bluuebunny/crossref_metadata_2025 huggingface dataset:
An analysis of technical efficiency and factors affecting rice farming business production in Bombana regency, Southeast Sulawesi
Authors: Rachmasari Ariani Wa Ode
Published: May 2021

This study aims to (1) analyze the factors affecting production of rice farming business in Bombana Regency, (2) analyze the extent of technical efficiency of rice farming business in the Regency. The study was conducted from April to October 2019. Bombana was considered as the area in which the study took place because most of the people were rice farmers and they were potential to develop. There were 120 rice farmers participated in the study. The samples were taken using simple random sampling. Primary data were collected by interview based on questionnaire, while secondary data were collected by going over the official documents issued by authorized agency. The data were analyzed using stochastic frontier production-function analysis and Cobb-Douglass analysis. The result showed that (1) of all affecting factors, fertilizers such as NPK as well as the land area had positive and significant correlation to the rice production; (2) the average value of technical efficiency of rice farmers was 84% and there were 16% chance to increase the rice production with additional optimal production input.
Lab-scale experimental investigation concerning ex-situ bioremediation of mercury (Hg) contaminated soil by local bacterial isolated from Bombana mining area
Authors: Ambardini Sri , Yanti NurArfa , Dehe Kasmawati , Fajar Hasidu La Ode Abdul
Published: May 2021

Hg Contamination is a most common occurrence in the industrial area, caused by several industrial activity wich release Hg into environment, like industrial activity of gold mining in Bombana Regency Southeast Sulawesi, Indonesia. So that it need effort to controll Hg contamination, one of wich is bioremediation techniques using bacterial. The aims of this study were to know the effect of local bacterial and incubation time to reduce the Hg content at post-gold mining soil of Bombana Regency. This study was experimental research atlab-scale (ex-situ bioremediation) using Completely Random Design (RAL) with two factorial. The 1st factor was the kind of bacterial inoculum namely Pseudomonassp. strain LIIC (Ps), Bacillussp.strain LIIIC (Bc), and mixed inoculum both of these bacterial species (PB). The 2nd factor was incubation time consist of 1st week until 8th weeks incubation. Soil substrate contaminated by Hg was inoculated of bacteria inoculum as much as 100 mL/kg and incubated at room temperature for 8 weeks. Hg content was measured by AAS (Atomic Absorption Spectrophotometer).Data was analysed by software SAS. The result of inoculated of local bacteria and incubation times affect to the Hg content on post-gold mining soil. The highest reduction of Hg content at the treatment of Pseudomonas sp. LIIC inoculated was 98,89% with the optimum incubation time in the second weeks.
Antibacterial activity of fungi endophytic isolated from leaves the mangrove acanthus ilicifolius l
Authors: Yanti Nur Arfa , Jamili  , Ardiansyah  , Anwarrudin Syaiful
Published: May 2021

Endophytic fungi are able to synthesize secondary metabolites that act as antimicrobial compounds to protect the host plant from pathogenic microbes. In the present study, endophytic fungi isolated from leaves of Acanthus ilicifolius was characterized and their antibacterial activity was assessed. Characterization of endophytic fungi isolates was carried out based on morphological characteristics of macroscopic (colony) and microscopic. Antibacterial activity test was conducted by well diffusion method using 2 bacterial indicators, namely Escherichia coli (Gram negative bacteria) and Staphylococcus aureus (Gram positive bacteria). Six endophytic fungi were isolated from A. ilicifoliusleaves and 5 isolates among them had antibacterial activity, namely isolates DT1, DT3, DT4, DT6 and DST1 with broad-spectrum activity. Five endophytic fungi identified belonged to 3 genera; DT1 and DT4 are identical to the Genus Geotricum, DST1and DT6 are identical to the Genus Humicola and DT3 is identical to the Genus Aspergillus. This study demonstrates an interesting bottom-up approach to the discovery of new antibacterial compounds.
Blue carbon dynamics in mangroves and conservation of their services in the Coral Triangle Ecoregion, Southeast Sulawesi, Indonesia
Authors: Analuddin Kangkuso , Kadidae La Ode , Muhammad Yasir La Ode , Septiana Andi , Syahrir La , Rahim Saban , Pratama David , Fajar LD Abdul , Nadaoka Kazuo
Published: May 2021

Coral triangle eco-region is hotspot of coastal blue carbon, and contributes to the global carbon cycling. This study aimed to elucidate the blue carbon dynamics in mangroves and their importance services as source of blue carbon in the coastal zone of coral triangle ecoregion. The blue carbon content in mangrove sediment was analyzed, while blue carbon production and its export frommangroves leaf litterfallwasestimated. The results showed that the blue carbon content in mangrove sediment was significantly higher in deep of 40-50 cm than other layers(P< 0.05). The annual blue carbon production (g C/m2/year) was 495.80 for R. mucronata, 572.52 for C. tagal and 335.56 for R. apiculata. Moreover, the annual blue carbon exported g C/m2/year was 148.74 for R. mucronata, 171.76 for C. tagal and 100.68 R. apiculata. Overallcarbon production and carbon export from these mangrove species were 1403.88 and 421.18g C/m2/year, respectively.Therefore, huge blue carbon production and export by mangroves in this region contribute to the global carbon cycling in the coastal and marine environments. Thus, conservation of mangroves and their services is very important for maintenance the coastal productivity in the coral triangle eco-region.
Characteristics and Anti-Diabetics Activity of Jelly Drink Okra Mucus (Abelmoschus Escullentus L.)
Authors: Jariyah  , Arofah E M N , Sarofa U
Published: May 2021

Okra mucus is mucilage that contains food fibre, tannin, alkaloids, steroids, and flavonoids, so it has the potential as an anti-diabetic agent, which can be processed into an anti-diabetic functional beverage product in the form of a jelly drink. However, it still needs the addition of a gelling agent to form a jelly, for example carrageenan, while sucralose and stevia were used to add sweetness. The purpose of this study was to determine the characteristics and activities of anti-diabetic jelly drink okra mucus with the formula of adding carrageenan and low calorie sugar. The study used a completely randomized design of two factors: carrageenan (0.10; 0.20 and 0.30%) and sugar (sucralose; stevia) with a concentration of 0.02; 0.03 and 0.04%. Each formulation was repeated 2 times, the difference in the formulation was used Duncan’s further test (DMRT 5%). The results showed that formula with the addition of carrageenan 0.3% and stevia sugar 0.04% which produced okra mucus jelly drink with viscosity characteristics 279.50 cps, total soluble solids 15.00% Brix, gel strength 4.53 N, total phenol 76.63 mgTAE / g), anti-diabetic test (IC50) 32.60 mg / ml, and food fibre 1.29 g / 100g. Organoleptic test results showed an average taste score of 2.8 (not favoured - favoured), texture 3.7 (favoured - favoured), aroma 2.75 (not favoured), and colour 2.95 (not favoured - favoured).
Suitability Analysis of Pond Ecosystems on the East Coast of Sidoarjo for Seaweed Cultivation on Productivity, Quality and Carrageenan Content of Gracilaria sp
Authors: Purnomo T , Rachmadiarti F , Rohmatin D , Rahayu J
Published: May 2021

Gracilariasp. is seaweed that produces agar and carrageenan, which is needed by the food, pharmaceutical, textile, and cosmetics industries. The high demand encourages cultivation. This study aims to determine the suitability of the pond ecosystem on the east coast of Sidoarjo for the cultivation ofGracilariasp. The research was conducted in a pond in Kupang Village, Jabon District, Sidoarjo usingin-situobservational methods. Water samples were taken from the Aloo river and ponds, samples fromGracilariasp. taken purposively at 3 stations, namely station 1 Dusun Tegalsari, station 2 Dusun Kali Aloo, and station 3 Dusun Tanjungsari. The parameters measured include land suitability (temperature, pH, salinity, water Cd concentration), andGracilariasp. Productivity (carrageenan content). Analysis of Cd concentrations using the Atomic Absorption Spectrophotometer method. Analysis of carrageenan content using the Kjeldahl method. Data of Cadmium concentration analyzed descriptively qualitatively and compared with SNI 7387: 2009 and Kepmen LH No. 51/2004. The results showed that the pond ecosystem on the east coast of Sidoarjo was suitable for the cultivation ofGracilariasp.,Gracilariasp. yields met the quality standards where the Cadmium concentration was below the quality standard threshold, the carrageenan content was moderate.
Antibacterial Activities Test of Ethanol Extracts of Kundur Fruit (Benincasa hispida Thunb. Cogn) on Salmonella typhi Bacteria
Authors: Darmayani Satya , Alaydrus Syafika , Yunus Reni , Yuniarty Tuty , Dewi Niluh Puspita , Rosanty Anita , Supiati
Published: May 2021

One of the natural ingredients that can be used as medicinal plants is kundur fruit (Benincasa hispida Thunb. Cogn). Kundur is one of the plants that contain compounds that are efficacious in medicine. The people of the Moronene tribe in Southeast Sulawesi used to consume kundur fruit in a shredded way to treat typhoid caused by bacterium Salmonella typhi (S. Typhi). The general objective of this study was to determine the bioactivity of the ethanol extract of kundur fruit (B. hispida) as an antibacterial S. typhi. Determination of antibacterial activity was carried out using the broth microdilution method. The results showed that the ethanol extract of kundur fruit had inhibitory activity on the growth of S. typhi bacteria with a minimum inhibitory concentration (MIC) of 800 μg / mL. This activity was compared with chloramphenicol with a MIC value of 8 μg / mL. In conclusion, the ethanol extract of kundur fruit has the potential as a source of antibacterial compounds against S. typhi.
Synthesis of chitosan-CuO composite and it’s application as heavy metal adsorbent
Authors: Firnanelty  , Chadijah S , Ratna  , Nurhuda S , Sittiama
Published: May 2021

Shrimp shells is one of the alternative sources for the potential production of chitosan. Chitosan from shrimp shells extracted with acid has high extraction results. The chitosan obtained forms composite with CuO material (mixing materials). The study investigated the synthesis, characterization, and application of chitosan from shrimp shells and the ability of chitosan-CuO composites as heavy metal adsorbent. The physical characterisation its similarity with the commercial chitosan. The composite was made by mixing chitosan and CuO. The bond formation between chitosan-CuO showed by analysis of FTIR. Absorption of chitosan-CuO to mercury (Hg) was 87%. Chitosan-CuO is very potential as absorbent of heavy metal.
Antioxidant Activity of Chlorella vulgaris Used As an Antioxidant Cream
Authors: Putri T W , Nursida N F , Raya I
Published: May 2021

This study aims to analyze the antioxidant activity of Chlorella vulgaris for used as an antioxidant cream. The method used in this study is the DPPH method to measure the antioxidant activity of chorella vulgaris cream based on the IC50 value and the BSLT method for determining toxicity for cosmetic use. The result was that Chlorella Vulgaris cream had an IC50 value of 127 μg / mL with an antioxidant activity of 61.90%. As a control cream without the addition of Chlorella Vulgaris showed an IC-50 value of 79,423 μg /mL with antioxidant activity of 3.46%. Chlorella Vulgaris cream has a very high antioxidant activity compared to the control cream without the addition of Chlorella Vulgaris. Chlorella Vulgaris cream can be used as an anti-aging cream based on the LC50 value is non-toxic and has a pH of 5.5 and after storage the pH is 6.5 according to the pH of the skin, so it is safe to apply.
Utilization of Compost as ameliorant in a Nickel post mining soil
Authors: Zaeni A , Alwahab  , Hasmawati  , Hade S , Irnawati  , Susilowati P E
Published: May 2021

Southeast Sulawesi is one of the nickel producing regions. Nickel mining activities in addition to positive impacts can also have negative impacts such as decrease of soil and increased of accumulation of heavy metals in the soil. Therefore, couple solutions are needed to improve the quality of nickel mining soil, one of those is by providing soil amendments. The material that used in this research is compost. Compost fertilizer contains humic acid which has cation exchange ability so that it can be useful for remediating the nickel post-mining area. The research used a complete randomized design method by variating the ratio of compost to nickel post-mining soil. The method steps consisting of (1) Analysis of post-mining soil sample (2) Analysis of compost-mixed mining soil sample. The results showed that the best treatment was the 17% addition of compost to nickel post-mining sample which characterized by changes in soil characteristics, such as pH value 6.68 to 7.17 (neutral) ; C-organic content 2.01% to 3.69% (high); N-total 0.19% to 0.21% (moderate); P2O5 21.77 mg /100g to 25.03 mg/100g (moderate); K2O 15.13 to 17.77 (low); and nickel content of 1194.66 ppm to 988.86 ppm. Despite a decrease of nickel content in the soil, its level is still hazardous in term of human health.
Total Content of Phenol and Antioxidant Activity from crude extract Methanol of brown algae (Padina sp) collected from Kayoa Island, North Maluku
Authors: Khadijah  , Soekamto N H , Firdaus  , Syah Y M
Published: May 2021

Determination of total phenol content and antioxidant activity of brown algae (Padina sp) from Kayoa Island and determining the relationship between total phenol content and its antioxidant activity have been carried out. Crude extract of methanol was obtained by maceration of dried algae Padina sp. Determination of the extract secondary metabolites was carried out by phytochemical screening which showed the presence of alkaloid, phenolic, steroid, and flavonoid content. The total phenol extract was determined by the Folin-Ciocalteu method and the total phenol content was 4,43 mgGAE/g. Antioxidant activity was analyzed using the DPPH method and the IC50 value was 564,99 µg/mL. The total phenol content of the extract and its IC50 value shows a linear relationship y = 1218x - 4830.7 with a determination value R2 = 0.9981
The technique for separation and purification of gondorukem (gum rosin) from pine gum (pinus merkusii) with a simple distillation method
Authors: Natsir M , Nurdin M , Ansharullah A , Muzakkar M Z , Trimutia E , Irwan I , Salim L O A , Salmah S , Maulidiyah M
Published: May 2021

This study reports the processing and separation of gum rosin from pine gum (Pinusmerkusii). The research method was carried out with several stages, namely the process of tapping pine gum, the process of separation and purification. After the refining process, the gum rosin and turpentine oil are separated using a simple distillation technique. The results of gum rosin separation obtained from the distillation process were 86.67 with a soft point of 78.8°C, a vaporizing component of 0.976%, an acid number of 175.3125 and a saponification number of 178.81875. In addition to knowing the components of the gum rosin samples obtained, the identification of compounds was carried out using Fourier Transform Infrared Spectrophotometer (FTIR) and Gas Chromatography-Mass Spectrometry (GC-MS). The results of FTIR identification showed the presence of sp2C-H,-OH, sp3C-H, C=O,-CH2and - CH3groups, while GC-MS identification showed the presence components of Caryophyllene, Pimaric acid, Dehydroabietic acid, Abieticacid, and á-Pinene. The identification results indicate that the residue from the simple distillation is gum rosin.
Effect of hexamethylenetetramine surfactant in morphology and optical properties of TiO2 nanoparticle for dye-sensitized solar cells
Authors: Irwan I , Muzakkar M Z , Umar A A , Maulidiyah M , Salim L O A , Nurdin M
Published: May 2021

The past few decades Dye-Sensitized Solar Cells (DSSC) based on TiO2 nanoparticle have attracted much attention from researchers because of their promising Physico-chemical properties and high photoconversion efficiency. In this research, TiO2 nanoparticles mediated with hexamethylenetetramine surfactant were successfully synthesized by the hydrolysis method. The influence of hexamethylenetetramine surfactant precursor concentration on DSSC photovoltaic performance was investigated. The prepared samples are characterized by field emission scanning electron microscopy, X-ray diffraction, and UV–vis absorption spectroscopy. SEM analysis results show that the HMT surfactant has a big influence on the morphology, particle size, and crystal phase of TiO2 particles. The surface morphology exhibited the nanorice grain particles in all samples. By spectrophotometry, it was shown that the films had a bandgap of about 2.9 eV. The film promoted by HMT 0.3 M from DSSC showed a power conversion efficiency of 1.7%.
Isolation Mg(OH)2 from Dolomite with Extraction Process used HNO3
Authors: Sari N K , Ernawati D , Wurjani W
Published: May 2021

Dolomite MgCa(CO3)2 has not been used to the fullest in Indonesia, where the natural resources of dolomites are quite abundant and are available in very large quantities. Mg(OH)2 isolated of dolomite originated from the East Java region with the extraction process using nitric acid. Using variable time and temperature, to acquire the element Mg(OH)2. To get the greatest Mg(OH)2, the precipitation process from using NaOH, and isolating Mg(OH)2 from the Elements of Ca(OH)2 and other impurities with Na EDTA solutions. From research obtained the best condition Mg(OH)2 from dolomite with NaOH additions with a variable stirring time for 5 hours and a temperature of 45 °C is at 175.60 mg/L.
Physio-chemical Characteristic of Red Dragon Fruit and Pineapple Jam
Authors: Nurani F P , Sulistyoningsih E K B
Published: May 2021

Red dragon fruit is one of fruit that easy to find in Indonesia. The availability of red dragon fruit is quite abundant, especially in harvest season. Sometimes, it became a problem when the fruit didn’t sell out and causing some change of quality. One way to extend the shelf life of red dragon fruit is by making jam. Jam is a gel-shape and semi solid food. The making of red dragon fruit jam was combined with the addition of pineapple that contain pectin which help the formation of gels. Sugar was added as sweetener and also as preservatives. On the other side, sugar have a role in gel formation with pectin. Commercial pectin was added to support gel formation in making jam. The factors observed in this study were concentrations of sugar (50,60,70%) and commercial pectin (0, 0.3, 0.5%) that might influence some quality parameters of jam such as spread ability, total soluble solid (TSS), pH, vitamin C and antioxidants value. The best characteristic of jam with spread ability 13.5, 70.5% of TSS value, pH was 4.39, vitamin C value was 0.81% and antioxidants value 19145.91 ppm was obtained with the addition of 50% sugar without the addition of pectin.
Extraction of Acemannan Polysaccharides Active Substance from Aloe Vera Flesh with Ethanol Solvent
Authors: Redjeki Sri , Yaqin Ainul , Iriani
Published: May 2021

This study was conducted to extract Acemannan Polysaccharides from aloe vera flesh using ethanol solvents and obtain the optimum extraction temperature and deposition time of the extraction process. The process was carried out in batches and in a laboratory scale, with the principle of liquid solid extraction in a stirred glass beaker. The extraction temperatures were 25°, 30°, 35°, 40°, and 45° C and the deposition times were 10, 12, 14, 16, and 18 hours. Some other variables were: 50 cc aloe vera juice volume, 200 cc solvent volume with 96% ethanol concentration, 45 minutes stirring time, and 500 rpm stirring speed. The results obtained were: the largest sediment mass, which was 2.1967 gram, was obtained at extraction temperature of 45° C and deposition time of 18 hours. Based on the results of qualitative analysis, the highest acemannnan content was obtained at 14 hours of deposition with a stirring temperature of 40° C and with 515.18 mg/gram glucose content.
The Diagnosis of Misconception on The Concept of Acid-Base Theory in Prospective Teacher Students Used a Three-Tier Test
Authors: Rusmini  , Suyono  , Jatmiko Budi , Yonata Bertha
Published: May 2021

Several phenomena of misconception have been discovered worldwide. In misconception, students strongly believe in the truth of the answers chosen of the questions given but the answers are wrong. This study aims to identify misconceptions that occur in first year students on the concept of acid-base theory. These students are pre service student in chemistry education. As prospective teachers, these students should be free from misconceptions so that they will not bring misconception to their own students one day. This study used a three tier diagnostic test to diagnose misconception from 125 students (1st and 2nd year) as data resources. The students have been given paper and pencil test consist of 15 questions. Each question consists of three levels, namely the choice of concept answers at the first level. The second level is the reason for the answer to the first level question. The third part is the level of confidence in the answers and reasons. Data analyzed to determine the percentage of misconceptions. The results showed that the first year students experienced misconceptions type 1, 2 and 3 in the low category. There were no students who guessed the answers.
The Effect of the Mahkota Dewa (Phaleria macrocarpa) on the Density of Collagen Incision Wounds
Authors: Sulistyoning Suharto Idola Perdana , Etika Arif Nurma , Nurseskasatmata Satria Eureka , Yunalia Endang Mei
Published: May 2021

Wounds are a disorder in the continuity of the skin or mucosal epithelial layer, which is a result of physical or thermal damage The research purpose was to analyze effect of mahkota dewa (Phaleria macrocarpa) on the density of collagen incision wound of white rats (Rattus norvegicus). This research has used post test only control group design. The sample were 30 male rats that grouped into control (K1, K2, K3) and treatment (P1, P2, P3) groups. The control group was given 1%CMC, while the treatment group was given oral extract of mahkota dewa at a dose of 22.5 mg/kg bw. The data was analyzed by Kruskall Wallis test. The results showed that there were a significant difference of collagen density between control and treatment group. The mahkota dewa fruits extract increased the macrophage activity. Thus, the macrophage activity could increase the Transforming Growth Factor – ß (TGF-ß) secretion. The TGF-ß could stimulate fibroblast prolipheration. In addition, collagen synthesis could increased. Based on the results, Mahkota dewa (Phaleria macrocarpa) extract could increase the collagen density of incision wound of white rats (Rattus norvegicus).
ANALYSIS OF SERVICE LEVELS OF THE TIDORE-SOFIFI SPEEDBOAT MODE DURING THE COVID-19 VIRUS PANDEMIC
Authors: Gaus Abdul , Sultan Mufti Amir , Ayub Wahab Iis Hamsir , Abdullah Abd. Majid , Nu’man
Published: May 2021

Speed boat is one of transportation mode to service the Tidore-Sofifi route picking the customers up from Islands Tidore to Halmahera island vice versa clear. Many customers doing a traveling use this mode demands attention to the comfort and safety aspects of the mode user, especially at the Covid-19 pandemic moment. Condition on the ground indicates speedboat mode operating throughout the day, in any the weather picks up people and objects. The purpose of this research analyzes speed boat service level according to rating mode user transportation at the Covid-19 pandemic moment by using analyze method Importance Performance Analysis (IPA). To reach the purpose of this research is done some steps specifically: counting a decrease in the average number of customers per day, map the relationship between the importance and performance of each service indicator according to customer assessment. From the result of the research obtained that during the pandemic Covid-19 number of customers in daily average is carried decreased dramatically to 10,10% numbers of the total customer usually carried up in normal time. The level service from the speedboat transportation Tidore-Sofifi by the IPA method obtained variable has high the interests/expectations however the reality/performance is not good enough, is the availability variable of the first aid kit and availability Hand sanitizer /ACT. While the variable is considered less important by customers, but its performance is good, that is lighting in the night, availability life jacket, and availability rope thrower.
Geografis Information System of Determining the High School (SMA) Zonation in Merauke City in Receiving New Students (PPDB) Using the Buffering Method
Authors: Xaverius F , Lintang M , Putra Nasra Pratama
Published: May 2021

Education is one of the bases in creating an atmosphere, learning processes in increasing the knowledge of skills and character development of each person. The Education and Culture Office of the Merauke Regency based on the Permendikbud Republic of Indonesia No. 51 of 2018 and Permendikbud No. 20 of 2019 concerning zoning determination, if students want to register to be accepted at the school, they must pay attention to the distance between their place of residence and the distance of the closest school, so that there is an even distribution of the number of students, as well as the composition of knowledge from students nothing is too dominating as a whole but evenly. This research is carried out by utilizing the Geographic Information System (GIS) in determining to zone for students who will register to Senior High School (SHS) in the Merauke city area, to obtain information about the nearest school, based on Government regulations. the parameter used is distance radius. the method applied in this research is the buffering analysis model. This analysis model can identify locations to obtain coverage that can be used in identifying objects based on the radius, thus producing polygons around objects. The results of this study are in the form of GIS to SHS and can map and determine SHS zonation in Merauke City, as well as displaying the distribution of SHS in Merauke city.
Bullwhip Effect Reduction Using Vendor Managed Inventory (VMI) Method in Supply Chain of Manufacturing Company
Authors: Ernawati D , Pudji E , Rahmawati N , Alfin M
Published: May 2021

Prediction of the amount of production can be done by forecasting demand and using appropriate methods. The supply chain studied at ABC company consists of manufacturing (vendors) and sales offices. Initially forecasting is done at each level of the supply chain with different forecasting methods. Therefore, uniform forecasting methods are needed for each supply chain actor. Based on testing the forecasting method conducted, the Winter’s Method. The model is used to link forecasting and implementation using the Vendor Managed Inventory (VMI) approach. Inventory planning in the supply chain cannot be done individually and must be thought of as a coordinated system. Inventory control is done by using the optimal lot calculation, namely Economic Order Quantity (EOQ). Based on demand forecasting and optimal lot determination, it can be calculated the value of the Bullwhip effect that occurs after the use of VMI in the supply chain has changed from 1.359 to 0.514 at the Manufacturing level.
Workload Identification Using the National Aeronautics and Space Administration Task Load Index (NASA-TLX) Method of Rolling Mill Operators in the Production Department at PT Jaya Pari Steel Surabaya
Authors: Handoyo H , Maharani D I
Published: May 2021

This study aims to determine the level of the workload of rolling-mill operators in the production department at PT Jaya Pari Steel. The study includes four steps: surveying, making questionnaires, distributing questionnaires, and data processing. The main problem faced by the company is the high workload that must be carried out by the operators so that the measurement of workload, in this case, using the NASA-TLX method, is required. The criteria emphasized in measuring workload covers six indicators: Mental Demand (MD), Physical Demand (PD), Temporal Demand (TD), Effort (EF), Own Performance (OP), and Frustration (FL). This study involved 168 respondents and found that the value of an indicator of physical need (PD) has an average value that is greater than other indicators. The results showed that: 1) seven operators felt the workload with a very high level in the range 80-100 while 11 other operators felt the workload with a high level in the range of 50-79, 2) the working environment conditions at PT Jaya Pari Steel needed to be improved to elevate the operator performance. The unsupportive working environment, such as weather, room temperature, noise, and lack of lighting and ineffective shifting of work systems are factors in the high workload of rolling mill operators.
Machine Maintenance Planning in Manufacturing Company using RCM II Methods
Authors: Pradipta Haris Salsabila Tyas , As’adi Muhammad , Montreano Donny
Published: May 2021

Production machine is a crucial thing to be taken care of in order to keep the production flow stays in the right time, therefore maintenance management is needed. PT. XYZ is a manufacturing company that produces cables. One of the machines that are used and often experiences downtime is the drawing machine. Preventive Maintenance handling interval schedule could be designed by using Reliability Centered Maintenance II method. There are several ways for the data processing, which are FMEA calculation, RCM II Diagram Decision Worksheet, TTF and TTR parameter calculation, determining the correct distribution using Least Square Curve Fitting and Goodness of Fit, MTTF and MTTR calculation, reliability comparation between the conditions before and after the Preventive Maintenance is implemented, cost savings comparation between the condition before and after the maintenance is done. This research proves that interval 3 formulation with the Pay Off for 361 hours, Dancer for 327 hours, and Double Spooler for 174 hours would enhance the reliability of Pay Off to 52%, so could it to Dancer (to 57%) and Double Spooler (75%). It also proves that by implementing Preventive Maintenance with the formulated interval and the result of RCM II Decision Worksheet indicators would produce in cost savings for the Pay Off part to 25,96%, the Dancer to 35,1%, and Double Spooler to 53,52%.
The Implementation of Maintenance Quality Function Deployment (MQFD) to Improve the Quality Maintenance Management for the Upstream Oil and Gas Industry
Authors: Djumantara Ulfah Aulia , As’Adi Muhamad , Dewi Alina Cynthia
Published: May 2021

The global energy market is still dominated by oil and gas energy. Pipeline is one of the most efficient means of distributing crude oil. In an oil and gas production unit, pipes are a means that often fails. A pipeline will operate optimally if it gets good maintenance. The concept of Total Productive Maintenance (TPM is an implementation subject that includes the concept of quality improvement engineering, or commonly known as TQM), but in its application, TPM eliminates one of the strategies in TQM, which reflects the voice of the operator (user’s voice) to influence quality improvement ongoing maintenance, so as to perfect the TPM approach, a supporting technique is needed that can reflect the operator’s voice, namely QFD, so that the combination of the two methods or so-called Maintenance Quality Function Deployment (MQFD) models is considered to be able to improve the quality of maintenance because it is a more comprehensive approach, and involves all elements involved, so that the expected quality improvement can be in accordance with the rules of total quality management Based on the results of the TPM parameter calculation, it is known that all OEE values have met the world’s standard of 86%. in carrying out its operations there are still reports of damage, leakage, and vandalism in the production pipeline. Based on the results of the identification of user’s voice, there are 19 attributes of maintenance quality that must be prioritized.
Innovative trend analysis of annual maximum precipitation in Gowa regency
Authors: Sanusi W , Abdy M , Sulaiman
Published: May 2021

Floods and drought are two events that can have a negative impact on human survival. In addition, the impact of these two events can also affect agriculture, fisheries, tourism, housing, transportation and others. Trend analysis is an analysis that can be used to identify extreme rainfall events such as floods and drought. The results of the trend analysis can be useful for water resource planning and management. Therefore, the aim of this study is to obtain an overview of the annual maximum precipitation trend in Gowa Regency. The study uses the daily precipitation data from the Sungguminasa and Bonto Sallang Stations of Gowa Regency for 31 years (1988 – 2018). The data was obtained from the Water Resources, Human Settlements, Spatial Planning and Development Office of South Sulawesi Province. The method used is the Mann-Kendall test, Theil-Sen approach, and innovative trend analysis. The results of a lag-one serial correlation test found that all stations are serially independent. Based on the MK method that both stations show negative trend, but significant only at Sungguminasa station at the 95% confidence level. The results of the ITA method show that all stations are significant negative trends at the 95% level. One of advantages of the ITA method is the ability to detect the significant hidden trends in time series.
Evaluation of the Accuracy of Spatial Data in Detecting the Rate of Land Change in Sinjai District
Authors: Muhlis  , Fatmawati  , Rahim Iradhatullah , Syamsia
Published: May 2021

Aerial photo interpretation can make it easier to detect, identify and delineate the presence of an area so that it can save time and effort and costs to observe directly the area in question. With the presence of satellite images, we can retrieve data from an area without having to visit that area. In this research, the authors use 3 (three) types of satellite image data, namely Landsat 8 satellite image data with an accuracy of 30 meters,. The objectives of this study is to evaluate the rate of accuracy of spatial data in detecting the rate of land change between 2014 and 2019 in Sinjai Regency. This research is closely related to the enumerative induction process (calculation based induction). To find out the level of accuracy of the data from the results of image interpretation, a field check was carried out by taking a sample point of about 20% of the total pixels of 911111 pixels, so that 191 points were obtained which were distribution points for the accuracy test of using image data to evaluate the accuracy level of land cover based on 2019 image data. The overall accuracy test uses the Kappa formula.
Global Analysis of Stage Structure Two Predators Two Prey Systems Under Harvesting Effect for Mature Predators
Authors: Pratama R A , Ruslau M F V , Nurhayati
Published: May 2021

This article examines set a prey-predator population model system with structural stages. Development of a mathematical model of a sustainable population of a population of living things. Structure stages are formed in predator populations, namely immature and mature. The predation function that corresponds to the characteristics in the ecosystem is the predation process of Holling I. The interaction in the population model that is carried out analysis is the equilibrium value formed from the population model. There are eight equilibrium values that arise from simple simulations. The equilibrium isE1(0,0,0,0),E2(0,k,0,0),E3(k,0,0,0),E4(k,k,0,0),E5(0,0,0,A1),E6(A2,0,A3,A4),E7(0,A5,A6,A7) andE8(A8,A9,A10,A11). However, only one equilibrium value is analyzed to obtain stability. Stability is seen by requiring four eigenvalues with the Jacobian matrix. As well as the chosen value is used to find the amount of harvest carried out. The linearization of differential equations is an alternative way in this study to obtain equilibrium values. Each equilibrium value has the characteristics and terms of its stability. The Routh-Hurwitz criterion becomes a condition of its stability characteristics. Meanwhile, exploitation efforts in the population are carried out to see the changes that occur. Harvesting carried out obtained harvesting businessW= 0.01313666667. For the maximum benefit obtainedπ= 4.997259008. This advantage is the stability and sustainability of the ecosystem.
Analysis of Drug Forecasting with Single Moving Average and Single Exponential Smoothing Approach (Case Study in Jombang Regency 2017-2019)
Authors: Restyana Anggi , Savitri Lisa , Laili Nur Fahma , Probosiwi Neni
Published: May 2021

Drug forecasting is done by all health facilities including government’s health facilities. It aims to consider the type of medication, the amount needed to realize a good drug management system. However, a of methods requires large selection using evaluation multiple measures of error in drug forecasting. The study aims to find out the method with the size of the least forecasting error between Single Moving Average and Single Exponential Smoothing. The data used is the annual primary data of the period 2017-2019. Samples amounted to 35 Public health centers. Forecasting calculation has been done using Single Moving Averages and Single Exponential Smoothing methods and testing errors using Mean Absolute Deviation and Mean Square Error methods. The study used 5 major medications with the most forecasting for 3 years. The drug with the most consecutive planning period 2017-2019 is paracetamol tablets 500 mg of 694,911 tablets, 126,713,379 tablets and 11,705,308 tablets. The conclusion of results showed a Single Moving Averages = 12,681 milions tablet with MAD = 0,594 milions and MSE = 666,841 millions. While, Single Exponential Smoothing = 7,949 milions with MAD = 4,557 milions and MSE = 372,884 millions. So, both of methos have small error measurement.
An input-output model of integrated farming system
Authors: Muhtar Norma , Cahyono Edi , Marsuki Iswandi R. , Arman
Published: May 2021

Tlie increase in the human population caused a decrease in the world agricultural area. Meanwhile, the agriculture sector is the biggest contributor to world food production. The integrated fanning system is integrating plants, livestock and fisheries management in a single harvesting cycle. The integrated farming system is one of the solutions to increase the efficiency of food production Plants are able to become food sources for livestock and fish. In this case, the output from plants turned into input for livestock. Meanwhile, fish and livestock excrement that used as plant fertilizer mean that livestock’s output becomes the input for the plants. The major purpose of the integrated farming system is to yield optimization. Optimization stands for minimizing of feeding and fertilizer cost and to optimize the yield of crops and livestock production. The simulation-based on the secondary data of integrated organic’ vegetables and livestock farming that has been done in Gapoktan Pandan Wangi in Village of Karehkel, District of Bogor. Leontief input-output economic model used to calculate the output of a component to meet the input of corresponding components. For the increase of vegetable sector demand of Rp500.000,00 required the increase of vegetable sector production of Rp46.915,097. For the increase of livestock demand od Rp200.000.00 required the increase of production in amount of Rp867.4S8,41. Thereby for Bokashi sector, in the increase of demand of Rp400.000,00 required the increase of production of Rp975.322,00. For the increase of silase sector demand of Rp30.000,00 required the increase of production of Rp76.456,00.
An automated content analysis model for forum moodle using semantic similarity
Authors: Tenriawaru A
Published: May 2021

The use of e-learning in Indonesia’s educational environment is increasingly widespread. It requires an improvement in the method of evaluating learning outcomes in e-learning. Moodle is one of the most popular learning management systems in the world of education, but Moodle does not yet have the tools to evaluate learner activities in every Moodle activity. For example, Moodle doesn’t have the tools to analyze the content of activity forums. This study proposes a model for analyzing message content in forums automatically. This model specifically aims to determine the relevance of the message to the course. The proposed model consists of three main processes: creating a dataset, detecting message relevance, and testing. Determination of the relevance of the message is based on the value of semantic similarity. Semantic similarity calculations are performed using Indonesian Wordnet and Levenshtein Distance Similarity. This model can help lecturers to detect which messages are relevant or worth and which messages are irrelevant or worthless toward the course. The proposed model is expected to improve the performance of evaluation systems of e-learning learning.
A review of the magnetic susceptibility of guano deposits in caves
Authors: Sandi I A , Fauzan M F A , Fitriani  , Rampe M J , Tiwow V A
Published: May 2021

The study of environmental magnetic methods using magnetic susceptibility parameters in cave guano deposits has not been widely discussed, especially in Indonesia. This method is relatively inexpensive, fast, affordable, and non-destructive. Environmental magnetism is associated with environmental changes such as climate change and anthropogenic effects. After a brief introduction to the fundamental of environmental magnetism, we describe several case studies regarding the properties of magnetic minerals and magnetic grains. This study was complemented with XRF results to identify the elemental composition.
Kernel multivariable semiparametric regression model in estimating the level of open unemption in East Java Province
Authors: Ampa Andi Tenri , Nyoman Budiantara I , Zain Ismaini
Published: May 2021

Semiparametric regression is a combination of parametric regression and nonparametric regression. Parametric regression curve components are approximated by multivariable linear functions, nonparametric regression curve components are approximated by Gaussian Kernel function. The purpose of this study is to obtain an estimate of the shape in semiparametric regression using the Kernel estimator and to model the Open Unemployment Rate (TPT) in East Java Province using the semiparametric regression model. This semiparametric regression model estimates on bandwidth. Semiparametric regression model is obtained by minimizing the Generalized Cross Validation function. The semiparametric regression model used to model TPT case data in East Java Province.
Trigonometric Learning Design with the Sibaliparriq Concept as a Learning Model
Authors: Ahmad H , Febryanti  , Kasbawati  , Akib I
Published: May 2021

This study aims to determine how the process and results of trigonometric learning designs that utilize sibaliparriq values as a learning model. This type of research is RnD (Research and Development) research which refers to the Dick and Carey development model with the procedure using the Mc Kenney cycle, which includes three stages, namely preliminary design, prototyping phase and assessment phase. The trigonometric learning design has been designed and validated and revised according to expert advice. The subjects of this study were students of Al Asyariah Mandar University, who took trigonometry courses. The trial results show that the design is effective and practical, namely (i) the average value obtained by students on the trigonometric learning outcome test is in the high category is 61,76. Students who complete the mastery are 29 out of 34 students or 85.29%. (ii) lecturers in implementing learning in accordance with the semester learning plan and are in the very high category. (iii) students are more active in learning. (iv) students generally respond very positively to learning. Thus, the trigonometric learning design process and results utilize the value of sibaliparriq as a learning model for quality Al Asyariah Mandar University students, namely meeting the criteria of validity, practicality, and effectiveness.
Effectivity of the Mathematics Learning Model ICCACRE in Developing Mathematics Creativity of Junior High School Students
Authors: Alimuddin  , Ruslan  , Nashrullah
Published: May 2021

ICCACRE stands for Interaction, Connection, Collaboration, Application, Creativity, Reflection, and Extension. The seven words consecutively refer to the syntax of the mathematics learning model called ICCACRE. It is actually the result of the developmental research referring to the theory of development of Plomp. The theory contains five stages of development, Those are preliminary investigation, designing, realization, giving test evaluation and revision, and implementation. In the implementation or limited trial stage, it was conducted an experimental research to investigate the effectivity of the model in developing mathematics creativity of junior high school students. Students from class VIII-2 were selected as participants in this study based on the selection with cluster random sampling technique from all students class VIII of SMPN 27 Makassar for 2019-220. Mathematical creativity data were obtained using the mathematical creativity test developed by the researcher referring to the creative indicators: fluency, flexibility, and originality which was equipped with an assessment rubric. The collected data were analyzed with descriptive statistics to explore mathematical creativity in detail. Meanwhile, inferential analysis is used to see the effectiveness of the model in developing students’ mathematical creativity. The results showed that the students’ fluency was in the high category. Meanwhile, the flexibility and originality of students are included in the medium category. Normalized N-Gain mean. indicates that fluency and flexibility increase in high category. Is increasing originality in the medium category. Furthermore, the results of the infrential analysis show that the ICCACRE model is effective in developing the mathematics creativity of junior high school students.
The Identification of the Concept Understanding on Limit of Functions Based on Students’ Learning Styles in Mathematics Department at FMIPA UNM
Authors: Saputra A W , Minggi I , Djadir
Published: May 2021

This paper is a qualitative research with a descriptive approach. The aim of this paper is to identify the understanding on limit of functions concept based on students’ learning styles in Mathematics Department at FMIPA UNM. The subjects of the study were 6 students in Mathematics Department at FMIPA UNM consisted of 1 student at each category with a visual, auditory, kinesthetic, visual-auditory, auditory-kinesthetic, and visual-kinesthetic learning styles. The data collections were conducted through the data analysis of written test results on mathematical concept understanding and interviews. The indicators of understanding on limit of functions concept in this study among others are understanding the concept of epsilon-delta, understanding the absolute value concept as distance, understanding the implication statement concept, understanding to interpreting the limit of functions definition using graph, and understanding to proving the limit of functions in accordance with the formal definition. The results showed that subjects who were dominant in the two categories of learning styles were generally able to understand the limit of functions concept relationally, while subjects who were dominant in one learning style category were generally able to understand the limit of functions concept instrumentally.