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Kajian Hasil Pembuatan Tiga Macam Ukuran Lubang Berbentuk Persegi Panjang Pada Tubuh Tungku Sekam Darmasetiawan, H.; Irzaman, Irzaman; Demijati, Demijati; Siswadi, Siswadi
BERKALA FISIKA Vol 13, No 2 (2010): Berkala Fisika, Edisi Khusus
Publisher : BERKALA FISIKA

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Abstract

Husk furnace is used for cooking fuel chaff with the aid of air flow in the furnace. One measurement of the husk furnace efficiency can be studied by varying the size of the primary air holes on the body of the furnace. In this study, a hole measuring 22 cm X 24 cm obtained by the rate of fuel consumption of 6.03 kg / hour of heat energy needed to boil water as much as 6 liters is 2575.00 kcal / h and 14.32% efficiency furnace. While in the hole measuring 22 cm X 8 cm and 22 cm X 16 cm, respectively 12.92% and 12.87% efficiency furnace, not significantly different.   Keywords: chaff, husk furnace, ukuruan primary air hole, furnace efficiency
PERHITUNGAN POLARISASI SPONTAN DAN MOMEN QUADRUPOL POTENSIAL LISTRIK BAHAN PIZT (PbInxZryTi1-x-yO3-x/2) Muhammad Hikam; Edy Sarwono; Irzaman .
Makara Journal of Science Vol 8, No 3 (2004): Desember
Publisher : Directorate of Research and Community Engagement, Universitas Indonesia

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Abstract

The Calculation Spontaneous Polarization and Quadrupole Moment of Electric Potential PIZT (PbInxZryTi1-x-yO3-x/2). PZT (PbZr1-xTixO3) is a perovskite crystal that can be used for IR sensor. Small amount of dopant can drastically change the specific characteristic of ferroelectric ceramic such as spontaneous polarization, dielectric constant, electromechanical and also electro-optic properties. The addition of In3+ ion (called as hard doping) has been applied in this research. Thin film of PIZT (PbInxZryTi1-x-yO3-x/2) has been deposited on Si(100) substrate with Chemical Solution Deposition (CSD) method. The concentration of solution is 0,5 M and the angular speed applied of spin coating is 3000 rpm. The PIZT sample has been analyzed with x-ray diffraction method. Rietveld analyses using GSAS-EXPGUI software resulted lattice parameter of crystal and phase compositions of PIZT samples. The values of all sample PIZT spontaneous polarization (Ps) have been calculated lower than PZT. The optimally Ps was reached at 0,5% to 1% In2O3 doping. Quadrupole moment of electric potential (θQ(r)) at point P (0,0,2a) reached optimum at 6% In2O3 doping and they also showed that PIZT thin film have θQ(r) higher value than their bulk form for In2O3 doping >1%.Keywords: PZT, PIZT, XRD, Rietveld analyses, spontaneous polarization, quadrupole moment of electric potential
Optimasi Tungku Sekam Skala Industri Kecil Dengan Sistem Boiler Nawafi, F; Puspita, D; Desna, Desna; Irzaman, Irzaman
BERKALA FISIKA Vol 13, No 3 (2010): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

Rice husk furnace  is a technology based on local wisdom to anticipate threats crisis energy. At first investigated husk stoves for cooking only in the scale of the household, but today rice husk furnace developed for industrial scale because of the importance of commercial aspects of a very promising from this rice husk furnace. In rice husk furnace also developed an industrial scale boiler system, boiler systems where it can enlarge its efficiency, in the midst of a boiler chimney pots have used, because basically rice husk furnace process is influenced by air flow. Husk furnace efficiency greatly affect the number of furnace ash which is required in the cooking process.   Keywords: rice husk, rice husk furnaces, air flow, efficiency, boilers.
Penerapan Film Tipis Ba0.25Sr0.75TiO3 (BST) Yang Didadah Ferium Oksida Sebagai Sensor Suhu Berbantukan Mikrokontroler Ardian, A.; Nady, L.; Erviansyah, R.; Syafutra, H.; Irzaman, Irzaman; Siswadi, Siswadi
BERKALA FISIKA Vol 13, No 2 (2010): Berkala Fisika, Edisi Khusus
Publisher : BERKALA FISIKA

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Abstract

Ferroelectric material originating from Barium Strontium Titanate (BST), is expected to have high energy because it has a dielectric constant and high charge storage capacity [6]. Materials produced by the process of ferium dopan, it is hoped will be a temperature sensor. If, materials BST and BFST (Barium Ferium Strontium Titanate) subjected to the temperature (material change that temperature), and the resulting voltage, then this material can be applied as a temperature sensor using a microcontroller. Microcontroller that used is ATMega 8535 with internal ADC. Voltage was generated, will be reinforced with a voltage amplifier (OpAmp) and will be processed into digital data at the ATMega8535 internal ADC (Analog Digital Converter).Incoming digital data will be processed and displayed in the view Microcontroller-based desktop applications Delphi 7. The material to be tested is material BST, BFST 5%, and BFST 15%.   Keyword: BST, Temperature sensor, ATMEGA 8535, ADC, Delphi 7
Studi Konduktivitas Listrik Film Tipis Ba0.25Sr0.75TiO3 Yang Didadah Ferium Oksida (BFST) Menggunakan Metode Chemical Solution Deposition Irzaman, Irzaman; Erviansyah, R; Syafutra, H; Maddu, A; Siswadi, Siswadi
BERKALA FISIKA Vol 13, No 1 (2010): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

Has done growth Ba0,25Sr0, 75TiO3 (BST) thin film and BST are pure Ferium Oxide Fe2O3 dopant (BFST) with dopant variations 5%, 10% and 15% above the substrate Si (100) type-p using Chemical Solution Deposition Method (CSD) with the spin coating technique at a speed of around 3000 rpm for 30 seconds. BST thin films made with 1 M concentration and annealing at a temperature of 850°C for Si Substrate. Thin film on silicon substrate type-p thickness characterization performed using the volumetric method and the characterization of electrical conductivity by using LCR meter. From the characterization results showed the thickness increases with the addition of ferium oxide dopant given. Electrical conductivity value of BST and BFST thin films are in the range semiconductor materials and electrical conductivity values obtained increased when the higher intensity light is used whereas resistance value could decrease if the light intensity is increased. The addition of ferium oxide dopant will increases electrical conductivity value of BST and BFST thin films.   Keywords : BFST, thin film, CSD, spin coating, electrical conductivity
DAMPAK KEGIATAN PELEDAKAN PERTAMBANGAN ANDESIT TERHADAP LINGKUNGAN PEMUKIMAN DI GUNUNG SUDAMANIK KECAMATAN CIGUDEG KABUPATEN BOGOR Simbolon, Aljon Albertus Manotar; Yani, Muhamad; Irzaman, Irzaman
Jurnal Manusia dan Lingkungan (Journal of People and Environment) Vol 22, No 2 (2015)
Publisher : Pusat Studi Lingkungan Hidup Universitas Gadjah Mada

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Abstract

Aspek lingkungan hidup kemungkinan terganggu akibat kegiatan eksploitasi sumber daya alam. Mineral dan batuan sebagai salah satu sumber daya alam pada umumnya tersebar di daerah terpencil yang masih memerlukan pengembangan. Pada sisi ini, kehadiran perusahaan pertambangan sangat penting peranannya bagi kemajuan dan pembangunan serta meretas keterisolasian suatu daerah. Wilayah sekitar Gunung Sudamanik, Kecamatan Cigudeg, Kabupaten Bogor tumbuh dan berkembang karena pertambangan andesit. Gunung Sudamanik telah dan masih dieksploitasi lima perusahaan tambang andesit yang memiliki Izin Usaha Pertambangan (IUP) dengan luas total Wilayah Izin Usaha Pertambangan (WIUP) seluas 113 hektar. Pada tahun 2012, total produksi batuan kelima perusahaan adalah 3.984.785 ton atau rata-rata 332.065,4 ton per bulan. Produksi batuan tersebut dihasilkan dari peledakan yang dapat mencapai lima kali peledakan atau lebih setiap hari. Getaran dan bunyi ledakan yang disebabkan peledakan ini kemungkinan berdampak terhadap lingkungan hidup, terutama pada konstruksi rumah dan kenyamanan masyarakat yang bermukim di sekitar kaki Gunung Sudamanik. Pemukiman penduduk yang paling dekat lokasi peledakan andesit berada pada tiga kampung/dusun yaitu Kampung Kadaung, Lebakwangi Lapangan dan Lebakwangi Girang. Ketiga kampung tersebut secara administratif berada dalam Desa Rengasjajar. Rumah warga pada pemukiman yang paling dekat ke lokasi peledakan batuan andesit berjarak sekitar 337 – 616 meter. Hasil penelitian menunjukkan bahwa pemakaian 90,5 kg bahan peledak delay yang sama pada jarak 148 m mengakibatkan tingkat getaran tanah maksimum 7,71 mm/s yang telah melewati baku mutu kelas 3 SNI 7571 : 2010. Dan pemakaian bahan peledak mulai dari 77,4 kg sampai 1310,4 kg setiap peledakan tidak menimbulkan dampak kebisingan pada pemukiman warga
KARAKTERISASI OPTIK DAN STRUKTUR KRISTAL LiTaO3 PADA SUBSTRAT SILIKON [Si(111)] TIPE-n/n+ Sani, Yulia; Ukhtiningsih, Ira; Herawan, Bambang; Maddu, Akhiruddin; Irzaman, -
Jurnal Spektra Vol 16, No 2 (2015): Spektra: Jurnal Fisika dan Aplikasinya
Publisher : Jurnal Spektra

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AbstrakTelah berhasil dibuat film LiTaO3 pada substrat silikon [Si(111)] tipe-n/n+ dengan variasi suhu annealing selama 8 jam pada suhu  600 oC, dan 625 oC. Metode yang digunakan yaitu Chemical Solution Deposition (CSD) dengan spin coating berkecepatan putar 3000 rpm selama 30 detik dalam kelarutan 1 M. Analisis energi band gap menggunakan metode Tauc Plot diperoleh hasil nilai  2.58 dan 2.57 eV. Hasil analisis XRD untuk film LiTaO3 pada suhu annealing 600 0C menunjukkan bahwa struktur kristalnya membentuk hexagonal dengan parameter kisi a=b=5.199Å dan c=13.890Å . Hasil uji optiknya dapat mengabsorbsi spektrum Inframerah dekat dengan transisi tidak langsung, dan termasuk material semikonduktor.Kata kunci : Energi gap, LiTaO3, sifat optik, silikon tipe n/n+, XRD AbstractLiTaO3 films had been successfully deposited on the substrate of n/n+-type Silicon [Si(111)] wich temperature variant for 8 hours at temperature of 600 oC, and 625 oC. The method can be used Chemical Solution Deposition (CSD) and spin coating with rotational speed 3000 rpm for 30 seconds and 1 M solubility. Analysis of the band gap energy using Tauc Plot method produce results of 2.58 eV and 2.57 eV. The result of XRD Crystal structure analysis showed that LiTaO3 film annealed at 600 oC show a hexagonal structure  with lattice parameters of a = b = 5.199Å and c = 13.890Å. The result of optical characterization has shown that LiTaO3 can absorb near infrared spectrum through indirect transition and indicates that LiTaO3 films is semiconductor  materials.Keywords: band gap energy, LiTaO3, optical property, n/n+-type Silicon [Si(111)], XRD.
ANALISIS EFISIENSI TERMAL KOMPOR BERBAHAN BAKAR SEKAM DAN LIMBAH BAGLOG PADA STERILISASI JAMUR TIRAM Firdaus, Fitrah Hadi; Fitriana, Ana; Nurmaniah, Irlian; Risanti, Maya; Setiawan, Ardian Arif; Irzaman, -
Jurnal Spektra Vol 16, No 1 (2015): Spektra: Jurnal Fisika dan Aplikasinya
Publisher : Jurnal Spektra

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AbstrakTelah berhasil dilakukan sterilisasi jamur tiram menggunakan kompor sederhana berbahan bakar sekam dan limbah baglog dengan diberi selongsong (pipa konveksi) di dalam alat sterilisasinya. Sterilisasi bertujuan membunuh bakteri dan jamur lain yang tidak diinginkan pada baglog. Hasil sterilisasi menunjukan bahwa kompor berbahan bakar sekam memiliki nilai efisiensi energi termal yang tinggi.  Efisiensi bahan bakar sekam sebesar 11.87% dan efisiensi bahan bakar limbah baglog sebesar  4.31 %, dengan waktu pengukusan selama 6 jam.Kata kunci : baglog,  efisiensi energi, sekam padi, selongsong.   AbstractSterilization of oyster mushroom with convection pipe has been successfully done. Rice huck and waste baglog are fuel of stove as sterilization. The purpose of sterilization is to kill bacteria and other fungi which are undesirable in baglog. Sterilization result showed that stove with rice huck had high thermal efficiency. The highest thermal efficiency is 11.87% for sterilization by using rice husk and efficiency of baglog waste fuel is 4.31 % with 6 hour of steam.Keywords: baglog waste, convection pipe, efficiency, rice husk.
UJI STRUKTUR KRISTAL DAN SIFAT LISTRIK FILM Ba0.55Sr0.45TiO3 DENGAN VARIASI PENDADAHAN La2O3 Ramlan, Tantan Taopik; Irzaman, -; Alatas, Husin
Jurnal Spektra Vol 16, No 2 (2015): Spektra: Jurnal Fisika dan Aplikasinya
Publisher : Jurnal Spektra

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Abstract

AbstrakTelah dibuat film Ba0.55Sr0.45TiO3 di atas substrat Si (111) tipe-n dengan metode CSD dan spin coating berkecepatan putar 3000 rpm selama 30 detik dalam kelarutan sebesar 1 M. Film BST didadah La2O3 dengan variasi 0%, 1%, 3%, 5% serta di annealing pada suhu 850 oC selama 15 jam dengan laju kenaikan 1.67 oC/menit. Karakterisasi struktur film berupa pengujian XRD. Hasil yang diperoleh memperlihatkan intensitas difraksi tertinggi dimiliki oleh film dengan variasi pendadahan 5% sedangkan intensitas difraksi terendah dimiliki oleh film dengan variasi pendadahan 0%. Pendadahan meningkatkan intensitas difraksi sinar-X pada film. Analisis struktur kristal BST menggunakan metode XRD menunjukkan bahwa struktur kristal BST berbentuk tetragonal. Hasil uji sifat listrik menunjukkan karakteristik film BST termasuk material semikonduktor.Kata kunci: BST, sifat listrik, struktur kristal, annealing, La2O3 AbstractBa0.55Sr0.45TiO3 (BST) thin film, was doped by lantanum oxide (La2O3), has been made with doping variations  0%, 1%, 3%, and 5% above substrat Si (111) n-type by using chemical solution deposition methods by spin coating technique at 3000 rpm for 30 seconds in 1 M concentration and 850 oC annealing temperature at 15 hour with rate 1.7 oC/minute. Structure characterization was using XRD. Result of XRD showed 5% doping has highest diffraction intensity and 0% is the lowest. Diffraction intensity increased by doping on film. Crystal structure analysis showed BST and BFST are tetragonal. Electrical properties showed that BST and BSLT thin film are semiconductor material.Key words : BST, electrical properties, crystal structure, annealing, La2O3
Simulation on the Use of LOSAT Data for Rice Field Mapping Trisasongko, Bambang H.; Panuju, Dyah R.; Tjahjono, Boedi; Barus, Baba; Wijayanto, Hari; Raimadoya, Mahmud A.; Irzaman, Irzaman
Makara Journal of Technology Vol 14, No 2 (2010)
Publisher : Directorate of Research and Community Services, Universitas Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (556.915 KB) | DOI: 10.7454/mst.v14i2.187

Abstract

Since the launch of LAPAN-TUBSAT satellite in 2007, Indonesia has been developing mission on earth observation missions for various applications. The next generation mission, called LAPAN-ORARI Satellite (LOSAT), is currently under development and expected to be launched in 2011. In order to facilitate the applications, a thorough assessment of the sensor should be made. This paper presents an examination of simulated LOSAT data for rice monitoring and mapping purposes coupled with QUEST statistical tree. We found that three-band simulated LOSAT data were suitable for the task with reasonably high accuracy.
Co-Authors -, A.Maddu -, R.Putri . Irmansyah . Masitoh . Mursyidah . Sucipto A M Fauzi A Maddu A. Ardian A. Maddu A. Subagio A. Subagio A.D. Husin A.Maddu - Abdul Djamil Husin Abdurahman Abdurrahman Abu Sonip Abu Sonip Ade Irma Ade Kurniawan Ade Kurniawan Ade Kurniawan Ade Kurniawan Ade Kurniawan Ade Kurniawan Adi, Langit Cahya Aditya Kurniawan Adnan Prasetyo Alamsyah Adrian Fadhillah Agnes Tiara Vinanda Agus Ismangil Agus Wahyana Anggara Agus Wahyana Anggara Agus Wahyana Anggara, Agus Wahyana Ahmad Khairul Reza Ahmad Yani Akhiruddin Akhiruddin Akhiruddin Maddu Aldi Destia Lesmana Alfi Afriliani Alif Musthafa Thariq Aljon Albertus Manotar Simbolon, Aljon Albertus Manotar Aminullah Aminullah Aminullah Aminullah Ana Fitriana Ana Fitriana Ana Fitriana Angga Khalifah Tsauqi Angga Khalifah Tsauqi Anis Munir Rukyati Anissa Tsalsabila Annisa Tsalsabila Antomi Saregar Ardian Arif Ari Firia Ari Setiawan ARI SETIAWAN Astri Wahyuningtyas Azka Zakiyyatuddin B. Sastri Baba Barus Bambang H. Trisasongko Bambang H. Trisasongko Bambang Herawan Bambang Herawan, Bambang Billi Rifa Kusumah Boedi Tjahjono Budi Harsono Budi Mulyanti Casnan, Casnan D Puspita Dea Amelia Saputri Demijati Demijati Dendy Handy Saputra Dendy Handy Saputra Dendy Handy Saputra Dendy Handy Saputra Desna Desna Deti Anggraeni Ekawati Dion Sanaha Dwi Lestariningsih Dwiky Agung Adi Nugroho Dyah R Panuju Dyah R. Panuju Dyah R. Panuju E. Ridwan E. Supriyanto Edy Sarwono Ella Rahmadani Endah Kinarya Palupi Erawan Kurniadi Erfiani Erfiani Erliza Hambali Erliza Noor Erna Rusliana Muhamad Saleh Erna Rusliana Muhamad Saleh Erni Apriliana Erni Aprilina Erni Aprilina Eti Rohaeti Eti Roharti Eva Musyafaah Evvy Kartini F Nawafi F. Huriawati F. S. Arsyad Fadhilah Chandra Fajrul Kamil Ramadhan Fanny Amalia Farida Huriawati, Farida Firmansyah Firmansyah Fitrah Hadi Firdaus Fitrah Hadi Firdaus Fitrah Hadi Firdaus Fitrah Hadi Firdaus, Fitrah Hadi Fitri Melinda Gagat Mughni Pradipta Gagat Mughni Pradipta Gagat Mughni Pradipta Gagat Mughni Pradipta H Syafutra H. Darmasetiawan H. Darmasetiawan H. Darmasetiawan H. DarmasetiawanArifin H. Hardhienata H. Sutanto H. Syafutra H. Syafutra Hadjomidjojo, Hartrisari Halimah Sa'diyah Hanedi Darmasetiawan Hannif Izzatul Islam Hannif Izzatul Islam Hannif Izzatul Islam Hannif Izzatul Islam Hari Wijayanto Hari Wijayanto Hartrisari Hadjomidjojo Hartrisari Hardjomidjojo Heriyanto Safutra Heriyanto Syafutra Herlan Darmawan Herlan Darmawan Hermawan Prasetya dan Taufik Djatna Hilal Fauzi Ramadhan Husin Alatas Imam Suyanto Indriyati Rahmi Setyani Ira Ukhtianingsih Ira Ukhtiningsih Ira Ukhtiningsih, Ira Irlian Nurmaniah Irlian Nurmaniah Irlian Nurmaniah Irlian Nurmaniah, Irlian Irmansyah . Irmansyah Irmansyah Irmansyah Irmansyah Irmansyah Irmansyah Irwan Meilano Irwan Meilano Ismangil, Agus Ivander Manuel Jajang Juansah Jenie, Renan Prasta Johan Iskandar Johan Iskandar Johansah Liman Kamelia Fikriah Khafit Pratama Hendratno Khusnul Yakin Koharudin Koharudin L. Nady La Isa Leni Ariyanti Lulu Lutfiah Lusia Anita Boru Sagala Lusia Anita Br. Sagala Lusia Anita Br. Sagala M. Barmawi M. Barmawi M. Barmawi M. Budiman M. Budiman M. Hikam M. Hikam M. Hikam M. Hikam M. N. Indro M.A. Idris Mahmud A. Raimadoya Mahmud A. Raimadoya Maria Evita Maria Evita Maya Risanti Maya Risanti Maya Risanti Maya Risanti, Maya Mersi Kurniati Meutia Awani Mitra Djamal Mitra Djamal Mochamad Iqbal Moh Yasin Mohammad Yasin Muhamad Syazali, Muhamad Muhamad Yani, Muhamad Muhammad A Fadhil Muhammad Ahyad Muhammad Fikri Fakhrurozi Muhammad Hikam Muhammad Hikam Muhammad Khalid Murtezha Hadijaya N. G. Pamungkas Nada Huwaidah Nadia Septiani Naufal Muharram Nurdin Nazopatul Patonah Har Nida Nabilah Nida Nabilah Nida Nabilah Nida Nabilah Nina Siti Aminah Nina Siti Aminah Noer A Indrawan Novitri Novitri P. Arifin P. Arifin P. Arifin P. Arifin P. Arifin P. Perdinan P. W. K. Anggraini Palupi, Endah Kinarya Purnawan Purnawan Putra, Heriansyah Putri Tarigan R Erviansyah R. D. Puspita R. Erviansyah R. Erviansyah R. Putri R.Putri - Raden Silfia Epriyanti Rahmad Junaidi, Rahmad Rahmat Nawi Siregar Ratih Dwi Septiani Retna Apsari Retno Dwi Jayanti Retno Dwi Kartika Sari Riani Eka Fitri Ridwan Siskandar Rizki Nurhikmah Rofiqul Umam Rohul Rizki Mubaroq Hartman Royyan Faizin S. Taking S.N. Jusoh Salahuddin Perdana Salamet Nurhimawan Sarah Aribah Miftahulfallah Sarah Nabilah Sejahtera Sejahtera Sensius Seno Sesar Husen Santosa Shelvie Nidya Neiman Sidikrubadi Sidikrubadi Sigit Ahmad Fatoni Sinta Puspita Apriliani Siswadi Siswadi Siti Aisyah Sofyan Sa'id Atsaurry Sofyan Sa'id Atsaurry Sofyan Said Sofyan Said Atsaurri Sri Mulatsih Stefiana Sondary Az Zahrah Sukirno Sukirno Sumarjono Effendy Supandi Supandi Suryanto, Wiwit Susi Susilawati T. Sumardi Talitha Alya Syaharani Tantan Taopik Ramlan Tantan Taopik Ramlan, Tantan Taopik Tantan Taopik Rohman TARUNI SRI PRAWAST MIEN KAOMINI ANY ARYANI DEDY DURYADI SOLIHIN Teguh Yogaraksa Tetinia Gulo Titin Yuliana Touwil Umrih Tun Tedja I U. Hashim Umam, Rofiqul Umi Trimukti Venas Miftah Hasan Wahyu Srigutomo Wahyu Srigutomo Wahyudi Wahyudi Wahyudi Wahyudi Wahyudianto, Benny Wasmen Manalu Widya Rahma Witri Desmulyani Yulia Christina Yulia Sani Yulia Sani Yulia Sani, Yulia Z. Jamal Z. Jamal Zahra Syahira Zulaeha Ma’bud