Abstrak. Penelitian ini bertujuan untuk meningkatan motivasi dan hasil belajar peserta didik IX A SMP Negeri Unggulan Sindang Kabupaten Indramayu pada materi Pangkat Tak Sebenarnya dan Bentuk Akar dengan menggunakan media kartu domino matematika. Penelitian ini merupakan penelitian tindakan kelas (PTK) yang dilaksanakan dua siklus dan setiap siklus berlangsung empat kali pertemuan sesuai dengan rencana pelaksanaan pembelajaran. Pelaksanaan penelitian dilakukan pada proses pembelajaran semester genap yaitu bulan Januari 2014. Subjek penelitian ini adalah siswa kelas IX A SMP Negeri Unggulan Sindang Indramayu tahun pelajaran 2013/2014 berjumlah 29 orang yang terdiri atas 16 siswa perempuan dan 13 siswa laki-laki. Teknik analisis data yang digunakan adalah teknik analisis data kualitatif dan yaitu dengan cara reduksi data, penyajian data dan penarikan kesimpulan serta verifikasi data dengan teknik triangulasi. Hasil penelitian menunjukkan bahwa peggunaan media kartu domino matematika dapat meningkatkan motivasi dan hasil belajar matematika peserta didik. Nilai rata-rata tes hasil belajar pra tindakan adalah 61,03 dengan ketuntasan 13%, sementara pada siklus I hasil belajar siswa mengalami peningkatan sebesar 19,66 dimana rata-rata belajar menjadi 80,69 dengan ketuntasan belajar 79,31%. Begitu juga setelah pelaksanaan pada siklus II terjadi peningkatan sebesar 7,83 di mana ratarata hasil belajar menjadi 88,52 dengan ketuntasan belajar 86,21%.

The suitability of bamboo’s basic characteristics is very important for more specific purposes, such as composite raw materials. Anatomical, physical, mechanical, and chemical characteristics are some of bamboo’s fundamental characteristics. This study analyses the basic properties, such as physical, mechanical, and chemical properties of bamboo from the Forest Area with Special Purpose (FASP) Pondok Buluh Sumatera Island, Indonesia (I); analyses the relationship between the properties of each type of bamboo (II); and chooses the type of bamboo with the best properties that have the potential to be applied to composite materials, such as laminated bamboo (III). This study used materials consisting of six species of bamboo from the FASP Pondok Buluh. The manufacture of physical and mechanical test samples refers to the ISO 22157 standard, 2004, while the chemical properties test refers to the TAPPI 1999 standard. The chemical, physical, and mechanical properties of bamboo vary widely among species. The lowest holocellulose and α-cellulose content were found in the Kuning Bamboo (B. vulgaris var. vittata). The content of holocellulose and α-cellulose causes the lowest density in Kuning Bamboo (B. vulgaris var. vittata). The Dasar Bamboo (Bambusa vulgaris) has the highest levels of lignin. The substances have an impact on moisture content, T/R ratio, and shear strength. The Dasar Bamboo (Bambusa vulgaris) has the lowest moisture content, the highest T/R ratio, and the highest shear strength. However, Betung Bamboo (Dendrocalamus asper) has the highest density in this study. The compressive strength of the Betung Bamboo (Dendrocalamus asper) has the highest value. Therefore, Betung bamboo and Dasar Bamboo in this study were potentially utilized for composite materials, such as laminated bamboo.

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Bearing strength largely affects the performance of wood connections. This study, determines the bearing strengths of six Indonesian tropical hardwoods with different specific gravities (ranging from 0.43 to 0.84) by half-hole testing. The results for three bolt diameters were compared to the bearing strengths in the Indonesian National Standard (SNI) and the National Design Specification (NDS) for Wood Construction. Next, the bolt-bearing strengths were related to the specific gravities and mechanical properties of the woods. With increasing specific gravity, the bearing strength increased from 26 to 70 MPa. The experimentally obtained bearing strengths of light and heavy red meranti, mersawa, kapur and bangkirai woods were 3-15% and 11-23% lower than the SNI and NDS values, respectively. In contrast, the experimental result for merbau was 23 and 11% higher than the SNI and NDS values, respectively. The bearing strength most closely approached the compression strength parallel to the grain.

AbstrakPenelitian pemanfaatan sludge sebagai bahan baku pembuatan papan serat berkerapatan sedang atau medium density fibreboard (MDF) berguna untuk menciptakan nilai tambah dari sludge. Tujuan dari penelitian ini adalah mengevaluasi sifat fisis, mekanik, dan ketahanan MDF dari sludge terasetilasi dengan 4 macam konsentrasi asetat anhidrida (0%, 3%, 5% dan 7%) dengan 3 kali ulangan. Pembuatan MDF dilakukan dengan proses kering. Setelah bahan baku dicampur perekat, dilakukan pengempaan dengan menggunakan kempa panas dengan suhu AbstractMedium Density Fibreboard Made of Acetylated Sludge from Paper Mill. Research of using sludge as raw material for making medium density fibreboard (MDF) was useful to create additional value of sludge. The objective of the research was to evaluate physical properties, mechanical properties, and durability of MDF from acetylated sludge in 4 levels of acetate anhydride (0%, 3%, 5%, and 7%) with 3 replicates. The MDF was made using dry process. After materials were mixed with adhesives, they were pressed using hotpress under 170 o C temperature and 45 Pa pressure for 25 minutes. The size of the MDF sample was 25 cm x 20 cm x 1 cm with 0.8 g/cm 3 density. The physical properties (density, moisture content, water absorption, thickness swelling) and mechanical properties (modulus of elasticity, modulus of rupture, internal bond, screw holding power) was tested based on JIS A 5905-2003 standard. The durability was evaluated using SNI 01-7207-2006. All physical properties of MDF fulfill JIS A 5905-2003. Acetate anhydride decreased the moisture content value of MDF. On the other hand, all mechanical properties did not fulfill the standard. That was caused by calcium carbonate in sludge that blocked the adhesion between sludge fibres. The durability of MDF tested here was classified Class I which is very resistant to termites.