We consider the problem of the two-point resistance on an m ×n cobweb network with a 2r boundary, which has never been solved before. Up to now researchers just only solved the cases with free boundary or null re...We consider the problem of the two-point resistance on an m ×n cobweb network with a 2r boundary, which has never been solved before. Up to now researchers just only solved the cases with free boundary or null resistor boundary. This paper gives the general formulae of the resistance between any two nodes in both tinite and infinite cases using a method of direct summation pioneered by Tan [Z. Z. Tan, et al., J. Phys. A 46 （2013） 195202], which is simpler and can be easier to use in practice. This method contrasts the Green＇s function technique and the Laplacian matrix approach, which is difllcult to apply to the geometry of a cobweb with a 2r boundary. We deduce several interesting results according to our genera/formula. In the end we compare and illuminate our formulae with two examples. Our analysis gives the result directly as a single summation, and the result is mainly composed of the characteristic roots.展开更多
Behavioral plasticity has been proposed as a means by which animals alter their phenotypes in response to changing conditions.Animals may display behavioral plasticity as a consequence of environmental variation.The d...Behavioral plasticity has been proposed as a means by which animals alter their phenotypes in response to changing conditions.Animals may display behavioral plasticity as a consequence of environmental variation.The detritus-based,bell-shaped cobweb spider Campanicola campanulata is an ideal model to study behavioral plasticity,because its web architecture is easy to be quantified,and the functions of different parts of the web are clear.Though the plasticity of cobweb architecture has been reported in a few species,retreats as impor-tant defensive structures have rarely been considered before because retreats in most cobwebs are relatively small compared with the web size.We studied the web-building behaviors of C.campanulata under different feeding regimes.We set up 3 spider treatments with different feeding conditions:marginally well fed,moderately well fed,and extremely well fed,and observed the differences in the web architecture among them.In addition,we measured the mechanical properties of anchor silk,and also calculated the foraging and defense investment of the spiders.The results showed that marginally well-fed spiders build cobwebs with significantly longer length of anchor silk,lower retreat to the ground,more number and longer gumfooted lines,and larger capture area,while extremely well-fed spiders build cobwebs with significantly bigger retreat volume and higher height of retreat to the ground.In addition,marginally well-fed spiders invest significantly less during cobweb construction.However,there was no significant difference between the breaking force and elongation at break in anchor silk among different treatments.These results demonstrated that marginally well-fed spiders invest more in foraging,and extremely well-fed spiders invest more in defense,and the spider made a balance between foraging and predator avoidance in response to changes in physiological state.Our study strengthens the current understanding of web construction in cobweb spiders,especially those facing high costs during retreat construction.展开更多
A novel cobweb-like disk resonator gyroscope(CDRG)is introduced in this paper,which integrates a multi-bit electromechanical sigma-delta modulation(ΣΔΜ)system to significantly expand the input angular rate signal r...A novel cobweb-like disk resonator gyroscope(CDRG)is introduced in this paper,which integrates a multi-bit electromechanical sigma-delta modulation(ΣΔΜ)system to significantly expand the input angular rate signal range,improving performance metrics like signal-to-noise ratio(SNR)and noise reduction.This design seeks to overcome the limitations associated with single-bitΣΔΜgyroscope systems by incorporating a linear multi-bit force feedback mechanism that utilizes nonlinear actuators driven by pulse density modulation.The proposed gyroscope system effectively broadens the input range without necessitating higher actuation voltages.In the absence of electronic trimming,experimental findings indicate significant enhancements in performance metrics:the input range,angle random walk,and bias instability improved by 30%,106.2%,and 487.9%,respectively,when compared to traditionalΣΔΜCDRG system configurations.展开更多
文摘We consider the problem of the two-point resistance on an m ×n cobweb network with a 2r boundary, which has never been solved before. Up to now researchers just only solved the cases with free boundary or null resistor boundary. This paper gives the general formulae of the resistance between any two nodes in both tinite and infinite cases using a method of direct summation pioneered by Tan [Z. Z. Tan, et al., J. Phys. A 46 （2013） 195202], which is simpler and can be easier to use in practice. This method contrasts the Green＇s function technique and the Laplacian matrix approach, which is difllcult to apply to the geometry of a cobweb with a 2r boundary. We deduce several interesting results according to our genera/formula. In the end we compare and illuminate our formulae with two examples. Our analysis gives the result directly as a single summation, and the result is mainly composed of the characteristic roots.
基金supported by grants from the National Natural Sciences Foundation of China(NSFC-31970406/31801979/31772420/31573236/32270495)a grant from National Science&Technology Fundamental.Resources Investigation Program of China(Grant No.2019FY101800)+1 种基金CAS Key Laboratory of Tropical Forest Ecology,Xishuangbanna Tropical of Botanical Garden,Chinese Academy of Sciences(19CAS-TFE-3)a grant from the State Key Laboratory of Integrated Management of Pest Insects and Rodents,Institute of Zoology,Chinese Academy of Sciences(Grant No.IPM2208).
文摘Behavioral plasticity has been proposed as a means by which animals alter their phenotypes in response to changing conditions.Animals may display behavioral plasticity as a consequence of environmental variation.The detritus-based,bell-shaped cobweb spider Campanicola campanulata is an ideal model to study behavioral plasticity,because its web architecture is easy to be quantified,and the functions of different parts of the web are clear.Though the plasticity of cobweb architecture has been reported in a few species,retreats as impor-tant defensive structures have rarely been considered before because retreats in most cobwebs are relatively small compared with the web size.We studied the web-building behaviors of C.campanulata under different feeding regimes.We set up 3 spider treatments with different feeding conditions:marginally well fed,moderately well fed,and extremely well fed,and observed the differences in the web architecture among them.In addition,we measured the mechanical properties of anchor silk,and also calculated the foraging and defense investment of the spiders.The results showed that marginally well-fed spiders build cobwebs with significantly longer length of anchor silk,lower retreat to the ground,more number and longer gumfooted lines,and larger capture area,while extremely well-fed spiders build cobwebs with significantly bigger retreat volume and higher height of retreat to the ground.In addition,marginally well-fed spiders invest significantly less during cobweb construction.However,there was no significant difference between the breaking force and elongation at break in anchor silk among different treatments.These results demonstrated that marginally well-fed spiders invest more in foraging,and extremely well-fed spiders invest more in defense,and the spider made a balance between foraging and predator avoidance in response to changes in physiological state.Our study strengthens the current understanding of web construction in cobweb spiders,especially those facing high costs during retreat construction.
基金supported in part by the National Key Research and Development Program of China under Grant No.2022YFB3205000 and 2022YFB3205004in part by the National Natural Science Foundation of China under Grant No.61974156,61504159,and 61674160+1 种基金in part by the Natural Science Foundation of Hunan province(2025jj50082)the Key Project of Hunan Provincial Department of Education(24A0291).
文摘A novel cobweb-like disk resonator gyroscope(CDRG)is introduced in this paper,which integrates a multi-bit electromechanical sigma-delta modulation(ΣΔΜ)system to significantly expand the input angular rate signal range,improving performance metrics like signal-to-noise ratio(SNR)and noise reduction.This design seeks to overcome the limitations associated with single-bitΣΔΜgyroscope systems by incorporating a linear multi-bit force feedback mechanism that utilizes nonlinear actuators driven by pulse density modulation.The proposed gyroscope system effectively broadens the input range without necessitating higher actuation voltages.In the absence of electronic trimming,experimental findings indicate significant enhancements in performance metrics:the input range,angle random walk,and bias instability improved by 30%,106.2%,and 487.9%,respectively,when compared to traditionalΣΔΜCDRG system configurations.
