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Comparative productivity of Prosopis cineraria and Tecomella undulata based ag.oforestry systems in deg.aded lands of Indian Desert

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Journal of Forestry Research 2009年第A2期20卷 144-150,I0003页

作者： g. singh Division of Forest Ecolog. Arid Forest Research Institute New Pali Road Jodhpur-342005 India

Tree-crop interactions were monitored by measuring.tree g.owth characters of Prosopis cineraria L. and Tecomella undulata L. and yields of Vig.a radiata （L） in ag.oforestry systems in deg.aded lands of Indian Desert. Potential competition for resource between the trees and associated crop was analyzed by measuring.soil water contents, soil org.nic matters and NH4-N at different depths of soil layers i.e., 0-25 cm, 25-50 cm and 50-75 cm in the experimental plots. The plots size were 16 m × 18 m （D1）, 20 m × 18 m （D2） and 32 m × 18 m （D3） with tree densities of 208, 138 and 104 ***^-1 after June 2002, respectively. Results showed that tree heig.t increased by 3% to 7% during.June 2002 to June 2004. Collar diameter increased by 30% and 11% in D1, 23% and 19% in D2 and 18% and 36% in D3 plots, respectively, in P. cineraria and T. undulata in two years period. The increase in crown diameter was 9% to 18% in P. cineraria and 11% to 16% in T. undulata. Tree g.owth was relatively g.eater in 2002 than in 2003. Yield of V. radiata increased linearly from D1 to D3 plots. Lowest soil water content at 1 m distance from tree base indicated g.eater utilization of soil water within the tree rooting.zone. Concentrations of soil org.nic matters and NH4-N were the hig.est （p〈0.05） in 0-25 cm soil layer. P. cineraria was more beneficial than T. undulata in improving.soil conditions and increasing.crop yield by 11.1% and thus more suitable for its integ.ation in ag.icultural land. The yield of ag.icultural crop increased when density of tree species was appropriate （i.e., optimum tree density）, thoug. it varied with tree size and depended upon resource availability. The result indicated bio-economic benefits of optimum density of P. cineraria and T. undulata over traditional practices of maintaining.random trees in farming.system in arid zones.

关键词： arid reg.on crop yield land productivity soil water and nutrients tree g.owth

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Effects of rainwater harvesting.on herbag. diversity and productivity in deg.aded Aravalli hills in western India

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Journal of Forestry Research 2011年第3期22卷 329-340页

作者： g. singh g.R. Choadhary B. Ram N.K. Limba Division of Forest Ecolog. Arid Forest Research Institute New Pali Road Jodhpur-342005 India

Over-exploitation and rural g.owth have severely damag.d native veg.tations of Aravalli hills in Rajasthan, India. This study was conducted to evaluate the effects of different restoration practices （i.e., rainwater harvesting.（RWH） and planting.of tree seedling.） on improve- ment in soil water and nutrients and g.owth and biomass of herbaceous veg.tation. Contour trench （CT）, g.adonie （g., Box trench （BT）, V-ditch （VD） and a control were imposed on 75 plots （each of 700 m 2 ） in natural slope g.adient defined as 10%, 10% 20% and 20% slopes in 2005. Each plot had three micro-sites of 1-m 2 at up （USP）, middle （MSP） and lower （LSP） part of the plot for observation in 2008. The existed g.adient （due to soil texture and topog.aphic features） of soil pH, EC, SOC, NH 4 - N, NO 3 -N and PO 4 -P in June 2005 between 20% to 10% slopes were decreased in 2008 after applying.RWH techniques. Such improvement in soil status promoted veg.tation g.owth and biomass in hig.er slope g.a- dients. Soil water, species diversity and herbag. biomass increased from USP to LSP, and RWH techniques had positive role in improving.SOC, nutrients, veg.tation population, evenness and g.owth at MSP. Despite of lowest SWC, reg.lar rain and g.eater soil water usag. enhanced g.een and dry herbag. biomasses in 10% 20% and 20% slopes, compared with 10% slope. The hig.est diversity in CT treatment was related to herbag. biomass, which was enhanced further by hig.est concentrations of SOC and PO 4 -P. Further, CT treatment was found to be the best treat- ment in minimizing.biomass variance in different slopes. Conclusively, soil texture and topog.aphic features controlled soil water and nutrients availability. Rainwater harvesting.techniques increased soil water storag. and nutrient retention and also enhanced veg.tation status and biomass by minimizing.the effects of hillslopes. Thus depending.upon the site conditions, suitable RWH technique could be adopted to increase herb- ag. biomass while rehabilit

关键词： herbag. g.owth and biomass hillslopes soil nutrients soil water dynamics veg.tation diversity

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Effect of varying.soil water stress reg.mes on nutrient uptake and biomass production in Dalberg.a sissoo seedling. in Indian desert

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Journal of Forestry Research 2009年第4期20卷 307-313,I0004,I0005页

作者： g. singh Bilas singh Division of Forest Ecolog. Arid Forest Research Institute

One-year-old seedling. of Dalberg.a sissoo from a sing.e provenance were planted in non-weig.ing.lysimeter tanks in July 1998 with a view to provide optimize irrig.tion parameters in desert areas. Varying.water reg.mes were maintained by re-irrig.ting.the seedling. at 36.2 mm （W1）, 26.5 mm （W2）, 20.2 mm （W3） and 18.1 mm （W4） treatments when the soil water content decreased to 7.56%, 5.79%, 4.44%, 3.23% in the respective treatments. Heig.t, collar diameter, number of leaves and leaf area were hig.est （p 〈 0.01） for the seedling. irrig.ted at W1 levek Above-mentioned g.owth parameters did not differ between W1 and W2 treatments but the seedling. in W2 level had hig.est biomass per liter of water use （i.e., water use efficiency, WUE）. Irrig.tion levels of W3 to W5 neg.tively affected seedling.g.owth, biomass production and nutrient accumulation. Soil water availability below W2 level （i.e., 5.79%） caused an increase in percentag. of root biomass to the total biomass of the seedling. However, there was a decrease in percentag. of leaf dry biomass in W3 and W4 treatments and in percentag. of stem dry biomass in the seedling. of W5 treatment. Seedling. in W5 treatment survived till at soil water potential of-1.96 MPa. Limitation of soil water availability in W3 and W4 treatments affected g.owth and biomass production of D. sissoo seedling.. W： level was best for g.owth and biomass production in which water use efficiency was hig.est. Therefore, better g.owth and biomass production of D. sissoo seedling. could be obtained by irrig.ting.the seedling. at soil water content of≥5.79% in the loamy sand soil.

关键词： arid reg.on irrig.tion levels seedling.survival: soil water content tree g.owth

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Double Neg.tive Left-Handed Metamaterials for Miniaturization of Rectang.lar Microstrip Antenna

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Journal of Electromag.etic Analysis and Applications 2010年第6期2卷 347-351页

作者： g. singh 不详

In this paper, I have explored a sig.ificant concept for the miniaturization of microstrip patch antenna config.ration by using.the double neg.tive (DNg. left-handed Metamaterials, which have dielectric permittivity and mag.etic permeability both neg.tive, simultaneously. It is achieved throug. the concept of phase-compensation by thin slab consist of the double positive (DPS) material, which have dielectric permittivity and mag.etic permeability both positive, simultaneously and DNg.metamaterials as a substrate of the microstrip patch antenna. By combining.the DNg.metamaterial slab with the slab made of DPS materials form a cavity resonator whose dispersion relation is independent of the sum of thickness of the slabs filling.this cavity but it depends on the ratio of their thicknesses. This cavity constitutes by DPS and DNg.material is used as substrate of the microstrip antennas and the DNg.material slab is behave as phase compensator.

关键词： Microstrip Antenna Phase Compensation Metamaterials Double Neg.tive Metamaterials

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Microstrip Antennas Loaded with Shorting.Post

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Eng.neering.科研） 2009年第1期1卷 41-45页

作者： Pradeep Kumar g. singh 不详

In this paper, a technical review with recent advances of the microstrip antennas loaded with shorting.posts is presented. The overall size of the antenna is sig.ificantly reduced by a sing.e shorting.posts and the ef... 详细信息

关键词： Microstrip Antennas Loading Shorting Post Efficiency g.in Bandwidth

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Model for Assessment of Child Mortality under Different Parity: A Bayesian Swatch

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Journal of Biosciences and Medicines 2019年第5期7卷 113-126页

作者： Arunabh Tripathi g. P. singh Abhinav singh NIIMH CCRAS Ministry of AYUSH Hyderabad India Department of Statistics and DST-CIMS BHU Varanasi India Department of Statistics University of Allahabad Allahabad India

In this study a model is conceptualized to measure the child mortality under different parity of women such that a better strateg. can be formulated to bring.down mortality rates. In the estimation of probability of child mortality some socio demog.aphic variables are taken in consideration. The estimates are obtained under Bayesian procedure. Two different models are formulated for it and model fitting.is observed by g.aphical approach along.with the chi square test. First model is betabinomial and second is binomial reg.ession model. Second model shows the better fit on the data. The estimate of probability of child mortality at hig.er parities namely, parity 3, parity 4 and parity 5 were obtained as 0.06, 0.09 and 0.13 respectively on the basis of the second model.

关键词： Child Mortality Model Fitting Bayesian Procedure

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Evaluation of trend in semen analysis for 11 years in subjects attending.a fertility clinic in India

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Asian Journal of Androlog. 2003年第3期5卷 221-225页

作者： P.Marimuthu M.C.Kapilashrami M.M.Misro g.singh National Institute of Health and Family Welfare Munirka New Delhi-110067 IndiaNational Institute of Health and Family Welfare Munirka New Delhi-110067 IndiaNational Institute of Health and Family Welfare Munirka New Delhi-110067 IndiaNational Institute of Health and Family Welfare Munirka New Delhi-110067 India

Aim: The data on semen analysis of subjects attending.the Fertility Clinic at NIHFW (National Institute of Health and Family Welfare) Munirka, New Delhi for the last 11 years were analyzed to verify the claims and speculations on declining.sperm counts in men. Methods: Approximately 10 % of the records every year starting.from 1990 to 2000 (numbering.1176 in total) were randomly selected for analysis. Subjects with azoospermia or severe olig.zoospermia were excluded from analysis. Results: The averag. ag. of the men attending.the infertility clinic was 31.2 years. The averag. semen volume and sperm count were found to be (2.6 ±0.1) mL and (60.6 ± 0.9) × 106/mL, respectively. No sig.ificant decline in sperm counts was observed in any year during.the entire study period. Only 1.8 % of the total number of sperm counts in the random sampling.were less then 20 × 106/mL. On the basis of WHO criteria on motility, the total percentag. of non-prog.essive and non-motile sperm in the ejaculate was hig.er (63 %) as compared to the combined categ.ries of slow and rapid linear prog.essive. Conclusion: The present study has confirmed similar finding. from other different countries that declining.sperm counts in humans is not a g.obal phenomenon.

关键词： semen analysis sperm motility declining.sperm count male infertility

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Efficient Location Services Using.Hierarchical Topolog. of Mobile Ad Hoc Networks

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Journal of Software Eng.neering.and Applications 2012年第1期5卷 14-20页

作者： Prasad Naik Hamsavath g. V. singh 不详

The thesis work was carried out in two phases. Firstly, we have desig.ed the Cluster-Based Object Location Alg.rithm (CBOLA) for finding.the object location in a cluster based network topolog.. Secondly, to take the advantag.s of clustering.architecture of Mobile Ad hoc Networks, we have especially desig.ed Object Location Clusters Alg.rithm (OLCA) for efficient Object Location manag.ment in MANET. Our comparison of simulation analysis shows that the CBOLA is more efficient and accurate in location information services and more robust than g.S and HRLS. In addition, we believe that our comparative study with the various location services schemes was facilitated accurate results in ad hoc networks. we are portioned our network area by desig.ing.a new clustering.alg.rithm called OLCA (Object Location Clusters Alg.rithm) for efficient object location in Mobile Ad hoc Networks. Simulation results and comparative analysis shows the performance and effectiveness of CBOLA and OLCA.

关键词： Location Clusters Objects Nodes MANET

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Numerical Computation of Resonant Frequency of Shorting.Post Loaded g.p-Coupled Circular Microstrip Patch Antennas

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Journal of Electromag.etic Analysis and Applications 2009年第4期1卷 259-264页

作者： Pradeep KUMAR g. singh T. CHAKRAVARTY 不详

In this paper, the numerical computation of resonant frequency of the two g.p-coupled circular microstrip patch antenna loaded with shorting.post by using.cavity model is presented. The numerically computed results are compared with simulated results. The two g.p-coupled circular microstrip patch antenna loaded with shorting.post miniaturize the cross-sectional dimension of the radiating.patch at the microwave frequency, which is useful for short rang. communications or contactless identification systems. The simulation has been performed using.method-of-moments based commercially available simulator IE3D.

关键词： g.p-Coupling Microstrip Antennas Shorting Post Resonant Frequency

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Bulk Viscous Anisotropic Cosmolog.cal Models with Dynamical Cosmolog.cal Parameters g.and ∧

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Natural Science 2015年第4期7卷 179-189页

作者： S. Kotambkar g. P. singh R. Kelkar Department of Mathematics Laxminarayan Institute of Technology Rashtrasant Tukadoji Maharaj Nagpur University Nagpur India Department of Mathematics Visvesvaraya National Institute of Technology Nagpur India Department of Mathematics S. B. Jain Institute of Technology Management and Research Nagpur India

This paper deals with the Bianchi type I anisotropic models of the universe, filled with a bulk viscous cosmic fluid, in the presence of variable g.avitational and cosmolog.cal constants. Some exact solutions of Einstein’s g.avitational field equations with bulk viscosity, g.avitational and cosmolog.cal constants have been obtained. Several well known forms of cosmolog.cal terms have been considered to discuss the effect of cosmolog.cal variables. The new cosmolog.cal models presented in this paper approaches to isotropic model with evolution of universe. The physical and dynamical properties of the models have also been discussed.

关键词： Bianchi Type-I Bulk Viscosity g.avitational and Cosmolog.cal “Constant”

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