esa-sceva/satcom-chunk-collection huggingface dataset:
# Combining NMR Spectroscopy and Chemometrics to Monitor Structural Features of Crude Hep-arin
## 3 Discussion  
The major goals in the analysis of a large number of porcine crude heparins and a range of crude heparin from different animal or tissue sources were: (1) to establish reliable test methods to differentiate them at the crude stage of manufacturing; and (2) to propose a definition for crude heparins as a key intermediate in drug manufacturing. Similar tests can be used to assure the quality of the porcine heparin or bovine heparin API used clinically. Importantly, by checking heparin quality earlier in the supply chain, contaminated material can be prevented from reaching the active pharmaceutical ingredient purification processes, which are often performed under cGMP in U.S. based plants. Because the supply chain for heparin is complex and a global one, controlling the quality of this widely used drug, its intermediates, and starting materials (at least as early as the crude heparin warehouse) solely through cGMP inspection is insufficient and often impractical, in part due to the limited resources that the regulatory authorities have. Thus, there is a need to develop strong analytics and appropriate specifications for crude heparin to ensure the consistent high quality of the final heparin drug substance. For this reason, the tests and the data obtained by applying them will help assure the quality of heparin sodium and LMWH drug products by improving the quality of the entire global heparin supply chain.  
In this work, strong anion exchange HPLC (SAX-HPLC) and NMR spectroscopy coupled with chemometrics was demonstrated to be a feasible strategy to characterize crude heparin samples. The proton NMR and HPLC data clearly show that crude heparins vary in terms of glycosaminoglycan composition, amount of DNA/RNA, and other impurities. Proton spectra, when the samples were properly prepared, could be analyzed by PCA, grouping samples based on their composition (relative amount of dermatan, chondro, and heparin) or structural properties (degree of sulfation). The presence in the library of some samples that were almost free from galactosaminoglycans and DNA/RNA components suggests that some batches have undergone different levels of purification treatments consistent with the known differences in the way heparins are manufactured by different companies. Quantitative HSQC analysis, recently applied to determine the mono- and disaccharide composition of heparin and LMWH [10], can be extended to crude heparin, allowing an in-depth study of the structural features of samples. Particularly, the degree of sulfation can vary starting from 2.1 to 2.4, the latter value is typical of the purified porcine heparin. Notably, the group of samples that lacked dermatan and chondro also contained oxidized serine, suggesting that the products were treated with oxidizing agents, such as those typically used during the production of API. Overall, PCA and HSQC analyses were able to distinguish between crude heparins of different animal and organ sources and manufactured by different processes.
## 2 Materials and Methods
### Separation and Confirmation of Gibberellic Acid (GA3) by LC-MS Analysis  
To separate gibberellic acid (GA3) from the extracted solution, we used a Thermo Finnigan (Polaris Q) Ion Trap combined with a liquid chromatography-mass spectrometry (LC-MS) system. The analytical column was ZB-5 (30 m \(\times\) 0.25 mm i.d., Zebron). The mobile phase was acetonitrile with 0.1% formic acid at a flow rate of 0.5 mL/min. An amount of 20 \(\mu\)L of each solution containing the extracted GA3 was injected into the chromatograph and the absorption wavelength was detected at 195 nm.  
To confirm whether the substance obtained after LC of the extraction solution was GA3, the ionization MS spectrum was obtained using electrospray ionization (ESI) in negative ion mode and at 550 \({}^{\circ}\)C, with N2 gas to create a mist (nebulizer). The detection mode was multiple reaction monitoring (MRM) of selected ions in the first (Q1) and third (Q3) quadrupole filters.
## 5 Summary and Conclusions  
This article presents a method for solving a significant problem involving the lack of agreement of the coordinates of identical boundary points of neighboring areas, which appears in relation to the transformation of coordinates between different systems. This study involves the boundary points of neighboring mining areas located in Poland in the Upper Silesian Coal Basin region. The significance of this problem in relation to the safe development of post-mining areas is indicated.  
Based on the presented analyses, it can be stated that the authorial procedure proposed in this article, using the method of independent models, allows the obtainment of consistent coordinates of identical boundary points. In the presented case, differences of only 0.001 m were found, which result from the rounding up of significant figures. Its application in the presented example allowed the elimination of differences in the coordinates of identical boundary points of the order of even several meters.  
The procedure allows us to fulfill the condition of topological agreement and can also be successfully applied in the cases of transformation of coordinates of other neighboring areas. It should be noted that its application is determined by the total size of the area undergoing transformation. However, for a large area, the applied curvature of the Earth and the ellipsoid should be taken into account in the calculations. Therefore, the authors have also developed a similar procedure that takes into account the curvature of the Earth, based on the MIM. This procedure will be presented in a separate publication.  
Conceptualization, V.S.-S., M.Z. and M.P.; methodology, V.S.-S.; software, M.P.; validation, M.Z., V.S.-S. and M.P.; formal analysis, M.Z. and V.S.-S.; investigation, M.Z., V.S.-S. and M.P.; resources, M.Z.; data curation, M.Z.; writing--original draft preparation, M.Z.; writing--review and editing, V.S.-S. and M.Z.; visualization, M.Z. and M.P.; supervision, V.S.-S. and M.P.; project administration, V.S.-S.; funding acquisition, M.Z. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
The original contributions presented in this study are included in the article. Further inquiries can be directed to the corresponding author.  
The authors declare no conflicts of interest.  
The following abbreviations are used in this manuscript:  
EUR  
European Union  
RGW  
Rybnik Coal Area  
GOP  
Upper Silesian Industrial Region  
S-JTSK  
System of the Unified Trigonometrical Cadastral Network  
KUL  
Union of Lublin Mound-Lviv  
MIM  
method of independent models  
USCB  
Upper Silesian Coal Basin  
CL  
coal mine  
MA  
mining area  
GCP  
Ground Control Point
# Review of Advancement in Variable Valve Actuation of Internal Combustion Engines
## 1 Introduction  
With growing concerns on energy security and global warming, there are global efforts to develop more efficient vehicles with lower regulated emissions, including hybrid electrical vehicles, electrical vehicles, and fuel cell vehicles. Hybrid electrical vehicles became a significant part of vehicle production because of their overall efficiency, and they still pose a significant cost penalty, resulting in a stagnant market penetration of 3.2% and 2.7% in 2013 and 2018, respectively, in the United States (US), for example [1]. Electrical vehicles reached a market penetration of 1.3% in the US in 2018 [1], still limited by high cost and concerns on well-to-wheel CO\({}_{2}\) emissions, charging speed, driving range, battery safety, and battery recycling issues. Fuel cell vehicles offer truly low overall emissions with driving range and fueling time comparable to vehicles powered by internal combustion engines. Hydrogen [2], the favorable fuel for fuel cells, can be generated from diverse sources, including natural gas, nuclear, coal, and renewable sources such as solar, wind, biomass, hydro, and geothermal sources. The development of fuel cell vehicles [3] is still in its infancy because of issues in technology maturity, cost, and performance, with only a few thousands of pilot vehicles on the road worldwide.  
Internal combustion engines are believed to remain as a major part of vehicle powertrains in the foreseeable future, either standing alone or being part of highly electrified powertrains such as hybrid electrical vehicles, plug-in hybrid vehicles, and range extender vehicles, unless there is a major technology breakthrough in battery and/or fuel cell technology. For these reasons, it is imperative to continue advancement in more efficient and less polluting internal combustion engines.
# Routing in Mobile Wireless Sensor Networks: A Leader-Based Approach+
## 4 Evaluation
### Simulation Environment  
Castalia is a simulator based on OMNeT++ and commonly used for extracting performance metrics in WSNs [27].  
Regarding the hardware configuration for Castalia, every simulation has been configured using the CC2420 radio with 0 dBm of transmission power. Additionally, Castalia provides a parameter called PLd0, which models the know path loss at a reference distance \(d_{0}\). When using this parameter, Castalia provides the option of modifying the communication range [28]. The parameter PLd0 is calculated as follows:  
\[Tx\_power-\max(receiver\_seitivity,noise\_floor+5)-10\times path\_ loss\_exponent\times\log(range).\]  
In our case, we have used the default 50 meters value for the \(range\) variable. However, since we consider communication collisions and interferences, the communication range is much lower than the nominal.  
For the MAC layer, we have adopted the Carrier Sense Multiple Access with Collision Avoidance CSMA/CA protocol except for the case of RASeR, which imposes by default a Global TDMA MAC layer.
# 5G-MEC Testbeds for V2X Applications
## 5 Summary of Available Tools
### V2x  
V2X applications can benefit from the 5G-MEC testbeds and solutions to achieve URLLC. However, V2X application deployment and integration with the MEC system still need to be completed. The ETSI defines V2X application services and its MEC deployment scenarios. The V2X infrastructure is too complex to run real-time testbed experiments. However, some works have achieved V2I communication, and others have proposed simulation tools to test and run the experiments based on the V2X application needs.  
**Simulation of urban mobility** (SUMO) [103] is an open source tool used to create and experiment with simulated traffic scenarios. SUMO presents real-world graphs of road networks, where each vehicle has a unique identifier and includes information such as the departure time and route. SUMO [104] includes a time-discrete solution, where the default step length is 1 sec but it can be reduced to 1 ms. Traffic and communication factors are essential to obtain and run the V2X simulated scenarios, and SUMO needs to be coupled with ns3. ns3 is an open source simulator for external communication [105].
# Adaptive Noise Cancellation Based on Time Delay Estimation for Low Frequency Communication
## 2 Adaptive Noise Cancellation Based on Time Delay Estimation
### Time Delay Compensation  
When the reference inputs are used to reduce the noise, we need to know, not only the time-varying delays between primary input and reference inputs, but also which channel to be selected to collect the correlated noise. Because, if the reference noise is not correlated to the noise in the primary input, adaptive filter will not work and the SNR of output will decrease. Through time delay estimation, we can know the time-varying delay and relationship between primary input and reference inputs. For example, if the primary input and reference input 1 are correlated, the time delay estimation will converge to the steady state with a certain value and the noise in reference input 1 is chosen as reference noise. The proposed method works as shown in Figure 3.  
Figure 3: Adaptive noise cancellation based on time delay estimation.  
Figure 2: Explicit time delay estimation based on MCC (Maximum Correntropy Criterion).  
* Time Delay Estimation  
As shown in Figure 3, each reference input has an individual delay estimation module which estimates the time delay between primary input and reference input. The more correlated the noises are, the more accurate the estimated time delay is. If the SNR in the primary input is not very low, the communication signals cause a big error in time delay estimation. Therefore, the time delay estimation module may fail to converge in the communication process. In practical applications, the time delay should be corrected in the communication gap, based on the assumption that the noise source is the same during a communication process.
* Delay and Channel Control  
The delay and channel control module is used to set the time delay in primary input and chose the reference input. The time delay values obtained from the delay estimation modules of reference inputs are compared in this module. The reference input selected as the reference noise is the input with more accurate time delay value, having a smaller variance. Then the time delay is compensated to make sure that the delay between primary input and reference input is almost half the time delay of the adaptive filter.
* Noise Cancellation  
With time delay compensation, the adaptive filter can cover most significant part of the noise path's impulse response with a limited number of coefficients [25]. In addition, the ANC algorithm can be only applied to the active regions where the communication signals appear [24]. As a result, the complexity of ANC algorithm is reduced and the performance is greatly improved.
## 4 Discussion
### Influencing Factors
#### 4.4.4 Constant and Interval Loading  
Clear aligners are worn for extended periods each day, exposing materials to prolonged and repetitive mechanical forces. Several studies in this review demonstrated that both constant and interval loading significantly affect the mechanical behavior of thermoplastic aligner materials. Constant loading was consistently associated with substantial force decay or stress relaxation within the first hours of application, followed by a plateau [19; 20; 21; 26]. For instance, [PERSON] et al. [19] reported that forces applied by PET-G- and TPU-based samples reduced considerably during the first 8 h, after which the values stabilized. Similarly, [PERSON] et al. [20] found that all tested materials experienced rapid initial stress decay, but that TPU samples retained a higher percentage of residual force and exhibited lower stress loss than PET-G-based samples.  
Interval or cyclic loading, intended to simulate the daily insertion and removal of aligners, was explored in several studies [23; 31; 32]. [PERSON] et al. [31] showed that longer loading cycles resulted in greater stress relaxation, with specimens loaded for 23 h per day retaining only 5% of their initial residual force after one week. [PERSON] et al. [23] found that cyclic loading significantly reduced the magnitude of delivered force at clinically relevant deflections. Meanwhile, [PERSON] et al. [32] observed material-specific deterioration in elastic modulus and hardness, which became statistically significant only after 2500 thermal cycles, but not after 500, indicating a threshold effect in fatigue behavior.  
These findings highlight the viscoelastic nature of thermoplastic aligner materials and their susceptibility to mechanical degradation under functional wear conditions. While constant loading leads to an early drop in force delivery, cyclic use may contribute to the progressive loss of mechanical integrity. The diversity in testing protocols and materials, however, limits direct comparison. Future research would benefit from standardizing loading simulations and incorporating more realistic intraoral conditions to better reflect the performance of aligners during actual use.
## 3 MIMO Antenna Configuration Analysis
### Parallel Placement with Inverted Structure  
In this case, the MIMO antenna elements are parallel to each other, but the radiating patch is on the opposite side, as given in Figure 9. The suggested two-port MIMO antenna consists of an overall size of M\({}_{\text{X2}}\)\(\times\) M\({}_{\text{Y2}}\) = 20.5 mm \(\times\) 12 mm. The hardware prototype for this case is also fabricated to verify the predicated results. The space between two elements is fixed at G\({}_{\text{2}}\) = 4 mm to nullify mutual coupling between them.  
The transmission and reflection co-efficient of the suggested two-port MIMO antenna system is depicted in Figure 10a. It can be seen from the figure that the antenna exhibits an over wide band of 4 GHz ranging from 25.4-29.4 GHz with a return loss value of \(<\)\(-\)25 dB. The antenna offers S12 and S21 of \(<\)\(-\)38 dB at operational bandwidth. These results infer that the antenna elements have no net effect on each other. The software predicated results and hardware prototype results have no major differences which makes the suggested design a good applicant for MIMO application on 28 GHz.  
Figure 7: Comparison parameter of MIMO antenna with parallel element placement among (**a**) scattering parameters (**b**) axial ratio.  
Figure 8: Comparison among gain and numerically calculated radiation efficiency of MIMO antenna of parallel placement of element.  
Figure 10: Comparison of results of MIMO antenna with parallel placement and inverted structure of element (**a**) scattering parameters (**b**) axial ratio.  
Figure 9: Schematic of MIMO antenna for inverted parallel placement of elements.  
The AR of the suggested antenna is given in Figure 10b. It can be seen that the antenna offers a wide axial ratio bandwidth of 3 GHz for RHCP ranging from 26-29 GHz and 2.2 GHz for LHCP ranging from 26.3-28.5 GHz. Not much difference between software predicated results and prototype measured results is found, which makes the suggested antenna a a good candidate for future MIMO antenna devices in circular polarization application.  
The frequency versus gain plot, as well as radiation efficiency of the suggested two-port MIMO antenna, is given in Figure 11. The antenna gives a gain \(>\) 7.5 dBi at operational bandwidth with peak value of 8.6 dBi at 28.5 GHz. From the figure, it is also noted that the suggested concept provides a radiation efficiency of \(>\)97.75% at operational bandwidth with a maximum value of 98.2% at 28.5 GHz. The predicated and tested results show many similarities which makes the suggested antenna a good candidate for future high gain and high efficiency devices.
# A Novel Drone Design Based on a Reconfigurable Unmanned Aerial Vehicle for Wildfire Management
## 6 PULSAR Applications in Forest and Wildfire Management
### Payload Categorization and Integration  
The primary objective of this paper is the development of a singular, versatile UAV with the capacity to execute a wide array of missions in wildfires and prescribed sciences, thereby eliminating the necessity for multiple drones designed for specific tasks. To accomplish this objective, the UAV must be able to integrate all the required payloads according to the missions that the drone will execute. A list of all the required sensors that are needed and have been selected for each mission is available in Figure 14.  
Figure 14: Payload categorization for integration into the UAV.  
In this regard, the proposed strategy entails the creation of specialized casings for each payload, which can be effortlessly attached to the UAV. These casings will be fashioned using carbon materials, serving a dual role: safeguarding the payload sensors and streamlining the attachment process for end-users. This will be achieved by incorporating quick-pairing fasteners.  
The attachment process involves a simple plug-and-play procedure, wherein the users need only to position the casing in the dedicated space on the drone. Subsequently, they can secure the payloads along with their respective casings on the UAV by twisting the quick-pairing fasteners. This method ensures safety during flight, with the added benefit of an extremely short assembly and disassembly time, typically under a minute. It is worth noting that both the dedicated space on the UAV and the payload casings have been carefully designed to accommodate sensors of varying dimensions, underscoring the adaptability and versatility of the proposed drone.  
Below, considering all the points mentioned above, is a comprehensive overview of each payload, along with its uniquely designed case tailored exclusively to fit the drone, emphasizing the system's adaptability and flexibility.
# Internet of Things in Marine Environment Monitoring: A Review
## 2 Overview of IoT in Marine Environment Monitoring
### Typical Sensors and Sensing Parameters  
Sensors are used to respond to changes in their environments by producing electrical signals in the form of electrical voltage, current, or frequency [29]. There are typically two kinds of sensors: Physical sensors and chemical sensors. Physical sensors are used to measure different physical parameters like temperature, humidity, pressure, wind speed, and wind direction. Chemical sensors are used to measure various chemical parameters like salinity, turbidity, pH, nitrate, chlorophyll, and dissolved oxygen (DO). Details can be found in reference [18]. Decisions on the selection of sensors are made according to requirements related to the deployment area and season, measurement range, accuracy, resolution, and power consumption.
# Improving DFT-Based Image Watermarking Using Particle Swarm Optimization Algorithm
## 2 Background and Contributions
i.e., the pair of radiuses \(r_{1}\) and \(r_{2}\) in the magnitude \(M(u,v)\) used to build the annular area \(A\), and the watermark strength factor \(\alpha\), used by DFT-based invisible watermarking methods in an experimental manner. However, this manual adjustment may require exhaustive tasks and at the same time be a drawback in practical scenarios. In this way, modifying the same amount of DFT coefficients in a heterogeneous image database may be not the best choice, because, as is well known, the distribution of spectral information is not the same for all images in the dataset. For illustrative purposes, Figure 2a,b shows the DFT magnitude of the luminance of a couple of color images, the first one with predominant plain content and the second one with predominant texturized content. In this way, use of fixed values for the pair of radiuses \(r_{1}\) and \(r_{2}\) in the magnitude \(M(u,v)\) in a heterogeneous image database, will imply that the watermark strength factor \(\alpha\) should be adjusted experimentally in order not to affect the robustness, but invariably the watermark imperceptibility will be affected. According to the above, as shown in Figure 3, the aim of this proposal is to find the optimized values of the key parameters. i.e., the pair of radiuses \(r_{1}\) and \(r_{2}\) in the magnitude \(M(u,v)\) used to build the annular area \(A\), and the watermark strength factor \(\alpha\), proper for each image, instead to fix these values as is performed by the conventional DFT-based invisible watermarking methods, improving the performance in terms of robustness and imperceptibility using color images. In recent years, the scientific community has focusing its attention in optimize the performance and the key parameters of invisible watermarking methods via optimization algorithms, such as PSO algorithm [5]. In this context, a brief revision of state of the art related to invisible watermarking methods that employ the PSO algorithm with optimization purposes, is shown in Table 1.  
Figure 2: (a) Original image with predominant plain content and its DFT magnitude. (b) Original image with predominant texturized content and its DFT magnitude. Table 1 shows a current trend in the scientific community related to the use of PSO algorithm to improve the performance of invisible watermarking based on several frequency