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EN
With its position as the capital, Hanoi is the political center as well as the second largest economic center of the country. Therefore, the city is always allocated a large budget in construction investment to create material facilities for political tasks and economic and social development. During the implementation of construction projects, a number of difficulties and limitations have appeared. In which, projects are delayed in construction and disbursement, reducing investment efficiency and not meeting the expectations of the government and people. From this fact, the authors have conducted a study to evaluate the causes affecting the time schedule of construction projects in Hanoi. The method F-APH (Fuzzy Analytic Hierarchy Process) was used to analyze data objectively and accurately about the causes affecting the time schedule. From there, these causes are classified into groups of subjective causes (from within the project) and groups of objective causes (from outside the project). The results show that subjective causes, originating from project participants, have a stronger influence than objective causes. A number of specific proposals to the actors involved in construction projects are made to eliminate or limit the impact of the causes of construction progress.
EN
This paper analyzes the achievement and the failures of applying the mechanized mining method in underground coal mines by the Vietnam National Coal e Mineral Industries Holding Corporation Ltd. (VINACOMIN) for 15 years (from 2005 to 2020). It also proposes the recommendations for developing mechanized mining in order to improve coal production, productivity and safety management for the sustainable development of Vietnam's underground coal mining in the period 2021-2025.
EN
Saltwater intrusion in the rapidly developing city of Da Nang in central Vietnam is currently causing various water-related challenges, including inadequate water supply and water pollution. An integrated SWAT-MODFLOW numerical model was used to investigate the origin and mechanism of saltwater in Holocene and Pleistocene aquifers. Geophysical and isotopic approaches were used to validate the SEAWAT model applied for simulating saltwater intrusion. The results suggest that the ebb and flow of tides, as well as water levels in rivers primarily impact coastal aquifers. However, effective water resource planning and management, along with maintaining the natural recharge of fresh water from local rain during the rainy season, could enable the rational and efficient utilization of groundwater, reducing saltwater intrusion in many areas. During the dry season, groundwater is recharged from higher altitude areas. The current saltwater intrusion mainly occurs along the rivers up to the hydraulic dam. Simulated models, using scenarios of stop abstracting groundwater, but changing to the use of surface water for drinking water, show that the area of saline water shrinks quickly after 30 years, reducing from 59.6 km2 to 39.5 km2 and from 40.2 km2 to 28.6 km2 in the Holocene and Pleistocene, respectively.
4
Content available Sustainable Industrial Development in Vietnam
EN
Vietnam is one of the countries with the highest industrial growth rate in the world. However, growing in the industry is based on the width factor and labour - intensive industries and assembly. The goal set out to 2030 is to turn Vietnam into a Middle-Income Country (MIC) with a modern industry that poses many challenges, requiring the industry to need stronger restructuring to improve competitiveness. competition and deeper participation in global value chains. From the analysis of the current situation of industrial development in Vietnam, the article identifies the limitations in the sustainable development of Vietnam's industry and gives orientations and solutions to promote the sustainable development of Vietnam's industry in the context of Industrial Revolution 4.0 and the digital economy.
EN
The Ta Phoi beneficiation plant is one of the main copper beneficiation plants in Vietnam. The plant has been put in operation since 2019 and annually process more than one million tons of ROM copper ore to collect 32 thousand tons of copper concentrate of 23% Cu. In the first years of operation the plant’s metallurgical performance has not been consistent and not been as good as in design. The most important task at the company in this day is to improve and stabilize this performance with a target to obtain the copper concentrate of 23% Cu and recovery of over 91.5%. This report presents some research results to increase the recovery and quality of the copper concentrate at Ta Phoi beneficiation plant. As the results, some technological solutions have been proposed concerning the optimization of the reagent regime as well as of flotation flowsheet. Some of these solutions have been tested directly in the plant production line and have the perspective to apply.
EN
In recent years, Quang Ninh coal mines are continually expanding on size and depth, the total length of the roadway each year amounts about ten thousands meters in order to reach new production zones. The length of new roadways is usually longer, leading to increase to the airflow demand. Ventilation is one of the main factors effecting driving progress of the roadway. The estimation of airflow requirements is usually based on the minimum amount of airflow required at the heading during driving roadways or at the working face, in other words, when the ventilation ductwork is at its maximum length. Therefore, determination of maximum ventilation length of ductwork has been undertaken. This results allow the selection of a reasonable fan to meet the ventilation requirements when driving the roadway. Also, this value is an important parameter for designing auxiliary ventilation system that operates more efficiently on a lower cost.
EN
This paper presents the results of applying the unsupervised learning method (K-means clustering) on the gravity anomaly field in the central region of Vietnam to separate the research area into different clusters, which are homologous in physical properties. In order to achieve the optimal results, the input parameter plays an important role. In this paper, we chose 04 input attributes including the gravity anomalous field attribute, the horizontal gradient attribute, the variance attribute, and the tracing coefficient of the gravity anomalous axis. The obtained results have shown that the research area could be divided into 7 clusters, 9 clusters, 11 clusters, and 13 clusters with close characteristics of the physical properties of the gravity field. The research results show that the Southwest, the Center, and the South of the study area have complex changing physical properties, this result reflects the complicated tectonic activities in these areas with the presence of crumpled and fractured rock layers in different directions and these locations are the potential places to form endogenous mineral deposits of magma origin. The Northwest, the North, and the East parts of the research area witness negligible changes in the field's physical properties, reflecting the stability of the soil and rock layers in this area, with the direction of extending structure from the Northwest to the Southeast. The clustering results according to the K-means unsupervised learning algorithm in central Vietnam initially increase the reliability of the decisions of geologists and geophysicists in interpreting the geological structure and evaluating the origin of deep-hidden mineral deposits in the area.
EN
Nowadays, there are many underground coal mines in Quang Ninh, Vietnam have been exploiting coal seams below the mine waste dump such as Khe Cham II, Mong Duong, Mao Khe, and Ha Lam… Coal Company. Many mine waste dumps have reached the height of dumping from 400m, especially up to over 400m. The rock mass pressure due to the weight of the rock mass in the mine waste dump is considered an artificial pressure formed from the process of dumping soil and rock, it will be part of the pressure acting on the furnace lines located under the mine waste dump. The paper presents the current status of the mine waste dump and the coal seams that have been and will be exploited located below the mining waste dump in Cam Pha Quang Ninh and based on the actual conditions of the Bang Nau, Khe Cham II coal mine waste dump. The studies used the 2D FEM RS2 program to create simulation models with the mine waste dump to study the primary stress distribution in the rock mass. The objective of this study is to highlight the influence of the relationship location of tunnels below with the inclined coal/rock mass layer on the rock support behavior of the underground tunnels in the Quang Ninh coal area. The simulation results will help the consulting and construction companies to calculate the rock pressure acting on the tunnels located under the mining waste dump.
EN
The coal mining industry in Quang Ninh province is primarily focused on serving thermal power plants which has resulted in a substantial amount of waste rock and ash. This way has not only narrowed the used land but also had a negative impact on the environment. However, the economic development plan for the province until 2030 emphasizes the development of a greener economy. Therefore, balancing between economic growth and environmental protection is one of the significant challenges of this province. To solve the problem of waste rock and ash dumps, some methods have been proposed. It tends to use waste materials for backfilling the underground mines, this can help to minimize the bad impact on the environment. Additionally, Another solution is to handle the waste in abandoned mining areas, or use them as construction materials. These ways are expected to partially reduce the bad effects of waste rock and ash dumps on the environment. In the world, there are many studies on filling using waste rock and fly ash, but in Vietnam this issue is quite new. In order to turn waste rock and fly ash into filling materials, the article researches on a laboratory scale, the ability of transportation in hydraulic pipelines, level of the water separation and shrinkage of mixtures of rock and fly ash in the Mong Duong – Coc Sau area with the different proportions. The results of the experiments show that the area has appropriate mixing ratio as 70–73% of waste rock and 30–27% of fly ash, this ratio satisfies the transportation conditions in the pipeline and the shrinkage rate of 8, 8–12.3%. The indicators in experiments show that it is able to take waste rock into mined underground area to fill, which prevents displacement of strata from mining, protects the underground water flow, and also reduces negative impact of waste rock on environment.
EN
Ngoc Luong thermal mineral water at Vo Am ecotoursim, Ngoc Luong commnune, Yen Thuy district, Hoa Binh province, northern Vietnam. The thermal mineral water source is at karstic-fractured limstones of Dong Giao Formation aged Anisi. Methods used in this study conists of basic field survey of hydrogeology, resistivity, borehole drilling, pumping tests, and thermal mineral water sample analysis. The thermal mineral water is classified as radon-radium, low mineralised thermal mineral water. The water source is originally related to the deep Moc Chau-Tam Diep Fault directing northwest-southeastward. Its exploration reserve is estimated at 1,497 m3/d with good quality, sastifying all national criterals for the use of domestic supply, bathing, and medical treatment. This is one of ten rare thermal-mineral water sources in Vietnam, containing radon and radium. It is thefore necessary to have good management to ensure the thermal-mineral water to be effectively exploited, used, and protected.
EN
Females in the industry nowadays have been offered many opportunities to develop their careers. However, the chances are not the same in different areas or sectors. This study investigated the perceptions and understanding of gender-related issues in the mining sector among potential young workers and industry experts in Vietnam. The study employs Oxfam's Gender Impact Assessment Guidelines for extractive industries and the Convention on the Elimination of All Forms of Discrimination Against Women - CEDAW's Women's Economic and Social Rights Framework to assess gender-related issues in the mining sector. A survey of 207 students in Hanoi was conducted, besides focus group discussions and in-depth interviews with gender and mining experts. Findings reveal significant differences in knowledge and awareness of gender issues between students, emphasizing the need to integrate gender knowledge into specialized fields such as mining. In addition, professionals working solely in the mining sector demonstrated a lack of sensitivity to gender issues. Consequently, the study recommends capacity building, seminars, and exchanges to help mining professionals incorporate a gender perspective into their activities. Current policies exhibit gender neutrality, indirectly excluding women's participation and compromising men's safety in the mining sector. The study proposes policy recommendations for enhancing the protection of workers in the mining industry and promoting gender equality. These include incorporating gender perspectives into relevant laws, raising awareness of gender issues among policymakers and professionals, and increasing the mining sector's presence in the media to encourage youth to pursue careers in this field.
EN
The increasing depth of extraction and the degree of mechanization leading to the risk of workers working in poor microclimate conditions has become one of the major safety issues in coal mines. During the survey of the current microclimate in Mongduong coal mine, it showed that the temperature of the mechanized longwall exceeded the permissible regulations (t°≤ 30°C), the air humidity is about 95–100%. The reason for the increase of air temperature in longwall is due to geothermal, heat radiated from the longwall equipment and the inlet wind high temperature. To improve the thermal environment in the mechanized longwall area, Vietnam's coal mines open use ventilation, but the efficiency is not high. Therefore, the paper evaluated the influence of airflow on the temperature of the longwall, 7 models with different air flow velocities and 3 models with inlet air temperature have been created in ICM-CFD and simulated by Ansys CFX software. The environment temperature of each model was evaluated by analyzing the average temperature of the roadway section, the cross-section distribution of the roadway temperature and the velocity streamline of the whole roadway. As a result, the air flow rate increases leading to the air temperature in the longwall decreases, however the wind speed is limited. The inlet temperature of the gas stream is an important factor that affects the thermal environment in the longwall. The results of the article are the basis for making solutions to improve the thermal environment suitable for high-temperature longwall.
EN
The west coast of Camau (Southeast Vietnam) connects two semi-enclosed East Sea and Thailand Bays, allowing water exchange between them. Despite its importance to the oceanographic evolution of the region, it has still been poorly studied. Therefore, Subbottom profilers are used across shallow sea waters with some applications, such as sea-level studies, sedimentation process and geomorphology. In the whole survey area, 6 high-resolution shallow seismic measurements have been performed with a total length of 60.6 km, and all have recorded good reflected signals in the range 20–70 ms. In this section, physical characteristics and nature of petrology in the survey environment are quite uniformly shown. The topography of the seabed in the survey area tends to be gradually shallower from west to east, and is relatively flat. Particularly, on the cross section of the T1 line, it is visible that the first section of the line has a rather steep and deep terrain, which may be the slope of the continental shelf in the survey area. Wedge-shaped, oblique, corrugated and transverse structures all appear on the cross-sections. In the survey area, the shallow geological structure in the Holocene sediments is divided into 4 layers, and the structural boundary between the Holocene and Pleistocene sediments at the depth of 25–35 m is observed. In addition, geological faults are also detected on geological sections from seismic sections. For instance, at the section of T6 line, two faults were detected at the beginning of the line. The displacement amplitude of these faults ranges between 1.5–4 m. This new dataset will contribute to future comprehension of the geologic and oceanographic evolution.
EN
Tourism is one of the most important factors in economic growth in Vietnam. However, it requires the balance between economics, social-cultures, and ecology because of their big impacts. In this paper, we propose a platform with mobile and web-based applications that can support smart and sustainable tourism in Vietnam for both local governments and visitors. The mobile application allows visitors to access location-based services to explore the visiting area, such as finding nearby natural attractions, as well as information to minimize the negative effects of tourism on the environment and the local community. It also enables users to report negative impacts to local government. The web application allows local authorities to monitor the status and trends of the habitant, natural environment, tourism infrastructure and activities in the area. The system uses geographic information systems (GIS) and remote sensing techniques to collect, analye and visualize various indicators of sustainability. The platform is developed with open-source technologies such as NodeJS, PostgreSQL, and Flutter. The paper demonstrates the feasibility and usefulness of the proposed platform through case studies in Hoa Binh and BacKan, two provinces have many attractive natural sites.
EN
Industrial symbiosis associated with the eco-industrial parks is the cooperative activities between businesses to optimize using of inputs and outputs such as raw materials, energy, water, waste materials, etc. in the orperation of businesses. In the industrial symbiosis model, the overall benefits of the symbiosis activities are more than the ones when working individually. Applying the model could help to reduce the demand of raw materials and increase the waste that be treated – an important part of the circular economy model. The coal mining industry includes many different stages from exploration, exploitation, processing, and trading. Each stage could be performed by different businesses which could corporate with each other. Besides the contributions to the socio-economic development, the industry also emits lots of waste into the environment to cause environmental pollution that needs to be treated. The paper summarizes the theoretical basis of the industrial symbiosis, the circular economy and clarifies the relationship between the industrial symbiosis, the circular economy and the sustainable development goals. From analyzing some typical situations of industrial symbiosis activities in Vietnamese coal mining industry; analyzing some characteristics and potential application of industrial symbiosis in the industry, the paper proposes the model of industrial symbiosis for Vietnamese coal mining industry. The paper also proposes some solutions to promote symbiotic activities in the industry.
EN
The primary function of the river dike system is to safeguard lives and property from flood hazards. However, due to aging infrastructure and various geological or anthropogenic factors, certain vulnerable sections of the dike system can emerge as the water level in the river increases. Flood maps are one tool that presents vital information for authorities and residents in the flood risk mitigation. This study's primary goal is to provide a flood map under the dike break condition using the estimated fracture size parameters from a geo-radar survey and the MIKE FLOOD model. This approach addresses the observed research gap by utilizing a survey database instead of relying on empirical models which are capable to produce the conservative estimates of the dike breach outflow. A case study is conducted on the Hoang Long River dike system in Ninh Binh Province, Vietnam.
EN
The Song Hien Rift basin, located in northeast Vietnam, has been identified as an important region for gold deposits, including the Pac Lang deposit. Several methods like petrographic observations, elemental analyses, and geochemical elements and vertical zoning models of primary halo have been used to describe geological characteristic of this deposit. The investigation focused on examining the geological events that occurred both before and after the formation of the ore. The use of ICP-MS analysis and element concentration contrast enabled an effective assessment of the relative degrees of denudation that occurred at the Pac Lang deposit. The findings of this study were consistent with prior research on ore deposit geology, geochemical primary-halo, and examination of geochemical indicator zoning patterns for gold ore bodies. The study's application of singularity analysis for evaluating the degree of denudation provides important geological information that can aid in data interpretation. The results of the study can also have significant reference value in furthering our understanding of the post-ore deformation of deposits and in the investigation of unknown orebodies in northeast Vietnam. There indicate that, the research's findings suggest that the use of singularity analysis to evaluate the degree of denudation is a valuable tool for exploring potential gold deposits and enhancing our knowledge of gold deposit geology in northeast Vietnam. Overall, this study contributes to the existing body of knowledge on gold deposits in the Song Hien Rift basin and can serve as a useful reference for future research in the area.
EN
Binh Duong is the leading industry development province of Vietnam. In particular, quarries in Di An, Phu Giao and Tan Dong Hiep districts have contributed significantly to the demand for construction and transportation in the locality and vicinity. The quarries in Binh Duong province are exploited by the open-pit mining method. The mining depth is from 100m to 150 m. The mine surface area is hundreds of hectares. At the end of the quarries will leave huge pits. The current regulations of Vietnam on mine closure are mainly aimed at ensuring the stability of the physical and chemical factors of the mine, while the land use after the mine closure is permanent. Binh Duong province has a rapid urbanization rate, the use of land after mining here is very important and has a significant influence on the sustainable development of the region. Depending on the occupied area of the mine or mine cluster, there are many options to close the mine after mining based on the required technical, economic, social and environmental criteria. The paper uses fuzzy multi-attribute decision model to calculate the optimal solution selection. The selected option is to use the mine lake for tourism, entertainment and water storage at Nui Nho mine, Di An city, Binh Duong province with the highest total score of economic, social and environmental criteria.
EN
In underground coal mining, the stability of roadways and gob-side entry depends on the coal pillar width. An unreasonable width of the coal pillar will cause the roadway to be in a dangerous zone of influence of the abutment pressure, leading to severe roadway deformation. This paper studies the fracture mechanism of the hard main roof and reasonable coal pillar width to protect the stability of gob-side entry driving. The research results show that when mining a coal seam under a hard main roof, the console of the main roof on the edge of the coal seam has the form of hinge structure. The great load of the roof layers and the rotation of the console are the main causes leading to the variation of the stress field in the coal seam. According to the development law of the stress field, after the main roof completes the collapse process, the peak of the maximum stress will move deep into the solid coal seam, and on the edge of the coal seam it will form a low-stress zone. Research results from the case of Seam #11 of Khe Cham coal mine, Vietnam show that the gob-side entry will be well stabilized when the narrow coal pillar between it and the boundary of the gob is 4–5 m.
EN
The article presents the facies and environment of the Upper Oligocene sediments in the area of block 09-2/10 based on the analysis of seismic facies and well data of the neighboring areas. The results of the interpretation of seismic data indicate that the upper Oligocene sediments are limited by the top C, top D seismic reflectors. The environment is formed from lagoons, lakes to deep lakes. Seismological facies analysis identified 03 facies including seismic facies with medium to poor reflection amplitude, medium continuous, low frequency reflecting the lacustrine sediments (80%) in most of the lake center. Strong reflective seismic facies, sigmoidal clinoforms reflect the lakeside sediments (15%) distributed in the lakeside shelf. The seismic facies with average and continuous amplitude poorly reflect alluvial sediments (5%) in the Northwest region. The direction of sediment transport is mainly from the Northwest and Southwest in the area. The sandstone sequences are distributed on the slopes of the lake and the lake bottom, which is potential reservoir.
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