Evaluation Of Workability Research Articles

Evaluation of Hot Workability of Nickel-Based Superalloy Using Activation Energy Map and Processing Maps.

The stress-strain curves for nickel-based superalloy were obtained from isothermal hot compression tests at a wide range of deformation temperatures and strain rates. The material constants and deformation activation energy of the investigated superalloy were calculated. The accuracy of the constitutive equation describing the hot deformation behavior of this material was confirmed by the correlation coefficient for the linear regression. The distribution of deformation activation energy Q as a function of strain rate and temperature for nickel-based superalloy was presented. The processing maps were generated upon the basis of Prasad stability criterion for true strains ranging from 0.2 to 1 at the deformation temperatures range of 900–1150 °C, and strain rates range of 0.01–100 s−1. Based on the flow stress curves analysis, deformation activation energy map, and processing maps for different true strains, the undesirable and potentially favorable hot deformation parameters were determined. The microstructural observations confirmed the above optimization results for the hot workability of the investigated superalloy. Besides, the numerical simulation and industrial forging tests were performed in order to verify the obtained results.

English

English

222 斜め加力レオメーターによる左官材料のワーカビリチー評価方法 その1 : 混入ポリマーと骨材の違いの影響

222 斜め加力レオメーターによる左官材料のワーカビリチー評価方法 その1 : 混入ポリマーと骨材の違いの影響

The Medical Benefits of Work and the Health “Cost” of Unemployment

Abstract In 2011, the American Medical Association published the AMA Guides to the Evaluation of Work Ability and Return to Work (AMA's Return to Work), Second Edition, which began with a review of consensus statements attesting that, in general, work is good for a person's health and well-being. Since publication of AMA's Return to Work, the Australian Royal College of Physicians has issued a consensus statement about the negative health consequences of becoming unemployed and the health benefits of returning to work. Key points include: for most individuals, working improves general health and well-being and reduces psychological distress; even musculoskeletal and mental health conditions attributed to work can benefit from activity-based rehabilitation and an early return to suitable work; long-term work absence is harmful to physical and mental health and well-being; the negative effects of remaining away from work include stress on the worker's families, including children. Of the potential consequences of unemployment in mid-adult life, the worst is premature death. In causation research, unlike medical treatment studies, individuals cannot be randomly assigned to a group that is forced to remain at work and a group that is forced to be unemployed. Even so, causation research has found strong evidence for a protective effect of employment on depression and general mental health. In performing evaluations, physicians must accurately assess work ability and recognize the healthy benefits of work.

Rise of the machines: will heart failure become the first cyber-specialty?

Digital healthcare is being introduced to the management of heart failure as a consequence of innovations in information technology. Advancement in technology enables remote symptom and device monitoring, and facilitates early detection and treatment of heart failure exacerbation, potentially improving patient outcomes and quality of life. It also provides the potential to redesign our heart failure healthcare system to one with greater efficacy through resource-sparing, computer-aided decision-making systems. Although promising, there is, as yet, insufficient evidence to support the widespread implementation of digital healthcare. Patient-related barriers include user characteristics and health status; privacy and security concerns; financial costs and lack of accessibility of digital resources. Physician-related barriers include the lack of infrastructure, incentive, knowledge and training. There are also a multitude of technical challenges in maintaining system efficiency and data quality. Furthermore, the lack of regulation and legislation regarding digital healthcare also prevents its large-scale deployment. Further education and support and a comprehensive workable evaluation framework are needed to facilitate confident and widespread use of digital healthcare in managing patients with heart failure.

Experimental analysis on rheological properties for control of concrete extrudability

In this study, we examined the relationship among the rheological properties, workability, and extrudability in the construction of concrete structures using additive manufacturing. We altered the component materials (binder type, water-binder (W/B) ratio, sand ratio) to assess their effect on the rheological properties experimentally. The results indicated that the W/B and sand ratios had the largest effect on the rheological properties. In particular, when the sand ratio increased, it indicated that adjusting the sand ratio would facilitate control over the rheological properties. Additionally, we compared the rheological properties with the results of a traditional workability evaluation, namely the table flow test. This indicated the possibility of inferring the rheological properties by using traditional methods. Finally, we evaluated extrusion quantity according to table flow. The extrusion rate was 350 g/s for a flow of 210 mm and 170 g/s for a flow of 130 mm, indicating that extrusion rate increased as flow increased; however, we concluded that a flow standard of approximately 140-160 mm is suitable for controlling the actual extrusion quantity and rate.

Correction: Evaluation of Workability and Mechanical Properties of Stone Matrix Asphalt Mixtures Made with and without Stabilizing Additives

Correction: Evaluation of Workability and Mechanical Properties of Stone Matrix Asphalt Mixtures Made with and without Stabilizing Additives

Evaluation of Workability and Mechanical Properties of Stone Matrix Asphalt Mixtures Made With and Without Stabilizing Additives

Stone matrix asphalt (SMA) is a gap-graded mixture which is the combination of higher concentration of coarse aggregate and binder mortar. The coarse aggregate skeleton provides the mixture with stone-on-stone contact, giving it strength, while the high binder content mortar adds durability. The mortar is typically composed of fine aggregate, mineral filler, binder, and a stabilizing additive. A stabilizing additive such as cellulose fibers, mineral fibers, or polymers is added to SMA mixtures to prevent draindown of the mastics. In addition, it has the potential of reinforcing and improving the tensile strength of SMA mixtures. This paper presents the findings of performance of SMA mixtures with and without stabilizing additive. Superpave mix design, draindown, fatigue, rutting, workability, and moisture-induced damage properties of the SMA mixtures was evaluated. Three types of stabilizing additives (B, S, and V), one nominal maximum aggregate size (NMAS) 13.0 mm, and an unmodified asphalt binder (VG-30) were used in the study. Results indicate that the addition of stabilizing additive controls binder draindown and mix design properties of SMA mixtures satisfies the IRC SP 79 requirements. Resistance to rutting, fatigue, and moisture-induced damage of SMA with stabilizing additives were higher than SMA mixture without stabilizing additive. Further, SMA mixture without stabilizing additive takes less energy for densification compared with SMA mixture with stabilizing additives.

Social validity for work ability assessments and official decisions – clients’ experiences

Abstract Background Professionals need to be able to express what is at stake during the decision-making process and the discrepancy between formal rules and practical rationality need to be bridgeable and transparent for outsiders. Investigations of social validity for work ability assessments are rare. However, the concept can provide valuable information upon the acceptability and comprehensibility of procedures and how professionals can increase clients’ participation. The purpose of this study was to investigate social validity for work ability evaluations within the sickness insurance system and the official decisions they lead to. Methods This was a longitudinal qualitative study using telephone interviews and files from the Swedish Social Insurance Agency. Clients (n = 30) were interviewed after their participation in a work ability evaluation as well as after receiving an official decision upon eligibility for sickness benefits. Data was analyzed using a deductive content analysis. Results Preliminary findings show that clients’ comprehensibility of the different tests and their composition were depending on whether the specific tests were perceived as clearly related to the clients’ difficulties and what information they had received. In order to receive a fair description of the client’s work ability, clients state that the work ability evaluation needs to be individually adapted and that the standardized structure is not relevant for all. What is acceptable and fair to one client could be unacceptable to another, depending on what arguments and information case-managers and evaluation professionals provided. Conclusions Authorities need to express and motivate the reasons for a diverse range of steps during clients sick-leave process, not only regarding official decisions. Social validity for work ability evaluations is depending on the provided information and the applicability to the clients’ situation. Key messages Social validity is depending on the provided information and the applicability to the clients’ situation. Authorities need to communicate clearly with clients through the whole sick-leave process.

RESEARCH OF HUMAN FATIGUE AND MEASUREMENT PARAMETERS FOR WORKABILITY ASSESSMENT

Human fatigue is reduced working capability for certain period of time as the result of unusual or prolonged workload. Fatigue arises when the body’s energy requirements exceed its supply. Fatigue first manifests as reduced concentration capability causing movement coordination and precision disruption leading to decreasing workability. Fatigue is an object of research in physiology, psychology, work ergonomics, medicine, and biotechnology where each domain has a focus on mental fatigue. The functional state in the context of professional activity is defined as a complex of characteristics of functions and qualities that determine the fulfilment of labour activity. Furthermore, a comprehensive estimation of subject functional state in combination with other factors like subject self-assessment and objective performance tests (cognitive load tests) is a necessary input for the evaluation of workability and efficiency on task. The heterogeneous nature of fatigue as a systemic manifestation requires analysis of multiple key parameters which are relevant to the specific type. The current feasibility study focuses on human biological signal from electrical activity of heart, brain, muscles and skin potentials as well as temperature, position, and respiration to obtain diagnostic parameters reflecting the state of cardiovascular, muscles, and central nervous systems for physiological monitoring of vital signs. The fatigue physiological parameter and feature formalization aim to support the development of a platform with complex passive multi-level fatigue monitoring system and workability evaluation system designed in order to provide an integrated service.

Communication characteristics between clients and stakeholders within the Swedish sickness insurance system – a document analysis of granted and withdrawn sickness benefit claims

Purpose: The purpose of this study was to investigate how communication within the Swedish sickness insurance system differs between cases of sick leave and how this may affect clients’ cases.Materials and methods: This was a document study using 30 client files from the Swedish Social Insurance Agency (SIA). The clients included had been on a work ability evaluation during their sick leave spell and were aged 32–64 years. The material was analyzed using qualitative document analysis.Results: The results show different approaches to communication, characterized by emotional argumentation, matter-of-fact driven argumentation and information exchange, which have diverse success in affecting official decisions. Arguments characterized by emotions such as frustration or desperation are to a larger extent neglected by the authorities compared to those characterized by a matter-of-fact driven approach and referring to regulations and medical certificates.Conclusion: There are differences regarding how clients and stakeholders communicate the clients’ needs and pre-requisites, and how this affects official decisions. Further research must be carried out in order to establish social insurance literacy, initially for individuals on sick leave within the sickness insurance system, and whether there are differences between diverse groups that could lead to injustices.Implications for rehabilitationWithin a social insurance context, professionals need to provide clients with adequate and individually adapted information in order for procedures to be perceived as comprehensible and manageable by the clients.The support from stakeholders such as the treating physician and/or employer can affect clients’ sick-leave process.Clients’ treating medical professionals can contribute to ensuring that clients rights are met by communicating the clients’ needs to other stakeholders in a formal way.

Fracture diagnostics and operational workability evaluation of working turbine blades of aircraft engine

Fracture diagnostics and operational workability evaluation of working turbine blades of aircraft engine

Going digital: a narrative overview of the effects, quality and utility of mobile apps in chronic disease self-management.

Objective Smartphone health applications (apps) are being increasingly used to assist patients in chronic disease self-management. The effects of such apps on patient outcomes are uncertain, as are design features that maximise usability and efficacy, and the best methods for evaluating app quality and utility. Methods In assessing efficacy, PubMed, Cochrane Library and EMBASE were searched for systematic reviews (and single studies if no systematic review was available) published between January 2007 and January 2018 using search terms (and synonyms) of 'smartphone' and 'mobile applications', and terms for each of 11 chronic diseases: asthma, chronic obstructive lung disease (COPD), diabetes, chronic pain, serious mental health disorders, alcohol and substance addiction, heart failure, ischaemic heart disease, cancer, cognitive impairment, chronic kidney disease (CKD). With regard to design features and evaluation methods, additional reviews were sought using search terms 'design', 'quality,' 'usability', 'functionality,' 'adherence', 'evaluation' and related synonyms. Results Of 13 reviews and six single studies assessing efficacy, consistent evidence of benefit was seen only with apps for diabetes, as measured by decreased glycosylated haemoglobin levels (HbA1c). Some, but not all, studies showed benefit in asthma, low back pain, alcohol addiction, heart failure, ischaemic heart disease and cancer. There was no evidence of benefit in COPD, cognitive impairment or CKD. In all studies, benefits were clinically marginal and none related to morbid events or hospitalisation. Twelve design features were identified as enhancing usability. An evaluation framework comprising 32 items was formulated. Conclusion Evidence of clinical benefit of most available apps is very limited. Design features that enhance usability and maximise efficacy were identified. A provisional 'first-pass' evaluation framework is proposed that can help decide which apps should be endorsed by government agencies following more detailed technical assessments and which could then be recommended with confidence by clinicians to their patients. What is known about the topic? Smartphone health apps have attracted considerable interest from patients and health managers as a means of promoting more effective self-management of chronic diseases, which leads to better health outcomes. However, most commercially available apps have never been evaluated for benefits or harms in clinical trials, and there are currently no agreed quality criteria, standards or regulations to ensure health apps are user-friendly, accurate in content, evidence based or efficacious. What does this paper add? This paper presents a comprehensive review of evidence relating to the efficacy, usability and evaluation of apps for 11 common diseases aimed at assisting patients in self-management. Consistent evidence of benefit was only seen for diabetes apps; there was absent or conflicting evidence of benefit for apps for the remaining 10 diseases. Benefits that were detected were of marginal clinical importance, with no reporting of hard clinical end-points, such as mortality or hospitalisations. Only a minority of studies explicitly reported using behaviour change theories to underpin the app intervention. Many apps lacked design features that the literature identified as enhancing usability and potential to confer benefit. Despite a plethora of published evaluation tools, there is no universal framework that covers all relevant clinical and technical attributes. An inclusive list of evaluation criteria is proposed that may overcome this shortcoming. What are the implications for practitioners? The number of smartphone apps will continue to grow, as will the appetite for patients and clinicians to use them in chronic disease self-management. However, the evidence to date of clinical benefit of most apps already available is very limited. Design features that enhance usability and clinical efficacy need to be considered. In making decisions about which apps should be endorsed by government agencies and recommended with confidence by clinicians to their patients, a comprehensive but workable evaluation framework needs to be used by bodies assuming the roles of setting and applying standards.

Estimating the permeability of linear infrastructures using recapture data

Barrier effects of Large-scale Transportation Infrastructures (LTIs) are among the main factors contributing to the fragmentation of habitats. The reduction of dispersal across LTIs can drive small, local populations to extinction. To understand how LTIs modify dispersal, efficient and workable evaluation methods are required. We developed a method based on Mark-Release-Recapture surveys to estimate barrier effects of LTIs that could be easily applied in various landscape contexts and on any mobile species. Our method uses dispersal kernels of animal movements to calculate an expected probability of crossing any particular linear feature. This probability is then compared to observed crossing events to estimate the barrier effect. We used simulations to test the reliability of our method and applied this framework on the butterfly Maniola jurtina in a landscape fragmented by a motorway and a railway. Simulations showed that our method was able to detect efficiently even weak barrier effects given that enough data are available. When sample size was reduced, our method was able to detect barrier effects only when the infrastructure width was small in comparison to the average movement capacity of organisms. In our case study, both infrastructures acted as significant barriers. The power of our method is to use MRR data which are more representative of population processes than telemetry monitoring and are not limited by time-lag involved in genetic studies. This framework is of particular interest for conservation studies in order to assess how individual movements are modified by linear infrastructures.

Constitutive Modelling and Hot Workability Analysis by Microstructure Examination of GH4169 Alloy

The relationships between hot deformation parameters and flow behaviour have attracted many researchers’ attention for the past few decades, whilst precise constitutive modelling of GH4169 remained a problem, which seriously affected the process and microstructure control of alloys. In this work, a modified Arrhenius type model was introduced to describe the flow stresses of various compression conditions. The model showed high precision in flow stress prediction. In order to facilitate workability evaluation for engineering applications, the hot processing maps were established at the strain of 0.4~0.6. The processing maps revealed an instability domain at 900~950 °C and 0.1~1 s−1, a high dissipation efficiency domain at 1060~1100 °C and 0.001~0.01 s−1, and a stable deformation domain for the rest of processing parameters. Microstructures of each domain were observed via optical microscope (OM) and electron backscattered diffraction (EBSD). The intriguing finding was that the microstructures morphology agreed well with the descriptions in “discontinuous mechanism”, and incompletely recrystallized microstructures were found in the instability domain. Fully recrystallized microstructures were found in the stable deformation domain, and grain coarsen in the high dissipation efficiency domain. Optimal hot working conditions were suggested based on the microstructure analysis. This investigation contributed to a comprehensive understanding of the workability of GH4169.

Evaluation of Workability and Mechanical Properties of Nonfoaming Warm Mix Asphalt Mixtures

AbstractLaboratory evaluation of mix design and mechanical properties of Warm Mix Asphalt (WMA) mixtures is necessary during the design process; consequently, the ability to quantify the compactability of WMA mixtures would be very helpful. This article presents the findings of an experimental study aimed at evaluation of the influence of mixing and compaction temperature on mix design and mechanical and workability properties of nonfoaming WMA mixtures. Asphalt mix design properties were evaluated by the Marshall method and the Superpave method. Mechanical properties such as rutting resistance were evaluated by a laboratory wheel tracking test using a Wheel Rut Tester (WRT), and the resistance to moisture-induced damage was evaluated by the Tensile Strength Ratio (TSR) approach. Workability properties were evaluated in terms of Superpave Gyratory Compactor (SGC) densification indexes using the Bahia and locking point methods. Test results indicate that WMA mixtures compacted using SGC at a lower compaction temperature of 110°C, which satisfied the Voids in Total Mixture (VTM) requirement. In order to ensure the Voids in Mineral aggregate (VMA) and Voids Filled with Asphalt (VFA) requirements of WMA mixtures, compaction temperature should be restricted to 120°C. Furthermore, WMA mixtures prepared at lower compaction temperatures exhibited higher resistance to rut deformation because of higher Traffic Densification Index (TDI) values. The energy needed to compact the WMA mixtures at lower compaction temperatures was lower due to lower Compaction Densification Index (CDI) values. WMA mixtures made with surface-saturated dry aggregates and compacted at 110°C marginally fulfilled the minimum TSR requirement because of significant reduction in the Indirect Tensile Strength (ITS) values of conditioned specimen.

Evaluation of Workability on the Microstructure and Mechanical Property of Modified 9Cr-2W Steel for Fuel Cladding by Cold Drawing Process and Intermediate Heat Treatment Condition

In this study, we evaluated the cold drawing workability of two kinds of modified 9Cr-2W steel containing different contents of boron and nitrogen depending on the temperature and time of normalizing and tempering treatments. Using ring compression tests at room temperature, the effect of intermediate heat treatment condition on workability was investigated. It was found that the prior austenite grain size can be changed by the austenite transformation and that the grain size increases with increasing temperature during normalizing heat treatment. Alloy B and Alloy N showed different patterns after normalizing heat treatment. Alloy N had higher stress than Alloy B, and the reduction in alloy N increased while the reduction in alloy B decreased. Alloy B showed a larger number of initially formed cracks and a larger average crack length than Alloy N. Crack length and number increased proportionally in Alloy B as the stress increased. Alloy B had lower crack resistance than Alloy N due to boron segregation.

Visual evaluation of the possibility of rational product orientation in layered building at additive technologies installation

The developed subsystem of visual evaluation of triangulation models is presented. It is included in the system of technological planning of complex products manufacturing by additive technologies. This computer system allows to evaluate workability of industrial product and analyse the effectiveness of its production using additive technologies. It is proposed to perform an analysis of triangulated model of a complex product by colour visualizing of its representation on triangulated model of sphere and setting the colour scale of the correspondence to investigated characteristic of faces. The condition for mapping onto the sphere is the determination of inclination angles of faces vectors of the triangulation product model in the spherical coordinate system into the values range of a certain triangular face of the sphere model. Examples of workability evaluation based on analysis of spherical reflected of the original 3D model of product are considered. The proposed approach can significantly increase information capacity level in design development and visually determine possibility of rational product orientation in working space of layer-by-layer installation.

Evaluation of workability and strength of green concrete using waste steel scrap

This project works on the study of workability and mechanical properties of concrete using waste steel scrap from the lathe industry. Lathe industries produce waste steel scrap from the lathe machines. In this study, an attempt is made to use this waste in concrete, as accumulation of waste steel scrap cause disposal problem. Tests like compressive test, split tensile test, NDT test (UPV test) were conducted to determine the impact of steel scrap in concrete. The percentages of steel scrap considered in the study were 0%, 0.5%, 1%, 1.5%, and 2% respectively by volume of concrete, 7 day, 28 days test were conducted to find out strength of steel scrap concrete. It is observed that split tensile strength of steel scrap concrete is increased slightly. Split tensile strength of Steel scrap concrete is found to be maximum with volume fraction of 2.0% steel scrap. The steel scrap gives good result in split tensile strength of concrete. From the study concluded that steel scrap can be used in concrete to reduce brittleness of concrete to some extent.

Understanding of Processing, Microstructure and Property Correlations during Spheroidizing Heat Treatment of 100Cr6 Steel

In the present study an investigation has been carried out for spheroidization of 100Cr6 bearing steel used in forging industry. Three different spheroidization processes were considered. The first one was the annealing of normalized steel under Ac1 temperature for a long time. The second one was the annealing of normalized steel above Ar1 temperature after heating between Ac1 and Acm for one hour. The third one was the annealing of hardened steel under Ac1 temperature for a long time. For evaluation of cold workability with different spheroidization annealing periods, the yield strength and percentage of reduction in area in uniaxial tension were recorded. The present results indicate that low alloyed carbon bearing steels can be easily processed to achieve unique microstructures and properties.