Farah Dina - Academia.edu (original) (raw)

Papers by Farah Dina

The Qualitative Report

Teachers’ competences should be shaped from a very early stage of their training (Mâţă, Cmeciu, &... more Teachers’ competences should be shaped from a very early stage of their training (Mâţă, Cmeciu, & Ghiaţău, 2013). For that reason, pre-service teachers are required to get involved in teaching internships and gain professional experience from training programs and workshops. These experiences are assets for these pre-service teachers when they resume teaching positions upon graduation. The present narrative study, therefore, aims to investigate the benefits of international teaching internship, known as South-East Asian Teacher (henceforth SEA-Teacher Program) on Indonesian pre-service English teachers’ identity and competence development. There were four male and four female participants of SEA-Teacher program participated in the study. The data for this study was generated through in-depth semi-structured phone and email interviews. The study reveals that this program has developed personal competences of the pre-service teachers, in which they improve self-confidence, coping mech...

Jurnal Ilmiah Teknik Elektro Komputer dan Informatika

This paper presents an experimental study to support the concept of generating energy by a contin... more This paper presents an experimental study to support the concept of generating energy by a continuous flow of water using piezoelectric sensors. This study is aimed to determine the effect of external force direction of continuous water flow, i.e., vertical and horizontal, on the output of the piezoelectric sensors. The piezoelectric type of ABT-441-RC is used and arranged in parallel. IC MAX471 as an amplifier and Arduino Uno R3 to read the flow rate, voltage, and current were employed. Flow rates with variations of 0.00011 up to 0.00030 m 3 /s are set to study the voltage and current of the output. The numbers of piezoelectric sensors used are 4, 6, 8, and 20. As a result, it is found that the pressure in the vertical direction differs up to 68% from the pressure in the horizontal one. The voltage and current in the vertical direction, compared to that of the horizontal direction, differ as much as 85% at a low flow rate and decrease down to 63% at a high flow rate for voltage and 86% to 34% at a low to high flow rate for current. In conclusion, the current generation by the present arrangement is within the micro-ampere range, and the voltage is in a volt range, respectively.

JURNAL SELULOSA, 2021

Indonesia merupakan penghasil limbah plastik terbesar kedua setelah Cina, sehingga telah menjadi ... more Indonesia merupakan penghasil limbah plastik terbesar kedua setelah Cina, sehingga telah menjadi isu lingkungan. Salah satu kemasan plastik yang banyak digunakan adalah kemasan untuk pembibitan terbuat dari plastik atau dikenal sebagai polybag. Guna membantu mengurangi penggunaan polybag, telah dilakukan percobaan skala laboratorium pembuatan paper bag dari pulp tandan kosong sawit (TKS) sebagai pengganti polybag. Penelitian ini bertujuan untuk mendapatkan formula pembuatan paper bag yang dapat memenuhi persyaratan penggunaan akhirnya. Kegiatan dimulai dari penggilingan pulp TKS, dilanjutkan dengan pembuatan lembaran dengan variasi gramatur 90 g/m2 dan 125 g/m2 pada rentang pH 7-8. Dua jenis bahan kimia penguat basah yang digunakan yakni polietilen imin (PEI) dan poliamin epiklorohidrin (PAE), ditambahkan dengan variasi dosis 1,0 – 2,0 % terhadap berat kering serat. Karakteristik lembaran dievaluasi melalui uji ketahanan tarik, daya regang, daya serap energi (tensile energy absorpti...

E3S Web of Conferences, 2021

Solar thermal water heating systems have been developed to replace conventional heating. Therefor... more Solar thermal water heating systems have been developed to replace conventional heating. Therefore, the design of a parabolic cylinder collector-type solar heating unit with a coil-shaped heater (absorber) has been carried out. The cylindrical collector is made of an aluminum plate covered with a reflective sticker and the base is insulated, having a diameter, height, length, and position of the focal point 150, 60, 200, and 22.4 cm, respectively. The coil water heater of 3/8-inch diameter copper pipe having a diameter, pitch, and length of 20, 3, and 200 cm, respectively. The concentration ratio between collector area and heating pipe area (absorber) is 3.6. The results of heating trials conducted from 10:00 to 16:00 WIT, in Duplo to 100 liters of water circulated through the heating pipe at a speed of 0.017 kg/sec, indicate that heating is affected by fluctuations in radiation intensity. Thermal efficiency is inversely proportional to heating time. the lower the time when the diff...

Pati modifikasi diperoleh dengan mereaksikan pati tapioka dan enzim lokal α -amilase selama 20 me... more Pati modifikasi diperoleh dengan mereaksikan pati tapioka dan enzim lokal α -amilase selama 20 menit pada variasi temperatur 65⁰ C – 80⁰ C. Variasi penambahan enzim 0,04 % - 0,1% terhadap berat kering tapioka. Selanjutnya pati enzim yang diperoleh pada kondisi optimum diaplikasikan sebagai aditif pada proses pembuatan kertas secara asam dan alkali dengan pembanding pati tapioka dan pati kationik. Hasil percobaan modifikasi pati diperoleh pati enzim yang optimum pada kondisi enzim 0,04% dan temperatur 70⁰ C. Hasil aplikasi menunjukkan bahwa penambahan 1% pati modifikasi pada proses alkali mampu meningkatkan ketahanan sobek melebihi ke dua pembanding tersebut. Sementara itu nilai retensi awal (FPR) dan ketahanan tariknya lebih tinggi dari pati tapioka tetapi lebih rendah dari pati kationik. Sifat-sifat lainnya seperti laju drainase dan penetrasi cairan (Cobb 60 ) lebih baik pada proses alkali, sedangkan sifat optiknya lebih baik pada proses asam. Kata kunci : a ditif kertas, enzim, pa...

Generally, Hot water is needed to drink, to take a bath and to steam a boiler by humankind for da... more Generally, Hot water is needed to drink, to take a bath and to steam a boiler by humankind for daily needs and it is created by flaming fossil energy. Flamming fossil fuel is not only generating carbon dioxide to the atmosphere but also one of the reason to make the higher temperature of the earth which spark climate changes. Solar power is one of the best solution to solve this problem for our safety future. Solar power is a clean energy, continuous, and un limited. Thermal solar collector flat plate 300 is used to trapped the solar energy and the power is transferred to the pipes which is filled by R-134a refrigerant so the effect is occurring raised temperature as R134a refrigerant. Due to “rho” differences, hot and cold, Refrigerant - 134a is circulating naturally to create the hot water. This thesis aims to know the pressure of one closed-glass collector efficiency in 90 Psi, 100 Psi and 110 Psi. So from this study we know that the best collector effiency pressure is in 110 Psi...

Drying of red chili (Capsicum annuum L.) using heat pump dryer has been done to obtain dryingcond... more Drying of red chili (Capsicum annuum L.) using heat pump dryer has been done to obtain dryingconditions at relatively low temperature and humidity so that the damage of the vitamin which it iscontains can be reduced. The design, manufacture and testing of heat pump dryer for dryingagricultural products has been done. The drying chamber is made of aluminum plate sized500mmx500mmx500mm, insulated with rockwool wrapped in aluminum foil. Heat pump used wassplit air conditioner with a cooling load of 9000 Btu/hr. A test result of design and manufacturingis done by drying red chili to look at the performance of the heat pump dryer. Studies conducteddryer performance includes the calculations of coefficient of performance (COP), TotalPerformance (TP),Specific Energy Consumption (SEC), Specific Moisture Extraction Rate (SMER)of heat pumps and also to know the characteristics of drying red chili. The results were obtained:average air temperatures enter the drying chamber is 54,17C and avera...

Penelitian ini bertujuan untuk menguji pengaruh aktivitas pengelolaan lingkungan hidup terhadap k... more Penelitian ini bertujuan untuk menguji pengaruh aktivitas pengelolaan lingkungan hidup terhadap kinerja keuangan perusahaan pertambangan yang terdaftar di Bursa Efek Indonesia (BEI) berdasarkan Pernyataan Standar Akuntansi Keuangan nomor 33 (PSAK 33). Terdapat tiga variabel independen pada penelitian ini yaitu pengungkapan biaya pengupasan lapisan tanah, pengelolaan lingkungan hidup akibat eksplorasi dan evaluasi, dan pengelolaan lingkungan hidup akibat produksi, sedangkan yang menjadi variabel dependen adalah kinerja keuangan (Return on Investment). Objek dalam penelitian ini adalah perusahahaan pertambangan yang terdaftar di Bursa Efek Indonesia (BEI) periode 2011- 2013. Jenis penelitian yang digunakan merupakan penelitian kuantitatif. Data yang dianalisis menggunakan Statistical Package for Social Science (SPSS) dengan menggunakan analisis regresi berganda. Hasil pengujian hipotesis menunjukkan bahwa pengungkapan biaya pengupasan lapisan tanah dan penyisihan pengelolaan lingkunga...

Penelitian uji coba pemasak tenaga surya dengan tipe kolektor parabola yang digunakan untuk memas... more Penelitian uji coba pemasak tenaga surya dengan tipe kolektor parabola yang digunakan untuk memasak beras dengan rasio 1:1 telah dilakukan. Kolektor surya dengan diameter 150cm dan tinggi 60 cm dirancang dari alumunium foil dan absorber berupa alumunium yang berdiameter 20 cm dan tinggi 14 cm. Pengujian dilakukan dari jam 10.00 s.d 16.00 WIB dengan interval waktu 10 menit, variasi pembebanan yang di uji adalah 200 gr, 400 gr dan 600 gr. Penelitian ini bertujuan untuk mengetahui pengaruh perbandingan laju pemasakan, kapasitas pemasakan dan intensitas radiasi matahari. Intensitas radiasi matahari dan efisiensi terbaik diperoleh pada pembebanan 200 gr (waktu pemasakan 60 menit, I = 564,43 W/m 2 , (h) = 28,59 % ), 400 gr (waktu pemasakan 80 menit, I = 519,89 W/m 2 , (h) = 66,35 % ), 600 gr (waktu pemasakan 120 menit, I = 535,94 W/m 2 , (h) = 90,69 %). Secara keseluruhan disimpulkan bahwa laju pemasakan berbanding lurus terhadap intensitas radiasi matahari namun berbanding terbalik t...

Penelitian tentang pengering integrasi energi surya menggunakan kolektor tipe plat datar bersirip... more Penelitian tentang pengering integrasi energi surya menggunakan kolektor tipe plat datar bersirip dan termokimia untuk mengeringkan biji kakao-fermentasi telah dilakukan. Pemasangan sirip pada kolektor menambah luas permukaan absorber dan meningkatkan energi surya yang diserap. Pengeringan dilanjutkan malam hari menggunakan absorben dan dapat mempersingkat waktu pengeringan. Pengeringan biji kakao-fermentasi dengan kadar air awal rata-rata 62,6% dilakukan pada 18-19 Juni 2014 hingga mencapai kadar air 7,6%. Energi surya dilakukan selama siang hari pukul 08:30-16:00 WIB, dilanjutkan dengan energi termokimia menggunakan absorben berupa garam CaCl 2 pada malam hari pukul 16:00-08:30 WIB keesokan harinya. Pengeringan dihentikan pada saat dicapai berat konstan. Evaluasi terhadap kondisi dan potensi radiasi, efisiensi termal kolektor surya, efektifitas absorben , dan model kinetika pengeringan. Hasil menunjukkan bahwa selama proses pengeringan berlangsung, kondisi cuaca siang hari dicatat...

Beberapa pertimbangan dalam analisis dan pemilihan strategi jangka panJang, berkaitan dengan stra... more Beberapa pertimbangan dalam analisis dan pemilihan strategi jangka panJang, berkaitan dengan strategi ditingkat perusahaan. Untuk memahami peran strategi tersebut, para penentu strategi dapat memilih satu atau beberapa diantara 14 strategi umum dari Pearce & Robinson, dan mereka juga menggunakan rancangan portfolio untuk menghubungkan selurub bisnis-bisnis dalam perusahaan mereka, salah satunya dengan Boston Consulting Group. Portfolio dengan pendekatan BCG menggunakan matrik pertumbuhan pangsa pasar (The Growth-Share Matrix) atau disebut juga dengan matrik BCG. Matrik BeG membagi sebuah daerah dengan garis vertikal dan horisontal menjadi 4 kuadran, yaitu: question mark, star, cash cow dan dog. Garis vertikal menunjukkan tingkat pertumbuhan pasar sedangkan garis horisontal menunjukkan pangsa pasar relatif.

Research has conducted on pyrolysis process of plastic reject waste using fly ash catalyst from c... more Research has conducted on pyrolysis process of plastic reject waste using fly ash catalyst from coal. The research was conducted at the USU Laboratory in Medan and the Medan Industrial Baristand by using variations in the number of catalysts, namely 0, 10, 20 and 40% of the reject plastic weight. When the pyrolysis process is carried out at varying temperatures of 300; 350 and 400 o C. An indicator of the potential of Bio-Oil from reject plastic can be analyzed by looking at the viscosity, density and heating value of the yield of bio-oil obtained. The results of the pyrolysis process obtained an increase in the number of fly ash catalysts in the pyrolysis process while increasing the amount of bio-oil fuel produced. The use of an excess amount of fly ash catalyst can produce more difficult condensable gases which cause an increase in the number of fly ash catalysts which will further reduce the amount of fuel oil. The highest amount of liquid fuel is obtained in pyrolysis using a 4...

Telah dilakukan penelitian perancangan alat kolom adsorpsi untuk pemurnian biogas dari limbah c... more Telah dilakukan penelitian perancangan alat kolom adsorpsi untuk pemurnian biogas dari limbah cair pabrik kelapa sawit, melalui proses perhitungan kolom adsorpsi. Proses perancangan perhitungan dengan menggunakan silinder tegak dan stainless steel untuk menyerap gas H2S dalam biogas. Proses perancangan menggunakan metode studi literatur dan berdasarkan sifat-sifat dari biogas yang akan di murnikan. Proses selanjutnya dilakukan proses pembuatan desain alat kolom adsorpsi. Pembuatan alat dilakukan menggunakan material stainless steel sesuai dengan perhitungan desain. Menggunakan beberapa rumus perhitungan desain diperoleh spesifikasi kolom adsorpsi yaitu tinggi adsorben 5,6 meter, jari jari kolom 0,039 meter, tebal dinding kolom 3,01 mm dan gas yang akan di murnikan adalah gas H2S dalam biogas dengan kapasitas 100 liter per batc

Di Indonesia hingga saat ini pengeringan padi adalah dengan cara penjemuran langsung dibawah sina... more Di Indonesia hingga saat ini pengeringan padi adalah dengan cara penjemuran langsung dibawah sinar matahari selama 3 – 4 hari. Dalam penelitian ini telah dilakukan pengeringan padi menggunakan pengering surya tipe kolektor silinder parabola. Ruang pengering berbentuk tabung silinder dengan diameter 20 cm dan panjang 200 cm yang ditempatkan pada posisi titik fokus kolektor. Didalamnya dilengkapi dengan screw conveyor yang digerakkan oleh motor pada kecepatan yang divariasikan 23, 28 dan 35 rpm. Tujuan dari penelitian ini adalah untuk melihat pengaruh intensitas radiasi matahari terhadap profil temperatur yang dihasilkan, pengaruh kecepatan putaran screw terhadap waktu dan konsumsi daya selama pengeringan serta menetapkan model kinetika pengeriingan pada kondisi kecepatan screw yang optimum.Pengujian dilakukan secara triplikat dan terbagi dalam 4 batch per hari dan setiap batch mengandung 5 kg padi dengan kadar air awal 28%. Selama pengeringan berlangsung intensitas radiasi, temperatu...

Jurnal Dinamika Penelitian Industri, 2018

Penelitian tentang Rancang Bangun dan Ujicoba Pengering Surya Tipe Kolektor Tabung Vakum untuk me... more Penelitian tentang Rancang Bangun dan Ujicoba Pengering Surya Tipe Kolektor Tabung Vakum untuk mengeringkan kopi telah dilakukan. Penelitian ini dilakukan dengan melalui tahap perumusan, perancangan, perangkaian dan uji coba alat menggunakan kopi sebagai bahan untuk dikeringkan. Hasil uji coba diperoleh suhu udara pengering yang lebih tinggi maka waktu pengeringan dapat lebih singkat dan laju pengeringan lebih besar. Hasil rancang bangun pengering surya ini selanjutnya diuji coba untuk mengeringkan kopi dari kadar air 52,80% hingga kadar air 12,30%, dengan sistem konveksi paksa yang memvariasikan kecepatan udara 2-6 m/sec. Selama pelaksanaan pengeringan kondisi cuaca rata-rata berada pada rentang 143-855 Watt/m2, temperatur lingkungan 28-35 C. Temperatur udara didalam kolektor 85-192 C dan temperatur didalam ruang pengering adalah 35-78 C. Hasil uji coba untuk pengeringan biji kopi menunjukkan bahwa kecepatan udara berbanding lurus dengan laju pengeringan, efisiensi kolektor dan berbanding terbalik dengan waktu pengeringan dan konsumsi energi spesifik (KES).

Indian Journal of Science and Technology, 2019

Objectives: One of clean technology applications in daily human life activity is the use of solar... more Objectives: One of clean technology applications in daily human life activity is the use of solar thermal energy, such as for rice cooking. As a country where most of its territory is on the equator, this environmentally friendly solar cooker can be reversed due to the high intensity of radiation received throughout the day. Therefore, design and trial run ofsolar cooker with parabolic collector has been done. Methods and Analysis: The collector produced has a diameter of 150 cm, depth 60 cm and the length of the focal point of 23.44 cm. The parabolic equation resulted is X 2 = 93.76 Y or Y = 0.01067 X 2. The collector is made of aluminum plates coated with aluminum foil on the surface and isolated with Rockwool at the bottom. While the cooking pot (absorber) is made of aluminum with a diameter of 20 cm and a height of 14 cm. Findings: From this dimension a concentration ratio of 56.25 is obtained. The trial results on cooking 400 grams of rice (ratio of rice: water = 1: 1) showed that cooking time and thermal efficiency were strongly influenced by solar irradiation. Applications: The optimum condition was achieved at an average solar irradiation of 520 W/m 2 ,which obtained 90 minutes of cooking time with 56% thermal efficiency.

Jurnal Riset Teknologi Industri, 2016

This study aims to determine the performance of a continuous and intermittent sun drying of ferme... more This study aims to determine the performance of a continuous and intermittent sun drying of fermented-cocoa bean by using thin-layer drying method. Continuous drying using a solar dryer finned-flat plate collector type which is operated in two modes drying time, daytime and night time. During the day, the cocoa beans are dried in the drying chamber using hot air generated by the solar collectors. In the nighttime, desiccant (CaCl2) was added to the drying chamber that had been isolated. Open sun drying as intermittent drying of cocoa beans is done only on daytime. The drying process is terminated when equilibrium moisture content has been achieved. The results showed that the continuous drying rate higher than the intermittent drying. Dried-cocoa beans produced from continuous drying showed a lower moisture content (7.34% vs 7.50%), a better physical appearance, but the higher the degree of acidity (pH = 5.93 vs. 6.13). Total fat content and free fatty acids slightly lower than the ...

AIP Conference Proceedings, 2017

Research on the effect of openings solar collector and solar irradiance to thermal efficiency has... more Research on the effect of openings solar collector and solar irradiance to thermal efficiency has been done. Solar collector by flat plate-finned type consists of 3 ply insulator namely wood, Styrofoam and Rockwool with thickness respectively are 10 mm, 25 mm and 50 mm. Absorber plate made of aluminum sheet with thickness of 0.30 mm, painted by black-doff. Installation of 19 units fins (length x height x thickness: 1000x20x10 mm) on the collector will increase surface area of absorber so it can receive much more solar energy. The solar collector cover is made of glass (thickness of 5 mm). During the research, the solar irradiance and temperature of collector are measured and recorded every five minutes. Temperature measurement performed on the surface of the absorber plate, inside of collector, surface cover and the outer side insulator (plywood). This data is used to calculate the heat loss due to conduction, convection and radiation on the collector. Openings of collectors vary as follows: 100%, 75%, 15% and 0% (total enclosed). The data collecting was conducted from 09.00 am to 17.00 pm and triplicates. The collector thermal efficiency calculated based on the ratio of the amount of heat received to the solar irradiance absorbed. The results show that each of openings solar collector has different solar irradiance (because it was done on a different day) which is in units of W/m 2 : 390 (100% open), 376 (75% open), 429 (15% open), and 359 (totally enclosed). The highest thermal efficiency is in openings variation of 15% opened. These results indicate that the efficiency of the collector is influenced by the solar irradiance received by the collector and the temperature on the collector plate. The highest thermal efficiency is in variation of openings 15%. These indicate that the efficiency of the collector was influenced by solar irradiance received by the collector and openings of the collector plate.

Jurnal Litbang Industri, 2014

Pada penelitian ini, perilaku pengeringan menggunakan pengering kakao tenaga surya telah dilakuka... more Pada penelitian ini, perilaku pengeringan menggunakan pengering kakao tenaga surya telah dilakukan. Kakao diambil dari perkebunan di sekitar daerah Sumatera Utara-Indonesia. Energi surya digunakan sebagai sumber energi pengeringan yang hemat dan bersih. Kakao merupakan komoditi andalan di Indonesia hanya saja mutu yang saat ini dihasilkan masih terbilang rendah. Penelitian ini bertujuan untuk mendapatkan persamaan pengeringan dengan pemodelan matematika untuk menghasilkan mutu kakao yang baik. Tahap preparasi dimulai dari proses fermentasi kakao. Dari beberapa kali pengujian kakao, diambil hasil salah satu pengujian dimana hasil fermentasi kakao yang telah dicuci kemudian dikeringkan dari kadar air 55,83% menjadi 7,01% yang berlangsung selama tiga hari secara intermitten. Penelitian