276 research outputs found
Local Normal Mode Coupling and Energy Band Splitting in Elliptically Birefringent 1D Magnetophotonic Crystals
An analysis is presented of wave-vector dispersion in elliptically
birefringent stratified magneto-optic media having one-dimensional periodicity.
It is found that local normal-mode polarization-state differences between
adjacent layers lead to mode coupling and impact the wave-vector dispersion and
the character of the Bloch states of the system. This coupling produces extra
terms in the dispersion relation not present in uniform circularly birefringent
magneto-optic stratified media. Normal mode coupling lifts the degeneracy at
frequency band cross-over points under certain conditions and induces a
magnetization-dependent optical band gap. This study examines the conditions
for band gap formation in the system. It shows that such a frequency-split can
be characterized by a simple coupling parameter that depends on the relation
between polarization states of local normal modes in adjacent layers. The
character of the Bloch states and conditions for maximizing the strength of the
band splitting in these systems are analyzed.Comment: 15 pages, 4 figure
A Comparative Study of Spectral Peaks Versus Global Spectral Shape as Invariant Acoustic Cues for Vowels
The primary objective of this study was to compare two sets of vowel spectral features, formants and global spectral shape parameters, as invariant acoustic cues to vowel identity. Both automatic vowel recognition experiments and perceptual experiments were performed to evaluate these two feature sets. First, these features were compared using the static spectrum sampled in the middle of each steady-state vowel versus features based on dynamic spectra. Second, the role of dynamic and contextual information was investigated in terms of improvements in automatic vowel classification rates. Third, several speaker normalizing methods were examined for each of the feature sets. Finally, perceptual experiments were performed to determine whether vowel perception is more correlated with formants or global spectral shape.
Results of the automatic vowel classification experiments indicate that global spectral shape features contain more information than do formants. For both feature sets, dynamic features are superior to static features. Spectral features spanning a time interval beginning with the start of the on-glide region of the acoustic vowel segment and ending at the end of the off-glide region of the acoustic vowel segment are required for maximum vowel recognition accuracy. Speaker normalization of both static and dynamic features can also be used to improve the automatic vowel recognition accuracy.
Results of the perceptual experiments with synthesized vowel segments indicate that if formants are kept fixed, global spectral shape can, at least for some conditions, be modified such that the synthetic speech token will be perceived according to spectral shape cues rather than formant cues. This result implies that overall spectral shape may be more important perceptually than the spectral prominences represented by the formants.
The results of this research contribute to a fundamental understanding of the information-encoding process in speech. The signal processing techniques used and the acoustic features found in this study can also be used to improve the preprocessing of acoustic signals in the front-end of automatic speech recognition systems
A study on the effect of teleworking on quality of work life
Nowadays teleworking has become a useful technique for business development and improving employees’ quality of life. Many people are now able to stay at home and do their daily job activities without bothering to wear formal closes. This paper presents an empirical investigation to study the effect of teleworking on quality of life using Walton (1976) method [Walton, R. E. (1973). Quality of working life-what is it. Sloan Management Review, 15(1), 11-21.]. The variables of quality of working-life according to Walton Model are: “Adequate and fair compensation”, “Safe and Healthy Working conditions”, “Opportunity for Continued Growth and Security”, “The Social Relevance of Work Life”, “Total Life Space”, “Social Integration in the Work”, “Constitutionalism in the work Organization”, “Human Progress Capabilities”. Using different statistical tests, the study indicate that teleworking had significant positive relationship with Quality of Working-Life components. The study also reports that different personal characteristics such as age, gender had no meaningful impact on teleworking
Incremental pattern matching for regular expressions
Graph pattern matching lies at the heart of any graph transformation-based system. Incremental pattern matching is one approach proposed for reducingthe overall cost of pattern matching over successive transformations by preserving the matches that stay relevant after a rule application. An important issue in any matching scheme, is the ability to properly and consistently deal with various facilities that add to the expressiveness of a GT-tool’s rule language. One such feature is the support for regular path expressions, which would let two nodes to be consideredas a “match”, if a certain path of edges exists between them. In this paper, the incorporation of regular expression support into incremental pattern matching is discussed within the context of the GROOVE tool set. This includes laying down a formal foundation for incremental pattern matching for regular expressions which is then used to justify the extension proposed to add regular expression support to a well-known pattern matching algorithm
Factors Associated with the Choice of Peritoneal Dialysis in Iran: Qualitative Study
BACKGROUND: Decision making about the type of dialysis in kidney failure is a matter of great importance involving the patients, his/her family, and the health care team. Identifying the factors influencing decision making for undergoing peritoneal dialysis helps the development of this therapeutic method in patients.AIM: The present study aims at explaining the factors influencing decision making about undergoing PD in ESRD patientsMETHOD: The present study is a qualitative research, which utilizes content analysis method. A semi-structured and in-depth interview was conducted with the 19 participants that selected by purposefully sampling. All interviews were recorded subsequent to receiving consent of the participants and were analyzed using content analysis method.RESULTS: The first codification process resulted in 345 codes, which finally decreased to 278 codes by continuous reading and removal of duplicates. Overall, two main categories and eight categories namely facilitating factors (viz. family atmosphere, hemodialysis problems, PD advantages, and social environment) and inhibitory factors (viz. inefficient family, PD requirements, attitudes towards hemodialysis, and the country treatment system) were selected from the total 19 sub-categories and 278 codes.CONCLUSIONS: Results indicated that various personal, family-related, psychological, social, and economic factors could affect the decision on the type of dialysis in patients. Therefore, basic infrastructures such as social support, education, and even the specialist and positive perspective of the Ministry of Health are required to choose this therapeutic method
new caerin-like antibacterial peptide from the venom gland of the Iranian scorpion Mesobuthus eupeus: cDNA amplification and sequence analysis
Scorpion venom consists of different types of peptides and proteins which are encoded by individual genes. A full length cDNA consisting of 238 base pair nucleotides and encoding 74 amino acids peptide was isolated from the venom gland of the Iranian scorpion Mesobuthus eupeus (Buthidae family). This peptide named M. eupeus caerin-like antimicrobial peptide (Me-CLAP) belonging to the group of antibacterial peptide was previously described from scorpion. In this study, sequence of cDNA encoding Me-CLAP from the M. eupeus venom glands was amplified using reverse transcriptase polymerase chain reaction (RT-PCR) and was analyzed afterwards. Me-CLAP has similar molecular characteristics to antimicrobial peptides (AMPs) of same genus like Mesobuthus martensii and M. eupeus and more differences were seen with other genus.Keywords: Caerin-like antimicrobial peptide, Mesobuthus eupeus, semi-nested real-time polymerase chain reaction
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