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Development of powerful algorithm for maximal eigenpair

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Frontiers of Mathematics in China 2019年第3期14卷 493-519页

作者： Mu-Fa CHEN yue-shuang LI School of Mathematical Sciences Beijing Normal University Laboratory of Mathematics and Complex Systems (Beijing Normal University) Ministry of Education Beijing 100875 China

Based on a series of recent papers, a powerful algorithm is reformulated for computing the maximal eigenpair of self-adjoint complex tridiagonal matrices. In parallel, the same problem in a particular case for computing the sub-maximal eigenpair is also introduced. The key ideas for each critical improvement are explained. To illustrate the present algorithm and compare it with the related algorithms, more than 10 examples are included.

关键词： Powerful algorithm maximal eigenpair sub-maximal eigenpair Hermitizable tridiagonal matrix

Can executive mobility reduce the stock price crash risk?Evidence from China

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Economic and Political Studies 2023年第4期11卷 529-540页

作者： Jing Zhang shuang yue shuang Zi School of Finance Shandong University of Finance and EconomicsJi’nanChina

The 21st century has witnessed increasing fluctuations in boththe real economy and financial markets around the world. Howto maintain the stability of the capital market has attracted moreserious attention. This paper examines the impact of executivemobility on the stock price crash risk at the company level. Basedon the data of A-share listed companies during 2010–2019, ourempirical results show that executive mobility can effectivelyreduce the stock price crash risk. Furthermore, our research confirms that employee salaries play an intermediary role in theimpact of executive mobility on the stock price crash risk. Thispaper has important implications for companies in emerging markets to optimise the structure of their executive teams.

关键词： Executive mobility stock price crash risk employee salaries

Celiomesenteric trunk: New classification based on multidetector computed tomography angiographic findings and probable embryological mechanisms

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World Journal of Clinical Cases 2019年第23期7卷 3980-3989页

作者： Wei Tang Jing Shi Lian-Qin Kuang shuang-yue Tang Yi Wang Department of Radiology Daping HospitalArmy Medical UniversityChongqing 400042China Sichuan Key Laboratory of Medical Imaging Department of RadiologyAffiliated Hospital of North Sichuan Medical CollegeNanchong 637000Sichuan ProvinceChina Department of Nursing Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072Sichuan ProvinceChina

BACKGROUND In previous studies,celiomesenteric trunk(CMT)was narrowly defined as a hepato-gastro-spleno-mesenteric(HGSM)trunk,but other possible types were *** the widespread use of multidetector computed tomography(MDCT)angiography,it is easy to collect a large sampling of data on arterial anatomy of the abdomen in daily radiological practice.A new classification system for CMT may be created based on its MDCT angiographic findings and variation *** To identify the spectrum and prevalence of CMT according to a new classification based on MDCT angiographic findings,and discuss the probable embryological mechanisms to explain the CMT *** A retrospective study was carried out on 5580 abdominal MDCT angiography *** was defined as a single common trunk arising from the aorta and its branches including the superior mesenteric artery and at least two major branches of the celiac *** types of CMT were *** Of the 5580 patients,171(3.06%)were identified as having *** to the new definitions and classification,the CMT variants included five types:Ⅰ,Ⅱ,Ⅲ,Ⅳ and Ⅴ,which were found in 96(56.14%),57(33.33%),4(2.34%),3(1.75%)and 8(4.68%)patients,*** CMT variants also were classified as long type(106 patients,61.99%)and short type(65 patients,38.01%)based on the length of single common *** CMT classification was based on the origin of the left gastric artery:Type a(92 patients,53.80%),type b(57 patients,33.33%),type c(11 patients,6.43%)and type d(8 patients,4.68%).CONCLUSION We systematically classified CMT variants according to our new classification system based on MDCT angiographic *** interruption,incomplete interruption and persistence of the longitudinal anastomosis could all be embryological mechanisms of various types of CMT variants.

关键词： Celiac artery Mesenteric artery superior Anatomic variation Classification Computed tomography angiography

Optimized protocol of multiple post-processing techniques improves diagnostic accuracy of multidetector computed tomography in assessment of small bowel obstruction compared with conventional axial and coronal reformations

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World Journal of Gastroenterology 2019年第9期25卷 1100-1115页

作者： Lian-Qin Kuang Wei Tang Ran Li Cheng Cheng shuang-yue Tang Yi Wang Department of Radiology Army Medical Center of PLA Army Medical University Sichuan Key Laboratory of Medical Imaging Department of Radiology Affiliated Hospital of North Sichuan Medical College

BACKGROUND Axial and coronal reformations have been a widely used image post-processing protocol for the ordinary multidetector computed tomography(MDCT)examination of patients with small bowel obstruction(SBO) or other abdominal diseases. The diagnostic accuracy of MDCT for assessing SBO is expected to be further improved through the use of multiple post-processing *** To systemically evaluate the diagnostic accuracy and efficiency of an optimized protocol using multiple post-processing techniques for MDCT assessment of SBO and secondary bowel *** This retrospective cross-sectional study included 106 patients with clinically suspected SBO. Two readers applied three protocols to image post-processing and interpretation of patients' MDCT volume data. We compared the three protocols based on time spent, number of images, diagnostic self-confidence,agreement, detection rate, and accuracy of detection of SBO and secondary bowel *** Protocol 2 resulted in more time spent and number of images than protocols 1 and 3(P 0.05). Using protocol 3, both readers added multiple postprocessing techniques at frequencies of 29.2% and 34.9%, respectively, for obstruction cause, and 32.1% and 30.2%, respectively, for secondary bowel ischemia. Protocols 2 and 3 had higher total detection rates of obstruction cause and secondary bowel ischemia than protocol 1(P 0.05). The accuracy, sensitivity,specificity, positive predictive value and negative predictive value of protocols 2 and 3 were superior to those of protocol 1 for evaluating obstruction cause and secondary bowel *** Our optimized protocol of multiple post-processing techniques can both guarantee efficiency and improve diagnostic accuracy of MDCT for assessing SBO and secondary bowel ischemia.

关键词： Intestine Intestinal obstruction Multidetector computed tomography Diagnostic techniques and procedures

Association between 5-HTR1A gene C-1019G polymorphism and antidepressant response in patients with major depressive disorder:A meta-analysis

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World Journal of Psychiatry 2024年第10期14卷 1573-1582页

作者： Huai-Neng Wu shuang-yue Zhu Li-Na Zhang Bian-Hong Shen Lian-Lian Xu Department of Psychiatry Affiliated Mental Health Center and Hangzhou Seventh People’s HospitalZhejiang University School of MedicineHangzhou 310013Zhejiang ProvinceChina

BACKGROUND Major depressive disorder(MDD)is a substantial global health concern,and its treatment is complicated by the variability in individual response to *** To consolidate research and clarify the impact of genetic variation on MDD treatment *** Adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines,a systematic search across PubMed,EMBASE,Web of Science,and the Cochrane Library was conducted without date restrictions,utilizing key terms related to MDD,serotonin 1A receptor polymorphism(5-HTR1A),C-1019G polymorphism,and antidepressant *** meeting inclusion criteria were thoroughly screened,and quality assessed using the Newcastle-Ottawa *** analyses,includingχ2 and I²values,were used to evaluate heterogeneity and fixed-effect or random-effect models were applied *** The initial search yielded 1216 articles,with 11 studies meeting criteria for *** of various genetic models showed no significant association between the 5-HTR1A C-1019G polymorphism and antidepressant *** heterogeneity was low to moderate,and no publication bias was detected through funnel plot symmetry and Egger's and Begg's *** This meta-analysis does not support a significant association between the 5-HTR1A C-1019G polymorphism and the efficacy of antidepressant treatment in *** findings call for further research with larger cohorts to substantiate these results and enhance the understanding of antidepressant pharmacogenetics.

关键词： Major depressive disorder Antidepressant efficacy 5-HTR1A gene C-1019G polymorphism Meta-analysis

Carbon dioxide levels and ventilation for running vehicle

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Journal of Environmental Science and Engineering 2009年第9期3卷 23-27,49页

作者： DENG Da-yue CHEN shuang-ji Research Institute of lndoor Environment Beijing Union University Beijing 100083 China

Factors contributing to ventilation quantity of the vehicle are ventilation modes, cabin characteristics and vehicle speeds. CO2 levels were investigated under different speeds and ventilation modes. Four modes were selected： A： vent closed and fan shut, B： vent closed and fan started, C： vent opened and fan shut, D： vent opened and fan started. In vent closed modes, CO2 levels reached several thousands of ppm in few minutes at any speeds. For mode C, CO2 levels exceeded the guideline at low speeds 50 km/h, while it reduced below one at higher speeds 80 km/h. Fan has no significant impact on ventilation during vent closed. The ventilation efficiency in each mode increased with the speed raising. To determine the ventilation rate of running vehicle, the experiment was implemented by using CO2 emitted from driver and passengers as tracer gas. Ventilation rate for the different modes and speeds were calculated.

关键词： pollution in vehicle carbon dioxide ventilation modes ventilation rates

Effect of Structure Pattern on the Performance of X80 Pipeline Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 874-877页

作者： REN Yi,LIU Wen-yue,WANG shuang,ZHANG Shuai (Technical Center of Anshan Iron & Steel Co.Ltd.,Anshan 114009,Liaoning,China) Anshan Iron & Steel Co Ltd Ctr Tech Anshan 114009 Liaoning Peoples R China

The microstructure,dislocation and precipitation phases of X80 pipeline steel produced with different processes were analyzed by optical microscope and transmission electron microscope (TEM) contrastively,and the influence of structure pattern on the performance of X80 pipeline steel was *** result shows that the effects of acicular ferrite grain size,precipitate phase distribution,dislocation density and morphology on the material strength,toughness and brittle transmission temperatures were distinct,and solid solution strengthening,fine grain strengthening,dislocation strengthening and precipitation strengthening were the strengthening ways of X80 pipeline steel.

关键词： pipeline steel acicular ferrite dislocation precipitated phase toughness

Measurement factors of pollutants inside vehicle

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Journal of Environmental Science and Engineering 2008年第1期2卷 41-45页

作者： DENG Da-yue CHEN shuang-ji Research Institute of Indoor Environment Beijing Union University Beijing 100083 China

The air quality inside vehicle is concerned widely in the world. The pollution inside vehicle is special serious in China. State Environmental Protection Administration of China is formulating the standard of air quality inside vehicle. However the measurement relates to many factors. Because of the small space, temperature easy changed, various ventilation modes, being close to pollution source of engine exhaust, there are differences between in-vehicle and indoor measurement. The influence of measuring factors was investigated. Those factors include temperature, preconditioning time, ventilation modes, engine state, and sampling fashion. The measuring mode and relating factors were discussed. The suggestion was offered.

关键词： air quality inside vehicle measurement method

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移民与接收国创新:质与量的思考

当代经济科学 2020年第6期42卷 25-37页

作者：张晶岳爽訾爽山东财经大学金融学院山东济南250014

现代社会中,移民作为一个重要的国际现象备受关注,而其对于接收国的创新影响却一直存有争议。本文利用2006—2015年间19个经济合作与发展组织成员国的相关数据,证实移民整体上显著地促进了接收国的创新能力提升,且主要是通过人力资本存... 详细信息

现代社会中,移民作为一个重要的国际现象备受关注,而其对于接收国的创新影响却一直存有争议。本文利用2006—2015年间19个经济合作与发展组织成员国的相关数据,证实移民整体上显著地促进了接收国的创新能力提升,且主要是通过人力资本存量和移民多样性这两种途径得以实现的。同时,研究证实移民总量越大,人力资本存量与移民多样性对接收国创新的影响越明显。本文的研究不仅突破了以往文献只针对高技术移民对接收国创新能力影响的探讨,并且进一步剖析了移民影响创新的途径,从而表明对于接收国创新能力的提升,尽管移民的“质”是根本因素,但是“量”的积累也不可忽视。

关键词：移民创新能力人力资本移民规模移民质量移民多样性