Tourism Finance: Investing and Financing in Sustainable Tourism

This study addresses the big problem that tourism projects and initiatives are encountering. Lack of financing is a common challenge hindering the development of tourism, resulting to a number of popular destinations that are slowly dying (e.g. the Great Wall of China, and the Angkor Wat). The purpose of Tourism Finance is to set criteria on which value-adding tourism projects should receive investment funding; and to evaluate a tourism organization’s financial needs to better decide on what capital structure (i.e., debt and/or equity) to appropriately raise to minimize the weighted average cost of capital. The method of this research is using qualitative research method with techniques of data collection by literature study and that were conducted by discussing seven potential sources of travel and tourism financing. Output, the result of this research is recommendations for leader in travel and tourism in improving the performance of tourism finance, investments to maintain the financial sustainability of organizations (i.e., business, non-profit and government) involved in the travel and tourism sectors

Factors affecting the profitability of food companies listed on the Vietnam stock market

The study aims to determine the factors affecting the profitability of the food companies listed on the Vietnam stock market. The study uses panel data with 198 observations of 22 food companies listed on the Vietnamese stock market in the period 2011-2019 into the regression analysis. With 3 methods POLS, FEM and REM; the author uses F test and Hausman test to select the appropriate model. The result show that REM is the most optimal model selected. However, the REM model still has variable variance defects and endogenous variables; therefore, the author uses GMM method to overcome the defects of the model. The results from the GMM regression model show that the profitability of food companies listed on the Vietnamese stock market is affected by internal factors including size, risk, past profitability, leverage, and macro factors such as: economic growth, inflation, calamity. From there, the author proposes recommendations to improve the profitability of these enterprises

PURIFICATION OF PHOSPHOGYPSUM FOR USE AS CEMENT RETARDER BY SULPHURIC ACID TREATMENT

Phosphogypsum is a by-product of the wet phosphoric acid production. In this study, chemical compositions of phosphogypsum waste (PG) in Hai Phong diammonium phosphate plant (DAP1) and Lao Cai diammonium phosphate plant (DAP2) in Vietnam were surveyed for the purpose of gypsum recovery by P2O5, F removal to meet TCVN11833 for use treated gypsum as cement retarder. Studies of impurities P2O5, F, TOC removal by sulfuric acid 10 % at 28 0C was presented. The results found that the combination of a low concentration of sulfuric acid treatment, washing, lime neutralizing, and thermal treatment was successful in Phoshogypsum treatment for use as cement retarder. The cement test proved that treated PG could partially replace natural gypsum as a retarder.Keywords:  phosphogypsum treatment, phosphorus pentoxide removal, calcium sulfate transition phase, cement retarder.

Phytoremediation of heavy metal polluted soil and water in Vietnam

Phytoremediation has been intensively studied during the past decade due to its cost-effectiveness and environmental harmonies. Most of the studies on treatment of heavy metal pollution in soil and water by plant species have been done in developed countries but are limited in Vietnam. In this study, we presented some research results of phytoremediation of polluted soils and water with heavy metals that were done by Institute of Environmental Technology for several last years. For treatment of heavy metal pollution in the water, some plants have great ability to accumulate heavy metals such as Vetiveria zizanioides, Phragmites australis, Eichhornia crassipes, Pistia stratiotes, Ipomoea aquatica, Nypa fruticans and Enhydra fluctuans. The heavy metal uptake into shoots and roots of 33 indigenous plant species in Thai Nguyen province was also determined. Two species of the plants investigated, Pteris vittata L. and Pityrogramma calomelanos L. were As hyperaccumulators, containing more than 0.1% As in their shoots while Eleusine indica, Cynodon dactylon, Cyperus rotundus and Equisetum ramosissimum accumulated very high Pb (0.15-0.65%) and Zn (0.22-1.56%) concentrations in their roots. Some experiments to clarify the potential of several plants as good candidates for phytoremediation of polluted soil by heavy metals were carried out in our institute.Phương pháp sử dụng thực vật để xử lý ô nhiễm đã được nghiên cứu nhiều trong thập kỷ qua do chi phí thấp và thân thiện với môi trường. Hầu hết các nghiên cứu về xử lý ô nhiễm kim loại nặng trong đất và nước bằng thực vật đã được thực hiện ở các nước phát triển nhưng ít có tại Việt Nam. Trong nghiên cứu này, chúng tôi giới thiệu một số kết quả dùng công nghệ thực vật để xử lý ô nhiễm kim loại nặng trong đất và nước tại Viện Công nghệ môi trường trong những năm gần đây. Dối với xử lý ô nhiễm kim loại nặng trong nước, một số thực vật có khả năng tích lũy tốt kim loại nặng như Vetiveria zizanioides, Phragmites australis, Eichhornia crassipes, Pistia stratiotes, Ipomoea aquatica, Nypa fruticans và Enhydra fluctuans. Sự hấp thụ và tích lũy kim loại nặng trong phần trên mặt đất và rễ của 33 loài thực vật bản địa tại Thái Nguyên cũng đã được xác định. Hai loài thực vật khảo sát là Pteris vittata và Pityrogramma calomelanos là những loài siêu tích lũy As, chứa hơn 0,1% As trong phần trên mặt đất của cây. leusine indica, Cynodon dactylon, Cyperus rotundus và Equisetum ramosissimum tích lũy Pb (0,15-0,65%) và Zn (0,22-1,56%) rất cao trong rễ. Một số thí nghiệm đánh giá tiềm năng của một số thực vật là đối tượng tốt cho xử lý ô nhiễm kim loại nặng trong đất đã được tiến hành trong phòng thí nghiệm của Viện Công nghệ môi trường

Diverse Ceramic Technologies in Neolithic Southern Vietnam: The Case of Rach Nui

The initial appearance of fine, incised, and impressed ceramics dating to the Neolithic period (4200–3000 B.P.) in southern Vietnam was associated with the emergence and spread of sedentary settlements, cereal agriculture, and new forms of material culture. However, differences existed in contemporary ceramic technologies between sites. This article presents a preliminary characterization of the pottery found at Rach Nui, a habitation site with an economy focused on vegeculture and foraging that was located at the confluence of the Vam Co Dong, Dong Nai, and Vam Co Tay rivers. The rim forms and decorations at Rach Nui are presented alongside a characterization of the tempers and clays from a small sample of sherds using scanning electron microscopy and energy dispersive X-ray spectrometry (SEM-EDX). The Rach Nui ceramics are compared to previous studies of pottery from An Son, located upstream on the Vam Co Dong River. The results of the characterization and comparison indicate that Rach Nui potters focused on local production of a limited range of vessels compared to primarily agricultural settlements like An Son. This research on Rach Nui pottery demonstrates that by ca. 3500 B.P., the inhabitants of the various Neolithic settlements of southern Vietnam, and perhaps more broadly across Mainland Southeast Asia, had established their own social and cultural traditions that were reflected in locally specific ceramic technologies

Role of seasonal importation and genetic drift on selection for drug-resistant genotypes of Plasmodium falciparum in high-transmission settings

Historically Plasmodium falciparum has followed a pattern of drug resistance first appearing in low-transmission settings before spreading to high-transmission settings. Several features of low-transmission regions are hypothesized as explanations: higher chance of symptoms and treatment seeking, better treatment access, less within-host competition among clones and lower rates of recombination. Here, we test whether importation of drug-resistant parasites is more likely to lead to successful emergence and establishment in low-transmission or high-transmission periods of the same epidemiological setting, using a spatial, individual-based stochastic model of malaria and drug-resistance evolution calibrated for Burkina Faso. Upon controlling for the timing of importation of drug-resistant genotypes and examination of key model variables, we found that drug-resistant genotypes imported during the low-transmission season were (i) more susceptible to stochastic extinction due to the action of genetic drift, and (ii) more likely to lead to establishment of drug resistance when parasites are able to survive early stochastic loss due to drift. This implies that rare importation events are more likely to lead to establishment if they occur during a high-transmission season, but that constant importation (e.g. neighbouring countries with high levels of resistance) may produce a greater risk during low-transmission periods

ThIRST: Targeted IRrigation Support Tool for sustainable coffee production

The Central Highlands of Vietnam is an important Robusta coffee growing region. However, the region is facing climate change impacts from rising temperatures and irregular rainfall, while Vietnamese coffee farmers predominantly rely on irrigation from heavily depleted aquifers. To continue productive and sustainable growth, this system requires an innovative approach to meet this hydrological challenge. Here we propose a user-friendly tool, which aims to support coffee farmers’ irrigation decisions, through the Targeted Irrigation Support Tool or ThIRST. ThIRST combines seasonal forecasts, on-farm metrics, and farmer’s expertise. The research comprises baseline ( n = 400) and endline ( n = 237) surveys of coffee farmers in Đắk Lắk and Lâm Đồng Provinces. Through the surveys, farmers’ irrigation needs and the applicability of the tool are evaluated. Despite low smartphone usage for farming advisory, the results show the tool allows coffee farmers to continually achieve water-use efficiency and adapt to climate variability. Involving farmers in the design, production and evaluation of climate services can improve the trust and uptake of agro-advisories and the way this information is communicated

Синтез обобщенного алгоритма обработки и формирования данных по отраженным сигналам от сложных целей

Introduction. The quality of input information for trajectory processing (TP) systems can be improved by increasing the measurement accuracy of radar sensors (RS). However, in such a case, radar targets acquire the characteristics of complex targets having several marks at the output of the detector. This makes it difficult to accurately assess the kinetic parameters of targets in a TP system. In this respect, the development of a generalized algorithm for processing and generating data from the reflected signals of complex targets seems a relevant research task.Aim. To investigate reasons for the formation of complex targets and, using the theory of radar image processing, to synthesize an algorithm for processing and generating data on reflected signals from a complex target.Materials and methods. The following methodological approaches were used: the theory of digital signal processing; applied theory of radar image processing; MATLAB Simulink Toolboxes for simulating radar image processing; some prerequisites for fuzzy clustering methods.Results. Following an analysis of some characteristics of complex targets and the theory of radar image processing, an generalized algorithm was synthesized for processing and generating data of reflected signals from this class of targets. The results can be used to improve the measurement accuracy of their representative point when solving the TP problem.Conclusion. Reasons for the formation of complex targets in radar technology were analyzed. Their specific features consist in the need to accurately assess a true mark. A generalized algorithm for processing and generating these signals reflected from complex targets was proposed. The results can serve as a basis for solving the TP problem.Введение. Повышение качества входной информации для системы траекторной обработки (ТО) на основе повышения точности измерений радиолокационных (РЛ) сенсоров является одним из очевидных подходов. Однако при этом РЛ-цели могут стать "сложными целями", имеющими несколько отметок на выходе обнаружителя. Это затрудняет точную оценку кинетических параметров целей в системе ТО. В статье представлены результаты синтеза обобщенного алгоритма обработки и формирования данных из отраженных сигналов сложных целей, позволяющего точно оценить кинетические параметры для решения задачи ТО.Цель работы. Краткое изучение причин формирования "сложных целей". Синтез обобщенного алгоритма обработки и формирования данных по отраженным сигналам от сложных целей на основе теории обработки РЛ-изображений.Материалы и методы. Теория цифровой обработки сигналов; прикладная теория обработки РЛ-изображений; MATLAB Simulink Toolboxes для моделирования обработки РЛ-изображений; методы нечеткой кластеризации.Результаты. На основе анализа некоторых характеристик сложных целей и теории обработки РЛ-изображений синтезирован обобщенный алгоритм обработки и формирования данных отраженных сигналов от этого класса целей, являющихся предпосылкой для точной оценки их "представительной отметки" при решении задачи ТО.Заключение. В статье проведен анализ особенностей формирования сложных целей в РЛ-технике и их особенностей при точной оценке истинной отметки; синтезирован обобщенный алгоритм обработки и формирования РЛ-сигналов, отраженных от сложных целей, являющийся основой при решении задач ТО

Transitions in diatom assemblages and pigments through dry and wet season conditions in the Red River, Hanoi (Vietnam)

Background and aims – Biomonitoring is an important tool for assessing river water quality, but is not routinely applied in tropical rivers. Marked hydrological changes can occur between wet and dry season conditions in the tropics. Thus, a prerequisite for ecological assessment is that the influence of ‘natural’ hydrological change on biota can be distinguished from variability driven by water quality parameters of interest. Here we aimed to (a) assess seasonal changes in water quality, diatoms and algal assemblages from river phytoplankton and artificial substrates through the dry-wet season transition (February–July 2018) in the Red River close to Hanoi and (b) evaluate the potential for microscopic counts and high-performance liquid chromatography (HPLC) analysis of chlorophyll and carotenoid pigments for biomonitoring in large tropical rivers.Methods – River water (phytoplankton) and biofilms grown on artificial glass substrates were sampled monthly through the dry (February–April) to wet (May–August) season transition and analysed via microscopic and HPLC techniques.Key results – All phototrophic communities shifted markedly between the dry and wet seasons. Phytoplankton concentrations were low (ca. thousands of cells/mL) and declined as the wet season progressed. The dominant phytoplankton taxa were centric diatoms (Aulacoseira granulata and Aulacoseira distans) and chlorophytes (Scenedesmus and Pediastrum spp.), with chlorophytes becoming more dominant in the wet season. Biofilm diatoms were dominated by Melosira varians, and areal densities declined in the wet season when fast-growing pioneer diatom taxa (e.g. Achnanthidium minutissimum, Planothidium lanceolatum) and non-degraded Chlorophyll a concentrations increased, suggesting active phytobenthos growth in response to scour damage. Otherwise, a-phorbins were very abundant in river seston and biofilms indicating in situ Chlorophyll a degradation which may be typical of tropical river environments. The very large range of total suspended solids (reaching > 120 mg L-1) and turbidity appears to be a key driver of photoautotrophs through control of light availability.Conclusions – Hydrological change and associated turbidity conditions exceed nutrient influences on photoautotrophs at inter-seasonal scales in this part of the Red River. Inter-seasonal differences might be a useful measure for biomonitoring to help track how changes in suspended solids, a major water quality issue in tropical rivers, interact with other variables of interest