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Semi-blind compressed sensing via adaptive dictionary learning and one-pass online extension

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Science China(Information Sciences) 2021年第9期64卷 235-237页

作者： di ma Songcan CHEN College of Computer Science and Technology MIIT Key Laboratory of Pattern Analysis and Machine Intelligence Nanjing University of Aeronautics and Astronautics

Dear editor,Compressed sensing(CS) [1], as an efficient data acquisition paradigm, has attracted much attentions since it came up. The fundamental principle of CS is that a signal, which is sparse under some sparsity basis, can be efficiently acquired and accurately recovered via far fewer measurements than the traditional Shannon-Nyquist sampling. Since the number of measurements is much smaller than the number of signal coefficients,

关键词： Information Systems and Communication Service

Identity-Based Encryption on RSA Without Pairings and Key Escrow

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Chinese Journal of Electronics 2014年第4期23卷 842-850页

作者： ZHU Yan WANG Shanbiao ma di FENG Rongquan School of Computer and Communication Engineering University of Science and Technology Beijing School of mathematical Sciences Peking University Department of Computer and Information Science University of Michigan-Dearborn

We propose a new construction of identitybased encryption without key escrow over the tradition RSA cryptosystems. The security of our scheme follows from the decisional diffie-Hellman assumption and the difficulty of Modular inversion hidden number problem with error(MIHNPw E), which can be seen as a generalization of the modular inversion hidden number problem. We give an analysis on the hardness of MIHNPw E by lattice techniques. In our construction, we generate each user’s partial private key in the form of an MIHNPw E instance. The hardness of MIHNPw E provides our scheme with resistance against key-collusion attacks from any number of traitors. Our prototype implementation of the proposed scheme shows that it can be more computation efficient and easy-to-implementation than the influential pairingfriendly elliptic-curve based IBE scheme.

关键词： Identity-based encryption Key escrow Hidden number problem with error

Lattice-based key exchange on small integer solution problem

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Science China(Information Sciences) 2014年第11期57卷 150-161页

作者： WANG ShanBiao ZHU Yan ma di FENG RongQuan School of mathematical Sciences Peking University School of Computer and Communication Engineering University of Science and Technology Beijing Department of Computer and Information Science University of Michigan-Dearborn

In this paper, we propose a new hard problem, called bilateral inhomogeneous small integer solution(Bi-ISIS), which can be seen as an extension of the small integer solution problem on lattices. The main idea is that, instead of choosing a rectangle matrix, we choose a square matrix with small rank to generate Bi-ISIS problem without affecting the hardness of the underlying SIS problem. Based on this new problem, we present two new hardness problems: computational Bi-ISIS and decisional problems. As a direct application of these problems, we construct a new lattice-based key exchange(KE) protocol, which is analogous to the classic diffieHellman KE protocol. We prove the security of this protocol and show that it provides better security in case of worst-case hardness of lattice problems, relatively efficient implementations, and great simplicity.

关键词： cryptography lattices small integer solutions key exchange protocol secure communications

Practical decoy-state quantum secure direct communication

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Science China(Physics,Mechanics & Astronomy) 2021年第12期64卷 68-75页

作者： Xin Liu Zijian Li di Luo Chunfeng Huang di ma Minming Geng Junwei Wang Zhenrong Zhang Kejin Wei Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Multimedia Communications and Network Technology School of ComputerElectronicsand InformationGuangxi UniversityNanning 530004China CAS Quantum Network Co. LtdShanghai 201315China

Quantum secure direct communication(QSDC) has been demonstrated in both fiber-based and free-space channels using attenuated lasers. Decoy-state QSDC by exploiting four decoy states has been proposed to address the problem of photon-numbersplitting attacks caused by the use of attenuated lasers. In this study, we present an analysis of the practical aspects of decoy-state QSDC. First, we design a two-decoy-state protocol that only requires two decoy states, thereby significantly reducing experimental complexity. Second, we successfully perform full parameter optimization for a real-life QSDC system by introducing a genetic algorithm. Our simulation results show that the two-decoy-state protocol could be the best choice for developing a practical QSDC system. Furthermore, full optimization is crucial for a high-performance QSDC system. Our work serves as a major step toward the further development of practical decoy-state QSDC systems.

关键词： quantum secure direct communication decoy-state method full parameter optimization

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mass spectrometry-based proteomics and peptidomics for systems biology and biomarker discovery

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Frontiers in Biology 2012年第4期7卷 313-335页

作者： Robert CUNNINGHAM di ma Lingjun LI Department of Chemistry University of Wisconsin-Madison 777 Highland Avenue 1101 University Avenue Madison WI 53706 USA School of Pharmacy University of Wisconsin-Madison 777 Highland Avenue Madison WI 53 705-2222 USA

The scientific community has shown great interest in the field of mass spectrometry-based proteomics and peptidomics for its applications in biology. Proteomics technologies have evolved to produce large data sets of proteins or peptides involved in various biologic and disease progression processes generating testable hypothesis for complex biologic questions. This review provides an introduction to relevant topics in proteomics and peptidomics including biologic material selection, sample preparation, separation techniques, peptide fragmentation, post-translational modifications, quantification, bioinformatics, and biomarker discovery and validation. In addition, current literature, remaining challenges, and emerging technologies for proteomics and peptidomics are presented.

关键词： mass spectrometry proteomics peptidomics review post-translational modifications fragmentation separation,protein quantitation sample preparation biomarker discovery validation bioinforrnatics

The 2022 record-breaking high temperature in China:Sub-seasonal stepwise enhanced characteristics,possible causes and its predictability

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Advances in Climate Change Research 2023年第5期14卷 651-659页

作者： Yuan-Yuan ma Yi-Ting CHEN Xiao-Xue HU Qian-Rong ma Tai-Chen FENG Guo-Ling FENG di ma Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Physical Science and Technology Yangzhou UniversityYangzhou 225127China College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000China School of Atmospheric Sciences Key Laboratory of Tropical Atmosphere-Ocean SystemMinistry of EducationSun Yat-sen UniversityZhuhai 519082China Southern marine Science and Engineering Guangdong Laboratory Zhuhai 519082China

In the summer of 2022,an unprecedented and long-lasting high temperature swept central-eastern China,causing significant societal ***,the sub-seasonal characteristics,causes and predictability of this extreme high temperature event are not well *** on the locations,intensities and causes of the high temperature,we divided it into three stages:early(13 June-3 July),sustained(4-28 July),and enhancement(29 July-30 August)*** high temperature during the early stage mainly occurred in north-central China with an anomaly of 2.5℃compared with climatology(1981-2010),while the last two stages occurred in the middle and lower Yangtze River Basin with anomalies of 2.8 and 3.8℃*** high temperature during the three stages were all regulated by the strengthening and westward extension of the western Pacific subtropical high(WPSH)but involved different physical *** the early stage,it was mainly caused by the anticyclones over the Mongolia and Northwest Pacific and enhanced by the minor impact of *** the sustained stage it was influenced by relatively more stronger WPSH and South Asia high(SAH)and the relatively minor impact of the anticyclone over the north-western South *** the enhancement stage,the high temperature was mainly caused by a combination of the record-breaking WPSH and SAH and the strong European blocking ***,the exceptionally powerful WPSH was well correlated with the sea surface temperature gradient induced by the developing La Niñ*** ECMWF and NCEP models reasonably predicted the location and intensity of the high temperature in the early stage,but poorly predicted that in the sustained and enhancement stages partly because of the failure prediction of the WPSH's enhancement and westward *** ECMWF model's more accurate prediction of the WPSH may contribute to its better forecasting of the heatwaves.

关键词： High temperature Sub-seasonal characteristics Western Pacific subtropical high La Niña development phase Predictability

Zeolite A enhanced chitosan films with high water absorption ability and antimicrobial activity

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Chinese Journal of Chemical Engineering 2021年第5期34卷 337-343页

作者： Jie Gong Fei Tong Bin Wang di ma Chunyong Zhang Jinlong Jiang Lixiong Zhang College of Chemical and Environmental Engineering Jiangsu University of TechnologyChangzhou 213001China Jiangsu Provincial Key Laboratory of Palygorskite Science and Applied Technology Faculty of Chemical EngineeringHuaiyin Institute of TechnologyHuai'an 223003China State Key Laboratory of materials-Oriented Chemical Engineering College of Chemistry and Chemical EngineeringNanjing Tech UniversityNanjing 210009China

Zeolite A/CS xerogel hybrid films were prepared by in-situ crystallization method with uniform structure and good *** hybrid films prepared from the precursor films dried at 50℃showed zeolite A was well *** hybrid films show high water absorption,good elastic strength and Young *** antimicrobial ability of the hybrid films was investigated after Ag^(+)-ion *** Ag^(+)-exchanged hybrid films with 35%(mass)content of zeolite A showed the highest antimicrobial activity,which could reduce the concentration of the microbial to zero after 7 h.

关键词： Zeolite A Hybrid film Water absorption Antimicrobial activity

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Is there an optimal time to initiate adjuvant chemotherapy to predict benefit of survival in non-small cell lung cancer?

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Chinese Journal of Cancer Research 2017年第3期29卷 263-271页

作者： Yutao Liu Xiaoyu Zhai Junling Li Zhiwen Li di ma Ziping Wang Department of Medical Oncology National Cancer Center/Cancer Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Institute of Reproductive & Child Health Peking University Ministry of Health Key Laboratory of Reproductive Health Department of Epidemiology and Biostatistics School of Public Health Peking University Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing) Department of Thoracic Medical Oncology Peking University Cancer Hospital &Institute

Objective: Adjuvant chemotherapy (AC) after curative resection is known to improve the survival of patients with non-small cell lung cancer (NSCLC); however, few studies have reported the correlation between the time to initiation of AC (TTAC) and survival in NSCLC patients. Methods: The clinical data of 925 NSCLC patients who received curative resection and post-operative AC at the Cancer Hospital of Chinese Academy of Medical Sciences between 2003 and 2013 were retrospectively analyzed. TTAC was measured from the date of surgery to the initiation of AC. disease-free survival (DFS) was defined as the duration from surgery to the time of tumor recurrence or last follow-up evaluation. The optimal cut-off value of TTAC was determined by maximally selected log-rank statistics. The DFS curve was estimated using the Kaplan-Meier method, and the Cox proportional hazards regression model was used to identify risk factors independently associated with DFS. Propensity score matching (PSM) was performed for survival analysis using the match data. Results: The optimal discriminating cut-off value of TTAC was set at d 35 after curative resection based on which the patients were assigned into two groups: group A ( 35 d). There was no significant difference in the DFS between the two groups (P=0.246), indicating that the TTAC is not an independent prognostic factor for DFS. A further comparison continued to show no significant difference in the DFS among 258 PSM pairs (P=0.283). Conclusions: There was no significant correlation between the TTAC and DFS in NSCLC patients. Studies with larger samples are needed to further verify this conclusion.

关键词： Non-small cell lung cancer (NSCLC) adjuvant chemotherapy time to adjuvant chemotherapy(TTAC) disease-free survival

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Controls on the facies and architecture evolution of a fan delta in Qinghai Lake,China

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Frontiers of Earth Science 2024年第3期18卷 488-508页

作者： di ma Xinghe YU Shunli LI Zhijie ZHANG Chao FU Hongwei SUN Chun LIU School of Energy China University of GeosciencesBeijing 100083China Research Institute of Petroleum Exploration and Development Hangzhou 310000China

Deltaic sedimentary systems form the most favorable hydrocarbon reservoirs in continental faulted lacustrine basins,and their types and controlling factors directly affect the distribution of *** systematic study of typical modern delta deposition provides significant guidance regarding the distribution of oil and gas reservoirs in the *** this reason,the Heima River delta in Qinghai Lake,which features multiple sediment sources and clear sedimentary evolution stages,was selected for this research.A detailed study of the sedimentology and architectural characteristics of the Heimahe delta in Qinghai Lake was conducted.A total of 4 types of gravel facies,4 types of sand facies,and 2 types of mud facies were *** study also focuses on recognizing the architectural elements within channels and *** delta plain features debris-flow,switched,and migrated channels and vertical and bilateral aggradation *** delta front features migrated and filled channels and bilateral and lateral aggradation ***-two representative outcrop sections were *** observation and analysis of these sections revealed three stages:the progradation to aggradation(PA)stage,in which the deposits show evidence of sigmoid-type and coarse-grained sedimentation;the retrogradation(R)stage,which is characterized by imbricated regression;and the aggradation to progradation and degradation(APD)stage,which is characterized by a terraced-stepping,progression stacking *** on the integrated analysis of the sedimentary environment,outcrop lithofacies associations,architecture stacking patterns,fossils and bioclasts,we identified diverse depositional associations and constructed a sedimentary evolution model of the depositional system in this *** suggest that the depositional system transitioned from an early single-provenance gravel-rich fan delta to a multi-provenance mud-rich delta and that two factors mainly controlled the transitio

关键词： Qinghai Lake Heimahe Delta sedimentary pattern controlling factor Quaternary