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Analisis Karakteristik Rewetting Dalam Celah Sempit Vertikal Untuk Kasus Bilateral Heating Berdasarkan Perubahan Temperatur Awal Plat

Jurnal Energi Dan Manufaktur Vol 5, No.1 April 2011
Publisher : Jurnal Energi Dan Manufaktur

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Abstract

Boiling heat transfer to analysis of effect main plate initial temperature to rewetting characteristics that arerewetting time, and pattern of rewetting were studied from transient temperature of surface plate. It is as result of experimentusing two vertical plate with 1 mm narrow gap. Debit and temperature of cooling water were controlled about 0,09 lt/s andsaturated temperature. The initial temperatures of main plate were changed from 500°C, 550°C, and 600°C. As results shownthat midle part of main plat has the highest value of rewetting time that is 310 second at 600°C initial main platetemperature, the lowest rewetting time is 40 second at 500oC initial main plate temperature on the bottom part of plate. Thehigher the plate initial temperature, the longer the rewetting time and variation of the plate initial temperatures can notinfluent the pattern of rewetting.

DESIGN OF A PROTOTYPE HYDRO COIL TURBINE APPLIED AS MICRO HYDRO SOLUTION

ASEAN Journal of Systems Engineering Vol 1, No 2 (2013): ASEAN Journal of Systems Engineering
Publisher : Master Program of Systems Engineering

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Abstract

This study deals with the effort to release new revolution of renewable energy concept. Key issue in generating hydro power from low head, low flow sources until now has been impractical, expensive in efficient and complex technology. The idea of using Hydro Coil instead of turbine gives an economic advantage that it is relatively cheaper. The apparatus allows us to exploit sides that would not be practical at all for conventional small hydroelectric power.Hydro Coil turbine in experimental prototype has been designed, built and tested. The turbine includes 4 inches acrylic with ribbon-like curved shape insert, which present a gradual curve of approximately 70 degrees from the axial flow of water progressing to a tightly curved angle perpendicular to the flow of water at the exit point. The gradual curve is used to reducing the axial velocity of water, thereby further as consequence of transfer energy from water to ribbon, thus the central axle and ribbon rotated. This rotation is initiated at the low frequency coil, with energy incrementally transferred as water, hitting the low frequency coil, turning the ribbon slowly, progressing gradually to higher frequency, tight coil where maximal energy to the transfer occurs.Characteristics and efficiency of Hydro Coil turbine can be identified after laboratory experimental already finished. Turbine efficiency in 92.93% of this prototype exceeds expectation in the experiments. It thus demonstrates the promising potential of Hydro Coil technology to extract power from incoming water flow in low head sources.

Pengujian 9 Algoritma Untuk Pemisahan Aliran Dasar : Studi Di Wilayah UPT PSDA di Madiun

Jurnal Teknik Sipil Vol 25, No 2 (2018)
Publisher : Institut Teknologi Bandung

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Abstract

AbstrakPenelitian ini bertujuan untuk menguji sembilan (9) algoritma pemisahan aliran dasar yang terdiri dari: enam (6) algoritma pemisahan berbasis filter digital (Recursive Digital Filter/RDF) dan tiga (3)  algoritma pemisahan berbasis grafis digital. Tahapan penelitian mencakup: (1) inventarisasi data,  (2) pengolahan data, (3) kalibrasi dan validasi, dan (4) evaluasi kinerja. Ke 9 metode algortima pemisahan tersebut dikalibrasi menggunakan data debit  harian dari tahun 1996  sampai tahun 2015.  Kalibrasi dilakukan per tahun pada sub-DAS Kalibrasi.  Kalibrasi dilakukan selama puncak musim kemarau (Juli sampai September) setiap tahunnya.  Pemilihan sub-DAS untuk kalibrasi mempertimbangkan kelengkapan data yang ada pada sub-DAS tersebut.  Selanjutnya parameter optimal ditentukan dari nilai rerata parameter tahunan. Kemudian, nilai RMSE, koefisien determinasi yang didapatkan dari scatter-plot, visualiasasi kurva-durasi-aliran, dan hidrograf aliran digunakan untuk mengevaluasi kinerja model.  Proses validasi pada ke 3 sub-DAS lainnya menggunakan nilai parameter yang didapat dari DAS kalibrasi. Hasil pengujian menunjukkan bahwa pada prnisipnya semua algoritma dapat  memisahkan aliran dasar dari debit total-nya. Namun demikian, algoritma  Lyne & Hollick and EWMA menghasilkan kinerja yang lebih baik dari ke tujuh algoritma lainnya.  Nilai rerata RMSE = 0,036 dan r2=0,87 untuk metode Lyne &Hollick.  Kinerja EWMA ditunjukan oleh nilai rerata RMSE = 0,041 and r2= 0,83. AbstractThis research aimed to evaluate nine (9) algorithmes for baseflow separation.  The six (6) recursive digital filter (RDF) and three (3) graphical separation algoritms were evaluated in this study. Four watersheds located at the administratuve boundary of  UPT PSDA Madiun were used. The methodology consists of (1) data inventory, (2) data processing, (3) calibration and validation, and (4) evaluating of models performance. The algorithms were calibrated using daily discharge data (from 1996 to 2015) for each year. The average values of the parameters obtained from calibration process were used to separate baseflow for the whole period record. Calibration watershed was determined by considering the completenes of recording discharge data (in this case: we use Nambangan sub-watershed). Validation process to others three (3) sub-watersheds conducted using parameter value from the calibrated watersheds. Then, RMSE, scatter plot, FDC and hydrograph were used to evaluate model performance during the dry season (July to September) both on calibrated and validated watersheds.  The result shows that pincipally all of the nine (9) algorithms can be used to separate baseflow from the total flow. Howerver, Lyne & Hollick and EWMA algortimes show the best performance compared to others algorithms. This conclusion based on the calculation of RMSE and R Squared (r2). The average value of RMSE =0,036 and R2=0,8 for Lyne &Hollick. Similarly, RMSE = 0,041 and r2= 0,83 for EWMA filter. 

Makna Rumah Bagi Masyarakat Jawa

Brikolase : Jurnal Kajian Teori, Praktik dan Wacana Seni Budaya Rupa Vol 1, No 2 (2009)
Publisher : Brikolase : Jurnal Kajian Teori, Praktik dan Wacana Seni Budaya Rupa

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Abstract

Communities on the island of Java considers the house like a man worthy to be appreciated and respected. Respect means honoring the house occupants inside the man. Houses must be respected because it is sacred. This statement was seen when the ceremonies at the time of making the residence. Before the house started its construction, the thing to do is to give offerings as gratitude to God. Typically these offerings in the form of crops if the various types of food and pray together like a newborn baby. This traditional ceremony is performed from the ancestors of the Javanese community. Construction of the house is sacred and holy. Implementation of deve-lopment chosen by the good days are tailored to the occupants and a good day for the people in Java. Because the house as a sacred container, then the Javanese people always treat her well and always clean so that their lives are always peaceful and prosperous future free from the calamity that has adversely affected the family. Keywords: Houses, Sacred and Holy, Offerings, Peace and Prosperity

Kursi Dan Eksistensinya Dari Masa Ke Masa

Pendhapa Vol 1, No 1 (2009)
Publisher : Pendhapa

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Abstract

A chair is a culture product as well as a social product. A chair is a means or a tool for sitting for human being. A chair has better luck than other kinds of furniture have. A chair has the most prestigious symbolic meaning which other furniture or designed artifact does not have. The word ‘Kedudukan’ (occupation) which comes from the root ‘duduk’ (to sit) means power so that it is no wonder that a chair becomes the symbol of power. A chair as a tool for sitting has developed to be a cross-cultural and country mass product since Industrial Revolution in England. A modern chair designed to be comfortable from an ergonomic standpoint, to be functional from the standpoint of shape, and to be economical from the standpoint of production has rapidly developed and many people are interested in it.Key words: chair, symbol of power, modern, shape

BENTUK DAN MAKNA MOTIF PORONG NAGA RAJA PADA INTERIOR PENDAPA AGENG TAMAN BUDAYA JAWA TENGAH DI SURAKARTA

Pendhapa Vol 3, No 2 (2012)
Publisher : Pendhapa

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Abstract

Artikel ini adalah hasil dari penelitian tentang motif Porong Naga Raja pada elemen estetikainterior Pendapa Ageng Taman Budaya Jawa Tengah di Surakarta. Permasalahan penelitianini terkait dengan ‘bentuk dan makna’, dimaksudkan untuk mengidentifikasi bentuk danmengungkap makna motif Porong Naga Raja. Mengungkap bentuk menggunakan KajianEstetika dengan pendekatan konsep desain berdasarkan struktur seni, yaitu: unsur rupa,meliputi unsur garis, bangun, rasa permukaan, warna, ruang dan waktu. Dasar-dasarpenyusunan atau prinsip disain, meliputi paduan harmoni-selaras, paduan kontras, paduanirama-repetisi, dan paduan gradasi-harmoni menuju kontras. Hukum penyusunan atauasas disain, meliputi kesatuan, keseimbangan, kesederhanaan, aksentuasi, dan proporsi.Mengungkap makna digunakan pendekatan estetika nusantara oleh Dharsono yaitu,seni merupakan tuntunan (mempunyai makna filosofi) sekaligus tontonan (bentuk yangterdiri dari pengulangan pola yang terdiri dari kumpulan motif, ditata dengan indah). Hasilpenelitian menunjukkan motif Porong Naga Raja muncul dengan tiga bentuk, yaitu: 1). Figurnaga dengan tampilan visual berupa kepala naga memakai mahkota raja. Keberadaannyamenempati bidang saka dan balok blandar. 2). Figur naga dengan tampilan visual nagasecara utuh, kepala naga dengan mahkotanya, badan posisi berdiri (seperti huruf S), danekor dengan ujung berbentuk kudhup bunga melati. Keberadaannya pada singup dan padalampu gantung utama pendapa ageng. 3). Figur naga dengan tampilan visual naga berkakiempat, mempunyai rumbai seperti jilatan ujung api pada keempat kaki dan ujung ekornya.Keberadaannya terdapat pada lampu payung terbalik. Pemaknaan figur naga dalam bentukmotif porong naga raja secara keseluruhan adalah mengenai ajaran kepemimpinan dansebagai falsafah yang mengandung nilai-nilai tuntunan dalam kehidupan.Kata-kata kunci: Motif Porong Naga Raja, tuntunan, tontonan.

ANALYSIS OF REWETTING TIME AND TEMPERATURE DISTRIBUTIONS DURING COOLING PROCESS IN VERTICAL RECTANGULAR NARROW CHANNEL

Jurnal Teknologi Technoscientia Vol 6 No 1 (2013): Vol 6 No 1 Agustus 2013
Publisher : LPPM IST AKPRIND Yogyakarta

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Abstract

Cooling process to analyze effect of gap size to rewetting time and temperature distributions were studied from transient temperature of surface plate. It as result of experiment using two vertical plate with the initial temperature about 600°C. Debit and temperature of cooling water are 0,09 L/s and saturated temperature. The gap sizes were changed from 1 mm, 2 mm, and 3 mm. As the results showed that the smaller the gap size, the longer the rewetting time.  Pattern of temperature distribution is similar at initial condition for all of gap sizes and the smaller the gap sizes, the longer the time of decreasing temperature.