esa-sceva/satcom-chunk-collection huggingface dataset:
## 3 Modeling and Simulation
### Simulation Results
#### 3.3.2 Simulation Data with Different Initial Pressure of the Accumulator  
The initial pressure of the accumulator ranged from 19 MPa to 22 MPa at the interval of 1 MPa when the braking intensity was kept at 0.4 and the initial braking speed was set at 300 rpm. In this section, the obtained evolutions of speed of the flywheel and pressure of the accumulator were shown in Figure 6a,b, respectively, and the braking time, change of the kinetic energy, recycled energy amount, and the energy recovery rate with different initial pressure of the accumulator were calculated and summarized in Table 4. It could be observed, that effect of the initial pressure of the accumulator to the energy recovery rate was unobvious, and the energy recovery rate was slightly decreased along with increase of initial pressure of the accumulator. The reason for this phenomenon was that difficulty degree of the energy recovery was gradually increased along with increase of the initial pressure due to the performance characteristics of the accumulator, and stability of absorption and desorption of the accumulator indicated that change of the initial pressure would not affect the energy recovery rate significantly.  
Figure 6: Simulation results with different initial pressure of the accumulator: (**a**) Evolution of speed of the flywheel, (**b**) Evolution of pressure of the accumulator.  
\begin{table}
\begin{tabular}{c l c c c c} \hline \hline Parameters & \begin{tabular}{c} Braking intensity \\ Initial pressure of the accumulator (MPa) \\ Initial braking speed (rpm) \\ \end{tabular} & 0.30 & 0.35 & 0.40 & 0.45 & 0.50 \\ \hline \multirow{3}{*}{Results} & \
\begin{tabular}{c} Braking time (s) \\ Kinetic energy change (J) \\ The recycled energy by the accumulator (J) \\ Energy recovery rate (\%) \\ \end{tabular} & 19 & 19 & 19 & 19 & 19 \\ \cline{1-1}  &
\begin{tabular}{c} Braking time (s) \\ Kinetic energy change (J) \\ The recycled energy by the accumulator (J) \\ Energy recovery rate (\%) \\ \end{tabular} & 300 & 300 & 300 & 300 \\ \hline \hline \end{tabular}
\end{table}
Table 3: The simulation results in the operating mode with different braking intensity.
## 1 Introduction
Whenever this number becomes statistically greater than those of the neighbors that are interfering femtocells, the FBS is then instructed directly from the MBS to adjust its transmitted power. Conversely, the FBSs work independently to decrease their transmitted power by using the RSSs report sent by the closest MUEs. In the first case, the FBS is instructed centrally by the MBS; however, in the second case, the FBS works autonomously and in a distributed way for adjusting their transmission power. Upon mitigating interference and in order to test our solution, we initiate video streaming applications through the MUEs and FUEs in order to investigate the effect of our power adjustment on the QoS of this application. This article is organized as follows: starting with the main assumptions of the system model in Section 3, the proposed power adjustment scheme is presented in Section 4. This is followed by introducing the adaptive method of rate matching in Section 5 and the simulation environment is defined and results are presented in Section 6. Conclusions are presented in Section 7.
# Adaptive Fuzzy-Based Fault-Tolerant Control of a Continuum Robotic System for Maximly Sinus Surgery
###### Abstract  
Continuum robots represent a class of highly sensitive, multiple-degrees-of-freedom robots that are biologically inspired. Because of their flexibility and accuracy, these robots can be used in maxillary sinus surgery. The design of an effective procedure with high accuracy, reliability, robust fault diagnosis, and fault-tolerant control for a surgical robot for the sinus is necessary to maintain the high performance and safety necessary for surgery on the maxillary sinus. Thus, a robust adaptive hybrid observation method using an adaptive, fuzzy auto regressive with exogenous input (ARX) Laguerre Takagi-Sugeno (T-S) fuzzy robust feedback linearization observer for a surgical robot is presented. To address the issues of system modeling, the fuzzy ARX-Laguerre technique is represented. In addition, a T-S fuzzy robust feedback linearization observer is applied to a fuzzy ARX-Laguerre to improve the accuracy of fault estimation, reliability, and robustness for the surgical robot in the presence of uncertainties. For fault-tolerant control in the presence of uncertainties and unknown conditions, an adaptive fuzzy observation-based feedback linearization technique is presented. The effectiveness of the proposed algorithm is tested with simulations. Experimental results show that the proposed method reduces the average position error from 35 mm to 2.45 mm in the presence of faults.  
continuum robot manipulator; maxillary sinus surgery; T-S fuzzy algorithm; variable structure algorithm; observation technique; fuzzy ARX-Laguerre system modeling; feedback linearization observer; adaptive technique; fault diagnosis; fault-tolerant control
## 7 Implementation and Evaluation
### Adaptation Services  
Each of our services has a well-defined Web service interface which we use for protocol issues (cf. Section 6). Through this interface we can start, stop and monitor the service.  
As a first step we developed services to provide multimedia adaptation functionality, since there are no such services on the market. We exploited several concepts to enable service-oriented media streaming. While searching for a suitable solution, we faced the big problem that the multimedia market is a closed source one. Especially Java lacks multimedia support. There is just one official standard API on the market: the JavaMedia Framework (JMF), which was introduced in 1998. However, the development of the JMF has been discontinued in 2004. There are some projects relying on JMF, e.g., FFMPEG-Java (FMJ) and Jffmpeg, but for us none of them offers satisfactory multimedia support. To solve this problem we implemented a Java wrapper for the command line tools mencoder and ffmpeg. Both rely on the libavcodec codec collection and, therefore, support a lot of codecs and multimedia capabilities. We encapsulated this wrapper by implementing the PUMA protocol bundle introduced in Section 6. Therefore, as is usual in service-oriented architectures, we are not bound to a certain programming language and are able to deliver multimedia content via different service implementations. For example, we integrated C#.NET Web services in our delivery workflow that perfectly interact with its adjacent Java services via the PUMA protocol.
# A Novel Mosaic Method for Spaceborne ScanSAR Images Based on Homography Matrix Compensation
## 3 Traditional Feature-Based Mosaic Process for SAR Images
### Overlapping Area Coarse Extraction  
As mentioned in the introduction, the keypoints that could be matched correctly were from overlapping areas between adjacent images. In that case, a large number of redundant keypoints were acquired from nonoverlapping areas, which would cause considerable computational redundancy in keypoint matching. The accuracy of matching and the efficiency of mosaics would both be affected. To solve this problem, we reduced the range of keypoint detection from the whole images to the overlapping areas. First, we calculate the actual longitude and latitude of the pixels using the geolocation technologies of spaceborne SAR [40; 41; 42]. The mature geolocation technologies used in this paper were efficient enough and took time in seconds. Then, the overlapping rates were estimated by the longitude and latitude of the pixels. Finally, the overlapping areas of adjacent images were coarsely extracted based on the overlapping rates. Only the keypoints in overlapping areas would be detected and matched, while nonoverlapping areas that accounted for a large proportion would not be involved in the registration.  
We used \(r_{\alpha}\) and \(r_{\beta}\) to represent the overlapping rates of \(I_{\alpha}\) and \(I_{\beta}\):  
\[r_{\alpha}=\frac{\text{card}\big{(}L_{\alpha}\cap L_{\beta}\big{)}}{\text{card }(L_{\alpha})} \tag{6}\]  
\[r_{\beta}=\frac{\text{card}\big{(}L_{\alpha}\cap L_{\beta}\big{)}}{\text{card }\big{(}L_{\beta}\big{)}} \tag{7}\]  
where \(\text{card}(\cdot)\) represents the number of elements in the set, \(L_{\alpha}\) is the longitude and latitude of all the pixels in \(I_{\alpha}\), and \(L_{\beta}\) is the longitude and latitude of all the pixels in \(I_{\beta}\). As shown in Figure 4, the overlapping areas were extracted from the whole images based on the overlapping rates.  
Figure 3: The intensity distribution trends along the stitching seam of two images before and after classic Wallis filtering. (**a**) The situation of similar trends; (**b**) the situation of opposite trends.
## 3 System Description
### Keystroke Recognition  
The underlying principle behind keystroke and gesture recognition is that a typing finger incurs changes in the transmitted signal. This is dependent on both the location and the movement of the finger, as depicted below.  
In Figure 2, we illustrate a side view of the keystroke recognition system model, in which a hand can be seen moving as it presses a key. In this model, there are 2 contributing factors to the multipath propagation environment.  
1. Firstly, the static channel multipath profile will be defined by the position of the hand in 3D space, as demonstrated by the \(x,y,z\) plane in Figure 2. When typing on a keyboard, the signals between the Tx and Rx encounter distinct reflection and attenuation patterns due to the hand's position over the keys in 3D space.
2. In the diagram shown in Figure 2, when the hand presses a key, the signal paths reflected by the object are dynamically altered. This leads to a ripple effect in the CSI  
Figure 1: Adopted WiFi sensing system architecture.  
time series data, with each key press causing changes in the multipath environment between the initial profile (dashed line), the pressed profile (solid line), and back to the initial profile.  
In this paper, we iteratively validate the viability of a keystroke recognition model. We begin by demonstrating the effectiveness of the static CSI profile for predicting hand positioning, followed by the use of dynamic CSI profiles for classifying the keystrokes.
# Research on Safe Following Distance on an Expressway Based on Braking Process Analysis
## Modeling  
### Analysis and Assessment of Braking Distance  
#### 3.1.1 Running Status of Automobiles  
Let car A (the front car) and car B (the following car), which are arranged longitudinally and separated by distance \"\(D\)\" (unit: m), drive successively in the same direction on the same road. This is shown in Figure 1. The two cars drive at the speeds of \(V_{A}\) and \(V_{B}\), respectively.  
It is assumed that the driver of car A starts to brake after finding obstacles in the front of the road. When the speed of car A decreases to \(V^{\prime}{}_{A}\), the distance driven by car A is \(D_{A}\). At the same time, the driver of car B starts to brake after observing car A's braking, and the distance traveled by car B when its speed decreases to \(V^{\prime}{}_{B}\) is \(D_{B}\). The symbol \(d\) (m) is the actual distance between car A and car B when car A and car B reach the post-braking speed, \(V^{\prime}{}_{A}\) and \(V^{\prime}{}_{B}\), respectively, as required by design.
# A Heuristic Approach for a Real-World Electric Vehicle Routing Problem
## 4 Solution Approach
### Removal Heuristics
#### 4.3.3 Worst Removal Heuristic  
The worst removal heuristic attempts to remove customers with high cost and insert them at another position in the solution to obtain a better solution. Given customer \(i\) served by some vehicle in solution \(s\), \(cost(i,s)=f_{\text{gen}}(s)-f_{\text{gen}}{}^{-i}(s)\) where \(f_{\text{gen}}{}^{-i}(s)\) is the cost of the partial solution without customer \(i\). At each iteration, an array \(L\) containing all visited customers from solution \(s\) not in \(D\) is constructed. This array is sorted according to descending _costs_. Then, a random number \(y\) is chosen from the interval [0, 1) and customer \(L[y^{p\text{worst}}\mid L\mid\)] is removed and put into \(D\). This process is repeated until \(q\) customers are removed from solution \(s\).
## 5 Rhodium
### Rhodium-Catalyzed Carbonylation, Hydroformylation and Hydrogenation  
[PERSON] and co-workers used a polymer-supported rhodium complex for the carbonylation of methanol to prepare acetic acid [32]. The solid support was prepared from 2-vinylpyridine and ethylene glycol acrylate via crosslinking copolymerization, and subsequently treated with [Rh\({}_{2}\)(CO)\({}_{4}\)]Cl\({}_{2}\) followed by tetraphenylboron to form the chelating complex **15** (Scheme 12). Acetic acid could then be formed from methanol under a carbon monoxide pressure of 3.2 MPa at 135 \({}^{\circ}\)C.  
**Scheme 12.** Carbonylation of methanol to form acetic acid and other products.  
[PERSON] _et al._ have prepared a catalyst from Rh(acac)(CO)\({}_{2}\) and polymer supported triphenylphosphine, and applied it in the hydroformylation of 1-hexene with syngas (Scheme 13) [33]. The reaction was carried out both in supercritical carbon dioxide and in organic solvents such as toluene and ethyl acetate, where scCO\({}_{2}\) was found to be superior in terms of reactivity and selectivity of the hydroformylation. The CO\({}_{2}\)-pressure was also found to affect the reaction, with a higher pressure affording more 2-hexene at the expense of the branched hydroformylation product. [PERSON] and [PERSON] have also applied a polymer-supported rhodium catalyst in hydroformylation [34]. The support used was an amphiphilic resin, prepared via ring opening metathesis polymerization, with a pendant dipyridyl-2-ylamide moiety functioning as the ligand to rhodium. Hydroformylation of 1 octene was performed under micellar conditions with good results, the supported catalysts affording a higher selectivity for the linear product than the homogeneous analogue.  
**Scheme 13.** Hydroformylation using a polymer-bound rhodium catalyst.  
Reduction reactions are not treated to any great extent in this review, but one example of a successful asymmetric hydrogenation reaction will be included here. [PERSON] and co-workers have evaluated polystyrene-supported bidentate aminophosphate-phosphate and -phosphine ligands in the asymmetric hydrogenation of conjugated methyl esters [35]. A library of resin-bound ligands was prepared in borane protected form and deprotected with diethylamine prior to treatment with a solution of [Rh(cod)\({}_{2}\)]BF\({}_{4}\) to form the hydrogenation catalyst. Three different methyl esters were used as substrates in the screening of the ligands and the outcome both in terms of yield and stereoselectivity varied strongly depending on the structure of the ligand. One of the more successful examples, using polymer-bound ligand **16**, is shown in Scheme 14.  
**Scheme 14.** Polymer-supported chiral bidentate phosphorus ligands in the asymmetric hydrogenation of methyl \(\alpha\)-acetamidoacrylate.
## 4 Discussion  
### Microstructure-Mechanical Properties Correlation  
The results have shown that the microstructure and therefore mechanical properties can be tailor made. The STA heat-treated specimens show a high mechanical strength and low elongation at break. This is due to the small size and the needle shape of the \(\alpha_{\mathrm{s}}\) precipitations formed during the short quenching and aging periods. At the solution step \(\alpha_{\mathrm{p}}\) is dissolved. However, precipitates can grow during further heat treatment. Furthermore, it can be assumed that the temperature is not sufficient to completely dissolve the as-built microstructure during the solution step. Hence, a fraction of the original \(\alpha_{\mathrm{s}}\) remains as part of the microstructure. \(\alpha_{\mathrm{s}}\) precipitations can grow during the aging step, but due to the short dwell time (60 min) and relatively low temperatures (500 \({}^{\circ}\)C) the needles remain small and their needle shape is preserved. These create, along with the \(\beta\)-matrix dislocation barriers, the very high mechanical strength and the low elongation at break. The achieved mechanical properties are comparable to conventionally produced and heat-treated Ti-5553 parts [11]. Other research groups show that by increasing the aging temperatures as well as the respective holding time the elongation at break can be enhanced, while the mechanical strength is decreased [15]. Compared to the STA heat treatment, the specimens heat-treated using the BASCA heat treatment show very good ductile properties and balanced mechanical strength--see Table 2. Due to the high annealing temperature (890 \({}^{\circ}\)C) and long holding times (90 min), it can be assumed that the as-built microstructure is completely dissolved. The more coarse primary and secondary \(\alpha\) precipitations lead to very ductile properties due to the good deformability of the \(\beta\)-matrix and the slip, shear and twinning mechanisms of the precipitations. As shown in Table 2, the achieved elongations at break for the in situ tensile-tested specimens are very low.
## 4 Performance Evaluation Results and Discussion  
### Experimental Setup and Method for Performance Evaluation  
Experiments were carried out to verify the performance of the proposed information recommendation methods using social network data. The experiments were based on Yelp data. The category of the information recommendation is restaurants. The number of users considered were 55,452, the number of restaurants were 5556, and the total number of reviews considered were 233,718. The components of the user influence and user activity were mapped to Yelp data attributes, as described in the Sections 3.1 and 3.2. The reviews could obtain 11 types of different feedback responses from users and 7 of the types were considered as positive feedback responses.  
The user influence and user activity were calculated for all 55,452 users. The users were then sorted in the order of high to low user influence and user activity, respectively. We suggest that the users showing high user influence or high user activity can provide a rating that would be acceptable to most users. This means that the rating provided by the user with high user influence or high activity should mostly be in line with the overall ratings of all users that provided ratings for the restaurant. To verify this, we first chose the top 10 users with the highest user influence and the highest user activity, respectively. The most recently visited 10 restaurants by each user were selected. For each of these restaurants, we then compare the rating provided by the user in the top 10 with the average rating of all users. This will show how much the user with high influence or high activity can represent the users. If this difference is small, it means that the user with high influence or high activity provides a representative rating. Otherwise, if the difference is large, it means that the rating provided is not a very representative one.  
In most information recommendation approaches that use social network data, the friend information is used. We compared our proposed approach against the approach where only the friend information is used. We first identify the top 10 users that have the largest number of friends. The ratings of the 10 most recently visited restaurants by each of these users are compared against the overall ratings by all users that have given a rating. If the difference is small, the user with many friends provides a representative rating. Otherwise, the rating provided is not a very representative one.  
Some additional analyses were performed to investigate the relationship between the user influence or user activity and some interesting attribute variables in Yelp. The Pearson correlation method was used to calculate the correlation.
# Adaptive Rate-Compatible Non-Binary LDPC Coding Scheme for the B5G Mobile System
## 4 Design and Performance Simulation of the Adaptive RC-NB-LDPC Coding Scheme  
This section presents the simulation results, which are described in three parts. The first part presents the performance comparison of the constructed RC-NB-LDPC codes with the DVB-S2 short codes. The second part presents the clustering results by the k-mean++ algorithm. The third part presents the advantages of the adaptive coding scheme in compressed image processing.
## 3 System Model
### TWDM-PON Enabled C-RAN Architecture  
Dedicated point-to-point fibers is a solution candidate for fronthaul transport network. However, considering of the greenhouse effects and energy shortage, it is not attractive due to the high cost and energy consumption. The energy consumption mainly caused by the large-scale deployment of fibers and transceivers. PON is gaining more attention because of its great potential [46; 47; 48]. Different PON techniques have been widely explored for fronthaul, such as wavelength division multiplexing (WDM) PON [46; 47], and subcarrier multiplexing (SCM) PON [48]. Meanwhile, TWDM-PON is regarded as a potential solution candidate for the fronthaul, because of its high capacity and low energy consumption [49]. Figure 1 depicts the energy efficient reconfigurable TWDM-PONenabled C-RAN architecture for smart home network. In C-RAN, ubiquitous RRUs perform the radio signals forwarding and digitizing from all mobile devices in each small cell. We assume that only one corresponding ONU is connected with each RRU serving the smart home gateway. Multiple CPRI links are de-multiplexed/multiplexed at the optical line terminal (OLT). In the BBU pool, baseband digital signals are processed by the virtualized BBU, based on the real-time flexible scheduling and high-performance processors.  
For the reconfigurable fronthaul network, TWDM-PON is a promising candidate solution, whose benefits has been widely explored [49]. The traffic from multiple ONUs can be multiplexed in the same wavelength resource, thanks to the time and wavelength multiplexing technique. Different independent virtual PONs (VPONs) will be formed when different wavelengths are used for data transmission [20], leading to a reconfigurable virtual fronthaul network. In addition, it is known that the tidal effect is obvious during the day in both office and residential cells. However, in traditional C-RAN, the CPRI bitrate is constant regardless of traffic variation, while dependent of the number of used antennas. For instance, for one \(2\times 2\) multiple input multiple output (MIMO) and 20 MHz bandwidth LTE sector, the required CPRI link rate is 2.4576 Gbit/s, leading to a low transmission efficiency since only 150 Mbit/s is useful for the mobile devices in a small cell on the air interface [50]. To accommodate the high demand traffic, different fronthaul compression techniques have been widely studied [37; 51]. Meanwhile, compression technique based bitrate-variable CPRI was introduced [42]. This paper considers compressed bitrate-variable CPRI as a key factor for the challenge in smart home. Furthermore, based on the operation mode of each small cell, part of the fronthaul links and other active units such as ONUs and transceivers can be shut down without energy supply at proper times [52; 53; 54]. Moreover, both virtual topology of reconfigurable fronthaul and operation modes of small cells can be abstracted in the controller based on the software defined network technique. Energy and transmission efficiency enhancement approaches can also be easily implemented and updated with the traffic variation during the days.