This study aims to explore the concept of ethnomathematics in Samer Jumputan batik at Sentra Batik Ayu, Kedunggudel, Sukoharjo. This motif combines Javanese and Kalimantan cultural elements, such as wajik, jumputan, samer, bulu ruai, and wallet. The research employs a qualitative method with an ethnographic approach, including observation, interviews, and documentation to obtain comprehensive data. The study reveals the concepts of geometric transformation, including translation, reflection, rotation, dilation, and transformation combinations in batik patterns. The findings indicate that the Samer Jumputan motif can be used as a contextual medium in mathematics learning, particularly in geometric transformation concepts. In addition to enhancing students' understanding of mathematical concepts, this study also strengthens appreciation for local culture. Thus, batik serves as an effective educational tool while enriching culture-based learning.
Keywords: Batik Samer Jumputan, ethnomathematics, geometric transformation, culture-based learning
In this proposed work, we consider a Markovian model of two-stage tandem queueing system with retrial policy and server vacation. The arriving customers are directed to the first station for service if server is idle upon arrival. Otherwise, they will enter into the orbit for retrial. These customers will generate a continuous stream of request for service in a random period of time. After completing the first station service, the customers will enter into the second station. Once the customers receive their service in both stations, they will depart from the system forever. It is mandatory for all the arriving customers to come across both the service stations. When no more customers are present in the orbit, the servers will leave for vacation. The balance equations of birth–death transitions are solved using the recursive approach. Various system performance measures are obtained and the effect of parameters were illustrated graphically.
Can machine learning help discover new mathematical structures? In this article we discuss an approach to doing this which one can call "mathematical data science". In this paradigm, one studies mathematical objects collectively rather than individually, by creating datasets and doing machine learning experiments and interpretations. After an overview, we present two case studies: murmurations in number theory and loadings of partitions related to Kronecker coefficients in representation theory and combinatorics.
Lindi Grobler, Ryno Laubscher, Johan van der Merwe
et al.
The evaluation and accurate diagnosis of the type and severity of aortic stenosis relies on the precision of medical imaging technology and clinical correlations and the expertise of medical professionals. The application of the clinical correlation to different aortic stenosis morphologies and severities is investigated. The manner in which numerical techniques can be used to simulate the blood flow through pathological aortic valves was analysed and compared to the ground-truth CFD model. Larger pressure gradients are estimated in all severities of rheumatic aortic valves compared to calcific aortic valves. The zero-dimensional morphology-insensitive model underpredicted the transvalvular pressure gradient with the greatest error. The 1D model underestimated the pressure gradient in rheumatic cases and overestimated the pressure gradient in calcific cases. The pressure gradients estimated by the clinical approach depends on the location of the flow vena contracta and is sensitive to the severity and type of valve lesion. Through the analysis of entropy generation within the flow domain, the dominant parameters and regions driving adverse pressure gradients were identified. It is concluded that sudden expansion is the dominant parameter leading to higher pressure gradients in rheumatic heart valves compared to calcific ones.
Nur Solihah Khadhiah Abdullah, Amirul Shafiq Mokhtar, Ruhana Jaafar
et al.
Financial mismanagement poses a significant challenge for many organizations involving people from all walks of life, including students. When students enrol to further their study at a university, it might be the first time they are solely responsible for their own finance, requiring them to manage their own expenses. They might have different issues and problems in managing their finances. Financial issues among students are normal, but they cannot be overlooked as they can affect their future. Therefore, identifying the criteria that contributed to the financial mismanagement among students is very crucial. A decision-making instrument which is Fuzzy Decision-Making Trial and Evaluation Laboratory (DEMATEL), was constructed in this study. It is focusing on the selection process to calculate, rank and identify the causes and effects that contribute to the students’ financial mismanagement. Based on the analysis of six criteria, the finding shows that the criteria of spending behaviour hit the first place in the ranking order, followed by financial behaviour and financial independence. The causal diagram showed four criteria as the cause group, while two as the effect group.
Mohamed Rossaf, Khadija Mabrouk, M'hamed Ghiati
et al.
The concept of frame is an exciting, dynamic, and fast-paced subject with applications in numerous fields of mathematics and engineering. The purpose of this paper is to introduce equivalent ∗-continuous frames and to present ordinary duals of constructed ∗-continuous frames by an adjointable and invertible operator. Also, we establish some properties.
Beatris Adriana Escobedo-Trujillo, José Daniel López-Barrientos, Javier Garrido
et al.
The main objective of this work is to give conditions for the existence of Nash equilibria for a nonzero-sum constrained stochastic differential game with additive structure and Markovian switchings. In this type of game, each player is interested only in maximizing their finite-horizon total payoff when an additional cost function of the same type is required to be dominated above by another function (in particular, by a constant). The dynamic system for this game is controlled by two players and evolves according to a Markov-modulated diffusion (also known as switching diffusions or piecewise diffusion or diffusion with Markovian switchings). Given that, each player has to solve an optimization problem with constraints. The existence of a Nash equilibrium is thus proved using the Lagrange multipliers approach combined with standard dynamic programming arguments. The Lagrange approach allows the transformation of a constrained game into an unconstrained game. Therefore, this work gives conditions under which a Nash equilibrium for the unconstrained stochastic differential game is also a Nash equilibrium for the corresponding nonzero-sum constrained stochastic differential game. The theory developed here is illustrated by a pollution accumulation problem with two players. Therein, the evolution is governed by a linear stochastic differential equation with Markovian switching, and the decay pollution rate depends on a Markov chain.
Chagas disease is a zoonosis caused by the protozoan parasite Trypanosoma cruzi and transmitted by a broad range of blood-sucking triatomine species. Recently, it is recognized that the parasite can also be transmitted by host ingestion. In this paper, we propose a Chagas disease model incorporating two transmission routes of biting-defecation and host predation between vectors and hosts with Holling II functional response. The basic reproduction number R_v of triatomine population and basic reproduction numbers R_0 of disease population are derived analytically, and it is shown that they are insufficient to serve as threshold quantities to determine dynamics of the model. Our results have revealed the phenomenon of bistability, with backward and forward bifurcations. Specifically, if R_v>1, the dynamic is rather simple, namely, the disease-free equilibrium is globally asymptotically stable as R_0<1 and a unique endemic equilibrium is globally asymptotically stable as R_0>1. However, if R_v<1, there exists a backward bifurcation with one unstable and one stable positive vector equilibria, and bistability phenomenon occurs, revealing that different initial conditions may lead to disease extinction or persistence even if the corresponding R_0>1. In conclusion, predation transmission in general reduces the risk of Chagas disease, whilst it makes the complexity of Chagas disease transmission, requiring an integrated strategy for the prevention and control of Chagas disease.
Michael T. Kuczynski, Nathan J. Neeteson, Kathryn S. Stok
et al.
High resolution peripheral quantitative computed tomography (HR-pQCT) is an imaging technique capable of imaging trabecular bone in-vivo. HR-pQCT has a wide range of applications, primarily focused on bone to improve our understanding of musculoskeletal diseases, assess epidemiological associations, and evaluate the effects of pharmaceutical interventions. Processing HR-pQCT images has largely been supported using the scanner manufacturer scripting language (Image Processing Language, IPL, Scanco Medical). However, by expanding image processing workflows outside of the scanner manufacturer software environment, users have the flexibility to apply more advanced mathematical techniques and leverage modern software packages to improve image processing. The ORMIR_XCT Python package was developed to reimplement some existing IPL workflows and provide an open and reproducible package allowing for the development of advanced HR-pQCT data processing workflows.
Many land cover change detection (LCCD) approaches applied on very high resolution (VHR) remote sensing images utilize spatial information by using a regular window or strict mathematical model. However, regular shape or strict models cannot fit the various shapes and sizes of the ground targets. In this article, a novel LCCD approach without the parameter is proposed to detect land cover change with VHR remote sensing images. First, an adaptive spatial-context extraction algorithm is applied to explore contextual information around a pixel. Second, the change magnitude between pairwise pixels is quantitatively measured by computing the band-to-band distance which is defined by the pairwise adaptive regions around the corresponding pixels. Finally, after the generation of a change magnitude image (CMI), a binary threshold method called double-window flexible pace search (DFPS) is adopted to divide CMI into a binary change detection map. The performance of the proposed approach is verified by comparing it with five state-of-the-art methods with three pairs of VHR images. The comparisons demonstrated that the proposed approach achieved the improved detected results comparing with state-of-the-art LCCD methods. The code of the proposed approach is available at https://github.com/TongfeiLiu/ASEA-CD.
18 sitasi
en
Environmental Science, Computer Science
Currently, several methods have been adopted for the laboratory preparation of artificial volatile organic compound (VOC) contaminated soils (VCSs). However, it remains unclear whether the prepared contaminated soils are homogenous. In this study, two representative VOCs, toluene and perchloroethylene, were separately mixed with a kaolin-based soil using six preparation methods. Thereafter, the homogeneity and recovery of the contaminated kaolin prepared using these methods were determined and analyzed. The six procedures were quantitatively assessed according to the comprehensive evaluation mathematical model (AHP-CRITIC-TOPSIS), and the final score order of the different procedures was: A > C > E > B > F > D. Additionally, the qualitative evaluation of the procedures was performed based on the phase transformation and mass transfer during the mixing processes. Based on these discussions, method A, which was considered to be optimal, was then adopted for further investigations with various natural soils. The results showed that this optimal method could be applied to natural soils and revealed that the adsorption-related characteristics of natural soils, including total organic carbon, specific surface area, pore volume, pH, plastic limit, particle size, and mineral composition, influenced the homogeneity and recovery through mass transfer. In addition, it was also observed that the chemical properties of VOCs, including molecular structure, vapor pressure, and the octanol/water partition coefficient, could also affect the effectiveness of sample recovery. Through this study, researchers can prepare VCSs with excellent homogeneity and low loss rates to conduct standardized tests for technology development.
Esta pesquisa, de caráter exploratório e cunho qualitativo, é fruto do trabalho de conclusão do curso de Matemática Licenciatura, e tem por objetivo compreender se o processo manipulativo proporciona aprendizagem sobre o conteúdo de equações do 2º grau, ou seja, se favorece a compreensão das estratégias de resolução de equações quadráticas. O presente artigo se refere à parte teórica do trabalho, que foi realizada usando como fontes de pesquisa as produções científicas encontradas na plataforma Google Acadêmico e nos eventos do Encontro Nacional de Educação Matemática – ENEM. Ao finalizar a coleta, leitura e análise dos artigos encontrados, chegamos à conclusão de que o material dourado favorece o processo de ensino e aprendizagem do conteúdo de equações quadráticas.
Special aspects of education, Applied mathematics. Quantitative methods
Suman Maity, Sujit Kumar De, Madhumangal Pal
et al.
In this article, the parabolic dense fuzzy set is defined, and its basic arithmetic operations are studied with graphical illustration. The lock set concept is incorporated in a parabolic dense fuzzy set. Then, it is applied to the problems of fishery culture via the modeling of an economic order quantity model. Here, the fingerlings are fed to reach the ideal size to fulfill the customer’s demand. The growth rate of the fingerlings is assumed as a linear function. After the sales of all fish, the pond is cleaned properly for a new cycle. Here, the model is solved in a crisp sense first. Then, we fuzzify the model considering the demand rate as a parabolic dense lock fuzzy number and obtain the result in a fuzzy environment. The main aim of our study was to find the quantity of the ordering items such that the total inventory cost gets a minimum value. Lastly, sensitivity analysis and graphical illustrations were added for better justification of our model.
Vidal García, Raúl, Ribal Sanchis, Javier, Blasco Ruiz, Ana
Stock price determination is one of the main issues involved in the acquisition of companies. The transparency and high volume of the stock market make it possible to ascertain valuation multiples. In the case of privately-held agrifood companies, valuation multiples are scarce and barely representative. This paper focuses on answering whether listed stock valuation multiples of the agrifood industry can be useful for the purposes of valuing unlisted small and medium-sized companies. A study into Spanish unlisted agribusinesses is designed for several samples and accounting years. By means of a discounted cash flow model combined with bootstrap techniques, the empirical distribution of the unlisted multiples is obtained for three growth hypotheses. The results show that the stock market P/E should not be used in the valuation process of unlisted agrifood companies, whereas the stock market EV/EBITDA may be used in the valuation process of unlisted small and medium-sized agrifood companies that consistently obtain positive cash flows.|| La determinación del precio de las acciones es uno de los principales problemas en la adquisición de compañías. La transparencia y el alto volumen de la bolsa de valores permiten determinar múltiplos de valoración. En el caso de las empresas agroalimentarias privadas, los múltiplos de valoración son escasos y poco representativos. Este trabajo se centra en responder si los múltiplos de valor de las empresas de la industria agroalimentaria que cotizan en bolsa pueden ser útiles para valorar Pymes. Un estudio sobre compañías españolas agroalimentarias no cotizadas ha sido diseñado para varias muestras y años base. Por medio de un modelo de flujos de caja descontados, combinado con técnicas bootstrap, se ha obtenido una distribución empírica de los múltiplos de empresas no cotizadas para tres hipótesis de crecimiento. Los resultados muestran que el múltiplo EV/EBITDA bursátil puede utilizarse en el proceso de valoración de Pymes agroalimentarias no cotizadas que obtienen sistemáticamente flujos de caja positivos.
Quantitative phase imaging (QPI) is a label-free technique providing both morphology and quantitative biophysical information in biomedicine. However, applying such a powerful technique to in vivo pathological diagnosis remains challenging. Multi-core fiber bundles (MCFs) enable ultra-thin probes for in vivo imaging, but current MCF imaging techniques are limited to amplitude imaging modalities. We demonstrate a computational lensless microendoscope that uses an ultra-thin bare MCF to perform quantitative phase imaging of biomedical samples with up to 1 μm lateral resolution and nanoscale axial resolution. The incident complex light field at the measurement side is precisely reconstructed from a single-shot far-field speckle pattern at the detection side, enabling digital focusing and 3D volumetric reconstruction without any mechanical movement. The accuracy of the quantitative phase reconstruction is validated by imaging the phase target and hydrogel beads through the MCF. With the proposed imaging modality, 3D imaging of human cancer cells is achieved through the ultra-thin fiber endoscope, promising widespread clinical applications.
Purpose: To develop an automated machine-learning-based method for the discovery of rapid and quantitative chemical exchange saturation transfer (CEST) MR fingerprinting acquisition and reconstruction protocols. Methods: An MR physics governed AI system was trained to generate optimized acquisition schedules and the corresponding quantitative reconstruction neural-network. The system (termed AutoCEST) is composed of a CEST saturation block, a spin dynamics module, and a deep reconstruction network, all differentiable and jointly connected. The method was validated using a variety of chemical exchange phantoms and an in-vivo mouse brain at 9.4T. Results: The acquisition times for AutoCEST optimized schedules ranged from 35-71s, with a quantitative image reconstruction time of only 29 ms. The resulting exchangeable proton concentration maps for the phantoms were in good agreement with the known solute concentrations for AutoCEST sequences (mean absolute error = 2.42 mM; Pearson's r=0.992 , p$<$0.0001), but not for an unoptimized sequence (mean absolute error = 65.19 mM; Pearson's r=-0.161, p=0.522). Similarly, improved exchange rate agreement was observed between AutoCEST and quantification of exchange using saturation power (QUESP) methods (mean absolute error: 35.8 Hz, Pearson's r=0.971, p$<$0.0001) compared to an unoptimized schedule and QUESP (mean absolute error = 58.2 Hz; Pearson's r=0.959, p$<$0.0001). The AutoCEST in-vivo mouse brain semi-solid proton volume-fractions were lower in the cortex (12.21$\pm$1.37%) compared to the white-matter (19.73 $\pm$ 3.30%), as expected, and the amide proton volume-fraction and exchange rates agreed with previous reports. Conclusion: AutoCEST can automatically generate optimized CEST/MT acquisition protocols that can be rapidly reconstructed into quantitative exchange parameter maps.
Conditions resulting from musculoskeletal deficiencies (MSDs) are wide-ranging and retain the likelihood for restricting motion or producing pain, especially in the lower back, neck, and upper limbs. Engineered scaffold devices are being produced to replace antiquated modalities that suffer from structural and mechanical deficiencies in the treatment of MSDs. Here, as-fabricated Ti-6Al-4V-based HiveTM interbody fusion scaffolds, commercialized by HD Lifesciences LLC, were assayed for their osteogenicity and antibacterial potential using a series of characterization and in vitro tests, as well as by quantitative analyses. A topographical assessment of the HiveTM meshes indicated that the elementally pure substrates are microscopically porous and rough, in addition to displaying structural heterogeneity. Roughness estimations and static contact angle measurements recommended the use of the as-fabricated Ti-6Al-4V substrates for supporting cellular attachment, especially, due to the improved surface roughness and wettability values of these scaffolds relative to the unembellished Ti-6Al-4V surfaces. Quantitative correlations relating the surface properties of roughness and energy were applied to predict cellular behaviors. Cell growth suppositions were experimentally corroborated. Critical in vitro data indicated the competencies of HiveTM scaffolds for promoting the adhesion and proliferation of human fetal osteoblasts (hFOBs); accumulating substantial calcium buildups from metabolizing hFOBs; and restricting the attachment of bacterial biofilms. The model system that investigated the pre-adsorption of casein proteins along HiveTM test substrates additionally furthered the notion that bacterial attachment may be restricted, with short-scale adhesion dynamics serving as the theoretical basis for this hypothesis. STATEMENT OF SIGNIFICANCE: Sintered Ti-6Al-4V spinal fusion devices (HiveTM) manufactured and marketed by HD Lifesciences LLC were assessed for their biocompatibility and antibacterial performance. A mixed methods approach was employed, whereby quantitative measures were used to predict the ability for HiveTM substrates to adsorb specialized proteins and to restrict bacterial surface colonization. In vitro tests that evaluated bone cell and bacterial adhesion, calcium deposition, and protein adsorption supported quantitative predictions. The data herein presented demonstrate the following: (1) surface energy is an important predictor of implant-cell interactions, (2) strong correlations exist between surface energy and surface roughness, (3) mathematical models can be used to improve implant devices, and (4) porous, rough, 3D-printed materials perform well in terms of biocompatibility and antimicrobial efficacy.
In this paper, we propose and study a diagonal inexact version of Bregman proximal methods, to solve convex optimization problems with and without constraints. The proposed method forms a unified framework for existing algorithms by providing others.