Narrow Results

An efficient simulation algorithm using an algebra of transients for gate circuits was proposed by Brzozowski and Ésik. This algorithm seems capable of predicting all the signal changes that can occur in a circuit under worst-case delay conditions. We verify this claim by comparing simulation with binary analysis. For any feedback-free circuit consisting of one- and two-input gates, we prove that all signal changes predicted by simulation occur in binary analysis, provided that wire delays are taken into account. Two types of finite automata play an important role in our proof.

Transient simulation of a gate circuit is an efficient method of counting signal changes occurring during a transition of the circuit. It is known that this simulation covers the results of classical binary analysis, in the sense that all signal changes appearing in binary analysis are also predicted by the simulation. For feedback-free circuits of 1- and 2-input gates, it had been shown that the converse also holds, if wire delays are taken into account. In this paper we generalize this result. First, we prove that, for any feedback-free circuit N of arbitrary gates, there exists an expanded circuit, constructed by adding a number of delays to each wire of N, such that binary analysis of covers transient simulation of N. For this result, the number of delays added to a wire is obtained from the transient simulation. Our second result involves adding only one delay per wire, which leads to the singular circuit of N. This result is restricted to circuits consisting only of gates realizing functions from the set , functions obtained by complementing any number of inputs and/or the output of a function from , and FORKS. The numbers of inputs of the AND, OR and XOR gates are arbitrary, and all functions of two variables are included. We show that binary analysis of such a circuit covers transient simulation of N. We also show that this result cannot be extended to arbitrary gates, if we allow only a constant number of delays per wire.

Transient algebra is a multi-valued algebra for hazard detection in gate circuits. Sequences of alternating 0's and 1's, called transients, represent signal values, and gates are modeled by extensions of boolean functions to transients. Formulas for computing the output transient of a gate from the input transients are known for NOT, AND, OR and XOR gates and their complements, but, in general, even the problem of deciding whether the length of the output transient exceeds a given bound is NP-complete. We propose a method of evaluating extensions of general boolean functions. We study a class of functions for which, instead of evaluating the extensions on a given set of transients, it is possible to get the same values by using transients derived from the given ones, but having length at most 3. We prove that all functions of three variables, as well as certain other functions, have this property, and can be efficiently evaluated.

The paper completes the cycle of the research devoted to the development of the experimental bifurcation analysis (not computer simulations) in order to answer the following questions: whether qualitative changes occur in the dynamics of local climate systems in a centennial timescale?; how to analyze such qualitative changes with daily resolution for local and regional space-scales?; how to establish one-to-one daily correspondence between the dynamics evolution and economic consequences for productions? To answer the questions, the unconventional conceptual model to describe the local climate dynamics was proposed and verified in the previous parts. That model (HDS-model) originates from the hysteresis regulator with double synchronization and has a variable structure due to competition between the amplitude quantization and the time quantization. The main advantage of the HDS-model is connected with the possibility to describe “internally” (on the basis of the self-regulation) the specific causal effects observed in the dynamics of local climate systems instead of “external” description of three states of the hysteresis behavior of climate systems (upper, lower and transient states). As a result, the evolution of the local climate dynamics is based on the bifurcation diagrams built by processing the data of meteorological observations, where the strange effects of the essential interannual daily variability of annual temperature variation are taken into account and explained. It opens the novel possibilities to analyze the local climate dynamics taking into account the observed resultant of all internal and external influences on each local climate system. In particular, the paper presents the viewpoint on how to estimate economic damages caused by climate-related hazards through the bifurcation analysis. That viewpoint includes the following ideas: practically each local climate system is characterized by its own time pattern of the natural qualitative changes in temperature dynamics over a century, so, any unified time window to determine the local climatic norms seems to be questionable; the temperature limits determined for climate-related technological hazards should be reasoned by the conditions of artificial human activity, but not by the climatic norms; the damages caused by such hazards can be approximately estimated in relation to the average annual profit of each production. Now, it becomes possible to estimate the minimal and maximal numbers of the specified hazards per year in order, first of all, to avoid unforeseen latent damages. Also, it becomes possible to make some useful relative estimation concerning damage and profit. We believe that the results presented in the cycle illustrate great practical competence of the current advances in the experimental bifurcation analysis. In particular, the developed QHS-analysis provides the novel prospects towards both how to adapt production to climatic changes and how to compensate negative technological impacts on environment.

The paper continues the application of the bifurcation analysis in the research on local climate dynamics based on processing the historically observed data on the daily average land surface air temperature. Since the analyzed data are from instrumental measurements, we are doing the experimental bifurcation analysis. In particular, we focus on the discussion where is the joint between the normal dynamics of local climate systems (norms) and situations with the potential to create damages (hazards)? We illustrate that, perhaps, the criteria for hazards (or violent and unfavorable weather factors) relate mainly to empirical considerations from human opinion, but not to the natural qualitative changes of climate dynamics. To build the bifurcation diagrams, we base on the unconventional conceptual model (HDS-model) which originates from the hysteresis regulator with double synchronization. The HDS-model is characterized by a variable structure with the competition between the amplitude quantization and the time quantization. Then the intermittency between three periodical processes is considered as the typical behavior of local climate systems instead of both chaos and quasi-periodicity in order to excuse the variety of local climate dynamics. From the known specific regularities of the HDS-model dynamics, we try to find a way to decompose the local behaviors into homogeneous units within the time sections with homogeneous dynamics. Here, we present the first results of such decomposition, where the quasi-homogeneous sections (QHS) are determined on the basis of the modified bifurcation diagrams, and the units are reconstructed within the limits connected with the problem of shape defects. Nevertheless, the proposed analysis of the local climate dynamics (QHS-analysis) allows to exhibit how the comparatively modest temperature differences between the mentioned units in an annual scale can step-by-step expand into the great temperature differences of the daily variability at a centennial scale. Then the norms and the hazards relate to the fundamentally different viewpoints, where the time sections of months and, especially, seasons distort the causal effects of natural dynamical processes. The specific circumstances to realize the qualitative changes of the local climate dynamics are summarized by the notion of a likely periodicity. That, in particular, allows to explain why $30$-year averaging remains the most common rule so far, but the decadal averaging begins to substitute that rule. We believe that the QHS-analysis can be considered as the joint between the norms and the hazards from a bifurcation analysis viewpoint, where the causal effects of the local climate dynamics are projected into the customary timescale only at the last step. We believe that the results could be interesting to develop the fields connected with climatic change and risk assessment.

Failure Mode and Effect Analysis (FMEA) has been used quite extensively in aerospace industry for several years to establish hardware criticality. Determination of software reliability is equally important. There are several methods for determining software reliability. One methods for performing software reliability is the software FMEA.

This paper discusses the application of principles to FMEA. A typical Tank pressurant is considered as an illustrative example. The tank pressurant system consists of three sets of solenoid valves (each set consists of a pair of valves), three pressure transducers, a vent valve, a heat exchanger and helium cold pressure bottles. Each set of solenoid valves consist of two solenoid valves connected in series. For the system to function properly, certain conditions have to be met. These are discussed in detail later in this paper.

Based on the information provided from NASA, it is concluded that FMEA has to be capable of determining the software failure modes, effects and criticality as well as the hardware failure modes effects and criticality which includes the pressure transducers, solenoid valves, vent valve, heat exchanger and helium cold pressure bottles. The paper will discuss both the hardware and software FMEA application in detail.

We surveyed disaster situations in the west coast of Thailand and the south coast of Sri Lanka where damage due to the Indian Ocean tsunami of December 2004 was severe, and investigated the destructive mechanism of structures due to the tsunami. The results we obtained were as follows:.

(1) If a tsunami with a ground-level inundation depth of more than two meters attacks a lowland extending several hundred meters or more inland, severe disaster will occur. In this case, mortar and brick buildings 30 cm or less in thickness will be destroyed.

(2) The stability of a building can be estimated using the easy stress calculating method by assuming a gatetype Rahmen building model and calculating dynamic water pressure.

(3) Destruction of revetments and seawalls is caused by incident wave pressure or return flow. In this case, the stability of a coastal structure is mainly determined by the balance of water pressure and earth pressure.

The evaluation of seismic risk of masonry monuments requires to study the combination of vulnerability and hazard. In the present work, the global seismic response of slender masonry towers has been studied by means of a specific 3-D fibre model. Accounting for the particular behaviour of such structures, the hazard should also be described by a suitable measure of intensity of the seismic action. A variety of different parameters relating with the ground acceleration recordings have been investigated for what regards their correlation with the damage indicators of the model. The combination of the peak ground velocity of the horizontal component and of the significant duration is an effective measure of intensity. This measure can be improved by considering the accord of the frequency content of the ground motion with the dynamical characteristics of the tower. Since in some cases the effect of the vertical component proved to be important, a further improvement can be obtained by taking into account also the vertical ground motion intensity.

Earthquake Early Warning Systems (EEWS), based on real-time prediction of ground motion or structural response measures, may play a role in reducing vulnerability and/or exposition of buildings and lifelines. In fact, recently seismologists developed efficient methods for rapid estimation of event features by means of limited information of the P-waves. Then, when an event is occurring, probabilistic distributions of magnitude and source-to-site distance are available and the prediction of the ground motion at the site, conditioned to the seismic network measures, may be performed in analogy with the Probabilistic Seismic Hazard Analysis (PSHA). Consequently the structural performance may be obtained by the Probabilistic Seismic Demand Analysis (PSDA), and used for real-time risk management purposes. However, such prediction is performed in very uncertain conditions which have to be taken into proper account to limit false and missed alarms. In the present study, real-time risk analysis for early warning purposes is discussed. The magnitude estimation is performed via the Bayesian approach, while the earthquake localization is based on the Voronoi cells. To test the procedure it was applied, by simulation, to the EEWS under development in the Campanian region (southern Italy). The results lead to the conclusion that the PSHA, conditioned to the EEWS, correctly predicts the hazard at the site and that the false/missed alarm probabilities may be controlled by set up of an appropriate decisional rule and alarm threshold.

This study aimed to explore emergency planning requirements for managing disasters in the Kingdom of Saudi Arabia (KSA). The study adopted interpretivism; an inductive approach; a descriptive survey; and qualitative methods to address its aim. The techniques used included a literature review and semi-structured interviews. The study sample consisted of 13 experts from the KSA General Directorate of Civil Defence (GDCD). The data were analyzed by using content analysis. The study findings revealed that the emergency planning requirements are administrative requirements, including regulations and legislation; technical requirements, which include equipment; human resources, including staff and responders; identifying, analyzing, and evaluating risks; determining the tasks and responsibilities of the relevant agencies and stakeholders; qualified leadership; determining the chain of command at national and local levels; coordination and cooperation among stakeholders; knowledge gained from local or international experiences; updated database; the availability of sufficient financial resources; completed infrastructure; and improved training and practice. The study also found that although emergency planning requirements are more or less in place, there is a need for further improvement and development; specifically, there is a need for better understanding, knowledge, and awareness. Consequently, it strongly recommends that all emergency planning requirements developed from this study should be implemented simultaneously and as an integrated whole. By doing so, it could help decision makers and emergency planners at government emergency agencies to improve, develop, and reinforce emergency planning, specifically in reducing disaster risks.

Coastal areas have become more exposed to natural hazards. Therefore, the management of coastal hazards is becoming more essential. Unfortunately, coastal hazards are often overlooked until their occurrence brings severe damage to the coastal areas. As more people develop their assets and properties in coastal areas, the impact from coastal hazard phenomena increases, such as the risk of potential hazards against coastal communities and properties as a result of sea level rise. The objectives of this paper are to evaluate and review the quality of the coastal hazard management plans that have been implemented in several countries. Developing advanced setbacks based on the need to avoid or reduce risk and accepting uncertainties can be established and translated into planning and management system in a pragmatic and effective way. An organization can learn from the success and failures, proving to be an effective approach that crosses functional boundaries. Best practices, new technologies and knowledge are to be transferred through this approach. The approach proposed in this study is the preparation of coastal hazard management for coastal communities through informed, coordinated and timely actions over long term. It is necessary to avoid an uncoordinated sectoral approach and locally incoherent mitigation countermeasures. From the lessons learned, it is important to follow appropriate and effective coastal hazard management cycle chart as a guidance for protecting the coastal area and the community.

In 2015 Hyogo Framework for Action (HFA) ends its term after ten years of implementation. International community is involved in the Post-HFA consultation process towards a new post-2015 framework for disaster risk reduction (DRR). Although HFA has proved to be effective in enhancing disaster risk reduction strategy in many fields, disaster risk is increasing. This chapter aims at evaluating how HFA has changed the way in which DRR is conceived and managed and what could be the prospective strategy for future decades. This chapter is organized in four sections. The first one contains a brief description of HFA main characteristics and innovative features. In the second section, an analysis of HFA impact during these ten years is carried out, underlining what priorities and activities have been really implemented in practice, what activities has been pervasively developed and what elements are still in need of further actions. The drivers of success or failure of HFA priorities and actions are identified and discussed. The third section is oriented to identify how risk scenario has changed during these ten years and what are the new needs and new occurrences emerged that should be considered in the future strategy for DRR. For instance, the deepening of climate change problem will not only add to the existing drivers of risk new menaces, it needs a decisive change in urban development approach: a significant increase in the extremes and their intensities needs for a transformed development paradigm. In the last section, main themes of a renewed approach to DRR are identified. Main results include: weaknesses and strengths in HFA implementation are identified; factors that appear to interfere with an integrated approach are pinpointed and discussed; emerging features of future risk scenarios are outlined; main issues of a renewed approach are illustrated.

Seismic Refraction and MASW (Multichannel Analysis of Surface Waves) tests were conducted at two hundred locations in the National Capital Region of Delhi, India. Geophysical data along with the borehole information is used to delineate the study region for engineering purposes. Primary and shear wave profiles were generated using common mid-point method and an attempt has been made to minimize the error between observed and calculated travel times to improve the velocity models. A number of shallow rock engineering parameters such as Concentration Index, Material Index, Density Gradient and Stress Ratio were calculated to assess the subsurface bedrock from a geophysical and engineering prospective. Subsurface information (rock/soil quality) is interpreted using seismic velocity values, consolidation and strength parameters. The study area is then divided into different zones based on the obtained results. The aim of the study is to integrate the geophysical studies with the engineering parameters to help in site characterization for seismic microzonation and hazard estimation.