bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New X-Ray Tidal Disruption Event Candidate with Fast Variability
Authors: Hampel J. , Komossa S. , Greiner J. , Reiprich T. H. , Freyberg M. , Erben T. 
Published: February 2022

Abstract
During a close encounter between a star and a supermassive black hole, the star can get disrupted by the black hole’s tidal forces, resulting in a tidal disruption event (TDE). The accretion of the star’s material onto the black hole produces strong emission in different wavelength regimes. Here we report the discovery with the Roentgen Satellite (ROSAT) of an X-ray-selected transient source in an optically non-active galaxy. At the location R.A.: 13h 31m57.ˢ66 and decl.: −32°43′19.″7 a sudden rise in X-ray luminosity by a factor of 8 within 8 days has been observed. Additionally, a very soft X-ray spectrum with a blackbody temperature kT = 0.1 keV and a peak luminosity of at least 1 × 1043 erg s−1 suggests a TDE interpretation, and the observed properties are very similar to previously identified soft X-ray (ROSAT) TDEs. An optical spectrum taken of the galaxy at the position of RXJ133157.6324319.7 six years after the X-ray outburst does not show any emission lines as would be expected from a persistent active galactic nucleus. The redshift of the galaxy is determined to be 0.051 based on absorption lines. It is therefore likely a member of the galaxy cluster A3560. The rise in X-ray luminosity happens within 8 days and thus appears to be fast for such an event. No X-ray emission was detected 170 days before and 165 days after the event, and none was detected 25 yr later with the Neil Gehrels Swift Observatory. The change in X-ray luminosity is at least a factor of 40.
Efficient quantitative assessment of robot swarms: coverage and targeting Lévy strategies
Authors: Duncan S , Estrada-Rodriguez G , Stocek J , Dragone M , Vargas P A , Gimperlein H 
Published: February 2022

Abstract
Biologically inspired strategies have long been adapted to swarm robotic systems, including biased random walks, reaction to chemotactic cues and long-range coordination. In this paper we apply analysis tools developed for modeling biological systems, such as continuum descriptions, to the efficient quantitative characterization of robot swarms. As an illustration, both Brownian and Lévy strategies with a characteristic long-range movement are discussed. As a result we obtain computationally fast methods for the optimization of robot movement laws to achieve a prescribed collective behavior. We show how to compute performance metrics like coverage and hitting times, and illustrate the accuracy and efficiency of our approach for area coverage and search problems. Comparisons between the continuum model and robotic simulations confirm the quantitative agreement and speed up by a factor of over 100 of our approach. Results confirm and quantify the advantage of Lévy strategies over Brownian motion for search and area coverage problems in swarm robotics.
Effect of Inorganic Fertilizer on Morphological and Physiological Responses In ‘Siam’ (Tangerine) and ‘Keprok’ (Mandarin) Seedlings Under Nursery House
Authors: Hardiyanto  , Devy N F 
Published: February 2022

Abstract
The growth of citrus seedlings has not only been influenced by fertilizer management but also species and cultivar as well. The purpose of this study was to evaluate the growth performance of Siam and Keprok seedling to inorganic fertilizer treatment under nursery house. Research was conducted in Nursery House, ICISFRI, Batu, East Java, Indonesia from February to November 2020. Factorial Randomized Block Design was used in this research consisted of two factors, I: Doses (0 %; 50 %: 2.5 g NPK + 2.5 g ZA/plant), and II: Cultivars (Tangerine/Siam cv. Banjar, Madu, and Pontianak; Mandarin/Keprok cv. Gayo, Kacang, and Madura) with three replications. An orthogonal contrast analysis was also used to identify the response of Tangerine and Mandarin group. Among 16 variables, only plant height, leaf thickness, and shoot dry weight were significantly influenced by the interaction between doses and cultivars with value of p<0.01; R2= 98.08 %; p<0.05; R2= 85.77 %; and p<0.01; R2= 99.14 %, respectively. Eight of 16 morphological and physiological traits (50 %) applied with either 0 % or 50 % gave similar responses between Mandarin and Tangerine group. Application of 50 % and 0 % produced 68.80 % and 81.30 % of similarities between Tangerine cv. Pontianak and Banjar, respectively. Meanwhile, similarities of Tangerine (Pontianak and Banjar) versus Tangerine cv. Madu that was applied with 0 % and 50 % of fertilizer application were 68.75 and 93.75 %, respectively.
Root Growth and Yield of Rice Plant Associated with Arbuscular Mycorrhizal Symbiosis Under Salt Stress
Authors: Adillah A , Widada J , Kurniasih B 
Published: February 2022

Abstract
The presence of excessive salt around root system disrupts water and nutrient uptake by root, causes inhibition of plant growth resulting in low plant yield. Arbuscular mycorrhizal (AM) symbiosis known for its mutualism towards plant by enhancing plant root growth. This study examined how AM symbiosis improved root growth and yield of rice plant under different salinity levels. The experiment was conducted in the screenhouse of Faculty of Agriculture, Universitas Gadjah Mada which arranged in a Randomized Complete Block Design (RCBD) with two factors. The first factor was rice plant that applied with and without arbuscular mycorrhizal inoculum. The second factor was four salinity levels at 0 dS m-1 (non-saline), 2.5 dS m-1, 5 dS m-1, 7.5 dS m-1. The results showed that the increase of salinity level treatment was followed by increasing of root Na content, resulting in decreasing of root growth as well as plant yield. Higher colonization rate in mycorrhizal plant than non-mycorrhizal plant caused two-fold increase in root cation exchange capacity (CEC). Under salinity, roots of mycorrhizal plant became longer and thicker, also root fresh weight did not decrease compared to non-mycorrhizal plant. By having higher root CEC and more extensive root, mycorrhizal plant was able to alleviate yield loss under 7.5 dS m-1 salinity stress.
Adaptation of Three Local Garlics (Allium sativum L.) in Napu Plateau Central Sulawesi
Authors: Saidah  , Muchtar  , Wahyuni A N , Irmadamayanti A , Risna  , Syafruddin  , Rahayu Heni S P , Sugito  
Published: February 2022

Abstract
One of the challenges in developing garlic in Indonesia is increasing its competitiveness. It means that the price and quality must be able to compete with imported garlic. Apart from that, productivity also needs to be increased. Currently, the national demand for garlic is estimated at 539.3 thousand tons per year (2016-2019), where domestic production only reaches 134.7 tons. Therefore, the rest number is fulfilled by importing. This condition has spurred many parties to take part in supporting the garlic development program, including the Central Sulawesi provincial government. Napu Plateau in Poso District Central Sulawesi Province is an area above 1000 meter of sea level and has A rain type with agro-climatic zone A1. This condition is very suitable for the development of vegetable crops, including garlic. The research objective was to determine the adaptability of three local varieties of garlic. The activity was carried out in Watumaeta Village, North Lore Subdistrict, Poso District, Central Sulawesi in April-July 2020. The study used a Randomized Block Design with treatments of three local varieties of garlic, namely Lumbu Hijau, Sembalun and Tinombo. Number of repetitions were five units. Observed parameters included plant height, number of leaves and stem diameter, bulb diameter, bulb weight, and number of cloves. The results showed that the garlic varieties have no significant effect on all observed parameters, except stem diameter, bulb dry weight and number of cloves. Those three local varieties have average number 54,70-58,18 cm of plant height; 7,70-8,08 of leaves; 0,35-0,42 cm of stem diameter; 2,41-2,78 cm of cloves diameter; bulb dry weight 11,92-17,09 gram; 4,10-4,90 of number of cloves. Among the three local varieties, Tinombo from Parigi Moutong District was superior compare to the other two varieties.
Regulatory and Policy Responses toward SDGs in Achieving Sustainable Agriculture Productivity in Indonesia
Authors: Nasrullah  , Ovitasari M 
Published: February 2022

Abstract
As one of the countries adopted the United Nations Resolution 70/1 on the agenda entitled “Transforming Our World: 2030 for sustainable development to end hunger, achiever food security and improved nutrition and promote sustainable agriculture, Indonesia is duty bound to realize these Sustainable Development Goals (SDGs) by 2030. The purpose of this study is to identify and analyze the regulatory framework and government policy towards SDGs in achieving sustainable agricultural productivity in Indonesia. This research is normative legal research with a statutory approach and an analytical approach to the problem of agricultural development in Indonesia. By using a qualitative descriptive method, this study would describe government regulations and policies related to SDGs in achieving sustainable agricultural development. The result of this study shows that the regulations and policies set by the Government of Indonesia are in line with the Sustainable Development Goals in particular the second goal of increasing agricultural productivity in a sustainable manner especially the second SDGs goals, namely ending hunger by revitalizing agriculture and increasing the competitiveness and value added of agricultural commodities. However, this regulatory framework cannot be said to be effective in realizing sustainable agriculture productivity in Indonesia because the related regulations are not optimal and comprehensive.
Groundwater in Bener area, its quality and contribution for agriculture
Authors: Listyani T , Prabowo I A 
Published: February 2022

Abstract
The existence of surface water is not always sufficient for the needs of the community, also for agricultural needs. Therefore, groundwater can be an alternative water supply in the irrigation system, so it is necessary to assess its quality. Groundwater quality is the result of the interaction of material (soil/rock), the type of flow/transport and the change processes. The results of these components produce different groundwater quality in each region. To assess the groundwater quality in Bener and its surrounding areas, this research was carried out by direct survey in the field and testing the physical/chemical properties of groundwater in the laboratory. Groundwater sampling was carried out at 6 dug wells and 2 springs. The analysis shows that all samples are bicarbonate groundwater types, with variations of Na+, Ca2+ and Mg2+ dominant cations. Groundwater quality shows a pH value of 6.2 - 6.7, TDS of 45 - 306 ppm, hardness of 39.73 - 200.43 ppm, SAR (Sodium Adsorption Ratio) of 12.12 - 76.64, Na% of 19.81 - 62.11, and RSC (Residual Sodium Carbonate) of 0.04 - 1.35. According to its quality, groundwater can be used to support irrigation for agriculture in the area.
Soil Chemical Properties and Microbial Biomass Respond during Land Use Change
Authors: Parwi  , Muhammad  , Dewanti F D , Priyadashini R 
Published: February 2022

Abstract
In Ponorogo, East Java, Indonesia, pine-based agroforestry was mostly converted to sengon-based agroforestry before partly converted to monoculture. Land-use changes during the process affect soil properties. There is few information about the effects of land-use changes from pine-based agroforestry systems to sengon-based agroforestry systems and monocultures on soil chemical properties and microbial biomass. The aims of this study were to analyze the response of soil chemical properties and microbial biomass to land use changes in latosol Indonesian. Samples from three land-use changes, i.e. pine-based agroforestry, sengon-based agroforestry and monoculture were analyzed. Soil samples were taken at 2 depths, i. e. 0-30 cm and 30-60 cm. As the results, it was found that the land-use change affected the chemical properties and microbial biomass of the soil. Land-used change from pine-based agroforestry to sengon-based agroforestry have no significant effect on pH, organic carbon, available P, and microbial biomass in 0-30 cm depth. Meanwhile, in 30-60 cmdepth, microbial biomass in sengon-based agroforetry was higher than that in pine-based agroforestry. The pine-based agroforestry which was converted into monoculture, reduced the soil organic carbon and available P concentration, contrast with the soil microbial biomass which was increased in 0-30 cm depth. The highest soil microbial biomass was found in sengon-based agroforestry in 30-60 cm depth. The conclusion of this study implicated that land use in monoculture decreased soil fertility. Therefore, conversion of pine-based agroforestry to monoculture is full of risks.
Identification of Land Cover Types and Their Changes in Kutalimbaru Sub-district, Deli Serdang District, North Sumatra, Indonesia
Authors: Rahmawaty  , Kurniawan H , Harahap M M , Rauf A 
Published: February 2022

Abstract
In recent years, land cover changes in Deli Serdang District, North Sumatra Province, have become a problem that needs to be addressed immediately. This study aims to determine the type of land cover that has changed over a ten-year period that occurred in the Kutalimbaru Sub-district. Kutalimbaru Sub-district is upstream of the Belawan Watershed. The method used in this study is a change detection method using a geographic information system (GIS). The results showed ten types of land cover in the Kutalimbaru District: dryland forest, paddy field, mixed garden, open land, oil palm plantation, rubber plantation, settlement, shrubs, water body, and industry. Land cover in Kutalimbaru Sub-district in 2019 was dominated by mixed gardens (39.51), followed by oil palm plantations 23.13% and dryland forests 12.58%. Over ten years, there was a change in land cover from dry land forest to the mixed garden (14.42 ha) and open land (9.22 ha). A significant change occurred in land cover from mixed garden to oil palm plantation (1,783.41%) and to open land (1,178.37 ha). In addition, a change in land cover from mixed garden to settlement (154.99 ha) also occurred in this area.
Biosilica Fertilizer Reduces Fall Armyworm Damage
Authors: Ulina E S , Manurung E D , Hasibuan M , Nasution L Z 
Published: February 2022

Abstract
The presence of fall armyworm (FAW), Spodoptera frugiperda J.E. Smith, in Indonesian corn plantations caused the farmers' dependence on chemical insecticides increased. Since chemical pesticides have several side effects, it is necessary to develop another alternative to FAW management. This study aimed to investigate the efficacy of biosilica fertilizer against FAW incidence and its effect on maize production. A factorial experiment was arranged in two factors, the first factor was biosilica doses with varied doses of 1, 2, and 3 l/ha; the second factor was the number of applications at 1, 2, and 3 times. The results demonstrated that the application of biosilica fertilizer 2 - 3 l/ha as foliar spray three times starting from 10 days after growing reduced the fall armyworm infestation significantly as compared to control treatment. No significant differences were observed in the vegetative characteristics of corn plants, i.e height and the number of leaves, in response to doses and application number of biosilica. Application of biosilica 2 - 3 l/ha improved the yield attributing characters of the corn plant and increased the production as compared to other treatments including control treatment. We conclude that biosilica fertilizer can be used as an alternative for FAW management.
Insecticidal Activity of Bitter Melon (Momordica charantia L.) Leaf Extract on Mung Bean Weevil (Callosobruchus chinensis L.)
Authors: Wahyutami C T , Sarjiyah  , Aisyah S N 
Published: February 2022

AbstractInfection of mung bean weevil (Callosobruchus chinensis) might cause weight loss of mung bean seeds up to 55-69% and loss of protein content up to 45.6-66.3%. An eco-friendly strategy to manage this storage pest could be performed through the utilization of botanical pesticide, such as the leaf extract bitter melon (Momordica charantiaL.). This study was aimed to investigate the insecticidal activity of bitter melon leaf extract (BMLE) against mung bean weevil. This study was conducted using Completely Randomized Design consisting of 5 dosages of BMLE application (0, 1.4, 2.7, 5.3, and 9.6%) with 5 repetitions. BMLE was applied to 100 g of mung bean seeds, then 10 mung bean weevils were infested into the treated seeds and stored for 38 days in room temperature. Both insecticidal activity and seed quality were carefully observed during the storage period. Results showed that application of 5.3 and 9.6% BMLE exhibited similar mortality of mung bean weevil. Both dosages also showed no negative effect on the seed quality indicating that BMLE might also contribute in maintaining the seed during the storage. Therefore, these results emphasized the promising potential of BMLE to be developed as the botanical insecticide for storage pest.
Potential Use of Coconut Shell Liquid Smoke as an Insecticide on Soybean and the Impact on Agronomic Performance
Authors: Diptaningsari D , Meithasari D , Karyati H , Wardani N 
Published: February 2022

Abstract
One of the limiting factors in increasing soybean production is the high infestation of pests and diseases. Coconut shell liquid smoke has potential as a botanical insecticide on soybeans. This study was conducted to determine potential use of coconut shell liquid smoke on growth and yield of soybean compared to biological insecticide (entomopathogenic fungi) and chemical insecticide on acidic dry land in South Lampung, Lampung Province, Indonesia. The treatments were arranged with three insecticide treatments and two fertilization method (organic and inorganic fertilization), and control without insecticides and fertilizers. The intensity of pest attacks (I) was calculated using Townsend–Heuberger formula. The results showed that there was no significant difference between the treatment of three insecticide applications and two fertilization methods on the agronomic performance and yield of soybeans. Different results were shown in the control without fertilization with lower yield. Pest infestation in coconut shell liquid smoke treatment was smaller than other treatments. Coconut shell liquid smoke has the potential to be developed as a botanical insecticide, with the same results compared to chemical insecticide treatments.
Essentiality of integrated supervision of efficient mineral mining in Northern and Northeastern Russia
Authors: Yakovlev VL 
Published: February 2022

Abstract
The development strategy for deep structurally complex mineral mining and transition processes—a set of technical, technological and organizational measures to adapt geotechnical systems variable conditions of their functioning is defined. As mining is advanced and expands with the associate gain in information on geology and cost/performance, it critical to repeatedly estimate cut-off grades with regard to value of by-minerals and considering parameters of the main process flows involved in mineral extraction, pretreatment and processing. Features of the integrated mineral mining in Northern and Northeastern Russia are discussed in terms of complex concurrent development of the territories by means of creating a single infrastructure for a number of mines, including mines which extract minerals of different types.
Thermoelastic state during electrofusion welding of polyethylene pipes at different ambient temperatures
Authors: Starostin NP , Tikhonov RS 
Published: February 2022

Abstract
The problem of welding polyethylene pipes used in the mining industry at low ambient temperatures is considered The numerical solution of a thermoelastic problem revealed the distinctive features of thermal and stress-strain states of weld connections of polyethylene pipes using embedded heater couplings at different ambient temperatures. It is found that in low-temperature conditions, the size of the melted zone is considerably smaller than during welding at permissible temperatures. In this regard, the pressure insufficient for high-quality welding is created between the coupling and the pipe. It is also shown that at the time of melt crystallization, the maximum values of stresses and strains during welding at low temperatures are higher than during welding in the permissible temperature range, which causes high values of residual stresses. The results obtained can be used in the development of low temperature welding technology.
The change in physical and mechanical properties of rocks in the course of mining in Makmal Mine
Authors: Usenov KZh , Kuvakov SZh , Alibaev AP , Kuvakov ZhM , Takeeva AR 
Published: February 2022

Abstract
The geological structure of the Makmal deposit composed of metamorphic, sedimentary and intrusive rocks is discussed. The physical and mechanical of rocks ((granites, marbles, silicified ore bodies, marbled limestones, carbonate breccia, quartz-feldspar, etc.) are analyzed. The physical and mechanical properties of rocks sampled in galleries 6 and 11 in Makmal Mine are tested at a laboratory scale.
Experimental study of pneumatic impact mechanism with three pneumatic chambers
Authors: Vanag YuV 
Published: February 2022

Abstract
The problems of preserving the performance of pneumatic impact machines while reducing their weight and dimensions for carrying out the construction works in a confined space were considered. The results of calculating the dynamics of two variants of impact devices with two and three pneumatic chambers were presented. It was shown the reserve for increasing the impact power is a raise the frequency of impacts due to more number of pneumatic chambers at the same radial dimensions and threshold impact energy of the impact devices under consideration.
Limit load in the problem of penetration of a wedge-shaped tool into the rock mass
Authors: Chanyshev AI 
Published: February 2022

Abstract
The problem of penetration of an absolutely rigid round cone shaped indenter into a weighted rock (an axisymmetric plasticity problem) is being solved. Limit load, depending on the angle of internal friction of the rock, adhesion, angular opening at the top of a cone, rock weight, is determined. The dependence of loading on these parameters is given.
Determining deviation parameters when sinking horizontal wells in soil
Authors: Danilov BB , Rechkin AA 
Published: February 2022

Abstract
A schematic diagram of a device for deflecting a hole trajectory during horizontally directed auger drilling is proposed. The problem of deflector interaction with soil under static loading is considered. Using modified Cam Clay model for clay soils of the Ansys finite element package, the parametric problem on determining the dependence of well axis deflection angle and the value of well deviation per running meter of its length on the bevel angle of the front plane of rock cutting tool is solved. The optimal value of the angle is calculated.
Blade crown design for high-speed axial mine fans
Authors: Kosykh VP , Krasyuk AM , Russky EYu 
Published: February 2022

Abstract
The authors propose the aerodynamic designs for the high-rate axial main mine fans having the load capacity of 696-914 kW/m2, which is 4-5.3 times higher than the currently manufactured axial fans have. This result is achieved through the increased blade tip speed up to 220 m/s owing to the topological optimization of the material distribution within the physical volume f the blade by the minimum mass criterion. The new blades have an oriented structure and mass 50-70% less than the masses of the single-piece blades at the same allowable stresses and strains.