Science and Technology Indonesia最新文献_第9页

A New Three-Parameter Mixed Poisson Transmuted Weighted Exponential Distribution with Applications to Insurance Data 一种新的三参数混合泊松变静音加权指数分布及其在保险数据中的应用

Science and Technology Indonesia Pub Date : 2023-04-15 DOI: 10.26554/sti.2023.8.2.235-244

A. Adetunji, Shamsul Rijal Muhammad Sabri

引用次数: 0

The Relationship of Multiset, Stirling Number, Bell Number, and Catalan Number 多集、Stirling数、Bell数和Catalan数的关系

Science and Technology Indonesia Pub Date : 2023-04-15 DOI: 10.26554/sti.2023.8.2.330-337

W. Wamiliana, Attiya Yuliana, Fitriani Fitriani

引用次数: 0

Drought Assessment in Aceh and North Sumatra Using Effective Drought Index 使用有效干旱指数评估亚齐和北苏门答腊的干旱

Science and Technology Indonesia Pub Date : 2023-04-15 DOI: 10.26554/sti.2023.8.2.259-264

Suhadi Suhadi, Supari Supari, I. Iskandar, Muhammad Irfan, H. Akhsan

{"title":"Drought Assessment in Aceh and North Sumatra Using Effective Drought Index","authors":"Suhadi Suhadi, Supari Supari, I. Iskandar, Muhammad Irfan, H. Akhsan","doi":"10.26554/sti.2023.8.2.259-264","DOIUrl":"https://doi.org/10.26554/sti.2023.8.2.259-264","url":null,"abstract":"Indonesia has two seasons and witnesses three rainfall patterns throughout the year. Although Aceh and North Sumatra experience low rainfall, the underlying causes of this condition are unknown. Unfortunately, studies on drought in these regions are very limited. This study uses the Effective Drought Index (EDI) to assess drought in these regions using daily rainfall data from 1985–2019 (35 years) from the meteorology, climatology, and geophysics agency stations. These stations are Sultan Iskandar Muda, Malikussaleh, Deli Serdang, and FL Tobing. In this study, the Ocean Niño Index (ONI) and the Dipole Mode Index (DMI) were used to identify El Niño years and positive and negative phases of the Indian Ocean Dipole (IOD). These indices were used to analyze drought-related climatic phenomena. The results obtained indicated that some drought events were not associated with a positive Indian Ocean Dipole or El Niño, as is typically the case. These include the extreme drought in 1989/90 and moderate drought in 1999 at Sultan Iskandar Muda, moderate drought at Malikussaleh (March to June 2008), moderate drought at Deli Serdang in 2010, as well as the drought from January to June 2006 at FL Tobing. Analysis of spatial patterns revealed that moderate droughts were more prevalent than severe and extreme droughts. These drought assessment results are essential for the mitigation of natural catastrophes.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41920146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Characterization of the Hydrophobic Surface of Nanocomposites Aloe vera/PS for Antimicrobial Pathogens 抗菌致病菌用芦荟/PS纳米复合材料的疏水表面表征

Science and Technology Indonesia Pub Date : 2023-04-15 DOI: 10.26554/sti.2023.8.2.212-218

Lathifa Zonesya Putri, R. Ratnawulan, R. Ramli, H. Rifai, F. L. Supian, Irna Humairah

{"title":"The Characterization of the Hydrophobic Surface of Nanocomposites Aloe vera/PS for Antimicrobial Pathogens","authors":"Lathifa Zonesya Putri, R. Ratnawulan, R. Ramli, H. Rifai, F. L. Supian, Irna Humairah","doi":"10.26554/sti.2023.8.2.212-218","DOIUrl":"https://doi.org/10.26554/sti.2023.8.2.212-218","url":null,"abstract":"The spread of pathogenic microorganisms on a large scale creates a health disaster for the world. Modifying the surface of the fabric so that it is antimicrobial pathogens with hydrophobic properties is one solution to inhibit the spread of microorganisms. Surface modification was carried out using Aloe vera powder as filler and polystyrene matrix with Aloe vera:PS composition variations of 1:5, 2:5, and 3:5 using the dip coating method and drying temperatures of 10◦C, 50◦C, and 90◦C. The characterization results that have been carried out with the best composition variations are 3:5 and 50◦C with a layered morphology using Scanning Electron Microscopy (SEM), resulting in a surface particle size of 21.243 nm, large contact angle/WCA using a Canon D350 camera with a size of 150.23◦, Fourier Transmission Infrared Analysis (FTIR) with the dominant functional group in the vibration band 2629 cm−1 indicates the presence of a long hydroxyl chain, the vibration band 1500 cm−1 with C-H stretching of the aromatic ring is caused by the characteristics of the polystyrene polymer and the wave number is 1700 cm−1 with stretching C=O which shows the characteristics of the carbonyl group in the Aloe vera sample is a flavonoid compound. The resistance of Aloe vera/PS solution to Klebsiella pneumonia resulted in a 20.18 mm diameter barrier showing strong resistance against bacteria and X-Ray Diffraction analysis showed that the AV powder was amorphous. Thus, the AV/PS 3:5 composition with a calcination temperature of 50◦C represents the greatest variation in the synthesis and characterization of hydrophobic thin films for pathogenic antimicrobial organisms.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41985270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Catalytic Activity of LDH-TiO2 and LDH-ZnO in Photodegradation of Procion Red LDH-TiO2和LDH-ZnO光降解产朊红的催化活性研究

Science and Technology Indonesia Pub Date : 2023-04-15 DOI: 10.26554/sti.2023.8.2.252-258

N. Yuliasari, Amri Amri, R. Mohadi, Elfita Elfita, A. Lesbani

引用次数: 0

Formulation of Set Covering Problem Using Myopic Algorithm and Greedy Reduction Algorithm in Determining the Location of Temporary Landfills in Semambu Island Village, Ogan Ilir Regency, South Sumatra 用Myopic算法和Greedy约简算法确定南苏门答腊Ogan Ilir县Semambu岛村临时填土位置的集覆盖问题

Science and Technology Indonesia Pub Date : 2023-04-15 DOI: 10.26554/sti.2023.8.2.184-194

F. Puspita, S. Octarina, L. Hanum, Chatrin Yohana Simamora, Helena Valenta Br Kemit, E. Yuliza

{"title":"Formulation of Set Covering Problem Using Myopic Algorithm and Greedy Reduction Algorithm in Determining the Location of Temporary Landfills in Semambu Island Village, Ogan Ilir Regency, South Sumatra","authors":"F. Puspita, S. Octarina, L. Hanum, Chatrin Yohana Simamora, Helena Valenta Br Kemit, E. Yuliza","doi":"10.26554/sti.2023.8.2.184-194","DOIUrl":"https://doi.org/10.26554/sti.2023.8.2.184-194","url":null,"abstract":"This study discusses Set Covering Problem (SCP) in designing the optimal temporary waste disposal site (TWDS) in Semambu Island Village using the Myopic Algorithm (MA) and Greedy Reduction Algorithm (GRA). The analysis was carried out and compared using a maximum distance of 500m and 1000m to get the best solution from two methods. The results of the p Median Problem by LINGO 13.0 software and MA with a maximum distance of 500m show the same TWDS location, namely Working Area (WA) 1, 2, 3, 4, 5, and 6 with the location of the candidate TWDS being at TWDS 2 WA 1, TWDS 1 WA 2, TWDS 2 WA 3, and TWDS 2 WA 5. For 1000m, it will be the location of the candidate’s TWDS being at TWDS 2 WA 1, TWDS WA 2, and TWDS 2 WA 3. Using GRA, results were obtained will be 4 TWDS, namely TWDS 2 Hamlet 1, TWDS 1 Hamlet 2, TWDS 2 Hamlet 3, TWDS 2, Hamlet 5. Then using GRA, 2 solutions are obtained, namely columns 2 and 5 which dominate. Column 2 nomination are Hamlets 1, 2, 3, and 6. Column 5 which dominates will be Hamlets 1, 3, 5, and 6.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44318037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Antibacterial and Antioxidant Activity of Endophytic Fungi Extract Isolated from Leaves of Sungkai (Peronema canescens) 松开叶内生真菌提取物的抗菌抗氧化活性

Science and Technology Indonesia Pub Date : 2023-04-15 DOI: 10.26554/sti.2023.8.2.170-177

Rian Oktiansyah, H. Widjajanti, Arum Setiawan, Sakinah Salman Ahmad Nasution, M. Mardiyanto, Elfita Elfita

{"title":"Antibacterial and Antioxidant Activity of Endophytic Fungi Extract Isolated from Leaves of Sungkai (Peronema canescens)","authors":"Rian Oktiansyah, H. Widjajanti, Arum Setiawan, Sakinah Salman Ahmad Nasution, M. Mardiyanto, Elfita Elfita","doi":"10.26554/sti.2023.8.2.170-177","DOIUrl":"https://doi.org/10.26554/sti.2023.8.2.170-177","url":null,"abstract":"Sungkai is a plant that is widely found in Indonesia. This plant is often used in traditional medicine so the biotechnology of endophytic fungi is highly needed due to natural resources from plants that have been reduced. This study reported on endophytic fungi found in sungkai leaves and the compound produced. Morphological and molecular identification through phylogenetic tree analysis was carried out to determine the endophytic fungal species found. Potato Dextrose Broth media was used for the cultivation process. Ethyl acetate was used as a solvent for the extraction and the evaporation process used a rotary evaporator. Antioxidant and antibacterial tests were carried out using the DPPH method and paper disc diffusion. Chromatographic techniques were used to isolate the compound and spectroscopic analysis was performed to identify its chemical structure. The results of the morphological and molecular analysis showed Trichoderma asperellum as an endophytic fungus identified. The pure compound obtained from this endophytic fungus was 4-hydroxybenzoic acid. The antioxidant and antibacterial activity showed a strong category (IC50 = 43.88 ????g/mL; MIC 64 ????g/mL). This compound was very likely to be a raw material for new antibiotics and antioxidants through further research with various modifications.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48291884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Bi-Univalent Function Classes Defined by Using an Einstein Function and a New Generalised Operator 用爱因斯坦函数和一个新的广义算子定义的双单价函数类

Science and Technology Indonesia Pub Date : 2023-04-15 DOI: 10.26554/sti.2023.8.2.195-204

Munirah Rossdy, R. Omar, S. C. Soh

引用次数: 0

Facile Fabrication of Layered Double Hydroxide-Lignin for Efficient Adsorption of Malachite Green 层状双氧水木质素的制备及其对孔雀石绿的高效吸附

Science and Technology Indonesia Pub Date : 2023-04-15 DOI: 10.26554/sti.2023.8.2.305-311

N. Palapa, N. Ahmad, A. Wijaya, Zaqiya Artha Zahara

{"title":"Facile Fabrication of Layered Double Hydroxide-Lignin for Efficient Adsorption of Malachite Green","authors":"N. Palapa, N. Ahmad, A. Wijaya, Zaqiya Artha Zahara","doi":"10.26554/sti.2023.8.2.305-311","DOIUrl":"https://doi.org/10.26554/sti.2023.8.2.305-311","url":null,"abstract":"Preparation of layered double hydroxide-lignin (lignin-Zn/Al) carried out by coprecipitation method. The FTIR spectra of lignin-Zn/Al displayed at 3448, 2939, 1620, 1381, 1118, 1041, and 601 cm−1. The characteristic peaks are located at 10.1°, 19.1°, 20.1°, 29.4°, 33.9°, and 60.4°. The lignin-Zn/Al nitrogen adsorption-desorption isotherm showed a Type-IV curve, indicating that it had a mesoporous structure. The H3 kind of hysteresis loop also provides evidence for the presence of mesopores within the lignin-Zn/Al complex. Lignin-Zn/Al, lignin, and Zn/Al had pHpzc values of 6.09, 3.01, and 6.09, respectively. Lignin-Zn/Al, lignin, and Zn/Al are positively charged when the pH of the solution is less than pHpzc, and they are negatively charged when the pH of the solution is more than pHpzc. The Langmuir and pseudo-second-order model best represented the MG adsorption onto all adsorbents. The lignin-Zn/Al, lignin, and Zn/Al were shown to have maximum Langmuir adsorption capacities of 83.034, 78.740, and 36.364 mg/g, respectively. Zn/Al adsorption capacity increased 2.28 times after being composited with lignin.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42050608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Fe3O4-SiO2-Alginate Photocatalyst for Textile Dyes Waste Degradation fe3o4 - sio2 -海藻酸盐光催化剂降解纺织染料废水

Science and Technology Indonesia Pub Date : 2023-01-19 DOI: 10.26554/sti.2023.8.1.108-115

Sri Wardhani, Herdian Akbar Mardiansyah, D. Purwonugroho

{"title":"Fe3O4-SiO2-Alginate Photocatalyst for Textile Dyes Waste Degradation","authors":"Sri Wardhani, Herdian Akbar Mardiansyah, D. Purwonugroho","doi":"10.26554/sti.2023.8.1.108-115","DOIUrl":"https://doi.org/10.26554/sti.2023.8.1.108-115","url":null,"abstract":"Fe3O4 is a photocatalyst that is used to degrade textile dye waste which can be collected and reused. Fe3O4 was prepared by coprecipitation method, then impregnated with SiO2 and sodium alginate. The purposes of this study were to investigate the degradation of textile dye waste using a Fe3O4-SiO2-alginate photocatalyst, to examine the light and dark test of photocatalyst under the influence of concentration and irradiation time. The type of light used was a 14.5-watt Philips LED lamp with a wavelength of 400-640 nm. Photocatalyst characterizations were conducted using FTIR, UV-Vis DRS, and XRD. The light and dark test of photocatalyst was carried out by photodegradation of textile dye waste with 0.5 g of photocatalyst with concentrations of 5%, 10%, and 15% and irradiation times were varied for 60, 90, 120 min. The degradation results were measured by calculating the COD value. The results of characterization by FTIR showed that the photocatalyst Fe3O4-SiO2-Alginate had absorption at wavelengths of 637.56 cm−1 and 3365.86 cm−1 which indicated the Fe-O-Si functional group and O-H stretching vibration. Results of UV-Vis DRS were analyzed using Origin Pro 2022 and revealed that the band energy gap for Fe3O4 and Fe3O4-SiO2 were 2.20 eV and 1.77 eV, respectively. The XRD results analysis with Match!3 software showed that for Fe3O4 had magnetite phases, while SiO2 had amorphous cristobalite phases. The 15% (w/v) Fe3O4 concentration in the form of powder and granules degraded batik liquid waste by 79.6% and 84.48%, respectively.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44544344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0