Theoretical and Experimental Research on CO2 Electrical Heating Pool Boiling Heat Transfer Outside a Horizontal Tube

Numerical simulation on electrical heating pool boiling heat transfer with CO2 as refrigerant outside a horizontal tube is carried. A voltage-controlled heating method has been used in the experiment, with the advantages of good stability and adjustability of the experimental heat flux density. After a series of preliminary calculation and pre-work, numerical simulation is carried based on a software FLUENT. Bubble behaviors are observed, the distribution regularity of volume fraction of vapor is obtained and compared with the experimental results. The results show that numerical simulation and experimental results are in good agreement. Furthermore, by changing the heat flux density, the comparison of velocity on center location of experimental tube is analyzed. Varying pattern is satisfying. Evidently, for velocity, the simulation values are relatively higher and the data locate in the range of 1.40~1.52 times higher than the experimental data. This paper makes useful exploration of CO2 pool boiling heat transfer and the design of evaporator

Joint Motion Deblurring and Superresolution from Single Blurry Image

Currently superresolution from a motion blurred image still remains a challenging task. The conventional approach, which preprocesses the blurry low resolution (LR) image with a deblurring algorithm and employs a superresolution algorithm, has the following limitation. The high frequency texture of the image is unavoidably lost in the deblurring process and this loss restricts the performance of the subsequent superresolution process. This paper presents a novel technique that performs motion deblurring and superresolution jointly from one single blurry image. The basic idea is to regularize the ill-posed reconstruction problem using an edge-preserving gradient prior and a sparse kernel prior. This method derives from an inverse problem approach under an efficient optimization scheme that alternates between blur kernel estimation and superresolving until convergence. Furthermore, this paper proposes a simple and efficient refinement formulation to remove artifacts and render better deblurred high resolution (HR) images. The improvements brought by the proposed combined framework are demonstrated by the processing results of both simulated and real-life images. Quantitative and qualitative results on challenging examples show that the proposed method outperforms the existing state-of-the-art methods and effectively eliminates motion blur and artifacts in the superresolved image

A User-Centered Concept Mining System for Query and Document Understanding at Tencent

Concepts embody the knowledge of the world and facilitate the cognitive processes of human beings. Mining concepts from web documents and constructing the corresponding taxonomy are core research problems in text understanding and support many downstream tasks such as query analysis, knowledge base construction, recommendation, and search. However, we argue that most prior studies extract formal and overly general concepts from Wikipedia or static web pages, which are not representing the user perspective. In this paper, we describe our experience of implementing and deploying ConcepT in Tencent QQ Browser. It discovers user-centered concepts at the right granularity conforming to user interests, by mining a large amount of user queries and interactive search click logs. The extracted concepts have the proper granularity, are consistent with user language styles and are dynamically updated. We further present our techniques to tag documents with user-centered concepts and to construct a topic-concept-instance taxonomy, which has helped to improve search as well as news feeds recommendation in Tencent QQ Browser. We performed extensive offline evaluation to demonstrate that our approach could extract concepts of higher quality compared to several other existing methods. Our system has been deployed in Tencent QQ Browser. Results from online A/B testing involving a large number of real users suggest that the Impression Efficiency of feeds users increased by 6.01% after incorporating the user-centered concepts into the recommendation framework of Tencent QQ Browser.Comment: Accepted by KDD 201

A KINEMATIC ANALYSIS OF ROUND KICK IN TAEKWONDO

The purpose of this study is to provide kinematic analysis of the round kick in Taekwondo. The round kick is an important component required in the performance of Taekwondo. In order to accomplish this skill, it is necessary to accelerate the movement of the leg to a high velocity. In order to determine the mechanism involved in this maneuver, kinematic analysis of the motion will be used. This study analyzed the round kick motion through application of the 3D-video analysis system. The data determined that the muscles of the thigh initiate the round kick, transmitting force from the hip, through to the shank and finally to the foot. Before kicking the target, the knee-joint flexes to increase the velocity of leg and then the lower limbs extend. These are the requirements for a rapid and powerful kick

Factors Affecting Trust in Chinese Digital Journalism: Approach Based on Folk Theories

Trust in online digital news has become a significant concern affecting social cohesion in China. Under the framework of folk theories, we interviewed urban and rural residents' perceptions and imaginations of digital news credibility in China's digital journalism environment. The study finds that digital media giants in China are utilised by both urban and rural residents. Regarding the behaviour of news avoidance, scepticism of digital news accounts for only a tiny fraction of the reasons held by news avoiders. Chinese urban and rural residents have similar perceptions about the impact of news forms, quality of information, and individual stances on digital news, while rural residents show uncertainty about the transparency of news production, which may be related to their education level and media literacy. The relationship between recommendation algorithms and news trust is overlooked by respondents. In addition, news seekers are more likely to display herd behaviours, which may mislead their judgment of news credibility. News avoiders may refuse to consume news because of their distaste for China's digital news atmosphere, such as the ubiquity of unpleasant emotions, preconceived opinions, and attention-grabbing clickbait headlines

Study on the Inhibitory Effects of Ephedra Aconite Asarum

Dendritic cells (DCs) can secrete cytokines stimulated by lipopolysaccharide (LPS), which leads to not just acute inflammatory responses but also Th1 polarization. Furtherly, chronic inflammation or autoimmune diseases could be triggered. As a classic Traditional Chinese Medicine formula, Ephedra Aconite Asarum Decoction with the main ingredients of ephedrine and hypaconitine can show effect on anti-inflammation and immunoregulation. But it remains unclear whether Ephedra Aconite Asarum Decoction controls DCs. In this study, we investigated the effects of Ephedra Aconite Asarum Decoction on LPS-induced bone marrow-derived DCs (BMDCs) in vitro. We found that Ephedra Aconite Asarum Decoction lowered surface costimulators on DCs and reduced the expression of Th1 type cytokines. Yet it is slightly beneficial for shifting to Th2. Our work reveals that the Ephedra Aconite Asarum Decoction can regulate Th1 inflammation through intervening DCs

Experimental study on concrete damage location by Computerized tomography technology

In order to solve the technical problem of damage localization in the concrete damage process, the Computerized Tomography (CT) scanning damage localization test was carried out under uniaxial compression. In addition to the three-dimensional meso model, the porosity variation law of concrete pore or cracks at different loading stages are obtained. A damage variable is created based on CT images. The results show that the change of porosity, pore volume and damage variable is consistent with the loading process. The rapid increase of concrete pore volume and damage variable can be the precursor of concrete damage. The whole process of the development and evolution of concrete cracks was observed and analyzed comprehensively by using the three-dimensional reconstruction images. A method for prognosist the evolution and localization of cracks in concrete by comprehensively analyze the CT reconstruction images, rapid increase of concrete pore volume and rapid growth of damage variable is presented

Experimental study on concrete damage location by Computerized tomography and Acoustic Emission technology

In order to solve the technical problem of damage localization in the concrete damage process, the Computerized Tomography (CT) scanning test and Acoustic Emission (AE) damage localization test was carried out under uniaxial compression. In addition to the three-dimensional meso model, the porosity variation law of concrete pore or cracks at different loading stages are obtained. A damage variable is created based on CT images and AE damage points. A damage variable based on CT image and AE damage point is established. The results show that the change of porosity, pore volume and damage variable is consistent with the loading process. The rapid increase of concrete pore volume and damage variable can be the precursor of concrete damage. The whole process of the development and evolution of concrete cracks was observed and analyzed comprehensively by using the three-dimensional reconstruction images and acoustic emission damage location map. A new method for analyzing the evolution and localization of cracks in concrete is presented. &nbsp

Combating Disinformation or Reinforcing Cognitive Bias: Effect of Weibo Poster’s Location Disclosure

This study conducted a controlled experiment to examine the impact of posters’ IP disclosure on the perceptions of Weibo users with different habits and information preferences and explore whether such disclosure facilitates the fight against disinformation or deepens cognitive biases. Results showed that the IP location of the information poster does influence users’ judgments of the authenticity of the information and that the consistency between users’ long-term residence and poster IP is not important for users to make judgments about the credibility of information. The high level of usage of Weibo also has no effect on users’ judgment of the credibility of the information, and this may be related to the small difference in college students’ overall use of Weibo. The results also showed that users’ perceptions of information’s accuracy, logical coherence, absence of bias, alignment with their own views, consistency with the majority opinion, and trustworthiness of its source are all statistically positively correlated with the overall credibility of information