Böcker av Hung Nguyen

Recently, climate change is the key issue that the world has to face. Renewable energy is considered as a potential technology to stop the global warming and also meet the energy demand. However, renewable sources are unstable and therefore need a conversion method to store electricity generated. Solar liquid fuel is a possible method to store renewable energy in liquid form. This research project concentrates to solar to liquid fuel. Formic acid is chosen as a case study. The project will demonstrate the technology that convert solar energy into formic acid and store at the ambient conditions. The simulations will compute the electricity generated by PV system in daily and monthly and the mass of formic acid could be produced by using solar energy. The two-axis solar tracking system is simulated for the PV panels. Two important parameters of the two-axis solar tracker are investigated: the elevation angle and Azimuth angle. The results will be illustrated in tables and figures. The research also considers the application of formic acid in direct formic acid fuel cell.

# BEST VIETNAMESE FAIRY TALE COLLECTIONVietnamese fairy tales are stories that are transmitted orally in folklore by Vietnamese people to tell imaginary stories revolving around a number of characters, events, gods and even animals.Fairy tales were born in a class-divided society. They mention and care about unhappy characters first, so the basic function of fairy tales is to comfort, encourage and defend the weak, upholding human qualities. Therefore, through each fairy tale, the working people convey their dreams of a good world and of justice. They are highly educational, each story is a lesson in morality, behavior, fairness, etc. However, they often carry elements of myth and fantasy. Vietnamese fairy tales are considered as fiction and anonymous, although some stories may be explanations for certain things and phenomena in life, they are not considered as scientific evidence which belongs to the category of Vietnamese culture.Despite being born for a long time, Vietnamese fairy tales are still loved and read by readers today. The readers are not only from Vietnam but also from many parts of the world. In order to help Vietnamese fairy tales reach more readers and spread good meanings, I decided to publish this Vietnamese fairy tales book and try to make the words and plot of the fairy tales are most similar to the original. Hope to be well received by the readers.

Speaking test topics chosen according to the test-takers' area of expertise can be used to assess their speaking abilities to talk about general background knowledge or their academic subject areas. Recent studies have indicated that the topic choice affects testing performance on the oral tests, but provided inclusive results regarding the effect of general and specific-field topics on the test takers' oral performance. The aim of this research study is to investigate what type of oral assessment instruments and more specifically what topics and tasks might be best for the purpose of assessing Vietnamese faculty's oral English proficiency in the academic workplace. The results showed no significant difference in the faculty speaking performance on the general and academic field-specific topics. The findings of the research have important implications for assessing oral production in specific-purpose language testing and for providing information about the needs of Vietnamese faculty for training in spoken English for the academic workplace.

This book introduces various coverage control problems for mobile sensor networks including barrier, sweep and blanket.