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Abstract Objective: SEANUTS II Vietnam aims to obtain an in-depth understanding of the nutritional status and nutrient intake of children between 0·5 and 11·9 years old. Design: Cross-sectional survey. Setting: A multistage cluster systematic random sampling method was implemented in different regions in Vietnam: North Mountainous, Central Highlands, Red River Delta, North Central and Coastal Area, Southeast and Mekong River Delta. Participants: 4001 children between 6 months and 11·9 years of age. Results: The prevalence of stunting and underweight was higher in rural than in urban children, whereas overweight and obese rates were higher in urban areas. 12·0 % of the children had anaemia and especially children 0·5–1 year old were affected (38·6 %). Low serum retinol was found in 6·2 % of children ≥ 4 years old. The prevalence of vitamin D insufficiency was 31·1 % while 60·8 % had low serum Zn. For nutrient intake, overall, 80·1 % of the children did not meet the estimated energy requirements. For Ca intake, ∼60 % of the younger children did not meet the RNI while it was 92·6 % in children >7 years old. For vitamin D intake, 95·0 % of the children did not meet recommended nutrient intakes. Conclusions: SEANUTS II Vietnam indicated that overnutrition was more prevalent than undernutrition in urban areas, while undernutrition was found more in rural areas. The high prevalence of low serum Zn, vitamin D insufficiency and the inadequate intakes of Ca and vitamin D are of concern. Nutrition strategies for Vietnamese children should consider three sides of malnutrition and focus on approaches for the prevention of malnutrition.

The paper discusses the length to beam (L/B) ratio effects on ship resistance at three different Froude numbers using unsteady RANSE simulation. First, the JBC ship model was used as an initial hull form for verification and validation of predicted ship resistance results with measured data, and then the influence of the L/B ratio on ship resistance was carried out. Ship hull forms with different L/B ratios were produced from the initial one by using the Lackenby method. The numerical results obtained show the L/B ratio’s effect on ship resistance. Increases of the L/B ratio led to gradual reduction of the total ship resistance and vice versa. Analysis of the changing of the resistance components indicates that the pressure resistance changes are considerably larger than the frictional one. Finally, the paper analyses the difference in the flow field around the hull of the ship with variation of the L/B ratio to fully understand the physical phenomenon in the change of ship resistance at different L/B parameters.

This paper deals with the results of studying the effect of trim on the performance of series cargo ship 12500DWT in full scale at two operating conditions by using the RANSE method. The Body Force Propeller method is used to simulate a rotating propeller behind the ship. The numerical predicted results at the ballast condition were verified and validated with sea trial data. The ship’s engine power curves for different trim conditions at two operating conditions were carried out to produce a data source to evaluate the effect of trim on the performance of the 12500DWT cargo ship. The results indicate that if the ship operates under optimum trim conditions, this can decrease the ship’s engine power in a range from 2.5 to 4.5% depending on different loading conditions and ship speeds. Finally, the paper also provides detailed differences in flow around the ship due to trim variation to explain the physical phenomenon of changing ship performance.

On inland waterways the ship resistance and propulsive characteristics are strictly related to the depth of the waterway, thus it is important to have an understanding of the influence of water depth on ship hydrodynamic characteristics. Therefore, accurate predictions of hydrodynamic forces in restricted waterways are required and important. The aim of this paper is investigating the capability of the commercial unsteady Reynolds–Averaged Navier–Stokes (RANS) solver to predict the influence of water depth on ship resistance. The volume of fluid method (VOF) is applied to simulate the free surface flow around the ship. The hull resistance in shallow and deep water is compared. The obtained numerical results are validated against related experimental studies available in the literature.