Realistic Design Waves for Wave-in-Deck Problems

Author(s):  
Arne Bøckmann ◽  
Odin Gramstad ◽  
Jens Bloch Helmers ◽  
Øystein Lande

Due to subsidence, unrealistic environmental assumptions in design or other factors, many fixed offshore installations around the world are prone to large impact forces on the super-structure. Too often, unexpected damages are found, and more accurate analyses reveal the need for reinforcement to comply with the relevant rules and regulations. The common analytical practice is to compute impact forces using 5th order Stokes waves in a CFD solver, with the crest height set to the relevant return period. Using this approach implicitly introduces a series of unrealistic assumptions, and cannot necessarily be expected to produce the force of the desired return period. In the present work, we propose a framework to better estimate the true waves producing the 100-year wave-in-deck forces in a typical North Sea environment. This is done by a long-term analysis of wave-in-deck force, hierarchically using several screening filters and solvers of different complexity. The main facilitator is an efficient High-Order Spectral Method, which at the final level is used as initial and boundary conditions in CFD. The resulting waves are short crested and may break — producing very high crest velocities that are normally not accounted for in standard engineering practice.

Author(s):  
Omar Hashim Thanon

Since peaceful coexistence reflects in its various aspects the concept of harmony between the members of the same society with their different national, religious and sectarian affiliations, as well as their attitudes and ideas, what brings together these are the common bonds such as land, interests and common destiny. But this coexistence is exposing for crises and instability and the theft of rights and other that destroy the communities with their different religious, national, sectarian, ethnic aspects, especially if these led to a crisis of fighting or war, which produces only destruction and mass displacement, ttherefore, the process of bridging the gap between the different parts of society in the post-war phase through a set of requirements that serve as the basis for the promotion of peaceful coexistence within the same country to consolidate civil and community peace in order to create a general framework and a coherent basis to reconstruct the community again.      Hence the premise of the research by asking about the extent of the possibility and ability of the community of religious and ethnic diversity, which has been exposed to these crises, which aimed at this diversity, basically to be able to rise and re-integrate within the same country and thus achieve civil and community peace, and Mosul is an example for that, the negative effects of the war and the accomplices of many criminal acts have given rise to hatred and fear for all, leading to the loss of livelihoods, which in the long term may have devastating social and psychological consequences.        To clarify all of this, the title of the first topic was a review of the concept and origin of peaceful coexistence. While the second topic dealt with the requirements of peaceful coexistence and social integration in Mosul, the last topic has identified the most important challenges facing the processes of coexistence and integration in Mosul. All this in order to paint a better future for the conductor at all levels in the near term at the very least to achieve the values of this peaceful coexistence, especially in the post-war period.


Author(s):  
Ekaterina Shchurova ◽  
Ekaterina Shchurova ◽  
Rimma Stanichnaya ◽  
Rimma Stanichnaya ◽  
Sergey Stanichny ◽  
...  

Sivash bay is the shallow-water lagoon of the Azov Sea. Restricted water exchange and high evaporation form Sivash as the basin with very high salinity. This factor leads to different from the Azov Sea thermal and ice regimes of Sivash. Maine aim of the study presented to investigate recent state and changes of the characteristics and processes in the basin using satellite data. Landsat scanners TM, ETM+, OLI, TIRS together with MODIS and AVHRR were used. Additionally NOMADS NOAA and MERRA meteorological data were analyzed. The next topics are discussed in the work: 1. Changes of the sea surface temperature, ice regime and relation with salinity. 2. Coastal line transformation – long term and seasonal, wind impact. 3. Manifestation of the Azov waters intrusions through the Arabat spit, preferable wind conditions.


Author(s):  
Paolo Giamundo

Background: Minimally-invasive treatments for hemorrhoids should be encouraged as they cause low morbidity, reasonable discomfort and quicker return to work. According to the “vascular theory” hemorrhoidal disease is mainly caused by blood overflow into hemorrhoidal plexus deriving from the superior hemorrhoidal arteries. Introduction: Many different procedures have been described in the literature with the common goal of reducing the blood flow into the hemorrhoidal piles. ‘HeLP’ (Hemorrhoids Laser Procedure) is a novel form of dearterialization to treat patients suffering from symptomatic hemorrhoids. Methods: The procedure consists of the closure of the terminal branches of the superior rectal artery approximately 2-3 cm above the dentate line by means of laser shots originated by a diode laser platform. The arteries, at that level, have variable location and distribution. Therefore, a doppler probe set at the frequency of 20MHz helps identifying the arteries that would be missed otherwise. The laser beam is well tolerated by patients. For this reason, anesthesia is not required in most cases and the procedure allows a quick return to daily activities. In case of concomitant severe mucosal prolapse, the laser treatment can be combined with suture mucopexy. Three to six running sutures allow a complete lifting of hemorrhoidal piles, securing long-term resolution of symptoms. Results and Conclusions: ‘HeLP’ is indicated in patients with symptomatic hemorrhoids where conservative treatment failed and when mucosal prolapse is scarce or not symptomatic. The addition of mucopexy to laser treatment (HeLPexx) contributes to overall resolution of symptoms when mucosal prolapse is an issue, Emborrhoid is another novel, ‘hi-tech’ form of selective dearterialization used in selected case of hemorrhoids where main symptom is bleeding. It is generally used in cases where surgery is contraindicated due to severe concomitant diseases.


Author(s):  
Jill C. Fodstad ◽  
Rebecca Elias ◽  
Shivali Sarawgi

Gender diversity refers to gender expressions and/or gender identity experiences that vary from the common experiences of gender. Gender-diverse people may be gender nonconforming, gender nonbinary, gender fluid, gender exploring, transgender, and so forth. Some gender-diverse individuals experience gender dysphoria and/or gender incongruence and may require gender-affirming supports, including gender-affirming medical interventions. The co-occurrence of autism and gender diversity has been highlighted in a series of studies internationally as well as through rich community expressions. Studies in gender-referred individuals reveal high rates of autism traits as well as high rates of existing autism diagnoses. Studies in autistic populations reveal greater gender diversity characteristics. The long-term course of gender diversity in autistic individuals is poorly understood. Clinical guidelines have been developed for adolescents with the co-occurrence, but much work remains: No gender-related measures have been developed and tested for use in neurodiverse populations, no programs exist to support gender-diverse neurodiverse adults, and little is known about co-occurring mental health profiles, risks, or protective factors for people with the co-occurrence. The inclusion of this chapter on co-occurring autism and gender diversity within a book on “co-occurring psychiatric conditions” is problematic, because gender diversity is not a “psychiatric condition,” but instead a form of human diversity. The diagnosis of Gender Dysphoria is useful only insomuch as it allows individuals to obtain necessary gender-related supports. The authors’ choice to include this chapter in this book reflects a compromise, motivated by the need for educating both autism and gender specialists in this common co-occurrence.


Author(s):  
Michael A. Cohn ◽  
Barbara L. Fredrickson

Positive emotions include pleasant or desirable situational responses, ranging from interest and contentment to love and joy, but are distinct from pleasurable sensation and undifferentiated positive affect. These emotions are markers of people's overall well-being or happiness, but they also enhance future growth and success. This has been demonstrated in work, school, relationships, mental and physical health, and longevity. The broaden-and-build theory of positive emotions suggests that all positive emotions lead to broadened repertoires of thoughts and actions and that broadening helps build resources that contribute to future success. Unlike negative emotions, which are adapted to provide a rapid response to a focal threat, positive emotions occur in safe or controllable situations and lead more diffusely to seeking new resources or consolidating gains. These resources outlast the temporary emotional state and contribute to later success and survival. This chapter discusses the nature of positive emotions both as evolutionary adaptations to build resources and as appraisals of a situation as desirable or rich in resources. We discuss the methodological challenges of evoking positive emotions for study both in the lab and in the field and issues in observing both short-term (“broaden”) and long-term (“build”) effects. We then review the evidence that positive emotions broaden perception, attention, motivation, reasoning, and social cognition and ways in which these may be linked to positive emotions' effects on important life outcomes. We also discuss and contextualize evidence that positive emotions may be detrimental at very high levels or in certain situations. We close by discussing ways in which positive emotions theory can be harnessed by both basic and applied positive psychology research.


Biology ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 522
Author(s):  
Régis Santos ◽  
Wendell Medeiros-Leal ◽  
Osman Crespo ◽  
Ana Novoa-Pabon ◽  
Mário Pinho

With the commercial fishery expansion to deeper waters, some vulnerable deep-sea species have been increasingly captured. To reduce the fishing impacts on these species, exploitation and management must be based on detailed and precise information about their biology. The common mora Mora moro has become the main deep-sea species caught by longliners in the Northeast Atlantic at depths between 600 and 1200 m. In the Azores, landings have more than doubled from the early 2000s to recent years. Despite its growing importance, its life history and population structure are poorly understood, and the current stock status has not been assessed. To better determine its distribution, biology, and long-term changes in abundance and size composition, this study analyzed a fishery-dependent and survey time series from the Azores. M. moro was found on mud and rock bottoms at depths below 300 m. A larger–deeper trend was observed, and females were larger and more abundant than males. The reproductive season took place from August to February. Abundance indices and mean sizes in the catch were marked by changes in fishing fleet operational behavior. M. moro is considered vulnerable to overfishing because it exhibits a long life span, a large size, slow growth, and a low natural mortality.


2021 ◽  
pp. 036354652110101
Author(s):  
Benjamin F.H. Ang ◽  
P. Chandra Mohan ◽  
Meng Ai Png ◽  
John Carson Allen ◽  
Tet Sen Howe ◽  
...  

Background: In a study from our institution, ultrasonic percutaneous tenotomy of the brevis and the common extensor tendon for recalcitrant lateral elbow tendinopathy showed excellent safety profiles, high tolerability, efficiency, sustained pain relief, functional improvement, and sonographic evidence of tissue healing in 20 patients at 3 years’ follow-up. Purpose: To explore the long-term clinical and sonographic results of ultrasonic percutaneous tenotomy of the brevis and the common extensor tendon. Study Design: Case series; Level of evidence, 4. Methods: The same cohort of 20 patients was recalled after 7 years, and visual analog scale (VAS) for pain and Disabilities of the Arm, Shoulder and Hand (DASH) scores, need for secondary intervention, and overall satisfaction were assessed. They were also reassessed using ultrasound imaging of the brevis and the common extensor tendon to evaluate tendon hypervascularity, tendon thickness, and the progress or the recurrence of the hypoechoic scar tissue. Results: We successfully scored 19 patients and performed ultrasound on 16 patients with a median follow-up of 90 months (range, 86-102 months). There were no adverse outcomes and satisfaction remained at 100% (6 patients, satisfied; 13 patients, very satisfied). No patient developed a recurrence of symptoms and signs of lateral elbow tendinopathy, and therefore no secondary intervention was required. The improvement from baseline and early term scores was sustained ( P < .001 for all). At 90 months, there was a significant improvement in VAS scores and DASH–Compulsory scores compared with preprocedure scores and all follow-up times until 3 months. There was no difference in VAS scores and DASH–Compulsory scores at 90 months compared with 6 and 36 months. For DASH–Work scores, there was a significant improvement at 90 months compared with preprocedure scores, but there was no difference between DASH–Work scores at 90 months and scores at all other points of follow-up. At 90 months, hypervascularity remained resolved in 79% of patients, while all patients had reduced tendon swelling and sustained resolution or reduction of the hypoechoic lesion. Conclusion: At the long-term follow-up of 90 months, ultrasonic percutaneous tenotomy of the brevis and the common extensor tendon, previously shown to enhance recovery of lateral elbow tendinopathy, demonstrated good durability of pain relief and functional recovery that was previously achieved. This was accompanied by sustained sonographic tissue healing with no significant deterioration.


Author(s):  
Thomas L Rodebaugh ◽  
Madelyn R Frumkin ◽  
Angela M Reiersen ◽  
Eric J Lenze ◽  
Michael S Avidan ◽  
...  

Abstract Background The symptoms of COVID-19 appear to be heterogenous, and the typical course of these symptoms is unknown. Our objectives were to characterize the common trajectories of COVID-19 symptoms and assess how symptom course predicts other symptom changes as well as clinical deterioration. Methods 162 participants with acute COVID-19 responded to surveys up to 31 times for up to 17 days. Several statistical methods were used to characterize the temporal dynamics of these symptoms. Because nine participants showed clinical deterioration, we explored whether these participants showed any differences in symptom profiles. Results Trajectories varied greatly between individuals, with many having persistently severe symptoms or developing new symptoms several days after being diagnosed. A typical trajectory was for a symptom to improve at a decremental rate, with most symptoms still persisting to some degree at the end of the reporting period. The pattern of symptoms over time suggested a fluctuating course for many patients. Participants who showed clinical deterioration were more likely to present with higher reports of severity of cough and diarrhea. Conclusion The course of symptoms during the initial weeks of COVID-19 is highly heterogeneous and is neither predictable nor easily characterized using typical survey methods. This has implications for clinical care and early-treatment clinical trials. Additional research is needed to determine whether the decelerating improvement pattern seen in our data is related to the phenomenon of patients reporting long-term symptoms, and whether higher symptoms of diarrhea in early illness presages deterioration.


2021 ◽  
pp. 002029402110130
Author(s):  
Xian Wang ◽  
Qian-cheng Zhao ◽  
Xue-bing Yang ◽  
Bing Zeng

The historical temperature data logged in the supervisory control and data acquisition (SCADA) system contains a wealth of information that can assist with the performance optimization of wind turbines (WTs). However, mining and using these long-term data is difficult and time-consuming due to their complexity, volume, etc. In this study, we tracked and analyzed the 5-year trends of major SCADA temperature rise variables in relation to the active power of four WTs in a real wind farm. To uncover useful information, an extended version of the bins method, which calculates the standard deviation (SD) as well as the average, is proposed and adopted. The implications of the analysis for engineering practice are discussed from multiple perspectives. The research results demonstrate a change in the patterns of the main temperature rise variables in a real wind farm, completeness of the monitoring of the WT internal temperature state, influence of wind turbine aging on temperature signals, a correlation between different measurement points, and a correlation between signals from different years. The knowledge gained from this research provides a reference for the development of more practical and comprehensive condition monitoring systems and methods, as well as better operation maintenance strategies.


2021 ◽  
Vol 127 (8) ◽  
Author(s):  
R. Radhakrishnan Sumathi

AbstractAluminium nitride (AlN) is a futuristic material for efficient next-generation high-power electronic and optoelectronic applications. Sublimation growth of AlN single crystals with hetero-epitaxial approach using silicon carbide substrates is one of the two prominent approaches emerged, since the pioneering crystal growth work from 1970s. Many groups working on this hetero-epitaxial seeding have abandoned AlN growth altogether due to lot of persistently encountered problems. In this article, we focus on most of the common problems encountered in this process such as macro- and micro-hole defects, cracks, 3D-nucleation, high dislocation density, and incorporation of unintentional impurity elements due to chemical decomposition of the substrate at very high temperatures. Possible ways to successfully solve some of these issues have been discussed. Other few remaining challenges, namely low-angle grain boundaries and deep UV optical absorption, are also presented in the later part of this work. Particular attention has been devoted in this work on the coloration of the crystals with respect to chemical composition. Wet chemical etching gives etch pit density (EPD) values in the order of 105 cm-2 for yellow-coloured samples, while greenish coloration deteriorates the structural properties with EPD values of at least one order more.


Sign in / Sign up

Export Citation Format

Share Document