esa-sceva/satcom-chunk-collection huggingface dataset:
###### Abstract  
Simultaneously enhancing multiple antenna performance parameters is a demanding task, especially with a challenging set of design goals. In this paper, by carefully deriving a compatible set of enhancement techniques, we propose a compact/lightweight/low-cost high-performance L-band octagonal cavity-backed hybrid antenna with multiple attractive features: dual-polarization, wide impedance bandwidth, low cross-polarization, high gain, and high aperture efficiency. The ground cavity is octagonal, which allows the antenna to have a small footprint, and, more importantly, low cross-polarization and high aperture efficiencies when compared to a commonly-used square design. The hybrid design relies on the resonance merging of two radiating elements, i.e., radiating feedlines and a conductive open prism, to form a wide impedance bandwidth. To permit polarization diversity and low cross-polarization, it is differentially and orthogonally fed. Herein, a series of parametric simulation studies on antenna configurations provide information on how to improve the impedance bandwidth and cross-polarization performance. To verify the simulation studies, an antenna prototype was fabricated and tested. Excellent agreement between the simulated and measured results was reached.
# Routing Protocols for Mobile Internet of Things (IoT): A Survey on Challenges and Solutions
## 4 Solutions to the Issues Faced by RPL during Mobility
### RSSI Based Solutions
#### 4.3.7 DAG-Based Multipath Routing (DMR)  
We note that the RPL faces many open issues based on DODAG construction, DODAG maintenance, and its repair both locally and globally, and computation of rank. To address these problems, the authors [41] proposed DAG-based Multipath Routing Protocol (DMR), which uses _rank_ information and Link Quality Indication (LQI) for constructing DODAG. This approach is adaptable to frequent mobile sensor network topology changes. DIS message is broadcasted by a source node to the sink node to construct a DODAG. After receiving the DIS message, DODAGID is increased by one by the sink node and _rank_ value is initialized to zero. Following, the sink node broadcasts the DIO message for the formation of a new DODAG. After the node receives the DIO message, the node compares its DODAGID with the sender DODAGID. DIO message is regarded for new DODAG construction only if sender DODAGID is greater than receiver DODAGID. To assign the sender as the parent node, the node increases its _rank_ by sender's _rank_+1 and replaces its DODAGID with sender DODAGID.  
In addition, the LQI information is computed based on the RSSI value received from the DIO message for the determination of priority among the same _rank_ nodes. The DODAGID, _rank_, senders ID, and LQI information are saved in the Parent Sibling list (PS-list). Then DIO message is broadcasted which includes _rank_ and DODAGID information. Loop creation is avoided if the senders _rank_ is greater than node _rank_ and senders DODAGID is lesser than node receiver DODAGID. After a predetermined period, the constructed DODAG expires. In a DODAG repair process, PS-list is checked by the node to determine the next node to which data packet should be forwarded. A node with a lower _rank_ and high LQI is chosen as the next node. DODAG node consists of information of the parent node as well as the sibling nodes in the routing table. Following, if the parent node becomes invalid of an intermediate node then reliable data delivery can be maintained by forwarding data packets to sibling nodes. However, when both parent and sibling nodes are not available in the PS-list, the DODAG can be reconstructed by broadcasting a DIS message, hence, broken routes can be repaired both locally and globally. The simulation results show that routing load in DMR is reduced to 65% and data delivery ratio to 97%. The DMR per node reduces average energy consumption by 25% and is the most energy-efficient routing scheme.  
Table 3 shows the working principles, issues addressed, strengths, and weaknesses of solutions under the category 'RSSI-based Solutions'.
## 3 Results and Discussion
### Analysis of Model Optimization Results
#### 3.3.4 Current Deficiencies in Research  
The collation of data represents the foundation upon which the optimization of the SWMM is based. However, due to the complex geographical environment of the Wujin district and time and resource constraints, there remain areas for improvement in the data collection process, which must be acknowledged. The veracity of the terrain data and land use data in some areas must be improved, which may compromise the model's precision. Although a substantial quantity of data has been gathered through uncrewed aerial vehicle (UAV) remote sensing and field measurements, there are some regions where data collection remains insufficient, particularly due to the expanse of the protected area and the intricate terrain.  
Furthermore, meteorological and hydrological data must be monitored for a longer period and updated in real-time. While substantial historical data has been procured from the China Meteorological Administration and automatic weather stations, the data's temporal and spatial resolutions are limited, rendering them inadequate for capturing the nuances of short-term heavy rainfall and localized waterlogging.  
Implementing low-impact development (LID) measures has demonstrated efficacy in reducing surface runoff and enhancing the utilization rate of rainwater. Nevertheless, the selection and design of LID measures must be optimized by specific geographical and climatic conditions, which need to be sufficiently addressed in this study. The design parameters (size, material selection) of rain gardens and permeable pavements require further optimization to achieve optimal results. Additionally, long-term maintenance and management of LID measures necessitate regular maintenance and cleaning of facilities such as rain gardens and permeable pavements to maintain effectiveness. However, this study could have delved into the maintenance strategies and costs associated with these measures.
###### Abstract  
This paper focuses on edge-enabled cloud radio access network architecture to achieve ultra-reliable communication, a crucial enabler for supporting mission-critical machine-type communication networks. We propose coordinated multi-point transmission schemes taking advantage of diversity mechanisms in interference-limited downlink cellular networks. The network scenario comprises spatially distributed multiple remote radio heads (RRHs) that may cooperate through silencing, or by using more elaborated diversity strategies such as maximum ratio transmission or transmit antenna selection to serve user equipment in the ultra-reliable operation regime. We derive an exact closed-form expression for the outage probabilities and expected values of signal-to-interference ratio for silencing, transmit antenna selection and maximum ratio transmission schemes. We formulate rate control and energy efficiency under reliability constraints to test the performance and resource usage of the proposed schemes. Furthermore, we study the impact on average system sum throughput with throughput-reliability trade-off under cooperative communication. Extensive numerical analysis shows the feasibility of ultra-reliable communication by implementing diversity schemes with RRHs cooperation.  
CRAN; diversity; MTC; multi-connectivity; reliability; ultra-reliable communication; URLLC 26 October 2021  
30 November 2021  
1
Footnote 1: [[https://www.mdpi.com/journal/sensors](https://www.mdpi.com/journal/sensors)]([https://www.mdpi.com/journal/sensors](https://www.mdpi.com/journal/sensors))
# Flexible Wearable Heart Rate Monitoring System and Low-Power Design: A Review
## 6 Design of the Flexible Wearable Heart Rate Signals Transmission and Output Module
### Hardware-Algorithm Co-Design for Flexible Wearable Heart Rate Signal Transmission and Output Module
\begin{table}
\begin{tabular}{p{56.9 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline
**Reference** & **Innovation** & **Practicality** &
\begin{tabular}{c} **Power Optimization** \\ **Method** \\ \end{tabular} & **Power Consumption** & **Power Comparison** \\ \hline
[122] & A flexible wireless sensor patch adopting BLE communication technology. & \
\begin{tabular}{c} Enable real-time wireless transmission and monitoring of heart rate. \\ \end{tabular} & Hardware & Below 3 mW &
\begin{tabular}{c} Compared with similar devices, its power consumption is reduced by approximately 40\%. \\ \end{tabular} \\ \hline
[126] & A Wi-Fi-based flexible wearable heart rate cloud monitoring module. & \
\begin{tabular}{c} Suitable for wireless transmission of heart rate \\ signals. \\ \end{tabular} & Hardware & N/A &
\begin{tabular}{c} Compared with traditional wired transmission and output, it consumes more than 25\%-less power. \\ \end{tabular} \\ \hline
[71] & A DCT-IV-based ECG compression algorithm is proposed. &
\begin{tabular}{c} Suitable for continuous \\ heart rate monitoring. \\ \end{tabular} & Algorithm & Below 5 mW & N/A \\ \hline
[139] & A dynamic feedback adaptive modulation (DF-AM) scheme is proposed. & \
\begin{tabular}{c} Suitable for low-power communication scenarios in the IoT. \\ \end{tabular} & Algorithm & 60 mW &
\begin{tabular}{c} Compared with traditional AM schemes, this scheme achieves more than 22\% \\ energy savings. \\ \end{tabular} \\ \hline
[62] & A heart rate monitoring system with wireless transmission functionality. & \
\begin{tabular}{c} Suitable for remote health \\ monitoring scenarios and supports long-term \\ \end{tabular} & Hardware-Algorithm co-design & 44.57 mW &
\begin{tabular}{c} Compared with similar devices, the power consumption is reduced by approximately 14.3\%. \\ \end{tabular} \\ \hline
[121] & A three-lead portable wireless transmission heart rate monitoring system is developed. &
\begin{tabular}{c} Suitable for remote heart \\ rate monitoring. \\ \end{tabular} & Hardware-Algorithm co-design & 72.6 mW & N/A \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Key references comparison of innovations, practicality, power consumption optimization methods, power consumption and power consumption comparison with other similar work of regarding heart rate signal transmission and output module in flexible Wearable Heart Rate Monitoring System. MQTT protocols; [PERSON] et al. 's ECG system integrates GFSK modulation with nRF24L01 transceivers and combines CRC check mechanisms to control retransmission power consumption within 5% of the total energy consumption. In the future, with the development of flexible electronics, the low-power design of heart rate signal transmission and output modules will evolve towards \"adaptive-intelligent-miniaturized\".
## 3 Results and Discussion
### Analysis of Variance (ANOVA)
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Source** & **Sum of Squares** & **df** & **Mean Squares** & **F-Value** & **_p-Value_ \\ \hline Model & \(2.7\times 10^{11}\) & 9 & \(3\times 10^{10}\) & 274.31 & \textless{}0.0001 \\ X\({}_{1}\) & \(2.52\times 10^{11}\) & 1 & \(2.52\times 10^{11
# The Objective Space and the Formulation of Design Requirement in Natural Laminar Flow Optimization
## 2 CFD Solver and Its Validation
### Design Variables in Geometry Description
The method is proposed against traditional variable screening that reduce dimensionality by simply removing variables; the latter often fails because there may be correlations between each variable in high-dimensional data [51]. PCA can solve that problem by providing new linear combinations of the original variables representing orthogonal eigenvectors of principal component axes in space, each of which with different variances [23; 24]. The first principal component is associated with the largest variance, and the following ones are perpendicular to the previous ones [52]. In some aerodynamic designs, the application of PCA is mainly on the data processing, e.g., classifier. Some examples can be seen in reduced-order models for simulations balancing computation cost and flowfield accuracy in numerous fields [53; 54; 22; 55; 56]. The data-oriented technique has been studied to accelerate the process of capturing the dominant modes of a system [57]. This type of PCA applications is focused on the idea that if samples of similar features are clustered, then the methods can be applied to them more effectively. Beyond that, PCA is not often applied to extract useful information linked with objective space. One similar example is found in [58] where PCA is used to guide the application of evolution operators in Genetic Algorithm where the front of non-dominated solutions is divided into sub-fronts. Its information was obtained from the calculated aerodynamic performance distribution; then, the result was fed back to the design space to further manipulate the samples. This guidance from objective space is no longer simply an aerodynamic performance progress of individual samples as in many traditional genetic algorithm; on the contrary, the extracted global information of objective space alleviates the dependence of randomness in the design space, which brings benefits to their study. In such spirit, this paper is also focused on studying objective space information by PCA via the formulation of design requirement, which constitutes the novelty of this paper.
## 1 Introduction
However, this design introduces significant leakage power and poor read stability despite enhanced write capabilities. In summary, these cell designs tend to offer only partial SEU protection with insufficient focus on SEMNU effects. They grapple with issues such as compromised read/write stability and high leakage power. Achieving stable memory operation is essential for overall system performance, particularly in space environments where power efficiency critically affects system longevity [1,10]. This paper proposes RSP16T, which can recover its original state even after all sensitive nodes have been flipped by a significant level of SEUs. Additionally, this structure exhibits strong resilience to SEMNUs at the storage node pair (Q-QB). This paper is divided into the following sections. Section 2 explains the basic operation and provides an analysis of SEU recovery for the proposed cell. Section 3 presents simulation setups and comparative studies of RSP16T and other soft error immune SRAM cells. Finally, Section 4 concludes the paper.
# Fine-Scale Population Estimation Based on Building Classifications: A Case Study in Wuhan
## 2 Materials and Methods
### Population Estimation at Fine-Scale  
Living spaces are the actual centers of human distributions in geographical space, which has a low correlation with non-residential buildings, such as commercial service buildings and public service buildings. Based on the building classifications, this paper screens out residential houses and counts characteristic variables, such as the perimeter, area, and total number of floors of subdistrict residential buildings. To verify the validity of variables, the random forest method is applied for variable screening and correlation analysis. Since it has clear advantages when dealing with unbalanced data. A linear model is established with a multiple regression method, according to the number of buildings, geometric features, and population in an administrative division (Figure 4).
## 3 Results
### Plate Stiffness  
As shown in Figure 4, the stiffness of the plates varied with thickness and curvature radius. For the 1 mm thick plate, when the curvature radius increased from 200 mm to 250 mm, the stiffness increased by 4.57%. However, further increasing the radius to 300 mm resulted in a 3.27% decrease in stiffness. For the 1.5 mm thick plate, the stiffness increased by 4.13% when the curvature radius was changed from 200 mm to 250 mm, and further increased by 1.33% when the radius was increased from 250 mm to 300 mm. The 2 mm thick plate showed an increase in stiffness of 4.37% from 200 mm to 250 mm and 3.44% from 250 mm to 300 mm.  
Regarding changes in plate thickness, for a curvature radius of 200 mm, increasing the plate thickness from 1 mm to 1.5 mm resulted in a significant stiffness increase of 147.78%, and further increasing the thickness from 1.5 mm to 2 mm raised the stiffness by 99.27%. For a curvature radius of 250 mm, the increase in thickness from 1 mm to 1.5 mm led to a 141.76% increase in stiffness, and from 1.5 mm to 2 mm, the stiffness increased by 99.73%. For a curvature radius of 300 mm, the thickness increase from 1 mm to 1.5 mm resulted in a 153.25% increase in stiffness, and the increase from 1.5 mm to 2 mm resulted in a 103.88% increase.  
Figure 3: (a) Scatter plot and fitted line graph (R\({}^{2}\) > 0.99) of results from ten tests at loading rates of 7.5 mm/s, 10 mm/s, 12.5 mm/s, and 15 mm/s, within displacement range of 80–90%. (b) Scatter plot and fitted line graph (R\({}^{2}\) > 0.99) of simulation results at loading rates of 7.5 mm/s, 10 mm/s, 12.5 mm/s, and 15 mm/s, within displacement range of 80–90%. (c) Box plot of stiffness values within displacement range of 80–90% for ten tests at each rate, showing maximum, minimum, median, outliers, upper quartile, and lower quartile, along with mean value and standard deviation. “n.s. (\(p\) = 0.114)” indicates no significant difference between groups of stiffness data. (d) Error percentage between simulated and experimental results compared to measured stiffness at each rate.
## 5 Integration of Pruning for Stream-Lined Control
### Pruning Methods with Periodic PSO-H Retraining
In almost all cost functions and for all earthquakes, the pruned matrix outperformed the full-state matrix and was closer to the performance of the LQR controller. Similar to the full-state controller, the pruned control scheme is not as adaptable to the Kobe and Loma Prieta earthquakes. However, across all earthquakes, this controller scheme places more demand on the actuators, which likely contributes to its increase in control effectiveness. The pruned matrix showed the most promise, though, in addressing the communication challenges of the network. For the El Centro earthquake, the pruned method transmitted 19.4% less data than the LQR and for the Kobe, it transmitted 47.5% less data. The two methods transmitted equal amounts of data for the Loma Prieta earthquake.
## 4 Correlation Analysis
### Oxford Government Responses and Citizens' Mobility Features
#### 4.1.2 Citizens' Mobility Features--New Confirmed Cases  
The analysis presents the following findings from the correlation analyses involving mobility features and new confirmed cases (Appendix C, table (a)):  
* The correlations exhibit high levels, with the global score for the residential feature reaching 7.991, and often being lower than zero. Notably, the global score for the retail and recreation feature stands at \(-\)6.796, with a peak in the first wave for the UK.
* The residential feature correlation is predominantly positive for each country and all three time periods, except for France in the third wave (\(-\)0.136), suggesting a divergent governmental strategy.
* Traffic data also demonstrate high levels of negative correlations.  
The continuous new deceased feature correlation levels closely approach 1 (peaking at 0.914 for the UK in the first wave), signifying a notable correlation between new deaths and new confirmed cases, particularly in the first and second waves (with a global score of 4.015 in the first and 3.579 in the second). This correlation notably decreases from the first to the third wave (global score 1.688).
# New and Efficient Algorithms for Producing Frequent Itemsets with the Map-Reduce Framework
## 2 Background and Related Work
### Association Rules and Frequent Itemsets  
Association rule mining was introduced in [5; 6] as a market basket analysis for finding items that were bought together--if a customer bought item(s) X, then with high probability item(s) Y will be also purchased (X \(\Longrightarrow\) Y) (e.g., 98% of customers who purchase tires and auto accessories also get an automotive service done). A pre-requisite to finding association rules is the mining of frequent itemsets (FIM) (itemsets that appear in at least some percentage of the transactions).  
One of the most well-known algorithms for association rules is the Apriori algorithm described in [5; 6]. This algorithm uses a pruning rule called Apriori, which states that an itemset may be frequent if all its subsets are also frequent. The algorithm is based on iteratively generating candidates for frequent itemsets and then pruning them. The algorithm starts with candidates of size one, which includes all possible items, and every iteration increases the length of the candidates by one. At the end of each iteration, the candidates are pruned by their count in the DB and those who survive (their count is larger than the minimal threshold) are added to the final set of frequent itemsets. Candidates for the next iteration are being generated based on the survivors. The algorithm stops when it cannot generate longer candidates, and then it generates all association rules from the frequent itemsets.  
There are several versions of implementing Apriori in the distributed environment [20; 21]. The most important idea is that if an itemset is frequent in a union of distributed databases, it must be frequent in at least one of them. A simple proof by contradiction goes like this:  
Assume that itemset \(x\) is frequent in union DB (\(\mathcal{D}=\cup\mathcal{D}_{1}\)), then \(sup_{\mathcal{D}}(x)\) (count of \(x\) in the \(\mathcal{D}\)) is at least \(minSup*|\mathcal{D}|\) times. Assume also that \(x\) is not frequent in any partial \(\mathcal{D}_{1}\), then:  
\[sup_{\mathcal{D}_{i}}(x)<minSup*|\mathcal{D}_{i}|.\]  
Then:  
\[sup_{\mathcal{D}}(x)=\sum sup_{\mathcal{D}_{i}}(x)<\sum minSup*|\mathcal{D}_{ i}|=minSup*\sum|\mathcal{D}_{i}|=minSup*|\mathcal{D}|\]  
and we get a contradiction of \(x\) being frequent in the \(\mathcal{D}\).  
A similar idea will be used by us in the incremental case.