bluuebunny/crossref_metadata_2025 huggingface dataset:
The Comprehensive Detection Technology for Embankment Leakage
Authors: Cao Yu , Cheng Xinhai , Yue Mingxin , Liu Huizhou , Zhou Guanqun , Wu Xiaoping
Published: December 2023

Based on the study of geophysical characteristics of embankment leakage, this paper adopts Dual coil transient electromagnetic (Dual TEM) and parallel direct current resistivity method(PDC) to carry out comprehensive detection. Dual TEM can greatly reduce the shallow blind area of conventional transient electromagnetic and improve the resolution of induced signal, PDC method can efficiently collect signals of all electrical arrange and spontaneous potential signals, By using the cross-correlation processing technology between spontaneous potential and resistivity data. we quickly eliminate the false abnormal influence of low resistivity in embankment, it is a good application in the detection of Paihe embankment leakage in Hefei, Anhui Province in 2020.
Deep Learning for Inversion of Tipper Data of a Certain Railway Tunnel in Tibet Area
Authors: Yao Yu , Luo Bing , Zhang Zhihou , Shi Zeyu , Lu Runqi
Published: December 2023

The traditional inversion methods for tipper rely excessively on the selection of the initial model, whose global search capability is poor. Inspired by the significant approximation advantage of deep learning for nonlinear inverse problems with big data, we design a deep learning architecture called TipInv-net for the inversion of tipper. TipInv-net takes the improved U-net as the basic framework to obtain the tipper response characteristics of the abnormal body, and then, dense skip connection is applied among the nested standard convolution modules to alleviate the gradient disappearance problem and enhance feature propagation. It’s worth noting that we construct a feature pyramid of tipper response via average pooling to obtain multi-scale receptive fields, which, thus enhancing global and detail location of abnormal body. The theoretical model test indicates that the position and attitude of geological anomaly body can be distinguished via TipInv-net, even in the presence of a certain level of noise, the inversion accuracy will not be greatly affected. TipInv-net has strong generalization. Besides, after the training process of the network, we can obtain the inversion result immediately. In order to verify the effectiveness of the method in this paper, the inversion of the field tipper data of a section of a certain railway tunnel in Tibet area is carried out.
UAV Seismic Source Traveltime Tomography Technology in Steep Mountainous Areas
Authors: Zhang Jun , Qian Rongyi
Published: December 2023

Active source seismic exploration is one of the most important high-resolution methods to obtain information about underground structures in tunnel engineering, and the seismic source is the key equipment to acquire high-quality data. In steep mountainous areas with complex geological structures, surface undulation, and drastic changes, the use of traditional seismic sources with high cost can seriously affect the efficiency and accuracy of detection. In this paper, a survey experiment of tunnel engineering is carried out in Lijiang, Yunnan Province, completing a fast, high-quality seismic data acquisition through utilizing the convenient, environmentally friendly, and economical UAV (Unmanned Aerial Vehicle) seismic source as the shot and wireless node instrument as the receiver. The experiment shows that the UAV seismic source can achieve low-cost and environmentally friendly excitation of seismic waves in complex mountainous areas, making a breakthrough in seismic source equipment. We obtain a high-precision velocity model by traveltime tomography, identifying the thickness of the overburden layer in the study area, and providing an important reference for tunnel engineering.
Estimation of Groundwater in Tarim Basin from Three-dimensional Resistivity Model Constructed by Magnetotelluric Data
Authors: Li Sangsang , Xu Yixian , Yang Bo
Published: December 2023

Groundwater is an important resource of irrigation and domestic water in Tarim Basin (TB), the largest arid inland basin in China. Hydrogeologic models and hydrogeochemical analysis have provided information of groundwater flow, salinity and hydrochemical type in TB. However, there is lacking in quantitative estimation of groundwater volume due to that the underground aquifer structure is unclear. To address the problem, magnetotelluric (MT) data were collected in TB and subsurface electrical resistivity were produced by MT inversion. To estimate the porosity of aquifers by resistivity, we should determine the resistivity of groundwater which is controlled by the Total Dissolved Solids (TDS) in water. From the previously published data, TDS increases from piedmont plain to alluvial plain along groundwater flow direction in TB and other similar settings. In terms of spatial distribution of TDS and 3-D resistivity model, the effective porosity of aquifers in the study area was calculated. Finally, by taking account of the water table and thickness of Quaternary sediments collected by BGP Inc., the total groundwater volume was estimated in northern parts of TB.
Estimation of Freshwater and Salinity Interfaces in the Coastal Area of Jiangsu Province by Electrical Sounding
Authors: Xu Zhengwei , Wang Xuben , Zhang Qihua , Lu Juntao
Published: December 2023

In the coastal alluvial plain of the Yangtze River Delta, specifically the Nantong Region of Jiangsu Province, China, there is a heightened vulnerability of the groundwater aquifer area due to increased urbanization and seawater intrusion. This location, a rich ecological domain with an extended history of marine deposition, is predominantly influenced by saltwater intrusion that significantly determines the groundwater quality. It is situated on the third topographic ladder. To discern the spatial variations in the hydrogeological zonation and the fresh-saline divide, we put forth an innovative methodology that incorporates multiple forms of datasets. The findings derived are of considerable relevance to the understanding of groundwater distribution related to Quaternary geology and hydrogeology within the region of interest. Furthermore, these interpretive outcomes may be instrumental in informing and directing the management and utilization of water resources in the study area.
Three-dimensional Response Characteristics of Self-potential Field for Dam Leakage Hidden Danger
Authors: He Shangfu , Deng Juzhi , Liu Suiming , Chen Hui , Gao Jianglin , Wang Shuo , Chen Yufeng , Yu Hui , Zhang Guokun , Li Yan
Published: December 2023

In order to improve the application of self-potential field monitoring in detecting the potential reservoir dam leakage, we deduced the coupling equation of the self-potential field with water flow field and ions diffusion field, based on the formation mechanism of the self-potential field. We realized the three-dimensional numerical simulation of the self-potential field of reservoir dam by coupling finite and infinite elements by analyzing the response characteristics of the self-potential field with different water levels, different levels of danger, and different periods of typical dam leakage models. The results show that the magnitude of the self-potential field is proportional to the size of the leakage channel and the magnitude of water level difference. Thus, the distribution characteristics of the self-potential field could indicate the development period of a leakage to some extent, and the leakage location and early warning could be realized by monitoring self-potential fields.
Pronounced Changes of Multi-geophysical Parameters Associated with Maduo (M= 7.4) Earthquake
Authors: Ye Qing , Singh Ramesh P. , Wang Xiao , Tao Zhigang , Tang Lei , Yao Saisai , Ma Weiyu , Fan Ye , Fan Chunyan , Liu Gaochua , Liu Chunguo , Liu Yangyang
Published: December 2023

The China Earthquake Administration (CEA) has a large network for monitoring multiple geophysical parameters to forecast earthquake and to have early warning information about an impending earthquake. In this paper, we present the analysis of various geophysical measured and borehole parameters (resistivity, borehole strain, water level, water temperature, atmospheric temperature, etc.) within 400 km radius of the epicenter. The strain measured in the borehole show pronounced tensional and compressional changes, and the direction of the main compressive strain is found to rotate clockwise. The active compression of the whole Bayankara block is found to be affected, the resistivity near the fault began to decrease and increase in different directions. The water level observed at the Yushu water well located in the southwest from the epicenter is found to change in the opposite direction at the Huangyuan borehole located in the northeast from the epicenter. Yushu water well station is affected by the clockwise activity of the whole Bayankara block, at this water level increases from 2017 and begins to decline from August 2020. Such pronounced decline in water level far from the epicenter of the earthquake prior to the earthquake event provides an early warning of the Maduo earthquake. The decline of the water level is associated with the changes in the stress within the epicentral region, such changes could provide long-term precursory information about an impending earthquake.
Dynamic Monitoring of In-situ Chemical Oxidation for Remediation of Hydrocarbon Contamination with Electrical Resistivity Tomography
Authors: Xia Teng , Zhang Jiaming , Guo Lili , Li Shupeng , Ma Xinmin , Mao Deqiang
Published: December 2023

In situ chemical oxidation (ISCO) using persulfate, a conductive oxidant, provides a powerful signal for non-invasive geophysical techniques to characterize the remediation process of hydrocarbon contaminants. This study used ISCO for remediation in a laboratory sandbox and at an on-site contaminated site to evaluate the ability of resistivity chromatography (ERT) to monitor the process of alkali-activated persulfate remediation of hydrocarbon-contaminated soils. The experimental results show that the persulfate plume migrates mainly vertically due to density-driven flow. The relationship between resistivity and pollutant metrics further showed that pollutant depletion contributed 25.6% to the resistivity change in polluted source regions, while this contribution was less than 16% in low or non-polluted regions. In addition, field monitoring results indicate that the resistivity response is consistent with changes in water chemistry, water table, contaminant concentration and temperature. In conclusion, geophysical methods are excellent for dynamic monitoring of in situ remediation processes for hydrocarbon contamination.
Three-Dimensional Inversion Algorithm with A Footprint Computational Domain for Underground Engineering
Authors: Ou Jian , Zhou Hua , Ou Renwen , Li Jianyuan , Liu Chunming
Published: December 2023

Granite bodies pose a common geohazard in urban underground engineering. The GEM-2 system, employing small coils as transmitter and receiver (Tx-Rx), has gained widespread adoption for efficiently and non-invasively delineating low resistivity targets with 1D results in the near-surface. In this paper, we propose a 3D inversion algorithm based on the footprint-guided compact finite element method and Gauss-Newton optimization to accurately delineate the 3D structure of granite boulders. To demonstrate the effectiveness of our 3D inversion method, we conducted a GEM-2 test survey in a scenario featuring a granite boulder. The inversion results exhibit superior horizontal resolution compared to the current 1D inversion methods. The three-dimensional contour of the boulder is clearly depicted by areas of relatively high resistance, showcasing the capability of our inversion algorithm.
A Deghosting Method Based on Deep Learning
Authors: Zhao Yuetong , Li Yaxing , Jia Xiaofeng , Wu Xinming
Published: December 2023

Interference of ghost has a bad effect to marine seismic exploration, which reduces the resolution seismic data and accuracy of seismic interpretation. To solve these problems, we propose a deghosting method based on deep learning. The trial calculation of synthetic models shows that this method is more streamlined and efficient in deghosting, which has good adaptability to data with with different geological models, acquisition systems and signal-to-noise ratio, recovers the energy of the frequency band affected by the ghost notch.
A Method of Removing the Interference from Urban Railway Transit in The Geoelectric Field
Authors: Zheng Guolei , Ye Qing , Liu Jun , Du Xuebin
Published: December 2023

In recent years, with the development of urban railway transit (URT), interference in the geoelectric field (GEF) has been generated. This brings serious difficulties to the acquisition of earthquake precursors. In this study, by analyzing the spectral features of daily minute-sampling GEF data without and with interference from urban railway transit (URTI) and without one respectively, the Butterworth function was selected as a transfer function for Fourier filtering, and its cutoff frequency was set. A method of removing URTIs (RURTIs) was developed. Then, the RURTI method was used to process the NS, EW and NE GEF data to better recognize the anomaly before the Guye Ms 5.1 earthquake at Yanqing station. Compared with a polynomial-smoothing filtering method, the RURTI method has better performance in improving the signal-to-noise ratio and recognizing preearthquake anomalies. After the differences between the original GEF data and the processed data using the RURTI method were calculated, a method of recognizing the preearthquake anomaly was found.
Numerical Simulation of Wave Equation Using the Finite Difference Method with Variable Refined Grid in Complex Near-surface Condition
Authors: Zhang Zhijia , Sun Zhangqing , Han Fuxing , Wang Ruihu , Lu Jipu , Gao Zhenghui , Cen Wenpan , Liu Mingchen
Published: December 2023

The horizontal layered refined grid is adopted in the conventional finite difference method (FDM) of variable refined grid for the numerical simulation of wave equation. But, the method cannot well adapt to the characteristics of undulated topography and the variation of velocity structure in near-surface region. To solve this problem, a numerical simulation of wave equation using FDM with undulated variable refined grid is proposed in this paper. The grids are generated according to the undulated topography and the spatial distribution of velocity in the near-surface region from low-velocity to the high-velocity layer. For ensuring the accuracy while taking into account the computational efficiency, the FDM with variable coefficient in above grids is used to discretize the acoustic wave equation. The numerical evaluation and example show that the same accuracy as the method using fine grid can be obtained by the new method. However, its computational time is only 43.6% of the one spent by the fine grid. Furthermore, the new method can also stably adapt to the real complex loess plateau near-surface model in a working area of Ordos Basins.
Weighted Adjoint-state Crosshole Traveltime Tomography
Authors: Liu Liu , Li Shaojun , Shi Zhenming , Peng Ming , Wang Yao
Published: December 2023

The adjoint-state method of first arrival traveltime tomography, featured with implicit ray tracing calculation, was used to compute the gradient of the misfit function without introducing Fréchet derivatives. However, the majority of velocity gradients in the adjoint-state method focus on the high velocity area due to high raypath density. Thus, the current adjoint-state method faces challenges of imaging low velocity anomalies in the near-surface by crosshole seismic acquisition. In this paper, we proposed a weighted adjoint-state Eikonal equation-based crosshole traveltime tomography method. A preconditioning operator is provided to fix the ray path density influence. The weighted method was tested on a homogeneous model, a checkerboard model, and a reduced-scale Marmousi model. Both misfit cures and velocity logs are used to make a comparison between the weighted method and the traditional method. The results show the weighted method has better resolution, faster convergence speed, and lower final residual, which demonstrate the method can mitigate the ray path effect and reduce the inverted velocity error of low velocity anomalies.
A Simple Model Generator for Radar Sounding Applications Based on Stochastic Media Model and gprMax
Authors: Lv Chen , Hao Tong
Published: December 2023

Ground penetrating radar (GPR), or more generically called radar sounding, is an established technique for probing subsurface objects and sublayer structures. Simulating pre-constructed models and comparing with the real-world observations can contribute to retrieve the geometrical and physical properties of subsurface objects. However, most GPR simulations are limited to geometrically simple models with homogeneous physical properties of subsurface media which are generally unable to represent the real-world situations. In this paper, we develop a simple model generator by combining the stochastic media model and gprMax, an open-source software for electromagnetic simulations, to jointly generate models with geometrically random fragments, which are forward models with minimum human intervention. These easily prepared and simulated models can enrich the model training datasets which can be further utilized in machine learning for GPR retrieval algorithms.
Compact RF transmission unit for nuclear quadrupole resonance spectroscopy
Authors: Kijamnajsuk P , Sibsiri K , Luengviriya C
Published: December 2023

Nuclear quadrupole resonance (NQR) spectroscopy is a non-destructive measurement technique that enables to detect materials of interest very accurately. This technique works by sending high power electromagnetic waves with radio frequency (RF) very specific to the molecular structure to excite the sample and detecting the respond signal with the same frequency. Portable NQR detectors can be potentially developed to detect explosives with non-metallic containers in the fields. However, commercial RF high power amplifiers are large and heavy, so they are not practical for field usage. In this work, we demonstrate a compact NQR transmission part which composed of an active input signal conditioner, a class-D amplifier, and an NQR coil. The active input signal conditioner circuit will convert a single rf pulse with low amplitude (<0.5Vp) to two pulses (with 180° phase difference) and they are subsequently amplified to TTL level. In the class-D amplifier, the pre-amplified pulses are further amplified by a high voltage gate driver IC to 24V amplitude. These high voltage pulses are converted to a single 24V pulse by MOSFETs connected in a half bridge configuration. Finally, the amplified pulse is fed to the NQR coil, i.e., a low impedance LC series resonance circuit. The voltage across the coil at resonance frequency is about 1kVpp.
DeepHCC: Deep learning model for real-time count rate determination of particles in homemade cloud chamber
Authors: Srisukhawasu P , Silapasart A , Limjanon T , Madlee S , Samanrak C , Somnam T
Published: December 2023

Cosmic ray (CR) particles are high-energy particles originating from outer space that often reach the ground as alpha and proton particles, which can be studied using particle detectors. While investigating CR particles is a complex process, cloud chambers offer a simple means of detection. However, they cannot measure count rates directly. To overcome this limitation, we developed a deep learning model for real-time count rate determination of particles in a homemade cloud chamber (DeepHCC), implementing YOLOv5 pre-trained weights to use with our homemade cloud chamber. We trained DeepHCC using a total of 2,435 images from our homemade cloud chamber and other cloud chambers and found that YOLOv5m was the most suitable model for our task due to its fast and accurate detection capabilities. DeepHCC performed well in fundamental evaluations, with an overall area under the precision-recall curve of 0.8886 and an F1 score of 0.8624 while operating at 61 frames per second. We also experimented on count rate determination compared to human performance, which yielded an overall accuracy of 80.15%. Overall, DeepHCC could be used with our homemade cloud chambers to create particle detector kits with comparable performance. However, our model could not detect muons and accurately identify electrons due to an imbalanced dataset used in the training process. These reveal opportunities for future research to explore other techniques to address this problem. We also plan to compare our results with other detectors to verify reliability. The results demonstrate that our work could also be an innovative prototype for an engaging educational physics instrument.
Effect of finger pressure on blood pressure measurement using photoplethysmography
Authors: Numim P , Apiwong-Ngam N , Yarin S , Sungthong R , Choopun S
Published: December 2023

Photoplethysmography (PPG) is a technique that uses a light source by allowing light to pass through a fingertip and detect the reflection of light to obtain the PPG signal. The PPG signal can be used to monitor personal health and to determine the blood pressure (BP) value. However, it is difficult to obtain a reliable PPG signal due to various environmental factors. A pressure that a finger presses on the sensor during measurement is one of the main factor to obtain a wave-like PPG signal. In this work, effect of finger pressure on blood pressure measurement using PPG is intensively investigated in order to improve the reliability and accuracy. The BP prototype with a force sensor put at a location of fingertip next to the light sensor is developed in order to detect a finger pressure. An optimum condition of the fingertip pressure for the BP measurement is evaluated by using a maximum and minimum values of PPG signals from the IR light reflection. The calibration of the BP prototype is performed and back test with a commercial BP monitor. It is found that the optimum finger pressure is in medium region of 65-75 with the reliable wave-form. Moreover, the accuracy of our BP prototype is about ±2.0 mmHg compared to the accuracy of commercial BP monitor of ±3 mmHg and the accuracy of our previous work of ±9.2 mmHg. Thus, our developed BP prototype with the control of the finger pressure exhibits an improvement of reliability and accuracy. This suggests a potential application for a commercial BP monitor without a cuff.
Investigating the linear equations of maximum and minimum slope lines on a linear graph in high school physics experiments using numerical method
Authors: Som-Am S , Sripongpun N
Published: December 2023

This study investigates the maximum and minimum slope lines of a linear graph used in high school physics experiments. The uncertainty of the graph is calculated by considering the steepest and shallowest possible lines. However, manually drawing these lines can be challenging. Thus, this research employs numerical calculation method to determine the slopes of the two straight lines that pass through the number of error bar of y-data as much as possible. These lines are drawn between the lower edge of the error bars and the upper edge of the error bars of two data points on the graph. Two case studies are conducted using physics’ experimental data, which includes three columns; x-data, averaged y-data and standard deviation of the sampling distribution of means. The results are presented as data points with error bars on graph, along with the maximum and the minimum slope lines and their corresponding linear equations. Further analysis of uncertainties of slope and Y-intercept can be performed using these equations. These findings are valuable for researchers, educators, and students to interpret and report the results. In addition, a web application is presented to facilitate the determination, further enhancing the study’s accessibility and usefulness.
A STEM activity in design and development of a simple machine using 3D printing and GoGo board
Authors: Sriwitaya K , Tuptim P , Wattanakasiwich P
Published: December 2023

In 21st-century education, numerous research studies have shown that learner-centered teaching is significantly more effective than traditional lectures. A critical aspect of studying physics effectively is developing conceptual understanding through hands-on activities. With today’s technology easily accessible to both students and teachers, hands-on activities aimed at promoting physics understanding and design thinking have become more accessible than in the past. This research aims to create supplementary activities that utilize Makerspace tools such as 3D printers, laser cutters, and GoGo Board learning kits to enhance learning efficiency in the context of simple machines in physics. The primary goal of these activities is to help students apply their knowledge of simple machines, focusing on concepts such as mechanical advantage and machine efficiency while also developing Makerspace tool proficiency. Additionally, students will practice design thinking by creating prototypes of simple machines to accomplish specific tasks. Their tool utilization and design thinking abilities will be evaluated based on the simple machines they create, and mechanical advantage will be measured using a device capable of creating and measuring the tension in a rope designed with a GoGo Board. The process of developing these learning modules will be presented and discussed in detail.
Variations in thermospheric density during two consecutive geomagnetic storms of different solar wind conditions in November 2022
Authors: Panpiboon P , Noysena K , Yeeram T
Published: December 2023

Geomagnetic storms can cause severe space weather impacts on space technology, such as anomaly and loss of satellites and spacecraft. We investigate solar wind conditions in responsible for two consecutive geomagnetic storms driven by different sources: a high-speed solar wind stream (HSS) on November 3-4, 2022, and a coronal mass ejection (CME) associated with an M5.2 solar flare on November 7, 2022. Spatial and temporal variations in thermospheric density and auroral activity are studied for the two geomagnetic storms. Measurements from the Swarm satellite show that the HSS-driven geomagnetic storm enhanced the thermospheric density by ~69.4% at 462 km and by ~92.8% at 511 km, and the CME-driven geomagnetic storm enhanced it by ~99.4% at 462 km and by ~145% at 511 km. Images taken by the F17 DMSP/SSUSI indicate the auroral emission produced by CME-driven geomagnetic storm is significantly stronger than that produced by HSS-driven storm, while the HSS-driven auroras last longer than the CME-driven ones. The correlation between the hourly moving averaged SymH data and the thermospheric density is stronger for Swarm-A than for Swarm-B. The response times of the thermospheric density for the HSS-driven geomagnetic storm are zero at 462 km and ~47 minutes at 511 km, while for the CME-driven geomagnetic storm are ~28 minutes and ~35 minutes, respectively. This study sheds light on the mechanisms underlying the change in the thermospheric density in relation to different geomagnetic activities.
Monte Carlo Simulation and measurement of Calibration Neutron Monitor count rate dependence on proximity to water
Authors: Duangjai B , Nuntiyakul W , Seripienlert A , Pagwhan A , Chaiwongkhot K , Sáiz A , Ruffolo D , Evenson P
Published: December 2023

Due to their global availability, neutron monitors play a crucial role in measuring time variations in the Galactic cosmic ray flux. A portable calibration neutron monitor (CalMon) is useful for intercalibrating various neutron monitors to ensure accurate measurements. A common technique to ensure that the calibration is done in a consistent environment is to place the CalMon at some height above a wide container (such as a portable swimming pool) filled with water. This study investigates the impact of CalMon height and water depth on the count rate ratio relative to a standard 18NM64 count rate recorded nearby (CalMon/18NM64). We compare simulated data from the FLUKA Monte Carlo package to experimental data from [1] to demonstrate the statistical accuracy of our simulation. Using the simulation results, we then extend the study of the proximity-to-water effect on the counting rate. In this work, we present a preliminary empirical model by analyzing the CalMon/18NM64 as a function of CalMon to water distance. Overall, our study enhances understanding of the response of calibration monitors (now often called “mini-neutron monitors”) operated in various locations worldwide, and validates the Monte Carlo techniques used to model the response of the global neutron monitor network.
Solar energetic particles propagation during solar events at the beginning of the 25th solar cycle
Authors: Khumlumlert T , Mongwanna T , Chuenkam P , Khotkhanti C , Karnjanapa W , Aiemsa-Ad N , Peldon D
Published: December 2023

Space weather is induced by solar events like solar flares, solar wind, the solar cycle, and coronal mass ejections. These solar events have the potential to affect various aspects of Earth, including radio communications, electric power failures, and navigation signals, and pose risks to spacecraft and astronauts. Solar activity is more or less intense according to the solar cycle. We are currently in the 25th solar cycle, which began in 2019. This research studies the space weather at the beginning of the 25th solar cycle using the distribution data obtained from spacecraft including the explosion on the Sun’s surface, by analyzing the solar energetic particles (SEPs) propagation. The distribution of SEPs with flux; F is given by a power law for solar events on November 29, 2020, July 3, 2021, and April 22, 2022, with indices 6.2, 4.5, and 1.8 depending on energy. The propagation of the SEPs was studied using Ruffolo’s transport equation, which was solved using the Finite-differences method. We found that solar flares with higher X-ray intensity have a longer movement along the irregular magnetic field and arrive at Earth more quickly than those with lower X-ray intensity. The SEPs are weaker and have no impact on Earth, although both events generated coronal mass ejection. The M-class and X-class solar flares occurred during the beginning of the 25th solar cycle, the position of explosion and injection time of particles resulted in space weather with little impact on Earth.
Analysis of Moon shadow from 2021-2022 LHAASO WCDA Data
Authors: Maburee J , Mitthumsiri W , Nuntiyakul W , Pattarakijwanich P , Ruffolo D , Sáiz A , Seripienlert A ,   LHAASO Collaboration
Published: December 2023

The Large High Altitude Air Shower Observatory (LHAASO) is a major ground-based array of cosmic-ray (CR) detectors in the Sichuan Province in China. The Water Cherenkov Detector Array (WCDA) is an essential component of LHAASO, which is designed to measure ~1-50 TeV CRs and gamma rays. As observed on Earth, the Moon blocks some CRs to create a shadow. Although CRs are mostly protons, WCDA can probabilistically identify some constituents (mostly electrons and photons) of CRs which produce electromagnetic (EM) showers in the atmosphere, using the “compactness” (C) of the showers as the criterion for which the higher C indicates the higher probability of an event being EM. The observed CR Moon shadow positions must be shifted from that of the actual Moon due to the deflection of charged particles by the Earth’s magnetic field. We analyze the LHAASO WCDA data from March 2021 to December 2022 to study the properties of the CR Moon shadows for events with C < 10 and C > 10, such as the shifted position and the size of the shadow at different energies. We found that i) CR shadows’ shifts decrease when energy increases, and ii) the higher the energy, the size of the CR shadows are more compact. This analysis is useful for detector calibration, event selection study, and understanding CR trajectories in the geomagnetic field.
Holographic RG flows from four-dimensional N = 2 gauged supergravities
Authors: Lunrasri Nutthaphat
Published: December 2023

In quantum field theories, the examination of particle interactions is facilitated through the application of Feynman diagrams. The computation of loop Feynman diagrams often yields divergent or infinite values. To tackle this issue, a method known as renormalization is employed, which entails the removal of these infinities. The phenomenon of a physical system undergoing changes under different scales gives rise to a concept referred to as the renormalization group. Certain renormalization group trajectories, denoted as RG flows, describe transformations of a conformal field theory (CFT) into other conformal or non-conformal theories. These transformations result in deformations of a UV conformal fixed point into another fixed point or into a non-conformal phase within the infrared (IR) regime. In this study, we investigate holographic RG flows originating from N = 2 gauged supergravity with an SO(2) × SO(6) gauge group. These solutions delineate RG flows from the N = 2 CFT to a three-dimensional non-conformal field theory driven by mass deformations. This transformation is elucidated through the AdS/CFT correspondence, also known as AdS/CFT holography.
Development of a solenoid magnet for emittance compensation
Authors: Jummunt S , Sunwong P , Prawanta S , Kwankasem A , Sooksrimuang V , Promdee W , Chaiyasit K , Aim-O P , Chunjarean S , Klinkhieo S
Published: December 2023

This paper explores the implementation of a solenoid field to achieve electron beam focusing and compensation of transverse emittance, which is generated from photocathode RF gun. An extensive investigation was conducted to determine the optimal solenoid magnetic field required for focusing an electron bunch with a charge of 0.5 nC. A magnetic field strength of 0.25 T was chosen for emittance compensation, enabling the reduction of emittance to below 1.20 mm-mrad at the end of linac. The engineering design of the solenoid magnet for this system is presented in detail, ensuring precise dimensional tolerances within the range of ±30 µm. To ensure its effectiveness and reliability, extensive thermal and mechanical analyses were conducted. Currently, the prototype solenoid magnet is in the fabrication process.
Exploring the Zeeman effect in spectroscopy for laser frequency manipulation in optical systems
Authors: Tanasanchai N , Siriworakoonchai P , Udommai P , Anukool W
Published: December 2023

In optical systems, acousto-optic modulators (AOMs) and electro-optic modulators (EOMs) are commonly utilized for laser frequency manipulation. However, these devices come with drawbacks such as high cost and the requirement of optical adjustments to change the frequency shift direction. In this study, we propose an alternative method that harnesses the Zeeman effect in the saturated-absorption spectroscopy to shift the energy levels in atom. With this technique, the laser frequency can be shifted without the need for AOMs or EOMs. The stability of laser locking was investigated for any case of polarization of probe and pump beam. We found when the polarization of the probe and pump beams is linear and perpendicular, it results in the highest level of stability in laser locking compared to other polarization configurations.
Effect of laser detuning and Rabi frequency on rubidium Rydberg electromagnetically-induced transparency for atom-based electric field sensing
Authors: Ketaiam K , Thaicharoen N
Published: December 2023

Atom-based electromagnetic field sensing is a highly precise and sensitive technique for measuring and detecting electromagnetic fields, based on the principles of the Rydberg electromagnetically induced transparency (EIT). In this study, we simulate an atom-based electric field measurement system using a four-level system of rubidium atoms. We solve the steady-state solution of the Lindblad master equation using a Hamiltonian that contains information about rubidium properties and the external electric field. We observe that the splitting of the EIT signal is directly proportional to the intensity of the applied electric field, making it a highly sensitive method for electromagnetic field sensing. In addition, we investigate the effect of laser detuning and Rabi frequency on the linewidth and signal strength of the EIT signal in order to obtain optimal parameters for future experiments. This study provides insights into optimizing the EIT signal for electromagnetic fields detection, with potential benefits for future developments in this field.
The influence of extrinsic structural factors on the dielectric properties of CaCu3Ti3.90Cr0.10O12 ceramics
Authors: Khongrattana Prachit , Mani Marina , Khongpakdee Suwit , Boonlakhorn Jakkree , Srepusharawoot Pornjuk
Published: December 2023

In this study, CaCu3Ti3.90Cr0.10O12 was produced via a solid-state reaction method. The phase formation and crystal structure analyses indicate a body-centered cubic structure with the space group Im3. There were no observed secondary phases. A microstructural study revealed that, with the sintering time fixed at 3 h, the average grain size increases as the sintering temperature was raised from 1090 °C to 1110 °C. Interestingly, the dielectric permittivity of CaCu3Ti3.90Cr0.10O12 ceramics increases from 3.53×104 to 8.04×104 as the sintering temperature was increased. In addition, the loss tangent of the CaCu3Ti3.90Cr0.10O12 ceramic decreases from 0.086 to 0.043. Impedance spectroscopy reveals the construction of an internal barrier layer capacitor structure in CaCu3Ti3.90Cr0.10O12 ceramics. The presence of Cu+ and Ti3+ in the CaCu3Ti3.90Cr0.10O12 system is shown by X-ray photoelectron spectroscopy, indicating a charge compensation mechanism produced by the oxygen vacancy within the CaCu3Ti3.90Cr0.10O12 ceramics. Interfacial polarisation may be the most significant contributor to the high dielectric permittivity of these ceramics.
Analysis of superconducting critical temperature using numerical method
Authors: Rientong Komkrit , Natkunlaphat Nattawut , Pinsook Udomsilp
Published: December 2023

Currently, many studies have shown that the critical temperature (Tc) of a superconductor can be predicted by using the BCS theory. In this work, we analyse Tc of superconductors, which is determined by the spectral function (α2F(ω)) derived from the interaction between electrons and phonons. The equation that we used for the calculation is

T

c

strong

=

f

1

f

2

T

c

weak

. In this equation,

T

c

weak

refers to the Allen-Dynes formula and f is the correction factor. We compare the Tc obtained from this equation with our method. Many important parameters are given and analysed, such as average coupling strength (λ), the square root of the average frequency square (ω2), and average logarithm frequency (ωln). We use numerical methods and expect to improve the equation to calculate Tc to be user-friendly. Normally, the calculation of Tc can be challenging and time-consuming. The most successful theory explaining the general properties of superconductors is the BCS theory. It explains the mechanism in which normal conductors become superconductors, and the pairing of electrons known as the Cooper pairing is formed by the electron-phonon interactions. In the past, the BCS theory predicted the limit of the critical temperature of superconductors to be around 30-40 kelvin. Recently, several researchers have been discovered a higher Tc value than the limited value from experiments under high pressure. Our method could provide a better analysis of appropriate Tc of superconductors to support new discoveries in the future.
The effect of cathode arc current on the structures of TiN thin films prepared by cathodic arc deposition
Authors: Honglertkongsakul Kanchaya , Choeysuppaket Attapol , Khwansungnoen Phalakorn , Rattana Tanattha
Published: December 2023

The titanium nitride (TiN) thin films were fabricated by the cathodic arc deposition technique. The effect of titanium cathode arc current on structural, chemical, and morphological properties of thin films was investigated by X-ray diffraction(XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscope (FESEM) and atomic force microscopy (AFM), respectively. The XRD results showed titanium nitride formation with a fcc phase structure for all samples and the preferred orientation changed from (111) to (200) plane with increasing the cathode arc current from 50 to 60 A. The crystallized sizes of the thin films increased as increasing the cathode arc current. In addition, the relationship between the size of the microdroplets on the coating surfaces and the arc current was examined.
Soil-to-organic Sangyod rice grain transfer factors (TF values) of natural and anthropogenic radionuclides in Phatthalung province, Thailand
Authors: Kessaratikoon P , Sungkhao R , Charoenmak P , Changkit N , Boonkrongcheep R
Published: December 2023

The specific activities of natural (40K 226Ra and 232Th) and anthropogenic (137Cs) radionuclides in paddy soil and organic Sangyod rice grain were measured and analyzed in this study with an aim to determine the soil-to-organic Sangyod rice grain transfer factors (TF values) of all required radionuclides in Don Pradu sub-district, Pak Phayun district in Phatthalung province in the south of Thailand. The high purity germanium (HPGe) detector and gamma-ray spectrometry analysis system which were installed and used in advanced laboratory at TINT were used to conduct experiments to measure and analyze of all required radionuclides in this research. The average concentrations of 40K 226Ra, 232Th, and 137Cs in paddy soil were found to have a value of 657.30 ± 23.03, 180.01 ± 4.39, 162.02 ± 3.84 and < 1.81 Bq/kg respectively while in organic Sangyod rice grain, their values were 24.11 ± 2.01, 0.28 ± 0.07, 0.17 ± 0.06 and 0.10 ± 0.03 Bq/kg respectively. For TF values were calculated and found to be 0.037, 0.002, 0.001, and 0.055 for 40K, 226Ra, 232Th, and 137Cs, respectively. Furthermore, four important radiological hazard indices which are gamma-absorbed dose rate (D), radium equivalent activity (Raeq), external hazard index (Hex) and annual external effective dose rate (AEDout) were also evaluated by using the average values of 40K, 226Ra and 232Th. In addition, by using the AEDout value, the excess lifetime cancer risk (ELCR (outdoor)) in paddy soil in the study area would be also studied, evaluated and presented. Moreover, the evaluated TF values of required radionuclides were higher than that reported by the International Atomic Energy Agency (IAEA) in 2010 but the values were much lower than those in the study in Malaysia.
Performance of BL4.1 infrared beamline at SLRI
Authors: Artsang Pornapa , Phonthongchanthuek Thananphat , Chantharakhonm Chulalak , Nawong Siriwan , Uthaisar Chunmanus , Attarataya Jakrada , Srichan Sirinart , Tarawarakarn Pongjakr , Sittisart Krerkrit , Saiyasombat Chatree , Songsiriritthigul Prayoon
Published: December 2023

The mirror system of the infrared beamline, BL4.1, at the Synchrotron Light Research Institute was successfully re-aligned, and a new matching box was utilized to bring the collimated synchrotron-IR beam into the spectrometer. Fish sauce was used as the sample to examine the performance of the FT-IR measurements. It was found that synchrotron IR could resolve the secondary structure of amide I in the range 1600-1200 cm-1 while only the primary structure was observed when using IR from the Globar source. The absorption spectra taken using synchrotron IR exhibit a signal-to-noise ratio twice as high in the region 1290-1190 cm-1 and over ten times higher in the region 2550-2450 cm-1, comparing to those obtained by using the Globar source.
The Characterization Of Porang Starch (Amorphophallus Oncophyllus) Biodegradable Plastic Using Sorbitol Plasticizer With The Glycerol Plasticizer Addition
Authors: Maghfirah A , Susilawati  , Sofyan M Z , Siambaton M W , Sitepu S N K B , Putra O P
Published: December 2023

This research investigated effect of morphological, mechanical and physical properties on biodegradable plastic made from porang starch with chitosan using, sorbitol plasticizer at concentration 60 and 80 wt%, with the addition of glycerol plasticizer at various concentrations (0%, 25%, 50%, 75%, 100%), made using the melt intercalation method with a gelatinization temperature of 80°C and drying temperature of 70°C. Plasticizer was added to improve flexibility and water absorption of biodegradable plastic properties. Increasing the concentration of the plasticizer resulted in an increase in the elongation of the biodegradable plastic. The biodegradable plastic showed greater tensile strength before addition glycerol plasticizer 1,9191 MPa at 60% concentration and 1,3018 MPa at 80%. Conversely, the addition of 100% glycerol concentration showed an increase in elongation of 77.7764% at 60% sorbitol and 171.0562 at 80% sorbitol. SEM characterization results still showed agglomeration and FTIR not showed any new functional groups. The results of this research indicate that the percentage and kind of plasticizer influence the physical, mechanical, morphological and degradation properties to porang starch biodegradable plastics.
Differential Thermal Analysis of Polyvinyl Alcohol Nanocomposite with Rice Husk Ash as a Filler
Authors: Sirait Makmur , Sinulingga Karya , Siregar Nurdin , Doloksaribu Maryati
Published: December 2023

Nanoparticles of polyvinyl alcohol with rice husk ash as a filler for strong polymer material candidates have been prepared through the sol-gel method. Rice husk ash is a waste product obtained from the combustion of rice husks at a controlled temperature and possesses high pozzolanic properties due to its silica content. Ball milling and co-precipitation methods were employed on the rice husk ash to create nanoparticle materials. To produce nanocomposite membranes, a polyvinyl alcohol solution was utilized as a solvent through the sol-gel method. The nanocomposite samples of rice husk ash were analyzed thermally to determine the material’s response to temperature. Various nanocomposite compositions of polyvinyl alcohol and rice husk ash were used, including 0%, 1%, 2%, 3%, and 4%. Based on the thermal analysis, it is evident that there were changes in enthalpy (H) and mass characteristics in all five samples.
Calculation of Seebeck coefficient and thermal electric conductivity in single-layer NiI2 with LDA+U method
Authors: Prayitno T B , Budi E , Riyanto F A , Jaelani A
Published: December 2023

The LDA+U approach has been employed to examine the effect of the Seebeck coefficient and thermal electric conductivity in single-layer NiI2. The combination of self-consistent calculation and semi-classical Boltzmann transport has been performed to the role of magnetism in the critical temperature and room temperature. Significant tendencies were observed for some Coulomb repulsion values for different temperatures. This indicates that magnetism has a noteworthy influence on the Seebeck coefficient and thermal electric conductivity.
Increasing quantum efficiency of erbium optical medium doped lithium fluorophosphate (EDLF) as a candidate of glass-based optical amplifier
Authors: Hutahaean Juniar , Motlan  , Panggabean Jonny Haratua , Rajagukguk Juniastel , Rajagukguk Donna Helen , Sarumaha Chayani , Kaewkhao Jakrapong
Published: December 2023

Glass with composition (69-x)P2O5-20Li2O-10AlF3-xNaF-xKF-1Er2O3 (% mol) with (x = 0 ;10) was tested using melt-quenching technique. Some of the characterization carried out are identify physical properties, optical properties, luminescence, and radiation properties. Characterization using UV-vis-NIR to obtain absorption spectra in the region 380 – 1700 nm. NIR luminescence spectroscopy is used to produce a near infrared spectrum in the NIR region 1400 nm – 1700 nm. Based on the results of their radiation properties, the three glasses in this study have the potential as optical amplifier.