Stereo lithography (SLA) three-dimensional (3D) printing process is a type of additive manufacturing techniques that uses digital models from computer-aided design to automatically produce customized 3D objects. Around 30 years, it has been widely utilized in the manufacturing, design, engineering, industrial sectors and its applications in dentistry for manufacturing prosthodontics are very important. The stereo lithography technology is highly regarded because it can produce items with excellent precision especially when selecting the best process parameters. This review article offers a useful and scientific summary of SLA three-dimensional printing technology and its brief history. The specific type of 3D printers which is SLA type based on light curing resin and material overview is also presented. Moreover, the survey was conducted to gain substantial knowledge of the various advantages and disadvantages of SLA 3D printing. According to this study, a summary has been specified on the accuracy of SLA 3D printers and various factors that affected its accuracy and dimension measurement namely layer thickness, normal exposure time, bottom or top exposure time, post processing and room temperature. The majority of works in the literatures conducted till date are on improving the physical part attributes like dimensional accuracy and surface roughness but the improving of the mechanical properties have received less attention and need more focusing in the future works.
Fingerprint recognition is one among oldest procedures of identification. An important step in automatic fingerprint matching is to mechanically and dependably extract features. The quality of the input fingerprint image has a major impact on the performance of a feature extraction algorithm. The target of this paper is to present a fingerprint recognition technique that utilizes local features for fingerprint representation and matching. The adopted local features have determined: (i) the energy of Haar wavelet subbands, (ii) the normalized of Haar wavelet subbands. Experiments have been made on three completely different sets of features which are used when partitioning the fingerprint into overlapped blocks. Experiments are conducted on
... Show MoreThe dimensions of bubbles were measured in a stirrer tank electrochemical reactor, where the analysis of the bubble size distribution has a substantial impact on the flow dynamics. The high-speed camera and image processing methods were used to obtain a reliable photo. The influence of varied air flow rates (0.3; 0.5; 1 l/min) on BSD was thoroughly investigated. Two types of distributors (cubic and circular) were examined, and the impact of various airflow rates on BSD was investigated in detail. The results showed that the bubbles for the two distributors were between 0.5 and 4.5 mm. For both distributors at each airflow, the Sauter mean diameter for the bubbles was calculated. According to the results, as the flow rate raised, the bubb
... Show MoreA critical milestone in nano-biotechnology is establishing reliable and ecological friendly methods for fabricating metal oxide NPs. Because of their great biodegradable, electrical, mechanical, and optical qualities, zirconia NPs (ZrO2NPs) attract much interest among all zirconia NPs (ZrO2NPs). Zirconium oxide (ZrO2) has piqued the interest of researchers throughout the world, particularly since the development of methods for the manufacture of nano-sized particles. An extensive study into the creation of nanoparticles utilizing various synthetic techniques and their potential uses has been stimulated by their high luminous efficiency, wide bandgap, and high exciton binding energy. Zirconium dioxide nano
... Show MoreIn this paper, point estimation for parameter ? of Maxwell-Boltzmann distribution has been investigated by using simulation technique, to estimate the parameter by two sections methods; the first section includes Non-Bayesian estimation methods, such as (Maximum Likelihood estimator method, and Moment estimator method), while the second section includes standard Bayesian estimation method, using two different priors (Inverse Chi-Square and Jeffrey) such as (standard Bayes estimator, and Bayes estimator based on Jeffrey's prior). Comparisons among these methods were made by employing mean square error measure. Simulation technique for different sample sizes has been used to compare between these methods.
Man always reacts by employing data that he lives inside Artworks and he tries to make them an ideal speech that shows the most important intellectual trends to which he belongs, as it happened in the formal building of the ancient arts . Mesopotamia is one of the civilizations that interacted with the intellectual legibility transforming into visual symbols, so it is difficult for the researcher to interpret these symbols without considering the nature of these civilizations in general .
This current search aims to identify similarities and differences in the recruitment of cultural shapes between the works of the sculptors (Mohammed Ghani Hikmat and Murtada Haddad) .
Researcher adopted an approach of analytical description of the
Objective: Certain advantages of donkeys are still not listed as for other equine species. Moreover, donkeys lack comprehensive scientific studies. The present study examines the histological architecture and histochemical characteristics of the esophagus in the Iraqi local breed donkey (Equus asinus). Materials and Methods: Eight esophagus samples were collected from a local breed donkey. Tissue specimens (~1 cm³) were collected from the cervical, thoracic, and abdominal regions of the esoph¬agus and processed via routine histological technique. The tissue sections were stained with hema¬toxylin and eosin, Massons Trichrome, and combined Alcian blue (pH 2.5) plus PAS (AB-PAS). Results: The esophagus of the local breed donkey h
... Show MoreAllah the Almighty has honored many of his slaves in the high houses for their efforts in building the scientific edifice of this nation, by demonstrating what is needed from the legal provisions for all the relations between them, and the actions that they emanate from. The tasks of the abbreviations and Almstsot, and deposited in the mabahith after various investigations and precious precious matters and showed all the human needs in his life and what is expected to happen, even on the rarest possibilities, and their efforts that left the nation on the cases of Goliath. , And Ask They are in Dar dignity with the best creatures and make us a share of those good things, and Odamna to obey Him and His pleasure until death, and forgive us
... Show MoreThe importance of this research lies in developing a psychological expenditure scale and its relationship to the passing skills of specialized volleyball players. The research problem focused on psychological expenditure as one of the problems and challenges faced by specialized players and its negative impact, such as poor skill performance, which is reflected in the performance of the player and the team. This weakens the player's self-confidence and concentration and affects the team's performance in tournaments as well as their performance in training. The research aims to develop a psychological expenditure scale, and the researcher used the descriptive approach as it is appropriate for the nature of the research problem. The f
... Show Moreconversation is an oral skill in which two persons can exchange their ideas, thoughts and opinions to communicate with each other. Learners can work in pairs or groups to practice dialogues chosen by the teacher from their textbook materials or from additional resources. Nowadays, because of Corona virus infection, our college students are taught all the subjects including conversation course either via google classroom platform or any other platforms. Google meet is one of online meetings between the teacher and students, i.e., a video meet in which students and the teacher join the online meetings in a specified time to communicate, express their ideas, thoughts and feelings about what is mentioned above. In this study, the resea
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