cover
Contact Name
-
Contact Email
-
Phone
-
Journal Mail Official
berkala.saintek@unej.ac.id
Editorial Address
-
Location
Kab. jember,
Jawa timur
INDONESIA
BERKALA SAINSTEK
Published by Universitas Jember
ISSN : -     EISSN : -     DOI : -
Berkala SAINSTEK (BST) merupakan jurnal ilmiah yang memuat artikel hasil penelitian di bidang sains dan teknologi. Secara khusus BST diperuntukan bagi penulis internal mahasiswa Universitas Jember bidang fisika, matematika, biologi, kimia, teknik sipil, teknik mesin, teknik elektro dan sistem informasi. Namun BST juga menerima artikel dari penulis eksternal sepanjang memenuhi kriteria dan dalam lingkup bidang sains dan teknologi.
Arjuna Subject : -
Articles 254 Documents
Cover BST Volume 10 No 2 (2022) BERKALA SAINSTEK, Jurnal
BERKALA SAINSTEK Vol 10 No 2 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

On The Modification of Chaos Game Rules on A Square Purnomo, Kosala Dwidja; Mawarni, Anindita Setya; Ubaidillah, Firdaus
BERKALA SAINSTEK Vol 10 No 3 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v10i3.24183

Abstract

Fractal is a collection of geometric patterns found in nature and can also be a mathematical model visualization in which the pattern is repeated on a different scale. The formation of a fractal object can be done with a rule called chaos games. Chaos games explain a dot that moves erratically. On this research there will be random and non-random modification of the chaos game rules on a square. The purpose of this research is to make modifications and get visual results from modifications of the rules random and non-random chaos game. Depictions of random and non-random chaos game are carried out using MATLAB programs. Visualization of the random chaos game rule modification is a new fractal object that has self-similarity. Whereas modifications of the non-random rules by giving a particular sequence in selection a square point result in convergent points at specific coordinates. This is demonstrated by showing the value of the limit from the distance between points that produced by non-random chaos game is zero.
Bending Strength of Apus Bamboo Fiber Reinforced Asphalt Composite Materials as Small Ship Susanto, Eko; Maheswara, Yulian; Widodo, Akhmad Basuki
BERKALA SAINSTEK Vol 10 No 4 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v10i4.32604

Abstract

Bamboo is generally widely used as a material or construction material in homes. However, the use of bamboo as a raw material for shipbuilding is not yet available. To make bamboo as a material in shipbuilding, the bamboo is assembled or made into a composite to meet class standards as a material for shipbuilding. In this study, the composites used were apus bamboo fiber and asphalt. The method of making the composite uses the hand lay-up method with variations of 1 layer of reinforcement, 3 layers of reinforcement, and 5 layers of reinforcement. The dimensions of the test specimen size refer to ASTM D 790-3 which is then carried out by bending tests to determine the strength of the material due to loading and the elasticity of the material. Furthermore, the results of the bending test will be analyzed using the Anova method and compared with the standard material class in ship construction. Results Asphalt composite material with apus bamboo fiber has the highest bending test value of 27,068 Mpa and the lowest bending test value of 25,998 Mpa. Based on these results, it is stated that the Bamboo reinforced asphalt (BRA) material has not been able to match and even exceed the Bamboo reinforced plastic (BRP) material in the woven, non-woven and random fiber variants. It is influenced by the diameter, and the strength of the shape between the fiber and the matrix.
Cover BST Volume 10 No 3 (2022) BERKALA SAINSTEK, Jurnal
BERKALA SAINSTEK Vol 10 No 3 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Tree Ferns of C. contaminans and C. orientalis from Biosite Erek-erek Geoforest of Ijen Geopark, Banyuwangi Ulum, Fuad Bahrul; Setyati, Dwi
BERKALA SAINSTEK Vol 10 No 3 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v10i3.31738

Abstract

The tree ferns abundant in the ecotourism area of the geoforest erek-erek biosite is represented as ancient plants. However, species list and their composition as diversity richness data is still lacking the in the conservation area. The aims of of this study was to determine the tree ferns and provide the description of the species. Observations on the morphological characters of plants were carried out directly in the field of tree ferns habitat at the Ijen geopark, Banyuwangi, while other morphological and anatomical determinations were conducted in laboratory. The tree ferns identified in the erek-erek forest were two species i.e., Cyathea contaminans and Cyathea orientalis. The main distinguishing characteristics of these species are: stem height, stem surface, attachment of the remaining petiole, scale color, crozier size, indusium and spore shape. This article also provides descriptions of the species and the information regarding conspicuous characters that can be used for species determination in the field. We also propose further conservation efforts to preserve the tree ferns in their habitat.
Effect of Nozzle Tip’s Variation to The Duration and OXY-LPG Gas Consumptions Using Manual CuttingMethods in Shipyards Mardhotillah, Zahro Wanda; Kristiyono, Tri Agung; Aditya, Bagus Kusuma
BERKALA SAINSTEK Vol 10 No 4 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v10i4.32389

Abstract

In maritime industry, especially shipbuilding in Indonesia, various of cutting processes are implemented, which one is Gas Manual Cutting. Generally, gas requirements and duration of plate cutting processes are calculated based on previous work experience. The use of different nozzle tips by the operator will affect to gas consumption and cutting duration in each process. The purpose of this study was to determine the effect of variations in the tip-nozzle size on the duration and OXY-LPG gas requirements in manual plate cutting. The research was conducted using an experimental-based research with linear regression analysis using the ANOVA method. Based on the results of data analysis, it can be known that the larger the diameter of the nozzle tip, the requirements for OXY-LPG gas will increase by following the equation ????=0,1117????+0,3533 for Oxygen and ????=0,025????+0,0489 for LPG. Meanwhile, the larger of nozzle tip diameter can cause a decrease in the cutting duration required by following the regression equation ????=−28,603????+293,01.
Performance of Ceramic Membrane Modified with Corncob Activated Carbon for Efficient Remazol Red Removal in Batik Wastewater Ardiyanto, Muhammad Malik Firdaus; Rahmayanti, Maya
BERKALA SAINSTEK Vol 10 No 4 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v10i4.34941

Abstract

A ceramic membrane modified with corncob activated carbon (CMCC) has been successfully prepared and used to reduce the concentration of remazol red in batik wastewater. This research aims to study the effect of corncob activated carbon (CC) in the ceramic membrane on the porosity of the ceramic membrane and its ability to reduce the concentration of remazol red dye in batik wastewater. The variation of % CC to the mass of clay used was 0%, 5%, 10%, 15%, 20%, and 25%. Characterization of CC includes ash content and characterization of CMCC includes porosity test, morphological analysis, and elemental distribution based on SEM-EDX. The results showed that the ash content of CC before and after activation was 5.625% and 2.974%, respectively. The CMCC porosity test results showed that the more CC added, the greater the porosity of the ceramic membrane. The elemental composition in CMCC is dominated by O, Si, Al and C. The addition of 10% CC obtained the optimum composition on a ceramic membrane. % removal of remazol red is 83.9%. The COD values of batik wastewater before and after processing with CMCC were 484.286 and 26,339 mg/L, respectively.
The The Effect of Simplicia Drying Method on the Acquisition of Active Compound Levels of Grinting Grass Simplicia Extract (Cynodon dactylon (L.) Pers.) Yasi, Ratna Mustika; Harsanti, Restiani Sih; Larasati, Tiara Trisna
BERKALA SAINSTEK Vol 10 No 3 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v10i3.32309

Abstract

The drying method is the most important step in maintaining levels active compound in the sample. This study aims to determine the effect drying method against levels of active compounds of grinting grass (Cynodon dactylon (L.) Pers.). Drying methods include sun drying and cabinet drayer. The results showed that the drying method in plants reduced the extractive gain from the levels of active compounds including flavonoids, polyphenols, steroids, terpenoids, alkaloids and saonins. Simplicia drying method gave a significant effect (p<0.05) on the extraction of the active compound content of grinting grass (Cynodon dactylon (L.) Pers.). Based on the two drying methods, the highest levels of active compound extractive were obtained in the cabinet drayer method compared to the drying method using sunlight.
Implementation of K-Means Clustering Method for Trend Analysis of Thesis Topics (Case Study: Faculty of Computer Science, University of Jember) Irianto, Maulana Rafael; Maududie, Achmad; Arifin, Fajrin Nurman
BERKALA SAINSTEK Vol 10 No 4 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/bst.v10i4.29524

Abstract

The development of information technology causes a large number of digital documents, especially thesis documents, so that it can create opportunities for students to take the same and not varied topics. Thesis documents can be grouped by topic by identifying the abstract section. The results of the grouping can be seen with the trend with data visualization so that it can be analyzed to find out the trend of each topic. Retrieval of data in the repository of the University of Jember through a web scraping process as many as 490 thesis documents for students of the Faculty of Computer Science, University of Jember. The preprocessing stage is carried out by text mining methods which include cleaning, filtering, stemming, and tokenizing. Then calculate the weight of each word with the Term Frequency - Inverse Document Frequency algorithm, followed by the dimension reduction process using the Principal Component Analysis algorithm, which is normalized by Z-Score first. The outliers removal process is carried out before classifying documents. Furthermore, document grouping uses the K-Means Clustering method with Cosine Similarity as the distance calculation and the Silhouette Coefficient algorithm as a test. The test results were carried out with various k values and the optimal value was obtained at k = 2 with a Silhouette value of 0.80. Then the topic detection uses the Latent Dirichlet Allocation algorithm for each cluster that has been formed. Each cluster is visualized with a line chart and Trend Linear algorithm and analyzed to find out the trend. From the results of the analysis, it can be concluded that the topic of Decision Support System Development is trending down, and the topic of IT Performance Measurement and Forecasting is trending up. It can be concluded that the topic of Decision Support System Development needs to be reduced so that other topics can emerge.
Cover BST Volume 10 No 1 (2022) BERKALA SAINSTEK, Jurnal
BERKALA SAINSTEK Vol 10 No 1 (2022)
Publisher : Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract