esa-sceva/satcom-chunk-collection huggingface dataset:
# SMS: A Secure Healthcare Model for Smart Cities
## 2 Need for Transition from Cloud to Edge in a Smart City Ecosystem  
The penetration of IoT in everyday lives for providing smarter solutions has resulted in the generation of large volumes of data. With such large volumes of data at our disposal, cloud computing (CC) has emerged as one of the preferred choices for IoT solutions. Cloud computing became jargon in the year 2006, when it was introduced to the world. The term cloud computing further gained popularity in the following years after it was widely used by the tech giants like Amazon, Microsoft, IBM, etc.  
The two technological breakthroughs of the modern world, i.e., IoT and cloud computing, have always complemented each other for efficient results. However, the centralized structure of cloud computing has proven to be a limitation for providing solutions in cases where components are geographically dispersed. Edge Computing (EC) was born to meet this challenge by allowing some of the processing to be done at the network nodes that can be either \"centralized\" or \"distributed\" or at the \"end of the network,\" creating the \"edge nodes\" and contributing to distributed processing. Since its inception in 2005, cloud computing has emerged as a breakthrough technology that brought transformational changes in the way business were run. CC has provided an efficient and cost-effective way to store and process the data in a centralized cloud repository. However, the centralized storage structure is not able to keep up with the increasing demand for the real-time processing of data [9; 10; 11]. To address this increasing demand for minimizing the latency, edge computing can provide potential solutions by providing processing capabilities at the \"edge of the network\", thus minimizing the overhead caused by the speed of the data transformation and latencies [12; 13; 14].
## 2 Data Modulation in NAND Flash
Interleaving is to swap the places of the message bits in the frames before modulating them to voltage levels. Correspondingly, a deinterleaving module is applied to restore the swapped message bits after the frames are retained. In our implementation, we built a uniformly randomly generated lookup table to allocate each bit to a specific position and the same lookup table will be used for all frames. For example, message bit 1 is allocated to position 5, bit 2 is allocated to position 11, and so on. Figure 1: (a) A example of read reference voltages in triple-level cell (TLC) with 1/2 gray coding modulation; (b) how the data is demodulated from a TLC NAND flash cell. The interleaving aims to spread the message bits evenly across the memory cells. The deinterleaving restores the original order of the message bits by using the lookup table reversely. For instance, the bit in position 5 is back to message bit 1, and the bit in position 11 is back to bit 2, and so on. The interleaving scheme is not unique, one can apply other interleaving schemes for his own design purposes. The effect of interleaving depends on the length of the interleaved message bits and can be measured with the variance of FERs. As shown in Figure 4, the effect is better when the interleaved message bits become longer, but the variance drops slowly when the length exceeds 500 and almost no longer drops when the length exceeds 1200. Considering that the longer interleaving requires larger read-only memory and takes more clock cycles, which will increase the hardware complexity and extend processing time, it is recommended that interleaving a message in every 1024 bits is sufficient. As shown in Figures 5 and 6, for both types of data modulation, interleaving makes the disturbed bits evenly distributed to each frame and turns the increasing rates of FERs from each page to almost the same. Figure 4: The variance of page error rates vs. lengths of interleaved messages bits tested at RBER = 0.01. Figure 5: FERs of frames from different pages using 1/2 gray coding modulation with interleaving. Figure 6: FERs of frames from different pages using balanced gray coding modulation with interleaving.
# Ramjet Nozzle Analysis for Transport Aircraft Configuration for Sustained Hypersonic Flight
## 4 CFD Analysis of Ramjet Nozzles
### Dual Bell Nozzle  
Figure 24 depicts the performance of the dual bell nozzle at the nozzle design point. As mentioned earlier, the base nozzle suffers an oblique internal shock owing to the sharp turn in the flow as the fluid exits the nozzle throat in the nozzle. The rapid pressure drop as can be seen in the exit of the base nozzle, and the extended nozzle along the flow axis allows for acceleration along the jet axis throughout the nozzle boundaries along the kernel zone.  
The most noticeable feature of the dual bell CFD contours would be the formation of shock diamonds within the nozzle boundaries. Past the point of inflection, the flow is attached to the wall until the exit plane, where the full geometrical area ratio is utilised as discussed in Section 3.3.3.  
Additionally, in the dual bell nozzle, the radial gradient region is significantly smaller with a higher overall velocity achieved throughout compared to the bell nozzle. Smaller radial gradients lead to a lower chance of separation at different altitudes, as discussed in Section 3.3. The higher velocities in the near wall region lead to the flow being less affected by the adverse pressure gradient of the outside boundary pressures. Hence, weaker shocks produced at the inflection point and the lip of the nozzle lead to efficient expansion of the exhaust throughout and beyond the nozzle. This results in a higher exit velocity, leading to considerable gain in the momentum thrust achieved by the nozzle.  
The expansion fan at the lip of the nozzle exit causes the flow to expand outwards, accelerating it away from the jet axis. Compared to the other two nozzles types, the shear layer is much tamer and the jet being produced generates a much more efficient velocity and therefore a better axial thrust. At a ramjet operational altitude of 50,000 ft, the nozzle generated a gross thrust of 1.89 \(\times\) 10\({}^{6}\) N.  
Figure 25 shows the pressure vs Mach plots along the axial length of this nozzle up to and beyond the nozzle throat (where the pressure drops drastically). As presented, the expansion process continues until the nozzle exit, at position 4.3 m, where the shock induced by the nozzle lip causes the pressure to rise and the fluid interaction with the expansion fan decreases the velocity again. This leads to the formation of shock diamonds, discussed in Sections 3.2.1 and 3.2.2, that are dissipated due to the energy cascade between the two boundary flows over a course of the axial length, leading to the exhaust plume pattern.  
Figure 24: (**Top**) Pressure contour and (**Bottom**) Mach contour dual bell nozzle thrust = 1.89 \(\times\) 10\({}^{6}\) N, \(NPR\approx\) 76.5, H1 = 2.55, V1 = 1.65, V2 = 0.85, R1 = 7, R2 = 1.
## 5 Proposed Protocol to Secure E-Commerce Transactions
### Employing Secret-Key and Public-Key Encryptions
#### 5.1.1 ElGamal  
In our protocol, we implement an asymmetric algorithm that involves two keys: a public key and a private key. These keys are utilized to generate large and random keys, enhancing the security of e-commerce transactions. We choose the ELG algorithm due to its high efficiency in generating random keys of various lengths and sizes, such as 768, 1024, 2048, 3072, 4096, 7680, and 15,360 bits. In our proposed protocol, we use a key size of 1024 bits. To generate the secret key, we divide the key obtained from the EIG algorithm using the XOR process, resulting in a secret key size of 256 bits. This secret key is employed for encryption and decryption operations using the FER algorithm. The EIG algorithm is also used to generate the public and private keys. The key generation process is as follows:  
* Select a large prime number at random \(q\);
* Select a random number \(g\), which referred a random multiplicative to as a generator component;
* Select a third number at random \(K_{r}\) from \(1\ldots q-1\) as the private key;
* Calculate \(y\) by using the formula: \(y=gK_{r}\ mod\ q\) as the public key;
* \(K_{r}\) should be kept secret as a private key, \(q\), \(g\) and \(y\) are published as public key (\(K_{u}\)).  
We use data leakage detection technology during the process of creating the keys. Next, we divide the \(K_{u}\) into four sub-keys, and with the addition of the merchant ID number for each sub-key and the XOR operation for each sub-key, we derive the public key encryption and decryption using FER. Figure 3 illustrates the methodology of the system.  
Figure 3: Diagram of protocol methodology.
# How Biological and Environmental Factors Affect the Quality of Lavender Essential Oils
## 1 Introduction  
The _Lavandula_ genus consists of a diverse cluster of small perennial herbaceous plants or shrubs that vary in morphological, habitat, and chemical composition. It is well known for its aromatic leaves and flowers [1]. These plants include 39 highly hybridised species and approximately 400 registered cultivars [2, 3]. Lavender is grown worldwide, indicating its ability to adapt to different climates [4]. Lavender essential oil (EO) primarily comprises mono- and sesquiterpenoids, predominantly stored in the peltate glandular trichome (PGT) [5, 6]. _Lavandula angustifolia_ and the hybrid between _L. angustifolia_ and _Lavandula latifolia_, known as _Lavandula x intermedia_ (commercially reported as lavandin), are cultivated principally for the distinctive characteristics of their essential oils, used mainly in the perfume and cosmetic industry and aromatherapy [7, 8, 9].  
Furthermore, the essential oils of _Lavandula_ species are valuable and have tremendous commercial value in the pharmaceutical, food and flavour industries [10]. The pleasant aroma of lavender depends on the various monoterenes synthesised, and these accumulate primarily in flowers [11]. The most valuable lavender oil characteristic in the perfume and cosmetic industries include the increased amounts of linalyl acetate andlinalool. Meanwhile, lavender oil, more rich in camphor amounts, is exclusively used in aromotherapy [12].  
Lavender EO demonstrates sedative, anxiolytic, analgesic, anticonvulsant, and anaesthetic activity in the central nervous system. It also exhibits antioxidant, antimicrobial, anti-inflammatory, spasmolytic, and carminative properties [13]. Spike lavelender EO, by tradition, is used for its antibacterial, carminative, antifungal, anti-depressive, and anti-inflammatory activities. It is also effective for burn injuries and wounding. Moreover, it is also utilised as a component in perfumes and fragrances, as well as being used as a flavouring agent [14].  
Lavandula essential oil is produced annually in an amount of about 1500 tons [15]. Bulgaria and France are the leading lavender production countries, followed by countries in Europe, Asia, Australia, Africa, and the USA [16].  
This manuscript examines the biological and environmental factors affecting the production and quality of lavender EO, particularly highlighting studies from the last twenty years. Specifically, this review describes how environmental, geographical, diurnal, plant characteristics and developmental factors contribute to the production and quality of lavender EO. Furthermore, factors affecting the biosynthesis of lavender terpen at transcriptional levels are analysed.
###### Abstract
On the other hand, as wireless communication systems explore dual-band, CP DRAs have gotten a lot of interest [27, 28]. An external quadrature coupler degenerates the fundamental HEM111 and higher-order HEM113 modes in a dual-fed dual-band Circularly polarized DRA. AR bandwidths of 12.4 percent for the lower bands and 7.4 percent for the higher bands are achieved with this design [29]. This model, however, necessitates a sophisticated feeding network, which considerably increases the size. A single-fed dual-band Circularly polarized chamfered DRA was published in parallel [30]. The AR bandwidths are comparatively narrow, with just 5.2% and 1.4% for the bottom and upper bands, respectively, despite the model's modest feeding network. In contrast to the DRA in [31], which uses a diagonal groove on the top face of the DRA to increase AR bandwidth [32], the DRA in [32] uses a design with a diagonal groove on the top face of the DRA to increase AR bandwidth. Unfortunately, the increase in AR bandwidth is not significant, with only 6.3% and 6.8% for the lower and upper bands, respectively. A customized circular patch on top of CP DRA is investigated in [33]. It has relatively narrow 3-dB AR bandwidths of 3.16% and 5.06%. Mostly, single-fed structures are chosen for the merits of high aperture efficiency, reduced loss, and compact size. Orthogonal circularly polarized waves with anticipated phase differences can be attained by multi-resonant modes of the radiator rather than the feeding network [34]. Indeed, it is challenging to design dual-band dual-CP antennas. In this research article, a single-fed dual-band circularly polarized DRA is proposed for GPS and WLAN communications. In section II, initially, a Linear polarized DRA is excited through a single conformal metal strip, and then circularly polarized radiation is achieved by cross shape feed structure. To generate dual-band performance, RDRA is excited in its fundamental quasi-TE111 mode and higher-order quasi-TE113 mode based on the cross-shaped feed. The cross-shape conformal metal feed achieves Orthogonal Circularly polarized wave characteristics. The metal strip on top of RDRA gives the antenna more gain and a wider AR bandwidth (ARBW), ensuring reliable GPS/WLAN communications and overcoming the disadvantages of single-fed antennas' limited ARBWs. In addition, in section II, a design guideline was introduced to further clarify the process (1-5). Section III also includes a description of the antenna fabrication process as well as measurement findings. The suggested design has 6.4% and 25.26% impedance bandwidths, respectively, with 3-dB AR bandwidths of 21.26% (lower) and 27.82% (upper), as well as 7.7 and 5.9 dBi maximum gain. The proposed antenna's reflection coefficients, ARs, radiation patterns, and gains are investigated, with the reasonable agreement between measured and simulated findings.
# Conversion of Stearic Acid into Bio-Gasoline over Pd/ZSM-5 Catalysts with Enhanced Accessibility
## 4 Conclusions  
Palladium supported over either nanocrystalline or hierarchical ZSM-5 samples showed remarkable properties for liquid-phase conversion of stearic acid into liquid fuels using mild reaction temperatures under nitrogen atmosphere. These catalysts exhibited high selectivity towards gasoline-range hydrocarbons, plus an additional share of gaseous components produced by end-chain cracking reactions. The occurrence of Pd in the catalyst composition led towards an increase in the gasoline selectivity, due to the higher extent of the oligomerization/cyclization/aromatic pathway (OCA), which promoted the conversion of the light olefins, formed as primary end-chain cracking products.  
When using ZSM-5 supports with hierarchical porosity, both stearic acid conversion and gasoline selectivity were significantly improved. These facts were caused by the enhanced accessibility and better Pd dispersion attained over the hierarchical zeolites in respect to the Pd/n-ZSM-5 catalyst. It is also noteworthy that the increase of the Al content in the hierarchical Pd/h-ZSM-5 catalysts brought about a lower increase in conversion than the expected one, considering the rise of the zeolite acid site concentration. This fact was indicative of the critical role played by the Pd species in the activity of the catalysts, suggesting that the availability of the Pd centers may become a limiting factor in the conversion of stearic acid.  
The enhancement of the reaction temperature increased the stearic acid conversion, reaching virtually complete conversion at 325 \({}^{\circ}\)C. Interestingly, the selectivity towards gasoline underwent a high increase with this variable, from 46% at 275 \({}^{\circ}\)C to a superb value of 86% at 325 \({}^{\circ}\)C. This phenomenon was explained in terms of a larger extent of the OCA pathway.  
Accordingly, by adjusting the zeolitic support properties and operation conditions, it is possible to achieve Pd/ZSM-5 catalysts showing both high catalytic activity and selectivity for the conversion of fatty acids (stearic acid) into bio-gasoline.  
Conceptualization, D.P.S.; methodology, M.A. and L.B.; software, M.A. and L.B.; validation, J.M.E.; formal analysis, M.A. and L.B.; investigation, M.A.; resources, L.B.; data curation, M.A.; writing -original draft preparation, J.M.E.; writing-review and editing, D.P.S.; visualization, D.P.S.; supervision, D.P.S.; Project administration, D.P.S. and J.M.E. funding acquisition, D.P.S. and J.M.E.  
This research was funded by Ministry of Economics and Competitiveness of Spain, grant number CTQ2014-60209-R.  
The authors declare no conflict of interest.
## 5 Conclusions  
The structural characterization indicates that the incommensurate phase exhibits higher-order satellite reflections with two stability regions. The time-resolved results show that a complete phase transition in two stages is launched when the exciting light pulses exceed a fluence of 3.5 mJ/cm\({}^{2}\). An immediate reduction of the order parameter takes place at the surface. This newly created high symmetry phase then propagates into the material at a constant velocity. The velocity of the melting front could be determined to be 3.7 \(\pm\) 0.2 m/s through the depth-dependent disappearance of the order parameter. This observation of a slow melt front is suggestive of a first-order character to the laser-induced transition.  
[PERSON] and [PERSON] had the idea and designed the experiment. [PERSON] and [PERSON] provided the sample. [PERSON], [PERSON], [PERSON], [PERSON] and [PERSON] performed synchrotron measurements to characterize the static structure of the sample. [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON] and [PERSON] performed the experiment at SACLA with the help of [PERSON], [PERSON], [PERSON] and [PERSON], the local collaborators. [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], and [PERSON] performed two rounds of experiments at microXAS. [PERSON] analyzed the data with input from co-authors. [PERSON] performed the density functional theory calculations. [PERSON] and [PERSON] wrote the manuscript and all authors contributed to its final version.  
**Funding:** The research leading to these results has received funding from the Swiss National Science Foundation and its National Center of Competence in Research, Molecular Ultrafast Science and Technology (NCCR MUST), E.A. acknowledges support from the ETH Zurich Postdoctoral Fellowship Program and from the Marie Curie Actions for People COFUND Program. E.M.B. acknowledges funding from European Community's Seventh Framework Programme (FP7/2007-2013) under Grant Agreement No. 290605 (PSI-FELLOW/COFUND).  
**Acknowledgments:** We would like to thank [PERSON] and [PERSON] for technical support at the microXAS beamline and [PERSON] at the Material Science beamline at SLS. Time-resolved X-ray diffraction experiments were performed at SACLA with the approval of the Japan Synchrotron Radiation Research Institute and the Program Review Committee (JASRI Proposal No. 2016A8021, Ultrafast dynamics of a phonon-coupling driven phase transition in Sn\({}_{2}\)P\({}_{2}\)Se\({}_{6}\)).  
**Conflicts of Interest:** The authors declare no conflict of interest.
# Multi-Relational Graph Convolution Network for Service Recommendation in Mashup Development
## 3 Multi-Relational GCN Based Service Recommendation Model
### Overall Framework
#### 3.2.1. Graph Construction
We denote the description embedding matrix as \(D\in\mathbb{R}^{N\times NK}\) or \(D\in\mathbb{R}^{N\times ND}\), where each row represents the vector representation of the textual description of mashup or service learned from LDA or doc2 vec model. The cosine similarity is used to measure the similarity between vectors. We denote the weight matrix for the functional relation \(\mathcal{R}_{D}\) as \(W^{D}\in\mathbb{R}^{N\times N}\), and the functional similarity between any two nodes \(i\) and \(j\) is measured as \(W^{D}(i,j)=\frac{D_{i}\cdot D_{j}}{\|D_{i}\|\|D_{j}\|}\). In this case, each node is connected to all other nodes in the graph of relation type \(\mathcal{R}_{D}\) with weights equal to their functional similarity. However, modeling the functional relation as a complete graph is unfavorable as a mashup or service is generally only similar to a few mashups and services, as such, a large proportion of edges with small weights will introduce a lot of noise and increase the memory and computation costs. Therefore, we prune the graph where only \(\tau_{1}\) edges with the largest weights for each node are retained. In this way, each mashup/service is connected to at least \(\tau_{1}\) most similar mashups and services in terms of textual descriptions, and the edge weights are the degrees of similarity. The functional relation is represented as an adjacency matrix \(A^{D}\in\mathbb{R}^{N\times N}\), which only preserves the significant values of \(W^{D}\). * Tagging Relation. There is a tagging relation \(\mathcal{R}_{T}\) between the nodes if two nodes share at least one common tag. The tagging relation is represented as an adjacency matrix \(A^{T}\in\{0,1\}^{N\times N}\) with \(A^{T}(i,j)=1\) if nodes \(i\) and \(j\) have at least a common tag, i.e., \(T_{i}\cap T_{j}\
eq\emptyset\), and otherwise 0. As some popular tags are annotated by a lot of mashups and services, a service may possess a large number of tagging relations. To reduce the computational burden in the graph convolution, for each node, we randomly sample \(\tau_{2}\) nodes that share the same tag. In this case, the tagging relation can still be preserved as the graph convolution process can learn the indirect tagging relation between services. In the end, we construct graphs with three relations represented as three adjacency matrices \(A^{C}\), \(A^{D}\), and \(A^{T}\). Figure 1 shows an example of the graphs with three mashups and three services. Different relations are denoted by different edge colors, and the functional relation has associated weights. We can see that, while mashup \(m_{3}\) has no composition relation with other services, it has a rich interaction with other mashups and services in terms of functional and tagging relations. Note that other types of relations between nodes can be incorporated, such as services developed by the same company.