Waveguide-modulated surface plasmon-coupled emission of Nile blue in poly(vinyl alcohol) thin films

Surface plasmon-coupled emission (SPCE) phenomenon is the coupling of excited fluorophores near a silver film with surface plasmons, resulting in directional emission into the underlying glass substrates. We report a complex coupling of Nile Blue fluorophore with 50 nm silver mirror, resulting in emission at several angles in the glass substrate, with either s or p polarization. This complex pattern of directional and polarized emission appears to be due to optical waveguide effects occurring when the sample thickness becomes comparable to the emission wavelength. We expect waveguide-modulated SPCE to have applications to biophysics and sensing.     

Load-Balanced Location Management for Cellular Mobile Systems Using Quorums and Dynamic Hashing

This paper presents a new distributed location management strategy for cellular mobile systems. Its salient features are fast location update and query, load balancing among location servers, and scalability. The strategy employs dynamic hashing techniques and quorums to manage location update and query operations. The proposed strategy does not require a home location register (HLR) to be associated with each mobile node. Location updates and queries for a mobile node are multicast to subsets of location servers, which change with time depending on the location of mobile node/querying node and load on the servers. Simulation experiments demonstrate that such dynamism prevents situations of heavy load on some location servers when mobile nodes are not uniformly distributed in space, or when some mobile nodes have their location updated or queried more often than others. Also, queries return the latest location information of a mobile node with a very high probability. The proposed scheme requires at most one unicast and two rounds of message multicasting for location update and query operations. All multicast messages have a small payload and are restricted to the high bandwidth wired part of the mobile network resulting in low communication overhead. Moreover, if a quorum of location servers gets overloaded, part of its load can be transferred to another lightly loaded quorum using dynamic hashing techniques.     

Probleme und Lösungen beim Feuchtigkeitsschutz des Mauerwerks von Baudenkmälern am Beispiel zweier großer Barockbauten in Wrocław

Problems concerning damp‐proofing brick‐laid historic building – shown on the example of two huge baroque structures in Wrozław. Most brick‐laid historic buildings in Poland are in bad technological condition due to lack of proper damp and water insulations, hence they need immediate renovation. Water is the biggest enemy of building constructions, especially of historic structures. The main source of dampness in buildings is rainwater, ground capillary water and water present in humid air, absorbed by porous, hygroscopic materials. It is a difficult task to design and later effect the correct and efficient damp‐proofing, and requires specific interdisciplinary knowledge. The article describes some chosen problems that appeared in the course of designing and making damp insulations in two huge historic priceless baroque buildings situated near the Odra River in Wrocław, namely, the main building of the University of Wrocław and the building of National Ossolinski Institute in Wrocław.     

Effect of production season on protein fraction content in milk of various breeds of goats in Poland

Milk of various goat breeds was analysed to assess the effect of production season on content of basic chemical components, with regard to whey proteins. Milk of goats in the productive herds (white and coloured coat) contained significantly (P < 0.01) more total protein, casein, fat, dry matter and functional whey proteins. The production season significantly determined the content of total protein (P < 0.01), casein (P < 0.01) and whey proteins (P < 0.05), including α‐lactalbumin (P < 0.01) and lactoferrin (P < 0.01). A higher content of total protein and casein was found in the autumn–winter season and the content of whey proteins was higher in the spring–summer period.     

Cost-Effective Frequency Planning for Capacity Enhancement of Femtocellular Networks

The femto-access-point, a low-cost and small-size cellular base-station, is envisioned to be widely deployed in subscribers homes, as to provide high data-rate communications with improved quality of service. As femtocellular networks will co-exist with macrocellular networks, mitigation of the interference between these two network types is a key challenge for successful integration of these two technologies. In particular, there are several interference mechanisms between the femtocellular and the macrocellular networks, and the effects of the resulting interference depend on the density of femtocells and the overlaid macrocells in a particular coverage area. While improper interference management can cause a significant reduction in the system capacity and can increase the outage probability, effective and efficient frequency allocation among femtocells and macrocells can result in a successful co-existence of these two technologies. Furthermore, highly dense femtocellular deployments—the ultimate goal of the femtocellular technology—will require significant degree of self-organization in lieu of manual configuration. In this paper, we present various femtocellular network deployment scenarios, and we propose a number of frequency-allocation schemes to mitigate the interference and to increase the spectral efficiency of the integrated network. These schemes include: shared frequency band, dedicated frequency band, sub-frequency band, static frequency-reuse, and dynamic frequency-reuse. We derive an analytical model, which allows us to analyze in details the users outage probability, and we compare the performance of the proposed schemes using numerical analysis.     

The role of interfacial energy in the wear of polymeric journal bearings

Experimental and theoretical relationships between the adhesional energy and the wear rate of a polymer, in the form of a miniature journal bearing for a steel shaft, are presented. Formulae are derived that can be used to predict the wear rate of a polymeric material in such bearings.     

Z-bunionectomy: retrospective long-term study

Long-term patient satisfaction and objective clinical and radiographic examinations of patients who had undergone the Z-bunionectomy at the University of Chicago Medical Center were evaluated. Fifty-six surgeries were performed on 31 patients, with a follow-up range of 5 to 9 years. The University of Maryland 100-Point Painful Foot Center Scoring System was modified to be more specific to bunion surgery, and we used this modification to measure patient satisfaction. Patient satisfaction was rated good to excellent by 90% of the patients. Radiographic findings included: intermetatarsal angle-mean, 7.1 degrees; hallux abductus angle-mean, 8.96 degrees; tibial sesamoid position-mean, 2.8. The mean protrusion was -1.64 mm. Radiographic findings consistent with osteonecrosis were noted of one patient, one foot, although the patient was clinically asymptomatic. The objective findings were as follows: dorsiflexion, mean, 60 degrees; plantarflexion, mean, 14 degrees. No patients had pain or crepitus, nor were they tract-bound in their first metatarsophalangeal joint range of motion. In addition, stance dorsiflexion had a mean of 21 degrees, and the purchase power was 88% good to excellent on plantar paper pull-out testing. First ray motion qualitatively demonstrated 1 1/2 to 2 times dorsiflexion to plantarflexion. There were no subsecond metatarsal head keratoses. Generalized ligamentous laxity was not seen. For the resting calcaneal stance position the mean was 3.5 degrees everted, with 24% of the patients maximally pronated in this position. We were unable to correlate any structural and functional postoperative features with patient satisfaction.     

Numerical modelling of heat transfer processes with supplementary data

Mathematical models of heat transfer processes are usually studied using formulation that is unique in the mathematical sense. For example, in solving initial-boundary value problems in conduction heat transfer, the mathematical model consists of the governing equation and initial and boundary conditions. An extension of such an approach by introducing the supplementary information (or data) concerning the process has been proposed here as a method for verifying the accuracy of the model equations. This means that the mathematical model consists of more equations than unknowns which leads in consequence to a finite set of probable solutions. A criterion for choosing the most probable solution has been proposed. Special attention has been paid to numerical formulation. Computational methods have been derived using the Lagrange multipliers. Theoretical considerations have been illustrated by computing the temperature distribution inside a laboratory combustion chamber.     

On optimizing the location update costs in the presence of database failures

This paper studies the database failure recovery procedure for cellular phone networks as part of the Electronic Industries Association/Telecommunications Industry Association Interim Standard 41 (EIA/TIA IS-41). Before the location information of the database is recovered, phone calls may be lost. The restoration process can be sped up by having the mobile phones to periodically confirm their existence by radio contact with the cellular network. We show that, under some cost assumptions, periodic update interval should be chosen to be approximately equal to the call interarrival time, with more frequent updates for more unreliable system. We also show that the cost of an optimized system is relatively small and stable, if the system is even moderately reliable. Finally, if the system is at least moderately reliable, the effects of call origination rate and the rate at which Location Areas are crossed, are rather small, assuming that the periodic update interval was chosen as stated above. Thus, in such cases, optimization of the size of the Location Area can be made independent of the optimization of the periodic update process.     

Optimal Sequential Paging in Cellular Wireless Networks

In a high-capacity cellular network with limited spectral resources, it is desirable to minimize the radio bandwidth costs associated with paging when locating mobile users. Sequential paging, in which cells in the coverage area are partitioned into groups and paged in a non-increasing order of user location probabilities, permits a reduction in the average radio costs of paging at the expense of greater delay in locating the users. We present a polynomial time algorithm for minimizing paging cost under the average delay constraint, a problem that has previously been considered intractable. We show the conditions under which cluster paging, a simple heuristic technique proposed for use with dynamic location update schemes, is optimal. We also present analytical results on the average delay and paging cost obtained with sequential paging, including tight bounds.