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Alkhafi Maas Siregar
Jurusan Fisika FMIPA Universitas Negeri Medan
Control & Systems Engineering Earth & Planetary Sciences Electrical & Electronics Engineering Materials Science & Nanotechnology Mechanical Engineering Physics

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Interpretasi Penentuan Struktur Bawah Permukaan Berdasarkan Data Geofisik Tahanan Jenis Di Desa Mardinding Julu Kecamatan Sibiru-Biru Anna Dinna; Alkhafi Maas Siregar
EINSTEIN (e-Journal) Vol 4, No 1 (2016): EINSTEIN
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (403.836 KB) | DOI: 10.24114/einstein.v4i1.7872

Abstract

Penelitian ini bertujuan untuk mendapatkan bentuk interpretasi penentuan struktur bawah permukaan daerah potensi panas bumi di Desa Mardinding Julu Kecamatan Sibiru-biru berdasarkan data geofisik tahanan jenis. Interpretasi dilakukan menggunakan metode inversi dalam bahasa pemrograman MATLAB, menggunakan data nilai arus, faktor geometri dan beda potensial. Dimulai dari mengkomfirmasikan persoalan fisika ke dalam bentuk numerik sehingga memenuhi persamaan matriks yang ditentukan. Selanjutnya proses manipulasi persamaan matriks sehingga perkalian antar matriks menghasilkan matriks bujursangkar, tahap akhir yaitu dilanjutkan dengan prosedur inversi yang dilakukan satu-per-satu dengan menggunakan matriks kernel. Hasil dari interpretasi struktur bawah permukaan berupa gambar kontur yang divisualisasikan dari nilai resistivitas yang menunjukkan struktur bawah permukaan memiliki nilai resistivitas minimun dan maksimal sebesar 1,54 – 1552 Ωm terdiri dari air tanah, tanah lempung, tanah lanau, tanah lanau pasiran dan batu gamping. Sedangkan lapisan yang mengandung fluida panas bumi memiliki nilai resistivitas antara 1,54 – 8,34 Ωm pada kedalaman mulai dari permukaan sampai 28,7 meter dan lapisan yang paling berpotensi dari ketiga lintasan adalah lintasan kedua dengan resistivitas terendah. Penyebaran fluida panas dari ketiga lintasan berturut-turut diperkirakan adalah ± 55,83%, ±43,81% dan ± 25,44%.Kata kunci: Metode Inversi, MATLAB, Resistivitas
THE EFFECT OF PROBLEMBASED LEARNING MODELTOWARD STUDENT LEARNING OUTCOME INDYNAMICELECTRICITY TOPIC AT CLASS XIN SMA NEGERI 1PERBAUNGANACADEMIC YEAR 2014/2015 Yenni Manurung; Alkhafi Maas Siregar
INPAFI (Inovasi Pembelajaran Fisika) Vol 4, No 4 (2016): INPAFI
Publisher : UNIVERSITAS NEGERI MEDAN

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (31.38 KB) | DOI: 10.24114/inpafi.v4i4.5658

Abstract

ABSTRACT The objective of this research to know the significant difference of student learning outcome using Problem Based Learning Model in dynamic electricity topic at class X SMA Negeri 1 Perbaungan Academic Year 2014/2015.The type of research was quasi-experiment with the population is all of students at class X in odd semester consist of six classes.Sample of this research was obtained by cluster random sampling technique.The research instrument has  seven questions in essay form,the instrument tested validated.Research result obtained the average value of posttest in experiment class was 80.63 and 75.53for control class was higher than control class.It can be concluded that there was significant difference towards student learning outcomes using Problem based Learning Model.   Keywords : Problem Based Learning Model,Dynamic Electricity
THE EFFECT OF GUIDED DISCOVERY LEARNING MODEL ON STUDENT’S ACHIEVEMENT AT CHARACTERISTICS OF WAVE TOPIC IN SMA N 1 MEDAN CLASS XI ACADEMIC YEAR 2014/2015 Yohana Glorya Tobing; Alkhafi Maas Siregar
INPAFI (Inovasi Pembelajaran Fisika) Vol 4, No 2 (2016): INPAFI
Publisher : UNIVERSITAS NEGERI MEDAN

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (34.948 KB) | DOI: 10.24114/inpafi.v4i2.5523

Abstract

ABSTRACT The aim of this research was to find the effect of guided discovery learning model on student’s achievement at characteristics of wave topic in SMA N 1 Medan class XI academic year 2014/2015. The research method was quasi-experiment. The populations were all 2nd grade students odd semester consist of 13 classes in SMA N 1 Medan. The samples of this research conduct two classes and consist of 37 students from experiment class and control class defined by cluster random sampling. The results that were obtained: post-test mean value of the experiment class was 75.94 and 75.02 for control class. Standard deviation for two classes was 14.94 and 12.48. Normality of the test result from the both samples was normal and homogeneous. So, there was the significant effect of using guided discovery learning model. It can conclude that studying with guided discovery learning model was higher than direct instructional learning model.   Key word: guided discovery learning, student’s learning achievement, learning model, physics
Co-Authors Anna Dinna Yenni Manurung Yohana Glorya Tobing