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EFEKTIVITAS PERAN KOMITE SEKOLAH DALAM MENINGKATKAN KUALITAS PENDIDIKAN SEKOLAH DASAR DI KECAMATAN DORO KABUPATEN PEKALONGAN

Media Penelitian Pendidikan Vol 2, No 2 (2008)
Publisher : Media Penelitian Pendidikan

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Abstract

Penelitian ini mengkaji dua variabel, yakni variabel bebas peran komite sekolah (X) dan variabel terikat peningkatan kualitas pendidikan di SD (Y), sehingga akan diketahui keefektifan hubungan antara variabel bebas (X) dengan variabel terikat (Y). Populasi penelitian adalah ketua komite Sekolah Dasar sejumlah 32 SD Negeri dan Swasta yang terbesar di wilayah Kecamatan Doro. Karena jumlah populasi hanya 32, maka populasi dijadikan sampel penelitian. Teknik analisis data yang digunakan dengan regresi untuk instumen I yaitu untuk mengungkap 2 (dua) variabel yaitu variabel bebas (X) dan variabel terikat  (Y), hanya mencari kefektifannya. Untuk menganalisis strategi menggunakan binomial tes. Untuk menguji hipotesis dengan membandingkan r hitung dengan nilai r tabel untuk taraf kesalahan 5% dengan n=32 diperoleh 0,349 dan untuk 1% diperoleh 0,449. Harga r hitung lebih kecil dari r tabel baik untuk kesalahan 5% maupun 1% (0,219 < 0,39 < 0,449) dengan demikian Ha ditolak dan Ho diterima, disimpulkan peran komite sekolah tidak fektif dalam meningkatkan kualitas pendidikan Sekolah Dasar karena r hitung hanya mendapat 0,219 yang lebih kecil dari r tabel baik kesalahan 5% maupun 1%. Kecenderungan komite sekolah memilih strategi directing (pengarahan) 18 kasus, proporsi observasi 0,56. Kecenderungan memilih strategi brainstorming (curah pendapat) 14 kasus, proporsi observasi 0,44. Besarnya nilai proporsi kasus adalah 0,50 dengan asymply signifikan 0,596. Hasil penelitian ini direkomendasikan kepada: 1) Kepala Dinas Pendidikan Kabupaten Pekalongan melalui Kepala UPTD Pendidkan Kecamatan Doro agar dapat memberikan pengarahan kepada komite sekolah untuk berperan aktif dalam membantu meningkatkan kualitas pendidikan Sekolah Dasar di Kecamatan Doro Kabupaten Pekalongan, 2) Kepala Sekolah agar dapat bekerja sama dengan komite sekolah dalam upaya peningkatkan kualitas pendidikan Sekolah Dasar di Kecamatan Doro Kabupaten Pekalongan, 3) Komite Sekolah agar mengerti tugas dan tanggung jawabnya sehingga dapat berperan aktif dalam membantu meningkatkan kualitas pendidikan Sekolah Dasar di Kecamatan Doro Kabupaten Pekalongan.   Kata-kata kunci: peran komite sekolah, peningkatan, kualitas pendidikan

Meningkatkan Efektifitas Karburisasi Padat pada Baja Karbon Rendah dengan Optimasi Ukuran Serbuk Arang Tempurung Kelapa

Jurnal Teknik Mesin Vol 10, No 1 (2008): April 2008
Publisher : Institute of Research and Community Outreach - Petra Christian University

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Abstract

Pack carburizing is the simplest method of carburizing process that use charcoal powder as carbon element adder. The research target is to increase the effectiveness of charcoal powder as pack carburizing media. Coconut shell charcoal was made into powder then sifted with size of 150, 250, 279, 600, 850 and 2000 m. Specimens were Low Carbon Steel which contain 0,082 % C. The pack carburizing process was conducted for 4 hours at 850 0C. The hardening process was done by reheating at 850 0C with 5 minutes holding time and quenched into water of 28 0C to form Martensite structure that was observed by optic microscope and Micro Vickers Hardness Tester. The conclusion of the research are that 250 until 600 m powder size of coconut shell charcoal can use to pack carburizing media. With 4 hours for pack carburizing process, case depth of carbon diffusion on surface specimen is about 1200 m and surface hardness specimen increase 250% to base material Abstract in Bahasa Indonesia: Karburising padat merupakan metode karburisasi yang paling sederhana, yaitu meng¬gunakan serbuk arang sebagai penambah unsur Karbon. Tujuan penelitian adalah untuk meningkatkan efektivitas hasil proses karburising yang menggunakan serbuk arang tempurung kelapa pada Baja Carbon Rendah. Arang tempurung kelapa dibuat serbuk dan diayak dengan ukuran butir 150, 250, 279, 600, 850 dan 2000 μm. Benda uji yang digunakan adalah baja karbon rendah dengan kandungan 0,082% C. Proses karburising padat dilakukan pada suhu 850 0C selama 4 jam. Proses pengerasan dilakukan dengan memanaskan ulang benda uji pada suhu 850 0C, ditahan 5 menit, kemudian dicelup ke dalam air bersuhu 28 0C. Struktur Martensit yang terbentuk diamati dengan mikroskop dan diuji dengan Micro Vickers Hardness Tester. Dari penelitian ini disimpulkan bahwa serbuk tempurung kelapa dengan ukuran antara 250 hingga 600 µm efektif digunakan untuk proses karburising padat pada Baja Karbón Rendah. Dengan waktu tahan karburising selama 4 jam, maka akan terjadi difusi Karbón hingga kedalaman 1200 µm dan kekerasan permukaan baja dapat meningkat hingga 250% dari kekerasan semula. Kata kunci: Kaburising padat, difusi karbon, ukuran serbuk arang, Martensit.

PEMANFAATAN NATRIUM KARBONAT UNTUK MENINGKATKAN KUALITAS ARANG BAKAU PADA PROSES KARBURISING PADAT

Jurnal Penelitian Saintek Vol 17, No 1 (2012): APRIL 2012
Publisher : Jurnal Penelitian Saintek

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Abstract

Upaya peningkatan kualitas arang bakau untuk proses karburising padat telah dilakukan dengan penambahan natrium karbonat (Na2CO3). Arang bakau digilas menjadi serbuk dan disaring dengan ukuran mesh 30. Serbuk arang ini dicampur Na2CO3 dengan variasi 0, 15, 20, 25 dan 30 % berat. Hasil campuran ini digunakan untuk proses karburising padat pada benda uji baja karbon rendah dengan 98,34% Fe dan 0,156% C pada suhu 850oC selama 4 jam. Benda-benda uji hasil karburising ini dipanaskan kembali pada 850oC selama 5 menit, kemudian dicelupkan ke dalam air 28oC. Hasil penelitian menunjukkan bahwa penambahan 25% berat Na2CO3 menghasilkan case depth setebal yaitu 520 µm dan kekerasan permukaan maksimum 683 VHN. Perubahan struktur mikro dari ferrit-perlit ke martensit setelah proses pencelupan menunjukkan bahwa terjadi peningkatan unsur karbon pada permukaan benda uji baja ini hingga kedalaman 520 µm. Kata kunci: arang bakau, karburising padat, natrium karbonat

Biokomposit dari serat rami dan sekresi kutu lak termodifikasi dengan lateks terhidrasi dan tidak terhidrasi

Majalah Kulit, Karet, dan Plastik Vol 31, No 1 (2015): Majalah Kulit, Karet, dan Plastik
Publisher : Center for Leather, Rubber, and Plastic Ministry of Industry, Indonesia

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Abstract

Biocomposites are composite materials comprising one or more phases derived from a biological origin. Biocomposite with natural matrix developed more rapidly because they are more environmentally safer. The objective of research was to modify natural matrix from lac insect secretion with adding hydrated latex, to study effect of adding hydrated latex to the functional groups and the intrinsic viscosity of lac insect secretion, and to measure mechanical properties of biocomposite from modified lac insect secretion and ramie fiber. A sulfuric acid solution was used as catalyst in hydration of latex and then natural matrix of lac insect secretion was modified by adding hydrated latex. Biocomposite was prepared by mixing rami fiber and modified  lac insect secretion. It was then pressed with hydraulic press at 150 kgf/cm2 and 150oC for 15 minutes. Biocomposites were characterized using tensile tester according to ASTDM D 638-90 Type IV. The adding of catalyst caused the decreasing of intrinsic viscosity of latex. The adding of hydrated latex to natural matrix caused the increasing of intrinsic viscosity and functional group of matrix. The using 30% of catalyst and adding 10% of hydrated latex produced biocomposite with strength at break of 0.982 MPa, elongation at break of 1.189%, and Young modulus of 0.929 MPa.Keywords: biocomposite, hydration, latex, lac insect secretion, ramie fiber. ABSTRAK Biokomposit merupakan material komposit yang tersusun dari satu atau lebih komponennya berasal dari bahan alam. Biokomposit dari matriks alam berkembang lebih pesat karena lebih aman bagi lingkungan. Tujuan penelitian ini adalah untuk memodifikasi matriks dari sekresi kutu lak dengan penambahan lateks hasil hidrasi, mempelajari pengaruh penambahan lateks hasil hidrasi terhadap gugus fungsi dan viskositas intrinsik matriks, dan untuk mengukur sifat mekanik biokomposit dari matriks hasil modifikasi dengan serat rami. Lateks dihidrasi dengan variasi katalis asam sulfat 10, 20, dan 30% (m/m). Matriks alam dari sekresi kutu lak dimodifikasi dengan penambahan lateks hasil hidrasi sebanyak 5, 10, dan 15% (m/m). Biokomposit dibuat melalui pencampuran sekresi kutu lak hasil modifikasi dengan serat rami dan dipress pada tekanan 150 kgf/cm2 dan suhu 150oC selama 15 menit. Biokomposit dikarakterisasi menggunakan tensile tester sesuai dengan ASTDM D 638-90 tipe IV. Penambahan katalis menurunkan viskositas intrinsik lateks terhidrasi. Penambahan lateks terhidrasi meningkatkan viskositas intrinsik dan gugus fungsi matriks. Biokomposit dari matriks alam sekresi kutu lak termodifikasi lateks terhidrasi dengan penggunaan katalis 30% dan penambahan lateks terhidrasi sebesar 10% mempunyai kuat tarik sebesar 0,982 MPa, elongasi saat putus sebesar 1,189%, dan modulus Young sebesar 0,929 MPa.Kata kunci: biokomposit, hidrasi, lateks, sekresi kutu lak, serat rami.

New biocomposite material from ramie fibre and natural matrix of flee secretion on albasia tree as expansion effort of teaching material

JOURNAL OF EDUCATION Vol 1, No 1 (2008): Year 1, Number 1, November 2008
Publisher : JOURNAL OF EDUCATION

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Abstract

Abstract:  A biocomposite is a composite which consists of natural fiber as reinforcement and  matrix  as  binder  agents.  Biocomposite  materials  are interesting phenomena   because  they  are  environmentally friendly,   are renewable resources, and can increase the economic level of the neighbouring people.  The objective of the present study is to look into the feasibility  of biocomposite material from secretion of albasia flea  as a binder agent and ramie fiber  as reinforcement. Secretion of albasia flea  was collected from Ciamisforest, WestJava, Indonesia with lumps type and then was reacted with methylated spiritus to liquefaction. Heating of the dilution offlea secretion at180°C in 15 minutes decreased the viscosity to become gel. The gels were layered on the surface of ramie fiber  woven roving with the hand layout method. Molding of the biocomposite was done at 180-200°C in 10 minutes after 2-4 layers of ramiefiber were soaked with gel, pressing with pressure 40MPa,  and  cooling  at room temperature in 4  hours. Density  and  tensile strengths of the biocomposite were evaluated with ASTM D638-90 standard and compared withpublicized biocomposites to know itsfeasibility. The tensile strength of the biocomposite from  60% of ramie fiber  woven roving andsecretion of albasiaflea was 80 MPa with a density of 1.17g/cm. This result showed that the biocomposite had a relatively higher tensile strength and lower density than an epoxy or polyester  matrix. The biocomposite of the matrix of albasia flea  secretion can become a novel material, have high feasibility  based on availability of renewable resources, give simplicity of matrix processing, need no high technology on molding biocomposite, and have higher tensile strength relative to lower density. An implication of the results of the study can be in the development of new teaching material in the engineering  material  subject  of  study  in  the Faculty  of Engineering  of YogyakartaState University.Keywords: biocomposite, ramiefiber, secretion of .albasiaflea, natural matrix, tensile strength, density, binder agent, reinforcement

PENINGKATAN RASIO PEMAMPATAN TEBAL GERAM DAN PENGURANGAN KEAUSAN PAHAT DENGAN MEMODIFIKASI PAHAT BERMATA POTONG DVA PADA MESIN BUBUT

Jurnal Penelitian Saintek Vol 10, No 1 (2005): April 2005
Publisher : Jurnal Penelitian Saintek

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Abstract

This  research   is   aimed   to   determine   the   differences   of   chipcompression ratio and tool wear between a modified double cuttingtool and a standard cutting tool.The workpiece is made of VCN 150 with a dimension of e 1,75 inchand 200 mm long. Because the diameter of the blank is constant, the spindle rotation is set to 265 RPM  Both cutters use the same coolant and have the same  cutting angle.  The properties  to be varied are depth  of  cuts  and feed   Depth  of  cuts  of standard  cutting  tool  is formulated by the blank diameter substituted by the final diameter and than divided by two. The same formulation  goes for  depth of cuts of modified cutting tool. Tool wears and chip compression ratio values chosen  is  the  biggest  value  on  each  cutting  edge.  Steps  of  this research one: Record the tool wear and chip compression ratio for each feed,  which one 0,043; 0,066; 0,0875; and 0,/75  mmlrev while using depth of cuts of 0,5; I; 1,5 and 2 mm. Each treatment is done 5 times or each cutting stroke  and the average  is  taken  as a result. Comparing tool wear and chip compression ratio resulted from  the utilization of modified cutting tool and standard tool.It can be concluded from  the result  of this research  that (I)  using modified cutting tool, there is an improvement of chip compression ratio  equal  to  6,74%   compared  to  the  standard  cutter  (2)  using modified cutting tool there is a reduction tool wear equals to 14,53% compared the standard cutting /001.Keywords: chip thickness compression ratio, /001 wear,feed, and deep.                  of cut.

Brebes Buroq: The Art Expression of Coastal Javanese Moslem Society

KOMUNITAS: INTERNATIONAL JOURNAL OF INDONESIAN SOCIETY AND CULTURE Vol 8, No 1 (2016): Komunitas, March 2016
Publisher : Universitas Negeri Semarang

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Abstract

The art of Buraq is a procession of puppet which has beautiful female face with winged-horse body and dance to the music of Genjring and tambourine. This traditional art is one of the dominant arts that becomes one cultural identity of the people in Brebes District, located in the west of the northern coast of Java island, Central Java Province. This study aims to study the aesthetic form, function and symbolic values of Buroq, as well as the system of relationship patterns among actors, Buroq puppets, and the audience. The result of the research shows that the rise of Buroq art stems from the Isra-Miraj trip of Prophet Muhammad by using the vehicle named Buroq. It is narrated that Buraq is like a winged-horse with a beautiful woman face who can move with lightning speed as a vehicle in the Isra-Miraj journey of the Prophet Muhammad. This story is the primary source of inspiration for local artists to express aesthetic-symbolic in accordance with the imagination they possess in the form of acculturation that combines elements of Javanese, Chinese, and Islamic cultural symbols. As Islamic-based traditional arts of community, Buroq with all the uniqueness of its physical form not only has functions and values in the grandeur of Islam which awakens and strengthens the cultural awareness among residents to act and behave in accordance with the teaching of Islam in coastal Javanese Islamic culture but also has the functionality and entertainment value for the multicultural community.

Meningkatkan Efektivitas Arang Bakau Pada Proses Karburising Padat Baja Karbon Rendah Menggunakan Barium Karbonat

Jurnal Semesta Teknika Vol 12, No 2 (2009): NOVEMBER 2009
Publisher : Jurnal Semesta Teknika

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Abstract

The effect of BaCO3 on bakau charcoal effectiveness as a carburizer for pack carburizing process was investigated. Bakau charcoal being produced from bakau trees were sifted on 30 mesh sieve. BaCO3 was then added into the bakau charcoal sieves with composition of 0, 15, 20, 25, and 30 wt %. The pack carburizing was carried out at 850 0C for 2 hours. Low-carbon steel containing 0.156 %C was used as specimen. After being carburized, all specimens were reheated at 850 0C, hold it for 5 minutes, and subsequently quenched into water at 28 oC. The result shows that BaCO3 improves bakau charcoal effectiveness as a solid media in pack carburizing proces. By adding of 20, 25 dan 30 wt % of BaCO3, it produced the case depth of 190 mm, 250 mm dan 325 mm, respectively. Martensite structure that arises on steel surface after being quenched indicates the increase of the amount of carbon atoms. 

Morphological Analysis of Anopheles vagus Donitz, 1902 (Diptera : Culicidae ) in fresh water and brackish water habitats = Variasi Morfologi Anopheles vagus Donitz, 1902 (Diptera : Culicidae) dari Habitat Air Tawar dan Air Payau

Vektora : Jurnal Vektor dan Reservoir Penyakit Vol 6, No 2 Okt (2014)
Publisher : Balai Besar Penelitian dan Pengembangan Vektor dan Reservoir Penyakit (B2P2VRP) Salatiga

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Abstract

ENGLISHAbstractAnopheles subpictus had habitat variation and showed genetic difference. So, the variation of habitat of An. vagus may support the hypothesa that An. vagus had genetic and morphology variation, same as An. subpictus.The aimed of this research was analyze morphology and chaetotaxy difference between An. vagus in fresh water and brackish water. The subject of the study was An. vagus collected from Kesongo Village, Tuntang Subdistrict, Semarang (fresh water) and Jatimalang Village, Purwodadi Subdistrict, Purworejo (brackish water). Anopheles vagus were collected and individually reared. One sample in every batch was used to make larvae skin, pupae skin and adult specimen of An. vagus. The result showed that there were intra and inter population variation between An. vagus in fresh water and brackish water. The variations were on the size and number of hair branches and filaments. The conclution of this research were the morphology and chaetotaxy of female An. vagus in fresh water and brackish water showed no different. Intra and interpopulation An. vagus in fresh water and brackish water were caused by the difference of geography location (allopatric speciation).INDONESIANVariasi habitat terjadi pada An. subpictus, variasi habitat yang berbeda menunjukkan variasi genetik yang berbeda. Oleh karena itu variasi habitat An. vagus diduga akan bepengaruh terhadap variasi genetik dan morfologi. Tujuan penelitian adalah menganalisis perbedaan morfologi dan kaetotaksi Anopheles vagus habitat air tawar dan air payau. Subyek penelitian adalah An. vagus habitat air tawar di Desa Kesongo, Kecamatan Tuntang, Kabupaten Semarang dan An. vagus habitat air payau di Desa Jatimalang, Kecamatan Purwodadi, Kabupaten Purworejo. Anopheles vagus yang diperoleh, di rearing secara individual. Tiap indukan diambil satu sampel keturunannya dan dibuat preparat skin larva, skin pupa dan nyamuk dewasa betina. Hasil menunjukkan bahwa Anopheles vagus betina habitat air tawar dan air payau menunjukkan variasi intra dan interpopulasi. Variasi terdapat pada ukuran dan jumlah cabang rambut atau filament. Kesimpulan penelitian adalah An. vagus betina habitat air tawar dan air payau tidak menunjukkan perbedaan. Variasi intra dan interpopulasi An. vagus betina terjadi karena perbedaan letak geografi (allopatric speciation). 

Brebes Buroq: The Art Expression of Coastal Javanese Moslem Society

KOMUNITAS: INTERNATIONAL JOURNAL OF INDONESIAN SOCIETY AND CULTURE Vol 8, No 1 (2016): Komunitas, March 2016
Publisher : Universitas Negeri Semarang

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Abstract

The art of Buraq is a procession of puppet which has beautiful female face with winged-horse body and dance to the music of Genjring and tambourine. This traditional art is one of the dominant arts that becomes one cultural identity of the people in Brebes District, located in the west of the northern coast of Java island, Central Java Province. This study aims to study the aesthetic form, function and symbolic values of Buroq, as well as the system of relationship patterns among actors, Buroq puppets, and the audience. The result of the research shows that the rise of Buroq art stems from the Isra’-Mi’raj ‘ trip of Prophet Muhammad by using the vehicle named Buroq. It is narrated that Buraq is like a winged-horse with a beautiful woman face who can move with lightning speed as a vehicle in the Isra’-Mi’raj journey of the Prophet Muhammad. This story is the primary source of inspiration for local artists to express aesthetic-symbolic in accordance with the imagination they possess in the form of acculturation that combines elements of Javanese, Chinese, and Islamic cultural symbols. As Islamic-based traditional arts of community, Buroq with all the uniqueness of its physical form not only has functions and values in the grandeur of Islam which awakens and strengthens the cultural awareness among residents to act and behave in accordance with the teaching of Islam in coastal Javanese Islamic culture but also has the functionality and entertainment value for the multicultural community.