306 research outputs found
The PD-Utility Function for Prospect Behavior and Related Researches
Based on Partial Distribution [11],[12], we put forward a PD-utility function of prospect behavior for the first time, the profiting utility function and losing utility function. The PD-utility function can reflect sufficiently the human¡¯s risk preferences properties to profiting or losing, describe and bring to light availably the important relations between profiting utility and losing utility, and interpret many conclusions in Daniel Kahneman¡¯s prospect theory in analytic way. Also we present the concepts and analytic expressions of essential indexes of realized level for prospect behavior, the limit value, the balanced value, and focus value, especially the method of calculating them. The limit level is beneficial to judge the reversal position of reality movement trend, and the latter is beneficial to judge that the focus of current reality is reasonableness or not. And we give out the calculating formula for the optimal value of realized level for prospect with its appearing probability.partial distribution, PD-utility function, prospect behavior, essential indexes, optimal value
Vehicular Fog Computing Enabled Real-time Collision Warning via Trajectory Calibration
Vehicular fog computing (VFC) has been envisioned as a promising paradigm for
enabling a variety of emerging intelligent transportation systems (ITS).
However, due to inevitable as well as non-negligible issues in wireless
communication, including transmission latency and packet loss, it is still
challenging in implementing safety-critical applications, such as real-time
collision warning in vehicular networks. In this paper, we present a vehicular
fog computing architecture, aiming at supporting effective and real-time
collision warning by offloading computation and communication overheads to
distributed fog nodes. With the system architecture, we further propose a
trajectory calibration based collision warning (TCCW) algorithm along with
tailored communication protocols. Specifically, an application-layer
vehicular-to-infrastructure (V2I) communication delay is fitted by the Stable
distribution with real-world field testing data. Then, a packet loss detection
mechanism is designed. Finally, TCCW calibrates real-time vehicle trajectories
based on received vehicle status including GPS coordinates, velocity,
acceleration, heading direction, as well as the estimation of communication
delay and the detection of packet loss. For performance evaluation, we build
the simulation model and implement conventional solutions including cloud-based
warning and fog-based warning without calibration for comparison. Real-vehicle
trajectories are extracted as the input, and the simulation results demonstrate
that the effectiveness of TCCW in terms of the highest precision and recall in
a wide range of scenarios
Frequency Compensated Diffusion Model for Real-scene Dehazing
Due to distribution shift, deep learning based methods for image dehazing
suffer from performance degradation when applied to real-world hazy images. In
this paper, we consider a dehazing framework based on conditional diffusion
models for improved generalization to real haze. First, we find that optimizing
the training objective of diffusion models, i.e., Gaussian noise vectors, is
non-trivial. The spectral bias of deep networks hinders the higher frequency
modes in Gaussian vectors from being learned and hence impairs the
reconstruction of image details. To tackle this issue, we design a network
unit, named Frequency Compensation block (FCB), with a bank of filters that
jointly emphasize the mid-to-high frequencies of an input signal. We
demonstrate that diffusion models with FCB achieve significant gains in both
perceptual and distortion metrics. Second, to further boost the generalization
performance, we propose a novel data synthesis pipeline, HazeAug, to augment
haze in terms of degree and diversity. Within the framework, a solid baseline
for blind dehazing is set up where models are trained on synthetic hazy-clean
pairs, and directly generalize to real data. Extensive evaluations show that
the proposed dehazing diffusion model significantly outperforms
state-of-the-art methods on real-world images.Comment: 16 page
Key issues and development direction of petroleum geology research of source rock strata in China
After more than 20 years of technological advancements, the novel field of oil and gas production from source rock strata, which comprise tight and shale oil and gas reservoirs, has become the major contributor to the increase in unconventional oil and gas reserves in China. Accordingly, this field has gradually entered a new stage of revolutionary development. The oil and gas production in China from source rock strata will achieve sustainable development in the future. Different types of source rock strata present distinct challenges and require diverse development paths. Based on the geological conditions of source rock strata in China, this study focuses on identifying the “sweet areas” among hydrocarbon accumulations. It specifically analyzes the key development issues of tight oil, tight gas, shale oil, shale gas, and coal-bed methane, while proposing potential solutions and identifying the possible directions for future development. This study aims to provide a reference for scientists concerned with the development of unconventional oil and gas reserves in China.Cited as: Li, J., Yang, Z., Wu, S., Pan, S. Key issues and development direction of petroleum geology research on source rock strata in China. Advances in Geo-Energy Research, 2021, 5(2): 121-126, doi: 10.46690/ager.2021.02.0
Characterization of mineral and pore evolution under CO2-brine-rock interaction at in-situ conditions
Herein, a method of physical modeling of CO2-brine-rock interaction and in-situ characterization of mineral and pore evolution is established. The nested preparation and installation of the same sample with different sizes could protect and keep the integrality of the millimeter-size sample in conventional high-temperature and high-pressure reactors. This paper establishes a procedure to obtain the three-dimensional in-situ comparison of minerals and pores before and after the reaction. The resolution is updated from 5-10 µ m to 10 nm, which could be helpful for modeling CO2-brine-rock interaction in unconventional tight reservoirs. This method could be applied to CO2-enhanced oil recovery as well as CO2 capture, utilization, and storage scientific research. Furthermore, it may shed light on the carbon sequestration schemes in the Chinese petroleum industry.Cited as: Wu, S., Yu, C., Hu, X., Yu, Z., Jiang, X. Characterization of mineral and pore evolution under CO2-brine-rock interaction at in-situ conditions. Advances in Geo-Energy Research, 2022, 6(2): 177-178. https://doi.org/10.46690/ager.2022.02.0
Basic properties and exploitation strategies of source rock strata
Source rock strata are filled and aggregated with large-scale continuous hydrocarbon resources, including significant volumes of in-place retained, short-distance migrated and potentially generated hydrocarbons. Source rock strata simultaneously possess the properties of reservoirs and hydrocarbon source rocks, known as source-reservoir coexisting systems. Reservoir properties refer to the physical properties concerning the storage and transmission of oil and gas, while hydrocarbon source rock properties refer to the physicochemical properties related to governing the generation, retention and expulsion of oil and gas in the source rock strata. These properties fundamentally determine the technical path for the successful exploitation of petroleum and natural gas in the source rock strata. With regard to reservoir properties, in-depth research and development of the advanced energy-storing fracturing technology can aid the construction of complex fracture networks to overcome the limitations in the connectivity properties of source rock strata. Focusing on the hydrocarbon source rock properties, an underground in-situ conversion technology should be created and developed to alleviate the shortcomings of organic matter quantity and maturity properties of the source rock strata. Furthermore, selecting the appropriate exploitation path based on the property characteristics can promote the achievement of commercial and sustainable development of oil and gas in the source rock strata.Document Type: PerspectiveCited as: Yang, Z., Zou, C., Fan, Y., Wu, S., Liu, H., Wei, Q. Basic properties and exploitation strategies of source rock strata. Advances in Geo-Energy Research, 2023, 10(2): 77-83. https://doi.org/10.46690/ager.2023.11.0
Speech-Driven 3D Face Animation with Composite and Regional Facial Movements
Speech-driven 3D face animation poses significant challenges due to the
intricacy and variability inherent in human facial movements. This paper
emphasizes the importance of considering both the composite and regional
natures of facial movements in speech-driven 3D face animation. The composite
nature pertains to how speech-independent factors globally modulate
speech-driven facial movements along the temporal dimension. Meanwhile, the
regional nature alludes to the notion that facial movements are not globally
correlated but are actuated by local musculature along the spatial dimension.
It is thus indispensable to incorporate both natures for engendering vivid
animation. To address the composite nature, we introduce an adaptive modulation
module that employs arbitrary facial movements to dynamically adjust
speech-driven facial movements across frames on a global scale. To accommodate
the regional nature, our approach ensures that each constituent of the facial
features for every frame focuses on the local spatial movements of 3D faces.
Moreover, we present a non-autoregressive backbone for translating audio to 3D
facial movements, which maintains high-frequency nuances of facial movements
and facilitates efficient inference. Comprehensive experiments and user studies
demonstrate that our method surpasses contemporary state-of-the-art approaches
both qualitatively and quantitatively.Comment: Accepted by MM 2023, 9 pages, 7 figures. arXiv admin note: text
overlap with arXiv:2303.0979
Federated Learning over a Wireless Network: Distributed User Selection through Random Access
User selection has become crucial for decreasing the communication costs of
federated learning (FL) over wireless networks. However, centralized user
selection causes additional system complexity. This study proposes a network
intrinsic approach of distributed user selection that leverages the radio
resource competition mechanism in random access. Taking the carrier sensing
multiple access (CSMA) mechanism as an example of random access, we manipulate
the contention window (CW) size to prioritize certain users for obtaining radio
resources in each round of training. Training data bias is used as a target
scenario for FL with user selection. Prioritization is based on the distance
between the newly trained local model and the global model of the previous
round. To avoid excessive contribution by certain users, a counting mechanism
is used to ensure fairness. Simulations with various datasets demonstrate that
this method can rapidly achieve convergence similar to that of the centralized
user selection approach
Paleoenvironment and chemostratigraphy heterogenity of the Cretaceous organic-rich shales
The Cretaceous Qingshankou Formation in the Songliao Basin is rich in shale oil resources, which has become one of the most important exploration targets of lacustrine shale oil in China. Based on X-ray fluorescence element analysis, X-ray diffraction analysis, total organic carbon, rock pyrolysis, scanning electron microscope and nitrogen adsorption, the Paleoenvironment was reconstructed by comprehensive utilization of integrated prediction error filter analysis of chemical stratigraphy, and its relationship with organic geochemistry, mineralogy and pore structure was discussed. The results indicated that the Qingshankou Formation was deposited in the environment with fresh water-brackish water, semi-deep/deep water and strong reduction. The evolution of Paleoenvironment during the deposition of Qingshankou Formation changed from bottom to top, with increasing water depth, decreasing salinity and oxygen content. Paleosalinity was positively correlated with total organic carbon, residual hydrocarbon and carbonate mineral content. From bottom to top, the contents of carbonate and chlorite decreased, while the contents of plagioclase and clay minerals increased slightly. The pores were dominated by intra-illite pores, intra-I/S mixed-layer pores and intra-pyrite pores. Some intra-plagioclase pores and calcite dissolution pores were developed, and the organic matter pores are slightly few. Nitrogen adsorption data showed that the dominate pore size was 40-53 nm. This study clarifies the Paleoenvironmental evolution of the Qingshankou Formation, and may shed lights on lacustrine shale oil accumulation and sweet-spotting.Cited as: Guan, M., Wu, S., Hou, L., Jiang, X., Ba, D., Hua, G. Paleoenvironment and chemostratigraphy heterogenity of the Cretaceous organic-rich shales. Advances in Geo-Energy Research, 2021, 5(4): 444-455, doi: 10.46690/ager.2021.04.0
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