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1. Impact de la carence en vitamine D sur la récupération fonctionnelle après fracture du col du fémur chez les patients âgés hospitalisés en soins de suite et réadaptation orthogériatrique

Author:
F. Lecomte; M. Martinez-Caballero; N. Camsonne-Pioline; J. Cohen-Bittan; J. Boddaert; A. Meziere
Source:
Nutrition clinique et métabolisme 2022 v.36 no.1 pp. S45
ISSN:
0985-0562
Subject:
chutes,   etc   ; locomotion; methodology; nutrition; patients;     Show all 5 Subjects
Abstract:
... La fracture de l’extrémité supérieure du fémur (FESF) chez le sujet âgé constitue une complication grave de l’ostéoporose en termes de pronostic fonctionnel. La carence en vitamine D constitue un facteur de risque indépendant de fracture et est associée à une baisse de la fonction musculaire, notamment chez le sujet âgé, et donc augmente le risque de chute. De plus, il a été démontré une associati ...
DOI:
10.1016/j.nupar.2021.12.087

2. Reduction mechanism of the normal stress exerted on silo wall with chutes during eccentric discharge

Author:
Zhijun Xu; Pengfei Liang; Yuanhao Cheng; Yang Zhou
Source:
Powder technology 2022 v.407 pp. 117659
ISSN:
0032-5910
Subject:
chutes,   etc   ; analytical methods; crossing; feet; forces; powders; silos; technology; walls;     Show all 9 Subjects
Abstract:
... This paper studied the reduction mechanism of wall normal stress exerted on silo wall with chutes during eccentric discharge utilizing the experiment and analytical methods. The result shows that the chute leads to form a new flow chamber and drives the original flow chamber to move to the center of the silo. The double flow chamber makes the granular materials flow out orderly from the discharge ...
DOI:
10.1016/j.powtec.2022.117659

3. Inception Point for Stepped Chute Designs with Multiple Sections of Different Step Heights

Author:
Hunt Sherry L.; Kadavy Kem C.
Source:
Journal of hydraulic engineering 2021 v.147 no.4 pp. -
ISSN:
0733-9429
Subject:
chutes,   etc   ; bioinformatics; design; dynamic models; exhibitions; fluid mechanics; height; hydraulic engineering; journals; model validation; prediction; surfaces; wills;     Show all 13 Subjects
Abstract:
... In the literature, a classical free-surface inception point empirical relationship for smooth chutes serves as a basis for the development of a free-surface inception point relationship for stepped chute applications. This study expands research on the free-surface inception point for stepped chutes with multiple sections with different step heights along the chute bottom surface. Data show that e ...
Handle:
10113/7709333
DOI:
10.1061/(ASCE)HY.1943-7900.0001848

4. Optimization of a convex pattern surface for sliding wear reduction based on a definitive screening design and discrete element method

Author:
Yunpeng Yan; Rudy Helmons; Craig Wheeler; Dingena Schott
Source:
Powder technology 2021 v.394 pp. 1094-1110
ISSN:
0032-5910
Subject:
chutes,   etc   ; particles; powders; regression analysis; rolling; rolls; screening; surfaces; technology;     Show all 9 Subjects
Abstract:
... A previous study revealed that a convex pattern surface can reduce sliding wear of a transfer chute. A convex pattern surface is a flat surface outfitted with a pattern of convexes defined by five parameters. A three-level definitive screening design (DSD) method combined with discrete element method (DEM) is used to investigate the influence of the five parameters and two operational conditions o ...
DOI:
10.1016/j.powtec.2021.09.041

5. Effect of bend angle on granular size segregation in the chute flow under periodic flow inversion

Author:
Bhargav Mantravadi; Danielle S. Tan
Source:
Powder technology 2020 v.360 pp. 177-192
ISSN:
0032-5910
Subject:
chutes,   etc   ; industry; mixing; powders;     Show all 4 Subjects
Abstract:
... Segregation of granular homogeneous mixtures is a common problem faced by many industries. In recent years, periodic flow inversions have shown to mitigate both size and density segregation. However, they are not fully explored. In this paper, we investigate the effect of bend angle (θ) in the chute flow using three-dimensional Discrete Element Method (DEM) simulations. We observed a significant d ...
DOI:
10.1016/j.powtec.2019.10.005

6. Experimental measurement of granular flow layers in the chute

Author:
S.S. Wang; R. Li; Q. Chen; G. Zheng; V. Zivkovic; H. Yang
Source:
Powder technology 2020 v.376 pp. 22-30
ISSN:
0032-5910
Subject:
chutes,   etc   ; exhibitions; granules; particle image velocimetry; particles; powders; rolling; rolls; surfaces; technology;     Show all 10 Subjects
Abstract:
... In this paper, the particle image velocimetry (PIV) and the embedded inertial navigation techniques were used to measure the particle movement of granular flow in the chute. And the basal layer, core layer, and surface layer of the system were recognized more accurately and quantitatively giving the thickness of each region, where the effects of particle angular velocity and rolling contribution r ...
DOI:
10.1016/j.powtec.2020.07.112

7. Discrete element modelling of a chevron patterned conveyor belt and a transfer chute

Author:
J. Rossow; C.J. Coetzee
Source:
Powder technology 2021 v.391 pp. 77-96
ISSN:
0032-5910
Subject:
chutes,   etc   ; analytical methods; conveyors; guidelines; materials; measurement; models; particles; powders; prediction; rocks; systems engineering; technology;     Show all 13 Subjects
Abstract:
... The Discrete Element Method (DEM) is increasingly used to analyse the design of conveyor systems. In this study, the capability of, and accuracy with which DEM can predict the flow of a non-cohesive granular material through a transfer chute was investigated. The model included a Chevron patterned belt, an impact plate, hood, and rock box. The results were compared to measurements using high-speed ...
DOI:
10.1016/j.powtec.2021.06.012

8. Nappe flows on a stepped chute with prototype-scale steps height: Observations of flow patterns, air-water flow properties, energy dissipation and dissolved oxygen

Author:
Stefan Felder; Margaux Geuzaine; Benjamin Dewals; Sebastien Erpicum
Source:
Journal of hydro-environment research 2019 v.27 pp. 1-19
ISSN:
1570-6443
Subject:
chutes,   etc   ; aeration; dissolved oxygen; energy; laboratory experimentation; spillways;     Show all 6 Subjects
Abstract:
... Air-water flows occur commonly in stepped spillways including the nappe flow regime for low flow rates. The present laboratory experiments researched the nappe flow regime in a stepped chute with prototype-scale steps height providing unique insights into the evolution of nappe flows along a stepped chute. Detailed visual observations highlighted the varying flow features along the stepped chute i ...
DOI:
10.1016/j.jher.2019.07.004

9. Effects of obstacle's curvature on shock dynamics of gravity-driven granular flows impacting a circular cylinder

Author:
Zheng Chen; Dieter Rickenmann; Yi Zhang; Siming He
Source:
Engineering geology 2021 v.293 pp. 106343
ISSN:
0013-7952
Subject:
chutes,   etc   ; accelerometers; engineers; flow; geophysics; hazard characterization; image analysis; infrastructure; laboratory experimentation; mass movement; pressure; processing technology; rocks; shape; surfaces;     Show all 15 Subjects
Abstract:
... Granular flows, such as rock avalanches and debris flows, are gravity-driven and often hit engineering structures that are placed in their paths, generating dynamic impact pressures and potentially causing hazard to infrastructures. To improve the design of protective structures and the hazard assessment, it is important to understand the physical mechanism of such granular flows impacting on obst ...
DOI:
10.1016/j.enggeo.2021.106343

10. Modelling bulk solid flow interactions in transfer chutes: Shearing flow

Author:
D. Ilic; A. Roberts; C. Wheeler; A. Katterfeld
Source:
Powder technology 2019 v.354 pp. 30-44
ISSN:
0032-5910
Subject:
chutes,   etc   ; case studies; coal; conveyors; mechanics; models; powders; quantitative analysis; transportation;     Show all 9 Subjects
Abstract:
... In the field of handling, storage and transportation, chutes are used to transfer bulk solids between conveyors. In these systems, traditional analysis methods based on the principle of continuum mechanics approximate an accelerated stream that incorporates physical bulk solid properties obtained from standardised tests. Due to difficulties in physically observing the flow within the transfer stru ...
DOI:
10.1016/j.powtec.2019.05.058

11. Hydraulic Jumps in Adverse-Slope Stilling Basins for Stepped Spillways

Author:
Robert Ljubičić; Budo Zindović; Predrag Vojt; Dragutin Pavlović; Radomir Kapor; Ljubodrag Savić
Source:
Water 2018 v.10 no.4 pp. -
ISSN:
2073-4441
Subject:
chutes,   etc   ; aeration; air; basins; energy; spillways;     Show all 6 Subjects
Abstract:
... The performance of flat stilling basins can be inadequate for conditions when the tailwater depth is insufficient for hydraulic jump stabilization. In such cases, adverse-slope stilling basins can be used because they reduce the necessary tailwater depth. Sloped basins combined with smooth chutes have been the subject of many studies. However, limited research has been done for basins with stepped ...
DOI:
10.3390/w10040460

12. Analysis of Wet Soil Granular Flow down Inclined Chutes Using Discrete Element Method

Author:
Chuan Zhao; Linlin Jiang; Xin Lu; Xiang Xiao
Source:
Water 2019 v.11 no.11 pp. -
ISSN:
2073-4441
Subject:
chutes,   etc   ; adhesion; avalanches; cohesion; disasters; kinetic energy; landslides; mathematical models; soil structure; surface tension; van der Waals forces;     Show all 11 Subjects
Abstract:
... This paper presents numerical simulation and analysis of two numerical experiments of wet soil granular flow down inclined chutes based on the JKR(Johnson-Kendall-Roberts)-cohesion model of the discrete element method. JKR is a cohesive contact model, which can reflect the influence of van der Waals forces in the contact range to simulate cohesive granular matter. A surface energy coefficient k
DOI:
10.3390/w11112399

13. Aeration efficiency of bottom-inlet aerators for spillways

Author:
M. Cihan Aydin
Source:
ISH journal of hydraulic engineering 2018 v.24 no.3 pp. 330-336
ISSN:
2164-3040
Subject:
chutes,   etc   ; aeration; aerators; air; spillways;     Show all 5 Subjects
Abstract:
... The bottom-inlet aerator can efficiently protect a spillway chute surface from cavitation damage due to high-flow velocities. This aerator, unlike conventional ones, is especially preferred at low Froude numbers and with wide spillway chutes to overcome submerged aerator conditions. In this study, the aeration performance of bottom-inlet aerators was investigated for different Froude numbers and r ...
DOI:
10.1080/09715010.2017.1381576

14. Characteristics of landslide-debris flow accumulation in mountainous areas

Author:
Zhang Qing-zhao; Pan Qing; Chen Ying; Luo Ze-jun; Shi Zhen-ming; Zhou Yuan-yuan
Source:
Heliyon 2019 v.5 no.9 pp. e02463
ISSN:
2405-8440
Subject:
chutes,   etc   ; accidents; area; exhibitions; mathematical models; mountains; particle size distribution; particles; surfaces; testing; valleys;     Show all 11 Subjects
Abstract:
... Landslide-debris flow is a sudden geological hazard in mountain areas, which is characterized with large scale, fast speed and wide impact range, and often causes disastrous accidents. In this study, an indoor sliding chute test was used to study the movement process of the landslide-debris flow and its accumulation pattern in the valley, taking into account the initiated gradient and particle siz ...
DOI:
10.1016/j.heliyon.2019.e02463
PubMed:
31687562
PubMed Central:
PMC6819775

15. USBR Type III and Type IV Stilling Basins and Rock Aprons Associated with Stepped Chutes

Author:
Sherry L. Hunt; Kem C. Kadavy
Source:
Applied engineering in agriculture 2018 v.34 no.2 pp. 389-394
ISSN:
0883-8542
Subject:
chutes,   etc   ; Agricultural Research Service; agricultural engineering; basins; energy; hydraulic engineering; prototypes; water flow; Oklahoma;     Show all 9 Subjects
Abstract:
... Stilling basins are commonly used as energy dissipators for structural chutes. Classical research conducted by scientists of the U. S. Bureau of Reclamation (USBR) led to the development of design criteria for a variety of stilling basin configurations as the outlet works for smooth chutes, but little is known about the performance of these dissipators when paired with stepped chutes. Research at ...
DOI:
10.13031/aea.12638

16. Reenvisioning velocity reversal as a diversity of hydraulic patch behaviours

Author:
Michael A. Strom; Gregory B. Pasternack; Joshua R. Wyrick
Source:
Hydrological processes 2016 v.30 no.13 pp. 2348-2365
ISSN:
0885-6087
Subject:
chutes,   etc   ; hydrodynamics; hydrology; models;     Show all 4 Subjects
Abstract:
... Past research investigated the surpassing of mean velocity at riffle cross sections by that at pool cross sections for flows up to bankfull, termed ‘velocity reversals’, to understand one mechanism by which riffle–pool relief is maintained. This study reenvisioned the classic velocity reversal by documenting stage‐dependent changes to the locations of peak velocity without cross sections. Instead, ...
DOI:
10.1002/hyp.10797

17. Static and dynamic compressive loading of fired iron ore pellets

Author:
Pedro P. Cavalcanti; Luís Marcelo Tavares
Source:
Powder technology 2019 v.354 pp. 281-288
ISSN:
0032-5910
Subject:
chutes,   etc   ; deformation; energy; impact load; iron; mechanical properties; pellets; powders; quality control; screening; ships; silos; wagons;     Show all 13 Subjects
Abstract:
... Slow compression tests are routinely used both in quality control of fired iron ore pellets during production and in negotiating commercial contracts. In spite of their widespread use, such tests represent stressing conditions consistent with those experienced by pellets during transportation in ships, wagons and conveyor belts, as well as when they are stored in silos and hoppers. However, operat ...
DOI:
10.1016/j.powtec.2019.06.006

18. Suicide in parachuting: A case report and review of the literature

Author:
Pierre-Antoine Peyron; Emmanuel Margueritte; Eric Baccino
Source:
Forensic science international 2018 v.286 pp. e8
ISSN:
0379-0738
Subject:
chutes,   etc   ; altitude; case studies; death; forensic sciences; humans; jumping; necropsy; police; suicide;     Show all 10 Subjects
Abstract:
... Skydiving fatalities are mostly accidental and the result of human errors. However, suicides may be greatly underreported in skydivers. We present the case of a young civilian skydiver who committed suicide by jumping from an altitude of 4000m without activating his chutes. Witnesses reported that the victim had remained in a freefall position until ground impact. Besides an extensive blunt trauma ...
DOI:
10.1016/j.forsciint.2018.03.006

19. Effect of a baffled chute on stream habitat conditions and biological communities

Author:
Aneta Bylak; Krzysztof Kukuła; Karol Plesiński; Artur Radecki-Pawlik
Source:
Ecological engineering 2017 v.106 pp. 263-272
ISSN:
0925-8574
Subject:
chutes,   etc   ; ecosystems; fauna; fish; habitats; hydraulic structures; invertebrates; raceways; rivers; stream channels; wastewater; Poland;     Show all 12 Subjects
Abstract:
... Despite the occurrence of many low head hydraulic structures in rivers, such as drop hydraulic structures or boulder ramps, there is still a lack of information on how these structures influence stream habitat conditions and biological communities. This lack of knowledge especially applies to baffled chutes, which, to date, have not been the subject of any hydrobiological studies. Our study examin ...
DOI:
10.1016/j.ecoleng.2017.05.049

20. Age-0 Sturgeon Accessibility to Constructed and Modified Chutes in the Lower Missouri River

Author:
Nathan J. C. Gosch; Marcus L. Miller; Todd R. Gemeinhardt; Schuyler J. Sampson; Joseph L. Bonneau
Source:
North American journal of fisheries management 2015 v.35 no.1 pp. 75-85
ISSN:
1548-8675
Subject:
chutes,   etc   ; Scaphirhynchus; habitats; sturgeon; Missouri River;     Show all 5 Subjects
Abstract:
... Shallow-water habitat is hypothesized to provide nursery habitat for young fish. The construction of side-channel chutes to restore shallow-water habitat is common in the lower Missouri River; however, a recent adaptive management strategy document (developed by a multiagency, multidiscipline team), as well as previous research, has suggested that the accessibility of chutes to age-0 Scaphirhynchu ...
DOI:
10.1080/02755947.2014.975300