scholarly journals VESSEL-INDUCED SURGE MODEL VALIDATION IN A COMPLEX HARBOR USING FIELD MEASUREMENTS AND AIS DATA

2018 ◽  
pp. 52
Author(s):  
Francis Salcedo ◽  
Abhishek Sharma ◽  
Scott Fenical ◽  
Gary Ledford
Keyword(s):  
Model Validation ◽  
Laboratory Data ◽  
Field Measurements ◽  
Open Water ◽  
Limited Information ◽  
Marine Habitat ◽  
Practical Applications ◽  
Quay Wall ◽  
Complex Phenomena ◽  
Seiche Oscillations

Large ships moving in narrow waterways generate complex hydrodynamic phenomena, which can cause extreme forces and moments on berthed vessels, and damage shoreline structures and marine habitat. Deep-draft vessels can generate complex phenomena such as bow solitary waves, broken supercritical bore waves, and ship-induced harbor seiche/oscillations. Particular focus is paid in the present paper to simulation and validation of the Vessel Hydrodynamics Longwave Unsteady (VH-LU) modeling system (Fenical et al. 2006) for these complex hydrodynamic phenomena, in particular sloshing and resonance of vessel-induced waves in the complex harbor of Port Canaveral, FL. This paper summarizes two field measurement campaigns and utilization of high-resolution AIS data to provide detailed input for model validation. Analysis indicates that the modeling system is able to reproduce water level oscillations generated by individual vessels, oscillation interactions within the harbor, and interactions between separate basins in the harbor over time. Previous publications have provided limited information on validations performed with the VH-LU modeling system (e.g. Fenical et al. 2011). The model has been shown to accurately reproduce hydrodynamics and berthed vessel forces on tankers in open water conditions, hydrodynamics and loads on berthed Panamax container ships against a vertical quay wall, and supercritical flow and broken bore formation and propagation. This paper will summarize the complete range of model validations with the highest-quality openly available laboratory data, and provide recommendations for future studies and research based on observed needs from practical applications.

scholarly journals Risk of cardiac manifestations in adult mitochondrial disease caused by nuclear genetic defects

Open Heart ◽  
2021 ◽  
Vol 8 (1) ◽  
pp. e001510
Author(s):  
Albert Zishen Lim ◽  
Daniel M Jones ◽  
Matthew G D Bates ◽  
Andrew M Schaefer ◽  
John O'Sullivan ◽  
...  
Keyword(s):  
Mitochondrial Disease ◽  
Nuclear Dna ◽  
Laboratory Data ◽  
Nuclear Genome ◽  
Nuclear Gene ◽  
Left Ventricular ◽  
Adult Patients ◽  
Limited Information ◽  
Cardiac Abnormalities ◽  
Cardiac Manifestations

ObjectiveRegular cardiac surveillance is advocated for patients with primary mitochondrial DNA disease. However, there is limited information to guide clinical practice in mitochondrial conditions caused by nuclear DNA defects. We sought to determine the frequency and spectrum of cardiac abnormalities identified in adult mitochondrial disease originated from the nuclear genome.MethodsAdult patients with a genetically confirmed mitochondrial disease were identified and followed up at the national clinical service for mitochondrial disease in Newcastle upon Tyne, UK (January 2009 to December 2018). Case notes, molecular genetics reports, laboratory data and cardiac investigations, including serial electrocardiograms and echocardiograms, were reviewed.ResultsIn this cohort-based observational study, we included 146 adult patients (92 women) (mean age 53.6±18.7 years, 95% CI 50.6 to 56.7) with a mean follow-up duration of 7.9±5.1 years (95% CI 7.0 to 8.8). Eleven different nuclear genotypes were identified: TWNK, POLG, RRM2B, OPA1, GFER, YARS2, TYMP, ETFDH, SDHA, TRIT1 and AGK. Cardiac abnormalities were detected in 14 patients (9.6%). Seven of these patients (4.8%) had early-onset cardiac manifestations: hypertrophic cardiomyopathy required cardiac transplantation (AGK; n=2/2), left ventricular (LV) hypertrophy and bifascicular heart block (GFER; n=2/3) and mild LV dysfunction (GFER; n=1/3, YARS2; n=1/2, TWNK; n=1/41). The remaining seven patients had acquired heart disease most likely related to conventional cardiovascular risk factors and presented later in life (14.6±12.8 vs 55.1±8.9 years, p<0.0001).ConclusionsOur findings demonstrate that the risk of cardiac involvement is genotype specific, suggesting that routine cardiac screening is not indicated for most adult patients with nuclear gene-related mitochondrial disease.

Estimating the Effects of Urban Street Incidents on Capacity

2017 ◽  
Vol 2615 (1) ◽  
pp. 55-61 ◽  
Author(s):  
Aidin Massahi ◽  
Mohammed Hadi ◽  
Maria Adriana Cutillo ◽  
Yan Xiao
Keyword(s):  
Network Performance ◽  
Field Measurements ◽  
Signalized Intersection ◽  
Limited Information ◽  
Microscopic Simulation ◽  
Highway Capacity ◽  
Highway Capacity Manual ◽  
Urban Streets ◽  
Urban Street ◽  
Incident Duration

The effect of incidents on capacity is the most critical parameter in estimating the influence of incidents on network performance. The Highway Capacity Manual 2010 (HCM 2010) provides estimates of the drop in capacity resulting from incidents as a function of the number of blocked lanes and the total number of lanes in the freeway section. However, there is limited information on the effects of incidents on the capacity of urban streets. This study investigated the effects on capacity of the interaction between the drop in capacity below demand at a midblock urban street segment location and upstream and downstream of signalized intersection operations. A model was developed to estimate the drop in capacity at the incident location as a function of the number of blocked lanes, the distance from the downstream intersection, and the green time–to–cycle length (g:C) ratio of the downstream signal. A second model was developed to estimate the reduction in the upstream intersection capacity resulting from the drop in capacity at the midblock incident location as estimated by the first model. The second model estimated the drop in capacity of the upstream links feeding the incident locations as a function of incident duration time, the volume-to-capacity (V/C) ratio at the incident location, and distance from an upstream signalized intersection. The models were developed on the basis of data generated with the use of a microscopic simulation model calibrated by comparison with parameters suggested in HCM 2010 for incident and no-incident conditions and by comparison with field measurements.

Assessment of Moisture Content in Sandy Beach Environments from Multispectral Satellite Imagery

2021 ◽  
Author(s):  
Julie Paprocki ◽  
Nina Stark ◽  
Hans C Graber ◽  
Heidi Wadman ◽  
Jesse E McNinch
Keyword(s):  
Moisture Content ◽  
Laboratory Data ◽  
Field Measurements ◽  
Weather Conditions ◽  
Sandy Beaches ◽  
Percent Error ◽  
Moisture Contents ◽  
Multispectral Satellite Imagery ◽  
Factor C

A framework for estimating moisture content from satellite-based multispectral imagery of sandy beaches was tested under various site conditions and sensors. It utilizes the reflectance of dry soil and an empirical factor c relating reflectance and moisture content for specific sediment. Here, c was derived two ways: first, from in-situ measurements of moisture content and average NIR image reflectance; and second, from laboratory-based measurements of moisture content and spectrometer reflectance. The proposed method was tested at four sandy beaches: Duck, North Carolina, and Cannon Beach, Ocean Cape, and Point Carrew, Yakutat, Alaska. Both measured and estimated moisture content profiles were impacted by site geomorphology. For profiles with uniform slopes, moisture contents ranged from 3.0%-8.0% (Zone 1) and from 8.0%-23.0% (Zone 2). Compared to field measurements, the moisture contents estimated using c calibrated from in-situ and laboratory data resulted in percent error of 3.6%-44.7% and 2.7%-58.6%, respectively. The highest percent error occurred at the transition from Zone 1 to Zone 2. Generally, moisture contents were overestimated in Zone 1 and underestimated in Zone 2, but followed the expected trends based on field measurements. When estimated moisture contents in Zone 1 exceeded 10%, surface roughness, debris, geomorphology, and weather conditions were considered.

scholarly journals On contribution of horizontal and intra-layer convection to the formation of the Baltic Sea cold intermediate layer

2008 ◽  
Vol 5 (4) ◽  
pp. 581-623
Author(s):  
I. P. Chubarenko ◽  
N. Y. Demchenko
Keyword(s):  
Baltic Sea ◽  
Intermediate Layer ◽  
Heat Content ◽  
Field Measurements ◽  
Open Water ◽  
Early Spring ◽  
Cold Intermediate Layer ◽  
The Baltic Sea ◽  
The Baltic ◽  
Fast Increase

Abstract. Seasonal cascades down the coastal slopes and intra-layer convection are considered as the two mechanisms contributing to the Baltic Sea cold intermediate layer (CIL) formation. On the base of TS-diagrams, mean-annual and real-time temperature profiles, the CIL features are re-analyzed. The presence within the CIL of water with temperature below that of maximum density (Tmd) and that at the local surface allows tracing its formation. Field measurements are presented, showing specific features of denser water formation in marine environment. It is argued that such cascades formed during early spring heating (March–April) – before reaching the Tmd – are the source of the coldest waters of the CIL. Fast increase of the open water heat content during further spring heating indicates that horizontal exchange rather than direct solar heating is responsible for that. When the surface is covered with water, heated above the Tmd, the conditions within the CIL become favorable for intralayer convection due to the presence of waters of Tmd in intermediate layer, which can explain the observed increase of its salinity and deepening with time.

Detecting subsurface interfaces with a physics-based level-set segmentation and additional geological constraints

2020 ◽  
Author(s):  
Florian Wellmann ◽  
Benjamin Berkels
Keyword(s):  
Level Set ◽  
Gradient Flow ◽  
Field Measurements ◽  
Specific Method ◽  
State Variables ◽  
Image Domain ◽  
Practical Applications ◽  
Level Set Function ◽  
Geological Information ◽  
Geological Constraints

&lt;p&gt;Sharp interfaces often separate regions in the subsurface with distinctively&amp;#160;different properties due to processes in geological evolution &amp;#8211; and these&amp;#160;&amp;#160; interfaces are relevant for a variety of scientific investigations, as well as&amp;#160;practical applications.&amp;#160;&amp;#160;The delineation of these layers with different properties is commonly attempted&amp;#160;on the basis of geological and geophysical data, for example as picks in&amp;#160;&amp;#160;prevalent seismic reflectors, interpreted from potential field measurements,&amp;#160;and derived from observations in drillholes.&amp;#160;&lt;/p&gt;&lt;p&gt;We evaluate here a specific method to determine the position and shape of such&amp;#160;an interface using measurements of state variables related to a physical flow&amp;#160;field described with an elliptic PDE. A typical example is the measurement of&amp;#160;temperatures related to heat flow through zones with distinctively different&amp;#160;thermal conductivities. We use a level-set function to describe the interface&amp;#160;and determine the optimal interface shape for a 2-D case. This type of shape inversion has&amp;#160;been successfully attempted before, and we extend on this previous work by&amp;#160;including additional shape constraints on orientation, interface, and&amp;#160;observations of specific segmentation outcomes. These constrains are motivated&amp;#160;by geological information that may be available, for example as derived and&amp;#160;interpreted from additional geophysical measurements.&amp;#160;&lt;/p&gt;&lt;p&gt;We model this as an image segmentation problem, where we are looking for a&amp;#160;segmentation of the image domain whose induced temperature minimizes the&amp;#160;squared &lt;em&gt;L&lt;sup&gt;2&lt;/sup&gt;&lt;/em&gt; distance to temperature measurements on a lower dimensional set.&amp;#160;From an optimal control perspective, the segmentation is the control and the&amp;#160;temperature the state. &amp;#160;Numerically, the segmentation is represented by a&amp;#160;level set and the minimization is done using a gradient flow, where the&amp;#160;derivative with respect to the level set is computed using dualization.&amp;#160;Moreover, we include additional geologically motivated constraints by adding&amp;#160;soft penalties to the objective function.&lt;/p&gt;&lt;p&gt;We test our method with several conceptual examples to determine the&amp;#160;feasibility and limitations, especially with regard to different interface&amp;#160;shapes and the amount of available information and additional geological&amp;#160;constraints, as well as the influence of noise on the detection&amp;#160;&amp;#160;accuracy. Results show that these additional constraints help determining an&amp;#160;interface. However, measurement noise and a non-homogeneous spatial&amp;#160;distribution of physical properties reduces the accuracy of the derived&amp;#160;interface.&amp;#160;&lt;/p&gt;

Inherent biological variation and reference values

2004 ◽  
Vol 42 (7) ◽  
Author(s):  
Callum G. Fraser
Keyword(s):  
Reference Values ◽  
Laboratory Data ◽  
Population Based ◽  
Biological Variation ◽  
Specific Reference ◽  
Theoretical Concepts ◽  
Practical Applications ◽  
Medical Laboratories ◽  
Clinical Purpose ◽  
Traditional Population

AbstractThere is a need for revisiting theoretical concepts and practical applications of conventional population-based reference values to make for better clinical use of laboratory data. Knowledge of the underlying biological variation of quantities examined in medical laboratories is vital to understanding the proper generation and application of traditional population-based reference values. Appreciation of the biological changes that occur over the span of life is a necessary prerequisite to deciding whether stratification of reference values according to age is likely to be necessary. Knowledge of the detail of predictable biological cyclical rhythms is required for correct clinical interpretation of laboratory data and appropriate collection of specimens at times relevant to the clinical purpose. Quantitative data on inherent within- and between-subject biological components of variation have shown the marked individuality of most quantities of interest in laboratory medicine. This individuality casts light on why examinations are not generally very successfully applied in population screening or case-finding. Consideration of individuality demonstrates why stratification of reference values is often very advantageous. Individuality provides an indisputable argument for better use of individual specific reference values.

A Combined Analytical and Numerical Approach to Analyze Mud Motor Excited Vibrations in Drilling Systems

2015 ◽  
Author(s):  
Andreas Hohl ◽  
Carsten Hohl ◽  
Christian Herbig
Keyword(s):  
Finite Element ◽  
Analytical Model ◽  
Field Measurements ◽  
Element Model ◽  
Numerical Approach ◽  
Analytical Models ◽  
Finite Element Models ◽  
Beam Model ◽  
Direct Influence ◽  
Practical Applications

Severe vibrations in drillstrings and bottomhole assemblies can be caused by cutting forces at the bit or mass imbalances in downhole tools. One of the largest imbalances is related to the working principle of the so-called mud motor, which is an assembly of a rotor that is maintained by the stator. One of the design-related problems is how to minimize vibrations excited by the mud motor. Simulation tools using specialized finite element methods (FEM) are established to model the mechanical behavior of the structure. Although finite element models are useful for estimating rotor dynamic behavior and dynamic stresses of entire drilling systems they do not give direct insight how parameters affect amplitudes and stresses. Analytical models show the direct influence of parameters and give qualitative solutions of design related decisions. However these models do not provide quantitative numbers for complicated geometries. An analytical beam model of the mud motor is derived to calculate the vibrational amplitudes and capture basic dynamic effects. The model shows the direct influence of parameters of the mud motor related to the geometry, material properties and fluid properties. The analytical model is compared to the corresponding finite element model. Vibrational amplitudes are discussed for different modes and parameter changes. Finite element models of the entire drilling system are used to verify the findings from the analytical model using practical applications. The results are compared to time domain and statistical data from laboratory and field measurements.

scholarly journals Atmospheric observations of the water vapour continuum in the near-infrared windows between 2500–6600 cm<sup>−1</sup>

2019 ◽  
Author(s):  
Jonathan Elsey ◽  
Marc D. Coleman ◽  
Tom D. Gardiner ◽  
Kaah P. Menang ◽  
Keith P. Shine
Keyword(s):  
Water Vapour ◽  
Near Infrared ◽  
Laboratory Data ◽  
Field Measurements ◽  
The Self ◽  
Atmospheric Conditions ◽  
Sensing Applications ◽  
Atmospheric Observations ◽  
Real Atmosphere ◽  
Remote Sensing Applications

Abstract. Water vapour continuum absorption is potentially important for both closure of the Earth’s energy budget and remote sensing applications. Currently, there are significant uncertainties in its characteristics in the near-infrared atmospheric windows at 2.1 and 1.6 μm. There have been several attempts to measure the continuum in the laboratory; not only are there significant differences amongst these measurements but there are also difficulties in extrapolating the laboratory data taken at room temperature or higher to atmospheric temperatures. Validation is therefore required using field observations of the real atmosphere. There are currently few published observations in atmospheric conditions with enough water vapour to detect a continuum signal within these windows, or where the self-continuum component is significant. We present observations of the near-infrared water vapour continuum from Camborne, UK at sea level using a sun-pointing, radiometrically-calibrated Fourier transform spectrometer in the window regions between 2000–10000 cm−1. Analysis of this data is challenging, particularly because of the need to remove aerosol extinction, and the large uncertainties associated with such field measurements. Nevertheless, we present data that is consistent with recent laboratory datasets in the 4 and 2.1 μm windows (when extrapolated to atmospheric temperatures). These results indicate that the most recent revision (3.2) of the MT_CKD foreign continuum, versions of which are widely used in atmospheric radiation models, requires strengthening by a factor of ~ 5 in the centre of the 2.1 µm window. In the higher-wavenumber window at 1.6 µm, our estimated self and foreign continua are significantly stronger than MT_CKD. The possible contribution of the self and foreign continua to our derived total continuum optical depth is estimated by using laboratory or MT_CKD values of one, to estimate the other. The obtained self-continuum shows some consistency with temperature-extrapolated laboratory data in the centres of the 4 and 2.1 µm windows. The 1.6 μm region is more sensitive to atmospheric aerosol and continuum retrievals and therefore more uncertain than the more robust results at 2.1 and 4 μm. We highlight the difficulties in observing the atmospheric continuum and make the case for additional measurements from both the laboratory and field, with discussion of the requirements for any new field campaign.

scholarly journals A Novel Subspace Alignment-Based Interference Suppression Method for the Transfer Caused by Different Sample Carriers in Electronic Nose

Sensors ◽  
2019 ◽  
Vol 19 (22) ◽  
pp. 4846 ◽  
Author(s):  
Zhifang Liang ◽  
Fengchun Tian ◽  
Ci Zhang ◽  
Liu Yang
Keyword(s):  
Wound Infection ◽  
Electronic Nose ◽  
Recognition Accuracy ◽  
Interference Suppression ◽  
Laboratory Data ◽  
Clinical Samples ◽  
Culture Solution ◽  
Practical Applications ◽  
Whole Space ◽  
Subspace Alignment

A medical electronic nose (e-nose) with 31 gas sensors is used for wound infection detection by analyzing the bacterial metabolites. In practical applications, the prediction accuracy drops dramatically when the prediction model established by laboratory data is directly used in human clinical samples. This is a key issue for medical e-nose which should be more worthy of attention. The host (carrier) of bacteria can be the culture solution, the animal wound, or the human wound. As well, the bacterial culture solution or animals (such as: mice, rabbits, etc.) obtained easily are usually used as experimental subjects to collect sufficient sensor array data to establish the robust predictive model, but it brings another serious interference problem at the same time. Different carriers have different background interferences, therefore the distribution of data collected under different carriers is different, which will make a certain impact on the recognition accuracy in the detection of human wound infection. This type of interference problem is called “transfer caused by different sample carriers”. In this paper, a novel subspace alignment-based interference suppression (SAIS) method with domain correction capability is proposed to solve this interference problem. The subspace is the part of space whose dimension is smaller than the whole space, and it has some specific properties. In this method, first the subspaces of different data domains are gotten, and then one subspace is aligned to another subspace, thereby the problem of different distributions between two domains is solved. From experimental results, it can be found that the recognition accuracy of the infected rat samples increases from 29.18% (there is no interference suppression) to 82.55% (interference suppress by SAIS).

COVID-19 amongst cancer patients: an experience from Oman

2021 ◽  
Vol 71 (11) ◽  
pp. 2563-2569
Author(s):  
Bassim Jaffar Al Bahrani ◽  
Itrat Mehdi ◽  
Faryal Ali Khamis ◽  
Abdulaziz Mohammed Al Farsi ◽  
Fatma Al Fahdi ◽  
...  
Keyword(s):  
Cancer Patients ◽  
Normal Population ◽  
Human Life ◽  
Laboratory Data ◽  
Normal Subjects ◽  
Limited Information ◽  
Early Evaluation ◽  
Number Of Patients ◽  
Complicated Course ◽  
D Dimer

Introduction: The pandemic of coronavirus has no parallel in recent history. Human Life has completely transformed. There are no approved standard therapies. Patients with comorbidities, old age, immunocompromised, and cancer are at higher risk of complicated course and higher mortality. Patients and Methods: This study is an analysis of Cancer patients who got COVID-19 infection to assess the rate, demographics, laboratory data, and mortality. The data was compared, with normal non-cancer COVID-19 infected patients.  Results: The overall number of COVID-19 positive cancer patients was low (0.47%) compared to normal population (2.17%). The mortality in COVID-19 Positive cancer patients was 35.1% vs 1.03%. Diabetic, hypertensive and cardiac patients are more likely to get COVID-19.  Among Normal subjects, ratio of expatriate patients was higher.  Septicemia was more frequent in cancer patients. Non-cancerous patients were more commonly ventilated.  Leucocytosis, renal impairment, Hypocalcemia, high Troponin, high D-dimer, and high transaminases were seen more in non-cancerous patients. A high Lactate dehydrogenase was more common in cancer patients. The mortality from COVID-19 was higher in cancer patients 25% vs 15.7%. Around 72.8% cancer patients received active treatment with in past 4 weeks before COVID-19 infection. Discussion and Conclusions: There are very few reports of COVID-19 infection in cancer patients. The number of patients is small with limited information and capacity of the healthcare system. Oncologists should consider to tailor cancer clinical management. The cancer patients must practice social distancing, and seek early evaluation for symptoms suspicious for COVID-19, testing for virus and chest radiography. Contintuous...

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