Search Results (15)

An algorithm named ASR-BL-SA is proposed to solve the impact of a rectangular-part nesting sequence on final material utilization. Based on the Bottom Left principle, a coefficient, k, is defined as the ratio of the shape factor to 0.785 plus the square root of the min–max-normalized area. Parts are sorted in descending order of k. To tackle the flexible adaptation of part width and height via 90° rotation for sheet size and irregular leftover space, the Bottom Left algorithm initially compares utilization of original and rotated placements, selecting the option with higher utilization at each step. Finally, simulated annealing is applied for optimization. Experiments show that in the small-batch test, the proposed algorithm improves utilization by 5.51%, 3.75%, 8.84%, 5.51%, and 3.75% compared to the three baselines; in the mass production test, the improvements are 1.74%, 7.98%, 2.6%, 1.74%, and 7.89% within an acceptable time; in general applicability Test 3, its utilization is basically higher than the five comparative algorithms, achieving certain improvements in utilization. Full article

Addressing the issue of shallow-buried, closely spaced multiple coal seam repeat mining, where the development of overlying rock fractures causes interlayer airflow disturbances, leading to spontaneous combustion hazards in leftover coal and affecting the safe and efficient mining of the working face. Taking Zhangjiamao Coal Mine as the research object, a discrete element numerical model of shallow-buried, closely spaced overlying rock structure particle flow is established to study the development patterns of overlying rock fractures and the evolution of porosity in the working faces during the repeated mining processes of the 2⁻² and 4⁻² coal seams. Based on simulated data, we establish a fitting formula for the relationship between mining height, advance distance, and fracture development height. The research results indicate the following: as the working face continues to advance, the number of fractures in the overlying roof rock increases, and the fracture zones exhibit a horizontal and vertical intersecting distribution pattern, with the range continuously expanding until it extends to the surface, forming a moderately flat subsidence basin in the middle. The porosity range of the roof rock increases progressively with the mining of the working face, and the porosity of the roof rock when mining the lower coal seam is greater than that when mining the upper coal seam. The comparison between the research results and the on-site measured results verified the reliability of the simulation results. Full article

Sustainable informal learning environments are increasingly recognized as critical components of educational architecture, yet their environmental and behavioral dynamics remain underexplored. Informal learning spaces (ILS) support flexible, student-driven learning beyond formal classrooms. While prior research often isolates individual environmental factors, integrated multi-domain interactions and reciprocal occupant–space dynamics receive less attention. This study adopts a dual-perspective analytical framework, combining spatial analysis and student surveys (n = 1048) across 130 ILS in five academic buildings in China. The findings highlight several environmental dimensions influencing student experience. One extracted factor combines acoustic and thermal comfort with learning atmosphere—domains seldom grouped together—indicating their collective relevance to student experience. Additionally, spatial openness and natural connectivity further enhance student experience. Importantly, the results show that frequently used spaces receive lower physical quality ratings, group collaboration areas outperform individual study zones, and spontaneously formed spaces—informally appropriated, unplanned areas such as corridors or leftover corners—score lowest. These patterns may reflect mismatches between spatial supply and use intensity, institutional investment priorities, and differing levels of student autonomy and environmental control. This research extends conventional post-occupancy evaluations by introducing a comprehensive dual-perspective framework that links spatial characteristics with user-driven dynamics, and by identifying the combined effects of multi-domain physical environmental and supportive elements on student experience. The insights offer empirical grounding and actionable strategies for campus planners and architects, including prioritizing sensory comfort, enhancing spatial diversity, and supporting student-led adaptations to promote sustainable learning environments. Full article

As urban density increases and cities expand, there is a decrease in urban livability, which is closely linked to social, economic, and environmental crises. To address these negative impacts, biophilic urbanism (BU) promotes human–nature interactions and their associated benefits. However, knowledge gaps remain regarding its effectiveness across different scales. This study explores how BU contributes to improving livability in the built environment and to renewing urban landscapes. Using Amsterdam as a case study, we first identified biophilic experiences by analyzing them through quantitative, qualitative, and spatial distribution metrics. We then investigated designs that foster biophilia by applying BU tools aimed at enhancing interspecies connections and leveraging ecosystem services. Our findings, in the form of maps, provide evidence-based insights to benefit everyday life using nature in settings at different scales, along with design solutions to renew urban planning, focus on human and environmental well-being, and involve citizens in spatial transformations and maintenance processes. Finally, we advocate for BU as a holistic model that uses natural capital as a key strategy for making cities more equitable, sustainable, and resilient. Full article

Biomass from various types of organic waste was tested for possible use in hydrogen production. The composition consisted of lignified samples, green waste, and kitchen scraps such as fruit and vegetable peels and leftover food. For this purpose, the enzymatic pretreatment of organic waste with a combination of five different hydrolytic enzymes (cellulase, amylase, glucoamylase, pectinase and xylase) was investigated to determine its ability to produce hydrogen (H₂) with the hydrolyzate produced here. In course, the anaerobic rod-shaped bacterium T. neapolitana was used for H₂ production. First, the enzymes were investigated using different substrates in preliminary experiments. Subsequently, hydrolyses were carried out using different types of organic waste. In the hydrolysis carried out here for 48 h, an increase in glucose concentration of 481% was measured for waste loads containing starch, corresponding to a glucose concentration at the end of hydrolysis of 7.5 g·L⁻¹. In the subsequent set fermentation in serum bottles, a H₂ yield of 1.26 mmol H₂ was obtained in the overhead space when Terrific Broth Medium with glucose and yeast extract (TBGY medium) was used. When hydrolyzed organic waste was used, even a H₂ yield of 1.37 mmol could be achieved in the overhead space. In addition, a dedicated reactor system for the anaerobic fermentation of T. neapolitana to produce H₂ was developed. The bioreactor developed here can ferment anaerobically with a very low loss of produced gas. Here, after 24 h, a hydrogen concentration of 83% could be measured in the overhead space. Full article

Our study explores the question: what kind of landscape situations emerge between the urban fabric and a school building as a result of 21st-century suburbanisation? To answer this question, we will compare a traditional school town and a suburban settlement. Located less than thirty kilometres from Budapest, the traditional town is Vác, one of the most important historical school towns in Hungary. Dunakeszi, on the other hand, directly borders the capital and was a rural settlement at the beginning of the 20th century. This settlement is a typical example of urban sprawl. Its schools have occupied a place in the urban fabric since the second half of the 20th century. During our research, we used thick description and thoroughly analysed where the buildings are situated within the given urban structure, how their appearance can be described, and what their architecture communicates. Our basic argument is that while traditional settlement schools are a central element of the urban fabric, in the suburbs, schools occupy empty spaces of ‘leftover plots’ or develop new campuses in the interurban landscape. The results showed that regardless of the historical past of a given settlement, 21st-century educational institutions create separated, closed campuses in areas affected by suburbanisation processes. The primary reason for moving out is simply a lack of space in downtown areas, which is universally apparent in larger cities. The various roles and tasks schools fulfil also contribute to the process, for example the integration of sports fields or the increasing expectation to be accessible by car. Full article

This paper presents a 2-link, 2-DOF flexible manipulator control using an inverse feedforward controller and an adaptive notch filter with a direct strain feedback controller. In the flexible manipulator, transient and residue vibrations inhibit the full potential of the manipulator. Vibrations caused by abrupt changes in the direction of the links are referred to as transient vibrations, whereas residual vibrations occur when the arm takes too long to settle after engaging in the intended task. The feedforward adaptive notch filter will reduce transient vibration caused by the manipulator arm beginning and halting suddenly, while the strain feedback will assure the quick decay of leftover vibrations. Maple, Maplesim, and MATLAB tools were used to model the manipulator and create the inverse controller and adaptive notch filter. The experiments took place in the dSPACE control desk environment. The experimental results of the spectral power of strain resulting from the two strategies are compared. From the results, the adaptive notch filter control had over an 80% improvement in the reduction in resonant frequencies that contribute to vibration. The results confirmed the feasibility of the approach, characterized by very minimal transient vibrations and a quick settling of the end effector. Full article

Cities worldwide are urgently moving towards a more resilient and sustainable future. On this quest, national, regional, and local governments apply a combination of socio-spatial tools that regenerate and transform the city’s leftover spaces. There is an abundance of community gardens, cultural centers, and large-scale urban developments that, through programmed activities, reactivate underused spaces. The bearers of this process are professionals and individuals who have become aware of their actions in the contemporary urban landscape. This paper highlights possible design strategies that domesticate leftover spaces of diverse scales by injecting creative and playful programs, using Tokyo as a paradigmatic case study. More so than other global metropolises, the city represents a living laboratory for experimentation due to its compactness and the variety of urban patterns. Its leftover spaces demonstrate how play positively affects everyday life in public spaces, and how it enables extraordinary uses. A combination of ethnographic observations and spatial analysis is applied as a trans-disciplinary method. This approach allows an understanding of how people use playfulness to transform, appropriate, and utilize leftover spaces, which serves as guidance for urban planners and designers. Full article

The built environment, urban processes, and experience all work together to create the spatial environment of a city. Many urban spaces, especially those that appear to be ‘leftover’, do not reflect a set concept but are constantly questioned and recreated. Recognizing leftover spaces in an urban environment is an important aspect of the urban redevelopment process. Researchers have highlighted the difficulties, circumstances, and relevance of making good use of leftover space. To accomplish environmental and social benefits, these places can be created, changed, and incorporated into the main urban fabric; however, there is a scarcity of knowledge on how to go about constructing such environments. This study explores the visual perception of two groups of people, those with knowledge of the built environment and those with other educational backgrounds regarding leftover spaces in Wellington City. The research, which employs a mixed approach, consists of three studies, beginning with a visual preference study to better understand human perceptions, which might lead to better design solutions. The second study looked at differences in design preferences across the built environment and non-built environment participants. Finally, individuals from the built and non-built environments participants were invited to a focus group discussion for study three. To summarize, the findings demonstrated that adding vegetation is a crucial design feature. The findings refute the hypotheses of non-built environment specialists have different design perceptions for a built environment. Full article

A considerable amount of food is discarded in canteens every day. This waste has created a countermovement, where groups of mainly students purposefully choose to eat other consumers’ plate leftovers instead of buying fresh meals. This phenomenon highlights two opposing narratives: leftovers as food waste versus leftovers as edible food resources. Using a thematic analysis, we investigated 1579 comments from German news sites and their corresponding Facebook sites related to this countermovement. Thereby, we aim to better understand what consumers associate with the consumption of other consumers’ plate leftovers. Our study demonstrates that the consumption of plate leftovers is shaped by the regulatory, normative, and cultural-cognitive system. Furthermore, associations with the consumption of plate leftovers depend on whether this food decision is perceived as a collective or individual consumer decision. From a consumer movement perspective, food leftover consumption is associated with a sense of community and food waste reduction for idealistic or environmental and social reasons. From an individual consumer behavior perspective, food leftover consumption is associated with satisfying hunger but considered a threat to health and social order. Our findings can inspire food service organizations to develop targeted interventions for plate leftover reduction. Full article

Pedestrian facilities have been regarded in urban street design as “leftover spaces” for years, but, currently, there is a growing interest in walking and improving the quality of street environments. Designing pedestrian facilities presents the challenge of simultaneously accommodating (1) pedestrians who want to move safely and comfortably from point A to B (movement function); as well as (2) users who wish to rest, communicate, shop, eat, and enjoy life in a pleasant environment (place function). The aims of this study are to provide an overview of how the task of designing pedestrian facilities is addressed in international guidance material for urban street design, to compare this with scientific evidence on determinants of pedestrian activities, and to finally develop recommendations for advancing provisions for pedestrians. The results show that urban street design guidance is well advanced in measuring space requirements for known volumes of moving pedestrians, but less in planning pleasant street environments that encourage pedestrian movement and place activities. A stronger linkage to scientific evidence could improve guidance materials and better support urban street designers in their ambition to provide safe, comfortable and attractive street spaces that invite people to walk and to stay. Full article

The success of university campuses depends on the interrelations between creative encounters and the built environment, conceptualised here as spatial affordances for creativity. Such an interface plays a fundamental role in interactions for knowledge sharing and the exchange of ideas on campus. Due to campus public spaces generally being considered as the leftovers between buildings and classrooms, undermanaged, and overlooked, little is known about the extent to which this built environment enables or inhibits creative encounters in such spaces. The inner-city campuses and science parks (SPs) of Amsterdam and Utrecht, the case-studies of this research, differ in terms of their location relative to the city, their masterplan typologies and the arrangement of buildings. However, they are similar in terms of the aforementioned issues of public spaces. The novelty of this research is the attempt to overcome such issues using an innovative mixed-methods approach that tests the ‘spatial affordances for creativity’ with empirical data collection and analysis. This raises the importance of mapping, quantifying and analysing the spatial distribution of momentary perceptions, experiences, and feelings of people with methods such as volunteered geographic information (VGI). The results show that proximity between multiple urban functions and physical features, such as parks, cafés and urban seating are important when it comes to explaining the high frequency of creative encounters between people. Urban designers of campuses can use the applied method as a tool to plan and design attractive public spaces that provide creativity through the transfer of tacit knowledge, social well-being, positive momentary perceptions, sense of community, and a sense of place. Full article

Previous studies have proposed various frameworks and algorithms to optimize routes to reduce total transportation cost, which accounts for over 29.4% of overall logistics costs. However, it is very hard to find cases in which mathematical models or algorithms are applied to practical business environment cases which require reusable packaging, especially daily operating logistics services like convenience store support systems. Most previous studies have considered developing an optimal algorithm which can solve the mathematical problem within a practical amount of time while satisfying all constraints, such as the capacity of delivery and pick-up, and hard or soft time windows. For daily delivery and pick-up services, like those supporting several convenience stores, it is required to consider the unit transporting the container, as well as the demand, capacity of trucks, travel distance, and traffic congestion. In particular, reusable transport containers and trays should be regarded as important assets of logistics centers. However, if the mathematical model focuses on only satisfying constraints related to delivery and not considering the cost of trays, it is often to leave the empty trays on the pick-up points when there is not enough space in the track. In this study, we propose a mathematical model for optimizing delivery and pick-up plans by extending the general vehicle routing problem of simultaneous delivery and pick-up with time windows, while considering left-over cost. With numerical experiments it has been proved that the proposed model may reduce the total delivery cost. Also, it seems possible to apply the proposed approach to the various logistics businesses which require reusable transport containers like shipping containers, refrigerating containers, trays, and pallets. Full article

The Urban Heat Island phenomenon and urban overheating are serious consequences of urbanization resulting in impacts on thermal comfort levels, heat stress and even mortality. This paper builds on previous findings on the topic of non-constructible parcels, small vacant or built spaces in Municipal Beirut, some of which belong to the municipality while others are privately owned and which might be used for different functional purposes. This paper further examines the possibility of implementing cool surface or paving materials and urban vegetation to reduce air urban temperature, especially during the summer period and with the view to project the positive findings of this case study to the entire Municipal Beirut area. A numerical analysis using ENVI-met 4.0 investigates the thermal performance of these non-constructibles further to implementation of high reflective surfaces and urban vegetation on a broad neighborhood scale, taking the Bachoura District as a reference case for a typical summer day. The best air temperature reductions correspond to the use of cool material in areas that are far from buildings where there are no shadow effects. In some cases, the introduction of trees leads to an increase of the air temperature near the ground because they became an obstacle of the natural ventilation. Results show a maximum mitigation effect with the use of cool materials that lead to reductions in air temperatures up to 0.42 °C if used alone and up to 0.77 °C if used in combination with trees. Within the framework of an integrated approach to planning, this form of urban intervention aims for substantial overheating reduction. Full article