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H-hop independently submodular maximization problem with curvature

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High-Confidence Computing

High-Confidence Computing 2024年第3期4卷 75-81页

作者： Yang Lv Chenchen Wu dachuan xu Ruiqi Yang beijing Institute for Scientific and Engineering Computing Beijing University of TechnologyBeijing 100124China college of Science Tianjin University of TechnologyTianjin 300382China

The Connected Sensor Problem(CSP)presents a prevalent challenge in the realms of communication and Internet of Things(IoT)*** primary aim is to maximize the coverage of users while maintaining connectivity among K *** the challenge of managing a large user base alongside a finite number of candidate locations,this paper proposes an extension to the CSP:the h-hop independently submodular maximization problem characterized by curvatureα.We have developed an approximation algorithm that achieves a ratio of 1−e−α/(2h+3.α.The efficacy of this algorithm is demonstrated on the CSP,where it shows superior performance over existing algorithms,marked by an average enhancement of 8.4%.

关键词： Internet of things UAV communication Approximation algorithms

A new DNA algorithm to solve graph coloring problem

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Progress in Natural Science:Materials International 2007年第6期17卷 733-738页

作者： Jiang Xingpeng1, Li Yin2, Meng Ya3.and Meng Dazhi2(1. National Laboratory of Pattern Recognition,Institute of Automation, Chinese Academy of sciences, beijing 100080, China 2. college of {3. sciences, beijing university of technology, beijing 100022, China 3. School of Science, beijing Institute of technology, beijing 100081, China) National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100080 China college of applied sciences Beijing University of Technology Beijing 100022 China School of Science Beijing Institute of Technology Beijing 100081 China

Using a small quantity of DNA molecules and little experimental time to solve complex problems successfully is a goal of DNA computing. Some NP-hard problems have been solved by DNA computing with lower time complexity than conventional computing. However, this advantage often brings higher space complexity and needs a large number of DNA encoding molecules. One example is graph coloring problem. Current DNA algorithms need exponentially increasing DNA encoding strands with the growing of problem size. Here we propose a new DNA algorithm of graph coloring problem based on the proof of four-color theorem. This algorithm has good properties of needing a relatively small number of operations in polynomial time and needing a small number of DNA encoding molecules (we need only 6R DNA encoding molecules if the number of regions in a graph is R).

关键词： DNA computing NP-hard problem graph coloring problem.

Targeting the organelle for radiosensitization in cancer radiotherapy

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Asian Journal of Pharmaceutical sciences 2024年第2期19卷 52-71页

作者： Xiaoyan Sun Linjie Wu Lina du Wenhong xu Min han Institute of Pharmaceutics College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China Department of Pharmaceutical sciences Beijing Institute of Radiation MedicineBeijing 100850China Department of Radiation Oncology Key Laboratory of Cancer Prevention and InterventionThe Second Afliated HospitalCollege of MedicineZhejiang UniversityHangzhou 310058China hangzhou Institute of Innovative Medicine Zhejiang UniversityHangzhou 310058China Jinhua Institute of Zhejiang university Jinhua 321299China National Key Laboratory of Advanced Drug Delivery and Release Systems Zhejiang UniversityHangzhou 310058China

Radiotherapy is a well-established cytotoxic therapy for local solid cancers, utilizing high-energy ionizing radiation to destroy cancer cells. However, this method has several limitations, including low radiation energy deposition, severe damage to surrounding normal cells, and high tumor resistance to radiation. Among various radiotherapy methods, boron neutron capture therapy (BNCT) has emerged as a principal approach to improve the therapeutic ratio of malignancies and reduce lethality to surrounding normal tissue, but it remains deficient in terms of insufficient boron accumulation as well as short retention time, which limits the curative effect. Recently, a series of radiosensitizers that can selectively accumulate in specific organelles of cancer cells have been developed to precisely target radiotherapy, thereby reducing side effects of normal tissue damage, overcoming radioresistance, and improving radiosensitivity. In this review, we mainly focus on the field of nanomedicine-based cancer radiotherapy and discuss the organelle-targeted radiosensitizers, specifically including nucleus, mitochondria, endoplasmic reticulum and lysosomes. Furthermore, the organelle-targeted boron carriers used in BNCT are particularly presented. Through demonstrating recent developments in organelle-targeted radiosensitization, we hope to provide insight into the design of organelle-targeted radiosensitizers for clinical cancer treatment.

关键词： Cancer radiotherapy Organelle-target Radiosensitization Boron neutron capture therapy Nanomedicines

Empirical likelihood confidence regions of the parameters in a partially linear single-index model

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Science China Mathematics 2005年第10期48卷 1333-1348页

作者： xuE Liugen~1 & ZHU Lixing~2 1. college of applied {3.,{3.,beijing 100022,China 2. Department of Mathematics,Hong Kong Baptist university,Hong Kong,China college of applied sciences Beijing University of Technology Beijing China Department of Mathematics Hong Kong Baptist University Hong Kong China

In this paper, a partially linear single-index model is investigated, and three empirical log-likelihood ratio statistics for the unknown parameters in the model are suggested. It is proved that the proposed statistics are asymptotically standard chi-square under some suitable conditions, and hence can be used to construct the confidence regions of the parameters. Our methods can also deal with the confidence region construction for the index in the pure single-index model. A simulation study indicates that, in terms of coverage probabilities and average areas of the confidence regions, the proposed methods perform better than the least-squares method.

关键词： partially linear single-index model, empirical likelihood, confidence region, chi-square distribution, coverage probability.

Empirical likelihood-based inference in a partially linear model for longitudinal data

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Science China Mathematics 2008年第1期51卷 115-130页

作者： xuE LiuGen~(1+) & ZHU LiXing~2 1 college of applied {3., {3., beijing 100022, China 2 Department of Mathematics, Hong Kong Baptist university, Hong Kong, China college of applied sciences Beijing University of Technology Beijing China Department of Mathematics Hong Kong Baptist University Hong Kong China

A partially linear model with longitudinal data is considered, empirical likelihood to infer- ence for the regression coefficients and the baseline function is investigated, the empirical log-likelihood ratios is proven to be asymptotically chi-squared, and the corresponding confidence regions for the pa- rameters of interest are then constructed. Also by the empirical likelihood ratio functions, we can obtain the maximum empirical likelihood estimates of the regression coefficients and the baseline function, and prove the asymptotic normality. The numerical results are conducted to compare the performance of the empirical likelihood and the normal approximation-based method, and a real example is analysed.

关键词： partially linear model empirical likelihood confidence region longitudinal data 62G05 62G15 62G20

Threshold quantum secure direct communication without entanglement

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Science China(Physics,Mechanics & Astronomy) 2008年第2期51卷 176-183页

作者： YANG YuGuang1,3.& WEN QiaoYan2 1 college of Computer Science and technology, beijing university of technology, {3., China 2 School of Science, beijing university of Posts and Telecommunications, beijing 100876, China 3.State Key Laboratory of Information Security (Graduate School of Chinese Academy of sciences), beijing 100049, China college of Computer Science and technology Beijing University of Technology Beijing China State Key Laboratory of Information Security (Graduate School of Chinese Academy of sciences) Beijing China School of Science Beijing University of Posts and Telecommunications Beijing China

For the first time, a threshold quantum secure direct communication (TQSDC) scheme is presented. Similar to the classical Shamir's secret sharing scheme, the sender makes n shares, S1, …, Sn of secret key K and each receiver keeps a share secretly. If the sender wants to send a secret message M to the receivers, he en-codes the information of K and M on a single photon sequence and sends it to one of the receivers. According to the secret shares, the t receivers sequentially per-form the corresponding unitary operations on the single photon sequence and ob-tain the secret message M. The shared shares may be reusable if it can be judged that there is no eavesdropper in line. We discuss that our protocol is feasible with current technology.

关键词： quantum secure direct communication threshold secure direct communication quantum secret sharing

Existence of solutions for the dynamic equation of ferrimagnets

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Progress in Natural Science:Materials International 2007年第11期17卷 1279-1283页

作者： Zeng Ming1, Guo Boling2 and Cheng Caozong1(1. college of applied sciences, {3., beijing 100022, China 2. Center for Nonlinear Studies, Institute of applied Physics and Computational Mathematics, beijing 100088, China) college of applied sciences Beijing University of Technology Beijing 100022 China Center for Nonlinear Studies Institute of Applied Physics and Computational Mathematics Beijing 100088 China

Ferrimagnet is a kind of basic and important multi-sublattice magnet material. It has attracted more and more attention of physicists and mathematicians. Many results of solitons and numerical computations on this topic have appeared. In this article, the dynamic equation for an isotropic ferrimagnet with two non-equivalent sublattices is studied, existence of weak solutions in multi dimension case is proved through the penalized method, the uniqueness and smoothness of the solution in one dimension case are also obtained by the relation between this equation and hyperbolic equation.

关键词： ferrimagnet weak solutions penalized method finite difference method

Multiparty simultaneous quantum identity authentication with secret sharing

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Science China(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2,WEN QiaoYan3.& ZhanG Xing4,5 1 college of Computer Science and technology,{3.,{3.,China 2 State Key Laboratory of Information Security (Graduate university of the Chinese Academy of sciences),beijing 100049,China 3.School of Science,beijing university of Posts and Telecommunications,beijing 100876,China 4 Institute of Electronic technology,Information Engineering university,Zhengzhou 450004,China 5 Trusted Computing Laboratory,{3.,{3.,China college of Computer Science and technology Beijing University of Technology Beijing China State Key Laboratory of Information Security (Graduate university of the Chinese Academy of sciences) Beijing China School of Science Beijing University of Posts and Telecommunications Beijing China Institute of Electronic technology Information Engineering University Zhengzhou China Trusted Computing Laboratory Beijing University of Technology Beijing China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

Role of gallium wetting layer in high-quality ZnO growth on sapphire (0001) substrates

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Science China(Physics,Mechanics & Astronomy) 2004年第5期47卷 612-620页

作者： ZENG Zhaoquan1,3. WANG Yong2, du Xiaolong1, MEI Zengxia1, KONG Xianghe3. JIA Jinfeng1, xuE Qikun1 & ZhanG Ze2, 4 1. State Key Laboratory for Surface Physics, Institute of Physics, Chinese Academy of {3., beijing 100080, China 2. Laboratory of Electron Microscopy, Institute of Physics, Chinese Academy of {3., beijing 100080, China 3. college of Physics and Engineering, Qufu Normal university, Qufu 273.65, China 4. beijing university of technology, beijing 100022, China State Key Laboratory for Surface Physics Institute of Physics Chinese Academy of Sciences Beijing China college of Physics and Engineering Qufu Normal University Qufu China Laboratory of Electron Microscopy Institute of Physics Chinese Academy of Sciences Beijing China beijing university of technology Beijing China

A Ga wetting layer was used to modify the surface structure of sapphire (0001) substrate to prepare high-quality ZnO film by radio frequency plasma-assisted molecule beam epitaxy. We found that this Ga layer plays a crucial role in eliminating 3. rotation domains, controlling polarity and decreasing defect density in ZnO epilayers, as demonstrated by in situ reflection high energy electron diffraction, ex situ high resolution X-ray diffraction and high resolution cross-sectional transmission electron microscopy. Zn-polar film of ZnO was determined by convergent beam electron diffraction. A Ga bilayer model is proposed to understand the effects of the Ga wetting layer on high-quality ZnO growth.

关键词： Ga wetting layer, sapphire, polarity, defect density, zinc oxide, rf-MBE, RHEED, HRXRD, TEM, CBED.