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Endoscopic retrograde cholangiopancreatography for diagnosing and treating pediatric biliary and pancreatic diseases

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World Journal of Gastrointestinal Surgery 2023年第10期15卷 2272-2279页

作者： Xiu-Min Qin Fei-Hong Yu chuan-kai lv Zhi-Min Liu Jie Wu Department of Gastroenterology Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijing 100045China Department of Ultrasound Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijing 100045China Department of Radiology Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijing 100045China

BACKGROUND This study evaluated the safety and effectiveness of endoscopic retrograde cholangiopancreatography(ERCP)in pediatric patients with biliary and pancreatic diseases.A retrospective analysis was conducted on 57 ERCP procedures performed in 41 children,primarily for treating pancreatic *** overall success rate was 91.2%,with no major complications ***-ERCP pancreatitis(PEP)occurred in 8.8%of ***-up examinations over one year showed no recurrence of biliary or pancreatic ***,endoscopic treatment led to a significant increase in body mass index(BMI).These findings demonstrate the valuable role of ERCP in managing such *** To evaluate the safety and efficacy of ERCP for the management of biliary and pancreatic diseases in pediatric *** We conducted a retrospective analysis of data from children aged 1-18 years who underwent ERCP for biliary and pancreatic diseases at Beijing Children’s Hospital between January 2021 and December *** collected data included procedure time,endoscopic treatment,success rate,and postoperative *** Forty-one children underwent 57 ERCP procedures,including 14 with biliary duct disease and 27 with pancreatic *** mean age of the patients was 7.48±3.48 *** duct-related treatments were performed 18 times,and pancreatic disease treatments were performed 39 *** was primarily used to treat pediatric pancreatic diseases[68.4%(39/57)of the procedures].The overall success rate was 91.2%(52/57 patients).PEP was noted in five patients(8.8%,5/57),and no instances of bleeding,perforation,or cholangitis were *** patients were followed up for over one year,and no recurrence of biliary or pancreatic diseases was ***,BMI significantly increased after endoscopic treatment compared to that before treatment(P=0.001).CONCLUSION The high success rate and lack of major complications support the valuable role of ERCP in the

关键词： Pediatric Endoscopic retrograde cholangiopancreatography Choledocholithiasis Chronic pancreatitis Pancreatic ducts Postoperative complications

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A fully nonlinear approach for efficient ship-wave simulation

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Journal of Hydrodynamics 2023年第6期35卷 1027-1040页

作者： kai-yuan Shi Ren-chuan Zhu School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China

This paper presents an efficient time-domain method for simulating nonlinear ship *** proposed method,implemented in an earth-fixed coordinate system,integrates a compact boundary element domain within a high-order spectral layer,enabling accurate modeling of both near-field and far-field ship *** overset mesh method and an attention mechanism are employed to track the moving *** effectiveness of the method is validated through simulations of Wigley and Series 60 ships sailing at various *** numerical results,including the nonlinear wave run-up at the ship bow,surface pressure distribution on the hull,and the ship resistance,agree well with experimental data and published numerical results,confirming that the method is capable of accurately simulating the nonlinear ship waves.

关键词： Fully nonlinear ship wake potential flow spectral coupled method wave-making resistance

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ANALYSIS OF BATCH ARRIVAL QUEUE WITH RANDOMIZED VACATION POLICY AND AN UN-RELIABLE SERVER

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Journal of Systems Science & Complexity 2012年第4期25卷 759-777页

作者： Jau chuan KE kai Bin HUANG Department of Applied Statistics National Taichung University of Science and Technology Department of Engineering Information System Development Ardebtec Corporation Ltd.

This paper examines an M[x]/G/1 queueing system with an unreliable server and a delayed repair, in which the server operates a randomized vacation policy with multiple vacations. Whenever the system is empty, the server immediately takes a,vacation. If there is at least one customer found waiting in the queue upon returning from a vacation, the server will be immediately activated for service. Otherwise, if no customers are waiting for service at the end of a vacation, the server either remains idle with probability p or leaves for another vacation with probability 1 -p. Whenever one or more customers arrive when the server is idle, the server immediately starts providing service for the arrivals. The server may also meet an unpredictable breakdown and the repair may be delayed. For such a system the authors derive the distributions of some important system characteristics, such as the system size distribution at a random epoch and at a departure epoch, the system size distribution at the busy period initiation epoch, and the distribution of the idle period and the busy period. The authors perform a numerical analysis for changes in the system characteristics, along with changes in specific values of the system parameters. A cost effectiveness maximization model is constructed to explain the benefits of such a queueing system.

关键词： Cost effectiveness delayed repair randomized vacation queue reliability.

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Interwrapping Distinct Metal-Organic Frameworks in DualMOFs for the Creation of Unique Composite Catalysts

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Research 2021年第1期2021卷 1213-1224页

作者： Jia-Long Ling kai Chen chuan-De Wu State Key Laboratory of Silicon Materials Department of ChemistryZhejiang UniversityHangzhou 310027China

Incorporating metal nanoparticles(MNPs)inside metal-organic frameworks(MOFs)demonstrates superior catalytic properties in numerous reactions;however,the size and distribution of MNPs could not be well controlled,resulting in low product selectivity in catalysis by undergoing different catalytic reaction *** report herein a facile strategy for integrating lattice-mismatched MOFs together to fabricate homogeneously distributed“dual-MOFs,”which are the ideal precursors for the preparation of MNPs@MOFs with unique catalytic *** a proof of concept,we successfully synthesize a dual-MOF HKUST-1/ZIF-8 for in situ creation of redox-active Cu NPs inside hierarchical porous ZIF-8 under controlled pyrolytic *** the advantages of size-tunable Cu NPs in the molecular sieving matrix of ZIF-8,Cu@ZIF-8 demonstrates high activity and selectivity for transformation of alkynes into alkenes without overhydrogenation,which surpasses most of the catalysts in the ***,this work paves a new pathway for developing highly efficient and selective heterogeneous catalysts to produce highly value-added chemicals.

关键词： properties. selectivity proof

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Instance-Specific Algorithm Selection via Multi-Output Learning

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Tsinghua Science and Technology 2017年第2期22卷 210-217页

作者： kai Chen Yong Dou Qi lv Zhengfa Liang the National Laboratory for Parallel and Distributed Processing National University of Defense TechnologyChangsha 410037China the College of Computer National University of Defense TechnologyChangsha 410037China

Instance-specific algorithm selection technologies have been successfully used in many research fields,such as constraint satisfaction and planning. Researchers have been increasingly trying to model the potential relations between different candidate algorithms for the algorithm selection. In this study, we propose an instancespecific algorithm selection method based on multi-output learning, which can manage these relations more *** kinds of multi-output learning methods are used to predict the performances of the candidate algorithms：（1）multi-output regressor stacking;（2） multi-output extremely randomized trees; and（3） hybrid single-output and multioutput trees. The experimental results obtained using 11 SAT datasets and 5 Max SAT datasets indicate that our proposed methods can obtain a better performance over the state-of-the-art algorithm selection methods.

关键词： algorithm selection multi-output learning extremely randomized trees performance prediction constraint satisfaction

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Divergent synthesis of chiral amines via Ni-catalyzed chemo-and enantioselective hydrogenation of alkynone imines

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Science China Chemistry 2023年第11期66卷 3186-3192页

作者： Yuchuan Ma kai Liu Lin He Hui lv Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan School of Chemistry and Chemical EngineeringShihezi UniversityShihezi 832000China Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationSauvage Center for Molecular SciencesKey Laboratory of Biomedical Polymers of Ministry of Education&College of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China

Ligand-mediated nickel-catalyzed asymmetric hydrogenation of alkynone imines has been achieved. By using Ni(OAc)_2·4H_2O/(S,S)-Ph-BPE complex as a catalyst, the chemo-and enantioselective hydrogenation of alkynone imines occurred efficiently to afford chiral propargyl amines with high yields and excellent enantioselectivities(up to 99% yield, >99% ee), leaving the readily reducible alkynyl group intact. Both the C=N and C≡C bonds of alkynone imines were hydrogenated efficiently in the presence of Ni(OAc)_2·4H_2O and Josiphos SL-J011-1, furnishing unfunctionalized chiral imines efficiently(up to 99% yield, >99% ee).The(Z)-allylamines and(E)-allylamines were also efficiently prepared from alkynone imines by the combination of the different catalytic systems. The preliminary mechanism study revealed that the reduction of alkynone imines was a stepwise process and the C=N bonds were preferably hydrogenated in the complete reduction of alkynone imines. The synthetic utility of this method was demonstrated by its application in the late-stage modification of the antiviral drug Zidovudine and the concise synthesis of chiral dibenzoazepine.

关键词： alkynone imine asymmetric hydrogenation propargyl amine enantioselectivity chiral amine

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RANDOMIZED POLICY OF A POISSON INPUT QUEUE WITH J VACATIONS

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Journal of Systems Science and Systems Engineering 2010年第1期19卷 50-71页

作者： Jau-chuan KE kai-Bin HUANG Wen Lea PEARN Department of Applied Statistic National Taichung lnstitute of Technology Taichung 404 Taiwan China Department of Industrial and Engineering Management National Chiao Tutig University Hsing Chu 300 Taiwan China

This paper studies the operating characteristics of an M/G/1 queuing system with a randomized control policy and at most J vacations. After all the customers are served in the queue exhaustively, the server immediately takes at most J vacations repeatedly until at least N customers are waiting for service in the queue upon returning from a vacation. If the number of arrivals does not reach N by the end of the jth vacation, the server remains idle in the system until the number of arrivals in the queue reaches N. If the number of customers in the queue is exactly accumulated N since the server remains idle or returns from vacation, the server is activated for services with probability p and deactivated with probability （l-p）. For such variant vacation model, other important system characteristics are derived, such as the expected number of customers, the expected length of the busy and idle period, and etc. Following the construction of the expected cost function per unit time, an efficient and fast procedure is developed for searching the joint optimum thresholds （N＊,J＊） that minimize the cost function. Some numerical examples are also presented.

关键词： Cost 〈 p N 〉 -policy supplementary variable technique vacation

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A synergetic strategy based on laser surface texturing and lubricating grease for improving the tribological and electrical properties of Ag coating under current-carrying friction

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Friction 2021年第5期9卷 978-989页

作者： Zhengfeng CAO Yanqiu XIA chuan CHEN kai ZHENG Yi ZHANG School of Advanced Manufacturing Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing 102206China Global Energy Interconnection Research Institute Co. Ltd.Beijing 102211China

Herein,a series of Ag coatings with different micro‐dimples were fabricated on copper surfaces by laser surface texturing(LST)and magnetron *** graphene lubricating grease(MGLG)was prepared using multilayer graphene as an *** textured Ag coatings and MGLG were ***,the tribological and electrical performances of the textured Ag coatings under MGLG lubrication were investigated in *** demonstrated that the textured Ag coating with an appropriate dimple diameter could exhibit improved tribological and electrical properties when compared to the non‐textured Ag coating under MGLG *** characterization and analysis of the worn surfaces suggest that the synergetic effect of LST and MGLG contributes to these excellent tribological and electrical properties.

关键词： laser surface texturing tribology contact resistance lubricating grease

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Numerical Simulation and Analysis of Migration Law of Gas Mixture Using Carbon Dioxide as Cushion Gas in Underground Gas Storage Reservoir

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Journal of Harbin Institute of Technology(New Series) 2014年第3期21卷 121-128页

作者： chuan-kai Niu Yu-Fei Tan School of Municipal & Environment Engineering Harbin Institute of Technology

One of the major technical challenges in using carbon dioxide( CO2) as part of the cushion gas of the underground gas storage reservoir( UGSR) is the mixture of CO2and natural gas. To decrease the mixing extent and manage the migration of the mixed zone,an understanding of the mechanism of CO2and natural gas mixing and the diffusion of the mixed gas in aquifer is necessary. In this paper,a numerical model based on the three dimensional gas-water two-phase flow theory and gas diffusion theory is developed to understand this mechanism. This model is validated by the actual operational data in Dazhangtuo UGSR in Tianjin City,*** the validated model,the mixed characteristic of CO2and natural gas and the migration mechanism of the mixed zone in an underground porous reservoir is further studied. Particularly,the impacts of the following factors on the migration mechanism are studied: the ratio of CO2injection,the reservoir porosity and the initial operating pressure. Based on the results,the optimal CO2injection ratio and an optimal control strategy to manage the migration of the mixed zone are obtained. These results provide technical guides for using CO2as cushion gas for UGSR in real projects.

关键词： underground gas storage reservoir(UGSR) cushion gas carbon dioxide mixed zone porous media

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Distribution of P2O5 between solid solution and liquid phase in dephosphorization slag of CaO-SiO2-FeO-P2O5-Na2O system

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Journal of Iron and Steel Research International 2019年第11期26卷 1162-1170页

作者： chuan-ming Du Ning-ning lv Chang Su Wei-ming Liu Jin-xing Yang Hai-chuan Wang Institute of Multidisciplinary Research for Advanced Materials Tohoku UniversitySendaiMiyagi 980-8577Japan School of Metallurgical Engineering Anhui University of TechnologyMa'anshan 243032AnhuiChina Key Laboratory of Metallurgical Emission Reduction and Resources Recycling(Anhui University of Technology) Ministry of Education.Ma'anshan 243002Anhui.China

A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot *** dephosphorization,the generated slag with high P2O5 content is regarded as a P *** P2O5 was mainly concentrated in the 2CaO SiO2-3CaO P2O5 solid solution,the recovery of P from dephosphorization slag primarily depends on the separation of the solid solution from other *** distribution ratios of P2O5 between solid solution and liquid phase in the CaOSiO2-FeO-P2O5-Nslag system were *** results indicated that the addition of Na2O facilitated the enrichment of P2O5 in the solid solution because it increased not only the distribution ratio of P2O5 but also the mass fraction of the solid *** distribution ratio of P2O5 was independent of the P2O5 content in slag.A higher P2O5 content in slag resulted in higher P2O5 and Na2O contents in the solid *** distribution ratio of P2O5 increased with the total Fe content in the liquid phase,regardless of the valence of *** increase in the FeO content in slag brought a higher P2O5 content in the solid *** slag basicity increased,the distribution ratio of P2O5 increased,but the P2O5 content in the solid solution decreased.

关键词： Dephosphorization Steelmaking slag Distribution ratio P2O5 2CaO·SiO2-3CaO·P2O5 solid solution

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