bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on MPPT Based on Gray Wolf Algorithm improved by Levy Flight
Authors: Wang Su , Cai Wencheng , Zeng Liang
Published: April 2021

In the late iteration of the gray wolf algorithm, the convergence results will have low accuracy becased of the elite retention.When implementing MPPT control, the maximum power point of the photovoltaic array cannot be accurately tracked, and it is easy to fall into the local optimum. Therefore, this paper proposes gray wolf algorithm improved with Levy flight applied to MPPT control. The algorithm introduces the Levy flight to search the head wolf position globally, then uses the group optimization of the gray wolf algorithm and the random walk of Levy flight to improve the tracking speed and accuracy of the MPPT controller. In the simulation experiment, the algorithm is modeled and verified by setting different lighting conditions. Finally, it is compared with the conductance increment method, modified hybrid method of grey wolf optimization and golden-section optimization, the original gray wolf algorithm. The results show that the algorithm meets the requirements of fast tracking speed, high accuracy and stability in MPPT control.
A Tempered Gronwall Inequality and Its Application in Tempered Fractional Order System
Authors: Tang Yurong , Ma Nuri
Published: April 2021

Gronwall inequalities are widely used in analytical science, especially in ordinary or fractional differential systems. In this paper, a tempered Gronwall inequality is proposed and applied to tempered fractional system. By the tempered Gronwall inequality, dependences of the solution of tempered fractional systems on initial value, fractional order and tempered parameter are obtained. Finally, a new tempered fractional chaotic system is proposed to show the validity of the dependences.
Research on E-commerce Visual Marketing Analysis Based on Internet Big Data
Authors: Hu Xiaofei , Liu Jieping
Published: April 2021

Through the construction of the e-commerce vision system platform and the use of big data, the behavioural analysis of the customer groups of similarly designed products is carried out to solve the related problems in visual marketing. According to the characteristics of the user groups, the series of products are pushed out design service. Based on the current research summary of e-commerce platform marketing, the article aims at optimizing the e-commerce platform system and conducts comprehensive research from the cross perspective of marketing theory and visual design. Let the visual design system achieve precise services, promote local traditional industry e-commerce marketing conditions, achieve proactive adaptation to the new normal of economic development, and provide a reference for future design service innovation in the new era.
A Lévy Flight Based Firefly Algorithm for Multilevel Thresholding Image Segmentation
Authors: Liu Suping , Wang Yi
Published: April 2021

Traditional exhaustive search methods have high time complexity in solving multilevel threshold problems. To address this problem, a Levy flight based firefly algorithm called LFA is proposed. Otsu is regard as its objective function. A series of standard test images were used to evaluate the performance of the algorithm. The Peak signal to noise ratio(PSNR) and Structural similarity index (SSIM) are utilized to evaluate the segmented image. The experimental results show that the LFA is better than FA for multilevel thresholding image segmentation.
Image recognition and blind-guiding algorithm based on improved YOLOv3
Authors: Lu Haoyu , Ma Yan
Published: April 2021

YOLOv3, a target detection algorithm based on deep learning, is widely applied in object recognition, especially in guiding the blind. The existing products of assisting the blind based on YOLOv3 can already achieve high-precision, high-real-time object recognition. But YOLOv3 also has many limitations, such as the inability to measure distances or it’s hard to recognize objects correctly in fog or haze. For these deficiencies, this paper proposes a road barrier monitoring method based on improved YOLOv3, using an image downsampling algorithm based on the dark channel to defog the image, and then with the binocular distance measurement algorithm to calculate the obstacles from the distance of the camera according to the width and height of the obstacles. The experimental results show that the improved product retains the advantages of high accuracy and fast recognition speed of YOLOv3. At the same time, it also owns the new functions of obstacle ranging and bad weather identification. The improved algorithm can meet the requirements of portability, real-time, and practicality of guide products.
Implementation of the NewHope Protocol for Post-Quantum Cryptography
Authors: Lin Zhenghao , Chen Guanghua
Published: April 2021

In this paper, we propose a faster and less resource intensive implementation of the NewHope protocol to address the problems of resource-intensive random number generators and slow running NTT modules in NewHope implementations. In the random number generation module, choose the lightweight pseudo-random number generator (PRNG) Trivium instead of the SHAKE function to reduce the resource usage in the random number generation module. In the NTT transformation module, a pipeline structure is used in combination with a parallel structure of four butterfly units to shorten the cycle time of butterfly operations and achieve acceleration. The experimental results show that, compared with Kuo’s design, the overall time for key exchange in this paper is reduced by 25.3%, and the consumption of FFs and LUTs is reduced by 20.2% and 38.0%, respectively.
Generalized Titius-Bode Law and How to Statistically Verify it
Authors: Hu Wei
Published: April 2021

The Titius-Bode law has been historically successful in predicting the location of planets in the solar system. While the majority believes it is merely a coincidence, we too agree with that; however, we think there is some underlying universal truth hidden under the overfitting phenomena in the original Titius-Bode law; the generalized Titius-Bode, by removing the overfitting, can tell us about the mechanism of the formation of our early solar system, or more generally, all astronomical systems, as big as galaxies. Specifically, we analyzed the absolute error of the generalized Titius-Bode Law with the ground truth, and it suggested that the planets were formed iteratively, instead of each planet just magically finds its orbit where the centripetal force balances the centrifugal force.
Numerical Analysis of Hydrogen Leakage from Hydrogen Storage Container under Various Circumstances
Authors: Jin Xing , Zhou Junbo
Published: April 2021

A numerical simulation method by using the realizable k-ε model of computational fluid dynamics (CFD) proposed by establishing the model of hydrogen leakage of a high-pressure hydrogen storage container is presented in this paper. By setting different environmental wind speeds, leakage apertures, and leakage locations, multiple simulation calculations are performed to compare test results. As the wind speed increases, the degree of turbulence of hydrogen increases. Large aperture and bottom side leakage cause more serious hazardous area of personnel than small aperture and top leakage do. Base on the results, it can provide reference for dealing with the leakage of high-pressure hydrogen storage containers.
The Numerical Simulation of the Vertical Water Entry Process of High Speed Projectile with Small Angle of Attack
Authors: Li Ruijie , Wang Rui , Yao Zhong , Sun Yanhu , Wang Jiawen
Published: April 2021

Based on the numerical simulation method, the high speed vertical water entry process of projectile moving at 1000m/s with small angle of attack is studied. By analyzing the cavity configuration and hydrodynamic characteristics of the process, the influences of the small entry angle on the water entry stability process are obtained. The simulation results indicate that the projectile’s ballistic can achieve relative stable state when the water entry angle is less than 0.5°, otherwise the water entry cavity can be pierced by tail fin. The pierced size tend to increase with the increased water entry angle as well as the projectile’s ballistic become unstable. In addition, the rotation of the projectile owing to pitching moment has little effect on cavity configuration and water entry stability.
A quantum-inspired particle swarm optimization for sizing optimization of truss structures
Authors: Xu Zhiqiang , Cui Yunxian , Li Baoliang
Published: April 2021

Particle swarm optimization (PSO) algorithm has some advantages such as simple principle, less model parameters. However, it has some flaws for dealing with sizing optimization of truss structures, such as low accuracy, slow astringency and poor population diversity in the later evolution stage. In order to overcome these shortcomings and deal with optimization problem of truss structures effectively, a new quantum-inspired particle swarm optimization (QPSO) algorithm with quantum angle encoding and a perturbation operator of the population is proposed in this paper. Then, QPSO is used for optimization of truss structures by means of penalty function method. In the end, two typical numerical tests for truss design are performed to calibrate and verified the proposed algorithm. The results of the QPSO compared with PSO and other optimization algorithms show that the proposed QPSO has a better performance in terms of both the optimum solutions and the convergence capability than PSO and is a powerful optimization technique for solving optimization problem of truss structures.
Research on Innovative Practice Links of Physical Education Course Based on Computer Big Data
Authors: Jiang Ren
Published: April 2021

The thesis uses literature research, information research methods, and logical reasoning methods. After in-depth research on the current situation of the development of school sports activities between classes, it is found that some schools still adopt the form of interclass exercises due to insufficient hardware or software facilities. The problem is that there is very little communication between schools, and the school itself has no position in the inter-class activities of sports. To fill this gap, we must not only strengthen policies, but also integrate with the rapid development of modern information. In the era of big data, the traditional physical education teaching model is being impacted and challenged. College students no longer like the passive “indoctrination” teaching model, but prefer to explore the autonomous learning method. How does the teaching of sports innovation practice adapt to the era of big data? Development is worth pondering, and it is of great significance to explore teaching models that are conducive to cultivating students’ autonomous learning ability and inquiry ability.
Two Types of Second Order Fractional Differential Equations
Authors: Yu Chii-Huei
Published: April 2021

In this paper, we make use of a new multiplication of fractional functions, variable separation method and chain rule for fractional derivatives, regarding the Jumarie type of modified Riemann-Liouville (R-L) fractional derivatives to solve two types of second order fractional differential equations. Moreover, some examples are proposed to illustrate our results.
Research on College English Teaching System Based on Computer Big Data
Authors: Zhu Weihua
Published: April 2021

With the development and maturity of computer and multimedia technology, computer-aided teaching represents advanced teaching ideas and teaching methods. Computer-aided learning systems can dynamically generate personalized teaching content and strategies through intelligent system inferences. The diagnosis mechanism is used to judge the learning level of students and provide a favorable basis for teachers to adjust teaching content. Based on the advancement of the current English teaching reform, the use of computer aid has become a trend in English teaching. It analyzes the current design requirements of computer aided English teaching systems and designs a teaching system based on C++ and Windows. The results prove that based on C++ and Windows, the design and realization of computer-assisted English teaching cannot increase the actual teaching efficiency by 20%, and can also play the value of computer-assisted English teaching, improve the level of English teaching by 12.0%. The conclusion shows that in the design of computer-assisted English teaching system, the design system based on C++ and Windows can effectively improve the quality of computer-assisted English teaching and have a positive impact..
A comprehensive index model for real estate convenience based on multi-source data
Authors: Hua Ling
Published: April 2021

The description information of the convenience of real estate is often qualitative and simple, and lacks comprehensive evaluation, so it is difficult to make horizontal comparison of the convenience of different real estate. Therefore, this paper proposes a comprehensive index model which uses multi-source data to measure the real estate convenience quantitatively. Based on the walking index, the model adds vector road network data, poi (point of interest) data and other multi-source data, and introduces the concept of walking score. Combined with the practical application of real estate, the model classifies the convenience facilities and calculates the walking distance between the convenience facilities and real estate quantitatively, so as to obtain a real number index to comprehensively measure the convenience of real estate. Finally, the experimental results based on Amap data prove the accuracy and effectiveness of the proposed model.
Arctic tundra shrubification: a review of mechanisms and impacts on ecosystem carbon balance
Authors: Mekonnen Zelalem A , Riley William J , Berner Logan T , Bouskill Nicholas J , Torn Margaret S , Iwahana Go , Breen Amy L , Myers-Smith Isla H , Criado Mariana García , Liu Yanlan , Euskirchen Eugénie S , Goetz Scott J , Mack Michelle C , Grant Robert F
Published: April 2021

Vegetation composition shifts, and in particular, shrub expansion across the Arctic tundra are some of the most important and widely observed responses of high-latitude ecosystems to rapid climate warming. These changes in vegetation potentially alter ecosystem carbon balances by affecting a complex set of soil–plant–atmosphere interactions. In this review, we synthesize the literature on (a) observed shrub expansion, (b) key climatic and environmental controls and mechanisms that affect shrub expansion, (c) impacts of shrub expansion on ecosystem carbon balance, and (d) research gaps and future directions to improve process representations in land models. A broad range of evidence, includingin-situobservations, warming experiments, and remotely sensed vegetation indices have shown increases in growth and abundance of woody plants, particularly tall deciduous shrubs, and advancing shrublines across the circumpolar Arctic. This recent shrub expansion is affected by several interacting factors including climate warming, accelerated nutrient cycling, changing disturbance regimes, and local variation in topography and hydrology. Under warmer conditions, tall deciduous shrubs can be more competitive than other plant functional types in tundra ecosystems because of their taller maximum canopy heights and often dense canopy structure. Competitive abilities of tall deciduous shrubs vs herbaceous plants are also controlled by variation in traits that affect carbon and nutrient investments and retention strategies in leaves, stems, and roots. Overall, shrub expansion may affect tundra carbon balances by enhancing ecosystem carbon uptake and altering ecosystem respiration, and through complex feedback mechanisms that affect snowpack dynamics, permafrost degradation, surface energy balance, and litter inputs. Observed and projected tall deciduous shrub expansion and the subsequent effects on surface energy and carbon balances may alter feedbacks to the climate system. Land models, including those integrated in Earth System Models, need to account for differences in plant traits that control competitive interactions to accurately predict decadal- to centennial-scale tundra vegetation and carbon dynamics.
Community Structure And Phytoplankton Abundance In Different Estuary In Coast Waters Lekok Pasuruan East Java
Authors: Herawati E. Y. , Darmawan A. , Azkiya M.
Published: April 2021

The quality of water in estuary is influenced by human activities around it which can affect the sustainability of the life of the organisms in these waters and other living things that use it. The aim is to analyze the abundance of phytoplankton and the quality of the waters of the river estuaries with different land uses for ponds, settlements and mangroves. This study was conducted by using survey method and carried out April - May 2020. The results of the abundance of phytoplankton in the coastal waters of Lekok as a whole are 3543 - 7692 cells / ml which are classified into mesotrophic waters. The phytoplankton with the highest abundance was dominated by Ceratium sp, indicating this species as an indicator of polluted waters. The results of water quality in Lekok coastal waters such as temperature, pH, salinity, DO and TOM are suitable for the life of phytoplankton organisms and in accordance with sea water quality standards. Water quality that exceeds the quality standard for nitrate, orthophosphate and TSS is due to the presence of nutrients or organic matter from human activities in different land uses that enter the waters and river estuaries.
Increasing Dissolved Oxygen in The Floating Net Cage Area of Jatiluhur Reservoir, Purwakarta
Authors: Zulkarnain R. , Adiyana K. , Waryanto  , Nugroho H.
Published: April 2021

Dissolved oxygen is one of the important parameters in fish farming in floating net cage in reservoirs or lakes. However, dissolved oxygen will decrease due to upwelling. In this study, an aerator trial was conducted in floating net cages in reservoir. The data obtained were analyzed descriptively and statistically. The results obtained show that the aerator can increase the level of dissolved oxygen in the floating net cage area with different magnitudes from 0.05 mg/L - 1.3 mg/L especially in especially at 4 and 5 m depths because output pipe length was 4 m for aeration.
Identification of Five Types Kampar River Fish With Genetic Approach
Authors: Fauzi M , Sumiarsih E , Hendrizal A
Published: April 2021

Fish identification in the mainland waters of Riau Province is generally carried out based on morphological characteristics. To identify fish species accurately in a short time, the DNA Barcoding method with a molecular approach is used. Five types of fish were taken from Kampar River and coded as MJ313, PJ36, SJ35, BJ33, and GJ41. The genes of these five fish were amplified, and PCR products were sequenced and analyzed using bioinformatics software. The editing of the sequencing results and the determination of the nucleotide composition were analyzed using Mega5 software. DNA sequences were aligned using the ClustalW software. The sequences obtained are then compared with GeneBank data using Basic Local Alignment Search Tools (BLAST). The results showed that the species with the code MJ313 and GJ41 were Channa striata, PJ36 were Osteochilus hasseltii, BJ33 were Mystus sp. Based on the sample examination, the species coded SJ35 cannot be determined because the marker band is low so that it is not visible. The results of the analysis on species coded SJ35 indicate that there is no COI report for species coded SJ35 on GeneBank.
Analysis of Water Quality in Layer Cage with Aquaponic System in PLTA Koto Panjang Container, Kampar District
Authors: Sumiarsih E
Published: April 2021

Aquaponies is one way to reduce water pollution produced by fish fanning, it can also be an alternative to reduce the amount of water used in the aquaculture system. Water quality is an important factor in fish fanning activities because it can affect the growth and development of fish cultivated in reservoir waters. The purpose of this study was to analyze the water quality of the KJA (floating net cages) layered with the aquaponic system tested in the waters of the Koto Panjang Hydroelectric Reservoir. Tins research was conducted in June - August 2020 at the Koto Panjang Hydroelectnc Reservoir. Measurement of water quality parameters is earned out directly at the research location. The analysis of the physical and chemical parameters of the waters is measured in the laboratory and the calculation of the water quality parameters refers to the APHA-AWWA and is compared with Government Regulation Number 82 of 2001 concerning Class II water quality standards. Based on the results of observations on water quality in layered cages with the aquaponies system, it is known that temperature parameters range from 31-33°C. pH ranges from 5-6. dissolved oxygen ranges from 9.38 - 9.65 mg / L. free carbon dioxide ranges from 9.14 - 11, 12 mg / L and brightness range from 148.9 to 156.2 cm. Meanwhile, nitrate parameters ranged from 0.03-0.04 mg L and phosphates ranged from 0.30 to 0.06 mg L. The water quality in the layered marine cage in the aquaponies system in the Koto Panjang Hydroelectric Reservoir has been able to reduce nitrate and phosphate content so that it can reduce the impact of organic pollution that occurs in the waters of the Koto Panjang Hydroelectric Reservoir.
The Use of SPOT 6 and RapidEye Imageries for Mangrove Mapping in the Kembung River, Bengkalis Island, Indonesia
Authors: Oktorini Y , Darlis V V , Wahidin N , Jhonnerie R
Published: April 2021

High-resolution satellite imageries believed to map the mangrove area well. Two satellite imageries with almost similar spatial resolution were expected to achieve this objective, including SPOT (Satellite Pour l’Observation de la Terre) 6 and a RapidEye. Two images covered the same area and acquired under the equivalent season at Kembung River, Bengkalis Island, Riau Province. A comparison was tested on several objectives. First, a comparison was conducted band by band through examining their statistical spectral analysis. RapidEye had a higher variance in all visible bands but low at NIR. Second, spectral separability using Jeffrey-Matusita distance was executed with three-band composites (SPOT 6/VNIR; RAPIDEYE/VNIR and RAPIDEYE/VNIR+RedEdge). SPOT 6 had better separability than RapidEye imageries compositions (VNIR+RedEdge and VNIR), with an overall accuracy of 79.9%, 75.3%, and 67.3%, respectively. Third, mangrove land cover classification. Three pixel-based classification rules were used, including a general classifier, maximum likelihood (ML), and two advanced classifiers, i.e., neural network (NN) and support vector machine (SVM). Results indicated that the use of SPOT 6 produced better overall accuracy than the other two image composition for each classifier. SVM was promising in the mangrove mapping algorithm compare to NN and ML.
The Effect of Administering Jeruju (Acanthus Ilicifolius) Leaf Extract on Blood Parameters of Tilapia (Oreochromis niloticus)
Authors: Rumondang  , Mulyani I , Sualang S M
Published: April 2021

This study was aimed to investigate the effect of various doses of jeruju leaf extract administered through feed on the blood parameters of tilapia, including erythrocyte count, leukocyte count, and differential leukocyte count and to determine the dose effectively affected the blood parameters of tilapia. Jeruju is a type of herbaceous plant or phytopharmaca which has the potential to enhance fish immunity. This plant is mostly found in coastal areas. The study was conducted from July to August 2018 in the Laboratory of Tanjung Balai Polytechnics (extract preparation), Blood Laboratory of Kisaran (blood examination) and Dusun IV in Pahang Village, Talawi Subdistrict, Batu Bara Regency (research location). The research method applied was the experimental method with Completely Randomized Design (CRD) consisted of four (4) treatments and six (6) replications, namely A (0 g/kg), B (8 g/kg), C (10 g/kg), and D (12 g/kg). The blood parameters of tilapia which included leukocyte count, erythrocyte count, and the percentage of lymphocytes, neutrophils, and monocytes were examined on the 0th, 7th and 14th day of the study. The administration of jeruju leaf extract resulted in a significant effect on leukocyte count, erythrocyte count, and lymphocyte percentage (P<0.05), but did not significantly affect the percentage of neutrophils and monocytes.
Fecundity and Eggs Diameter of Mullet Fish (Moolgarda perusii, Valenciennes, 1836) at Selotong Aquatic Langkat Regency, North Sumatera
Authors: Desrita  , Hutagalung S. , Onrizal  , Leiodonald R.
Published: April 2021

The aquatic area of the Selotong, Langkat Regency is an area with a good fisheries sector. Mullet fish is one of the caught fish in the Selotong. The purpose of this study was to determine the fecundity and the eggs’s diameter of Mullet fish (Moolgarda perusii). This research was conducted in July - September 2019 used gill net with 1.5 inch mesh size. Fecundity of Mullet fish (M. perusii) in GML III and IV ranges at 19.586 – 203.124 eggs with egg’s diameters ranging from 9,3-18,4 μm. Mullet fish (M. perusii) is a type of partial spawner.
Application of Principal Component Analysis to Characterize The Effect of Fishing Ground of Portunus pelagicus in Lancang Island Based on Environmental Parameters
Authors: Rahimah I. , Siregar E. S. Y. , Heriyanto T. , Siregar V. P.
Published: April 2021

Crab is a high economic value fishery commodity that is third after tuna and shrimp. crab production depends on natural fishing. In the use of crab resources, it is necessary to understand several factors. Quantitative ecological analysis can be use Principal Component Analysis. This analysis divides the parameter matrix into several components, then compiles the diversity of components collected from the largest at the turn of the main component. Spatial distribution of physical and chemical parameters is obtained by following the findings of catching the crab. This paper tries to understand the suggested environmental parameters for the success of crab life. Water quality sampling was taken on June 2015 (representing the eastern season), with an average range according to the following: SST 27.89°C - 29.39°C, TDS 28.05 - 29.60 g / L, TSS 0.004 - 0.161 mg / l, brightness 1.37 - 5.45 m, DO 5.09 - 9.17 mg / L, salinity 29.8 - 31.70 psu, phosphate 0.013 - 0.09 mg / L, nitrate 0,0009 - 0,5 mg / L, bathymetry 2.3 - 30 m. The fishing ground of crab is in grid B, C and D. On-grid B there are grids B1, B3, and B4. Then on-grid C there is on grid C3 and C4. On-grid D on the D6 grid. The results of the analysis of the correlation matrix of aquatic biophysical parameters show that the variance in the main components of the five main axes is 85.7%. Thus, the four main components can explain 85.7% of all information available on all parameters. The parameters that have the highest contribution are salinity, TSS, DO, brightness, nitrate, and sediment. The highest contribution indicates the influence of these parameters on the presence of crabs in the waters of Lancang Island and its surroundings.
Analysis of Production and Business Income of Gouramy (Osphronemus gouramy) Hatchery in Fifty Cities District West Sumatra Province
Authors: Hendrik  , Darwis A.N , Safputri M. A.
Published: April 2021

The research was carried out in Lima Puluh kota, West Sumatra Province, during March 2018. The purpose of this study was to analyze the efficiency use level of production factors, gouramy hatchery business farmer income, analysis of the BEP value of revenue, production and prices. The method used in this study was a survey method with a total sample of 36 farmers from a total of 126 farmers. Taking respondents using statified random sampling. Data analysis uses VPM / MFC ratio analysis, income analysis, and BEP analysis. The results showed that the use of urea fertilizer and feed production factors had exceeded the optimal conditions (efficiency value <1), while the production factors of the number of mother fish, manure, lime and labor were not optimal (efficiency value> 1). The average income is IDR 80,293,650 per year. The average BEP value of IDR 17,204,069, BEP production 9,271 tails, and BEP price of IDR 491, - / tail.
Sediment Distribution Model at Mesjid River Estuary in The Rupat Strait, Riau Province, Indonesia
Authors: Rifardi  , Mubarak  , Elizal  , Nurhuda A
Published: April 2021

The sediment transport model showing the sediment derived from the Mesjid River will be distributed to the Rupat Strait with different dispersion distances and concentrations depend on the tidal current pattern. The highest concentration of suspended sediment (0.0001 kg/m3- 0.0013 kg/m3) can be found at a distance of 3.3 km from the Mesjid River Estuary toward the Rupat Strait. Meanwhile, at a distance of 3.5 km from the estuary, the concentration have returned to normal or there is no longer any sediment derived from the Mesjid River. However, at a distance of 2.8 km to 3.3 km, or at the coordinates 101,372 - 101,376 North Latitude and 1,744 to 1,750 East Longitude, sediment deposition occurs with concentrations ranging from 0.00027 kg/m3to 0.00035 kg/m. Based on satellite images taken on August 2, 2006 and satellite images on January 5, 2020, sedimentation in the area has resulted in accretion with an area of ± 30,454 m2.
Determination of optimum animal feed raw material order allocation
Authors: Wahyuni D , Sembiring M T , Budiman I , Utari T , Silaen C D N
Published: April 2021

The availability of raw materials is the key to the implementation of production activities so that suppliers, who are able to supply according to the needs of the company, are needed. If the material that comes is not according to the specifications requested, even though the supplier changes so that the amount of material is still fulfilled, it still causes disruption to the smooth production process. The aim of this study is to assess the supplier’s performance to optimize allocated raw material. This research was conducted at an animal feed factory. The raw materials used include yellow corn and rice bran, obtained from several suppliers. The raw material that comes in part is rejected because it is not in accordance with the requested specifications, among others due to excessive water content, mushroom content and the content of corn cobs that exceed the established limit. In this study, carried out a performance analysis of suppliers referring to 23 supplier assessment criteria by Dickson and used 6 selected criteria, namely quality, delivery, history of supplier performance, claim and guarantee policies, prices and communication systems. The optimal amount of raw material orders from the results of goal programming is allocated to each supplier based on their performance.
Measurement of company productivity which experiencing material supply shortage
Authors: Budiman I , Sembiring M T , Nasution H
Published: April 2021

This research was conducted at a palm oil producing company in North Sumatra known as Sumatera Utara Province, Indonesia. This company has oil palm plantations, some of which have been converted to other businesses. This causes the production capacity that has been previously designed to be less effective in its use. This can be seen from the achievement of the target level of productivity. This research measured the level of productivity the company has achieved in the last two years using the Kendrick-Creamer Total Productivity Index Approach. The measurement results obtained over the past two years indicate that an increase in the total productivity index from 1.47 to 1.53. However, the increase has not been able to reach the productivity index target of 1.66. That was caused mainly by material, organizational, and installed capacity factors. The results obtained are selected alternatives for improvements to the sorting of materials, optimizing the production of his own garden, and maintaining screw press pressure with a total productivity index of 1.7.
The effect of education with audiovisual, booklet, and Whatsapp media on knowledge and attitude of fertile age in doing early detection of IVA test in Medan, North Sumatra
Authors: Imelda F , Santoso H , Raja S N L , Lunongga N
Published: April 2021

Cervical cancer becomes a cause of high maternal mortality. To prevent it can be done by screening Visual Inspection with Acetic Acid (IVA). The aim to analyze the effect of education applying the Health Belief Model using the audiovisual, booklet, WhatsApp media on knowledge and attitudes in conducting IVA examinations. The study used a quasi-experimental (two-group pre-post test without a control group). The sample were women of childbearing age who had never done an IVA examination before using purposive sampling with a sample size of 100 respondents, which were divided into 2 treatment groups, namely group 1 with audiovisual and booklets, and group 2 with WhatsApp. Health education used audiovisual, booklets and WhatsApp media. Data analyzed using a paired sample t-test. The results showed that there was an effect of education using audiovisual, booklets and WhatsApp media on the knowledge and attitude of early detection to do an IVA test. Increased knowledge, attitudes, health trust greater than before treatment. External variables such as age, education, occupation, income, prior information, and affordability of the IVA Test early detection site influence attitudes in improving behavior.
Evaluation of maize hybrids resistance to northern corn leaf blight in Karo Highland
Authors: Permana A , Hanafiah D S , Hasanuddin
Published: April 2021

Around two-thirds of corn area in North Sumatera are in high altitude places, where northern corn leaf blight limits yield. Evaluation was performed to 125 new hybrids for their resistance to northern corn leaf blight and yield components in Garingging, District of Karo, North Sumatera, from October 2019 to March 2020. Experiments were arranged in Augmented RCBD with 4 checks, Artificial inoculation was applied to ensure high and uniform disease pressure. Eight new hybrids exceeded at least 3 checks regarding to disease resistance and ear weight, namely N399, G163, N396, N374, D651, N020, D635, and N031. Hybrid N399 has ear weight above 4 checks and G163 has better AUDPC than the 4 checks, suggesting promising hybrids for developing varieties in areas with NCLB pressure. Significant association with AUDPC was seen in incubation period, ear diameter, ear length, and ear weight. High GCV was observed in disease resistance traits, while high heritability is estimated in incubation period, AUDPC, ear diameter, and ear length. Incubation period may be used in early selection.
Productivity and feed management strategies of sambar deer (Rusa unicolor) at the special purpose forest area (KHDTK) of Aek Nauli
Authors: Hutapea F J , Kuswanda W , Barus S P
Published: April 2021

The availability of feed plants is one of the most important components in improving the breeding ability of sambar deer in captivity. Planting program and productivity assessment of feed plants are necessary to ensure the availability of feed plants for deer, including deer management demonstration plot at Aek Nauli KHDTK. This study was aimed to observe the productivity and nutritional contents of sambar deer feed plants in Aek Nauli KHDTK. This study was performed at the deer feed plant plot. Sampling activities were conducted in the 1x1 m2 plot (for grass) and 2 x 2 m2 (for non-grass such as shrubs and herbs). The results showed that the productivity of 6 feed plants is about 51,56 kg day-1 (fresh weight) or 19,52 kg day-1 (dry weight); indicating that these plants meet the needs of 5 deer which are requiring 38.82 kg feed day-1. The average productivity of feed plants in the dominant dry days was about 33,342.75 kg ha-1 year-1 (fresh weight) or 14,977.17 kg ha-1 year-1 (dry weight). The productivity of feed plants in the dominant rainy days was about 60,687.33 kg ha-1 year-1 (fresh weight) or 20,287.92 kg ha-1 year-1 (dry weight). Nutritional contents of feed plants are water content (56.3-66.0%), protein (0.037-0.156%), ash content (5.891-7.199%), fat content (1.751-10.089%), and carbohydrate (21.597-33.932%). Required feed management strategies are regular weeding, block division, rotational harvesting system, fertilizing, watering (during the dry season), and providing additional feeds and supplements such as Pennisetum purpureum, Calliandra callothyrsus, Artocarpus heterophyllus, and Manihot utilissima.
Morphological characterization of soybean (Glycine max L. Merril) in drought stress condition and P fertilizer application
Authors: Siregar A O , Hanum C , Hanafiah D S
Published: April 2021

Drought stress in plants can occur due to an imbalance between the availability of water with the water needs of plants. Drought stress can cause morphological changes. This study aims to identify changes in the morphological character of soybean plants in drought stress conditions and P fertilizer application. This research was carried out at the screen house and laboratory of tissue culture of the Faculty of Agriculture, University of Sumatera Utara, Medan. This study uses a Completely Randomized Design (CRD) with 3 treatment factors. The first factor is the variety consists of 2 types, namely Devon 1 and Dering. The second factor is the field capacity of water content which consists of 3 levels, namely 80, 60 and 40% field capacity. The third factor is the application of P fertilizer consists of 5 levels, namely without P application, 1 recommended dosage of Rock phosphate, ½ recommended dosage of Rock phosphate, 1 recommended dosage of TSP and ½ recommended dosage of TSP. The results showed that drought stress treatment significantly reduced total leaf area (18.99%), root length (23.43%), root dry weight (16.67%) and crown dry weight (30.91%) when the available soil water content was reduced from 80% to 40% KL. Application of 1 dose of TSP resulted in the highest increase in root length, root dry weight and shoot dry weight compared to other treatments.
Profiling polyisoprenoids in kopasanda (Chromolaena odorata) stem barks and roots
Authors: Basyuni M , Fitri M A , Sumardi
Published: April 2021

Kopasanda (Chromolaena odorata (L.) R.M. Rob, Asteraceae) distributed in tropical and subtropical countries, including Indonesia. The kopasanda leaves contain several major compounds, such as tannins, phenols, flavonoids, saponins, and steroids. However, polyisoprenoids have no previously reported from this plant. This study aimed to determine the distribution of polyisoprenoid compounds in the bark and roots of the kopasanda plant. Total lipid on the kopasanda bark and roots was 61 and 48 mg/g dry weight. In comparison, the value of polyisoprenoid ranges from 11.8 and 27.3 mg/g dry weight. Results showed that polyisoprenoid compounds found in the roots were polyprenols and dolichols, regarded as type-II of polyisoprenoids. In contrast, in the bark of kopasanda, polyisoprenoid compounds a member of are a type I. Because dolichol dominated on bark, no plyprenols were detected. The present study confirmed the occurrence of polyisoprenoids in kopasanda roots and barks.
Determination of soil moisture reduction rate on peatlands in South Sumatera due to the 2019 extreme dry season
Authors: Irfan M , Koriyanti E , Awaluddin  , Ariani M , Sulaiman A , Iskandar I
Published: April 2021

The positive phenomenon of Indian Ocean Dipole (IOD +) in 2019 caused an extreme dry season in parts of Indonesia, including in the province of South Sumatera. This caused massive fires on peatlands in South Sumatera. The Government of Indonesia through the Agency for Peat Restoration (BRG) has deployed an integrated equipment system to measure in situ several fire control parameters on several peatlands, including in South Sumatera. The aim is to predict and mitigate fire incidents on peatlands. One of the measured parameters is soil moisture. This study has examined the impact of the extreme dry season on the rate of decline in soil moisture at four BRG measurement stations, namely: Cinta jaya-1, Cinta Jaya-2, Padang Sugihan-3, and Karang Agung. The rate of decrease in soil moisture (% per day) obtained were: 0.06, 0.31, 0.38, 0.47 respectively for the stations Cinta jaya-1, Cinta Jaya-2, Padang Sugihan-3, and Karang Agung.
Valuation of a man-made dipterocarp forest as seed source for Shorea red meranti (Dipterocarpaceae)
Authors: Rachmat H H , Pamoengkas P , Rahmatullah R K , Susilowati A
Published: April 2021

Lack of good quality seeds has been one of the constraints in icreasing the success rate of rehabilitation, restoration and establishment of plantation forest. Establishing seed sources is a way to increase the availability of qualified seeds for various purposes. Gunung Dahu Research Forest (GDRF) has Shorea pinanga and Shorea platyclados (Dipterocarpaceae) stands that has potential to meet the standard of identified seed stands (ISS). We evaluate two stands of S. pinanga (plot 05 and 24) and four stands of S. platyclados (plots 04, 15, 20, and 21e) to be quantified for their potential as ISS. Assessment was carried out by evaluating the parameters related to number of mother trees, accessibility, stand quality, management, fruiting history, and origin. Among all assessed plots, highest final score was obtained by plot 20 (131.5), followed by plot 24 (112.5), plot 05 (105.5), plot 04 (87), plot 21e (85), and plot 15 (57). Based on the minimum score of 94.5, the potential plot that can be assigned as ISS are plot 05, plot 24 and plot 20.
Physicochemical and sensory characteristics of brownies from composite flour (modified breadfruit, purple sweet potato, saga seeds, and mocaf)
Authors: Lubis D R K , Nurminah M , Nainggolan R J
Published: April 2021

Breadfruit is a plant that has potential as a national food security reserve because breadfruit is able to produce throughout the year, breadfruit is also a vegetable food ingredient that contains a lot of carbohydrates. Purple sweet potato can improve the taste of food processing products, because of its distinctive purple color, and high nutritional content. Saga seeds are high protein-producing plants concurrently increasing the nutritional value of food, and mocaf is the result of cassava fermentation by special enzymes that produce products that have characteristics such as wheat flour and have the potential as a food substitute for wheat flour. In this study, producing brownies from various composite flour to develop food diversity in Indonesia. The final results of the study showed that composite flour (modified breadfruit, purple sweet potato, saga seeds, and mocaf) with a ratio of 35%: 45%: 15%: 5% produced the best quality brownies in terms of hedonic values (taste, aroma, color, texture, general acceptance), water content, ash content, fat content, protein content, and fiber content.
Potential of lime as a green catalyst in the manufacture of furfural from Mikania micrantha
Authors: Iriany  , Taslim  , Bani O , Pratama A J
Published: April 2021

An attempt to increase the added value of lime has been done. The use of lime extract as a green catalyst in furfural manufacturing is expected to reduce the burden of pollution, and corrosion problems. This study aimed to evaluate the performance of lime extract as an organic acid catalyst in furfural production from Mikania micrantha (MM) through hydrolysis and dehydration and compare it with sulfuric acid catalyst. In this work, 50 g MM and 50 g dry NaCl powder were placed into a three neck flask equipped with a long condenser. The lime extract catalyst was added to the mixture at a ratio of 6:1 (v/w). The reaction temperature was varied from 100-120°C, and the condensed furfural was stored in an erlenmeyer as a function of time (0-330 min). Furfural was separated from water done by adding 50 ml chloroform to form two layers. The lower layer rich in furfural and chloroform was distilled at 70°C to evaporate chloroform. Purified furfural was identified using FTIR and GC-MS. The results obtained confirm that lime extract can be used as a green catalyst in furfural synthesis from MM.
Standardization and phytochemical screening of Centella asiatica, Moringa oleifera L. leaf and Spirulina sp. simplicia
Authors: Widyawati T , Syarifah S , Anggraini D R , Mustanti L F
Published: April 2021

Centella asiatica, Spirulina sp., Moringa oleifera have been used for traditional medicine. Studying the phytochemical constituents helps to reveal the usage of plants used as lead compounds for active pharmaceutical ingredients in commercial purposes. This study aims to determine the standardization and screening of phytochemicals from CA, ME and Spirulina. Standardization of CA, ME and spirulina showed as follows: total water 5.29 ± 1.1%; 5.98 ± 0.006% and 8.64 ± 1.16, total water soluble simplicia: 19.7± 0.57%; 10.97 ± 0.99 and 10.98 ± 1%, total ethanol soluble simplicia: 22.3 ± 0.57%; 15.99 ± 1.73% and 39.92 ± 1.73%, total ash: 23.11 ± 0.56%; 8.15 ± 0.28% and 8.65 ± 0.28%, total ash insoluble acid: 0.42 ± 0.07%; 2.15 ± 0.28% and 0.66 ± 0.28% respectively. Both simplicia of ME and spirulina contained of alkaloid, tannin, saponin, triterpene/steroid, flavonoid and glycoside whereas CA simplicia contained tannin, saponin, triterpene/steroid, flavonoid and glycoside.
Artocarpus heterophyllus leaves extract improve facial skin in clay mask formulation
Authors: Widyawati T , Syarifah S , Nufus H
Published: April 2021

Artocarpus heterophyllus (A.heterophyllus) is one of plants that commonly used for skin care. This study aimed to formulate a clay mask preparation with the active ingredient A.heterophyllus 3% leaf extract and evaluating its activities in repairing facial moisture, smoothness, large pores, blemishes and wrinkles. The process of providing clay masks begins with the preparation of Artocarpus heterophyllus leaf etanol extracts with standardized quality, preparation of clay mask bases with guaranteed quality, mixing clay mask bases with extracts, testing the quality and stability and effectiveness of skin care tested. The extract of clay mask formulations were stable in storage, homogeneous, pH 5.6-6.3; drying time is 10-18 minutes, and does not irritate. Effectiveness testing was performed using a skin analyzer for 4 weeks of treatment in adult female volunteers. Test results after 4 weeks of treatment showed that the ethanol extract of A. heterophyllus leaves 3% was able to improve moisture (15.5%), smoothness (33.1%), pore size (60.1%), blemishes (50.2%) and facial wrinkles (61.5%). Statistically, significant effects were found in moisture and smoothnes of the facial skin (p < 0.05). This study concluded that ethanol extract of A. heterophyllus in concentration of 3% have benefit in refining facial skin.