499 research outputs found

    Multi-project scheduling with 2-stage decomposition

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    A non-preemptive, zero time lag multi-project scheduling problem with multiple modes and limited renewable and nonrenewable resources is considered. A 2-stage decomposition approach is adopted to formulate the problem as a hierarchy of 0-1 mathematical programming models. At stage one, each project is reduced to a macro-activity with macro-modes resulting in a single project network where the objective is the maximization of the net present value and the cash flows are positive. For setting the time horizon three different methods are developed and tested. A genetic algorithm approach is designed for this problem, which is also employed to generate a starting solution for the exact solution procedure. Using the starting times and the resource profiles obtained in stage one each project is scheduled at stage two for minimum makespan. The result of the first stage is subjected to a post-processing procedure to distribute the remaining resource capacities. Three new test problem sets are generated with 81, 84 and 27 problems each and three different configurations of solution procedures are tested

    Multi-project scheduling with two-stage decomposition

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    We consider a non-preemptive, zero time lag multi-project scheduling problem with multiple modes and limited renewable and nonrenewable resources. A 2-stage decomposition approach is adopted to formulate the problem as a hierarchy of 0-1 mathematical programming models. In stage one; each project is reduced to a macro-activity with macro-modes. The macro-activities are combined into a single macro-activity network over which the macro-activity scheduling problem (MP) is defined, where the objective is the maximization of the net present value with positive cash flows and the renewable resource requirements are time-dependent. An exact solution procedure and a genetic algorithm (GA) approach are proposed for solving the MP. A GA is also employed to generate an initial solution for the exact solution procedure. The first stage terminates with a post-processing procedure to distribute the remaining resource capacities. Using the start times and the resource profiles obtained in stage one, each project is scheduled in stage two for minimum makespan. Three new test problem sets are generated with 81, 84 and 27 problems each, and three different configurations of solution procedures are tested

    Autonomous car parking system with various trajectories

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    In this study, an algorithm presents a solution to 4-wheel-car parking. This algorithm is suitable for parallel parking between two objects or two cars. Firstly the system verifies whether enough space. After finding a valid parking space, system makes the suitable movements for a perfect parking. This parking operation is tested in a simulation environment using MatLab-Simulink

    Prevalence and Associated Features of Anxiety Disorder Comorbidity in Bipolar Disorder: A Meta-Analysis and Meta-Regression Study

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    Objective: Bipolar disorder is highly comorbid with anxiety disorders, however current and lifetime comorbidity patterns of each anxiety disorder and their associated features are not well studied. Here, we aimed to conduct a meta-analysis and meta-regression study of current evidence.Method: We searched PubMed to access relevant articles published until September 2015, using the keywords “Bipolar disorder” or “Affective Psychosis” or “manic depressive” separately with “generalized anxiety,” “panic disorder,” “social phobia,” “obsessive compulsive,” and “anxiety.” Variables for associated features and prevalence of anxiety disorders were carefully extracted.Results: Lifetime any anxiety disorder comorbidity in BD was 40.5%; panic disorder (PD) 18.1%, generalized anxiety disorder (GAD) 13.3%, social anxiety disorder (SAD) 13.5% and obsessive compulsive disorder (OCD) 9.7%. Current any anxiety disorder comorbidity in BD is 38.2%; GAD is 15.2%, PD 13.3%, SAD 11.7%, and OCD 9.9%. When studies reporting data about comorbidities in BDI or BDII were analyzed separately, lifetime any anxiety disorder comorbidity in BDI and BDII were 38% and 34%, PD was 15% and 15%, GAD was 14% and 16.6%, SAD was 8% and 13%, OCD was 8% and 10%, respectively. Current any DSM anxiety disorder comorbidity in BDI or BDII were 31% and 37%, PD was 9% and 13%, GAD was 8% and 12%, SAD was 7% and 11%, and OCD was 8% and 7%, respectively. The percentage of manic patients and age of onset of BD tended to have a significant impact on anxiety disorders. Percentage of BD I patients significantly decreased the prevalence of panic disorder and social anxiety disorder. A higher rate of substance use disorder was associated with greater BD–SAD comorbidity. History of psychotic features significantly affected current PD and GAD.Conclusions: Anxiety disorder comorbidity is high in BD with somewhat lower rates in BDI vs BDII. Age of onset, substance use disorders, and percentage of patients in a manic episode or with psychotic features influences anxiety disorder comorbidity

    The Relationship between Previous Lower Extremity Injury, Body Weight and Bilateral Eccentric Hamstring Strength Imbalance in Young Soccer Players

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    Th is study aims to investigate the eff ect of lower extremity (LE) injuries on bilateral hamstring eccentric strength imbalance (HSI) and to determine the relationship between body weight (BW) and HSI in young male soccer players. Eighty-eight young soccer players aged 14-19 in Turkey voluntarily participated in this study. Eccentric hamstring strength measurements were taken using a NordBord® Hamstring Testing Device. To obtain the LE backgrounds of the participants, individual interviews were administered to the players, and the obtained data were verifi ed through a review of previous injury records. While 22 (25%) out of 88 players reported LE injuries in the previous two years (injured players (IP)), the rest of them (75%) did not report any LE injuries (non-injured players (NP)). HSI values as peak forces were computed by extracting the weaker leg values from the stronger leg values. Both the Analysis of Variance (ANOVA) and the Analysis of Covariance (ANCOVA) were performed, controlling the BW eff ect in order to test the eff ects of LE injuries on HSI. Correlation analysis was also conducted, taking into consideration the previous research fi ndings on the relationship between body weight and strength variables. Th ere was signifi cant relationship between BW and HSI ((p r >0.02)) and non-signifi cant results for HSI (F (1.85) =0.578, p>0.05). However, the eff ect of BW was signifi cant for HSI (F (1.85) =3.91, p<0.05, η2 = 0.068). Th is study supported the hypothesis that hamstring muscle strength imbalance is not aff ected by lower extremity injuries and that body weight is a factor that may aff ect strength imbalance

    The local clinical validation of a new lithium heparin tube with a barrier: BD Vacutainer® Barricor LH Plasma tube

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    Introduction: Although serum-providing blood tubes with a barrier are still widely used due to their significant advantages, the use of blood tubes with a barrier to provide plasma is becoming widespread. We compared 22 analytes in a BD Vacutainer® Barricor LH Plasma tube for local clinical validation of this new lithium heparin tube with a barrier. Materials and methods: Samples from 44 volunteers were collected in different tubes (Becton Dickinson and Company): Z tube without additive (reference), clot-activator tube with gel (SST), lithium heparin tube without gel (LiH), and lithium heparin tube with barrier (Barricor). Analyte concentrations in different tubes were compared with the reference tube. All tubes were also evaluated according to additional testing (different centrifugation durations, blood-sampling techniques and individual differences). Results: Aspartate aminotransferase (AST), glucose (Glc), potassium (K), lactate dehydrogenase (LD), sodium (Na), and total protein (TP) had a significant bias in Barricor (9.19%, - 3.24%, - 4.88%, 21.60%, - 0.40%, 5.03%, respectively) relative to the reference tube. There was no statistical difference between different centrifugation durations and individual differences for AST, K and LD in LiH and/or Barricor (P > 0.05). There was a significant bias for LD between LiH and Barricor in terms of blood-sampling techniques (21.2% and 12.4%, respectively). Conclusions: Recently, the use of plasma has become prominent due to some of its advantages. In this study, plasma AST, K, LD, Glc and TP levels in Barricor were clinically different in comparison to serum. The results of additional tests showed that higher levels of LD in Barricor did not result from haemolysis, and they might be related to other factors including number of platelets, cellular fragility, or functional environment

    Safety and technical efficacy of early minimally invasive endoscopy-guided surgery for intracerebral haemorrhage:the Dutch Intracerebral haemorrhage Surgery Trial pilot study

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    Background: Previous randomised controlled trials could not demonstrate that surgical evacuation of intracerebral haemorrhage (ICH) improves functional outcome. Increasing evidence suggests that minimally invasive surgery may be beneficial, in particular when performed early after symptom onset. The aim of this study was to investigate safety and technical efficacy of early minimally invasive endoscopy-guided surgery in patients with spontaneous supratentorial ICH. Methods: The Dutch Intracerebral Haemorrhage Surgery Trial pilot study was a prospective intervention study with blinded outcome assessment in three neurosurgical centres in the Netherlands. We included adult patients with spontaneous supratentorial ICH ≥10mL and National Institute of Health Stroke Scale (NIHSS) score ≥2 for minimally invasive endoscopy-guided surgery within 8 h after symptom onset in addition to medical management. Primary safety outcome was death or increase in NIHSS ≥4 points at 24 h. Secondary safety outcomes were procedure-related serious adverse events (SAEs) within 7 days and death within 30 days. Primary technical efficacy outcome was ICH volume reduction (%) at 24 h. Results: We included 40 patients (median age 61 years; IQR 51–67; 28 men). Median baseline NIHSS was 19.5 (IQR 13.3–22.0) and median ICH volume 47.7mL (IQR 29.4–72.0). Six patients had a primary safety outcome, of whom two already deteriorated before surgery and one died within 24 h. Sixteen other SAEs were reported within 7 days in 11 patients (of whom two patients that already had a primary safety outcome), none device related. In total, four (10%) patients died within 30 days. Median ICH volume reduction at 24 h was 78% (IQR 50–89) and median postoperative ICH volume 10.5mL (IQR 5.1–23.8). Conclusions: Minimally invasive endoscopy-guided surgery within 8 h after symptom onset for supratentorial ICH appears to be safe and can effectively reduce ICH volume. Randomised controlled trials are needed to determine whether this intervention also improves functional outcome. Trial registration: Clinicaltrials.gov : NCT03608423, August 1st, 2018.</p
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