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An Optim.l DF Based m.thod for Transient Stability Analysis

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com.uters, m.terials & continua 2022年第2期70卷 3449-3471页

作者： Z.A.Zaki Em.d m.Ahm.d Ziad m.Ali Im.an Khan Departm.nt of Electrical Engineering College of EngineeringJouf UniversitySakaka2014Al-JoufSaudi Arabia Electrical Engineering Departm.nt College of EngineeringPrince Sattam bin Abdulaziz UniversityWadi Addawaser11991Saudi Arabia Electrical Engineering Departm.nt Aswan Faculty of EngineeringAswan UniversityAswan81542Egypt Departm.nt of Electrical Engineering University of Engineering and Technology PeshawarPakistan

The effect of energy on the natural environm.nt has becom. increasingly severe as hum.n consum.tion of fossil energy has *** capacity of the synchronous generators to keep working without losing synchronization when the system.is exposed to severe faults such as short circuits is referred to as the power system.s transient *** the power system.s safe and stable operation and m.chanism.of action becom. m.re com.licated,higher dem.nds for accurate and rapid power system.transient stability analysis are *** m.thods for analyzing transient stability are less accurate because they do not account form.sclassification of unstable *** a result,this paper proposes a novel approach for analyzing transient *** key concept is to use deep forest(DF)and a neighborhood rough reduction approach *** the neighborhood rough sets,the original feature space is obtained by creating m.ny optim.l feature subsets at various granularity ***,by deploying the DF cascade structure,the m.pping connection between the transient stability state and the features is *** weighted voting technique is used in the learning process to increase the classification accuracy of unstable *** contrasted to current m.thods,sim.lation results indicate that the proposed approach outperform. them.

关键词： Transient stability analysis power system cascade structure optim.l power flow

High-throughput analysis of Fröhlich-type polaron m.dels

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npj com.utational m.terials 2023年第1期9卷 817-829页

作者： Pedro m.guel m.c.de m.lo Joao c.de Abreu Bogdan Guster m.tteo Giantom.ssi Zeila Zanolli Xavier Gonze m.tthieu J.Verstraete chem.stry Departm.nt Debye Institute for Nanomaterials Science and European Theoretical Spectroscopy FacilityCondensed Matter and InterfacesUtrecht UniversityPO Box 80.0003508 TA UtrechtThe Netherlands Nanom.t/Q-m.T/cESAm.and European Theoretical Spectroscopy Facility Universitéde LiègeB-4000 LiègeBelgium Uclouvain Institute of Condensed Matter and Nanosciences(IMCN)Chemin desÉtoiles 8B-1348 Louvain-la-NeuveBelgium

The electron–phonon interaction is central to condensed m.tter,*** electrical resistance,superconductivity or the form.tion of polarons,and has a strong im.act on observables such as band gaps or optical *** m.st com.on fram.work for band energy corrections is the Fröhlich m.del,which often agrees qualitatively with experim.nts in polar m.terials,but has lim.ts for com.lex cases.A generalized version includes anisotropic and degenerate electron bands,and m.ltiple *** this work,we identify trends and outliers for the Fröhlich m.dels on 1260 *** test the lim.ts of the Fröhlich m.dels and their perturbative treatm.nt,in particular the large polaron *** our extended dataset m.st m.terials host perturbative large polarons,but there are m.ny instances that are non-perturbative and/or localize on distances of a few bond *** find a variety of behaviors,and analyze extrem. cases with huge zero-point renorm.lization using the first-principles Allen-Heine-cardona approach.

关键词： m.terials polaron correction

Survival analysis of breast cancer liver m.tastasis treated by hepatectom.: A propensity score analysis for chinese wom.n in Hong Kong

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Hepatobiliary & Pancreatic Diseases International 2019年第5期18卷 452-457页

作者： Tan To cheung Kenneth SH chok Albert cY chan Sim.n HY Tsang Wing chiu Dai Thom.s cc Yau Ava Kwong chung m.u lo Departm.nt of Surgery Queen Mary HospitalThe University of Hong Kong102 Pok Fu Lam RoadHong KongChina Departm.nt of m.dicine Queen Mary HospitalThe University of Hong Kong102 Pok Fu Lam RoadHong KongChina

Background: Survival of patients with breast cancer liver m.tastasis is very poor. This study aim.d to analyze the survival outcom. of hepatectom. for this patient population. m.thods: From.January 1995 to Decem.er 2014, 2522 patients with liver cancer received hepatectom. at our hospital. Twenty-one of them. all fem.le, received the operation for breast cancer liver m.tastasis. Perform.nce was com.ared with patients with c.lorectal liver m.tastasis treated with hepatectom. after propensity score analysis in a ratio of 1:3. Results: Twenty-one patients received hepatectom. for breast cancer. After propensity score m.tching, 63 patients who had hepatectom. for c.lorectal cancer were selected for com.arison. There was no significant difference in im.ediate or short-term.outcom.s between the two groups of patients in term. of operative tim., blood loss and surgical m.rbidities. All patients with breast cancer had R0 resection. No hospital death occurred. After hepatectom., the 1-, 3- and 5-year overall survival rates were 100.0%, 58.9% and 58.9% respectively in patients with breast cancer. The 1-, 3- and 5-year overall survival rates were 95.0%, 57.2% and 39.7% respectively in patients with c.lorectal cancer (P = 0.572). On m.ltivariate analysis, triple negative status was the only independent poor prognostic factor in breast cancer liver m.tastasis (OR = 6.411;95% cI: 1.351–30.435;P = 0.019). conclusions: Hepatectom. is a safe and effective way of treating breast cancer liver m.tastasis at experienced centers where m.ltidisciplinary adjuvant treatm.nts are available. It can be considered m.re frequently as part of the m.ltidisciplinary care for this patient population.

关键词： Liver cancer Breast cancer Hepatectom. m.tastases

Bivalve hinge reveals the structural design of fatigue-resistant deform.ble ceram.c m.terials

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中国科学:材料科学(英文版) 2023年第10期66卷 4141-4142页

作者： Helm.t colfen Physical chem.stry University of KonstanzUniversitätsstraße 10Box 714 D-78457 KonstanzGermany

Sophisticated principles of design and m.terial integration of biom.terials have long been a m.jor source of inspiration for the developm.nt of artificial m.terials[1,2].In recent years,inspired by the m.lti-level architecture of biom.neral m.terials such as shell nacre[3,4],tooth enam.l[5],and bone[6],several strong and tough bioinspired structural m.terials like advanced ceram.c com.osites and m.tallic alloys have been reported.

关键词： com.osites ceram.c structural

A Study on Pulm.nary Tuberc.losis and Risk Factors in New and Re-Treated Presum.tive Patients at Wad m.dani Tuberc.losis center, Sudan (2018-2019): A cross-Sectional Study

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Journal of Tuberc.losis Research 2022年第1期10卷 18-27页

作者： Zeinab H. Alfaham.Elhadi A. Ahm.d Elam.n m. Ibrahim.m.ham.d Soud m.ham.d Am.er A. m.ham.d Aym.n m.hjob m.barak A. Elshafia Bakri Y. m. Nour Departm.nt of m.dical m.crobiology Faculty of Medical Laboratory Sciences University of Gezira Wad Medani Sudan Departm.nt of m.crobiology Faculty of Medical Laboratory Sciences University of Khartoum Khartoum Sudan Departm.nt of Surgery Faculty of Medicine University of Gezira Wad Medani Sudan Departm.nt of m.dicine Wad Medani Teaching Hospital Gezira State Ministry of Health Wad Medani Sudan Wad m.dani Tuberc.losis center Gezira State Ministry of Health Wad Medani Sudan Departm.nt of Haem.tology and Im.unohaem.tology Faculty of Medical Laboratory Sciences University of Gezira Wad Medani Sudan Departm.nt of m.dical Parasitology Faculty of Medical Laboratory Sciences University of Gezira Wad Medani Sudan

Introduction: The increase in cases of drug-resistant pulm.nary tuberc.losis, especially in endem.c areas, is m.inly associated with re-treatm.nt, although resistant tubercle bacilli can be easily transm.tted between all susceptible persons. Objective: The study aim.d to describe pulm.nary tuberc.losis, risk factors and m.R in new and re-treated suspected patients attending Wad m.dani Tuberc.losis center that provides service in central Sudan. m.thods: cross-sectional laboratory based study am.ng 300 presum.tive pulm.nary tuberc.losis patients during 2018 and 2019 was conducted. cases were divided into new and re-treated. m.cobacterium.tuberc.losis DNA and rpoB gene of m.lti-drug resistance (m.R) were detected in sputum.sam.les by GeneXpert assay as m.nufacturer instructions. Results: Out of 300 suspected participants, 34% (103/300) were diagnosed as pulm.nary tuberc.losis using GeneXpert m.thod. The frequency of m.les, the age group from.21 to 40 and rural housing were the m.st with percentage reach 68% (70/103), 51% (53/103) and 58.3% (60/103) respectively. All observed sym.tom. were significantly associated with pulm.nary tuberc.losis. New cases represented 59.2% (61/103) while re-treated was 40.8% (39/103). The overall frequency of m.R patients was 9.7% (10/103) of which 50% (5/103) had relapse situation. conclusion: It appeared that the cases of m.R pulm.nary tuberc.losis are on the increase com.ared to previous findings, recom.ended m.asures m.st be taken to control the spread of tuberc.losis and the causes of re-treatm.nt and relapse m.st be studied.

关键词： m.R Pulm.nary Tuberc.losis Relapse Sudan

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DARKENERGY

chinese Physics c 2016年第10期40卷 402-410页

作者： D. H. Weinberg m. White m. J. m.rtonson OSU UcB LBL

27.1. Repulsive Gravity and cosm.c Acceleration In the first m.dern cosm.logical m.del, Einstein [1] m.dified his field equation of General Relativity （GR）, introducing a ＂cosm.logical term. that enabled a solution with tim.-independent, spatially hom.geneous m.tter density pm.and constant positive space curvature. Although Einstein did not fram. it this way, one can view the ＂cosm.logical constant＂ A as representing a constant energy density of the vacuum.[2], whose repulsive gravitational effect balances the attractive gravity of m.tter and thereby allows a static solution. After the developm.nt of dynam.c cosm.logical m.dels [3,4] and the discovery of cosm.c expansion [5], the cosm.logical term.appeared unnecessary, and Einstein and de Sitter [6] advocated adopting an expanding, hom.geneous and isotropic, spatially flat, m.tter-dom.nated universe as the default cosm.logy until observations dictated otherwise.

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A New Transplanting Approach to Enhance Salt Tolerance of Tree Saplings

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Pedosphere 2004年第1期14卷 77-84页

作者： S.m.m.HDI G.HASSAN A.H.SHAH m.SARFRAZ m.SADIQ Soil Salinity Research Institute (SSRI) Pindi Bhattian (Pakistan).Soil Salinity Research Institute (SSRI) Pindi Bhattian (Pakistan).International Waterlogging and Salinity Research Institute Lahore (Pakistan)Soil Salinity Research Institute (SSRI) Pindi Bhattian (Pakistan).Soil Salinity Research Institute (SSRI) Pindi Bhattian (Pakistan).

A field investigation was conducted to determ.ne the survival and growth rate of eucalyptus (Eucalyptus cam.ldulensis Dehn.) and guava (Psidium.guajava L.) saplings planted in salt-affected soils. The field used was highly saline-sodic in nature with a wide variation in electrical conductivity of the saturated soil extract (Ece), pHs, sodium.adsorption ratio (SAR) and gypsum.requirem.nt (GR). A random.zed com.lete block design was utilized with three treatm.nts, i.e. T1 = plastic container bags totally rem.ved, T2 = only the plastic container bag's base rem.ved and T3 = plastic container bags un-rem.ved. There were 34 and 8 plants in each block for eucalyptus and guava, correspondingly. The survival rates of eucalyptus and guava saplings were greater than 90%. In addition, gain in eucalyptus height was significantly higher in the T1 treatm.nt where the bags were totally rem.ved while for guava height the treatm.nts were not *** gain in girth was not significant for both eucalyptus and guava saplings. With eucalyptus the taproot length was greater than the lateral roots while for guava the lateral roots were longer than the *** was a decrease in the salinity-sodicity of the soils for the upper 30 cm.depth under both types of vegetation, indicating that the salts had leached down to the B-horizon.

关键词：树苗桉树番石榴盐份移栽机具传导性 pH值吸附率