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Differentially private SGD with random features

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 1-23页

作者： WANG Yi-guang guo Zheng-chu Polytechnic Institute of Zhejiang University Zhejiang UniversityHangzhou 310015China School of Mathematical Sciences Zhejiang UniversityHangzhou 310058China

In the realm of large-scale machine learning,it is crucial to explore methods for reducing computational complexity and memory demands while maintaining generalization ***,since the collected data may contain some sensitive information,it is also of great significance to study privacy-preserving machine learning *** paper focuses on the performance of the differentially private stochastic gradient descent(SGD)algorithm based on random *** begin,the algorithm maps the original data into a lowdimensional space,thereby avoiding the traditional kernel method for large-scale data storage ***,the algorithm iteratively optimizes parameters using the stochastic gradient descent ***,the output perturbation mechanism is employed to introduce random noise,ensuring algorithmic *** prove that the proposed algorithm satisfies the differential privacy while achieving fast convergence rates under some mild conditions.

关键词： learning theory differential privacy stochastic gradient descent random features reproducing kernel Hilbert spaces

Energy Consumption in Comminution of Mica with Cavitation Abrasive Water Jet

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Journal of China University of Mining and Technology 2007年第2期17卷 251-254页

作者： guo chu-wen DONG Lu College of Mechanical ＆ Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

We have studied the efficiency of energy consumption in the comminution of mica powder with cavitation abrasive water jet technology. The energy required to create new surfaces in the comminution of mica powder with cavitation abrasive water jet was calculated,in order to estimate its efficiency of energy consumption. The particle size distribution and the specific surface area were measured by applying a JEM-200CX transmission electron microscope and an Autosorb-1 automatic surface area analyzer. The study results show that the efficiency of energy consumed in creating new surface areas is as high as 2.92%,or 4.94% with the aid of cavitation in the comminution of mica powder. This efficiency will decrease with an increase in the number of comminutions. After three comminutions,the efficien-cies will become 1.91% and 2.29% for comminution without cavitation and with cavitation,respectively. The abrasive water jet technology is an effective way for comminution of mica powder.

关键词： energy consumption comminution mica cavitation abrasive water jet

Performance improvement for applying network virtualization in fiber-wireless(FiWi) access networks

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第11期15卷 1058-1070页

作者： Qing-long DAI guo-chu SHOU Yi-hong HU Zhi-gang guo Beijing Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications

Fiber-wireless(FiWi) access networks, which are a combination of fiber networks and wireless networks,have the advantages of both networks, such as high bandwidth, high security, low cost, and flexible access. However,with the increasing need for bandwidth and types of service from users, FiWi networks are still relatively incapable and ossified. To alleviate bandwidth tension and facilitate new service deployment, we attempt to apply network virtualization in FiWi networks, in which the network's control plane and data plane are separated from each *** on a previously proposed hierarchical model and service model for FiWi network virtualization, the process of service implementation is described. The performances of the FiWi access networks applying network virtualization are analyzed in detail, including bandwidth for links, throughput for nodes, and multipath flow *** results show that the FiWi network with virtualization is superior to that without.

关键词： FiWi access networks Network virtulization Performance analysis

Research on Noise Control for Ventilators with Resonance

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Journal of China University of Mining and Technology 2006年第1期16卷 25-27页

作者： guo chu-wen SUN Fei-hong College of Mechanical and Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Xuzhou Institute of Architectural Technology Xuzhou Jiangsu 221008 China

A study was carried out to control the noise produced by the ventilators at the Luling coalmine, which had caused serious noise pollution to the residents living around the mine for a long time. The main noise source was found to be the dynamic noise at the outlet of the diffuser. The frequency of its peak value was 250 Hz. A special brick with a resonant frequency of 250 Hz was designed to eliminate this noise. The diffusion of a lower frequency noise has been successfully controlled by the installation of a noise-eliminating tower above the diffuser outlet. The detection results show that the noise in the nearby residential area has been lowered to an average 55.3dB(A) in the daytime from 69.8dB(A) and to 48.4dB(A) at night from 65.8dB(A).

关键词： Resonance noise ventilator noise control coalmine

Surface tuning of LaCoO_(3) perovskite by acid etching to enhance its catalytic performance

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Rare Metals 2021年第3期40卷 555-562页

作者： Lu Dai Xin-Bo Lu guo-Hai chu Cheng-Huan He Wang-Cheng Zhan guo-Jun Zhou China Tobacco Zhejiang Industrial Co. LtdHangzhou 310024China Research Institute Catalysis School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

The stoichiometric LaCoO_(3) and nonstoichiometric LaCo_(1.2)O_(3) perovskite catalysts were prepared by citric acid sol-gel method,and then,LaCoO_(3) perovskite was etched with nitric *** structure,surface composition and reducibility of the catalyst were studied by X-ray diffraction(XRD),nitrogen desorption,transmission electron microscope(TEM),temperature program reduction of H_(2)(H_(2)-TPR) and X-ray photoelectron spectroscopy(XPS).It was found that nitric acid etching did not change the crystal structure and the overall morphology of the LaCoO_(3) catalyst,but it can cause the exposure of B-site Co metal to the surface of the *** a result,after acid etching,the reducibility of the LaCoO_(3) catalyst was improved,leading to the improvement in the catalytic activity of the LaCoO_(3) catalyst for CO oxidation and C_(3)H_(8) ***,the catalytic activity of the LaCoO_(3) catalyst after acid etching was higher than that of LaCo_(1.2)O_(3) and CoOx/LaCoO_(3) catalyst.

关键词： Perovskite oxide Acid etching CO oxidation Propane combustion

Efficient Chemical Synthesis and Folding of Mirror-Image Tropomyosin Receptor Kinase A Using the Strategy of Removable Glycosylation Modification

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Chinese Journal of Chemistry 2024年第19期42卷 2316-2322页

作者： Tongyue Wang Weiwei Shi guo-Chao chu Yi-Ming Li Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology Department of ChemistryTsinghua UniversityBeijing 100084China School of Food and Biological Engineering Engineering Research Center of Bio-processMinistry of EducationKey Laboratory of Animal Source of Anhui ProvinceHefei University of TechnologyHefeiAnhui 230009China

Comprehensive Summary The strategy of removable glycosylation modification was used to overcome the low-efficiency problem encountered in the chemical synthesis of the mirror-image D-version of the immunoglobulin(Ig)-like domain of tropomyosin receptor kinase A(DlgCTrkA),a protein molecule needed for mirror-image screening of D-peptide ligands targeting this cell membrane *** was found that O-linked-β-N-acetyl-D-glucosamine(O-GlcNAc)modification at^(D)Ser^(312),or^(D)Ser^(320)can significantly improve the efficiency of DlgCTrkA synthesis and folding,while O-GlcNAc modification at^(D)Ser^(330)showed barely any *** study provides a new example demonstrating the power of the removable glycosylation modification strategy in the chemical synthesis and folding of difficult-to-obtain *** also presents evidence that removable glycosylation modification at different sites would significantly affect the efficiency of protein folding promoted by this strategy.

关键词： Chemical protein synthesis Removable glycosylation modification Synthetic methods Protein folding D-protein

Clinopyroxene and Fe-Ti oxides for correlating the ash from Changbaishan Millennium eruption

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Science China Earth Sciences 2016年第7期59卷 1454-1462页

作者： SUN chun Qing LIU Jia Qi YOU Hai Tao chu guo Qiang Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences Key Laboratory of Computational Geodynamics College of Earth Science University of Chinese Academy of Sciences

Volcanic glass compositions and tephra layer age are critical for anchoring their sources and correlating among different sites; however, such work may be imprecise when the tephra has varied compositions. The ash from Changbaishan Millennium eruption(940s AD), a widely distributed tephra layer, has been detected in the far-east areas of Russia, the Korean Peninsula, Japan, and in Greenland ice cores. There are some debates on the presence of this tephra from sedimentary archives to the west of Changbaishan volcano, such as lake and peat sediments in the Longgang volcanic field. In this paper, major element compositions for clinopyroxene and Fe-Ti oxides were performed on proximal tephra from Changbaishan and the Millennium eruption ash record in Lake Sihailongwan. Clinopyroxene and Fe-Ti oxides microlites from Sihailongwan show augite-ferroaugite and titanmagnetite compositions, similar to those from dark pumice in Changbaishan proximal tephra, but different from the light grey pumice, which has ferrohedenbergite and ilmenite microlite compositions. This result implies that the tephra recorded in Sihailongwan was mainly from the trachytic eruptive phase of the Millennium eruption, and the rhyolitic eruptive phase made a relatively small contribution to this area. Analyzing clinopyroxene and Fe-Ti oxides microlites is a new method for correlating tephra layers from Changbaishan Millennium eruption.

关键词： Tephra Millennium eruption Changbaishan volcano Sihailongwan Clinopyroxene Fe-Ti oxides

Changes of Soil Water, Organic Matter, and Exchangeable Cations Along a Forest Successional Gradient in Southern China

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Pedosphere 2007年第3期17卷 397-405页

作者： YAN Jun-Hua ZHOU guo-Yi ZHANG De-Qiang chu guo-Wei South China Institute of Botany Chinese Academy of Sciences Guangzhou 510650 （China）

Information on the distribution patterns of soil water content （SWC）, soil organic matter （SOM）, and soil exchangeable cations （SEC） is important for managing forest ecosystems in a sustainable manner. This study investigated how SWC, SOM, and SEC were influenced in forests along a successional gradient, including a regional climax （monsoon evergreen broad-leaved forest, or MEBF）, a transitional forest （coniferous and broad-leaved mixed forest, or MF）, and a pioneer forest （coniferous Masson pine （Pinus rnassoniana） forest, or MPF） of the Dinghushan Biosphere Reserve in the subtropical region of southern China. SWC, SOM, and SEC excluding Ca^2＋ were found to increase in the soil during forest succession, being highest in the top soil layer （0 to 15 cm depth） except for Na^＋. The differences between soil layers were largest in MF. This finding also suggested that the nutrients were enriched in the topsoil when they became increasingly scarce in the soil. There were no significant differences （P = 0.05） among SWC, SOM, and SEC. A linear, positive correlation was found between SWC and SOM. The correlation between SOM and cation exchange capacity （CEC） was statistically significant, which agreed with the theory that the most important factor determining SEC is SOM. The ratio of K^＋ to Na^＋ in the topsoil was about a half of that in the plants of each forest. MF had the lowest exchangeable Ca^2＋ concentration among the three forests and Ca^2＋：K^＋ in MPF was two times higher than that in MF. Understanding the changes of SWC, SOM, and CEC during forest succession would be of great help in protecting all three forests in southern China.

关键词： forest succession soil exchangeable cations soil organic matter soil water content

A New Approach to the Quantum Adiabatic Condition

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Chinese Physics Letters 2012年第10期29卷 5-8页

作者： guo chu DUAN Qian-Heng CHEN Ping-Xing Department of Physics National University of Defense TechnologyChangsha 410073 State Key Laboratory of High Performance Computing National University of Defense TechnologyChangsha 410073

The quantum adiabatic theorem is the basis of adiabatic quantum ***,the exact necessary and sufficient conditions for adiabatic evolution are still under *** discuss the adiabatic condition of a system undergoing a special evolution route,and obtain an explicit formula that is necessary and sufficient for the adiabatic evolution in this *** on this formula,we find that the traditional adiabatic condition is neither sufficient nor ***,we show that no adiabatic process can occur even the evolution speed goes to 0 in some examples,which is surprising since the adiabatic theorem states that if the evolution of a system is slow enough,the adiabatic process could occur.

关键词： computation adiabatic quantum