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The giant panda (Ailuropoda melanoleuca) is a special rare and endangered species in China and is the flagship species for global biodiversity conservation. This study used different methods including Kernel density, statistical analysis, and logistic regression analysis to investigated the spatial distribution, migration in different seasons and different distribution areas, as well as the foraging patch selection strategies of wild giant pandas in Meigu Dafengding National Nature Reserve in the Liangshan Mountains. The results demonstrated that, in the study area, giant pandas were mainly distributed in the Wahei-Yizi Yakou Habitat Corridor with an activity area of 144.93 km2, which accounted for 28.59% of the whole reserve. The core distribution area of the species was 92.07 km2 and the population density was 0.24 pcs km–2. There were two significant seasonal domains for the activities of giant pandas: the low-altitude winter habitat of Yushania maculata Yi and Yushania ailuropodina Yi bamboo species, as well as the high-altitude summer habitat of Bashania fangiana species. With seasonal changes, giant pandas migrated among different bamboo distribution regions. Giant pandas were mainly distributed in high-altitude areas that had secondary forest, tall trees with a large diameter at breast height (DBH) and bamboo forest. The spatial distribution pattern and microhabitat selection of giant pandas in Meigu Dafengding National Nature Reserve were determined. The findings of this study provide scientific implications for the local conservation and management of the habitat of wild giant pandas.

We present a practical lattice-based fault attack against SM2 signature algorithm in a smart card. This seems to be the first combination of the lattice attack presented in SAC’2013 and fault attack against SM2 in practice. We successfully utilize the laser fault attack to skip the instructions of nonces being written into RAM, so that the nonces in signatures share partial same bits from each other. Next, we build the model of lattice attack and recover the private key. The experimental results show we only need 3 faulty signatures to mount lattice attack successfully in about 32 \(\upmu \)s. Moreover, we propose a new countermeasure for SM2 signature algorithm to resist lattice-based fault attack by destroying the condition of lattice attack rather than thwarting fault attack. It is proved the countermeasure can guarantee the ability to resist lattice attack, even if some information of the nonces is leaked.

Elliptic curve cryptosystem (ECC) is widely used in cryptographic device. Despite its solid mathematical security, ECC is still vulnerable to many kinds of physical attacks. In this paper, we present two new lattice-based differential fault attacks (DFA) against the famous ECC signature algorithm standard-ECDSA with wNAF algorithm of scalar multiplication. Compared with the fault attack proposed in Crypto’2000, our first attack adopts a different way to deduce parts of the nonce k. The former recovered parts of k mainly by guessing technique, while our attack combines the guessing technique and solving equation with one unknown. So our attack is applicable for the weaker attack scenes allowing more random faulty bits. In our second proposed attack, instead of injecting faults during calculating kG, we focus on injecting faults during calculating wNAF transformation of k before calculating kG. If the targets during wNAF transformation of k are skipped by fault injection, we can build some DFA models to retrieve parts of k. In both of the two attacks, the attacker can mount lattice attack to recover the private key in ECDSA with the derived parts of k. Finally, we verify the feasibility of our proposed attacks by experiments.

Pavement performance forecast is the foundation to do a good job of pavement maintenance management, and the accurate prediction of the premise is to create a simple and reasonable equation. At present, many countries and regions present a variety of pavement performance models. However, each model of the pavement performance has certain limitations. This paper gives a decay model of the deterioration equation for pavement performance which has simple form and clear physical significance. The model has been used in pavement preventive maintenance management system development and obtained the certificate of computer software copyright registration, (Registration Number: 2011SR066875) issued by the national copyright administration of the People's Republic of China and the reliability of the model is proved by engineering applications. The model can be used for asphalt pavement performance evaluation, maintenance priority arrangement and maintenance funds decision analysis.

An evident fault occurs on the insulator surface accompanied by a remarkable insulator strength decline were detected, which is probably caused by the SF 6 decomposition products in the insulator flashover process. A simulation of flashover process on the insulator surface was built in this article in order to analyze the possible decomposition product of SF6. As a result, several specific decomposition products (eg. CS 2 ) of the primary insulator material were discovered, which make it possible to assume the reaction mechanism and further application of insulator flashover process via analysis of specific gas such as CS 2 .

This paper studies the method of path planning for nonholonomic wheeled mobile robots in the known environments. The path planner based on optimization is proposed. This planner takes full account of the distance and angle between the robot and the target, velocity and obstacles to the navigation evaluation function, and then formulates the path planning problem in the discrete optimization problem. On the current state of robot, the range of input is determined by dynamic window, then the avoidance obstacles optimization input is solved by genetic algorithm. In this paper, the relationship of the target and obstacles is also accounted. Numerical simulations were performed to illustrate the effectiveness of the proposed planner in static, moving obstacles and dynamic object tracking, respectively.