THE VARIATION OF QUALITY AND CURRENT SITUATION OF ARSENIC IN THE PLEISTOCENE AQUIFER- MEKONG DELTA

Joint Research on Environmental Science and Technology for the Eart

Having an Older Brother Is Good or Bad for Your Education And Health? Evidence from Vietnam

This study examines the sex of the first-born children on education and health outcome of later born children. We do not find a significant effect of the sex of the first-born children on health utilization of later born children. However, we find some small effects of education. Once controlled for the number of sibling, having a firstborn brother reduces the probability of school enrolment and the probability of having good academic performance. Although the education outcomes of girls are higher than boys, this evidence still indicates gender bias in education investment of parents in their children in Vietnam

Having an Older Brother Is Good or Bad for Your Education And Health? Evidence from Vietnam

This study examines the sex of the first-born children on education and health outcome of later born children. We do not find a significant effect of the sex of the first-born children on health utilization of later born children. However, we find some small effects of education. Once controlled for the number of sibling, having a firstborn brother reduces the probability of school enrolment and the probability of having good academic performance. Although the education outcomes of girls are higher than boys, this evidence still indicates gender bias in education investment of parents in their children in Vietnam

On a feedback-feedforward identification control algorithm for feedback active controlled structures

Linear quadratic regulator (LQR) is an effective method of feedback active control theory. However, the LQR control is not truly optimal because it is only a feedback algorithm, i.e. the external excitation term is ignored in the optimal equation. In a previous paper [1], the identification algorithm is presented for feedback active controlled systems to identify the excitation from the structural response measured. The aim of this paper is to propose a feedback-feedforward control algorithm using the identified excitation to improve the classical LQR control. A numerical simulation is applied to an eight story building subjected to base acceleration and controlled by active mass damper system

An extension of the identification algorithm for feedback active control of incomplete measured systems

In a previous paper [1], the identification algorithm is presented for feedback active controlled systems. However, this method can only be applied to complete measured systems. The aim of this paper is to present a combination of the identification algorithm and the modal superposition method to control the incomplete measured systems. The system response is expanded by modal eigenfunction technique. The external excitation acting on some first modes is identified with a time delay and with a small error depending on the sensor locations. Then the control forces will be generated to balance the identified excitations. A numerical simulation is applied to an eight story building subjected to base acceleration

Effect of plant growth regulators on growth and lipid accumulation of microalgal Haematococcus pluvialis Flotow in two-stage culture

Haematococcus pluvialis cells were cultured in aerated liquid Bold’s Basal medium in two-stage (initial stage during in 7 weeks for increased biomass growth and second stage during in 3 weeks for increased lipid accumulation) with different volumes 250 mL, 10 L, and 1,000 L. With a volume of 250 mL, the medium was supplied with benzyl adenine (BA), indole-3-acetic acid (IAA) or gibberellic acid (GA3) at concentration from 0.1 - 0.2 mg/L in initial stage and IAA or GA3 at concentration from 0.1 - 0.2 mg/L in second stage. After 10 weeks of culture, results showed that supplement of 0.1 mg/L BA in initial stage and 0.125 mg/L IAA in second stage increased cell density, and microalgal cells had green color with a spherical shape. On the contrary, supplement of 0.15 mg/L IAA in initial stage and 0.175 mg/L GA3 in second stage increased lipid accumulation, and microalgal cells had red color with a spherical shape. With a volume of 10 L, the medium was supplied with 0.1 mg/L BA in initial stage, and treated with separation or combination from 2 - 3 of these factors (nitrogen starvation, 0.5% NaCl, 4.98 mg/L FeSO4) were applied in second stage. The result showed that the cultures was treated with nitrogen starvation increased dry biomass and biofuel, but treated with 4.98 mg/L FeSO4 only increased biofuel. With a volume of 1,000 L, microalgal cells were cultured in BB liquid medium in initial stage, and treated with 4.98 mg/L FeSO4 increased fresh 78.67 mg/mL and dry biomass 2.05 mg/L and total lipid content 28.24 %/ DW