esa-sceva/satcom-chunk-collection huggingface dataset:
## 4 Results  
### HJ and MODIS Fusion Results  
By inputting a base HJ CCD image, two days of MOD09 GA data and two days of multi-spectral HJ CCD images, a synthetic multi-spectral HJ CCD image was generated by STDFA. By inputting a base HJ CCD image, two days of multi-spectral MOD09 GA data and two days of multi-spectral MODIS data and HJ CCD datasets, a synthetic multi-spectral HJ CCD image was also generated by ESTARFM. These synthetic multi-spectral HJ CCD images contained four bands, including blue, green, red and NIR. Figure 2a shows the actual observed MODIS surface reflectance in the red band acquired on 7 October 2013 in Kuche and Luntai. Figure 2b,c show the synthetic surface reflectance imagery in the red band generated by STDFA and ESTARFM, respectively, for the two study areas. Figure 2d shows the actual observed HJ CCD red-band surface reflectance acquired on 7 October 2013 in Kuche and Luntai.  
Figure 2: Comparison of MODIS, HJ CCD and synthetic data generated by the ESTARFM and STDFA acquired on 7 October 2013: (**a**) MODIS data; (**b**) synthetic HJ CCD data generated by STDFA; (**c**) synthetic HJ CCD data generated by ESTARFM; (**d**) actual HJ CCD data.  
The actual high spatial resolution data acquired on 7 October 2013 was used to evaluate the accuracy of these models. Through visual interpretation, we found that the synthetic and actual HJ CCD data are very similar, and were hard to distinguish between with the naked eye. Table 4 shows the results of the quantitative evaluation using the correlation analysis method. From Table 4, we can see that both STDFA and ESTARFM can generate synthetic HJ CCD data that are very similar to actual HJ CCD data, with \(r\) values greater than 0.8989. STDFA showed a slightly better performance than ESTARFM for Luntai and Kuche.
# Design of an Axial Turbine for Highly Downsized Internal Combustion Engines
## 2 Background of Turbochargers
### Aerodynamics  
The aerodynamics of turbomachinery are strictly dependent on the type of machine selected for an application: radial, axial or mixed flow. In this regard, axial machine (which are the focus of this work) cascade aerodynamics will be the main focus in the design of the blades. Cascades are the series of airfoils obtained by cutting the turbomachine with a conical/cylindrical surface coaxial with the machine rotation axis. Flattening the cascade surface, it is common practice to analyze the flow with virtual velocity triangles obtained by the composition of the actual flow velocity (in the inertial frame) \"hitting\" the rotor and the rotational velocity of the rotor itself in order to design the airfoil for the relative flow velocity and angle.  
Two main types of turbines can be used for this type of application: impulse or reaction turbines. The former does not have any pressure change in the rotor, which spins because of the change in direction of a high-velocity flow due to the curvature of the blade; the latter type distributes the pressure drop both in the stator and rotor, while the rotor does not change the direction of the flow as much as impulse turbines, but is nozzle-shaped. Moreover, reaction turbines are mainly used for machines that must develop torque from a high-pressure fluid. For this reason, the reaction turbine type is the preferred choice for the considered application.  
The aerodynamic design of modern turbomachines could be split into three major parts: preliminary design, 1D-2D meanline and streamline analysis and optimization, profiling, blade design and final 3D analysis. This process will be further described in the methodology section; however, as the preliminary design and 1D-2D analyses are based on thermo-fluid-dynamic and simplified mechanical calculations, it is important to model the performance with empirically based loss models accounting for phenomena such as profile losses, tip losses, stalling and so forth.
# PerHelper: Helping Developers Make Better Decisions on Permission Uses in Android Apps
## 3 A Taxonomy of Permission-Related Issues
### Concepts and Definitions  
We first define the following concepts related to Android permissions, which will be used throughout this paper.  
* A _declared permission set (DPS)_ contains all the permissions declared in the Android Manifest file of an app by the developer.
* A _used permission set (UPS)_ contains all the permissions required by all the APIs that may be invoked during the execution of a particular Android app. We can divide this set into two subsets, the set that contains the used permissions for the code written by developers (UPS\({}_{dev}\)) and the set that contains the used permissions for the third-party libraries included in the app (UPS\({}_{lib}\)). It is not difficult to know that: \[UPS=UPS_{dev}\cup UPS_{lib}\] Please note that there might be overlaps between these two sets as one permission might be used both in the developer's code and library code.  
The perfect scenario would be when \(DPS\)equals \(UPS\), which ensures not only that all the data accesses protected by permissions work well, but also that there are no unused permission declarations that might introduce various security threats. On the contrary, If \(DPS\) does not equal \(UPS\), there exists a permission gap between the declared and the used permissions.  
There are three types of permissions issues we focus on in this paper.  
* _Permission overprivilege_ occurs in an app when \(|DPS-UPS|>0\). This means the app declares more permissions than it actually uses. An app with permission overprivilege violates _the principle of least privilege_ (POLP) [10], which may introduce potential security vulnerabilities.
* _Permission underprivilege_ occurs in an app when \(|UPS-DPS|>0\). This means the app uses more permissions than it declares. As a matter of fact, permission underprivilege happens much more often than we expect. We will discuss this later.
* An _unprotected API_ occurs when developers forget to add an exception handler to some API methods, which may throw exceptions. Figure 1 is an example code snippet in which developers failed to protect a privileged API, so that the app would crash if the API were called.
# Bone Temperature Variation Using a 3D-Printed Surgical Guide with Internal Irrigation
## 2 Materials and Methods  
### Study Design  
In this ex vivo experiment, a 3D-printed surgical guide provided with built-in irrigation tubes for supplementary internal irrigation was tested. Bone temperature was recorded during osteotomy preparation. The workflow of the study is presented in Figure S1. Twelve fresh bovine ribs were used to conduct the study. The specimens were acquired from a local butcher shop and stored at \(-18~{}^{\circ}\)C. They all had the soft tissue removed before the initiation of the experiment.
# Deep Learning-Based Layout Analysis Method for Complex Layout Image Elements
## 2 Film Poster Composition Layout Method  
At present, there is no uniform view in the academic world on the compositional layout of film posters, so there are various methods of classification. This study combines the existing rules of poster layout design composition and typography, and summarizes film poster images into the following eight commonly used types: centered layout, split layout, symmetrical layout, diagonal layout, wraparound layout, full-screen layout, axial layout, inclined layout, and other compositional layouts.  
Centered layout will be the main elements in a centrally aligned manner, can quickly attract the eye to occupy the visual focus, as shown in Figure 1a. The split layout arranges the poster in an asymmetrical structure with the figure above the text below and the figure below the text above, ensuring a balanced and stable picture and forming a sharp contrast, as shown in Figure 1b. The symmetrical layout arranges the main elements in a symmetrical manner relative to the central axis, visually giving a feeling of rigor and rationality, as shown in Figure 1c. The diagonal layout distributes the main elements of the poster in opposite corners, adding an unstable variation that can bring a visual impact, as shown in Figure 1d. The surrounding layout is generally a graphic surrounded by text, its composition form is fuller, more information, as shown in Figure 1e. The full-screen layout is mainly graphics to support the entire layout, supplemented by text, visually give people an intuitive and strong feelings, as shown in Figure 1f. The axis layout is dominated by a hidden axis, arranging the main elements in a hidden axis to break the limitations of a centered layout and make the layout appear less dull, as shown in Figure 1g. The tilt layout mainly arranges the main elements of the poster in a tilted manner, giving a sense of visual motion and instability, as shown in Figure 1h. In practical examples, it is difficult for some posters to generalize and define the characteristics of a layout, and it may be difficult to fit into a certain layout classification. In order to simplify the analysis, this study categorizes posters that are disorganized, free-layout posters, or posters that are laid out in other layout styles within the Other Layout category. The first eight ways encompass most of the current ways of laying out a film poster.  
Figure 1: Schematic diagram of the poster layout. (**a**) Centered layout; (**b**) split layout; (**c**) symmetrical layout; (**d**) diagonal layout; (**e**) wraparound layout; (**f**) full-screen layout; (**g**) axial layout; (**h**) inclined layout.
###### Abstract  
Potential changes in both the intensity and frequency of extreme drought events are vital aspects of regional climate change that can alter the distribution and dynamics of water availability and subsequently affect carbon cycles at the ecosystem level. The effects of extreme drought events on the carbon budget of peatland in the Zoige plateau and its response mechanisms were studied using an in-field controlled experimental method. The results indicated that the peatland ecosystem of the Zoige plateau functioned as a carbon sink while under the control (CK) or extreme drought (D) treatment throughout the entire growing season. Maximum fluxes of methane (CH\({}_{4}\)) emissions and the weakest carbon sink activity from this ecosystem were in the early growth stage, the most powerful carbon sink activity was during the peak growth stage, while the absorption sink activity of carbon dioxide (CO\({}_{2}\)) and CH\({}_{4}\) was present during the senescence stage. Extreme drought reduced the gross primary productivity (GPP) and ecosystem respiration (R\({}_{e}\)) of the peatland ecosystem by 14.5% and 12.6%, respectively (\(p<0.05\)) and the net ability to store carbon was reduced by 11.3%. Overall, the GPP was highly sensitive to extreme drought. Moreover, extreme drought significantly reduced the CH\({}_{4}\) fluxes of the ecosystem and even changed the peatland from a CH\({}_{4}\) emission source to a CH\({}_{4}\) sink. Subsequent to drought treatment, extreme drought was also shown to have a carry-over effect on the carbon budget of this ecosystem. Soil water content and soil temperature were the main driving factors of carbon budget change in the peatland of the Zoige plateau, but with the increase in soil depth, these driving forces were decreased. The findings indicated that frequent extreme drought events in the future might reduce the net carbon sink function of peatland areas, with an especially strong influence on CO\({}_{2}\).  
extreme drought; alpine peatland; carbon budget; controlled experiment +
Footnote †: journal: Nuclear Instruments
## 4 Simulation and Hardware-in-the-Loop Results
### Simulation Studies
#### 4.1.2 Short-Term Simulation  
To test the wind system with the designed controller, a study was performed to validate the proposed method, using a detailed model of the whole system. The proposed WT system and control scheme shown in Figure 4 was modeled in Matlab/Simulink.  
The aim of this short-term simulation was to validate the performance of the proposed algorithm, and examine its accuracy and response to wind variation. Therefore, the approach should give the reference for the pitch angle and rotor speed as quickly as possible.  
In this simulation study, the wind speed was scaled to be in seconds instead of minutes. The wind turbine system was tested with the wind profile shown in Figure 11. Like the one-day simulation, in order to demonstrate the performance of the proposed de-loading algorithm, two different approaches were performed, with different methods of de-loading. First, the rotor speed only was used as a tool to maintain the reserved power. Then, the proposed de-loading approach was implemented using the same wind profile for the purpose of comparison.  
Initially, the MPPT was implemented to be used as a baseline. Then two scenarios discussed in the previous section were examined. Figure 12 shows the maximum and de-loaded power for the two methods. The rotor speed for the different methods are demonstrated in Figure 13. Both approaches provide the same amount of reserve power (\(\Delta P\)). As a one-day simulation, the reserve was fixed at 0.3 MW for all wind speeds. For the rotor speed method, the rotor speed was reduced compared to the  
Figure 11: Wind profile (short-term simulation).  
Figure 10: The pitch angle with a wind forecast and without a wind forecast.  
The high current on the stator causes an increase in the resistive losses and conduction losses, as demonstrated in Table 2. The table presents the averaged resistive losses and conduction losses for the whole period (240 s). The resistive losses are calculated using Equation (6), where the \(d\)-axis current is controlled to be fixed at 0 A. The IGBT characteristics were taken from the ASEA Brown Boveri (ABB) data sheet that matches the rating of the WT system, (5 SNA 3600E170300 HiPak IGBT module). The conduction losses were calculated using web-based software (SEMIS) developed by Plexim (Zurich, Switzerland) for ABB data-sheet characteristics, in order to consider the detailed thermal module of the converter.
## Appendix A All Constraints in an MILP Formulation for Rank-2 Chemical Graphs
### Construction of Scheme Graph and Tree-Extension  
We infer a subgraph \(H\) such that the maximum degree is \(d_{\max}\in\{3,4\}\), \(n(H)=n^{*}\), \(\text{cs}(H)=\text{cs}^{*}\) and \(\text{ch}(H)=\text{ch}^{*}\). For this, we first construct the \((t^{*},\text{ch}^{*},d_{\max})\)-tree-extension of the scheme graph \((K=(V_{K}=\{u_{1},\ldots,u_{s^{*}}\},E_{K}=\{a_{1},a_{2},\ldots,a_{m}\}), \mathcal{E}=(E_{1},E_{2},E_{3}))\). We use the following notations: For \(j\in[1,3]\) and \(s\in[1,s^{*}]\), let \(E_{j}^{+}(s)\) (resp., \(E_{j}^{-}(s)\)) denote the set of indices \(i\) of edges \(a_{i}\in E_{i}\) such that the tail (resp., head) of \(a_{i}\) is \(u_{s,1}\). Let \(E_{j,k}^{+}(s)\triangleq E_{j}^{+}(s)\cup E_{k}^{+}(s)\), \(E_{j,k}^{-}(s)\triangleq E_{j}^{-}(s)\cup E_{k}^{-}(s)\), \(E_{j}(s)\triangleq E_{j}^{+}(s)\cup E_{j}^{-}(s)\) and \(E_{j,k}(s)\triangleq E_{j}(s)\cup E_{k}(s)\). As described in Section 2.3.1, some edge \(a(i)\in E_{1}\cup E_{2}\) may be replaced with a subpath \(P_{i}\) of \((v_{1,1},v_{1,2},\ldots,v_{r^{*},1})\), which consists of the roots of trees \(T_{1},T_{2},\ldots,T_{r^{*}}\). We assign color \(i\) to the vertices in such a subpath \(P_{i}\) by setting a variable \(\chi(t)\) of each vertex \(v_{t,1}\in V(P_{i})\) to be \(i\). For each edge \(u_{s,1}v_{t,1}\), we prepare a binary variable \(e(s,t)\) to denote that edge \(u_{s,1}v_{t,1}\) is used (resp., not used) in a selected graph \(H\) when \(e(s,t)=1\) (resp., \(e(s,t)=0\)). We also include constraints necessary for the variables to satisfy a degree condition at each of the vertices \(u_{s,1},s\in[1,s^{*}]\) and \(v_{t,1}\), \(t\in[1,t^{*}]\).
## 4 Role of sRNA in Antibiotic Resistance
### Inhibiting Drug Uptake Systems  
As detailed in the previous paragraphs, antibiotics enter bacterial cells through various mechanisms, ranging from simple diffusion to energy-dependent transport. To hinder antibiotic entry, certain bacteria employ sRNAs that target membrane proteins involved in antibiotic uptake, as discussed in the following section.
## 2 Materials and Methods
### Overview of Methodologies  
As shown in Figure 3, we first calculated the pentad mean SM, meteorological variables, and SIFs based on daily values. The identification of flash droughts with specific four cases was performed based on the pentad mean SM. We then explored the frequency and duration characteristics of flash droughts in the agricultural areas of southern China. Next, we investigated the meteorological characteristics under flash drought conditions, and then analyzed the response characteristics of SIF to flash droughts. Finally, we explored the response characteristics of vegetation photosynthesis capacity to flash droughts by analysis of a typical event in 2019.  
Figure 2: Illustration the definitions of flash drought with minimum durations based on SM percentiles. (**a–d**) denote Case 1, Case 2, Case 3, and Case4, respectively.
## 5 Simulation Experiments
### Simulation Results
#### 5.2.1 SD-EAR versus LEACH, SPIN  
LEACH divides the sensor network into multiple clusters. The technique for electing a cluster-head is the main source of energy efficiency here. If a node has already played the role of a cluster-head in several runs, then its chance of becoming a cluster-head in the next run again reduces greatly. This encourages the rolling of cluster-heads by the balancing load. However, LEACH does not consider the location of sensor nodes [35; 36; 43] and therefore, certain cluster members may stay very far from the cluster-head. So, the energy consumed by the cluster-head in transmitting a message to those members that are located far, increases substantially. Also, LEACH applies [PERSON]'s shortest path algorithm to select the optimum path [43]. The authors would like to state here that shortest path, in most cases, is not the most energy-efficient one. Hence, the performance improvement produced by SD-EAR over LEACH is noteworthy. This is evident in Figures 11-15.  
SPIN [38] is also a very important energy-efficient protocol that broadcasts metadata, which is data about data. If a neighbor develops interest about actual data after receiving the metadata, only then is data sent to it. The energy efficiency in SPIN arises from the size of the metadata being much less than the size of the actual data, and the actual data is sent to a subset of neighbors instead of all of the neighbors, as in an ordinary broadcast.  
On the other hand, in SD-EAR, the broadcasting of an opt-route-select is not performed, not even in inter-zone communication. Actually, in the inter-zone route discovery, opt-route-select is at most multicast to all of the peripheral nodes, as well as also through energy-efficient paths, as instructed by the SDN controller in that zone. Those routes do not break easily, and the requirement of route-rediscovery arises significantly less in our proposed protocol, which reduces the message cost in SD-EAR compared with LEACH and SPIN, as seen from Figure 11.
###### Abstract  
In light of the challenges posed by the complex structural characteristics and significant coupling of vibration signals in rotating machinery, this study proposes an adaptive noise reduction method called Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN). Additionally, an enhanced threshold screening Singular Value Decomposition (SVD) algorithm is introduced to address the issues pertaining to noise identification and feature extraction in the context of vibration signals from rotating machinery, which are subjected to complex noise interference. The effectiveness of the proposed approach is substantiated through the evaluation of key metrics, such as the signal-to-noise ratio (SNR), as well as the utilization of advanced signal analysis techniques, including Short Time Fourier Transform (STFT) and Continuous Wavelet Transform (CWT). The experimental results validate the finding that the combination of the improved CEEMDAN and the enhanced threshold screening SVD algorithm effectively reduces noise interference in vibration signals from rotating machinery. This integrated denoising approach successfully preserves the informative characteristics of the vibration signals, thereby laying a foundation for the subsequent fault diagnosis of rotating machinery.  
vibration signals; complete ensemble empirical mode decomposition with adaptive noise; singular value decomposition
# Dynamic Modeling and Altitude Control for Flying Cars Based on Active Disturbance Rejection Control
## 6 Conclusions  
In this paper, to realize accurate altitude control of a flying car, we first built a dynamic model of a flying car comprising a body model, motor model, and propeller model. Then, a double-loop controller based on active disturbance rejection control was designed to accurately control the flight altitude and compensate for unknown external disturbances. Then, detailed simulation results were presented. Through simulation and tests, the model was verified. A simulation of the altitude control was also carried out. In the simulation, the proposed method showed excellent control effectiveness. Finally, based on the detailed simulation results, actual flight tests were carried out. The proposed method was compared with a PID controller. In the flight test, it was observed that the proposed method had better control effectiveness, capacity to resist disturbances, and convergence velocity. The results prove that the proposed method represents a novel method for the altitude control of a flying car and shows broad application prospects.  
Besides the disturbances in this paper, there exist time-varying wind disturbances and coupling influences between different propellers. All unknown disturbances need to be considered in the controller design. In future work, we expect to adopt the active disturbance rejection control method. By using an extended state observer, the unknown disturbance can be regarded as an extended state, which can be dynamically compensated for. This is the main research direction for our next work.  
Methodology, W.L. and H.S.; Investigation, J.X.; Resources, Z.L.; Data curation, Y.X.; Funding acquisition, X.L. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the National Natural Science Foundation of China (Grant No. 62003177).  
Not applicable  
Not applicable.  
The raw data supporting the conclusions of this article will be made available by the authors on request.  
Figure 13: Flight experiment using the proposed method for altitude control. (**a**) Thrust. (**b**) Flight altitude.  
**Conflicts of Interest:** The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.