Numerical study of hydraulic fracturing in the sectorial well-factory considering well interference and stress shadowing

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.

A GENERALIZED LIPSCHITZ SHADOWING PROPERTY FOR FLOWS

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.

View of thermodynamic phase transition of the charged Gauss-Bonnet AdS black hole via the shadow

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.

An Interactive Collaborative Creation System for Shadow Puppets Based on Smooth Generative Adversarial Networks

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.

Color-polarization synergistic target detection method considering shadow interference

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.

Langzhong Shadow Play

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.

Dragons Leap with Each Passing Year, Intangible Heritage Grows Fragrant Beijing Shadow Puppetry Outreach Activities

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."

A Tale of Light and Shadow Chinese shadow puppetry seeks to explore new avenues

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.

An Overview of the Achievements of Modern Research on the Flying Shadow Pavilion Pictorial

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.

基于Shadowing模型的无线入侵主机物理定位研究

为了在室内无线局域网环境中及时准确地定位非法入侵主机物理位置,以无线信号强度衰减过程的Shadowing传播模型为基础,研究了在一定的范围内如何合理地布置探测器,如何根据接收到的入侵主机的信号强度进行物理定位的问题.提出的定位方法可以有效地对抗入侵主机随机更改信号发射功率对定位精度的影响.实际测试结果表明,该方法定位误差平均约为2.3 m,可以满足室内环境下定位非法入侵主机的需求.

圆环上的逆shadowing映射(英文)

本文证明了圆环上shadowing性质和(Tc,Th-)逆shadowing性质的等价性.

On the Relation of Shadowing and Expansivity in Nonautonomous Discrete Systems

In this paper we study shadowing property for sequences of mappings on compact metric spaces, i.e., nonautonomous discrete dynamical systems. We investi- gate the relations of various expansivity properties with shadowing and h-shadowing property.

Review of Shadow Detection and De-shadowing Methods in Remote Sensing

Shadow is one of the major problems in remotely sensed imagery which hampers the accuracy of information extraction and change detection.In these images,shadow is generally produced by different objects,namely,cloud,mountain and urban materials.The shadow correction process consists of two steps:detection and de-shadowing.This paper reviews a range of techniques for both steps,focusing on urban regions(urban shadows),mountainous areas(topographic shadow),cloud shadows and composite shadows.Several issues including the problems and the advantages of those algorithms are discussed.In recent years,thresholding and recovery techniques have become important for shadow detection and de-shadowing,respectively.Research on shadow correction is still an important topic,particularly for urban regions(in high spatial resolution data) and mountainous forest(in high and medium spatial resolution data).Moreover,new algorithms are needed for shadow correction,especially given the advent of new satellite images.

SHADOWING,EXPANSIVENESS AND SPECIFICATION FOR C^1-CONSERVATIVE SYSTEMS

We prove that a Cl-generic volume-preserving dynamical system （diffeomor- phism or flow） has the shadowing property or is expansive or has the weak specification property if and only if it is Anosov. Finally, as in [10, 27], we prove that the Cl-robustness, within the volume-preserving context, of the expansiveness property and the weak specifica- tion property, imply that the dynamical system （diffeomorphism or flow） is Anosov.

Inhomogeneous Shadowing Effect in High-Energy p-A Drell-Yan Process:

Having studied the initial state energy loss versus nuclear shadowing for the Drell-Yan dimuon pairproduction in the color string model,the inhomogeneous shadowing effect is considered in this paper.We find thatthe inhomogeneous shadowing effect does amend the rate of energy loss per unit path length,-dE/dz.Finally,thetheoretical results for the Drell-Yan differential cross-section ratios are compared with the E772 and E866 data.It isfound that the theoretical results are in good agreement with the experimental data.

Inverse Shadowing and Weak Inverse Shadowing Property

In this paper we show that an -stable diffeomorphism has the weak inverse shadowing property with respect to classes of continuous method and and some of the -stable diffeomorphisms have weak inverse shadowing property with respect to classes . In addition we study relation between minimality and weak inverse shadowing property with respect to class and relation between expansivity and inverse shadowing property with respect to class .

Precise Asymptotic Distribution of the Number of Isolated Nodes in Wireless Networks with Lognormal Shadowing

In this paper, we study the connectivity of multihop wireless networks under the log-normal shadowing model by investigating the precise distribution of the number of isolated nodes. Under such a realistic shadowing model, all previous known works on the distribution of the number of isolated nodes were obtained only based on simulation studies or by ignoring the important boundary effect to avoid the challenging technical analysis, and thus cannot be applied to any practical wireless networks. It is extremely challenging to take the complicated boundary effect into consideration under such a realistic model because the transmission area of each node is an irregular region other than a circular area. Assume that the wireless nodes are represented by a Poisson point process with densitynover a unit-area disk, and that the transmission power is properly chosen so that the expected node degree of the network equals lnn + ξ (n), where ξ (n) approaches to a constant ξ as n →?∞. Under such a shadowing model with the boundary effect taken into consideration, we proved that the total number of isolated nodes is asymptotically Poisson with mean e$ {-ξ}. The Brun’s sieve is utilized to derive the precise asymptotic distribution. Our results can be used as design guidelines for any practical multihop wireless network where both the shadowing and boundary effects must be taken into consideration.

关于“shadowing exercise”方法在日语语法教学中的延伸应用研究

在教学过程中发现,很多学生无法摆脱母语迁移的负面影响。学习语法时,习惯将语法的语义高度概括并用汉语记忆,将例句的译文优先记忆,以辅助回忆日语原句。这导致很多学生的学习滞步不前。本文借鉴＂shadowing exercise＂方法,将其应用延伸至日语语法教学中,以期帮助学生摆脱母语迁移的负面影响。

Pavement Cracks Coupled With Shadows:A New Shadow-Crack Dataset and A Shadow-Removal-Oriented Crack Detection Approach

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.

Ghost-Retina Net:Fast Shadow Detection Method for Photovoltaic Panels Based on Improved Retina Net

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.