TOMO-RAY 01 is the 1^st industrial computerized tomograph in Romania, built in 1993 at the Research and Development Institute for Electrical Engineering (RDIEE). It comprises a control and data-acquisition computer, scintillator detector with associated electronics, a radioactive source, source and detector collimators and shielding, and a computer-controlled monitored assembly for translating and rotating the test object. Individual stepper motors drive the turntable and the carriage, and shaft angle encoders continuously monitor their absolute positions. Mechanics characteristics: 3-axes scanner table (linear error <0.02 mm, rotation error <0.03⁰), maximum diameter of object 250 mm, maximum height object 400 mm, maximum weight 50 kg, distance source-detector 1.400 mm. A 30 Ci (1.11 TBq) gamma-ray isotopic source of iridium-192 with a useful penetration length of up to 10 cm of steel is used. For this source, the best results in reconstructing images are obtained by using the 310.5 and 469.1 keV energy lines groups. The source and detector collimators are identical lead cylinders, 120 mm long. The apertures are of cylindrical shape with 0.9 mm diameter, which determines the maximal resolution in the thickness dimension. CT reconstruction is performed on a PC, using the fast and accurate filtered back projection (FBP) algorithm, combined with the convolution filtering method. The equipment can provide the linear attenuation coefficients in the range 0-6 cm^-1 with good accuracy (typically error 3-5%) for both measuring channels. It worked between 1993 and 2001 at RDIEE.

Personal Contributions

• Designed detection and measurement geometry of equipment (all nuclear parts & detection, acquisition and processing system)
  
• Manufactured shield blocks against radiation, all calibration materials
  
• Performed all tests in improving Modulation Transfer Function (MTF) and reconstruction algorithm
  
• Managed all measurements in certifying the equipment - ensuring compliance with quality requirements
  
• Tested, installed and operated the equipment. Researched, wrote, and edited test procedures and user's guide
  
• Developed and implemented advanced algorithms and applications for CT imaging. Authored “The dual-energy CT method with 192Ir radioisotope for determination of local density and effective atomic number”
  
• Pioneered applications of CT imaging in archaeology, geology, forestry, marine research, and airport and custom security (to identify drugs and explosives) in Romania. Analyzed thousands of objects in the benefit of end-users: industrial objects (for factories), archaeological and art objects (archaeology, museums and churches protected by UNESCO), explosive materials and drugs (police and defense departments, airports and customs), polymetallic nodules and sedimentary cores (marine and geological research), health state of trees (environmental agencies).
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  See other links: LabSystems, Accent Pro 2000

Personal Contributions

• Directed as a Project manager the entirely process in designing and manufacturing of RAY-DENSIMAT - meeting requirements of customer
  
• Designed detection and measurement geometry of equipment (all nuclear parts & detection, acquisition and processing system)
  
• Manufactured shield blocks against radiation and calibration materials
• Tested, installed and operated the equipment at customer
  
• Performed all tests in improving the method's accuracy go to top
  
• Provided training and offered technical support for customer in installing, maintaining and repairing instrument and dedicated software
  
• Researched, wrote, and edited test procedures and user's guide
  

• Wavelength range: 340 - 950 nm; Filter wheel: 9 positions (340, 405, 492, 505, 525, 546, 575, 630, 670 nm); Automatic wavelength setting; Spectral bandwidth: 10±2nm
  
• Temperatures range: room temperature or automatic between 25-40 ºC; Thermostatization by Peltier system; Stability ± 0.5ºC
  
• Sample volume: 100 - 5.000 µl; Reading in 18 µl micro flow cell, macro, semi-micro and micro cuvettes or round test tubes (12 mm diameter x 100mm length)
  
• Absorbance range: from 0 to 2.8 Abs. (from 0 to 2.5 Abs. at 340 nm)
  
• Measurement mode: Abs, T%, Kinetic, Fixed Time, End-Point, MultiKinetic; Calibration by factor, single calibrator, calibration curve, and Kinetics by linear regression
  
• Display LCD 320x240 pixels; Bi-directional SEIKO Thermal Printer (this module is optional); Printing speed: 54 mm/sec.; Print paper width: 58 mm or 80 mm
  
• Instrument has Internal Quality Control Program, RS-232 type serial port at rate: max. 19200 bauds; Dimensions / Weight: 410 x 350 x 178 mm / 12.5 kg go to top