esa-sceva/satcom-chunk-collection huggingface dataset:
# A Multicomponent Face Verification and Identification System
## 3 Results
### Mixed Reality Glasses  
In Figure 9 (left) the case of the utilization of the MR glasses in real-time terms is presented. The associated face identification results are depicted in Figure 9 (right).  
The idea of importing into an MR HMD, the face image capturing functionality along with the results coming from the _Backend service_ related to the face identification processing, came up due to two main reasons. At first, MR HMDs allow users to operate hands-free by enabling eye tracking commands, hand recognition and interactions, or even voice commands. Moreover, the operation is similar to a mobile device, meaning it uses a camera input for video and image capturing and is easy to establish data exchange with services. Finally, the HMD setup enables the possibility to experiment with advanced visualizations in space by utilizing spatial information coming from MR glasses.  
The user should first log in with the related credentials. The application was developed in Unity for Hololens 2 (UWP MR glasses). The application starts using its camera as input. Each camera frame is processed by a face detection model with the sole purpose to detect faces and their corresponding bounding boxes. Two of the texted ML models are FaceONNX and BlazeFace. Inference of face detection models was run on the device (Hololens 2) to achieve real-time results and provided as results the recognition confidence and the area on the image where a face was detected. To forward a single face as input to the _Backend service_ for the face identification, only the face detection result with the highest confidence is taken under consideration for each frame. As postprocessing, the image is cropped and shared to the _Backend service_ for the face identification process getting as a result the recognized person metadata such as the name, surname, etc.  
For advanced spatial visualizations we experimented with combining the Hololens 2 spatial mapping feature, which generates meshes for each detected surface, which includes human bodies. This means that human bodies and surfaces are represented as low poly meshes with no detail that are interactable using colliders. We leveraged this functionality to create a projection method that utilized a ray-cast from the center of the face detection bounding box and its corresponding position on the camera field of view toward the dynamic generated mesh as a simplistic way to overlay results coming from the face identification process on top of the human's position in real space. According to the real  
Figure 9: (**Left**) Utilization of the MR glasses in real-time terms. (**Right**) Face identification results via the MR glasses.  
time experiments, the total processing mean time for the execution of a face identification process and related visualization via the MR glasses was measured as 0.15 s.
## 1 Introduction
The parameterized analysis of the results shows the potential to improve the design considering the cooperative management of the MG, which allows the minimization of costs, the minimization of the size and usage of support systems and a significant improvement in the reliability of the system as a whole. Thus, the main novelty of this work is the possibility of achieving an optimized design of a set of interconnected facilities, studying their reliability through a parameterized analysis. With the results of the analysis, it is possible to select the most appropriate design alternative according to the selected objectives. The specific objectives that have been addressed in this work and that represent the novelty of the study are detailed below. 1. Study the reliability of a set of two dwellings with their respective SAPV energy systems when operating with a cooperative strategy. 2. Improve the design of all the systems considering global reliability. 3. Analyse the impact of the cooperative strategy on the reliability and design of the systems. In addition, as another novel aspect in the procedure used in this study, random failures in the generation system are considered to analyse supply reliability, in addition to the use of demand and generation curves with a random combination so that the result is consistent and robust. These random failures are generated following typical distributions extracted from scientific works. With the presented method the authors try to address the gap identified in the literature of the optimal design and management in microgrids considering costs and reliability as the main targets. The novelty of the presented work relies on the practical application of a simple strategy to a rural area considering real data and random failures of the system to optimise the design of the components and the management with a cooperative strategy. This problem including cooperation between both systems represents a challenge that takes place in many isolated areas in the developed countries. The results of the method provide an economic benefit from the planning stage of the microgrid and an increase in the reliability of the participants' energy supply, which is one of the main gaps in scientific publications. The rest of the article has been structured as follows. Section 2 shows the materials and methods, summarizing the individual design of the dwellings using the method developed in [38] and proposing the cooperative management strategy to be used for the SMC in the selected scenarios. Section 3 shows the results of the SMC simulation comparing the system without interconnection with the system as an MG. Next, Section 4 shows the discussion of the results. Finally, Section 5 shows the conclusions of the study.
# Reliability Analysis of CFRP-Packaged FBG Sensors Using FMEA and FTA Techniques
## 2 The principle and structure of CFRP-packaged FBG sensors
### The Structure of CFRP-packaged FBG Sensors Used in WTB Full-Scale Structural Testing  
A CFRP-packaged FBG sensor is a kind of \"sandwich\" structure, which mainly includes (see Figure 5): FBG sensor (FBG), CFRP packaging layer (PL), and bonding layer (BL). The PL is used to protect the FBG sensor, which contains a layer of carbon fiber placed above the FBG sensor and another two layers placed below. The BL is used to bond the CFRP-packaged FBG sensor to the blade surface. A certain number of CFRP-packaged FBG sensors are series linked by connecting components (CC), and finally connected to the FBG demodulator (FBG-D).  
The strain transfer process of the CFRP-packaged FBG sensor is shown in Figure 6. In particular, the axial strain of the blade surface occurs under the action of external load, and in turn, it transfers from the blade surface to the bonding layer, the packaging layer, and the FBG sensor by shear force, and then the optical fiber generates axial strain, which causes the wavelength of the grating to change [24].
# Simulation Modelling of Silicon Gated Field Emitter Based Electronic Circuits
## 4 Conclusions  
In summary, this study explores the modeling of a variety of VT-based circuits. In addition, and more importantly, we successfully simulated several oscillator and logic circuit designs based on an optimal VT. To the best of our knowledge, it is the first demonstration of a vacuum-state oscillator in the circuit simulation module in which the VT functions as a conventional triode or field-effect transistor (FET). Several circuits, a Wein oscillator, a Ring oscillator, a NOR gate, and a NAND circuit, were designed and demonstrated using LTspice simulations. The low-frequency Wein oscillator circuit has an oscillation frequency of 102 kHz with an amplitude of 26 V\({}_{\mathrm{PP}}\). The Ring oscillator model showed a comparatively higher oscillation frequency of 1.14 MHz with a magnitude of 4 V\({}_{\mathrm{PP}}\). These oscillators and logic circuits could be used as low-frequency harsh environment temperature, pressure, and vibration sensors in nuclear reactors, satellites, and spacecraft. Future work includes the experimental validation of these circuits.  
Methodology, R.B.; Software, R.H.; Validation, R.H. and J.B.; Investigation, R.B.; Resources, W.C. and G.R.; Data curation, R.B.; Writing--original draft, R.B.; Writing--review & editing, J.B.; Funding acquisition, A.I.A. and J.B. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the Air Force Office of Scientific Research under grant FA9550-18-1-0436.  
Not applicable.  
The data presented in this study are available in the article.  
The authors declare no conflict of interest.
# Automatic Refactoring Approach for Asynchronous Mechanisms with CompletableFuture
## 4 Empirical Research
### Executor Inheritance Structure Analysis
#### 5.3.2 Executor Overriding Analysis  
In addition to delegate executor types, the characteristic of code reuse through inheritance in object-oriented programming also provides a possibility for identifying refactorable executor types. If executor types internal to JUC meet the refactoring conditions, then executor types that inherit from those within JUC and do not override instance methods that could affect submit or execute still meet the refactoring conditions. This section first defines key methods, followed by the definition of refactorable executor types.  
**Definition 7**.: _Key Methods: For the executor type RT that has been determined to be refactorable, its key methods are the submit method and the execute method, as well as all non-private and non-final instance methods that are directly or indirectly called within the class. The formal definition is:_  
\[\text{CM}(RT)=\{\text{submit,execute}\}\cup\left\{m\middle|_{\
eg(\text{`` private''}\in\text{modiMethod}(m)\vee\text{``final''}\in\text{modiMethod}(m)\vee\text{``static''}\in\text{modiMethod}(m))}\right\} \tag{8}\]  
**Definition 8**.: _Refactorable Executor Type Set: We define the refactorable executor type set RTS as a specific group of executor classes. The method of judgment involves traversing the inheritance structure of AbstractExecutorService; if it is not part of JUC and its direct parent is a refactorable type, then by obtaining the key methods of the direct parent, we determine whether the current type overrides to identify refactorable executor types. The formal definition is as follows:_  
\[\text{RTS}=\text{ExecutorInJUC}\cup\left\{RT\middle|_{\begin{subarray}{c}RT \in\text{allSubTypes}(\text{AbstractExecutorService})\wedge RT\
otin\text{ ExecutorInJUC}\wedge\\ getSuperClass(RT)\in\text{RTS}\wedge\text{declarMethods}(RT)\cap \text{CM}(getSuperClass(RT))=\varnothing\end{subarray}\right\} \tag{9}\]  
where  
ExecutorInJUC represents the set of executor types within JUC.  
getSuperClass(T) returns the direct parent class of type T.  
declarMethods(T) returns the set of methods declared in type T.
# LPWAN-Based Vehicular Monitoring Platform with a Generic IP Network Interface
## 1 Introduction
While the integration of cellular technologies in the vehicular ecosystem has been deeply studied in the past years [10; 11; 12], the use of LPWAN-based solutions in this area has not been exploited yet [13; 14; 15], and they could present a real alternative for battery-constrained transport means, such as scooters or bikes. Therefore, in this work we focus on the concept introduced in Figure 1 and propose a flexible and extensible end-to-end monitoring platform for vehicles, taking advantage of LPWAN as either the sole communication technology, or hybridized with others. We have developed the different modules of a system, that ranges from data extraction by using the On-Board Diagnostics II (OBD-II) protocol (telemetry application), to their presentation by developing a cloud-based dashboard system. As depicted in Figure 1, the data transmission from the On-Board Unit (OBU) to the infrastructure has been carried out by means of an LPWAN solution, namely LoRaWAN, with the aim of obtaining a long-distance and reliable monitoring system. In addition, we have designed and implemented a generic network interface for Linux-based systems, that permits the sending of application-layer packets through the LPWAN link using IPv6 and UDP, and using a compression mechanism based on IETF, works for these kind of networks. To the authors' knowledge, this is the first implementation of an LPWAN-oriented network interface ready to use in normal operating systems. An experimental test-bench has been deployed, in order to demonstrate the validity of the proposed monitoring platform, which enables the tracking of vehicle position as well as mechanical status, among others. Thus, the main contributions of this work are the following: (i) A real monitoring platform for vehicles using LPWAN has been designed and developed, (ii) a performance study of LoRaWAN technology in vehicular scenarios has been conducted, and (iii) a generic Linux interface that enables direct and seamless transmission of application-layer data has been implemented. The rest of the document is organized as follows: Section 2 reviews the related work regarding on-line monitoring systems for vehicles. An initial review of the main technologies used in the solution is given in Section 3, including LoRaWAN and IETF LPWAN compression. Next, Section 4 explores the proposed architecture. Section 5 describes the implemented development, as well as the test-bench employed for obtaining the validation results, which are showed and discussed in Section 6. Finally, the paper is concluded in Section 7, summarizing the main achievements and including future research lines.
## 2 An Overview of the Cellular Networks  
Cellular networks, also referred to as mobile networks, can be viewed as the wireless extensions of traditional PSTN (Public Switched Telephone Network) and ISDN (Integrated Services Digital Network) systems. They support wireless communication between mobile devices for both voice and data transmissions, and allow for seamless nation or even worldwide roaming with the same mobile phone. Though in the past, cellular systems were developed by individual entities (companies, countries, etc.), today, cellular communications are based on standard definitions, and they span the entire globe. Different cellular technologies have been proposed over the years, each with its own peculiarities. A detailed account of the technical characteristics of wireless and cellular networks, such as the distinctive features of signals and antennas, can be found in many textbooks (see, for instance, [28; 29; 30]).  
Our perspective here is different: we aim at providing a comprehensive conceptual model of cellular networks that captures all data relevant from the point of view of mobile devices; that is, rather than turning cellular network standards into a conceptual model, we build a representation that suitably integrates those elements that can be gathered by devices on the field (elements that, as we shall see, may not be contained in or differ from those actually declared in the standards). Such a model can then be exploited in several ways; for instance, it may help in answering individual positioning requests and in analyzing the behavior of large sets of devices (e.g., one may be interested in identifying recurring trajectories, or more generally, the spatial and temporal distributions of moving devices [31]). Furthermore, the model can be useful to check whether new observations are consistent with respect to the previously acquired information about the network, thereby allowing one to detect anomalies in the data and changes to the overall network arrangement.  
In this section, to set the groundwork for the rest of the work, we describe the relevant architectural and administrative characteristics common to all existing cellular networks and the difficulties pertaining to their modeling. The interested reader may find the details of the specific mobile communication technologies (GSM, UMTS, LTE) in the Appendix A.  
For the purpose of clarity, in Table 1, we provide a list of technical acronyms that will be used throughout the paper.
###### Abstract  
A joint communication jamming waveform is proposed in this study based on the FBMC-chirp. To increase the number of false targets in a single pulse period, the chirp signal is modulated to different subcarrier groups. Since the subcarriers of the FBMC-OQAM signal are orthogonal, the signals are naturally orthogonal. This allows the transmitter and receiver to be separated and achieve multiple false target jamming, allowing the CFAR threshold to be raised by about 20 dB and protecting the target from detection. The ratio of the frequency shift of the designed jamming signal to the frequency modulation depends on the delay time, making the joint signal more robust in response to jamming and resistant to frequency modulation. The use of intercepted radar signals allowed channel estimation, providing high-speed digital transmission while ensuring multi-false-target jamming. The simulation results show that the joint signal has jamming effects on the pulse Doppler radar. The proposed FBMC chirp joint waveform requires about 20 dB less jamming signal ratio than the existing method, and thus the energy saved can ensure the robust performance of the communication subsystem in the joint communication jamming system. The proposed system has excelled in communication rate and bit error rate performance, ensuring that instructions are accurately and completely transmitted while implementing effective jamming.  
joint communication and jamming; filter bank multicarrier (FBMC); FBMC chirp waveform; waveform design 2023
## 4 Results
### Technical Feasibility
Differences between best-in-class and local AM machines are outlined in Table 4, focusing on the most relevant direct AM processes in production. \begin{table}
\begin{tabular}{c c c c c} \hline \hline  
Figure 3: Technical barrier analysis of limited build chamber volumes for demanded spare part sizes. In Figure 4, the percentages of components, which can currently be manufactured as one component in build envelopes of AM machines are shown. Thus, build envelope values for all listed AM processes are taken from Table 4 and transferred to the build envelope graph in Figure 3 (single dimensions are calculated by assuming cubic build envelopes). As a result, the proportions of parts fitting into the specific build chambers can be identified. The share of 3D printable components of best-in-class machines for all investigated AM processes varies between 63% (i.e., metal-based PBF, metal-based Binder Jetting (BJ)) and 93% (i.e., plastic-based PBF). For locally produced components, a range of 0% (i.e., metal-based BJ) and 72% (i.e., plastic-based BJ) is calculated. Differences in the share of printable components are identified for all AM processes except for p-BJ, in this case, the locally installed AM system represents the best-in-class machine in terms of build envelopes. On average, a share of 47% for local printability and 76% for best-in-class machines is obtained. Obviously, the average share of printable components is significantly lower in the case of local production compared to all best-in-class machines; these machines are only reasonable for high manufacturing throughput, for which the demand for additively manufactured components is currently not present. A limitation in the approach of calculating the share of printable components for specific AM processes from a general demand curve for part sizes must be seen in material dependencies. For some materials, a large share of small parts might be needed, while others demand larger dimensions. This limitation was taken into account because questions regarding size distributions of specific materials would have been too challenging to be answered by the participants in this survey. Summarized, in this study, 70% of requested materials are considered as additively manufacturable. In 1 out of 14 investigated cases, the underlying process and machine-related surface roughness met the requested values, 47% and 76% of components fit into largest local and best-in-class build envelopes. This leads us to believe that all mentioned technical barriers imply real obstacles in specific cases since special materials and very large single parts cannot be manufactured today (especially not locally). Additionally, post-processing is considered mandatory for high-quality design features.
# 3D Reconstruction of a Single Bubble in Transparent Media Using Three Orthographic Digital Images
## 2 Experimental Apparatus and Visualization  
### Experimental Set-Up  
The schematic of the image acquisition device is illustrated in Figure 1. Laponite RD transparent soil [28] was used as the supporting medium to maintain the suspension of a single bubble in the center of an acrylic box, the size of which was \(100\times 100\times 150\) mm\({}^{3}\). Three digital cameras (BaumerVCXG-13M), all connected to a computer, were utilized simultaneously for the front view, side view, and top view. Each camera had a matrix of \(1024\times 1280\) pixels and the size of the pixel was 0.0048 mm. The diameter of sparger was 1 mm. The distance between the front view camera and the center of the box was 463.0 mm, while the distance between the side view camera and the center of the box was 439.0 mm. Since the distance were much larger than experimental bubble diameter (less than 20 mm). Therefore, the distortion caused by light refraction between transparent soil and acrylic as well as the light refraction between acrylic and air was negligible. Two LED panels were placed behind the acrylic box to ensure sufficient illumination, which could reduce the significant errors in the bubble size measurement. Since the wall influence, which caused bubble asymmetry was uniform in cuboid acrylic box, the front view was similar to the side view and the top view resembled being circular.