8,575 research outputs found
Spartan Web Application Firewall
Computer security is an ongoing issue and attacks are growing more sophisit- cated. One category of attack utilizes cross-site scripting (XSS) to extract confiden- tial data such as a user’s login credential’s without the knowledge of either the user nor the web server by utilizing vulnerabilities on web pages and internet browsers. Many people develop their own web applications without learning about or having good coding practices or security in mind. Web application firewalls are able to help but can be enhanced to be more effective than they currently are at detecting re- flected XSS attacks by analyzing the request and response data sent between the web application by a user’s browser to more quickly determine if a reflected XSS attack is being attempted. Spartan Web Application Firewall is designed to do this efficiently without being limited to requiring users to be using a specific web browser or web browser plug-in
MARVELS-1b: A Short-period, Brown Dwarf Desert Candidate from the SDSS-III Marvels Planet Search
We present a new short-period brown dwarf (BD) candidate around the star TYC 1240-00945-1. This candidate was discovered in the first year of the Multi-object APO Radial Velocity Exoplanets Large-area Survey (MARVELS), which is part of the Sloan Digital Sky Survey (SDSS) III, and we designate the BD as MARVELS-1b. MARVELS uses the technique of dispersed fixed-delay interferometery to simultaneously obtain radial velocity (RV) measurements for 60 objects per field using a single, custom-built instrument that is fiber fed from the SDSS 2.5 m telescope. From our 20 RV measurements spread over a ~370 day time baseline, we derive a Keplerian orbital fit with semi-amplitude K = 2.533 ± 0.025 km s^(–1), period P = 5.8953 ± 0.0004 days, and eccentricity consistent with circular. Independent follow-up RV data confirm the orbit. Adopting a mass of 1.37 ± 0.11 M_☉ for the slightly evolved F9 host star, we infer that the companion has a minimum mass of 28.0 ± 1.5 M_(Jup), a semimajor axis 0.071 ± 0.002 AU assuming an edge-on orbit, and is probably tidally synchronized. We find no evidence for coherent intrinsic variability of the host star at the period of the companion at levels greater than a few millimagnitudes. The companion has an a priori transit probability of ~14%. Although we find no evidence for transits, we cannot definitively rule them out for companion radii ≲ R_(Jup)
What affects commute cycling in Sydney: Access, infrastructure and demographics
A better understanding of factors affecting commute cycling will be needed to affect a greater uptake of active transport in many parts of the world, and to facilitate the shift toward more sustainable cities. Commute cycling rates in Sydney is currently low; in this paper we use census data and aggregate level attributes to identify factors affect- ing commute cycling in Sydney, Australia, including (i) road and cycling infrastructure; (ii) the convenience of reaching destinations by cycling (access); and (iii) demographic variables. We find places with high commute cycling levels consistently have good ac- cess to jobs and to cycling infrastructure. Student population has a positive effect on commute cycling rates while areas in the city with a high proportion of East Asian population has a negative effect. This paper highlights the importance of providing cy- cling infrastructure in conjunction with job accessibility in order to encourage commute cycling. Active transport policies should aim to promote commute cycling in historical CBD, and focus on recreational or non-commuting utility cycling in local centers and suburban areas
Lasers incorporating two-dimensional photonic crystal mirrors
Photonic bandgap crystals are expected to be
of use in defining microcavities for modifying
spontaneous emission and as highly reflective
mirrors. There are several reports of microfabricating
one-dimensional structure. Here, we describe the incorporation of a microfabricated two-dimensional photonic lattice in an edge-emitting semiconductor laser structure.
We demonstrate laser operation in a cavity formed between a cleaved facet and a microfabricated periodic lattice
A Nonclassical Dihydrogen Adduct of S = ½ Fe(I)
We have exploited the capacity of the “(SiP^(iPr)_3)Fe(I)” scaffold to accommodate additional axial ligands and characterized the mononuclear S = 1/2 H_2 adduct complex (SiP^(iPr)_3)Fe^I(H_2). EPR and ENDOR data, in the context of X-ray structural results, revealed that this complex provides a highly unusual example of an open-shell metal complex that binds dihydrogen as a ligand. The H2 ligand at 2 K dynamically reorients within the ligand-binding pocket, tunneling among the energy minima created by strong interactions with the three Fe–P bonds
AdS/QHE: Towards a Holographic Description of Quantum Hall Experiments
Transitions among quantum Hall plateaux share a suite of remarkable
experimental features, such as semi-circle laws and duality relations, whose
accuracy and robustness are difficult to explain directly in terms of the
detailed dynamics of the microscopic electrons. They would naturally follow if
the low-energy transport properties were governed by an emergent discrete
duality group relating the different plateaux, but no explicit examples of
interacting systems having such a group are known. Recent progress using the
AdS/CFT correspondence has identified examples with similar duality groups, but
without the DC ohmic conductivity characteristic of quantum Hall experiments.
We use this to propose a simple holographic model for low-energy quantum Hall
systems, with a nonzero DC conductivity that automatically exhibits all of the
observed consequences of duality, including the existence of the plateaux and
the semi-circle transitions between them. The model can be regarded as a
strongly coupled analog of the old `composite boson' picture of quantum Hall
systems. Non-universal features of the model can be used to test whether it
describes actual materials, and we comment on some of these in our proposed
model.Comment: LaTex 52 pages 11 figures. Repost improves the discussion of the
probe approximation; corrects minor errors; adds references. Second repost
generalizes charged solution and improves scaling discussio
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