A Four-Step Safety Integrity Level Analysis of Numerous Subsea Control System Components

In this paper, a four-step Safety Integrity Level (SIL) analysis is developed to analyze numerous components of the subsea control system based on the OREDA database. For this purpose, initially, a failure mode classification table is provided aiming to identify the number of dangerous as well as the prevalent failure modes. Then, several parameters such as the total time in service of the components are calculated. Also, failure rates are evaluated and the software checking is provided as the final step of the proposed framework. The results show that the number of dangerous failure modes is a noticeable value and the leakage in closed position is the failure mode occurring more than the other ones. Moreover, the quantification of parameters indicates that the process isolation valve of the subsea X-mass tree has the largest values in all the considered parameters. Besides, hydraulic coupling of the choke module and HC leak sensor are the two components with the highest value of failure rates.

Effects of 1-Ethyl-3-(3-Dimethylaminopropyl) Carbodiimide on Adhesion of Posts in Teeth Obturated With Different Sealers

The aim of this study was to evaluate the effect of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) on bond strength of fiberglass posts in root canals obturated with different endodontic sealers. Seventy-eight mandibular premolars were obturated with three sealers (n=26): Endofill (END), AH Plus (AHP), and Endosequence BC Sealer (EBS). After preparation of the post space, two subgroups were formed according to the cementation of the posts (n=13): with EDC (EDC), and without EDC (control - CON). The specimens were submitted to a pull-out test, failure mode classification, and root canal surface evaluation by scanning electron microscopy after post displacement. Regarding the bond strength, a significant difference between the EDC and CON subgroups occurred only in the END (p=0.001). No difference was detected among the CON subgroups (p=0.339). However, among the EDC subgroups, AHP presented significantly higher values (END versus AHP: p=0.001; AHP versus EBS: p=0.016). Upon classification of failure modes, score 1 (≥ 50% of cement) was the most commonly observed, except for the END + EDC. Remains of endodontic sealers and resin cements were found in the cervical third, but without statistical difference (p=0.269), while in the middle third, difference occurred (p=0.004). In conclusion, EDC decreases bond strength when associated with END sealer, without changing the failure mode between the resin cement and fiberglass post. The best performance was observed when EDC was combined with AHP sealer.

A database of test results from steel and reinforced concrete infilled frame experiments

Extensive experimental investigations into the behavior of reinforcement concrete and steel frames with infill have been conducted worldwide. However, there are very few systematically created and publicly available databases on infilled frame experiments. This article assembles a database of 264 experiments on single-story infilled frames, which includes specimens with different types of frames and panels. It has been utilized by the authors (in separate studies) to develop (1) empirical equations for modeling the infill panels as equivalent struts and (2) machine learning models for failure mode classification. The intent is for the database to be augmented and further used in various other applications in studying the seismic behavior of masonry-infilled frames.