Pub Date : 2023-04-15DOI: 10.26554/sti.2023.8.2.227-234
Mi'rajunnisa Mi'rajunnisa, H. Suryadi, Sutriyo Sutriyo, Y. Lestari
This study aims to obtain cellulase enzymes from selected molds for microcrystalline cellulose preparation from ????-cellulose of kapok cortex. Alpha-cellulose was obtained by biodelignification, and the purified cellulase was obtained from the selected mold. The Microcrystalline cellulose obtained from enzymatic hydrolysis was then identified FTIR and DSC, followed by characterization of microcrystalline cellulose, Particle Size and Distribution Analysis (PSA), and Scanning Electron Microscope-Energy Dispersive X-ray (SEM-EDX), Loss on drying, pH, bulk density, tapped density, and flow rate. Biodelignification produced 14.88% ????-cellulose, Penicillium sp. the selected mold had the highest cellulase activity, with a cellulolytic index of 4.83. FTIR identification was similar to Avicel PH 101 with a melting point of 244.580°C. Loss on drying was 3.74%, pH was 7.0, particle size ranged from 13.06 to 196.79 ????m, bulk density and tapped density were 0.11 g/cm3 and 0.23 g/cm3, respectively flow rate character is quite good. SEM-EDX was showed that the morphological shape of the microcrystalline cellulose of the kapok cortex is elongated. Microcrystalline cellulose has shown a quite similar in character and can be furthered.
{"title":"Isolation of Cellulase from Selected Fungal Strains and Its Use for Manufacture Microcrystal Cellulose from Kapuk Cortex (Ceiba Pentandra (L.) Gaertn)","authors":"Mi'rajunnisa Mi'rajunnisa, H. Suryadi, Sutriyo Sutriyo, Y. Lestari","doi":"10.26554/sti.2023.8.2.227-234","DOIUrl":"https://doi.org/10.26554/sti.2023.8.2.227-234","url":null,"abstract":"This study aims to obtain cellulase enzymes from selected molds for microcrystalline cellulose preparation from ????-cellulose of kapok cortex. Alpha-cellulose was obtained by biodelignification, and the purified cellulase was obtained from the selected mold. The Microcrystalline cellulose obtained from enzymatic hydrolysis was then identified FTIR and DSC, followed by characterization of microcrystalline cellulose, Particle Size and Distribution Analysis (PSA), and Scanning Electron Microscope-Energy Dispersive X-ray (SEM-EDX), Loss on drying, pH, bulk density, tapped density, and flow rate. Biodelignification produced 14.88% ????-cellulose, Penicillium sp. the selected mold had the highest cellulase activity, with a cellulolytic index of 4.83. FTIR identification was similar to Avicel PH 101 with a melting point of 244.580°C. Loss on drying was 3.74%, pH was 7.0, particle size ranged from 13.06 to 196.79 ????m, bulk density and tapped density were 0.11 g/cm3 and 0.23 g/cm3, respectively flow rate character is quite good. SEM-EDX was showed that the morphological shape of the microcrystalline cellulose of the kapok cortex is elongated. Microcrystalline cellulose has shown a quite similar in character and can be furthered.","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":"44689449","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}
Pub Date : 2023-04-15DOI: 10.26554/sti.2023.8.2.160-169
S. Priatna, Yusuf Mathiinul Hakim, Sahrul Wibyan, Siti Sailah, R. Mohadi
This work reports the modification of West Java natural bentonite as an effective adsorbent for rhodamine B dye. The modification was finished by sodium intercalation at room temperature to get low-energy preparation. Characterization of bentonite-modified adsorbent was used SEM, XRD, FTIR, and BET analysis. The material pore size and surface area were increased by 0.303 nm and 178.710 m2/g on Na-bentonite. The adsorption mechanism conformed well with the Freundlich isotherm model and pseudo-second-order kinetics equations. The adsorption process by thermodynamic analysis was endothermic and advantageous. Under the optimum condition of pH 6 (confirmed by pHpzc), initial dye concentration of 125 mg/L, and the adsorbent dosage of 0.09 g for 65 minutes, the Na-bentonite has a larger adsorption capacity (Qm) of 142.86 mg/g, while the different adsorbent dosages of 0.11 g for 75 minutes, the adsorption capacity of natural bentonite (Qm) reaches 140.85 mg/g. This work provides a method for establishing a low-energy preparation adsorbent of bentonite-based on Na intercalant as a low-cost and valuable adsorbent for waste dye removal.
{"title":"Interlayer Modification of West Java Natural Bentonite as Hazardous Dye Rhodamine B Adsorption","authors":"S. Priatna, Yusuf Mathiinul Hakim, Sahrul Wibyan, Siti Sailah, R. Mohadi","doi":"10.26554/sti.2023.8.2.160-169","DOIUrl":"https://doi.org/10.26554/sti.2023.8.2.160-169","url":null,"abstract":"This work reports the modification of West Java natural bentonite as an effective adsorbent for rhodamine B dye. The modification was finished by sodium intercalation at room temperature to get low-energy preparation. Characterization of bentonite-modified adsorbent was used SEM, XRD, FTIR, and BET analysis. The material pore size and surface area were increased by 0.303 nm and 178.710 m2/g on Na-bentonite. The adsorption mechanism conformed well with the Freundlich isotherm model and pseudo-second-order kinetics equations. The adsorption process by thermodynamic analysis was endothermic and advantageous. Under the optimum condition of pH 6 (confirmed by pHpzc), initial dye concentration of 125 mg/L, and the adsorbent dosage of 0.09 g for 65 minutes, the Na-bentonite has a larger adsorption capacity (Qm) of 142.86 mg/g, while the different adsorbent dosages of 0.11 g for 75 minutes, the adsorption capacity of natural bentonite (Qm) reaches 140.85 mg/g. This work provides a method for establishing a low-energy preparation adsorbent of bentonite-based on Na intercalant as a low-cost and valuable adsorbent for waste dye removal.","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":"49612816","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}
Pub Date : 2023-04-15DOI: 10.26554/sti.2023.8.2.280-287
Amri Amri, A. Lesbani, R. Mohadi
Ni/Al layered double hydroxide and Ni/Al-graphene oxide composite materials were created using the coprecipitation method. The materials were successfully synthesized and prepared using XRD, FT-IR, and BET studies. The optimal pH as a result of malachite green dye adsorption is pH 4. The kinetics models of all materials follow the pseudo second order model. After being composited with graphene oxide, the maximum adsorption capacity of Ni/Al layered double hydroxide increased from 99.010 to 111.111 mg/g. All materials’ isotherm models adhere to the Langmuir isotherm model. The adsorption process was endothermic and spontaneous. The Ni/Al-graphene oxide composite material has a more stable structure than the Ni/Al layered double hydroxide. The regeneration procedure was repeated five times, and the Ni/Al-graphene oxide composite material did not show a significant decrease until the fifth cycle, when it dropped from 97.561 to 77.046%, however the Ni/Al layered double hydroxide material dropped rapidly from 85.00 to 5.667%.
{"title":"Malachite Green Dye Adsorption from Aqueous Solution using a Ni/Al Layered Double Hydroxide-Graphene Oxide Composite Material","authors":"Amri Amri, A. Lesbani, R. Mohadi","doi":"10.26554/sti.2023.8.2.280-287","DOIUrl":"https://doi.org/10.26554/sti.2023.8.2.280-287","url":null,"abstract":"Ni/Al layered double hydroxide and Ni/Al-graphene oxide composite materials were created using the coprecipitation method. The materials were successfully synthesized and prepared using XRD, FT-IR, and BET studies. The optimal pH as a result of malachite green dye adsorption is pH 4. The kinetics models of all materials follow the pseudo second order model. After being composited with graphene oxide, the maximum adsorption capacity of Ni/Al layered double hydroxide increased from 99.010 to 111.111 mg/g. All materials’ isotherm models adhere to the Langmuir isotherm model. The adsorption process was endothermic and spontaneous. The Ni/Al-graphene oxide composite material has a more stable structure than the Ni/Al layered double hydroxide. The regeneration procedure was repeated five times, and the Ni/Al-graphene oxide composite material did not show a significant decrease until the fifth cycle, when it dropped from 97.561 to 77.046%, however the Ni/Al layered double hydroxide material dropped rapidly from 85.00 to 5.667%.","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":"45697914","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}
Pub Date : 2023-04-15DOI: 10.26554/sti.2023.8.2.178-183
Barlin Oemar, A. Arifin, D. Bahrin, Astuti Astuti, D. Ramadhan, Muhammad Abil Rifqy, Muhammad Reza Tinambunan
This paper shows experimental study results on the thermophysical and stability of nanofluids of Titanium oxide (TiO2) dispersed in high-purity of Virgin Coconut Oil (VCO). Nanofluid samples that functioned as a lubricant were prepared by a two-step preparation method at different volume fractions (0.1, 0.3, and 0.5 vol.%) and different temperatures (28, 40, and 100°C). The dynamic viscosity and density were performed using Falling Ball Viscometer and Pycnometer, respectively. The sedimentation photograph method using a digital camera was applied to analyze the stability. A maximum dynamic viscosity enhancement of 62.78% was recorded for TiO2/VCO nanofluid with 0.5% nanoparticle volume fraction and at the temperature of 100°C). Whereas, the highest density improvement was recorded for TiO2/VCO nanofluid with 0.5% nanoparticle volume fraction. Freshly prepared nanofluids did not show any significant change in stability. However, a trivial phase separation appeared in the samples after 8 days. The results indicated that adding TiO2 nanoparticles increased the dynamic viscosity and density. It can be concluded that the volume in fraction has the effect to enhance the thermophysical stability of TiO2/VCO nanofluids.
{"title":"Experimental Investigation on Thermophysical and Stability Properties of TiO2/Virgin Coconut Oil Nanofluid","authors":"Barlin Oemar, A. Arifin, D. Bahrin, Astuti Astuti, D. Ramadhan, Muhammad Abil Rifqy, Muhammad Reza Tinambunan","doi":"10.26554/sti.2023.8.2.178-183","DOIUrl":"https://doi.org/10.26554/sti.2023.8.2.178-183","url":null,"abstract":"This paper shows experimental study results on the thermophysical and stability of nanofluids of Titanium oxide (TiO2) dispersed in high-purity of Virgin Coconut Oil (VCO). Nanofluid samples that functioned as a lubricant were prepared by a two-step preparation method at different volume fractions (0.1, 0.3, and 0.5 vol.%) and different temperatures (28, 40, and 100°C). The dynamic viscosity and density were performed using Falling Ball Viscometer and Pycnometer, respectively. The sedimentation photograph method using a digital camera was applied to analyze the stability. A maximum dynamic viscosity enhancement of 62.78% was recorded for TiO2/VCO nanofluid with 0.5% nanoparticle volume fraction and at the temperature of 100°C). Whereas, the highest density improvement was recorded for TiO2/VCO nanofluid with 0.5% nanoparticle volume fraction. Freshly prepared nanofluids did not show any significant change in stability. However, a trivial phase separation appeared in the samples after 8 days. The results indicated that adding TiO2 nanoparticles increased the dynamic viscosity and density. It can be concluded that the volume in fraction has the effect to enhance the thermophysical stability of TiO2/VCO nanofluids.","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":"42340986","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}
Pub Date : 2023-04-15DOI: 10.26554/sti.2023.8.2.245-251
Andriono Manalu, I. Manalu, M. Panjaitan, Ady Frenly Simanullang, Parlindungan Sitorus
Supercapacitors can be called electrostatic double-layer capacitors (EDLCs) or pseudo-capacitors based on their energy storage mechanism. Pseudo-capacitors with metal oxide electrodes that transmit electric charge offer great application power but low stability. This study aims to characterize trisodium citrate (TSC) modified NiCo2O4/rGO electrodes as a preliminary study for the NiCo2O4 nanoparticle pseudo-capacitor. The materials were characterized using SEM (Scanning Electron Microscopy), XRD (X-Ray Diffractometer), FT-Raman (Fourier Transform Raman Spectroscopy), and FTIR (Fourier Transform Infrared Spectroscopy). All of these analyses confirmed that NiCo2O4 was manufactured successfully using TSC. At XRD, the angles of 2????, namely 45.04 and 53.34°, matched the plane of the cubic phase nanorod crystals of NiCo2O4 with values of 400 and 511, respectively. In the Raman examination, the presence of rGO, which increased the crystallinity of NiCo2O4 nanoparticles, was confirmed. FTIR analysis indicated that the 1550-1600 cm−1 corresponds to a C=C functional group in an aromatic ring or a C=O ????-???? structure, and the wavenumber of 2300 cm−1 corresponds to the OH group in TSC, an alkanoate derivative. SEM analysis determined that NiCo2O4 nanoparticles with 1 mmol TSC are the ideal material for supercapacitor electrodes, as the structure is the most uniform, soft, and tidy. Further analysis is needed to confirm the stability of the modified material.
{"title":"Characterization of Synthesized NiCo2O4 with Trisodium Citrate for Supercapacitor Material: A Preliminary Study","authors":"Andriono Manalu, I. Manalu, M. Panjaitan, Ady Frenly Simanullang, Parlindungan Sitorus","doi":"10.26554/sti.2023.8.2.245-251","DOIUrl":"https://doi.org/10.26554/sti.2023.8.2.245-251","url":null,"abstract":"Supercapacitors can be called electrostatic double-layer capacitors (EDLCs) or pseudo-capacitors based on their energy storage mechanism. Pseudo-capacitors with metal oxide electrodes that transmit electric charge offer great application power but low stability. This study aims to characterize trisodium citrate (TSC) modified NiCo2O4/rGO electrodes as a preliminary study for the NiCo2O4 nanoparticle pseudo-capacitor. The materials were characterized using SEM (Scanning Electron Microscopy), XRD (X-Ray Diffractometer), FT-Raman (Fourier Transform Raman Spectroscopy), and FTIR (Fourier Transform Infrared Spectroscopy). All of these analyses confirmed that NiCo2O4 was manufactured successfully using TSC. At XRD, the angles of 2????, namely 45.04 and 53.34°, matched the plane of the cubic phase nanorod crystals of NiCo2O4 with values of 400 and 511, respectively. In the Raman examination, the presence of rGO, which increased the crystallinity of NiCo2O4 nanoparticles, was confirmed. FTIR analysis indicated that the 1550-1600 cm−1 corresponds to a C=C functional group in an aromatic ring or a C=O ????-???? structure, and the wavenumber of 2300 cm−1 corresponds to the OH group in TSC, an alkanoate derivative. SEM analysis determined that NiCo2O4 nanoparticles with 1 mmol TSC are the ideal material for supercapacitor electrodes, as the structure is the most uniform, soft, and tidy. Further analysis is needed to confirm the stability of the modified material.","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":"42527801","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}
Pub Date : 2023-04-15DOI: 10.26554/sti.2023.8.2.219-226
M. Syukur, Masitoh Suryaning Prahasiwi, Nurkhasanah Nurkhasanah, S. Yuliani, Y. Purwaningsih, E. Indriyanti
Profiling of chemical compounds on star anise extract and fractions showed the content and looked for active compounds. The main compounds in alkaloids, flavonoids, saponins, phenolics, and triterpenoid forms were identified based on phytochemical screening. FTIR and GC-MS analysis were used to purify the extract and fractions’ main compounds. After analyzing the main components of extract and fractions, a correlation was made between the total phenolic and flavonoid content. The total phenolic content was determined by adding folincalteau complexing solution converted to gallic acid equivalent (GAE), while the total flavonoid content was determined by AlCl3 complexing solution converted to Quercetin Equivalent (QE). The total phenolic yields for extract ethanol, n-hexane fraction, ethyl acetate fraction, and fraction ethanol were obtained at 106.45, 52.30, 93.46, and 148.97 mgGAE/g, respectively. Then the total flavonoid results were 107.45, 58.94, 148.99, 140.01 mgQE/g. The total content of phenolics and flavonoids illustrated the number of active compounds that have a role as free radical scavengers due to their group. Antioxidant activity was tested with 1,1-diphenyl-2-picrylhydrazyl (DPPH) on extracts and fractions, with the best IC50 results obtained in the ethanol fraction 0.416 mg/mL.
{"title":"Profiling of Active Compounds of Extract Ethanol, n-Hexane, Ethyl Acetate and Fraction Ethanol of Star Anise (Illicium verum Hook. f.) and Determination of Total Flavonoids, Total Phenolics and Their Potential as Antioxidants","authors":"M. Syukur, Masitoh Suryaning Prahasiwi, Nurkhasanah Nurkhasanah, S. Yuliani, Y. Purwaningsih, E. Indriyanti","doi":"10.26554/sti.2023.8.2.219-226","DOIUrl":"https://doi.org/10.26554/sti.2023.8.2.219-226","url":null,"abstract":"Profiling of chemical compounds on star anise extract and fractions showed the content and looked for active compounds. The main compounds in alkaloids, flavonoids, saponins, phenolics, and triterpenoid forms were identified based on phytochemical screening. FTIR and GC-MS analysis were used to purify the extract and fractions’ main compounds. After analyzing the main components of extract and fractions, a correlation was made between the total phenolic and flavonoid content. The total phenolic content was determined by adding folincalteau complexing solution converted to gallic acid equivalent (GAE), while the total flavonoid content was determined by AlCl3 complexing solution converted to Quercetin Equivalent (QE). The total phenolic yields for extract ethanol, n-hexane fraction, ethyl acetate fraction, and fraction ethanol were obtained at 106.45, 52.30, 93.46, and 148.97 mgGAE/g, respectively. Then the total flavonoid results were 107.45, 58.94, 148.99, 140.01 mgQE/g. The total content of phenolics and flavonoids illustrated the number of active compounds that have a role as free radical scavengers due to their group. Antioxidant activity was tested with 1,1-diphenyl-2-picrylhydrazyl (DPPH) on extracts and fractions, with the best IC50 results obtained in the ethanol fraction 0.416 mg/mL.","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":"44475783","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}
Pub Date : 2023-04-15DOI: 10.26554/sti.2023.8.2.265-279
A. O. Adeyemi, I. Adeleke, E. Akarawak
The Exponential Pareto (EP) model has been extended by applied and theoretical statisticians for wider applications and new knowledge using different techniques but the Weibull-X technique has not been considered. This article proposed a new extension of the EP model called the Weibull-Exponential Pareto (WEP) distribution to provide better modeling that fits real-life datasets and to explore the statistical theory of order statistics from the proposed distribution. Statistical properties investigated include the Shannon and Renyi entropies; the moments and moment generating function. Distribution of order statistics and the moment of order statistics were derived including the mean and variance of order statistics. WEP distribution has unimodal, decreasing, and increasing failure rates; and it can be negatively or positively skewed and approximately symmetric with the potential for fitting platykurtic, mesokurtic, and leptokurtic lifetime data. The parameters of the distribution were estimated using the method of maximum likelihood estimation (MLE), which was examined for consistency through a simulation study. The performance of the proposed distribution was investigated by application to flood peaks exceedances and some lifetime datasets from engineering. The results from data analysis using the R-software revealed that the WEP distribution has the potential to provide a superior model that fits the three data sets better than some notable existing distributions and previous extensions of the EP model in the literature. The statistical property of order statistics extended in the study established some important results that characterized some notable lifetime distributions in the literature.
{"title":"Extension of Exponential Pareto Distribution with the Order Statistics: Some Properties and Application to Lifetime Dataset","authors":"A. O. Adeyemi, I. Adeleke, E. Akarawak","doi":"10.26554/sti.2023.8.2.265-279","DOIUrl":"https://doi.org/10.26554/sti.2023.8.2.265-279","url":null,"abstract":"The Exponential Pareto (EP) model has been extended by applied and theoretical statisticians for wider applications and new knowledge using different techniques but the Weibull-X technique has not been considered. This article proposed a new extension of the EP model called the Weibull-Exponential Pareto (WEP) distribution to provide better modeling that fits real-life datasets and to explore the statistical theory of order statistics from the proposed distribution. Statistical properties investigated include the Shannon and Renyi entropies; the moments and moment generating function. Distribution of order statistics and the moment of order statistics were derived including the mean and variance of order statistics. WEP distribution has unimodal, decreasing, and increasing failure rates; and it can be negatively or positively skewed and approximately symmetric with the potential for fitting platykurtic, mesokurtic, and leptokurtic lifetime data. The parameters of the distribution were estimated using the method of maximum likelihood estimation (MLE), which was examined for consistency through a simulation study. The performance of the proposed distribution was investigated by application to flood peaks exceedances and some lifetime datasets from engineering. The results from data analysis using the R-software revealed that the WEP distribution has the potential to provide a superior model that fits the three data sets better than some notable existing distributions and previous extensions of the EP model in the literature. The statistical property of order statistics extended in the study established some important results that characterized some notable lifetime distributions in the literature.","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":"46245905","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}
Pub Date : 2023-04-15DOI: 10.26554/sti.2023.8.2.298-304
Raghad I. Sabri, Buthainah A. A. Ahmed
Fixed point (briefly FP ) theory is a potent tool for resolving several actual problems since many problems may be simplified to the FP problem. The idea of Banach contraction mapping is a foundational theorem in FP theory. This idea has wide applications in several fields; hence, it has been developed in numerous ways. Nevertheless, all of these results are reliant on the existence and uniqueness of a FP on some suitable space. Because the FP problem could not have a solution in the case of nonself-mappings, the idea of the best proximity point (briefly Bpp) is offered to approach the best solution. This paper investigates the existence and uniqueness of the Bpp of nonself-mappings in fuzzy normed space(briefly FN space) to arrive at the best solution. Following the introduction of the definition of the Bpp, the existence, and uniqueness of the Bpp are shown in a FN space for diverse fuzzy proximal contractions such as ?????? fuzzy proximal contractive mapping and ????h ????h - fuzzy proximal contractive mapping.
{"title":"Best Proximity Point Results in Fuzzy Normed Spaces","authors":"Raghad I. Sabri, Buthainah A. A. Ahmed","doi":"10.26554/sti.2023.8.2.298-304","DOIUrl":"https://doi.org/10.26554/sti.2023.8.2.298-304","url":null,"abstract":"Fixed point (briefly FP ) theory is a potent tool for resolving several actual problems since many problems may be simplified to the FP problem. The idea of Banach contraction mapping is a foundational theorem in FP theory. This idea has wide applications in several fields; hence, it has been developed in numerous ways. Nevertheless, all of these results are reliant on the existence and uniqueness of a FP on some suitable space. Because the FP problem could not have a solution in the case of nonself-mappings, the idea of the best proximity point (briefly Bpp) is offered to approach the best solution. This paper investigates the existence and uniqueness of the Bpp of nonself-mappings in fuzzy normed space(briefly FN space) to arrive at the best solution. Following the introduction of the definition of the Bpp, the existence, and uniqueness of the Bpp are shown in a FN space for diverse fuzzy proximal contractions such as ?????? fuzzy proximal contractive mapping and ????h ????h - fuzzy proximal contractive mapping.","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":"49401151","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}
Pub Date : 2023-04-15DOI: 10.26554/sti.2023.8.2.205-211
W. Alshanti, I. Batiha, Ahmad Alshanty, A. Zraiqat, I. Jebril, Ma’mon Ahmad Abu
In our current research article, based on a general configuration of a 3-step Peano kernel, new versions of integral inequality of Ostrowski’s type are developed for differentiable mappings that have second derivatives belong to L∞. Then we utilized these versions to generate new perturbed trapezoid like inequalities. These new perturbed trapezoid like inequalities are proposed with error bounds smaller than and similar to those reported by previous studies. Moreover, some of the obtained perturbed trapezoid like inequalities reveal the relationship between the Euler-Maclaurin summation and the trapezoidal rule. Finally, certain implementations to numerical composite quadrature rules are provided for completeness.
{"title":"Perturbed Trapezoid Like Inequalities","authors":"W. Alshanti, I. Batiha, Ahmad Alshanty, A. Zraiqat, I. Jebril, Ma’mon Ahmad Abu","doi":"10.26554/sti.2023.8.2.205-211","DOIUrl":"https://doi.org/10.26554/sti.2023.8.2.205-211","url":null,"abstract":"In our current research article, based on a general configuration of a 3-step Peano kernel, new versions of integral inequality of Ostrowski’s type are developed for differentiable mappings that have second derivatives belong to L∞. Then we utilized these versions to generate new perturbed trapezoid like inequalities. These new perturbed trapezoid like inequalities are proposed with error bounds smaller than and similar to those reported by previous studies. Moreover, some of the obtained perturbed trapezoid like inequalities reveal the relationship between the Euler-Maclaurin summation and the trapezoidal rule. Finally, certain implementations to numerical composite quadrature rules are provided for completeness.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68995017","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}
Pub Date : 2023-04-15DOI: 10.26554/sti.2023.8.2.321-329
F. Yanuar, Tasya Abrari, Izzati Rahmi HG, A. Zetra
The Open Unemployment Level (OUL) is the percentage of the unemployed to the total labor force. One of the provinces with the highest OUL score in Indonesia is West Java Province. If an object of observation is affected by spatial effects, namely spatial dependence and spatial diversity, then the regression model used is the Spatial Autoregressive (SAR) model. Quantile regression minimizes absolute weighted residuals that are not symmetrical. It is perfect for use on data distribution that is not normally distributed, dense at the ends of the data distribution, or there are outliers. The Spatial Autoregressive Quantile Regression (SARQR) is a model that combines spatial autoregressive models with quantile regression. This research used the data regarding OUR in West Java in 2020 from the Central Bureau of Statistics. This study develops to modeling the Open Unemployment Level in all province in Indonesia using modified spatial autoregressive model with the quantile regression approach. This study compares the estimation results based on SAR and SARQR models to obtain an acceptable model. In this study, it was found that the SARQR model is better than SAR at dealing with the problems of dependency and diversity in spatial data modeling and is not easily affected by the presence of outlier data.
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