esa-sceva/satcom-chunk-collection huggingface dataset:
# A Comprehensive Review of Acoustic Methods for Locating Underground Pipelines
## 5 Factors Affecting Acoustic Methods in Pipeline Localization
### Pipe Structure: Discontinuity and Bend  
Another factor which can greatly affect wave propagation is pipe configuration. Common pipe structures, in addition to straight single pipes, are comprised of joints, bends and discontinuity, like a change in wall thickness or pipe materials. Current acoustic methods for locating buried pipes are still in development, where few field tests have been conducted on pipe rigs containing discontinuities. This is despite the fact that the effects of discontinuity on wave propagation in pipe structure have been studied by many researchers.  
Early studies on wave propagation in a cylindrical shell with discontinuity were carried out by [PERSON] [128; 129], where discontinuity was treated as a line insert or attachment. [PERSON] [130] has investigated the effects of wall discontinuities on flexural waves in the framework of thin shell theory, where the discontinuity was considered as the finite section of pipe. However, [PERSON]'s study was limited to thin-walled shell in vacuo. To study a more common scenario, [PERSON] and [PERSON] [131] established an analytical model of a buried fluid-filled pipe, in which three types of axisymmetric pipe wall discontinuities were taken into consideration, as shown in Figure 20. The wave transmission andreflection behaviours of two axisymmetric waves, including fluid-dominated wave and shell-dominate wave, were investigated theoretically. Approaches to estimating the reflection and transmission coefficients of discontinuities were also developed [132]. The reflection behaviour of leak noise signals as they encounter discontinuities has been investigated in [133], where the effects of reflection on time delay estimation for water leak detection has been highlighted.  
In addition to pipe wall discontinuity, another common pipe structure is bend. A preliminary research [134] has been conducted on the effects of bends on the propagation of axisymmetric mode L(0,2) in pipes surrounded by vacuum by using the membrane finite element model, where the reflection behaviour and mode conversion of guided waves were studied. It was found that L(0,2) mode would convert into flexural modes when transmitted through the bend. [PERSON] et al. have studied guided waves in curved pipes [135], calculating the dispersion curves for toroidal structures [136]. Since ordinary finite element methods are demanding in computational time and memory, a semi-analytical finite element method was introduced by [PERSON] et al. [137] in calculating guided wave transmission through a pipe elbow. More recently, an analytical modelling approach has been put forward in [138]. Further study on the transmission behaviours of specific modes can be found in [139; 140].  
More detailed study regarding the effects of discontinuity or bends on the propagation of guided waves in pipes can be found in [141].
## 2 Materials and Methods
### Numerical Model
#### 2.3.3 Model Validation  
An experimental measurements campaign was conducted to validate the numerical simulation results. A 10-day experiment was performed during summertime from 5 to 10 August 2021 at the Faculty of Building Services in the city of Bucharest, Romania.  
For this, a TSC and a DSTSC were integrated on the facade of the laboratory building (Figure 4), and one DSTSC was integrated in a container. The two collectors integrated in the laboratory facades were used to characterize the thermal behavior of both collectors in outdoor conditions.  
Fans were alimented with two high-precision laboratory power supply units, ZHAOXIN. The output voltage and current were adjustable. Measuring devices and their specifications are presented in the Table 1.  
The validation of the CFD methodology proposed for all the cases regarding the TSC and DSTSC was done with a comparison between the CFD results and the experimental results presented in this section. The CFD investigation was carried out for a 3D geometry of a DSTSC identical to the DSTSC integrated in the facade of the laboratory and for the same parameters as used in the experimental study. Table 2. shows the parameters of the studied case for validation.  
For the numerical simulation case, the wind speed was not integrated; thus, we chose a moment of the day with a wind velocity near zero m/s.  
Comparisons were performed between numerical results and measured temperatures of the perforated absorber plate in three different points, \(T_{1}\), \(T_{2}\), and \(T_{3}\), as well as for the separation plate in two points, \(T_{\text{DSb}}\) and \(T_{\text{DSup}}\), and in one point situated on the rear wall of the DSTSC, \(T_{\text{back}}\), and finally at the temperatures of the outlet air, \(T_{\text{out}}\).  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Device** & **Range** & **Resolution** & **Accuracy** \\ \hline Flow meter & 10 to 850 m\({}^{3}\)/h & 1 m\({}^{3}\)/h & \(\pm\)3\% of the reading \\ Pyranometer & 0 to 1500 W/m\({}^{2}\) & 0.1 W/m\({}^{2}\) & \textless{}3\% \\ Wind Velocity Sensor & 0.5 to 50 m/s & 0.1 m/s & \(\pm\)0.5 m/s \(\pm\)3\% \\ Wind Direction Sensor & 0\({}^{\circ}\) to 360\({}^{\circ}\) & 11.25\({}^{\circ}\) & \(\pm\)5\({}^{\circ}\) \\ \hline \hline \end{tabular}
\end{table}
Table 1: Devices’ technical specifications.  
Table 3 shows the comparison between CFD and experimental data. All the temperatures were predicted with an accuracy level within 6.11%. Considering that experimental measurements carry a degree of uncertainty due to the intrinsic resolution and accuracy of each measuring device presented before, we considered that the proposed CFD methodology can be used for actual and further CFD simulations within reasonable accuracy.
## 4 Discussion  
### Changes in Sediment Deposition  
The changes in physical properties (mean grain size and magnetic susceptibility), as well as \({}^{137}\)Cs and the \({}^{210}\)Pb excess activities, were used to correlate both cores, since they did not present the same sedimentation rates with differences in the time window for both lakes (Figure 5). Although LGSP and LCSP have steep slopes on the south, east and west banks, the northern coast shows mild degradations [21; 23]. The watershed area and the characteristics of the slopes of LCSP could have facilitated the dragging of particles with a more significant accumulation process on the bottom and; therefore, a higher sedimentation rate than in Laguna Grande, evidencing this change at 48 cm for LGSP and 98 cm for LCSP.  
The main sedimentological change (i.e., coarse grain size, high MS) observed at the base of both studied cores most likely related to change in the sediment supply at the local scale. According to the reconstructed age models, this change occurred within a similar time window, i.e., 100 BC-AD 150 in both cores. The presence of sandy sedimentation and the high magnetic susceptibility values could be attributed to significant changes in the terrigenous sediment inputs to the lakes. A higher variability of continental weathering conditions and sediment input have been documented in geomorphological and pedological studies, which may indicate a more changeable climate in the late Holocene after 3000 yr B.P., marked by the fluctuations in the influence of the westerlies [75]. Besides, C/N ratio and \(\delta^{15}\)N values indicated contributions of autochthonous organic matter in both lakes [48; 49; 50; 51].  
Under those considerations, we interpreted it as a transition from an arid condition in the mid-Holocene to more humid late Holocene conditions (humidity and temperature) that could have favoured the establishment of a native arboreal forest in the watersheds approximately at 100 BC-AD 150 [8; 9; 10]. Precipitations driven by the westerly winds in the region could influence the erosion rate in the watersheds displayed at the bottom of the lakes [9]. Other events that occurred in the area were dismissed, such as sediment supplies from the Biobio river, marine transgressions, emerged marine terraces and surface uplift rates, because they did not coincide with our period identified [56; 57; 58; 76].  
Figure 5: Correlation of \({}^{210}\)Pb, \({}^{137}\)Cs, magnetic susceptibility and grain size profiles of the Laguna Grande (**a**) and Laguna Chica (**b**) de San Pedro.
## 7 Vitamin D in Cosmetics and Cosmetics
### Efficacy of Vitamin D  
Clinical trials and studies have highlighted the efficacy of vitamin D in managing various skin conditions like psoriasis, wound healing, different types of acne, and UV-induced damage [231; 232; 233]. While these findings are promising, ongoing research is essential so as to fully understand the optimal use and value of vitamin D in skincare. The treatment of psoriasis, a condition marked by thick, scalp patches caused by a rapid turnover of skin cells, is listed among the most investigated uses of vitamin D and its analogs [37; 37; 231; 235; 236; 237]. One particularly useful synthetic version of vitamin D is calcipotriene. An experiment based on the utilization of calcipotriene exhibited a vast improvement in psoriasis symptoms, especially in lowering plaque thickness and scaling [37]. These results have been validated by other similar research that highlighted the efficacy of topical vitamin D analogs, towards lowering psoriatic plaques without any recorded side effects or adverse observations [238].  
The interesting function of vitamin D in wound healing has also been evaluated in several clinical trials [30; 94; 232; 239]. Effective wound healing depends on its role in cell differentiation and proliferation. Vitamin D supplementation has been pointed out both to enhance the wound-healing rates and to shorten the acquired healing time [240]. Recent research outcomes by [PERSON] et al. [239] have demonstrated vitamin D's crucial role in maintaining skin barrier integrity and reducing the symptoms of chloasma. The findings clearly highlighted that vitamin D, whether applied topically or administrated orally, reduced the chloasma severity and enhanced the wound-healing process [239].  
Another topic receiving vast attention has been the use of vitamin D in acne treatment and, for example, in treating acne vulgaris [45; 233; 241]. Topical vitamin D formulations were observed to reduce inflammation and acne lesions; however, the effects were not as consistent as with other, already widely utilized acne therapeutic interventions [45].  
Additionally, vitamin D aids in minimizing UV ray damage and potentially slowing down the skin aging process, while considering photoprotection, vitamin D's antioxidant qualities could lessen the UV-accelerated oxidative damage [45]. According to research based on how vitamin D affects skin aging, adequate levels of vitamin D in the body may contribute to keeping one's skin supple and minimizing wrinkles' appearance, although more studies are required, so as to further validate such benefits [25; 45; 193].
# Characterization and Optimization of a Conical Corona Reactor for Seed Treatment of Rapeseed
## 2 Materials and Methods
### Discharge Characterization
#### 2.2.3 Gas Temperature  
A non-conductive fiber optic temperature sensor (TS2 and FOTOTEMP1-OEM, OPTOcon, Weidmann Technologies Deutschland GmbH, Dresden, Germany) was used to measure the gas temperature inside the reactor through the Petri dish hole (as shown in Figure 1). This GaAs-based sensor provides a voltage signal proportional to the temperature with a response time of less than 2 s. The increase in temperature was monitored using a digital oscilloscope (DPO 2024, Tektronix, OR, USA) for up to 5 min. Experimental deviation due to the positioning of the probe and to probe sensitivity (\(\pm\)0.2 \({}^{\circ}\)C) was considered to be maximum \(\pm\)0.5 \({}^{\circ}\)C.
# Optimizing the Quality of Service of Mobile Broadband Networks for a Dense Urban Environment
## 4 Results and Discussions
### Statistical Data Analysis and Visualization of Measured Data  
The statistically analyzed data from the measured values in the three locations are presented in this section. Tables 2-4 are the statistical data for UNILAG, Ikorodu, and Oniru VI, respectively. As expected, missing data influences the computational results, as seen especially in Tables 3 and 4. Therefore, all the considered metrics are analyzed in order to show their face value comparison, especially at specific locations. The percentage of missing data is also computed to ascertain the statistical viability of the computed data. A summary of the statistical data of the measurements from Oniru VI is presented in Table 5.
# Research Progress in the Construction and Application of In Vitro Vascular Models
## 2 Construction of In Vitro Vascular Models
### Construction of In Vitro Vascular Model Based on Non-Microfluidics-Based Methods
#### 2.2.2 Construction of Vascular Model In Vitro by 3D Bioprinting
In conclusion, the choice of method depends on the specific requirements of the research or application, as well as the available technologies and resources. In the process of constructing vascular models, there are significant differences in cell types between bioprinting and pre-manufactured microchannels followed by endothelial cell seeding, particularly in simulating complex structures and functions involving multiple cell types. bioprinting utilizes single or multiple cell types to build vascular models. For single-cell types such as endothelial cells, bioprinting allows precise control over cell distribution and density, thereby constructing vascular structures with consistency and standardized morphology. Additionally, bioprinting can simultaneously print multiple cell types within the same structure, such as endothelial cells, smooth muscle cells, pericytes, and astrocytes, thus enabling the simulation of complex multi-cellular vascular structures and functions [97]. The method of pre-manufactured microchannels followed by endothelial cell seeding typically employs one or two cell types to construct vascular models. For single-cell type vascular models, this method involves precise manufacturing of the predefined shapes and sizes of the microchannels, followed by seeding endothelial cells on their inner surfaces to form a single-layer cell. When constructing dual-cell type vascular models, this method allows sequential seeding of different types of cells on the inner surfaces of microchannels. For example, smooth muscle cells may be seeded before endothelial cells to simulate complex cellular tissue structures [88]. In summary, bioprinting offers significant advantages in simulating complex multi-cellular vascular structures but it may involve higher costs and technological complexity. In contrast, the method of pre-manufactured microchannels followed by endothelial cell seeding is more cost-effective and straightforward, suitable for certain specific application needs.
## 6 Future Trends and Issues
### Demand Control Ventilation (DCV)
This method is based on the need to save energy in ventilation by limiting the supply of outdoor air while maintaining the desired air quality by using air cleaning. As a result, in this study, the ventilation system's operation mode detects indoor CO\({}_{2}\) and formaldehyde (HCHO) concentrations in accordance with the IAQ standards for Korean dwellings. IAQ has recently gained prominence as a means of addressing specific occupant health and safety concerns. To overcome the multi-zone demand-controlled ventilation system's over-ventilation and under-ventilation concerns, an air balancing method was developed. Increased energy efficiency has become a primary priority for the future accomplishment of zero usage in buildings. A mechanical ventilation system, which operates on a 12-month basis, is one of the most energy-intensive systems in HVAC. This suggests that lowering the airflow rates can save a lot of energy by reducing the fan's energy consumption and heating/cooling the supplied air [28]. As a result, it is suggested to investigate a building's ventilation system's energy-saving possibilities. In [215], they proposed the integration of a two-level distributed method with an upper and lower-level control, where the upper level calculates zone mass flow rates to keep zone thermal comfort (TC) at a low cost of energy, and the bottom level strategically manages zone mass flow rates and ventilation rates to accomplish IAQ in conjunction with retaining higher levels of near-energy-saving performance. The results of certain studies have shown that the DCV technique has the potential to conserve energy, particularly in buildings with a high occupancy density [216; 217]. Figure 11: A typical view of demand control ventilation (DCV) [213].
## 2 Materials and Methods
### Determination of Total Phenol Content  
The total phenol content (TPC) of the extracts was determined using a spectrophotometric method based on the color reaction of phenols with [PERSON]'s reagent [29]. The reaction mixture was prepared by mixing 100 \(\upmu\)L of the herbal extract, 200 \(\upmu\)L [PERSON]'s reagent (undiluted), 2 mL of distilled water and 1 mL of 20% sodium carbonate solution, which was added after 3 min. The mixtures were mixed in a vortex and kept at 50 \({}^{\circ}\)C in a water bath for 25 min. The optical density of the solution (absorbance) was measured using a spectrophotometer (UV-1600 PC, VWR International, Radnor, PA, USA) at 765 nm. The measurements were carried out in duplicate, and distilled water was used in the reaction as a blank. TPC was calculated according to the gallic acid standard calibration curve (y = 0.0035x, R\({}^{2}\) = 0.9995), and the results are expressed as as mean values \(\pm\) standard deviation of g L\({}^{-1}\) of the sample (\(n\) = 2 replicates).  
\begin{table}
\begin{tabular}{c c c c} \hline
**Herbal Extract and Mixtures** & **Herbs** & **Ratios (v/v)** & **Label** \\ \hline \multirow{3}{*}{One-component extract} & _Wild thyme (WT)_ & & _WT_ \\  & _Sage (S)_ & & \(S\) \\  & _Laurel (L)_ & & \(L\) \\ \hline \multirow{8}{*}{Two-component mixtures} & _WT + S_ & 1:1 & _WTS11_ \\  & _WT + S_ & 1:3 & _WTS13_ \\  & _WT + S_ & 3:1 & _WTS31_ \\ \cline{2-4}  & _WT + L_ & 1:1 & _WTL11_ \\  & _WT + L_ & 1:3 & _WTL13_ \\ \cline{2-4}  & _WT + L_ & 3:1 & _WTL31_ \\ \cline{2-4}  & _S + L_ & 1:1 & _SL11_ \\  & _S + L_ & 1:3 & _SL13_ \\ \hline \multirow{8}{*}{Three-component mixtures} & _WT + S + L_ & 1:1:1 & _WTS111_ \\  & _WT + S + L_ & 1:2:1 & _WTSL121_ \\ \cline{1-1}  & _WT + S + L_ & 1:1:2 & _WTSL112_ \\ \cline{1-1}  & _WT + S + L_ & 1:2:2 & _WTSL122_ \\ \cline{1-1}  & _WT + S + L_ & 2:1:1 & _WTSL211_ \\ \cline{1-1}  & _WT + S + L_ & 2:2:1 & _WTSL221_ \\ \cline{1-1}  & _WT + S + L_ & 2:1:2 & _WTSL212_ \\ \hline \end{tabular}
\end{table}
Table 1: Preparation of two- and three-component herbal extract mixtures.
## 3 Results and Discussion
### Qualitative and Quantitative Analysis of Volatile Compounds
(**a**) Changes in the total amount of volatile compounds when producing strong-flavor daqu. (**b**) Changes in the types and quantities of volatile compounds in dissimilar production processes of strong-flavor daqu. A, B, C, D, E, and F represent samples from different periods, respectively. dimethyl-undecane, and 2-ethyl-furan. The certain number of aldehydes in baijiu plays an indispensable role in regulating its aroma release [21], but excessive amounts will lead to a rough and unpleasant taste. Acid compounds not only directly affect the overall flavor of baijiu, for example, the existence of excessive lactic acid will cause the body taste to be sour and astringent, but also, acid compounds are precursors to the formation of ester compounds [22]. In the maturing process of daqu, acid compounds react with alcohol compounds to form ester compounds and further regulate the overall smell and taste of the baijiu body. They play an important role in the formation of daqu and baijiu flavor. 2-Butyloctanol, methyl 2-(propanoylamino)benzoate, 7,9-dimethyl-hexadecane, 2,6,10-trimethyl-dodecane, 1-methyl-2-(3-methylpentyl)-cyclopropane, 1,3,5,7-cyclooctatetreane, decene, and dihydroaplotaxene were merely found in E, while ethyl isobutyrate, ethyl isobutyrate, ethyl isovalerate, diethyl phthalate, isobutyric acid, 2-pyrrolocarbaldehyde, 2-methyl-pyrazine, 4,6-dimethyl-pyrimidine, 2,3-dimethyl-pyrazine, trimethyl-pyrazine, 1,2-dimethyl-hydrazine, methanethiol, 2,2,4,6,6-pentamethyl-heptane, 2,2,11,11-tetramethyl-dodecane, pentadecane, 4,6-dimethyldodecane, 4-methyl-nonane, 2,3,3-trimethyl-pentane, 2,3,4-trimethyl-hexane, and (_E_)-2,3-epoxydecane are volatile compounds that could merely be detected in finished products. Through these compounds, we can also find that the volatile compounds in strong-flavor daqu have undergone tremendous changes with the prolonged production duration. The concentration of different volatile compounds also varied considerably at different stages of maturation. Ethyl acetate, ethyl butyrate, ethyl caproate, ethyl caproate, and 22 other compounds showed an increasing and then decreasing pattern of change in their concentration during the maturation of the daqu. Ethyl valerate isopentyl formate, hexyl formate, ethyl heptanoate, ethyl nonanoate, diethyl succinate, and 46 other compounds were only present in the middle stages, while ethyl isobutyrate, ethyl isovalerate, and methanethiol were only produced in the final stage. Based on the complex changes in the above compounds and their crucial flavor contributions to the existence of daqu and baijiu, it is necessary to deeply analyze the law between the changes in substances and the maturity level of daqu.