Small Space Research Articles

Effects of single- or pair-housing on the welfare of shelter dogs: Behavioral and physiological indicators.

Dogs are often housed alone in shelter settings to reduce injury and disease spread. However, social isolation can be a stressor for dogs. Prior studies have suggested that cohousing can produce behavioral and physiological benefits. These studies have typically focused on laboratory dogs or shelter dogs that have been kenneled for several months. Thus, those results might not necessarily generalize to shelter dogs, many of which have shorter lengths of stay than those dogs studied to date, and might be cohoused soon after intake. In fact, being pair-housed could, in the short term, be more stressful as dogs have to navigate novel social situations in small spaces. We investigated the behavioral and physiological effects of single- or pair-housing shelter dogs, most of which had recently entered the shelter. We collected behavioral data on 61 dogs (30 single-housed; 31 pair-housed) daily across seven days; we also collected urine for cortisol:creatinine analysis on a subset (22 single-housed; 18 pair-housed) for eight days (each day of the seven-day study plus a baseline sample on Day 0, prior to dogs' enrollment). We found pair-housed dogs engaged in three stress-related behaviors (lip licking, whining, and ears back) significantly less frequently than single-housed dogs. When we analyzed the change in urinary cortisol:creatinine (Days 1-7 values minus Day 0 value), we found that pair-housed dogs generally showed a greater decrease in cortisol:creatinine levels than single-housed dogs. Pair-housed dogs also had significantly shorter lengths of stay, but we did not detect any effect on dog-dog skills. Overall, we found well-matched pair-housing can have both proximate and ultimate welfare benefits for shelter dogs.

An Integral-like Numerical Approach for Solving Burgers’ Equation

The Burgers’ equation, commonly appeared in the study of turbulence, fluid dynamics, shock waves, and continuum mechanics, is a crucial part of the dynamical core of any numerical weather model, influencing simulated meteorological phenomena. While past studies have suggested several robust numerical approaches for solving the equation, many are too complicated for practical adaptation and too computationally expensive for operational deployment. This paper introduces an unconventional approach based on spline polynomial interpolations and the Hopf-Cole transformation. Using Taylor expansion to approximate the exponential term in the Hopf-Cole transformation, the analytical solution of the simplified equation is discretized to form our proposed scheme. The scheme is explicit and adaptable for parallel computing, although certain types of boundary conditions need to be employed implicitly. Three distinct test cases were utilized to evaluate its accuracy, parallel scalability, and numerical stability. In the aspect of accuracy, the schemes employed cubic and quintic spline interpolation perform equally well, managing to reduce the <i>ӏ</i><sub>1</sub>, <i>ӏ</i><sub>2</sub>, and <i>ӏ</i><sub>∞</sub> error norms down to the order of 10<sup>−4</sup>. Parallel scalability observed in the weak-scaling experiment depends on time step size but is generally as good as any explicit scheme. The stability condition is <i>ν</i>∆<i>t</i>/∆<i>x</i><sup>2</sup> > 0.02, including the viscosity coefficient <i>ν</i> due to the Hopf-Cole transformation step. From the stability condition, the schemes can run at a large time step size ∆<i>t</i> even when using a small grid spacing ∆<i>x</i>, emphasizing its suitability for practical applications such as numerical weather prediction.

Mobile Phone Based Indoor Mapping

Abstract. We presented a mobile phone scanning solution that offers a workflow for scanning not only small spaces, where drift can be neglected, but also larger spaces where it becomes a major accuracy issue. The LiDAR and image data is combined to build 3D representations of indoor spaces. The paper does focus on the drift compensation for larger scans on the mobile phone by using AutoTags detections. We show that those can also be used to combine scans from multiple independent scans.

Analysis and Real-Time Monitoring of the Influence of Wind Load on a High-Altitude Steel Connecting Bridge with Small Spacing

With the development of steel-structure construction technology in high-rise buildings, the design and construction of high-rise steel structures tend to be complicated. Based on the Zhuhai Tiejian Square project, the fluid-structure coupling calculation analysis and on-site monitoring are carried out in view of the wind load of the high-altitude steel-structure connecting bridge in the hoisting stage of the Zhuhai Tiejian Square project. The main structure of the project is four towers and five high-altitude, small-spacing steel structures connecting the four towers. The lifting process of the third zone is taken as the analysis object, and the hoisting idea of “low-altitude hoisting, overall lifting” is adopted. Because the span of the high-altitude steel-structure connecting bridge is small and the installation height is high, the influence of wind load on the hoisting process cannot be ignored. Therefore, the unidirectional fluid-structure coupling model of the high-altitude small-space steel-structure connecting bridge in the third zone was established by using CFD calculation software ANSYS Fluent 2022 R1, and the corresponding flow field and solid calculation results were obtained and analyzed. The analysis results show that the lifting structure still produces a certain deformation when the wind speed is 5 m/s or 10 m/s, and the calculation results show that the stress calculation results are still within the safe range of steel strength for the sensitivity of the lifting structure under wind load. With the increase of wind speed, the local maximum stress of the structure increases greatly, but the overall deformation remains stable, which indicates that the greatest challenge of hoisting steel structures under wind load may be the stability direction rather than the strength, so it is necessary to strictly monitor the displacement deformation of the structure during construction. Then, through the monitoring of the overall lifting process of the high-altitude, large-span, steel-connected structure of Zhuhai Tiejian Square from pre-lifting to formal lifting, real-time monitoring and data analysis show that the lifting process of the high-altitude steel bridge of Zhuhai Tiejian Square is safe and reliable, the force transformation of each component is reasonable, the lifting process is relatively stable, the external environment has little impact, and the expected monitoring effect has been achieved. The calculation simulation and on-site monitoring in this paper can provide theoretical and practical guidance for the construction safety under the influence of wind load in the construction process of high-altitude steel-structure hoisting, and provide an important reference value for similar projects.

New perspectives and moving targets to improve biodiversity and urban resilience

This paper shows some results of the research activities carried out in the spoke five of the National Biodiversity Future Center aimed at testing the effectiveness of urban regeneration projects, including the creation of Pocket Parks as adaptation strategies to climate change. The methodological approach adopted to validate the design of small scale resilient urban spaces implemented by the Municipality of Florence will be presented starting from the definition of state-of-the-art. Furthermore, it will analyse how the meta-planning model (based on the integration of NbS) and the predictive tools used in the experimentation can be used to develop future regulatory tools for planning and controlling the transformation of the built environment.

Should I make it round? Suitability of circular and linear layouts for comparative tasks with matrix and connective data

AbstractVisual representations based on circular shapes are frequently used in visualization applications. One example are circos plots within bioinformatics, which bend graphs into a wheel of information with connective lines running through the center like spokes. The results are aesthetically appealing and impressive visualizations that fit long data sequences into a small quadratic space. However, the authors' experiences are that when asked, a visualization researcher would generally advise against making visualizations with radial layouts. Upon reviewing the literature we found that there is evidence that circular layouts are preferable in some cases, but we found no clear evidence for what layout is preferable for matrices and connective data in particular, which both are common data types in circos plots. In this work, we thus performed a user study to compare circular and linear layouts. The tasks are inspired by genomics data, but our results generalize to many other application areas, involving comparison and connective data. To build the prototype we utilized Gosling, a grammar for visualizing genomics data. We contribute empirical evidence on the suitedness of linear versus circular layouts, adding to the specific and general knowledge concerning perception of circular graphs. In addition, we contribute a case study evaluation of the grammar Gosling as a rapid prototyping language, confirming its utility and providing guidance on suitable areas for future development.

Optimization of Uplift Piles for a Base Plate Considering Local Anti-Floating Stability

This paper focuses on the optimization of uplift piles for a base plate considering local anti-floating stability. According to the force characteristics of the base plate subjected to buoyancy, a bi-directional evolutionary structural optimization (BESO) process is proposed. The optimization process takes the pile length as the design variable and the pile end displacement as the sensitive coefficient. The proposed process is conducted with FLAC3D to optimize the length of each uplift pile, including two cases with different pile diameters and spacing. The optimization process shows that the deformation degree of the base plate is significantly reduced when the piles are adopted with large diameters and sparse spacing, and oscillates at a low level when the piles are adopted with small diameters and dense spacing. Consequently, the design method of uplift piles considering the local anti-floating stability is proposed by referring to the optimization results of two cases. Finally, the proposed design method is applied to a practical project, and the original design of the uplift piles is optimized. The comparison results show that the deformation degree of the base plate of optimization designs is significantly lower than the original design.

Indoor concentrations of radioactive aerosols from nuclear accidents.

In previous studies, some of the important factors that affect the spread of radioactive aerosols into indoors were considered. The studies were based on a new CFD approach and provided good descriptions for the deposition of aerosol particles inside small spaces and the penetration of aerosols into buildings through wall cracks. In this article, an application of those studies is implemented, where all the graphical relations that are required to estimate the indoor concentrations of radioactive aerosols from nuclear accidents are provided. This includes the deposition velocities, deposition rate, and the penetration factor. Particular interest is in the Fukushima-Daiichi nuclear power plant accident that took place in Japan in 2011. The aerosols carrying the radioiodine iodine-131 and the radiocesium cesium-134 and cesium-137 are studied. Based on the model's assumptions, and assuming steady-state air concentrations, the radioactive aerosols' concentrations in indoor air are about 97% of the concentrations in outdoor air. The applications demonstrate the model to be convenient and practical.

Risk ambassadors and saviours: Children and futuring public health interventions.

Schools are increasingly positioned as sites for intervening on the bodies and minds of children in the here and now in order to bring about health gain for the future. Public health interventions for schools bring together coalitions of commercial, statutory and philanthropic actors with children and their teachers and carers. Drawing on ethnographic case studies in London, UK, this paper explores two such interventions: one aiming to increase levels of physical activity and one to reduce exposure to air pollution. Both interventions not only evoke care for children's own current and future wellbeing but also fold in imaginaries of collective health futures, which orient and legitimise particular intervention logics and actions. As interventions unfold, children are recruited as monitors of health risks in the present. They are also positioned as risk ambassadors, who will leverage care about unhealthy environments and lifestyles across space, to risky domestic environments, and into imagined health futures. These 'futuring' school-based interventions open up small alternative spaces in which imaginaries of collective and resistant public health practices emerge. However, in the here and now, children appear to be bearing a disproportionate burden of responsibility, as ambassadors for, and imagined saviours of, public and environmental health.

Valorization of wastewater from industrial hydroponic cultivations using the microalgal species Chlorella vulgaris

The continuous increase in the world population is associated with a greater demand for food. This need has driven the development of new cultivation systems capable of producing large quantities of vegetable biomass in a small space, with precise and regulated control of the use of resources. Among these, vertical farms are systems developed in height, and they produce continuously throughout the year.The hydroponic system is commonly used in vertical farming and entails the growth of plants in a solution rich in nutrients, easily assimilated by plants. However, hydroponic solutions still contain nutrient salts at the end of the productive cycle. Consequently, spent hydroponic solutions cannot be directly released into the environment because they would cause water pollution. Thus, they need to be appropriately treated, increasing production costs.Microalgae represent a cost-effective solution for treating and valorizing hydroponic wastewater. They can easily consume the residual nutrients, generating valuable biomass that can be exploited as a biofertilizer, a biostimulant, or even as a valuable food supplement.The present work showed the ability of the model eukaryotic microalga Chlorella vulgaris to use valuable resources derived from industrial cultivations of basil and tobacco in a hydroponic deep-water culture system. Although the use of spent hydroponic solutions slightly affected the microalgal biomass accumulation of more than ~40 % compared to the fresh solution, possibly due to the presence of root exudates that have an antagonistic effect toward microalgae, the phytoremediation activity of microalgae was achieved. The reported results described the consumption of more than 80 % and 70 % of P and N residual nutrients in hydroponic formulations, respectively. Moreover, more than 2 g/L of microalgal biomass was generated after 7 days of growth in air-lifted photobioreactors. The outcomes of this research provide new insights toward greater sustainability of vertical farming, following circular economy principles.

An enhanced NSGA-II and a fast constraint repairing method for combined heat and power dynamic economic emission dispatch

In this paper, an enhanced NSGA-II (ENSGA-II) is presented for the combined heat and power dynamic economic emission dispatch (CHPDEED). ENSGA-II produces offspring individuals by a novel crossover of the Cauchy distribution with adaptive location and scale parameters. It can not only sufficiently explore and exploit the decision space but also remain a relatively high population diversity. Also, ENSGA-II adopts a modified crowding distance to penalize crowded individuals, seeking to evenly distribute the individuals in the objective space. In addition, a fast constraint repairing method (FCRM) is proposed to significantly reduce the constraint violations and guide infeasible individuals to move towards feasible zones rapidly. The proposed ENSGA-II is applied to a number of multi-objective optimization problems and compared with the other eight multi-objective evolutionary algorithms (MOEAs). ENSGA-II is found to produce better results on most problems, such as smaller inverse generational distances, larger hypervolumes, larger coverage rates and smaller spacings. Therefore, ENSGA-II can obtain a satisfactory Pareto set with broad spread, high diversity, strong convergence and good evenness, and it is an efficient alternative for CHPDEED.

On the impact of different static induction control strategies on a wind turbine wake

This study provides a wind tunnel investigation to identify effective ways of derating an upstream turbine for mitigating wake-induced power losses. Short-range continuous-wave lidar measurements are used to remotely map the time-averaged wake characteristics of a controllable model wind turbine under uniform inflow with negligible turbulence. The analysis focuses on comparing four distinct static induction control (SIC) strategies, each at targeted derating levels of 5 % and 10 %, against a conventional greedy strategy. The results indicate that pitch-to-feather combined with an increased tip-speed ratio is the most favourable approach for minimising wake losses in a two-turbine setup. Notably, power gains of up to 3.8 % are achieved for partial and full wake overlap conditions at 5 % derating and small turbine spacing. These observations are consistent with previous field experiments, suggesting that SIC may be advantageous in wind farms with closely spaced turbines. Overall, these findings underscore the importance of carefully selecting and understanding the implemented derating strategy for supporting wind farm flow control applications.

Tight contact structures on some families of small Seifert fiber spaces

Suppose K is a knot in a 3-manifold Y, and that Y admits a pair of distinct contact structures. Assume that K has Legendrian representatives in each of these contact structures, such that the corresponding Thurston-Bennequin framings are equivalent. This paper provides a method to prove that the contact structures resulting from Legendrian surgery along these two representatives remain distinct. Applying this method to the situation where the starting manifold is -Σ(2,3,6m+1)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$-\\Sigma(2,3,6m+1)$$\\end{document} and the knot is a singular fiber, together with convex surface theory we can classify the tight contact structures on certain families of Seifert fiber spaces.

Tolerance analysis of slat gear rotary actuator in civil aircraft

Abstract The slat gear rotary actuator of civil aircraft needs to meet the requirements of small space and large transmission ratio. The planetary gear system based on triple teeth is a common actuator design, and the design structure is complex, so its tolerance control is also strict. In order to meet the design requirements of its internal structure, this paper presents a deviation analysis method for the internal structure design of a typical civil aircraft slat gear rotary actuator. The results of preliminary tolerance distribution and improved tolerance distribution are analyzed using the Jacobi-based assembly deviation model. By comparing the standard deviation of the analysis results, the validity of this deviation analysis method is verified, which proves that this method can be used to analyze the internal structure deviation of the rotary actuator of slat gear in civil aircraft.

A triangle decomposition method for the mobility control of mecanum wheel-based robots

Mobile robots are used in a variety of applications including research, education, healthcare, customer service, security and so on. Based upon the application, the robots employ different locomotion systems for their mobility. When it comes to rolling locomotion, the wheels used to provide mobility to robots can be categorized as: tracks, omnidirectional wheels, and unidirectional wheels with a steering system. The ability of omnidirectional wheels to drive machines in small spaces makes them interesting to use. Among the types of omnidirectional wheels, mecanum wheels are widely used due to their inherent benefits. With the right control strategy, robots equipped with mecanum wheels can move freely, in all possible directions. In this study, a triangle decomposition approach is employed for controlling omnidirectional mecanum wheel-based robots. The method consists of breaking down any path into a set of linear motions that can be horizontal, vertical, or oblique. Furthermore, the oblique paths are divided into smaller segments that can be resolved into a horizontal and vertical component in a right-angle triangle. The suggested control method is tested and proved on a simple scenario using Webots simulation software.

Feasibility of using CubeSats and small detectors for in-situ space debris and cosmic dust flux measurement

Impacts on spacecraft by mm-sized debris in Earth orbit can have severe consequences including loss of a spacecraft and generation of more debris. This hazard and potential mitigation are discussed herein, and the risk of an impact (the product of flux and damage) is found vs. size. Reduction of the future flux of mm-sized debris by de-orbiting life-expired space vehicles, only reduces, not eliminates, this hazard. It is thus vital that the flux of mm-sized objects in orbit is well defined, but this requires on-orbit determination. To provide statistically meaningful debris flux data, large detection areas are traditionally required. CubeSats could host debris detectors, but only have small surface areas, and the data from many would be required. Accordingly, flux data from historic small space exposed surfaces are compared herein to MASTER flux model predictions, with good agreement for exposure times of just a few years, demonstrating a viable method to determine the debris flux. The cost of a network of CubeSat mounted impact detectors is also estimated found, and, for fleets of order 100 CubeSats, is comparable to the traditional single large satellite mounted instrument.

A study on factors influencing the spatial oppressiveness in small courtyard spaces within university residential areas

ABSTRACT A number of obstacles in terms of the growing demand for residential spaces for students in China's education industry. Changing urban development patterns often lead to densely populated, unpleasant university residential neighborhood, posing threats to the well-being of university personnel. This study addresses the limitations of past research, focusing on a real campus's enclosed high-rise student apartment courtyard. Using three key design variables (courtyard area, building height and ground-level interface transparency), 27 sample scenarios were developed for psychological experiments. The findings indicate that while visual scene complexity has minimal impact on oppression to confined environments, building exposure and sky visibility do. People's perception of openness is determined by building exposure, sky visibility, and visual complexity. Higher visual complexity and greater sky visibility enhance the sense of openness. Satisfaction is primarily influenced by sky visibility. The study also conducts a multiple linear regression of spatial and psychological indicators and discusses the tolerance threshold for spatial oppressiveness and the spatial oppressiveness under various spatial types of samples.

SIMPLE: Efficient Temporal Graph Neural Network Training at Scale with Dynamic Data Placement

Dynamic graphs are essential in real-world scenarios like social media and e-commerce for tasks such as predicting links and classifying nodes. Temporal Graph Neural Networks (T-GNNs) stand out as a prime solution for managing dynamic graphs, employing temporal message passing to compute node embeddings at specific timestamps. Nonetheless, the high CPU-GPU data loading overhead has become the bottleneck for efficient training of T-GNNs over large-scale dynamic graphs. In this work, we present SIMPLE, a versatile system designed to address the major efficiency bottleneck in training existing T-GNNs on a large scale. It incorporates a dynamic data placement mechanism, which maintains a small buffer space in available GPU memory and dynamically manages its content during T-GNN training. SIMPLE is also empowered by systematic optimizations towards data processing flow. We compare SIMPLE to the state-of-the-art generic T-GNN training system TGL on four large-scale dynamic graphs with different underlying T-GNN models. Extensive experimental results show that SIMPLE effectively cuts down 80.5% ~ 96.8% data loading cost, and accelerates T-GNN training by 1.8× ~ 3.8× (2.6× on average) compared to TGL.

A Reliability Assessment Method for Complex Systems Based on Non-Homogeneous Markov Processes.

The Markov method is a common reliability assessment method. It is often used to describe the dynamic characteristics of a system, such as its repairability, fault sequence and multiple degradation states. However, the "curse of dimensionality", which refers to the exponential growth of the system state space with the increase in system complexity, presents a challenge to reliability assessments for complex systems based on the Markov method. In response to this challenge, a novel reliability assessment method for complex systems based on non-homogeneous Markov processes is proposed. This method entails the decomposition of a complex system into multilevel subsystems, each with a relatively small state space, in accordance with the system function. The homogeneous Markov model or the non-homogeneous Markov model is established for each subsystem/system from bottom to top. In order to utilize the outcomes of the lower-level subsystem models as inputs to the upper-level subsystem model, an algorithm is proposed for converting the unavailability curve of a subsystem into its corresponding 2×2 dynamic state transition probability matrix (STPM). The STPM is then employed as an input to the upper-level system's non-homogeneous Markov model. A case study is presented using the reliability assessment of the Reactor Protection System (RPS) based on the proposed method, which is then compared with the models based on the other two contrast methods. This comparison verifies the effectiveness and accuracy of the proposed method.

Colour Perception in Camper Van Interior Design Using Virtual Reality Technology

Virtual reality (VR) technology has been developing progressively and rapidly in the past decades. VR technology is used to create 3D models of rooms and spaces, which can be used to create more accurate and detailed designs. Colours used in interior design have the ability to create specific moods, create harmony, and change the perception of how large or small a space may look or feel. The purpose of this study is to explore the application of virtual reality technology in the interior design of a camper van considering the role of colour perception. We aim to determine the effect of colour on the interior design creating professional-looking 3D camper van layout. The results show that any non-professional in 3D design can design a functional and comfortable living space in the camper van using Vanspace 3D software. It was found that light colours and shades create the feeling of space, light, comfort and cosiness. When choosing colours for the interior design of a small limited space, as is the case with a camper van, it is advisable to combine warm earth colours, white and beige colours.