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The inverse kinematics in robot manipulator have to handle the arctangent and arccosine function. However, the two functions are complicated and need much computation time so that it is difficult to be realized in the typical processing system. The purpose of this paper is to solve this problem by using Field Programmable Gate Array (FPGA) to speed up the computation power.

The Taylor series expansion method is firstly applied to transfer arctangent and arccosine function to a polynomial form. And Look-Up Table (LUT) is used to store the parameters of the polynomial form. Then the behavior of the computation algorithm is described by Very high-speed IC Hardware Description Language (VHDL) and a co-simulation using ModelSim and Simulink is applied to evaluate the correctness of the VHDL code.

The computation time of arctangent and arccosine function using by FPGA need only 320 and 420 ns, respectively, and the accuracy is <0.01°.

Fast computation in arctangent and arccosine function can speed up the motion response of the real robot system when it needs to perform the inverse kinematics function.

This is the first time such to combine the Taylor series method and LUT method in the computation the arctangent and arccosine function as well as to implement it with FPGA.

The purpose of this paper is to find out the distribution of benefits, costs, and value added among the actors and problems in the practical management in dairy milk value chain, especially in one of the most important dairy areas in Vietnam to see how they upgrade in the value chain.

A survey was carried out in Bavi, Hanoi where a large amount of fresh milk is produced annually. The content of the survey was built before conducting in Bavi with 160 questionnaires. The questionnaires were based on the criteria which reflect the main objectives of the paper such as the actor’s profits and costs, the relationship among these actors, and the advantages and disadvantages in the dairy milk’s value chain. Some part of results of the paper was evaluated by conducting interviews with the relevant target groups in the value chain of dairy milk. Data collected were aggregated and analyzed by SPSS20, Excel. The calculation of cost and profit margin of each actor in the chain was also be presented by a quantitative tool for value chain analysis.

This study pointed out the systemized problems in the value chain of one of the biggest dairy companies in Vietnam. This study revealed some wicked problems in the value chains of Vietnam under globalization.

This study could not cover all of the detailed actors in the dairy value chain.

The value of income in the chain is distributed unequally. The benefits that farmers receive are inadequate with the costs they have to pay. This is a particular chain, in which the main factors boosting the chain are factories, and an increase in revenue also reflects the benefits of them. The result is that the value added in the chain is also biased toward the dairy plant. The paper also pointed out the shortcomings in the cost calculation of farmers. All the expenses, such as wages and the opportunity cost, are calculated in the total cost of the dairy plant, whereas dairy farmers do not mention these costs. Thus, in terms of benefits, farmers suffer more disadvantages, thus they should be received more value. In terms of management, Bavi’s authorities could not manage the output of milk in the perfect way. The lax management has led to a series of counterfeit goods that appear on the market today. These low-quality products are sold right on the highway and the Bavi’s tourist destination.

This paper aims to develop a multi-hazard risk assessment method based on probability theory and a set of economic, social and environmental indicators, which considers the increase in hazards when they occur concurrently or consecutively.

Disaster risk assessment generally considers the impact and vulnerability of a single hazard to the affected location/object without considering the combination of multiple hazards occurring concurrently or consecutively. However, disasters are often closely related, occurring in combination or at the same time. Probability theory was used to assess multi-hazard, and a matrix method was used to assess the interaction of hazard vulnerabilities.

The results of the case study for the Mid-Central Coastal Region show that the proportions of districts at a very high class of multi-hazard, multi-vulnerabilities and multi-hazard risk are 81%, 89% and 82%, respectively. Multi-hazard risk level tends to decrease from North to South and from East to West. A total of 100% of coastal districts are at high to very high multi-hazard risk classes. The research results could assist in the development of disaster risk reduction programs towards sustainable development and support the management to reduce risks caused by multi-hazard.

The multi-risk assessment method developed in this study is based on published literature, allowing to compare quantitatively multiple risk caused by multi-hazard occurring concurrently or consecutively, in which, a relative increase in hazard and vulnerability is considered. The method includes the assessment of three components of disaster risk including multi-hazard, exposure and multi-vulnerability. Probability and Copula theories were used to assess multi-hazard, and a matrix method was used to assess the interaction intensity of multi-vulnerabilities in the system.

This study aims to estimate the pass-through rate of the increases in the excise tax and TCF tax on tobacco in Vietnam. This study seeks to shed light on how the tax burden is split between consumers and producers and inform policy discussions in the country. Using panel micro-level data collected from three waves of a nationwide retailer's survey, this study provides an evidence-based pass-through estimation for tobacco tax in Vietnam and contributes to the understanding of tax policy on smoking and smoking-related issues.

Following increases in the excise tax and TCF tax on tobacco in 2019, the differential effect of the tax hike on the “treatment group” (domestic cigarettes) versus the “control group” (illicit cigarettes) using a difference-in-difference (DID) analysis has been studied. The study utilized unique longitudinal retailers’ data on cigarettes prices in Vietnam from 2018 to 2019 to estimate the tax pass-through rate for some of the most popular factory-made cigarette brands.

This study found evidence of an over-shifting of cigarette taxes on smokers. Specifically, it discovered that the tax increase is absorbed more by low-priced brand smokers compared to premium brand users due to (1) the limited increase in prices under a pure ad valorem system and (2) the way the Vietnamese currency is denominated. Additionally, there is evidence of cushioning to mitigate price shock on consumers as the real prices increase gradually over the period of one year after the tax change.

To the best of the authors’ knowledge, this study is the first to collect and analyze a unique panel micro-level data from three waves of a nationwide retailers’ survey, which captures the changes in marketing and pricing strategies of the tobacco industry in Vietnam before and after an increase in excise tax in 2019. The results of this study could be used as a reference for future policymakers in considering increasing taxes on tobacco.