Excitation of surface-plasmon polaritons by use of a zeroth-order Bessel beam

We report an experimental result that shows the excitation of surface plasmon polaritons by use of a zeroth-order Bessel beam. From the viewpoint of energy efficiency, the zeroth order Bessel beam is ideal for the local excitation of surface plasmon polaritons on a metal film. We introduce an optical setup using an axicon element in order to carry out the excitation.     

High-power TE CO2laser with graphite electrodes

A high-power CW TE CO2laser using a new graphite anode structure and a novel Mo wire cathode is described. A uniform discharge for laser excitation is obtained. The device produces a CW output of 6 kW.     

Efficient frequency doubling of 1-W continuous-wave Ti:sapphire laser with a robust high-finesse external cavity

We demonstrated an intrinsic conversion efficiency of 56% from the input fundamental power to the generated second-harmonic power. The second-harmonic power of 581 mW was obtained from the external cavity with a LiB3O5 crystal through the frequency doubling of a 1.17-W Ti:sapphire laser at 746 nm, when the finesse of the robust external cavity was 260.     

Switching Phenomena between Laminar and Turbulent Flows of Superfluid 4He Generated by a Vibrating Wire

We have investigated the turbulence transition of the superfluid ⁴He flow generated by a vibrating wire. For a 1.2-kHz vibrating wire, we observed intermittent switchings between laminar and turbulent flows. The switching rate decreases with increasing temperature above 100 mK, until no occurrence of the switchings at 350 mK. For a 2.4-kHz vibrating wire, we find that the switching rate is much lower than that of the 1.2-kHz vibrating wire even at low temperatures. This result indicates that a mechanism causing the switchings is influenced by the temperature and the oscillation frequency of the superfluid flow.     

Building more solid bridges between Buddhism and Western psychology.

Introducing the ways of cultivating mental balance, B. A. Wallace and S. L. Shapiro (see record 2006-12925-003) attempted to build bridges between Buddhism and psychology. Their systematic categorization of Buddhist teachings and extensive review of empirical support from Western psychology are valuable for future study. However, it remains a matter of concern that some more profound parts of Buddhist philosophy can be disregarded by focusing only on practical aspects of Buddhism within the context of mental health. In this comment, the authors briefly address four substantial themes to be considered: reality, identity, causality, and logicality. They suggest that the way to interpret Buddhism as techniques for well-being would certainly be viable in encouraging the study of Buddhist teachings in psychology. Yet, such attempts should not result in superficial imports and applications of Buddhist practices but give due weight to the deeper philosophical issues to build more solid bridges between Buddhism and psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Self-routing planar network for guided-wave optical switching systems

An N*N self-routing planar network suitable for fabricating optical space switches on lithium niobate substrate is presented. The network has O(N/sup 2/) cross points, good modularity and expandability. It also has no waveguide crossovers and no differential attenuation between any of the input and output pairs. A self-routing control can be applied to this network, which is indispensable for ATM switching systems.<>     

Gas entrainment inception at the border of a flow-swollen liquid surface

A rapid liquid flow into a tank may impinge on the free surface, making it swell partially. The returning flow branches off from the free surface and re-submerges at the border of the swollen surface. If the flow velocity along the swollen surface is high enough, gas bubbles are formed at the border and entrained by the liquid flow. The conditions necessary for gas entrainment in a simple system are examined experimentally, using water and air as working fluids. The effect of surface tension is examined by adding a surface active agent to the water. The results show that gas entrainment inception is determined by the flow pattern in the system and the product of the Froude and Weber numbers based on the local velocity at the bubble formation point.     

An efficient contention resolution algorithm for input queuing atm cross-connect switches

This paper describes an efficient contention resolution algorithm and its distributed implementation for large capacity input queuing cross-connect switches, which will establish virtual paths in future broadband ATM networks. The algorithm dynamically allocates sending time to cells held in input queues when no contention is indicated in the designated output ports. An expression for the mean delay and the cell loss probability for random traffic are derived through an approximate analysis. Input cells are served on a first-come, first-served basis as conventional contention resolution algorithms whose throughput saturates at 58 per cent because of head of line blocking in input queues. The proposed algorithm achieves a maximum throughput of 76 per cent.     

Polonium evaporation and adhesion experiments for the development of polonium filter in lead–bismuth cooled reactors

Fundamental experiments were performed to determine the adhesion characteristics of polonium to different metals and to develop a filter for polonium evaporated from neutron-irradiated LBE. The results of the first experiments suggested that adhesion characteristics are almost the same for stainless steel and nickel metal. The results of the preliminary experiments for a polonium filter suggested that stainless steel mesh with thin wires could effectively collect polonium evaporated from neutron-irradiated LBE. In the experiments, stainless steel wire mesh was used, but from the results of adhesion experiment, it is expected that the same effect can be obtained with wire mesh made of other kinds of metal.     

Efficient parallel time-slot interchanger for high-performanceSDH/SONET digital crossconnect systems

A parallel design of time-slot interchangers is refined in order to scale the interchangers' capacity in an efficient manner. Performance analysis shows that this design scheme requires significantly less memory compared with a conventional parallel design because of newly implemented load-balancing switches, while keeping its switching control complexity to a minimum