A random number generator for continuous random variables

A FORTRAN 4 routine is given which may be used to generate random observations of a continuous real valued random variable. Normal distribution of F(x), X, E(akimas), and E(linear) is presented in tabular form

About the ergodic regime in the analogical Hopfield neural networks. Moments of the partition function

In this paper we introduce and exploit the real replica approach for a minimal generalization of the Hopfield model, by assuming the learned patterns to be distributed accordingly to a standard unit Gaussian. We consider the high storage case, when the number of patterns is linearly diverging with the number of neurons. We study the infinite volume behavior of the normalized momenta of the partition function. We find a region in the parameter space where the free energy density in the infinite volume limit is self-averaging around its annealed approximation, as well as the entropy and the internal energy density. Moreover, we evaluate the corrections to their extensive counterparts with respect to their annealed expressions. The fluctuations of properly introduced overlaps, which act as order parameters, are also discussed.Comment: 15 page

Optimization of graphene-based materials outperforming host epoxy matrices

The degree of graphite exfoliation and edge-carboxylated layers can be controlled and balanced to design lightweight materials characterized by both low electrical percolation thresholds (EPT) and improved mechanical properties. So far, this challenging task has been undoubtedly very hard to achieve. The results presented in this paper highlight the effect of exfoliation degree and the role of edge-carboxylated graphite layers to give self-assembled structures embedded in the polymeric matrix. Graphene layers inside the matrix may serve as building blocks of complex systems that could outperform the host matrix. Improvements in electrical percolation and mechanical performance have been obtained by a synergic effect due to finely balancing the degree of exfoliation and the chemistry of graphene edges which favors the interfacial interaction between polymer and carbon layers. In particular, for epoxy-based resins including two partially exfoliated graphite samples, differing essentially in the content of carboxylated groups, the percolation threshold reduces from 3 wt% down to 0.3 wt%, as the carboxylated group content increases up to 10 wt%. Edge-carboxylated nanosheets also increase the nanofiller/epoxy matrix interaction, determining a relevant reinforcement in the elastic modulus

Charge and matter distributions and form factors of light, medium and heavy neutron-rich nuclei

Results of charge form factors calculations for several unstable neutron-rich isotopes of light, medium and heavy nuclei (He, Li, Ni, Kr, Sn) are presented and compared to those of stable isotopes in the same isotopic chain. For the lighter isotopes (He and Li) the proton and neutron densities are obtained within a microscopic large-scale shell-model, while for heavier ones Ni, Kr and Sn the densities are calculated in deformed self-consistent mean-field Skyrme HF+BCS method. We also compare proton densities to matter densities together with their rms radii and diffuseness parameter values. Whenever possible comparison of form factors, densities and rms radii with available experimental data is also performed. Calculations of form factors are carried out both in plane wave Born approximation (PWBA) and in distorted wave Born approximation (DWBA). These form factors are suggested as predictions for the future experiments on the electron-radioactive beam colliders where the effect of the neutron halo or skin on the proton distributions in exotic nuclei is planned to be studied and thereby the various theoretical models of exotic nuclei will be tested.Comment: 26 pages, 11 figures, 3 tables, accepted for publication in Phys. Rev.

Superscaling and Neutral Current Quasielastic Neutrino-Nucleus Scattering beyond the Relativistic Fermi Gas Model

The superscaling analysis is extended to include quasielastic (QE) scattering via the weak neutral current of neutrinos and antineutrinos from nuclei. The scaling function obtained within the coherent density fluctuation model (used previously in calculations of QE inclusive electron and charge-changing (CC) neutrino scattering) is applied to neutral current neutrino and antineutrino scattering with energies of 1 GeV from $^{12}$C with a proton and neutron knockout (u-channel inclusive processes). The results are compared with those obtained using the scaling function from the relativistic Fermi gas model and the scaling function as determined from the superscaling analysis (SuSA) of QE electron scattering.Comment: 10 pages, 6 figures, published in Phys. Rev.

Application of the Design Structure Matrix (DSM) to the real estate development process using modular construction methods

Thesis (S.M. in Real Estate Development)--Massachusetts Institute of Technology, Program in Real Estate Development in Conjunction with the Center for Real Estate, 2012.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (p. 111-112).Real estate development (RED) has traditionally been a very dynamic business, where real estate developers strive to turn an idea into a real asset, by delivering a quality project on time and on budget. In recent years, Modular Construction Methods (MCM) has arisen as an innovative solution to commercial RED projects that require higher levels of the three aforementioned factors, with a special emphasis placed on time. The purpose of our thesis is to explain MCM and its impact on RED by analyzing the interdependent relationships between the different tasks performed during the course of a development. We have accomplished this by using the Design Structure Matrix (DSM), a systems engineering tool, to map out the dependencies between development tasks in a graphical manner. To develop our DSM model for an RED process that uses MCM we conducted interviews with the senior management at RJ Finlay, a New Hampshire based full service real estate firm and Keiser Industries, a modular manufacturing company that operates in Maine and is owned by RJ Finlay. To fully understand the real application of the MCM process to RED, we met with the general contractor, lead architect and project management team for 30 Haven, a commercial RED that uses MCM. 30 Haven is located in Reading, Massachusetts and has been co-developed through an integrated project delivery (IPD) process by RJ Finlay and Oaktree development, using an in-house general contractor and Keiser Industries as its modular manufacturer. Our interviews occurred weeks before the project was completed in the summer of 2012. This allowed us to interview the involved parties about the whole process from inception to construction completion. This helped us further understand the actual problems a RED process using MCM can face throughout the preconstruction and construction processes. We then developed a DSM that showcases the different stages that a RED process using MCM have to go through and the planned and unplanned iterative processes for each stage. Planned iterations are feedback loops between tasks that are meant to rework tasks that forcibly need it, while unplanned iterations reflect feedback loops that occur because of unexpected events. Our thesis has focused on proposing proactive solutions to the unexpected events (referred to as "failure modes") a RED process using MCM can face, by either eliminating them or minimizing their likelihood and impact. The DSM helped facilitate the development of both a normative model and an optimal one, where our solutions for the unplanned iterations were applied. We complemented our findings with a hypothetical financial model that uses the normative and optimal DSM models to show the difference between both in terms of the returns, time and cost for a generic multifamily RED that uses MCM.by Steven V. Bonelli and Adrián M. González Guerra.S.M.in Real Estate Developmen