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The purpose of this paper is to numerically investigate the convective heat transfer of water-based CuO nanofluids flowing through a square cross-section duct under constant heat flux in the turbulent flow regime.

The numerical simulation is carried out at various Peclet numbers and particle concentrations (0.1, 0.2, 0.5, and 0.8 vol%). The finite volume formulation is used with the semi-implicit method for pressure-linked equations algorithm to solve the discretized equations derived from the partial nonlinear differential equations of the mathematical model.

The heat transfer coefficients and Nusselt numbers of CuO-water nanofluids increase with increases in the Peclet number as well as particle volume concentration. Also, enhancement of the heat transfer coefficient is much greater than that of the effective thermal conductivity at the same nanoparticle concentration.

Simulation of nanofluids turbulent forced convection at very high Reynolds number is worth for further study.

The heat transfer rates through non-circular ducts are smaller than the circular tubes. Nevertheless, the pressure drop of the non-circular duct is less than that of the circular tube. This study clearly presents that the nanoparticles suspended in water enhance the convective heat transfer coefficient, despite low volume fraction between 0.1 and 0.8 percent. Adding nanoparticles to conventional fluids may enhance heat transfer performance through the non-circular ducts, leading to extensive practical applications in industries for the non-circular ducts.

Few papers have numerically studied convective heat transfer properties of nanofluids through non-circular ducts. The present numerical results show a good agreement with the published experimental data.

This paper aims to determine the level of awareness and implementation of family‐responsible parameters: policies, enablers, practices, and culture, in Spanish and Latin‐American companies, and how they impact work‐life balance.

The study uses data from different national IESE's Family‐Responsible Employer Index surveys in Spain (1,000 companies) and five Latin‐American countries (1,155 companies), Brazil, Chile, Colombia, El Salvador and Peru, done between 2006 and 2008. This is a structured questionnaire that assesses the stage of development the organization is in regarding four main family‐responsible parameters: policies, enablers, practices, and culture.

Latin‐American countries get a slightly higher number of companies that are fully supportive of work‐family balance environment than Spain, but with lesser formal policies implemented and a stronger presence of enablers and practices. Policies are important but might not be as effective if not accompanied by the example of managers and staff as well as by a deep understanding of the cultural value placed by them on work, family and personal life.

The survey‐based data used limits insight into causal relationships. Qualitative and longitudinal studies are needed in order to clarify motives for individual and organizational decisions regarding work‐life initiatives. Data collected are from one source only: employer's management. Multi‐source studies must follow and include the public sector.

This is the first comparison between Spanish companies and companies from five Latin‐American countries regarding work‐family policies, enablers, practices and culture with such an ample number of companies. Findings will aid HRD practitioners in developing work‐family initiatives and help researchers to address new questions in cross‐cultural comparisons.

China's controversial one-child policy has been blamed for creating an ageing population, a generation of employees without siblings and a 4-2-1 family structure that places eldercare responsibility, primarily on women. Current understanding of how this affects contemporary employees' work–life interface is lacking. This study examined the moderating roles of family structure and gender in the relationships between work–life conflict (WLC), job satisfaction and career aspiration for university academics.

Online and self-administered surveys were used to collect data, which involved 420 academic staff in three Chinese research universities.

Our results revealed that WLC is positively related to career aspiration, and this relationship is stronger for academics with siblings and, within the only-children group, significantly stronger for women than for men. WLC is also negatively related to job satisfaction, and this relationship is stronger for only-children academics.

Results were limited by a cross-sectional sample of modest size. Nevertheless, this study contributes to the understanding of gender roles and changing family structure in the work–life interface of Chinese academics.

Our findings have implications for both universities seeking to improve staff well-being and for wider society. A number of support mechanisms are proposed to enhance the ability of only children, especially women, to operate as effective members of the labour market.

Our results showed that only-children academics face a unique set of difficulties across career and family domains, which have been previously neglected in literature.

Multi-well hydrofracturing is an important technology to create new fractures and expand existing fractures to increase reservoir permeability. The propagation morphology of the fracture network is affected by the disturbance between the fractures initiation sequences and spacings between adjacent wells. However, it remains unclear how well spacing and initiation sequences lead to fracture propagation, deflection and connection.

In this study, the thermal-hydro-mechanical coupling effect in the hydrofracturing process was considered, to establish a finite element-discrete element model of multistage hydrofracturing in a horizontal well. Using typical cases, the unstable propagation of hydraulic fractures in multiple horizontal wells was investigated under varying well spacing and initiation sequences. Combined with the shear stress shadow caused by in situ stress disturbed by fracture tip propagation, the quantitative indexes of fracture propagation such as length, volume, displacement vector, deflection and unstable propagation behavior of the hydrofracturing fracture network were analyzed.

The results show that the shear stress disturbance caused by multiple hydraulic fractures is a significant factor in multi-well hydrofracturing. Reducing the spacing between multiple wells increases the stress shadow area and aggravates the mutual disturbance and deflection between the fractures. The quantitative analysis results show that a decrease of well spacing reduces the total length of hydraulic fractures but increases the total volume of the fracture; compared with sequential and simultaneous fracturing, alternate fracturing can effectively reduce stress shadow area, alleviate fracture disturbance and generate larger fracture propagation length and volume.

The numerical models and results of the unstable propagation and stress evolution of the hydraulic fracture network under thermal-hydro-mechanical coupling obtained in this study can provide useful guidance for the evaluation and design of rock mass fracture networks in deep unconventional oil and gas reservoirs.

Since 2014, “sport for all” has been promoted as a new national strategy in China, which injects powerful dynamism and vitality for its development in numerous aspects. However, there has been very little feedback on sport service provision in community, and the satisfaction level of community participants is largely unmeasured. To promote physical and mental health of residents and form a stronger foundation of sport culture, more attention should be directed to community sports. The purpose of this paper is to examine the impact of community-sport service provisions on participants’ satisfaction and, in turn, on their sport participation behavior.

Community-sport program participants in China (n=576) responded to a survey measuring the proposed concepts.

Structural equation modeling analyses revealed that community-sport services in the areas of sport facility, grassroots sport organizations and sport activity programs had strong influences on participant satisfaction and, in turn, their desire for participation, which highlighted the demand for high-quality sport service provision by community.

The study contributed to the literature by proposing two clear dimensions (core sport service and peripheral sport service) for the measurement of public sport service provision in community sports. A second theoretical contribution of the study relates to the clarification of the relationship between the two dimensions of community-sport service provision (both core and peripheral services) and community participants’ satisfaction levels.

The purpose of this paper is to examine the mediating role of work atmosphere which have a positive influence on job satisfaction. Specifically, it focuses on how supervisor’s cooperation and career growth affect job satisfaction mediating through work atmosphere in a private corporate entity.

To attain this objective, a research framework with a mediating variable of work atmosphere was formulated. Using measurement scales created to assess different aspects of job satisfaction, career growth, supervisor’s cooperation and work atmosphere, a survey instrument was developed to test the various relationships implied by the framework. Data (n = 325) were collected from the employees of a local chemical company in Bangladesh following convenience sampling procedure. The analysis has been done by bootstrapping procedure following structural equation modeling (SEM).

The result shows that work atmosphere has a significant mediating role in linking supervisor cooperation and job satisfaction of the employees in the organization.

As with any study, there are limitations to the study described here. One possible drawback is the use of a single company’s employees as respondents. Second, the sample size is not very large, because respondents were observed to be negligent in filling the questionnaire provided to them. If the sample size could be increased a bit more, then the authors might have better outcomes as postulated in the paper. Nevertheless, the usual cautions about over-generalizing findings from this sample, to populations for which it is not strictly representative, apply. The sample was not randomly drawn to represent a population to which findings could be generalized. Instead, it was a convenience sample, and as such, the ability to generalize the findings very far beyond the sample is limited.

From a practical perspective, as a cumulative body of work on job satisfaction with mediating variable of work atmosphere emerges, the authors will be better able to advise employers on the elements they need to address to increase their employee retention rate. In this study, the one area of findings that may help business and commercial organizations the most concerns work environment in the workplace. The authors found that supervisor cooperation and work atmosphere were associated with positive path value toward job satisfaction. Similarly, career growth and work atmosphere also exhibit positive path value towards job satisfaction. The implication is that employers can focus on supervisor cooperation in rightly and duly promoting the deserving employees, and in doing so, they can generate positive attitudes toward these activities.

This paper will add immense importance of work atmosphere to the organizational learning and behavior.

Hydrofracturing technology has been widely used in tight oil and gas reservoir exploitation, and the fracture network formed by fracturing is crucial to determining the resources recovery rate. Due to the complexity of fracture network induced by the random morphology and type of fluid-driven fractures, controlling and optimising its mechanisms is challenging. This paper aims to study the types of multiscale mode I/II fractures, the fluid-driven propagation of multiscale tensile and shear fractures need to be studied.

A dual bilinear cohesive zone model (CZM) based on energy evolution was introduced to detect the initiation and propagation of fluid-driven tensile and shear fractures. The model overcomes the limitations of classical linear fracture mechanics, such as the stress singularity at the fracture tip, and considers the important role of fracture surface behaviour in the shear activation. The bilinear cohesive criterion based on the energy evolution criterion can reflect the formation mechanism of complex fracture networks objectively and accurately. Considering the hydro-mechanical (HM) coupling and leak-off effects, the combined finite element-discrete element-finite volume approach was introduced and implemented successfully, and the results showed that the models considering HM coupling and leak-off effects could form a more complex fracture network. The multiscale (laboratory- and engineering-scale) Mode I/II fractures can be simulated in hydrofracturing process.

Based on the proposed method, the accuracy and applicability of the algorithm were verified by comparing the analytical solution of KGD and PKN models. The effects of different in situ stresses and flow rates on the dynamic propagation of hydraulic fractures at laboratory and engineering scales were investigated. when the ratio of in situ stress is small, the fracture propagation direction is not affected, and the fracture morphology is a cross-type fracture. When the ratio of in situ stress is relatively large, the propagation direction of the fracture is affected by the maximum in situ stress, and it is more inclined to propagate along the direction of the maximum in situ stress, forming double wing-type fractures. Hydrofracturing tensile and shear fractures were identified, and the distribution and number of each type were obtained. There are fewer hydraulic shear fractures than tensile fractures, and shear fractures appear in the initial stage of fracture propagation and then propagate and distribute around the perforation.

The proposed dual bilinear CZM is effective for simulating the types of Mode I/II fractures and seizing the fluid-driven propagation of multiscale tensile and shear fractures. Practical fracturing process involves the multi-type and multiscale fluid-driven fracture propagation. This study introduces general fluid-driven fracture propagation, which can be extended to the fracture propagation analysis of potential fluid fracturing, such as other liquids or supercritical gases.

Multi-well hydrofracturing is a key technology in engineering, and the evaluation, control and optimization of the fracturing network determine the recovery rate of unconventional oil and gas production. In engineering terms, altering well spacing and perforation initiation sequences changes fracture propagation behavior. Fracture propagation can result in fracture-to-fracture and well-to-well interactions. This may be attributed to the interference between fractures caused by squeezing of the reservoir strata. Meanwhile, the stratal movement caused by the propagation of the fractures may lead to either the secondary fracturing of wells with primary fractures or perforation to begin fracturing. Besides, the stratal compression and squeeze of multi-well hydrofracturing will cause earthquakes; the fracture size is different owing to the different fracturing scenarios, and the occurrence of induced microseismic events is still unknown; microseismic events also affect fracture orientation and deflection. If the mechanism of the above mechanical behavior cannot be clarified, optimizing the fracture network and reduce the induced microseismic disaster becomes difficult.

In this study, combined finite element-discrete element models were used to simulate the multi-well hydrofracturing. Numerical cases compared the fracture network, dynamic stratal movement and microseismic events at 50, 75 and 100 m well spacings, respectively, and varying initiation sequence of multiple horizontal wells.

From the results, fracture propagation in multi-well hydrofracturing may simulate the propagation and deflection of adjacent fractures and induce fracture-to-fracture and well-to-well interactions. As the well spacing increases, the effect of fracturing-induced stratal movement and squeezing deformation decrease. In alternate fracturing, starting from a well located in the middle can effectively reduce the influence of stratal movement on fracturing, and the fracturing scenario with cross-perforation can minimize the influence of stratal movement. The stratal movement between multiple wells is positively correlated to microseismic events, which behaviors can be effectively weakened by reducing the strata movement.

The fracture network, thermal-hydro-mechanical coupling, fracturing-induced stratal movement and microseismic events were analyzed. This study analyzed the intersection and propagation behavior of fractures in multi-well hydrofracturing, which can be used to evaluate and study the mechanism of hydrofracturing fracture network propagation in multiple horizontal wells and conduct fracture optimization research to form an optimized hydrofracturing scheme by reasonably arranging the spacing between wells and initiation sequences of perforation clusters.

The purpose of this paper is to explore how family-supportive supervisor behaviour (FSSB) and organisational work–family policies (WFP) influence turnover intention (TI), satisfaction with work–family balance (SWFB) and prosocial motivation (PSM) in employees in organisations in the private sector in Colombia and Chile. It also explores whether a family -friendly organisational culture (FFOC) moderates this relationship.

A questionnaire (the International Family-Responsible Employed Index) was used to survey 486 employees (Chile: 255, Colombia: 231). The questionnaire consisted of three main sections: independent variables (WFP, FSSB, (FFOC and individual characteristics); dependent variables (organisational outcomes of TI, loyalty and commitment, and individual outcomes of health, WFE, SWFB, PSM and intrinsic); and demographic indicators. Structural equation modelling was used to test the possibility of comparing both countries and the model proposed.

Results show a negative relationship between FSSB and TI, and a positive relationship between FSSB and SWFB and PSM. There are no significant differences among countries, except when looking at PSM. FFOC moderates the relationships between FSSB and TI, between policies and FSSB and SWFB and between FSSB and PSM. It also has a direct effect on PSM.

This paper is one of the first to offer comparative data from organisations and managers in Latin American countries at the work–family interface. It also contributes to the literature, offering results partly consistent with studies in Anglo–Saxon countries.

Este estudio explora cómo los comportamientos solidarios de los supervisores y las políticas de apoyo para el balance entre trabajo-familia influyen en la intención de dejar la empresa, la satisfacción con el balance trabajo-familia y la motivación pro-social de los empleados en organizaciones en el sector privado en Colombia y Chile. Además, se centra en cómo una cultura amigable para las familias modera la relación.

El cuestionario IFREI (International Family-Responsible Employed Index) fue utilizado para recabar información de 486 empleados (Chile: 255, Colombia: 231). El cuestionario consta de tres partes principales: variables independientes (Políticas Trabajo-Familia (WFP), Comportamientos solidarios de supervisores (FSSB), Cultura organizacional amigable para la familia (FFOC), y características individuales); variables dependientes (resultados organizacionales de intenciónde dejar la empresa, lealtad y compromiso; y resultados individuales de salud, enriquecimiento trabajo-familia, satisfacción con el balance trabajo-familia (SWFB) y motivación: pro-social (PSM) e intrínseca; e indicadores demográficos. Se usa ecuaciones estructuradas para probar la posibilidad de comparar ambos países y el modelo propuesto.

Los resultados muestran una relación negativa entre comportamientos solidarios e intención de dejar la empresa y una relación positiva entre comportamientos solidarios de supervisores y satisfacción con el balance trabajo-familia y motivación pro-social. No hay diferencias significativas entre los países, excepto en lo que se refiere a motivación pro-social. La cultura organizacional amigable para la familia modera la relación entre comportamientos solidarios de los supervisores y la intención de dejar la empresa, entre políticas y FSSB y SWFB, y entre FSSB y PSM. La cultura organizacional amigable a la familia tiene un efecto directo en la motivación pro-social.

Este trabajo es uno de los primeros en ofrecer información comparativa entre organizaciones y directivos de países Latinoamericanos alrededor de la esfera trabajo-familia. También contribuye a la literatura ofreciendo resultados parcialmente consistentes con estudios de países anglosajones.