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This study provides an extensive overview of the latest developments in metal surface engineering, including methodologies, characterizations, and applications. The study highlights how important surface engineering is for improving metallic materials’ functionality and performance across a range of sectors. Therefore, a series of techniques are presented in this paper for evaluating design surfaces’ mechanical properties, topological properties, and microstructure. This paper presents a review of current advances in the field, focusing on functionalized surfaces for energy applications, nanostructured coatings for corrosion protection, and biomedical applications of modified surfaces. Since lasers and electron beams are mechanically and tribologically superior, there is a long discussion about their environmental footprint. A special focus in the study is on surface functionalization, nanostructured coatings, corrosion protection, and biological applications, as well as recent developments in the field. The paper also discusses the impact they have on the environment. Surface engineering approaches have long been known to enhance corrosion protection, wear resistance, and component functionality in aerospace, automotive, electronics, and healthcare sectors. Thus, the paper’s conclusion emphasizes that more research and development are needed to overcome constraints and take advantage of emerging trends in surface engineering in order to overcome constraints and take advantage of new trends. The paper provides a solid foundation for future research and development in a range of industries affected by surface engineering.

The frequency of failures in hanger pins of Pakistan Railway carriages has risen to an alarming level. Such as hanger pins have become the reason for the highest number of cases regarding failures of Carriage and Wagons in Pakistan. The pins have been failing after only 3 months while the intended life of these pins was supposed to be 6 months at least. Previously we have been using rectangular cross-section cotter pins in the hanger brackets. Studies have shown that instead a circular cross-section cotter pin can make a major contribution to the lower the value of these fatigue stresses. In this study, we compute and perform the stress and fatigue analysis on the hanger pin assembly using Findley criterion. Findley criterion was used as it most closely resembled in the properties needed to carry out our desired simulation. COMSOL model is used to compute the stresses as well as do the fatigue analysis on the said model. Fatigue usage factor has been used in the COMSOL. The first part contains the analysis on the already in-effect hanger pins of rectangular cross-sectional area. While the second half contains analysis done by changing the cross-section to modified circular shaped hanger cotter pins. The new proposed material proved to have decreased the stresses induced in the components thus increasing its life.

The utilization of cutting tools presents inherent limitations, encompassing sluggish production rates, inconsistent cutting precision, and elevated manufacturing expenses in the cutting of PVC (Poly-Vinyl Chloride) pipes. Addressing these challenges requires a systematic design approach to engineers to build sustainable new mechanism for PVC pipe cutting apparatus capable of streamlined operation. This study endeavours to conceptualize and develop a unique mechanism comprised of Ni-Chrome heated wire as a replacement of traditional cutter. The design focus is aimed at enhancing the cutting operation within low cost and enhanced sustainability. The methodology for machine design encompasses a complete machine design approach for each single component if a machine utilizing Solidworks 2023, complemented by rigorous mathematical design calculations. The outcomes of this study manifest in the creation of a prototype of Ni-Chrome heated wire machine capable of cutting the pipes within thickness range from 20-35mm and more based on the heated capability of wire. Noteworthy advantages of this machine design include expedited manufacturing processes, reduced energy consumption, and enhanced labour efficiency, thereby augmenting overall productivity. Future research avenues are suggested to encompass an analysis of operator safety considerations, establishment of periodic maintenance protocols, automation, and optimization of spare parts accessibility to further refine the efficacy and longevity of the proposed system.

Fused deposition modeling (FDM) is a widely employed additive manufacturing (AM) technique owing to its affordability and availability of equipment and materials. Polylactic Acid (PLA) is one of the most widely used materials due to its low cost, good mechanical properties, and biocompatibility. Mechanical performance is significantly influenced by FDM printing parameters. One of the most critical parameters that affect mechanical properties is infill density. In this study, standardized tests are used to ensure rigorous evaluations of the effects of different infill densities on PLA mechanical properties. Tensile strength, hardness, and impact strength are all considered in a comprehensive analysis. Results are then systematically compared with those of other commonly used FDM filaments, such as Acrylonitrile Butadiene Styrene (ABS) and High-density Polyethylene (HDPE). Through a rigorous experimental trial, we can analyze the effect of infill density on mechanical performance in FDM printing using PLA, ABS, and HDPE.

In this work, pure nickel was reinforced with various contents of h-BN (4 & 8wt.%) and SiC (2, 4, 6 & 8wt.%) prepared via PM route. The synergistic effect of h-BN and SiC on mechanical and microstructural behaviour was investigated. The microstructure and crystal structure were characterized by scanning electron microscope and X-ray diffractometer. The density and microhardness were eveluated via He pycnometer and microhardness tester. SEM results revealed that the exfoliation reduced the particle size of h-BN from approximately 105 nm to 30-40 nm. Furthermore, the addition of h-BN and SiC improved the mechanical properties of the composite. The maximum hardness value of 420 HV was obtained for Ni-8BN-6SiC. This improvement in hardness was attributed to uniform dispersion and high hardness of h-BN and SiC. However, more addition of SiC (>6 wt.%) deteriorated the hardness of the composite due to generated porosity.

Small Modular Lead-based Reactor (SMLR) has generated great interest in academic research all around the world due to its good safety characteristics and relatively high core outlet temperature. In this paper, a Combined Cooling Heating and Power (CCHP) system with usage of absorption heat pump, which couples with a SMLR, was proposed to fulfill the energy demands in remote areas. Thermodynamic analysis was implemented to improve the performance of the CCHP system based on SMLR. To meet the remote areas’ energy needs, the main parameters and mass flow rate of a 35 MWth SMLR design were analyzed. The SMLR CCHP with absorption heat pump system can provide electric power 12.5MWe, heating 9.5MWh, and cooling 2.54MWc. The total energy utilization efficiency of the system can be 69.12 %. This work can provide a reference in the design and optimization of the CCHP system to meet the energy demands in the remote areas.

In the Post-Exxon Era of sequence stratigraphy, various sequence models for the complex stratigraphic records with their response mechanisms are developed. All the models with strong pertinence are endowed, which lead to misapprehension in the conceptual system. Therefore, the standardization of sequence stratigraphy with the aim to provide consistency in the terminology has become an important motive of modern sequence. During the development of sequence stratigraphy, the identification and distinction between normal and forced regression have laid important foundation for the system description of sequence development. This becomes the first step towards the standardization because of model-independent nature. The introduction of model-independent unconventional system tracts in fluvial sequence models, which are low- and high-accommodation system tracts, which turn out to be another successful attempt of towards the standardization of sequence stratigraphy. The four parts of stratigraphic records, which include the complexity and cyclicity in the stratigraphic accumulation process; the non-gradual change and the non-integrity of the stratigraphic records; the variability represented by the diversity of the sequence models and the nature of standardization including variability, will provide more clues and approaches for further sequence stratigraphy development

This paper investigates the Organizational Learning Capabilities (OLC) affect Organizational innovativeness (OI) on organizational performance (OP). The mediating role of IO on relationship between OLC and OP was also been studied. Analysis is based on data collected from 200 respondents drawn from Pakistan’s Telecom Sectors. Multiple regression analysis had been used to test the hypotheses. This study found that both OLC and OI have a positive impact towards OP. OI also mediates the relationship between OLC and OI. Key word: Organizational Learning Capabilities (OLC), Organizational Performance (OP), Organization Innovativeness (OI).

The global environment is gradually deteriorating, and the construction sector is commonly considered as most influential to such issues extending from non-renewable resource depletion to global warming. Developing countries in Asia produce more than 60% of the CO2 emissions and this increases from year to year in the real estate industries. Traditional building materials experience low environmental performance; furthermore, they can lead to several risks related to the environment which consists of the construction process and building operation, such as the diverse emission of hazardous waste. Therefore, green procurement has been considered as a gateway approach for enhancing the environmental performance in the building industry. Since the procurement phase is the early stage of the project lifecycle, it is the most noteworthy to ensure a sustainable future perspective. Therefore, this paper intends to establish a theoretical outlook to exploit the enablers and barriers for promoting green procurement in the construction industry.

Corrosion under insulation (CUI) is a progressive problem for piping systems in oil and gas industries especially in petrochemical and chemical plants due to its catastrophic disasters and consequently its automatic impact on the environment. To ensure CUI problem should not spark sudden surprise in plants, indeterminate factors that contribute to the deterioration of pipes subject to CUI should be recognized and taken care seriously. Operating temperature, type of environment, insulation type, pipe complexity and insulation condition of the pipes are the key factors that cause significant deterioration of pipes due to CUI. As per its varying nature, CUI is difficult to predict as it remains hidden beneath the insulation and gets growth in an ambiguous and abrupt manner. For such an uncertain and critical situation, fuzzy logic is a good choice to be deal with. Thus, in this study, CUI corrosion rate for insulated carbon steel piping systems has been predicted by fuzzy logic using API 581 data. Predicted CUI corrosion rates obtained by the developed fuzzy logic model are committing quite satisfactory results when comparing with API 581 published CUI corrosion rates. At the end of study, sensitivity analysis (SA) of CUI producing factors has also been performed. SA is showing the role of each CUI producing factor in terms of percentage, having participation for the cause of 1 mm/year CUI in pipes. The predicted CUI corrosion rates and SA will help inspection engineers for setting and delivering the risk-based inspection priority for insulated piping systems at their concerned plants.

Land degradation caused by soil erosion remains an important global issue due to its adverse consequences on food security and environment. Geospatial prediction of erosion through susceptibility analysis is very crucial to sustainable watershed management. Previous susceptibility studies devoid of some crucial conditioning factors (CFs) termed dynamic CFs whose impacts on the accuracy have not been investigated. Thus, this study evaluates erosion susceptibility under the influence of both non-redundant static and dynamic CFs using support vector machine (SVM), remote sensing and GIS. The CFs considered include drainage density, lineament density, length-slope and soil erodibility as non-redundant static factors, and land surface temperature, soil moisture index, vegetation index and rainfall erosivity as the dynamic factors. The study implements four kernel tricks of SVM with sequential minimal optimization algorithm as a classifier for soil erosion susceptibility modeling. Using area under the curve (AUC) and Cohen’s kappa index (k) as the validation criteria, the results showed that polynomial function had the highest performance followed by linear and radial basis function. However, sigmoid SVM underperformed having the lowest AUC and k values coupled with higher classification errors. The CFs’ weights were implemented for the development of soil erosion susceptibility map. The map would assist planners and decision makers in optimal land-use planning, prevention of soil erosion and its related hazards leading to sustainable watershed management.

Sparse storage formats are techniques for storing and processing the sparse matrix data efficiently. The performance of these storage formats depend upon the distribution of non-zeros, within the matrix in different dimensions. In order to have better results we need a technique that suits best the organization of data in a particular matrix. So the decision of selecting a better technique is the main step towards improving the system's results otherwise the efficiency can be decreased. The purpose of this research is to help identify the best storage format in case of reduced storage size and high processing efficiency for a sparse matrix.

This paper shows the comparison of temperatures produced in a dry friction clutch disc with different materials during a single engagement to assist in clutch plate design and analysis. A study of usage of different materials for friction lining of clutch disc is required, which will provide improved performance and enhanced life. This investigation is modelled mathematically and solved numerically using finite element method. ANSYS® 15.0 is a dedicated finite element package used for determining the temperature distribution across a clutch disc. In the present work, an investigation of a conventionally used harmful friction lining material asbestos is compared with carbon-carbon composite, S2-glass fibre and aluminium metal matrix composite. The transient thermal analysis of a clutch disc with different materials is performed and the temperature distribution on the clutch system is compared. Simulation results indicate that all the values of the temperature obtained from the analysis of aluminium metal matrix are less than those of asbestos based lining material, therefore clutch disc made up of aluminium metal matrix composite will assure the extended service life and the longer stability due to the fact that the temperature responsible for the wear and tear has been reduced. Furthermore, the slipping time is also considered in this investigation.