97,626 research outputs found
3D Textured Model Encryption via 3D Lu Chaotic Mapping
In the coming Virtual/Augmented Reality (VR/AR) era, 3D contents will be
popularized just as images and videos today. The security and privacy of these
3D contents should be taken into consideration. 3D contents contain surface
models and solid models. The surface models include point clouds, meshes and
textured models. Previous work mainly focus on encryption of solid models,
point clouds and meshes. This work focuses on the most complicated 3D textured
model. We propose a 3D Lu chaotic mapping based encryption method of 3D
textured model. We encrypt the vertexes, the polygons and the textures of 3D
models separately using the 3D Lu chaotic mapping. Then the encrypted vertices,
edges and texture maps are composited together to form the final encrypted 3D
textured model. The experimental results reveal that our method can encrypt and
decrypt 3D textured models correctly. In addition, our method can resistant
several attacks such as brute-force attack and statistic attack.Comment: 13 pages, 7 figures, under review of SCI
Regioselective trans-Carboboration of Propargyl Alcohols
Proper choice of the base allowed trans-diboration of propargyl alcohols with B2(pin)2 to evolve into an exquisitely regioselective procedure for net trans-carboboration. The method is modular as to the newly introduced carbon substituent (aryl, methyl, allyl, benzyl, alkynyl), which is invariably placed distal to the âOH group
Estimating Knots and Their Association in Parallel Bilinear Spline Growth Curve Models in the Framework of Individual Measurement Occasions
Latent growth curve models with spline functions are flexible and accessible
statistical tools for investigating nonlinear change patterns that exhibit
distinct phases of development in manifested variables. Among such models, the
bilinear spline growth model (BLSGM) is the most straightforward and intuitive
but useful. An existing study has demonstrated that the BLSGM allows the knot
(or change-point), at which two linear segments join together, to be an
additional growth factor other than the intercept and slopes so that
researchers can estimate the knot and its variability in the framework of
individual measurement occasions. However, developmental processes usually
unfold in a joint development where two or more outcomes and their change
patterns are correlated over time. As an extension of the existing BLSGM with
an unknown knot, this study considers a parallel BLSGM (PBLSGM) for
investigating multiple nonlinear growth processes and estimating the knot with
its variability of each process as well as the knot-knot association in the
framework of individual measurement occasions. We present the proposed model by
simulation studies and a real-world data analysis. Our simulation studies
demonstrate that the proposed PBLSGM generally estimate the parameters of
interest unbiasedly, precisely and exhibit appropriate confidence interval
coverage. An empirical example using longitudinal reading scores, mathematics
scores, and science scores shows that the model can estimate the knot with its
variance for each growth curve and the covariance between two knots. We also
provide the corresponding code for the proposed model.Comment: \c{opyright} 2020, American Psychological Association. This paper is
not the copy of record and may not exactly replicate the final, authoritative
version of the article. Please do not copy or cite without authors'
permission. The final article will be available, upon publication, via its
DOI: 10.1037/met000030
Chiral rings and GSO projection in Orbifolds
The GSO projection in the twisted sector of orbifold background is sometimes
subtle and incompatible descriptions are found in literatures. Here, from the
equivalence of partition functions in NSR and GS formalisms, we give a simple
rule of GSO projection for the chiral rings of string theory in \C^r/\Z_n,
. Necessary constructions of chiral rings are given by explicit mode
analysis.Comment: 24 page
Higher Criticism Statistic: Detecting and Identifying Non-Gaussianity in the WMAP First Year Data
Higher Criticism is a recently developed statistic for non-Gaussian
detection, proposed in Donoho & Jin 2004. We find that Higher Criticism is
useful for two purposes. First, Higher Criticism has competitive detection
power, and non-Gaussianity is detected at the level 99% in the first year WMAP
data. We find that the Higher Criticism value of WMAP is outside the 99%
confidence region at a wavelet scale of 5 degrees (99.46% of Higher Criticism
values based on simulated maps are below the values for WMAP). Second, Higher
Criticism offers a way to locate a small portion of data that accounts for the
non-Gaussianity. Using Higher Criticism, we have successfully identified a ring
of pixels centered at (l\approx 209 deg, b\approx -57 deg), which seems to
account for the observed detection of non-Gaussianity at the wavelet scale of 5
degrees. Note that the detection is achieved in wavelet space first. Second, it
is always possible that a fraction of pixels within the ring might deviate from
Gaussianity even if they do not appear to be above the 99% confidence level in
wavelet space. The location of the ring coincides with the cold spot detected
in Vielva et al. 2004 and Cruz et al. 2005.Comment: submitted to MNRA
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