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Graph neural network-based scheduling for multi-UAV-enabled communications in D2D networks

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Digital Communications and Networks 2024年第1期10卷 45-52页

作者： pei li lingyi Wang Wei Wu Fuhui Zhou Baoyun Wang Qihui Wu Nanjing University of Posts and Telecommunications Nanjing210023China Nanjing University of Aeronautics and Astronautics Nanjing210016China

In this paper,we jointly design the power control and position dispatch for Multi-Unmanned Aerial Vehicle(UAV)-enabled communication in Device-to-Device(D2D)*** objective is to maximize the total transmission rate of Downlink Users(DUs).Meanwhile,the Quality of Service(QoS)of all D2D users must be *** comprehensively considered the interference among D2D communications and downlink *** original problem is strongly non-convex,which requires high computational complexity for traditional optimization *** to make matters worse,the results are not necessarily globally *** this paper,we propose a novel Graph Neural Networks(GNN)based approach that can map the considered system into a specific graph structure and achieve the optimal solution in a low complexity ***,we first construct a GNN-based model for the proposed network,in which the transmission links and interference links are formulated as vertexes and edges,***,by taking the channel state information and the coordinates of ground users as the inputs,as well as the location of UAVs and the transmission power of all transmitters as outputs,we obtain the mapping from inputs to outputs through training the parameters of *** results verified that the way to maximize the total transmission rate of DUs can be extracted effectively via the training on ***,it also shows that the performance of proposed GNN-based method is better than that of traditional means.

关键词： Unmanned aerial vehicle D2 Dcommunication Graph neural network Power control Position planning

Phosphotungstic acid immobilized on amino-functionalized TS-1 zeolite as a solid acid catalyst for the synthesis of tributyl citrate

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Chinese Journal of Chemical Engineering 2024年第6期70卷 199-210页

作者： pei li Bianfang Shi Junyao Shen Ran Cui Wenze Guo ling Zhao Zhenhao Xi State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

The amino-functionalization of TS-1 zeolite followed by immobilization of phosphotungstic acid(HPW)was presented to prepare a strong solid acid catalyst for the synthesis of bio-based tributyl citrate from the esterification of citric acid and n-butanol.γ-Aminopropyltriethoxysilane(APTES)was first grafted on the TS-1 zeolite via the condensation reactions with surface hydroxyl groups,and subsequently the HPW was immobilized via the reaction between the amino groups and the protons from HPW-forming strong ionic *** Keggin structure of HPW and MFI topology of TS-1 zeolite were well maintained after the *** amino-functionalization generated abundant uniformly distributed active sites on TS-1 for HPW immobilization,which promoted the dispersity,abundance,as well as the stability of the acid *** tetrahedrally coordinated framework titanium and non-framework titania behaved as weak Lewis acid sites,and the protons from the immobilized HPW acted as the moderate or strong Brønsted acid *** optimized TBC yield of 96.2%(mol)with a conversion of-COOH of 98.1%(mol)was achieved at 150℃for 6 h over the HPW immobilized on amino-functionalized *** catalyst exhibited good stability after four consecutive reaction runs,where the activity leveled off at still a relatively high level after somewhat deactivation possibly caused by the leaching of a small portion of weakly anchored APTES or HPW.

关键词： Amino-functionalization Phosphotungstic acid TS-1 zeolite Esterification Tributyl citrate

Construction of a predictive model for acute liver failure after hepatectomy based on neutrophil-to-lymphocyte ratio and albuminbilirubin score

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1087-1096页

作者： Xiao-pei li Zeng-Tao Bao li Wang Chun-Yan Zhang Wen Yang Department of Family Planning and Assisted Reproductive Technology The First People’s Hospital of LianyungangLianyungang 222000Jiangsu ProvinceChina Department of Gastrointestinal Surgery The First People’s Hospital of LianyungangLianyungang 222000Jiangsu ProvinceChina Department of Laboratory Medicine The First People’s Hospital of LianyungangLianyungang 222000Jiangsu ProvinceChina Department of Gynecology The First People’s Hospital of LianyungangLianyungang 222000Jiangsu ProvinceChina

BACKGROUND Acute liver failure(ALF)is a common cause of postoperative death in patients with hepatocellular carcinoma(HCC)and is a serious threat to patient *** neutrophil-to-lymphocyte ratio(NLR)is a common inflammatory indicator that is associated with the prognosis of various diseases,and the albumin-bilirubin score(ALBI)is used to evaluate liver function in liver cancer ***,this study aimed to construct a predictive model for postoperative ALF in HCC tumor integrity resection(R0)based on the NLR and ALBI,providing a basis for clinicians to choose appropriate treatment *** To construct an ALF prediction model after R0 surgery for HCC based on NLR and *** In total,194 patients with HCC who visited The First People’s Hospital of lianyungang to receive R0 between May 2018 and May 2023 were enrolled and divided into the ALF and non-ALF *** compared differences in the NLR and ALBI between the two *** risk factors of ALF after R0 surgery for HCC were screened in the univariate *** risk factors were analyzed by multifactorial logistic *** then constructed a prediction model of ALF after R0 surgery for HCC.A receiver operating characteristic curve,calibration curve,and decision curve analysis(DCA)were used to evaluate the value of the prediction *** Among 194 patients with HCC who met the standard inclusion criteria,46 cases of ALF occurred after R0(23.71%).There were significant differences in the NLR and ALBI between the two groups(P<0.05).The univariate analysis showed that alpha-fetoprotein(AFP)and blood loss volume(BLV)were significantly higher in the ALF group compared with the non-ALF group(P<0.05).The multifactorial analysis showed that NLR,ALBI,AFP,and BLV were independent risk factors for ALF after R0 surgery in *** predictive efficacy of NLR,ALBI,AFP,and BLV in predicting the occurrence of ALT after R0 surgery for HCC was average[area under the curve(AUC)NLR=0.767,AUCALB

关键词： Acute liver failure Hepatocellular carcinoma Hepatectomy Neutrophil-to-lymphocyte ratio Albumin-bilirubin score

The meta-analyses on effectiveness and safety of colorectal cancer screening

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Chinese Medical Journal 2024年第12期137卷 1471-1473页

作者： pei li Xueyang Zeng Zuoxiang liu Jichun Yang Yueying li Le Gao Hongmei Zeng lin Zhang Feng Sun Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing 100191China Peking Union Medical College Beijing 100005China Centre for Safe Medication Practice and Research Department of Pharmacology and PharmacyLi Ka Shing Faculty of MedicineThe University of Hong KongHong KongChina Department of Cancer Registry National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China School of Population Medicine and Public Health Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China

To the Editor:The colorectal cancer(CRC)is the fourthmost common cause of cancer deaths in China that was treated as a public health threat,accounting for approximately 10%of all the cancer-caused mortalities each year.[1]It usually takes decades to develop from a polyp to full CRC,[2]which allows a time window for detecting precancerous lesions and taking early steps for preventions and treatments.

关键词： colorectal prevention cancer

Evaluation of the injection and plugging ability of a novel epoxy resin in cement cracks

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Petroleum Science 2024年第2期21卷 1211-1220页

作者： Guang-Yao Leng Wei Yan Hai-Mu Ye Er-Dong Yao Ji-Bin Duan Zheng-Xian Xu Ke-pei li Jing-Ru Zhang Zhong li State Key Laboratory of Petroleum Resource&Prospecting China University of Petroleum(Beijing)Beijing102249China CNPC liaohe Oilfield Gas Storage Co.LTD Panjin124000LiaoningChina CNOOC Research Institute Co. Ltd.Beijing100028China

Sustained casing pressure(SCP)is a crucial issue in the oil and gas production *** resins,exhibiting exceptional compressive strength,ductility,and shear bonding strength,have the potential to form reliable *** injectivity and sealing capacity of the epoxy resin is crucial parameters for the success of shallow remediation *** study aimed to develop and assess a novel solid-free resin sealant as an alternative to Portland cement for mitigating fluid *** investigation evaluated the viscosity,compressive strength,and brittleness index of the epoxy resin sealant,as well as its tangential and normal shear strengths in conjunction with casing *** flow characteristics and sealing abilities of conventional cement and epoxy resin were comparatively analyzed in *** results showed that the application of a viscosity reducer facilitated control over the curing time of the epoxy resin,ranging from 1.5 to 6 h,and reduced the initial viscosity from 865.53 to 118.71 m Pa,*** mechanical properties of the epoxy resin initially increased with a rise in curing agent content before experiencing a minor *** epoxy resin containing 30%curing agent exhibited optimal mechanical *** a 14-day curing period,the epoxy resin's compressive strength reached81.37 MPa,2.12 times higher than that of cement,whereas the elastic modulus of cement was 2.99 times greater than that of the epoxy *** brittleness index of epoxy resin is only 3.42,demonstrating high flexibility and *** tangential and normal shear strengths of the epoxy resin exceeded those of cement by 3.17 and 2.82 times,*** a 0.5 mm-wide crack,the injection pressure of the epoxy resin remained below 0.075 MPa,indicating superior injection and flow ***,the injection pressure of cement surged dramatically to 2.61 MPa within 5 *** breakthrough pressure of0.5 PV epoxy resin reached 7.53 MPa,decreasing the crack's perme

关键词： Sustained casing pressure Epoxy resin sealant Curing agent Viscosity reducer Mechanical properties Crack sealing

基于元网络的电动汽车高速公路充电设施选址优化方法

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中国公路学报 2024年第4期37卷 1-13页

作者：李佳佩谢驰同济大学道路与交通工程教育部重点实验室上海201804 同济大学交通运输工程学院上海201804 同济大学城市交通研究院上海201804

针对高速公路网中电动汽车充电基础设施选址优化问题,从由充电节点间子路径构成的元网络出发,构建了一个两阶段混合整数线性规划模型,并相应地设计了一种两阶段优化算法。第1阶段,在原始节点-路段网络中找到每对充电节点间的距离约束最... 详细信息

针对高速公路网中电动汽车充电基础设施选址优化问题,从由充电节点间子路径构成的元网络出发,构建了一个两阶段混合整数线性规划模型,并相应地设计了一种两阶段优化算法。第1阶段,在原始节点-路段网络中找到每对充电节点间的距离约束最小成本子路径,通过双目标标号修正算法来求解,其结果用以构建充电节点-子路径元网络;第2阶段,在元网络中应用分支定界算法,其核心计算步骤是找到每个起讫对之间的最小成本路径,可通过经典的单目标标号设定算法求解;最后将提出的基于元网络的分支定界算法应用于长江三角洲高速公路网。结果表明:充电站建设成本限制和电动汽车续航里程限制是决定充电站选址决策和出行者路径-充电决策的重要因素;其与传统基于原始网络的分支定界算法在3种不同规模网络算例中的应用性能比较表明,对于求解较大规模的基础设施选址优化问题,基于元网络的分支定界算法表现出压倒性的计算效率优势。

关键词：交通工程选址优化问题元网络充电基础设施电动汽车

Synthesis of Branched Polyethylene via Bulky α-Diimine Nickel(II)-Catalyzed Ethylene Chain-Walking Polymerization

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Open Journal of Organic Polymer Materials 2024年第1期13卷 1-12页

作者： Zhengquan Dong pei li Guoyong Xu Fuzhou Wang Institutes of Physical Science and Information Technology School of Computer Science and Technology Anhui University Hefei China

The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, which contains both dibenzhydryl and phenyl groups, was determined by X-ray crystallography. The compound has a pseudo-tetrahedral geometry at the Ni center, showing pseudo-C2-symmetry. Upon activation with modified methylaluminoxane (MMAO), Ni1 exhibits high catalytic activity up to 1.02 × 107 g PE (mol Ni h)−1 toward ethylene polymerization, enabling the synthesis of high molecular weight branched polyethylene. The molecular weights and branching densities could be tuned over a very wide range. The polymerization results indicated the possibility of precise microstructure control, depending on the polymerization temperature. The branching densities were decreased with increasing the polymerization temperature.

关键词： Ethylene Polymerization α-Diimine Ni(II) Complex Chain-Walking Polymerization Branched Polyethylene

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人体感染狒狒巴拉姆希阿米巴脑炎1例报告

中国人兽共患病学报 2024年第7期40卷 696-700页

作者：李道佩广东省中山市小榄人民医院(中山市第五人民医院) 中山528415

目的探讨狒狒巴拉姆希阿米巴脑炎的临床特点、诊断方法和治疗策略。方法回顾性分析病例资料。结果患者入院时检查异常的指标有:呼吸道病原体IgM阳性,华大基因测序结果检出狒狒巴拉姆希阿米巴的检出序列数为55,脑脊液分析结果显示白细胞... 详细信息

目的探讨狒狒巴拉姆希阿米巴脑炎的临床特点、诊断方法和治疗策略。方法回顾性分析病例资料。结果患者入院时检查异常的指标有:呼吸道病原体IgM阳性,华大基因测序结果检出狒狒巴拉姆希阿米巴的检出序列数为55,脑脊液分析结果显示白细胞计数为371×10^(6)/L,蛋白定量为3321.4 mg/L,葡萄糖为2.33 mmol/L,氯化物为110 mmol/L,这些数据表明,患者存在严重感染症和免疫紊乱。经过6 d治疗,患者的病情虽有所好转,仍然危重。由于缺乏特效药物,预后极差,家属要求出院。结论狒狒巴拉姆希阿米巴脑炎是一种罕见但危险的疾病,临床表现多样,诊断难度较大,缺乏特效药物,治疗难度极大,预后极差。但对于疑似狒狒巴拉姆希阿米巴脑炎的患者,乃应早期进行综合性治疗,包括抗感染、免疫调节等治疗措施。

关键词：狒狒巴拉姆阿米巴脑炎基因测序脑脊液低蛋白血症低钾血症高钠血症

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基于机器学习算法的服装直播销量预测模型

丝绸 2024年第7期61卷 109-117页

作者：韩铂李沛上海工程技术大学纺织服装学院上海201620

为了完善直播销量预测的指标体系,提高直播销量预测的准确率,本文对比多种机器学习算法,分析服装直播销量的影响因素并预测服装直播销量。首先,通过文献分析选取直播销量的影响因素,并使用Spearman相关系数结合显著性进行筛选。其次,通... 详细信息

为了完善直播销量预测的指标体系,提高直播销量预测的准确率,本文对比多种机器学习算法,分析服装直播销量的影响因素并预测服装直播销量。首先,通过文献分析选取直播销量的影响因素,并使用Spearman相关系数结合显著性进行筛选。其次,通过不同机器学习算法建立服装销量预测模型。选用R 2、MAE、RMSE及MAPE为评价指标,采用5折交叉验证的方法,测试各模型性能。研究结果表明:主播粉丝数、主播近30天场均观看人次、主播近30天场均坑产、产品价格、产品讲解时长、产品近30天历史销量、品牌粉丝数、品牌近30天历史销量、折扣这9个因素之间共线性较弱且与直播销量之间的相关性显著,可作为预测模型中的影响因素;预测算法中K近邻算法和随机森林算法的表现较好,R 2均大于0.98,MAPE均在30.5%以内。预测结果可帮助零售商规划库存,调整生产计划,为产品采购、定价、推广提供数据支持。

关键词：直播销量预测机器学习随机森林 K近邻 SVM支持向量机五折交叉验证