esa-sceva/satcom-chunk-collection huggingface dataset:
# Electronic Beam Steering Metamaterial Antenna with Dual-Tuned Mode of Liquid Crystal Material
###### Abstract  
In this study, a dual-tuned mode of liquid crystal (LC) material was proposed and adopted on reconfigurable metamaterial antennas to expand the fixed-frequency beam-steering range. The novel dual-tuned mode of the LC is composed of double LC layers combined with composite right/left-handed (CRLH) transmission line theory. Through a multi-separated metal layer, the double LC layers can be loaded with controllable bias voltage independently. Therefore, the LC material exhibits four extreme states, among which the permittivity of LC can be varied linearly. On the strength of the dual-tuned mode of LC, a CRLH unit cell is elaborately designed on three-layer substrates with balanced dispersion values under arbitrary LC state. Then five CRLH unit cells are cascaded to form an electronically controlled beam-steering CRLH metamaterial antenna on a downlink Ku satellite communication band with dual-tuned characteristics. The simulated results demonstrate that the metamaterial antenna features' continuous electronic beam-steering capacity from broadside to \(-35^{\circ}\) at 14.4 GHz. Furthermore, the beam-steering properties are implemented in a broad frequency band from 13.8 GHz to 17 GHz, with good impedance matching. The proposed dual-tuned mode can make the regulation of LC material more flexible and enlarge the beam-steering range simultaneously.  
liquid crystal; metamaterial antenna; dual-tuned; beam steering +
Footnote †: journal: Sensors
## 3 Results
### Inter-Satellite MEO-GEO Link  
In MEO-GEO satellite link communications, Reed-Solomon codes are frequently used due to their ability to correct block errors caused by noise or other perturbations specific to space channels [26]. In the results below, we have used a common RS (255, 223) approach, where each block has 255 symbols, of which 223 are information symbols and 32 are redundancy symbols for correction, allowing the correction of up to 16 erroneous symbols per block. These parameters provide a balance between link robustness and spectral efficiency, being suitable for high-fidelity inter-orbit communications.  
For this simulation, in Table 8, we highlighted the coordinates of the two satellites used for the communication link, and in Table 9 we highlighted the parameters of the MEO transmitter, GEO receiver, and the link, which are typical values that could be present in such a case.  
\begin{table}
\begin{tabular}{c c c c c} \hline
**LEO Satellite** & **Value** & **Link** & **Value** & **MEO Satellite** & **Value** \\ \hline Tx feeder loss [dB] & 1 & Frequency [GHz] & 10 & Interference loss [dB] & 2 \\ Other Tx losses [dB] & 2 & Bandwidth [MHz] & 15 & Rx G/T [dB/K] & 20 \\ Tx HPA power [dBW] & 15 & Bit rate [Mbps] & 8 & Rx feeder loss [dB] & 1 \\ Tx HPA OBO [dB] & 4 & Required Eb/N [dB] & 5 & Other Rx losses [dB] & 1 \\ Tx antenna gain [dBi] & 30 & Availability [\%] & 99.9 & \\  & & Polarization mismatch [deg] & 3 & \\  & & Implementation loss [dB] & 1 & \\  & & Antenna mispointing loss [dB] & 2 & \\  & & Radome loss [dB] & 0 & \\ \hline \end{tabular}
\end{table}
Table 7: The satellite transmitter (LEO), receiver (MEO), and link proprieties.  
Figure 8: Link margin vs. modulation scheme for LEO-MEO connection.  
Figure 7: BER Analysis for PSK, DPSK, QAM and OFDM modulation using a 1/2 rate LDPC code.  
In Figure 9 we see that the BER analysis using the previously mentioned code reflects the gain coding due to performance optimization, compared with the theoretical analysis from Figure 4. For example, 16 DPSK modulations have an Eb/No value of 21.4 dB for a BER of \(1\times 10^{-6}\). After we encode the data, for the same BER value and the same type of modulation, we get an Eb/No of 16.7 dB, so a coding gain of 4.7 dB.  
As can be seen in this situation in Figure 10, OFDM modulation offers higher overall performance. The biggest link margin from the other types of modulation is still offered by BDPSK, but it comes with the cost of a limitation in terms of data transfer capability.
# RIS-Assisted Network Slicing Resource Optimization Algorithm for Coexistence of eMBB and URLLC
## 3 Problem Formulation
### URLLC Allocation Problem
Constraint (21) means that the allocated eMBB and URLLC power should not exceed the total power of the BS. Constraint (22) indicates the reception indicator of the URLLC packet. Constraint (23) demonstrates that if URLLC packet \(l\) is received, i.e., \(k_{l}^{m}=1\), the number of RBs allocated to URLLC packet \(l\) must be greater than zero, i.e., \(I_{l}^{m}>0\).
## 2 Materials and Methods
### HPLC-Dad-Esi-Ms Identification of the Phenolic Composition
#### 2.6.2 High-Performance Liquid Chromatography (HPLC DAD-ESI\({}^{+}\)) Conditions  
An Agilent 1200 HPLC system equipped with an autosampler, a quaternary pump, solvent degasser, diode array UV-Vis detector (DAD), and single-quadrupole mass detector (MS) Agilent model 6110 (Agilent Technologies, Santa Clara, CA, USA) was used to identify and quantify phenolic compounds. Compound separation was performed on a Kinetex XB C18 column, dimensions 4.6 \(\times\) 150 mm, with 5 m particles (Phenomenex, Torrance, USA), using the following gradient mobile phases: (A) water +0.1% acetic acid and (B) acetonitrile +0.1% acetic acid over 30 min, at a temperature of 25 \({}^{\circ}\)C, with a flow rate of 0.5 mL/min. Gradient (% B): 0 min, 5% B; 0-2 min, 5% B; 2-18 min, 5-40% B; 18-20 min, 40-90% B; 20-24 min, 90% B; 24-25 min, 90-5% B; 25-30 min, 5% B. Spectral values were recorded in the range of 200-600 nm for all peaks. Chromatograms were recorded at wavelengths \(\lambda=280\), 340, and 520 nm. Various phenolic compounds were identified by comparing the retention times, UV visible and mass spectra of unknown peaks with reference standards [24]. For MS, the positive ESI ionization mode was used for a full scan. The working conditions were as follows: Temperature 35 \({}^{\circ}\)C, nitrogen flow rate 7 L/min, and \(m/z\) 120-1200, with a capillary voltage of 3000 V. Data acquisition and result interpretation were performed using Agilent ChemStation software (Rev B.02.01-SR2 [260], Palo Alto, CA, USA) [25].
## 4 Dataset
### Characteristics  
The data dumps contain two tabular files with respect to the characteristics of each listing; one that contains 16 basic features and another that contains 106 very detailed additional features. For the purpose of the current analysis, the basic features have been considered to be sufficient. They can be grouped into the following categories:  
* Host details (name, id, number of properties managed)
* Listing details (listing id, description, exact location, neighborhood, property type)
* Basic availability details (availability throughout the year, minimum nights per stay)
* Price per night (in USD)
* Aggregated review details  
Table 1 below summarizes the evolution of three key features of the examined dataset for the City of Athens, Greece; (i) the total number of listings (ii) the mean price per night (iii) the mean number of available days per year.  
Even though there is a scarcity of data in the earlier years, it is obvious that platform listings have witnessed an exponential growth from around 2000 to almost 10,000 (a 5-fold increase) in the three-year period between 2015 and 2018, followed by a small but steady linear growth since. Further analysis on the type of property listed on the platform (Table 2) reveals that, since the beginning, the overwhelming majority of them (more than 80%) are entire homes or apartments, while recently, an increase in listings described as Hotel Rooms is also visible. The above observation, in conjunction with the large average listing availability on the platform (5 th column of Table 1) lead to the conclusion that properties on the Airbnb platform are another, concealed & unregulated form of touristic accommodation, thereby rendering the \"sharing economy\" claims extremely weak for the case of the City of Athens, Greece. Lastly, the mean accommodation price seems to be stabilized around $60-$65 per night or $1800-$2000 per month, which is at least 3 times higher that the average monthly LTR price and also a justification for the reason home owners prefer to list their properties on STR platforms than renting them to regular tenants.
## 2 Methodology
### PEV and Charger Type  
The initial considerations have to do with the PEV and Charger types. It was assumed that the percentage of PEVs that would charge at the microgrid would consist of 75% passenger EVs, 15% electric two wheelers (ETW) and 10% electric buses (EB). PEV appearance possibility is equal to its related market share. [17]. Their technical characteristics and charging limitations are shown in Table 1. The values for the charging limitation that were not known appear in Table 1 with the sign \"*\"and a value which is considered suitable is assigned to them [18].  
In addition, it is considered that all PEVs support bidirectional energy flow and the charging and discharging have the same power limitations. Two types of chargers are considered, an alternative current (AC) of 22 kW and a direct current (DC) of 100 kW.
## 4 Conclusions  
In conclusion, based on the relevant obtained results, the melting process of Sn-P alloys must be performed in a clean and inert environment, due to the activity of constituent elements that can cause other undesirable chemical reactions and connections. The temperature and melting time have to be controlled and monitored continuously. During the melting, the temperature increased, and while the holding time of approx. 21 min at a constant temperature seemed sufficient to carry out a chemical reaction between tin and phosphorus, the difference in the percentage content of phosphorus in the cast sample was influenced by the temperature. However, the temperature of 850 \({}^{\circ}\)C was proved to be the most suitable for casting the SnP\({}_{2}\) pre-alloy because, at this temperature, the highest percentage of red phosphorus was contained in tin. In the process of melting this pre-alloy, the temperature cannot be decreased below 850 \({}^{\circ}\)C before casting if the aim is to achieve the highest possible phosphorus content during melting.  
The dress taken from each melt every hour was weighed and recorded. The weighing process and investigation led to results for dress from two solder baths: SAC305 (A) and SAC305 with the addition of phosphorus (B). They are shown in Figure 14. The quantity of dress, resulting from solder bath for B, is 35% lower than the resulting quantity of dress from solder bath A. The formation of oxidic phases is undesirable for the further use of these alloys in the form of solders. The addition of tin-phosphorus pre-alloy deoxidation is one option to reduce the formation of dress on the surface of the melt during the production of solder. It is important to mention that the advantage of phosphorus in solder is not only a reduction in the weight of the smeling by-product (dross) in the manufacture of solder. The Sn-P pre-alloy has a high use in wave soldering, where it is gradually added to the melt in small quantities, resulting in a significant reduction in the amount of oxides on the surface of the melt in the process of PCB board soldering.  
**Author Contributions:** Conceptualization, J.K. and J.V.J.; methodology, J.K.; software, J.K.; validation, J.K., J.V.J. and J.V.; formal analysis, J.K.; investigation, J.K.; resources, J.K.; data curation, J.K.; writing--original draft preparation, J.K.; writing--review and editing, J.V.J. and J.V.; visualization, J.K.; supervision, J.V.; project administration, J.K.; funding acquisition, J.V.J. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research received no external funding.  
**Institutional Review Board Statement:** Not applicable.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** The data presented in this study are available on request from the corresponding author. The data are not publicly available due to privacy.  
Figure 14: Quantity of dress from melts A (without the addition of Sn-P pre-alloy) and B (with the addition of Sn-P pre-alloy).
# Optimal Design of One-Sided Exponential Adaptive EWMA Scheme Based on Median Run Length
## 2 Exponential Monitoring Schemes for TBE Data
### One-Sided Exponential AEWMA Schemes for TBE Data
\right.,\] (15) where \(\lambda^{-}\) is the \(t\)th statistic (the starting value \(A_{0}^{-}=1\)), and \(\omega(e_{t})=\phi(e_{t})/e_{t}\) where \(\phi(e_{t})\) is a score function \[\phi(e)=\left\{ \begin{array}{ll}e+(1-\lambda^{-})k&\text{if }e<-k\\ \lambda^{-}e&\text{if }|e|\leq k\\ e-(1-\lambda^{-})k&\text{if }e>k\end{array} \right.,\] (16) where \(\lambda^{-}\) is the \(t\)th statistic (the starting value \(A_{0}^{-}=1\)), and \(\omega(e_{t})=\phi(e_{t})/e_{t}\) where \(\phi(e_{t})\) is a score function \[\phi(e)=\left\{ \begin{array}{ll}e+(1-\lambda^{-})k&\text{if }e<-k\\ \lambda^{-}e&\text{if }|e|\leq k\\ e-(1-\lambda^{-})k&\text{if }e>k\end{array} \right.,\] (17) where \(\lambda^{-}\) is the \(t\)th statistic (the starting value \(A_{0}^{-}=1\)), and \(\omega(e_{t})=\phi(e_{t})/e_{t}\) where \(\phi(e_{t})\) is a score function. For simplicity, [PERSON]'s score function is used, as suggested by [PERSON] and [PERSON] (see [8]) \[\phi(e)=\left\{ \begin{array}{ll}e+(1-\lambda^{+})k&\text{if }e<-k\\ \lambda^{+}e&\text{if }|e|\leq k\\ e-(1-\lambda^{+})k&\text{if }e>k\end{array} \right.,\] (18) where the threshold parameter \(k\geq 0\). * A lower-sided exponential AEWMA scheme is suggested to detect a decrease in the process parameter (\(0<c<1\)), \[\begin{split} A_{t}^{-}&=\text{min}(B^{-},A_{t-1}^{-}+\phi(e_{t}))\\ &=\text{min}(B^{-},\omega(e_where the threshold parameter \(k\geq 0\). As \(k\) approaches infinity (\(\phi(e)\approx\lambda e\)), the AEWMA scheme reduces to the EWMA-type scheme. Conversely, as \(k\) approaches zero (\(\phi(e)\approx e\)), the AEWMA scheme reduces to the Shewhart-type scheme.
## 3 Results
### Magnetic Properties
#### 3.3.3 Epr  
EPR measurements were performed to obtain additional information about the effect of size and aggregation of the NPs on their magnetic properties. The EPR spectrum of each type of sample shows only one rather broad peak (Figure 8). These spectra are similar to those reported in the literature for magnetite NPs of similar sizes [7,8,23]. The peak of sample C is narrower and shifted with respect to the peaks of samples A and B, which have similar width and position (Table 6). The shift of the resonance peak can be ascribed to the smaller diameter of NPs C compared to NPs A and B. The magnetic dipoles of NPs generate an internal magnetic field which adds to the applied field [7] thus the intensity of the external field corresponding to the resonance peak is lower. The internal field is larger for sample A (and sample B) than for sample C since the magnetization in the former case is larger than in latter case and therefore the resonance occurs at a lower field.  
Both the smaller size and less relevant magnetic dipole-dipole interactions between adjacent NPs can explain the narrower peak width of sample C compared to samples A and B [46]. Hence, EPR results are consistent with the ZFC-FC curves showing a higher Tb of sample A and B compared to C due to their larger size and larger magnetic dipole-dipole interactions. The resonance peaks are slightly asymmetric with a height of the maximum larger than the height of the minimum. The asymmetry ratio (defined as the ratio of the maximum to the minimum) is larger than 1 for all the samples. This is consistent with the negative cubic magnetocrystalline anisotropy [8].
# NFC Tag Awareness and Its Visual Implementation on Food Packaging: Case Study in Slovenia
###### Abstract
In the case study by [PERSON] et al. (2018) on a smart yogurt filling system, NFC, as one of the emerging technologies of Industry 4.0 (I4.0), was found to enhance customer satisfaction, reduce the expenditure of time and effort, lower error rates, and minimize waste. The advanced technologies of I4.0 are being progressively adopted in the dairy sector, making significant changes in the production of milk, cheese, and other dairy products ([PERSON] et al., 2018). In the digital information age, people pay more attention to the experience of interactive concepts in daily life; thus, to combine the interaction concept with packaging the needs of the consumers must also be considered in package design ([PERSON] et al., 2018). The graphic design of packaging involves creating visual content to convey specific information to the consumers, a strategy which is delivered through color packaging, typography, graphic shapes, and images ([PERSON] et al., 2018). It directly influences consumers' perception of the product through efficient communication and can influence their purchasing decision. To observe consumer behavior, eye-tracking technology is used. This technology may provide graphic representations of eye movements, such as heat maps (fixation concentration) and gaze plots (observations). It has been utilized in numerous studies to acquire a better understanding of customers' visual attention and, as a result, a better understanding of consumer behavior, information acquisition, and decision-making. For example, it has been used to verify packaging flaws prior to the product launch ([PERSON] et al., 2018), determine the effects of packaging characteristics on consumer attention and packaging evaluation ([PERSON] et al., 2018), identify packaging observation patterns ([PERSON] et al., 2018), understand the effect of visual influence on in-store purchasing decisions ([PERSON] et al., 2018), determine which characteristics attract consumer attention more ([PERSON] et al., 2018), and to understand the attractiveness of packaging ([PERSON] et al., 2018) and the impact of visual stimuli on consumers' decision-making strategies ([PERSON] et al., 2018). In the research by [PERSON] et al. (2018), eye-tracking was used to analyze the consumers' attention to functional food labeling of probiotic milk. Our research focuses on NFC knowledge and on the use and placement of NFC tags to gain a better understanding of consumer knowledge and consumer interaction with NFC tags. The following research questions were of interest:  
1. Do Slovenian consumers recognize and know the meaning of NFC tags? 2. To what extent do consumers utilize NFC tags? 3. How does the design of NFC tags on food packaging, in terms of messaging and placement, influence consumer interaction and visibility?
# Virtual Grid-Based Routing for Query-Driven Wireless Sensor Networks
## 3 VGRQ: The Proposed Routing Mechanism
### Phases of VGRQ  
The VGRQ works in five phases: (i) grid construction, in which multiple grid cells are constructed in the sensor field; (ii) cell header election, in which a cell header is elected for each grid cell; (iii) updating mobile sink position, where the mobile sink provides its location to the cell headers along the chains; (iv) query transmission, where the mobile sink sends a query packet to acquire the data; and (v) data transmission, where sensor nodes of AoI send the data to their respective CHs. The detailed description of each phase is discussed below.
## 7 Conclusions  
This paper presents emulation strategies and economic dispatch for inverter-based RG units under VSG control participating in multiple temporal frequency control homogeneously and jointly with traditional synchronous generators. Based on the previous, the conclusions are made:  
1. Generation units can be divided into two parts: the primary energy input and the electric power generation. For PEI-based renewable generation, the external properties can be designed through the programmable supplementary controller to emulate those of traditional synchronous generators. The IBG operates mainly in two modes: the MPPT mode and the VSG mode. Based on the proposed VSG algorithm, the IBG can perform multiple temporal frequency control. Therefore, the IBG could participate in system frequency regulation. 2. The uncertainty of renewable generation is assumed to obey Gaussian distribution. Based on the properties of Gaussian distribution, the generation uncertainty of VSG-RG is eliminated by setting \begin{table}
\begin{tabular}{c c c} \hline
**Operation Mode** & **RG Unit under MPPT** & **RG Unit under VSG** \\ \hline Operation cost (\$) & 22,651 & 22,350 \\ \hline \end{tabular}
\end{table} 
Table 7: Total operation cost. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & **1** & **2** & **3** & **4** & **5** & **6** \\ \hline Renewable output (MW) & 50.68 & 51.66 & 59.72 & 61.47 & 64.51 & 70.34 \\ \hline Load served (MW) & 370 & 330 & 290 & 260 & 280 & 350 \\ \hline Renewable penetration & 13.7\% & 15.7\% & 20.6\% & 23.6\% & 23.0\% & 20.1\% \\ \hline \hline \end{tabular}
\end{table} 
Table 8: The renewable penetration in the case study time step. \begin{table}
\begin{tabular}{c c c c} \hline \hline Maximum Penetration Level (\%) & 13.9 & 23.6 & 55.6 \\ \hline Operation cost with MPPT-based IBG (\$) & 24,782 & 22,651 & Infeasible \\ \hline Operation cost with VSG-based IBG (\$) & 24,544 & 22,350 & 18,101 \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Predicted renewable generation and load. an upper output limit at each time period. After the transformation, the generation profiles of the renewable units are homogeneous with those of SGs, and the renewable generation could be scheduled as system reserves. 3. A generation-reserve co-optimization model was built and solved to acquire the economic dispatch schemes. Based on the results, the integration of VSG-RG will not aggravate the requirements of the system reserves. Furthermore, VSG-based IBG can be allocated part of the reserve, decreasing the burden of other SGs. Towards power systems with high-penetration renewable generation or even 100% renewables, the proposed approach provides a preliminary solution. This work was carried out by [PERSON] under the supervision of [PERSON]. The editing was mostly done by [PERSON] All authors have read and agreed to the published version of the manuscript. This research was funded by National Natural Science Foundation of China-Hebei on the project of \"Research on inertia characteristics and control strategy for primary frequency and voltage regulation of DFIG\" (No. E201802134). The authors declare