scholarly journals Experimental and Discrete Element Model Investigation of Limestone Aggregate Blending Process in Vertical Static and/or Conveyor Mixer for Application in the Concrete Mixture

Processes ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 1991
Author(s):  
Lato L. Pezo ◽  
Milada Pezo ◽  
Anja Terzić ◽  
Aca P. Jovanović ◽  
Biljana Lončar ◽  
...  
Keyword(s):  
Binary Mixture ◽  
Element Model ◽  
Discrete Element ◽  
Numerical Approach ◽  
Primary Objective ◽  
Fine Aggregate ◽  
Relative Standard ◽  
Aggregate Fractions ◽  
The Impact

The numerical model of the granular flow within an aggregate mixture, conducted in the vertical static and/or the conveyor blender, was explored using the discrete element method (DEM) approach. The blending quality of limestone fine aggregate fractions binary mixture for application in self-compacting concrete was studied. The potential of augmenting the conveyor mixer working efficiency by joining its operation to a Komax-type vertical static mixer, to increase the blending conduct was investigated. In addition the impact of the feed height on the flow field in the cone-shaped conveyor mixer was examined using the DEM simulation. Applying the numerical approach enabled a deeper insight into the quality of blending actions, while the relative standard deviation criteria ranked the uniformity of the mixture. The primary objective of this investigation was to examine the behavior of mixture for two types of blenders and to estimate the combined blending action of these two mixers, to explore the potential to augment the homogeneity of the aggregate fractions binary mixture, i.e., mixing quality, reduce the blending time and to abbreviate the energy-consuming.

Quality of Life of Family Caregivers of Patients With Cancer in Korçe, Albania

2018 ◽  
Vol 34 (2) ◽  
pp. 118-125 ◽  
Author(s):  
Jonathon Judkins ◽  
Irena Laska ◽  
Judith Paice ◽  
Priya Kumthekar
Keyword(s):  
Quality Of Life ◽  
Well Being ◽  
Risk Groups ◽  
The United States ◽  
Primary Objective ◽  
Care Clinic ◽  
Demographic Groups ◽  
Spiritual Well Being ◽  
The Impact

Purpose: The primary objective of this study was to quantify cancer family caregiver (FCG) quality of life (QOL) in a Southern Albanian population and to determine whether differences exist between 4 domains of QOL (physical, psychological, social, and spiritual). This study also sought to compare QOL in our cohort to QOL in historical studies that used the same survey instrument, and to examine correlations between demographic characteristics and QOL to identify any high-risk groups. Methods: A sample of 40 FCGs was recruited at the Mary Potter Palliative Care Clinic in Korçe, Albania. Each participant completed the City of Hope Quality of Life (Family Version), a validated 37-question instrument that measures caregiver well-being in 4 domains: physical, psychological, social, and spiritual well-being. Results: There were no significant differences between the composite scores of the 4 QOL domains in our study. However, there were differences when comparing self-reported QOL between domains (“Rate your overall physical/psychological/social/spiritual well-being”). The QOL measured in our study was significantly lower than in 3 studies from the United States that used the same questionnaire. There were no significant correlations between demographic groups and QOL. Conclusions: This study examines the impact that the paucity of palliative services has on the QOL of Albanian cancer FCGs. Although there were no domains of QOL or demographic groups identified in our study that were faring significantly worse than others, the poor overall QOL provides further evidence to support the continued development of palliative services for both patients and family members in Albania.

Coupled Discrete Element/Finite Element Method for the Analysis of Large Reinforced Concrete Structures Submitted to an Impact

2011 ◽  
Vol 82 ◽  
pp. 284-289
Author(s):  
Laurent Daudeville ◽  
Jessica Haelewyn ◽  
Philippe Marin ◽  
Serguei Potapov
Keyword(s):  
Reinforced Concrete ◽  
Finite Elements ◽  
Heterogeneous Media ◽  
Concrete Slab ◽  
Element Model ◽  
Discrete Element ◽  
Discrete Elements ◽  
Reinforced Concrete Slab ◽  
The Impact ◽  
Element Method

The efficiency of the discrete element method for studying the fracture of heterogeneous media has been demonstrated, but it is limited by the size of the computational model. A coupling between the discrete elements (DEM) and the finite elements (FEM) methods is proposed to handle the simulation of impacts on large structures. The structure is split into two subdomains in each of which the method is adapted to the behavior of the structure under impact. The DEM takes naturally into account the discontinuities and is used to model the media in the impact zone. The remaining structure is modeled by the FEM. We propose an adaptation of the coupling procedure to connect Discrete Element model to shell-type Finite Elements. Finally, the efficiency of this approach is shown on the simulation of a reinforced concrete slab impacted by a tubular impactor.

scholarly journals THE IMPACT OF TARGETED TRAINING OF MEDICAL INTERNS ON THE SURVIVAL OF CARDIAC ARREST IN THE EMERGENCY ROOM

2021 ◽  
Vol 9 (11) ◽  
pp. 1167-1176
Author(s):  
Benmessaoudfz a ◽  
◽  
Tadilijawad b ◽  
Kettani Ali ◽  
Ahlam Chaieri ◽  
...  
Keyword(s):  
Cardiac Arrest ◽  
Medical Training ◽  
Discharge Rate ◽  
National Registry ◽  
Primary Objective ◽  
University Hospital ◽  
Significant Difference ◽  
Medical Interns ◽  
The Impact

Introduction:The prognosis of patients with cardiac arrest is closely related to the quality of cardiopulmonary resuscitation (CPR). The aim of this work was to assess the impact of targeted training on CPR, in accordance with the latest international recommendations, on the management of cardiac arrests in SAUV. Methods:This is a prospective study carried out between January 1 and December 31, 2011 at the SAUV of Ibn Sina University Hospital in Rabat, including all adult patients who experienced cardiac arrest after admission. The main primary objective is to evaluate the impact of targeted training of medical interns on the survival of cardiac arrest in the ER expressed by the Hospital Discharge Survival (HDS) rate. Secondary objectives include the rate of recovery of circulatory activity (RCA), 48-hour survival, and quality of CPR performance. Results:342 patients were included, 159 before and 183 after training. There was no significant difference in terms of recovery from spontaneous circulation, 48h survival or discharge rate at home without sequelae. On the other hand, there was a statistically significant improvement in all the quality criteria for performing CPR. Conclusion:This work shows that the introduction of short training courses such improves the quality of CPR. The lack of impact on the improvement of patient survival seems to be related to numerous shortcomings, in particular basic medical training in emergency medicine, organization and protocolization of care, equipment of emergency rooms, supervision of emergency clerkship and the existence of a CA national registry. These are all areas to be developed in order to improve the prognosis of CA in our hospital structure.

scholarly journals A discrete element/shell finite element coupling for simulating impacts on reinforced concrete structures

2010 ◽  
pp. 153-164
Author(s):  
Jessica Rousseau ◽  
Philippe Marin ◽  
Laurent Daudeville ◽  
Sergueï Potapov
Keyword(s):  
Finite Element ◽  
Heterogeneous Media ◽  
Element Model ◽  
Discrete Element ◽  
Impact Zone ◽  
Large Structures ◽  
Coupling Procedure ◽  
The Media ◽  
Shell Finite Element ◽  
The Impact

The efficiency of the discrete element method for studying the fracture of heterogeneous media has been demonstrated, but it is limited by the size of the computational model. A coupling between the discrete element and the finite element methods is proposed to handle the simulation of impacts on large structures. The structure is split into two subdomains in each of which the method is adapted to the behaviour of the structure under impact. The DEM takes naturally into account the discontinuities and is used to model the media in the impact zone. The remaining structure is modelled by the FEM. We propose an extension of the coupling procedure to connect the Discrete Element model to shell-type Finite Elements. The efficiency of the coupling method is tested and validated.

A Numerical Approach for the Determination of the Primary Fabric of Granular Soils

2014 ◽  
Vol 553 ◽  
pp. 489-494 ◽  
Author(s):  
Huu Duc To ◽  
Sergio Andres Galindo-Torres ◽  
Alexander Scheuermann
Keyword(s):  
Soil Structure ◽  
Load Transfer ◽  
Numerical Models ◽  
Element Model ◽  
Discrete Element ◽  
Numerical Approach ◽  
Force Chains ◽  
Soil Fraction ◽  
Element Approach ◽  
Soil Skeleton

Granular soil as a porous medium consists of particles, touching each other and forming a solid skeleton with interconnected pores. The transfer of externally applied loads is in most cases not homogeneous, but takes place mostly in a limited number of particles creating so-called force chains. The assembly of force chains is frequently referred to the primary fabric of a soil. The knowledge of the primary fabric is of vital importance for the analysis of many soil behaviours as, for instance, in the assessment of suffusion. Most of the current numerical models, mostly based on a discrete element approach, generate an artificial soil specimen by creating particles randomly. Therefore, particle position is not under control at all, and as a consequence the influence from particle arrangement on the creation of the primary fabric is neglected. This paper presents a sequential packing method, which allows studying two different types of particle arrangements for a given and constant grain size distribution: (1) layer-wise, producing a layered structure and (2) discrete, leading to a rather homogeneous soil structure. The generated soil specimens are compacted using a discrete element model under oedometric boundary conditions and zero gravity to create force chains within the soil structure. These force chains are then analysed to determine the soil fraction contributing to the load transfer. The results of the study provide an evidence of the influence of the particle arrangements on the appearance of the soil skeleton and the fraction of particles involved.

scholarly journals How to measure the impact of the COVID-19 pandemic on quality of life: COV19-QoL – the development, reliability and validity of a new scale

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Selman Repišti ◽  
Nikolina Jovanović ◽  
Martina Rojnić Kuzman ◽  
Sara Medved ◽  
Stefan Jerotić ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Mental Health ◽  
Clinical Sample ◽  
Controlled Trial ◽  
Reliability And Validity ◽  
Primary Objective ◽  
Clinical Samples ◽  
Strong Positive Correlation ◽  
The Impact

AbstractObjectiveThe primary objective of this paper is to present a short measure of perceptions on the impact of the COVID-19 pandemic on quality of life, along with analysis of its reliability and validity in non-clinical and clinical samples.MethodsThe scale was named The COV19 – Impact on Quality of Life (COV19-QoL) and it consists of six items presented in the form of a 5-point Likert scale. The items (i.e. statements) cover main areas of quality of life with regard to mental health. The scale was administered to 1346 participants from the general population in Croatia (the non-clinical sample) and 201 patients with severe mental illness recruited from four European countries (Bosnia and Herzegovina, Montenegro, North Macedonia and Serbia), constituting the clinical sample. The clinical sample was part of the randomised controlled trial IMPULSE funded by the European Commission. Data on age and gender were collected for both samples, along with psychiatric diagnoses collected for the clinical sample.ResultsMain findings included a high internal consistency of the scale and a moderate to strong positive correlation among participants’ scores on different items. Principal component analysis yielded one latent component. The correlation between participants’ age and their results on COV19-QoL was negligible. Participants’ perceived quality of life was the most impacted domain, whereas mental health, personal safety and levels of depression were the least impacted domains by the pandemic.DiscussionThe COV19-QoL is a reliable and valid scale which can be used to explore the impact of COVID-19 on quality of life. The scale can be successfully used by researchers and clinicians interested in the impact of the pandemic on people experiencing various pre-existing mental health issues (e.g. anxiety, mood and personality disorders) as well as those without such issues.

Mesoscopic numerical approach for fibrin clot formation using discrete element model

2017 ◽  
Vol 2017.30 (0) ◽  
pp. 067
Author(s):  
Ryogo ENOSAKI ◽  
Satoshi II ◽  
Naoki TAKEISHI ◽  
Kenichiro KOSHIYAMA ◽  
Taiki SHIGEMATSU ◽  
...  
Keyword(s):  
Element Model ◽  
Discrete Element ◽  
Numerical Approach ◽  
Fibrin Clot ◽  
Clot Formation ◽  
Discrete Element Model

scholarly journals Experimental Study of Hybrid Rubberized Composite Slabs

2018 ◽  
Vol 64 (4) ◽  
pp. 22-29
Author(s):  
P. Subashree ◽  
R. Thenmozhi
Keyword(s):  
Impact Load ◽  
Crumb Rubber ◽  
Primary Objective ◽  
Total Weight ◽  
Fine Aggregate ◽  
Rubberized Concrete ◽  
Split Tensile Strength ◽  
Composite Slabs ◽  
Complete Failure ◽  
The Impact

AbstractRubberized concrete is made up of scrap tyre rubbers where the fine aggregate is partially replaced by it, as the waste rubber is being a threat to the environment. It is estimated that only 4% of the waste tyre is used in the application of civil engineering and also there is shortage of fine aggregates. The primary objective of this study is to investigate the preliminary concrete properties of M25 and M30 concretes. The fine aggregate is replaced by pre-treated crumb rubber with 10, 15 and 20 % of total weight. Various tests are conducted on the rubberized concrete specimens such as compressive strength, split tensile strength, flexural strength and slump test. The investigation is carried out to determine the impact load behavior of hybrid rubberized composite slabs. In addition 0%, 1%, 1.5%, and 2% of replacement of rubber fibers for total weight of coarse aggregate is also made. The specimen of size 300 mm x 300 mm x 50 mm thickness is subjected to drop hammer test to find its performance against the impact loads. The number of blows for the first crack and complete failure of slab was found and the characteristics were studied.

scholarly journals Numerical Study on the Impact of Gap between Sheets on the Quality of Riveted Single-Strap Butt Joints

Coatings ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1375
Author(s):  
Zhenzheng Ke ◽  
Yongliang Zhang ◽  
Yuchi Liu ◽  
Zhengwei Zhong ◽  
Chunrun Zhu ◽  
...  
Keyword(s):  
Numerical Study ◽  
Tensile Load ◽  
Element Model ◽  
Butt Joint ◽  
Radial Deformation ◽  
Maximum Deformation ◽  
Riveting Process ◽  
Controllable Process ◽  
The Impact

Some controllable process parameters in the riveting process such as the gap between sheets, have an important impact on the quality of a riveted butt joint. In this paper, the finite element model of a riveted single-strap butt joint is established with the help of ABAQUS analysis software, and the riveting process is simulated under five kinds of gaps between sheets. From the perspectives of rivet upsetting size, rivet interference, radial deformation of sheet, and analysis of residual stress around the hole of sheet, the influence of the gap between sheets on the connection quality of the riveted butt joint is summarized. The results show that the left and right sheets will contact each other and there is extrusion stress between the sheets when the gap is zero. When the applied tensile load continues to increase, due to the influence of the secondary bending, the strap sheet responsible for the connection produces warping deformation, and there will be no further contact between the sheets. When the gap between sheets increases from 0 to 2 mm, the maximum deformation of strap sheets increases from 0.876 to 0.927 mm, which proves that the gap between sheets have no significant effect on the deformation of the strap sheet.

scholarly journals Ending the pain of children with severe epilepsy? An audit of the impact of medical cannabis in 10 patients

2020 ◽  
Vol 6 ◽  
pp. 205032452097448
Author(s):  
RR Zafar ◽  
AK Schlag ◽  
DJ Nutt
Keyword(s):  
Seizure Frequency ◽  
Case Series ◽  
Primary Objective ◽  
Medical Cannabis ◽  
Whole Plant ◽  
Ease Of Access ◽  
Financial Burdens ◽  
The Uk ◽  
The Impact

Background Scientific and anecdotal evidence suggest that whole plant cannabis extracts are effective in reducing seizure frequency in individuals with a range of epileptic etiologies. We report a case series of 10 individuals using CBMPs in the UK to treat their conditions. Methods In this retrospective study, we report on patients (aged 2-48) with severe, intractable, childhood onset epilepsies using combined cannabinoid therapy. Carers of patients provided details through the charity ‘End our Pain’ and these data were subsequently analysed. Our primary objective was to assess changes in monthly seizure frequency pre and post initiation of CBMPs. We also report on previous and current AED, CBD:THC daily dose, quality of life and financial costs associated with CBMP private prescription. Change in monthly seizure frequency were assessed using a Wilcoxon Signed-ranks test. Results Of the 10 patients enrolled in the study there was an 97% mean reduction in monthly seizure frequency post initiation of CBMPs which was statistically significant (Z = 0, p < 0·01). We showed a reduction in AED use following initiation of CBMPs from a mean of 8 (±5·98) to 1 (±1·05). All patients were using either Bedrolite or Bedica (Bedrocan International) as their CBMP. Individual daily doses of THC ranged from 6·6mg – 26·5mg and for CBD, 200 mg – 550 mg. Average monthly cost of CBMP was £1816·20. Interpretation Our findings suggest a combination of CBD and THC based products are effective in reducing seizure frequency in a range of epileptic conditions. We highlight the inefficacy of the healthcare system in supporting these patients who bare great personal and financial burdens. We encourage specialist physicians and relevant bodies to permit greater ease of access of these medications to those patients where efficacy has been shown.

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