esa-sceva/satcom-chunk-collection huggingface dataset:
## 3 Data-Based Framework for Analyzing Sleep Data  
A data-based framework has been developed to assist clinicians in making more accurate diagnoses of patients' health status. With a growing number of individualsdiagnosed with OSA, PSG remains a key diagnostic method. This overnight test gathers a range of physiological signals, such as brain activity, SpO2 levels, heart rate, respiratory metrics, and eye and limb movement, depending on the equipment used. In this study, the Philips Alice 6 LDx PSG device was utilized [25]. Such comprehensive data are essential in determining the severity of OSA in each patient.  
Alongside PSG, patients complete the standardized STOP questionnaire, which provides additional context for assessing their condition. This combined approach captures a detailed view of each patient's sleep patterns and potential abnormalities, making it invaluable for identifying various sleep disorders. For each patient during sleep, two additional files are recorded. The csv_event file logs various types of events that occur throughout the night. Each event entry includes the associated sleep stage, timestamp, epoch number, body position, and event validity. The csv_hypnogram file records epoch numbers, the start time of each epoch, and the corresponding sleep stage.  
Applying machine learning and sophisticated statistical analysis to these data enables a more nuanced understanding of each patient's health profile by uncovering patterns that may not be easily observed otherwise. This allows for tailored treatments, better resource allocation, improved diagnostic accuracy, and the ability to track patient-specific trends.  
The platform developed here consolidates this data-driven approach by incorporating PSG data, stored in.edf files with additional patient-specific files containing sleep data and STOP questionnaire responses. Central to this platform is a suite of Python-based analyses that generate individualized health insights, integrating both statistical evaluation and machine learning for more dynamic data processing. The data and code are stored in Google Sheets and accessible via Node:js requests, while the web application's React.js front-end retrieves and visualizes patient data by referencing their unique patient ID.  
Figure 1 illustrates the overall system structure, and Figure 2 displays the application's user interface, which allows for visualization upon input of a patient ID. This comprehensive data framework offers a transformative approach in sleep medicine, making diagnostics more efficient, precise, and tailored to individual needs.  
Figure 1: System architecture: from data collection by recording patients to visualization through a web application, which provides doctors with a more interactive approach to analyzing the collected data.
# Bionic Design of the Vertical Bracket of Wide Angle Auroral Imager by Additive Manufacturing
## 4 Mechanical Analysis  
To verify the validity of the optimized design, finite element modeling of the original design and the bionic optimization design have been completed as shown in Figure 6. MSC/patran is used to model the vertical bracket, ignoring or simplifying some subtle features that have little influence on the deformation and stress distribution of the whole structure. In order to ensure the calculation accuracy, the mesh size of 5 mm is selected for modeling. The original design and the bionic optimization design are modeled as solid units.  
The selection of aerospace materials is crucial in aerospace component and system design cycles. The most common aerospace materials are aluminum alloy, carbon fiber, and titanium alloy. Due to the high specific strength, corrosion resistance, low temperature resistance, and good thermal conductivity, titanium alloy is used to manufacture the vertical bracket.  
The 12 screw holes of the vertical bracket connected to the satellite plane are fully constrained. Modal analysis is performed on the finite element model for the empirical design model and optimal design model. The eigenfrequencies in the three directions are shown in Table 3. Its first three natural frequencies and vibration modes for the vertical bracket are presented in Figure 7. It can be seen that the first three natural frequencies of the original structure are closely approximate to the bionic optimized structure. But the mass of bionic optimized structure is far less than the original structure, mass ratio reaches 23%.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Design** & **Original Design** & **Final Design** \\ \hline Mass (kg) & 11.2 & 8.6 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Comparison of original and optimized designs.  
Figure 6: Finite element modeling of the vertical bracket. (**a**) The original model. (**b**) The bionic optimization model.
# Clinical Applications of In Vivo and Ex Vivo Confocal Microscopy
## 2 In Vivo Confocal Laser Scanning Microscopy
### Main In Vivo CLSM Diagnostic Clues in Skin Cancers
Furthermore, different features can be observed in BCC depending on the degree of pigmentation. Pigmented BCC may show dendritic cells, corresponding to melanocytes inside the tumor island [48; 49], while non-pigmented BCC is characterized by dark silhouettes, defined as areas with hypereflectivity, corresponding to basaloid islands, outlined by bright collagen bundles in the surrounding dermis [48; 50]. The \"epidermal shadowing\" corresponds to large dark featureless areas creating a disruption of the epidermis in relation to clefting of the underlying tumor nests [46]. Additionally, RCM contributes to the recognition of criteria corresponding to different BCC subtypes [51], with an impact on treatment choice. Figure 2: **(a)** Dermoscopy of a melanoma in situ. **(b)** In vivo reflectance confocal microscopy showing several pagetoid cells (yellow stars) at the epidermal level and atypical cells at dermo-epidermal junction (yellow arrows). Scale bar 200 \(\upmu\)m. **(c)** Dermoscopy of a melanoma, 5.3 mm Breslow thickness. **(d)** In vivo reflectance confocal microscopy showing atypical melanocytes (white arrows), predominantly organized in nests and cerebriform nests (white star). Scale bar 200 \(\upmu\)m.  
AK/SCC are typified by disarranged or mildly atypical honeycomb pattern, with RCM [1]. Furthermore, in AK, nuclear retention, corresponding to parakaratosis in histology, is visualized as a dark round structure located in the middle of corneocytes. At the superficial dermis bundles of lace-like collagen can be observed [52]. Interestingly, RCM enables AK grading, depending on the amount of keratinocyte atypia, showing good interobserver correlation between RCM and histopathology, with consequent advantages in the choice of the best treatment and to monitor the response to AK therapy [53; 54; 55]. An increased keratinocyte atypia and architectural disorder are observed in SCC, as compared to AK. With RCM, Bowen disease, or in situ SCC, it shows atypical honeycomb pattern, disruption of the stratum corneum, S-shaped blood vessels, and targetoid cells while invasive SCC is characterized by dark areas with sharp and irregular contours, filled with amorphous material, corresponding to ulceration, architectural disarrangement, round or polygonal cells with speckled appearance and dark nucleus in epidermis and irregular dilated vessels [56; 57; 58]. Currently, in doubtful cases, the differential diagnosis between AK and SCC requires a skin biopsy. Figure 3: (**a**) Dermoscopy of a nodular basal cell carcinoma. (**b**) In vivo reflectance confocal microscopy showing tumor islands with palisading (blue arrows) and peripheral clefting in horizontal section. Scale bar 200 μm. (**c**) High-resolution fluorescence confocal microscopy image showing basaloid islands (blue arrows) with peripheral palisading and clefting that corresponded to the ones seen on hematoxylin & eosin digitally stained (**d**). Scale bar 200 μm.
## 3 Verification by a Two-Dimensional Finite Element Model  
### Finite Element Modeling  
A two-dimensional finite element model illustrated in Figure 3 is used to verify the correctness of the previous theoretical derivation. The arch height (\(H\)) ratio to length (\(L\)) is 1:4, the span is 50 m, and the arch height is 12.5 m. The cross-section of the arch rib and the tie-beam is a 2000 mm \(\times\) 2000 mm square tube with a wall thickness of 40 mm. The hanger adopts a circular section with a diameter of 120 mm, and the bridge deck is subjected to a uniformly distributed load of 9.8 KN/m.
# Dynamic Instability Analysis of a Double-Blade Centrifugal Pump
###### Abstract  
The flow instability of a double-blade centrifugal pump is more serious due to its special design feature with two blades and large flow passages. The dynamic instabilities and pressure pulsations can affect the pump performance and operating lifetime. In the present study, a numerical investigation of unsteady flow and time variation of pressure within a complete double-blade centrifugal pump was carried out. The time domain and frequency domain of pressure pulsations were extracted at 16 monitoring locations covering the important regions to analyze the internal flow instabilities of the pump model. The frequency spectra of pressure pulsations were decomposed into Strouhal number dependent functions. This led to the conclusion that the blade passing frequency (BPF) related vibrations are exclusively flow-induced. Large vortices were observed in the flow passages of the pump at low flow rate. It is noted that high vorticity magnitude occurred in the vicinities of the blade trailing edge and tongue of the volute, due to the rotor-stator interaction between impeller and volute.  
flow instability; double-blade centrifugal pump; pressure pulsation; vibration; computational fluid dynamics (CFD) +
Footnote †: journal: Applied Sciences
## 2 Materials and Methods  
### PM\({}_{2.5}\) Real-Time Monitors  
A laser-based light-scattering PM\({}_{2.5}\) sensor monitor (ESCORTAIR, ESCORT, Seoul, Korea) (weight \(<\)300 g, volume \(<\)510 cm\({}^{3}\)) consisted of an optical particle counting (OPC) PM sensor (INNOSIPLE1), CO\({}_{2}\) sensor, temperature relative humidity sensor, data transfer networking module and light-emitting diode (LED) display screen (Figure 1). In the ESCORTAIR, the sensing volume is illuminated with a laser and airborne particles are counted and processed one at a time. There were various IRMs commercially available in South Korea. In this study, however, we chose ESCORTAIR as they allowed us to directly transfer data to our data server using its Wi-Fi function.  
For comparison purposes, another inexpensive photometer type of PM monitor (PA, PurpleAir, Draper, UT, USA) ([[https://www.purpleair.com/](https://www.purpleair.com/)]([https://www.purpleair.com/](https://www.purpleair.com/))), mounting two Plantower sensors in a monitor, was used. PA is recommended its usage by AQ-SPEC (Air quality sensor performance evaluation center, South Coast Air Quality Management District, CA, USA) or US EPA (Environmental Protection Agency, NC, USA) as an IRM. The inlet system of these IRMs did not have an impactor or a cyclone unlike that of the RGM.  
The performance of the two IRMs (one OPC, that is, ESCORTAIR and one photometer, that is, PA) costed less than $300 were simultaneously compared with those of high-cost devices ($10,000 or so),that is, research-grade laser photometers including PDR-1500 (Thermo Scientific, Waltham, MA, USA) and SIDEPAK AM510 (TSI, Inc., Shoreview, MN, USA).  
These research-grade monitors have a cyclone inlet or an impact inlet for the measurement of the respirable fraction of airborne particulate matters in different environments and can provide real-time data. The SIDEPAK is a portable battery-operated personal aerosol monitor with an impact inlet and light-scattering laser photometer that provides real-time aerosol mass concentration. The PDR-1500 (Personal DataRAM 1500) is a nephelometric monitor with a cyclone inlet for the measurement of the respirable fraction of the airborne particulate matters. The PDR-1500 can simultaneously collect particles on a 37 mm filter for the gravimetric analysis by passing through the sensing zone.  
Figure 1: Layout of ESCORTAIR installed INNOSOPLE-1 PM sensor for measuring particulate matter (PM) concentrations.
# A Deep-Learning Approach for Identifying a Drunk Person Using Gait Recognition
## 3 Results  
### Gait Parameter  
Stride time, stride length, and stride velocity were selected as parameters for drunk gait, which is distinct from sober gait. These are the parameters that are mainly used in studies related to vision-based abnormal gait evaluation [9]. Walking time and stride length are, respectively, the time and distance taken for one gait cycle. One cycle of gait is from the point when one foot touches the ground to the point when the same motion appears. A total of 10 sober walks and 10 drunk walks were recorded for each subject, and the average value of the measured stride time and stride length for each walk was used as a parameter. The stride velocity was calculated by dividing the stride length by the walking time. As a result of analyzing the parameters extracted from the walking test videos of 20 subjects, we found that there was a significant difference between drunk and sober gait in terms of stride time, stride length, and velocity.  
In the drunk gait, the stride time was longer, the stride length was shorter, and the stride velocity was slower than in the sober gait. In addition, as can be seen in Figure 4, this difference was found in all 20 subjects. In the case of walking time, there was a difference of 1 to 8 frames based on a rate of 30 fps.  
Furthermore, to comprehensively compare the differences between sober and drunk gaits by parameters, we checked the (drunk/sober) values in Table 1. The drunk gait had a 13% longer stride time, a 13% shorter stride length, and a 22% slower stride velocity than the sober gait.  
These differences occurred because the Drunken Busters Goggles caused distortion of vision and decreased gait stability. Since such a decrease in gait stability appears after actual drinking, it is possible to identify a drunk individual by observing a gait that is slower and shorter than usual.  
Figure 3: Examples of Image Augmentation (IA) used to enlarge datasets.
## 2 Initiation of the Project  
### Contracts and Collaborators  
The most important part of a CubeSat project is the team. A cohesive team is necessary to achieve deadlines on time. This can include external collaboration with other institutions or enterprises that can complement their expertise areas. It is crucial that all stakeholders understand from the beginning how the rest of the team should be contributing to the project, their work pace, priorities, and limitations.  
In this sense, academic institutions and private companies have distinctive ways of working. On the one hand, companies should understand that people in the academia have to prioritize teaching and research tasks over the development of secondary projects. Moreover, the results of their work should conclude in publishable contents. On the other hand, industrial partners respond to economic incentives. They need to meet short-term milestones to satisfy the interests of investors, and they have a strong protective attitude regarding the intellectual property behind their products. These stimuli will sometimes drive the project to non-assumable workload or close to unethical compromises. Therefore, it is imperative to write a document formalizing the collaboration agreement with all stakeholders. This document should cover major possible conflict points, such as ownership, budgeting, responsibility sharing, decision making, information sharing and communication protocol between partners, publishable and confidential materials, image rights, media coverage, public representations, etc.  
In parallel, a realistic planning has to be made at the beginning of the project to prevent any misalignment in working speeds. If the relationship with external companies is strictly commercial, it is highly recommended to specify deadlines to their work and penalties if such work is not achieved on time. The launching phase has to be taken into account from the beginning. This is an important item in the budget, which also has consequences in the project schedule. Currently, there are only four operative launch brokers available for CubeSat developers [29]. They offer their services at prices per launch that move around $100,000 per unit CubeSat as a piggyback payload. Some more dedicated alternatives seem to be ready in the following years. In any case, the risk of failure is always assumed by the CubeSat developer. In general, any modification performed by the broker or any changes in the definition of interface without the explicit consent of the owner should not be acceptable. Hence, the interface design should be stated explicitly in the contract with the broker. Otherwise, the project may be blocked due to the late discussions concerning the permitted modifications for launcher integration.
# Algebraic Point Projection for Immersed Boundary Analysis on Low Degree NURBS Curves and Surfaces
## 3 Background on Algebraic Level Sets
### Normalization and Composition of Algebraic Level Sets  
The aforementioned procedure generates a monotonic and continuous distance measure for a basic parametric curve such as a Bezier curve. Piecewise polynomial curves such as NURBS curves, on the other hand, require decomposition to Bezier segments and composition of algebraic level sets of the obtained segments. Further, normalization for individual level sets is desired to yield a monotonically varying composed field. Considering a physical footpoint \(\mathbf{x}_{f}\), one can approximate \(\Gamma(\mathbf{x}_{f})\) to a first order using Taylor expansion:  
\[\Gamma(\mathbf{x}_{f})=\Gamma(\mathbf{x})-\frac{\partial\Gamma(\mathbf{x})}{ \partial\mathbf{n}}d \tag{13}\]  
Since the resultant has exact zero set on a parametric curve, i.e., \(\Gamma(\mathbf{x}_{f})=0\), one can derive a distance in the normal direction as follows:  
\[d=\frac{\Gamma(\mathbf{x})}{\frac{\partial\Gamma(\mathbf{x})}{\partial \mathbf{n}}}=\frac{\Gamma}{\|\
abla\Gamma\|} \tag{14}\]  
After obtaining normalized algebraic level sets for each decomposed Bezier segment, one can compose them using R-conjunction operation (Equation (10)) and thereby generate the desired algebraic level sets. As demonstrated in [23], the R-conjunction operation preserves the normalization of individual Bezier segments. However, an implicitized curve obtained from a Bezier curve of degree \(p\) may have as many as \(\frac{1}{2}(p-1)(p-2)\) self-intersections or double points [29]. Any double points inside the convex hull will affect the algebraic level sets construction, and therefore need to be moved out by sub-divisions of the Bezier curve. The algorithm to carryout this process is discussed in Reference [23]. Thus, for practical reasons of avoiding more than one double point while enabling sufficient generality in modeling complex geometries, the methodology is restricted to low degree NURBS curves \((p\leq 3)\). Figure 6 shows an example of algebraic level sets of an open curve containing two points with \(\mathcal{G}^{0}\) continuity.  
Figure 5: The control points of a cubic Bézier curve \(\mathbf{C}(u)\) form a convex hull consisting of four hyper-planes \(h_{1},h_{2},h_{3}\) and \(h_{4}\) with inner normals \(\mathbf{n}_{1},\mathbf{n}_{2},\mathbf{n}_{3}\), and \(\mathbf{n}_{4}\), respectively. Boolean intersection of the four hyper-planes using R-functions yields a trimming region \(\phi\geq 0\).
# The Role of Low Temperature Waste Heat Recovery in Achieving 2050 Goals: A Policy Positioning Paper
## 3 Results
### Heat Market Overview
#### United Kingdom  
A key initiative in England and Wales is the Heat Network Delivery Unit (HNDU), which was formed within the Department for Energy and Climate Change (DECC) in summer 2013 to help meet 2050 targets [27]. The Carbon Reduction Commitment (CRC) is a mandatory scheme that aims to improve energy efficiency and reduce CO\({}_{2}\). Eligible organisations must buy allowances to cover their reported emissions; hence, green DH investments have benefited from the scheme. Another mechanism with which to meet the 2050 goal is national and regional planning for infrastructure. The plans set the policy framework for infrastructure decisions (including heating infrastructure) through Planning Policy Statements (PPS). District heating plays a part in this scheme. These statements are combined with the Climate Change Levy (CCL) tax which taxes supplies of energy within the non-domestic sector including industry, commerce and the public sector. In the CCL, there are exemptions for fuel inputs and energy outputs from CHPs.  
An Enhanced Capital Allowances (ECA) scheme provides businesses with enhanced tax relief for investments in equipment that meet published energy-saving criteria. Eligibility for an ECA is a fiscal benefit available to new CHP schemes certified under the CHPQA programme. Since the most capital intensive element of distribution networks (the pipes) are not included, the scheme has limited overall effect in this sector. A number of funding programmes have been carried out in the UK. These include both grant capital support and assistance with pre-investment activities. One example is the Community Energy programme that aims to deliver new community heating schemes and refurbish old ones, thus reducing carbon emissions, alleviating fuel poverty and reducing frontline energy costs. Another similar scheme was provided through the Homes and Communities Agency [16].  
The government is progressing policy incentives that will reduce the heat demand of the existing building stock while promoting the uptake of renewable heating technologies. The recently deployed Green Deal is expected to remove the barrier of initial costs for energy efficiency improvements while the Renewable Heat Incentive (RHI) attempts to support market roll out of renewable heat technologies. However, the success of these policy initiatives is uncertain and the impacts on technology deployment are yet to be identified [28]. The need for district energy market regulation has been discussed but, to date, there is no regulation of the heat market [27]. Taking the interest of low temperature district heating investments into account, it is notable that no regulation explicitly supporting such investments exists in the UK [26].
# Closed-Form Performance Analysis of the Inverse Power Lomax Fading Channel Model
## 3 IPL Fading Channel Model Application  
The derived expressions for the PDF, CDF, and MGF provide a complete first-order statistical representation for assessing the performance of a wireless communication system operating under fading conditions. According to the general framework, communication link reliability is typically quantified in terms of the outage probability, while link quality is measured by the average error rate and ergodic capacity. The impact of fading is conventionally described by the amount of fading and the hyper-Rayleigh regimes.
## 4 Privacy and Security Enhanced Methods  
### Privacy-Preserving Arbitration Mechanism  
In cloud-edge collaboration ICSs, the arbitration mechanism is critical for ensuring both system security and data privacy. This section presents our novel privacy-preserving arbitration approach that protects sensitive edge outputs while maintaining effective system security.