bluuebunny/crossref_metadata_2025 huggingface dataset:
Delineation of the new site of ngempon temple in ngempon village, bergas district, semarang regency using the microtremor method
Authors: Ubaidillah M A , Yuliyanto G , Irham M N
Published: June 2020

Ngempon Temple was discovered below the ground level caused by collapsed land in 1952 in Ngempon Village, Bergas Sub-district, Semarang Regency. The HVSR method is used in the three-component microtremor to identify the bedrock response frequency. Additionally, this method can be used to determine the dominant resonance frequency (f0) and the peak value of HVSR (A), which shows the dynamic characteristics of sediments. This study aims to determine the position and types of archaeological objects that are still hidden and make a modeling of the subsurface conditions. The method used in this study is a trapezoidal measurement geometry by measuring spaces within 2 meters. Data retrieval duration is 10 minutes for each point, and the specified frequency sampling is 10 Hz. The H/V curve generated from data processing will result in the frequency value and amplification that will be analyzed and linked to the Ngempon Temple archaeological data. The results obtained from this study indicate the existence of the temple’s fundamental rocks and rock debris model below the surface indicated by the contours of the HVSR spectrum profile. They are an amplification value of 1.3 and the response frequency with a sensitivity of up to 4 Hz from the surface, and an amplification value of 1.3 and the response frequency with a sensitivity of 5.8-10 Hz. The sensitivity to measurements is based on whether the response passes the excavation of BPCB Central Java. If it passes, then the response indicates an anomaly of the fundamental rocks. Vice versa, if the measurement does not pass the object of research, the response only shows the existence of temple rocks fragments. The amplification value and frequency of response shows a difference between the temple rock and the sediments above it.
Burnup computation for HTR-10 using MCNPX as the function of radius and fuel enrichment
Authors: Setiawati E , Juliawan S , Arianto F , Margiantono A
Published: June 2020

The HTR-10 is a gas-cooled high-temperature reactor with spherical fuel and moderator called pebble bed and operated on 10 MW thermal power. Until now, a lot of research and development on the HTR-10 in terms of neutronic computational modeling has been carried out, one of which is burnup analysis. Fuel depletion or burnup analysis is an analysis related to fuel control and reactor output power. This analysis is needed because changes in fuel composition will affect the neutronic parameter values of a reactor. The 10 MW HTR fuel depletion study has been conducted by modeling the reactor using MCNPX (Monte Carlo N-Particle e-Xtended) to analyze the effect of radius and enrichment of reactor fuel to the left value and the burnup rate. The study is conducted by modeling a 10 MW HTR with three sorts of fuel kernel radiuses using MCNPX. First, 250 μm radius, second, 275 μm radius, third, 300 μm radius and all radiuses are variated with 10-15% fuel enrichment. TRISO particles are dispersed using simple cubic (SC) lattice in the fuel zone. The fuel balls are allocated in the reactor core along with moderator balls using a body-centered cubic. To perform all the calculations, MCNPX utilizes continuous energy data library ENDF/B-VI. From the calculation result using MCNPX can be concluded that the kernels with the radius of 275 μm and 300 μm at 14% and 13% fuel enrichment respectively were more able to maintain a critical condition within a year of operation than the kernels a 250 μm radius and the fuel with 250 μm radius has the highest burnup rate that is 52,07 GWd/MTU.
Development of electrooptic devices by strengthening electromagnetic fields using colloidal silver solutions
Authors: Sugito H , Khumaeni A , Firdausi K S , Azam M
Published: June 2020

The development of electrooptic devices by strengthening the electromagnetic fields using colloidal silver has been carried out. This tool works based on the electrooptics method. The samples used were aquabides and a solution of aquabides mixed with colloidal silver with various concentrations. The light source used is a green laser with a wavelength of 532 ± 10 nm. Measurements are made by observing changes in the natural polarization angle and the electro-optical polarization angle. The test results show that at a concentration of 0-0.25 there is a significant change in the polarization angle to the increase in the external electric field (0-9 kV). While at a concentration of 2.5-1 there is a tendency that there is no change in the polarization angle.
Effects of repetition rate on the identification of elements in gemstone using the LIBS method
Authors: Bagaskara A , Soesanto Q M B , Sugito H , Khumaeni A
Published: June 2020

In material science, there are several methods for detecting elemental content in a material (sample) such as X-Ray Fluorescence (XRF), (X-Ray Diffraction) XRD, (Scanning Electron Microscope) SEM, (Transmission Electron Microscope) TEM), etc. Non-metallic samples such as gemstone can be detected by XRF and XRD methods. But in this method, the sample must get special treatment such as being crushed and converted into powder form. In this study, LIBS was used to identify elements in a gemstone. The laser-induced breakdown spectroscopy (LIBS) method is an alternative method for solving deficiencies in the previous study. The results show the same elements contained in the gemstone can clearly be detected. The elements are also confirmed by using the standard technique of X-ray fluorescence and the result revealed that the elements are consistent as in the case of the LIBS technique.
Analysis of signal to noise ratio from 1.5 tesla MRI head coil phantom image on daily quality assurance
Authors: Maslebu G , Kusrini E S D , Setiawan A
Published: June 2020

Signal to Noise Ratio (SNR) is one of the quality control tests for most diagnostic imaging modality, including Magnetic Resonance Imaging (MRI). This study used MRI 1.5T GE Signa Creator type and head coil phantom with variations of Echo Time (TE), Repetition Time (TR), voxel volume and flip angle. 16 data images were obtained from the acquisition process. These images were analyzed using image processing software to calculate the SNR value. It results in four data distribution with the highest value of 36.98 and the lowest value of 32.64. The graphs of voxel volume versus SNR also formed four groups of data with an overall value above SNR baseline value for daily operation.
Fabrication and properties of high efficiency dye-sensitized solar cells (DSSCs) with photon absorption optimization
Authors: Suseno J E , Wardaya A Y , Khumaeni A
Published: June 2020

Dye-sensitized solar cells (DSSCs) have attracted much attention because these unconventional solar cells exhibit high performance and have the potential for low-cost production. To achieve higher performances for solar cells based on organic dyes, comparable to those for solar cells based on the color spectrum, the light absorption of organic dyes is required. In a DSSC, the electrodes are surrounded by a thin shell and a dye monolayer for 3 colors of dyes. Based on the optical properties, the large absorption of light can be given in a colorless dye with a wavelength of the most extensive. Combination colors from three-band basic colors, such as red (R), green (G) and blue (B) can create the optimum light absorption. The Incident Photon-to-charge Carrier Efficiency (IPCE) will be high if the absorption spectrum graph of dye color is large too, therefore the Dye-Sensitized Solar Cell (DSSC) will produce photon current (If) or high short-circuit current (Isc). To ensure solid surface coverage, the dye must have a high absorption coefficient on TiO2. The electrodes can be maximized with reduced layer thickness so the possibility of recombination decreases with decreasing electrode thickness and thicker electrolytes with low vapor pressure can be applied. The longer the wavelength, the less absorption will cause a small portion of the sun’s spectrum to disappear. The experiment showed that a combination of three band colors of dye is obtained the largest light absorption. This black color proved to have the greatest light absorption. The experiment can result for the exhibit a high open-circuit voltage VOC of 320 mV, open-circuit current IOC of 0.045 mA, maximum voltage Vmax of 134 mV, maximum current Imax of 0.044 mA, maximum power Pmax of 5.89 μW, Fill Factor (FF) of 42 and a power conversion efficiency of 9.1%.
K-nearest neighbor (KNN) with global GINI diversity index for classification subsidy food in Semarang city, Indonesia
Authors: Ispriyanti D , Prahutama A , Mustafid
Published: June 2020

K-Nearest Neighbor (K-NN) is one of the classification methods using the distance from the variable. Determination of the distance used greatly affects the results of the classification. The distance commonly used as a weighting is the Euclidean distance. The Euclidean distance does not distinguish between categories and variables, this is certainly a problem in itself. Therefore the weighting used is the global GINI diversity index. This method will be applied to the classification of subsidy food in Semarang city, based on the factors that influence it. Independent variables that are used include the field of business of household heads (X1); Employment Status (X2); Homeownership status (X3); Roof Building Materials (X4); Main wall material of the house (X5); Main Material of the house floor (X6); Drinking Water Source (X7) and Main Cooking Fuel (X8). Based on the results of classification using the KNN method with a global weighting GINI diversity index, with training: testing is 80: 20 obtained an accuracy of 85% with a value of K = 5.
Hoax news validation using similarity algorithms
Authors: Yuliani S Y , Sahib S , Abdollah M F , Wijaya Y S , Yusoff N H M
Published: June 2020

News that is presented every day on social media dramatically affects the feelings, feelings, thoughts, or even actions of a person or group. Hoax News is one of them which is disturbing the public and raising noise in various fields, ranging from politics, culture, security, and order, to the economy. Inseparable from social media users. How every day, there is information on social media, which is not necessarily true so that people are provoked by hoax on social media. The news detection system in this study was designed using Unsupported Learning so that it does not require data training. The system was built using the Equation algorithm to calculate the validity of document similarity. Extraction results used to search for content related to user input using a detection engine, then the similarity value and the time needed to utilize hoax news are calculated. System validation testing by using a four text similarity algorithm called the Equation algorithm, the Levenshtein algorithm, the Smith-Waterman algorithm, the Damerau Levenshtein algorithm; this algorithm is used to find the best analytical solution of news hoaxes and submissions needed to find the news hoax password. The final results of the deception detection research using a script that has been done for Validation using an algorithm, get the value of accuracy in detection using the Smith-Waterman algorithm, which produces an accuracy value of text similarity of 99.29% and can be used a process of 6, 57 seconds, followed by the second sequence that is the similarity algorithm produces an accuracy of 75% and requires a processing time of 4.94 seconds, then the third sequence is the Levenshtein algorithm with an accuracy of 55.02% and requires a processing time of 5.49 seconds, and is used today is Damerau Levenshtein algorithm is 55.02% and requires a processing time of 7.54%. The results of research tests on this text can conclude the more text on the detection engine, the higher the verification value and the higher the time needed to process hoax news.
Rice crop management expert system with forwarding chaining method and certainty factor
Authors: Kharisma  , Adi K , Isnanto R R
Published: June 2020

Rice plants are one of the focuses on food sustainability so that an increase in rice production needs to be done. Farmers need information and knowledge to improve rice crop production by practicing good planting methods that begin with the selection of superior varieties of seeds and handling plant pests properly. The problem that arises is that assistance from agricultural specialists is not always available when farmers need it, making it difficult for farmers to consult experts according to their needs at any time. Therefore, in this study, an expert system was proposed which was able to help farmers to obtain information according to their needs. This research builds an expert system for the management of rice plants including the selection of rice seed varieties and handling pests of rice plants. The method used in this expert system is forward chaining and certainty factor. Knowledgebase data was obtained from experts in agricultural extension, experts on plant pest organisms and literature from the agricultural service. From this study, an expert system was produced that was able to provide information on the selection of seed varieties and pest of rice plants according to the conditions and needs of the users.
Γ – semigroup generated by a semigroup
Authors: Sumanto Y D , Aziz A , Solikhin  , Hariyanto S
Published: June 2020

In Γ – semigroup S, the element of Γ maybe a binary operation in S. Every element of any semigroupS can define a binary operation in S. A collection of binary operations defined of the element of S generates Γ – semigroup S.
An analytic solution of the uncoupled multi-agent model and its benefit through optimal control system with attractor and repellant
Authors: Tjahjana R H
Published: June 2020

This paper gives the analytic solution of the uncoupled multi-agent model. This solution describes the optimal path of each agent. In this exposition, the optimal control approach is used to model uncoupled multi-agent swarm with attractor and repellant. The special functional cost contains repellent cost functional is used to guarantee each agent never collides one to the others. The attractor term in the special functional cost makes each agent never mover far away to the others. This paper also gives the benefit of the agents moves in the multi-agent system.
WAC4 algorithm to solve the multiperiod degree constrained minimum spanning tree problem
Authors: Wamiliana  , Junaidi A , Amanto  , Usman M , Warsono
Published: June 2020

The Multiperiod Degree Constrained Minimum Spanning Tree (MPDCMST) is a problem of finding the smallest weight spanning tree while also maintaining the degree restriction in every vertex and satisfying the vertex installation requirement in every period. This problem arises in the networks installation problem where the degree restriction represents the reliability of each vertex and the vertex installation requirement represents the priority vertices that must be installed in the network on a certain period. The installation is divided into some periods because some conditions occur such as harsh weather, fund limitation, etc. In this paper, we propose a WAC4 Algorithm to solve the MPDCMST problem. The performance of the algorithm will be compared to the WAC1 algorithm already in the literature.
Counting the number of vertexes labeled connected graphs of order five with minimum five edges and maximum ten parallel edges
Authors: Amanto  , Notiragayu  , Puri F C , Antoni Y , Wamiliana
Published: June 2020

If given a graph G(V,E) with n vertices and m edges many graphs can be constructed. The graphs constructed maybe connected graphs (there exists at least one path connecting every pair of vertices in the graph) or disconnected; either simple a (contains loop or parallel edges) or not simple. In, this paper we will discuss the formula for counting the number of connected vertex labelled graph of order five (n=5) without loops, witof h minimum five edges and maa y contaiof n maximum ten parallel edges.
Forecasting the number of airplane passengers uses the double and the triple exponential smoothing method
Authors: Ramadiani  , Syahrani R , Astuti I F , Azainil
Published: June 2020

Forecasting is needed to increase capacity and infrastructure, and also to improve the quality and quantity of the airport, especially at Aji Pangeran Tumenggung Pranoto Samarinda’s airport. The forecasting method is very diverse. It is difficult to forecast the number of passengers in each period. This is very important to compare the accuracy of the forecasting number of passengers and how to find out the best method to produce the forecasting value. This research uses the mean square error to measure the accuracy of double exponential smoothing and the triple exponential smoothing. The results of this research found the accuracy level between double exponential smoothing and triple exponential smoothing that produced the best forecasting value. MSE error calculation uses alpha constant values 0.1, 0.3, 0.5, 0.7 and 0.9. The best result is the double exponential smoothing method of alpha value 0.9 with an error value of 20522138,748.
Stability analysis of mathematical model (sirb) in the spread of cholera with vaccination and disinfection
Authors: Fitriyani A , Widowati  , Farikhin
Published: June 2020

Cholera is a disease as a kind of acute diarrhea caused by bacteria V. Cholerae. The spread of cholera can be modeled in the form of nonlinear differential equation systems with 4 variables SIRB. This paper aims to research to analyze the local stability of the equilibrium point of the dynamical population in the spread of cholera by the Routh-Hurwitz stability criterion and bifurcation method. Next Generation Matrix (NGM) method is used to get the basic reproductive numbers ( ℜ0 ) to find the local stability at the equilibrium point of the. The disease-free equilibrium point is locally asymptotically stable if ℜ0 < 1, while the endemic equilibrium point is locally asymptotically stable if ℜ0 > 1 the results of numerical simulations obtained ℜ0 = 0 0.87 indicated that the disease-free equilibrium point is locally asymptotically stable. In endemic condition ( ℜ0 > 1 ) show that increasing the rate of vaccination and disinfection can reduce the population of susceptible, infected and bacteria of V. Cholerae.
Secondary metabolites in elaeocarpus grandiflorus cell culture in WPM medium with various concentrations of PGR
Authors: Anggraito Y U , Nugrahaningsih W H , Musafa F , Mukhtar K , Wijawati  , Rostriana Y , Safitri  , Habibah N A
Published: June 2020

This study aims to analyze the influence of plant growth regulator (PGR) for secondary metabolites production in Elaeocarpus grandiflorus cell culture. Picloram (3.5, 5 and 7.5 ppm) and 2,4-D (1.5, 2.5 and 3.5 ppm) were used as PGR of cell suspension culture. Cell cultures were obtained from callus grown in liquid WPM medium with various concentrations of PGR. Culture is maintained in shakers at a speed of 120 rpm in dark conditions. Harvesting is done after the age of culture reaches 30 days. Extraction was done by the maceration method with methanol as a solvent. A qualitative test using a thin layer chromatography test (TLC) was conducted to analyze the presence of various secondary metabolites. Phenolic quantitative tests were performed using a spectrophotometer using gallic acid standard compounds. The results showed that the cell culture contained alkaloids, phenolics, terpenoids, flavonoids. All treatments showed the presence of phenolic with varying total phenolic concentrations. PGR affects the type and concentration of secondary metabolites produced by E. grandiflorus cell suspension culture.
The impact of mangrove plantation in ponds on the secondary metabolite content
Authors: Hastuti E D , Izzati M , Darmanti S
Published: June 2020

Planting of mangrove vegetation integratively in silvofishery pond alters the possibility of metabolite accumulation pattern. This research aimed to analyze the metabolite content in mangrove root and leaf ofAvicennia marina, to analyze the difference of metabolite content between pond and shore area, and to analyze the correlation of metabolite content between the root and the leaf. The research was carried out through field sampling in Mangunharjo Village followed by laboratory analysis for alkaloid, phenol and terpenoid content. Samples were taken fromA. marinaroot and leaf planted in the pond and shore areas by triplication. Data analysis were including t-test and correlation. The result showed that total alkaloid and total phenol content was varied between growing location. Significant differences between pond and shore mangrove metabolites were obtained for total alkaloid content in the root and total phenol content in the leaf. Correlation analysis between root and leaf metabolite contents showed its significance for total phenol content in the pond area. The research implied that mangrove in pond area underwent higher environmental stress compared to the ones in shore area.
The production of alkaline protease from Aspergillus flavus DUCC K225 on rice bran containing medium
Authors: Rukmi I , Purwantisari S
Published: June 2020

Alkaline protease is an industrially important enzyme that can produce by Aspergillus flavus DUCC K225 an indigenous mold from lime soil Madura island. The production of alkaline protease by Aspergillus flavus DUCC K225 produced by submerged fermentation on modified Czapeks Dox medium containing rice bran as N source. The enzyme production was observed after 7th-day incubation, by measuring the protease activity at pH 8.5 and the temperature stability as well. The results showed that the enzyme activity is higher on the rice bran medium compared to the standard medium, with a value of 237,84 U/ml and 94.85 U/ml respectively. This alkaline protease enzyme produced also thermostable, with 89.3% stability value for 60 min at 40°C.
Histologic response of aortic Rattus norvegicus male strain wistar hyperlipidemia after giving kersen fruits juice and extract lakum leaves
Authors: Agustina E , Saraswati T R , Tana S
Published: June 2020

People lifestyle who tend to consume high fat diet is one of the risk factors causing cardiovascular diseases such as atherosclerosis and coronary heart disease. The aims of this study were to analyze the effect of kersenfruits juice and extract lakum leaves on lumen width and thickness of aortic wall and to find out the histological features of male Rattusnorvegicus white rats due to hiperlipemia. The study used a Completely Randomized Design (CRD) consisting of 5 treatments with 4 replications, i.e. the control group (P0), the standard feeding group (P1), the hyperlipid feed group+0.2 mL/200gBB kersen juice (P2), the hyperlipid feed group+40mg / 200gBB extract lakum leaves (P3) and hyperlipid feed group +0.18mg / 200gBB simvastatin (P4). Hyperlipid feeds were given for 28 days. Data were analyzed by ANOVA followed by Duncan Test at a confidence level of 95, while histological features were observed directly using photomicrograph with 400x magnification and were seen aortic lumen narrowing, foam cells and intracellular lipid accumulation in smooth muscle. The results showed that the addition of kersenfruits juice and extract lakum leaves gave a significant effect on lumen width and thickness of the aortic wall (p <0.05). Histological features show the presence of foam cells and accumulation of smooth muscle lipids in the control and group treatments with hyperlipemia feeding. The conclusion of this study is that the addition of kersen juice fruits and extract lakum leaves can reduce atherosclerotic lesions by eliminating foam cells and proliferating smooth muscle cells so the size of the aortic lumen width returns to normal.
Antibacterial activity of basil oil (Ocimum basilicum L) and basil oil nanoemulsion
Authors: Fachriyah E , Wibawa P J , Awaliyah A
Published: June 2020

Basil oil contains bioactive compounds with antibacterial activity. One way to increase the antibacterial activity of basil oil is to use a nanoemulsion design. This study aims to obtain a nanoemulsion of basil oil with the best antibacterial activity against Escherichia coli and Staphylococcus aureus compared to basil oil. Process isolation of basil oils uses the method of steam distillation. The nanoemulsion process uses the ultrasound method. The essential oils and nanoemulsions produced were analyzed by GC-MS. The five components of basil oils with the largest percent area are sabinene (60,01%), myrcene (17,76%), trans-caryophyllene (4,08%), linalool (2,58%), and alpha-pellandrene (2,35%). Whereas in nanoemulsion are sabinene (44,68%), myrcene (17,86%), trans-caryophyllene (8,15%), terpineol-4 (6,65%), and 1.6-octadient-3-ol 3,7-dimethyl (4,89%). The basil oil has a droplet size of 54960 nm while the nanoemulsion of basil oil has a droplet size of 243.4 nm. The concentration of basil oil influences the antibacterial activity. The essential oil of basil, at a concentration of 10% to 25%, has a zone of low to medium protein inhibition at E. coli and is strongly directed towards S. aureus. The nanoemulsion of essential oils at a concentration of 5% to 25% has a moderate to strong inhibition zone in E. coli and a moderate to a very strong group in S. aureus.
The potency of B-G31 isolate associating with valanganigricornis as a probiotic candidate to digest cellulose
Authors: Abdullah R , Imtiyaz F D , Wijanarka  , Nurhayati
Published: June 2020

Cellulose is a polymer that is abundant in the environment, but they are unable to digest by the human digestive system. This study aims to determine the anti-pathogenic ability and measure the cellulase activity of B-G31 isolate. Auto-aggregation and co-aggregation methods were used to analyze the anti-pathogenic role of B-G31 against biofilm formed by Escherichia coli and Staphylococcus aureus. To assess glucose concentration obtained from cellulose degradation, B-G31 supernatant was reacted in different CMC concentrations (0.5%, 1%, 1.5%, 2%, and 2.5%) and was measured their absorbance (OD540) using ELISA spectrophotometer. The study has revealed that the percentage of B-G31 auto-aggregation is 26% and they can explicitly inhibit colonization of E. coli and S. aureus biofilm accounted for 20.21% and 21.20%, respectively, the bacteria also exhibited antagonistic activity towards two bacterial pathogens. Furthermore, enzyme activity was relatively high in the presence of 2% CMC with 0.913 U/mL to yield average glucose of 411.75 ppm and significantly different from that in the control group (p < 0.05). However, the enzyme value in 0.5% CMC concentration was about 0.345 U/mL and not significantly different from control group (p > 0.05). Our results indicated that B-G31 isolated from Valanganigricornis can form aggregates against bacterial-tests biofilm and increase degradation of cellulose, thus, the isolate could probably be used as probiotics to digest cellulose.
Isolation and identification of rare actinomycete-like bacteria from soil-based on 16S ribosomal RNA gene sequences
Authors: Eshananda Y , Ningsih F , Sakai Y , Yokota A , Yabe S , Sjamsuridzal W
Published: June 2020

The rare actinomycete-like bacteria are mycelium-forming bacteria other than phylum Actinobacteria that difficult to isolate and cultivate. This group of bacteria was recently speculated by many scientists as a potential new microbial resource for the discovery of novel compounds, as a substitute for actinomycetes. In this study, we isolate and identify rare actinomycete-like bacteria from forest soil collected under bamboo trees, near the CisolokGeysers, Sukabumi, Indonesia. The isolation of bacteria was performed using Reasoner’s 2A (1:10 dilution) medium with 2% gellan gum instead of agar and incubated at 30 °C for three weeks. The 16S rRNA gene sequences of the isolates were examined to determine their taxonomic position. Four isolates designated K17-1, K17-2, K42, and K44 showed pale oranges colonies and formed mycelia were obtained. The results of 16S rRNA gene sequences of these isolates showed high similarity to members of the genus Dictyobacter in the family Dictyobacteraceae of the class Ktedonobacteria of the phylum Chlorofexi, with values 97.16-98.02%, and most closely related to the species Dictyobacteraurantiacus S-27T (97.16-98.02% similarities). This result suggested that the member of the class Ktedonobacteria, which considered as rare actinomycete-like bacteria, such as Dictyobacter could be found in the forest soil of the geothermal area.
The control system for the nutrition concentration of hydroponic using web server
Authors: Suseno J E , Munandar M F , Priyono A S
Published: June 2020

This research was conducted to realize a nutrient solution concentration control system using web interface monitoring. The hydroponic system only relies on nutrient solutions whose nutrient levels must be maintained to anticipate the increase in acidic acid levels of the nutrient solutions. The provision of monitoring and recording changes in hydroponic system nutrition is very helpful in maintaining the quality of hydroponic agricultural production. The provision of data from electrical power measurements needs to be supported by information technology, especially remote data measurement technology. This remote data monitoring uses a wireless network system using a TDS (Total Dissolved Solids) sensor, Arduino DUE microcontroller, WiFi module and internet connection for the observation process. The TDS sensor used previously was characterized and calibrated. The data obtained by the sensor is used to exercise control before sending it to the thingspeak.com channel to be recorded and displayed in realtime. In testing the sensor TDS meter error of 2.88%. The results of the test for 2 hours obtained the results of the control system can increase the nutritional PPM from 213 PPM to 451 PPM within 30 seconds with a nutrient enhancer sample of 779 PPM, and decrease from 779 PPM to 431 PPM within 70 seconds with a water-enhancing sample of 213 PPM for the 445 PPM set point. In the second test result for 2 hours, the control system results can increase the nutritional PPM from 215 PPM to 814 PPM within 30 seconds with a nutrient enhancer sample of 956 PPM, and decrease from 956 PPM to 754 PPM within 40 seconds with a water-enhancing sample of 215 PPM for the 780 PPM set point. PPM value of nutrients can be affected by the presence of other solids such as sand which dissolves with water.
Bioethanol production using the SSF method (simultaneous saccharification and fermentation) of microalgae anabaena sp.
Authors: Permatasari N S , Zainuri M , Kusumaningrum H P , Mishbach I , Hastuti E D
Published: June 2020

Bioethanol is one of the alternative energy sources that answer the current energy crisis problems. The advantage of bioethanol compared to the fuel oil (BBM) is biodegradable. It contains an octane and high oxygen so it is flammable and reducing global warming emissions. Recently, the main ingredient of bioethanol has entered the third generation which is using microalgae. Anabaena sp. is one of the microalgae types from cyanobacteria which has the advantage of being used as bioethanol because it has carbohydrate biomass of about 20-30%. This research is aimed to produce bioethanol from microalgae Anabaena sp. The bioethanol production method used SSF because the advantage showed the converted polysaccharides into monosaccharides did not return to polysaccharides. It was caused monosaccharides directly fermented into ethanol. The use of one reactor reduced the cost of the process in the equipment used. This research was conducted in several stages, namely the preparation of raw materials, acid hydrolysis using H2SO4 1 M, and fermentation with the help of Saccharomyces cerevisiae microorganisms anaerobically. The results showed that using the SSF method was able to produce ethanol levels of 7%.
Morphotypes and molecular characterisation of pink pigmented bacterial symbiont of Turbinaria sp.
Authors: Lunggani A T , Kusdiyantini E , Imtiyaz F D
Published: June 2020

Turbinaria sp. is one of the species of the brown algae class that has extraordinary prospects for human health. The potential of the brown algae makes it a target for the search for sources of beneficial bioactive compounds in the pharmaceutical world. However, a serious problem in the development of bioactive compounds from these biotas is the problem of supply, because to obtain a relatively small number of active compounds requires a large number of marine organisms. It was reported that there are associations of microorganisms with brown algae which are thought to synthesize secondary metabolites such as the host organism. The presence of bacteria that is symbiotic with brown algae has made it possible to use these organisms as the main source of bioactive compounds from the marine. KRT-7 isolate is a pink bacterial isolate from the Turbinaria sp. collected from Menjangan Kecil, Karimunjawa Island, Indonesia. This isolate has been known to produce bio pigment and genes coding for its bioactive compounds. However, the physiological morpho character and its molecular identity are unknown. The study aims to determine the morphophysiological character and molecular identification of the prospective isolates. The research results obtained will contribute a scientific finding of the prospect of genetic diversity of Indonesian marine bacterial isolates and their corridor utilization as a source of bioactive compounds.
Molecular identification and antioxidant test of Chaetoceros sp. from Gondol, Bali
Authors: Susetyo M A , Kusumaningrum H P , Jannah S N , Abdullah R
Published: June 2020

Chaetoceros is one of the largest genera of microalgae that has more than 400 species and it is the primary producer in the marine ecosystem. Chaetoceros sp. has some of the pigment which is very important for their survival including chlorophyll and carotenoid pigments. This study aims to identify Chaetoceros sp. from Gondol Bali using ITS fragments, to understand its phylogenetic relationship between microalgae-based on their antioxidant activity. The results of ITS fragments identification and antioxidant activity of Chaetoceros sp. will be used to develop further research related to its potency. The method for microalgae DNA isolation was conducted using the Doyle and Doyle method following with amplification using ITS4 and ITS5 primer. Then, the sequences will be analyzed. The antioxidant activity will be performed by the DPPH method. The results of DNA isolation showed the concentration and purity for about 2842.1 ng / µl and1.97 respectively. PCR products from the amplification of the ITS fragment produced 882 bp. Phylogenetic analysis revealed that Chaetoceros sp. from Gondol Bali had a close relationship with C. muelleri KF 998567.1 and the antioxidant activity test showed IC50 values were about 72,386 ppm.
Potential of phytotechnology in wastewater treatments to produce alternative electrical energy: a review
Authors: Zaman B , Samadikun B P , Budihardjo M A , Hardyanti N , Rachma A F , Hasna S I
Published: June 2020

Recently, phytotechnology has gained much attention due to its capability in treating wastewater by biological processes. Phytotechnology is the application of science and engineering to examine environmental problems and provide solutions by the direct use of plants for in situ removal or degradation of contaminants or improving environmental function and quality. This process using bacteria formed in the roots of the plant and it can be applied to treat the wastewater. In this phytotechnology process, it presents the potential for energy generation and comprehensive wastewater treatment in Microbial Fuel Cell (MFC) system, which in the process utilizes bacteria that can produce alternative electrical energy because of the activity of bacteria which can self-mediate electrons to the anode through contact between the membrane-anode. MFC are expected to be applied to energy-saving wastewater treatments (WWT). The combined of MFC and phytotechnology system have function to degrade organic compunds and remove contaminant contained in wastewater to produce bacterias that come out in the roots and then the bacterias will be used by electrodes to produce electricity. This paper will analyze the advantage and disadvantages of phytotechnology system while used to produce electrical energy by MFC system as hybrid system. Based on the existing research, show that phytotechnology has a lot of advantages. One of the advantages is promising low cost, highly efficient, and renewable energy-producing alternative to conventional wastewater treatments.
Effects of percent weight of divinylbenzene as crosslinking agent on the properties of eugenol–divinylbenzene copolymers
Authors: Prasetya N B A , Ngadiwiyana N , Ismiyarto I , Sarjono P R
Published: June 2020

Synthesis of eugenol-divinylbenzene copolymers were carried out by reacting eugenol with various percent weight of divinylbenzene in a reactor at room temperature for 24 hours in the presence of sulfuric acid as a catalyst. Methanol was used to quench the copolymerization process. The effect of DVB mass on copolymer properties was studied based on molecular weight, thermal stability, surface morphology and swelling degree of the copolymers produced. The weight percent of the added DVB was responsible for the molecular weight of the copolymer by multiplying the site for propagation in the copolymerization process. In addition, the greater DVB used the better thermal resistance of polymer is obtained, which is possibly due to the higher number of DVB causing the larger cross-linked polymer network to increase the polymer bond thermal resistance. The swelling degree value was also affected by the number of crosslinkers used, in which make the polymer material become harder to expand. However, the influence of the weight percent of DVB was not seen on the copolymer morphology.
Synthesis of derivatives azomethine compounds bonded to alkoxylated benzene and their antibacterial activity tests
Authors: Ismiyarto I , Rizki N , Ngadiwiyana N , Sarjono P R , Prasetya N B A
Published: June 2020

Azometin compound has been synthesized from addition-elimination reaction between aromatic aldehyde compounds such as benzaldehyde, veratraldehyde, piperonal with primary amine compound from ethylenediamine. The presence of imine group (>C=N-), and alkoxy groups such as methoxy (-OCH3) and methylenedioxy (-O-CH2-O-) affected to their activity as antibacterials. In the synthesis of methoxy substituted azomethine compound from verataldehyde with ethylenediamine to produce N,N’-Bis(3,4-dimethoxybenzylidene) ethylenediamine in the form of white powder has a melting point of 164.8–166.2°C and in about 36.08% yield. In the synthesis of methylenedioxy-substituted azomethine compound from piperonal with ethylenediamine produced N,N’-Bis(3,4-methylenedioxybenzylidene) ethylenediamine in the form of greenish-white solid has a melting point of 176,3–177,4°C and in about 67,88% yield. In the synthesis of non-substituted azomethine compound from benzaldehyde with ethylenediamine produced N,N’-Bis(benzylidene)ethylenediamine in the form of orange solid has a melting point of 110.2-111.4°C and in about 34.82% yield. Antibacterial activity of compound N,N’-Bis(3,4-dimethoxybenzylidene)ethylenediamine, N,N’-Bis(3,4-methylenedioxybenzylidene)ethylenediamine, and N,N’-Bis(benzylidene) ethylenediamine with inhibitory zone diameter 0, 25; 3,08; 0.06 mm in S.aureus bacteria (G+) and 3.26; 4.61; 3.48 mm in E.coli bacteria (G−).
Economic analysis of planning for utilization of tabang hydro power plant
Authors: Windarta J , Saptadi S , Handoyo E , Machfudz L , Renaldo D , Saintekha M A
Published: June 2020

From the technical side, analyzing the hydropower design planning that matches the conditions of the Belayan River. From the economic side, analyzing the feasibility of hydropower projects through investment costs along with cash flow to the economic life of the project, using several methods, namely Net Present Value (NPV), Payback Period (PBP), Benefit Even Point (BEP), Benefit-Cost Ratio (B-CR), and Internal Rate of Return (IRR). The results of technical analysis with reliable discharge Q (10%) produce an output power of 439,4 MW with 4 generators, the power is then transmitted to the Melak Main Station with a distance of ± 100 km. Investment costs incurred in the planning of the construction of the Tabang hydro power plant (PLTA) in East Kalimantan is 3.673.356.951.235. The net present value (NPV) obtained is Rp.3.911.323.016.835 with a return on investment of 7.77 years and a break-even point for expenses and income in the 11,36 year. The ratio of project cost and benefit ratio is 1,32 and IRR (Internal Rate of Return) calculation is 19.53%. These results indicate that the plan to build a Tabang hydropower unit in East Kalimantan is economically feasible.
Analysis of queue and performance of automatic toll booths with a normal distribution (case study: automatic booths toll gate muktiharjo)
Authors: Sihotang E , Sugito  , Mustafid  , Ispriyanti D , Prahutama A , Rachman A
Published: June 2020

Queue process is a process related to the arrival of customers in a service facility, waiting in line queue if it cannot be served, get service and finally leaves the facility after being served. Research on the queue process can be seen directly through the queue system. Queue models and their distribution were obtained using the Sigma Magic program. The model of the vehicle queue system at the Muktiharjo Automatic Toll Gate is (NORM/NORM/4):(GD/∞/∞). Based on the values of the queue system performance measures obtained through the MATLAB GUI program as a whole it can be concluded that the queue of vehicles at the Muktiharjo Automatic Toll Gate has a condition where the average number of vehicles estimated in the system every 30 minutes is 99,2564 vehicles. The average number of vehicles in the queue system every 30 minutes is 98,2557 vehicles. The waiting time in the system is estimated to be around 15,51732 seconds. The estimated waiting time in line is around 15,36084 seconds. The queue system has a busy opportunity for 63.2849%. The simulation of the vehicle queue system at the Automatic Toll Gate of Muktiharjo Toll Gate by using ARENA is optimal with 4 automatic toll booths.
Supplier selection in rank order using fuzzy ahp and fuzzy molp with sensitivity analysis
Authors: Kurniawan F H , Surarso B , Suseno J E
Published: June 2020

Supply chain management (SCM) plays a great role in any company, a good SCM requires a good selection of all its components. One of the components is the raw material supplier selection that needs to consider both tangible and intangible factors in each supplier. Therefore, we can use fuzzy AHP which uses an intangible approach and fuzzy MOLP which uses a tangible approach. In this paper, we aim to use both methods to get the rank order of the best suppliers from all 5 suppliers in a woodworking company. The result shows that both methods can work together as the rank order from both methods gives the same result. However, sensitivity analysis is done in case both methods give different rank order. Sensitivity analysis shows that change in criteria from 10% to 100% make a variance in fuzzy AHP from 0% to 30% while fuzzy MOLP from 75% to 100%. That means fuzzy AHP is more robust than fuzzy MOLP. We also found that fuzzy AHP is influenced heavily by the expertise of the expert as two experts give different results while fuzzy MOLP is more objective-oriented using real data. These results suggest that each Method has its own characteristics that must be put into mind when we use it.
Modeling of composite stock price index (CSPI) using semiparametric regression truncated spline based on GUI R
Authors: Marbun W , Suparti  , Maruddani D A I
Published: June 2020

The Composite Stock Price Index (CSPI) is widely used as the beginning of consideration for investors to invest, because from the CSPI it can be known the general situation of market conditions is whether stock prices are experiencing an increase or decrease. This condition is characterized by a decrease or increase in the price of the CSPI. The Amount of Money Supply and the NASDAQ Index is thought to affect the price movements of the CSPI. The Amount of Money Supply has a nonparametric relationship pattern to the CSPI and the NASDAQ Index has a parametric relationship pattern to the CSPI. The correct method for conducting modeling is use the semiparametric spline truncated regression. The semiparametric regression spline truncated coefficient is estimated using the Ordinary Least Square (OLS) method which is determined based on the polynomial degree, much and the location of the optimum knot point is seen from the criteria of Mean Square Error (MSE). This study uses (Graphical User Interface) GUI R with the intention of facilitating the analysis process. The data used are monthly data from June 2014 to March 2019. Based on the results of the analysis that has been done, the best semiparametric spline truncated regression model with order 3 with the optimal three knots is 4246.361, 4443.078, and 4730.38. Evaluation results the in-sample data model produces a coefficient of determination of 90.25%. The results of the performance evaluation of the out sample data model resulted in a MAPE value of 3770204% indicating the performance of the model was very good.
Usability testing mozita application based on use questionnaire model
Authors: Rizal M F , Widodo A P , Adi K , Riyanto D E R , Nurhayati O D
Published: June 2020

Mozita is an application used by midwives to record and report the toddler nutritional status in the local health center (Puskesmas). In addition to nutritional status information, Mozita can present information that is used by heads of puskesmas, district health offices and provincial health offices for monitoring and decision making in terms of health policy based on nutritional status. To be able to increase application usage, feedback from users is needed. With USE Questionnaire-based usability testing covering aspects of Usefulness, Satisfaction and Easy of Use. Usability testing is focused on the interaction part of the user interface (midwife), as the main source of data collection. This study used 15 midwife respondents who were randomly drawn from puskesmas in the city area of Semarang. The technique used to measure usability testing is to provide an explanation and guidelines for using the Mozita application before respondents fill in the questionnaire using a Likert scale from 1 to 7. The questionnaire used is equipped with in-depth interviews for question items whose Likert scale value is less than equal to 3 The indepth interview aims to provide a focus on improving the Mozita application interface to suit user needs. The results of usability testing that has been done on the Mozita application shows that the value of the Usefulness component is 84.52%, Easy of Use is 83.53%, Easy of Learning is 80.95%, and Satisfaction is 85.03%. Based on the value of each component measured shows that the Mozita application has a high usability value that is equal to 83.52%, and makes it easy for users to carry out work more efficiently. Some user feedback related to satisfaction aspects, especially in the Mozita application layout section is still simple needs to be done for a better layout design.