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Markov Boundary Learning with Streaming Data for Supervised Classification

Chaofan Liu, Shuai Yang, Kui Yu
2020 IEEE Access  
KUI YU received the Ph.D. degree in computer science from the Hefei University of Technology, Hefei, China, in 2013.  ... 
doi:10.1109/access.2020.2998482 fatcat:3gnbu5i37fextiolallc3tndeu

Secure Collaborative Training and Inference for XGBoost [article]

Andrew Law, Chester Leung, Rishabh Poddar, Raluca Ada Popa, Chenyu Shi, Octavian Sima, Chaofan Yu, Xingmeng Zhang, Wenting Zheng
2020 arXiv   pre-print
In recent years, gradient boosted decision tree learning has proven to be an effective method of training robust models. Moreover, collaborative learning among multiple parties has the potential to greatly benefit all parties involved, but organizations have also encountered obstacles in sharing sensitive data due to business, regulatory, and liability concerns. We propose Secure XGBoost, a privacy-preserving system that enables multiparty training and inference of XGBoost models. Secure
more » ... protects the privacy of each party's data as well as the integrity of the computation with the help of hardware enclaves. Crucially, Secure XGBoost augments the security of the enclaves using novel data-oblivious algorithms that prevent access side-channel attacks on enclaves induced via access pattern leakage.
arXiv:2010.02524v1 fatcat:mh5gmhwqefe7lfh25jet2jgpzq

S3ML: A Secure Serving System for Machine Learning Inference [article]

Junming Ma, Chaofan Yu, Aihui Zhou, Bingzhe Wu, Xibin Wu, Xingyu Chen, Xiangqun Chen, Lei Wang, Donggang Cao
2020 arXiv   pre-print
We present S3ML, a secure serving system for machine learning inference in this paper. S3ML runs machine learning models in Intel SGX enclaves to protect users' privacy. S3ML designs a secure key management service to construct flexible privacy-preserving server clusters and proposes novel SGX-aware load balancing and scaling methods to satisfy users' Service-Level Objectives. We have implemented S3ML based on Kubernetes as a low-overhead, high-available, and scalable system. We demonstrate the
more » ... system performance and effectiveness of S3ML through extensive experiments on a series of widely-used models.
arXiv:2010.06212v1 fatcat:bb5krzimovfjtbdmvhxkb2snoa

Dynamic thermal coupling modeling and analysis of wet electro-hydrostatic actuator

Zongxia JIAO, Yanpeng LI, Tian YU, Chaofan JIANG, Ligang HUANG, Yaoxing SHANG
2021 Chinese Journal of Aeronautics  
The electro-hydrostatic actuator (EHA) used in more electric aircraft (MEA) has been extensively studied due to its advantages of high reliability and high integration. However, this high integration results in a small heat dissipation area, leading to high-temperature problems. Generally, to reduce the temperature, a wet cooling method of using the pump leakage oil to cool the motor is adopted, which can also increase the difficulty of accurately predicting the system temperature in the early
more » ... esign stage. To solve this problem, a dynamic coupling thermal model of a wet EHA is proposed in this paper. In particular, the leakage oil of the pump is used as a coupling item between the electrical system and the hydraulic system. Then, an improved T-equivalent block model is proposed to address the uneven distribution of axial oil temperature inside the motor, and the control node method is applied to hydraulic system thermal modeling. Meanwhile, a dynamic coupling thermal model is developed that enables a dynamic evaluation of the wet EHA temperature. Then, experimental prototypes of wet motor and wet EHA are developed, while the temperature response of the wet motor at different rotation speeds and different loads and the temperature response of the wet EHA at no-load condition were verified experimentally at room temperature, respectively. The maximum temperature difference between the experimental and theoretical results of the wet motor as well as the experimental and theoretical results of the wet EHA is less than 8°C. These test results indicate that the dynamic coupling thermal model is valid and demonstrate that the thermal coupling modeling method proposed in this paper can provide a basis for the detailed thermal design of EHA.
doi:10.1016/j.cja.2021.04.007 fatcat:fcnsqadb5vhajcmnr6aavuqinu

A Hybrid-Domain Framework for Secure Gradient Tree Boosting [article]

Wenjing Fang, Chaochao Chen, Jin Tan, Chaofan Yu, Yufei Lu, Li Wang, Lei Wang, Jun Zhou, Alex X
2020 arXiv   pre-print
Gradient tree boosting (e.g. XGB) is one of the most widely usedmachine learning models in practice. How to build a secure XGB inface of data isolation problem becomes a hot research topic. However, existing works tend to leak intermediate information and thusraise potential privacy risk. In this paper, we propose a novel framework for two parties to build secure XGB with vertically partitioneddata. Specifically, we associate Homomorphic Encryption (HE) domain with Secret Sharing (SS) domain by
more » ... providing the two-waytransformation primitives. The framework generally promotes theefficiency for privacy preserving machine learning and offers theflexibility to implement other machine learning models. Then weelaborate two secure XGB training algorithms as well as a corresponding prediction algorithm under the hybrid security domains.Next, we compare our proposed two training algorithms throughboth complexity analysis and experiments. Finally, we verify themodel performance on benchmark dataset and further apply ourwork to a real-world scenario.
arXiv:2005.08479v1 fatcat:2vbshbawhjhmxgyj4lhwooepdq

Near-Infrared Imaging for Information Embedding and Extraction with Layered Structures

Weiwei Jiang, Difeng Yu, Chaofan Wang, Zhanna Sarsenbayeva, Niels van Berkel, Jorge Goncalves, Vassilis Kostakos
2022 ACM Transactions on Graphics  
ACKNOWLEDGMENTS Weiwei Jiang, Difeng Yu and Chaofan Wang are supported by Melbourne Research Scholarships. Zhanna Sarsenbayeva is supported by a Doreen Thomas Postdoctoral Fellowship.  ... 
doi:10.1145/3533426 fatcat:5xjwtuu5zbc2rbwtbfaalcxjhq

Trajectory Generation and Optimization Using the Mutual Learning and Adaptive Ant Colony Algorithm in Uneven Environments

Feng Qu, Wentao Yu, Kui Xiao, Chaofan Liu, Weirong Liu
2022 Applied Sciences  
Aiming at the trajectory generation and optimization of mobile robots in complex and uneven environments, a hybrid scheme using mutual learning and adaptive ant colony optimization (MuL-ACO) is proposed in this paper. In order to describe the uneven environment with various obstacles, a 2D-H map is introduced in this paper. Then an adaptive ant colony algorithm based on simulated annealing (SA) is proposed to generate initial trajectories of mobile robots, where based on a de-temperature
more » ... n of the simulated annealing algorithm, the pheromone volatilization factor is adaptively adjusted to accelerate the convergence of the algorithm. Moreover, the length factor, height factor, and smooth factor are considered in the comprehensive heuristic function of ACO to adapt to uneven environments. Finally, a mutual learning algorithm is designed to further smooth and shorten initial trajectories, in which different trajectory node sequences learn from each other to acquire the shortest trajectory sequence to optimize the trajectory. In order to verify the effectiveness of the proposed scheme, MuL-ACO is compared with several well-known and novel algorithms in terms of running time, trajectory length, height, and smoothness. The experimental results show that MuL-ACO can generate a collision-free trajectory with a high comprehensive quality in uneven environments.
doi:10.3390/app12094629 fatcat:db2xuppmcfabfej6i7x7txkupm

Prognostic Value of Elevated Cardiac Troponin I After Aneurysmal Subarachnoid Hemorrhage

Fa Lin, Yu Chen, Qiheng He, Chaofan Zeng, Chaoqi Zhang, Xiaolin Chen, Yuanli Zhao, Shuo Wang, Jizong Zhao
2021 Frontiers in Neurology  
Object: Patients with aneurysmal subarachnoid hemorrhage (aSAH) have an increased incidence of cardiac events and short-term unfavorable neurological outcomes during the acute phase of bleeding. We studied whether troponin I elevation after ictus can predict future major adverse cardiac events (MACEs) and long-term neurological outcomes after 2 years.Methods: Consecutive aSAH patients within 3 days of bleeding were eligible for review from a prospective observational cohort (
more » ... dentifier: NCT04785976). Potential predictors of future MACEs and unfavorable long-term neurological outcomes were calculated by Cox and logistic regression analyses. Additional Kaplan–Meier curves were performed.Results: A total of 213 patients were enrolled with an average follow-up duration of 34.3 months. Individuals were divided into two groups: elevated cTnI group and unelevated cTnI group. By the last available follow-up, 20 patients had died, with an overall all-cause mortality rate of 9.4% and an annual all-cause mortality rate of 3.8%. Patients with elevated cTnI had a significantly higher risk of future MACEs (10.6 vs. 2.1%, p = 0.024, and 95% CI: 1.256–23.875) and unfavorable neurological outcomes at discharge, 3-month, 1-, 2-years, and last follow-up (p = 0.001, p < 0.001, p = 0.001, p < 0.001, and p < 0.001, respectively). In the Cox analysis for future MACE, elevated cTnI was the only independent predictor (HR = 5.980; 95% CI: 1.428–25.407, and p = 0.014). In the multivariable logistic analysis for unfavorable neurological outcomes, peak cTnI was significant (OR = 2.951; 95% CI: 1.376–6.323; p = 0.005). Kaplan–Meier analysis indicated that the elevated cTnI was correlated with future MACE (log-rank test, p = 0.007) and subsequent death (log-rank test, p = 0.004).Conclusion: cTnI elevation after aSAH could predict future MACEs and unfavorable neurological outcomes.
doi:10.3389/fneur.2021.677961 pmid:34135855 pmcid:PMC8200557 fatcat:57jeudq6jveoxmewmboeqzcqri

High Temperature Flexural Deformation Properties of Engineered Cementitious Composites (ECC) with Hybrid Fiber Reinforcement

Zhihui YU, Zhen YUAN, Chaofan XIA, Cong ZHANG
2020 Research and Application of Materials Science  
Author Contributions: Zhihui YU performed the experiment and wrote this manuscript; Zhen YUAN contributed significantly to manuscript preparation; Chaofan XIA performed the data analyses; Cong ZHANG helped  ... 
doi:10.33142/rams.v2i2.3168 fatcat:4msbpvzqc5gcbjekvhspx6aw3m

Taklimakan desert carbon-sink decreases under climate change

Fan Yang, Jianping Huang, Chenglong Zhou, Xinghua Yang, Mamtimin Ali, Chaofan Li, Honglin Pan, Wen Huo, Haipeng Yu, Xiaoyue Liu, Xinqian Zheng, Dongliang Han (+3 others)
2019 Science Bulletin  
The global carbon balance is a core issue in climate change research and a focus of international policy concern [1-3]. The "missing carbon sink" caused by approximately 1.6-2.0 Pg C a À1 (1 Pg = 10 15 g) that is currently unaccounted for, has long plagued researchers [4, 5] . Evidence is mounting those seemingly lifeless desert ecosystems, whose roles in the global carbon-cycle have long been neglected, exhibit the unconventional phenomenon of absorption of atmospheric CO 2 , sequestering
more » ... ous amounts of CO 2 and thereby creating a significant carbon-sink [6] [7] [8] [9] . This scenario appears to help narrow the gap in the missing carbonsink. However, this view has been questioned for the inaccurate carbon sequestration location [10] . The effects of abiotic processes, such as soil temperature gradient, moisture content, parent material, salt/alkali, and pH, on desert CO 2 exchange, have gradually revealed that the phenomenon of a desert carbon-sink is intimately associated with abiotic processes [11] . Thus far, the main processes, whereby, deserts act as carbon-sinks may include the following: (1) variation in the volume of gases caused by changes in pressure and temperature; (2) changes in solubility of CO 2 in soil water films; (3) pH-mediated CO 2 dissolution chemistry; and (4) surface adhesion of CO 2 onto soil minerals [11] [12] [13] . In ecosystems with relatively high productivity, the effects of abiotic processes on CO 2 exchange are often neglected because of strong biological respiration. In desert ecosystems, however, the effects of abiotic processes on CO 2 exchange cannot be ignored, although the CO 2 flux is extremely weak. The effects of abiotic processes are even greater than the effects of biological processes [11, 14] . The latest research indicates that the absorbed CO 2 gradually, enters the desert groundwater layer by the process of leaching, and eventually converge in the underground saline water layer under the vast desert with the groundwater movement. This process is similar to the inorganic carbon sinks in the ocean [9] . The Taklimakan Desert (TD) is the world's second-largest shifting desert and plays a vital role in the carbon-sink properties of desert ecosystems. Benefit by the abundant saline-alkali groundwater and extensive salinization, the TD has a huge carbon storage capacity. However, there is uncertainty regarding the magnitude of the contribution made by each internal process towards the TD carbon-sink; and how these processes will respond to climate change. The TD land surface mainly consists of continuous shifting sand cover, which shows the high homogeneity of this desert. Therefore, the hinterland of the TD can be considered the most representative research area in this desert. In the hinterland of the TD, through a combination of partitioning (dealkalization/desalination, sterilization, and drying) and temperature-controlled experiments, we found that the contribution of various shifting sand components to the total CO 2 flux in the shifting sand is strongly linked to soil temperature. The soil temperature difference between depths of 0 and 10 cm and the rate of soil temperature change at a depth of 10 cm are the two main factors driving CO 2 exchange in the shifting sand. Besides, we obtained the contribution of the CO 2 fluxes of various components in the TD shifting sand (Fig. 1a) . Comparing demonstrate that the expansion/contraction of soil air containing CO 2 caused by heat fluctuation in shifting sand provides an unexpectedly strong contribution towards total CO 2 exchange. This long-hidden process in combination with salts/alkali
doi:10.1016/j.scib.2019.12.022 fatcat:x67dztlxufdwfp3nudxkp2bldq

Long-Term Assessment of Rehabilitation Treatment of Sports through Artificial Intelligence Research

Chaofan Zeng, Ying Huang, Longer Yu, Qingmei Zeng, Bijun Wang, Yi Xu, Kelvin Wong
2021 Computational and Mathematical Methods in Medicine  
Background. Artificial intelligence (AI) technology has been incorporated into all walks of life, especially the integration of machine learning and health management has achieved very significant progress and results. It is very necessary to analyze personalized sports health management services and long-term assessment of health issues in the era of AI. Methods. This paper explores AI + personalized sports management service system design ideas, system operation process, management stage
more » ... n, taking common chronic diseases, and diabetes as examples. 150 patients were divided into an observation group and a control group, and the blood glucose, blood pressure, blood lipid, and knowledge awareness rate were compared. Results. The blood glucose, blood pressure, and blood lipid levels of the observation group all reduced, and the awareness rate of diabetes knowledge increased, which proved that the AI research has great value in sports rehabilitation research coupled with long term health assessment and is worth further research. Conclusion. The AI research proposed in this paper is of far-reaching practical significance in helping the transformation and upgrading of the sports health management service industry, promoting the innovative development of sports health management service supply, and promoting national fitness and national health.
doi:10.1155/2021/4980718 pmid:34976108 pmcid:PMC8716213 fatcat:bxeislomsngsdoujhmtqzoztgi

Amiloride Enhances Antigen Specific CTL by Faciliting HBV DNA Vaccine Entry into Cells

Shuang Geng, Yiwei Zhong, Shuang Wang, Hu Liu, Qiang Zou, Xiaoping Xie, Chaofan Li, Qingling Yu, Zhonghuai He, Bin Wang, Roberto F. Speck
2012 PLoS ONE  
The induction of relatively weak immunity by DNA vaccines in humans can be largely attributed to the low efficiency of transduction of somatic cells. Although formulation with liposomes has been shown to enhance DNA transduction of cultured cells, little, if any, effect is observed on the transduction of somatic tissues and cells. To improve the rate of transduction, DNA vaccine delivery by gene gun and the recently developed electroporation techniques have been employed. We report here that to
more » ... circumvent requirement for such equipment, amiloride, a drug that is prescribed for hypertension treatment, can accelerate plasmid entry into antigen presenting cells (APCs) both in vitro and in vivo. The combination induced APCs more dramatically in both maturation and cytokine secretion. Amiloride enhanced development of full CD8 cytolytic function including induction of high levels of antigen specific CTL and expression of IFN-c+perforin+granzymeB+ in CD8+ T cells. Thus, amiloride is a facilitator for DNA transduction into host cells which in turn enhances the efficiency of the immune responses.
doi:10.1371/journal.pone.0033015 pmid:22438887 pmcid:PMC3306379 fatcat:eme44i3w4jcwll6ckljw2uvnfe

Effects of Cropland Conversion and Climate Change on Agrosystem Carbon Balance of China's Dryland: A Typical Watershed Study

Chaofan Li, Qifei Han, Geping Luo, Chengyi Zhao, Shoubo Li, Yuangang Wang, Dongsheng Yu
2018 Sustainability  
the Knowledge Innovation Program of Institute of Soil Science, Chinese Academy of Sciences grant number ISSASIP1630; and the Startup Foundation for Introducing Talent of NUIST grant number 2017r036 to Chaofan  ... 
doi:10.3390/su10124508 fatcat:ulqxyqcgxfeabl7hdl2wy5jqhe

Reactivation of Denervated Schwann Cells by Embryonic Spinal Cord Neurons to Promote Axon Regeneration and Remyelination

Xinyu Fang, Chaofan Zhang, Chongjing Zhang, Yuanqing Cai, Zibo Yu, Zida Huang, Wenbo Li, Wenming Zhang
2019 Stem Cells International  
In peripheral nerve injuries (PNIs) in which proximal axons do not regenerate quickly enough, significant chronic degeneration of Schwann cells (SCs) can occur at the distal stump of the injured nerve and obstruct regeneration. Cell transplantation can delay the degeneration of SCs, but transplanted cells fail to generate voluntary electrical impulses without downstream signal stimulation from the central nervous system. In this study, we combined cell transplantation and nerve transfer
more » ... es to investigate whether the transplantation of embryonic spinal cord cells could benefit the microenvironment of the distal stump of the injured nerve. The experiment consisted of two stages. In the first-stage surgery, common peroneal nerves were transected, and embryonic day 14 (E14) cells or cell culture medium was transplanted into the distal stump of the CPs. Six months after the first-stage surgery, the transplanted cells were removed, and the nerve segment distal to the transplanted site was used to bridge freshly cut tibial nerves to detect whether the cell-treated graft promoted axon growth. The phenotypic changes and the neurotrophic factor expression pattern of SCs distal to the transplanted site were detected at several time points after cell transplantation and excision. The results showed that at different times after transplantation, the cells could survive and generate neurons. Thus, the neurons play the role of proximal axons to prevent chronic degeneration and fibrosis of SCs. After excision of the transplanted cells, the SCs returned to their dedifferentiated phenotype and upregulated growth-associated gene expression. The ability of SCs to be activated again allowed a favorable microenvironment to be created and enhanced the regeneration and remyelination of proximal axons. Muscle reinnervation was also elevated. This transplantation strategy could provide a treatment option for complex neurological injuries in the clinic.
doi:10.1155/2019/7378594 pmid:31885623 pmcid:PMC6915008 fatcat:oposrdkoffgorizeg6dvwpihvq

Ultrasensitive monitoring of DNA damage associated with free radicals exposure using dynamic carbon nanotubes bridged interdigitated electrode array

Hui Zhao, Misha Liu, Tao Jiang, Jinjin Xu, Huirong Zhang, Chaofan Yu, Zipeng Liu, Ying Wang, Longhua Tang
2020 Environment International  
Chaofan Yu: Validation, Writing -review & editing. Zipeng Liu: Resources, Visualization. Ying Wang: Supervision, Funding acquisition, Conceptualization.  ... 
doi:10.1016/j.envint.2020.105672 pmid:32248022 fatcat:fd2m2exp6bfc5l7w7arefcucna
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