Parametric Analysis of Particle Spreading with Discrete Element Method

The spreading of metallic powder on the printing platform is vital in most additive manufacturing methods, including direct laser sintering. Several processing parameters such as particle size, inter-particle friction, blade speed, and blade gap size affect the spreading process and, therefore, the final product quality. The objective of this study is to parametrically analyze the particle flow behavior and the effect of the aforementioned parameters on the spreading process using the discrete element method (DEM). To effectively address the vast parameter space within computational constraints, novel parameter sweep algorithms based on low discrepancy sequence (LDS) are utilized in conjunction with parallel computing. Based on the parametric analysis, optimal material properties and machine setup are proposed for a higher quality spreading. Modeling suggests that lower friction, smaller particle size, lower blade speed, and a gap of two times the particle diameter result in a higher quality spreading process. In addition, a twoparameter Weibull distribution is adopted to investigate the influence of particle size distribution. The result suggests that smaller particles with a narrower distribution produce a higher-quality flow, with a proper selection of gap. Finally, parallel computing, in conjunction with the LDS parameter sweep algorithm, effectively shrinks the parameter space and improves the overall computational efficiency

Asset Pricing and Cost of Equity for US Banking Sector by CAPM and TFPM from 1987-2011

Although Capital Asset Pricing Model (CAPM), one-factor model, has strong theoretical basis and is easy to use and understand, analysts also consider other alternative models, such as Three Factor Pricing Model (TFPM) developed by Fama and French (1993). Because some differences between actual return and estimated return could be explained by the effect of capital size and book-to-market ratio. The objective of using these two similar but complementary models is to estimate the cost of equity for the US banking sector. In order to do the estimation, we would conduct the estimation of parameters for both individual bank and the whole banking sector

dd-wave Charge-4e4e Superconductivity From Fluctuating Pair Density Waves

In this work we show that in several microscopic models for the pair-density-wave (PDW) state, when the PDW wave vectors connect special parts of the Fermi surface, the predominant instability driven by PDW fluctuations is toward a pairing state of the PDW boson themselves{, realizing a long-saught-after charge-$4e$ superconductor. Dual to the scenario for electron pairing, the effective attraction between the bosons is mediated by exchanging low-energy fermions.} In particular we show that the pairing interaction for the charge-$4e$ order is repulsive in the $s$-wave channel but attractive in the $d$-wave one. By analyzing the Ginzburg-Landau free energy including the fluctuation effects of PDW, within a large-$M$ extension of the theory, we find that the charge-$4e$ superconductivity emerges as a vestigial order of PDW, and sets in via a first-order transition.Comment: 12 pages with 4 figure

Empresariado étnico en Valencia relacionado con el sector construcción: análisis cualitativo del caso chino

[ES] En los últimos años se ha constatado un aumento considerable en el número de negocios gestionados por empresarios chinos en Valencia y una diversificación de su tipología. Cafeterías, bares, bazares, zapaterías y tiendas de ropa se han sumado a los tradicionales restaurantes chinos. También se ha observado que cuando estos negocios emprenden reformas suelen recurrir a constructores también chinos. El propósito de este estudio es describir al empresariado étnico de origen chino dedicado a la construcción y a actividades inmobiliarias en Valencia. Para ello se realiza una investigación cualitativa a través de entrevistas a dos tipologías de participantes: 1) propietarios de negocios chinos vinculados a la construcción y al sector inmobiliario, 2) clientes de dichos negocios. Sub-objetivos: Profundizar en la historia y el pasado del empresariado étnico de origen chino en Valencia Conocer las razones por las que el empresariado chino del sector servicios contratan a constructoras e inmobiliarias chinas como primera opción. Describir las actividades de las empresas chinas relacionadas con el sector de la construcción.Wu, Y. (2019). Empresariado étnico en Valencia relacionado con el sector construcción: análisis cualitativo del caso chino. http://hdl.handle.net/10251/118518TFG

Analýza a srovnání sezónních trendů na akciových trzích ve zvolených regionech

With the development of behavioral finance, scholars around the world have begun to study stock markets in an attempt to find specific patterns that exist. The Efficient Market Hypothesis (EMH) has a very important place in modern financial market investment theory. It was proposed in Fama (1970), while it assumes that the relevant information already available in the securities market is fully utilized and is fully and correctly reflected in the price of securities. However, a large body of empirical research has shown that there are anomalies in the stock markets, the occurrence of extraordinary returns on certain assets or portfolios of assets, which cannot be explained by the efficient market hypothesis. One of the important anomalies in the stock markets is the calendar effect, which refers to the phenomenon of extraordinary returns that can be achieved by trading at a particular time in the stock markets. There are many types of calendar effects, including day-of-the-week, month-of-the-year, holiday, and seasonal effects. These anomalies may not be always disadvantageous for investors, and it may even be possible that investors who follow these effects may earn some unusual income. The aim of this thesis is to find out whether there are significant differences in calendar effect within different geographical regions. Five stock indices, each representing one geographical area were selected to achieve the aim. Using the research methodology of a GARCH model, a computational analysis is carried out to determine when the weekly and monthly effects of each of the five selected stock markets are present.With the development of behavioral finance, scholars around the world have begun to study stock markets in an attempt to find specific patterns that exist. The Efficient Market Hypothesis (EMH) has a very important place in modern financial market investment theory. It was proposed in Fama (1970), while it assumes that the relevant information already available in the securities market is fully utilized and is fully and correctly reflected in the price of securities. However, a large body of empirical research has shown that there are anomalies in the stock markets, the occurrence of extraordinary returns on certain assets or portfolios of assets, which cannot be explained by the efficient market hypothesis. One of the important anomalies in the stock markets is the calendar effect, which refers to the phenomenon of extraordinary returns that can be achieved by trading at a particular time in the stock markets. There are many types of calendar effects, including day-of-the-week, month-of-the-year, holiday, and seasonal effects. These anomalies may not be always disadvantageous for investors, and it may even be possible that investors who follow these effects may earn some unusual income. The aim of this thesis is to find out whether there are significant differences in calendar effect within different geographical regions. Five stock indices, each representing one geographical area were selected to achieve the aim. Using the research methodology of a GARCH model, a computational analysis is carried out to determine when the weekly and monthly effects of each of the five selected stock markets are present.154 - Katedra financívelmi dobř

Srovnání běžných účtů v Číně s ohledem na FinTech

With the rapid development of financial technology, the banking system has changed with the development of financial technology. More and more Chinese people begin to use e-banking for online transactions. Even small shops on Chinese streets are paying with QR codes. Fewer and fewer people use cash to trade. The aim of this thesis is to introduce the relationship between the development of financial science and technology in China and banks, and to compare and analyze the current accounts of banks in China. This thesis is divided into five chapters. The first chapter is a brief introduction. The second chapter is the description of China's banking system and China's FinTech development characteristics. The third chapter introduces the analysis method of Multi-Criteria Decision-Making. The fourth chapter is based on Multi-Criteria Decision-Making analysis of the current account of ten banks in China. The last chapter is the conclusion of this thesis.With the rapid development of financial technology, the banking system has changed with the development of financial technology. More and more Chinese people begin to use e-banking for online transactions. Even small shops on Chinese streets are paying with QR codes. Fewer and fewer people use cash to trade. The aim of this thesis is to introduce the relationship between the development of financial science and technology in China and banks, and to compare and analyze the current accounts of banks in China. This thesis is divided into five chapters. The first chapter is a brief introduction. The second chapter is the description of China's banking system and China's FinTech development characteristics. The third chapter introduces the analysis method of Multi-Criteria Decision-Making. The fourth chapter is based on Multi-Criteria Decision-Making analysis of the current account of ten banks in China. The last chapter is the conclusion of this thesis.154 - Katedra financívelmi dobř

Motif-Centric Representation Learning for Symbolic Music

Music motif, as a conceptual building block of composition, is crucial for music structure analysis and automatic composition. While human listeners can identify motifs easily, existing computational models fall short in representing motifs and their developments. The reason is that the nature of motifs is implicit, and the diversity of motif variations extends beyond simple repetitions and modulations. In this study, we aim to learn the implicit relationship between motifs and their variations via representation learning, using the Siamese network architecture and a pretraining and fine-tuning pipeline. A regularization-based method, VICReg, is adopted for pretraining, while contrastive learning is used for fine-tuning. Experimental results on a retrieval-based task show that these two methods complement each other, yielding an improvement of 12.6% in the area under the precision-recall curve. Lastly, we visualize the acquired motif representations, offering an intuitive comprehension of the overall structure of a music piece. As far as we know, this work marks a noteworthy step forward in computational modeling of music motifs. We believe that this work lays the foundations for future applications of motifs in automatic music composition and music information retrieval