期刊文献+
共找到78篇文章
< 1 2 4 >
每页显示 20 50 100
UIT Redirect-on-Write快照技术助力电信级数据容灾
1
作者 蒋长坡 《中国新通信》 2008年第7期86-90,共5页
介绍UIT独特的逻辑快照技术,用指针重定向的方式减少每次磁盘做快照时的读写,及减少做快照的所需的磁盘容量。并且生成多个不同时间点的数据版本。另介绍UIT逻辑快照在电信级容灾项目里面的使用。
关键词 容灾 逻辑快照 PIT Redirect-on-Write UIT 电信级 数据保护
在线阅读 下载PDF
UIT BL2000提供高效经济的虚拟磁带库备份方案
2
《通信世界》 2008年第48期I0056-I0056,共1页
目前,对于关键业务数据,企业建立了各种各样的备份系统。如果客户采用传统磁带备份技术,那么客户在备份/恢复中将会遇到种种难题,包括备份/恢复过程太长、人力资源消耗太大、无法保证备份/恢复的成功、对于备份介质的管理非常复... 目前,对于关键业务数据,企业建立了各种各样的备份系统。如果客户采用传统磁带备份技术,那么客户在备份/恢复中将会遇到种种难题,包括备份/恢复过程太长、人力资源消耗太大、无法保证备份/恢复的成功、对于备份介质的管理非常复杂、恢复时间无法确定、介质成本和维护成本高昂等等。面对这些挑战,虚拟磁带库备份方案正成为客户关注的焦点。UIT新近推出的BL2000产品(如图所示),全面提供了高效、经济和可扩展的虚拟磁带库备份方案,为保护数据提供了优异选择。 展开更多
关键词 虚拟磁带库 备份方案 经济 备份/恢复 维护成本 业务数据 备份系统 备份技术
在线阅读 下载PDF
An Ultralytics YOLOv8-Based Approach for Road Detection in Snowy Environments in the Arctic Region of Norway 被引量:2
3
作者 Aqsa Rahim Fuqing Yuan Javad Barabady 《Computers, Materials & Continua》 2025年第6期4411-4428,共18页
In recent years,advancements in autonomous vehicle technology have accelerated,promising safer and more efficient transportation systems.However,achieving fully autonomous driving in challenging weather conditions,par... In recent years,advancements in autonomous vehicle technology have accelerated,promising safer and more efficient transportation systems.However,achieving fully autonomous driving in challenging weather conditions,particularly in snowy environments,remains a challenge.Snow-covered roads introduce unpredictable surface conditions,occlusions,and reduced visibility,that require robust and adaptive path detection algorithms.This paper presents an enhanced road detection framework for snowy environments,leveraging Simple Framework forContrastive Learning of Visual Representations(SimCLR)for Self-Supervised pretraining,hyperparameter optimization,and uncertainty-aware object detection to improve the performance of YouOnly Look Once version 8(YOLOv8).Themodel is trained and evaluated on a custom-built dataset collected from snowy roads in Tromsø,Norway,which covers a range of snow textures,illumination conditions,and road geometries.The proposed framework achieves scores in terms of mAP@50 equal to 99%and mAP@50–95 equal to 97%,demonstrating the effectiveness of YOLOv8 for real-time road detection in extreme winter conditions.The findings contribute to the safe and reliable deployment of autonomous vehicles in Arctic environments,enabling robust decision-making in hazardous weather conditions.This research lays the groundwork for more resilient perceptionmodels in self-driving systems,paving the way for the future development of intelligent and adaptive transportation networks. 展开更多
关键词 Autonomous vehicles self-driving vehicles road detection snow-covered roads YOLOv8 road detection using segmentation
在线阅读 下载PDF
Photo-responsive polypropylene/zinc oxide/polydopamine-TEMPO composite membranes with light-induced self-sterilization
4
作者 Huajie Wang Hao Peng +6 位作者 Wenhao Ji Jiaxin Wang Xiaoyan Du Wen Song Wen Zhang Fazli Wahid Ali Raza 《Nano Materials Science》 2025年第2期276-288,共13页
Face masks play a pivotal role in preventing infection transmission.However,the capture of infection-sourced particles in face masks poses challenges related to reuse,necessitating proper disposal.We developed a self-... Face masks play a pivotal role in preventing infection transmission.However,the capture of infection-sourced particles in face masks poses challenges related to reuse,necessitating proper disposal.We developed a self-sterilizable polypropylene-based membrane for face masks to address challenges associated with infection transmission prevention.The membrane,created using 3D printing,underwent functionalization with zinc oxide(ZnO)and polydopamine(PDA)-TEMPO to achieve broad-spectrum light absorption and facilitate self-sterilization through photocatalytic and photothermal effects upon light exposure.The hydrophobic surface(water contact angle:133±2°)minimized moisture accumulation,and the membrane exhibited robust mechanical properties,including shear strength(1.25±0.5kPa)and peel resistance strength(112.8±11.2kPa).The evaluation demonstrated stability in airflow(0-500cm^(3)/s)and excellent aerosol filtration efficiency(94.8±0.6%)for particles(PM 0.3,PM 2.5,PM 10),comparable to commercial masks.The membrane showed antibacterial efficacy over five uses in a simulated respiratory environment.Safety assessments confirmed biocompatibility through cytocompatibility and skin irritation assays.In conclusion,this membrane offers efficient filtration and photo-triggered sterilization,presenting a promising solution for next-generation face masks to address concerns related to reuse,disposal,and infection control. 展开更多
关键词 Face masks 3D printing Nanocomposites POLYDOPAMINE PHOTO-RESPONSIVE Self-sterilization
在线阅读 下载PDF
Characteristics and trends of bibliometric analysis on acupuncture:A cross-sectional study
5
作者 Zhi-Qiang Li Hui-Juan Cao +9 位作者 Heng Yin Yue Jiang Xue-Feng Wang Chen Shen Kun Wu Zi-Yi Qi Mei-Ling Wang You-Zhu Su Ling-Yao Kong Jian-Ping Liu 《Integrative Medicine Discovery》 2025年第3期1-11,共11页
Background:The bibliometrics of acupuncture are growing rapidly.However,the absence of reporting guidelines may lead to significant duplication and waste,thereby undermining the research’s value.To address this,a kno... Background:The bibliometrics of acupuncture are growing rapidly.However,the absence of reporting guidelines may lead to significant duplication and waste,thereby undermining the research’s value.To address this,a knowledge mapping was generated based on published studies to investigate the characteristics of bibliometric studies on acupuncture and the extent of duplicate publications,with the overarching goal of providing a comprehensive overview of the knowledge structure in this field.Methods:This cross-sectional study used three databases(PubMed,Web of Science,and Scopus)to identify relevant studies up to May 1,2024.In addition,the reference lists were retrieved as a supplement.To track research trends,we employed Microsoft Excel and R software to extract,code,and analyze information.Study selection,data extraction,and validation were performed independently by at least two reviewers.The reporting quality of included studies was assessed using the Preliminary guideline for reporting bibliometric reviews of the biomedical literature(BIBLIO).Results:Among the 6,221 bibliometric reviews examined,113 relevant publications were identified,80 focusing on various diseases/conditions.The annual number of publications has gradually increased,with the output in the past four years being 3.52 times higher than that before 2020.China(106)and Chengdu University of Traditional Chinese Medicine(16)have the highest number of publications.The most prolific author is Fan-Rong Liang,with six articles.The first bibliometric study,by Hai-Yan Li,was published in 2010.Journal of Pain Research,with 36 articles,holds the most publications.The top three diseases:diseases of the nervous system;symptoms,signs,or clinical findings not elsewhere classified;and mental,behavioral,or neurodevelopmental disorders.There may be potential duplication in research on 13 diseases/conditions,notably stroke,migraine,pain/analgesia,cancer pain,shoulder pain,facial paralysis/bell’s palsy,chronic pain,and cognitive impairment.In BIBLIO,the most frequently missing items are issues/topics(item 2),quality assessment(item 11),and descriptive findings(item 13).Conclusion:This study demonstrates that acupuncture bibliometrics is actively utilized to identify dominant diseases/conditions,aiding scholars in understand the knowledge structure and main topics.Although the number of related studies is increasing,with an average of 25 studies annually,overlap in some areas highlights the need for adherence to reporting guidelines and careful topic selection to ensure truly valuable insights and knowledge contributions.The adherence to BIBLIO’s 20 proposed items across analyzed articles,highlighting important in reporting practices. 展开更多
关键词 cross-sectional study ACUPUNCTURE BIBLIOMETRICS evidence mapping
暂未订购
Accurate cadmium(Ⅱ)detection with single crystalline α-Fe_(2)O_(3) nano-hexagonal modified screen-printed carbon electrode
6
作者 Selvakumar Palanisamy Murugan Velmurugan +4 位作者 G.Bharath Matteo Chiesa Rajesh Madhu Fedor V Kusmartsev Sridharan Balu 《Journal of Environmental Sciences》 2025年第8期635-644,共10页
Even in small concentrations,toxic metals like lead,cadmium,and mercury are dangerous to the environment and human health.Environmental monitoring depends on precisely identifying these heavy metals,particularly cadmi... Even in small concentrations,toxic metals like lead,cadmium,and mercury are dangerous to the environment and human health.Environmental monitoring depends on precisely identifying these heavy metals,particularly cadmium ions(Cd(Ⅱ)).In this study,we present a novel screen-printed carbon electrode(SPCE)modified with single crystallineα-Fe_(2)O_(3)nano-hexagons that functions as a sensor for detecting Cd(Ⅱ).The performance of the fabricated sensor was thoroughly assessed and compared with unmodified SPCE using the voltammetric method.The crystalline structure of the synthesizedα-Fe_(2)O_(3)nano-hexagons was confirmed through XRD,and surface analysis revealed an average diameter and thickness of 86 nm and 9 nm,respectively.Theα-Fe_(2)O_(3)modified SPCE yields a 7-fold enhanced response(at pH 5.0 vs.Ag/AgCl)to Cd(Ⅱ)than bare SPCE.The modified electrode effectively detects Cd(Ⅱ)with a linear response range of up to 333.0μmol/L and a detection limit of 0.65 nmol/L under ideal circumstances.This newly fabricated sensor offers significant potential for environmental monitoring applications by providing outstanding practicality,anti-interference ability,and repeatability for detecting Cd(Ⅱ)in water samples. 展开更多
关键词 α-Fe_(2)O_(3)nano-hexagons Screen-Printed Carbon electrode Electroanalysis Heavy metal ions detection Cadmium ion sensor Differential pulse voltammetry
原文传递
Role of deep learning in cognitive healthcare:Wearable signal analysis,algorithms,benefits,and challenges
7
作者 Md.Sakib Bin Alam Aiman Lameesa +4 位作者 Senzuti Sharmin Shaila Afrin Shams Forruque Ahmed Mohammad Reza Nikoo Amir H.Gandomi 《Digital Communications and Networks》 2025年第3期642-670,共29页
Deep Learning(DL)offers promising solutions for analyzing wearable signals and gaining valuable insights into cognitive disorders.While previous review studies have explored various aspects of DL in cognitive healthca... Deep Learning(DL)offers promising solutions for analyzing wearable signals and gaining valuable insights into cognitive disorders.While previous review studies have explored various aspects of DL in cognitive healthcare,there remains a lack of comprehensive analysis that integrates wearable signals,data processing techniques,and the broader applications,benefits,and challenges of DL methods.Addressing this limitation,our study provides an extensive review of DL’s role in cognitive healthcare,with a particular emphasis on wearables,data processing,and the inherent challenges in this field.This review also highlights the considerable promise of DL approaches in addressing a broad spectrum of cognitive issues.By enhancing the understanding and analysis of wearable signal modalities,DL models can achieve remarkable accuracy in cognitive healthcare.Convolutional Neural Network(CNN),Recurrent Neural Network(RNN),and Long Short-term Memory(LSTM)networks have demonstrated improved performance and effectiveness in the early diagnosis and progression monitoring of neurological disorders.Beyond cognitive impairment detection,DL has been applied to emotion recognition,sleep analysis,stress monitoring,and neurofeedback.These applications lead to advanced diagnosis,personalized treatment,early intervention,assistive technologies,remote monitoring,and reduced healthcare costs.Nevertheless,the integration of DL and wearable technologies presents several challenges,such as data quality,privacy,interpretability,model generalizability,ethical concerns,and clinical adoption.These challenges emphasize the importance of conducting future research in areas such as multimodal signal analysis and explainable AI.The findings of this review aim to benefit clinicians,healthcare professionals,and society by facilitating better patient outcomes in cognitive healthcare. 展开更多
关键词 Cognitive healthcare Deep learning Wearable sensor Convolutional neural network Recurrent neural network
暂未订购
The Rome consensus:good clinical trials for traditional medicine
8
作者 Junhua Zhang Boli Zhang +26 位作者 Alice J.Fauci Myeong Soo Lee LSusan Wieland Iman Majd Terje Alræk Linda Zhong Sergio Bangrazi Aldo Liguori Jingqing Hu Yanming Xie Jianyuan Tang Zhongqi Yang Paolo Landini Annalisa Bucchi Weian Yuan Kam Wa Chan Filomena Petti Carlo Maria Giovanardi Jialiang He Rui Gao Baohe Wang Yuhong Huang Jia Liu Fang Lu Jianan Guo Pasquale Ricci Bo Pang 《Acupuncture and Herbal Medicine》 2025年第3期271-272,共2页
Traditional Medicine(TM),particularly Traditional Chinese Medicine(TCM),is an indispensable component of the global healthcare system,offering unique insights to modern medical science.Clinical efficacy is the bedrock... Traditional Medicine(TM),particularly Traditional Chinese Medicine(TCM),is an indispensable component of the global healthcare system,offering unique insights to modern medical science.Clinical efficacy is the bedrock for the inheritance and development of TM.To meet the growing demand for high-quality healthcare,it is imperative to integrate TM with modern technology to address the issue of insufficient evidence for the efficacy of TM. 展开更多
关键词 traditional medicine healthcare system traditional chinese medicine tcm traditional medicine tm particularly modern technology clinical trials traditional Chinese medicine clinical efficacy
暂未订购
Phytochemical screening, antioxidant and cytotoxic activity of fruit extracts of Calamus tenuis Roxb
9
作者 Zaki Uddin Ahmed Seheli Sejuti Bithi +3 位作者 Md.Minhazur Rahman Khan Md.Mofazzol Hossain Suriya Sharmin Satyajit Roy Rony 《Journal of Coastal Life Medicine》 2014年第8期645-650,共6页
Objective:To investigate the antioxidant and cytotoxic activity of the fruits of Calamus tenuis Roxb.Methods:The preliminary phytochemical group tests were done,which revealed the presence of alkaloid,tannin,flavonoid... Objective:To investigate the antioxidant and cytotoxic activity of the fruits of Calamus tenuis Roxb.Methods:The preliminary phytochemical group tests were done,which revealed the presence of alkaloid,tannin,flavonoid and steroid.The dried fruit was extracted in soxhlet apparatus using petroleum ether,ethyl acetate and methanol.Antioxidant potential of each extract was evaluated using total phenol content,total flavonoid content,cupric reducing antioxidant capacity,1,1-diphenyl-2-picrylhydrazyl radical scavenging activity,and total antioxidant capacity determinations.Results:The extracts were found to possess moderate to high amounts of phenolic and flavonoid contents.In cupric reducing antioxidant capacity assay the extracts showed moderate reducing power which increases with concentration.Scavenging of 1,1-diphenyl-2-picrylhydrazyl radical was found to rise with concentration with lowest IC_(50)value for methanol extract,which was confirmed by total antioxidant activity test that shows highest(95 mg/g of extract)in ascorbic acid equivalent for methanol extract.In Brine shrimp lethality bioassay the methanol and petroleum ether extracts were found to be toxic to Brine shrimp nauplii,with LC_(50)of 25.53μg/mL and 28.07μg/mL respectively while the LC_(50)of the reference vincristine sulphate was 1.32μg/mL.Ethyl acetate extract was found to be moderately cytotoxic showing LC_(50)of 47.79μg/mL.Conclusions:The results of the present study suggest that the fruits of Calamus tenuis Roxb possess antioxidant and cytotoxic potential.Moreover,phytochemical screening reveals the presence of alkaloid,tannin,flavonoid and steroid,which may be responsible for the observed bioactivities. 展开更多
关键词 Calamus tenuis Roxb Phytochemical screening ANTIOXIDANT CYTOTOXICITY
原文传递
贵州寒武系第二统杷榔组有壳变形虫的新发现 被引量:1
10
作者 尹磊明 孟凡巍 +3 位作者 欧志吉 王凯 陈争鹏 赵元龙 《古生物学报》 CAS CSCD 北大核心 2024年第2期221-232,共12页
有壳变形虫(testate amoebae)的演化历史最早可追溯至新元古代早期,以该时期北美、挪威、澳洲以及我国华北等多地的浅海相碳酸盐岩、页岩中发现的瓶状微体化石(vase-shaped microfossils)为标志。此前认为,显生宙的有壳变形虫最早出现... 有壳变形虫(testate amoebae)的演化历史最早可追溯至新元古代早期,以该时期北美、挪威、澳洲以及我国华北等多地的浅海相碳酸盐岩、页岩中发现的瓶状微体化石(vase-shaped microfossils)为标志。此前认为,显生宙的有壳变形虫最早出现在早泥盆世。长期以来,早古生代的地层中未发现这类原生生物的明确化石证据。本研究通过对岩石样品进行常规孢粉酸泡分析处理和切磨岩石薄片,获取原位保存的化石标本的技术方法,从贵州东部剑河县交榜剖面出露的寒武系杷榔组(第2统第4阶)中获得数枚有壳变形虫(testate amoebae)化石标本。基于标本的显微形态特征,并结合激光拉曼光谱等研究,对原先记述为疑源类的Plagasphaera balangensis和P.sp.A两形态种进行重新认识和描述。由于它们在结构和形态上与一些现生的鳞壳虫目(Euglyphida)有壳变形虫极为相似,因此将先前定为疑源类的Plagasphaera balangensis和P.sp.A两形态属、种名,分别修订为Palaeoassulina balangensis gen.et sp.nov.和?Palaeoassulina sp.A。该发现不仅将显生宙有壳变形虫的原有化石记录从晚古生代泥盆纪向前延伸至寒武纪早期,还为调查研究有壳变形虫的系统演化提供关键的生物化石证据。 展开更多
关键词 有壳变形虫 杷榔组 寒武系 贵州
原文传递
Research trends of clinical studies on acupuncture protocols over the past 20 years:a bibliometric analysis
11
作者 Zhi-Qiang Li Xue-Feng Wang +3 位作者 Heng Yin Feng Cao Yu-Tong Fei Jian-Ping Liu 《Integrative Medicine Discovery》 2024年第28期1-14,共14页
Background:Acupuncture protocols are essential as they guide study design and improve the quality of clinical trial,thus preventing avoid research waste.Given the increasing number of publications on acupuncture proto... Background:Acupuncture protocols are essential as they guide study design and improve the quality of clinical trial,thus preventing avoid research waste.Given the increasing number of publications on acupuncture protocols,this study aimed to assess the publications trends of acupuncture protocols over the past two decades and provided an overview for future research directions.Methods:Publications focusing on acupuncture protocols in clinical settings were retrieved and compiled from the Web of Science Core Collection spanning the period from 2004 to 2023.CiteSpace and Microsoft Excel software were used to analyze the relationship of publication with countries,institutions,authors,co-cited author,journals,references,keywords and other literature aspects.Results:This study analyzed 721 articles encompassing acupuncture protocols.A continuous yet fluctuating growth in publications volume were observed from 2004 to 2023.Notably,China stands at the forefront in contributing to acupuncture protocols,publishing 513 papers and demonstrating a high centrality score of 1.07 in cooperative network.Furthermore,China has fostered close collaborations with the USA and South Korea.Beijing University of Chinese Medicine(89),Zhishun Liu(36)and Trials(306)emerged as the top contributors in terms of institution,author,and journal,respectively.However,inter-institutional and author collaboration was relatively weak.Macpherson H was the most frequently cited author.High-frequency keywords included“randomized controlled trials”,“acupuncture”,“management”,“study protocol”,“quality of life”.Analysis of timeline diagram of keywords indicated that“functional dyspepsia”,“stroke”,“electroacupuncture”,and“colorectal cancer”were the research development trends and focus.Conclusion:Clinical acupuncture protocols have experienced robust development over the past two decades,with current research hotspots focusing on disease management and quality of life,which remain key research concerns.Moreover,we advocate for researchers to publish acupuncture protocols,which remain key research concerns.This approach allows for thorough pre-study planning of methodologies and objectives,enhancing scientific rigor through peer review,thereby laying the foundation for conducting high-quality research. 展开更多
关键词 ACUPUNCTURE PROTOCOL BIBLIOMETRIC HOTSPOTS CiteSpace
暂未订购
Frame Length Dependency for Fundamental Frequency Extraction in Noisy Speech
12
作者 Md. Saifur Rahman Any Chowdury +2 位作者 Nargis Parvin Arpita Saha Moinur Rahman 《Journal of Signal and Information Processing》 2024年第1期1-17,共17页
The fundamental frequency plays a significant part in understanding and perceiving the pitch of a sound. The pitch is a fundamental attribute employed in numerous speech-related works. For fundamental frequency extrac... The fundamental frequency plays a significant part in understanding and perceiving the pitch of a sound. The pitch is a fundamental attribute employed in numerous speech-related works. For fundamental frequency extraction, several algorithms have been developed which one to use relies on the signal’s characteristics and the surrounding noise. Thus, the algorithm’s noise resistance becomes more critical than ever for precise fundamental frequency estimation. Nonetheless, numerous state-of-the-art algorithms face struggles in achieving satisfying outcomes when confronted with speech recordings that are noisy with low signal-to-noise ratio (SNR) values. Also, most of the recent techniques utilize different frame lengths for pitch extraction. From this point of view, This research considers different frame lengths on male and female speech signals for fundamental frequency extraction. Also, analyze the frame length dependency on the speech signal analytically to understand which frame length is more suitable and effective for male and female speech signals specifically. For the validation of our idea, we have utilized the conventional autocorrelation function (ACF), and state-of-the-art method BaNa. This study puts out a potent idea that will work better for speech processing applications in noisy speech. From experimental results, the proposed idea represents which frame length is more appropriate for male and female speech signals in noisy environments. 展开更多
关键词 Pitch Estimation Fundamental Frequency BaNa ACF Frame Length
在线阅读 下载PDF
乌司他丁联合纤支镜在肺部感染致呼吸衰竭机械通气中的应用价值 被引量:14
13
作者 王宁 杨佳佳 +1 位作者 王丹丹 马佩 《实用医学杂志》 CAS 北大核心 2021年第22期2914-2918,共5页
目的分析乌司他丁联合支气管肺泡灌洗(BAL)治疗肺部感染致呼吸衰竭机械通气患者的临床价值。方法将2017年1月至2020年6月在郑州大学第一附属医院ICU治疗的117例肺部感染致呼吸衰竭机械通气患者按治疗方式分观察组(BAL联合乌司他丁治疗,n... 目的分析乌司他丁联合支气管肺泡灌洗(BAL)治疗肺部感染致呼吸衰竭机械通气患者的临床价值。方法将2017年1月至2020年6月在郑州大学第一附属医院ICU治疗的117例肺部感染致呼吸衰竭机械通气患者按治疗方式分观察组(BAL联合乌司他丁治疗,n=58)与对照组(BAL治疗,n=59);比较两组外周血炎症介质水平、肺功能指标、血气分析指标、不良反应及预后情况。结果治疗后两组外周血肿瘤坏死因子(TNF-α)、转化生长因子-β1(TGF-β1)、C反应蛋白(CRP)较治疗前均下降,观察组外周血TNF-α、TGF-β、CRP低于对照组(P<0.05);治疗后两组呼吸峰流速(PTEF)、达峰容积比(VPTEF/VTE)、达峰时间比(TPTEF/TE)、呼出50%潮气量时的流速(TEF50%)/PTEF、呼出25%潮气量时的流速(TEF25%)/PTEF较治疗前上升,观察组PTEF、VPTEF/VTE、TPTEF/TE、TEF50/PTEF、TEF25/PTEF高于对照组(P<0.05);治疗后两组氧合指数(OI)、动脉血氧分压(PaO_(2))上升,动脉血二氧化碳分压(PaCO_(2))下降,观察组OI、PaO_(2)高于对照组,PaCO_(2)低于对照组;两组排痰量、28 d病死率差异无统计学意义(P>0.05),但观察组机械通气时间、住院时间较对照组短(P<0.05)。结论乌司他丁联合BAL治疗肺部感染致呼吸衰竭机械通气患者可有效改善机体局部炎症反应及肺功能,优化血气,值得临床推介。 展开更多
关键词 肺部感染 呼吸衰竭 机械通气 乌司他丁 炎症介质 肺功能
暂未订购
绿色通航视域下过坝船舶预约调度双目标优化研究 被引量:7
14
作者 高攀 刘顺 +1 位作者 赵旭 余浩 《交通运输系统工程与信息》 EI CSCD 北大核心 2022年第5期293-299,336,共8页
针对船舶到达不均衡和供需时空不匹配导致的水利枢纽通航拥堵问题,建立过坝船舶预约的双目标决策模型,优化船舶平均等待时间和到达调整率,探讨两者之间的权衡关系;进一步考虑船舶的失约情形,设计过坝预约的重调度规则。然后,利用非支配... 针对船舶到达不均衡和供需时空不匹配导致的水利枢纽通航拥堵问题,建立过坝船舶预约的双目标决策模型,优化船舶平均等待时间和到达调整率,探讨两者之间的权衡关系;进一步考虑船舶的失约情形,设计过坝预约的重调度规则。然后,利用非支配排序遗传算法的gamultiobj函数求解模型,并探讨预约机制实施前后的碳减排效果。最后,以三峡枢纽为例,验证模型的有效性。结果表明:该模型在平均等待时间和到达调整率的权衡中,得到了多样化的预约调度方案,并通过合理分配预约份额,有序管理船舶到达。同时,与原调度方案相比,理想和失约情形下的预约调度方案,可分别带来27.51 t和20.04 t的最大碳减排量;且重调度策略使到达调整率的均值降低了2.7%,减少了失约的干扰影响。 展开更多
关键词 水路运输 碳减排 非支配排序遗传算法 船舶预约 重调度策略
在线阅读 下载PDF
一种面向高异质性极化SAR图像的等效视数非监督估计方法 被引量:1
15
作者 胡丁晟 仇晓兰 +1 位作者 Stian N.Anfinsen 雷斌 《电子与信息学报》 EI CSCD 北大核心 2017年第10期2287-2293,共7页
等效视数(ENL)是极化SAR多视数据统计模型的重要参数。而一些极化SAR图像的自动化应用中,需要在没有人工干预下实现ENL非监督估计。现有的等效视数非监督估计方法在异质程度较高的图像中就难以得到准确估计结果。针对这一问题,该文提出... 等效视数(ENL)是极化SAR多视数据统计模型的重要参数。而一些极化SAR图像的自动化应用中,需要在没有人工干预下实现ENL非监督估计。现有的等效视数非监督估计方法在异质程度较高的图像中就难以得到准确估计结果。针对这一问题,该文提出一种将混合区域剔除与纹理信息聚类相结合的等效视数非监督估计方法,有效地减弱了地物混合及纹理两类主要异质因素对估计结果的影响。通过仿真数据和不同复杂度的实际图像验证了该方法的有效性。 展开更多
关键词 极化SAR 乘积模型 异质性 等效视数 非监督估计
在线阅读 下载PDF
The influence of physiobiomechanical parameters,technical aspects of shooting,and psychophysiological factors on biathlon performance:A review 被引量:9
16
作者 Marko S.Laaksonen Thomas Finkenzeller +1 位作者 Hans-Christer Holmberg Gerold Sattlecker 《Journal of Sport and Health Science》 SCIE 2018年第4期394-404,共11页
The biathlon,an Olympic sporting discipline that combines cross-country skiing with rifle marksmanship,entails considerable physiological demands,as well as fine motor control while shooting after intense exercise and... The biathlon,an Olympic sporting discipline that combines cross-country skiing with rifle marksmanship,entails considerable physiological demands,as well as fine motor control while shooting after intense exercise and under mental pressure.Although much of our knowledge about cross-country skiing is probably also applicable to the biathlon,carrying the rifle and shooting under stress make this discipline somewhat unique.The present review summarizes and examines the scientific literature related to biathlon performance,with a focus on physiological and biomechanical factors and shooting technique,as well as psychophysiological aspects of shooting performance.We conclude with suggestions for future research designed to extend our knowledge about the biathlon,which is presently quite limited.2018 Published by Elsevier B.V.on behalf of Shanghai University of Sport.This is an open access article under the CC BY-NC-ND license.(http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Cortical activity Gaze behavior Postural balance SKIING TRIGGERING
在线阅读 下载PDF
Associations of accelerometer-determined physical activity and sedentary behavior with sarcopenia and incident falls over 12 months in community-dwelling Swedish older adults 被引量:3
17
作者 David Scott Jonas Johansson +3 位作者 Anoohya Gandham Peter R.Ebeling Peter Nordstrom Anna Nordstrom 《Journal of Sport and Health Science》 SCIE 2021年第5期577-584,共8页
Purpose:This study was aimed to determine associations of accelerometer-determined time and bouts of sedentary behavior,light physical activity(LPA),and moderate-to-vigorous PA(MVPA)with sarcopenia and incident falls ... Purpose:This study was aimed to determine associations of accelerometer-determined time and bouts of sedentary behavior,light physical activity(LPA),and moderate-to-vigorous PA(MVPA)with sarcopenia and incident falls over 12 months.Methods:A total of 3334 Swedish 70-year-olds were assessed for sarcopenia,as defined by the revised definition of the European Working Group on Sarcopenia in Older People.Assessments were based on low scores for appendicular lean mass(dual-energy X-ray absorptiometry),hand grip strength,and the Timed Up and Go test.For 7 days after baseline,total time and total number of bouts(≥10 min of continuous activity at a given intensity)of activity performed at sedentary,LPA,and MVPA intensities were assessed by accelerometer.Incident falls were self-reported 6 months and 12 months after baseline.Results:Only 1.8%of participants had probable or confirmed sarcopenia.After multivariable adjustment for other levels of activity,only greater MVPA time was associated with a decreased likelihood of having low appendicular lean mass,low hand grip strength,and slow Timed Up and Go time as defined by the European Working Group on Sarcopenia in Older People criteria(all p<0.05),and only MVPA time was associated with lower likelihood of probable or confirmed sarcopenia(odds ratio=0.80,95%confidence interval:0.71-0.91 h/week).Similar associations were identified for total number of bouts,with no evidence of threshold effects for longer duration of bouts of MVPA.A total of 14%of participants reported-1 fall,but neither total time nor bouts of activity was associated with incident falls(all p>0.05).Conclusion:Higher amounts of accelerometer-determined MVPA are consistently associated with a decreased likelihood of sarcopenia and its components,regardless of the length of bouts or amounts of sedentary behavior. 展开更多
关键词 ACCELEROMETER FALLS Older adults Physical activity SARCOPENIA
在线阅读 下载PDF
Do patients with gastroesophageal reflux disease and somatoform tendencies benefit from antireflux surgery? 被引量:2
18
作者 Hans Friedrich Fuchs Benjamin Babic +3 位作者 Karl-Hermann Fuchs Wolfram Breithaupt Gabor Varga Frauke Musial 《World Journal of Gastroenterology》 SCIE CAS 2019年第3期388-397,共10页
BACKGROUND The clinical presentation of gastroesophageal reflux disease(GERD) shows a large symptom variation also in different intensities among patients. As several studies have shown, there is a large overlap in th... BACKGROUND The clinical presentation of gastroesophageal reflux disease(GERD) shows a large symptom variation also in different intensities among patients. As several studies have shown, there is a large overlap in the symptomatic spectrum between proven GERD and other disorders such as dyspepsia, functional heartburn and/or somatoform disorders.AIM To prospectively evaluate the GERD patients with and without somatoform disorders before and after laparoscopic antireflux surgery.METHODS In a tertiary referral center for foregut surgery over a period of 3 years patients with GERD, qualifying for the indication of laparoscopic antireflux surgery, were investigated prospectively regarding their symptomatic spectrum in order to identify GERD and associated somatoform disorders. Assessment of symptoms was performed by an instrument for the evaluation of somatoform disorders[Somatoform Symptom Index(SSI) > 17]. Quality of life was evaluated by Gastrointestinal Quality of Life Index(GIQLI).RESULTS In 123 patients an indication for laparoscopic antireflux surgery was established and in 43 patients further medical therapy was suggested. The portion of somatoform tendencies in the total patient population was 20.48%(34 patients).Patients with a positive SSI had a preoperative GIQLI of 77(32-111). Patients with a normal SSI had a GIQLI of 105(29-140)(P < 0.0001). In patients with GERD the quality of life could be normalized from preoperative reduced values of GIQLI102(47-140) to postoperative values of 117(44-144). In patients with GERD and somatoform disorders, the GIQLI was improved from preoperative GIQLI 75(47-111) to postoperative 95(44-122)(P < 0.0043).CONCLUSION Patients with GERD and associated somatoform disorders have significantly worse levels of quality of life. The latter patients can also benefit from laparoscopic fundoplication, however they will not reach a normal level. 展开更多
关键词 GASTROESOPHAGEAL REFLUX DISEASE ANTIREFLUX surgery Laparoscopic fundoplication SOMATIZATION GASTROESOPHAGEAL REFLUX DISEASE symptoms
暂未订购
Reliability of the MPPT Control on the Energy Parameters of a Photovoltaic Generator 被引量:1
19
作者 Batassou Guilzia Jeannot Mandeng Jean Jacques Mane Mane Jeannot 《World Journal of Engineering and Technology》 2020年第3期537-550,共14页
This article describes a technique that allows a photovoltaic (PV) production unit to obtain the maximum power at all times. Here, we use the MPPT control via fuzzy logic on a DC/DC boost-type converter. In order to a... This article describes a technique that allows a photovoltaic (PV) production unit to obtain the maximum power at all times. Here, we use the MPPT control via fuzzy logic on a DC/DC boost-type converter. In order to achieve our goals, we first proceeded to model a PV panel. The resulting model offers the possibility to better account for the influence of different physical quantities such as temperature, irradiation, series resistance, shunt resistance and diode saturation current. Thus, the maximum power to be provided by the PV system is acquired by fuzzification and defuzzification of the input and output variables of the converter. Subsequently, a virtual model of an 800 Watt PV prototype is implemented in the Matlab environment. The simulation results obtained and presented, show the feasibility and efficiency of the proposed technology. Indeed, for a disturbance caused by a variation in brightness, our system guarantees the maximum stable power after 1.4</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">s. While for a load variation, the maximum power is continuous. 展开更多
关键词 Low Voltage Photovoltaic System Fuzzy Logic Maximum Power Point
在线阅读 下载PDF
Pacing and predictors of performance during cross-country skiing races:A systematic review 被引量:8
20
作者 Thomas Stögg Barbara Peegrini Hans-Christer Homberg 《Journal of Sport and Health Science》 SCIE 2018年第4期381-393,共13页
Background:Cross-country skiing(XCS)racing,a popular international winter sport,is complex and challenging from physical,technical,and tactical perspectives.Despite the vast amount of research focusing on this sport,n... Background:Cross-country skiing(XCS)racing,a popular international winter sport,is complex and challenging from physical,technical,and tactical perspectives.Despite the vast amount of research focusing on this sport,no review has yet addressed the pacing strategies of elite XCS racers or the factors that influence their performance.The aim was to review the scientific literature in an attempt to determine the effects of pacing strategy on the performance of elite XCS racers.Methods:Four electronic databases were searched using relevant subject headings and keywords.Only original research articles published in peerreviewed journals and the English language and addressing performance,biomechanics,physiology,and anthropometry of XCS racers were reviewed.Results:All 27 included articles applied correlative designs to study the effectiveness of different pacing strategies.None of the articles involved the use of an experimental design.Furthermore,potential changes in external conditions(e.g.,weather,ski properties)were not taken into consideration.A comparable number of studies focused on the skating or classical technique.In most cases,positive pacing was observed,with certain indications that higher-level athletes and those with more endurance and strength utilized a more even pacing strategy.The ability to achieve and maintain a long cycle length on all types of terrain was an important determinant of performance in all of the included studies,which was not the case for cycle rate.In general,uphill performance was closely related to overall race performance,with uphill performance being most closely correlated to the success of female skiers and performance on flat terrain being more important for male skiers.Moreover,pacing was coupled to the selection and distribution of technique during a race,with faster skiers employing more double poling and kick double poling,less diagonal stride,and more V2(double dance)than V1(single dance)skating across a race.Conclusion:We propose that skiers at all levels can improve their performance with more specific training in techniques(i.e.,maintaining long cycles without compromising cycle rate and selecting appropriate techniques)in combination with training for endurance and more strength.Furthermore,we would advise less experienced skiers and/or those with lower levels of performance to apply a more even pacing strategy rather than a positive one(i.e.,starting the race too fast).2018 Published by Elsevier B.V.on behalf of Shanghai University of Sport.This is an open access article under the CC BY-NC-ND license.(http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Classic style Competition Cycle characteristics Positive pacing SKATING
在线阅读 下载PDF
上一页 1 2 4 下一页 到第
使用帮助 返回顶部