WEYL’S THEOREM, TENSOR PRODUCT, FUGLEDE-PUTNAM THEOREM AND CONTINUITY SPECTRUM FOR k-QUASI CLASS A ∗ n OPERATORS

Ilmi Hoxha,Naim Latif Braha 대한수학회 2014 대한수학회지 Vol.51 No.5

An operator T ∈ L(H), is said to belong to k-quasi class A∗n operator if T∗k(|Tn+1|2/n+1 - |T∗|2)Tk≥O for some positive integer n and some positive integer k. First, we will see some properties of this class of operators and prove Weyl’s theorem for algebraically k-quasi class A ∗ n . Second, we consider the tensor product for k-quasi class A ∗ n , giving a necessary and sufficient condition for T ⊗ S to be a k-quasi class A ∗ n , when T and S are both non-zero operators. Then, the existence of a nontrivial hyperinvariant subspace of k-quasi class A ∗ n operator will be shown, and it will also be shown that if X is a Hilbert-Schmidt operator, A and (B ∗ ) −1 are k-quasi class A ∗ n operators such that AX = XB, then A ∗ X = XB ∗ . Finally, we will prove the spectrum continuity of this class of operators.

다중 사용자 온라인 게임 개발을 통한 소프트웨어 개발 교육

윤일미 ( Ilmi Yoon ),게리앵 ( Gary Ng ),권오영 ( Oh Young Kwon ) 한국실천공학교육학회 2012 실천공학교육논문지 Vol.4 No.2

WEYL'S THEOREM, TENSOR PRODUCT, FUGLEDE-PUTNAM THEOREM AND CONTINUITY SPECTRUM FOR k-QUASI CLASS A_n^* OPERATO

Hoxha, Ilmi,Braha, Naim Latif Korean Mathematical Society 2014 대한수학회지 Vol.51 No.5

An operator $T{\in}L(H)$, is said to belong to k-quasi class $A_n^*$ operator if $$T^{*k}({\mid}T^{n+1}{\mid}^{\frac{2}{n+1}}-{\mid}T^*{\mid}^2)T^k{\geq}O$$ for some positive integer n and some positive integer k. First, we will see some properties of this class of operators and prove Weyl's theorem for algebraically k-quasi class $A_n^*$. Second, we consider the tensor product for k-quasi class $A_n^*$, giving a necessary and sufficient condition for $T{\otimes}S$ to be a k-quasi class $A_n^*$, when T and S are both non-zero operators. Then, the existence of a nontrivial hyperinvariant subspace of k-quasi class $A_n^*$ operator will be shown, and it will also be shown that if X is a Hilbert-Schmidt operator, A and $(B^*)^{-1}$ are k-quasi class $A_n^*$ operators such that AX = XB, then $A^*X=XB^*$. Finally, we will prove the spectrum continuity of this class of operators.

Needs Analysis of Students’ Pro-Environmental Behavior for Climate Change Books

Diana Vivanti Sigit(Diana Vivanti Sigit ),Eka Putri Azrai(Eka Putri Azrai ),Ade Suryanda(Ade Suryanda ),Ilmi Zajuli Ichsan(Ilmi Zajuli Ichsan ),Michael B. Cahapay(Michael B. Cahapay ),Md. Mehadi Rahma 인간식물환경학회 2022 인간식물환경학회지 Vol.25 No.5

Background and objective: Climate change is a current issue that need to be solved by innovation in environmental education. However, efforts specifically to develop a teaching material based on the learning needs of the students related to climate change has not been given attention. This study aims to describe the Pro-Environmental Behavior (PEB) of students as basis for the development of an educational material to be known as Climate Change Book Series (CCBS-US). Methods: It entailed a descriptive research design and survey method, involving a sample of 642 students in Jakarta and Semarang, Indonesia. The data were treated using descriptive statistics. Data analysis using ANOVA test to see the significant of the difference between each group. Results: The results indicate that the university students’ PEB score is high while the high school students’ PEB score is moderate. The lowest average score is found in aspects related to efforts in reducing garbage and recycling. Details of average score were Junior high school students (74.49), senior high school students (66.28), Faculty of Math and Science university students (73.69), Non-Faculty Math and Science university students (72.27). Conclusion: It is along these inputs that the CCBS-US must be developed as a learning material in environmental education. It is hoped that the results of this study, the developed CCBS-US can significantly empower students' PEB scores in classroom learning.

Lipase-producing Filamentous Fungi from Non-dairy Creamer Industrial Waste

Triyaswati, Desty,Ilmi, Miftahul The Korean Society for Microbiology and Biotechnol 2020 한국미생물·생명공학회지 Vol.48 No.2

Lipase-producing fungi have been isolated from environments containing lipids. The non-dairy creamer industrial waste has a high amount of lipids so it is a potential source for the isolation of lipase-producing fungi. However, the study of fungi that secrete lipase from this industrial waste has not been reported. The purpose of this study was to obtain lipase-producing filamentous fungi from non-dairy creamer industrial waste. Mineral salt and potato dextrose agar were used as media for the isolation process. The qualitative screening was conducted using phenol red agar medium and the quantitative screening using broth medium containing glucose and olive oil. Isolates producing the highest amounts of lipase were identified with molecular methods. We found that 5 out of 19 isolated filamentous fungi are lipase producers. Further analysis showed that isolate Ms.11 produced the highest amount of lipase compared to others. Based on ITS sequence Ms.11 was identified as Aspergillus aculeatus. The lipase activity in medium containing 1% glucose + 1% olive oil at pH 7.0 and 30℃ after 96 and 120 h of incubation was 5.13 ± 0.30 U/ml and 5.22 ± 0.59 U/ml, respectively. The optimum lipase activity was found at pH 7.0, 30℃ and using methanol or ethanol in the reaction tube. Lipase was more stable at 20-30℃ and maintained 85% of its activity. It was concluded that isolate Ms.11 is a potential source of lipase that catalyzes transesterification reactions. Further studies are required to optimize lipase production to make the strain suitable for industry purposes.

Higher-Order Thinking Skills of High School and College Students on Flood Mitigation

Henita Rahmayanti,Ilmi Zajuli Ichsan,Wiwin Pramita Arif,Rika Sa’diyah,Irwandani,Nur Fadli Hazhar Fachrial 인간식물환경학회 2022 인간식물환경학회지 Vol.25 No.1

Background and objective: Numerous flood disaster events encourage mitigation efforts. One of the efforts is educationto high school and college students through a project-based learning (PjBL) model during COVID-19. The PjBL innovationcan be developed by teachers with a formulation that integrates it with learning media and higher-order thinking skills(HOTS) as the measured parameter. Methods: The research goal is to analyze high school and college students’ HOTS, learning media, and the PjBL model. Learning method employed in the research is descriptive. The HOTS instrument was developed according to Anderson'staxonomy to measure the ability of high school and college students. Results: The research results indicated that the HOTS score of the high school and college students was very low at 28.29and 46.01, respectively. The research results suggested an improvement of the HOTS by developing a learning medium toenhance students’ HOTS. In addition, the results of the study also showed that the role of teachers and lecturers was veryimportant in facilitating the use of learning media. Conclusion: Teachers and lecturers in this context must be able to facilitate the formation of loving behavior towards theenvironment. The learning media will be a content supplement for the primary, secondary, and higher education in learningflood concepts. Based on the results, the conclusion is that high school and college students’ HOTS score is in a lowcategory and all aspects of learning media can be integrated with PjBL.

Lipase-producing Filamentous Fungi from Non-dairy Creamer Industrial Waste

Desty Triyaswati,Miftahul Ilmi 한국미생물·생명공학회 2020 한국미생물·생명공학회지 Vol.48 No.2

Lipase-producing fungi have been isolated from environments containing lipids. The non-dairy creamer industrial waste has a high amount of lipids so it is a potential source for the isolation of lipase-producing fungi. However, the study of fungi that secrete lipase from this industrial waste has not been reported. The purpose of this study was to obtain lipase-producing filamentous fungi from non-dairy creamer industrial waste. Mineral salt and potato dextrose agar were used as media for the isolation process. The qualitative screening was conducted using phenol red agar medium and the quantitative screening using broth medium containing glucose and olive oil. Isolates producing the highest amounts of lipase were identified with molecular methods. We found that 5 out of 19 isolated filamentous fungi are lipase producers. Further analysis showed that isolate Ms.11 produced the highest amount of lipase compared to others. Based on ITS sequence Ms.11 was identified as Aspergillus aculeatus. The lipase activity in medium containing 1% glucose + 1% olive oil at pH 7.0 and 30℃ after 96 and 120 h of incubation was 5.13 ± 0.30 U/ml and 5.22 ± 0.59 U/ml, respectively. The optimum lipase activity was found at pH 7.0, 30℃ and using methanol or ethanol in the reaction tube. Lipase was more stable at 20−30℃ and maintained 85% of its activity. It was concluded that isolate Ms.11 is a potential source of lipase that catalyzes transesterification reactions. Further studies are required to optimize lipase production to make the strain suitable for industry purposes.

Economic Performance: Leading Sector, Economic Structure and Competitiveness of Export Commodities

Adi WIJAYA,Zainal ILMI,Dio Caisar DARMA 한국유통과학회 2020 Asian Journal of Business Environment (AJBE) Vol.10 No.3

Purpose: The purpose of this study is for the leading sector, a pattern of shifting structure of the economic sector, and community export competitiveness on the economy Malinau Regency. Research design, data, and methodology: The type of data used is secondary data with a quantitative approach of 2009-2018. The study data used Location Quotient (LQ), Shift Share Analysis (SSA), and Revealed Comparative Advantage (RCA) analysis tools. Results: There are 6 leading sectors: agriculture; electricity, gas, and clean water; building and construction; trade, hotels, and restaurants. That has been classified has changed the economic structure of the Malinau Regency from the secondary sector to the tertiary and primary sectors in 10 years. While, community export competitiveness of the Malinau Regency through RCA Analysis, see if the export products of coal and excavation (types A, B, C) are shown to have a higher comparative advantage with comparative advantage. This shows that only a few commodities that can provide the good performance of export. Conclusions: Analysis of economic growth in the Malinau Regency after regional autonomy shows that there has been a shift in the economic structure of the economy which is dominated by the structure of the primary sector.

Genetic Diversity of Amylomyces rouxii from Ragi tapai in Java Island Based on Ribosomal Regions ITS1/ITS2 and D1/D2

Delva Ega,Arisuryanti Tuty,Ilmi Miftahul 한국균학회 2022 Mycobiology Vol.50 No.2

Amylomyces rouxii is commonly found as amylolytic fungi in tapai fermentation. However, its diversity is rarely reported despite being often used for food production in Southeast Asia. This research aims to analyze the genetic diversity and the distribution pattern of A. rouxii from Ragi tapai in Java Island, Indonesia. We isolated the fungus from samples obtained from Ragi tapai producing centers in Bandung, Sumedang, Muntilan, Blora, Yogyakarta, and Bondowoso. The obtained isolates were molecularly identified based on the ribosomal regions ITS1/ITS2 and D1/D2, then analyzed for phylogenetic tree reconstruction, genetic distance, genetic variation, and haplotype networking. Six isolates showed specific morphological traits of A. rouxii. However, phylogenetic tree reconstruction on the ribosomal genes showed that the isolates were grouped into two different clades related to two species. Clade A included BDG, SMD, and MTL isolates related to A. rouxii, whereas clade B included YOG, BLR, and BDS isolates related to Mucor indicus. The genetic distances between clades for ITS1/ITS2 and D1/D2 were 0.6145 and 0.1556, respectively. In conclusion, we confirmed the genetic diversity of molds from Ragi tapai in Java Island and showed that the isolates are not only related to A. rouxii as reported before.

Optimization of Medium for Lipase Production from Zygosaccharomyces mellis SG1.2 Using Statistical Experiment Design

( Marisa Dian Pramitasari ),( Miftahul Ilmi ) 한국미생물 · 생명공학회 2021 한국미생물·생명공학회지 Vol.49 No.3

Lipase (triacylglycerol lipase, EC 3.1.1.3) is an enzyme capable of hydrolyzing triacylglycerol, to produce fatty acids and glycerol and reverse the reaction of triacylglycerol synthesis from fatty acids and glycerol through transesterification. Applications of lipase are quite widespread in the industrial sector, including in the detergent, paper, dairy, and food industries, as well as for biodiesel synthesis. Lipases by yeasts have attracted industrial attention because of their fast production times and high stability. In a previous study, a lipase-producing yeast isolate was identified as Zygosaccharomyces mellis SG1.2 and had a productivity of 24.56 U/mg of biomass. This productivity value has the potential to be a new source of lipase, besides Yarrowia lypolitica which has been known as a lipase producer with a productivity of 0.758 U/mg. Lipase production by Z. mellis SG1.2 needs to be increased by optimizing the production medium. The aims of this study were to determine the significant component of the medium for lipase production and methods to increase lipase production using the optimum medium. The two methods used for the statistical optimization of production medium were Taguchi and RSM (Response Surface Methodology). The data obtained were analyzed using Minitab 18 and SPSS 23 software. The most significant factors which affected lipase productivity were olive oil and peptones. The optimum medium composition consisted of 1.02% olive oil, 2.19% peptone, 0.05% MgSO₄·7H₂O, 0.05% KCl, and 0.2% K₂HPO₄. The optimum medium was able to increase the lipase productivity of Z. mellis SG1.2 to 1.8-fold times the productivity before optimization.