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KEMAMPUAN TEMPURUNG KELAPA SEBAGAI PANEL AKUSTIK REFUSER (RESONATOR - DIFUSER) DALAM MENYERAP DAN MENGISOLASI BUNYI
Get PDFOne of requirements of proper hearing condition in a auditorium is the presence of uniform sound distribution. The uniform sound distribution can be achieved by using additional reflectors. However, the addition of reflectors in wide room, such as auditorium, leads to undesirable echoes. Echoescan could be improved by adding absorbent materials. The consequence of this is an emerge of various sound distribution. Therefore, this article performs the combination of two functions of a material, i.e as resonator and diffuser (also known as ‘refuser’). Coconut shells are cut into rectangles with a size of 3cm x 3cm, and also given holes in the middle of about 1 mm and arranged into mosaic. Then, mosaic is combined with Rockwool to be a refuser. The tests involve two types of measurements, i.e determining the value of the absorption coefficient (α) and noise reduction (NR). These test method uses the impedance tube method to determine the ability of the refuser to absorb and isolate the sound. The results shows that the addition of the mosaic (coconut shells) is able to double the value of α to 0.64 at a frequency of 250 Hz. In other words, the refuser could behave as a resonator. Furthermore, the refuser is able to increases the NR value at frequencies above 1000 Hz (30-40 dB) and also able to be used as absorber sound at low frequency (250 Hz) and in higher frequencies (≥ 1000 Hz)
Perancangan Desain Interior Creative Hub dengan Pendekatan Communal Space
Get PDF“Salah satu hal yang harus diperhatikan oleh kota adalah kenyataan bahwa talenta menguatkan ekonomi, sedangkan diservitas dan kebutuhan menarik talenta untuk datang” (Florida, 2005:139). Berdasarkan hasil survey dalam bentuk kuisioner yang ditujukan pada remaja aktif (18th-24th) di kota Bandung, dapat disimpulkan bahwasannya seorang remaja memiliki ketertarikan dalam melakukan interaksi untuk memenuhi kebutuhan sosisalnya. Pengguna yang dimaksud pada perancangan ini adalah Gen Z pada usia produktivitas (remaja). Generasi Z pada usia tersebut memiliki karater antara lain lebih tidak fokus, multitasking, lebih individual, berfikiran lebih terbuka, tertarik untuk berinteraksi, lebih reliabilitas, memiliki cara yang lebih effisien (non-tradisional atau caranya sendiri). Pengguna dari perancangan ini memerlukan ruang yang dapat digunakan sebagai media berinteraksi dan melakukan brainstorming serta berkolaborasi. Seperti halnya yang disampaikan Florida “diservitas dan kebutuhan menarik talenta untuk datang”. Maka dibutuhkannya Communal Space yang memiliki aspek fungsional, estetik, interaksi sosial, bertukar pikiran, mampu mengakomodasi interaksi antara berbagai kelompok sosial dan etnis. Berdasarkan Composing Architecture and Interior Design by Simos Vamvakidis menyatakan area pada bagian tengah sebuah denah perancangan akan menjadi pusat perhatian atau dengan kata lain untuk mengorganisasikan sebuah ruang maka diperlukan elemen utama yang diposisikan pada pusat ruangan. Pada perancangan pada Communal space juga menerapkan teori yang disampaikan oleh Simos Vamvakidis mengenai Collective Space, dapat dikatakan Collective Space dan Communal Space merupakan tipe ruangan yang memiliki tujuan sama, yaitu sebagai area atau ruang “space of pause” di dalam bangunan.Kata kunci: communal space; creative hub; gen Z; composing space ABSTRACT "One of the things that must be considered by cities is reality as a talent to strengthen the economy, while diversity and the attractive need for talent to come" (Florida, 2005: 139). Based on the results of the survey in the form of questionnaires conducted on active adolescents (18-24) in Bandung, it can be concluded that teenagers are interested in interacting to meet their sausage needs. Users approved in this design are Gen Z in productive age (teenagers). Generation Z at this age has characters who are more out of focus, multitasking, more individual, think more openly, more interested in being facilitated, more reliable, having more efficient ways (non-traditional or can be used alone). Users of this design need space that can be used as a medium of collaboration and brainstorming and collaborating. As exciting as it was conveyed Florida "diversity and interesting needs of talent to come". Then Communal Space Required which has functional, aesthetic aspects, social interaction, exchange of ideas, is able to accommodate interactions between various social and ethnic groups. Based on the Arrangement of Architecture and Interior Design by Simos Vamvakidis stating the area in the middle of the design plan will be the center of attention or other words to organize a space so that the elements positioned at the center of the room are needed. In the Communion Room Design Room also applies the theory conveyed by Simos Vamvakidis regarding Collective Space, it can be agreed that Collective Space and Communal Space are the types of rooms that have the same purpose, namely as "Space to Pause" in the building. Keyword: communal space; creative hub; gen Z; composing spac
DUCTILITY EVALUATION OF REINFORCED CONCRETE COLUMN MADE OF NORMAL- TO HIGH-STRENGTH CONCRETE UNDER CONSTANT AXIAL LOAD LEVEL COMBINED WITH FLEXURAL LOADING USING NONLINEAR SECTIONAL FIBER BASED MODEL
Get PDFThis study presents the ductility evaluation of reinforced concrete column made of normal-strength material using various empirical stress-strain model with nonlinear sectional fiber based analysis. The purpose is to evaluate the confinement requirement for reinforced concrete column under high axial load level. The concrete strength considered in the analysis are varies from 30 to 70 MPa while the steel reinforcing bar yield strength considered is only 400 MPa. The ductility is evaluated by using the customized ductility index measurement. The ratio of the concrete cover to the concrete core is set to 0.1 but not more than 40 mm. Attard and Setunge’s concrete constitutive model is used in this investigation. Cover spalling behavior is considered in the analysis by including the restrained shrinkage effect on the concrete strength and the softening behavior. From this study, it was found that extra confinement is necessary to maintain the expected minimum level of ductility
Utilization of Mixture of Teak Wood Sawdust and Bagasse Fiber using Treatment of Fiber Variations and Alkali NaOH Immersion as A Refrigerator Insulation Material
Get PDFThis research modified the insulation of coolbox material by utilizing a mixture of teak wood sawdust (Tectona grandis L.f.) and previously immersed bagasse fiber (Saccharum officinarum) into an alkali NaOH solution to improve the mechanical properties of the fiber and reduce the value of material thermal conductivity. The most optimal test and analysis results were obtained by composing 50% teak wood sawdust with 50% of previously immersed bagasse fiber in an alkali NaOH solution at a level of 15%. The obtained conductivity value is 0.2907 W / mK, the density is 0.4901 gram / cm3. Experiments on changes in temperature of ice, fish, and coolbox chamber as well as experiments on the duration of fish preservation in the coolbox with variations in the composition of straight fibers have better performance compared to the variation of random fiber which is able to preserve fish for 34 hours with minimum temperature of 0, 2 ° C. For fishing duration of two days, coolbox with a variety of straight fiber has almost the same performance as coolbox made from styrofoam and has the potential to replace styrofoam because it is more environmentally friendly
Analisis Prioritas Pemeliharaan Jalan Kabupaten Karanganyar Metode Analytical Hierarchy Process (AHP)
Get PDFPersoalan keterbatasan dana seringkali menjadi kendala dalam menentukan prioritas pemeliharaan jalan, termasuk pada Kabupaten Karanganyar. Selama ini Dinas Bina Marga menentukan urutan prioritas jalan hanya berdasarkan pada penilaian subyektif. Oleh karena itu maka perlu adanya suatu metode mengenai penentuan prioritas jalan secara objektif yang akan dilakukan pemeliharaan agar tepat sasaran. Dalam Penelitian ini mengusulkan Metode Analytical Hierarchy Process (AHP) sebagai penentu urutan prioritas pemeliharaan Jalan di Kabupaten Karanganyar. dengan kriteria yang digunakan adalah kondisi jalan, Lalu Lintas Harian (LHR), lebar jalan, biaya penanganan, dan fungsi tata guna lahan. Dari hasil analisis didapatkan urutan kriteria yang paling berpengaruh adalah kriteria biaya pemeliharaan, kondisi jalan, LHR, fungsi tata guna lahan, dan lebar jalan. Adapun urutan prioritas pemeliharaan jalan yaitu jalan Tasikmadu-Dagen, Sukosari - Jumantono, Jagan-Lemahbang, Beruk-Wonokeling, Matesih-Tegalgede, Jendral Sudirman, Jatiyoso-Jatisawit, Tepus-Sentul, Ngasem-Paseban, dan Jalan Wonosari-Kragan
Analisa Lokasi dan Perancangan Fasilitas Sisi Udara Bandar Udara Bali Utara
Get PDFJumlah pergerakan Bandara Ngurah Rai meningkat 6,1 persen antara tahun 2016-2017. Berdasarkan RTRW Provinsi Bali akan dibangun Bandara Bali Utara di daerah Kubutambahan, Buleleng. Oleh karena itu, perlu adanya evaluasi apakah lokasi pembangunan Bandara Bali Utara sesuai dengan Kawasan Keselamatan Operasional Penerbangan dan juga merencanakan fasilitas sisi udara pada Bandara Bali Utara. Pengumpulan data angin dari tahun 2014 hingga 2018 didapat dari Iowa State University Enviromental Messonet. Dari analisa data didapat bahwa arah runway adalah 90O. Pada perencanaan fasilitas sisi udara dilakukan pengumpulan data pergerakan penumpang dan pesawat dari tahun 2012 hingga 2016 pada Bandara Ngurah Rai yang didapat dari PT. Angkasa Pura 2 dan Kementerian Perhubungan Udara, kemudian dilakukan regresi untuk mendapatkan data pergerakan pada 20 tahun rencana. Dari data historis tersebut dikalikan dengan presentase demand pergerakan penumpang dan pesawat di Bandara Bali Utara yang didapat dari perbandingan tingkat pertumbuhan penghunian hotel di Bali Utara. Presentase yang didapat yakni sebesar 43,3% sehingga pergerakan penumpang pada 20 tahun rencana sebesar 18.035.382 penumpang dan pergerakan pesawat 100.194 pergerakan. Pesawat rencana yang digunakan adalah Airbus A330-200, karena pesawat ini merupakan pesawat terbesar yang beroperasi di Bandara Ngurah Rai. Dari perhitungan didapatkan pergerakan pesawat saat jam sibuk ditahun 2038 sebesar 18 pergerakan per jam. Dan presentase pesawat yang beroperasi saat jam sibuk adalah kelas B:10%, kelas C:32%, kelas D:58%. Pada perencanaan ini didapatkan panjang runway adalah 3700 m dengan lebar runway 66 m. Dimensi lebar taxiway 25 m dan lebar bahu tiap sisinya sebesar 10 m. Letak exit taxiway sepanjang 3100 m dihitung dari kedua ujung runway dengan sudut 90O, dan luas apron sebesar 106.300 m2. Pada perencanaan tebal perkerasan menggunakan aplikasi FAARFIELD. Didapatkan bahwa tebal perkerasan lentur sebesar 0,5 m – 2,5 m dan tebal perkerasan kaku sebesar 0,8 m – 1 m
Development of Cutter Head Design in Cutter Suction Dredger with Thickness and Pitch Variation
Get PDFThe need for dredgers for the shallow water in the sea with a very high level of siltation on the coast of Indonesia is a factor worth considering. For example, coastal areas in Ujung Pangkah sub-district, Gresik district, East Java province. The choice of the area is due to the many institutions and corporations that are back and forth utilizing these waterways. But the main obstacle to making a Cutter Suction Dredger (CSD) is almost all the equipment needed is imported, for example, the main equipment is the cutter head. Therefore looking at the needs, economics and technology factors, this paper will discuss the cutter head design. Available data is a request from the owner, 40KW power cutter head; 1000mm cutter diameter; 30rpm rotation. The force distribution given 5950 N is in accordance with the dredging condition which is to have a strong material tension to be estimated to work at a relatively Soft density of <100 Mpa and Medium around 100Mpa - 170Mpa. The expected results of this design are to obtain a proportional design before the production process and to function at a minimum according to specifications. The usefulness of this design really hopes to be followed up to the production stage and can be applied
A Genetic Algorithm with Best Combination Operator for the Traveling Salesman Problem
Get PDFIn this research, we propose a genetic algorithm with best combination operator (BC(x,y)O) for the traveling salesman problem. The idea of best combination operator is to find the best combination of some disjoint sub-solutions (also the reverse of sub-solutions) from some known solutions. We use BC(2,1)O together with a genetic algorithm. The proposed genetic algorithm uses the swap mutation operator and elitism replacement with filtration for faster computational time. We compare the performances of GA (genetic algorithm without BC(2,1)O), IABC(2,1)O (iterative approach of BC(2,1)O), and GABC(2,1)O (genetic algorithm with BC(2,1)O). We have tested GA, IABC(2,1)O, and GABC(2,1)O three times and pick the best solution on 50 problems from TSPLIB. From those 50 problems, the average of the accuracy from GA, IABC(2,1)O, and GABC(2,1)O are 65.12%, 94.21%, and 99.82% respectively
The Effect of Nitrogen Stress And Photoperiode on Growth and Fatty Acid Content of Nannochloropsis sp.
No full textEnergy consumption increases from year to year and 95% is fulfilled by fossil materials which are limited, so that a replacement energy source is needed. Biodiesel is a fuel from renewable sources such as plants or animals. Biodiesel from Jatropha curcas and palm oil has been produced but oxidation is low in cold temperatures and long time to production. On the other hand, Nannochloropsis sp., as marine microalgae can produce lipids as biodiesel material reaches 90% of the biomass dry weight in stress condition, It’s higher than lipid that produced by Jatropha curcas (35% DW) and palm (75,6% DW). Nannochloropsis sp. also short growth, easily propagated. Production of lipids and TAGs of Nannochloropsis sp. can be engineered based on nutrient, temperature, aeration, salinity, photoperiod. This study aims to examine the effect of nitrogen stress and photoperiode on biomass, chlorophyll content, fatty acid profile, content of TAG. Nannochloropsis sp. cultured from the starter then cultured in variation of nitrogen stress and phoroperiode. In the last exponential, culture analized in quantitative to get the biomass and chlorophyll content. Fatty acid and TAG analized by qualitative. The interaction between nitrogen and photoperiode did not affect the biomass of Nannochloropsis sp. but it affects the chlorophyll content where the chlorophyll content of P14 (N100, 16: 8) is 7.367 mg/L. It is not significantly different from the treatment P6 (N25, 24: 0) of 3.339 mg/L and treatment P15 (N100, 24: 0) 5.665 mg/L. All cultures with a treatment combination showed triacylglycerol content. The results of the treatment of fatty acid profiles P14 (N100, 16: 8) contain more varied fatty acids compared to P1 (N0, 12:12), P2 (N0, 16: 8), P8 (N50, 62: 8), P10 (N75 , 12:12) which consists of lauric acid, hexagonal acidrionate, palmitic acid, linoleic acid, oleic acid, stearate acid, eicosanoic acid.The result showed that the treatment of nitrogen stress and photoperiode affecting the growth and fatty acid content of Nannochloropsis sp
Analisis Kekuatan dan Stabilitas Tanah Lempung Organik Artifisial Untuk Perencanaan Jalan dengan Beban Lalu Lintas Tinggi
Get PDFTanah lempung organik merupakan salah satu jenis tanah lempung yang memiliki daya dukung rendah dan potensi pengembangan (swelling) yang besar. Kandungan bahan organik yang melewati batas maksimum akan mereduksi kekuatan dan stabilitas dari proses stabilisasinya. Tujuan penelitian ini untuk mengetahui pengaruh penggunaan abu vulkanik Gunung Kelud dan semen Portland terhadap kekuatan dan stabilitas tanah lempung organik artifisial serta tebal perkerasan rencana yang digunakan. Metode penelitian ini dibagi menjadi 2 tahapan yaitu tahap pra-stabilisasi dan tahap stabilisasi. Pada tahap pra-stabilisasi, tanah lempung organik dicampur dengan masing-masing 3 variasi kadar abu vulkanik, kemudian dilakukan pemeraman selama 3 hari. Selanjutnya, pada tahap stabilisasi, tanah hasil campuran tersebut ditambahkan masing-masing 5% semen Portland, lalu kembali diperam selama 3 hari. Kadar air optimum mengalami penurunan dari 33,696% menjadi 29,586%, berat volume kering mengalami peningkatan dari 1,319% menjadi 1,351%, CBR rendaman mengalami peningkatan dari 2,87% menjadi 9,77%, dan potensi pengembangan mengalami penurunan dari 2,36% menjadi 0,45%