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Mechanical Properties of Microbially Mineralized Soils under Freezing and Thawing Cycles
No full textTo investigate the stabilization effectiveness of microbially induced calcium carbonate precipitation on frost damage in subgrades within seasonally frozen regions, this study used subgrade soils from the Xige section of the Qinghai Tibet Railway around Qinghai Lake. Under varying numbers of grouting rounds, we examined the permeability characteristics, the thermal characteristics, and soil deformation under freezing and thawing cycles. The results show that, relative to the untreated specimens, the permeability coefficient of the specimens after 9 grouting rounds decreased by 2 orders of magnitude, and the thermal conductivity increased by 347.22%. After 7 freezing and thawing cycles, frost heave displacement decreased by 60.84% and the frost heave ratio decreased by 60.32%. The calcium carbonate content after 9 rounds increased by 245.4% compared with 1 round. Based on these results, microbially induced calcium carbonate precipitation can effectively enhance the engineering performance of the seasonally frozen subgrade around Qinghai Lake and provides a new approach for subgrade reinforcement in seasonally frozen regions
Analysis of the Current Situation of Science and Technology Innovation Platforms in China's Housing and Urban-Rural Construction Sector and Development Suggestions
No full textScience and technology innovation platform is an important carrier to carry out basic research, common key technology research and development of industry, transformation and industrialisation of scientific and technological achievements, and scientific and technological resources sharing service and other scientific and technological innovation activities according to the development of scientific frontiers, national strategic needs and industrial innovation and development needs, and it is an important part of the national and regional innovation system. This study employs a systematic literature review and analysis of publicly available official data from sources including the Chinese Ministry of Science and Technology, National Development and Reform Commission, Ministry of Education, and other relevant ministries, as well as university websites and official news releases. Data collection focused on the inventory, distribution, and management policies of various national and ministerial-level science and technology innovation platforms up to June 2023. In this paper, we systematically sort out the status quo of science and technology innovation platforms, analyse the existing problems of science and technology innovation platforms in the field of housing and construction, and put forward the development suggestions to further strengthen the construction and management of science and technology innovation platforms in the field of housing and construction, so as to serve the high-quality development of housing and urban-rural construction undertakings through science and technology innovation platforms as a hand
Identification of coal distribution based on drilling and geophysical logging: A case study from Samurangau, East Kalimantan
No full textCoal is one of the major energy resources, and its utilization is strongly influenced by the quality and spatial distribution of subsurface reserves. This study aims to identify the position, thickness, and distribution pattern of coal seams in the Samurangau area, Biu, Muara Samu District, Paser Regency, East Kalimantan Province. The analysis was carried out using drilling and geophysical logging data, focusing on gamma ray and density log responses from several shallow boreholes. The results reveal 13 coal seams, sequentially named seams 15 to 3 from top to bottom, with thicknesses ranging from 0.40 to 18.10 m and occurring at depths of 1.50-233.10 m. Splitting was observed in seams 9, 8, 4, and 3, while some seams also exhibit thinning. Overall, the seams show a Northwest-Southeast distribution trend with a general dip toward the Southwest. These findings provide essential information to support further exploration, geological modeling, and mine planning in the study area
Preliminary study on the characterization of geothermal fluids at Mount Jobolarangan (old Mount Lawu) western side and its implications for geothermal exploration
No full textMount Jobolarangan, also known as Old Lawu, is located on the southern side of Mount Lawu in Karanganyar, Central Java. This Research is crucial to understand the geothermal resource potential within it. The purpose of this study is to conduct a lithology and geochemical analysis of geothermal fluids to determine the characteristics of the fluids and their potential implications for geothermal exploration. The research method used is in the form of surface geological research, which is divided into field data analysis, petrography and geochemistry. The geochemistry method used in this research involves fluid (water and gases) geochemical sampling with AAS and XRF analysis. The study area contains andesite lava formed from volcanic activity that products by subduction with the temperature of magma forming in the range 1090°C - 1098°C. The geothermal manifestations in the study area are hot springs, which exhibit a bicarbonate fluid type. These geothermal fluids belong to the boundary zone between immature water and partial equilibrium, with a subsurface temperature ranging from 80°C to 120°C. The high magnesium content indicates that the geothermal fluid has been influenced by surface water and contact with surrounding rocks. The reservoir temperature is between 82°C and 86°C included in low-temperature geothermal system category
UAV-Based, AI-powered detection and heat mapping of potential mosquito breeding sites using YOLOv8
No full textMosquito-borne diseases, particularly dengue, remain a major public health challenge in tropical regions such as the Philippines. In 2024, dengue cases increased sharply nationwide, with the Davao Region reporting over 9,000 cases and rising mortality. Conventional mosquito control methods are often labor-intensive, costly, and difficult to sustain, especially in underserved communities. This study proposes an automated, real-time mosquito breeding site detection system integrating unmanned aerial vehicles (UAVs) with artificial intelligence-based image analysis and spatial heat mapping. A DJI Air 3 drone conducts aerial surveillance, while an OKdo Jetson Nano microcontroller runs dual YOLOv8 models: YOLOv8n for object detection and YOLOv8seg for water segmentation, optimized using NVIDIA TensorRT. The system detects potential breeding containers such as buckets, tires, and stagnant water, and generates heat maps to classify risk levels across barangays in Caraga, Davao Oriental. Field tests over 72 flights showed inference times of 56.1-114.8 ms and frame rates of 13.21-15 FPS. The model achieved 93.20% accuracy with high recall, precision, and F1 scores. Regression analysis indicated a strong correlation (R2 = 0.937) between detected breeding sites and dengue cases, confirming predictive validity and supporting its use for targeted public health interventions
Temperature and conductivity variation in the Ungaran geothermal area, Central Java, Indonesia
No full textThis study aims to examine variations in groundwater temperature and conductivity in the Ungaran geothermal area, which has unique geothermal characteristics. This area is known to have significant geothermal activity, which can affect the physical and chemical characteristics of groundwater. Temperature and electrical conductivity measurements were conducted at several spring locations. Data obtained from these groundwater temperature and conductivity measurements were analyzed to determine the relationship between the two parameters and for geological interpretation purposes. The results show significant variations in both temperature and groundwater conductivity in the Ungaran area. This finding indicates that temperature does not determine the value of groundwater electrical conductivity. This is evidenced by the very low correlation (1.4%) across all springs or 20.9% for geothermally controlled springs. Thus, these temperature and conductivity variations can be caused by various local geological conditions
Persistence-based Modes Inference
No full textWe address the problem of estimating multiple modes of a multivariate density using persistent homology, a central tool in Topological Data Analysis. We introduce a method based on the preliminary estimation of the -persistence diagram to infer the number of modes, their locations, and the corresponding local maxima. For broad classes of piecewise-continuous functions with geometric control on discontinuity loci, we identify a critical separation threshold between modes, equivalently interpretable in our framework in terms of modes' prominence, below which modes inference is impossible and above which our procedure achieves minimax optimal rates
Quantitative color profiling method using digital images to determine the phenotypic relationships of beetles in selected urban areas of Southern Philippines
No full textThe assessment and comparison of colors have historically relied on subjective methods, which may introduce potential inaccuracies specially comparing diverse coloration of insects such as beetles. In contrast, modern objective techniques frequently require expensive equipment and specialized knowledge. This study utilized beetle images to quantify their color patterns and assess phenotypic relationships among species. Beetle specimens were collected from selected urban regions in Southern Philippines, using opportunistic sampling. The specimens were then preserved in 70% ethyl alcohol and subsequently dissected. Under precisely controlled conditions, the elytron of 48 insects was photographed. The color values of the images were extracted and converted to Commission on Illumination, 1976 L*a*b* (CIELab) color space after calibration. Using cluster analysis, the color distance of the elytron images was compared across samples. Results showed that the average elytral coloration displays moderate darkness, a subtle reddish hue, and an appreciable infusion of yellowness. Furthermore, colorimetric analysis showed that elytron of sampled beetles displays two distinct color variations: (1) a moderate luminosity characterized by prominent reddish hues and evident yellow manifestation, and (2) a darker version with a subtle reddish undertone and faint yellow hints. The findings of this investigation showed potential use of digital images in objectively assess color patterns of beetles in urban environments
Study on Environmental Control Methods of the Anterior Room During the Limited Opening to the Public of Burnt Wall Paintings in the Main Hall of the Treasure House at Horyu-ji Temple
No full textThe Main Hall of Horyuji Temple was damaged by fire in 1949, not only in the building but also in the preserved wall paintings. The wall paintings that survived the fire damage are national important cultural properties and, because of concerns about deterioration, are stored together with the burnt parts in a non-air-conditioned treasure house in the precincts of the temple, which is not open to the public at present as a general rule. In the previous report, a research study was initiated to open the treasure house to the public, and the effects of heat and humidity on the stored items have been studied through annual temperature and humidity measurements and numerical simulations. Based on these findings, an anterior room was constructed in the treasure house and a heat pump desiccant dehumidifier was installed as a dehumidifier to reduce the effects of the outside air and prevent the introduction of moisture into the treasure house. This study reports the control performance of the anterior room and discusses future issues, with the aim of identifying appropriate environmental control measures and operational strategies for the anterior room during periods of limited opening to the public
Study on thermal mitigation of the balcony by green curtains in Japanese condominium
No full textIncreasing concerns over climate change, the pursuit of carbon neutrality has emerged as a key policy objective. Green infrastructure including “green curtains” is gaining attention due to its simplicity and effectiveness in urban thermal environments. Although previous research has focused on classrooms and urban spaces, there remains a lack of information on balconies, especially in new residential buildings. This study examines the thermal environment of a balcony and evaluates the effectiveness of green curtains on a recently constructed 8-storey apartment building in Tokyo. A thermal measurement survey was conducted from June to September 2025 using digital measurement instruments. The results indicate that the installation of green curtains led to measurable reductions in balcony temperature and improvements in occupant thermal comfort. These findings suggest that green curtains represent an effective, user-friendly strategy for enhancing thermal comfort in urban residential environments, offering practical implications for sustainable housing design