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Acta Mechanica Solida Sinica 2015年第5期28卷 536-555页

作者： Pengzhi Pan Fangsheng Su Haijun Chen Shilin yan Xiating feng Fei yan State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of Sciences School of Science Wuhan University of Technology

The Karhunen-Loeve （KL） expansion and probabilistic collocation method （PCM） are combined and applied to an uncertainty analysis of rock failure behavior by integrating a self- developed numerical method （i.e., the elastic-plastic cellular automaton （EPCA））. The results from the method developed are compared using the Monte Carlo Simulation （MCS） method. It is concluded that the method developed requires fewer collocations than MCS method to obtain very high accuracy and greatly reduces the computational cost. Based on the method, the elasto- plastic and elasto-brittle-plastic analyses of rocks under mechanical loadings are conducted to study the uncertainty in heterogeneous rock failure behaviour.

关键词： uncertainty analysis probabilistic collocation method elasto-plastic cellular au-tomaton Karhunen-Loeve expansion rock failure process PCM-EPCA

Energy-Efficient Cooperative Strategy in RF Energy Harvesting Cognitive Radio Network

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Chinese Journal of Electronics 2019年第3期28卷 651-657页

作者： yan Feiyu zhao Jihong QU Hua XU Xiguang School of Electronic and Information Engineering Xi'an Jiaotong University School of Communication and Information Engineering Xi'an University of Posts and Telecommunications

Energy-efficient cooperative spectrum sharing has become a new trend based on financial and environmental considerations. We focus on a novel energy-efficient cooperative strategy in a Radio frequency(RF) energy harvesting cognitive radio network, where the Secondary user(SU) provides energy supply and relaying assist for the Primary user(PU) in exchange for the transmission opportunities. On the basis of energy and information cooperation, an Energy efficiency(EE)maximization non-convex problem for SU is formulated under the PU’s Quality of service(QoS) requirement and energy-causality constraint. With the aid of Dinkebalch’s method and convex optimization technique, a joint time and power allocation scheme is proposed. Numerical results show that the proposed scheme achieves higher SU’s EE and better PU’s QoS guarantee compared to the scheme in which the SU only provides energy for the PU’s transmission.

关键词： Cognitive radio network Radio frequency(RF) energy harvesting Cooperative communication Energy efficiency Resource management

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铁路职工夜班工作与代谢综合征的关联性分析

现代预防医学 2024年第5期51卷 811-816页

作者：杜懿涵陆崇冯小燕莫枫欣陈青松吴珊广东药科大学公共卫生学院广东药科大学附属第一医院健康管理部广东省公共卫生检测与评价工程技术研究中心

目的探讨夜班工作对铁路工人代谢综合征(metabolic syndrome,MS)的影响。方法选取2021年9—12月在广东药科大学附属第一医院参加职工体检的7 635名铁路职工为研究对象。采用logistic回归进行关联性分析，限制性立方样条(restricted cu... 详细信息

目的探讨夜班工作对铁路工人代谢综合征(metabolic syndrome,MS)的影响。方法选取2021年9—12月在广东药科大学附属第一医院参加职工体检的7 635名铁路职工为研究对象。采用logistic回归进行关联性分析，限制性立方样条(restricted cubic spline,RCS)分析剂量反应关系。结果铁路职工MS患病率为15.1%。调整混杂因素后，曾经夜班工作(OR=1.198, 95%CI:1.002～1.431)、现在夜班工作(OR=1.219, 95%CI:1.048～1.417)、夜班工作6.0～<11.0年(OR=1.323, 95%CI:1.092～1.603)、夜班工作≥11.0年(OR=1.256, 95%CI:1.029～1.534)、每周夜班2次(OR=1.269, 95%CI:1.074～1.498)、每周夜班3次(OR=1.217, 95%CI:1.001～1.479)、每周夜班≥4次(OR=1.295, 95%CI:1.032～1.623)与铁路职工MS患病具有统计学意义。RCS结果显示，夜班工作年限与MS患病风险存在线性的正相关关系(Ptotal<0.001,Pnon-linear=0.076 0),MS的患病风险在夜班1年后开始增加，在夜班达14.1年时风险达到最高。结论夜班工作会导致铁路工人患MS的风险升高，夜班工作年限越高风险越高。

关键词：夜班工作铁路职工代谢综合征剂量反应关系

腹腔镜下子宫肌瘤剔除术与开腹子宫肌瘤切除术治疗效果及术后生育情况对比

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中国计划生育学杂志 2024年第8期32卷 1787-1790页

作者：冯雪曹婧赵恬舒赵晓磊黑龙江省牡丹江市妇幼保健院 157000

目的:分析有生育要求子宫肌瘤患者腹腔镜下子宫肌瘤剔除术与开腹子宫肌瘤切除术的治疗效果。方法:回顾性分析2019年1月-2021年1月在本院行开腹子宫肌瘤切除术(开腹组,n=82)和腹腔镜下子宫肌瘤剔除术(腹腔镜组,n=82)有生育要求子宫肌瘤... 详细信息

目的:分析有生育要求子宫肌瘤患者腹腔镜下子宫肌瘤剔除术与开腹子宫肌瘤切除术的治疗效果。方法:回顾性分析2019年1月-2021年1月在本院行开腹子宫肌瘤切除术(开腹组,n=82)和腹腔镜下子宫肌瘤剔除术(腹腔镜组,n=82)有生育要求子宫肌瘤患者的临床资料。比较两组手术疗效、手术治疗及术后并发症发生率,随访2年术后妊娠情况。结果:开腹组与腹腔镜组手术总有效率(93.0%、100.0%)无差异(P>0.05);腹腔镜组手术时间(72.7±11.5min)、术中出血量(85±16ml)、术后住院(8.7±1.3d)及疼痛消失时间(3.7±0.5d)均低于开腹组(85.1±12.4min、135±32ml、13.0±2.8d、7.8±2.1d),术后并发症总发生率(12.2%)低于开腹组(40.2%)(P0.05);腹腔镜组妊娠后流产(37.8%)及分娩剖宫产率(85.7%)均高于开腹组(16.2%、15.9%)(均P<0.05)。结论:对有生育要求的子宫肌瘤患者,腹腔镜下子宫肌瘤剔除术与开腹子宫肌瘤切除术临床疗效相当,但腹腔镜下子宫肌瘤剔除术围手术指标较好、术后并发症较少,开腹子宫肌瘤切除术术后妊娠结局相对较好。

关键词：子宫肌瘤开腹子宫肌瘤切除术腹腔镜下子宫肌瘤剔除术临床疗效术后妊娠

DRUG AND PLASMID DNA CO-DELIVERY NANOCARRIERS BASED ON ABC-TYPE POLYPEPTIDE HYBRID MIKTOARM STAR COPOLYMERS

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Chinese Journal of Polymer Science 2013年第6期31卷 924-937页

作者： Tao Liu yan-feng Zhang 刘世勇 CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering University of Science and Technology of China

We report on the fabrication of self-assembled micelles from ABC-type miktoarm star polypeptide hybrid copolymers consisting of poly（ethylene oxide）, poly（L-lysine）, and poly（e-caprolactone） arms, PEO（-b-PLL）-b-PCL, and their functional applications as co-delivery nanocarriers of chemotherapeutic drugs and plasmid DNA. Miktoarm star copolymer precursors, PEO（-b-PZLL）-b-PCL, were synthesized at first via the combination of consecutive ＂click＂ reactions and ring-opening polymerizations （ROP）, where PZLL is poly（e-benzyloxycarbonyl-L-lysine）. Subsequently, the deprotection of PZLL arm afforded amphiphilic miktoarm star copolymers, PEO（-b-PLL）-b-PCL. In aqueous media at pH 7.4, PEO（-b-PLL）-b-PCL self-assembles into micelles consisting of PCL cores and hydrophilic PEO/PLL hybrid coronas. The hydrophobic micellar cores can effectively encapsulate model hydrophobic anticancer drug, paclitaxel; whereas positively charged PLL arms within mixed micellar corona are capable of forming electrostatic polyplexes with negatively charged plasmid DNA （pDNA） at N/P ratios higher than ca. 2. Thus, PEO（-b-PLL）-b-PCL micelles can act as co-delivery nanovehicles for both chemotherapeutic drugs and genes. Furthermore, polyplexes of pDNA with paclitaxel-loaded PEO（-b- PLL）-b-PCL micelles exhibited improved transfection efficiency compared to that of pDNA/blank micelles. We expect that the reported strategy of varying chain topologies for the fabrication of co-delivery polymeric nanocarriers can be further applied to integrate with other advantageous functions such as targeting, imaging, and diagnostics.

关键词： Miktoarm star copolymers Gene delivery Co-delivery Polypeptide Self-assembly

Microstructure and Mechanical Properties of a CuCrZr Welding Joint After Continuous Extrusion

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Journal of Materials Science & Technology 2015年第2期31卷 210-216页

作者： Hui feng Haichang Jiang Desheng yan Lijian Rong Institute of Metal Research Chinese Academy of Sciences

The effect of continuous extrusion forming(CEF) process on the microstructure and mechanical properties of a CuCrZr welding joint was investigated. The experimental results showed that after the CEF process the grains were refined to submicron-scale through dynamic recrystallization,which improved the mechanical properties of the welding joint as well as the base material. Meanwhile,the micron-scale precipitates aggregated at the grain boundaries in the welding process were broken down to smaller ones and recrystallized grains of several micrometers formed around the precipitates after CEF process,which could alleviate the negative effect induced by the micron-scale precipitates during plastic deforming process. Finer grains and smaller micronscale precipitates made contributions to improve the properties of a CuCrZr alloy with a welding joint.

关键词： Continuous extrusion Dynamic recrystallization Fla

Chemo-mechanical coupling effect on high temperature oxidation:A review

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Science China(Technological Sciences) 2019年第8期62卷 1297-1321页

作者： FANG XuFei LI yan YUE MengKun feng Xue AML Department of Engineering Mechanics Tsinghua University Beijing 100084 China Center for Mechanics and Materials Tsinghua University Beijing 100084 China Institute of Materials Science Technische Universitat Darmstadt Darmstadt 64287 Germany

The rapid development in the field of chemo-mechanical coupling has drawn increasing attention in recent years. Chemomechanical coupling phenomena exist in many research areas, ranging from development of advanced batteries, biomechanical engineering, hydrogen embrittlement, and high temperature oxidation, etc. In this review, we attempt to provide an overview of the recent advances in chemo-mechanical coupling study on high temperature oxidation. The theoretical frameworks, computational modeling, and experimental studies on this subject are summarized and discussed. The stress-diffusion coupling effect in diffusion-controlled oxidation process, stress-induced evolution of oxide morphology in microscale experiment, and stressoxidation interaction at crack front for intergranular fracture are highlighted. In addition, potential applications and possible methods via surface engineering for improving oxidation-resistance of high temperature structural materials are briefly discussed.

关键词： chemo-mechanical coupling high temperature oxidation microscale experiment fracture

BPSK-QPSK和QPSK-16QAM的光调制格式转换

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太赫兹科学与电子信息学报 2024年第3期22卷 309-315页

作者：林昭王兴财冯世杰电子科技大学电子科学技术研究院四川成都611731

信号在调制方式不同的系统之间传输时,需要对信号调制格式进行转换,而调制格式转换通常在电信号上进行,要将光信号恢复成电信号。在电信号上进行调制格式转换后,再经电光调制器变换成光信号发射。频繁的光电或电光转换通常会增加系统成... 详细信息

信号在调制方式不同的系统之间传输时,需要对信号调制格式进行转换,而调制格式转换通常在电信号上进行,要将光信号恢复成电信号。在电信号上进行调制格式转换后,再经电光调制器变换成光信号发射。频繁的光电或电光转换通常会增加系统成本,针对该问题,提出了利用相干叠加在光域上实现二进制相移键控(BPSK)到正交相移键控(QPSK)以及QPSK到正交幅度调制(16QAM)的调制格式转换的方法。实验通过Optisystem软件对转换模型进行仿真,采用10 Gpbs伪随机信号作为测试信源,通过星座图观测出信号成功转换为QPSK和16QAM;并在不同光信噪比、光源线宽和信号功率下对转换模型与直接QPSK、16QAM传输模型进行误码分析对比,在相同条件下转换模型和直接传输的误码率高度保持一致,表明这种调制格式转换方法具有较高的稳定性和准确性,能够适用于不同系统间的信号传输。

关键词：光通信调制二进制相移键控正交相移键控正交幅度调制

Characterization of fine organic particulate matter from Chinese cooking

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Journal of Environmental Sciences 2004年第4期16卷 570-575页

作者： HELing-yan HUMin WANGLi HUANGXiao-feng ZHANGYuan-hang StateKeyJointLaboratoryofEnvironmentalSimulationandPollutionControl DepartmentofEnvironmentalSciencesCollegeofEnvironmentalSciencesPekingUniversityBeijing100871China BeijingMunicipalInstituteofLaborProtection Beijing100054China

PM 2.5 samples were collected by a three-stage cascade impactor at two kinds of Chinese restaurants to characterize fine organic particulate matter from Chinese cooking sources. Major individual organic compounds have been quantified by GC/MS, including series of alkanes, n-alkanoic acids, n-alkanals, alkan-2-ones and PAHs. Alkanes and ketones make up a significant fraction of particle-phase organic compounds, ranging from C 11 to C 26, and C 9 to C 19, respectively. In addition, other organic compound classes have been identified, such as alkanols, esters, furans, lactones, amides, and nitriles. The mass concentrations of fine particles, alkanes, n-alkanoic acids and PAHs in air emitted from the Uigur style cooking are hundreds times higher than ambient PM 2.5in Beijing.

关键词： Chinese cooking source fine organic particles GC/MS

Prediction of Hyperuricemia Risk Based on Medical Examination Report Analysis

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Journal of Systems Science and Systems Engineering 2020年第4期29卷 468-503页

作者： Rong Hou Yongbo Xiao yan Zhu Hongyan zhao Research Center for Contemporary Management School of Economics and ManagementTsinghua UniversityBeijing 100084China Institute of Industry Internet Tsinghua UniversityBeijing 100084China

This study hopes to contribute to disease detection by analyzing a medical examination dataset with 123,968 *** on association rules mining and related medical knowledge,6 models were constructed here to predict hyperuricemia prevalence and investigated its risk *** different models,the prediction performances of Lasso logistic regression,traditional logistic regression,and random forest are excellent,and the results can be *** logistic regression model also works well,but it is not ***'s prediction performance is relatively poor,while data dimensionality reduction can significantly improve its *** has the worst performance and its efficiency of processing high-dimensional large dataset is extremely *** risk factors of hyperuricemia mainly belongs to 4 categories,which are obesity-related factors,renal function factors,liver function factors,and myeloproliferative diseases-related *** forest,Lasso regression,and logistic regression all treat serum creatinine,BMI,triglyceride,fatty liver,and age as key predictive *** also show that serum urea,serum alanine aminotransferase,negative urobilinogen,red blood cell count,white blood cell count and the pH are significantly correlated with the risk.

关键词： Medical examination hyperuricemia machine learning risk prediction risk factors