15 research outputs found
Pengembangan Modul Matematika Berbasis Matematika Realistik untuk Kelas VII SMP Semester I
Tujuan dari penelitian ini adalah untuk mengembangkan suatu desain bahan ajar pembelajaran berbentuk modul yang efektif untuk memfasilitasi proses pembelajaran matematika peserta didik kelas VII SMP Semester I. Modul Matematika ini dibuat berdasarkan hasil analisis kebutuhan terhadap kompetensi matematika yang seharusnya dimiliki oleh peserta didik kelas VII SMP. Alat pengambilan data berupa angket pertanyaan untuk guru sekolah. Prosedur penelitian diadaptasi dari model pengembangan instruksional (MPI) M. Atwi Suparman yang terdiri dari beberapa langkah, yaitu: mengidentifikasi kebutuhan dan menulis tujuan instruksional, melakukan analisis intruksional, mengidentifikasi perilaku dan karakteristik awal peserta didik, menulis tujuan instruksional khusus, Â menyusun alat penilaian hasil belajar, menyusun strategi instruksional, mengembangkan bahan instruksional, melaksanakan evaluasi formatif. Temuan penelitian yaitu dihasilkan suatu bahan ajar berbentuk modul yang sesuai dengan tujuan pembelajaran matematika peserta didik kelas VII SMP pada semester
Barriers for implementing reverse logistics in the construction sectors
Purpose: This paper aims to identify the barriers to implementing Reverse Logistics in the construction sector and rank the barriers between the stakeholder, the phase in the project life cycle, and the strategic factors on the emergence of obstacles in implementing reverse logistics. Design/methodology/approach: This research began by identifying barriers re- verse logistics through a systematic literature review. The method used in the systematic literature review was the PRISMA method. Next, the identification of barriers was assessed for their influence on successful reverse logistics implementation by the expert using a questionnaire instrument. The rating scale used was a Likert scale of 1 (greatly hinder the implementation of reverse logistics) to 5 (not significantly hinder the implementation of reverse logistics). Finally, the results of the expert assessment were used to rank barriers using TOPSIS. Findings: There are 38 barriers in this study, classified as market and competitor factors, policy factors, supply chain factors, economic factors, knowledge-related factors, government support factors, and operational factors. The classification of barriers based on the project life cycle aims to increase stakeholder collaboration on reverse logistics performance issues. The results of this study indicate that the lack of government support for the implementation of RL (GS1) is the obstacle with the highest rank. These barriers are related to government support factors and arise in the green initiation phase of the project life cycle approach. The governmentâs role as regulator and project owner will overcome GS1 barriers. Research limitations/implications: The limitation in the scope of this research is specific to the construction sector in developing countries, particularly Indonesia. The object of construction in this study is the case of the Penjagaan-Losari highway project. Further research that examines barriers based on the project life cycle by entering the company scale or studying the relationship between barriers can also be done. Practical implications: This study provides an analysis to stakeholders about the barriers in implementing reverse logistics. The ranking results become a reference for relevant stakeholders in developing a successful strategy for implementing reverse logistics and the PLC approach phases as a guideline for implementing the established strategy. Social implications: The stakeholder of the construction project has to learn with reverse logistics barriers to improve reverse logistics performance. Originality/value: This study analyzed reverse logistics implementation barriers in the construction sector in developing countries. The majority of research on reverse logistics implementation barriers examined the manufacturing sector in developed countries. This study also identifies barriers that show the relationship between barrier emergence in the project life cycle approach and stakeholders responsible for addressing barriers and associated problems. Previous research only identified obstacles based on stakeholder points of view and strategic factors in the implementation of reverse logistics. The drawback from the point of view of previous research is the difficulty of determining appropriate improvement efforts. Identifying barriers using a process-based approach such as the project life cycle will improve previous research weaknessesPeer Reviewe
Reverse Logistics Performance Indicators for the Construction Sector: A Building Project Case
While the performance evaluation of reverse logistics (RL) practices in the construction sector is crucial, it is seemingly limited compared to that in the manufacturing sector. As the project life cycle in the construction sector is typically long, effective coordination among the stakeholders is needed to integrate RL into each phase of the project life cycle. This paper proposes a new model of RL for the construction industry, incorporating the dimensions, elements, and, most importantly, indicators needed for the evaluation of RL performance. The model was initially derived from the extant literature. It was then refined through (1) focus group discussion, by which suggestions pertinent to the proposed model were collated from academics and practitioners, and (2) judgments by academics and practitioners to validate the model. The validated model includes 21 indicators to measure RL performance, spanned throughout the green initiation, green design, green material management, green construction, and green operation and maintenance phases. The paper offers a new method for how RL can be adopted in the construction industry by proposing an innovative model that will benefit stakeholders in the construction industry
PERENGKAHAN KATALITIK METIL ESTER DARI MINYAK LIMBAH CAIR PABRIK MINYAK KELAPA SAWIT DENGAN KATALIS Cr/Mo/HZA DAN Ni/Mo/HZA
The proposed catalytic cracking technology leads to the production of hydrocarbons that are present in variousfractions of gasoline, kerosene and diesel. In this study, the methyl ester was converted by catalytic cracking using catalyst Cr / Mo / HZA and Ni / Mo / HZA. Preparation of catalyst Cr / Mo / HZA was performed by soaking the natural zeolite powder (ZA) with HCl. The catalyst of HZA was refluxed by (NH4)Mo7O24.4H2O, then dried to obtain the catalyst of Mo/HZA. Futhermore,catalyst of Mo / HZA was refluxed by Cr (NO3) 3.9H2O. The catalyst pruduct of Cr / Mo /HZA was calcined at 500ÂșC. Catalysts Ni/Mo/ HZA was obtained through the same procedure by replacing Cr (NO3)3.9H2O with NiCl2.6H2O. Cracking was done by refluxing a methyl ester of oil residu slude waste (POME) with 1.5 g catalyst Cr / Mo / HZA and catalyst Ni / Mo / HZA at 350-380ÂșC . Results of the reflux were analyzed by GC-MS. The products of cracking of catalysts Cr / Mo / HZA were hydrocarbons that wasfractions of keroseneof 31.35%, and diesel fraction of 10.16%. While the product catalyst of Ni / Mo / HZA were 0.33% gas fractions,10.63% fractions gasoline and 11.02%fractions kerosene. The density was similar to densities ofgasoline and kerosene, the viscosity was similar to kerosene, acid number was about two times of acid numbers of gasoline and kerosene while water content was still higher than that of gasoline and kerosene.Keywords: Methyl ester, catalytic cracking, palm oil, gasoline, kerosen
PERENGKAHAN KATALITIK METIL ESTER DARI MINYAK LIMBAH CAIR PABRIK MINYAK KELAPA SAWIT DENGAN KATALIS Cr/Mo/HZA DAN Ni/Mo/HZA
The proposed catalytic cracking technology leads to the production of hydrocarbons that are present in variousfractions of gasoline, kerosene and diesel. In this study, the methyl ester was converted by catalytic cracking using catalyst Cr / Mo / HZA and Ni / Mo / HZA. Preparation of catalyst Cr / Mo / HZA was performed by soaking the natural zeolite powder (ZA) with HCl. The catalyst of HZA was refluxed by (NH4)Mo7O24.4H2O, then dried to obtain the catalyst of Mo/HZA. Futhermore,catalyst of Mo / HZA was refluxed by Cr (NO3) 3.9H2O. The catalyst pruduct of Cr / Mo /HZA was calcined at 500ÂșC. Catalysts Ni/Mo/ HZA was obtained through the same procedure by replacing Cr (NO3)3.9H2O with NiCl2.6H2O. Cracking was done by refluxing a methyl ester of oil residu slude waste (POME) with 1.5 g catalyst Cr / Mo / HZA and catalyst Ni / Mo / HZA at 350-380ÂșC . Results of the reflux were analyzed by GC-MS. The products of cracking of catalysts Cr / Mo / HZA were hydrocarbons that wasfractions of keroseneof 31.35%, and diesel fraction of 10.16%. While the product catalyst of Ni / Mo / HZA were 0.33% gas fractions,10.63% fractions gasoline and 11.02%fractions kerosene. The density was similar to densities ofgasoline and kerosene, the viscosity was similar to kerosene, acid number was about two times of acid numbers of gasoline and kerosene while water content was still higher than that of gasoline and kerosene.Keywords: Methyl ester, catalytic cracking, palm oil, gasoline, kerosen
Pelepasan Na-Diklofenak Sistem Niosom Span 20-Kolesterol Dalam Basis Gel HPMC
Tujuan dari penelitian ini adalah menentukan pelepasan Na-diklofenak dalam sistem niosom (Na-diklofenak : Span 20: kolesterol dalam perbandingan Molar 1:6:6) dari basis gel HPMC 4000. Penelitian ini, menggunakan dua formula; formula I adalah gel yang mengandung Na-diklofenak tanpa sistem niosom dan formula II adaluh gel yang mengandung Na-diklofenak dalam sistem niosom. Hasil penelitian menunjukkan bahwa Na-diklofenak dalam sistem niosom mempengaruhi pH dan kapasitas penyebaran sediaan. Na-diklofenak dalam sistem niosom meningkatkan pH sediaan, formula II memiliki pH (6,57 ± 0,02) lebih. tinggi dari formula I (5,94 ± 0,05). Kapasitas penyebaran sediaan formula II (7,6 ± 0,2 cm) lebih besar dari formula I (6,1 + 0,1 cm). Uji pelepasan menggunakan sel difusi ditutup dengan membran selofan, medium uji dapar fosfat salin pH 7,4 ± 0,05 serta suhu 32 ± 0,5°C selama 6 jam. Fluks pelepasan Na-diklofenak dari basis gel HPMC 4000 pada formula I dan formula Tl berturut-turut sebesar 155,6201 ± 4,9729 ”glcm2/menitœ dan 49,0925 ± 0,8684 ”glcm2/menitœ. Hasil uji statistik menggunakan Independent Sample T-test dengan α = 0,05 diketahui bahwa pelepasan Na-diklofenak dalam sistem uiosom dari basis gel HPMC 4000 lebih rendah dibandingkan pelepasan Na-diklofenak tanpa sistem niosom
Skrining Kapang Aspergillus Spp. Penghasil Aflatoksin pada Jagung Pipilan di Daerah Bekasi, Jawa Barat
Aflatoksin merupakan senyawa metabolit sekunder dari kapang Aspergillus flavus dan Aspergillus parasiticus yang dapat mengontaminasi bahan pangan atau pakan sehingga berbahaya bagi kesehatan hewan dan manusia. Kontaminasi kapang penghasil aflatoksin banyak ditemukan pada bahan pangan dan pakan yang berasal dari produk pertanian. Jagung merupakan salah satu produk pertanian yang mudah terkontaminasi oleh kapang penghasil aflatoksin. Penelitian ini bertujuan untuk memperoleh isolat kapang Aspergillus spp. penghasil aflatoksin pada jagung pipilan yang dijual di sekitar Bekasi, Jawa Barat. Isolasi kapang dilakukan menggunakan metode dilution plating pada medium Dichloran-Glycerol. Hasil penelitian memperoleh 12 isolat kapang, dengan warna koloni hijau (J1, J2, J3, J4, J5, J6, J7, J9, J10, J12), hitam (J11), dan jingga (J8). Identifikasi dilakukan dengan cara mengamati morfologi kapang secara makroskopik dan mikroskopik pada medium Malt Extract Agar. Isolat kapang yang diduga memiliki kemiripan dengan A. flavus berjumlah 6 isolat, yaitu J1, J2, J4, J6, J10, dan J12. Selanjutnya dilakukan uji konfirmasi menggunakan medium selektif Aspergillus flavus dan parasiticus Agar. Terdapat 2 isolat kapang, yaitu J1 dan J4, yang menunjukkan pigmentasi sebalik koloni berwarna pada medium selektif AFPA. Isolat kapang yang ditemukan pada jagung pipilan diharapkan dapat memberikan informasi kepada petani dan peternak mengenai jenis kapang yang dapat menyebabkan kontaminasi pada jagung, sehingga mereka dapat menjaga dan meningkatkan kualitas jagung untuk mengurangi kerugian dalam bidang ekonomi dan kesehatan
SKRINING KAPANG Aspergillus spp. PENGHASIL AFLATOKSIN PADA JAGUNG PIPILAN DI DAERAH BEKASI, JAWA BARAT
Abstrak
Aflatoksin merupakan senyawa metabolit sekunder dari kapang Aspergillus flavus dan Aspergillus parasiticus yang dapat mengontaminasi bahan pangan atau pakan sehingga berbahaya bagi kesehatan hewan dan manusia. Kontaminasi kapang penghasil aflatoksin banyak ditemukan pada bahan pangan dan pakan yang berasal dari produk pertanian. Jagung merupakan salah satu produk pertanian yang mudah terkontaminasi oleh kapang penghasil aflatoksin. Penelitian ini bertujuan untuk memperoleh isolat kapang Aspergillus spp. penghasil aflatoksin pada jagung pipilan yang dijual di sekitar Bekasi, Jawa Barat. Isolasi kapang dilakukan menggunakan metode dilution plating pada medium Dichloran-Glycerol. Hasil penelitian memperoleh 12 isolat kapang, dengan warna koloni hijau (J1, J2, J3, J4, J5, J6, J7, J9, J10, J12), hitam (J11), dan jingga (J8). Identifikasi dilakukan dengan cara mengamati morfologi kapang secara makroskopik dan mikroskopik pada medium Malt Extract Agar. Isolat kapang yang diduga memiliki kemiripan dengan A. flavus berjumlah 6 isolat, yaitu J1, J2, J4, J6, J10, dan J12. Selanjutnya dilakukan uji konfirmasi menggunakan medium selektif Aspergillus flavus dan parasiticus Agar. Terdapat 2 isolat kapang, yaitu J1 dan J4, yang menunjukkan pigmentasi sebalik koloni berwarna pada medium selektif AFPA. Isolat kapang yang ditemukan pada jagung pipilan diharapkan dapat memberikan informasi kepada petani dan peternak mengenai jenis kapang yang dapat menyebabkan kontaminasi pada jagung, sehingga mereka dapat menjaga dan meningkatkan kualitas jagung untuk mengurangi kerugian dalam bidang ekonomi dan kesehatan.
Abstract
Aflatoxin is a secondary metabolite secreted by the mold Aspergillus flavus and Aspergillus parasiticus that may contaminate food or feed so harmful to human and animal health. Contamination of aflatoxin-producing mold is commonly found in food and feed which derived from agricultural products. Corn is one of the agricultural products that are easily contaminated by aflatoxin-producing mold. The study aims to isolate the aflatoxin-producing mold Aspergillus spp. in stripped corn vend around Bekasi, West Java. The isolation was conducted by using the method of dilution plating on Dichloran-Glycerol medium. The study obtained 12 isolates of mold, with green colony color (J1, J2, J3, J4, J5, J6, J7, J9, J10, J12), black (J11), and jingga (J8). Identification was conducted by observing the morphology of mold on Malt Extract Agar macroscopically and microscopically. The isolates that allegedly have similarities to A. flavus are J1, J2, J4, J6, J10, and J12. Furthermore, a confirmatory test was preceed by using a selective medium of Aspergillus flavus and parasiticus agar. There are 2 isolates of molds, J1 and J4, which showed yellowish jingga pigmentation like the positive control of A. flavus. The isolates of mold found in the stripped corn may provide information to farmers and breeders about the type of mold that can cause contamination in corn, so that they can anticipate in advance and improve the quality of the corn to reduce losses in economic and health perspectives