bluuebunny/crossref_metadata_2025_split huggingface dataset:
Topological, Differential Geometry Methods and Modified Variational Approach for Calculation of the Propagation Time of a Signal, Emitted by a GPS-Satellite and Depending on the Full Set of 6 Kepler Parameters
Authors: Dimitrov Bogdan G. 
Published: December 2024

Abstract
In preceding publications a mathematical approach has been developed for calculation of the propagation time of a signal, emitted by a moving along an elliptical orbit satellite and accounting also for the General Relativity Theory (GRT) Effects. So far, the formalism has been restricted to one dynamical parameter (the true anomaly or the eccentric anomaly angle). In this paper the aim is to extend the formalism to the case, when also the other five Kepler parameters will be changing and thus, the following important problem can be stated: if two satellites move on two space-distributed orbits and they exchange signals, how can the propagation time be calculated? This paper requires the implementation of differential geometry and topological methods. In this approach, the action functional for the propagation time is represented in the form of a quadratic functional in the differentials of the Kepler elements, consequently the problem is related to the first and second quadratic forms from differential geometry. Such an approach has a clear advantage, because if the functional is written in terms of Cartesian coordinates X, Y, Z, the extremum value after the application of the variational principle is shown to be the straight line - a result, known from differential geometry, but not applicable to the current problem of signal exchange between satellites on different orbits. So the known mapping from celestial mechanics is used, when by means of a transformation the 6 Kepler parameters are mapped into the cartesian coordinates X, Y, Z. This is in fact a submersion of a manifold of 6 parameters into a manifold of 3 parameters. If a variational approach is applied with respect to a differential form in terms of the differentials of the Kepler parameters, the second variation will be different from zero and the Stokes theorem can be applied, provided that the second partial derivatives of the Cartesian coordinates with respect to the Kepler parameters are assumed to be different from zero. ‘From topology this requirement is equivalent to the existence of the s.c. Morse functions (non-degenerate at the critical points). In the given case it has been shown that Morse function cannot exist with respect to each one of the Kepler parameters- Morse function cannot be defined with respect to the omega angle.
Melnikov analysis of Type I subharmonic orbits in quadruple-well coupled SD oscillators
Authors: Sun Ran , Li Jing , Zhu Shaotao 
Published: December 2024

Abstract
When appropriate parameters are selected, coupled SD oscillators can exhibit bistability, tristability, and even quadrastability. The presence of multiple potential wells introduces rich dynamical characteristics into these multi-stable systems. As a result, global dynamical analysis of quad-stable systems, particularly the study of sub-harmonic orbits, has garnered significant attention in recent years. This paper aims to investigate subharmonic motion in the quad-stable system of coupled SD oscillators and to establish a theoretical framework for Melnikov analysis of Type I subharmonic orbits. Based on the derived Melnikov function, the existence of Type I subharmonic orbits is verified. Finally, numerical simulation methods are employed to validate the proposed approach by plotting phase portrait, the time history diagram t − x and spectrum diagram.
ϕ4 model under Dirichlet-Neumann boundary conditions
Authors: Dantchev Daniel , Vassilev Vassil 
Published: December 2024

Abstract
The minimization of the Ginsburg-Landau ϕ
4 functional is at core of the so-called ϕ
4 model, which is one of the basic models of statistical mechanics. The minimization leads to a second order nonlinear differential equation that has to be solved under specific boundary conditions. In the current article we consider a system with a film geometry with thickness L under Dirichlet-Neumann boundary conditions applied along the finite-direction. We study the modifications of the bulk phase diagram for the finite system, as well as the field-temperature behavior of the characterizing the system order parameter profile, as well as the connected to it corresponding response functions (local and total susceptibilities).
Analysing the Impact of Second Gas Component on Pulse Pirani Gauge
Authors: Dankov D Y , Mironova M K , Gospodinov P N 
Published: December 2024

Abstract
This numerical study investigates the influence of a second gas component concentration on Pirani gauge readings. The analysis aims to provide insights into how the presence of additional gas components affects the accuracy and reliability of Pirani gauge measurements. By simulating different gas mixtures and examining the resulting readings, this study sheds light on the complex interactions between gases in Pirani gauge applications.
On the Lagrange and Hermite Quadrature Formula
Authors: Li Shuxia , Chen Yonghong 
Published: December 2024

Abstract
This paper builds on the error analysis method for Newton-Cotes quadrature formulas developed by D. R. Hayes and L. Rubin in 1970, which utilizes Lagrange interpolation polynomials. By adopting and extending their approach, this work derives the error estimate for Hermite interpolation quadrature. Specifically, we construct a polynomial P(x) analogous to the scaling function A(x) used by Hayes and Rubin, and prove its non-negativity over the interval. This allows us to establish a precise error formula for Hermite interpolation quadrature. The results provide a novel application of Hayes and Rubin’s methodology, offering new insights into error analysis for high-order interpolation quadrature formulas.
Seismic performance of CBF’s single steel angle brace under several variable amplitude loadings
Authors: Panjaitan Arief , Hasibuan Purwandy , Putra Rudiansyah , Afifuddin Mochammad , Haiqal Muhammad 
Published: December 2024

Abstract
Constructing seismic seismic-resistant structures is essential to be carried out in earthquake-hazard areas. A concentrically Braced Frame System (CBF) is an earthquake-resistant structure that relies on its brace to withstand seismic loading. Seismic loading is a series of loading histories composed of high (HA) and low-amplitude (LA) loading. When this loading hits the CBF system, it will perform various values of displacement. So far, many studies have been conducted to reveal seismic performance in CBF. However, studies on CBF’s response due to the variable displacement amplitude as the representation of the earthquake is still limited. This present study observed the seismic performance, i.e., strength, stiffness, and dissipated energy, of the CBF’s brace due to the variable amplitude loading. Variable amplitude loading is the loading history composed of high and low displacement amplitude levels. The brace was made of a single steel angle, L 40.40.4, and loaded with three different variable amplitude loading. Observing the dissipated energy as the main seismic performance of CBF discloses that the specimen which is loaded by the smaller number of cycles in a block amplitude reached the highest cumulative dissipated energy in the same applied displacement. This tendency is supposed to be presented since the specimen under a smaller number of loading repetitions in a block, leads to experiencing a small effect of fatigue and increases the strength in each cycle. Confirming the failure mode disclosed that all braces presented flexural and torsional buckling.
Dual superfield approach to supersymmetric mechanics with spin variables
Authors: Sidorov Stepan 
Published: December 2024

Abstract
We consider a reducible

N

=
4

, d = 1 multiplet described by a real superfield as a coupling of the mirror

(1, 4, 3)

and ordinary

(3, 4, 1)

multiplets. Employing this so-called ‘long multiplet’, we construct a coupled system of dynamical and semi-dynamical multiplets. We show that the corresponding on-shell model reproduces the model of Fedoruk, Ivanov and Lechtenfeld presented in 2012. Furthermore, there is a hidden supersymmetry acting on the long multiplet that extends the full world-line supersymmetry to SU(2

|

2). In other words, the

N

=
4

long multiplet can be derived from an irreducible SU(2

|

2) multiplet.
The Use of Sentinel-1 C-Band Dual Polarimetric and SAR Polarimetry Method for Peatland Analysis in South Kalimantan Indonesia
Authors: Ramadhani Fariidah , Bioresita Filsa , Arya Gasica Torana 
Published: December 2024

Abstract
Peatlands are a crucial factor in assessing environmental quality due to their capacity to store carbon in their biomass. Tropical peatlands, which account for 11 percent of the world’s total peatland area, are significant terrestrial carbon reservoirs, holding up to 19 percent of the global carbon. Besides carbon storage, peatlands offer numerous ecological benefits to local communities. However, Indonesia’s peat swamp forests are experiencing unprecedented rates of deforestation, drainage, and alteration. Therefore, sustainable management of peatlands through monitoring is essential. Accurate data and information on peatlands are needed for effective land management and use while maintaining hydrological functions. Synthetic Aperture Radar (SAR) is a highly efficient active remote sensing technology compared to optical remote sensing. The Polarimetric SAR method is expected to enhance the effectiveness and efficiency of peatland identification. According to the official website pantaugambut.id, Kalimantan Island has the second-largest peatland area. This research aims to identify peatlands in South Kalimantan, Indonesia, using Sentinel-1 SAR imagery. The study will evaluate the potential of the Polarimetric SAR technique with Sentinel-1 dual polarization for peatland identification. Expected outcomes include identifying peatlands and analyzing their spatial distribution. The research is intended to promote rapid and accurate peatland mapping and serve as a foundational step for global carbon monitoring. The analysis revealed that the unsupervised classification identified 26,376 hectares as peatland, achieving an overall accuracy of 85.7%, precision of 87.5%, recall of 82.4%, and a kappa value of 0.7135.
Evaluation of Vegetation Health in the PT X Reclamation Area Using the NDVI Method Based on Unmanned Aerial Vehicle (UAV) Multispectral Orthophoto Data
Authors: Prasetya Nugraha Arry , Hariyanto Teguh 
Published: December 2024

Abstract
According to the International Energy Agency (IEA) in 2023, Indonesia became the third-largest coal-producing country globally after China and India. Indonesia’s coal production amounted to 775.2 million tons in 2023, and around 27% was used for domestic needs. Coal mining in Indonesia generally uses an open-pit mining system, which impacts changes in land cover, landscape form, and the loss of flora and fauna. To dismiss this stigma, good mining practices must be applied in every process to ensure the balance of post-mining land’s natural and social functions. One effort to restore the condition of post-mining land is revegetation. Revegetation activities on ex-mining land require much time, money, and energy, so the planted vegetation must be monitored and evaluated. The problem often encountered when using Landsat and Sentinel satellite image data is that clouds cover many areas because the island of Kalimantan has a tropical climate with high rainfall, humidity, and temperature throughout the year. Then, using multispectral aerial photography data is one solution for monitoring plant health. With the advancement of photogrammetric technology using multispectral cameras, it is possible to analyze the health of reclaimed plants using the NDVI method. The results of the NDVI analysis on reclaimed plants produced the highest index value of 0.877 and the lowest value of 0.013. With very healthy plant criteria covering 12.47 ha (71.5%), healthy plant criteria covering 4.95 ha (28.4%), and unhealthy criteria covering 0.02 ha (0.1%).
Groundwater Potential Mapping Using Random Forest and Extreme Gradient Boosting Algorithms
Authors: Hidayat Agung Nugroho Wisdom , Nurwatik Nurwatik , Kusuma Widya Liadira 
Published: December 2024

Abstract
The availability of groundwater is a crucial solution to ensure the sustainability of water resources, including providing clean water. Therefore, efforts to map groundwater potential are required to enhance the efficiency of groundwater utilization and support achieving one of the Sustainable Development Goals (SDGs), particularly clean water and sanitation. This research aims to identify the distribution of the groundwater potential in Kediri Regency using the random forest (RF) and extreme gradient boosting (XGB) algorithms. This research utilizes 13 parameters, including elevation, slope, aspect, drainage density, river density, distance from rivers, lineament density, Topographic Wetness Index (TWI), Normalized Difference Vegetation Index (NDVI), land cover, soil type, lithology, and band 3 from Sentinel-2A satellite imagery. The coordinates of groundwater wells are used as training and testing data with ratios of 80:20, 70:30, and 60:40. Through the evaluation of each model’s performance using a confusion matrix, it is revealed that the best model is the RF 70:30 ratio model with Accuracy (Acc), Specificity (Spe), Sensitivity (Sen), Positive Predictive Value (PPV) values of 0.978, Cohen’s Kappa (CK) and Matthew’s Correlation Coefficient (MCC) of 0.956, and Area Under Curve (AUC) of 0.994. In this model, the elevation has the highest influence on the model, with a significance level equal to 100.
Integration of Cloud Score+ with Sentinel-2 Harmonized for land use and land cover classification using machine learning algorithms
Authors: Rifai Mohamad , Harintaka  
Published: December 2024

Abstract
West Kalimantan, Indonesia, has exotic nature reserves, with Danau Sentarum National Park (Sentarum) as its icon. Considering this importance, observing the use of Land Use Land Cover (LULC) around the lake is very important, which can be done using a remote sensing approach. Being in the equatorial region often results in continuous cloud cover throughout the year, which results in inaccurate observations and analysis results. Almost all cloud cover filters are used, but the results are often less than satisfactory. This study shows how the Cloud Score+ (CS+) product with Sentinel-2 Harmonized (S2H) can monitor image clarity in Sentarum and process it using machine learning to produce reliable (LULC) maps. Finding reasonably eliminating clouds, and clear pixels, and cloud shadows from L2A (surface reflection) or L1C (top-of-atmosphere) photos are both possible with the help of CS+ output. Using the RF algorithm, we conducted LULC research in Sentarum and produced precise results for five different LULC classes, namely water bodies, agriculture, forests, barren land, and urban. Sentinel-2 data for 2022-2023 is the basis for mapping because of anomalies that occurred in both years. In 2022, there will be extreme rainfall in Sentarum, while in 2023, the start of El Nino will begin. To identify the study area, three satellite indices were used: Normalized Difference Vegetation Index, Modified Normalized Difference Water Index, and Normalized Difference Building Index. Overall, the final results of the research in 2022 and 2023 produced an overall accuracy of 94.52% and 93.97% and a kappa index of 92.22% and 91.79%.
Investigation of Earthquake Disaster Risk Using ArcGis Satellite Imagery Study Case in North Tapanuli Regency
Authors: Faiz Nugraha Muhammad , Zaidan Mahastra Beryl , Abdillah Santoso Faried 
Published: December 2024

Abstract
Earthquakes are one of the natural phenomena that occur surprisingly without any signs or symptoms that can be felt by humans, so that generally earthquakes cause tremendous panic. Tectonic earthquakes from faults generate a Peak Ground Acceleration (PGA) value, which helps assess their risk impact. North Tapanuli Regency is one of the districts in Indonesia that is passed by two faults, namely Renun and Toru. To determine the risk of earthquake disasters in the area, calculations are carried out using spatial methods to obtain values of PGA, Mmax, and Tmax values. From the processing results, it is known that the maximum magnitude of the Toru segment is 7.37 M and the Renun segment is 7.69 M, and the Toru segment has a maximum earthquake return period in the Toru segment of 429 years and the renun segment has a return period of 1013 years. Also, a disaster mitigation map is obtained that is formed using the PGA value as a parameter, with an explanation that areas that have a higher PGA value (colored red) have a greater risk of being affected by an earthquake.
Numerical study of engine room air ventilation systems for landing ship tank class warships in supporting crew comfort and safety
Authors: Nugroho Anton , Widodo Wawan Aries , Suryo Is Bunyamin 
Published: December 2024

Abstract
The air ventilation system is one of the supporting systems in the machinery of a warship. High temperatures in the engine room can lead to an unpleasant atmosphere and, in particular, to heat stress for the operating personnel. This heat stress was caused by the design of the engine room ventilation system not meeting the requirements due to the supply and exhaust fan. Under the given conditions, the air temperature reached 50 °C, higher than the standard 45 °C. Therefore, it was necessary to conduct a thermal analysis and redesign the ventilation system using a 3D CFD (Computational Fluid Dynamic). The parameters included temperature distribution, Hlow distribution, and Hlow velocity in the engine room of the Landing Ship Tank class warship when the engine load reached 50%, 75%, and 100%. The results obtained from the simulation were in the form of quantitative data such as temperature gradients and iso contours of the air in the engine room inside the warship. The data comprised velocity contours, temperature, velocity vectors, streamlines, and particle trajectories in space. The results of the CFD approach showed that the quality of the ventilation system in the engine room inHluences extreme conditions in the engine room.
A System Dynamics Approach for Optimizing Shipping Delivery Strategies under Demand Uncertainty: A Case Study of the Fertilizer Industry
Authors: Katon Y C , Artana K B , Pujawan I N 
Published: December 2024

Abstract
The subsidized fertilizer industry faces significant supply chain costs, especially in logistics. Various specific issues require attention and resolution concerning the distribution of fertilizers. These challenges include high shipping costs, uncertain demand, limited funds, and a mismatch between requests and deliveries, which change according to need and are included in the entire supply chain. The supply chain for subsidized fertilizer is designed to be flexible and efficient, allowing for quick adjustments to changes and disruptions in plans and operations. There are complex interactions among the variables in the supply chain, wherein changes in one variable can affect others, leading to dynamic and complex situations. Due to its complexity, the research will utilize the dynamic system method to create an optimal delivery strategy. Two methods will be used: clustering for delivery location and system dynamics. Causal loop diagrams will determine the relationship between variables that influence the system, and stock and flow diagrams will be used to determine delivery routes. The output of this research compares the total cost, responsiveness, and reliability by considering two delivery scenarios: single-trip and milk-run. The results of this research successfully calculated the three outcomes and determined whether to use single-trip or milk-run for the delivery.
Buried power rail to suppress substrate leakage in complementary field effect transistor (CFET)
Authors: Jang Eungyo , Lim Jaehyuk , Shin Changhwan 
Published: December 2024

Abstract
In the pursuit of minimizing the track height in standard cell, a design innovation incorporating complementary field-effect transistors (CFETs) and Buried Power Rail (BPR) technology has been introduced. As the track height in conventional standard cells scales down to 3-track standard cell, the distance in-between the BPR metal and the bottom parasitic channel is required to be 13 nm or narrower. Consequently, a strong lateral electric-field, induced by the BPR, is applied to the substrate parasitic channel, resulting in a substrate leakage current. To address this issue, various materials for barrier/liner in the BPR structure are explored and evaluated using TCAD simulation. It turned out that the BPR-induced field effect was suppressed as the dielectric constant of the barrier material and the work function of TiN liner decreased. The proposed BPR structure demonstrates the potential to mitigate device leakage current without increasing the doping concentration in substrate.
On cyclotomic matrices involving Gauss sums over finite fields
Authors: Wu Hai-Liang , Li Jie , Wang Li-Yuan , Yip Chi Hoi 
Published: December 2024

Inspired by the works of L. Carlitz [Acta Arith. 5 (1959), pp. 293–308] and Z.-W. Sun [Finite Fields Appl. 56 (2019), pp. 285–307] on cyclotomic matrices, in this paper, we investigate certain cyclotomic matrices involving Gauss sums over finite fields, which can be viewed as finite field analogues of certain matrices related to the Gamma function.

For example, let

q
=

p
n

q=p^n

be an odd prime power with

p
p

prime and

n
∈

Z

+

n\in \mathbb {Z}^+

. Let

ζ
p

=

e

2
π

i

/

p

\zeta _p=e^{2\pi \mathbf {i}/p}

and let

χ
\chi

be a generator of the group of all multiplicative characters of the finite field

F

q

\mathbb {F}_q

. For the Gauss sum

G
q

(

χ

r

)
=

∑

x
∈

F

q

χ

r

(
x
)

ζ
p

T
r

F

q

/

F

p

(
x
)

,

\begin{equation*} G_q(\chi ^{r})=\sum _{x\in \mathbb {F}_q}\chi ^{r}(x)\zeta _p^{\mathrm {Tr}_{\mathbb {F}_q/\mathbb {F}_p}(x)}, \end{equation*}

we prove that

det

[

G
q

(

χ

2
i
+
2
j

)
]

0
≤
i
,
j
≤
(
q
−
3
)

/

2

=
(
−
1

)

α
n

(

q
−
1

2

)

q
−
1

2

2

p

n
−
1

−
1

2

,

\begin{equation*} \det \left [G_q(\chi ^{2i+2j})\right ]_{0\le i,j\le (q-3)/2}=(-1)^{\alpha _n}\left (\frac {q-1}{2}\right )^{\frac {q-1}{2}}2^{\frac {p^{n-1}-1}{2}}, \end{equation*}

where

α
n

=

{

1

a
m
p
;
if
n
≡
1

(
mod

2
)
,

(

p
2

+
7
)

/

8

a
m
p
;
if
n
≡
0

(
mod

2
)
.

\begin{equation*} \alpha _n= \begin {cases} 1 & \text {if } n\equiv 1\pmod 2,\\ (p^2+7)/8 & \text {if } n\equiv 0\pmod 2. \end{cases} \end{equation*}
State-level changes in racial disparities in probation and parole rates in the United States, 2001–2018
Authors: Rigby David , Hibi Daichi , Wygle Ruth , Lee Hedwig , Casey Joan , Gemmill Alison , Bruckner Tim 
Published: December 2024

Abstract
Although the public health field has increasingly studied the collateral consequences of incarceration, we know little about the health consequences of other forms of criminal legal contact, including probation and parole. Understanding spatial and racial-ethnic variation in probation/parole across US states provides new insights into how community supervision impacts population health disparities. However, state-level probation/parole prevalence has not been adequately described. Using data from the Bureau of Justice Statistics and the Census for the years 2001 to 2018, we provide the first state-level estimates of probation and parole populations by race over time in the US. We find large variation in disparities across states and time that is masked by national-level estimates. The US probation population decreased, and its racial composition remained steady between 2001 and 2018. However, in all but five states, the Black-White gap in probation rates declined. The Black-White gap in parole rates declined in all but seven states. The extent to which these race-specific changes in probation or parole over time reflect adjudication processes favoring White people, and/or affect population health, warrant further investigation.