional exhaustion (OR=1.15; 95% CI 1.07 to 1.23) and 14% higher odds of job dissatisfaction (OR=1.14; 95% CI 1.02 to 1.28), as well as higher odds of concerns about quality of care (OR=1.12; 95% CI 1.01 to 1.25) and patient safety (OR=1.32; 95% CI 1.11 to 1.57).ConclusionsBefore ratios were implemented, nurse staffing varied considerably across Queensland hospital medical-surgical wards and higher nurse workloads were associated with patient mortality, low quality of care, nurse emotional exhaustion and job dissatisfaction. The considerable variation across hospitals and the link with outcomes suggests that taking action to improve staffing levels was prudent.