esa-sceva/satcom-chunk-collection huggingface dataset:
# Evaluation of Coupling PV and Air Conditioning vs. Solar Cooling Systems--Case Study from Jordan
## 2 Materials and Methods
### Site Description  
German Jordanian University is a public university situated in Amman, close to Madaba, Jordan, with a latitude of 31.77\({}^{\circ}\) and a longitude of 35.802\({}^{\circ}\). The climate of Amman is characterised as being inland with significant variations in air temperature experienced in different seasons. In the standard summer months from May to September, the maximum temperatures generally happen in July and August between the hours of 13:00 and 15:00, during which, the air temperature can be as high as 40 \({}^{\circ}\)C. The solar radiation typically peaks at approximately 1000 W/m\({}^{2}\) on optimally inclined planes in Amman at noon, as illustrated in Figure 1.  
The extant system of solar cooling and heating is positioned on the roof of Building C located on the GJU campus in Amman, Jordan, in which approximately 5000 students are enrolled. The absorption system that was examined for this study will complement the already installed traditional compression system in Building C. Building C's cooling capacity equates to 0.7 MW and the proportion of H2O-LiBr was intended to be approximately 10% of the overall cooling capacity. Building C comprises four storeys, as well as a basement, where the overall floor area is around 7500 m\({}^{2}\). The ground and third floors are primarily used as offices and laboratories, whereas the other floors include classrooms and offices for academic personnel.
## 6 Conclusions  
In this work we analyzed the throughput and the packet loss rate when multiple satellites cover a cluster of devices, in a direct-to-satellite IoT network. The uplink channel was modeled considering on-off fading, with potentially different erasure probabilities at each satellite. Then, we proposed an intelligent traffic load distribution algorithm, which assigns non-uniform traffic loads per position of the satellites within the constellation lap. Numerical results demonstrate that both the throughput and the packet loss rate vary considerably with the set of erasure probabilities, confirming the importance of the proposed mathematical analysis. Moreover, while also demonstrating the convenience of ITLD in terms of performance and algorithmic simplicity, the impact of the proposed non-uniform traffic load distribution was also assessed, where it became clear that in cases of high total channel load, the advantage of non-uniform distribution over the uniform one is quite large. In addition, we showed the positive impact of increasing the number of satellites within the constellation and the spacing between them.  
As future works, we intend to investigate the optimum overall throughput in the case of a constellation with different sets of erasure probabilities and satellite spacing. Moreover, we also intend to design a simple (low-complexity) traffic load allocation algorithm that may approach the performance of the proposed ITLD method or even the optimum overall throughput, while adhering to the low computational and memory capabilities of IoT devices and nanosatellites. Finally, another focus will be on the exploitation of inter satellite links for providing a high level of coordination and cooperation among the satellites.  
Conceptualization, S.M.-S., M.E.P., S.C. and R.D.S.; methodology, S.M.-S. and R.D.S.; formal analysis, S.M.-S. and R.D.S., software, F.A.T.; validation, S.M.-S., M.E.P., S.C. and R.D.S; investigation, F.A.T.; resources, F.A.T.; writing--original draft preparation, F.A.T.; writing--review and editing, S.M.-S., M.E.P., S.C. and R.D.S.; Visualization, F.A.T. and S.M.-S., supervision, S.M.-S. and R.D.S.; funding acquisition, S.M.-S., S.C. and R.D.S. All authors have read and agreed to the published version of the manuscript.  
This work has been supported in Brazil by CNPq, Print CAPES-UFSC \"Automation 4.0\"; RNP/MCTIC (Grant 01245.010604/2020-14) 6G Mobile Communications Systems; and Chile by FONDECYT Iniciacion number 11200659 and FONDECYT Regular number 1201893.  
The authors declare no conflict of interest.
## 4 Results
### Assessment of the Structural Model and the Hypotheses
#### 4.2.2 Hypothesis Testing  
This study computed path coefficients and \(p\)-values based on a sample of 304 participants. As illustrated in Table 6 and Figure 3, all hypotheses received support at a significant level of \(p\) < 0.001.  
This study supports Hypotheses 1 and 2, demonstrating that both immersion (IM) and presence (PR) significantly positively influence spatial cognition (SC), with the effect of presence being more pronounced. Hypothesis 3 is also supported, although the impact of immersion on presence is relatively weaker, suggesting that additional factors may need to  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Hypothesis/Path** & **Estimate** & **S.E.** & **C.R.** & **Results** \\ \hline H1: IM\(\rightarrow\)SC & 0.341 *** & 0.061 & 5.230 & Supported \\ H2: PR\(\rightarrow\)SC & 0.491 *** & 0.061 & 7.106 & Supported \\ H3: IM\(\rightarrow\)PR & 0.252 *** & 0.074 & 3.613 & Supported \\ H4: IE\(\rightarrow\)IM & 0.260 *** & 0.071 & 4.253 & Supported \\ H5: IE\(\rightarrow\)PR & 0.257 *** & 0.074 & 4.234 & Supported \\ H6: VG\(\rightarrow\)IM & 0.288 *** & 0.068 & 4.693 & Supported \\ H7: VG\(\rightarrow\)PR & 0.291 *** & 0.072 & 4.721 & Supported \\ H8: IC\(\rightarrow\)IM & 0.374 *** & 0.066 & 5.935 & Supported \\ H9: IC\(\rightarrow\)PR & 0.255 *** & 0.070 & 4.044 & Supported \\ \hline \hline \end{tabular}
\end{table}
Table 6: Standardized Structural Estimates and Hypothesis Tests. *** \(p\) < 0.001.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Fit Indices** & **Criteria for Evaluation** & **Results** & **Model Fit** \\ \hline Absolute Fit & & & & \\ \(\chi^{2}\)/df & 1–3 indicates a good fit, \(<\)5 acceptable & 1.316 & Good \\ GFI & \(\geq\)0.9 is good, \(\geq\)0.8 acceptable & 0.899 & Acceptable \\ AGFI & \(\geq\)0.9 is good, \(\geq\)0.8 acceptable & 0.882 & Acceptable \\ RMSEA & \(\leq\)0.05 is good, \(\leq\)0.08 acceptable & 0.032 & Good \\ Incremental Fit & & & & \\ NFI & \(\geq\)0.9 is good, \(\geq\)0.8 acceptable & 0.898 & Acceptable \\ RFI & \(\geq\)0.9 is good, \(\geq\)0.8 acceptable & 0.888 & Acceptable \\ CFI & \(\geq\)0.9 is good, \(\geq\)0.8 acceptable & 0.973 & Good \\ Parsimonious Fit & & & \\ PNFI & \(>\)0.5 & 0.818 & Good \\ PGFI & \(>\)0.5 & 0.766 & Good \\ \hline \hline \end{tabular} Note. \(\chi^{2}\)/df: Chi-Square/Degrees of Freedom; GFI: Goodness of Fit Index; AGFI: Adjusted Goodness of Fit Index; RMSEA: Root Mean Square Error of Approximation; NFI: Normed Fit Index; RFI: Relative Fit Index; CFI: Comparative Fit Index; PNFI: Parsimonious Normed Fit Index; PGFI: Parsimonious Goodness of Fit Index.  
\end{table}
Table 5: Model Fit Index.  
be considered. For the other hypotheses (H4, H5, H6, H7, H8, H9), the analysis indicates that information content, interactivity, and visual guidance all significantly affect both immersion and presence, highlighting their importance in enhancing the user experience. Specifically, information content has the most substantial influence on immersion, while visual guidance plays a critical role in enhancing presence.
###### Abstract  
The extraction, processing and transport of crude oil in the Niger Delta region of Nigeria has long been associated with collateral environmental damage to the largest mangrove ecosystem in Africa. Oil pollution is impacting not only one of the planet's most ecologically diverse regions but also the health, livelihoods, and social cohesion of the Delta region inhabitants. Quantifying and directly associating localised oil pollution events to specific petrochemical infrastructure is complicated by the difficulty of monitoring such vast and complex terrain, with documented concerns regarding the thoroughness and impartiality of reported oil pollution events. Earth Observation (EO) offers a means to deliver such a monitoring and assessment capability using Normalised Difference Vegetation Index (NDVI) measurements as a proxy for mangrove biomass health. However, the utility of EO can be impacted by persistent cloud cover in such regions. To overcome such challenges here, we present a workflow that leverages EO-derived high-resolution (10 m) synthetic aperture radar data from the Sentinel-1 satellite constellation combined with machine learning to conduct observations of the spatial land cover changes associated with oil pollution-induced mangrove mortality proximal to pipeline networks in a 9000 km\({}^{2}\) region of Rivers State located near Port Harcourt. Our analysis identified significant deforestation from 2016-2024, with an estimated mangrove mortality rate of 5644 hectares/year. Using our empirically derived Pipeline Impact Indicator (PII), we mapped the oil pipeline network to 1 km resolution, highlighting specific pipeline locations in need of immediate intervention and restoration, and identified several new pipeline sites showing evidence of significant oil spill damage that have yet to be formally reported. Our findings emphasise the critical need for the continuous and comprehensive monitoring of oil extractive regions using satellite remote sensing to support decision-making and policies to mitigate environmental and societal damage from pipeline oil spills, particularly in ecologically vulnerable regions such as the Niger Delta.  
remote sensing; Earth observation; machine learning; synthetic aperture radar; landcover; pollution; Niger Delta; mangroves
## 2 Materials and Methods
### Optimal Parameters Determination  
Using an experimental design by [PERSON] (3\({}^{3}\)), the three factors and the three levels were established for BK510 Lys and AgNP-BK510 Lys, as shown in Table 3. The response variable was the lytic activity, defined as:  
\[LA=\frac{\Delta OD_{600}}{\Big{(}t_{f}-t_{0}\Big{)}(E)}[=]\frac{OD_{600}}{(\text {s})(\text{mg})} \tag{1}\]  
where:  
\(LA=\text{lytic activity}\)\([=]\frac{OD_{600}}{(\text{s})(\text{mg})}\)  
\(\Delta OD_{600}=\text{Optical Density Difference at 600 nm}\)  
\(t_{f}=\text{Final time}\)\([=]\) seconds  
\(t_{0}=\text{Initial time}\)\([=]\) seconds  
\(E=\text{Enzyme}\) (BK510 Lys or AgNP-BK510 Lys) concentration \([=]\) mg.  
The BK510 Lys systems were prepared with 100 uL of the endolysin (Fagox-EL, pharmaceutical grade) solution (to obtain a mass of 0.14, 0.70, and 1.25 mg) and 900 uL aliquots of _S. aureus_ cell suspension, at an OD\({}_{600}\) between 0.400 and 0.500 in 1.5 mL microtubes (Axygen, Union City, CA, USA). The systems were incubated for 15 min and 5 h at 20, 30, and 40 \({}^{\circ}\)C, according to the experimental design; the OD\({}_{600}\) was measured at each time. The pH value was adjusted at 5, 7, and 9 according to the experimental design (using TRIS-HCl and TRIS-base, Sigma Aldrich). Each experiment was evaluated in duplicate.  
The AgNP-BK510 Lys (2:1 ratio) systems were prepared with 100 uL of the conjugates solution (to obtain a mass of 0.01, 0.07, and 0.13 mg) and 900 uL aliquots of _S. aureus_ cell suspension, at an OD\({}_{600}\) between 0.400 and 0.500 in 1.5 mL microtubes. The systems were incubated for 15 min and 5 h at 20, 30, and 40 \({}^{\circ}\)C; according to the experimental design, the OD\({}_{600}\) was measured at each time. The pH values were adjusted at 5, 7, and 9, according to the experimental design, using TRIS-HCl and TRIS-base. Each experiment was evaluated in duplicate.  
The positive control was prepared using 5 uL of ciprofloxacin (Sigma Aldrich, 17850-5G-F) at 5 mg/mL and 955 uL aliquots of _S. aureus_ cell suspension. The negative control was prepared using 5 uL of Phosphate Buffer (Meyer, reactive grade) and 955 uL aliquots of _S. aureus_ cell suspension.  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**System**} & \multicolumn{3}{c}{**BK510 Lys**} & \multicolumn{3}{c}{**AgNP-BK510 Lys**} \\ \cline{2-7}  & **Temperature** & **pH** & **BK510 Lys** & **Temperature** & **pH** & **AgNP-BK510 Lys** \\  & **(\({}^{\circ}\)C)** & **pH** & **(mg/mL)** & **(\({}^{\circ}\)C)** & **(mg/mL)** \\ \hline
1 & 20 & 5 & 0.70 & 20 & 5 & 0.07 \\
2 & 40 & 5 & 0.70 & 40 & 5 & 0.07 \\
3 & 20 & 9 & 0.70 & 20 & 9 & 0.07 \\
4 & 40 & 9 & 0.
# Retrofitting of Steel Structures with CFRP: Literature Review and Research Needs
## 2 Bond Behavior between CFRP and Steel  
The bond between CFRP and steel plays a major role in the performance of steel components retrofitted with CFRP. The role of the adhesive layer is to carry the tensile forces of the steel substrates and transfer them to the CFRP composites. A comparison between the CFRP/steel and CFRP/concrete bonded interfaces reveals the main contrast in terms of the bond behavior. Indeed, adhesives in the CFRP/steel joints are regarded as the weakest link, whereas the bond behavior of the CFRP/concrete shows that concrete acts as the weakest link [34]. Therefore, to achieve the maximum capacity of the CFRP retrofitting system that follows up with the CFRP rupture, the selection of the most effective adhesives is crucial [35]. Furthermore, many other parameters have been found influential on the bond behavior of the retrofitted elements. These parameters include the CFRP elastic modulus, CFRP bond length, CFRP configuration, adhesive type, adhesive thickness, anchorage system, and surface preparation of the steel substrate. It should be noted that temperature is also considered as one of these influential parameters. There are some comprehensive literature reviews that focus on the thermal and environmental effects [36; 37].
## 1 Introduction  
In the seismic design and evaluation of reinforced concrete bridge columns, it is vital to have a method for determining the shear strength to avoid shear failures. Such a method should be capable of accounting for the key parameters affecting the shear strength.  
The 2020 AASHTO LRFD Specifications [1] for designing bridge columns for shear strength under seismic actions are investigated using available test results of columns that failed in shear. The columns investigated were tested under reversed-cyclic loading and had a variety of axial load levels, amounts of shear and longitudinal reinforcement, cross-sectional shapes, aspect ratios, and material properties. Suggestions are made to improve the seismic strength predictions using the AASHTO Simplified and General Procedures for shear design.  
While the AASHTO design provisions for new bridges provide excellent seismic performance, with adequate shear reinforcement and confinement reinforcement, care needs to be taken in evaluating existing bridge columns in older structures. To evaluate the performance of an older bridge, it may be necessary to carry out nonlinear dynamic analyses. To carry out such analyses, the complete hysteretic responses of the columns need to be modelled. To investigate the full seismic performance, nonlinear finite element analysis predictions are compared with the results of columns tested under reversed-cyclic loading and having different failure modes and levels of ductility. These analyses demonstrate the ability to predict the response of columns with ductile (flexural yielding), moderately ductile (flexure-shear), and brittle (shear) failure modes. This more detailed nonlinear finite element analysis provides the engineer with a means of assessing the expected seismic performance of existing bridge columns.
## 4 Conclusions  
Small-hole components of Inconel 718 are widely used in aerospace engineering, medical devices, and other fields. Limited by the material properties of Inconel 718, the machining efficiency of small holes seriously restricts its wide application. Thus, hydrogen embrittlement-enhanced ultrasonic machining, HEUM, was proposed for the efficient machining of a small hole on Inconel 718. The conclusions are as follows:  
1. HEUM significantly enhanced both machining efficiency and the surface roughness of the hole sidewalls. However, there was no notable change in surface roughness as the ultrasonic amplitude and HE voltage increased.
2. Under the experimental conditions, the specific material removal rate improved by 27.4% compared to conventional ultrasonic machining when subjected to 5 V HE for 10 min. This improvement is attributed to the substantial reduction in the plasticity of Inconel 718 after 10 min, which was beneficial for high-efficiency material removal.
3. Following the machining of blind holes, surface roughness at the bottom of the holes decreased as the HE time increased. Notably, the area exhibiting brittle fractures at the hole's bottom expanded with longer HE durations. This change occurs because the mechanism of material removal shifts from plastic deformation to brittle fracture, resulting in a significant enhancement in surface finish quality.
4. The optimal processing parameters were determined to be an ultrasonic amplitude of 2.28 \(\upmu\)m, an HE voltage of 5 V, and an HE time of 10 min. Under these conditions, a 1 mm through-hole with a surface roughness (Ra) of 0.318 \(\upmu\)m can be achieved through HEUM. Therefore, it is obvious that HEUM is a promising method for small-hole machining on hard-to-difficult machining material.  
Conceptualization, S.L.; methodology, S.W. and J.Q.; formal analysis, S.L. and S.W.; investigation, S.L. and J.Q.; data curation, S.W.; writing--original draft preparation, S.L. and M.F.; writing--review and editing, S.L. and M.F.; visualization, J.Q.; supervision, S.L.; project administration, S.L.; funding acquisition, S.L. All authors have read and agreed to the published version of the manuscript.  
This work was funded by the National Natural Science Foundation of China (52105479) and major scientific and technological innovation projects of Wenzhou City (CN) (grant no. ZG2022029).  
Not applicable.  
Data Availability Statement: Data are all contained within the article. All data are fully available without restriction.  
Author [PERSON] was employed by the company Shenzhen KiSONICS Technology Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
## 2 Related Works
### Computing Network and Computing Resource Scheduling
Although these methods analyzed and optimized resource scheduling in the Computing Network from an implementation perspective, and the latter balanced the load of resource nodes, there remained an issue of lacking scheduling flexibility. In terms of centralized scheduling, the authors in [33] elaborated on the concept of Segment Identifier as a Service (SIDaaS) based on SRv6 and proposed the Programmable Service System (PSS) based on SIDaaS, providing a vital implementation method for integrated scheduling of computing and network resources. The authors in [34] proposed a lightweight, multi-cluster hierarchical edge resource scheduling solution based on a hybrid architecture of Kubernetes and K3s. This scheme achieved unified management and scheduling of a large number of edge computing resource nodes. The authors in [35] implemented coordinated scheduling of computing and network resources using SDN technologies, orchestrating computing and services on the underlay network. However, with the increase in the number of ubiquitous computing resource nodes and diversified user demands, the aforementioned centralized scheduling methods faced issues of scalability and reliability limitations, which similarly had an adverse impact on resource scheduling. Furthermore, some computing resource scheduling mechanisms outside of Computing Network have utilized multi-criteria decision-making approaches to aid in the allocation and scheduling of computing resources, which is also of reference value to this paper. For instance, the authors in [36] employed the Analytic Hierarchy Process (AHP) within Kubernetes for resource scaling decisions, optimizing the allocation of computing resources. The authors in [37] used the TOPSIS method for placing Virtual Network Functions (VNFs) within computing resource clusters to complete resource invocation, significantly enhancing the satisfaction rate of requests. In [38], the authors introduced a two-phased Multi-Attribute Decision Making (MADM) method, utilizing the P2P formalism to discover and allocate computing resources. Overall, due to scalability limitations associated with centralized computing resource scheduling, distributed approaches have gained more widespread application. However, the aforementioned distributed resource scheduling mechanisms still face challenges, such as a lack of flexibility and awareness of user preferences. Computing resource scheduling based on ICN has the potential to address and improve these issues. Consequently, this paper proposes a computing resource scheduling architecture based on ICN, which has advantages in terms of scheduling flexibility and meeting diverse user preferences. A detailed analysis will be further elaborated on in the following sections.
# Model Mediation to Overcome Light Limitations--Toward a Secure Tactile Internet System
## 5 Security Issues  
Security represents an important issue for the tactile Internet applications and also haptic-based bilateral teleoperation systems, this because of the diversity of applications with the delay, availability, and reliability constraints [89].  
In the existing communication systems, the security is ensured via classical encryption techniques and other security algorithms that are implemented separately from the transmission [90; 91]. Current security algorithms are implemented at the higher layers of the communication protocol, which adds more delay to the end-to-end latency. Thus, traditional security and encryption methods cannot be used for the tactile Internet applications. Instead, security algorithms for the tactile Internet must be fed to the physical transmission and should be implemented with low computational complexity so as to work against attackers and eavesdroppers with ensuring very low end-to-end latency as required. New coding techniques and security algorithms will be developed for tactile Internet applications so that only legitimated receivers can decode the secured messages even with finite computational power [27].  
The maximum transmission rates of secure data, with the absolute rate of generation of secure keys represent main performance metrics of recent communication systems and as well, will be tactile Internet. This gives the priority to the technical security of transmission than classical coding, while designing the tactile Internet [17]. Dedicated hardware can be used for implementing such kind of coding and security methods with the transmission, these devises are such as the biometric fingerprints [27]. Furthermore, tactile Internet raises another security issue, which is user identification.  
The introduction of mediated systems to support the tactile Internet system will also help in solving security issues; since it breaks through the delay constraints and even if the traditional coding scheme is used it will be proper for a part of applications.