Existing Case Studies Research Articles

Bridging the Gap Between Probabilistic Model Checking and Probabilistic Planning: Survey, Compilations, and Empirical Comparison

Markov decision processes are of major interest in the planning community as well as in the model checking community. But in spite of the similarity in the considered formal models, the development of new techniques and methods happened largely independently in both communities. This work is intended as a beginning to unite the two research branches. We consider goal-reachability analysis as a common basis between both communities. The core of this paper is the translation from Jani, an overarching input language for quantitative model checkers, into the probabilistic planning domain definition language (PPDDL), and vice versa from PPDDL into Jani. These translations allow the creation of an overarching benchmark collection, including existing case studies from the model checking community, as well as benchmarks from the international probabilistic planning competitions (IPPC). We use this benchmark set as a basis for an extensive empirical comparison of various approaches from the model checking community, variants of value iteration, and MDP heuristic search algorithms developed by the AI planning community. On a per benchmark domain basis, techniques from one community can achieve state-ofthe-art performance in benchmarks of the other community. Across all benchmark domains of one community, the performance comparison is however in favor of the solvers and algorithms of that particular community. Reasons are the design of the benchmarks, as well as tool-related limitations. Our translation methods and benchmark collection foster crossfertilization between both communities, pointing out specific opportunities for widening the scope of solvers to different kinds of models, as well as for exchanging and adopting algorithms across communities.

Sustainable Business Models: Literature Review of Main Contributions and Themes

Literature on sustainable business models (SBM) has recently emerged and is rapidly expanding. This promising research field is aimed at intersecting traditional business model approaches with corporate sustainability. Most of the research to date has focused on existing case studies or examples of sustainability innovations in business models or on the use of frameworks and tools to categorise or design SBMs or suggest the stages of this innovative process towards sustainability. This article presents an integrative literature review aimed at describing the objective aspects of the SBM literature such as its temporal, industrial, geographical and methodological factors. As well as this descriptive analysis, the paper categorises the SBM literature in terms of its main purposes and themes. This categorisation is aimed at synthesising the main contributions of the SBM literature and to highlight gaps to suggest possible further developments. Despite presenting different perspectives on value (proposition, creation, delivery and capture), the current research on SBM has failed to take a holistic approach towards sustainable value measurement and representation in its models and frameworks.

Using ecosystem service assessments to support participatory marine spatial planning

With growing interest in ocean uses for sustainable economic development, there is an increasing need for cross-sectoral marine spatial planning to balance different resource uses and conservation requirements. Ecosystem service assessments can provide the evidence to inform marine spatial planning decisions. Existing case studies suggest that these assessments can also have positive effects on the engagement of marine stakeholders in management and planning processes. Stakeholder engagement is a central element in marine spatial planning and other area-based management approaches. However, in a marine context, engagement is often difficult due to the lack of clear boundaries in the ocean, traditionally sectoral marine management and limited understanding of marine ecosystems. The study presented here investigated ecosystem service assessments as a tool for improving marine stakeholder engagement. Stakeholder experiences with ecosystem service assessments in six marine management and planning case studies were analysed to identify why, how and under what conditions ecosystem service assessments can support effective engagement. The findings show that under the right conditions, ecosystem service assessments can provide an inclusive and integrative platform for engagement, enable a better understanding of marine ecosystems, human-ecosystem interactions and management contexts, and support better stakeholder relationships. Stakeholder participation also improves the evidence base for ecosystem service assessments. Thus, involving stakeholders in ecosystem service assessments can improve marine spatial planning decisions and lead to better management and conservation outcomes for the ocean.

Food and Nationalism: Gastronationalism Revisited

AbstractThis article reviews recent developments in scholarship on gastronationalism, or more broadly, food and nationalism. It finds while the concept of gastronationalismper sehas not been rigorously developed, scholarship of food and nationalism in general has been developing fast. A major development in the study of gastronationalism is the introduction of the everyday nationhood/banal nationalism perspective, which in turn diverts the focus away from the state’s intervention, a point emphasized by Michaela DeSoucey. The review of the field suggests that a renewed focus on the role of food in the interaction between state actors and international organizations would further refine the concept of gastronationalism. As for the study of food and nationalism, efforts to integrate findings from existing case studies to produce an overall understanding of society are needed.

Biogas from Anaerobic Digestion: Power Generation or Biomethane Production?

Biogas is a fuel obtained from organic waste fermentation and can be an interesting solution for producing electric energy, heat and fuel. Recently, many European countries have incentivized the production of biomethane to be injected into natural gas grids or compressed and used as biofuel in vehicles. The introduction of an upgrading unit into an existing anaerobic digestion plant to convert biogas to biomethane may have a strong impact on the overall energy balance of the systems. The amount of biomethane produced may be optimized from several points of view (i.e., energy, environmental and economic). In this paper, the mass and energy fluxes of an anaerobic digestion plant were analyzed as a function of the biogas percentage sent to the upgrading system and the amount of biomethane produced. A numerical model of an anaerobic digestion plant was developed by considering an existing case study. The mass and energy balance of the digesters, cogeneration unit, upgrading system and auxiliary boiler were estimated when the amount of produced biomethane was varied. An internal combustion engine was adopted as the cogeneration unit and a CO2 absorption system was assumed for biogas upgrading. Results demonstrated that the energy balance of the plant is strictly dependent on the biomethane production and that an excess of biomethane production makes the plant totally dependent on external energy sources. As for the environmental impact, an optimal level of biomethane production exists that minimizes the emissions of equivalent CO2. However, high biomethane subsides can encourage plant managers to increase biomethane production and thus reduce CO2 savings.

Optimal sizing of Battery Energy Storage Systems for dynamic frequency control in an islanded microgrid: A case study of Flinders Island, Australia

Challenging frequency control issues, such as the reliability and security of the power system, arise when increasing penetration levels of inverter-interfaced generation are imposed. As a result of the displacement of convention generation in favour of renewable energy sources, the reduction of frequency response capabilities can be seen. A promising method of overcoming the aforementioned challenges is to utilise Battery Energy Storage Systems (BESS), which provides frequency support by injecting instantaneous power to the grid and back up the conventional generation systems. However, large battery systems increase the cost while inadequate battery capacities result in poor performance. This paper, therefore, proposes an approach for finding the optimum BESS size for an islanded microgrid power system. The determination of the optimum BESS size is based on an existing case study, under which the most severe contingencies of generation loss and load loss have been accounted for, as well as different levels of penetration of renewable energy sources. As a result of using meta-heuristic optimization (Grey Wolf Optimization), the constraint optimization problem has been identified as BESS sizing. Through the use of real-time simulation DIgSILENT PowerFactory software, estimated BESS size can be applied to a standalone microgrid to test the frequency of support capabilities. The simulation has made it apparent that through the selection of the optimum BESS size, the system frequency response is not only mitigated, but improved.

SewerSedFoam: A Model for Free Surface Flow, Sediment Transport, and Deposited Bed Morphology in Sewers

This paper aims to bridge the gap in the detailed modelling of flow and sediment process interactions in sewers through the development of a computational fluid dynamics (CFD) model. It draws on previous models developed for surface water sediment transport in the OpenFOAM CFD framework and builds on them to improve their suitability for sewer sediment processes. Three distinct sediment processes, suspended sediment transport, bedload transport, and deposited bed morphology, are incorporated into a free surface flow solver, interFoam. This sewer sediment model, called SewerSedFoam, models the impacts of sediment deposition and erosion on flow velocity by using dynamic mesh deformation to capture the movement of the deposited bed and its morphology. Further, three sediment classes, two suspended and one bedload sediment, can be modelled along with some bed stabilization and consolidation effects during deposition and erosion, respectively. The functionality of the overall model in modelling sewer sediment deposition and erosion is promising, although the validation of a large magnitude sediment erosion event has been limited by the availability of granular data in existing case studies.

Clean Energy and Household Remittances in Bangladesh: Evidence from a Natural Experiment

Using a natural experiment of a rainfall-driven remittances, I provide experimental measures of how remittances affect rural household’s choice of cylinder gas (LPG) as a cooking fuel over other alternative fuels in southern Bangladesh. Household choice of LPG and remittances are jointly related; therefore, I use the instrumental variable probit (IV-Probit) approach. The treatment of remittances is randomly assigned to households who suffered losses due to a natural shock from the cyclone-Roanu enabling the instrument – exogenous variation in rainfall interacted with cyclone-affected migrant household’s distance to the local weather stations – to identify the average treatment effect for the treatment group (cyclone-affected remittances recipient households). I find that an exogenous increase in remittances by 1,000 Taka causes the probability of using LPG to rise by 1%. In terms of percentage change, the implied elasticity shows that a 10% increase in remittances income can raise the probability of using LPG by 2%. I also find the impact of remittances is conditional on household’s health expenditures. In particular, controlling for the household’s health expenditures interacted with the provision for clean water and sanitary toilet in the dwelling, the marginal effects of remittances get stronger, i.e. households are more likely to use LPG as cooking fuel. These findings counter some existing case studies and views of many policy makers that economic factors are less significant in promoting cleaner energy for the household. The results of the paper are robust to potential violations of the exclusion restriction, to alternative specifications and instruments, and possible omitted variable bias.

Functional urban area delineations of cities on the Chinese mainland using massive Didi ride-hailing records

The problem associated with a city's administrative boundary being “under-” or “over-bounded” has become a global phenomenon. A city's administrative boundary city does not effectively represent the actual size and impact of its labor force and economic activity. While many existing case studies have investigated the functional urban areas of single cities, the problem of how to delineate urban areas in geographic space relating to large bodies of cities or at the scale of an entire country has not been investigated. This study proposed a method for FUA identification that relies on ride-hailing big data. In this study, over 43 million anonymized 2016 car-hailing records were collected from Didi Chuxing, the largest car-hailing online platform in the world (to the best of our knowledge). A core-periphery approach is then proposed that uses nationwide and fine-grained trips to understand functional urban areas in Mainland China. This study examined 4456 out of all 39,007 townships in an attempt to provide a new method for the definition of urban functional areas in Chinese Mainland. In addition, four types of cities are identified using a comparison of functional urban areas with their administrative limits, and a further evaluation is conducted using 23 Chinese urban agglomerations. With the rapidly increasing use of internet-based ride-hailing services, such as Didi, Grab, Lyft, and Uber, globally, this study provides a practical benchmark for the delineation of functional urban areas at larger scales.

A comprehensive review of industrial symbiosis

Abstract Industrial symbiosis, which allows entities and companies that traditionally be separated, to cooperate among them in the sharing of resources, contributes to the increase of sustainability with environmental, economic and social benefits. Examples of industrial symbiosis have grown over the years with increasing geographic dispersion. Thus, through a comprehensive review of previous studies, this work aims to trace the trend of industrial symbiosis research and to map the existing case studies around the world, with a critical analysis of its impact. The analysis of the 584 selected publications allowed tracing the evolution of these according to their content and the type of article, as well as its distribution by journals. Based on the literature review, the main lines for research in industrial symbiosis are assessed, as well as an updated study of the published case studies is provided with emphasis on the location, type of industry and employed methodologies. Several challenges are then identified for future research. The results reveal the number of articles on industrial symbiosis has greatly increased since 2007 and China is the country with the largest number of publications and cases of industrial symbiosis, followed by the United States. The methods for quantifying impacts and analysing industrial symbiosis networks were the most widely used. The analysis of the published case studies allowed an overview of the industrial symbiosis in the world and showed that the potential for application is enormous, both in developed countries and in countries with developing economies, and although the most present economic activities in the synergies are associated with the manufacturing sector, the possibilities of industrial symbiosis are not restricted to these activities nor to the number of entities involved. The symbioses between industry and the surrounding community also have great potential for development with numerous advantages for both parties.

Analyzing and Improving Natural Daylight in Educational Buildings Using Skylights, Victoria International School of Sharjah as a Case Study

Due to the great importance of natural daylight in interior spaces, architects keep experimenting different techniques to achieve a good luminous environment. One of the techniques used in building design is the skylight. This study focuses on the impact of the skylight on internal spaces in schools with regards to daylight factor, glare, and cooling loads. Thirteen simulation cases, including the existing case, were simulated and analyzed using several software packages such as Revit, Ecotect and Radiance. The thirteen cases are categorized into three main groups: A, B, and C. Each category has set some fixed parameters in order to reach an optimum design compared with the existing case. After conducting the simulation and analysis, the sub-cases of Group-A failed to achieve a good luminous environment and therefore the results were rejected due to the large increment in cooling load. On the other hand, the sub-cases of Group-B showed considerable improvement in the cooling loads, but some of these cases had caused glare in the space. The sub-cases of Group-C were better than of those in Group-B. Herein, some of the results of this study were satisfactory compared with the existing case study. However, one of the cases in Group-B had the optimum case among the examined cases where all the results are within the accepted range.

Design adaptability as a tool for achieving affordable housing in developing economies

Provision of affordable Housing is a basic human need, and in a developing economy such as Nigeria, the government is continuously seeking innovative means of tackling the challenge of housing deficit. The growing population coupled with the lack of adequate housing has necessitated the need for a strategy by architects and designers to proffer solutions that will complement government housing policies. This study aims to propose adaptable design strategies in the provision of affordable mass housing in a developing economy like Nigeria. To achieve that, the following objectives were pursued: to propose strategies for land-use efficiency, to recommend guidelines for flexibility in design and to incorporate end users’ opinion in the design of mass housing schemes. The study adopted the qualitative research method through the review of existing case studies. Among the recommendations made was proposing guidelines on adaptable design that will aid architects and designers in the design of affordable mass housing schemes.

The Impact of Air Well Geometry in a Malaysian Single Storey Terraced House

In Malaysia, terraced housing hardly provides thermal comfort to the occupants. More often than not, mechanical cooling, which is an energy consuming component, contributes to outdoor heat dissipation that leads to an urban heat island effect. Alternatively, encouraging natural ventilation can eliminate heat from the indoor environment. Unfortunately, with static outdoor air conditioning and lack of windows in terraced houses, the conventional ventilation technique does not work well, even for houses with an air well. Hence, this research investigated ways to maximize natural ventilation in terraced housing by exploring the air well configurations. By adopting an existing single storey terraced house with an air well, located in Kuching, Sarawak, the existing indoor environmental conditions and thermal performance were investigated and monitored using scientific equipment, namely HOBO U12 air temperature and air humidity, the HOBO U12 anemometer and the Delta Ohm HD32.3 Wet Bulb Globe Temperature meter. For this parametric study, the DesignBuilder software was utilized. The field study illustrated that there is a need to improve indoor thermal comfort. Thus, the study further proposes improvement strategies to the existing case study house. The proposition was to turn the existing air well into a solar chimney taking into account advantages of constant and available solar radiation for stack ventilation. The results suggest that the enhanced air well was able to improve the indoor room air velocity and reduce air temperature. The enhanced air well with 3.5 m height, 1.0 m air gap width, 2.0 m length was able to induce higher air velocity. During the highest air temperature hour, the indoor air velocity in existing test room increased from 0.02 m/s in the existing condition to 0.29 m/s in the hottest day with 2.06 °C air temperature reduction. The findings revealed that the proposed air well could enhance the thermal and ventilation performance under the Malaysia tropical climate.

SUSTAINABLE INFRASTRUCTURE PROJECT SELECTION BY A NEW GROUP DECISION-MAKING FRAMEWORK INTRODUCING MORAS METHOD IN AN INTERVAL TYPE 2 FUZZY ENVIRONMENT

Project management is a process that is involved with making important decisions under uncertainty. In project management often the existing data is limited and vague. Sustainable project selection has a multi-criteria evaluation nature which calls for attending to various often conflicting factors under vagueness. To deal with sustainable project selection several important factors should be properly considered. In this paper, in order to provide a new multi-criteria project selection method, a novel last aggregation method is presented. This method has several main novelties. First, to address uncertainty interval type 2 fuzzy sets (IT2FSs) are used. Second, the importance of criteria is investigated by using IT2F entropy. Third, a novel index for decision making is presented that has the merits of ratio system in MOORA and COPRAS, named MORAS. Fourth, the weights of decision makers are computed according to the obtained judgments and the weights are employed to aggregate the results. Fifth, the defuzzification is carried out in the last step of the process by means of a new IT2F ranking method. To present the applicability of the method, it is used in an existing case study in the literature and the outcomes are presented.

Underground Cities : Sustainable Urbanism of the Future

Cities across the world are the main contributors to climate change but at the same time they are also the most vulnerable to its consequences. Some of the disastrous impacts of climate change include extreme weather events, periods of extreme heat and cold, high precipitation, floods, strong cyclones and storms. There is a need for urban design guidelines to effectively address the issues of climate chanbe and increase the resilience of cities. One way to adapt to this is through engineered infrastructure. Today nearly 70% of the world live in urban areas and in the next 20 years two billion more people are expected to move to the cities. With increasing urban densification land and buildable areas are going to become increasingly scarce. One possible solution is to build downwards instead of upwards. Underground areas are less susceptible to external influences and have the ability to better withstand natural catastrophes and hence can be sustainable solution for an unpredictable future. This paper will analyze the viability of underground cities through examples from history and existing case studies along with new upcoming proposals and probe how using underground spaces can increase the resilience of future cities

VERTICAL TURF FOR GREEN FAÇADES: A VERTICAL GREENERY MODULAR SYSTEM INTEGRATED TO THE BUILDING ENVELOPE

ABSTRACT Research has shown the environmental benefits of green envelopes, as well as performance in terms of energy efficiency. To date, there is no analysis of the economic sustainability of these systems, which has allowed the realization of a few, albeit very well known, examples. The research has identified a green modular system integrated into the building envelope, designed to facilitate installation and maintenance, with competitive performance compared to other existing solutions; a system that wants to improve performance and flexibility of vertical applications, experimented on buildings, on the market, and able to adapt, above all, to the needs of the building process. It is important to distinguish architectural aesthetic requirements from those of the building process; the former aim to have an authentic vertical garden, with different kinds of plants where nature dictates the rules, the latter aims to achieve the economic sustainability of vertical greenery systems. This paper provides an analysis of a technique based on the installation of plant bearing modular panels with turf on substructures also provided with a micro-irrigation system, which allows the construction of a modular coating, characterized by reduced thickness, that can also be integrated with other materials; installation is quick and simple, since the panel comes perfectly planted on site. In addition to that it allows, from a botanical point of view, resorting to types of grass selected with a view to climate, exposure, environmental adaptability, color and shape. A comparative analysis of this green façade is also presented compared to other existing case studies, from a constructive and managerial point of view, highlighting both its economic and architectural advantages.

Robust Regression Models for Load Forecasting

Electric load forecasting has been extensively studied during the past century. While many models and their variants have been proposed and tested in load forecasting literature, most of the existing case studies have been conducted using the data collected under normal operating conditions. A recent case study shows that four representative load forecasting models easily fail under data integrity attacks. To address this challenge, we propose three robust load forecasting models including two variants of the iteratively re-weighted least squares regression models and an $L_{1}$ regression model. Numerical experiments indicate the dominating performance of the three proposed robust regression models, especially $L_{1}$ regression, compared to other representative load forecasting models.

Green leases and green leasing in theory and in practice: a state of the art review

PurposeThis paper aims to identify the state of the art in Green Leases and Green Leasing in theory and practice, while also identifying how the roles and motivations of the stakeholders of “owner/landlord”, “lessee” and “facilities management” are different in a building that uses Green Leasing and Green Leases, as opposed to the one without.Design/methodology/approachThrough existing literature and existing case studies from 1995 to the present day, this paper will identify the state of the art of Green Leases and Green Leasing and the extent to which literature-based discussions have played out in their practical application in the real estate sector. The roles of key stakeholders will be analysed and then compared to the interactions and roles identified in a theoretical model that describes the same stakeholders but from a more traditional stakeholder perspective. This will be achieved through using literature from journal papers mostly from the disciplines of built environment, facilities management, finance, investment, law, management and real estate.FindingsThe literature and case studies found in literature demonstrate a gradual move towards advancing Green Lease adoption and development. While the roles of key stakeholders do see a change in Green Leased buildings in terms of, for example, changing competencies for facilities managers (FMs) and more user engagement with their buildings sustainability, the literature indicated most of the changes are realised through a strengthening of existing interactions already evident in buildings without a Green Lease or Green Leasing.Originality/valueThis paper provides a state of the art review on the development of Green Leasing and Green Leases in theory and practice from a stakeholder perspective. It provides possibility to expand further on the changing roles of these stakeholders in Green buildings, which in turn could also positively affect the further development of Green Leases themselves, as well as sustainable certification methodologies such as Europe’s leading certification “Building Research Establishment Environmental Assessment Method” (BREEAM).

Introduction To Case Study Development And Use For Engaged Learning

Location: JC Room B Case studies can be a powerful and effective means by which to engage students through the process of learning towards a goal or goals. Case studies provide an instructional method that further allows students to incorporate material from different parts of a course into a practical application. For some disciplines, there a large repository of cases that teachers can use. However, sometimes they are not ideal for the specific objectives of a course or, in the case of some disciplines, there is a dearth of existing case studies. The development of case studies for a course allows the teacher to focus and align material with the needs and experiences of his/her/their students, and utilization of case studies that rely on freely accessible material reduce barriers to access. Case studies in the classroom can be adapted in ways that are useful in Active Learning Classrooms or take advantage of technology. The objectives of this proposed workshop are to provide teachers with foundational knowledge about the development and use of different types of case studies in the classroom and to provide participants with an opportunity apply this knowledge to their own material. The session is suitable for teachers of undergraduate and graduate students for in-person or on-line formats that are new to developing case studies. The proposed workshop will be divided into four components: 1) theoretical foundations; 2) application; 3) discussion; and, 4) implementation. In the theoretical foundations component, the facilitator will provide an overview of different types of case studies and research-backed information about when and for whom they are most effective. Participants will have the opportunity to ask questions and the facilitator will be lead a discussion with examples. In the application stage, participants will have a period of time for independent work, following a guided worksheet, to develop an outline and strategy for developing a case study for their own course. In the discussion stage, participants will work in pairs or small groups to share their ideas and provide peer feedback. In the implementation component, participants will return to the full group to hear about tips and tricks for utilizing Blackboard to move cases into an on-line format, which can be useful for assignments or in the instruction of hybrid or fully on-line courses. As the end of the session, participants will leave with an idea and plan for incorporating a case study into one of their courses and know where they can seek additional information and resources for developing and implementing case studies. The proposed facilitator for the session has participated in case study development workshops, completed on-line course development certification, and recently re-designed GCH 762 Environmental Epidemiology with newly developed case studies to target student learning towards specific skill development and knowledge utilization. The workshop will draw upon these experiences and provide participants with theoretical foundation and practical application towards their own teaching.

Evaluating the electricity saving potential of electrochromic glazing for cooling and lighting at the scale of the Swiss non-residential national building stock using a Monte Carlo model

Novel electrochromic glazing technology has been identified as an emerging option for reducing cooling and lighting electricity demand. As this technology is particularly promising for office building we assess the related technical energy saving potential in case of nation-wide implementation in Swiss office buildings. A Monte Carlo model of Swiss office building stock using distributions of empirical building characteristics was coupled with a statistical model of energy savings of electrochromic glazing.The building stock model for Swiss office buildings was shown to produce cooling and lighting electricity demand estimates in agreement with the existing case study literature. Total yearly electricity demand for lighting and cooling was calculated to be 1152 ± 32 GWh. Electrochromic glazed saved 125 ± 6 GWh or on average 11% of lighting and cooling electricity demand. Electrochromic glazing was found to be particularly effective in highly cooled office buildings, where cooling accounted for 20 kWh/m2 and total electricity saving potential was estimated at 5.5 kWh/m2 or 5.2% of today’s typical total electricity demand of an office building across all uses. Areas where electrochromic glazing would have particularly high potential are highlighted.