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Tin-Silver-Copper is widely accepted as the best alternative to replace Tin-Lead solders in microelectronics packaging due to their acceptable properties. However, to overcome some of the shortcomings related to its microstructure and in turn, its mechanical properties at high temperature, the addition of different elements into Tin-Silver-Copper is important for investigations. The purpose of this paper is to analyse the effect of lanthanum doping on the microstructure, microhardness and tensile properties of Tin-Silver-Copper as a function of thermal aging time for 60, 120 and 180 h at a high temperature of 150°C and at high strain rates of 25, 35 and 45/s.

The microstructure of un-doped and Lanthanum-doped Tin-Silver-Copper after different thermal aging time is examined using scanning electron microscopy followed by digital image analyses using ImageJ. Brinell hardness is used to find out the microhardness properties. The tensile tests are performed using the universal testing machine. All the investigations are done after the above selected thermal aging time at high temperature. The tensile tests of the thermally aged specimens are further investigated at high strain rates of 25, 35 and 45/s.

According to the microstructural examination, Tin-Silver-Copper with 0.4 Wt.% Lanthanum is found to be more sensitive at high temperature as the aging time increases which resulted in coarse microstructure due to the non-uniform distribution of intermetallic compounds. Similarly, lower values of microhardness, yield strength and ultimate tensile strength come in favours of 0.4 Wt.% Lanthanum added Tin-Silver-Copper. Furthermore, when the thermally aged tensile specimen is tested at high strains, two trends in tensile curves of both the solder alloys are noted. The trends showed that yield strength and ultimate tensile strength increase as the strain rate increase and decrease when there is an increase in thermal aging.

The addition of higher supplement (0.4 Wt.%) of Lanthanum into Tin-Silver-Copper showed a lower hardness value, yield strength, ultimate tensile strength, ductility, toughness and fatigue in comparison to un-doped Tin-Silver-Copper at high temperature and at high strain rates. Finally, simplified material property models with minimum error are developed which will help when the actual test data are not available.

This paper argues that teachers’ promotion should also have an impact on turnover intention. The purpose of this paper is to determine the relationship between promotion and turnover intention of advance learning institutions of the Khyber Pakhtoon Khwa Province of Pakistan and the moderating effect of the analytical cognitive style.

A quantitative approach is used predominantly. A questionnaire survey research design is used to collect the data from the entire province and 502 completed questionnaires were collected from the respondents. The questionnaire included the Job Descriptive Index consisting of seven items on job satisfaction, the turnover intention questionnaire consisting of three items and a five-point Likert scale used to determine cognitive style index (CSI); the CSI was used. The fourth section included an open-ended questionnaire and the fifth section included demographic variables. Hierarchical multiple regressions were used to check how much variance promotion occurs upon turnover intention and it also determined how much variance analysis cognitive style occurs upon promotion and turnover intention of advance learning institutions of the KPK province of Pakistan. The correlation results from a bivariate Pearson correlation showed significant results, which were later strengthened by the regression results.

The findings suggested that a negative relationship was found between promotion and turnover intention, whereas a weak correlation was found between promotion and analytical. Moderating results show that analytical cognitive style does act as a moderator between the promotion and turnover intention.

This research was only carried out on advance learning institutions; thus, the findings can only be generalized to higher education institutions in the Khyber Pakhtoon Khwa state.

This extended model of job satisfaction will be useful to lead to changes in job satisfaction and turnover intention of academicians of the Khyber Pakhtoon Khwa province of Pakistan. The findings of this study could be used to guide the management of advance learning institutions and professional academicians to build targeted learning activities around key components of the academician’s promotion, determine where individuals are in their journey, set personalized goals and provide feedback to the management in the process of the development of policies for academicians of advance learning institutions.

The findings of this study will help the higher education commission of Pakistan to make policies that will enable higher education institutions to formulate flexible promotion policies for teachers in order to retain them.

The findings of this study are a valuable extension of the relevant research as this is the first empirical study to examine the effects of cognitive style on promotion policies and turnover intention in advance learning institutions of Pakistan. In the context of an efficient and effective educational policy, a greater understanding of an academician’s promotion could facilitate the development of a more effective policy practice that would increase not only the job satisfaction of the academicians but decrease the turnover intention of the academicians.