Background: Photon attenuation as an inevitable physical phenomenon influences on the diagnostic information of SPECT images and results to errors in accuracy of quantitative measurements. This can be corrected via different physical or mathematical approaches. As the correction equation in mathematical approaches is nonlinear, in this study a new method of LINEARIZATION called ‘PIECE WISE LINEARIZATION’ (PWL) is introduced and to substantiate its validity for SPECT image reconstructions, a phantom study is performed. Material and Methods: A SPECT scan of a homemade heart phantom filled with 2 mCi 99mTc was acquired by dual head Siemens E.Cam gamma camera equipped with LEHR collimator. Row data of the scan were transferred in DICOM format to a pc computer for reconstruction of the images using MLEM iterative algorithm in Matlab software. Result: Attenuation map of the phantom m(x) were derived using PWL with linear optimization approach. Based on that, the attenuation corrected SPECT image of the phantom were reconstructed and compared with non-corrected image, using MLEM iterative algorithm. Comparison of the corrected and non-corrected images confirmed with CT attenuation correction method. Conclusion: Attenuation correction in SPECT image can be achieved successfully, using emission data and PIECEWISE LINEARIZATION with linear optimization approach. The corrected image of ¦(x) and attenuation map m(x) of the heart phantom using this approach promise acceptable image quality for diagnostic clinical use.

The effect of PIECE-WISE welding on thermal and mechanical response of thick plate weldments is studied by the use of a 3-D thermo-viscoplastic model. Anand’s viscoplastic model is used to simulate the rate dependent plastic deformation of welded materials. Modeling of the welded region in the present study has been done by the use of the “isothermal melting pool” approach. The temperature dependency of thermal and mechanical properties of material is considered in analysis and the effect of welder characteristics such as welding speed and welding lag between sequences are introduced into the model. In addition, the Element Rebirth Technique (ERT) is incorporated into the model to introduce the effect of welds of materials added to the weldments during the welding. The model was compared with the results of two analytical and experimental works. The results of the present model are feasible and clearly show the relation between the order of joining blocks and distribution of thermal loads. They also demonstrate the role of this kind of welding sequence on the formation of residual stresses and distortion in thick plate weldments.

The royal magnificence was passed from Fereidoun to Kayghobad and then to his six sons and grandsons. In other words, it was passed to Kayapiveh, Kaykavous, Kiarash, Kaypishin, Kaypiarash and Kaysiavash and finally to Kaykhosro. Shahnameh and words of Sohrevardi such as Avesta have mentioned the possession of wisdom by Kaykhosro and his ability to do great works and holy virtues and his immortality which were achieved by Kaykhosro, ascending him to the status of a pious disciple and a WISE theist and owner of discovery and intuition, which will be reviewed in this article in the form of an abridgement.

In the history of countries, there have always been great people whose contemporary people have boasted their existence and have always been proud of them. These great people have become a legendary figure over time for the general public through the action they have done. One of these great men who symbolized wisdom among Iranian bureaucrats and whose life was partly involved in ambiguity and myth is Bozorgmehr Hakim. In Iranian history and literature, ethical, philosophical statements, as well as words of advice and anecdotes have been attributed to him, which emphasize his wisdom and patriotism. The Iranians have presented their human values by quoting those great men who have been exemplary and tactful both in history and in the construction of legend. Undoubtedly, Bozorgmehr Hakim is one of those bright figures. He was one of the heroes who joined the group of martyrs of thought and became legendary. Thus, it is necessary to investigate his legendary and real character.

Background: Screw loosening is one of the most common problems associated with implant-supported prostheses. The type and material of the abutment play an important role in the esthetic appearance of implant-supported restorations. Metal abutments create an unaesthetic grayish halo in the gingival margin of the implant due to the reflection of light from the surface of titanium abutment. Zirconia is highly popular for the fabrication of abutments due to its optimal color, along with the quality of light transmission and its resistance. The present study aimed to evaluate the torque loss in titanium and one-and two-PIECE zirconia abutments under cyclic loading. Methods: In general, 24 abutments in three groups (n=8) of one-and two-PIECE zirconia abutments, and titanium abutments were evaluated in this experimental study. The abutments were attached to the analog of fixtures with 30 N/cm torque and the samples were subjected to loads applied to the center of abutments at 30° angle. After cyclic loading, the removal torque value was measured for each abutment and its numerical mean was calculated as well. Finally, the groups were compared using SPSS16 via ANOVA and Games-Howell tests at a 0. 05 level of significance. Results: The mean removal torque value was 23. 925, 23. 913, and 22. 538 N/cm in titanium and two-and one-PIECE zirconia abutments, respectively, with no statistically significant difference in between (P>0. 05). Conclusions: The highest mean removal torque value belonged to prefabricated titanium abutments while the lowest value was related to one-PIECE zirconia abutments.

Introduction: Some clinicians use a handheld screw driver instead of a torque wrench to definitively tighten abutment screws. The aim of this study was to compare the removal torque of one-PIECE and two-PIECE abutments tightened with a handheld driver and a torque control ratchet.Methods: 40 ITI implants were placed in acrylic blocks and divided into 4 groups. In groups one and two, 10 ITI one-PIECE abutments (Solidâ) and in groups three and four, 10 ITI two-PIECE abutments (Synoctaâ) were placed on the implants. In groups one and three abutments were tightened by 5 experienced males and 5 experienced females using a handheld driver. In groups two and four abutments were tightened using a torque wrench with torque values of 10, 20 and 35 N.cm. Insertion torque and removal torque values of the abutments were measured with a digital torque meter.Results: The insertion torque values (ITVs) of males in both abutments were significantly higher than those of females. ITVs in both Solidâ and Synoctaâ abutments tightened with a handheld screwdriver were similar to the torque of 20 N.cm in the torque wrench. Removal torque values (RTVs) of solidâ abutments were higher than those of synoctaâ abutments.Conclusion: The one- PIECE abutments (solidâ) showed higher RTVs than the two-PIECE abutments (synoctaâ). Hand driver does not produce sufficient preload force for the final tightening of the abutment.

In this paper, a detailed modeling of energy consumption in the processes of producing aluminum and cement industrial units based on the linear PIECE-WISE approximation (LPWA) method is presented. The presented model has been implemented in the day-ahead energy management planning of a microgrid including these industrial units. In order to increase the profit of the mentioned industrial units, the demand response programs are implemented and therefore these units are able to participate in the energy and ancillary services market. The energy management planning proposed in this paper, considers the exact model and all constraints of the industrial units and microgrid in order to maximize the profit of the microgrid and these units. The performance of the model and the proposed planning has been evaluated through two case studies, with and without implementation of demand response programs. In addition, the effect of the changes in the profit obtained by selling the product of each industrial unit and the prices of sold energy by microgrid to the electricity market, on the profit of the units and the microgrid, have been examined using the sensitivity analysis. The obtained results, besides validating the proposed model, show that the implementation of demand response programs and the participation of industrial units in the energy and ancillary services market, not only modifying the demand curve but also increase the profit of the microgrid and units.

Ferdowsi mostly pays attention to Persian culture and civilization, so this WISE sag's great masterPIECE is full of the WISE and cultural doctrines. According to the statement: ''Wisdom is the first thing that was created'', Ferdowsi calls wisdom the hospital of any in curable disease, which nothing will lead to success without it. In this essay, the main subject is to review, study and present precisely the efficient wisdom that have been the pattern and the main strategy of our successful and prosperous ancestors in this territory.We will present a crystallization of the WISE do ctrines of this cultural scientist to the reader's wisdom and intellect, in order to cause him to be able to use and adopt the precious pearls of these doctrines, and by using it, the reader would use his upper efforts and endeavors for the prosperity and success of this region and country, much more and better and more guiding. Besides the WISE doctrines that have been emanating our ancestor's bright success, he prohibits us from going to the ignorance road, which he calls it the Satan's astray.