457 research outputs found
The Study on RFID Security Method for Entrance Guard System
The RFID technology has been used by industries in recent years, for examples, replacing the traditional two-dimensional barcode, logistics management, military applications, identification. In fact, RFID technology has become one of the new killer technologies. The RFID uses radio frequency to convey information which involves, however, many security problems; Current RFID guidelines do not present solutions to these security problems. The methods put forward in published paper fail to offer complete solutions, either. This study identifies RFID security method for Entrance Guard system. The algorithms used include Hash, AES, random values, XOR four item technology, and use the three-way authentication structure to solve the safety problems of the certification of Entrance Guard system. The experiment showed the algorithms provided better protection on the current RFID systems against attack methods such as Eavesdropping, Traceability, Spoofing and Replay attacking
Photoresponsive and Ultraviolet to Visible-Light Range Photocatalytic Properties of ZnO:Sb Nanowires
100學年度研究獎補助論文[[abstract]]Zinc oxide (ZnO) doped antimony (Sb) nanowires have been synthesized for improving ultraviolet sensing and photocatalytic properties. Upon illumination by UV light (365nm , 2.33mWcm−2 ), the photoelectric current of the ZnO:Sb nanowires exhibited a rapid photoresponse as compared to that of the ZnO nanowires. A highest ratio of photocurrent to dark current of around 48.8-fold was achieved in the as-synthesized ZnO:Sb nanowires. A UV-visible spectrophotometer was used to investigate the absorbance spectrum of the ZnO:Sb nanowires, which exhibited a high absorbance ratio with redshift effect in contrast to that of the ZnO nanowires. Visible-light photocatalysis and UV photoresponsive properties of the ZnO:Sb nanowires are superior to those of the ZnO nanowires.[[notice]]補正完畢[[incitationindex]]SCI[[booktype]]電子
The quantum cryptographic switch
We illustrate using a quantum system the principle of a cryptographic switch,
in which a third party (Charlie) can control to a continuously varying degree
the amount of information the receiver (Bob) receives, after the sender (Alice)
has sent her information. Suppose Charlie transmits a Bell state to Alice and
Bob. Alice uses dense coding to transmit two bits to Bob. Only if the 2-bit
information corresponding to choice of Bell state is made available by Charlie
to Bob can the latter recover Alice's information. By varying the information
he gives, Charlie can continuously vary the information recovered by Bob. The
performance of the protocol subjected to the squeezed generalized amplitude
damping channel is considered. We also present a number of practical situations
where a cryptographic switch would be of use.Comment: 7 pages, 4 Figure
Improved protocols of secure quantum communication using W states
Recently, Hwang et al. [Eur. Phys. J. D. 61, 785 (2011)] and Yuan et al.
[Int. J. Theo. Phys. 50, 2403 (2011)] have proposed two efficient protocols of
secure quantum communication using 3-qubit and 4-qubit symmetric W state
respectively. These two dense coding based protocols are generalized and their
efficiencies are considerably improved. Simple bounds on the qubit efficiency
of deterministic secure quantum communication (DSQC) and quantum secure direct
communication (QSDC) protocols are obtained and it is shown that dense coding
is not essential for designing of maximally efficient DSQC and QSDC protocols.
This fact is used to design maximally efficient protocols of DSQC and QSDC
using 3-qubit and 4-qubit W states.Comment: 8 page
Urban-rural disparity of preventive healthcare utilisation among children under the universal health insurance coverage in Taiwan: a national birth cohort analysis
Objective: In the context of universal health insurance coverage, this study aimed to determine whether urbanerural inequality still exists in preventive health care (PHC) amongst children in Taiwan. Study design: Prospective cohort study. Methods: A total of 184,117 mothers and their children born in 2009 were identified as the study cohort. The number of children born in urban, satellite and rural areas was 40,176, 57,565 and 86,805, respec-tively. All children were followed for 7 years, before which a total of seven times PHC were provided by Taiwan's National Health Insurance (NHI) programme. Ordinal logistic regression models were used to associate urbanisation level with the frequency of PHC utilisation. Stratified analyses were further per-formed in accordance with the children's birth weight and the mothers' birthplace. Results: Children from satellite areas had higher utilisation for the first four scheduled PHC visits. Children living in urban areas received more PHC for the fifth and sixth scheduled visits. Compared with those from rural areas, children in satellite areas exhibited a small but significant increase in odds in PHC utilisation, with a covariate-adjusted odds ratio (aOR) of 1.04 and 95% confidence interval (CI) of 1.02 e1.06. By contrast, no significant difference was observed between rural and urban areas (aOR ¼ 1.01). Further stratified analyses suggest more evident urbanerural difference in PHC utilisation amongst children with low birth weight and foreign-born mothers. Conclusions: Given a universal health insurance coverage and embedded mechanisms in increasing the availability of healthcare resources in Taiwan, a slight urbanerural difference is observed in PHC uti-lisation amongst children. Hence, sociodemographic inequality in utilisation of PHC still exists. This issue should be addressed through policy intervention
Helical structure motifs made searchable for functional peptide design
The systematic design of functional peptides has technological and therapeutic applications.
However, there is a need for pattern-based search engines that help locate desired functional
motifs in primary sequences regardless of their evolutionary conservation. Existing databases
such as The Protein Secondary Structure database (PSS) no longer serves the community,
while the Dictionary of Protein Secondary Structure (DSSP) annotates the secondary
structures when tertiary structures of proteins are provided. Here, we extract 1.7 million
helices from the PDB and compile them into a database (Therapeutic Peptide Design database; TP-DB) that allows queries of compounded patterns to facilitate the identification of
sequence motifs of helical structures. We show how TP-DB helps us identify a known
purification-tag-specific antibody that can be repurposed into a diagnostic kit for Helicobacter
pylori. We also show how the database can be used to design a new antimicrobial peptide
that shows better Candida albicans clearance and lower hemolysis than its template homologs. Finally, we demonstrate how TP-DB can suggest point mutations in helical peptide
blockers to prevent a targeted tumorigenic protein-protein interaction. TP-DB is made
available at http://dyn.life.nthu.edu.tw/design/
Supermassive Black Hole Binaries: The Search Continues
Gravitationally bound supermassive black hole binaries (SBHBs) are thought to
be a natural product of galactic mergers and growth of the large scale
structure in the universe. They however remain observationally elusive, thus
raising a question about characteristic observational signatures associated
with these systems. In this conference proceeding I discuss current theoretical
understanding and latest advances and prospects in observational searches for
SBHBs.Comment: 17 pages, 4 figures. To appear in the Proceedings of 2014 Sant Cugat
Forum on Astrophysics. Astrophysics and Space Science Proceedings, ed.
C.Sopuerta (Berlin: Springer-Verlag
The NuSTAR Extragalactic Survey: A First Sensitive Look at the High-energy Cosmic X-Ray Background Population
We report on the first 10 identifications of sources serendipitously detected by the Nuclear Spectroscopic Telescope Array (NuSTAR) to provide the first sensitive census of the cosmic X-ray background source population at gsim 10 keV. We find that these NuSTAR-detected sources are ≈100 times fainter than those previously detected at gsim 10 keV and have a broad range in redshift and luminosity (z = 0.020-2.923 and L 10-40 keV ≈ 4 × 1041-5 × 1045 erg s–1); the median redshift and luminosity are z ≈ 0.7 and L 10-40 keV ≈ 3 × 1044 erg s–1, respectively. We characterize these sources on the basis of broad-band ≈0.5-32 keV spectroscopy, optical spectroscopy, and broad-band ultraviolet-to-mid-infrared spectral energy distribution analyses. We find that the dominant source population is quasars with L 10-40 keV > 1044 erg s–1, of which ≈50% are obscured with N H gsim 1022 cm–2. However, none of the 10 NuSTAR sources are Compton thick (N H gsim 1024 cm–2) and we place a 90% confidence upper limit on the fraction of Compton-thick quasars (L 10-40 keV > 1044 erg s–1) selected at gsim 10 keV of lsim 33% over the redshift range z = 0.5-1.1. We jointly fitted the rest-frame ≈10-40 keV data for all of the non-beamed sources with L 10-40 keV > 1043 erg s–1 to constrain the average strength of reflection; we find R < 1.4 for Γ = 1.8, broadly consistent with that found for local active galactic nuclei (AGNs) observed at gsim 10 keV. We also constrain the host-galaxy masses and find a median stellar mass of ≈1011 M ☉, a factor ≈5 times higher than the median stellar mass of nearby high-energy selected AGNs, which may be at least partially driven by the order of magnitude higher X-ray luminosities of the NuSTAR sources. Within the low source-statistic limitations of our study, our results suggest that the overall properties of the NuSTAR sources are broadly similar to those of nearby high-energy selected AGNs but scaled up in luminosity and mass
Epitaxial Catalyst-Free Growth of InN Nanorods onc-Plane Sapphire
We report observation of catalyst-free hydride vapor phase epitaxy growth of InN nanorods. Characterization of the nanorods with transmission electron microscopy, and X-ray diffraction show that the nanorods are stoichiometric 2H–InN single crystals growing in the [0001] orientation. The InN rods are uniform, showing very little variation in both diameter and length. Surprisingly, the rods show clear epitaxial relations with thec-plane sapphire substrate, despite about 29% of lattice mismatch. Comparing catalyst-free with Ni-catalyzed growth, the only difference observed is in the density of nucleation sites, suggesting that Ni does not work like the typical vapor–liquid–solid catalyst, but rather functions as a nucleation promoter by catalyzing the decomposition of ammonia. No conclusive photoluminescence was observed from single nanorods, while integrating over a large area showed weak wide emissions centered at 0.78 and at 1.9 eV
Knockdown of zebrafish Nav1.6 sodium channel impairs embryonic locomotor activities
[[abstract]]Although multiple subtypes of sodium channels are expressed in most neurons, the specific contributions of the individual sodium channels remain to be studied. The role of zebrafish Nav1.6 sodium channels in the embryonic locomotor movements has been investigated by the antisense morpholino (MO) knockdown. MO1 and MO2 are targeted at the regions surrounding the translation start site of zebrafish Nav1.6 mRNA. MO3 is targeted at the RNA splicing donor site of exon 2. The correctly spliced Nav1.6 mRNA of MO3 morphants is 6% relative to that of the wild-type embryos. Nav1.6-targeted MO1, MO2 and MO3 attenuate the spontaneous contraction, tactile sensitivity, and swimming in comparison with a scrambled morpholino and mutated MO3 morpholino. No significant defect is observed in the development of slow muscles, the axonal projection of primary motoneurons, and neuromuscular junctions. The movement impairments caused by MO1, MO2, and MO3 suggest that the function of Nav1.6 sodium channels is essential on the normal early embryonic locomotor activities.[[notice]]補正完畢[[journaltype]]國
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