esa-sceva/satcom-chunk-collection huggingface dataset:
## 4 Integrity Monitoring
### FDE Procedure
The SST passes, when  
\[|o_{q}^{T}\big{(}\Delta\bar{r}_{0}-\Delta\bar{r}_{k}\big{)}|\leq T_{k,q} \tag{43}\]  
for \(q=1\), \(2\) and \(3\). For all the subset solutions that cannot pass the SST, the subset delivering the largest value of \(|o_{q}^{T}(\Delta\bar{r}_{0}-\Delta\bar{r}_{k})|/T_{k,q}\) (for \(q=1\), \(2\) or \(3\)) is determined, and the corresponding observations \(k\) are excluded. The SST is re-computed until all subsets passing the test is identified. After the SST, a confirmation test in the observation domain is performed using the \(\chi^{2}\)-test. The test passes, when  
\[y_{x}\big{(}Q_{y}^{-1}-Q_{y}^{-1}A_{x}(A_{x}^{T}Q_{y}^{-1}A_{x})^{-1}A_{x}^{T }Q_{y}^{-1}\big{)}y_{x}^{T}\leq Q_{\chi^{2}_{j}}^{-1}(1-P_{FA,\chi^{2}}) \tag{44}\]  
Recall that the probability of false alert allocated to the \(\chi^{2}\)-test is set to \(10^{-6}\) in this study. In case that the \(\chi^{2}\)-test does not pass but the SST passes, the protection levels computed in the next subsection are not considered valid.
## 2 Methodology
### Identifying Websites for Information Extraction  
In order to reach safe conclusions regarding the evolution of media outlet websites through time, a large number of websites must be used, as well as multiple instances of each such website over the course of time. A large data set can lead to reliable results and create an impression that accurately represents reality. For that purpose, the archival Web service that was selected as the main provider of data concerning these websites was the Wayback Machine Internet Archive. As seen in the work of [PERSON] et al. [PERSON] et al. (2015), most Web archiving initiatives are national or regional. Out of the few international ones, the Internet Archive is both the largest and the oldest, dating back to 1996. It boasts over 625 million Web pages ([PERSON] et al., 2015) which it provides to interested parties through its Wayback Machine. Using the Wayback Machine was considered the best way to collect a variety of instances for each studied website, which spanned over a representative period of time.  
Another consideration, besides the number of instances, was which specific websites were to be targeted. A reliable metric of a media outlet's impact and visibility is its popularity based on digital traffic. Additionally, this popularity can ensure the existence of multiple instances of archived website data in Web archives. Based on that, a sample of the 1000 most popular websites was obtained from the SimilarWeb digital intelligence provider in the category of \"News & Media Publishers\" in Greece. SimilarWeb is a private company aiming to provide a comprehensive and detailed view of the digital world ([PERSON] et al., 2015). Information about a website's online market share, its global rank, and more were collected manually in the form of text files and using an algorithm scripted with PHP, this information was parsed and imported into a relational database powered by the MariaDB database management engine. This process is visually presented in Figure 1.  
Both international websites with a popular presence in Greece and popular Greek media outlets were included in the final list of websites to be investigated. Overall, the websites presented a varied mix including popular international online media outlets  
Figure 1: Visual representation of the process of website information collection.  
(e.g., Yahoo, MSN, BBC, the NYTimes, etc.), popular Greek online media outlets such as (e.g., protothema.gr, ifimerida.gr, newsbomb.gr, etc.), a series of local news outlets with a popular online presence (e.g., typosthes.gr, thebest.gr, larissanet.gr, etc.), and more.
## 5 Particle Detectors
### Mass Spectrometry  
Mass spectrometry (MS) is a set of analytical techniques used to discriminate charged particles, based on their different mass-to-charge ratios, which result in different trajectories in EM fields [247]. It is possible to discriminate different masses and measure relative concentrations of isotopes, atoms, or molecules, so, as a whole, mass spectrometers can be considered as versatile and highly sensitive detectors. A mass spectrometer is basically composed of three main modules:  
* An ion source (e.g., inductively coupled plasma source, thermal ionization source, glow discharge source, CS sputter source) to produce ions from the sample to be analyzed,
* A mass analyzer (e.g., quadrupole mass filter, magnetic sector field, a combination of magnetic and electrostatic sector fields) to separate ions of different types, and
* A detector (e.g., electron multipliers in general used for single collector instruments, or Faraday cups/combination of electron multipliers and Faraday cups for multi-collector devices) for the transmitted ions.  
Mass spectrometry is widely used in several fields of science and technology. In particular, the elemental fingerprinting and the isotopic composition of archaeological materials and artifacts offer scientists information about the origin, provenance, use, chronology, authenticity, and manufacture [248; 249; 250; 251; 252; 253]. MS analytical techniques are destructive, since the sample needs to be converted in the most appropriate chemical form for the analysis, and for this reason are bulk analytical methods. However, only a very small amount of sample, typically from a few to a few hundred mg, is required, and thus, in many cases, destructivity is not a real obstacle for the application of MS techniques in CH.  
Within INFN-CHNet, the mass spectrometric techniques used are high-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for elemental analysis at trace level, and thermal ionization mass spectrometry (TIMS) and stable isotope ratio mass spectrometry (IRMS) for the determination of isotope ratios of heavy (Sr, Pb, Nd,... ) and light (C, N, O, S) elements, respectively. A surface analysis mass spectrometric technique, time of flight-secondary ion mass spectrometry (ToF-SIMS), is also available, enabling the detection of all organic and inorganic species, with their relative isotopes, in the mass range from 1 to 10,000 AMU. In addition, a particle accelerator is routinely used for accelerator mass spectrometry (AMS), which enables measuring rare isotopes in ultra-low concentrations and is mainly used for \({}^{14}\)C dating.
## 4 Discussion
### Practical Applications  
The purpose of this research was to provide a set of guidelines regarding spatiotemporal variables (possession duration, number of passes used, starting and finishing court zone) and technical-tactical variables (type of offense and type of ending action), with the aim of improving the understanding of these actions in critical moments of the game and enhancing the design of specific training sessions. Coaches can utilize the findings on the effectiveness of certain patterns in high-pressure situations (last minutes and overtime) to design drills that meet the demands of the competition.  
On one hand, training these situations through short possessions (less than 17 s) can help players improve decision making and execute fast offenses, even through fastbreaks, maximizing the likelihood of success under pressure. Additionally, strategies can be developed based on the score, where teams that are losing in critical moments opt for faster plays with fewer passes, while teams that are winning use longer possessions to control the pace of the game. Coaches can practice these situational approaches, teaching players to adjust the speed and type of offense depending on the score and the remaining time, training both result-containment tactics and score-recovery tactics.  
Similarly, strategies can be developed where winning teams aim to place the ball in the hands of players with high free throw percentages, as the opposing team will likely commit personal fouls, resulting in free throws. On the other hand, teams that are losing should finish plays with two- or three-point shots.  
Furthermore, individual decision making in high-pressure contexts can be encouraged. Coaches can work on improving individual skills under pressure, in terms of both technical execution and decision making, preparing players to execute effective plays without relying on complex team systems. Finally, the data indicate that completing plays in certain areas of the court (such as near the basket or in the right-side zones) increases the chances of success. Coaches can plan drills that strengthen offensive actions in these areas, teaching players to identify and capitalize on opportunities in the most effective spots.
## 3 Overview of Wavelet Transform and Diversity Combining
### Overview of Diversity Combining  
A combining technique is popular to combat the effects of distortion, referred to as fading, on wireless systems [18]. When there are a transmitter and multiple receiving antennas, the received signals have different degradation since they experience different fading levels.  
The receiver combines diverse signals bearing the same information in order to increase the overall quality of the received signal [18]. There are four types of diversity combining: maximal-ratio combining, equal-gain combining, selection combining, and switch combining. Maximal-ratio combining sums the received signal with weights. Equal-gain combining sums all the received signals synchronously. Selection combining selects the best signal among the multiple received signals. Switch combining switches to another signal when the quality of the selected signal goes below a certain threshold.  
In this study, there is only one source (heart) and diverse signals (multiple signals measured at different locations). Hence, a diversity combining scheme is employed to improve the received signal quality. While the signal-to-noise ratio is used as a quality measure in the communication community [18], a signal and noise cannot be separately measured in an SDPPG (or PPG) signal. Hence, for diversity combining, a quality measure for SDPPG signals will be defined and explained later.
# Study of Innovative Connector for Steel-Concrete Composite Structures
## 5 Conclusions  
1. Based on the experimental tests, it was found that the proposed solution of fasteners made of corrugated sheet and shot nails can be used as the connector for steel-concrete composite floor beams.
2. Each type of analyzed fasteners was found to be ductile based on the criterion presented in Eurocode 4 standard.
3. The sheet thickness and the number of nails determine the load capacity of the fasteners. The load-bearing capacity of the fastener can be adjusted by changing the corrugated sheet thickness and changing the number of nails shot in the single fold of the sheet.
4. The breaking load of the connector made of 1.00 mm thick corrugated sheet and 4 pcs. of shot nails is 47.50 kN. The connector made of 1.00 mm thick sheet and two pieces of nails is characterized by breaking load of 30.83 kN. The breaking load of the connector made of 1.25 mm thick sheet and two pieces of nails is 34.17 kN.
* It is planned that experimental tests of the steel-concrete composite beam will be carried out with the use of tested connectors made of corrugated sheet in the shape of a dovetail and shot nails. At the same time, it is planned to make a parameterized numerical model that would allow one to optimize the steel-concrete composite beam, especially the geometry of the sheet as well as the number and spacing of the nails.  
Conceptualization, P.K.; methodology, A.D. and P.L.; formal analysis, A.D.; investigation, A.D. and P.K.; resources, P.K.; data curation, P.K.; writing--original draft preparation, A.D., P.L. and P.K.; writing--review and editing, S.G.; visualization, A.D.; supervision, P.K.; project administration, A.D.; funding acquisition, P.K. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
The raw data supporting the conclusions of this article will be made available by the authors on request.  
The authors declare no conflicts of interest.
## 1 Introduction
While some studies suggested a different hardware configuration, such as an EEG cap lead reconfiguration, a specific cap-cable configuration, etc., [8; 15; 19] for GA reduction, according to the recent literature, no study has investigated the effect of a phantom shape when characterizing the GA in EEG data, which is done in this work. In this study, EEG data were acquired three times using the same experimental setup with a spherical phantom, a head-shaped phantom, and six healthy volunteers. The primary contribution of this work is the investigation of how the shape of the phantom affects the magnitude of the GA generated by each of the three orthogonal gradients (anterior-posterior (AP), right-left (RL), and foot-head (FH)). Secondly, we discuss our findings obtained from the different experimental setups. Finally, we use the quantitative measurement of the EEG data recorded using a standard echo-planar imaging (EPI) sequence to confirm the findings of this study. This paper is organized into five sections. A discussion about phantom production is given in Section 2; a detailed discussion of the experimental setup, hardware configuration, study design, and data acquisition is given in Section 3; Section 4 presents the details of the analysis applied for data processing; experimental findings, performance measures, experimental evaluations, and possible impacts are discussed in Section 5; finally, the paper's conclusions are presented in Section 6.
# Study on Thermal Radiation Characteristics and the Multi-Point Source Model of Hydrogen Jet Fire
## 4 Results and Discussion  
### Model Validation  
Water vapor is the main product of hydrogen combustion. Figure 5 shows the contour plots of the temperature, OH radical, and water vapor mass fraction distributions for the hydrogen jet fire under the validation conditions. In Figure 5, it can be observed that the distribution range of water vapor largely coincides with the high-temperature region, and the flame temperature peak appears at the same flame height as the highest OH concentration. This is because OH is a crucial radical in the reaction of H\({}_{2}\) and air, participating in major stepwise exothermic reactions, which results in higher temperatures in this flame region. The rapid increase and decrease in the OH concentration along the flame direction indicate that OH is quickly generated and consumed. The distribution of the OH radicals reveals the jet region that is primarily involved in the combustion reaction.  
To verify the accuracy of the numerical simulation model, the present simulation results were compared with the experimental results of [PERSON] et al. (2018) under the same conditions. The flame length is a critical parameter in studying large-scale jet fires, and this study adopted the flame length as the validation parameter. The flame length derived through simulation was determined using two methods. The first method was the temperature threshold, which was proposed by [PERSON] et al. (2018), who used a flame temperature of 1300-1500 K as the criterion for the flame length, and this study set the temperature threshold at 1500 K. Moreover, the OH concentration is usually used to determine the main reaction region of hydrogen combustion, and the flame length is determined by selecting 5% of the maximum OH concentration as the OH threshold. By extracting the flame temperature and OH concentration distribution of the jet fire, the flame lengths calculated by the two methods were 6.5 m and 6.9 m, respectively, as shown in Figure 6. The experimental flame length obtained by [PERSON] et al. under the same conditions was 6.7 m, indicating a small discrepancy between the simulated and experimental flame lengths, demonstrating the reliability of the simulation method.  
Figure 5: Temperature and product distributions in _xy_-plane.  
Figure 6: Temperature and OH concentration in _y_-direction of hydrogen jet fire.
## 4 Results and Analysis
### Cross-Validation  
The cross-validation of this paper selected the FPAR products of MODIS, GEOV1, and GLASS (referred to as MODIS-FPAR, GEOV1-FPAR, and GLASS-FPAR), as well as FY-FPAR, to verify the accuracy of the same spatial range at the same time and to analyze the spatial consistency, time consistency, and relevance.
## 3 Results and Discussions
### Optimum Mixing Ratio  
#### 3.2.1 Water-to-Binder Ratio  
The water-to-binder (W/B) ratio influences the workability, strength, and durability of SRC, and it should be optimized [25]. The variations in the compressive strength of SRC were investigated for different W/B ratios and curing periods (Figure 3). The SRC showed compressive strength meeting the disposal criterion (3.44 MPa) when the W/B ratios were 0.3 and 0.4 after 28 days of curing. In the cases of 0.5 and 0.6 W/B ratios, the compressive strengths of SRC were measured to be 3.1 and 2.8 MPa, respectively, after the same period of curing, and they did not satisfy the disposal standard. Compared with OPC, CWP contained an insufficient quantity of substances, such as \(\beta\)-C\({}_{2}\)S, which could provoke the hydration reaction. Therefore, the compressive strength of the SRC was weakened with W/B ratios greater than 0.5 because the water was likely to exceed the quantity needed for  
\begin{table}
\begin{tabular}{c c c c c c c c c c} \hline  & **SiO\({}_{2}\)** & **CaO** & **Al\({}_{2}\)O\({}_{3}\)** & **Fe\({}_{2}\)O\({}_{3}\)** & **K\({}_{2}\)O** & **Na\({}_{2}\)O\({}_{3}\)** & **MgO** & **SO\({}_{3}\)** & **Others** & **LOI** \\ \hline Concrete & & & & & & & & & & \\ waste & 44.5 & 18.8 & 8.73 & 3.36 & 1.9 & 1.82 & 1.66 & 0.99 & 1.07 & 17.16 \\ (\(<\)0.38 \(\mu\)m) & & & & & & & & & & \\ GGBFS & 32 & 36.8 & 13.7 & 0.55 & - & 0.53 & 3.39 & 1.25 & 2.24 & 9.54 \\ \hline \end{tabular}
\end{table}
Table 6: The XRF results on the chemical compositions of the CWP and GGBFS (unit: weight %).
# Energy Efficient Access Point Placement for Distributed Massive MIMO
## 2 System Model and Problem Formulation
### Signal Power at Each Potential User Location  
As mentioned earlier, the decision on the AP placement happens at a strategic level. It involves a lot of uncertainty. Therefore, the impact of imperfect channel state information is not considered. To simplify the calculation of the average received signal power, we assume the availability of perfect channel state information and maximum ratio precoding, thereby ensuring that the signals from the APs coherently combine at user locations. When simultaneously sending signals from distributed APs, the received signal \(y_{i}\) at location \(i\) is calculated as  
\[y_{i}=\sum_{l\in\mathcal{L}}x_{l}\sum_{m=1}^{M}h_{ilm}w_{ilm}^{*}s+n_{i}, \tag{1}\]  
where the binary variable \(x_{l}\) equals one if an AP is deployed at a location \(l\) and zero otherwise. We denote the channel response between a user location \(i\) and an antenna  
Figure 4: (**a**) shows the eight possible broadside directions for the array when mounting an AP on a wall. (**b**) is an example of the broadside directions for different potential AP locations. The dark gray area represents a building. The black dots next to the building are the potential AP locations. The blue arrows indicate the broadside directions for each potential AP location.  
Figure 3: Elevation plane gain patterns (dBi) of the considered isotropic element and patch element. (**a**) Isotropic antenna; (**b**) Patch antenna.  
element \(m\) in the array of AP \(l\) as \(h_{ilm}\). The information signal \(s\) is precoded by applying the precoding weight  
\[w_{ilm}=\frac{h_{ilm}}{\sqrt{\sum_{l\in\mathcal{L}}x_{l}\sum_{m=1}^{M}|h_{ilm}|^{ 2}}}, \tag{2}\]  
which determines the spatial directivity of the transmission. The additive white Gaussian noise \(n_{i}\) has zero mean and variance \(\sigma^{2}\).  
The transmit power in the information signal \(\mathbb{E}\{|s|^{2}\}\) equals the total transmit power in the system \(Tp_{\mathbb{T}}\). The average received signal power \(\widetilde{p}_{\mathbb{R}_{i}}\) at a user location \(i\) is defined as  
\[\widetilde{p}_{\mathbb{R}_{i}}=\mathbb{E}\Big{\{}|s|^{2}\Big{\}}\mathbb{E} \Bigg{\{}\Bigg{(}\sum_{l\in\mathcal{L}}x_{l}\sum_{m=1}^{M}h_{ilm}w_{ilm}^{*} \Bigg{)}^{2}\Bigg{\}}=Tp_{\mathbb{T}}\sum_{l\in\mathcal{L}}x_{l}\sum_{m=1}^{M }|h_{ilm}|^{2}. \tag{3}\]  
We denote the average channel gain between an AP \(l\) and a location \(i\) by \(\widetilde{\beta}_{il}\) and compute it as  
\[\widetilde{\beta}_{il}=\mathbb{E}\Bigg{\{}\sum_{m=1}^{M}|h_{ilm}|^{2}\Bigg{\}}. \tag{4}\]  
The average received signal power can then be expressed as  
\[\widetilde{p}_{\mathbb{R}_{i}}=Tp_{\mathbb{T}}\sum_{l\in\mathcal{L}} \widetilde{\beta}_{il}x_{l}. \tag{5}\]  
Different ways of modeling \(\widetilde{\beta}_{il}\) are discussed in Section 3.
## 2 Theoretical Framework
### Technological Acceptance Model  
The original proposal for the TAM [32] is made up of five concepts: perceived usefulness, perceived ease of use, attitude toward using, behavioral intention to use, and actual use. Following [PERSON] proposal, the relationships between these constructs are illustrated in Figure 1. In fact, the defined model in this study is inspired by this framework whilst adopting a TAM2 and TAM3 perspective. This implies that it is assumed the incorporation of their three key constructs [50; 51]; perceived usefulness (PU), perceived ease of use (PEU) and behavioral intention to use (BI), so that the two belief constructs (PU and PEU) are primary determinants of an individual's BI to use an ICT [52]. The TAM literature considers the removal of the construct attitude towards use to be viable, owing to its reduced mediating effect on BI [39].  
TAM3, which includes TAM2, was proposed initially as a means of understanding employee use of ICT in a business environment [51]. It emphasizes individual and social factors that influence the individual-level adoption behavior of an ICT [53]. Hence, the user perception of technology determines its level of acceptance. Specifically, TAM3 [50] takes the variables from TAM2 that influence PU (voluntariness, experience, subjective norms, job relevance, output quality and results in demonst  
Figure 1: Technology Acceptance Model (TAM) original proposal [32].  
that the anchor (computer self-efficacy, perception of external control, computer anxiety and computer playfulness) and adjustment (perceived enjoyment and objective usability) factors impact PEU.  
PU is defined by [32] (p. 320) as \"the degree to which a person believes that using a particular system would enhance his or her job performance\", and PEU is \"the degree to which a person believes that using a particular system would be free of effort\". Based on the TAM postulates, PEU and PU are factors that influence BI [50], and the impact is assumed to be positive. Hence, in this present study, the greater the students' PEU and PU regarding OSS, the more likely the students' BI. Thereby, the following hypotheses were included in the TAM3 model (Figure 2):  
**Hypothesis 1 (H1).**: _Perceived ease of use (PEU) has a positive effect on the perceived usefulness (PU) of OSS._  
**Hypothesis 2 (H2).**: _Perceived ease of use (PEU) has a positive effect on behavioral intention to use (BI) OSS._  
**Hypothesis 3 (H3).**: _Perceived usefulness (PU) has a positive effect on behavioral intention to use (BI) OSS._