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Earthquake Engineering & Structural Dynamics 1972 - 1975: Volume 1-3 , Issue Index. Digitized from IA1532427-06 . Next issue: sim_earthquake-engineering-structural-dynamics_july-september-1972_1_1 .

Earthquake Engineering & Structural Dynamics 1972 - 1975: Volume 1-3 , Issue Index. Digitized from IA1532427-06 . Next issue: sim_earthquake-engineering-structural-dynamics_july-september-1972_1_1 .

Earthquake Engineering & Structural Dynamics 1972 - 1975: Volume 1-3 , Issue Index. Digitized from IA1532427-06 . Next issue: sim_earthquake-engineering-structural-dynamics_july-september-1972_1_1 .

Earthquake Engineering & Structural Dynamics 1972 - 1975: Volume 1-3 , Issue Index. Digitized from IA1532427-06 . Next issue: sim_earthquake-engineering-structural-dynamics_july-september-1972_1_1 .

The initial co-sponsored Air Force Systems Command/Naval Material Command Science and Engineering Symposium was held at the Naval Amphibious Base, Coronado on 16 - 19 October 1978. The theme of the 1978 Symposium was "Advanced Technologies - Key to Capabilities at Affordable Cost." The objectives of this first joint Navy/Air Force Science and Engineering Symposium were to: Provide a forum for military and civilian laboratory scientific and technical researchers to demonstrate the spectrum and nature of 1978 achievements by their services in the areas of Armament, Human Resources, Avionics, Materials, Basic Research, Propulsion, and Flight Dynamics.

This study formulates a methodology for evaluating alternative proposals to alleviate the Air Force's Development Engineering (28XX) officer shortage. Compensation was selected as the decision variable from 18 factors related to engineering officer career intent. A compendium of pertinent studies reviewed was also provided. The 28XX officer response to the most recent Air Force Quality of Life Survey indicate that salary has substantial influence on career motivation. The value, or productive capacity of the 28XX officer force was assumed to be a function of the numbers of Lieutenants, Captains, and Field Grade Officers assigned. Data elicited from an experienced Development Engineering officer were fit to a second-order polynomial using stepwise regression to provide an approximate ordinal indicator of relative productive capacity. A System Dynamics model was constructed to provide force and cost projections based upon exogeneous inputs of the future demand for engineers and salary policies. The model's accession and retention rates respond positively to increases in the ratio of future expected military pay to future expected civilian pay. Uses of the model were illustrated, but more extensive validation and parameter estimation is required before the model can be used with confidence in formulating policies. (Author)

This study formulates a methodology for evaluating alternative proposals to alleviate the Air Force's Development Engineering (28XX) officer shortage. Compensation was selected as the decision variable from 18 factors related to engineering officer career intent. A compendium of pertinent studies reviewed was also provided. The 28XX officer response to the most recent Air Force Quality of Life Survey indicate that salary has substantial influence on career motivation. The value, or productive capacity of the 28XX officer force was assumed to be a function of the numbers of Lieutenants, Captains, and Field Grade Officers assigned. Data elicited from an experienced Development Engineering officer were fit to a second-order polynomial using stepwise regression to provide an approximate ordinal indicator of relative productive capacity. A System Dynamics model was constructed to provide force and cost projections based upon exogeneous inputs of the future demand for engineers and salary policies. The model's accession and retention rates respond positively to increases in the ratio of future expected military pay to future expected civilian pay. Uses of the model were illustrated, but more extensive validation and parameter estimation is required before the model can be used with confidence in formulating policies. (Author)

We consider a one-dimensional gas of cold atoms with strong contact interactions and construct an effective spin-chain Hamiltonian for a two-component system. The resulting Heisenberg spin model can be engineered by manipulating the shape of the external confining potential of the atomic gas. We find that bosonic atoms offer more flexibility for tuning independently the parameters of the spin Hamiltonian through interatomic (intra-species) interaction which is absent for fermions due to the Pauli exclusion principle. Our formalism can have important implications for control and manipulation of the dynamics of few- and many-body quantum systems; as an illustrative example relevant to quantum computation and communication, we consider state transfer in the simplest non-trivial system of four particles representing exchange-coupled qubits.

We consider a one-dimensional gas of cold atoms with strong contact interactions and construct an effective spin-chain Hamiltonian for a two-component system. The resulting Heisenberg spin model can be engineered by manipulating the shape of the external confining potential of the atomic gas. We find that bosonic atoms offer more flexibility for tuning independently the parameters of the spin Hamiltonian through interatomic (intra-species) interaction which is absent for fermions due to the Pauli exclusion principle. Our formalism can have important implications for control and manipulation of the dynamics of few- and many-body quantum systems; as an illustrative example relevant to quantum computation and communication, we consider state transfer in the simplest non-trivial system of four particles representing exchange-coupled qubits.

We consider a one-dimensional gas of cold atoms with strong contact interactions and construct an effective spin-chain Hamiltonian for a two-component system. The resulting Heisenberg spin model can be engineered by manipulating the shape of the external confining potential of the atomic gas. We find that bosonic atoms offer more flexibility for tuning independently the parameters of the spin Hamiltonian through interatomic (intra-species) interaction which is absent for fermions due to the Pauli exclusion principle. Our formalism can have important implications for control and manipulation of the dynamics of few- and many-body quantum systems; as an illustrative example relevant to quantum computation and communication, we consider state transfer in the simplest non-trivial system of four particles representing exchange-coupled qubits.

We consider a one-dimensional gas of cold atoms with strong contact interactions and construct an effective spin-chain Hamiltonian for a two-component system. The resulting Heisenberg spin model can be engineered by manipulating the shape of the external confining potential of the atomic gas. We find that bosonic atoms offer more flexibility for tuning independently the parameters of the spin Hamiltonian through interatomic (intra-species) interaction which is absent for fermions due to the Pauli exclusion principle. Our formalism can have important implications for control and manipulation of the dynamics of few- and many-body quantum systems; as an illustrative example relevant to quantum computation and communication, we consider state transfer in the simplest non-trivial system of four particles representing exchange-coupled qubits.

We consider a one-dimensional gas of cold atoms with strong contact interactions and construct an effective spin-chain Hamiltonian for a two-component system. The resulting Heisenberg spin model can be engineered by manipulating the shape of the external confining potential of the atomic gas. We find that bosonic atoms offer more flexibility for tuning independently the parameters of the spin Hamiltonian through interatomic (intra-species) interaction which is absent for fermions due to the Pauli exclusion principle. Our formalism can have important implications for control and manipulation of the dynamics of few- and many-body quantum systems; as an illustrative example relevant to quantum computation and communication, we consider state transfer in the simplest non-trivial system of four particles representing exchange-coupled qubits.

We consider a one-dimensional gas of cold atoms with strong contact interactions and construct an effective spin-chain Hamiltonian for a two-component system. The resulting Heisenberg spin model can be engineered by manipulating the shape of the external confining potential of the atomic gas. We find that bosonic atoms offer more flexibility for tuning independently the parameters of the spin Hamiltonian through interatomic (intra-species) interaction which is absent for fermions due to the Pauli exclusion principle. Our formalism can have important implications for control and manipulation of the dynamics of few- and many-body quantum systems; as an illustrative example relevant to quantum computation and communication, we consider state transfer in the simplest non-trivial system of four particles representing exchange-coupled qubits.

Dinamica della torsione elettrogravitazionale e ingegneria dello spaziotempo: Un approccio unificato Einstein-Cartan-BRST utilizzando Spin-OAM This paper presents a theoretical and experimental study of the role of the axial torsion of the Cartan tensor in spacetime, treated as a massive Proca-type vector field coupled to the angular momentum of matter and radiation. The goal is to propose an effective framework (EFT) that describes these interactions and to outline an experimental setup capable of detecting torsional effects produced by electromagnetic fields with orbital angular momentum (OAM). 1. Introduction The Einstein-Cartan theory of gravity extends General Relativity by including torsion as a spin-related degree of freedom. The axial component of torsion interacts with spin fields and can be treated as a dynamically propagating massive field. The study aims to: Formalize an effective action with a mass term and non-minimal couplings. Predict measurable effects in laboratory experiments. Provide protocols for their detection. 2. Theoretical Framework 2.1 Effective Action The action includes: Proca-type kinetic term for the torsional field. Mass term. Direct couplings with spin currents and orbital angular momentum. Possible non-minimal operators with constants. 2.2 Field Equations The equations of motion derive from: \partial_\nu H^{\nu\mu} + m_S^2 S^\mu = g_s J^\mu_5 + g_o L^\mu Wave propagation is expected with Compton length. 2.3 Orders of Magnitude Estimation Numerical example: GHz Source power kW Orbital angular momentum Torsional mass eV The resulting field is very small but potentially measurable. 3. Experimental Strategies 3.1 General Concept The experiment involves generating a torsional field using OAM-structured electromagnetic radiation and observing its interactions with sensitive devices. The system is designed to: Maximize angular momentum density. Reduce noise and spurious electromagnetic interactions. Enable reproducibility and falsifiability. 3.2 Apparatus OAM Generator: Logarithmic spiral antennas, metasurfaces, waveguides, or phased antenna arrays. Detectors: Interferometers, mechanical resonators, optical torsometers, or weak-force resonant cavities. Control: Systems for managing polarization, phase modulation, and time synchronization. 4. Measurement and Analysis Protocols 4.1 Interferometric Measurement We seek a phase delay proportional to the torsional potential integrated along the optical path. \Delta t = \int S_0 \, dl / c 4.2 Measurement of Forces or Torques A torsional torque induced on a suspended body or a resonant cavity is measured. The amplitude is proportional to the product of the torque and the total angular momentum of the incident field. 4.3 Falsification Strategies Comparison with zero-OAM experiments. Polarization, power, and frequency control. Rotation of the configuration and blind measurements. Use of materials with controlled magnetic response. 5. Simulations and Modeling Numerical methods are suggested for predicting the behavior of the torsional field: FDTD (Finite-Difference Time-Domain) for EM propagation. FEM (Finite Element Method) for field distribution in cavities and structures. Thermal analysis to minimize spurious effects. 6. Potential Applications Although speculative, the paper hypothesizes future applications: Torsion-based propulsion: interaction between OAM and the torsional field as a momentum transfer mechanism. Gravitational metamaterials: structures that exploit torsional effects to manipulate local properties of space-time. Astrophysical detection: possibility of observing torsional signals in cosmic environments with high spin density. 7. Conclusions The paper proposes a systematic approach to treat axial torsion as an effective physical field, formulating a coherent theoretical model and outlining concrete experiments for its detection. The research opens up prospects for verifying previously unexplored gravitational phenomena and for developing new technologies based on the interaction between torsion and structured radiation. Appendices (technical sections) Appendix A: Derivations of the field equations and relations with gauge theories. Appendix B: Detailed formulas for the estimation of and . Appendix C: Guidelines for Numerical Simulations and Input Parameters. 📌 In Summary The paper combines an advanced theoretical framework for gravity with torsion and an experimental plan for its laboratory verification, exploiting electromagnetic fields with orbital angular momentum. The torsion field is treated as a massive vector field coupled to the spin and angular momentum of radiation, proposing strategies for its detection through interferometry, torsional measurements, and numerical simulations. Finally, long-term technological and astrophysical implications are explored.

Lectures from the National Programme on Technology Enhanced Learning - Chemical Engineering - Computational Fluid Dynamics

Lectures from the National Programme on Technology Enhanced Learning - Chemical Engineering - Computational Fluid Dynamics

Soil Dynamics and Earthquake Engineering 2005: Volume 25 , Issue INDEX/CONTENTS. Digitized from IA1652804-02 . Previous issue: sim_soil-dynamics-and-earthquake-engineering_2004-12_24_12 . Next issue: sim_soil-dynamics-and-earthquake-engineering_2005-01_25_1 .

Soil Dynamics and Earthquake Engineering 2005: Volume 25 , Issue INDEX/CONTENTS. Digitized from IA1652804-02 . Previous issue: sim_soil-dynamics-and-earthquake-engineering_2004-12_24_12 . Next issue: sim_soil-dynamics-and-earthquake-engineering_2005-01_25_1 .

Computational fluid dynamics (CFD) and other advanced modeling and simulation (M&S) methods are increasingly relied on for predictive performance, reliability and safety of engineering systems. Analysts, designers, decision makers, and project managers, who must depend on simulation, need practical techniques and methods for assessing simulation credibility. The AIAA Guide for Verification and Validation of Computational Fluid Dynamics Simulations (AIAA G-077-1998 (2002)), originally published in 1998, was the first engineering standards document available to the engineering community for verification and validation (V&V) of simulations. Much progress has been made in these areas since 1998. The AIAA Committee on Standards for CFD is currently updating this Guide to incorporate in it the important developments that have taken place in V&V concepts, methods, and practices, particularly with regard to the broader context of predictive capability and uncertainty quantification (UQ) methods and approaches. This paper will provide an overview of the changes and extensions currently underway to update the AIAA Guide. Specifically, a framework for predictive capability will be described for incorporating a wide range of error and uncertainty sources identified during the modeling, verification, and validation processes, with the goal of estimating the total prediction uncertainty of the simulation. The Guide's goal is to provide a foundation for understanding and addressing major issues and concepts in predictive CFD. However, this Guide will not recommend specific approaches in these areas as the field is rapidly evolving. It is hoped that the guidelines provided in this paper, and explained in more detail in the Guide, will aid in the research, development, and use of CFD in engineering decision-making.

Aviation Technology Directorate's Digitial IntegratedTechnology Team Aircraft Lifecycle Innovation Hub Research Scientist Andrea Sansica on the Future of Aircraft Manufacturing, Digital Twins, Machine Learning, Engineering Research Papers, Japanese Food, Making Music, Wind Tunnels, and Fluid Dynamics. Sparse Identification of Nonlinear Dynamical systems (SINDy) Download for Python - https://github.com/dynamicslab/pysindy Dr. Steve Brunton's YouTube Channel - https://www.youtube.com/c/Eigensteve

Advanced Engineering Dynamics Harrison & Nettleton

THE FLIGHT DYNAMICS LABORATORY (FDL) IS ONE OF THE WORLD'S MOST ADVANCED AIRCRAFT TECHNOLOGY DEVELOPMENT FACILITIES. THIS REPORT EXAMINES THE PAST, PRESENT AND FUTURE OF THE FLIGHT DYNAMICS LABORATORY ACCORDING TO FIVE BROAD TECHNOLOGICAL AREAS: FLIGHT CONTROL, VEHICLE EQUIPMENT OR SUBSYSTEMS, AEROMECHANICS, STRUCTURES, AND DYNAMICS. ADVANCED DEVELOPMENT PROGRAMS CLOSELY IDENTIFIED WITH A PARTICULAR DIVISION ARE INCLUDED IN THE APPROPRIATE CHAPTER, WHILE OPERATIONAL AND TECHNICAL SUPPORT ARE COVERED IN A SEPARATE SECTION.

It has been shown that optimal controller synthesis for positive systems can be formulated as a linear program. Leveraging these results, we propose a scalable iterative algorithm for the systematic design of sparse, small gain feedback strategies that stabilize the evolutionary dynamics of a generic disease model. We achieve the desired feedback structure by augmenting the optimization problems with l1 and l2 regularization terms, and illustrate our method on an example inspired by an experimental study aimed at finding appropriate HIV neutralizing antibody therapy combinations in the presence of escape mutants.

View the complete course: http://ocw.mit.edu/2-003SCF11 Instructor: J. Kim Vandiver This course covers the basics of engineering dynamics. After this course, students will be able to evaluate free and forced vibration of linear multi-degree of freedom models of mechanical systems and matrix eigenvalue problems. License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu

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From case: Professional Engineering Development  (Civil Engineering Development 402, U.S. Air Force Academy) vols.300 & 301: Statics And Dynamics, parts 3 & 4 TA 155 P7 v.300 28301

From case: Professional Engineering Development  (Civil Engineering Development 402, U.S. Air Force Academy) vols.300 & 301: Statics And Dynamics, parts 3 & 4 TA 155 P7 v.300 28301

From case: Professional Engineering Development  (Civil Engineering Development 402, U.S. Air Force Academy) vols.300 & 301: Statics And Dynamics, parts 3 & 4 TA 155 P7 v.300 28301

From case: Professional Engineering Development  (Civil Engineering Development 402, U.S. Air Force Academy) vols.300 & 301: Statics And Dynamics, parts 3 & 4 TA 155 P7 v.300 28301

Measures of wealth and production have been found to scale superlinearly with the population of a city. Therefore, it makes economic sense for humans to congregate together in dense settlements. A recent model of population dynamics showed that population growth can become superexponential due to the superlinear scaling of production with population in a city. Here, we generalize this population dynamics model and demonstrate the existence of multiple stable equilibrium points, showing how population growth can be stymied by a poor economic environment. This occurs when the goods and services produced by the city become less profitable due to a lack of diversification in the city's economy. Then, relying on critical slowing down signals related to the stability of an equilibrium point, we present an algorithm for engineering regime shifts such that a city at a stable equilibrium point may continue to grow again. The generality of the model and the algorithm used here implies that the model and algorithm need not be restricted to urban systems; they are easily applicable to other types of systems where the assumptions used are valid.

We analyze the asymptotic behavior of discrete-time, Markovian quantum systems with respect to a subspace of interest. Global asymptotic stability of subspaces is relevant to quantum information processing, in particular for initializing the system in pure states or subspace codes. We provide a linear-algebraic characterization of the dynamical properties leading to invariance and attractivity of a given quantum subspace. We then construct a design algorithm for discrete-time feedback control that allows to stabilize a target subspace, proving that if the control problem is feasible, then the algorithm returns an effective control choice. In order to prove this result, a canonical QR matrix decomposition is derived, and also used to establish the control scheme potential for the simulation of open-system dynamics.

The objective of the Reactor Dynamics Module, RD-1, is to obtain the kinetics equation without feedback and solve the kinetics equations numerically for one to six delayed neutron groups for time varying reactivity insertions. The computer code FUMOKI (Fundamental Mode Kinetics) will calculate the power as a function of time for either uranium or plutonium. Either fuel can be used with one to six delayed neutron groups and one of three types of reactivity insertions: a constant reactivity, sinusoidal, or a ramp. The code does not compute any parameters so the neutron generation time must be provided. The user has the option of studying the effects of various time steps in solving the system. The objective of Module RD-2 is to examine the temperature feedback mechanism of a pressurized water reactor (PWR) and solve the one delayed neutron model with temperature feedback for a step insertion and a ramp insertion of reactivity. A PWR core with a two-path feedback is considered. The core region is the only one of interest in this module. The program name is FUMOTEM (Fundamental Mode Kinetics with Temperature Feedback). There are four types of reactivity inputs that the program can accommodate. (Author)

We develop a scheme to prepare a desired state or subspace in high-dimensional Hilbert-spaces using repeated applications of a single static projection operator onto the desired target and fixed unitary dynamics. Benchmarks against other control schemes, performed on generic Hamiltonians and on Bose-Hubbard systems, establish the competitiveness of the method. As a concrete application of the control of mesoscopic atomic samples in optical lattices we demonstrate the near deterministic preparation of Schr\"{o}dinger cat states of all atoms residing on either the odd or the even sites.

Going beyond the currently investigated regimes in experiments on quantum transport of ultracold atoms in disordered potentials, we predict a crossover between regular and quantum-chaotic dynamics when varying the strength of disorder. Our spectral approach is based on the Bose-Hubbard model describing interacting atoms in deep random potentials. The predicted crossover from localized to diffusive dynamics depends on the simultaneous presence of interactions and disorder, and can be verified in the laboratory by monitoring the evolution of typical experimental initial states.

Going beyond the currently investigated regimes in experiments on quantum transport of ultracold atoms in disordered potentials, we predict a crossover between regular and quantum-chaotic dynamics when varying the strength of disorder. Our spectral approach is based on the Bose-Hubbard model describing interacting atoms in deep random potentials. The predicted crossover from localized to diffusive dynamics depends on the simultaneous presence of interactions and disorder, and can be verified in the laboratory by monitoring the evolution of typical experimental initial states.

Bibliography: p. 43-44

Bibliography: p. 43-44

Bibliography: p. 43-44