443 research outputs found
Aperçus sur la législation civile
No full textWang Shengming. Aperçus sur la législation civile. In: Revue internationale de droit comparé. Vol. 46 N°1, Janvier-mars 1994. pp. 7-9
Wang Shuo and the commercialisation of contemporary Chinese culture
No full textThis thesis examines the commercialisation of Chinese culture that has taken place over the past twenty years in mainland China. It explores the contribution of Wang Shuo, a cultural figure who straddles different fields of culture, moving from literature to the ultimate mass culture medium of television, this study plots Wang Shuo' s development from educational failure, to business failure, to fiction writer, film & TV editor, film director and cultural critic and analyst. His stories, films, TV series and articles have caused shock-waves throughout national cultural circles as he has transformed the terms of the debate from academic discourse to a validation of the role of the market in the culture field. Although Wang Shuo has not been labelled as a dissident, his approach to the culture market has had a more subversive effect on official ideology that those overt dissidents who have had to live in exile or have been imprisoned. He has utilised the language of official ideology to satirise the authorities, turning the ideology and its supporters into figures of fun. Yet his own goals have been strictly personal and economic ones. The authorities recognize the value of Wang Shuo's work in the cultural market but at the same time distrust his works and place him under strict censorship. Examining the way Wang Shuo and people surround him have succeeded in different fields of cultural achievement is a mirror to understanding the process of the transformation of contemporary Chinese culture from a socialist state-controlled culture to a market-oriented mass culture industry
Low threshold ErxYb(Y)(2-x)SiO5 nanowire waveguide amplifier
No full textThe 1.53 mu m gain characteristics of ErxYb(Y)(2-x)SiO5 nanowire and film material waveguide amplifiers have been investigated considering the upconversion effect by solving rate equations and propagation equations. The gains of ErxYb(Y)(2-x)SiO5 nanowire waveguides have a significant enhancement compared with those of film material waveguides due to low propagation loss and long photoluminescence lifetime. The cooperative upconversion (CUC) effect plays a significant role in the simulation. The maximum 27 dB/mm gain for a 1 mm length ErxYb(Y)(2)-xSiO(5) nanowire waveguide was obtained without CUC, and only about 2 dB/mm gain was obtained with CUC. However, the low thresholds of 10.7 and 0.7 mW, respectively, for the ErxY2-xSiO5 and ErxYb2-xSiO5 nanowire waveguides amplifiers were observed with CUC by analyzing the relation between optical gain and the Er/Yb/Y concentration, waveguide length, waveguide cross section area, energy-level lifetime, and pumping power coefficients. The low threshold is two to three orders of magnitude lower than the threshold used in thin film experiments. (c) 2015 Optical Society of AmericaOpticsSCI(E)[email protected]
From data to dynamism: the role of data and learning models in startup potential analysis
No full textIn the contemporary era, the landscape of innovation and entrepreneurship is dynamically evolving, fueled by a substantial surge in venture capital investments and the rapid expansion of the global startup ecosystem. This burgeoning growth not only highlights the vibrant nature of modern economies but also brings to the forefront the critical importance of identifying startups with high potential for success. As venture capital firms and investors seek to maximize their returns on investment, the ability to accurately assess and predict the future performance of these nascent companies becomes paramount. This dissertation delves into the heart of this challenge, aiming to refine and enhance the methodologies used in evaluating startup potential, thereby contributing valuable insights and tools to both academic scholars and industry practitioners.
Existing methods for assessing startup potential have predominantly relied on static variables such as financial performance indicators, market size estimates, and competitive positioning. While these factors offer valuable insights, they fall short in capturing the dynamic and often unpredictable nature of startup growth and success. This raises several pertinent questions: How can we move beyond these traditional metrics to more accurately predict startup success? Furthermore, is it possible to develop more advanced tools that not only provide predictions but also facilitate a more interactive, dynamic evaluation process? These questions highlight the limitations of current approaches and pave the way for the innovative research presented in this dissertation, which seeks to explore these opportunities through the application of advanced data analytics and learning models.
The dissertation is structured around three main chapters, each contributing to the overarching aim of developing a comprehensive framework for startup evaluation. The first chapter emphasizes the importance of mapping the interactions between various entities within the startup ecosystem, including companies, venture capital firms, and individuals. This interaction-centric view provides a foundational understanding of the complex interdependencies that influence startup success.
Building on this foundation, the second chapter introduces an expanded interaction network and integrates company demographic features to improve the identification of high-potential startups. Additionally, this chapter explores the entrepreneurial homophily principle, which posits that startups with similar characteristics tend to cluster together, further supporting the theoretical underpinnings of the proposed methodologies.
The third chapter represents a pioneering effort to leverage large language models (LLMs) for building an interactive, domain-centric tool aiming at dynamically evaluating startup potential. This novel application of LLMs opens up exciting possibilities for creating an interactive agent that can continuously update its assessments based on evolving data, offering a more fluid and responsive tool for venture capital decision-making.
In summary, this dissertation marks a significant advancement in the field of startup evaluation by utilizing a diverse array of entrepreneurial data, combined with cutting-edge learning models. The research not only advances our theoretical understanding of startup dynamics but also offers practical tools for identifying startups with the highest potential for success. Through its comprehensive analysis and innovative methodologies, this work stands as a seminal contribution to the ongoing efforts to enhance the precision and relevance of startup potential assessment.Ph.D.Includes bibliographical reference
Fabrication and characterization of transparent ceramics for solid state laser applications
No full textTransparent ceramics have been known to be one of the best materials for solid state lasers application. Known for its flexibility to be doped with different elements with excellent transmittance, it has been used widely as a host for solid state lasers.
This work consists of the fabrication of Holmium-doped Yttria (Ho:Y2O3) transparent ceramics via co-precipitation process followed by vacuum sintering to produce the final transparent ceramic samples. The samples are then polished and characterized using tools like Scanning Electron Microscope and UV-vis Spectroscopy. Parameters that were investigated include the heating rate of during vacuum sintering and alternative routes for rapid rate sintering method. Based on the microstructure of the samples, we determined the porosity, relative density as well as the in-line optical transmittance of the samples, which are factors considered when producing a high quality transparent ceramic product.
It was found out that a higher heating rate will yield differences in densification between the near center and near surface regions of the sample, resulting in inhomogeneous densification. This results in pores trapped in the center of the sample due to the formation of a hard shell near the surface of the samples, which ultimately inhibit the full densification of the samples and hence a lower optical transmittance value. A two-step rapid rate sintering was used and investigated and proved to yield decent results.Bachelor of Engineering (Materials Engineering
Internal Migration and Income Inequality in China: Evidence from Village Panel Data
No full textExisting studies on the impact of migration on income inequality at sending communities suffer from severe methodology defects and data limitations. This paper analyzes the impact of rural-to-urban migration on inequality using a newly constructed panel dataset for around 100 villages over a ten-year period from 1997 to 2006 in China. To our best knowledge, this is the first paper that examines the dynamic aspects of migration and income inequality employing a dynamic panel data analysis. Unlike earlier studies focusing exclusively on remittances, our data include the total labor earnings of migrants in destination areas. Furthermore, we look at the gender dimension of the impact of migration on wage inequality within the sending communities. Since income inequality is time-persisting, we use a system GMM framework to control for the lagged income inequality in estimating the effect of emigration on income inequality in the sending villages. At the same time, contemporary emigration is validly instrumented in the GMM framework because of the unobserved time-varying community shock that correlates with emigration and income inequality, as well as with the potential reverse causality from income inequality to emigration. We found a Kuznets (inverse U-shaped) pattern between migration and income inequality in the sending communities. Specifically, contemporary emigration increases income inequality, while lagged emigration has strong income inequality-reducing effect in the sending villages. A 50-percent increase in the lagged emigration rate translates into one-sixth to one-seventh standard deviation reduction in inequality. Contemporary emigration has slightly smaller effects in raising the income inequality within villages. These effects are robust to the different specifications and different measures of inequality. More interestingly, the estimated relationship between emigration and the gender wage gap also has an inverse U-shaped pattern. Emigration tends to increase the gender wage gap initially, and then tends to decrease it in the sending villages.Internal Migration; Inequality; System GMM.
Inequality and Internal Migration in China: Evidence from Village Panel Data
No full textThis paper analyzes the impact of rural-to-urban migration on income inequality and gender wage gap in source regions using a newly constructed panel dataset for around 100 villages over a ten-year period from 1997 to 2006 in China. Since income inequality is time-persisting, we use a system GMM framework to control for the lagged income inequality, in which contemporary emigration is also validly instrumented. We found a Kuznets (inverse U-shaped) pattern between migration and income inequality in the sending communities. Specifically, contemporary emigration increases income inequality, while lagged emigration has strong income inequalityreducing effect in the sending villages. A 50-percent increase in the lagged emigration rate translates into one-sixth to one-seventh standard deviation reduction in inequality. These effects are robust to the different specifications and different measures of inequality. More interestingly, the estimated relationship between emigration and the gender wage gap also has an inverse Ushaped pattern. Emigration tends to increase the gender wage gap initially, and then tends to decrease it in the sending villages.Internal Migration; Inequality; System GMM
A Numerical Investigation of an Abnormal Phenomenon of Stress Intensity Factor (SIF) in a Cracked T-Butt Joint Accounting for Welding Effect
No full textIndustry design standards such as BS 7910 deployed some empirical formulas for the prediction of stress intensity factor (SIF) based on simulation results from traditional finite element method (FEM). However, such FEM simulation occasionally failed to convince people due to the large discrepancies compared with engineering practice. As a consequence, inaccuracy predictions via such formulas in engineering standards inevitably occur, which will compromise the safety of structures. In our previous research work, an abnormal phenomenon of SIF in a cracked T-butt joint accounting for welding effect has been observed. Compared with BS 7910, the calculation results of SIF at the surface points of welded specimens cannot be well predicted, with a large discrepancy appearing. In order to explore such problem with an abnormal increase at the surface points of cracked welded specimens, a numerical investigation in terms of SIF among BS 7910, XFEM, and FEM is performed in this paper. Numerical models on both a simple cracked plate without welding effect and a cracked T-butt joint with welding effect are developed through ABAQUS. Parametric studies in terms of the effects of varied crack depth to thickness ratio (a/T) and the effects of crack depth to crack half-length ratio (a/c) are carried out. Empirical solutions from BS 7910 are used for comparison. It is found that the XFEM can provide predictions of SIF at both the crack deepest point and crack surface point of a simple cracked plate as accurate as FEM. For a T-butt joint with a transverse stiffener, a large discrepancy in terms of the weld magnification factors (Mk) occurs at the crack surface point compared with empirical predictions. An exceptional increase of von Mises stress gradient in regions close to the weld-toe is found through the simulation of FEM, whereas a constant stress gradient is obtained through XFEM. The comparison results indicate an inappropriate prediction of SIF by the utilization of the empirical formulas in BS 7910. A more reasonable prediction of the SIF at the surface point of a crack is obtained by the XFEM. Therefore, further updating of the empirical solutions in BS 7910 for SIF accounting for welding effect is recommended.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Transport Engineering and Logistic
Numerical Simulation of Fatigue Crack Growth in a Stiffened Plate
No full textFatigue is the most common source behind failures of mechanical structures. In order to study the phenomena, experiments have been performed by Lloyd's Register and other tests have been presented in literature. Performing real life fatigue experiments requires a long time, a considerable amount of money and it is size limited. The solution is to create and validate numerical models which are accurate and reliable.This is the main reason why the research is focusing on the prediction of the crack growth, using numerical models. The reference geometry for this study is a plate with longitudinal stiffener, since a lack of knowledge about this shape has been noticed in literature.In order to better understand the current knowledge in the topic of fracture mechanics, an extensive literature review has been performed. Considering a plate with longitudinal or transverse stiffener, the crack always appears at the weld toe, and propagates with a charactheristic semi-elliptical shape. The empirical solutions needed to compute crack propagation are presented in the British Standard 7910 (BS7910), but additional correction factors have been described in literature Anderson, 2005, Bowness and Lee, 2000, Han et al, 2014 and Newman and Raju, 1981.An additional research has been performed about the 3D modeling using the finite element method. The standard FEM can be used to compute the Stress Intensity Factor (SIF) along with a dedicated "spider web" mesh around the crack front. A valid alternative is marked by the newly introduced XFEM method, which uses an element definition with additional terms; these terms are able to consider the crack discontinuity and the stress singularity at the crack tip.The empirical equations and the correction factors have been merged in 14 sets of equations. The objective of this first study is to assess the conservativeness of the solution proposed in the BS7910. A MATLAB empirical model has been created with the equations and the Paris law crack growth. The results of these models are compared to tests from literature and to the experiments from LR. An high accuracy is achieved using the set of equations from the BS7910 and using the correct load ratio.The FEM model has been created to define a new XFEM meshing technique able to supply accurate SIF results; finally, as demonstration of the accuracy of the XFEM models, the empirical equations has been compared with the 3D finite element models.An extensive mesh convergence study was performed, reaching a good agreement for the crack in a simple plate, both using the standard FEM method and the newly introduced XFEM solution. Finally, a comparison between the new XFEM mesh and the standard mesh in a plate with transverse stiffener was performed. This latest comparison highlighted a big discrepancy in the SIF solution for the surface point of the semi-elliptical crack. This difference was demonstrated to be the consequence of an erroneous stress distribution in the standard FEM model.The research has brought to the conclusion that the empirical model using the BS7910 is able to deliver accurate results, if the correct load ratio is considered. While in the FEM model analysis, it has been demonstrated that the empirical equation from Bowness and Lee, 2000 is not accurate at predicting the stress intensity factor at the surface point. This finding was revealed thanks to the use of the XFEM finite element method along with a detailed meshing technique
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