esa-sceva/satcom-chunk-collection huggingface dataset:
## Appendix B Receiver Clock Modelling  
The oscillator frequency and phase are two states characterized into the random processes which are expected to make good sense in the receiver clock modeling. Supposing that two states \(x_{p}\) and \(x_{f}\) denote the clock phase error and clock frequency error, respectively, which are assumed to follow the distribution of the independent Gaussian white noise. Then, the associated variances and covariances within an elapsed time duration of \(\Delta t\) can be attained as  
\[\mathbf{E}\left[x_{p}^{2}\left(\Delta t\right)\right]=S_{f}\Delta t+\frac{S_{g }\Delta t^{3}}{3},\ \ \ \mathbf{E}\left[x_{f}^{2}\left(\Delta t\right)\right]=S_{g}\Delta t,\ \ \ \mathbf{E}\left[x_{p}\left(\Delta t\right)x_{f}\left(\Delta t\right)\right]= \frac{S_{g}\Delta t^{2}}{2} \tag{10}\]  
where \(\mathbf{E}\left[\cdot\right]\) represents the expectation operator; \(S_{f}\) and \(S_{g}\) stand for the noise spectral amplitudes of clock phase error and clock frequency error, respectively. Detailed descriptions related to the receiver clock modeling are given in the reference [66]. The clock drift characteristics can be depicted with Allan variance plots based on the previous studies. For example, a timing stability plot for a typical ovenized crystal receiver clock is illustrated in Figure 14.  
\(S_{f}\) and \(S_{g}\) can be estimated from two typical coefficients, i.e., \(h_{0}\) and \(h_{-2}\), and they are extracted from the Allan variance outputs of the objective clock drift as illustrated in Figure 14. The correspondence can be given by  
\[S_{f}=\frac{h_{0}}{2},\ \ \ S_{g}=2\pi^{2}h_{-2} \tag{11}\]  
More information about \(h_{0}\) and \(h_{-2}\) are stated in Section 2.1.1.
# Fuzzy Regulator for Two-Phase Gas-Liquid Pipe Flows Control
## 3 Two-Phase Flow Experimental Rig: Facility and Control Methodology  
The experimental rig was built at the Institute of Applied Computer Science at the Lodz University of Technology. The flow rig can be supplied with fluid from two storage tanks and by a multi-stage centrifugal pump. In one of the tanks, a propeller stirrer is installed to prepare for research on liquid-like aqueous solutions of the various substances. Due to the installed electromagnetic flow meters, it is possible to precisely set the volumetric flow rate. The maximum pumping stream of liquid (with a viscosity close to the viscosity of water) delivered by Grundfos pump CRN's 45 is 50 m\({}^{3}\)/h. In addition, the applied screw compressor DMD 100 CR allows obtaining the volume stream of air at 1000 L/min with a pressure of about 7 bar. A more detailed technical description of the rig, including the schemas and applied 3D electrical capacitance tomography (3D ECT) diagnosis principles, may be found in the authors' previous work [30]. Due to the characteristic features of the flow rig, it is possible to obtain all types of two-phase pipe flows commonly found in industrial applications.  
In Figure 1, the concept of the diagnostic control system for the experimental flow rig is depicted. The abbreviations used in the schema define the following signals: \(S_{G}\)--set value of gas stream; \(S_{L}\)--set value of liquid stream; \(f_{C}\)--current flow type; \(S_{PT}\)--process tomographic (i.e., 3D ECT) diagnostic signal; \(f_{T}\)--identified flow type; \(f_{G}\)--given flow type; \(N_{SG}\)--a new set of the gas stream; and \(N_{SL}\)--a new set of the liquid stream.  
The three parts: rig hardware (i.e., pump, flow meters, pipelines, etc.), diagnostic (i.e., 3D ECT and fuzzy identification module) and control are distinguished. Because the fuzzy regulator is designed to consider three input signals and provide two output signals, it can be classified as the so-called MIMO feedback control model [38]. The following section describes the regulator's input signals and their division into two classes.
## 4 Results and Discussion
### Technical Limitations  
Ambient noise methods offer indirect measurements and require calibration with ground truth data to enhance accuracy. The detection of low-frequency signals (<1 Hz) demands prolonged recording durations and expansive sensor arrays, whereas high-frequency noise (>20 Hz) is naturally attenuated by surface and subsurface conditions, limiting the resolution of deeper structures [69].  
Interpretation of ambient noise data depends on assumptions regarding wave propagation and subsurface heterogeneity, which can introduce errors, particularly in geologically complex settings where variations in subsurface materials and bedrock composition significantly influence results [70].  
Furthermore, HVSR inversion can face challenges in mode identification, leading to interference between Rayleigh and Love waves and potential inaccuracies in velocity estimations. In urban environments, increased high-frequency noise further reduces penetration depth, making deep structure characterization more difficult [71].
## 1 Introduction
[20] used hydrogel-assisted enzyme-induced carbonate precipitation (EICP), which showed that hydrogels retained water for a longer time, reduced the infiltration of solution in the soil, prolonged the reaction time, improved the efficiency of precipitation, and enhanced the formation of the crust. [PERSON] et al. [21] utilized a biopolymer-assisted EICP approach to improve soil water retention and reduce permeability by retaining carbonate around soil particles. Based on MICP technology, [PERSON] et al. [22] used polyvinyl alcohol (PVA) solution instead of water to prepare cementitious solution. The viscous polymer solution immobilized bacteria and cementitious medium on the surface, promoted calcium carbonate precipitation, formed uniform soil crust on the surface area, and reduced the corrosion ability of the soil. Hydroxypropyl methylcellulose (HPMC) is abundant, cheap, and biocompatible [23]. A gel can be formed by heating the solution. HPMC, because of its good water retention performance, is widely used in cement mortar as water retention agent and retarder, to improve the hardening strength, save the amount of cement, and then achieve the purpose of cost-saving. Because of its viscosity, HPMC is combined with MICP technology to react in the soil surface better, forming a hard crust on the surface and enhancing the surface strength. As mentioned above, MICP reinforcement of surficial soil is usually not ideal due to the high permeability of the soil; therefore, it has great potential for research on effectively stabilizing the surface layer of soil via MICP technology. In this study, a series of laboratory experiments were conducted to investigate the feasibility of using MICP and HPMC in the surficial treatment of soil for the purpose of improving the properties of the soil surface. The surficial treatment and ammonia adsorption were achieved by utilizing MICP and HPMC on the soil surface. The macro-scale characteristics of the treated specimens were studied, including the surface strength of sand, the content of CaCO\({}_{3}\), and the resistance to wind and rain erosion. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to further analyze the microstructure and formation mechanism under different treatments.
## 2 Experimental Setup
EDF, erbium-doped fiber; WDM, wavelength-division multiplexer; CIR, circulator; LD, laser diode; OC, optical coupler; SESA, semiconductor saturable absorber; C, collimator; PBS, polarizing beam splitter; H, half-wave plate; Q, quarter-wave plate; R-1, sub-ring 1 and R-2, sub-ring 2.  
the equivalent optical length of the fibers can be estimated as 6.1652 m. In the 0.2-m free space path, the equivalent optical length of three zero-order wave plates can be neglected. The polarization beam splitter of Thorlabs PBS104 is a 10-mm cube made of N-SF1, of which the refractive index is 1.6832 at 1550 nm [31, 32]. Considering the refractive index of air as 1.00027 [33], the equivalent optical length of the free space path can be estimated as 0.2069 m. With the total equivalent optical length of R-1 being 6.3721 m, the repetition rate of the comb generated from R-1 can be calculated as approximately 47 MHz. In comparison, the length of the SMF-28e+ fiber in R-2 is changed to approximately 3.48 m. The total equivalent optical length of R-2 is 6.0442 m. Accordingly, the repetition rate of R-2 should be varied to 49.6 MHz with the same calculation method above. It is clear that the slight difference between repetition rates of the combs from two sub-rings is introduced by the new dimension of the sub-ring structure. More importantly, this new dimension of the sub-ring structure enables a free variation of the difference between repetition rates. This is highly desired in many applications of multi-comb interferometry [2, 3, 9]. As the group velocity dispersion (GVD) of the EDF and SMF-28e+ are +0.012 ps\({}^{2}\)/m and \(-0.022\) ps\({}^{2}\)/m @ 1550 nm, respectively [18, 23], the net GVD of R-1 and R-2 can be estimated as \(-0.0732\) ps\({}^{2}\) and \(-0.0710\) ps\({}^{2}\), respectively, when neglecting the dispersion from the short space path. Therefore, both sub-rings in the current setup operate in the anomalous-dispersion regime. Optical couplers are applied to extract 10% power of the intracavity light as output. The multi-combs generated from the multidimensional multiplexing mode-locked laser were detected by photodetectors with 1.8 GHz bandwidth (Menlo Systems, APD310) and 150 MHz bandwidth (Thorlabs, PDA05 CF2). The latter was applied to monitor the repetition rates only. An oscilloscope with a 2.5 GHz sampling rate (Agilent Technologies, MSO9254A) and a spectrum analyzer with 3.6 GHz bandwidth (Agilent Technologies, N9010A) was applied to monitor the pulse train in the time domain and the radio frequency (RF) spectrum of the interference signal in the frequency domain, respectively. The optical spectrum and power of the generated combs were detected by an optical spectrum analyzer (YOKOGAWA, AQ6370C) and a dual-channel optical power meter (Thorlabs, PM320E).
## 3 Validation of Numerical Models
### Numerical Simulation of Electro-Impulse De-Icing on Wing Leading Edge Structure  
This study uses a model NACA 0012 wing with a chord length of 1000 mm. In Figure 12, the wing profile line is displayed. Only the de-icing of the wing's leading edge is studied because it is primarily covered with ice. The electric current distribution on the skin's surface near the coil is dense because of the skin effect of the electric current, and the skin force reduces as the electric current falls along the skin's thickness. Only the skin thickness is added at the coil's relevant point because adding the entire wing thickness would lead to further issues; this additional skin layer is also referred to as the doubler. In a subsequent study, the impulse force acted on the surface of the doubler. In both the span and chord directions, the ice size is close to what was seen in the experiment. The ice thickness in modeling is fixed at a constant value. The error was acceptable in the [PERSON] et al. [51] study comparing steady-thickness ice modeling with two other modeling techniques. By offsetting the wing profile lines, the ice and leading edge of the wing were modeled in three dimensions. The ice thickness is 4 mm, the skin thickness is 0.5 mm, and the span length of the leading-edge portion of the wing is 500 mm. Figure 13 illustrates the doubler's position at the wing's leading edge. A total of 60% of the chord length of the leading edge is where doubler one's center is situated, and 80% of the chord length is where doubler two's center is situated. A total of 24,892 C3D8R with an element size of 4 mm are used in the doubler's finite element modeling and the wing's leading edge. Globally embedded cohesive elements simulate the ice layer that adheres to the wing's leading edge; there are 19,402 cohesive elements, and 9800 solid elements, which have a dimension of 4 mm. Cohesive elements are again embedded between the ice layer and the wing contact surface to simulate the shedding of the ice layer on the wing surface after the ice layer and wing are combined. A total of 9800 cohesive elements are embedded between the ice layer and the wing contact surface. The uniform pressure on the surface of the doubler simulates the impulse force generated by the coil. Compared to the electromagnetic coupling analysis, this approach reduced analyzing time and demonstrated efficacy in the [PERSON] et al. [60] investigation. The wing skin was attached to the ribs and spar caps with appropriate boundary conditions determined by the experimental structure. Figure 14 displays the established finite element model of the wing icing.  
Figure 11: Debonding process of push-out: **(a)** start of debonding and **(b)** end of debonding.  
Figure 12: Wing profile line of NACA0012.
## 3 The Field Data  
The passive seismic data acquisition area is located in a mining area in Sichuan (as shown in the blue square in Figure 1a), where Triassic feldspar quartz sandstone, Jurassic marl-domite-feldspar quartz sandstone, Cretaceous purplish red mudstone-siltstone-sandstone, and Quaternary strata are exposed. Figure 1b shows a diagram of the geological structure of the mining area. The main structural direction of this area is north-northeast, followed by nearly east-west. Magmatic rocks in the mining area are mainly gabbro and diabase from the late Jinning period, which are exposed as rock masses and dikes of different sizes. The wall rock alteration is developed, among which the wall rock alteration related to mineralization mainly includes chloritization, silicification, and carbonization.  
We arranged a two-dimensional passive seismic survey line, P18-P18\({}^{\prime\prime}\), at the periphery of the mining area (as shown by the red dotted line in Figure 1b). The passive seismic data were continuously recorded for 4 days with a 1-millisecond sample interval using 120 node-type single-component geophone I-Nodal at 1-240 Hz natural frequency. The distance between each geophone was 12.5 m, and the total length of the survey line was 1.5 km. In order to avoid surface wind noise, the geophones were buried at depths of about 20 cm.  
The maximum elevation difference of the terrain in the test area was 100 m, and the slope was gentle. The surrounding areas were sparsely populated and underdeveloped, with one or two village-level roads. There were many rivers nearby, and there were mining activities about 4 km northwest. Comprehensive analysis showed that the noise in this area mainly came from rivers, traffic, and mining activities, and mining activities may be the main source of prominent noise events. Figure 2 shows the daily noise data recorded by a geophone.  
There was very little noise from night to morning (0-6 h), with relatively low amplitude and stable change, whereas during the day, due to activities such as surface mining, the noise amplitude was relatively high and changed drastically, including some prominent high-amplitude noise events (red arrows). Therefore, in order to satisfy the hypothesis of a theoretical wavefield as much as possible, the original field data were processed.
# An Experimental Evaluation of Path-Based Product Line Integration Testing and Test Coverage Metrics
## 5 Experimental Evaluation of the Method
### Research Questions  
Through these case studies, I aim to obtain answers to the following research questions:  
* _RQ1: Does path-based SPL integration testing allow us to avoid redundant testing?_ The answer to this RQ is \"yes\" if the path that has already been tested in the platform testing is not tested again in the product testing, when the testing is performed in accordance with the given xx-MM-path coverage. Otherwise, the answer is \"no\". This research question also confirms whether the proposed method can avoid redundant test coverage because avoiding redundant testing is closely related to avoiding redundant test coverage.
* _RQ2: Does path-based SPL integration testing reduce costs by avoiding redundant testing?_ To obtain the answer to this RQ I compare the cost of product line testing performed in a stand-alone fashion with the cost of testing a product line in accordance with the selected xx-MM-path test coverage. The cost of the path-based integration testing is calculated by summing the platform testing cost performed in accordance with the selected xx-MM-path test coverage and the total product testing cost of all member products that tests only those parts not covered by the platform testing. The answer to this RQ is \"yes\" if the cost reduction ratio is positive and \"no\" if the result is negative.  
The detailed variables and equations needed for cost/benefit analysis are given in Section 3.
* _RQ3: Do test cases derived from path-based SPL integration testing cover all method calls?_ The answer to this RQ is \"yes\" if test cases derived using MM-paths cover all possible method calls of the integrated system. Otherwise, the answer is \"no\". This result represents the possibility of detecting interfacing errors between modules.
# A Novel Wireless-Netted UWB Life-Detection Radar System for Quasi-Static Person Sensing
## 3 Design of Golay Complementary Coded Radar
### The Golay Complementary Coded Signal Transmitter
As shown in Figure 2a, the Golay complementary coded signal transmitter consists of a controller in FPGA, a 14-bit digital to analog converter (DAC) at a 2.5 GSPS update rate, two low-pass filters, a power divider and a low-noise amplifier with 21 dB gain. In order to adequately utilize the bandwidth of the antenna and emit more energy, the Golay complementary sequence is modulated by a sinusoidal signal. Meanwhile, to balance the penetration ability and the miniaturization of the antenna [27], the Golay complementary sequence with \(\sim\)1 ns impulse width and a center frequency of \(\sim\)1 GHz is adopted here. For the modulation of the Golay complementary coded signal, the value \"1\" in the sequence represents a single positive impulse, while the value \"0\" represents a single negative impulse. Instead of storing the transmitted waveform directly, both the single positive impulse and the single negative impulse are stored by bit. In this way, fewer ROMs of FPGA are required. A power divider divides the filtered Golay complementary coded signal into two identical signals: one is fed to the transmitting antenna for radiation, while the other is fed to the first channel of the receiver to obtain the reference signal for the pulse compression. The transmitted signal is shown in Figure 3a. In Figure 3b, the autocorrelation results of the Golay complementary coded signal A and signal B are presented, and the sidelobe of the sum of both is under \(-\)40 dB. Figure 3: (**a**) The Golay complementary coded signal sampled by the receiver. (**b**) The autocorrelation result of Golay code A, Golay code B and the sum of both.
# Antioxidant Capacity of Honey Enriched by Wildflowers
###### Abstract  
The study objective was a comparative analysis of rapeseed and multifolien honey enriched by flowers of six plant species: lungwort (_Pulmonaria officinalis_ L.), high mallow (_Malva sylvestris_ L.), cowslip primrose (_Primula veris_ L.), coltsfoot (_Tussilago farfara_ L.), lawn daisy (_Bellis preemuis_ L.), and black elderberry (_Sambucus nigra_ L.). The honey was enriched with dry flowers and plant extracts at a level of 1%, 2%, and 4% (\(w/w\)). Antioxidant capacity was measured via two different methods: DPPH and ABTS assay. Total phenolic content and total flavonoid content were determined using colorimetric methods. The highest radical scavenging capacity determined by the DPPH assay was observed in rapeseed honey with a 4% dried cowslip primrose (_Primula veris_ L.) flower addition, which was more than 50 times higher than the activity for pure rapeseed honey. Almost 100% of the radical scavenging capacity was found for rapeseed and multifolien honeys with cowslip primrose (_Primula veris_ L.), especially for the 4% dried flower addition, more than six times that of the control samples measured using the ABTS test. Multifolien honeys enriched with black elderberry (_Sambucus nigra_ L.) and cowslip primrose (_Primula veris_ L.), with a 2% and 4% plant material addition, both as an extract and as dried flowers, were characterised by the highest total phenolic content. The highest enrichment effectiveness was observed for dried flowers of lungwort (_Pulmonaria officinalis_ L.), black elderberry (_Sambucus nigra_ L.), and high mallow (_Malva sylvestris_ L.), where the flavonoid content increased more than nine times compared to the honey samples without additions. The content of biologically active substances in honey enriched with flowers gives hope for new applications of the health-promoting substances contained in wild plants.  
Keywords:wildflowers; rapeseed honey; multifolien honey; DPPH; ABTS; total phenolic content; total flavonoid content +
Footnote †: journal: Applied sciences
## Distance-Constraint _k_-Nearest Neighbor Searching in Mobile Sensor Networks  
**[PERSON], [PERSON], [PERSON], [PERSON] and [PERSON] ***  
Department of Computer Engineering, Kyung Hee University, Suwon 446-701, Korea;  
E-Mails: [EMAIL_ADDRESS] (Y.H.); [EMAIL_ADDRESS] (K.P.); [EMAIL_ADDRESS] (J.H.);  
[PERSON]RESS] (N.U.)  
* Author to whom correspondence should be addressed; E-Mail: [EMAIL_ADDRESS];  
Tel.: +82-31-201-3732; Fax: +82-31-202-3706.  
Academic Editor: [PERSON]  
_Received: 2 June 2015 / Accepted: 22 July 2015 / Published: 27 July 2015_  
**Abstract:** The _k_-Nearest Neighbors (_k_NN) query is an important spatial query in mobile sensor networks. In this work we extend _k_NN to include a distance constraint, calling it a _l_-distant _k_-nearest-neighbors (_l_-_k_NN) query, which finds the \(k\) sensor nodes nearest to a query point that are also at \(l\) or greater distance from each other. The query results indicate the objects nearest to the area of interest that are scattered from each other by at least distance \(l\). The _l_- _k_NN query can be used in most _k_NN applications for the case of well distributed query results. To process an _l_-_k_NN query, we must discover all sets of _k_NN sensor nodes and then find all pairs of sensor nodes in each set that are separated by at least a distance \(l\). Given the limited battery and computing power of sensor nodes, this _l_- _k_NN query processing is problematically expensive in terms of energy consumption. In this paper, we propose a greedy approach for _l_- _k_NN query processing in mobile sensor networks. The key idea of the proposed approach is to divide the search space into subspaces whose all sides are \(l\). By selecting \(k\) sensor nodes from the other subspaces near the query point, we guarantee accurate query results for _l_- _k_NN. In our experiments, we show that the proposed method exhibits superior performance compared with a post-processing based method using the _k_NN query in terms of energy efficiency, query latency, and accuracy.  
**Keywords:** wireless sensor networks; _k_-nearest-neighbors query; spatial queries