Hydrophobic interaction plays an important role in biology, daily lives, and a variety of industrial processes such as flotation. While the mechanisms of hydrophobic interactions at molecular scale, as in self-assembly and micellization, is relatively well understood, the mechanisms of macroscopic hydrophobic interactions have been controversial. It is, therefore, the objective of the present work to study the mechanisms of interactions between macroscopic hydrophobic surfaces in H-bonding liquids, including water, ethanol, and water-ethanol mixtures. The first part of the present study involves the measurement of the hydrophobic forces in the thin liquid films (TLFs) confined between two identical hydrophobic surfaces of contact angle 95.3o using an atomic force microscope (AFM). The measurements are conducted in pure water, pure ethanol, and ethanol-water mixtures of varying mole fractions. The results show that strong attractive forces, not considered in the classical DLVO theory, are present in the colloid films formed with all of the H-bonding liquids tested. When an H-bonding liquid is confined between two hydrophobic surfaces, the vicinal liquid molecules form clusters in the TLFs and give rise to an attractive force. The cluster formation is a way to minimize free energy for the molecules denied of H-bonding with the substrates. Thus, solvophobic forces are the result of the antipathy between the CH2- and CH3-coated surface and H-bonding liquid confined in the film. A thermodynamic analysis of the solvophobic forces measured at different temperatures support this mechanism, in which solvophobic interactions entail decreases in the excess film enthalpy and entropy. The former represents the energy gained by building clusters, while the latter represents loss of entropy due to structure building. Thus, hydrophobic interaction may be a subset of solvophobic interaction. The solvophobic forces are strongest in pure water and pure ethanol, and decrease when one is added to the other. Adding a very small amount of ethanol to water sharply reduced the solvophobic force due to the adsorption of the former with an inverse orientation. An exposure of the OH-group toward the aqueous phase decreases the antipathy between the surface and H-bonding liquid and hence causes the hydrophobic (or solvophobic) forces to decrease. The second part of the study involves the measurement of the hydrophobic forces in the wetting films of water using the force apparatus for deformable surfaces (FADS). This new instrument recently developed at Virginia Tech is designed to monitor the deformation of bubbles to determine the surface forces in wetting films. In effect, an air bubble is used a force sensor. The measurements have been conducted with gold, chalcopyrite, and galena as substrates. The results obtained with all three minerals show that hydrophobic force increases with increasing water contact angle, suggesting that hydrophobic forces are inherent properties of hydrophobic surfaces rather than created from artifacts such as preexisting nanobubbles and/or cavitation. A utility of the intrinsic relationship between hydrophobic force and contact angle is to predict flotation kinetics from the hydrophobicity of the minerals of interest. / Ph. D.

By increasing fruit exposure to sunlight and influencing fruit development, leaf thinning in the fruit zone can improve grape quality and lower disease incidence; however, further investigations on the timing, varietal response and intensity are needed to optimize results and to better understand underlying physiologic responses. Fruit zone leaf thinning was applied at different timing and intensities to evaluate its effect on cluster health and fruit composition in Cabernet Sauvignon and Chardonnay. Treatments consisted of control (C), pre-bloom leaf thinning (PB) and two levels of fruit-set leaf thinning (three leaves, PF3 and six leaves, PF6). In an additional project on Cabernet Sauvignon, two levels of hedging (17th node, NH and 12th node, H) were integrated with no leaf thinning (L) and fruit set leaf thinning (LR, three leaves). All leaf thinning treatments consistently reduced disease incidence compared to control vines in both varieties, with the reduction extent varying between 2017 and 2018. Yield was not negatively affected by leaf thinning treatments, even though PB reduced cluster compactness by decreasing the number of berries per cluster of Chardonnay in 2017. Control vines tended to have greater titratable acidity than defoliated vines, while Brix and pH responses varied between seasons. No direct positive correlation was found between sunlight exposure and norisoprenoids concentration. Post fruit set leaf thinning PF6 consistently increase free norisoprenoids at harvest, while pre-bloom defoliation never did. Heterogeneous responses were observed for bound and total norisoprenoids. In Cabernet Sauvignon free, bound and total 1,1,6-trimethyl-1,2-dihydronaphtalene (TDN) was consistently increased by PF3. Hedging negatively influenced Brix and anthocyanins accumulation in 2017, and increased free norisoprenoids while decreasing the bound and total fraction. Results revealed that a high level of stress possiblt caused by excess sunlight and/or reduced photosynthesis might negatively affect norisoprenoids glycosylation. / Master of Science in Life Science / This project evaluates the effect of a grapevine canopy management practice on grape quality. The objective was to find a suitable technique to expose the fruits to sunlight in order to increase grape aroma concentration and improve grape sanitary status of Virginia vineyards. Leaves were removed from the fruit zone with different intensities at two grape developmental stages, in two varieties (Chardonnay and Cabernet Sauvignon). Treatments consisted of control, three leaves removed before blooming (PB) and three or six leaves removed after fruit set (PF3 and PF6 respectively) In an additional project with Cabernet Sauvignon, the effect of canopy height was integrated with the fruit zone defoliation. Results showed that the removal of leaves from the fruit zone is effective in improving grape sanitary status at harvest, with the improvement extent depending on the season climatic conditions and on the amount of leaves removed. Crop yield was not negatively affected by treatments. Non defoliated grapes tended to have greater acidity at harvest, while sugar responses were inconsistent. Aroma compounds responded heterogeneously to fruit zone defoliation, but volatile odorants were consistently greatest in the most exposed grapes (PF6) compared to all other treatments at harvest. Pre-bloom defoliation instead, never increased volatile aroma compounds compared to control at harvest. Generally, non-volatile odorants were greater in less severely defoliated vines or control. An overall positive effect was observed with PF3. Canopy height was demonstrated to be able to indirectly affect grape quality and composition, with the short canopy reducing grape’s sugar and color content and increasing grape’s volatile aroma compounds concentration at harvest in 2017. The removal of three or six leaves from the fruit zone in post fruit set could be a suitable practice to improve grape quality in the Virginia environment.

Quantification of grape glycosides has been suggested as an objective index of grape quality. Two studies were undertaken to observe the influence of vineyard management on grape glycosides. In the first study, three crop levels from mature Cabernet Sauvignon (<i>Vitis vinifera</i> L.) vines grown in eastern Virginia were evaluated for their influence on grape glycosides, expressed as red-free glycosyl glucose (GG). Crop levels averaged 3.2, 5.1, and 6.4 kg/vine resulting in leaf area to fruit weight ratios (cm²/g) of 34.4, 27.0 and 19.2, respectively. Red-free GG was greatest in juice from fruit of the low treatment at four of seven sampling dates, including harvest. Phenolic glycosides were found to comprise as much as half of the total GG value. In a second study, shoot thinning, mechanical and hand fruit zone leaf removal of mature Cabernet Sauvignon grapevines were evaluated for their influence on red-free GG. Two shoot densities were examined, each with no leaf removal (No LR), mechanical leaf removal (M LR) or mechanical plus hand leaf removal (M+H LR) imposed five weeks post-bloom. Red-free GG was increased by leaf removal of shoot thinned vines and was greatest with mechanical plus hand leaf removal. / Master of Science

This research examined the physical and economic feasibility of using 35mm aerial photos to space access corridors for thinning two overstocked loblolly pine plantations in the piedmont of Virginia. Tree diameters at groundline were predicted as functions of photo-measured crown areas. The capacity of the accumulator on the feller-buncher, an assumed operating swath, and the photo determined diameters enabled the estimation of distances that the machine could travel while thinning before accumulating a full load. Productivities and costs of felling, bunching, and skidding per cord of wood were evaluated with computer simulations for three thinning procedures. The costs of planning the thinning by ground methods and photos were compared so that the least cost planning and harvesting system could be determined. Results showed that row thinning had the lowest simulated harvesting costs with no planning expenses. In the access corridor procedures, the photo planning with newly acquired photos and harvesting in the photo corridor spacing system were more expensive than ground marking and harvesting in corridors 70 feet apart. Photo corridor spacings enabled the feller-buncher to attain higher productivities in the selective thinnings between corridors. Indications were that corridor spacing is stand specific. / M.S.

Reservoir computers rely on an internal network to predict the future state(s) of dynamical processes. To understand how a reservoir's accuracy depends on this network, we study how varying the networ's topology and scaling affects the reservoir's ability to predict the chaotic dynamics on the Lorenz attractor. We define a metric for diversity, the property describing the variety of the responses of the nodes that make up reservoir's internal network. We use Bayesian hyperparameter optimization to find optimal hyperparameters and explore the relationships between diversity, accuracy of model predictions, and model hyperparameters. The content regarding the VPT metric, the effects of network thinning on reservoir computing, and the results from grid search experiments mentioned in this thesis has been done previously. The results regarding the diversity metric, kernel tests, and results from BHO are new and use this previous work as a comparison to the quality and usefulness of these new methods in creating accurate reservoir computers.

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第21835号 / 農博第2348号 / 新制||農||1068(附属図書館) / 学位論文||H31||N5207(農学部図書室) / 京都大学大学院農学研究科農学専攻 / (主査)教授 白岩 立彦, 教授 稲村 達也, 准教授 田中 朋之 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

Although there remains some controversy as to the benefits of individual tree growth and yield prediction models over stand-level models, individual tree models still have wide acceptance. A generalized thinning response variable which can account for the intensity of thinning, as well as the age of the stand at the time of thinning and the time elapsed since thinning, was applied to two existing models for loblolly pine (Pinus taeda) in cutover site-prepared plantations. A site index equation for predicting mean total height of dominant and co-dominant trees and a diameter increment model were developed to incorporate the thinning response variable. New fits of height increment and mortality functions to the available data were also completed. Separate mortality functions were fit to data from unthinned and thinned stands. The base models for this analysis were from the individual tree growth simulation model PTAEDA2. Evaluations for predictive ability of these models were done in a reduced version of the growth simulator which was modified to accept external data. The mean total height model had improved predictive ability over the original PTAEDA2 model for this variable. The diameter increment model produced no significant improvement in simulation comparisons. Fitting the two mortality functions to the multiple observation data resulted in the reduced predictive ability of the simulator compared to the original mortality model from PTAEDA2 which was fit to data from unthinned stands only. / Master of Science

Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-05-03T14:57:17Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) petronio_henrique_alves.pdf: 952268 bytes, checksum: c672a103f4c27e5369547a6558985c5d (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-05-17T12:03:12Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) petronio_henrique_alves.pdf: 952268 bytes, checksum: c672a103f4c27e5369547a6558985c5d (MD5) / Made available in DSpace on 2017-05-17T12:03:12Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) petronio_henrique_alves.pdf: 952268 bytes, checksum: c672a103f4c27e5369547a6558985c5d (MD5) Previous issue date: 2016 / Os objetivos deste trabalho foram avaliar a influ?ncia do desbaste e da fertiliza??o p?s-desbaste no crescimento de ?rvores de um povoamento clonal de eucalipto e comparar a idade t?cnica de desbaste (ITD), obtida atrav?s do M?todo dos Ingressos Percentuais, com a idade t?cnica de corte (ITC) de dois povoamentos de clones de eucalipto. Para o primeiro objetivo, os dados foram coletados em 30 parcelas permanentes, sendo 16 convencionais e 14 g?meas, em que foi analisado o efeito do desbaste (parcela convencional) e da fertiliza??o (parcela g?mea) sobre o crescimento das ?rvores. O desbaste foi realizado aos 81 meses, com intensidade de 20%, 35% e 50% de ?rea basal presente, eliminando os piores indiv?duos, e a fertiliza??o aplicada aos 99 meses. As vari?veis analisadas resultantes da totaliza??o dos dados das parcelas foram ?rea basal (B), di?metro m?dio (q), altura total m?dia (Ht) e volume total com casca (Vcc). A an?lise dos dados constituiu-se na compara??o do efeito de vari?veis em rela??o ? idade por meio de modelo de regress?o, e foi realizada aos 99 meses ap?s o desbaste e aos 81 meses ap?s a fertiliza??o. Para atender ao segundo objetivo, os dados foram coletados em 34 parcelas permanentes, instaladas em povoamentos com espa?amento de 3,0 x 2,5 metros, em dois s?tios diferentes. Essas parcelas foram medidas aos 24, 36, 48, 60 e 72 meses, durante o Invent?rio Florestal Continuo (IFC). O M?todo dos Ingressos Percentuais foi empregado para determinar a ?poca de realiza??o do primeiro desbaste. Para projetar as distribui??es diam?tricas, para idades superiores ? ?ltima medi??o, utilizou-se um modelo de distribui??o diam?trica, que consiste na recupera??o dos par?metros de uma fun??o de densidade de probabilidade (f.d.p) ao longo dos anos. Neste trabalho, adotou-se a fun??o Weibull, que foi ajustada pelo m?todo de m?xima verossimilhan?a. A partir das informa??es de n?mero de indiv?duos e valores estimados para os par?metros da fun??o Weibull, ? e ?, de ambas as distribui??es diam?tricas analisadas, calculou-se o ingresso percentual (IP) de ?rvores em classes de di?metro sucessivas ao longo do tempo. Para determinar a ITD, foi ajustado um modelo exponencial justaposto a um modelo linear simples. A ITC foi definida como o momento em que o incremento corrente ? igual ao incremento m?dio, sendo a produtividade volum?trica, ao longo do tempo, estimada pelo modelo de Clutter. O desbaste apresentou influ?ncia para as vari?veis ?rea basal, volume total com casca e di?metro m?dio, por?m n?o influenciou a altura total m?dia. A fertiliza??o realizada ap?s o desbaste n?o influenciou a produ??o das vari?veis analisadas. A idade t?cnica de desbaste de um povoamento de eucalipto localizado em um s?tio de maior capacidade produtiva ocorre antes, comparado com a idade de desbaste de um povoamento em um local de produtividade inferior. Esse mesmo comportamento ocorre para a idade t?cnica de corte. Para um mesmo s?tio, a idade t?cnica de desbaste ocorre ap?s a idade t?cnica de corte. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / The objectives of this work were to evaluate the influence of thinning and post-thinning fertilization on tree growth of a clonal eucalypt stand, and compare the thinning technical age (ITD), obtained by the Percentages Ingress Method, with the harvest technical age (ITC) of two clonal eucalypt stands. For the first objective, the data were collected in 30 permanent plots, 16 conventional and 14 twins, in which were analyzed the effect of thinning (conventional plot) and fertilization (twin plot) on tree growth. The thinning was carried out at 81 months, with intensity of 20%, 35% and 50% of present basal area, eliminating the worst individuals, and the fertilization applied at 99 months. The analyzed variables resulting from the summation of data from plots were basal area (B), quadratic diameter (q), mean total height (Ht) and total volume with bark (Vcc). The data analysis consisted in the comparison of variable effects, in relation to age, through regression model, and was held at 99 months after the thinning and 81 months after fertilization. To attend the second objective, the data were collected in 34 permanent plots, installed in stands with spacing of 3.0 x 2.5 meters, in two different sites. These plots were measured at 24, 36, 48, 60 and 72 months, during the Continuous Forest Inventory (IFC). The Percentages Ingress Method was employed to determine the epoch of realization of the first thinning. To project the diameter distributions for older ages after the last measurement, there was used a diameter distribution model, which consists in recovering the parameters of a probability density function (f.d.p) along the years. In this work, it was adopted the Weibull function, which was adjusted by the maximum likelihood method. From the information of number of individuals and estimated values for the parameters of the Weibull function, ? and ?, from both analyzed diameter distributions, it was calculated the percentage ingress (IP) of trees in successive diameter classes along the time. To determine the ITD it was adjusted an exponential model juxtaposed to a simple linear model. The ITC was defined as the moment that the current increment is equal to the average increment, in which the volumetric productivity along the time was estimated by Clutter model. The thinning presented influence for the variables basal area, total volume with bark and quadratic diameter, however did not affect the mean total height. The fertilization performed after thinning did not influence the production of the analyzed variables. The thinning technical age of an eucalypt stand located in a higher productive capacity site occurs earlier compared to the thinning age of a stand in a lower productivity site. This same behavior occurs for the harvest technical age. For the same site, the thinning technical age occurs after the harvest technical age.

Das Formdrücken findet seine industrielle Anwendung in der Herstellung rotationssymmetrischer Hohlbauteile für kleine und mittlere Losgrößen. Diese Bauteile werden häufig in einem weiteren Verfahrensschritt als Vorform für die Herstellung profilierter Hohlkörper genutzt. Verfahrensbedingt tritt bereits bei der Vorformherstellung eine ungewollte Blechdickenabnahme auf. Um diese Blechdickenabnahme zu minimieren, wurde anhand numerischer Methoden das Verfahren des Rotationsschwenkbiegens an der Professur Virtuelle Fertigungstechnik der TU Chemnitz entwickelt. Das Prinzip dieses inkrementellen Umformprozesses basiert auf einer Verfahrenskombination des konventionellen Drückens und des Schwenkbiegens, mit dem Ziel der faltenfreien Herstellung von Hohlbauteilen bei gleichzeitiger minimaler Blechausdünnung. Die als Halbzeug verwendete Ronde wird zu Beginn des Prozesses auf eine formgebende Matrize gespannt und in Rotation versetzt. Durch die Schwenkbewegung eines zylindrischen Umformwerkzeuges wird das ebene Blech an die Kontur der Matrize angelegt, wobei keine Relativbewegung zwischen Blech und Werkzeug stattfindet. Demzufolge entstehen minimale Zugspannungen in der Blechebene und die Blechausdünnung wird deutlich verringert. Durch die Durchmesserreduzierung bilden sich jedoch ebenso tangentiale Druckspannungen aus, welche zu einer ungewollten Faltenbildung führen können. Im Rahmen des Vortrages werden anhand von FEM-Simulationen Möglichkeiten vorgestellt, um diese Druckspannungen zu reduzieren oder gezielt zur Vorformherstellung für profilierte Hohlbauteile zu nutzen.

This work aims to study the procedures of fingerprint identification system and to present some efficient algorithms for pre-processing and minutiae extraction. Most pre-processing steps consist of normalization, segmentation and orientation estimation, and background which focus on decreasing the variance of fingerprints, separating fore and background areas and tracking the direction of ridge lines, respectively. Minutiae extractionis typically divided into two approaches: binarization based method and directgray scale extraction. However, we put emphasis on binarization based method in thisresearch since it is more commonly used method in research papers. The results of simulationbased on a set of fingerprints downloaded from FVC 2006 database showed thatalgorithms we used are accurate and reliable.