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"[ABSTRAKTelah dibuat sistem volumetric magnetic induction tomography (VMIT) menggunakan 8 koil pemancar dan 8 koil penerima. Adanya eksitasi sinyal sinus pada koil transmitter menimbulkan medan magnet yang berubah-ubah sehingga menimbulkan ggl induksi pada koil receiver. Besarnya medan magnet induksi ini juga dipengaruhi oleh permeabilitas medium antara koil pemancar dan penerima. Simulasi COMSOL dan MATLAB pada sistem VMIT 8 koil menunjukkan bahwa dengan menggunakan algoritma ILBP objek berbentuk bola dengan permeabilitas logam besi dapat direkonstruksi sehingga menghasilkan citra yang serupa. Dari hasil simulasi ini kemudian dibuat prototipe sistem akuisisi data VMIT. Prototipe sistem VMIT yang dibuat diuji coba untuk mengenali objek logam berbentuk silinder seperti kaleng cat semprot dan besi pejal. Hasil rekonstruksi citra dapat mendeteksi keberadaan objek logam dengan diameter minimal 3 cm dan panjang 10 cm, namun citra masih terlihat kurang jelas. Secara keseluruhan pengambilan data dengan menggunakan prototipe sistem VMIT ini cukup stabil yaitu dengan rata-rata persentase standar deviasi adalah 0,75%.

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ABSTRACTVolumetric magnetic induction tomography (VMIT) system has been developed by using 8 coils as transmitter and 8 coils as receiver. The existence of sine excitation signal in the transmitter coil cause magnetic field changing, it causing emf at the receiver coil. The magnitude of the magnetic field induction is also influenced by the permeability of the medium between the transmitter and receiver coils. COMSOL and MATLAB simulation of VMIT 8 coil systems indicate that by using ILBP algorithms, ball shaped object with ferromagnetic materials (iron) can be reconstructed to produce a similar image. According to the simulation results are then made prototypes of a data acquisition system of VMIT. The prototype of VMIT system can recognize a cylindrical objects of ferromagnetic materials such as solid iron and tin paint sprayer with 10 cm of length and minimum 3 cm of diameter. The results of image reconstruction can indicate the presence of the cylindrical object. Overall the collection of data by using a prototype of VMIT system is quite stable and the average standard deviation is 0.75%., Volumetric magnetic induction tomography (VMIT) system has been developed by using 8 coils as transmitter and 8 coils as receiver. The existence of sine excitation signal in the transmitter coil cause magnetic field changing, it causing emf at the receiver coil. The magnitude of the magnetic field induction is also influenced by the permeability of the medium between the transmitter and receiver coils. COMSOL and MATLAB simulation of VMIT 8 coil systems indicate that by using ILBP algorithms, ball shaped object with ferromagnetic materials (iron) can be reconstructed to produce a similar image. According to the simulation results are then made prototypes of a data acquisition system of VMIT. The prototype of VMIT system can recognize a cylindrical objects of ferromagnetic materials such as solid iron and tin paint sprayer with 10 cm of length and minimum 3 cm of diameter. The results of image reconstruction can indicate the presence of the cylindrical object. Overall the collection of data by using a prototype of VMIT system is quite stable and the average standard deviation is 0.75%.]"

"ECVT (Electrical Capacitance Volume Tomography) merupakan teknik pencitraan yang memanfaatkan nilai kapasitansi dari objek berbentuk volum yang dikelilingi oleh multi sensor. Sensor-sensor yang mengelilingi objek tersebut mengukur nilai kapasitansi listrik yang dipengaruhi oleh distribusi permitivitas yang terdapat di dalam objek yang kemudian direkonstruksi dengan algoritma yang sesuai untuk mendapatkan citra dengan menggunakan software MATLAB R2008a. Sedangkan pembuatan model objek jaringan tumor dan sensor kanker payudara diperoleh melalui FEM (finite element method) atau dikenal dengan metode elemen hingga dengan menggunakan software COMSOL Multiphysics 3.4. Persoalan Ill-Posed yang muncul pada proses rekonstruksi, ditangani dengan menggunakan metode ILBP atau Landweiber equation. Pengujian sensor kanker payudara yang berbasis kapasitansi listrik ini dilakukan pada objek phantom yang menyerupai jaringan payudara manusia dengan menggunakan 24 elektroda yang dipasang disekeliling objek. Dari hasil eksperimen dapat ditunjukan bahwa citra distribusi permitivitas hasil rekonstruksi memiliki pola yang sama dengan distribusi permitivitas pada objek simulasi dan dapat mendiagnosis secara fisik adanya gejala kanker payudara.

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ECVT (Electrical Capacitance Volume Tomography) is an imaging technique that utilizes the capacitance value of the volume-shaped object surrounded by a multi-sensor. Sensors which surround the object is to measure the value of electric capacitance is influenced by the permittivity distribution contained in the object which is then reconstructed with the appropriate algorithm to obtain the image using the software MATLAB R2008a. While making the object model of breast tumor tissue and the sensor is obtained through FEM or known by the Finite Element Method using the software COMSOL Multiphysics 3.4. Ill-posed problems arising in the reconstruction process, handled using methods ILBP or Landweiber equation. Tests based breast cancer sensor electrical capacitance is carried out on a phantom object that resembles human breast tissue using 24 electrodes placed around the object. From the experimental results can be shown that the image of the results of reconstructing the permittivity distribution has the same pattern with the distribution of permittivity on the object model and can diagnose physical symptoms of breast cancer."