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Imaging findings of primary monomorphic epitheliotropic intestinal T-cell lymphoma:A case report 被引量:1
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作者 Wen-Jian Tang Shu-Hua Luo +6 位作者 Zhen Wu Yuan Kang Bo Lan Zhi-Qiang Zhang Jun-Yuan Zhong Jian-PingZhong Chun-Ju Wen 《World Journal of Gastrointestinal Oncology》 2025年第5期484-491,共8页
BACKGROUND Monomorphic epitheliotropic intestinal T-cell lymphoma(MEITL)is an uncom-mon and highly aggressive form of lymphoma that represents less than 1%of all non-Hodgkin’s lymphomas.At present,few reports have fo... BACKGROUND Monomorphic epitheliotropic intestinal T-cell lymphoma(MEITL)is an uncom-mon and highly aggressive form of lymphoma that represents less than 1%of all non-Hodgkin’s lymphomas.At present,few reports have focused on the imaging findings of MEITL,which poses significant challenges for clinical diagnosis.A 78-year-old female with recurrent vomiting and abdominal distension was admitted to our hospital.Magnetic resonance and^(18)F-fluorodeoxyglucose positron emission tomography/computed tomography(^(18)F-FDG PET/CT)examinations revealed multiple segmental malignant tumors in the small intestine with me-senteric lymph node metastasis.An endoscopic biopsy revealed MEITL.After three cycles of reduced-dose cyclophosphamide,vinorelbine,and prednisone che-motherapy,follow-up^(18)F-FDG PET/CT demonstrated a partial response to treatment.The patient was still alive after 6 months of follow-up.CONCLUSION Magnetic resonance imaging serves as a valuable tool in detecting malignant tumor lesions of MEITL,whereas^(18)F-FDG PET/CT offers additional assistance in tumor staging and assessing treatment efficacy. 展开更多
关键词 Intestinal cancer T-cell lymphoma Imaging findings ^(18)F-fluorodeoxyglucose positron emission tomography/computed tomography Case report
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Direction finding for wideband signal and multi-target with interferometer
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作者 PENG Bo SUN Jikang LI Chao 《Journal of Systems Engineering and Electronics》 2025年第5期1132-1139,共8页
According to the measurement principle of the traditional interferometer,a narrowband signal model is established and used,however,for wideband signals or multiple signals,this model is invalid.For the problems of dir... According to the measurement principle of the traditional interferometer,a narrowband signal model is established and used,however,for wideband signals or multiple signals,this model is invalid.For the problems of direction finding with interferometer for wideband signals and multiple signals scene,a frequency domain phase interferometer is proposed and the concrete implementation scheme is given.The proposed method computes the phase difference in frequency domain,and finds multi-target results with judging the spectrum amplitude changing,and uses the frequency phase difference to compute the arrival angle.Theoretical analysis and simulation results show that the proposed method effectively solves the problem of the angle estimation with phase interferometer for wideband signals,and has good performance in multiple signals scene with nonoverlapping spectrum or partially overlapping.In addition,the wider the signal bandwidth,the better direction finding performance of this algorithm. 展开更多
关键词 phase interferometer wideband signal direction finding multi-signal direction finding frequency domain interferometer
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The assessment tools and influencing factors of benefit finding in patients with chronic diseases: a scoping review
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作者 Xiao-Ge Ding Yin-Ji Jin 《Nursing Communications》 2025年第1期1-8,共8页
To describe and analyze the current status of benefit-finding research in patients with chronic diseases and to provide a reference for clinical practice and future research in this field.Using Arksey and O’Malley’s... To describe and analyze the current status of benefit-finding research in patients with chronic diseases and to provide a reference for clinical practice and future research in this field.Using Arksey and O’Malley’s scoping review methodology as a framework,we searched PubMed,Web of Science,Science Direct,and CINAHL(4 English databases);and China National Knowledge Infrastructure,the VIP Database for Chinese Technical Periodicals,the Wan Fang Database and China Biomedical Database(4 Chinese databases)for literature on benefit finding in patients with chronic diseases,with a search time frame of construction to April 20,2024,and the literature was screened,extracted,and summarized.A total of 44 papers were included,comprising 18 in Chinese and 26 in English.Among them,a total of 19 assessment tools were used,and the influential factors investigated were categorized into socio-demographic characteristics,disease-related characteristics,psychological and behavioral characteristics,coping styles,and social support.Benefit finding is found to be a positive psychological experience and important for patients with chronic diseases,and the influencing factors are complex and diverse,with a wide range of assessment tools.However,domestic tools lack autonomy and specificity.Clinical caregivers and staff should develop relevant assessment tools and formulate a personalized research plan based on the characteristics of patients with chronic diseases in China to promote the adoption of healthy lifestyles by patients with chronic diseases,improve their self-management ability,and provide a practical basis for improving the quality of life of patients with chronic diseases. 展开更多
关键词 patients with chronic diseases benefit finding assessment tools scoping review
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Comparative Study of CPLEX and D-Wave for Track Finding Resolution
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作者 Duy Dao Hervé Kerivin +1 位作者 Philippe Lacomme Bogdan Vulpescu 《Journal of Quantum Computing》 2025年第1期39-54,共16页
Track finding is a complex optimization problem,originally introduced in particle physics for the reconstruction of the trajectories of particles.A track is typically composed of several consecutive segments,which tog... Track finding is a complex optimization problem,originally introduced in particle physics for the reconstruction of the trajectories of particles.A track is typically composed of several consecutive segments,which together form a smooth curve without any bifurcations.In this paper,we investigate various modeling approaches to assess their effectiveness and impact when applied to track finding,using both quantum and classical methods.We present implementations of three classical models using CPLEX,two quantum models on actual D-Wave quantum computers,and one quantummodel on a D-Wave simulator.The results show that,while CPLEX provides better results than D-Wave on small instances,D-Wave is able to propose solutions in shorter computation times for large instances,although the gap with the optimal solution tends to increase.To the best of our knowledge,this is the first numerical study comparing a non-quantum approach based on classical algorithms(Simplex and Branch and Bound)used in commercial software with a quantum approach offered by D-Wave.The results do not show the quantum supremacy typically expected,but they do demonstrate that quantum solutions can be competitive with classical approaches,and even more efficient than some classical modeling and solving methods. 展开更多
关键词 Quantum annealing track finding D-WAVE quadratic/linear models CPLEX
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Evaluation of pathological findings in predicting postoperative endoscopic recurrence in Crohn’s disease:A retrospective cohort study
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作者 Işıl Karabulut ErdinçÇetinkaya +2 位作者 Nesrin Turhan Oyku Tayfur Yurekli Mesut Tez 《World Journal of Gastrointestinal Surgery》 2025年第9期73-78,共6页
BACKGROUND Crohn’s disease(CD)patients with intestinal involvement often require surgical intervention due to resistance to medical therapy.Postoperative recurrence remains a significant challenge,with the Rutgeerts ... BACKGROUND Crohn’s disease(CD)patients with intestinal involvement often require surgical intervention due to resistance to medical therapy.Postoperative recurrence remains a significant challenge,with the Rutgeerts score commonly used to predict endoscopic recurrence.AIM To evaluate the relationship between microscopic and macroscopic pathological findings in resected intestinal specimens and the Rutgeerts score to predict endoscopic recurrence in CD patients.METHODS This retrospective cohort study included 32 patients over 18 years of age with intestinal CD who underwent surgery at General Surgery Clinic of Ankara Bilkent City Hospital between November 2019 and October 2023.Resection specimens were histopathologically re-examined,and postoperative colonoscopy reports were classified according to the Rutgeerts score.The association between pathological findings and endoscopic recurrence was analyzed statistically.RESULTS No significant association was found between macroscopic findings and Rutgeerts scores or endoscopic recurrence(P>0.05).However,the presence and severity of neutrophilic cryptitis(P=0.035)and crypt abscesses(P=0.010)in microscopic findings were significantly associated with higher Rutgeerts scores,indicating a parallel increase with endoscopic recurrence.Other microscopic findings showed no significant correlation with Rutgeerts scores or endoscopic recurrence(P>0.05).CONCLUSION The presence of neutrophilic cryptitis and crypt abscesses in resected intestinal specimens of CD patients increases the likelihood of endoscopic recurrence.Early postoperative medical treatment and close endoscopic follow-up may benefit high-risk patients to prevent recurrence,with treatment decisions made by a weekly multidisciplinary council involving General Surgery,Gastroenterology,and Radiology. 展开更多
关键词 Crohn’s disease Endoscopic recurrence Pathological findings Rutgeerts score Predicting
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Studies of track finding for long-lived particles at the Super Tau-Charm Facility
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作者 Hao Li Hang Zhou +3 位作者 Jin Zhang Xing-Tao Huang Jie Yang Xiao-Cong Ai 《Nuclear Science and Techniques》 2025年第9期175-186,共12页
Reconstructing the trajectories of charged particles in high-energy physics experiments is a complex task,particularly for long-lived particles.At the future Super Tau-Charm Facility(STCF),such particles are expected ... Reconstructing the trajectories of charged particles in high-energy physics experiments is a complex task,particularly for long-lived particles.At the future Super Tau-Charm Facility(STCF),such particles are expected to appear in several key benchmark physics processes.A Common Tracking Software was used to reconstruct the trajectories of long-lived particles,revealing that the track-finding performance of the widely used combinatorial Kalman filter is limited by its seeding algorithm.This limitation can be mitigated by guiding the combinatorial Kalman filter using initial tracks provided by the Hough transform.The track-finding performance of the combined Hough transform and combinatorial Kalman filter was evaluated using the process J∕ψ→Λ(→pπ−)Λ(→pπ+)at STCF. 展开更多
关键词 Track finding A Common Tracking Software Hough transform Long-lived particles
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Ocular findings of the patients with congenital leptin deficiency under long-term leptin replacement therapy
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作者 Ozlem Candan Sevde Nur Fırat 《International Journal of Ophthalmology(English edition)》 2025年第10期1949-1957,共9页
AIM:To analyze the ocular findings of patients who received lifelong leptin therapy due to congenital leptin deficiency(CLD),an extremely rare condition.METHODS:A prospective,cross-sectional comparative study was perf... AIM:To analyze the ocular findings of patients who received lifelong leptin therapy due to congenital leptin deficiency(CLD),an extremely rare condition.METHODS:A prospective,cross-sectional comparative study was performed on six patients with CLD and 13 healthy age-and sex-matched controls.The central corneal thickness(CCT),anterior chamber depth(ACD),axial length(AL),keratometry(K1,K2),optical coherence tomography(OCT),and OCT angiography parameters were compared between the leptin and control groups at the baseline visit.The change in these measurements in leptin patients over a two-year period was analyzed.RESULTS:CLD patients had lower mean AL,ACD,and CCT(P≤0.012 for all).Mean K1,K2(P≤0.047 for both),choroidal thickness(P≤0.001),and central ganglion cell layer(GCL)thickness(P=0.029)were higher in the leptin group.Perifoveal superficial capillary plexus(SCP)density was decreased in all quadrants except the temporal region(P<0.05),and parafoveal deep capillary plexus(DCP)density was decreased in the superior hemisphere,temporal quadrant(P≤0.036 for both)and nasal quadrant(P=0.048)in the leptin group.During the two-year follow-up,no changes in anterior and posterior segment measurements were observed in the leptin patients,except for subfoveal choroidal thickness(P<0.001).CONCLUSION:CLD patients exhibit structural alterations in both the anterior and posterior segments of the eye,including notable changes in retinal and choroidal vasculature.However,there is limited evidence concerning the influence of leptin therapy on the eye. 展开更多
关键词 congenital leptin deficiency leptin replacement treatment ocular findings axial length
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Deception analysis of threat source direction finding in trajectory planning by FDA radar
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作者 WANG Bo WANG Gang +2 位作者 LI Yonglin YANG Rennong ZHAO Yu 《Journal of Systems Engineering and Electronics》 2025年第6期1488-1500,共13页
Electronic reconnaissance units commonly utilize an interferometer direction-finding system to measure the incoming direction of radar radiation signals.This approach enables the accurate determination of threat sourc... Electronic reconnaissance units commonly utilize an interferometer direction-finding system to measure the incoming direction of radar radiation signals.This approach enables the accurate determination of threat source locations,which is essential for devising route plans oriented toward flight path generation.When a frequency diverse array(FDA)system is adopted by ground radars,errors are introduced into the angle measurements of the passive direction finding system.To address this issue,this study starts with FDA model establishment and equiphasic surface characteristics analysis and analyzes the principles of FDA deception in identifying one-dimensional single-baseline interferometer directions.Additionally,the Cramer-Rao bounds of the signal carrier frequency estimation error and angle measurement error during the interferometer’s direction finding process are considered.The simulation results verify that the one-dimensional single-baseline interferometer direction finding system can be deceived by the FDA radar,and the FDA with a sine frequency offset exhibits the optimum deception effect. 展开更多
关键词 route planning frequency diverse array(FDA) INTERFEROMETER direction finding deception Cramer-Rao bound
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Efficacy and safety of GW117 tablets in major depressive disorder:a randomised,double-blind,placebocontrolled,phase 2 dose-finding study
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作者 Yifeng Shen Xiaonan Hao +16 位作者 Xiaoning Shi Zhiping Tao Xueqin Yu Xueyi Wang Xiaolan Di Haibo Yang Yingli Zhang Jie Li Zhiqiang Wang Guangyong Zhang Jingli Wang Zhiwei Jiang Ruiluan Wang Jingjing Liu Zhaoji Dong Wei Gu Hongyan Zhang 《General Psychiatry》 2025年第6期468-478,共11页
Background GW117(N-(2-(6-chloro-7-deuteromethoxynaphthalen-1-yl)ethyl)acetamide)is a dual-acting agent(MT1/MT2 agonist,5-HT_(2C)antagonist)with prior evidence of antidepressant efficacy and favourable safety.Aims To p... Background GW117(N-(2-(6-chloro-7-deuteromethoxynaphthalen-1-yl)ethyl)acetamide)is a dual-acting agent(MT1/MT2 agonist,5-HT_(2C)antagonist)with prior evidence of antidepressant efficacy and favourable safety.Aims To preliminarily evaluate the efficacy and safety of GW117 in major depressive disorder(MDD)and to explore the optimal dosing.Methods A total of 280 eligible patients aged 18-65years with MDD were randomly assigned(1:1:1:1)to8 weeks of double-blind treatment with fixed doses of GW117 tablets(20,40,60 mg/day)or placebo.The primary endpoint was the change from baseline to Week 8 in the total score of the Hamilton Rating Scale for Depression-17item(HAMD-17).Key secondary endpoints included changes in the Montgomery-?sberg Depression Rating Scale(MADRS)total score over the same period.Results In the full analysis set(n=276),GW117 showed numerically greater reductions versus placebo in the HAMD-17 and MADRS total scores,as well as higher response rates at Week 8.However,these differences did not reach statistical significance,potentially due to a high placebo response and other contributing factors.In a post hoc analysis of an optimal subgroup(baseline HAMD-17>24 or insomnia factor>4),GW117 showed efficacy in improving multidimensional symptoms,including insomnia.The 20 mg dose demonstrated a significant3.66-point greater reduction in MADRS(p=0.026)and a23.16%higher response rate(p=0.013)compared with placebo.GW117 was well-tolerated,with no cases of alanine aminotransferase or aspartate aminotransferase exceeding 3×the upper limit of normal and no concerning safety signals reported.Conclusions This exploratory study found that GW117demonstrated encouraging antidepressant efficacy and a favourable safety profile in patients with MDD.Although differences versus placebo did not reach statistical significance in the overall population,GW11720 mg monotherapy showed significant improvements in multidimensional depressive symptoms,including insomnia,in the optimal response subgroup.No hepatotoxicity was reported,supporting its promising therapeutic potential for further clinical development. 展开更多
关键词 HAMD major depressive disorder mdd major depressive disorder dose finding study safety MADRS gw efficacy
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Systemic and dermatological findings of immunoglobulin A vasculitis in a black child:A case report
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作者 Khulud Mahmood Nurani Gloria Natalia +1 位作者 Najib Kadernani Khalid Kadernani 《World Journal of Clinical Cases》 2025年第35期46-51,共6页
BACKGROUND Immunoglobulin A(IgA)vasculitis,formerly known as Henoch-Schönlein purpura,is a small vessel vasculitis predominantly affecting children.It commonly presents with a triad of purpuric rash,arthralgia,an... BACKGROUND Immunoglobulin A(IgA)vasculitis,formerly known as Henoch-Schönlein purpura,is a small vessel vasculitis predominantly affecting children.It commonly presents with a triad of purpuric rash,arthralgia,and abdominal pain.However,dermatologic manifestations of IgA vasculitis in black-skinned individuals are poorly documented in literature.CASE SUMMARY This case report describes an 11-year-old black girl with acute onset of rash,joint pain,and abdominal pain,subsequently diagnosed with IgA vasculitis.CONCLUSION The case highlights the importance of early recognition and supportive management in ensuring a favorable outcome,particularly in dark-skinned populations. 展开更多
关键词 Immunoglobulin A vasculitis Henoch-Schönlein purpura Pediatric vasculitis Purpura ARTHRALGIA Abdominal pain Black-skinned Dermatologic findings Case report
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多载荷组合下气承式膜结构煤棚找形受载分析
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作者 董明望 付国涛 +4 位作者 辜勇 郭笑海 乔磊 丁粤德 曲泓 《科学技术与工程》 北大核心 2026年第3期1183-1195,共13页
近年来气承式膜结构煤棚在极端风雪天气下事故频发,实际工程中此类煤棚需承受多种载荷的组合作用,这对其形态求解和受载分析提出了更高的要求。采用ANSYS的APDL模块自编程序进行找形分析并验证其可靠性,考虑气承式膜结构煤棚在风载荷作... 近年来气承式膜结构煤棚在极端风雪天气下事故频发,实际工程中此类煤棚需承受多种载荷的组合作用,这对其形态求解和受载分析提出了更高的要求。采用ANSYS的APDL模块自编程序进行找形分析并验证其可靠性,考虑气承式膜结构煤棚在风载荷作用下膜面与流场的流固耦合效应以及风载荷的波动性,对工程实例进行计算流体力学(computational fluid dynamics,CFD)分析,计算其表面风压和风振系数,并参考《建筑结构载荷规范》设计了9种载荷组合,由此形成75种载荷组合工况对其最大膜面应力与膜面位移进行校核。结果表明,该结构满足规范要求;载荷组合作用时会发生耦合作用,所得的响应不具备线性;其失效形式可能为强度不足而非位移超限;在气承式膜结构设计过程中,气膜的形状尺寸与风向角是设计验算所必须考虑的。 展开更多
关键词 气承式膜结构 煤棚 载荷组合 找形 CFD分析
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面向多机异步测向系统的多目标数据关联算法
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作者 周晓 孙子豪 +2 位作者 苏盈 王丽 牟新刚 《系统工程与电子技术》 北大核心 2026年第2期392-401,共10页
针对多载机协同光电探测系统执行多目标搜索任务时的测向数据关联问题,提出一种基于异步测向定位模型的数据关联算法。首先分析出传统关联代价模型的代价函数受测向数据异步采集的影响较大,再利用传感器误差等先验参数构建基本约束对关... 针对多载机协同光电探测系统执行多目标搜索任务时的测向数据关联问题,提出一种基于异步测向定位模型的数据关联算法。首先分析出传统关联代价模型的代价函数受测向数据异步采集的影响较大,再利用传感器误差等先验参数构建基本约束对关联组合进行初步筛选,然后再通过光电探测系统的搜索原理构建异步测向关联模型进行代价关联。仿真实验结果表明,相比于其他关联模型,所提算法模型关联正确率维持在90%以上,受载机和目标数量影响更小,算法耗时相对较低,性能更高。 展开更多
关键词 测向定位模型 多目标 关联代价函数 数据关联算法
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基于ANCF法的高速铁路接触网接触悬挂系统找形研究
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作者 贾传果 谭牟 +3 位作者 赵进级 张智强 陈奋飞 杨佳 《振动与冲击》 北大核心 2026年第4期109-119,共11页
高速铁路接触网作为结构复杂的架空输电系统,在风荷载、地震作用、弓网耦合作用等情况下会产生动力响应,进行接触网接触悬挂系统的动力响应分析已经成为该领域研究的热点问题。接触悬挂系统的初始找形分析是接触网动力分析的基础,初始... 高速铁路接触网作为结构复杂的架空输电系统,在风荷载、地震作用、弓网耦合作用等情况下会产生动力响应,进行接触网接触悬挂系统的动力响应分析已经成为该领域研究的热点问题。接触悬挂系统的初始找形分析是接触网动力分析的基础,初始找形结果的准确性对动力分析至关重要。基于绝对节点坐标法(absolute nodal coordinate formulation,ANCF)和牛顿迭代法对悬链线悬挂系统进行找形研究。在研究过程中需先建立ANCF静力学平衡方程,并在此基础上确定牛顿迭代的基本方程和变量,而后通过单根索的找形结果验证此法的可靠性,最后分别对一跨标准模型与一个实际的多跨接触网接触悬挂系统进行找形研究,将二者吊弦长度的计算结果与欧洲标准EN 50318—2018中的参考数值进行对比计算后发现相对误差均不超过0.2%,验证了本找形方法的准确性和实用性。 展开更多
关键词 接触网 接触悬挂系统 绝对节点坐标法(ANCF) 找形
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大湾区科学论坛会址结构关键技术分析
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作者 傅剑波 区彤 +3 位作者 刘雪兵 张连飞 张佳武 林松伟 《建筑结构》 北大核心 2026年第1期33-40,共8页
大湾区科学论坛会址建筑造型复杂,对建筑整体的结构逻辑单元进行梳理,介绍了下部主体混凝土结构、钢屋盖、外侧幕墙一体设计的基本情况。针对项目造型复杂的特点,分析了在不规则V形钢筋混凝土框架结构内设置BRB约束屈曲支撑和减震楼梯... 大湾区科学论坛会址建筑造型复杂,对建筑整体的结构逻辑单元进行梳理,介绍了下部主体混凝土结构、钢屋盖、外侧幕墙一体设计的基本情况。针对项目造型复杂的特点,分析了在不规则V形钢筋混凝土框架结构内设置BRB约束屈曲支撑和减震楼梯的必要性;重点介绍了波浪形屋面采用的单层二次悬垂梁钢网格结构体系及找形方法;提取了单层悬垂梁钢网格的风洞试验数据,对悬垂梁钢网格屋盖进行应力和屈曲分析、温度计算、防连续倒塌分析、重要节点分析和施工模拟等精细分析。计算结果表明,结构体系合理,传力路径清晰,施工快捷方便,结构具备良好的抗震性能,特别是在沿海高风压地区悬垂屋面具有优越的抗风性能。 展开更多
关键词 单层悬垂钢网格结构 BRB约束屈曲支撑 减震楼梯 找形方法 施工模拟
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上海世博温室张弦铝合金网格结构设计关键技术研究
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作者 李瑞雄 贾水钟 李亚明 《建筑结构》 北大核心 2026年第1期25-32,共8页
以上海世博温室热带雨林馆(P3)为工程背景,分析了温室建筑的功能需求与形态特点。针对不规则曲面屋盖、大跨度平屋盖等设计难点,开展了结构体系选型与布置优化研究,从而创新开发了张弦铝合金网格结构新体系。该结构体系通过上弦铝合金... 以上海世博温室热带雨林馆(P3)为工程背景,分析了温室建筑的功能需求与形态特点。针对不规则曲面屋盖、大跨度平屋盖等设计难点,开展了结构体系选型与布置优化研究,从而创新开发了张弦铝合金网格结构新体系。该结构体系通过上弦铝合金网格与下弦双向拉索经撑杆连接,形成自平衡受力系统,有效解决了多边形铝合金结构面外刚度不足问题。为验证结构可靠性,剖析屋盖结构体系的自平衡受力特征,明确其荷载传递路径;探究温度荷载下屋盖结构变形与受力特点,完成风荷载、地震工况下的力学响应分析,并通过稳定性验算与断索失效模拟评估结构安全冗余。结果表明,新结构体系受力效率高,对复杂边界具有很好的适应性。最后结合基础设计,通过在外围钢柱底部设置通风沟,在不破坏外立面通透效果的前提下,解决了温室建筑实现自然通风的问题。 展开更多
关键词 张弦铝合金网格结构 多边形铝合金网格 温度荷载 结构体系 找形分析 自然通风
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胰腺腺鳞癌影像学表现分析
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作者 王超 邹金钊 +2 位作者 周鑫 吴志强 黄文诺 《医疗卫生装备》 2026年第2期66-71,共6页
目的:分析胰腺腺鳞癌(pancreatic adenosquamous carcinoma,PASC)的影像学表现,提高对PASC的影像学认识。方法:回顾性分析经术后病理证实的8例原发性胰腺腺鳞癌患者的临床、影像及病理资料。8例患者中2例行CT增强扫描,1例行CT平扫、MRI... 目的:分析胰腺腺鳞癌(pancreatic adenosquamous carcinoma,PASC)的影像学表现,提高对PASC的影像学认识。方法:回顾性分析经术后病理证实的8例原发性胰腺腺鳞癌患者的临床、影像及病理资料。8例患者中2例行CT增强扫描,1例行CT平扫、MRI平扫及MRI增强扫描,1例行CT平扫、CT增强扫描、MRI平扫及MRI增强扫描,4例行CT平扫及增强扫描。观察并记录病灶的位置、大小、形状、边界、密度/信号、强化特点及有无邻近组织侵犯或远处转移。术后均行常规HE及免疫组化染色。结果:8例PASC患者中男性患者6例、女性患者2例;年龄范围为55~77岁,平均年龄为64岁。病灶位于胰头部3例、胰体部4例、胰尾部1例;病灶长径范围为2.1~4.8 cm,平均长径约3.7 cm。CT平扫结果以不均匀的低密度灶为主,其中7例伴有囊变、坏死。MRI平扫结果显示,病灶信号欠均匀,T_(1)WI呈低信号,T_(2)WI呈等、稍高信号。CT和MRI增强扫描结果显示,病灶呈不均匀强化,囊变、坏死区域无强化,病灶周边见环形强化,呈中度、渐进性强化。8例PASC患者中有6例伴有病灶下游主胰管扩张,4例伴有胰尾萎缩;2例出现肝内转移,1例侵犯邻近胃壁。HE染色结果显示,鳞癌成分占肿瘤的30%以上;免疫组化染色结果显示,8例病灶中提示鳞癌相关的P40、P60、CK5/6及腺癌相关的CK7、CK8/18、CK19均呈阳性。结论:当胰腺恶性肿瘤伴有明显囊变、坏死,增强扫描病灶呈周边中度、渐进性强化时应考虑PASC,系统分析其影像学表现有助于提高PASC早期诊断的准确性。 展开更多
关键词 胰腺腺鳞癌 腺癌 鳞癌 CT MRI 影像学表现
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Optimal path finding algorithms based on SLSD road network model 被引量:3
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作者 张小国 王庆 龚福祥 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期558-562,共5页
A solution to compute the optimal path based on a single-line-single-directional(SLSD)road network model is proposed.Unlike the traditional road network model,in the SLSD conceptual model,being single-directional an... A solution to compute the optimal path based on a single-line-single-directional(SLSD)road network model is proposed.Unlike the traditional road network model,in the SLSD conceptual model,being single-directional and single-line style,a road is no longer a linkage of road nodes but abstracted as a network node.Similarly,a road node is abstracted as the linkage of two ordered single-directional roads.This model can describe turn restrictions,circular roads,and other real scenarios usually described using a super-graph.Then a computing framework for optimal path finding(OPF)is presented.It is proved that classical Dijkstra and A algorithms can be directly used for OPF computing of any real-world road networks by transferring a super-graph to an SLSD network.Finally,using Singapore road network data,the proposed conceptual model and its corresponding optimal path finding algorithms are validated using a two-step optimal path finding algorithm with a pre-computing strategy based on the SLSD road network. 展开更多
关键词 optimal path finding road network model conceptual model digital map vehicle navigation system A algorithm Dijkstra algorithm
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小型均匀圆阵高精度测向方法及系统实现
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作者 王昊天 晋良念 +1 位作者 唐龙 蒙淑娇 《现代防御技术》 北大核心 2026年第1期61-72,共12页
针对现有的圆阵干涉仪测向方法在系统实现方面存在算法复杂度高、时效性低的问题,提出了一种适用于系统实现的干涉仪测向方法,并将其运用到实际系统。该方法首先利用比幅测向结果改进常规模糊数范围计算方法,以此减小运算量,提升运算速... 针对现有的圆阵干涉仪测向方法在系统实现方面存在算法复杂度高、时效性低的问题,提出了一种适用于系统实现的干涉仪测向方法,并将其运用到实际系统。该方法首先利用比幅测向结果改进常规模糊数范围计算方法,以此减小运算量,提升运算速度;同时考虑到相同条件下频率越高比幅测向精度越高,联合频率信息和比幅测向结果实时地划分比幅范围;然后利用各基线的模糊多值相差较远,而真实角度具有唯一性的特点,实现对圆阵干涉仪测向解模糊;最后根据所提方法原理利用FPGA实现并设计了小型化八元均匀圆阵干涉仪宽带接收机。经过仿真实验和外场试验,证明了该系统能够实现对辐射源目标的高精度瞬时测向,测向精度可以达到1.5°,在工程应用中具有很高的实用价值。 展开更多
关键词 均匀圆阵 干涉仪测向 比幅测向 解模糊 小型化
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一种改进的无源定位算法
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作者 朱一鑫 付天晖 +2 位作者 冯士民 黄林 吴熙 《海军工程大学学报》 北大核心 2026年第1期34-38,共5页
针对在GPS定位误差或测向误差较大的情境下,传统定位算法难以满足高精度和高稳定性的问题,本文提出了一种基于球坐标系的加权平均无源定位算法。该算法综合考虑测试点与定位点对定位误差的影响,通过构建乘积权重矩阵,采用测试点与定位... 针对在GPS定位误差或测向误差较大的情境下,传统定位算法难以满足高精度和高稳定性的问题,本文提出了一种基于球坐标系的加权平均无源定位算法。该算法综合考虑测试点与定位点对定位误差的影响,通过构建乘积权重矩阵,采用测试点与定位点的加权平均来处理多条指向线的交点,从而获得辐射源的最优位置估计。仿真结果表明:与传统算法相比,所提出的方法在测向误差较大的情况下,定位精度可平均提升30 km。此外,该算法还增强了系统在不稳定环境中的适应能力,为解决无源定位系统在高误差环境下的测向定位问题提供了一种有效方法。 展开更多
关键词 无源定位 球坐标系 加权平均算法 测向定位
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多站测向交叉定位的定位精度研究
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作者 曹文焕 韩升明 陈超 《现代电子技术》 北大核心 2026年第5期51-55,共5页
对敌方雷达进行定位可以获取雷达位置,进而引导干扰和反辐射攻击,为获取电磁战场优势提供了先决条件。通常,采用无源定位的方式获取雷达位置,其中测向交叉定位法环境适应性好、所需设备量适中,是雷达无源定位中最广泛应用的方法。然而,... 对敌方雷达进行定位可以获取雷达位置,进而引导干扰和反辐射攻击,为获取电磁战场优势提供了先决条件。通常,采用无源定位的方式获取雷达位置,其中测向交叉定位法环境适应性好、所需设备量适中,是雷达无源定位中最广泛应用的方法。然而,多站测向交叉定位存在定位模糊区,模糊区越小,定位精度越高。为了分析定位精度,在定位原理的基础上,提出一种几何稀释度的精度计算方法。通过分析几何稀释度的计算公式,定位误差的影响因素包括测向误差、侦察站位置、侦察站数量和布站方式。仿真实验结果表明,提高测向精度、侦察站靠近目标、合理布站以及增加侦察站数量这四条措施可以有效提高定位精度。在实际应用中,可根据需要采取相应的措施来提高测向交叉定位的定位精度,从而得到更为精确的雷达目标位置信息,该方法具有一定的实用价值。 展开更多
关键词 测向交叉定位 定位精度 几何稀释度 测向精度 无源定位 布站方式
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