bluuebunny/crossref_metadata_2025 huggingface dataset:
Efektivitas Penyaluran Zakat di Baznas Kabupaten Asahan
Authors: Ayu Putri Evi , Akmal Tarigan Azhari
Published: May 2022

Zakat is an obligation for a Muslim to issue a number of property owned and given to parties who are entitled to receive it, there needs to be a measurement of effectiveness in the distribution of zakat in order to know how BAZNAS performs in zakat management and can improve the quality of performance. This study intends to measure the effectiveness of zakat distribution in BAZNAS Asahan Regency through ACR (Allocation to Collection Ratio). ACR is used to see the comparison between the funds collected with the funds that have been successfully distributed by BAZNAS. The research method used is field research of qualitative research type. The results obtained from this study are the effectiveness of zakat distribution in BAZNAS Asahan Regency in 2019 by 246%, in 2020 by 486%, with a total average ACR of 366%. With the percentage above, baznas distribution is included in the category of ACR highly effective. This means that the distribution to BAZNAS Asahan Regency is very effective. Implications of this study so that BAZNAS Asahan Regency can continue to maintain or even improve the quality of zakat distribution which currently occupies the highly-effective category.

Keywords: Effectiveness, Zakat Distribution, ACR (Allocation to Collection)
An experimental study to evaluate acute dermal toxicity of Rasakriya in Wistar rats
Authors: Hafiz Asma , Dave Omprakash , D Toshikhane Hemant
Published: May 2022

Background – Rasakriya is a herbo-mineral preparation explained under the heading of Shashti upakrama by Acharya Sushruta in the management of Dushtavrana. Safety of drugs prior to application to see its efficacy is very important as Chronic Wound is more prone for infection.

Objective – To evaluate Acute Dermal toxicity of Rasakriya on Female Wistar rats.

Materials and Methods – The study was conducted as per the OECD guidelines 402. The study was conducted under two Headings i.e. Sighting study and Limit test study. In Sighting study the prepared Rasakriya at the dose of 2000 mg/kg body weight was applied on the depilated area and observed for the signs of Toxicity for 14 days, later limit test group animals were similarly treated and observed for 14 days. Observation was done for body weight changes, clinical signs of toxicity and mortality.

Results – Dermal application of Rasakriya did not exhibit any signs toxicity with respect to Dermal, Circulatory, Respiratory, Central Nervous System and Behavioural pattern. There were no unscheduled deaths reported in animals during the study period, so, the animals were rehabilitated after the completion of the study.

Conclusion – Rasakriya is safe for application as mortality and signs of toxicity were not observed in the study.

Keywords – Rasakriya, Acute Dermal Toxicity, Sighting Study, Limit Test Study.
Simultaneous estimation of epigallocatechin, fisetin, and quercetin in Acacia suma and its potential against postprandial hyperglycemia
Authors: Kanbarkar Nikita , Mishra Sanjay , Dodmani Sunil , Kurangi Bhaskar
Published: May 2022

Anti-diabetic activity of the plants may follow one or the other mechanism such as their ability to restore the pancreatic tissue function or increase in insulin output or inhibiting the intestinal absorption of glucose or inhibiting the pancreatic enzymes like alpha-amylase, alpha-glucosidase, etc. The alpha-amylase and alpha-glucosidase inhibition assays were performed to analyze the anti-diabetic potential of Acacia suma. RP-HPLC method was developed and validated for simultaneous estimation of Epigallocatechin (EGC), Fisetin (FT), and Quercetin (QT) in hydroalcoholic extract (HAE) of Acacia suma and formulations. The simultaneous estimation was performed using the Luna C18 column with 20µl sample injection volume. Whereas, acetonitrile and phosphate buffer (0.1%, 30:70 v/v, pH 2.7) was used for resolution as mobile phase with column temperature 40 OC and flow rate 1 ml/min. The IC50 for alpha-amylase inhibition and alpha-glucosidase inhibition activity was found to be 12.5µg/ml and 93.79µg/ml respectively was compared with standards. The developed method was found simple, specific, precise and linear with regression coefficient (R2 = 0.999) over the selected range of concentration (2.5-160 μg/mL) having detection limits 0.076, 0.012, 0.010 μg/mL and quantification limits 0.231, 0.038, 0.031 μg/mL for EGC, FT and QT respectively. In-vitro alpha-amylase and alpha-glucosidase inhibition assay support the traditional claim of the plant in the treatment of metabolic disorders. The established RP-HPLC method demonstrates the precise and easy determination of EGC, FT, and QT and is effectively studied by a gradient elution system.
A case study on Psoriasis with special reference to Kitibha Kushtha
Authors: Chauhan Smita , Kumbhar Prakash , Krishna Rinjin , Patharkar Janhvi
Published: May 2022

Background: Psoriasis is a chronic non-infectious autoimmune dermatosis characterized by periodic flare-ups of sharply defined red patches, covered by a silvery, flaky surface. In Psoriasis, relapsing nature is commonly seen, which suggests the need for long-term treatment. Worldwide the prevalence of psoriasis is estimated to be approximately 2–3%. In India, the prevalence of psoriasis may vary from region to region due to variable environmental and genetic factors. Case-A 22year old nulliparous female patient suffering from psoriasis for 4 years visited the hospital for treatment. Considering the signs and symptoms of the disease, it was diagnosed as Kitibha Kushtha and Shodhan – Shaman chikitsa were planned. Conclusion:  Repeated Shodhan chikitsa helped in prevention of relapse of psoriasis and internal medications showed significant improvement in all the cardinal symptoms as well as lesions of the patients.
Synthesis of Nisha-Amalaki Yoga (NAY) Using Special Ayurveda Pharmaceutical Technique: Bhavana (Levigation/Wet Milling)
Authors: M Nisha , Deshpande Shailesh , B Rakesh , B Himangshu
Published: May 2022

Bhavana (Levigation) is a pharmaceutical process, which is preferably useful to nullify the unwanted effects of drugs and to potentiate the drug action by transforming the physical and chemical changes. In this process herbal powders are triturated along with herbal juice, decoction, or any organic liquid media till complete absorption of liquid with trituration process. This article is going to throw light on potentiation, synergistic action, increase in shelf life, and dose reduction of Nisha-Amalaki Yoga. In pharmaceutical process of Nisha-Amalaki Yoga,3 Bhavana of Emblica officinalis Gaertn. fruit juice was given to the powder of Curcuma longa L., until complete absorption of juice and dried under sunlight. Due to wet milling techniques, beneficial physicochemcal parameters changed in finished product. Weight of Choorna increased in successive manner indicating accumulation of solid particles of Emblica officinalis Gaertn. juice in Curcuma longa L. powder. Various organoleptic changes such as change of taste, change of color are also noticed. Continuous wet trituration with pressure reduced the particle size (60 to 85 mesh size) and made it compatible. GC-MS (Gas Chromatography-Mass Spectrometry) analysis revealed the presence of the major compounds such as1,1-Difluoro-Tetramethylcyclopropane (1.52%), AR-Tumerone (35.11%), 7- Curlone (55.30%) and Iso-aromadendrene epoxide/Iso-pinocarveol (8.07%). These compounds possess antidiabetic property which will be useful for upcoming clinical trial on prediabetes.
Management of severe Covid-19 cases through Ayurveda: A Case series
Authors: Jain Anuj , Phull Gaurav , Tiwari Sanjay K
Published: May 2022

The rampant destruction due to COVID is going on. So far, in modern medical system, there is no proven cure for COVID-19. The only relevant literature on the treatment of corona virus disease comes from Traditional Chinese Medicine (TCM). TCM , which is widely used to control epidemics in China, is also composed of kinds of herbs similar to Ayurveda. There is reportedly a high death rate from severe COVID-19 infection requiring oxygen support. The chest severity score as assessed by computed tomography has predictive value for future outcomes in such situations. This paper is an observational (retrospective) study of COVID-19 condition of three patient receiving Ayurvedic treatment entirely without use of any allopathic drug. There is this case series of 3 patients, 32 years old male, 38 years old female and 70 years old female. These cases were managed on the principle of Sannipatika Jwar (type of fever) along with Shwas (type of respiratory illness) with administration of Hirak bhasma, Trailokya chintamani ras, Maha lakshmi vilas ras, Abhrak bhasma, Shwaskas chintamani ras, Praval pishti, Chandramrita ras, Sitopladi churna, Mahalaxmivilas ras, Sameerpannag ras, Tab Shwas kalpa and Syp Whooping for about 10 days in different combination in these patients. The treatment resulted in complete remission of almost all the signs and symptoms. The cases were followed up after next 15 days and there were no remnant symptoms. The cases also advocated for an early Ayurvedic intervention institution for COVID-19 in prevention, deterioration and complications.
Analisa Tingkat Kecukupan Tenaga Kesehatan Dokter, Dokter Gigi, Perawat dan Bidan di Puskesmas Kabupaten Ponorogo
Authors: Ni'mah Siti Luluk Khamidahtun , Ratnawati Riska
Published: May 2022

Tujuan dari penelitian ini adalah untuk menganalisis tingkat kecukupan dokter, dokter gigi, perawat, dan bidan di Pusat Kesehatan Masyarakat wilayah Kabupaten Ponorogo. Desain penelitian bersifat deskriptif dengan pendekatan kualitatif. Responden/Informan dalam penelitian ini adalah 3 dari Dinas Kesehatan Kabupaten Ponorogo, 2 kepala puskesmas non rawat inap dan 3 kepala puskesmas rawat inap di Kabupaten Ponorogo. Hasil penelitian ini adalah analisa dari segi input yaitu jumlah dokter yang ada di seluruh puskesmas induk di kabupaten ponorogo adalah 38 orang, dokter gigi 17 orang, perawat 158 orang dan bidan 98 orang. Dari segi proses yaitu perencanaan, pengadaan, pendayagunaan dan pemberdayaan tenaga kesehatan. Dari segi output yaitu perbdaningan jumlah tenaga kesehatan yang ada saat ini dengan satdanar minimal tenaga kesehatan yang ada di permenkes no. 75 tahun 2014. Dari segi impact yaitu dampak yang ditimbulkan akibat kekurangan tenaga kesehatan tersebut. Sebaiknya Dinas Kesehatan Kabupaten Ponorogo melakukan redistribusi dan penataan kembali tenaga kesehatan agar sesuai dengan kebutuhan minimal suatu puskesmas sehingga pemerataan tenaga kesehatan dapat berjalan dengan optimal sesuai peraturan yang berlaku.
Pengetahuan tentang Perempuan Pekerja Seks terhadap Pencegahan, Tindakan Pencarian Pertolongan Pengobatan Infeksi Menular Seksual
Authors: Febrian Sukma
Published: May 2022

Tujuan penelitian ini untuk mengetahui pengetahuan perempuan dari pekerja seks terhadap pencegahan serta tindakan dari pencarian bantuan pengobatan IMS. Dengan systematic review dari study primer yang dilakukan oleh penulis sebelumnya. Penelitian ini merupakanÂ  systematic review. Artikel yang ditelusur secara komputer melalui GOOGLE SCHOLAR. Pemilihan artikel menggunakan diagram alir PRISMA. 9 artikel yang dijadikan systematic reviewmenyatakan pengetahuan PSK terkait Infeksi Menular Seksual (IMS) baik tetapi dalam praktiknya masih banyak PSKÂ  yang tidak mau menggunakan pengaman seperti kondom karna pendapatan ekonomi. Pengetahuan pekerja seks komersial dalam upaya pencegahan dapat dikatakan masuk kategori baikyaitu kesadaran PSKÂ  terhadap pekerjaan yang dilakukan memiliki resiko tinggi untuk bisa terkena penyakit IMS/HIV AIDS. Dalam praktik pencarian pertolongan pengobatan masih rendah karena tidak mau menggunakan kondom, penggunaan kondom dalam pencegahan PIMS berpengaruh pada pendapatan. Suntik KB hormon bahan-bahan tradisional serta penggunaan antibiotik masih ada dikalangan PSK dalam melakukan pencegahan dan pengobatan.
Hubungan Pengetahuan tentang Penyakit HIV/AIDS dengan Sikap Pencegahan HIV/AIDS
Authors: Prayitno Suhadi , Bachrun Edy
Published: May 2022

Tujuan penelitian ini yaitu untuk mengetahui hubungan pengetahuan dengan sikap pencegahan HIV/AIDS pada remaja. Penelitian ini merupakan jenis penelitian korelasional dengan rancangan penelitian cross-sectional. Responden sebanyak 110 siswa/i. pengumpulan data menggunakan kuesioner melalui Google Form. Analisis yang digunakan adalah Spearman Rank degan taraf signifikansi 0,05. Hasil penelitian ini, sebegaian besar pengetahuan tentang penyakitÂ  HIV/AIDS pada siswa/i di SMKN 1 Bendo Baik, dan memiliki sikap pencegahan penularan yang positif. Uji Spearman Rank didapatkan hasil Ha Diterima, sehingga ada hubungan. Selain itu didapatkan koefisien korelasi 0,347 yang berartikorelasilemah. Semakin baik tingkat pengetahuan maka akan membentuk sikap pencegahan penularan HIV/AIDS yang positif. Begitupun sebaliknya, jika pengetahuan tentang penyakit HIV/AIDS semakin kurang maka akan membentuk sikap pencegahan penularan HIV/AIDS yang negatif. Mereka yang memiliki sikap pencegahan HIV/AIDS yang positif umumnya mendukung dan sangat menyetujui upaya-upaya pencegahan penularan HIV/AIDS.
METHODOLOGICAL ASPECTS OF FORMATION OF MICROPRUDENTIAL FINANCIAL COMMUNICATIONS IN THE MEAT AND DAIRY INDUSTRY
Authors: Zhudro V.
Published: May 2022

The article outlines and substantiates the main directions of activating and increasing the formation of effective microprudential management of communications with all partners in the financial sphere in business. Particular attention is paid to the need to use interconnecting and microprudential communications with all partner enterprises in the production, investment, market and financial spheres.
Spacecraft navigation system for bodies of the Solar system
Authors:   Analytical Center, Ismagilov R.F.
Published: May 2022

The possibility of using a solar system body for spacecraft navigation, taking into account the error of navigation, is presented, and a mathematical description of navigation by one, two or more celestial bodies is considered.
The effectiveness of the use of microbiological fertilizer slavol on the development of early potatoes in the conditions of the Moscow region
Authors:   Russian State Agrarian University - Moscow Timiryazev Agricultural Academy, Dyikanova M.E. , Gasparyan I.N. ,   Russian State Agrarian University - Moscow Timiryazev Agricultural Academy, Ivashova O.N ,   Russian State Agrarian University - Moscow Timiryazev Agricultural Academy, Deniskina N.F. ,   Russian State Agrarian University - Moscow Timiryazev Agricultural Academy, Gasparyan Sh.V. ,   Russian State Agrarian University - Moscow Timiryazev Agricultural Academy
Published: May 2022

The article presents the results of a study of obtaining early potato production using microbiological fertilizer in the conditions of the Moscow region. Early potato varieties were used for the study: Udacha, Bryansk delicacy, Red Scarlett, Zhukovsky early, Meteor, Riviera. All varieties of table appointment, with high palatability and are recommended for cultivation in the Nonchernozem zone of the Russian Federation. The purpose of the research is to study the effect of the microbiological fertilizer Slavol on the growth, development of early potato plants and productivity. The experiment was carried out in 2020 ... 2021. Observations and records in the experiment were carried out according to generally accepted methods when conducting field and laboratory studies on potato crops. Mass seedlings were noted in the variants with the treatment of tubers with microbiological fertilizer Slavol, in the following sequence: variety Zhukovsky early, Meteor, Riviera, Udacha, Bryansk delicacy. The maximum total period from germination to harvesting on July 15 was longer in the variant with treatment in the Zhukovsky early variety (56 days), which further affected the increase in yield. The use of the microbiological fertilizer Slavol contributed to an increase in yield for all the studied varieties from 22.2 to 42.8%, in relation to the control variant. Thus, in the experiment, the positive effect of microbiological fertilizer Slavol on the growth, development and yield of early potato varieties in the conditions of the Moscow region was established.
BB84 quantum key distribution protocol
Authors:   Sevastopol State University, Axelrod V.A. , Kartsan I.N. ,   Sevastopol State University
Published: May 2022

The main objects of the use of promising quantum information transmission networks in the telecommunications environment are presented. The development of a new direction of the protected method of information transmission is considered. The main tasks in the use ofquantum networks in the educational environment in the training of information security specialists are formulated.
The impact of the pandemic on the global insurance market 2019-2021
Authors:   Analytical Center, Kolosov A.V.
Published: May 2022

The paper examines the impact of the pandemic on the insurance market. Analyzing and identifying various "thin spots" of the insurance business in the world, a number of solutions and innovations are presented that need to be gradually introduced to maintain sustainability. The proposed article examines in detail the dynamics of insurance of various types, mainly those that are very often used in everyday life, during financial turmoil. At the end of the article, the results are summarized, proving the importance of the development of insurance and its ability to survive in difficult times.
Taste assessment potato cultivars of collection of Krasnoyarsk Research Institute of Agriculture
Authors:   Krasnoyarsk Research Institute of Agriculture, Federal Research Center ‘Krasnoyarsk Scientific Center’ SB RAS, Lugovtsova S.Yu. , Stupko V.Yu. ,   Krasnoyarsk Research Institute of Agriculture, Federal Research Center ‘Krasnoyarsk Scientific Center’ SB RAS
Published: May 2022

The optimization of the protocols of micropropagation including micro- and minitubes development processes is carried out as a part of the program to increase the effectiveness of health-improved potato seed material production. The collection of Krasnoyarsk RIA consists of potato cultivars being most popular in the Krasnoyarsk Territory. A large amount of work to increase the reproduction index does not allow them to be carried out involving all the stocked genotypes. To select the most commercially promising varieties, a tasting of potato tubers was carried out. Both classical statistic methods and those recommended by experts as more representative, according to recent data, for processing the results of expert evaluations of products were used in the present study. Kendall's coefficient of concordance showed middle consistency of expert evaluations (W = 0,31, p<0,01). Based on Cronbach's alpha criterion the panelist making the largest contribution to the evaluation unbalance were detected. That criterion also made it possible to point out the cultivars differed from others by unbalance in taste estimation of them: Meteor, Gala, Tuleevskiy, Aramis. According to the sum of Friedman's ranks, five cultivars with the best taste qualities, combined with great demand among agricultural producers, were selected: Kolomba, Tuleevskiy, Rozara, Tanay, Gala.
Grain yield stability of wheat varieties, developed by sell selection method
Authors:   Krasnoyarsk Research Institute of Agriculture, Federal Research Center ‘Krasnoyarsk Scientific Center’ SB RAS, Stupko V.Yu. , Sidorov A.V. ,   Krasnoyarsk Research Institute of Agriculture, Federal Research Center ‘Krasnoyarsk Scientific Center’ SB RAS
Published: May 2022

The agronomic stability of the variety, along with high yields, is an indispensable condition for its zoning in risky farming areas, which include also the Krasnoyarsk Territory. The technology of cell selection under inducted stress in vitro (salinity, low pH) may produce genetic diversity based on the somaclonal variations. A comparative assessment of the yield stability of the regenerate varieties obtained by this method and of their donor genotypes was carried out. Field experiments were carried out for three years differing by moisture at the experimental production farm “Minino” near Krasnoyarsk city. The linear regression coefficient (bi) and squared deviation (s2 d) had suggested by S.A. Eberhart and W.A. Russell were used for the evaluation of varieties. A significant difference in phenotypic stability was revealed between donor varieties and regenerate ones. The regenerate varieties appeared to be better adapted to low-yielding locations (bi<0,7). However, the presence of a number of regenerate varieties, demonstrating, in comparison with the donor genotype, greater yield stability (bi → 1; s2 d → 0) with an average yield close to the original genotype, is to be noted. This shows the potential of cell selection for the stability increase of high yield varieties. In general, high variability of regenerate varieties deviation from their donor
Intelligent system of information support of the education process to improve student performance
Authors:   Siberian Federal University, Shaposhnik S.S.
Published: May 2022

This article discusses the possibility of creating and developing a personal educational environment as a tool to improve student performance in higher educational institutions. The task of this system is to track what is happening with the student in the educational institution and promptly inform him and the University management about further problems in educational activities.
Navigation control of space debris
Authors:   Reshetnev Siberian State University of Science and Technology, Kartsan I.N.
Published: May 2022

Conducted research and qualitative analysis of the effectiveness of navigational control by radio and optical means for space objects that pose a threat to further space exploration.
Capabilities of satellite navigation systems with distance from Earth
Authors:   Analytical Center, Korenkov O.V.
Published: May 2022

The possibility of using satellite navigation systems in near-Earth space and degeneracy, taking into account the distance from the Earth is considered. Presented under what conditions it is possible to receive signals from navigation satellites GPS/GLONASS, spacecraft in high orbits.
Assessing the Benefits and Costs of the Urban Forest
Authors: Dwyer John , McPherson E. Gregory , Schroeder Herbert , Rowntree Rowan
Published: May 2022

With effective planning and management, urban trees and forests will provide a wide range of important benefits to urbanites. These include a more pleasant, healthful, and comfortable environment to live, work, and play in, savings in the costs of providing a wide range of urban services, and substantial improvements in individual and community wellbeing. Urban forestry plans should begin with consideration of the contribution that trees and forests can make to people's needs. Planning and management efforts should focus on how the forest can best meet those needs. Past planning and management efforts have not been as effective as they might have been because planners and managers have underestimated the potential benefits that urban trees and forests can provide, and have not understood the planning and management efforts needed to provide those benefits, particularly the linkages between benefits and characteristics of the urban forest and its management.
Seasonal Effects on Wound Susceptibility and Canker Expansion in Honeylocusts Inoculated with Thyronectria austro-americana
Authors: Jacobi W. R.
Published: May 2022

Field-grownGleditsia triacanthosseedlings were inoculated each month for two years with the fungusThyronectria austro-americana. Resulting canker sizes were recorded monthly for one year after inoculation. The season in which inoculations occurred had a significant effect on average canker size. Canker size was largest after summer and fall inoculations, and smallest after winter and spring inoculations. Canker expansion ceased 7 - 10 months after inoculation in the fall, winter, and summer, and 3 - 4 months after spring inoculations. Thus, cankers resulting from spring inoculations were small and only expanded for a few months before host defenses stopped expansion. Cultivars (Skyline, Imperial, Sunburst) and one seedling selection (Thornless) were inoculated at 0, 7, 14, and 21 days after wounding in the spring, summer, and fall of 1986 and 1987. Wounds remained susceptible to infection between 7 and 14 days in all but one season during the experiment. In 1986, spring wounds remained susceptible for 21 days. Thus, the season of inoculation did not greatly affect the duration wounds remained susceptible.
Small Mammals in Plant Cover Types on an Electric Transmission Right-of-Way
Authors: Bramble W.C. , Yahner R.H. , Byrnes W.R. , Liscinsky S.A.
Published: May 2022

A study of the abundance and diversity of small mammals in common plant cover types was made on an electric transmission right-of-way (ROW) in central Pennsylvania in 1989 and 1990. Two mechanical and five herbicide treatments had been applied in 1987 on four replicated ROW areas. A diverse and abundant population was found on the ROW, which included eight mammalian species with an average total density of 71.0 individuals per acre. Population density of all species combined in the six common ROW cover types ranged from 32.7 in the fescue grass type to 100.4 in the witchhazel type. Density of small mammals in the adjoining forest averaged 101.6 per acre, with only two species present.
A Blockchain Based Portal for Online E-Voting
Authors: Mohammad Salahuddin  , Priyesh Kadbe  , Rajat Wanjarkar
Published: May 2022

In place of traditional electoral systems, the implementation of e-voting systems is widely adopted which still has major problems in the results. Online voting is an alternative to the old paper voting system and today's popular Electronic Vote Machine (EVM). E-voting systems are very susceptible to manipulation issues, such as alteration of election results by hacking or by the manufacturer of the voting system. To solve this problem, we use distributed ledger technology to create a voting application that is accessible to everyone and everywhere. Blockchain, which is the technology behind the first Bitcoin cryptocurrency, has attracted a lot of attention globally in recent years. This paper proposes a blockchain-based voting system that removes some limitations of existing voting systems. The application is based on the Ethereum blockchain which makes the entire system secure and immutable in nature. The presented implementation is suitable for small-scale elections such as inside corporate homes, meeting rooms, and more.
The effect of a consistent linearization on the numerical stability of hydrid-elements for quasi-incompressible hyperelastic solids
Authors: Schneider Patrick , Schönherr Josef Arthur , Mittelstedt Christian
Published: May 2022

The numerical ill-posedness of irreducible (purely displacement-based) finite element formulations for quasi-incompressible materials requires the usage of mixed formulations extended by additional primary unknowns instead. In the talk, we revisit the well-known three-field formulation introduced by Simo and Taylor, [1]. However, while in [1] a semi-discretization is used to eliminate the additional primary unknowns before the problem is linearized in terms of the not yet discretized displacement field, we introduce a consistent linearization of the three-field formulation on the continuum-level. In the latter case,  static condensation is used to eliminate the additional unknowns on the element-level after the linearization of the continuum formulation in order to derive discontinious hybrid-elements.A family of Simo-Taylor-Pister (STP) elements, as well as a family of elements based on the continuum-level linearization (CL3F), designed to coincide in terms of the  interpolation scheme, the number of assembled degrees of freedom and the number of integration points with the Abaqus hybrid-elements (C3D8H,C3D20H,C3D10H) are compared to those elements by benchmark tests. Material parameters were obtained by least-square fitting to experimental data of an industrial NR/IR-blend (natural rubber / isoprene rubber) used for damping applications.All elements are locking-free. The STP-elements show the known severe stability issues. In general the maximum stable step-width of the Abaqus hybrid-elements is way higher in comparison to the STP-elements. However, the CL3F-elements outperform the Abaqus elements in general without the usage of numerical stabilization. Especially in combination with nonlinear compression models the advantage of the CL3F is huge - here the stable step-width is up to 22-times larger. Details can be found in [2].
ANALYSIS OF THE INFLUENCE OF THE BALLAST TRACK IN THE DYNAMIC BEHAVIOUR OF SINGLE-TRACK RAILWAY BRIDGES OF DIFFERENT TYPOLOGIES
Authors: Chordà Monsonís Josep , Martínez Rodrigo Mª Dolores , Galvín Barrera Pedro , Romero Ordóñez Antonio , Moliner Cabedo Emmanuela
Published: May 2022

Abstract. In the present contribution the coupling effect of the railway track on the dynamic response of single-track bridges with several simply-supported spans is investigated. The response of such structures is of interest due to the possible appearance of high vertical accelerations at the platform, with adverse consequences such as ballast deconsolidation, loss of track stability etc., especially at resonance. Single track railway bridges due to their inherent low mass and damping, are especially critical in this regard.This paper provides a detailed sensitivity analysis over a single track railway bridge catalogue considering lengths of interest from 10 to 25 meters with different typologies: concrete filler beam and concrete slab decks, taking into account and neglecting the vertical flexibility of elastic bearings. To this end, a 2D Finite Element numerical model is implemented admitting a three-layer discrete representation of the track components mass, stiffness and damping, based on [1].The effect of the track on the bridge acceleration response is evaluated. A parametric analysis is presented with the aims of (i) detecting the track parameters that affect the most the bridge vertical acceleration response under railway traffic and (ii) determining what bridges are the most affected by the rigidity and the damping induced by the track components. Additionally, the effect of including several isostatic spans in the model is also evaluated with the goal of concluding where the maximum response occurs and what models are on the safe side.In addition, the experimental response of a real two-span railway bridge belonging to the Spanish railway conventional network is presented under operating conditions. The bridge modal properties identified in a previous work by the authors [2] are employed and the previously described numerical model is calibrated and used to simulate the structural response under railway traffic.Finally, preliminary conclusions are extracted regarding the coupling effect of the track components both at resonant and not resonant conditions.
Monolithic Finite Element Method for the simulation of thixo-viscoplastic flows
Authors: Ouazzi Abderrahim , Begum Naheed , Turek Stefan
Published: May 2022

This talk is concerned with the application of Finite Element Method (FEM) and Newton-Multigrid solver to simulate thixotropic flows.The thixotropy phenomena are introduced to yield stress material by taking into consideration the internal material micro structure using a structure parameter. Firstly, the viscoplastic stress is modified to include the thixotropic stress dependent on the structure parameter. Secondly, an evolution equation for the structure parameter is introduced to induce the time-dependent processof competition between the destruction (breakdown) and the construction (buildup) inhabited in the material. Substantially, this is done simply by introducing a structure-parameter-dependentviscosity into the rheological model for yield stress material, as for instance the Houska model based on a viscosity approach for the Bingham model [2].The modified viscoplastic stress w.r.t. the structure parameter which is integrated, in quasi-Newtonian manner or lagrangian multiplier manner, into the generalized Navier-Stokes equations and the evolution equation for the structure parameter constitutes the main core of full set of mod-eling equations, which are creditable as the privilege answer to incorporate thixotropy phenomena.The nonlinearity of the problem, related to the dependency of the diffusive stress on the material parameters, is treated with generalized Newton’s method w.r.t. the Jacobian’s singularities having a global convergence property. The linearized systems inside the outer Newton loops are solvedusing the geometrical multigrid methods with a Vanka-like smoother taking into account a stable FEM approximation pair for velocity and pressure with discontinuous pressure and biquadratic velocity spaces.We analyze the accuracy, robustness and efficiency of the Newton-Multigrid FEM solver [1] throughout the solution of thixotropic flow problems of benchmarking character in channel and Couette device [3].
On the calculation of the Kalker's creep coefficients for non-elliptical contact areas
Authors: Gómez-Bosch Jorge , Giner-Navarro Juan , Carballeira Javier
Published: May 2022

In order to properly analyse new challenges in railway dynamics, such as corrugation or rolling noise, it is necessary to obtain an accurate solution of the tangential contact problem. Traditionally, in most railway dynamic softwares, tangential contact has been calculated based on the FASTSIM algorithm. This method provides a fairly accurate solution with reduced computational cost. However, when non-Hertzian contact conditions have to be assumed, its calculations are no longer accurate, which makes FASTSIM not useful for this purpose. Also, there exist tangential contact models which are able to obtain an accurate solution for non-Hertzian conditions, but their computational cost makes them inappropriate for dynamic calculations. Therefore, this proposed new method is developed in order to satisfy the need of a model able to obtain results under non-Hertzian conditions, without an excessive computational cost.In the present work, a new extension of the FASTSIM method for the calculation of non-elliptical contact areas is proposed. The main complexity of this method lies on the calculation of the adhesion coefficients. Originally, these coefficients are obtained from Kalker’s Linear Theory, which gives exact results for elliptical contact areas, but its accuracy lowers under non-Hertzian conditions. To obtain them, a stationary contact model which assumes infinite friction coefficient is developed. This model is obtained from the kinematics of the different configurations of the wheel and the rail, and from the constitutive relations corresponding to an infinite half-space. This model is solved numerically by a collocation method (imposing the solution over the contact area). By comparison with the results obtained with reference models, the accuracy and computational cost of the proposed model is analysed. These comparisons show that the proposed model is 50 times faster than the reference model, and the errors are under 3% in most of the carried-out analysis.
A Space-Time FE Level-set method for convection coupled phase-change processes
Authors: Boledi Leonardo , Terschanski Benjamin , Elgeti Stefanie , Kowalski Julia
Published: May 2022

Phase transition processes have great relevance for both engineering and scientific applications. In production engineering, for instance, metal welding and alloy solidification are topics of ongoing research.In this contribution we focus on the convection coupled solid-liquid phase change of a single species, e.g. water. The material is assumed to be incompressible within the two phases, but we account for density changes across the phase interface. To describe the process, we need to solve the incompressible Navier-Stokes equations and the heat equation for both phases over time. The position of the phase interface is tracked with a Level-set method. The Level-set function is advected according to the propagation speed of the phase interface. Such velocity field depends on local energy conservation across the interface and is modelled as the Stefan condition. This formulation requires us to approximate the heat flux discontinuity across the interface based on the evolving temperature and velocity fields.To model the temperature and velocity fields within each phase, we employ the Space-Time Finite Element method. However, commonly used interpolation functions, such as piecewise linear functions, fail to capture discontinuous derivatives over one element that are needed to assess the Level-set's transport term. Available solutions to this matter, such as local enrichment with Extended Finite Elements, are often not compatible with existing Space-Time Finite Element codes and require extensive implementation work. Instead, we consider a conceptually simpler method and we decide to extend the Ghost Cell technique to Finite Element meshes. The idea is that we can separate the two subdomains associated with each phase and solve two independent temperature problems. We prescribe the melting temperature at an additional node close to the interface and we retrieve the required heat flux.In this work we describe the Ghost Cell method applied to our Space-Time Finite Element solver. First, we verify numerical results against analytical solutions, then we demonstrate more complex test cases in 2D and 3D.
Momentum conserving dynamic variational approach for the modeling of fiber-bending stiffness in fiber-reinforced composites
Authors: Kalaimani Iniyan , Dietzsch Julian , Gross Michael
Published: May 2022

Rotor-dynamical systems made of 3D-fiber-reinforced composites which are subjected to dynamical loads exhibit an increased fiber bending stiffness in numerical simulations. We propose a numerical modeling approach of fiber-reinforced composites that treats this behaviour accurately. Our model uses a multi-field mixed finite element formulation based on a dynamic variational approach, as demonstrated in [1], to perform long-term dynamic simulations that yield numerical solutions with increased accuracy in efficient CPU-time.We extend a Cauchy continuum with higher-order gradients of the deformation mapping as an independent field in the functional formulation, as suggested in [2], to model the bending stiffness of fibers accurately. This extended continuum also takes into account the higher-order energy contributions including the fiber curvature along with popular proven approaches that avoid the numerical locking effect of the fibers efficiently.We apply the proposed approach on Cook’s cantilever beam with a hyperelastic, transversely isotropic, polyconvex material behavior in a transient dynamic analysis. The beam is subjected to bending loads with a strong dependence of the overall stiffness on the fiber orientation. The spatial and temporal convergence as well as the conservation properties are analyzed. It is observed that the model needs an improved numerical treatment to conserve total momenta as well as total energy.REFERENCES M. Groß and J. Dietzsch, "Variational-based locking-free energy–momentum schemes of higher-order for thermo-viscoelastic fiber-reinforced continua", Computer Methods in Applied Mechanics and Engineering, (2019), 631-671, 343. T. Asmanoglo and A. Menzel, “A multi-field finite element approach for the modelling of fibre-reinforced composites with fibre-bending stiffness”, Computer Methods in Applied Mechanics and Engineering, (2017), 1037-1067, 317.
The role of dynamic sea ice in a simplified general circulation model used for palaeoclimate studies
Authors: Adam Moritz , Andres Heather J. , Rehfeld Kira
Published: May 2022

AbstractObservational records provide a strong basis for constraining sea ice models within a narrow range of climate conditions. Given current trends away from these conditions, models need to be tested over a wider range of climate states. The past provides many such examples based on paleoclimate data, including abrupt tipping points. However, the millennial-duration of typical paleoclimatesimulations necessitates balancing the inclusion and sophistication of model processes against computational cost. We investigate the impact on climate mean states and variability of introducing sea ice dynamics into the simplified general circulation model PlaSim-LSG [1-3].Considering the technical constraints of PlaSim-LSG, we choose to integrate a modied version of the MITgcm's dynamical sea ice component [4, 5] into the model setup. We adapt the component to the structure and parallelization scheme of PlaSim-LSG, validate the physical consistency and stability of the component, and evaluate the impact of sea ice dynamics onto the simulated climate from decadal to millennial time scales. Specifically, we compare climatologies, variability and scaling of the extended model to control simulations of the preexisting setups, and quantify how additional sea ice dynamics affect well-known climatic biases of the PlaSim model family.With our extended PlaSim-LSG model we aim at capturing the key small-scale sea ice processes that are important to past climate tipping points while maintaining model efficiency for millennial simulations. Sea ice is a key component of coupled atmosphere-ocean processes that led to large-amplitude, abrupt climate variability in the past [6-8]. Therefore, the extended model can be usedto investigate the role of sea ice for such oscillations. This facilitates the understanding of processes that lead to current mismatches between palaeoclimate data and simulations, and that impact thesimulated surface climate variability [9].References[1] K. Fraedrich et al. Meteorol. Z. 14.3 (2005), 299-304. doi: 10.1127/0941-2948/2005/0043.[2] F. Lunkeit et al. Tech. rep. 2011. url: https://www.mi.uni-hamburg.de/en/arbeitsgruppen/theoretische-meteorologie/modelle/sources/psreferencemanual-1.pdf.[3] H. J. Andres et al. Clim. Past 15.4 (2019), 1621-1646. doi: 10.5194/cp-15-1621-2019.[4] J. Zhang et al. J. Geophys. Res. 102.4 (1997), 412-415.[5] M. Losch et al. Ocean Model. 33.1-2 (2010), 129-144. doi: 10.1016/j.ocemod.2009.12.008.[6] T. M. Dokken et al. Paleoceanography 28.3 (2013), 491-502. doi: 10.1002/palo.20042.[7] G. Vettoretti et al. Geophys. Res. Lett. 43.10 (2016), 5336-5344. doi: 10.1002/2016GL068891.[8] C. Li et al. Quat. Sci. Rev. 203 (2019), 1-20. doi: 10.1016/j.quascirev.2018.10.031.[9] N. Weitzel et al. presented at Fall Meeting AGU. 2020. url: https://agu.confex.com/agu/fm20/webprogram/Paper739241.html.
Monolithic Newton-Multigrid Solver for Multiphase Flow Problems with Surface Tension
Authors: Afaq Muhammad Aaqib , Turek Stefan , Ouazzi Abderrahim , Fatima Arooj
Published: May 2022

We have developed a monolithic Newton-multigrid solver for multiphase flow problems which solves velocity, pressure and interface position simultaneously. The main idea of our work is based on the formulations discussed in [1], where it points out the feasibility of a fully implicit monolithic solver for multiphase flow problems via two formulations, a curvature-free level set approach and a curvature-free cutoff material function approach. Both formulations are fully implicit and have the advantages of requiring less regularity, since neither normals nor curvature are explicitly calculated, and no capillary time restriction. Furthermore, standard Navier-Stokes solvers might be used, which do not have to take into account inhomogeneous force terms. The reinitialization issue is integrated with a nonlinear terms within the formulations.The nonlinearity is treated with a Newton-type solver with divided difference evaluation of the Jacobian matrices. The resulting linearized system inside of the outer Newton solver is a typical saddle point problem which is solved using the geometrical multigrid with Vanka-like smoother using higher order stable FEM pair $Q_2/P^{\text{disc}}_1$ for velocity and pressure and $Q_2$ for all other variables. The method is implemented into an existing software packages for the numerical simulation of multiphase flows (FeatFlow). The robustness and accuracy of this solver is tested for two different test cases, i.e. static bubble and oscillating bubble, respectively [2].REFERENCES[1] Ouazzi, A., Turek, S. and Damanik, H. A curvature-free multiphase flow solver via surface stress-based formulation. Int. J. Num. Meth. Fluids., Vol. 88, pp. 18–31, (2018).[2] Afaq, M. A., Turek, S., Ouazzi, A. and Fatima, A. Monolithic Newton-Multigrid Solver for Multiphase Flow Problems with Surface Tension. Ergebnisberichte des Instituts fuer Angewandte Mathematik Nummer 636, Fakultaet fuer Mathematik, TU Dortmund University, 636, 2021.
Design and modelling of bioinspired 3D printed structures
Authors: Garrido Conrado Luis , Alabort Enrique , Barba Daniel
Published: May 2022

3D printed metamaterials are a human-designed class of material capable of providing uncommon properties unseen in nature. However the freedom power of design provided by additive manufacturing in metamaterials is useless if reliable and efficient modelling design tools are not available. The objective of this work is to evaluate, validate and study the different options for finite element simulation of bio-inspired metamaterials to provide the best solutions in terms of material properties accuracy and computational efficiency. Based on this study we have developed a new hybrid material agnostic modelling method to compute the mechanical response of beam based bioinspired metamaterials with similar precision of 3D explicit meshed models. Different variables in the latticed models were investigated, these included different element sizes and element types (volumetric and beam elements). The effects of these variables on the elastic modulus and yield strength of a lattice structure were addressed. The geometrical models were printed in Ti6Al4V using selective laser melting technique and experimentally tested for the validation of the computational results. On the basis of the volumetric results, multi-material beam models were constructed and evaluated providing with accurate results in low computational times and recreating the plastic failure phenomena observed experimentally.
A numerical scheme for two-scale phase-field models in porous media
Authors: Bastidas Manuela , Sharmin Sohely , Bringedal Carina , Pop Sorin
Published: May 2022

A porous medium is a highly complex domain, in which various processes can take place at different scales. Examples in this sense are the multi-phase flow and reactive transport. Here, due to processes like dissolution or precipitation, or chemical deposition, which are encountered at the scale of pores (the micro-scale), the local structure and geometry of the pores may change, impacting the fluid flow. Since these micro-scale processes depend on the model unknowns (e.g., the solute concentration), free boundaries are encountered, separating the space available for flow from the solid, impermeable part in the medium. Here we consider a phase-field approach to model the evolution of the evolving interfaces at the micro-scale. For mineral precipitation and dissolution, we have evolving fluid-solid interfaces. If considering multi-phase flow, evolving fluid-fluid interfaces are also present. After applying a formal homogenization procedure, a two-scale phase-field model is derived, describing the averaged behavior of the system at the Darcy scale (the macro-scale). In this two-scale model, the micro and the macro scale are coupled through the calculation of the effective parameters. Although the resulting two-scale model is less complex than the original, the numerical strategies based on the homogenization theory remain computationally expensive as they require the computation of several problems over different scales, and in each mesh element. Here, we propose an adaptive two-scale scheme involving different techniques to reduce the computational effort without affecting the accuracy of the simulations. These strategies include iterations between scales, an adaptive selection of the elements wherein effective parameters are computed, adaptive mesh refinement, and efficient non-linear solvers.