bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulation modeling of changes in demand for rail transportation
Authors: Zhuravleva Natalya , Guliy Ilya , Shavshukov Vyacheslav 
Published: December 2019

Abstract
The purpose of the paper is to justify the use of the intersectoral balance model for forecasting the demand for rail transportation in the face of significant changes in commodity markets. The theoretical basis of the study is the algebraic theory of the analysis of the input-output model. The methodology is based on the balance method. The modeling procedure comes down to solving a system of linear equations in which the coefficients are cost coefficients for production. The modeling information base includes scenario conditions for forecasting the socio-economic development of 40 industries and activities for which rail transportation is of decisive importance, and whose share in the structure of the GDP of Russia for the period until 2036 will change slightly. The main results of the study are: the implemented process of modeling demand for rail transportation, including a basic simulation of the intersectoral balance of the Russian economy for 2016, a predicted simulation model of demand for the period until 2030. An assessment was made of a long-term change in demand for rail transport services, taking into account structural changes affecting the activities of the main sectors of the national economy, which products are changing interspecific competition, the emergence of new product markets and digital technologies.
Development strategies for maritime farms in Crimea
Authors: Logunova N , Seryogin S , Kibenko V 
Published: December 2019

Abstract
The paper presents the results of studying current problems of mariculture industry operation. The results pinpoint factors that allow for an effective development of aquaculture sector, prove its importance for global fishing industry and its potential role in the food supply of the population of the region. The most perspective areas of development are identified based on the current world trends and actual characteristics of natural resource potential of Crimea peninsula. An accent is made on the commercial production of hydrobionts as a socially oriented field of fishing industry which allows for the preservation of ecosystem integrity and a way to become an alternative job provider, which in turn can help reach the objectives of the fishery industry in all three system areas – regional, environmental and socio-economic. Arguments are provided in favor of development of a rigid financial system, including actual means of targeted support of mariculture farms, in order to provide sustainable operation of said mariculture farms.
Ecological design based on bio-models in sustainable development
Authors: Tsitman Tatiana , Proshunina Kseniia 
Published: December 2019

Abstract
The article considers the possibilities of a new environmental approach to design. Nature presents us with such opportunities. Evolution has led to an environmentally friendly solution to the interaction of the body and its environment. Currently, architects and engineers are trying to solve the processes of environmental design approaches. It is enough to see these solutions in the bio model, to determine the laws of existence for applying its qualities in the shaping of the designed architectural object in the environment. The application of the mechanisms of functioning of the bio model will be distinguished by the originality of engineering work and aesthetic diversity. The formation of the concept allows simulating the architectural and environmental space for a specific environment. The uniqueness of the natural environment component explains the typical design decisions for specific environmental conditions. Bio models of the Astrakhan region considered to identify environmental design methodology. An analysis of the methods for adapting bio models to the landscape and climatic conditions of the considered area and their growth is necessary for the application of these methods in architectural shaping and engineering and technical support of the designed facility for specific conditions of the city of Astrakhan. Thus, the similarity of the strategy of natural components considered by steppe, floodplain, and marine plants lays the potential for creating a model in the sustainable urban development of spaces with ecological and favorable living conditions for humans and nature.
System of quality indicators of the housing and communal service of the population
Authors: Derbasova Evgeniya , Bialeckaia Elena , Mukanov Ruslan , Svintsov Vladimir 
Published: December 2019

Abstract
A set-theoretic model of the problem of assessing the quality of housing and communal services population is developed, which allows determining the necessary components and characteristics involved in the formulation of the problem, forming the input data. For resolving the problem of redundancy of indicators to assess the quality of the housing and communal service of the population, a procedure was developed to identify a minimum set of indicators. A procedure of the analysis of cognitive maps, including recommendations on elimination of redundant indicators, is considered.
Method of reducing the level of underground waters
Authors: Philipp M. , Pavlov S. , Skvortsova O. , Zinkevich I. , Nikonorov A. , Terleev V. , Volkova Y. , Nikonova O. , Terleeva A. 
Published: December 2019

Abstract
A method is proposed to calculate water irrigation rates for crops that considers hysteresis in the volumetric water content (θ)-water pressure head (ψ) relations, including scanning paths, by the method of point approximation. Three θ(ψ) models are described and computational experiments were carried out using data from literary sources on the hydrophysical properties of soils with different textures. The error analysis of the point approximation of the main branches and the predictive calculation of the scanning branches of the hysteresis loop were carried out. The practical significance of the research lies in the possibility to calculate the precise irrigation rates for crops. The use of such standards minimizes unproductive spending of irrigation water, fertilizers, ameliorants and plant protection products, as well as prevents the pollution of natural waters with agrochemicals and reduces the risk of eutrophication of water sources.
Antioxidant activity of biopigment fractions from golden apple snail eggs (Pomacea canaliculata)
Authors: Abdullah A , Nurjanah  , Seulalae A V 
Published: December 2019

Abstract
Biopigment is a natural non-toxic, renewable and environmental friendly dye. The golden apple snail eggs is known to contain carotenoid groups such as astaxanthin pigment. The purpose of this study was to determine the antioxidant activity of biopigment from acetone and methanol fractions with various in vitro test. Biopigment extracted with acetone had the highest antioxidant activity with IC50 DPPH method of 130.52±3.07 μg/mL and ABTS of 125.89±1.70 μg/mL. The result of total antioxidant capacity with FRAP method of 184.11±3.92 μmol Fe2+/g extract and CUPRAC method of 29.17±3.58 μg/mL ascorbic acid/g extract. The second fraction from acetone solvent was the best fraction with IC50 DPPH method of 92.08±2.85 μg/mL and ABTS of 144.80±3.33 μg/mL. The result of total antioxidant capacity with FRAP method of 259.11±3.93 μmol ascorbic acid g−1 extract. Identification with LC-MS/MS on the second fraction found astaxanthin pigment and five other pigments.
Quality changes of little tuna fillet (Euthynnus affinis) during chilling temperature storage
Authors: Hizbullah H H , Sari N K , Nurhayati T , Nurilmala M 
Published: December 2019

Abstract
Deterioration of fish quality affects the accumulation of metabolites, flavor changes, the formation of volatile components, as well as an increase in the number of bacteria. Chilling temperature storage is the way to maintain the quality of fish. This research was aimed to determine quality changes of little tuna (Euthynnus affinis) through organoleptic test, chemical properties and protein analysis during chilling temperature storage. Observations were conducted every 48 hours for 14 days. The parameters observed were proximate, organoleptic, pH, water-soluble protein, metmyoglobin level, and its molecular weight. Little tuna was still in fresh criteria on the 4th day with organoleptic value of 7 and was spoiled on the 10th day. The chemical composition of the fish changed during storage, increased in moisture content, decreased protein levels, and increased ash content. The values of water-soluble protein decreased during the storage while the metmyoglobin level increased during storage. In conclusion, little tuna suffered a setback in quality during 14 days of chilling temperature storage. The storage time influenced the level of water-soluble protein and the level of metmyoglobin produced.
Evaluating the protein and fat content of skipjack (Katsuwonus pelamis) in the smoking process of arabushi
Authors: Doe K , Dali F A , Harmain R M 
Published: December 2019

Abstract
Arabushi (a semi-finished product from katsuobushi) can be produced from skipjack by a gradual smoking process using varying temperatures. Different methods of smoking can cause differences in the nutrition of arabushi produced. The purpose of this study was to determine the levels of skipjack protein and fat at each smoking stage, as well as amino acid and fatty acid content of the arabushi. The smoking process was carried out by one small and medium enterprise in Bone Bolango District, Gorontalo. Smoking was carried out 7 times using temperature variations from hot to cold, namely 89°C-90°C (stage 1), 50°C-60°C (stage 2) and 40°C (stages 3 to 7). Protein content increased in each stage of smoking. Stage 1 smoked skipjack fish has a protein of 22.37%, then changed to 40.21% at stage 2 and to 58.07% at the final stage. The fat content also increased, from 20.26% at stage 1 to 27.62% at the final stage. Fifteen amino acids and 23 fatty acids were identified in the arabushi.
Analysis of sources and composition of marine debris in western and southern Aceh, Indonesia
Authors: Fitria R , Diana F , Riani E , Yulianto G , Najmi N 
Published: December 2019

Abstract
Marine debris has become an important pollution issue in recent years. Its existence has impacted to marine environment, harmed marine life, and also effected human health and lives. Marine debris study in western and southern Aceh is necessary to compare debris sources, amounts, and locations. The research outputs can provide input to the government to adopt more comprehensive policies and provide important information to targets protection in the coastal areas. Eight sites (two sites for each regency: at shoreline area and estuary stream mouth area) were selected from four regencies located in western and southern Aceh namely the regency of Aceh Jaya, west Aceh, southwestern Aceh, south Aceh. Marine debris was grouped by seven categories namely: plastic, glass, metal, rubber, cloth/fabric, processed lumber, and other/unclassifiable. The results indicated that marine debris was dominated by plastic (86.6%). The highest of debris density (0.145 items/m2) were found in southwestern Aceh and South Aceh Regency. Shoreline and recreational activities have known as the largest source of marine debris (74.8 %), followed by medical/personal hygiene activities (10.8%) dumping activities (85 items, 9.2%), smoking or related activities (4.1%) and activities related to ocean/waterway (1.1%).
Fish quality and nutritional assessment of yellowfin tuna (Thunnus albacares) during low temperature storage
Authors: Nurjanah  , Abdullah A , Naibaho I , Kartikayani D , Nurilmala M , Yusfiandayani R , Sondita M F A 
Published: December 2019

Abstract
Assessment of fish freshness is the most important and frequently difficult to determine. Moreover, fish spoilage generally depends on the temperature to control the bacterial and the autolytic development. This research was aimed to determine the quality of yellowfin tuna and skipjack tuna using physical, sensory, microbiology and chemical methods as well as their nutritional quality during certain time of freezing temperatures storage. Methods applied in this study were: organoleptic test with semi-trained panelist, pH, TPC and TVB determination monthly during 6 months of storage. Nutritional values were determined by the variation of their amino acid and lipid profiles. The results indicated that the pre-rigor phase was happened during storage until the 3rd month. In the 4th month of storage to the last month the fish samples were in the phase of rigor mortis. Organoleptic and pH value trends were decreased while the value of TPC and TVB were increased during 6 months freezing temperatures. In conclusion, during 6 months low temperature storage, the freshness quality of yellowfin and skipjack tuna as well as their nutritional value were decreased. Thus, there was fixed correlation between pH, TVB, TPC, organoleptic and nutritional values with fish freshness quality.
Tonic immobility induction and duration on halmahera walking shark (Hemischyllium halmahera)
Authors: Mukharror D A , Susiloningtyas D , Ichsan M 
Published: December 2019

Abstract
Tonic immobility is an induce method to achieve a temporary condition of cataleptic-like, which is a sudden loss of muscle tone, as a result of various procedures such as situate the object in an “unnatural” position or situation. This method has been widely applied on elasmobranch species, except for species of Hemiscyllidae. This study was intended to assess the application of tonic immobility on Hemiscyllium halmahera - an endemic shark to Halmahera Islands, Indonesia. Our study has shown that the average induction time ranged from 11.49 to 40.12 seconds, while the hypnosis duration ranged from 6.51 to 28.36 seconds. Based on our results, tonic immobility can be applied as non-lethal method to Hemiscyllium halmahera during capture and physical examination such as morphometric and weight measurement. However, we suggested to investigate further physiology examination such as heart rate, and breathing frequency. during tonic immobility phase on Halmahera walking shark or other reef shark species.
The diversity of Echinoderm in Sarangan beach, Gunung Kidul, Yogyakarta
Authors: Andilala N , Khalallia F B R , Maharani S E , Ramadhani P H , Huda A M , Putri A F , Alda B , Salsabila G , Irfan M , Ramadhanti S R , Nafiah S L , Epilurahman R 
Published: December 2019

Abstract
Sarangan beach at the coast of Gunung Kidul is dominated by substrates of sand, coral, and macroalgae where Echinodermata was found. This research was conducted to determine the diversity of echinoderms on that beach. Field observation was carried put during maximum low tide. Sampling was carried out by applying random sampling method. Specimens were preserved and identified. The sampled specimens consisted of a member of class Asteroidea (Anthenea sp), members of Ophiuroidea (Ophiocoma scolopendrina, Ophiomastix annulosa, and Ophiocoma erinaceus), members of Echinoidea (Colobocentrotus atratus, Heterocentrotus trigonarius, Stomopneustes variolaris, and Echinometra sp.).
Cavitation Damage Detection Through Acoustic Emissions
Authors: Look Andreas , Riedelbauch Stefan , Necker Jörg , Jung Alexander 
Published: December 2019

Abstract
Cavitation in hydraulic machinery is a common phenomenon with high potential for causing damage. Often it is not known whether the machinery is damaged by cavitation or cavitation occurs at all. With regard to predictive maintenance it would be advantageous not only to detect cavitation, but also to determine the current condition or damage of the hydraulic machinery. Knowing the current condition of the machinery, maintenance could be planned properly ahead and unnecessary downtime could be avoided. Since visual inspection of the current status i.e. state of cavitation and possible damage of the machinery is usually not possible due to missing optical access, acoustic inspection offers an alternative. In order to determine whether and how damage results in changes in acoustics, experiments in a controlled environment were conducted using a hydrofoil. The hydrofoil was placed in a cavitation-channel and exposed to strong cavitation for a defined period of time. Afterwards measurements of acoustic signals at different flow conditions with different cavitation conditions including no cavitation were conducted. The measurement procedure was repeated for several hundreds of times. So various measured acoustic signals of different cavitation damage states on the hydrofoil were captured. Since it was not known in which frequency region changes may occur due to cavitation damage, a broad frequency region reaching from several Hz up to 1MHz was investigated. The experiment shows promising results, such that cavitation damage at the hydrofoil results in significant changes in acoustics. Further different behavior in different frequency ranges and flow conditions can be observed.
Operation Cycle Concept for the fatigue life prediction of Francis runners
Authors: Locquenghien Florian von , Leibing Benjamin , Greck Andreas 
Published: December 2019

Abstract
A Francis runner is exposed to various loading conditions of steady and transient nature that need to be considered in a fatigue life assessment. Steady state conditions (e.g. Speed No Load, Full Load) have a constant stress amplitude pattern and therefore it is best practice to calculate a fatigue damage rate that can be multiplied by the operation time to determine fatigue damage values. Transient conditions (e.g. Start, Stop, Load Rejection) are characterized by time dependent mean stress and stress amplitudes. Traditionally, strain gauge signals are Rainflow counted and the results are evaluated using SN-curves for each separate event. With this approach, major fatigue damage driving events across operating conditions might be missed. With the introduction of the Operation Cycle Concept, the strain gauge signal is regarded from Standstill to Load to Standstill as one cycle. The influence of this approach compared to the traditional one is presented based on strain gauge measurements of Francis runners. Operating conditions with potential for optimization are identified. This knowledge is especially important for machines that are faced to flexible operation, including numerous Start-ups and Shut-downs.
Dynamic Radial Forces and Pressure Fluctuations Measurement at Off-Design Conditions on a Model Scale Pump-Turbine
Authors: Novotný V , Habán V , Skoták A , Loub R 
Published: December 2019

Abstract
The main challenge in the pump-turbines development are hydraulic instabilities in the partial loads in both pumping and generating mode. For the mechanical design of the pump-turbine shaft and bearings, it is necessary to know the magnitude of the dynamic radial forces caused by these instabilities. The radial force magnitude is usually determined on the basis of head and the runner dimensions. The paper focuses on the comparison of the empirical approach to the radial forces and the measurement on the model scale pump-turbine that was carried out in the Litostroj Engineering hydraulic laboratory in Blansko, Czech Republic. There were six strain gauges mounted on the bearing support to monitor the radial forces. In the pumping mode two distributor openings were measured. In the generating mode eight distributor openings were measured with the focus on the S-shaped curves region in the characteristic. Additionally, there were pressure gauges installed in the vaneless gap between the distributor and the runner to monitor the pressure fluctuation and potential presence of rotating stall. The appearance of rotating stall was connected to the magnitude of dynamic radial force.
Study of hydrofoil boundary layer transition using different turbulence models
Authors: Ye C L , van Esch B P M 
Published: December 2019

Abstract
Boundary layer transition is one of the key factors affecting the hydrodynamic characteristics of hydrofoil. In order to explore the capability of a transition model coupled to different turbulence models in the prediction of hydrofoil boundary layer transition, the flow field around the NACA0009 blunt-edge hydrofoil at 0°angle of attack was calculated using γ-Reθt transition model coupled with SST, SST-DES, SST-SAS, SST-DDES turbulence models. The characteristics of the hydrofoil boundary layer at ReL=2*106 are analysed. The experimental data and numerical calculation results are compared. The results show that the four turbulence models differ quite a bit in simulating hydrofoil boundary layer transition at the same calculation conditions. The flow parameters of the hydrofoil boundary layer calculated by the transition model coupled with SST-DDES are closer to the experimental results.
Experimental and numerical analysis of cavitation and pressure fluctuations in large high head propeller turbine
Authors: Ocepek Matic , Peršin Zlatko , Kern Igor , Djelić Vesko , Muhič Simon , Lipej Andrej 
Published: December 2019

Abstract
In the last decades, Computational Fluid Dynamics (CFD) has played an important role in the numerical prediction of cavitation characteristics of different types of hydraulic turbines. Relative results of the characteristics curves for different hydraulic shapes can be predicted very accurately. Usually the prediction of the absolute values of various characteristics is still a challenge. In the paper, we would like to present the comparison between the results of the model testing and numerical analysis of the critical cavitation coefficient for propeller turbine and the results of pressure fluctuation for various operating regimes.
For the numerical analysis, the cavitation model is based on the barotropic state law which describes the density change when the pressure falls below the liquid saturation pressure. Barotropic means that the density depends only on the pressure. The model tests were performed according the IEC 60193 international standards.
The results of the research contain the diagrams with sigma break curves obtained with model test and numerical analysis for different operating regimes. Furthermore, a visual observation of the cavitation on the runner blades is also presented and compared with numerically obtained cavitation regions inside the computational domain. According to the pressure fluctuations full range of operating points has been analysed and are presented.
POD analysis of a vortex rope with transient boundary conditions
Authors: Urban Ondřej , Rudolf Pavel 
Published: December 2019

Abstract
The paper presents the results of a POD analysis of the flow in a swirl generator. The generator has two separate inlets – one straight axial inlet and one tangential inlet ended by a spiral case. This allows to set different operating points, which are in turn connected with different shapes of the vortex rope present in the flow field. In this case, the investigation is aimed at linearly varying flow rates at the boundaries, namely, the ratio of the tangential flow rate is increased from 40 % up to more than 80 % of the total flow rate, which is maintained constant. Substituting the POD modes into the energy equation provides additional insight into the energy fluxes between the modes and consequently into a major part of the turbulent flow energy cascade as the input data were gained from a CFD simulation using scale-resolving Stress-Blended Eddy Simulation model. The POD modes can be used to construct a simplified model of the vortex rope dynamics covering a wider operating range rather than just one point.