72 research outputs found

    Optimization for Variable Height Wind Farm Layout Model

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    The optimization of wind farm layouts is very important for the effective utilization of wind resources. A fixed wind turbine hub height in the layout of wind farms leads to a low wind energy utilization and a higher LCOE (levelized cost of electricity). WOMH (Wind Farm Layout Optimization Model Considering Multiple Hub Heights) is proposed in this paper to tackle the above problem. This model is different from the traditional fixed hub height model, as it uses a variable height wind turbine. In WOMH, the Jensen wake and Weibull distribution are used to describe the wake effect on the wind turbines and wind speed distribution, respectively. An algorithm called DEGM (differential evolution and greedy method with multiple strategies) is proposed to solve WOMH, which is NP hard. In the DEGM, seven strategies are designed to adjust the distribution coordinates of wind turbines so that the height of the wind turbines will be arranged from low to high in the wind direction. This layout reduces the Jensen wake effect, thus reducing the value of the LCOE. The experimental results show that in the DEGM, when the number of wind turbines is 5, 10, 20, 30 and 50, the WOMH reduces the LCOE by 13.96%, 12.54%, 8.22%, 6.14% and 7.77% compared with the fixed hub height model, respectively. In addition, the quality of the solution of the DEGM is more satisfactory than that of the three-dimensional greedy algorithm and the DEEM (differential evolution with a new encoding mechanism) algorithm. In the case of five different numbers of wind turbines, the LCOE of DEGM is at least 3.67% lower than that of DEEM, and an average of 6.83% lower than that of three-dimensional greedy. The model and algorithm in this paper provide an effective solution for the field of wind farm layout optimization

    Design and Analysis of a High-Speed Claw Pole Motor With Soft Magnetic Composite Core

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    Transitional Zone Index and Intravesical Prostatic Protrusion in Benign Prostatic Hyperplasia Patients: Correlations according to Treatment Received and Other Clinical Data

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    Purpose: The aim of this research was to assess the value of the transitional zone index (TZI) and intravesical prostatic protrusion (IPP) from transrectal ultrasonography in evaluating the severity and progression of disease by analyzing the relationship between the 2 parameters and symptoms, clinical history, and urodynamics in benign prostatic hyperplasia (BPH) patients undergoing different treatment. Materials and Methods: A total of 203 patients receiving medication and 162 patients who underwent transurethral resection of the prostate because of BPH were enrolled in this retrospective analysis. The clinical history and subjective and objective examination results of all patients were recorded and compared after being classified by TZI and IPP level. Linear regression was used to find correlations between IPP, TZI, and urodynamics. Results: The 2 parameters were found to differ significantly between patients receiving medication and patients undergoing surgical therapy (p<0.05). PSA, maximum flow rate (Qmax), detrusor pressure at Qmax (PdetQmax), and the bladder outlet obstruction index (BOOI) differed according to various TZI levels (p<0.05). In addition, the voiding symptom score, Qmax, and BOOI of subgroups with various IPP levels were also significantly different (p<0.05). Both TZI and IPP had significant effects on Qmax, BOOI, and PdetQmax (p<0.05) and the incidence of acute urinary retention (p=0.000). Conclusions: The results demonstrated that both TZI and IPP had favorable value for assessing severity and progression in patients with BPH. Further studies are needed to confirm whether the two parameters have predictive value in the efficacy of BPH treatment and could be considered as factors in the selection of therapy

    In Vivo Molecular MRI Imaging of Prostate Cancer by Targeting PSMA with Polypeptide-Labeled Superparamagnetic Iron Oxide Nanoparticles

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    The prostate specific membrane antigen (PSMA) is broadly overexpressed on prostate cancer (PCa) cell surfaces. In this study, we report the synthesis, characterization, in vitro binding assay, and in vivo magnetic resonance imaging (MRI) evaluation of PSMA targeting superparamagnetic iron oxide nanoparticles (SPIONs). PSMA-targeting polypeptide CQKHHNYLC was conjugated to SPIONs to form PSMA-targeting molecular MRI contrast agents. In vitro studies demonstrated specific uptake of polypeptide-SPIONs by PSMA expressing cells. In vivo MRI studies found that MRI signals in PSMA-expressing tumors could be specifically enhanced with polypeptide-SPION, and further Prussian blue staining showed heterogeneous deposition of SPIONs in the tumor tissues. Taken altogether, we have developed PSMA-targeting polypeptide-SPIONs that could specifically enhance MRI signal in tumor-bearing mice, which might provide a new strategy for the molecular imaging of PCa

    Research on the application of VRP theory in logistics transportation

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    Logistics transportation problem is a hot issue in today’s research, with the diversification of transport vehicles, the complexity of the transportation network, the choice of logistics transportation route is a NP problem in combinatorial optimization. The paper discusses the relevant knowledge of VRP and physical distribution routing, such as the relationship between them, how to describe the distribution problem with VRP, how to build up mathematical model and so on and meanwhile, points out the direction of research

    Étude du potentiel de découverte du boson de Higgs produit par fusion de bosons vectoriels qq a qq H par le détecteur ATLAS au LHC

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    At the LHC, the vector boson fusion production mode will have a major im- pact on the Standard Model Higgs searches. The characteristic signature of two addition al jets in the forward regions of the detector and the low hadronic activity in the central part allows for a powerful rejection of background processes. This process is also the unique way for detecting H -t 7+7- decay mode. The work presented in this thesis shows the prospect for a Higgs boson, with H -t 7+ 7- and 100 < MH < 150 GeV jc 2 , discovery in ATLAS using vector boson fusion. In addi- tion, the production of the dominant background pro cess pp -t Z + 2 jets is studied using several theoretical approaches. Finally, The ATLAS Forward Calorimeter will have a major role in detecting and reconstructing the forward jets associated with the Higgs boson. A comparison with a GEANT4-based Monte Carlo simulation and test beam data of a prototype of the forward calorimeter has allowed a good description of the experimental data and a good understanding of its performances as weIl. Such comparison has also shown that GEANT4 is a very good tool for Monte Carlo simulations of LHC detectors

    Research on the application of VRP theory in logistics transportation

    No full text
    Logistics transportation problem is a hot issue in today’s research, with the diversification of transport vehicles, the complexity of the transportation network, the choice of logistics transportation route is a NP problem in combinatorial optimization. The paper discusses the relevant knowledge of VRP and physical distribution routing, such as the relationship between them, how to describe the distribution problem with VRP, how to build up mathematical model and so on and meanwhile, points out the direction of research
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