Infinite systems of non-colliding generalized meanders and Riemann-Liouville differintegrals

Yor's generalized meander is a temporally inhomogeneous modification of the $2(\nu+1)$-dimensional Bessel process with $\nu > -1$, in which the inhomogeneity is indexed by $\kappa \in [0, 2(\nu+1))$. We introduce the non-colliding particle systems of the generalized meanders and prove that they are the Pfaffian processes, in the sense that any multitime correlation function is given by a Pfaffian. In the infinite particle limit, we show that the elements of matrix kernels of the obtained infinite Pfaffian processes are generally expressed by the Riemann-Liouville differintegrals of functions comprising the Bessel functions $J_{\nu}$ used in the fractional calculus, where orders of differintegration are determined by $\nu-\kappa$. As special cases of the two parameters $(\nu, \kappa)$, the present infinite systems include the quaternion determinantal processes studied by Forrester, Nagao and Honner and by Nagao, which exhibit the temporal transitions between the universality classes of random matrix theory.Comment: LaTeX, 35 pages, v3: The argument given in Section 3.2 was simplified. Minor corrections were mad

Investigating the electronic properties of multi-junction ZnS/CdS/CdTe graded bandgap solar cells

The fabrication of multi-junction graded bandgap solar cells have been successfully implemented by electroplating three binary compound semiconductors from II-VI family. The three semiconductor materials grown by electroplating techniques are ZnS, CdS and CdTe thin films. The electrical conductivity type and energy bandgap of each of the three semiconductors were determined using photoelectrochemical (PEC) cell measurement and UV-Vis spectrophotometry techniques respectively. The PEC cell results show that all the three semiconductor materials have n-type electrical conductivity. These two material characterisation techniques were considered in this paper in order to establish the relevant energy band diagram for device results, analysis and interpretation. Solar cells with the device structure glass/FTO/n-ZnS/n-CdS/n-CdTe/Au were then fabricated and characterised using current-voltage (I-V) and capacitance-voltage (C-V) techniques. From the I-V characteristics measurement, the fabricated device structures yielded an open circuit voltage (Voc) of 670 mV, short circuit current density (Jsc) of 41.5 mAcm-2 and fill-factor (FF) of 0.46 resulting in ∼12.8% efficiency when measured at room temperature under AM1.5 illumination conditions. The device structure showed an excellent rectification factor (RF) of 104.3 and ideality factor (n) of 1.88. The results obtained from the C-V measurement also showed that the device structures have a moderate doping level of 5.2×1015 cm-3

Natural convection induced by diurnal heating and cooling in a reservoir with slowly varying topography

This study is concerned with natural convection in a reservoir with slowly varying topography in response to diurnal heating and cooling due to heat transfer through the water surface. In the daytime phase, heat is transferred into the water body through absorption of solar radiation; and in the night-time phase, heat is transferred out of the water body through heat loss from the water surface. An unsteady model is formed and solved numerically in order to investigate the transient flow response in the reservoir. Two different scenarios with shallow and deep waters respectively, based on the comparison between the maximum water depth and the penetration depth of the solar radiation, are considered. The numerical results reveal that there is a distinct time lag in the response of the overall flow to the switches of the thermal forcing, and the lag time depends on the Grashof number. It is also found that thermal instabilities play an important role in breaking the residual circulation and reversing the flow in deep waters

Supporting innovation through HR policy: evidence from the UK

This paper focuses on the relationship between the importance of innovation for organizations and their human resources policy. Drawing on survey findings, we examine the coherence of organizations’ utilization of HR recruitment, training and performance management policies to support and enhance firms’ innovation performance. Through a social–psychological perspective, we situate our findings in two diverse areas: the psychological literature, exploring the measurement of innovation, and second, with regard to the internal (with each other) and external (with broader organizational objectives) integration of distinct HR policy elements. Our surveyed organizations indicate that, whilst attaching importance to innovation, they fail to consistently translate this importance into coherent HR policies. Typically, HR policy rewarded non-managerial employees for innovation, whilst managerial staff were expected to do so as a matter of course. This inconsistency is one source of resistance which blocks the generation of new ideas, and their implementation, organization-wide