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This study focused on mangrove cover mapping by using vegetation indices in Tien Yen district. Mangrove ecosystems play a vital role in many coastal regions, protecting against erosion and storm surges, providing nursery habitats of aquatic organisms, and offering livelihoods to local communities. Besides, this study aims to evaluate the use of PlanetScope data based on vegetation indices for mapping mangrove cover. This study collected and analyzed high-resolution PlanetScope satellite imagery (3m x 3m) to calculate eight different vegetation indices, including CMRI, NDVI, NDWI, GNDVI, BNDVI, SAVI, IPVI, and EVI2. These indices were used to map the mangrove cover in Tien Yen District and to evaluate the accuracy of each vegetation index. The results showed that among all of the indices used, NDVI had the highest accuracy of 96.3% in mapping the mangrove cover in Tien Yen district, followed by CMRI. Besides, the study emphasizes the importance of utilizing remote sensing techniques in supporting conservation efforts and establish sustainable management practices for mangrove forests in Tien Yen district. Additionally, the study presents an overview of the current situation and policy recommendations for the integrated management of mangrove forests, and provides information on sustainable mangrove ecosystem management in the context of climate change adaptation and mitigation in Tien Yen district, Quang Ninh province.

This study aimed to identify rubber clones, suitable for rubber-timber production. An experiment was established in randomized complete block design to evaluate the effects of two different planting densities on girth, girth increment, bark thickness, latex yield per tapping per tree (g/t/t), incident of tapping panel dryness disease, and wood potential of nine rubber clones, including RRIV 2, RRIV 3, RRIV 4, RRIV 5, RRIV 107, PB 235, PB 260, PB 330, and RRIC 121. Data of girth, girth increment, bark thickness were collected in the 7th year, prior to opening for tapping, and 17th year of planting. In contrast, data of latex yield were collected in the 3rd and the 11th tapping year, and wood potential was compared based on the data collected in the 11th tapping year. As a result, there were no significant interactions between clones and planting density in girth growth, latex yield, tapping panel dryness and bark thickness, and the first tapping panel (BO-1). There were no significant interactions between clone and planting density on girth growth, latex yield, tapping panel dryness, and bark thickness when these clones were tapped on the first tapping panel (BO- 1). Meanwhile, there were significant interactions between clones and planting density on girth growth, girth increment, and latex yield when the trees were tapped on the second tapping panel (BO-2). Statistical comparison of mean diameters at breast height and bole volume per tree of the same clones at two different planting densities showed that most of the studied clones gave significant differences. However, no significant differences resulted in the statistical comparison of the mean bole height of the same clones at two different planting densities. The total bole volume per hectare of all studied clones was larger at high planting density than at normal planting density. However, the bole volume per tree at high planting density was smaller than that at normal planting density. Clone RRIC 121 could be considered a suitable clone for latex and timber productions. The favorable planting density for commercial timber production is high.

By conducting interviews, summarizing and analyzing secondary documents, and employing a set of published indicators to evaluate the payment for forest environmental services (PFES), the research has examined the current status of the forest in the study area as well as the contribution of special-use and protection forests to revenue improvement from PFES. The results show that PFES in Da Bac district has high transparency, fairness and effectiveness. However, the results of the SWOT analysis demonstrate that the current situation of PFES and forest protection and development in Da Bac have been facing many difficulties and challenges, such as poor coordination among stakeholders in implementing PFES; forest protection and development with low effectiveness and consolidation; lack of forest rangers according to the provisions of law; pressure caused by natural forest exploitation activities of people living in neighboring communes outside the basin; and regularly updated technology requiring forest rangers and staff from the forest protection and development fund to quickly perceive it in order to successfully complete their tasks. Therefore, solutions have been proposed to improve the effectiveness of PFES towards sustainable forest development.

Remote sensing technology offers an effective tool to monitor the changes in land use/cover over time. This study tested five vegetation indices for land-use/cover mapping and SAVI was then selected with thresholds defined for land cover (SAVI > 0.52 for forest cover; SAVI > 0.21 and SAVI 0.05 and SAVI

Mangrove forests are found along tropical and subtropical coastlines. They have vital functions in preventing coastal erosion, mitigating effects of wave actions, and protecting coastal habitats. This study used the Sentinel-2-derived CMRI thresholds for coastal land covers (CMRI > 0.47 for mangrove forests, -0.25 < CMRI ≤ 0.47 for non-mangrove forests, and CMRI ≤ -0.25 for water bodies). The CMRI is suitable for detecting mangrove cover along the coast of Tien Yen district with overall accuracy over 90.5% and Kappa coefficient greater than 0.85 for the whole selected years. Overall, the extent of coastal mangrove forests along the coast of Tien Yen, Quang Ninh province increased by 792.7 ha in 2022 compared to 2016. Moreover, the total AGB and AGC of mangrove forests were estimated at 2,761,533 tons and 1,311,728 tons in 2022, respectively. The total CO2 sequestration was estimated at 4,814,042 tons in 2022, an increase of 1,212,632 tons compared to 2016. The study assumed the constant carbon price of US$5 ton-1 CO2, US$11 ton-1 CO2, and US$15 ton-1 CO2, the total amount of CO2 paid for Tien Yen district would be about US$6,063,160, US$13,338,952, and US$18,189,480, respectively. The study highly suggests that mangrove blue carbon should be adopted and implemented toward sustainable mangrove management in Tien Yen district, including mangrove PES schemes. However, some key factors should be clearly addressed to ensure the success of mangrove blue carbon option in Tien Yen district, including an increased awareness of the value of mangrove ecosystem promoted; the involvement of local communities encouraged; other issues in relation to PES policy revised.

Mangroves are found along shallow shorelines with modest slope where they receive freshwater runoff and nutrients from rainfall. They have been globally recognized as their vital functions in preventing coastal erosion, mitigating effects of wave actions and protecting coastal habitats from extreme coastal events. By using PlanetScope imageries (3mx3m), the study has constructed the spatial distribution of mangrove forests from 2017 to 2022. This study defined and used the CMRI thresholds for coastal land covers (CMRI value > 0.835 for mangrove forests, CMRI

Chemical investigation of the leaves and stems of Dioscorea bulbifera resulted in isolation of 10 compounds, including three new norclerodane diterpenoids, diosbulbiferins A (1) and B (2) and diosbulbiferinoside A (3), and one new natural congener, diosbulbiferin C (4), along with one new tetrahydrophenanthrene, diosbulbinone (8). Their structures were elucidated by comprehensive analyses of spectroscopic methods, including NMR and mass spectra. The absolute configurations of compounds 1-3 and 8 were deduced by time-dependent density functional theory (TD-DFT) electronic circular dichroism (ECD) spectroscopic analyses. In addition, cytotoxic effects against MCF-7, HepG2, and SK-Mel-2 cancer cells and in vitro anti-inflammatory effects of the isolated compounds in LPS-stimulated BV2 microglial cells were also reported.

A well-known result of Montel states that for a family F of meromorphic functions in a domain D ⊂ C , if there exist three distinct points a 1 , a 2 , a 3 in C ˆ and positive integers l 1 , l 2 , l 3 such that 1 l 1 + 1 l 2 + 1 l 3 1 and all zeros of f − a i have multiplicity at least l i for all f ∈ F and i ∈ { 1 , 2 , 3 } , then F is normal in D. Inspired by this classical result, during the past 100 years, a large number of normality criteria have been established for the case where meromorphic functions (or differential polynomials generated by the members of the family) meet some distinct points with sufficiently large multiplicities. This means that these criteria strictly apply only to the case in which derivatives of functions (differential polynomials, respectively) vanish on respective zero sets. In this paper, we generalize some normality criteria of Montel, Grahl–Nevo, Gu, and Bergweiler–Langley to the case where derivatives are bounded from above on zero sets.

An analysis is carried out for solidification around a cold cylinder in a rectangular cavity using numerical simulations. The transient influences of solidification accompanied by natural convection are investigated in detail. The governing equations, in terms of one-fluid formulation, including the Navier-Stokes and energy equations for incompressible Newtonian fluids are written for the whole domain. The no-slip and Dirichlet-type isothermal temperature boundary conditions are both implemented using a linear interpolation technique (immersed boundary method). The solidification interface is represented by connected elements that move on the fixed background grid. Code validations are carried out through various problems. Finally, the temporal dependence of the solid area ratio of the solid phase to the cylinder upon various dimensionless parameters, such as Rayleigh number, Prandtl number, Stefan number, thermal property ratios as well as a parameter indicating the effect of superheat is studied.

In this paper, direct numerical simulations are presented for solidification with the effects of density difference between the solid and liquid phases. A front-tracking method is used. The solidification front, i.e. the solid-liquid interface separating solid and liquid, is represented by connected elements that move on a rectangular and stationary grid. The Navier-Stokes equations are solved by a projection method on the entire domain including the solid phase. An indicator function reconstructed from the front information is used to set the velocities in the solid phase to zero, and thus to enforce the no-slip condition at the interface. The method is validated through comparisons with exact solutions for one- and two-dimensional problems. The method is then used to simulate the solidification processes with the effects of volume change due to density difference

In the current classification problems, how to eliminate redundant features, find out important features, and choose appropriate classifiers for these feature set play a vital role. This paper presents a co-operative co-evolution approach (COCEA) with dual populations for optimizing both the artificial neural network (ANN) model and feature subset selection simultaneously. In COCEA, each feature subset is encoded as a binary string. Meanwhile, an ANN is represented in a matrix-form with real values of its weight and bias. During the process of evolution, a co-Operation mechanism is used to integrate the two populations and the final solution is the combination of the two most elite individuals of each population in a hope that the final solution will satisfy both ANN optimization and feature subset selection. The performance of COCEA is examined on both the well-known benchmark problems and Oil Spill dataset in SAR Images. In comparison with the other algorithms, experimental results illustrate that COCEA can significantly outperform other peer algorithms in terms of classification accuracy.

The objective of this research is to investigate the effect of various parameters on rapid prototyping parts during the process of sintering metal powder by using fiber laser. In order to minimize the percentage of porosities of rapid prototyping (RP) products, sintering a mixture of three metallic powders are investigated. Three metallic powders which are used in this research are Cooper, Iron and Nickel (particle size of Cooper is 5μm, Iron is 70μm and Nickel is 70μm). In addition, control factors and their alternate levels-two levels with 48 run experiments will be identified. The Design of Experiment (DOE) and Analysis of Variance (ANOVA) are used to analyze the results of modeling process. After the ANOVA, a regression model predicting percentages of porosities under various conditions was developed when the traditional Taguchis approach failed to identify a feasible model due to strong interactions of controlled factors.

Time series forecasting is paid a considerable attention of the researchers. At present, in the field of machine learning, there are a lot of studies using an ensemble of artificial neural networks to construct the model for time series forecasting in general, and consumer price index (CPI) forecasting, in particular. However, determining the number of members of an ensemble is still debatable. This paper proposes the way of constructing a model for CPI forecasting and designing a multi-objective evolutionary algorithm in training neural networks ensembles in order to increase the diversity of the population. Two objectives of the training problem include: Mean Sum of Squared Errors and diversity. We experimented the model on three data sets and compared methods. The experimental results showed that the proposed model produced better in investigated cases.

Germplasm collections have provided original materials for plant breeding program and crop improvement. Because of their genetic diversity and possible occurrence of particular desirable genes, germplasm collections are useful targets for plant breeders as well as other biologists. Recently, many of germplasm are being lost worldwide due to habitat destruction, invasion of foreign species, and reliance on fewer high yielding strains. Therefore, maintaining germplasm of agricultural crops is very important. Normally, a germplasm collection will be utilized based on its characters of immediate perceived value or its potential variation. Furthermore, it can also be used to better understand the properties and performances of the plants, particularly at the genomic level. Nowadays, countries all over the world have set up facilities for conservation, characterization and utilization of germplasm collections of various crops either directly or indirectly.

In 1985, Fujimoto established a non-integrated defect relation for meromorphic maps of complete Kähler manifolds into the complex projective space intersecting hyperplanes in general position. In this paper, we generalize the result of Fujimoto to the case of meromorphic maps into a complex projective variety intersecting hypersurfaces in general position., Oberwolfach Preprints;2010,19

In this paper, using techniques of Nevanlinna theory, we give a degeneracy theorem of meromorphic mappings of C m into C P n with few hyperplanes and truncated multiplicities.