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Comparative assessment and analysis of Rortex vortex in swirling jets

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Journal of Hydrodynamics 2019年第3期31卷 495-503页

作者： Nan Gui Liang Ge peng-xin cheng xing-tuan Yang Ji-yuan Tu Sheng-yao Jiang Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua University Beijing 100084 China School of Engineering RMIT University Melbourne VIC 3083 Australia

Recently, a new definition, called Rortex, was proposed to quantify the purely rotational motion of fluids. In this work, based on the DNS data, the Rortex is used to assess and visualize the rotational motion and structure of the vortex in swirling jets in comparison with other kinds of vortex criteria, including Q , λ2,vorticity and Ω criteria. The Rortex vector,Ω, Q and criteria are found to be better than the vorticity criterion for the vortex core identification. The vector triangle formed by the Rortex R , the nonrotational shear S , and the vorticity R is analyzed to give mechanical explanations, especially of the effect of the non-rotational shear on the rotation of fluids. In addition, the probability density distributions (PDF) of the Rortex R , the nonrotational shear S, and the vorticity R are computed. The peak value of the PDF of the vorticity could be used to explain the pure rigid rotation effect and the combination effects of the rigid rotation and the non?rotational shear.

关键词： Swirling flow vortex Rortex direct numerical simulation rigid rotation non-rotational shear

Analysis and correlation of fluid acceleration with vorticity and Liutex(Rortex)in swirling jets

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Journal of Hydrodynamics 2019年第5期31卷 864-872页

作者： Nan Gui Hou-bo Qi Liang Ge peng-xin cheng Hao Wu xing-tuan Yang Ji-yuan Tu Sheng-yao Jiang Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy TechnologyKey Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing100084China School of Engineering RMIT UniversityMelbourneAustralia

The characteristics of the acceleration a and its correlation with the vortex core in the swirling flow are analyzed in this paper.The swirling flows of four swirl numbers(Sn=n S 0,0.10,0.20 and 0.36)are simulated by the direct numerical simulation,and the fluid mass particles from the inlet of the swirling flow are traced as a database for the current study.The correlations of the acceleration a with the vortex identification parameters of R andωare quantified,where R is the parameter of the“Liutex”-method proposed by Prof.Liu,and its early version is“Rortex”.The probability density functions of the included angles of a-R and a-ωare computed,which are used to clarify the geometrical configuration between a and R.The covariance coefficients between a and the parameters of various vortex core criteria(Q,λ2,ΩL,ΩR,ωand R)are computed and their relative levels of correlation are compared.Compared to the velocity,the expectation and the rms of the acceleration magnitudes and its projections on R and the plane perpendicular to R are computed for better explaining the correlation features between a and R.It is found that a and R are always either perpendicular or parallel to each other with the quantized included angles of∠(a,R)=kπ/2,(k=0,1,2).This confirms the role of R which works as the axis of the vortex exclusively.

关键词： swirling flow acceleration correlation vortex Rortex Liutex direct numerical simulation

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“材料选择与设计”课程中案例教学创新实践

教育教学论坛 2024年第3期 129-132页

作者：彭成信杨光智上海理工大学材料与化学学院上海200093

“材料选择与设计”课程旨在使学生利用材料选择和设计的基本原则,通过实际工程案例学习,掌握工程应用中材料合理选择与设计的能力。然而,在实际教学过程中,它存在理论与实践相脱节、实践教学条件有限等问题,影响了教学效果。建立一套... 详细信息

“材料选择与设计”课程旨在使学生利用材料选择和设计的基本原则,通过实际工程案例学习,掌握工程应用中材料合理选择与设计的能力。然而,在实际教学过程中,它存在理论与实践相脱节、实践教学条件有限等问题,影响了教学效果。建立一套科学有序、教学实效性强的案例库,并不断丰富教学手段,改进案例教学中理论与实践相结合的教学方法,以提高案例教学中学生的参与度,以期为社会培养扎实理论功底和实践操作能力兼具的应用创新型人才,为材料领域应用型创新型人才培养提供借鉴。

关键词：材料选择与设计案例教学网络教学平台教学改革

Spacelike Framed Curves with Lightlike Components and Singularities of Their Evolutes and Focal Surfaces in Minkowski 3-space

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1521-1532页

作者： peng cheng LI Dong He PEI xin ZHAO School of Mathematics and Statistics Northeast Normal UniversityChangchun 130024P.R.China Department of Mathematics Harbin Institute of TechnologyWeihai 264209P.R.China School of Mathematics and Statistics Qingdao UniversityQingdao 266071P.R.China

In this paper,we define the evolute and focal surface of a spacelike framed curve with lightlike components in Minkowski 3-space.It is a generalization of the previous results of regular spacelike curves,since singularities are allowed in the original spacelike curves studied by spacelike framed curves with lightlike components.Meanwhile,we show a new geometric invariant to characterise singularities of the focal surface.Then,the classification theorem and recognition theorem for the singularities of the focal surface in generic are also given.

关键词： Evolutes focal surfaces spacelike framed curves singularities

Metochalcone induces senescence-associated secretory phenotype via JAK2/STAT3 pathway in breast cancer

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Oncology Research 2024年第5期32卷 943-953页

作者： JIANBO ZHOU FENG WAN BIN XIAO xin LI cheng peng FU peng Department of Pharmacology West China School of PharmacySichuan UniversityChengduChina State Key Laboratory of Southwestern Chinese Medicine Resources Chengdu University of Traditional Chinese MedicineChengduChina Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial TechnologySichuan UniversityChengduChina chengdu No.1 Pharmaceutical Co. Ltd.PengzhouChina chengdu Push Bio-Technology Co. Ltd.ChengduChina

Breast and lung cancers are the leading causes of mortality and most frequently diagnosed cancers in women and men,respectively,worldwide.Although the antitumor activity of chalcones has been extensively studied,the molecular mechanisms of isoliquiritigenin analog 2',4',4-trihydroxychalcone(metochalcone;TEC)against carcinomas remain less well understood.In this study,we found that TEC inhibited cell proliferation of breast cancer BT549 cells and lung cancer A549 cells in a concentration-dependent manner.TEC induced cell cycle arrest in the S-phase,cell migration inhibition in vitro,and reduced tumor growth in vivo.Moreover,transcriptomic analysis revealed that TEC modulated the activity of the JAK2/STAT3 and P53 pathways.TEC triggered the senescence-associated secretory phenotype(SASP)by repressing the JAK2/STAT3 axis.The mechanism of metochalcone against breast cancer depended on the induction of SASP via deactivation of the JAK2/STAT3 pathway,highlighting the potential of chalcone in senescence-inducing therapy against carcinomas.

关键词： Metochalcone Breast cancer Lung cancer SASP JAK2/STAT3

Modeling of LF refining process:a review

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Journal of Iron and Steel Research(International) 2024年第2期31卷 289-317页

作者： Zi-cheng xin Jiang-shan Zhang Kai-xiang peng Jun-guo Zhang Chun-hui Zhang Qing Liu State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing100083China Tangshan Branch Hebei Iron and Steel Co.Ltd.Tangshan063000HebeiChina xinjiang Bayi Iron and Steel Co. Ltd.Baosteel GroupWulumuqi830022XinjiangChina

With the increasing demand for energy conservation and emission reduction,more attentions have been paid to the intelligentization,greenization and low carbonization during the transformation and upgrading of steelmaking plants.Ladle furnace(LF)refining is one of the key procedures in steelmaking process and has been widely used in steelmaking plants for its high equipment matching degree,low equipment investment and outstanding refining performance.According to the main tasks of LF refining process,the modeling methods of temperature prediction model,slag-making model,alloying model,argon blowing model and model of inclusions behavior were systematically reviewed,and the advantages and disadvantages of each modeling method were summarized.In addition,the technical framework for the future has also been proposed based on existing works,including classification of raw materials,graphic representation of knowledge,introduction,upgradation and management of device/equipment,customization of steelmaking,modeling of refining process,synergy of models,intelligentization of decision-making,automation of control,and digitization of processes and operations,aiming to provide a reference for the modeling and intelligent development of LF refining process.

关键词： LF refining Temperature prediction Slag-making Alloying Argon blowing Inclusion behavior Modeling method

Prognostic prediction model of colorectal cancer based on preoperative serum tumor markers

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1344-1353页

作者： Yu-Hang Diao Si-Qi Rao xin-peng Shu Yong cheng Can Tan Li-Juan Wang Dong peng Department of Gastrointestinal Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China

BACKGROUND Preoperative serum tumor markers not only play a role in the auxiliary diagnosis and postoperative monitoring in colorectal cancer(CRC),but also have been found to have potential prognostic value.AIM To analyze whether preoperative serum tumor markers,including carcinoembryonic antigen(CEA)and carbohydrate antigen 19-9(CA19-9),affect the prognosis of CRC.METHODS This was a retrospective study conducted in a single center.Patients with nonmetastatic CRC who underwent initial surgery between January 2011 and January 2020 were enrolled and divided into development site and validation site groups at a ratio of 7:3.The independent prognostic factors were screened by Cox regression analysis,and finally,a prognostic nomogram model was established.The newly developed model was tested by internal validation.RESULTS Eventually,3526 postoperative patients with nonmetastatic CRC were included in the study.There were 2473 patients at the development site and 1056 patients at the validation site.Age(P<0.01,HR=1.042,95%CI=1.033-1.051),tumor node metastasis(TNM)classification(P<0.01,HR=1.938,95%CI=1.665-2.255),preoperative CEA(P=0.001,HR=1.393,95%CI=1.137-1.707)and CA19-9(P<0.01,HR=1.948,95%CI=1.614-2.438)levels were considered independent prognostic factors for patients with nonmetastatic CRC and were used as variables in the nomogram model.The areas under the curve of the development and validation sites were 0.655 and 0.658,respectively.The calibration plot also showed the significant performance of the newly established nomogram.CONCLUSION We successfully constructed a nomogram model based on age,TNM stage,preoperative CEA,and CA19-9 levels to evaluate the overall survival of patients with nonmetastatic CRC.

关键词： Colorectal cancer Prognosis Carcinoembryonic antigen Carbohydrate antigen 19-9 Nomogram

Rapid Phase Ambiguity Elimination Methods for DOA Estimator via Hybrid Massive MIMO Receive Array

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Chinese Journal of Electronics 2024年第1期33卷 175-184页

作者： Xichao ZHAN Zhongwen SUN Feng SHU Yiwen CHEN xin cheng Yuanyuan WU Qi ZHANG Yifan LI peng ZHANG School of Information and Communication Engineering Hainan University School of Electronic and Optical Engineering Nanjing University of Science and Technology

For a sub-connected hybrid multiple-input multiple-output(MIMO) receiver with K subarrays and N antennas, there exists a challenging problem of how to rapidly remove phase ambiguity in only single time-slot. A direction of arrival(DOA) estimator of maximizing received power(Max-RP) is proposed to find the maximum value of K-subarray output powers, where each subarray is in charge of one sector, and the center angle of the sector corresponding to the maximum output is the estimated true DOA. To make an enhancement on precision, Max-RP plus quadratic interpolation(Max-RP-QI) method is designed. In the proposed Max-RP-QI, a quadratic interpolation scheme is adopted to interpolate the three DOA values corresponding to the largest three receive powers of Max-RP.To achieve the Cramer Rao lower bound, a Root-MUSIC plus Max-RP-QI scheme is developed. Simulation results show that the proposed three methods eliminate the phase ambiguity during one time-slot and also show low computational complexities. The proposed Root-MUSIC plus Max-RP-QI scheme can reach the Cramer Rao lower bound,and the proposed Max-RP and Max-RP-QI are still some performance losses 2–4 d B compared to the Cramer Rao lower bound.

关键词： Hybrid analog and digital Direction of arrival Massive hybrid multiple-input multiple-output Phase ambiguity Low computational complexity

Clinical analysis of multiple primary gastrointestinal malignant tumors:A 10-year case review of a single-center

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1204-1212页

作者： cheng-Lou Zhu Ling-Zhi peng The First School of Clinical Medicine Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Department of Surgical Oncology Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina

BACKGROUND Multiple primary malignant tumors(MPMTs)was first described by Billroth as early as 1889,with the first report published by Warren and Gates in 1932.Since then,numerous cases have been reported.A literature review of 1104269 patients with cancer revealed that the incidence of MPMTs ranged from 0.73 to 11.7%.In recent years,however,there has been a significant upward trend in the incidence of this phenomenon,which may be associated with many different factors,including the advancement of modern diagnostic procedures facilitating the examination and diagnosis of more MPMTs,increased exposure to chemotherapy and radiotherapy that exacerbate the risk of new malignant tumors in patients with cancer,and prolonged survival of patients with cancer allowing sufficient time for the development of new primary cancers.AIM To analyze the incidence,clinical features,treatment factors,prevalence,and prognosis of patients with MPMTs in the gastrointestinal tract treated in a single center.Additionally,we analyzed the different tumor combinations,time interval between the occurrence of tumors,and staging.METHODS This retrospective cohort study analyzed 8059 patients with pathologically confirmed gastrointestinal malignant tumors treated at the Gansu Province Hospital in Lanzhou,Gansu,China between June 2011 and June 2020.Of these,85 patients had MPMTs.The clinical features,treatment factors,prevalence,and prognosis of this latter cohort were analyzed.RESULTS The incidence of MPMTs in patients with gastrointestinal malignant tumors was 1.05%(85/8059),including 83 double primary malignant tumors and two triple primary malignant tumors of which 57(67.06%)were synchronous MPMTs(SMPMTs)and 28(32.94%)were metachronous MPMTs(MMPMTs).The most frequent associations were found between the rectum colon cancers within the SMPMT category and the gastric-colon cancers within the MMPMT category.For the MMPMTs,the median interval was 53 months.The overall 1-,3-and 5-year survival rates from diagnosis of the first primary cancer were 9

关键词： Multiple primary malignant tumors Clinical characteristics Gastrointestinal tract Prognosis Epidemiology