esa-sceva/satcom-chunk-collection huggingface dataset:
# A Numerical Approach for the Efficient Concept Design of Laser-Based Hybrid Joints
## 2 Method and Models  
The approach is shown schematically in Figure 2. The detailed information on the individual steps is given in the following sections. The basis for the procedure is an FE model of the joining parts with an interlayer with a small thickness between the plastic and metal part. In dependence on the external forces applied to the joint, the values and orientations of the local stress tensors in the interlayer were determined. Based only on these stress tensors, load-optimized concepts for laser structuring were automatically developed with a numerical model (Section 2.1).  
The approach works by first eliminating low-stressed regions using a stress limit value. All the remaining regions were then grouped by a cluster algorithm while considering the specific manufacturing constraints of the joining technology. To each of these areas, different microstructures could then be assigned according to the specific stress states.  
For strength calculation, cohesive zone models (CZM) were set up, which locally consider the mechanical characteristics of the chosen microstructure for each area (Section 2.2). The required material parameters for the CZM were derived from FE representative-volume-element (RVE) models; so, in this case, it was a single cavity. Then, production costs were determined for the microstructure concepts by calculating a machine hour rate and laser production time (Section 2.3) based on the number, length, and distance of the cavities. Finally, the design, strength, and cost models were coupled in an optimization workflow to identify values for the design variables (e.g., stress limit, microstructure) that satisfy the cost and strength requirements.
## 3 Wiener-Granger Causality Analysis Theoretical Fundamentals  
The Wiener-Granger theory of causality is used in different areas of knowledge, for example, in neurology the WGC theory is used [39] to examine brain areas and the causal relationships between them. The WGC analysis was performed using sensors [40; 41], and also, in magnetic resonance images [42; 43], the WGC theory is being used for the study of causal relationships between areas of the brain that perform activities. Other fields of science where the WGC theory has been applied are video processing for massive identification of people and vehicles [44; 45; 46] and the analysis of complex scenarios [47]. In this proposal, for the first time, the WGC theory is applied for the recovery of natural elements and scenes.  
For the sake of brevity, the theory is presented only for two random processes, being extensible to \(n-\) processes, and to avoid extensive mathematical models. In our approach, a random process corresponds to a signal reading associated with a type of texture within a natural scene. Thus, for the presented analysis, each texture reading corresponds to a stochastic process represented by \(C_{i}\), \(i\) being the \(i\)-th texture that has a stochastic behavior within a scene.
# Gravity Field Recovery Using High-Precision, High-Low Inter-Satellite Links
## 1 Introduction
In the context of a Next Generation Gravity Field Mission (NGGM), various satellite constellations enabling a self-de-aliasing of high-frequency signals were investigated, such as the dual-tandem Bender-type mission [21], consisting of one near-polar pair and one inclined pair. Such a constellation allows the combination of two anisotropic measurements taken in different directions, which increases the isotropy of the combined system. A further concept is the pendulum formation where two satellites are on slightly shifted orbit planes in such a way that the line of sight between the satellites does not only contain along-track components, but also cross-track components [22]. Such innovative satellite constellations offer the application of improved gravity field processing methodologies in order to exploit the full potential of gravity field solutions with enhanced spatial and temporal resolution. [PERSON] et al. 2011 [23] proposed a method where low-resolution gravity field solutions are co-parameterized for short periods (e.g., daily) together with the long-term solutions (e.g., monthly) in order to mitigate the non-tidal high-frequency signals (especially atmosphere, ocean, and to some extent, also hydrology). A method to reduce tidal aliasing errors proposed by [PERSON] & Pail 2018 [24] aims at a co-parameterization of ocean tide parameters over time spans of several years, where the estimated tide model is used for de-aliasing during gravity field retrieval in a second processing step. In this paper we pick up the point of new satellite constellations using an innovative observation concept of high-precision high-low inter-satellite ranging, which was proposed as the (MOBILE) mission [25] in response to European Space Agency (ESA)'s Earth Explorer 10 call. The observation geometry and the measuring principle of this satellite constellation are based on the Geodesy and Time Reference in Space (GETRIS) [26] concept describing a global space-borne infrastructure for data transfer, clock synchronization, and ranging, where gravity field recovery can be one of the first beneficiary applications of such an advanced geodetic space infrastructure. In this study, we analyze the potential of the MOBILE mission qualitatively and quantitatively, and compare gravity field solutions with GRACE Follow-On-like solutions by means of full-scale numerical simulations. Furthermore, the potential of an extended processing method for the reduction of temporal aliasing is investigated for the MOBILE concept. In the following Section 2, the MOBILE observation configuration is described, while Section 3 gives an overview of the simulation environment includingobservation equations and stochastic modelling. In Section 4 the estimated gravity field solutions are analyzed and assessed. The main conclusions are summarized in Section 5, and in Section 6, a short outlook is given.
## 3 Quantum Channel Positioning  
As already mentioned, the quantum channel is very weak in terms of optical power. Typically, its power ranges between \(-80\) and \(-90\) dBm. Moreover, by the very nature of the transmission, it cannot be amplified or repeated (see the no-cloning theorem). Even in the case of dark fiber transmission, the maximum range of the QKD link is very limited. In practice, this is usually resolved by using so-called trusted repeaters, defined in ITU-T recommendation Y.3800. However, when additional channels are included, other malicious phenomena contribute to the degradation of the quantum channel. Among the most important ones are four-wave mixing (FWM) and spontaneous Raman scattering (SpRS/SRS). A detailed analysis of the impact of these and other phenomena on the quantum channel is discussed in articles [24; 25].  
While the FWM calculation is relatively straightforward and the interfering channel wavelength can be calculated by using the formula in [26], successful mitigation of the SpRS effect is much more challenging. The first step is to select the correct wavelength for all channels as described for Figure 1. This figure is based on the scattering characteristic measurements in papers [27; 28]. Alternatively, it is possible to place the quantum channel far beyond the area of Raman scattering. However, even proper channel placement may not be sufficient in most cases. If the classical channel is powerful enough (or if there are multiple such channels), it is likely that one of the methods described below might be necessary to use.
# Sensor Observation Service API for Providing Gridded Climate Data to Agricultural Applications
###### Abstract  
We developed a mechanism for seamlessly providing weather data and long-term historical climate data from a gridded data source through an international standard web API, which was the Sensor Observation Service (SOS) defined by the Open Geospatial Consortium (OGC). The National Agriculture and Food Research Organization (NARO) Japan has been providing gridded climate data consisting of nine daily meteorological variables, which are average, minimum, maximum of air temperature, relative humidity, sunshine duration, solar radiant exposure, downward longwave radiation, precipitation and wind speed for 35 years covering Japan. The gridded data structure is quite useful for spatial analysis, such as developing crop suitability maps and monitoring regional crop development. Individual farmers, however, make decisions using historical climate information and forecasts for an incoming cropping season of their farms. In this regard, climate data at a point-based structure are convenient for application development to support farmers' decisions. Through the proposed mechanism in this paper, the agricultural applications and analysis can request point-based climate data from a gridded data source through the standard API with no need to deal with the complicated hierarchical data structure of the gridded climate data source. Clients can easily obtain data and metadata by only accessing the service endpoint. The mechanism also provides several web bindings and data encodings for the clients' convenience. Caching, including the pre-caching mechanism, was developed and evaluated to secure an effective response time. The mechanism enhances the accessibility and usability of the gridded weather data source, as well as SOS API for agricultural applications.  
web API; standard API; point-based weather; long-term historical weather; gridded data source +
Footnote †: journal: Future Internet
## 2 Design and Implementation of On-Line PD Monitoring System
### Modules of Server Software
In Figure 24 the exemplary results of the 80-min registration of the surface discharges of average apparent charge \(q_{mean}=283\) pC and maximal \(q_{max}=5702\) pC are presented. A typical PRPD distribution for surface discharges was obtained. The most PD pulses were registered in the first (0-90\({}^{\circ}\)) and third quarter (180-270\({}^{\circ}\)) of a sine wave of test voltage. Figure 23: Schematic diagram of the measurement setup in which the monitoring system software module for performing PRPD patterns was tested: MS = partial discharge monitoring system, MPD = multichannel signal concentrator, S = server, PC = computer, U = high-voltage supply, Z = short-circuit current limiting resistor, TT = oil-filled transformer tank; PD = electrode system for partial discharge generation, C = coupling capacitor, CD = coupling device (measuring impedance), CC = connecting cable, M = conventional partial discharge measuring instrument. The results obtained by the prototype monitoring system (Figure 25) confirmed the properly implemented functions of PRPD pattern creation. In this case, also most of the pulses were registered in the first and third quarters of the voltage sine wave. However, compared to the IEC 60270 method (where the number of pulses did not depend clearly on the voltage polarization), both electromagnetic methods registered more pulses of positive polarization. Currently, there is work conducted on equipment of the analytical module in the function of automatic recognition of PD type based on the analysis of the PRPD patterns.
## 5 Applications
### Pharmaceuticals  
The quality control in the production of pharmaceutical tablets is strict, with tolerances of the amount of active pharmaceutical ingredient (API) of 1%. To secure that the production is providing pharmaceutical tablets with an API content within this narrow interval, typically random tablets are taken out in the production line for wet chemistry analysis. This analysis is time-consuming and labor intense. With results of the analysis available first after a long delay. If the tablet does not fulfill the quality control, it means that large batches of tablets have to be discarded due to the long analysis delay. Direct in-line optical spectroscopic analysis is considered a better technique, provided that the accuracy of the measurements can be sufficiently good. DOS, as well as Raman transmission spectroscopy [162; 163], are studied for such analysis. A complication is the highly scattering character of the tablets, providing a very long and spread path of the light as it propagates through a tablet. The scattering is caused by the porous character of the tablet, with changes in the refractive index as light propagates through the tablet. Any alterations in the size distribution of the filling material or the compression force in the production of the tablet will alter the light path as it passes through the tablet. This will cause alterations in measured DOS or Raman spectra, making precise absolute concentration measurements challenging.  
The biophotonics team at Lund University had a long-lasting collaboration with AstraZeneca in Molndal, Sweden to assess the potential of near-infrared photon time-of-flight spectroscopy (pTOF or TD-DOS) as a more sophisticated version of near-infrared spectroscopy (NIRS) to allow absorption spectra to be measured independent of the scattering properties of the tablet. Figure 23 shows the extraction of absorption and reduced scattering spectra of tablets with different scattering, showing that the scattering contribution is effectively eliminated by TD-DOS. In this way, the uncertainties caused by variations in scattering properties could be eliminated in the assessment of API concentration, and the scattering properties could be linked to the matrix properties of the tablet, related to releasing properties of the API, including the delay and duration of the release after swallowing the tablet. These measurements could be complemented by NIR gas spectroscopy to further asses the matrix properties of the tablets [162; 163; 164; 165; 166; 167; 168; 169; 170; 171; 172; 173].  
Figure 23: (**a**) Absorption and (**b**) reduced scattering spectra of measured tablets (black lines) with different scattering contribution, and of the pure ingredients of tablets (red, blue, green) [161].
# Crack Segmentation on Earthen Heritage Site Surfaces
## 5 Conclusions and Future Work
### Future Work  
According to the statistics generated from the experiments, the research methods and transfer learning ideas proposed in this paper have been proven to be effective. The models can only segment rammed earthen surface cracks, but the position, width, length, and depth of cracks are still uncertain, and thus, further optimization is needed. Moreover, the dataset of cracks on rammed earthen heritage sites is still small. More in-depth work is needed.  
1. Since the image data of surface cracks in earthen heritage sites is still relatively small, there are few studies on the deep learning of surface cracks in earthen heritage sites. Therefore, it is very important to collect a large amount of image data of surface cracks on earthen heritage site surfaces and build a larger dataset. In the future, UAVs can be used to collect crack images, and image cropping and annotating can be performed using the trained model to establish a dataset.
2. By sharing the dataset of cracks on the surface of heritage sites and uploading crack pictures in real-time, a larger database of crack pictures was established, which is convenient for researchers to study the cracks.
3. This study focused on the identification of cracks. Future work can be done regarding the location, length, width, and depth of cracks.
4. The current solutions, which cannot be deployed in lightweight embedded systems, were limited due to the complexity of the network. For practical application, models that can be deployed based on UAVs will be able to detect cracks more efficiently.  
Conceptualization, Y.Z. and Z.Z.; methodology, Y.Z. and Z.Z.; software, Y.Z. and Q.L.; validation, W.Z.; data curation, W.Z. and Q.L.; writing--original draft preparation, Y.Z.; writing--review and editing, Y.Z. All authors have read and agreed to the published version of the manuscript.  
This research was financially supported in part by the National Key Research and Development Program of China under Grant No. 2019 YFC1520904.  
Not applicable.  
The authors declare no conflict of interest.
## 3 Results and Discussion
In summary, the inoculation of the bacterial consortium had no significant effect on the studied quality parameters, which were more stable and/or influenced by different N doses. Although beneficial bacteria have the potential to improve plant growth and fertilizer uptake, excess nitrogen can induce sporulation and limit their metabolic activity at critical stages of crop development. This highlights the importance of properly managing nitrogen doses to maximize the benefits of microbial inoculants in crops. In this study, it was demonstrated that fertilization of 120 kg of N ha\({}^{-1}\) is more efficient (NUE: 44.32%) than the full fertilization dose of 240 kg of N ha\({}^{-1}\) (NUE: 27.51%) (Table 5), due to a lower amount of N fertilizer applied. Although the N derived from the fertilizer at physiological maturity (Figure 3) was quantitatively higher in the 240 kg N ha\({}^{-1}\) treatments (69.1 \(\pm\) 30.3 kg ha\({}^{-1}\) and 62.9 \(\pm\) 11.5 kg N ha\({}^{-1}\)) compared to the 120 kg of N ha\({}^{-1}\) treatments (52.4 \(\pm\) 7.6 kg ha\({}^{-1}\) and 54.0 \(\pm\) 23.2 kg ha\({}^{-1}\)), the difference was not statistically significant. \begin{table}
\begin{tabular}{c c c c c c c c c c c c c} \hline \hline  & \multicolumn{2}{c}{**Heedlifier Weight**} & \multicolumn{2}{c}{**1000 Crain Weight (g)**} & \multicolumn{2}{c}{**Protein (\%)**} & \multicolumn{2}{c}{**SDS Sedimentation Test**} & \multicolumn{2}{c}{**SDS/Protein Index**} & \multicolumn{2}{c}{**Wholesional Yellowness**} \\ \multicolumn{2}{c}{**Gh(m)**} & \multicolumn{2}{c}{**Standard**} & \multicolumn{2}{c}{**Mean**} & \multicolumn{2}{c}{**Standard**} & \multicolumn{2}{c}{**Mean**} & \multicolumn{2}{c}{**Standard**} & \multicolumn{2}{c}{**Mean**} & \multicolumn{2}{c}{**Standard**} & \multicolumn{2}{c}{**Mean**} & \multicolumn{2}{c}{**Standard**} & \multicolumn{2}{c}{**Mean**} & \multicolumn{2}{c}{**Standard**} \\ \hline N Level, Ng N & 0 kg N ha\({}^{-1}\) & 78.85 a & 0.13 & 57.94 b & 0.42 & 9.20 a & 0.16 & 11.31 a & 0.17 & 1.25 b & 0.02 & 14.23 a & 0.06 \\ ha\({}^{-1}\)(A) & 20 kg N ha\({}^{-1}\) & 80.80 b & 0.13 & 58.08 b & 0.42 & 11.09 b & 0.16 & 11.29 a & 0.16 & 12.02 a & 0.02 & 14.52 b & 0.06 \\ Bacterial & Uninoculated & 80.48 a & 0.11 & 57.69 a & 0.35 & 10.58 a & 0.13 & 11.49 a & 0.14 & 1.10 a & 0.01 & 14.53 a & 0.05 \\ consortium (B) & Inequivalent & 80.52 a & 0.11 & 57.40 a & 0.35 & 10.82 a & 0.13 & 11.68 a & 0.14 & 1.10 a & 0.01 & 14.43 a & 0.05 \\ A \(\times\) B & \(\mathrm{F}\mathrm{u}\mathrm{x}\mathrm{x}\mathrm{x}\mathrm{x}\mathrm{x}\mathrm{x}\mathrm{x}\mathrm{x}\mathrm{x}\mathrm{x}\) & 0.72 & 3.03 & 0.483 & 0.57 & & 0.57 & & 0.12 \\  & \multicolumn{2}{c}{} & 0.071 & 0.0033 & 0.4583 & 0.4828 & 0.4056 & 0.4881 & 0.48 & & 0.065 \\ \hline \end{tabular}
\end{table} 
Table 4: Wheat quality traits of the studied treatments.
# A Novel RPL Algorithm Based on Chaotic Genetic Algorithm
## 3 RPL-Cga
### Outlines of RPL-Cga  
The outlines of RPL-CGA are as follows:  
1. Analyzing CGA.
2. Analyzing the requirements that RPL routing metrics should meet.
3. Proposing which routing metrics should be considered in RPL-CGA.
4. Proposing novel composition metric and objective function.
5. Using the chaotic genetic algorithm to optimize the weighting factor of each routing metric in the composition metric.
6. Calculating rank values of nodes according to the newly-proposed objective function.
7. Choosing the preferred parents based on rank values of nodes.  
In what follows, the details of RPL-CGA are described according to the abovementioned seven sections.
# A Novel Hybrid Ant Colony Optimization for a Multicast Routing Problem
## 2 Problem Description
To guarantee the existence of feasible paths, the minimum residual bandwidth on any edge along \(p_{T}(s,d)\) must satisfy Constraint (4). Let \(J_{d}\) (jitter) be the packet delay variation, and \(PL_{d}\) the packet loss rate. Constraint (5) ensures that the jitter sum on \(p_{T}(s,d)\) cannot exceed the predefined upper limits. Constraint (6) is the constraint of packet loss. The goal of this study is to minimize costs of \(T(s,M)\) in total. As we shall see, the ACO is flexible enough to handle more complicated objectives.
## 3 Theoretical Background and Method  
### Phase Mismatch in 90\({}^{\circ}\) Optical Hybrid  
The 90\({}^{\circ}\) optical hybrid is a key component to provide the phase diversity of an optical coherent receiver. It combines two input signals (an incoming signal and a local oscillator reference signal) and generates four optical signals with a 90\({}^{\circ}\) phase difference. However, the phase difference of the two output signals may be deviated from 90\({}^{\circ}\) when the optical hybrid is imperfect. This quadrature imbalance causes phase errors in the output photocurrents. Phase offset from 90\({}^{\circ}\) is called a phase mismatch. There are different ways of modeling the IQ phase mismatch effect. One formalism is to relate a complex signal having phase mismatch imbalance \(\{I^{\prime}(t)+jQ^{\prime}(t)\}\) with its ideal signal \(\{I(t)+jQ(t)\}\) in the form of ([PERSON], 2007)  
\[I^{\prime}(t)+jQ^{\prime}(t)=\big{[}Imb_{\text{J}}I(t)+Imb_{\text{Q}}Q(t) \big{]}e^{i(\frac{\pi}{2}+\phi_{\text{IQ}})} \tag{4}\]  
where \(\phi_{\text{IQ}}\) is the quadrature phase mismatch. The impact of the IQ phase mismatch imbalance for different modulation formats is summarized in ([PERSON], 2007). The system performance will degrade significantly if IQ phase mismatch is not compensated.  
Figure 1: Schematic of a free-space optical communication (PSO) system. CW: continuous-wave laser, MZM: Mach–Zehnder modulator, EDFA: Erbium-doped fiber amplifier, OBPF: optical bandpass filter, PC: polarization controller, TIA: transimpedance amplifier, ADC: analog-to-digital converter, DSP: digital signal processing.