Academic literature on the topic 'Bingham, Seth, Bingham, Seth'

Judul penelitian ”Kontribusi Media Watch Pada Kemer d ekaa Pners Di Era Re formas in” i, bertujuan mengetahui sebe rap jaauh media watch memberikan kontribusi terhadap kemer dekaa pners Indonesia yang telah memperoleh kembali ke b ebasanny as, etelah dalam pemerintahan orde baru, pers merasa dibatasi kebe b asa nny aT.ernyata, sete la hpers memperoleh kembali kebe basanny ay,ang terjadi adalah ber bag akionflik, antara pers dengan pejabat maupun pers dengan masyarakat. Pemberitaan yang disajikan pers cenderung sepihak, tidak melakukan check and rec heck, dan menga baika ncover both side. Kondisi ini ter ja dkiarena kurang pahamnya pengelola media terhadap cara bermedia yang benar, serta kurang ketatnya kon tr oplemberitaan oleh komisi-komisi pengawas media yang telah dibentuk, seperti Dewan Pers dan Komisi Penyiaran Indonesia. Menyi ka pi kondisi ini, mun c ullembaga-lembaga swa d ay amasyara k at(LSM) yang menempat ka dniri sebagai pengawas me d idaengan nama Media Watch. Metode penelitian ini diskriptif kualitatif de nga mn engungkap peris tiw aatau kejadian yang menimpa pers Indonesia di era reformasi. Hasil penelitian menyebutkan media watch memberikan kontribusi dengan menyadar ka npers maupun ma sy araka t, tentang penting ny baermedia yang baik, berupa bim binga tnentang etika pro fe si ke w ar t awnaa nt,atacara pe nyampaia bne ri tyaang sesuai dengan kode etik, serta me n ging atka nb, ahwa pers mempunyai tugas utama seba g aliembaga kontrol so sia yl,ang konstruktif, yang dapat merangsang masyara k autntuk beropini dan ber e ksp re sik,arena dalam sistem demokrasi masyara k amt empunyai hak untuk tahu serta hak untuk berekspresi. Kata kunci : Media Watch, Kemerdekaan Pers, Era Reformasi

The objective of this thesis is to develop and evaluate a methodology for the solution of the Navier-Stokes equations for Bingham Herschel-Bulkley viscoplastic fluids using stabilized mixed velocity/pressure finite elements. The theoretical formulation is developed and implemented in a computer code. Numerical solutions for these viscoplastic flows are presented and assessed. Viscoplastic fluids are characterized by minimum shear stress called yield stress. Above this yield stress, the fluid is able to flow. Below this yield stress, the fluid behaves as a quasi-rigid body, with zero strain-rate. First, the Navier-Stokes equations for incompressible fluid and two immiscible fluids considering free surface are presented. A review of the Newtonian and non-Newtonian rheological models is included, with a detailed description of the viscoplastic models. The regularized viscoplastic models due to Papanastasiou are described. Double viscosity regularized models are proposed. The analytical solutions for parallel flows are deduced for Newtonian, Bingham, and Herschel-Bulkley, pseudoplastic and dilatant fluids. The discrete model is developed, and the Algebraic SubGrid Scale (ASGS) stabilization method, the Orthogonal Subgrid scale (OSS) method and the split orthogonal subscales method are introduced. For the cases of flows with a free surface, the simplified Eulerian method is employed, with the level set method to solve the motion of the free. A convergence study is performed to compare the ASGS and OSS stabilization methods in parallel flows with Bingham and Herschel-Bulkley fluids. The double viscosity regularized models show lower convergence error convergence than the regularized models used commonly. Numerical solutions developed in this thesis are applied to a broad set of benchmark problems. They can be divided into three groups: Bingham flows, Herschel-Bulkley flows and free surface flows. The solutions obtained validate the methodology proposed in this research and com-pare well with the analytical and numerical solutions, experimental and field data. The methodology proposed in this thesis provides a computational tool to study con-fined viscoplastic flows, common in industry, and debris viscoplastic flows with free surface.
El objetivo de esta tesis es formular y evaluar una metodología para la resolución de las ecuaciones de Navier-Stokes para los fluidos viscoplásticos de Bingham y de Herschel-Bulkley mediante el método de los elementos finitos mixtos estabilizados velocidad/presión. Se desarrolla una formulación teórica, se realiza la implementación computacional y se presentan y evalúan soluciones numéricas para estos fluidos viscoplásticos. Los fluidos viscoplásticos se caracterizan por presentar una tensión de corte mínima, denominada tensión de fluencia. Por encima de esta tensión de corte mínima el fluido comienza a moverse. En caso de no superarse esta tensión de fluencia, el fluido se comporta como un cuerpo rígido o quasi-rígido, con velocidad de deformación nula. Se presentan inicialmente las ecuaciones de Navier-Stokes para un fluido y dos fluidos incompresibles e inmiscibles considerando superficie libre. Se presenta una revisión de los modelos reológicos Newtonianos y los modelos no-Newtonianos. Se hace una descripción detallada de los modelos viscoplásticos. Se describen los modelos viscoplásticos regularizados de Papanastasiou. Se proponen modelos regualarizados de doble viscosidad como alternativa a los comúnmente usados. Se deducen las soluciones analítica en flujos paralelos para el fluido Newtoniano, el fluido de Bingham, de Herschel-Bulkley, el fluido pseudoplástico y dilatante. Se desarrolla el modelo discreto, así como la formulación estabilizada con los métodos de subescalas algebraica (Algebraic subgrid scale, ASGS), de subescalas ortogonales (Orthogonal subgrid scale, OSS) y de subescalas ortogonales con la presión y el termino convectivo desacoplados, split-OSS. En el caso del fluido con superficie libre se presenta el método euleriano simplificado, el cual usa el método de superficie de nivel level set para resolver el movimiento de esta superficie libre. Se presenta un estudio de convergencia con los métodos de estabilización OSS y ASGS en los flujos paralelos de Bingham y de Herschel-Bulkley. Los modelos regularizados de doble viscosidad muestran menor error de convergencia que los usados regularmente. Se presentan las soluciones numéricas desarrolladas en esta tesis para un amplio conjunto de problemas benchmark. Pueden dividirse en tres grupos: flujos de Bingham, flujos de Herschel-Bulkley y flujos con superficie libre. Las soluciones obtenidas validan la metodología propuesta en este trabajo de investigación comparándose muy bien con las soluciones analíticas, numéricas, con resultados experimentales y datos de campo. La metodología propuesta en esta tesis proporciona una herramienta computacional para estudiar flujos viscoplásticos confinados, muy comunes en la industria, y los flujos detríticos viscoplásticos con superficie libre.

Thesis (D.M.A.)--University of Nebraska-Lincoln, 2010.
Title from title screen (site viewed July 8, 2010). PDF text: v, 81 p. : ill., music ; 555 K. UMI publication number: AAT 3398350. Includes bibliographical references. Also available in microfilm and microfiche formats.

This chapter describes social-coercion theory as conceptualized by Paul Bingham and Joanne Souza. This theory, which pertains to the evolution of human uniqueness, helps us understand how humans evolved to coordinate social activities in small non–kin-based groups. The tendency of humans to form such coordinated alliances is a foundational part of our evolutionary history that sets us apart from other apes in important ways. Further, this theory can help us understand the emergence of democracy and egalitarianism as basic aspects of the human social world. Understanding the principles that underlie this theory can help us understand factors associated with positive functioning in human communities.

A numerical method to determine the velocity field, and related variables, in plastic flow in non-circular straight ducts is presented. The method is an extension of previous work of the senior author related to modeling laminar flow in pipes of arbitrary cross-sectional contours using natural coordinates. In this case the concept of “natural coordinates” is applied to the system of orthogonal curves determined by the plane isovels and their normal counterparts. The momentum equation for the axial velocity is expressed in natural coordinates in which one relevant variable is the radius of curvature of isovels. The method is applied to a selected set of shapes when the fluid is a Bingham plastic. Isovels and plug zones are determined drawing on the properties of the isolvels and normal curves. Computations start at the pipe perimeter and advance toward the center.

Semi-active isolators offer significant improvement in performance over passive isolators. These systems benefit from the advantages of active systems with the reliability of the passive systems. In this work we study a vibration isolation system with a magnetorheological (MR) damper. The experimental investigation of the mechanical properties of a commercially available linear MR damper (RD-1005-3) was conducted next. The mathematical Bouc-Wen model was adopted to predict the performance of MR damper. In addition, a modified Bingham model has been developed to characterize the damper behavior more accurately and efficiently. The measured hysteresis characteristics of field-dependent damping forces are compared with the simulation results from the described mathematical models. The accuracy of a damping-force controller using the proposed method is also demonstrated experimentally. Finally, a scaled quarter car model is set up to study the performance of the control strategy. The experimental results show that with the semi-active control the vibration of the quarter car model is well controlled.

One factor limiting the production rate of radioactive waste immobilization processes is the rheological limitations imposed by the design of remotely maintained slurry process equipment (i.e. pumps, piping). Rheology modifiers (dispersants/flocculants) that could potentially decrease the yield stress and/or plastic viscosity of radioactive waste slurries were tested on simulated waste to determine which provided the largest decrease in yield stress and plastic viscosity. The goals of this study were to: 1) determine if trace levels of chemical additives could be used to reduce the rheological characteristics of radioactive waste slurries, 2) identify potential chemical additives for this work and future testing, 3) test a limited set of chemical additive candidates on simulated radioactive wastes, and 4) develop advanced techniques to visualize the internal slurry structure and particle-particle interaction within the slurry. Radioactive wastes slurries generated from the production of plutonium and tritium during the Cold War are being (and will be) immobilized in a borosilicate glass matrix using joule heated glass melters at various Department of Energy (DOE) facilities located across the United States. The maximum insoluble solids content of the waste slurries is limited by the design-basis rheological properties (e.g. the Bingham plastic yield stress and plastic viscosity) used to design the slurry handling systems. It is possible to modify the equipment used to mix, sample, and transport the waste slurry. However, the design and construction cost for any such modifications is very high due to the constraints (radiation, non-visible remote operation) imposed on the design and operation of radioactive waste processes. The rheology of two slurries with various rheology modifiers was evaluated using a conventional concentric cylinder rheometer (Haake Rheometer RS150). Only one rheology modifier of those tested was found to decrease the apparent viscosity of the waste slurry by any significant amount and several of the modifiers tested produced the opposite effect. Duramax D-3005 was found to decrease the Bingham Plastic yield stress of simulated radioactive waste slurries by approximately 18%. Selected slurries were further analyzed by a laser scanning confocal microscope. This technique allows the slurry to be analyzed in an unaltered condition. The microscope has the ability to make both two-dimensional pictures and three-dimensional representations of the slurry’s internal structure. The microscope allows the user to understand how particles are flocculated or dispersed throughout a concentrated suspension of heterogeneous simulated nuclear waste slurries.