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Budget Allocation for Maximizing Viral Advertising in Social Networks

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Journal of Computer Science & Technology 2016年第4期31卷 759-775页

作者： Bo—LeiZhang Zhu-zhong Qian wen-zhong li Bin Tang Sang-Lu Lu Xiaoming Fu State Key Laboratory for Novel Software Technology Nanjing University Nanjing 210023 China Institute of Computer Science University of G5ttingen G5ttingen 37077 Germany

Viral advertising in social networks has arisen as one of the most promising ways to increase brand awareness and product sales. By distributing a limited budget, we can incentivize a set of users as initial adopters so that the advertising can start from the initial adopters and spread via sociM links to become viral. Despite extensive researches in how to target the most influential users, a key issue is often neglected： how to incentivize the initial adopters. In the problem of influence maximization, the assumption is that each user has a fixed cost for being initial adopters, while in practice, user decisions for accepting the budget to be initial adopters are often probabilistic rather than deterministic. In this paper, we study optimal budget allocation in social networks to maximize the spread of viral advertising. In particular, a concave probability model is introduced to characterize each user＇s utility for being an initial adopter. Under this model, we show that it is NP-hard to find an optimal budget allocation for maximizing the spread of viral advertising. We then present a novel discrete greedy algorithm with near optimal performance, and further propose scaling-up techniques to improve the time-efficiency of our algorithm. Extensive experiments on real-world social graphs are implemented to validate the effectiveness of our algorithm in practice. The results show that our algorithm can outperform other intuitive heuristics significantly in almost all cases.

关键词： social network influence maximization information diffusion submodular optimization

Joint multiple parameters estimation for coherent chirp signals using vector sensor array

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Science in China(Series F) 2008年第1期51卷 93-100页

作者： wen zhong li liPing CHEN TianQi ZHANG XiXiang School of Electronic Engineering University of Electronic Science and Technology of China Chengdu 610054 China

In this paper, an algorithm is proposed to estimate starting frequency （SF）, chirp rate （CR）, 2-D direction-of-arrivals （DOA） and polarization of coherent chirp signals with vector sensor arrays. The fractional Fourier transformation （FRFT） is used to estimate SF and CR of chirp signals in this method. And a new correlation matrix is reconstructed to suppress the noise. The property of the vector sensor array is employed to solve the problem of insufficient rank from signal coherence. The L-shaped uniform array of expend aperture is used to improve the precision of es- timation, and the method of solving the ambiguity of angle under the condition of coherent signals is presented. The performance of this algorithm is compared with that of spatial smoothing method to verify the efficacy of this approach.

关键词： vector sensor array FRFT coherence

Next POI Recommendation Based on Location Interest Mining with Recurrent Neural Networks

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Journal of Computer Science & Technology 2020年第3期35卷 603-616页

作者： Ming Chen wen-zhong li lin Qian Sang-Lu Lu Dao-Xu Chen State Key Laboratory for Novel Software Technology Nanjing UniversityNanjing 210023China Sino-German Institutes of Social Computing Nanjing UniversityNanjing 210023China State Grid Electric Power Research Institute NARI Group CorporationNanjing 211000China

In mobile social networks,next point-of-interest(POI)recommendation is a very important function that can provide personalized location-based services for mobile *** this paper,we propose a recurrent neural network(RNN)-based next POI recommendation approach that considers both the location interests of similar users and contextual information(such as time,current location,and friends’preferences).We develop a spatial-temporal topic model to describe users’location interest,based on which we form comprehensive feature representations of user interests and contextual *** propose a supervised RNN learning prediction model for next POI *** based on real-world dataset verify the accuracy and efficiency of the proposed approach,and achieve best F1-score of 0.196754 on the Gowalla dataset and 0.354592 on the Brightkite dataset.

关键词： location interest location-based service point-of-interest(POI)recommendation mobile social network

Fabrication of Two-dimensional Monolayer and One-dimensional Wire of Zn-tetra-[3,5-di-t-butylphenyl]-porphyrin on Cu(100) Surface

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Chinese Journal of Structural Chemistry 2006年第8期25卷 992-996页

作者： QIAN li-Ping WANG Xian XU Di WANG Zhou-Feng JIANG zhong-Jie DENG wen-li College of Materials Science and Engineering South China University of Technology Guangzhou 510640 China

We describe in this paper the fabrication of two- and one-dimensional nanostructures with organic molecular beam epitaxy （OMBE） principle based on controlled selfassembly by using adsorbate-substrate and intennolecular interactions that are important in molecular fabrication. Cu（100） single crystal was used as substrate in fabricating molecular nanostructures. Scanning tunneling microscopy （STM） experiments confirmed that Zn-tetra- [3,5-di-t-butylphenyl]porphyrin-molecules can be used to fabricate both monolayer and molecular wire on Cu（100） surface simultaneously, and the latter is arranged on the terrace edges. We herein briefly discuss the selectivity in terms of a mechanism in which the highest occupied and lowest unoccupied molecular orbitals （HOMO and LUMO） of the molecules interact with the surface.

关键词： fabrication two-dimensional monolayer one-dimensional molecular wire Zn-tetra-[3,5-di-t-butylphenyl]porphyrin

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海南的农业资源特点和热带农业发展道路选择

农业现代化研究 2009年第3期30卷 306-309页

作者：钟利文海南大学园艺园林学院海南儋州571737

热带农业的发展关系海南经济社会发展的全局,海南热带农业发展道路的选择关系到如何充分合理利用自然资源、调整产业结构、提高劳动者素质和促进城乡经济一体化,事关实现全省全面小康、建设和谐社会的进程。本文通过分析海南的区位特征... 详细信息

热带农业的发展关系海南经济社会发展的全局,海南热带农业发展道路的选择关系到如何充分合理利用自然资源、调整产业结构、提高劳动者素质和促进城乡经济一体化,事关实现全省全面小康、建设和谐社会的进程。本文通过分析海南的区位特征和农业自然资源特点,阐明了海南热带农业必须走坚持特色发展、优化产业布局、以市场为导向、产业化经营、依靠科技支撑和生态协调的现代化发展之路。

关键词：农业资源热带农业道路选择海南省

Outpatient Surgery in zhongshan Ophthalmic Center： Promise and Problems

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Chinese Medical Journal 2017年第13期130卷 1623-1624页

作者： Zhi-Gang Fan Dan-Dan Zhang zhong-wen li Yao Yang Xiao-Feng lin State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat-sen University Guangzhou Guangdong 510060 China

To the Editor： The Chinese government is actively advocating medical reform, aiming at reducing medical costs, and improving service quality. As to ophthalmology, transition from traditional hospitalized surgery to a predominant outpatient mode could be a solution. zhongshan Ophthalmic Center （ZOC） is one of the largest and leading ophthalmic centers in China,

关键词： Outpatient Surgery zhongshan Ophthalmic Center Promise and Problems

Endoscopic management of ureteriovesical anastomosis obstruction in transplanted kidneys

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Endoscopic management of ureteriovesical anastomosis obstruc...

第十五届全国泌尿外科学术会议

作者： ZENG Guo-hua, zhong wen,li Xun,YUAN Jian,YANG Hou-meng, CHEN wen-zhong. 广州医学院第一附属医院微创外科中心泌尿外科

Objective: Ureterovesical anastomosis obstruction in transplanted kidneys remains challenge to urologist. The complicated adjacent anatomy and high risk to infection was the disadvantage to open operation reconstruction. We reported our experience of endoscopic management for these cases. Material and methods:Between October 2000 and July 2007, 5 men and 2 women with ureterovesical anastomotic

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局部染毒皮肤洗消的实验研究

消防科学与技术 2012年第2期31卷 185-189页

作者：钟文立南平市消防支队福建南平353000

介绍化学事故洗消的程序和方法,综述了洗消剂种类及选择原则。用苯和甲苯两种化学毒物直接沾染皮肤,分别以水、吸附颗粒、吸液颗粒、活性炭作为洗消剂进行洗消,同时用AreaRAE RDK快速部署系统进行实时检测,分析洗消前后皮肤表面毒物浓... 详细信息

介绍化学事故洗消的程序和方法,综述了洗消剂种类及选择原则。用苯和甲苯两种化学毒物直接沾染皮肤,分别以水、吸附颗粒、吸液颗粒、活性炭作为洗消剂进行洗消,同时用AreaRAE RDK快速部署系统进行实时检测,分析洗消前后皮肤表面毒物浓度变化情况,测定各类洗消剂对化学毒物的洗消效果,在此基础上确定最适合的洗消剂以及洗消剂的用量和洗消时间。实验结果表明,只要水对苯和甲苯的洗消时间足够长,就能够将皮肤表面的染毒物质彻底消除。吸附颗粒、吸液颗粒、活性炭三种固体洗消剂都能够有效地消除皮肤表面的沾染物。对苯的洗消,活性炭效果最好,其次是吸液颗粒和吸附颗粒。对甲苯的洗消,则是吸附颗粒效果最好,其次是吸液颗粒和活性炭。

关键词：染毒皮肤 AreaRAE RDK快速部署系统洗消剂洗消

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广交会对我国外贸的影响因素分析

特区经济 2010年第3期 33-34页

作者：钟汶利江苏大学财经学院江苏镇江212013 江苏大学

广交会是我国被公认的规模最大、效果最好、层次最高的综合性国际贸易盛会,作为中国会展业的突出代表,也非常充分地应证了会展业对我国经济的积极促进作用。本文首先通过对广交会的相关情况进行大量文献收集,经过科学的分析和思考,总结... 详细信息

广交会是我国被公认的规模最大、效果最好、层次最高的综合性国际贸易盛会,作为中国会展业的突出代表,也非常充分地应证了会展业对我国经济的积极促进作用。本文首先通过对广交会的相关情况进行大量文献收集,经过科学的分析和思考,总结了广交会对我国国际贸易的三大影响因素。

关键词：广交会外贸影响因素