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Species diversity, regeneration and dominance as influenced by canopy gaps and their characteristics in tropical evergreen forests of Western Ghats, India

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Journal of Forestry Research 2016年第4期27卷 799-810页

作者： Guddappa Mahalingappa Devagiri Anil Kumar Khaple siddagangaiah mohan Puttanaik Venkateshamurthy Sanjay Tomar Arkalgud Nagaraja Arunkumar Geeta Joshi Department of Natural Resource Management College of Forestry University of Agricultural and Horticultural Sciences Department of Horticulture College of AgricultureUniversity of Agricultural Sciences ICRAF-South Asia NASC Pusa Campus Division of Tree Improvement Institute of Wood Science and Technology

Canopy gaps play a significant role in maintaining structure and composition of tropical forests. This study was carried out in tropical evergreen forests of central Western Ghats in India to understand the influence of canopy gap size and the relationship of gap regime attributes to diversity measures and regeneration. The average gap size in the study area was found to be 396 m2 and around half of gaps were 4–8 years old. Gaps created by natural single tree fall were smaller in size but significantly higher in number. Diversity and regeneration of woody species were compared with canopy gaps and intact vegetation. Species richness and diversity was higher in gaps than in intact vegetation. Macaranga peltata, a shade intolerant species dominated gaps while intact vegetation was dominated by shade tolerant Kingiodendron *** size significantly influenced species diversity and regeneration. Gap area and age were significantly and negatively correlated with diversity measures but positively correlated with regeneration. Among all the attributes of gaps, regeneration was significantly positively correlated with light intensity. Gaps maintained species diversity and favored regeneration of woody species. In addition to gap size and age, other gap ecological attributes also affected species diversity and regeneration.

关键词： canopy forests regeneration dominance tropical woody vegetation intact Species dominated

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Transforming Education with Photogrammetry:Creating Realistic 3D Objects for Augmented Reality Applications

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 185-208页

作者： Kaviyaraj Ravichandran Uma mohan Department of Computational Intelligence School of ComputingSRM Institute of Science and TechnologyKattankulathur603203India

Augmented reality(AR)is an emerging dynamic technology that effectively supports education across different *** increased use of mobile devices has an even greater *** the demand for AR applications in education continues to increase,educators actively seek innovative and immersive methods to engage students in ***,exploring these possibilities also entails identifying and overcoming existing barriers to optimal educational ***,this surge in demand has prompted the identification of specific barriers,one of which is three-dimensional(3D)*** 3D objects for augmented reality education applications can be challenging and time-consuming for the *** address this,we have developed a pipeline that creates realistic 3D objects from the two-dimensional(2D)*** for augmented and virtual reality can then utilize these created 3D *** evaluated the proposed pipeline based on the usability of the 3D object and performance ***,with 117 respondents,the co-creation team was surveyed with openended questions to evaluate the precision of the 3D object created by the proposed photogrammetry *** analyzed the survey data using descriptive-analytical methods and found that the proposed pipeline produces 3D models that are positively accurate when compared to real-world objects,with an average mean score above *** study adds new knowledge in creating 3D objects for augmented reality applications by using the photogrammetry technique;finally,it discusses potential problems and future research directions for 3D objects in the education sector.

关键词： Augmented reality education immersive learning 3D object creation photogrammetry and StructureFromMotion

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Graphene derivatives as efficient hole transport materials for lead-free double perovskite（Cs2SnI6） solar cells: a numerical study

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Optoelectronics Letters 2025年第3期21卷 155-159页

作者： Sarita YADAV Saral K.GUPTA Chandra mohan Singh NEGI Department of Physical Science Banasthali Vidyapith

The double perovskite Cs2SnI6has notable optical and electrical characteristics, rendering it a highly prospective candidate for deployment as the absorber layer in perovskite solar cells （PSCs）. We simulated the performance of PSCs using lead-free Cs2SnI6double perovskite absorber layer and graphene derivatives, namely graphene oxide （GO） and reduced graphene oxide （rGO）, as hole transport layers （HTLs）. Our findings show that r GO offers an excellent hole extraction property with minimal interfacial recombination compared to GO.

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Identification of parameter to assess cracking resistance of asphalt mixtures subjected to aging and moisture conditioning

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第2期9卷 293-304页

作者： Bhaskar Pratim Das Anjan Kumar siddagangaiah Department of Civil Engineering Indian Institute of Technology GuwahatiGuiuahati 781039India

This study comprehensively evaluated different parameters based on tensile strength testing to assess the cracking resistance of asphalt mixtures subjected to aging and moisture *** this purpose,two sources of aggregates were selected to produce hot and warm mix asphalt *** mixtures were subjected to short term and long term aging,three levels of moisture conditioning(freeze thaw cycles),and tested at two temperatures(15℃and 25℃).The load-displacement data was used to determine the fracture work density,fracture energy,toughness index,cracking resistance index,cracking tolerance index,and rate dependent cracking *** was noticed that moisture conditioning increased the variability of the different *** cracking tolerance index and rate dependent cracking index parameter had a much higher coefficient of variation(Co V)with a maximum value close to 50%.Indirect tensile strength,fracture energy,and fracture work density appropriately captured the effect of moisture on cracking resistance of *** cracking resistance index,cracking tolerance index,and rate dependent cracking index increased with an increase in the moisture conditioning *** Statistical analysis showed that tensile strength,fracture work density,and fracture energy were significantly influenced by different aging and moisture conditions *** energy showed better association with fatigue life of asphalt mixtures subjected to three freeze-thaw cycles compared to tensile ***,the fatigue life prediction models showed that both indirect tensile strength and fracture energy significantly influence the fatigue life of asphalt mixtures subjected to aging and moisture conditioning.

关键词： Cracking resistance Aging Moisture Warm mix additive Fatigue life

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A comprehensive review of DC fault protection methods in HVDC transmission systems

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Protection and Control of Modern Power Systems 2021年第1期6卷 1-20页

作者： mohan Muniappan Senior Research Specialist Center for Future Energy Systems(CFES)Rensselaer Polytechnic Institute(RPI)TroyNew YorkUSA

High voltage direct current (HVDC) transmission is an economical option for transmitting a large amount of power over long distances. Initially, HVDC was developed using thyristor-based current source converters (CSC). With the development of semiconductor devices, a voltage source converter (VSC)-based HVDC system was introduced, and has been widely applied to integrate large-scale renewables and network interconnection. However, the VSC-based HVDC system is vulnerable to DC faults and its protection becomes ever more important with the fast growth in number of installations. In this paper, detailed characteristics of DC faults in the VSC-HVDC system are presented. The DC fault current has a large peak and steady values within a few milliseconds and thus high-speed fault detection and isolation methods are required in an HVDC grid. Therefore, development of the protection scheme for a multi-terminal VSC-based HVDC system is challenging. Various methods have been developed and this paper presents a comprehensive review of the different techniques for DC fault detection, location and isolation in both CSC and VSC-based HVDC transmission systems in two-terminal and multi-terminal network configurations.

关键词： HVDC VSC Multi-terminal DC grid DC fault Fault detection and location Fault isolation

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A Review on Friction Stir Welding of Steels

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Chinese Journal of Mechanical Engineering 2021年第6期34卷 195-223页

作者： Dhanesh G mohan ChuanSong Wu Institute of Materials Joining Shandong UniversityJinan 250016China

Friction Stir Welding(FSW)is the most promising solid-state metals joining method introduced in this *** to the conventional fusion welding methods,this FSW can produce joints with higher mechanical and metallurgi-cal ***,FSW was adopted for low melting metals like aluminum *** recent years it has made significant progress in friction stir welding of steels since unfavourable phase transformations occurred in welds due to the melting of the parent and filler metals in fusion welding can be *** main advantage of FSW over traditional fusion welding is the reduction in the heat-affected zone(HAZ),and the joints exhibit excellent mechanical and corrosion resistance *** article reviews the progress in the relevant issues such as the FSW tool mate-rials and tool profiles for joining steels,microstructure and mechanical properties of steels joints,special problems in joining dissimilar ***,in-situ heating sources was used to overcome the main limitations in FSW of hard metals and their alloys,i.e.,tool damages and insufficient heat *** in-situ heating sources like laser,induction heat,gas tungsten arc welding assisted FSW for various types of steels are introduced in this *** the basis of the up-to-date status,some problems that need further investigation are put forward.

关键词： Friction stir welding Steels Microstructure Mechanical testing Hybrid welding

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Determining Potential Passive Islanding Detection Indicators for Single-point Single Inverter,Single-point Multi-inverter and Multi-point Multi-inverter Scenarios

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CSEE Journal of Power and Energy Systems 2022年第3期8卷 696-709页

作者： Nitin Kumar Kulkarni mohan Khedkar Department of Electrical Engineering Visvesvaraya National Institute of TechnologyNagpurIndia

Distributed Generation(DG)sources,predominantly renewable energy-based,such as solar photovoltaic and wind energy sources,have significantly penetrated into power system *** high penetration of DG sources may lead to the formation of unintentional islands,which is hazardous to both the equipment and personnel,if *** this paper,46 passive parameters are considered to find out which candidate(s)are promising for detecting sustained unintentional islands and avoid false DG *** 46 parameters are derived from point of common coupling(PCC)voltage,DG output current,frequency,power factor angle,active and reactive *** these parameters are tested on standard IEEE 13 and 34 bus distribution networks,integrated with inverter-interfaced DGs at different locations for different penetration levels in the MATLAB/SIMULINK *** parameters are tested for different islanding events(comprising of various local loads,such as conventional parallel RLC resonant load,R,RC,and RL loads)and for different non-islanding *** parameters are then ranked accordingly by a suitable averaging approach based performance ranking *** this analysis,the best candidates are obtained for detecting inverter DG islands at single-point(or single PCC)locations and multi-point(or multiple PCCs)*** best passive candidates are obtained for different island scenarios from which a set of promising islanding detection indicators are proposed.

关键词： Averaging approach inverter DG point of common coupling(PCC) passive parameters test system

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A low power, eco-friendly multipurpose thermoelectric refrigerator

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Frontiers in Energy 2016年第1期10卷 79-87页

作者： N. Jagan mohan REDDY Deparmaent of ECE Chaitanya Bharathi Institute of Technology Hyderabad 500075 India

There has been an immense endeavor to mitigate global warming in spite of which it has only been worse. This paper presents the design and imple- mentation of a low power and eco-friendly refrigeration system using the thermoelectric effect. The conventional refrigerators make use of complex mechanisms which involves synchronous operation of various units, namely the compressor, condensers, expansion valves, evaporator, refi＇igerant and so on. But a thermoelectric refrigerator exploits the principle of the Peltier effect, thus avoiding the utilization of these complex components. This even helps curb the release of harmful chlorofluorocarbons （CFCs） into the atmosphere which contributes to the increase in global temperature. Moreover, the temperature can be controlled and set to required values with the help of a microcontroller. Hence, this can be used both for domestic and commercial purposes. The unit does not eject any harmful gases. Therefore, the heat expelled from the unit can be tapped for heating utilities, making the use of this device versatile in its application. Thus this proposal aims not only at reducing the air pollutants by not contributing to it but also at reducing the power consumption.

关键词： low power eco-friendly multipurpose TEC- 12706 Peltier effect microcontroUer (P89V51RD2BN) temperature control

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Development of Tunable Silk Fibroin/Xanthan Biopolymeric Scaffold for Skin Tissue Engineering Using L929 Fibroblast Cells

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Journal of Bionic Engineering 2021年第1期18卷 103-117页

作者： Shailendra Singh Shera Rathindra mohan Banik Bioprocess Technology Laboratory Sschool of Biochemical Engineeringndian Institute of Technology(Banaras Hindu University)Varanasi 221005India Department of Biotechnology Faculty of Engineering&TechnologyRAMA Universit Uittar PradeshKanpur 209217India

Skin acts as protective barrier against a number of factors such as dust,opportunistic microbial and viral infections,regulates body temperature and waste *** cell population plays an important role in devclopment of skin architecturc.A scaffold having capability to support and enhance fibroblast growth is a viable option for wound dressing material which can shorten the time for wound to *** this work,Silk Fibroin(SF)and Xanthan(Xa)were blended in three ratios 80 SF:20 Xa(SFX82),60 SF:40 Xa(SFX64),and 50SF:50 Xa(SFX55)to create SF/Xa *** and other physicochemical properties of SF/Xa scaffold are functions of blending ratios and blend with the ratio 80 SF:20 Xa has the highest *** properties of SF/Xa blends are a function of miscibility with SFX82 having superior thermal propertis of all fabricated *** porosity of SF/Xa scaffolds is in the range of 67%to 50%,with pore size of 58.1 um-45.5 um,water uptake capacity of 92%-86%,and surface roughness of 49.95 nm-385 ***82 shows highest growth rate of L929 fibroblast cells indicating its superiority over other scaffolds for providing biological cues for the growth and proliferation of fibroblastic cells in natural ***82 scaffold is found to be most suitable for fibroblastic cells thereby enhancing the tissue regeneration at wound site.

关键词： blends miscibility FTIR imaging Atomic Force Microscopy(AFM) cytocompatibility wound healing

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Numerical Simulation on Oil Spilling of Submarine Pipeline and Its Evolution on Sea Surface

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Computer Modeling in Engineering & Sciences 2020年第9期124卷 885-914页

作者： Yi Wang mohan Lin National Engineering Laboratory for Pipeline Safety MOE Key Laboratory of Petroleum EngineeringBeijing Key Laboratory of Urban Oil and Gas Distribution TechnologyChina University of PetroleumBeijing102249China

Due to the interaction and corrosion of the seawater,submarine pipelines are easy to be broken to spill *** special environment of subsea restricts the technical development of pipeline ***,the study on the oil spilling model of submarine pipeline is very important for predicting the movement and diffusion of spilled oil,so that oil spilling traces and relating strategies can be *** paper aims to establish an oil spilling model of a submarine pipeline,study the movement characteristics of spilled oil in seawater by numerical simulation,and determine the traces,diffusion range,time to sea surface,***,the maximum horizontal migration distance(MHMD)with corresponding time are analyzed under different oil densities,spilling speeds and seawater *** show that the MHMD decreases first and then increases while the time to achieve the MHMD increases along with increasing oil *** MHMD increases while the time to achieve the MHMD decreases,along with increasing spilling *** the MHMD and corresponding time increase along with increasing seawater *** on numerical results,a correlation of spilling distance and spilling time is proposed to give fast and accurate *** the oil reaches sea surface,oil expansion and transport are ***-Lagrange method is used in the *** and non-dynamic factors are *** show that wind velocity and water velocity are dominant in dynamic *** they are large,spilled oil moves very fast with variable directions in complex flow *** factors such as evaporation,emulsion and solution mainly reduce the volume of oil *** almost do not affect the direction and displacement of spilled *** response should be made for large wind and water velocities when the placement of oil boom is *** the correlation and simulation,emergency responses can be guided effectively to reduce the impact of submarine o

关键词： Computational fluid dynamics submarine pipeline oil spilling pollution control environmental protection

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