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Hybrid Electric Vehicles (HEVs) are a promising option to reduce transportation emissions while the adoption of pure electric vehicles is still low in many countries. This study aims to examine the factors that affect the fuel economy and the emission performance of a HEV compared to a Conventional Vehicle (CV) with a traditional Internal Combustion Engine (ICE) under different real driving conditions. In order to analyze the energy efficiency of the HEV, this paper proposes an experimental method based on empirical data to estimate the equivalent Fuel Consumption (FC) of the energy supplied by the Electric Motor (EM). Then this parameter is used to compare the fuel efficiency of the HEV and the CV, which have similar specifications, in order to demonstrate that the hybrid configuration has better fuel economy than the combustion engine configuration. The test vehicles' performance is evaluated in different Driving Cycles (DCs) in Hanoi. Moreover, the time and the distance with zero-emission rates and regenerative energy efficiency are presented to assess the HEV's energy management strategy and environmental benefits in different Hanoi's driving scenarios. [ABSTRACT FROM AUTHOR]

This paper discusses the development of artistic collaboration during the global lockdown, related to the COVID-19 pandemic. The art work under study involves the author’s practices of ecological sound art and intercultural collaboration in collaboration with Canadian composer and improviser John Oliver. A primary outcome of this work was the album Isolation Journal, released in 2020, in the midst of the pandemic. One feature of Isolation Journal was how it revisited site-specific recordings made in Vietnam, on the countryside north of Hanoi, for an installation made by Östersjö in collaboration with Nguyễn Thanh Thủy and Matthew Sansom [Östersjö, Stefan, and Thanh Thủy Nguyễn. 2016. “The Sounds of Hanoi and the After-Image of the Homeland.” Journal of Sonic Studies 12. https://www.researchcatalogue.net/view/246523/246546]. Through remote interactions, and by building a complex sampler instrument using Östersjö's recordings of Aeolian đàn đáy, a traditional Vietnamese lute, as well as field recordings from the site, Oliver and Östersjö created the album Isolation Journal through remote interaction. This in turn became a fundamental building block when the author's Vietnamese/Swedish group The Six Tones took the initiative to develop a scene for telematic performance at Manzi Art Space in Hanoi. This series started out with a concert with John Oliver, The Six Tones and guest performers from Hanoi in July 2020. Building on audio and video documentation, as well as on qualitative interviews with the participating co-performers, an analysis of the emergence of discursive voice [Gorton, David, and Stefan Östersjö. 2019. “Austerity Measures I: Performing the Discursive Voice.” In Voices, Bodies, Practices: Performing Musical Subjectivities, edited by Catherine Laws, William Brooks, David Gorton, Nguyễn Thanh Thủy, Stefan Östersjö, and Jeremy J. Wells, 29–79. Orpheus Institute Series. Leuven: Leuven University Press] is drawn from these two internally linked artistic projects. The paper develops the analytical framework of tele-copresence, a synthesis of the contrasting concepts of telepresence and copresence, as a means for analysing the virtual presence which emerges through such remote musical interaction.  [ABSTRACT FROM AUTHOR]

In this paper, we consider Tower of Hanoi graphs and study their matching properties. Explicit system of recurrences is derived for the matching polynomials of these graphs and their appropriate truncated variants. Consequently, we obtain exact formula for the numbers of maximum matchings in Hanoi graphs using matching polynomials, which is a new approach for old one problem. [ABSTRACT FROM AUTHOR]

In order to address the energy imbalance issue of a series-connected lithium-iron battery pack, this paper proposes an active equalization method based on a reduced-order solving strategy for the Hanoi Tower problem. The proposed scheme utilizes a combined structure of a switching-network circuit and a bidirectional Cuk converter and leverages an ultracapacitor cell as the energy-transfer carrier. Simulation and comparison demonstrate that the exchange of unbalanced energy within the battery pack can be achieved. The proposed approach can effectively achieve various balancing modes such as cell-to-cell, cell-to-string, string-to-cell, and string-to-string with a relatively fast balancing speed. [ABSTRACT FROM AUTHOR]

Blockage, which arises from accumulated materials like sand, stones, sediment, uncontrolled growth of tree roots within pipes, and the inadvertent partial closure of in-line valves, poses a pervasive challenge in the operational sphere of water distribution networks (WDNs). This results in significant head loss in the pipes, leading to disruptions in the water supply. Identifying such blockages conventionally requires specialized human resources and is often encumbered by cost and time challenges. This paper introduces a method for precisely determining the location and magnitude of blockages within WDNs. This methodology is firmly grounded in a calibration-optimization framework, harnessing a specially crafted hybrid optimization algorithm known as PSOHS, which combines the strengths of particle swarm optimization (PSO) and harmony search (HS) algorithms. Detailed comparisons are drawn between simulated pressure data (derived from the hydraulic network model) and corresponding field data at multiple points to minimize disparities, thereby facilitating the precise identification of potential blockages in a WDN. The proposed method undergoes rigorous evaluation across two benchmark networks (modified Poulakis and Hanoi) under diverse scenarios as well as on an actual WDN. Results from over 60,000 simulated blockage scenarios underscore the method's remarkable proficiency, achieving blockage localization accuracy of 99.9% and magnitude estimation with a maximum absolute error (MAE) of less than 3%. Particularly noteworthy is the superior performance of the PSOHS algorithm as proposed, surpassing the PSO algorithm by enhancing blockage localization accuracy by a minimum of 10.5% and reducing MAE by 3%. Further, adopting the proposed algorithm over the HS algorithm yields improvements of 27.5% and 3.5%, respectively. Applying the proposed method in an actual network effectively pinpointed its blockage. Consequently, this algorithm presents a valuable tool for WDN operators, augmenting their capacity for effective network management. [ABSTRACT FROM AUTHOR]

Vietnam's new manufacturing status is driven in part by South Korean investments. This paper examines two groups of expatriate Koreans in Hanoi--skilled/managerial workers and the Korean small-business workers. The high concentration of expatriate workers in Hanoi has given rise to the Korean ethnic enclave of My Dinh, many of whose establishments are owned, managed, and serviced by Koreans. The easy availability of services offered by these businesses enables a culture-based support of Korean expatriates in a new city, and the reproduction of Korean life through consumption. Our paper contributes to the literature on the ethnic economy by identifying the nature of customer support for Korean ethnic enterprises. By highlighting the Korean-owned-and-managed small business character of the urban ethnic economy, we demonstrate the importance of consumption in allowing Korean ways of life to be maintained in a new city. We extend our analysis to Vietnamese consumers of Korean businesses and argue tat such enterprises create new opportunities for the growing Vietnamese middle class to develop new consumption practices in a growing cosmopolitan city. [ABSTRACT FROM AUTHOR]

This paper investigates the COVID-19 vaccine diplomacy of the United States and China in Vietnam and conceptualises Hanoi's practical responses. The deployment of vaccine diplomacy is closely associated with US-China strategic rivalry and is thus labelled as proxy competition in this paper. This paper found that both Washington and Beijing leveraged vaccine diplomacy to achieve general strategic objectives and specific foreign policy objectives in relations with Vietnam. For the USA, vaccine donation consolidated Hanoi's strategic trust in Washington during tough times. Meanwhile, despite widespread mistrust and suspicion regarding the quality and efficacy of Chinese-made vaccines amongst Vietnamese people, China's vaccine donation to Vietnam could still prevent Hanoi from further spiraling into the US-led anti-China coalition. Nevertheless, Vietnam has constantly been at a crossroads, for it not only strives to respond reasonably to the USA and China at the international level but also has to accommodate the Vietnamese public's policy preferences at the domestic level. [ABSTRACT FROM AUTHOR]

This paper aims to explore the effect of integrated marketing communication (IMC) on marketing performance in hospitality industry. From firm-wide approach, IMC is viewed more broadly with its integration throughout the organization, not only integration of mass media elements to produce a consistent message. This approach has improved IMC measurements, but many studies have neglected the roles of controlling of the IMC process, the difference in the impacts of IMC on marketing performance between chain hotels and independent hotels has not been examined and evaluated. This paper completes measurement scales and evaluates the effects of IMC on marketing performance in the hospitality industry by using primary data collected from 198 managers of various levels from 4-to-5-star hotels in Hanoi - the capital of Vietnam, including chain hotels and independent hotels. The research findings reveal IMC factors that have an effect on overall marketing performance (including sales-related performance and brand-related performance) and the difference in their effect on 2 groups of hotels. Specifically, with chain hotels, 5 factors affecting the marketing performance in declining order are interactivity, controlling, consistent communication, planning and organizational infrastructure while with independent hotels, the factors with effects in declining order are controlling, planning, consistent communication, interactivity and organizational infrastructure. The study provides some recommendations regarding the IMC process to improve the sales-related performance and brand-related performance of chain hotels and independent hotels. [ABSTRACT FROM AUTHOR]

Sustainable development is a subject of study and consideration by scientists and policymakers, especially the sustainable development of the night-time economy. The night-time economy refers to the various economic activities and businesses that primarily operate during the evening and night hours, typically from 6 p.m. until early morning. It includes a diverse range of sectors such as entertainment, dining, hospitality, and nightlife, with establishments such as bars, clubs, restaurants, theaters, and live music venues playing a significant role. The development of the night-time economy refers to the process of managing and promoting the growth of economic activities during the evening and night hours in a manner that balances economic, social, and environmental considerations. Therefore, the paper aimed to identify the factors affecting the night-time economy in Hanoi to achieve the sustainable development of this economy. The paper processed and analyzed the data using SPSS Statistics 26.0 software. The quantitative study included (1) testing the suitability of the scale for the variables using Cronbach's alpha, (2) analyzing the EFA factors to check the convergence of the observed variables and the separation between the independent variables, (3) checking the correlation to evaluate the problem of multicollinearity of the model, and (4) performing regression analysis to evaluate the impact of the factors on night-time economic development in Hanoi City. The empirical results showed that the variables positively impacted night-time economic development in Hanoi. However, the study found differences in the levels of their impact. Among the four factors, factor 3 (promotion and sharing) had the strongest impact on night-time economic development, followed by factor 2 (city infrastructure and safety), factor 1 (institutions and environment), and factor 4 (nature and resources). The empirical results will help policymakers promote the sustained development of the night-time economy in Hanoi, Vietnam. [ABSTRACT FROM AUTHOR]

This paper critically discusses the Hanoi Metro and its role in contemporary urban development processes in Hanoi. It aims to disentangle the complex interplay between the state's urban development goals, local mobility patterns, and Sino-Vietnamese relations that influence discourses surrounding the Hanoi Metro. This paper argues that the Hanoi Metro project demonstrates that mobility infrastructures serve as an arena for state-society negotiations in Vietnamese cities. Rooted in the state's vision of modernity, the metro is promoted as offering an alternative to individual motorized transport, improving urban traffic and mobility for all residents. However, controversies regarding corruption, safety, and Chinese involvement in the financing and construction of Line 2A have negatively affected public perception of the project during its construction period. The potential impact of the Hanoi Metro on urban mobility in a setting dominated by motorbikes is discussed using the mobilities paradigm, with a focus on local mobility practices and experiences. The findings are linked to broader discussions on Chinese investment and historically-rooted notions of modernity and civilization in the context of the long-term development goals of municipal authorities and rising anti-Chinese sentiments in Vietnamese society. [ABSTRACT FROM AUTHOR]

Metro line 3 in Hanoi is being constructed using tunnels, which may affect nearby constructions. In addition, Hanoi's earthquakes also pose risks to this Tunnel Boring Machine (TBM) line. This paper studies the impact of TBM construction on the surrounding houses along the line, as well as the impact of earthquakes on this line. A 3D numerical model was developed to simulate the static and dynamic behavior of TBM at station 9 in Metro Line 3. The results show that the maximum settlement at the ground surface under seismic load is significantly reduced from 4.6 mm to 0.1 mm when using the jet grouting method. [ABSTRACT FROM AUTHOR]

Objective - As Vietnam is a densely populated country with stable economic growth and rising concern for environmental problems in recent years, people are increasingly showing more interest in organic food. This study aims to explore the purchase intention of Vietnamese Generation Z (Gen Z) towards organic food. Methodology - We extended the Theory of Planned Behaviour (TPB) with three specific pro-environmental factors that are health consciousness, environmental concern, and knowledge of organic food, to investigate the purchase intention of Gen Z. A self-administered online survey was conducted in Hanoi, Da Nang, and Ho Chi Minh City as they are most populated cities in the country. Findings – 426 valid responses were received for data analysis after three months. Linear regression analysis was run in SPSS software to test six hypotheses. Research findings reveal that attitude has the most substantial influence on the purchase intention of Gen Z, followed by health consciousness, subjective norms, and personal norms. Notably, environmental concerns and knowledge of organic food do not necessarily affect Gen Z’s purchase intention. Our findings suggest that related stakeholders in the organic food market adjust their production and marketing tactics to attract Gen Z better. Novelty – The novelty of this paper is attributed to our effort to integrate pro-environmental variables into the TPB to test their impact on organic food purchase intention in a new research context of a transition country. [ABSTRACT FROM AUTHOR]

This research investigates consumers' stated attitudes and behaviors towards plastic bag consumption in Hanoi wet markets. The project leveraged a stated preference survey (SPS) and background demographic survey of the consumers at two wet markets to run a linear regression and determine the "value" that the general Vietnamese population places on plastic bags compared to alternatives. Altogether, the demographic survey gathered 163 responses and SPS 235 responses. The SPS provided survey respondents with four different options to store the vegetables they bought in the wet market: plastic bag, paper bag, ecofriendly tote bag, or a reusable bag. Four different attributes (price, volume item can hold, weight item can hold, and the number of times item can be used) and their respective levels were presented. The analysis (p<0.05) showed that price and functionality are the two most important actors in deciding whether a consumer would use a plastic bag or an alternative at the wet market. For each additional unit kilogram that an item, could hold, the probability of a person purchasing that item decreased by 3.21%. On the other hand, a unit increase in price (measured in VND) decreased the probability that a person would purchase the item by 0.0001178%. Ultimately, despite the current excessive use of plastic bags, the general Vietnamese demographic (91%) demonstrated a shift or a desire for a shift towards the adoption of plastic alternatives. [ABSTRACT FROM AUTHOR]

Copyright of European Journal of Development Research is the property of Palgrave Macmillan Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present study promotes a new algorithm for estimating the water pollution propagation with the primary goal of providing more reliable and high quality estimates to decision makers. To date, the widely used variational method suffers from the large computational burden, which limits its application in practice. Moreover, this method, considering the initial state as a control variable, is very sensitive in specifying initial error, especially for unstable dynamical systems. The Neural Network Filter (NNF), proposed in the present paper, is aimed at overcoming these two drawbacks in the variational method: by its nature, the NNF is sequential (no batch large assimilation window used) and stable even for unstable dynamics, with the gain parameters as control variables. The NNF, developed in the present paper, is a Neural Network Filter (NNF) version of the Singular Evolutive Interpolated Kalman Filter (SEIKF). One of the new versions of this NNF is that it uses structure of the gain of SEIKF0 taken by the SEIKF at the first time moment of correction process. To deal with the uncertainty of the system parameters and of the noise covariance, the proposed Neural Network SEIKF0 named by NNSEIKF0 makes use of the covariance of a reduced rank iterated during assimilation process and of some pertinent gain parameters tuned adaptively to yield the minimum prediction error for the system output. The computational burden in implementation of the NNSEIKF0 is reduced drastically due to applying the optimization tool known as a simultaneous perturbation stochastic approximation (SPSA) algorithm, which requires only two integrations of the numerical model. No iterative loop is required at each assimilation instant as usually happens with the standard gradient descent optimization algorithms. Data assimilation experiment, carried out by the SEIKF0 and NNSEIKF0, is implemented for the Thanh Nhan Lake in Hanoi and the performance comparison between the NNSEIKF0 and SEIKF0 is given to show the high efficiency of the proposed NNSEIKF0. [ABSTRACT FROM AUTHOR]

The Mother Goddess Worship's (MGW) private shrine—Điện thờ Mẫu tư gia—has been a prominent worshipping place of a Vietnamese folk religion; however, it is rarely documented in scholarship in both Vietnamese and English. This paper is based mainly on in-depth interviews and numerous follow-up conversations with sixteen MGW spirit mediums in Hanoi capital city, additionally verified and supported by the authors' field notes. The findings reveal that worshipping Buddha(s) at MGW private shrines is a remarkable phenomenon and becoming common; however, they vary at different levels because of different reasons in which non-religious causes are significantly considered. The absence of worshipping Buddha(s), if there is any, is explained by the problems of lacking space or being in serious spiritual conflicts that cannot be avoided. In those cases, a Buddha(s) altar is often immediately added when the space is improved, and Buddha(s) statues/pictures are still displayed. Furthermore, the continuous blending of MGW—a Vietnamese folk religion—with Buddhism—a world religion—is proved to be not only a way that religious people choose to nurture their faith and seek preferable religious practices but additionally to be flexible to adapt their religion in the modern era. Finally, regarding religious freedom and tolerance, we argue that private shrines are able to be active freely without any control by the government such as they used to be prohibited in the past. In some circumstances, government officers also benefit from services offered by local mediums, even though they might not be MGW followers. Furthermore, mediums' neighbors are friendly to or even enjoy shrines' activities. Such facts show the improvement in religious freedom in Vietnam in recent decades, as well as once again proving the tolerance of the Vietnamese people towards different religions and beliefs. [ABSTRACT FROM AUTHOR]

The relationship between Earnings Management (EM) and Corporate Social Responsibilities (CSR) has raised a considerable number of attentions, especially, in financial and accounting field since they determine firms' performance as well as market positioning. On the contrary, in an emerging country as Vietnam, the number of relevant studies are rare together with several limitations. Thus, this paper is the pioneer investigating the cause and effect among Accruals Earnings Management (AEM), Real Earnings Management (REM) as two proxies for EM, and CSR. Next, Granger's causality replacing for traditional method is employed in order to interpret this nexus. The analysis relies on the sample size of 225 companies during the period 2014–2018 from Hanoi Stock Exchange (HNX) and Ho Chi Minh Stock Exchange (HOSE). We figured out executives prefer REM to AEM when implementing earnings manipulations. Consistent with the expectations and prior scholars, we found there is a negative correlation in the association of AEM and CSR while it is positive in the case of REM and CSR. Besides the consistent results with multivariate regression analysis (MRA) in terms of CSR-EM association, the fsQCA findings also explore more combinations regarding the relationship between CSR-EM. Additionally, all empirical results also provide evidence that there is cause-and-effect relationship in terms of AEM, REM and CSR which has never been researched and discussed over the past several years. [ABSTRACT FROM AUTHOR]

In millimeter wave communication systems, the construction of a path loss model that is close to empirical one plays an important role in planning coverage, system capacity, and link budgets. In this paper, we propose a novel approach applied unsupervised machine learning for propagation pathloss estimation in millimeter wave communication systems based on the iterative procedure of cooperative and iterative evaluation exchange (Co-IEE) algorithm. The propagation path loss models of the time city–an urban area in the center of Hanoi, Vietnam in both line-of-sight (LOS) and non line-of-sight (NLOS) are estimated and calculated using the proposed approach and then they are compared to the minimum mean square error (MMSE). The estimated results of the proposed model show the approximation with the optimum one returned by MMSE method. Moreover, the proposed model of estimating path loss can solve the problem of sensitivity with outliers existing in MMSE and give more choices for path loss exponents. [ABSTRACT FROM AUTHOR]

This paper aims to cluster politically affiliated groups using machine learning. The sample used in the study is enterprises listed on the stock exchanges of Ho Chi Minh City and Hanoi, research data during the period from 2015 to 2020. Data used in the study include state ownership ratio, the degree of political connection of business leaders and financial indicators in the listed financial statements of enterprises. The author's study measures political connection by K-means algorithm and then compares the results of the K-means clustering with the traditional method of manual measurement of political connection including two values of 0 and 1, where 0 is no political affiliation and 1 is political affiliation. At the same time, the author runs three clusters to have in-depth insight. The authors conclude that machine learning clustering using the k-means model can replace the traditional method. Politically connected businesses listed on HOSE and HNX with political connections bring many benefits to businesses in investment activities, in accessing resources as well as capital; however, that businesses have a negative impact on business performance. The authors recommend that a moderate degree of political affiliation will help businesses achieve better performance. [ABSTRACT FROM AUTHOR]

This paper focuses on modes of stabilities and mobilities within a park in central Hanoi where the past and present intersect as tourists and locals visit and interact with each other as well as with the visual and aural resources. We document the transformable nature of what is represented in space and time by considering how the material artefacts, the written resources inscribed in space, the aural resources created by various actors and their mobility collectively mark the space. Over time, some resources remain, others leave momentary traces, while still others re-emerge in similar but not identical forms, creating multiple layerings of this urban palimpsest. This paper documents some of these layerings and considers how they inform our understandings of the ways stabilities interact to enable and disenable mobilities in semiotic systems. [ABSTRACT FROM AUTHOR]

Copyright of Conhecimento & Diversidade is the property of Conhecimento & Diversidade and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cultural professionals in the art and cultural sector in Hanoi, Vietnam, are carrying out digitization projects and utilizing digital platforms, tools and applications in order to curate their own narrative on Vietnamese art and culture. This can help to counter digital orientalism by redressing the imbalance in the amount of accessible content online as well as control over the production and circulation of cultural content. An increase in the amount of digitized cultural content can help to engage local audiences and introduce a contemporary image of Vietnamese culture to an international audience. Today, Vietnamese cultural professionals are able to decide what to digitize, what to make publicly accessible and how to curate it online. This paper presents findings from a case study on Manzi Art Space, including a digital ethnography of an augmented reality public art project entitled 'Into Thin Air' and 20 interviews with art and cultural professionals working in Hanoi. The findings show how digitization allows cultural professionals to shape the narrative on contemporary Vietnamese art and culture. However, the findings also show there are particular challenges faced by cultural professionals in Hanoi, including lack of human resources, technical resources and funding as well as concerns around copyright law and government permissions. These challenges are hindering the ability to utilize new digital technologies. [ABSTRACT FROM AUTHOR]

Purpose: The paper aims to ascertain whether residents in Nguyen Du ward still sort their waste at source following the end of the 3R project that ended in 2009. Additionally, this paper aims to explore the relationship between waste separation practices and social bonds. Design/methodology/approach: The Travis Hirschi theory of social control was applied, together with the mixed method research design which included a structured questionnaire survey. Twelve semi-structured interviews were also conducted with residents and the data processed by SPSS software, using Chi-Square test, Independent-Samples t-test and Pearson's correlation analysis. Findings: A proportion of respondents has continued practicing waste separation since the 3R project ended. The study also indicated that the greater the involvement in family and neighborhood activities the more the participants were likely to practice waste separation. Research limitations/implications: The small sample size limits the extent to which the most influential factors can be determined and therefore the degree to which the findings can be generalized. Practical implications: The study includes implications for rerunning the waste separation programs for households as together with community campaigns to improve individuals' attachment and commitment and thus their participation in pro-environmental behaviors. Originality/value: To the author's knowledge, this is the first study to take a sociological approach to investigate factors affecting household waste separation, which has attracted little attention in previous studies. Useful information is also provided to local authorities for a policy-making process to implement effective domestic waste policies. [ABSTRACT FROM AUTHOR]

This paper introduces an advanced method that integrates contingent valuation and machine learning (CVML) to estimate residents' demand for reducing or mitigating environmental pollution and climate change. To be precise, CVML is an innovative hybrid machine learning model, and it can leverage a limited amount of survey data for prediction and data enrichment purposes. The model comprises two interconnected modules: Module I, an unsupervised learning algorithm, and Module II, a supervised learning algorithm. Module I is responsible for grouping the data into groups based on common characteristics, thereby grouping the corresponding dependent variable, whereas Module II is in charge of demonstrating the ability to predict and the capacity to appropriately assign new samples to their respective categories based on input attributes. Taking a survey on the topic of air pollution in Hanoi in 2019 as an example, we found that CVML can predict households' willingness to pay for polluted air mitigation at a high degree of accuracy (i.e., 98%). We found that CVML can help users reduce costs or save resources because it makes use of secondary data that are available on many open data sources. These findings suggest that CVML is a sound and practical method that could be widely applied in a wide range of fields, particularly in environmental economics and sustainability science. In practice, CVML could be used to support decision-makers in improving the financial resources to maintain and/or further support many environmental programs in years to come. [ABSTRACT FROM AUTHOR]

In recent years, Vietnam has had many construction incidents related to deep excavation construction. Notably, the incidents of constructing the underground of a high-rise building such as the excavation collapsing, subsidence of the ground around the deep excavation, diaphragm walls move significantly beyond the allowable value, etc. Construction solutions, which can stabilize the deep excavation and reduce the displacement of diaphragm walls, are very important and extremely necessary. The paper presents the effect of the increasing load from the strut system by hydraulic jack (active support system) to the Barrette wall displacement during the construction of the deep excavation. In this study, a numerical investigation was performed to evaluate the effect of the active support system on the Barrette wall displacement corresponding to each case of 2 to 3 basements for each type of natural ground in Hanoi city. In particular, the Finite Element Model (FEM) simulated the construction sequence of deep excavation with different forces from struts has been compared. The analysis results show that the active support system is an effective solution to stabilize the deep excavation and reduce the horizontal displacement of the Barrette wall, especially the top and the middle of the Barrette wall. [ABSTRACT FROM AUTHOR]

In Vietnam's capital city Hanoi, the growing popularity of application based (app‐based) motorbike taxis has offered many inhabitants new opportunities to pursue a mobile livelihood with ride‐hailing platforms. Nonetheless, as this influx of app‐based drivers has hit the city's streets, specific livelihood and mobility frictions have emerged, notably with informal, 'traditional' motorbike taxi drivers, or xe ôm. In this paper we analyse these evolving sites and moments of friction and their impacts on driver livelihoods and mobilities for both driver groups. We draw conceptually on debates regarding mobility, platform economies, and urban livelihoods, while specifically interrogating the concept of friction to highlight three possible analytical applications. Methodologically, we interpret static and ride‐along interviews completed with over 130 drivers. We highlight a range of tactics 'traditional' and app‐based motorbike taxi drivers have employed to respond to rising frictions, defend their 'turf', and maintain their street‐based livelihoods. Driver responses reveal differing access to distinctive forms of social capital and social networks, and contrasting levels of agency regarding their mobilities. By conceptually teasing apart the notion of friction, we wish to expand and deepen understandings of the experiences of vulnerability, precarity, and other impacts of platformisation for different motorbike taxi driver cohorts. [ABSTRACT FROM AUTHOR]

Public gardens in urban areas play an important role in the development of physical and mental health of the people. These spaces are also social spaces, where people meet to interact, exchange, and organize collective activities. They create a unique identity for each residential area in the city, which is a premise for green urban development. In Hanoi, public flower gardens (PFGs) were formed and developed from the French colonial period, mainly those in the historic city centre. Facing the forceful urbanization process and the changing of urban structure, in order to evaluate the role of all public flower gardens in the historic city centre area, we carried out a systematic survey from 2019 to 2022. We surveyed all 30 PFGs in five central districts of Hanoi, and interviewed 229 users at these gardens. We also conducted research on relevant documents regarding the management and planning of green space and water infrastructure in the city. Moreover, we implemented an experimental workshop, combining an urban living lab (ULL) approach and an in situ landscape approach, to develop urban landscape design ideas with community participation. Based on the data from this research, this paper analyzes the potential for the establishment of urban blue-green infrastructure (BGI) from these PFGs and aims to evaluate the role of community participation in landscape design for the city. Data from multiple collection methods provide a multi-faceted understanding of the original characteristics of the PFGs in Hanoi and their importance in urban life. The project results supply experimental lessons from urban landscape design activities through community participation, which opens up the potential for developing sustainable urban spaces based on existing natural structures in the city. The main result proves that active community participation until the end of the research project raises public awareness and ensures the social acceptance of the final design. These lessons allow the improvement of urban landscape design practices and the establishment of BGIs from PFGs in an efficient and sustainable manner for green cities in the future. [ABSTRACT FROM AUTHOR]

Autonomous robots start to be integrated in human environments where explicit and implicit social norms guide the behavior of all agents. To assure safety and predictability, these artificial agents should act in accordance with the applicable social norms. However, it is not straightforward to define these rules and incorporate them in an agent's policy. Particularly because social norms are often implicit and environment specific. In this paper, we propose a novel iterative approach to extract a set of rules from observed human trajectories. This hybrid method combines the strengths of inverse reinforcement learning and inductive logic programming. We experimentally show how our method successfully induces a compact logic program which represents the behavioral constraints applicable in a Tower of Hanoi and a traffic simulator environment. The induced program is adopted as prior knowledge by a model-free reinforcement learning agent to speed up training and prevent any social norm violation during exploration and deployment. Moreover, expressing norms as a logic program provides improved interpretability, which is an important pillar in the design of safe artificial agents, as well as transferability to similar environments. [ABSTRACT FROM AUTHOR]

As a developing country, Vietnam has experienced rapid economic development since the 21st century. It is therefore becoming increasingly important to understand its spatial pattern of urban expansion. However, the key challenge in this endeavor lies in the lack of national accounting data for the sub-administrative divisions of Vietnam at the national level, especially longitudinal data over a long time series. The nighttime lights (NTL) data can objectively reflect the scope and intensity of human development and construction in urban built-up areas, which can effectively support the empirical analysis of the urban expansion process in Vietnam. This paper uses the intercalibration model to correct and fit the long time series of DMSP/OLS and VIIRS/NPP NTL data. Based on this, the data for the urban built areas of Vietnam from 2000 to 2018 are further extracted. The results are as follows. (1) The main urban expansion in Vietnam is concentrated in the southern Mekong Delta and the northern Red River Delta, represented by Ho Chi Minh City and Hanoi City, respectively. (2) Vietnam's urban NTL has significant high–high clustering characteristics in the north-south delta regions. The main urban expansion hotspots were concentrated around Ho Chi Minh City before 2012, the northern region represented by Hanoi City was gradually transformed into a critical area that gathering urban expansion hotspots after 2012. (3) The cities with significant influence and high coupling degree of industrialization and globalization on the urbanization of Vietnam are concentrated in Ho Chi Minh City, Hanoi, and some northern delta provinces, showing that the impact of industrialization and globalization on urbanization in Vietnam is still limited to some regions. In addition, the results show that the size of the population and the level of industrialization are the main drivers of urban expansion in Vietnam, while the level of foreign investment shows little significance. The results are helpful for promoting the application of long time series NTL data in urban expansion and for further analyzing the urban pattern changes in Vietnam and the influencing factors behind them. [ABSTRACT FROM AUTHOR]

This paper unveils the accumulated tensions and conflicts in North Korean-Vietnamese relations in the late 1970s. From diplomatic competition to ideological gap, the once comrades-in-arms found themselves gradually drifting apart. But it was not until Vietnamese troops entered Cambodia that the traditional friendship was severely damaged. Economic cooperation deteriorated due to the North's criticism of Vietnam and Kim Il Sung's support for Democratic Kampuchea. Still, this paper emphasizes that a key source of the Pyongyang-Hanoi discord lay in their mutual perceptions and evaluations of each other's accomplishments in nation-building and achieving reunification. [ABSTRACT FROM AUTHOR]

An increasing number of urban residents in the Global South are turning to rooftop gardening, whether through soil or hydroponics, to cultivate their own vegetables, fruit, and herbs. In Hanoi, Vietnam's capital, rooftop gardening serves as an important alternative to traditional wet markets and more recently established supermarkets. In this paper, we examine the motivations, practices, and constraints of Hanoi's rooftop gardeners, along with the level of government support or disapproval for rooftop gardening. Our study is grounded in critical urban geography and urban political ecology and specific debates regarding informal life politics. Our findings reveal that Hanoi's rooftop gardeners feel confronted by a critical food safety crisis, emphasising their need to access safe, fresh, and affordable produce through rooftop gardening. Simultaneously, they express scepticism about the capacity and willingness of formal political institutions at both the municipal and national levels to address and resolve these concerns. We explore whether Hanoi's urban rooftop gardeners can be considered to be engaging in a form of everyday life politics and examine the dynamics emerging in this regard. We conclude by offering potential policy recommendations for Global South cities to support urban gardening communities. [ABSTRACT FROM AUTHOR]

The stability of the tunnel face during tunneling is one of the major criteria for the design and construction of the tunnel. Collapse and blowout are two modes of tunnel face failure during the excavation. The cover-to-diameter ratio is one of the main parameters controlling these failure modes. Several analytical solutions have been proposed to estimate the range of support pressure applied on the tunnel face to avoid both the collapse and the blowout. However, most of those models deal with homogeneous soils. This paper aims at proposing an analytical model to predict the blowout of the tunneling face of a tunnel in multi-layered soils. The derivation is based on a limit equilibrium analysis, which considers the water tCiable. The proposed model is validated against the real blowout data reported from the tunneling in the Second Heinenoord Tunnel project in the Netherlands. Then, the maximum support pressure exerted on the tunneling face is predicted as a function of the cover-to-diameter ratio, the tunnel diameter, and the water table level for five representative soils. Finally, the model is applied to an underground segment of the Hanoi Metro Line 3 project (in Vietnam) to show the role of the multi-layer aspect. [ABSTRACT FROM AUTHOR]

In this paper, we obtain some new identities of Lucas sequences and establish relationships with Fibonacci and Tribonacci sequences. We propose the generalized Fibonacci trace sequences which give the generalized Lucas sequences {lk,n}k≥2 of order k as defined by the recurrence relation lk,n+k = lk,n + lk,n+1 + ... + lk,n+(k−1) with initial conditions as solution of Hanoi Tower sequences. Further, the associated recursive matrices has been developed and studied. [ABSTRACT FROM AUTHOR]

Copyright of Urban Studies (Sage Publications, Ltd.) is the property of Sage Publications, Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Continuous improvement in computing power allowed for an increase of the scales micro-traffic models can be used at. Among them, agent-based frameworks are now appropriate for studying ordinary traffic conditions at city-scale, but remain difficult to adapt, especially for non-computer scientists, to more specific application contexts (e.g., car accidents, evacuation following a natural disaster), that require integrating particular behaviors for the agents. In this paper, we present a built-in model integrated into the GAMA open-source modeling and simulation platform, allowing the modeler to easily define traffic simulations with a detailed representation of the driver's operational behaviors. In particular, it allows modelling road infrastructures and traffic signals, change of lanes by driver agents and less normative traffic mixing car and motorbike as in some South East Asian countries. Moreover, the model allows to carry out city-level simulations with tens of thousands of driver agents. An experiment carried out shows that the model can accurately reproduce the traffic in Hanoi, Vietnam. [ABSTRACT FROM AUTHOR]

As a central component of the "green city" narrative, urban agriculture is gaining importance in urban planning and global sustainability agendas. In Hanoi, the capital city of Vietnam, the "green city" is core to the state's urbanisation agenda, with a green corridor envisioned as part of the city's Master Plan for 2030. We investigate the patterns and processes of small-scale urban agriculture underway in this green corridor to better understand whether this type of agriculture actually intersects with, and is supported by, state plans. We frame our paper in conceptual debates around food safety and everyday governance, while supporting our analysis with data from interviews with resident gardeners and officials, as well as the mapping of urban gardens in seven wards in and alongside the green corridor. We pay attention to practices and motivations of residents who maintain small-scale vegetable and fruit plots (the most prevalent form of urban agriculture), and the challenges and constraints they face. Our work reveals the temporary and interim status of urban agriculture in Hanoi, highlighting the contradictions within Vietnam's "green city" discourse. Nonetheless, urban residents still undertake urban agriculture, negotiating or compromising with state officials, to meet their demands for fresh and safe food. [ABSTRACT FROM AUTHOR]

This paper presents the results of an assessment of the relationship between the temperature of the central part of the city of Hanoi and the type of urban surface. Landsat TM and Landsat 8 images collected from 2000 to 2019 are used to calculate the land surface temperature of the study area, as well as indices characterizing the land cover (NDVI), built-up area (NDBI), and water surface (MNDWI). The correlation coefficient between the surface temperature and the NDVI, NDBI, and MNDWI is calculated. The results show that the vegetation cover and the water surface are inversely correlated with the surface temperature, which is expressed by the negative values of the correlation coefficient. On the other hand, the built-up area has a positive correlation with the surface temperature, as is shown by the positive values of the correlation coefficient. During the entire observation period, the correlation coefficient between temperature and housing density according to the NDBI has been constantly increasing and reached its highest level in 2019. Other indices are characterized by a relative constancy of values. The results of the study show the possibility of using the NDBI to assess the housing density and can be used to rationally manage the land use of urban areas. [ABSTRACT FROM AUTHOR]

The literature is increasingly approaching the participation of households in the delivery of urban services through the lens of co-production. However, there has been no in-depth exploration of the relationship between incremental changes in the urban fabric (urban typologies and morphologies) and the forms of adaptations of co-produced water and sanitation services (WSS). The paper draws on three planned neighbourhoods in Hanoi to examine these incremental changes by considering the transformation of the neighbourhood at different scales and the consequent evolution of the sociotechnical arrangements for the delivery of water and sanitation services. By exploring forms of reconfiguration of the built environment and embedded water infrastructures, the paper outlines the possibility of an alternate reading of service co-production initiatives as incremental spatial practices, with an emphasis on the role of technology in allowing transformation processes. [ABSTRACT FROM AUTHOR]

This paper proposes a new version of the Reve's puzzle, allowing at most one violation of the "divine rule". Letting S(n) be the minimum number of moves required to solve the problem with n(≥ 1) discs, an scheme is given to find the dynamic programming equation satisfied by S(n). A closed- form expression of S(n) is derived. [ABSTRACT FROM AUTHOR]

Background: This paper analyses input from global interests in the policy process leading up to the passing of alcohol control legislation in Vietnam in 2019. The global alcohol industry now relies on growth in volume in emerging markets in middle-income countries such as Vietnam, a large, rapidly industrialising country with a youthful population and emerging middle class. The industry's role in the alcohol policy process is compared with that of global health interests. Methods: Document analysis of letters and English language media coverage was supplemented by and triangulated with data from key informants on changes in the content of draft alcohol legislation and participant observation. Results: The alcohol legislation was negotiated in the context of active engagement from the global alcohol industry and some input from global public health interests. The global alcohol industry established a partnership relationship with politicians using CSR and funded a local employee in Hanoi over the decade prior to the draft legislation being considered. Direct lobbying took place over the content of the legislation, which went through six published drafts. Trade and investment agreements provided a supportive environment and were referred to by both politicians and industry. In contrast public health resource was limited and lacked the support of a normative global policy to counter the economic imperatives. Vietnamese Ministry of Health proposals for cost effective alcohol policy were not enacted. Conclusion: Global commercial interests employed their considerable resources to engage in corporate social responsibility (CSR) and build partnerships with policy-makers over a long period, contributing significantly to an environment unsupportive of enacting effective alcohol control policy. The absence of structural support from a global health treaty on alcohol and lack of an equivalent level of long-term sustained input from global health actors contributed to the legislative outcome, which excluded proposed cost-effective policies to reduce alcohol harm. [ABSTRACT FROM AUTHOR]

Cities of the Global South constitute a wide band in terms of their integration into the global economy. For cities like Hanoi, the sustained influx of foreign direct investments has propelled them into playing increasingly important roles as manufacturing centres. Along with this new role is the influx of expatriate managers who watch overseas manufacturing subsidiaries. Our paper focuses on Korean expatriate neighbourhoods and their impacts on Hanoi. More specifically, we show how the presence of such communities has resulted in important changes in the host city, firstly in housing typology (such as the introduction of high‐rise mixed‐use complexes), and secondly, in cultural consumption. We argue that Korean privilege, cultural consumption practices, and the desire for support and solidarity within the Korean social network in Hanoi work to create new forms of city‐building knowledge, one that originates from the neighbourhoods of these new and rich settlers in the city. Such forms of knowledge subsequently go on to reshape the economic, cultural and social spaces in the globalising city. [ABSTRACT FROM AUTHOR]

Several researchers have proposed methodologies for addressing the problem of designing optimal water distribution systems. Metaheuristic approximations are studied the most due to the vast solution space. In search of reducing computational time, the Non-dominated Sorting Genetic Algorithm II (NSGA-II) has been tested with retrofitting from the Optimal Power Use Surface (OPUS) methodology. A previous study demonstrates how OPUS significantly improves the results since it seeks to reduce energy losses in the network, in order to approximate minimum-cost designs using fewer hydraulic executions. However, more research is still needed to determine applicable hydraulic criteria that allow an enhanced comprehension of optimal designs. Therefore, this paper aims to understand the characteristics of near-optimal solutions using designs from the retrofitted OPUS/NSGA-II Pareto fronts of four distinct networks (Hanoi, Balerma, Fossolo, and Modena). Moreover, fractal characteristics of the networks' energy dissipation, flow, and diameter distribution have been analyzed for this purpose. In this way, outcomes suggest that the hydraulic gradient line box dimension in optimal designs approaches a value of two, demonstrating that objects resemble a single-plane surface. These promising results propose fractal analysis as a practical design criterion due to its hydraulic significance and low computational cost. [ABSTRACT FROM AUTHOR]

This paper reports the results of the large-scale field testing of composite materials with antibacterial properties in a tropical climate. The composite materials, based on a cotton fabric with a coating of metal oxide nanoparticles (TiO2 and/or ZnO), were produced using high-power ultrasonic treatment. The antibacterial properties of the materials were studied in laboratory tests on solid and liquid nutrient media using bacteria of different taxonomic groups (Escherichia coli, Chromobacterium violaceum, Pseudomonas chlororaphis). On solid media, the coatings were able to achieve a >50% decrease in the number of bacteria. The field tests were carried out in a tropical climate, at the Climate test station "Hoa Lac" (Hanoi city, Vietnam). The composite materials demonstrated long-term antibacterial activity in the tropical climate: the number of microorganisms remained within the range of 1–3% in comparison with the control sample for the duration of the experiment (3 months). Ten of the microorganisms that most frequently occurred on the surface of the coated textiles were identified. The bacteria were harmless, while the fungi were pathogenic and contributed to fabric deterioration. Tensile strength deterioration was also studied, with the fabrics coated with metal oxides demonstrating a better preservation of their mechanical characteristics over time, (there was a 42% tensile strength decrease for the reference non-coated sample and a 21% decrease for the sample with a ZnO + CTAB coating). [ABSTRACT FROM AUTHOR]

Copyright of Urban Studies (Sage Publications, Ltd.) is the property of Sage Publications, Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Our research paper points that The majority of industrial infrastructure investment projects are in the implementation stage, the number of completed projects to construct industrial infrastructure is not much. By using qualitative analysis, inductive and synthesis methods, our study findings recommend Measures to build industrial infrastructure in Hanoi are: Improve the quality of industrial development planning and detailed planning on construction of industrial infrastructure; Focus on building infrastructure in association with environmental protection requirements of industrial parks; Improve the quality of industrial infrastructure construction works; Speeding up the construction of the infrastructure of industrial parks;Training human resources for CCNs in Hanoi; Completing policies to support the construction and development of industrial infrastructure; [ABSTRACT FROM AUTHOR]

People are increasingly using clean energy sources, contributing to environmental protection according to the general trend of the world. In the form of renewable energy, solar energy has contributed to solving current pressing problems, such as environmental pollution and air pollution, improving people's quality of life. The design of solar power projects in Vietnam is mainly based on meteorological data sources from Meteonorm and NASA. However, the accuracy assessment of two data sources compared to the actual solar power data in Vietnam is not available, so there is no basis to determine better meteorological data source quality to serve the design of rooftop solar power projects. The content of this paper analyzes the simulation results of a typical rooftop solar power station at the Electric Power University, Hanoi city based on meteorological data sources from Meteonorm and NASA. After that, the simulation results will be compared with the actual operating data of a rooftop solar power station near the Electric Power University and other real PV systems in the world. The study results showed that the amount of electricity production using the Meteonorm meteorological data was closer to the actual data than the NASA data source. Therefore, solar power projects in Vietnam should use Meteonorm data source for the design process to determine the best economic and technical efficiency for investors. [ABSTRACT FROM AUTHOR]

This paper presents a method to estimate vehicle speed automatically, including cars and motorcycles under mixed traffic conditions from video sequences acquired with stationary cameras in Hanoi City of Vietnam. The motion of the vehicle is detected and tracked along the frames of the video sequences using YOLOv4 and SORT algorithms with a custom dataset. In the method, the distance traveled by the vehicle is the length of virtual point-detectors, and the travel time of the vehicle is calculated using the movement of the centroid over the entrance and exit of virtual point-detectors (i.e., region of interest), and then the speed is also estimated based on the traveled distance and the travel time. The results of two experimental studies showed that the proposed method had small values of MAPE (within 3%), proving that the proposed method is reliable and accurate for application in real-world mixed traffic environments like Hanoi, Vietnam. [ABSTRACT FROM AUTHOR]

This paper examines the morphologies of Villages-in-the-City (ViCs) in Kunming in China and Hanoi in Vietnam, that are undergoing rapid urbanisation and urban transformation. In China, the term Chengzhongcun refers to development of rural settlements that have been included in the urban districts arising from city expansion. Meanwhile, in Vietnam, the phrase Làng trong phố is used to describe settlements in urban areas that used to be rural villages. Both types of settlements share many common characteristics linked to rural background, and to social and economic policies in these two countries. The findings illustrate that spatial transformations are generated by fundamental economic and social changes, and that the influences of land policies and roles played by local government in each country have significant impacts on the formation of the ViCs. Although the planning processes are managed though top-down systems, the diverse practices and small scale and cost-effective tactics contribute to the transitions of the ViCs. The morphological differences between ViCs development in two countries are due to differences in management modes and land use rights. The outcome of this paper contributes to the deeper understanding about similarities and differences of ViCs in the Global South. • This paper examines and compare the morphologies of Villages-in-the-City in Kunming in China and Hanoi in Vietnam. • The diverse practices and small scale tactics contribute to the transition from rural to urban live styles in both places. • The differences between ViCs developments are due to different modes of management and land use rights. [ABSTRACT FROM AUTHOR]

Introduction: Patient safety culture (PSC) is a vital component in ensuring high-quality and safe patient care. Assessment of physicians' and nurses' perceptions of existing hospital PSC is the first step to promoting PSC. This paper is aimed to assess physicians' and nurses' perceptions of PSC in 5 public general hospitals in Hanoi, Vietnam. Methods: This cross-sectional study surveyed 410 physicians and 824 nurses utilizing the validated Hospital Survey on Patient Safety Culture in an online format. Results: The composite positive physician's perception of PSC varied from 47.8 to 89.6% with the lowest composite score of patient safety for "staffing" (47.8%) and the highest composite score for "teamwork within units" (89.6%). The composite positive responses for perception among nurses varied from 51.3 to 94.2% with the lowest composite score of patient safety for "staffing" (51.3%) and the highest composite score for "teamwork within units" (94.2%). Conclusion: The mean scores for "supervisor/manager expectations"; "staffing", "management support for patient safety", "teamwork across units", "handoffs and transitions" among nurses were significantly higher than that among physicians (p< 0.05). About two-thirds of physicians and nurses reported no event in the past 12 months (62.8 and 71.7%, respectively). The nurses reported significantly higher patient grades (every good and excellent) than physicians (75% vs 67.1%, p < 0.001). Hospitals could develop and implement intervention programs to improve patient safety, including providing interventions on teamwork and communication, encouraging staff to notify incidents, and avoiding punitive responses. [ABSTRACT FROM AUTHOR]

At a time when the impacts of climate change and increasing urbanization are making risk management more complex, there is an urgent need for tools to better support risk managers. One approach increasingly used in crisis management is preventive mass evacuation. However, to implement and evaluate the effectiveness of such strategy can be complex, especially in large urban areas. Modeling approaches, and in particular agent-based models, are used to support implementation and to explore a large range of evacuation strategies, which is impossible through drills. One major limitation with simulation of traffic based on individual mobility models is their capacity to reproduce a context of mixed traffic. In this paper, we propose an agent-based model with the capacity to overcome this limitation. We simulated and compared different spatio-temporal evacuation strategies in the flood-prone landlocked area of the Phúc Xá district in Hanoi. We demonstrate that the interaction between distribution of transport modalities and evacuation strategies greatly impact evacuation outcomes. More precisely, we identified staged strategies based on the proximity to exit points that make it possible to reduce time spent on road and overall evacuation time. In addition, we simulated improved evacuation outcomes through selected modification of the road network. [ABSTRACT FROM AUTHOR]