Height Of Surge Research Articles

DEM–SPH Coupling Method for Landslide Surge Based on a GPU Parallel Acceleration Technique

A high-performance DEM–SPH coupling method for landslide surge is proposed based on a graphics processing unit (GPU) parallel acceleration technique. A GPU-based simulation program, namely, G-DeSp, is developed using C++ and Compute Unified Device Architecture language, which can simulate 3D landslide surge with millions of particles precisely and efficiently. A two-phase flow dam-break test is adopted to validate the accuracy and efficiency of G-DeSp. Three-dimensional landslide surge simulations are conducted with the different diameter of solid particles and the maximum climb height of the surge by granular slide and rigid slide is analyzed. Results show that G-DeSp accurately simulates landslide surge, such as the movement and deformation of the landslide, the generation and propagation of surge waves, and the violent interaction of the fluid–solid. The velocity and displacement of the granular slides and surge decrease with the increase in the diameter of solid particles. The maximum climbing height of surge by the rigid slide is 6.5 times that of surge by the granular slide with the same volume, which indicates that the surge hazard induced by the rigid slide is much more serious than that induced by the granular slide.

Improvements to the detection and analysis of external surges in the North Sea

Abstract. External surges are a key component of extreme water levels in the North Sea. Caused by low-pressure cells over the North Atlantic and amplified at the continental shelf, they can drive water-level changes of more than 1 m at the British, Dutch and German coasts. This work describes an improved and semi-automated method to detect external surges in sea surface time histories. The method is used to analyse tide gauge and meteorological records from 1995 to 2020 and to supplement an existing dataset of external surges, which is used in the determination of design heights of coastal protection facilities. Furthermore, external surges are analysed with regard to their annual and decadal variability, corresponding weather conditions, and their interaction with storm surges in the North Sea. A total of 33 % of the 101 external surges occur within close succession of each other, leading to the definition of serial external surges, in which one or more external surges follow less than 72 h after the previous external surge. These serial events tend to occur more often during wind-induced storm surges. Moreover, the co-occurrence with a storm surge increases the height of an external surge by 15 % on average, highlighting the importance of the consideration of combined events in coastal protection strategies. The improved dataset and knowledge about serial external surges extend the available basis for coastal protection in the North Sea region.

Characteristics of negative and undular surges in an impounded channel

ABSTRACT Physical experiments were conducted in an impounded channel to study the propagation of negative surges advancing in still water and evolution of undular surges against an instantaneously varied flow. The results demonstrated that the initial wave height of a negative surge could be accurately predicted using the simple wave solution of the Saint–Venant equations. Moreover, the wave height evolution during surge propagation could be satisfactorily described using the solution by Ippen and Kulin. The main characteristics of an undular surge were strongly correlated to the surge Froude number and turbulent boundary layer development at the toe of the surge. However, the occurrence of wave breaking at the first wave crest was independent of the inflow conditions and was close to the breaking criterion for solitary waves. Furthermore, the present results indicated the largest turbulent Reynolds stress components beneath the wave crests of an undular surge.

Addressing Vaccine Hesitancy during the COVID-19 Pandemic: Learning from the Past and Moving Forward

Excerpt:Anong hirap ang kailangan niyong maranasan para kayo ay magpabakuna na? How much suffering are you willing to risk experiencing to persuade you to go for COVID-19 vaccination?Working at a COVID-19 Referral Center, we probably saw a lot more critically ill COVID-19 patients than in other hospitals in the Philippines. During the height of the Delta surge in 2021, our intensive care units (ICUs) for adults and pediatric critical COVID-19 were always full with a long waiting line. The typical medical history of the patients would be a senior retiree, usually a Lolo (grandfather) or a Lola (grandmother), who needed urgent support to be hooked to a mechanical ventilator because they could not breathe on their own anymore. When asked about their COVID-19 vaccination status, Loloand Lola were often not vaccinated. Other times, the patient may not yet be old enough to be considered a Lolo or Lola but may have illnesses like heart failure, diabetes, hypertension, or on dialysis. They too were often not vaccinated. And occasionally, we admitted small children who would seemingly be out of place in the sea of adult patients in the Emergency Room. One would think that because the very young have not yet been allowed to get vaccinated, the people around them would strive to be vaccinated to protect these little ones. On the contrary, though, we saw many young patients whose exposures to COVID-19 came from their unvaccinated parents. This heartbreaking situation continued despite the intensive COVID-19 vaccination program of our government. When one thinks about it, it is possible that some of the many deaths and sufferings of patients and the anguish of grieving families, as well as the lonely exits of beloved ones dying alone amidst CPR machines and teams, may have been avoided had unvaccinated patients opted to be vaccinated. Now over 2 ½ years into the pandemic with many cases said to be mild, we continue to have a continuous flow of admissions for COVID-19 which fall into the moderate, severe, and even critical COVID-19, and some of them are because they have remained unvaccinated. Where and how can we improve the situation?

Perceived stress of individuals with disabilities in the United States during COVID-19.

This study was conducted to better understand how COVID-19 has impacted the stress, resiliency, and quality of life of people with disabilities near the height of the first surge of the COVID-19 pandemic in the summer of 2020. An online survey of 990 individuals who self-identified as having at least one disability in the United States was conducted. Quality of life, coping/resilience skills, number of identified disabilities, and age were all significantly related to perceived stress. While access to technology was not significantly related to perceived stress, increased use of technology since the pandemic was associated with increased reported stress, though the practical significance was small. There is a need for increased attention to dissemination of information to people with disabilities. Knowledge of medical rights was significantly associated with following social distancing practices and suggests that health knowledge does change behavior. Ensuring that people with disabilities are aware of coping skills and how to promote resilience is a needed area of focus for the field. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The Taal Volcano Eruption and Landfall of Super Typhoon Odette: A Dilogy of Disasters in the Philippines, An Abstract on the Response Strategies of Dr. Jose N. Rodriguez Memorial Hospital and Sanitarium-Philippine Emergency Medical Assistance Team (DJNRMHS PEMAT) for the TAAL and DINAGAT Missions in the Years 2020 and 2021

Background/Introduction:The country’s location makes it vulnerable to natural disasters, hence, the PEMAT’s potential was tested during local disaster response for Taal Volcano Eruption in Batangas last January 2020 and during the aftermath of Super Typhoon Odette in Dinagat Islands last December 2021, amidst COVID-19 surge.Objectives:The primary objective of the deployment was to augment the DOH in the provision of safe, effective, and efficient quality health care services appropriate to the victims’ needs, timely, and coordinated mobilization of DJNRMHS PEMAT, and to evaluate the knowledge and skills acquired in the EMT Basic induction course in disaster response.Method/Description:As per WHO standards, disaster responses conducted by the DJNRMHS PEMAT followed three important phases: pre-mobilization, mobilization, and post-mobilization. The methods used during these phases in Taal and Dinagat missions were the simulation of drills and application of didactics learnt from the EMT Basic Induction Course for Disaster Response conducted by the DOH in collaboration with WHO in 2019.Results/Outcomes:The essential services rendered by DJNRMHS PEMAT, ensuring patient and responder safety despite being at the height of COVID-19 surge, were out-patient, acute emergency, trauma and basic obstetric care, basic laboratory, social welfare, public health, and pharmaceutical to 1,124 victims in the Taal Eruption and 1,089 victims of Typhoon Odette.Conclusion:Safe and effective delivery of quality health care services by PEMAT, a team equipped with knowledge and skills acquired through mentorship, can be achieved with thorough planning, setting of mission objectives, and most importantly, having full support from the management and all stakeholders.

Learning from COVID-19: Cross-sectional e-survey of critical care nurses' satisfaction and experiences of their role in the pandemic response across the United Kingdom.

Since the start of the global COVID-19 pandemic in 2019, critical care nurses across the world have been working under extreme levels of pressure. To understand critical care nurses' experiences of and satisfaction with their role in the pandemic response across the United Kingdom (UK). A cross-sectional electronic survey of critical care nurses (n=339) registered as members of the British Association of Critical Care Nurses. Anonymous quantitative and open-ended question data were collected in March and April 2021 during the height of the second surge of COVID-19 in the UK via an online questionnaire. Quantitative data were analysed using descriptive statistics and free text responses were collated and analysed thematically. There was a response rate of 17.5%. Critical care nurses derived great satisfaction from making a difference during this global crisis and greatly valued teamwork and support from senior nurses. However, nurses consistently expressed concern over the quality of safe patient care, which they perceived to be suboptimal due to staff shortages and a dilution of the specialist skill mix. Together with the high volume of patient deaths, critical care nurses reported that these stressors influenced their personalwell-being. This study provides insights into the key lessons health care leaders must consider when managing the response to the demands and challenges of the ongoing COVID-19 pandemic. COVID-19 is unpredictable in its course, and what future variants might mean in terms of transmissibility, severity and resultant pressures to critical care remains unknown. Future responses to the challenges that critical care faces must consider nurses' experiences and create an environment that engenders supportive teamwork, facilitates excellent nursing practice and effective safe patient care where critical care nursing may thrive.

Noninferiority of Subcutaneous Versus Intravenous Casirivimab/Imdevimab for Outpatient Treatment of SARS-CoV-2 in a Real-World Setting.

Monoclonal antibody (mAb) therapy has emerged as one of the mainstay treatment options for SARS-CoV-2. To improve speed of delivery and decrease bedside nursing needs, subcutaneous (SC) delivery of mAbs has been explored as an alternative to standard intravenous (IV) administration. To date, data regarding the effectiveness of SC compared with IV mAb are lacking. This retrospective cohort analysis conducted between April 2021 and August 2021 compared hospitalization rates among patients receiving IV versus SC administration of casirivimab/imdevimab (Regen-COV) at a single institution in Arkansas. Casirivimab/imdevimab was a promising mAb therapy utilized during the height of the Delta variant surge of the SARS-CoV-2 pandemic. Before resistance developed by the Omicron variant, casirivimab/imdevimab was utilized for outpatient treatment of SARS-CoV-2 patients at risk of deterioration. Primary outcomes of this investigation were the 30-day post-treatment rate of hospitalization and intensive care unit (ICU) care during hospitalization. There was no increased risk of hospitalization or ICU care with SC administration compared with IV administration. As SARS-CoV-2 continues to mutate into variants such as Omicron and develop resistance to existing mAbs, these preliminary findings of noninferiority of SC versus IV warrant ongoing investigation into SC administration of other mAbs.

Pandemic Response Requires Research Samples: A U.S. Safety-Net Hospital's Experience and Call for National Action.

Biorepositories provide a critical resource for gaining knowledge of emerging infectious diseases and offer a mechanism to rapidly respond to outbreaks; the emergence of the novel coronavirus, SARS-CoV-2, has proved their importance. During the COVID-19 pandemic, the absence of centralized, national biorepository efforts meant that the onus fell on individual institutions to establish sample repositories. As a safety-net hospital, Boston Medical Center (BMC) recognized the importance of creating a COVID-19 biorepository to both support critical science at BMC and ensure representation in research for its urban patient population, most of whom are from underserved communities. This article offers a realistic overview of the authors' experience in establishing this biorepository at the onset of the COVID-19 pandemic during the height of the first surge of cases in Boston, Massachusetts, with the hope that the challenges and solutions described are useful to other institutions. Going forward, funders, policymakers, and infectious disease and public health communities must support biorepository implementation as an essential element of future pandemic preparedness.

The safety of performing breast reconstruction during the COVID-19 pandemic.

PurposeElective operations including surgeries for breast cancer were significantly reduced during the height of the surge of COVID-19 cases in Massachusetts. The safety of performing breast reconstruction during the pandemic was unknown. This study aims to review the safety of performing mastectomy with immediate breast reconstruction during the first COVID-19 surge in Massachusetts.MethodsA retrospective chart review of patients who underwent mastectomy with immediate breast reconstruction by Massachusetts General Hospital breast and plastic surgeons immediately preceding and during the COVID-19 pandemic was performed.ResultsThirty patients (34 breasts) underwent mastectomies with immediate breast reconstruction during the COVID-19 restriction period in Massachusetts. Most reconstructions were unilateral. All reconstructions were performed with implants or expanders, and no autologous reconstructions were performed. Two patients (2 breasts) had operative complications. The complication rate during the pandemic was similar to the complication rate pre-pandemic. No patients or surgeons experienced symptoms or positive COVID-19 tests. Over 90% of patients were discharged the same day.ConclusionProsthetic breast reconstruction was able to be performed safely during the height of the COVID-19 pandemic surge in Massachusetts. Strict screening protocols, proper use of personal protective equipment, and same-day discharge when possible are essential for patient and surgeon safety during the pandemic.

Lessons from two SARS-CoV-2 waves in South Africa

Lessons from two SARS-CoV-2 waves in South Africa

Engagement in Music-Related Activities During the COVID-19 Pandemic as a Mirror of Individual Differences in Musical Reward and Coping Strategies.

The COVID-19 pandemic and the measures taken to mitigate its impact (e.g., confinement orders) have affected people's lives in profound ways that would have been unimagable only months before the pandemic began. Media reports from the height of the pandemic's initial international surge frequently highlighted that many people were engaging in music-related activities (from singing and dancing to playing music from balconies and attending virtual concerts) to help them cope with the strain of the pandemic. Our first goal in this study was to investigate changes in music-related habits due to the pandemic. We also investigated whether engagement in distinct music-related activities (singing, listening, dancing, etc.) was associated with individual differences in musical reward, music perception, musical training, or emotional regulation strategies. To do so, we collected detailed (~1 h-long) surveys during the initial peak of shelter-in-place order implementation (May–June 2020) from over a thousand individuals across different Countries in which the pandemic was especially devastating at that time: the USA, Spain, and Italy. Our findings indicate that, on average, people spent more time in music-related activities while under confinement than they had before the pandemic. Notably, this change in behavior was dependent on individual differences in music reward sensitivity, and in emotional regulation strategies. Finally, the type of musical activity with which individuals engaged was further associated with the degree to which they used music as a way to regulate stress, to address the lack of social interaction (especially the individuals more concerned about the risk of contracting the virus), or to cheer themselves up (especially those who were more worried about the pandemic consequences). Identifying which music-related activities have been particularly sought for by the population as a means for coping with such heightened uncertainty and stress, and understanding the individual differences that underlie said propensities are crucial to implementing personalized music-based interventions that aim to reduce stress, anxiety, and depression symptoms.

S2845 A Rare Pandemic Presentation: Acute Perforated Duodenal Ulcer in a COVID-19 Case With Acute Abdominal Pain

INTRODUCTION: Gastrointestinal presentations in the novel Covid-19 pandemic include nausea, diarrhea, ischemic colitis, elevated liver enzymes and abdominal pain in 3-4% of cases. Excluding abnormal liver functions at initial presentation, most gastrointestinal symptoms generally portray a favorable prognostic outcome. Ischemic phenomena ostensibly comprise a third of ICU patients with systemic inflammatory response and coagulopathy. Neither serious upper gastrointestinal manifestation [at initial presentation] nor acute peptic ulcer symptoms with associated perforations, with respect to Covid-19, have been noted worldwide. We report such a case. Managed successfully and treated in a conventional manner, with accepted FDA approved therapy for Covid-19. CASE DESCRIPTION/METHODS: A 72 year old female presented to the ED with left upper quadrant pain and chest pain and subsequently discharged after an initial negative CT. 2 days later, at the height of the covid pandemic surge in the NYC area, she presented with worsening of symptoms. Repeat CT revealed free air under her diaphragm and resulted in an emergency laparotomy with an omental patch repair/suturing of acutely perforated duodenal ulcer. Acute febrile status on post op day 4 with myalgias led to a diagnosis of Covid-19 with appropriate PCR testing. Adhering to conventional treatment in the early pandemic wave, she underwent immediate additional therapy with HCQ and Zithromax for 5 days and discarded home on PPIs after full recovery. Her subsequent Covid testing was negative with both IgG and IgM antibody response. Similarly, her stool H.Pylori PCR and her stool Covid PCR were also negative. DISCUSSION: Perforated peptic ulceration, warranting emergent surgery, has not been detailed as an etiology of abdominal pain in Covid-19 patients in the novel Coronavirus pandemic literature. Our case underwent an emergency surgery at the height of the pandemic at a NJ epicenter hospital. Covid-19 positive status was not discovered until post op day 4 as the outcomes for the patient may not have been as fortuitous with known prior diagnosis of Covid-19 in the early pandemic panic atmosphere. Contrasting with respect to other initial gastrointestinal manifestations in Covid, our patient had a favorable outcome while managed successfully and treated conventionally. In future waves of the pandemic, the gastrointestinal community should have a heightened suspicion for complicated acute peptic ulcer disease in Covid-19 patients presenting with acute upper abdominal pain.Figure 1.: Large free intraperitoneal air in the right greater left sub-diaphragmatic area.Figure 2.: Perforated duodenal ulcer with large amount free intraperitoneal air as seen on sagittal plane.

Comparison of the Storm Surge Prediction Models Using Different Atmospheric Forcing for Typhoon CHABA

Kwon, Y.-Y.; Choi, J.-W.; Kim, H.; Kim, S., and Kwon, J.-I., 2019. Comparison of the storm surge prediction models using different atmospheric forcing for typhoon CHABA. In: Lee, J.L.; Yoon, J.-S.; Cho, W.C.; Muin, M., and Lee, J. (eds.), The 3rd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 91, pp. 31-35. Coconut Creek (Florida), ISSN 0749-0208.Typhoon-induced storm surges can cause severe damage on the Korean Peninsula, where typhoons typically occur two or three times per year. In the case of Typhoon MAEMI (0314), a storm surge of 2.1 m was observed at Masan Port, causing $4.8 billion US dollars in property damage. Therefore, the accurate prediction of the storm surge heights and peak times of typhoon surges occurring in the vicinity of the Korean Peninsula is important for minimizing this damage. Two weather models, Weather Research and Forecast (WRF) and Hurricane Weather Research and Forecasting (HWRF) were used to compare storm surges using different atmospheric forcings, and storm surges were calculated using the DElft3D-FM model. By comparing the height and peak time with those of the actual storm, we found that the WRF model results underestimate the actual height and peak time of the typhoon CHABA surge, but the HWRF model is better than the WRF model at predicting the surge height and peak time of the storm surge occurring during typhoon CHABA.

Numerical modeling of the impact of hurricanes on ocean dynamics: sensitivity of the Gulf Stream response to storm’s track

The study is focused on the disruption that a storm can cause to ocean stratification and ocean currents in a region dominated by a western boundary current and meso-scale variability. Sensitivity experiments with a regional numerical ocean model of the US East Coast are used to simulate different hurricane tracks to study the impact on the Gulf Stream (GS) flow, surrounding waters and coastal sea level. Realistic simulations of Hurricane Matthew (October 2016) using surface wind and heat flux from NOAA’s operational coupled forecast system were compared with idealized artificial hurricanes with tracks located at different distances from the coast (~ 200–600 km). Despite the limitation of representing realistic wind patterns by an analytical formula, coastal storm surge near the hurricane was simulated quite well. The height of the coastal storm surge was found to be very sensitive to the location of the hurricane track relative to the coast, but the impact of the hurricane on the GS flow was found to be less sensitive to the exact hurricane track, though the maximum influence was when the hurricane track passed ~ 100 km east of the GS with winds over the GS opposing the current direction. Hurricanes that passed within hundreds of kilometers from the GS caused disruption in the GS dynamics and weakening in the downstream flow of the GS that can last for many days after the storm disappeared. This indirect impact of hurricanes on the GS can elevate sea level along long stretches of the coast. The impact of a hurricane on a region dominated by meso-scale variability is complex, creating unpredictable spatial changes in temperatures and currents. After the hurricane disappeared and without additional surface heating, it may take the stratification as much as 2 months to recover to pre-hurricane conditions by advection alone. This lasting impact of a storm on ocean dynamics is consistent with observations that show minor tidal coastal flooding that lasts for days after hurricanes passed offshore.

Surge Waves Under Earthquake and Clastic Flow Landslide

This paper primarily investigates the surge wave of the barrier lake during an earthquake and clastic flow landslide simultaneously. Earthquakes can trigger clastic flow landslides with strong mobility enabling them to move a significant distance underwater. However, there have been few studies on the simultaneous superposition of seismic surge and clastic flow landslide until this study. First, we designed an experiment to analyze the influence of landslide motion under surging water; then, we investigated the effects of the clastic flow landslide and earthquake on the variation of surge wave height, with large-scale shaking table water tank model experiments. The experimental variables included the initial water depth, peak ground acceleration, landslide impact velocity, and landslide volume. According to the experimental results, we analyzed the maximum wave height under the combined action of an earthquake and clastic flow landslide. Furthermore, we defined a reduction factor of the seismic surge and put forward an equation to predict the reduction factor by means of dimensionless multiple linear fitting analysis. Finally, we present a method for calculating the maximum wave height of the combined surge during both an earthquake and clastic flow landslide using the reduction factor and provide a case to verify the reliability of the formula. Our study could provide the basis for the analysis of the burst of the barrier lake.

Identification of extreme storm surges with high-impact potential along the German North Sea coastline

Planning and design of coastal protection rely on information about the probabilities of very severe storm tides and the possible changes that may occur in the course of climate change. So far, this information is mostly provided in the form of high percentiles obtained from frequency distributions or return values. More detailed information and assessments of events that may cause extreme damages or have extreme consequences at the coast are so far still unavailable. We describe and compare two different approaches that may be used to identify highly unlikely but still physically possible and plausible events from model simulations. Firstly, in the case when consistent wind and tide-surge data are available, different metrics such as the height of the storm surge can be derived directly from the simulated water levels. Secondly, in cases where only atmospheric data are available, the so called effective wind may be used. The latter is the projection of the horizontal wind vector on that direction which is most effective in producing surges at the coast. Comparison of events identified by both methods show that they can identify extreme events but that knowledge of the effective wind alone does not provide sufficient information to identify the highest storm surges. Tracks of the low-pressure systems over the North Sea need to be investigated to find those cases, where the duration of the high wind is too short to induce extreme storm tides. On the other hand, factors such as external surges or variability in mean sea level may enhance surge heights and are not accounted for in estimates based on effective winds only. Results from the analysis of an extended data set suggest that unprecedented storm surges at the German North Sea coast are possible even without taking effects from rising mean sea level into account. The work presented is part of the ongoing project “Extreme North Sea Storm Surges and Their Consequences” (EXTREMENESS) and represents the first step towards an impact assessment for very severe storm surges which will serve as a basis for development of adaptation options and evaluation criteria.

Examining the Effects of Objective Hurricane Risks and Community Resilience on Risk Perceptions of Hurricanes at the County Level in the U.S. Gulf Coast: An Innovative Approach

Communities' risk perceptions can influence their abilities to cope with coastal hazards such as hurricanes and coastal flooding. Our study presents an initial effort to examine the relationship between community resilience and risk perception at the county level, through innovative construction of aggregate variables. Using the 2012 Gulf Coast Climate Change Survey merged with historical hurricane data and community resilience indicators, we first apply a spatial statistical model to construct a county-level risk perception indicator based on survey responses. Next, we employ regression to reveal the relationship between contextual hurricane risk factors and community resilience on one hand and county-level perceptions of hurricane risks on the other. Results of this study are directly applicable in the policymaking domain as many hazard mitigation plans and adaptation policies are designed and implemented at the county level. Specifically, two major findings stand out. First, the contextual hurricane risks represented by peak height of storm surge associated with the last hurricane landfall and land area exposed to historical storm surge flooding positively affect county-level risk perceptions. This indicates that another threat of hurricanes—wind risks—needs to be clearly communicated with the public and fully incorporated into hazard mitigation plans and adaptation policies. Second, two components of community resilience—higher levels of economic resilience and community capital—are found to lead to heightened perceptions of hurricane risks, which suggests that concerted efforts are needed to raise awareness of hurricane risks among counties with less economic and community capital.

Influence of surge movement in non-uniform water flow on performance of underwater quantum communication

Quantum communication is brand new way of communication in which quantum entanglement is used to transmit information. It is an interdisciplinary subject combining quantum informatics with modern communication theory. Motivated by the communication requirements for underwater sensor networks, submarines, etc., underwater optical communication has been developing rapidly in recent years due to the ideal information security of quantum communication. However, the research on the performance of underwater quantum communication in sea has not yet been fully developed because of a series of factors such as surge, salinity and seaweed and so on. In this paper, the influence of surge in non-uniform water flow on the underwater quantum communication is studied theoretically and experimentally. Firstly, a new Boussinesq equation with a given flow function is derived based on the horizontal and vertical wave velocity of the free surface to represent the free surface boundary conditions. On the other hand, In view of the nonlinear motion of movement, the complexity of change and the randomness of the distribution, the spectrum is used for numerically calculating the surge. The characteristics of wave motion are described by wave height, period and wavelength. Secondly, the influence of surge on the entanglement of underwater quantum channel is analyzed. It is proved that the wave height of surge and the change of the cycle affect quantum communication due to the destruction of the quantum coherence and the reduction in quantum entanglement degree. Thirdly, the influence of surge motion on the quantum channel capacity is studied. The influence of the relation between the wavelength and the transmission cycle on the quantum channel capacity is simulated. The relationship between the physical characteristics of surge wave and the capacity of depolarized channel is established. Fourthly, the influence of surge motion on error rate in quantum key distribution is studied. The simulation results show that when the sea surface wind speed changes in a range of 0-20.5 m/s, the propagation cycle is increased gradually. The channel entanglement is increased from 0.0012 to 0.8426, and the channel capacity is reduced from 0.8736 to 0.1024. In the key distribution process, the quantum bit error rate increases from 0.1651 to 0.4812. Therefore, in underwater quantum communication, the parameters of the system should be adjusted adaptively according to the varying degree of the surge movement.

Understanding Hurricane Evacuation Decisions Under Contingent Scenarios: A Stated Preference Approach

We conduct a stated preference analysis to understand the factors that individual households take into consideration to evacuate during hurricanes. In designing the contingent scenarios for evacuation, we randomly assign varying levels of hurricane characteristics (wind speed, lead time for landfall and the height of storm surge) combined with different types of emergency management options (voluntary versus mandatory evacuation order and a voucher with varying amounts to cover evacuation expenses). Findings indicate that individual households respond, in a non-linear fashion, to the intensity of hurricanes when making evacuation decisions. Respondents are also more likely to evacuate when the storm surge reaches a certain threshold. In terms of policy interventions, mandatory evacuation orders are more effective to increase the likelihood of evacuation. The potential intervention in the form of providing evacuation vouchers to assist households to cover their expenses (e.g. for food, water, transportation and lodging) also seems effective. We discuss policy implications of our findings.