A new inverse trigonometric shear deformation theory for isotropic and functionally graded sandwich plates

A new inverse trigonometric shear deformation theory is proposed for the static, buckling and free vibration analyses of isotropic and functionally graded (FG) sandwich plates. It accounts for a inverse trigonometric distribution of transverse shear stress and satisfies the traction free boundary conditions. Equations of motion obtained here are solved for three types of FG plates: FG plates, sandwich plates with FG core and sandwich plates with FG faces. Closed-form solutions are obtained to predict the deflections, stresses, critical buckling loads and natural frequencies of simply supported plates. A good agreement between the obtained predictions and the available solutions of existing shear deformation theories is found to demonstrate the accuracy of the proposed theory

Trichinellosis in Vietnam

Trichinellosis is a zoonotic parasitic disease with a worldwide distribution. The aim of this work was to describe the epidemiological and clinical data of five outbreaks of trichinellosis, which affected ethnic minorities living in remote mountainous areas of northwestern Vietnam from 1970 to 2012. Trichinellosis was diagnosed in 126 patients, of which 11 (8.7%) were hospitalized and 8 (6.3%) died. All infected people had consumed raw pork from backyard and roaming pigs or wild boar at wedding, funeral, or New Year parties. The short incubation period (average of 9.5 days), the severity of the symptoms, which were characterized by diarrhea, abdominal pain, fever, myalgia, edema, weight loss, itch, and lisping, and the high mortality, suggest that patients had ingested a high number of larvae. The larval burden in pigs examined in one of the outbreaks ranged from 70 to 879 larvae/g. These larvae and those collected from a muscle biopsy taken from a patient from the 2012 outbreak were identified as Trichinella spiralis. Data presented in this work show that the northern regions of Vietnam are endemic areas for Trichinella infections in domestic pigs and humans

High Hydrogen Evolution Reaction (HER) and Hydrogen Oxidation Reaction (HOR) Activity RhxSy Catalyst Synthesized with Na2S for Hydrogen-Bromine Fuel Cell

A RhxSy/C catalyst with high mass-specific electrochemical surface area (ECSA/mass), high hydrogen oxidation reaction (HOR)/hydrogen evolution reaction (HER) activity, and high Nafion® ionomer-affinity was synthesized and evaluated. A new sulfur source, Na2S instead of (NH4)2S2O3, was applied to prepare the rhodium sulfide precursor Rh2S3 that resulted in a RhxSy catalyst with higher HOR/HER catalytic activity after thermal treatment. The higher activity was attributed to the higher quantity formation of the more active phase Rh3S4, in addition to the other active Rh17S15 phase, in the RhxSy catalyst. Using this new sulfur source, carbon substrate functionalization, and the mass-transfer-controlled nanoparticle growth process, the average particle size of this catalyst was reduced from 13.5 nm to 3.2 nm, and its ECSA/mass was increased from 9.3 m2/g-Rh to 43.0 m2/g-Rh. Finally, by applying the Baeyer–Villiger and ester hydrolysis process to convert the Nafion® ionomer-unfriendly ketone group on the carbon support surface to the Nafion ionomer-friendly carboxylic group, which increases the Nafion® affinity of this catalyst, its use in the hydrogen electrode of an H2-Br2 fuel cell resulted in a performance that is 2.5× higher than that of the fuel cell with a commercial RhxSy catalyst

OPPORTUNITIES AND CHALLENGES IN PROMOTING THE ROLE OF INTERNATIONAL INTEGRATION FOR SOCIO-ECONOMIC DEVELOPMENT IN VIETNAM

International integration is an objective trend, strongly attracting the participation of all countries and regions in the world. International integration is strongly affecting all nations, all aspects of socio-economic life. For Vietnam, international integration has brought opportunities and good chances, while it also posed real challenges and risks in promoting the role of the state in the socio-economic development. Therefore, the urgent issue at the present is to identify fully, deeply and to figure out reasonable strategies, to take advantage of opportunities, to overcome risks in order to promote the role of international integration for socio-economic development in Vietnam with important theoretical and practical meanings.  Article visualizations

Fixed Point Theorems for g-Monotone Maps on Partially Ordered S-Metric Spaces

In this paper, we prove some fixed point theorems for g-monotone maps on partially ordered S-metric spaces. Our results generalize fixed point theorems in [1] and [7] for maps on metric spaces to the structure of S-metric spaces. Also, we give examples to demonstrate the validity of the results

Fixed Point Theorems for g-Monotone Maps on Partially Ordered S-Metric Spaces

In this paper, we prove some fixed point theorems for g-monotone maps on partially ordered S-metric spaces. Our results generalize fixed point theorems in [1] and [7] for maps on metric spaces to the structure of S-metric spaces. Also, we give examples to demonstrate the validity of the results

Study on model for cutting force when milling SCM440 steel

This article presents empirical study results when milling SCM440 steel. The cutting insert to be used was a TiN coated cutting insert with tool tip radius of 0.5 mm. Experimental process was carried out with 18 experiments according to Box-Behnken matrix, in which cutting speed, feed rate and cutting depth were selected as the input parameters of each experiment. In addition, cutting force was selected as the output parameter. Analysis of experimental results has determined the influence of the input parameters as well as the interaction between them on the output parameters. From the experimental results, a regression model showing the relationship between cutting force and input parameters was built. Box-Cox and Johnson data transformations were applied to construct two other models of cutting force. These three regression models were used to predict cutting force and compare with experimental results. Using parameters including coefficient of determination (R-Sq), adjusted coefficient of determination (R-Sq(adj)) and percentage mean absolute error (% MAE) between the results predicted by the models and the experimental results are the criteria to compare the accuracy of the cutting force models. The results have determined that the two models using two data transformations have higher accuracy than model not using two data transformations. A comparison of the model using the Box-Cox transformation and the model using the Johnson transformation was made with a t-test. The results confirmed that these two models have equal accuracy. Finally, the development direction for the next study is mentioned in this articl