esa-sceva/satcom-chunk-collection huggingface dataset:
Sensors_**2014**, _14_, 24408-24424; doi:10.3390/s141224408  
_Sensors_  
ISSN 1424-8220  
www.mdpi.com/journal/sensors  
_Article_  
A Smart City Application: A Fully Controlled Street Lighting Isle Based on Raspberry-Pi Card, a ZigBee Sensor Network and WiMAX  
**[PERSON] *, [PERSON] and [PERSON]**  
Dipartimento di Scienze, Universita degli Studi \"Roma Tre\", Via della Vasca Navale 84, Rome 00146, Italy; E-Mails: [EMAIL_ADDRESS] (M.C.); [EMAIL_ADDRESS] (D.T.)  
* Author to whom correspondence should be addressed; E-Mail: [EMAIL_ADDRESS]; Tel.: +39-06-5733-7347.  
External Editor: [PERSON]  
_Received: 27 October 2014; in revised form: 5 December 2014 / Accepted: 12 December 2014 / Published: 18 December 2014_  
**Abstract:** A smart city application has been realized and tested. It is a fully remote controlled isle of lamp posts based on new technologies. It has been designed and organized in different hierarchical layers, which perform local activities to physically control the lamp posts and transmit information with another for remote control. Locally, each lamp post uses an electronic card for management and a ZigBee tlc network transmits data to a central control unit, which manages the whole isle. The central unit is realized with a Raspberry-Pi control card due to its good computing performance at very low price. Finally, a WiMAX connection was tested and used to remotely control the smart grid, thus overcoming the distance limitations of commercial Wi-Fi networks. The isle has been realized and tested for some months in the field.  
**Keywords:** control systems for smart grids; lighting system; wireless networks for smart grids; ZigBee; sensors; Raspberry-Pi; ARM processor
# An Approach to Designing Critical Railway Voice Communication
## 4 FRMCS Common Functions as RESTful Service Blocks  
Any physical or logical object in REST is represented as a resource that is regarded as a service building block. Each REST resource is uniquely identified and addressable by its Uniform Resource Identifier (URI). Resource manipulation is achieved through its representations (data, metadata, and hypermedia links), which allows for the modification of the resource state. Resource state manipulation is typically based on HTTP GET/POST/PUT/DELETE methods.
# Parallel Accelerated Fifth-Order WENO Scheme-Based Pipeline Transient Flow Solution Model
## 7 Conclusions  
Based on the one-dimensional pipeline non-constant flow equation set, the virtual boundary technique is adopted at the upper and lower ends of the model. The bifurcated pipeline boundary solution method is combined with the Lax-Friedrichs splitting method for flux decomposition, and the time term is discretized by the second-order Runge-Kutta method. Moreover, a fifth-order WENO finite volume scheme water hammer solution model is established for the long-distance water transmission system. The key results are as follows.  
(1) The model is verified to ensure low numerical dissipation and lack of spurious oscillations at tiny Courant numbers under ideal conditions. The model is suitable for large and complex water conveyance systems. Compared to the commonly used MOC, the computation load of the model is 35% to 90% less than the MOC and 15% to 39% less than the second-order Godunov scheme while maintaining the accuracy of the results.  
(2) Using GPU acceleration technology to accelerate the model, the model can achieve a significant acceleration effect while ensuring accuracy when the number of grids is greater than thousands. As the number of meshes increases, the GPU acceleration effect becomes more and more significant. The study found that GPU with 32 threads can deal with engineering problems within hundreds of thousands of grids with the best acceleration effect.  
Conceptualization, T.M. and G.L.; methodology, T.M. and G.L.; software, T.M.; validation, T.M.; formal analysis, G.L.; resources, T.M.; data curation, T.M.; writing--original draft preparation, T.M.; writing--review and editing, G.L.; supervision, G.L.; project administration, G.L.; funding acquisition, G.L. All authors have read and agreed to the published version of the manuscript.  
This study was funded by the National Natural Science Foundation of China (No. 52079107).  
Not applicable.  
The data that support the findings of this study are available from the corresponding author upon reasonable request.  
The authors declare that they have no conflict of interest. The funders had no role in the design of the study, in the collection, analyses, or interpretation of data, in the writing of the manuscript, or in the decision to publish the results.  
The following symbols are used in this paper:  
\begin{tabular}{l l} \(A\) & Pipe cross-sectional area (m\({}^{2}\)); \\ \(\mathbf{A},\overline{\mathbf{A}}\) & Coefficient matrix and the linearized coefficient matrix; \\ \(c\) & Water hammer wave speed in the pipeline (m); \\ \(C_{0},C_{1},C_{2}\) & Weighting coefficients; \\ \(D\) & Pipe diameter (m); \\ \(f\) & Pipeline resistance coefficient; \\ \end{tabular}
## 3 Methodology
### Hyperspectral Data  
Table 1 summarized the acquiring DOY (day of year) of 18 cloud free L1 Gst Hyperion products. The Hyperion L1 Gst products were acquired for 196 calibrated wavebands from the 242 available wavebands and excluded the zero data, VNIR/SWIR overlap, and the strong water vapor absorption bands 1-7, 58-78, and 225-242. Bands 8-57 and 79-224 included in the analysis are in the 427-925 nm (visible and near-infrared (VNIR)) and 933-2396 nm (shortwave infrared (SWIR)) regions of the electromagnetic spectrum, respectively. The signal-to-noise ratio (SNR) for Hyperion changes from 190 to 40 as the wavelength increases. Wavelength windows from 1356 to 1466 nm and 1810 to 2012 nm were eliminated due to strong disturbance by atmospheric vapor and high noise [41, 42]. The main spectral regions chosen in our study were 490-1336 nm, 1477-1790 nm, and 1981-2355 nm. Hyperion Level 1 data products were calibrated to sensor radiance (Wm\({}^{-2}\cdot\)SR\({}^{-1}\cdot\)um\({}^{-1}\)).  
Radiometric corrections were done for Level 1 radiance images to achieve a uniform calibration gain for each band and enhance interpretation of radiance spectra. Geometric corrections were also conducted for Level 1 L1 Gst products. Bands were transformed to canopy reflectance images using the MODTRAN4-based atmospheric correction algorithm Fast Line-of-sight Atmospheric Analysis of Spectral Hypercubes (FLAASH) built into the Environment for Visualizing Images (ENVI) software.  
\begin{table}
\begin{tabular}{c c c c c} \hline
**Year** & **Spring** & **Summer** & **Fall** & **Winter** \\ \hline
2008 & No data & 166, 179, 189, 207 & 230, 271 & 335, 353, 358 \\
2009 & No data & 138, 210 & 236, 241 & 5, 23, 308, 326, 344 \\ \hline \end{tabular}
\end{table}
Table 1: The acquisition day of year (DOY) of Hyperion images used for this study.  
Reflectance spectra were then extracted and averaged from the 1 km\({}^{2}\) square region, which included the eddy covariance tower at its center. The spectral data were extracted and averaged for the same region.
# Fish Consumption Frequency in the Adult Population in Poland
## 2 Materials and Methods  
### Study Population  
This study was a part of the Nationwide Dietary Cross-Sectional Survey in Poland, conducted from July 2019 to February 2020 in a representative nationwide sample of adolescents (aged 10-17 years) and adults (aged \(\geq\) 18 years) according to the European Food Safety Authority (EFSA) guidance on the EU Menu methodology [19, 20]. It included assessment of dietary habits, nutritional status, and physical activity level. The study protocol was approved by the Bioethics Committee at the Institute of Food and Nutrition in Warsaw, Poland (approval dated 4 June 2018). Participation in the study was voluntary. Written informed consent to participate in the study was obtained from each respondent.  
The sample selection procedure consisted of the stratification of the Polish population and the random selection of individuals. Subjects were randomly selected from the PESEL register (the national register of inhabitants in Poland) [21]. The stratified sampling method was used taking into account such demographic details as gender (male, female), age (7 age cohorts), the size of the place of residence, and the territorial distribution within voivodships (16 voivodships, 9 subdivisions of localities). All the steps taken to conduct the study were described in the report published by EFSA [22].  
Individuals that were hospitalized and/or were following enteral and parenteral nutrition because of their health conditions, and individuals whose mental condition made it impossible to obtain reliable information (neurodegenerative diseases, drunkenness, or state after taking drugs and other stimulating substances) were excluded from the study.  
To avoid unforeseen circumstances or refusals, and to ensure that the planned number of people was reached, 10 times more people were randomly selected than the planned number of respondents. If a participant refused to participate in the study, withdrew from the study, or met the exclusion criteria, the next person in the group was selected. Interviewers contacted 4249 persons and the response rate was 57%. Data were collected from 2432 adolescents and adults, but only adults (persons \(\geq\) 18 years old) were included in the analysis of the fish consumption frequency. Complete data on fish consumption frequency were collected from 1489 adults (722 males, 767 females).
# An Efficient Ultra-Tight GPS/RISS Integrated System for Challenging Navigation Environments
###### Abstract  
The Global Positioning System (GPS) provides an accurate navigation solution in the open sky. However, in some environments such as urban areas or in the presence of signal jamming, GPS signals cannot be easily tracked since they could be harshly attenuated or entirely blocked. This often requires the GPS receiver to go into a signal re-acquisition phase for the corresponding satellite. To avoid the intensive computations necessary for the signal re-lock in a GPS receiver, a robust signal-tracking mechanism that can hold and/or rapidly re-lock on the signals and keep track of their dynamics becomes a necessity. This paper augments a vector-based GPS signal tracking system with a Reduced Inertial Sensor System (RISS) to produce a new ultra-tight GPS/INS integrated system that enhances receivers' tracking robustness and sensitivity in challenging navigation environments. The introduced system is simple, efficient, reliable, yet inexpensive. To challenge the proposed method with real jamming conditions, real experiment work was conducted inside the Anechoic Chamber room at the Royal Military College of Canada (RMC). The Sprient GS86700 signal simulator was used to generate GPS signals, and an INS Simulator is used for simulating the inertial measurement unit (IMU) to generate the corresponding trajectory raw data. The NEAT jammer, by NovAtel, was used to generate real jamming signals. Results show a good performance of the proposed method under real signal jamming conditions.  
GPS; INS; ultra-tight integration; jamming Article
## 4 Results and Discussions
### EM Properties of PP/MWCNT Nanocomposite  
The real permittivity values vary minimally based on frequency, but increasing the MWCNT loading in PP increases the real component due to polarization. The actual permittivity percentage ranges from 3.5 to 14, with denser networks due to higher concentrations of PP/MWCNT, as presented in Figure 8. Complex permittivity increases from 0 to 2.5 wt%, and then decreases at higher concentrations. Polymer composites show a rise in the imaginary permittivity component due to frequency, affecting their dielectric loss (\(\varepsilon^{\prime\prime}\)). This is due to conductive losses boosted by conductive particulates. As the PP/MWCNT mass fraction increases, particle distance decreases, enhancing conductive current generation. \(\varepsilon^{\prime\prime}\) increases to 2.7 wt%, reducing energy storage capacity. The PP/MWCNT composite has the highest dielectric loss at a 2.7 wt% concentration.  
Figure 8: Variation of **(a)** Real part of complex relative Permititivity and **(b)** Imaginary part of complex relative permittivity of PP/MWCNT nanocomposite in X-band.  
Figure 7: Variation of **(a)** Real part and **(b)** Imaginary parts of complex relative permittivity **(c)** Real part and **(d)** Imaginary parts of complex relative permeability of PP-GNP composites in X-band.
# Design, Modeling, and Analysis of Piezoelectric-Actuated Device for Blood Sampling
## 4 Results of the Micropump Simulation
### Flow Analysis with Flushed Microneedle  
The effect of capillarity was analyzed by carrying out numerical simulation. It was found that the capillary force is not sufficient to suck the blood and deliver it to the biosensor location. Therefore, capillary forces were neglected during the simulations.  
Simulation of the micropump was carried out with flushed microneedle, applying sinusoidal voltage, as given in Equation (7), to the actuator for studying behavior under harmonic excitation (dynamic mode):  
\[V_{p}=V\sin\left(2\pi\textit{ft}\right) \tag{7}\]  
where \(V_{p}\) is the applied voltage, \(V=2.5\) V,\(f\) is the applied frequency (35,338 Hz), and \(t\) is the time.  
Figure 3a shows flushed microneedle attached to the pump chamber. Streamlines can be seen diverting in all the directions inside the pump chamber (Figure 4a). Location of the biosensor was considered as 1 mm away from the microneedle. The reason for the location is that the extracted blood gets diverted and then aligns with the bottom of the pump chamber at some downstream location from the microneedle outlet as shown. It would ensure sufficient volume of blood reaching the biosensor. Upstream of this location, fluid was not attached to the pump chamber bottom wall. The location of reattachment depends on several variables, namely, pressure difference, actuation voltage, and frequency. The smaller the locational distance, the lesser will be the time of actuation for a particular set of these parameters.  
[PERSON] et al. [34] reported that a blood volume of 0.6-1.1 uL is required at the biosensor for the diagnosis. Numerical simulation of the base case provided a volume flow rate of 3.4 uL/s (-at 1.2 m/s) at the pump chamber inlet, which is more than three times the required volume. However, only 0.471 uL/s was found to be available at the biosensor location. The reason for the difference in extracted and available volume flow rate is due to the extracted blood getting spread all over in the pump chamber.
## 3 Methodology
### Correlation between NEP and Climate Factors  
In this study, in order to further explore the correlation mechanism between the spatiotemporal change law of \(NEP\) and the change of climate factors in the CGE, the spatial analysis method based on the spatial grid, including the correlation coefficient and partial correlation coefficient, was used to calculate the correlation between the change in the \(NEP\) spatial pattern and temperature and precipitation and to analyze the response mechanism between \(NEP\) and climate change.  
The correlation coefficient was calculated by the following formula [38; 39]:  
\[R_{xy}=\frac{\sum_{i=1}^{n}\left[\left(x_{i}-x_{p}\right)\left(y_{i}-y_{p} \right)\right]}{\sqrt{\sum_{i=1}^{n}\left(x_{i}-x_{p}\right)^{2}\sum_{i=1}^{n} \left(y_{i}-y_{p}\right)^{2}}}\]  
where \(R_{xy}\) represents the correlation between variables \(x\) and \(y\); \(x_{i}\) is the \(NEP\) in year \(i\); \(y_{i}\) is the value of variable \(y\) in year \(i\); \(x_{p}\) is the average value of \(NEP\) from 2010 to 2020; \(y_{p}\) is the average value of variable \(y\) from 2010 to 2020 and \(n\) is the estimated number of years.  
The partial correlation coefficient was obtained by the following formula to analyze the response of \(NEP\) to another variable when one variable in precipitation or temperature was fixed [40].  
\[r_{xy,z}=\frac{r_{xy}-r_{xz}r_{yz}}{\sqrt{\left(1-r_{xz}\right)^{2}\left(1-r_{ yz}\right)^{2}}}\]  
where \(r_{xy}\), \(r_{xz}\) and \(r_{yz}\) represent the cross-correlation coefficient between the variation \(x\) and \(y\), \(x\) and \(z\) and \(y\) and \(z\), respectively, and \(r_{xy,z}\) is the cross-correlation coefficient between \(x\) and \(y\) when the value of \(z\) is fixed.  
In addition, the T-test method was used to test the significance of the correlation coefficient and partial correlation coefficient of each variable [41]:  
\[t=\frac{r_{xy,z}}{\sqrt{1-r_{xy,z}^{2}}}\sqrt{n-m-1}\]  
The significance level was taken as \(\alpha\)= 0.05, and the degree of freedom was 11. According to the significance level, results were divided into significant positive correlation (\(R>0\), \(p<0.05\)), insignificant positive correlation (\(R>0\), \(p\geq 0.05\)), significant negative correlation (\(R<0\), \(p<0.05\)) and insignificant negative correlation (\(R<0\), \(p\geq 0.05\)). Then, the CGE was divided into four different areas according to different significance levels.
# Supervised Blockchain Anonymous Transaction Model Based on Certificateless Signcryption
## 6 Scheme Analysis and Proof  
### Security Analysis  
1. Anonymity: In the CLSC_SAT model, the real identity \(RID_{i}\) of a user can be traced in two ways. The first method is \(RID_{i}=\alpha_{i}+rEID_{i,1}\), where the user's anonymous identity \(EID_{i}\) is composed of a secret value \(e_{i}\) chosen by the user and the tracking key \(r\). Only entities possessing \(e_{i}\) or \(r\) can compute \(rEID_{i}\). This process is equivalent to solving the CDH hard problem, i.e., given \(M_{pub}=rP\) and \(EID_{i,1}=e_{i}P\), solving \(rEID_{i,1}=re_{i}P\), which is computationally infeasible. The second method is \(RID_{i}=EID_{i,2}\oplus H(rEID_{i,1}||EID_{i,1}||M_{pub}||VM_{i})\). Since only the MR possesses \(r\), other nodes cannot recover \(RID_{i}\) using this method. Additionally, \(RID_{i}\) is not stored in the EIDList. Even if an attacker A obtains \(\{EID_{i},\alpha_{i}\}\) from the EIDList, they cannot reveal the user's real identity \(RID_{i}\) without solving the CDH problem or stealing the tracking private key \(r\). Therefore, the CLSC_SAT model satisfies anonymity.
2. Traceability: When signature verification fails or a miner node detects an anomalous transaction, the user's \(RID_{i}\) is traced and revealed. The MR retrieves the anonymous identity \(EID_{i}=\{EID_{i,1},EID_{i,2}\}\) of the user involved in the anomalous transaction and uses the tracking key \(r\) to compute \(RID_{i}=\alpha_{i}+rEID_{i,1}\) or \(RID_{i}=EID_{i,2}\oplus H(rEID_{i,1}||EID_{i,1}||M_{pub}||VM_{i})\) to recover \(RID_{i}\). The malicious user's \(RID_{i}\) is then disclosed. Thus, the CLSC_SAT model satisfies traceability.
3. Forward and Backward Security: In the CLSC_SAT model, even if an adversary A obtains the signature information \(\sigma_{i}=\{U_{i},S_{i},C_{i,1},C_{i,2}\}\), where \(U_{i}=u_{i}P\), \(S_{i}=(x_{i}+d_{i})h_{i,4}+u_{i}\) and \(h_{i,4}=H_{4}(EID_{n},C_{i},U_{i},X_{B},t_{i})\), the randomness of \(u_{i}\) and \(t_{i}\) ensures that each transaction's signature is unique. It is impossible to infer  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**User** & **Anonymous Identity Index** & **Anonymous Identity Address** \\ \hline A & \(\alpha_{A}\) & \(EID_{A}\) \\ B & \(\alpha_{B}\) & \(EID_{B}\) \\ C & \(\alpha_{C}\) & \(EID_{C}\) \\... &... &... \\ U & \(\alpha_{U}\) & \(EID_{U}\) \\ \hline \hline \end{tabular}
\end{table}
Table 2: User anonymous identity tracing list.  
Figure 2: Process of supervision and tracing.  
the content of previously or subsequently sent messages using the current transaction's signature information. Therefore, the CLSC_SAT model satisfies forward and backward security.
# Impact of Latency on QoE, Performance, and Collaboration in Interactive Multi-User Virtual Reality
###### Abstract  
Interactive, multi-user experiences are meant to define the present and future of Virtual Reality (VR). Such immersive experiences will typically consist of remote collaborations where content is streamed and/or synchronized over a network connection. Thus, real-time collaboration will be key. In this light, the responsiveness of the system and the network will define the overall experience. As such, understanding the effect of network distortions, especially related to time delay, on end-user's perception (in terms of Quality-of-Experience (QoE)), performance, and collaboration becomes crucial. The existing literature, however, has mostly focused on network requirements from a system point-of-view, where the key performance parameters are only provided in the form of Quality-of-Service (QoS) parameters (such as end-to-end latency). However, the translation of these network impairments to the end-user experience is often omitted. The purpose of this paper is to fill the gap by providing a thorough investigation of the impact of latency on the perception of users while performing collaborative tasks in multi-user VR. To this end, an experimental framework was designed, developed, and tested. It is based on a multi-device synchronizing architecture, enabling two simultaneous users to work together in a gamified virtual environment. The developed test environment also allows for the identification of the most prominent network requirements and objective analysis for each traffic link. To experimentally investigate the impact of latency on user perception, a user study was conducted. Participants were paired and asked to perform the collaborative task under different latency-prone scenarios. The results show that users are able to easily distinguish between distorted and non-distorted network configurations. However, making a distinction between different manifestations of latency is much less straightforward. Moreover, factors such as the user's role in the experience and the required task, and the level of interactivity and movement have an important influence on the subjective level of perception, the strength of the user's preferences, and the occurrence of cybersickness. In contrast, no significant differences in objective metrics, such as system performance and user completion time were observed. These results can support the creation of collective QoE metrics that model the group as a whole rather than each individual separately. As such, this work provides an important step to dynamically counteract any drops in group dynamics and performance by means of smart interventions in the transmission system and/or virtual environment.  
collaborative VR; multi-user; QoE; performance; network impairments; latency; interactivity +
Footnote †: journal: _Sci._**2024**, 14, 2290. [[https://doi.org/10.3390/app14062290](https://doi.org/10.3390/app14062290)]([https://doi.org/10.3390/app14062290](https://doi.org/10.3390/app14062290))