16,336 research outputs found
Grand Rounds Research Reproducibility - Matt Haber, PhD (03-27-2018)
No full textSpencer S. Eccles Health Sciences Library Grand Rounds: Research Reproducibility (GRRR). "Positively Misleading Errors" presented by Matt Haber, PhD, Chair Department Of Philosophy and Center for Quantitative Biology, University of Utah. GRRR is a weekly endeavor to raise awareness about reproducibility issues, showcase Utah researchers\u27 work, and to create an open forum for discussions. Grand Rounds: Research Reproducibility website: http://campusguides.lib.utah.edu/UtahRR18/GRRR Matt Haber, PhD: bit.ly/MattHaberUof
Brownian Motion of Continuous Deformable Bodies
No full textThe fluctuations of continuous elastic bodies are studied, applying the equipartition principle of energy to each normal mode of vibration. The mean square displacement of the particles from their equilibrium configurations is expressed through an infinite series, which is always converging, provided that the elasticity condition is satisfied even at high modes of vibration
Boundary Conditions for Darcy's Flow through Porous Media
No full textA novel formulation for the boundary conditions to be applied at a porous surface is proposed. Interfaces between porous and clear media and porous and solid media are considered. The well known Beavers & Joseph boundary condition is applicable for interfaces betweeen porous and clear media. An equivalent boundary condition is obtained for interfaces between porous and impermeable media, namely v_n = sqrt(k) nabla_t v_t, where v is the velocity field inside the porous medium, the subscripts n and t refer to components normal and tangential to the interface, respectively, while k stands for the permeability. A sample problem is solved for the flow fields exterior to a porous spherical particle and interior to it, assuming that the particle has a rigid concentric core and that the submerging flow field is Newtonian, Stokesian and uniform at infinity. Both Brinkman's equation and Darcy's law are utilized to obtain general forms of the velocity and pressure fiels. Comparison of the two solutions yields the desired boundary conditions applicable to the Darcy problem
Time-Dependent Dispersion of Small Particles in Rectangular Conduits
No full textThe mean velocity and dispersion coefficient of a Brownian particle suspended in a fluid flowing in a rectangular conduit are evaluated, obtaining analytical results over the whole time domain and for any initial position of the particle. These new results are obtained by exploiting the symmetry of the problem, showing that the particle longitudinal motion within the rectangular conduit is equivalent to the one occurring in an unbounded velocity field, which is the even periodic extension of the original velocity profile. Two main parameters are encountered: the aspect ratio eta of the conduit cross section, and the nondimensional time tau_y, scaled by the characteristic time associated with the particle molecular diffusion. Simple asymptotic expressions are obtained for the particle velocity and displacement, the velocity auto-correlation, and the dispersion coefficient. The limits addressed are for small and large times tau_y and small eta ratios. The main results are the following. In the limit of long times the mean displacement strongly depends on the initial position ofthc particle, while the dispersion coefficient is independent of it and, for a fixed cross section area, it attains a maximum value at eta = 0.65. In the limit of vanishingly small eta two distinct timescales tau_y, and tau_z = tau_y/eta^2 are defined, characterizing the particle molecular diffusion along the short and the long side of the conduit cross section, respectively. It is found that for short times t tau_z, it attains a new higher limit value. While the long-time limit value is independent of the initial location of the Brownian particle and is about 7.95 times higher than the two-dimensional dispersivity, the intermediate-time plateau strongly depends on the initial conditions. Namely, when the particle initial location is not too close to the short lateral wall the intermediate-time dispersion coefficient coincides with the two.dimensional dispersivity, indicating that the particle does not "know" of the existence of the lateral boundary. However, when the particle is initiallv introduced near the lateral wall, the intermediate-time dispersion coefficient is higher and is equal to up to four times the two-dimensional value
Lagrangian Approach to Laminar Dispersion in Rectangular Conduits
No full textTime-dependent mean velocities and dispersion coefficients are evaluated for a general two-dimensional laminar flow. A Lagrangian method is adopted by which a Brownian particle is traced in an artificially restructured velocity field. Asymptotic expressions for short, medium and long periods of time are obtained for Couette flow, plane Poiseuille flow and open-channel flow over an inclined flat surface. A new formula is suggested by which the Taylor dispersion coefficient can be evaluated from purely kinematic considerations. Within an error of less than one percent over the entire time domain and for various flow fields, a very simple analytical expression is derived for the time-dependent dispersion coefficient D(t) = D + D^T [1 - (1 - e^(-at))/(at)] where D is the molecular diffusion coefficient, D^T denotes the Taylor dispersion coefficient, t stands for the non-dimensional time pi^2 Dt/Y^2, Y is the distance between walls and a = (N+1)^2 is an integer which is determined by the number of symmetry planes N that the flow field possesses. For Couette and open-channel flow there are no plane of symmetry and a = 1; for Poiseuille flow there is one plane of symmetry and a = 4
Applications of Wiener's Path Integral for the Diffusion of Brownian Particles in Shear Flows
No full textWiener's path integral theory is revisited, stressing that it holds only when the condition of local equilibrium is fulfilled. The diffusion of a particle in a two and three-dimensional shear flow is studied, showing that for small time intervals the particle diffuses freely, without being influenced by the velocity gradient of the incident flow, while for long time intervals it exhibits a time dependent dispersion coefficient
Haber Metinlerinin Kategorizasyonunda Varlık Isimleri ve Konu Başlıkları Ilişkisi
No full textWith text categorization it is possible to access information within a large pile of impure data. It also helps people to save time who wants to have information more easily and practically. One of the most important practical research areas in terms of text categorization is news, as it has a potential of rapid increase. This thesis aims to investigate the connection of subject codes with named entities, in terms of text categorization, by using 5834 news texts which were obtained from BilCol-2005 news corpus. To address this, 5834 news were tagged with seven different named entities (person, organization, location, date, time, money and percentage). Tagged news were classified under 13 different subject codes of IPTC s (International Press Telecommunications Council) main subject taxonomies. The investigation was based on tagged and untagged words and their relations with the IPTC news codes. Key findings were revealed with the frequency and percentage values along with some statiMetin kategorizasyonu ile büyük ve kirli veri yığınlarının içerisindeki bilgiler düzenlenerek bilgiye erişim kolay ve pratik hale gelmektedir. Metin kategorizasyonu ayrıca, bilgiye ihtiyaç duyan kişilerin istedikleri bilgiye erişmelerinde zaman kazandırmak açısından da son derece önemlidir. Haber metinleri gibi hızlı artış potansiyeline sahip olan yapılar metin kategorizasyonuna ihtiyaç duyulan önemli uygulama alanlarından biridir. Bu çalışmada, BilCol-2005 Türkçe haber derleminden sağlanan 5834 haber kullanılarak, haber metinlerinin kategorizasyonunda varlık isimleri (named entities) ve konu başlıkları ilişkisinin incelenmesi amaçlanmıştır. Buna yönelik olarak 5834 haber yedi farklı varlık ismi (kişi, kurum, konum, tarih, zaman, para ve yüzde) ile etiketlenmiştir. Etiketlenen haberler IPTC (International Press Telecommunications Council) temel düzey konu başlıkları taksonomisine göre kategorize edilmiş ve derlem 13 farklı IPTC konu başlığı ile tanımlanmıştır. Bu doğrultuda gerçekl
Electrified Haber-Bosch Process: Green Ammonia Production
No full textThis report provides a design for a new process to make the ammonia-producing Haber-Bosch process more sustainable by reducing its CO2 emissions. It presents different elements of a process design with most importantly; process diagrams, mass and energy balances and a techno-economic analysis. The most important differences in this process is the use of water electrolysis and nitrogen production. This process emits approximately 50% less CO2 than regular Haber-Bosch methods. Nevertheless, the techno-economic analysis shows that this method is very expensive and that ammonia can only be sold at an acceptable price conform to the market with subsidies on electricity prices and can only become competitive if CO2 taxes are implemented for classic Haber-Bosch plants.Renewables Based Energy Conversion and StorageWB3595 Design ProjectMechanical Engineering | Process and Energy Technolog
A note on a paper by S. Haber
No full textA technique used by S. Haber to prove an elementary inequality is applied
here to obtain a more general inequality for convex sequences
Literatura que entiende: Yo no tengo la culpa de haber nacido tan sexy de E. Mendicutti y las identidades transgresoras
No full textQueering literature: E. Mendicutti’s Yo no tengo la culpa de haber nacido tan sexy and transgressive identitiesThis paper focuses on camp characteristics of Eduardo Mendicutti’s novel Yo no tengo la culpa de haber nacido tan sexy and analyses the construction of gender identity of its transsexual protagonist. It also studies the way intertextual el ements are used by the author to queer the literary tradition of the Spanish Golden Age.Queering literature: E. Mendicutti’s Yo no tengo la culpa de haber nacido tan sexy and transgressive identitiesThis paper focuses on camp characteristics of Eduardo Mendicutti’s novel Yo no tengo la culpa de haber nacido tan sexy and analyses the construction of gender identity of its transsexual protagonist. It also studies the way intertextual el ements are used by the author to queer the literary tradition of the Spanish Golden Age
- …
