This case study aims at assessing and understanding the level of ergonomics in manual material handling tasks (loading, granite cutting, concrete mixing, brickwork, and plastering) of civil construction workers and dump truck drivers working in Indian opencast mines. The study involves the determination of the level of musculoskeletal disorder and predicting the most affected body parts due to incorrect working posture. The comprehensive methodology involved in this study includes rapid upper limb assessment (RULA) and rapid entire body assessment (REBA) techniques to find the risk involved in the working posture of the construction workers and dump truck drivers. The study showed that posture adopted in civil construction work and dump truck operators (loading and unloading task) are ergonomically incorrect and may cause musculoskeletal disorder (MSD) related problems in the future. This study also showed that the trunk and wrist are the most affected parts of the body in construction workers and the neck and wrist in case of the dumper operator while performing different tasks.
The research paper reports on the processing of titanium carbide (TiC) strengthened aluminium metal matrix composite using a stir casting method. Al 6061 and TiC were used as starting materials for synthesizing Al-1.5TiC composite in a resistance furnace. The stir casting technique was followed owing to its simplicity and economic benefits. Microstructural studies were carried out using image analyser and micrographs revealed even dispersal of reinforcement in the alloy, while energy dispersive spectroscopy (EDS) and x-ray diffraction (XRD) studies confirmed the presence of corresponding elements and phase in the composite.
A desirable benchmark should be complete from all aspect, holistic in nature and conceptually universal as well as acceptable. This work reviews the related literature and conclude that different types of benchmarking methods are used in different organizations and institutions. The everincreasing demand for continuous improvement of quality and performance in any field or organization leads to benchmarking. Benchmarking is an effective technique, which supports innovative ideas. The present study aims to provide an inclusive review of performance benchmarking. In this work, different types of benchmarking techniques are categorized, and their drawbacks and the research trends are provided to assist researchers and practitioners in conducting new research in this area. A new benchmarking methodology has been suggested which could be acceptable universally for all the heavy earthmoving machines (HEMMs) which provides numerical benchmarked value which can be easily used for the comparison purpose
In order to investigate the effect of different perforation angles (the angle between the perforation direction and the maximum horizontal principal stress which is also called the preferred fracture plane (PFP)) on the fracture initiation and propagation during the hydraulic fracturing of highly deviated well, laboratory experiments of the hydraulic fracturing of the BZ25-1 oilfield had been carried out on the basis of non-dimensional similar criteria by using 400mm3 cement cubes. We built the geometric model of the hydraulic fracturing fractures which considered the influences of the wellbore azimuth (the angle between the wellbore axis and the PFP), the perforation angle and the well deviation. The results showed that: the perforations in the PFP produce plane fracture; the fractures initiate from the perforations at the upper side of the well hole and then turn to the PFP when the perforation angle is 45°; when the well deviation angle and the perforation angle are both larger than 45°, the fracture initiates difficultly from the perforations at the lower side of the well hole, and multi-fractures easily initiate; when the perforation angle is 90°, multi-fractures initiate, such as twisting fracture, plane fracture, horizontal fracture and T-shape fracture, in addition, the fracture cannot initiate from the perforation tunnels; the larger the well deviation angle is, the easier is the multi-fractures initiation. Moreover, it is easier to result in micro-annulus which makes the fractures more complicated during the hydraulic fracturing of highly deviated well when the perforation angle is not along with the PFP. Oriented perforating technology should be applied in highly deviated well to obtain the big single plane fracture.
L’univers numérique s’est développé si rapidement que la question de la confiance peut paraître secondaire. Cependant, à mesure que les usages se diversifient, des comportements viennent amoindrir la confiance en cet espace (fraude, usurpation d’identité, cyberharcèlement). En outre, la collecte massive de données personnelles opérée par les services numériques interpelle. Par ailleurs, la cybercriminalité, la surveillance étatique des communications entravent également la confiance en ligne. Dès lors, un tel espace interroge les mécanismes qui produisent et entretiennent la confiance. Si ces mécanismes de confiance ont dans un premier temps imité les mécanismes classiques, l’univers numérique a progressivement produit des mécanismes de génération et de gestion de la confiance propres, en s’appuyant sur la nature de ce qui le caractérise, l’organisation réticulaire et le traitement des données. Dès lors, l’architecture du tiers de confiance, quelle qu’en soit sa modalité, pose elle-même question et débouche sur l’idée qu’une architecture de réseau, par conception, par elle-même, peut générer la confiance dans les échanges.
