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Optimal microgrid planning for enhancing ancillary service provision

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Journal of modern Power Systems and Clean Energy 2019年第4期7卷 862-875页

作者： Sergio F.CONTRERAS Camilo A.CORTES johanna m.A.mYRZIK Institute of Automation Technology University of BremenOtto-Hahn-Allee 1 NW1/M1050(70)28359 BremenGermany Department of Electrical and Electronics Engineering Universidad Nacional de ColombiaCarrera 30 Calle 45.Ciudad Universitaria Edificio 453Bogota′Colombia

microgrids have presented themselves as an effective concept to guarantee a reliable,efficient and sustainable electricity delivery during the current transition era from passive to active distribution ***,microgrids could offer effective ancillary services(AS)to the power utility,although this will not be possible before the traditional planning and operation methodologies are ***,a probabilistic multi-objective microgrid planning(POmmP)methodology is proposed in this paper to contemplate the large number of variables,multiple objectives,and different constraints and uncertainties involved in the microgrid *** planning methodology is based on the optimal size and location of energy distributed resources with the goal of minimizing the mismatch power in islanded mode,while the residual power for AS provision and the investment and operation costs of the microgrid in grid-connected mode are maximized and minimized,*** that purpose,probabilistic models and a true multi-objective optimization problem are implemented in the *** methodology is tested in an adapted PG&E 69-bus distribution system and the non-dominated sorting genetic algorithmⅡ(NSGA-Ⅱ)optimization method and an analytic hierarchy process for decision-making are used to solve the optimization problem.

关键词： microgrid Ancillary services(AS) Planning multi-objective optimization Decision-making

A LOW-COST OPTImIZATION APPROACH FOR SOLVING mINImUm NORm LINEAR SYSTEmS AND LINEAR LEAST-SQUARES PROBLEmS

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Journal of Computational mathematics 2024年第4期42卷 932-954页

作者： Debora Cores johanna Figueroa Defense University Center at the Spanish Naval Academy Plaza de Espana36920 MarinPontevedraSpain Departamento de matematica Facultad de MatematicaPontificia Universidad Catolica de ChileAv.Vicuna Mackenna 4860San JoaquinSantiago 894000Chile

Recently,the authors proposed a low-cost approach,named Optimization Approach for Linear Systems(OPALS)for solving any kind of a consistent linear system regarding the structure,characteristics,and dimension of the coefficient matrix *** results obtained by this approach for matrices with no structure and with indefinite symmetric part were encouraging when compare with other recent and well-known *** this work,we proposed to extend the OPALS approach for solving the Linear Least-Squares Problem(LLSP)and the minimum Norm Linear System Problem(mNLSP)using any iterative low-cost gradient-type method,avoiding the construction of the matrices AT A or AAT,and taking full advantage of the structure and form of the gradient of the proposed nonlinear objective function in the gradient *** combination of those conditions together with the choice of the initial iterate allow us to produce a novel and efficient low-cost numerical scheme for solving both ***,the scheme presented in this work can also be used and extended for the weighted minimum norm linear systems and minimum norm linear least-squares *** include encouraging numerical results to illustrate the practical behavior of the proposed schemes.

关键词： Nonlinear convex optimization Gradient-type methods Spectral gradient method minimum norm solution linear systems Linear least-squares solution

Estimation of drag forces caused by natural woody vegetation of different scales

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Journal of Hydrodynamics 2014年第4期26卷 608-623页

作者： JALONEN johanna JRVEL Juha Department of Civil and Environmental Engineering Aalto University

To reliably estimate water levels and velocities in vegetated rivers and floodplains, flow resistance models based on physical plant properties are advantageous. The purpose of this study is （1） to assess the suitable parameterization of woody riparian vegetation in estimating the drag forces, （2） to address the effect of plant scale on the drag estimates and reconfiguration, and （3） to evaluate the applicability of three recently developed flow resistance models. Experiments on four tree species in a towing tank together with detailed characterization of tree properties were carried out to establish a novel dataset. Despite the variability in the tree height （0.9 m-3.4 m）, the stem, leaf and total areas proved to be suitable characteristic dimensions for estimating the flow resistance at different scales. Evaluations with independent data revealed that the tested models produced reasonable results. The performance of the models was controlled by the parameter values used rather than the model structure or the plant scale.

关键词： drag force flow resistance woody vegetation modelling

Finding stable multi-component materials by combining cluster expansion and crystal structure predictions

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npj Computational materials 2023年第1期9卷 2137-2146页

作者： Adam Carlsson johanna Rosen martin Dahlqvist materials Design Department of PhysicsChemistryand Biology(IFM)Linköping UniversitySE-58183 LinköpingSweden

A desired prerequisite when performing a quantum mechanical calculation is to have an initial idea of the atomic positions within an approximate crystal *** atomic positions combined should result in a system located in,or close to,an energy ***,designing low-energy structures may be a challenging task when prior knowledge is scarce,specifically for large multi-component systems where the degrees of freedom are close to *** this paper,we propose a method for identification of low-energy crystal structures within multi-component systems by combining cluster expansion and crystal structure predictions with density-functional theory *** structure prediction searches are applied to the mo_(2)AlB_(2) and Sc2AlB_(2) ternary systems to identify candidate structures,which are subsequently used to explore the quaternary(pseudo-binary)(mo_(x)Sc_(1–x))2AlB_(2) system through the cluster expansion formalism utilizing the ground-state search ***,we show that utilizing low-energy structures found within the cluster expansion ground-state search as seed structures within crystal structure predictions of(mo_(x)Sc_(1–x))2AlB_(2) can significantly reduce the computational *** this combined approach,we not only correctly identified the recently discovered mo_(4/3)Sc_(2/3)AlB_(2) i-mAB phase,comprised of in-plane chemical ordering of mo and Sc and with Al in a Kagomélattice,but also predict additional low-energy structures at various *** result demonstrates that combining crystal structure prediction with cluster expansion provides a path for identifying low-energy crystal structures in multi-component systems by employing the strengths from both frameworks.

关键词： structure cluster crystal

Epithelial cell proliferation and glandular atrophy in lymphocytic gastritis: Effect of H pylori treatment

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World Journal of Gastroenterology 2003年第12期9卷 2706-2710页

作者： johanna m.mkinen Seppo Niemel Tuomo Kerola Juhani Lehtola Tuomo J.Karttunen Department of Pathology University of OuluOuluFinland Department of Internal medicine Oulu University HospitalOuluFinland Department of Pathology Lnsi-Pohja Central HospitalKemiFinland

AIm:Lymphocytic gastritis is commonly associated with Helicobacter pylori *** presence of glandular atrophy and foveolar hyperplasia in lymphocytic gastritis suggests abnormalities in cell proliferation and differentiation, forming a potential link with the suspected association with gastric *** aim was to compare epibhelial cell proliferation and morphology in H pylori associated lymphocytic gastritis and H pylori gastritis without features of lymphocytic gastritis, and to evaluate the effect of H pylori treatment. mETHODS:We studied 14 lymphocytic gastritis patients with H pylori *** controls,we selected 14 matched dyspeptic patients participating in another treatment trial whose H pylori infection had successfully been eradicated. Both groups were treated with a triple therapy and followed up with biopsies for 6-18 months (patients) or 3 months (controls).Blinded evaluation for histopathological features was carried *** determine the cell proliferation index, the sections were labeled with Ki-67 antibody. RESULTS:Before treatment,lymphocytic gastritis was characterized by foveolar hyperplasia (P=0.001) and glandular atrophy in the body (P=0.008),and increased proliferation in both the body (P=0.001) and antrum (P=0.002).Proliferation correlated with foveolar hyperplasia and inflammation *** eradication therapy,the number of intraepithelial lymphocytes decreased in the body (P=0.004) and antrum (P=0.065),remaining higher than in controls (Pmultaneously,the proliferation index decreased in the body from 0.38 to 0.15 (P=0.043),and in the antrum from 0.34 to 0.20 (P=0.069),the antral index still being higher in lymphocytic gastritis than in controls (P=0.010). Foveolar hyperplasia and glandular atrophy in the body improved (P=0.021),reaching the non-LG ***: In lymphocytic gastritis, excessive epithelialcell proliferation is predominantly present in the body, where it associates with foveolar hyperpla

关键词： Helicobacter pylori Atrophy Biopsy Cell Division Comparative Study Gastric Fundus Gastric mucosa Gastritis Gastritis, Atrophic Helicobacter Infections Humans Pyloric Antrum

Comparative effectiveness of i-SCAN^(Tm) and high-definition white light characterizing small colonic polyps

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World Journal of Gastroenterology 2012年第41期18卷 5905-5911页

作者： johanna L Chan Li Lin michael Feiler Andrew I Wolf Diana m Cardona Ziad F Gellad Department of medicine Duke University Medical CenterDurham NC 27705 United States Duke Clinical Research Institute DurhamNC 27705 United States Department of Pathology Duke UniversityMedical Center Durham NC 27705 United States Durham VA medical Center Durham NC 27705United States

AIm： To evaluate accuracy of in vivo diagnosis of ad- enomatous vs non-adenomatous polyps using/-SCAN digital chromoendoscopy compared with high-definition white light. mETHODS： This is a single-center comparative effec- tiveness pilot study. Polyps （n = 103） from 75 average- risk adult outpatients undergoing screening or surveil- lance colonoscopy between December 1, 2010 and April 1, 2011 were evaluated by two participating en- doscopists in an academic outpatient endoscopy center. Polyps were evaluated both with high-definition white light and with/-SCAN to make an/n vivo prediction of adenomatous vs non-adenomatous pathology. We de- termined diagnostic characteristics of/-SCAN and high- definition white light, including sensitivity, specificity, and accuracy, with regards to identifying adenomatous vs non-adenomatous polyps. Histopathologic diagnosis was the gold standard comparison. RESULTS： One hundred and three small polyps, de- tected from forty-three patients, were included in the analysis. The average size of the polyps evaluated in the analysis was 3.7 mm （SD 1.3 mm, range 2 mm to 8 mm）. Formal histopathology revealed that 54/103 （52.4%） were adenomas, 26/103 （25.2%） were hyper- plastic, and 23/103 （22.3%） were other diagnoses in- clude ＂lymphoid aggregates＂, ＂non-specific colitis,＂ and ＂no pathologic diagnosis.＂ Overall, the combined accu- racy of endoscopists for predicting adenomas was iden- tical between/-SCAN （71.8%, 95%CI： 62.1%-80.3%） and high-definition white light （71.8%, 95%CI： 62.1%-80.3%）. However, the accuracy of each endosco- pist differed substantially, where endoscopist A demon- strated 63.0% overall accuracy （95%CI： 50.9%-74.0%） as compared with endoscopist B demonstrating 93.3% overall accuracy （95%CI： 77.9%-99.2%）, irrespective of imaging modality. Neither endoscopist demonstrated a significant learning effect with i-SCAN during the study. Though endoscopist A increased accuracy using/-SCAN from 59% （95%CI： 42.1%-74.4%） in the first hal

关键词： Colonoscopy Adenoma Virtual chromoendoscopy Colonic polyps Comparative effectiveness

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Lock Foot Syndrome

上海针灸杂志 2000年第S1期19卷 85-87页

作者： johanna Brand m.D.ofJBQl-Gong International A/S Owner of Qigong A/S Research

Separation of spermatozoa fromerythrocytes using their tumblingmechanism in a pinch flow fractionationdevice

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microsystems & Nanoengineering 2019年第1期5卷 474-480页

作者： johanna T.W.Berendsen Jan C.T.Eijkel Alex m.Wetzels Loes I.Segerink BIOS Lab on a Chip Group MESA+Institute for NanotechnologyTechnical Medical CentreUniversity of TwenteEnschedeThe Netherlands Department of Obstetrics and Gynaecology Radboud University Nijmegen Medical CentreNijmegenThe Netherlands

men suffering from azoospermia can father a child,by extracting spermatozoa from a testicular biopsy *** main complication in this procedure is the presence of an abundance of ***,the isolation of the few spermatozoa from the sample is manually performed due to ineffectiveness of filtering methods,making it time consuming and labor *** spermatozoa are smaller in both width and height than any other cell type found in the sample,with a very small difference compared with the erythrocyte for the smallest,making this not the feature to base the extraction ***,the length of the spermatozoon is 5×larger than the diameter of an erythrocyte and can be *** we propose a microfluidic chip,in which the tumbling behavior of spermatozoa in pinched flow fractionation is utilized to separate them from the *** show that we can extract 95%of the spermatozoa from a sample containing 2.5%spermatozoa,while removing around 90%of the *** adjusting the flow rates,we are able to increase the collection efficiency while slightly sacrificing the purity,tuning the solution for the available sample in the clinic.

关键词： erythrocytes flow utilized

Colorless-to-colorful switching of electrochromic mXene by reversible ion insertion

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Nano Research 2022年第4期15卷 3587-3593页

作者： Jianxia Jiang Leiqiang Qin Joseph Halim Per O.Å.Persson Lintao Hou johanna Rosen Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy materials Physics DepartmentJinan UniversityGuangzhou 510632China Department of Physics Chemistry and Biology(IFM)Linköping UniversityLinköping SE-58183Sweden

Electrochromic(EC)materials that change color with voltage have been widely studied for use in dynamic ***,colorless-to-colorful switching with high contrast ratio is generically unattainable,especially for colorless-to-black electrochromic materials with an ultrahigh contrast ratio over the entire visible *** this work,we developed Nb_(1.33)C mXene-based dynamic windows with colorless-to-black switching of up to 75%reversible change in transmittance from 300 to 1,500 *** exploring the electrochromic effects of different electrolytes through in situ optical changes and electrochemical quartz crystal microbalance(EQCm),it is found that electrochromic behavior is greatly influenced by the extent of reversible Li^(+)insertion/deinsertion between the two-dimensional Nb_(1.33)C mXene *** addition,a colorless-to-black EC device based on Nb_(1.33)C with an overall integrated contrast ratio over 80%was successfully constructed by a solution-processable spin coating *** work enables a simple route to fabricate mXene-based high-performance electrochromic smart windows,which is important for further expanding the application of mXenes to optoelectronic and photonic applications.

关键词： mXenes electrochromic materials colorless-to-black switching high contrast ratio reversible Li^(+)insertion