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A CONTRIBUTION TO THE sCIENTIFIC FOUNDATIONs OF sYsTEMs ENGINEERING： sOLUTION sPACEs AND REQUIREMENTs

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Journal of systems science and systems Engineering 2017年第5期26卷 549-589页

作者： Alejandro salado Roshanak Nilchiani Dinesh verma Grado Department of Industrial and systems Engineering Virginia Tech Blacksburg VA 24061 USA school of systems and Enterprises Stevens Institute of Technology Hoboken N J 07030 USA

some researchers have suggested that scientific foundations expressed in a mathematical form are needed to thrust the success of systems engineering as a discipline on its own merit. In order to contribute the development of such systems science, this paper investigates from a foundational standpoint the relationships between stakeholder needs, system requirements, and sets of systems. Various theorems and corollaries are proposed and mathematically proven. The theoretical elements are presented as a foundation for the development of a science for requirements engineering. The proposed foundations are finally tested to mathematically describe, in a rigorous and precise manner, qualities of good requirements, which are otherwise traditionally defined using vague narrative. By showcasing practical examples of the theoretical aspects, the paper is intended to serve as a bridge between practitioners and theorists.

关键词： systems science systems theory requirements engineering mathematical formulation,requirements qualities formal concepts

Preparation by chemical co-precipitation, spectral and electrical characteristics of neodymium orthophosphate nanoparticles

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Journal of Rare Earths 2015年第5期33卷 535-544页

作者： seema verma K.K.Bamzai Crystal Growth and Material Research Laboratory Department of Physics & Electronics University of Jammu

Nanoparticles of neodymium orthophosphate （NdPO4） were prepared through a facile wet co-precipitation technique. The X-ray diffraction （XRD） studies revealed the material belonging to monoclinic monazite phase with crystallite size of 30.8 nm. scanning electron microscopic studies showed that the material was composed of a large number of agglomerated spherical particles having grain size of 92 nm. Thermogravimetric analysis suggested that the structural phase transition was seen above 800 °C. The spectroscopic investigations were carried out using Fourier transform infrared spectroscopy （FTIR）. UV-VIs-NIR ab-sorption spectrophotometer showed various transitions from the ground state 4I9/2 to various excited states within the 4f shell and the optical band gap came out to be 3.3 eV. The dielectric constant （ε′）, dielectric loss （tanδ） and ac conductivity ln（σac） were measured in the frequency range of 5 kHz to 1 MHz and in the temperature range of 40 to 500 °C. The dielectric measurement suggested that there was a shift in the value of transition temperature （Tc）, thereby indicating relaxor behaviour of the material. The activation energy value decreased with increase in frequency, thereby suggesting the role of mixed ionic-polaronic conduc-tivity.

关键词： nanoparticles spectroscopic dielectric properties rare earths

Endosulfan-mediated Biochemical Changes in the Freshwater Fish Clarias batrachus

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Biomedical and Environmental sciences 2004年第1期17卷 47-56页

作者： G.TRIPATHI PRIYANKA verma Department of Zoology J.N.V.UniversityJodhpur-342001IndiaDepartment of ZoologyJ.N.V.UniversityJodhpur-342001India

Objective Endosulfan is an extremely toxic organochlorine pesticide to aquatic organisms which might be hampering fish health through impairment of metabolism sometimes leading to death. so an experimental protocol was designed to look at endosulfan effects on a number of selected biochemical endpoints as well as to develop a mechanistic understanding of biochemical effects of endosulfan in freshwater fish. Methods The adult freshwater catfish Clarias batrachus were collected and acclimatized to laboratory condition for two weeks prior to experimentation. The toxicity bioassay test of commercial grade endosulfan (35% EC) was conducted for 21 days to determine its initial lethal concentration. The fish were exposed to sublethal concentration of endosulfan (0.06 mg/L) for 21 days. Pesticide - withdrawal experiments were also performed to study recovery. Protein synthesis inhibitors were injected to know the possible mechanism of recovery. The specimens of C. batrachus were sacrificed and brain, liver and caudal white skeletal muscle were removed. Tissues were homogenized and fractions were obtained by differential centrifugation. The activities of citrate synthase (Cs), glucose 6-phosphate dehydrogenase (G6-PDH) and lactate dehydrogease (LDH) were assayed spectrophotometrically. similarly, DNA, RNA and protein content were measured as per standard procedure. Results The exposure of sublethal concentration of endosulfan decreased the activity of citrate synthase (Cs) and glucose 6-phosphate dehydrogenase (G6-PDH) in the brain, liver and skeletal muscle of the freshwater catfish, C. batrachus. The brain lactate dehydrogenase (LDH) activity was also reduced in response to endosulfan toxicity. The maximum reduction in activities of these enzyme was 34%-43%. Withdrawal of endosulfan restored the enzyme activity to control level in all the three tissues. The recovery in enzyme activity appears to be due to dissociation of endosulfan or its metabolite(s) from the enzyme mole

关键词： Catfish Endosulfan Cs G6-PDH LDH DNA RNA RNA/DNA ratio and protein

Evaluation of groundwater quality using pollution index of groundwater(PIG) and non-carcinogenic health risk assessment in part of the Gangetic Basin

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Acta Geochimica 2021年第3期40卷 419-440页

作者： Apoorv verma N.B.singh Environmental science and Engineering Civil Engineering DepartmentInstitute of Engineering and TechnologyDr.A.P.J.Abdul Kalam Technical UniversityLucknow 226021India Harcourt Butler Technical University Kanpur 208002India

The aim of this study was to evaluate groundwater fitness for domestic and irrigational use in Unnao district of Uttar Pradesh,*** this study,block wise(n=16)groundwater samples were collected,and measured parameters were analyzed using the pollution index of groundwater(PIG),various irrigational indices,and graphical *** results of this study suggested that most of the parameters were within the prescribed limits of WHO and BIs,excluding F-(0.4 to 2.6 mg L^(-1))and Fe^(2+)(0.1 to 1.7 mg L^(-1)).Concentrations of total dissolved solids(TDs)were exceeded the desirable limit(>500 mg L^(-1))in 43.75%of samples at some *** Gibbs plot revealed that groundwater chemistry was governed by rock-water interaction in the region,especially silicate *** Piper plot suggested that Ca^(2+)-HCO3-is dominant hydrochemical facies in the area followed by mixed Ca^(2+)-Na^(+)-HCO_(3)^(-)type,Na^(+)-Cl^(-)type,and Na^(+)-HCO_(3)^(-)*** evaluation revealed that the contribution of F-and Fe2+in groundwater degradation is high in comparison to other elements in the region,about 18.75%samples showed low pollution,while about 6.25%samples shows moderate pollution,and 6.25%samples reflected high *** human health risk(HHR)assessment finding suggested that children(mean:1.36)are more vulnerable than adults(mean:1.01).sodium absorption ration(sAR),Residual sodium carbonate(RsC),and Permeability index(PI)indicated that most of the groundwater was suitable for irrigation,whereas,Magnesium hazard ration(MHR)and Potential salinity(Ps)indices suggested that only 37.5%and 56.25%of the samples were suitable for irrigational use,*** regional study would help in decision making for stakeholders and relevant authorities in the execution of groundwater management and remediation plans in the area.

关键词： Groundwater Pollution index of groundwater Irrigational indices silicate weathering Human health risk

Genotoxicity of vegetables irrigated by industrial wastewater

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Journal of Environmental sciences 2006年第5期18卷 964-968页

作者： Nupur Mathur Pradeep Bhatnagar Hemraj verma Environmental Molecular Microbiology Unit Department of Zoology University of Rajasthan Jaipur 302004 India.

Wastewater effluents from textile dyeing and printing industries of sanganer are discharged directly, without any treatment, into Amani shah Nallah drainage. The drainage water takes the dissolved toxicants to flora and fauna, including crops and seasonal vegetables, being grown in the land adjoining the Nallah drainage. Thus mutagenic potential of vegetables irrigated by the water of Amani shah Nallah drainage was investigated in the present study. The vegetables irrigated by ground water from sanganer have also been analyzed to determine possible adverse effects of these wastewater effluents on aqua duct.

关键词： sanganer textile wastewaters mutagenicity vegetables salmonella typhimurium: microsome bioassay

The tumor suppressor RAssF1A is a novel effector of small G protein Rap1A

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Protein & Cell 2011年第3期2卷 237-249页

作者： sunil K.verma Trivadi s.Ganesan Uday Kishore Peter J.Parker Department of Medical Oncology Medical Sciences DivisionThe University of OxfordOxford OX39DUUK Ovarian Cancer Group CRUK Molecular Oncology LaboratoriesWeatherall Institute of Molecular MedicineJohn Radcliffe HospitalHeadingtonOxford OX39DSUK Protein Phosphorylation Laboratory London Research InstituteCRUK Lincoln's Inn Fields Laboratories44 Lincoln's Inn FieldsLondon WC2A 3PXUK Kings College London The Division of Cancer StudiesSection of Cancer Cell Biology and Imaging2nd FloorNew Hunt's HouseGuy's HospitalSt Thomas StreetLondon SE11ULUK Current address:Center for Cellular and Molecular Biology Uppal RoadHyderabad 500007India Current address:Cancer Institute&Institute of Molecular Medicine Amrita Institute of Medical SciencesElamakkara P.O.KochiKerala 682026India Center for Infection Immunity and Disease MechanismsBiosciencesSchool of Health Sciences and Social CareBrunel UniversityUxbridge UB83PHWest LondonUK

Rap1A is a small G protein implicated in a spectrum of biological processes such as cell proliferation,adhesion,differentiation,and *** downstream effectors through which Rap1A mediates its diverse effects are largely *** we show that Rap1A,but not the related small G proteins Rap2 or Ras,binds the tumor suppressor Ras association domain family 1A(RAssF1A)in a manner that is regulated by phosphorylation of *** with Rap1A is shown to influence the effect of RAssF1A on microtubule behavior.

关键词： RAssF1A Rap1A microtubule vimentin protein-protein interaction

Global Annual Mean surface Air Temperature Anomalies and Their Link with Indian summer Monsoon Failures

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Advances in Atmospheric sciences 1990年第2期7卷 245-248页

作者： s.s.Dugam s.B.Kakade R.K.verma Indian Institute of Tropical Meteorology Pune-411005 IndiaIndian Institute of Tropical Meteorology Pune-411005 IndiaIndian Institute of Tropical Meteorology Pune-411005 India

Analysis of the global mean annual temperature anomalies based on land and marine data for the last 88 years (1901-1988) of this century has been carried out with a view to find any relationship with failures in Indian summer monsoon rainfall. On the climatological scale (i.e. 30 years) it has been noticed that there is an abnormal increase in the frequency of drought years during epochs of global warming and cooling, while it is considerably less when global temperatures are near normal. Results are unchanged even when the data are filtered out for ENsO (El-Nino southern Oscillation) *** has also been noticed that during warm and cold epochs in global temperatures the amount of summer monsoon rainfall decreases as compared to the rainfall during a normal temperature epoch.

关键词： In Global Annual Mean surface Air Temperature Anomalies and Their Link with Indian summer Monsoon Failures ENsO Mean

Fuzzy computational study on the generalized fractional smoking model with caputo gH-type derivatives

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International Journal of Biomathematics 2024年第4期17卷 151-194页

作者： Lalchand verma Ramakanta Mehert Department of Mathematics&Humanities s.V.National Institute of Technology Surat-395007India

This work considers a generalized fuzzy fractional smoking model with Caputo gHtypes fractional derivatives upon considering the case of uncertainty *** disease-free equilibrium point and stability of the equilibrium point have been discussed for the fuzzy nonlinear fractional smoking *** analytical proofs for the existence and uniqueness of the proposed model are concerned with the help of the fixed-point theorem,Banach contraction,and schauder theorem.A robust double parametric approach with a generalized transform is used to study the behavior of the fuzzy fractional model in an uncertain context and obtain the convergence analysis of the study in a crisp ***,the obtained results of the proposed model have been validated with the Runge-Kutta method of fourth order in crisp case(s=1,l=O).

关键词： Caputo fractional derivative triangular fuzzy number smoking model q-HAshTM convergence analysis

Axially Oriented structured Porous Layers for Heat Transfer Enhancement in a solar Receiver Tube

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Journal of Thermal science 2021年第5期30卷 1643-1657页

作者： DAs shefali verma Neha PATHAK Manabendra BHATTACHARYYA suvanjan Department of Mechanical Engineering Indian Institute of Technology PatnaPatna801103BiharIndia Department of Mechanical Engineering BITS-PilaniPilani333031RajasthanIndia

The present work reports a numerical investigation of heat transfer and pressure drop characteristics in a solar receiver tube with different shaped porous media for laminar and low Reynolds number turbulent flow *** simulations have been performed with finite volume-based code ANsYs(v-2017)for different shapes of porous layers axially oriented in the *** plain-shaped porous medium fitted up to 50%of the tube shows better performance than other-shaped porous *** have also been performed for axially oriented structured porous media with different *** oriented structured porous medium develops a lateral flow disturbance enhancing the intermixing of the liquid and porous medium at their *** porous medium with a 3-crest configuration shows the best heat transfer performance among all the shapes of porous *** offers a maximum of 148%heat transfer enhancement compared to a half-filled plain porous layer,whereas it reports a maximum of 564%enhancement compared to the flow without a porous *** lateral flow tendency or the swirling effect helps better heat transfer performance in the axially oriented structured porous *** evaluation criterion(PEC)in all types of porous media is more in the transitional flow regime than in the laminar and turbulent flow *** the same operating conditions,the maximum value of the PEC in the present work is 120%higher than the maximum value of PEC for other-shaped porous media reported in the *** for Nusselt number have been developed for both laminar and turbulent flow regimes for three crests shaped porous medium.

关键词： porous medium structured porous layer heat transfer enhancement pressure drop performance evaluation criterion