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Owing to a high amount of stress, seam failure in workwear fabrics makes the fabric unsuitable although the fabric strength is high. It is therefore important to predict the seam strength to ascertain the performance of the garments during use and determine the required thread strength and stitch density to match the required seam strength. In all of the earlier predictive equations, seam strength is predicted from thread strength and stitch density along with some multiplicative factors. During the sewing process, a substantial loss in needle thread strength occurs; therefore, the thread becomes weaker than expected after incorporation into the seam. In this paper, the effects of various machine and process parameters are studied on thread strength loss and seam strength. The seam strength is predicted from the loop strength after considering the loss in thread strength. It is observed that higher seam strengths are observed when stronger threads are used for sewing. Loss in thread strength has a significant influence on the seam strength. Seam strength can be predicted using stitch density and thread loop strength, by considering the loss in thread strength during the sewing process. A closer match between predicted and experimental seam strength is possible.

This paper aims to offer a roadmap for a strengths-based approach to leadership.

A review and synthesis of various concepts relating to strengths in the workplace.

A strengths-based approach to leadership can lead to many positive outcomes, including increased employee engagement, productivity, satisfaction, performance and a more positive work environment.

This is a synthesis of a variety of ideas about how to lead with strengths and the positive implications of a strengths-oriented workplace culture.

Evidence has indicated plausible effects of employees' use of their personal strengths at work on their attitudes, performance and well-being. Although the use of personal strengths was also expected to benefit others in the organization, such effects have rarely been examined. Here we studied associations of principals’ use of their personal strengths with principals’ own engagement and with the strengths use and engagement of teachers under their supervision, anticipating that principals’ and teachers’ strengths use and engagement would be associated with students’ achievement.

We surveyed 92 Israeli principals and 474 of their teachers. Measures included self-reported strengths use and engagement of the participants’ and schools' student matriculation achievements.

The findings generally supported the hypotheses. HLM analyses indicated that principals' use of their personal strengths was associated with their own engagement and with teachers' strengths use and work engagement and teachers’ engagement (but not their strengths use) was associated with student achievement.

These findings suggest the beneficial impact of principals' use of their personal strengths on teachers, with practical implications for fostering principals’ and teachers’ flourishing and creating and supporting humanizing schools, by building on principals’ and teachers’ strengths and fostering their use at work.

This is the first study about the potential effects of principals’ strengths use on their own engagement and on others in the school. The significant associations found propose a promising path forward for principals’ positive impact on teachers and students.

The research investigates the impact of concrete design methods on performance, emphasizing environmental sustainability. The study compares the modified Bolomey method and Abrams’ law in designing concretes. Significant differences in cement consumption and subsequent CO2 emissions are revealed. The research advocates for a comprehensive life cycle assessment, considering factors like compressive strength, carbonation resistance, CO2 emissions, and cost. The analysis underscores the importance of evaluating concrete not solely based on strength but also environmental impact. The study concludes that a multicriteria approach, considering the entire life cycle, is essential for sustainable concrete design, addressing durability, environmental concerns, and economic factors.

The study employed a comprehensive design and methodology approach, involving the formulation and testing of 20 mixed concretes with strengths ranging from 25 MPa to 45 MPa. Two distinct design methods, the modified Bolomey method (three equations method) and Abrams’ law, were utilized to calculate concrete compositions. Laboratory experiments were conducted to validate the computational models, and subsequent analyses focused on assessing differences in cement consumption, compressive strength, CO2 emissions, and concrete resistance to carbonation. The research adopted a multidisciplinary perspective, integrating theoretical analysis, laboratory testing, and life cycle assessment to evaluate concrete performance and sustainability.

Conclusion from the study includes substantial variations (56%–112%) in cement content, depending on the calculation method. Abrams' law proves optimal for compressive strength (30 MPa–45 MPa), while the three equations method yields higher actual strength (30%–51%). Abrams' law demonstrates optimal cement use, but concrete designed with the three equations method exhibits superior resistance to aggressive environments. Cement content exceeding 450 kg/m³ is undesirable. Concrete designed with Abrams' law is economically favorable (12%–30% lower costs). The three equations method results in higher CO2 emissions (38–83%), emphasizing the need for life cycle assessment.

This study’s originality lies in its holistic evaluation of concrete design methods, considering environmental impact, compressive strength, and cost across a comprehensive life cycle. The comparison of the traditional Abrams' law and the three equations method, along with detailed laboratory tests, contributes novel insights into optimal cement use and concrete performance. The findings underscore the importance of a multicriteria approach, emphasizing sustainability and economic viability. The research provides valuable guidance for engineers and policymakers seeking environmentally conscious and economically efficient concrete design strategies, addressing a critical gap in the field of construction materials and contributing to sustainable infrastructure development.

Present work deals with the partial substitution of cement by waste demolished concrete powder (WDP) for reducing the carbon footprints of concrete.

Control specimens and the specimens with 20% WDP as fractional substitute of cement were prepared. The waste powder was thermally activated at 825 °C prior to its use in the mix. The prepared specimens were evaluated in terms of density, workability, mechanical strength, Ultrasonic pulse velocity (UPV) and rebound hammer (RH).

The results showed that with the substitution, the workability of the mix increased, while the density decreased. A decrement within a 20% limit was found in compressive strength. The UPV and RH results were closely linked to the other results as mentioned above.

The study deals with only M15 concrete and the substitution level of only 20% as a baseline.

The concrete containing 20% WDP is lightweight and more workable. Moreover, its strength at 28 days is 14 MPa, only 1 MPa lesser than the characteristic strength.

The WDP can be recycled and the dumping in landfills can be reduced. This is an important effort towards the decarbonation of concrete.

Previous literature indicates that the WDP has been frequently used as a partial replacement of aggregates. However, some traces of secondary hydration were also reported. This work considers the effect of partial substitution of cement by the WDP.

This paper aims to focus on the reliability of Sn15Bi–xAg and Sn15Bi–xCu solder joints during isothermal aging.

The effects of Ag or Cu additions on the microstructure, interfacial metallic compound layer and shear strength of Sn–15Bi (Sn15Bi) based solder joints during were investigated. The effects of Ag or Cu additions on the microstructure and tensile properties of Sn15Bi-based bulk solders were also investigated to provide a comprehensive analysis. The interfacial morphology and microstructure were observed by scanning electron microscopy and the composition in the structure was examined by energy dispersive spectrometer. The shear tests were carried out on the as-soldered and as-aged joints using a ball shear tester.

The results revealed that by adding Ag or Cu, the microstructure of Sn15Bi solder can be refined. Ag addition increased the tensile strength of Sn15Bi solder but had little effect on elongation. However, Cu addition decreased the tensile strength and elongation of Sn15Bi solder. For solder joints, Ag addition increased the shear strength and toughness of Sn15Bi/Cu joints but Cu addition decreased the shear strength and toughness of Sn15Bi/Cu joints.

The authors can potentially provide a replacement for Sn40Pb traditional solder with Sn15Bi solder by alloying Ag or Cu due to its lower cost and similar melting point as Sn–Pb solder.

Low-carbon concrete represents a new direction in mitigating the global warming effects caused by clinker manufacturing. Utilizing Saudi agro-industrial by-products as an alternative to cement is a key support in reducing clinker production and promoting innovation in infrastructure and circular economy concepts, toward decarbonization in the construction industry. The use of fly ash (FA) as a cement alternative has been researched and proven effective in enhancing the durability of FA-based concrete, especially at lower replacement levels. However, at higher replacement levels, a noticeable impediment in mechanical strength indicators limits the use of this material.

In this study, low-carbon concrete mixes were designed by replacing 50% of the cement with FA. Varying ratios of nano-sized glass powder (4 and 6% of cement weight) were used as nanomaterial additives to enhance the mechanical properties and durability of the designed concrete. In addition, a 10% of the mixing water was replaced with EMs dosage.

The results obtained showed a significant positive impact on resistance and durability properties when replacing 10% of the mixing water with effective microorganisms (EMs) broth and incorporating nanomaterial additives. The optimal mix ratios were those designed with 10% EMs and 4–6% nano-sized glass powder additives. However, it can be concluded that advancements in eco-friendly concrete additive technologies have made significant contributions to the development of sophisticated concrete varieties.

This study focused at developing nanomaterial additives from Saudi industrial wastes and at presenting a cost-effective and feasible solution for enhancing the properties of FA-based concrete. It has also been found that the inclusion of EMs contributes effectively to enhancing the concrete's resistance properties.

Although strengths use support (SUS) has been shown to facilitate employee strengths use and work engagement, little is known about how senior managers’ SUS affects middle managers’ SUS. The purpose of the present research was to examine the trickle-down effect of SUS from superiors on SUS for subordinates.

A two-wave questionnaire survey was conducted to collect data from middle managers (n = 228) at a global manufacturing firm in Japan.

The results of structural equation modeling indicated that (1) SUS from superiors indirectly promoted SUS for subordinates mediated through middle managers’ strength use, and (2) SUS from superiors indirectly promoted SUS for subordinates mediated through middle managers’ strength use, and subsequently through their work engagement.

As the respondents were middle-level managers at a manufacturing firm in Japan and were all Japanese nationals, indigenous culture and traditional work mentality may have affected the results.

To create a supportive learning culture in an organization, human resource (HR) managers need to encourage senior-level managers to provide SUS for middle managers through HR systems such as training, appraisal, and survey feedback.

This study may be the first to clarify how SUS from superiors is linked to SUS for subordinates by identifying the mediating effects of strength use and work engagement, based on the Job-Demand Resources model, the Social Cognitive theory, and the trickle-down effect.

The main aim of the current study is to investigate the effect of Anti-Crack HP 67/36 glass fibre on the mechanical performance of mortars made of cement, with a focus on post-cracking evaluations using the digital image correlation (DIC) technique.

Experimental tests were carried out on 36-mm long fibres at 0.8% by volume and added to the normal strength (NSM), high strength (HSM) and high strength mortar with fly ash (HSMFA) mortars. CEM I 52.5 CP2 NF, CEM II/A-L 42.5 NF and CEM III/C 32.5 N-SR PM were used for each series of mortar to assess the performance of the glass fibres with the types of cement. F-class fly (FA) ash was used to reduce global CO₂ emissions.

The mortar’s strength decreased as the cement types changed from CEM I to CEM II and III. However, due to changes in the portlandite content of the cement, water porosity increased for both types of mortar, without and with fibre. It was also found that using glass fibre increased flexural strength more than compressive strength, regardless of the type of cement used. For all the strength classes, it was found that the mortar mixes with CEM I had the highest critical crack opening (w_c) and fracture energy (G_F), followed by CEM II and III. No significant effects were observed in the mortar’s property by replacing fly ash (12%).

Only mortars were formulated in this study, but the results must be verified at the concrete scale.

Validation of the DIC technique to characterize the post-cracking behaviour of cement-based material. Use of glass fibres to improve the material’s resistance to cracking.

Use of CEM II and CEM III cements with low CO₂ footprint instead of CEMI without altering the mechanical performance of the material.

The work is a further contribution to studying the cracking behaviour of several series of variable mortars depending on the resistance class and the type of cement used.

The purpose of this study was to examine how well a strength-based program grounded in positive psychology principles can advance the practical critical thinking skills of those pursuing the teacher training course.

This study used a single-group pre-test post-test design with 35 teacher-trainees from the Bachelor of Education course. The two-and-a-half-week strength-based program used the values in action survey to identify strengths. Pre- and post-test scores, measured with the Cornell Critical Thinking Test – Level Z, underwent Statistical Package for Social Sciences analysis including paired samples t-test for subcomponent and overall composite analysis.

Analysis of the pre- and post-test scores demonstrated a statistical significance in the critical thinking scores obtained by the teacher-trainees. Post-test scores were consistently significant. Out of the elements of critical thinking, induction, meaning, observation and credibility were more prominent. Deduction and assumption identification were also having a significant effect.

Most critical thinking programs focus on evaluating specific teaching methods for improving critical thinking skills. In education, positive psychology studies often center on students’ well-being, attention spans and academic success, aligning with wellness programs. Despite the importance of strengths in positive psychology, there is a lack of research on using a strength-based approach to boost critical thinking skills. This study aims to enhance teacher-trainees’ critical thinking by leveraging their individual strengths, moving away from traditional instructional strategies.