esa-sceva/satcom-chunk-collection huggingface dataset:
## 3 Methodology
### Data Analysis and Results  
This study uses two complementary analysis techniques: Structure equation model (SEM) and fuzzy set qualitative analysis (fsQCA). The SEM is a regression-based technique [49]. It examines whether the relationships between a group of independent variables and a dependent variable are symmetric or not [15]. A symmetric relationship assumes that an increase in the degree of an independent variable will cause a corresponding increase or decrease in the values of the dependent variable. Although, research indicates that the relationships between variables are not always symmetric, they also can be asymmetric with abrupt switches occurring [50]. Thus, the fsQCA can supplement the deficiency of the SEM used to detect the asymmetric relationship between the independent variables and dependent variables [14]. The fsQCA is a set-based approache that emphasizes contextual effects and examines the effects of a combination of various causal conditions on a given outcome, thereby identifying the necessary and sufficient conditions for a high participation intention.
## 1 Introduction
### Contributions  
This paper tackles the design and validation of a BS assignment algorithm that is suitable for cellular IoT networks. BSs are expected to independently determine users' assignment solutions. We focus on cellular network scenarios, in which it is assumed that MTC and HTC devices co-exist in the same service area. The contributions of this paper are summarized, as follows:  
* We propose a distributed pricing-based BS assignment approach based on a supply and demand scheme. The solution is independently executed in each BS following a bidding process that iteratively allocates resources to users willing to pay more for the available network resources.
* The core component of our proposal is a dynamic pricing update scheme that is based on a weighted utility function that involves users' utilities and network load conditions.
* The proposed solution achieves good performance in terms of an available number of BS assignments, even in backhaul limited network scenarios, while also complying the data rate requirements of both MTC and HTC devices.  
The remainder of this paper is organized as follows. In Section 2, we provide, what we consider, the most important elements to model and describe a downlink cellular system. In Section 3 we describe in detail the BS assignment problem and pose it as an optimization problem amenable to dual decomposition. In Section 4, we describe our algorithmic proposal for solving the BS assignment problem In Section 5, we present the experimental methodology and simulation results. Finally, in Section 6 we state some conclusions and discuss future work.
# Development of Korean Indigenous Low-Temperature-Tolerant Yeast for Enhancing the Flavor of _Yakju_
###### Abstract  
_Yakju_, a traditional fermented beverage in Korea, is prepared using various raw materials and methods, and, hence, exhibits various characteristics. Low-temperature-fermented _yakju_ can inhibit the growth of undesirable bacteria and is known for its unique flavor and refreshing taste. To increase the production of volatile aromatic compounds in _yakju_, strains with strong resistance to low temperatures and excellent production of volatile aromatic compounds were screened from indigenous fruits (grape, presrimmon, plum, aronia, wild grape) and _nuruk_ in Korea. One _Saccharomyces cerevisiae_ and three non-_Saccharomyces_ strains were finally screened, and _yakju_ was fermented at 15 \({}^{\circ}\)C through mono/co-culture. The analysis of volatile aromatic compounds showed that _5. cerevisiae_ W153 produced 1.5 times more isoamyl alcohol than the control strain and reduced the production of 2,3-butanediol by a third. Similarly, a single culture of _Pichia kudriavzevii_ N373 also produced 237.7 mg/L of ethyl acetate, whereas _Hanseniospra vineae_ G818 produced \(\sim\)11 times greater levels of 2-phenethyl acetate than the control. Alternatively, _Wickerhamomyces anomalus_ A159 produced 95.88 mg/L of ethyl hexadecanoate. During principal component analysis, we also observed that the co-culture sample exhibited characteristics of both volatile aroma compounds of the single cultured sample of each strain. Our results suggest that _yakju_ with unique properties can be prepared using various non-_Saccharomyces_ strains.  
_yakju_; low-temperature fermentation; non-_Saccharomyces_; co-culture; volatile aromatic compound
## 3 Experiments and Results
### Comparison between Different Methods  
To verify the effectiveness of this method, we chose two kinds of methods based on frequency-domain analysis and wavelet support vector machines (SVM) to compare the accuracy and efficiency [5; 17]. When the amount of data is small, the calculation load of wavelet-SVM is small. However, the amount of data also limits the accuracy of the mode. For the method based on frequency-domain analysis, a lot of time is used for the time-frequency conversion. Meanwhile, the recognition result is not ideal, especially when the observation frequency of the signal is close. After 30 groups of repeated experiments with four kinds of data, the comparison results of the experiments are shown in Tables 3-5. Table 3 shows the average accuracy of three methods for the 30 groups of experiments with four different events. When the SNR was low, the noise identification was the most error-prone. Under the condition of a small sample, the recognition rate of walking based on SVM was slightly lower than the average level. The reason for this was that the characteristics of a walking target are less prominent. The recognition rate of knocking based on time-frequency analysis obtained the lowest result, which may have been interfered with by the other similar frequency factors.  
\begin{table}
\begin{tabular}{l c c c c} \hline \hline
**Method** & **Knocking** & **Walking** & **Manual Mining** & **Noise** \\ \hline AMNBP with & & & & \\ CEEMDAN-KL & 4.5693 & 4.5693 & 4.5693 & 4.5697 \\ SVM based on wavelet & 5.714 & 5.7141 & 5.714 & 5.7139 \\ Frequency-domain analysis & 6.8603 & 6.8605 & 6.8609 & 6.8607 \\ \hline \hline \end{tabular}
\end{table}
Table 4: The efficiency results of four types of events (in seconds).  
Figure 10: The contrast AMNBP results of four types of signals: (**a**) Knocking and noise, (**b**) Walking and Noise, (**c**) Manual mining and noise, and (**d**) Four types of signals.  
\begin{table}
\begin{tabular}{l c c c c} \hline \hline
**Method** & **Knocking** & **Walking** & **Manual Mining** & **Noise** \\ \hline AMNBP with & & & & \\ CEEMDAN-KL & & & & \\ SVM based on wavelet & & & & \\ Frequency-domain analysis & 85.97\% & 89.10\% & 89.63\% & 84.26\% \\ \hline \hline \end{tabular}
\end{table}
Table 3: The recognition results of four types of events. SVM: Support vector machine.  
According to the time statistics of the above three methods in the experiment, the average efficiency results of the 30 groups of experiments are shown in Table 4.  
To facilitate the comparison of the characteristics of the three methods, four events were weighted equally to produce an average. The average results are shown in Table 5. It can be seen from Table 5 that the accuracy of the method proposed in this paper was significantly higher than the other two methods, and the calculation time was much lower with the same data sets.
# Advancing the Solar Radiation Pressure Model for BeiDou-3 IGSO Satellites
## 3 Results
### BeilDou-3 IGSO Optical Properties Estimates  
In this section, the adjusted optical parameters of BeilDou-3 IGSOs are discussed. Satellite C39 is selected as an example for BeilDou-3 IGSOs. Figure 3 illustrates the estimated optical coefficients for satellite C39 without and with considering communication payloads as a function of \(\beta\) -angle. To make the presentation of Figure 3 more concise, the absorption plus diffuse reflection \((\alpha+\delta)\), as well as the specular reflection \((\rho)\) parameters, are denoted by the words \"AD\" and \"R\", respectively. It can be clearly seen that the stability of optical parameters is improved significantly when the contribution of communication payloads on \(\pm X\) surfaces to SRP perturbations is taken into account. This is closer to the fact that the satellite optical properties do not change from day to day. In the study, the adjusted optical coefficients for satellite bus with communication payloads are involved in the a priori box-wing model (Equation (3)) to enhance the ECOM1 model. The optical coefficient estimates for solar panels are not used because the contribution of solar panels can be well covered through the \(D_{0}\) term of empirical SRP models. Table 3 gives the adjusted box-wing optical coefficients for the BeilDou-3 IGSOs' satellite bus, which are acquired by averaging the daily corresponding estimates for all BeilDou-3 IGSOs during the experiment period.  
Figure 3: Estimated optical coefficient of the box-wing model for satellite C39 without (**top**) and with (**bottom**) considering communication payloads. The words “AD” and “R” represent the absorption plus diffuse reflection \((\alpha+\delta)\) as well as the specular reflection \((\rho)\) for illuminated surfaces, respectively.
## 3 Results and Analysis
### Analysis of System Energy Absorption  
For a NEAS, the total energy absorbed was composed of stored interfacial energy and frictional dissipative energy [23]. Figure 10 shows the variation trend of total energy absorbed of NEASs at different temperatures. As can be seen from the figures, the total energy absorbed by the system decreases with the increase in temperature. Because the neutral and defection-free nanotubes were relatively \"smooth\" to the flow of water molecules, the friction resistance of the molecular flow was small [7]. The total energy absorbed by the system mainly depended on the interfacial energy stored during the infiltration process. The amount of stored interfacial energy was determined on the critical infiltration pressure and the pore volume of the system. As the pore volume of different CNTs was set to be constant in model construction, the amount of stored interfacial energy mainly depended on the critical infiltration pressure.  
For DNEAS, the total energy absorbed by large (Figure 10a) or small (Figure 10b) tubes were independent to each other. Thus, the energy absorbed by DNEAS was the superposition of the corresponding single tube NEASs. For SNEAS, the total energy absorbed by the bottom tube was constant and independent to the changing of top tube size (Figure 10c). The critical infiltration pressure decreased with the increase in pore size, which was more obvious under lower system temperature [65]. The total energy absorbed by the top tube decreased with the increase in the bottom tube size. The lower the system temperature, the more obvious the decrease trend.  
Figure 9: The relationship between the number of hydrogen bonds and system temperature.
# Mathematical Modeling and Simulation of Logistic Growth
## 3 Materials and Methods
### Comparison with the Gillespie Algorithm  
In order to assess the statistical significance of the iteration mean \(\mu(N_{i})\) values obtained by our simulation, we evaluated how the same information, produced by the application of the Gillespie algorithm (exact method) [6] 1000 times, would compare to the continuous model and the corresponding raw residuals. One of the main differences between the proposed simulation and the state-of-the-art implementation of the Gillespie algorithm for logistic growth [18] resides in the interpretation of time: by taking finite unit steps in time (mirroring the discrete logistic master equation), we dictated that both reproduction and death may occur in the same step, updating the probability. However, these steps are not always synchronous. Birth (by reproduction) and death can be considered Poisson processes, meaning that the waiting time (\(\tau\)) until either process occurs is exponentially distributed [19; 20]. The underlying continuous-time Markov process has the following events and transition rates:  
* Birth, \(N\to N+1\), with rate \(\gamma=rN\) accounting for the left-hand side of the subtraction within the logistic equation \(\frac{dN}{dt}=rN\Big{(}1-\frac{N}{L}\Big{)}\).
* Death, \(N\to N-1\), with rate \(\omega N=\frac{rN^{2}}{L}\), corresponding to the right-hand side, \(\frac{dN}{dt}=rN\Big{(}1-\frac{N}{L}\Big{)}\). This rate is dynamic, depending on the current value of \(N\).  
The corresponding transition probabilities are given as:  
* \(P(N\to N+1)=\frac{\gamma}{\gamma+\omega N}\).
* \(P(N\to N-1)=\frac{\omega N}{\gamma+\omega N}\).  
They are used for rejection sampling: if the sample drawn from the uniform distribution is smaller than \(P(N\)\(\rightarrow\)\(N+1)\), then the creature reproduces; otherwise, it dies. This makes the two events mutually exclusive [21], another major difference with respect to the proposed simulation, where they can happen at the same time, resulting in no net change. To determine how long (\(\tau\)) it would take for a birth (or death) event to occur, a random number from an exponential distribution with a mean of \(\frac{1}{\gamma+\omega N}\) is drawn (cf. theorem on Poisson arrivals). As a consequence, time points were not evenly spaced across the simulations, so we took the mean of the current \(N\) at each time point over the individual simulations and weighted each count by the length of time for which it existed [19]. In this way, we could compute the \(\mu(N_{i})\) values and analyze the distribution of raw residuals with respect to the continuous model for both the Gillespie simulation and the discrete master equation simulation that we chose to implement. In particular, we divided logistic growth into three time windows, relative to the short-term, steady-state, and long-term phases, to scrutinize the corresponding residuals' histograms and normal probability plots, adding valuable information for the comparison of the two simulation approaches: time-driven, like ours, and event-driven, as in the [PERSON] algorithm.
# Conceptual Design of an Extended Reality Exercise Game for the Elderly
## 2 Background and Related Work
### Elderly Physical Health and VR Exercise Games
They found that seniors tend to prefer the virtual gamification of existing sports (such as bowling) because it is similar to real games, users are familiar with the gameplay, and have relevant memories with family and friends [30]. Repeatedly moving the limbs and using the muscles can help slow down the deterioration of physical skills [31]. Fixed-cycle training is a non-burdening activity for frail older people, with little impact on their joints [32; 33]. However, more than half of elderly users cannot often sustain periodic exercise for more than six months and lose interest because of repeated simple training [34]. Interest and pleasure are essential factors in reinforcing any exercise [35]. Multimodal VR game exercises can meet the needs of exercise while being happy, thereby enhancing exercise motivation [36]. In addition, studies have shown that physical activities in the case of fierce competition will lead to higher levels of energy consumption [37; 38; 39]. Moreover, studies with dual tasks also provide reasons to support multi-modal VR exercise games. [PERSON] et al. pointed out that physical activity could have a positive effect on cognitive performance [40]. Exercise and cognitive training, either simultaneously or sequentially, were more effective in promoting cognitive function than a single modality of physical or cognitive training [41]. Rather than separate physical and cognitive training, the combination of the two may have a more significant impact on cognition [40]. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Ref.** & **Classify** & **Activities** & **Tasks** & **Targeting Parts** \\ \hline
[34] & Physical & Cycling & Cycling & Lower body \\ \hline \multirow{6}{*}{[42]} & Physical & Cycling & Cycling & Lower body \\  & & & Orientation & Reality orientation \\  & & & Finding a bus stop & Visuospatial function \\  & & & & and attention \\  & & & & Problem-solving and \\  & & & Reporting lost items & visuospatial function \\  & & & Finding a supermarket & Visuospatial function \\  & & & Grocery shopping & Memory and attention \\  & & & Finding a travel hotspot & Visuospatial function \\  & & & Bird watching & Attention and memory \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Activities and game tasks in VR exercise games for the elderly.
# Optimization Design Study of Pipe Curtain Freezing Scheme for Sanya Estuary Submarine Channel
## 4 Analysis of the Results of the Numerical Simulation of the Original Scheme
### Evolution of the Freezing Curtain Under Seepage Conditions  
To investigate the temporal variation in the thickness of the frozen curtain, a section at Z = 10 m was selected and analyzed. Figure 7 illustrates the evolution of \(-\)1 \({}^{\circ}\)C and \(-\)10 \({}^{\circ}\)C isotherms over time for this section. Initially, at 1 day of freezing, the \(-\)1 \({}^{\circ}\)C and \(-\)10 \({}^{\circ}\)C isotherms were confined to the vicinity of the freezing pipe, with groundwater flowing normally through the entire area surrounded by the pipe screen. By the 5 th day of freezing, as the \(-\)1 \({}^{\circ}\)C and \(-\)10 \({}^{\circ}\)C isotherms started to expand, groundwater flow through the freezing zone began to decrease, with a corresponding reduction in flow rate. The \(-\)1 \({}^{\circ}\)C isotherm in the strong freezing zone completed its inter-circle first due to the higher density of freezing pipes in that area, indicating better freezing effectiveness. By the 11 th day of freezing, the \(-\)1 \({}^{\circ}\)C isotherm had completed its intersection circle, at which point groundwater ceased to flow inside the permafrost curtain, and flow began to circumnavigate the \(-\)1 \({}^{\circ}\)C permafrost curtain. At this stage, the \(-\)10 \({}^{\circ}\)C isotherm completely filled the space between the pipe curtain's steel pipes, with the outer circle of the \(-\)10 \({}^{\circ}\)C isotherm completing its cross-circle. By 14 days of freezing, the \(-\)10 \({}^{\circ}\)C isotherm had also completed its cross-circle, while the \(-\)1 \({}^{\circ}\)C isotherm continued to expand outward, with no groundwater flowing inside. The freezing process continued until the 40 th day. The thickness of both the \(-\)1 \({}^{\circ}\)C and \(-\)10 \({}^{\circ}\)C permafrost curtains increased as the temperature continued to drop. Ultimately, the thickness of the \(-\)10 \({}^{\circ}\)C permafrost curtain was measured at 5.22 m, significantly surpassing the pre-established standard and meeting the excavation requirements.  
Figure 6: Contour of the development of the frozen temperature field.
## 1 Introduction  
Conventional single-needle electrospinningning has been commonly studied as it is an easy method for manufacturing nanofibers [1]. Nanofibers that are produced by using electrospinningning have diameter and morphology that depend on many factors, including the dissolution, dispersion, viscosity, and surface tension of polymers, the volatility and electrical conductivity of the solvents, electrospinning voltage, collection distance, and ambient temperature and humidity [2; 3; 4; 5; 6; 7]. However, single-needle electrospinning has a production yield of 0.01-0.1 g/hr, which falls behind the requirement of mass production. In recent years, needleless electrospinningning has been developed, and has a higher spinning efficiency than multi-needle electrospinningning [8; 9; 10; 11; 12]. Needleless electrospinning does not clog and thus has potential for a greater yield [13; 14; 15; 16; 17; 18; 19; 20; 21; 22; 23; 24; 25; 26; 27; 28].  
Nanofibers are defined as fibers that have a diameter of less than 100 nm. They have a high porosity and a high specific surface, and are thus commonly used in many applications, including wound dressings [29; 30], release control [31], tissue engineering scaffolds [32], filtrations in environmental applications [33], metal ion adsorption [34], battery separator [35], and bio-sensors [36]. In particular, the application of wound dressings involves a complicated process of wound healing where the cell extracellular matrix components and growth factors interact. The open wounds surface is often infected with microbes, including bacteria, funguses, and viruses. An infection of a wound is initiated by the adherements of bacteria to the surface of wounds, antibiotics, antimicrobial agents, and metallic particles are incorporated with the dressings. Therefore, antibacterial agents, such as chitosan [37], silver nanoparticles [38], or zinc oxide (ZnO) [39], have been added to electrospun nanofibers, thus increasing their potential in biomedical engineering applications.  
There has been little research on the application of needleless electrospinning, and this study thus combines zinc citrate and polyvinyl alcohol (PVA) in order to form a PVA mixture for electrospinning nanofibers. This manufacturing method confirms the feasibility of the combination of other materials and needleless electrospinning technique, and also produces antibacterial nanofiber mats in a great volume. Stainless steel wires are twisted and serve as the wire electrodes for the production of PVA/zinc citrate nanofiber mats. The properties of polymer solutions, and morphology and diameter size of the nanofibers are examined, after which the antibacterial properties, cell attachment, and MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolzolium bromide) assay of nanofibers are studied.
# Finger-Gesture Recognition for Visible Light Communication Systems Using Machine Learning
## 4 System Implementation  
### Design Approach  
Two design approaches were considered for the gesture sensing operation. Approach (i): the mark-space waveform generated by all fingers is encoded. As a finger cuts the light beam, it results in a space period where the received light intensity on the PD sensor is low. In the period where light can pass between the fingers, the received intensity is high. Approach (ii): the PD output is summed over the duration of the whole gesture. The total light incident on the PD from the first to last finger cutting the light beam is recorded. The first approach was selected after an initial study showed it was more reliable, and in particular, is less dependent on the hand-speed. A minimum and maximum threshold is set, and the on-off signal is passed to the LSTM algorithm.