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The purpose of this study is to examine the effects of inclination angle on the thermal energy storage capability of a phase change material (PCM) within a disc-shaped container. Different container materials are also tested such as plexiglass and aluminium. This study aims to assess the energy storage capacity, melting behaviour and temperature distributions of PCM with a specific melting range (22°C–26°C) for various governing parameters such as inclination angles, aspect ratios (AR) and temperature differences (ΔT) and compare the melting behaviour and energy storage performance of PCM in aluminium containers to those in plexiglass containers.

A finite volume approach was adopted to evaluate the thermal energy storage capability of PCMs. Five inclination angles ranging from 0° to 180° were considered and the energy storage capacity. Also, the melting behaviour of the PCM and temperature distributions of the container with different materials were tested. Two different AR and ΔT values were chosen as parameters to analyse for their effects on the melting performance of the PCM. Conjugate heat transfer problem is solved to see the effects of conduction mode of heat transfer.

The results of the study indicate that as AR decreases, the effect of the inclination angles on the energy storage capacity of the PCM decreases. For lower ΔT, the difference between the maximum and minimum stored energies was 20.88% for AR = 0.20, whereas it was 6.85% for AR = 0.15. Furthermore, under the same conditions, the PCM stored 8.02% more energy in plexiglass containers than in aluminium containers.

This study contributes to the understanding of the influence of inclination angle, container material, AR and ΔT on the thermal energy storage capabilities of PCM in a novel designed container. The findings highlight the importance of AR in mitigating the effect of the inclination angle on energy storage capacity. Additionally, comparing aluminium and plexiglass containers provides insights into the effect of container material on the melting behaviour and energy storage properties of PCM.

Inclination angle has been reported to have an enhancing effect on the thermal-hydraulic characteristics and entropy of some thermal systems. Therefore, this paper aims to numerically investigate the effects of inclination angle, volume concentration and Reynolds number on the thermal and hydraulic characteristics and entropy generation rates of water-based Al₂O₃ nanofluids through a smooth circular aluminum pipe in a turbulent flow.

A constant heat flux of 2,000 Watts is applied to the circular surface of the tube. Reynolds number is varied between 4,000 and 20,000 for different volume concentrations of alumina nanoparticles of 0.5%, 1.0% and 2.0% for tube inclination angles of ±90o, ±60o, ±45o, ±30o and 0o, respectively. The simulation is performed in an ANSYS Fluent environment using the realizable kinetic energy–epsilon turbulent model.

Results show that +45o tube orientation possesses the largest thermal deviations of 0.006% for 0.5% and 1.0% vol. concentrations for Reynolds numbers 4,000 and 12,000. −45o gives a maximum pressure deviation of −0.06% for the same condition. The heat transfer coefficient and pressure drop give maximum deviations of −0.35% and −0.39%, respectively, for 2.0% vol. concentration for Reynolds number of 20,000 and angle ±90o. A 95%–99.8% and 95%–98% increase in the heat transfer and total entropy generation rates, respectively, is observed for 2.0% volume concentration as tube orientation changes from the horizontal position upward or downward.

Research investigating the effect of inclination angle on thermal-hydraulic performance and entropy generation rates in-tube turbulent flow of nanofluid is very scarce in the literature.

Integrating identity theory and role theory, this study examines the re-expatriation inclinations of highly-skilled professional female self-initiated repatriates (SIRs) in an Asian rapidly emerging market (REM) and the reasons underlying these inclinations.

The authors conducted a survey on a sample of highly-skilled professional female SIRs in Vietnam (N = 248). Structural equation modelling was used to evaluate the model.

The study found that female SIRs' career identity, family identity and social identity have a significant influence on their inclinations to re-expatriate. Attitude towards re-expatriation fully mediates the influence of family identity and career identity on re-expatriation inclinations.

This research was limited to female SIRs in one REM, namely Vietnam, and may lack generalisability in countries and contexts.

By delineating the identity-related factors that contribute to skilled female SIRs' inclinations to re-expatriate and recognising gender as a complex, multifaceted social construct, the authors broaden the way expatriation is conceptualised and isolate factors that can inform practices for recruitment and retention of this important sub-set of international talent.

Individual factors associated with managers' organisational alcohol policy knowledge and inclination to initiate early alcohol interventions have been understudied. This study aims to examine differences in managers' policy knowledge and inclination across a range of socio-demographic, work-related and health characteristics, and it aims to examine the association between policy knowledge and inclination to intervene, net of these characteristics.

Questionnaire data were collected from 430 managers. Organisational alcohol policy knowledge and inclination to intervene were measured using a 5-point Likert scale ranging from 1 (very low) to 5 (very high). Socio-demographic, work-related and health characteristics included gender, age, education, managerial responsibility, years in current position, self-rated health and alcohol consumption. Associations were examined using multilevel ordinal regression analysis.

Managers with a greater number of employees demonstrated the highest level of organisational alcohol policy knowledge and were more inclined to initiate early alcohol interventions. Alcohol policy knowledge was associated with inclination to intervene, net of individual characteristics.

Considering how managers' characteristics might influence efforts to decrease hazardous alcohol consumption is potentially important when designing future workplace alcohol prevention programmes.

Several individual factors related to managers' organisational alcohol policy knowledge and inclination to initiate early alcohol interventions were identified, particularly managerial responsibility. However, the association between policy knowledge and inclination to intervene remained strong after accounting for these individual factors. Future studies should explore alternative explanations at the individual and organisational levels.

The purpose of this paper is to show how behavioral descriptions in psychology and group dynamics can be related to four goal-setting processes and to four mode of existence.

Some person A can approach a person B with an inclination to realize one of four goal-setting processes: (1) A sets goals for B; (2) A sets no own goals; (3) A pursues own goals alone; (4) A and B develop mutual goals. Depending on their choice of inclinations an interaction of A and B can lead to four modes of coexistence: (1) Conflict – A and B fight; (2) Hierarchy – A submits to B; (3) Independence in niches – A and B do not interact; (4) Cooperation – A and B work together. The paper investigates how these theoretical options – four inclinations for different goal-set processes and four modes of coexistence – show in behavioral descriptions in psychology and group dynamics.

Psychic states studied in psychology (e.g. by Freud, Berne, Horney) can be related to one of the four inclinations. Interaction patterns studied in group dynamics (e.g. by Steiner, Schindler, Bion) describe aspects of the four modes of coexistence.

Behavioral descriptions of various schools of psychology and group dynamics can be classified according to theoretically derivable basic options of goal-orientated behavior.

The paper shows the application of a theoretical framework covering all options of goal-orientated behavior available in the behavioral sciences.

The purpose of this paper is to study the effect of J₃ perturbation of the Earth’s oblateness on satellite orbit compared with J₂ perturbation.

Based on the parametric variation method in the time domain, considering more accurate Earth potential function by considering J₃-perturbation effect, the perturbation equations about satellite’s six orbital elements (including semi-major axis, orbit inclination, right ascension of the ascending node, true anomaly, eccentricity and argument of perigee) has been deduced theoretically. The disturbance effects of J₂ and J₃ perturbations on the satellite orbit with different orbit inclinations have been studied numerically.

With the inclination increasing, the maximum of the semi-major axis increases weakly. The difference of inclination disturbed by the J₂ and J₃ perturbation is relative to orbit inclinations. J₃ perturbation has weak effect on the right ascension and argument of perigee. The critical angle of the right ascension and argument of perigee which decides the precession direction is 90° and 63.43°, respectively. The disturbance effects of J₂ and J₃ perturbations on the argument of perigee, right ascension and eccentricity are weakened when the eccentricity increases, simultaneously, the difference of J₂ and J₃ perturbations on argument of perigee, right ascension and argument of perigee decreases with eccentricity increasing, respectively.

In the future, satellites need to orbit the Earth much more precisely for a long period. The J₃ perturbation effect and the weight compared to J₂ perturbation in LEO can provide a theoretical reference for researchers who want to improve the control accuracy of satellite. On the other hand, the theoretical analysis and simulation results can help people to design the satellite orbit to avoid or diminish the disturbance effect of the Earth’s oblateness.

The J₃ perturbation equations of satellite orbit elements are deduced theoretically by using parametric variation method in this paper. Additionally, the comparison studies of J₂ perturbation and J₃ perturbation of the Earth’s oblateness on the satellite orbit with different initial conditions are presented.

The objective of present research is to characterize the unsteady thermal behavior of a square enclosure filled with water-Al₂O₃ nanofluids in the presence of oriented magnetic fields. The purpose this paper is to study the effect of pertinent parameters on the transient natural convection in the enclosure.

In this research, an in-house implicit finite volume code based on the SIMPLE algorithm is utilized for numerical calculations. To ensure the accuracy of results, comparisons are also made with previous works in literature. In this study, a constant strength magnetic field is concerned and for Rayleigh numbers of Ra=103, 104 and 105 the effect of magnetic field orientation with respect to the case of zero inclination on the thermal performance of cavity is investigated at Hartmann number range of Ha=15-90. In the present work, the nano-particle volume fractions range from φ=0-0.06.

Results show that when Rayleigh number is Ra=103, the inclination angle, solid particles and Hartmann number has no effect on the transient behavior. It is shown that during the time advancement to steady condition, the heat transfer rate relative to zero inclination angle, may reach to a maximum value. This relative maximum heat transfer increases as the inclination angle increases and decreases as the solid volume fraction increases. The effect of increase in Hartmann number is to decrease this maximum value at Rayleigh number of Ra=104 and at Rayleigh number of Ra=105, depending on the Hartmann number, this value may increase or decrease. It is also found that an increase in Hartmann number leads to delay the appearance of the relative maximum value of heat transfer. Results show that this maximum value is of more significance at zero solid volume fraction when inclination angle is 90 degrees and Hartmann number is Ha=60.

Limited works could be found in the literature regarding the idea of using nanofluids as the working fluid in an enclosure in the presence of magnetic field. In these works, the steady state thermal behavior of enclosures subjected to fixed magnetic fields is concerned. In the present work, the unsteady thermal behavior is concerned and the effect of magnetic field orientation angles on transient heat transfer performance of the enclosure at different Rayleigh and Hartmann numbers and solid volume fractions is explored.

The purpose of this paper is to show how individual acts of goal-setting of two persons or systems A and B determine, which modes of coexistence become possible in an interaction of the two.

Some person or system A can approach another person or system B with an inclination to realize one of four goal-setting processes: first, A sets goals for B; second, A sets no own goals; third, A pursues own goals alone; and fourth, A and B develop mutual goals. And an interaction of A and B can lead to just four modes of coexistence: first, conflict – A and B fight; second, hierarchy – A submits to B; third, independence in niches – A and B do not interact; and fourth, cooperation – A and B work together.

Placing the inclinations of A and B to realize one of the four goal-setting processes in a 4×4 matrix leads to the interaction matrix. It shows that individual goal-setting processes predetermine and limit the available modes of coexistence, i.e. cause certain patterns of interactions.

The interaction matrix can be applied to all interactions between persons, groups and social units generally.

The paper introduces a theoretical framework covering all options of goal-orientated behavior. It explains the interrelation between individual goal-setting of persons and systems and the resulting behavioral options in interactions. It is applicable to all behavioral sciences.

Most past studies on studentsʼ entrepreneurial intention tend to focus on the phenomenon in developed countries.There is limited research on entrepreneurial intention of university students from developing nations. This article intends to close this gap by providing some insights into students℉ entrepreneurial inclination in a developing country, Malaysia. A total of 234 students from three faculties at both graduate and undergraduate levels were surveyed to examine their entrepreneurial inclination and also to examine the relationship between their demographic and social characteristics with entrepreneurial inclination.The study found strong entrepreneurial inclination among the students. Significant difference was found between students studying part time and full time and their entrepreneurial inclination. Significant difference was also found between the type of program enrolled in and students℉ entrepreneurial inclination. Further analysis and other findings were reported and recommendation for future research are been put forth in this article.

The purpose of this paper is to study numerically thermosolutal natural convection within an inclined rectangular cavity in the presence of Soret effect and heat generation. The enclosure is heated and salted from its long sides with constant but different temperatures and concentrations. The study focuses on the effects of three main parameters which are, the Soret parameter (Sr = 0 and –0.5), the internal to external Rayleigh numbers ratio 0 ≤ R ≤ 80 and the cavity inclination γ, varied from 0° (vertical position) to 60°. The combined effects of these parameters on fluid flow and heat and mass transfer characteristics are examined for the external Rayleigh number Ra_E = 10⁵, the Prandtl number Pr = 0.71, the buoyancy ratio N = 1, the Lewis number Le = 2 and the aspect ratio of the cavity A = 2.

A hybrid lattice Boltzmann-finite difference method (LBM-FD) was used to tackle the problem under consideration. The LBM with the simple relaxation time was used for the fluid flow in the presence of the gravity force, while the temperature and concentration equations were solved separately using an explicit finite-difference technique at the Boltzmann scale.

The monocellular nature of the flow, obtained for R = 0 is not destroyed by varying the cavity inclination and the Soret parameter but rather by the increase of the parameter R. The Soret parameter and the cavity inclination become perceptible at high values of R. The inclination γ = 60° leads to high mean temperatures compared to the other inclinations. The effect of R on mean concentration is amplified in the presence of Soret effect but limited in the absence of the latter. The negative Soret parameter combined with high internal heat generation and a relatively high inclination is important when the objective is to maintain the fluid at a high concentration of species. The presence of bicellular flow combined with the important elevation undergone by the fluid temperature, makes both the cold and hot walls playing a cooling role with the most important exchanges taking place at the upper part of these walls. The analysis of the mean mass transfer shows that the increase of the inclination may lead to an increase or a decrease of the mass transfer depending on the range of R, in the case of Sr = 0. However, for Sr = −0.5, it is observed that the increase of γ is generally accompanied by a reduction of the mass transfer.

To the best of the authors’ knowledge, the hybrid LBM-FD was not used before to study such a problem. Combined effect of R and inclination may be useful in charging the fluid with species when the objective is to maintain high concentrations in the medium.