检索结果-南通市图书馆

Reinforcement Learning-Based Dynamic Order Recommendation for On-Demand Food Delivery

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2024年第2期29卷 356-367页

作者： xing Wang Ling Wang Chenxin Dong Hao Ren Ke xing Department of Automation Tsinghua UniversityBeijing 100080China School of Mechanical and Automotive Engineering Qingdao Hengxing University of Science and TechnologyQingdao 266100China Meituan Beijing 100015China

On-demand food delivery(OFD)is gaining more and more popularity in modern *** a kernel order assignment manner in OFD scenario,order recommendation directly influences the delivery efficiency of the platform and the delivery experience of *** paper addresses the dynamism of the order recommendation problem and proposes a reinforcement learning solution *** actor-critic network based on long short term memory(LSTM)unit is designed to deal with the order-grabbing conflict between different ***,three rider sequencing rules are accordingly proposed to match different time steps of the LSTM unit with different *** test the performance of the proposed method,extensive experiments are conducted based on real data from Meituan delivery *** results demonstrate that the proposed reinforcement learning based order recommendation method can significantly increase the number of grabbed orders and reduce the number of order-grabbing conflicts,resulting in better delivery efficiency and experience for the platform and riders.

关键词： on-demand food delivery order recommendation reinforcement learning actor-critic network long short term memory

Clinical analysis of secondary penile cancer:a case series at a tertiary referral center in China

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2024年第2期26卷 225-226页

作者： Xiao-yu Li Chun-Ru Xu xing Ji Zhen-Peng Zhu Zhen-Ke Guo Tian-yu Cai Jian Lin Department of Urology Peking University First HospitalBeijing 100034China Institute of Urology Peking UniversityBeijing 100034China National Urological Cancer Center Beijing 100034China Beijing Key Laboratory of Urogenital Diseases(Male)Molecular Diagnosis and Treatment Center Beijing 100034China

Dear Editor,Secondary penile cancer is an extremely rare condition that refers to the metastasis of other malignancies to the *** are limited reports on secondary penile cancer in Asian populations,and perceptions about this disease are extremely *** reviewed and analyzed the data of patients diagnosed with secondary penile cancer based on the pathological findings at Peking University First Hospital in Beijing,China,aiming to expand the clinical reference for this rare disease.

关键词： cancer rare finding

Preoperative neutrophil-to-lymphocyte ratio predicts symptomatic anastomotic leakage in elderly colon cancer patients: Multicenter propensity score-matched analysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Surgery 2024年第2期16卷 438-450页

作者： Chao-Yang Wang Xiao-long Li Xiao-long Ma Xiong-Fei Yang Yong-Yong Liu Yong-Jiang yu Department of Clinical Medicine The First Clinical Medical College of Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Department of Gastrointestinal Surgery First Hospital of Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Department of Clinical Medicine Gansu University of Chinese MedicineLanzhou 730000Gansu ProvinceChina Department of Anorectology Gansu Provincial People’s HospitalLanzhou 730000Gansu ProvinceChina Department of General Surgery The Second Hospital Affiliated to Lanzhou UniversityLanzhou 730000Gansu ProvinceChina

BACKGROUND The neutrophil-to-lymphocyte ratio(NLR),a composite inflammatory biomarker,is associated with the prognosis in patients with colorectal ***,whether the NLR can be used as a predictor of symptomatic postoperative ana-stomotic leakage(AL)in elderly patients with colon cancer is *** To assess the role of the NLR in predicting the occurrence of symptomatic AL after surgery in elderly patients with colon *** Data from elderly colon cancer patients who underwent elective radical colectomy with anastomosis at three centers between 2018 and 2022 were retrospectively *** operating characteristic curve analysis was performed to determine the best predictive cutoff value for the ***-two covariates were matched using a 1:1 propensity score matching method,and univariate and multivariate logistic regression analyses were used to determine risk factors for the development of postoperative *** Of the 577 patients included,36(6.2%)had symptomatic *** optimal cutoff value of the NLR for predicting AL was *** propensity score matching,the incidence of AL was significantly greater in the≥2.66 NLR subgroup than in the<2.66 NLR subgroup(11.5%vs 2.5%;P=0.012).Univariate logistic regression analysis revealed statistically significant correlations between blood transfusion intraoperatively and within 2 d postoper-atively,preoperative albumin concentration,preoperative prognostic nutritional index,and preoperative NLR and AL occurrence(P<0.05);multivariate logistic regression analysis revealed that an NLR≥2.66[odds ratio(OR)=5.51;95%confidence interval(CI):1.50-20.26;P=0.010]and blood transfusion intraoperatively and within 2 d postoperatively(OR=2.52;95%CI:0.88-7.25;P=0.049)were risk factors for the occurrence of symptomatic *** A preoperative NLR≥2.66 and blood transfusion intraoperatively and within 2 d postoperatively are associated with a higher incidence of postoperative symptomatic AL in elderly

关键词： Colon cancer Anastomotic leak Neutrophil-to-lymphocyte ratio Propensity score-matched

Surficial modification enabling planar Al growth toward dendrite-free metal anodes for rechargeable aluminum batteries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第4期67卷 1341-1351页

作者： Wenhao Liu yu Li Bo long Haoyi Yang Lumin Zheng Ying Bai Feng Wu Chuan Wu School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Yangtze Delta Region Academy of Beijing Institute of Technology Jiaxing 314019China

Al metal possesses ultrahigh theoretical volumetric capacity of 8,040 m Ah cm^(-3),and gravimetric capacity of 2,980 m Ah g^(-1),and thus is highly attractive for electrochemical energy ***,it suffers from several issues,such as the dendrite formation,during Al stripping-deposition cycling,which has been verified to account for the short circuit and limited cyclic ***,we use a facile and applicable method to in-situ reconstruct the Al anode surface with F-Al-O chemical bonds,which could preferentially induce the planar growth of Al along the interface plane,thus leading to the dendrite-free morphology evolution during the *** from F-Al-O chemical bonds on the surface of Al anodes,long lifespan of symmetric cells can be realized even under 1 m A cm^(-2)and 1 m Ah cm^(-2).Coupling the F-Al anode with graphite-based cathodes,high-voltage dual-ion Al metal batteries can be achieved with long-term cycle stability up to 1,200 cycles(at 0.5 m A cm^(-2)),surpassing the counterparts using pristine Al metal ***,the effectiveness of this surficial modification strategy is also elucidated with the aid of theoretical *** work provides novel insights on low-cost and facile strategies against the Al dendrite growth in aluminum batteries.

关键词： rechargeable aluminum batteries Al metal anode Al dendrite dual-ion batteries surficial modification

Impact of open hepatectomy on postoperative bile leakage in patients with biliary tract cancer

维普期刊数据库

同方期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Surgery 2024年第1期16卷 67-75页

作者： Gang Wu Wen-Ying Li yu-xing Gong Feng Lin Chen Sun General Surgery Department The Second Affiliated Hospital of Harbin Medical UniversityHarbin 150000Heilongjiang ProvinceChina

BACKGROUND Bile leakage is a common and serious complication of open hepatectomy for the treatment of biliary tract *** To evaluate the incidence,risk factors,and management of bile leakage after open hepatectomy in patients with biliary tract *** We retrospectively analyzed 120 patients who underwent open hepatectomy for biliary tract cancer from February 2018 to February *** leak was defined as bile drainage from the surgical site or drain or the presence of a biloma on *** incidence,severity,timing,location,and treatment of the bile leaks were *** risk factors for bile leakage were analyzed using univariate and multivariate logistic regression *** The incidence of bile leak was 16.7%(20/120),and most cases were grade A(75%,15/20)according to the International Study Group of Liver Surgery *** median time of onset was 5 d(range,1-14 d),and the median duration was 7 d(range,2-28 d).The most common location of bile leakage was the cut surface of the liver(70%,14/20),followed by the anastomosis site(25%,5/20)and the cystic duct stump(5%,1/20).Most bile leaks were treated conservatively with drainage,antibiotics,and nutritional support(85%,17/20),whereas some required endoscopic retrograde cholangiopancreatography with stenting(10%,2/20)or percutaneous transhepatic cholangiography with drainage(5%,1/20).Risk factors for bile leakage include male sex,hepatocellular carcinoma,major hepatectomy,blood loss,and blood *** Bile leakage is a frequent complication of open hepatectomy for biliary tract ***,most cases are mild and can be conservatively *** sex,hepatocellular carcinoma,major hepatectomy,blood loss,and blood transfusion were associated with an increased risk of bile leak.

关键词： Open hepatectomy Bile leak Biliary tract cancer Risk factors Management Complication

Anchoring Ru clusters to highly defective N-doped carbon nanotubes via a thermal-shock strategy for stable industrial hydrogen evolution

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第6期17卷 5261-5269页

作者： Zhiming Li Xinyu Li Haiqing Ma Chenliang Ye Hongan yu long Nie Meng Zheng Jin Wang College of Materials Science and Engineering Shenzhen UniversityShenzhen 518060China School of Chemistry and Materials Science Anhui Normal UniversityWuhu 241002China Department of Power Engineering North China Electric Power UniversityBaoding 071003China

Non-Pt or low-Pt catalysts capable for stable generation of hydrogen via water electrolysis at an industrial level of current density are highly *** of strong metal-support connection is beneficial to improve the performance stability of *** we employed highly defective N-doped carbon nanotubes(d-N-CNT)as the support to achieve uniform and firm anchoring of Ru clusters(~1.9 nm)via a thermal-shock *** as-prepared Ru/d-N-CNT catalyst shows excellent catalytic activity for hydrogen evolution reaction(HER)in alkaline media and requires an overpotential(ƞ)of 12 mV at 10 mA·cm^(−2)and 116 mV at 200 mA·cm^(−2)with a Ru loading of 0.025 mg·cm^(−2).Impressively,Ru/d-N-CNT presents robust stability for HER at both low current density(stable for at least 1000 h at 10 mA·cm^(−2))and the industrial level of current density(stable for at least 100 h at 1000 mA·cm^(−2)),remarkably outperforming commercial Pt/C and Ru/*** highly defective nature of the N-CNT support endowed the as-prepared Ru/d-N-CNT catalyst with strong metal-support adhesion that efficiently suppressed agglomeration as well as obscission of Ru ***,the rich defects increased the surface energy of the N-CNT support and resulted in improved hydrophilicity as evidenced by the liquid contact angle measurement and the bubble evolution process,which also played an important role in stabilizing the HER performance especially at large current density.

关键词： thermal-shock method hydrogen evolution reaction large-current-density Ru cluster

Effects of conductive agent type on lithium extraction from salt lake brine with LiFePO_(4) electrodes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 678-687页

作者： Zhen Zhang Pan Luo Yan Zhang yuhan Wang Li Liao Bo yu Mingshan Wang Junchen Chen Bingshu Guo xing Li School of New Energy and Materials Southwest Petroleum UniversityChengdu 610500China Energy Storage Research Institute Southwest Petroleum UniversityChengdu 610500China

Electrochemical lithium extraction from salt lakes is an effective strategy for obtaining lithium at a low ***,the elevated Mg:Li ratio and the presence of numerous coexisting ions in salt lake brines give rise to challenges,such as prolonged lithium extraction periods,diminished lithium extraction efficiency,and considerable environmental *** this work,Li FePO4(LFP)served as the electrode material for electrochemical lithium *** conductive network in the LFP electrode was optimized by adjusting the type of conductive *** approach resulted in high lithium extraction efficiency and extended cycle *** the single conductive agent of acetylene black(AB)or multiwalled carbon nanotubes(MWCNTs)was replaced with the mixed conductive agent of AB/MWCNTs,the average diffusion coefficient of Li+in the electrode increased from 2.35×10^(-9)or 1.77×10^(-9)to 4.21×10^(-9)cm^(2)·s^(-1).At the current density of 20 mA·g^(-1),the average lithium extraction capacity per gram of LFP electrode increased from 30.36 mg with the single conductive agent(AB)to 35.62 mg with the mixed conductive agent(AB/MWCNTs).When the mixed conductive agent was used,the capacity retention of the electrode after 30 cycles reached 82.9%,which was considerably higher than the capacity retention of 65.8%obtained when the single AB was ***,the electrode with mixed conductive agent of AB/MWCNTs provided good cycling *** the conductive agent content decreased or the loading capacity increased,the electrode containing the mixed conductive agent continued to show excellent electrochemical ***,a self-designed,highly efficient,continuous lithium extraction device was *** electrode utilizing the AB/MWCNT mixed conductive agent maintained excellent adsorption capacity and cycling performance in this *** work provides a new perspective for the electrochemical extraction of lithium using LFP electrodes.

关键词： salt lake brine lithium extraction electrochemical lithium extraction conductive agent extraction efficiency adsorption capacity

Unraveling magnetic properties and martensitic transformation in Mn-rich Ni-Mn-Sn alloys:first-principles calculations and experiments

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第4期43卷 1769-1785页

作者： yu Zhang Jing Bai Ke-Liang Guo Jia-Xin Xu Jiang-long Gu Nicola Morley Qui-Zhi Gao yu-Dong Zhang Claude Esling Xiang Zhao Liang Zuo Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Material Science and EngineeringNortheastern UniversityShenyang110819China Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province School of Resources and MaterialsNortheastern University at QinhuangdaoQinhuangdao066004China Department of Material Science and Engineering University of SheffieldSheffieldS13JDUK State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004China Laboratoire d’Étude des Microstructures Et de Mécanique des Matériaux University of Lorraine57045MetzFrance

We have investigated the phase stability,magnetic properties,and martensitic transformation thermodynamics/kinetics of the Ni_(24-x)Mn_(18+x+y)Sn_(6-y)(x,y=0,1,2)system by combining the first-principles calculations and *** calculation results show that the optimized lattice parameters are consistent with the experimental ***,we obtain the relation equation for the austenite formation energy(E_(form-A))and Mn content(X_(Mn)):E_(form-A)=507.358X_(Mn)-274.126,as well as for the six-layer modulated(6M)martensite formation energy(E_(form-6M))and Ni content(X_(Ni)):E_(form-6M)=-728.484X_(Ni)+*** ternary phase diagram of the total magnetic moment was *** excess Mn will reduce the total magnetic moment of 6M(Mag6M)and non-modulated(NM)(MagNM)martensites,with the following equations relating the total magnetic moment and Mn content:Mag_(6M)=-15.905X_(Mn)+7.902and Mag_(NM)=-14.781X_(Mn)+7.411,while the effect on austenite is *** variation of total magnetic moment is mainly dominated by the Mn atomic magnetic *** 3d electrons of Mn_(Sn)(Mn at Sn sublattice)play an important role in magnetic properties from the perspective of the electronic density of *** on the thermodynamics of martensitic transformation,the alloys will likely undergo austenite?6M?NM transformation *** the thermodynamic and kinetic results,the martensitic transformation temperature decreases with x increasing and increases with y *** results are expected to provide reference for predicting the phase stability and magnetic properties of NiMn-Sn alloys.

关键词： Ni-Mn-Sn First-principles calculations Martensitic transformation Magnetic property Kinetics

Nitrogen-doped carbon dots as photocatalysts for organic synthesis:Effect of nitrogen content on catalytic activity

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第6期17卷 4825-4833页

作者： Kai-Kai Niu Chao-Qun Ma Rui-Zhi Dong Hui Liu Sheng-Sheng yu Ling-Bao xing School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China

Regulating the doping of carbon dots(CDs)and the generation of reactive oxygen species(ROS)is essential to selectively control their application in photocatalytic organic *** study successfully synthesized five newly developed nitrogen-doped carbon dots(CDs 1-5)with varying nitrogen content,which have the ability to generate ROS when exposed to light radiation,specifically superoxide anion radicals(O_(2)•-)and singlet oxygen(^(1)O_(2)).The utilization of the aforementioned nitrogen-doped CDs as photocatalysts enables the realization of their potential in facilitating efficient photocatalytic organic ***,it was observed that the photocatalytic efficiency exhibited a gradual decrease when the nitrogen content in the CDs *** order to provide more evidence for this claim,we employed a set of five CDs in the context of photocatalytic dehalogenation ofα-bromoacetophenone,photocatalytic oxidative coupling reaction of amines to imines,photooxidation reaction of sulfides to sulfoxides,and cross-dehydrogenation coupling(CDC)reaction,in which it was further observed that there was a steady decrease in the yields of photocatalytic organic reactions as the nitrogen content in CDs ***,CDs 1 exhibited the best photocatalytic efficiency,thereby reinforcing the hypothesis that a higher nitrogen content corresponds to a decreased catalytic *** study not only investigates the impact of the nitrogen content on the catalytic performance of CDs,but also offers valuable insights for the future utilization of CDs for photocatalytic organic reactions in water.

关键词： carbon dots nitrogen-doped reactive oxygen species photocatalysis