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Hybrid gradient vector fields for path-following guidance

Defence Technology（防务技术） 2023年第10期28卷 165-182页

作者： Yi-yang Zhao Zhen Yang Wei-ren Kong Hai-yin Piao Ji-chuan Huang xiao-feng lv De-yun Zhou School of Electronics and Information Northwestern Polytechnical UniversityXi’An710072China School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China The 93147th Unit of Chinese PLA Air Force Chengdu610091China

Guidance path-planning and following are two core technologies used for controlling un-manned aerial vehicles(UAVs)in both military and civilian applications.However,only a few approaches treat both the technologies simultaneously.In this study,an innovative hybrid gradient vector fields for path-following guidance(HGVFs-PFG)algorithm is proposed to control fixed-wing UAVs to follow a generated guidance path and oriented target curves in three-dimensional space,which can be any combination of straight lines,arcs,and helixes as motion primitives.The algorithm aids the creation of vector fields(VFs)for these motion primitives as well as the design of an effective switching strategy to ensure that only one VF is activated at any time to ensure that the complex paths are followed completely.The strategies designed in earlier studies have flaws that prevent the UAV from following arcs that make its turning angle too large.The proposed switching strategy solves this problem by introducing the concept of the virtual way-points.Finally,the performance of the HGVFs-PFG algorithm is verified using a reducedorder autopilot and four representative simulation scenarios.The simulation considers the constraints of the aircraft,and its results indicate that the algorithm performs well in following both lateral and longitudinal control,particularly for curved paths.In general,the proposed technical method is practical and competitive.

关键词： Unmanned aerial vehicle(UAV) Path-following guidance(PFG) Hybrid gradient vector field(HGVF) Switching strategy

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A randomized, open-label, multicentre study to evaluate plasma atherosclerotic biomarkers in patients with type 2 diabetes mellitus and arteriosclerosis obliterans when treated with Probucol and Cilostazol

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Journal of Geriatric Cardiology 2012年第3期9卷 228-236页

作者： xiao-Wei Ma xiao-Hui Guo Xin-Hua xiao Li-Xin Guo xiao-feng lv Quan-Min Li Yan Gao Department of Endocrinology Peking University First Hospital No. 7 of Xishiku Street Xicheng District Beijing 100034 China Department of Endocrinology Peking Union Medical College Hospital No.1 Shuaifuyuan Dongcheng District Beijing 100005 China Department of Endocrinology Peking Hospital No. 1 Dahua Road Dongdan Dongcheng District Beijing 100730 China Department of Endocrinology Military General Hospital of Peking PLA No.5 Nanmencang Dongsishitiao Dongcheng District Beifing 100070 China Department of Endocrinology Second Artillery Forces General Hospital of Peking PLA No.16 Xinjiekouwai Street Xicheng District Beijing 100088 China

ObjectivesTo 当在联合和 individually.MethodsIn 与 Probucol 正 Cilostazol 对待时，与类型 2 糖尿病 mellitus ( T2DM )和动脉硬化 obliteran ( ASO )在病人评估血浆动脉粥样硬化患者 biomarkers 这开标签的研究， 40-75 年的病人... 详细信息

ObjectivesTo 当在联合和 individually.MethodsIn 与 Probucol 正 Cilostazol 对待时，与类型 2 糖尿病 mellitus ( T2DM )和动脉硬化 obliteran ( ASO )在病人评估血浆动脉粥样硬化患者 biomarkers 这开标签的研究， 40-75 年的病人被使随机化独自收到常规治疗，或与 Cilostazol 100 mg 出价，或与 Probucol 250 mg 出价，或与两个在里面联合。端点在 12 weeks.ResultsOf 在血浆 biomarker 和安全包括了变化 200 使随机化病人， 165 为每协议并且 160 分别地为安全(QTc 间隔) 被设置。Probucol 显著地减少了全部的胆固醇(P <；0.001 ) ，低密度的脂蛋白胆固醇(LDL-C ) ，(P = 0.01 ) ，并且高密度的脂蛋白胆固醇(高级数据链路控制)(P <；0.001 ) 与常规治疗相比。Cilostazol 在增加高级数据链路控制是有效的(P = 0.002 ) 并且减少 triglycerides 层次(P <；0.01 ) 与常规治疗相比。向意义的一个趋势在氧化低密度的脂蛋白为变化为独自一个的常规治疗和 Probucol 正 Cilostazol 组之间的差别被观察(Ox-LDL， P = 0.065 ) 。biomarkers 越过治疗 groups.ConclusionsWe 被发现的留下的多数上的重要效果都没证实 Ox-LDL 能是在评估 biomarkers 之中的可能的血浆动脉粥样硬化患者 biomarker，它与在现出症状之前的潜的研究以前显示出的 T2DM 和 ASO 在病人反映了 Cilostazol 正 Probucol 的合作效果。

关键词：动脉粥样硬化生物标志物 2型糖尿病西洛他唑普罗布考治疗患者随机

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Enteroenteroanastomosis near adjacent ileocecal valve in infants

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World Journal of Gastroenterology 2012年第48期18卷 7314-7318页

作者： Wei-Wei Jiang xiao-Qun Xu Qi-Ming Geng Jie Zhang Huan Chen xiao-feng lv Chang-Gui Lu Wei-Bing Tang Department of Pediatric Surgery Nanjing Children's Hospital Affiliated to Nanjing Medical University

AIM:To investigate the feasibility and the effectiveness of ileoileostomy in the region adjacent to the ileocecal valve,which can retain the ileocecal valve in infants.METHODS:This is a retrospective review of 48 patients who underwent ileoileostomy in the region adjacent to the ileocecal valve(group 1) and 34 patients who underwent ileocecal resections and ileotransversanastomosis(group 2).Patients were monitored for the time to flatus,resumption of eating,length of hospital stay after surgery,serum total bile acid,vitamin B12 and postoperative complications.RESULTS:The time to flatus,time until resumption of eating and post-operative length of hospital stay showed no statistically significant differences between the two groups.Serum total bile acid and vitamin B12were not significantly different between the two groups at post-operative day 1 and day 3,but were significantly decreased at 1 wk after operation in group 2.None of the patients died or suffered from stomal leak in these two groups.However,the incidence of diarrhea,intestinal infection,disturbance of acid-base balance and water-electrolytes in group 1 was lower than in group 2.CONCLUSION:Ileoileostomy in the region adjacent to the ileocecal valve is safe and results in fewer complications than ileotransversanastomosis in infants.

关键词：婴幼儿维生素B12 显示时间肠道感染酸碱平衡胆汁酸并发症患者

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Incidence of congenital heart disease in Beijing, China

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Chinese Medical Journal 2009年第10期122卷 1128-1132页

作者： YANG Xue-yong LI xiao-feng lv xiao-dong LIU Ying-long Pediatric Cardiac Center Department of Surgery Cardiovascular Institute and Fu Wai Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100037 China

Background The incidence of congenital heart disease has been studied in developed countries for many years, but rarely in the mainland of China. Fetal echocardiographic screening for congenital heart disease was first performed in Beijing in the early 2000s, but the impact was not clear. The current study was undertaken to determine the incidence of congenital heart disease in Beijing, China and to estimate the impact of fetal echocardiography on the incidence of liveborn congenital heart disease.Methods The study involved all infants with congenital heart disease among the 84 062 total births in Beijing during the period of January 1 and December 31, 2007. An echocardiographic examination was performed on every baby suspected to have congenital heart disease, prenatally or/and postnatally.Results A total of 686 infants were shown to have congenital heart disease among 84 062 total births. The overall incidence was 8.2/1000 total births. Mothers of 128 of 151 babies diagnosed prenatally were chosen to terminate the pregnancy. Two of the 151 infants died in utero. A specific lesion was identified for each infant and the frequencies of lesions were determined for each class of infants （total births, stillbirths and live births）. The incidence of congenital heart disease in stillbirths and live births was 168.8/1000 and 6.7/1000, respectively. The difference between the incidence of total birth and the incidence of live birth was statistically significant （P 〈0.001）. Conclusions The incidence of liveborn congenital heart disease in Beijing is within the range reported in developed countries. Fetal echocardiography reduce significantly the incidence of liveborn congenital heart disease.

关键词： incidence congenital heart disease prenatal diagnosis fetal echocardiography pregnancy termination

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气流染色机用离心通风机的优化设计

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风机技术 2024年第1期66卷 30-37页

作者：吕晓峰张勇闻苏平王志恒国成于家懿沈鼓集团股份有限公司西安交通大学能源与动力工程学院

离心通风机是气流染色系统的核心部件,其性能优劣直接决定气流染色系统的染色质量和能耗水平。本文针对某气流染色机用离心通风机的气动性能和几何结构开展优化设计,以风机全压PtF和全压效率ηtF最大化为优化目标,利用基于人工神经网络... 详细信息

离心通风机是气流染色系统的核心部件,其性能优劣直接决定气流染色系统的染色质量和能耗水平。本文针对某气流染色机用离心通风机的气动性能和几何结构开展优化设计,以风机全压PtF和全压效率ηtF最大化为优化目标,利用基于人工神经网络构建的代理模型,结合带精英策略的遗传算法对离心通风机叶轮开展优化设计,同时基于叶轮与蜗壳耦合整机气动匹配条件下对蜗壳几何结构进行优化设计。试验结果表明,优化设计的离心通风机结构更紧凑,其全压PtF提升约500Pa,其全压效率ηtF提升约5%。

关键词：离心通风机优化设计性能试验

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Rupture of a giant jejunal mesenteric cystic lymphangioma misdiagnosed as ovarian torsion: A case report

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World Journal of Clinical Cases 2024年第4期12卷 847-852页

作者： Jing Xu Tie-feng lv Department of Hepatopathy Hangzhou Xixi HospitalHangzhou 310023Zhejiang ProvinceChina

BACKGROUND Cystic lymphangioma is a rare benign tumor that affects the lymphatic system.Mesenteric lymphangiomas in the small bowel are extremely uncommon.CASE SUMMARY We present a 21-year-old female patient who complained of abdominal pain.The diagnosis of ovarian torsion was suspected after abdominopelvic unenhanced computed tomography and ultrasound revealed a large cyst in contact with the bladder,ovary,and uterus.The patient underwent emergency laparotomy per-formed by gynecologists,but it was discovered that the cystic tumor originated from the jejunum.Gastrointestinal surgeons were then called in to perform a cystectomy.Pathological examination confirmed the diagnosis of cystic lymphangioma of the mesentery.The patient had an uneventful postoperative recovery.CONCLUSION Mesenteric lymphangiomas can cause abdominal pain,and imaging techniques can help determine their characteristics,location,and size.Complete surgical excision and pathological examination are considered the standard treatment and diagnostic method.

关键词： Rupture Jejunum Mesenteric cystic lymphangioma Ovarian torsion Surgical excision Pathological examination Case report

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Fast nuclear-spin gates and electrons−nuclei entanglement of neutral atoms in weak magnetic fields

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Frontiers of physics 2024年第2期19卷 179-203页

作者： xiao-feng Shi School of Physics Xidian UniversityXi’an 710071China

We present a novel class of Rydberg-mediated nuclear-spin entanglement in divalent atoms with global laser pulses.First,we show a fast nuclear-spin controlled phase gate of an arbitrary phase realizable either with two laser pulses when assisted by Stark shifts,or with three pulses.Second,we propose to create an electrons−nuclei-entangled state,which is named a super bell state(SBS)for it mimics a large Bell state incorporating three small Bell states.Third,we show a protocol to create a three-atom electrons-nuclei entangled state which contains the three-body W and Greenberger−Horne−Zeilinger(GHZ)states simultaneously.These protocols possess high intrinsic fidelities,do not require single-site Rydberg addressing,and can be executed with large Rydberg Rabi frequencies in a weak,Gauss-scale magnetic field.The latter two protocols can enable measurement-based preparation of Bell,hyperentangled,and GHZ states,and,specifically,SBS can enable quantum dense coding where one can share three classical bits of information by sending one particle.

关键词： nuclear-spin qubit electrons−nuclei entanglement super Bell state Greenberger−Horne−Zeilinger state Rydberg-mediated entanglement quantum dense coding

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A Generalized MSST Algorithm for Counting Points of Elliptic Curves over■

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Journal of Systems Science & Complexity 2024年第4期37卷 1738-1754页

作者： LI xiao lv Chang PAN Zhizhong Key Laboratory of Cyberspace Security Defense Institute of Information Engineering Chinese Academy of Sciences School of Cyber Security University of Chinese Academy of Sciences Huawei Technologies Co. Ltd.

Elliptic curve cryptography is an important part of nowaday's public key cryptosystem.Counting points of elliptic curves over finite fields is of great significance to the selection of safety curves.At present, there are many p-adic algorithms, such as SST algorithm, generalized AGM algorithm,Kedlaya algorithm, etc., which can deal with the situation of finite fields of small characteristics. In this paper, the authors generalize the MSST algorithm of characteristic 2 to general fields of odd characteristic, and propose the generalized MSST algorithm. The generalized MSST algorithm is achieved by combining the advantages of the SST algorithm and the generalized AGM algorithm. If the time complexity of the multiplication of two n-bit numbers is denoted as O（nμ）, then the time complexity of the generalized MSST algorithm is O■, which is the same as the improved SST algorithm. In practical experiments, the running time of the generalized MSST algorithm is less than that of the improved SST algorithm.

关键词： Elliptic curve generalized AGM algorithm generalized MSST algorithm SST algorithm

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A novel polyionic liquid with lubricity and viscosity-increasing dual functionalities as the additive in aqueous lubrication system

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Friction 2024年第4期12卷 698-710页

作者： Bo YU Kun ZOU Rui WANG Qiang CHEN Rui DONG xiao LIU Jiaying ZHANG Wenquan lv Qiangliang YU Meirong CAI feng ZHOU College of Science Nanjing Forestry UniversityNanjing 210037China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai Yantai 264006China Yantai Zhongke Research Institute of Advanced Materials and Green Chemical Engineering Yantai 264006China Institute of Polymer Materials Nanjing Forestry UniversityNanjing 210037China

The polyionic liquid poly-PEGMA-r-METAC(PPM)with quaternary ammonium has been synthesized and evaluated as additive in aqueous lubricating fluids.The rheological behavior of aqueous lubricating fluids with PPM has been characterized to confirm PPM’s function as a viscosity modifier.The tribological behavior of aqueous lubricating fluids with PPM has been investigated on SRV-V and MTM testing machines.It was found that PPM has excellent viscosity-increasing,lubricating,and anti-wear properties as an additive for aqueous,which can be attributed to the ability of PPM to form the protective film and boundary tribofilm generated from complex tribochemical reaction on rubbing surface.The obtained PPM with dual functions of anti-corrosion additives and viscosity index improver can play an important role in diverse lubrication regimes.

关键词： polyionic liquid lubricant additives viscosity modifier lubrication regime

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Area Operators on Bergman Spaces

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1161-1176页

作者： xiao Fen lv Jordi PAU Mao Fa WANG Department of Mathematics Huzhou UniversityHuzhou 313000P.R.China Departament de Matemàtiques i Informàtica Universitat de Barcelona08007 BarcelonaCataloniaSpain School of Mathematics and Statistics Wuhan UniversityWuhan 430072P.R.China

We completely characterize the boundedness of area operators from the Bergman spaces A_(α)^(p)(Bn)to the Lebesgue spaces L^(q)(S_(n))for all 0 详细信息

We completely characterize the boundedness of area operators from the Bergman spaces A_(α)^(p)(Bn)to the Lebesgue spaces L^(q)(S_(n))for all 0lve the cases left open there and extend the results to n-complex dimension.

关键词： Area operator Bergman space tent space area formula

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