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Watchman FLX封堵器的最新研究进展 被引量:1
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作者 陆祎洁 王永利 陈蕊蕊 《心脏杂志》 CAS 2024年第4期466-471,491,共7页
左心耳封堵手术已经成为口服抗凝药物禁忌症或者不能长期耐受口服抗凝药物的非瓣膜性房颤患者的替代治疗方案。尽管左心耳封堵手术已经相当成熟,但住院期间并发症(心包积液和心脏压塞、全身栓塞、封堵器脱落)和术后随访封堵器相关血栓,... 左心耳封堵手术已经成为口服抗凝药物禁忌症或者不能长期耐受口服抗凝药物的非瓣膜性房颤患者的替代治疗方案。尽管左心耳封堵手术已经相当成熟,但住院期间并发症(心包积液和心脏压塞、全身栓塞、封堵器脱落)和术后随访封堵器相关血栓,器械残余漏等问题依然亟待解决。目前临床常用的左心耳封堵器主要有Watchman2.5^(TM)和Amplatzer Amulet两种。受限于封堵器本身结构设计,对于少数左心耳解剖结构复杂的患者,现有封堵器应用受限。Watchman FLX是新一代的左心耳封堵器,对比Watchman 2.5^(TM)有很多结构上的优化,在保证有效性与安全性的基础上,器械封堵效率更高,并发症更少。本文将对Watchman FLX的最新研究成果进行综述。 展开更多
关键词 watchman FLX 左心耳封堵 非瓣膜性房颤
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非瓣膜性心房颤动患者DSA指导下极简式经皮植入WATCHMAN FLX左心耳封堵器的效果观察
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作者 费晓红 孙一钧 +5 位作者 王彬浩 傅国华 丰明俊 郁一波 杜先锋 储慧民 《心电与循环》 2024年第4期354-357,共4页
目的 观察数字减影血管造影(DSA)指导下极简式经皮植入WATCHMAN FLX左心耳封堵器的临床效果。方法2022年6月至2024年1月在宁波大学附属第一医院接受DSA指导下极简式经皮植入WATCHMAN FLX左心耳封堵器的非瓣膜性心房颤动(下称房颤)患者15... 目的 观察数字减影血管造影(DSA)指导下极简式经皮植入WATCHMAN FLX左心耳封堵器的临床效果。方法2022年6月至2024年1月在宁波大学附属第一医院接受DSA指导下极简式经皮植入WATCHMAN FLX左心耳封堵器的非瓣膜性心房颤动(下称房颤)患者15例,记录手术情况和随访情况。结果 患者手术时间、X线曝光时间分别为(41.3±10.3)、(7.7±2.4)min。术中DSA检查提示左心耳口部直径最大值为(24.0±4.5)mm,左心耳深度最大值为(27.4±5.4)mm。14例患者封堵器一次性成功释放,未出现封堵器尺寸调整情况,封堵器尺寸(28.5±5.2)mm。封堵后DSA显示左心耳完全封堵,未见明显残余分流。围术期均未发生血栓栓塞事件、大出血事件、心包积液等并发症;1例(6.7%)患者出现穿刺点淤斑,1周后自行吸收。术后经食管超声心动图复查均未发现封堵器表面血栓,3例(20.0%)患者存在<3 mm残余分流。随访310(163,631)d,随访期间患者均未出现血栓栓塞事件、大出血事件。结论 非瓣膜性房颤患者DSA指导下极简式经皮植入WATCHMAN FLX左心耳封堵器是安全可行的。 展开更多
关键词 心房颤动 左心耳封堵术 极简式 watchman FLX封堵器
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Higher Grain-Filling Rate in Inferior Spikelets of Tolerant Rice Genotype Offset Grain Yield Loss under Post-Anthesis High Night Temperatures
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作者 Nitin SHARMA Bhupinder SINGH +6 位作者 Subbaiyan Gopala KRISHNAN Haritha BOLLINEDI Pranab Kumar MANDAL Milan Kumar LAL Prakash Kumar JHA P.V.Vara PRASAD Anjali ANAND 《Rice science》 SCIE CSCD 2024年第5期572-586,I0059-I0061,共18页
Increased nighttime respiratory losses decrease the amount of photoassimilates available for plant growth and yield. We hypothesized that the increased respiratory carbon loss under high night temperatures(HNT) could ... Increased nighttime respiratory losses decrease the amount of photoassimilates available for plant growth and yield. We hypothesized that the increased respiratory carbon loss under high night temperatures(HNT) could be compensated for by increased photosynthesis during the day following HNT exposure. Two rice genotypes, Vandana(HNT-sensitive) and Nagina 22(HNT-tolerant), were exposed to HNT(4 ℃ above the control) from flowering to physiological maturity. They were assessed for alterations in the carbon balance of the source(flag leaf) and its subsequent impact on grain filling dynamics and the quality of spatially differentiated sinks(superior and inferior spikelets). Both genotypes exhibited significantly higher night respiration rates. However, only Nagina 22 compensated for the high respiration rates with an increased photosynthetic rate, resulting in a steady production of total dry matter under HNT. Nagina 22 also recorded a higher grain-filling rate, particularly at 5 and 10 d after flowering, with 1.5- and 4.0-fold increases in the translocation of ^(14)C sugars to the superior and inferior spikelets, respectively. The ratio of photosynthetic rate to respiratory rate on a leaf area basis was negatively correlated with spikelet sterility, resulting in a higher filled spikelet number and grain weight per plant, particularly for inferior grains in Nagina 22. Grain quality parameters such as head rice recovery, high-density grains, and gelatinization temperature were maintained in Nagina 22. An increase in the rheological properties of rice flour starch in Nagina 22 under HNT indicated the stability of starch and its ability to reorganize during the cooling process of product formation. Thus, our study showed that sink adjustments between superior and inferior spikelets favored the growth of inferior spikelets, which helped to offset the reduction in grain weight under HNT in the tolerant genotype Nagina 22. 展开更多
关键词 high night temperature inferior grain pasting property radiolabeled sugar superior grain
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ED-Ged:Nighttime Image Semantic Segmentation Based on Enhanced Detail and Bidirectional Guidance
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作者 Xiaoli Yuan Jianxun Zhang +1 位作者 Xuejie Wang Zhuhong Chu 《Computers, Materials & Continua》 SCIE EI 2024年第8期2443-2462,共20页
Semantic segmentation of driving scene images is crucial for autonomous driving.While deep learning technology has significantly improved daytime image semantic segmentation,nighttime images pose challenges due to fac... Semantic segmentation of driving scene images is crucial for autonomous driving.While deep learning technology has significantly improved daytime image semantic segmentation,nighttime images pose challenges due to factors like poor lighting and overexposure,making it difficult to recognize small objects.To address this,we propose an Image Adaptive Enhancement(IAEN)module comprising a parameter predictor(Edip),multiple image processing filters(Mdif),and a Detail Processing Module(DPM).Edip combines image processing filters to predict parameters like exposure and hue,optimizing image quality.We adopt a novel image encoder to enhance parameter prediction accuracy by enabling Edip to handle features at different scales.DPM strengthens overlooked image details,extending the IAEN module’s functionality.After the segmentation network,we integrate a Depth Guided Filter(DGF)to refine segmentation outputs.The entire network is trained end-to-end,with segmentation results guiding parameter prediction optimization,promoting self-learning and network improvement.This lightweight and efficient network architecture is particularly suitable for addressing challenges in nighttime image segmentation.Extensive experiments validate significant performance improvements of our approach on the ACDC-night and Nightcity datasets. 展开更多
关键词 night driving semantic segmentation nighttime image processing adverse illumination differentiable filters
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Unveiling the challenges encountered by newly graduated nurses during night shifts:A descriptive qualitative study
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作者 Naomi Kisanuki Miyuki Takase Masako Yamamoto 《International Journal of Nursing Sciences》 CSCD 2024年第4期447-456,共10页
Objectives:Newly graduated nurses commence night shifts during a phase of heightened vulnerability to reality shock,exacerbating the challenges faced by these graduates.Therefore,this study aimed to identify the chall... Objectives:Newly graduated nurses commence night shifts during a phase of heightened vulnerability to reality shock,exacerbating the challenges faced by these graduates.Therefore,this study aimed to identify the challenges experienced by newly graduated nurses when undertaking night shifts in order to help identify a strategy for supporting their adaptation to these shifts.Methods:Semi-structured personal interviews were used to collect data.Fifteen newly graduated nurses were selected to participate in the study by purposive sampling method from November 2021 to March 2022 in one of four general hospitals situated in the southwestern region of Japan.Semi-structured interviews were analyzed by using thematic analysis.Results:The analysis revealedfive central themes and nine subthemes:challenges in task efficiency(task organization challenges,challenges in time-constrained task performance),challenges in responding to patients’changing conditions(challenges in responding to patients’irregular conditions,challenges in responding to nighttime changes in patients’behaviors),challenges in independent practice(challenges in engaging in independent nursing practice,challenges in dealing with unexpected events),challenges in establishing collaborative relationships(challenges in working closely with other staff,challenges in establishing collaborative relationships during night shifts with limited resources),challenges in adapting to shift work(challenges in managing physical conditions for shift work).Conclusions:Newly graduated nurses often encounter challenges in performing their tasks during the transition period.When working night shifts,they face additional hurdles unique to nocturnal duties.Thefindings underscore the necessity for these graduates to develop night shift-specific readiness to effectively navigate the demands inherent in such work schedules. 展开更多
关键词 CHALLENGE Newly graduated nurses Patient care management Qualitative research Shift work schedule night shifts
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High-quality Development of the Pearl River Night Tour in the Context of Deep Integration of Culture and Tourism
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作者 Juan JIANG Lianrong PANG 《Meteorological and Environmental Research》 2024年第1期38-45,共8页
Urban night tourism is a new form of urban tourism development and an important driving force for the prosperity of urban night economy.As the most prestigious business card among many night tour projects in Guangzhou... Urban night tourism is a new form of urban tourism development and an important driving force for the prosperity of urban night economy.As the most prestigious business card among many night tour projects in Guangzhou,the Pearl River water night tour has contributed to the development of Guangzhou s night economy,which cannot be underestimated.However,in the process of rapid development,there are also problems such as diversified operators,insufficient integration of intangible cultural elements,excessive commercial attributes,issues of tourism facilities and service facilities.Under the new stage of integrated development of culture and tourism,how to use mutual promotion of culture and tourism in the Pearl River night tour to seek innovative paths for high-quality development in the future is the main problem expected to be solved in this paper.Therefore,based on the perspective of culture and tourism integration,this paper analyzes the general situation and development status of the Pearl River night tour,and proposes five development strategies:the overall planning of culture and tourism integration,the deep integration of intangible cultural elements,the balance of commercial attributes and tourism attributes,the high integration of culture,business,tourism and education,and the creation of tourism atmosphere,in order to provide inspiration for the healthy,orderly and high-quality development of the Pearl River night tour. 展开更多
关键词 Integration of culture and tourism The Pearl River night tour High-quality development Intangible cultural elements
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Strategies for Applying LED Lights in Night Space Lighting for Bridges
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作者 Yingling Dai Qinghua Zhao 《Journal of World Architecture》 2024年第3期57-62,共6页
LED lights have been widely used in urban night space lighting in recent years as they are small,energy-saving,and efficient.This article explores the use of LEDs in bridge night space lighting and their application s... LED lights have been widely used in urban night space lighting in recent years as they are small,energy-saving,and efficient.This article explores the use of LEDs in bridge night space lighting and their application strategies.The aim is to offer valuable insights and references for urban planners and bridge lighting designers in China.By advancing the application of LED technology in bridge night lighting,the goal is to enhance the city’s nighttime ambiance,making the bridge an iconic landmark and a defining feature of the city. 展开更多
关键词 Bridge night space lighting LED application Color band and gradient Artistic value Online publication:July 11 2024
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WATCHMAN FLX左心耳封堵器预防房颤患者卒中的国内应用初步分析
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作者 张晓春 侯士强 +6 位作者 李伟 陈莎莎 李明飞 张蕾 潘文志 周达新 葛均波 《复旦学报(医学版)》 CAS CSCD 北大核心 2023年第3期433-438,446,共7页
目的探讨WATCHMAN FLX左心耳封堵器首次在中国内地应用的安全性、有效性以及手术经验。方法筛选2022年5月就诊于复旦大学附属中山医院心内科的非瓣膜性房颤患者。术前完善心超和CT评估,在经食道超声心动图和数字减影血管造影指导下使用W... 目的探讨WATCHMAN FLX左心耳封堵器首次在中国内地应用的安全性、有效性以及手术经验。方法筛选2022年5月就诊于复旦大学附属中山医院心内科的非瓣膜性房颤患者。术前完善心超和CT评估,在经食道超声心动图和数字减影血管造影指导下使用WATCHMAN FLX系统完成经导管左心耳封堵术(transcatheter left atrial appendage occlusion,LAAO),评估手术安全性和封堵即刻有效性,并总结手术经验。结果此封堵器首次应用于中国内地共完成4例手术,其中1例患者行单纯LAAO,其余3例患者行房颤射频消融联合LAAO的“一站式”手术。所有患者均无心包积液、封堵器移位、封堵器脱落、操作相关栓塞、出血、急性器械相关血栓和穿刺部位并发症等不良事件发生。手术即刻封堵成功率为100%,其中3例无任何残余分流,1例有1 mm残余分流。封堵器展开采用FLX BALL的两种新方式:2例采用退鞘法,2例采用推进法。压缩比在13%~28%,封堵器均未露肩。结论WATCHMAN FLX左心耳封堵器有较高的安全性和有效性。 展开更多
关键词 左心耳封堵术(LAAO) watchman FLX左心耳封堵器 心房颤动 操作经验
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Short-term night lighting disrupts lipid and glucose metabolism in Zebra Finches:Implication for urban stopover birds
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作者 Na Zhu Jing Shang Shuping Zhang 《Avian Research》 SCIE CSCD 2023年第4期663-670,共8页
Night lighting has been shown to affect wild animals.To date,the effects of night lighting on the metabolic homeostasis of birds that spend short time in urban environments remain unclear.Using model bird species Zebr... Night lighting has been shown to affect wild animals.To date,the effects of night lighting on the metabolic homeostasis of birds that spend short time in urban environments remain unclear.Using model bird species Zebra Finch(Taeniopygia guttata),we investigated the effects of short-term night lighting on liver transcriptome,blood glucose,triglyceride,and thyroxine(T4 and T3)levels in birds exposed to two different night lighting duration periods(three days and six days).After three days of night lighting exposure,the expression of genes involved in fat synthesis in the liver was upregulated while the expression of genes involved in fatty acid oxidation and triglyceride decomposition was downregulated.There was also a reduction in blood triglyceride,glucose,and T3 concentrations.However,after six days of night lighting,the expression of genes associated with fatty acid decomposition and hyperglycemia in the liver was upregulated,while the expression of genes involved in fat synthesis was downregulated.Simultaneously,blood glucose levels and T3 concentration increased.These findings indicate that short-term exposure to night lighting can disrupt the lipid and glucose metabolism of small passerine birds,and longer stopovers in urban area with intense night lighting may cause birds to consume more lipid energy. 展开更多
关键词 BIRDS Glucose LIPID Metabolism night lighting SHORT-TERM
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High-quality Development Path of Night Tourism in Guangzhou:A Case Study of Firefly Night Tour
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作者 JIANG Juan TANG Wei ZHU Yanqing 《Journal of Landscape Research》 2023年第5期89-93,97,共6页
Night tourism often involves a large number of lighting facilities,which consume a large amount of energy.Therefore,one of the unique low energy consumption natural ecological tourism activities—firefly night tour ha... Night tourism often involves a large number of lighting facilities,which consume a large amount of energy.Therefore,one of the unique low energy consumption natural ecological tourism activities—firefly night tour has attracted attention and become an important breakthrough point for night tourism in tourist destinations.In this paper,Guangzhou firefly night tour project is taken as the research object.Based on the comprehensive economic,environmental,and socio-cultural benefits brought by the development of firefly night tour,the resources distribution,current development status,and existing problems of firefly night tour in Guangzhou are analyzed,and its high-quality development paths are proposed from three levels:government,industry,and tourist.The aim is to explore a new model for the economic development of Guangzhou night tour,boosting the transformation and upgrading of the night tourism economy,while also providing reference ideas and value for the development of night tourism economy in other tourist destinations. 展开更多
关键词 night tourism Firefly night tour GUANGZHOU High-quality development
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Night Economy Glows with New Vitality
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作者 Leo Zhang 《China's Foreign Trade》 2023年第4期57-60,共4页
According to data from ii-Media Research,China’s night economy has grown rapidly since 2016.By the end of 2020,the scale of China’s night economy had exceeded RMB 30 trillion,an increase of 5.0%over the same period ... According to data from ii-Media Research,China’s night economy has grown rapidly since 2016.By the end of 2020,the scale of China’s night economy had exceeded RMB 30 trillion,an increase of 5.0%over the same period of last year,and it is expected to exceed RMB 48 trillion in 2023.According to the latest survey data of the Ocean Engine City Institute in 2023,more than 60%of respondents will go out for activities or consumption at night,among which citizens in high-speed cities have a higher preference for going out at night because of the relatively perfect urban infrastructure. 展开更多
关键词 ECONOMY PERFECT night
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Paper Analysis of the WATCHMAN on the Reduction of Stroke Compared to Anticoagulants: A Systematic Review of the Literature
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作者 Christopher Miller Rawan Sharari +3 位作者 Munira Ali Jonathan Omana Mirjana Milutinovic Aleksandar Dusic 《Open Journal of Internal Medicine》 2023年第3期225-245,共21页
Objective: Anticoagulants have been approved and used for decades as highly effective blood thinners. The objective of this study is to analyze the clinical trials in order to determine if the Watchman reduces the ris... Objective: Anticoagulants have been approved and used for decades as highly effective blood thinners. The objective of this study is to analyze the clinical trials in order to determine if the Watchman reduces the risk of stroke in patients with atrial fibrillation compared to those prescribed the traditional anticoagulants. This will contribute to the current body of knowledge and possibly provide beneficial clinical guidance with respect to providing an alternative option for those suffering from non-valvular Atrial fibrillation. Methods: A systematic literature search through the Saint James School of Medicine library resources as well as PubMed, Medscape, Google Scholar was conducted. Studies were included if the literature examined the comparison between the Watchman device and four specific anticoagulants (Xarelto, Eliquis, Pradaxa, and Warfarin) in association with reduction of risks of strokes in an atrial fibrillation population. The study includes a qualitative sub-analysis to explore additional clinical aspects that may affect risk of stroke and response of treatment. Results: Outcomes were significant for similar stroke occurrence, when compared to published clinical trials. Alternatively, there was a significant reduction in risk of bleeding and all-cause mortality in the Watchman™ device compared to traditional NOACs and warfarin. While examining the studies and trials, overall, the Watchman™ device offers a better long-term outcome therapy for non-valvular atrial fibrillation populations who are not possibilities for extended anticoagulation. The studies used for analysis examining the dosage found higher fatality with increased use of NOACs and more hospitalizations with decreased use. Conclusion: From the presented data, it is safe to say that the Watchman™ device is a viable and effective alternative for stroke prophylaxis in certain patient populations. Compared to traditional anticoagulant therapies for non-valvular atrial fibrillation, these studies suggest that the Watchman™ device can reduce bleeding time and, in most cases, the risk of stroke is less than or equal to traditional anti-coagulants. 展开更多
关键词 watchman stroke risk reduction ANTICOAGULATION
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Single-image night haze removal based on color channel transfer and estimation of spatial variation in atmospheric light
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作者 Shu-yun Liu Qun Hao +6 位作者 Yu-tong Zhang Feng Gao Hai-ping Song Yu-tong Jiang Ying-sheng Wang Xiao-ying Cui Kun Gao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第7期134-151,共18页
The visible-light imaging system used in military equipment is often subjected to severe weather conditions, such as fog, haze, and smoke, under complex lighting conditions at night that significantly degrade the acqu... The visible-light imaging system used in military equipment is often subjected to severe weather conditions, such as fog, haze, and smoke, under complex lighting conditions at night that significantly degrade the acquired images. Currently available image defogging methods are mostly suitable for environments with natural light in the daytime, but the clarity of images captured under complex lighting conditions and spatial changes in the presence of fog at night is not satisfactory. This study proposes an algorithm to remove night fog from single images based on an analysis of the statistical characteristics of images in scenes involving night fog. Color channel transfer is designed to compensate for the high attenuation channel of foggy images acquired at night. The distribution of transmittance is estimated by the deep convolutional network DehazeNet, and the spatial variation of atmospheric light is estimated in a point-by-point manner according to the maximum reflection prior to recover the clear image. The results of experiments show that the proposed method can compensate for the high attenuation channel of foggy images at night, remove the effect of glow from a multi-color and non-uniform ambient source of light, and improve the adaptability and visual effect of the removal of night fog from images compared with the conventional method. 展开更多
关键词 Dehazing image captured at night Chromaticity fusion correction Color channel transfer Spatial change-based atmospheric light ESTIMATION DehazeNet
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Bonfire Night
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作者 《疯狂英语(初中天地)》 2023年第11期28-29,共2页
In the UK,Bonfire Night or Guy Fawkes Night is celebrated on 5 November and the night skies are filled with colour.It’s a special day in honour of a historic event.
关键词 FILLED night night
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Night Vision Object Tracking System Using Correlation Aware LSTM-Based Modified Yolo Algorithm
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作者 R.Anandha Murugan B.Sathyabama 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期353-368,共16页
Improved picture quality is critical to the effectiveness of object recog-nition and tracking.The consistency of those photos is impacted by night-video systems because the contrast between high-profile items and diffe... Improved picture quality is critical to the effectiveness of object recog-nition and tracking.The consistency of those photos is impacted by night-video systems because the contrast between high-profile items and different atmospheric conditions,such as mist,fog,dust etc.The pictures then shift in intensity,colour,polarity and consistency.A general challenge for computer vision analyses lies in the horrid appearance of night images in arbitrary illumination and ambient envir-onments.In recent years,target recognition techniques focused on deep learning and machine learning have become standard algorithms for object detection with the exponential growth of computer performance capabilities.However,the iden-tification of objects in the night world also poses further problems because of the distorted backdrop and dim light.The Correlation aware LSTM based YOLO(You Look Only Once)classifier method for exact object recognition and deter-mining its properties under night vision was a major inspiration for this work.In order to create virtual target sets similar to daily environments,we employ night images as inputs;and to obtain high enhanced image using histogram based enhancement and iterative wienerfilter for removing the noise in the image.The process of the feature extraction and feature selection was done for electing the potential features using the Adaptive internal linear embedding(AILE)and uplift linear discriminant analysis(ULDA).The region of interest mask can be segmen-ted using the Recurrent-Phase Level set Segmentation.Finally,we use deep con-volution feature fusion and region of interest pooling to integrate the presently extremely sophisticated quicker Long short term memory based(LSTM)with YOLO method for object tracking system.A range of experimentalfindings demonstrate that our technique achieves high average accuracy with a precision of 99.7%for object detection of SSAN datasets that is considerably more than that of the other standard object detection mechanism.Our approach may therefore satisfy the true demands of night scene target detection applications.We very much believe that our method will help future research. 展开更多
关键词 Object monitoring night vision image SSAN dataset adaptive internal linear embedding uplift linear discriminant analysis recurrent-phase level set segmentation correlation aware LSTM based yolo classifier algorithm
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数字经济发展与城市收缩——来自夜间灯光数据的证据 被引量:1
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作者 汤凯 刘晓康 《管理学刊》 北大核心 2024年第2期16-33,共18页
数字经济正成为社会经济发展的新动能,它对于抑制城市收缩、促进城市协调发展具有深远影响。利用2011—2021年夜间灯光数据,识别城市收缩,并考察数字经济发展对城市收缩的影响。研究发现,数字经济发展可以显著抑制城市收缩;数字经济发... 数字经济正成为社会经济发展的新动能,它对于抑制城市收缩、促进城市协调发展具有深远影响。利用2011—2021年夜间灯光数据,识别城市收缩,并考察数字经济发展对城市收缩的影响。研究发现,数字经济发展可以显著抑制城市收缩;数字经济发展抑制城市收缩的效应在收缩型城市以及市场化水平低、教育水平低的地区表现得更为明显;城市收入差距、产业结构升级、城市创新创业是数字经济发展抑制城市收缩的重要渠道,加强网络基础设施建设会更有利于数字经济抑制城市严重收缩。进一步研究发现,数字经济发展对城市收缩的影响具有门槛效应,即当数字经济发展达到一定水平后,它对城市收缩的抑制作用才会显现,同时抑制作用具有边际报酬递增的后发性优势。本研究有助于揭示数字经济发展影响城市收缩的作用机制,对于如何利用数字经济有效抑制城市收缩提供了经验支持。 展开更多
关键词 数字经济 城市收缩 夜间灯光数据 影响机制 门槛效应
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基于夜游行为特征的夜游产品优化策略研究——以马鞍山市为例
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作者 包曾婷 吴桐 张淑萍 《安徽冶金科技职业学院学报》 2024年第2期64-66,共3页
文章选取马鞍山市若干个典型地点,对本地居民及外地游客的夜游行为特征进行调查,继而提出夜游产品优化策略:打造文化内涵丰富的特色街巷,优化夜间旅游环境设施,提升夜间旅游服务质量,细分夜间旅游产品市场,以期实现马鞍山夜游市场的可... 文章选取马鞍山市若干个典型地点,对本地居民及外地游客的夜游行为特征进行调查,继而提出夜游产品优化策略:打造文化内涵丰富的特色街巷,优化夜间旅游环境设施,提升夜间旅游服务质量,细分夜间旅游产品市场,以期实现马鞍山夜游市场的可持续发展。 展开更多
关键词 夜游行为特征 夜游产品 夜间经济 优化策略
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以提升患者就医体验为导向的中医药特色夜门诊实践探索
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作者 唐娅琴 边雪梅 +2 位作者 王亚屏 金露梦 孙华琴 《中国医院》 北大核心 2024年第5期92-94,共3页
满足不同就医人群的需求,提供夜间诊疗服务,是改善患者就医体验的重要途径之一。夜门诊的开设有利于医院科学合理调整门诊空间,整合有限的医疗资源。为了提升患者就医体验,保障患者医疗安全,夜门诊开设需要优化医护技等人员的合理配置,... 满足不同就医人群的需求,提供夜间诊疗服务,是改善患者就医体验的重要途径之一。夜门诊的开设有利于医院科学合理调整门诊空间,整合有限的医疗资源。为了提升患者就医体验,保障患者医疗安全,夜门诊开设需要优化医护技等人员的合理配置,加强医院多部门间的配合联动。浙江省中医院通过前期调研,结合中医医院特色、特长,开设具有中医药特色的夜门诊后,门诊运行效率进一步提高,医疗服务质量得到持续改进,得到患者的一致好评。 展开更多
关键词 就医体验 中医药特色 夜门诊
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四川盆地西部边缘不同落区暴雨的气象场差异及夜雨浅析
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作者 杨康权 卢萍 《大气科学》 CSCD 北大核心 2024年第5期1783-1795,共13页
本文基于2015~2018年四川盆地西部边缘出现的典型暴雨个例,以落区为依据进行了统计分类,着重分析了不同空间分布特征暴雨的环境场条件,并从四川盆地夏季大气日变化特征角度来探讨了该区域夜雨频发的原因。研究表明:(1)受四川盆地西部边... 本文基于2015~2018年四川盆地西部边缘出现的典型暴雨个例,以落区为依据进行了统计分类,着重分析了不同空间分布特征暴雨的环境场条件,并从四川盆地夏季大气日变化特征角度来探讨了该区域夜雨频发的原因。研究表明:(1)受四川盆地西部边缘高大陡峭地形影响,盆地西部中低层大气温湿条件好,暖湿东南气流在此遇大地形产生迎风辐合抬升,易发生强降水。当暴雨发生在整个盆西(西部型)时,整个盆地西部的湿度非常大,东南风较强;当暴雨发生在盆地西北部(西北型)时,中低层东南风最强,动力作用最显著;当暴雨发生在盆地西南部(西南型)时,大多伴随有偏北风进入盆地,存在明显的南北风切变辐合。水汽散度通量对四川盆地西部暴雨强度和落区具有较好的指示意义。(2)对流有效位能、相对湿度、假相当位温、中低层风场以及散度这些热力和动力变量的日变化特征,都表明了四川盆地西部降水易发生在夜间。 展开更多
关键词 四川盆地 暴雨落区 夜雨 日变化
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荒漠化矿区土壤碳排放高光谱遥感反演
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作者 刘英 刘宇 +3 位作者 岳辉 毕银丽 彭苏萍 贾羽豪 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第10期2840-2849,共10页
随着我国“碳达峰、碳中和”政策的提出,矿区碳排放成为关注焦点,然而目前缺少矿区土壤碳排放高光谱遥感探测的有效方法。基于矿区实测土壤样品,将6种光谱数学变换方法(R、■、Log(1/R)、1st、MSC、SNV)与光谱特征筛选方法(CC-SPA)相结... 随着我国“碳达峰、碳中和”政策的提出,矿区碳排放成为关注焦点,然而目前缺少矿区土壤碳排放高光谱遥感探测的有效方法。基于矿区实测土壤样品,将6种光谱数学变换方法(R、■、Log(1/R)、1st、MSC、SNV)与光谱特征筛选方法(CC-SPA)相结合,探究新疆红沙泉露天煤矿不同土地利用类型土壤碳排放的高光谱响应特征;结合土壤温度(ST)、土壤湿度(SM)及6种光谱指数(NDVI、RVI、NGLI、SMMI、SI-T、ATI),利用偏最小二乘(PLSR)、支持向量机(SVM)、随机森林(RF)、遗传优化神经网络(GA-BP)算法得到土壤碳排放最优遥感反演模型。主要结论如下:(1)自然条件下非采矿影响区土壤反射率明显高于采矿影响区,其中南线受煤炭开采影响最大,反射率最低,证明采矿活动对矿区土壤产生了影响;(2)光谱特征筛选方面,基于相关系数-连续投影算法(CC-SPA)提取的碳排放特征波段数远小于单一方法,且筛选结果呈现聚集式分布,主要集中于1600~2200 nm波长范围内,白天特征波段数远高于夜晚,相较于白天,夜晚特征波段具有明显向长波移动的特征。(3)添加基于反射率构建的光谱指数及ST、SM的反演模型估测土壤碳排放速率的精度明显提升,基于一阶微分变换(1st)的支持向量机模型(SVM)模型反演矿区综合土地利用类型土壤碳排放效果最好(验证集R2=0.813、RMSE=0.116);5种不同土地利用类型土壤碳排放最佳指数组合方式存在差异,引入不同的光谱指数对土壤碳排放速率的估测精度均有不同程度的提升(验证集R2均在0.8以上),其土壤碳排放最优反演模型均可较为准确地估算红沙泉矿区不同土地利用类型土壤的碳排放速率。本研究可为荒漠化矿区土壤碳排放遥感反演提供依据,定量识别不同土地利用类型下土壤的碳源汇效应,并实现了矿区碳排放的无损探测,为我国“30·60”双碳目标提供数据支撑。 展开更多
关键词 碳排放 高光谱 不同土地利用类型 昼夜 荒漠化矿区
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