esa-sceva/satcom-chunk-collection huggingface dataset:
## 1 Introduction
The vital issue for millions of customers, connected with the calibration quality of energy meters, is presented in [21]. The paper concerns research focused on the accurate assessment of the commonly used static energy meters. In some specific load conditions, their indications can differ by more than 580% when compared to the conventional (electromechanical) energy meters. The research was performed in accordance with the relevant standards of test setups. The research included the energy meters equipped with a variety of current sensors. However, the question, \"What is the cause of an error in the processing characteristics of the energy meters?\", remains unanswered. In the context of this investigation, the necessity to measure the quality of the electrical energy is becoming increasingly important, because the number of non-linear and variable-energy loads connected to the electrical network is constantly growing. The descriptions of the methods and systems for electrical power quality assessment, in their various aspects, can be found, e.g., in [22; 23; 24; 25; 26; 27]. In [28; 29; 30], issues concerning the configuration and operation of the measurement track of the \"estimator/analyzer\" (E/A) instrument for the designation of electrical power quality coefficients, especially for ship power network estimations, were considered. Additionally, considerations connected with investigating the characteristics of the E/A measurement tracks are described in [31; 32; 33]. Further detailed analyses are based on the case study concerning the designed and constructed instrument, in the area under consideration. The author of the present paper uses the term \"calibration\", which can be defined as: \"a test during which known values of measures are applied to the device input and corresponding output readings are recorded under specified conditions\". A related notion of \"validation\", which in engineering means confirming that a product or service meets the needs of its users, is used in this paper. An overview of the selected validation methods can be found in [34]. For the user of a specific instrument, it is difficult to assess the correctness of the instruments' indications during the measurement operation. They can only relay on the declarations of the instrument manufacturer. This work is focused on the method of reliable validation of the E/A instrument characteristics. The main goal of this paper is to show the solution used in the developed instrument. The paper deals with an additional configuration, necessary to implement the validation procedures of the algorithms applied in the E/A instrument. In Section 2, the measurement functions, as well as the basic measurement algorithms, implemented in the instrument are in short given. Section 3 describes the calibration procedures applied during the examination of the instrument. The constraints of the procedures used are mentioned. Section 4 presents the proposal of a reliable method for the validation of measurement algorithms implemented in the instrument measurement functions as embedded processor software. This work is summarized in Section 5.
## 6 Skin Conditions and Evidence of the Beneficial Role of Vitamin D
### Atopic Dermatitis  
Greater geographic latitudes display greater rates of atopic dermatitis (AD), which is correlated with reduced sun exposure and a decreased generation of vitamin D [195]. AD is a chronic, recurrent inflammatory disease, characterized by pruritus and eczematous lesions, that affects approximately 20% of children and 7.2% of adults, globally [41]. The primary cause of AD is the malfunction in the synthesis of the epidermal barrier and a change in the cutaneous immune system, which impacts mainly filaggrin [196]. Topical vitamin D enhances skin barrier function by promoting keratinocyte differentiation and the formation of antimicrobial peptides like cathelicidin, therefore decreasing _Staphylococcus aureus_ colonization, which is a common aggravating AD factor [202,203].  
Vitamin D is known to regulate the integrity and permeability of the epidermal barrier, although its exact role in this process is still unknown [38]. There has been a long debate concerning the efficacy of oral vitamin D as an AD supplement. Low serum vitamin D levels, especially during winter, have been linked in several studies to the progression and severity of the illness. However, the exact role that vitamin D plays in the pathophysiology of AD remains unclear [197]. Serum vitamin D levels were shown to be considerably lower in moderate and severe AD than in mild AD, in a recent study conducted in Spain, but this link was only significant for patients with light Fitzpatrick skin types (study involving 134 children with AD and 105 control samples, without AD) [40].  
To sum up, there is no clear evidence pointing out the importance of dietary vitamin D as an AD treatment [39]. Further investigation should be conducted to prove the importance of vitamin D supplementation in such types of patients. Conversely, animal investigations using topical vitamin D analogs have been claimed to cause AD, mostly via activating TSLP in keratinocytes [198]. TSLP acts as a switch for the T-helper 2 (Th2) allergic inflammation, a common characteristic of AD, and is necessary for the induction of pro-inflammatory chemokines--mostly IL-4, IL-13, and IL-31 in AD (Table 3) [199].
## 3 Components of VPN Architecture
### SSI/TLS Based VPN  
SSL/TLS VPN (Secure Sockets Layer VPN) provides a standard VPN solution based on a Web browser in Transport Layer or developed using specific client/server applications [7, 8]. Sockets are used for data transfer between sender and receiver. There are two general deployments for SSL/TLS VPN implementation.  
SSL/TLS Portal VPN - SSL/TLS Portal VPN: In this scenario, secure service access is achieved with a single standard SSL/TLS connection to the target web server. The client can access the SSL/TLS VPN gateway via a standard web browser, providing the necessary parameters to negotiate authentication [9].  
SSL/TLS Tunnel VPN: In this scenario the VPN client can access multiple network services/hosts (this is the case with OpenVPN, OpenConnect, and SSTP). In the classic SSL/TLS communication, two keys are used to encrypt the data, the public one, shared among all, and the private one, typical of each endpoint. To further increase the level of security, two-factor authentication can be used by far or also OTP. In IPsec communication, once the client is authenticated to the VPN, it has full access to the private network, while in SSL/TLS VPN you have control of the more granular access, which allows you to create specific tunnels for applications via sockets rather than for the entire network, also creating specific \"access roles\" (access profile with specific rights for different users).
# A Multichannel-Based Deep Learning Framework for Ocean SAR Scene Classification
## 3 MCNN Framework for Geophysical Phenomenon Classification  
In this section, we introduce a novel neural network, referred to as the multichannel neural network (MCNN), which integrates the multichannel features derived from the original input for the purpose of classifying the aforementioned ten predefined geophysical phenomena shown in Figure 2. The comprehensive architecture of the MCNN algorithm, encompassing multi-feature fusion, data augmentation, and multichannel feature extraction, is visually depicted in Figure 4.  
The multi-feature fusion module incorporates an efficient image edge filter to selectively preserve intricate details pertaining to oceanic phenomena present in SAR images, concurrently mitigating the disruptive effects of speckle noise. Hence, the multichannel characteristics of the input are integrated with the original SAR imagettes, along with the associated gradient magnitude derived from the applied filter. And then, feature augmentation such as horizontal translation and reflection is implemented to address the challenge of limited sample size. This approach aims to mitigate the small-sample problem by expanding both the volume and diversity of the training dataset. Furthermore, the feature extraction module utilizes a multichannel approach employing transfer-learning techniques to address constraints imposed by limited dataset sizes. Specifically, the Inception-ResNet architecture [56] is strategically chosen to strike a favorable balance between a substantial parameter count and optimal classification performance. Finally, some important weights are optimized with our softmax function to implement optimal parameter decision for oceanic phenomenon classification. The subsequent sections comprehensively detail the different parts of our MCNN algorithm.  
Figure 4: Architecture of the MCNN algorithm. The architecture includes multi-feature fusion, data augmentation, and multichannel feature extraction modules. In data augmentation stage, ‘D’ and ‘G’ stand for discriminator and generator respectively. In the multichannel feature extraction module, the stem block contains 9 convolutional and max pooling layers. Inception-ResNet A to C are modularized blocks comprising a series of convolutional and max pooling layers.
## 2 Research Method  
### Electrical Resistivity Tomography (ERT)  
In terms of the measuring principle of ERT, the direct current or low-frequency alternating direct current is conducted to the ground through a pair of current electrodes, C1 and C2, to establish a man-made electric field. The electric field is measured using another pair of potential electrodes, P1 and P2, so as to measure the potential difference between P1 and P2, different configurations of electrodes (e.g., Wenner, pole-dipole, Schlumberger, dipole-dipole, and pole-pole), and the movement of electrodes that correspond to different space geometry factors. Thus, apparent resistivity can be obtained. The resistivity measured infield is not the true resistivity of the subsurface structures. Therefore, the apparent resistivity needs to be calculated via an inversion analysis to obtain the approximately real resistivity profile [39].  
The direct current resistivity method includes 1D, 2D, and 3D detection methods. The advantage of a 1D survey is a rapid measurement, but the defect is that it cannot consider the transverse resistivity variation, thus affecting the reliability of measurement results and interpretation. In the last few decades, to enhance the accuracy of the electrical prospecting method in result interpretation, the researchers developed the 2D survey from the pseudo depth composed of the VES and profiling results of the 1D survey. As the 2D-ERT has a low cost and short test time, the apparent underground resistivity is obtained by wiring laid, and the resistivity of subsurface soil is obtained by appropriate inverse calculation. In recent years, more research has been devoted to the research on 3D measurement, leading to higher accuracy of 3D detection. However, the effectiveness of 3D detection is still under investigation and is limited to the measurement of space and time [41; 42; 43; 44; 45]. Thus, 2D detection is still the most economical and feasible measurement method at present.  
To select the test site, several underground tunnel vent holes were found on the surface of a site according to the tunnel literature, indicating a possible presence of an underground tunnel. In order to evaluate the location, size, and depth data of this tunnel, this study attempted ERT detection.  
Therefore, three survey lines, L1, L2, and L3, were laid in the Shuangru Mountain Barrack Field, as shown in Figure 1. The overall length of each survey line was 46 m, the electrode spacing was 2 m. The three survey lines were parallel with each other. The distance between L1 and L2 was 5 m, the distance between L2 and L3 was 8 m. The electrode configuration used Wenner Array for data collection infield measurement. Thistest used the SYSCAL PRO Switch 48 ground resistance instrument of France IRIS. In this experiment, the analysis software Res2 dinv (version 3.54 z) [39] developed by Geotomo was used for inverse analysis. The inverse analysis method used the optimal least square method (L2 norm). To ensure the measurement quality, each survey line was measured repeatedly to ensure the deviation was below 3%.
# Parallel Complex Quadrature Spatial Modulation
## 6 Simulation Results
\begin{table}
\begin{tabular}{c c} \hline \hline \(\mathbf{(}N_{t},\,N_{r},\,\mathbf{M}\mathbf{)}\) & \(\theta_{opt}\) (\({}^{\circ}\)) \\ \hline \((256,\,4,\,4)\) & \(36\) \\ \((256,\,4,\,16)\) & \(44\) \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Optimal rotation angle, \(\theta_{opt}\), for CQSM system configurations. tolerable given the huge gains in the terms of the number of required antennas for high \(p\) values. To provide a fair comparison between the performances of PQSM and PCQSM, the same number of antenna groups is selected. The number of transmit antennas required in the two schemes is the same. However, to achieve the same spectral efficiency, PQSM requires higher modulation orders. Figure 4b depicts the error performance of the two systems for two configurations. While PQSM requires 16-QAM modulation to achieve a spectral efficiency of 20 bit/s/Hz, PCQSM on the contrary requires 4-QAM. As a result, the PCQSM outperforms PQSM by approximately 4 dB in both groups at a target BER of \(10^{-4}\). Finally, PCQSM is compared with the three conventional SM schemes to achieve the same spectral efficiency of 24 bit/s/Hz, using the same modulation order of \(M=16\). QSM requires 1024 transmit antennas, CQSM requires 256, PQSM (\(P=2\)) requires 64,  
Figure 4: Performance comparison of **(a)** SM schemes with transmission rate of 20 bits/s/Hz with same number of receive antenna, \(N_{r}=4\) and modulation order \(M=4\)-QAM. **(b)** PQSM and PCQSM schemes with 2 and 4 groups to achieve a transmission rate of 20 bits/s/Hz, \(N_{r}=4\). Figure 3: Theoretical performance of PCQSM in comparison with PCQSM simulation for **(a)**\(P=2\) and **(b)**\(P=4\) at a transmission rate of 14 bits/s/Hz with 8-QAM, \(N_{t}=8\) and \(N_{r}=4,6\), and 8, respectively. and PCQSM \((P=2)\) requires 32, the least number of transmit antenna, to achieve the same spectral efficiency of 24 bit/s/Hz. Figure 5 illustrates the BER performance of these transmission schemes. At a BER of \(10^{-4}\), PCQSM \((P=2)\) attained negligible BER difference when compared to that of CQSM, and about 1 dB improvement as compared to QSM and PQSM \((P=2)\).
# Research on Shear Behavior of Sand-Structure Interface Based on Monotonic and Cyclic Tests
## Materials and Experimental Process  
### Test Soil  
The sand used in this test was taken from Fujian, China, and its particle grading curve is shown in Figure 2. Table 1 lists the properties of the sand.
_Applied_  
_sciences_  
_Article_  
Network Calculus Approach for Packet Delay Variation  
Analysis of Multi-Hop Wired Networks  
**[PERSON] \({}^{\star}\), [PERSON], [PERSON] \({}^{\copyright}\) and [PERSON]**  
Division of Networked and Embedded Systems, Malardalen University, 721 23 Vasteras, Sweden  
\({}^{\star}\) Correspondence: [EMAIL_ADDRESS]  
**Abstract: The Industrial Internet of Things (IIoT) has revolutionized businesses by changing the way data are used to make products and services more efficient, reliable, and profitable. To achieve the improvement goals, the IIoT must guarantee the real-time performance of industrial applications such as motion control, by providing stringent quality of service (QoS) assurances for their (industrial applications) communication networks. An application or service may malfunction without adequate network QoS, resulting in potential product failures. Since an acceptable end-to-end delay and low jitter or packet delay variation (PDV) are closely related to quality of service (QoS), their impact is significant in ensuring the real-time performance of industrial applications. Although a communication network topology ensures certain jitter levels, its real-life performance is affected by dynamic traffic due to the changing number of devices, services, and applications present in the communication network. Hence, it is essential to study the jitter experienced by real-time traffic in the presence of background traffic and how it can be maintained within the limits to ensure a certain level of QoS. This paper presents a probabilistic network calculus approach that uses moment-generating functions to analyze the delay and PDV incurred by the traffic flows of interest in a wired packet switched multi-stage network. The presented work derives closed-form, end-to-end, probabilistic performance bounds for delay and PDV for several servers in series in the presence of background traffic. The PDV analysis conducted with the help of a Markovian traffic model for background traffic showed that the parameters from the background traffic significantly impact PDV and that PDV can be maintained under the limits by controlling the shape of the background traffic. For the studied configurations, the model parameters can change the PDV bound from 1 ms to 100 ms. The results indicated the possibility of using the model parameters as a shaper of the background traffic. Thus, the analysis can be beneficial in providing QoS assurances for real-time applications.  
**Keywords: packet delay variation; jitter; QoS; packet delay; moment-generating functions; network calculus; Markovian on-off model**
## 1 Introduction
Moreover, traditional control methods can cause frequency fluctuation and power imbalance of the power grid when the power output is unstable or the load changes, which is against the operation safety and the stability of the power grid. Therefore, the capability to maintain the stability of the lower grid connected to the output stage, as well as provide friendly support to the upper grid, is of great significance for improving the stability of entire AC/DC hybrid distribution network. Based on the mentioned considerations, this paper proposes a novel PET that is applicable for an AC/DC hybrid distribution network. The input stage utilizes MMC and applies the virtual synchronous machine (VSM) control strategy to improve the inertia and damping of the system, which is more friendly to the upper power grid. The isolation stage applies a combined connection of input-series output-series (ISOS) and input-series output-parallel (ISOP), which effectively reduces the amount of DC/DC modules used, increases the flexibility of access to AC/DC distribution networks of multi-voltage levels, and improves economic benefits. The output stage enables the PET to respond to the frequency fluctuation of the upper power grid and participate in primary frequency regulation (PFR) through controlling the power of the DC output port, which improves the stability of the power grid. In addition, a power coordination control method is proposed that can coordinate power flows among every port when the power demand of the output stage changes, by means of adjusting the high-voltage DC voltage of the input and isolation stages.
# An Approach to Designing Critical Railway Voice Communication
## 5 Use Cases of Critical Voice Communication Applications
The MUTC service retrieves the application data from the ADM service. A request to talk is indicated by a call participant to the MUTC application and the MUTC service is notified. The MUTC service submits a request to the policy service to decide how to proceed. The policy service can grant/revoke/reject the permission to talk if the number of simultaneous talkers is not maximal or delegate the talker selection to the controller as the entitled call participant. The MUTC application is notified about the decision and indicates the outcome of the request to the associated call parties about the grant/rejection to talk. Each of the simultaneous calls has requirements for high bandwidth and the resources available for the slice dedicated to emergencies may be insufficient. The controller decides  
Figure 12: Services interaction flow for communication authorization. to focus on one of the video calls and the controller's critical communication application activates the QoS class negotiation application. The QoS class negotiation application retrieves the user profile from the UPM service and requests a dynamic upgrade of the QoS class of the respective video call from the QoS negotiation service by providing information about the video call's prioritization and other relevant information. The QoS class negotiation application subscribes to notifications related to the updated QoS class and receives notifications about such events. Figure 13 illustrates the flow of multiuser talker control and dynamic QoS class negotiation. Figure 13: Services interaction flow for multiuser talker control and QoS class negotiation. During the call, a railway staff member who is not at the location of the fire makes a call to the same controller. The railway staff member is presented with their functional identity. The arbitration application is activated to retrieve the location and functional identity profile of the railway staff member from the location service and the FIPM service, as well as the arbitration requests between competing communications from the policy service, providing information about the functional identities of the controller and the railway staff member. The policy service decides to automatically reject the call for the railway staff member. The controller needs to receive more information from the train conductor and sends a message to the conductor to join the ongoing call. The IUM application is activated. The communication is authorized based on the controller's and train conductor's functional identities, as well as the conductor's location. The arbitration application allows the outgoing competing communication also based on a predefined policy. Figure 14 illustrates the arbitration between competing communications and invite-a-user messaging.