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3D reconstruction and 2D observation were conducted to characterize the microstructure of the castings produced through high pressure die casting with different parameters. Our results indicate that shrinkage pores generally co-existed with externally solidified crystals (ESCs). In specimen produced without fast slow shot speed, big net-shrinkage pores accompanied with ESCs were found in the center of the specimen. When the casting pressurization was introduced, the shrinkage pores gathered to the specimen center and became much less due to the optimization of melt feeding. Much more porosity was found near the gate rather than in the middle of the rod bar, especially gas pores. The filling process simulation reveals that the middle position of the bars was firstly filled and followed by the near gate position accompanied with one intense turbulent flow.

Through quantitative statistics and morphological characterization of ceramic fragments for ceramic composite bulletproof insert plates (CCBIPs), distribution characteristics of ceramic fragments within a specific size range were analyzed for different Armor Piercing Incendiary (API) and shot times. To quantitatively evaluate the effect of energy absorption for ceramic plates, a model of energy absorption during penetration for CCBIPs was established based on statistics of the size distribution of ceramic fragments (SDCF). Variation in the SDCF and its influence on energy absorption for CCBIPs were investigated. The results indicate that the distribution feature of ceramic fragments in the range of 0.25–2.25 mm is Gaussian distribution. Compared with Type 56 of API (56-API), ceramic fragments formed by 53-API with higher kinetic energy possess more quantity and more concentrated distribution, whose average equivalence size decreases by 6.5%, corresponding to increasing by 83.9% of estimated energy absorption. Besides, the ability of CCBIPs to resist the third shot is significantly weakened, whose estimated energy absorption decreases by 58.8% compared with the first shot. More concentrated distribution and fewer fragments are formed after the third shot, the average equivalence size of ceramic fragments increases by 6.9%, which may attribute to the micro-cracks induced by the previous two shots.

I measure the impact of rarity on price. The main challenge is that usually rarity is positively correlated with quality. In addition, sometimes price also affects rarity. To overcome these difficulties, I study an NBA digital collectibles market called NBA Top Shot where those concerns are well addressed. By analyzing novel and rich data sets, I find that the elasticity of price with respect to circulation is -0.74 on average. I also find that less popular products are more elastic than more popular products are.

In the early hours of June 8, 2017, a Weis Market employee in Tunkhannock, Pennsylvania, shot three co-workers and herself. Shortly before the shooting, the perpetrator uploaded vast amounts of dig...

In this study, the liquefied petroleum gas (LPG) accident in Wenling, Zhejiang Province, China, on June 13, 2020, was analyzed and simulated. An LPG tank truck overturned and collided with the concrete guardrail; the subsequent explosion of the tank released 25.36 t LPG. Shortly afterward, the LPG tank was shot into the air, and the gas cloud ignited, thereby triggering a fire and vapor cloud explosion (VCE). This accident killed 20 people, injured 175 people, and caused significant property loss. The accident timeline was established based on multiple accident images, and the accident process was discussed in detail. The distribution of tank debris, evaporation and spreading of the LPG pool, dispersion of the LPG gas cloud, and VCE were simulated with the EFFECTS and ALOHA software. The images of the accident scene helped to determine and analyze the accident process. In the particular case in which a tank is shot into the air with a continuous two-phase jet, the actual flight distance of the tank is much greater than the prediction of the debris distribution model. The gas cloud distribution simulated with the SLAB model approximately corresponds to a major part of the severely damaged zone. In this accident, the TNO multi-energy method and ALOHA provide relatively consistent predictions with the actual building damage distribution when models use a specific confined explosive mass.

The inverse problem of determining how to shot peen a plate such that it deforms into the desired target shape is a challenge in the peen forming industry. While peening thick plates uniformly on one side results in a spherical shape, with the same curvature in all directions, complex peening patterns are required to form other shapes, such as cylinders and saddles found on fuselages and wing skin panels. In this study, we present an optimization procedure to automatically compute shot peening patterns. This procedure relies on an idealized model of the peen forming process, where the effect of the treatment is modeled by in-plane expansion of the peened areas, and on an off-the-shelf optimization algorithm. For validation purposes, we peen formed three 305 × 305 × 4.9 mm and two 762 × 762 × 4.9 mm 2024–T3 aluminium alloy plates into cylindrical and saddle shapes using the same peening treatment. The obtained shapes qualitatively match simulations. For 305 × 305 × 4.9 mm plates, the relative differences had the same distribution and were of the same order of magnitude as initial out-of-plane deviations measured on the as-received plates.

Federated Learning (FL) has been drawing significant attention from both academia and industry working on distributed machine learning. In practice, learning over mutually isolated datasets residing at the network edge, also known as silos, FL clients can suffer from a lack of samples, due to many reasons (e.g., expensive annotation), and this has potentially significant negative impact on FL performance. Few-Shot Learning (FSL) has been considered as a promising solution, but unfortunately cannot be directly applied to practical Cross-Silo Federated Learning (CSFL) systems. In this article, as far as we know, we conduct the first systematic discussion of the specific challenges of FSL in CSFL systems. We extract essential design issues found in Federated Few-Shot Learning (FFSL), and develop a new FFSL method based on Model-Agnostic Meta Learning (MAML). Through experiments using real-world federated datasets, we comprehensively demonstrate our method's advantages over existing FL and FSL methods in different practical CSFL scenarios where hitherto FL and FSL methods failed. We also highlight some promising future research directions.

Few-shot text classification aims to learn a classifier from very few labeled text data. Existing studies on this topic mainly adopt prototypical networks and focus on interactive information between support set and query instances to learn generalized class prototypes. However, in the process of encoding, these methods only pay attention to the matching information between support set and query instances, and ignore much useful information about intra-class similarity and inter-class dissimilarity between all support samples. Therefore, in this paper we propose a negative-supervised capsule graph neural network (NSCGNN) which explicitly takes use of the similarity and dissimilarity between samples to make the text representations of the same type closer with each other and the ones of different types farther away, leading to representative and discriminative class prototypes. We firstly construct a graph to obtain text representations in the form of node capsules, where both intra-cluster similarity and inter-cluster dissimilarity between all samples are explored with information aggregation and negative supervision. Then, in order to induce generalized class prototypes based on those node capsules obtained from graph neural network, the dynamic routing algorithm is utilized in our model. Experimental results demonstrate the effectiveness of our proposed NSCGNN model, which outperforms existing few-shot approaches on three benchmark datasets.

Shot-hole disease (SH) is one of the most common and important diseases affecting flowering cherry (FC; Prunus × yedoensis Matsumura; Somei-yoshino) trees in South Korea every year, resulting in premature defoliation and reduced flowering in the following year. However, pathogens associated with the disease remain unknown, which has rendered disease management challenging. Here, the pathogens associated with SH, their biochemical characteristics, and their host range were elucidated. Detached-leaf and in planta assays revealed that two biofilm-forming bacteria—namely, Burkholderia contaminans and Pseudomonas syringae pv. syringae—caused SH of FC trees. These pathogens were recorded for the first time as the causes of SH of FC trees in South Korea. Additionally, the two pathogens induced similar disease symptoms in several stone fruit belonging to the genus Prunus, including peach (Prunus persica), plum (P. salicina), and apricot (P. mume), with peach being the most susceptible. These results indicate that B. contaminans and P. syringae pv. syringae caused SH on FC trees and presented a broad spectrum of hosts. Furthermore, Xanthomonas arboricola pv. pruni, the causative agent of leaf spot on stone fruit, incited brown spots and shot holes on FC leaves. Therefore, FC trees are susceptible to infections by various pathogenic bacteria, including B. contaminans, P. syringae pv. syringae, and X. arboricola pv. pruni. These findings will be of great importance as a reference for effective management of SH in the face of possible cross-infection between Prunus spp. in the future.

We propose a new, more actionable view of neural network interpretability and data analysis by leveraging the remarkable matching effectiveness of representations derived from deep networks, guided by an approach for class-conditional feature detection. The decomposition of the filter-n-gram interactions of a convolutional neural network (CNN) and a linear layer over a pre-trained deep network yields a strong binary sequence labeler, with flexibility in producing predictions at—and defining loss functions for—varying label granularities, from the fully supervised sequence labeling setting to the challenging zero-shot sequence labeling setting, in which we seek token-level predictions but only have document-level labels for training. From this sequence-labeling layer we derive dense representations of the input that can then be matched to instances from training, or a support set with known labels. Such introspection with inference-time decision rules provides a means, in some settings, of making local updates to the model by altering the labels or instances in the support set without re-training the full model. Finally, we construct a particular K-nearest neighbors (K-NN) model from matched exemplar representations that approximates the original model’s predictions and is at least as effective a predictor with respect to the ground-truth labels. This additionally yields interpretable heuristics at the token level for determining when predictions are less likely to be reliable, and for screening input dissimilar to the support set. In effect, we show that we can transform the deep network into a simple weighting over exemplars and associated labels, yielding an introspectable—and modestly updatable—version of the original model.

Few‐shot knowledge graph (KG) reasoning is the main focus in the field of knowledge graph reasoning. In order to expand the application fields of the knowledge graph, a large number of studies are based on a large number of training samples. However, we have learnt that there are actually many missing relationships or entities in the knowledge graph, and in most cases, there are not many training instances when implementing new relationships. To tackle it, in this study, the authors aim to predict a new entity given few reference instances, even only one training instance. A few‐shot learning framework based on a hybrid attention mechanism is proposed. The framework employs traditional embedding models to extract knowledge, and uses an attenuated attention network and a self‐attention mechanism to obtain the hidden attributes of entities. Thus, it can learn a matching metric by considering both the learnt embeddings and one‐hop graph structures. The experimental results present that the model has achieved significant performance improvements on the NELL‐One and Wiki‐One datasets.

The detailed study presented herein of gelatins modified with tannins as greener binder systems for stone wool and related materials has unveiled a versatile technology that offers a wide range of possibilities for tailor-making properties toward various application areas. Thus, high unaged and aged mechanical strengths in combination with low water solubilities may generally be obtained from the use of gelatins with higher gel strength (and hence, generally, higher molecular weights), low-to-mid range tannin addition levels (3–20%), alkali metal hydroxides for pH adjustment, and final pH in the range 8–9. Comparatively low water uptake properties may be obtained using higher gel strength type A gelatins, lower tannin addition levels, alkali metal hydroxides for pH adjustment, and lower final pH. Even lower water uptake properties may then be obtained using Ca(OH)2 in place of alkali metal hydroxides. If desired, higher water uptakes may be obtained using type B gelatins (or lower gel strength gelatins in general), higher tannin addition levels, and higher final pH. Mechanistic studies indicated that the optimal modification of gelatin with the tannin component occurs via several pathways.

In light of police violence and injustice, criminologists tend to focus on masculine and violent police cultures, the lack of democratic oversight and on social processes of dehumanization. Yet much less attention, however, is given to the objects commonly used in violent and lethal police encounters: guns. Drawing on long-term ethnographic fieldwork with police officers in Miami, I suggest that police officers tend to re-contextualize police gun violence in terms of individual liability and legal culpability—as a question of what constitutes a legal shot. While a legal framing might protect police officers from prosecution, the legal shot first and foremost enables state institutions to explain police brutality as “incidents”: as unintentional and exceptional outcomes of an otherwise warranted form of policing. Recognizing how the legal shot attunes our attention to individual misconduct and legal solutions to systemic and racialized police violence, I suggest, is an important step in exploring the possibilities to disarm the police, and to organize around the question of how to imagine and push for a more inclusive form of public safety.

Features of the simulation of the thermodynamic and gasdynamic processes occurring in devices for reducing the noise level of a shot from a gun were considered. A simulation of large vortices in the nonstationary turbulent flow of powder gases in a muzzle noise reduction device with a silencer representing a shaped channel with several chambers, whose volumes decrease in the direction to the silencer outlet, has been performed. Results of qualitative and quantitative investigations of the initiation, development, and damping of the shock waves in the flow of powder gases, formed as a result of the firing of a shot made from a signal gun, are presented.

In august, the summer Olympics wrapped up after a year’s delay due to the pandemic. The games featured reminders that we live in interesting times. A shot cracked at the start of each event, while we in the audience focused on the competitors’ performance. In the background, we heard the muted cheers of attendees and gazed at eerie stadiums full of empty seats.

This paper examined bending fatigue strength of shot-peened spring steel under the high cycle fatigue (HCF) and very high cycle fatigue (VHCF), and analyzed the effects of shot-peening on the high strength spring steel through service life. Hourglass shape specimens made of spring steel (Si-Cr alloys) were prepared for the rotary bending fatigue test. Actual local stresses were quantitatively calculated to compensate for the applied stress amplitudes, through which it was clarified that the shot-peening had strongly positive effects on the HCF strength, but rather negative effect on the VHCF strength. The fracturing process examination confirmed that most fish-eye fractures arose at sites deeper than the compressive residual stress zone, which did not prevent the creation of the fish-eye. The fatigue strength improvement in the VHCF range was scarcely expected as a result of the shot-peening treatment.

This article reveals the phenomenon of multilayer of the television screen space, updated in the 21st century thanks to creative methods and technical means related to the information era. The relevance of the topic under study is based on the permanent changeability of the technologies for creating visual constructs on the screen. The author traces the evolution of the original techniques of supplementing the composition of the shot in a historical context: from the classical caption to the artistic and expressive computer embodiment of graphic or other visual objects, including a simulacrum, corresponding to the properties of the concept of “additional visuals”. During the study, a rigorous analysis of the screen space is carried out when additional visuals pass into the status of augmented reality. In the view of studying the visual component of the television footage, the article draws close attention to the extra-spatial nature of the objects of the expressive compositional structure of the frame, and the variety of presentation of the composition components in the context of the multivisuality of the screen. The vertical frame composition is another subject of this study related to the use of mobile devices with video recording function. The article provides examples of using smartphones with a vertically located screen in video shooting, taking into account not only convenience, but also changes in the visual range, concentrated audience perception of the content. The filling of the screen space reveals new aspects in the construction of multi-valued compositions of the frame. Against this background, further developments in the research field of additional visuals on the television screen are very important. In this regard, this publication may be of interest to specialists in the field of media, as well as a wide range of readers and viewers.

The article discusses the history of the Stealth aircraft creation. The destruction of the F117A stealth aircraft in Yugoslavia, carried out with the participation of Soviet specialists and technologies, is described for the first time. The article analyzes the capabilities of VHF radar stations for the stealthy targets reconnaissance and for the improvement of the air defence forward edge information and control subsystem.

Previous deep learning methods usually required large‐scale annotated data, which is computationally exhaustive and unrealistic in certain scenarios. Therefore, few‐shot learning, where only a few annotated training images are available for training, has attracted increasing attention these days, showing huge potential in practical applications, such as portable equipment or security inspection, and so on. However, current few‐shot learning methods usually neglect the valuable semantic correlations between samples, thereby failing in extracting discriminating relations to achieve accurate predictive results. In this work, extending on a recent state‐of‐the‐art few‐shot learning method, transductive relation‐propagation network (TRPN), which considers the correlations between training samples, a constrained relation‐propagation network is proposed to further regularise the distilled correlations and thus achieve favourable few‐shot classification performance. The proposed framework contains three main components, namely preprocess module, relational propagation module, and relation constraint module. First, sample features are extracted and a relation graph node is constructed by treating the relation of each support–query pair as a graph node in the preprocess module. After that, in the relation propagation module (RPM), the valuable information of support–query pairs is modelled and propagated to directly generate the relational representations for further prediction. Then, a relation constraint module is introduced to regularise the relational representations and make it consistent with the ground‐truth relations as much as possible. With the guidance of the effective RPM and relation constraint module, the relational representations of the support–query pairs are distinguishable and thus can achieve accurate predictive results. Comprehensive experiments conducted on widely used benchmarks validate the effectiveness of our method compared to state‐of‐the‐art few‐shot classification approaches.

The possibility of increasing the complex of physical, mechanical and operational properties of plasma sprayed coatings from powders of the PG-19M-01 and PRH18N9 grades due to the electric pulse effect on the heterophase high-temperature flow during spraying and next surface plastic deformation of the deposited coatings by shot blasting has been investigated. It is shown that shot blasting provides the formation of a hardening layer with a thickness of up to 180...200 μm, while the maximum level of microhardness is observed at a depth of about 60 μm. The microhardness of the coating from PG-19M-01 powder at the point of maximum hardening increases by 35%; steel coatings from PR-H18N9 powder – by 48% compared to the state after spraying. Experimental studies of the effect of this treatment on the bond strength and wear resistance of the obtained coatings have been carried out. It is shown that after shot-blasting the bond strength of the coatings decreases by 10...15%, and the wear resistance increases by 32...38%.

Em 1966, Florença foi invadida por 80 a 250 milhões de metros cúbicos de água, que arrastaram 30 mil carros e arrasaram casas, lojas, monumentos, chegando em alguns locais a sete metros de altura. A catástrofe destruiu mais de 1.500 obras de arte e um milhão de manuscritos preciosos e livros raros. O cineasta florentino Franco Zeffirelli, que trabalhava na TV RAI, conseguiu chegar à cidade ilhada e ali rodou o impressionante documentário Per Firenze (1966), que, graças ao senador americano Edward Kennedy, rodou o mundo, mobilizando a juventude de vários países a acorrer para Florença para salvar o patrimônio da humanidade. Os assim chamados “Anjos da Lama” anteciparam os jovens que, dois anos depois, se rebelariam em todo o mundo.

PURPOSE The purpose of this study is to examine the goalkeeper’s area of defense and how the range varies depending on the relative position of the goal, goalkeeper, and ball in a 9-meter jump shot during handball matches.METHODS Data was collected from seven qualifying divisions in mens handball from the 99th National Sports Festival in Korea. A total of 231, 9-meter jump shots were analyzed with the goalkeeper‘s area of defense measured from the point the ball left the shooter’s hand and calculated based on the relative position of the goal, goalkeeper, and ball. Video analysis was conducted using the Kwon3D 3.01 program and three-dimensional coordinates calculated using the DLT method.RESULTS First, dimension of handball goals measure 3m wide and 2m high, however, results show that goalkeeper’s actual area of defense was narrower than the width of the goal posts, while vertically, area exceeded the height of the cross bar. Second, if the goalkeeper defended the striker’s shot from the side rather than from the front, the goalkeeper’s defense range was higher for the opposite side of the goal post than the near side of the goal post.CONCLUSIONS Key factors influencing goalkeeper’s area of defense include height of shot and position of goalkeeper. Results also indicate that vertical movements are more important than horizontal movements for goalkeepers in handball thus such implementation in training may lead to performance enhancement.

An integrated DEM-FEM coupling simulation approach is developed to simulate the real process of shot peening, and is validated by comparing the predicted in-depth residual stresses with the experimentally measured results. Two kinds of three-dimensional finite element models associated with the original surface roughness of Rα0 = 26.7μm and 50.1μm are respectively established by using Gaussian distribution in conjunction with the exponential autocorrelation function, and another target model without the original surface roughness is utilized for reference purposes. Taking advantage of the integrated DEM-FEM coupling simulations of shot peening processes based on the three kinds of target models, the effects of the original surface roughness, shot impact angle, and shot peening coverage on the shot-peened residual stresses and surface roughness are investigated in detail. The obtained results show that the larger original surface roughness of TC4 titanium alloy could be reduced by shot peening, and the reduction increases with the increasing shot peening coverage from 100 to 200%. In the target models associated with the original surface roughness, the distributions of shot-peened surface residual stresses tend to be more uniform than that in the target model without the original surface roughness, whereas both the in-depth residual stresses and surface roughness are not very sensitive to the changes of shot impact angle in the range from 60° to 90°.

This work introduces a novel data augmentation method for few-shot website fingerprinting (WF) attack where only a handful of training samples per website are available for deep learning model optimization. Moving beyond earlier WF methods relying on manually-engineered feature representations, more advanced deep learning alternatives demonstrate that learning feature representations automatically from training data is superior. Nonetheless, this advantage is subject to an unrealistic assumption that there exist many training samples per website, which otherwise will disappear. To address this, we introduce a model-agnostic, efficient, and harmonious data augmentation (HDA) method that can improve deep WF attacking methods significantly. HDA involves both intrasample and intersample data transformations that can be used in a harmonious manner to expand a tiny training dataset to an arbitrarily large collection, therefore effectively and explicitly addressing the intrinsic data scarcity problem. We conducted expensive experiments to validate our HDA for boosting state-of-the-art deep learning WF attack models in both closed-world and open-world attacking scenarios, at absence and presence of strong defense. For instance, in the more challenging and realistic evaluation scenario with WTF-PAD-based defense, our HDA method surpasses the previous state-of-the-art results by nearly 3% in classification accuracy in the 20-shot learning case. An earlier version of this work Chen et al. (2021) has been presented as preprint in ArXiv (https://arxiv.org/abs/2101.10063).

Peening intensity and coverage are vital measurement outputs to quantify the quality of a peening process in the surface enhancement operation of metal parts. In practice, these parameters can only be measured offline upon process completion, which is not suitable for online tracking and operation. Instead, shot stream velocity can be used as a real-time monitoring parameter to bridge operational inputs to the outputs. As such, a robust and accurate shot stream velocity model is needed for real-time tracking. In this study, we propose a blended practical model for shot stream velocity to address the issues. The model is constructed using a regression algorithm based on the blended candidate functions, which are developed from the experimental data and nature of the particle-air flow inside the system. The obtained model is validated against the experimental data for ASR 70 media type for different operating conditions of the inlet airflow pressure and media flowrate. Calculated velocities are in good agreement with the measurements. In addition, the developed model is applied to predict the shot stream velocity for ASR 230 media type, as well as to evaluate the peening intensity and coverage for different media types under different operating conditions. The predicted results are comparable to the measurement data under the same operating conditions. The maximum relative error of the predicted shot stream velocity and measurement velocity is about 5%, while the maximum error in peening intensity is about ±0.0065 mmA. Furthermore, a single-input and single-output model-based control is developed based on the proposed shot stream velocity model. The developed control system is robust, accurate, and reliable. It implies that the developed model can be used to provide the necessary information, as well as to develop the optimal process control system to improve and accelerate the peening processes for cost and time reduction of actual production.

Lead (Pb) exposure is a widespread wildlife conservation threat. Although commonly associated with Pb-based ammunition from big-game hunting, small mammals (e.g., ground squirrels) shot for recreational or pest-management purposes represent a potentially important Pb vector in agricultural regions. We measured the responses of avian scavengers to pest-shooting events and examined their Pb exposure through consumption of shot mammals. There were 3.4-fold more avian scavengers at shooting fields relative to those at fields with no recent shooting, and avian scavengers spent 1.8-fold more time feeding after recent shooting events. We isotopically labeled shot ground squirrels in the field with an enriched 15N isotope tracer; 6% of avian scavengers sampled within a 39 km radius reflected this tracer in their blood. However, 33% of the avian scavengers within the average foraging dispersal distance of nests (0.6-3.7 km) were labeled, demonstrating the importance of these shooting fields as a source of food for birds nesting in close proximity. Additionally, Pb concentrations in 48% of avian scavengers exceeded subclinical poisoning benchmarks for sensitive species (0.03-0.20 μg/g w/w), and those birds exhibited reduced δ-aminolevulinic acid dehydratase activity, indicating a biochemical effect of Pb. The use of shooting to manage small mammal pests is a common practice globally. Efforts that can reduce the use of Pb-based ammunition may lessen the negative physiological effects of Pb exposure on avian scavengers.

When studying the space path of a cloud of pellets from a shotgun and evaluating its parameters, it is advisable to have a simulation model of the optical sensor signal when a shot sheaf crosses the light screen. To create such a model, you need to get the relationship between the scale parameter in the Rayleigh distribution and the time span of the shot sheaf. Studies of the temporal distribution density of the shot sheaf span are performed, and graphs of the distribution density of the span for near-real situations are constructed. A linear dependence of the mathematical expectation of the span distribution density on the scale parameter in the Rayleigh distribution is established. A simplified expression is obtained for calculating the mathematical expectation of the time span of the shot sheaf. Statistical modeling confirmed the possibility of the practical use of the proposed formulas, including with a large number of pellets (up to 1000). The dependence of the mathematical expectation of the span on the number of pellets is investigated, its approximation by various functions is carried out, and the approximation errors are estimated. The research conducted allows us to create a simulation model of the optical sensor signal when the shot sheaf crosses the light screen on the basis of empirical data on the real-signal duration (with averaged measurement data for several shots being helpful).

Establishing effective seismic survey parameters in complex structural areas, such as salt domes, is of vital importance for accurate imaging. Shot and group intervals, maximum offset, recording time and profile length, to image the subsurface structures, are critical 2-D parameters. Geometry, aspect ratio of a recording patch and number of in-line and cross-lines are key additional parameters for 3-D seismic design. This study provides a workflow for determining optimal 2-D and 3-D seismic survey parameters as exemplified by a Texas salt dome case. The Pierce Junction oil field, in proximity to the salt dome, is located in Houston, Texas, and has been one of the most prolific hydrocarbon producers in the region. Engineered caverns in the salt dome itself are now used for fluid storage. Design parameters for the future seismic surveys are partially informed by previous seismic data shot over the structure (where the top of the salt is at about 290 m depth and overlying cap rock, 210 m). Existing 2-D seismic data, crossing the salt dome, are processed to extract the velocities of the salt, cap rock, and near-surface sediments. In the following step, 2-D and 3-D velocity models of the study area are constructed using legacy well data as well as gravity measurements which were acquired as part of this study. Synthetic shot gathers are next modeled with a finite difference method using the acoustic wave equation. To generate images of the constructed model, reverse time migration (RTM) is applied to the synthetic data. By assessing the coverage and continuity of the imaged salt boundaries using a variety of decimated input data sets, the optimal survey parameters are determined. In this case, 20 m group and 40 m shot interval, 3000 m maximum offset, and 8 km profile length with a 4 s recording time are found to be most favorable 2-D acquisition parameters. Using similar coverage and continuity criteria, group and shot intervals of a 3-D seismic survey are determined as 25 m and 50 m, respectively. The receiver and shot line intervals are chosen as 250 m in an orthogonal geometry with 33 in-lines and 33 cross-lines distributed in the 8 × 8 km2 survey area. The aspect ratio of any patch with 13 in-lines and 13 cross-lines is accepted as 1:1. This forward modeling and migration procedure, using a range of decimated data sets, can inform decisions on the final field parameters.

In this digital world, Video analysis is the most important and useful task. Currently, tremendous tasks have been done in video analysis like compressing the videos, video retrieval process and video database indexing, etc. For all these tasks, one common step is segmenting the video shots, which are referred to as Video Shots Segmentation (VSS). Video shots segmentation is used to segment the input videos into a number of frames sequentially where the scene changes occurred, i.e. called shots. In this article, segmenting the video shots follows a hybrid procedure. Here, we have introduced the moments of colors, distance metrics and threshold techniques. All the videos follow the above mentioned steps for segmenting the video shots. But, before that, the input video is converted into a specific color model i.e. YCbCr. Then, apply the color moments to extract the feature vectors of frames, which are differentiated based on the color features of frames. In every two frames of the video, distance metrics methods are applying to compute the similarity and dissimilarity of frames. And the dissimilarity of the frames can be computed by using the threshold technique to get the shots from the video. In this paper, we are using the adaptive threshold technique to segment the videos into various shots. In this step, we will get a true number of shots. By the experimental results, this proposed methodology can be evaluated with the sequence of videos based on the performance or evaluation metrics.

For firearm identification, foundational validity based on the reproducibility and persistence of characteristic marks must be established. We investigate the fired bullets of five Chinese Norinco QSZ-92 9 × 19 mm pistols over 3000 shots. The first 50 fired bullets are recovered, whereas every 50th fired bullet is recovered from the 51st to 3000th round. As such, 109 bullets are available for each pistol, and totally 545 bullets are introduced into the Evofinder® system. A large background database comprising 3000 bullets fired from 1000 registered QSZ92 9 × 19 mm pistols is used as interference. Both on-screen analysis and automatic comparison are performed. The first fired bullets from the five pistols are separately correlated with the database. The results show that although the similarity for known match bullets changes slightly as the shot number increases, the land-engraved area (LEA), groove-engraved area (GEA), and slippage marks can be reproducibly transferred to the fired bullets in consecutive shots. The Evofinder system ranks all known match bullets on the top of the correlation result with the combination of LEA, GEA, and slippage marks.

Purpose This study aims to determine the effect of the distribution of practice on learning the forehand shot in tennis. Method Twenty-four beginner tennis players participated in the study (13 males and 11 female; 8.63 ± 0.92 years old). The players were separated after groups -massed practice ( N = 12) and distributed practice ( N = 12). Each group practiced the forehand shot for 12 sessions, 4 series per session and 10 trials/series (6 weeks). The accuracy and efficacy were measured through one post-test and one retest, carried out 2 weeks after the last learning session. Results Significant improvements in accuracy between the pre-test and post-test ( p=.004) and between pre-test and re-test ( p=.006) were found in the massed practice group. Significant improvements in accuracy between the pre-test and post-test ( p=.002) and between pre-test and re-test ( p=.001) were found in the distributed practice group. No significant differences were found between groups but there was a favourable trend toward better learning in both, with improved accuracy and efficacy. Conclusion The motor learning through the distribution of practice among children has been noted, with a significant improvement in the skill acquisition of the forehand shot in the two groups. The results are useful because they clear up the doubts about how to plan the teaching of this stroke in tennis, confirming the suitability of carrying out learning programs based on massed and distributed practice.

Basketball sport originated as a non-contact sport but recently it has evolved into physically more challenging in which contact is accepted and expected. This transition of the sports has increased the injury rates substantially. Basketball includes multiple movements such as jumps, turns and change of direction, running and deceleration in its various movements of jump shot, free throw and layup shot. The complexities of these movements imposes various demands on basketball players, which makes it more important to know the health oriented aspects of the movement. This review explains the movement pattern analysis of these basketball specific movements in detail which can help the physiotherapist to plan the injury prevention strategies for their athletes. KEY WORDS: Basketball, Basketball Movements, Jump Shot, Layup Shot, Basketball Free Throw.

Heritage, a practice shot through with political forces, is mobilized by states within their international relationships through methods such as heritage diplomacy. Focusing on the connections betw...

The beginning of the COVID 19 pandemic in 2020 provided the catalyst for the development of arts based resources to assist teachers and students reengage in learning when schools reopened after loc...

Die cast alloys have to be poured at temperatures much higher than their liquidus in order to make the alloys castable. Pouring at a high temperature reduces the formation of dendrites in the shot sleeve which tend to choke the flow at the in-gate but causes increased damage to the shot tooling and dies. Forming globular grains in the shot sleeve is an effective way of breaking the limit of fluidity on reducing the pouring temperature in order to increase die life and to improve the integrity of die casting products. This study investigated the feasibility of producing globular grains in a shot sleeve using a water-cooled ultrasound trough for feeding molten metal into the shot sleeve. Globular grains were obtained using this unique trough. The temperature window within which globular grains can be produced for E380 alloy was determined. Without using the WCUST, the grains in the shot sleeve were fully dendritic and the grain size was about 300 µm. When the molten metal was poured over the WCUST, small globular grains were obtained for the entire pouring temperature window, from 610 °C (1130 °F) to 700 °C (1292 °F), tested in this study. Analysis was made on the conditions for obtaining globular grains. The analysis seems in agreement with experimental results. In addition to producing globular grains for die casting applications, the water-cooled ultrasound trough may be suitable for grain refinement of other gravity casting processes.

Shot boundary detection in videos is one of the most fundamental tasks towards content-based video retrieval and analysis. In this aspect, an efficient approach to detect abrupt and gradual transition in videos is presented. The proposed method detects the shot boundaries in videos by extracting block-based mean probability binary weight (MPBW) histogram from the normalized Kirsch magnitude frames as an amalgamation of local and global features. Abrupt transitions in videos are detected by utilizing the distance measure between consecutive MPBW histograms and employing an adaptive threshold. In the subsequent step, co-efficient of mean deviation and variance statistical measure is applied on MPBW histograms to detect gradual transitions in the video. Experiments were conducted on TRECVID 2001 and 2007 datasets to analyse and validate the proposed method. Experimental result shows significant improvement of the proposed SBD approach over some of the state-of-the-art algorithms in terms of recall, precision, and F1-score.

What does the hunting of our ancestors, armed with spears and aimed to get food, have in common with the "high tech" one practiced today for recreational purposes? Both depend on deep motivations, which Neurosciences show related to archaic brain circuits that provide thevital thrists to survival. Substances, or behaviors without biological utility, can "hook" these basic emotional circuits and lead to the attribution of new values, so that the assumption of the substance or the repetition of the behavior will becomevital, thus developing an addiction. Among them hunting, where small birds and many mammals, feeling emotions similar to ours, are shot according to what appears to be a compulsive behaviour and which could benefit from appropriate specialized therapies.

This study aims to determine the effect of arm muscle strength (X1), waist flexibility (X2), eye-hand-foot coordination (X3) and bat swing speed (X4) on the power hitting pull shot (Y) of female cricket athletes in DKI Jakarta. The research method is a survey using path analysis techniques, distributing a sample of 26 DKI Jakarta female cricket athletes. Hypothesis testing using path analysis techniques, the data obtained were analyzed by SPSS.25. This study resulted in a description of the data: a) the direct effect of X1 on Y or (r1y) = 0.330 (0.3302 x 100%); b) direct effect of X2 on Y or (r2y)= 0.306 (0.3062 x 100%); c) The direct effect of X3 on or (r3y)= 0.311% (0.3112 x 100%); d) direct effect of X4 on Y or (r4y)= 0.373 (0.3732 x 100%); e) direct effect of X1 on X4 (X1-X4) or (r14)= 0.716 (0.7162 x 100%); f) direct effect of X2 on X4 (X2-X4) or (r24) = 0.339 (0.3392 x 100%); g) direct effect of X3 on X4 (X3-X4) or (r34)= -0.094 (-0.0942 x 100%); h) indirect effect of X1 on Y through X4 (X1-X4-Y) or (r14y)= 0.716 x 0.373 = 0.267 (0.2672 x 100%); i) indirect effect of X2 on Y through X4 (X2-X4-Y) or (r24y)= 0.339 x 0.373 = 0.126 (0.1262 x 100%); j) the indirect effect of variable X3 on Y through X4 (X3-X4-Y) or (r34y) = 0.094 x 0.373 = 0.035 (0.035 x 100%). It was concluded that there was an influence of arm muscle strength, waist flexibility, eye-hand-foot coordination and bat swing speed, all of which affected the hitting pull shot power. There is an effect of arm muscle strength and waist flexibility on the swing speed of the bat. There is no effect of eye-hand-foot coordination on the swing speed of the bat. There is an indirect effect of arm muscle strength, waist flexibility and eye-hand-foot coordination on the power hitting pull shot through the speed of the bat swing. There is an indirect effect of waist flexibility and eye-hand-foot coordination on the power hitting pull shot through the swing speed of the bat.