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Analisis Resolusi Spasial Citra Ultrasonografi (USG) pada Arah Tangensial Radias Citra menggunakan Phantom Berbasis Silicon Rubber
Get PDFUltrasound is widely used in diagnostic imaging, therefore quality control(QC) of ultrasound images is important. One of the QC parameter is spatial resolution that can be analyzed by calculating the distance between two nearby object in the tangential direction of radiation. The image that is produced by the Curved Array transducer will produce a circular shaped image and the coordinates of the object isn’t in the cartesian coordinate system because it adapts to the surface of the transducer. The image must be transformed with a circle equation approach to calculate the distance between two nearby object. This study was using a Mindray 3D ultrasound model: DP-10 with Transducer model: 35C50EB, and phantom instruments made from a mixture of 99 ml silicon rubber and 1 ml catalyst. The acquisition data used a fixed frequency of 4.5 MHz with a gain variation of 168 dB, 182 dB, 202 dB and a depth variation of 3.3 cm, 4.9 cm, 5.7 cm. The result found that the measurement of objects in A area had an error of 0.8963%(0.087 mm),B area was 1.2979%(0.0779 mm), and C area was 2.6296%( 0.1183 mm). The values obtained still meet the standards set by American Association of Physicist in Medicine(AAPM)
Analysis of Influence of Abrasive Material Variation and Spray Pressure Variation in Coating Epoxy of Astm A36 Steel Toward Impact Resistance and Corrosion Rate
Get PDFCorrosion is a decrease in material quality caused by environmental influences. One of the methods commonly used to control corrosion is coating. In the coating process, the use of spray is the better method compared to roll and brush. Before coating is applied, the choice of abrasive material during the sand blasting process can determine the success of the coating. This research was conducted to analyze the effect of variations in abrasive material and spray pressure on the coating process of ASTM A36 steel material on its impact resistance, corrosion rate, and adhesion forces. Variation of abrasive material used were steel grit and silica. The spray pressure variations used were 2.5, 3.5, and 4.5 bar. The result of corrosion rate testing on variation with steel grit abrasive material and spray pressure of 4.5 bar has the lowest corrosion rate, with the value of 0.00124 mm/a. The highest adhesion strength test result of 9.07 MPa was obtained from variations with steel grit abrasive material and spray pressure of 4.5 bar. Impact test result using a variation with steel grit abrasive materials and a spray pressure of 4.5 bar yield the highest value, with the value of 2.287 joules
The Effect Analysis of Coating Thickness Variation and Mixture Composition of Magnesium – Flake Glass on Epoxy Coating on Abrasive Resistance, Adhesion Strength, and Prediction of Corrosion Rate of ASTM A36 Steel Plate
Get PDFSteel cannot be separated from the marine manufacturing industry. It is important to control the corrosion rate of steel used for offshore structures. The coating method can be used in mobilization areas and splash zones that have high corrosion rates due to sustained friction loads in the marine environment. The purpose of this study was to analyze the different in adhesion strength, abrasion resistance, and corrosion rate prediction of ASTM A36 low carbon steel plate with coating thickness variations of 300µm, 500µm, and 700µm and Magnesium Carbonate - Flake Glass mixture variations of 10%, 20%, and 30%. In the pull-off test, the highest value of adhesion strength was obtained from specimen with 300µm coating thickness and 10% Magnesium Carbonate - Flake Glass mixture with a value of 5.67 Mpa. The highest abrasion test value was obtained from specimen with 700µm coating thickness and 30% Magnesium Carbonate - Flake Glass mixture with a value of 0.91 Wear Cyces per Micrometer. Whereas in the three cells electrode test, the highest value was found at specimen with 700µm coating thickness and 30% Magnesium Carbonate - Flake Glass mixture with a value of 0,00010 mmpy
Analisis Periodisitas Gempa Bumi Diwilayah Kabupaten Lombok Barat Dengan Menggunakan Metode Statistik Dan Transformasi Wavelet
Get PDFAbstrak Penelitian ini adalah penelitian eksperimen. Dimana bertujuan untuk mengetahui yang pertama variasi nilai –a (aktivitas seismik) dan nilai –b (tingkat kerapuhan batuan), kedua mengetahui peridesitas gempa bumi dengan metode statistik dan transformasi wavelet, dan yang ketiga menganalisis hasil dari metode statistik dan transformasi wavelet diwilayah kabupaten Lombok Barat. Metode yang digunakan untuk menentukan periodesitas gempa bumi dalam penelitian adalah metode statistik dan transformasi wavelet. Metode statistik dengan prangkat lunak Zmap digunakan untuk menentukan nilai –, nilai –b, dan periodesitas gempa bumi. Pada metode transformasi wavelet digunakan skewness, transformasi Box Cox, dan transformasi wavelet continyu untuk menghitung periodesitas gempa. Penelitian ini menggunakan data dari BMKG dan National Earthquake Interntional Center (NEIC) untuk daerah antara episenter 1150.46-1160.20BT, dan 80.25 sampai dengan 80.55LS dari tanggal 22 Januari 2014 sampai 30 Oktober 2018. Analisis statistik menghasilkan parameter yang berkaitan dengan kondisi seismik (kegempaan) dan tektonik daerah penelitian. Parameter tersebut terdiri atas nilai – sekitar 5,5-2, nilai –b 0,9-1,8. Kedua parameter tersebut menunjukkan jarangnya terjadi gempa bumi dan cukup tingginya stress pada lempeng. Periodesitas berdasarkan hasil analisis statistik adalah sekitar 40-60 tahunan untuk magnitude 5,5 SR. Dengan metode transformasi wavelet diperoleh periodesitas sebesar 30 tahun dan 60 tahun untuk gempa dengan magnitudo 5,5 SR. Sehingga bisa disimpulkan bahwa hasil ini menunjukkan bahwa kedua metode tersebut menghasilkan nilai periodesitas yang hampir sama. Abstract This research is experimental research. Where the aim is to find out the first variotion of the a- vuale and the –b vuale, the second is to know the earthquake frequency whit the statistical method and wavelet transformation. And the third to analyze the results of the statistical method and wavelet transformation in the west Lombok regency. The method used to determine the earthquake periodicity in the study is the statistical method and the wavelet transformation. Statistical methods with Zmap sofwer are used to determine –a values, -b vuales, and earthquake periodicity. The wavelet transformation method uses skeweness, Box Cox transformation, and continyu wavelet transformation to calculate earthquake periodicity. This study uses data from BMKG and the National Earthquake International Center (NIEC) for the area between the epicenter of 1150.46-1160.20 BT, and 80.25 to 80.55 LS from 22 January 2014 to 30 October 2018. Statistical analysis produces parameters related to saismic conditions (seismic) and tectonic research area. The parameter consists of a vuale –a around 5,5 – 2 the –b vuale of 0,9 – 1,8. Both of these parameters shwo a rare earthquake and quite high stress on the plate. Periodicity based on the results of statistical analysis is around 40-60 years for magnitude 5,5 SR. with the wavelet transformation method, the periodecity of 30 years and 60 years is obtained for earthquakes with magnitude 5,5 SR. these results indicate that the two methods produce almost the same periodecity values.
Model Matematika Persaingan Dua Spesies dengan Toksisitas dan Pemanenan Selektif
Get PDFPersaingan merupakan interaksi biologi antar makhluk hidup untuk bersaing mendapatkan sumber energi yang terbatas, misalnya makanan yang dibutuhkan untuk tumbuh dan bertahan hidup. Beberapa spesies mempunyai strategi tersendiri dalam bersaing, diantaranya adalah kemampuan mengeluarkan racun. Pada jurnal ini, dikaji dua model predator-prey yang dipengaruhi oleh adanya toksisitas dan pemanenan selektif. Model pertama mengkaji model persaingan dua spesies dengan adanya toksisitas dan pemanenan selektif, sedangkan model kedua mengkaji model persaingan dua spesies dengan adanya toksisitas dan pemanenan selektif dengan Holling tipe III. Dari model pertama diperoleh 4 titik setimbang yaitu dan Dari model kedua juga diperoleh 4 titik setimbang, yaitu dan . Titik setimbang dan tidak stabil, sedangkan , dan stabil dalam kondisi tertentu. Hasil simulasi numerik menunjukkan bahwa kedua spesies pada model kedua mengalami peningkatan dibandingkan dengan model pertama. Hal tersebut dikarenakan adanya kecenderungan untuk mencari musuh yang lain ketika jumlah musuh mulai berkuran
Technical-Economic Analysis of Photovoltaik Reverse Osmosis Planning for Fulfillment of Fresh Water System on Ro-Pax Ship
Get PDFThe need for fresh water in the world of industry is increasing with the rapid development of the global industry. The shipping industry is having a significant impact as part of a global industry concerning the sector of freshwater demand on ships. Freshwater supplies on ro-pax vessels are very important because they are the source of crew and passenger life when ships sail. Fulfillment of freshwater needs on a ro-pax vessel is made in a conventional system by filling clean water into a freshwater tank from the port. In this final project will be analyzed technical and economical on designing fresh water system using reverse osmosis system with solar panel as power supply and compare it with conventional system on ship KM. SABUK NUSANTARA 56. This Final Project includes installation design, size of fresh water tank, amount of cargo, investment cost and operational cost. The conclusion obtained in this final project is a reverse osmosis (RO) system with solar panels as a very efficient power supply when applied to ro-pax ships such as ships KM SABUK NUSANTARA 56 because with this system the ship is able to produce their own fresh water, the size of the freshwater tank is smaller, for new shiploads can be increased. For the percentage of total cost of fresh water needs is dearer about 52 percent compared to conventional system and payload value increased 29.2 percent compared to conventional system
COVER
No full textCover of International Journal Of Marine Engineering Innovation And Research Volume 1 No.
Perancangan PLTA Pico-Hydro menggunakan Tabung Hydrocyclone dan Turbin Kaplan melalui Solusi Numerik Runge-Kutta
Get PDFPerancangan PLTA Pico-Hydro menggunakan turbin Kaplan dilakukan dengan memanfaatkan aliran air berbentuk tabung Hydrocyclone. Turbin Kaplan dapat bergerak dengan kecepatan putaran mengikuti kecepatan rotasi fluida sehingga dapat dianalisis sistem gerak konverternya. Perumusan persamaan gerak yang diperoleh melalui penerapan persamaan Euler-Lagrange untuk menghasilkan persamaan diferensial. Persamaan tersebut diterapkan dengan metode Runge-Kutta yang merupakan salah satu metode pendekatan iterasi dengan solusi numerik. Sistem konverter gerak initerdiri dari 5 roda dengan roda ke-1 seporos dengan roda ke-2. Roda ke-2 dan ke-3 terhubung secara serantai dan roda ke-4 saling terhubung dengan roda ke-5 untuk menghasilkan pembangkit listrik. Hasil yang diperoleh aliran air dapat memutarkan turbin kaplan dengan gaya sebesar 50 N. Kecepatan putaran sudut maksimum sebesar 5500 rad/s pada roda ke-5. Kecepatan putaran roda-roda pada sistem konverter akan semakin meningkat seiring dengan bertambahnya waktu