esa-sceva/satcom-chunk-collection huggingface dataset:
# A Review on the Recovery and Separation of Gallium and Indium from Waste
## 3 Methods of Recovering Gallium and Indium from Secondary Sources
### Solvent Extraction
#### 3.3.1 Extraction of Ga  
Gallium extraction from mixtures containing concentrated acids is very efficient when a mixture of trialkylphosphine oxides, known under the trade name Cyanex 923, is used as the extractant, to which bis-(2,4,4-trimethylpentyl)octylphosphine oxide (with the trade name Cyanex 925) is added [61].  
At higher pH values (approximately 2-4), gallium extraction is almost quantitative when carried out using the following substances: 2-ethylhexylphosphonic acid 2-ethylhexyl alcohol ester (EHEHPA), PC 88A), di-(2-ethylhexyl) acid phosphoric acid (D2 EHPA), di-(2,_A4_'-trimethylpentyl)phosphinic acid (DTMPPA), and derivatives of 2-methyl-8-quinolinol and a mixture of 5-dodecyl salicylic aldehyde oxime and 2-hydroxy-5-nonylacetophenone oxime (LIX 973N) [62; 63; 64].  
If the pH of the solution is more alkaline, high process efficiency is ensured using primary amines or a mixture known under the trade name Cyanex 921 as extractants, the main active ingredient of which is trioctylphosphine oxide [31].  
Gallium very often occurs in the company of Al(III), Cu(II), and Zn(II). In the solutions, Ni(II) and Fe(III) ions, as well as In(III), very often can be found [65]. However, the separation of gallium and indium will be discussed later in the chapter.  
Since the need to take into account the influence of so many factors generates a large number of \"combinations\" in the solutions after leaching, an example will be presented of the selective extraction of gallium from solutions of hydrochloric acid of various concentrations and with different accompanying metals.  
If, in a solution in which the HCl concentration is 5 M, gallium(III) is present in the company of zinc(II) and copper(II), Cyanex 923 and Cyanex 925 will work great as the selective extractants. Their biggest advantage is the fact that small amounts of zinc and copper, which will also pass with gallium into the extractant, can be easily washed out with distilled water. Gallium is removed from the extractant during a solvent regeneration step using an HCl solution [31]. CIGS wastes are materials considered as a viable source for the recovery of Cu, In, Ga, and Se. Using 4 M hydrochloric acid, Cu, In, and Ga can be leached with efficiencies around 99.98%, 93.40%, and 96.86%, respectively. Then, In and Ga can be sequentially extracted using P204, while Cu remains in the solution. Through solvent extraction, the extraction efficiency for In can reach 99.92%, and that of Ga can exceed 99.34% [34].
# Using Virtual Soundwalk Approach for Assessing Sound Art Soundscape Interventions in Public Spaces
## Materials and Methods
### Selected Urban Open Spaces
#### 2.1.2 Kunsthaus Graz, Lendkai, Graz (Location B)  
The electroacoustic sound art installation with musical features--Time Piece Graz is located at the Kunsthaus Graz contemporary art museum site. The electro acoustic system is placed on the roof of the museum, intended to be heard in the adjacent plaza and street, and the neighboring riverbank [64]. Permanent electro acoustic art installation was conceived with the aim of playing a synthesized sound for 5 min every hour regardless of the changing external factors. It is a sound art piece by [PERSON]--Time Piece Graz designed for a large public space [65]. The track contains a continuous crescendo of one tone cluster roughly between 92 Hz and 352 Hz, as observed in the spectrogram  
Figure 2: Spectrograms of 5 s-long excerpts, recorded as described in Section 2.2.1, with visible sound sources from soundscape interventions from the Locations (**A**), (**B**), and (**C**) (from left to right). Spectrograms were created using the application RX 6 Audio Editor v6.00.1210 (by iZotope).  
shown in Figure 2. In 2004, it was reprogrammed so its schedule fits the requirements of the law on noise mitigation (the installation is silent between 21:50 and 8:50) [64].  
The museum was built from 1999 until 2003 for the Kulturstadteuropas campaign in 2003 as a part of the revitalization of the historical city center. The design was chosen at a public design competition. The sound art installation is a product of the cooperation between architectural studio Fournier & Cook and sound artist [PERSON].  
South end of the Lendkai street and promenade at the joint with bridge Hauptbrucke is visually and aurally emphasized by the unusual corner building of the museum of modern art Kunsthaus Graz. The electroacoustic system placed on the rooftop of the prominent part of the volume of the museum (the so-called Needle; the unusual architectural composition consists of three components: the iron house--existing building originally constructed in 1848, the bubble--distinctive rounded glass structure, the needle--elongated volume 'hovering' over the plaza and the street) contains the sound source directed at the immediate urban area [66].  
The museum building is located on the crossroad, with one of the streets featuring tram lines and the other (one-way) car lanes. The second road, Lendkai features a river side promenade and densely planted high trees. Next to the promenade, down below is the river Mur, classified as a mountainous river [67], usually generating loud water sound.
# A Comparison of the Effects of Binaural Beats of Audible and Inaudible Frequencies on Brainwaves
###### Abstract  
The purpose of this study was to observe the effects of audible and inaudible binaural beat stimuli on alpha power elicitation and compare the differences in triggering effects depending on sound perception. Experiments were conducted on healthy male and female subjects (11 males and 10 females, mean age of 24.6 \(\pm\) 1.8). To induce alpha waves, audible (250 Hz) or non-audible baseline sound frequencies (18,000 Hz) were presented to the left ear, and a frequency 10 Hz higher than the baseline was presented to the right ear. There were two experimental phases: a rest phase (5 min) in which no stimulus was presented and a stimulation phase (5 min) in which the binaural beat stimulus was presented. An electroencephalogram was measured at a sampling rate of 500 Hz, and relative alpha power values were calculated for each phase in each brain area. In the central regions, both baseline frequencies (audible and inaudible) increased the relative alpha power during the stimulation phase compared with the rest phase, and there were no differences between the two baseline frequencies. In the frontal and central regions, there was a greater increase in relative alpha power in the audible case compared with the inaudible case.  
binaural beat; audible; inaudible; electroencephalogram +
Footnote †: journal:  
used the sound of music as a baseline frequency on top of which the BB stimulus was overlaid [11; 14]. The brainwave induced by the audible BB stimulus and the cognitive and emotional effects may be affected by both the sound perception (baseline frequency) and the frequency difference. Thus, BB can be effectively applied only when a few studies that evaluate the effects of such sound perception can validate scientifically the effectiveness of BB. There are reports indicating that auditory stimulation in the inaudible frequency range could affect human recognition and psychology. This phenomenon is called the hypersonic effect. Moreover, auditory stimulation, including that in the inaudible frequency ranges, can increase the alpha-wave and comfortable listening levels [15].  
This study verifies the effects of inaudible binaural beat (BB) by comparing it with audible BB. When analyzing the effect of audible BB, the effect of auditory perception at the baseline frequency cannot be excluded. Therefore, the study aimed to investigate whether inaudible BB has similar effects as audible BB by comparing the two. Thus, this study examined the effects of inducing brainwaves with BB and an inaudible baseline frequency. It was determined that a specific brainwave (\(\alpha\)) was induced when a BB with a baseline frequency of 18,000 Hz and a frequency difference of 10 Hz was presented. Furthermore, the effect of BB based on the commonly used audible baseline frequency (250 Hz) on inducing the brainwave (\(\alpha\)) was also observed to compare the effects of audible and inaudible baseline frequencies.
# A Novel Consistent Quality Driven for JEM Based Distributed Video Coding
## 3 Proposed JEM Based DVC (JEM-DVC)  
### Proposed JEM-DVC Architecture  
Figure 2 shows the architecture of our proposed JEM-DVC codec, where the highlighted blocks present the new coding methods that are proposed in this paper. As shown in Figure 2, the proposed JEM-DVC architecture also follows the Stanford DVC approach, specifically the DISCOVER DVC codec, which is described in the previous section. However, in the proposed architecture, instead of using the conventional H.264/AVC Intra coding, the proposed JEM-DVC codec employs several advanced coding techniques provided by the JEM/FVC [17]. Though the codec itself is not the core novelty of this paper, our proposed JEM-DVC codec is the first DVC codec in literature that employs JEM Intra coding, and thus all of the results presented in this paper are new. In the next subsections, we describe the proposed JEM based key frame coding and the consistent video quality control for the proposed JEM-DVC codec in detail.
## 3 State of the Art
### LTE and Wi-Fi in a Nutshell
#### 3.1.2 Wi-Fi  
Wi-Fi uses the Distributed Coordination Function (DCF) as the fundamental mechanism to access the medium and is designed to be asynchronous and decentralized [9]. Additionally, it uses the OFDM digital modulation scheme that divides the spectrum into multiple OFDM subcarriers spanning 20 MHz or multiple spectral portions of 20 MHz. In order to sense and gain access to the medium, Wi-Fi uses the Carrier Sensing Multiple Access with Collision Avoidance (CSMA/CA) mechanism before a packet transmission. According to this contention-based protocol, a Wi-Fi node first has to listen to the shared medium to determine if there are other ongoing transmissions. This procedure is known as Clear Channel Assessment (CCA). The node senses the channel for a DCF Inter-Frame Space (DIFS) duration. Only when the channel is estimated as idle is the node permitted to transmit.  
CCA consists of two functions named Carrier Sense (CS) and Energy Detection (ED). The CS function refers to the ability of the receiver to detect and decode a received Wi-Fi preamble. According to the specifications, if the power of the detected signal is higher or equal to \(-82\) dBm for the 20-MHz bandwidth, then CCA reports the channel as busy for the timeslot that is indicated in the frame's  
Figure 3: LTE time-frequency structure and user traffic scheduling. Each color represents a different UE that is scheduled by the Base Station.  
Physical Layer Convergence Protocol (PLCP) length field [9]. This field contains either the time in \(\upmu\)s that is required for the Medium Access Control (MAC) Protocol Data Unit (MPDU) payload transmission or the number of octets carried in the frame MPDU payload, which is used to compute the time required for the MPDU transmission.  
If the received signal cannot be decoded, the ED function is used. The ED function refers to the ability of the receiver to detect the energy level in the operating channel based on non-Wi-Fi signals that are sensed, introducing interference, or based on corrupted Wi-Fi transmissions that cannot be decoded. If the energy level is higher than \(-62\) dBm for a 20-MHz bandwidth, then CCA reports the channel as busy. ED senses the channel every time slot to estimate the corresponding energy level [9].  
In case the channel is sensed as idle for a DCF Inter-Frame Spacing (DIFS) period, then the Wi-Fi node can transmit. Otherwise and also prior to attempting to transmit again immediately after a successful transmission, the node has to postpone its transmission and wait for a free DIFS plus a random backoff time to avoid packet collisions. After a transmission, the node waits for an acknowledgment during a Short Inter-Frame Space (SIFS) period. If the acknowledgment is not received after this timeout period, the node schedules a retransmission after a new exponential backoff period and until the maximum number of retransmissions is reached. Figure 4 illustrates the CSMA/CA algorithm described above.
## 4 Applying ADMM to the Ordered Ridge Regression
### Over-Relaxed ADMM Algorithm  
By comparing Equations (1) and (6), we can write Equation (6) in the over-relaxation form as follows:  
\[\alpha x^{k+1}+(1-\alpha)z^{k}\xrightarrow[\alpha^{real}-\gamma^{th}]{x^{k+1} +(1-\alpha)z^{k}+\alpha^{real}} \tag{13}\]  
Substituting \(x^{k+1}\) with Equation (13) into \(z\) of Equation (11b) and \(u\) of Equation (12) updates the results in a relaxation form. Algorithm 1 presents an ADMM iteration for the ordered ridge regression of Equation (6).  
```
1:Initialize \(x^{0}\in\mathbb{R}^{p},z^{0}\in\mathbb{R}^{p}\), \(u^{0}\in\mathbb{R}^{p}\), \(\rho>0\)
2:while (\(\|\gamma^{k}\|_{2}\leq\epsilon^{pri}\) && \(\|S^{k}\|_{2}\leq\epsilon^{dual}\))do
3:\(x^{k+1}\leftarrow(A^{T}A+\rho*I)^{-1}(A^{T}b+\rho(z^{k}-u^{k}))^{T}\)
4:\(\lambda_{k}\ \ \leftarrow\)\(SortedLambda(\{\lambda_{k}\})\); \(\triangleright\) refer to migration \(z\)
5:\(z^{k+1}\leftarrow(\lambda_{k}+\rho*I)^{-1}\rho(ax^{k+1}+(1-\alpha)z^{k}+u^{k})\)
6:\(u^{k+1}\gets u^{k}+\alpha(x^{k+1}-z^{k+1})+(1-\alpha)(z^{k}-z^{k+1})\)
7:endwhile
```  
**Algorithm 1**Over-relaxed ADMM for the ordered ridge regression  
We observed that ADMM Algorithm 1 computes an exact solution for each subproblem and that their convergence is guaranteed by existing ADMM theory [24; 25; 31]. The most important and computationally intensive operation here is matrix inversion in line 3 of Algorithm 1. Here, matrix A is high-dimensional (\(p\gg n\)) and \((A^{T}A+\rho*I)\) takes \(\mathcal{O}(np^{2})\) and its inverse (i.e., \((A^{T}A+\rho*I)^{-1}\)takes \(\mathcal{O}(p^{3})\). We compute \((A^{T}A+\rho*I)^{-1}\) and \(A^{T}b\) outside loop; then, we are left with (inverse * \((A^{T}b+\rho(z^{k}-u^{k}))^{T}\)), which is \(\mathcal{O}(p^{2})\), while addition and subtraction take \(\mathcal{O}(p)\). \((A^{T}A+\rho*I)^{-1}\) is also cacheable, so the complexity is just \(\mathcal{O}(p^{3})+\text{k * }\mathcal{O}(np^{2}+p)\) heuristically with k number of iteration.  
**Generating the ordered parameter \((\lambda_{k})\):** As mentioned in the beginning, we set out to identify a computationally tractable and adaptive solution. The regularizing sequences play a vital role in achieving this goal. Therefore, we generated adaptive values of \((\lambda_{k})\) such that regressor coefficients are penalized according to their respective order. Our regularizing sequence procedure is motivated by the BHq procedure [27]. The BHq method generates \((\lambda_{k})\) sequences as follows:  
\[\lambda_{BH^{(k)}}=\Phi^{-1}(1-q*\frac{k}{2p})\] (14) \[  
value of \(q=0.055\). However, the goal is to obtain a non-increasing order of sequence \((\lambda_{k})\) by adjusting the value of \(q\), which stimulates convergence. Here, adjusting means tuning the value of the parameter \(q\) using the BHq procedure to yield a suitable sequence \((\lambda_{k})\) such that it improves performance.
# Enhancing Communication Security in Drones Using QRNG in Frequency Hopping Spread Spectrum
## 4 Methodology and System Architecture
### Enhanced Security Analysis  
The integration of true random frequency hopping introduces several security benefits. We analyze potential attack scenarios and discuss mitigation strategies.
## 5 5G FWA Field Trials
### Lessons Learned
#### 5.5.1 Cost-Effective Solution  
According to the IMT-2020 standard, 5G will be required to support a massive density of devices for every square kilometer. For instance, in Massive IoT (mIoT), a large number of IoT sensors and devices has to be supported for effective communication. To realize the network requirements, both fixed and mobile networks have to be densified. Due to the normally required trenches and other civil work, fiber densification in the last-mile network is uneconomical. Likewise, it is cost-intensive to expand and upgrade copper wireline infrastructure to fiber. FWA can be employed as an alternative solution to attend to the network densification in an economical manner. Furthermore, it can be an attractive broadband solution in areas with only copper or without wireline infrastructure in place. Furthermore, FWA can be employed to complement broadband service delivery in areas where there is insufficient fiber deployment [5; 6; 7].  
Moreover, considering the operating expenses in terms of maintenance costs and new services provision, the FWA solution is more beneficial. Nevertheless, the FWA OPEX regarding power consumption, rental, and spectrum licenses could be higher than that of FTTx. Furthermore, despite the fact that FTTx implementation can lead to a costlier solution, it offers several merits compared with FWA. One of such advantages is that FTTx is more reliable as it is not susceptible to weather or radio conditions [5; 6; 7].  
In general, note that FWA is not designed to be a total substitute to the wireline infrastructure. Each of the solutions has important tasks in the broadband service delivery for different applications. For instance, fiber infrastructure is highly appropriate in areas with concentrated customer density and backbone applications. On the other hand, FWA is a more economical scheme in the last mile compared to FTTx solution [5].
## 2 Materials and Methods
### Photodegradation Tests  
The DHP standard solutions were subjected to forced photodegradation shielded by the different types of glass. The experimental conditions inside the light cabinet were set in accordance with the conditions for the photostability tests described in ICH Q1B: UV-filter glass >290 nm, radiant power 350 W/m\({}^{2}\), corresponding to a dose energy of 21 kJ (min m\({}^{2}\))\({}^{-1}\). The temperature inside the cabinet was kept at 25 \({}^{\circ}\)C to minimize the increase of temperature due to the lamp. A fully automated flow system between the light cabinet and spectrophotometer was designed to avoid any interruption of the photodegradation test. For this aim, a peristaltic pump between the sample inside the irradiation cabinet and a flow-through cell placed in the spectrophotometer assured the continuous flow of the solution. The flow was fixed at 3 mL/min, and the UV spectra were recorded at 2 min intervals up to a total time of 140 min. To minimize any interference of extraneous light in the experiments, all laboratory procedures were performed in a room illuminated by a 60 W red lamp.
## 3 Results and Discussion
### Test and Evaluation of Hygroscopicity and Practical Moisture Buffering Performance
#### 3.2.3 Practical Moisture Buffering of Room  
By testing the change of air temperature and relative humidity in the room, the moisture buffering value of the building envelope material is further analyzed. As the test is conducted three months after the test room construction was completed, it is assumed that the impact of the moisture balance between different wall materials on the humidity distribution within the room can be ignored.  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Room**} & \multirow{2}{*}{**Parameter**} & \multicolumn{5}{c}{**Position**} & \multicolumn{2}{c}{**Non-Uniformity Coefficient**} \\ \cline{3-8}  & & **P2** & **P3** & **P4** & **P5** & **P6** & **Coefficient** \\ \hline \multirow{2}{*}{Room I (CM)} & Temperature (\({}^{\circ}\)C) & 13.8 & 14.1 & 16.5 & 14.2 & 14.1 & 0.0681 \\  & Relative humidity (\%) & 81.8 & 78.8 & 77.6 & 78.1 & 78.3 & 0.0189 \\ \hline \multirow{2}{*}{Room II (CHM-WSE)} & Temperature (\({}^{\circ}\)C) & 16.2 & 16.3 & 17.5 & 16.4 & 16.1 & 0.0309 \\  & Relative humidity (\%) & 73.3 & 72.3 & 70.2 & 72.3 & 73.2 & 0.0154 \\ \hline \hline \end{tabular}
\end{table}
Table 11: Non-uniformity coefficient. (Time: 8:30 the next day)  
Figure 21: Air moisture content in the center of the room.  
Figure 22: Indoor temperature and humidity distribution. (Time: 8:30 the next day).  
According to NORDTEST Project, the practical Moisture Buffer Value is presented using dimensions g/(m2 % RH)@8/16h which indicates the change of the mass of moisture in the material per free surface area and the step change of relative humidity during 8/16 h wetting/drying cycle. But it does not take into account other parameters that might influence the buffer performance, like moisture production and ventilation rates. According to the calculation results of moisture buffering performance (Table 12), it can be found that the CHM-WSE has good hygroscopic performance, while the CM has a relatively poor one. Meanwhile, the effect of moisture buffering in late spring is slightly better than that in winter.
# Segment Shards: Cross-Prompt Adversarial Attacks against the Segment Anything Model
## 4 Method
### Algorithms Analysis  
In this section, we present a comparative analysis of NPA, PA, SPA, and PBA algorithms, and, we attempt to explain the superiority of the PBA algorithm.  
As shown in Table 3, the differences between the algorithms are mainly reflected in five aspects, which are the use of the SAM structure, the use of prompt information, the loss function, the number of iterations, and the process affecting the momentum.  
\begin{table}
\begin{tabular}{l l l l l l} \hline \hline
**Algorithm** & **Used SAM Structure** & **Used Prompt** & **Loss Function 2** & **Number of Iteration 3** & **Momentum Affected by** \\ \hline NPA & \(g_{im}\) & No & \(L_{NPA}\) & K & No prompt \\ PA & \(g_{im}\), \(g_{pt}\), \(h_{dec}\) & \(p\) & \(L_{PA}\) & K & \(p,p,p,...,p,p,p\) \\ SPA 1 & \(g_{im}\), \(g_{pt}\), \(h_{dec}\) & \(p_{1^{*}}\), \(p_{2^{*}}\), \(p_{3}^{*}\) & \(L_{PA}\) & 3*K & \(p_{1^{*}}\), \(p_{1^{*}}\), \(p_{1^{*}}\), \(p_{2^{*}}\), \(p_{2^{*}}\), \(p_{2^{*}}\), \(p_{2^{*}}^{*}\), \(p_{3^{*}}\Among these aspects, the most essential is that different algorithms affect the momentum in different processes. In Figure 3, we show the intuitive impact of the different processes affecting the momentum. In gradient-based adversarial perturbation generation processes, momentum serves as a critical factor influencing the direction of perturbation generation. It can be succinctly understood that the introduction of varying information during the iterative process affects the direction of momentum.  
In the NPA algorithm, the direction of momentum is not influenced by any prompt information, thereby making it difficult for the generated adversarial examples to reach more universal prompt-dense regions (adversarial examples capable of successful attacks under a wider range of prompt conditions). In the PA algorithm, the direction of momentum is solely influenced by a single prompt, thereby significantly impacting the universality of the adversarial examples due to potential bias inherent in the specific prompt itself. In the PBA algorithm, the direction of momentum is continuously influenced by the combined effects of different prompt batch information, allowing the synthesis of multiple prompt information to correct the direction of momentum in a shorter period. Therefore, the momentum direction of PBA consistently approaches the correct direction. Conversely, in the SPA algorithm, despite having the same number of iterations and identical prompt information as PBA, it fails to promptly synthesize multiple prompt batch information to adjust the momentum direction. Consequently, the momentum direction of SPA remains unstable.  
In conclusion, adversarial examples generated by the PBA method consistently converge toward the correct direction, demonstrating superior generalization across different prompt conditions. This highlights PBA cross-prompt transferability.