检索结果-南通市图书馆

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

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

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Phytosociology of stratification in a lowland tropical rainforest occurring north of the Tropic of Cancer in Meghalaya, India

引用

Plant Diversity 2019年第5期41卷 285-299页

作者： uma.shankar Department of Botany North-Eastern Hill University

Stratification in lowland rainforests of Meghalaya,India,which represent the westernmost limit of the rainforests north of the Tropic of Cancer,was studied in horizontal and vertical planes to elucidate the patterns in stacking of species diversity and community attributes,and to draw comparisons with rainforests of‘Indo-Malaya’ecozone(biogeographical realm).All individuals≥10 cm GBH(girth at breast height)were enumerated in six transects of 10 m width and up to 500 m length covering 2.45 ha *** stratification of whole assemblage of species in vertical plane is referred to as‘storey structure’(=height class distribution),which explains structural *** horizontal plane,it is typically referred to as‘stand structure’(=girth class distribution),which explains structural *** stratification of an individual species in vertical plane is referred to as‘loftiness’and in horizontal plane,it is frequently referred to as‘population structure’.The stand structure was characterized by a negative exponential relationship or a reverse J-shaped curve,which is typical of a well regenerating forest *** storey structure was characterized by the low stature of the rainforest(<30 m),subtle layering in the canopy with dearth of discrete multi-stories,narrower widths of the stories and a thick *** cluster analysis and‘candlestick charts’showed that the dominant species spatially segregated in canopy height to profile three strata,viz.,an understory of juveniles and shrubs below 5 m,a middle-storey of intermediate trees between 5 and 15 m,and an overstory of large trees between 15 and 25 *** trees of a few species may reach up to 30 *** individuals tended to scatter in increasingly wider range of height classes from a lower to the next higher girth class,creating a‘torchlight scatter’pattern,with a tendency to concentrate towards smaller height classes due to stochastic factors,which potentially influence vertical growth proportionate t

关键词： Forest stratification Stand structure Storey structure Loftiness Population structure Northeast India

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

3D and 2D topographic correction to estimated geothermal gradient from the base of gas hydrate stability zone in the Andaman Forearc Basin

Energy Geoscience

引用

Energy Geoscience 2024年第2期5卷 314-320页

作者： uma.shankar Department of Geophysics Institute of ScienceBHUVaranasiIndia

Methane gas hydrate related bottom-simulating reflectors(BSRs)are imaged based on the in-line and cross-line multi-channel seismic(MCS)data from the Andaman Forearc *** depth of the BSR depends on pressure and temperature and pore water *** these assumptions,the BSR depth can be used to estimate the geothermal gradient(GTG)based on the availability of in-situ temperature *** calculation is done assuming a 1D conductive model based on available in-situ temperature measurement at site NGHP-01-17 in the study ***,in the presence of seafloor topography,the conductive temperature field in the subsurface is affected by lateral refraction of heat,which focuses heat in topographic lows and away from topographic *** 1D estimate of GTG in the Andaman Forearc Basin has been validated by drilling results from the NGHP-01 expedition.2D analytic modeling to estimate the effects of topography is performed earlier along selected seismic profiles in the study *** study extended to estimate the effect of topography in 3D using a numerical *** corrected GTG data allow us to determine GTG values free of topographic *** difference between the estimated GTG and values corrected for the 3D topographic effect varies up to~5℃/*** conclude that the topographic correction is relatively small compared to other uncertainties in the 1D model and that apparent GTG determined with the 1D model captures the major features,although the correction is needed prior to interpreting subtle features of the derived GTG maps.

关键词： Gas hydrate BSR Geothermal gradient 3D and 2D topographic modeling Andaman Forearc Basin

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Rainforests north of the Tropic of Cancer: Physiognomy, floristics and diversity in ‘lowland rainforests’ of Meghalaya, India

引用

Plant Diversity 2017年第1期39卷 20-36页

作者： uma.shankar Amit Kumar Tripathi Department of Botany North-Eastern Hill University Shillong 793 022 India

The lowland rainforests of Meghalaya, India represent the westernmost limit of the rainforests north of the Tropic of Cancer. These forests, on the Shillong plateau, are akin to Whitmore's ‘tropical lowland evergreen rainforest' formation and exhibit striking similarities and conspicuous differences with the equatorial rainforests in Asia-Pacific as well as tropical seasonal rainforests in southwestern China near the Tropic of Cancer. We found these common attributes of the rainforests in Meghalaya: familial composition with predominance of Euphorbiaceae, Lauraceae, Meliaceae, Moraceae, Myrsiticaceae,Myrtaceae and Rubiaceae; deciduousness in evergreen physiognomy; dominance of mega-and mesophanerophytic life-forms; abundance of species with low frequency of occurrence(rare and aggregated species); low proportional abundance of the abundant species; and truncated lognormal abundance distribution. The levels of stand density and stand basal area were comparable with seasonal rainforests in southwestern China, but were lower than equatorial rainforests. Tropical Asian species predominated flora, commanding 95% of the abundance. The differences include overall low stature(height) of the forest, inconspicuous stratification in canopy, fewer species and individuals of liana, thicker understory,higher proportion of rare species, absence of locally endemic species and relatively greater dominance of Fagaceae and Theaceae. The richness of species per hectare(S) was considerably lower at higher latitudes in Meghalaya than in equatorial rainforests, but was comparable with seasonal rainforests. Shannon's diversity index(H’=4.40 nats for ≥10 cm gbh and 4.25 nats for ≥30 cm gbh) was lower on higher latitudes in Meghalaya in comparison to species-rich equatorial rainforests, but it was the highest among all lowland rainforests near the Tropic of Cancer.

关键词： Lowland rainforest Forest structure Floristics Phytosociology Species richness Life-form spectrum

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Trusted Cluster-Based Communication for Wireless Sensor Network Using Meta-Heuristic Algorithms

引用

Computer Systems Science & Engineering 2023年第5期45卷 1935-1951页

作者： Pankaj Kumar Sharma uma.shankar Modani Department of Computer Engineeing Mahila Engineering CollegeAjmerIndia Department of E&C Engineering Engineering CollegeAjmerIndia

The mobile transient and sensor network’s routing algorithm detects available multi-hop paths between source and destination ***,some methods are not as reliable or trustworthy as ***,finding a reliable method is an important factor in improving communication *** further enhancement of protected communication,we suggest a trust cluster based secure routing(TCSR)framework for wireless sensor network(WSN)using optimization ***,we introduce an efficient cluster formation using a modified tug of war optimization(MTWO)algorithm,which provides loadbalanced clusters for energy-efficient data ***,we illustrate the optimal head selection using multiple design constraints received signal strength,congestion rate,data loss rate,and throughput of the *** parameters are optimized by a butterfly optimal deep neural network(BO-DNN),which provides first-level security towards the selection of the best head ***,we utilize the lightweight signcryption to encrypt the data between two nodes during data transmission,which provides second-level *** model provides an estimation of the trust level of each route to help a source node to select the most secure *** nodes of the network improve reliability and security by maintaining the reliability *** results showed that the proposed scheme achieved 45.6%of delivery ratio.

关键词： Trust model WSN secure routing cluster formation load-balanced clusters

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy Efficient Load Balancing and Routing Using Multi-Objective Based Algorithm in WSN

引用

Intelligent Automation & Soft Computing 2023年第3期35卷 3227-3239页

作者： Hemant Kumar Vijayvergia uma.shankar Modani Department of Electronics&Communication Engineering Govt.Mahila Engineering CollegeAjmerRajasthanIndia Department of Electronics&Communication Engineering Govt.Engineering CollegeAjmerIndia

In wireless sensor network(WSN),the gateways which are placed far away from the base station(BS)forward the collected data to the BS through the gateways which are nearer to the *** leads to more energy consumption because the gateways nearer to the BS manages heavy trafﬁc ***,to over-come this issue,loads around the gateways are to be balanced by presenting energy efﬁcient clustering ***,to enhance the lifetime of the net-work,optimal routing path is to be established between the source node and *** energy efﬁcient load balancing and routing,multi objective based beetle swarm optimization(BSO)algorithm is presented in this *** this algo-rithm,optimal clustering and routing are performed depend on the objective func-tions routingﬁtness and clusteringﬁ*** approach leads to decrease the power *** results show that the performance of the pro-posed BSO based clustering and routing scheme attains better results than that of the existing algorithms in terms of energy consumption,delivery ratio,through-put and network ***,the proposed scheme increases throughput to 72%and network lifetime to 37%as well as it reduces delay to 37%than the existing optimization algorithms based clustering and routing schemes.

关键词： Wireless sensor network(WSN) load balancing clustering routing beetle swarm optimization(BSO)

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Patterns of species dominance, diversity and dispersion in ‘Khasi hill sal' forest ecosystem in northeast India

引用

Forest Ecosystems 2014年第4期1卷 227-246页

作者： Amit Kumar Tripathi uma.shankar Department of Botany North-Eastern Hill University

Background： The ＇Khasi hill sal＇ forest ecosystem in Meghalaya, India represents the easternmost limit of sal distribution. We tested if tree diversity and compositional heterogeneity of this ecosystem was higher than other sal-dominated forests due to moister environment. Methods： Vegetation was sampled in 11 transects of 10 m width and up to 500 m length covering 5.2 ha area. All stems ≥10 cm girth at breast height were enumerated. Results： We found a pattern of mixed dominance of Shored robusta （sal） and Schima wollichii and co-dominance of Pinus kesiyo and Careya arborea. The Shannon＇s diversity index （H＇） was 3.395 nats. This value is remarkably high and competitive to that of moist sal forests of eastern Himalayan foothills and sal-dominated forests of Tripura. A high value of H＇ was manifested by： a） high species richness （S = 123）, b） good equitability （70.6%）, c）＇fair＇ resource apportionment, and d） abundance of rare species （84% species with less than one per cent of total individuals, 67% species with two or less individuals ha-1 and 59% species with one or less individuals ha-1）. The compositional heterogeneity was ＇fair＇（Whittaker＇sβw = 3.15）. The presence of Fagaceae with six species commanding 4.3% of importance value （IVl） and of a pine （P. kesiya） in sal forest was remarkable. As many as 58 species showed ＇low density （〈 10 individuals ha-1）, uniform dispersion＇, five species achieved ＇higher density （〉 10 individuals ha-l）, uniform dispersion＇ and six of the top 10 species were ＇clumped＇. The forest showed an exponential demographic curve illustrating ＇good＇ regeneration of an expanding community. Vertical stratification was simple with a poor canopy and fair subcanopy, which together with low basal area （15.65 m2 . ha-1 for individuals ≥ 10 cm gbh） indicated logging of mature sal trees in the past. Conclusions： The ＇Khasi hill sal＇ forest ecosystem is richer in alpha and beta diversity than most sal-dominated forests, but past logging has reduce

关键词： Forest structure Phytosociology Floristics Beta diversity Abundance Species dispersion Populationstructure Regeneration Shorea robusto

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Tree species diversity and stand structure along major community types in lowland primary and secondary moist deciduous forests in Tripura,Northeast India

引用

Journal of Forestry Research 2012年第4期23卷 553-568页

作者： Koushik Majumdar uma.shankar Badal Kumar Datta Plant Taxonomy and Biodiversity Laboratory Department of BotanyTripura UniversitySuryamaninagar-799130TripuraIndia Ecosystem Research Laboratory Centre for Advanced Studies in BotanySchool of Life ScienceNorth-Eastern Hill UniversityShillong-793022MeghalayaIndia

Tree species diversity and population structure at different community types were described and analyzed for primary and secondary lowland moist deciduous forests in Tripura. Overall 10,957 individual trees belonging to 46 family, 103 genera and 144 species were counted at ≥30 cm DBH （diameter at breast height） using 28 permanent belt transects with a size of 1 ha （10 m × 1000 m）. Four different tree communities were identified. The primary forests was dominated by Shorea robusta （mean density 464.77 ***^-1, 105 species） and Schima wallichii （336.25 ***^-1, 82 species）, while the secondary forests was dominated by Tectona grandis （333.88 ***^-1, 105 species） and Hevea brasiliensis （299.67 ***^-1, 82 species）. Overall mean basal area in this study was ***^-1; the maximum value was recorded in primary Shorea forest （26.21 ***^-1）. Mean density and diversity indices were differed significantly within four different communities. No significant differences were observed in number of species, genera, family and tree basal cover area. Significant relationships were found between the species richness and different tree population groups across the communities. Results revealed that species diversity and density were increased in those forests due to past disturbances which resulted in slow accumu- lation of native oligarchic small tree species. Seventeen species were recorded with 〈2 individuals of which Saraca asoka （Roxb.） de Wilde and Entada phaseoloides （L.） Men＇. etc. extensively used in local ethnomedicinal formulations. The present S. robusta Gaertn dominated forest was recorded richer （105 species） than other reported studies. Moraceae was found more speciose family instead of Papilionaceae and Euphorbiaceae than other Indian moist deciduous forests. Seasonal phenological gap in such moist deciduous forests influenced the population of Trachypithecus pileatus and capped langur. The analysis of FIV suggested a slow trend of shifting the p

关键词： diversity and stand structure moist deciduous forest species conservation tree community types

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Gas hydrate saturation from NGHP 02 LWD data in the Mahanadi Basin

Energy Geoscience

引用

Energy Geoscience 2024年第2期5卷 279-289页

作者： uma.shankar Pradeep Kumar Yadav Sneha Devi Udham Singh Yadav Department of Geophysics Institute of ScienceBHUVaranasi221005India Oil and Natural Gas Corporation Ltd. Gas Hydrate Research&Technology Centre(GHRTC)Panvel410221Navi MumbaiIndia

During the Indian National Gas Hydrate Program(NGHP)Expedition 02,Logging-while-drilling(LWD)logs were acquired at three sites(NGHP-02-11,NGHP-02-12,and NGHP-02-13)across the Mahanadi Basin in area *** applied rock physics theory to available sonic velocity logs to know the distribution of gas hydrate at site NGHP-02-11 and *** physics modeling using sonic velocity at well location shows that gas hydrate is distributed mainly within the depth intervals of 150-265 m and 100 -215 mbsf at site NGHP-02-11 and NGHP-02-13,respectively,with an average saturation of about 4%of the pore space and the maximum concentration of about 40%of the pore space at 250 m depth at site NGHP-02-11,and at site NGHP-02-13 an average saturation of about 2%of the pore space and the maximum concentration of about 20%of the pore space at 246 m depth,as gas hydrate is distributed mainly within 100-246 mbsf at this *** of gas hydrate estimated from the electrical resistivity method using density derived porosity and electrical resistivity logs from Archie's empirical formula shows high saturation compared to that from the sonic ***,estimates of hydrate saturation based on sonic P-wave velocity may differ significantly from that based on resistivity,because gas and hydrate have higher resistivity than conductive pore fluid and sonic P-wave velocity shows strong effect on gas hydrate as a small amount of gas reduces the velocity significantly while increasing velocity due to the presence of *** site NGHP-02-11,gas hydrate saturation is in the range of 15%e30%,in two zones between 150-180 and 245-265 *** NGHP-02-012 shows a gas hydrate saturation of 20%e30%in the zone between 100 and 207 *** NGHP-02-13 shows a gas hydrate saturation up to 30%in the zone between 215 and 246 *** observations from rock physics modeling and Archie’s approximation show the gas hydrate concentrations are relatively low(<4%of the pore space)at the sites of the

关键词： Mahanadi Basin Gas hydrate Sonic log Effective medium modeling Electrical resistivity log Archie’s analysis Gas hydrate saturation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Anti-proliferative and anti-angiogenic activities of ion-channel modulators:In-ovo,in-vitro and in-vivo study

引用

Asian Pacific Journal of Tropical Biomedicine 2017年第6期7卷 555-562页

作者： Chandana Kamili Ravi shankar Kakataparthy uma Maheshwararao Vattikutti Vijay Chidrawar Sindhuri Ammineni Department of Pharmacology CMR College of Pharmacy Department of Pharmacology Sri Sai Aditya Institute of Pharmaceutical Sciences and Research Department of Pharmacognosy TRR College of Pharmacy Department of Pharmacology and Toxicology Northern Border University

Objective:Angiogenesis is the development of new blood *** ion channels on endothelium play a vital action in cell proliferation and so in the related *** aimed to investigate the anti-angiogenic effects of Mefloquine(Cl-channel blocker) and4-Aminopyridine(K+ channel blocker).Methods:The anti-angiogenic activities of Mefloquine and 4-Aminopyridine(4-AP)were investigated by in-vivo(sponge implantation method),in-vitro(aortic ring assay)and in-ovo(CAM,Chick Chorioallantoic membrane) *** standard antiangiogenic drug used was ***:In the CAM assay,both the ion channel blockers exhibited noticeable antiangiogenic activity at the concentrations of 10-5M and 10-4M where they significantly exhibited ant proliferative activity by inhibiting the new blood vessel *** the further confirmation anti-angiogenic activity was evaluated in vitro and in *** Rat aortic ring assay reduction in the area of sprouts were observed with 40 m M of 4-AP and7 m M of Mefloquine.A significant reduction in weight of sponges,number of blood vessels formed and hemoglobin content were observed at 4.2 mg/kg of 4-AP and 20 mg/kg and 30 mg/kg of ***:These scientific findings indicate the use of Mefloquine and 4-Aminopyridine in pathological situations involving excessive *** regulation of cell volume,cell migration and proliferation of blood vessels may be the underlying molecular mechanisms.

关键词： Ion-channels Sponge implantation method Aortic ring assay Chick Chorioallantoic membrane

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：