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New dynamic permeability upscaling method for flow simulation under depletion drive and no-crossflow conditions

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Petroleum Science 2013年第2期10卷 233-241页

作者： Mohammad Sharifi Mohan kelkar McDougall School of Petroleum Engineering The University of Tulsa800 South Tucker DriveTulsaOklahoma74104United States

The main purpose of upscaling in reservoir simulation is to capture the dynamic behavior of fine scale models at the coarse scale. Traditional static or dynamic methods use assumptions about the boundary conditions to determine the upscaled properties, in this paper, we show that the upscaled properties are strongly dependent on the flow process observed at the fine scale. We use a simple no- crossflow depletion drive process and demonstrate that an upscaled property is not a constant value. Instead, if the goal is to match the performance of the fine scale model, the upscaled permeability changes with time. We provide an analytical solution to determine the upscaled permeability and present the value of upscaled permeability under limiting conditions. Our equation suggests that it is possible that upscaled value can fall outside the range of fine scale values under certain conditions. We show that for pseudo steady state flow, using common averaging methods like arithmetic or even geometric averaging methods can lead to optimistic results. We also show that the no-crossflow solution is significantly different than crossflow solution at late times. We validate our method by comparing the results of the method with flow simulation results in two and multi-layered models.

关键词： Upscaling permeability reservoir simulation no-crossflow depletion drive

Anisotropic Bianchi Type Ⅰ Cosmological Models with Generalized Chaplygin Gas and Dynamical Gravitational and Cosmological Constants

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Communications in Theoretical Physics 2017年第2期67卷 222-230页

作者： S.Kotambkar G.P.Singh R.kelkar Binaya K.Bishi Department of Applied Mathematics LIT RTM Nagpur University Nagpur India Department of Mathematics VNIT Nagpur India Department of Applied Mathematics SB Jain ITMR Nagpur India

This paper deals with study of generalized Chaplygin gas model with dynamical gravitational and cosmological constants. In this paper a new set of exact solutions of Einstein field equations for spatially homogeneous and anisotropic Bianchi type Ⅰ space-time have been obtained. The solutions of the Einstein's field equations are obtained by considering(i) the power law relation between Hubble parameter H and scale factor R and(ii) scale factor of the form R =-1/t + t^2, t > 1. The assumptions lead to constant and variable deceleration parameter respectively. The physical and dynamical behaviors of the models have been discussed with the help of graphical representations. Also we have discussed the stability and physical acceptability of solutions for solution type-Ⅰ and solution type-Ⅱ.

关键词： Bianchi type Ⅰ space tine cosmological constant gravitational constant generalized Chaplygin gas

Variability in physical properties of plantation-grown progenies of Melia composita and determination of a kiln-drying schedule

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Journal of Forestry Research 2018年第5期29卷 1435-1442页

作者： Shailendra Kumar Bhushan U.kelkar Ajit K.Mishra Susanta K.Jena Forest Products Division Forest Research Institute

Plantation-grown progenies of Melia composita *** studied for variability in several physical properties： density,radial and tangential shrinkage,longitudinal permeability of heartwood and ***,flat-sawn planks from each of the progeny were subjected to a quick-drying test for determination of kilndrying *** mean density of the species was 0.39 g cm^（-3） and the wood may be categorized as light *** radial shrinkage（%） for the species was 2.8% with progeny-wise variation in radial shrinkage from 1.56 to 4.11%.Mean tangential shrinkage（%） for the species was 5.54% with progeny-wise variation in tangential shrinkage from 3.69 to 7.71%.The resultant tangentialradial shrinkage ratio was 1.98（less than two）,which suggests that the wood is relatively stable with respect to drying *** sapwood and heartwood longitudinal permeability of the species were 3.38 and 2.02 Darcy,*** longitudinal permeability of sapwood and heartwood indicate better drying and preservative properties of the *** quick-drying test method suggests that the species is less susceptible to drying *** the test,only moderate checks and cracks were observed.A tentative kiln-drying schedule was recommended based on these results.

关键词： Melia composita Willd. Density Radial and tangential shrinkage Longitudinal permeability Quickdrying test Kiln-drying schedule

An Unusually Large Foreign Body in Oesophagus in a 2-Year-Old Male Child

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International Journal of Otolaryngology and Head & Neck Surgery 2015年第3期4卷 259-264页

作者： Ajinkya.kelkar Kalpesh Patil Department of Otolaryngology and Head and Neck Surgery Yashwantrao Chavan Hospital Pune Maharashtra India Department of Paediatric Surgery Yashwantrao Chavan Hospital Pune Maharashtra India

A large variety of foreign bodies are swallowed by children, but the majority of those pass through the gastrointestinal tract without any adverse effects. The highest incidence of swallowed foreign bodies occurs in children between 6 months and 3 years. We reported to you an unusually large foreign body ingested by a 2-year-old male patient who underwent a rigid oesophagoscopy but the foreign body had to be removed by open surgical technique. It is advisable to have a multidisciplinary approach while dealing with such cases.

关键词： Foreign Body Screw Oesophagoscopy Gastrostomy

核黄素角膜胶原交联治疗早期轻中度圆锥角膜的研究（英文）

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国际眼科杂志 2017年第2期17卷 200-204页

作者： Jai Aditya.kelkar Aditya Shreekant kelkar Ekta Rakesh Arora Shreekant Bhaskar kelkar Mehmood G Sayad Shivaji Nagar Near Phule博物馆国家眼科研究所印度马哈拉施特拉邦浦那411005

目的:核黄素角膜胶原交联早期治疗轻度至中度圆锥角膜的预后。方法:三级眼科诊疗中心的前瞻性研究。共38例47眼轻至中度圆锥角膜接受核黄素角膜胶原交联治疗的患者纳入本研究。术前数据包括参与眼数,视力,眼压,角膜厚度与角膜地形图。... 详细信息

目的:核黄素角膜胶原交联早期治疗轻度至中度圆锥角膜的预后。方法:三级眼科诊疗中心的前瞻性研究。共38例47眼轻至中度圆锥角膜接受核黄素角膜胶原交联治疗的患者纳入本研究。术前数据包括参与眼数,视力,眼压,角膜厚度与角膜地形图。术后数据包括最佳矫正视力,眼压,角膜厚度,角膜地形图和术后并发症。结果:研究包含年龄16~30岁的患者38例47眼。平均术前视力为0.58±0.40 logM AR,术后随访2a显著提高(0.40±0.27logM AR)(P=0.005)。平均术前角膜曲率为50.5±4.6 D,术后显著降低。随访2a平均角膜曲率为48.2±4.1 D(P=0.011)。术后随访2a眼压(15.1±3.0mmH g)较术前(12.9±2.5 mmH g)显著增加(P=0.035)。术前角膜厚度467.9±38.8μm,术后随访2a(465.0±39.3μm)明显降低。所有患者均无并发症出现。结论:早期使用核黄素角膜胶原交联治疗轻至中度圆锥角膜可获得长期的良好视力,而不必等其发展为进展期。

关键词：角膜圆锥角膜角膜胶原交联

Bulk Viscous Anisotropic Cosmological Models with Generalized Chaplygin Gas with Time Varying Gravitational and Cosmological Constants

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Natural Science 2015年第6期7卷 312-323页

作者： Shubha Kotambkar Gyan Prakash Singh Rupali kelkar Department of Applied Mathematics Laxminarayan Institute of Technology Rashtrasant Tukadoji Maharaj Nagpur University Nagpur India Department of Mathematics Visvesvaraya National Institute of Technology Nagpur India Department of Applied Mathematics S. B. Jain Institute of Technology Management and Research Nagpur India

This paper is devoted to studying the generalized Chaplygin gas models in Bianchi type III space- time geometry with time varying bulk viscosity, cosmological and gravitational constants. We are considering the condition on metric potential . Also to obtain deterministic models we have considered physically reasonable relations like , and the equation of state for generalized Chaplygin gas given by . A new set of exact solutions of Einstein’s field equations has been obtained in Eckart theory, truncated theory and full causal theory. Physical behaviour of the models has been discussed.

关键词： Bianchi Type III Bulk Viscosity Cosmological Constant Gravitational Constant Generalized Chaplygin Gas

Back to basics:A meta-analysis of stump management during open appendicectomy for uncomplicated acute appendicitis

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World Journal of Surgical Procedures 2013年第3期3卷 47-53页

作者： Gianpiero Gravante Shuker Yahia Roberto Sorge George Mathew Ashish kelkar Department of Colorectal Surgery Kettering General Hospital NN16 8UZ KetteringUnited Kingdom Department of Colorectal Surgery George Eliot HospitalCV10 7DJ NuneatonUnited Kingdom Department of Human Physiology Laboratory of Biometry University of Rome "Tor Vergata" 00173 RomeItaly

AIM: To compare simple ligation vs stump invagination during open appendicectomy for uncomplicated acute appendicitis on the risk of postoperative complications. METHODS: A meta-analysis was conducted on randomised controlled trials comparing the two stump closure methods in open appendicectomy. Databases searched were Pub Med, EMBASE and Cochrane Library databases. Included were those studies focusing on inflamed and suppurative appendicitis while perforated and gangrenous appendix was excluded. We also excluded retrospective case-control studies, commentaries, historical technical articles, or trials involving laparoscopic appendicectomies. The outcome of the meta-analysis was to find eventual differences in theincidence of postoperative ileus and wound infections between the two techniques of stump invagination. RESULTS: Seven studies were included corresponding to 1468 patients. Postoperative complications consisted in wound infections(7%), ileus(4%), pyrexia(2%), vomiting(1%), obstructions from adhesions(0.1%). No cases of peritonitis, fecal fistulas(stump leaks), abdominal abscesses or wound dehiscences were reported. Postoperative ileus within the first 72 h was four times more frequent with stump invagination compared to simple ligation(OR: 4.06; 95%CI: 2.14-7.70; P < 0.0001). No significant differences were noted for wound infections(OR: 1.24; 95%CI: 0.83-1.87; P = 0.30) while for the remaining complications the incidence was extremely low in both groups. There was a high homogeneity on results(Q value for heterogeneity of postoperative ileus P = 0.17; Q value for heterogeneity of wound infections P = 0.98). CONCLUSION: Stump invagination does not seem to prevent infective complications but is associated with an increased risk of postoperative ileus in uncomplicated cases. Appropriate studies on complicated appendicitis should now evaluate the influence of the two techniques in this higher-risk subgroup.

关键词： Appendiceal stump Open appendicectomy Invagination Appendicitis Complications

Intraperitoneal drains during open appendicectomy for gangrenous and perforated appendicitis

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World Journal of Surgical Procedures 2013年第3期3卷 18-24页

作者： Gianpiero Gravante John Overton Mohamed Elshaer Roberto Sorge Ashish kelkar Department of Colorectal Surgery Kettering General HospitalKetteringNorthamptonshireNN16 8UZUnited Kingdom Department of Colorectal Surgery Royal Oldham HospitalOldhamOL1 2JHUnited Kingdom Department of Human Physiology Laboratory of BiometryUniversity of Tor Vergata00133 RomeItaly

Intra-abdominal drains are still routinely used in the surgical management of gangrenous and perforated appendicitis. A systematic review was performed with the aim of establishing their influence on postoperative complications in such cases. A literature search was conducted using the search engines Pub Med and Cochrance Central Register of Controlled Trials. Included were retrospective case-controlled and prospective randomized controlled trials on the use of drain for open appendicectomy in gangrenous and perforated appendicitis. Twelve articles were found that met the inclusion criteria. Intrabdominal abscesses, postoperative ileus, surgical site infections, fecal fistulas and burst abdomen had significant higher incidences in the drain vs non drain group(10.3%, 20.3%, 32.5%, 3.4% and 5.7% vs 4.7%, 8.5%, 16.2%, 0% and 0%, respectively). In most cases the risk was more than doubled in the drain group compared to the non-drain one. There were no significant differences among groups in termsof mortality while the results were underpowered to effectively evaluate wound dehiscence and adhesions. The use of intra-abdominal drains in the management of gangrenous and perforated appendicitis by open appendicectomy is associated with an increased rate of common postoperative complications.

关键词： Appendix Appendicectomy Complications Infections Drains

Bulk Viscous Anisotropic Cosmological Models with Dynamical Cosmological 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 gravitational and cosmological constants. Some exact solutions of Einstein’s gravitational field equations with bulk viscosity, gravitational and cosmological constants have been obtained. Several well known forms of cosmological terms have been considered to discuss the effect of cosmological variables. The new cosmological 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 Gravitational and Cosmological “Constant”