Higher data rate hard disk drives(HDD) and improved read channel electronics are demanding preamplifier performance be extended well beyond 1 Gb/s. Historically, preamplifier power requirements were of low priority; however, with increased demand for battery powered devices such as laptops, MP3 players, personal video recorders, andmanyother wireless hand-held devices, power consumption has become an important design parameter.Furthermore, in order to continue to increase drive capacities, new read-write head technologies(vertical recording and TGMR heads) are demanding innovative preamplifier circuitsolutions.Today's production preamplifiers possess a wide band response of 2.5 MHz-600 MHz; however next generation preamplifiers willrequire response greater than 250 KHz-1 GHz.Low corner frequencies below 250 KHz present read recovery (sleep-to-read, write-to-read, etc) challenges which can limit drive capacity. This project targets a > 2 Gb/s TGMR (tunneling giantmagneto-resistive) read path for verticalrecording HDDs. A high performance BiCMOS process (IBM's 0.5?m 5HP process)is essential due to the large transconductances, low noise and highspeed requirements of the read path's first stage. System frequency limitations at the input are a result of the large TGMR read sensor and preamplifier input capacitance. Due to read head and preamplifier manufacturingvariations, resistive feedbackaroundthe firststage is usedto seta controlled input impedance targeted to match the interconnect transmission line. Head resistance variations lead to gain variations; however, the TGMR element becomes more sensitive with larger resistance. This, to a first order approximation, acts like an automatic gain control and reduces variations in gain due to the head.

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Organizations nowadays want employees who are flexible, adaptable, autonomous, creative, willing to learn, self-motivated, and able to fit productively into teams to satisfy instable and varied consumer demands. Consequently, job performance no more relies on repetitive and routine tasks which traditionally could be completed and improved by working-hard only. Nevertheless, the economy in the world is becoming dynamic, rapid and unpredictable for sure. Transparently workers will need to unceasingly increase their skill base to experience workplace success in the future. Therefore, management scholars suggest organizations who want to survive or outperform of the time may need to consider traits in addition of conscientiousness when making hiring decisions. The Big Five undoubtedly provides the general and basic consideration of personality. As the environment nowadays changes, not only the Big Five but also more advanced and specific personality constructs for advantageous solutions hitting the mark are needed. Playfulness, defined as a multidimensional personality with curiosity, absorption, sense of humor, manifest joy and childlikeness factors, may be one promising personality which replies the call from the academic and plays as the alternative selection assessment tool for selection to the practical simultaneously. Playfulness has been emphasized in child development, education, and clinical counseling fields for a long time. This personality fosters optimal human function and accompanies intrinsic motivation according to developmental psychology and positive psychology perspectives. Notwithstanding its importance, playfulness in adults does not catch enough attention of the academic. This study first empirically tests relationship between playfulness and job performance (in-role performance, creative performance) and clarifies the discrepancy of style effects on different dimensions of performance which may better explain the phenomena in the workplace. Second, this study moves a step forward to propose a personality construct from developmental psychology triangle especially favorable to selection consideration. Third, through the lens of working behavior style, the results of this study also better explain the mechanism link playfulness and performance that throw light on training direction for people in organizations already. By defining working-smart/hard as behavioral style instead of ability and motivation, this study opens a new avenue for research to discuss the issue thoroughly. Future research suggestions and practical applications are also provided.

In recent years, series of high-entropy alloy have been well developed with high hardness and high temperature stability. These properties could apply in hard surface welding technology. The previous research showed that Al0.5CoCrCuFeNi based alloy contained excellent abrasive and adhesive wear resistant properties. According to the results of first year project, the post heat treatment is required for Type A (Al0.3CrFe1.5MnNi0.5 ) and B (Al0.5CrFe1.5MnNi0.5) alloys. It is not suitable for the industrial field service in certain repairing application. This research project will modify the Al0.5CrFe1.5MnNi0.5 base high-entropy alloy in the alloy content of Cr and Ni. These new alloy called Type D high entropy alloys include BCC and FCC two phases. We expect BCC part will provide the wear hardness and FCC part could improve the ductility during the wearing stage. The FCC phase may improve the manufacture of welding rods, also. The research contents include, (1) Type D high entropy alloys weld rod evaluation, (2) wear test, (3) microstructure analysis using electron micro-probe

Higher data rate hard disk drives(HDD) and improved read channel electronics are demanding preamplifier performance be extended well beyond 1 Gb/s. Historically, preamplifier power requirements were of low priority; however, with increased demand for battery powered devices such as laptops, MP3 players, personal video recorders, andmanyother wireless hand-held devices, power consumption has become an important design parameter.Furthermore, in order to continue to increase drive capacities, new read-write head technologies(vertical recording and TGMR heads) are demanding innovative preamplifier circuitsolutions.Today's production preamplifiers possess a wide band response of 2.5 MHz-600 MHz; however next generation preamplifiers willrequire response greater than 250 KHz-1 GHz.Low corner frequencies below 250 KHz present read recovery (sleep-to-read, write-to-read, etc) challenges which can limit drive capacity. This project targets a > 2 Gb/s TGMR (tunneling giantmagneto-resistive) read path for verticalrecording HDDs. A high performance BiCMOS process (IBM's 0.5?m 5HP process)is essential due to the large transconductances, low noise and highspeed requirements of the read path's first stage. System frequency limitations at the input are a result of the large TGMR read sensor and preamplifier input capacitance. Due to read head and preamplifier manufacturingvariations, resistive feedbackaroundthe firststage is usedto seta controlled input impedance targeted to match the interconnect transmission line. Head resistance variations lead to gain variations; however, the TGMR element becomes more sensitive with larger resistance. This, to a first order approximation, acts like an automatic gain control and reduces variations in gain due to the head.

<p><p>I denna uppsats behandlas vetenskapliga kategoriseringar av nyheter, närmare bestämt de två kategorierna hard news och soft news. Utifrån tre akademiska texter presenteras definieringar, värderingar och betänkanden som författarna till dessa texter gjort. Utgångspunkten för problematiseringen av nyhetskategoriseringarna har varit att belysa saken från ett socialkonstruktionistiskt perspektiv. Ett försök till detta har gjorts med dels en relativt allmän genomgång av socialkonstruktionismens grundprinciper, formulerade av Marianne Winther Jørgensen & Louise Philips, och dels med en fördjupning i den socialkonstruktionistiska grenen diskursteori såsom den formuleras av Michel Foucault. Utifrån detta görs en analys av de tre texterna utifrån hur de används för att etablera tolkningsföreträden och rättfärdiga de olika definieringarna, värderingarna och betänkandena som författarna lägger fram. Avslutningsvis förs en diskussion om det forskningsmässiga läget beträffande hard news och soft news.</p></p> / -

With highly demanding requirement in current emerging cloud storage and personal computers, hard disk drive recording with high stability and high volume has attached much attention in industry and academy. Recording media and recording head feasible for future high-density recording are both crucial to utilize magnetic recording with 1T bit/in2 recording density. Recoding media with FePt for high density and high stability was investigated in this thesis using FePt polymers with imprinting methods and FePt thin films with ion-beam bombardment technologies. The FePt polymers can be patterned using imprint at micro-and nano-scales. The micro-and nano-patterns could be retained on substrates after sintering at high temperatures. The high magnetic coercivity was proved with line and dot patterns at different scales. Recording heads with Al2O3based magnetic tunneling junction sensors were also studied in thesis. The magnetic tunneling junction sensors were proved to work stable at different temperatures varying from -30oC to 100oC. The long time running test up to 100 hours also proved the stability of the magnetic tunneling junction sensors working in extreme temperatures. Withstate-of-art patterning and depositing technologies, new ideas about using FePt polymer to work as magnetic recording media and using ion beam bombardments to tune the FePt magnetic properties were verified. The feasibility of using Al2O3 based magnetic tunneling junction sensors as recording head was also discussed. / published_or_final_version / Electrical and Electronic Engineering / Doctoral / Doctor of Philosophy

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Ab initio plane wave based density functional calculations within the generalised gradient approximation (GGA) have been carried out on a wide range of phases and stoichiometries for the platinum-titanium (Pt-Ti) and iridium-titanium (Ir-Ti) alloy systems, using the Vienna Ab Initio Simulation Package (VASP) with projector augmented wave (PAW) potentials. For all of the phases in this work, the equilibrium structures were found by performing a full relaxation of the atoms. There were 20 di erent phases considered for varying atomic percentage compositions for each alloy system. Energy-volume calculations and heats of formations were used to determined the equilibrium structures at each atomice percentage composition and to determine if there were high temperature phases at that composition. The elastic constants and elastic moduli are calculated and the electronic structure and density of states (DOS) were considered to understand the hardness and stability properties of the alloys. For the Pt-Ti system, the low and high temperature phases at di erent compositions agreed with previously published results in the literature. Intermediate phases at 50% were also determined, in agreement with previous results. Alloying Pt with Ti resulted in a decrease in the bulk modulus, i.e. not adding strength to the metal. However, the shear modulus increased for most of the alloys compared to bulk Pt and it was found that in general, alloying may increase the resistance to shear. PtTi alloys were found to be ductile in nature, as with both constituent metals in their bulk form. In the Ir-Ti system, bulk Ir was found to have the highest bulk, shear and Young's modulus with each of these values decreasing with increasing percentage Ti in the alloy. IrTi alloys with 66.7% Ir composition or higher were found to be brittle in nature, similar in behaviour to bulk Ir; alloys with a higher percentage concentration of Ti were found to be ductile. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.

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