Showing papers on "Design strategy published in 2019"

A property-oriented design strategy for high performance copper alloys via machine learning

Abstract: Traditional strategies for designing new materials with targeted property including methods such as trial and error, and experiences of domain experts, are time and cost consuming. In the present study, we propose a machine learning design system involving three features of machine learning modeling, compositional design and property prediction, which can accelerate the discovery of new materials. We demonstrate better efficiency of on a rapid compositional design of high-performance copper alloys with a targeted ultimate tensile strength of 600–950 MPa and an electrical conductivity of 50.0% international annealed copper standard. There exists a good consistency between the predicted and measured values for three alloys from literatures and two newly made alloys with designed compositions. Our results provide a new recipe to realize the property-oriented compositional design for high-performance complex alloys via machine learning.

iBioSim 3: A Tool for Model-Based Genetic Circuit Design.

Abstract: The iBioSim tool has been developed to facilitate the design of genetic circuits via a model-based design strategy. This paper illustrates the new features incorporated into the tool for DNA circuit design, design analysis, and design synthesis, all of which can be used in a workflow for the systematic construction of new genetic circuits.

The inverse design of structural color using machine learning

Abstract: Efficiently identifying optical structures with desired functionalities, referred to as inverse design, can dramatically accelerate the invention of new photonic devices, and this is especially useful in the design of large scale integrated photonic chips. Structural color with high-resolution, high-saturation, and low-loss holds great promise in image display, data storage and information security. However, the inverse design of structural color remains an open challenge, and this impedes practical application. Here, we propose an inverse design strategy for structural color using machine learning (ML) technologies. The supervised learning (SL) models are trained with the geometries and colors of dielectric arrays to capture accurate geometry-color relationships, and these are then applied to a reinforcement learning (RL) algorithm in order to find the optical structural geometries for the desired color. Our work succeeds in finding simple and accurate models to describe geometry-color relationships, which significantly improves the efficiency of the design. This strategy provides a systematic method to directly encode generic functionality into a set of structures and geometries, paving the way for the inverse design of functional photonic devices.

ABCD-Strategy: Budgeted Experimental Design for Targeted Causal Structure Discovery

Abstract: Determining the causal structure of a set of variables is critical for both scientific inquiry and decision-making. However, this is often challenging in practice due to limited interventional data. Given that randomized experiments are usually expensive to perform, we propose a general framework and theory based on optimal Bayesian experimental design to select experiments for targeted causal discovery. That is, we assume the experimenter is interested in learning some function of the unknown graph (e.g., all descendants of a target node) subject to design constraints such as limits on the number of samples and rounds of experimentation. While it is in general computationally intractable to select an optimal experimental design strategy, we provide a tractable implementation with provable guarantees on both approximation and optimization quality based on submodularity. We evaluate the efficacy of our proposed method on both synthetic and real datasets, thereby demonstrating that our method realizes considerable performance gains over baseline strategies such as random sampling.

Testing for arbitrary interference on experimentation platforms

Abstract: SummaryExperimentation platforms are essential to large modern technology companies, as they are used to carry out many randomized experiments daily. The classic assumption of no interference among users, under which the outcome for one user does not depend on the treatment assigned to other users, is rarely tenable on such platforms. Here, we introduce an experimental design strategy for testing whether this assumption holds. Our approach is in the spirit of the Durbin–Wu–Hausman test for endogeneity in econometrics, where multiple estimators return the same estimate if and only if the null hypothesis holds. The design that we introduce makes no assumptions on the interference model between units, nor on the network among the units, and has a sharp bound on the variance and an implied analytical bound on the Type I error rate. We discuss how to apply the proposed design strategy to large experimentation platforms, and we illustrate it in the context of an experiment on the LinkedIn platform.

Enacting Identities: Participatory Design as a Context for Youth to Reflect, Project, and Apply their Emerging Identities

Abstract: Participatory design is an essential design strategy for creating artifacts and experiences that reflect the voices of the population being designed for and with. The participatory design process can serve not only to research resulting artifacts but also as an empowering activity for those who participate. This paper explores how participatory design can serve as a context for young participants to enact and voice their emerging identities and reveals how different participatory design activities have unique affordances for supporting this identity enactment. Focusing on a group of 12 and 13-year-old African American girls, this paper presents a case study showing how participatory design activities served as venues for the girls to reflect characteristics of their current identities, project future identities, and apply aspects of their identities to shape materials for others. In doing so, we contribute a case study showing how participatory design allows participants to enact their identities, helping researchers gain insight into characteristics of those they are designing with and for. This paper advances our understanding of participatory design as a design approach for youth, especially as it relates to issues of broadening participation, identity, and equity.

Optimizing and Satisficing: The Interplay Between Platform Architecture and Producers' Design Strategies for Platform Performance

Abstract: Two-sided platforms are gaining increasing attention in practice and as the subject of IS and management research. We explore an assumption of research and practice: that a platform’s architecture needs to be decoupled so that producers can easily mix and match the platform’s design elements (APIs, code libraries, process models, etc.) into apps that perform well competitively, and insulate the platform from skewed outcomes and low market performance. However, in practice, complete decoupling is not just difficult but almost impossible. Based on more than two million runs of an exploratory NK model in which producers use a platform’s design space for the creation of apps, we generate several surprising insights. First, we show that tighter coupling may not necessarily be harmful depending on the producers’ design strategies and the amount of constraints placed on design elements. Second, we observe that if moderate to tightly coupled platforms with optimizing producers focused exclusively on being competitive, platform performance is lower compared to platforms with satisficing producers who put a lower priority of being competitive because of other interests. This is surprising since optimizers are better suited to cope with the inherent uncertainty of coupling. Finally, moderately coupled platforms can outperform platforms with loose coupling when constraints nudge producers into distant design moves while also isolating them from downside uncertainty. These three findings offer implications for multiple streams of literature on platform architectures.

Optimal design of steel skeletal structures using the enhanced genetic algorithm methodology

Abstract: This study concerns with the design optimization of steel skeletal structures thereby utilizing both a real-life specification provisions and ready steel profiles named hot-rolled I sections. For this purpose, the enhanced genetic algorithm methodology named EGAwMP is utilized as an optimization tool. The evolutionary search mechanism of EGAwMP is constituted on the basis of generational genetic algorithm (GGA). The exploration capacity of EGAwMP is improved in a way of dividing an entire population into sub-populations and using of a radial basis neural network for dynamically adjustment of EGAwMP’s genetic operator parameters. In order to improve the exploitation capability of EGAwMP, the proposed neural network implementation is also utilized for prediction of more accurate design variables associating with a new design strategy, design codes of which are based on the provisions of LRFD_AISC V3 specification. EGAwMP is applied to determine the real-life ready steel profiles for the optimal design of skeletal structures with 105, 200, 444, and 942 members. EGAwMP accomplishes to increase the quality degrees of optimum designations Furthermore, the importance of using the real-life steel profiles and design codes is also demonstrated. Consequently, EGAwMP is suggested as a design optimization tool for the real-life steel skeletal structures.

CAD-based identification of product low-carbon design optimization potential: a case study of low-carbon design for automotive in China

Abstract: The low-carbon design strategy that most Chinese manufacturers evaluate and improve in the product’s life cycle in the late stage of product development extends the product development cycle. This paper combines low-carbon design theory with 3D design software, in the early stage of product design, by identifying low-carbon design optimization potential, the feedback mechanism of evaluation results and design recommendations is established to guide designers’ conduct in low-carbon design in real time. Taking low-carbon design of Chinese automobile for instance, based on the life cycle carbon emission analysis of automobile products and the construction of a quantification model of the life cycle carbon emission, from the viewpoints of the structure, material, process, disassembly, and recycling of automobile products, this paper constructs the low-carbon evaluation index of automobile products; puts forward the method of identifying low-carbon design optimization potential of automobile parts, which is used to develop a low-carbon design integrated system for automobile products; and explains the workflow and theoretical realization scheme of the integrated system. Finally, taking the design process of automobile engine as an example, through the analysis results of the integrated system, it can be seen that the raw material acquisition stage of the engine has the largest carbon emission, and the carbon emission of the cylinder block is the largest. Based on the established evaluation model, the optimization suggestions are given on the structure and materials, and the feasibility of the integrated system is verified.

Articulating a strategic approach to face complexity in design projects: The role of Theory of Change

Abstract: In today’s world of global wicked problems, constraints and imperatives imposed by an external and uncertain environment render strategic action a quite complex endeavour. Since the 1990s, within community initiatives and philanthropic projects, the construct of Theory of Change has been used to address such complexity. Theory of Change can be defined as the systematic and cumulative study of the links between the activities, outcomes, and context of an intervention. The area of focus for this paper is to explore whether Theory of Change can support more strategic approaches in design. In particular, the paper examines how Theory of Change was applied to DESIGNSCAPES - a project oriented, among other things, toward offering a supporting service for all those city actors interested in using design to develop urban innovation initiatives that tackle complex issues of broad concern.

ABCD-Strategy: Budgeted Experimental Design for Targeted Causal Structure Discovery

Abstract: Determining the causal structure of a set of variables is critical for both scientific inquiry and decision-making. However, this is often challenging in practice due to limited interventional data. Given that randomized experiments are usually expensive to perform, we propose a general framework and theory based on optimal Bayesian experimental design to select experiments for targeted causal discovery. That is, we assume the experimenter is interested in learning some function of the unknown graph (e.g., all descendants of a target node) subject to design constraints such as limits on the number of samples and rounds of experimentation. While it is in general computationally intractable to select an optimal experimental design strategy, we provide a tractable implementation with provable guarantees on both approximation and optimization quality based on submodularity. We evaluate the efficacy of our proposed method on both synthetic and real datasets, thereby demonstrating that our method realizes considerable performance gains over baseline strategies such as random sampling.

Applying the Kano two-dimensional model and quality function deployment to develop sustainable planning strategies for public housing in Taiwan

Abstract: The worldwide issue of high housing prices has significantly affected the general population’s inhabitation right and their willingness to purchase homes The governments of all countries have been actively promoting public housing policies to help satisfy daily living requirements for all social classes However, many differences exist in the design requirements for public housing and typical housing design, and the lack of discussion on these differences has caused design outcomes to often fail in meeting users’ requirements This study first adopts the Kano two-dimensional quality analysis method in an attempt to define the real needs of public housing users; subsequently, based on the quality function deployment method, it transforms the design requirements into a design strategy The research findings indicate that future public housing must focus on multi-generational living arrangements, energy-efficient and barrier-free designs, flexible spaces, crime prevention, self-sufficient farming, and other such areas to satisfy the needs of different users This study practically bases its case designs on a design strategy and obtained feedback from users to understand the expectations and cognitive differences between designers and residents

Comparing sighted and blind users task performance in responsive and non-responsive web design

Abstract: This article highlights the necessity to go beyond accessibility guidelines in interactive web design, and more specifically in new web trends, as well as the importance of investigations concerning universal web design usability for blind users. In this work, we compared the task performance of blind and sighted users in responsive and non-responsive web design. The results comparing task performance in responsive and non-responsive Web sites indicate that when responsive web design involves deep structures with fewer choices and more levels, it might be considered a design strategy that does not work well for both sighted and blind user populations, showing that a reasonable criterion that should be considered is to design Web sites with good usability for blind as well as sighted users.

Impact of modularity as a circular design strategy on materials use for smart mobile devices

Abstract: There is a huge variety of modular product designs for smartphones (concept studies, prototypes, products on the market), and a similarly high variety of circular economy aspects related to these different design approaches. Modularity requires initially more material input but pays off as the consumer is embracing the possibilities of modularity. Key materials for modularity features are gold, beryllium, and neodymium, etc. On the example of smartphones modularity as a strategy for circular design is analyzed in detail. Modularity of products is a design trend, which is supposed to facilitate reparability, recyclability, and/or upgradeability. However, modularity requires some design changes. The most evident design change is the need for connectors to provide mechanical and electrical contact between individual modules. Depending on the nature and use scenario of a connector reliability, robustness, wear resistance, and non-reactive surfaces are required. The paper explains different modularity approaches for smartphones, some of these being already available in the market, others are still in a conceptual phase. Analyzing technologies for modularity leads to a group of “modularity materials,” which are essential for such circular design approaches, but at the same time are among those materials with a large environmental footprint or limited recyclability. A life cycle assessment of a modular smartphone shows a roughly 10% higher environmental life cycle impact compared with a conventional design. This needs to be compensated by reaping the circular economy benefits of a modular design, i.e., higher likeliness of getting a broken device repaired, extending the lifetime through hardware upgrades and refurbishment.

NanoCarb hyperspectral sensor: on performance optimization and analysis for greenhouse gas monitoring from a constellation of small satellites

Abstract: NanoCarb is an innovative Fourier-transform imaging spectrometer dedicated to the measurement of CO2 and CH4. Both its unusual optical principle and sampling strategy allow to reach a compact design, ideal for small satellite constellation as investigated by the European project SCARBO. The NanoCarb performance assessment as well as a proof of concept is required in this framework. We have developed a design strategy to optimize the performances. We demonstrate the potential of the concept through an estimation of the sensitivity, compliant with the space mission target. We also present a preliminary mitigation of the bias induced by water on CO2 and CH4 retrieval, illustrating the efficiency and the flexibility of the NanoCarb partial interferogram sampling technique. The presented design reaches a sub-ppm random error for CO2 and sub-10 ppb random error for CH4, considering 128 km swath and 2 by 2 km2 ground resolution. Design optimization and more systematic performances are discussed.

Reducing architecture: Doing almost nothing as a city-making strategy in 21st century architecture

Abstract: This paper discusses a contemporary design strategy to deal with urban spaces. In 21st century architecture it is possible to recognize the existence of several projects that consist in doing almost nothing, carrying out only minimal modifications to their sites of intervention. In present-day architecture, this approach is considered useful sometimes to respect the surroundings and sometimes to improve them through the smallest and tiniest actions. Doing almost nothing is a strategy that can unfold in many ways. It can mean opting for inaction and thus not modifying a place at all; or designing a temporary project intended to occupy it only for a limited period of time; or also carrying out a particularly small but permanent intervention. Depending on the circumstances, it is an approach that can help architecture protecting a place, reclaiming it or reactivating its latent qualities. This strategy can be implemented both through a single intervention on a specific place, or through a network of coordinated projects in different locations. The purpose of the paper is to present this approach in the context of 21st century urban architecture, through cases studied from the last two decades.

Early-Stage design methodology for a multirole electric propelled surface combatant ship

Abstract: Modern Navies are facing a scenario in which the technology is changing at a fast pace, deeply affecting the expected missions their ships have to cope with. Not only new weapon systems and sensors, but also new subsystems and new threats call for the design of new ships. However, integrating these new elements into an existing ship is impossible, being it not designed to support them. Likewise, adapting an existing ship design is difficult as well, being the hull form not suited either for providing the required performance level or for accommodating the increased payload. Therefore, to face the actual evolutionary trend in naval ships, a new design strategy has to be adopted. In this paper, a multi-attribute design making approach to the concept design is depicted, able to exploit the capabilities of modern Information Technology tools. As an application example, a first simplified run of the process is shown, regarding the design of a multirole destroyer.

Rethinking innovation in computational design : a theoretical framework for innovative strategies to enhance the efficiency of the ‘digital’ in architectural design

Abstract: Between the potential for ‘digital’ in architectural design that is demonstrated in a minority of architectural practices, and its marginalisation in the remaining majority, there is a need to enhance the efficiency of ‘digital’ in architectural design. The vast array of digital technologies alongside the rapid evolution of these technologies show the dynamism of the situation that requires the simultaneous and continuous re-evaluation of design theory and the continuous development of innovative design strategies in practice. Therefore, the research aims to develop a theoretical framework that will underpin the development of innovative strategies in practice and will act as a roadmap for future research towards producing a mature and comprehensible theory for computational design. In order to achieve this aim, a critical review of the literature is conducted where the potential of computational design methods is explored, the centrality of parametric design is examined and recent phenomena in computational design are classified and explained. Subsequently, a case study strategy is adopted to investigate the practical context of those phenomena. This explores the digital technologies utilised, the computational design methods applied and the factors that restrict efficient use of those technologies and methods within different practical contexts and real-life design processes and project scenarios. In order to ensure reliability and a multi-perspective investigation, the firms included as case studies are varied in terms of the location, discipline, and advancement of digital technologies. The data was collected through semi-structured interviews with architects who had a high level of experience and knowledge in computational design and hold leading positions at their firms. The data is analysed based on the computational design phenomena in order to establish new links between architectural design practice and its related theory. Based on these established links, the research concludes with a theoretical framework that identifies the criteria for selecting the right digital tool for the right purpose, and the real contexts in which those digital tools can be adapted including the purpose of this adaption. The framework also identifies different approaches for the development of experience and knowledge in practice, the problems within integrated work caused by the contradiction in mindsets and the imbalance in experience and knowledge, the permanence and temporality of the emergent roles, the levels of collaboration in architectural practice, and the potential of data in architectural design. In addition, the framework identifies aspects of complexity in architectural design and the relationship among those aspects whilst identifying the absorption forces of complexity in architectural design. Furthermore, the framework investigates the impact of the ‘digital’ on design creativity and identifies different types and purposes of practice-based research. The framework demonstrates the centrality of parametric design in developing innovative strategies by showing its potential in supporting collaborative and integrated work, driving data across different platforms and design stages, adapting tools, and supporting design creativity. In addition, a new understanding for sustainability is revealed by introducing the terms ‘sustainable processes’ and ‘recycling processes’ and investigating the role of parametric design in supporting this type of process, and its appropriateness in enabling the implementation of the ‘building seed’ concept. The research also introduces the ‘Wiki Seed Library’ as an innovative design strategy and uses the theoretical framework to evaluate its potential impact. Finally, the research provides a series of recommendations for architects in practice that offer different views, ideas and inspiration to enhancing the efficiency of the ‘digital’ in architectural design.

A hybrid approach to optimize initial design strategies for pre-sale housing projects

Abstract: The purpose of this paper is to propose a hybrid decision-making model for optimizing the initial design strategies of pre-sales housing, identifying factors affecting the initial design of housing, and developing different initial design approaches and strategies based on buyers’ preferences.,Indicators and factors in line with the local initial planning and design are created according to the design quality indicator framework. The important indicators and factors are screened out preliminarily with the fuzzy Delphi method and decision-making trial and evaluation laboratory based analytic network process. The performances of two actual cases under similar site conditions are checked with regard to the overall residential sales rate and time on the market (TOM).,The result shows that the proposed model can effectively improve the sales rate, shorten the TOM and better complies with buyer design strategy demands, and thus positively correlating to economic value.,Pre-sales make possible the customized strategy of allowing future residents to participate in the housing design process. However, buyers’ participation in the design process is highly limited, and developers usually determine their planning and initial residential design strategies based on experience and intuition. With the proposed approach, the initial residential design of a project can be effectively intervened, so that home users can truly participate in the design, and the residential construction service can be provided in a unique, but non-universal way.

A Roadmap for the Integration of Active Solar Systems into Buildings

Abstract: This paper aims to simplify the interdisciplinary design process that will be used as a design tool for the viable integration of active solar energy systems into buildings, i.e., Building-Integrated Solar Thermal Systems—BISTSs; Building-Integrated Photovoltaic Systems—BIPVSs, through the creation of a roadmap. The research also aims supplement the work of researchers who have dealt with the creation of design tools that aim to optimise a specific aspect of a building design, or their geometric forms, in order to shape energy-efficient and sustainable architectural solutions. More specifically, a prescriptive design strategy is derived from the proposed design tool. This is based on five design steps, each of which is analysed and which lead to the creation of a comprehensive design tool for siting buildings so as to optimise the integration of solar systems. The originality of this tool is based on the fact that it makes an important step in the standardisation of these studies.

Combining Brand Theory with Space and Atmosphere Theory

Abstract: Brand theory and practice have remained quite two-dimensional to this day and focus on logos, corporate design, website design, etc. As with atmospheres, it was the sales room where the brand idea was spatialised early on. This chapter discusses how to spatialise brand theory and to connect it with the place atmosphere model. Moreover, the chapter works out how the bridge between the strategy of an organisation (company, hotel, destination, etc.), its brand personality and the strategy of spatial design can be built. The brand personality shows itself in the long-term handling of the eight W questions of the brand space strategy (Who, Where, Wherein, What, Whom, Way to, What for and Why).

Planning of sport and recreational facilities informed by interdisciplinary knowledge: An attempt to make a systematic and transparent design strategy

Abstract: Purpose The purpose of this paper is to develop a design strategy that investigates the systematic use of interdisciplinary knowledge through a transparent decision-making process. The study identifies relevant design parameters that should be considered in the development of this design strategy. Design/methodology/approach The empirical data were collected through observations of the design process of two new sport facilities, meetings with sport, well-being and aging experts and through semi-structured interviews with end-users. The development of the proposed design strategy is based on a methodology with elements from “Knowledge to Action (KTA),” “Action research” and a “List of value concepts.” The rigid timetable guaranteed systematic progress, where both knowledge from the end-users and experts were incorporated throughout the decision-making process. Findings The two case studies documented results involving end-users and experts in a systematic way. In conclusion, it was apparent that the use of interdisciplinary collaboration informed the design outcome. Practical implications Based on the two cases, the following advice can be given to the architectural profession: architects should use the KTA model or similar in order to target the search for relevant interdisciplinary knowledge and ensure that relevant evidence is involved in the design process of upcoming projects regarding sport and recreation. Architects should make the design process transparent so that one can see which design decisions have been made through the design process. This must be done to ensure that there is greater coherence between vision and practice. Originality/value The study showed how architects could import knowledge, skills and values from other disciplines such as environmental psychology and active living research to improve the decision-making process of future sport and recreation projects. It was also clear that this design decision process could be made more transparent in the effort to allow the various stakeholders to take ownership of the resulting design outcomes.

Backward design as a mobile application development strategy

Abstract: Backward design is a well-established design strategy that has been used to produce educational curriculum for decades. While traditionally used to plan and create classroom-based curriculum, in this paper we explore the use of backward design as a design strategy for the development of an educational mobile application, BiblioTech™ “CityHacks: In Search of Sleep.” We discuss the process from initial conception to launch and updates, as well as plans for future research.

Interactive design of space manufacturing systems, optimality and opportunity

Abstract: Increasing competitiveness in the space market, forces the industrialists and to pursuit ways to manufacture a high quality product at a minimal cost, to reduce the risk, optimize manufacturing cost and time, the developers have promoted focus on the interactive design of the products. This research focuses on Interactive Multidisciplinary Design and Optimization of Launch Vehicle Satellite with a three-stage liquid propellant. Recently, several works have been developed in the interactive Optimization Design Strategy and multidisciplinary design optimization. In this study, a new multidisciplinary design optimization approach has been involved in system space design including new disciplines. The design strategy has been successfully applied to design problems faced at space designers. The optimizer tool developed for interactive Optimization Design Strategy based on Heuristic Algorithms (Gravitational Search Algorithm, Stochastic Fractal Search, and Search Group Algorithm) proof the highest performance in terms of quality and convergence. The results of virtual reality manufacturing tool presented in this paper are significant in the preliminary system space design which presents an effective approach of development by reducing the cost and the time of analysis and that tool could help decision-makers to understand better the range of possibilities that confront them.

Weaving Architectural Façades: Exploring algorithmic stripe-based design patterns

Abstract: With the recent technological developments, particularly, the integration of computational design approaches in architecture, the traditional art techniques became increasingly important in the field. This includes weaving techniques, which have a promising application in architectural screens and facade designs. Nevertheless, the adoption of weaving as a design strategy still has many unexplored areas, particularly those related to Algorithmic Design (AD). This paper addresses the creation of weave-based facade patterns by presenting a Generative System (GS) that aids architects that intend to use AD in the design of facades inspired on traditional weaving techniques. This GS proves to reduce the time and effort spent with the programming task, while supporting the exploration of a wider solution space. Moreover, in addition to enabling the integration of user-generated weaving patterns, the GS also provides rationalization algorithms to assess the construction feasibility of the obtained solutions.

Indoor lighting optimization: a comparative study between grid search optimization and particle swarm optimization

Abstract: Design of an indoor lighting system involves, in general, a number of design parameters, viz. maintained average illuminance, uniformity of illuminance, unified glare rating, lighting power density. These design parameters are mutually conflicting and at the same time constrained because recommended value of each of the design parameter is to be satisfied simultaneously by adjusting design variables which are also bounded by upper and lower limits. An indoor lighting design problem involves a small number of design variables, such as spacing between adjacent luminaires, mounting height of luminaires, and the objective function is non-differentiable and thus suitable to apply both the grid search optimization and particle swarm optimization methods. This study compares the performance of these two methods to find out optimized design solutions for a set of indoor lighting design strategies, usually come across by lighting designers. An objective function is formulated by assigning weights to the design parameters, where a specific design strategy can be selected by adjusting the weights. This study reveals that the performance of PSO is significantly better to meet the qualitative aspect of lighting ambiance; however, the improvement is not significant than the grid search method when a design strategy puts stress upon the quantitative aspect of lighting.