Strain adjustments associated with earthquakes in southern California

A technique for the calculation of strain changes in a two-dimensional elastic body with arbitrary internal dislocations is presented. This technique is applied to the southern California region by assigning a specific fault and fault slip function for each major earthquake that has occurred since 1812. Although the model used has serious shortcomings when applied to the real Earth, certain important features concerning strain energy changes associated with earthquakes are brought out. The occurrence of earthquakes over the past 150 years has resulted in net increases in stored strain energy in a number of regions including the northern end of the Gulf of California, the Cajon Pass area, and the northern part of the Carizzo Plain. Large regions of strain energy decrease can also be seen, the most important of which is in the vicinity of Fort Tejon

From theory to practice of transition management: The case of Sustainable Living and Housing in Flanders

Our modern complex society and its problems of realizing long-term sustainable development necessitate new forms of governance. In recent years a number of publications have been made on transition management as a new mode of governance that explicitly deals with societal complexity (D. Loorbach, 2007; J. Rotmans, Grin, Schot, & Smits, 2004; J. Rotmans, Kemp, & Van Asselt, 2001). This approach towards dealing with governance and complexity explicitly links analysis of complexity to the governance hereof. Observed dynamics in society provide the basis for formulating governance strategies and instruments, while the implementation of transition management simultaneously leads to more precise or altered interpretations of observed reality. Transition management as formulated in (D. Loorbach, 2007) presents a framework for structuring governance processes directed towards societal innovation. This framework distinguishes between different types of activities (strategic, tactical and operational) and different phases (envisioning, agenda-building, experimentation and evaluation). The basic assumption is that this framework is generic and can be used to implement transition management within any specific context (being a specific policy domain or political culture). The proposed paper aims to illustrate how the framework can be used to implement transition management and under which conditions such an implementation of transition management can be successful. This will be done by analyzing the project ‘Sustainable Living and Housing in Flanders’, in which the two authors functioned as project leaders

Revealing Bluff-Body Aerodynamics on Low-Rise Buildings under Tornadic Winds using Numerical Laboratory Tornado Simulator

Tornadoes result in death and property loss in communities around the world. To quantify the actions of tornadoes on civil structures, researchers have built physical laboratory tornado simulators to simulate tornadoes in the lab environment and tested building models in the simulated tornadic wind field, which is similar to wind tunnel testing when quantifying the wind effects induced by straight-line winds. Unfortunately, physical tornado simulators are much less common than straight-line wind tunnels, leading to the lack of research on bluff-body aerodynamics on civil structures under tornadic winds. Considering that it is expensive to conduct experimental testing in physical tornado simulators, numerical models of physical tornado simulator has been developed using computational fluid dynamics (CFD) simulations. However, they have not been validated at the level of pressure distribution on the structural surface of the testing model. In this study, the numerical model developed for the large-scale tornado simulator of the Missouri University of Science and Technology (Missouri S&T), which is based on the numerical simulation of the entire process of the physical testing in tornado simulator, will be validated by the measured data on the building model tested in the physical tornado simulator. Then, through the validated numerical simulation model, the bluff-body aerodynamics of buildings under tornadic winds will be revealed. To be specific, CFD simulation is first applied to model the entire process of experimental testing of a low-rise building model in the physical tornado simulator. Then, the obtained results are compared with laboratory-measured data to evaluate the effects of the building model on the wind field and the surface pressure on the building model. Then, the bluff-body aerodynamics on low-rise buildings under tornadic winds will be revealed based on the data obtained from numerical simulations using the relationship between streamline pattern change and velocity magnitude change (mass continuity theorem) and using the relationship between the velocity magnitude change and the pressure change (Bernoulli\u27s theorem), as well as the flow separation and vortex shedding

Economic Analysis of the Potential for Nuclear Energy Investment in Eastern Europe

This paper contributes to the ongoing discussion on the impacts of nuclear energy on the economy and energy security of select European countries. While previous literature has identified a connection between nuclear energy and economic growth, this study focuses on assessing the comparative effects of nuclear energy, measured by operable nuclear power capacity (MWe), on energy self-sufficiency across a range of European countries. By employing a two-way fixed effects model, this study analyzes the potential relationship between nuclear energy capacity and energy self-sufficiency while accounting for various factors that influence both variables. To ensure the robustness of findings, collinearity was examined using the variance inflation factor (VIF), which gauges the presence of multicollinearity among independent variables. Additionally, stationarity was investigated through unit root tests (ADF test) to assess the long-term behavior of the variables under inspection. This analysis reveals compelling results, suggesting that investment in nuclear energy has the potential to enhance energy self-sufficiency for multiple European countries, with a particular emphasis on certain Eastern European nations. By exploring the specific effects of nuclear energy capacity on energy self-sufficiency, this study provides valuable insights for policymakers, private nuclear companies, and researchers interested in the sustainable development of advanced nuclear energy systems in Europe.Keywords: Nuclear Energy, Econometrics, Economic Analysis, Energy Economic

Modeling the Fusion Reaction in an Inertial Electrostatic Confinement Reactor with the Particle-in-Cell Method

Nuclear fusion has the potential to meet the energy needs of our civilization for centuries to come and does not produce harmful greenhouse gasses or produce long-lasting radioactive waste. A fusion reaction can be readily demonstrated in a confinement scheme known as inertial electrostatic confinement (IEC) fusion. In this work, an IEC device is proposed that can perform a study of how the fusion rate in an IEC depends on cathode voltage. A 2D simulation code is written in python to model the device and predict the fusion response to grid voltage at low and high voltages. The simulation is based on the particle-in-cell (PIC) method for modeling plasmas. The fusion reaction was modeled in the simulation by applying the 5-parameter-fitting method for nuclear fusion cross sections. A formula for the probability of a fusion reaction occurring per simulated particle path length is proposed based on physical and numerical parameters. The simulation demonstrates that as the cathode grid voltage is increased, the fusion rate occurring in the device increases in the same manner as key IEC experiments. The seldom-studied start-up behavior of the IEC was resolved in the simulation implemented here and presented for different cathode voltages

Minimum Performance Targets for the Built Environment based on Community-Resilience Objectives

Disrupted critical infrastructure systems following disasters can result in population outmigration which may subsequently negatively impact a communitys indirect socioeconomic losses over time. In this study, a community was modeled with its interconnected physical-socio-economic attributes and population outmigration was used as a basic proxy community resilience metric. The probability of outmigration for each household was assessed based on the probability that the school-age students, household residents, and employees in the household are affected over a prescribed time period from the occurrence of the hazard to the full restoration of the community. Finally, the potential population outmigration for the community was assessed by aggregating the probability for all the households in the community. Additionally, a prediction model for the number of injuries and fatalities was implemented in the analysis to be served as a community-level life-safety metric. Ultimately, these metrics were combined and utilized to propose a framework for disaggregation of a set of community-level objectives into a set of performance targets for the components of the built environment. Such a model is desirable for policymakers and community leaders in order to make long-term decisions for their community

Seismic Performance Comparison of a High-Content SDA Frame and Standard RC Frame

This study presents the method and results of an experiment to study the seismic behavior of a concrete portal frame with fifty percent of its cement content replaced with a spray dryer ash (SDA). Based on multiple-shake-table tests, the high content SDA frame was found to perform as well as the standard concrete frame for two earthquakes exceeding design-level intensity earthquakes. Hence, from a purely seismic/structural standpoint, it may be possible to replace approximately fifty percent of cement in a concrete mix with SDA for the construction of structural members in high seismic zones. This would help significantly redirect spray dryer ash away from landfills, thus, providing a sustainable greener alternative to concrete that uses only Portland cement, or only a small percentage of SDA or fly ash

Development of empirically-based fragilities of residential damage in the 2011 Joplin, Missouri tornado

Performance-based engineering (PBE) is a methodology that requires specification on a range of performances or target reliabilities for structures of different importance. Information on these ‘performance levels’ require a probabilistic assessment of the potential factors that may influence a design, including information on the hazard, load, resistance, loss estimates, expert opinion and public perception. This paper describes one such probabilistic assessment in the development of empirically-based fragility functions for tornadoes using damage assessment data and a tornado wind field model for the 22 May 2011 Joplin, MO tornado. The damage assessment data was collected during field surveys of more than 1,240 structures in the aftermath of the tornado, using provisions of the Enhanced Fujita (EF) Scale to assess the damage. The wind field model was developed from the tree-fall patterns noted in the damage path of the tornado. Fragility functions were developed for the Degrees of Damage (DOD) associated with One- and Two-Family Residences in the EF Scale. The empiricallyderived fragility functions were progressive in nature, with median wind speeds varying from 33.6 m/s for initiation of visible damage to 85.2 m/s for complete destruction. These functions were compared to existing fragility functions for straightline winds to evaluate potential differences in failure mechanisms for structures exposed to tornadoes. Wind speeds associated with the median failure probability were used to estimate load factors, defined as the square of the ratio of the straightline wind speed to the tornado wind speed. Structures tended to fail at lower wind speeds in tornadoes than in straightline winds, with load factors between 1.32 and 1.51. A fragility assessment in the context of PBE naturally requires attribution and quantification of all uncertainties. Uncertainties in the both the damage and wind speed estimation in the development of fragilities are quantified and assessed using Monte Carlo methods. Preliminary results show variance in fragility parameters is higher for higher damage states but all damage states have relatively low coefficients of variation