Accent Pro 2000 S.R.L. (AP2K)

SINTERED SAMPLES 2D X-RAY HIGH-ACCURACY DENSITY MEASUREMENT (less than 0.5% error)

elena — Thu, 15 Jun 2023 13:01:26 +0000

Category:

Private funded projects

Period:

January, 2024

Coordinator:

Magurele High Tech Cluster

Laboratory equipment high-accuracy density measurements with X-ray source 160 kV, 350W, Flat panel detector, scanning time 60 seconds; Could be implemented in production line with just few seconds per sample scanning time !!!

First 3D tomogram !!! (1994 at ICPE S.A.)

elena — Thu, 24 Nov 2022 14:36:33 +0000

Category:

National funded projects

Period:

November, 2022

Coordinator:

ACCENT PRO 2000 S.R.L. (Dr. Mihai IOVEA)

LASER-DRIVEN GAMMA IMAGING STUDIES AND EXPERIMENTS FOR APPLICATIONS DEVELOPMENT

elena — Thu, 24 Nov 2022 10:21:44 +0000

Category:

National funded projects

Period:

November, 2022 to February, 2023

Coordinator:

ACCENT PRO 2000 S.R.L. (Dr. Mihai IOVEA)

Objectives of proposed experiment:

The scientific and experimental work proposed in this program will finally
allow us to predict and optimize various laser-driven gamma beam imaging
configurations, as a starting tool for further potential development of
stand-alone microfocus gamma ray sources prototype for being used in the
development of medical, scientific and industrial high-energy gamma
microfocus imaging applications.

EXPERIMENTS FLOW DESCRIPTION

The GAMMA IMAGING EXPERIMENTS at ELI
NP was running for three weeks, between 27 January and 10 February, and
with two additional extension days granted, for 13 th and 14 th February.
Most of the first two weeks time have been spent for new main optical setup, probe beam and laser beam microscope
mounting and aligning , for mechanical design of valve and target movement stages, magnet and microscope positioning
stages, for parabola beam blocker stage, target alignment and for doing first preliminary experiments with Argon gas.
- Because the valve continued to create problems, main issue being shots without gas which created a partial damage of a
  laser mirror by returned scatter laser beam, we continue the experiments only with electrons, but a poor image with
  electrons was obtained in this case.
- In the last day of the given three weeks time, have been analysed the valve problem and an algorithm for controlling it
  by watching the interaction chamber vacuum values was developed and the first experiments have revealed first very
  promising results.
- In the last two additional days, for avoiding to make more damages, we decided to move the bremsstrahlung target to
  the Aluminium exit port Flange thinned at 2mm , and to put outside the chamber the electrons deflecting magnet ,
  setup being presented in Figure 1;
- In the last
  day hours have been achieved the experimental gamma imaging data presented in following.
Experiment Parameters

Laser energy on target: 1,7
2.04 J , Argon pressure: 2 bar, Gas valve predelay: 5 ms ; Valve open time: 10 ms , Laser beam valve height: 1.5 mm;
Laser beam focal size (FWHM): 24 microns, Laser pulse duration: around 30 fs;

GAMMA IMAGING EXPERIMENTS PARTICIPANTS

IFIN HH/ ELI NP Team

Ovidiu TESILEANU / CoPI
Liviu NEAGU CoPI
Yoshihide NAKAMIYA
Georgiana GIUBEGA
Florin NEGOITA
Gabriel COJOCARU
Andrei BERCEANU
Jianfuh
ONG
Petru
GHENUCHE
Madalin
ROSU
Catalin CHIOCHIU
Bogdan
TATULEA
Iani
MITU
Laser Group members

AccentPro2000 S.R.L. (AP2K)

Team
Mihai
IOVEA / PI
Marian NEAGU
Edward Hermann
Mihaela POTERASU
Monica MIREA
External collaborators
Gabriel SULIMAN ( Politehnica Univ & ELI NP)
Laura NITA (PhD student
Politehnica Univ )
GAMMA IMAGING EXPERIMENTS

CONCLUSIONS
- Definitely the three
  weeks granted beam time was totally insufficient for completing such complex experiments.
- We have learned how to look for a stable point of
  gamma imaging experiment, where Laser shots are almost
  continuously good shots, based on the probe beam optimum acceleration channel image, interaction chamber
  vacuum variation on valve shots, EMP induced signal level and watching the Laser parameters.
- The Argon gas is more suitable for the “gamma imaging applications” and low gas pressures data looks more stable.
- The gas valve malfunctions created most of the experiments issues and should be further upgraded or replaced.
- Despite the problems encountered, the
  final day hours gamma imaging experiments show promising results, an
  experiment continuation being necessary;
- Main gamma imaging issues remained the
  gamma beam divergence and pointing variations that reached roughly up
  to 35 % of the field of view size, and a special further investigations for compensating these drawbacks are mandatory
  for the future of this set up imaging capability.
- The Gamma emission during our experiments still was under optimum, being room for more experimental
  improvements.
FUTURE DEVELOPMENT
- We intend to continue our experiment by requesting a new beamtime for focusing on key mechanism of accelerating electrons by
  las er gas
  interactions for our specific needs: relatively low energy range useful electrons (up to 10 20 MeV) for producing useful gamma ray spectrum up to
  5 6 MeV. This requirement is due to the photon energies bigger than 5 6 MeV that are depositing negligible energy in thin standa rd scintillator
  (typically 0.3 1 mm) that is currently used for gamma high resolution imaging.
- We will focus on finding the experiment parameters where are obtained stable shots imaging results, where Laser successive sh
  ots are almost
  similar in terms on intensities, beam size and centroid positions, even if in this case we are not reaching the maximum inten sit ies of electrons or
  photons .
- We will further improve the
  use of the instruments for characterizing the interactions, by optimizing the probe beam visualization of the
  acceleration channel, computing the plasma electrons density with Phasics device, introducing a probe set up for an electro optical crystal for
  calculating the shot electrons bunch duration, improving the valve functionality and monitoring its behavior, monitoring the EMP induced signal
  level, watching the Laser parameters (power, near field intensity shape, spectrum) stability and corelating their values with th e quality of gamma
  imaging
- An improved mechanical design of gas valve and target moving stages will reduce many of the issues encountered;
- Developing a gamma imaging set
  up and a dedicated software capable to analyze in real time each shot imaging by computing the image number
  of photons, field of view dimensions, average energy of incident gamma beam, pointing positions and showing continuously thei r v ariations from
  successive shots.
- We
  intend to extend our applications investigation, from actual gamma imaging goals in in Since and industrial Non destructive Testing,
- to
  acquiring gamma movies of objects in continuous movement/rotation by synchronizing the laser shots with the scanned object position
  and
- by analyzing the
  ultrashort gamma irradiation effect on bio samples, for studies regarding the effects of ultra short Gamma Ray shots in
  imaging techniques, where two specialized bio scientific groups will be partnering

Partners list:

ACCENT PRO 2000 S.R.L. (Dr. Mihai IOVEA) (Romania)

ELI-NP (Romania)

Institutul National de Cercetare-Dezvoltare pentru Fizica si Inginerie Nucleara Horia Hulubei (Romania)

X-CAP Automatic Digital X-Ray Radiography System For Inspection of Small Parts

elena — Thu, 10 Dec 2020 10:41:27 +0000

Category:

Private funded projects

Period:

April, 2020 to April, 2023

Coordinator:

ACCENT PRO 2000 S.R.L. (Dr. Mihai IOVEA)

X-CAP project’s goal is the design and implementation of a complex installation of non-destructive high-resolution X-ray automated inspection, intended for installation in factories production lines of drug capsules, blisters and other plastic, organic or thin metalic small parts.
The samples are scanned using a low energy X-Ray source and a high resolution (60 microns) Time Delay Integration (TDI) detection system.
A software application, based on Machine Learning (ML) technologies that performs dimension measurements and fast detection of defects, is used for analyzing the resulting data.

Program: New advanced technologies for surfaces deposition by using high-power lasers for increasing the materials reliability and performances - PRELAM

elena — Tue, 07 Jan 2020 13:14:36 +0000

Category:

National funded projects

Period:

July, 2019 to July, 2022

Coordinator:

ACCENT PRO 2000 S.R.L. (Dr. Mihai IOVEA)

Our project goal: Laser-based cladding process monitoring by real-time X-ray imaging system.

Category: National funded projects: Competitiveness Operational Program 2014-2020, Priority Axis 1 - Research, technological development and innovation in support of economic competitiveness and business development, Action 1.2.3: Knowledge Transfer Partnerships.

Program manager:Prof. Dr. Ion N. Mihailescu
Project Coordinator: ACCENT PRO 2000 S.R.L.
Contract number: 3/26.07.2019
Project Manager: Dr.Ing.fiz. Mihai IOVEA;
e-mail: office@accent.ro

Valoarea totală a contractului este de 1.210.166 lei. Valoarea totală eligibilă a contractului este 1.190.041 lei, din care 1.022.491 lei reprezintă valoarea totală eligibilă nerambursabilă și167.550 lei reprezintă valoarea cofinanțării eligibile a întreprinderii.
Contractul est eanexă la Contractul de finanțare nr. 135/23.09.2016, afferent cererii de finanțare „Noitehnologii avansate de acoperire a suprafețelor folosind fascicul laser de mare putere în vederea creșterii fiabilității și a performanțelo rmaterialelor - PRELAM”, nr. P_40_412, cod MySMIS: 106093. Proiectul este cofinanțat din FONDUL EUROPEAN DE DEZVOLTARE REGIONALĂ prin PROGRAMUL OPERAȚIONAL COMPETITIVITATE 2014-2020, Axa Prioritară 1 – Cercetare, dezvoltare tehnologică şi inovare (CDI) în sprijinul competitivităţii economice şi dezvoltării afacerilor, Acțiunea 1.2.3, Tip proiect – Parteneriate pentru transfer de cunoştinţe.
Domeniul de încadrare al proiectuluieste „4. ECO-NANO-TEHNOLOGII ȘI MATERIALE AVANSATE", cu focalizare pe subdomeniul „4.4. Materiale. 4.4.1 Substituția materialelor critice și creșterea duratei de funcționare a materialelor prin acoperiri funcționale ”

X-Shaper dedicated non-destructive equipment for ballistic plates in-line control

elena — Fri, 07 Sep 2018 12:59:09 +0000

Category:

Private funded projects

Period:

February, 2018 to August, 2019

X-Shaper Laser & X-Ray Scanner produced by Accent Pro 2000 is designed for ballistic plates in-line control by scanning them in two stages: laser scan and x-ray scan.

The analyzed object is transported by conveyors through a laser beam scanning system, the image being taken over by dedicated video cameras, and after it is scanned using a system that includes an X-ray generator and detectors suitable for this purpose.

Data obtained in this way is processed and analyzed using software applications, obtaining information about size, density and internal structure, allowing automanic identification of possible manufacturing defects.

X-Shaper Laser Scan system consists of 2 surface scanners assemblies, each one using of a linear laser beam and a high definition camera.
The assemblies are posted symmetrically, one on below the scanned object and one under the scanned object.
The data analyze software provides accurate measurements of the product parameters: local thickness, length, width, volume and density.

Max length	500mm
Max width	400mm
Scan duration	10 sec
Thickness rezolution	60 microns
Average density precision	1%

The X-Ray Scan system uses a system of 2 X-Ray high definition detectors, each one providing data regarding different zones of the scanned object.
The application performs complex data processing for enhancing images and automatic detection and measurement of defects inside the object.

X-ray source	AION 160kV X-Ray generator
Focal spot	1,2 mm
Total filtration	0,852 mm Al
Scan duration	20 sec

Partners list:

NUROL Teknoloji A.S. (Turkey)

Elitomo Project: 2D &3D Tomography for Large-size Objects Using ELI-NP Ultrabright Gamma Beam Source

elena — Mon, 25 Sep 2017 07:45:49 +0000

Category:

National funded projects

Period:

September, 2016 to August, 2019

Numar contract: 10ELI / 01.09.2016

Manager proiect: Mihai IOVEA; e-mail: office@accent.ro

Valoare buget: 1.111.200 (1105348.49) RON

Parteneri: P1 Institutul National de Cercetare Dezvoltare pentru Fizica si Inginerie Nucleara "Horia Hulubei"(IFIN-HH) -Romania

Persoane de contact:
Iovea Mihai - Cercetator stiintific, ACCENT PRO 2000, office@accent.ro
Calin Alexandru Ur - Cercetator stiintific I, ELI-NP , calin.ur@eli-np.ro
Violeta Iancu - Cercetator stiintific ELI–NP, violeta.iancu@eli-np.ro

1. REZUMATUL PROIECTULUI

In multe dintre realizarile in stiinta si inginerie ale ultimilor decenii s-au aplicat metode de testare nedistructiva (NDT), folosite in etapa de dezvoltare, fara a distruge sau afecta proprietatile produsului, asigurand integritatea si performantele si pentru care era destinat.
Dintre toate aceste metode, radiografia clasica a inregistrat recent o imbunatatire spectaculoasa, multumita dezvoltarii surselor de raze X Microfocus si detectorilor de raze X de foarte inalta rezolutie.
O consecinta a acestei dezvoltari a fost dezvoltarea a doua noi subdomenii: Radiografia digitala(DR) si Tomografia computerizata industriala(ICT), care au luat avant, devenind cele mai avansate tehnici care pot oferi penetrabilitate sporita si rezolutie spatiala foarte inalta.
Cu toate aceste dezvoltari, inca nu exista solutii NDT satisfacatoare, care sa ofere rezolutie inalta la investigarea componentelor metalice de mari dimensiuni, necesare in diverse domenii, cum ar fi industria aeronautica, industria aerospatiala, industria militara, blocuri si cutii de viteze pentru masini / camioane, piese de rafinare a petrolului etc.
Solutiile utilizate in prezent implica utilizarea unor surse de radiatie de energii inalte, in intervalul 1-15 MeV (cum ar fi Linacs), sau utilizarea unor surse izotropice (de ex.Co60).
Dezavantajul acestor solutii este pata focala mare, cu valori intre 0.5 si 2 mm [1], care reduce dramatic rezolutia spatiala, facand aceste solutii inutile pentru aplicatii de inalta rezolutie.
Dintre toate tehnicile disponibile pentru producerea de fotoni cu energii inalte si pata focala mica, un interes deosebit il reprezinta tehnica Imprastierii Compton a Radiatiei Laser (LCS) [2], care ar putea satisface toate cerintele.
Din acest motiv care noi am propus in ELI White Book [3] dezvoltarea unor aplicatii de radiografie digitala si tomografie, utilizand fascicolul ELI Gamma beam, ca solutie perfecta pentru investigarea DR si ICT de inalta rezolutie a obiectelor de mari dimensiuni.
Sunt notabile principalele avantaje ale utilizarii sursei ELI Gamma beam in DR si ICT:

Este singura solutie disponibila care ar putea oferi o dimensiune focala mica (10-30 microni), oferind imagini cu rezolutie foarte inalta NDT, chiar si pentru obiecte de dimensiuni foarte mari, care sunt usor de penetrat de fotonii cu energie cu energie inalta.
Folosind fotoni peste cativa MeV, rezultatele sunt aproape neafectate de efectul de intarire a spectrului de frecvente si de artefactele de tip striat metalic, intalnite in tehnicile clasice bremsstrahlung DR si ICT.
Avand un fascicul gamma monocromatic reglabil, putem masura valoarea exacta a coeficientului de atenuare liniara a esantionului, iar facand aceleasi masuratori la energii diferite, ar putea fi aplicata o tehnica dual / multienergie pentru identificarea cu precizie a probelor.

La ELI-NP ne asteptam sa obtinem o rezolutie spatiala mai buna (100-200 microni) si o sensibilitate mai mare la contrast in aplicatiile industriale, deoarece intensitatea fascicolului gamma ELI-NP va fi cu cateva ordine de marime mai mare decat la HIγS (SUA) AIST (Japonia).
Trebuie remarcat faptul ca actualii parteneri ELITOMO au realizat pana in prezent la ELI-NP simulari Monte Carlo pentru aplicatiile NDT industriale, stabilind cerintele de baza pentru scanerele mecanice DR si TEC.
In cadrul proiectului propunem construirea a doua masini DR si TIC (pentru probe mici si mari), proiectarea si realizarea de detectoare gamma 1D si 2D gamma dedicate si dezvoltarea pachetelor software pentru achizitia de date, controlul scanerelor, scanarea tomografica speciala, tehnici de reconstructie, algoritmi de imbunatatire a imaginii si vizualizare.
O serie de teste preliminare cu ambele echipamente vor fi facute in laborator utilizand surse de Microfocus de raze X, surse Gamma sau LINAC.
In cele din urma, o serie de teste la CETAL sau la alte unitati LCS vor fi urmate de instalarea sistemului la ELI-NP GAMMA BEAM, fiind pregatite pentru experimente de la DAY ZERO.

2. OBIECTIVELE PROIECTULUI

Proiectul ELITOMO isi propune sa furnizeze suportul necesar pentru dezvoltarea aplicatiilor de imagistica industriala, utilizand sistemul ELI-NP gamma beam.
Obiectivele proiectului sunt:

Studiul impactului si avantajelor utilizarii surselor de raze X si a surselor Gamma (Co-60, Subaru-Japan) ca platforme de testare pentru configuratia experimentala utilizand simulari Monte Carlo.
Dezvoltarea procedurilor speciale de scanare, achizitie digitala si a sistemelor read-out pentru setup-urile experimentale pencil-beam cone-beam. Vor fi dezvoltati algoritmi specifici de reconstructie, vor fi teste pachete software de analiza a imaginilor.
Dezvoltarea detectorilor si realizarea de prototipuri pentru experimentele cu fascicul pencil-beam. Fascicolul gamma de intensitate mare avand o structura temporala specifica, genereaza pulsuri de fotoni de mare intensitate care ajung la detector intr-o fereastra de o picosecunda. Pulsurile de fotoni cu intensitate ridicata vor produce daune in detectoarele conventionale si saturarea PMT-urilor. Propunem un studiu de impact al utilizarii unor scheme de detectie alternative in locul detectorilor conventionali NaI cuplati cu PMT utilizati in mod frecvent in experimentele CT. Cu simulari Monte Carlo propunem sa studiem posibilitatea utilizarii unui calorimetru pentru raze gamma pentru experimentele cu fascicul pencil-beam.
Testarea ambelor scanere si a pachetelor software in diferite medii de laborator cu diferite tipuri de surse: raze X si raze gamma disponibile in mod curent inainte de instalarea la ELI-NP
Formarea si instruirea personalului experimental pentru functionarea viitoare a setarilor experimentale dedicate tomografiei si radiografiei
Furnizarea suportului pentru instalarea si testarea sistemelor DR si TIC la ELI-NP

3. REZUMATUL REZULTATELOR

Pana acum au fost realizate urmatoarele activitati:

Implementrea surselor de fotoni LCS in Geant4 in vederea evaluarii raspunsului detectorilor in conditii similare celor dinexperimentul real (IHIN-HH);
Dezoltatrea a doi algorimi de reconstructie tomografica fan-beam: Filtered Back Projection (FBP) si Algebraic Iterative Reconstruction algorithm (AIR) (AP2K)
Simulari Monte Carlo de proiectii cu structura perechi de linii pentru estimarea rezolutiei spatiale si a sensitivitatii contrastului pentru sistemul ELI-NP gamma beam(IHIN-HH and AP2K)
Testarea pachetului VOLUME GRAPHICS© , un pachet software high-end pentru analiza si vizualizarea datelor in tomografia computerizata(CT) industriala(AP2K)
Analiza a diverse tipuri de scintilatori in vederea optimizarii detectorilor 2D pentru tomografia cu ELI-NP gamma-beam (IHIN-HH)
Instalarea unui cluster de computere capabil sa excute in paralel programe de simulare Monte Carlo, reconstructie tomografica si analiza de imagini(AP2K)
Utilizaea pachetului software VOLUME GRAPHICS© in reconstructii tomografice 2D (AP2K)
Simulari Monte Carlo cu Geant4 pentru sisteme translatii + rotatii utilizate la scanarea obiectelor de dimensiuni mai mari with ELINP Gamma Beam (AP2K)
Realizarea analizei de contrast, a raportului semnal/zgomote (SNR), evaluate pe date simulate cu Geant4 pentru tinte de marimi diferite, din materiale diferite(IFIN-HH and AP2K)
Dezvoltarea detectorului Gamma 2D gamma pentru experimentele cu fasicolul gamma beam (AP2K)
Proiectarea si dezvoltarea procedurii pentru controlul scanarii, procedurii de achizitie de date si integrarea algoritmilor de reconstructie pentru obiecte mari in mediul de laborator pentru fascicolul X-ray fan/pencil beam (AP2K)
Simularea unui calorimetru pentru raze gamma si proiectarea de aplicatii cu tomografie gamma computerizata(IFIN-HH)

4. PREZENTAREA REZULTATELOR STIINTIFICE

4.1 Simularea surselor de fotoni LCS in Geant4 pentru evaluarea raspunsului detectorilor in conditii similare celor dintr-un experiment real (IHIN-HH)

Sursele disponibile LCS pot furniza fascicule gamma cu largimea de banda de cateva procente(e.g. 3% at HIγS) si intensitati of 105 fotoni/s la NewSubaru si 107 fotoni/s la HIγS.
Pentru evaluarea respunsului detectorilorlor in conditii similare celor dintr-un experiment real si compararea performantele setup-urile DR si ICT cu surse diferite
a fost necesar sa implementam cateva din sursele mentionate mai sus in codul de simulare Geant4. Sursele monoenergetice si sursele X-ray/bremsstrahlung au fost implementate utilizand modulul General Particle Source din Geant4,cu distributii Gauss si bremsstrahlung.
Un exemplu de distributie energetica a celor doua tipuri este reprezentat in Figura 1.

Fig.1 Stanga: Distributia energetica bremsstrahlung cu end-point la 3.5 MeV si largimea de banda de 0.5% centerat in 3 MeV. Diferenta dintre intensitatile relative pentru cele doua distributii e arbitrara.
Dreapta: distriibutia energetica pentru LCS gamma beam inainte si dupa colimare cu colimatori de apertururi diferite.

4.2 Simularea raspunsului detectorilor (IFIN-HH)

Geant4 a fost folosit si pentru simulari care sa caracterizeze raspunsul detectorilor la un fascicul cvasi-monoenergetic asa cum va fi Gamma Beam ELI-NP.
Se preconizeaza ca vor fi folosite doaua tipuri de detectori in setup-urile DR si ICT la ELI-NP:

Un detector de volum mare capabil sa absoarba aroape integral radiatia gamma transmisa pentru tomografie computerizata cu fascicul pencil-beam
Un detector 2D pentru tomografie comuterizata cu fascicul conic, constand intr-un ecran convertor(converteste fotonii gamma in fotoni vizibil) cuplat print-un sistem optic cu o camera CCD.

Energia depozitata, eficienta detectorului si raportul peak to total au fost determinate pentru diferite tipuri de detectori si scintilatori diferiti.
Figura 2 ilustreaza raportul peak to total pentru mai multi scintilatori cu volum mare, iar in Tabelul 2 este prezentata energia depozitata pentru diversi scintilatori subtiri.

Fig. 2 Peak to total ratio pentru cativa scintilatori cu volum mare

Scintilator	Grosime (mm)	3.5 MeV	5 MeV	10 MeV	20 MeV
BGO	0.5	4.36x10^-3	8.41x10^-3	8.36x10^-3	9.11x10^-3
BGO	1	1.6x10^-2	3.50x10^-2	3.75x10^-2	3.96x10^-2
BGO	2	5.65x10^-2	0.12	0.16	0.17
LYSO	2	8.01x10^-2	9.81x10^-2	1.22x10^-1	1.36x10^-1
CsI(Tl)	0.5	2.76x10^-3	2.89x10^-3	2.57x10^-3	3.25x10^-3
CsI(Tl)	2	4.11x10^-2	4.64x10^-2	5.57x10^-2	6.11x10^-2
Gadox	0.2	1.05x10^-3	1.0 x10^-3	1.1x10^-3	1.2x10^-3

Tabelul 1
Energia depozitata in MeV per foton incident pentru fotonii care lovesc un scintilator subtire.

4.3. Proiectarea si realizarea unui a cluster de computere pentru executii in paralel a programelor de simulare Monet Carlo si reconstructie

Pentru simulari si programe de reconstructie a fost construit un cluster de calculatoare cu 96 nuclee, compus din 4 unitati , fiecare dispunand de 4 procesoare Intel Xeon X5650 si 16 GB RAM, fiecare ruland sub sistemul de operare CENTOS 7 , cuplate prin MPI CH.
Pentru a profita de avantajele procesarii in paralel in GEANT4, am instalat G4MPI (o interfata nativa cu MPI a librariilor programelor de simulare) si a fost modificat programul de simulare pentru executie in paralel.
Aceasta arhitecutura cu 96 de nuclee a permis executia de simulari Monte Carlo cu 10¹¹ fotoni/proiectie si 100 de proiectii pentru un obiect de 25 cm3 in aproximativ 4 zile.

Fig. 3 Clusterul cu 96 nuclee utilizat in simularile AP2K

4.4. Determinarea rezolutiei spatiale si a Sensisbilitatii contrastului pentru date tomografice simulate (AP2K)

Pentru datele tomografice simulate, am folost configuratia fan-beacu distanta sursa-obiect de 10 m, distanta sursa-detector de 40 m ,dimensiunile detectorilor de 4x4 cm2 detector size, spatiul dintre detectori de 0.1x0.1 mm2, pata focala de 10 µm si divergeta fascicolului de 1 mrad, toate datele simulate la energia gamma beam de 1 MeV.
Obiectele simulate au fost blocuri de fier de 5 si 10 cm constand in (a) cilndri avand in interior gauri cilindrice (umplute cu aer) de dimensiuni diferite (fig. 4a),blocuri din fier cu gauri sferice de dimensiuni diferite (fig. 4b), (c)respectiv trepte din fier de grosimi diferite continand cilindri cu aer (fig.4c).

Fig. 4 Obiecte simulate: A- cilindru din fier cu gauri cilindrice, B- bloc din fier cu gauri sferice, C- trepte din fier cu gauri cilindrice.

Fig. 5 Bloc metalic cu gauri sferice. A - obiect simulat, B - projectia simulata pentru un bloc de 10cm din fier cu 10¹⁰ fotoni incidenti, C - projectia simulata pentru un bloc de 5 cm din fier block cu 10¹⁰ fotoni incidenti, D -projectia simulata pentru un bloc de 5 cm din fier cu 10¹¹ fotoni incidenti.

Fig. 7 Variatia raportului semnal/zgomot (SNR) in functie de diametrul gaurii (stanga) si functia de transfer a modulatiei (MTF) (dreapta) pentru simulari Geant4 cu trepte din fier cu gauri cilindriice (Fig6 C).

4.5. Reconstructia Tomografica (AP2K)

Pentru reconstructie s-au folostit algoritmii Filtered Back Projection si algoritmul iterativ SART cu numar diferit de proiectii. Pentru algoritmul Filtered back projection
[8] s-au folosit pachetele software IRTm [11] si Volume Graphics Studio Max[13,14,15].Pachetul AIR [12] a fost folosit pentru reconstructia iterativa [9,10].
Unul din obiective a fost determinarea numarului minim de proiectii si determinarea timpului necesar de integrare al detectprilor pentru atingerea unei rzolutii spatiale de cel putin 200 de microni.
Concluzia studiului a fost ca, pentru un fascicul gamma de 1 MeV cu intensitatea de 2.5*107 fotoni incidenti/mrad, o imagine de calitate rezonabila (in care cilindrii cu diametrul de 200 microni pot fi distinsi in mod clar) poate fi obtinuta intr-un un timp de integrare de minimum 1 secunda/proiectie cu minimum 100 de proiectii distribuite in mod egal.

Intensitate	Nr. proiectii	Rezolutie
`2.5*10⁷` `Fotoni incidenti /slice/1mrad`	33	0.6 mm
	66	0.4 mm
	100	0.2 mm

Fig. 8
Imagini reconstruite utilizand 33, 66, 100 proiectii cu algoritmii Filtered Back Projections si SART.

Fig. 9
Analiza imaginii cu Volume Graphics.

4.6. Dezvoltarea detectorului 2D gamma pentru experimentele cu fasicolul gamma beam. (AP2K)

Pulsurile de fotoni de inalata intensitatea vor produce daune si in detectoarele conventionale si saturarea PMT-urilor.Am construit un detector gamma 2D utilizand un strat de scintilator, o oglinda si o camera CCD, montate intr-o camera obscura , prezentat in Figura 10.

Fig.10
Detectorul gamma 2D.

4.7. Dezvoltarea de noi algorimi iterativi de reconstructie 3D (AP2K - in curs de dezvoltare)

Pentru diminuarea timpului de scanare necesar pentru FBP (cand sunt necesare minimum 100 proiectii pentru o rezolutie de 200 de microni) investigam in continuare posibilitatea aplicarii algoritmului de reconstructie iterativ cu un numar redus de proiectii.

Fig.11
Aplicatie software pentru reconstructii tomografice, simulari de date, reconstructii iterative si vizualizari 3D pentru ELINP Gama Beam.

4.8. Realizarea unui calorimetru gamma pentru aplicatii de tomografie computerizata(IFIN-HH n curs de dezvoltare)

Studiem optiuniea de a utiliza un calorimetru gamma pentru caracterizarea fasciculului transmis in experimente CT pornind de la o versiune simplificata prezentata in referinta [17].
Prototipul calorimetrului va utiliza mai multe straturi de detector de polietilena (PE) - Si, distantat de absorbantii PE mai mari (figura 12a).
Fiecare strat este format din 3 cm PE care precede un detector Si. Patru blocuri PE mai mari de 12,56 cm, 12,56 cm, 15,66 cm și 12,56 cm separa straturile PE-Si.
Figura 3b prezinta rezultatul simularii energiei depuse in functie de energia fasciculului gamma, pentru un dispozitiv cu 5 și 22 de straturi.
Procedura de determinare a energiei fasciculului și a intensitatii fasciculului este similara cu cea descrisa in referinta [18].

Fig.12.
(a)Diagrama a prototipului calorimetrului gamma care va fi folosit pentru experimente CT. (b) Distributia longitudinala a energiei depuse in detectoarele cu Si pentru mai multe energii ale fasciculului gama.

Security Applications: X-Ray Dual/Multi Energy and Diffraction Technique for Single/Dual View Digital Radiography and 2D & 3D Tomography for Baggage Threats detection

elena — Mon, 29 May 2017 12:14:00 +0000

Category:

National funded projects

Period:

January, 2015

Partners list:

ACCENT PRO 2000 S.R.L. (Dr. Mihai IOVEA) ()

Elitomo Project: 2D &3D Tomography for Large-size Objects Using ELI-NP Ultrabright Gamma Beam Source

elena — Tue, 25 Oct 2016 11:42:13 +0000

Category:

National funded projects

Period:

September, 2016 to August, 2019

Contract number: 10ELI / 01.09.2016

Project Manager: Mihai IOVEA; e-mail: office@accent.ro

State Budget value: 11.111.200 (1105348.49) RON

Partners: P1 Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering (IFIN-HH) -Romania

Contact Persons:
Mihai Iovea - Senior research scientist, ACCENT PRO 2000, office@accent.ro
Calin Alexandru Ur - Senior Researcher I, ELI-NP , calin.ur@eli-np.ro
Violeta Iancu - Research Scientist III, ELI–NP, violeta.iancu@eli-np.ro

1. SHORT DESCRIPTION

Many of the important scientific and engineering achievements of the last decades can be traced back to non-destructive testing (NDT) methods that have been used during development stage without damaging or affecting the product properties, hence assuring the performance and integrity for which the product was intended. From all existent NDT methods, the classical radiography has been spectacularly improved lately thanks to the development of the microfocus X-ray sources and of very high-resolution X-ray detectors. As a result, two new improved sub-domains called Digital Radiography (DR) and Industrial Computed Tomography (ICT) have been developed and became the most advanced techniques that could offer high-penetrability at very high spatial resolution. Despite the latest improvements there is still a lack of high-resolution NDT solutions for investigating large size metallic components, such as aeronautics, space and military products, cars/trucks engine blocks and gearbox, oil refinery parts, etc. The industrial solutions available are based on using high-energy radiation sources in the range of 1-15 MeV (such as Linacs) or isotopic sources (Co60, for example). But these solutions deliver a very big focal spot size in the range of 0.5 – 2 mm [1], which reduces dramatically the spatial resolution and are practically not useful in the high-resolution applications. From all other techniques available for producing high-energy photons with small focal spot, the Laser Compton Scattering is of very much interest [2] that could meet all the requirements. This is the reason why we have proposed in the ELI White Book [3] to develop the digital radiography and tomography applications by using ELI Gamma beam, as a perfect solution for high-resolution DR and ICT investigation of large-size objects. It is noteworthy to mention the main advantages of using ELI Gamma Beam source in DR and ICT for industrial large-size objects for NDT applications. (i) It is the only solution available that could provide small focal spot size (10-30 microns) providing very high-resolution NDT imaging even for very large-size objects that are easily penetrated by the high-energy beam; (ii) By using photons over a few MeV the results are almost free from beam hardening effect and the metal streak artifacts usual found in classical bremsstrahlung DR and ICT techniques. (iii) By having a tunable monochromatic gamma beam we can measure the sample’s exact values of the linear attenuation coefficient and, by doing same measurement at different gamma energies, a dual/multi energy technique could be applied for material identification. At ELI-NP we expect to achieve unprecedented spatial resolution (100-200 microns) and contrast sensitivity in industrial applications since the intensity of the ELI-NP gamma beam will be few orders of magnitude higher than at HIγS (USA) or at AIST (Japan). Up to now, the ELITOMO partners have developed the Monte Carlo simulation for industrial NDT applications and established the basic requirements for the DR and ICT mechanical scanners. Within this project we propose to design and develop detection systems and to develop the dedicated scanning control procedure and the digital acquisition and read-out system for these DR and ICT setups before installation at ELI-NP. In addition, a series of preliminary tests and experiments will be made in laboratory by using X-Ray microfocus sources, gamma sources or LINAC. Finally a series of tests at CETAL or other LCS facilities will be followed by the installation of the two systems at ELI-NP GAMMA BEAM facility.

2. PROJECT OBJECTIVES

The ELITOMO project aims at providing support for industrial imaging applications development at ELI-NP gamma beam system. The project objectives are:

Study the impact and the advantages of using X-ray sources (AP2K) and currently available gamma sources (Co-60, Subaru-Japan) as test beds for the experimental configurations using Monte Carlo simulations
Develop dedicated scanning control procedure and digital acquisition and read-out system for pencil-beam and cone-beam tomography setups. Specific tomographic reconstruction algorithms will be developed and image analysis software packages will be tested.
Detector development and prototyping for pencil beam experiments. The high intensity of the gamma beam and the peculiar gamma beam time structure yield high intensity photon pulses that arrive at the detector in a picosecond window. The high intensity photon pulses will create radiation damage in the conventional detectors and saturation of the PMTs. We propose to study the impact of using alternative detection schemes to the conventional NaI detectors coupled with PMT that are often used in the CT experiments. Using Monte Carlo simulations we propose to study the possibility to use a gamma-ray calorimeter for the pencil-beam experiments.
Test both scanners and software packages in various laboratory environments with different type of sources: X-rays and currently available gamma ray sources before installation at ELI-NP
Formation and training of experimental personnel for future operation of the experimental setups dedicated for tomography and radiography
Offer support for installation and tests of both DR and ICT systems at ELI-NP

3. SUMMARY OF RESULTS

The performed activities up to now are:

Implementation of LCS photon sources in Geant4 for assessing the response of the detectors in conditions like those in a real experiment (IHIN-HH);
Development of two fan-beam tomographic reconstruction algorithms: Filtered Back Projection (FBP) and Algebraic Iterative Reconstruction algorithm (AIR) (AP2K)
Monte Carlo simulations of line-pair structures projections for estimating the spatial resolution and contrast sensitivity for ELI-NP gamma beam environment (IHIN-HH and AP2K)
Testing of the VOLUME GRAPHICS© software, a high-end software package for analysis and visualization of industrial computed tomography (CT) data (AP2K)
Scintillators type analysis for optimization of the 2D detector for ELI-NP gamma-beam tomography (IHIN-HH)
Setting up a cluster computer capable to perform parallel computing for Monte Carlo simulations, tomographic reconstruction and image analysis (AP2K)
Monte Carlo simulations with Geant4 for translation + rotation system for scanning larger dimension objects with ELINP Gamma Beam (AP2K)
Performing contrast analysis, signal to noise (SNR) evaluation on Geant4 simulated data for targets of different materials and sizes (IFIN-HH and AP2K)
2D gamma detector development for gamma beam experiments (AP2K)
Design and development of the scanning control procedure, data acquisition, data reconstruction algorithm integration for large objects in X-ray fan/pencil beam laboratory environment (AP2K)
A gamma-ray calorimeter simulation and design for computed tomography gamma applications (IFIN-HH)

4. SCIENTIFIC RESULTS PRESENTATION

4.1 Simulations of LCS photon sources in Geant4 for assessing the response of the detectors in conditions like those in a real experiment (IHIN-HH)

The available LCS sources can provide gamma beams with several percent bandwidths (e.g. 3% at HIγS) and intensities of 105 photons/s at NewSubaru and 107 photons/s at HIγS. To assess the detector responses in conditions similar to the real experiments and to compare the performance of the DR and ICT setups with different sources we have implemented some of the above-mentioned gamma sources in our Geant4 simulation code. The monoenergetic sources and the X-ray/bremsstrahlung sources are implemented using the General Particle Source toolkit in Geant4, using the Gaussian and the bremsstrahlung distributions. An example of energy distributions for these two types of sources is displayed in figure 1.

Fig.1 Left panel: the energy distribution of 3.5 MeV end-point bremsstrahlung distribution and a 0.5% bandwidth distribution centered at 3 MeV.
The relative intensity difference between the two distributions is arbitrary. Right panel: the energy distribution of an LCS gamma beam before and after collimation with various apertures collimators

4.2 Detector Response Simulations (IFIN-HH)

Geant4 simulations were also used to characterize the response of detectors to quasi-monoenergetic beams like the future gamma beam from ELI-NP.
Two types of detectors are foreseen to be used for gamma beam DR and ICT setups at ELI-NP: (i) a large volume detector capable of absorbing almost entirely the transmitted
gamma beam for pencil-beam CT, and (ii) a 2D detector for cone-beam CT consisting of a converter screen (converts gamma rays to visible photons) coupled via optic elements to a CCD camera. The deposited energies, the detector efficiencies, as well as the peak-to-
ratio were determined for different types and sizes of scintillators.
Figure 2 shows the peak to total ratio of a large volume scintillator and Table 2 lists the deposited energy in various thin scintillators

Fig. 2 Peak to total ratio for several large volume scintillators

Scintillator	Width (mm)	3.5 MeV	5 MeV	10 MeV	20 MeV
BGO	0.5	4.36x10^-3	8.41x10^-3	8.36x10^-3	9.11x10^-3
BGO	1	1.6x10^-2	3.50x10^-2	3.75x10^-2	3.96x10^-2
BGO	2	5.65x10^-2	0.12	0.16	0.17
LYSO	2	8.01x10^-2	9.81x10^-2	1.22x10^-1	1.36x10^-1
CsI(Tl)	0.5	2.76x10^-3	2.89x10^-3	2.57x10^-3	3.25x10^-3
CsI(Tl)	2	4.11x10^-2	4.64x10^-2	5.57x10^-2	6.11x10^-2
Gadox	0.2	1.05x10^-3	1.0 x10^-3	1.1x10^-3	1.2x10^-3

Table 1 Deposited energy in MeV per incident photon that
strike a thin scintillator panel.

4.3 . Design and manufacturing of a cluster computer for parallel computing in Monte Carlo

For simulation and data reconstruction processes we have built a 96 cores computing cluster consisting of 4 units, each unit having 4 Intel Xeon X5650 processors and 16 GB RAM, each one running CENTOS 7 operating system coupled via MPI CH. In order take advantage of multiprocessing in GEANT4 we installed G4MPI (a native interface with MPI libraries simulation programs) and adjust the simulation program for parallel computing. This 96 cores architecture allowed to perform a Monte Carlo simulation of 1011 photons/projection and 100 projections, for an object having25 cm3, in about 4 days.

Fig. 3 96cores cluster computer used in AP2K simulations

4.4. Determination of Spatial Resolution and Contrast Sensitivity for Reconstructed Simulated Tomographic Data (AP2K)

For the tomographic data simulation, we used a fan beam set-up having 10m source-object distance, 40 m source-detector distance, 4x4 cm2 detector size, detector pitch of 0.1x0.1 mm2, the beam focal spot size of 10 µm and beam divergence of 1 mrad, all data simulated for 1 MeV gamma beam energy. The simulated objects were a 5 and 10 cm iron block having inside (a) iron cylinders containing cylindrical holes (air filled) of different sizes (fig. 4a), iron block containing spherical air holes (fig. 4b), respectively iron steps of different width containing cylindrical air holes (fig.4c).

Fig. 4 Simulated targets: A- iron cylinder with cylindrical holes, B-iron block with spherical holes, C- iron steps with cylindrical air holes.

Fig. 5 Metal block with spherical air holes. A - simulated spheres, B -simulated projection for 10cm Iron block with 10¹⁰ incident photons, C - simulated projection for 5 cm iron block with 10¹⁰ incident photons, D -simulated projection for 5 cm iron block with 10¹¹ incident photons.

Fig. 7 Variation of the signal to noise ratio with hole diameter (left) and the Modulation Transfer Function (left) for Geant4 simulation of iron steps with cylindrical air holes (Fig6 C).

4.5. Tomographic Reconstruction (AP2K)

The algorithms used in reconstruction were the Filtered Back Projection and the iterative SART algorithm for different number of projections. For Filtered back projection algorithm [8] the IRTm package [11] and Volume Graphics Studio Max. package [13,14,15] were used, while the AIR [12] toolkit was used for iterative reconstruction [9,10]. One of the targets was to determine the minimum number of projection and the detector integration time necessary for achieving at least 200 microns spatial resolution. We determined that, for 1 MeV gamma intensity of 2.5*107 incident photons/mrad, a reasonable image quality (where the 200 microns cylinders are clearly separated) could be obtained for a minimum of 1 second integration time for one projection and for a minimum of 100 equal-distributed projections acquired.

Intensity	No. of projections	Resolution limit
`2.5*10⁷` `Incident photons /slice/1mrad`	33	0.6 mm
	66	0.4 mm
	100	0.2 mm

Fig. 8
Reconstructed images using 33, 66,100 projections with Filtered Back Projections and SART algorithms.

Fig. 9
Image analysis with Volume Graphics.

4.6. 2D gamma detector development for gamma beam experiments. (AP2K)

The high intensity photon pulses will create radiation damage and saturation in the conventional detectors. We built a 2D gamma detector by using a scintillator sheet, a mirror and a CCD camera mounted in a dark room frame presented in Figure

Fig.10
Two-dimensional gamma ray detector.

4.7. New iterative 3D reconstruction algorithm development (AP2K - under development)

For reducing the scanning time required by the FBP scanning algorithm (when a minimum 100 projections are necessary for having around 200 microns resolution) we are further investigating the results of applying iterative reconstruction algorithm with a reduced number of projection.

Fig.11
Computer application for tomographic data simulation, iterative reconstruction and visualizations for ELINP Gama Beam.For reducing the scanning time required by the FBP scanning algorithm (when a minimum 100 projections are necessary for having around 200 microns resolution) we are further investigating the results of applying iterative reconstruction algorithm with a reduced number of projection.

4.8. A gamma-ray calorimeter for computed tomography applications (IFIN-HH under development)

We are currently studying the option to use a gamma calorimeter for characterizing the transmitted beam in the CT experiments starting from a simplified version presented in reference [17]. The calorimeter prototype will use several layers of polyethylene (PE) – Si detector spaced by larger PE absorbers ( Fig. 12a). Each layer consists of 3 cm PE preceding a Si detector. Four larger PE blocks of 12.56 cm, 12.56 cm, 15.66 cm and 12.56 cm separate the PE-Si layers. Figure 3b shows the simulation result of deposited energy as a function of the energy of the gamma beam for a 5- and 22-layer device. The procedure to determine the beam energy and the beam intensity is similar to the procedure described in reference [18].

Fig.12.
(a) A diagram of a gamma calorimeter prototype to be used for CT experiments. (b) The longitudinal distribution of the energy deposited in the Si detectors for several energies of the gamma beam.

CIL2018: NextGen Scanner for Checked in Luggage

admin — Mon, 18 Apr 2016 08:23:37 +0000

Category:

European funded projects

Period:

March, 2016 to March, 2019

Better X-ray-screening to improve safety at airports

Partners list:

ACCENT PRO 2000 S.R.L. (Dr. Mihai IOVEA) ()

Dansk Ingeniør Service A/S (Romania)

Exruptive A/S (Denmark)

Innospexion APS (Denmark)

Magnatek ApS (Denmark)

Accent Pro 2000 S.R.L. (AP2K)

SINTERED SAMPLES 2D X-RAY HIGH-ACCURACY DENSITY MEASUREMENT (less than 0.5% error)

First 3D tomogram !!! (1994 at ICPE S.A.)

LASER-DRIVEN GAMMA IMAGING STUDIES AND EXPERIMENTS FOR APPLICATIONS DEVELOPMENT

EXPERIMENTS FLOW DESCRIPTION

Experiment Parameters

GAMMA IMAGING EXPERIMENTS PARTICIPANTS

IFIN HH/ ELI NP Team