esa-sceva/satcom-chunk-collection huggingface dataset:
# Design and Functionality of a Prototype for Cold Needle Perforation of Wheat
## 2 Materials and Methods
### Cold Needle Perforation Pilot-Scale Prototype  
A cold needle perforation (CNP) prototype was built in-house. The wheat kernel application is done automatically to increase dosage reproducibility and distribute the wheat kernels on the conveyor belt. It consists of a hopper (Retsch GmbH, DR100, Haan, Germany) and a 270 mm long 3D-printed chute (Extrudr I FD3D, GreenTEC, Lauterach, Austria). The conveyor belt is made from food-grade thermoplastic polyurethane (Habasi GmbH, FMW-3 EZWH-P1, Eppertshausen, Germany), cushioned by a polytetrafluoroethylene-covered sponge (Hans Werner GmbH, product number 129.33 (\(280\,\mathrm{mm}\times 140\,\mathrm{mm}\times 20\,\mathrm{mm}\)), Laupheim, Germany), is powered by a worm-geared motor (Vector Aandrijftechniek B.V., V380-415Y, Rotterdam, The Netherlands) and its speed is controlled by a single-phase frequency converter (ABB Ltd., ACS 141-K37-1, Zurich, Switzerland). The perforation in the CNP prototype is achieved by a roll of 3'120 1.8 mm long needles consisting of 65 circular saw blades (Bosch GmbH, Dremel saw blade 546, Farmington Hills, MI, USA) separated by 1 mm thick 3D-printed polylactic acid (PLA) discs (Redline Filament GmbH, PLA filament RAL 7011, Neuss, Germany). To avoid breakage of the perforation unit, a saw tooth geometry with increased stability was chosen. This perforation unit is attached to a speed- and height-adjustable axis. Through the height adjustment via a fine pitch spindle and two guiding bolts, the gap size is set to either \(-1\) mm or \(0\) mm, thus creating different pressure levels on the kernels during perforation. Different shear forces can be imposed on the kernels through the speed adjustment via an adjustable voltage source (BaSeTech Batterie Service GmbH, BT-3010, Hamburg, Germany) of the motor (EPH Elektronik GmbH, DO11190393B00/3019, Besingheim-Ottmarskeim, Germany). The conveyor belt and feeder speed were adjusted to a throughput of 6 kg/h, and the kernels where perforated for 1, 5, or 10 cycles. A schematic drawing and an image of the CNP prototype are shown in Figure 1.  
Figure 1: Schematic drawing (**a**) and image (**b**) of the cold needle perforation (CNP) prototype, including a close-up view of the perforation unit (red).
## 5 Results  
In this paper, we test the performance of the DMP-TA algorithm through extensive simulation experiments and compare it with the CP-TM algorithm proposed in the literature [17]. The models and algorithms used in the experiments are implemented on an Intel(R) Core(TM) i7-9750H 2.59 GHz CPU and a computer with 8 GB RAM. The selected comparison algorithm, the CP-TM algorithm, is also a time complexity of \(O\left(n^{3}\right)\). This algorithm only considers aggregation between tasks that have an ordinary time window under the same satellite resource and the ordinary time window is larger than the required execution time of the task in the process of aggregation and prioritizes the merging of the two aggregated tasks with the most common time windows in each aggregation process.
# Autonomous Prostate Segmentation in 2D B-Mode Ultrasound Images
## 1 Introduction
### Contributions and Outline  
The proposed prostate segmentation algorithm within this paper specifically provides the three following contributions:  
* It incorporates a novel superpixel-based pixel clustering algorithm that includes a secondary graph-based hierarchy to allow for graph-cut image segmentation at the superpixel level.
* A probabilistic prostate model is introduced, and through the use of this probabilistic modeling, the algorithm is highly flexible and can produce contours which statistically resemble the input manual contours from a particular clinician or group of clinicians.  
Figure 1: Overview of prostate segmentation algorithm.  
* The prostate contouring algorithm is fully autonomous, and does not require any user input for the segmentation process, nor any manual post-algorithm contour correction.  
This paper is laid out as follows. A brief overview of the literature is provided in Section 2. The prostate contour model and statistical prostate shape model are presented in Section 3. The proposed superpixel algorithm for the ultrasound image processing is covered in Section 4 and the graph cutting segmentation is discussed in Section 5. The experimental setup and evaluation of the proposed algorithm as applied to in vivo patient images are given in Section 6. The conclusions and results are summarized in Section 7.
# Research on Low Energy Consumption Static Postures of Bionic Feet
## 5 Static Postures Analysis Considering Energy Consumption and Maximum Step Size
### Given the Yaw Angle \(\alpha\), the Foot Tip Falls in the Middle of the Maximum Step Size
#### 5.3.2 Simulations  
By adding the maximum step size, the influence of the energy consumption model and the maximum step size on the static posture under different values was considered. We set the yaw angle \(\alpha\;=\;30^{\lx@math@degree}\). According to the constraint of the maximum step size, the values of the joint angles \(\theta_{1}\), \(\theta_{2}\), and \(\theta_{3}\) of the body (when the output torque of the single leg is minimum) under different \(H\) were obtained, and are shown in Figures 10 and 11. The corresponding minimum joint output total torque \(M\) values are shown in Figure 12.  
Figure 9: Limit posture of the foot tip position.  
When \(\alpha=30^{\circ}\), it can be seen from Figures 10-12 that point C had the lowest energy consumption, and the low energy consumption static posture of the hexapod robot was  
\[\text{H}=90.0\ [\text{mm}],\ \theta_{1}=30^{\circ},\ \theta_{2}=45.4^{\circ},\ \theta_{3}=-135.4^{\circ}.\]  
Figure 11: Relationship between joint angles \(\theta_{1}\) and \(\theta_{2}\) under different values of \(\theta_{3}\).  
Figure 12: Minimum of \(M\) under different center of gravity heights.  
Figure 10: Joint angle \(\theta_{2}\) and \(\theta_{3}\) when \(M\) is minimum under different center of gravity heights.  
It can be seen from the simulation results that under the condition of considering the energy consumption target, the total output torque of the joint in the static posture was the smallest. Moreover, the static energy obtained by the method was comprehensively considered under the condition of energy consumption and maximum step size. Since the solution obtained by considering the energy consumption and the maximum step size target was the equilibrium solution, the total output torque was low. This thus verified the correctness of the proposed method.  
The same method could be used to obtain low-energy static postures of the robot under different values, as shown in Table 5.
# Identifying the Initial Corrosion Fatigue Failure Based on Dropping Electrochemical Potential
## 3 Results and Discussion  
### Evaluation of the Electrode  
In the electrochemical experiments, a titanium/titanium-mixed oxide electrode was used to maintain a constant potential within the corrosion chamber, without making electrical contact with the specimen or chamber. A custom-built Ag/AgCl electrode served as the reference, designed for direct measurements near the specimen. This self-manufactured Ag/AgCl electrode, modeled after a standard version, offered increased durability and shock resistance, making it particularly effective for use under cyclic loads. Its design also allowed for reliable operation under high temperatures and severe vibrations, making it well suited for demanding conditions.  
To evaluate this Ag/AgCl wire electrode, the electric potential was compared to the potential of a standardized Ag/AgCl glass electrode under experimental boundary conditions. The standardized glass electrode is well known for its design simplicity, repeatability,  
Figure 3: Schematic setup of the in situ corrosion fatigue testing procedure and electrochemical data collection. The setup with respect to different aspects has been used and described earlier [19; 20].  
and stable electric potential that allow trustworthy evaluation of the unknown electrodes and has been introduced in detail earlier [6; 26]. The electric potential values obtained were then aligned to the potential value of the standard hydrogen electrode (SHE) for conformity reasons. Applying the standard deviation to values measured, the electric potential of the Ag/AgCl wire electrode was calculated as follows: U\({}_{\text{SHE}}\) = 120-177 mV = -57 (\(\pm\)1.1 mV). The electric potential of the standardized glass Ag/AgCl electrode at elevated temperatures was obtained from [27]. The graphic representation of the calculation is shown in Figure 4 demonstrating the electric potential of the Ag/AgCl wire electrode in relation to the SHE; the value of the Ag/AgCl glass electrode was adopted from [27]. The setup is shown below.
## 4 Impossibility Results
### Distributed Graph Problems
#### 4.2.3 All-All Shortest Paths Construction (AASP)  
The AASP problem is specified as follows.  
* **Safety specification of AASP** states that for each node of a graph acting as a source (or sink) node, (the spanning tree representing) the shortest paths to (or from) every other node are selected.
* **Liveness specification of AASP** states that each process should eventually be able to detect that the construction of the shortest paths spanning tree rooted at itself is completed.  
**Theorem 10**: _In a system with even one Byzantine process, the distributed AASP construction problem is subject to the same limitations (exposure to false positives and false negatives) as the CD problem, resulting in safety and liveness violations._  
Solving AASP requires satisfying  
\[(\forall i)\Phi_{AASP}(e_{i}^{\hat{y}^{i}})\overset{def}{=}\bigwedge_{i}( \bigwedge_{h}(e_{h}^{x_{h}^{i}}\to e_{i}^{y_{h}^{i}}|_{E}=e_{h}^{x_{h}^{i}} \to e_{i}^{y_{h}^{i}}|_{F}=1)),\]  
where \(e_{h}^{x_{h}^{i}}\) is an event where \(p_{h}\) has identified its adjacent edges in a shortest paths sink tree rooted at \(p_{i}\) (of an actual shortest path sink tree of \(p_{i}\)), \((\forall h)\,y_{h}^{i}\leq\hat{y}^{i}\), \(e_{i}^{\hat{y}^{i}}\) is an event where \(p_{i}\) determines that the distributed determination of the shortest path sink tree rooted at itself is complete, and \(\rightarrow\) is defined on the shortest path sink tree algorithm messages.  
As \(e_{h}^{x_{h}^{i}}\) is an internal event, from Theorem 1 for the CD problem, detecting \(e_{h}^{x_{h}^{i}}\to e_{i}^{y_{h}^{i}}\) is susceptible to false positives and false negatives. Thus, it cannot be guaranteed that for any \(i\), the predicate \(e_{h}^{x_{h}^{i}}\to e_{i}^{y_{h}^{i}}|_{E}=e_{h}^{x_{h}^{i}}\to e_{i}^{y_{h }^{i}}|_{F}\) in the formula \(\Phi_{AASP}\) can be satisfied. Hence, AASP cannot be solved.  
A false positive of the CD problem is a safety violation--a shortest paths sink tree is not used as the sink tree rooted at some \(p_{i}\)--in the AASP problem. A false negative of the CD problem is a liveness violation--completion of the construction of the shortest paths sink tree rooted at some \(p_{i}\) is not detectable by that \(p_{i}\)--in the AASP problem.
# Anti-Collision System for Small Civil Aircraft
## 3 Design of the Anti-Collision System for the Category of Small Aircraft  
Based on the conducted analysis of the accessible methods of flying objects position identification, the conclusion is that the distance measuring method would be the most appropriate for the design of the architecture of an anti-collision system for small civil aircraft. We assume that the proposed system will operate in the communication network of aviation. The European Commission's directive maintains that the category of small aircraft up to 5700 kg do not have to be equipped with a certified anti-collision system ACAS II. Implementation of the offered versions of these systems onboard aircraft involves significant financial expenses. On the other hand, their absence has a direct influence on the safety of air traffic operations. The aim is to design an appropriate equivalent of the currently employed anti-collision systems which will be usable for the category of small aircraft.
## 3 Results and Discussion
### Pearson's Correlation Analysis  
We used Pearson's correlation analysis to assess the similarity of the \({}^{238}\)U, \({}^{232}\)Th and \({}^{40}\)K specific activity concentrations and their related radiological parameters (Raeq, DR, Hex and RLI) in the soils from the Lisava uranium mining area. Pearson's correlation coefficients classify the linear relationship between all variables by the confidence intervals of the coefficients as follows: weak (0.00-0.19), moderate (0.2-0.39), strong (0.4-0.79) and very strong (0.8-1.00) [35; 36]. The Pearson's correlation coefficients from this study are displayed in Table 4.  
Figure 8: Ra\({}_{\rm eq}\) and DR calculated for all soil samples from Lisava uranium mining sector.  
Figure 9: Ra\({}_{\rm eq}\) and DR (Hex) values calculated for all soil samples from Lisava uranium mining sector.  
\({}^{238}\)U showed a very strong correlation with Raeq and Hex, a strong correlation with RLI and a moderate correlation with \({}^{40}\)K and DR. \({}^{232}\)Th exhibited negative correlations with almost all the variables with the exception of \({}^{40}\)K. \({}^{40}\)K presented a weak to moderate correlation with all the detected variables. The very strong correlation between \({}^{238}\)U and the radiological hazard indices suggested that uranium was the dominant contributor to the radiological hazard and risks assigned to gamma rays emitted from the \({}^{238}\)U decay series in the soil. In addition, the negative correlation between \({}^{238}\)U and \({}^{232}\)Th and the weak correlation with \({}^{40}\)K reflected the impact of uranium mining on the increased radiation levels and radiological risk in the study area.  
The negative correlation between uranium and thorium implied a different origin of the two elements. Thus, the main sources of uranium were accessory minerals enriched in U but not Th. Part of the observed U values were due to the leaching of U-bearing phases that incorporated large amount of uranium, whereas the rest was attributed to contamination resulting from uranium mining activities [37]. The positive correlation between potassium, uranium and thorium, although moderate and weak, revealed that both the radionuclides were derived from natural sources. Potassium is a common element in sedimentary rocks with an increased content in K-felspar, mica and clay minerals.
## 6 Experiments and Results  
### Continuity Performance Test  
A physical prototype of the designed conductive center pole was made, as shown in Figure 21. Since it only needs to verify the action and conduction performance of the key structure of the conductive module, on the basis of retaining the key features and dimensions of the center pole, it has been reduced in the length direction. The lengths of the two test center poles are 200 mm and 133 mm, respectively, and the connection between the center poles is an annulus with a diameter of 20 mm and an M30 threaded connection.  
The resistance of the connected conductive center pole was measured using a multi-meter, as shown in Figure 22.  
It was measured that one end of the connection resistance was 0.3 \(\Omega\), and the other end was 0 \(\Omega\), and its conduction performance was good. The electrothermal conversion efficiency of the center pole conductive module in actual use still needs further experimental verification.
# UAV-Based Privacy-Preserved Trustworthy Seamless Service Agility for NextG Cellular Networks
## 5 Experiment Evaluation
### Equipment List  
The experiment is conducted using a server having 4 CPUs, Intel(R) Core(TM) i7-7700K 4.2 GHZ. The PC is connected with 4 Universal Software Radio Peripherals (USRPs) and runs VMWare Esxi server hosting 3 Virtual Machines (VMs) as follows,  
* UAV VM: The UAV virtual machine with 8 cores and 8 GB of RAM is connected to 2 USRP, B205 mini. The first B205 mini USRP runs an srsENB module that accepts connections from home network UEs and provides them with the guest eNB info to port through. Moreover, the second B205 mini USRP runs an srsUE module to communicate with the guest eNBs and facilitate the service port. The VM also runs the home core using the srsEPC module.
* UE VM: The UE virtual machine with 8 cores and 8 GB of RAM is connected to a B205 mini USRP running our modified version of the srsUE module that supports our proposed extra mode of operation. The extra mode of operation represents the proposed delegation phase in addition to the standard connection procedure.
* Guest eNB VM: An eNB virtual machine similar to the UE VM, 8 cores and 8 GB of RAM, is also connected to a B205 mini USRP running our modified version of the srsENB module, which accepts additional external connections to support accommodation and porting requests.  
We set the UAV B205 mini USRP to change roles or functionality as needed and perform as both srsUE and srsENB. Hence, the UAV is able to execute the mutual authentication process. In particular, the UAV will serve as an srsENB while authenticating the UE and sending the guest eNB info and connection token to the UE. Then the UAV change roles to perform as an srsUE to accommodation request to the guest eNB. Since the two modes of operation, srsUE and srsENB, are not running simultaneously, the most suitable inter-process communication technique is a shared file as a producer-consumer queue. Running separate processes for the srsUE and the srsENB sockets connection can offer the advantages of bi-directional communication but with more significant overhead. However, the extra overhead can be tolerated as the two processes run on two different virtual machines. The experiment setup is shown in Figure 4.
## 2 Multi-Hop Bent-Pipe LEO Satellite Constellation  
Benefiting from optical ISL, low latency, and low-noise optical switching via wavelength multiplexing(WDM) technology, optically transparent transmission channels can be established between satellites, which can be used to eliminate the expensive regeneration and packet processing resources. Furthermore, the satellite internet system can use the large aperture antenna of the gateway station to compensate for the deterioration of the SNR.  
To improve the flexibility of optical satellite networks, the proven WDM technology on the optical networks can be introduced very effectively to create multiple optical path channels in the ISL [33]. As shown in Figure 2, after a flow is transmitted toward the satellite through the uplink channel, it will be modulated into the optical signal of a specific wavelength, and forwarded by the optical switch according to the two-tuple entry (ingress port, wavelength) recorded in the onboard forwarding table. Finally, the flow can be forwarded to the destination in a multi-hop manner.  
Figure 1: Low-orbiting satellite network employs inter-satellite laser communication and optically controlled millimeter wave-phased array. Wavelength multiplexing between constellations is used to transfer data from users in different cells. The wavelength multiplexing can be directly converted into the corresponding millimeter wave-beam pointing by unique characteristics of the array waveguide grating router structure.  
Figure 2: Wavelength Assignment and Routing.
# Image Segmentation Approaches for Weld Pool Monitoring during Robotic Arc Welding
## 3 State of the Art Methods for Laser Line Segmentation  
### Top-Hat Transform Based Method  
In Reference [19], the uneven background caused by the arc light was removed by the top-hat transform, which is formulated as [24]:  
\[T(f)=f-f\cdot e, \tag{1}\]  
where \(\cdot\) denotes the opening operation, \(f\) denotes the image and \(e\) denotes the structuring element. \(e\) is chosen as a disk with radius 15 in this research work. After the image was enhanced by the top-hat transform, the image was segmented by the threshold selection method. The selected welding parameters are as follows. The wire feed speed is 55 mm/s, the welding speed is 5 mm/s, the peak current is 220 A and the base current is 50 A. As a result, the captured image is very clear for segmentation. However, their segmentation result still misses significant parts for the laser lines.
###### Abstract  
The accuracy of 3D viewpoint and shape estimation from 2D images has been greatly improved by machine learning, especially deep learning technology such as the convolution neural network (CNN). However, current methods are always valid only for one specific category and have exhibited poor performance when generalized to other categories, which means that multiple detectors or networks are needed for multi-class object image cases. In this paper, we propose a method with strong generalization ability, which incorporates only one CNN with deformable model matching processing for the 3D viewpoint and the shape estimation of multi-class object image cases. The CNN is utilized to detect keypoints of the potential object from the image, while a deformable model matching stage is designed to conduct 3D wireframe modeling and viewpoint estimation simultaneously with the support of the detected keypoints. Besides, parameter estimation by deformable model matching processing has robust fault-tolerance to the keypoint detection results containing mistaken keypoints. The proposed method is evaluated on Pascal3D+ dataset. Experiments show that the proposed method performs well in both parameter estimation accuracy and the multi-class objects generalization. This research is a useful exploration to extend the generalization of deep learning in specific tasks.  
3D vision; viewpoint estimation; wireframe modeling; deformable model +
Footnote †: journal: Applied Soft. 2019, 9, 1975; doi:10.3390/app9101975
## 3 Results and Discussions
### The Influence of Temperature on Battery Performance
The average charging capacity of six cycles is 1022.6, 1034.9, 1031.6, and 1034.5 mAh, and the average discharging capacity is 1026.8, 1035.9, 1030.4, and 1032.1 mAh, under the extreme conditions, natural convection, PCM cooling, and PCMcombined with heat dissipation fins working condition, respectively. The LIB capacity changes are related to the temperature. The battery capacity does not change significantly, which indicated that the LIB capacity is not significantly affected by short cycles even at high temperatures. Compared with the natural convection condition, the LIB discharging capacity under PCM cooling and PCM combined with heat dissipation fins decreased slightly. In the case of higher temperature, the battery reaches the cut-off voltage more slowly during the charging and discharging process, and the constant current charging and discharging time is longer, so the charging and discharging efficiency is higher, and the maximum capacity value is larger. However, the high temperature has a great influence on the capacity degradation rate of LIB [40]. The higher temperature leads to a quicker rate of various side reactions in the battery and faster the capacity degradation. Due to the low number of battery cycles in the experiments, the internal damage or possible side reactions that might have occurred at high temperatures had not yet become apparent. In the current application of LIB with the high efficiency and capacity, reducing the impact of itself side reaction and temperature are particularly critical, which is also a hurdle for the current LIB technology breakthrough.