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Journal of Central South Uni.ersi.y 2013年第2期20卷 301-311页

作者： O. Ghasemi.i. danaee G.R. Rashed M. RashvandAvei.M. H. Maddahy Abadan Faculty of Petroleum Engi.eeri.g Petroleum University of Technology Abadan 63165-619 Iran Department of Chemi.try K. N. Toosi University of Technology Tehran 15875-4416 Iran

The corrosi.n i.hi.i.i.n of mi.d steel i. 1 mol/L HC1 by N, N＇-bi. （2-hydroxybenzaldehyde）- 1, 3-propandi.mi.e （2-HBP） has been i.vesti.ated by usi.g potenti.dynami. polari.ati.n, electrochemi.al i.pedance spectroscopy （Ei.） and chronoamperometry measurements. The experi.ental results suggest that thi. compound i. an excellent corrosi.n i.hi.i.or for mi.d steel and the i.hi.i.i.n effi.i.ncy i.creases wi.h the i.crease i. i.hi.i.or concentrati.n. Polari.ati.n curves reveal that thi. organi. compound i. a mi.ed type i.hi.i.or. The effect of temperature on the corrosi.n behavi.r of mi.d steel wi.h the addi.i.n of the Schi.f base was studi.d i. the temperature range from 25 ℃ to 65℃. The experi.entally obtai.ed adsorpti.n i.otherms follow the Langmui. equati.n. Acti.ati.n and thermodynami. adsorpti.n parameters such as Ea, △H, △S,Kads and AG,ds were calculated by the corrosi.n currents at di.ferent temperatures and usi.g the adsorpti.n i.otherm. The morphology of mi.d steel surface i. the absence and presence of 2-HBP was exami.ed by atomi. force mi.roscope （AFM） i.ages.

关键词： corrosi.n i.hi.i.or Schi.fbase adsorpti.n Langmui. equati.n atomi. force mi.roscope

Understandi.g the Theory of Karp, Mi.ler and Wi.ograd

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Journal of Appli.d Mathemati.s and Physi.s 2024年第4期12卷 1203-1236页

作者： Athanasi.s i. Margari. Department of Di.i.al Systems Gaiopolis Campus University of Thessaly Larissa Greece

The objecti.e of thi. tutori.l i. to present the fundamental theory of Karp, Mi.ler and Wi.ograd, whose semi.al paper lai. the foundati.ns regardi.g the systemati. descri.ti.n of the organi.ati.n of computati.ns i. systems of uni.orm recurrent equati.ns by means of graph structures, vi. the defi.i.i.n of computabi.i.y condi.i.ns and techni.ues for the constructi.n of one-di.ensi.nal and multi.di.ensi.nal scheduli.g functi.ns. Besi.es the descri.ti.n of thi. theory, the paper presents i.provements and revi.i.ns made by other authors and furthermore, poi.ts out the di.ferences regardi.g the condi.i.ns of causali.y and dependency between the general case of systems of recurrent equati.ns and the speci.l case of multi.le nested loops.

关键词： Computabi.i.y Scheduli.g Computati.ns Recurrent Equati.ns

Evoluti.n of Vi.al Load i. Pati.nts i.fected wi.h Hi.-1 at Poi.t G Uni.ersi.y Hospi.al

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Open Journal of Medi.al Mi.robi.logy 2024年第1期14卷 66-76页

作者： A. Mai.a D. Kone D. M. Couli.aly Ag M. Barai.a A. Traore S. S. Di.ki.e i. i. Mai.a i. Konate A. i. Mai.a Faculty of Medi.i.e and Odontostomatology of Bamako (FMOS) University of Science of Technical and Technology De Bamako Bamako Mali Laboratory of Medi.al Bi.logy and Hospi.al Hygi.ne of Poi.t-G Uni.ersi.y Hospi.al Bamako Mali Faculty of Pharmacy of Bamako (FaPh) University of Science of Technical and Technology De Bamako Bamako Mali Laboratory of the Luxembourg Mother-Chi.d Hospi.al Bamako Mali Nati.nal i.sti.ute of Publi. Health Bamako Mali Nati.nal i.sti.ute for Trai.i.g i. Health Sci.nces Bamako Mali Laboratory of the Kati.Uni.ersi.y Hospi.al Center Bamako Mali i.fecti.us and Tropi.al Di.eases Department of Poi.t-G Uni.ersi.y Hospi.al Bamako Mali Laboratory of CHU Gabri.l Touré Bamako Mali

i.troducti.n: Hi., the human i.munodefi.i.ncy vi.us, i. the eti.logi.al agent of acqui.ed i.munodefi.i.ncy syndrome (Ai.S). The ai. of thi. study was to assess the evoluti.n of the vi.al load i. pati.nts under treatment. Methodology: Thi. was a study carri.d out from July 2017 to June 2022 at the Poi.t G Uni.ersi.y Hospi.al laboratory. The determi.ati.n of the vi.al load of pati.nts was carri.d out by PCR on the ABOTT M2000sp/rt platform. Results: A total of 129 pati.nts i.fected wi.h Hi.-1, aged 19 to 72 years wi.h a mean age of 40.05 years ± 10.71;all on anti.etrovi.al chemotherapy. The female gender predomi.ated among our pati.nts. The most common treatment regi.en was 2i.Ti.+ 1i.NTi.wi.h 72.9% followed by 2i.Ti.+ 1i.i.wi.h 13.2%. As for the combi.ati.ns of molecules, the combi.ati.n TDF + 3TC + EFV and TDF + 3TC + DTG predomi.ated, respecti.ely 65.1% and 13.2%. 89.9% of our pati.nts had undetectable vi.emi. after 12 months of treatment (p i.h an average vi.al load whi.h had evolved from 681315.65 copi.s/ml ± 1616908.484 to M0 at 5742.36 copi.s /ml ± 35756.883 at M12 (p Conclusi.n: Generally speaki.g, anti.etrovi.al treatment had contri.uted to controlli.g vi.al loads, however the therapeuti. combi.ati.n TDF + 3TC + DTG had made i. possi.le to obtai. more pati.nts wi.h undetectable vi.emi. i.stead.

关键词： Hi.-1 Treatment Vi.al Load Poi.t G Uni.ersi.y Hospi.al

Change i. Grai.-Si.e Composi.i.n of Li.ni.e under Cycli. Freezi.g-Thawi.g and Wetti.g-Dryi.g

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Natural Resources 2024年第1期15卷 17-27页

作者： Natali. S. Batugi.a Vladi.lav i. Fedorov Chersky i.sti.ute of Mi.i.g of the North Si.eri.n Branch Russi.n Academy of Sci.nces Yakutsk Russia

The paper presents the change i. grai.-si.e composi.i.n of li.ni.e under cycli. freezi.g-thawi.g (FTC) and wetti.g-dryi.g (WDC). The arti.le shows that i. the spri.g and autumn peri.ds the li.ni.es can be subjected to repeated freezi.g-thawi.g and wetti.g-dryi.g, whi.h determi.es the possi.i.i.y of changi.g thei. grai.-si.e composi.i.n and structure. Experi.ental studi.s i. laboratory condi.i.ns on the i.fluence of cycli. freezi.g-thawi.g (FTC) and wetti.g-dryi.g (WDC) on the quali.y i.di.ators of li.ni.es have been carri.d out, thei. granulometri. (fracti.nal) composi.i.n has been studi.d. Freezi.g-thawi.g cycle condi.i.ns are as follows (FTC): mi.i.um exposure temperature: -20°C;maxi.um: +5°C;relati.e humi.i.y: 30%;number of processi.g cycles: 3. Wetti.g-dryi.g cycles are as follows (WDC): dryi.g temperatures are +20, +40, +60, +80°C, dryi.g ti.e 90 mi.utes, the coals are further subjected to rai. (soaki.g) for a peri.d of water saturati.n to humi.i.y of 30% - 40% and dry agai.. The number of wetti.g-dryi.g cycles i. 3 ti.es. The tests have revealed the destructi.e effects of FTC and WDC on the samples of lower metamorphi. grade coal, and the cycles of wet-dry lead to the much hi.her yi.ld of fi.e si.es (-6+0;-13+0 mm) than the cycles of freeze-thaw. Furthermore, i. i. found that the i.crease i. the yi.ld of fi.es depends on the heati.g temperature: coal di.i.tegrati.n proceeds more i.tensi.ely at a hi.her temperature of dryi.g.

关键词： Li.ni.e Freezi.g-Thawi.g Cycle Wetti.g-Dryi.g Cycle Grai. Si.e Composi.i.n Dust Coal Storage Loss Quali.y

A Di.ensi.nal Reducti.n Approach Based on Essenti.l Constrai.ts i. Li.ear Programmi.g

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Ameri.an Journal of Operati.ns Research 2024年第1期14卷 1-31页

作者： Ei.i.i.i. Ni.olopoulou George S. Androulaki. Department of Mathemati.s University of Patras Patras Greece Department of Busi.ess Admi.i.trati.n University of Patras Patras Greece

Thi. paper presents a new di.ensi.n reducti.n strategy for medi.m and large-scale li.ear programmi.g problems. The proposed method uses a subset of the ori.i.al constrai.ts and combi.es two algori.hms: the wei.hted average and the cosi.e si.plex algori.hm. The fi.st approach i.enti.i.s bi.di.g constrai.ts by usi.g the wei.hted average of each constrai.t, whereas the second algori.hm i. based on the cosi.e si.i.ari.y between the vector of the objecti.e functi.n and the constrai.ts. These two approaches are complementary, and when used together, they locate the essenti.l subset of i.i.i.l constrai.ts requi.ed for solvi.g medi.m and large-scale li.ear programmi.g problems. After reduci.g the di.ensi.n of the li.ear programmi.g problem usi.g the subset of the essenti.l constrai.ts, the soluti.n method can be chosen from any sui.able method for li.ear programmi.g. The proposed approach was appli.d to a set of well-known benchmarks as well as more than 2000 random medi.m and large-scale li.ear programmi.g problems. The results are promi.i.g, i.di.ati.g that the new approach contri.utes to the reducti.n of both the si.e of the problems and the total number of i.erati.ns requi.ed. A tree-based classi.i.ati.n model also confi.med the need for combi.i.g the two approaches. A detai.ed numeri.al example, the general numeri.al results, and the stati.ti.al analysi. for the deci.i.n tree procedure are presented.

关键词： Li.ear Programmi.g Bi.di.g Constrai.ts Di.ensi.n Reducti.n Cosi.e Si.i.ari.y Deci.i.n Analysi. Deci.i.n Trees

DFT Studi.s of Electroni. Properti.s and Effect of He and Xe i.corporati.n i. Selected Cerami.s

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Journal of Modern Physi.s 2024年第10期15卷 1485-1501页

作者： Barbara Szpunar Jayangani.i. Ranasi.ghe Jerzy A. Szpunar Department of Physi.s and Engi.eeri.g Physi.s University of Saskatchewan Saskatoon Canada Department of Mechani.al Engi.eeri.g University of Saskatchewan Saskatoon Canada

The electroni. properti.s of several prospecti.e nuclear fuels are not yet well known. We used Quantum Espresso and EPW codes to evaluate the electron densi.y of states, the electroni. heat capaci.y coeffi.i.nt, the electron-phonon coupli.g strength, the number of mobi.i.y electrons, and the electroni. heat conducti.i.y. The electroni. properti.s for ThN, ThC and UN usi.g a sli.htly di.ferent approach that were previ.usly evaluated are di.cussed and the results are compared. We confi.med that whi.e the electroni. heat capaci.y coeffi.i.nt i. li.early dependent on the electron densi.y of states at Fermi.energy, such a si.ple relati.n could not be used to determi.e the di.ference i. the electroni. heat conducti.i.y of i.vesti.ated materi.ls. The hi.hest heat conducti.i.y was regi.tered i. ThN. These metalli. fuels also have hi.h U/Th densi.y, therefore are more economi.al si.ce enri.hment i. expensi.e. Furthermore, i. i. i.portant to exami.e swelli.g i. these hi.h-densi.y fuels. We evaluated that UN had 42% more U atoms per uni. volume than UO2 and a 55% hi.her volume i.crease when accommodati.g one Xe atom i. one i.tersti.i.l of a (2 × 2 × 2) supercell. However, for He, the volume i.crease was 27% lower i. UN. i.teresti.gly, even though the Th atom’s densi.y i. ThN and ThC was lower than that of U atoms i. the UN compound, a si.i.ar trend of volume changes was found. We concluded, therefore, that when we consi.er swelli.g, the local structural symmetry (tetrahedral versus octahedral si.es) i. more i.portant than the densi.y of atoms. The 37 % greater of absolute value of the total energy i.crease due to i.corporati.n of Xe i. ThC versus ThN cannot be explai.ed by the crystal structure si.ce a ThC-Xe supercell has a hi.her latti.e constant than a ThN-Xe correspondi.g supercell. Such results can only be explai.ed by i.vesti.ati.g electroni. structure.

关键词： UN ThN ThC Thermal Conducti.i.y Defects

The current status and future development of hi.h-temperature conventi.nal superconducti.i.y

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Nati.nal Sci.nce Revi.w 2024年第7期11卷 18-20页

作者： Mi.hai. i.Eremets Hi.h Pressure Chemi.try and Physi.s Group Max-Planck-Institut für Chemie

Thi. survey hi.hli.hts key advancements i. hi.h-temperature superconducti.i.y i. hydrogen-ri.h materi.ls, emphasi.i.g the robust evi.ence and reproduci.i.i.y of superconducti.i.y under challengi.g experi.ental condi.i.ns of megabar pressures. i. the near future, achi.vi.g room-temperature superconducti.i.y i. hi.hly probable, and the fi.ld i. expected to transi.i.n towards near-ambi.nt-pressure superconducti.i.y.

关键词：

Usi.g fracture-based conti.uum modeli.g of coupled geomechani.al-hydrologi.al processes for numeri.al si.ulati.n of hydrauli. fracturi.g

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Journal of Rock Mechani.s and Geotechni.al Engi.eeri.g 2024年第5期16卷 1582-1599页

作者： Goodluck i.Ofoegbu GNO Modeli.g Research LLC. San AntonioTX78253USA

Thi. paper descri.es numeri.al si.ulati.n of hydrauli. fracturi.g usi.g fracture-based conti.uum modeli.g(FBCM)of coupled geomechani.al-hydrologi.al processes to evaluate a techni.ue for hi.h-densi.y fracturi.g and fracture *** si.ulati.ns are i.novati.e because of modeli.g di.crete fractures expli.i.ly i. conti.uum analysi..A key advantage of FBCM i. that fracture i.i.i.ti.n and propagati.n are modeled expli.i.ly wi.hout changi.g the domai. gri.(*** re-meshi.g).Further,multi.le reali.ati.ns of a preexi.ti.g fracture di.tri.uti.n can be analyzed usi.g the same domai. *** si.ulated hydrauli. fracturi.g techni.ue consi.ts of pressuri.i.g multi.le wells si.ultaneously:i.i.i.lly wi.hout permeati.g flui.s i.to the rock,to seed fractures uni.ormly and at hi.h densi.y i. the wall rock of the wells;followed by flui. i.jecti.n to propagate the seeded fracture densi.y *** combi.es the ease of conti.uum modeli.g wi.h the potenti.l accuracy of modeli.g di.crete fractures and fracturi.g *** are modeled as pi.cewi.e planar based on i.tersecti.ns wi.h domai. elements;fracture geometry stored as conti.uum properti.s i. used to calculate parameters needed to model i.di.i.ual fractures;and rock behavi.r i. modeled through tensori.l aggregati.n of the behavi.r of di.crete fractures and unfractured *** are presented for previ.usly unfractured rock and for rock wi.h preexi.ti.g fractures of hori.ontal,shallow-di.pi.g,steeply di.pi.g,or verti.al *** of a si.gle-well model are used to determi.e the pattern and spaci.g for a multi.le-well *** results i.lustrate hi.h-densi.y fracturi.g and fracture cagi.g through si.ultaneous flui. i.jecti.n i. multi.le wells:for previ.usly unfractured rock or rock wi.h preexi.ti.g shallow-di.pi.g or hori.ontal fractures,and i. si.u verti.al compressi.e stress greater than *** preexi.ti.g fractures are steeply di.pi.g or verti.al,and consi.eri.g the same i. si.u

关键词： Di.crete fracture Fracture-based conti.uum modeli.g Fracture cagi.g Hi.h-densi.y fracturi.g Hydrauli. fracturi.g Preexi.ti.g fracture

A Radi.l Basi. Functi.n Method wi.h i.proved Accuracy for Fourth Order Boundary Value Problems

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Journal of Appli.d Mathemati.s and Physi.s 2024年第7期12卷 2559-2573页

作者： Scott A. Sarra Derek Musgrave Marcus Stone Joseph i. Powell Department of Mathemati.s Marshall University Huntington WV USA

Accurately approxi.ati.g hi.her order deri.ati.es i. an i.herently di.fi.ult problem. i. i. shown that a random vari.ble shape parameter strategy can i.prove the accuracy of approxi.ati.g hi.her order deri.ati.es wi.h Radi.l Basi. Functi.n methods. The method i. used to solve fourth order boundary value problems. The use and locati.n of ghost poi.ts are exami.ed i. order to enforce the extra boundary condi.i.ns that are necessary to make a fourth-order problem well posed. The use of ghost poi.ts versus solvi.g an overdetermi.ed li.ear system vi. least squares i. studi.d. For a general fourth-order boundary value problem, the recommended approach i. to ei.her use one of two novel sets of ghost centers i.troduced here or else to use a least squares approach. When usi.g ei.her ghost centers or least squares, the random vari.ble shape parameter strategy results i. si.ni.i.antly better accuracy than when a constant shape parameter i. used.

关键词： Numeri.al Parti.l Di.ferenti.l Equati.ns Boundary Value Problems Radi.l Basi. Functi.n Methods Ghost Poi.ts Vari.ble Shape Parameter Least Squares

A Novel Approach for Developi.g a Li.ear Regressi.n Model wi.hi. Logi.ti. Cluster Usi.g Sci.i.-Learn

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Journal of Data Analysi. and i.formati.n Processi.g 2024年第3期12卷 348-369页

作者： Nwosu Ambrose Gi.bert i. O. Ai.ufua Choji.Davou Nyap Departments of Computer Sci.nces Nasarawa State University Keffi Nigeria Departments of Computer Sci.nces University of Jos Jos Nigeria

Due to the rapi. development of logi.ti. i.dustry, transportati.n cost i. also i.creasi.g, and fi.di.g trends i. transportati.n acti.i.i.s wi.l i.pact posi.i.ely i. i.vestment i. transportati.n i.frastructure. There i. li.i.ed li.erature and data-dri.en analysi. about trends i. transportati.n mode. Thi. thesi. delves i.to the operati.nal challenges of vehi.le performance management wi.hi. logi.ti.s clusters, a cri.i.al aspect of effi.i.nt supply chai. operati.ns. i. ai.s to address the i.sues faced by logi.ti.s organi.ati.ns i. opti.i.i.g thei. vehi.le fleets’ performance, essenti.l for seamless logi.ti.s operati.ns. The study’s core desi.n i.volves the development of a predi.ti.e logi.ti.s model based on regressi.n, focused on forecasti.g, and evaluati.g vehi.le performance i. logi.ti.s clusters. i. encompasses a comprehensi.e li.erature revi.w, research methodology, data sources, vari.bles, feature engi.eeri.g, and model trai.i.g and evaluati.n and F-test analysi. was done to i.enti.y and veri.y the relati.nshi.s between attri.utes and the target vari.ble. The fi.di.gs hi.hli.ht the model’s effi.acy, wi.h a low mean squared error (MSE) value of 3.42, i.di.ati.g i.s accuracy i. predi.ti.g performance metri.s. The hi.h R-squared (R2) score of 0.921 emphasi.es i.s abi.i.y to capture relati.nshi.s between i.put characteri.ti.s and performance metri.s. The model’s trai.i.g and testi.g accuracy further attest to i.s reli.bi.i.y and generali.ati.n capabi.i.i.s. i. i.terpretati.n, thi. research underscores the practi.al si.ni.i.ance of the fi.di.gs. The regressi.n-based model provi.es a practi.al soluti.n for the logi.ti.s i.dustry, enabli.g i.formed deci.i.ns regardi.g resource allocati.n, mai.tenance planni.g, and deli.ery route opti.i.ati.n. Thi. contri.utes to enhanced overall logi.ti.s performance and customer servi.e. By addressi.g performance gaps and embraci.g modern logi.ti.s technologi.s, the study supports the ongoi.g evoluti.n of vehi.le performance management

关键词： Mean Squared Error R2 Score F-Test MSE