esa-sceva/satcom-chunk-collection huggingface dataset:
## 3 Measurement Setup
### Tidal Turbine Gearbox Test Rig  
The test rig used for these measurements has been developed by TWI Ltd. in the UK and the University of Brunel in an effort to replicate a geared tidal turbine with the ability to be submerged into the water. The test rig consists of a 3-phase 750 Watt AC motor controlled by a Variable Frequency Driver (VFD) capable of running at 1500 rpm, a 3-stage spur and helical parallel gearbox with a ratio of approximately 1:69 and 3 blades at the main shaft turning at approximately 22 rpm. The tidal turbine gearbox test rig setup is shown in Figure 3.  
This test rig is instrumented with two accelerometers in X and Y directions mounted on the input shaft of the gearbox (i.e., slow speed shaft) over the bearing to record vibration data of the gear box. The sensors used are AC 150-2C accelerometer by Connection Technology Centre Inc with a nominal range of 1 Hz to 10 kHz.
## 2 CST Studio Suite Software Simulations
### Source of High Frequency EMF  
As a source of high frequency EMF for the simulations in this work, we used a Planar Inverted-F Antenna (PIFA), whose shape resembles an inverted letter F. It is a popular choice for portable wireless devices due to its small size, low price, and many other features [21; 22; 23]. It is often used in mobile technology, mainly in the Digital Cellular System (DCS) 1800 MHz band, used for GSM and LTE mobile networks. The frequency range usually includes 1710-1880 MHz, where 1710-1785 MHz represents the uplink (transmission from the mobile device to the base station) and 1805-1880 MHz for the downlink (transmission from the base station to the mobile device) [24]. These portable PIFA devices have dual polarization, which gives them the advantage of placing the antenna in any position. The structure consists of a ground plate, a patch, a dielectric, a shorting wall, and a feeding point. The patch is made of copper and is placed on a thin dielectric substrate that is installed above the ground plate. The PIFA antenna is powered by a coaxial cable and uses the inner wire of the coaxial connector, which is extended through the dielectric and attached to the radiating area. The outer shield cover is connected to the conductive plate (Figure 1). This power supply method has low parasitic radiation and is easy to implement [25; 26].  
PIFA antennas can be easily tuned by changing the length and position of the vertical element, which allows for precise adaptation of the antenna to the desired frequency band. The created single-band PIFA antenna works at a frequency of 1800 MHz, while parameter S11 represents the return loss of the device, which in our case for 1800 MHz is around \(-17\)dB, as can be seen in the Figure 2. The S11 parameter represents the energy reflected from the antenna and is therefore known as the reflection coefficient or return loss [27].
## 3 Results
### Spatial Patterns of NEP Estimates  
From 2003 to 2021, the total annual average NEP over China was 489.67 \(\pm\) 38.27 Tg C/yr (mean \(\pm\) standard error), with an average of 68.78 g C/m\({}^{2}\)/yr per unit area (Figure 4a,b). Of the pixels, 52.0% showed a multiyear average NEP greater than 0, serving as carbon sinks (Figure 4c). Spatially, stronger carbon sink capabilities were observed in the southeast, southwest, and the three northeastern provinces, generally exceeding 300 g C/m\({}^{2}\)/yr, while most of the Bohai Sea Rim area, Inner Mongolia, and the central region of the Qinghai-Tibet Plateau exhibited weak carbon sources (Figure 4a).  
Across diverse vegetation types, the multiyear average NEP of EBF (600.53 g C/m\({}^{2}\)/yr) was significantly higher than that of other vegetation types, followed by DBF (348.64 g C/m\({}^{2}\)/yr) and SAV (236.48 g C/m\({}^{2}\)/yr) (Figure 4d). In contrast, SHB, GRA, and CRO functioned as carbon sources, displaying negative multiyear average NEP values of \(-\)113.34, \(-\)46.16, and \(-\)45.43 g C/m\({}^{2}\)/yr, respectively. From a regional perspective, all four economic regions in China played a role as carbon sinks from 2003 to 2021 (Figure 4e). The multiyear average NEP in the eastern region (174.17 g C/m\({}^{2}\)/yr) was the greatest, likely due to the highest forest coverage in China, followed by the northeastern, central, and western regions, with NEP values of 119.52, 101.59, and 32.49 g C/m\({}^{2}\)/yr, respectively.
## 3 Method
### Authentication and Issuing Invoice Phase  
#### 3.5.1 Case 1: Direct Authorization  
After reviewing the Licensee's identity, the Content Administrator generates a transaction ID and invoice to the Licensee. We present the flowchart of the authentication and issuing an invoice phase for direct authorization in Figure 6.  
* Step 1: The Licensee generates a random value \(k_{L-M}\), calculates: \[z_{L-M}=h(ID_{L},M_{L-M},Cert_{L},TS_{L-M},ID_{BC}),\] (2) \[(x_{L-M},y_{L-M})=k_{L-M}G,\] (3) \[r_{L-M}=x_{L-M}\text{mod}n,\] (4) \[s_{L-M}=k_{L-M}{}^{-1}(z_{L-M}+r_{L-M}d_{L})\text{mod}n,\] (5) \[Enc_{L-M}=Ep_{PK_{M}}(ID_{L},M_{L-M},Cert_{L},TS_{L-M},ID_{BC}),\] (6) and sends \(ID_{L},Enc_{L-M},(r_{L-M},s_{L-M})\) to the content administrator. The \(ID_{L}\) is encrypted to check integrity. The second \(ID_{L}\) is to show the Licensee's identity to the content administrator. * Step 2: The Content Administrator first calculates: \[(ID_{L},M_{L-M},Cert_{L},TS_{L-M},ID_{BC})=D_{SK_{M}}(Enc_{L-M}),\] (7) uses \[TS_{NOW}-TS_{L-M}\leq\Delta T\] (8) to confirm whether the timestamp is valid, verifies \(Cert_{L}\) with \(PK_{L}\), verifies the correctness of the ECDSA signature, then calculates: \[z_{L-M}{}^{\prime}=h(ID_{L},M_{L-M},Cert_{L},TS_{L-M},ID_{BC}),\] (9) \[u_{L-M1}=z_{L-M}{}^{\prime}s_{L-M}{}^{-1}\text{mod}n,\] (10) \[z_{L-M}=h(ID_{L},M_{L-M},Cert_{L},TS_{L-M},ID_{BC}),\]0 (11) \[z_{L-M}=h(ID_{L},M_{L-M},Cert_{L},TS_{L-M},ID_{BC}),\]1 (12) \[z_{L-M}=h(ID_{L},M_{L-M},Cert_{L},TS_{L-M},ID_{BC}),\]2  
\((ID_{BC},BC_{L-M})\) will also be uploaded to the blockchain center. Then the CA generates a random value \(k_{M-L}\) and calculates:  
\[z_{L-M}=h(ID_{L},M_{L-M},Cert_{L},TS_{L-M},ID_{BC}),\]3  
\[z_{L-M}=h(ID_{L},M_{L-M},Cert_{L},TS_{L-M},ID_{BC}),\]4  
\[z_{L-M}=h(ID_{L},M_{L-M},Cert_{L},TS_{L-M},ID_{BC}),\]5  
\[z_{L-M}=h(ID_{L},M_{L-M},Cert_{L},TS_{L-M},ID_{BC}),\]6  
\[z_{L-M}=h(ID_{L},M_{L-M},Cert_{L},TS_{L-M},ID_{BC}),\]7  
and sends \(ID_{M},Enc_{M-L},(r_{M-L},s_{M-L})\) to the Licensee. * Step 3: The Licensee first calculates:  
\[z_{L-M}=h(ID_{L},M_{L-M},Cert_{L},TS_{L-M},ID_{BC}),\]8  
uses  
\[z_{L-M}=h(ID_{L},M_{L-M},Cert_{L},TS_{L-M},ID_{BC}),\]9  
to confirm whether the timestamp is valid, verifies the correctness of the ECDSA signature, then calculates:  
\[(x_{L-M},y_{L-M})=k_{L-M}G,\]0  
\[(x_{L-M},y_{L-M})=k_{L-M}G,\]1  
\[(x_{L-M},y_{L-M})=k_{L-M}G,\]2  
\[(x_{L-M},y_{L-M})=k_{L-M}G,\]3  
\[(x_{L-M},y_{L-M})=k_{L-M}G,\]4  
If the verification is passed, the content request information is confirmed by CA, and the smart contracts mlins and mlchk will be sent. The content is as follows (Scheme 4):The Licensee calculates:  
\[(x_{L-M},y_{L-M})=k_{L-M}G,\]5  
\((ID_{BC},BC_{M-L})\) will also be uploaded to the blockchain center.
# Advanced Scheme to Generate MHz, Fully Coherent FEL Pulses at nm Wavelength
## 2 Overview of Methods  
### Employing an Oscillator in Standard Seeding Schemes  
In this section, we review different schemes that can be implemented with an oscillator in order to provide high repetition rate seed pulses. In standard seeding techniques, an external seed laser is used to modulate the energy of the electron beam as a result of their interaction along an undulator (modulator). In this case, one seed laser pulse needs to be injected for each electron bunch. The purpose of adding an optical cavity to a seeding scheme is to replace the need for an external seed laser, because the cavity can recirculate a radiation pulse and maintain its peak power and pulse properties. In this case, in addition to the energy modulation process which happens along the modulator, an amplification process must also occur. This is important because the power gain is used to compensate for unavoidable cavity losses. Here, we define as net gain the difference between the peak power at the beginning of a pass n + 1 and the peak power at the beginning of pass n, divided by the peak power at pass n. If the power gain compensates exactly for the losses and the net gain is zero, the peak power per pass remains constant as long as the pulse properties remain stable. In this way, the seed pulse is reproducible and can support seeding schemes at high repetition rates.  
In this paper we consider two approaches to generate and store a seed laser pulse in cavity.  
1. An oscillator-FEL starting with an external seed laser pulse. An external seed laser initiates the modulation of the first electron bunch and the bunch amplifies the seed pulse to compensate for the power losses in the cavity. The optical cavity feeds back the seed pulse which is used to modulate the following bunches. The shortest wavelength of the modulator is determined by the low repetition rate seed laser source and by the mirror availability.
2. An oscillator-FEL starting from shot-noise. An electron bunch generates radiation along the modulator, which is amplified with the number of passes. This process can be divided into two phases. The \"build-up regime\", where the net gain per pass needs to be positive to build up the peak power required for seeding, and the \"steady-state regime\" where the net gain needs to go back to zero so that the resonator losses are equal to the power gain. In order to transition between these two phases, an active control on the gain per pass is required. In addition, starting from noise means that a SASE spectrum is generated. This needs to be monochromatized. In this case, the shortest wavelength of the modulator is determined by the mirror availability.  
In the following, we consider the implementation of an oscillator-based FEL in support to HGHG and EEHG seeding schemes in order to further extend the tuning range to shorter wavelength and higher repetition rate.
###### Abstract  
This paper presents an optimal design for the inner current-control loop of the continuous current conduction mode (CCM) power factor correction (PFC) stage, which can be used as the front stage of the two-stage AC/DC telecom power supply. The conventional single-phase CCM-PFC boost converter is implemented with proportional-integral (PI) controllers in both the voltage and current-control loops to regulate the output DC voltage to the specified value and to ensure the input current follows the input voltage, which offers a converter with a high-power factor (PF) and low current total harmonic distortion (THD). However, due to the slow dynamic response of the PI controller at the zero-crossing point of the input supply current, the input current cannot fully follow the input voltage, which leads to high THD. In this paper, we investigate a digitally controlled PFC converter with an optimally designed inner current-control loop using a doubly-fed control loops integral-proportional (IP) controller to reduce the THD and to offer an input current with a unity PF. For the economic design of a digitally controlled PFC converter, two isolated AC and DC voltage sensors are designed for interfacing with the microcontroller unit (MCU). PSIM software as well as experimental prototype was used to test the converter performance using the proposed designed current controllers and isolated voltage sensors. We achieved a high-power-density, digitally controlled, telecom PFC stage with a power factor more than 99% and THD of about 5.50%.  
CCM-PFC; small signal model; IP controller; zero-crossing point; total harmonic distortion (THD); power factor (PF); isolated voltage sensors +
Footnote †: journal: Applied Sciences  
_Applied_
# Learning-Based Branching Acceleration for Unit Commitment with Few Training Samples
### Contribution and Organization  
To address the challenges outlined above, this paper introduces an innovative ML-based method termed Branching Acceleration for UC. This method enhances the efficiency of solving UC problems by improving the B&B algorithm, providing an approximate optimal solution. The main contributions of this study are summarized as follows:  
* Branching acceleration for UC transforms the B&B algorithm into a sequential decision problem, employing imitation learning to learn the optimal pruning policy for the B&B tree, thereby enhancing the original policy. This improvement enables the method to effectively prune uncertain, non-optimal nodes, significantly accelerating the B&B algorithm in solving UC problems. It is worth mentioning that by setting the threshold to iteratively expand the search space, the method ensures feasibility while reducing the average search space.
* To further improve the performance of branching acceleration for UC, this study carefully designs the training process and input features of the ML model. Numerical studies demonstrate that the method achieves near-optimal performance with only a few training UC problem instances and low computational complexity, while exhibiting excellent generalization capability under task mismatches. Furthermore, the studies investigate the impact of various threshold settings during the testing phase. Appropriate threshold settings can effectively improve the method's performance while balancing its various performance metrics.
* In contrast to the idea of discarding the original policy of the B&B algorithm in existing related research. Branching acceleration for UC is independent of the B&B algorithm'sstages. It can be seamlessly combined with B&B improvement methods, leveraging the strengths of each to enhance overall performance.  
The rest of this paper is organized as follows: Section 2 presents the formulation of the UC problem, followed by an introduction to the B&B algorithm in Section 3. The key method of this paper, branching acceleration for UC, is proposed in Section 4. Section 5 discusses the numerical studies conducted on various testing systems. Finally, this work is concluded in Section 6.
# Analysis of ICS and SCADA Systems Attacks Using Honeypots
## 4 Main Differences between IT and OT  
Information technology (IT) and operational technology (OT) systems serve different purposes and have different characteristics, making them distinct from one another. Understanding the differences between IT and OT systems is critical for ensuring their security and availability, as well as for making informed decisions about the use of technology in different environments. Table 3 presents the key differences between IT and OT.  
IT systems are typically used to manage and process data, such as in business systems, whereas OT systems are used to control and monitor industrial processes and equipment. IT systems have a focus on confidentiality and integrity, while OT systems prioritize availability and safety. The approach to change is also different, with IT systems being more flexible and able to adapt to rapid change, while OT systems are designed for controlled and predictable change. OT systems are also less dependent on connectivity and are more time-sensitive than IT systems.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Level of Interactivity with Attacker** & **Interact with Host** & **Interact with Program** & **Write Programs** \\ \hline Low & \(\surd\) & x & x \\ \hline Medium & \(\surd\) & \(\surd\) & x \\ \hline High & \(\surd\) & \(\surd\) & \(\surd\) \\ \hline \hline \end{tabular}
\end{table}
Table 2: Classification of honeypots based on the level of interactivity with the attackers [18].  
Figure 1: Types of IoT, IIoT, and CPS honeypots and honeynets [17].  
The confidentiality, integrity, availability (CIA) model is a common framework for understanding and managing the security of information systems. It refers to the three key aspects of security: confidentiality, which ensures that information is only accessible to authorized individuals; integrity, which ensures that information is accurate and has not been tampered with; and availability, which ensures that information is accessible when needed.  
* Confidentiality: This is safeguarding against unauthorized access to or disclosure of sensitive information.
* Integrity: This is the safeguarding of data against unauthorized alteration or manipulation.
* Availability: This describes the readiness of the information system for usage by authorized users.  
The availability, integrity, confidentiality (AIC) model is a similar framework, but the focus is on the three key aspects of security for the availability of data and systems. The AIC model is often used in the context of information security and privacy, especially in the OT industries.
## 1 Introduction
In recent years, diffusion models have gained widespread attention in image generation and restoration. Unlike traditional denoising autoencoders, diffusion models progressively model the data by adding noise through a forward process, then reverse this process via a carefully designed denoising procedure to achieve high-quality sample generation [37; 38; 39]. This model architecture endows diffusion models with powerful capabilities in image restoration and denoising. By employing diffusion models as a preprocessing module, the subsequent model's denoising performance can be effectively improved. Meanwhile, vision transformers have also been advancing rapidly. Compared to convolutional networks, transformers can model long-range dependencies via the self-attention mechanism and capture information from different representational subspaces through multi-head self-attention [40]. Swin Transformer (SwinT) reduces the computational and memory costs substantially through the shifted window attention design and hierarchical representation [41; 42]. It is one of the important advancements in vision transformer architectures. Since radar jamming signal time-frequency graphs contain relatively complex global patterns, using SwinT can better learn their global feature representations and boost jamming recognition performance. This paper proposes using diffusion models as the preprocessing module to denoise the input signals, then utilizing SwinT to extract global features from the time-frequency graphs, in order to further improve radar jamming recognition capabilities. The combination of these two models provides new insights for jamming recognition in complex scenarios.The overall framework of the proposed method is shown in Figure 1.  
This paper first establishes mathematical models for 8 common radar jamming patterns in Section 2, providing the basis for subsequent analyses and experiments. Section 3 then proposes a novel jamming recognition framework integrating multiple techniquesincluding CWD time-frequency graph representation, diffusion models for denoising, SwinT for feature extraction, and customized loss functions. Simulations and experiments are conducted in Section 4 to demonstrate the effectiveness and robustness of the proposed method under various conditions. Finally, Section 5 summarizes the critical innovations and contributions of this work.
## 1 Introduction
This paper therefore describes the damping efficiency of a prototype semi-active hydraulic damper whose actual force is controlled in real time by the controlled bypass between the minimum and maximum damping forces due to the fully open and fully closed bypass valve. The adopted control law is clipped viscous damping with negative stiffness whose viscous coefficient is adjusted to the actual frequency of motion in real time generating optimum modal damping and the negative stiffness force helps to increase the damper motion in order to dissipate more energy than the passive damper. The implementation of the control law in programmable logic control (PLC) is explained and the according control flow chart is presented. Furthermore, it is explained how the control force tracking task is solved without the use of a force feedback in order to save the costs of a force transducer for each semi-active cable damper. The cable damping ratios resulting from this adaptive damper with the consideration of the minimum and maximum damper force constraints are computed for the first four cable modes, for typical damper positions, for a taut string cable model and for a cable model with the effects of bending rigidity and fixed support conditions. The results are compared to those obtained from the passive linear viscous damper being optimized to one targeted mode and the passive linear viscous damper being optimized to the first four targeted modes. The former benchmark is a theoretical one because transverse dampers are never optimized to one modal component only while the latter benchmark represents the practical one. The comparative study demonstrates that the proposed prototype semi-active damper significantly enhances the cable damping ratios of the targeted modes even with the control force limitations due to the fully open and fully closed bypass valve.
# High Spatio-Temporal Resolution CYGNSS Soil Moisture Estimates Using Artificial Neural Networks
## 3 Soil Moisture Retrieval Methodology
Throughout this section, insights into the ANN model architecture will be provided first, then detailed information about the data sets that are used in this study will be given, and, finally, how the data sets are used in the learning process (training and validation) will be explained.
# An Analysis of Cloud Security Frameworks, Problems and Proposed Solutions
## 2 Literature Review
### Cloud Security Frameworks  
#### 2.1.1 Ability of Framework  
Cloud security frameworks are designed to ensure an organization's data's confidentiality, integrity and availability in a cloud environment [3]. Undertook a critical examination of the usefulness of new security frameworks in increasing cloud security. The study aims to analyze and evaluate various cloud security standards and frameworks to assess their strengths, limitations, and overall influence on improving cloud security posture. The authors undertook a thorough examination of many well-known cloud security frameworks, including the Cloud Security Alliance (CSA) Security Guidance, the NIST Cloud Computing Security Reference Architecture, and the ISO/IEC 27017:2015 Cloud Security Controls. These frameworks were assessed based on their ability to meet important cloud security concerns such as data protection, access management, encryption, and incident response. The study revealed the benefits and drawbacks of each framework through a comparison. It provided readers with insights into the precise security controls and recommendations provided by these standards, allowing them to grasp their application and significance in various cloud deployment models. Furthermore, the study looked at how new security frameworks fared compared to earlier standards [5].  
[PERSON]'s [5] research paper adds to the current body of knowledge by offering a complete comparison of cloud security standards and frameworks. It is a great resource for practitioners and academics who want to understand the strengths and limitations of various security frameworks and make educated decisions when adopting cloud security. Key difficulties in cloud computing, according to Gartner, include governance, cloud environment selection, and security/privacy. Cloud investments should be guided by the board of directors in order to minimize risk, regulate expenses, and produce profit [7]. Table 1 will describe the perspective, different conversional topics and future work or gaps of cloud security frameworks.