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碳基材料的Z型和S型异质结光催化清洁能源综述 被引量:1
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作者 Sahil Rana amit kumar +3 位作者 WANG Tong-tong Gaurav Sharma Pooja Dhiman Alberto García-Penas 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第3期458-482,共25页
碳纳米管/纳米纤维、石墨烯、氧化石墨烯、还原氧化石墨烯、石墨炔、碳量子点和富勒烯等炭材料因具有高导电性、优异的稳定性和生物相容性等独特性能,近年来受到广泛关注。在炭材料中构建Z型和S型异质结已成为在能量转换应用中提高光催... 碳纳米管/纳米纤维、石墨烯、氧化石墨烯、还原氧化石墨烯、石墨炔、碳量子点和富勒烯等炭材料因具有高导电性、优异的稳定性和生物相容性等独特性能,近年来受到广泛关注。在炭材料中构建Z型和S型异质结已成为在能量转换应用中提高光催化效率的一种有效策略。本文综述了光催化制氢和CO_(2)还原等清洁能源的基本原理,阐述了它们各自的机理和优势。此外,还讨论了不同类型的炭材料以及其中Z型和S型异质结的合成和构建,强调了它们在促进电荷分离、减少光生载流子复合损失和扩大光谱响应范围方面的作用。以太阳能燃料生产为重点,讨论和总结了碳基Z型和S型异质结在光催化制氢和还原CO_(2)方面的最新进展。最后,讨论了目前碳基光催化剂领域的瓶颈和挑战,并对该领域的未来发展提出了有价值的见解。 展开更多
关键词 炭材料 异质结 Z型 S型 光催化 氢能材料
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Deep Q-Learning Driven Protocol for Enhanced Border Surveillance with Extended Wireless Sensor Network Lifespan
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作者 Nimisha Rajput amit kumar +3 位作者 Raghavendra Pal Nishu Gupta Mikko Uitto Jukka Mäkelä 《Computer Modeling in Engineering & Sciences》 2025年第6期3839-3859,共21页
Wireless Sensor Networks(WSNs)play a critical role in automated border surveillance systems,where continuous monitoring is essential.However,limited energy resources in sensor nodes lead to frequent network failures a... Wireless Sensor Networks(WSNs)play a critical role in automated border surveillance systems,where continuous monitoring is essential.However,limited energy resources in sensor nodes lead to frequent network failures and reduced coverage over time.To address this issue,this paper presents an innovative energy-efficient protocol based on deep Q-learning(DQN),specifically developed to prolong the operational lifespan of WSNs used in border surveillance.By harnessing the adaptive power of DQN,the proposed protocol dynamically adjusts node activity and communication patterns.This approach ensures optimal energy usage while maintaining high coverage,connectivity,and data accuracy.The proposed system is modeled with 100 sensor nodes deployed over a 1000 m×1000 m area,featuring a strategically positioned sink node.Our method outperforms traditional approaches,achieving significant enhancements in network lifetime and energy utilization.Through extensive simulations,it is observed that the network lifetime increases by 9.75%,throughput increases by 8.85%and average delay decreases by 9.45%in comparison to the similar recent protocols.It demonstrates the robustness and efficiency of our protocol in real-world scenarios,highlighting its potential to revolutionize border surveillance operations. 展开更多
关键词 Wireless sensor networks(WSNs) energy efficiency reinforcement learning network lifetime dynamic node management autonomous surveillance
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Effectiveness,safety,and feasibility of outpatient parenteral antimicrobial therapy in a resource-limited setting:A pilot longitudinal study
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作者 amit kumar Prasan kumar Panda 《World Journal of Methodology》 2025年第4期268-276,共9页
BACKGROUND Outpatient parenteral antimicrobial therapy(OPAT)offers a crucial method for administering intravenous/intramuscular antimicrobials outside of hospital settings,allowing patients to complete treatment safel... BACKGROUND Outpatient parenteral antimicrobial therapy(OPAT)offers a crucial method for administering intravenous/intramuscular antimicrobials outside of hospital settings,allowing patients to complete treatment safely while avoiding many hospital-acquired complications.This is a major boost or low-hanging fruit intervention in antimicrobial stewardship practices with multiple targets like decreasing hospital stays,its related complications,the economy,the burden on hospitals,etc.However,resource-constrained countries like India practices rarely OPAT in an evidence-based way.AIM To evaluate the effectiveness,safety,and feasibility along with barriers and facilitators of OPAT practices in resource-poor settings,with a focus on its role in antimicrobial stewardship.METHODS This pilot longitudinal observational study included patients who met OPAT checklist criteria and were committed to post-discharge follow-up.Pre-discharge education and counselling were provided,and demographic data were recorded.Various outcome measures,including barriers and facilitators,were identified through an extensive literature review,fishbone diagram preparation,data collection and analysis,and patient feedback.All healthcare workers who were taking care of the patients discharged with OPAT were contacted with openended questions to get data on feasibility.The study was approved by the Institutional Ethics Committee of All India Institute of Medical Sciences,Rishikesh.We used descriptive analysis and theχ2 test to analyze data.P value<0.05 was considered significant.RESULTS Out of 20 patients,the mean age was 37 years.The cohort comprised 13 males.OPAT was administered at home in 15 cases and at nursing homes in 5 cases,with nine patients receiving treatment from family members and 11 patients receiving care from a local nurse.The infections requiring OPAT included:Kidney-urinary tract(6 cases),gastrointestinal tract(4 cases),respiratory tract(4 cases),meningitis(3 cases),endocarditis(2 cases),and multiple visceral abscesses(1 case).Nineteen out of 20 patients achieved afebrile status.Half of the patients did not receive education,counselling,or demonstrations prior to discharge,but all patients rated the service as good/excellent.According to doctors’feedback,OPAT is highly beneficial and effective for patients when systematically implemented with daily telephonic monitoring,but faces challenges due to the lack of standardized protocols,dedicated teams,and adequate resources.The implementation of OPAT resulted in a reduction of hospitalization duration by an average of two weeks.CONCLUSION This pilot study proves that OPAT is safe,feasible,and efficacious by reducing two weeks of hospitalization in resource-poor settings.OPAT contributes directly to antimicrobial stewardship by reducing hospital stays and hospital-acquired complications,which is vital in combating antimicrobial resistance(AMR)and aligns with the global action plan for AMR in infection prevention and optimal antimicrobial utilization. 展开更多
关键词 Antimicrobial resistance Barriers and facilitators Integrated antimicrobial stewardship Outpatient parenteral antimicrobial therapy Telephonic monitoring
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Efficient Application to Remove Arsenic and Antimony from theWater Environment Using Renewable Carbon-Based Materials:A Review
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作者 Tongtong Wang Zhenhui Pan +5 位作者 Di Zhang Hui Shi Murat Yilmaz amit kumar Gaurav Sharma Tao Liu 《Journal of Renewable Materials》 2025年第6期1103-1137,共35页
With the rapid development of industry,the environmental problems caused by heavy metal arsenic and antimony are becoming increasingly serious.Therefore,it is urgent to solve the problem of arsenic and antimony pollut... With the rapid development of industry,the environmental problems caused by heavy metal arsenic and antimony are becoming increasingly serious.Therefore,it is urgent to solve the problem of arsenic and antimony pollution in the water environment.Renewable carbon-based materials,as a kind of adsorbent widely used in wastewater treatment,have been the focus of scholars’research for many years.In this review,the preparation methods,characteristics,and applications of renewable carbon-based materials(biochar,activated carbon,carbon nanotubes,and graphene)for the removal of arsenic and antimony are described in detail.Based on adsorption kinetics,isothermal adsorption,temperature,pH,and coexisting ions,we discuss the process of adsorption of arsenic and antimony by renewable carbon-based materials,explore the mechanism of adsorption of anions in water by renewable carbon-basedmaterials,and comparatively analyze the differences in adsorption performance of arsenic and antimony by different renewable carbon-based materials.Compared with biochar,activated carbon,carbon nanotube,and graphene renewable materials loaded with iron-manganese oxides have better removal effects on arsenic and antimony wastewater.Extensive research data shows that biochar,as a renewable material,is recommended,followed by activated carbon.Both are recommended because of their excellent adsorption properties and low production costs.Finally,the prospects and challenges of the application of renewable carbon-based materials in wastewater treatment are discussed,and the directions and development trends of future research are pointed out,which provide references and insights for further promoting the application of renewable carbon-based materials in wastewater treatment. 展开更多
关键词 Renewable carbon-based materials ARSENIC ANTIMONY adsorption mechanisms wastewater treatment
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Recent advances in rare earth metal ferrites-based heterojunctions for photocatalytic water treatment,hydrogen production and CO_(2)conversion
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作者 Sahil Rana amit kumar +2 位作者 Pooja Dhiman Gaurav Sharma Tongtong Wang 《Journal of Rare Earths》 2025年第8期1571-1589,I0001,共20页
Rare earth metal ferrites-based heterojunctions have garnered significant attention in recent years due to their exceptional photocatalytic properties and potential applications in water treatment and energy conversio... Rare earth metal ferrites-based heterojunctions have garnered significant attention in recent years due to their exceptional photocatalytic properties and potential applications in water treatment and energy conversion.The incorporation of rare earth metal ferrites into heterojunction photocatalytic systems enhances light absorption,charge separation and photocatalytic efficiency.This review comprehensively discusses some common types of rare earth metal ferrites such as LaFeO_(3),GdFeO_(3),SmFeO_(3),PrFeO_(3)and CeFeO_(3)and their properties as photocatalysts.The photocatalytic pollutants removal and energy conversion mechanisms are discussed in detail and various types of heterojunctions reported in literature based on rare earth metal ferrites and their synthetic routes are also explored.The recent key findings and advances in the heterojunctions based on these rare earth metal ferrites for the pollutants removal and energy conversion applications are summarized.Despite notable progress in enhancing photocatalytic efficiency and stability,several challenges remain.Current research highlights improvements in material synthesis and performance,but issues such as high production costs,scalable synthesis and limited long-term stability persist.Future directions should focus on exploring uncharted applications,novel material combinations and enhancing the practical implementation of these heterojunctions to fully exploit their potential in environmental and energy technologies. 展开更多
关键词 Rare earth metal ferrites HETEROJUNCTIONS PHOTOCATALYTIC Pollutants removal Energy conversion
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A Soft Glove with Proprioceptive Sensing and Multi-modal Haptic Feedback for VR and Telerobotic Applications
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作者 Debadrata Sarkar amit kumar Aman Arora 《Journal of Bionic Engineering》 2025年第2期684-702,共19页
This research paper introduces a soft VR glove that enhances how users interact with virtual objects. It seamlessly integrates discrete modules for sensing and providing haptic feedback, encompassing tactile and kinae... This research paper introduces a soft VR glove that enhances how users interact with virtual objects. It seamlessly integrates discrete modules for sensing and providing haptic feedback, encompassing tactile and kinaesthetic aspects while prioritizing wearability and natural finger movements. The glove employs custom-designed flexible bend sensors with carbon-impregnated film for in-situ joint angle tracking, simplifying the sensing system and enhancing portability. A multi-modal haptic feedback approach includes an innovative pneumatically actuated tactile feedback technique and a motor-tendon-driven kinaesthetic feedback system, providing exceptional realism in virtual object manipulation. The glove’s kinaesthetic feedback lets users perceive virtual objects’ size, shape, and stiffness characteristics. Psychophysical investigations demonstrate how readily the users acclimate to this hardware and prove each module’s effectiveness and synergistic operation. This soft VR glove represents a minimalist, lightweight, and comprehensive solution for authentic haptic interaction in virtual environments, opening new possibilities for applications in various fields. 展开更多
关键词 Virtual reality and interfaces Tactile feedback Haptics and haptic interfaces Soft sensors and actuators
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石墨炔:一种用于合成水污染物有效吸附剂的新型炭材料
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作者 Gaurav Sharma Yaksha Verma +3 位作者 amit kumar Pooja Dhiman WANG Tong-tong Florian JStadler 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第2期173-200,共28页
石墨炔(GDY)是一种新生的二维材料,其在去除水溶液中污染物的研究方面引起了广泛关注。GDY是sp和sp2杂化碳原子的框架,其在二维对称网络中存在苯环和二乙基键,因此具有优异的共轭性、独特的可调谐电子性能、以及优异的化学和热稳定性。... 石墨炔(GDY)是一种新生的二维材料,其在去除水溶液中污染物的研究方面引起了广泛关注。GDY是sp和sp2杂化碳原子的框架,其在二维对称网络中存在苯环和二乙基键,因此具有优异的共轭性、独特的可调谐电子性能、以及优异的化学和热稳定性。GDY的分子中有C≡C键,且具有均匀分布的三角形孔,可提供更多的反应位点和多种反应路径。因而,GDY具有吸附性,其作为吸附剂时在去除污染水中的油、有机污染物、染料和金属方面表现优异。在已发表的文献中,GDY被用作吸附剂的报道十分有限。本文综述了GDY的合成方法、GDY作为吸附剂的应用以及GDY基吸附剂的表征,并展望了GDY在污染物修复中的应用前景。 展开更多
关键词 石墨炔 合成 吸附 污染物 合理机制
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Longitudinally extensive transverse myelitis associated with scrub typhus:A case report
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作者 amit kumar Rajesh Chetiwal Shweta Tanwar 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第8期375-378,共4页
Rationale:Longitudinally extensive transverse myelitis(LETM)is a rare inflammatory demyelinating disease predominantly associated with autoimmune and inflammatory disorders.Scrub typhus can cause a variety of neurolog... Rationale:Longitudinally extensive transverse myelitis(LETM)is a rare inflammatory demyelinating disease predominantly associated with autoimmune and inflammatory disorders.Scrub typhus can cause a variety of neurological complications,which may result in poor recovery and long-term disability.This report reveals a rare linkage between LETM and scrub typhus.Patient concerns:A 24-year-old female presented with a history of fever for 10 days associated with progressive quadriparesis.Physical examination revealed bilateral lower limb weakness(grade 0/5)and bilateral upper limb weakness(grade 2/5)with reduced sensation below the T3 dermatome.Diagnosis:Scrub typhus presenting with longitudinally extensive transverse myelitis.Interventions:Steroid pulse therapy with antibiotics supported by early intensive rehabilitation.Outcomes:Complete recovery was achieved.Lessons:This case report highlights the importance of considering scrub typhus as a potential cause of LETM in endemic regions,particularly in patients presenting with febrile illness and neurological symptoms. 展开更多
关键词 Longitudinally extensive transverse myelitis Scrub typhus Orientia tsutsugamushi Case report
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Clinical outcomes of triceps reflecting anconeus pedicle and olecranon osteotomy approach for distal humerus intercondylar fractures
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作者 Rohit Ailani Sanjeev kumar Bhuyan +2 位作者 Brejesh kumar Prasad amit kumar Namrata Dawani 《World Journal of Orthopedics》 2024年第6期570-577,共8页
BACKGROUND The preferred treatment for distal humeral intercondylar fractures is open reduction and internal fixation.While there is consensus about the posterior approach,several posterior approaches have been develo... BACKGROUND The preferred treatment for distal humeral intercondylar fractures is open reduction and internal fixation.While there is consensus about the posterior approach,several posterior approaches have been developed.It is debatable as to which approach is best.AIM To compare triceps reflecting anconeus pedicle(TRAP)and olecranon osteotomy approaches for internal fixation of distal humeral intercondylar fracture.METHODS In total,40 cases of Arbeitsgemeinschaft für Osteosynthesefragen/Association of the Study of Internal Fixation type C,closed,and Gustilo type I intercondylar humeral fractures were included.Patients ranged in age from 18 years to 70 years.The patients were randomized into two groups:TRAP group and olecranon osteotomy group,with 20 cases in each.All were followed up at 6 wk,3 months,6 months,and 12 months.Functional outcomes were measured in terms of flexion-extension arc,Disabilities of Arm,Shoulder and Hand score,and Mayo Elbow Performance Score.RESULTS The mean age was 43.2 years in the TRAP group and 37.5 years in the olecranon osteotomy group.The mean operative time and mean duration of hospital stay in the TRAP group were significantly higher than in the olecranon osteotomy group(119.5 vs 111.5 min and 9.85 vs 5.45 d,respectively).The mean arc of flexion-extension,Disabilities of Arm,Shoulder and Hand score,and Mayo Elbow Performance Score were comparable without any significant difference in the groups at the 12-month follow-up(107.0 vs 106.2,18.3 vs 15.7,and 84.2 vs 86.2,respectively).Ulnar paresthesia and superficial infections were comparable in both groups(2 cases vs 3 cases and 3 cases vs 2 cases,respectively).Hardware prominence was significantly higher in the olecranon osteotomy group,mostly due to tension band wiring.CONCLUSION Both approaches were equivalent,but there is a need for further study including higher numbers of subjects and longer study duration to prove the benefits of one approach over the other. 展开更多
关键词 Elbow joint Humeral fracture OSTEOTOMY INTERNAL Fracture fixation
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Biotechnological Transformation of Lignocellulosic Biomass in to Industrial Products: An Overview 被引量:1
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作者 amit kumar Archana Gautam Dharm Dutt 《Advances in Bioscience and Biotechnology》 2016年第3期149-168,共20页
Lignocellulose—a major component of biomass available on earth is a renewable and abundantly available with great potential for bioconversion to value-added bio-products. The review aims at physio-chemical features o... Lignocellulose—a major component of biomass available on earth is a renewable and abundantly available with great potential for bioconversion to value-added bio-products. The review aims at physio-chemical features of lignocellulosic biomass and composition of different lignocellulosic materials. This work is an overview about the conversion of lignocellulosic biomass into bio-energy products such as bio-ethanol, 1-butanol, bio-methane, bio-hydrogen, organic acids including citric acid, succinic acid and lactic acid, microbial polysaccharides, single cell protein and xylitol. The biotechnological aspect of bio-transformation of lignocelluloses research and its future prospects are also discussed. 展开更多
关键词 Lignocellulosic Biomass Bio-Transformation BIO-ENERGY Organic Acids Microbial Polysaccharides Single Cell Proteins
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Effects of Ethanol Addition and Biological Pretreatment on Soda Pulping of Eulaliopsis binata 被引量:1
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作者 Archana Gautam amit kumar Dharm Dutt 《Journal of Biomaterials and Nanobiotechnology》 2016年第2期78-90,共13页
Morphological characteristics and proximate chemical analysis of E. binata showed it as a suitable raw material for writing and printing grade paper. Maximum pulp yield (43.58%) of kappa number 17.38 with 0.9% screeni... Morphological characteristics and proximate chemical analysis of E. binata showed it as a suitable raw material for writing and printing grade paper. Maximum pulp yield (43.58%) of kappa number 17.38 with 0.9% screening rejects was obtained at 12% of active alkali (as Na2O) pulping temperature 130&degC, cooking time 120 min and solid to liquor ratio 1:4. During bio-soda pulping of E. binata, pulp yield decreased slightly while pulp brightness, tensile index, burst index and double fold numbers were improved by 4.1%, 24.94%, 14.03% and 48.45% respectively compared to soda pulping. During ethanol-soda pulping of E. binata, pulp yield, pulp brightness, tensile index, burst index and double fold numbers were improved by 3.9%, 6.6%, 32.18%, 35.40% and 77.31% respectively compared to soda pulping. 展开更多
关键词 Ethanol-Soda Pulping BIO-PULPING Eulaliopsis binata Schizophyllum commune Fibre Morphology
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Differentiation of Sheeppox and Goatpox Viruses by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism 被引量:12
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作者 Gnanavel Venkatesan Vinayagamurthy Balamurugan +2 位作者 Revaniah Yogisharadhya amit kumar Veerakyathappa Bhanuprakash 《Virologica Sinica》 CAS CSCD 2012年第6期353-359,共7页
In the present study,the partial gene sequences of P32 protein,an immunogenic envelope protein of Capripoxviruses (CaPV),were analyzed to assess the genetic relationship among sheeppox and goatpox virus isolates,and r... In the present study,the partial gene sequences of P32 protein,an immunogenic envelope protein of Capripoxviruses (CaPV),were analyzed to assess the genetic relationship among sheeppox and goatpox virus isolates,and restriction enzyme specific PCR-RFLP was developed to differentiate CaPV strains.A total of six goatpox virus (GTPV) and nine sheeppox virus (SPPV) isolates of Indian origin were included in the sequence analysis of the attachment gene.The sequence analysis revealed a high degree of sequence identity among all the Indian SPPV and GTPV isolates at both nucleotide and amino acid levels.Phylogenetic analysis showed three distinct clusters of SPPV,GTPV and Lumpy skin disease virus (LSDV) isolates.Further,multiple sequence alignment revealed a unique change at G120A in all GTPV isolates resulting in the formation of Dra I restriction site in lieu of EcoR I,which is present in SPPV isolates studied.This change was unique and exploited to develop restriction enzyme specific PCR-RFLP for detection and differentiation of SPPV and GTPV strains.The optimized PCR-RFLP was validated using a total of fourteen (n=14) cell culture isolates and twenty two (n=22) known clinical samples of CaPV.The Restriction Enzyme specific PCR-RFLP to differentiate both species will allow a rapid differential diagnosis during CaPV outbreaks particularly in mixed flocks of sheep and goats and could be an adjunct/supportive tool for complete gene or virus genome sequencing methods. 展开更多
关键词 Sheeppox Goatpox Differential diagnosis PCR-RFLP
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Experimental Evaluation of Certain Pursuit and Evasion Schemes for Wheeled Mobile Robots 被引量:5
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作者 amit kumar Aparajita Ojha 《International Journal of Automation and computing》 EI CSCD 2019年第4期491-510,共20页
Pursuit-evasion games involving mobile robots provide an excellent platform to analyze the performance of pursuit and evasion strategies. Pursuit-evasion has received considerable attention from researchers in the pas... Pursuit-evasion games involving mobile robots provide an excellent platform to analyze the performance of pursuit and evasion strategies. Pursuit-evasion has received considerable attention from researchers in the past few decades due to its application to a broad spectrum of problems that arise in various domains such as defense research, robotics, computer games, drug delivery, cell biology, etc. Several methods have been introduced in the literature to compute the winning chances of a single pursuer or single evader in a two-player game. Over the past few decades, proportional navigation guidance (PNG) based methods have proved to be quite effective for the purpose of pursuit especially for missile navigation and target tracking. However, a performance comparison of these pursuer-centric strategies against recent evader-centric schemes has not been found in the literature, for wheeled mobile robot applications. With a view to understanding the performance of each of the evasion strategies against various pursuit strategies and vice versa, four different proportional navigation-based pursuit schemes have been evaluated against five evader-centric schemes and vice-versa for non-holonomic wheeled mobile robots. The pursuer′s strategies include three well-known schemes namely, augmented ideal proportional navigation guidance (AIPNG), modified AIPNG, angular acceleration guidance (AAG), and a recently introduced pursuer-centric scheme called anticipated trajectory-based proportional navigation guidance (ATPNG). Evader-centric schemes are classic evasion, random motion, optical-flow based evasion, Apollonius circle based evasion and another recently introduced evasion strategy called anticipated velocity based evasion. The performance of each of the pursuit methods was evaluated against five different evasion methods through hardware implementation. The performance was analyzed in terms of time of interception and the distance traveled by players. The working environment was obstacle-free and the maximum velocity of the pursuer was taken to be greater than that of the evader to conclude the game in finite time. It is concluded that ATPNG performs better than other PNG-based schemes, and the anticipated velocity based evasion scheme performs better than the other evasion schemes. 展开更多
关键词 PURSUIT-EVASION WHEELED mobile robot proportional navigation trajectory planning target INTERCEPTION
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Atrazine biodegradation efficiency, metabolite detection, and trzD gene expression by enrichment bacterial cultures from agricultural soil 被引量:5
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作者 Robinson David Jebakumar SOLOMON amit kumar Velayudhan SATHEEJA SANTHI 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2013年第12期1162-1172,共11页
Atrazine is a selective herbicide used in agricultural fields to control the emergence of broadleaf and grassy weeds. The persistence of this herbicide is influenced by the metabolic action of habituated native microo... Atrazine is a selective herbicide used in agricultural fields to control the emergence of broadleaf and grassy weeds. The persistence of this herbicide is influenced by the metabolic action of habituated native microorganisms. This study provides information on the occurrence of atrazine mineralizing bacterial strains with faster metabolizing ability. The enrichment cultures were tested for the biodegradation of atrazine by high-performance liquid chromatography(HPLC) and mass spectrometry. Nine cultures JS01.Deg01 to JS09.Deg01 were identified as the degrader of atrazine in the enrichment culture. The three isolates JS04.Deg01, JS07.Deg01, and JS08.Deg01 were identified as efficient atrazine metabolizers. Isolates JS04.Deg01 and JS07.Deg01 produced hydroxyatrazine(HA) N-isopropylammelide and cyanuric acid by dealkylation reaction. The isolate JS08.Deg01 generated deethylatrazine(DEA), deisopropylatrazine(DIA), and cyanuric acid by N-dealkylation in the upper degradation pathway and later it incorporated cyanuric acid in their biomass by the lower degradation pathway. The optimum pH for degrading atrazine by JS08.Deg01 was 7.0 and 16S rDNA phylogenetic typing identified it as Enterobacter cloacae strain JS08.Deg01. The highest atrazine mineralization was observed in case of isolate JS08.Deg01, where an ample amount of trzD mRNA was quantified at 72 h of incubation with atrazine. Atrazine bioremediating isolate E. cloacae strain JS08.Deg01 could be the better environmental remediator of agricultural soils and the crop fields contaminated with atrazine could be the source of the efficient biodegrading microbial strains for the environmental cleanup process. 展开更多
关键词 ATRAZINE BIODEGRADATION Enterobacter cloacae Deethylatrazine Cyanuric acid trzD gene
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Reduced Model Based Control of Two Link Flexible Space Robot 被引量:11
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作者 amit kumar Pushparaj Mani Pathak Nagarajan Sukavanam 《Intelligent Control and Automation》 2011年第2期112-120,共9页
Model based control schemes use the inverse dynamics of the robot arm to produce the main torque component necessary for trajectory tracking. For model-based controller one is required to know the model parameters acc... Model based control schemes use the inverse dynamics of the robot arm to produce the main torque component necessary for trajectory tracking. For model-based controller one is required to know the model parameters accurately. This is a very difficult task especially if the manipulator is flexible. So a reduced model based controller has been developed, which requires only the information of space robot base velocity and link parameters. The flexible link is modeled as Euler Bernoulli beam. To simplify the analysis we have considered Jacobian of rigid manipulator. Bond graph modeling is used to model the dynamics of the system and to devise the control strategy. The scheme has been verified using simulation for two links flexible space manipulator. 展开更多
关键词 Flexible Space ROBOTS BOND GRAPH Modeling REDUCED Model Based CONTROLLER Euler-Bernoulli Beam
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A three-dimensional numerical study on the effect of geometric asymmetry on arcjet thruster performance 被引量:2
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作者 Hari Prasad NANDYALA amit kumar Jayachandran THANKAPPAN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第5期131-146,共16页
In an arcjet thruster,the cathode and constrictor degrade with time,and the electrical arc discharge may become unsymmetrical.In this work,a three-dimensional numerical model of a hydrogen plasma arcjet is developed a... In an arcjet thruster,the cathode and constrictor degrade with time,and the electrical arc discharge may become unsymmetrical.In this work,a three-dimensional numerical model of a hydrogen plasma arcjet is developed and validated to study the effect of unsymmetrical electric arc discharge on thruster performance.The unsymmetrical arc discharge is realized by introducing a radial shift of the cathode so that the cathode tip offset is 80μm(25%of the constrictor radius).Simulations are conducted for both axially centered cathode(coaxial)and off-centered cathode(non-coaxial)configurations with identical propellant flow rates and input current.Simulations show asymmetrical arc discharge in the non-coaxial cathode configuration,resulting in azimuthally asymmetric Joule heating,species concentrations,and velocity field.This asymmetry continues as the plasma expands in the divergent section of the nozzle.Temperature,species concentrations,and axial velocity exhibit asymmetric radial distribution at the nozzle exit.The computed Joule heating was found to reduce with cathode shift,and consequently,the thrust and specific impulse of the thruster was decreased by about 6.6%.In the case of the non-coaxial cathode,geometric asymmetry also induces a small side thrust. 展开更多
关键词 ARCJET geometric asymmetry 3D numerical modelling space electric propulsion HYDROGEN
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Estimation of Melt Contribution to Total Streamflow in River Bhagirathi and River DhauliGanga at Loharinag Pala and Tapovan Vishnugad Project Sites 被引量:2
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作者 Manohar Arora D S Rathore +2 位作者 R D Singh Rakesh kumar amit kumar 《Journal of Water Resource and Protection》 2010年第7期636-643,共8页
Many of the major rivers in India originate from the Himalayas. These rivers have significant contribution from snow and ice which makes these rivers perennial. Due to steep slopes, all such streams have potential sit... Many of the major rivers in India originate from the Himalayas. These rivers have significant contribution from snow and ice which makes these rivers perennial. Due to steep slopes, all such streams have potential sites for hydropower generation. There is a requirement of estimation of the contribution from snow and glacier melt, rainfall contribution and sub surface contribution in the total runoff for sustainable supply of water to the hydropower plants. Considering this aspects, in this study a snowmelt runoff simulation model SNOWMOD suitable for Himalayan basins developed earlier has been modified and applied for simulation of flows. Input to the model such as glacier cover, permanent snow cover, seasonal snow cover generated through remote sensing techniques were used in conjunction with daily maximum and minimum temperature, rainfall and discharge. Two hydropower dam sites on major tributaries (Bhagirathi and DhauliGanga) of River Ganga have been selected for determination of different runoff components. However, though the data available was for a very limited period but the results indicate that these tributaries have significant contribution from snow and ice for long term sustainability of flows to these schemes. 展开更多
关键词 HIMALAYAS Snow and Ice SNOWMOD Modeling HYDROPOWER Schemes
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Design of a USIM and ECC based handover authentication scheme for 5G-WLAN heterogeneous networks 被引量:2
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作者 amit kumar Hari Om 《Digital Communications and Networks》 SCIE 2020年第3期341-353,共13页
A variety of wireless communication technologies have been developed to provide services to a large number of users.The future integrated 5G-WLAN wireless networks will support seamless and secure roaming,and various ... A variety of wireless communication technologies have been developed to provide services to a large number of users.The future integrated 5G-WLAN wireless networks will support seamless and secure roaming,and various types of real-time applications and services,which will be the trend of next-generation computing paradigm.In this paper,we discuss the privacy and security problems in 5G-WLAN heterogeneous networks and present a logical 5G-WLAN integrated architecture.We also propose a novel USIM and ECC based design of handover authentication for next-generation 5G-WLAN heterogeneous networks that can provide secure and seamless Internet connectivity.Our scheme has the features of strong security and better performance in terms of computation cost,energy cost,and storage cost as compared with the state-of-the-art schemes. 展开更多
关键词 5G ECC WLAN HANDOVER HETEROGENEOUS
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Plant studies in the first Himalayan Biosphere Reserve: a review 被引量:1
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作者 amit kumar Mansa SRIVASTAV +1 位作者 Bhupendra S.ADHIKARI Gopal S.RAWAT 《Journal of Mountain Science》 SCIE CSCD 2019年第2期351-363,共13页
Nanda Devi Biosphere Reserve(NDBR) was declared as the first Himalayan Biosphere Reserve owing to its unique biological and cultural wealth. Its core zones, Nanda Devi National Park and Valley of Flowers National Park... Nanda Devi Biosphere Reserve(NDBR) was declared as the first Himalayan Biosphere Reserve owing to its unique biological and cultural wealth. Its core zones, Nanda Devi National Park and Valley of Flowers National Park, are a UNESCO World Natural Heritage Site. In spite of lying at a high altitude, interplay of factors such as unique geographical location, climate, topography and wide altitudinal variations have endowed NDBR with a rich and diverse flora. Proportionately high percentage of endemic and near endemic plants makes NDBR a very important protected area from conservation point of view. However, its floristic wealth is facing unprecedented threats in the form of climate change and growing anthropogenic pressure. Hence, a need was felt to assess the directionality, quality and sufficiency of past and ongoing research for the conservation of floral and ethnobotanical wealth of NDBR in the absence of any such previous attempt. Based on an extensive review of more than 150 plant studies on NDBR, this communication provides a detailed account of the current state of knowledge and information gaps on flora, vegetation ecology, rare, endangered, threatened(RET) and endemic plants and ethnobotany. Priority research areas and management measures are discussed for the conservation of its unique floral wealth. Incomplete floral inventorization, lack of biodiversity monitoring, meagre studies on lower plant groups, population status of medicinal plants, habitat assessment of threatened taxa and geo-spatial analysis of alpine vegetation were identified as areas of immediate concern. 展开更多
关键词 ENDEMISM ETHNOBOTANY NANDA Devi Himalaya THREATENED TAXA Valley of Flowers
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Plant studies in Himachal Pradesh,Western Himalaya: a systematic review 被引量:1
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作者 Himanshu BARGALI Manisha MATHELA +3 位作者 Rupali SHARMA Monika SHARMA Dani YAMING amit kumar 《Journal of Mountain Science》 SCIE CSCD 2021年第7期1856-1873,共18页
Owing to a predicted rise in temperature,increase in precipitation and the escalating anthropogenic stresses,the Himalayan ecosystems are the most threatened non-polar regions of the world.In the past,there have been ... Owing to a predicted rise in temperature,increase in precipitation and the escalating anthropogenic stresses,the Himalayan ecosystems are the most threatened non-polar regions of the world.In the past,there have been racing extinctions and range shifts of several life forms in this region,particularly of the plant species.Therefore,consistent qualitative and quantitative records on botanical baseline data on a regular basis are indispensable.The current communication attempts to provide a detailed account on the current state of knowledge and research gaps in floristic studies of Himachal Pradesh,Western Himalaya.Based on an extensive review of more than 140 studies in the form of scientific peer reviewed literature on floristics,medicinal and aromatic plants(MAPs),rare,endangered,threatened and endemic species and ethno-botany,it is revealed that the number of floristic studies in Himachal Pradesh have surged in the past years but studies pertaining to the lower plants remain meagre.Unfortunately,the remote valleys including micro-watersheds lying in the coldarid regions are relatively less studied in terms of available growing stock and population status of MAPs.Depleting traditional ethno-botanical knowledge has been the major concern and,many threatened MAPs need to be accessed globally following IUCN standards.Thus,documentation of the conservation status of key MAPs,setting aside conservation areas around viable populations of threatened species,developing germplasm banks of the priority MAPs and monitoring the impacts of climate change has been suggested. 展开更多
关键词 BIODIVERSITY Ethno-botany FLORA Medicinal plants Threatened plants Western Himalaya
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