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The State-Funded Landslide Project (SFLP) is a national program to systematically assess landslide susceptibility, hazard and risk for all of prone areas in Vietnam. Under this SFLP, in the first phase of SFLP (2012SFLP ( -2014, activities of landslide inventory mapping were implemented over the fourteen Northern mountainous provinces. As the achievements, 10,149 historic landslides were mapped by field surveys and 9405 locations with landslide signs were interpreted from air-photos and analysis of 3D relief. Approximately 83% of the surveyed landslides locate in accessible areas, with small and medium dimensions and partly as a result of the slope cuts. About 76% of the interpreted landslides locate in inaccessible areas, and only 24% of the interpreted locate in accessible areas, of which 65% were found active landslides at the time of surveying, naturally occurred with large dimensions. However, the inventory exposes some major drawbacks: (1) The unavailability of multi-date air-photos; (2) The lack of human resources with enough experiences in image interpretation; (3) The difficulties of verifying the interpreted landslides, especially for the inaccessible sites; (4) Few or no sources of historic information due to the isolated sites or little memory of small or medium size events; (5) No updates developed by the surveyors after they finished their tasks. Those drawbacks can lead to the insufficiency of adequate data on the types, sizes and characteristics of the slope failures, especially the exact dates of occurrences. Despite of those difficulties, the achieved inventory database have been updated and then used as basic input for the susceptibility and hazard mapping as well as preliminary results of SFLP to inform the local authorities and communities about real situations of landslides in their areas.

Integrating wind power and solar power plants into a power system has significantly grown over the past decade and is expected to grow to unprecedented levels in the coming years. In Vietnam, much large-scale wind power and solar power plants have been built and connected to the power system in recent years. To investigate and evaluate the impact of these power plants on system power operation, the 110kV power transmission network of Binh Dinh province in Vietnam is used in this paper. In the system, the Phuong Mai 3 wind power plant with a capacity of 21MW, the Fujiwara solar power plant with a peak capacity of 50MWp, and the Cat Hiep solar power plant with a peak capacity of 49.5MWp are modeled by using the PSS/E software to simulate and analyze their impacts on power system stability of the 110kV transmission network in Binh Dinh province, Vietnam. Besides, the control strategies of these power plants are also established to investigate their impacts on the network. In addition, this paper proposes three typical scenarios for the wind power and solar power plants in the system. For each scenario, the grid's operating parameters such as voltage variations and frequency variations are acquired for analyzing and evaluating their impacts on the frequency and voltage variations of the network. The simulation results show that the 110kV power transmission network remains in a stable operation mode after the fault scenarios for the wind and solar power plants. Furthermore, these simulation results provide some guidance for the actual operation

Currently, with the disappearance of fossil energy sources, finding new alternative energy sources is very necessary such as: solar energy, wind energy, tidal energy, flow energy, ... However, these energy sources require high investment capital, large capacity, and bulky size. In circuits requiring small power sources (below 12V), it is not applicable, or only used through intermediate devices such as transformers, current transformers; Therefore, the application of energy from mechanical vibration has been proposed as an optimal measure compared to the above methods..Energy recovery from mechanical vibration is the activity of reusing a part of the energy generated when there is a fluctuation with a constant frequency on solid surfaces.Mechanical vibrations occur mostly in production systems, and it also causes some damage.However, we can take advantage of these mechanical vibrations to cater for some basic life requirements if they have the right vibration frequency and amplitude, or we can adjust to have optimal vibration conditions.This article uses an intermediate control circuit to convert the energy generated by mechanical vibration into electrical energy (current and voltage), in which the piezoelectric sensors or piezoelectric beam are placed on the structures to be measured, we will receive oscillations at different frequencies, so that we can analyze the damage caused by vibration and evaluate the application range of piezoelectric sensors and piezoelectric beam on a case-by-case basis. The purpose of the paper is to study a constant frequency energy recovery circuit to create some initial parameters,the use a Bond-Graph to optimally simulate this energy recovery process. This is also a very good solution for generating energy for the SHM system from other mechanical energy sources.

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