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基于聚焦变换解卷积的宽带稳健波束形成

哈尔滨工程大学学报（英文版） 2024年第2期23卷 425-433页

作者：生雪莉陆典于洋蔡晨阳 National Key Laboratory of Underwater Acoustic Technology Harbin Engineering UniversityHarbin 150001China Key Laboratory for Polar Acoustics and Application of Ministry of Education(Harbin Engineering University) Ministry of EducationHarbin 150001China College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China

In the field of array signal processing,uniform linear arrays(ULAs)are widely used to detect/separate a weak target and estimate its direction of arrival from interference and noise.Conventional beamforming(CBF)is robust but restricted by a wide mainlobe and high sidelobe level.Covariance-matrix-inversed beamforming techniques,such as the minimum variance distortionless response and multiple signal classification,are sensitive to signal mismatch and data snapshots and exhibit high-resolution performance because of the narrow mainlobe and low sidelobe level.Therefore,compared with the wideband CBF,this study proposes a robust focused-and-deconvolved conventional beamforming(RFD-CBF),utilizing the Richardson–lucy(R-L)iterative algorithm to deconvolve the focused conventional beam power of a half-wavelength spaced ULA.Then,the focused-and-deconvolved beam power achieves a narrower mainlobe and lower sidelobe level while retaining the robustness of wideband CBF.Moreover,compared with the wideband CBF,RFD-CBF can obtain a higher output signal-to-noise ratio(SNR).Finally,the performance of RFD-CBF is evaluated through numerical simulation and verified by sea trial data processing.

关键词： Wideband Beamforming Focusing transform Deconvolution High resolution Robust

Genome-wide association study and transcriptome analysis reveal new QTL and candidate genes for nitrogen-deficiency tolerance in rice

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The Crop Journal 2022年第4期10卷 942-951页

作者： Qing Li xueli lu Changjian Wang Lan Shen Liping Dai Jinli He Long Yang Peiyuan Li Yifeng Hong Qiang Zhang Guojun Dong Jiang Hu Guangheng Zhang Deyong Ren Zhenyu Gao Longbiao Guo Qian Qian Li Zhu Dali Zeng State Key Laboratory of Rice Biology China National Rice Research InstituteChinese Academy of Agricultural SciencesHangzhou 311401ZhejiangChina

The development of rice cultivars with improved nitrogen use efficiency(NUE)is desirable for sustainable agriculture.Achieving this goal depends in part on understanding how rice responds to low soil nitrogen(N)and identifying causative genes underlying this trait.To identify quantitative trait loci(QTL)or genes associated with low N response,we conducted a genome-wide association study(GWAS)using a diverse panel of 230 rice accessions and performed a transcriptomic investigation of rice accessions with differential responses to low N stress at two N levels.We detected 411 GWAS-associated genes in 5 QTL and 2722 differentially expressed genes in response to low N,of which 24 were identified by both methods and ranked according to gene annotations,literature queries,gene expression,and genetic diversity analysis.The large-scale datasets obtained from this study reveal low N-responsive characteristics and provide insights towards understanding the regulatory mechanisms of N-deficiency tolerance in rice,and the candidate genes or QTL would be valuable resources for increasing rice NUE via molecular biotechnology.

关键词： Nitrogen NUE Rice GWAS RNA-seq

接种AMF对‘阿坝’垂穗披碱草根系耐低温生理的影响

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草业科学 2024年第6期41卷 1384-1396页

作者：张海娟周学丽芦光新金鑫范月君青海大学农牧学院青海西宁810016 青海理工学院青海西宁810016 青海省高原气候变化及其生态环境效应重点实验室青海西宁810016 青海省草原改良试验站青海共和813000 青海农牧科技职业学院青海湟源812100

为明确丛枝菌根真菌(AMF)对禾本科牧草耐低温能力的影响,本研究以根内球囊霉(Glomus intraradices,GI)和‘阿坝’垂穗披碱草(Elymus nutans‘Aba’)为试验材料,通过盆栽法,探究了低温条件下[15℃/10℃,16 h/8 h(光照/黑暗)]接种根内球... 详细信息

为明确丛枝菌根真菌(AMF)对禾本科牧草耐低温能力的影响,本研究以根内球囊霉(Glomus intraradices,GI)和‘阿坝’垂穗披碱草(Elymus nutans‘Aba’)为试验材料,通过盆栽法,探究了低温条件下[15℃/10℃,16 h/8 h(光照/黑暗)]接种根内球囊霉对‘阿坝’垂穗披碱草根系生理特性的影响。结果表明:1)低温对‘阿坝’垂穗披碱草的菌根侵染率无显著影响(P>0.05)。2)低温增加了‘阿坝’垂穗披碱草根系中过氧化氢(H_(2)O_(2))和丙二醛(MDA)含量,降低了超氧阴离子产生速率(O_(2)^(·-)),而接种GI抑制了由低温引起的H2O2和MDA含量的积累,对O_(2)^(·-)的影响不显著。3)低温增加了超氧化物歧化酶(SOD)、过氧化物酶(POD)和抗坏血酸过氧化物酶(APX)活性,降低了过氧化氢酶(CAT)活性,其中SOD、POD和APX活性均是接种组(LT-AMF)显著低于不接种组(LT)(P<0.05)。4)低温显著增加了可溶性蛋白(SP)含量,降低了甜菜碱(Gb)含量,对游离脯氨酸(Pro)含量无显著影响,接种GI显著降低了SP含量,对Pro和Gb含量无显著影响。综上所述,接种GI能通过增加抗氧化酶活性和降低渗透胁迫强度增强‘阿坝’垂穗披碱草根系对低温的耐受能力。

关键词：丛枝菌根真菌低温禾本科根系活性氧类物质抗氧化酶渗透调节物质

血清Ang-2和HMGB1水平与脓毒症患者病情及预后相关性的研究

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宁夏医学杂志 2024年第6期46卷 465-469,F0003页

作者：卢燕王敏李学莉宁夏银川市第一人民医院宁夏银川750001 湖北省武汉市第一医院湖北武汉430022

目的探究血清血管生成素-2(Ang-2)和高迁移率族蛋白B1(HMGB1)水平与脓毒症患者病情及28天预后的相关性。方法回顾性分析41例脓毒症患者资料,根据患者28天的预后情况分为存活组和死亡组;根据患者病情严重程度将2组患者分别分为脓毒症... 详细信息

目的探究血清血管生成素-2(Ang-2)和高迁移率族蛋白B1(HMGB1)水平与脓毒症患者病情及28天预后的相关性。方法回顾性分析41例脓毒症患者资料,根据患者28天的预后情况分为存活组和死亡组;根据患者病情严重程度将2组患者分别分为脓毒症组和脓毒性休克组。记录所有入组患者的一般资料并进行第1天、第3天、第5天及第7天的APACHEⅡ评分,测定Ang-2和HMGB1水平。结果存活组与死亡组患者的一般资料比较差异无统计学意义。死亡组脓毒症休克患者占比及入科APACHEⅡ评分为(85.71%)和(29.29±5.99)分,均明显高于存活组(51.84%)和(24.96±5.84)分。2组患者血清Ang-2和HMGB1水平比较差异无统计学意义。第7天的HMGB1水平与脓毒症患者预后显著相关,而第1天、第3天、第5天的HMGB1水平及上述各时间点的Ang-2水平与患者预后均无相关性。各时间点血清Ang-2水平的算术平均值与APACHEⅡ评分的算术平均值呈正相关,HMGB1水平与APACHEⅡ评分并无相关性。联合第7天的APACHEⅡ评分、Ang-2和HMGB1水平的曲线下面积最大为0.78,灵敏度为92.9%,特异度为59.3%。联合第7天的Ang-2和HMGB1水平预测预后不良的曲线下面积为0.71,灵敏度为92.9%,特异度为55.6%。结论脓毒症患者第1天、第3天、第5天及第7天的平均血清Ang-2水平与病情严重程度呈正相关;联合脓毒症患者第7天的血清Ang-2和HMGB1水平对其预后进行评估灵敏度最高,明显高于单独某项指标的评估价值。

关键词：脓毒症血管生成素-2 高迁移率族蛋白B1 预后

吐哈盆地丘东洼陷三工河组致密砂岩油气成藏过程分析

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天然气地球科学 2024年第2期35卷 275-287页

作者：肖冬生王柏然姚宗森李志远贾雪丽鲁宽中国石油吐哈油田公司勘探开发研究院新疆哈密839009 中国石油大学(北京)地球科学学院北京102249 中国石油大学(北京)油气资源与探测国家重点实验室北京102249

台北凹陷三工河组致密砂岩油气藏是吐哈盆地现实的油气接替领域,油气成藏过程一直未得到清晰的认识,制约着该领域的高效勘探。综合应用盆地模拟、构造演化史分析、流体包裹体测试等手段,对丘东洼陷三工河组致密砂岩油气藏烃源岩生排烃... 详细信息

台北凹陷三工河组致密砂岩油气藏是吐哈盆地现实的油气接替领域,油气成藏过程一直未得到清晰的认识,制约着该领域的高效勘探。综合应用盆地模拟、构造演化史分析、流体包裹体测试等手段,对丘东洼陷三工河组致密砂岩油气藏烃源岩生排烃史、储层成岩演化史、区域构造演化史及油气充注史等关键成藏要素进行了模拟和分析,并对各成藏要素在地质历史中的匹配关系进行了系统研究。结果表明:烃源岩生排烃期、油气充注期、储层演化与构造背景的配置关系控制油气富集。丘东洼陷三工河组油气经历3期油气充注,第一期发生在早白垩世末期,在燕山Ⅱ幕的构造活动背景下,低熟原油在洼陷内低幅隆起和温吉桑构造高部位汇聚形成低熟油藏,由于该时期三工河组储层较为致密导致充注量有限;第二期充注为晚白垩世末,烃源岩处于成熟阶段并大量生油气,此时有机酸的形成改善了三工河组砂岩储层空间,有利于油气的充注,在温吉桑地区和丘东洼陷区低幅隆起部位(吉7H井附近)形成成熟油气藏;古近纪末期丘东洼陷下侏罗统烃源岩开始大量生气,此时储层已致密,洼陷区整体平缓且构造稳定,油气近源充注形成大规模致密凝析气藏(含油)并最终定型。研究证实丘东洼陷区三工河组具备大规模致密凝析气藏形成条件,是台北凹陷下侏罗统未来勘探的有利区域。

关键词：吐哈盆地丘东洼陷三工河组致密油气藏成藏过程

基于AL-BILSTMDN的输电线动态热极限概率预测

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电力系统及其自动化学报 2024年第6期36卷 110-118页

作者：孙辉卢雪立高正男胡姝博金田王钟辉大连理工大学电气工程学院大连116024 国网辽宁省电力有限公司电力科学研究院沈阳110055 国网辽宁省电力有限公司调度通信部沈阳110055

针对输电线动态热极限概率预测精度不足的问题,提出一种基于交替学习-双向长短时混合密度网络模型的动态热极限概率预测方法。该模型基于双向长短时混合密度网络抓取训练数据时序信息并实现动态热极限概率预测。同时,使用交替学习方法... 详细信息

针对输电线动态热极限概率预测精度不足的问题,提出一种基于交替学习-双向长短时混合密度网络模型的动态热极限概率预测方法。该模型基于双向长短时混合密度网络抓取训练数据时序信息并实现动态热极限概率预测。同时,使用交替学习方法对时序数据集中的复杂模式数据进行强化学习,即区分出训练集中具有较为复杂模式的部分,让复杂模式训练集和全部训练集在模型中交替迭代直至最优,从而解决不平衡数据集混叠造成的局部最优问题。通过辽宁省某地区实例分析显示,所提模型可提升预测精度、降低过载概率。

关键词：线路输送能力动态热极限概率预测动态增容神经网络

Intra-Organizational Social Media and Employee Idea Generation:Analysis based on the Spanning-Relevance Framework

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Journal of Systems Science and Systems Engineering 2022年第6期31卷 649-676页

作者： Benjiang lu Xunhua Gu Nianlong luo xueli Wang Guoqing Chen School of Business Nanjing UniversityNanjing 210093China School of Economics and Management Tsinghua UniversityBeijing 10084China Information Technology Center Tsinghua University Beijing 100084China China Retail Research Center School of Economics and ManagementTsinghua UniversityBeijing 100084China

Intra-organizational social media platforms are expected to help build a flexible corporate stage that facilitates employees'communication and leverages creative idea generation.However,whether and how these systems can expedite the creativity of employees remains unclear.This paper attempts to address the impacts of employees'social relationships on intra-organizational social media on their idea generation quantity and quality.Drawn upon the extant literature in the fields of information systems and organizational behavior,a theoretical model is postulated on the basis of analyzing the attributes of social ties and exchanged information content in light of a two-dimensional framework that juxtaposes boundary spanning and work relevance.The model is empirically tested using data obtained from two internal application systems of a large telecommunications company.Test results validate that employees'online social relationships with different attributes are discriminably associated with their group identification and proactive creativity.Meanwhile,proactive creativity and group identification both show the positive impacts on idea generation quantity,whereas only proactive creativity has a significant positive impact on idea generation quality.These findings contribute to the literature on intra-organizational social media and employee idea generation,by uncovering the links among employees'online social relationships,mental processes,and idea generation.

关键词： Intra-organizational social media online social relationship idea generation group identification proactivecreativity

Hydrothermal synthesis of zeolitic material from circulating fluidized bed combustion fly ash for the highly efficient removal of lead from aqueous solution

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Chinese Journal of Chemical Engineering 2022年第7期35卷 193-205页

作者： Zhibin Ma xueli Zhang Guangjun lu Yanxia Guo Huiping Song Fangqin Cheng State Environmental Protection Key Laboratory of Efficient Utilization Technology of Coal Waste Resources Collaborative Innovation Center of High Value-added Utilization of Coal-related WastesInstitute of Resources and Environmental EngineeringShanxi UniversityTaiyuan 030006China

The utilization of coal fly ash derived from circulating fluidized bed combustion(CFBFA)still faces great challenges because of its unique characteristics.In this study,a zeolitic material with Na-P1 zeolite as the main phase was successfully synthesized via a hydrothermal method by using CFBFA as the raw material.The effects of hydrothermal temperature,time,and added CTAB amount on the characterizations of synthesized materials were investigated by XRD,SEM,and XPS.The properties of the optimal zeolitic material and its adsorption performance for Pb^(2+)in aqueous solution were evaluated.The influences of pH,initial concentration,dosage,and temperature on Pb^(2+)adsorption were also examined.Results revealed the following optimal parameters for the synthesis of zeolitic material:NaOH concentration of 2 mol·L^(-1),solid-to-liquid ratio of 1:10 g·ml^(-1),hydrothermal temperature of 110℃,hydrothermal time of 9 h,and CTAB amount of 1 g(per 100 ml solution).The adsorption capacities of the zeolitic material reached 329.67,424.69,and 542.22 mg·g^(-1) when the pH values of aqueous solution were 5,6,and 7,respectively.The Pb^(2+)removal efficiency can reach more than 99%in aqueous solution with the initial concentrations of 100-300 mg·L^(-1) under pH 6 and suitable adsorbent dosage.The adsorption and kinetics of Pb^(2+)on the zeolitic material can be described by Langmuir isotherm and pseudo-second-order kinetic models,respectively.The ion exchange between Pb^(2+)and Na^(+)and chemisorption are the main adsorption mechanism.All these findings imply that the synthesis of low-cost adsorbent for Pb^(2+)removal from weak acid and neutral aqueous solution provides a highly effective method to utilize CFBFA.

关键词： Circulating fluidized bed(CFB)coal fly ash Hydrothermal treatment Zeolite Pb^(2+) Adsorption Waste treatment

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中耳神经源性肿瘤8例的诊治体会

中国耳鼻咽喉颅底外科杂志 2024年第1期30卷 22-25页

作者：庄璐费静杨婷钰申雪力廖娜李雷激西南医科大学附属医院耳鼻咽喉头颈外科四川泸州646000

目的探讨中耳神经源性肿瘤的临床特征、诊治方法及预后。方法回顾性分析2010年1月—2023年3月收治的8例经病理确诊为中耳神经源性肿瘤患者的临床资料。8例患者首发症状中以耳流脓为主4例,听力下降3例,面瘫1例。5例肿物突入外耳道,3例... 详细信息

目的探讨中耳神经源性肿瘤的临床特征、诊治方法及预后。方法回顾性分析2010年1月—2023年3月收治的8例经病理确诊为中耳神经源性肿瘤患者的临床资料。8例患者首发症状中以耳流脓为主4例,听力下降3例,面瘫1例。5例肿物突入外耳道,3例鼓膜紧张部穿孔。纯音测听示8例患者均伴有不同程度的听力下降,其中混合性聋4例、传导性聋3例、极重度感音神经性聋1例。结果所有患者均完善中耳CT及MRI,提示肿瘤累及中鼓室或鼓岬表面5例,累及面神经水平段3例,其中1例侵入中颅窝。8例患者均行乳突改良根治术,术后病理证实鼓室体副神经节瘤4例、面神经纤维瘤2例、面神经鞘膜瘤1例、中耳神经内分泌腺瘤1例;2例患者术前行活检分别诊断为中耳胆脂瘤和慢性化脓性中耳炎,术前病理误诊率为25%(2/8)。术后随访1个月至8年,目前尚无复发病例。结论中耳神经源性肿瘤发病率较低且临床表现各异,存在一定的误诊率,术前完善CT和增强MRI检查以及术后病理及免疫组化有助于明确诊断。手术是治疗该病的有效手段。

关键词：中耳神经源性肿瘤面瘫乳突根治术误诊