TÍNH TOÁN CHỈ SỐ GIÁ TRỊ KINH TẾ HỆ SINH THÁI VÙNG BIỂN ĐẢO CỒN CỎ

Based on ecosystem values of coastal waters in Con Co island estimated in the national project coded KC09.08/11-15, indices of ecosystem values were developed and calculated with three components: direct use value index (Idev) of 40.2, indirect use value index (Iidev) of 55.2 and non-use value index (Inuv) of 100. An index of the total ecosystem economic value (Ieev) for the studied area was calculated at 65.1, equal to 370,350 million VND per year at present. At assessment scale of 100 points with one forth interval, economic values of coastal ecosystems of Con Co island are high.Giá trị kinh tế của hệ sinh thái biển vùng đảo Cồn Cỏ ước tính trong đề tài KC09.08/11-15 được chuyển thành các chỉ số giá trị kinh tế hệ sinh thái với những giá trị cụ thể theo ba hợp phần: Giá trị sử dụng trực tiếp hệ sinh thái - Idev = 40,2, giá trị sử dụng gián tiếp - Iidev = 55,2 và giá trị phi sử dụng - Inuv = 100. Tổng giá trị kinh tế hệ sinh thái (Ieev) cũng được tính toán và bằng 65,1 tương ứng với tổng giá trị kinh tế từ 267.519 triệu đồng/năm đến 370.350 triệu đồng/năm trong giai đoạn hiện tại. So sánh với thang đánh giá 100 điểm theo khoảng một phần tư, giá trị kinh tế hệ sinh thái vùng biển đảo Cồn Cỏ hiện đang ở mức cao

Identification and estimation of the marine ecosystem services surrounding selected offshore islands of Vietnam

Intertidal and larger marine ecosystems surrounding the islands of Bach Long Vi (Northern Vietnam), Con Co (Central Vietnam) and Tho Chu (Southernmost Vietnam) which have typical and valuable ecosystems are planned as marine protected areas. They are the study area of this paper on identification and estimation of these ecosystem services. The total economic valuation concept is used to estimate the total value of the ecosystems during the period March 2014 to October 2015. The marine ecosystems surrounding Bach Long Vi Island were estimated servicing 599,047.8 million VND (Vietnam Dong)/year in total (corresponding to 26.62 million USD (US dollar—1 USD = 22,503.68 VND (rate May 1, 2015)); calculated per hectare; this value corresponds with 94 million VND/year. The marine ecosystems surrounding Con Co Island provide a total monetary service of 267,518 million VND/year (approximately, 12 million USD/year); this corresponds with 307 million VND/ha/year. The marine ecosystems surrounding the Tho Chu archipelago were worth 565,236 million VND/year (approximately, 25 million USD/year); this corresponded with 125.47 million VND/ha/year. These figures show the most significant service value of marine ecosystems, particularly around the three islands

Determinants Influencing Vietnamese Farmers’ Intention in Applying New Technologies in Agricultural Farming

This paper used survey data from 273 farmers planting fruit trees in 23 provinces to assess the impact of some factors on the intention of applying new technologies to agricultural production of Vietnamese farmers. Research results have identified and measured a number of factors that have a positive impact and some negative factors hinder farmers' intention to apply new technologies. These findings are the basis to recommend policies and solutions to promote Vietnamese farmers to apply new technologies. Keywords: Agricultural farming; Applicability, Belief; Benefit; Market demand; Communication DOI: 10.7176/EJBM/12-6-06 Publication date: February 29th 2020

Influence of the Frequency-chirp on Pulse in Passively Mode-locking Optical Fiber Ring Laser

We consider a model of a passively mode-locking fiber ring laser bult using a saturable absorber and a chirped fiber Bragg grating to balance dispersion and nonlinearity. The evolution of the slowly envelope of the optical field in a loop fiber subject to dispersion , Kerr nonlinearity, frequency- chirp and nonlinear absorption is given by the generalized complex Ginzburg-Landau equation. The influence of the frequency-chirp on the pulse is simulated and discussed, and the stationary conditions concerning the chirp parameter are  found out for our laser

The role of green finance, eco-innovation, and creativity in the sustainable development goals of ASEAN countries

Recently, sustainable development has become a global requirement. Every country strives to achieve this essential goal, and this attracts the attention of researchers and policymakers. This study investigates the impact of green finance, eco-innovation, and creativity on the sustainable development goals in ASEAN countries. Using CUP-FM and CUP-BC techniques, the study examines the association between variables, and finds that green finance (such as green credit), renewable energy production, eco-innovation, and creativity, have positive associations with sustainable development goals. The control variable, economic growth, has a negative association with sustainable development goals. Based on the evidence, the ASEAN region must increase the quantity of green bonds as a part of green finance. This financial measure would guarantee adequate returns for private investors

COMPARATIVE STUDY ON VOLATILE COMPOUNDS OF AGARWOOD FROM KHANH HOA PROVINCE EXTRACTED BY DIFFERENT METHODS

Agarwood from Aquilaria crassna cultivated in Khanh Hoa province was extracted by 5 methods, including simple, enzyme-assited, and microwave-assisted hydrodistillation, extraction with solvent and supercritical carbon dioxide. The volatile compounds of the products were analyzed by GC-MS. Almost all samples contain some common characteristic components, such as Valerianol, Agarospirol, Eudesmol b-, Eudesmol 10-epi-g-, 2-Allyl-4-methylphenol, Guaiol and Neopetasone. However, there were obvious differences in yields, composition, and number of identified components. The application of the more advanced methods for the extraction of agarwood resulted in saving of time and energy, and some improvement of product yield. However, these methods also lead to unconventional products with many unknown components, what requires further investigations

SWIPT-enabled cooperative wireless IoT networks with friendly jammer and eavesdropper: Outage and intercept probability analysis

Physical layer security (PLS) and simultaneous wireless information and power transfer (SWIPT) in cooperative relaying have gained great interest as technologies for security and energy enhance ment in Internet-of-Things (IoT) networks. In this work, we investigate PLS for a SWIPT- and AF-enabled cooperative wireless IoT system, consisting of one source, multiple energy harvesting (EH) relays, and one destination, in the presence of an eavesdropper that tries to overhear the confidential information. Furthermore, an EH-friendly jammer is deployed to transmit jamming signals aimed at the eavesdropper to improve the security system. In this context, a low-complexity, sub-optimal, but efficient relay selection method is proposed. More specifically, the relay is selected to convey information such that it has the best channel to the source. Based on the proposed system model, the performance analysis of the intercept probability (IP), asymptotic IP, and non-zero secrecy probability (NZSP) is analyzed by considering the time switching (TS)-based relaying strategy. Particularly, the exact closed-form expression of IP is achieved by applying modified Bessel function expansion. Monte-Carlo simulations are employed to corroborate the correctness and efficiency of our mathematical analysis. The time splitting factor α makes variations on the IP of about 3× as α ∈ [0.1, 0.8]. However, a dramatic reduction of the IP up to 317× is observed as α increases from 0.8 to 0.9.Web of Science11861778616

Security and Reliability Analysis of Satellite-Terrestrial Multi-Relay Networks with Imperfect CSI

This work investigates the security and reliabil- ity analysis for a novel satellite-terrestrial (SatTer) network. Specifically, a satellite attempts to transmit confidential infor- mation to a ground user (GU) via the support of multiple relay nodes in the presence of an eavesdropper that tries to overhear the information. A friendly jammer is deployed to improve the secure transmission between the satellite and the relays. Furthermore, satellite-to-relay generalized Rician fading channels and imperfect channel state information (CSI) are deployed to examine a general system model. In this context, the closed-formed expressions for the outage probability (OP) and intercept probability (IP) are derived corresponding to an amplify-and-forward (AF)-based relaying scheme, which is challenging and has not been studied before. Finally, the exactness of the mathematical analyses is validated through Monte Carlo simulations. Furthermore, the effects of various key parameters (e.g., channel estimation errors, satellite’s transmit power, relay’s transmit power, number of relays, and fading severity parameter) are examine

Structure and Electrochemical Impedance of LiNix_{x}Mn2−x_{2 - x}O4_{4}

Ni-substitution spinel LiNixMn2−xO4 (x = 0, 0.1, 0.2) materials were synthesized by the sol--gel method. The structure and  morphology of the samples were characterized by the X-ray diffraction (XRD)  and the scanning electron microscopy. The ac conduction of the materials was  investigated by electrochemical impedance spectroscopy (EIS) measurements.  The refinement results showed that the substitution of Ni decreased the  lattice constant and Mn--O distance, while increased Li--O bond length and  16c octahedral volume. The EIS results confirmed the decrease of  conductivity with increasing Ni substitution content. Based on XRD and EIS  results, the relationship between the crystal structure and electrochemical  behavior of the materials was discussed and explained

A Phase 2/3 double blinded, randomized, placebo-controlled study in healthy adult participants in Vietnam to examine the safety and immunogenicity of an inactivated whole virion, alum adjuvanted, A(H5N1) influenza vaccine (IVACFLU-A/H5N1)

Abstract Background A global shortfall of vaccines for avian influenza A(H5N1) would occur, especially in low- and-middle income countries, if a pandemic were to occur. To address this issue, development of a pre-pandemic influenza vaccine was initiated in 2012, leveraging a recently established influenza vaccine manufacturing capacity in Vietnam. Methods This was a Phase 2/3, double-blinded, randomized, placebo-controlled study to test the safety and immunogenicity of IVACFLU-A/H5N1 vaccine in healthy adults. Phase 2 was a dose selection study, in which 300 participants were randomized to one of the three groups (15 mcg, 30 mcg, or placebo). Safety and immunogenicity were assessed in all participants. In Phase 3, 630 participants were randomized to receive the IVACFLU-A/H5N1 vaccine dose selected in Phase 2 (15 mcg, n = 525) or placebo (n = 105). Safety was assessed in all Phase 3 participants and immunogenicity was measured in a subset of participants. Results The vaccine was well tolerated and most of the adverse events were mild and of short duration. Mild pain at the injection site was the most common adverse event seen in 60 percent of participants in the vaccine group in Phase 3. In Phase 2, both 15 mcg and 30 mcg doses were immunogenic, so the lower dose was selected for further testing in Phase 3. In Phase 3 overall seroconversion rates were 68 percent for hemagglutination inhibition (HI), 51 percent for microneutralization (MN) and 56 percent for single radial hemolysis (SRH). The seroprotection rates were 44 percent for HI, 41 percent for MN and 55 percent for SRH. The GMT ratio was 5.31 and 3.7 for HI and MN respectively; GMA was 4.75 for the SRH. Conclusion The IVACFLU A/H5N1 was safe and immunogenic. Development of this pandemic avian influenza vaccine is a welcome addition to the limited global pool of these vaccines. ClinicalTrials.gov register NCT02612909