41 research outputs found
Application of Wireless Power Transmission Led Lighting System in Propagation of Chrysanthemum and Strawberry
Contemporary horizontal crustal movement estimation for northwestern Vietnam inferred from repeated GPS measurements
Nonlinear constrained optimizer and parallel processing for golden block line search
Generalized exponential penalty functions are constructed for the multiplier methods in solving nonlinear programming problems. The non-smooth extreme constraint Gext is replaced by a single smooth constraint Gs by using the generalized exponential function (base a>1). The well-known K.S. function is found to be a special case of our proposed formulation. Parallel processing for Golden block line search algorithm is then summarized, which can also be integrated into our formulation. Both small and large-scale nonlinear programming problems (up to 2000 variables and 2000 nonlinear constraints) have been solved to validate the proposed algorithms
Gas thermodynamic conditions of cold air entrainment by natural smoke exhaust system in case of compartment fire
Conditions of occurrence of abnormal operation of natural smoke exhaust system are analyzed when cold air is entrained into smoke exhaust windows preventing extraction of smoked heated gas layer beneath a ceiling (also known as plugholing). Analytical equation is derived for prediction of critical average volumetric temperature of gas layer beneath a ceiling when plugholing starts with consideration for the height of smoke exhaust window. This equation was compared with published experimental data and with numerical experiments using 3D field model of fire gas thermodynamics. It was found that the height of smoke exhaust window exerts significant influence on occurrence of plugholing and on maximum bulk flow rate of combustion products extracted from compartment via the window. © 2020, Institute of Advanced Scientific Research, Inc.. All rights reserved
Active Flatness Control of Membrane Structures Using Fuzzy Logic Integrated Genetic Algorithm
Synthesis and cytotoxicity of dibenzo[(γ-aryl)pyridino]aza-17-crown-5 ethers
For the development of new anticancer agents, dibenzo[(γ-aryl)pyridino]aza-17-crown-5 ethers containing 2,4,6-triarylpyridine were synthesized successfully by one-step domino-condensation of 1,8-bis(2-acetylphenoxy)-3,6-dioxaoctane, arylaldehydes and ammonium acetate according to the conditions of Hantzsch reactions. The synthesized γ-arylpyridine derivatives show high cytotoxic activity against human cancer cell lines: Hep-G2, RD, FL, Lu1. Compounds (3b,c) showed significant cytotoxicity against all four human cell lines whereas the similar synthesized compound (3d) possessed cytotoxicity against HepG2, Lu1 and RD cell lines. Meantime, both compounds (3f,g) containing γ-heteroaryl only exhibited cytotoxicity against RD and FL cell lines. Azacrown ethers (3b-d) exhibited low activity on the Vero cell line, meaning that they can be evaluated for their potential as promising anticancer agents. X-Ray structure study was performed to determine the structure of the representative compound 3a. © ISUCT Publishing
Diversity, distribution and threats of the Juglandaceae in Vietnam
Vietnam is one of the main centers of generic diversity for Juglandaceae worldwide. In this study, we
present for the first time a province-wide distribution of all 3 subfamilies, 7 genera, and 11 Vietnamese species,
and give an update on the habitats of all Vietnamese Juglandaceae species, their uses, and current threats.
Juglandaceae are found throughout Vietnam. However, most species occur predominantly in the north-
ern part of the country between 600 and 1200 m. Some taxa range is found extensively from sea level up
to 2,500 meters above sea level. According to the IUCN Red List, Rhoiptelea chiliantha, Carya sinensis, and
Pterocarya tonkinensis are threatened while Engelhardia spicata, E. serrata, Alfaropsis roxburghiana, Pterocarya
stenoptera are classified as least concerned (Carya tonkinensis is threatened locally, and Engelhardia spicata
var. colebrookiana and Platycarya strobilacea merit “threatened” designation in Vietnam’s Red Data Book. The
most frequent threats are logging, land-use change, and habitat destruction due to artificial wood planta-
tions or road construction. Until now, no conservation measures have been applied for any of the species in
Vietnam, although some species occur in national parks.
Our study gives an important update on the current diversity and distribution of Juglandaceae in Vietnam.
We point out the need for a correct assessment of the threat status of various species on a national and
international scale to protect the rarest and most endangered of them. Further research, the use of various
forms of protection of individual taxa and/or their habitats, and drawing the attention of an international
group of researchers to the urgent need to work together to protect biodiversity in Vietnam hot spots are
necessary