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The purpose of this paper is to discuss the performance of efficient cold-formed steel (CFS) sections in building a truss system. A comparative study was performed comparing trusses built with cold-formed and hot-rolled sections.

Medium-scale specimens were fabricated and tested under monotonic loading. Closed CFS sections (tubular sections) were adopted as compression members of the truss, against the open sections (angle sections) in the hot-rolled steel truss. While as open sections (angle sections) were adopted as tension members in both these cases, the performance assessment was made on the basis of the peak loads carried by the trusses, the vertical deflections and the failure modes exhibited.

The results of this study indicated that the overall strength, strength-to-weight ratio and overall convenience in terms of cost and fabrication, in the CFS truss was better than that of the hot-rolled one. Also, the judicious utilization of steel which has limited reserves can be achieved.

Cold-formed and hot-rolled sections are widely used in the steel structures. There are advantages and disadvantages in using each of these configurations, discussed in this work. The advantages are widely known by the scientific community; however, few studies are developed with the purpose of quantifying the gains of each solution. Thus, this work emerges with great innovation, with regard to the experimental evaluation of the trusses' behavior composed of different structural sections.

Recently, the utilization of cold-formed steel (CFS) roof truss systems and different types of other combination structural support systems, such as concrete or hot-rolled steel support, becomes more frequently used. This paper aims to identify the load transfer characteristics of three different design details for cold-formed truss to supporting system connections and to propose simplified modelling approach for practices.

Simplification modelling of connection design could be proposed for practical purpose based on the load transfer characteristics obtained from detailed study using finite element method. A cold-formed roof truss system with connection is modelled using line elements. However, the supporting system is not modelled in this work. Three types of connection involve, which are five pieces of CFS L-angle brackets, one-piece of CFS L-angle brackets and three types of bolts connection are modelled.

The results of analysis show that the connections located on the loaded side experienced higher reactions than those far from loaded side. From the result, it is also found that the option of “Fixed But” support condition in STAAD.Pro with translational degree of freedom being restrained is the most suitable way to represent the CFS L-angle brackets design for Type 1 connection for use in truss modelled using line elements.

Such increase in usage necessitates an appropriate connection detailing depending on the behaviour of the connection.

In this work, a numerical algorithm is presented for stability analysis of cold-formed steel (CFS) channel sections.

A nonlinear optimization problem is formulated using energy-based technique of idealized channel section subject shear, compression and biaxial bending. The total potential energy is minimized with respect to skew angle and half wavelength of the buckling mode. The optimization algorithm is updated sequentially using quadratic approximation until minimum buckling coefficient is attained. The developed algorithm is validated using other numerical techniques.

The described algorithm is computationally effective and can be utilized in the industry for analysis of CFS channels under any load combination.

The paper offers a new tool for engineers in practice to analyze channels subject to combined loadings.

Very limited literature dealt with the stability of channels under combined loading. A new numerical algorithm is provided to practitioners to utilize in the industry for analysis of channel sections under combined loading. Unlike finite element or finite strip methods, the channel is not discretized into subelements. Mathematical programming technique is used to find the buckling load. Parametric studies are then carried out to highlight influences of geometric interaction of the channel components and to provide useful guidance to the design of CFS channels.

The capability of steel columns to support their design loads is highly affected by the time of exposure and temperature magnitude, which causes deterioration of mechanical properties of steel under fire conditions. It is known that structural steel loses strength and stiffness as temperature increases, particularly above 400 °C. The duration of time in which steel is exposed to high temperatures also has an impact on how much strength it loses. The time-dependent response of steel is critical when estimating load carrying capacity of steel columns exposed to fire. Thus, investigating the structural response of cold-formed steel (CFS) columns is gaining more interest due to the nature of such structural elements.

In this study, experiments were conducted on two CFS configurations: back-to-back (B-B) channel and toe-to-toe (T-T) channel sections. All CFS column specimens were exposed to different temperatures following the standard fire curve and cooled by air or water. A total of 14 tests were conducted to evaluate the capacity of the CFS sections. The axial resistance and yield deformation were noted for both section types at elevated temperatures. The CFS column sections were modelled to simulate the section's behaviour under various temperature exposures using the general-purpose finite element (FE) program ABAQUS. The results from FE modelling agreed well with the experimental results. Ultimate load of experiment and finite element model (FEM) are compared with each other. The difference in percentage and ratio between both are presented.

The results showed that B-B configuration showed better performance for all the investigated parameters than T-T sections. A noticeable loss in the ultimate strength of 34.5 and 65.6% was observed at 90 min (986℃) for B-B specimens cooled using air and water, respectively. However, the reduction was 29.9 and 46% in the T-T configuration, respectively.

This research paper focusses on assessing the buckling strength of heated CFS sections to analyse the mode of failure of CFS sections with B-B and T-T design configurations under the effect of elevated temperature.

The progress of a nation is quite closely linked with the quality of education it offers its citizens. The onus of nurturing future leaders, the students, lies significantly with higher educational institutions (HEIs) and the academic staff associated with such institutions. Therefore, HEIs need so that these engaged employees may go on to look beyond regular extrinsic motivators to ensure employee engagement to mentor students effectively. In this study, we attempted to investigate the influence of an important predictor of employee engagement, leadership, specifically servant leadership style mediated through job satisfaction. A structured questionnaire was administered to the academic staff of the top 25 universities in India. The data collected and the proposed hypotheses were tested using structural equation modeling. The results confirmed that job satisfaction mediates the relationship between servant leadership and work engagement. The study offers insights into the importance of servant leadership to foster employee engagement and thereby institutional effectiveness in the educational sector.

The purpose of this paper is to assess the influence of blends of Jatropha methyl ester (JME) and its nano Al₂O₃ emulsion on variable compression ratio diesel engine. The oxygen in alumina contributed for the smooth burning and resulted in improved performance and emissions.

The biodiesel (methyl ester) is prepared from the raw Jatropha oil. The B10, B20 and B30 blends of and their nanoemulsions are prepared with the 25, 50, 75 and 100 ppm of nano Al₂O₃. The prepared JME blends and its nanoemulsions are tested in a variable compression ratio (VCR) diesel engine to evaluate the engine performance and emission characteristics.

The nanoemulsion B20 + 50 ppm has given maximum brake thermal efficiency (BTE), and with the increased proportion of nanoparticle, the BTE was reduced. Also, the specific fuel consumption is lowest (0.2826 kg/kWh) for B20 + 50 ppm at the compression ratio 16.5 and full load which is 4.10% lower than the diesel and 5.8% lower than the B20 blend. As the load increases, NOx emission increases owing to higher peak temperatures in the combustion chamber. The JME-nano Al₂O₃ emulsion reduces the HC and CO emission compared with all other fuels.

Novel nano emulsions are prepared, characterized and tested on VCR engine.

Selecting and using the same health monitoring devices for a particular problem is a tedious task. This paper aims to provide a comprehensive review of 40 research papers giving the Smart health monitoring system using Internet of things (IoT) and Deep learning.

Health Monitoring Systems play a significant role in the healthcare sector. The development and testing of health monitoring devices using IoT and deep learning dominate the healthcare sector.

In addition, the detailed conversation and investigation are finished by techniques and development framework. Authors have identified the research gap and presented future research directions in IoT, edge computing and deep learning.

The gathered research articles are examined, and the gaps and issues that the current research papers confront are discussed. In addition, based on various research gaps, this assessment proposes the primary future scope for deep learning and IoT health monitoring model.

As the companion paper of Part I, this paper aims to get more insight into the essence of lambda and to reveal its nature and role in the transition of lubrication states. Mixed lubrication (ML) model with micro-asperities contacts has been discussed in details in Part I.

Mimetic algorithm is used to get numerical solutions. Relationships between film thickness ratios and lubrication states transition with different external loads, rotating speeds, radial clearances, elastic modulus, surface hardness and roughness parameters are obtained.

The characteristic parameters of transitions from boundary lubrication (BL) to ML and ML to hydrodynamic lubrication (HL) are studied to determine how these parameters change with above factors. Finally, the essence and major influencing factors of lambda are summarized for such bearings.

In Part II, the authors believe that the paper presents for the first time: further insight into the essence of the lambda ratio, and its role in the lubrication states transition are given; the determinations of the characteristic parameters of transition from BL to ML and ML to HL are investigated for the first time; the characteristic parameters of transitions from BL to ML and ML to HL are also studied to determine how parameters (external load, rotating speed, radial clearance, elastic modulus, surface hardness and roughness parameter) change with above factors; a summary of the essence and major influencing factors of lambda for such bearings is given.

Biopigments, natural colors from microbiological origin are of great interest because of their potential advantages over synthetic colorants. Therefore, this paper aims to evaluate the best possible fermentative conditions for the maximum production of biopigment using solid state fermentation and submerged fermentation by Monascus purpureus MTCC 369.

The biopigment was produced using solid state fermentation and submerged with optimized substrate to achieve higher yield. The statistical analysis was carried out using a Microsoft Excel ® (Microsoft Corporation).

On comparative analysis, it was observed that solid state fermentation resulted significant accumulation of biopigment (9.0 CVU/g) on the 9th day in comparison to submerged fermentation (5.1 CVU/g) on the 15th day.

Results revealed that sweet potato peel powder and pea pods provides necessary nutrients required for mycelial growth, and biopigment production, therefore, can be used as potent substrate for biopigment production by Monascus purpureus MTCC 369. Extracted color can be used in confectionery, beverages and pharmaceutical industries.

This work focuses on utilisation of waste for production of pigment as alternative source to synthetic colorant, and few studies have been carried out using wastes, but no work has been carried out on sweet potato peel to the best of the authors’ knowledge.