Tạp chí Khoa học và Công nghệ - Đại học Đà Nẵng

Affecting analysis of business risk factors to profitability of construction companies in Vietnam

Tran Thi Hoai Thuong — 2024-11-30

Risk management in the construction sector in Vietnam has received much research attention in recent years. However, in-depth studies on the impact of business risk factors on the financial performance of domestic construction enterprises are still limited. This study focuses on measuring and analyzing the impact of business risk factors on the profitability of construction enterprises in Vietnam in recent years. Multivariate linear regression method is used to measure the impact of business risk factors based on the financial statement data set of 60 medium and large construction enterprises listed on the Vietnamese stock market from 2018 to 2023. The research results show that enterprises with better risk management capabilities often achieve higher financial performance. The study proposes a number of solutions to improve profitability through multidimensional risk identification and management, helping businesses develop effective response strategies and thereby optimize profits.

Analysing the urban morphology of Hoi An ancient city, Quang Nam province in sustainable coastal tourism, vision to 2045

Le Thi Kim Anh — 2024-11-30

Hoi An ancient city being favorable location played an important role as a commercial center during the past to nowadays, especially Faifo commercial port in 14th century. Hoi An is a huge potential tousism in unique heritage mixing diverse nature. However, expanding Hoi An urban serving tourism development has negatively affected the diverse Hoi An's ecosystem. Meanwhile, Hoi An's urban planning solutions didn't get the effective results, because of less analyzing urban morphology trends which find out transformation of land use's shape as well as population density. From that, the following article will: (i) analyze the urban development context of Hoi An city, (ii) analyze the urban spatial morphology and (iii) propose solutions to apply TDR (Transfer Developmnt of Right) model, that considered as useful method for sustainable coastal and river urban planning in Hoi An, as well as enhances the ability coping to climate change and extreme weather.

Architectural heritage value with indigenous culture in Binh Duong (in case of the architecture of traditional houses and communal house)

Tran Dinh Hieu — 2024-11-30

Binh Duong territory has a long history marked typically by an architectural culture of Vietnamese, French, Chinese style. This land has an open village structure that was established through royal bibliographies and directories in the early stages of Nguyen Dynasty. People of Southeast region have an open spirit and cultural exchanges with Chinese; Therefore, they have created their own cultural and architectural character through the way of their treating of Gods in architecture of communal houses. At the end of 16th, 17th and middle 18th centuries, because of dissatisfaction of some Vietnamese population from Central provinces with Trinh Nguyen Lord war, migrating of valet members of Nguyen Lord to Southern territory and with French colonial period formed architectural culture system of traditional architecture and colony style. The contents analyze, evaluate cultural and architectural values of typical communal houses and traditional houses through cultural and architectural characteristics of typical heritage buildings.

Architectural morphology study towards sustainable design solutions (case study of Ha Noi children's palace design)

Doan Minh Khoi — 2024-11-30

Researching building architectural morphology is one of the important tasks of architectural design, not only referring to formal design but also related to factors affecting form such as function organization, technical structure, technology implementation. Sustainable design is not only a current trend but also a goal that designs should aim for in order to minimize environmental impacts, save energy as well as to preserve and promote cultural values. This article studies the dialectical relationship between architectural form and sustainable design solutions. The methods used in this paper include systematic and logical analysis methods, diagramming methods, and empirical research methods through the case study of the design of the Hanoi Children's Palace – a construction that was recently completed in July 2024.

Assessment of air pollutant emissions from rice straw open burning in Hoa Vang district, Da Nang city, Vietnam

Nhu-Thuc Phan — 2024-11-30

This study inventoried the air pollutants from rice straw open burning (RSOB) in Hoa Vang district, Da Nang city, Vietnam. The rice straw in Hoa Vang district tended to decrease due to the shrinking rice cultivation area, of which 73% was reused in mushroom growing, livestock feeding, composting..., the remaining 27% was not reused and burned. The amount of rice straw burned in 2019 and 2023 was 25544 and 23377 tons, respectively. In 2023 the emissions of CO₂, CO, PM₁₀, PM_2.5, SO₂ and NO₂ from RSOB were 27138, 1720, 509, 233, 25.9 and 11.4 tons/year, respectively. Burning conditions affected the air pollutant emissions from RSOB. At 5m from the burning site, the air pollutants were higher than the permissible standards, whereas at 200m from the burning site, the air pollutants decreased to the background concentration. These results are useful for both local and national environment managers in controlling air quality.

Evaluate the feasibility of implementing activitysim activity-based model for Vietnamese municipalities in term of the available input data sources

Cao Thi Xuan My — 2024-11-30

Activity-based modeling (ABM) has emerged as a promising approach in urban travel demand forecasting, addressing the limitations of traditional models that have dominated the field for over 50 years. ABM offers a powerful framework for simulating traffic at the city scale, enabling a deeper understanding of the complex behavior of urban transportation systems under various scenarios. This paper concisely overviews recent advancements and challenges associated with applying activity-based models in travel demand forecasting. Additionally, the article explores the operational process of the ActivitySIM model, a specific ABM tool for traffic demand forecasting, by detailing the required input data and parameters. The potential for deploying this technology in Ho Chi Minh City was analyzed to highlight relevant data sources. Furthermore, the paper discusses potential solutions to improve data accuracy and enhance the consistency of ABMs across multiple days of the week, addressing critical challenges in implementing these models effectively.

Extending the theory of planned behavior to explore the intent to use electric motorcycles in Da Nang

Nguyen Van Bien — 2024-11-30

The continuous increase in the demand for personal vehicles, particularly fossil-fuel-powered two-wheeler, has become one of the main causes of air pollution. However, in recent years, electric motorcycle have gradually attracted consumer attention. Researching consumer intentions to use electric motorcycle plays a crucial role in understanding their needs, thereby proposing more effective measures to encourage the use of electric motorcycle in the future to reduce emissions contributing to environmental pollution. To achieve this, it is essential to analyze in depth the factors influencing the intention to use electric motorcycle. This study is based on an extended Theory of Planned Behavior (TPB) model, aiming to examine and evaluate the impact of perceived value and perceived cost on the behavior of using electric motorcycle. The PLS-SEM model was tested with data collected from 286 non-users of electric motorcycle in Da Nang City, Vietnam. Based on these analyses and findings, the study can help support the Government and manufacturers in devising specific solutions and comprehensive strategies to shift mindsets and attract consumers toward the intention to use electric motorcycle.

Flood mapping with impacts of the flood releases and dam failure of large reservoirs in the Vu Gia - Thu Bon River basin

Kieu Xuan Tuyen — 2024-11-30

Natural hazards are unusual natural phenomena that can cause damage to people, property, the environment, living conditions, and socio-economic activities. Currently, across the country, efforts are being made to prevent and control natural disasters. However, the damage caused by these natural disasters and floods tends to increase, and unusual phenomena become more and more extreme due to the following factors: global climate change, deforestation, and economic development that accelerates urbanization, industrialization, and the conversion of forest land into farmland. Floods and dam safety in river basins have been and are issues of social concern. Practical requirements in disaster reduction toward proactively responding to adverse situations that may occur in cases of flood discharge or dam failure and developing emergency response plans for floods in river basins to minimize the flood risks.

Formation process of “western” street architecture during French colonial period in Hue

Nguyen Ngoc Tung — 2024-11-30

This paper examines the architectural formation of the Le Loi “Western” street in Hue city by collecting secondary data through articles, magazines, images, books, maps, etc. and by conducting field surveys (mainly observation and taking photos). The built time of architectural buildings along Le Loi street can be divided into 3 periods: 1876-1902; 1093-1920; and 1921-1954. The architectural characteristic of the buildings constructed in early period was classical (neo-classicism) style, French local style. The later constructed buildings began to incorporate traditional local architecture, forming the Indochine architectural style. The constructions built after 1930 were in the Art Deco architectural style.

Greenwashing and the challenge of sustainable development in the construction industry

Pham Ngoc Thinh — 2024-11-30

Greenwashing, defined as the dissemination of inaccurate or misleading information regarding the environmental performance of products, services, or brands, has become increasingly prevalent in the construction industry. This study examines the extent and consequences of greenwashing in the sector, focusing on how exaggerated sustainability claims influence stakeholder trust and decision-making. Employing a mixed-methods approach - incorporating content analysis of corporate sustainability reports and surveys of industry experts - the research identifies common greenwashing strategies and evaluates their effects. Findings reveal that overstated environmental claims are pervasive, contributing to a significant decline in stakeholder trust. The discussion addresses the ethical implications of greenwashing, the challenges associated with its detection, and offers solutions to enhance transparency and accountability. This study advances the understanding of greenwashing within the construction industry and provides actionable recommendations to mitigate its negative impact on sustainability initiatives.

Identifying potential urban focal points using multiple centrality assessment (MCA): Da Nang’s center as a case study

Ngoc Hong Nguyen — 2024-11-30

Conventionally, identifying urban focal points is primarily based on subjective and intuitive evaluations. This paper aims to establish an objective method for identifying urban focal points by applying Multiple Centrality Assessment (MCA), a spatial network analysis tool. The authors calculate Betweenness, Straightness, and Closeness values within the urban street network and combine these metrics to generate a composite value, thereby identifying urban focal points in terms of connectivity and accessibility. This combined value is used to create maps of focal points and focal clusters, providing a scientific approach in this practice of urban design. The paper uses Da Nang City as a case study. The study’s results offer an evident-based approach in proposing urban focal points in urban design and planning.

Impacts of climate change on building performance and adaptation solutions

Nguyen Anh Tuan — 2024-11-30

Climate change has had significant impacts on the global climate, affecting the operational efficiency of buildings. This study employs future climate prediction methods based on the latest IPCC scenarios, using General Circulation Models (GCMs) to forecast climate conditions in three regions of Vietnam. Additionally, the study integrates simulation and simulation-based optimization methods to project the rise in greenhouse gas emissions and the level of thermal discomfort (overheating) in commercial buildings in Vietnam. The findings indicate that, due to the effects of climate change, carbon emissions from commercial buildings in Vietnam could increase by 6% to 22%, while the duration of overheating inside buildings may rise by several tens to several hundred percent.

Modelling of sediment diagenesis and its linkage with the water column. the case study of bay of quinte, Canada

Phuong T.K. Doan — 2024-11-30

In this study, the Aquasim model has been applied and developed to simulate the processes occurring in the sediments of the eutrophic system at Quinte Bay, Canada. The findings reveal that phosphorus (P) retention varies both spatially and temporally across the three basins of the Bay. These variations are influenced by factors such as sedimentation history, the chemical form of P, topography, and historical land use. According to the model, recent data indicates a decline in accumulated P at two shallow sediment sites (B and N), potentially leading to increased P release from these sediments. In contrast, the deeper sediment site (HB) continues to show high and stable P accumulation, resulting in consistently low and relatively unchanged P release. This explains why P levels in the Bay remain high, contributing to the growth of algae. The study also highlights the importance of adequately reducing external P loading. Internal P loads only play a supportive role in achieving the desired ecological conditions of the Bay.

Optimal conditions for synthesis of polyol-functionalized chitosan particles

Ho Hong Quyen — 2024-11-30

Adsorbents functionalized with polyol are considered to be effective for the removal of boron from aqueous solutions. In this work, polyol-functionalized chitosan particles were successfully synthesized. Batch experiments were conducted for the determination of the optimal conditions for the highest degree of gluconated groups being grafted to chitosan substrate. The results suggested that acetic acid is the most appropriate solvent for the dissolution of chitosan powder. Furthermore, an efficient mole ratio of 1:3 between chitosan and D-(+) - glucono - 1,5 lactone (DGL) was determined. The maximum level of gluconated groups grafted to chitosan was attained at a reaction temperature of 110°C and a reaction time of 24h. These optimized parameters exhibit potential for practical implementations in the boron removal from aqueous solutions.

Public preschool architecture in Ho Chi Minh city - assessing the current situation towards the development of children's emotional intelligence

Tan-Hanh Le — 2024-11-30

In preschool education, not only teaching methods but also the play-learning spaces play a crucial role in the holistic development of children. A good learning environment should not only focus on providing knowledge but also helps children develop emotional and social skills. Emotional Intelligence (EI) plays a key role in the development of these skills and needs to be integrated into the architectural design of preschools. Using the method of document analysis and actual survey, this paper focuses on analyzing the role of Emotional Intelligence in the design and construction of public preschools in Ho Chi Minh City. It also assesses the current status of existing architectural works and proposes design orientations aimed at optimizing play-learning spaces for children.

Research on calculation of slope failures considering unstable transient surface due to rain

Trung Quan NGUYEN — 2024-11-30

Slope landslides are one of the natural hazards that are gradually appearing more and more in number and intensity, causing serious damage to people, property, and infrastructure. Many studies have shown that climatic factors such as rainfall and human activities are important causes of landslides. The infiltration of rainfall changes the water content of the unsaturated zone (Vadose Zone), thereby causing instability. In this study, a 2-dimensional slope stability model was established using the seepage analysis module (SEEP/W) and stability (SLOPE/W), which considers the impact of rainfall changes, the existence of tree canopy and trunk, the soil reinforcement effect of tree roots, water absorption of tree roots, and the impact of tree roots on soil permeability, thereby calculating slope stability, applied to the Dak Pring hydropower plant project (Cha Val commune, Nam Giang district, Quang Nam province). The paper aims at a more comprehensive and detailed approach to seepage - slope stability calculation models than traditional solutions.

Research on proposing an effectiveness assessment criteria framework of residential and commercial building construction investment projects toward sustainable development in Nha Trang city

Le Huu Hau — 2024-11-30

In the context of global climate change, sustainable development has become a critical factor in housing and commercial construction projects. This research aims to propose a framework of criteria for evaluating the effectiveness of construction investment projects aligned with sustainable development goals. The proposed framework is divided into five key groups: time and cost efficiency, quality and safety performance, environmental protection, social accessibility and affordability, and satisfaction and legal compliance. A total of 21 criteria have been identified for empirical surveys. The study will collect and analyze data, assess the level of consensus, and rank the criteria accordingly. The research outcomes will provide a framework to assist regulatory agencies and investors in evaluating and selecting projects with sustainable development potential, thereby contributing to the long-term and comprehensive development of the city.

Research on solutions to improve quality management for design and survey work of construction projects: case study at Binh Duong construction inspection consulting company limited

Van-Tien Dang — 2024-11-30

To evaluate the suitability of locations and natural conditions for construction projects, designing and selecting foundation solutions must be conducted reasonably and cost-effectively. Binh Duong Construction Inspection Consulting Co., Ltd. has succeeded significantly in this field. However, improving quality management is essential to adapting to economic and technological integration and enhancing companies' competitive capacity in survey and design. This study focuses on identifying common mistakes and researching solutions to improve the quality of survey and design work for construction investment projects at Binh Duong Construction Inspection Consulting Co., Ltd. The results of this study not only support both the company and investors in minimizing risks and costs for construction projects but also contribute to the sustainable development of the construction industry generally.

Short-term prediction of regional energy consumption by metaheuristic optimized deep learning models

Ngoc-Quang Nguyen — 2024-11-30

Modern civilization is heavily dependent on energy, which burdens the energy sector. Therefore, a highly accurate energy consumption forecast is essential to provide valuable information for efficient energy distribution and storage. This study proposed a hybrid deep learning model, called I-CNN-JS, by incorporating a jellyfish search (JS) algorithm into an ImageNet-winning convolutional neural network (I-CNN) to predict week-ahead energy consumption. First, numerical data were encoded into grayscale images for input of the proposed model, showcasing the novelty of using image data for analysis. Second, a newly developed metaheuristic optimization algorithm, JS, was used to improving model accuracy. Results showed that the proposed method outperformed conventional numerical input methods. The optimized model yielded a mean absolute percentage error improvement of 0.5% compared to the default models, indicating that JS is a promising method for achieving the optimal hyperparameters. Sensitivity analysis further evaluated the impact of image pixel orientation on performance model.

Towards carbon neutrality in construction projects based on life cycle assessment

Nguyen Van Son — 2024-11-30

The construction industry is among the largest global consumers of natural resources and contributors to greenhouse gas emissions. This paper aims to evaluate current environmental standards and propose a new framework for reducing greenhouse gas emissions, targeting carbon neutrality in construction projects. The study employs the Life Cycle Assessment (LCA) methodology to assess the environmental impacts of civil buildings throughout their lifecycle, including material production, construction, operation, and disposal. Data were obtained from the IMPRO-Building project, which analyzed 72 building samples across three distinct climate zones in Europe. The findings indicate that high-rise buildings demonstrate greater energy efficiency compared to single-storey and multi-storey structures. Furthermore, climatic conditions significantly influence energy consumption, with cold climates exhibiting higher energy demands. The study recommends adopting LCA-based standards to mitigate environmental impacts, thereby promoting the sustainable development of the construction industry.

Vehicle routing problem in waste collection: a case study in Son Tra, Da Nang

Le Hoang Son — 2024-11-30

This study investigates the application of network analysis to optimize solid waste collection routes in Son Tra District, Da Nang City. Twelve collection routes, encompassing 30 collection points, were tracked using GPS equipment and digitized in QGIS. Key parameters such as length, velocity, and time were analyzed. By employing the Dijkstra algorithm, route optimization resulted in a significant reduction in average route length, from 12.94 ± 3.5 km to 9.42 ± 2.67 km, representing a 9-42% improvement. A paired sample t-test confirmed the statistical significance of this reduction (p<0.001). These findings demonstrate the potential of network analysis to optimize waste collection routes and reduce operational costs. However, the model's limitations, such as its focus on static, point-based collection routes and the exclusion of dynamic factors like traffic conditions and residential habits, should be considered for future research.

Waterscapes: the cultural heritage for sustainable development in the urban structure of Hue city in Vietnam

Vo Ngoc Duc — 2024-11-30

For many years, waterscapes have used as indispensable architectural elements in urban design like Amsterdam, Venice, etc. Similarly, from 1802 to 1945, the integration of water into the layout of Hue city exemplified sustainable urban planning. Additionally, Feng Shui method positions water as a crucial component Hue city which represents a unique harmony between humans and nature, reflecting Eastern philosophical ideas and traditional Vietnamese architecture. The waterway model was seamlessly integrated with the waterscape and monuments, establishing the unique identity for the local ecosystem. In recent decades, Hue’s waterscape has undergone considerable change due to urbanization, environmental pollution, flooding, and disruption of water flow. These factors have altered the characteristics of traditional waterscape and negatively affected the previous concept of water system. Identifying the characteristics and values of the traditional water network is as cultural heritage to preserve and promote a sustainable model that adapts with local environmental self-regulating technology.