West Direction Research Articles

Spatiotemporal changes in the strain field in the Niigata–Kobe Tectonic Zone: long-term analysis using GNSS time series data

We analyzed the spatiotemporal changes in the displacement and strain fields in the Niigata–Kobe tectonic zone (NKTZ), central Japan, with temporal resolutions of one and 3 years, respectively, using Global Navigation Satellite System (GNSS) time series data provided by the Geospatial Information Authority of Japan (GSI) over a long period of time from 1997 to 2022. We also attempted to extract steady-state variations without assuming linearity, which have never been obtained. The results show that the contraction rates of the dilatation rate, maximum shear strain rate and principal strain rate when postseismic deformations associated with large earthquakes were removed were consistently greater in the northern part of the NKTZ than in the central and southern parts of the NKTZ, reaching a maximum absolute value of 5.1 × 10–6 of contraction in the accumulated dilatation and an accumulated maximum shear strain of 3.0 × 10–6 for the 26 year period except for the years 2011 and 2012. These results are considered to result from the continuous expression of the elastic deformation of the thick sedimentary layer in the Echigo Plain and the viscous deformation of the lower crust, in addition to the effects of subduction of the oceanic Pacific plate. For the maximum shear strain, the central part of the NKTZ also has relatively large values, which may be caused by lateral deformation due to creep along the Atotsugawa and Ushikubi Fault Zones. Unlike before the Mw 9.0 2011 Tohoku-Oki earthquake, after the event, the dilatation rate was lower in the east‒west direction, and the variation in the dilatation rate appeared to return to the preearthquake dilatation rates both in terms of the spatial patterns and amplitudes over time within several years. The short-wavelength component of the dilatation rate in the east‒west direction in the northern part of the NKTZ shows that the spatial variations in the dilatation rate were similar before and after the 2011 Tohoku-Oki earthquake at 37.0° N, indicating continuous contraction. However, at 37.5° N, the spatial distribution of the dilatation rate changed from before to after the occurrence of the earthquake, and the characteristic large contractions that were identified before the earthquake were not observed after the event. Furthermore, Mj 4.0 or greater earthquakes were relatively uniformly distributed in the southern and central parts of the NKTZ. On the other hand, in the northern part of the NKTZ, there was a seismic gap, especially in areas with high strain concentrations in the Echigo Plain, where only large deformations could be caused by the low elasticity in the thick sedimentary layer. These results might indicate that a large earthquake will occur in the seismic gap in the future. In addition, a relatively large number of past major destructive earthquakes have occurred in the northern part of the NKTZ. In this area, since the Eastern Margin Fault Zone of the Takada Plain has a relatively high probability of an earthquake occurring in the next 30 years, additional detailed investigations of this area are needed.

Adaptive Distributed Student’s T Extended Kalman Filter Employing Allan Variance for UWB Localization

This study proposes an adaptive distributed Student’s t extended Kalman filter (EKF) using Allan variance for ultrawide-band (UWB) localization. First of all, we model the state equation using the target’s position and velocity in east and north directions and the measurement equation by using distance between the UWB base station (BS) and the target object. Then, the adaptive distributed filter employs a federation structure: A local t EKF is designed to estimate the target’s position by fusing the distance between the UWB base station and the target object. The main filter fuses the local filter’s outputs and computes the final output. For the local t EKF, in order to overcome the problem that noise in the Kalman method is assumed to be white noise and difficult to adapt to practical application environments, the t distribution is used to model noise. Meanwhile, Allan variance is calculated to assist the local filter, which improves the adaptive ability. Experimental results show that the proposed method effectively enhances navigation accuracy compared to the distributed EKF.

T CrA has a companion. First direct detection of T CrA B with VLTI/MATISSE

T CrA is a Herbig Ae-type young star in a complex circumstellar environment; it includes a circumstellar disk, accretion streamers, jets, and outflows. It has long been suspected to be a binary. However, until now, there has been no direct detection of a companion. Here we present new VLTI/MATISSE L- and N-band observations of T CrA taken between 2023 May and 2024 August with the aim of testing the binary nature of the system. We modeled the data with a geometric model using the Python tool oimodeler . We detected a companion (T CrA B) with a projected separation of Δ r = 153.2 ± 1.2 mas (≈$23$ au) toward the west direction at a position angle of $275.4 ± 0.1 in 2024 May--August. Our results support that the companion has a nearly edge-on orbit that is highly misaligned with respect to the circumprimary disk. Such a configuration could cause warping and tearing of the disk around the primary, which has been proposed by recent studies. In the L band the companion is extended, with a full width at half maximum (FWHM) size of ∼$1$ au, suggesting that the emission comes from a disk around the secondary star. The companion flux is $0.2--0.3$ Jy in the L band, and $0.2--0.7$ Jy in the N band, accounting for $4--20%$ of the total emission at those wavelengths. The SED of the companion is compatible with thermal radiation of warm dust ($600--800$ K).

Application of variational Bayesian-based cubature information filter for UWB/INS tightly coupled positioning system

Abstract Accurate and reliable positioning is a crucial foundation for achieving sufficient autonomy and intelligence in positioning systems. The ultra-wideband (UWB) technology has significant potential for applications in the challenging and complex field of indoor positioning, and is often integrated with the inertial navigation system (INS) to enhance the overall performance of integrated positioning system. This paper proposes a novel variational Bayesian-based cubature information filter that enhances the positioning accuracy of tightly coupled UWB/INS navigation system. This approach aims to provide continuous and reliable navigation and positioning across various scenarios. The proposed integrated system applies the non-holonomic constraint to positioning in the elevation direction, thereby enhancing the system’s overall positioning accuracy and performance. Real-world experimental results demonstrate that the proposed system delivers continuous, accurate, and stable positioning. In UWB line-of-sight (LOS) scenario, the proposed system achieves root mean square errors (RMSEs) of 0.085 m, 0.091 m, and 0.125 m in the east, north, and horizontal directions, respectively; the corresponding errors in non-LOS (NLOS) scenario are 0.286 m, 0.237 m, and 0.372 m. Furthermore, when integrated with a scheme for mitigating NLOS errors, the proposed system demonstrates a significant enhancement in positioning accuracy. In conclusion, the experimental results effectively validate the proposed system’s effectiveness in achieving accurate and continuous positioning across various environments, demonstrating its application potential in complex scenarios.

Evaluation of the coordinated development of health resources, health service utilization, and the regional economy in China and analysis of influencing factors

ObjectiveThis study investigates the coupling coordination relationships and influencing factors of health resources, health service utilization, and regional economy in China, aiming to provide reasonable suggestions for promoting the coordinated development of medical and health services and regional economy.MethodsThe panel data from 2016 to 2021 on China’s health resources, health service utilization were analyzed concerning China’s health resources, health service utilization, and regional economy. These included the entropy weight method for index weight calculation, the synthesis level index for subsystem synthesis level calculation, a coupled coordinated development model, exploratory spatial data analysis, and a geographic detector model. These analytical approaches facilitated the examination of spatial and temporal variances, alongside the identification of driving factors influencing the coupled and coordinated development of health resources, health service utilization, and regional economy in China.ResultsThe findings reveal that (1) a high level of coupling exists among the three subsystems across all provinces in China. (2) Concerning the spatial pattern of coupling coordination, notable regional differences are observed in the degree of coupling coordination between health resource utilization, health service utilization, and regional economic development, with a noticeable decline from east to west and central regions positioned in between. (3) Regarding spatial evolution characteristics, an overall trend of higher levels is observed in the east and north compared to the west and south, indicating localized spatial clustering. In the south‒north direction, there is a parabolic rise followed by a decline from north to south. In the east‒west direction, there is an inverted “U” shaped curve with gradual strengthening from east to west. (4) The spatial disparities in synergetic development among health resource utilization, health service utilization, and the regional economy arise from multiple influencing factors interacting with each other. (5) Spatial variations are noted in the impacts of driving factors on coordinated development among health resource utilization, health service utilization, and the regional economy during different time periods.ConclusionRegional disparities primarily arise from various factors, such as healthcare visit frequency, healthcare human resource availability, and healthcare material resource allocation; moreover, these factors also vary geographically across different time periods. Strategic measures for medical care services and economic development should be formulated by each region based on its own circumstances to enhance economic benefits and achieve coordinated high-quality development among health resource utilization, health service utilization, and the regional economy.

STUDI HUBUNGAN ANTARA TIGA PARAMETER DENGAN MENGGUNAKAN MODEL GREENSHIELD, GREENBERG, UNDERWOOD DAN BELL PADA RUAS JALAN DR. SUDJONO KOTA MATARAM

Dr. Sudjono Road is a National Road in Mataram City which is included in the collector road class, which connects various activity centers, such as educational activities, offices, economy and others. This causes the traffic flow to increase, which has an impact on traffic speed and density. This study aims to analyze the relationship between three parameters, namely volume (Q), speed (V) and density (D) of traffic according to existing conditions and find out the model that best suits the road. In analyzing the mathematical relationship between the three main variables of traffic flow, the Greenshield, Greenberg, Underwood and Bell models were used. The results show that the most suitable model is the Greenshield model compared to the other three models. So from the Greenshield model, the relationship between volume (Q), speed (V) and density (D) is obtained for the Jalan Dr. Sudjono from the East direction obtained: (Vs-D): Vs= 47.263 - 0.613× D, (Q-D): Q= 47.263 ×D-0.613×D^2, (Q-Vs): Q= 77.074×Vs–1.631×Vs2 and from the West direction obtained: (Vs-D): Vs= 56.398 - 0.846×D, (Q-D): Q=56.398 ×D-0.846×D2, (Q-Vs): Q= 66.627×Vs-1.181×Vs2. Based on a model that is suitable for Jalan Dr. Sudjono, namely the Greenshield model, the traffic flow characteristics from the East are obtained: (Qm) = 910,694 pcu/hour, maximum speed (Vm)=23,632 km/h, maximum density (Dm) = 93,624 pcu/km, free flow speed (Vsff) = 47,263 km/h and density during traffic jams (Dj) = 77,074 pcu/km and from the west it is obtained: (Qm)= 939,403 pcu/hour, (Vm) = 28,199 km/hour, (Dm) = 33,313 pcu/km, (Vsff) = 56,398 km/hour and (Dj) = 66,627 pcu/km.

Compact Multi-Channel Long-Wave Wideband Direction-Finding System and Direction-Finding Analysis for Different Modulation Signals

This paper presents an optimized long-wave (10–300 kHz) wideband direction-finding system for scientific research. The antenna unit of the system comprises one vertical electric field sensor and two horizontal magnetic field sensors oriented in the north–south and east–west directions, respectively. The overall design prioritizes compactness, engineering feasibility, and ease of deployment, enabling the effective reception of long-wave radio signals within the 10–300 kHz range. The magnetic field sensitivity reaches 8fT/Hz@10kHz, while the electric field sensitivity achieves 3.2μV/m/Hz@10kHz. The overall sensitivity of the receiver is 1μV (300 Hz bandwidth, 10 dB signal-to-noise ratio). The synchronization accuracy of the system is within 10 ns. Theoretically, with a baseline length of 5 km and a signal incidence angle ranging from 9.9° to 170.1°, the direction finding error is less than 2°. Additionally, direction-finding methods for MSK and ASK modulated signals are analyzed. To evaluate the system’s actual performance, initial measurements were conducted in Qingdao, Shandong.

Application of Improved Fault Detection and Robust Adaptive Algorithm in GNSS/INS Integrated Navigation

In vehicle GNSS/INS integrated navigation, robust and adaptive algorithms have become one of the key technologies for achieving a comprehensive PNT due to their ability to control the gross errors of the observation model and dynamic model. The Sage–Husa algorithm is widely used in optimizing the Kalman filter due to its ability to estimate the observation or state covariance without prior information. However, the quality of observations in complex environments is prone to large fluctuations, so the averaging method is not suitable for dynamic navigation. To solve this problem, this article designs a double window structure and introduces a time-dependent fading weighted factor. At the same time, a logarithmic form factor constructor is proposed in order to avoid anomalies in the robust and adaptive factor. The traditional innovation adaptive filter is improved and turned into a multi-factor adaptive filter. In this paper, an improved fault detection algorithm is used to combine a robust algorithm with an adaptive algorithm to adapt to different gross errors in different scenarios. The experimental results of complex scenarios show that the position RMSE of the improved algorithm in the east, north, and height directions is 0.68 m, 0.71 m, and 1.05 m, respectively, which are reduced by 39.3%, 39.3%, and 70.3% compared to the EKF.

ScintPi measurements of low-latitude ionospheric irregularity drifts using the spaced-receiver technique and SBAS signals

Abstract. Previous efforts have used pairs of closely spaced specialized receivers to measure Global Navigation Satellite System (GNSS) signals and to estimate ionospheric irregularity drifts. The relatively high cost associated with commercial GNSS-based ionospheric receivers has somewhat limited their deployment and the estimation of ionospheric drifts. The development of an alternative, low-cost, GNSS-based scintillation monitor (ScintPi) motivated us to investigate the possibility of using it to overcome this limitation. ScintPi monitors can observe signals from geostationary satellites, which can greatly simplify the estimation of the drifts. We present the results of an experiment to evaluate the use of ScintPi 3.0 to estimate ionospheric irregularity drifts. The experiment consisted of two ScintPi 3.0 deployed in Campina Grande, Brazil (7.213° S, 35.907° W; dip latitude ∼ 14° S). The monitors were spaced at a distance of 140 m in the magnetic east–west direction and targeted the estimation of the zonal drifts associated with scintillation-causing equatorial spread F (ESF) irregularities. Routine observations throughout an entire ESF season (September 2022–April 2023) were made as part of the experiment. We focused on the results of irregularity drifts derived from geostationary satellite signals. The results show that the local time variation in the estimated irregularity zonal drifts is in good agreement with previous measurements and with the expected behavior of the background zonal plasma drifts. Our results also reveal a seasonal trend in the irregularity zonal drifts. The trend follows the seasonal behavior of the zonal component of the thermospheric neutral winds as predicted by the Horizontal Wind Model (HMW14). This is explained by the fact that low-latitude ionospheric F-region plasma drifts are controlled, in great part, by Pedersen-conductivity-weighted flux-tube-integrated zonal neutral winds. The results confirm that ScintPi has the potential to contribute to new, cost-effective measurements of ionospheric irregularity drifts, in addition to scintillation and total electron content. Furthermore, the results indicate that these new ScintPi measurements can provide insight into ionosphere–thermosphere coupling.

A Multipath Hemispherical Map with Strict Quality Control for Multipath Mitigation

The multipath effect is a critical factor that prevents the Global Navigation Satellite System (GNSS) from achieving millimeter-level positioning accuracy. A multipath hemispherical map (MHM) is a popular approach to achieving real-time multipath error mitigation. The premise of the constructed MHM model is that the residuals in the grid only contain multipath errors and noise without any outliers. However, when there are numerous obvious outliers in each grid, the traditional quality control method is unable to detect them effectively. Therefore, we propose a multipath hemispherical map with strict quality control (MHM-S) to mitigate multipath errors. This method first uses the maximum phase delay to eliminate obvious outliers. Then, the 3-sigma rule and F-test are applied to remove the remaining few outliers in the grid. After applying the proposed MHM-S method, the experimental results show that when the PRN20 satellite is affected by outliers, the standard deviation (STD) reduction rate of the MHM-S residuals is 12.03% compared with the residual STDs of the MHM model. In addition, we evaluate the capabilities of MHM-S with carrier phase observation (MHM-SC) and carrier phase and pseudo-range observation (MHM-SCP) models in multipath error mitigation. Especially in the east direction, the positioning accuracy of the MHM-SCP model is improved by 48% compared with the MHM-SC model.

Study on the Dynamic Evolution and Driving Forces of High-Quality Development of Coal Cities in China

To more intuitively demonstrate the locational distribution of spatial agglomeration of HQD (high-quality development) in China’s coal cities, this study uses the entropy value method, standard deviation ellipse, and geographic detector to investigate the law of dynamic evolution and driving factors of HQD in China’s coal cities from 2011 to 2020. The findings are as follows: (1) The HQD level of China’s coal cities is experiencing a positive trajectory, with the highest level of development in the east, followed by the regions located in the center and west of the country, and relatively low in the northeast. Throughout the “Twelfth Five-Year Plan” period, Suzhou made the greatest progress, while Fuxin had the greatest decline. Throughout the “13th Five-Year Plan” period, Xingtai and Handan made the greatest progress, while Qitaihe had the greatest decline. (2) The HQD level of China’s coal cities as a whole shows a northeast–southwest direction, the center of gravity shifts southward, indicating a concentration pattern. The eastern and central areas are oriented in a northwest–southeast direction; the center of gravity in the east shifts to the northwest, and the center of gravity in the middle shifts to the southeast; and both regions have a higher level of HQD in the east–west direction. The western and northeastern regions are in a northeast–southwest direction, with the center of gravity moving to the northeast: the western region shows a tendency toward diffusion, and the northeastern region shows an agglomeration trend. (3) Patent authorization per 10,000 people, foreign trade dependence, R&D investment intensity, and GDP per capita were important drivers for the HQD of China’s coal cities; The degree of government intervention is the best interaction factor, and the degree of opening to the outside world and the forest coverage rate are the best interaction objects.

A Multipath Mitigation Method for Significant Environmental Changes in Deformation Monitoring

A Multipath Mitigation Method for Significant Environmental Changes in Deformation Monitoring

In Situ Dynamic Characteristic Test and Seismic Performance Analysis of Hybrid Brick‐Concrete and Timber Structure of Historic and Cultural Architectures

ABSTRACTIn order to study the dynamic characteristics and seismic performance of the hybrid brick‐concrete and timber (HBCT) structure, an in situ dynamic characteristic test was carried out, and peak picking method was used to calculate natural frequencies, damping ratios, and vibration modes. Considering semi‐rigid mechanical characteristics, a finite element model of the hybrid structure was established, and the calculation results agreed well with the test results. Kobe, El Centro and an artificial ground motion were input for displacement and acceleration response analysis. A set of fifteen ground motion records were selected, and incremental dynamic analysis and seismic fragility analysis were conducted. Results show that the first and second natural frequencies of the HBCT structure are 4.327 and 4.375 Hz, and the vibration modes are translation in the east–west direction and in the north–south direction, respectively. Taking the Kobe ground motion as an example, the maximum displacement of the pillar top of the second‐floor timber structure is 6.12 times that of the pillar top of the first‐floor brick‐concrete structure. The peak inter‐structural layer drift of 1/155 is less than the standard limit. Dynamic coefficients of the overall structure are less than 1, which indicates that the HBCT structure exhibits good shock absorption performance. The performance at different seismic intensities is in accordance with the “Three‐level and Two‐stage Seismic Fortification Goals,” which means no damage under minor earthquake, repairable damage under moderate earthquake, and no collapse under large earthquake.

Practical analysis of using PPPH and raPPPid for Precise Point Positioning in Europe

Abstract Assessing the reliability of using open-source software packages for post-processing of the Global Navigation Satellite System (GNSS) is essential since GNSS modernization has the potential to assist satellite navigation users. The purpose of this study is to evaluate the accuracy of using two MATLAB-based programs, raPPPid and PPPH for precise point positioning in Europe. Data from 12 MGEX stations over two days were used, with one day dedicated to each of the 6 stations and a 30-second observation interval. The data were post processed by PPPH and raPPPid programs and a comparison was made to evaluate the results accuracy produced by each software and the ones acquired from MGEX stations. Convergence time was also estimated. By comparing the root mean square error (RMSE) values for North, East and Up directions estimated by PPPH and raPPPid, it was found that raPPPid gives more accurate results where the RMSE in N direction estimated by raPPPid varied from 0.5 cm to 1.9 cm; however, RMSE in N direction estimated by PPPH varied from 0.7 cm to 2.8 cm. RMSE in E direction estimated by raPPPid varied from 0.4 cm to 3.3 cm, but RMSE in E direction estimated by PPPH varied from 0.5 cm to 3.7 cm. RMSE in Up direction estimated by raPPPid varied from 0.8 cm to 5.2 cm, while RMSE in Up direction estimated by PPPH varied from 0.9 cm to 5.5 cm. 3D Positioning error was also estimated by both software and it was found that the 3D positioning error estimated by raPPPid varied from 0.2 cm to 2.2 cm, whereas the 3D positioning error estimated by PPPH varied from 0.9 cm to 4.1 cm. Finally, the average convergence time achieved by raPPPid was 16.5 minutes, while the average convergence time achieved by PPPH was 32 minutes.

A method for monitoring three dimensional surface deformation in mining areas combining SBAS-InSAR, GNSS and probability integral method

In the process of mineral resource extraction, monitoring surface deformation is crucial for ensuring the safety of engineering and ground infrastructure. Monitoring complete three-dimensional surface deformation is particularly significant. Traditional synthetic aperture radar (InSAR) technology provides deformation components only along the line of sight (LOS) and often lacks sufficient effective data in vegetation-covered mining areas and mining subsidence centers. To address this, this study proposes a method (SBAS-PIM) that combines SBAS-InSAR with the probabilistic integral method (PIM). This method leverages high-coherence points in mining areas and GNSS data from vegetation-covered regions to invert the parameters required by PIM, thus obtaining three-dimensional surface deformation results. The proposed method allows for the acquisition of three-dimensional deformation data with fewer InSAR points and GNSS data, significantly reducing labor costs and addressing the gap in InSAR monitoring of three-dimensional surface deformation in densely vegetated areas. Additionally, it accounts for the mutual influence of multiple adjacent working faces. Finally, through the application to a mining area in Heze, China, the maximum displacements in the vertical, east–west, and north–south directions were obtained as −2011, −418, and − 281 mm, respectively. The correlation coefficients between the vertical and east–west directions and GNSS data were both greater than or equal to 0.9, indicating that this method can effectively monitor the three-dimensional surface deformation of the mining area.

Analysis of the Coupling Coordination and Spatial Difference Between Economic and Ecological Environment: A Case Study of China

This study adopts a sustainable development perspective to examine the economic and ecological coordinated progression and spatial disparities across 30 regions in China from 2011 to 2022. Firstly, detailed analysis of CCD reveals that coordination between the ES (economic subsystem) and the EES (ecological environment subsystem) in 30 regions of China has been rising annually. However, the overall level of coordination remains relatively limited. Second, the analysis of kernel density estimation (KDE) shows that the coordination degree between ES and EES across various regions exhibits considerable variability, with the disparity becoming increasingly pronounced. Third, trend surface (TS) analysis indicates that there exist regional variations in the degree of coordination between ES and EES. Specifically, the east experiences an upward trend, while the west exhibits a downward trend. Similarly, the south shows an increase, whereas the north demonstrates a decrease. With ongoing development, it has been observed that the coordination degree remains relatively stable in the east–west direction; however, the disparity between the north and south is increasing. Fourth, an analysis of global Moran’s I reveals a pronounced positive spatial autocorrelation. Finally, the analysis of local Moran’s I reveals that Jiangsu, Fujian, Anhui, and Jiangxi provinces exhibit significant high–high clusters, while the three regions of Xinjiang, Gansu, and Ningxia have always been low–low clusters.

Analisis Penentuan Tarif Jalan Tol Cibitung – Cilincing Menggunakan Metode Pendekatan Ability To Pay (ATP) dan Willingness To Pay (WTP)

Transportation infrastructure and networks play a very large role in serving the movement of human activities, goods and services. Therefore, it is necessary to have a transportation network with good conditions and service levels that can connect each other between regions quickly and easily. One solution to overcome this condition is to build toll roads to pass traffic safely, comfortably, smoothly and even economically. The Cibitung-Cilincing toll road section is part of the Jakarta Outer Ring Road II (JORR II) located in a North-South direction corridor, starting from the Cibitung Interchange on the Jakarta - Cikampek Toll Road KM 25, heading north in Babelan sub-district and continuing to West direction meets the North Outer Ring at the Cilincing interchange. This research was conducted as a reference and recommendation for the current Cibitung - Cilincing toll road tariff. The number of respondent samples used was 100 respondents in class 1 vehicles, and 120 respondents in class 2 vehicles. Data collection was carried out by distributing questionnaires and direct interviews related to the socio-economic characteristics and travel characteristics of the respondents. The tariff recommendation that will be obtained is by using the Ability to Pay (ATP) and Willingness to Pay (WTP) approaches. The results of the study can be seen the socio-economic characteristics and travel characteristics of toll road users. The average ATP value in group 1 was Rp. 2,233/Km and for group 2 is Rp. 2,408/Km. The average WTP value in group 1 is Rp. 1,863/Km and for group 2 is Rp. 2,775/Km

Intelligent Algorithm-Based Modeling of Lighting and Thermal Environment Balance in Green Buildings

Abstract With the vigorous implementation of economic development and energy saving and emission reduction policies, people have higher requirements for both indoor comfort and building energy saving. This paper discusses the green transformation of buildings with balanced lighting and thermal environments, adopts the dynamic lighting evaluation standard and the indoor thermal comfort evaluation index PMV as the evaluation indexes of the light and heat environments, and constructs a multi-objective optimization model of light and heat environments in green buildings based on the non-dominated elite genetic algorithm NSGA-II and multi-objective optimization method, in order to achieve the goals of the green transformation with balanced lighting and heat environments and energy saving and environmental protection. The results of the bi-objective optimization of the light and heat environment show a stronger constraint relationship, which is evident in the east direction and weaker in the south direction. The dual-objective optimization results in the south direction are more stable, and the energy savings effect is over 74%. The energy saving and light environment improvement effects of the east-oriented optimal solution are overall lower than those of the south-oriented case, which shows the importance of building orientation. In addition, comparing the optimization results of heat and light thermal environment under 8 working conditions, it can be seen that under the premise of taking into account the thermal environment and indoor lighting, 40% lighting area ratio + roof local exhaust is the most effective optimization measure, at this time, the indoor vertical temperature difference all day peak can be reduced to about 8 ℃. In this paper, the characterization and optimization study of green building lighting and thermal environment is carried out, with a view to providing data support for the optimal design of the light and heat environment of green buildings in actual projects.

Transformer-Based Ionospheric Prediction and Explainability Analysis for Enhanced GNSS Positioning

This study aims to investigate the impact of ionospheric models on Global Navigation Satellite System (GNSS) positioning and proposes an ionospheric prediction method based on a Transformer deep learning model. We construct a Transformer-based deep learning model that utilizes global ionospheric maps as input to achieve spatiotemporal prediction of Total Electron Content (TEC). To gain a deeper understanding of the model’s prediction mechanism, we employ integrated gradients for explainability analysis. The results reveal the key ionospheric features that the model focuses on during prediction, providing guidance for further model optimization. This study demonstrates the efficacy of a Transformer-based model in predicting Vertical Total Electron Content (VTEC), achieving comparable accuracy to traditional methods while offering enhanced adaptability to spatial and temporal variations in ionospheric behavior. Furthermore, the application of advanced explainability techniques, particularly the Integrated Decision Gradient (IDG) method, provides unprecedented insights into the model’s decision-making process, revealing complex feature interactions and spatial dependencies in VTEC prediction, thus bridging the gap between deep learning capabilities and explainable scientific modeling in geophysical applications. The model achieved positioning accuracies of −1.775 m, −2.5720 m, and 2.6240 m in the East, North, and Up directions respectively, with standard deviations of 0.3399 m, 0.2971 m, and 1.3876 m. For VTEC prediction, the model successfully captured the diurnal variations of the Equatorial Ionization Anomaly (EIA), with differences between predicted and CORG VTEC values typically ranging from −6 to 6 TECU across the study region. The gradient score analysis revealed that solar activity indicators (F10.7 and sunspot number) showed the strongest correlations (0.7–0.8) with VTEC variations, while geomagnetic indices exhibited more localized impacts. The IDG method effectively identified feature importance variations across different spatial locations, demonstrating the model’s ability to adapt to regional ionospheric characteristics.

Subsurface Characterization and Revealing Geometry of the Baribis Fault in the Eastern Part of West Java Using Long-Offset Resistivity Tomography

The Baribis Fault is an important active fault in West Java, Indonesia. This fault has recently attracted the attention of many parties since some fault segments pass through densely populated areas, raising the risk of shallow earthquakes. The long-offset resistivity tomography method was applied to image the active Baribis Faults. This method clearly showed the subsurface geometry, including the contact characteristics of the Baribis Fault near the subsurface. The long-offset resistivity tomography surveys were acquired using multi-electrodes and multi-nodes, and the data acquisition was wirelessly controlled via a WiFi connection. The pole–dipole resistivity tomography image shows a 35∘ dip overhang structure of the Baribis thrust fault near the Jatigede area in Middle Eastern West Java, with a strike fault segment in a relative East–West direction. However, the other long-offset tomography images in northeastern West Java, near the Conggeang–Sumedang area, show the oblique thrust fault phenomena of the Baribis Fault with a strike in the Northeast–Southwest direction. The stress caused by the Cimandiri–Lembang regional strike–slip fault likely influences the dynamics of the Baribis Fault in the close area of Sumedang.