Littérature scientifique sur le sujet « Unpredictable and predictable natural disasters »
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Articles de revues sur le sujet "Unpredictable and predictable natural disasters"
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Hein, Annette, Laura Condon et Reed Maxwell. « Evaluating the relative importance of precipitation, temperature and land-cover change in the hydrologic response to extreme meteorological drought conditions over the North American High Plains ». Hydrology and Earth System Sciences 23, no 4 (10 avril 2019) : 1931–50. http://dx.doi.org/10.5194/hess-23-1931-2019.
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Abstract. Drought is a natural disaster that may become more common in the future under climate change. It involves changes to temperature, precipitation and/or land cover, but the relative contributions of each of these factors to overall drought severity is not clear. Here we apply a high-resolution integrated hydrologic model of the High Plains to explore the individual importance of each of these factors and the feedbacks between them. The model was constructed using ParFlow-CLM, which represents surface and subsurface processes in detail with physically based equations. Numerical experiments were run to perturb vegetation, precipitation and temperature separately and in combination. Results show that decreased precipitation caused larger anomalies in evapotranspiration, soil moisture, stream flow and water table levels than increased temperature or disturbed land cover did. However, these factors are not linearly additive when applied in combination; some effects of multifactor runs came from interactions between temperature, precipitation and land cover. Spatial scale was important in characterizing impacts, as unpredictable and nonlinear impacts at small scales aggregate to predictable, linear large-scale behavior.
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Sabrah, Nashwan, et Nabeel T. Alsohybe. « Toward Better Resilience during the War Crisis ; Case Study of Three Microfinance Institutions in Yemen ». Business and Economic Research 9, no 2 (7 juin 2019) : 207. http://dx.doi.org/10.5296/ber.v9i2.14896.
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As a crisis, man-made or natural disaster, strikes, business management struggles to maintain business continuity and sustainability. The management takes several approaches to keep business running during turbulent times such as proactive approach and ad hoc approach. Organizations proactively prepare plans to face predictable changes; however, sometimes the unpredictable changes become very complicated and challenging which would negatively affect these organizations and their business continuity. As a result, it is very crucial for any organization to be well prepared to keep its business running during turbulent times. Currently, there is a major war going on in Yemen since 2015 that negatively affects most of the business sectors in Yemen. Microfinance sector is considered a very important sector in the country, and it is one of the sectors that is affected and hit hard by the ongoing conflict. Thus, a microfinance industry leader sought solutions. The researchers conducted a qualitative study with three microfinance pioneers in Yemen and interviewed 11 professionals from different management levels. This study found that the operation of the studied institutions has been interrupted by four majors’ turbulences and challenged by three market changes which drove these Microfinance Institutions MFIs to adapt their strategies and practices.
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Li, Qingchen, Guangxi Cao et Wei Xu. « Relationship research between meteorological disasters and stock markets based on a multifractal detrending moving average algorithm ». International Journal of Modern Physics B 32, no 01 (8 janvier 2018) : 1750267. http://dx.doi.org/10.1142/s0217979217502678.
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Based on a multifractal detrending moving average algorithm (MFDMA), this study uses the fractionally autoregressive integrated moving average process (ARFIMA) to demonstrate the effectiveness of MFDMA in the detection of auto-correlation at different sample lengths and to simulate some artificial time series with the same length as the actual sample interval. We analyze the effect of predictable and unpredictable meteorological disasters on the US and Chinese stock markets and the degree of long memory in different sectors. Furthermore, we conduct a preliminary investigation to determine whether the fluctuations of financial markets caused by meteorological disasters are derived from the normal evolution of the financial system itself or not. We also propose several reasonable recommendations.
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Eren, Emrah, et Omer Faruk Bay. « Critical Communication Simulation in Natural Disaster Situations ». International Journal of Engineering Research in Electronics and Communication Engineering 9, no 4 (25 avril 2022) : 1–3. http://dx.doi.org/10.36647/ijerece/09.04.a001.
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After natural disasters such as earthquake, flood, hurricane; because of damage to telephone and internet networks and instantaneous traffic density created by subscribers, voice and data networks lose their functions to a large extent. Service providers make many practices to prevent service interruptions in communication networks and not to disrupt the operation of the protocols used during and after a natural disaster. Since natural disasters are non-repeatable and unpredictable, these measures cannot be carried out with comprehensive assessments. In this context, simulation software is the best approach for testing communication networks in case of natural disasters. In this study, the issue of analyzing the outages that may occur in the infrastructure of Telecom service providers after natural disasters with network simulations is mentioned.
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Li, Shanshan, et Xiaoling Sun. « Application of public emotion feature extraction algorithm based on social media communication in public opinion analysis of natural disasters ». PeerJ Computer Science 9 (16 juin 2023) : e1417. http://dx.doi.org/10.7717/peerj-cs.1417.
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Natural disasters are usually sudden and unpredictable, so it is too difficult to infer them. Reducing the impact of sudden natural disasters on the economy and society is a very effective method to control public opinion about disasters and reconstruct them after disasters through social media. Thus, we propose a public sentiment feature extraction method by social media transmission to realize the intelligent analysis of natural disaster public opinion. Firstly, we offer a public opinion analysis method based on emotional features, which uses feature extraction and Transformer technology to perceive the sentiment in public opinion samples. Then, the extracted features are used to identify the public emotions intelligently, and the collection of public emotions in natural disasters is realized. Finally, through the collected emotional information, the public’s demands and needs in natural disasters are obtained, and the natural disaster public opinion analysis system based on social media communication is realized. Experiments demonstrate that our algorithm can identify the category of public opinion on natural disasters with an accuracy of 90.54%. In addition, our natural disaster public opinion analysis system can deconstruct the current situation of natural disasters from point to point and grasp the disaster situation in real-time.
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Kumar, Dinesh, Ashutosh Sharma, Rajiv Kumar et Neeru Sharma. « A Holistic Survey on Disaster and Disruption in Optical Communication Network ». Recent Advances in Electrical & ; Electronic Engineering (Formerly Recent Patents on Electrical & ; Electronic Engineering) 13, no 2 (27 avril 2020) : 130–35. http://dx.doi.org/10.2174/2352096512666190215141938.
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Background: This paper is a review of optical fiber communications and also presents the different types of disasters and different protection schemes to combat these disasters. In the optical communication network, the failure of a network caused by disasters (e.g. predictable disaster, unpredictable disaster, Intentional attacks) leads to the failure of several optical communication channels and huge data loss. Most of the previous works on optical network survivability assume that the failures are going to occur in future, and the network is made survivable to ensure connectivity in events of failures. With the advancements in technology, the predictions of tornados, cyclone and landslides are becoming more accurate by using some early warning systems. Objective: Significant improvement in optical communication network survivability can be achieved using our proposed protection scheme in the event of a major earthquake, cloud burst and landslides. Conclusion: The review concludes that a large amount of data could be lost even if there is a very short disruption in the optical backbone network.
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Fan, Rongquan, Wenhui Zeng, Ziqiang Ming, Wentao Zhang, Ruirui Huang et Junyong Liu. « Risk Reliability Assessment of Transmission Lines under Multiple Natural Disasters in Modern Power Systems ». Energies 16, no 18 (12 septembre 2023) : 6548. http://dx.doi.org/10.3390/en16186548.
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Climate change has led to more frequent extreme weather events, and various natural disasters have posed risks to the operation of transmission lines. Line failures caused by natural disasters are unpredictable and bring additional maintenance work. Therefore, this paper proposes a transmission line risk reliability assessment method that considers the combined effects of multiple natural disasters. This method establishes a theory of disaster risk quantification that considers the probability of the occurrence of the risk, the degree of the impact of the risk on the line, and the severity of the risk disaster. The risk weights for different natural disasters are calculated by combining a hierarchical analysis and entropy weighting methods. The example of a transmission line risk assessment under the combined effects of multiple natural disasters for a Sichuan region verifies the proposed method’s effectiveness. The results show that the method effectively assesses the operational risk to transmission lines under the combined effects of natural disasters. The assessment results can be used for disaster recovery and line risk prevention.
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Adiwena, Bartolomeus Yofana, Audrey Eleanor Yuliana Azury Mangimbulur, Azzahra Nurmaliza Putri, Ghea Farah Fahira et Maria Angelina Krista. « Description Of The Traumatic Experience Of The Dinar Indah Housing Flood Disaster Victims ». INDONESIAN JOURNAL OF ECONOMIC AND SOCIAL SCIENCE 1, no 2 (28 octobre 2023) : 28–32. http://dx.doi.org/10.30989/ijess.v2i1.1210.
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Unpredictable natural disasters can traumatize a person and disrupt the victim's daily activities. Moreover, if this is the first time a victim has experienced a natural disaster. The trauma that arises and the impact on them will be different from the victims who have experienced several natural disasters. In this case, the researcher will provide an overview of the trauma experienced by flood victims who have only experienced floods once, a total of four people. This study uses qualitative data collection techniques using interviews, observation and phenomenological data analysis techniques. The results showed that natural disasters that occurred to participants caused trauma due to this unpleasant experience. This impacts participants who are more easily anxious and afraid when symptoms of natural disasters appear—looking at the results of the interviews in analyzing the symptoms of trauma felt by the participants and how disturbing they were in carrying out their daily activities.
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Sobhana, Mummaneni, Smitha Chowdary Chaparala, Devaganugula N. V. S. L. S. Indira et Konduru Kranthi Kumar. « A disaster classification application using convolutional neural network by performing data augmentation ». Indonesian Journal of Electrical Engineering and Computer Science 27, no 3 (1 septembre 2022) : 1712. http://dx.doi.org/10.11591/ijeecs.v27.i3.pp1712-1720.
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Natural disasters are catastrophic events and cause havoc to human life. These events occur in the most unpredictable times and are beyond human control. The aftermath of the disasters is devastating ranging from loss of life to relocation of large groups of the population. With the development in the domains of computer vision (CV) and Image processing, machine learning and deep learning models can integrate images and perform predictions. Deep learning techniques employ many robust techniques and provide significant results even in the case of images. The detection of natural disasters without human intervention requires the help of deep learning techniques. The project aims to employ a multi-layered convolutional neural network (CNN) organization to classify the images related to natural disasters related to earthquakes, floods, cyclones, and wildfires.
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Rosyid, Moh. « Memaknai Terjadinya Bencana Alam Merujuk pada Kajian Tafsir ». Islamika : Jurnal Ilmu-Ilmu Keislaman 20, no 01 (30 juillet 2020) : 31–39. http://dx.doi.org/10.32939/islamika.v20i01.539.
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The purpose of writing this text is to make Al-Quran a place to ask questions and remember the greatness of God. The closer humans are to God, humans always care for nature with full awareness. Messages of Al-Quran and newspaper coverage with methode tafsir bi ar-Ra’yi atau al-’aqli by qualitative descriptive analysis can be used as a life lesson. It is to realize that Divine power is second to none because He is the Almighty. Human negligence in caring for nature will cause disaster / natural disasters. Disasters are not always predictable by the sophistication of technology and science in terms of when to come and when the end of natural disasters due to human limitations. The Koran illustrates that natural disasters have occurred in humans since the beginning of time. The event has a variety of meanings to be used as material for life lessons.
Thèses sur le sujet "Unpredictable and predictable natural disasters"
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Li, Jing. « Optimization of emergency logistics for natural disasters ». Electronic Thesis or Diss., université Paris-Saclay, 2024. https://www.biblio.univ-evry.fr/theses/2024/interne/2024UPASG072.pdf.
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Le problème de planification de la logistique d'urgence (ELPP) pour les catastrophes naturelles a attiré une attention significative ces dernières années en raison de la fréquence croissante et des impacts graves sur la santé publique et la sécurité. Ces catastrophes peuvent être classées en deux types : prévisibles et imprévisibles. Cette étude se concentre sur l'amélioration de l'efficacité et de l'efficience des secours pour les deux types de catastrophes.Les catastrophes imprévisibles, survenant soudainement avec peu ou sans avertissement préalable, présentent de sérieux défis pour les organisations de secours. Les recherches actuelles sur les ELPPs pour les catastrophes imprévisibles (ELPPs-UD) négligent le rôle des donations ainsi que des facteurs clés simultanément, tels que la demande, le transport et l'approvisionnement incertains, qui affectent ensemble l'efficacité des interventions. Pour combler cette lacune, le premier travail de la thèse étudie un nouveau ELPP-UD qui considère la corrélation entre les donations et la gravité des catastrophes, ainsi que diverses incertitudes. Un nouveau modèle d'optimisation robuste à deux étapes est construit et des algorithmes sur mesure de génération de colonnes et de contraintes (CCG) sont développés pour résoudre ce problème. Les expériences numériques à partir d'une étude de cas et d'instances générées aléatoirement valident l'efficacité et l'efficience du modèle et des algorithmes proposés.Les catastrophes naturelles prévisibles sont caractérisées par leur capacité à être prévues bien à l'avance. Les informations prévisionnelles appropriées peuvent être utilisées pour des alertes précoces et une préparation aux urgences afin d'améliorer l'efficacité des secours. Cependant, la littérature existante sur les problèmes de planification de la logistique d'urgence pour les catastrophes prévisibles (ELPP-PD) présente plusieurs lacunes : 1) Aucune étude n'examine les activités de secours en considérant simultanément les trois étapes: avant les alertes, entre une alerte et le déclenchement de la catastrophe, et après la catastrophe. 2) La plupart des études ne tiennent pas compte des incertitudes temporelles liées à la trajectoire et à l'intensité d'une catastrophe. 3) Il y a un manque de prise en compte des options de transport impliquant la participation du public, telles que les transporteurs “crowd-sourced”, même si leur rôle peut être crucial pour assurer une réponse rapide en cas de catastrophe.Pour combler ces lacunes, le deuxième travail de la thèse étudie un nouveau ELPP-PD qui prend en compte simultanément les décisions de secours en trois étapes et les incertitudes temporelles liées à la trajectoire et à l'intensité d'une catastrophe. Un nouveau modèle d'optimisation robuste à trois étapes est proposé. Pour résoudre le problème efficacement, un modèle déterministe équivalent est proposé, basé sur une analyse théorique, puis un algorithme de recouvrement progressif amélioré est développé. L'efficacité et l'efficience du modèle et de l'algorithme proposés sont évaluées par une étude de cas et des instances générées aléatoirement.La troisième partie de la thèse examine un ELPP-PD innovant qui intègre l'utilisation de supports “crowd-sourced”. Pour ce problème, un nouveau modèle robuste à base de contraintes en probabilité sur plusieurs périodes est proposé, qui est ensuite converti en un modèle déterministe équivalent par une analyse théorique. Un algorithme heuristique basé sur la CCG est développé pour résoudre efficacement le problème. Les résultats expérimentaux basés sur une étude de cas et des instances générées aléatoirement démontrent la bonne performance du modèle et de l'algorithme proposésThe emergency logistics planning problem (ELPP) for natural disasters has gained significant attention in recent years due to the increasing frequency and severe impacts of these events on public health and safety. These disasters can be classified into two types: predictable and unpredictable. This study focuses on improving the effectiveness and efficiency of relief efforts for both types of disasters.Unpredictable natural disasters, which occur suddenly with little to no warning, present significant challenges to relief organizations. Existing literature on ELPPs for unpredictable natural disasters (ELPPs-UD) fails to consider the impact of in-kind donations on relief activities and does not fully explore key factors in disaster relief together, such as uncertain demand, transportation, and supply. These oversights can affect the efficiency of relief activities. To bridge this gap, we first study a new ELPP-UD that considers the correlation between in-kind donations and disaster severity, as well as various uncertainties. A novel two-stage distributionally robust optimization model is constructed, and tailor-made column-and-constraint generation (CCG) algorithms are developed to solve the problem. Numerical experiments on a case study and randomly generated instances validate the effectiveness and efficiency of the proposed model and algorithms.Predictable natural disasters are characterized by their ability to be forecasted well in advance. Appropriate forecasting information can be used for earlier disaster warnings and emergency preparedness to improve relief effectiveness. However, the existing literature on ELPPs for predictable disasters (ELPPs-PD) has several research gaps: 1) No study fully considers the relief activities at all three stages simultaneously: pre-warnings, between a warning and the onset of the disaster, and post-disaster. 2) Most studies do not consider both time-dependent uncertainties in the disaster's trajectory and intensity. 3) There is a lack of consideration for transportation options that involve public participation, i.e., crowd-sourced carriers, even though they can be crucial in ensuring a timely disaster response.To bridge these research gaps, the second work of the thesis investigates a novel ELPP-PD that accounts for three-stage relief decisions and time-dependent uncertainties in the disaster's trajectory and intensity together. A novel three-stage distributionally robust optimization model is proposed for the problem. To efficiently resolve the problem, an equivalent deterministic model is provided based on theoretical analysis, and then an enhanced progressive hedging algorithm is proposed. The effectiveness and efficiency of the proposed model and algorithm are evaluated through a case study and randomly generated instances.The third part of the thesis further examines an innovative ELPP-PD that incorporates the use of crowd-sourced carriers. A novel multi-period robust chance-constraint model is proposed, which is then converted into an equivalent deterministic model through theoretical analysis. A heuristic-based CCG algorithm is then developed to effectively solve the problem. Experimental results based on a case study and randomly generated instances demonstrate the good performance of the proposed model and algorithm
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Lazraq, Byström Adam. « Besöksnäringens stabilitet och sårbarhet i Stockholms stad : En kvalitativ studie om Stockholms stads besöksnäring ». Thesis, Umeå universitet, Institutionen för geografi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-172344.
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The tourism sector in Stockholms city, Sweden, is a dynamic industry that through the years has generated large revenues and job openings. Unpredictable events such as terrorism, pandemics, natural disasters and climate changes, may have great imapct on the tourism sector. This may be true to most cities in the world including Stockholm. in this thesis, the effect of various unpredictable events has been investigated through interviews with city of Stockholm and the authority for community protection and preparedness. In use of strenghts, weaknesses, opportunities and threats (SWOT-analys). The main conclusion of this thesis is that the Covid-19 pandemic (year 2020) has shown that the emergency preparations for unpredictable events are incorrectly dimensiond. This means that the city of Stockholm needs to work more proactively in the future to ensure that the tourism sector is not jeopardized during upcoming unpredictable events.
Livres sur le sujet "Unpredictable and predictable natural disasters"
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Acts of God : The Old farmer's almanac unpredictable guide to weather and natural disasters. New York : Random House, 1993.
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David, Nash, et James Talmage Stevens. 52 Prepper Projects : A Project a Week to Help You Prepare for the Unpredictable. Skyhorse Publishing Company, Incorporated, 2013.
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David, Nash, et James Talmage Stevens. 52 Prepper Projects : A Project a Week to Help You Prepare for the Unpredictable. SKYHORSE, 2013.
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Lee, Martha F. Conspiracy Rising. ABC-CLIO, LLC, 2011. http://dx.doi.org/10.5040/9798400630873.
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This book offers a thoughtful analysis of how and why conspiracy thinking has become a popular mode of political discourse in the United States. How did conspiracy thinking become such a significant and surprisingly widely accepted form of political thinking in the United States? What compels people to respond to devastating, unpredictable events—terrorist acts, wars, natural disasters, economic upheavals—with the conviction that nothing is a coincidence, nothing is as it seems, and everything is connected? Conspiracy Rising: Conspiracy Thinking and American Public Life argues that while outlandish paranoid theories themselves may seem nonsensical, the thread of conspiracy thinking throughout American history is a both a byproduct of our democratic form of government and a very real threat to it. From the Illuminati, the Knights Templar, and the Freemasons to the government hiding aliens and faking the moon landing; from the New World Order to the Obama "Birthers," the book explores the enduring popularity of a number of American conspiracy theories, showing how the conspiracy hysteria that may provoke disdain and apathy in the general public, can become a source of dangerous extremism.
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Thuesen, Peter J. Tornado God. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190680282.001.0001.
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One of the earliest sources of humanity’s religious impulse was severe weather, which ancient peoples attributed to the wrath of storm gods. Enlightenment thinkers derided such beliefs as superstition and predicted they would pass away as humans became more scientifically and theologically sophisticated. But in America, scientific and theological hubris came face to face with the tornado, nature’s most violent windstorm. Striking the United States more than any other nation, tornadoes have consistently defied scientists’ efforts to unlock their secrets. Meteorologists now acknowledge that even the most powerful computers will likely never be able to predict a tornado’s precise path. Similarly, tornadoes have repeatedly brought Americans to the outer limits of theology, drawing them into the vortex of such mysteries as how to reconcile suffering with a loving God and whether there is underlying purpose or randomness in the universe. In this groundbreaking history, Peter Thuesen captures the harrowing drama of tornadoes, as clergy, theologians, meteorologists, and ordinary citizens struggle to make sense of these death-dealing tempests. He argues that, in the tornado, Americans experience something that is at once culturally peculiar (the indigenous storm of the national imagination) and religiously primal (the sense of awe before an unpredictable and mysterious power). He also shows that, in an era of climate change, the weather raises the issue of society’s complicity in natural disasters. In the whirlwind, Americans confront the question of their own destiny—how much is self-determined and how much is beyond human understanding or control.
Chapitres de livres sur le sujet "Unpredictable and predictable natural disasters"
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Birkland, Thomas A., et Megan K. Warnement. « Critical Infrastructure in Extreme Events ». Dans Controversies in Science and Technology. Oxford University Press, 2014. http://dx.doi.org/10.1093/oso/9780199383771.003.0006.
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The September 11 attacks triggered concern about the performance of “critical” infrastructure on which social, political, and economic activity depend. The attacks moved terrorism to the top of the national security agenda and led to significant legislative, regulatory, and behavioral changes. Furthermore, the shift in focus to the threat of terrorism diminished policymakers’ appreciation and preparation for the natural disasters that communities typically face every year (Boin and McConnell 2007). The increasing number of declared natural disasters, coupled with the threat of terrorism, suggests that “extreme events” can lead to failures in critical infrastructure. These failures have national implications that can ripple through society and the economy. This chapter is about the performance of our interdependent infrastructure systems in extreme events, which are outside shocks to infrastructures; we do not consider failures internal to a system, such as major power blackouts that are not triggered by some significant external shock. We argue that “infrastructure” is best considered as systems of technical and social systems that interact in both predictable and unpredictable ways. As such, we cannot simply consider their design and performance as solely technological problems. There is no one universally accepted definition of “infrastructure.” The Compact Oxford English Dictionary defines the term as “the basic physical and organizational structures and facilities (e.g., buildings, roads, power supplies) needed for the operation of a society or enterprise” but uses the example sentence “the social and economic infrastructure of a country,” suggesting that the term is very broad and very vague. The term came into widespread use in the 1960s and 1970s to mean “public works” (Boin and McConnell 2007). Alternative definitions link “public works” with narrowly defined systems, such as telecommunications and electrical systems, as well as broader systems such as finance, health care, and food production and distribution. The broader definition of infrastructure, which gained currency after September 11, refers to what’s become known as “critical” infrastructure.
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Lade, Clare, Paul Strickland, Elspeth Frew, Paul Willard, Sandra Cherro Osorio, Swati Nagpal et Peter Vitartas. « Future Proofing a Crisis ». Dans International Tourism Futures. Goodfellow Publishers, 2020. http://dx.doi.org/10.23912/9781911635222-4746.
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The nature of the international tourism industry makes it prone to crises. Its service characteristics together with the number of potential external threats considered beyond its control, contribute to its susceptibility and make the risks difficult to manage (Evans and Elphick, 2005; Santana, 2008; Pforr, 2009; Nian et al., 2019). Interruptions to services at the destination itself and within transit routes, as well as the (mis)perceptions of consumers in distant markets, contribute to an increased vulnerability to the short and longer term effects of a crisis The UN World Tourism Organisation (UNWTO) considers a crisis, in the context of the travel and tourism industry, as ‘any unexpected event that affects traveller confidence in a destination and interferes with the ability to continue operating normally’ (2011). The terms ‘crisis’ and ‘disaster’ are often used interchangeably within the literature although it may be argued a difference in meaning exists (Rindrasih et al., 2019). The scale and responsibility, or control factors within the causation of the event, appear to be the key elements used to distinguish the two terms. Faulkner (2001: 136), for example, makes the distinction between the two terms by defining a crisis as ‘a self-inflicted event caused by problems, such as inept management structures and practices or a failure to adapt to changes’; and a disaster as ‘a situation in which an enterprise (or group of enterprises) is confronted with sudden unpredictable and catastrophic changes over which it has little control’. Within a tourism context, Bierman (2016) makes the distinction of crises as being either Category 1 or 2. Category 1 crises are beyond the control of management and include natural disasters, acts of terrorism and war, crime, political conflicts and sudden economic downturns. Category 2 crises result from management’s failure to act or implement processes to prepare for or deal with predictable risks such as high staff turnover, lack of insurance in a situation of fire or flood, service and equipment failure, financial fraud and loss of data (Bierman, 2016). For the purpose of this chapter discussion, a definition adapted from Beirman (2003: 4) relating to a destination crisis will be used, primarily focused on the large-scale nature of the crisis events discussed, these being considered as Category 1, and beyond the control of destination’s management and tourism authorities
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Cullen, Kathleen E., Omid A. Zobeiri, Kantapon Pum Wiboonsaksakul, Lin Wang, Oliver R. Stanley, Olivia M. E. Leavitt et Hui Ho Vanessa Chang. « The Processing of Predictable Versus Unpredictable Motion Signals During Natural Self-Motion ». Dans The Senses : A Comprehensive Reference, 483–95. Elsevier, 2020. http://dx.doi.org/10.1016/b978-0-12-809324-5.24178-3.
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Tapia, Andrea H., Nicklaus A. Giacobe, Pamela J. Soule et Nicolas James LaLone. « Scaling 911 Texting for Large-Scale Disasters ». Dans Emergency and Disaster Management, 707–20. IGI Global, 2019. http://dx.doi.org/10.4018/978-1-5225-6195-8.ch032.
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In a mass crisis event, Emergency Operation Centers (EOC) cannot meet the demand of thousands of individuals trying to alert or request emergency services. However, new technology, driven by the right policy and tested for strengths and weaknesses in a data rich, semi-predictable environment, can help to address current PSAP limitations. In this paper the authors present a system that aims to provide real-time data to emergency managers during a crisis event in such an environment – a college town during a football game or similarly attended event. The system is designed to accept, sort, triage and deliver hundreds of direct text messages from populations engaged in a crisis to emergency management staff who can respond. They posit that when a municipal or county-level EOC is cross-housed with a University EOC, multiple opportunities for development and funding occur. Universities can provide the technical expertise, funding, staffing, development and testing for systems that serve the EOC. Most importantly, Universities also provide disaster-like events that can be used as proxies for unpredictable mass crises during which more valid and reliable testing can occur. The authors present preliminary findings from a text-to-emergency service currently in use by Penn State University Athletics.
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Nazir, Sajid, Zhang Yu et Khawaja Masood Raza. « Multimodal Transport and the Integration of Transport Modes to Support Disaster Relief Operations ». Dans Emerging Trends in Sustainable Supply Chain Management and Green Logistics, 98–120. IGI Global, 2023. http://dx.doi.org/10.4018/978-1-6684-6663-6.ch005.
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Over the last few years, with the rise of natural/man-made disasters, the importance of the humanitarian supply chain has also received a significant value. Humanitarian supply chain performs under special circumstances compared to commercial supply chain such as lack of communication system, electricity, and destabilized transport infrastructure after a disaster. However, disasters are unpredictable; therefore, the demand for supplies (relief items), casualties, and required transportation modes to access the affected area are also unpredictable. Thus, the integration of different modes of transportation is essential to encounter any disaster situation promptly, such as disasters in South Asia in 2001, which caused the death of thousands due to lack of transport infrastructure, inadequate disaster relief planning, and lack of transport integration.
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Baxter, Peter J. « Disasters : Earthquakes, hurricanes, floods, and volcanic eruptions ». Dans Oxford Textbook of Medicine, sous la direction de Jon G. Ayres, 1713–18. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780198746690.003.0211.
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Natural disasters (including earthquakes, volcanic eruptions, hurricanes, floods) cause tens of thousands of deaths and adversely affect the lives of hundreds of millions of people every year. The trend is for the impacts to increase alongside the continuing expansion of human populations into regions at risk and with environmental degradation making human settlements more vulnerable, especially in heavily urbanized areas and megacities. This reckless development is going on in most countries of the world, even in places prone to natural disasters. Recent remarkable advances in forecasting weather-related disasters (hurricanes and floods) have to be matched with adequate disaster preparedness in those communities at high risk if they are to be translated into effective warnings, especially in low-income countries. Earthquakes remain notoriously unpredictable and have the greatest mortality toll of all natural disasters.
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Muneer, Saqib. « Risk and Uncertainty Factors in Managerial Economics ». Dans Advances in Human Resources Management and Organizational Development, 153–76. IGI Global, 2024. http://dx.doi.org/10.4018/979-8-3693-5733-0.ch008.
Texte intégralRésumé :
The concept of risk in managerial economics encompasses various unexpected events such as natural disasters, risk, economic challenges, uncertainty or product failures that lead to undesirable outcomes. Risk arises from incomplete information about future events, which makes the results unpredictable. The inherent uncertainty of the future because of the unpredictable nature of the universe, further complicates the understanding and management of risk. Scientific uncertainty, defined as any deviation from complete determinism, illustrates the difficulty in clearly defining risk. Sometimes managerial economics explores risk through its two primary dimensions, highlighting its complexity and the challenges it presents to decision-makers.
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Dimitrova, Diana. « Medical Provision of the Population within an Outbreak of a Traumatic Defeat an Earthquake : A Fundamental Tool of the Staged Health Risk Management ». Dans Natural Hazards - Impacts, Adjustments and Resilience. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.94259.
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The most destructive and unpredictable disasters around the world are determined earthquakes. Various consequences are reported as possible negative effects and therewithal health-related of them. The identification and classification of the different types of health risk factors is an initial goal in an uncomplicated earthquake setting and a fundamental tool to a good understanding and effective organization of the health care system (HCS) in case of complicated medical situation. The health care system works at high tension with considerable difficulties due to the calamity of a large magnitude outbreak of a traumatic defeat such as an earthquake. In conditions of the worst-case earthquake scenario with the subsequent provoked multi-secondary disasters and with multi-secondary risk factors possibilities to take accurate solutions is a real challenge for the health risk manager. They are available critically low resource constraints. Two main critical points are formed. On the one hand the description of a structure of mass victim and achievement high quality medical triage in complicated setting due to earthquakes is a conceptual medical stage of health risk management. On the other hand it is a main step of medical provision of the population and a step of risk reduction strategy.
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Bairg1, Stephan. « Applying The Principles Of Adaptive Policy Design To Environmental Taxes ». Dans Critical Issues In Environmental Taxation, 173–81. Oxford University PressOxford, 2008. http://dx.doi.org/10.1093/oso/9780199542185.003.0007.
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Abstract We live in a world where the climate is changing, energy prices are highly unpredictable, international trade rules are in a state of flux, and domestic security considerations in many countries are so important that they permeate or overwhelm all other policy issues. At the same time, scientific knowledge is advancing on many fronts, also in unpredictable directions. We are uncertain about both the future of the natural world and how humanity and society will respond to what-ever changes occur. The impacts of all of these factors are not predictable. We do not know what will be the impact on ecosystem functioning, or global and local income distribution, or on aggregate economic output. In particular, we don’t know what the combined impacts of all of the changes will be—on farm and fishery production, on water supplies and health care systems, on financial markets, or on government revenues and the demand for services. Governments’ dilemma is that they are required to make policy in this situation of great uncertainty. The dilemma arises because policy is normally made on the basis of relative certainty. Policy designers are used to working with constants and normals, such as land mass, population, stable infrastructure, and market economies that move within a predictable range. Therefore, when they suggest policy interventions they often feel that they can predict the results. But in this new state of uncertainty in which governments must operate, this goal may be unattainable with normal approaches.3 This chapter examines how policy-makers, and particularly tax designers, might be able to design policies that will cope well with uncertainty. The sections below will first outline the sources of the uncertainty, and then discuss the issues that this raises for policy-makers.
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Treadwell, Katie L. « Strategic Leadership in Times of Crisis ». Dans Encyclopedia of Strategic Leadership and Management, 1599–611. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-1049-9.ch111.
Texte intégralRésumé :
With increasingly commonplace threats of intentional violence, citywide terrorism, natural disasters, and unpredictable accidents, leaders navigate disaster situations on a more frequent basis than they may be prepared to encounter. Escalating media connectivity and social networks put organizations and leaders at greater risk for public perception crises on a routine basis, forcing them to take preventative steps well in advance of potential crises and remain vigilant in responding to such situations. The following chapter explores emergency response through a strategic lens, offering a background in crisis management literature and a theoretical basis for learning in the midst of disaster. Drawing upon an extensive study of higher education professionals who encountered high-profile disasters, the author offers practical strategies to navigate crises while maintaining individual and organizational character. Doing so may determine both the victims' experience with the tragedy and the public's long-term perception of the organization.
Actes de conférences sur le sujet "Unpredictable and predictable natural disasters"
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Mohammed, Amir, Craig Ramlal, Arvind Singh, Sean Rocke et Daniel Goitia. « A SIMULATION FRAMEWORK FOR CONTROLLED CRITICAL INFRASTRUCTURES SUBJECT TO NATURAL DISASTERS ». Dans International Conference on Emerging Trends in Engineering & Technology (IConETech-2020). Faculty of Engineering, The University of the West Indies, St. Augustine, 2020. http://dx.doi.org/10.47412/fzep7016.
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Natural disasters are inherently unpredictable and can cause major damage to critical infrastructures in cities and loss of life. In this study, a simulation and control framework was developed for evaluating response decisions for natural disaster scenarios with the objective of minimizing the casualties generated from within the simulation. The package was developed in MATLAB Simulink using the infrastructure interdependencies simulator (I2Sim) with a test system of six small residences, one large residence, two health centres, one large hospital, three water pumps of varying capacities and one energy production cell. The research focused on the development of heuristic controllers to evaluate the best possible outcome given the disaster scenario simulated to affect critical infrastructure. Response decisions were generated for 625 unique scenarios, this information once grouped, can be used to inform response policies after natural disasters.
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Stanković, Stevan. « Geographical aspect of the environment ». Dans Zbornik radova – VI Kongres geografa Srbije sa medunarodnim ucešcem, 75–82. University of Belgrade - Faculty of Geography, Belgrade, 2024. http://dx.doi.org/10.5937/kongef24008s.
Texte intégralRésumé :
The processes in space and time of our planet are natural and social. They are manifested spontaneously and organized. They can be immediate, occasional natural, periodic and permanent, short-term and long-term, uncontrolled and controlled, creative and destructive, historical and contemporary, known and unknown, predictable and unpredictable, unidirectional and multidirectional, easier and harder to solve. The living environment is characterized by the complexity of the connections of numerous elements, the dynamism resulting from the general movement of natural phenomena and man in them, the easier and more difficult predictability of existing processes and changes in the development of living systems and their relations with nonliving nature, the hierarchy that is established over time, as well as uneven relations in space and time, but also conflicting relations in the case of large number of interested parties in the same space.
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Liang, Wenhua, Ishmael Rico et Yu Sun. « An Intelligent System to Enhance Visually-Impaired Navigation and Disaster Assistance using Geo-Based Positioning and Machine Learning ». Dans 10th International Conference on Information Technology Convergence and Services (ITCSE 2021). AIRCC Publishing Corporation, 2021. http://dx.doi.org/10.5121/csit.2021.110907.
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Technological advancement has brought many the convenience that the society used to lack, but unnoticed by many, a population neglected through the age of technology has been the visually impaired population. The visually impaired population has grown through ages with as much desire as everyone else to adventure but lack the confidence and support to do so. Time has transported society to a new phase condensed in big data, but to the visually impaired population, this quick-pace living lifestyle, along with the unpredictable natural disaster and COVID-19 pandemic, has dropped them deeper into a feeling of disconnection from the society. Our application uses the global positioning system to supportthe visually impaired in independent navigation, alerts them in face of natural disasters, and remindsthem to sanitize their devices during the COVID-19 pandemic.
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Santamaria, Giovanni. « Transforming Territories : A Landscape of “In-Tension-Alities” ». Dans 2018 ACSA International Conference. ACSA Press, 2018. http://dx.doi.org/10.35483/acsa.intl.2018.46.
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The flow of people, resources, material and immaterial goods, and at the same time regimes and strategies of control, have always shaped/reshaped our geographies and processes of urbanization. Therefore built and unbuilt landscapes have been characterized by gradual or dramatic changes, leading to new architectural typologies and urban morphologies corresponding to the transformation of means of production, distribution, circulation, consumption and to the shift of political, economic and ideological realms. The effects of these processes on structure and quality of space and life could be described as part of a complex Urban Metabolism¹ which looks at the city and its territory as a complex organism. This dynamic landscape has reached a high level of complexity where natural environments (geology, hydrology, topography) and cultural environments (productive lands, urban settlements, infrastructural networks) need to be synergistically understood as part of an articulated ecological system, with both micro and macro implications. It is the synthesis of geographic-historical contents (collective values), aesthetic-perceptual contents (individual values), and ecological-natural contents (biological values)², influenced more and more by natural and man-made disasters caused by climate change and human conflicts. Since the city as a definable entity and product of predetermined models has become obsolete, we are now called to work with a collage of fragments, heterogeneous and dynamic, often in opposition and unpredictable, subjected to the balance of variable forces, with their own order and rules, and their own ways of evolving, which we have to understand and manage³. This determines the need for new tools and methods to observe, record and assess urban phenomena, and the data regarding them, towards more sensitive interventions.
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Couceiro, Marlene, et Cristina Carvalho. « Clothing and housing : Using materials with adaptable features can improve comfort and safety in emergency situations. » Dans 14th International Conference on Applied Human Factors and Ergonomics (AHFE 2023). AHFE International, 2023. http://dx.doi.org/10.54941/ahfe1003644.
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In this paper, we intend to present adaptable solutions to improve the safety and comfort of users during or after natural catastrophes (earthquakes, eruptions, floods, hurricanes, droughts) or man-made disasters (conflicts and war). We will explore several suggestions, which I will list below: new applications of signage and innovative materials, which allow a more efficient communication in an emergency situation; garments that become shelters, to minimize the negative impact caused by the destruction and loss of the victims' houses; thermochromic materials, reflectors and color used as warning signs, model partitions, lightweight structures, etc. Those are some examples of the features that enable temporary installations to be created in order to relieve human suffering. Conclusions: In this study, we present some versatile, adaptable, and ecological structures, which reflect the environmental and social changes in our western society. We have put together a series of solutions to create temporary shelter. Projects which are a response to the needs of today's world: contemporary nomadism and struggles in renting or buying a house, due to the rising cost of essential goods and the cost of living. The recent past has been marked by a series of unpredictable events: a pandemic, man-made disasters (Russian-Ukrainian War) and natural catastrophes (a heat wave that hit Europe and increased the risk of fire, heavy and persistent rain that caused floods, falling trees and the recent earthquake in Turkey and Syria). Different occurrences that have left several people homeless. When working in extreme conditions and with limited resources, the provision of a shelter can reduce vulnerability in social and economic terms, physical integrity and well-being. It has been found that the development of this type of product has advantages in terms of comfort, mobility, and safety, as it allows for a rapid adaptation and recovery.
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Demer, Joseph L., et Ben T. Crane. « Gaze Stability With Telescopic Spectacles : Challenges of Viewing Up Close and Personal ». Dans Vision Science and its Applications. Washington, D.C. : Optica Publishing Group, 1997. http://dx.doi.org/10.1364/vsia.1997.sua.2.
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Optimal visual function requires that images of interest be maintained on the fovea with sufficient stability, despite unintended but ubiquitous rotations and translations of the head. This gaze stabilization is necessary since retinal image velocities exceeding 2-3°/sec are associated with a log-linear decline in visual acuity(2). We show elsewhere in this volume that, during normal vision, gaze stability is achieved by a combination of angular and linear vestibulo-ocular reflex responses, as well as coordination of coupling between head rotation and translation. The head effectively moves in a broad arc about an axis of rotation anterior to the head. Gaze stabilization during natural activities such as standing and ambulation is most effective during viewing of remote targets, but is degraded with target proximity. Gaze stabilization must also be achieved when subjects wear head-mounted devices such as video or telescopic spectacle magnifiers. Such devices enlarge images on the retina and markedly alter the demands placed on gaze stabilization reflexes. Due to technical limitations, prior studies of the effects of telescopic spectacles emphasized visual enhancement of the gain (compensatory eye velocity divided by head velocity) of the angular vestibulo-ocular reflex (VOR). These studies reported the seemingly paradoxical observation that while large and appropriate enhancements of VOR gain occurred when subjects wearing telescopic spectacles made repetitive, predictable movements(3), gain enhancements were considerably smaller during unpredictable head movements or those incidental to natural activities(4). We investigated this problem by directly measuring gaze stability in all degrees of rotational and translational freedom in naturally-moving subjects wearing telescopic spectacles.
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Su, H. C., et C. S. Tsai. « Application of Seismic Isolation Systems to High-Raised Houses in Lowland Regions ». Dans ASME 2014 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/pvp2014-28346.
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According to the statistics of the World Bank between years 1970–2010, most economy losses caused by disasters in rich countries were due to floods and earthquakes. The East Asia was the most disastrous area in terms of the death toll caused by earthquakes, which proved that the earthquake is unpredictable. To cope with the crisis of the rise of the sea level, the concept of Marine Cities has been proposed. The most famous one among these concepts is the Dutch amphibious house. People living in earthquake and flood prone areas should be aware of the threat from oceans. Therefore, Ministry of Interior in Taiwan passed the rule 4 No. 2 in the chapter of the design and construction regulations to allow the use of high-raised buildings for reducing life and property loss. Furthermore, the most threatening natural hazards we are facing over a long period of time are floods and earthquakes. When are focusing on the flood resistant buildings in flood-prone areas, we should also aim at the prevention of earthquake disasters. The purpose of this study is to simulate the seismic behavior of the high-raised structures with different water levels, which are capable of flood resistance. We also propose a new seismic isolation system for these structures and study its efficiency in protecting these types of structures from earthquake damage. It appears from experimental results that the seismic responses of high-raised houses have been significantly reduced by the proposed device. Experimental results also disclosed that the proposed concept in this study is feasible for protecting structures in lowlands from damage resulting from floods as well as earthquakes.
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Gabriele, Marzia. « DETECTING AND MAPPING FLASH FLOODING WITH SYNTHETIC APERTURE RADAR (SAR) SATELLITE DATA : THE METAPONTO PLAIN CULTURAL LANDSCAPE CASE STUDY ». Dans ARQUEOLÓGICA 2.0 - 9th International Congress & 3rd GEORES - GEOmatics and pREServation. Editorial Universitat Politécnica de Valéncia : Editorial Universitat Politécnica de Valéncia, 2021. http://dx.doi.org/10.4995/arqueologica9.2021.12115.
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Due to Climate change, unpredictable and uncertain weather conditions increase the likelihood of natural disasters, which correlates to major impacts on Cultural Landscapes and Heritage sites. Thanks to SAR sensors, continuous and rapid information can be collected with satellite data. When a sensor generates a directed beam of pulses, terrain returns high-resolution radar-frequency reflected energy, enabling a first effective data implementation, helping to quickly localize where damage occurred during a flash-flood event. This could facilitate after-disaster response through rapid delivery and coordination of rescue operations. Synthetic Aperture Radar (SAR) data is capable of passing through clouds and weather phenomena and continuously monitor a flooding event by plotting its patterns for a cost-effective flood mapping. Free availability of SAR data through the European Space Agency’s (ESA) Sentinel-1 SAR mission created a major opportunity for flood extent monitoring. The chosen case study is the area of the Metaponto Plain in Basilicata, southern Italy, which recently earned a candidacy as UNESCO site. In the effort of protecting Cultural Landscape and archeological Heritage, local authorities have to face multiple challenges coming from climate change and the impact of human activity. The object of this study is the flash-flooding event occurred on the 12th of November 2019, which was reported to be an extreme hydrological event, causing important damages to the agricultural landscapes and cultural heritage sites. The Metaponto area exemplifies multiple pressures deriving from climate change and human activity, thus having to cohabit within an important cultural landscape and archeological heritage. The workflow here presented can be quickly implemented to extract information through simple and effortless algorithms, providing mid-regional scale event maps with a good resolution, and it is formally aimed at user-end Control Centres for putting in place rapid risk mitigation actions.
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Agrawal, J. P. N., et S. P. Srivastava. « Methodology of Risk Management in Pipeline Projects ». Dans ASME 2013 India Oil and Gas Pipeline Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/iogpc2013-9841.
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Organizations of all types and sizes face internal and external factors and influences that make it uncertain whether and when they will achieve their business objectives. The effect this uncertainty has on an organization’s objectives is “RISK”. In recent times all sectors of the economy have shifted focus towards the management of risk as the key to making organizations successful in delivering their objectives while protecting the interests of their stakeholders. Risk may be defined as events or conditions that may occur, and whose occurrence, if it does take place, has a harmful or negative impact on the achievement of the organization’s business objectives. The exposure to the consequences of uncertainty constitutes a risk. Organizations that are most effective and efficient in managing risks to both existing assets and to future growth will, in the long run, outperform those that are less so. Simply put, companies make money by taking intelligent risks and lose money by failing to manage risk intelligently. Risk management is the identification, assessment, and prioritization of risks (defined in ISO 31000 as the effect of uncertainty on objectives, whether positive or negative) followed by coordinated and economical application of resources to minimize, monitor, and control the probability and/or impact of unfortunate events or to maximize the realization of opportunities. Risks can come from uncertainty in financial markets, project failures (at any phase in design, development, production, or sustainment life-cycles), legal liabilities, credit risk, accidents, natural causes and disasters as well as deliberate attack from an adversary, or events of uncertain or unpredictable root-cause. Several risk management standards have been developed including the Project Management Institute, the National Institute of Standards and Technology, actuarial societies, and ISO standards. Methods, definitions and goals vary widely according to whether the risk management method is in the context of project management, security, engineering, industrial processes, financial portfolios, actuarial assessments, or public health and safety. Risk management is a holistic, integrated, structured and disciplined approach to managing risks with the objective of maximizing shareholder’s value. It aligns strategy, processes, people & culture, technology and governance with the purpose of evaluating and managing the uncertainties faced by the organization while creating value. Broadly this paper deals with the objective of risk management along with identification, polarization, mitigation and governance of risks associated with pipeline projects. Further the criteria for assigning the probabilities and impact of an identified risk along with their classification based on its probability and impact are also incorporated in the paper.
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Yang, Zheng, Yike Dang, Shangtong Yang et Xiaoyu Liu. « Analysis of Mechanical Properties and Failure Modes in Thermally Treated Granite with Structural Defects ». Dans 58th U.S. Rock Mechanics/Geomechanics Symposium. ARMA, 2024. http://dx.doi.org/10.56952/arma-2024-0118.
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ABSTRACT: Natural rocks usually contain joints, fractures, etc. However, current research on rocks' mechanical properties after thermal treatment focuses on intact rocks. To make up for this deficiency, we investigated the influence of temperature on the strength, deformation, and crack propagation behavior of granite with single fissures at different angles. The results indicate that: (1) Compared to intact specimens, the strength of defective granite is reduced due to the presence of defects. As the crack angle increases from 0° to 90°, peak strength and elastic modulus decrease and then increase. (2) Between 150°C and 300°C, the peak strength gradually increases. Beyond 300°C, the peak strength decreases with rising temperature. The initiation, propagation, and peak stress of cracks are closely correlated with temperature. (3) At lower temperatures, cracks' propagation speed and direction will change when encountering minerals. For specimens treated with high temperatures, the temperature caused many thermally induced cracks to form in the sample. The cracks no longer sought the minimum resistance path during the propagation process, and the resistance encountered by crack propagation was greatly reduced, resulting in more direct and predictable paths of crack propagation. 1. INTRODUCTION Granite, a crystalline rock commonly found in the Earth's crust, is crucial in understanding crustal movements, geothermal energy development, and deep geotechnical engineering construction. The evolution of its mechanical behavior and fracture mechanisms under high-temperature conditions is particularly significant. As human activities increasingly impact the Earth's environment, the demand for high-temperature geological engineering encompassing nuclear waste disposal and underground energy extraction has surged. Exploring the principles and mechanisms behind temperature's influence on the mechanical properties of granite is thus crucial. Understanding how temperature changes affect thermal expansion, crack development, and strength weakening in rocks holds significant theoretical and practical value. Such knowledge is vital for predicting and preventing geological disasters and optimizing rock engineering designs. Scholars have conducted many studies to study the effect of temperature on rock mechanical properties and damage, with some widely recognized conclusions. For example, the temperature increases the porosity (Li et al., 2020) and permeability (Jiang et al., 2018). Rock's P-wave velocity and density decrease with the increase of temperature (Guo et al., 2020). Pan et al. (Pan et al., 2023)studied granite's strength and deformation characteristics after high temperature and chemical solution treatment through uniaxial compression tests. This study introduces a new statistical damage constitutive model considering initial thermochemical and loading damage. This model is used to examine the effects of thermal and chemical treatments on the damage evolution of granite during uniaxial compression tests. It was found that, up to 150 °C, chemical treatment results in more significant damage than thermal treatment. However, after thermal treatment at 300 °C or higher, thermal damage progressively increases, and the disparity in chemical damage induced by various solutions diminishes. Zhang et al. (Zhang et al., 2016) investigated the thermal effects on the physical and mechanical properties of rocks by analyzing changes in mineral composition, internal structure, and water content. Based on the temperature range of adhesive water, bound water, and structural water escaping, they divided the temperature into three ranges: from room temperature to 100 °C, 100 °C to 300 °C, and 300 °C to 500 °C. In the second and third stages, the porosity, permeability, and acoustic emission signals of the rock significantly increase, while the P-wave velocity continues to decrease. The rapid increase in sample volume and number of microcracks within the temperature range of 400 °C to 500 °C leads to changes in rock mechanical properties. Yavuz et al. (Yavuz et al., 2010) analyzed the influence of thermal damage on the physical properties of five types of carbonate rocks. Microscopic observation shows that the damage degree of rocks at high temperatures varies depending on particle size, porosity, structure, and texture characteristics. Microscopic analysis and P-wave results indicate that the internal structure of the rock is compacted below 150 °C, and the expansion of calcite does not cause significant damage to the rock structure. The compaction of rock structure leads to an increase in P-wave velocity and a decrease in porosity. Most of the damage occurs within 24 hours of the heating time, and further heating treatment has a relatively small impact on the changes in physical properties.
Rapports d'organisations sur le sujet "Unpredictable and predictable natural disasters"
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Briggs, Nicholas E., Robert Bailey Bond et Jerome F. Hajjar. Cyclic Behavior of Steel Headed Stud Anchors in Concrete-filled Steel Deck Diaphragms through Push-out Tests. Northeastern University. Department of Civil and Environmental Engineering., février 2023. http://dx.doi.org/10.17760/d20476962.
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Earthquake disasters in the United States account for $6.1 billion of economic losses each year, much of which is directly linked to infrastructure damage. These natural disasters are unpredictable and represent one of the most difficult design problems in regard to constructing resilient infrastructure. Structural floor and roof diaphragms act as the horizontal portion of the lateral force resisting system (LFRS), distributing the seismically derived inertial loads out from the heavy concrete slabs to the vertical LFRS. Composite concrete-filled steel deck floor and roof diaphragms are ubiquitously used in commercial construction worldwide due to the ease of construction and cost-effective use of structural material. This report presents a series of composite steel deck diaphragm Push-out tests at full scale that explore the effect that cyclic loading has on the strength of steel headed stud anchors. The effect that cyclic loading has on structural performance is explored across the variation of material and geometric parameters in the Push-out specimens, such as concrete density, steel headed stud anchor placement and grouping, steel deck orientation, and edge conditions. As compared to prior tests in the literature, the push-out tests conducted in this work have an extended specimen length that includes four rows of studs along the length rather than the typical two rows of studs, and an ability to impose cyclic loading. This provides novel insight into force flows in the specimens, failure mechanisms, and load distribution between studs and stud groups.
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Briggs, Nicholas E., et Jerome F. Hajjar. Cyclic Seismic Behavior of Concrete-filled Steel Deck Diaphragms. Department of Civil and Environmental Engineering, Northeastern University, septembre 2023. http://dx.doi.org/10.17760/d20593269.
Texte intégralRésumé :
Earthquake disasters in the United States account for $6.1 billion of economic losses each year, much of which is directly linked to infrastructure damage. These natural disasters are unpredictable and represent one of the most difficult design problems regarding constructing resilient infrastructure. Structural floor and roof diaphragms act as the horizontal portion of the lateral force resisting system (LFRS), distributing the seismically derived inertial loads out from the heavy concrete slabs to the vertical LFRS. Concrete-filled steel deck diaphragms are ubiquitously used in steel construction worldwide due to the ease of construction and cost-effective use of material. This report first presents a series of concrete-filled steel deck push-out tests that explores the effect of cyclic loading on the strength of steel headed stud anchors. The effect that cyclic loading has on structural performance is explored across different concrete densities, steel headed stud anchor placements and groupings, steel deck orientations, and edge conditions. As compared to prior tests, the push-out tests conducted in this work included four rows of studs along the length rather than the typical two rows, and an ability to impose cyclic loading. This provided novel insight into force flows, failure mechanisms, and load distribution between studs and stud groups. Most of the specimens also used lightweight concrete, as is common in high seismic zones.Secondly, this report describes a full-scale experimental concrete-filled steel deck diaphragm specimen which explored the cyclic behavior and capacity of this structural system. This experiment builds on previously reported experimental studies. This specimen demonstrated force distribution and flows in an indeterminant floor system and captured realistic boundary conditions and construction practices that affect the performance of this system in building structures. The results showed that concrete-filled steel deck diaphragms fail as expected and may have significant overstrength. Furthermore, a finite element framework is presented that can simulate cyclic fracture through the use of a high-fidelity steel material model. This framework was used and validated against nine experimental push-out specimens tested and documented as part of this research. The simulation capacity provides an avenue to further investigate this structural system through simulated parametric study.