esa-sceva/satcom-chunk-collection huggingface dataset:
## 6 Synergism Between Algorithms and Smart City Optimization
### The Application Effect of Algorithm Collaboration in Real Estate Management in Smart City
In addition, combined with spatiotemporal data analysis, urban development trends can be predicted, providing scientific guidance for future infrastructure construction and public service facility layout and avoiding resource waste [66]. Secondly, the application of data analysis algorithms helps to explore the potential demand of the urban real estate market and provides a basis for market regulation. By analyzing real estate transaction data, rental prices, and other information, we can understand the market supply and demand situation, provide support for the government in formulating differentiated regulatory policies, and encourage resources to flow to more efficient areas. At the same time, this also helps to guide the rational investment of social capital and stimulate market vitality. Furthermore, the synergy of multi-source data fusion and analysis algorithms in real estate management helps to improve the operational efficiency of urban infrastructure. For example, through intelligent analysis algorithms, traffic flow, energy consumption, and other data can be monitored and analyzed in real time, providing strong support for infrastructure planning, construction, and management and achieving optimal resource allocation. In addition, algorithm synergy is also of great significance in optimizing the urban ecological environment [67]. Combined with environmental monitoring data, land use data, etc., the quality of the urban ecological environment can be evaluated, and a decision-making basis can be provided for environmental protection and governance. By rationally adjusting land use methods and optimizing ecological space layout, it is helpful to improve the quality of the urban environment and achieve sustainable development.
# WUE and CO2 Estimations by Eddy Covariance and Remote Sensing in Different Tropical Biomes
###### Abstract  
The analysis of gross primary production (GPP) is crucial to better understand CO2 exchanges between terrestrial ecosystems and the atmosphere, while the quantification of water-use efficiency (WUE) allows for the estimation of the compensation between carbon gained and water lost by the ecosystem. Understanding these dynamics is essential to better comprehend the responses of environments to ongoing climatic changes. The objective of the present study was to analyze, through AMERIFLUX and LBA network measurements, the variability of GPP and WUE in four distinct tropical biomes in Brazil: Pantanal, Amazonia, Caatinga and Cerrado (savanna). Furthermore, data measured by eddy covariance systems were used to assess remotely sensed GPP products (MOD17). We found a distinct seasonality of meteorological variables and energy fluxes with different latent heat controls regarding available energy in each site. Remotely sensed GPP was satisfactorily related with observed data, despite weak correlations in interannual estimates and consistent overestimations and underestimations during certain months. WUE was strongly dependent on water availability, with values of 0.95 gC kg-1 H2O (5.79 gC kg-1 H2O) in the wetter (drier) sites. These values reveal new thresholds that had not been previously reported in the literature. Our findings have crucial implications for ecosystem management and the design of climate policies regarding the conservationof tropical biomes, since WUE is expected to change in the ongoing climate change scenario that indicates an increase in frequency and severity of dry periods.  
Keywords:gross primary production; evapotranspiration; water use efficiency
# Robust Kalman Filter Aided GEO/IGSO/GPS Raw-PPP/INS Tight Integration
## 2 Methods
### Test Description  
The test area was around 1200 \(\times\) 1200 m\({}^{2}\) large and was approximately 20 kilometers away from the reference station. The whole test lasted for about 1.4 h, as shown in Figure 4. With such a short base-line, the smoothed solutions from GPS + BDS RTK/INS (with use of the navigation grade IMU) tight integration were used as the reference values to validate the proposed method. During the test, the vehicle moved approximately along the directions of south-north and east-west with a speed of within 13 m/s. The heading angle changed periodically around 0, 90, 180, 270, and 360\({}^{\circ}\), which led to the '#' shape route of the mission. The undulant test area could improve the observability for gyro error estimation and further improve the performance of PPP/INS tight integration. Shown in Figure 5 is the visible satellite number during the mission. From Figure 5a, it is clear that 12 GPS satellites and 7 BDS satellites were observed (including 3 IGSO satellites (C7, C8, C10) and 4 GEO satellites (C1, C2, C3, C4)). The visible satellite number under different combinations and the corresponding position dilution of precision (PDOP) value were plotted in Figure 5b. From the statistics, the average visible satellite numbers were 8.6, 12.4, 11.6, and 15.4 for GPS, GPS + GEO, GPS + IGSO, and GPS + GEO + IGSO, respectively, and the corresponding PDOP were 2.1, 1.9, 2.0, and 1.7. Therefore, the use of both GEO and IGSO can enhance GPS' observing condition and the corresponding geometry structure.  
In the data processing, both PPP and PPP/INS tight integration modes were adopted and the EKF and R-EKF were used as the estimators. The un-differenced and un-combined phase and code observations from GPS on L1 and L2 frequencies and BDS on B1 and B2 frequencies were processed by setting the cut of elevation angle to 10\({}^{\circ}\). The final precise satellite products of 300s-orbit and 30s-clock of multi-GNSS from German Research Centre for Geosciences (GFZ) were adopted. The elevation dependent weight function [6] and the equivalent weight function [39] in Equation (26) were used in normal- and robust-EKF. In the analysis phase, the first five-minute solutions were excluded because of the convergence time in both PPP and PPP/INS tight integration.  
\begin{table}
\begin{tabular}{c c c c c c} \hline
**IMU Sensors** & **Gyro Bias (\({}^{\circ}\)/h)** & **Accelerometer Bias (mGal)** & **Forward (mm)** & **Right (mm)** & **Down (mm)** \\ \hline Navigation Grade & 0.001 & 25 & \(-\)122.0 & 613.1 & \(-\)109.0 \\ Tactical Grade & 0.5 & 500 & 114.0 & 429.0 & \(-\)151.5 \\ \hline \end{tabular}
\end{table}
Table 1: Parameters of IMU sensors and lever-arm of receiver antenna with respect to IMU sensors.  
Figure 4: Trajectory in navigation frame (**a**) and the 3D velocity and movement direction (**b**) of the vehicle.
## 2 Model of Beam-Column Subassemblage
### Deformation Compatibility Condition  
Once the main crack opens at the beam-column interface, for arbitrary section in the PC zone, compressive strain is generated from the ultimate compression fibers to the neutral axis. As an accumulation of the compressive strain in all sections within the PC zone (\(l^{\prime}\)), the axial shortening \(\Delta_{c,xx}\) occurs at the extreme compression fiber of the beam end. In addition, the prestress of tendons causes an additional concrete axial shortening \(\Delta_{c0}\) at the beam end, which is equal to the product of the initial concrete compressive strain \(\varepsilon_{c0}\) and the length \(l^{\prime}\) of the PC zone. As mentioned in Section 2.1, the opening distance \(\delta_{d,tp}\) equals the elongation of the tensile side tendon, while the concrete axial shortening \(\Delta_{c,tp}\) equals the shortening of the compressive side tendon. Based on the deformation compatibility conditions and the plane section assumption of the concrete cross-section at the beam end, as shown in Figure 3, the concrete axial shortening \(\Delta_{c,tp}\) at the compressive side tendon position and the opening distance \(\delta_{d,tp}\) at the tensile side tendon position can be expressed as Equations (3) and (4).  
\[\Delta_{c,tp}=\Delta_{c,xx}\frac{x_{n}-(D-d_{t})}{x_{n}}-\varepsilon_{c0}l^{ \prime}=(\varepsilon_{t0}-\varepsilon_{t,c})l_{t} \tag{3}\]  
\[\delta_{d,tp}=\Delta_{c,xx}\frac{d_{t}-x_{n}}{x_{n}}+\varepsilon_{c0}l^{ \prime}=(\varepsilon_{t,t}-\varepsilon_{t0})\;l_{t} \tag{4}\]  
where \(D\) is the beam depth, \(d_{t}\) is the distance between the extreme compression fiber and the tendon position on the tensile side, \(\varepsilon_{t,c}\) and \(\varepsilon_{t,t}\) are the tendon strains on the compressive and tensile sides. \(\varepsilon_{t0}\) is the initial tensile strain of tendons due to the pre-tension force, and \(\varepsilon_{c0}\) denotes the initial compressive strain of the concrete caused by the same reason. The total length of the partial tendons is \(l_{t}\). The tendon deformations can be calculated by multiplying the tendon strains with \(l_{t}\). By solving Equations (3) and (4), \(\varepsilon_{t,c}\) and \(\varepsilon_{t,t}\) can be expressed as Equations (5) and (6).  
\[\varepsilon_{t,c}=-\frac{x_{n}-(D-d_{t})}{x_{n}l_{t}}\Delta_{c,xx}+\frac{ \varepsilon_{c0}l^{\prime}}{l_{t}}+\varepsilon_{t0} \tag{5}\]  
Figure 6: Force equilibrium condition at beam end.  
\[\epsilon_{t,t}=\frac{d_{t}-x_{n}}{x_{n}I_{t}}\Delta_{c,ex}+\frac{\epsilon_{c0}l^{ \prime}}{I_{t}}+\epsilon_{t0} \tag{6}\]
# Mobile Robot for Security Applications in Remotely Operated Advanced Reactors
## 4 Mobile Robots Categories
### Water-Based/Unmanned Water Vehicles  
From their origins in the 1950s to the present day, the field of unmanned underwater vehicles (UUVs) has significantly expanded. They have been employed in various tasks, ranging from bomb detection and recovery to underwater exploration. Initially, these robots were primarily used for military and scientific purposes, but they have now found widespread applications in civilian domains, including recreational use.  
Underwater robotics has evolved alongside manned underwater vehicles, but recent decades have witnessed the development of more cost-effective robots or UUVs. These robots have been optimized and deployed for a wide range of applications, contributing to the sustainable development of our planet. Understanding the marine environment's dynamics holds critical importance for humanity's future survival. Consequently, researchers have been committed to creating increasingly efficient unmanned vehicles capable of performing underwater work, maintenance, and exploration of ever-deeper marine realms [57].  
Figure 10: Representation of a UAV and an intrusion outside of the detection area [55].  
Likewise, research on autonomous boats, also known as unmanned surface vehicles (USVs) (Figure 11), in disaster management (DM) is widespread across multiple publications, often covering various unmanned vehicles under the category of unmanned marine Vessels (UMV). These vehicles are employed in disaster response and management, which encompass a range of actions. These actions are contingent on prior preparation and response capabilities, and they take place in either challenging emergency conditions or more favorable preparation stages [58].  
Plastic use is increasing without proper regulation in many countries, and this is causing toxins that harm the environment and human health, potentially leading to issues like cancer, birth defects, and immune system problems. Most of these plastics, through the river, ultimately end up in the ocean, leading to life-hazardous situations for marine animals. Research [60] was conducted where the researchers designed a prototype of an unmanned floating waste-collecting mobile robot that was able to collect trash weighing up to 10 kg and clean an area of about 3000 square centimeters, drawing only 45 watts from the battery.
## 2 Antenna Design Stages
### Simulation and Optimization  
After determining the initial patch dimensions, the antenna design was modeled and simulated using CST Studio Suite, a widely recognized electromagnetic simulation tool that is extensively used in high-frequency antenna development. The primary objective was to achieve robust dual-band operation at 28 GHz and 38 GHz while optimizing critical performance parameters, such as S\({}_{11}\), gain, radiation efficiency, and directivity.  
To enhance the accuracy of the simulation and account for real-world implementation factors, an SMP connector was integrated into the model using Antenna Magus software 2022 ([https://www.3 ds.com/products/simulia/antenna-magus](https://www.3 ds.com/products/simulia/antenna-magus), accessed date 16 February 2025). This addition enabled a more precise evaluation of the connector-induced effects, which are often overlooked but can significantly impact antenna performance at mmWave frequencies. The incorporation of the connector allowed for a more realistic assessment of impedance matching, signal integrity, and potential loss mechanisms.  
During the optimization phase, various design parameters were systematically adjusted to improve the performance metrics. A detailed parametric analysis was conducted to examine the influence of key geometrical and material properties, including the following:  
* Patch dimensions: The patch dimensions were modified iteratively to optimize the impedance matching and enhance the radiation efficiency.
* Substrate thickness and dielectric constant: Analyzed to balance gain enhancement with minimal losses, ensuring improved overall efficiency.
* Feed line configuration: Optimized for better impedance matching and reduced reflection coefficients.
* Ground plane modifications: These modifications were performed to fine-tune the radiation characteristics and improve the bandwidth.  
An in-depth sensitivity analysis guided the iterative optimization process to evaluate the antenna's resilience against minor manufacturing tolerances. This step is critical for ensuring minimal deviations due to fabrication inconsistencies. The final design exhibited significantly improved S\({}_{11}\) values, increased gain, and a more stable radiation pattern across the target frequency bands.  
By combining CST-based full-wave simulations with targeted parametric optimizations and connector integration studies, this research presents a high-performance dual-band microstrip antenna capable of delivering superior results in next-generation wireless communication applications.
# Effects of Shading on the Growth and Carbon Storage of _Enhalus acoroides_
## 4 Discussion
### Response of seagrass to Light Restoration  
After the restoration of light, the chlorophyll contents of _E. acoroides_ increased compared to those in the shading period, providing a favorable material basis for its photosynthesis under suitable light conditions. However, the physiological recovery was not reflected by the leaf morphology, shoot density or biomass. During the period of light restoration, the leaf and biomass of _E. acoroides_ remained reduced. Similar differences were observed in the growth and physiological responses of _Amphibolis griffithii_ and _Z. marina_ to restored light [13; 46]. This may be related to the seasonal growth of seagrass. In addition, the growth of _E. acoroides_ during the period of light restoration may be limited by typhoons. However, the more important reason is that long-term light stress may have a devastating effect on the growth of seagrass and that recovery would be difficult in the short term even when the stress is removed. Future increases in the photosynthetic rate may be effective in alleviating the damage caused by the pre-light-stressed environment, but long-term light reduction will affect photosynthesis and photomorphic construction, eventually leading to death. The sediment carbon of _Posidonia australis_ also increased significantly after restoration compared to the disturbed period [47]. This shows that a suitable growth environment is conducive to promoting the accumulation of organic matter in seagrasses, thereby increasing their CO\({}_{2}\) sequestration capacity.
# A Review of Lithium-Ion Battery Fault Diagnostic Algorithms: Current Progress and Future Challenges
## 2 Types of Fault in the Li-Ion Battery System
### External Battery Faults
#### 2.2.3 Cell Connection Fault  
Battery or cell connection fault is caused by the poor electrical connection between the cell terminals, as the terminals may become loose from vibration or corroded by impurities over time [39].  
When this fault occurs, the cell resistance can increase drastically, leading to cell imbalance due to uneven current, or overheating of the faulty cell [40]. This type of fault is simple to detect with voltage and temperature sensors, but if left unresolved, it could lead to more severe consequences, such as external short circuit or thermal runaway.
## 4 Discussion
### Research Limitations  
The research presented in this study has several limitations that should be acknowledged. First, the reliance on data from the Web of Science may not capture the full scope of scientific publications, particularly those in non-English languages or from emerging research communities that are less represented in this database. This could lead to an incomplete picture of global research productivity.  
Another limitation is the potential overemphasis on economic factors such as GNI per capita and research spending. While these are significant predictors of scientific output, other important factors like cultural influences, specific national innovation policies, and the structure of research institutions may also play crucial roles but were outside the scope of this study.  
Potential biases in the publication data, such as self-citation practices or the varying impact of conferences versus journals in different fields, could affect the results. Additionally, while the study uses the Augmented Human Development Index (AHDI), this measure may miss other influential factors such as the quality of education, research infrastructure, and specific government policies on technology and innovation.  
The correlations identified in the study do not establish causal relationships, leaving room for further investigation into the causality between the variables and scientific productivity. Moreover, the rapidly evolving nature of the fields of blockchain, privacy, and cybersecurity means that the study may not fully capture the latest developments and trends.
## 4 Conclusions  
This paper presents a novel joint phase-frequency distribution manipulation method for multi-band phased array radar based on optical pulse. The proposed method enables distributed control of both frequency conversion and phase shifting across multiple bands within a unified hardware framework. The experiments demonstrate the generation, transmission, reception, and data fusion of four-band signals (S, X, Ku, K) with a total bandwidth of 4 GHz using a four-element phased array. Multi-band data fusion improves range resolution by nearly fourfold. Channel interleaving demonstrates potential for expanding the system bandwidth and the number of bands. However, the scalability of channel interleaving is fundamentally constrained by the spectral resources of the optical frequency combs. Broadband comb expansion via supercontinuum sources or spectral shaping can address the spectral resources limitations. The integration of optical pulse sources remains a key challenge for system-level practicality. Fortunately, advancements in on-chip optical pulse source technologies are expected to resolve the integration hurdle, thereby enabling broader band expansion and feasible radar implementation. Integrating this multi-band coherent architecture with advancing AI technologies holds promise for  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Metric** & **This Work** & **RF Radar 1** & **Photonic Radar** \\ \hline \multirow{2}{*}{Number of Bands} & \multirow{2}{*}{S/X/Ku/K} & X/P [20] & X [32] \\  & & X/Ka [21] & Ka [33] \\ \multirow{2}{*}{Total Bandwidth} & \multirow{2}{*}{4 GHz} & 2.02 GHz [20] & 450 MHz [32] \\  & & 3 GHz [21] & 4 GHz [33] \\ \multirow{2}{*}{Range resolution} & \multirow{2}{*}{3.85 cm} & 10 cm [20] & 1.5 m [32] \\  & & 10 cm [21] & 4.2 cm [33] \\ \hline \hline \end{tabular}  
* *  
realizing software-defined intelligent sensing systems, which can enable comprehensive environmental perception in complex scenarios.  
Conceptualization, D.Z.; methodology, D.Z. and N.Q.; software, D.Z. and Y.L.; validation, D.Z., Y.L. and P.L.; formal analysis, R.Q.; data curation, D.Z.; writing--original draft preparation, D.Z.; writing--review and editing, N.Q. and W.Z.; visualization, D.Z.; supervision, N.Q.; project administration, W.Z.; funding acquisition, W.Z. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the National Natural Science Foundation of China (T2225023, 62205202), the Shanghai Sailing Program (22 YF1420200) and the Shanghai Aerospace Technology Renovation Fund (USCAST2022-37).  
The data that support the findings of this study are available from the corresponding author upon reasonable request.  
The authors declare no conflicts of interest.
# Ionospheric Narrowband and Wideband HF Soundings for Communications Purposes: A Review
## 2 Ionosphere Characteristics  
In this section we detail the physical characteristics of the ionosphere that influence the propagation of the electromagnetic signal, and the analyzes that, from a communications point of view, can be performed to expand the knowledge of a specific ionospheric channel for the propagation of telecommunication signals.
# Seismic Performance Evaluation of Steel Buildings with Oil Dampers Using Capacity Spectrum Method
###### Abstract  
This study proposes a capacity spectrum Method (CSM)-based procedure to estimate the maximum seismic performance of steel buildings passively controlled with bilinear oil dampers. In the proposed CSM, the maximum seismic response of a building was estimated, in the acceleration-displacement response spectrum, as the intersection between the capacity curve and the damping-adjusted demand curves, using the equivalent linearization method. The building equivalent damping ratio was determined by the sum of the inherent damping, and the square root of sum of squares (SRSS) of the hysteretic damping and the viscous damping of the supplemental oil devices. The calculation steps of the proposed CSM are explained in detail based on the equivalent single degree of freedom (ESDOF) system, and its accuracy was examined by comparison with time history analysis (THA) results. Two model steel buildings of 4 and 10 stories, uniformly equipped with oil dampers along the height, were subjected to six selected earthquake ground motions scaled to be compatible with Level-2 earthquakes, as defined in the Japanese Building Standard Law. The seismic performance of the buildings was estimated by the proposed CSM procedure and compared with the results of nonlinear THA in terms of the maximum story displacements and the shear forces. It was observed that the proposed CSM scheme provided a satisfactory accuracy to assess the maximum nonlinear response of steel buildings passively controlled with oil dampers.  
b 2021112687. [[https://doi.org/10.3390/app11062687](https://doi.org/10.3390/app11062687)]([https://doi.org/10.3390/app11062687](https://doi.org/10.3390/app11062687))  
1  
bilinear oil damper; steel structure; capacity spectrum method; passively controlled buildings