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61.
The Cd−Zn system has been thermodynamically reassessed with the CALPHAD method by combining more recent experimental data,
in particular the activities of zinc in the liquid phase. A good agreement is obtained between the calculated and experimental
thermodynamic parameters as well asphase boundaries. 相似文献
62.
63.
Xiao Teng-Fei Li Xiao-Dong Ho John K. L. 《International Journal of Control, Automation and Systems》2015,13(1):222-230
In this article, a novel fuzzy systems based on adaptive Iterative Learning Control (ILC) strategy is presented to deal with a class of non-parametric nonlinear discrete-time systems which perform iteration-varying reference trajectory tracking. Using the technique of fuzzy systems to compensate for the non-parametric uncertainty of the discrete-time system dynamics, the proposed adaptive ILC scheme can well track the iteration-varying reference trajectory beyond the initial time points. The convergence of the fuzzy systems based adaptive ILC algorithm is guaranteed by theoretical analysis, and a numerical example is given to illustrate the effectiveness of the adaptive ILC scheme.
相似文献64.
65.
The aim of our study was to further develop an understanding of social capital in organizational-knowledge-sharing. We first developed a measurement tool and then a theoretical framework in which three social capital factors (social network, social trust, and shared goals) were combined with the theory of reasoned action; their relationships were then examined using confirmatory factoring analysis. We then surveyed of 190 managers from Hong Kong firms, we confirm that a social network and shared goals significantly contributed to a person's volition to share knowledge, and directly contributed to the perceived social pressure of the organization. The social trust has however showed no direct effect on the attitude and subjective norm of sharing knowledge. 相似文献
66.
Translucent scattering phantoms hidden inside a 5.5-cm-thick Intralipid solution were imaged as a function of phantom scattering coefficients by the use of a picosecond time- and space-gated Kerr-Fourier imaging system. A 2-mm-thick translucent phantom with a 0.1% concentration (scattering coefficient) difference from the 55-mm-thick surrounding scattering host can be distinguished at a signal level of ~10(-10) of the incidence illumination intensity. 相似文献
67.
Jung Joon Lee 《Photographies》2017,10(3):245-264
This essay examines Kim Yongt’ae’s photocollage DMZ, which consists of photo-portraits he acquired from commercial photo studios in US military camptowns in South Korea. The co-founding member of the South Korean artist group Hy?nsilgwa par?n (Reality and Utterance), Kim visited camptowns in 1984. There, he found hundreds of studio photo-portraits depicting Korean women and American GIs serving United States Forces Korea (USFK). While discussions on “found” photographs often center on the discourses of archive, appropriation, or vernacularity appended by the cultural specificity of their origins, this essay proposes a new framework through which Kim’s work is explored: transnational militarism and “disidentification” — a concept put forth by José Esteban Muñoz on minoritarian performativity. Through this framework, DMZ challenges the binary reading of camptown subjects as victim and victimizer and proposes the performative formation of a new subjectivity. 相似文献
68.
Sang-Min Lee Jeong-Won Yoon Seung-Boo Jung 《Journal of Materials Science: Materials in Electronics》2016,27(2):1105-1112
The electromigration behavior of low-melting temperature Sn-58Bi (in wt%) solder joints was investigated with a high current density between 3 and 4.5 × 103 A/cm2 between 80 and 110 °C. In order to analyze the impact of various substrate metallizations on the electromigration performance of the Sn-58Bi joint, we used representative substrate metallizations including electroless nickel immersion gold (ENIG), electroless nickel electroless palladium immersion gold (ENEPIG), and organic solderability preservatives (OSP). As the applied current density increased, the time to failure (TTF) for electromigration decreased regardless of the temperature or substrate metallizations. In addition, the TTF slightly decreased with increasing temperature. The substrate metallization significantly affected the TTF for the electromigration behavior of the Sn-58Bi solder joints. The substrate metallizations for electromigration performance of the Sn-58Bi solder are ranked in the following order: OSP-Cu, ENEPIG, and ENIG. Due to the polarity effect, current stressing enhanced the fast growth of intermetallic compounds (IMCs) at the anode interface. Cracks occurred at the Ni3Sn4 + Ni3P IMC/Cu interfaces on the cathode sides in the Sn-58Bi/ENIG joint and the Sn-58Bi/ENEPIG joint; this was caused by the complete consumption of the Ni(P) layer. Alternatively, failure occurred via deformation of the bulk solder in the Sn-58Bi/OSP-Cu joint. The experimental results confirmed that the electromigration reliability of the Sn-58Bi/OSP-Cu joint was superior to those of the Sn-58Bi/ENIG or Sn-58Bi/ENEPIG joints. 相似文献
69.
70.
To make health care more responsive to patient needs, insight into patient priorities is needed. A systematic literature review, using electronic and manual searches, was made of studies on patient priorities with regard to primary health care. Data-extraction was performed by two researchers, followed by systematic analyses of study features. 57 studies were included. The aspects of care and methods used showed a wide variation. Aspects most often included were "informativeness", "humaneness" and "competence/accuracy". Based on an analysis of 19 studies, the following aspects were seen by patients as most important in more than 50% of the studies that included them: "humaneness", "competence/accuracy", "patients' involvement in decisions", "time for care", "other aspects of availability/accessibility", "informativeness", "exploring patients' needs", "other aspects of relation and communication" and "availability of special services". 相似文献