Difference Values (difference + value)

Distribution by Scientific Domains


Selected Abstracts


Burst scheduling for differentiated services in optical burst switching WDM networks

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 2 2004
David Q. Liu
Abstract Optical burst switching (OBS) is one of the most important switching technologies for future optical wavelength division multiplexing (WDM) networks and the Internet. The model of differentiated services has been proposed to support quality of service (QoS) in the IP-based Internet. It is also very important to have differentiated service support in OBS networks. When the burst scheduling in an OBS network is set up appropriately, network can support differentiated services. In this paper, we proposed a new burst scheduling scheme, called differentiated scheduling with identical priority offset time (DSIPO). In DSIPO, the same priority offset time is used for all the bursts destined to the same edge node regardless of their priorities. Differentiated services in terms of burst loss probability are achieved by processing the control packets of higher priority class bursts, thus reserving resources for their data bursts, more promptly upon their arrival than those of lower priority class bursts. Each intermediate (core) node can adjust the burst loss probabilities of various burst classes by choosing its own differentiated processing delay value for each priority class or its own differentiated processing delay difference value between any pair of adjacent priority classes. We model and analyse DSIPO in terms of the burst loss probability for each priority class with simulation validation. The performance of DISPO is evaluated by simulation. Copyright © 2004 John Wiley & Sons, Ltd. [source]


Phylogeny, biogeography and the stepwise evolutionary colonization of intertidal habitat in the Liparocephalini based on morphological and molecular characters (Coleoptera: Staphylinidae: Aleocharinae)

CLADISTICS, Issue 4 2010
Kee-Jeong Ahn
A phylogenetic analysis of the tribe Liparocephalini Fenyes is presented based on morphological and molecular characters. The data set comprised 50 adult morphological characters, partial COI (907 bp), COII (366 bp) and 12S rDNA (325,355 bp), and nearly complete sequences of 18S rDNA (1768,1902 bp) for 21 species. Eighteen species of liparocephaline beetles from all eight genera and three outgroups, are included. The sequences were analysed separately and simultaneously with morphological characters by direct optimization in the program POY4 and by partitioned Bayesian analysis for the combined data. The direct optimization (DO) tree for the combined data under equal weighting, which also shows a minimum incongruence length difference value, resulted in a monophyletic Liparocephalini with the following patterns of phylogenetic relationships (outgroup ((Baeostethus, Ianmoorea) (Paramblopusa ((Amblopusa, Halorhadinus) (Liparocephalus, Diaulota))))). A sensitivity analysis using 16 different parameter sets for the combined data shows the monophyly of the liparocephalines and all its genera under all parameter sets. Bayesian analysis resulted in topological differences in comparison with the DO tree under equal weighting only in the position of the genus Paramblopusa and clade (Amblopusa + Halorhadinus), which were reversed. Historical biogeography and the stepwise evolutionary colonization of intertidal habitat in the Liparocephalini are discussed. Based on the biogeographical analyses, we hypothesize that the ancestor of the Liparocephalini occurred along the Panthallassan Ocean, the direct antecedent of the Pacific Ocean, followed by repeated dispersals to the Nearctic from the Palearctic. We also hypothesize that ancestors of the Liparocephalini appear to have arisen in the littoral zone of beaches and then colonized rocky reef areas in the low tidal zone later through high- to mid-tide zones. ,© The Willi Hennig Society 2009. [source]


H.264/AVC baseline profile to MPEG-4 visual simple profile transcoding to reduce the spatial resolution

INTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 1 2006
Jae-Ho Hur
Abstract In this study, we propose a heterogeneous transcoding method of converting an H.264/Advanced video coding (AVC) Baseline profile (BP) video bitstream into an MPEG-4 Visual simple profile (VSP) video bitstream. The proposed method reduces the spatial resolution for mobile terminals, which support only low resolution video bitstreams. When the H.264/AVC BP video bitstream is transformed into the MPEG-4 VSP video bitstream, the conversions between the H.264/AVC BP block types and the MPEG-4 VSP block types are performed by analyzing the macroblocks (MBs) conversion probability and calculating the difference values of motion vector. The proposed transcoding method runs on average 5.5 times faster than the cascaded transcoding methods, for a degradation of the PSNR (peak-signal-to ratio) of less than 0.5 dB. © 2006 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 16, 24,33, 2006 [source]


Does diagnostic sonography alter thyroid and parathyroid hormone levels?

JOURNAL OF CLINICAL ULTRASOUND, Issue 1 2008
Erdinc Serin MD
Abstract Purpose To investigate possible alterations in the levels of thyroid and parathyroid hormones (PTHs) and thyroglobulin (TG) in healthy individuals following diagnostic sonographic examination of the thyroid gland. Methods Thirty healthy women with no pathologic findings underwent sonographic examination, followed 6 weeks later by a second examination involving a probe-only application (PA) with the ultrasound scanner switched off. Duration times were identical for both examinations. Blood was drawn before and after the 2 applications. Thyroid hormone, PTH, and TG levels before and after the 2 applications were compared, and the difference between the variations for each parameter in the first and second applications was assessed. Blood samples were taken before and after the sonographic examination and the PA, and the serum concentrations of sensitive thyrotropin, total and free thyroxine, total and free tri-iodothyronine, TG, and PTH were measured. The pre- and post-examination levels of the hormones for the 2 applications were then compared and the difference between the variations for each parameter in the first and second application was then assessed. Results The only significant variations observed were in the TG levels after PA and PTH levels after both sonographic examination and PA. The comparison between the 2 difference values revealed no significant difference except for PTH. Conclusion This preliminary report on the possible influence of sonographic examination of the thyroid on the serum levels of thyroid and parathyroid hormones suggests that gland secretions such as PTH may be affected by external factors, including ultrasound. Clinicians should be aware of alterations in hormone levels by external factors. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2008 [source]


Determining the dependence of colour values on yarn structure

COLORATION TECHNOLOGY, Issue 3 2008
Mehmet Ozturk
The colour values of knitted cotton fabrics made from single and plied ring and compact yarns were investigated before and after dyeing. The fabric samples were knitted under the same constructional properties and then dyed with direct and reactive dyes. It was found that fabrics with ring yarns had high lightness and low chroma and colour strength values compared with fabrics with compact yarns. Also colour strength and colour difference values of dyed fabrics were assessed after increasing abrasion cycles (2500, 5000, 7500 and 10 000). The main changes in colour strength values were observed at 2500 abrasion cycles. The effect of abrasion on colour difference values of fabrics having ring yarns was more obvious than fabrics having compact yarns. [source]


Colorant formulation based on new two-constant theory

COLORATION TECHNOLOGY, Issue 4 2007
Guoxing He
A new two-constant theory for colour matching has been developed based on the Kubelka,Munk theory. Colorant formulations and algorithms for matching tristimulus, K/S and reflectance values of a standard are presented based on the new theory. The algorithms are suitable for a single-constant theory as well as a two-constant theory. The experimental data show that the recipes predicted by the new two-constant theory are closer to the actual recipes of the standard sample than the recipes predicted by the single-constant theory, and also show smaller colour difference values for some disperse dyes. The results show that the scattering of some disperse dyes cannot be negligible, and that the recipes that match to textiles coloured by these disperse dyes should be predicted using the new two-constant theory. [source]