Optimal operation of Hoa Binh reservoir for flood control on Hong-Thai Binh river system

In the paper the optimal operation of Hoabinh reservoir for flood control on Hong–Thai Binh river system is presented. The findings show that in the flood season in 1996 if the operation of gates and outlets of Hoa Binh reservoir was made base on the calculated release, the water level at Hanoi would be 12.3 m and the water level of Hoa Binh reservoir would be 98 m. So the calculated release from Hoabinh reservoir in August 1996 can be considered as optimal in the mean that the water level at Hanoi can be controlled and the Hoabinh reservoir still have necessary pool for controlling the next floods

Agricultural restructure policy in Vietnam and practical application for sustainable development in agriculture

Recently, effective agricultural policies necessitate sustainable development in the agricultural sector, which necessitates frequent research and the attention of policymakers. Consequently, this study investigates the effect of agricultural restructuring policies on agricultural import, agricultural export, agricultural employment, agricultural irrigation land, and agricultural land on the sustainable development of agriculture in Vietnam. From 1991 to 2021, the researchers extracted secondary data from secondary sources such as World Development Indicators (WDI). The researchers also used the non-linear autoregressive distributed lag (NARDL) method to examine the relationships between the variables. The results revealed that agricultural restructuring policies regarding agricultural import, agricultural exports, agricultural employment, agricultural irrigation land, and agricultural land have a positive correlation with Vietnam's agriculture's sustainable development. The research assists policymakers in formulating regulations for achieving sustainable agricultural development by implementing effective agricultural restructuring policies.Mai Thi Huyen (Bac Giang Agriculture and Forestry University (BAFU)), Nguyen Thi Xuan Huong (Viet Nam National University of Forestry (VNUF)), Nguyen Van Song (Viet Nam National University of Agriculture (VNUA)), Nguyen Thi Hai Yen (College of Economics, Vinh University (VU)), Nguyen Dang Que National Academy of Public Administration (NAPA))Includes bibliographical references

Quality properties Of Vietnamese cocoa liquors

Vietnam (VN) is an emerging country targeting cocoa as a potential industrial domain. It is however still unclear how the quality of VN cocoa liquors can be positioned in the world cocoa supply. Three VN cocoa liquors exhibiting high to intermediate acidity (pH: 4.7 – 5.2) were selected to produce dark chocolate (48.0% sugar, 17.6% cocoa solids, 34.0% cocoa butter and 0.4% lecithin). A comparison study was conducted to investigate the difference between VN and Ghanaian (GH; pH: 5.6) dark chocolates in terms of Casson flow properties (yield stress sCA and viscosity hCA), hardness (F 20°C and F 30°C), water-soluble organic acid content, aroma profile and sensory evaluation. The impact of pre-treatments of cocoa liquor by ball-milling at different fat contents and conching (-C) was also examined

Data assimilation method in flood forecasting for Red river system using high performent computer

Around the world, the data assimilation framework has been reported to be of great interest for weather forecasting, oceanography modeling and for shallow water flows particularly for flood model. For flood model this method is a power full tool to identify time-independent parameters (e.g. Manning coefficients and initial conditions) and time-dependent parameters (e.g. inflow). This paper demonstrates the efficiency of the method to identify time-dependent parameter: inflow discharge with a real complex case Red River. Firstly, we briefly discuss about current methods for determining flow rate which encompasses the new technologies, then present the ability to recover flow rate of this method. For the case of very long time series, a temporal strategy with time overlapping is suggested to decrease the amount of memory required. In addition, some different aspects of data assimilation are covered from this case

Rice farmers' perception and determinants of climate change adaptation measures: a case study in Vietnam

The study used Mann Kendall's and Sen's slope tests to elicit rice farmers' perceptions of climate change due to extreme weather occurrences and compared them to hydro-meteorological data. According to the findings, temperatures increased by 0.4 degrees during the last 35 years. While rainfall has increased, the pattern has been difficult to discern. The test results corroborated farmers' perceptions of increased heat spells, but rainfall frequency and intensity vary and are difficult to anticipate. Three adaptation strategies are frequently employed in the Nong Cong district: adjusting the seasonal calendar to alter transplanting and harvesting timing; increasing fertiliser and pesticide application; and changing variety to short-time kinds. Due to the interdependence of adaption techniques, the study used a multivariate probit model. The regression findings indicated that several relevant variables influence the decision to apply adaption methods. Numerous policy ideas for enhancing adaptation to climate change can be derived from the results of this study. District governments must improve their capacity to forecast weekly weather and train how to adapt production to climate change.Le Phuong Nam (Viet Nam National University of Agriculture (VNUA)), Nguyen Dang Que (National Academy of Public Administration (NAPA)), Nguyen Van Song (Viet Nam National University of Agriculture (VNUA)), Tran Thi Hoang Mai (Vinh University (VU)), Nguyen Thi Minh Phuong (Vinh University (VU)), Nguyen Thi Xuan Huong (Viet Nam National University of Forestry (VNUF)), Nguyen Cong Tiep (Viet Nam National University of Agriculture (VNUA)), Tran Ba Uan (Dien Bien Technical Economic College)Includes bibliographical references

Analysis of reproductive traits and laying egg rhythm of maize weevil sitophilus zeamais (motschulsky)

The maize weevil, Sitophilus zeamais (Motschulsky), is a serious pest affecting a wide range of cereal crops, such as maize, rice, beans and other stored dried grains. As a S. zeamais female can keep laying eggs for a long time throughout its life after chewing its way into the grains, most development stages of the maize weevil, such as eggs, larvae and pupae, can always be found in stored maize grains. Our experiment with S.  zeamais on long grain rice showed that 10 days after eclosion and mating, maize weevil females started laying eggs for a period of 145 days. On average, a S.  zeamais female laid 38.67 eggs, of which, up to 62.81% were laid in the first 7–8 weeks (with the remaining 37.19% in the latter half of the 145 day period), and 55.07%  were laid within day 55–95. The egg laying pattern of S. zeamais was modeled using cubic polynomials, which described the maximum percentages of eggs laid at day 15, 35, 75, 95 and 105.  

A Flexible Flow Sensor System and Its Characteristics for Fluid Mechanics Measurements

In this paper, we present a novel micromachined hot-film flow sensor system realized by a technique using a film depositing processes and incorporating a standard printed circuit. Sensor electrodes and electronic circuits are preprinted on a flexible substrate of polyimide (PI), i.e., a flexible printed circuit board (FPCB). The sensing element, which is made of Cr/Ni/Pt with a temperature coefficient of resistance around 2,000 ppm/K, is fabricated on the FPCB by either magnetron sputtering technology or pulsed laser deposition (PLD). The sensor can be packed efficiently at high-density and integrated with signal processing circuits without additional pads. A simple fabrication process using mature technique and materials selection guarantees that the time and costs are greatly reduced. Both steady-state and transient characteristics of the sensors are experimentally tested, and the results presented to validate the effectiveness of the sensors