esa-sceva/satcom-chunk-collection huggingface dataset:
# A Framework for Bluetooth-Based Real-Time Audio Data Acquisition in Mobile Robotics
## 7 Applications and Future Directions  
### Potential Applications  
Security and surveillance: The combination of mobility and audio sensing creates new possibilities for security applications, where the rover can investigate suspicious sounds or provide audio monitoring of areas that lack fixed infrastructure [15]. The relatively quiet operation of the platform makes it suitable for unobtrusive monitoring in sensitive environments. This application aligns with work by [PERSON] et al. [37] on bomb identification and defusing robots, demonstrating the potential for specialized security applications.  
STEM education: The accessible design using commercial components makes the platform an excellent teaching tool for interdisciplinary STEM education, integrating concepts from robotics, digital signal processing, wireless communication, and software development. Students can modify and extend the platform to explore various aspects of these domains while working with tangible, engaging technology, building on [PERSON]'s work [13] in MEMS-embedded system design.  
Acoustic research: For researchers studying environmental acoustics, the platform offers a cost-effective tool for gathering spatially diverse audio samples without the logistical challenges of deploying multiple fixed recording stations. The mobility enables adaptive sampling strategies based on real-time assessments of acoustic phenomena, supporting work like that of [PERSON] et al. [41] on emotion sensing using mobile devices.  
Assistive technology: With modifications to enhance audio sensitivity in specific frequency ranges, the platform could serve as an assistive device for individuals with hearing impairments, allowing for the remote investigation of sounds or alerting users to specific acoustic events in their environment [27; 28].
# Efficient Resource Allocation for Beam-Hopping-Based Multi-Satellite Communication Systems
## 6 Conclusions  
In this paper, we formulated a resource-allocation problem in the multi-satellite system and investigated two algorithms based on beam-hopping technology. Firstly, a multi-satellite offline resource-allocation algorithm based on beam-hopping technology was  
Figure 4: Single-beam throughput performance.  
Figure 3: System throughput of proposed algorithms.  
proposed to address the satellite resource limitation problem and improve the efficiency of resource utilization. A heuristic time-frequency resource-allocation algorithm was proposed based on the beam interference pattern, and the power resources were allocated using the SCA algorithm. However, it was assumed that future channel information should be obtained in advance in the offline resource allocation algorithm, which is difficult to achieve in the real world. Therefore, we proposed a dynamic programming algorithm to design a multi-satellite online resource allocation algorithm that only relies on instant channel information.  
The final simulation results demonstrate that, compared with traditional average resource-allocation methods, our proposed offline algorithm improves system throughput by about 60% to 65%, and the online algorithm improves system throughput by about 45% to 50%. Since the online algorithm only relies on instant channel information for resource allocation and uses discrete power values, there is a certain performance loss compared with the offline algorithm, but the results show that this loss is acceptable.  
The algorithm proposed in this paper is only tested in the scenario consisting of three satellites. The computation complexity of the proposed algorithm may increase sharply with the number of satellites and whether the algorithm complexity can be tolerant should be tested in the real satellite communication system.  
Methodology, Y.W.; Writing--original draft, Y.W.; Writing--review & editing, M.Z.; Funding acquisition, M.Z. and Z.F. All authors have read and agreed to the published version of the manuscript.  
This work was supported by National Key R&D Program of China under grant 2020 YFB1806000.  
The data and code are available from the corresponding authors upon reasonable request.  
The authors declare no conflict of interest.
## 3 Preliminaries
### Physical Unclonable Function  
A PUF is a physical circuit that generates a distinct output for each input based on variations in the microstructure of the hardware [41; 42]. The PUF operates through the sensor's intrinsic response and can generate keys without requiring any external hardware modules. In addition, unlike biometric-based systems, PUF responses are not affected by user behavior or environmental noise, and they produce consistent outputs under identical conditions. The PUF derives secrets from the physical characteristics of the integrated circuit. In contrast to traditional secret key storage methods, the PUF does not require storing secret keys; instead, it produces unique input-output pairs, known as \"challenge-response\" pairs. This paper describes the PUF operation as \(RE=PUF(CH)\), where \(RE\) represents the corresponding response and \(CH\) denotes the challenge. The properties of the PUF are described below:  
* A PUF generates a unique response for each challenge.
* The physical structure of a PUF cannot be cloned.
* The response of a PUF is unpredictable and depends on physical circuits.  
The PUF-based scheme is simple and requires minimal computational overhead. A PUF generates a unique fingerprint of the sensor without requiring additional hardware. Since the PUF module is inherently embedded in the IoT sensor, it offers a lightweight security mechanism without memory resources. These characteristics make it particularly suitable for IoT-based environments [43]. Therefore, we propose an authentication scheme utilizing PUF for IoT-based smart farming environments.
# A Review on Optoelectrokinetics-Based Manipulation and Fabrication of Micro/Nanomaterials
## 1 Introduction
These forces are further exerted onto the micro/nanoparticles, driving, directing, and delivering them towards the intended destination programmatically and digitally. This is how optical-electrokinetics-microfluidics integration works. Featuring the use of optically-projected images as virtual electrodes to directly manipulate micro/nanoparticles and without referring to metal-based electrodes, OEK has been widely used in the manipulation, separation, assembly, and fabrication of micro/nano-entities as well as extraction of their intrinsic properties [33; 34; 35; 36; 37; 38], which has shown a highly promising new strategy in the development of micro/nanomanipulation and fabrication communities. More recently, Berkeley Lights Inc., the inventor of OEK, has commercialized this technology in bio-related fields, offering a unique approach to take the development of biomedical and bioengineering sciences to a new level. Furthermore, it also shows the high potential for the use of this technology in material manipulation and fabrication to move from lab-oriented research to real-world applications. Unlike previous review studies that only discuss some aspects of OEK-based microfluidics [39; 40; 41], we present a comprehensive review of OEK-based manipulation and fabrication of micro/nanoparticles. First, we summarize differently structured OEK chips and discuss their respective working principles. Then, we describe OEK-based manipulation and fabrication of micro-/nano-scaled materials without using any masks. Next, we review the use of OEK chips for fabricating various hydrogel-based structures and functional micro/nanodevices. Finally, we explain current and future challenges facing the OEK technique and possible innovations on it.
# Hg Content in EU and Non-EU Processed Meat and Fish Foods
## 3 Results
### Results
\begin{table}
\begin{tabular}{c c c c} \hline \hline  & & \multicolumn{2}{c}{**Hg**} \\ \hline
**Samples** & **No Samples** & \(\text{\mu g}/\text{Kg}\) & **TWI\%** \\ \hline  & & **Range** & **Range** \\  & & **Min–Max** & **Min–Max** \\ \hline Canned tuna & 17 & 9.25–290.21 & 4.63–145.11 \\ Natural and dried shrimp & 7 & 9.45–11.90 & 4.73–5.95 \\ Canned sardines & 3 & 13.89–14.21 & 6.95–7.11 \\ Canned crab meat & 3 & 8.07–11.30 & 4.03–5.65 \\ Canned pink salmon & 2 & 10.15–15.19 & 5.08–7.59 \\ Dried sardines & 3 & 98.34–101.08 & 49.17–50.54 \\ Canned mackerel fillets & 4 & 24.84–27.33 & 12.42–13.67 \\ Canned horse mackerel & 3 & 26.62–37.96 & 13.31–18.98 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Tolerable weekly intake (TWI) % values for Hg contents in analyzed processed fish and shellfish.
## 4 Results and Discussion
### Theoretical Remarks
Based on the four equation water hammer model, primary wave (i.e., fluid pressure wave) speed is given by ([4]):  
\[c_{f}=\sqrt{\frac{1}{2}(\beta^{2}-\sqrt{\beta^{4}-4c_{w1}^{2}c_{L}^{2}})}, \tag{3}\]  
where \(\beta\) is a constant introduced for the sake of readability:  
\[\beta^{2}=(1+2\
u^{2}\frac{\rho_{f}}{\rho_{s}}\frac{R}{e}\frac{1}{1+\frac{e}{ 2R}})c_{w1}^{2}+c_{L}^{2}, \tag{4}\]  
where \(c_{w1}\) is the sound speed in a fluid contained in an elastic pipe and the sound speed in an incompressible fluid contained in an elastic pipe \(c_{w0b}\) (\(c_{w1}\), defined in Equation (5), does not include the effects of pipe vibrations on the wave speed in the inner fluid, contrary to\(c_{f}\), as defined in Equation (3), and only takes in account the pipe wall stretching due to the pressure load). In [22], its value is deduced from the sound speed in the unrestrained fluid (\(c_{w0}\), which is defined in Equation (2)). \(c_{w1}\) is defined as:  
\[c_{w1}=\frac{c_{w0}\ c_{w0b}}{\sqrt{c_{w0}^{2}+c_{w0b}^{2}}}, \tag{5}\]  
with \(c_{w0b}=\sqrt{\frac{E\ c}{2R\ \rho_{f}}}\). \(c_{L}\) is the longitudinal wave velocity in a bar:  
\[c_{L}=\sqrt{E/\rho_{s}}. \tag{6}\]  
Finally, with water properties given in Table 2, \(R=\ 7\) A.U.L. and \(e=7.5\) A.U.L. (which are the dimensions of the channel tube), we obtain: \(c_{f}=1062\ \mathrm{m}\cdot\mathrm{s}^{-1}\). The theoretical velocity of precursor waves is defined by:  
\[c_{s}=\sqrt{\frac{1}{2}(\beta^{2}+\sqrt{\beta^{4}-4c_{w1}^{2}c_{L}^{2}})}. \tag{7}\]  
With the material properties given in Table 1 and dimensions mentioned above, it yields \(c_{s}=3160\ \mathrm{m}\cdot\mathrm{s}^{-1}\). \(c_{s}\) is close to the typical longitudinal wave velocity in Zircaloy-4 (\(c_{Zr4}=\sqrt{\frac{E_{Zr4}}{P_{Zr4}}}=\sqrt{\frac{28\times 10^{6}}{6560}}=3448 \ \mathrm{m}\cdot\mathrm{s}^{-1}\)). It is actually the typical longitudinal wave velocity with light modification due to the Poisson effect and the fluid-structure interaction. In that preliminary study, only a simple pipe representing the outer tube was considered, rather than two coaxial tubes, which would better represent the complete system. However, the objective was simply to get approximated velocities to guide the interpretation of numerical and experimental results. Thus, it was considered that the necessary work to accurately adapt the four-equation water-hammer model to the studied case was not relevant in the frame of this study.
## 4 Model and Notations
### Mixed-Integer Linear Programming
#### 4.1.2 Modeling Calendar Constraints  
The start-based model is further extended to solve unavailability problems, which are also addressed by incorporating resource calendar constraints. The processing of a job should not start during the time window of unavailability of resource \(k\). That is to say that any operation must be carried out and finished before the arrival of an interval of unavailability. The execution time of an operation must be outside unavailability interval.  
\[\left[S_{ijk},S_{ijk}+P_{ijk}\right]\cap\left[v_{k}^{l},v_{k}^{l}\right]=\varnothing \tag{17}\]  
Constraint (18) allows to calculate the total unavailability period of a machine k that processes job \(i\).  
\[u_{i}=\sum_{k=}^{m}\sum_{l}^{l_{k}}X_{ik}(\overline{v}_{k}^{l}-v_{k}^{l}) \tag{18}\]  
Constraint (19) calculates the operations completion time  
\[C_{ijk}=P_{ijk}+S_{ijk}+S_{ijk}+S_{ijk}+u_{i},\forall i\in N,j\in J_{i},k\in m _{j} \tag{19}\]  
Now, we have:  
\[C_{i}=\sum_{k=1}^{mi}P_{ijk}+S_{ijk}+S_{ijk}+S_{ijk}+u_{i},\forall i\in N \tag{20}\]  
From now on, we refer to the model that incorporates resource calendar constraints into model \(\mathrm{MILP_{wav}}\), \(\mathrm{MILP_{RC}}\).
# Survey on Unmanned Aerial Vehicle for Mars Exploration: Deployment Use Case
## 4 Simulation Results and Discussion
### Environmental Conditions
#### 4.1.4 Air Temperature  
Air temperature plays a vital part in the behaviour of the flight of UAVs. The lift generated by a UAV depends mainly on the air density. Air density depends on the air temperature and altitude. At higher temperatures, air density is reduced. As a result, a UAV will have to travel faster to generate enough lift for take-off. The air temperature at Mars is 210 K (approximately).
## 2 Description of the Power Converter System Solution for a Cogenerator with an Induction Machine  
A block diagram of the power supply system with an induction generator and a set of power converters is shown in Figure 1.  
The characteristic feature of the system is the use of two AC-DC power converters (power grid PC2 and generator PC1) and one DC-DC battery converter with a dual-active-bridge (DAB) structure (PC3.1). In addition, a DC-DC buck-boost converter (PC3.2) was installed. PC3.2 discharges excess electricity when the battery voltage and current limits are reached during charging. The voltage of the DC bus between the converters is approx. 710 V. The nominal voltage of the battery is 48 V. The selected value of the battery voltage is due to practical reasons. The device will be operated by persons without appropriate qualifications to work on electrical installations. However, the user should be able to safely disconnect and reconnect the battery during routine service work. In on-grid mode, the DC bus voltage is stabilized by the PC2 grid converter, and the battery and PC3.1 and PC3.2 converters are not used. In the off-grid mode, the voltage on the DC bus is stabilized by the PC3.1 and PC3.2 power converters.  
Assumed functional features of the power supply system with CHP:  
* in on-grid and off-grid modes, power regulation at the grid connection point (on-grid) or load (off-grid) is carried out by changing the rotational speed of the induction generator (forced by the frequency of the voltage generated by the PC1 converter), controlling the dose of fuel (ICE) and the power of the electric energy storage;
* in on-grid and off-grid modes, the rotational speed of the induction machine can be changed within the permissible range, independent of the fixed voltage frequency in the power system. The rotational speed of the induction generator can be set by a generator converter, PC1. Then, the drive works with torque control (as it does in an internal combustion engine, by controlling the fuel dose);
* the possibility of supplying unbalanced three-phase loads [50].
## 3 Test Results and Discussion
### Determination of Mineral Filler Content  
Based on the above test results, it is obviously that with the increasing content of the mineral fillers, the durability increases but the permeability decreases. Therefore, careful selection of the mineral filler content would be required to keep the balance of durability and functionality for the novel gradation PAC10 mixture. In Figure 6, it was shown that Cantabro loss of freeze-thaw Cantabro test after three cycle condition is maximum for all the test condition of this study, and Figure 7 shows that the vertical permeability coefficient is smaller than transverse permeability coefficient. The Cantabro loss of freeze-thaw Cantabro test after three cycle condition is used to represent the durability and the vertical permeability coefficient is used to represent the functionality. Figure 8 presents the interaction between durability and functionality of PAC10 mixtures with different mineral filler content.  
As shown in the Figure 8, increasing the mineral filler content from 4% to 6%, the Cantabro loss will decrease significantly, but further increase of mineral filler content to 8% has little effect on durability. At the same time, with the increasing content of the mineral fillers, the permeability coefficient decreases, and when increasing the content of the mineral filler from 6% to 8%, the permeability coefficient decreases more significantly than when increasing the content of the mineral filler from 4%  
Figure 8: Cantabro abrasion and permeability test results of PAC10 with different mineral filler content.  
Figure 7: Results of permeability tests.  
to 6%. Therefore, the novel PAC10 mixture containing 6% mineral filler can better balance durability and functionality, and 6% mineral filler is recommended for the novel gradation design.
## 3 Results
### Human Reliability Assessment for Activities with the Potential for Human Failure
\begin{table}
\begin{tabular}{c c c c c} \hline \hline  & **Process** & \multicolumn{3}{c}{**HEP**} \\ \hline
**Step** & **Activity Description** & **Responsibility** & **Secondary** & **Technical** & **Resulting HEP** \\ \hline
1 & Empty bottles check & 0.005 & 0.001 & 0.001 & 0.00000005 \\ \hline
2 & Checking the amount of solvent—acetone & 0.005 & 0.001 & 0.001 & 0.00000005 \\ \hline
3 & Reacetonation & 0.01 & 0.001 & 0.001 & 0.0000001 \\ \hline
4 & Connecting the bottles to filling points & 0.001 & 0.001 & 0.001 & 0.00000001 \\ \hline
5 & Checking the tightness of connections & 0.0021 & 0.001 & 0.001 & 0.000000021 \\ \hline
6 & To be recorded in the production record & 0.001 & 0.001 & 0.000000001 \\ \hline
7 & Securing bottles with fall-arrest chains & 0.005 & 0.001 & 0.001 & 0.00000005 \\ \hline
8 & Bottling & 0.001 & 0.001 & 0.001 & 0.00000001 \\ \hline
9 & During filling, the bottle cooling function and bottle temperature are checked & 0.005 & 0.001 & 0.001 & 0.00000005 \\ \hline
10 & Closing the filling valves at the acetylene inlet on the ramp & 0.001 & 0.001 & 0.001 & 0.00000001 \\ \hline
11 & When the compressors are switched off, the inlet valves on the ramps are closed & 0.001 & 0.001 & 0.001 & 0.00000001 \\ \hline
12 & Closing the bottles & 0.001 & 0.001 & 0.001 & 0.00000001 \\ \hline
13 & Opening the degassing valves & 0.001 & 0.001 & 0.001 & 0.00000001 \\ \hline
14 & Ramp degassing & 0.01 & 0.001 & 0.001 & 0.00000001 \\ \hline
15 & Degassing valves closing & 0.001 & 0.001 & 0.001 & 0.00000001 \\ \hline
16 & Bottle securing & 0.01 & 0.001 & 0.001 & 0.0000001 \\ \hline
17 & Tightness inspection & 0.005 & 0.001 & 0.001 & 0.000000005 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: HEP determination for acetylene bottling. \begin{table}
\begin{tabular}{c c c c} \hline \hline  & **Process** & \multicolumn{3}{c}{**Acetylene Bottling**} & **Date** \\ \hline
**Step** & **Activity Description** & **Responsibility** & **Co-Responsibility** & **Technical Inspection** \\ \hline  & \multicolumn{3}{c}{Acetylene bottles carrying away} \\ \hline
20 & Transport to the handling area & Transport platoon staff & Production technologist, operations master & \\ \hline
21 & Record in the production record & Transport platoon staff & Production technologist, operations master & Anti-flame insurance, Insurance caps \\ \hline
22 & Records of imported empty bottles, dispatched bottles and full bottles & Warehouse woman or foreman (production and dispatch management) & Production technologist, operations master & \\ \hline  & & & \\ \hline  & & & \\ \end{tabular}
\end{table} 
Table 1: _Cont._Based on the reliability assessment performed for acetylene bottling, it can be concluded that step 3 of bottle reacetonation and step 16 of bottle securing represent the most risky activities in terms of human reliability.
# A Watermarking Technique for Biomedical Images Using SMQT, Otsu, and Fuzzy C-Means
## 3 Proposed Model
### Segmentation  
Dividing the image into different sections based on similar traits is called segmentation. Segmentation divides an image into multiple parts, where each part has the same kind of data [16]. For embedding a watermark, image segmentation plays a vital role so that the watermark can be embedded into the correct segment. In the proposed model, we did this segmentation in two steps: the first step is the Otsu's threshold method and the second step is the K-means clustering method. These two steps are described in the Subsections 3.2.1 and 3.2.2.
## Rate Adaptive Based Resource Allocation with Proportional Fairness Constraints in OFDMA Systems  
**[PERSON], [PERSON], [PERSON] * and [PERSON]**  
School of Electronics and Information Engineering, Harbin Institute of Technology, 92 Xidazhi Street, Harbin 150001, China; E-Mails: [EMAIL_ADDRESS] (Z.Y.); [EMAIL_ADDRESS] (S.Z.); [EMAIL_ADDRESS] (B.M.)  
* Author to whom correspondence should be addressed; E-Mail: [EMAIL_ADDRESS]; Tel.: +86-451-8641-3506; Fax: +86-451-8640-3135.  
Academic Editor: [PERSON]  
_Received: 25 July 2015 / Accepted: 23 September 2015 / Published: 25 September 2015_  
**Abstract:** Orthogonal frequency division multiple access (OFDMA), which is widely used in the wireless sensor networks, allows different users to obtain different subcarriers according to their subchannel gains. Therefore, how to assign subcarriers and power to different users to achieve a high system sum rate is an important research area in OFDMA systems. In this paper, the focus of study is on the rate adaptive (RA) based resource allocation with proportional fairness constraints. Since the resource allocation is a NP-hard and non-convex optimization problem, a new efficient resource allocation algorithm ACO-SPA is proposed, which combines ant colony optimization (ACO) and suboptimal power allocation (SPA). To reduce the computational complexity, the optimization problem of resource allocation in OFDMA systems is separated into two steps. For the first one, the ant colony optimization algorithm is performed to solve the subcarrier allocation. Then, the suboptimal power allocation algorithm is developed with strict proportional fairness, and the algorithm is based on the principle that the sums of power and the reciprocal of channel-to-noise ratio for each user in different subchannels are equal. To support it, plenty of simulation results are presented. In contrast with root-finding and linear methods, the proposed method provides better performance in solving the proportional resource allocation problem in OFDMA systems.  
**Keywords:** orthogonal frequency division multiple access (OFDMA); wireless sensor networks; rate adaptive; resource allocation; ACO-SPA; proportional fairness