Dissertations / Theses: 'Through-holes'

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DUFOUR, Tabatha. "Black holes as standard candles through their Hawking radiations." Thesis, Stockholms universitet, Fysikum, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-194014.

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As they are evaporating, black holes are emitting radiations called Hawking radiations. Our goal is to determine at which distance it is possible to measure those radiations with current telescopes. Being capable of measuring those radiations would mean that we can use them as standard candles i.e. we could use it as distance indicator. To do so, we are first going to compute the different characteristics of a black hole such as its energy peak, temperature, flux and lifetime. Knowing that, we will be able to describe how, theoretically, we could use black holes as standard candles. Finally, we will take the Fermi-LAT telescope as an example of what we can observe in practice and at which distance.

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Yi, Jue-Min. "Diffraction of single holes through planar and nanostructured metal films." Phd thesis, Université de Strasbourg, 2013. http://tel.archives-ouvertes.fr/tel-01018454.

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The theme of my thesis is to investigate the diffraction behavior of subwavelength holes in metal films, and to understand the surface plasmons' (SPs) role in aperture far-field diffraction. We have built a home-made goniometer setup with high-level quality. A series of single hole continuously ranging from k*r>>1 to k*r<

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Suckling, James Rowland. "Transmission of microwaves through subwavelength slits and holes in metal." Thesis, University of Exeter, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426088.

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Green, Gaberella [Verfasser]. "Women Who Knocked Holes Through The Glass Ceiling: A Phenomenological Study / Gaberella Green." Munich : GRIN Verlag, 2015. http://d-nb.info/1097438597/34.

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Ponti, Gabriele <1977&gt. "Probing the innermost regions around supermassive black holes through X–ray spectral variability." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/364/.

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Osho, A. (Aquila). "Identifying opportunities in an unstructured and emerging network through the visualizations of structural holes." Master's thesis, University of Oulu, 2014. http://urn.fi/URN:NBN:fi:oulu-201405211431.

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In order to succeed in a mega project, SMEs are requested to need networks that entails diversity of relationships. This research aims to investigate the emerging network of SMEs active in the Nuclear Power plant project to be built in the town of Pyhäjoki, and likewise similar competences that could lead to possible collaboration within the network. This study aims at contributing both managerially and theoretically. From a managerial viewpoint, it is highly essential for strategists, SME managers, and business-to-business marketers to be extremely conscious of their surrounding environment in order to make comprehensive decisions. Acquiring a comprehensive knowledge of the surrounding network is highly essential for companies competing in Nuclear Power Plant markets where much-hyped overactive competition has become a reality. Theoretically, going through earlier collaboration and strategic alliance network studies gave an opportunity to properly approach examining and identifying how network visualization of structural holes can be used to explore opportunities for collaboration within emerging networks. This study is considered a descriptive research. 154 companies are represented in the online portal (lisaakauppaa.fi), 49 of them would be analyzed, and they were singled out according to their competencies and their labor force. Structural hole was applied on the network of possible collaboration in order to reveal the entrepreneurial opportunities surrounding it. The outcome of the research exhibits prominent actors alongside with opportunities confronting them in the networks.

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Lee, Yonghee. "Heat transfer enhancement for turbulent flow through blockages with elongated holes in a rectangular channel." Texas A&M University, 2003. http://hdl.handle.net/1969.1/5860.

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In this thesis, turbulent forced convective heat transfer downstream of blockages with elongated holes in a rectangular channel was studied. The rectangular channel has a width-to-height ratio of 12:1. The blockages have the same cross section as that of the channel. The diameter of all elongated holes of the blockages is three quarters of the channel height. The blockages are classified into two different types with two different hole-to-blockage area ratios (ratio of total crosssectional area of holes to cross-sectional surface area of the blockage) of 0.5 or 0.6. For each hole-to-blockage area ratio, the blockages are again subdivided into three different cases using three different aspect ratios (hole-width-to-height ratio) which are determined by the number of holes four, six, and eight holes per blockage. Experiments for total six different cases of blockages were performed under a uniform wall temperature condition (50C). The experiments were conducted at three different Reynolds numbers of about 7,000, 12,000, and 17,000, respectively. Three copper plate heaters with twenty one embedded thermocouples were used to measure the average heat transfer on the surface of channel walls between two consecutive blockages. Results from this study showed that the blockages with elongated holes enhance the average heat transfer by up to 5.06 and 4.08 times that by fully developed turbulent flow through a smooth channel at the same Reynolds numbers for small and large holeto- blockage area ratios, respectively. The friction factor ratios for small and large holeto- blockage area ratios of the blockages reached 345 and 89 times, respectively, that by fully developed turbulent flow through a smooth channel at the same Reynolds numbers. TP (Thermal Performance) values varied from 0.65 to 1.11 depending on cases. According to the results, Case L-2, which has six elongated holes and hole-toblockage area ratio of 0.6, is the best option from the TP point of view. But Case S-2, which also had six elongated holes and hole-to-blockage area ratio of 0.5, can be an alternative when more weight should be put on the heat transfer enhancement than TP value.

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Kummer, Joseph W. "Signal processing methods to quantify scattering of angle-beam shear waves from through-holes in plates." Thesis, Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54411.

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The objective of this thesis is to present analysis techniques that quantify the scattering of angle-beam ultrasonic waves from through-holes in plates. This topic is of interest because increased understanding of the scattering of ultrasonic waves by a defect is important for the development of many nondestructive evaluation (NDE) applications. Angle-beam techniques are commonly used in industry to detect and characterize defects, and many structures of concern have plate-like components. Scattering from through-holes is particularly important because cracks tend to form around fastener holes, which have high stress concentrations. In addition, varying boundary conditions within a fastener hole can change over the course of a structure’s lifetime and may have significant effects on NDE results. In this research, two signal processing techniques are developed to obtain scattering information from through-holes for a variety of fill conditions, including epoxy and complete and partial filling with metal inserts, using experimentally acquired wavefield measurements. Experimental procedures for acquiring wavefields, which measure the out of plane motion of ultrasonic waves on the surface of a specimen and allow for the visualization and characterization of propagating waves, are presented. Methods for obtaining radial and directional energy maps, which quantify scattering as a function of scattered angle and phase velocity, are described. In addition, baseline subtraction is used to obtain scattering patterns for both methods, which quantify scattering as a function of polar angle for each wave mode present in the wavefield. These techniques are applied to wavefield measurements from through-holes with various fill conditions to investigate the effects of boundary conditions on ultrasonic scattering. A comparison of the radial and directional energy mapping techniques, discussing the strengths and weaknesses of each approach, is provided, and recommendations are made for future work.

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Schumann, Wiebke. "Ätzung und Charakterisierung von Strukturen mit hohem Aspektverhältnis in Silizium am Beispiel von Through-Wafer-Via-Holes." Ilmenau Universitätsbibliothek Ilmenau, 2010. http://d-nb.info/1000955222/34.

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Miller, Douglas Dwight. "Stress intensity factors for circumferential part-through cracks from holes in hollow cylinders subjected to tension and bending loads." Thesis, Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/16055.

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Fu, Chia-Yu. "Application of internal state variable models to thermal processing and reliability of plated through holes in printed wiring boards." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/17375.

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Shepherd, Jason F. "Interval Matching and Control for Hexahedral Mesh Generation of Swept Volumes." BYU ScholarsArchive, 1999. https://scholarsarchive.byu.edu/etd/3452.

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Surface meshing algorithms require certain relationships among the number of intervals on the curves that bound the surface. Assigning the number of intervals to all of the curves in the model such that all relationships are satisfied is called interval assignment. Volume meshing algorithms also require certain relationships among the numbers of intervals on each of the curves on the volume. These relationships are not always captured by surface meshing requirements. This thesis presents a news technique for automatically identifying volume constraints. In this technique, volume constraints are grouped with surface constraints and are solved simultaneously. A sweepable volume has source, target and linking surfaces. The technique described in this thesis uses graph algorithms to identify independent, parallel sets of linking surfaces, and determine if they correspond to through-holes or blind-holes. For blind-holes, the algorithm generates constraints that prevent the hole from being too deep in interval parameter space and, thus, penetrating opposite target surfaces. For each linking set, the adjoining source and target surfaces are partially ordered by the structure of the linking set. A small set of representative paths for each linking set is found, and the representative paths for all linking sets are gathered and distilled by Gaussian elimination into a small set of constraints.

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Fuller, Matthew. "Transformer les capacités d'innovation : l'impact et l'influence des Fab Labs d'entreprise au sein de grands groupes Resetting innovation capabilities: the emergence of corporate fab labs Making nothing or something: corporate Fab Labs seen through their objects as they cross organizational boundarie Fitting squares into round holes: Enabling innovation, creativity, and entrepreneurship through corporate Fab Labs." Thesis, Paris Sciences et Lettres (ComUE), 2019. http://www.theses.fr/2019PSLED045.

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Inspirés par un modèle établi par une initiative sociale du Massachusetts Institute of Technology (MIT) en 2001, des salariés de plusieurs grandes groupes ont établi des Fab Labs d'entreprise avec l'intention de transformer les capacités d'innovation de leur entreprise.Cette thèse examine l'univers des Fab Labs entreprise, s'appuyant sur des données empiriques récoltées dans des dizaines de labs, avec des activités de recherche principales ayant lieu entre 2014 et 2017 dans les laboratoires de quatre grands groupes mondiaux. L'objectif de cette recherche est de 1) identifier si les Fab Labs d'entreprise influencent les capacités d'innovation d'une organisation, 2) articuler et affiner la représentation managériale utilisée pour justifier la création d'un tel lieu, ainsi que 3) esquisser un mécanisme simple qui permet aux décideurs stratégiques d'évaluer si les activités dans un lab lui permet d'atteindre ses objectifs
Based on a pattern established by an MIT academic outreach program created in 2001, individuals in dozens of large organizations established corporate Fab Labs in recent years with the intent to transform their firm’s ability to innovate.This thesis investigates the world of corporate Fab Labs, building on empirical data gathered from dozens of labs, with core research activities taking place in the labs of four large multinational firms from 2014 through 2017. The purpose of this research is to 1) identify whether corporate Fab Labs influence an organization’s innovation capabilities, 2) articulate and refine the managerial representation used to support the creation of these labs, and 3) outline a simple mechanism for managers to evaluate whether a lab attains its desired outcomes

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Hou, Bo. "Enhanced transmissions of classical waves through subwavelength apertures /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?PHYS%202007%20HOU.

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Wright, Diana Beth 1963. "Electromagnetic coupling by a wire through a cavity-backed circular aperture in an infinite screen." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276823.

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The problem of a wire penetrating a circular aperture in an infinite screen and coupling energy into a cavity behind that screen is considered. We formulate an integral equation in terms of the electric field in the aperture. This integral equation is solved using two approximate methods: a zeroth-order approximation valid at low frequencies, and the method of moments. In addition, we introduce an equivalent circuit model to aid in our physical interpretation of the problem. Numerical results for the interior current on the wire and for the equivalent circuit admittance parameters are presented in order to provide a comparison between the two approximations. Inside the cavity, we examine the components of the electric field as a function of position. Finally, the exterior magnetic field far from the aperture is studied as a function of frequency. We examine the relationship between interior resonance features associated with the presence of the cavity and observations of the exterior field.

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Martineau, Killian. "Quelques aspects de cosmologie et de physique des trous noirs en gravitation quantique à boucles Detailed investigation of the duration of inflation in loop quantum cosmology for a Bianchi I universe with different inflaton potentials and initial conditions Some clarifications on the duration of inflation in loop quantum cosmology A first step towards the inflationary trans-Planckian problem treatment in loop quantum cosmology Scalar spectra of primordial perturbations in loop quantum cosmology Phenomenology of quantum reduced loop gravity in the isotropic cosmological sector Primordial Power Spectra from an Emergent Universe: Basic Results and Clarifications Fast radio bursts and the stochastic lifetime of black holes in quantum gravity Quantum fields in the background spacetime of a polymeric loop black hole Quasinormal modes of black holes in a toy-model for cumulative quantum gravity Seeing through the cosmological bounce: Footprints of the contracting phase and luminosity distance in bouncing models Dark matter as Planck relics without too exotic hypotheses A Status Report on the Phenomenology of Black Holes in Loop Quantum Gravity: Evaporation, Tunneling to White Holes, Dark Matter and Gravitational Waves." Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAY044.

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Cantonnée à la physique mathématique depuis des décennies, la gravitation quantique entre désormais dans le giron de la science expérimentale. Suivant cette mouvance nous considérons dans cette thèse trois cadres d’application de la gravitation quantique à boucles (LQG) : le système Univers, les trous noirs et les astroparticules. Le troisième n’est qu’esquissé tandis que les deux premiers sont présentés plus en détails.Le secteur cosmologique étant l’un des domaines les plus prometteurs pour tester et contraindre des théories de gravité quantique, le développement de différents modèles tentant d’appliquer les idées de la LQG à l’Univers primordial ne s’est pas fait attendre. Les travaux que nous présentons portent sur la phénoménologie associée à ces modèles; tant dans le secteur homogène (où nous nous focalisons notamment sur la durée de la phase d’inflation), que dans le secteur inhomogène (nous étudions ce coup-ci le devenir des spectres de puissance primordiaux). Ces études combinées nous permettent alors de préciser dans quelle mesure des effets de gravité quantique (à boucles) peuvent être observés dans les anisotropies du fond diffus cosmologique.D’autre part les trous noirs, non contents de faire partie des objets les plus étranges et les plus fascinants de l’Univers, constituent également des sondes privilégiées pour tester des théories de gravitation. Nous développons la phénoménologie associée à différents traitements des trous noirs en gravitation quantique à boucles. Celle-ci intervient sur une grande variété de fronts : de l’évaporation de Hawking aux ondes gravitationnelles, en passant par la matière noire. C’est sans nul doute un domaine riche et vaste.Finalement, l’existence d’une échelle de longueur minimale, prédite par la majorité des théories de gravité quantique, suggère une généralisation du principe d’incertitude de Heisenberg. Partant de ce constat nous présentons également dans ce manuscrit une méthodologie permettant de calculer une nouvelle relation de dispersion de la lumière à partir du principe d’incertitude généralisé le plus couramment répandu
After decades of being confined to mathematical physics, quantum gravity now enters the field of experimental science. Following this trend, we consider throughout this thesis three implementation frameworks of Loop Quantum Gravity (LQG): the Universe as a system, black holes and astroparticles. The last one is only outlined while the first two are presented in more detail.Since the cosmological sector is one of the most promising areas for testing and constraining quantum gravity theories, it was not long before the development of different models attempting to apply the ideas of the LQG to the primordial Universe. The work we present deals with the phenomenology associated with these models; both in the homogeneous sector (where we focus particularly on the duration of the inflation phase), as in the inhomogeneous sector (where this time, we study the fate of the primordial power spectra). These combined studies then allow us to specify to what extent effects of (loop) quantum gravity can be observed in the anisotropies of the cosmic microwave background.On the other hand black holes, not content to be among the strangest and most fascinating objects of the Universe, are also prominent probes to test the theories of gravitation. We develop the phenomenology associated with different treatments of black holes in the loop quantum gravity framework, which intervenes on multiple levels: from the evaporation of Hawking to gravitational waves, including dark matter. This is undoubtedly a rich and vast area.Finally, the existence of a minimal length scale, predicted by the majority of quantum gravity theories, suggests a generalization of the Heisenberg uncertainty principle. On the basis of this observation, we also present in this manuscript a methodology to derive a new relation dispersion of light from the most widely used generalized uncertainty principle

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Sethapati, Vivek Venkata. "Computational Fluid Flow Analysis of the Enhanced-Once through Steam generator Auxiliary feedwater system." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/77020.

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The once through steam generator (OTSG) is a single pass counter flow heat exchanger in which primary pressurized water from the core is circulated. Main Feedwater is injected in an annular gap on the outer periphery of the steam generator shroud such that it aspirates steam to preheat the feedwater to saturation temperature. An important component of the OTSG and enhanced once through steam generator (EOTSG) is the auxiliary feedwater system (AFW), which is used during accident/transient scenarios to remove residual heat by injecting water through jets along the outer periphery of the heat exchanger core directly on to the tubes at the top of the OTSG. The intention is for the injected water, which is subcooled, to spread into the tube nest and wet as many tubes as possible. In this project, the main objectives were to use first principles Computational Fluid Dynamics to predict the number of wetted tubes versus flow rate in the EOTSG at the AFW injection location above the top tube support plate. To perform the fluid analysis, the losses in the bypass leakage flow and broached hole leakage flow were first quantified and then used to model a 1/8th sector of the EOTSG. Using user defined functions (UDF), the loss coefficients of the leakage flows were implemented on the 1/8th sector of the EOTSG computational model to provide boundary conditions at the bypass flow and leakage flow locations With this method, the number of tubes wetted in the sector of EOTSG for various AFW flow rates was found. Results showed that the number of wetted tubes was in very close agreement to that predicted by experimental-analytical methods by the sponsor, AREVA. With the maximum flow rate of 65 l/s a total of 318 tubes were wetted and the percentage of tubes wetted with broached holes was 8.7%. The analysis on the bypass leakage flow showed that the loss coefficients was a function of the mass flow rate or the flow Reynolds number through the gap and it increased as the Reynolds number increased from 300 to 1600. The experimental and computational loss coefficients agree to within 15% of each other. In contrast, the constant loss coefficient of 1.3 used by AREVA was much higher than that obtained in this study, particularly in the low Reynolds number range. As the Reynolds number approached 3000, the loss coefficients from this study approached the value of 1.3. This value of the loss coefficient was implemented for the bypass flow leakage in the 1/8th sector of the EOTSG model. The analysis on the broached hole leakage flow was performed using a single hole, five holes, and one, two, four and eight rows of broached holes in order to characterize the loss coefficients. The one hole and five hole computational models were validated with experiments. The computational models showed the presence of voids in the leakage flow through the tube support plate (TSP), which were not observed (visually) in the experiments. The characterization of the broached hole leakage in the one, two and four rows showed that the loss coefficient of the control broached hole increased as the number of rows increased. These results indicated that for the same height of water on the TSP, the resistance to leakage flow increased as the number of tubes increased. They also indicated that leakage flow through the broached holes was not solely a function of the height of water above the TSP but also the surrounding geometrical topology and the flow characteristics. However, the analysis done for eight rows showed that the loss coefficient became constant after a certain number of rows as the loss coefficient differed by only 5% from the results of the four rows. From these results it was determined that the loss coefficient asymptotes to an estimated value of 4.0 which was implemented in the broached hole leakage flow in the 1/8th sector of the EOTSG. Computational models of the 1/8th sector of the EOTSG were implemented with the respective loss coefficients for the bypass and leakage flows. Results showed that as the AFW flow rate increased, the percentage wetted tubes increased. The data matched closely with AREVA's experimental-analytical model for flow rates of 14.5 l/s and higher. It was also deduced that complete wetting of the tubes is not possible at the maximum AFW flow rate of 65 l/s.
Master of Science

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Lin, Po-shen, and 林柏伸. "Pulse Reverse Copper Plating in Through-Holes." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/39123776798483369938.

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碩士
逢甲大學
化學工程學所
94
Industry at present adopt direct current join additive in the trough liquid to electroplate. This experiment studies the purpose in order to electroplate in the through-hole with all kinds of wave forms and electroplate in having additive and additive-free trough liquid.Expectation can with change of wave form, is it replace electricity produce process additive used to come. Though the additive can be improved the result electroplated, but after using some time, may pollute the trough liquid. And lead to the fact the trough liquid needs reconfiguring, cause the improvement of the cost. The result of this experiment shows, Throwing Power that direct current electroplate really enough well, rough to can only up to 30-60%. But if cooperate with the additive, can still improve it and Throwing Power to 60-85%.By Pulse Reverse electroplate and can improve the Throwing Power of plating layer of through-hole to 70% in additive-free cases with the pulse, even reach 95% High Throwing Power. Although Pulse Reverse electroplate can improve the Throwing Power. But because show in the experimental result picture the structure of plating layer is comparatively levelled in order to there are additive experiments. So must cooperate with additive can is it plate layer even to let just still.

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Cameron, Craig D. "An exploration of international development through sport : happiness and holes /." 2005.

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Wang, David, and 王大瑋. "Investigation of optical transmission properties through tapered holes array slab." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/68152682587440939583.

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碩士
國立彰化師範大學
物理學系
98
The objective of this thesis is to investigate the optical transmission characteristics in two dimensional silicon nitride (SiN) photonic crystal slabs (PCSs), having holes array with straight and tapered sidewall, respectively. Two topics in optical characteristics are discussed: guided resonances in bare hole-PCSs and surface plasmon resonances in the metallic thin film coated hole-PCSs. The processes were started from using a freestanding SiN membrane, made by photolithography in combination with KOH wet etching, to be a substrate. The two dimensional holes array was transferred onto the SiN membrane by using a standard electron beam lithography, in which the straight and tapered sidewall holes array were achieved by using reactive ion etcher and followed by ion milling etcher. The optical transmission intensity was obtained by measuring the transmission signal with a normal incident light through the sample with wavelength ranging from 400 to 900 nm. For the sample with hole diameter of 300 nm, the transmittance spectrum measured on the tapered sidewall holes array revels blue shift with respect to that of the straight sidewall holes array. The similar tendency is also observed on the sample with hole diameter of 200 nm. A numerical calculation based on the finite element method was carried out. The simulation results are in a good agreement with the experimental ones. In addition, the transmission signals of tapered sidewall holes array are stronger than that of straight sidewall holes array when they were both coated with a 30 nm-thick gold film. These stronger transmission signals were attributed to surface plasmon resonances.

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Chen, Yi-Cheng, and 陳易呈. "An Investigation of Micro Molding for Micro Through Holes Plates." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/52156717125549652416.

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碩士
國立雲林科技大學
機械工程系碩士班
91
In this study, UV-LIGA technique was developed to fabricate the micro mold for inkjet print nozzle plates. Such micro molding process to manufacture nozzle plates is expected to substitute the existing laser machining method because of lower cost of molding machines. Number of innovative idea are implemented into mold design, manufacture and molding process. Micro core pins were made by the UV-LIGA process and were used as electrodes to create micro holes in the following EDM process. Since micro holes were made by the micro core pins, it ensured the alignment accuracy between the two mold halves. The micro-through holes to be duplicated were 100μm in diameter. The thickness of the plates was 50μm. Because of its extremely small thickness, high-speed injection molding has to be applied to fill the material within a very short period. Unfortunately, short shot still occurred while applied 300mm/s of injection speed, and 100℃ of mold temperature. In order to overcome this problem, vario-thermal control system is introduced in this work. This allows the mold temperature to be higher than its glass transition temperature during filling, and then to be cooled down by circulating cooling oil after filling. Finally, the micro nozzle plates was successfully molded while applied mold temperature of 150℃ and injection speed of 200mm/s. Such technology can be applied to some other products such as micro filters, bio-chips and IC test fixtures which has micro through holes. Keywords:UV-LIGA, Micro nozzle plate, EDM, Rapid response vario-thermal control system

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Lo, Jia-You, and 羅嘉佑. "Silicon wafer through-holes fabricated by photo-assisted electrochemical etching." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/gxf929.

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碩士
國立臺灣師範大學
機電科技研究所
96
This research developed photo-assisted electrochemical etching (PAECE) system with low-cost light source for fabricating high-density silicon wafer through-holes array. This process is described as followed: high-density through-holes array in silicon is etched by photo-assisted electrochemical etching under various parameters, such as illumination, surfactants, and concentrations, then to improve the through-hole etching fabrication to obtain through-holes array with high etching rate and smooth etching sidewall. The developed technology will be promising for applications of integrated probe array and wafer-level package in the further. Its advantages are described as followed: low-cost system and fabrication, manufacture, high yield, and suitable for semiconductor process. Using PAECE technology to fabricate wafer through-holes array, we can get the structures with high etching rate and smooth etching sidewall through silicon substrate with thickness of 500 um when the etching time reached 16.7 hours. The smallest width of through-hole by PAECE is 21 um, and the highest aspect ratio is 17.7. The related experimental parameters are described as followed: illumination is 18000-32000 lux, chose surfactants are 1 wt.% DC-1, 1 wt.% MA, 2.5 wt.% H2O2 and 1 wt.% Alcohol. The black micro holes array fabricated by PAECE 2 hr with 1 wt.% MA has ultra-low reflectivity 0.43%, and reflectivity of through-holes array also has equal values about 0.4-05%. Results of this research proved that PAECE technology had been able to partially replace the dry etching technology. It has advantages for applications of integrated probe array and interconnection of wafer-level package. After PAECE fabrication, the black micro holes array will be applied to antireflective structure of solar cell to improve the efficiency obviously.

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Su, Yu-Wei, and 蘇友偉. "The Influence of Wave Parameters on Copper Plating in Through-Holes." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/28995210408987330747.

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碩士
逢甲大學
材料與製造工程所
92
The influence of the square wave and non-square wave on copper plating in through-holes was studied. The thickness of the face and the wall in through-hole was measured by the optical microscope and the differences of the throwing power, the thickness and efficiency of copper deposit in the middle of the barrel between the square wave and non-square wave was analyzed. The back-erode of the reverse plus process was better when the amount of electric charge produced by the square wave was greater than the non-square wave on the reverse current and time. The concentration of copper ions closed to the middle of the barrel was restored quickly, so as to get the better copper plating. The effect was more obvious as the reverse time was longer. In the square wave of reverse pulse plating with Iforward 17 A, Ireverse 34 A, Tforward 20 ms, Treverse 1.6 ms and time of plating with 1800 sec was verified. Therefore can know, on copper plating in the through-holes of the high aspect ratio was influenced by the discrimination of waveform produced by rectifier.

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lee, Szu-Hsien, and 李思賢. "Flat-Plate Film Cooling through Conical Holes with Compound- angle Injection." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/76893616970072695617.

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碩士
國立臺灣大學
機械工程學系
85
To optimize the injection hole geometry for obtaining a better film cooling performance over a flat plate, this paper presents the measured heat transfer and film cooling results over a flat plate as the secondary flow is ejected into the mainstream through a row of conical holes. A transient liquid crystal thermography was employed to obtain the film cooling performance and heat transfer distribution over a flat plate. The conical injection hole with a pitch-to-diameter ratio of 3.0 at the exit plane has aDetailed local heat transfer and film cooling effectiveness distributions for X/d < 20 are presented in this study. Conical geometry with ( = 90 o has the best film cooling protection in the region near injection holes ( X/d < 3 ) among all cases of various injection angles. However, the conical geometry with ( = 0 o has a better overall film cooling performance on the whole test area for X/d < 20 than those with other injection angles or with straight round hole geometry.

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Cheng, Hung-Hsiang, and 鄭宏祥. "Electrical Characterization and Modeling of Plated Through Holes in Organic Substrate." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/n5p74d.

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碩士
國立中山大學
電機工程學系研究所
95
This thesis focuses on the structures of plated through holes in organic substrate, and discusses the high-frequency electrical characteristics of various plated through hole structures. This thesis consists of four parts. The first part introduces various kinds of vias in multilayer substrate. This content includes substrate drilling processes and capabilities, and discussions on plated through hole structures and their manufacture concerns. The second part focuses on actual measurement of plated through holes, and introduces high-frequency double-side probing technique. The difference from traditional high-frequency coplanar probing measurement is also discussed. The third part focuses on the high-frequency simulation by full-wave software – Ansoft HFSS, and discusses the effects of various excited source and model structures on simulations. Part4 focuses on developing the broadband equivalent circuit model based on the physical structures, and discusses the electrical characterization of different plated through holes, and provides the related design concept.

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Kalkum, Felix [Verfasser]. "Efficient light transmission through single sub-wavelength holes / vorgelegt von Felix Kalkum." 2009. http://d-nb.info/1000534677/34.

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Chen, Tsu-Chi, and 陳祖啟. "Effects of Copper Brighteners on Throwing Power and Thermal Reliability of Plating Through Holes." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/31020227311338658064.

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碩士
國立中興大學
化學工程學系所
105
High aspect ratio through holes are commonly designed in printed circuit boards (PCBs) with a high density interconnection. In this study, the PCB sample are metalized by Cu electroless deposition and then by Cu electroplating. When electroplating, adding three different brighteners to achieve high throwing power and good thermal reliability with the plated through holes (PTHs). In this study, using the three different brightener include 3-Mercapo-1-1-Propanesulfonate (MPS)、3-(Amidinothio)-1-propanesulfonic acid (UPS)、Sodium 3-(benzothiazol-2-ylthio)-1-propanesulfonate (ZPS) with the basic electrolyte which are 60g/l copper sulfate、10% sulfuric acid、PEG8000 200ppm and Cl- 60ppm. The electroplating time is 1.5 hours. In the electrochemical experiments, the acceleration effect of adding MPS is the most obvious. The electroplating results shows that adding 1 ppm MPS, or 10 ppm UPS, or 20 ppm ZPS have goof effect for throwing power and thermal shock test. With higher UPS or ZPS concentration adding in the electrolyte, the results show that throwing power decrease and fail thermal shock test. It can be seen that the stress on the copper layer increase with UPS or ZPS adding in the electrolyte. Moreover, the orientation which electroplated copper with UPS or ZPS is prefer <220>, the modulus of elasticity of <220> is lower than <111>, so that the reasons of failing in the thermal shock test are associated to the stress that produced when electroplating and the copper orientation. To achieve high throwing power and pass thermal shock test, different brighteners and concentration are showed in this study. Adding UPS or ZPS in the electrolyte affects the stress on the copper layer and the copper orientation which are the keys to the result of the thermal shock test. Keyword: Copper Plating Brightener, Throwing Power, Thermal Reliability.

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Du, Song Ming. "Fundamental Physics Through Gravitational Waves: From No-Hair Theorem to Quantum Structures of Black Holes." Thesis, 2019. https://thesis.library.caltech.edu/11315/1/songming_du_2018_thesis.pdf.

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In general relativity, black hole is the simplest macroscopic object in the universe: any black hole can be completely described by its mass, charge and angular mo- mentum. However, such a simple picture might be changed if the gravitational field equations are modified or quantum effects are taken into consideration. These additional hairs of black hole, if exist, may provide valuable information to reveal the deepest mystery of the universe: quantum theory of gravity.

In this thesis, we try to relate the hypothetical extra hairs of black hole with the ob- servational evidence as gravitational waves – another prediction of general relativity and are recently detected. In Chapter I, we provide a pedagogical introduction to the black hole hairs introduced by modified gravity and quantum mechanics, and lay out a mathematical framework to describe the gravitational wave emission with the existence of near-horizon quantum hair. In Chapter II we show that in scalar-tensor theory of gravity, the formation process of a black hole from gravitational collapse is accompanied with the emission of scalar hair. This mechanism gives rise to a scalar type memory effect of gravitational wave, which does not exist in general relativity. This phenomenon can further be used to study the parameter space of the scalar-tensor theory. In Chapter III, we find the scalar gravitational memory effect from stellar collapses provide the strongest sources for the stochastic gravita- tional wave background with scalar polarization in Brans-Dicke theory. The energy density spectrum for this background is provided and its model dependencies are studied. In Chapter IV, we provide a Green’s function method to study the echoes, which are the gravitational waves reflected by the quantum hair near the event hori- zon of a black hole. In Chapter V, we build phenomenological models to describe the near-horizon quantum hair and predict its implication to the binary black hole stochastic gravitational wave background. Our study indicates that the existence of the quantum hair will significantly increases such a background and pins down the most relevant model parameter to be the area under the effective potential. Further, we also demonstrate that the result is rather robust against the uncertainties about the nature of the near-horizon quantum hair. In the end, a field theory based treatment to the gravitational waves in general relativity is provided as the appendix.

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Li, Ming-Cheng, and 李明承. "Fabrication of metal micropillars array by integrating photo-assisted electrochemical etching through-holes and electroforming techniques." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/80392370917555913930.

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碩士
國立臺灣師範大學
機電科技研究所
95
This research will integrate photo-assisted electrochemical etching (ECE) and electroforming techniques for fabricating high-density metal micropillars. This process is described as followed: high-density through holes in silicon are etched by photo-assisted electrochemical etching under various paramerers; then the through holes are fully filled by copper electroforming technique to form high-density metal micropillars. The deveploed technology will be promising for the application of integrated probe array and wafer-level package in the further. Because of the above-mentioned, this research used the low-cost electrochemical etching (ECE) equipment developed by ourselves and got the best parameters of the related manufacture. The experiment result proved that the technology had been able to partially replace the dry etching technology. Using the ECE technology to fabricate high aspect of micro-pores array, we can get the structures of high aspect when the etching time reached 31.5 hours. Through-holes were formed by selective partial electropolishing in a 2.5 wt.% HF electrolytic solution, using an N-type, (100)-oriented Si wafer as an anode, and a Pt plate as a cathode. The obtained holes were square through-holes of 40 mm side length, with an aspect ratio of 12.5. Metal micropillars was made by electroforming technology with pulse and reverse current. The height of metal micropillars achieves 500 mm and the aspect ratio cab reach 12.5.

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Chang, Yi-Tsung, and 張議聰. "Extraordinary Transmission of Light through Al(Ag)/Si Structure Perforated with Periodic and Random Distribution of Holes." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/14470205810178401922.

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博士
國立臺灣大學
電子工程學研究所
95
The main contribution of this thesis is the investigation of the light transmission through a metal/dielectric structure perforated with periodic and random distribution of holes on metallic film. In recent year, the effects of surface electric charge field interacted with the localized surface plasmons under the Bragg scattering condition with the light transmission through a structure of periodic metal holes array are extensively studied. But the transmission peak position of the surface plasmon modes in random structure of holes, the propagation length, dispersion relation, the intrinsic damping and radiation damping of surface plasmon have not yet been investigated in detail. To answer these questions, an aluminum metallic film is evaporated on doubly polished Si substrate, then the hexagonally-ordered holes array, superperiodic micro-cell arrays, random distributed holes and micro-cell arrays on aluminum film are formed by lithography, respectively. The optical transmission properties and dispersion relation of surface plasmon are measured and examined by Fourier Transform Infrared (FTIR) spectrometer. The propagation length and the damping of surface plasmon are calculated and analyzed in details. The dispersion relation of surface plasmon polariton of hexagonally-ordered holes array is measured, it is found that as the light was normally incident onto the sample, the (1,0) Al/Si surface plasmon modes split into two peaks in the transmission spectra, and this effect is most obvious when the diameter of the hole is close to a half of the lattice constant. At larger incident angles, the six degenerate (1,0) Al/Si surface plasmon modes split into three or four modes depending on the symmetry axis, even higher-order surface plasmon modes can be identified for small hole diameters. As to the superperiodic micro-cell arrays, the transmission spectra and dispersion relation of surface plasmon polariton indicated the surface plasmons are generated by Fabry-Perot type waveguide resonances with different integer order. The ratio of periodicity between the super-periodic structure p and the N*N micro-cell d determines the integer order (where N is the number of isolated holes, N= 3, 4 and 5), and suggest that the surface plasmons are Fabry-Perot type resonance within a super unit cell. As to the random distributed holes, the transmission spectra and dispersion relation of surface plasmon polariton suggest that the primary (1,0) Al/Si surface plasmon mode is determined by the nearest neighbor distance in a cluster of random distributed holes, the intensity of transmission peak and the full width at half maximum (FWHM) is determined by the size and number of random distributed holes, and even surface plasmon modes of other distributed distance can be identified as well. When the light incident angle increases, the degenerate surface plasmon mode can not be observed in the dispersion relation, it is owing to the fact that the number of random distributed holes becomes less. As to the micro-cell arrays with random distribution, the transmission spectra and dispersion relation of surface plasmon polariton indicate that as the period of micro-cells is changed, the transmission peaks also changes, it can be exploited to the application of the infrared wavelength-selective devices.

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Chang, Yi-Tsung. "Extraordinary Transmission of Light through Al(Ag)/Si Structure Perforated with Periodic and Random Distribution of Holes." 2007. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2006200715042000.

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32

Yang, Ying-Tsung, and 楊英琮. "A Study of Development of Micro fluidics -Chips with Micro Channels and Through Holes by LIGA and Thermoplastic Injection Molding." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/41645522885762119873.

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碩士
國立雲林科技大學
機械工程系碩士班
93
This study focus on manufacturing bio-chips within micro channels and through holes. It is an integration of UV-LIGA and micro molding processes. The micro mold has been designed and analyzed by the mold filling simulation first. In order to mold a plate with through holes, the mold should have micro pillars in one side and mapping micro holes in the other side. The micro pillar array can be fabricated by the UV-LIGA, and later it would be used to manufacture micro holes in the other mold half by M-EDM. Micro injection molding was used to produce low-cost，high-precision，and high-value products. Both micro and nano technology help develop products toward more slight、more thin、and smaller. It is great importance to decrease the dimensions of biochips and to have them mass-produced and decrease cost. This project used UV-LIGA technology to manufacture microstructure instead of traditional technology and used the injection molding method to produce biochips instead of hot-press method. Because the structure and dimensions are getting more and more complicated. CAE method is used to help predict the quality of product and improve the weakness before molding. Since the thicknesses of the product and gates become more thinner , the time for the melt to solidify becomes much shorter. Higher injection rate is regarded, and it is very important for our experimental observation & simulation results in order to prevent short-shot of the product.In this thin wall molding case, the effect of holding time is much less significant on the shrinkage due to very fast solidification. The temperature is also an important factor that will affect the quality of products.The shrinkage of dimensions will increase when we use higher mold temperature, but it could improve the degree of replication of microstructures .

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Chen, Ming-yu, and 陳明玉. "Exploring the Theme of Adolescent Identity through Task-Based Instruction in Taiwan EFL Setting: A Case Study on Salinger’s Catcher in the Rye and Sachar's holes and Small steps." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/23778145016927572813.

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碩士
國立彰化師範大學
英語學系
98
This thesis proposes to teach the theme of adolescent identity in Salinger’s Catcher in the Rye and Sachar’s Holes and Small Steps through literature-based, task-based instruction which especially targets speaking activities in Taiwan EFL context. It first focuses on the characteristics, importance, as well as appropriateness of young adult literature in a literature-based classroom. Next, it introduces theoretical backgrounds and pedagogical application of literature-based instruction and task-based instruction in a language-learning environment. In terms of literature-based instruction, it aims to engage learners in the proper use of literary materials in the classrooms and attempts to engage learners in active reading of literature through which learners can acquire language competence, critical thinking skills and further advance to become lifelong readers as well. In terms of task-based instruction (TBI) the goal is to immerse learners in a meaningful, communicative and contextualized learning environment which is learner-centered and whose ultimate goal is to achieve real-world communicative competence. This thesis then outlines a set of activities in the language classroom which are sequenced to investigate the issues of adolescent identity which each protagonist encounters. The theme of identity has always been decisive for young learners who are on the cusp of major life developments. In these three stories, learners are expected to identify “turning points” and other relevant issues influential to protagonists’ identity development. Learners can thus advance to greater self awareness and personal growth. Communicative activities centering on the theme of adolescent identity aim to help learners not only achieve language competence but also evoke personal responses in a contextualized language-learning environment. The ultimate goal of this model of learning is that students can become proficient learners, passionate lovers of literature, and better critical thinkers.

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