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Influence of the Electrical Vehicle Charging on the Grid Harmonic

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Journal of Electronic Science and Technology 2017年第1期15卷 99-105页

作者： Cheng-Long Xia Yong-duan song Yang Luo School of Energy Science and Engineering University of Electronic Science and TechnologyChengdu 611731China

This paper described the impact of the electrical vehicle（EV） charging on the grid harmonic. In view of the randomness of the EV charging process, the harmonic admittance matrix method and superposition method were used to build the single and multiple EVs charging simulation model. By using Matlab as a simulation tool, we analyzed harmonic currents of single and multiple EVs chargers. The results show that the harmonic ratio is beyond the scope of the national harmonic standard. Finally a parallel hybrid active filter（PHAPF） was introduced for governance of *** experimental results show that net side harmonic currents are significantly reduced by using the PHAPF and meet the national standard GB/Z17625.6-2003 regulations limit.

关键词： harmonic superposition charging currents governance regulations battery impedance rectifier beyond

Noether＇s Theorem of Nonholonomic Systems in Optimal Control

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Acta Mathematicae Applicatae Sinica 2016年第4期32卷 875-882页

作者： Ping-ping CAI duan song Jing-li FU Institute of Mathematical Physics Zhejiang Sci-Tech University Hangzhou 310018 China Eastern Liaodong University Shenyang 118000 China

In this paper, we extend Noether＇s theorem to nonholonomic constraints systems in optimal control. We present a systematic way to calculate conserved quantities along the Pontryagin extremals for optimal control problems with nonholonomic constraints, which are invariant under the parameter groups of infinitesimal transformations that change all （time, state, control） variables. Meanwhile, the Noether equalities corresponding to the conservation laws are given. Then, we obtain a new version of Noether＇s theorem to optimal control systems. An example is given to illustrate the application of these results.

关键词： nonholonommic system symmetry conservation law Noether's theorem optimal control

Face Detection under Complex Background and Illumination

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Journal of Electronic Science and Technology 2015年第1期13卷 78-82页

作者： Shao-Dong Lv Yong-duan song Mei Xu Cong-Ying Huang School of Energy Science and Engineering University of Electronic Science and Technology

For face detection under complex background and illumination, a detection method that combines the skin color segmentation and cost-sensitive Adaboost algorithm is proposed in this paper. First, by using the characteristic of human skin color clustering in the color space, the skin color area in YC b C r color space is extracted and a large number of irrelevant backgrounds are excluded; then for remedying the deficiencies of Adaboost algorithm, the cost-sensitive function is introduced into the Adaboost algorithm; finally the skin color segmentation and cost-sensitive Adaboost algorithm are combined for the face detection. Experimental results show that the proposed detection method has a higher detection rate and detection speed, which can more adapt to the actual field environment.

关键词： Adaboost cost-sensitive learning face detection skin color segmentation

构造Birkhoff动力学函数的Santilli第二方法的简化

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物理学报 2014年第14期63卷 193-197页

作者：宋端辽东学院影像物理教研室丹东118001

研究力学系统Birkhoff动力学函数的构造方法.Santilli第二方法是目前构造Birkhoff动力学函数时常用的方法之一,但研究发现其计算公式存在冗余项.通过具体的证明得到了简化的Santilli第二方法,从而为自伴随系统Birkhoff动力学函数的构造... 详细信息

研究力学系统Birkhoff动力学函数的构造方法.Santilli第二方法是目前构造Birkhoff动力学函数时常用的方法之一,但研究发现其计算公式存在冗余项.通过具体的证明得到了简化的Santilli第二方法,从而为自伴随系统Birkhoff动力学函数的构造提供了更为简洁的计算公式.举例说明结果的应用.

关键词： Birkhoff系统 Birkhoff动力学函数 Santilli第二方法

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约束优化问题的序列近似方法收敛性

大连理工大学学报 2016年第3期56卷 313-320页

作者：段庆松大连理工大学数学科学学院辽宁大连116024

对抽象约束优化问题的序列近似方法的收敛性进行讨论,证明了在目标函数序列连续收敛和约束集合序列收敛的条件下,序列近似问题的全局最优值收敛到原问题的最优值.进一步,证明了在序列近似问题目标函数和约束集合具有某些单调性质的前提... 详细信息

对抽象约束优化问题的序列近似方法的收敛性进行讨论,证明了在目标函数序列连续收敛和约束集合序列收敛的条件下,序列近似问题的全局最优值收敛到原问题的最优值.进一步,证明了在序列近似问题目标函数和约束集合具有某些单调性质的前提下,把目标函数序列连续收敛减弱到上图收敛,该结论仍然成立.最后,将这一结果用于分析互补约束优化问题的光滑化方法的收敛性中.

关键词：连续收敛上图收敛全局最优解互补约束优化

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肺良恶性肿块的CT误诊分析

中国介入影像与治疗学 2012年第10期9卷 732-735页

作者：宋段赤峰学院附属医院CT/MR室内蒙古赤峰024000

目的探讨肺良恶性肿块的CT征象,分析CT误诊的原因。方法收集经病理及临床、影像学随诊证实的肺癌患者87例及同期CT误诊的良性肿瘤43例,分析其影像学表现及CT误诊原因。结果 87例肺癌中,CT正确诊断46例,误诊41例;误诊和确诊的肺癌在分叶... 详细信息

目的探讨肺良恶性肿块的CT征象,分析CT误诊的原因。方法收集经病理及临床、影像学随诊证实的肺癌患者87例及同期CT误诊的良性肿瘤43例,分析其影像学表现及CT误诊原因。结果 87例肺癌中,CT正确诊断46例,误诊41例;误诊和确诊的肺癌在分叶征、毛刺征、胸膜凹陷征及淋巴结肿大、浅/深分叶征象的出现率的差异有统计学意义(P均0.05)。依据分叶征、毛刺征、血管集束征、支气管气相和胸膜凹陷征分为3个等级,将肺癌出现上述征象0～1个为不典型(等级1),2～3个为较典型(等级2),4～5个为典型(等级3),误诊和确诊肺癌在等级上差异有统计学意义(χ2=12.548,P=0.002)。结论导致CT误诊肺良恶性肿块,既有征象不典型、技术检查不足等原因,也有诊断医师对征象把握不准、经验不足等主观因素。

关键词：肺肿瘤结核,肺体层摄影术,X线计算机误诊

Role of interventional endovascular therapy for delayed hemorrhage after pancreaticoduodenectomy

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Chinese Medical Journal 2010年第21期123卷 3110-3117页

作者： WANG Zhi-jun WANG Mao-qiang LIU Feng-yong duan Feng song Peng FAN Qing-sheng Department of Interventional Radiology Chinese People's Liberation Army General Hospital Beijing 100853 China

Background Delayed massive hemorrhage （DMH） after pancreaticoduodenectomy （PD） is a sedous complication and one of the most common causes of mortality after PD. Its ideal management remains unclear. This paper is to present our experience in the endovascular treatment of patients with DMH after PD using different techniques and *** During a seven years period, 19 patients （fifteen men, four women） with DMH arter PD were treated with endovascular procedures, including transcatheter arterial embolization （TAE） with coils embolization in eight cases, with coils plus N-butyl-2-cyanoacrylate （NBCA）-Lipiodol mixture in six cases, and stent-graft placement in five cases. The mean age of the patients was 58.2 years. Follow-up, including clinical condition, liver function tests, and Doppler ultrasound examinations, was *** The immediate technical success rate was 84.2% （16/19）. There were no significant procedure-related complications. Hemostasis was not achieved with interventional procedures in three patients： one died of uncontrolled bleeding four days after the second TAE, and two patients required emergency laparotomy without re-angiography because of worsening clinical status. Among the 16 patients with successfully stopped bleeding who became hemodynamically stable after the procedure without evidence of further bleeding, two patients died during the peri-interventional procedure period because of multiple organ failure, and fourteen patients survived to hospital discharge. The mean length of follow-up was 14.6 months. Recurrent bleeding after discharge did not occur in any of these cases. Clinical and laboratory follow-up findings were unremarkable. Doppler ultrasound examinatation verified patency of the hepatic artery in the four patients with stent-graft placement during the follow-up period （5 months-29 months; mean, 15.3 months）.Conclusions Interventional endovascular procedure is a safe and technically feasible solution to control D

关键词： pancreaticoduodenectomy delayed massive hemorrhage hepatic artery pseudoaneurysm interventional radiology

Duration of Human Immunodeficiency Virus Infection at Diagnosis among New Human Immunodeficiency Virus Cases in Dehong, Yunnan, China, 2008-2015

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Chinese Medical Journal 2018年第16期131卷 1936-1943页

作者： Ai-Hua Li Zun-You Wu Zhen Jiang Jennifer M. McGoogan Yan Zhao song duan National Center for AIDS/STD Control and Prevention Chinese Center for Disease Control and Prevention Beijing 102206 China Department of Epidemiology University of California Los Angeles California USA Dehong Prefecture Center for Disease Control and Prevention Mangshi Yunnan 678400 China

Background： On diagnosis of human immunodeficiency virus （HIV） infection, a person may have been infected already for many years. This study aimed to estimate the duration of HIV infection at the time of diagnosis. Methods： Newly diagnosed HIV cases in Dehong, China, from 2008 to 2015 were studied. Duration of infection at the time of diagnosis was calculated using the first CD4 cell count result after diagnosis and a CD4 depletion model of disease progression. Multiple linear regression analysis was used to investigate the associated risk factors. Results： A total of 5867 new HIV cases were enrolled. Overall, mean duration of infection was 6.3 years （95% confidence interval [CI]： 6.2, 6.5）. After adjusting for confounding, significantly shorter durations of infection were observed among participants who were female （beta： -0.37, 95% CI： -0.64, -0.09）, Dai ethnicity （beta： -0.28, 95% CI： -0.57, 0.01 ）, and infected through injecting drug use （beta： -1.82, 95% CI： -2.25, -1.39）. Compared to the hospital setting, durations were shorter for those diagnosed in any other settings, and compared to 2008, durations were shorter for those diagnosed all years after 2010. Conclusion： Although the reduction in duration of infection at the time of diagnosis observed in Dehong was significant, it may not have had a meaningful impact.

关键词： China Delayed Diagnosis Human lmmunodeficiency Virus Infection

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虚拟现实建模语言在三维地震可视化中的应用

煤炭学报 2001年第2期26卷 126-128页

作者：宋端智张爱敏中国矿业大学江苏徐州221008

使用虚拟现实建模语言 (VRML)实现了层状地质体的三维显示 .实例表明VRML具有直观、易学的特点 ,不需要使用者掌握深厚的数学和计算机图形学知识 ,而且图形绘制结果方便用户交互 .

关键词：虚拟现实建模语言可视化地震层位纹理层状地质体 VRML