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To make full use of the tensile strength of near surface mounting (NSM) pasted carbon fiber reinforced plastics (CFRP) strips and further increase the flexural bearing capacity and flexibility of reinforced concrete (RC) beams, a new composite reinforcement method using ultra-high performance concrete (UHPC) layer in the compression zone of RC beams is submitted based on embedding CFRP strips in the tension zone of RC beams. This paper aims to discuss the aforementioned points.

The experimental beam was simulated by ABAQUS, and compared with the experimental results, the validity of the finite element model was verified. On this basis, the reinforced RC beam is used as the control beam, and parameters such as the CFRP strip number, UHPC layer thickness, steel bar ratio and concrete strength are studied through the verified model. In addition, the numerical calculation results of yield strength, ultimate strength, failure deflection and flexibility are also given.

The flexural bearing capacity of RC beams supported by the new method is 132.3% higher than that of unreinforced beams, and 7.8% higher than that of RC beams supported only with CFRP strips. The deflection flexibility coefficient of the new reinforced RC beam is 8.06, which is higher than that of the unreinforced beam and the reinforced concrete beam with only CFRP strips embedded in the tension zone.

In this paper, a new reinforcement method is submitted, and the effects of various parameters on the ultimate bearing capacity and flexibility of reinforced RC beams are analyzed by the finite element numerical simulation. Finally, the effectiveness of the new method is verified by the analytical formula.

The paper aims to introduces an experimental work to investigate the torsional behavior of reinforced concrete (RC) beams strengthened by near-surface mounted (NSM) carbon fiber-reinforced polymer (CFRP) ropes.

In this research, nine rectangular RC beams of 250 mm × 300 mm cross-section and 1,600 mm in length were constructed and tested considering the studied parameters. These parameters include the length of the CFRP rope, the orientation of the CFRP rope, the arrangement of longitudinal and the scheme of NSM-CFRP ropes.

In comparison to control specimens, the results demonstrate a considerable improvement in the torsional response of RC beams strengthened with the CFRP rope. Additionally, specimens strengthened with 90° vertical ropes increase torsional moment capacity more efficiently than specimens strengthened with 45° inclined ropes since the stress concentration leads to premature debonding of the CFRP rope. Whereas RC beams' ability to withstand torsional moments is reduced as the distance between reinforcing CFRP ropes is increased. According to test results, adding CFRP ropes to RC beams' bottoms had a slightly positive impact on torsional response.

This paper fulfills an identified need to study how the using of the CFRP rope is effective in strengthening RC beam subjected to torsion moment.

The main aim of this study is to examine the behavior of reinforced concrete short columns strengthened using longitudinal near surface mounted (NSM)-carbon fiber reinforced polymer (CFRP) strips.

A full 3D-finite element (FE) model was developed using ABAQUS in order to conduct the analysis. The model is first validated based on experimental data available in the literature, and then the effect of concrete compressive strength, number of CFRP strips that are used and the spacing between them were taken in consideration for both concentric and eccentric loading cases. The parametric study specimens were divided into three groups. The first group consisted of unstrengthened columns and served as control specimens. The second group consisted of columns strengthened by longitudinal CFRP strips at two opposite column faces.

The results of this study are used to develop interaction diagrams for CFRP-strengthened short columns and to develop best-fit equations to estimate the nominal axial load and moment capacities for these strengthened columns. The results showed that the specimens that were strengthened using more longitudinal CFRP strips showed a significant increase in axial load capacity and a significant improvement in the interaction diagram, especially at large load eccentricity values. This result can be justified by the fact that longitudinal strips effectively resist the bending moment that is generated due to eccentric loading. Generally, the process of strengthening using longitudinal strips only has a reasonable effect and it can be typically considered an excellent choice considering the economic aspect when the budget of strengthening is limited.

This research aims at studying the performance of strengthened rectangular reinforced concrete short columns with CFRP strips using FE method, developing interaction diagrams of strengthened columns in order to investigate the effect of different parameters such as compressive strength (20, 30 and 40 MPa), number of CFRP strips (1, 2, 3 and 4) and the spacing between CFRP strips in terms of the ratio of CFRP center point distance to column outside dimension ratio (0.60, 0.70 and 0.80) on the behavior of strengthened RC columns and improving empirical formulas to predict the nominal axial load and moment capacities of strengthened RC columns. These parameters that directly affect short column load carrying capacity are presented in ACI-318 (2014).

This paper aims to shed new light on the contextual embeddedness of intersectional entrepreneurs, i.e. entrepreneurs situated at the intersection of multiple marginalized diversity attributes, beyond simply business strategies and decisions. Taking an emic perspective on everyday practices as intersectional entrepreneurs, it uncovers neglected dimensions of the contextuality of intersectional discriminations.

The study presents qualitative data analysis results of in-depth narrative interviews with six intersectional entrepreneurs, all LGBTIQA* entrepreneurs with further diversity dimensions. It provides an emic view of intersectional entrepreneurs, in their everyday lives and the contexts, in which they develop their businesses.

Intersectional entrepreneurs face different burdens induced by social structures along the entrepreneurial process. While access to the niche market is more difficult and they lack community support, their realization of intersectional discrimination is crucial for the development of business strategies. Simultaneously, intersectional entrepreneurs use their specific diversity attributes to develop their business, yet this proximity of their identity and the business contents has severe consequences for their mental state. Intersectional entrepreneurs adjust to the balance of opportunity and vulnerability.

As intersectional entrepreneurs are barred from conventional institutional support and also have limited access to resources from their respective social networks, there is an urgency to provide specific support for such entrepreneurs.

The study explores the nexus between Ibu-Ubu boyhood initiation and the conservation of cultural heritage in Afikpo, Southeast Nigeria. The study is motivated by the rarity of such cultural conservation through initiation rites in an age of Christian-inspired culture terrorism against Igbo traditional religion, arts and relics.

The study adopted cultural anthropological research method. The boyhood initiation rite was studied through participant observation of the initiation between September and November 2017. As a cultural anthropological study, oral evidence was derived from the men who had undergone the rite. Through the oral evidence, interpretations were given to the material culture, monuments and heritage that have been conserved through Ibu-Ubu initiation rite.

The study discovered that amid the deluge of Christian-motivated culture terrorism and erosion of Igbo cultural arts, relics and heritage, the people of Afikpo have preserved most of their tangible and intangible heritage through the Ibu-Ubu boyhood initiation rites.

This study will assist in the reinvigoration of campaigns on environmental and heritage conservation in Igboland. It is sufficient to posit that Igboland is ridden with myriads of environmental and cultural terrorism, perpetrated by some Christian fanatics. The study reveals the relevance of the boyhood initiation rites in ensuring the preservation and conservation of Igbo cultural heritage in a century marked with fanatical Christian evangelism, culture-terrorism and destruction of both tangible and intangible heritages, which the Christians have labelled evil, barbaric and fetish.

The infill design approach for heritage settings is a challenging task, and it draws the attention of design professionals and residents. The extant literature has advocated for a contextual design approach for new buildings in heritage sites. However, the degree of contextualism for a new building in heritage sites is subjective, and it varies between exact replication and contrast scales. This study aims to evaluate an appropriate design approach for historic precincts of Odisha, an eastern state of India.

Two prime eastern heritage sites (Puri and Ekamra Kshetra) are selected as cases in this study. This research methodology involves identifying key architectural elements from both sites and a questionnaire (prepared by design experts) based on interviewing 400 residents and 36 design professionals on their aesthetic preferences for the different architectural styles and elements. The questionnaire was prepared by the design experts based on the identified architectural styles and elements of both sites. Descriptive statistics and correlation analysis are used to measure the significance of design approaches and elements.

This study's outcome confirms that most of the respondents (design professionals and residents) prefer the replication design approach with traditional architectural elements of Odisha. Also, documentation of the chronological development of architectural styles and elements of heritage sites of Odisha is done in this research.

This study has a few limitations: first, the land use characters (mixed, residential, commercial, etc.) of buildings in the heritage precinct are not considered in this research; second, this research has not included the financial aspect of infill design and last, the impact of respondents' socioeconomic factors on their aesthetic perceptions is not considered in this research.

The development authorities can use the outcomes of this research to implement a design strategy for infill buildings in the historical sites of Odisha.

This research article has documented traditional architectural elements of two prime heritage sites of India.

To date, no quantitative research has been done on infill design approaches in any Indian heritage precincts. This is the first quantitative research on the perception of stakeholders and users on the infill design in historical settings of Eastern India. This research has identified key architectural styles, elements and materials of the heritage sites.

The purpose of this study is to investigate the structural, surface roughness and corrosion properties of the zirconium oxide thin films deposited onto SS304 substrates using the direct current (DC) magnetron sputtering technique.

DC sputtering at different powers – 80, 100 and 120 W – was used to deposit ZrO₂ thin films onto different substrates (Si/SS304) without annealing of the substrate. Atomic force microscope (AFM), energy-dispersive X-ray spectroscopy (EDS), Tafel extrapolation and contact angle techniques were applied to investigate the surface roughness, chemical compositions, corrosion behavior and hydrophobicity of these films.

Results showed that the thickness of the deposited film increased with power increase, while the corrosion current decreased with power increase. AFM images indicated that the surface roughness decreased with an increase in DC power. EDS analysis showed that the thin film has a stoichiometric ZrO₂ (Zr:O 1:2) composition with basic uniformity. Water contact angle measurements indicated that the hydrophobicity of the synthesized films decreased with an increase in surface roughness.

DC magnetron sputtering technique is infrequently used to deposition thin films. The obtained thin films showed good hydrophobic and anticorrosion properties. Finally, results are compared with other deposition techniques.

Surface acoustic wave (SAW) sensors have attracted great attention worldwide for a variety of applications in measuring physical, chemical and biological parameters. However, stability has been one of the key issues which have limited their effective commercial applications. To fully understand this challenge of operation stability, this paper aims to systematically review mechanisms, stability issues and future challenges of SAW sensors for various applications.

This review paper starts with different types of SAWs, advantages and disadvantages of different types of SAW sensors and then the stability issues of SAW sensors. Subsequently, recent efforts made by researchers for improving working stability of SAW sensors are reviewed. Finally, it discusses the existing challenges and future prospects of SAW sensors in the rapidly growing Internet of Things-enabled application market.

A large number of scientific articles related to SAW technologies were found, and a number of opportunities for future researchers were identified. Over the past 20 years, SAW-related research has gained a growing interest of researchers. SAW sensors have attracted more and more researchers worldwide over the years, but the research topics of SAW sensor stability only own an extremely poor percentage in the total researc topics of SAWs or SAW sensors.

Although SAW sensors have been attracting researchers worldwide for decades, researchers mainly focused on the new materials and design strategies for SAW sensors to achieve good sensitivity and selectivity, and little work can be found on the stability issues of SAW sensors, which are so important for SAW sensor industries and one of the key factors to be mature products. Therefore, this paper systematically reviewed the SAW sensors from their fundamental mechanisms to stability issues and indicated their future challenges for various applications.

The purpose of this study is to evaluate the efficiency of a Brazilian steelmaking company’s reheating process of the hot rolling mill.

The research method is a quantitative modeling. The main research techniques are data envelopment analysis, TOBIT regression and simulation supported by artificial neural networks. The model’s input and output variables consist of the average billet weight, number of billets processed in a batch, gas consumption, thermal efficiency, backlog and production yield within a specific period. The analysis spans 20 months.

The key findings include an average current efficiency of 81%, identification of influential variables (average billet weight, billet count and gas consumption) and simulated analysis. Among the simulated scenarios, the most promising achieved an average efficiency of 95% through increased equipment availability and billet size.

Additional favorable simulated scenarios entail the utilization of higher pre-reheating temperatures for cold billets, representing a large amount of savings in gas consumption and a reduction in CO2 emissions.

This study’s primary innovation lies in providing steelmaking practitioners with a systematic approach to evaluating and enhancing the efficiency of reheating processes.

The weld joint mechanical properties of friction stir welding (FSW) are majorly reliant on different input parameters of the FSW machine. The study and optmization of these parameters is uttermost requirement and aim of this study to increase the suitability of FSW in different manufacturing industries. Hence, the input parameters are optimized through different soft computing methods to increase the considered objective in this study.

In this research, ultimate tensile strength (UTS), yield strength (YS) and elongation (EL) of FSW prepared butt joints of AA6061 and AA5083 Aluminium alloys materials are investigated as per American Society for Testing and Materials (ASTM E8-M04) standard. The FSW joints were prepared by changing the three input process parameters. To develop experimental run order design matrix, rotatable central composite design strategy was used. Furthermore, genetic algorithm (GA) in combination (Hybrid) with response surface methodology (RSM), artificial neural network (ANN), i.e. RSM-GA, ANN-GA, is exercised to optimize the considered process parameters.

The maximum value of UTS, YS and EL of test specimens on universal testing machine was measured as 264 MPa, 204 MPa and 14.41%, respectively. The most optimized results (UTS = 269.544 MPa, YS = 211.121 MPa and EL = 17.127%) are obtained with ANN-GA for the considered objectives.

The optimization of input parameters to increase the output objective values using hybrid soft computing techniques is unique in this research paper. The outcomes of this study will help the FSW using manufacturing industries to choose the best optimized parameters set for FSW prepared butt joint with improved mechanical properties.