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儿童诗语言中游戏精神赏析——以《My Shadow》为例
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作者 张颖 《陕西学前师范学院学报》 2019年第8期52-55,共4页
文章介绍了史蒂文森的儿童诗集《A Child's Garden of Verses》,并以其中知名度较高的一首儿童诗《My Shadow》为例,从叙事结构和语音词汇两个角度,分析了作者充满童趣的语言中所蕴含的游戏精神,探讨了儿童诗在儿童阅读和心灵成长... 文章介绍了史蒂文森的儿童诗集《A Child's Garden of Verses》,并以其中知名度较高的一首儿童诗《My Shadow》为例,从叙事结构和语音词汇两个角度,分析了作者充满童趣的语言中所蕴含的游戏精神,探讨了儿童诗在儿童阅读和心灵成长中的价值。 展开更多
关键词 《My shadow》 史蒂文森 语言特色 游戏精神
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Color-polarization synergistic target detection method considering shadow interference
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作者 Bin Feng Jinpei Xiao +3 位作者 Junchao Zhang Lin Li Yunlong Wu Qing Ye 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第7期50-61,共12页
Aiming at the problem of shadow interference in UAV's ground reconnaissance,a color and polarization synergistic target detection method is proposed for anti-shadow interference,based on the influence of two physi... Aiming at the problem of shadow interference in UAV's ground reconnaissance,a color and polarization synergistic target detection method is proposed for anti-shadow interference,based on the influence of two physical characteristics(wavelength and polarization)under different illuminations.A valid fusion strategy is proposed via integrating two separate detection results on color and polarization images.Moreover,a local enhancement and recognition module(LER)is introduced to boost the performance.Based on our built dataset,experimental results show that our method achieves mAPof 87.76%,and12.37%higher than that of color image and 14.68%higher than that of polarization image. 展开更多
关键词 Electro-optical countermeasure Ground reconnaissance Color-polarization shadow interference Target recognition
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View of thermodynamic phase transition of the charged Gauss-Bonnet AdS black hole via the shadow
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作者 何柯腱 郭森 +1 位作者 罗智 李国平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期355-362,共8页
We examine thermodynamic phase transition(PT)of the charged Gauss-Bonnet Ad S black hole(BH)by utilizing the shadow radius.In this system,we rescale the corresponding Gauss-Bonnet coefficientαby a factor of 1/(D-4),a... We examine thermodynamic phase transition(PT)of the charged Gauss-Bonnet Ad S black hole(BH)by utilizing the shadow radius.In this system,we rescale the corresponding Gauss-Bonnet coefficientαby a factor of 1/(D-4),and ensure thatαis positive to avoid any singularity problems.The equation derived for the shadow radius indicates that it increases as the event horizon radius increases,making it an independent variable for determining BH temperature.By investigating the PT curve in relation to shadows,we can observe that the shadow radius can be used as an alternative to the event horizon radius in explaining the phenomenon of BH PT.Furthermore,the results indicate that an increase in the parameterαcorresponds to a decrease in the temperature of the BH.By utilizing the relationship between the temperature and the shadow radius,it is possible to obtain the thermal profile of the Gauss-Bonnet AdS BH.It is evident that there is an N-type variation in temperature for pressures P<P_(c).Additionally,as the parameterαincreases,the region covered by shadow expands while the temperature decreases.The utilization of BH shadows as a probe holds immense significance in gaining a deeper understanding of BH thermodynamic behavior. 展开更多
关键词 Gauss-Bonnet AdS black hole thermodynamic shadow
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An Interactive Collaborative Creation System for Shadow Puppets Based on Smooth Generative Adversarial Networks
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作者 Cheng Yang Miaojia Lou +1 位作者 Xiaoyu Chen Zixuan Ren 《Computers, Materials & Continua》 SCIE EI 2024年第6期4107-4126,共20页
Chinese shadow puppetry has been recognized as a world intangible cultural heritage.However,it faces substantial challenges in its preservation and advancement due to the intricate and labor-intensive nature of crafti... Chinese shadow puppetry has been recognized as a world intangible cultural heritage.However,it faces substantial challenges in its preservation and advancement due to the intricate and labor-intensive nature of crafting shadow puppets.To ensure the inheritance and development of this cultural heritage,it is imperative to enable traditional art to flourish in the digital era.This paper presents an Interactive Collaborative Creation System for shadow puppets,designed to facilitate the creation of high-quality shadow puppet images with greater ease.The system comprises four key functions:Image contour extraction,intelligent reference recommendation,generation network,and color adjustment,all aimed at assisting users in various aspects of the creative process,including drawing,inspiration,and content generation.Additionally,we propose an enhanced algorithm called Smooth Generative Adversarial Networks(SmoothGAN),which exhibits more stable gradient training and a greater capacity for generating high-resolution shadow puppet images.Furthermore,we have built a new dataset comprising high-quality shadow puppet images to train the shadow puppet generation model.Both qualitative and quantitative experimental results demonstrate that SmoothGAN significantly improves the quality of image generation,while our system efficiently assists users in creating high-quality shadow puppet images,with a SUS scale score of 84.4.This study provides a valuable theoretical and practical reference for the digital creation of shadow puppet art. 展开更多
关键词 shadow puppets deep learning image generation co-create
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Energy efficiency aware dynamic rate and power adaptation in carrier sensing based WLANs under Rayleigh fading and shadowing
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作者 Md.Forkan Uddin 《Digital Communications and Networks》 SCIE CSCD 2024年第4期918-933,共16页
We consider the problem of energy efficiency aware dynamic adaptation of data transmission rate and transmission power of the users in carrier sensing based Wireless Local Area Networks(WLANs)in the presence of path l... We consider the problem of energy efficiency aware dynamic adaptation of data transmission rate and transmission power of the users in carrier sensing based Wireless Local Area Networks(WLANs)in the presence of path loss,Rayleigh fading and log-normal shadowing.For a data packet transmission,we formulate an optimization problem,solve the problem,and propose a rate and transmission power adaptation scheme with a restriction methodology of data packet transmission for achieving the optimal energy efficiency.In the restriction methodology of data packet transmission,a user does not transmit a data packet if the instantaneous channel gain of the user is lower than a threshold.To evaluate the performance of the proposed scheme,we develop analytical models for computing the throughput and energy efficiency of WLANs under the proposed scheme considering a saturation traffic condition.We then validate the analytical models via simulation.We find that the proposed scheme provides better throughput and energy efficiency with acceptable throughput fairness if the restriction methodology of data packet transmission is included.By means of the analytical models and simulations,we demonstrate that the proposed scheme provides significantly higher throughput,energy efficiency and fairness index than a traditional non-adaptive scheme and an existing most relevant adaptive scheme.Throughput and energy efficiency gains obtained by the proposed scheme with respect to the existing adapting scheme are about 75%and 103%,respectively,for a fairness index of 0.8.We also study the effect of various system parameters on throughput and energy efficiency and provide various engineering insights. 展开更多
关键词 Carrier sense multiple access Energy efficiency Fading and shadowing Rate and power adaptation THROUGHPUT Wireless local area networks
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Dragons Leap with Each Passing Year, Intangible Heritage Grows Fragrant Beijing Shadow Puppetry Outreach Activities
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作者 Xin Wen 《China & The World Cultural Exchange》 2024年第3期22-23,共2页
Since ancient times,the Chinese New Year has been the most important festival for the Chinese nation,and"celebrating the Chinese New Year in museums"has gradually become a new trend in recent years.To enrich... Since ancient times,the Chinese New Year has been the most important festival for the Chinese nation,and"celebrating the Chinese New Year in museums"has gradually become a new trend in recent years.To enrich the cultural offerings during the holiday period and let the general audience experience the strong festive atmosphere in museums,on February 22 and 23,2024,on the eve of the Lantern Festival,the China Arts and Crafts Museum(China Intangible Cultural Heritage Museum)successfully held the"Encounter with Intangible Heritage""Capital Colors Shadow Play:Bejing Shadow Puppetry Outreach Activities." 展开更多
关键词 shadow offering reach
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Langzhong Shadow Play
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《China Today》 2024年第3期79-79,共1页
LANGZHONG shadow play has been popular in 36 counties and cities in the vicinity of Langzhong in southwest China’s Sichuan Province,and is one of three major styles of Sichuan shadow play.Around 350 years ago,a puppe... LANGZHONG shadow play has been popular in 36 counties and cities in the vicinity of Langzhong in southwest China’s Sichuan Province,and is one of three major styles of Sichuan shadow play.Around 350 years ago,a puppeteer named Wang Yuansheng created the Langzhong shadow play by combining the unique characteristics of different styles of shadow play with north Sichuan’s folk customs.In 2008,the art of Sichuan shadow play which Langzhong shadow play is affiliated to was listed as a national intangible culture heritage item. 展开更多
关键词 shadow LISTED shadow
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An Overview of the Achievements of Modern Research on the Flying Shadow Pavilion Pictorial
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作者 CHEN Honghui 《Cultural and Religious Studies》 2024年第2期118-122,共5页
The current academic research on the Dian Shi Zhai Pictorial founded in 1884 has been perfected,but there is very little research on the Flying Shadow Pavilion Pictorial,which can be said to be derived from Dian Shi Z... The current academic research on the Dian Shi Zhai Pictorial founded in 1884 has been perfected,but there is very little research on the Flying Shadow Pavilion Pictorial,which can be said to be derived from Dian Shi Zhai Pictorial terms of both content and form,and which was founded by the Haiist painter Wu Youru in 1890 in order to reward the increasing number of admirers,but it is still in the initial stage.Flying Shadow Pavilion Pictorial consisted of four parts:pictures of ladies in Shanghai costumes,news about current affairs,pictures of animals,and compilations of women,each of which was accompanied by the then popular notebooks,which were popular at the time among the then readers because of the matching of pictures with text and the mixing of narratives and discussions.This paper takes Flying Shadow Pavilion Pictorial as the main object,summarizes the existing literature about Flying Shadow Pavilion Pictorial,points out the deficiencies of the current research on this basis,and points out the development trend of Flying Shadow Pavilion Pictorial in the future research. 展开更多
关键词 Flying shadow Pavilion Pictorial Dian Shi Zhai Pictorial Late Qing Dynasty’s pictorial
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A Tale of Light and Shadow Chinese shadow puppetry seeks to explore new avenues
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作者 GE LIJUN 《ChinAfrica》 2024年第5期52-53,共2页
Accompanied by music,a turtle and a crane fight in a humorous story created by the simple interplay of light and curtain.This Chinese shadow puppetry performance makes the audience laugh.Backstage,Lu Baogang,a nationa... Accompanied by music,a turtle and a crane fight in a humorous story created by the simple interplay of light and curtain.This Chinese shadow puppetry performance makes the audience laugh.Backstage,Lu Baogang,a national-level inheritor of Beijing shadow puppetry art,and the other performers of the shadow puppetry troupe manipulate the silhouettes with great skill. 展开更多
关键词 shadow shadow PET
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Nanyang Shadow Puppetry-Inheritance and Challenges
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作者 代佳琪 陈圆圆(指导) 《疯狂英语(初中天地)》 2024年第11期68-69,共2页
Nanyang shadow puppetry has a long history.It originated in the Han Dynasty and grew from folk rap art,combining various art forms like painting,sculpture(雕塑),and opera.In the past,rural cultural life in Nanyang was... Nanyang shadow puppetry has a long history.It originated in the Han Dynasty and grew from folk rap art,combining various art forms like painting,sculpture(雕塑),and opera.In the past,rural cultural life in Nanyang was rare;shadow puppetry was a key form of entertainment(娱乐).During festivals,temple fairs,or slack farming seasons,troupes would visit villages to give wonderful shows. 展开更多
关键词 originated shadow shadow
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Pavement Cracks Coupled With Shadows:A New Shadow-Crack Dataset and A Shadow-Removal-Oriented Crack Detection Approach 被引量:2
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作者 Lili Fan Shen Li +3 位作者 Ying Li Bai Li Dongpu Cao Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第7期1593-1607,共15页
Automatic pavement crack detection is a critical task for maintaining the pavement stability and driving safety.The task is challenging because the shadows on the pavement may have similar intensity with the crack,whi... Automatic pavement crack detection is a critical task for maintaining the pavement stability and driving safety.The task is challenging because the shadows on the pavement may have similar intensity with the crack,which interfere with the crack detection performance.Till to the present,there still lacks efficient algorithm models and training datasets to deal with the interference brought by the shadows.To fill in the gap,we made several contributions as follows.First,we proposed a new pavement shadow and crack dataset,which contains a variety of shadow and pavement pixel size combinations.It also covers all common cracks(linear cracks and network cracks),placing higher demands on crack detection methods.Second,we designed a two-step shadow-removal-oriented crack detection approach:SROCD,which improves the performance of the algorithm by first removing the shadow and then detecting it.In addition to shadows,the method can cope with other noise disturbances.Third,we explored the mechanism of how shadows affect crack detection.Based on this mechanism,we propose a data augmentation method based on the difference in brightness values,which can adapt to brightness changes caused by seasonal and weather changes.Finally,we introduced a residual feature augmentation algorithm to detect small cracks that can predict sudden disasters,and the algorithm improves the performance of the model overall.We compare our method with the state-of-the-art methods on existing pavement crack datasets and the shadow-crack dataset,and the experimental results demonstrate the superiority of our method. 展开更多
关键词 Automatic pavement crack detection data augmentation compensation deep learning residual feature augmentation shadow removal shadow-crack dataset
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Numerical study of hydraulic fracturing in the sectorial well-factory considering well interference and stress shadowing 被引量:1
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作者 Yu-Hao Liu Jin-Tao Zhang +2 位作者 Jie Bai Feng-Shou Zhang Ji-Zhou Tang 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3567-3581,共15页
In the Changqing Oilfield in northwest China, when traditional petroleum exploitation encounters forestry reserves or water source protection areas, sectorial well-factory design is proposed. The most distinct feature... In the Changqing Oilfield in northwest China, when traditional petroleum exploitation encounters forestry reserves or water source protection areas, sectorial well-factory design is proposed. The most distinct feature of a sectorial well-factory is the deviation of the well from the minimum horizontal principal stress, resulting in hydraulic fracture deflection after the initiation, along with possible well interference (i.e., fracture hit) and fracture coalescence in the oblique wells. Four indexes describing well deflection are then proposed according to fracture morphology. Several fracturing designs, including stage arrangement, fracturing sequences, and fracturing techniques are applied to study the feasibility of the sectorial well-factory design. The results show that the “gradual” or “sparse” stage arrangement, large injection rate, and simultaneous multifracture treatment can help to optimize the fracture morphology and stimulation design. However, the subsequent stress shadowing effect usually adversely affects the fracturing of adjacent wells. With a small initial horizontal stress difference, large injection rate and staggered stage arrangement can achieve ideal stimulation performance. Our results can provide a guidance for optimizing stimulation design in unconventional well-factory while taking into account environmental protection. 展开更多
关键词 Hydraulic fracturing Sectorial well-factory Fracture deflection Well interference Stress shadowing
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Ghost-Retina Net:Fast Shadow Detection Method for Photovoltaic Panels Based on Improved Retina Net 被引量:1
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作者 Jun Wu Penghui Fan +1 位作者 Yingxin Sun Weifeng Gui 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期1305-1321,共17页
Based on the artificial intelligence algorithm of RetinaNet,we propose the Ghost-RetinaNet in this paper,a fast shadow detection method for photovoltaic panels,to solve the problems of extreme target density,large ove... Based on the artificial intelligence algorithm of RetinaNet,we propose the Ghost-RetinaNet in this paper,a fast shadow detection method for photovoltaic panels,to solve the problems of extreme target density,large overlap,high cost and poor real-time performance in photovoltaic panel shadow detection.Firstly,the Ghost CSP module based on Cross Stage Partial(CSP)is adopted in feature extraction network to improve the accuracy and detection speed.Based on extracted features,recursive feature fusion structure ismentioned to enhance the feature information of all objects.We introduce the SiLU activation function and CIoU Loss to increase the learning and generalization ability of the network and improve the positioning accuracy of the bounding box regression,respectively.Finally,in order to achieve fast detection,the Ghost strategy is chosen to lighten the size of the algorithm.The results of the experiment show that the average detection accuracy(mAP)of the algorithm can reach up to 97.17%,the model size is only 8.75 MB and the detection speed is highly up to 50.8 Frame per second(FPS),which can meet the requirements of real-time detection speed and accuracy of photovoltaic panels in the practical environment.The realization of the algorithm also provides new research methods and ideas for fault detection in the photovoltaic power generation system. 展开更多
关键词 Deep learning intensive object detection photovoltaic panel shadow Ghost module retinanet
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A GENERALIZED LIPSCHITZ SHADOWING PROPERTY FOR FLOWS
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作者 韩波 Manseob LEE 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期259-288,共30页
In this paper,we define a generalized Lipschitz shadowing property for flows and prove that a flowΦgenerated by a C1vector field X on a closed Riemannian manifold M has this generalized Lipschitz shadowing property i... In this paper,we define a generalized Lipschitz shadowing property for flows and prove that a flowΦgenerated by a C1vector field X on a closed Riemannian manifold M has this generalized Lipschitz shadowing property if and only if it is structurally stable. 展开更多
关键词 FLOW Perron property HYPERBOLICITY generalized Lipschitz shadowing property structural stability
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Shadow thermodynamics of AdS black hole with the nonlinear electrodynamics term
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作者 郑何斌 牟平辉 +1 位作者 陈芸仙 李国平 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第8期201-208,共8页
We creatively employ the shadow radius to study the thermodynamics of a charged Ad S black hole with a nonlinear electrodynamics(NLED)term.First,the connection between the shadow radius and event horizon is constructe... We creatively employ the shadow radius to study the thermodynamics of a charged Ad S black hole with a nonlinear electrodynamics(NLED)term.First,the connection between the shadow radius and event horizon is constructed with the aid of the geodesic analysis.It turns out that the black hole shadow radius shows a positive correlation as a function of the event horizon radius.Then in the shadow context,we find that the black hole temperature and heat capacity can be presented by the shadow radius.Further analysis shows that the shadow radius can work similarly to the event horizon in revealing black hole phase transition process.In this sense,we construct the thermal profile of the charged Ad S black hole with inclusion of the NLED effect.In the P<Pc case,it is found that the N-type trend of the temperature given by the shadow radius is always consistent with that obtained by using the event horizon.Thus,we can conclude for the charged Ad S black hole that the phase transition process can be intuitively presented as the thermal profile in the shadow context.Finally,the effects of NLED are carefully analyzed. 展开更多
关键词 AdS black hole the nonlinear electrodynamics shadow thermodynamics
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Improved Multileader Optimization with Shadow Encryption for Medical Images in IoT Environment
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作者 Mesfer Al Duhayyim Mohammed Maray +5 位作者 Ayman Qahmash Fatma S.Alrayes Nuha Alshuqayran Jaber S.Alzahrani Mohammed Alghamdi Abdullah Mohamed 《Computers, Materials & Continua》 SCIE EI 2023年第2期3133-3149,共17页
Nowadays,security plays an important role in Internet of Things(IoT)environment especially in medical services’domains like disease prediction and medical data storage.In healthcare sector,huge volumes of data are ge... Nowadays,security plays an important role in Internet of Things(IoT)environment especially in medical services’domains like disease prediction and medical data storage.In healthcare sector,huge volumes of data are generated on a daily basis,owing to the involvement of advanced health care devices.In general terms,health care images are highly sensitive to alterations due to which any modifications in its content can result in faulty diagnosis.At the same time,it is also significant to maintain the delicate contents of health care images during reconstruction stage.Therefore,an encryption system is required in order to raise the privacy and security of healthcare data by not leaking any sensitive data.The current study introduces Improved Multileader Optimization with Shadow Image Encryption for Medical Image Security(IMLOSIE-MIS)technique for IoT environment.The aim of the proposed IMLOSIE-MIS model is to accomplish security by generating shadows and encrypting them effectively.To do so,the presented IMLOSIE-MIS model initially generates a set of shadows for every input medical image.Besides,shadow image encryption process takes place with the help of Multileader Optimization(MLO)withHomomorphic Encryption(IMLO-HE)technique,where the optimal keys are generated with the help of MLO algorithm.On the receiver side,decryption process is initially carried out and shadow image reconstruction process is conducted.The experimentation analysis was carried out on medical images and the results inferred that the proposed IMLOSIE-MIS model is an excellent performer compared to other models.The comparison study outcomes demonstrate that IMLOSIE-MIS model is robust and offers high security in IoT-enabled healthcare environment. 展开更多
关键词 Medical image security image encryption shadow images homomorphic encryption optimal key generation
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Influence of Wind Turbine Structural Parameters on Wind Shear and Tower Shadow Effect
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作者 Yajing Zhang Chaoyang Song Zhiguo Li 《Energy Engineering》 EI 2023年第2期501-510,共10页
To overcome the problems of natural decreases in power quality,and to eliminate wind speed fluctuation due to wind shear and tower shadow effect arising from wind turbine structural parameters,an improved prediction m... To overcome the problems of natural decreases in power quality,and to eliminate wind speed fluctuation due to wind shear and tower shadow effect arising from wind turbine structural parameters,an improved prediction model accounting for the dual effect of wind shear and tower shadow is,in this paper,built.Compared to the conventional prediction model,the proposed model contains a new constraint condition,which makes the disturbance term caused by the tower shadow effect always negative so that the prediction result is closer to the actual situation.Furthermore,wind turbine structural parameters such as hub height,rotor diameter,the diameter of the tower top,and rotor overhang on wind shear and tower shadow effect are also explored in detail.The results show that the wind shear effect became weaker with the increase in hub height.The hub height is independent of the tower shadow effect.The rotor diameter is positively correlated with the wind shear and tower shadow effect.The tower shadow effect is positively correlated with the diameter of the tower top and negatively correlated with the rotor overhang. 展开更多
关键词 Wind turbine wind shear tower shadow effect dual effect structural parameters
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基于ARShadowGAN的增强现实场景中物体阴影生成算法——以苏州博物馆藏品为例
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作者 周亚峰 金益 +2 位作者 祁昌丰 李铃祥 章语轩 《无线互联科技》 2023年第23期118-120,124,共4页
在增强现实应用中,虚拟物体的阴影对真实性起着重要作用,但通常难以获得逼真的虚拟阴影。文章实验了一种基于生成对抗网络的用于增强现实场景中物体阴影生成的算法,并以苏州博物馆的珍贵藏品为例进行了详细研究。ARShadowGAN算法采用生... 在增强现实应用中,虚拟物体的阴影对真实性起着重要作用,但通常难以获得逼真的虚拟阴影。文章实验了一种基于生成对抗网络的用于增强现实场景中物体阴影生成的算法,并以苏州博物馆的珍贵藏品为例进行了详细研究。ARShadowGAN算法采用生成对抗网络的方法,通过深度学习生成合理的虚拟物体阴影,以更好地融合虚拟物体与真实场景。文章以苏州博物馆的藏品为案例展开研究,证明该算法的有效性和适用性。实验结果表明:ARShadowGAN能在增强现实场景中生成逼真的物体阴影,使虚拟物体与真实世界无缝融合。 展开更多
关键词 虚拟阴影生成 增强现实 生成对抗网络
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ShadowDB:基于SQL引擎的全链路压力测试分流系统
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作者 姜俊 李文慧 +2 位作者 张亮 王善民 李瑞远 《计算机工程与科学》 CSCD 北大核心 2023年第12期2165-2174,共10页
全链路压力测试作为一种新兴的软件测试技术,直接在生产系统中做压力测试,旨在准确评估线上环境的性能。基于影子库的数据分流技术能够保证全链路压力测试过程中生产数据不受测试污染。基于SQL引擎技术设计并实现了一套完整的针对全链... 全链路压力测试作为一种新兴的软件测试技术,直接在生产系统中做压力测试,旨在准确评估线上环境的性能。基于影子库的数据分流技术能够保证全链路压力测试过程中生产数据不受测试污染。基于SQL引擎技术设计并实现了一套完整的针对全链路压力测试的开源数据分流系统ShadowDB,其基本思想是通过SQL解析、SQL路由对用户请求正确分流。ShadowDB目前支持6种关系型数据库系统中所有SQL语句的数据分流;提出了2种数据分流算法:基于列的影子算法和基于Hint的影子算法;实现了所有JDBC的接口,允许线上应用程序无需修改代码即可使用ShadowDB;ShadowDB嵌入应用程序中,无需网络转发请求,对请求效率影响很小,保证了全链路压力测试结果的可靠性。使用2个通用的性能测试工具进行了大量的实验,结果表明ShadowDB的性能远远高于对比方案的。 展开更多
关键词 全链路压力测试 SQL引擎 数据分流 影子库
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许氏平鲉幼鱼对人工鱼礁模型不同阴影情况的行为响应 被引量:1
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作者 唐衍力 林嘉政 +2 位作者 王欣 于浩林 王欣欣 《中国海洋大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期26-34,共9页
阴影效应是影响人工鱼礁诱集效果的主要因素之一,为研究许氏平鲉(Sebastes schlegelii)对人工鱼礁不同阴影情况的行为响应,采用室内模拟实验方法,在实验水槽顶部固定光源,共设计3组实验:A组实验探究不同阴影面积的鱼礁模型对实验鱼的诱... 阴影效应是影响人工鱼礁诱集效果的主要因素之一,为研究许氏平鲉(Sebastes schlegelii)对人工鱼礁不同阴影情况的行为响应,采用室内模拟实验方法,在实验水槽顶部固定光源,共设计3组实验:A组实验探究不同阴影面积的鱼礁模型对实验鱼的诱集效果;B组实验探究不放置鱼礁模型、悬挂不同开孔率顶板对实验鱼的诱集效果;C组实验探究阴影面积相同但开孔数量不同的鱼礁模型对实验鱼的诱集效果;对照组实验水槽中不放置鱼礁模型、不悬挂顶板。观察并记录许氏平鲉幼鱼(体长(5.06±0.09)cm,体质量(3.22±0.16)g)在水槽中的行为与分布特征。研究表明:3个实验组中许氏平鲉在鱼礁放置区域的出现率均显著高于对照组和其他区域;A组实验中,许氏平鲉在鱼礁放置区的平均出现率随着鱼礁阴影面积的增大而上升;B组实验中,许氏平鲉在顶板放置区的平均出现率显著高于对照组,但不同水平组之间差异不显著;C组实验中,开孔数为1时许氏平鲉在鱼礁放置区的平均出现率与开孔数为9时相近且高于开孔数为4和6时。研究结果表明,阴影面积越大的人工鱼礁对许氏平鲉的诱集效果越好,阴影面积相同时开孔数较多的人工鱼礁能够在提供良好庇护所的同时保证诱集效果。 展开更多
关键词 人工鱼礁 许氏平鲉 阴影效应 行为响应 诱集
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