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The purpose of this paper is to introduce a simple and convenient method for the landslides study.

This study is based upon the individual case study of three past landslides which may probably prove fatal in the near future. It is useful for the measurement of the horizontal length, longitudinal length, altitude at different points and area of the landslide. These measurements are very helpful in calculating the valley side gradient, longitudinal gradient of the landslide scarp and the volume of the debris generated due to mass movement.

Reactivation of slope instability problems were found along these landslides spots, which will create havoc for the people and a problem for the administration in the near future.

The implication in the paper is that structural and non‐structural mitigation and management strategies are needed.

The evaluation of novel materials such as the acrylonitrile styrene acrylate (ASA) for tribological and mechanical conditions can provide a structural protection against the environmental and wear effects that results in the long-term integrity of the 3 D printed parts. Results of the experimental stage are intended to identify the influence of the printing conditions on the functional characteristics of ASA parts that results in variations of the friction coefficient, wear rate and tensile response. In addition, this study aims to highlight the relevance of printing parameters to avoid the use of chemical post-processing stages, increasing the performance and sustainability of the process.

In this research, an evaluation of the influence of printing parameters of layer thickness and temperature on the mechanical and tribological response have been carried out for ASA specimens manufactured by fused filament fabrication technology. For this purpose, a range of three different values of thickness of fused layer and three different printing temperatures were combined in the manufacturing process of tests samples. Mechanical behavior of the printed parts was evaluated by standard tensile tests, and friction forces were measured by pin-on-disk tribological tests against steel spheres.

Higher layer thickness of the printed parts shows lower resistance to tribological wear effects; in terms of friction coefficient and wear rate, this type of parts also presents lower tensile strength. It has been detected that mechanical and tribological behavior is highly related to the micro-geometrical characteristics of the printed surfaces, which can be controlled by the manufacturing parameters. Under this consideration, a reduction in the coefficient of friction near to 65% in the average value was obtained through the variation of the layer thickness of printed surfaces.

This research aims to fill a gap in the scientific literature about the use of specific additive manufacturing materials under dynamic contact. This paper is mainly focused on the influence of the manufacturing parameters on the tribological and mechanical behavior of a weather resistant polymer (ASA).

In the aftermath of hurricanes, the damage levied on transportation infrastructures increases the timeliness of emergency responses and recovery procedures, making it essential that they are reconstructed as quickly as possible – on time and within budget. The aim of this study was to determine significant performance indicators (PIs) that considerably affect cost and schedule performance as well as reworks in post–hurricane reconstruction of transportation infrastructure including highways, bridges, roadways, etc. Additionally, the determined PIs were clustered to investigate key components.

The root causes of reconstruction projects' poor performance were identified through the existing literature, and 30 transportation infrastructure case studies were analyzed to determine the significant PIs that corresponded to cost, schedule performance and reworks. The factor analysis method was used to cluster the significant PIs and determine the key components affecting them.

Eight key components were found for cost, eight for schedule performance and six for reworks. The key components of cost performance are shortage of resources, information management, coordination, safety, location, quality of materials, quality of resources and project complexity. The key components of reconstruction schedule performance are human resources, risk management, work suspension, material resources, productivity, on-site inspections, geometrical characteristics and level of reconstruction complexity. The six key components of reconstruction reworks are logistic management, pace of decision-making, accommodation for staff, environmental issues, available temporary paths and volume of debris.

The outcomes of this research will assist authorities and decision makers in identifying and evaluating the critical root causes of poor cost performance, poor schedule performance and reworks and will enable them to facilitate the timely and effective allocation of resources.

The paper aims to monitor the condition of heavy Earth-moving machines (HEMMs) used in open cast mines by lube oil analysis.

Oil samples at periodic interval were collected from the HEMM engine (Model No: BEML BH50M). Ferrography and Field Emission Scanning Electron Microscopy have been used for the wear particle analysis present in oil samples. Viscosity analysis and Fourier transform infrared spectroscopy have been done to investigate the degradation in quality and changes as compared to the initial structural properties of the lubricants.

The results obtained indicates wear in cylinder liner and piston ring. Copper, cast iron, alloy steel and ferrous oxide have been found as rubbing wear particles and cutting wear particles. Contamination level has also been found to be increasing in consecutive older oil samples. Chemical properties degraded with usage time and variations in oxidation and soot level have also been observed in every sample.

The results will be very much useful to maintenance teams of mining industry for early prediction of any impending failure of the machines, for example, diesel dilution, severe wear of the piston or cylinder liner leading to seizure can be predicted.

The HEMMs are an important piece of equipment in coal mining. Proper condition monitoring of HEMM is required to reduce the break down and down time to increase production.

The study aims to compare tribological properties between laser dimple textured surface and drilled dimple textured surface, and to analyze the influence of dimple hardened edges and ability of trapping wear debris on wear properties of dimple textured surfaces.

Circular textured dimples were produced on AISI 1,045 specimen surfaces using laser surface texturing (LST) and drilled surface texturing (DST) methods. Tribological behaviors of LST, DST and non-textured specimens were studied using ball-on-disc tribo-tester. Metallographic structures, dimples and worn surface morphologies were observed using a three-dimensional digital microscope. Hardnesses of substrate and dimple edges were measured.

There was no obvious difference in wear and friction coefficients between LST and DST specimens. Hardnesses of laser dimple edges were much higher than that of drilled dimple edges and specimen substrate. The hardened materials of laser dimple edge included recast zone and heat affect zone. Laser dimple was cone-shaped and drilled dimple was cylinder-shaped. Drilled dimple had a better ability of trapping wear debris than laser dimple. Non-uniform wear phenomenon occurred on worn surfaces of LST dimple specimens.

The ability of textured dimples to trap wear debris is affected by single dimple volume. Hardened edges of dimples cause non-uniform wear on worn surfaces of LST specimens.

Coordinating interdependencies between concurrent activities is a special challenge in managing increasingly complex building services projects. Effective coordination at the pre‐installation stage is key to minimising field conflicts between building services systems. This study aims to investigate the significant causes of production shortcomings traceable to the pre‐installation stage, and to what extent these in turn probably contribute to higher volumes of construction debris.

Following relevant previous research and preliminary studies of production shortcomings in the building services subsector in Hong Kong, a series of structured interviews with practitioners were formulated and analysed. The findings lead to deductive reasoning in developing suitable approaches for this subsector.

The study reveals that “poor coordination among different trades and processes”, and “frequent design changes and/or errors” are seen as two of the major causes of production shortcomings in the pre‐installation stage. This paper proposes and discusses improvement strategies based on conceptual models of an “intra‐inter dependent teamwork concept”, a “dynamic coordination buffer” and a “BS coordination facilitator” in order to reduce the identified critical causes.

Although further research is needed, the findings in this paper can be a useful reference for other regions as the study methodology may be replicated.

In the search for solutions and improvements, a number of proven industrial management principles are incorporated in new conceptual models. These are expected to help alleviate the identified causes as critical design or related uncertainties are resolved through earlier coordination. This should in turn also reduce the volume of construction debris that can arise from current shortcomings in the pre‐installation stage of building services.

This paper aims to investigate the temperature and wear properties of vertical ball screws and to discuss the surface design of ball screws in industrial applications.

The energy equation of the screw surface considering the frictional heat was established to verify the surface temperature of the ball screw. X-ray diffraction was used to examine the micro-contact temperature between the ball and screw. Debris size and density were examined to investigate wear properties of ball screws and to study the relationship of wear debris and temperature.

First, the main energy source for the surface temperature of high speed vertical ball screws is derived from friction force between ball and screw. Second, the temperature rise between the ball and screw has great relevance with wear debris concentration. Third, the surface temperature of the screw is higher than between the nut and ball for high speed vertical ball screws due to high convection heat transfer. The contact temperature of the nut near the flange is smaller than that of the nut away from the flange end due to the high contact load and thermal conduction. Finally, correlation of particle size and surface roughness value for vertical ball screws was established, and its effects on contact temperature were studied. The theoretical analysis and experiments will help to characterize the design and manufacture of vertical ball screws.

The surface temperature and micro-contact temperature analytical model were established to study the ball screw design. Based on the surface-particle micro-contact temperature balance, the optimal range of surface roughness was designed for vertical ball screws, considering the wear debris and micro-contact temperature.

The aim of this paper is to present a discussion on prognosis and mitigation of major landslide zones in an attempt to minimize the impact of such disasters in future. A case study on the sequence of sliding events of Varunavat Parvat, Uttarkashi (India), response of masses and administration and causative factors of sliding events has been presented in detail for prognosis and mitigation of large slide zones.

The prognosis and mitigation strategy discussed is based on the monitoring of mass wasting zones through field investigations and satellite image analysis (of pre‐ and post‐landslide period images) and experiential learning and interaction with village elders in landslide hazard‐prone Himalayan terrain.

The paper finds that Himalayan habitations such as Uttarkashi (which is situated in an area of fragile rocks, complex tectonics, seismic activity and cloud burst‐prone unstable hill slopes with colluvium and old slide zones) should have minimum anthropogenic activity in the form of slope cutting for road or building construction.

The paper reflects the author's individual understanding of causative factors and indications of landslides in Varunavat Parvat area in Uttarkashi township of Uttarakhand (India).

The paper calls for amalgamation of experience‐based local knowledge of villagers of landslide‐prone areas and modern scientific and technical know‐how and above all the coordinated efforts of community and authorities for prognosis and mitigation of large‐scale landslides in the inhabited areas. It has been further emphasized that sensitization and awareness programs and strict implementation of land‐use regulations are vital components of effective mitigation strategy.

The purpose of this paper is to demonstrate laser microvia drilling of polyimide thin films from multiple sources before metallic sputtering. This process flow reduces Flexible Printed Circuit Board (FPCB) material, chemical and operational costs by 90 per cent in the construction of flexible circuits.

The UV laser percussion drilling of microvias in 25 μm thick polyimide films with low coefficients of thermal expansion (CTE) and elastic modulii was investigated. Results were obtained using Scanning Electron Microscopy and Surface Profilometry. Polyimide films tested included: Dupont™ Kapton^® EN; Kolon^® GP and LV; Apical^® NPI; and Taimide™ TA‐T.

There was no direct relationship between the top and bottom diameters and ablation depth rates between the polyimide films tested using the same test conditions. There was a direct relationship with exit diameters and etch rates at different laser pulse frequency rates and fluence levels. Laser pulse rates at 30 kHz produced 20 per cent larger exit diameters than at 70 kHz, however at 70 kHz the first pulse etched 16.5 per cent more material. High fluence levels etched more material but with a lower etch efficiency rate. Other microvia quality concerns such as surface swelling, membrane residues on the bottom side and surface debris inside the microvias were observed. Nanoscale powder‐like surface debris was observed on all samples in all test conditions.

This is the first comparison of material specifications and costs for films from multiple polyimide manufactures and laser microvia drilling. The paper also is the first to demonstrate results using a JDSU™ Lightwave Q302^® laser rail. The results provide the first insights into potential microvia membrane issues and debris characteristics.