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The history of urban green space system planning in the capital city of Hanoi, Vietnam (1886 - 2011)
Full text linkUrban green spaces have gained increasing recognition due to industrialization, modernization, and the negative impacts of climate change. This article examines the history of urban green space system planning in Vietnam’s capital city, Hanoi, focusing on its theoretical prototype and practical planning situations from an international perspective. Aiming to alleviate the crowded and residential conditions caused by the high construction density of the central urban area in Hanoi, the Vietnamese policymakers, planners and investors proposed and formulated planning versions of urban green space to improve its urban congestion and environmental issues. Using the case of urban green space system planning of Hanoi during the French modern planning influence period (1886 - 1954), the Soviet Union planning influence period (1954 - 1991), and the globalization period (1991 - 2011), this article examines urban green space system planning which authorities developed for the capital city of Hanoi in three different periods. By analyzing planning concepts, planning policy, and implementation situations of planning, this article argues that urban green space system planning aims to improve the urban environment quality and create green and leisure spaces for residents. Throughout this trajectory, urban green space planning in Vietnam has undergone continuous transformations. However, in terms of the actual construction and implementation, green space projects in Hanoi city are difficult to succeed due to the issues of urban land using policies, misconceptions arising from diverse perceptions, and the absence of long-term vision
The Survival of Rituals and Traditional Culture: Practicing United Temples in Singapore\u27s Community Planning
No full textThis paper explores the challenges and innovative approaches to preserving traditional cultural heritage with rapid urbanization, through a comparative analysis of temple management and urban planning in Singapore and coastal cities in China such as Putian and Macau. Singapore\u27s model of united temples demonstrates the potential for effectively protecting heritage within urban planning frameworks, while coastal cities in China face evolving urban landscapes and challenges in heritage preservation. The concept of "roof-top temples" emerging in Putian reflects dynamic responses to urbanization pressures, integrating traditional culture with contemporary urban functions. Community engagement and government policies play crucial roles in safeguarding cultural heritage and promoting sustainable urban development. By drawing on best practices from Singapore and coastal cities in China, pathways toward inclusive and sustainable urban development can be formulated for cities like Putian, ensuring the flourishing of rich cultural heritage amidst changing urban landscapes
The Importance of Direct Routes for Air Travel Itinerary Choices: Results from a Stated Preference Choice Experiment
Full text linkOver the past years, aviation policies are more and more focussed on sustainability rather than connectivity, putting pressure on airlines to re-design the network. For this, evaluating air travellers their preferences on direct routing compared to lay-overs is needed to make well-informed design choices. This paper examines the preferences of air travellers on direct itineraries by applying a data-driven approach. To this end, a stated preference choice experiment is developed and implemented in an online survey. The results of the latent class choice model show two types of flyers with different preferences, labelled as time sensitive and price sensitive flyers. The model outcomes indicate that both are willing to pay for direct itineraries, while time sensitive flyers are willing to pay substantially more. Other flight characteristics also play an important role in air travellers’ route choice, such as the distance to the airport, travel time, and transfer time. Travel motive, ticket price compensation by the employer, and experience with layovers drive whether air travellers belong to the time or price sensitive flyers. The distinction between time and price sensitive flyers and their preferences is expected to yield more tailored transport policies than a distinction between, for instance, business and non-business. Future research should focus on the societal impact of a reduction in direct itineraries for air travellers, using insights gained in this study
Estimation of demand models for long-distance international travel – Key determinants for Swedes’ travel abroad
Full text linkAlthough long-distance international travel contributes significantly to global emissions from the transport sector, disaggregated travel demand forecasting models on long-distance international travel are scarce. Large infrastructure investments such as high-speed rail may have a profound impact on long-distance international travel demand and thus need to be evaluated using such models. In this study, a disaggregated travel demand forecasting model is estimated using Swedish national travel survey data from 2011-2016 along with detailed supply data from European road, train, and ferry networks and a World-wide air network, aiming at forecasting Swedes’ long-distance travel abroad. Mode choice, destination choice and trip generation are modelled by traditional Nested Logit models and Multinomial Logit models. The model is segmented by purpose (private or business) and for private trips also by number of nights away. The model estimation results reveal effects of individual socio-economic attributes, level-of-service attributes, and destination characteristics. Marginal effect estimates of level-of-service attributes for train suggest that infrastructure investments in high-speed rail network may have a profound effect on demand for long-distance international travel, especially for business trips
Decay of bow thruster induced near-bed flow velocities at a vertical quay wall: A field measurement
Full text linkDuring berthing operations of large vessels, the bow thruster jet deflecting on the quay wall and the bed can lead to high flow velocities near the bed. This may scour the bed when it is left unprotected, causing instability of the adjacent quay wall. Due to the complex flow field of the reflected jet, the decay in near-bed flow velocities perpendicular to the quay wall is unknown. This results in uncertainties in the design of bed protections, especially in the required width.
In this research, the decay of the near-bed flow velocity perpendicular and parallel to the quay wall induced by a 4-channel bow thruster is studied. Field measurements have been conducted in the North Sea Port of Gent with one of the largest Dutch inland vessels. The near-bed flow velocities have been measured at multiple distances from the quay wall.
For the flow velocity measurements four main parameters have been varied: the applied bow thruster power, quay wall clearance, number of thrusters, and the lateral distance between jet axis and measurement sensors.
The highest flow velocities were measured near the quay wall, rapidly declining while moving away from the quay. Comparison of the measurement results to the Dutch and German guidelines generally leads to the conclusion that these guidelines are conservative. In addition, the dependency of the velocity on the total travelled distance by the jet as given in the Dutch method is not reflected in the measurement results. Furthermore, fundamentally different outcomes on the influence of the quay wall clearance on the near-bed flow velocity have been found.
When the measured near-bed flow velocities are used as the sole input to calculate the required bed protection, significantly smaller rock sizes and asphalt mattress thickness would be necessary to withstand the hydraulic load of the jet in comparison to current guidelines. Further studies with different vessels and direct measurement of the efflux velocity of the thrusters are recommended
Validation of an efficient two-layer non-hydrostatic wave model on a sloping foreshore
Full text linkIn the physical modelling of coastal engineering problems, use is often made of foreshores and transition slopes to obtain the desired wave conditions - both spectral parameters and wave height distribution - at a given location. Numerical wave models can be used to predict whether the target wave conditions are met for a given physical model layout and wave forcing. The XBeach non-hydrostatic two-layer model is a computationally efficient numerical model that has been validated for spectral wave parameters, but lacks validation of the simulated wave height distributions. In this work, wave flume data with high spatial density over a sloping foreshore is used to validate the ability of this numerical model to reproduce both spectral wave parameters and wave height distributions. As part of this effort, optimal settings have been derived for the wave breaking formulation used in the numerical model, resulting in recommended values for the maxbrsteep and reformsteep parameters of 0.40 and 0.20 respectively.
From the results of the validation it is concluded that the numerical model is unsuccessful in reproducing the validation tests with 5.0% wave steepness, potentially due to the higher kph numbers on the generating model boundary. Hence, using the numerical model with values of kph ≥ 2 on the model boundary is not recommended.
The XBeach non-hydrostatic two-layer model performs much better for the 1.0% and 2.5% wave steepness tests, where the spectral wave parameters are represented well. The corresponding wave height distributions are represented reasonably well up to the point that the relative water depth gets very shallow. For shallower water, the model is expected to underestimate the higher waves in the wave height distribution. Additionally, the numerical model is shown to reproduce the wave height distribution better than a commonly used analytical formulation for wave height distributions on slopes
Probabilistic Tsunami Hazard Assessment from Manila Trench to Shantou City in China
Full text linkManila Trench is an ocean trench that lies to the west of Luzon Island in the Philippines, which has the potential to generate a significant tsunami that could affect the coastal areas around it. This paper analyzes the tsunami hazard at the southern coastline of China, and more specifically at the city of Shantou. A Monte Carlo-type probabilistic tsunami hazard assessment (PTHA) with 5000 simulation runs was conducted using the tsunami propagation model COMCOT. A wide range of earthquake magnitudes were stochastically simulated in these zones, ranging from 7.0 to 9.0 in magnitude, and the peak nearshore tsunami amplitude (PNTA), for return periods of 100, 1,000 and 10,000 years, was determined by propagation simulations to be 0.15 m, 0.65 m and 1.75 m, respectively. Inundation simulations for the case study area, which considered various scenarios of sea level rise between the present day and the year 2100, were also conducted. The results indicate the severe influence that sea level rise could have on tsunami risks, which can provide valuable information for disaster risk managers and planners on how to develop adaptation pathways not only for this city but also for other points in the southeast coastline of China
Developing places for human capabilities: Understanding how social sustainability goals are governed into urban development projects
Full text linkThis dissertation develops an understanding towards governing social sustainability goals into area-based urban development projects. It draws on Amartya Sen’s Capability Approach to construct a capability-centered evaluation of how institutionalized governance processes around these projects ultimately affect people’s freedoms to do the things they value in their urban living environment. Presenting case studies from the Netherlands, Sweden and Austria, the approach adopted in this dissertation reveals the unique ways in which different individuals interpret urban social sustainability and convert spatial resources into personal capabilities. The research uncovers the governance elements and institutional conditions around urban development projects that enable or constrain resource-to-capability conversions. It shows that governing social sustainability goals into urban development projects is a balancing act between reflexive governance action on the one hand, and an institutionalization of principles, actor responsibilities, and funding provision on the other hand. Ultimately, this dissertation argues that, to steer towards urban social sustainability, urban development practices can be improved by adopting an approach that is not merely focused on spatial improvements, but takes the equal expansion of human capabilities as its point of departure
The Intelligent Built-Environment as Cyber-Physical System
Full text linkThis thesis presents an alternative approach to intelligence in the built-environment, departing from the two established yet divergent branches in the discourse: the Technical, centered around Information and Communication Technologies (ICTs), and represented by Ambient Intelligence (AmI) and Ambient Assisted Living (AAL); and the Architectural, centered around architectural / spatial experiences and considerations, and represented by Interactive Architecture and Adaptive Architecture. The promise of both AmI/AAL and IA/AA is constrained by rigid and increasingly outdated assumptions in their approaches—i.e., AmI’s / AAL’s approach to the built-environment, and IA’s / AA’s approach to ICTs. Moreover, it is impossible to combine them to yield a cohesive system due to disparity in their typical Technology Readiness Levels. That is, the sophistication of a system depends on that of its mutually complementing subsystems; and two or more subsystems may not mutually complement, sustain, and/or support one another if their levels of development do not correspond. Consequently, the presented alternative conceives the intelligent built-environment as a Cyber- Physical System. Under this approach, ICTs and Architectural considerations in conjunction instantiate intelligence fundamentally. The presented approach’s promise is illustrated via its application to a constrained use-case focused on the elderly. Twelve proof-of-concept demonstrators are developed based on key parameters pertaining to Indoor Environmental Quality and Quality of Life. While each demonstrator is presented as a discrete proof-of-concept, all build on the same core System Architecture and technological ecosystem, and are intended to be viewed as a collection of systems and services expressed within a same hypothetical environment
Contesting the Toilet: Colonial Discourses, Elite Protests, and Religious Sentiments on Public Sanitation Infrastructure in Bombay City
Full text linkPublic toilets have always been an intensely politicised site. Focusing on the colonial discourses of a ‘contaminated city’ and its implications for public health, this paper explores the politics surrounding the construction of public toilets in colonial Bombay City. The paper relies extensively on the Standing Committee and Corporation Committee debates to examine the complex dynamics of the public space, infrastructure, governance, and urban politics. Firstly, the paper traces the development of sanitation policy in the city and highlights how offensive odours, inadequate sanitary infrastructure and urban contamination were identified as the key factors in the spread of diseases at the turn of the twentieth century. Secondly, this paper delves into the protests of city elites against the construction of public toilets in their neighbourhoods, exploring how their concerns over the economic value of their land and the perception of public toilets as \u27insanitary\u27 spaces led them to utilize their social standing to influence urban planning and hinder the implementation of essential sanitation infrastructure. Finally, the paper investigates the contentious interplay between religious sentiments and the construction of public toilets in their vicinity, revealing how conflicts arising from the perception of sacrilege and religious sensitivities hindered effective sanitation infrastructure development and public health initiatives