It’s often found in the internet that the cryptosystem can be divided into two parts, symmetric encryption system and asymmetric encryption system. The key which is used in the cryptosystem is a fixed set recently, but there are deficiencies in security. If someone try to crack the code, it is easy to make the key unsafe after a long time that resulting in the secret information leakage. The experiment was carried out using Matlab mathematics software by elliptic curve cryptography, and, tested through ZigBee facilities of the wireless transmission systems. The original used key can change automatically in server, and produces lots of sets at once in this paper. Therefore, the cryptosystem can be used for long. When we transmit the information every time, the changing key will increase the difficulties that may be cracked every time. We can increase the safety and do not increase the extra computed complexities.

This study primarily used the Taguchi test production parameters to analyze the correlation between the commercial application properties (compressive strength, volatile components and calorific value) of environmentally friendly fuel derived from wood chip gasification carbon black and the production conditions (adhesive, molding temperature and molding pressure),then, the optimal application conditions are sought.\n The results showed that the optimal production conditions were the addition of 4% PVA-1000 adhesive and the production of derivative fuels with current commercial product specifications at a molding temperature of 151 ° C and a molding pressure of 132 kg/cm2.

This paper presents a ZMP calculation method based on internal stress to handle the balance of a class of biped robots. Considering foot-ground contact environment complexly caused zero-moment point (ZMP) error too large during the walking process of the biped robot, a ZMP ideal calculation model has been developed, then the axial stress and shear stress on the vertical section of the sole material is utilized to reconstruct internal stress biped robot ZMP calculation formula, and in order to verify for the errors produced by the new calculation formula, four different ground-crash simulation experiments has been designed and compared. Based on the evolution of the ZMP trajectories, the internal-stress ZMP calculation method can effectively predict the ZMP position of biped robot under natural walking without torque sensor. With the experimental value is compared with the actual value, the average distance error is minimum between the actual and the experimental value at the foot height 20mm has been proved theoretically. We have conducted experimental studies on a biped robot to demonstrate the effectiveness of the proposed calculation method.

Solar panel electricity systems capture solar energy through photovoltaic cells, which do not require direct sunlight to produce energy, because they generate electricity on cloudy days. These cells transform sunlight into electricity that can be used to illuminate areas that do not have access to electrical fluid. However, when installing a solar panel system, you must know the electrical power required to supply a specific need and select appropriate components that allow you to extend the life of the system to be installed. Therefore, the objective of this research is to develop a methodological guide to define the specifications of equipment to be used in a solar panel system. The research was documentary and applied, because it was carried out taking into account information contained in books, articles and scientific publications. As a result, a methodological guide was obtained to define the components to be used in a solar panel system, which guarantees a series of steps that provide as a result solutions tailored to the needs of installing a photovoltaic system

Renewable energy is a fundamental way to mitigate climate change because the accelerated development of sustainable energy technology is relevant to replace conventional energy sources. There are different types of renewable energy, one of which is solar energy that uses sunlight to produce electricity through solar panels. However, in the installation of a solar panel system, the design of the system is often not taken into account, therefore the maximum performance of the system is not used. Considering the above, the purpose of the research was to develop a software program for the design of solutions with solar panel systems. The type of research was qualitative and applied, with action research design and practical approach. As a result, a software program was obtained to design a solution of a solar panel system that allows taking advantage of the maximum performance of the system to be installed.