esa-sceva/satcom-chunk-collection huggingface dataset:
## 4 Security Definition and Problem Statement
### Secure Dot Product Based on Homomorphic Encryption  
Homomorphic encryption is a probabilistic public key encryption [9; 32]. Let \(HE_{pk}(x)\) and \(HD_{pr}(y)\) be the encryption and decryption functions in this system with public key \(pk\) and private key \(pr\). Without private key \(pr\), no adversary can guess the plaintext \(x\) in polynomial time. Furthermore, \(HE_{pk}(x)\) has a semantic security [33] property, which means no adversary can compute any function of the plaintext from the ciphertext set. Interestingly, the full homomorphic encryption has two amazing properties, namely: additive and multiplicative. Additive property allows adding two encrypted numbers, i.e., \(HE_{pk}(x1)\times HE_{pk}(x2)=HE_{pk}(x1+x2)\). Given a constant \(c\) and a ciphertext \(HE_{pk}(x)\), the multiplicative property works as follows: \(HE_{pk}(x)^{c}=HE_{pk}(c\times x)\). In this paper, we adopt [PERSON]'s system [34] for the practical implementation because of its efficiency.  
Let \(u\) and \(v\) be secure vectors of _[PERSON]_ and _[PERSON]_, respectively. _Both_ vectors are of the same size \(n\). Below, we show how homomorphic encryption can be used to compute the secure dot product between \(u\) and \(v\). At the beginning, _[PERSON]_ encrypts her private vector component-wise, i.e., \(z_{i}\gets HE_{pk}(u_{i})\), and sends the encrypted vector \(z\) to _[PERSON]_. Upon receiving \(z\), _[PERSON]_ computes the encrypted component-wise product between \(z\) and \(v\) based on the multiplicative property, (i.e., \(y_{i}=z_{i}^{vi}\), _for all_\(i=1,...,n\)). He then sums up these products based on the additive homomorphic property to compute the encrypted dot product \(EDot\) such as: \(EDot=y_{1}+y_{2}+...+y_{n}\). After receiving \(EDot\) from _[PERSON]_, _[PERSON]_ uses her private key \(pr\) to decrypt it and to obtain the plaintext value of \(u\times v\), i.e., \(HD_{pr}(EDot)=u\times v\). Note that _[PERSON]'s_ private vector \(u\) is not revealed to _[PERSON]_ because only encrypted values of \(u\) are sent to _[PERSON]_. Therefore, without prior knowledge of _[PERSON]'s_ private key, neither \(u\) vector nor matching plaintext can be recovered by semi-trusted _[PERSON]_ or any adversary. Thus, this method meets the requirement of second scenario as explained in Section 1 with respect to privacy-preserving.
###### Abstract
In these experiments, the number of received packets at the gateway and the receive signal strength indicator (RSSI) were measured while modifying the transmission distance, the number of devices used, and the main LoRa transmission parameters. SF was varied from 7 to 12; BW was set to either 125 kHz, 250 kHz, or 500 kHz; CR values of 4/5, 4/6, 4/7 and 4/8 were used. The technical novelty of our research can be identified in the following aspects: (a) the characteristics of the experiments performed to evaluate LoRa are different from those executed in the related works; (b) the prototype proposed for the monitoring system is based on an ITS architecture that was designed considering internationally recognized references; and (c) the analysis of the results of the experiments, with the help of comparati ve graphs and tables, to facilitate reading and understanding for the user. The remainder of this paper is organized as follows: Section 2 presents the related works; Section 3 presents the materials and methods used in the project, including the description of the performed LoRa evaluation experiments; Section 4 presents the experimental results; Section 5 discusses the results, and Section 6 presents the conclusions of the study.
###### Abstract  
A study of spatiotemporal variability and synchronization effects in continuous seismic records (seismic noise) on a network of 21 broadband seismic stations on the Kamchatka Peninsula was carried out in connection with the occurrence of strong earthquakes, \(M=7.2\)-\(8.3\). Data of 1-min registrations of the vertical movements velocity Earth's surface were used for constructing time series of daily values of the generalized Hurst exponent \(\alpha^{*}\), singularity spectrum support width \(\Delta\alpha\), wavelet-based spectral exponent \(\beta\), and minimum normalized entropy of squared orthogonal wavelet coefficients \(Ent\) for all stations during the observation period 2011-2021. Averaged maps and time-frequency diagrams of the spectral measure of four noise parameters' coherent behavior were constructed using data from the entire network of stations and by groups of stations taking into account network configuration, volcanic activity and coastal sea waves. Based on the distribution maps of noise parameters, it was found that strong earthquakes arose near extensive areas of the minimum values of \(\alpha^{*}\), \(\Delta\alpha\), \(\beta\), and the \(En\) maximum values advance manifestation during several years. The time-frequency diagrams revealed increased amplitudes of the spectral measure of the coherent behavior of the 4-dimensional time series (synchronization effects) before three earthquakes with \(M_{w}=7.5\)-\(8.3\) over months to about one year according to observations from the entire network of stations, as well as according to data obtained at groups of continental and non-volcanic stations. A less-pronounced manifestation of coherence effects diagrams plotted from data obtained at coastal and volcanic groups of stations and is apparently associated with the noisiness in seismic records caused by coastal waves and signals of modern volcanic activity. The considered synchronization effects correspond to the author's conceptual model of seismic noise behavior in preparation of strong earthquakes and data from other regions and can also be useful for medium-term estimates of the place and time of seismic events with \(M_{w}\geq 7.5\) in the Kamchatka.  
seismic noise; time series; singularity spectrum; wavelet analysis; spectral measure of coherence; Kamchatka Peninsula; earthquake prediction
# Laser-Assisted Etching of EagleXG Glass by Irradiation at Low Pulse-Repetition Rate
## 3 Experimental Results
### Morphology of the Etched Structures
After longer etching times, the whole track results excavated, an elliptical cone inlet is formed and the initial inhomogeneity in the cross-section is no longer discernible. Figure 5: Examples of etched cones (top-view microscope pictures), obtained from tracks irradiated with orthogonal polarisation at two different inscription pulse-energies (\(E_{p}=2.2\)\(\upmu\)J and \(E_{p}=8.6\)\(\upmu\)J), \(v_{t}=1\) mm/s and 25 kHz repetition-rate. Etching was performed in HF solution for 10 min or in KOH for 6 h. Scalebars correspond to 50 \(\upmu\)m.  
Figure 6: Microscope pictures of the cross-section of the irradiated tracks prior to etching (leftmost images), and after a different time of immersion in etching baths of HF or KOH. Red arrows point to the dark dots in the cross-section of the track, which corresponds to the point of maximum etching sensitivity. The two rows of images regard tracks written with two different values of \(E_{p}\), \(v_{t}=1\) mm/s and 25 kHz repetition rate. The length of the scalebars is 5 \(\upmu\)m.  
We note that a very similar behaviour, with the etching starting from a point-like feature in the cross-section modified track, was observed in our previous work [23] on the same glass EagleXG, despite the very different irradiation conditions. In particular, the point-like feature which yields enhanced etching rates corresponds to a small dark dot in the cross-section, visible with the optical microscope, which was identified as the location of the focal spot during irradiation [14]. Further investigations on the nature of this dark dot would be needed to fully explain the laser-assisted etching dynamics in this material. In any case, the interpretation of the black dot as a micro-crack propagating uniformly for the whole track length [23] seems compatible with the experimental findings of the increased surface roughness at high pulse energy (Figure 5). In fact, as the irradiation laser fluence increases, the modification undergone by the material may possibly become more and more disruptive and irregular. The present results confirm substantial differences in the etching process occurring in EagleXG glass with respect to the case of pure fused silica. In fused silica, the whole cross-section of the laser-modified track is uniformly etched. Moreover, birefringent nanogratings, whose orientation depends on the polarisation direction of the inscribing laser, are observed in fused silica. These are deemed responsible for the polarisation dependency of the etching rates. In the experiments here described on EagleXG, we note that the etching process starts from a point-like structure formed in the focal spot of the writing laser, and it extends to the remaining track cross-section only for longer times. We also observed some polarisation dependency, but nanogratings were not noticeable. Further investigation on the morphology of the irradiated track at the microscopic level is needed to fully understand its complex etching behaviour.
## 2 Related Work  
### Sentence-Level Event Extraction (SEE)  
The existing approaches for SEE can be broadly categorized into pattern-based and statistical learning methods. Pattern-based methods involve mining contextual argument association features for different event types and designing corresponding pattern-matching templates. However, these methods need better transferability and require extensive manual operations. On the other hand, statistical learning methods focus on extracting appropriate sentence features and selecting suitable classifiers for event type detection and argument extraction. Initially, these methods heavily relied on manually engineered features. With advancements in deep learning techniques, researchers began leveraging the feature representation capabilities of deep neural networks to extract text features automatically. [PERSON] et al. (2017) creatively proposed a dynamic multi-pooling convolutional neural network, which divides sentences into segments and applies different convolution pooling operations to each part, augmented by distance encoding for event extraction. [PERSON] et al. (2018) simultaneously extracted multiple events from sentences by combining graph structures with attention mechanisms. [PERSON] et al. (2019) introduced imitation learning in event extraction, enhancing the learning effectiveness of infrequent but important events through reward allocation mechanisms.  
Furthermore, some researchers have leveraged syntactic features to extract events. [PERSON] et al. (2019) introduced syntactic dependency relations in the network input and utilized memory matrix encoding to capture relationships between trigger words and arguments. Similarly, [PERSON] et al. (2018) incorporated syntactic dependencies into the RNN network. With the advancement of pre-trained language models, researchers have begun exploring the application of BERT in event extraction tasks. [PERSON] et al. (2019) enhanced the semantic representation capabilities of their event extraction model by incorporating BERT during the text input stage. In the SEE task, the same word can represent different events in different contexts, requiring accurate classification and attribution based on the context. Therefore, integrating more semantic and contextual features is necessary to improve the extraction of scattered arguments and multiple event information in the future.
## 7 Discussion
### Comparison with Other Demagnetization Methods  
In this paper, the commonly used AC demagnetization method is adopted to test the toroidal transformer. Below are the demagnetization data of this paper, and the excitation inductance of the toroidal transformer is used to judge the demagnetization result.  
First, a DC current of 5 A is applied to the toroidal transformer for 10 s to ensure that the transformer reaches magnetic saturation. The excitation inductance value at this time is used as the starting point. The signal generator outputs a demagnetization signal with a frequency of 0.1 Hz per cycle and a duration of 1 min. The threshold value for the end of demagnetization is determined through multiple cycles, and the measurement results are shown in the Table 8 below.  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Demagnetization Cycle** & **Measured Inductance Value (mH)** \\ \hline
0 & 7.8 \\
1 & 14.5 \\
2 & 18.9 \\
3 & 20.7 \\
4 & 22.8 \\
5 & 23.4 \\ \hline \hline \end{tabular}
\end{table}
Table 8: Excitation inductance data during multiple demagnetization rounds.  
According to multiple measurements, when the excitation inductance of the transformer tends to 23.4 mH, it will gradually remain almost unchanged, which can be regarded as the end of demagnetization. It can be seen that the traditional AC demagnetization method often takes minutes, which is much longer than the method used in this paper.
###### Abstract  
Heat stress in particular can damage physiological processes, adaptation, cellular homeostasis, and yield of higher plants. Early detection of heat stress in leafy crops is critical for preventing extensive loss of crop productivity for global food security. Thus, this study aimed to evaluate the potential of a snapshot-based visible-near infrared multispectral imaging system for detecting the early stage of heat injury during the growth of Chinese cabbage. Two classification models based on partial least squares-discriminant analysis (PLS-DA) and least-squares support vector machine (LS-SVM) were developed to identify heat stress. Various vegetation indices (VIs), including the normalized difference vegetation index (NDVI), red-edge ratio (\(\text{RE}/\text{R}\)), and photochemical reflectance index (PRI), which are closely related to plant heat stress, were acquired from sample images, and their values were compared with the developed models for the evaluation of their discriminant performance of developed models. The highest classification accuracies for LS-SVM, PLS-DA, NDVI, \(\text{RE}/\text{R}\), and PRI were 93.6%, 92.4%, 72.5%, 69.6%, and 58.1%, respectively, without false-positive errors. Among these methods for identifying plant heat stress, the developed LS-SVM and PLS-DA models showed more reliable discriminant performance than the traditional VIs. This clearly demonstrates that the developed models are much more effective and efficient predictive tools for detecting heat stress in Chinese cabbage in the early stages compared to conventional methods. The developed technique shows promise as an accurate and cost-effective screening tool for rapid identification of heat stress in Chinese cabbage.  
nodestructive evaluation; Chinese cabbage; snapshot multispectral imaging: heat stress; visible-near infrared +
Footnote †: journal: Medical Imaging  
1
# Energy Efficient Clustering Protocol for FANETS Using Moth Flame Optimization
## 2 Background and Motivation
### What Links Make FANETs, Different from MANETs, and VANETs?  
The IEEE 802.11a network technology is today's essential network technology for constructing FANETs. Mesh ad hoc networks utilize the 802.11s wireless networking standard [14]. When two UAVs interact, this is called Single Hop Communication. Alternatively, a Multi-Hop Communication channel may be created across the other UAVs in UAV-to-UAV communication, as seen in Figure 3.  
Fixed infrastructure, such as a satellite or a ground station, is used in the case of FANETS-to-FANETS Communication, in which UAVs connect with improved infrastructure. FANET may be a more advanced version of MANET and VANET [15]. However, there are several distinctions between FANET and the existing ad hoc networks, including the following: FANET nodes have far greater mobility than MANET or VANET nodes. FANET nodes fly in the air, in contrast to the traditional MANET and VANET nodes, representing walking men and vehicles.  
1. Due to the high mobility of FANET nodes, the network's topology changes more frequently than the network itself [16; 19; 23]. A typical MANET or VANET network topology is shown in Figure 4.
2. There are now many ad hoc networks striving to connect. For example, Wireless sensor networks make extensive use of these technologies for gathering and transmitting data about the surrounding environment [24]. Peer-to-peer and broadcast traffic must be allowed simultaneously for FANET to work effectively.
3. The Distances between FANET and FANETS nodes are much longer than the distances between the two networks [12; 13; 24]. Unmanned aerial vehicles (UAVs) need a more extended communication range than either MANETs or VANETs if they are to be linked together. Consequently, radio links, hardware circuits, and physical layer behaviour are all impacted.  
Figure 4: MANETS and VANETS network structure.  
Figure 3: Types of FANETs network.  
Multi-UAV systems may contain various types of sensors, each of which may need a separate data transmission strategy [19].
# A Novel Active Polyphase Filter Employing Frequency-Dependent Image Rejection Enhancement Technique
## 1 Introduction
Although active polyphase filters (APPFs) are also negatively affected by PVT variations, APPFs have the general advantages of high signal gain, compact size, and easy tuning compared to passive schemes [24]. However, unavoidable non-ideal factors such as device parasitic parameters and layout asymmetry can lead to severe gain and phase imbalances, which degrade the IRR at high frequencies. To improve the operating frequency of the APPF, the negative effect of the secondary pole on the rejected frequency is mitigated by optimizing the parasitic capacitance of the key node. In addition, the overall layout of the APPF is made more symmetrical to reduce quadrature imbalance. Unfortunately, since parasitic capacitance cannot be eliminated, the conventional APPF optimization scheme becomes less effective or even completely ineffective as the operating frequency further increases. In this paper, a novel APPF is proposed employing the frequency-dependent image rejection enhancement technique based on secondary pole compensation in the 180 nm CMOS process. Unlike conventional schemes, the operating frequency of the proposed APPF is no longer limited to the secondary pole frequency. Through the analysis of the theoretical model, it is proved that the proposed enhancement technique can fundamentally remove the negative effect of the secondary pole on image rejection. Meanwhile, because the proposed APPF is tunable, great IRRs still can be achieved when the quadrature input signals have phase imbalances, as well as when there are PVT variations. The simulation results show that the proposed image rejection enhancement technique improves the IRR by more than 30 dB in the single-stage circuit at the operating frequency of 100-300 MHz. In addition, the proposed APPF can be cascaded in multiple stages to achieve a better IRR and wider bandwidth, and each stage can be tuned independently to achieve optimal overall performance. The simulation result of the two-stage APPF shows the above conclusion. The measured IRR of \(-\)31 dB over the 95-105 MHz frequency band confirms that the proposed enhancement technique is suitable for improving the performance of APPFs at high operating frequencies. The remaining sections of this paper are organized as follows: Section 2 presents the theoretical model of the APPF and the proposed image rejection enhancement technique; the circuit implementations of the proposed APPF are presented in Section 3; the simulation and measurement results are presented in Section 4; Section 5 compares the simulation and measurement results and analyzes the possible reasons for the discrepancies; and finally, the conclusions are drawn in Section 6.
## 4 Empirical Insights from Sectorial and Regional Studies
### AI Synergies and Revenue Growth in European SMEs
#### 4.2.1 AI Adoption in European SMEs and the Role of Internal Capabilities [27]  
[PERSON] et al. (2024) [27] conducted an empirical analysis involving 12,108 SMEs across the European Union, utilizing data from the Flash Eurobarometer and advanced analytics techniques (regression, ANN, tree regression). Their findings underscore that internal capabilities--particularly digital and innovation capabilities--are far more influential for AI adoption than external environmental support alone. Quantitative indicators show that digital capabilities (e.g., use of IoT, cloud, robotics) exhibit a significantly stronger correlation with AI integration outcomes than business environment factors. For example, SMEs with high digital capability scores had up to a 52% higher likelihood of successful AI adoption. Innovation capabilities also showed a positive impact, especially when digital maturity was moderate, revealing synergistic effects.  
In contrast, environmental support variables (such as access to funding or skilled labor) had a weaker and less consistent influence, reinforcing the need to emphasize internal readiness and complementary innovation processes. This aligns with the technological and organizational dimensions of the TOE framework and emphasizes the DOI principle of innovation compatibility. The study validates the importance of customized interventions that focus on strengthening SME-specific digital and innovative capabilities while designing ecosystem support to complement, rather than replace, internal drivers.
Sensors_**2009**, \(9\), 5844-5877; doi:10.3390/s90705844  
**SUPA-ICGRESS**  
_Sensors_  
**ISSN 1424-8220**  
www.mdpi.com/journal/sensors  
_Article_  
**LoWMob: Intra-PAN Mobility Support Schemes for 6 LoWPAN**  
**[PERSON] 1,*, [PERSON] 2, [PERSON] 1 and [PERSON] 1**  
* 1 Information and Communication Department/Ajou University, South Korea; E-Mails: [EMAIL_ADDRESS] (K.-H.K.); [EMAIL_ADDRESS] (S.-W.Y.)
* 2 USN Networking Research Team / Electronics and Telecommunications Research Institute (ETRI), Korea; E-Mail: [EMAIL_ADDRESS]
* 4 Author to whom correspondence should be addressed; E-Mail: [EMAIL_ADDRESS]; Tel.: +82-31-219-1898; Fax: +82-31-2191607  
_Received: 22 May 2009; in revised form: 23 June 2009 / Accepted: 25 June 2009 / Published: 23 July 2009_  
**Abstract:** Mobility in 6 LoWPAN (IPv6 over Low Power Personal Area Networks) is being utilized in realizing many applications where sensor nodes, while moving, sense and transmit the gathered data to a monitoring server. By employing IEEE802.15.4 as a baseline for the link layer technology, 6 LoWPAN implies low data rate and low power consumption with periodic sleep and wakeups for sensor nodes, without requiring them to incorporate complex hardware. Also enabling sensor nodes with IPv6 ensures that the sensor data can be accessed anytime and anywhere from the world. Several existing mobility-related schemes like HMIPv6, MIPv6, HAWAII, and Cellular IP require active participation of mobile nodes in the mobility signaling, thus leading to the mobility-related changes in the protocol stack of mobile nodes. In this paper, we present LoWMob, which is a network-based mobility scheme for mobile 6 LoWPAN nodes in which the mobility of 6 LoWPAN nodes is handled at the network-side. LoWMob ensures multi-hop communication between gateways and mobile nodes with the help of the static nodes within a 6 LoWPAN. In order to reduce the signaling overhead of static nodes for supporting mobile nodes, LoWMob proposes a mobility support packet format at the adaptation layer of 6 LoWPAN. Also we present a distributed version of LoWMob, named as DLoWMob (or Distributed LoWMob), which employs Mobility Support Points (MSPs) to distribute the traffic concentration at the gateways and to optimize the multi-hop routing path between source and destination nodes in a 6 LoWPAN. Moreover, we have also discussed the security considerations for our proposed mobility schemes. The performance of our proposed schemes is evaluated in terms of mobility signaling costs, end-to-end delay, and packet success ratio.  
Keywords:sensor networks; 6 LoWPAN; network-based mobility support +
Footnote †: journal: Journal of the Royal Society Interface