objective: at present, treatment of edentulous areas with implant-supported prosthesis has greatly increased. the aim of this study was to assess the survival rate of implants with different diameters. methods: this retrospective study was conducted on 239 warfare victims presenting to qazi tabatabaie clinic during 2000-2010. a total of 1,649 implants were placed. the success criteria included ...

Let R be a commutative ring. An R-module M is called co-multiplication provided that foreach submodule N of M there exists an ideal I of R such that N = (0 : I). In this paper weshow that co-multiplication modules are a generalization of strongly duo modules. Uniserialmodules of finite length and hence valuation Artinian rings are some distinguished classes ofco-multiplication rings. In additio...

The reliability problem must be solved for achieving large-scale application about LEDs, and the temperature is a key factor to affect LED reliability. In order to find the temperature effects on the module of high-power light emitting diodes (LEDs), a finite element approach was used to study the reliability problems of LEDs under high temperature and low temperature. A thermal shock experimen...

Let $A$ be a Banach algebra, $\Omega(A)$ be the character space of $A$ and $\alpha\in\Omega(A)$. In this paper, we examine the characteristics of $\alpha$-projective (injective) $A$-modules and demonstrate that these character-based $A$-modules also satisfy well-known classical homological properties on Banach $A$-modules.

In this paper, development of a semi-two- dimensional mathematical model called SDAR is introduced. The model is composed of two principal modules of hydraulics and sediment transport. The newly developed SDAR model has a number of capabilities including determination of sediment transport rate, aggradation - degradation calculation, longitudinal profile and lateral cross–sectional variation s...

greater levels of complexity in tunnelling with tunnel boring machine (tbm) allow higher chances of failures that may increase the potential hazardous risks. this paper presents the results of a study on tbm reliability using risk analysis. machinery failure mode and effect analysis was applied to analyze the risks of a tbm using qs9000 and sae.j1739 recommendations. for this purpose, 48 failur...

background and objectives: arteriovenous fistula is a popular vascular access method for surgical treatmentof hemodialysis patients. the method, however, is associated with a high rate of early failure varying in the range of 20-60%. predicting early arteriovenous fistula failure and its risk factors can help reduce its incidence, its hospitalization rate, and associated costs. in this study, w...