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The purpose of this paper is to make a contribution to understanding the influence of factors such as the water/cement (W/C) ratio and the granular class on the mechanical and physical properties of high-strength concretes (HSCs). In the formulations of HSC, aggregates by their high mass and volume proportion play an important role. When selecting aggregates, it is necessary to know their intrinsic properties. These properties influence the performance of concrete, in particular the quality of the granulate cimentary adhesion.

This experimental study focused on the effect of W/C ratio (0.25, 0.30, 0.35), the effect of replacing a part of cement by silica fume (SF) (8%), the effect of fraction of aggregate on properties of fresh and hardened concrete, the effect of different environment conversation like drinking water and sea water on compressive strength and the study of absorption of water and softening using the mix design method of the University of Sherbrooke combined with the Dreux-Gorisse method which gives good results.

At the end of our work, the examination of the results obtained made it possible to establish the correlations between the formulations studied and the physicomechanical characteristics of the concrete compositions (HSC25, HSC16, HSC8). The results of this study show that the use of three granular classifications (DMAX8, DMAX16 and DMAX25) and three report W/C (0.25, 0.30 and 0.35) in two different conservation environment (drinking water and sea water) give HSCs, HSC25 with an W/C = 0.25 ratio has reached the largest mechanical strength of 90 MPa for different environments of conservation. For selecting aggregates, it is necessary to know their intrinsic properties, these properties influence the strength of concrete. In general, there is a slight decrease in the compressive resistance of the specimens stored in seawater, it can be said that the conservation life has not had effect on the resistance (28 days). The effect of aggressive environment can appear in the long term.

Mixed design and concrete fabrication with a 28-day compressive strength of up to 68 MPa or more of 90 MPa can now be possible used in Jiel (Algeria), and it should no longer be considered to be used only in an experimental domain. Addition of SF in concrete showed good development of strength between 7 and 28 days, depending on the design of the mix.

Concrete containing 8% SF with W/B of 0.25 has higher compressive strength than the other concretes, and concretes with SF are more resistant than concretes without SF, so it is possible to have concrete with a compressive strength of 82 MPa for W/C 0.25 without SF. Like as a result, we can avoid the use of SF to affect the strength of concrete at compressive strength of 68 MPa, and a slump of 21 cm, because the SF is the most expensive ingredient used in the composition of concrete and is therefore very important economically. One of the main factors of production of HSC above 90 MPa is use of aggregate DMAX25, which is stronger with W/B of 0.25 and 0.30.

This mixtures leads to a very dense microstructure and low porosity and produces increased permeability of HSC and is able to resist the penetration of aggressive agents. This combination has a positive effect on the economy of concrete.

The combination of the Dreux-Gorisse method with the Sherbrook method is very beneficial for determining the percentage of aggregates used, and the use of coarse aggregates of Jijel to obtain HSC with 90 MPa and 16 cm of workability.

The twenty-first century is noted globally as the urban century because more than half of the world's population lives in cities. This population is projected to increase to 70% by 2050. South Africa is no exception to this phenomenal increase in urban population. More than 60% of South African population lives in urban areas, and this figure is projected to increase to 71.3% and 80% by 2030 and 2050, respectively. Access to human settlement by this teaming population remains a challenge. The problem of access to human settlement is compounded by historical apartheid's spatial geography characterized by racial segregation, fragmentation of urban space and separate development. During the apartheid period, settlement patterns were designed and planned in accordance with racial differentiation. This resulted in fragmented, segregated and dysfunctional residential settlements pattern that forced many people to travel long distances between place of work and home. Since 1994, the various housing policies, programmes and legislations have not been able to find solution to the spatial challenges that South Africa faces. The objective of this book is to investigate and unravel mixed-income housing development planning strategy and how this housing typology with a new framework can bring about spatial integration, inclusive cities, improved access to services and the promotion of social cohesion and economic inclusion. This book utilized the case study research design and employed the Delphi method for the investigation. The findings reveal that proper coordination across all sectors of government and good working relationship between the private and public sectors will increase the sustainability of mixed-income housing development. This study also supports existing theory that mixed-income housing might not be able to bring about the overall social integration, and solve all housing problems but has the unique tendency and potential in the South African case to address spatial imbalances by increasing the affordability of low-cost housing. This book concludes that there is need for both inter-sectoral and intergovernmental collaboration as well as proper coordination/adequate urban planning policies to address the increasing human settlement challenges in South Africa and for effective implementation of mixed-income housing development.

We theorize the critical role of angel investors' affective experiences and first impressions in the context of entrepreneurial finance. We develop a model and propositions to illustrate why angel investors make the decision to continue screening, thus explaining why certain investment proposals make it, while others do not.

Drawing on affective events theory and the literature on affective experiences, we theorize how the perceptions of pitches that trigger positive or/and negative physiological arousal, short-lived emotions, and associated thoughts are different, thus allowing us to build new theory of how these different experiences can influence the outcome of the evaluation process in the initial screening stage.

Our model suggests that the initial evaluation unfolds in five stages: perception of an entrepreneurial pitch, physiological arousal, emotions, first impression, and a decision to continue screening. When different manifestations of physiological arousal and subsequent emotions set the tone of first impressions, they can be either a positive, negative, or mixed experience. While positive and mixed first impression can lead to selection, negative first impression can lead to rejection.

We illustrate what is of value for angel investors when they look for new investments, and why certain entrepreneurial pitches lead to the decision to continue screening, while others do not. We propose that what angel investors feel is particularly important in situations where they are not yet making the ultimate decision to invest money but are involved in decisions about whether to continue to spend time to investigate the investment proposal.

This study examines the role of psychological safety as an antecedent to meaningful work and as a mediator between transformational leadership (TFL) and meaningful work. Additionally, it explores customer incivility as a precursor to psychological safety and as a moderator in the relationship between psychological safety and meaningful work.

Data from 368 hotel employees in Bangladesh were purposively sampled and analyzed using SmartPLS.

Psychological safety positively predicted meaningful work and served as a mediator in the nexus between TFL and meaningful work. Additionally, customer incivility was identified as a negative predictor of safety and acted as a moderator, reversing the association between psychological safety and meaningful work.

TFL exhibits mixed correlations, being negatively associated with meaningful work but positively linked to psychological safety. Therefore, workplaces should prioritize cultivating a psychologically safe environment and minimizing customer incivility to increase meaningful work.

The results add value to the conservation of resources and self-concept theories by examining the mediating role of psychological safety and the moderating influence of customer incivility from the perspective of hotel employees.

This study aims to investigate whether higher value creation leads to higher value appropriation and to identify the boundary conditions in a buyer–supplier relationship that can explain why a particular supplier can appropriate higher value than others.

The study uses questionnaire surveys. The sample of the survey has 150 publicly-listed supplier firms in Taiwan. The unit of analysis is the buyer–supplier relationship.

In the buyer–supplier relationship, suppliers’ bargaining power, partnership and a supplier’s original brand manufacturing (OBM) business can strengthen the positive relationship between value creation and value appropriation.

This study adopts the unilateral viewpoint of suppliers; however, some constructs might require dyadic evaluation. This study only explores the spillover effect of OBM business on the relationship between value creation and appropriation.

The spillover effect of a supplier’s OBM business in a buyer–supplier relationship allows the buyer to share more common benefits and the supplier to capture more private benefits as compensation. By broadening its customer base, a supplier can increase its bargaining power. A supplier can also maintain a strategic partnership with each essential buyer.

To avoid the dark-side effect of partnership, the model provides the contingency that a supplier can capture more value from a buyer–supplier relationship.

Corporate real estate management (CREM) is complex due to an increasing number of real estate (RE) added values and the tensions between them. RE managers are faced with trade-offs: to choose a higher performance for one added value at the cost of another. CREM research mainly deals with trade-offs in a hypothetical sense, without looking at the characteristics of the RE portfolio nor the specific context in which trade-offs are made. The purpose of this paper is to further develop the concept of real estate value (REV) optimisation with regard to tensions between decreasing CO₂ emissions and supporting user activities.

Mixed method study. REV optimisation between user activities and energy efficiency for police stations in the Netherlands built between 2000 and 2020 is analysed. This is complemented by interviews with an RE manager and senior user of police stations and analysis of policy documents.

The characteristics of the police station portfolio indicate no correlation between user activities and energy efficiency for the case studied. This is complemented by interviews, from which it becomes clear that there was in fact little tension between supporting user activities and energy efficiency. The performances of these two different added values were optimised separately.

This study combines different scales (building and portfolio level) with different types of data: portfolio analysis, document analysis and interviews. This creates a comprehensive image of whether and how the Netherlands police optimised the two RE values.

The scope of this work is to explore whether Regional Comprehensive Economic Partnership (RCEP) would be beneficial to Bangladesh, given Bangladesh's strong ties with India and the west.

Using extended gravity equation and data from Head and Mayer (2021) and the Direction of Trade Statistic (IMF, 2021) for Bangladesh with its applicable partner countries from 1972 till 2019, the authors attempted to examine the potential impact of joining RCEP while keeping its relationship with South Asian Association for Regional Cooperation (SAARC), and other existing economic integration schemes intact.

Using traditional pooled ordinary least squares, two-stage least square and generalized method of moment techniques, it has been revealed that conventional partners in the South led by India are still beneficial to Bangladeshs trading line. Joining RCEP provides ample avenues for trade expansion without replacing the positive effects of SAARC.

Traditional partners from European, American and South Asian trading opportunities are still paying enough dividends to Bangladesh. RCEP is providing a trade-enhancing chance for Bangladesh in the eastern direction. This paper provides a policy suggestion to look east policy of government. A total overhaul of her tax structure through minimizing excessive reliance on import tariff revenue is desired to facilitate her to join RCEP in the future because most of its prospective RCEP partners are import partners.

This is the first and the only study which explores the feasibility of Bangladesh to join the RCEP by using the most recently updated gravity data in a panel framework.

1. Since its inception on November 15, 2020, Regional Comprehensive Economic Partnership (RCEP) has emerged as one of the largest economic integration areas in the world.

2. As a borderline country between South Asia and RCEP, Bangladesh is in a fix to take a decision either to join or not to join RCEP if they are invited.

3. This paper used the gravity equation in an extended form by taking Bangladesh with its 197 trading partners’ trade data for 1972–2019.

4. The findings postulate that the existing relationship with SAARC countries is still beneficial to its welfare, and RCEP is also economically helpful in enhancing its trade.

Since its inception on November 15, 2020, Regional Comprehensive Economic Partnership (RCEP) has emerged as one of the largest economic integration areas in the world.

As a borderline country between South Asia and RCEP, Bangladesh is in a fix to take a decision either to join or not to join RCEP if they are invited.

This paper used the gravity equation in an extended form by taking Bangladesh with its 197 trading partners’ trade data for 1972–2019.

The findings postulate that the existing relationship with SAARC countries is still beneficial to its welfare, and RCEP is also economically helpful in enhancing its trade.