PROFIL PEMAHAMAN KONSEP MATEMATIKA DITINJAU DARI GAYA KOGNITIF FIELD INDEPENDENT (FI) DAN FIELD DEPENDENT (FD)

abstrak: Penelitian ini bertujuan untuk mendeskripsikan pemahaman konsep matematika siswa kelas XI SMA Negeri 2 Dampelas dalam menyelesaikan soal pada subpokok bahasan parabola ditinjau dari gaya kognitif Field Independent (FI) dan Field Dependent (FD). Jenis penelitian ini adalah penelitian kualitatif. Subjek dalam penelitian ini terdiri dari satu siswa yang bergaya kognitif FI dan satu siswa yang bergaya kognitif FD. Hasil dari penelitian ini yaitu saat menyajikan masalah, subjek FI dan FD menuliskan hal-hal yang diketahui dan ditanyakan. Selanjutnya dalam mengklasifikasi unsur-unsur parabola, subjek FI mengelompokkan unsur-unsur parabola menurut bentuk parabolanya yaitu parabola horizontal terbuka ke kanan. Kemudian dalam memberi contoh dan non-contoh pada setiap unsur-unsur parabola, subjek FI memberikan contoh dan non-contoh dari setiap unsur-unsur parabola yang diberikan. Kemudian menyajikan masalah persamaan parabola dalam representasi matematis, subjek FI dan subjek FD menyajikan persamaan parabola kedalam bentuk persamaan umum parabola. Kemudian menggunakan, memanfaatkan dan memilih prosedur tertentu dalam menentukan persamaan parabola, subjek FI menggunakan dan memilih persamaan umum parabola horizontal dan subjek FD menggunakan persamaan umum parabola walaupun subjek tidak mengetahui jenis persamaan umum parabola yang digunakan. Kemudian subjek FI menjelaskan kembali prosedur yang digunakan serta memberikan alasannya dengan menggunakan bahasanya sendiri dan subjek FD menjelaskan kembali prosedur yang digunakan walaupun dalam proses penyelesaiannya siswa belum memahami dengan baik langkah-langkah yang harus digunakan. Kata Kunci: Profil; Pemahaman konsep matematika; Parabola; abstract: This study aims to describe the understanding of mathematical concepts of class XI students of SMA 2 Dampelas in solving problems on the subject of the parabolic discussion reviewed from cognitive style of the Independent Field (FI) and Field Dependent (FD). This type of research is qualitative research. The subjects in this study consisted of one student who was in the cognitive style of FI and one student in the cognitive style of FD. The results of this study are when presenting a problem, FI and FD subject write things that are known and asked. Furthermore, in classifying parabolic elements, FI subjects classify parabolic elements according to their parabolic forms, namely horizontal parabola open to the right. Then in giving examples and non-examples of each parabolic element, the FI subject gives examples and non-examples of each parabolic element given. Then presenting the problem of parabolic equations in mathematical representations, the subject FI and subject FD present the parabolic equation in the form of a general parabolic equation. Then using, utilizing and selecting a particular procedure in determining the parabolic equation, FI subject uses and selects the general horizontal parabolic equation and the FD subject uses the general parabolic equation even though the subject does not know the type of general parabolic equation used. Then the FI subject explains the procedure used again and gives the reason using its own language and the FD subject explains the procedure used even though in the process of completion students do not understand the steps that must be used properly. Keywords: Profile; Understanding of mathematical concepts; Parabolic

Cable Elements for Numerical Analysis of Highline Cable System of Alongside Replenishment

Various of cable elements are used in the numerical analysis of cable structures. According to the mechanical characteristics of highline cable system of alongside replenishment at sea, two cable elements are investigated: catenary element, which is the exact solution, and parabolic element, which is the approximate solution but simpler to calculate. The equilibrium equations of each cable element are introduced, and the expressions of tangent stiffness matrix are derived. The tangent stiffness matrix of catenary element is calculated through Newton interactive method.

Divergence type of some subgroups of finitely generated Fuchsian groups

Let Г be a finitely generated discrete subgroup of the isometries of the hyperbolic plane H2 with at least one parabolic element. We prove that, if Г1 is a subgroup of Г with Г/Г1 abelian, the ‘critical exponent’ of Г1 is the same as that of Г. We give necessary and sufficient conditions-in terms of the rank of Г/Г1, the critical exponent of Г, and the image of parabolic elements of Г in Г/Г1 - for the Poincaré series of Г1 to diverge at the critical exponent.