Applying the selective Cu electroplating technique to light-emitting diodes

[[abstract]]We successfully fabricated a predefined patterned copper (Cu) substrate for thin GaN light-emitting diodes without barriers by the selective electroplating technique. The contours of Cu bumps fabricated using different electroplating modes and parameters were measured. We observed that the average thickness diminished with increasing current density. The current density conditions to obtain the best upright structure in the process were 40 and 80 mA/cm2.[[notice]]補正完畢[[incitationindex]]SCI[[booktype]]紙本[[booktype]]電子

The age of the ‘Anosovka-Tel’manskaya Culture’ and the issue of a late Streletskian at Kostёnki 11, SW Russia

Triangular, concave-base ‘Streletskian points’ are documented in several assemblages from the Kostёnki complex of Upper Palaeolithic sites in south-western Russia. Some of these assemblages have been argued to evidence very early modern human occupation of Eastern Europe. However, Streletskian points are also recorded from younger contexts, notably at Kostёnki 11, where examples are attributed both to Layer V and the stratigraphically higher Layer III. The apparent relatively young age of Layer III has led some to view it as the latest manifestation of the Streletskian, although its assemblage has also been compared to the non-Streletskian Layer I of Kostёnki 8, with the two described together as the Anosovka-Tel’manskaya Culture. Radiocarbon dates of 24–23,000 bp (c. 28,500–27,000 cal bp) for a wolf burial associated with Layer III of Kostёnki 11 confirm the layer as younger than other Streletskian assemblages at Kostёnki. New radiocarbon dates for Kostёnki 8 Layer I show that the two layers are broadly contemporary, and that both are close in age to assemblages of Kostёnki’s (Late Gravettian) Kostёnki-Avdeevo Culture. In the light of these new radiocarbon dates the context of the Streletskian point from Kostёnki 11 Layer III is considered. Although firm conclusions are not possible, unresolved stratigraphic problems and the lack of technological context for this single artefact at the very least leave a question mark over its association with other material from the layer

The age of the ‘Anosovka-Tel’manskaya Culture’ and the issue of a late Streletskian at Kostёnki 11, SW Russia

Triangular, concave-base ‘Streletskian points’ are documented in several assemblages from the Kostёnki complex of Upper Palaeolithic sites in south-western Russia. Some of these assemblages have been argued to evidence very early modern human occupation of Eastern Europe. However, Streletskian points are also recorded from younger contexts, notably at Kostёnki 11, where examples are attributed both to Layer V and the stratigraphically higher Layer III. The apparent relatively young age of Layer III has led some to view it as the latest manifestation of the Streletskian, although its assemblage has also been compared to the non-Streletskian Layer I of Kostёnki 8, with the two described together as the Anosovka-Tel’manskaya Culture. Radiocarbon dates of 24–23,000 bp (c. 28,500–27,000 cal bp) for a wolf burial associated with Layer III of Kostёnki 11 confirm the layer as younger than other Streletskian assemblages at Kostёnki. New radiocarbon dates for Kostёnki 8 Layer I show that the two layers are broadly contemporary, and that both are close in age to assemblages of Kostёnki’s (Late Gravettian) Kostёnki-Avdeevo Culture. In the light of these new radiocarbon dates the context of the Streletskian point from Kostёnki 11 Layer III is considered. Although firm conclusions are not possible, unresolved stratigraphic problems and the lack of technological context for this single artefact at the very least leave a question mark over its association with other material from the layer

Retrial queue M/M/N with impatient customer in the orbit

In the paper, the retrial queueing system of M/M/N type with Poisson flow of events and impatient calls is considered. The delay time of calls in the orbit, the calls service time and the impatience time of calls in the system have exponential distribution. Asymptotic analysis method is proposed for the solving problem of finding distribution of the number of calls in the orbit under a system heavy load and long time patience of calls in the orbit condition. The theorem about the Gauss form of the asymptotic probability distribution of the number of calls in the orbit is formulated and proved. Numerical illustrations, results are also given

Retrial queueing system of MMPP/M/2 type with impatient calls in the orbit

In the paper, the retrial queueing system of MMPP/M/2 type with input MMPP-flow of events and impatient calls is considered. The delay time of calls in the orbit, the calls service time and the impatience time of calls in the orbit have exponential distribution. Asymptotic analysis method is proposed for the solving problem of finding distribution of the number of calls in the orbit under a system heavy load and long time patience of calls in the orbit condition. The theorem about the Gauss form of the asymptotic probability distribution of the number of calls in the orbit is formulated and proved. Numerical illustrations, results are also given

Distribution Parameters Estimation in Recurrent Synchronous Generalized Doubly Stochastic Flow of the Second Order

We solve the estimation problem of the probability density parameters of the inter-event interval duration in a synchronous generalized flow of the second order, which can be used as a powerful mathematical model for the arrival processes in queuing systems and networks. The explicit form of the parameter estimates is determined by the method of moments on the basis of observations of the doubly stochastic flow under the recurrence conditions that are formulated in terms of the joint probability density of the durations of two adjacent inter-event intervals. The quality of the estimates is established by using the model, reproducing the flow behavior under conditions of complete observability

Asymptotic analysis of retrial queueing system M/GI/1 with collisions and impatient calls

We consider a single-line RQ-system with collisions with Poisson arrival process; the servicing time and time delay of calls on the orbit have exponential distribution laws. Each call in orbit has the “impatience” property, that is, it can leave the system after a random time. The problem is to find the stationary distribution of the number of calls on the orbit in the system under consideration. We construct Kolmogorov equations for the distribution of state probabilities in the system in steady-state mode. To find the final probabilities, we propose a numerical algorithm and an asymptotic analysis method under the assumption of a long delay and high patience of calls in orbit. We show that the number of calls in orbit is asymptotically normal. Based on this numerical analysis, we determine the range of applicability of our asymptotic results