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On selection and scaling of ground motions for analysis of seismically isolated structures

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Earthquake Engineering and Engineering Vibration 2016年第4期15卷 633-648页

作者： deepak R. Pant Manika Maharjan Department of Civil Engineering University of Toronto Toronto ON M5S 1A4 Canada Atkins Limited The Wells Church Street Epsom KT17 4PE United Kingdom

A broader consensus on the number of ground motions to be used and the method of scaling to be adopted for nonlinear response history analysis （RHA） of structures is yet to be reached. Therefore, in this study, the effects of selection and scaling of ground motions on the response of seismically isolated structures, which are routinely designed using nonlinear RHA, are investigated. For this purpose, isolation systems with a range of properties subjected to bidirectional excitation are considered. Benchmark response of the isolation systems is established using large sets of unscaled ground motions systematically categorized into pulse-like, non-pulse-like, and mixed set of motions. Different subsets of seven to 14 ground motions are selected from these large sets using （a） random selection and （b） selection based on the best match of the shape of the response spectrum of ground motions to the target spectrum. Consequences of weighted scaling （also commonly referred to as amplitude scaling or linear scaling） as well as spectral matching are investigated. The ground motion selection and scaling procedures are evaluated from the viewpoint of their accuracy, efficiency, and consistency in predicting the benchmark response. It is confirmed that seven time histories are sufficient for a reliable prediction of isolation system displacement demands, for all ground motion subsets, selection and scaling procedures, and isolation systems considered. If ground motions are selected based on their best match to the shape of the target response spectrum （which should be preferred over randomly selected motions）, weighted scaling should be used if pulse-like motions are considered, either of weighted scaling or spectral matching can be used if non-pulse-like motions are considered, and an average of responses from weighted-scaled and spectrum-matched ground motions should be used for a mixed set of motions. On the other hand, the importance of randomly selected motions in represen

关键词： bidirectional excitation seismic isolation selection and scaling spectral matching weighted scaling

Static and Dynamic Analyses of Spliced Column

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Sound & Vibration 2021年第3期55卷 253-262页

作者： deepak Kumar Singh Research Scholar Civil Engineering DepartmentMNNIT AllahabadPrayagraj211004India

The analysis of spliced column has been carried out to detect optimum location of providing splices in the *** the present work,static and dynamic(free vibration)analyses of spliced column have been done by randomising the location of splicing.A symmetrical four storey steel framed building has been modelled,analysed and designed for loads(dead,live and earthquake loads)recommended by Indian Codal provisions using *** critical column at each floor level is identified based on axial force(AF),bending moment(BM)and shear force(SF).The total 16 models of spliced columns have been designed and then modelled in a 3D CAD Design tool(SOLIDWORKS)and then imported in the finite element tool(ANSYSWorkbench 14.0)for detailed *** variation of stress,strain and deflection of the spliced column are shown in the form of ***,the modal analysis is performed to determine the natural *** results of static and dynamic analyses are compared for each modelled spliced column to obtain the optimum location for providing splices in the *** dynamic analysis of spliced column is of utmost importance in the region where dynamic loadings like earthquake,cyclones *** more frequent,and mere static analysis does not account for the safety of the *** study will help the engineers to select directly the optimum size and location of the splices in the column of a steel framed building.

关键词： Column splice finite element method natural frequency modal analysis static analysis steel framed building

Ischemic colitis masquerading as colonic tumor:Case report with review of literature

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World Journal of Gastroenterology 2011年第48期17卷 5324-5326页

作者： Parakkal deepak Radha Devi Internal Medicine University of Chicago(North Shore University Health System) 2650 Ridge AvenueEvanston IL 60201 United States Internal Medicine University of Illinois at Chicago (St Francis Hospital) Evanston IL 60201 United States

Ischemic colitis can mimic a carcinoma on computed tomographic (CT) imaging or endoscopic examination. A coexisting colonic carcinoma or another potentially obstructing lesion has also been described in 20% of the cases of ischemic colitis. CT scan can differentiate it from colon cancer in 75% of cases. However, colonoscopy is the preferred method for diagnosing ischemic colitis as it allows for direct visualization with tissue sampling. Varied presentations of ischemic colitis have been described as an ulcerated or submucosal mass or as a narrowed segment of colon with ulcerated mucosa on colonoscopy. Awareness and early recognition of such varied presentations of a common condition is necessary to differentiate from a colonic carcinoma, and to avoid unnecessary surgery and related complications.

关键词： Colon pathology Colitis Ischemic pathology Colonic neoplasms/diagnosis Differential Diagno-sis Biopsy X-Ray computed tomography

Liver-gut axis in the regulation of iron homeostasis

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World Journal of Gastroenterology 2007年第35期13卷 4737-4745页

作者： deepak Darshan Gregory J Anderson Iron Metabolism Laboratory The Queensland Institute of Medical ResearchBrisbaneAustralia

The human body requires about 1-2 mg of iron per day for its normal functioning, and dietary iron is the only source for this essential metal. Since humans do not possess a mechanism for the active excretion of iron, the amount of iron in the body is determined by the amount absorbed across the proximal small intestine and, consequently, intestinal iron absorption is a highly regulated process. In recent years, the liver has emerged as a central regulator of both iron absorption and iron release from other tissues. It achieves this by secreting a peptide hormone called hepcidin that acts on the small intestinal epithelium and other cells to limit iron delivery to the plasma. Hepcidin itself is regulated in response to various systemic stimuli including variations in body iron stores, the rate of erythropoiesis, inflammation and hypoxia, the same stimuli that have been known for many years to modulate iron absorption. This review will summarize recent findings on the role played by the liver and hepcidin in the regulation of body iron absorption.

关键词： Iron Homeostasis Intestinal iron absorption Liver Hepcidin

NMR relaxation and diffusion studies to probe the motional dynamics of risperidone within PLGA microsphere

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Magnetic Resonance Letters 2023年第2期3卷 197-205,I0005页

作者： deepak Kumar Samanwita Pal Department of Chemistry Indian Institute of Technology JodhpurRajasthan342037.India Central Ayurveda Research Institute Kolkata CCRASBidhannagarKolkata700091India

The present study aims to investigate the motional dynamics of risperidone within polylactic co-glycolic acid(PLGA)microsphere by employing solution state'H and 19F nuclear magnetic resonance(NMR)***,a second-generation fluorinated antipsychotic drug used for the treatment of schizophrenia is commercially marketed as PLGA microsphere formulation resulting in prolonged release of the drug in *** the current trend in the pharmaceutical market is to develop drug formulation with long-acting release(LAR)products,complete physicochemical characterization of such formulations are *** the effects of microsphere encapsulation on the motional properties and diffusion behavior of the drugs are not discussed adequately in any of the earlier *** therefore,have employed NMR relaxation and diffusion measurements to decipher the interaction of PLGA cavity water with risperidone.A detailed analysis of NMR relaxation rates confirmed the event of encapsulation and the presence of local motion in the non-fluorinated end of ***,the relaxation data indicated a significant alteration in 19F chemical shift anisotropy(CSA)and CSA/dipole-dipole(DD)cross-correlated relaxation mechanism and decreased effect of solvent relaxation pointing out reduced water concentration within the microsphere cavity.'H and 19F diffusion coefficients of risperidone led to the information about hydrodynamic radius of risperidone in free and encapsulated *** of hydrodynamic radius supported the presence of limited water in PLGA cavity allowing higher translational mobility of risperidone after the encapsulation.

关键词： Polylactic co-glycolic acid(PLGA)microsphere Motional dynamics 1H and 19F NMR Diffusion Hydrodynamic radius Cross-correlated relaxation

Sustainability Assessment and Ranking of Run of the River(RoR) Hydropower Projects Using Analytical Hierarchy Process(AHP):A Study from Western Himalayan Region of India

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Journal of Mountain Science 2015年第5期12卷 1315-1333页

作者： deepak KUMAR Surjit Singh KATOCH Centre for Energy and Environmental Engineering National Institute of Technology

In the present scenario,tapping the unutilised hydropower potential is one of the highest priorities in developing countries of the *** emphasis is being imparted to run of the river(RoR)mode of power ***,the governments are now facing the dilemma whether to promote small hydropower projects(SHPs) or encourage large hydropower projects(LHPs).RoR large hydropower projects result into large scale cutting of mountains for constructing tunnels and access roads,generation of huge quantity of muck and large scale impact on flora and fauna due to diversion of rivers/*** the other hand,though SHPs are claimed to be greener and more sustainable by a section of researchers and energy planners but,they will be required to be set up in large number to generate equivalent amount of *** aim of this study is to rank the most sustainable installed capacity range of RoR hydropower *** achieve this aim,the study proposes the use of quite popular multi-criteria decision making(MCDM)method of Operation Research named Analytical Hierarchy Process.A case study has been presented from Himachal Pradesh,a hydro rich state located in the western Himalayan *** per sustainability assessment carried out in this study,hydropower projects in the capacity range 1 to 5 MW have been ranked to be the most sustainable.

关键词： Sustainability Run of the river Hydropower project Analytical Hierarchy Process Himalaya

Exploration and insights into the cellular internalization and intracellular fate of amphiphilic polymeric nanocarriers

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Acta Pharmaceutica Sinica B 2021年第4期11卷 903-924页

作者： Samrat Mazumdar deepak Chitkara Anupama Mittal Department of Pharmacy Birla Institute of Technology and Science(BITS-PILANI)Rajasthan 333031India

The benefcial or deleterious effects of nanomedicines emerge from their complex interactions with intracellular pathways and their subcellular ***,the dynamic nature of plasma membrane accounts for the movement of these nanocarriers within the cell towards different organelles thereby not only infuencing their pharmacokinetic and pharmacodynamic properties but also bioavailability,therapeutic effcacy and ***,an in-depth understanding of underlying parameters controlling nanocarrier endocytosis and intracellular fate is *** order to direct nanoparticles towards specifc sub-cellular organelles the physicochemical attributes of nanocarriers can be *** include particle size,shape and surface charge/*** the particle size of nanocarriers below 200 nm contributes to internalization via clathrin and caveolae mediated ***,a moderate negative surface potential confers endolysosomal escape and targeting towards mitochondria,endoplasmic reticulum(ER)and *** review aims to provide an insight into these physicochemical attributes of nanocarriers fabricated using amphiphilic graft copolymers affecting cellular *** principles understood from experimental studies have been extrapolated to draw a general conclusion for the designing of optimized nanoparticulate drug delivery systems and enhanced intracellular uptake via specifc endocytic pathway.

关键词： Amphiphilic Copolymer Nanoparticles Internalization Intracellular fate

Publish/subscribe based information dissemination over VANET utilizing DHT

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Frontiers of Computer Science 2012年第6期6卷 713-724页

作者： Tulika PANDEY deepak GARG Manoj Madhav GORE Department of Computer Science and IT Sam Higginbotom Institute of AgricultureTechnology and SciencesAllahabad 211007India Department of Computer Science and Engineering Thapar UniversityPatiala 147004India Department of Computer Science and Engineering Motilal Nehru National Institute of TechnologyAllahabad 211004India

A vehicular ad-hoc network （VANET） can be visualized as a network of moving vehicles communicating in an asynchronous and autonomous fashion. Efficient and scalable information dissemination in VANET applications is a major challenge due to the movement of vehicles which causes unpredictable changes in network topology. The publish/subscribe communication paradigm provides decoupling in time, space, and synchronization between communicating entities, and presents itself as an elegant solution for information dissemination for VANET like environments. In this paper, we propose our approach for information dissemination which utilizes publish/subscribe and distributed hash table （DHT） based overlay networks. In our approach, we assume a hybrid VANET consisting of stationary info-stations and moving vehicles. These info-stations are installed at every major intersection of the city and vehicles can take the role of publisher, subscriber, or broker depending upon the context. The info-stations form a DHT based broker overlay among themselves and act as rendezvous points for related publications and subscriptions. Further, info-stations also assist in locating vehicles that have subscribed to information items. We consider different possible deployments of this hybrid VANET with respect to the number of info-stations and their physical connectivity with each other. We perform simulations to assess the performance of our approach in these different deployment scenarios and discuss their applicability in urban and semi-urban areas.

关键词： vehicular ad-hoc network (VANET) peer-to- peer overlay network publish/subscribe communication paradigm distributed hash table (DHT)

Experimental investigation and optimization of weld bead characteristics during submerged arc welding of AISI 1023 steel

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Defence Technology（防务技术） 2019年第1期15卷 72-82页

作者： Ankush Choudhary Manoj Kumar deepak Rajendra Unune Department of Mechanical-Mechatronics Engineering The LNM Institute of Information Technology

Submerged arc welding(SAW), owing to its high deposition rate and high welding quality, is widely used in the fabrication of pressure vessel, marine vessel, pipelines and offshore structures. However, selection of an optimum combination of welding parameters is critical in achieving high weld quality and productivity. In this work, initially, the SAW experiments were performed using fractional factorial design to analyze the effect of direct and indirect input parameters, namely, welding voltage, wire feed rate,welding speed, nozzle to plate distance, flux condition, and plate thickness on weld bead geometrical responses viz. bead width, reinforcement, and penetration. The bead on plate technique was used to deposit weld metal on AISI 1023 steel plates. The effect of SAW input parameters on response variables were analyzed using main and interaction effects. The linear regression was used to develop the mathematical models for the response variable. Then, the multi-objective optimization of input parameters was carried out using desirability approach, genetic algorithm and Jaya algorithm. The Jaya algorithm offered better optimization results as compared to desirability approach, genetic algorithm.

关键词： Submerged arc welding Optimization Regression Genetic algorithm Jaya algorithm