Terrestrial laser scanners (TLSs) are 3D imaging systems that provide the most powerful 3D representation and practical solutions for various applications. Hence this is due to effective range measurements, 3D point cloud reliability, and rapid acquisition performance. Stonex X300 TOF scanner delivered better certainty in far-range than in close-range measurements due to the high noise level inherent within the data delivered from Time of Flight (TOF) scanning sensors. However, if these errors are manipulated properly using a valid calibration model, more accurate products can be obtained even from very close-range measurements. Therefore, to fill this gap, this research presents a user-oriented target-based calibration routine to compute the calibration parameters of Stonex X300 TLS. The proposed routine investigates range and angular measurements to mitigate mechanical misalignment error sources of this device. Distance and angular index errors were computed, and environmental error sources were considered for optimal modeling estimation. The approach is based to reference measurements in a close-range environment within a 10-meter distance to user-defined ground truth targets. Experiment results show that the errors in the distance are generally increased following the increase in range distance between the laser device and the targets. However, error variations between laser and reference measurements nearly constant relational to the range value. The index error of the Stonex X300 was computed based on mean measurements and found to be equal to 4.6717 mm. On the other hand, the horizontal angular measurements delivered from the TLS device were found to be more consistent with the reference measurements than with thee vertical angular measurements. However, the vertical angular measurements show more significant variations in particular measures compared to horizontal angular measurements. Following this, the angular error index was computed and found to be equal to 0.07 seconds and 0.13 seconds in horizontal and vertical angular measurements, respectively.
Aluminum plasma was generated by the irradiation of the target
with Nd: YAG laser operated at a wavelength of 1064 nm. The
effect of laser power density and the working pressure on spectral
lines generating by laser ablation, were detected by using optical
spectroscopy. The electron density was measured using the Stark
broadening of aluminum lines and the electron temperature by
Boltzmann plot method it is one of the methods that are used. The
electron temperature Te, electron density ne, plasma frequency
and Debye length increased with increasing the laser peak
power. The electron temperature decrease with increasing gas
pressure.
Background: Dental implants provide a unique treatment modality for the replacement of a lost dentition .This is accomplished by the insertion of relatively an inert material (a biomaterial) into the soft and hard tissue of the jaws, there by providing support and retention for dental prostheses. Low level laser therapy (LLLT) is an effective tool used to prompt bone repair and remodeling, this has referred to the biostimulation effect of LLLT. The Aim of this study was to evaluate the effects of inflammatory cells on osseointegration of CpTi implant irradiated by low level laser. Materials and Methods: thirty two adult New Zealand white rabbits, received titanium implants were inserted in the tibia. The right side is considered as experime
... Show MoreBackground: Corticotomy-assisted orthodontic treatment is done to induce a state of increased tissue turnover and transient osteopenia, which is followed by a faster rate of orthodontic tooth movement. It considered as an adjunct treatment option for orthodontic treatment of adults. The aim of this Study was to elucidate the effectiveness of a new surgical approach for acceleration of maxillary canine retraction in human with laser assisted flapless corticotomy and evaluate its effect on vitality of pulp and gingival sulcus depth. Materials and methods: the sample comprised of 15 Iraqi patients (9 females and 6 males; mean age 21.7), who were required extraction for their maxillary first premolars followed by retraction of the canines as pa
... Show Moreحصاة الحالب واعراضها تؤثر على حياة المريض بصوره سلبيه، عدة علاجات متوفرة لعلاج حصاة الحالب من ضمنها مراقبه المريض، استخدام ادويه تفتيت الحصاة، استخدام موجات الفوق الصوتية تفتيت الحصاة بناظور الحالب، استخراج الحصاة جراحيا او بالناظور البطني, استخدام ناظور الحالب وتفتيت الحصاة بالليزر هي الطريقة المفضلة لعلاج حصاة اسفل الحالب. الهدف من الدراسة:لمقارنه تأثير ومضاعفات استخدام تقنيه الطحن او تقنيه التكسي
... Show MoreDiode lasers are becoming popular in periodontal surgery due to their highly absorption by pigments such as melanin and hemoglobin their weak absorption by water and hydroxyapatite makes them safe to be used around dental hard tissues. Objective: The aim of the present study was to evaluate the efficiency of diode laser in performing gingivectomy in comparison to conventional scalpel technique in patients with chronic inflammatory enlargement. Materials and methods: Thirty patients were selected for this study. All of them required surgical treatment of gingival enlargements and were randomly divided into two groups: Control group (treated by scalpel and include sixteen patients) and study group (treated with diode laser 940nm and includ
... Show MoreTwo Prototypes of Transversely Excited at atmospheric pressure (TEA) Nitrogen laser systems (One Stage Blumlein Circuit and Two Stage Blumlein Circuit) were fabricated and operated. High voltage power supply with variable operating voltage (0-20 kv) and operating current (1-3A) was built and tested successfully. The gas flow rate of 15 L/ min and 10 L/ min for OSBC and TSBC was used. The performance of the fabricated systems was studied extensively reaching to the optimum operating conditions. The obtained laser output energy for the first system has linear relationship with the applied voltage. The maximum output energy was about (1.14 mJ) with (10.40) ns pulse duration and the half-wave divergence angle was about (0.1455 m rad). In the
... Show MoreFemale infection with HPV (human papilla virus) has been established as an essential cause of CIN (cervical intraepithelial neoplasia). The danger of transformation from CIN to frank malignancy should be considered. Objective: The goal of this study is to evaluate the effectiveness of CO2 laser vaporization of ectocervical lesion high grade squamous intraepithelial lesion (HGSIL). Patients and Methods: Four Female out of 150 affected with HGSIL lesions were submitted to CO2 laser vaporization and followed up in 4 months later, and 10 women with HGSIL lesion submitted to electrocautery diathermy for the comparison. Results: Among women treated by CO2 laser vaporization, 3 women had negative results (clear cervix), at 4 months follow up; o
... Show MoreIn the present work, heterojunction diode detectors will be prepared using germanium wafers as a substrate material and 200 nm tin sulfide thickness will be evaporated by using thermal evaporation method as thin film on the substrate. Nd:YAG laser (λ=532 nm) with different energy densities (5.66 J/cm2 and 11.32 J/cm2) is used to diffuse the SnS inside the surface of the germanium samples with 10 laser shots in different environments (vacuum and distilled water). I-V characteristics in the dark illumination, C-V characteristics, transmission measurements, spectral responsivity and quantum efficiency were investigated at 300K. The C-V measurements have shown that the heterojunction were of abrupt type and the maximum value of build-in pot
... Show MoreIn this study, Laser Shock Peening (LSP) effect on the polymeric composite materials has been investigated experimentally. Polymeric composite materials are widely used because they are easy to fabricate and have many attractive features. Unsaturated polyester resin as a matrix was selected and Aluminum powder with micro particles as a reinforcement material was used with different volume fraction (2.5%, 5% and 7.5%). Hand lay-up process was used for preparation the composites. Fatigue test with constant amplitude with stress ratio (R =-1) was carried out before and after LSP process with two levels of energy (1Joule and 2Joule). The result showed an increase in the endurance strength of 25.448% at 7.5% volume fraction when peened is 1J
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