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The ability to obtain complex global behaviour from simple local rules makes cellular automata an interesting platform for massively parallel computation. However, manually designing a cellular automaton to perform a given computation can be extremely difficult, and automated design techniques such as genetic programming have their limitations because of the absence of human intuition. In this paper, we propose elements of a framework whose goal is to make the manual synthesis of cellular automata rules exhibiting desired global characteristics more programmer-friendly, while maintaining the simplicity of local processing elements. Although many of the framework elements that we describe here are not new, we group them into a consistent framework and show that they can all be implemented on a traditional cellular automaton, which means that they are merely more human-friendly ways of describing simple cellular automata rules, and not foreign structures that require changing the traditional cellular automaton model.

An approximate explicit method from literature to estimate the corrosion initiation time of steel reinforcement in concrete is developed to incorporate random variables which affect the diffusion rate. The method accounts for uncertainties of input parameters and predicate expected time of first corrosion for the chosen risk of corrosion and its variance. Method is also utilized to rank the sensitive parameters to initiate steel reinforcement corrosion. Corrosion is initiated when the chloride concentration on steel reinforcement exceeds a threshold value. Corrosion initiation time is useful for owner, designer, or to an organization to take decision in time of priority of repairs, repair strategy, corrosion protection in order to optimize maintenance planning and budgeting. Planned maintenance at the optimum time is the safest and most cost effective approach.

Corrosion initiation time of steel reinforcement for partially saturated concrete members subjected to chloride ingress is investigated at five places along Indian coasts using simplified probabilistic analysis and sensitivity of the parameters to reinforcement corrosion is studied. Previously proposed diffusion based chloride ingress model for constant surface chloride concentration and variable diffusion coefficient is used. Corrosion is initiated when the chloride concentration on steel reinforcement exceeds a threshold value. The various input parameters considered in the model are surface chloride concentration (C_s), chloride threshold value (C_th), Concrete cover (X), reference diffusion coefficient (D_ref), age (t), reference age (t_ref), diffusion decay index (m) and monthly temperature and relative humidity correction factors f(T) and f(h) respectively; to reference diffusion coefficient. For prediction of corrosion initiation time temperature and relative humidity data collected by India metrological Department is used and all other parameters are assumed same. A large variation in corrosion initiation time is found and therefore it becomes necessary to consider the temperature and relative humidity data in a region. Life-365 considers fully saturated condition of concrete and thus underestimates the corrosion initiation time of a reinforced concrete member. The deterministic approach uses mean values of the parameters and provides a 50% probability of corrosion initiation but the probabilistic approach provides expected time of first corrosion for chosen risk of corrosion and also gives sensitivity of parameters to probability of corrosion. Corrosion initiation time in ascending order is found at Colaba, Kanyakumari, Santacruz, Chennai and Vishakhapatnam. Corrosion initiation time is useful for owner, designer, or to an organization to take decision in time of priority of repairs, repair strategy, corrosion protection in order to optimize maintenance planning and budgeting. Planned maintenance at the optimum time is the safest and most cost effective approach.

Labelling line drawings is a useful technique in several applications, including that of automated interpretation of line drawings as polyhedral solid objects. Algorithms exist which can in practice label line drawings of trihedral polyhedra correctly in low-order polynomial time. However, the restriction to trihedral polyhedra is too limiting for practical applications.

We are primarily interested in interpreting line drawings of engineering objects, and many of these objects contain non-trihedral (usually tetrahedral) vertices. We therefore investigate two alternative algorithms for labeliing drawings of such objects, one deterministic and the other probabilistic. We find that our deterministic solution achieves better results in terms of correctness but can be unacceptably slow, and that our probabilistic solution, while acceptably quick, is less successful in terms of correctness.

The discrepancy between the analytically determined buckling load of perfect cylindrical shells and experimental test results is traced back to imperfections. The most frequently used guideline for design of cylindrical shells, NASA SP-8007, proposes a deterministic calculation of a knockdown factor with respect to the ratio of radius and wall thickness, which turned out to be very conservative in numerous cases and which is not intended for composite shells. In order to determine a lower bound for the buckling load of an arbitrary type of shell, probabilistic design methods have been developed. Measured imperfection patterns are described using double Fourier series, whereas the Fourier coefficients characterize the scattering of geometry. In this paper, probabilistic analyses of buckling loads are performed regarding Fourier coefficients as random variables. A nonlinear finite element model is used to determine buckling loads, and Monte Carlo simulations are executed. The probabilistic approach is used for a set of six similarly manufactured composite shells. The results indicate that not only geometric but also nontraditional imperfections like loading imperfections have to be considered for obtaining a reliable lower limit of the buckling load. Finally, further Monte Carlo simulations are executed including traditional as well as loading imperfections, and lower bounds of buckling loads are obtained, which are less conservative than NASA SP-8007.

We experimentally demonstrate a protocol of probabilistic remote state preparation by virtue of entanglement, local operation and forward classical communications. Arbitrary polarization qubit state can be remotely prepared with this protocol. For both pure states and mixed states, the average efficiency is no less than 50% and the classical information cost is 1 bit. All 18 remotely prepared states were estimated with quantum state tomography system. The fidelities are all above 0.99, with average fidelity being 0.9956.

Different time-dependent mechanisms such as creep, environmental surface oxidation or internal material degradation due to aging and irradiation will subject structures to the possibility of premature failures. In this paper a micro-scale finite element mesh consisting of multiple elements encased in ~50–150μm sized grains with designated grain boundaries is used to replicate shapes and dimensions to simulate an isotropic metallic microstructure. The grains are encased in pseudo-grain boundary element sets which can have different material and damage parameters compared to the grains. In this type of mesh random crack paths for intergranular and transgranular cracking conditions are allowed. It is shown that creep cracking using a uniaxial ductility constraint-based model coupled with a functionally distributed time-dependent environmentally assisted corrosion/oxidation/material degradation damage model acting on surface or internally can be realistically predicted using this model. It is also evident material properties input data have scatter especially at the sub-grain level where the measurement methods are new and not always standardised. This is dealt with in the model by employing a normal distributive probabilistic method to allow for statistically varied random damage and crack growth development. In this way it is possible to take into account the inherent variability in material input properties at the analysis stage without the need to change material properties following each run. The method could negate the need for knowing the exact material properties, which in any case is impossible to derive at the microstructural level, as results of each run can be varied using a statistically distributed critical damage criterion specified for each element.

In this study, the seismic hazards of Myanmar are analyzed based on both deterministic and probabilistic scenarios. The area of the Sumatra–Andaman Subduction Zone is newly defined and the lines of faults proposed previously are grouped into nine earthquake sources that might affect the Myanmar region. The earthquake parameters required for the seismic hazard analysis (SHA) were determined from seismicity data including paleoseismological information. Using previously determined suitable attenuation models, SHA maps were developed. For the deterministic SHA, the earthquake hazard in Myanmar varies between 0.1 g in the Eastern part up to 0.45 g along the Western part (Arakan Yoma Thrust Range). Moreover, probabilistic SHA revealed that for a 2% probability of exceedance in 50 and 100 years, the levels of ground shaking along the remote area of the Arakan Yoma Thrust Range are 0.35 and 0.45 g, respectively. Meanwhile, the main cities of Myanmar located nearby the Sagaing Fault Zone, such as Mandalay, Yangon, and Naypyidaw, may be subjected to peak horizontal ground acceleration levels of around 0.25 g.

Probabilistic seismic hazard analysis (PSHA) has become a fundamental tool in assessing seismic hazards and for estimating seismic design and seismic safety evaluation of ground motions. This report describes a study to test and verify the numerical approaches and software used in PSHA on Semnan, one of the important cities of Iran country. The geological and seismological data are integrated into a probabilistic seismic hazard model for the region. Historical and instrumental earthquake data, geology, tectonics, fault activity, and seismic source models associated with seismic events are taken into account. A probabilistic approach within a logic-tree framework is used to calculate seismic hazard for Semnan. The results were also displayed in terms of uniform hazard spectra for rock sites for return periods of 100, 475 and 2475 years, which is deemed appropriate for structural design standards in the Iran building code. As the results of this study have been displayed on the map for different return periods and different natural periods, it can provide the basis for the preparation of new seismic risk maps.

Earthquakes in the Mid-America region are low probability-large consequence events. The purpose of this study is to develop a methodology for probabilistic performance evaluation of existing and retrofitted essential facilities (EF) such as fire stations and police stations under earthquake excitation in Mid-America. Since most essential facilities in the Mid-America region have not been designed for seismic forces, the vulnerability of such structures is a serious concern. Only un-reinforced masonry (URM) buildings, which represent most EFs in mid-America, are considered in this study. A finite element model based on ABAQUS was developed. Structural components such as walls and diaphragms in masonry buildings usually go into inelastic state under severe earthquakes and the inelastic restoring forces of the walls are dependent on the loading history. To model these response behaviors, a nonlinear force-displacement model is developed. Four wall damage models, diagonal tension, bed-joint sliding, toe crushing, and rocking are considered. The wall drift ratio is used as a measure of the overall response and damage to nonstructural components and contents such as equipments. Results show that retrofitting is needed for all buildings for satisfactory performance according to most recent code recommendations. For retrofit, the center core method is considered here. The method embeds the reinforcing bars within an existing un-reinforced masonry wall. The results show that this method only enhances the building performance moderately; other more efficient retrofit methods may be necessary.

Indonesia has been well known as one of the most seismically active countries in the world. It is surrounded by three major active tectonic plates of the earth: Eurasian, Indo-Australian, and Philippine plates. The most effective way to reduce disasters caused by earthquakes is to estimate the seismic hazard and to implement this information on a seismic code for use in infrastructure design and construction so that the infrastructures possess adequate earthquake resistant capacity.

Several great earthquake occurrences in Indonesia in the last six years inquire revision of seismic hazard parameters. The need to revise current Indonesian Seismic Hazard Map expressed as PGA contained in our latest Indonesian Earthquake Resistant Building Code SNI 03-1726-2002 was driven among others by the desire to better reflect potential larger earthquake disasters faced by the nation predictably in the future. Two major expected revisions are the earthquake hazard map, to reflect the latest advancement in Seismic Hazard Analysis technology accounting for potential larger disasters predicted in the near future, and changing the provision from UBC-97 concept to the latest IBC-2009 and ASCE 7-2010 provisions. The Department of Public Works then established Team for Revision of Seismic Hazard Maps of Indonesia 2010. This team has worked to develope probabilistic, deterministic, Maximum Considered Earthquake (MCE), and Risk-targeted Maximu Considered Earthquake (MCE_R) maps of Indonesia. The maps were developed based on probabilistic and deterministic approaches by using three-dimensional seismic source models and by considering latest geological and seismological data and fragility curves of buildings.

The works were performed using this following procedure: 1) conducting literature review on geology, geophysics and seismology to identify activity of seismic sources in and around Indonesian region, 2) collecting and processing recorded earthquake data for entire Indonesian region, 3) modeling seismic source zones based on the advance models appropriate with USGS software, 4) determining seismic parameters which include a-b values, maximum magnitudes, and slip-rates, 5) calculating spectral acceleration based on probabilistic and deterministic theorems, 6) mapping MCE and MCE_R.

Seismic parameters used in this study were derived from published journals, proceedings, previous researches conducted by team members, and latest information obtained during this study. This study has then compiled and integrated previous and current studies. Earthquake source parameters were determined based on earthquake catalog, geological, and seismological information of active faults. The earthquake catalog covered earthquake period between 1900 to 2009, relocated catalog by the year 2005, and area between 90°E to 145°E longitudes and 15°S to 15°N latitudes.

Seismic sources were devided into subduction, fault, and background zones by considering recurrence relationship that includes truncated exponential model, pure characteristic model, and both models. Geometry of fault and subduction were represented by three-dimensional (3D) models based on the result of tomography and slip-rates of faults were determined by considering the results of GPS measurement. Background source zones were modeled using gridded seismicity based on spatially smoothed earthquake rates. The earthquake catalog was used for developing gridded seismicity starting from 1900 to 2009 and the updated Engdahl catalog up to 2009 was used for control geometry of subduction. Several well-known attenuation functions were selected in accordance with the mechanism of seismic source including the Next Generation Attenuation (NGA). Logic tree was also applied to account for epistemic uncertainty including recurrence model, maximum magnitude, and several attenuation functions.

The hazard levels were calculated to represent probabilistic of peak ground acceleration (PGA) and spectral acceleration for short periods (0.2 seconds) and the period of 1 second with 10% probability of exceedance (PE) in 50 years (475-year earthquake), 10% in 100 years (950-year earthquake), 2% in 50 years (2475-year earthquake), 50 and 200-year earthquake and deterministic for 84% percentile (150% median). These sesimic hazard maps will be use for the design of earthquake resistance infrastructures in Indonesia in the coming codes and standards. For building design, it has been decided that ASCE 7-2010 will be adopted for the coming code that use MCE_R map intergrating deterministis, probabilistic 2500-year earhtquake, and fragility curves of buildings.

In general, the results of this study are higher than those of current Indonesian Seismic Hazard Map in Indonesian Earthquake Resistant Building Code SNI 03-1726-2002, especially for locations near active fault. The increase of PGA values is affected by the increase of maximum magnitudes, new identification of fault and other input parameters and by utilizing a 3D earthquake source model.

For improvement of seismic design of infrastructures in Indonesia in the future, the team has also proposed the following recommendations; 1. Conducting microseismic investigation for unidentified/unquantified faults, 2. Accelerating the installation of strong-motion accelerometer networks in Indonesia in order to develope database of time histories and to develop attenuation functions of Indonesia, 3. Conducting microzonation studies for big cities in Indonesia, and 4. Conducting periodic updating maps every 3-5 years.

Note from Publisher: This article contains the abstract only.