Evaluating 3D Reconstruction: A Side-by-Side Comparison of NeRF and Gaussian Splatting in Indoor and Outdoor Environments

This study presents a comparative evaluation of Neural Radiance Fields (NeRF) and 3D Gaussian Splatting (3DGS) for 3D reconstruction under various filming techniques. High-quality 3D models are essential in a range of applications, from forensic investigations to cultural heritage preservation, architecture, and robotics, where detail accuracy and minimal noise are critical. Leveraging continuous video footage captured with a stabilized full-frame camera setup, this research examines both algorithms across indoor and outdoor environments using consistent datasets. Key assessment criteria include reconstruction noise, detail preservation, and processing time. The results reveal that while both approaches generate high-fidelity reconstructions, 3DGS consistently outperforms NeRF in computational efficiency and noise reduction. These insights provide valuable guidance for selecting suitable reconstruction techniques across different professional domains.

Psychological aspects of “environmental illness,” “multiple chemical sensitivity,” and building-related illness

Psychological aspects of ″environmental illness,” ″multiple chemical sensitivity,” and building-related illness

The peculiar problem of unstable power supply in developing countries was a motivating factor for this research work. The problem of power supply is being resolved by renewable energy such as tidal, solar PV-based renewable energy, geothermal and solar renewable energy. The performance of three basic solar panel types kept in an indoor environment with an artificial light source and reflector was compared with the performance under outdoor environment. These solar PV types includes monocrystalline, polycrystalline, and silicon-amorphous which selected as a sample for the thin-film type of solar panel. Laboratory experiments were set up for these tests. PWM (pulse width modulation) concept of controlling AC was employed to achieve control for the enclosed indoor experiment. This was used to vary the intensity of the light bulbs placed inside the chamber built for the enclosed indoor environment. Reflectors were placed on the walls of the chamber to achieve better illumination within the chamber: thereby leading to better output efficiency from the panels being tested. From the obtained results, monocrystalline solar panel gave 25.45V, polycrystalline produced 26.68V and Silicon-amorphous gave 25.49V for the indoor experiment when the highest obtainable PWM voltage was 250V. The results obtained for the outdoor readings fluctuate because of the factors militating against PVs. The highest readings obtained for the panels were: 25.78V, 24.56V and 24.08V for monocrystalline, polycrystalline and silicon-amorphous respectively. From these obtained results, the deduction made was that monocrystalline PV has the highest output efficiency under outdoor environment while the polycrystalline PV has the highest efficiency under indoor environment. This paper worked on the comparative analysis of the results obtained for both indoor and outdoor environments

We developed a multimedia satellite network system based on the Internet protocol (IP) and personal computers. It enables collaborative distance education between outdoor and indoor environments. Integration of IP technologies and satellite communications enhances the flexibility of the network system. The satellite communication system enables us to communicate to and from outdoor environments where terrestrial infrastructures are poor or do not exist. Personal-computer-based systems allow us to utilize already available software and to make the outdoor system portable and easy to install outdoors. We conducted an experiment for collaborative distance education between a farm and an immersive display environment by using the multimedia satellite communication system and a transportable Earth station outdoors. The experiment showed that our system could be used for collaborative distance education between outdoor and indoor environments, and could reduce the amount of equipment needed outdoors.

In this paper, user-position estimation method is proposed by using a single camera for both indoor and outdoor environments. Conventionally, the GPS of RF-based estimation methods have been widely studied in the literature for outdoor and indoor environments, respectively. Each method is useful only for indoor or outdoor environment. In this context, this study adopts a vision-based approach which can be commonly applicable to both environments. Since the distance or position cannot be extracted from a single still image, the reference images pro-stored in image database are used to identify the current position from the single still image captured by a single camera. The reference image is tagged with its captured position. To find the reference image which is the most similar to the current image, the SURF algorithm is used for feature extraction. The outliers in extracted features are discarded by using RANSAC algorithm. The performance of the proposed method is evaluated for two buildings and their outsides for both indoor and outdoor environments, respectively.

A numerical simulation tool for predicting the impact of outdoor thermal environment on building energy performance

Qualitative and quantitative analyses of airborne fungal spores and pollen grains in four working environments (market, saw mill, poultry and cow sheds) in Thiruvananthapuram, the capital city of Kerala, India, were carried out for 2 years using Burkard Personal Slide Sampler and Andersen Two-Stage Sampler. Total spore concentration in these sites was always higher in indoor environments than in outdoor environments. Difference in concentration was not statistically significant in any of these work places except in saw mill (t test, p < 0.05). The highest spore concentration was recorded here followed by market, poultry and cow sheds. A total of 32 fungal spore types from indoor environments and 33 spore types from outdoor environments were recorded. Of them, 16 spore types were common to all the sites. Ameropsores, Cladosporium, other basidiospores, Ganoderma and Nigrospora were the dominant spore types in both indoor and outdoor environments. A total of 27 species of viable fungi from indoor and 24 species from outdoor environments were identified. Penicillium citrinum, Aspergillus flavus and Aspergillus niger were the most dominant viable fungi isolated. In contrast, total pollen concentration was always higher in outdoor environments than in indoor environments. Twenty-nine pollen types from indoor and 32 pollen types from outdoor were captured during the sampling. Poaceae, Cocos, Artocarpus, Amaranthus/Chenopodium and Tridax were the common and dominant pollen types observed in all the sites. Peak spore and pollen incidence were recorded during the late rainy and dry seasons (October–February) in both indoor and outdoor environments. The study revealed high prevalence of predominantly allergenic fungal spores and pollen grains in all the four work places. Workers/visitors are at potential risk of susceptibility to respiratory/allergic disorders.

The objective of this study was to make an evaluation of Wi-Fi radiofrequency fields in campus of Ricardo Palma University in the Surco district, Lima, Perú using personal exposure meters. To carried it out a literature review was first made, then the location of the environments was defined. In total 96 outdoor and 10 indoor environments were selected. Subsequently, the exposure meter including the proprietary software for data processing was tested. The maximum contribution of Wi-Fi 2G and Wi-Fi 5G for outdoor environments by main frequency bands to average exposure were 1.83 x 10-6 and 3.39 x10-5 W/m2 respectively and the maximum contribution of Wi-Fi 2G and Wi-Fi 5G for indoor environments by main frequency bands to average exposure were 1.33 x 10-6 and 2.96 x10-6 W/m2 respectively. Based on the ICNIRP 1998 limits, the exposure quotients were also obtained the maximum contribution of Wi-Fi 2G and Wi-Fi 5G for outdoor environments by main frequency bands to average exposure were 1.83 x 10-5 and 3.39 x10-4 % respectively and the maximum contribution of Wi-Fi 2G and Wi-Fi 5G for indoor environments by main frequency bands to average exposure were 1.33 x 10-5 and 2.96 x10-5 W/m2 respectively. In conclusion, all measurements made were well below international limits, for outdoor and indoor environments the largest contributor to total exposure was broadcasting services, the second largest were mobile phone base stations, for outdoor environments the third largest was Wi-Fi 5G and mobile phone handsets exposure was well below that of mobile phone base stations and for indoor environments the third largest was mobile handsets and the last one was Wi-Fi.

Navigation systems are designed to assist people or objects in moving efficiently and accurately from one place to another by providing directions to reach a destination. There are two main types of navigation systems: Indoor Navigation, which involves navigation within indoor environments, and Outdoor Navigation, which is used in outdoor or open environments. Both have drawbacks, such as signal limitations in multi-floor buildings and hardware requirements. This study focuses on developing a Seamless Indoor-Outdoor Navigation System that integrates indoor and outdoor navigation within a single application, allowing users to seamlessly transition between environments without switching applications or requiring additional hardware. The development uses AR technology and Immersal, overlaying digital content such as 3D pinpoints and 3D paths onto the real world through smartphones to show destinations to users. Immersal SDK adds real-world location mapping, application development, and localization for indoor and outdoor environments. The system was implemented at the PENS Campus, and testing was conducted, including: 1) Navigation Testing, which demonstrated efficient route visualization in the D3, D4, and S2 buildings and PENS Road. 2) User testing with the PIECES Framework, involving 35 respondents, showed high satisfaction with a top score of 4.49 for Information. 3) Indoor-outdoor integration Testing confirmed the system’s success in navigating between environments. 4) Multilevel Floor Navigation Testing demonstrated its ability to navigate multi-floor buildings, 5) Software Testing showed the system's performance met targeted frame rates of 30 FPS for Android and 60 FPS for iOS devices.

Providing high data rates and wide bandwidth applications are the most important challenges that mobile systems and radio networks are trying to accomplish. Radio over Fiber-RoF systems is a promoting research field since it benefits of Passive Optical Network (PON) advantages and unlicensed large bands in 60 GHz millimeter band (57-64GHz). In this study, we consider a complete RoF system from the central office to the end-user passing by the base station and we study the impact of propagation environment on the whole system performance and radio coverage by considering different scenarios for multipath propagation (Line of Sight-LOS, Non Line of Sight-NLOF). In particular, we have been interested in Rayleigh and Rice propagation models for both indoor and outdoor environments. Optisystem/ADS Co-simulation has been investigated to simulate RoF network coverage for indoor and outdoor environments while considering high data rates.

Human activity recognition (HAR) based on Channel State Information (CSI) has been widely concerned in recent years due to its properties of low cost and privacy protection. Whats more, unlike vision-based and sensor-based HAR systems, it is not sensitive to illumination intensity and does not need any accessory equipment. The detection threshold in existing HAR system is set manually thus require researchers to reset the threshold when environment changes or a new activity needs to be recognized. The utilization of single classifier with poor robustness cannot achieve a high recognition accuracy. We propose a CSI-based Device-free HAR (CDHAR) system to recognize common human activities, such as ‘Walk’, ‘Run’, ‘Sit down’, ‘Squat’ and ‘Fall down’. First of all, CDHAR obtain an adaptive detection threshold to complete the extraction of activity durations. Second, it proposes a random subspace classifier ensemble method for classification. At last, we prototype CDHAR on commodity WiFi devices and evaluate its performance both in typical indoor and outdoor environments. Our results show even experimental site changes, the extraction accuracy rate can achieve 99.80% and 99.60% in outdoor and indoor environment, respectively. Based on the extracted data, the recognition accuracy rate can reach 91.2and 90.2% in outdoor and indoor environment, respectively. CDHAR solves the problem of setting the detection threshold manually and overcomes the low robustness of the single classifier at the same time. Furthermore, the results in above two scenarios demonstrate that CDHAR can also achieve slightly recognition accuracy improvement over existing recognition methods.

Many children fail to meet physical activity (PA) guidelines for health benefits. PA behaviours are complex and depend on numerous interrelated factors. The study aims to develop current understanding of how children from low Socio-economic environments within the UK use their surrounding built environments for PA by using advanced technology. The environment was assessed in 96 school children (7–9 years) using global positioning system (GPS) monitoring (Garmin Forerunner, 305). In a subsample of 46 children, the environment and PA were assessed using an integrated GPS and heart rate monitor. The percentage of time spent indoor, outdoor, in green and non-green environments along with time spent in moderate-to-vigorous PA (MVPA) in indoor and outdoor environments were assessed. A 2-by-2 repeated measures analysis of covariance, controlling for body mass index, BF%, assessed the environmental differences. The findings show that 42% of children from deprived wards of Coventry fail to meet PA guidelines, of which 43% was accumulated during school. Children engaged in more MVPA outdoor than indoor environments (P < 0.01) and a greater amount of time was spent in non-green environments (P < 0.01). Increased time outdoors was negatively associated with BF%. In conclusion, outdoor environments are important for health-enhancing PA and reducing fatness in deprived and ethnic children.

Levels of Airborne Bacteria in a School Classroom Environment in Doha Qatar

Background and aim: Occupational exposure to particles can raises important health issues for exposed workers. High concentrations of these particles can be found in a variety of occupational and environmental contexts, depending on the type of scenario, whether indoors or outdoors working environments. The aim of this study was to investigate the role that indoor and outdoor environments play in altering oxidative stress levels in workers in relation to the exposure to particles. Methods: 162 subjects were recruited; 62 were subjects working in indoor environments (13 employed in the handling of waste, 49 not exposed to this task), 100 subjects working in outdoor environments (65 employed in sweeping of the streets, 35 not exposed to this task). Oxidative stress was assessed by analysing 15-F2t-isoprostane concentrations in urine samples of all the recruited subjects. In addition, a questionnaire was administered to each to obtain information among which gender, age, BMI, smoking habits. Statistical analyses were done using SPSS and 15-F2t-Isoprostane concentrations were compared each other using the Kruskal-Wallis test. Results: The analyses showed a higher level of 15-F2t-Isoprostane in workers working in indoor environment when compared to workers working in outdoor environments (P&amp;#x3c;0.01). Furthermore, the employed in the handling of waste in indoors show the highest level of 15-F2t-isoprostane (P&amp;#x3c;0.05) while, subjects not exposed to this task in indoors, place themselves at intermediate 15-F2t-isoprostane levels. Conclusions: This study shows that higher levels of oxidative stress were found in both exposed and unexposed workers in indoor environments. Analysing the responses to the questionnaire, we also controlled tobacco smoke exposure because it may have a role in the redox imbalance recorded in workers. These results hypothesise that particle dilution in outdoor environments may be directly associated with lower levels of oxidative stress in the workers. Keywords: occupational exposure, environmental exposure, particle emissions.