309 research outputs found
Zero-Shot Recognition using Dual Visual-Semantic Mapping Paths
Zero-shot recognition aims to accurately recognize objects of unseen classes
by using a shared visual-semantic mapping between the image feature space and
the semantic embedding space. This mapping is learned on training data of seen
classes and is expected to have transfer ability to unseen classes. In this
paper, we tackle this problem by exploiting the intrinsic relationship between
the semantic space manifold and the transfer ability of visual-semantic
mapping. We formalize their connection and cast zero-shot recognition as a
joint optimization problem. Motivated by this, we propose a novel framework for
zero-shot recognition, which contains dual visual-semantic mapping paths. Our
analysis shows this framework can not only apply prior semantic knowledge to
infer underlying semantic manifold in the image feature space, but also
generate optimized semantic embedding space, which can enhance the transfer
ability of the visual-semantic mapping to unseen classes. The proposed method
is evaluated for zero-shot recognition on four benchmark datasets, achieving
outstanding results.Comment: Accepted as a full paper in IEEE Computer Vision and Pattern
Recognition (CVPR) 201
Structural design using a parallel sequential approximate optimization
In this paper, a parallel sampling strategy dedicated to SAO is proposed to enhance
the competence of exploration and convergence simultaneously in the optimization process. In
the parallel sampling procedure, new sampling points are identified in the pareto front of the
multi-objective optimization problem, which is solved with the Normal constraint (NC) method.
The objectives of the optimization problem are the two indices to represent the competence of
exploration and convergence, and the sampled points will be evaluated by the true model in a
parallel way. Furthermore, the proposed methodology is evaluated on two benchmark tests.
Compared to other optimization algorithms, the PSAO algorithm yields equivalent or better
objective values while the number of optimization iterations required to find the same global
optima is reduced by multiple orders of magnitude, which substantially reduce the computing
costs in the tested structural design optimization tasks, highlighting the applicability of the
PSAO structural design optimization problems
Effects of Shading on Carbohydrates of Syzygium samarangense
Wax apple (Syzygium samarangense) is an important tropical fruit tree cultivated in Southeast Asian. It produces red pear-like shape fruits. The fruit flesh is considered high in antioxidants, phenolics, and flavonoids that have a potential to contribute to the human healthy diet, and was proved to have anti-inflammatory and antimicrobial characteristics. To allow year-round marketing of high quality wax apple fruit, growers always perform shading to inhibit new flushes so as to repress vegetative growth and promote reproductive growth. To investigate the effect of shading on carbohydrates, wax apple trees were shaded with sun shade nets under field conditions. The effects of shading on shoot growth were studied and leaf carbohydrate levels of the trees were determined. The results showed that shading inhibit the the growth of the terminal shoots and promoted bud dormancy. Shading also reduced total soluble sugar, sucrose, glucose, fructose, and starch levels of leaves. The results suggested that shading reduced carbohydrate accumulation and repressed vegetative growth
Coverage Dependent H Desorption Energy: a Quantitative Explanation Based on Encounter Desorption Mechanism
Recent experiments show that the desorption energy of H on a diamond-like
carbon (DLC) surface depends on the H coverage of the surface. We aim to
quantitatively explain the coverage dependent H desorption energy measured
by the experiments. We derive a math formula to calculate an effective H
desorption energy based on the encounter desorption mechanism. The effective
H desorption energy depends on two key parameters, the desorption energy of
H on H substrate and the ratio of H diffusion barrier to its
desorption energy. The calculated effective H desorption energy
qualitatively agrees with the coverage dependent H desorption energy
measured by the experiments if the values of these two parameters in literature
are used in the calculations. We argue that the difference between the
effective H desorption energy and the experimental results is due to the
lacking of knowledge about these two parameters. So, we recalculate these two
parameters based on experimental data. Good agreement between theoretical and
experimental results can be achieved if these two updated parameters are used
in the calculations.Comment: 6 pages,6 figures,2 tables, accepted for publication in MNRA
Adaptive Steganalysis Based on Selection Region and Combined Convolutional Neural Networks
Digital image steganalysis is the art of detecting the presence of information hiding in carrier images. When detecting recently developed adaptive image steganography methods, state-of-art steganalysis methods cannot achieve satisfactory detection accuracy, because the adaptive steganography methods can adaptively embed information into regions with rich textures via the guidance of distortion function and thus make the effective steganalysis features hard to be extracted. Inspired by the promising success which convolutional neural network (CNN) has achieved in the fields of digital image analysis, increasing researchers are devoted to designing CNN based steganalysis methods. But as for detecting adaptive steganography methods, the results achieved by CNN based methods are still far from expected. In this paper, we propose a hybrid approach by designing a region selection method and a new CNN framework. In order to make the CNN focus on the regions with complex textures, we design a region selection method by finding a region with the maximal sum of the embedding probabilities. To evolve more diverse and effective steganalysis features, we design a new CNN framework consisting of three separate subnets with independent structure and configuration parameters and then merge and split the three subnets repeatedly. Experimental results indicate that our approach can lead to performance improvement in detecting adaptive steganography
Lineage tracing for multiple lung cancer by spatiotemporal heterogeneity using a multi-omics analysis method integrating genomic, transcriptomic, and immune-related features
IntroductionThe distinction between multiple primary lung cancer (MPLC) and intrapulmonary metastasis (IPM) holds clinical significance in staging, therapeutic intervention, and prognosis assessment for multiple lung cancer. Lineage tracing by clinicopathologic features alone remains a clinical challenge; thus, we aimed to develop a multi-omics analysis method delineating spatiotemporal heterogeneity based on tumor genomic profiling.MethodsBetween 2012 and 2022, 11 specimens were collected from two patients diagnosed with multiple lung cancer (LU1 and LU2) with synchronous/metachronous tumors. A novel multi-omics analysis method based on whole-exome sequencing, transcriptome sequencing (RNA-Seq), and tumor neoantigen prediction was developed to define the lineage. Traditional clinicopathologic reviews and an imaging-based algorithm were performed to verify the results.ResultsSeven tissue biopsies were collected from LU1. The multi-omics analysis method demonstrated that three synchronous tumors observed in 2018 (LU1B/C/D) had strong molecular heterogeneity, various RNA expression and immune microenvironment characteristics, and unique neoantigens. These results suggested that LU1B, LU1C, and LU1D were MPLC, consistent with traditional lineage tracing approaches. The high mutational landscape similarity score (75.1%), similar RNA expression features, and considerable shared neoantigens (n = 241) revealed the IPM relationship between LU1F and LU1G which were two samples detected simultaneously in 2021. Although the multi-omics analysis method aligned with the imaging-based algorithm, pathology and clinicopathologic approaches suggested MPLC owing to different histological types of LU1F/G. Moreover, controversial lineage or misclassification of LU2’s synchronous/metachronous samples (LU2B/D and LU2C/E) traced by traditional approaches might be corrected by the multi-omics analysis method. Spatiotemporal heterogeneity profiled by the multi-omics analysis method suggested that LU2D possibly had the same lineage as LU2B (similarity score, 12.9%; shared neoantigens, n = 71); gefitinib treatment and EGFR, TP53, and RB1 mutations suggested the possibility that LU2E might result from histology transformation of LU2C despite the lack of LU2C biopsy and its histology. By contrast, histological interpretation was indeterminate for LU2D, and LU2E was defined as a primary or progression lesion of LU2C by histological, clinicopathologic, or imaging-based approaches.ConclusionThis novel multi-omics analysis method improves the accuracy of lineage tracing by tracking the spatiotemporal heterogeneity of serial samples. Further validation is required for its clinical application in accurate diagnosis, disease management, and improving prognosis
The seeds of ecological recovery in urbanization-Spatiotemporal evolution of ecological resiliency of Dianchi Lake Basin, China
As a result of years of monitoring the ecological resiliency of natural areas and cities, it has become clear that it is both important and often feasible to implement ecological and environmental restoration in conjunction with ongoing processes of landscape change development and urbanization. Ecological resiliency and spatiotemporal evolution studies can objectively reveal the resiliency of ecosystems to external disturbances. Ecological monitoring and assessment can also help planners understand regional ecological spatial differentiation patterns and provided data support for planning. In this paper we have analyzes quantitatively the interrelationships of ecological factors in Dianchi Lake Basin (DLB) over the past 30 years and explored the spatial and temporal dynamics of ecological resiliency. Based on remote sensing images and primary data in 1995, 2005, 2010, 2015, 2018, and 2022, we used the center of gravity migration and kernel density analysis to explore the spatial and temporal changes of ecological resiliency. We built the overall resiliency evaluation system using entropy weight in the TOPSIS model, and finally simulate the future changes based on CA-Markov (CA-MC) model. The results show that from 1995 to 2022, the ecological resiliency of land use and vegetation cover in DLB decreased substantially. An important finding was that the ecological resiliency of riparian buffer zone and landscape pattern were generally increasing. The distribution of barycenter movement and kernel density of different levels of ecological resiliency differed significantly and showed fluctuating changes. The extreme low resiliency and extremely resilient areas shift to the northeast, the mildly resilient areas shift to the northwest, and the highly resilient areas shift to the southeast. The overall resiliency level of DLB is predicted to slowly increase from 2022 to 2030 by deduction of the CA-MC model. Our analysis suggests that the study of the evolution of regional ecological resiliency can provide a timely understanding of regional ecological evolution patterns and propose ecological protection strategies
Topological Electronic Structure Evolution with Symmetry Breaking Spin Reorientation in (FeCo)Sn
Topological materials hosting kagome lattices have drawn considerable
attention due to the interplay between topology, magnetism, and electronic
correlations. The (FeCo)Sn system not only hosts a kagome lattice
but has a tunable symmetry breaking magnetic moment with temperature and
doping. In this study, angle resolved photoemission spectroscopy and first
principles calculations are used to investigate the interplay between the
topological electronic structure and varying magnetic moment from the planar to
axial antiferromagnetic phases. A theoretically predicted gap at the Dirac
point is revealed in the low temperature axial phase but no gap opening is
observed across a temperature dependent magnetic phase transition. However,
topological surface bands are observed to shift in energy as the surface
magnetic moment is reduced or becomes disordered over time during experimental
measurements. The shifting surface bands may preclude the determination of a
temperature dependent bulk gap but highlights the intricate connections between
magnetism and topology with a surface/bulk dichotomy that can affect material
properties and their interrogation.Comment: 11 pages, 4 figure
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