esa-sceva/satcom-chunk-collection huggingface dataset:
## 1 Introduction  
### Background and Formulation of the Problem  
Rotating machines, such as steam turbine generators, turbine compressor units, pumps, etc., play a critical role in industry and are widely used. The rotor-bearing system (rotor) is the main element in rotating machines. Rotor unbalance is a typical fault of rotors. It is inevitable due to errors in manufacturing, installation, and operation. Vibrations and even sudden breakdowns can be caused because of rotor unbalance. Identifying rotor unbalance (amplitude and phase angle) is necessary for balancing rotors to reduce vibrations and ensure the safety of rotating machines. In view of these issues, rotor unbalance estimation, which is one inverse problem of rotor dynamics, has been an active area of research.  
Although rotor unbalance can be estimated so that a rotor can be balanced off-site using a dynamic balancing machine in the laboratory, complex processes, such as uncovering, dismantling, and transporting, are required. The whole process is time-consuming and expensive and is difficult to implement, especially for large rotors. Hence, monitoring rotor unbalance on-line, by which means balancing time and cost can be reduced, is very important.
## 1 Introduction
On the contrary, if only pursuing high useful data rate, little margin could be reserved to compensate the atmospheric attenuation, which will result in smaller link availability, especially for small elevation angles, and the outage period might be so long and seriously affect the user's data receiving task. Therefore, there should be a balance between the useful data rate and the link availability to maximize the transmission efficiency of LEO EO satellites, and this is the basis of the TEF proposed in this paper. In this paper, we propose an innovative and contributive solution for the evaluation of the satellite-to-ground transmission efficiency and the scheme design of space-borne systems. The main novelty and contributions of this paper are summarized as follows:  
1. The TEF of LEO EO satellites is proposed for CCM, VCM and ACM, which is defined by considering the link availability, useful data rate and the transmission arc segment of G/S. TEF could be utilized as a quantitative index for scheme selection. 2. A new analysis method is developed for the evaluation of the satellite-to-ground transmission efficiency, taking weather characteristics, transmission systems and other factors into account. Three G/Ss with representative weather conditions are selected in this paper in order to reach the conclusions for various application scenarios. The rest of this paper is organized as follows: Section 2 presents the system model and configuration of LEO data transmission system, including the definition of TEF, the optimum selection of MCSs and other simulation parameters. In Section 3, the satellite-to-ground data transmission efficiency of CCM, VCM and ACM are analyzed quantitatively. Section 4 compares the transmission efficiency and completes the scheme design of satellite-to-ground data transmission. Section 5 concludes the paper.
# Efficient Key-Value Data Placement for ZNS SSD
## 4 Design
### Lifetime-Based Zone Allocation  
Figure 8 shows the zone allocation method according to the lifetime. Let us suppose that we assign a zone to write Extent #0 for Zonefile #2 in Figure 8. First, we check the status of each zone from Zone #0 in order. Zone #0 is excluded from the candidate zone list for zone allocation, because all areas have been exhausted. Since Zone #1 has a free page, we compare its write lifetime hint (WLTH_EXTREME) declared by the host to the write lifetime hint (WLTH_SHORT) of Zonefile #2 containing Extent #0. If the lifetime is the same, that zone is assigned. However, as we can see in Figure 8, Zone #1 is excluded due to the lifetime being different. Finally, Zone #2 is an entirely empty zone and is not assigned any write lifetime hint from the host; therefore, it is assigned as a zone for writing the Extent #0 of Zonefile #2. As a precaution, regardless of zone order, zones with the same lifetime as the requested data and with some vacancies are allocated prior to empty zones.  
Such a method induces one zonefile to be placed in the same zone as much as possible. Moreover, even if different zonefiles are placed in a single zone, this does not mix the different lifetime zonefiles; therefore, physical deletion is not delayed. This effectively solves the problem of physical deletion delays due to zonefiles with different lifetimes being mixed into one zone. It reduces the valid data copying amount and enhances the performance.
# Real-Time Indoor Positioning Approach Using iBeacons and Smartphone Sensors
## 2 Related Work  
### RSS-Based Method  
In this section, we shortly review the current solutions for indoor positioning regarding iBeacons and PDR. RSS-based methods can be roughly categorized into fingerprinting and ranging-based methods (e.g., trilateration [3; 16]). In general, fingerprints or the radio map contains NLOS information of the environment, although its update costs some efforts [17]. The accuracy of fingerprinting depends on the number of BLE beacons for computation [18]. Specifically, multiple channels used by BLE beacons result in RSSI variation in a wider range than WiFi APs [19]. Researchers propose a method of batch filtering to mitigate the multipath effect of RSS. In another related study [11], the researchers set a window for batch filtering, and get the best performance (around 2.6 m for 90% of the time) with dense configuration of beacons. Sparse configuration of beacons result in the error of less than 4.8 m. In the same testbed, WiFi-based positioning involves an error of less than 8.5 m for 95% of the time.  
Another group of methods focuses on the automation of fingerprint generation [20] or crowdsourcing [8; 21]. These methods aim to automate the collection and update of fingerprints (i.e., radio map) [22; 23]. Users can provide feedback to boost the matching accuracy of WiFi fingerprinting. However, these methods always have low stability.  
In contrast, ranging-based methods estimate the coordinates of the receiver with transformed distances from RSSI, and they are prone to incorrect estimates due to the low ranging accuracy [16]. The accuracy of RSSI is influenced by many factors such as obstruction of walls, NLOS, multipath effect, etc. As low ranging accuracy is the bottleneck, we add a weight matrix to the iterative algorithm of trilateration [15] to stress the importance of near iBeacons for ranging. In this paper, we leverage the NLOS information in iBeacon fingerprints to correct the trilateration results. Our tests show the positioning accuracy is competitive with other RSS-based methods of WiFi or iBeacon.
## 5 Discussion  
### Problems of DEM based on Pleiades Data in High Mountain Areas  
A general problem of optical remote sensing data is the possibility of cloud cover during the time of acquisition. It is possible to specify a cloud cover of less than 5% of the area of interest for the Pleiades acquisition, but of course, even a low percentage of cloud cover can obscure important parts in the acquired images, e.g., the location of ground control points or objects that are to be studied. A low accepted percentage of cloud cover for a planned acquisition will also lower the  
Figure 19: One-year surface elevation change of the five investigated glaciers in the Khumbu Himal. These were calculated once from spring 2015 to spring 2016 and once combined with the surface elevation changes of the spring 2015-autumn 2015 and autumn 2015-spring 2016 periods. The highest parts of Nøozumpa glacier where data quality is problematic are marked in blue.  
chance of an actual acquisition taking place, since the operating company of the satellites will only acquire images if the feasibility of meeting the parameters of the order (including cloud cover) is high. While this is less problematic in areas with rather predictable weather conditions, such as the Nepalese Himalayas with their seasonal climate, it is harder in the Alps or in tropical areas with frequent cloud cover throughout the year. Nevertheless, in the Khumbu Himal study site, meeting the cloud cover criteria resulted in seasonal acquisitions that spanned several dates, which brings data processing and mosaicking challenges.  
Fresh snow can also be problematic for the calculation of DEM based on optical stereo data in several ways. The low contrast of the white snow surfaces leads to fewer matches being identified within the matching algorithm and therefore more gaps, outliers, and higher noise levels in the data over bright snow-covered areas. Of course, with snow covering the ground, the snow surface will be represented in the DEM, and this will be located above the real terrain surface as the snow fills terrain structures such as holes or furrows. This can lead to significant differences in rugged mountain areas, where large amounts of snow can accumulate in some areas due to topography and wind drift. This makes it crucial that data is acquired during minimum snow-cover conditions if the goal of the study is the accurate detection of glacier surface elevation changes and the correct calculation of volume changes of glaciers.  
Unfrozen water bodies are also problematic, since their surface changes between the taking of the stereo images, which is problematic for the matching algorithm. This leads to either missing or an erroneous elevation values for water bodies. Since there are many ponds on the heavily debris-covered tongues of the glaciers in the Khumbu Himal, this has to be considered.
# Investigation of THz Absorptive Signatures in Opioids
## 1 Introduction  
The portion of the electromagnetic spectrum with wavelengths spanning from 100 microns to 1 mm is the terahertz (THz) region. A chemical or biochemical sample under test (SUT) in the form of powder may consist of a large number of microcrystals. Each microcrystal contains multiple identical cells. Atoms in a unit cell may participate in collective vibration modes, which may be optically active to certain THz frequencies, leading to absorptive electromagnetic signatures. They can be unique, like fingerprints, which are used to identify the underlying material of SUT [1; 2; 3; 4]. Such a spectroscopic approach has been explored to detect illicit drugs [5; 6; 7; 8; 9; 10; 11; 12; 13].  
In the past decade, opioid abuse has gradually become an epidemic. Fentanyl, a synthetic opioid, is 50 to 100 times more potent than morphine [14]. It is dangerous not only to the victims but, if containing a toxic dose, could be harmful to first responders, emergency care facilities, and law enforcement alike. There were reports that nurses or police officers passed out after being accidentally exposed to fentanyl powder. Therefore, there are at least two urgent needs to develop rapid, non-contact, spectroscopy-based methods. One is for detecting drugs laced with fentanyl. Some illicit street drugs, such as cocaine and heroin, may contain fentanyl unaware to users for its lower cost of producing pleasure. This leads to many tragic deaths by fentanyl overdose. In 2020, synthetic opioid-related death reached a stunning 57,500, according to [15]. There was a recent report on using surface-enhanced Raman spectroscopy to detect fentanyl mixed into heroin [16], but reports on THz/millimeter-wave sensing opioids are still lacking to date. The other is for inspecting packages that may contain smuggling opioids by customs and post office. Sensing concealed cocaine in FedEx packages with a THz wave was investigated previously [7], but detection of fentanyl in the mail has not been investigated yet to the best of our knowledge.  
This research is to investigate the possibility of a fast, label-free, non-contact (THz) spectroscopic method for detecting fentanyl. Here we take a baby step by focusing on oxycodone, by treating it as a surrogate of fentanyl, which is a highly toxic substance that cannot be tested in our lab. Oxycodone, a semi-synthetic opioid, has been commonlyused as an effective alternative to morphine for extreme pain management [17]. Oxycodone overdose contributes to the opioid pandemic too, because the drug is abused for recreation. Since oxycodone is a controlled substance, we used oxycodone tablets in our preliminary studies.  
Pharmaceutical opioids contain inactive \"filler\" or \"carrier\" materials, such as lactose monohydrate, which are designed to improve ingestion into the human body. Therefore, these tablets are also good \"mimics\" of street drugs mixed with synthetic opioids.
## 6 Conclusions and Future Perspectives
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Mechanism/Response** & _E. coli_ & **Key References** & _L. monocytogenes_ & **Key References** \\ \hline
**pH homeostasis** & & & & \\  & GAD system & [13; 14; 118; 123] & GAD system & [15; 23; 25; 26] \\  & ADI system & [31; 32; 119; 124; 125] & ADI system & [16; 17; 33] \\ Proton consuming reactions & & & & \\  & & & & \\  & & & & \\  & & & & \\  & & & & \\  & & & & \\  & & & & \\  & & & & \\ \hline
**Protection and repair** & & & & \\  & Membrane composition & CFAs & [52; 53; 54; 55; 56; 57; 58] & BCFAs & [58; 59] \\  & Chaperones & HdeA, HdeB & [62; 63; 67; 68] & DnaK & [70] \\  & Hsp3I & [69] & & \\  & Dps & [72; 74; 76] & Fri & [80; 81; 82; 84] \\ DNA damage & SOS response & [86; 87; 88] & SOS response & [89] \\ \hline
**Sensing and regulatory** & & & & \\  & EvgAS & [95; 96; 97; 98; 99] & & \\  & PhcQ-PhoP & [99] & LisRK & [137] \\  & CpxRA & [60] & & \\  & Sensory hub & & & \\  & Alternative Sigma factors & RpqS & [91; 92] & SigB & [8; 106] \\  & Regulators & GadE ‘circuit’ & [100; 101; 102; 103] & ArgR & [16; 135] \\ \hline
**Response to short-chain organic acid** & & & & \\  & Lactic acid & [152] & & [109; 153; 155] \\  & Acetic acid & [144; 155; 156; 157; 158; 158] & & [40; 41; 153] \\  & Benzoic acid & [160; 161] & & [162] \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Summary of mechanisms deployed by _E. coli_ and _L. monocytogenes_ to cope with acid stress. within the sensing mechanisms used to detect the acidic environments. Whereas _L. monocytogenes_ is capable of sensing acid stress through the stressosome, _E. coli_ lacks this supramolecular complex and relies mainly on the EvgSA two-component system to detect low pH and activate the signal transduction pathways that leads to the upregulation of acid stress response genes. Overall, this field still has important unanswered questions that, if addressed, have the potential to give major new insights into the biology of these bacteria. Although the problems are fundamental in nature, the answers might lead to innovative solutions to controlling these organisms, particularly in the food chain where their presence can cause significant economic and public health issues for mankind. All five authors contributed to researching, writing and editing this review. All authors have read and agree to the published version of the manuscript. We are grateful to colleagues in Microbiology at NUI Galway and to members of the EuroMicropH COST Action for useful discussions. This work was supported by the European Union's Horizon 2020 research and innovation programme under the [PERSON] grant agreement No.721456, by the EuroMicropH COST Action CA18113, and by a grant from the Irish Department of Agriculture, Food and the Marine (17/F/244). The authors declare no conflict of interest.
## 2 Multi-Source Information and the Bayesian Model  
In this section, various kinds of reliability information and the Bayesian method are introduced. The following reliability information can be collected for components of on-orbit satellites according to engineering experience.  
1. [label=()]
2. Field data \(D=\left\{t_{1}^{D},t_{2}^{D},\cdots,t_{r}^{D},t_{r+1}^{D},\cdots,t_{n}^{D}\right\}\) are collected during the operation of target components, where \(n\) represents the sample size, \(\left\{t_{1}^{D},t_{2}^{D},\cdots,t_{r}^{D}\right\}\) are the failure times of the field data, and \(\left\{t_{r+1}^{D},\cdots,t_{n}^{D}\right\}\) are the censored data. It should be noted that the censored data in this paper means the correct censored data.
3. Historical lifetime data \(D_{H}=\left\{t_{1}^{H},t_{2}^{H},\cdots,t_{d}^{H},t_{d+1}^{H},\cdots,t_{p}^{H}\right\}\) are data for the end of operation of the same kinds of existing products, where \(p\) represents the sample size, \(\left\{t_{1}^{H},t_{2}^{H},\cdots,t_{d}^{H}\right\}\) are the failed data, and \(\left\{t_{d+1}^{H},\cdots,t_{p}^{H}\right\}\) are the censored data.
4. Similar data \(D_{S}=\left\{t_{1}^{S},t_{2}^{S},\cdots,t_{k}^{S},t_{k+1}^{S},\cdots,t_{m}^{S}\right\}\) are the data of similar components, where \(m\) denotes the sample size, \(\left\{t_{1}^{S},t_{2}^{S},\cdots,t_{k}^{S}\right\}\) are the failed data, \(\left\{t_{k+1}^{S},\cdots,t_{m}^{S}\right\}\) are the censored data, and \(\rho\) is the inheritance factor that reflects the similarity with the target components.
5. Degradation data \(X=\left\{X_{1},X_{2},\cdots,X_{l}\right\}\) are collected from \(l\) components during the operation for a single parameter, where \(X_{d}=\left\{X_{d1},X_{d2},\cdots,X_{dh}\right\}\) (\(d=1,2,\ldots l\)) are observed at time \(d1,d2,\cdots,dh\).
6. Expert information is provided by expert experience, and usually includes two forms: (a) Point estimation \(R_{0}\) of reliability at time \(\tau_{0}\) and (b) the lower confidence limit \(R_{L}\) for the reliability at time \(\tau_{0}\) with confidence level \(100(1-\gamma)\%\).  
There are four major steps to the Bayesian method proposed in this paper: (i) Prior distributions are determined by historical lifetime data, degradation data, similar data, and expert information,which are denoted by \(\pi_{i}(\lambda,\beta)\) (\(i=1,2,3,4\)); (ii) Corresponding posterior distributions \(\pi_{i}(\lambda,\beta|D)\) (\(i=1,2,3,4\)) are obtained by fusing the field data; (iii) Fusion weights are calculated using the ML-II method, and the joint posterior distribution \(\pi(\lambda,\beta|D)\) can be obtained; and (iv) Residual life can be estimated.
## Materials and Methods
### Estimation of the Minimal Biofilm Eradication Concentration of Oral Antiseptics Against Bacteria  
A total of 100 \(\upmu\)L of _S. aureus_, _P. aeruginosa_, _E. faecalis_, or _C. albicans_ suspension (10\({}^{5}\) cfu/mL) in tryptic soy broth (TSB) medium was introduced to each well and incubated at 37 \({}^{\circ}\)C in 5% CO\({}_{2}\) for 24 h without shaking. For _Str. mutans_ and _A. actinomycetemontants_, conditions for culturing were analogous with the exception that TSB supplemented with 3% sucrose was applied. Next, 100 \(\mu\)L of medium was removed, leaving biofilm-forming organisms attached to the bottom of a 96-well plate. Subsequently, geometric dilutions of oral antiseptic (OAs) in medium were applied to the wells and left for another 24 h at 37 \({}^{\circ}\)C in 5% CO\({}_{2}\). The culture with no added antiseptic served as a positive control for microorganism growth, while the well containing the sterile medium only served as a sterility control for the experiment. After incubation, 5 \(\mu\)L of triphenyl tetrazolium chloride (TTC, Sigma Aldrich, TaufRichern, Germany) was added to each well and incubated for 5 h at 37 \({}^{\circ}\)C. A change of colorless TTC to red formazan confirmed the presence of metabolically active microorganisms. The antiseptic concentration in the first colorless well, neighboring the red well, was taken as the minimal biofilm eradication concentration (MBEC) value. Because thick cell walls of _C. albicans_ may impede the penetration of TTC and _E. faecalis_ may not always metabolize TTC due to its specific metabolism pathways, an additional evaluation of cell viability for these species was performed; for example, the biofilms in plate wells were agitated using an automated pipette, removed from 96-well plates, and spotted on a stable Sabouraud or Mueller-Hinton (M-H) agar plate (Biomaxima, Warsaw, Poland) for _C. albicans_ and _E. faecalis_, respectively and incubated for 48 h. The presence of living colonies on agar indicated the lack of MBEC, while the absence of colonies in the place where spotting was performed confirmed that the particular concentration of oral antiseptic can be considered the MBEC. For the purpose of clarity, results are presented as the percentage of dilution of a specific oral antiseptic product, wherein the original oral antiseptic product was considered to be 100%. These experiments were performed using six repeats.
# Integrating IP Mobility Management Protocols and MANET: A Survey
## 4 IP Mobility Management in MANET and Comparative Summary
### Reactive Gateway Discovery-Based Mobility Management Solutions
It introduces four metrics to determine the congestion: The contention metric, which is measured through the link layer using request to send (RTS) and clear to send (CTS); the queue metric at any given node along a path; the self-metric, which is calculated based on the contention metric and queue metric; and a final metric to measure congestion along the path. The overall tree-based structure of the network is built (parent-child relationship) upon the final metric, where a mobile node gets its hierarchical position based on the least congested path. The use of a root gateway to all MANET nodes will decrease the performance of the gateway, however, which becomes a bottleneck for the whole integrated network. Moreover, the proposed solution does not support soft state routing between adjacent nodes, where neighboring nodes must contact each other through the hierarchical structure. _Integration of mobile ad hoc networks and the internet using mobile gateways_[53] proposed a mobile gateway-based three-layer approach that uses DSDV and Mobile IP to integrate MANET and the internet. The first layer includes the Mobile IP foreign agents; the second layer constitutes the gateway nodes and mobile nodes, which are one hop distance from the gateways; and the third layer includes the normal MANET nodes. The second layer is in the middle of the other two layers and runs both Mobile IP and DSDV. For normal MANET nodes, access transparency to the foreign agents is provided through gateways where they take the responsibility of choosing the appropriate foreign agent for a MANET node. Mobile nodes are required to register with a gateway node, and  
Figure 11: Robust and flexible internet connectivity for mobile ad hoc networks [50]. gateway nodes are required to register with a foreign agent. The proposed system applies two criteria for registration; distance from the gateway for mobile nodes and distance from the foreign agent for the gateways. The second criterion is the load, which is the number of served nodes or gateways in respect to the foreign agent. The proposed system follows the reactive gateway discovery scheme, where a mobile node needs to broadcast a mobile gateway solicitation. Any gateway willing to serve would reply with a gateway advertisement. Although the system is based on a proactive MANET routing protocol, it does not utilize the exiting routing traffic. Instead, it applies the broadcasting of a gateway discovery message in addition to the DSDV traffic, which can be seen as a drawback of the system. The use of redundant registration also increases the complexity of the system where mobile nodes need to register with a gateway and gateways themselves need to register with a foreign agent.