esa-sceva/satcom-chunk-collection huggingface dataset:
# Research on the Auto-Exposure Method of an Aerial TDI Camera Based on Scene Prediction
## 4 Test Results and Analysis
### Test Results  
In the flight test, the camera used the default integral stages N of eight to capture images of the target at 6 km with a velocity-height ratio of 0.01. As shown in Figure 8, the gray value of the image was low, the image hierarchy was not clear, and the gray histogram of the image was not uniform. After the auto-exposure function was enabled, the same target was shot again, and we could see that the gray value of the image increased a lot, the layers were clear, and the gray histogram of the image was relatively uniform.  
As can be seen from Figure 8, the number of bright spots in power spectrum Figure 8(b2) after auto-exposure is significantly increased compared with Figure 8(b1), and the three-dimensional power spectrum Figure 8(c2) is more complex than Figure 8(c1); this indicates that there are more details in the image. Meanwhile, compared to the histogram d1, the gray value of the histogram Figure 8(d2) after auto-exposure almost covers the whole gray level range, and the distribution is uniform.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Test Conditions** & **Parameter** & **Symbol** & **Value** \\ \hline \multirow{4}{*}{Camera parameters} & Focal length & \(f\) & 300 mm \\  & F number & F & 6 \\  & Transmittance of the optical system & \(\tau\) & 0.816 \\  & Size of the CCD pixel & \(b\) & 8.75 \(\upmu\)m \\ \hline \multirow{4}{*}{Flight parameters} & Velocity–height ratio & \(\eta\) & 0.01 1/s \\  & Flight altitude & \(H\) & 6 km \\ \cline{1-1}  & Horizontal visibility & \(P\) & 10 km \\ \cline{1-1}  & Ground scene reflectivity & \(\rho_{A}\) & 0.15 \\ \cline{1-1}  & Solar irradiance & \(E_{S}\) & 1000 lx \\ \hline \hline \end{tabular}
\end{table}
Table 1: Test conditions.  
Figure 7: Composition block diagram of imaging system.  
From the objective evaluation data in Table 2, it can be seen that the image information entropy and power spectrum variance after auto-exposure are significantly increased, and this indicates that the auto-exposure effect is good and the expected design purpose is achieved.
# Assessing and Priorities Delay Factors of Prefabricated Concrete Building Projects in China
###### Abstract  
Prefabricated construction has been widely accepted as an alternative to conventional cast-in-situ construction, given its improved performance. However, prefabricated concrete building projects frequently encounter significant delays. It is, therefore, crucial to identify key factors affecting schedule and explore strategies to minimise the schedule delays for prefabricated concrete building projects. This paper adopts the decision-making trial and evaluation laboratory (DEMATEL) model and analytic network process (ANP) method to quantify the cause-and-effect relationships and prioritise the key delay factors in terms of their importance in the Chinese construction industry. The DEMATEL model evaluates the extent to which each factor impacts other factors. The quantified extents are then converted into a prioritisation matrix through ANP. The delay factors of prefabricated construction projects are selected and categorised based on a literature review and an expert interview. Questionnaire are then implemented to collect the data. The results reveal that the issue of inefficient structural connections for prefabricated components is found to be the most significant factor and most easily affected by other delay factors. This research also suggests prioritising major delay factors, such as 'lack of communication among participants' and 'low productivity', in the Chinese construction industry during scheduling control. Overall, this research contributes an assessment framework for decision making in the scheduling management of prefabricated construction.  
Keywords:construction delay; prefabricated construction; decision-making trial and evaluation laboratory (DEMATEL); analytic network process (ANP); multi-criteria decision making +
Footnote †: journal: Applied Sciences
## 5 What Have We Learned?  
The development of technologies for exposure assessment and dosimetry comes hand in hand with scientific developments in bioelectromagnetics. Figure 1 (compiled from a database of publications at EMF-portal.org) compares the number of papers published per year on technical issues including dosimetry and exposure assessment, with experimental and epidemiology studies related to RF exposure of some sort. In recent years, approximately 120-140 experimental studies, 40 dosimetry/exposure assessment studies, and 20 epidemiology studies have been published per year, making radiofrequency energy one of the best-studied physical agents with respect to occupational or environmental exposures. Technical advances in dosimetry/exposure assessment have contributed immensely to the success of this field.  
In brief, we have learned a great deal since the days of the Tri-Services Program. Major technical advances in exposure assessment and dosimetry include:  
Computer programs and associated libraries of tissue electrical and thermal properties are available off-the-shelf that allow high-spatial resolution calculations of absorbed RF energy in the body and modeling of the resulting temperature increase.  
Libraries of image-based models of human and animal bodies are available from commercial sources (e.g., IT'S Virtual Family series of human models) or custom-built by individual investigators. These enable detailed dosimetric studies on individuals of different gender, age, and race.  
High-quality instruments are commercially available for RF exposure assessment. At the high end are spectrum-analyzer based instruments that provide frequency-selective measurements. These enable the user to identify particular sources of exposure and apply frequency-dependent exposure limits. Unfortunately, such equipment is quite expensive and requires specialized expertise to operate properly, particularly for low duty cycle pulsed fields. Broadband RF survey meters are much less expensive and easier to operate.  
Personal RF exposimeters are available (e.g., ExpoM-RF (Fields at Work, Zurich) and EmeSpy 200 (Microwave Vision Group, Paris)). These record RF fields in multiple frequency bands and can store exposure data over extended time periods [30], and are useful for epidemiology studies, to provide approximate records of exposure.
## 3 The Time Source Techniques
### Pulsar Star
#### 3.3.5 Application  
By the time of writing this paper, no known literature shows any application of a pulsar clock in the electrical grid or other industry sectors. But there are some lab experiments and a real pulsar clock for research.  
The world's first pulsar clock was installed in St. Catherine's Church, Poland, in 2011. It was the first clock to measure time using a signal source beyond the solar system and the second type of clock to use a signal source outside Earth. The roof of the church houses a panel with 16 antennas that receive signals from six pulsars, with the pulsar signals processed digitally using an FPGA device.  
Reference [63] designed a pulsar-based timing instrument (PBTI), which uses 3 h MSP J173+0747 data recorded from the radio telescope, NRAO20. The generated PPS signal can be directly utilized for monitoring local power system devices. It also discusses potential applications of PBTI, including accurate sampling interval control, back up of GPS, and a power system controller.  
Reference [66] introduces a pulsar-calibrated timing source to serve as the alternative timing solution when the GPS signal is unreliable. By estimating the actual frequency of the crystal oscillator used in the pulsar sampling equipment, a precise timing signal can be generated.  
Reference [68] analyzes the possibility of deploying a 20 m radio telescope within an electrical substation to receive pulsar signal.  
A hardware and software framework is developed in reference [69] to facilitate real-time high-density pulsar data transmission and processing, which can promote the application of pulsars in grid synchronization.  
In general, with microsecond-level timing accuracy, pulsar timing can be applied to Digital Fault Recorders, event recorders, protective relays, lightning correlation, and other applications.
# Multi-Channel Expression Recognition Network Based on Channel Weighting
## 2 Materials and Methods
### Attention Module--ASA  
The changes in facial expression information are often very subtle and the distinction between some expression categories is not high. At the same time, the facial features between people will also affect the accuracy of expression recognition. Therefore, this paper fuses the attention mechanism ASA to capture key facial information, as shown in Figure 7.  
Figure 6: Channel weight diagram.  
Figure 7: Attention module (ASA) structure diagram.  
The ASA module is a fusion modification of the attention mechanism of CBAM [26]. The modification of the ASA module in this paper is only for the spatial attention part, and the channel attention part remains unchanged. Specifically, in the input part, compared with the original module, the ASA module first adds a \(3\times 3\) convolutional layer; secondly, after the maximum pooling and average pooling, the channel weighting idea, ACW, is incorporated, and then enters the next convolutional layer.  
The \(3\times 3\) convolution layer is first added to the original spatial attention module, because the \(3\times 3\) convolution has a high degree of non-linearity and can represent more complex functions. After combining with the channel weighting idea, it can have better performance.
# 2D Ultrasonic Antenna System for Imaging in Liquid Sodium
## 3 Simulation Study for Antenna Parameter Optimization
### Required Beam Features and Associated Influencing Parameters  
The first requirements deal with the dimensions of the field of vision. In the orthogonal plane of each antenna, an almost constant beam's amplitude is required at each depth. In the direction of the focusing plane of each antenna, the potential grating lobes should be avoided. For depth, the amplitude should not decrease too quickly as long-distance imaging is contemplated. Other requirements concern the focal spot of the cigar-beam (axial and longitudinal resolutions).  
The antenna parameters impacting these beam features are the classical phased array parameters such as the element size in the focusing plane, the gap between two adjacent elements, and the number of elements (these three parameters define the probe total aperture in the focusing plane) and also the antenna element's curvature and aperture in the orthogonal plane.  
The effects of all these parameters in various combinations were evaluated and optimized with the CIVA software in relation to both the signal centre frequency fixed between 1 MHz and 2 MHz according to previous propagation studies in liquid sodium and to the bandwidth imposed by manufacturing constraints (about 30%). Some results of the CIVA study are presented in the next paragraph.
## 2 Description of the Problem
### Cost of the MHPP  
The minimization of the cost of the plant is considered as the objective of the optimization problem addressed in this work, and thus an appropriate model is required to be formulated. First, as the generation equipment is sized for a range around the objective power generation level, the penstock layout is the main variable in the optimization problem, which includes not only the cost of the pipe itself, \(C_{p}\), but also the costs of the labor involved in its deployment, \(C_{cur}\), associated with the required excavation and supports.  
For the cost of the pipe, the following polynomial expression is proposed:  
\[C_{p}=L_{p}\sum_{i=0}^{m}a_{i}D_{p}^{i}, \tag{13}\]  
where \(a_{i}\) and \(b_{i}\) are experimentally adjusted coefficients to be fitted to the costs of the local manufacturers. The costs of the civil works can now be evaluated as the sum of those related to the supports, \(C_{sup}\), and those related to the excavations, \(C_{exc}\):  
\[C_{cur}=C_{sup}+C_{exc} \tag{14}\]To calculate these two costs, the height difference between the terrain and the penstock is required to be evaluated. This variable will be denoted with \(\epsilon(s)\), which is written in terms of the arc-length variable \(s\), shown in Figure 3:  
\[\epsilon(s)=S_{z}(s)-f(S_{x}(s),S_{y}(s)) \tag{15}\]  
This gap (shaded in Figure 4) can reach positive and negative values along the path of the penstock, having different implications: positive gaps (the penstock lies over the terrain surface) results in the need for supports, while negative ones (the penstock lies under the terrain surface) result in the need for excavations. Now, both \(C_{sup}\) and \(C_{exc}\) can be calculated. The first is calculated through the integration along the path of the cost of a single support (that depends on its height) times the linear density of supports \(\mu_{sup}\). The cost of a single support has been defined by a constant \(k_{sup}\) times its squared height. This expression has been proposed to fit the average costs following the local technicians indications. On the other hand, the excavation cost is calculated as a unitary volumetric cost, \(k_{exc}\), multiplied by the total volume to be excavated, which is determined by integrating along the path a certain digging cross-section, defined by a cut angle \(\beta_{exc}\). These approximations result in the following expressions:  
\[C_{sup}(s) = \left\{\begin{array}{ll}\mu_{sup}\int_{\Gamma(s)}k_{sup}\epsilon _{sup}^{2}ds&\text{where }\epsilon\geq 0\\ 0&\text{otherwise}\end{array}\right. \tag{16}\] \[C_{exc}(s) = \left\{\begin{array}{ll}k_{exc}\int_{\Gamma(s)}(tan(\beta_{exc })\epsilon_{exc}^{2}-D_{p}\epsilon_{exc})ds&\text{where }\epsilon<0\\ 0&\text{otherwise}\end{array}\right. \tag{17}\]  
The scheme of these two models is shown in Figure 6 for a clearer understanding. Note that the extra distance \(\epsilon_{0}\) to be nailed to the ground has been considered proportional to \(\epsilon\), and thus can be grouped in constant \(k_{exc}\).
## 2 Results and Discussion
Glycosides act as a key component for improving various pharmacological actions, such as anticancer, antifungal, and antitumor activities [29]. Figure 4: The growth inhibitory effect of ginensosides Rh2, F12, CK, and CKGal on cancer cells. **(a)** B16F10 (skin cancer), **(b)** AGS ( gastric cancer), **(c)** HeLa (vertical cancer), and **(d)** U87 MG (brain cancer). The cells were treated with increasing concentrations of compounds (6.25, 12.5, 25, 50, 100 and 200 \(\upmu\)mol) for 72 h and cell growth was measured by MTT assay. The potential molecular mechanism of CKGal has yet to be explored. However, components of ginseng have been found to induce cell cycle arrest in the G1 phase by upregulating the expression of p21 [6]. Extracts from ginseng have been found to inhibit cancer cell growth, both through suppression of the MAPKs pathway [30] and through activation of MAPKs [31]. Ethanol extract of ginseng was found to downregulate the expression of proliferating cell nuclear antigens (PCNAs) in vivo, and the activated form of Stat-3 in vitro [31]. Compound K is known to upregulate the expression of p21 and activate _c_-jun N-terminal kinase (JNK) for cell cycle arrest in the G1 phase in human monocytic leukemia cells [32]. Although our research lacks study in the mechanism of action of such molecules, the potential mechanism of action of such compounds may be involved with the activities associated in the regulation of cell cycle, apoptosis, or proliferation of cells. Previous studies have shown an enhanced anticancer activity of ginseng when the sugar units are found in the C-3 or C-20 position in comparison to sugar units at the C-6 position [6]. In this study, CK and Rh2, which contain sugar in the C-20 and C-3 position, respectively, showed quite similar activity against all the cancer cells tested. The anticancer activity of both of these ginsengosides was better than that of F12. CKGal showed better anticancer activity in the case of B16F10 and AGS cancer cell lines when compared with CK. However, the activity was not improved in HeLa and U87 MG cancer cell lines. It is now an established fact that the number of sugar moieties and different substituent groups in the side chain of the dammarane saponin or aglycone protopanaxadiol affects the activity of the ginsengosides against different cancer cell lines. On the other hand, the addition of sugar moieties increases the water solubility of the compound. Hence, it may be possible that it is easier for the compound to reach the target because of the increase in its solubility. We anticipate that this preliminary study on CKGal biosynthesis and screening of cancer cell line growth inhibitory activity will be helpful for evaluating the structure-activity relationship studies against cancers with other ginsengides in the near future. \begin{table}
\begin{tabular}{c c c} \hline
**Carbon Site** & **CK (ppm)** & **CKGal (ppm)** \\ \hline  
\end{tabular}
\end{table} 
Table 1: \({}^{13}\)C-NMR of ginsengides, 20-O-[\(\beta\)-D-glucopyrananoyll]-20(S)-protopanaxadiol (CK), and 20-O-[\(\beta\)-D-lactopyranosyl]-20(S)-protopanaxadiol (CKGal) in pyridine-\(d_{5}\).
# A Critical Review of SCWG in the Context of Available Gasification Technologies for Plastic Waste
## 6 Gasification of Plastic Waste: An Overview
### Supercritical Water Gasification (SCWG)
Moreover, he used a novel in situ hydrogenation induction gasification of organic acid (formic acid) and inorganic acid (hydrochloric acid) to achieve optimal gasification. The acids act as an H donor by promoting the cracking of unsaturated hydrocarbons and polycyclic aromatic hydrocarbons. The optimal working conditions to achieve 97% of carbon conversion are: A temperature of 800 \({}^{\circ}\)C, a reaction pressure of 23 MPa, a reaction time of 60 min, a feedstock concentration of 3 wt%, and a solution of 1 wt% formic acid. In the second one [146], he carried out experiments on PET microplastics using a quartz tube reactor. The effects of operational parameters on SCWG were investigated. Again, artificial seawater was used instead of ultrapure water. The results showed that the increase in gasification temperatureand time improved gasification efficiency, but an increase in the reaction pressure had little. By working at a temperature of 800 \({}^{\circ}\)C, at a pressure of 23 MPa, and with a reaction time of 10 min, it was possible to obtain a carbon conversion of 98%. As seen from previous studies, the metal salts contained in seawater favor the gasification of plastics, therefore, SCWG can be used successfully for the removal of microplastics from the oceans. Another highly environmental problem is that related to the incorrect sorting of waste. For example, in some cities in China there is no waste sorting and plastic is thrown away with food waste. For this reason, [PERSON] et al. [147] in 2020 studied SCWG of a mixture of model food waste (cabbage, rice, chicken, and banana peel in equal quantities) and LDPE in a 4:1 mixing ratio. In this study, they also tested the effect of three food additives: NaCl, NaHCO\({}_{3}\), and Na\({}_{2}\)CO\({}_{3}\). The experiments were conducted in a batch reactor in a temperature range of 420-480 \({}^{\circ}\)C, with a residence time of 30-75 min, with a pressure of 35 MPa, and a raw material concentration of 5-15 wt%. Again, the results indicated that an increase in the reaction temperature, a longer residence time, and a lower feedstock concentration led to a syngas rich in H\({}_{2}\). Moreover, the addition of food additives which release Na\({}^{+}\) ions had a positive effect on SCWG of unsorted food waste with plastic. A summary view of the examined works is shown in Table 6. Almost all the experiments were conducted in a quartz tube reactor or in a batch reactor and the optimal operating conditions concern pressures of 23 MPa and temperatures in the range between 450-800 \({}^{\circ}\)C. The reaction time is often around 60 min.
# Carrier Phase Dual One-Way Ranging Method Based on a Frequency Hopping Signal
## 4 Performance Analysis of the FH-DOWR Model
### Design of the Simulation Scenario  
The design of the simulation scenario comes from the GPS ISLs. For intersatellite links, the radio frequency (RF) was set as \(f_{71}=23\) GHz and \(\Delta f=0.1\) GHz. The GPS orbit is shown in Figure 9a. The relative distance and velocity between Satellite-GPS-01 and other GPS satellites are given in Figure 9b. According to the simulation, the maximum distance between satellites is 52,000 km, and the minimum distance is 400 km. If a 23 GHz radio frequency is used for the ISL measurement, then the signal path loss is approximately 214 dB. We chose the EIRP of the transmitting satellite as 40 dBW and the G/T of the  
Figure 8: Carrier phase output. (**a**) The carrier phase output of the PLL. (**b**) Carrier phase extraction. (c) Polynomial Fit.  
receiving satellite as 6 dB. In addition, the PN code length was 1023, and the PN code frequency was 10.23 MHz. Therefore, the carrier-to-noise ratio (CNR) at the receiving end ranged from 57 dB-Hz to 80 dB-Hz.
## 2 Intelligent Mooring Motion Equation in the Time Domain
### Time Domain Motion Mechanics Analysis Based on Intelligent Mooring  
Since the force vector of the conventional ship mooring time domain equation includes the contribution of waves, winds, waves, currents, mooring cables and fenders, and the mooring motion equation is solved in the time domain, the nonlinear characteristics of mooring cables and fenders can be directly considered. Similarly, the complex characteristics of the influence of each unit of the intelligent mooring system on the ship's motion response can be considered in the above time-domain equation. Therefore, if the force F of the intelligent mooring system on the ship is added to Equation (1) above, the exciting force generated by the mooring system instead of the traditional cable and fender can be reflected. Then, the equation above--after considering the influence of the force generated by the intelligent mooring system device--can be expressed as:  
\[(M+m)X^{\prime\prime}(t)+\int\limits_{0}^{\infty}X^{\prime}(t)R(t-\tau)d\tau+ KX(t)=F^{(1)}+F^{(2)}+F \tag{4}\]  
\[F=\sum\limits_{q=1}^{n}F_{q} \tag{5}\]  
In the above equation, \(F\) is the mooring force exerted on the ship by the intelligent mooring system. In the active control mode of the intelligent mooring system, the external load is mainly generated by the mooring system mechanism. In actual system operation, the mooring force can be the resultant force of multiple intelligent mooring units; \(F_{q}\) is the force provided by the QTH intelligent mooring system and \(n\) is the number of mooring system units, which can be understood as the number of mooring devices.  
Figure 2: Motion and force diagram of a mooring ship.  
Therefore, if adopting an intelligent mooring system instead of cables and fenders, it is then necessary to find a suitable mooring force \(F\) to effectively inhibit the motion of the mooring ship. Obviously, the intelligent mooring system will be realized mainly through the mechanical friction in the mooring mechanism itself and the damping of the actuator.