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In this case study, we compared the gross composition and fatty acid (FA) composition of milk from cows milked once a day (OAD) and twice a day (TAD) at different stages of lactation in real farm conditions with no control on feed. Seventy-two cows from a OAD milking herd and 181 cows from a TAD milking herd were sampled in early, mid and late lactation. Calibration equations were developed to enable the prediction of proportions of individual FAs using mid-infrared (MIR) spectroscopy. Cows milked OAD produced 25% lower daily milk yield (MY) compared to cows milked TAD. Percentages of fat and protein were 21% and 9% higher in cows milked OAD compared to cows milked TAD, respectively. The proportion of saturated fatty acids (SFA) (molecules with unbranched hydrocarbon chains and all single bonds) was significantly lower, while the proportions of de novo synthesised FAs from C8:0 to C14:0 were significantly higher, in cows milked OAD compared to cows milked TAD. OAD milking improved the energy balance of cows, which led to higher proportions of de novo synthesised FAs and lower proportions of long-chain fatty acids (16:0 and above). The proportion of SFA was significantly higher in mid lactation (ML) compared to early lactation (EL) and late lactation (LL) in cows milked OAD and TAD. In EL, the proportions of C4:0 to C12:0 FAs in cows milked OAD were significantly higher compared to the cows milked TAD due to the improved energy status of cows milked OAD. Understanding the proportions of individual FAs in cows milked OAD and TAD will enable further studies on milk fat characteristics and on butter hardness and coagulation properties of milk.

In practice, most planners do not make significant use of planning support systems. Although extensive research has been conducted, the focus tends to be on supporting individual tasks, and the outcomes are often the development of new stand-alone tools that are difficult to integrate into existing workflows. The knowledge contribution in this article focuses on developing a novel spatial decision support framework focusing on the workflows and tool-chains that span across different teams with varying skill sets and objectives, within an organisation. In the proposed framework, the core decision-making process uses a set of decision parameters that are combined using a weighted decision tree. The framework is evaluated by developing and testing a workflow and GIS tool-chain for a real-world case study of land suitability and mixed-use potentiality analysis.

Digital building modelling faces issues related to inconsistent integration/interoperability, in particular for a BIM GIS convergence. A consistent data conversion approach should consider semantic...

This research integrates cooling systems as a variable in the multi-objective optimisation of building form and envelope design in the early design stages. The integration is achieved by 1) using a simplified calculation that requires minimal form, envelope and systems data for calculating the energy consumption of the cooling systems, and 2) optimising the cooling energy consumption by selecting the most efficient system automatically. The benefit of the integration is demonstrated in a case study using daylight as a second, potentially conflicting objective. The optimisation result is manually clustered and compared. The comparison reveals that the use of an efficient cooling system has the potential to achieve better trade-offs between the two conflicting objectives. These trade-offs are valuable information for designing the building form and envelope in the early design stages.

For sustainable building design, performance-based optimization incorporating parametric modelling and evolutionary optimization can allow architects to leverage building massing design to improve energy performance. However, two key challenges make such applications of performance-based optimization difficult in practice. First, due to the parametric modelling approaches, the topological variability in the building massing variants is often very limited. This, in turn, limits the scope for the optimization process to discover high-performing solutions. Second, for architects, the process of creating parametric models capable of generating the necessary topological variability is complex and time-consuming, thereby significantly disrupting the design processes. To address these two challenges, this paper presents a parametric massing algorithm based on the subtractive form generation principle. The algorithm can generate diverse building massings with significant topological variability by removing different parts from a predefined volume. Additionally, the algorithm can be applied to different building massing design scenarios without additional parametric modelling being required. Hence, using the algorithm can help architects achieve an explorative performance-based optimization for building massing design while streamlining the overall design process. Two case studies of daylighting performance optimizations are presented, which demonstrate that the algorithm can enhance the exploration of the potential in building massing design for energy performance improvements.

Differences in the scope and intent of the contrasting IFC and CityGML data formats entail that converting the former to the latter results in loss of information. However, for some use cases it is beneficial to keep also particular information from IFC that is not native to CityGML, and achieving that requires mechanisms such as the CityGML Application Domain Extension (ADE). We develop an ADE to support retaining relevant information from IFC. Besides being driven by the particular source of the input data (IFC), this multi-purpose ADE is shaped after a discovery process that involved examining potentially applicable use cases in Singapore, doubling as an extension that is adapted to a set of use cases and the local geographic context. We implement the conceptual work by generating an enriched dataset (with an automatic conversion from IFC to CityGML), visualising it, and discuss its added value in a use case.

Evolutionary design allows complex design search spaces to be explored, potentially leading to the discovery of novel design alternatives.

Walkability is often regarded as a key resilience and liveability indicator for urban neighbourhoods and the city (Robertson and Hachem-Vermette 2017). Singapore often tops the rankings as the most liveable city in Asia, especially due to its easy access to public amenities (The Strait Times 2018). However, active mobility, including walking and cycling, only account for a minority of all ridership in the city (CLC and ULI 2017). This raises two key questions: 1) what factors hinder walkability in Singapore and 2) how can the built environment be improved to promote active mobility. This study argues that the lack of detailed urban design guidelines impedes the creation of pedestrian-friendly environments, especially for public housing neighbourhoods that form the main urban landscape of Singapore. It then explores the possibility of using Form-based Codes (FBC) to improve walkability for the public housing neighbourhoods. Such codes have been repeatedly proved in the Western cities as an effective design guideline to regulate the built environment and create walkable neighbourhoods (Hansen 2014). However, they have never been applied in the Asian context. Methodologically, this research first diagnosed main problems pertaining to poor walkability of public housing neighbourhoods based on a comprehensive review of existing studies and site survey. The problems then provide a lens to assess the literature and the best practices of FBC, identifying the strengths and limitations of applying such codes to Singapore’s public housing neighbourhoods. On this basis, a framework and key principles for developing new FBC were derived, and new design guidelines were tested using two case studies. This study for the first time explored applying FBC to high-density tropical cities in Asia. The research findings indicate that the FBC principles and methods for improving neighbourhood walkability are potentially useful for enhancing liveability and resilience of other similar urban environments.

The optimisation of semi-transparent building integrated photovoltaic facades can be challenging when attempting to find an overall balance performance between conflicting performance criteria. This paper presents a three-phase design optimisation method that maximises overall electricity savings generated by these types of facades by simulating the combined impact of electricity generation, cooling load, and daylight autonomy. Two demonstrations are performed, with the difference being that the second demonstration uses an enhanced model for calculating daylight savings that takes into account the use of blinds to counteract glare. For both demonstrations, the three-phase optimisation method significantly reduces optimisation run times. Comparing the design variants evolved by the two demonstrations, the use of the enhanced daylight savings model results in a total electricity savings that is more accurate but in terms of visual differentiation, the difference between the optimized design variants is relatively small.

This study is an exploration of the relationship between density, built form typologies and their respective environmental qualities. A methodology was proposed to facilitate the investigation of the environmental implications of density and the search of alternative built form typologies with good environmental performance potential that can be further explored in the context of high density development. The utility of the proposed methodology was demonstrated through a preliminary case study on several representative urban blocks and residential precincts by focusing on one environmental performance variable, i.e. exposure to the sky. The results indicate that the existing environmental performances as indicated by facade and ground level sky exposure vary across the representative built form typologies under study. Moreover, the performances of the cases selected react differently to variation of density due to increase of building height. The differences in existing performances and sensitivities to density variation between the cases investigated in relation to their built form are discussed. The findings suggest that, when targeting at higher development density, the proposed methodology can assist planners and urban designers in their search for alternative urban block typologies that provide different spatial configurations with equally good or even better environmental performance.

This work arises within the framework of the introduction of renewable energies at Amsterdam Airport Schiphol (AAS) and the focus is on the technical feasibility of a solar energy system (SES) on ground level. The flight safety must always be guaranteed if solar panels are implemented on AAS. The radiation reflection of solar panels according to the optical effect towards the pilot of an airplane and the line of sight of the Air traffic tower has been studied. Also the constraints for installing an "object" at the Airport have to be taken into account. This should lead to an overall impression of the potential of solar panels that can be orientated on ground level. A complete model of a solar energy system is designed: tilt angle, type of solar panels, equipment (DC/AC inverter), a cable system as well as the way the design can be implemented in the electricity infrastructure of AAS. Power Quality (PQ) and the effects of implementing a SES will be discussed: disturbances have to be minimized

This paper describes a comprehensive framework for generative evolutionary design. The key problem that is identified is generating alternative designs with an appropriate level of variability. Within the proposed framework, the design process is split into two phases: in the first phase, the design team develops and encodes the essential and identifiable character of the designs to be generated and evolved; in the second phase, the design team uses an evolutionary system to generate and evolve designs that embody this character. This approach allows design variability to be carefully controlled. In order to verify the feasibility of the proposed framework, a generative process capable of generating controlled variability is implemented and demonstrated.