Wireless Sensor Network(WSNs)consists of a group of nodes that analyze the information from surrounding regions.The sensor nodes are responsible for accumulating and exchanging information.Generally,node local-ization...Wireless Sensor Network(WSNs)consists of a group of nodes that analyze the information from surrounding regions.The sensor nodes are responsible for accumulating and exchanging information.Generally,node local-ization is the process of identifying the target node’s location.In this research work,a Received Signal Strength Indicator(RSSI)-based optimal node localization approach is proposed to solve the complexities in the conventional node localization models.Initially,the RSSI value is identified using the Deep Neural Network(DNN).The RSSI is conceded as the range-based method and it does not require special hardware for the node localization process,also it consumes a very minimal amount of cost for localizing the nodes in 3D WSN.The position of the anchor nodes is fixed for detecting the location of the target.Further,the optimal position of the target node is identified using Hybrid T cell Immune with Lotus Effect Optimization algorithm(HTCI-LEO).During the node localization process,the average localization error is minimized,which is the objective of the optimal node localization.In the regular and irregular surfaces,this hybrid algorithm effectively performs the localization process.The suggested hybrid algorithm converges very fast in the three-dimensional(3D)environment.The accuracy of the proposed node localization process is 94.25%.展开更多
An overview of plant surface structures and their evolution is presented.It combines surface chemistry and architecture with their functions and refers to possible biomimetic applications.Within some 3.5 billion years...An overview of plant surface structures and their evolution is presented.It combines surface chemistry and architecture with their functions and refers to possible biomimetic applications.Within some 3.5 billion years biological species evolved highly complex multifunctional surfaces for interacting with their environments:some 10 million living prototypes(i.e.,estimated number of existing plants and animals)for engineers.The complexity of the hierarchical structures and their functionality in biological organisms surpasses all abiotic natural surfaces:even superhydrophobicity is restricted in nature to living organisms and was probably a key evolutionary step with the invasion of terrestrial habitats some 350–450 million years ago in plants and insects.Special attention should be paid to the fact that global environmental change implies a dramatic loss of species and with it the biological role models.Plants,the dominating group of organisms on our planet,are sessile organisms with large multifunctional surfaces and thus exhibit particular intriguing features.Superhydrophilicity and superhydrophobicity are focal points in this work.We estimate that superhydrophobic plant leaves(e.g.,grasses)comprise in total an area of around 250 million km^2,which is about 50%of the total surface of our planet.A survey of structures and functions based on own examinations of almost 20,000 species is provided,for further references we refer to Barthlott et al.(Philos.Trans.R.Soc.A 374:20160191,1).A basic difference exists between aquatic nonvascular and land-living vascular plants;the latter exhibit a particular intriguing surface chemistry and architecture.The diversity of features is described in detail according to their hierarchical structural order.The first underlying and essential feature is the polymer cuticle superimposed by epicuticular wax and the curvature of single cells up to complex multicellular structures.A descriptive terminology for this diversity is provided.Simplified,the functions of plant surface characteristics may be grouped into six categories:(1)mechanical properties,(2)influence on reflection and absorption of spectral radiation,(3)reduction of water loss or increase of water uptake,moisture harvesting,(4)adhesion and nonadhesion(lotus effect,insect trapping),(5)drag and turbulence increase,or(6)air retention under water for drag reduction or gas exchange(Salvinia effect).This list is far from complete.A short overview of the history of bionics and the impressive spectrum of existing and anticipated biomimetic applications are provided.The major challenge for engineers and materials scientists,the durability of the fragile nanocoatings,is also discussed.展开更多
Self-cleaning surfaces have received a great deal of attention recently,both in theoretical studies and commercial applications.The self-cleaning surface of lotus leaf is hydrophobic and rough,showing a micro-and nano...Self-cleaning surfaces have received a great deal of attention recently,both in theoretical studies and commercial applications.The self-cleaning surface of lotus leaf is hydrophobic and rough,showing a micro-and nano-scale morphology.The micro-reliefs of lotus leaf were mimicked using polyvinylidene fluoride(PVDF)film and nano-scale peaks on the top of the micro-reliefs were implemented by the reaction between methyltrichlorosilane and the reactive groups of PVDF film treated by oxygen plasma.A lotus-leaf-like surface of the PVDF film was clearly observed by scanning electronic microscopy(SEM)and atomic force microscope(AFM).Elemental composition analysis by X-ray photoelectron spectroscopy(XPS)revealed that the material of the nanostructure of PVDF film was polymethylsiloxane.The superhydrophobic property of the mimicked self-cleaning surface was validated by the water contact angle and sliding angle on the lotus-leaf-like PVDF film,which were 156.6° and 4°,respectively.In this case,water droplets can easily move across the PVDF film surface,carrying dirt particles away,leaving no contamination.展开更多
基金appreciation to King Saud University for funding this research through the Researchers Supporting Program number(RSPD2024R918),King Saud University,Riyadh,Saudi Arabia.
文摘Wireless Sensor Network(WSNs)consists of a group of nodes that analyze the information from surrounding regions.The sensor nodes are responsible for accumulating and exchanging information.Generally,node local-ization is the process of identifying the target node’s location.In this research work,a Received Signal Strength Indicator(RSSI)-based optimal node localization approach is proposed to solve the complexities in the conventional node localization models.Initially,the RSSI value is identified using the Deep Neural Network(DNN).The RSSI is conceded as the range-based method and it does not require special hardware for the node localization process,also it consumes a very minimal amount of cost for localizing the nodes in 3D WSN.The position of the anchor nodes is fixed for detecting the location of the target.Further,the optimal position of the target node is identified using Hybrid T cell Immune with Lotus Effect Optimization algorithm(HTCI-LEO).During the node localization process,the average localization error is minimized,which is the objective of the optimal node localization.In the regular and irregular surfaces,this hybrid algorithm effectively performs the localization process.The suggested hybrid algorithm converges very fast in the three-dimensional(3D)environment.The accuracy of the proposed node localization process is 94.25%.
基金supported by the Deutsche Bundesstiftung Umwelt DBUthe German Research Council DFG+1 种基金the Federal Ministry for Science and Education BMBFthe Academy of Science and Literature in Mainz
文摘An overview of plant surface structures and their evolution is presented.It combines surface chemistry and architecture with their functions and refers to possible biomimetic applications.Within some 3.5 billion years biological species evolved highly complex multifunctional surfaces for interacting with their environments:some 10 million living prototypes(i.e.,estimated number of existing plants and animals)for engineers.The complexity of the hierarchical structures and their functionality in biological organisms surpasses all abiotic natural surfaces:even superhydrophobicity is restricted in nature to living organisms and was probably a key evolutionary step with the invasion of terrestrial habitats some 350–450 million years ago in plants and insects.Special attention should be paid to the fact that global environmental change implies a dramatic loss of species and with it the biological role models.Plants,the dominating group of organisms on our planet,are sessile organisms with large multifunctional surfaces and thus exhibit particular intriguing features.Superhydrophilicity and superhydrophobicity are focal points in this work.We estimate that superhydrophobic plant leaves(e.g.,grasses)comprise in total an area of around 250 million km^2,which is about 50%of the total surface of our planet.A survey of structures and functions based on own examinations of almost 20,000 species is provided,for further references we refer to Barthlott et al.(Philos.Trans.R.Soc.A 374:20160191,1).A basic difference exists between aquatic nonvascular and land-living vascular plants;the latter exhibit a particular intriguing surface chemistry and architecture.The diversity of features is described in detail according to their hierarchical structural order.The first underlying and essential feature is the polymer cuticle superimposed by epicuticular wax and the curvature of single cells up to complex multicellular structures.A descriptive terminology for this diversity is provided.Simplified,the functions of plant surface characteristics may be grouped into six categories:(1)mechanical properties,(2)influence on reflection and absorption of spectral radiation,(3)reduction of water loss or increase of water uptake,moisture harvesting,(4)adhesion and nonadhesion(lotus effect,insect trapping),(5)drag and turbulence increase,or(6)air retention under water for drag reduction or gas exchange(Salvinia effect).This list is far from complete.A short overview of the history of bionics and the impressive spectrum of existing and anticipated biomimetic applications are provided.The major challenge for engineers and materials scientists,the durability of the fragile nanocoatings,is also discussed.
基金Tianjin Municipal Science and Technology Commission,China(No.06YFJZJC14802)
文摘Self-cleaning surfaces have received a great deal of attention recently,both in theoretical studies and commercial applications.The self-cleaning surface of lotus leaf is hydrophobic and rough,showing a micro-and nano-scale morphology.The micro-reliefs of lotus leaf were mimicked using polyvinylidene fluoride(PVDF)film and nano-scale peaks on the top of the micro-reliefs were implemented by the reaction between methyltrichlorosilane and the reactive groups of PVDF film treated by oxygen plasma.A lotus-leaf-like surface of the PVDF film was clearly observed by scanning electronic microscopy(SEM)and atomic force microscope(AFM).Elemental composition analysis by X-ray photoelectron spectroscopy(XPS)revealed that the material of the nanostructure of PVDF film was polymethylsiloxane.The superhydrophobic property of the mimicked self-cleaning surface was validated by the water contact angle and sliding angle on the lotus-leaf-like PVDF film,which were 156.6° and 4°,respectively.In this case,water droplets can easily move across the PVDF film surface,carrying dirt particles away,leaving no contamination.
