Study on the Local Scouring of the Bridge with Sediment Control Dam

2012 ◽  
Vol 204-208 ◽  
pp. 2230-2235 ◽  
Author(s):  
Dong Po Sun ◽  
Li Sha Wang ◽  
Peng Tao Wang
Keyword(s):  
Model Experiment ◽  
Multivariate Regression ◽  
Flood Control ◽  
Influence Factors ◽  
Control Design ◽  
Multivariate Regression Analysis ◽  
Shallow Foundation ◽  
The Other ◽  
Sediment Control ◽  
Approach Velocity

Based on the characteristics of local piers scouring after built the sediment control dam in the downstream of the bridge, by the monomer model experiment of flume, sixty groups of local piers scouring experiments have been carried on.The principle and the influence factors of the local piers scouring have been analyzed. The results of series model experiments show that, with the sediment control dams, the local scouring of the piers, on one hand, is influenced by the approach velocity, down-shearing vortex, dimension of the piers, diameter and gradation of the bed sand; on the other hand, it is affected by the elevation of the dam and distance between the pier and the dam. Therefore, the concept of “control slope” is introduced in order to reflect the impacts of the sediment control dam to the piers. Based on the theoretical deduction and dimensional analysis, the equation, which is used to calculate the local scouring with no-uniform bed sand, is acquired by multivariate regression analysis, has been testified by the flume experiment and has got a good result. The optimum value of control slope and the equation of local piers scouring with that dam provide valuable references for bridge flood-control design of the shallow foundation with downstream sediment control dam.

Arterial stiffness could reflect increased cardiac load and reduced pulmonary function in the general population

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
S Murai ◽  
T Sugiura ◽  
Y Dohi ◽  
H Takase ◽  
T Mizoguchi ◽  
...  
Keyword(s):  
Regression Analysis ◽  
General Population ◽  
Arterial Stiffness ◽  
Pulmonary Function ◽  
Multivariate Regression ◽  
Troponin I ◽  
Augmentation Index ◽  
Smoking Status ◽  
Multivariate Regression Analysis ◽  
The Other

Abstract Background Pulmonary function is known to decrease with age and reduced pulmonary function has been reported to be associated with all-cause mortality and cardiovascular death. The association between pulmonary impairment and atherosclerosis was reported previously but has not been investigated sufficiently in the general population. Purpose We hypothesized that arterial stiffness could reflect increase of cardiac load and reduced pulmonary function. The present study aimed to investigate whether increased cardiac load and reduced pulmonary function could affect arterial stiffness in the general population. Methods Subjects undergoing their health check-up were enrolled. Plasma B-type natriuretic peptide (BNP) levels and serum high-sensitivity cardiac troponin I (hs-cTnI) levels were measured to evaluate cardiac load and myocardial damage. Radial augmentation index (rAI) was measured to investigate arterial stiffness using HEM-9000AI device. Subjects with an ST-T segment abnormality on the electrocardiogram, renal insufficiency, cancer, active inflammatory disease, or a history of cardiovascular events and pulmonary disease were excluded. Pulmonary function was assessed using spirometry by calculating forced vital capacity (FVC) as a percentage of predicted value (FVC%-predicted), forced expiratory volume in 1 second (FEV1) as a percentage of predicted value (FEV1%-predicted), and the ratio of FEV1 to FVC (FEV1/FVC). Results A total of 1100 subjects aged 57 years were enrolled and their median values of BNP and hs-cTnI were 15.5 and 2.3 pg/ml. The levels of rAI were significantly associated with the levels of BNP after adjustment for possible confounders in multivariate regression analysis, but were not with the levels of hs-TnI. While the parameters of pulmonary function were inversely associated with the levels of rAI and hs-cTnI after adjustment for possible confounders in the multivariate regression analysis, but not with the levels of BNP. The other multivariate regression analyses where BNP, hs-cTnI, parameters of pulmonary function, and the other possible factors were simultaneously included as independent variables revealed that the BNP levels and the FVC%-predicted or FEV1%-predicted, besides age, gender, smoking status, body mass index, blood pressure, heart rate, creatinine, fasting plasma glucose, and triglyceride, were significantly associated with the levels of rAI. Conclusions The significant associations of rAI with BNP and pulmonary function were revealed in the general population. These findings support that arterial stiffness could reflect increased cardiac load and reduced pulmonary function, in apparently healthy individuals. Funding Acknowledgement Type of funding source: None

scholarly journals Globalisation, Trade Openness and Foreign Direct Investment in Romania

2016 ◽  
Vol 26 (4) ◽  
pp. 41-53 ◽  
Author(s):  
Stela Dima
Keyword(s):  
Foreign Direct Investment ◽  
Regression Analysis ◽  
World Bank ◽  
Direct Investment ◽  
Multivariate Regression ◽  
Trade Openness ◽  
Multivariate Regression Analysis ◽  
The Other ◽  
Foreign Direct Investments ◽  
Market Capitalisation

Abstract The paper analyses the trend of globalisation, trade openness and foreign direct investments (FDI) in Romania and the link between them in the last 25 years. Data from UNCTAD, World Bank and KOF globalisation index were used in econometrical models testing the link between globalisation, trade openness and foreign direct investment. A strong positive and statistical validated link is found between globalisation and FDI, between trade openness and FDI, and between FDI and globalisation. In the context of Romanian economy, these three phenomena are interrelated and each of them is acting to potentiate the effect of the other. Moreover, a multivariate regression analysis emphasized the dependency between globalisation index and foreign direct investment, trade openness and market capitalisation. These results can be taken into account when national policies aiming to attract FDI and stimulating export-import activities are designed.

scholarly journals 1574. Multivariate Regression Analysis to Determine Independent Predictors of Treatment Outcomes in the RESTORE-IMI 2 Trial

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S785-S786
Author(s):  
Robert Tipping ◽  
Jiejun Du ◽  
Maria C Losada ◽  
Michelle L Brown ◽  
Katherine Young ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Clinical Response ◽  
Treatment Outcomes ◽  
Multivariate Regression ◽  
Multivariate Regression Analysis ◽  
Apache Ii Score ◽  
Double Blind ◽  
Mitt Population ◽  
Study Results ◽  
All Cause Mortality

Abstract Background In the RESTORE-IMI 2 trial, imipenem/cilastatin/relebactam (IMI/REL) was non-inferior to PIP/TAZ for treating hospital-acquired/ventilator-associated bacterial pneumonia (HABP/VABP) in the primary endpoint of Day 28 all-cause mortality (D28 ACM) and the key secondary endpoint of clinical response (CR) at early follow-up (EFU; 7-14 d after end of therapy). We performed a multivariate regression analysis to determine independent predictors of treatment outcomes in this trial. Methods Randomized, controlled, double-blind, phase 3, non-inferiority trial comparing IMI/REL 500 mg/250 mg vs PIP/TAZ 4 g/500 mg, every 6 h for 7-14 d, in adult patients (pts) with HABP/VABP. Stepwise-selection logistic regression modeling was used to determine independent predictors of D28 ACM and favorable CR at EFU, in the MITT population (randomized pts with ≥1 dose of study drug, except pts with only gram-positive cocci at baseline). Baseline variables (n=19) were pre-selected as candidates for inclusion (Table 1), based on clinical relevance. Variables were added to the model if significant (p < 0.05) and removed if their significance was reduced (p > 0.1) by addition of other variables. Results Baseline variables that met criteria for significant independent predictors of D28 ACM and CR at EFU in the final selected regression model are in Fig 1 and Fig 2, respectively. As expected, APACHE II score, renal impairment, elderly age, and mechanical ventilation were significant predictors for both outcomes. Bacteremia and P. aeruginosa as a causative pathogen were predictors of unfavorable CR, but not of D28 ACM. Geographic region and the hospital service unit a patient was admitted to were found to be significant predictors, likely explained by their collinearity with other variables. Treatment allocation (IMI/REL vs PIP/TAZ) was not a significant predictor for ACM or CR; this was not unexpected, since the trial showed non-inferiority of the two HABP/VABP therapies. No interactions between the significant predictors and treatment arm were observed. Conclusion This analysis validated known predictors for mortality and clinical outcomes in pts with HABP/VABP and supports the main study results by showing no interactions between predictors and treatment arm. Table 1. Candidate baseline variables pre-selected for inclusion Figure 1. Independent predictors of greater Day 28 all-cause mortality (MITT population; N=531) Figure 2. Independent predictors of favorable clinical response at EFU (MITT population; N=531) Disclosures Robert Tipping, MS, Merck & Co., Inc. (Employee, Shareholder) Jiejun Du, PhD, Merck & Co., Inc. (Employee, Shareholder) Maria C. Losada, BA, Merck & Co., Inc. (Employee, Shareholder) Michelle L. Brown, BS, Merck & Co., Inc. (Employee, Shareholder) Katherine Young, MS, Merck & Co., Inc. (Employee, Shareholder)Merck & Co., Inc. (Employee, Shareholder) Joan R. Butterton, MD, Merck & Co., Inc. (Employee, Shareholder) Amanda Paschke, MD MSCE, Merck & Co., Inc. (Employee, Shareholder) Luke F. Chen, MBBS MPH MBA FRACP FSHEA FIDSA, Merck & Co., Inc. (Employee, Shareholder)Merck & Co., Inc. (Employee, Shareholder)

Epicardial fat thickness as arterial hypertension predictor in normotensive patients with abdominal obesity

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
T Kuznetsova ◽  
M Druzhilov
Keyword(s):  
Blood Pressure ◽  
Regression Analysis ◽  
Blood Glucose ◽  
Waist Circumference ◽  
Arterial Hypertension ◽  
Multivariate Regression ◽  
Fasting Blood Glucose ◽  
Multivariate Regression Analysis ◽  
Epicardial Fat Thickness ◽  
Fat Thickness

Abstract Objective Arterial hypertension (HTN) is one of the most common diseases associated with obesity. Visceral obesity (VO) with dysfunctional visceral adipose tissue plays the main role in obesity induced HTN. Direct criteria of VO including echocardiographic epicardial fat thickness (EFT) may become an additional predictor of HTN. Purpose The aim was to assess the role of echocardiographic EFT (EEFT) as a predictor of HTN in normotensive patients with abdominal obesity (AO). Methods 526 normotensive men (according to ambulatory blood pressure monitoring (ABPM) without therapy) with AO (waist circumference (WC) >94 cm) and SCORE <5%, without cardiovascular diseases and diabetes mellitus were examined (age 45.1±5.0 years). The lipid and glucose profiles, creatinine, uric acid and C-reactive protein blood levels, albuminuria evaluation, echocardiography, carotid ultrasound, bifunctional ABPM were performed. The values of EEFT ≥75 percentile for persons 35–45 years and 46–55 years were 4.8 mm and 5.8 mm respectively. These values used as epicardial VO criteria. Patients with subclinical carotid atherosclerosis due to the lipid-lowering therapy administration (n=98) were excluded from the follow-up. Re-examination with ABPM was conducted on average through 46.3±5.1 months. Data were summarized as mean ± standard error, statistical analysis conducted with paired two-tailed t-tests, Pearson χ2 criterion and multivariate regression analysis. Results Data of 406 persons were available for analysis. HTN as average daily blood pressure ≥130/80 mm Hg was detected in 157 (38.7%) patients. These patients were characterized by initially higher values of age (45.9±4.6 years vs 44.3±4.9 years, p<0.001), waist circumference (106.9±7.3 cm vs 104.2±7.3 cm, p<0.001), body mass index (BMI) (32.0±3.3 kg/m2 vs 30.9±3.2 kg/m2, p<0.001), average daily systolic and diastolic blood pressure (120.7/74.5±4.6/3.4 mm Hg vs 118.2/73.2±5.5/3.9 mm Hg, p<0.001), EEFT (5.2±0.7 mm vs 4.4±1.0 mm, p<0.001). The epicardial VO was initially detected in 95 (23.3%) patients. In patients with HTN the initial prevalence of epicardial VO was greater (58.0% vs 23.3%, p<0.001). As predictors for the multivariate regression analysis the clinical and laboratory examinations data and EEFT were evaluated. According to the results a mathematical model for estimating the probability HTN was obtained: 0.696*fasting blood glucose + 0.198*systolic BP + 2.844*EFT – 40.166 (constant). Among these predictors EEFT was characterized by the highest standardized regression coefficient (0.302, p<0.001) (0.295, p<0.01 for fasting blood glucose, 0.035, p<0.001 for systolic BP). The Hosmer-Lemeshow test value was 0.863, the total percentage of correct classifications was 86%, the area under the ROC-curve was 0.913. Conclusions EEFT (4.8 mm for persons 35–45 years and 5.8 mm for persons 46–55 years) may be an additional predictor of HTN in normotensive patients with AO. Funding Acknowledgement Type of funding source: None

A Multi-Cylinder HCCI Engine Model for Control

2004 ◽  
Author(s):  
Jason S. Souder ◽  
Parag Mehresh ◽  
J. Karl Hedrick ◽  
Robert W. Dibble
Keyword(s):  
Design Process ◽  
Control Design ◽  
The Other ◽  
Variable Valve Timing ◽  
Valve Timing ◽  
Coupling Effects ◽  
Hcci Engine ◽  
Engine Model ◽  
Hcci Engines ◽  
Variable Valve

Homogeneous charge compression ignition (HCCI) engines are a promising engine technology due to their low emissions and high efficiencies. Controlling the combustion timing is one of the significant challenges to practical HCCI engine implementations. In a spark-ignited engine, the combustion timing is controlled by the spark timing. In a Diesel engine, the timing of the direct fuel injection controls the combustion timing. HCCI engines lack such direct in-cylinder mechanisms. Many actuation methods for affecting the combustion timing have been proposed. These include intake air heating, variable valve timing, variable compression ratios, and exhaust throttling. On a multi-cylinder engine, the combustion timing may have to be adjusted on each cylinder independently. However, the cylinders are coupled through the intake and exhaust manifolds. For some of the proposed actuation methods, affecting the combustion timing on one cylinder influences the combustion timing of the other cylinders. In order to implement one of these actuation methods on a multi-cylinder engine, the engine controller must account for the cylinder-to-cylinder coupling effects. A multi-cylinder HCCI engine model for use in the control design process is presented. The model is comprehensive enough to capture the cylinder-to-cylinder coupling effects, yet simple enough for the rapid simulations required by the control design process. Although the model could be used for controller synthesis, the model is most useful as a starting point for generating a reduced-order model, or as a plant model for evaluating potential controllers. Specifically, the model includes the dynamics for affecting the combustion timing through exhaust throttling. The model is readily applicable to many of the other actuation methods, such as variable valve timing. Experimental results validating the model are also presented.

Serum adipokines in patients with psoriatic arthritis and psoriasis alone and their correlation with disease activity

2012 ◽  
Vol 72 (12) ◽  
pp. 1956-1961 ◽  
Author(s):  
Lihi Eder ◽  
Jai Jayakar ◽  
Remy Pollock ◽  
Fawnda Pellett ◽  
Arane Thavaneswaran ◽  
...  
Keyword(s):  
Psoriatic Arthritis ◽  
Multivariate Regression ◽  
Statistical Significance ◽  
Joint Inflammation ◽  
Severity Index ◽  
Serum Levels ◽  
Multivariate Regression Analysis ◽  
Model Assessment ◽  
Continuous Variables ◽  
Factor Α

ObjectiveTo compare the prevalence of metabolic syndrome (MetS) and the levels of related biomarkers in patients with psoriatic arthritis (PsA) and psoriasis without arthritis (PsC).MethodsThis study compared patients with PsA and patients with PsC. The presence of MetS was determined. Serum levels of insulin, adiponectin and leptin were measured. The homeostasis model assessment for insulin resistance (HOMA-IR) was calculated. HOMA-IR, adiponectin and leptin were log-transformed. Continuous variables were compared using the t test and the χ2 test was used for discrete variables. Multivariate regression models were used to investigate the association of MetS and adiponectin with PsA compared to PsC after adjusting for potential confounding variables.Results203 PsA and 155 PsC patients were analysed. The prevalence of MetS was higher in PsA patients compared to those with PsC. However, this did not reach statistical significance (36.5% vs 27.1%, p=0.056). The levels of adipokines were significantly higher in PsA compared to PsC: adiponectin (8.8±5.2 vs 7.4±4.5 log (µg/ml), p=0.009) and leptin in women (3.1±0.8 vs 2.8±0.8, log (ng/ml), p=0.04). HOMA-IR was also higher in PsA (0.97±0.63 vs 0.68±0.81, p<0.001). No difference was observed in leptin levels in men. In multivariate regression analysis, PsA (p=0.04) and the psoriasis area and severity index score (p=0.02) were associated with MetS. Adiponectin was significantly associated with PsA (p=0.005), the use of anti-tumour necrosis factor α therapy (p=0.03) and active joint count (p=0.001).ConclusionsMetS and related adipokines correlated with an increased burden of skin and joint inflammation.

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