Identify Plant Drought Stress by 3D-Based Image

Plants respond to drought stress with different physical manners, such as morphology and color of leaves. Thus, plants can be considered as a sort of living-sensors for monitoring dynamic of soil water content or the stored water in plant body. Because of difficulty to identify the early wilting symptom of plants from the results in 2D （two-dimension） space, this paper presented a preliminary study with 3D （three-dimension）-based image, in which a laser scanner was used for achieving the morphological information of zucchini （Cucurbita pepo） leaves. Moreover, a leaf wilting index （DLWIF） was defined by fractal dimension. The experiment consisted of phase-1 for observing the temporal variation of DLWIF and phase-2 for the validation of this index. During the experiment, air temperature, luminous intensity, and volumetric soil water contents （VSWC） were simultaneously recorded over time. The results of both phases fitted the bisector （line： 1：1） with R2=0.903 and REMS=0.155. More significantly, the influence of VSWC with three levels （0.22, 0.30, and 0.36 cm3 cm-3） on the response of plant samples to drought stress was observed from separated traces of DLWIF. In brief, two conclusions have been made： （i） the laser scanner is an effective tool for the non-contact detection of morphological wilting of plants, and （ii） defined DLWIF can be a promising indicator for a category of plants like zucchini.

ID-based authentication scheme combined with identity-based encryption with fingerprint hashing

Current identity-based （ID） cryptosystem lacks the mechanisms of two-party authentication and user＇s private key distribution. Some ID-based signcryption schemes and ID-based authenticated key agreement protocols have been presented, but they cannot solve the problem completely. A novel ID-based authentication scheme based on ID-based encrypfion （IBE） and fingerprint hashing method is proposed to solve the difficulties in the IBE scheme, which includes message receiver authenticating the sender, the trusted authority （TA） authenticating the users and transmitting the private key to them. Furthermore, the scheme extends the application of fingerprint authentication from terminal to network and protects against fingerprint data fabrication. The fingerprint authentication method consists of two factors. This method combines a token key, for example, the USB key, with the user＇s fingerprint hash by mixing a pseudo-random number with the fingerprint feature. The security and experimental efficiency meet the requirements of practical applications.