esa-sceva/satcom-chunk-collection huggingface dataset:
# A Low-Profile Dual-Polarized Transmitarray with Enhanced Gain and Beam Steering at Ku Band
###### Abstract  
A low profile dual polarized transmitarray antenna, made of three identical layers, is proposed in this paper for Ku-band applications. The transmitarray comprises 22 \(\times\) 22 symmetrical unit cells. A 3-bit phase compensation layer with less than \(\alpha_{\rm T}\) = 1.3 dB transmission loss and 2\(\pi\) transmission phase coverage for both linear polarized components at the central frequency f\({}_{0}\) = 12 GHz is designed. Moreover, for an incidence angle \(\theta\) = 30\({}^{\circ}\), the unit cell transmission loss is less than 2 dB; the transmission phase is close to the transmission phase at zero incidence angle \(\theta\) = 0\({}^{\circ}\). The fabricated transmitarray exhibits a measured peak gain of Gm\({}_{0}\) = 21 dB at the frequency f\({}_{0}\) = 12 GHz. The corresponding measured 1 dB gain bandwidth is BWg = 10.8% (11.1-12.4 GHz). The measured peak side lobe levels are SLL\({}_{0}\) = \(-\)20.8 dB at f\({}_{0}\) = 12 GHz. The transmitarray antenna can be used for beam steering up to an angle of \(\gamma_{\rm max}\) = \(\pm\)30\({}^{\circ}\) with a measured scan loss \(\triangle\)GMSL1 = 2.73 dB at f\({}_{1}\) = 12.4 GHz.  
low profile; dual polarized; transmitarray antenna; 3-bit phase compensation; beam steering +
Footnote †: journal: Applied sciences  
Article
## 4 ACO Algorithm Path Planning and Improvement
### Comparative Analysis of Parameter Influence  
Set up two control groups, one is the traditional ACO and the other is the improved ACO. In the traditional ACO, the three parameters \(\alpha\), \(\beta\), and \(\rho\) are static values, while in the improved ACO, the three parameters \(\alpha\), \(\beta\), and \(\rho\) are dynamic values, as shown in Table 4.  
The experimental test questions are eil51 (51 cities) and att48 (48 cities) in TSPLIB. The parameters are 50 ants, 200 iterations, and an average of 10 runs. The results are shown in Table 5.  
The results show that in terms of path length. Improved ACO optimizes 2.9% and 3.3% on eil51 and att48, respectively, compared to traditional ACO. Improving ACO convergence speed reduces convergence algebra by 33%, and the additional computational overhead  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Parameter** & **Traditional ACO** & **Improve ACO** \\ \hline \(\alpha\) & \(\alpha=1.0\) & \(\alpha(N)=A\sin(N\pi/N_{\max})+C\) \\ \(\beta\) & \(\beta=2.0\) & \(\beta(N)=B\sin(2N\pi/N_{\max})+D\) \\ \(\rho\) & \(\rho=0.1\) & \(\rho(N)=\cos(N/N_{\max})\) \\ \hline \hline \end{tabular}
\end{table}
Table 4: Parameter setting.  
\begin{table}
\begin{tabular}{|c c c c c|} \hline \hline
**Algorithm** & **Path Length** & **Convergent** & **Computing** & **Path Length** & **Convergent** \\  & **(eil51)** & **Algebra** & **Time (s)** & **(att48)** & **Algebra** \\ \hline Traditional ACO & \(436.2\pm 5.7\) & 142 & 12.4 & 335.1 \(\pm\) 4.2 & 128 \\ Only dynamic \(\alpha\) & \(429.5\pm 4.9\) & 118 & 12.1 & 330.8 \(\pm\) 3.8 & 105 \\ Only dynamic \(\beta\) & \(427.8\pm 6.2\) & 156 & 12.7 & 328.4 \(\pm\) 4.5 & 140 \\ Only dynamic \(\rho\) & \(431.3\pm 5.1\) & 135 & 12.3 & 332.6 \(\pm\) 3.9 & 122 \\ Improve ACO & \(423.6\pm 3.8\) & 95 & 12.5 & 324.2 \(\pm\) 2.7 & 88 \\ \hline \hline \end{tabular}
\end{table}
Table 5: Important parameter test results.  
Figure 7: Improved ACO algorithm flowchart.  
introduced by dynamic parameters can be ignored in terms of computational efficiency (time difference < 2%). It can be proven that dynamic parameters perform consistently better than static parameters on multiple TSP.
## 4 The WBANs Communication Stack
### Medium Access Control Layer
#### 4.2.1 MAC Protocols Design Principles for WBAN  
Typically, several sensors connected on the body to monitor physiological as well as environment data layer to meet different time constraints according to various payloads (_i.e._, data rate). It also reflects un-even energy consumption from a WBAN network from the lifetime point of view. There is also a cross layer inter-dependency at the MAC level, as the nodes that have more data to transmit should have more access to the channel (such as more slots in a TDMA frame) to meet their time constraints and therefore will consume more energy. Similarly, specific network topology (_i.e._, star, one-hop or two-hop star for the intra-body, multi-hop for the inter-body and mesh for off-bodycommunication) also have impact on the MAC-layer design. In this regards, different medium access mechanism could be required such as TDMA for intra-body, hybrid access for inter-body and off-body communications. Before going into the details of the existing MAC protocols below section will highlight important design constraints for application-specific WBAN.
# Two-Layer-Graph Clustering for Real-Time 3D LiDAR Point Cloud Segmentation
## 3 Proposed Method
### Segmentation Standard
#### 3.2.2 Vertical Direction  
In the vertical direction, the work of point cloud clustering is mainly to merge different types of point cloud sets. For points belonging to different channels, we use the distance on the xy plane as the merge standard.  
\[Dis=\sqrt{(X_{1}-X_{2})^{2}+(Y_{1}-Y_{2})^{2}}>Th_{Dis} \tag{8}\]  
\(X_{1}\), \(X_{2}\), \(Y_{1}\), and \(Y_{2}\), respectively, represent the coordinate positions of point clouds belonging to different channels in the xy plane.
## 6 Engineering Applications
### Field Analysis and Follow-Up Measures  
After determining the parameters of anchor net spraying support and implementing the engineering application in MaKeng Iron Mine, under the influence of vibration of deep hole blasting in the quarry, the sprayed concrete layer close to the blasting point will be cracked, but no spalling phenomenon occurs. Due to the blasting disturbance, the service life of the roadway near the blasting point supported by sewing pipe type anchor net spraying is relatively short. In order to improve this situation, the mine adopts the method of filling after the stage mining room, and follows the principle of \"quick mining, quick exit, quick filling\" for the management of the quarry. By filling the hollow area in time, it effectively reduces the deformation and displacement of surrounding rocks around the hollow area, inhibits the further expansion of cracks in the shotcrete layer, and thus avoids the occurrence of concrete layer spalling. After the filling is completed, only the local cracked area needs to be shotcrete repaired to restore its integrity and ensure the long-term stability of the supporting structure. Practice shows that this method can significantly  
\begin{table}
\begin{tabular}{c c c c} \hline
**Displacement Value of** & **The Displacement Value** & **Top and Bottom Plate** & **Relative Convergence Rate (\%)** & **Rate (\%)** \\
**(mm)** & **(mm)** & **1.66** & **1.82** \\ \hline \end{tabular}
\end{table}
Table 6: Stability evaluation of mining roadway.  
improve the stability of the roadway surrounding rock, providing a strong guarantee for the safe production of the mine.
# Investigation of Hydrogen Flux Influence on InGaP Layer and Device Uniformity
## 3 Results and Discussion
### Impact of Total H\({}_{2}\) Flux on the Uniformity of InGaP/GaAs HBTs  
Based on the results of the experiment in the previous section, we focused on a specific hydrogen (H\({}_{2}\)) flux range, from 15,000 sccm to 19,000 sccm, to advance our investigation into the epitaxial growth of InGaP/GaAs HBT structures. This selection was aimed at thoroughly examining the influence of H\({}_{2}\) flux on the uniformity of our epitaxial wafers. Throughout these experiments, we adhered to strict growth parameters for the InGaP layer, as outlined in Table 2, while the conditions for the subsequent layers remained constant to guarantee the consistency and reliability of our findings. We successfully developed InGaP/GaAs HBT structures under various H\({}_{2}\) flux conditions. Following this, a standard processing protocol was applied to transform these epitaxial wafers into HBT devices. Notably, to directly assess the uniformity of the epitaxial layers, we sidestepped any processing steps, like device encapsulation, which might obscure our observations. The devices were measured in their raw form using a combination of a probing station and a semiconductor parameter analyzer. This direct approach allowed us to precisely evaluate epitaxial wafer uniformity, ensuring that our results were both accurate and reliable, providing a clear picture of the impact of H\({}_{2}\) flux on epitaxial layer consistency.  
Following the epitaxial growth of InGaP/GaAs HBT structures and device fabrication, we embarked on an in-depth evaluation of the epitaxial wafer's uniformity. To achieve this,  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Sample No.** & **H\({}_{2}\) Flux** & **Growth Temperature** & **V/III** \\ \hline Sample-1 & 19,000 sccm & & \\ Sample-2 & 17,000 sccm & 650 \({}^{\circ}\)C & 80 \\ Sample-3 & 15,000 sccm & & \\ \hline \hline \end{tabular}
\end{table}
Table 2: Growth conditions for the InGaP layer across all samples within the complete HBT epitaxial structure.  
we conducted extensive measurement and analysis across the wafer. We chose five points, ranging from the center to the edge, labelled 1 to 5, each representing a specific device position for measurement. The specific measurement positions are shown in Figure 3. Our examination focused on key electrical performance metrics, including Gummel, IV, and breakdown voltage measurements. The comprehensive assessment of these measurements, comparing results from all selected points, allowed us to gauge the epitaxial wafer's uniformity accurately. Consistent and stable outcomes across these metrics would indicate a high level of uniformity in our InGaP/GaAs HBT epitaxial wafers. Such uniformity is pivotal for the successful production of high-performance HBT devices, underscoring the effectiveness of our epitaxial growth process in achieving uniform wafer characteristics.
## 3 Cellular Network Modeling
### LTE Networks  
The conceptual schema for LTE networks, depicted in Figure 5, shows its simplified organization.  
Administratively, the cells are grouped in tracking areas (TAs), each one identified by its _lac_ withing the PLMN. The combination of these identifiers is called _tai_ (_mcc+mnc+lac_). The attribute _tai_, combined with the _oci_, globally identifies each cell (administrative identifier, chosen in the diagram).  
Indeed, the radio access network (EUTRAN) includes only one component modeled by the entity eNodeB and identified by the attribute _eNB-id_ within its PLMN. Each eNodeB controls one or more cell. Finally, considering the local physical identifier, for each LTE cell we have the composition of _pci_ and _earfcn_.
# A Deep Learning Approach for Network Intrusion Detection Using a Small Features Vector
## 6 Discussion  
The proposed research utilized the same features as those used in [13]. It is clear from Table 5 that the proposed model, which employed an FFNN classifier, achieved higher accuracy compared to the decision tree (DT) and k-nearest neighbor (KNN) on both datasets. This is due to the inherent feature extraction ability of the FFNN. Conversely, in [11], all features were given to the deep neural network (DNN) classifier resulting in lower accuracy on both datasets. This is due to the absence of any feature selection method that could identify and retain only the important features while removing the unimportant features. This research confirms that all features are not useful, and a model's performance improves, when we use a small feature vector consisting only of features with predictive power. Using a small feature vector also requires less processing power.
# Fractional Flow Reserve (FFR) Estimation from OCT-Based CFD Simulations: Role of Side Branches
## 4 Limitations  
The curvature of the arteries is not considered in the current geometry reconstruction process, which may deviate the FFR computations. However, previous studies reported minor effects on FFR caused by the curvature of the coronary arteries [39; 40]. For more accurate computations, 3D curved vessel geometry can be reconstructed by placing the OCT-segmented lumen cross sections in the 3D curvature of the artery derived from different angiographic views [41; 42]. The side vessels are manually segmented and connected to the main vessel, where very small branches (<0.5 mm) were ignored. The errors in segmented side branch diameters, angles, and locations may deviate the flow distribution into side branches. However, these errors are likely to cause a minimum effect on FFR computation and have less impact on the FFR comparisons in the study. More accurate segmentation of the side branches can be achieved by the fusion of OCT images and angiography views [27] or through automated segmentation methods [34]. The microvascular resistances of the side branch outlets were calculated by assuming a structured tree model [20] connected to the outlets. While these resistance values are likely to vary from the realistic patient-specific microvascular resistances, they provide a reasonable approximation for the aim of the study, exploring the effect of side branch flow on FFR. The study only incorporated two patient-specific vessel models to evaluate the conclusions derived from the idealized models. However, the qualitative findings are expected to remain the same. Analysis of FFR in more patient-specific vessels will further strengthen the findings of the study.
## 1 Introduction  
Evaluation of ACL Graft Remodeling and Prediction of Graft Insufficiency in Sequenced MRI--Two-Year Follow-Up  
**[PERSON] 1,2,*\({}^{\text{(\text{\text@underline{\text{\text{\text@underline{\text{\text{\text@underline{\text{\text{\text@text@text@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@  
## 1 Introduction  
Anterior cruciate ligament (ACL) rupture causes knee instability, which affects sport activities and increases the risk of meniscal injury and early osteoarthritis [1]. ACL reconstruction reduces anterior tibial laxity but does not fully restore normal tibiofemoral kinematics [2]. Despite efforts and significant advances in ACL reconstruction, clinical failures continue to occur [3]. It is still debated among researchers and clinicians on what processes are involved in ACL graft healing and remodeling and how long these processes take in patients [4]. This information is crucial for patients to return to sports activities.  
[PERSON] et al. [5] performed a systematic review of literature on the \"ligamentization\" process of human ACL graft. He showed that a free tendon graft used for ACL reconstruction undergoes a series of biologic processes called \"ligamentization\". Ligamentization may be divided further into the early phase, remodeling, and maturation of the graft. The graft shows viability throughout the whole process. In histopathologic evaluation, the graft resembles a normal intact human ACL. However, specific differences exist between the phases. In addition, there is no consensus for the exact time frames for each stage of the ligamentization process.  
[PERSON] et al. [6] proved that volume and greyscale values are predictive of the healing graft's structural properties in his preclinical animal model studies. He also showed magnetic resonance imaging (MRI) parameters may predict biomechanical properties and outcome measurements in human patients after ACL reconstruction [7]. [PERSON] et al. [8] also showed in an animal model that quantitative evaluation of MRI might be a useful tool for following the graft remodeling. [PERSON] et al. [4] proved that implanted grafts could transform into native ACL-like tissue with a similar ultrastructure and metabolism.  
The aim of our study was to evaluate the bone-patellar tendon-bone (BPTB) ACL graft remodeling process in our group of patients. We used previously described techniques to evaluate their efficacy. Our results were correlated with variables including age, sex, and weight-bearing. Additionally, for the first time to our knowledge, we correlated the graft remodeling process not only with clinical outcome, but also with indirect MRI signs of ACL graft insufficiency. We also analyzed standard deviation of SI as a separate value.
## 2 Results and Discussion
### Enzymatic Assay of Crude VMPSTS  
Functionality of the recombinant VMPSTS of both crude and purified recombinant protein extracts were analyzed by enzymatic assay using two different assay buffers. However, both buffer systems yielded comparable results with no significant differences. When the crude proteins of VMPSTS and the negative control were used for the enzymatic assay, majority of the FPP were converted to farnesol which gave the highest peak (data not shown) potentially by non-specific endogenous phosphatases, even when sodium tungsten and sodium fluoride were added to the assay as phosphatase inhibitors. Phosphatases have been reported to metabolize FPP to produce farnesol [25]. Apart from the non-specific phosphatase activity on FPP, it was reported that FPP was prone to non-enzymatic hydrolysis to nerolidol and farnesol when Mg\({}^{2+}\) was present whereas in the presence of Mn\({}^{2+}\), the hydrolysis product was almost exclusively nerolidol [26]. These cations are common co-factors for enzymes including terpene synthases and hence, precaution should be taken to rule out possibilities of products formed from such non-enzymatic hydrolysis of FPP in the terpenoid product profiles. Indeed, this was also observed in our study when FPP was incubated with the assay buffer without any protein extracts. Due to the high amount of farnesol which was produced when using crude protein extracts, only trace amounts of other sesquiterpenes which may be true products of VMPSTS were detected with peak areas \(<\)6% of the farnesol peak (Figure 3). Copaene and \(\delta\)-cadinene peaks were observed at retention times (RT) 6.43 min and 6.94 min respectively and exclusively in assays performed with crude VMPSTS (Figure 3). Although peaks at RT 6.62 min, 6.71 min and 6.84 min observed from the VMPSTS crude protein also corresponded to sesquiterpene products and were identified as farnesene, aromadendrene and germacrene D respectively, peaks with similar retention times were also present in the negative control. Interestingly, a comparison of the negative control mass spectra to the NIST and  
Figure 2: SDS-PAGE analysis showing crude (**A**) and his-tag purified (**B**) protein extracted from clones harboring the pNZ:VMPSTS plasmid. Clones were grown and induced with 40 ng/mL nisin for 2 h. Lane M: PageRankTM Sustained Protein Ladder; C: Crude total protein extract; P: His-tag purified VMPSTS protein at 63 kDa.  
Wiley libraries identifies the peak at RT 6.62 min as nerylacetone in comparison with farnesene in the VMPSTS crude protein and negates both peaks at RT 6.70 min and 6.84 min as sesquiterpenes, but identifies them as 1-dodecanol and methyl 4,4,7-trimethyl-4,7-dihydroandan-6-carboxylate instead.
## 4 Conclusions  
This work provided the necessary support for the direct growth of cobalt oxide on FTO thin films, the effect of annealing on the phase transformation of cobalt oxide, and the effect of electrolyte on the PEC water-splitting application. The annealing temperature affected the phase of cobalt oxide thin films and changed the morphology from microflower Co\({}_{3}\)O\({}_{4}\) to urchin-like Co\({}_{3}\)O\({}_{4}\)/CoO mixed phase. A single phase of CoO could not be produced by direct growth on FTO through the hydrothermal method due to the sensitivity of FTO to temperatures higher than 550 \({}^{\circ}\)C. In addition, the electrolyte affected the performance of PEC water splitting. H\({}_{2}\)SO\({}_{4}\) resulted in a higher photocurrent density than Na\({}_{2}\)SO\({}_{4}\) and KOH. According to the measured photocurrent generation, the highest value was contributed by the single-phase sample of Co\({}_{3}\)O\({}_{4}\) from the annealed at 450 \({}^{\circ}\)C. The stability test also showed that the Co\({}_{3}\)O\({}_{4}\) from the annealed at 450 \({}^{\circ}\)C is more stable than the mixed-phase produced by the annealed at 550 \({}^{\circ}\)C. This study found that the bandgap and band edges of the cobalt oxide thin films produced from the direct hydrothermal method slightly different from the powder results, in which powder cobalt oxide produces a more appropriate band structure to the PEC water-splitting application.  
Conceptualization, K.A.; methodology, K.A. and S.N.F.M.; investigation, S.N.F.M.; formal analysis, S.N.F.M., M.N.I.S. and K.A.; resources and supervision, K.A., L.J.M., M.B.K.; writing--original draft preparation, S.N.F.M.; writing--review and editing, K.A. All authors have read and agreed to the published version of the manuscript.  
This research received funding from The Ministry of Education, Malaysia, through the FRGS/1/2019/STG01/UKM/03/2 Research grant and Universiti Kebangsaan Malaysia for Publication Acceleration Fund PP-SELFUEL-2020.  
Not applicable.  
Data Availability StatementData is contained within the article.  
The authors declare no conflict of interest.  
Figure 8: Band alignment of Cobalt Oxide thin film annealed at 450 \({}^{\circ}\)C and 550 \({}^{\circ}\)C against potential redox of water molecule.