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The anionic properties of electrolytes play a significant role in determining the electrochemical performance of VS2/SNC anodes, which is interpreted from the angle of solvation effect and corresponding electrode/electrolyte interface properties.

Nowadays X70 steel has been used as a core material for the construction of high-pressure, large-diameter and high-strength steel pipelines. The wall of piplines of an operating pipline system will deform in various degrees. Severe deformation will lead to microcracks or even a fracture. The ultrasonic flaw detection method is designed for the detection and evaluation of microcracks and defects caused by the deformation of X70 steel. However, an effective method to measure the stress level of X70 steel accurately is still lacking since the deformation of X70 steel often occurs within the elastic stage or plastic stage. Through conducting an experiment to study the tensile test of X70 steel specimens under a constant temperature, and measuring the propagation time and amplitude of ultrasonic LCR wave simultaneously to conclude the law of the propagation of ultrasonic LCR wave in elastic-plastic deformation of X70 steel, and determine the relationship between the propagation time and the amplitude of ultrasonic LCR wave and the deformation degree of X70 steel. According to the study, the deformation degree of X70 steel could be determined by the propagation time of ultrasonic LCR wave and the amplitude of the first wave: the level of stress could be calculated within the elastic stage and the deformation degree could be calculated within the plastic stage. The study results provide an effective support for the stress measurement of X70 steel by ultrasonic LCR wave.

The dynamic design of graphic language can be seen everywhere in life as the digital media era progresses. Graphic designs, such as product packaging, poster design, book binding design, and logo design, are examples of traditional visual design. The print media is the most important factor. Graphic design that is aided by digital media technology is not limited to print but also includes network media. The teaching research of China’s visual design specialty is still in its early stages, the relevant teaching system reform of various colleges and universities is still being explored, and there is no unified standard in the digital information age. As a result, it is critical to conduct in-depth research using scientific and systematic methods in order to pave the way for the development of a domestic visual design specialty in the information age. Simultaneously, the popularization and development of new media have had a significant impact on traditional printing media, breaking the monotony of traditional visual communication and making modern visual design more vivid and intuitive. Visual perception in psychology is introduced into design thinking in this paper. Apart from its expression in art culture, the concept of space also encompasses the physics concepts of time and space, as well as the scientific research theory of visual perception in psychology, which transcends the perceptual cognition level of space in art design.

In a virtual 3D city scene, a 3D building model is a must-have element. A 3D reconstruction and rendering algorithm is described in this paper. Model geometry and texture data are simplified separately using LOD model technology. Half-folded mesh algorithm is used to simplify geometric data, while wavelet algorithm is used to compress texture data. Both methods reduce the amount of data that must be stored as well as the amount of data that must be transmitted over the network. To improve the response time of the original algorithm, a Kalman filter correction algorithm is used to optimize the 3D reconstruction beam adjustment algorithm. In this paper, the experimental scheme is used to assess the method. Experiments show that the algorithm reduces the number of primitives drawn by the system while preserving the important geometric features of the scene’s building model. It can also effectively reduce the workload of drawing 3D scenes, improve computer productivity, and reduce computer hardware requirements. This technique is well suited to rendering large-scale 3D urban scenes.

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Objective To report a numerical research on the effect of a renal artery arising from false lumen (FL) on the treatment outcome of thoracic endovascular repair (TEVAR) for complicated type B aortic dissection (TBAD). Methods The original patient-specific model with the right renal artery (RRA) partially supplied by the FL (TFM) was reconstructed from its postoperative computed tomography images. Two additional models were reconstructed by artificially modifying the RRA either fully arising from the FL(CFM) or true lumen (CTM). Computational fluid dynamics (CFD) simulations were performed. Results First, for all the models, the flow splits to all the visceral arteries were much less than those of a healthy aorta. Second, the flow split to RRA in the CFM and in CTM was the least and largest respectively. Third, in TFM, the pressure gradient between the true lumen (TL) and FL was negative at the proximal FL and the entire FL was full of active blood flow. In the contrast, in CTM and CFM, the pressure differences between the two lumens remained positive and little flow was present in FL. Finally, both TL and proximal FL of this particular patient expanded and the diameters of all visceral arteries decreased at one-year follow-up. Conclusions Compared to a healthy aorta, a renal artery arising from FL following TEVAR would result in severe visceral ischemia including RA and superior mesenteric artery (SMA). In addition, our numerical simulation of the postoperative hemodynamics of this particular patient perfectly matched with its TL remodeling, FL expansion and contraction of the visceral arteries at one-year follow-up, and a patient-specific CFD simulation may be adopted to obtain information on visceral perfusion after endovascular repair for TBAD patients.

Normally entrepreneur would raise fund from angel investors during the initial round. If the venture program was by then successful, the entrepreneur would then continue the fund-raising process from venture capitalist. By adopting the convertible preferred stock, we managed to construct the two-stage angel investment decision process. This research reveals the following: (1) The probability of the first stage’s success has negative relationships with levels of priority dividend in both first and second stages, as well as with the venture capitalist’s proportion of shares. (2) The probability of the second stage’s success has negative relationships with the venture capitalist’s proportion of shares and the dividend level of both first and second stage funding. (3) There has been a threshold of dividend distribution, which belongs to angel investor. While the level of angel investor’s shares is higher than the threshold, AN would decide to join the second phase of the program; otherwise, AN would exit the project at the end of the first stage.

Background Pediatric pneumonia is the leading cause of child mortality in low-income countries. Pneumonia diagnosis is a challenge. Chest x-ray (CXR) is considered the gold standard, but it exposes children to ionizing radiation, and access to CXR is limited to hospital settings. Lung Point of Care Ultrasound (POCUS) is a portable and non-radiating alternative to CXR. Methods We enrolled 200 children aged 1-59 months from the University Teaching Hospital (UTH) Emergency Department (ED) in Lusaka, Zambia who met the WHO (World Health Organization) case definition for severe pneumonia. From each child, we collected demographic and clinical data, a CXR, and a set of ultrasound images using a Butterfly ultrasound probe. Images were independently interpreted by two radiologists blinded to the results of the other imaging modality. Using CXR as the gold standard, we determined the sensitivity and specificity, positive and negative predictive values, and likelihood ratios for pneumonia using lung POCUS. Results This preliminary analysis included 50 children seen between May-October 2020. Median age (9 months) (Range 4-15). 58% were male, (29/50). Median temperature was 37.3⁰C (range 36.5-38.0); median respiratory and pulse rates were 41 breaths/min (range 31-50) and 139 beats/min (range 124-160) respectively; median SpO2 on RA was 91% (range 89-95). 50% of cases had difficulty breathing (82%, 41/50); chest retractions (70%, 35/50) and grunting (62%, 31/50). Ultrasound images for 49/50 (98%) cases and CXRs for 50/50 (100%) of cases we analyzed. Sensitivity of lung POCUS in the detection of CAP was 61% (95% Cl: 0.52-0.84). The specificity was 77% (95% Cl: 0.56-0.91). Positive predictive value (PPV) 70% (95% CI: 0.62-0.94) and negative predictive value (NPV) 69% (95% CI: 0.56-0.79). Conclusion Preliminary findings of this study demonstrated the lower diagnostic accuracy of lung POCUS versus CXR in the detection of pneumonia in children 1- 59 months. The high specificity of the test will aid in ruling out severe pneumonia in children. Due to its availability, ease of interpretation, and absence of radiation exposure, lung POCUS should still be considered as an important initial imaging tool for the diagnosis of CAP in children in limited-resource settings. Disclosures All Authors: No reported disclosures

While visual object detection with deep learning has received much attention in the past decade, cases when heavy intra-class occlusions occur have not been studied thoroughly. In this work, we propose a Non-Maximum-Suppression (NMS) algorithm that dramatically improves the detection recall while maintaining high precision in scenes with heavy occlusions. Our NMS algorithm is derived from a novel embedding mechanism, in which the semantic and geometric features of the detected boxes are jointly exploited. The embedding makes it possible to determine whether two heavily-overlapping boxes belong to the same object in the physical world. Our approach is particularly useful for car detection and pedestrian detection in urban scenes where occlusions often happen. We show the effectiveness of our approach by creating a model called SG-Det (short for Semantics and Geometry Detection) and testing SG-Det on two widely-adopted datasets, KITTI and CityPersons for which it achieves state-of-the-art performance. Our code is available at https://github.com/ChenhongyiYang/SG-NMS.

Monitoring population-level changes in diet could be useful for education and for implementing interventions to improve health. Research has shown that data from social media sources can be used for monitoring dietary behavior. We propose a scrape-by-location methodology to create food image datasets from Instagram posts. We used it to collect 3.56 million images over a period of 20 days in March 2019. We also propose a scrape-by-keywords methodology and used it to scrape ~30,000 images and their captions of 38 Kenyan food types. We publish two datasets of 104,000 and 8,174 image/caption pairs, respectively. With the first dataset, Kenya104K, we train a Kenyan Food Classifier, called KenyanFC, to distinguish Kenyan food from non-food images posted in Kenya. We used the second dataset, KenyanFood13, to train a classifier KenyanFTR, short for Kenyan Food Type Recognizer, to recognize 13 popular food types in Kenya. The KenyanFTR is a multimodal deep neural network that can identify 13 types of Kenyan foods using both images and their corresponding captions. Experiments show that the average top-1 accuracy of KenyanFC is 99% over 10,400 tested Instagram images and of KenyanFTR is 81% over 8,174 tested data points. Ablation studies show that three of the 13 food types are particularly difficult to categorize based on image content only and that adding analysis of captions to the image analysis yields a classifier that is 9 percent points more accurate than a classifier that relies only on images. Our food trend analysis revealed that cakes and roasted meats were the most popular foods in photographs on Instagram in Kenya in March 2019., Comment: Another version of the paper was submitted to the ACM International Conference on Multimedia (ACMMM2019)

Channel coordination is an optimal state with operation of channel. For achieving channel coordination, we present a quantity discount mechanism based on a fairness preference theory. Game models of the channel discount mechanism are constructed based on the entirely rationality and self-interest. The study shows that as long as the degree of attention (parameters) of retailer to manufacturer's profit and the fairness preference coefficients (parameters) of retailers satisfy certain conditions, channel coordination can be achieved by setting a simple wholesale price and fixed costs. We also discuss the allocation method of channel coordination profit, the allocation method ensure that retailer's profit is equal to the profit of independent decision-making, and manufacturer's profit is raised.

In this paper, we propose a new structure that combines Grey Prediction with Line of Sight (GP-LOS) to predict yaw angle in order to achieve path following for autonomous underwater vehicle (AUV). The proposed structure can be described by two stages. First, we use grey prediction to predict the position coordinates of the next time. Second, taking advantage of the principles of the Line of Sight, we can obtain the desired heading in advance. Then we take the classical PID as control algorithm of AUV because it has the advantage to be easily implemented and to provide reliable control performance. The simulation results have shown that the GP-LOS can achieve the path following effectively whether straight line or curve.

When venture capital has been invested into venture companies, venture capitalists and venture entrepreneurs form a principal-agent relationship. Take into account the fact that the venture entrepreneur’s effort is a long process, because the effort is not the same at different stage. Therefore, efforts variables are seen as the multistage dynamic variable, and venture investment principal-agent model with venture entrepreneurs having multistage efforts is constructed on the basis of the classic principal-agent theory in the paper. Further, in the later stage effort of venture entrepreneurs is affected by the size of prestage benefit with venture capitalists and venture entrepreneurs; thus the fairness preference model is improved, and venture investment principal-agent model with venture entrepreneurs having multistage efforts is constructed on the basis of fairness preference theory. Both theoretical derivation and simulation have demonstrated that, under the condition of information asymmetry, if the fairness preference of venture entrepreneurs holds, then(1)venture capitalists provide venture entrepreneurs with level higher than that without fairness preference,(2)in every single stage venture entrepreneurs make efforts higher than those without fairness preference, and(3)in two periods both venture investors and venture entrepreneurs gain total real gains higher than those in two periods without fair preference.

Crack-induced changes in the aeroelastic boundaries of an unswept composite wing are investigated. The bending-torsion couplings due to the unbalanced laminates and offset of the center of gravity are incorporated into the equation of motion. The edge crack, modeled with the local flexibility concept, introduces additional boundary conditions at the crack location. The fundamental modes of the intact and cracked beam are used in Galerkin's method, and the approximate solution for flutter and divergence speeds is obtained with steady and quasi-steady aerodynamic forces applied. Changes in flutter and divergence speeds (with respect to the crack ratio and its location, along with the fiber orientation) are compared. In many cases, the existence of an edge crack imposes detrimental effects on the aeroelastic boundaries, although it may increase the flutter and/or divergence speed when fibers are orientated at certain angles. The results may help composite wing designers in their aeroelastic tailoring and structural engineers in designing damage prognosis tools to predict the health status of, composite wing structures.

The aeroelastic characteristics of a cantilevered composite panel of large aspect ratio and with an edge crack are investigated. The panel consists of several fiber-reinforced composite plies, and is modeled with a one-dimensional beam vibrating in coupled bending and torsion. The fundamental mode shapes of the cracked cantilever are used to study the interaction between a crack and aerodynamic characteristics by employing Galerkin’s method. Variation of the divergence/flutter speed with respect to the crack ratio, its location as well as the fiber angle is investigated. The divergence/flutter speed is more sensitive to the bending-torsion coupling parameter than to the presence of the crack. The crack may or may not reduce the divergence/flutter speed, depending on the fiber orientation. The qualitative analysis may help the development of an online prognosis tool for an aircraft with large aspect-ratio unswept composite wings.

The coupled bending and torsional vibration of a fiber-reinforced composite cantilever with an edge surface crack is investigated. The model is based on linear fracture mechanics, the Castigliano theorem and classical lamination theory. The crack is modeled with a local flexibility matrix such that the cantilever beam is replaced with two intact beams with the crack as the additional boundary condition. The coupling of bending and torsion can result from either the material properties or the surface crack. For the unidirectional fiber-reinforced composite, analysis indicates that changes in natural frequencies and the corresponding mode shapes depend on not only the crack location and ratio, but also the material properties (fiber orientation, fiber volume fraction). The frequency spectrum along with changes in mode shapes may help detect a possible surface crack (location and magnitude) of the composite structure, such as a high aspect ratio aircraft wing. The coupling of bending and torsion due to a surface crack may serve as a damage prognosis tool of a composite wing that is initially designed with bending and torsion decoupled by noting the effect of the crack on the flutter speed of the aircraft.

The infinity period dynamic control problem of distribution channel was studied with differential game approach. Four differential dynamic control models of coordinated channel game, uncoordinated static game, Stackelberg game with manufacture controlled, and Stackelberg game withnretailers controlled were constructed. Some results applied dynamic optimization theory made with Hamilton function. The conclusions are as follows. (1) Optimization brand investment controlled by manufacture has nothing to do with time. (2) Retail price was the most minimum when channel was integrated. (3) Manufacture’s profits of uncoordinated static game and Stackelberg game with manufacture controlled were more than Stackelberg game withnretailers controlled. (4) Retailer’s profits of Stackelberg game withnretailers controlled were less than Stackelberg game with manufacture controlled. (5) Channel’s total profits of Stackelberg game withnretailers controlled were the most minimum.

The development, survivorship, and reproduction of brown citrus aphid, Toxoptera citricida (Kirkaldy), were evaluated at 8 constant temperatures (8, 10, 15, 20, 25, 28, 30, and 32°C). The developmental periods of immature stages ranged from 63.1 d at 8°C to 5.5 d at 30°C. The lower developmental threshold for the brown citrus aphid immature was estimated at 6.27°C. The upper temperature threshold of 31.17°C for development of nymph was determined from a nonlinear biophysical model. The percentage of survivorship of immature stages varied from 81 to 97% within the temperature range of 8–30°C. However, survivorship was reduced to 29% at 32°C. The average longevity of adult females ranged from 60.0 d at 10°C to 6.5 d at 32°C. The average progeny per female was 52.5 at 20°C and 7.5 at 32°C. The largest rm (0.3765) occurred at 28°C. Populations reared at 10 and 32°C had the smallest rm values of 0.0588 and 0.0960, respectively. The mean generation time of the population ranged from 51 d at 10°C to 8 d at 32°C. The optimal range of temperature for T. citricida population growth was 20–30°C. Several mathematical functions were used to quantify brown citrus aphid development, survivorship, reproduction and lifetable parameters in relation to temperatures.

In a distribution channel, channel members are not always self-interested, but altruistic in some conditions. Based on this assumption, this paper adopts a behavior game method to analyze and forecast channel members’ decision behavior based on result fairness preference and reciprocal fairness preference by embedding a fair preference theory in channel research of coordination. The behavior game forecasts that a channel can achieve coordination if channel members consider behavior elements. Using the behavior game theory model we established, we can prove that if retailers only consider the result fairness preference and they are not jealous of manufacturers’ benefit, manufacturers will be more friendly to retailers. In such case, the total utility of the channel is higher compared with that of self-interest channel, and the utility of channel members is Pareto improved. If both manufactures and retailers consider reciprocal fairness preference, the manufacturers will give a lower wholesale price to the retailers. In return, the retailers will also reduce retail prices. Therefore, the total utility of the channels will not be less than the total utility of the channel coordination, as long as the reciprocity wholesale prices meet certain conditions.

An existence result for the solution set of symmetric vector quasi-equilibrium problems that allows for discontinuities is obtained. Moreover, sufficient conditions for the generalized Levitin-Polyak well-posedness of symmetric vector quasi-equilibrium problems are established.