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Acta Mathematicae Applicatae Sinica 2018年第3期34卷 553-565页

作者： shi-jie wang Chuan-wei ZHANG Xue-jun wang Wen-sheng wang School of Mathematic Sciences Anhui University Hefei 230601 China School of Economics Hangzhou Dianzi University Hangzhou 310018 China

Consider a discrete-time risk model with insurance and financial risks in a stochastic economic environment. Assume that the insurance and financial risks form a sequence of independent and identically distributed random vectors with a generic random vector following a wide type of dependence structure. An asymptotic formula for the finite-time ruin probability with subexponential insurance risks is derived. In doing so, the subexponentiality of the product of two dependent random variables is investigated simultaneously.

关键词： discrete-time risk model finite-time ruin probability subexponentiality product dependence structure

Quaternion-Based Adaptive Trajectory Tracking Control of a Rotor-Missile with Unknown Parameters Identification

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Defence Technology（防务技术） 2024年第1期31卷 375-386页

作者： jie Zhao Zhongjiao shi Yuchen wang Wei wang Beijing Institute of Technology Beijing 100081China

This paper investigates the adaptive trajectory tracking control problem and the unknown parameter identification problem of a class of rotor-missiles with parametric system ***,considering the uncertainty of structural and aerodynamic parameters,the six-degree-of-freedom(6Do F) nonlinear equations describing the position and attitude dynamics of the rotor-missile are established,respectively,in the inertial and body-fixed reference ***,a hierarchical adaptive trajectory tracking controller that can guarantee closed-loop stability is proposed according to the cascade characteristics of the 6Do F ***,a memory-augmented update rule of unknown parameters is proposed by integrating all historical data of the regression *** long as the finitely excited condition is satisfied,the precise identification of unknown parameters can be ***,the validity of the proposed trajectory tracking controller and the parameter identification method is proved through Lyapunov stability theory and numerical simulations.

关键词： Rotor-missile Adaptive control Parameter identification Quaternion control

Survival after repeat hepatectomy for recurrent colorectal liver metastasis: A review and meta-analysis of prognostic factors

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Hepatobiliary & Pancreatic Diseases International 2019年第4期18卷 313-320页

作者： shi-jie wang Xiao-Ying Si Zhi-Bin Cai Yan-Ming Zhou Department of Hepatobiliary and Pancreatovascular Surgery First Affiliated Hospital of Xiamen University

Background:Frequent recurrent hepatic metastasis after hepatic metastasectomy is a major obstacle in the treatment of colorectal liver metastasis(CRLM).We performed the present systematic review to evaluate the short-and long-term outcomes after repeat hepatectomy for recurrent CRLM and determine factors associated with survival in these *** sources:An electronic search of PubMed database was undertaken to identify all relevant peerreviewed papers published in English between January 20 0 0 and July *** ratios(HR)with 95%confidence interval(95%CI)were calculated for prognostic factors of overall survival(OS).Results:The search yielded 34 studies comprising 3039 patients,with a median overall morbidity of 23%(range 8%–71%),mortality of 0(range 0–6%),and 5-year OS of 42%(range 17%–73%).Pooled analysis showed that primary T3/T4 stage tumor(HR=1.94;95%CI:1.04–3.63),multiple tumors(HR=1.49;95%CI:1.10–2.01),largest liver lesion≥5 cm(HR=1.89;95%CI:1.11–3.23)and positive surgical margin(HR=1.80;95%CI:1.09–2.97)at initial hepatectomy,and high serum level of carcinoembryonic antigen(HR=1.87;95%CI:1.27–2.74),disease-free interval≤12 months(HR=1.34;95%CI:1.10–1.62),multiple tumors(HR=1.64;95%CI:1.32–2.02),largest liver lesion≥5 cm(HR=1.85;95%CI:1.34–2.56),positive surgical margin(HR=2.25;95%CI:1.39–3.65),presence of bilobar disease(HR=1.62;95%CI:1.19–2.20),and extrahepatic metastases(HR=1.60;95%CI:1.23–2.09)at repeat hepatectomy were significantly associated with poor OS.

关键词： Colorectal cancer Metastasectomy Prognosis Meta-analysis

Long-term outcomes of combined hepatocellular-cholangiocarcinoma after hepatectomy or liver transplantation: A systematic review and meta-analysis

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Hepatobiliary & Pancreatic Diseases International 2019年第1期18卷 12-18页

作者： De-Bang Li Xiao-Ying Si shi-jie wang Yan-Ming Zhou Department Ⅲ of General Surgery the First Hospital of Lanzhou University Department of Hepatobiliary & Pancreatovascular Surgery First Affiliated Hospital of Xiamen University

Background: Combined hepatocellular-cholangiocarcinoma(cHCC-CC) is a rare primary liver malignancy. We conducted a systematic review and meta-analysis to assess the evidence available on the long-term outcomes of cHCC-CC patients after either hepatectomy or liver transplantation(LT). Data Sources: Relevant studies published between January 2000 and January 2018 were identified by searching Pub Med and Embase and reviewed systematically. Data were pooled using a random-effects model. Results: A total of 42 observational studies involving 1691 patients(1390 for partial hepatectomy and 301 for LT) were included in the analysis. The median tumor recurrence and 5-year overall survival(OS) rates were 65%(range 38%–100%) and 29%(range 0–63%) after hepatectomy versus 54%(range 14%–93%) and 41%(range 16%–73%) after LT, respectively. Meta-analysis found no significant difference in OS and tumor recurrence between LT and hepatectomy groups. Conclusion: Hepatectomy rather than LT should be considered as the prior treatment option for cHCC-CC.

关键词： Combined hepatocellular-cholangiocarcinoma Liver transplantation Hepatectomy Treatment Prognosis

Proposal of a new T-stage classification system for ampullary carcinoma based on Surveillance,Epidemiology and End Result(SEER)database

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Hepatobiliary & Pancreatic Diseases International 2021年第6期20卷 568-573页

作者： shi-jie wang Yi-Fei Li Shan Liao You-Zhu Wei Yan-Ming Zhou Department of Hepatobiliary and Pancreatovascular Surgery First Affiliated Hospital of Xiamen UniversityXiamen 361003China

Background:Tumor size is still considered a useful prognostic factor in currently available tumor-nodemetastasis(TNM)classification staging systems for most solid tumors,but the significance of tumor size on the prognosis of ampullary carcinoma remains *** aim of the current study was to propose a new T-stage classification system for ampullary carcinoma to address the impact of tumor size on the prognostic ***:Using the Surveillance,Epidemiology,and End Results(SEER)database,we identified 1080 patients with ampullary carcinoma who underwent radical surgical resection between 2004 and *** on the results obtained from analysis of various clinicopathologic factors,a new T-stage classification system was ***:Among the 1080 patients,618 were men and 462 were women,with a median tumor size of 2.3(range 0.1–12)*** the 7 th edition of the American Joint Committee on Cancer(AJCC)staging manual,we noticed significant differences in overall survival(OS)between T2 vs.T3 tumors(P<0.001)and T3 vs.T4 tumors(P=0.002),but failed to observe significant differences between T1 vs.T2 tumors(P=0.498)in our pair-wise *** the newly developed T-stage classification system,we were able to differentiate significant differences in OS between T1 vs.T2 tumors(P=0.032),T2 vs.T3 tumors(P<0.001)and T3 vs.T4 tumor(P=0.003)in all pair-wise *** c-index of the new staging system was 0.653(95%CI:0.629–0.677),showing a better discriminatory power than the 0.636 of the 7 th AJCC staging system(95%CI:0.612–0.660).Conclusions:The new T-stage classification system described herein can better differentiate prognostic outcomes after radical resection in patients with ampullary carcinoma by incorporating tumor size and depth of tumor infiltration.

关键词： Ampullary carcinoma Cancer staging SEER

Investigation on crystallization behavior between(Sc_(x)Yb_(1−x))O_(1.5)and CMAS:A new insight in the effect of Sc substitution

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Journal of Advanced Ceramics 2024年第6期13卷 789-799页

作者： Guangheng Zhang Jinyu shi jie Zhang Jingyang wang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

Environmental barrier coatings(EBCs)with thermomechanical robustness against calcium–magnesium–aluminum–silicate(CMAS)deposits are in high *** aim of this work was to clarify the influence of Sc^(3+)on the crystallization behavior of Yb-based coatings against CMAS *** reaction products of solid solutions with compositions traversing the Sc_(2)O_(3)–Yb_(2)O_(3)system indicate that Sc^(3+)tends to form[BO_(6)]coordination polyhedra in the crystal structure to promote the formation of garnet and diopside,while Yb^(3+)occupies 7-,8-,and 9-coordinate sites to crystallize apatite and *** transformation of crystalline products from apatite/silicocarnotite to garnet/diopside greatly improves the efficiency of CMAS melt consumption and facilitates the prevention of its further penetration and *** on the commonality of cation occupancy in crystallography,an A(CaO+YbO_(1.5))–B(ScO_(1.5)+MgO+AlO_(1.5))–T(SiO_(2))pseudoternary phase diagram is established,which has great potential for describing phase equilibrium in coating-deposit systems and can provide guidance for the compositional design of corrosion-resistant coatings.

关键词： crystallization behavior cation partitioning scandium-ytterbium oxide(Sc_(x)Yb_(1−x))O_(1.5)solid solution calcium-magnesium-aluminum-silicate(CMAS)deposit pseudoternary phase diagram

Zircon U-Pb-Hf isotopic and geochemical characteristics of the Xierzi biotite monzogranite pluton,Linxi,Inner Mongolia and its tectonic implications

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Geoscience Frontiers 2018年第2期9卷 505-516页

作者： Qing-Bin Guan Zheng-Hong Liu Xing-An wang Bin wang shi-jie wang Yu-Song Chen Zhi-Qiang Feng College of Earth Sciences Jilin UniversityChangchun 130061China College of Geographical Sciences Northeast Normal UniversityChangchun 130024China Shandong Provincial No.6 Exploration Institute of Geology and Mineral Resources Weihai 264209China Department of Earth Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

The opening, subduction and final closure of the Paleo-Asian Ocean led to the formation of the Central Asian Orogenic Belt. Controversy has long surrounded the timing of final closure of the Paleo-Asian Ocean. Here we present zircon U-Pb ages and petrological, geochemical and in situ Hf isotope data for the Xierzi biotite monzogranite pluton, Linxi, SE Inner Mongolia. U-Pb dating of zircon by LA-ICP-MS yields a middle Permian emplacement age(268.7 ± 2.3 Ma) for the Xierzi pluton that is dominated by biotite monzogranites with high SiO_2(71.2-72.8 wt.%),alkali(Na_2 O + K_2 O =8.05-8.44 wt.%), Al_2 O_3(14.4-15.2 wt.%) and Fe_2 O_3~T relative to low MgO contents, yielding Fe_2 O_3~T/MgO ratios of 2.87-3.44, and plotting within the high-K calc-alkaline field on a SiO_2 vs. K_2 O diagram. The aluminum saturation indexes(A/CNK) of the biotite monzogranites range from 1.06 to 1.19, corresponding to weakly to strongly peraluminous. They are enriched in rare earth elements(REE), high field strength elements(HFSEs; Zr,Hf). and large ion lithophile elements(LILEs; Rb, U, Th). The LREEs are enriched relative to the HREEs,with a distinct negative Eu anomaly in a chondrite-normalized REE diagram. Geochemically, the Xierzi biotite monzogranite is classified as an aluminous A-type granite, with all samples plotting within the A2-type granite field on a Y/Nb vs. Rb/Nb diagram. Zircon ε_(Hf)(t) values and two-stage modal ages of the zircons within the pluton range from +4.80 to +13.65 and from 983 to 418 Ma, respectively, indicating that the primary magma was generated through partial melting of felsic rocks from juvenile ***, these results demonstrate that the Xierzi pluton formed under the post-orogenic extensional setting after arc-continent collision in the middle Permian.

关键词： Linxi area A-type granite Zircon U-Pb dating Extensional tectonic setting Paleo-Asian Ocean Arc-continent collision

Locally and globally uniform approximations for ruin probabilities of a nonstandard bidimensional risk model with subexponential claims

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 98-113页

作者： LIU Zai-ming GENG Bing-zhen wang shi-jie School of Mathematics and Statistics Central South UniversityChangsha 410083China School of Big Data and Statistics Anhui UniversityHefei 230601China

Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair of the claim-inter-arrival times is arbitrarily *** some mild conditions,we achieve a locally uniform approximation of the finite-time ruin probability for all time horizon within a finite *** we further assume that each pair of the claim-inter-arrival times is negative quadrant dependent and the two classes of claims are consistently-varying-tailed,it shows that the above obtained approximation is also globally uniform for all time horizon within an infinite interval.

关键词： bidimensional risk model asymptotic formula subexponential distribution consistently varying tail ruin probability

Research on intelligent search-and-secure technology in accelerator hazardous areas based on machine vision

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Nuclear Science and Techniques 2024年第4期35卷 96-107页

作者： Ying-Lin Ma Yao wang Hong-Mei shi Hui-jie Zhang School of Traffic and Transportation Beijing Jiaotong UniversityBeijing 100044China School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Prompt radiation emitted during accelerator operation poses a significant health risk,necessitating a thorough search and securing of hazardous areas prior to ***,manual sweep methods are ***,the limitations of manual sweeps have become increasingly evident with the implementation of large-scale *** leveraging advancements in machine vision technology,the automatic identification of stranded personnel in controlled areas through camera imagery presents a viable solution for efficient search and *** the criticality of personal safety for stranded individuals,search and security processes must be sufficiently *** ensure comprehensive coverage,180°camera groups were strategically positioned on both sides of the accelerator tunnel to eliminate blind spots within the monitoring *** YOLOV8 network model was modified to enable the detection of small targets,such as hands and feet,as well as larger targets formed by individuals near the ***,the system incorporates a pedestrian recognition model that detects human body parts,and an information fusion strategy is used to integrate the detected head,hands,and feet with the identified pedestrians as a cohesive *** strategy enhanced the capability of the model to identify pedestrians obstructed by equipment,resulting in a notable improvement in the recall ***,recall rates of 0.915 and 0.82were obtained for Datasets 1 and 2,*** there was a slight decrease in accuracy,it aligned with the intended purpose of the search-and-secure software *** tests conducted within an accelerator tunnel demonstrated the effectiveness of this approach in achieving reliable recognition outcomes.

关键词： Search and secure Machine vision Camera Human body parts recognition Particle accelerator Hazardous area

In situ cosmogenic ^(10)Be, ^(26)Al, and ^(21)Ne dating in sediments from the Guizhou Plateau, southwest China

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Science China Earth Sciences 2021年第8期64卷 1305-1317页

作者： Ye YANG Yu LIU Yan MA Sheng XU Cong-Qiang LIU shi-jie wang Finlay M.STUART Derek FABEL Institute of Surface-Earth System Science School of Earth System ScienceTianjin UniversityTianjin 300072China Scottish Universities Environmental Research Centre East Kilbride G750QFUK State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing 100029China

Landscape evolution is modulated by the regional tectonic uplift,climate change,and river ***,how to distinguish these mechanisms through the research of surface exhumation and fluvial incision remains *** this study,cosmogenic ^(10)Be,^(26)Al,and ^(21)Ne concentrations in quartz from cave deposits,modern river sediments,and bedrocks were measured to constrain the applicability of cosmogenic ^(21)Ne and discuss Quaternary landscape evolution history in the Guizhou Plateau,southeast *** the ^(26)Al-^(10)Be and ^(21)Ne-^(10)Be pairs to distinguish the cosmogenic ^(21)Ne concentration from the excess ^(21)Ne,we found that the nucleogenic ^(21)Ne produced by the U and Th decay in quartz is significant in the samples although there is the possibility of inherited cosmogenic ^(21)*** with previous studies,we suggest that the precise approach for applying the cosmogenic ^(21)Ne could be reached by(1)estimating the contribution from nucleogenic ^(21)Ne,(2)avoiding samples with complex burial histories to exclude inherited cosmogenic ^(21)Ne,and(3)combining the ^(10)Be-^(26)Al-^(21)Ne nuclides method for the Quaternary *** addition,both pre-burial basin denudation rates and burial ages derived from the ^(26)Al-^(10)Be pair were used to determine the different timescale surface denudation rate and fluvial incision rate in relation to previous *** consistency of the different timescales pre-burial basin denudation rate,^(36)Cl surface denudation rate,and modern basin denudation rate indicates that the landscape-scale surface denudation has been likely stabilized since the Quaternary in the Guizhou Plateau *** slightly higher river incision rates than the local surface denudation rate show that the river dynamics may not have reached a steady-state due to the regional tectonic uplift in the Guizhou Plateau.

关键词： Cosmogenic^(10)Be-^(26)Al-^(21)Ne Burial dating Incision rate Landscape evolution Guizhou Plateau