639 research outputs found
A Cloud Platform-as-a-Service for Multimedia Conferencing Service Provisioning
Multimedia conferencing is the real-time exchange of multimedia content
between multiple parties. It is the basis of a wide range of applications
(e.g., multimedia multiplayer game). Cloud-based provisioning of the
conferencing services on which these applications rely will bring benefits,
such as easy service provisioning and elastic scalability. However, it remains
a big challenge. This paper proposes a PaaS for conferencing service
provisioning. The proposed PaaS is based on a business model from the state of
the art. It relies on conferencing IaaSs that, instead of VMs, offer
conferencing substrates (e.g., dial-in signaling, video mixer and audio mixer).
The PaaS enables composition of new conferences from substrates on the fly.
This has been prototyped in this paper and, in order to evaluate it, a
conferencing IaaS is also implemented. Performance measurements are also made.Comment: 6 pages, 6 figures, IEEE ISCC 201
Single shot ultrafast all optical magnetization switching of ferromagnetic Co/Pt multilayers
In a number of recent experiments, it has been shown that femtosecond laser
pulses can control magnetization on picosecond timescales, which is at least an
order of magnitude faster compared to conventional magnetization dynamics.
Among these demonstrations, one material system (GdFeCo ferromagnetic films) is
particularly interesting, as deterministic toggle-switching of the magnetic
order has been achieved without the need of any symmetry breaking magnetic
field. This phenomenon is often referred to as all optical switching (AOS).
However, so far, GdFeCo remains the only material system where such
deterministic switching has been observed. When extended to ferromagnetic
systems, which are of greater interest in many technological applications, only
a partial effect can be achieved, which in turn requires repeated laser pulses
for full switching. However, such repeated pulsing is not only energy hungry,
it also negates the speed advantage of AOS. Motivated by this problem, we have
developed a general method for single-shot, picosecond timescale, complete all
optical switching of ferromagnetic materials. We demonstrate that in
exchange-coupled layers of Co/Pt and GdFeCo, single shot, switching of the
ferromagnetic Co/Pt layer is achieved within 7 picoseconds after irradiation by
a femtosecond laser pulse. We believe that this approach will greatly expand
the range of materials and applications for ultrafast magnetic switching.Comment: 11 pages, 3 figures, supplementary material
Pembuatan Aplikasi Sistem Informasi Persebaran Toko Batik Di Kota Pekalongan Berbasis Android
Pekalongan is located in the lowlands along the north coast of Java Island, at a height of approximately one meter above sea level. The geographical position of Pekalongan is between 6° 50\u27 42" to 6° 55\u27 44\u27\u27 North Latitude and 109° 37\u27 55\u27\u27to 109° 42\u27 19\u27\u27 East Longitude.Pekalongan area of about 42.25 km2 or approximately 0.14% from the area of Central Java Province.Pekalongan is known by the nickname city of Batik, because batik Pekalongan has distinctive and varied livery. Therefore, Pekalongan is espected to provide a practical and informative information for tourists, so it can be an attraction and increase the number of tourists coming to Pekalongan. This research uses of spatial and non spasial data in the form of batik store name, the owner\u27s name, phone number, address, and products sold with using the popularity of android smartphone as a platform system information.This application was developed using an SDK Andoidframework, java and PHP programming languages, and MySQL as base data, and Google Maps. The final result of this research is the Android application of the distribution of batik store in Pekalongan is accompanied by information (as has been mentioned above) from each store for easier searching the location of the batik stores in Pekalonga
Disain dan Simulasi Rangkaian Detektor Detak Jantung Janin Menggunakan Teknologi Cmos 0.35m
Rangkaian detektor detak jantung janin telah berhasil dirancang denganmenggunakan teknologi CMOS 0.35um. Hasil simulasi menunjukan bahwarangkaian detektor ini dapat mendeteksi frekuensi 2 sampai 3 hz. Rangkaian inisiap di realisasikan sebagai detektor detak jantung janin
Gaschromatography/mass spectrometry analysis of degradation of ethylacetoacetate achieved in shake flask culture using a previously characterized yeast strain Tichosporon dermatis.
Public and regulatory interest regarding the presence of pharmaceutically active compounds in the environment its increasing adverse impact has increased in the recent years. Detection of a wide variety of pharmaceutical compounds in water environment has been a serious and growing concern in the last few decades. Understanding the biological degradation of pharmaceutical compounds is essential for accurately determining their ultimate environmental fate, conducting accurate risk assessments, and improving removal of such micro pollutants. Present investigation was designed to accomplish biodegradation of ethylacetoacetate in shake flask culture using whole cells of previously isolated and identified yeast strain Trichosporon dermatis, from pharmaceutical effluents using enrichment culture technique. The strain was cultivated for two generations on an orbital shaker at 120 rpm at 28 ± 20C and the biomass was separated by centrifugation at 10,000 rpm for 20 mts. Normal saline washed cells were used in degradation carried out in Erlenmeyer flasks containing 500 ml of mineral medium containing ethylacetoacetate at standard conditions; wet cell weight= 20g/l; ethylacetoacetate concentration = 0.5% in mineral medium (w/v); time of biodegradation= 72 hrs; temperature= 28 ± 20C. Gas chromatography/mass spectrometry (GC-MS) analysis of microbially degraded product revealed that complete degradation of ethylacetoacetate in mineral medium was achieved in 72 hours using whole cells of Trichosporon dermatis yeast strain. Degradation of ethylacetoacetate by this yeast strain has not been reported before the present investigation. Keywords: ethyl acetoacetate, biodegradation, Gass chromatography/mass spectrometry and effluents
A Low-cost Method to Identify Tubewells for Longitudinal Research on Arsenic in Groundwater
Exposure to high concentrations of arsenic in tubewell groundwater from the shallow aquifers of Bangladesh could result in up to 300,000 arsenic-related cancer cases over the next four decades. Understanding the magnitude and temporal dynamics of this exposure, via longitudinal studies, is imperative for planning effective mitigation and management strategies. Appropriate methods are needed to identify tubewells for longitudinal sampling. A plastic band marked with a unique identification number was developed, and various methods for attaching the band to the tubewell were tested, resulting in the choice of a galvanized-iron split-rivet. Two follow-up surveys at two and 14 months post-banding assessed the durability and longevity under field conditions in the JiVitA Project area in rural, northwestern Bangladesh. After two months, ~96.0% of the original bands on 1,063 tubewells were functional, although the rivets were partially corroded. After 14 months, ~65% of a subsample of the bands were functional. With further improvements to the rivets, these bands offer an inexpensive, durable, enumeration technology for longitudinal studies on groundwater arsenic
Carbonaceous Materials Coated Carbon Fibre Reinforced Polymer Matrix Composites
Carbon fibre reinforced polymer composites have high mechanical properties that make them exemplary engineered materials to carry loads and stresses. Coupling fibre and matrix together require good understanding of not only fibre morphology but also matrix rheology. One way of having a strongly coupled fibre and matrix interface is to size the reinforcing fibres by means of micro- or nanocarbon materials coating on the fibre surface. Common coating materials used are carbon nanotubes and nanofibres and graphene, and more recently carbon black (colloidal particles of virtually pure elemental carbon) and graphite. There are several chemical, thermal, and electrochemical processes that are used for coating the carbonous materials onto a carbon fibre surface. Sizing of fibres provides higher interfacial adhesion between fibre and matrix and allows better fibre wetting by the surrounded matrix material. This review paper goes over numerous techniques that are used for engineering the interface between both fibre and matrix systems, which is eventually the key to better mechanical properties of the composite systems
Salt-induced inhibition of the precipitin reaction of concanavalin A with polysaccharides and glycoprotein
Geographic variation in access to dog-bite care in Pakistan and risk of dog-bite exposure in Karachi: prospective surveillance using a low-cost mobile phone system
Background: Dog-bites and rabies are under-reported in developing countries such as Pakistan and there is a poor understanding of the disease burden. We prospectively collected data utilizing mobile phones for dog-bite and rabies surveillance across nine emergency rooms (ER) in Pakistan, recording patient health-seeking behaviors, access to care and analyzed spatial distribution of cases from Karachi. Methodology and Principal: Findings A total of 6212 dog-bite cases were identified over two years starting in February 2009 with largest number reported from Karachi (59.7%), followed by Peshawar (13.1%) and Hyderabad (11.4%). Severity of dog-bites was assessed using the WHO classification. Forty percent of patients had Category I (least severe) bites, 28.1% had Category II bites and 31.9% had Category III (most severe bites). Patients visiting a large public hospital ER in Karachi were least likely to seek immediate healthcare at non-medical facilities (Odds Ratio = 0.20, 95% CI 0.17–0.23, p-value<0.01), and had shorter mean travel time to emergency rooms, adjusted for age and gender (32.78 min, 95% CI 31.82–33.78, p-value<0.01) than patients visiting hospitals in smaller cities. Spatial analysis of dog-bites in Karachi suggested clustering of cases (Moran's I = 0.02, p value<0.01), and increased risk of exposure in particular around Korangi and Malir that are adjacent to the city's largest abattoir in Landhi. The direct cost of operating the mHealth surveillance system was USD 7.15 per dog-bite case reported, or approximately USD 44,408 over two years. Conclusions: Our findings suggest significant differences in access to care and health-seeking behaviors in Pakistan following dog-bites. The distribution of cases in Karachi was suggestive of clustering of cases that could guide targeted disease-control efforts in the city. Mobile phone technologies for health (mHealth) allowed for the operation of a national-level disease reporting and surveillance system at a low cost.publishedVersio
A Sensitive Quantification of HHV-6B by Real-time PCR
Human herpesvirus (HHV)-6B is a pathogen causing latent infection in virtually all humans. Nevertheless, the interaction of HHV-6B with its host cells is poorly understood. Although HHV-6B is approximately 90% homologous to HHV-6A, it expresses certain B-specific genes. In order to quantify the amount of expressed viral mRNA we have developed a method using real-time PCR on a LightCycler instrument. Here we describe an assay for the detection of the HHV-6B B6 mRNA, but our approach can easily be extended to involve other mRNAs. This method is useful during the study of HHV-6B biology and offers reliable and reproducible, quantitative detection of viral mRNA below the attomol range
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