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In this study, we investigate the deflection angle of a torus-like regular charged black hole in the limit approximation of a weak field to check the effects of non-magnetic plasma and non-plasma medium. Using spacetime optical geometry, we first compute the Gaussian optical curvature. We study the light deflection angle from a charged torus-like black hole using the Gibbons and Werner approach. By taking into account the well-known Keeton–Petters approach, we validate our results. Moreover, we examine the shadow of a charged torus-like black hole by using the ray-tracing algorithm under the influence of pressureless and non-magnetized plasma and study the graphical effects of cosmological constant and charge for both anti-de Sitter and de Sitter cases on the shadow of a black hole. [ABSTRACT FROM AUTHOR]

ABSTRACT Shadow is a lightweight AND‐RX block cipher adapted for resource‐constrained devices. In this paper, software and hardware optimizations are proposed respectively for Shadow to enhance its implementation performance. For software optimization, this paper first proposes a data pre‐processing scheme based on the structural characteristics of the round function. It further improves the optimization effect of the barrel shifter instruction while simplifying the implementation process of the round function. Note that the optimization strategy is also applicable to other AND‐RX ciphers. Secondly, this paper proposes a new NX operation implementation scheme that can effectively reduce its instruction cycles. In round‐based architecture, experimental results show that our scheme effectively reduces code size by 24.7%, Flash consumption by 12.6%, and total instruction cycles by 25.1%. Meanwhile, in the fully unrolled architecture, our scheme reduces code size by 30.8%, Flash consumption by 29.8%, and total instruction cycles by 28.1%. For hardware optimization, this paper proposes a low‐resource implementation scheme by constructing a generic formula for NX operation. In ASIC implementation, our scheme reduces hardware resources by 72.3%. In FPGA implementation, the number of LUTs and Slices is reduced by 30% and 28.6%, respectively. Overall, the proposed optimization scheme for Shadow has better performance in hardware and software implementation. [ABSTRACT FROM AUTHOR]

Objectives This study aimed to fill in a gap in the research base on the applicability of psychotherapeutic approaches to coaching psychology. Thus, it explored the transference of knowledge, skills and expertise from Jungian psychology into coaching psychology. Methods The qualitative study investigated the perceptions and experiences of professional coaches and coaching psychologists with a Jungian approach to coaching, particularly with an intervention called the Jungian coaching method. This was done through semi-structured interviews with 6 professional coaches, from 4 different countries. Interpretative phenomenological analysis was used to analyse the collected data. Results Three main themes were identified: a unique coaching frame; a Jungian coaching method and its tools support the coach; and a Jungian coaching method and its tools empower the client and enable deeper exploration. Discussion Novel concept of coaching container is proposed, with the unconscious as an important element. The unique Jungian conceptualisation of the unconscious could be further investigated for its potential contributions to coaching psychology as a resource during the coaching process. Conclusion The findings suggest that a Jungian approach to coaching might be a feasible application of psychotherapy knowledge into coaching psychology, which enriches the coaching experience of both the coach and the coachee. [ABSTRACT FROM AUTHOR]

High-resolution digital elevation models (DEMs) of the lunar surface are crucial for lunar exploration missions and scientific research. The emergence of advanced technologies, such as Shape-from-Shading (SfS), has enabled the generation of pixel-wise high-resolution DEMs from monocular images of the lunar surface. However, SfS encounters significant challenges in locations with limited illumination, such as the lunar south pole, where the surface is largely covered by shadows. Therefore, this paper presents a novel shadow-constrained SfS approach for pixel-wise 3D surface reconstruction at the lunar south pole. The proposed approach uses multiple high-resolution images captured under different illumination conditions and an existing low-resolution DEM as the inputs and generates a high-resolution DEM with the same resolution as that of the input image through hierarchical SfS processing incorporating shadow constraints. Experiments were conducted using actual images collected by the Lunar Reconnaissance Orbiter (LRO) Narrow Angle Camera (NAC) at the lunar south pole. Comparisons with respect to photogrammetric DEMs generated from stereo NAC images show that the DEMs generated using the proposed approach exhibit the smallest root mean square error (RMSE). Moreover, shaded relief images rendered from the DEMs generated using the proposed approach demonstrate the highest similarity to the actual NAC images. Detailed profile comparisons further validate the effectiveness of the shadow constraint in optimizing 3D reconstruction in regions in proximity to shadows and within shadowed regions. The proposed shadow-constrained SfS approach can be used to generate high-resolution DEMs to support future missions to explore the lunar south pole, with applications including landing site evaluation and route planning for lunar probes or astronauts.

Light availability and distribution play an important role in every ecosystem as these affect a variety of ecosystem processes and functions. To estimate light availability and distribution, light simulations can be used. Many previous models were based on highly simplified tree models and geometrical assumptions about tree form, or were sophisticated and computationally demanding models based on 3D data which had to be acquired in every season to be simulated. The aim of this study was to model the shadow cast by individual trees at high spatial and temporal resolution without the need for repeated data collection during multiple seasons. For our approach, we captured trees under leaf-off conditions using terrestrial laser scanning and simulated leaf-on conditions for individual trees over the remainder of the year. The model was validated against light measurements ( n = 20,436 ) collected using 60 quantum sensors underneath an apple tree (Malus domestica Borkh.) on a sunny and cloudless summer day. On this day, the leaves and the shadow were simulated with a high spatial (1 cm) and temporal resolution (1 min). The simulated values were highly correlated with the measured radiation at r = 0.84 . Additionally, we simulated the radiation for a whole year for the sample apple tree (tree height: 6.6 m, crown width: 7.6 m) with a resolution of 10 cm and a temporal resolution of 10 min. Below the tree, an area of 49.55 m² is exposed to a radiation reduction of at least 10%, 17.74 m² to at least 20% and only 0.12 m² to at least 30%. The model could be further improved by incorporating branch growth, curved leaf surfaces, and gravity to take the weight of the foliage into account. The presented approach offers a high potential for modelling the light availability in the surroundings of trees with an unprecedented spatial and temporal resolution. [ABSTRACT FROM AUTHOR]

Shadows, as all other objects that surround us, are incorporated into the body and extend the body mediating perceptual information. The current study investigates the hypothesis according to which the perception of object shadows would predict the perception of body shadows. 38 participants (19 males and 19 females) aged 23 years on average were immersed into a virtual reality environment and instructed to perceive and indicate the coincidence or non coincidence between the movement of a ball shadow with regard to ball movement on the one hand, and between their body shadow and their body position in space on the other. Their brain activity was recording via a 32-channel EEG system, in which beta (13.5-30 Hz) oscillations were analyzed. A series of Multiple Regression Analysis (MRA) revealed that the beta dynamic oscillations patterns of the bilateral occipito-parieto-frontal pathway associated with the perception of ball shadow appeared to be a significant predictor of the increase in beta oscillations across frontal areas related to the body shadow perception and the decrease in beta oscillations across frontal areas connected to the decision making of the body shadow. Taken together, the findings suggest that inferential thinking ability relative to body shadow would be reliably predicted from object shadows and that the bilateral beta oscillatory modulations would be indicative of the formation of predictive neural frontal assemblies, which encode and infer body shadow neural representation, that is, a substitution of the physical body. [ABSTRACT FROM AUTHOR]

Purpose: To develop a tissue field‐filtering algorithm, called maximum spherical mean value (mSMV), for reducing shadow artifacts in QSM of the brain without requiring brain‐tissue erosion. Theory and Methods: Residual background field is a major source of shadow artifacts in QSM. The mSMV algorithm filters large field‐magnitude values near the border, where the maximum value of the harmonic background field is located. The effectiveness of mSMV for artifact removal was evaluated by comparing existing QSM algorithms in numerical brain simulation as well as using in vivo human data acquired from 11 healthy volunteers and 93 patients. Results: Numerical simulation showed that mSMV reduces shadow artifacts and improves QSM accuracy. Better shadow reduction, as demonstrated by lower QSM variation in the gray matter and higher QSM image quality score, was also observed in healthy subjects and in patients with hemorrhages, stroke, and multiple sclerosis. Conclusion: The mSMV algorithm allows QSM maps that are substantially equivalent to those obtained using SMV‐filtered dipole inversion without eroding the volume of interest. [ABSTRACT FROM AUTHOR]

Recent observations of black hole shadows have revolutionized our ability to probe gravity in extreme environments. This manuscript presents a novel analytic method to calculate, in leading-order terms, the key parameters of photon sphere and shadow radius. This method offers advantages for complex metrics where traditional approaches are cumbersome. We further explore the impact of black hole mass on the photon sphere radius, providing insights into black hole interactions with their surroundings. Our findings contribute significantly to black hole physics and gravity under extreme conditions. By leveraging future advancements in observations, such as the next-generation Event Horizon Telescope (ngEHT), this work paves the way for even more precise tests of gravity near black holes.

Extracting building heights from single-view remote sensing images greatly enhances the application of remote sensing data. While methods for extracting building height from single-view shadow images have been widely studied, it remains a challenging task. The main reasons are as follows: 1) the traditional method for extracting shadow information exhibits low accuracy; and 2) the use of only shadow information to extract building height results in limited application scenarios. To solve the above problems, this article introduces building side and shadow information to complement each other, and proposes a building height extraction method from high-resolution single-view remote sensing images using shadow and side information. First, we propose the RMU-Net method, which utilizes multiscale features for the extraction of shadow and side information. This method aims to address issues related to pixel detail loss and imprecise edge segmentation, which result from significant scale differences within segmentation targets. Additionally, we employ the area threshold method to optimize the segmentation results, specifically to tackle small stray patches and holes, enhancing the overall integrity and accuracy of shadow and side information extraction. Second, we propose a method for building height extraction that integrates shadow and side information based on an enhanced proportional coefficient model. The accuracy of measuring building side and shadow lengths is improved by incorporating the fishing net method, informed by our analysis of the geometric relationships among buildings. Finally, we establish a dataset containing building shadow and side information from remote sensing images, and select multiple areas for experimental analysis. The results demonstrate a shadow extraction accuracy of 91.03% and a side extraction accuracy of 90.29%. Additionally, the average absolute error (MAE) for building height extraction is 1.22, while the average root mean square error is 1.21. Furthermore, the proposed method's validity and scalability are affirmed through experimental analyses of applicability and anti-interference performance in extensive areas.

Accurate estimation of fractional vegetation coverage (FVC) is essential for assessing the ecological environment and acquiring ecological information. However, under natural lighting conditions, shadows in vegetation scenes can easily lead to confusion between shadowed vegetation and shadowed soil, leading to misclassification and omission errors. This issue limits the precision of both vegetation extraction and FVC estimation. To address this challenge, this study introduces a novel deep learning model, the Mixture of Modality Transformer (MoMFormer), which is specifically designed to mitigate shadow interference in vegetation extraction. Our model uses the Swin-transformer V2 as a feature extractor, effectively capturing vegetation features from a dual-modality (regular-exposure RGB and high dynamic range HDR) dataset. A dynamic aggregation module (DAM) is integrated to adaptively blend the most relevant vegetation features. We selected several state-of-the-art (SOTA) methods and conducted extensive experiments using a self-annotated dataset featuring diverse vegetation–soil scenes and compare our model with several state-of-the-art methods. The results demonstrate that MoMFormer achieves an accuracy of 89.43 % on the HDR-RGB dual-modality dataset, with an FVC accuracy of 87.57 %, outperforming other algorithms and demonstrating high vegetation extraction accuracy and adaptability under natural lighting conditions. This research offers new insights into accurate vegetation information extraction in naturally lit environments with shadows, providing robust technical support for high-precision validation of vegetation coverage products and algorithms based on multimodal data. The code and datasets used in this study are publicly available at https://github.com/hhhxiaohe/MoMFormer.

We study null and timelike constant radii geodesics in the environment of an over-spinning putative Kerr-type naked singularity. We are particularly interested in two topics: first, the differences of the shadows of the naked rotating singularity and the Kerr black hole; and second, the spinning down effect of the particles falling from the accretion disk. Around the naked singularity, the non-equatorial prograde orbits in the Kerr black hole remain intact up to a critical rotation parameter ( α = 6 3 − 9 ) and cease to exist above this value (Charbulák and Stuchlík 2018 Eur. Phys. J. C 78 879). This has an important consequence in the shadow of the naked singularity if the shadow is registered by an observer on the polar plane or close to it as the shadow cannot be distinguished from that of a Kerr black hole viewed from the same angle considering only the light emanating from the unstable photon orbits. We show that the timelike retrograde orbits in the equatorial plane immediately (after about an 8% increase in mass for the case of initial α = 1.5) reduce the spin parameter of the naked singularity from larger values to α = 1 at which an event horizon appears. This happens because the retrograde orbits have a larger capture cross-section than the prograde ones. So if a naked singularity happens to have an accretion disk, it will not remain naked for long, an event horizon forms. [ABSTRACT FROM AUTHOR]

Numerical simulations of dust emission processes are essential for dust cycle modeling and dust‐atmosphere interactions. Models have coarse spatial resolutions which, without tackling sub‐grid scale heterogeneity, bias finely resolved dust emission. Soil surface wind friction velocity (us*) drives dust emission non‐linearly with increasing model resolution, due mainly to thresholds of sediment entrainment. Albedo is area‐integrated, scales linearly with resolution, is related to us* and hence represents its sub‐grid scale heterogeneity. Calibrated albedo‐based global dust emission estimates decreased by only 2 Tg y−1 (10.5%) upscaled from 0.5 to 111 km, largely independent of resolution. Without adjusting wind fields, this scaling uncertainty is within recent estimates of global dust emission model uncertainty (±14.9 Tg y−1). This intrinsic scaling capability of the albedo‐based approach offers considerable potential to reduce resolution dependency of dust cycle modeling and improve the representation of local dust emission in Earth system models and operational air quality forecasting. Plain Language Summary: Global computer models for atmospheric dust were developed to understand the global dust cycle. However, these coarse resolution global dust models cannot accurately represent small‐scale dust emission processes and partly cause different dust emission estimations between the models. Using our new approach based on satellite products, we show that global dust emission estimation is largely independent of model resolution. Key Points: Wind friction velocity calibrated to linearly upscaled albedo was largely independent of model resolution between 0.5 and 111 kmWithout modifying wind fields, global dust emissions decreased by only 10.5% (within model uncertainty) from 0.5 to 111 km model resolutionSub‐grid scale heterogeneity is necessary to accurately represent grain‐scale sediment supply and entrainment in large scale modeling [ABSTRACT FROM AUTHOR]

This study presents how five five-year-olds express different ways of experiencing the multifaceted phenomenon of shadow, when reading and listening to picturebooks about shadow in a Swedish preschool. This is studied with attention to children's perspectives on shadow as it appears in conversations about the picturebooks. The purpose of this study is to contribute knowledge about ways of experiencing shadow, foregrounded in children's conversations about picturebooks, and answers the question 'How do children experience shadow when discussing picturebooks about shadow?' The results show that, in conversations about the picturebooks, the children express that they experience shadow as visible with light and projection surface, as manageable like tangible objects, as being influenced by someone or something, and as self-acting with fictional abilities. The children often express their experiencing shadow as related to experiences of shadow from their everyday lives, and less often as something fictional and aesthetic. [ABSTRACT FROM AUTHOR]

A special class of monotone Boolean functions coming from shadow minimization theory of finite set-systems – KK-MBF functions – is considered. These functions are a descriptive model for systems of compatible groups of constraints, however, the class of all functions is unambiguously complex and it is sensible to study relatively simple subclasses of functions such as KK-MBF. Zeros of KK-MBF functions correspond to initial segments of lexicographic order on hypercube layers. This property is used to simplify the recognition. Lexicographic order applies priorities over constraints which is applicable property of practices. Query-based algorithms for KK-MBF functions are investigated in terms of their complexities. [ABSTRACT FROM AUTHOR]

In this paper, we construct the slowly rotating case of an asymptotically flat supermassive black hole embedded in dark matter using Newman–Janis procedure. Our analysis is carried with respect to the involved parameters including the halo total mass M and the galaxy's lengthscale a 0 . Concretly, we investigate the dark matter impact on the effective potential and the photon sphere. In particular, we find that the lengthscale a 0 controles such potential values. Indeed, for low a 0 values, we find that the halo total mass M decreases the potential values significantly while for high a 0 values such impact is diluted. Regarding the shadow aspects, we show that the shadow size is much smaller for high values of a 0 while the opposite effect is observed when the halo total mass M is increased. By comparing our case to the slowly rotating case, we notice that the former exhibits a shadow shifted from its center to the left side. Finally, we compute the deflection angle in the weak-limit approximation and inspect the dark matter parameters influence. By ploting such quantity, we observe that one should expect lower bending angle values for black holes in galactic nuclei. [ABSTRACT FROM AUTHOR]

Clear images are crucial for the optimal performance of various high-level vision-based tasks. However, some inevitable causes, such as bad weather and underwater conditions degrade scene visibility. The tiny particles present in the air absorb and scatter light, causing severe attenuation that results in unclear, low-brightness, and poor-contrast images. Several techniques have been introduced to restore the degradation. However, no model exists to date that can restore multiple degradations using a single model. Therefore, to improve the scene visibility, a unified model called a Multidomain Contextual Conditional Generative Adversarial Network (MCCGAN) is designed, which uses the same parameters across the domains to restore multiple degradations such as fog, haze, rain streaks, snowflakes, smoke, shadows, underwater, and muddy underwater. The proposed model has a novel addition of multiple 1 × 1 convolutional context encoding bottleneck layers between a simple lightweight eight-block encoder and decoder with skip connections which learns the context of each input domain thoroughly, thus generating better-restored images. The MCCGAN is qualitatively and quantitatively compared to various state-of-the-art image-to-image translation models and tested on a few real unseen image domains such as smog, dust, and lightning, and the obtained results successfully improved scene visibility, proving the generalizability of MCCGAN. Moreover, the MS-COCO 2017 validation dataset is used for comparing the performance of object detection, instance segmentation, and image captioning on (1) weather-degraded images, (2) restored images by MCCGAN, and (3) ground truth images, and the results demonstrated the success of our model. An ablation study is also carried out to check the significance of the discriminator, skip connections, and bottleneck layers in MCCGAN, and the analysis suggests that MCCGAN performs better by adding a discriminator, skip connections, and four bottleneck layers in the generator architecture. [ABSTRACT FROM AUTHOR]

The article centers on two novels by Italian writer Antonio Tabucchi--Requiem: A hallucination and For Isabel: A mandala. It analyzes the polysemic elements that constitute the symbolic construction of both works, supported by the main tenets of Jungian psychology and in particular the notions of coniunctio oppositorum, individuation, and journey of self-discovery. The investigation explores the relationship of Tabucchi's narrative with works by Ferdinando Pessoa and Herman Hesse. Homologies between the author's view of the self, cognition, human reality, and the formal structure of the novels are examined through the Bakhtinian notion of dialogical narrative and through his metaliterary and self-reflexive mode of writing. [ABSTRACT FROM AUTHOR]

Henry Abramovitch has written a mystery that astonishingly replicates the process of individuation in Jungian analytical treatment. Like any mystery it focuses on uncovering clues to the problem and finding a solution. This story is assisted by the guide of the analyst and the active imagination of the client in the character of Sherlock Holmes, of all people. The book brings into question the personality and role of the analyst, the meaning of the symptom, and the personality and role of the client. Like analysis, the ending is a surprise, culminating from a startling beginning plot line with spell-binding intrigue. [ABSTRACT FROM AUTHOR]

Let $\mathcal{F}$ be an intersecting family. A $(k-1)$ -set $E$ is called a unique shadow if it is contained in exactly one member of $\mathcal{F}$. Let ${\mathcal{A}}=\{A\in \binom{[n]}{k}\colon |A\cap \{1,2,3\}|\geq 2\}$. In the present paper, we show that for $n\geq 28k$ , $\mathcal{A}$ is the unique family attaining the maximum size among all intersecting families without unique shadow. Several other results of a similar flavour are established as well. [ABSTRACT FROM AUTHOR]

This article is an attempt to analyze the process of individuation of the main character. The process of individuation means to know oneself. The novel is the main source of data collection. Books, research articles are secondary sources. This research is qualitative. Research approach is inductive. Research technique is interpretive content analysis. The current study indicates that psychological strength of all human beings is intertwined with the socially undesirable contents of personality. By embracing these unwelcome parts, the search for the self is nearly completed. The search for self-identity is important and cannot be ignored. A person suffers from mental, physical and social issues due to lack of attention to the self and his lack of ability to recognize and integrate the opposites of good and bad in the form of "persona", "shadow" and the likes in him. Such a person suffers from psychological disorders. Psychoanalytic theory can be applied to study other characters of the novel. [ABSTRACT FROM AUTHOR]

Most studies on building height estimation using remote sensing imagery mainly focus on urban buildings with relatively regular shape and relatively flat terrain, and pay little attention to large buildings with complex terrain like dams. A new dam height measurement method was proposed in this paper, which used shadow measurement data and metadata from multiple image sources. The method not only considers the geometric relationship between the sun, the satellite and the dam, but also considers the influence of the satellite zenith and introduces the correction factor, which brings the higher precision. Two dams with a maximum height of more than 200 m were studied, and the dam height is estimated by considering the topography around the dam and the shape of the dam. The experimental results show that the Mean Relative Error (MRE) of the estimated dam height using our proposed method are 3.1% and 4.7% for our two study areas, while the MRE of the traditional models is more than 13%. By doing so, we are able to calculate dam height and obtain information on temporal changes in dam height during the construction process, even in situations without a Digital Surface Model (DSM). Therefore, the proposed method will be propitious to the dynamic supervision of the construction process of the dams effectively.

Shadows, as all other objects that surround us, are incorporated into the body and extend the body mediating perceptual information. The current study investigates the hypothesis according to which the perception of object shadows would predict the perception of body shadows. 38 participants (19 males and 19 females) aged 23 years on average were immersed into a virtual reality environment and instructed to perceive and indicate the coincidence or non coincidence between the movement of a ball shadow with regard to ball movement on the one hand, and between their body shadow and their body position in space on the other. Their brain activity was recording via a 32-channel EEG system, in which beta (13.5–30 Hz) oscillations were analyzed. A series of Multiple Regression Analysis (MRA) revealed that the beta dynamic oscillations patterns of the bilateral occipito-parieto-frontal pathway associated with the perception of ball shadow appeared to be a significant predictor of the increase in beta oscillations across frontal areas related to the body shadow perception and the decrease in beta oscillations across frontal areas connected to the decision making of the body shadow. Taken together, the findings suggest that inferential thinking ability relative to body shadow would be reliably predicted from object shadows and that the bilateral beta oscillatory modulations would be indicative of the formation of predictive neural frontal assemblies, which encode and infer body shadow neural representation, that is, a substitution of the physical body.

This article traces Jonathan Swift’s legacy in the work of three modern Irish poets: Jessica Traynor, Rita Ann Higgins and Derek Mahon. I use two motifs to explore this inheritance: institutions and shadows. Using the work of Genevieve Lloyd, I argue that meaningful engagement with Enlightenment’s legacy must recognise its moral ambiguity and emotional complexity through the metaphor of shadow. Institutions, whether in the case of St Patrick’s Hospital, Dublin (Ireland’s first psychiatric hospital, founded by Swift), the residential institutions of the twentieth century or the modern apparatus of Direct Provision, embody a continuing legacy of suffering, control and containment. Imagination and empathy are the difficult but necessary means through which these legacies must be acknowledged and confronted.

Abstract Lightweight block ciphers are the essential encryption algorithm for devices with limited resources. Its goal is to ensure the security of data transmission through resource-constrained devices. Impossible differential cryptanalysis is one of the most effective cryptanalysis on block ciphers, and assessing the ability of resisting this attack is a basic design criterion. Shadow is a lightweight block cipher proposed by Guo et al. (IEEE Internet Things J 8(16):13014–13023, 2021). It utilizes a combination of ARX operations and generalized Feistel structure to overcome the weakness of the traditional Feistel structure that only diffuses half in one round. In this paper, we focus on the differential property of Shadow and its security against impossible differential cryptanalysis. First, we use the SAT method to automatically search for a full-round impossible differential distinguisher of Shadow-32. Then, based on the experimental results, we prove that Shadow has a differential property with probability 1 based on the propagation of the state. Further, we can obtain an impossible differential distinguisher for an arbitrary number of rounds of Shadow. Finally, we perform a full key recovery attack on the full-round Shadow-32 and Shadow-64. Both experimentally and theoretically, our results indicate that Shadow is critically flawed, and regardless of the security strength of the internal components and the number of rounds applied, the overall cipher remains vulnerable to impossible differential cryptanalysis.

Lightweight block ciphers are the essential encryption algorithm for devices with limited resources. Its goal is to ensure the security of data transmission through resource-constrained devices. Impossible differential cryptanalysis is one of the most effective cryptanalysis on block ciphers, and assessing the ability of resisting this attack is a basic design criterion. Shadow is a lightweight block cipher proposed by Guo et al. (IEEE Internet Things J 8(16):13014–13023, 2021). It utilizes a combination of ARX operations and generalized Feistel structure to overcome the weakness of the traditional Feistel structure that only diffuses half in one round. In this paper, we focus on the differential property of Shadow and its security against impossible differential cryptanalysis. First, we use the SAT method to automatically search for a full-round impossible differential distinguisher of Shadow-32. Then, based on the experimental results, we prove that Shadow has a differential property with probability 1 based on the propagation of the state. Further, we can obtain an impossible differential distinguisher for an arbitrary number of rounds of Shadow. Finally, we perform a full key recovery attack on the full-round Shadow-32 and Shadow-64. Both experimentally and theoretically, our results indicate that Shadow is critically flawed, and regardless of the security strength of the internal components and the number of rounds applied, the overall cipher remains vulnerable to impossible differential cryptanalysis. [ABSTRACT FROM AUTHOR]

This is a review on recent results on the equations of motion for light rays in a non-magnetised pressure-free plasma on a general-relativistic spacetime. Under the assumption that both the spacetime metric and the plasma density are stationary and axisymmetric, the necessary and sufficient conditions are given for the existence of a (generalised) Carter constant. It is shown how, if these conditions are satisfied, the shadows of a Kerr black hole and of a Schwarzschild black hole can be calculated in a plasma. An example is given for an axisymmetric and static plasma on the Schwarzschild spacetime where circular light rays off the equatorial plane exist. [ABSTRACT FROM AUTHOR]

Sufis used fine arts to convey sufi wisdom in which words were insufficient and thus tried to convey their thoughts in a way people could understand. The impressiveness of the works of art built with sufi thought increased and these works found the opportunity to spread to a wider area. Sufis interpreted the shadow play, one of the famous traditional Turkish arts, and evaluated the materials as tools for conveying sufi thought. The culture from which the play originated and whether sufism played a role in its origins are still controversial matters. However, the fact that some narrations on the origin of shadow play in Anatolia are based on a sufi named Shaykh Küşterī is one of the elements that point to the fundamental unity of sufism and shadow play in this geography. The aim of this study, revealing sufis’ evaluations of the existence of the universe and the functionality of the shadow play in expressing sufi thought, based on the shadow play. There seem to be many sufi elements in the shadow play both structurally and in the curtain ghazals (perde gazel) in the play. In the ghazals sufi elements are worth being the subject of a voluminous study. Not only the narrations about the origin of the play, but also the sufi elements in the ghazals show how sufi thought played an active role in the shadow play. In the introduction, the origin of the shadow play, Shaykh Küşterī, and the historical and sufi personalities of Hajivat and Karagöz, who are the main characters of the play, have been analyzed. The relations of the names mentioned above with sufi circles will contribute to understanding the influence of sufi thought on the play. Sufi evaluations of the shadow play are included in the main text. The explanations of Ibn al-’Arabī (d. 638/1240) and Mawlānā Jalāl al-Dīn Rūmī (d. 672/1273) on the metaphors of shadow and light, which are the essential elements of the play, have been dealt with, and the importance of these concepts in the mentioned the sufi understanding of existence has been analyzed. In the last part of this study, I try to explain the concepts that sufis use to express their understanding of existence, their equivalents in shadow play and the sufi structure of shadow play. [ABSTRACT FROM AUTHOR]

In this article, we address the critical role of illumination in visual positioning and propose an illumination augmentation scheme to improve positioning accuracy under various illumination conditions. We use pix2pix GAN to train various illumination models that generate illumination images for 3D objects. These images are then used to augment the training of deep learning-based visual positioning models, such as OneShot. Our experimental results demonstrate a significant improvement in the positioning accuracy of the object manipulation experiments conducted by an automated visual-servo manipulator. Illumination augmentations increased the success rate from 41 to 89% under severe illuminations and from 80 to 97% under ordinary illuminations. The proposed illumination augmentation scheme offers a practical solution for improving the visual positioning of objects in diverse and changing manufacturing environments. [ABSTRACT FROM AUTHOR]

Solar greenhouse is one of the most important horticultural facilities in China. A great contribution has been made to produce fruits and vegetables in winter in northern China. Among them, the material of the south roof is usually plastic films with high light transmittance. The heat preservation quilt can also be used with better thermal insulation performance on the south roof, in order to reduce the heat loss in the low temperature outdoor environment at night. However, artificial management cannot fully meet large-scale production, due to the time-consuming and laborious in the large area of heat preservation quilt. Therefore, the heat preservation quilt can be accomplished using rolling machine at present. A fixed heat preservation quilt is usually laid between the rolling machine and the covering plastic film, in order to prevent the rolling machine from damaging the covering plastic film of the south roof during actual work. Specifically, the fixed heat preservation quilt is located in the center of the east-west length of the solar greenhouse. The sunlight can be blocked into the inside solar greenhouse in the daytime. The resulting shadow can move in the solar greenhouse over time, inevitably leading to the indoor light, temperature distribution, and crop yield. In this study, a calculation model was proposed for the shadow width of the fixed heat preservation quilt, according to the theory of direct solar radiation. A series of tests were also performed on the indoor light and temperature under the fixed heat preservation quilt. The experimental solar greenhouse was selected in Hongke Farm (39.6°N, 116.0°E), Fangshan District, Beijing. The results show that the average photosynthetic photon flux density (PPFD) was 198 μmol/(m² ·s) under the fixed heat preservation quilt. PPFD gradually increased with the center of the fixed heat preservation quilt moving on both sides. The average PPFD was greater than 400 μmol/(m² ·s) at a position greater than 3.6 m from the center of the fixed heat preservation quilt. Meanwhile, the light cumulant at the distance of 4.8 m increased by more than 130%, compared with the directly underneath fixed heat preservation quilt. In the daytime, the indoor air temperature, wall temperature and soil temperature directly below the fixed heat preservation quilt were 2.2, 5.8 and 2.3 ℃ lower than those on both sides of the quilt. Solar energy was collected and stored in the daytime, and then released heat at night, because the walls and the soil were the heat storage media. As a result, the higher temperature at night was achieved in the walls and the soil that received strong sunlight in the daytime. At night, the maximum wall temperature and the soil temperature directly below the fixed heat preservation quilt were 1.2 and 1.3 ℃ lower than those on both sides of the quilt. There was 14.3 kg average yield reduction of tomato in each furrow under the fixed heat preservation quilt, which was 36.2% than before. The average reduction of plant stem thickness was 2.0-4.0 mm. The shadow width was mainly affected by the illumination time, the geographical location, the orientation and the structure of the solar greenhouse. The shadow width decreased first and then increased over time in the daytime. The shadow width was the smallest at noon. The average shadow width of the solar greenhouse in the western region was larger than that in the eastern. Once the orientation of the solar greenhouse gradually changed from southwest to south-east, the shadow width decreased in the morning and increased in the afternoon. When the greenhouse azimuth was in range of -9° to 9°, the maximum difference of the average shadow width was less than 10.0%. Light and temperature are the important influencing factors on the normal growth of crops. Therefore, it is necessary to rationalize the management of the fixed heat preservation quilt. [ABSTRACT FROM AUTHOR]

Katona's intersection theorem states that every intersecting family F ⊆ [ n ] (k) satisfies | ∂ F | ⩾ | F | , where ∂ F = { F \ { x } : x ∈ F ∈ F } is the shadow of F . Frankl conjectured that for n > 2 k and every intersecting family F ⊆ [ n ] (k) , there is some i ∈ [ n ] such that | ∂ F (i) | ⩾ | F (i) | , where F (i) = { F \ { i } : i ∈ F ∈ F } is the link of F at i. Here, we prove this conjecture in a very strong form for n > k + 1 2 . In particular, our result implies that for any j ∈ [ k ] , there is a j-set { a 1 , ⋯ , a j } ∈ [ n ] (j) such that | ∂ F (a 1 , ⋯ , a j) | ⩾ | F (a 1 , ⋯ , a j) | . A similar statement is also obtained for cross-intersecting families. [ABSTRACT FROM AUTHOR]

In this paper, we study the dynamics of a test particle around a regular black hole (BH) in a non-minimal Einstein-Yang-Mills (EYM) theory and examine the BH shadow. The EYM theory is a non-minimally coupled theory in which curvature couples to non-Abelian gauge fields. We investigate particle motion with parameters in EYM BH for massless and massive particles. This work provides the horizon structure, photon radius and inner stable circular orbit (ISCO) of a mass particle with EYM BH parameters. An analysis is provided of the effective potential as well as the possible orbits for test particles under various EYM BH parameters values. In timelike radial geodesics, we find that for smaller values of magnetic charge, particles following a timelike radial geodesic are more hasty in EYM BH, and hence arrive at the center faster than those traveling a Schwarzschild BH geodesic. However, at larger values of the magnetic charge, the inverse effect is observed. The effect of model parameters is investigated in order to study the ISCO, photon radius, orbit stability (Lyapunov exponent), and effective force on particles for the BH in the EYM theory. Finally, we investigate the BH shadow. We find that higher magnetic charge values and non-minimal coupling parameters result in smaller shadow radius values. [ABSTRACT FROM AUTHOR]

Shadows are a special distortion in synthetic aperture radar (SAR) imaging. They often hamper proper image understanding and target recognition but also offer useful information, and therefore, the statistical modeling of SAR image shadows is imperative. In this endeavor, we systematically deduced the statistical models of shadows in multimodal SAR images, including single-look intensity and amplitude images and multilook intensity and amplitude images in a real domain and complex domain, respectively. In particular, for the filtered SAR image shadow, we introduced the generalized extreme value (GEV) distribution to characterize its statistics. We carried out an experiment on shadows in a real SAR image and conducted chi-square goodness-of-fit tests on the deduced models. Furthermore, we compared the deduced statistical models of shadows with state-of-the-art statistical models of SAR imagery. Finally, suggestions are given for selecting the optimal statistical model of shadows in multimodal SAR images. [ABSTRACT FROM AUTHOR]

The output of Solar Panels is directly dependent on the intensity of direct Sunlight that is incident on the panels. But this efficiency reduces due to shadow effects for rooftop-mounted panels. These shadows can come from other solar panels, nearby buildings, or high-rise structures. It is possible to optimize Maximum Power Point Tracker (MPPT) controllers, which draw the most power possible from PV modules by forcing them to function at the most efficient voltage to increase the output of solar panels even while they are in the shade. Thus, the MPPT analyses the output of the PV module, compares it to the voltage of the battery, and determines the best power the PV module can provide to charge the battery. It then converts that power to the optimum voltage to allow the battery to receive the maximum level of currents. Additionally, it can power a DC load linked directly to the battery. Existing shadow detection and MPPT control models are highly complex, which increases their computational requirements, thereby reducing the operating efficiency of the solar panels. This text discusses a novel Saliency Map-based low-complexity shadow detection model for Solar panels to overcome this issue. The proposed model initially extracts saliency maps from connected Solar panel configurations and evaluates the background for the presence of shadows. Based on the intensity shadows, the model tunes MPPT parameters for optimal voltage & current outputs. Due to this, the model can maximize Solar panel output by over 8.5%, even under shadows, making it useful for various real-time use cases. [ABSTRACT FROM AUTHOR]

By applying the Keeton and Petters technique, we find the deflection angle as a series expansion with a specific factor of mass. We investigate the shadow structure of a regular black hole with cosmic string with a non-magnetized, pressure-free plasma around it. In order to separate the Hamilton equation and locate the photon areas, certain plasma distributions are taken into consideration. Moreover, by utilizing a new ray-tracing technique, we analyze the photon's path around a regular black hole with cosmic string in the presence of plasma whose density depends on the radius coordinate. We also analyze the plasma effects on the shadow of black hole. We obtain an analytical formula that describes the boundary curve of the shadow for such a black hole in an expanding universe for an observer at any finite location outside the horizon. In the presence and absence of plasma, we detect deviations that are further investigated by analyzing the geometry of shadow angle at a particular value of plasma frequency. [ABSTRACT FROM AUTHOR]

The concept of border is a much-debated topic, also due to numerous planetary crises of political, economic, and religious origin. The present author supports both the usefulness and the necessity of the border qua psychological entity, insofar as its proper function allows for the process of psychological identification to occur. Moreover, the speed of major socio-cultural changes characterising the contemporary era is argued to be compromising the dynamic psychological balance between growth and transformation, whilst providing the illusion of the psyche as an undifferentiated whole.

Considering solar gain through the window (SGW), this study investigated the effects of installing shading on cooling load. Approving energy analysis for the base building (without shading), the cooling, heating, and annual energy demand were calculated. The best window angle and the best shading projection were obtained using the genetic algorithm. For the yearly minimum energy demand scenario, it was found that the window should be placed in the south direction, accompanied by the shading project with a maximum length of 20 cm. The results of the genetic algorithm revealed that for windows at the angle of 75–90°, the positive shading effects on annual energy demand become maximum. In this case, the shading reduces the yearly energy consumption by 3.1 %. The optimization showed that the shades have the best results for reducing the cold load for windows that are located in the azimuth angle between 135 and 180 °.

AbstractScott Robert Gillam says: The contrast in the visual field is the basis of the visual perception of things that fall within our field of vision, when we perceive the shape of the form, this means that there must be differences in the visible field, and wherever there are differences there must be some contrast, and this is The basis of visual perception of different bodies. (Scott 1968)The visual arts, whether they are two-dimensional such as photographic works, or three-dimensional works such as sculpture and architecture - when they are located in our visual fields, they awaken our visual senses and push them to pay attention to the light waves coming from reflective surfaces of all kinds. Immediately, our sensory organs, nervous system, and brain centers are alerted, and eventually respond to these influences.Light has proven that it was and still is one of the most important elements of the drama of formation for the art of photography, and the transition from one artistic era to another was contingent on changing the form and content of light as an advanced plastic element from one image to another. Methods and evolution of performance methods.In fact, light and shadow, with their special capabilities, had a direct impact on the various photographers who controlled the different forces between light and shadow and were able to adapt them to serve their artistic goals, and their own ideas.It is worth mentioning that the basis of (my pictorial concept), which dominates my paintings with this artistic experience, is focused on the dramatic value of both light and shadow within my artwork, which was not known before in my previous artistic experiences,And I hope that I have succeeded in my attempt to achieve the dramatic value within my artistic experience paintings

Light availability and distribution play an important role in every ecosystem as these affect a variety of ecosystem processes and functions. To estimate light availability and distribution, light simulations can be used. Many previous models were based on highly simplified tree models and geometrical assumptions about tree form, or were sophisticated and computationally demanding models based on 3D data which had to be acquired in every season to be simulated. The aim of this study was to model the shadow cast by individual trees at high spatial and temporal resolution without the need for repeated data collection during multiple seasons. For our approach, we captured trees under leaf-off conditions using terrestrial laser scanning and simulated leaf-on conditions for individual trees over the remainder of the year. The model was validated against light measurements (n=20,436) collected using 60 quantum sensors underneath an apple tree (Malus domestica Borkh.) on a sunny and cloudless summer day. On this day, the leaves and the shadow were simulated with a high spatial (1 cm) and temporal resolution (1 min). The simulated values were highly correlated with the measured radiation at r=0.84. Additionally, we simulated the radiation for a whole year for the sample apple tree (tree height: 6.6 m, crown width: 7.6 m) with a resolution of 10 cm and a temporal resolution of 10 min. Below the tree, an area of 49.55 m² is exposed to a radiation reduction of at least 10%, 17.74 m² to at least 20% and only 0.12 m² to at least 30%. The model could be further improved by incorporating branch growth, curved leaf surfaces, and gravity to take the weight of the foliage into account. The presented approach offers a high potential for modelling the light availability in the surroundings of trees with an unprecedented spatial and temporal resolution.

The general subject of this analysis is the presence of myths on social media, a heritage of the previous century’s mass culture, and in particular, for social movements. Social movements within networked communication are particularly endowed with mythologies, which draw on mass culture and on societies’ archetypal and psychological backgrounds. This fact justifies the hypothesis that the most effective and popular social movements resort to deeper mythological forms. The specific objective is to describe concrete myths in the language of digital social movements and to review the aspects of mythology in the scholarly literature on mythology from four fields. After tracing contents and impact, a qualitative analysis, focused on two examples justified by their digital origin, is performed: the “Anonymous” movement and “Je Suis Charlie” social mobilisation. Results show the persistence of two mythological motives: the profound hero’s monomyth, playing an essential identifying role, channelled through social networks, with hashtags as slogans, and the related myth of the shadow, the dark, “Anonymous” and hybrid identity. Connections and analogies with other recent examples are discussed ?such as the “Me Too” and “Black Lives Matter” cases?. The conclusion is the clear connection between these two myths and the communicative strength of social movements transmitted through social networks.El tema general de este análisis es la presencia de los mitos en las redes sociales, herencia de la cultura de masas del siglo anterior y en particular, en los movimientos sociales. Los movimientos sociales en las redes digitales se dotan de mitologías, sean retomadas del siglo anterior sean formas del fondo arquetípico y psicológico intemporal. Esta presencia justifica la hipótesis sobre si los movimientos más eficaces y populares recurren a formas mitológicas más profundas. El objetivo específico es describir mitos concretos que aparezcan en el lenguaje de los movimientos sociales específicamente digitales. Se revisan los rasgos de los mitos de acuerdo con los autores más prestigiosos de cuatro ámbitos científicos. Se extraen del rastreo de contenido e impacto dos ejemplos de origen digital: el movimiento «Anonymous» y la movilización social «Je Suis Charlie». Aplicando análisis heurístico, los resultados muestran la persistencia de dos motivos mitológicos muy concretos: el profundo monomito del héroe, que cumple un papel crucial identificativo en las canalizaciones mediante redes como Twitter, a partir del uso específico de los hashtags como eslóganes, y el mito asociado de la sombra, la identidad anónima, híbrida y oscura. Se presentan las funciones y analogías en otros movimientos recientes –como «Me Too» y «Black Lives Matter»–. Se concluye la conexión entre estos mitos y la fuerza comunicativa de los movimientos sociales que se transmiten en las redes.

This study aims to empirically study the effects of the allocation, distribution, and stabilization variables on the shadow economy and their impact on tax revenues. This research is descriptive-explorative and explanatory research. The research location is at the PKL Center, Jl. Fort Pancasila City of Mojokerto. The population of 369 with the Slovin tolerance formula of 0.01 was determined as a sample of 79 respondents. Data collection uses a questionnaire; data analysis is assisted by SmartPLS software version 3.3.7. The results show: 1) Allocations have a significant effect on the shadow economy; 2) Distribution has a significant effect on the shadow economy; 3) Stabilization has no effect on the shadow economy; 4) Allocations do not affect tax revenues; 5) Distribution has a significant effect on tax revenues; 6) Stabilization has a significant effect on tax revenues; 7) Shadow economy has a significant effect on tax revenues; 8) Allocations have an indirect effect on tax revenues through the shadow economy; 9) Distribution has an indirect effect on tax revenues through the shadow economy; 10) Stabilization has an indirect effect on tax revenues through the shadow economy.

The article illustrates the potential of shadow theatre for training purposes by describing, from the perspective of artistic creation, a particular experience of collaboration between a Swiss music conservatory and an Italian theatre company. This is an unusual experience because it is linked to an acting course for voice students undergoing further training. In contemporary opera productions, actions and gestures are almost as important as the voices. To give the students as concrete a stage experience as possible, the use of shadow theatre, inspired by the Jungian metaphor of the unconscious and the unspoken, allows a layering of different levels of approach: vocal, emotional, stage and character building. Musically, the choice of combining different repertoires, such as baroque and contemporary, was useful to stimulate reflection on the use of the voice and to explore unexpected sounds and depths. The shadows, together with a scenography function, were the means to represent concepts and sensations such as the double, the forms of the unconscious, the labyrinths of desire and the traces of dreams. The three editions of the project, each consisting of a week of rehearsals and a public performance, took place in 2015, 2016 and 2019.

Graphs (i.e., networks) have become an integral tool for the representation and analysis of relational data. Advances in data gathering have led to multi-relational data sets which exhibit greater depth and scope. In certain cases, this data can be modeled using a hypergraph. However, in practice analysts typically reduce the dimensionality of the data (whether consciously or otherwise) to accommodate a traditional graph model. In recent years spectral hypergraph theory has emerged to study the eigenpairs of the adjacency hypermatrix of a uniform hypergraph. We show how analyzing multi-relational data, via a hypermatrix associated to the aforementioned hypergraph, can lead to conclusions different from those when the data is projected down to its co-occurrence matrix. To this end we consider how the principal eigenvector of a hypergraph and its shadow can vary in terms of their spectral rankings, Pearson/Spearman correlation coefficient, and Chebyshev distance. In particular, we provide an example of a uniform hypergraph where the most central vertex (à la eigencentrality) changes depending on the order of the associated matrix. To the best of our knowledge this is the first known hypergraph to exhibit this property. We further show that the aforementioned eigenvectors have a high Pearson correlation but are uncorrelated under the Spearman correlation coefficient. [ABSTRACT FROM AUTHOR]

This paper enquires into the relationship between the rigorous graphic construction of penumbra and shadow and the idea of a developable surface circumscribed to two cores (whether these are curves or surfaces). The first rigorously constructed graphic representations of shadow and penumbra appearing in different historical treatises are contextualised and contrasted with the first works addressing the mathematical description of such surfaces. We describe how artisans and artists have employed physical and mechanical models to construct circumscribed developable surfaces, examining both their formal exploration and constructive formalisation. Next we extrapolate the mechanisms for generating circumscribed surfaces to digital and parametric models. The two procedures presented here evince the existing geometric limits of this way of generating a surface, thus influencing its constructive applications. Lastly, several examples of ephemeral architecture based on such procedures are offered, in which the digital design and manufacturing of experimental pavilions with circumscribed developable surfaces are addressed. [ABSTRACT FROM AUTHOR]

In this paper, we exhibit analytical solutions for the evolution of the mass of an astrophysical object accreting cosmic fluid according to the Bondi–Hoyle–Lyttleton mechanism. The key assumption of this model is that the adiabatic speed of sound within the accreted fluid directly affects the rate of change of the mass of the accreting object. We consider different literature equations of state, as the (Modified) Berthelot, Logotropic, generalized polytropic of index n, and quadratic models. We assume the fluid to evolve either according to General Relativity or to the Randall-Sundrum type 1 gravity model far away from the astrophysical object in an asymptotically Friedman universe. We claim that this accretion mechanism is unlikely to affect the mass-radius relationship of the photon sphere beyond the Schwarzschild one at the present time, and that the critical point of accretion in the (Modified) Berthelot fluid flow is hidden by the event horizon. Our work belongs to the broader research line investigating the interplay of small-scale and large-scale Physics in the modeling of gravitational phenomena. [ABSTRACT FROM AUTHOR]

The purpose of the article. It analyzes the components that influence the creation of movie images. Set the role of lighting in the shooting of an audiovisual product. Identify features and fragments when working with it. Prove the importance of the ability to use light sources in natural and pavilion locations. Identify the factors that affect the quality of the visual material. Research methodology. Such methods were used in the article: theoretical – analysis of movies, and publications; generalization – the influence of lighting on the quality of visual material; determination of interdependence (light, time of day and auxiliary objects that influence the creation of a frame); empirical – systematization of one’s own experience, determination of the relationship between lighting and the quality of visual material. Scientific novelty. The components that influence the creation of a visual image were analyzed for the first time, a detailed analysis of the dependence of the time of day and illumination in the field, which forms the illumination scheme, by means of theoretical analysis of films, the factors that influence the quality of the visual material are determined. Conclusions. In the course of the article, the main techniques of cinematography when creating audiovisual works are analyzed. The concepts of frame composition and the skill of conveying an emotional state are considered. The use of various lighting sources in natural and artificial locations is considered in detail. Based on the analysis of audiovisual products of leading masters, the importance of the ability to use different types of lighting sources has been proven. A list of the features and difficulties of using different types of lighting has been created and the key factors that have a direct impact on the quality of creating an audiovisual work have been outlined.

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