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Impact of Different Rates of Nitrogen Supplementation on Soil PhysicochemicalProperties and Microbial Diversity in Goji Berry
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作者 Xiaojie Liang Wei An +4 位作者 Yuekun Li Yajun Wang Xiaoya Qin Yanhong Cui Shuchai Su 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期467-486,共20页
Goji berry(Lycium barbarum L.)is substantially dependent on nitrogen fertilizer application,which can signifi-cantly enhance fruit yield and Goji berry industrial development in Ningxia,China.This study aimed to analyz... Goji berry(Lycium barbarum L.)is substantially dependent on nitrogen fertilizer application,which can signifi-cantly enhance fruit yield and Goji berry industrial development in Ningxia,China.This study aimed to analyze the functions of differential nitrogen application rates including low(N1),medium(N2),and high(N3)levels in soil microbial community structure(bacterial and fungal)at 2 diverse soil depths(0-20,20-40 cm)through high-throughput sequencing technology by targeting 16S RNA gene and ITS1&ITS2 regions.All the observed physicochemical parameters exhibited significant improvement(p<0.05)with increased levels of nitrogen and the highest values for most parameters were observed at N2.However,pH decreased(p<0.05)gradually.The alpha and beta diversity analyses for bacterial and fungal communities’metagenome displayed more similarities than differences among all groups.The top bacterial and fungal phyla and genera suggested no obvious(p>0.05)differences among three group treatments(N1,N2,and N3).Furthermore,the functional enrichment analysis demonstrated significant(p<0.05)enrichment of quorum sensing,cysteine and methionine metabolism,and transcriptional machinery for bacterial communities,while various saprotrophic functional roles for fungal communities.Conclusively,moderately reducing the use of N-supplemented fertilizers is conducive to increasing soil nitrogen utilization rate,which can contribute to sustainable agriculture practices through improved soil quality,and microbial community structure and functions. 展开更多
关键词 Goji berry production Ningxia China differential nitrogen supplementation rates 16s RNA gene and IT1&IT2 region sequencing soil physicochemical properties
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D-S理论和Markov链组合的桥梁性能退化预测研究
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作者 杨国俊 田里 +2 位作者 唐光武 毛建博 杜永峰 《应用数学和力学》 CSCD 北大核心 2024年第4期416-428,共13页
为准确预测桥梁性能退化,考虑到数据随机性和微小扰动发生状态跳跃,提出了一种D-S(Dempster-Shafer)证据理论和Markov链组合的桥梁性能退化组合预测模型和性能退化率的概念.该模型基于指数平滑(exponential smoothing,ES)方法获得新的... 为准确预测桥梁性能退化,考虑到数据随机性和微小扰动发生状态跳跃,提出了一种D-S(Dempster-Shafer)证据理论和Markov链组合的桥梁性能退化组合预测模型和性能退化率的概念.该模型基于指数平滑(exponential smoothing,ES)方法获得新的预测数据序列,并利用Markov链和D-S理论不断进行优化,从而实现桥梁性能退化的组合预测.实际工程的应用结果表明:性能退化率可以直观地表征在梁性能退化的速度.其次,该模型的平均相对误差为1.54%,较于回归、灰色和模糊加权Markov链模型,精度分别提高了1.11%,0.88%和2.8%,而后验差比值为0.242,小于0.35;模型的标准差为9.021,相比其他模型分别减小了3.978,3.405和7.500,而变异系数为0.109,均小于其他模型,验证了组合预测模型在精度和稳定性方面的优越性,可为在役桥梁结构性能退化预测与维护提供理论基础. 展开更多
关键词 桥梁工程 性能退化预测 D-s证据理论 MARKOV链 组合预测模型 桥梁性能退化率
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经皮二氧化碳分压监测在硬质支气管镜下Feng′s EBUS-TBNB中的应用
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作者 骆玉兔 孙亚楠 +1 位作者 潘家华 万南生 《南通大学学报(医学版)》 2024年第1期45-48,共4页
目的:探讨经皮二氧化碳分压(transcutaneous partial pressure of carbon dioxide,PtcCO_(2))监测在硬质支气管镜下冯氏气管内超声引导纵隔切开活检(Feng′s endobronchial ultrasound-guided transbronchial node biopsy,Feng′s EBUS-... 目的:探讨经皮二氧化碳分压(transcutaneous partial pressure of carbon dioxide,PtcCO_(2))监测在硬质支气管镜下冯氏气管内超声引导纵隔切开活检(Feng′s endobronchial ultrasound-guided transbronchial node biopsy,Feng′s EBUS-TBNB)中的应用。方法:收集2019年8月—2022年8月期间天津医科大学总医院收治的纵隔疾病患者128例,随机分成Feng′s EBUS-TBNB组和支气管内超声引导针吸活检术(endobronchial ultrasound-guided transbronchial needle aspiration,EBUS-TBNA)组,患者均予高频喷射通气行硬质支气管镜下操作及PtcCO_(2)监测,EBUS-TBNA组患者行EBUS-TBNA,Feng′s EBUS-TBNB组患者行Feng′s EBUS-TBNB术,比较两组患者术前(T0)、通气开始时(T_(1))、通气10 min后(T_(2))、通气20 min后(T3)、通气30 min后(T_(4))、通气40 min后(T_(5))、通气50 min后(T_(6))、通气60 min后(T_(7))心率(heart rate,HR)、平均动脉压(mean arterial pressure,MAP)和PtcCO_(2)的变化。结果:T_(1)~T_(7)时,两组患者HR、MAP和PtcCO_(2)水平均明显高于T0时(P<0.05)。T0~T_(2)时,两组患者HR、MAP和PtcCO_(2)水平比较差异无统计学意义(P>0.05);T3~T_(5)时,Feng′s EBUS-TBNB组HR、MAP和PtcCO_(2)水平均明显高于EBUS-TBNA组(P<0.05);而T_(6)~T_(7)时,两组患者HR、MAP和PtcCO_(2)水平比较差异无统计学意义(P>0.05)。结论:将PtcCO_(2)应用于Feng′s EBUS-TBNB中,可间接反映患者HR、MAP水平变化,值得临床推广应用。 展开更多
关键词 纵隔疾病 经皮二氧化碳分压 硬质支气管镜 冯氏气管内超声引导纵隔切开活检 心率 平均动脉压
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多因素影响下的S型管道冲刷腐蚀速率分析
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作者 马忠贞 张友军 +1 位作者 吕雪飞 甘树坤 《吉林化工学院学报》 CAS 2024年第1期43-50,共8页
S型管道应用于输运过程中的复杂地形,在上下游弯头处,会形成不同程度的冲刷腐蚀,造成安全隐患。为分析其腐蚀影响因素,建立S型管道腐蚀模型,采用ANSYS的Workbench平台搭建Fluent模块对不同影响因素下的腐蚀模型进行研究,创建数据传输,... S型管道应用于输运过程中的复杂地形,在上下游弯头处,会形成不同程度的冲刷腐蚀,造成安全隐患。为分析其腐蚀影响因素,建立S型管道腐蚀模型,采用ANSYS的Workbench平台搭建Fluent模块对不同影响因素下的腐蚀模型进行研究,创建数据传输,进而研究流体在流入弯管后各因素与冲蚀速率的关系。结果表明,S型管道冲刷腐蚀受到多因素的影响,尤其是下游弯头处的冲刷腐蚀更为明显。适当减小颗粒物直径、颗粒物质量流量,增大管径和弯径比可以减缓腐蚀及减小腐蚀区域。研究可为管道安全稳定运行提供理论依据。 展开更多
关键词 DPM s型管 冲刷腐蚀 腐蚀速率 数值模拟
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H_(2)S分压对Q245R钢在H_(2)S-CO_(2)共存环境中腐蚀行为的影响
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作者 贾旭东 曾文广 +2 位作者 高秋英 王少龙 赵鹏 《石油管材与仪器》 2024年第1期23-28,共6页
为研究H_(2)S-CO_(2)共存环境下H_(2)S含量对Q245R钢腐蚀行为的影响机制,通过模拟某油气田现场工况,利用高温高压釜设备开展不同P_(H_(2)S)下Q245R钢在H_(2)S-CO_(2)环境中腐蚀性能试验,并采用金相显微镜、XRD、SEM和EDS等手段来分析Q2... 为研究H_(2)S-CO_(2)共存环境下H_(2)S含量对Q245R钢腐蚀行为的影响机制,通过模拟某油气田现场工况,利用高温高压釜设备开展不同P_(H_(2)S)下Q245R钢在H_(2)S-CO_(2)环境中腐蚀性能试验,并采用金相显微镜、XRD、SEM和EDS等手段来分析Q245R钢的点蚀、腐蚀形貌和腐蚀产物组成等。结果表明:随着P_(H_(2)S)由0.001 MPa增至0.11 MPa,Q245R钢均匀腐蚀速率增幅达196%,均匀腐蚀速率最大值为0.892 1 mm/a;腐蚀主控因素由CO_(2)腐蚀(P_(H_(2)S)=0.001~0.05 MPa)转变为H_(2)S腐蚀(P_(H_(2)S)=0.11 MPa),主要腐蚀产物由FeCO_(3)转变为FeS。由于腐蚀产物膜中的裂纹与孔洞等腐蚀微观通道的增加,以及反应溶液流动产生的腐蚀介质扩散,Q245R钢的腐蚀不断加剧。 展开更多
关键词 H_(2)s腐蚀 腐蚀速率 点蚀
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H_(2)S/CO_(2)的腐蚀机理及缓蚀体系的研究进展
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作者 白玉震 苏碧云 +2 位作者 朱晓艳 侯博礼 檀银银 《化工技术与开发》 CAS 2024年第3期36-40,49,共6页
在油田开采、集输、储运、油气水处理等环节,钢材的腐蚀问题普遍存在。为了将腐蚀风险降至最低,油气田常采用多种方法进行腐蚀防护,其中添加缓蚀剂的方法最为常用。本文综述了近年来在H_(2)S/CO_(2)腐蚀环境下,利用缓蚀剂来抑制金属表... 在油田开采、集输、储运、油气水处理等环节,钢材的腐蚀问题普遍存在。为了将腐蚀风险降至最低,油气田常采用多种方法进行腐蚀防护,其中添加缓蚀剂的方法最为常用。本文综述了近年来在H_(2)S/CO_(2)腐蚀环境下,利用缓蚀剂来抑制金属表面腐蚀的研究进展,论述了CO_(2)、H_(2)S浓度、温度、pH等主控因素对腐蚀程度的影响,对各类主流缓蚀药剂如咪唑啉类缓蚀剂、聚合物类缓蚀剂、曼尼希碱缓蚀剂和有机胺类缓蚀剂的作用效果、原理及优缺点进行了归纳总结,对药剂的研究前景和发展方向进行了展望。 展开更多
关键词 油田 H_(2)s/CO_(2) 腐蚀机理 缓蚀剂 缓蚀率
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Design of a Biomedical Device to Reduce Anxiety Experienced by Patients Diagnosed with Parkinson’s Disease
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作者 Madhini Vigneswaran Anjali Menon 《Journal of Biomedical Science and Engineering》 2024年第3期57-71,共15页
Parkinson’s disease (PD) is a neurodegenerative disease that occurs due to loss of nerve cells that produce dopamine in the brain, affecting approximately 4 million people worldwide. PD patients often feel an increas... Parkinson’s disease (PD) is a neurodegenerative disease that occurs due to loss of nerve cells that produce dopamine in the brain, affecting approximately 4 million people worldwide. PD patients often feel an increase in anxiety levels daily. While there are medications/exercises to help relieve anxiety, there are limited methods to reduce anxiety without the help of a caretaker. As a result, MEDIC Foundation, a non-profit organization in British Columbia, Canada, is designing an automated system that consists of a wristband and an application which uses vi-bration therapy to help reduce anxiety of PD patients. Literature reviews were conducted to document the project’s needs. Phase I of the project focused on de-veloping a prototype for the application and phase II on developing the wrist-band. The team developed prototypes of a wristband that automatically applies vibration near the median nerve as the heart rate variability (HRV) deviates away from the normal threshold of the user, and an application that displays real-time heart rate variability signals as well as provides for relaxation. The development of the prototype is still in early progress. By creating this automated system, we aim to provide a solution to senior PD patients to relieve anxiety independently. . 展开更多
关键词 Vibration Therapy Healthcare Application Parkinson’s Disease ANXIETY WRIsTBAND Heart rate Variability
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超100 Gbit/s PON:灵活速率和相干架构(特邀)
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作者 周骥 郭栋 张俊文 《光通信研究》 北大核心 2024年第1期25-29,共5页
2021年国际电联电信标准化部门(ITU-T)完成50 Gbit/s无源光网络(PON)的标准制定,当前设备商和运营商已经完成样机验证,ITU-T成立Beyond 50 Gbit/s PON讨论组开始研讨未来PON相关技术方案,因此Beyond 50 Gbit/s PON成为当前光通信领域的... 2021年国际电联电信标准化部门(ITU-T)完成50 Gbit/s无源光网络(PON)的标准制定,当前设备商和运营商已经完成样机验证,ITU-T成立Beyond 50 Gbit/s PON讨论组开始研讨未来PON相关技术方案,因此Beyond 50 Gbit/s PON成为当前光通信领域的研究热点。根据前几代PON标准的速率演进规律推测,Beyond 50 Gbit/s PON的速率预计将超过100 Gbit/s。文章将分析超100 Gbit/s PON面临的问题和挑战,重点介绍灵活速率PON和相干PON架构这两个潜在技术路径及其关键技术方案,为未来超100 Gbit/s PON的研究和标准制定提供参考。 展开更多
关键词 无源光网络 超100 Gbit/s 灵活速率 相干架构 灵活多址接入
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具有饱和恢复率的SEIR时滞模型的行波解
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作者 卫珍妮 《西北师范大学学报(自然科学版)》 2024年第1期20-29,共10页
研究一类具有饱和恢复率的SEIR时滞模型的行波解.首先,考虑一类二维系统初值问题的适定性;然后,通过构造一对有界的向量值上、下解得到一个闭凸集;最后,利用Schauder不动点定理证明:当基本再生数R^(0)>1,波速c>c^(*)时模型存在非... 研究一类具有饱和恢复率的SEIR时滞模型的行波解.首先,考虑一类二维系统初值问题的适定性;然后,通过构造一对有界的向量值上、下解得到一个闭凸集;最后,利用Schauder不动点定理证明:当基本再生数R^(0)>1,波速c>c^(*)时模型存在非平凡行波解. 展开更多
关键词 sEIR模型 饱和恢复率 时滞 行波解 sCHAUDER不动点定理
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高含CO_(2)低含H2S条件下温度对P110碳钢腐蚀规律的影响 被引量:1
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作者 胡广强 肖雯雯 +4 位作者 梁婷婷 任月 曲志豪 张玉楠 张雷 《腐蚀与防护》 CAS CSCD 北大核心 2023年第4期59-64,共6页
为了明确高含CO_(2)及少量H2S条件下,温度变化对石油管材P110钢腐蚀速率的影响,利用高温高压硫化氢反应釜开展了腐蚀模拟试验,利用失重法记录腐蚀速率。应用扫描电子显微镜(SEM)、X射线衍射仪(XRD)和激光共聚焦显微镜等,研究并分析了P11... 为了明确高含CO_(2)及少量H2S条件下,温度变化对石油管材P110钢腐蚀速率的影响,利用高温高压硫化氢反应釜开展了腐蚀模拟试验,利用失重法记录腐蚀速率。应用扫描电子显微镜(SEM)、X射线衍射仪(XRD)和激光共聚焦显微镜等,研究并分析了P110钢表面的腐蚀形貌和产物。结果表明:在1 MPa CO_(2)分压、20 kPa H2S分压和流速1 m/s条件下,P110钢管材均匀腐蚀速率随温度升高先增大后减小,在100℃附近达到峰值。当温度超过80℃时,P110钢表面腐蚀形态由全面腐蚀转变为局部腐蚀。随着温度的升高,P110钢表面腐蚀产物由富铁结构转变为富硫结构,致密的陨硫铁矿和磁黄铁矿阻碍腐蚀反应的离子扩散。此外,在60~100℃,温度升高会同时促进阴极反应和阳极反应,导致P110钢自腐蚀电流密度增加,腐蚀速率提高,而当温度继续由100℃升高至120℃时,P110钢自腐蚀电流密度减小,腐蚀过程逐渐受到抑制。 展开更多
关键词 CO_(2)-H_(2)s腐蚀 温度 腐蚀速率 局部腐蚀
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农业节水灌溉REITs项目IRR测算研究 被引量:2
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作者 王蕾 裴晓桃 +3 位作者 陈天惠 彭圣 孙丽萍 张建红 《中国水利》 2023年第11期67-72,共6页
通过农业节水灌溉特许经营项目REITs案例研究发现,基础设施特许经营项目存在价值漏损时,可采用修正的B-S期权模型进行估值,可分配现金流用于分红的比例越高,投资收益越高,但项目的看涨期权价值越低。在项目高溢价转让的情况下,银行贷款... 通过农业节水灌溉特许经营项目REITs案例研究发现,基础设施特许经营项目存在价值漏损时,可采用修正的B-S期权模型进行估值,可分配现金流用于分红的比例越高,投资收益越高,但项目的看涨期权价值越低。在项目高溢价转让的情况下,银行贷款比例越高、偿还时间越短,投资内部收益率(IRR)及投资收益可能越低;收益波动越大,看涨期权价值越大,但IRR可能会下降。采用B-S期权定价模型丰富了现有经营权类公募REITs资产估值方法,具有推广应用价值。对公募REITs产品在不同贷款比例、还款期限以及分红条件下确定合理投资收益,具有实践指导作用。 展开更多
关键词 特许经营 公募REITs B-s期权定价模型 投资内部收益率(IRR) 并购贷款 收益测算
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基于GNSS资料分析漾濞M_(S)6.4地震前应变时空演变特征
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作者 王伶俐 洪敏 +3 位作者 高涵 徐良叶 王岩 牛甜 《中国地震》 北大核心 2023年第1期116-127,共12页
基于云南省内及邻区2009-2020年GNSS观测数据解算结果,在各个测点时间序列和速度场的基础上,采用克里金插值方法估计区域应变率场;以连续基准站时间序列为约束,获取漾濞M_(S)6.4地震近场区域的块体应变时间序列.分析发现:漾濞地震发生... 基于云南省内及邻区2009-2020年GNSS观测数据解算结果,在各个测点时间序列和速度场的基础上,采用克里金插值方法估计区域应变率场;以连续基准站时间序列为约束,获取漾濞M_(S)6.4地震近场区域的块体应变时间序列.分析发现:漾濞地震发生在前期最大剪应变高值区以及面应变高梯度带的张压转换区,发震的时间处于区域应变积累速率逐渐降低的过程之后.震中近场区域均以NW向断层的右旋走滑应变积累为主,且大多呈现持续增强趋势,与漾濞地震的发震断层走向及其破裂特征一致.震前震区东部块体出现了短期应变趋势转折及反向加速的异常现象,反映了应力-应变积累在接近临界破裂状态时的非线性调整. 展开更多
关键词 漾濞M_(s)6.4地震 GNss 速度场 应变率场 时间序列
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S Phase Cell Percentage Normalized BrdU Incorporation Rate, a New Parameter for Determining S Arrest 被引量:2
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作者 ZHAO Peng FU Juan Ling +2 位作者 YAO Bi Yun JIA Yong Rui ZHOU Zong Can 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2014年第3期215-219,共5页
In this study, a new parameter, S phase cell percentage (S fraction) normalized BrdU (SFN-BrdU) incorporation rate, was introduced to detect $ arrest. The results showed a positive linear correlation between the B... In this study, a new parameter, S phase cell percentage (S fraction) normalized BrdU (SFN-BrdU) incorporation rate, was introduced to detect $ arrest. The results showed a positive linear correlation between the BrdU incorporation rate and the S fraction in unperturbed 16HBE cells. Theoretical analysis indicated that only S arrest could result in a decrease in the SFN-BrdU incorporation rate. Additionally, the decrease in SFN-BrdU incorporation rate and the activation of DNA damage checkpoints further demonstrated that S arrest was induced by diethyl sulfate treatment of 16HBE cells. In conclusion, $FN-BrdU incorporation rate can be used to detecting S arrest. 展开更多
关键词 BRDU rate s Phase Cell Percentage Normalized BrdU Incorporation rate a New Parameter for Determining s Arrest
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Ergodic Rate Analysis on Applying Antenna Selection in D2D Communication Underlaying Cellular Networks 被引量:2
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作者 Senjie Zhang Yuyang Wang +1 位作者 Zhiqiang He Shi Jin 《China Communications》 SCIE CSCD 2017年第11期167-184,共18页
By reusing the spectrum of a cellular network, device-to-device(D2D) communications is known to greatly improve the spectral efficiency bypassing the base station(BS) of the cellular network. Antenna selection is the ... By reusing the spectrum of a cellular network, device-to-device(D2D) communications is known to greatly improve the spectral efficiency bypassing the base station(BS) of the cellular network. Antenna selection is the most cost efficient scheme for interference management, which is crucial to D2D systems. This paper investigates the achievable rate performance of the D2D communication underlaying the cellular network where a multiple-antenna base station with antenna selection scheme is deployed. We derive an exact closed-form expression of the ergodic achievable rate. Also, using Jensen's inequality, two pairs of upper and lower bounds of the rate are derived and we validate the tightness of the two sets of bounds. Based on the bounds obtained, we analyze the ergodic achievable rate in noise-limited scenario, interference-limited high SNR scenario and larger-scale antenna systems. Our analysis shows that the presence of D2D users could be counter-productive if the SNR at cellular UE is high. Further analysis shows that the relationship between the ergodic rate and the number of antennas it positive, but keeps decreasing as the antenna number increasing. These show the inefficiency of antenna selection in D2D interference management. 展开更多
关键词 antenna selection D2D communication ergodic achievable rate Jensen’s inequality massive MIMO
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Modeling and forecasting exchange rate volatility in Bangladesh using GARCH models:a comparison based on normal and Student's t-error distribution 被引量:2
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作者 S.M.Abdullah Salina Siddiqua +1 位作者 Muhammad Shahadat Hossain Siddiquee Nazmul Hossain 《Financial Innovation》 2017年第1期238-256,共19页
Background:Modeling exchange rate volatility has remained crucially important because of its diverse implications.This study aimed to address the issue of error distribution assumption in modeling and forecasting exch... Background:Modeling exchange rate volatility has remained crucially important because of its diverse implications.This study aimed to address the issue of error distribution assumption in modeling and forecasting exchange rate volatility between the Bangladeshi taka(BDT)and the US dollar($).Methods:Using daily exchange rates for 7 years(January 1,2008,to April 30,2015),this study attempted to model dynamics following generalized autoregressive conditional heteroscedastic(GARCH),asymmetric power ARCH(APARCH),exponential generalized autoregressive conditional heteroscedstic(EGARCH),threshold generalized autoregressive conditional heteroscedstic(TGARCH),and integrated generalized autoregressive conditional heteroscedstic(IGARCH)processes under both normal and Student’s t-distribution assumptions for errors.Results and Conclusions:It was found that,in contrast with the normal distribution,the application of Student’s t-distribution for errors helped the models satisfy the diagnostic tests and show improved forecasting accuracy.With such error distribution for out-of-sample volatility forecasting,AR(2)–GARCH(1,1)is considered the best. 展开更多
关键词 Exchange rate VOLATILITY ARCH GARCH student’s t Error distribution
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Predictive Model for Corrosion Rate of Oil Tubes in CO_2/H_2S Coexistent Environment Part Ⅰ: Building of Model 被引量:4
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作者 李全安 白真权 +3 位作者 黄得志 张清 文九巴 李鹤林 《Journal of Southwest Jiaotong University(English Edition)》 2004年第2期141-147,共7页
Based on an analysis of the existing models of CO 2 corrosion in literatures and the autoclave simulative experiments, a predictive model of corrosion rate (r corr) in CO 2/H 2S corrosion for oil tubes has been ... Based on an analysis of the existing models of CO 2 corrosion in literatures and the autoclave simulative experiments, a predictive model of corrosion rate (r corr) in CO 2/H 2S corrosion for oil tubes has been established, in which r corr is expressed as a function of pH, temperature (T), pressure of CO 2 (P CO 2) and pressure of H 2S (P H 2S). The model has been verified by experimental data obtained on N80 steel. The improved features of the predictive model include the following aspects: (1) The influence of temperature on the protectiveness of corrosion film is taken into consideration for establishment of predictive model of the r corr in CO 2/H 2S corrosion. The Equations of scale temperature and scale factor are put forward, and they fit the experimental result very well. (2) The linear relationship still exists between ln r corr and ln P CO 2 in CO 2/H 2S corrosion (as same as that in CO 2 corrosion). Therefore, a correction factor as a function of P H 2S has been introduced into the predictive model in CO 2/H 2S corrosion. (3) The model is compatible with the main existing models. 展开更多
关键词 Predictive model CO 2/H 2s corrosion Corrosion rate scale temperature Oil tube
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Anomalies identification of Earth’s rotation rate time series (2012-2017) for possible correlation with strong earthquakes occurrence 被引量:1
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作者 Fabrizio Ambrosino Lenka Thinová +1 位作者 Milos Briestensky Carlo Sabbarese 《Geodesy and Geodynamics》 2019年第6期455-459,共5页
The analysis of the Earth’s rotation rate time series,from January 1,2012 till December 31,2017,is performed using two different time series analysis methods,both based on signal decomposition joined with forecasting... The analysis of the Earth’s rotation rate time series,from January 1,2012 till December 31,2017,is performed using two different time series analysis methods,both based on signal decomposition joined with forecasting approach.Anomalies in the time series are detected making the comparison between the raw signal and the forecasting one at the 95% confidence interval.The two methods show consistent results and the best is selected according to the evaluation of the prediction uncertainty.Both methods highlight correlations between detected anomalies in the Earth’s rotation rate time series and the world’s earthquakes occurrence with magnitude≥7 and/or number of events≥150 per day,within a time interval of ±10 days from each earthquake event.This study brings an innovation in the analysis of such time series and helps to better understand the extent of this relationship. 展开更多
关键词 Earth’s ROTATION rate Time series analysis ANOMALIEs detection EARTHQUAKE
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Nest survival rate of Reeves's pheasant(Syrmaticus reevesii) based on artificial nest experiments 被引量:1
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作者 Xu Luo Yu-Ze Zhao +2 位作者 Jing Ma Jian-Qiang Li Ji-Liang Xu 《Zoological Research》 CAS CSCD 2017年第1期49-54,共6页
To explore the nest survival rate of Reeves' s pheasant(Syrmaticus reevesii) and the nest-site factors that affect it, we conducted artificial nest experiments with reference to natural nests at Dongzhai National N... To explore the nest survival rate of Reeves' s pheasant(Syrmaticus reevesii) and the nest-site factors that affect it, we conducted artificial nest experiments with reference to natural nests at Dongzhai National Nature Reserve(DNNR), Henan Province and Pingjingguan, Hubei Province from April to June 2014 simulating the situation in its early and later breeding season. We also determined distance characteristics of the nest sites by Arc GIS 10.0. Nest survival models were constructed in Program MARK for data analysis. Results indicated that in the early breeding season, the apparent survival rate(ASR) in DNNR(52.4%) was significantly greater than that in Pingjingguan(13.5%), and the ASR in the later breeding season in DNNR(26.7%) was not indistinctively correlated with Pingjingguan(3.2%). The daily survival rate(DSR) in the later breeding season was 93.8% in DNNR and 92.0% in Pingjingguan, respectively. The DSRs were both negatively correlated with nest distance to forest edges and settlements. The DSR in Pingjingguan was positively correlated with nest distance to paths and negatively correlated with nest distance to water sources. However, the DSR in DNNR was negatively correlated with nest distance to paths but positively correlated with nest distance to water sources. 展开更多
关键词 Reevess pheasant syrmaUcus reevesfi Nest survival rate Artificial nest experiments.
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Weapons system portfolio selection based on the contribution rate evaluation of system of systems 被引量:10
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作者 DOU Yajie ZHOU Zhexuan +1 位作者 ZHAO Danling WEI Yong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第5期905-919,共15页
The weapons system portfolio selection problem arises at the equipment demonstration stage and deals with the military application requirements.Further,the contribution rate of the system is one of the important indic... The weapons system portfolio selection problem arises at the equipment demonstration stage and deals with the military application requirements.Further,the contribution rate of the system is one of the important indicators to evaluate the role of a system,which can facilitate the weapons system portfolio selection.Therefore,combining the system contribution rate with system portfolio selection is the focus of this study.It also focuses on calculating the contribution rates of multiple equipment systems with various types of capabilities.The contribution rate is measured by establishing a hierarchical multi-criteria value model from three dimensions.Based on the value model,the feasible portfolios are developed under certain cost constraints and the optimal weapons system portfolios are obtained by using the classification optimization selection strategy.Finally,an illustrative example is presented to verify the feasibility of the proposed model. 展开更多
关键词 WEAPON sYsTEM sYsTEM of systems (sos) portfolioselection CONTRIBUTION rate EVALUATION DECIsION analysis
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Variations of the Earth's rotation rate and cyclic processes in geodynamics 被引量:1
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作者 B.W. Levin E.V. Sasorova +3 位作者 G.M. Steblov A.V. Domanski A.S. Prytkov E.N. Tsyba 《Geodesy and Geodynamics》 2017年第3期206-212,共7页
The authors analyzed the relationship between variations of the Earth's rotation rate and the geodynamic processes within the Earth's body, including seismic activity, The rotation rate of a planet determines its un... The authors analyzed the relationship between variations of the Earth's rotation rate and the geodynamic processes within the Earth's body, including seismic activity, The rotation rate of a planet determines its uniaxial compression along the axis of rotation and the areas of various surface elements of the body. The Earth's ellipticity variations, caused naturally by the rotation rate variations, are manifested in vertical components of precise GPS measurements. Comparative analysis of these variations is considered in view of modern theoretical ideas concerning the Earth's figure. The results justify further research that is of interest for improvement of space svstems and technologiesi. 展开更多
关键词 Earth's rotation rate Earth's ellipticity Changes in the planet's figure seismic activity Pulsations of the vertical components of GPs measurements
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