esa-sceva/satcom-chunk-collection huggingface dataset:
## 3 Results and Discussion
### Macrostructure Examination  
Photographs of the SS304L/IN718 ST and SS304L/IN718 STA dissimilar friction welded joints are depicted in Figure 6a,b, respectively. A macrograph of the friction-welded dissimilar joint of SS304L/IN718 ST is shown in Figure 7. The macro examination revealed a defect-free weld joint, with a sound flash caused by the plasticization of the metal at the weld interface. The formation of the flash on both sides was lopsided, due to the different mechanical properties of the dissimilar materials being joined [22]. On the 304L side, the weld flash was dominant, whereas the Inconel 718 had a less pronounced effect on the flash formation, indicating that SS304L was more deformed at a high strain at the weld interface [23]. This was because IN718 is much harder than SS304L at friction welding temperatures [24]. Furthermore, a sharp reduction in the flow stress in the SS304L at high temperatures during friction welding softened the alloy compared to the IN718 side. Moreover, the SS304L's poor thermal conduction characteristics compared to the IN718 led to the rapidly rising temperature on its side of the joint.
# Pilot-Assisted OFDM for Underwater Acoustic Communication
## 2 State of the Art Research
### Pilot-Based Channel Estimation  
In the wireless domain, pilot-based estimation has long been used with multicarrier systems such as OFDM. In the UWA channels, several estimation algorithms have also been proposed when using OFDM systems. In the following, we present an overview of the work recently undertaken in this domain, mainly for UWA channels.  
An adaptive channel estimation technique was proposed in [13] for a MIMO-OFDM system. In this work, a least squares estimation algorithm was used along with a block-adaptive method. This had the additional advantage of avoiding the computational complexity of a matrix inversion. The accuracy of the proposed algorithm depended upon its ability to determine the channel parameters from the pilot estimates of the previous block. An algorithm that inserted multiple pilots in an OFDM system to estimate the UWAchannel was investigated in [14]. The authors employed three types of pilots, namely, comb, block, and scatter. It was shown that the scatter type of pilots gave the best performance in terms of robustness against the time selectivity and frequency selectivity of the channel. In [15], a deep neural network (DNN) was trained on estimated pilot symbols. The trained network was then used to estimate the impulse response of the underwater channel. A simulation testbed that used OFDM for a UWA communication system was presented by [PERSON] et al. [16]. The results were reported for two channel estimation techniques, namely, LSE and MMSE. A channel estimation scheme designed for radio frequency CP-OFDM that used LSE was presented in [17]. The authors also compared the estimated channel with a real channel. Using pilots for an adaptive estimation of the UWA channel, a recursive least squares algorithm was proposed in [18] to estimate the channel for a MIMO-OFDM system. Moreover, a maximum likelihood decoder was employed to estimate the transmitted data. In another publication [19], the authors used multiple channel sensing and estimation techniques to capture the time-varying behavior of a UWA channel.
# Optimization Techniques for Design Problems in Selected Areas in WSNs: A Tutorial
## Part II Overview on Mathematical Optimization  
This part of the paper serves as the fundamentals of optimization techniques, required for being able to use optimization techniques in any WSN design as part III shows. The purpose of this part (part II) is to give a basic tutorial on optimization techniques. Section 1 provides a brief overview on the history of operations research. Section 2 provides an introduction to optimization and the different classes of optimization problems. Section 3 is focuses on linear programming, which is the first type of optimization that was considered in the optimization literature and whose concepts form the foundations of more advanced optimization problems. The simplex algorithm, linear duality, Karmarkar's algorithm, dual simplex as well as a discussion on computational efficiency of simplex and Karmarkar's algorithm are all provided in Section 3.  
Section 4 discusses a special class of linear programs that is very important for WSNs. This type of problems is known as the _network flow problems_ and the _minimum spanning tree_ MST problem. Section 4 also presents examples on how these types of problems and their extremely efficient algorithms can be used in WSN design problems. Section 5 provides an introduction to non-linear programming (NLP), which is a very vast field of optimization problems. We discuss fundamental concepts like Lagrange functions and multipliers, KKT conditions, convexity, duality in NLPs etc. These form the basis of any algorithm design designed to solve an NLP. A taxonomy of the different solution methods used in NLP is presented in a summarizing figure. The details of each are beyond the scope of this paper though.  
Finally, Section 6 presents primal and dual decomposition schemes for solving optimization problems, which enable us to break problems that are, partially decomposable except for a subset of complicating constraints or variables. Hence, a large problem can be broken down into a number of smaller subproblems and a master problem that can be solved separately in iterative fashion in a distributed scheme. Distributing the computations for the optimization problem across a large number of sensors yields alleviates the computational effort (and corresponding battery energy) that a single sensor node will expend in a centralized scheme.
# Machine Learning Based Energy-Efficient Design Approach for Interconnects in Circuits and Systems
## 4 Analysis Results
### Single-Ended Microstrip Line
#### 4.1.3 Eye Diagram and \(V_{tx}\) Reduction in Time Domain  
The induced crosstalk noise voltage is the product of the voltage in the adjacent channel and the FEXT coefficient. While the FEXT coefficient depends on the difference between capacitive and inductive coupling related to the distance between signals, the signal propagation including even and odd mode specifies the value of the voltage between adjacent channels. The even and odd modes happen when the data polarity in two proximity channels are same or opposite to each other, respectively. On the other hand, the subtraction of the far-end crosstalk voltage to the primary channel voltage leads to the worst-case eye diagram. Consequently, the signal propagation mode and the distance between the lines have significant impact on the worst-case eye diagram. In addition, if the channel width is larger than that of optimal design, impedance mismatches can happen. The eye-diagram simulation results with 1.0V \(V_{TX}\) at a 10 GHz data rate are shown in Table 3 and the eye diagram of the optimal design at minimum allowable \(V_{TX}\) is shown in Figure 8.  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multicolumn{1}{c}{**W**} & \multicolumn{6}{c}{**25 \(\mu\)m**} \\ \hline \(K_{D}\) & 1.0 & 1.5 & 2.0 & 2.5 & 3.0 & 3.5 & 4.0 \\ \hline \(EH_{normal}\) & 359.7 & 276.3 & 384.2 & 357.4 & 324.2 & 358.0 & 366.6 \\ \hline \(EH_{addmade}\) & 306.8 & 255.1 & 376.9 & 361.3 & 323.8 & 368.4 & 380.6 \\ \hline \(EH_{recumode}\) & 336.9 & 267.5 & 333.6 & 295.0 & 279.8 & 309.9 & 302.3 \\ \hline \(EH_{averstcase}\) & 306.8 & 255.1 & 333.6 & 295.0 & 279.8 & 309.9 & 302.3 \\ \hline \(V_{TX}\) for min EH & 0.82 & 0.98 & 0.75 & 0.85 & 0.89 & 0.81 & 0.83 \\ \hline \hline \end{tabular}
\end{table}
Table 3: Eye diagram simulation results of the microstrip line.  
Figure 7: S-parameter prediction for the optimal structure W = 25 \(\mu\)m, \(K_{D}\) = 2.  
The simulation results illustrate that the optimal structure suggested by the ANN model has the largest worst-case EH in comparison to others. Moreover, this one with the smallest \(V_{TX}\) of 0.75 V can achieve the minimum EH requirement (250 mV). The 25% allowable \(V_{TX}\) reduction for this structure is also the greatest among the others. Hence, this structure satisfies the EH requirement with the smallest \(V_{TX}\) leading to the minimum power consumption.
# Assessment of Cardiovascular Disease in Autosomal Dominant Polycystic Kidney Disease
## 10 Myocardial Scintigraphy
### Clinical Implications  
Cardiovascular problems are a major cause of morbidity and mortality in ADPKD patients. Hypertension occurs in 50-70% of patients before the reduction in glomerular filtration at an earlier age than the general population, and it is associated with an increased rate of progression to ESRD [1,2]. Additionally, LVH occurs frequently and has important roles in cardiovascular complications in patients with ADPKD. Moreover, endothelial dysfunction, biventricular diastolic dysfunction, increased carotid intima-media thickness, and impaired coronary flow velocity reserve are present even in young ADPKD patients with normal blood pressure and well-preserved renal function [3,5,43]. Coronary and cerebral aneurysms and dissections represent a source of coronary syndromes and death in ADPKD. Clinical disparities may suggest a different mechanism of aneurysm formation compared to the population without ADPKD; in fact, the genetic mutations of ADPKD may predispose individuals to coronary abnormalities, especially aneurysms.  
These findings suggest that cardiovascular involvement starts very early during ADPKD. Intracranial and extracranial aneurysms and cardiac valvular defects are other potential cardiovascular problems in patients with ADPKD. The early diagnosis and treatment of hypertension with drugs that block the renin-angiotensin-aldosterone system have the potential to decrease the cardiovascular complications and slow the progression of renal disease in ADPKD.
## Abbreviations  
* DEM [2010] DEM Digital elevation model FEMA Federal Emergency Management Agency HDCM Horizontally divided channel method LiDAR Light detection and ranging MAE Mean absolute error NSE Nash-Sutcliffe efficiency index PNOA Plan Nacional Orto-fotografia Aerea (Aerial Ortho-photography National Plan) SNCZI Sistema Nacional de Cartografia de Zonas Inundables (Food Prone Areas Mapping National Plan) VDCM Vertically divided channel method
## 3 Results and Discussion
### The Removal Effect of the Mixed Filter Material
#### 3.2.1 The Turbidity Removal Effect  
Figure 7 shows the turbidity removal effect of single volcanic rock and coconut shell activated carbon filter media and their mixed filter media over 36 days. In the initial stage of operation, the mixed filter material with a mixing ratio of 3:1 (Reactor 6\({}^{\#}\)) had the best turbidity removal effect compared with other mixed filter materials (Reactors 4\({}^{\#}\) and 5\({}^{\#}\)), with a removal rate of 92.71 \(\pm\) 0.42%. Previous studies have found that among single filter media, Reactor 2\({}^{\#}\) has the best turbidity removal effect. Through comparison, it was found that the average removal rate of Reactor 6\({}^{\#}\) was 1.25 percentage points higher than that of Reactor 2\({}^{\#}\). Although the mixture of volcanic rock and coconut shell activated carbon filter material forms a multi-level pore structure, which enhances the filtration and retention effect of the filter material and improves its removal effect, this difference is masked by the standard deviation of the two, indicating that the performance boundary of a single filter material has not been significantly broken through. This is due to the fact that the porous structure of volcanic rock and the high specific surface area of activated carbon do not produce an effective complementary effect. After 26 days of operation of the BSF reactor, the turbidity removal rate reached a stable state. Reactor 6\({}^{\#}\) has the best turbidity removal effect, which is 0.09 percentage points higher than that of Reactor 2\({}^{\#}\). Similarly, this difference is covered by the standard deviations of the two, indicating that it does not significantly exceed the performance boundary of a single filter material. This is due to the fact that the porous structure of volcanic rocks and the high specific surface area of activated carbon do not effectively complement each other, and also to the influence of the uniformity of microbial community distribution.
###### Abstract  
This article focuses on power electronic multi-pulse 12-, 24- and 36-impulse rectifiers based on multi-winding rectifier transformers. The effectiveness of voltage processing with different variants of supply voltage sources is discussed and arguments are formulated for limiting oneself to 24-pulse processing, which is used in the latest technological solutions of modern aviation technology. The main purpose of this article is to conduct a study (analysis, mathematical models, simulations) of selected multi-pulse rectifiers in the context of testing their properties in relation to the impact on the electrified power supply network. The secondary objective of the article is to assess the possibility of using Matlab/Simulink to analyze the work of rectifier circuits implemented in aircraft networks compliant with the more/all electric aircraft (MEA/AEA) concept. The simulation tests included designing a typical auto-transformer rectifier unit (ATRU) system in the Simulink program and generating output voltage waveforms in this program in the absence of damage to the rectifier elements. In the final part of this work, based on a critical analysis of the literature on the subject of the study, simulations were made of exemplary rectifiers in the Matlab/Simulink programming environment along with their brief analysis. Practical conclusions resulting from the implementation of the MEA/AEA concept in modern aviation were formulated.  
examination; multi-pulse rectifiers; energy-electronic power system (PES); more/all electric aircraft +
Footnote †: journal: Applied Sciences
# Improving Performance of Cluster Heads Selection in DEC Protocol Using K-Means Algorithm for WSN
## 4 DEC-KM (Deterministic Energy-Efficient Clustering Protocol with K-Means)
If there are no more nodes in the cluster area, eliminate the cluster with the node energy below the given threshold and assign its nodes to the closest cluster heads.
# Exploiting Data Similarity to Improve SSD Read Performance
## 5 Experiment
### Results and Analysis
#### 5.2.3 Proportion of Read and Write Requests That Are Redirected  
We evaluated the percentage of redirected read and write requests, as depicted in Figure 13. Redirected requests refer to those where the target PPN is occupied, causing the system to read data from alternative candidate PPNs in the mapping table. As mentioned in the previous subsection, the webmail workload contains a significant amount of duplicate data with the same LPN. To address this, DS-FTL assigns these duplicate data to different planes and reads them from the candidate physical address, resulting in relatively higher redirected read and write request ratios of 15.6% and 29.2%, respectively. On the other hand, the home3 workload exhibits a smaller number of read and write requests, leading to lower probabilities of data duplication within the same plane. Consequently, the final redirected read and write ratios for the home3 workload are smaller, at 1.46% and 1.48%, respectively. In general, workloads with a higher occurrence of duplicate data and a greater  
Figure 11: Data redundancy rate under different allocation schemes.  
Figure 12: Duplication rate of home2 in each plane.  
number of write requests tend to have a higher proportion of redirected read, while the proportion is lower for other scenarios. Overall, the average percentage of redirected read and write requests across all eight workloads is 8.21% and 10.5%, respectively.
## 5 Discussion
In addition, they suggested there is an association between the severity of the left ventricular mass and periodontitis in participants with essential HTN. We believe that these inconsistent results can be due to differences in the presence or absence of cardiovascular disease such as HTN. In our study, CPI or periodontal disease were positively associated with PP levels (\(\beta\), 0.128; 95% CI, 0.033-0.066) or high PP (OR, 1.921; 95% CI, 1.512-2.444) in the overall population (Tables 3 and 5). However, when non-HTN and HTN groups were analyzed separately, the results for each group were different. In the HTN group, CPI or periodontal disease were positively associated with PP levels (\(\beta\), 0.173; 95% CI, 0.034-0.087) or high PP (OR, 2.131; 95% CI, 1.579-2.876). However, in the non-HTN group, the associations of CPI or periodontal disease with PP levels (\(\beta\), 0.041; 95% CI, -0.003-0.045) or high PP (OR, 0.866; 95% CI, 0.494-1.518) were not significant. Compared to normotensive populations, periodontitis in hypertensive populations can show alterations in endothelial and increased cardiovascular risk [33]. A decline in endothelial function is closely related to increases in aortic stiffness and PP [34]. On the contrary, the adverse effect of hypertension on periodontal tissues cannot be excluded. Alterations in microcirculation in subjects with HTN can lead to periodontal ischemia, which can cause periodontal disease [35]. PP is a predictor for atherosclerosis, coronary heart disease, and left ventricular hypertrophy, but may have poor predictive function with normotensive blood pressure. In the Systolic Hypertension Test in the Elderly Program trial, every 10 mmHg increase in PP in the HTN group increased the risk of heart failure by 32% and stroke by 24%; however, the incidence of coronary heart disease was not associated with PP in either the non-HTN or HTN groups [36]. In addition, [PERSON] et al. reported that elevated PP is strongly associated with carotid atherosclerosis in patients with HTN, but not in those with normal blood pressure [37]. The mechanism underpinning the association of periodontal disease and PP in population with HTN has not yet been established. However, in patients with HTN, hypertrophic heart and periodontal disease may share arteriolar and capillary rarefaction and microcirculatory dysfunction [38; 39]. Pressure overload causes left ventricular hypertrophy to develop, which can narrow the lumen diameter of microvessels [40]. The limitation of the present study was that its cross-sectional design made it difficult to establish a causal relationship between PP and periodontal disease in the hypertensive population. Nevertheless, this study is the first reported study to determine the association of periodontal disease and PP in Korean adults with hypertension. Therefore, if a cohort study of their relationship was conducted, more generalizable and accurate results might be obtained.
## 3 Materials and Methods
### Extraction and Analysis of Lipophilic Compounds  
#### 3.3.1 Extraction and Analysis of Terpenoids and Policasonols Using GC-qMS  
Lippphilic compounds, such as policosanols, tocopherols, and phytosterols, were extracted following the method of [PERSON] et al. [41]. Briefly, 100 mg of pigmented rice powder were transferred to 15 mL tubes. For the extraction, ascorbic acid (3 mL; 0.1%, _w/v_) in ethanol was added, with 0.05 mL of 5\(\alpha\)-cholestane (10 \(\mu\)g/mL in hexane) as an IS. The samples were vortexed for 20 s, and incubated in a water bath at 85 \({}^{\circ}\)C for 5 min. Saponification with potassium hydroxide (120 \(\mu\)L; 80%, _w/v_) was conducted in a water bath at 85 \({}^{\circ}\)C for 10 min. The mixture was then immediately placed on ice for 5 min. It was then treated with hexane and deionized water (1.5 mL each), and centrifuged at 4 \({}^{\circ}\)C and 1200\(\times\)\(g\) for 5 min. The upper layer was pipetted into a new tube and re-extracted with hexane (1.5 mL). The hexane fraction (approximately 3 mL) was dried under nitrogen gas, and then concentrated in a centrifugal concentrator (CC-105, TOMY, Tokyo, Japan). For derivatization, MSTFA (30 \(\mu\)L) and pyridine (30 \(\mu\)L) were added, and the samples incubated at 60 \({}^{\circ}\)C for 30 min, with shaking at 1200 rpm. The obtained lipophilic compounds were analyzed using a GC-MS QP2010 Ultra system equipped with an AOC-20i auto sampler (Shimadzu, Kyoto, Japan). For the analysis, 1 \(\mu\)L of the extracted sample was injected into a Rtx-5 MS column (30 m \(\times\) 0.25 mm \(\times\) 0.25 \(\mu\)m; Restek, Bellefonte, PA, USA) at a 1:10 ratio split mode. The carrier gas was helium, flowing at a constant rate of 1.00 mL/min. The front inlet temperature was 290 \({}^{\circ}\)C. The initial oven temperature of 150 \({}^{\circ}\)C was held for 2 min, then ramped to 320 \({}^{\circ}\)C at 15 \({}^{\circ}\)C/min, and maintained for 10 min. The ion source and interface temperatures were 230 \({}^{\circ}\)C and 250 \({}^{\circ}\)C, respectively. The mass spectra range for scanning was 85 to 600 _m/z_, and the ions were detected in selected-ion monitoring (SIM) mode for peak analysis. Chromatographic data were processed using the Lab solutions GC-MS solution software (version 4.11, Shimadzu, Kyoto, Japan). For qualitative and quantitative analysis of the lipophilic compounds, calibration curves were prepared using lipophilic standards (Tables S4 and S10).
# Advances of UAVs toward Future Transportation: The State-of-the-Art, Challenges, and Opportunities
## 4 Potential Research Directions
### Limitations in Information  
Future ITS is a complex domain of research that is still under investigation. Although extensive development has been made in this area, the amount of available information is limited as most system components are still not implemented widely. Many researchers have proposed the layering of the system, which provides an idea of the UAV-based future ITS. As it is not implemented yet, many limitations and challenges are still unknown. It is difficult to assume the everyday challenges of UAV implementation in future ITS. There will be a lot of unforeseen risks, as well as opportunities. More experiments implementing UAV applications in ITS can be explored in future research.  
With the advancements in global technology, the overall current transportation system is indeed changing towards the ITS concept. As UAVs are one of the essential elements of future ITS, significant improvements, retrofits, and upgrades must be made in the current transportation system infrastructure. These efforts require rigorous research and experiments of UAVs on a smaller scale prior to the actual implementation. Popular research areas that are currently under investigation are UAV-assisted ITS, data routing and communication, energy-efficient ITS, load transportation, and emergency response.  
Although significant technology development of incorporating UAVs in ITS has been observed, other areas such as policies, management, and security issues need to be investigated to achieve the ultimate goal of employing UAVs in the future ITS. This study provides an overview of the current state of the art and directs toward future development. The identified challenges can help both the transportation researchers and the Department of Transportation (DOT) understand the underlying improvements necessary for the ITS development.