bluuebunny/crossref_metadata_2025_split huggingface dataset:
A multi-stage approach for DBD modelling
Authors: Cristofolini Andrea , Popoli Arturo 
Published: June 2019

Abstract
A multi-stage numerical technique for the assessment of Dielectric Barrier Discharge (DBD) in atmospheric pressure air is presented. The model is conceived to work on the characteristic times of heavy species. The dynamics of the heavy species are computed with a 2D drift-drift diffusion model, based on a Finite Volume approach. A non-linear Poisson solver is employed for the calculation of the electric field produced by the heavy species and electrons distributions. This latter is assumed to instantly follow the Boltzmann distribution, allowing limiting the transport model to the heavy species. The main chemical reactions taking place during the discharge process between the air chemical constituents are included in the model, whereas the effects of the impact ionization are accounted by means of a simplified 1D streamer model.
Calculation of electron-impact excitation and ionisation cross sections and reaction rate coefficients for C, N and O atoms
Authors: Hleli Ali , Riahi Riadh , Teulet Philippe , Cressault Yann , Ghalila Hassen 
Published: June 2019

AbstractThis work concerns the calculation of electron-impact excitation and ionisation cross sections and reaction rate coefficients for carbon, nitrogen and oxygen atoms. Several analytical formulas proposed in the literature are used to calculate cross sections and rate coefficients for excitation of optically allowed and parity/spin forbidden transitions and for ionisation from electronic levels of the atoms. Theoretical calculations are then compared with each other and confronted to available experimental cross sections in order to deduce the most accurate analytic rate coefficient formula, which will be used in the implementation of Collisional-Radiative (CR) model for C-N-O-containing plasmas. The cross section and the reaction rate database created will be used in the development of a multi-temperature CR model allowing the determination of the population number densities inside an electric arc generated between two graphite electrodes and dedicated to the synthesis of carbon nanoparticles.
Numerical optimization of Mean Absorption Coefficient in Air using Planck Modified Mean Function
Authors: Kabbaj N , Cressault Y , Teulet P , Reichert F , Petchanka A 
Published: June 2019

Abstract
The Divergence of Radiative Flux (DRF) is the term present in the energy balance of the plasma that describes the radiative behavior of the arc. This property is obtained by the resolution of the Radiative Transfer Equation (RTE). Because of its complexity, many approximate methods are developed to reduce the computational time. This paper will describe the approximate methods already used in numerical simulation: Net Emission Coefficient (NEC) and Mean Absorption Coefficient (MAC). This last property requires having a good definition of spectral ranges and mean functions to have a physical representation of radiative losses. In this paper, the spectral ranges will be defined from the continuum of the absorption coefficient and Planck Modified Mean Function (PMMF) will be used to calculate MACs. This mean function requires a good definition of the characteristic absorption length R.
In this paper, we will develop an optimization methodology that allows finding the best R in order to have an accurate DRF using MACs. To quantify the accuracy of these approximate methods, a 1D resolution of RTE will be performed in the case of Air plasma at P=1bar in Local Thermodynamic Equilibrium (LTE). The exact DRF solution will be considered as a reference when compared with the DRF of approximate methods.
A Simple Theory for Cathode Jets in Plasma Arcs
Authors: Abdo Youssef , Rohani Vandad , Fulcheri Laurent 
Published: June 2019

Abstract

In this paper, we propose a simple and practical method for the modeling of the local and total magnetic force generated at the cathode. We prove that, if the current density profile obeys the same distribution along the axial-direction, the axial force depends only on the total current and the ratio of the arc spot radius to the radius of the arc column. We also provide an estimate for that the radial force. The power generated by Joules heating is also inserted as a term source in the energy balance equation. The use of source terms is very attractive for large scale industrial applications as it prevents from solving Maxwell’s equations that require fine meshing in the arc region and imprecise boundary conditions. It also helps to circumvent the extra complications in computation that are related to the cathode and anode falls. In the case of a mono-phase or 3-phase arc, if steady-state simulations are desired, a time-average is calculated.
Deficit irrigation for rice farming with production risk due to weather variability
Authors: Wibowo R P , Sumono  , Rizaldi T 
Published: June 2019

Abstract
Deficit irrigation is one of the keys in overcoming the problem of weather variability and limited water resources. Farmers can reduce the amount of irrigation water use without affecting too much on the productivity of rice plants by using deficit irrigation. The level of deviation of rice production increases when the water level changes between the ranges of 0-2.5 cm. The tendency to decrease from the level of deviation of agricultural production is seen when the water level increases in the range of 2.5-10 cm. At a water level of 12.5 cm there is a considerable increase in deviation. However, there was a significant decrease in the level of deviation of rice production when the water level was at 15 cm. Based on this, it can be concluded that the risk management of rice production will be better when the water level is above 2.5 cm and below 15 cm. The results of this study not only can be used for the development of risk-based farmers’ decision models but can also be used as input for the development of government policies in resource sharing and development of agricultural insurance
Diversification of products derived from maize for the sustainable welfare of the people in Gorontalo province, Indonesia
Authors: Hasan A M , Halid A , Ahmad L , Hasdiana  , Ilato R. 
Published: June 2019

Abstract
Processing industry contribution in each commodity can add value for forward linkages and backward linkages. The economic condition of Gorontalo province is as follow: contribution of regional GDP in education service is 9%, financial and insurance services’ contribution is 8%, and agricultural sector’s contribution is 4%. This shows an economic growth anomaly, where the agricultural sector as a leading sector has yet significantly contributed toward the gross regional domestic product of Gorontalo province. Our gross regional domestic product per capita is only IDR. 9,544,583 with 17.30% of poor population workforce productivity are in the 30th rank. Maize is a commodity potential to be developed into various derivative products with high economic value. This is study expected to contribute to the local government in increasing the competitive advantages and economic motor for the community in the region, as well as contribute to the private sector in developing various derivative products from maize commodity. This study uses quantitative descriptive method which constitute of desk study and secondary data analysis, workshop, and meeting with related stakeholders, development of study design for value chain actors, presentation, and result discussion to formulate the master plan and development model for various maize commodity products.
Comparing energy demand of densified briquettes of ground and unground hazelnut husks under compression loading
Authors: Demirel C , Gurdil G A K , Kabutey A , Wasserbauer M 
Published: June 2019

Abstract
The study compared the energy consumption (J) of briquettes produced from the ground and unground hazelnut husks using a universal compacting machine and a pressing chamber of 60 mm diameter with a plunger. Other parameters evaluated were deformation (mm), thickness (mm) and hardness (kN/mm). The analysis of variance results proved that the applied force, material type and interaction had a significant effect (P< 0.05 or F-ratio >F-critical) on energy requirement of briquettes compaction from the ground and unground hazelnut husks. Ground hazelnut husks briquettes consumed more energy compared to unground hazelnut husks briquettes. The study is still ongoing where the varying effects of moisture content and particles size on energy demand and other biomass densification properties are under consideration. Therefore, the results presented here are preliminary.
Repetitive loading of unroasted bulk palm kernels using UCTM for analysing optimum percentage kernel oil recovery and energy demand
Authors: Kabutey A , Herak D , Brunerova A , Sigalingging R 
Published: June 2019

Abstract
Repetitive loading test of bulk palm kernels (unroasted) was conducted to determine the percentage kernel oil yield and energy demand using the universal compression testing machine (UCTM) of the maximum load of 200 kN and speed of 5 mm min−1. Pressing vessels of varying diameters (60, 80 and 100 mm) with a plunger were used together with the UCTM. The bulk palm kernels initial height of 60 mm was repeatedly compressed until permanent deformation was reached. The total amounts of mass of kernel oil leakage, deformation, percentage kernel oil and energy were measured/calculated. The main part of the study will be done using the mechanical screw press Farmer 20 - duo (Farmer 20, Farmet a.s., Ceska Skalice, Czech Republic) to determine the optimum processing conditions for achieving maximum kernel yield and specific energy requirement.
Drying characteristic of unhulled rice in biomass energy and combination rotary dryer
Authors: Rindang A , Panggabean S , Sukoco A , Ayu P C 
Published: June 2019

Abstract
Drying of agricultural products aimed to extend the shelf life. The moisture content of the unhulled rice must be lowered to a limit of 14% to be able to maintain the quality and avoid post-harvest damage. Ciherang variety unhulled rice has been dried using biomass energy rotary dryer and biomass-heater combination for 180 minutes. In this study, several drying characteristics of unhulled rice have been analyzed including the determination of water content and the drying rate. The exponential equation illustrated the relationship between the unhulled rice water content (%) and the drying time (minutes), MC = 23.279 e−0.002t and MC = 27.255 e−0.004t respectively for the stage 1 decline drying rate in biomass energy and combination, while at the decline drying rate stage 2 found MC = 22.209 e−0.002t and MC = 27.576 e−0.004t respectively in biomass energy and combination. The relationship between unhulled rice drying rate (dM/dt) and drying time (minutes) was illustrated by the exponential equation v = 0.0466 e−0.002t and v = 0.109 e−0.004t respectively for the decline drying rate stage 1 in biomass energy and combination while at the decline drying rate stage 2, v = 0.0444 e−0.002t and v = 0.0775 e−0.003t respectively in biomass energy and combination.
Nutrient quality of oil palm frond fermented by local microorganism (MOL) with different dosage and incubation time
Authors: Tafsin M , Hanafi N D , Yunilas  , Mulianda R 
Published: June 2019

Abstract
This research purpose to know the effect of fermented feed processing technology with different dosage and incubation time towards nutrient quality of oil palm frond. The design used in the research was the factorial completely randomized design with three replicates. The treatment consist of four dosage of MOL, namely 0; 0.2; 0.4; and 0.6% for the first factor, and the second factor is incubation of time 7; 14; 21 days. The research results showed that the utilization of MOL with can significantly (P<0.05) improve nutrient quality base on proximate analysis and also on neutral detergent fibre (NDF) and acid detergent fibre (ADF) content. It is concluded that utilization of MOL can improve nutrient quality based on proximate analysis and also on neutral detergent fibre (NDF) and acid detergent fibre (ADF) content. Utilization MOL 0.6% with incubation time 21 days show the best combination treatment to improve OPF for ruminant feed.
The effect of fed maggot meal as a supplement in the commercial diets on the performance of finisher broiler chickens
Authors: Dillak S Y F G , Suryatni N P F , Handayani H T , Temu S T , Nastiti H P , Osa D B , Ginting R , Yunilas  , Henuk Y L 
Published: June 2019

Abstract
An experiment was conducted for 30 days to evaluate the performance of finisher broiler chickens fed maggot meal as a supplement in the commercial diets on their performance of finisher broiler chickens. Maggot meal was analysed to contain 40.12% CP, 10.97% CF, 6.88% EE, 15.88% ash. The four treatments used in this experiment were: (1) T0: commercial ration without maggot meal; (2) T1: commercial ration with 75% maggot meal; (3) T2: commercial ration with 50% maggot meal; and (4) T3: commercial ration added with 25% maggot meal. Statistical analyses showed that the treatments did not affect (P<0.05) feed consumption. However, they did effect (P>0.05) daily weight gain and feed efficiency of the birds. Maggot supplementation could reduce 25% commercial ration fed to broiler chickens.
Reproductive performance of buffalo-cows with various synchronization protocols in kampar regency of Riau province
Authors: Yendraliza  , Handoko J , Rodiallah M 
Published: June 2019

Abstract
The aim of this research was to compare two estrus synchronization treatments with no estrus synchronization on estrous performance, pregnancy rate and calving rate in buffalo-cows in Kampar district. A total of 60 buffalo-cows from farming communities in the villages of Tanjung, Taratak, and Salo, Kampar Regency. Variations of the estrous sync protocol included PGF2α-PGF2α and GnRH-PGF2α administered as treatments. The controls used were without the use of hormonal sync protocol. The parameters observed were the intensity of estrous, estrous percentage, onset of estrous, duration of estrous, pregnancy percentage, calving rate, duration of pregnancy, and birth weight. The results showed that there were differences [p <0.05] estrous intensity, estrous percentage [100%], estrous velocity [30.8 hours to 2.5 hours], and duration of estrous [18.6 hours to 6.5 hours]. This study concluded that the synchronization protocols of the combination of GnRH and PGF2α in post-partum buffalo-cows in Kampar Regency resulted in high estrous intensity, faster estrous appearance, and faster estrous duration.
Environmental performance, voluntary disclosure, and corporate value
Authors: Bukit R B , Nurlaila  
Published: June 2019

Abstract
This study aims to investigate the effect of environmental performance on corporate value through voluntary disclosure. This study tests all mining companies listed in Indonesia Stock Exchange during 2011-2015. The data analysis method used in this research is path analysis. This study shows the direct influence of environmental performance on company value, and also on voluntary disclosure. However, the indirect influence shows that voluntary disclosure is unable to mediate the relationship between environmental performance and company value.
Effect of pre-treatment in the making of purple-fleshed sweet potato flour towards cake characteristics
Authors: Chuango K , Julianti E , Ginting S 
Published: June 2019

Abstract
The purpose of this research was to find the effect of pre-treatment in the making of purple flesh sweet potato flour on cakes quality. The research was using factorial randomized block design with one factor, the methods of pre-treatment namely (P): (blanching, 2000 ppm soaking in sodium metabisulphite, soaking in 2000 ppm sodium metabisulphite followed by blanching and control). The results showed that the pre-treatment had highly significant effect on the colour value L, a, b and ºhue, browning index, water content and organoleptic test value of colour and had no significant effect on bulk density and organoleptic test value of aroma of the purple-fleshed sweet potato flour. The best cake was the cake made with purple-fleshed sweet potato flour with pre-treatment of blanching with 495.62 mg/L anthocyanin content, 274.08 µg/ml antioxidant activity (IC50), 22.9% moisture content and accepted organoleptic values. The result finding suggests that purple-fleshed sweet potato flour is recommended as alternative flour in producing cakes.
The effect of addition of andaliman (Zanthoxylum acanthopodium DC) on the quality of andaliman condiment
Authors: Pa E T , Sinaga H , Ridwansyah  
Published: June 2019

AbstractThe purpose of this research was to introduce the traditional food in North Sumatera and to find the effect of andaliman addition on the quality and organoleptic acceptance of condiment. The research was conducted using a non-factorial randomized block design with andaliman addition (2%, 4%, 6% and 8%) of mixture of seasoning as the factor. The results showed that the different addition of andaliman very significant different (P < 0.01) effect on organoleptic score of colour and significantly different (P < 0.05) from the moisture content, ash content, ascorbic acid, organoleptic score of bitterness, organoleptic score of taste but giving effect is not significantly different (P > 0.05) from pH value and organoleptic score of flavour.
Diversity and habitat condition of Tor Fish (Tor spp.) in the upstream of Wampu Waters, North Sumatra, Indonesia
Authors: Desrita  , Tamba I S , Muhtadi A , Ariyanti J , Leidonald R 
Published: June 2019

Abstract
The upstream of Wampu Waters is a habitat for various fish species including Tor spp fish. Fluctuating conditions of habitat will greatly affect the existence of fish as diversity, uniformity, dominance, and abundance of fish. This research was conducted to determine of the condition of habitat and diversity of Tor spp fish in the upstream of Wampu waters. Measurement of habitat conditions by measuring current velocity, depth, temperature, visibility, DO and pH. The method was used n this research is descriptive post facto with fishing using backpack electrofishing units, 12 volts and 9 amperes of battery with the multiple-pass depletion operation technique. Habitat conditions in both research locations are good and appropriate to support the life of fish of Tor spp. Tor fish species was found are Tor soro and Tor tambroides with low fish diversity index of Tor spp of 0.5 for the Bahorok River and 0.61 for the Berkail River, lowest evenness index of 0.09 was found in the Bahorok River and 0.11 in the Berkail River and lowest dominance index of 0.17 were found in the Bahorok River and 0.2 in the Berkail River.
Community structure of echinoderms in seagrass ecosystem of Pandaratan Beach, Tapanuli Tengah Regency, North Sumatera
Authors: Susetya I E , Wahyuni S , Fadhilah A , Harahap Z A , Yusni E , Saridu S A 
Published: June 2019

Abstract
This study aimed to determine the community structure of echinoderms and how it related to seagrass cover and water chemical and physical parameters in Pandaratan Beach, Tapanuli Tengah Regency. The research was conducted from Maret to April 2018. Data analysis included community structure analysis and Principal Component Analysis (PCA). The result showed that there were seven species of echinoderms from four classes in Pandaratan Beach. The station I had the highest composition of echinoderms, while the lowest noted at station II. The highest abundance of 77 ind/m2 was found at the station I and the lowest of 44 ind/m2 was at station III. The highest diversity index was recorded at the station I, while the highest evenness and dominance index was at station II. Water quality of the waters was still in capacity to support the life of echinoderms. Based on PCA analysis, it was obtained that the abundance of echinoderms was positively correlated with seagrass cover, DO, depth, and phosphate.
Biology and growth of Asiatic Hard Clam (Meretrix meretrix) population in Tanjung Balai, North Sumatera
Authors: Desrita  , Susetya I E , Suriani M , Rahman A 
Published: June 2019

Abstract
Asiatic hard clam (Meretrix meretrix) was one of molluscs (bivalve) with economical value. However, fishing activities were presumed to cause a decline in population. This condition was strengthened by the size of the clam which became smaller nowadays. The purpose of this study was to determine spatial distribution of M. meretrix, length distribution, and length-weight relationship. The study was conducted at 3 stations, consisted of Station I at Asahan River estuary which was located by mangrove forest, Station II at the sea and Station III at the waters near mainland of Batu Bara Regency. Estimation growth of M. meretrix was examined following FISAT II method. The density of M. meretrix was dominant at Station I which was low in salinity and high in organic matter. The class interval of 23-34 mm at station I dominated length distribution. Length-weight relationship was found to be very strong with determinant value approaching
Relationship between coral reef ecosystem and coral fish communities in Unggeh Island Central Tapanuli Regency
Authors: Harahap Z A , Gea Y H , Susetya I E 
Published: June 2019

Abstract
Coral reef ecosystems in Unggeh Island waters have recently declined in quality due to natural factors and human activities. The declining quality can affect the biota of the coral reef ecosystem, such as coral reef fish. Coral reef fish belong to the groups of fish whose lives are associated with the coral reef ecosystem environment. This study aims to determine the abundance and diversity of coral reef fish and the relationship between abundance of coral reef fish and the percentage of coral cover in Unggeh Island Waters, Badiri District, Central Tapanuli Regency, North Sumatra. This research was conducted in December 2017 and April 2018. The method used to observe the coral was Underwater Photo Transect (UPT) method. And the method used to observe the coral reef fish was Underwater Visual Census (UVC) method. To determine the relationship between coral cover and coral reef fish was by using a simple linear regression equation. The results showed that the relationship of coral cover with coral reef fish was in the correlation value (R) of 0.418.
The effects of potassium, nitrogen and straw compost giving to increase organic material levels and k-exchangeable rice fields and rice growth
Authors: Aminah S , Hanum H , Sarifuddin  
Published: June 2019

Abstract
Potasium and nitrogen fertilization accompanied by the application of rice straw compost is expected to improve the chemical properties of rice fields and the growth of rice plants. The purpose of this research is to find out the effect of potassium, nitrogen and straw compost fertilizer on increasing C-organic, organic matter and K-exchangeable soil and the growth of rice plants. This research was conducted in the rice field area of Cengkeh Turi village, Binjai City (± 32 m asl) from March-July 2018. This study used factorial randomized block design method with 3 Factors: Potassium (KCL): 0. 25. 50 and 75 kg ha−1; Nitrogen (Urea): dosage for farmers (250 kg ha−1) and LCC recommendations (315 kg ha−1); straw compost Treatment: without compost straw (0 t ha−1) and straw compost (5 t ha−1). The results showed that the application of potassium, nitrogen and straw compost had no significant effect on increasing levels of C-organic, organic matter and K-exchangeable paddy soil. However. There was an increase in nutrient status from very low to low. While there is a significant effect on plant height and number of tillers per clump at 2 weeks after planting and shoot dry weight of rice plants.