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Active User and Data Detection for Uplink Grant-free NOMA Systems

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China Communications 2020年第11期17卷 12-28页

作者： Donghong Cai Jinming Wen Pingzhi fan Yanqing Xu Lisu Yu 无 The College of Cyber Security Jinan UniversityGuangzhou 510632China The Institute of Mobile Communications Southwest Jiaotong UniversityChengdu 610031China The State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China The School of Information Engineering Nanchang UniversityNanchang 330031China

This paper proposes some low complexity algorithms for active user detection(AUD),channel estimation(CE)and multi-user detection(MUD)in uplink non-orthogonal multiple access(NOMA)systems,including single-carrier and multi-carrier *** particular,we first propose a novel algorithm to estimate the active users and the channels for single-carrier based on complex alternating direction method of multipliers(ADMM),where fast decaying feature of non-zero components in sparse signal is *** importantly,the reliable estimated information is used for AUD,and the unreliable information will be further handled based on estimated symbol energy and total accurate or approximate number of active ***,the proposed algorithm for AUD in single-carrier model can be extended to multi-carrier case by exploiting the block sparse ***,we propose a low complexity MUD detection algorithm based on alternating minimization to estimate the active users’data,which avoids the Hessian matrix *** convergence and the complexity of proposed algorithms are analyzed and discussed *** results show that the proposed algorithms have better performance in terms of AUD,CE and ***,we can detect active users perfectly for multi-carrier NOMA system.

关键词： non-orthogonal multiple access massive connection active user detection channel estimation multi-user detection and alternating direction method of multipliers

One-dimensional nonlinear consolidation analysis of soil with continuous drainage boundary

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Journal of Central South University 2022年第1期29卷 270-281页

作者： ZONG meng-fan TIAN Yi LIANG Rong-zhu WUWen-bing XU Mei-juan MEI Guo-xiong Faculty of Engineering China University of GeosciencesWuhan 430073China College of Civil Engineering and Architecture Guangxi UniversityNanning 530004China Geotechnical Research Centre Department of Civil and Environmental EngineeringWestern UniversityLondonONN6A5B9Canada

Following the assumptions proposed by MESRI and ROKHSAR,the one-dimensional nonlinear consolidation problem of soil under constant loading is studied by introducing continuous drainage *** numerical solution is derived by using finite difference method and its correctness is assessed by comparing with existing analytical and numerical *** on the present solution,the effects of interface parameters,stress ratios(i.e.,final effective stress over initial effective stress,N_(σ))and the ratio c_(c)/c_(k)of compression index to permeability index on the consolidation behavior of soil are studied in *** results show that,the characteristics of one-dimensional nonlinear consolidation of soil are not only related to c_(c)/c_(k)and N_(σ),but also related to boundary *** the engineering practice,the soil drainage rate of consolidation process can be designed by adjusting the values of interface parameters.

关键词： one-dimensional nonlinear consolidation continuous drainage boundary finite difference method interface parameter

Application of Response Surface Methodology for Analysis of Reheat Steam Temperatures in a Double Reheat Coal-Fired Boiler

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Journal of Thermal Science 2022年第6期31卷 2203-2215页

作者： ZHANG Jian XU Wei ZHANG Zhongxiao fan Haojie WU Xiaojiang DONG Jiancong Institute of Thermal Energy Engineering School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Energy Research Institute Nanjing Institute of TechnologyNanjing211167China

For the improvement of reheat steam quality and performance of double reheat coal-fired utility boiler under wide load operation, a variety of temperature regulation ways were utilized to adjust the energy distribution between different heating surfaces. In this paper, thermodynamic calculation based on the fundamental heat transfer theory was conducted for the analysis of temperature regulation strategy effects to steam temperature. In consideration of the specific overlapping heating surface arrangement, the compartment model was adopted to solve this problem. Response surface methodology(RSM) was used to analysis the effect of each temperature regulating variables on the steam temperature and boiler efficiency;then the polynomial model was fitted to predict the primary and secondary steam temperature simultaneously. Results showed that the flue gas recirculation rate has a relatively significant influence on the steam temperature, the maximum temperature deviation between fitting value and calculation value is 3.85℃ in 75% THA;the quadratic model can well predict the steam temperature under different operation conditions in wide load change. The variation of flue gas baffle has a significant influence on the boiler efficiency, compared to the flue gas recirculation and angle of burner oscillation. The influence of various factors on the reheat steam temperature is flue gas baffle > flue gas recirculation > angle of burner oscillation.

关键词： reheat steam temperature flue gas baffle flue gas recirculation response surface methodology coal-fired boiler

Effect of strain rate on microstructure and mechanical properties of spray-formed Al-Cu-Mg alloy

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Transactions of Nonferrous Metals Society of China 2022年第4期32卷 1096-1104页

作者： Tong SHEN Cai-he fan Ze-yi HU Qin WU Yu-meng NI Yu-zhou CHEN College of Materials and Advanced-Manufacturing Hunan University of TechnologyZhuzhou 412007China Anhui Jianye Science and Technology Co. Ltd.Huaibei 235000China Hunan Zhirong Science and Technology Co. Ltd.Zhuzhou 412000China

Transmission electron microscopy(TEM),X-ray diffraction(XRD),electron backscattered diffraction(EBSD),and tensile tests were used to study the effects of strain rates(0.1,1 and 9.1 s^(-1))on the microstructure and mechanical properties of spray-formed Al-Cu-Mg alloys during large-strain rolling at 420℃.Results show that during hot rolling,the proportion of high-angle grain boundaries(HAGBs)and the degree of dynamic recrystallization(DRX)initially increase and then decrease,whereas the average grain size and dislocation density show the opposite trend with the increase of the strain *** addition,the number of S′phases in the matrix decreases,and the grain boundary precipitates(GBPs)become coarser and more discontinuous as the strain rate *** the strain rate increases from 0.1 to 9.1 s^(-1),the tensile strength of the alloy decreases from 492.45 to 427.63 MPa,whereas the elongation initially increases from 12.1%to 21.8%and then decreases to 17.7%.

关键词： spray forming Al-Cu-Mg alloy strain rate microstructure mechanical properties

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飞秒脉冲激光器中色散补偿膜的设计

光子学报 2005年第5期34卷 730-733页

作者：廖春艳邵建达范正修中国科学院上海光学精密机械研究所上海201800

阐述了用光学薄膜进行色散补偿的基本原理,介绍了设计的基本过程.根据Ti∶ Sapphire飞秒激光器中腔内色散补偿的要求,设定了色散补偿目标,通过计算机优化,得到了一种40层的Ta2O5/SiO2介质膜系.该膜系能在720～870 nm范围获得大于99.5%... 详细信息

阐述了用光学薄膜进行色散补偿的基本原理,介绍了设计的基本过程.根据Ti∶ Sapphire飞秒激光器中腔内色散补偿的要求,设定了色散补偿目标,通过计算机优化,得到了一种40层的Ta2O5/SiO2介质膜系.该膜系能在720～870 nm范围获得大于99.5%的反射率,在510～550 nm获得大于90%的透射率,在740～850 nm提供较平滑的-40 fs2的群延迟色散.这样的结果经过7次反射后,可以补偿5-mm Ti∶ sapphire晶体产生的绝大部分群延迟色散.

关键词：光学薄膜飞秒脉冲群延迟色散色散补偿

BreedingAIDB: A database integrating crop genome-to-phenotype paired data with machine learning tools applicable to breeding

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Plant Communications 2024年第7期5卷 12-15页

作者： Zijie Shen Enhui Shen Kun Yang Zuoqian fan Qian-Hao Zhu Longjiang fan Chu-Yu Ye Hainan Institute Zhejiang UniversitySanya 572025China Institute of Crop Science&Institute of Bioinformatics College of Agriculture&BiotechnologyZhejiang UniversityHangzhou 310058China CSIRO Agriculture and Food CanberraACT 2601Australia

Machine learning(ML)is one of the key technologies for next-generation breeding,and“big data”is the cornerstone for development of ML algorithms that are applicable to crop breeding ***,there is a shortage of databases containing phenotype data and corresponding genomic data,i.e.,genome-to-phenotype(G2P)paired data,that can be used in the development of ML algorithms for *** fill this gap,we constructed a user-friendly database named the BreedingAIDB(http://***/BreedingAIDB)to provide breeders and ML experts with easily accessible G2P paired data for crops,as well as ML tools.

关键词： database learning breeding

Nutrient Deficiency Affects Root Architecture of Young Seedlings of Malus hupehensis (Pamp) Rehd. Under Conditions of Artificial Medium Cultivation

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Agricultural Sciences in China 2007年第3期6卷 296-303页

作者： fan Wei-guo YANG Hong-qiang College of Horticulture Science and Engineering Shandong Agricultural University Taian 271018 P.R.China

What the researchers go in for is to establish models between root architecture （RA） changes and nutrition, mold ideal root architecture of apple trees, improve the nutrient uptake efficiency, and further explore the functional mechanism of nutrient elements during the course of RA construction. The cultivation system of filter paper is utilized to research the effect of nutrient deficiency on the RA of Malus hupehensis （Pamp.） Rehd. There may be eight types of RA. In complete Hogland solution, the main type of RA is ＂lateral roots clustering in the upper and middle regions of primary root＂. With the lack of P, K or Ca, the main type of RA is ＂lateral roots clustering in the upper region primary root＂, and the ＂lateral roots clustering in the upper and middle regions of primary root＂ types of RA decrease. But with shortage of P, the type of lateral roots clustering in the upper and lower regions of primary root increases, and the type of lateral roots clustering in the middle region of primary root decreases, with the types of RA diversified. Under the condition of K deficiency, the type of no lateral root increases and types of lateral roots clustering in the middle region of primary root decrease, and the percentage of such types as ＂no lateral root＂, ＂lateral roots clustering in the upper region of primary root＂, and ＂lateral roots clustering in the upper and middle regions of primary root＂ accounts for 97.9% in all, with the types of RA simplified. With lack of Fe, Mg or Zn, the main type of RA is ＂lateral roots clustering in the upper and middle regions of primary root＂, but the type of lateral roots evenly-distributed on primary root increases. The main type of RA is ＂lateral roots evenlydistributed on primary root＂, under the condition of N deficiency, and the types of RA turn out to be diversified. There exists a close relation between nutrient deficiency and RA changes. Owing to various forms of nutrient deficiency, correspondingly different types of RA hav

关键词： Malus hupehensis (Pamp.) Rehd. paper-culture root architecture (RA) nutrient deficiency

Endoscopy demand among county people in southeast China:A cross-sectional study

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Laparoscopic, Endoscopic and Robotic Surgery 2023年第1期6卷 9-15页

作者： Huihui Yan Zhenghua Lin Shuangjing Gao Chenyu fan mengyue Jiang Liying Que Lanfang Zhou Yingdi Weng Jing Shu Tongyun Zhang Jian Hu Zhiqiang Liu Xi Ye Jianting Cai Guangfa liao Department of Gastroenterology the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China Endoscopy Center of Suichang County People's Hospital Lishui 323300China

Objective The popularization of gastroenteroscopy and the introduction of comfortable medical care have further promoted the growth of people's demand,especially the demand for painless *** cross-sectional study aims to investigate the current situation and change in county people's demand for endoscopy to promote the development of endoscopy centers in county hospitals in southeast *** From October to December 2021,patients and their family members who came to the Gastroenterology Department in Suichang County People's Hospital of Zhejiang Province were randomly selected to complete the questionnaire.A total of 838 valid questionnaires were ***,the original software data of the Endoscopy Center were sampled and retrieved(from October to December every year from 2018 to 2021)for statistical analysis of real-world *** who would choose painless endoscopy the next time in the valid questionnaires were included in the painless endoscopy group,while those who would choose ordinary endoscopy the next time were included in the ordinary endoscopy *** The stepwise forward binary logistic regression model analysis showed that,patients with“secondhand smoke exposure”were more willing to choose painless endoscopy(OR=1.459,95%CI:1.050-2.028,p=0.025).However,patients with an education level of“primary and below”and“junior high school”,and patients who are suffering from“currently experiencing abdominal distension”,were more willing to choose ordinary endoscopy(OR=0.270,95%CI:0.149-0.488,p<0.001;OR=0.528,95%CI:0.330-0.845,p=0.008;OR=0.536,95%CI:0.334-0.861,p=0.010).Patients with previous experience in painless endoscopy tended to choose painless endoscopy the next time,while patients with previous experience in ordinary endoscopy tended to choose ordinary endoscopy the next time(χ^(2)=140.97,p<0.001).From 2018 to 2021,the proportion of painless endoscopy has increased yearly(p<0.001).Most patients indicated that they would“r

关键词： County people Comfortable medical care Painless endoscopy Endoscopic demand Cross-sectional study

Integrated schedule of order picking and delivery for instant delivery

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Journal of Management Science and Engineering 2024年第1期9卷 88-100页

作者： Qiuchen Gu Tijun fan Jingyi Chen School of Business East China University of Science and TechnologyShanghai200237China Research Center for Operations and Supply Chain Management East China University of Science and TechnologyShanghai200237China Economics and Management School Minjiang UniversityFuzhou350108China

In this study,we introduce an integrated schedule of order picking and delivery for instant *** picking,including order batching and picking sequencing,is scheduled online under real-time order arrival,which integrates order delivery by depicting order location dispersion in an online order picking *** delivery,including delivery person assignment and route planning,is modeled to minimize the total duration of order fulfillment by considering the influence of the order picking completion time.A rule-based online order picking strategy is established,and a customized ant colony optimization(ACO)algorithm is proposed to optimize order *** on 16 simulated instances of different scales demonstrate that our online order picking schedule considering order delivery outperforms existing approaches and that the customized ACO algorithm for order delivery is effective.

关键词： Online scheduling Order picking Delivery routing Integrated order picking and delivery Instant delivery