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Fault Locator Using Two-end Unsynchronized measurements for UHV Series Compensated Double-circuit Lines

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高电压技术 2008年第12期34卷 2523-2529页

作者： m. Fulczyk P. Balcerek J. Izykowski E. Rosolowski m. m. saha ABB Corporate Research Center Starowislna 13A 31-038 Krakow Poland Wroclaw University of Technology Wyspianskiego 27 50-370 Wroclaw Poland ABB AB SE 721 59 Vasteras Sweden

An accurate fault location algorithm for double-circuit series compensated lines is *** of two-end unsynchronized measurements of current and voltage signals is *** algorithm applies two subroutines,designated for locating faults on particular line sections,and additionally the procedure for selecting the valid *** subroutines are formulated with use of the generalized fault loop model and the distributed parameter line model is *** ATP-EmTP based evaluation has shown the validity of the derived fault location algorithm and its high accuracy.

关键词：两端非同步测量法串联补偿线路故障定位仪 ATP-EmTP

Combined effect of Reynolds and Grashof numbers on mixed convection in a lid-driven T-shaped cavity filled with water-Al_2O_3 nanofluid

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Journal of Hydrodynamics 2015年第5期27卷 782-794页

作者： mOJUmDER Satyajit saha Sourav saha Sumon mAmUN m.A.H. Department of mechanical Engineering Bangladesh University of Engineering and Technology

Lid-driven mixed convection has been given immense importance due to its wide range of applications. A T-shaped cavity is introduced and pertinent parameters controlling mixed convection phenomenon are analyzed in this paper. Water-Al2O3 nanofluid is considered inside the cavity to augment heat transfer rate. Galerkin weighted residual method of finite element analysis is applied for the numerical simulations. Numerical solution is obtained for different solid volume fractions of nanofluid（？= 0- 0.15）, Grashof numbers（Gr= 0.1 ？5 000） and Reynolds numbers（Re= 0.31 ？1 000） in laminar flow regime. Special attention is given on the analysis of flow at the pure mixed convection regime. It is found that Grashof, Reynolds and Richardson numbers along with solid volume fraction of nanofluid have significant effect on heat transfer characteristics inside the cavity. Results are presented using streamline and isotherm contours along with related variation of average Nusselt numbers of the heated wall and average fluid temperature inside the cavity.

关键词： mixed convection nanofluid lid-driven T-shaped Richardson number finite element

Field-dependent spin waves in high-aspect-ratio singlecrystal ferromagnetic nanowires

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Nano Research 2016年第5期9卷 1426-1433页

作者： Semanti Pal Susmita saha m. Venkata Kamalakar Anjan Barman Department of Condensed matter Physics and material Sciences S. N. Bose National Centre for Basic Sciences Block JD Sector Ⅲ Salt Lake Kolkata 700 098 India Department of Physics and Astronomy Uppsala University Box 516 75120 Uppsala Sweden

We investigate the spin wave （SW） modes in high-aspect-ratio single-crystal ferromagnetic nanowires （FmNWs） using an all-optical time-resolved magnetooptical Kerr effect （TR-mOKE） microscope. The precessional magnetization dynamics in such FmNWs unveil the presence of uniform and quantized SW modes that can be tuned by varying the bias magnetic field （H）. The frequencies of the modes are observed to decrease systematically with a decreasing magnetic field, and the number of modes in the spectrum is reduced from four to three for H 〈 0.7 kOe. To understand these results, we perform micromagnetic simulations that reveal the presence of edge, standing wave, and uniform SW modes in the nanowires （NWs）. Our simulations clearly show how the standing wave and uniform SW modes coalesce to form a single mode with uniform precession over the entire NW for H 〈 0.7 kOe, reproducing the experimentally observed reduction in modes. Our study elucidates the possibility of manipulating the SW modes in magnetic nanostructures, which is useful for applications in magnonic and spintronic devices.

关键词： Field-dependent high-aspect-ratio nanowires

Group planting of cherry (Prunus avium L.) fosters growth and tree quality is superior to conventional row planting in Germany

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Journal of Forestry Research 2018年第4期29卷 1088-1099页

作者： Somidh saha Institute for Technology Assessment and Systems Analysis (ITAS) Karlsruhe Institute of Technology (KIT) Karlstr. 11 76133 Karlsruhe Germany Institute of Forest Sciences University of Freiburg Freiburg Germany

Wild cherry trees produce high-quality timber and provide multiple ecosystem services. However, planting and tending cherry stands in conventional rows are too costly. Therefore, low density group planting was trialled as an alternative to row planting. The mortality, growth, and quality of planted cherry trees were compared between the group and row planting. The influence of neighbourhood competition and light availability on growth and quality was studied. The group and row planting of cherry trees were established at a wind-thrown site in southwestern Germany in the year 2000. In group planting, five cherry seedlings and seven lime seedlings （Tilia cordata mill.） were planted with a 1 x 1 m spacing. In total, 60 groups were planted per hectare with a 13 × 13 m spacing. In contrast, 3300 seedlings （2475 cherries and 825 limes） were planted per hectare in row planting with a 3 × 1 m spacing. Ten groups and plots （10 × 10 m） were randomly established in group and row planting stand, respectively. The survival rate, stability （height to diameter ratio）, diameter, and height growth were significantly higher in group planting. In the group plantings,40.5% of cherry trees had straight stems and 13.5% had a monopodial crown compared with 15% with straight stems and 2% with a monopodial crown in row planting. The proportion of dominant cherry trees in canopy was 49% in groups compared with 22% in rows. The length of branch free bole was significantly higher in cherries planted in groups than those grown in rows. Intra- and interspecific competition reduced the growth and stability of cherry trees in row planting, but not in group planting. Light availability did not cause any significant effects on growth and quality between group and row planting. This first study on cherry group planting indicates that the survival rate, growth, and tree quality were higher in groups than in rows at this early development stage. The competition by naturally born seedlings was an import

关键词： Group planting Tree growth Tree quality Interspecific competition Intraspecific competition Photosynthetically active photon flux density Total sitefactor

Large soft-sediment deformation structures(SSDS) in the Permian Barren measures Formation, Pranhita-Godavari Valley, India:potential link to syn-rift palaeoearthquake events

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Journal of Palaeogeography 2020年第2期9卷 198-215页

作者： Biplab Bhattacharya Abhirup saha Department of Earth Sciences Indian Institute of TechnologyRoorkee 247667India

Records of palaeoearthquakes in sedimentary rocks are often debated due to the potential confusion in distinguishing seismic versus aseismic trigger mechanisms causing *** present paper documents some unique soft-sediment deformation structures(SSDS),characterized by their extremely large size,complex morphology and preservation in coarse-grained pebbly *** SSDS are present in the Permian Barren measures Formation,a syn-rift depositional unit within the Lower Gondwana succession in the Pranhita-Godavari Valley,eastern Peninsular ***^210 m thick succession is represented by stacked fining-up retrogradational cycles,characterized by coarse-grained trough cross-stratified pebbly sandstones near the base and fine-grained heterolithic sandstones–mudstones at the *** cycle signifies a change from fluvial-to tidal-influenced depositional ***-grained pebbly sandstone beds near the base of each cycle record most SSDS,including complexly deformed layers,pseudonodules,load and flame structures,various water-escape structures like vertical/inclined sediment columns(sedimentary dykes)and contorted beds,and syn-sedimentary *** deformed beds are underlain and overlain by the undeformed *** deformed SSDS are often sharply truncated at the top by undeformed beds manifesting syn-sedimentary character,which signifies that deformation took place just after deposition of the affected beds,but before deposition of the overlying beds while sedimentation was *** analysis reveals the absence of processes like storms/pounding waves,slumps,rapid dumping(massive beds),impact shaking,volcanisms,tsunami waves or sediment gravity flows in the study area,thus negating their possibility as triggering agents for the *** complex nature and large size of the deformation structures imply extensive liquefaction near the sediment–water *** addition,the deformed beds comply with most of the criteria of typic

关键词： Large SSDS Seismites Fluvial-tidal Syn-rift Gondwana Permian

Irritable bowel syndrome: Pathogenesis, diagnosis, treatment, and evidence-based medicine

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World Journal of Gastroenterology 2014年第22期20卷 6759-6773页

作者： Lekha saha Department of Pharmacology Post Graduate Institute of Medical Education and ResearchChandigarh 160012India

Irritable bowel syndrome (IBS) is a chronic and debilitating functional gastrointestinal disorder that affects 9%-23% of the population across the world. The percentage of patients seeking health care related to IBS approaches 12% in primary care practices and is by far the largest subgroup seen in gastroenterology clinics. It has been well documented that these patients exhibit a poorer quality of life and utilize the health care system to a greater degree than patients without this diagnosis. The pathophysiology of IBS is not clear. many theories have been put forward, but the exact cause of IBS is still uncertain. According to the updated ROmE III criteria, IBS is a clinical diagnosis and presents as one of the three predominant subtypes: (1) IBS with constipation (IBS-C); (2) IBS with diarrhea (IBS-D); and (3) mixed IBS (IBS-m); former ROmE definitions refer to IBS-m as alternating IBS (IBS-A). Across the IBS subtypes, the presentation of symptoms may vary among patients and change over time. Patients report the most distressing symptoms to be abdominal pain, straining, myalgias, urgency, bloating and feelings of serious illness. The complexity and diversity of IBS presentation makes treatment difficult. Although there are reviews and guidelines for treating IBS, they focus on the efficacy of medications for IBS symptoms using high-priority endpoints, leaving those of lower priority largely unreported. Therefore, the aim of this review is to provide a comprehensive evidence-based review of the diagnosis, pathogenesis and treatment to guide clinicians diagnosing and treating their patients.

关键词： Irritable bowel syndrome Pathogenesis Diagnosis Treatment Evidence-based medicine

Effect of Hall current on mHD natural convection flow from vertical permeable flat plate with uniform surface heat flux

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Applied mathematics and mechanics(English Edition) 2011年第9期32卷 1127-1146页

作者： L.K.saha S.SIDDIQA m.A.HOSSAIN Department of mathematics University of DhakaDhaka 1000Bangladesh Department of mathematics COMSATS Institute of Information TechnologyPark RoadChak ShahzadIslamabad 44000Pakistan

The effect of the Hall current on the magnetohydrodynamic （mHD） natural convection flow from a vertical permeable flat plate with a uniform heat flux is analyzed in the presence of a transverse magnetic *** is assumed that the induced magnetic field is negligible compared with the imposed magnetic *** boundary layer equations are reduced to a suitable form by employing the free variable formulation （FVF） and the stream function formulation （SFF）.The parabolic equations obtained from FVF are numerically integrated with the help of a straightforward finite difference ***,the nonsimilar system of equations obtained from SFF is solved by using a local nonsimilarity method,for the whole range of the local transpiration parameter ζ.Consideration is also given to the regions where the local transpiration parameter ζ is small or large ***,in these particular regions,solutions are acquired with the aid of a regular perturbation *** effects of the magnetic field m and the Hall parameter m on the local skin friction coefficient and the local Nusselt number coefficient are graphically shown for smaller values of the Prandtl number P r （= 0.005,0.01,0.05）.Furthermore,the velocity and temperature profiles are also drawn from various values of the local transpiration parameter ζ.

关键词： magnetohydrodynamic (mHD) natural convection Hall current permeable plate heat flux

Hydrogen Adsorption on metal-Organic Framework mOF-177

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Tsinghua Science and Technology 2010年第4期15卷 363-376页

作者： Dipendu saha Chemical Engineering Department New Mexico State University

This review summarizes the recent literature on the synthesis, characterization, and adsorption properties of meal-organic framework mOF-177. mOF-177 is a porous crystalline material that consists of Zn40 tetrahedrons connected with benzene tribenzoate （BTB） ligands, It is an ideal adsorbent with an ex- ceptionally high specific surface area （BET〉4500 m^2/g）, a uniform micropore size dJstrJbutJon with a median pore diameter of 12.7 A, a large pore volume （2.65 cm^3/g）, and very promising adsorption properties for hy- drogen storage and other gas separation and purification applications. A hydrogen adsorption amount of 19.6 wt.% on mOF-177 at 77 K and 100 bar was observed, and a CO2 uptake of 35 mmol/g on mOF-177 was measured at 45 bar and an ambient temperature. Other hydrogen properties （kinetics and heat of ad- sorption） along with adsorption of other gases including CO2, CO, CH4, and N2Oon mOF-177 were also be discussed. It was observed in experiments that mOF-177 adsorbent tends to degrade or decompose when it is exposed to moisture. Thermogravimetric analysis showed that the structure of mOF-177 remains intact at temperatures below 330℃ under a flow of oxygen, but decomposes to zinc oxide at 420℃.

关键词： metal-organic framework mOF-177 adsorption hydrogen storage

Kinetics of phenol and m-cresol biodegradation by an indigenous mixed microbial culture isolated from a sewage treatment plant

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Journal of Environmental Sciences 2008年第12期20卷 1508-1513页

作者： Pichiah Saravanan Kannan Pakshirajan Prabirkumar saha Department of Chemical Engineering Indian Institute of Technology GuwahatiGuwahati Department of Biotechnology Indian Institute of Technology GuwahatiGuwahati

An acclimatized mixed microbial culture,predominantly Pseudomonas sp.,was enriched from a sewage treatment plant,and its potential to simultaneously degrade mixtures of phenol and m-cresol was investigated during its growth in batch shake flasks.A 22 full factorial design with the two substrates at two different levels and different initial concentration ranges(low and high),was employed to carry out the biodegradation *** substrates phenol and m-cresol were completely utilized within 21 h when ...

关键词： biodegradation factorial design of experiments kinetics m-cresol mixed microbial culture phenol sum kinetics model