Garuda - Garba Rujukan Digital

Article Per Year (5 Year)

All

Jurnal Penelitian Saintek

saintek
Website

Published by Universitas Negeri Yogyakarta

ISSN : 14123991 EISSN : 25287036 DOI : 10.21831

Core Subject : Science,

Decision Sciences, Operations Research & Management

Arjuna Subject : -

Articles 286 Documents

5 6 7 8 9

IMPROVED RATIO OF GERAM RESTRICTIONS AND REDUCTION OF PAHAT PAID WITH MODIFIED WEARS OF PAVING CUTS AT DVA MACHINE Didik Nurhadiyanto; Mujiyono Mujiyono
Jurnal Penelitian Saintek Vol 10, No 1: April 2005
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

This research is aimed to determine the differences of chipcompression ratio and tool wear between a modified double cuttingtool and a standard cutting tool.The workpiece is made of VCN 150 with a dimension of e 1,75 inchand 200 mm long. Because the diameter of the blank is constant, the spindle rotation is set to 265 RPM Both cutters use the same coolant and have the same cutting angle. The properties to be varied are depth of cuts and feed Depth of cuts of standard cutting tool is formulated by the blank diameter substituted by the final diameter and than divided by two. The same formulation goes for depth of cuts of modified cutting tool. Tool wears and chip compression ratio values chosen is the biggest value on each cutting edge. Steps of this research one: Record the tool wear and chip compression ratio for each feed, which one 0,043; 0,066; 0,0875; and 0,/75 mmlrev while using depth of cuts of 0,5; I; 1,5 and 2 mm. Each treatment is done 5 times or each cutting stroke and the average is taken as a result. Comparing tool wear and chip compression ratio resulted from the utilization of modified cutting tool and standard tool.It can be concluded from the result of this research that (I) using modified cutting tool, there is an improvement of chip compression ratio equal to 6,74% compared to the standard cutter (2) using modified cutting tool there is a reduction tool wear equals to 14,53% compared the standard cutting /001.

TEMPERATURE MEASUREMENT COMPUTATIONS IN SURFACE SURFACE WITH DIFFERENT METHODS Masduki Zakarijah
Jurnal Penelitian Saintek Vol 8, No 2: Oktober 2003
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

This research goal to heat transfer rate prediction on every node insurface line and the difference of temperature measurement between direct measurement and numerical analysis based on Matlab with finite difference technique. Object of this research is aluminium plate to take shape a plaid square with size 5 x 22 em to divided in 75 node. The result of this research is heat transfer rate on every node in surface line between direct measurement and numerical analysis based on Matlab not difference of significance.

EFFECT OF ADDITION OF YEAST AND OLD TIME FERMENTATION TO VOLUME DONAT Endang Mulyatiningsih
Jurnal Penelitian Saintek Vol 8, No 1: April 2003
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

This research is aimed at: 1) finding out the influence of increasing the amountof yeast and fermentation time to the volume oj doughnuts, 2) finding out the minimum amount of yeast effective in doughnut formula, and 3) finding out thelength of fermentation time ideal for each doughnut formula with different percentage of yeast. The research uses experimental approach took place in the laboratory of Food Science, Department of Family Welfare Education, Faculty of Technology, Yogyakarta State University. Variables involved in this research consist of independent variables, i.e. different amount of yeast 1.1 %, 1.63%, and2.2%; length of fermentation time 45', 60', 75', 90', 105', and 120'; and dependent variable of the volume of doughnuts, controlling variable of thevolume of doughnuts beforefermentation. The mixing of ingredients to make the dough uses the straight dough method The research is controlled by means of carefully scaling the ingredient using sartorial scale with the level of accuracy up to one milligram, standardizing the temperature while fermentation and measuring the volume using the landscape method and. the data are analyzed further by means of two-way Anava. When any difference is obtained, the advanced- test Anava is performed using Duncan's Multiple Range Test(DMRT). The result of the research shows that: 1) there is significant difference of the doughnut volume based on various amount of yeast and length of fermentation time; 2) 1.1% of yeast is still effective to enlarge the volume of doughnuts without any significant difference based on the analysis of DMRT on the three different formulations with 90-minutefermentation time, and thus the ideal fermentation time for the three formulation tested is 90 minutes because over 90 minutes the dough will have got over proofing.

EFFECT OF VARIOUS MEASURES ON POWER ADSORPTION ION KROMIUM (III) AND COLOMUM (VI) IN LAND DIATOMAE Susila Kristianingrum; Siti Sulastri
Jurnal Penelitian Saintek Vol 13, No 1: April 2008
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

This research was done in Chemistry Laboratory FMIPA UNY. The aim of this research is to know the effect of diatomaeous earth soaking in a such acid on its adsorption power for heavy metal chromium(III) and chromium(VI) ions.The subject of this research is the diatomaeous earth from Sangiran Village, Sragen, Jawa Tengah. The object of this research is the diatomaeous earth properties soaking in such acid. Independent variables of this research are acid type, acid soaker concentration and the type of metal ion adsorbed. Dependent variable is its adsorption power for heavy metal chromium(III) and chromium(VI) ions. Experiment procedure consists of some steps: preparation, the diatomaeous earth treatment on chloride acid, nitric acid, and sulphuric acid, properties of the diatomaeous earth adsorbent for chromium(III) and chromium(VI) investigation. FTIR analyzing on original and treated diatomaeous earth and AAS analyzing to determine chromium(III) and chromium(VI) concentration before and after being diatomaeous earth soaker.The conclusion from this research was the diatomaeous earth soaking on such acids can caused adsorption power differences. Optimum adsorption power for chromium(III) occurred on a half concentrate chloride acid soaking (18.50%), concentrate nitric acid (65%), and concentrate sulphuric acid ((96%). Optimum adsorption power for chromium(VI) occurred on a half concentrate chloride acid soaking (18.50%), half concentrate nitric acid (32.50%), and an eight concentrate sulphuric acid (12%). Both original and treated diatomaeous earth has a similar FTIR spectrum pattern.

ANTIBACTERIAL POTENTIAL OF JAMU INGGU AGAINTS SOME BACTERIA CAUSING UPPER RESPIRATORY TRACT INFECTION Nunung Sulistyani; Ardina Nugrahani
Jurnal Penelitian Saintek Vol 20, No 2: Oktober 2015
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

This study aims to examine the potential of jamu inggu as an alternative antibacterial herb that can be used against Staphylococcus aureus, Streptococcus pnuemoniae, S. Pyogenes, and Pseudomonas aeruginosa that is causing Upper Respiratory Infections (URI). Antibacteria activity test of jamu inggu was using the Agar diffusion method by Kirby-Bauer. To test jamu inggu antibacterial activity against Staphylococcus aureus, Streptococcus pnuemoniae, S. Pyogenes, and Pseudomonas aeruginosa, the diameter of the test bacteria growth inhibition zone was measured. The formation of a clear zone around the disc indicates that jamu inggu has chemical compounds that are antibacterial against Staphylococcus aureus,while the Pseudomonas aerugenosa, Streptococcus pyogenes, and S. pneumoniae bacteria cannot be inhibited by jamu inggu. It was indicated by no formation of a clear zone around the disc. Result shows that jamu inggu can be used as an alternative source of antibiotics against the Staphylococcus aureus.

THE POPULATION OF AQUATIC SWEED AND AEDES SPP. AND THE DISTRIBUTION PATTERN OF DENGUE FEVER DISEASE Tien Aminatun; Tutiek Rahayu; Victoria Henuhili
Jurnal Penelitian Saintek Vol 21, No 1: April 2016
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

The study was aimed at ﬁ nding out the abundance of aquatic weeds in Rowo Jombor, the population of Aedes spp live in aquatic weed area, and the distribution pattern of dengue fever disease related to the population of aquatic weed and Aedes spp. Field survey was conducted for two months to collect the weed population data, mosquito larvae density, and environmental sanitation condition of the villages around Rowo Jombor. The study used quantitative descriptive analysis to see the correlation among weed density, Aedes spp population. The interview was conducted to make its distribution pattern.The results show that: (1) the density of aquatic weeds in Rowo Jombor was dominated by Eichornia crassipes mainly on Location V near he outlet, while the Location III which was located in the center of the swamp, the aquatic weed was not found; (2) the larvae of Aedes spp population which lived in aquatic weed area was not found; and (3) the result could not prove the relationship between the pattern of dengue fever disease distribution and the aquatic weeds in Rowo Jombor as the habitat for mosquito larvae of Aedes spp.

THE INFLUENCE OF GEOMETRY INCLUDED ROOMS ON GAS PRESSURE DISTRIBUTION: CASES ON SOURCE ION CYCLOTRON Silakhuddin Silakhuddin; Fajar Hidayat B. Santosa
Jurnal Penelitian Saintek Vol 17, No 1: April 2012
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

Ruang ionisasi dalam suatu sumber ion merupakan ruang yang di dalamnya bersirkulasi gas yang diionkan, terdiri atas housing katoda dan ruang anoda atau kolom plasma. Distribusi tekanan gas hidrogen di sepanjang sumbu ruang anoda telah dipelajari untuk geometri housing katoda yang bervariasi baik panjang maupun tingginya. Studi yang dilakukan secara simulasi menggunakan program komputer berbasis CFD dimaksudkan untuk menilai kemungkinan melakukan modifikasi geometri head yang sudah dibuat untuk mendapatkan unjuk kerja yang lebih baik. Hasil analisis dari simulasi tersebut menunjukkan bahwa geometri head yang sekarang sudah dibuat yaitu dengan panjang housing 42 mm dan tinggi 16 mm merupakan geometri yang optimum. Secara umum dapat dikatakan bahwa untuk suatu ruangan yang di dalamnya tersirkulasi gas, bila ukuran aliran masuk dan keluar gas yang kecil dibandingkan ukuran ruangannya, maka perubahan geometri yang simetri dari ruangan tidak mempengaruhi distribusi tekanan gas yang merata di dalam ruangan tersebut.Kata kunci: ruang tersirkulasi, tekanan gas, CFD, sumber ion

THE DEVELOPMENT OF STANDARDIZATION NATURAL COLOUR FROM BATIK OF STEAM BARK (Caesalpinia sappan L) BY SPECTROSCOPHY METHOD Arum Restu Widyasti; Astuti Lestari; Khoirul Amri; Fakhrizal Naufal; Kun Sri Budiasih
Jurnal Penelitian Saintek Vol 22, No 1: April 2017
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

The purpose of this research is to obtain a method of color standardization which is a consistent assessment of the color formed by secang natural dye, so it can be used as a reference color of natural dyes of batik.Standardization steps of natural dyes included taxonomic examination, preparation of secang dye by extraction, standardization process by spectroscopic measurement, with “rapid” dye as standard, application on batik process including batik pattern making and wax application on batik and batik coloring process with secang dye. Data was analized by absorbance vs wavelength obtained from red color formed by secang dye. The results showed that the maximum absorption wavelength of the standard red color was obtained at 450.20 nm. This value is used as the standard red color measurement

OPTIMIZATION OF NEURO FUZZY MODEL FOR DATA TIME SERIES WITH SINGULAR VALUE DECOMPOSITION METHOD Agus Maman Abadi; Dhoriva Urwatul Wutsqa
Jurnal Penelitian Saintek Vol 18, No 1: April 2013
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

This study aims to develop new procedures in optimal neuro fuzzy modeling for time series data. Specifically in this research, the development of new procedure in modeling fuzzy Takagi-Sugeno-Kang order one for time series data which parameter-parametemic determination is done by singular value and neural network decomposition method, in order to obtain method of forming neuro fuzzy model for time series data optimal. In this research, we have developed a procedure to get the optimal Takagi-Sugeno-Kang fuzzy model for time series data by optimizing the parameter value search in consequence of fuzzy rule using singular value decomposition method. A new model of neuro fuzzy modeling is optimized, the fuzzy model whose parametem optimization is based on the neural network by the singular value decomposition method. Parameters in consequent part of the rule of fuzzy are optimized by the singular value decomposition method and the parameters in the antecedent part of the fuzzy rule are optimized based on neural network backpropagation with gradient descent method.

BIOLOGICAL TEST AND CHARACTERIZATION OF PHOSPHATE RHIZOBACTERIAL ISOLATE USING CORN PLANT INDICATOR Tessa Novianty Putri Asova; Anggi Jingga; Mieke R. Setiawati; Tualar Simarmata
Jurnal Penelitian Saintek Vol 23, No 1 (2018): April 2018
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

Phosphate rhizobacteria (PR) plays an important role in increasing solubility and availability of phosphate for plants. The experiment to investigate the capabilities of PR isolates was conducted from March to August 2017 in laboratories and greenhouse. Bioassay test using the Murphy media and maize as indicator was arranged as a randomized block design consist of six treatments (one control and five isolates PR) and provided with five replications. The plant height, root length, and dry weigth of plant were measured at 14 days. The dissolved P and enzyme phosphatase production were measured using Bray I and Eivzy Tabatai methods. The result shows that the PR isolates had relatively different ability to dissolve of P, produce of phosphatase and to increase the plant growth. J1M and J5H isolates has produced of phosphatase enzyme 63.25 μg pNP/g/h and 62.84 μg pNP/g/h, soluble phosphate 66.24 ppm and 75.42 ppm. J1M and J5H isolates were able to produce dry weights of plants 728 mg and 660 mg (about 60.3% and 45.3% higher than control).UJI HAYATI DAN KARAKTERISASI ISOLAT RHIZOBAKTERI FOSFAT DENGAN INDIKATOR TANAMAN JAGUNGRhizobakteri fosfat (RF) berperan penting dalam meningkatkan kelarutan dan ketersediaan fosfat bagi tanaman. Eksperimen untuk mengetahui kemampuan isolat RF dengan menggunakan tanaman jagung sebagai indikator telah dilakukan sejak bulan Maret sampai Agustus 2017 di laboratorium dan rumah kaca. Uji hayati (bioassay) menggunakan media Murphy dan tanaman jagung sebagai indikator dilakukan dengan memanfaatkan rancangan acak kelompok yang terdiri dari enam perlakuan (satu kontrol dan 5 isolat RF) dan diberi ulangan sebanyak lima kali. Panjang akar, tinggi tanaman, dan bobot kering tanaman diukur setelah 14 hari. Produksi enzim fosfatase dan P-terlarut diamati dengan menggunakan metoda Eivzy Tabatai dan Bray I. Hasil penelitian menunjukkan bahwa isolat RF memilki kemampuan yang relatif berbeda dalam melarutkan P, produksi fosfatase dan meningkatkan pertumbuhan tanaman. Isolat J1M dan J5H menghasilkan enzim fosfatase sebesar 63,25μg pNP/g/h dan 62,84 μg pNP/g/h dan P-terlarut sebesar 66,24 ppm dan 75,42 ppm. Isolat J1M dan J5H mampu menghasilkan bobot kering tanaman sekitar 728 mg dan 660 mg (sekitar 60,3% dan 45,3% lebih tinggi dibandingkan dengan kontrol).

Page 7 of 29 | Total Record : 286

5 6 7 8 9

Filter by Year

2001 2025

Filter By Issues

All Issue Vol 30, No 2 (2025) Vol 30, No 1 (2025) Vol 29, No 2 (2024) Vol 29, No 1 (2024) Vol 28, No 2 (2023) Vol 28, No 1 (2023) Vol 27, No 2 (2022) Vol 27, No 1 (2022) Vol 26, No 2 (2021) Vol 26, No 1 (2021) Vol 25, No 2 (2020) Vol 25, No 1 (2020) Vol 24, No 2: Oktober 2019 Vol 24, No 1: April 2019 Vol 23, No 1 (2018): April 2018 Vol 23, No 2: Oktober 2018 Vol 22, No 2: Oktober 2017 Vol 22, No 1: April 2017 Vol 21, No 2: Oktober 2016 Vol 21, No 1: April 2016 Vol 20, No 2: Oktober 2015 Vol 20, No 1: April 2015 Vol 19, No 2: Oktober 2014 Vol 19, No 1: April 2014 Vol 18, No 2: Oktober 2013 Vol 18, No 1: April 2013 Vol 17, No 1: April 2012 Vol 16, No 2: Oktober 2011 Vol 16, No 1: April 2011 Vol 15, No 2: Oktober 2010 Vol 15, No 1: April 2010 Vol 14, No 1: April 2009 Vol 13, No 1: April 2008 Vol 12, No 2: Oktober 2007 Vol 12, No 1: April 2007 Vol 11, No 1: April 2006 Vol 10, No 2: Oktober 2005 Vol 10, No 1: April 2005 Vol 9, No 1: April 2004 Vol 8, No 2: Oktober 2003 Vol 8, No 1: April 2003 Vol 7, No 2: Oktober 2002 Vol 7, No 1: April 2002 Vol 6, No 1: Saintek 2001 More Issue

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kab. sleman,

Daerah istimewa yogyakarta

INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name -

Contact Email -

Phone -

Journal Mail Official -

Editorial Address -

Location Kab. sleman, Daerah istimewa yogyakarta INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kab. sleman,

Daerah istimewa yogyakarta

INDONESIA