esa-sceva/satcom-chunk-collection huggingface dataset:
# A Review-Unguided Optical Communications: Developments, Technology Evolution, and Challenges
## 6 Contemporary Developments with UOC Technology
### FSO and VLC with Energy Harvesting
A concept of power transmission and EH, only in the absence of an ambient source, was proposed and an experiment was conducted using red light (five laser diodes of 50 mW each) links. Usually, EH is performed from ambient light during its availability. The harvested energy is collected by collimation lenses and then focused into a solar panel made of crystalline silicon. This type of configuration of an EH system increases the collection aperture and, as demonstrated in the experiment in [484], maximizes the collected power to 10.4 mW instead of 0.12 mW. The installation of several optical sources and receivers close to each other can potentially provide several services simultaneously. For example, the installation of an LED near the computer or suitable electronic gadgets can provide wireless lighting, wireless internet access, and wireless battery recharging. Harilaos G. Sandalidis et al. studied the threefold role (illumination, data transmission, and EH) of VLC systems by adapting some EH receiver architectures (single-input single-output, M-pulse amplitude modulation, and dynamic power splitting) recently introduced in RF communication systems. The characteristics of these architectures in terms of trade-off between energy rate and information reception were revealed. Furthermore, the BER performance of pulse amplitude modulated signals with EH was investigated [485]. Thus, EH from a UOC network while using it for data transfer invites immediate research attention with relation to several aspects.
## 2 Materials and Methods
### Preparation of Magnetic Bead + EGCG  
EGCG (Tokyo Chemical Industry, Tokyo, Japan)-modified magnetic beads were synthesized through a two-step process. Initially, EGCG (500 mg) was dissolved in 500 mL of deionized water (DW) and sonicated for 10 min to ensure complete dispersion. Subsequently, T-Fe\({}_{3}\)O\({}_{4}\) magnetic nanoparticles (500 mg) were added to the EGCG solution, which was further sonicated for 10 min to achieve uniform dispersion. The mixture was continuously stirred at room temperature at 1500 rpm for 1 h to facilitate the surface modification of the magnetic nanoparticles with EGCG. After the reaction, the EGCG-modified magnetic beads were separated using a magnetic field and centrifuged at 5000 rpm for 5 min. The supernatant was carefully removed while maintaining the magnetic field. The precipitated beads were washed three times with 400 mL of DW to remove unbound EGCG. Each washing step consisted of sonication for 10 min followed by magnetic separation and centrifugation at 5000 rpm for 5 min. Finally, the purified EGCG@T core beads were thinly spread on a tray and dried in a vacuum oven at 60 \({}^{\circ}\)C until completely dry. The synthesized magnetic beads and EGCG complex were analyzed using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), a Zetasizer, Fourier-transform infrared spectroscopy (FT-IR), and Thermogravimetry Differential Thermal Analysis (TG-DTA).
# Authentication-Based Secure Data Dissemination Protocol and Framework for 5G-Enabled VANET
## 4 System Model for A-MAC
### Initiation Level  
In the A-MAC authentication protocol, each node (we address vehicle and node intermittently) in the region of TA is uniquely identified with an ID. TA generates specific privacy key using security single hash function \(h(.)\) as given in the equation below  
\[\theta_{TA}=h(ID_{TA}\parallel R_{TA}) \tag{1}\]  
where \(\theta_{TA}\) is the privacy key to TA and \(ID_{TA}\) corresponds to the ID of TA. \(R_{TA}\) is the random number generated through the TA. It requires inputting a message of random length and the output message is 128-bit process. MD5 [40] is used to allocate the input message hooked on blocks by 512-bits. Each block is divided into 16 sub-blocks along with 32-bits. In the sequence of processing, the output obtained is four groups of 32-bits each. The four groups are cascaded and hash values through 128-bits are created. Nevertheless, the performance time of MD5 algorithm is better in all respects and execution time is 6 \(\upmu\)s.
## 2 Background  
### Using a CMOS Sensor in VLC  
#### 2.1.1 Rolling Shutter Mechanism  
For a Charge Coupled Device (CCD) sensor, the whole sensor is exposed simultaneously, and the data of all pixels are recorded simultaneously. This mechanism is called the global shutter mechanism of CCD sensors which is illustrated in Figure 1a. On the other hand, for a CMOS sensor, each row in the CMOS sensor is activated sequentially, which means that the data readout and exposure are performed row by row. When the exposure of the row is over, the read out for a row of data is given immediately. Finally, all scanlines captured at different times are combined to form images. This is the mechanism of the CMOS sensor we learned of from Refs. [18; 19; 20], which is called the rolling shutter mechanism. The rolling shutter mechanism of CMOS sensors is illustrated in Figure 1b. The rolling shutter mechanism of the CMOS sensor, which opens and closes during exposure to LED light, will lead to CMOS image sensor captures on the bright stripes and dark stripes.
# Axial Compression Behavior of Steel Angle-Corrugated Steel Plate-Confined Concrete Columns
## 3 Experimental Results and Discussion
### Ductility Index of Specimens  
The ductility index (\(\mu\)) can reflect the deformation properties of the specimens, whose calculation method is the ratio of \(\Delta_{\text{u-0.85}}\) to \(\Delta_{\text{y}}\), as shown in Equation (6):  
\[\mu=\Delta_{\text{u-0.85}}/\Delta_{\text{y}} \tag{6}\]  
where \(\Delta_{\text{u-0.85}}\) is the displacement corresponding to the load dropping to 85% peak load (\(0.85N_{\text{u}}\)); \(\Delta_{\text{y}}\) is the displacement corresponding to the yield load, which is determined by the equivalent elastic-plastic energy method [28]. In the equivalent elastic-plastic energy method, the original curve is replaced with an ideal elastic-plastic line with the same envelope area and concerning the displacement of the inflection point of the line as the yield point. Figure 9 shows the method of determining \(\Delta_{\text{u-0.85}}\) and \(\Delta_{\text{y}}\).  
Figure 10 plots the ductility index \(\mu\) of the different specimens. Compared with the SA-CS-230 column, the \(\mu\) of the CFST-1 column decreased by 22.36%, while the \(\mu\) of the CFST-2 column decreased by 16.67%. Combined with the results of \(I_{\text{s}}\), it can be inferred that the mechanical properties of the SA-CS column are better than those of the CFST column. In addition, for the SA-CS columns, the ductility index presented a downward trend with the increase in the section size, which might have occurred because as the section size of the specimen increases, the transverse stress of the corrugated steel plate increases. The corrugated steel plates would yield earlier, which leads to the specimen presenting a steeper slope in the descending stage, resulting in a decrease in \(\Delta_{\text{u-0.85}}\).  
Figure 10: Ductility index of specimens.  
Figure 9: Equivalent elastic-plastic energy method.  
However, like \(I_{s}\), the \(\mu\) also decreased slightly with the decline of the steel ratio. The phenomenon indicated that the mechanical properties of the SA-CS column are slightly affected by the steel ratio. This phenomenon can be considered to reduce the steel ratio appropriately for the new type of composite column in the project.
## 4 Origin-Destination Matrices Estimation
### Numerical Results  
After the cleansing process, 311,772 records were discarded from the dataset corresponding to May 2015, leading to a cleansed dataset comprised of 20,048,063 records. For the destination estimation process, this dataset was split into chunks, where each chunk held the information for an entire day starting and ending at 3:00. Additionally, since the destination estimation algorithm requires at least two transactions to perform trip-chaining, the records associated to cardholders that only performed one transaction within a given day were filtered from the dataset. As a result, the destination estimation algorithm was applied to a set of 18,885,711 records. Out of these records, the implemented algorithm was able to assign a destination to 15,414,230 trips, achieving a success rate of 81.62%. This is a highly competitive result, considering the success rates achieved by other works in the related literature, e.g., 57% [13], 66% [12], 80% [14]. Each identified trip holds the following information: boarding bus stop, time stamp at boarding, bus line identifier, and alighting bus stop.  
Computed results allowed identifying 9,485,904 OD pairs. At the finest grain, OD matrices were generated considering each pair of bus stops (size 4718 \(\times\) 4718). At a more coarse grain, OD matrices were built at the census tract level (size 1063 \(\times\) 1063). Both OD matrices are available at www.fing.edu.uy/~renzom/msc in CSV files with their corresponding metadata. For the sake of visualization, OD matrices in this article are aggregated by municipality (size 8 \(\times\) 8). Table 2 outlines the estimated OD matrix corresponding to the studied dataset (each municipality is represented by its identifying code).  
The largest values are located in the diagonal of the computed OD matrix, which represent trips starting and ending within the same municipality. Municipality B stands out as both the largest generator and attractor of trips when considering the total number of OD pairs. This is consistent with the fact that the city center and other surrounding areas are within municipality B, where multiple workplaces, public offices, and services are located. Considering that most trips correspond to people commuting to their workplaces (30.9% according to the 2016 mobility survey), these observations could suggest that the majority of citizens work either within their own municipalities or travel to municipality B where most job opportunities are located. The lowest number of transactions occur in municipalities F and G, which have large rural areas with lower population density.
## 1 Introduction
### Review Assessment
#### 1.3.2 Limitations  
* This review considered articles from selected databases, including Elsevier, IEEE, and MDPI, which are mostly indexed in Scopus. However, Scopus itself was not directly searched, which may have limited access to additional journals, such as those from Springer.
* The model comparison primarily focuses on accuracy, as not all of the included literature reported the same evaluation metrics, making direct comparisons difficult.
* The included literature reveals a limitation in the detailed analysis of deep learning model architectures for asthma classification using imaging data, since the primary focus was on structured medical data.  
\begin{table}
\begin{tabular}{c c} \hline
**Score** & **Description** \\ \hline
1 & Miscellaneous diseases analyzed using ML or DL techniques \\
2 & Pediatric asthma analyzed with ML or DL models \\
3 & Environmental or respiratory data with ML or DL techniques \\
4 & Adult asthma with environmental or EHR data and ML or DL algorithms \\
5 & Adult asthma with combination of environmental and EHR data using ML or DL methods \\ \hline \end{tabular}
\end{table}
Table 1: Scoring table depicting the scale and description assigned to each article.  
Figure 3: The methodology adopted in this review involved analyzing three research databases, beginning with preliminary screening and concluding with specific criteria for final selection.  
* The review does not extensively cover synthetic data generation or augmentation techniques, such as the Synthetic Minority Oversampling Technique, as these methods require a separate in-depth discussion.
## 2 Vehicular Visible Light Communication Issues, Related Work, and Specificity of this Work
### State of the Art Summary and the Position of this Work with Respect to Other Works  
Although important progress has been achieved, there are limited experimental demonstrations that show a VLC system that is able to fully comply with the requirement of the automotive area. Thus, most existing systems can have remarkable performances, as they focus on a specific challenge. However, there is limited work focused on a holistic approach that leads to a VLC system that is capable of providing mobility, long-range, high data rates and resilience to optical noise sources and extreme weather phenomena. Thus, significant work in this area is still required. In this context, this work aims to provide a VLC system that is designed based on a holistic approach that focuses on the overall system performances. The proposed prototype is designed to work in variable scenarios, distances, under different optical noise exposure levels, in unfriendly meteorological conditions, and so on. Thus, unlike many of the existing VLC prototypes, this one is not tested only in ideal conditions or in circumstances that emphasize a specific ability (i.e., noise resilience, data rate, communication range), but it is also evaluated in a multitude of situations, favorable and unfavorable. Accordingly, when compared to the VLC systems and solutions that are focused on noise mitigation, the one that is presented in this work aims to provide similar resilience to optical noise sources (i.e., up to few thousands of lux), while being able to provide a superior communication range than [21; 23], better mobility than [33], and a simpler design than [54; 55; 56; 57]. When compared to the vehicular VLC systems that address tens of meters communication ranges, the proposed prototype aims to provide higher resilience to noise than [16; 21; 30; 58; 59], wider FOV and better mobility than [16; 58; 59], and lower complexity than [60]. On the downside, the proposed VLC prototype achieves significantly lower data rates than [59; 61; 62; 63; 64; 65; 66; 67], but it provides better resilience to noise and longer communication ranges ([64] provides a rather similar communication range). Thus, high-speed camera systems that are based VLC systems can achieve data rates up to few tens of Mb/s data rates [61; 62; 63], whereas some of the short-range (i.e., 1-3 m) photodiode-based vehicular VLC systems can provide hundreds of Mb/s data rates [65; 66; 67; 60]. Additionally, as compared to most of the upper-mentioned VLC systems, this one is tested in a wider range of scenarios (i.e., indoor and outdoor, short range to long range, different optical noise intensities, unfriendly weather conditions) in order to demonstrate the benefits of a holistic approach in vehicular VLC design.
# Exploiting Lunar Navigation Constellation for GNC Enhancement in Landing Missions
## 2 Simulation Environment
### User Navigation Equipment  
Dealing with a navigation filter, it is fundamental to correctly analyse the measurements that are exploited by the estimation algorithm in order to simulate the behaviour of the sensors providing such observations and define the measurement functions used within the filter itself.
# Research on Real-Time Control Strategy for HVAC Systems in University Libraries
## 2 Materials and Methods
### Energy-Saving Strategies  
The energy-saving strategy design is based on the intelligent on-demand regulation of the central HVAC system equipment according to the cooling demand of the HVAC area of the building, as well as the real-time online optimization of each state point of the system operation according to the meteorological parameters and real-time operation data of the system.  
1.1 Optimization of Chilled Water Supply and Return Trunk Differential Pressure Setting Based on Weather Change  
By collecting data on system operations and changes in terminal load, we can optimize the pressure differential between the chilled water supply and return pipes. This adjustment enables us to achieve energy savings in the operation of the chilled water pumps.  
For the secondary pump system, a bypass pipe must be set between the primary and secondary systems to balance the flow between the primary and secondary pumps. However, in the actual operation of the system, the secondary system water flow rate  
Figure 1: Structure of the study.  
changes with the load. When the load is low, the secondary system water flow rate is small, and because the primary system has a fixed flow rate, the positive flow rate of the bypass pipe is large, resulting in a waste of energy in the primary system. Therefore, for the secondary system, a primary system using a variable-flow design can effectively reduce the operating energy consumption of the system (Figure 2).  
For the primary variable-flow system, fixing the differential pressure between the primary system water supply main pipe and the return main pipe can effectively reduce the energy consumption of the primary system; however, when the number of hosts changes, the initially set target value of differential pressure will no longer be applicable. Therefore, it is necessary to optimize the set value of differential pressure according to the temperature difference between the supply and return water of the primary circuit and the current host loading rate; that is, when the temperature difference value is lower and the host loading rate is higher, the differential pressure set value needs to be reduced appropriately in accordance with a certain rule. In other cases, the differential pressure setting value can remain unchanged. Figure 3 shows a structural diagram of the system at the end of the refrigeration unit. Figure 4 presents a basic step diagram of the proposed strategy.
# QoS-Aware Scheduling Algorithm Enabling Video Services in LTE Networks
## 5 Result and Discussion
### Video Delay  
Figure 4 depicts video stream packet delay outcomes on the LTE network with increasing user load. The proposed technique provides less delay than other techniques because resource packet provisioning for video applications has the least PLR, as depicted in Figure 2. EXPRule, EXP-PF, MLWDF provide lower delay than PF. The PF technique supports non-real-time flow by providing fairness among users. When many resources blocks are provided video service traffic, the EXP-PF and EXP-Rule algorithms have relatively shorter delays than MLWDF, with 0.01723 and 0.01566 achieved for EXP-PF and EXP-Rule, respectively, at 20 users. PrOEXPRule achieved 0.00415 at 20 users for packet delay; PrOEXPRule relies on exponential expressions and takes into account the HOL delay and delay priority, so it provides better results for delay compared to other algorithms.
## 3 Results
### NDVI, EVI, and SIF Simulation and Prediction  
Figure 10 displays the comparison results of the simulated predictions for the NDVI, EVI, and SIF for 2015 and 2018 (A, B, and C are the original images, and A1, B2, and C3 are the predicted images). Based on the regional NDVI, EVI, and SIF data in 2005 and 2010, the probability transfer matrix for each type of NDVI, EVI, and SIF from 2005 to 2010 was obtained under the IDRISI platform, and the CA-Markov model was applied to generate the suitability profiles to obtain the simulated data in 2015 and 2018. The decomposition results of the NDVI, EVI, and SIF for 2015 and 2018 were compared with the simulation results, and the simulation results were verified using kappa coefficients. The predicted kappa coefficient values of the NDVI, EVI, and SIF for 2015 were 0.8631, 0.8864, and 0.9041, and for 2018 were 0.848, 0.8516, and 0.8928, respectively (generally, when the kappa coefficient is greater than or equal to 0.75, the simulation prediction accuracy is considered high [20], and thus, the simulation of the NDVI, EVI, and SIF changes passed the accuracy test).  
Figure 11 presents the simulation projection results of the NDVI, EVI, and SIF for 2020-2025. The future vegetation in China still offers a better form overall, especially in the southeast region where the vegetation improvement trend is significant. However, it still needs to be improved in some areas such as the northwest, where it is necessary to strengthen the ecological environment construction. By combining the results from Tables 4-6, it can be seen that the NDVI, EVI, and SIF lower types decreased by 0.3%, 0.2%, and 0.5%. Still, the NDVI lower types increased by 0.4% in 2022, which occurred mainly in the northwest region and can be attributed to the more severe natural environment in 2022 in the northwest region. Common types differ significantly, with the EVI and SIF higher types increasing by 1.9% and 1.3%, the low types decreasing by 1.4% and 0.5%, and the NDVI remaining essentially unchanged. The response of the NDVI to vegetation could have been better and fluctuated insignificantly when NDVI values were lower and higher. Although the EVI was an improved version of the NDVI, its effect was still insignificant at lower EVI values. In contrast, the variation in the SIF is still very significant at its lower and higher values, which confirms from a new perspective that the response effect of the SIF on vegetation is higher than that of the traditional NDVI and EVI.  
Figure 10: _Cont._Figure 11: _Cont._  
Figure 10: The graph at the top shows the forecast results for NDVI, EVI, and SIF in 2015, while the chart at the bottom shows the forecast results for the same indices in 2018. **(A)**: Original NDVI images in 2015 and 2018; **(B)**: Original EVI images in 2015 and 2018; **(C)**: Original SIF images in 2015 and 2018; **(A1)**: Predicted NDVI images in 2015 and 2018; **(B1)**: Predicted EVI images in 2015 and 2018; **(C1)**: Predicted SIF images in 2015 and 2018.  
Figure 11: Spatial distribution of NDVI, EVI, and SIF forecast results in 2020–2025.
# Multilabel Classification of Radiology Image Concepts Using Deep Learning
## 3 Experiments and Results  
### Dataset Exploration  
Figure 5 shows the distribution of concepts in the ImageCLEF dataset, the top 10 most frequent concepts.  
The most frequent categories are \"Tomography, Emission-Computed\" (29%) corresponding to nuclear medicine imaging techniques such as PET and SPECT, and \"X-Ray Computed Tomography\" (29%), followed closely by \"Diagnostic Radiologic Examination\" (27%). These three categories dominate the dataset, indicating a strong prevalence of cross-sectional imaging techniques (CT and general diagnostic radiology). Other significant concepts include \"Magnetic Resonance Imaging\" (17%) and \"Ultrasonography\" (12%), confirming the relevance of MRI and ultrasound imaging within the dataset. Less frequent categories, such as \"Angiogram\" (7%), \"Heart Atrium\" (2%), \"Intestines\" (2%), \"Mediastinum\" (2%), and \"Both Kidneys\" (2%), represent more specific anatomical or procedural concepts.  
Figure 5: Distribution of CUIs in the dataset.  
This distribution highlights the imbalance present in the dataset, with a few dominant concepts and many rare ones, which needs to be addressed carefully in the model training and evaluation phases.