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Image processing algorithms for in-field cotton boll detection in natural lighting conditions

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Artificial Intelligence in Agriculture 2021年第1期5卷 142-156页

作者： Naseeb Singh V.K.tewari P.K.Biswas C.M.Pareek L.K.Dhruwa Department of Agricultural and Food Engineering IIT KharagpurKharagpur 721302India Department of Electronics and Electrical Communication Engineering IIT KharagpurKharagpur 721302India

In developing countries,the cotton harvesting operation is currently being performed *** to the monotonous nature of this task and the involvement of a considerable amount of labor,this operation becomes very tedious and *** harvesting robots can be a good alternative for the selective picking of cotton bolls from the *** this study,an attempt has been made to develop the image processing algorithms for in-field cotton boll detection in natural lighting conditions for the cotton harvesting *** image processing algorithms namely color difference,band ratio,YCbCr method,and chromatic aberration were proposed for the real-time segmentation of cotton bolls under natural outdoor light *** performance of developed image processing algorithms was evaluated and the experimental results revealed that the chromatic aberration method outperforms as compared to other developed *** chromatic aberration method showed the highest identification rate of 91.05%with false positive and false negative rates of 6.99%and 4.88%respectively,among all the proposed *** highest sensitivity and specificitywere found to be 81.31%and 97.53%,respectively,using the chromatic aberration ***,the chromatic aberration approach demonstrated a very promising performance for in-field cotton bolls detection under natural lighting conditions which confirms its applicability for the robotic cotton harvesters.

关键词： Cotton recognition Image segmentation Color models Color thresholding

Early Pliocene Paleoceanography of the Vityaz Fracture Zone,Central Indian Ridge

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Acta Geologica Sinica(English Edition) 2007年第4期81卷 614-621页

作者： M.V.S.GUPTHA Ranadip BANERJEE Lina P.MERGULHAO Priyanka BANERJEE G.PARTHIBAN Manish tewari National Institute of Oceanography Dona Paula Goa-403 004India Department of Geological Sciences Jadavpur University Kolkata700032India Physical Research Laboratory Navrangpura AhmedabadIndia

Planktic foraminifera from the calcareous substrate of a ferromanganese crust in the Vityaz Fracture Zone （VFZ）, Central Indian Ridge were studied to reconstruct the early Pliocene paleoceanography of this region. Eleven species of planktic foraminifera were encountered, among them Globorotalia menardii, Neogloboquadrina dutertrei, Globigerina bulloides and Globigerinoides tuber are prominent. Predominance of N. dutertrei in the top 3 cm of the carbonate substrate is attributed to an influx of fresh water which eventually triggered their productivity by increasing the nutrient level. The presence of G. bulloides and G. menardii in significant proportions in deeper layers suggests the prevalence of open ocean upwelling. The bulk chemical compositions of the substrate at different depth intervals indicates higher enrichment of trace metals in the upper sections which could have been supplied through oceanic water by the chemical weathering of terrestrial matter during the peak of Pliocene Asian monsoon. Thus, it is concluded that during the early Pliocene the biogenic components of the substrate were distinctly contributed by both upwelling and productivity triggered by an influx of fresh water originating from the intensification of the Asian monsoon during the early Pliocene Period.

关键词： Central Indian Ridge Vityaz Fracture Zone ferromanganese crust biogenic bloom,freshwater influx Neogene climate change spores Asian monsoon

mpaired flow-mediated vasodilatation in Asian Indians with erectile dysfunction

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Asian Journal of Andrology 2013年第5期15卷 652-657页

作者： Tanuj Bhatia Aditya Kapoor Jatinder Kumar Archana Sinha Priyadarshi Ranjan Sudeep Kumar Naveen Garg Satyendra-tewari Aneesh Srivastava Rakesh Kapoor Pravin K Goel Departments of Cardiology Sanjay Gandhi PGIMS Lucknow 226014 India Urology and Renal Transplantation Sanjay Gandhi PGIMS Lucknow 226014 India

Endothelial dysfunction is the postulated link between coronary artery disease （CAD） and erectile dysfunction （ED）. Brachial artery flow-mediated vasodilatation （FMD） is a non-invasive surrogate marker for endothelial function assessment. Despite Asian Indians representing a considerable global CAD burden, data on FMD and ED in these patients are lacking. Of the 225 patients undergoing coronary angiography, 72% had ED （assessed using the International Index of Erectile Function （IIEF-5） questionnaire）; ED was moderate to severe in 61% of the patients. ED patients had a higher incidence of severe and diffuse angiographic CAD, a greater number of coronary vessels involved and a lower mean brachial artery FMD （6.40%±4.60% vs. 9.10%±4.87%, P〈0.001） compared to non-ED patients. A progressive reduction in FMD was noted with increasing severity of ED. Impaired FMD （ ≤ 5.5%） was twice as common in ED patients （52% vs. 24% without ED）. Patients with impaired FMD had higher ED prevalence （85% vs. 62%） and lower mean I IEF-5 scores compared to those with normal FMD. Impaired FMD was a significant ED predictor independent of other risk factors （odds ratio, 2.33; 95% confidence interval： 0.59-9.23; P=0.03）. An inverse correlation between FMD and ED severity was observed （r=-0.22; P=0.004）. ED is common among Asian Indians with angiographically documented CAD. Patients with ED have impaired FMD independent of other risk factors, suggesting that endothelial dysfunction is the underlying pathophysiology. Urologists and cardiologists need to be aware of the association between ED, CAD and endothelial dysfunction.

关键词： Asian Indians brachial artery flow mediated vasodilatation erectile dysfunction (ED)

The surgical learning curve for robotic-assisted laparoscopic radical prostatectomy： experience of a single surgeon with 500 cases in Taiwan, China

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Asian Journal of Andrology 2014年第5期16卷 728-734,I0009页

作者： Yen-Chuan OU Chun-Kuang Yang Kuangh-Si Chang John Wang Siu-Wan Hung Min-Che Tung Ashutosh K tewari Vipul R Patel Division of Urology Department of Surgery Taichung Veterans General Hospital Taichung Taiwan China School of Medicine National Yang-Ming University Taipei Taiwan China Department of Research Taichung Veterans General Hospital Taichung Taiwan China Department of Pathology Taichung Veterans General Hospital Taichung Taiwan China Department of Radiation Taichung Veterans General Hospital Taichung Taiwan China Division of Urology Department of Surgery Tungs' Taichung MetroHarbor Hospita Taichung Taiwan China New York Presbyterian Hospital Weill Cornell Medical College New York NY USA Global Robotics Institute Florida Hospital Orlando Florida USA

To analyze the learning curve for cancer control from an initial 250 cases （Group I） and subsequent 250 cases （Group II） of robotic-assisted laparoscopic radical prostatectomy （RALP） performed by a single surgeon. Five hundred consecutive patients with clinically localized prostate cancer received RALP and were evaluated. Surgical parameters and perioperative complications were compared between the groups, Positive surgical margin （PSM） and biochemical recurrence （BCR） were assessed as cancer control outcomes. Patients in Group II had significantly more advanced prostate cancer than those in Group I （22.2% vs 14.2%, respectively, with Gleason score 8-10, P = 0.033; 12.8% vs 5.6%, respectively, with clinical stage T3, P = 0.017）. The incidence of PSM in pT3 was decreased significantly from 49% in Group I to 32.6% in Group Ih A meaningful trend was noted for a decreasing PSM rate with each consecutive group of 50 cases, including pT3 and high-risk patients. Neurovascular bundle （NVB） preservation was significantly influenced by the PSM in high-risk patients （84.1% in the preservation group vs 43.9% in the nonpreservation group）. The 3-year, 5-year, and 7-year BCR-free survival rates were 79.2%, 75.3%, and 70.2%, respectively. In conclusion, the incidence of PSM in pT3 was decreased significantly after 250 cases. There was a trend in the surgical learning curve for decreasing PSM with each group of 50 cases. NVB preservation during RALP for the high-risk group is not suggested due to increasing PSM.

关键词： cancer control learning curve prostate cancer prostatectomy robotics surgical margin

Well Behaved Class of Charge Analogue of Adler’s Relativistic Exact Solution

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Journal of Modern Physics 2011年第6期2卷 481-487页

作者： Mamta Joshi Pant Bipin Chandra tewari 不详

We present a well behaved class of charge analogue of Alder’s (1974). This solution describes charge fluid balls with positively finite central pressure and positively finite central density;their ratio is less than one and causality condition is obeyed at the centre. The outmarch of pressure, density, pressure-density ratio and the adiabatic speed of sound is monotonically decreasing, however, the electric intensity is monotonically increasing in nature. The solution gives us wide range of parameter K (0.96 ≤ K ≤ 5.2) for which the solution is well behaved and appropriate for relativistic theory;therefore, suitable for modeling of super dense star. For this solution the mass of a star is maximized with all degrees of suitability and by assuming the surface density ρb = 2 × 1014 g/cm3. Corresponding to K = 0.96 and X = 0.35, the maximum mass of the star comes out to be 3.43 MΘ with linear dimension 32.66 Km and central redshift and surface redshift 1.09374 and 0.5509 respectively.

关键词： Charge Fluid Reissner-Nordstrom General Relativity Exact Solution

Cross Layer Design for Cooperative Transmission in Wireless Sensor Networks

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Wireless Sensor Network 2011年第6期3卷 209-214页

作者： Kanojia Sindhuben Babulal Rajiv Ranjan tewari 不详

Several protocols and schemes have been proposed to reduce energy consumption in Wireless Sensor Net-works (WSNs). In this paper we employ farcoopt, a cross layer design approach with the concept of coop-eration among the nodes with best farthest neighbor scheme to increase the Quality of Service (QoS), reduce energy consumption, increases performance and end-to-end throughput. We present cooperative transmission to connect previously disconnect parts of a network thus overcoming the separation problem of multi-hop network. We show that this approach improves connectivity over 50% compared to multi-hop approaches and reduces the number of nodes necessary to provide full coverage of an area up to 35%. Simulation results show that on increase of data rates i.e. packet the network life time increases in farcoopt as compared to tra-ditional multi hop approach. The result of this analysis is presented in this work.

关键词： Cooperative Network Cross Layer Design Wireless Sensor Networks Energy Saving Communication Protocol Routing

Seasonal effect on rooting behaviour of important bamboo species byculm cuttings

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Journal of Forestry Research 2012年第3期23卷 441-445页

作者： Y.A.Gulabrao R Kaushal S.K.tewari J.M.S.Tomar O.P.Chaturvedi G.B.Pant University of Agriculture&Technology Pantnagar 263145India Central Soil and Water Conservation Reserach&Training Institute Dehradun 248195India

We investigated the influence of season on the rooting be- haviour of eight important bamboo species viz., Bambusa balcooa, B. bambos, B. nutans, B. tuMa, B. vulgaris, Dendrocalamus giganteus, D. hamiltonii and D. strictus. We collected 2-3 node culm cuttings in three growing seasons viz. spring （March）, summer （June） and rainy （August） from superior candidate plus clumps （CPCs） centralized in the germplasm garden. Cuttings were placed horizontally in sand and were provided with intermittent misting at regular intervals. Bamboo species exhibited differential rhizogenesis behavior in different seasons. The study reveals significant variation in sprouting and rooting behaviour in different bamboo species. B. bambos had maximum rooting （78.89%）, followed by B. vulgaris （74.44%）. In general, the potential of different bamboo species for rooting was found to be in the order： B. bambos 〉 B. vulgaris 〉 B. balcooa 〉 D. hamiltonii 〉 B. tulda 〉 D. strictus 〉 D. giganteus 〉B. nutans. The maximum rooting was recorded in spring （56.67%）, which was closely followed by summer （54.58%）. In winter season, minimum rooting （36.67%） was observed. The interaction effect of species x season was also significant on sprouting and rooting pa- rameters. In B. balcooa, B. nutans, B. vulgaris, D. hamiltonii and D. strictus, cuttings collected in summer season showed maximum sprouting and rooting, whereas, B. bambos, B. tulda and D. giganteus had maximum rooting in spring. The maximum number of roots developed per cutting was observed in B. tulda （43.8） during spring season.

关键词： bamboos culm cutting rooting season sprouting

Influence of C-Axis Inter Unit Cell Resonant Tunneling on the Spectral Function in Bilayer Cuprates

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Journal of Modern Physics 2011年第7期2卷 759-765页

作者： Ajay - B. S. tewari Govind - 不详

The role of intra unit cell coupling along with inter unit cell resonant tunneling between the copper-oxygen planes on the electronic spectral function in normal state of bilayer high Tc cuprates like Bi2Sr2CaCu2O8+x is investigated. The Hubbard model including terms representing hopping between the planes within the unit cell, and resonant tunneling between the planes in two adjoining cells is used along with the Green’s function equation of motion approach to obtain an expression of spectral function. The spectral function at (π,0) point of the Brillouin zone is numerically calculated. It is found that the intra unit cell coupling lead to splitting of spectral peak especially close to (π,0) point, while the inter unit cell resonant tunneling lead to a broadening in the spectral function and suppression of bilayer splitting in the normal state. In the presence of finite electron correlations the inter unit cell tunneling induce strong broadening in the spectral features. The electron correlations and inter unit cell tunneling is important in determining the shape of the spectral function in doped bilayer cuprates. These results are viewed in terms of the existing ARPES measurements on bilayer cuprates.

关键词： Multilayer Superconductors Electronic Structure Strongly Correlated Systems

Dissipative Spherical Gravitational Collapse of Isotropic Fluid

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Journal of Modern Physics 2015年第4期6卷 453-462页

作者： B. C. tewari Kali Charan Department of Mathematics Kumaun University S.S.J. Campus Almora India

We present a number of parametric class of exact solutions of a radiating star and the matching conditions required for the description of physically meaningful fluid. A number of previously known class of solutions have been rediscovered which describe well behaved nature of fluid distributions. The interior matter fluid is shear-free spherically symmetric isotropic and undergoing radial heat flow. The interior metric obeyed all the relevant physical and thermodynamic conditions and matched with Vaidya exterior metric over the boundary. Initially the interior solutions represent a static configuration of perfect fluid which then gradually starts evolving into radiating collapse. The apparent luminosity as observed by the distant observer at rest at infinity and the effective surface temperature are zero in remote past at the instant when collapse begins and at the stage when collapsing configuration reaches the horizon of the black hole.

关键词： Exact Solutions Radiating Star Gravitational Collapse Black Hole