100 research outputs found
The New South Wales iVote System: Security Failures and Verification Flaws in a Live Online Election
In the world's largest-ever deployment of online voting, the iVote Internet
voting system was trusted for the return of 280,000 ballots in the 2015 state
election in New South Wales, Australia. During the election, we performed an
independent security analysis of parts of the live iVote system and uncovered
severe vulnerabilities that could be leveraged to manipulate votes, violate
ballot privacy, and subvert the verification mechanism. These vulnerabilities
do not seem to have been detected by the election authorities before we
disclosed them, despite a pre-election security review and despite the system
having run in a live state election for five days. One vulnerability, the
result of including analytics software from an insecure external server,
exposed some votes to complete compromise of privacy and integrity. At least
one parliamentary seat was decided by a margin much smaller than the number of
votes taken while the system was vulnerable. We also found protocol flaws,
including vote verification that was itself susceptible to manipulation. This
incident underscores the difficulty of conducting secure elections online and
carries lessons for voters, election officials, and the e-voting research
community
Modeling of solidification of MMC composites during gravity casting process
The paper deals with computer simulation of gravity casting of the metal matrix composites reinforced with ceramics (MMC) into sand mold. The subject of our interest is aluminum matrix composite (AlMMC) reinforced with ceramic particles i.e. silicon carbide SiC and glass carbon Cg. The created model describes the process taking into account solidification and its influence on the distribution of reinforcement particles. The computer calculation has been carried out in 2D system with the use of Navier-Stokes equations using ANSYS FLUENT 13. The Volume of Fluid approach (VOF) and enthalpy method have been used to model the air-fluid free surface (and also volume fraction of particular continuous phases) and the solidification of the cast, respectively
High power neon seeded JET discharges: Experiments and simulations
A series of neon seeded JET ELMy H-mode pulses is considered from the modeling as well as from the experimental point of view. For two different Ne seeding rates and two different D puffing gas levels the heating power, P heat , is in the range 22–29.5 MW. The main focus is on the numerical reconstruction of the total radiated power (which mostly depends on the W concentration) and its distribution between core and divertor and of Z eff(which mostly depends on the Ne concentration). To model self-consistently the core and the SOL two input parameters had to be adjusted case by case: the SOL diffusivity, D SOL , and the core impurity inward pinch, v pinch . D SOL had to be increased with increasing Ne and the level of v pinch had to be changed, for any given Ne , according to the level of P heat : it decreases with increasing P heat . Since the ELM frequency, f ELM , is experimentally correlated with P heat , (it increases with P heat ) the impurity inward pinch can be seen as to depend on f ELM . Therefore, to maintain a low v pinch level (i.e. high f ELM ) Ne / P heat should not exceed a certain threshold, which slightly increases with the D puffing rate. This might lead to a limitation in the viability of reducing the target heat load by Ne seeding at moderate D , while keeping Z effat acceptably low level.EURATOM 63305
Public Evidence from Secret Ballots
Elections seem simple---aren't they just counting? But they have a unique,
challenging combination of security and privacy requirements. The stakes are
high; the context is adversarial; the electorate needs to be convinced that the
results are correct; and the secrecy of the ballot must be ensured. And they
have practical constraints: time is of the essence, and voting systems need to
be affordable and maintainable, and usable by voters, election officials, and
pollworkers. It is thus not surprising that voting is a rich research area
spanning theory, applied cryptography, practical systems analysis, usable
security, and statistics. Election integrity involves two key concepts:
convincing evidence that outcomes are correct and privacy, which amounts to
convincing assurance that there is no evidence about how any given person
voted. These are obviously in tension. We examine how current systems walk this
tightrope.Comment: To appear in E-Vote-Id '1
Application of the VUV and the soft x-ray systems on JET for the study of intrinsic impurity behavior in neon seeded hybrid discharges
This paper reports on impurity behavior in a set of hybrid discharges with Ne seeding—one of the techniques considered to reduce the power load on reactor walls. A series of experiments carried out with light gas injection on JET with the ITER-Like-Wall (ILW) suggests increased tungsten release and impurity accumulation [C. Challis et al., Europhysics Conference Abstracts 41F, 2.153 (2017)]. The presented method relies mainly on the measurements collected by vacuum-ultra-violet and soft X-ray (SXR) diagnostics including the “SOXMOS” spectrometer and the SXR camera system. Both diagnostics have some limitations. Consequently, only a combination of measurements from these systems is able to provide comprehensive information about high-Z [e.g., tungsten (W)] and mid-Z [nickel (Ni), iron (Fe), copper (Cu), and molybdenum (Mo)] impurities for their further quantitative diagnosis. Moreover, thanks to the large number of the SXR lines of sight, determination of a 2D radiation profile was also possible. Additionally, the experimental results were compared with numerical modeling based on integrated simulations with COREDIV. Detailed analysis confirmed that during seeding experiments, higher tungsten release is observed, which was also found in the past. Additionally, it was noticed that besides W, the contribution of molybdenum to SXR radiation was greater, which can be explained by the place of its origin.This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014-2018
under Grant Agreement No. 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. This scientific work was partly supported by the Polish Ministry of Science and Higher Education within the framework of the scientific financial resources in the years 2014-2018 allocated for the realization of the
international co-financed project.Postprint (author's final draft
End-to-end verifiable elections in the standard model
We present the cryptographic implementation of “DEMOS”, a new e-voting system that is end-to-end verifiable in the standard model, i.e., without any additional “setup” assumption or access to a random oracle (RO). Previously known end-to-end verifiable e-voting systems required such additional assumptions (specifically, either the existence of a “randomness beacon” or were only shown secure in the RO model). In order to analyze our scheme, we also provide a modeling of end-to-end verifiability as well as privacy and receipt-freeness that encompasses previous definitions in the form of two concise attack games. Our scheme satisfies end-to-end verifiability information theoretically in the standard model and privacy/receipt-freeness under a computational assumption (subexponential Decisional Diffie Helman). In our construction, we utilize a number of techniques used for the first time in the context of e-voting schemes that include utilizing randomness from bit-fixing sources, zero-knowledge proofs with imperfect verifier randomness and complexity leveraging
Magnetic properties of exactly solvable doubly decorated Ising-Heisenberg planar models
Applying the decoration-iteration procedure, we introduce a class of exactly
solvable doubly decorated planar models consisting both of the Ising- and
Heisenberg-type atoms. Exact solutions for the ground state, phase diagrams and
basic physical quantities are derived and discussed. The detailed analysis of
the relevant quantities suggests the existence of an interesting quantum
antiferromagnetic phase in the system.Comment: 9 pages, 9 figures, submitted to Physical Review
Eyelid Disorders in Ophthalmology Practice: Results from a Large International Epidemiological Study in Eleven Countries
Purpose: Anecdotal evidence suggests that
eyelid disorders are common, although estimates of prevalence vary. The current study
determines the prevalence of eyelid disorders,
meibomian gland dysfunction (MGD) and
related diseases (specifically ocular surface disease) in a population of patients presenting for
routine ophthalmologic consultations.
Methods: This cross-sectional epidemiologic
survey evaluated patients presenting for routine
ophthalmic visits. During the consultation an
ophthalmologist completed a questionnaire,
and each patient underwent an ophthalmic
examination and completed a quality of life
questionnaire.
Results: Three hundred forty-nine ophthalmologists, recruited from 11 countries, provided data on 6525 patients. Patients were
predominantly females (61.6%). The mean age
of the study population was 57.0 ± 17.6 years.
Eyelid disorders were diagnosed in 5109 (78.3%)
patients and were statistically associated with
TFOS European Ambassador meeting: Unmet needs and future scientific and clinical solutions for ocular surface diseases
The mission of the Tear Film & Ocular Surface Society (TFOS) is to advance the research, literacy, and educational aspects of the scientific field of the tear film and ocular surface. Fundamental to fulfilling this mission is the TFOS Global Ambassador program. TFOS Ambassadors are dynamic and proactive experts, who help promote TFOS initiatives, such as presenting the conclusions and recommendations of the recent TFOS DEWS II™, throughout the world. They also identify unmet needs, and propose future clinical and scientific solutions, for management of ocular surface diseases in their countries. This meeting report addresses such needs and solutions for 25 European countries, as detailed in the TFOS European Ambassador meeting in Rome, Italy, in September 2019
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