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Uji Diagnostik Pemeriksaan Osteosklerotik Tulang dengan Sistem Radiografi Digital

MEDIA MEDIKA INDONESIANA 2011:MMI Volume 45 Issue 3 Year 2011
Publisher : MEDIA MEDIKA INDONESIANA

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Abstract

ABSTRACTDiagnostic test of bone osteosclerotics examination using digital radiography systemBackground: The interpretation of a conventional röntgen images have a high degree of subjectivity due to the limitation of humansight. The computationally detection help establish the accuracy of diagnosis of the radiologist. According to our knowledge, there has not been previous research on this issue in Indonesia. The research was aimed to examine a Matlab based software to determine the diagnostic value in the diagnosis of osteosclerotic bone.Methods: This study was a diagnostic test which was conducted in Radiology Department of Dr. Kariadi Hospital Semarang, Dr.Sardjito Hospital Yogyakarta and Bethesda Hospital Yogyakarta, April to August 2009. The radiographs of bone osteosclerotic resulted from computed radiography (CR) test results were taken consecutively, interpreted by a radiologist which was supported by the Anatomical Pathology Laboratory examination as a gold standard. Afterwards these steps were done respectively: classify patients as a normal or osteosclerotic patients based on the cut off point that was determined, calculate the value of the diagnostic by analysis of 2x2 tables, determine the area under the curve (AUC) by the procedure of receiver operating characteristic (ROC), anddetermine the optimal of COP (cut off point) using ROC procedure.Results: From the results of diagnostic tests of bone radiographs these following parameter values was obtained: AUC value of 97.6% (95% CI: 94.4%-100%), the optimal cut off point for bone oseosclerotic COP ≥1.05 with a sensitivity value of 93.0% and a specificity of 89.1%. Suitability kappa value of 0.818 K (95% CI: 0.757 to 0.879).Conclusion: The radiographic examination of the results of CR using Matlab-based software can be used to diagnose boneosteosclerotic with high sensitivity and specificity.Keywords: Bone osteosclerotic, röntgen images, optimal of COP, Matlab softwareABSTRAKLatar belakang: Pembacaan foto röntgen secara konvensional memiliki tingkat subyektivitas tinggi karena keterbatasan indrapenglihatan manusia. Pendeteksian secara terkomputasi membantu menegakkan diagnosis para radiolog. Sebagaimana diketahui, belum ada penelitian sebelumnya mengenai masalah ini di Indonesia. Penelitian ini bertujuan menguji perangkat lunak berbasis Matlab untuk menentukan nilai diagnostik pada diagnosis tulang osteosklerotik.Metode: Penelitian ini adalah uji diagnostik yang dilakukan di Bagian Radiologi RSUP Dr. Kariadi Semarang, RSUP Dr. SardjitoYogyakarta dan Rumah Sakit Bethesda Yogyakarta, April-Agustus 2009. Radiograf osteosklerotik tulang hasil pemeriksaan CR (computed radiography) diambil untuk sampel secara konsekutif, kemudian diperiksa oleh radiolog yang didukung oleh pemeriksaan Laboratorium Patologi Anatomi sebagai baku emas. Tahapan yang dilakukan berturut-turut adalah: mengelompokkan pasien sebagai osteosklerotik dan normal berdasar titik potong yang ditentukan, menghitung nilai diagnostik dengan tabel analisis 2x2, menentukan AUC (area under the curve) dengan prosedur ROC (receiver operating characteristic), dan menentukan COP (cut off point) optimal dengan prosedur ROC.Hasil: Hasil uji diagnostik radiograf tulang diperoleh nilai-nilai parameter sebagai berikut: nilai AUC adalah sebesar 97,6% (IK 95%: 94,4%-100%), titik potong optimal untuk osteosklerotik tulang COP ≥1,05 dengan nilai sensitivitas sebesar 93,0% dan spesifisitas sebesar 89,1%. Nilai kesesuaian kappa K sebesar 0,818 (IK 95%: 0,757-0,879).Simpulan: Pemeriksaan radiografi hasil CR menggunakanperangkat lunak berbasis Matlab dapat digunakan untukmendiagnosis osteosklerotik tulang dengan sensitivitas danspesifisitas tinggi

Uji Diagnostik Pemeriksaan Tulang Osteolitik Berbasis Intensitas Citra Digital

MEDIA MEDIKA INDONESIANA 2012:MMI VOLUME 46 ISSUE 1 YEAR 2012
Publisher : MEDIA MEDIKA INDONESIANA

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Abstract

Diagnostic test of osteolytic bone examination based on digital image intensityBackground: The visual examination of bone radiographs using digital computed radiography (CR) is an examination for the diagnosis of bone-metastatic cancer. The subjectivity of interpretation of bone radiographs may lead to doctor’s doubt in making decision to treatment patients with bone-metastatic cancer. Software Matlab-based computer application program makes a standard method to organize the results of bone radiographs. The objective of this study is to develop a software based on Matlab to analyze the diagnostic values, and to determine the optimal of cut off point to diagnose of osteolytic bone.Method: The researches data are collected from Department of Radiology of three hospitals i.e. Dr. Kariadi Hospital Semarang, Dr. Sardjito Hospital and Bethesda Hospital Yogyakarta. This research was carried out during four month from April to August 2009. Radiographs of osteolytic bone interpreted by radiologist were compared with PA examination result of the osteolytic bone which were viewed as the gold standard. The steps in this study i.e. patients are classified as a normal or osteolytic bone patients based on the cut off point that had been determined, calculate the value of the diagnostic test using 2x2 tables, determined the area under the curve (AUC) by the procedure of receiver operating characteristic (ROC), and determined the optimal of cut off point.Result: The results of study show that the diagnostic test for osteolytic bone by using Matlab-based software has sensitivity of 0.88, specificity of 0.891, positive expected value of 0.897, negative expected value of 0.950 and the cut off point at 0.93, while, the value of area under the curve (AUC) is 94% (95% CI: 89.7%-98.3%), and the accuracy is 0.881 for the case of osteolytic bone.Conclusion: Matlab-based software being used for diagnosing osteolytic bone has relatively high sensitivity and specificity.Keywords: Digital image, bone metastases, osteolytic, optimum cut off point ABSTRAKLatar belakang: Pemeriksaan radiograf tulang secara visual menggunakan sistem radiografi digital CR (computed radiography) merupakan pemeriksaan untuk diagnosis kanker metastasis tulang. Subyektivitas interpretasi radiograf tulang dapat menyebabkan keraguan dokter dalam mengambil keputusan untuk pengobatan pasien dengan kanker tulang metastatik. Software berbasis program aplikasi computer Matlab membuat suatu metode standard untuk mengorganisasikan hasil radiograf tulang. Tujuan penelitianadalah mengembangkan software berbasis Matlab untuk menganalisis nilai-nilai diagnostik, cut off point optimal dan akurasi pemeriksaan pada diagnosis tulang osteolitik.Metode: Data penelitian diambil di bagian radiologi dari tiga rumah sakit, yaitu RSUP Dr. Kariadi Semarang, RSUP Dr. Sardjito dan Rumah Sakit Bethesda Yogyakarta. Penelitian dilakukan selama empat bulan dari April sampai Agustus 2009. Radiograf tulang  osteolitik yang diinterpretasikan oleh radiolog ini dibandingkan dengan hasil pemeriksaan PA tulang osteolitik yang dianggap sebagai gold standard. Langkah yang dilakukan dalam penelitian ini adalah pasien diklasifikasikan sebagai pasien tulang normal dan pasien osteolitik berdasar cut off point yang telah ditetapkan, menghitung nilai uji diagnostik menggunakan tabel 2x2, menghitung luasan di bawah kurva (AUC) dengan cara receiver operating characteristic (ROC), serta menetapkan cut off point optimal.Hasil: Hasil penelitian menunjukkan bahwa uji diagnostik tulang osteolitik menggunakan software berbasis Matlab memiliki sensitivitas 0,875, spesifisitas 0,891, nilai dugapositif 0,897, nilai duga negatif 0,950 dan cut off point 0,93. Nilai luasan di bawah kurva (AUC) ROC adalah sebesar 94%

PENINGKATAN EMISI HIDROGEN MELALUI ATOM HELIUM METASTABIL DENGAN METODE LASER INDUCED PLASMA PADA SAMPEL ZIRCALOY

JURNAL SAINS DAN MATEMATIKA Volume 17 Issue 2 Year 2009
Publisher : JURNAL SAINS DAN MATEMATIKA

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Abstract

ABSTRACT-Telah dilakukan  analisis  unsur  hidrogen  dari sampel  zircoloy  dan  sampel  batu  hitam melalui  pembangkitan  plasma  gelombang  kejut menggunakan laser Nd YAG (1064 nm, 8 ns, 68 mJ)  pada tekanan  rendah  dengan  mengalirkan  gas helium dan gas nitrogen sebagai  gas penyangga  di  dalam  ruang sampel.  Penelitian  dilakukan  untuk menunjukkan  pengaruh  atom  helium metastabil  pada  peningkatan  emisi hidrogen. Pengaruh atom  helium  metastabil pada  peningkatan emisi  hidrogen  ditunjukkan  dengan membandingkan  penggrmaan  gas  nitrogen  dan  gas  helium sebagai  gas  penyangga  pada  tekanan  2 torr dan  5 torr. Dari penelitian,  intensitas  emisi  hidrogen  menggunakan  gas  nitrogen  pada  tekanan  2 torr dan  gas  helium pada  5  torr untuk  sampel  zircaloy masing-masing  diperoleh  sebesar  317,0  cacah/detik  dan  4370,0  cacah/detik, sedangkan  pada  sampel  batu  hitam masing-masing  diperoleh  sebesar  297,6 cacah/detik  dan 694,0 cacah/detik. Hasil  ini  menunjukkan  atom helium metastabil  yang dihasilkan melalui helium sebagai  gas penyangga berpengaruh  terhadap  peningkatan  emisi  hidrogen  pada  sampel  zircaloy dan  batu  hitam. Kata  kunci : sampel zircaloy, sampel batu hitam, laser induced plasma, atom helium metastabil,  emisi hidrogen dan emisi helium.

Pengamatan Efek Magnetooptis Menggunakan Interferometer

JURNAL SAINS DAN MATEMATIKA Volume 14 issue 4 Year 2006
Publisher : JURNAL SAINS DAN MATEMATIKA

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Abstract

ABSTRACT---The magnetooptic effect of transparency material such as aquarium glass, acrylic, and micro slide has been studied using Michelson Interferometer. The change of refractive index to magnetic field B is obtained by placement of samples in a coil applied on altered field 0-0,2 T. Results of interferometer test show that change of refractive index is linearly dependent on B for acrylic and slide. However, for aquarium glass, it is on B2 dependency. This result is agreement to previous experiment that the structure of acrylic and slide is formed more regular as B applied. Keywords: Magnetooptic effect, refraction index, interferometer

PENENTUAN QUALITY CONTROL (QC) RESOLUSI SPASIAL PADA CITRA CT SCAN DENGAN METODE LINE SPREAD FUNCTION (LSF) DAN POINT SPREAD FUNCTION (PSF) MENGGUNAKAN PHANTOM AAPM CT PERFORMANCE

BERKALA FISIKA 2014: Berkala Fisika Vol. 17 No. 2 Tahun 2014
Publisher : BERKALA FISIKA

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Abstract

Computed Tomography (CT scan) is one of the X-ray modalities used in radiodiagnostic, as result it needs to do Quality Control (QC). This study focused on the image quality test of CT Scan by considering the spatial resolution parameters and using calculation method of the digital image. The effect of exposure factors (voltage and electric current) was also on image quality. This study using multislice CT (MSCT) 128 slice and AAPM CT Performance Phantom. Phantom scanned with the variation of exposure factors (80, 100, 120 kV and 50, 100, 150, 200, 250, 300, 350, 400, 450, 500 mA). The determination of spatial resolution value derived from the value of Full Width at Half Maximum (FWHM) of the Line Spread Function (LSF) and Point Spread Function (PSF) graphics. Results shown that the higher voltage applied, the smaller value of FWHM which show better image quality. This method is able to detect spatial resolution up to the 5th level (hole diameter 0.75 mm), whereas it is only up to 3rd level (1.25 mm) visually. The image quality in this study has been compared with the rules of West Austr Compliance Testing Protocol 2006, and it is proved that the  image quality is still good, thus the CT Scanner is still feasible to  use. Key words: CT Scan, Spatial Resolution, Line Spread Function, Point Spread Function

STUDI KOMPARASI METODE PERCENTAGE DEPTH DOSE (PDD) DAN TISSUE PHANTOM RATIO (TPR) UNTUK MENENTUKAN INDEK KUALITAS BERKAS ENERGI 6 MV DAN 10 MV PADA PESAWAT LINAC

BERKALA FISIKA 2015: Berkala Fisika Vol. 18 No. 1 Tahun 2015
Publisher : BERKALA FISIKA

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Abstract

Patient dose in the linac determined with source surface distance (SSD) technique using percentage depth dose (PDD) method and source axis distance (SAD) technique using tissue phantom ratio (TPR) method. Beam quality index is the concept of beam penetration in the water which can be quantized so get a measurable constant. In medical accelerator determined index beam quality    using TPR20,10 to do with counting of PDD20,10 or PDD(10)Research has been carried out by comparing the method PDD and TPR to determine index beam quality of  photon energy 6 MV and 10 MV on the linac. Measurements performed on the PDD method SSD 100 cm and TPR on the SAD 100 cm  with standard field 10 cm x 10 cm. PDD and percent TPR pattern is similar to the built-up area, after dmax will be different. The results of  index beam quality TPR20,10 photon energy 6 MV with a relative measurement 0.660416413 and absolute measurement 0.681884058 at 10 MV photon energies obtained relative measurement 0.73752495 and absolute measurement 0.72896543. Calculation TPR20,10 to PDD20,10 and TPR20,10 for PDD (10) of the relative and absolute measurement of the photon energy 6 MV and 10 MV obtained small deviations of less than 1%. Keywords: PDD, TPR, photon and index beam quality.

STUDI PARAMETER REAKTOR BERBAHAN BAKAR UO2 DENGAN MODERATOR H2O DAN PENDINGIN H2O

BERKALA FISIKA 2015: Berkala Fisika Vol. 18 No. 3 Tahun 2015
Publisher : BERKALA FISIKA

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Abstract

Research about study of Pressurized Water Reactor (PWR) parameters using UO2 as fuel materials with moderator of H2O and coolant of H2O for heterogeneous infinite cylinder design  has realized. There is one of design to make nuclear reactor, it is a neutronic design. At neutronic design, first must calculations to determine group constants ( neutron cross section and the multiplication factor). The neutronic equations with one dimensional  transport theory for annulus geometry can be solved with WIMSD5B codes. Numeric method that used was one dimensional homogenization cell methods. To archieve   steady state or reactor, used enrichment of U235 between 2% until 3,2% with variation 0,05%. From the result with cluster methods with 32 groups and 10 regions, steady states of reactor at enrichment of U235 is 2,9% with effective multiplication factor (keff) = 1,006491. Keywords: PWR, reactor parameters, effective multiplication factor (keff), WIMSD5B

STUDY OF ELECTROOPTICS BEHAVIOUR OF NAPHTHALENE AND ANTHRACENE

BERKALA FISIKA 2015: Berkala Fisika Vol. 18 No. 3 Tahun 2015
Publisher : BERKALA FISIKA

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In this paper, we demonstrate electro-optics behaviour of naphthalene and anthracene using change of polarization of sample induced by external electric field. The source of light for polarization was 1 mW-he-ne Laser 633 nm. The induced external Electric field was produced by high DC voltage 0 – 7 kV. The samples were diluted in solutions-form using wash-benzene. The result shows that anthracene has higher polarizability than naphthalene, which is indicated by higher change of polarization in anthracene than naphthalene. The Assumption that potential difference is proportional to the distance between molecules is shown qualitatively by graphs of Van der Waals potential energy or force between molecules. In this case, anthracene has higher level Energy than naphthalene so that it can be used in visible excitation for environmental spectroscopy. Keywords: electro-optics, polarization, naphthalene, anthracene, Van der Waals potential energy 

Studi Metode Spektroskopi Plasma Laser Tekanan Rendah untuk Identifikasi Unsur Tembaga

YOUNGSTER PHYSICS JOURNAL Vol 5, No 4 (2016): Youngster Physics Journal Oktober 2016
Publisher : Jurusan Fisika, Fakultas Sains dan Matematika, Universitas Diponegoro

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Abstract

The study on laser plasma spectroscopy has been conducted in Optoelectronics and Laser Laboratory, Physics Department, Diponegoro University, to identify the copper spectrums in samples of pure copper and copper alloys. In this study, some of the tested parameters are the comparison of ambient pressure, laser energy and types of sample. In comparative study on ambient pressure, the researcher compared the plasma laser and the spectrum that is constructed of pure copper at the pressure of 1 atm and 3 Torr with PFN 85%. The study on varieties of laser energy was conducted with the PFN values used on pure copper sampel which is at 3 Torr condition, between the range of 75%, 80%, 85%, 90% and 95%. In the test on sample types, the samples used are pure copper, commercial copper, brass key (Cu-Zn) and bronze coin (Cu-Al), at the pressur of 3 Torr and PFN 85%.. As the result, the plasma on ambient pressure of 3 Torr were formed bigger than at 1 atm and it has more clear and better colored spectrum. The higher value of laser’s PFN also lead to greater formed plasma. The dominant and consistent spectrums formed are Cu I 521,82 nm, Cu I 515,32 nm, Cu I 510,56 nm and Cu I 406,26 nm. Based on the calculation conducted by using the Boltzmann plot method, the value f plasma’s temperature that has been formed is rangen in value of 9503,37 – 10906,54 Kelvin.

Penentuan Konduktivitas Listrik dan Frekuensi Karakteristik Sel Ragi dengan Memanfaatkan Proses Dielektroforesis

Majalah Ilmiah Biologi BIOSFERA: A Scientific Journal Vol 27, No 1 (2010)
Publisher : Fakultas Biologi | Universitas Jenderal Soedirman

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Abstract

Dielectrophorestic (DEP), a phenomenon where small particles such as yeast cells are manipulated by non-uniform electric fields. The net dielectrophoretic force is proportional to the polarisability of the cell and cause this cell moving toward higher field. By measuring velocity of the cell on the various frequency of the electric field, it can determine the electrical conductivity and the characteristic frequency of the yeast cells. The results showed that the conductivity of the yeast cell was (10,0 ± 0,4)10-9 Sm-1  and the characteristic frequency was 60 kHz.