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EN
Phu Quoc island of Kien Giang Province in Vietnam is endowed with resources for tourism development. The study explored the human resources, tourism marketing and promotion efforts of businesses towards the sustainable tourism development in Phu Quoc tourism. The authors used secondary and primary data to elicit information from respondents. Secondary data was collected from Kien Giang department of tourism, Statistical departments of Kien Giang and Phu Quoc. We administered questionnaires to 230 local residents, 150 businesses, and 530 tourists. Furthermore, interviews were conducted in Phu Quoc with local residents, businesses, tourists, local authorities’ officers, and 12 experts. The results suggest that Phu Quoc tourism sector lack quality workforce and marketing and promotion initiative is not well developed. The study proposes recommendations to stakeholders of Phu Quoc tourism sectors and more of that, the limitation and further research is suggested.
EN
Vietnam has a potential reserve of placer titanium of around 650 Mt. The reserve lays in sandy beaches of the country from Thanh Hoa to Binh Thuan province. Placer titanium mines in Vietnam are different in geological condition, the scale of production, mining method, and environmental protection solutions, etc. Some of them are operating with inappropriate mining technology; therefore, have caused environmental issues and ineffective operation. Consequently, it is essential to have criteria for selecting appropriate mining technology to approach the sustainable development for the mines. Based on categories of geology, the scale of production, mining characteristics, requirements of safety, land reclamation and environmental protection, and mining effect, authors defined the criteria and method for selecting adequate mining technology for the placer titanium mines in Vietnam which aim for better safe, effective and sustainable. The categories to select the appropriate technology for coastal titanium placers in Vietnam including 1- feasible mining scheme, 2- mining procedure, 3- requirement volume of water, 4- slope stability, 5- environmental rehabilitation and reclamation, and 6- economic effect. The result of the application for Nam Suoi Nhum placer titanium mine in Bình Thuan province shows that the most appropriate scheme of this mine is the mining technology of using hydraulic jets, pumping and hauling by pumping mud, processing by spiral screws, and discharging by mud pumping.
PL
Wietnam ma potencjalne rezerwy okruchowego tytanu w wysokości około 650 Mt. Rezerwat leży na piaszczystych plażach kraju od Thanh Hoa do prowincji Binh Thuan. Kopalnie okruchowego tytanu w Wietnamie różnią się stanem geologicznym, skalą produkcji, sposobem wydobycia, rozwiązaniami w zakresie ochrony środowiska itp. Niektóre z nich działają na niewłaściwej technologii wydobywczej, w związku z czym spowodowały problemy środowiskowe i nieefektywną eksploatację. W związku z tym niezbędne jest posiadanie kryteriów doboru odpowiedniej technologii wydobywczej do podejścia do zrównoważonego rozwoju. W oparciu o kategorie geologiczne, skalę produkcji, charakterystykę górniczą, wymagania bezpieczeństwa, rekultywacji gruntów i ochrony środowiska oraz efektu górniczego, autorzy określili kryteria i sposób doboru odpowiedniej technologii wydobycia dla stacjonujących kopalni tytanu w Wietnamie, które mają na celu zwiększenie bezpieczeństwa , efektywne i trwałe. Te kategorie obejmują 1- wykonalny schemat wydobycia, 2- procedurę wydobycia, 3- wymaganą ilość wody, 4- stateczność zboczy, 5-rekultywację środowiska oraz 6-efekt ekonomiczny. Wynik zastosowania dla kopalni okruchowego tytanu Nam Suoi Nhum w prowincji Bình Thuan pokazuje, że najbardziej odpowiednim schematem tej kopalni jest technologia wydobywcza wykorzystująca strumienie hydrauliczne, pompowanie i ciągnięcie przez pompowanie szlamu, przetwarzanie za pomocą śrub spiralnych i odprowadzanie przez pompowanie błota.
3
Content available Media Discourses of Mekong Dams: A Thematic Analysis
EN
Economic and political stability in Southeast Asia has led to a surge in Mekong dam development and construction in the 2010s. But, not only has the logistics of dam construction changed dramatically in the 35 years since Mekong hydroelectric development began; the public discourse surrounding hydroelectric development in the region has also expanded and diversified. The Mekong, while still seen by some throughout the region as a source of untapped economic opportunity, is also a source of growing concern for states who are losing control of the dams’ ecological impact. Both of these visions of the river are framed in the public imagination of various states by their respective media's chosen depiction of the issue of dam development. Through an examination of the discourse surrounding Mekong hydro development in the four Mekong River Commission (MRC) states, this paper explores the divergent interests of states currently engaged in a complex water diplomacy. Themes drawn from the English-language press coverage in Laos, Thailand, Cambodia, and Vietnam are compared to determine how the unique geographic and economic positioning of each state shapes their media's depiction of Mekong dam development. Shared concerns about environmental damage, MRC weakness, and economic futures are also explored.
PL
Ekonomiczna i polityczna stabilizacja w południowo-wschodniej Azji doprowadziła po 2010 r. do podjęcia decyzji o budowie zapór na rzece Mekong. Od czasu, gdy 35 lat temu rozpoczął się rozwój energetyki wodnej na rzece Mekong wiele się zmieniło i to nie tylko od strony logistycznej, także dyskusja publiczna odnosząca się do przyszłości hydroenergetyki w regionie uległa rozszerzeniu. Rzeka nadal postrzegana jest przez wielu jako potencjalne źródło ekonomicznego wzrostu, zarazem jest przedmiotem rosnących obaw dla krajów, które wydają się nie być w stanie utrzymać pod kontrolą ekologicznych konsekwencji budowy zapór. Oba podejścia trafiają do obiegu publicznego w poszczególnych krajach dzięki doniesieniom medialnym. W niniejszym artykule dokonano przeglądu dyskursu wokół rozwoju hydroenergetyki na rzece Mekong w czterech krajach należących do Komisji ds. rzeki Mekong (Mekong River Commission. MRC), ukazano rozbieżności w preferencjach poszczególnych krajów, zaangażowanych w skomplikowaną dyplomacje wodną. Porównano treści publikowane w anglojęzycznej w Laosie, w Tajlandii, Kambodży i Wietnamie, w celu ustalenia, w jaki sposób unikalne położenie geograficzne i gospodarcze każdego państwa kształtuje obraz ich mediów w kontekście budowy kolejnych zapór na rzece Mekong. Omówiono również wspólne obawy dotyczące szkód wyrządzonych środowisku naturalnemu, słabości komisji MRC i konsekwencji tego stanu dla przyszłości ekonomicznej regionu.
EN
Having enjoyed an economic upsurge in recent years, Vietnam is now recording increased demand for electrical energy. Its production, for the most part, relies on the coal mining industry, thus resulting in a strong upward trend in mining volumes. Being geologically complex, Vietnamese mines are characterised by a complicated structure of their headings. The local ventilation systems are also affected by there being very few automatic dams and an by increases in airflows delivered to the mine. For this reason, in order to analyse airflows and maintain the proper control of ventilation systems, computer software is required. The article offers a comparison of computer programs – Kazemaru, VentGraph and VentSim – as employed for use in Vietnamese mines. The assessment covered the manner in which these programs are used and how their output data are presented, as well as their range of applications in the conditions of Vietnamese coal mines.
EN
Vietnam has the 13th largest hard coal reserves globally, with the reserves totaling 2.22 billion tonnes, and estimated resources of 4.07 billion tonnes. Coal use is playing an increasing role in the energy mix and according to current planning, this role is to increase further. In parallel with the development of the Vietnamese coal sector, underground mining also underwent many stages of improvements, especially in the last two decades. This paper analyzes the achievement and the state of the mining technology applied into the underground mining by the Vietnam National Coal - Mineral Industries Holding Corporation Ltd. (VINACOMIN) during 20 year period and proposes the recommendations for the sustainable development of Vietnam underground mining.
EN
The coal reserves in protection pillar of roadways are expected to be left in the mining process in underground mines in Quangninh coal basin which is relatively large (about 16% of the total reserves). If it can be exploited, it will help to save non-renewable coal resources, reduce the cost of preparing roadway meters, extend the mine life and increase the efficiency of construction investment. In the world, in order to reduce coal loss in protection pillar of roadways, mining technology to exploit and use artificial protection pillars are quite popular. Accordingly, in order to simultaneously exploit coal in the protection pillar and maintain the transport roadway as a ventilation roadway for the longwall in below level, the post-mining coal pillar will be replaced by artificial pillars formed from the stone backfill cribs, columns, metal cribs, chemical materials or low-grade concrete mortar mixes formed from fly ash, bottom ash of thermal power plants, combined crushed waste rock and a cement additive,... This paper will evaluate the possibility and propose a number of mining technological scheme as well as the type of construction materials suitable for artificial columns.
EN
Underground coal mining in Vietnam plays an important role to not only the sustainable coal industry but also the energy and social security in this country. Although the Vietnam coal industry has produced 35–45 million tonnes of raw coal per annum in past ten years, a great volume of coal resources remains distributed in complex geo-mining conditions and mostly unmined. This paper presents a brief review of the current and potential technologies for cutting coal and controlling roof in Vietnam underground coal mines. From the review, it is concluded that there is an urgent demand on improvement of current technologies as well as on investigation for effective application of more advanced mining methods into the industry, especially for deep mining at Red River Delta—the largest coal basin in Vietnam.
EN
The contaminated waste is a by-product generated during coal mining process. This type of products may contain more or less 20% of clean coal, thus their ash content may vary in a wide range of 60 to 80%. This waste normally is stockpiled separately at “temporary disposal dumps” as they would not be regarded as waste in the full meaning, however, it is very sensitive for the miners who attempt to process such a waste. Based on the results of the coal characteristics survey at some surface coal mines of Vietnam, the studying authors have collected a large quantity of representative samples, such as Ha Tu, Nui Beo, Tay Khe Sim, Ha Rang mines and have carried out a number of experiments using low cost and highly efficient separating equipments. These are semi-industrial movable screen jig, fluidization separator, some samples of -0.5 mm size using flotation method. Products of processing include clean coal, which has ash content obtain quality standard of Viet Nam (clean coal is consumed easily) and tailings have ash content over 80%, which can waste. The study results showed that the application of the new machines could allow significant recovery of clean coal from the contaminated waste. This may significantly contributes in reduction of environmental pollution while ensuring the production viability and economic efficiency for the miners.
EN
Apatite ores type III of Lao Cai area, Vietnam is a class of weathered sileceous apatite ores, which may have most variable composition and primary slime content according to the weathering level and location. The three operating flotation plants use similar single-stage grinding circuits to process the highly weathered sileceous apatite ores and to achieve the concentrate grade requirement of 31% P2O5 with the aimed average recovery of about 70%. Single stage grinding circuits have worked well in the past as the designed criteria were achieved, however, mine production has increased sharply and deeper ores are being mined recently, so that the material composition of the run of mine ores have become more complicated and are the ores become more difficult to be floated. As a result, processing criteria of these plants become critically unstable and low. The study is to investigate the suitabity of two-stage grinding circuits for Lao Cai apatite ore type III. The report presents the results of the study on middlings regrinding of hard floatable apatite samples of Bac Nhac Son flotation plant, where high loss of valuable apatite has occured due to low grinding performance. Research results show that regrinding of all middlings to the fineness of 75% -0.04mm not only improves recovery but also help to stabilize technological operations and their processing criteria. The final concentrate grade of more than 31% P2O5, tailings content of less than 5% P2O5 and recovery of over 70% were achieved.
EN
Single phase earth-fault in MV grids usually causes overvoltage that harm to human being and electric equipments. In 6kV mining grids of Vietnam, earth fault which is majority incident accounts 55% to 73% of the total faults. When earth fault occurs many grids’ eco-technical parameters will be affected. Moreover, the overvoltage and earthing current can lead to serious electric shock accidents caused mainly by stepping-overvoltage or touching-overvoltage. One of earthing relays requirements is to trip in minimum time duration in order to reduce the magnitude of earthing currents and overvoltage. Base on the simulation in Matlab, the paper suggests a prior connection diagram that allows an auto earthing-connection for improving the better performance of relays. The utilization of the diagram will help to decrease the tripping time of relays, reduce the amplitude of internal overvoltage as well as enhance the safety for human being in case of earthing incidents.
EN
Against the serious consequences of climate change, a new growth model has been established. The green growth or low carbon growth focuses on the efficient use of natural resources, it also enhances the use of renewable energy and environmentally-friendly technologies. Therefore, the green growth is now a trend with new global rules being shaped. This paper presents the trend of Southeast Asian countries on green growth in mineral mining, one of the economic growth activities which has a negative impact on the environment so that draw lessons for Viet Nam.
EN
With many types of trucks and shovels for hauling large volume of waste rocks to the dump sites and coal to the storages, the truck – shovel dispatching in Cao Son open pit coal mine is the operation which needs to be improved. At present, the combination between trucks and shovel is usually assigned at the beginning of shift and adjusted during the operation at the mine. The GPS tracking system are integrated into each truck to monitor the position in real time, but applying this information to find the best destination to send the truck to satisfy the production requirements and to minimize truck operating costs is still not used. This paper presents the estimation of the information system, data, the remaining problems of truck – shovel dispatching system, from that proposes the application of available information technology for increasing the efficiency of this activities at the mine.
EN
The principal object of this study is blast-induced ground vibration (PPV), which is one of the dangerous side effects of blasting operations in an open-pit mine. In this study, nine artificial neural networks (ANN) models were developed to predict blast-induced PPV in Nui Beo open-pit coal mine, Vietnam. Multiple linear regression and the United States Bureau of Mines (USBM) empirical techniques are also conducted to compare with nine developed ANN models. 136 blasting operations were recorded in many years used for this study with 85% of the whole datasets (116 blasting events) was used for training and the rest 15% of the datasets (20 blasting events) for testing. Root Mean Square Error (RMSE), Determination Coefficient (R2), and Mean Absolute Error (MAE) are used to compare and evaluate the performance of the models. The results revealed that ANN technique is more superior to other techniques for estimating blast-induced PPV. Of the nine developed ANN models, the ANN 7-10-8-5-1 model with three hidden layers (ten neurons in the first hidden layer, eight neurons in the second layers, and five neurons in the third hidden layer) provides the most outstanding performance with an RMSE of 1.061, R2 of 0.980, and MAE of 0.717 on testing datasets. Based on the obtained results, ANN technique should be applied in preliminary engineering for estimating blast-induced PPV in open-pit mine.
EN
In dimension stone quarry exploitations such as the marble quarry, a literature review of the existing numerical modelling techniques has been carried out. According to Distinct Element Method, discontinuities have been treated as boundary conditions between blocks and, consequently, an accurate knowledge of joint distribution and orientation was required. The result of analyzing data and simulating in the fracture rock environment, which is applied to a mining condition of the dimensional stone quarries. The research we introduce in the output capacity of the dimension stone quarry from the computer simulations to generate the fracture network in 3D with an aim of evaluating the size of the blocks. The results of numerical models have been used to optimize some of the technical parameters for dimensional stone extraction and ensuring stable bench in the mining operation.
EN
Methane gas is one of the most serious dangers of underground coal mining as its buildup can lead to methane gas explosion. In QuangNinh province- Vietnam, several coal mines such as TrangKhe II-III coal mine, Khe Cham coal mine, especially MaoKhe mine that have high methane content. At the MaoKhe coal mine,experimental data showed thatthe concentration of methane in coal seams at different depths were not similar.In order to ensure safety, this report has been undertaken to determine a pattern of changing methane contents of coal seams at different exploitation depths in MaoKhe underground coal mine.
EN
The research about wastewater treatment in laboratory scale of Trang Bach coal mine in Vietnam was carried out in the year of 2016. We concluded the content of chemical compound that needed to treat the pH, Fe, Mn component and Turbidity & Suspended Solids (TSS) in the wastewater to meet the requirement of the Technical Regulation for Industrial Water of Vietnam. In this article, we suppose to compare the Vietnam and Poland regulations for industrial wastewater based on the result of our research about Trang Bach coal mine wastewater treatment before and then assess the potential to exchange the scientific works about wastewater treatment between Vietnam and Poland.
EN
The article in individual chapters discuss domestic coal resources in Poland and Vietnam, types of coal occurrence in both countries, the processing status and main domestic mining companies. The last part will be a comparison of mining prospects and plans for the development of coal mining in both countries and a summary of positive practices in both countries.
EN
The article discusses the possibility of improving the microclimate in underground hard coal mines in Vietnam. Vietnamese underground mines are shallow mines which extract coal deposits accumulated up to 500 m below ground. According to the current Vietnamese laws, coal deposits can be mined if air temperature does not exceed 30oC, although this rule is not always observed, especially during summer. This article analyses the impact of air parameters on the climatic conditions in headings and the use of the air temperature reduction method in selected underground mines in Vietnam.
EN
The article presents the choice of a Polish powered roof support from FAMUR Group for the conditions of one of the hard coal mines in Vietnam. In the analytical calculations, the strength and structural parameters of the rock mass from the Vang Danh mine region were adopted. The longwall face is 93 m long and the thickness of the coal layer is equal 3 m. For the needs of the choice of support, the load of the longwall face determined and the capacity of the powered roof support were determined. On the basis of the permissible roof deflection method, the condition of excavation maintenance was characterized. In the calculations, it was assumed that the condition of using a powered roof support type FAZOS-15/31-POz, except in addition to complying of the working range and permissible value of longwall face inclination, is to ensure proper roof maintenance conditions, which are determined by the index of load capacity of the roof „g”.
EN
In underground mine ventilation, there are many causes affecting the efficiency of mine ventilation, even affecting mine safety. In order to have an effective mine ventilation system, the research and evaluation of mine ventilation, in order to get timely solutions to improve the efficiency of mine ventilation, is essential and must be done. regularly. Thanh Cong - Cao Thang coal mine area of Hon Gai Coal Company, Quang Ninh region, Vietnam is a mine exploited underground. The nature of this mine is the consolidation (connecting) of Thanh Cong areas and CaoThang areas in the period of 2016. After consolidation into Thanh Cong - Cao Thang mine, many factors in the mine ventilation system of The mine site is altered and affects the efficiency of mine ventilation. This article has analyzed and evaluated the current status of Thanh Cong - Cao Thang Area Ventilation System to help research and select appropriate solutions to promptly improve the efficiency of mine ventilation and ensure security, ensure a safe environment and reduce the cost of mine ventilation.
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