Two novel ensemble approaches for improving classification of neural networks

x, 77 leaves ; 29 cmThe task of pattern recognition is one of the most recurrent tasks that we encounter in our lives. Therefore, there has been a significant interest of automating this task for many decades. Many techniques have been developed to this end, such as neural networks. Neural networks are excellent pattern classifiers with very robust means of learning and a relatively high classification power. Naturally, there has been an increasing interest in further improving neural networks’ classification for complex problems. Many methods have been proposed. In this thesis, we propose two novel ensemble approaches to further improving neural networks’ classification power, namely paralleling neural networks and chaining neural networks. The first seeks to improve a neural network’s classification by combining the outputs of a set of neural networks together via another neural network. The second improves a neural network’s accuracy by feeding the outputs of a neural network into another and continually doing so in a chaining fashion until the error is reduced sufficiently. The effectiveness of both approaches has been demonstrated through a series of experiments. i

Tensile Creep and Creep-Recovery Behavior of a SiC-Fiber Si 3 N 4 -Matrix Composite

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65802/1/j.1151-2916.1993.tb03753.x.pd

Inhibitive effect of sodium (E)-4-(4-nitrobenzylidenamino) benzoate on the corrosion of some metals in sodium chloride solution

The inhibition performance of a novel anionic carboxylic Schiff base, sodium (E)-4-(4-nitrobenzylideneamino)benzoate (SNBB), was investigated for various metals, namely low carbon steel F111, pure iron and copper, in neutral 10 mM NaCl solution. Potentiodynamic polarization, scanning vibrating electrode technique (SVET), quantum chemical (QC) calculation, and molecular dynamics (MD) simulation were employed. The potentiodynamic polarization data showed that SNBB acts as an effective corrosion inhibitor for both iron and F111 steel, but it is not effective for the copper. In situ spatially-resolved SVET maps evidenced a major change in surface reactivity for Fe and F111 steel immersed in 10 mM aqueous solution in the absence and in the presence of SNBB. Featureless ionic current density distributions were recorded in the presence of SNBB at both their spontaneous open circuit potential (OCP) and under mild anodic polarization conditions, while major ionic flows were monitored above the metals in the absence of SNBB. On the basis of computer simulations, it is proposed that SNBB produces a stable chelate film on iron and steel surfaces that accounts for the good corrosion inhibition efficiency observed. The different inhibition efficiencies of SNBB molecules on the iron and copper was attributed to the special chemical structure of SNBB molecule and its different chelation ability with the released metal ions on the metal surface. The QC calculations also confirmed the high corrosion inhibition efficiency of SNBB. The MD simulation indicated higher binding energy of SNBB on iron surface compared to that of copper surface. The interaction mode of SNBB on iron and F111 steel surfaces corresponds to a mixed chemical and physical adsorption, and it obeys the Langmuir isother

Experimental studies of particle-covered droplets in electric fields: Mechanical and rheological properties of droplets and interfacial particle organization

Wydział FizykiMoja rozprawa doktorska zawiera wyniki badań podstawowych w zakresie fizyki materii miękkiej i wnosi wkład w zrozumienie mechanicznych właściwości oraz kinetyki zachowania kropel pokrytych cząstkami stałymi. Do uzyskania takich kropel i badania ich mechanicznych i reologicznych właściwości wykorzystywałem pole elektryczne, które umożliwiło mi także obserwowanie różnych form organizacji cząstek na powierzchni międzyfazowej kropel. Mechanizm ich powstawania opierał się na zjawiskach elektrycznych, takich jak pływy elektrohydrodynamiczne, elektrokoalescencja, dielektroforeza czy elektroforeza. Większość moich badań dotyczyła pojedynczej kropli pokrytej cząstkami stałymi poddanej działaniu jednorodnego stałego bądź zmiennego pola elektrycznego, choć obserwowałem także zachowanie kropli w niejednorodnym polu elektrycznym. Wyniki moich badań dotyczą deformacji, relaksacji, elekrorotacji kropel, koalescencji oraz mechanizmu tworzenia się warstwy cząstek na powierzchni międzyfazowej. Wiedza zdobyta na podstawie doświadczeń przeprowadzanych na pojedynczych kroplach (podparta analizą teoretyczną) pozwala lepiej zrozumieć bardziej złożone układy, jak na przykład emulsje.This thesis contains fundamental experimental studies in soft matter physics, focusing on the understanding of mechanical properties and kinetics of particle-covered droplets. In my research, I utilized electric field methods for the formation of particle-laden droplets and investigation of their mechanical and rheological properties. I also used different electric field approaches to study organization of the particles adsorbed at the droplet interfaces. These electric phenomena include electrohydrodynamic circulation flows, electrocoalescence, and dielectrophoretic and electrophoretic interactions. My research concerns a single particle-covered droplet subjected to uniform DC and AC electric fields, though, I also investigated the behavior of droplets in a non-uniform field. The results included in this thesis cover studies on the droplet’s deformation and relaxation, electrorotation, and arrested coalescence, as well as the mechanics of a particle shell formed on the fluid–fluid interface. The knowledge gained from the experiments (supplemented by theoretical studies) on individual droplets will be useful in studying more complex systems, such as emulsions.I thank the Polish National Science Centre for financial support through the research project within the OPUS funding scheme (2015/19/B/ST3/03055: Mechanical properties, specific release and motility of patchy colloidosomes—an emerging class of structures), and PRELUDIUM funding scheme (2019/35/N/ST5/02821: Electric-field-induced deformation and crumpling of non-spherical particle shells formed on droplets)

Experimental studies of particle-covered droplets in electric fields: Mechanical and rheological properties of droplets and interfacial particle organization

Wydział FizykiMoja rozprawa doktorska zawiera wyniki badań podstawowych w zakresie fizyki materii miękkiej i wnosi wkład w zrozumienie mechanicznych właściwości oraz kinetyki zachowania kropel pokrytych cząstkami stałymi. Do uzyskania takich kropel i badania ich mechanicznych i reologicznych właściwości wykorzystywałem pole elektryczne, które umożliwiło mi także obserwowanie różnych form organizacji cząstek na powierzchni międzyfazowej kropel. Mechanizm ich powstawania opierał się na zjawiskach elektrycznych, takich jak pływy elektrohydrodynamiczne, elektrokoalescencja, dielektroforeza czy elektroforeza. Większość moich badań dotyczyła pojedynczej kropli pokrytej cząstkami stałymi poddanej działaniu jednorodnego stałego bądź zmiennego pola elektrycznego, choć obserwowałem także zachowanie kropli w niejednorodnym polu elektrycznym. Wyniki moich badań dotyczą deformacji, relaksacji, elekrorotacji kropel, koalescencji oraz mechanizmu tworzenia się warstwy cząstek na powierzchni międzyfazowej. Wiedza zdobyta na podstawie doświadczeń przeprowadzanych na pojedynczych kroplach (podparta analizą teoretyczną) pozwala lepiej zrozumieć bardziej złożone układy, jak na przykład emulsje.This thesis contains fundamental experimental studies in soft matter physics, focusing on the understanding of mechanical properties and kinetics of particle-covered droplets. In my research, I utilized electric field methods for the formation of particle-laden droplets and investigation of their mechanical and rheological properties. I also used different electric field approaches to study organization of the particles adsorbed at the droplet interfaces. These electric phenomena include electrohydrodynamic circulation flows, electrocoalescence, and dielectrophoretic and electrophoretic interactions. My research concerns a single particle-covered droplet subjected to uniform DC and AC electric fields, though, I also investigated the behavior of droplets in a non-uniform field. The results included in this thesis cover studies on the droplet’s deformation and relaxation, electrorotation, and arrested coalescence, as well as the mechanics of a particle shell formed on the fluid–fluid interface. The knowledge gained from the experiments (supplemented by theoretical studies) on individual droplets will be useful in studying more complex systems, such as emulsions.I thank the Polish National Science Centre for financial support through the research project within the OPUS funding scheme (2015/19/B/ST3/03055: Mechanical properties, specific release and motility of patchy colloidosomes—an emerging class of structures), and PRELUDIUM funding scheme (2019/35/N/ST5/02821: Electric-field-induced deformation and crumpling of non-spherical particle shells formed on droplets)

The Politics of Consumer Subsidy Reform in Jordan and Morocco

Why do some authoritarian regimes succeed in eliminating universal consumer subsidies while others fail? Specifically, facing similar fiscal challenges and a threat of social unrest, why did Jordan succeed in replacing its system of universal consumer subsidies with a means-tested cash transfer scheme while Morocco did not? This dissertation seeks to explain the divergent subsidy reform outcomes in Jordan and Morocco by examining several cases of subsidy reform in each country. I argue that subsidy reform is more likely to succeed when regimes introduce effective compensatory measures to members of their coalition while simultaneously demobilizing potential opposition to subsidy reform to prevent the emergence of broad-based mass mobilization. Crucially, the ability of authoritarian regimes to provide effective compensation is shaped by the composition of the coalition. When the regime’s core constituents are concentrated in the public sector and the military (as is the case in Jordan), exclusive compensatory measures are easier to implement through wage increases and extended benefits. Governments can blame private employers and businesses for not introducing similar wage increases. Conversely, when members of the regime coalition who benefit from consumer subsidies are dispersed over different sectors of the economy (as is the case in Morocco), the regime’s ability to devise and implement targeted compensation measures is limited. Any compensation measure is likely to be narrowly targeted, augmenting the cost of exclusion and increasing the risk of mass mobilization. In such a scenario, the continuation of subsidies is the politically optimal option. I develop my argument through an in-depth analysis of eleven episodes of subsidy reform in Jordan and Morocco between 1974 and 2018. I utilize a variety of sources including elite interviews and archival material collected over three months of field research in Jordan and Morocco. The argument has two main implications. First, it suggests that greater attention to the coalitional dynamics within authoritarian regimes can enhance our understanding of social policy in nondemocratic settings. Second, it invites greater skepticism of the effectiveness of the IMF/World Bank subsidy reform template

A Report on Propagative Influence: An Influence measure for directed and undirected networks

In this report, we present a new influence measure, namely Propagative Influence - PI. PI measure defines influence of a node in terms of its relationships. It suggests that a node's influence is a product of the interactions of nodes and is a state given to the node by the recognition and endorsements of others. We show that using PI will identify all influential nodes in a network in an effective and timely manner. The theory of this measure is very relevant and easily understood. We propose two variations of this measure, Static Propagative Influence - SPI and Dynamic Propagative Influence - DPI. Both variations use the same underlying algorithm but differ in influence propagation values. In this work, the abilities and effectiveness of our proposed measure is demonstrated through a series of examples on synthetic datasets which reflect real-world situations