598 research outputs found

    Optimasi Konfigurasi Mainjet Dan Slowjet Karburator Motor Bensin Satu Silinder 97 Cc

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    This paper describes a study that compared performance and emission from a 97 cc small single cylinder gasoline engine using five differences carburetor jet configuration. The study is based on the engine test bed results. The test results have shown that the bigger main jet produce slightly higher torque and power than the smaller one, but the fuel consumption also higher. The emission test results have shown a higher hydrocarbon (HC) and carbon monoxide (CO) for bigger main jet configuration. However Oxide of Nitrogen (NOx) emission from bigger main jet configuration was generally lower. The smallest jet configuration produced to lean fuel air mixture and caused engine over heat. The data obtained in this study indicate that the best configuration for the engine tested is 72/38 jet configuration

    Emisi Gas Buang Kendaraan Bermotor Berbahan Bakar Gas Cair (Lgv) Dan Pertamax Pada Kondisi Uji Awal Dingin Dan Panas

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    Liquid Gas Vehicle (LGV) is one of an alternative hydrocarbon fuel, which is the dominant composition are propane and butane, and now is already available in the market. With low sulfur content and high octane number, theoritically vehicle emissions using LGV are better than gasoline. But it is need a good mixture ratio of air to LGV (AFR) in the gas mixer before enter to the engine. This paper describes a study that compared emission test results from gasoline engine using LGV with standard mixer and Pertamax market fuel. The study was based on the vehicle chassis dynamometer test results according to the UN-ECE R83-04 test cycle standard on both cold and hot starts. The test results have shown that on urban cycle CO and HC emissions of Pertamax fuel was better than LGV on both cold and hot starts. Whereis on extra urban cycle CO emission of LGV fuel was better than Pertamax. NOx emission of LGV fuel was very low and practically undetected for all test condition. Utilisation of LGV fuel reduce CO2 emission in order of 15% for urban drive cycle for both cold and hot start, and in order of 9,2% for cold start and 10.5% for hot start for mixed cycle

    Examination of Acid-Fast Bacilli in Sputum Using Modified Light Microscope with Homemade Light Emitting Diode Additional Attachment

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    Typical clinical symptoms and chest X-ray is a marker of Tuberculosis (TB) sufferers. However, the diagnosis of TB in adults should be supported by microscopic examination. Currently, Bacilli microscopic examination of acid-fast bacilli (AFB) in sputum by Ziehl-Neelsen (ZN) coloring is the most widely used. However, for reasons of convenience, especially for laboratories with a considerable amount of smear samples, and due to higher sensitivity compared with ZN staining, the World Health Organization (WHO) has recommended the use of auramine-O-staining (fluorochrome  staining), which is visualized by light emitting diode (LED) fluorescence microscopy. The aim of this study was to evaluate the performance of modified light microscope with homemade LED additional attachment for examination of AFB in sputum using auramine-O-staining method. We compared the sensitivity and specificity of 2 kinds of AFB in sputum methods: ZN and fluorochrome, using culture on Lowenstein-Jensen media as the gold standard. The results showed auramine-O-staining gives more proportion of positive findings (81%) compared to the ZN method (70%). These results demonstrated that the sensitivity of auramine-O-staining was higher than ZN, however it gives more potential false positive results than ZN. The sensitivity of auramine-O-staining in detecting AFB in sputum was 100% while the specificity was 88%

    Stomatal Conductance and Chlorophyll Characteristics and Their Relationship with Yield of Some Cocoa Clones Under Tectona Grandis, Leucaena SP., and Cassia Surattensis.

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    An optimum physiological condition will support high yield and quality of cocoa production. The research was aimed to study the effects of stomatal conductance and chlorophyll content related to cocoa production under three shade regimes.This research was conducted in Kaliwining Experimental Station, elevation of 45 m above sea level with D climate type based on Schmidt & Fergusson. Cocoa trees which were planted in 1994 at a spacing of 3 X 3 m were used in the study planted by using split plot design. The shade tree species were teak (Tectona grandis), krete (Cassiasurattensis), and lamtoro (Leucaena sp.) as the main plots, and cocoa clones of Sulawesi 01,Sulawesi 02, KKM 22 and KW 165 as sub plots. This study showed that there was interaction between cocoa clone and shade species for stomatal conductance where stomatal diffusive resistance of KKM 22 was the best under Leucaena sp.and Cassiasurattensis with the values of 1.38 and 1.34 s.cm -1, respectively. The highest chlorophyll content, stomatal index and transpiration values was under Leucaena sp. shade. There was positive correlation between chlorophyll content and transpiration with pod yield of cocoa. The highest yield and the lowest bean count wereobtainedon Sulawesi 01 clone under Leucaenasp. shade

    Pengaruh Tekanan dan Suhu terhadap Faktor Kompressibilitas Gas Alam (Studi Kasus Gas Alam Rumah Tangga)

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    Penggunaan rumus perhitungan faktor kompressibilitas gas alam secara manual dan hanya menggunakan satu parameter saja yaitu tekanan (Pa) oleh pihak penjual gas untuk pelanggan rumah tangga mengakibatkan adanya ketidaknyamanan dan pertanyaan dari masyarakat sebagai pelanggan gas terhadap keakuratan, keabsahan dan kehandalan rumus tersebut dikarenakan seharusnya faktor kompressibilitas gas alam dipengaruhi juga oleh suhu (Ta). Penelitian ini dilakukan di badan metrologi gas Jakarta yang mempunyai standar Internasional yaitu EN 12405 dan AGA NX19. Data yang didapat kemudian diolah dan dianalisa menggunakan program SPSS versi 16. Berdasarkan hasil pengolahan data dan analisa tersebut didapat bahwa suhu (Ta) juga mempunyai pengaruh terhadap faktor kompressibilitas (Zb/Zm) akan tetapi karena nilainya sangat kecil sekali maka pengaruh ini dapat diabaikan

    Pendidikan Karakter Melalui Pembelajaran Matematika Menggunakan Catatan Khusus Berkarakter

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    Setiap tindakan mendidik selalu memiliki demensi pembentukan karakter dalam diri siswa (Albertus D. K., 2015a). Sebagai guru matematika masih belum dapat mengendalikan secara baik terutama tentang perilaku siswa tanpa berkaitan dengan mata pelajaran dengan buku catatan khusus seperti halnya jurnal mengajar. Buku catatan khusus siswa dapat untuk mencatat siswa yang telah mempresentasikan soal matematika di depan kelas dan menandatangani buku catatan khusus tersebut sebagai catatan positif sebagai perhatian guru, sering kali untuk mencatat hal negatif siswa yang memerlukan tindak lanjut. Catatan khusus siswa menjadi motivasi untuk berlomba mempresentasikan ditandai dengan tanda tangan siswa. Menjadi keharusan pembelajaran matematika dapat menumbuhkan dan menguatkan karakter kreatif, gigih, cinta damai, toleran, dan, rasa ingin tahu (Sumardyono, 2004). Terinspirasi Art-ong Jumsai Na Ayudhya dalam Bukunya berjudul Integration of Human Values in Sciences and Mathematics perlunya memaparkan beberapa ide nilai-nilai karakter dalam pembelajaran matematika yang harus terus menerus menuangkan nilai-nilai kemanusiaan kepada anak. Karakter yang dapat ditumbuh-kuatkan dengan cara pandang fallibilist antara lain: kreatif, toleran, peduli lingkungan, demokratif, gigih, religius, cermat, argumentatif, dan masih banyak lagi. Filsafat fallibilist juga sesuai dengan berbagai deskripsi matematika yang telah dibahas di bagian sebelumnya. Karakteristik matematika yang beragam berpotensi untuk menumbuhkan dan menguatkan karakter baik langsung maupun tidak langsung. Dari dua golongan besar cara pandang matematika: absolutis dan fallibilis, maka cara pandang fallibilis dianggap lebih berpotensi untuk menumbuhkan karakter melalui pembelajaran matematika

    PENGEMBANGAN MEDIA BELAJAR POP UP BOOK PADA MATERIKOLOID DI KELAS XI IPA SMA NEGERI 4 BANDA ACEH

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    Penelitian ini bertujuan untuk mengembangkanmediapop up bookpadamaterikoloidsebagai sumber belajar mandiri peserta didik kelas XI IPA SMAN 4 Banda Aceh dan mendeskripsikan aktivitas belajar siswa/i menggunakan media pop up book.Model pengembangan yang digunakan adalah model ADDIE (Analysis, Design, Development, Implementation, dan Evaluation).Metode pengukuran aktivitas siswa/i menggunakan lembar observasi yang mencakup 6 aspek penilaian.Pengembangan produk ditinjau darisegi mediadanmateri. Data yang diperoleh adalah data kuantitatif yang diubah menjadi data kualitatif. Data kuantitatif ditabulasi dan dianalisis menggunakan kriteria kategori penilaian ideal untuk menentukan kelayakanmedia pop up book.Hasil penelitian ini adalah produk yang berupa pop up bookmateri koloid dengan persentasekelayakan media darivalidator 1 dan validator 2masing-masing sebesar67,5% dan 78,5% tergolong kategori layak serta aktivitasbelajar peserta didik menggunakan media pop up bookpertemuan pertama sebesar 76,21% dan pertemuan kedua sebesar 86,25% dan tergolong dalam kategori baik. Hal ini menunjukan bahwa media pop up bookpada materi koloid dapat digunakan sebagai media pembelajaran di Sekolah.Media pop up bookjuga dapat digunakan pada materi kimia yang lain
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