Flexible strain sensors fabricated using aligned carbon nanofiber membranes with cross-stacked structure for extensive applications

Carbon nanofibers(CNFs)with excellent conductivity and stability have become a promising material to design the strain sensing network.To date,however,the effect of the stacked structure of CNF membrane on the sensing performance has rarely been stu-died.In this work,we reported a high-performance sensor based on the cross-stacked aligned CNF membrane.The effects of crossstacked structures on the sensing characteristics were systemati-cally investigated.The flexible strain sensor could capture low detection limit(<0.1%)with a gauge factor(GF)of 4.24 and wide strain range up to 130%.The uniform GF value reached 2050 when the strain was in the range of 100-130%.In addition,the high linearity under 40%strain(>0.998),excellent durability and quick response time(<200 ms)were demonstrated.The excellent com-prehensive performances were simultaneously obtained.The sen-sor could be used in extensive applications,such as monitoring body movements and distinguishing the track of writing.

Extension of TOPMODEL Applications to the Heterogeneous Land Surface

At present, the Topographic Index Model （TOPMODEL） has been recommended for integration in Land Surface Models （LSMs）. But, the applicable scope of the original TOPMODEL （OTOP） is limited because the OTOP derivation relies on three fundamental but unrealistic assumptions. In this paper, several versions of a generalized TOPMODEL （GTOP）, which relax some unrealistic assumptions involved in OTOP, are presented, and the theoretical derivationsn to obtain these modifications are demonstrated in detail. Specifically, the extension for the OTOP applicability comes down to following three basic cases： （1） Give up the assumption of spatially uniform recharge rate to the groundwater and let the rate be spatially varying, （2） Keep same original exponential distribution profile of hydraulic conductivity used in OTOP but change the saturated hydraulic conductivity and effective soil depth from spatial constants in OTOP to spatially variable quantities; and （3） Extend the original exponential distribution profile of hydraulic conductivity to more general power law distribution profile of hydraulic conductivity together with spatially variable saturated hydraulic conductivity and effective soil depth. Finally, a brief numerical sensitivity study based on one version of GTOP using an exponential distribution profile for soil hydraulic conductivity is conducted. This shows the heterogeneous effects of the effective soil depth, saturated hydraulic conductivity, at ground surface and groundwater recharge rate on hydrological processes and serves as an example application of GTOP to a heterogeneous catchment.

THE APPLICATION AND EXTENSION OF SACHS METHOD

In this paper,we present the simplification of Sachs formulas for the measurement and calculation of the residual stresses of the cylinder only with the plane stresses. Furthermore, we present the method for the measurement and calculation of the residual stresses of the cylinder not only with the finite length but with the longitudinal stress. These can be applied to the investigation on the residual stresses of the autofretted gun tube.