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STUDY ON THE STABILITY OF TRIVALENT CATIONS GADOLINIUM (Gd) DOPED FERRIC OXIDE (Fe2O3) THROUGH ATOMISTIC MODELING
Get PDFThis research is aimed to study the stability of the structure Fe2O3 doped with trivalent cations Gadolinium (Gd) into compound Fe1-xGdxO2-δ through atomistic modeling and Bond Valence Sum (BVS) calculations. Short range potential used in this study was Buckingham potential. Result of geometry optimization at constant pressure shown the more of the concentration and the size of substituting dopant of ferric oxide (Fe2O3)increase, the more positive the lattice energy of the doped structure is, so that the stability of the doped Fe2O3 structure decreases
Kendala Calon Pendidik Dalam Membuat Soal Pilihan Ganda Higher Order Thinking (Hot)
Get PDFThis study shows the causes of sociology education students' difficulties in making higher order thinking (HOT) tests. The method applied is the mix method through FGD data collection and questionnaires. The results showed that it was difficult for students to make HOT questions because 1) it was challenging to create stimulus questions, 2) lack of understanding of sociology material, 3) lack of mastery of Bloom's taxonomy application, 4) insufficient learning time, and 5) lecturer explanations were not good. Therefore, recommendations for effective learning improvement are needed, including using the principle of discovery learnin
Analysis of the Effect of Changes in Pitch Ratio and Number of Blades on Cavitation on CPP
Get PDFCavitation is a detrimental phenomenon to ship operations because it causes many losses. It caused some effects i.e decreased propeller efficiency, damaged propeller material, lower ship speed, vibration, and extreme noises. In that regard, this research conducts cavitation analysis on controllable pitch propeller (CPP) by varying number of blade i.e. 3, 4 and 5 blades; diameter i.e. 30, 40 cm and 50 cm; also pitch i.e 0.4, 0.6 and 0.8. The research method is carried out by the author in this study by conducting a simulation method based on the CFD approach. The simulation process consists of 3 stage-post processor, solver manager, and post-processor. From the simulation based on the CFD approach result, it was found that propeller rotation has an effect on the pressure ratio value. As the propeller rotation increase, the value of the pressure ratio will increase as well. The value of the pressure ratio in propeller design affects the cavitation area that occurs in the propeller. The percentage of the cavitation area on the propeller has an increasing tendency with the number of blades, rotation, and pitch. On the propeller with diameter 300 mm, 3 blades, pitch 0.8 at rotation 125 rpm no indication of cavitation, then it increases to 1.41% at rotation 175 rpm and keeps getting higher at rotation 225 to be 4.22% from total propeller expanding area. Whereas at rotation 225 rpm and pitch 0.4 is 3.38 %, then it becomes 3.85 % at pitch 0.6, which is getting bigger at pitch 0.8 that is 4.22 %
Success Factor Analysis of Multiple Project Management
Get PDFPT XYZ is one of the largest manufacturing industry companies in Indonesia, that using multiple project management. Several concurrent projects existed, or also referred as multiple project management. Multiple project often cause several problems, such as the long duration of the project because of wrong determining priorities and limited resources. These problems certainly affect the success of the project in general. The success of the project is measured by the project iron triangle, that is budget, quality and time. Success of a project is important, and many research has been done to determine the project success factors. However, there is still limited research related to multiple projects. This is exploratory research, and initial stage where researchers will determine the factors that support the success of multiple projects. Following the variable identification from literature study, a survey was conducted. This research use exploratory factor analysis (EFA) and mean vs standard deviation analysis. Results of the study, success factors of multiple projects formed six factors including communication, organizational, technical, external, resource, and project factors. As a recommendation for the company, which factors are significant are seen from the results of the mean analysis, with the highest significance results are : (1) Material availability; (2) Realistic planning; and (3) Manager's competenc
Uji Resolusi Tomografi Seismik Waktu Tempuh Lokal Menggunakan Dua Input Model Sintetik
Get PDFUji resolusi dalam tomografi seismik telah diterapkan secara luas pada berbagai skala. Uji tersebut digunakan untuk mengetahui kehandalan data seismik yang digunakan pada suatu area penelitian. Checkerboard resolution test (CRT) merupakan salah satu teknik uji resolusi yang diterapkan secara luas pada data tomografi seismik. Uji resolusi dilakukan untuk mengetahui secara spasial area mana saja yang bisa diinterpretasi dari suatu tomogram seismik. Pada penelitian ini akan menguji resolusi dengan input model CRT dan Non-CRT. Area yang memiliki kemiripan pola antara input model dan hasil inversinya menunjukkan area tersebut bisa diinterpretasi baik secara geologi maupun dari properti fisika batuannya. Pada uji resolusi model Non-CRT juga ditambahkan random noise untuk mengetahui sejauh mana pengaruh noise terhadap data seismik. Hasil uji resolusi pada kedua input model tersebut menunjukan konsistensi pada area-area yang bisa diinterpretasi ataupun tidak. Hal ini menunjukkan data seismik yang digunakan pada penelitian ini memiliki kualitas yang cukup baik sehingga hasil studi tomografinya bisa menjelaskan kondisi geologi di bawah permukaanny
Influence of Leadership, Loyalty, and Followership on Team Performance of P.T. Gaharu Galangan International
Get PDFMany factors are deemed influencing team or group performance. This research identifies influence of variables of leadership, followership and loyalty on team performance. This research is quantitative research on path analysis by using SPSS program. The result is loyalty and followers don’t have direct positive effect on team performance, but through leadership variable as intervening variable. Leadership variable has direct positive effect on team performance and loyalty, and followership variable has direct positive effect on leadership variable
Skrining Senyawa Metabolit Sekunder Ekstrak Metanol Biji Alpukat (Persea Americana Mill.) Asal Pulau Timor
Get PDFAvocados (Persea americana Mill.) have many benefits for traditional medicine especially in East Nusa Tenggara. The purpose of this study was to analyze the secondary metabolite compounds contained in avocado seeds and to identify groups compounds in avocado seeds extract. The research method used was maceration of samples for 3 days and continued with phytochemical dan FT-IR test. The result showed that methanol extract of avocado seeds contains phytochemicals based on test result of secondary metabolites, the alkaloids, flavonoids, steroids, terpenoids, saponins and tannins. While the results of FT-IR analysis showed the presences of OH, CH, C=C, and C-O groups
Perancangan Inovasi Display Sepatu Fleksibel untuk Meningkatkan Efisiensi bagi Kebutuhan Sentra UKM
Get PDFSentra UKM Merr membutuhkan inovasi pada display alas kaki karena adanya beberapa faktor yang menyebabkan produk tersebut tidak dilihat oleh para pengunjung, salah satunya adalah penataan dan bentuk display yang tidak efisien sehingga menyebabkan produk alas kaki kurang menarik. Oleh karena itu, penulis melakukan inovasi display alas kaki yang fleksibel untuk meningkatkan efisiensi penggunaannya. Metode yang dilakukan penulis adalah lima tahap desain menurut Henry Ford Learning Institute, yaitu understanding, observe, ideate, prototype, dan test. Berdasarkan lima tahapan desain tersebut, dirancanglah display alas kaki dengan konstruksi tertentu agar dapat mengubah bentuk display untuk disesuaikan dengan kebutuhan pengguna
Penentuan Rekomendasi Standar Track Quality Index (TQI) untuk Kereta Semicepat di Indonesia (Studi Kasus : Surabaya - Cepu)
Get PDFPerkembangan transportasi saat ini merupakan sebuah hal yang tidak dapat dihindari sebagai konsekuensi dari tuntutan masyarakat yang memerlukan sebuah moda transportasi yang aman, handal, dan tepat waktu. Kereta semicepat dengan kecepatan maksimal 160 km/jam pada jalur eksisting utara (lintas Surabaya-Jakarta) yang kecepatan maksimal di jalur tersebut masih mencapai 120 km/jam hadir sebagai salah satu solusi yang digagas pemerintah untuk menyelesaikan permasalahan di atas. Konsekuensi dari peningkatan kecepatan pada jalur tersebut adalah keharusan meningkatan track quality index(TQI) yang terdiri dari empat parameter yaitu angkatan, listringan, lebar jalur dan pertinggian. TrackQuality Index(TQI) adalah standar nilai yang digunakan untuk mengevaluasi kualitas jalan rel. Nilai TQI dapat memantau degradasi trackdan operasi pemeliharaan, dapat meringkas dan menampilkan kondisi bagian besar track, dan berkorelasi dengan standar keamanan dan nilai kualitas berkendara (Hamid dan gross, 1981). TQI saat ini pada jalur eksisting untuk kecepatan maksimal 120 km/jam yang ditetapkan PT. KAI sebesar 20 untuk sepanjang lintas utara, namun sebagai objek penelitian hanya digunakan lintas Surabaya-Cepu. Dengan metode pendekatan berupa regresi linier sederhana yang melibatkan item TQI dan kecepatan, serta regresi linier berganda dengan item empat parameter penyusun TQI dan kecepatan.Sedangkan jumlah frekuensi pemecokan tahunan digunakan metode perhitungan PT. KAI. Dari hasil analisis model hubungandidapatkan rekomendasi nilai TQI untuk KA semicepat (160 km/jam) yaitu 7, Sedangkan jumlah frekuensi pemecokan tahunan adalah minimal 1 kali