Progressive Collapse Approach Compared to the Traditional Temperature Screening on Structural Assessment of Offshore Structures Against Fire

Author(s):  
Paula T. Nascimento ◽  
Marco A. P. Rosas ◽  
Leonardo Brandão ◽  
Fernando Castanheira

The present study compares the progressive collapse approach with the traditional temperature screening method on determination of PFP requirements at topside offshore structures. The advantage to evaluate the consequences of fire scenarios on the global integrity and stability of topside modules can be revealed by a substantial reduction of the required amount of PFP, and consequently significant cost savings for operators, when compared to the traditional approach. In the case study presented in this paper, there is a reduction of 79% in PFP allocation.

1996 ◽  
Vol 26 (3) ◽  
pp. 368-375
Author(s):  
Andrew F. Howard ◽  
Dag Rutherford ◽  
G. Glen Young

This paper presents the findings of a study on the economically optimal spacing of skyline corridors in partial cuts in second-growth stands of British Columbia. The mathematical basis for optimal spacing of corridors is presented for rectangular settings when trees are felled in a herring-bone pattern to facilitate yarding. The model is used in a case study where optimal spacing is compared with actual spacing for two yarding systems observed in the field. The results indicate that significant cost savings are possible from spacing skyline corridors at the optimal distance compared with conventional spacing used by the logging contractors.


2014 ◽  
Vol 2014 ◽  
pp. 1-18 ◽  
Author(s):  
Bogdan Ksiezopolski ◽  
Tomasz Zurek ◽  
Michail Mokkas

Recent research indicates that during the design of teleinformatic system the tradeoff between the systems performance and the system protection should be made. The traditional approach assumes that the best way is to apply the strongest possible security measures. Unfortunately, the overestimation of security measures can lead to the unreasonable increase of system load. This is especially important in multimedia systems where the performance has critical character. In many cases determination of the required level of protection and adjustment of some security measures to these requirements increase system efficiency. Such an approach is achieved by means of the quality of protection models where the security measures are evaluated according to their influence on the system security. In the paper, we propose a model for QoP evaluation of security mechanisms. Owing to this model, one can quantify the influence of particular security mechanisms on ensuring security attributes. The methodology of our model preparation is described and based on it the case study analysis is presented. We support our method by the tool where the models can be defined and QoP evaluation can be performed. Finally, we have modelled TLS cryptographic protocol and presented the QoP security mechanisms evaluation for the selected versions of this protocol.


2019 ◽  
Vol 14 (4) ◽  
pp. 921-930 ◽  
Author(s):  
D. Zikakis ◽  
J. Chauzy ◽  
I. Droubogianni ◽  
A. Georgakopoulos

Abstract In order to improve the energy footprint of Psyttalia wastewater treatment plant (WWTP) in Athens, the application of a thermal hydrolysis process (THP) was preferred to the option of constructing additional digesters. Since August 2015, approximately half of the generated waste activated sludge (WAS) has been treated by a Cambi B6-4 system, while the thickened primary sludge (PS) is by-passing the THP and is mixed with the hydrolysed WAS before entering the 4 digesters. The 4 other conventional digesters have treated the remaining sludge. The dewaterability of the mixed digested sludge has significantly been improved from 22% dry solids (DS) before THP installation, up to 31% DS after THP installation. This is providing substantial reduction of energy use and cost savings at the sludge drying plant of Psyttalia. In addition, biogas generation and digester efficiency (VSR) have been increased.


Author(s):  
Sh. Karimkashi ◽  
M. Amidpour

In large processing sites the cost of fuel and power can be very significant and better management of the utility system can lead to significant cost savings. The R-curve is an analysis tool that provides guidelines for the cogeneration efficiency for a given site power-to-heat ratio demand of an ideal utility system. In this paper, the actual R-curve is combined with another graphical tool, representing the cost of cogeneration potential of a site. In fact in each case, actual R-curve is constructed and then another curve of ‘R-ratio vs. TAC’ is constructed to demonstrate the cost of each point of the R-Curve. Finally showing the results obtained for a case study, it is suggested to change sizes of the turbines in the utility system to improve the R-curve and also decrease the TAC for the same R-ratios. These changes are almost dependent to the case being studied.


Author(s):  
Graham D. Bruce

SUNcast Polyurethanes Inc. has developed a proprietary process technology that makes it possible to rebuild worn Polyurethane (PU) discs, cups and solid cast pipeline pigs. The technology creates a completely secure bond between the virgin and cured cast elastomer PU enabling rebuilt parts to perform “as new”. This paper addresses the mechanical characteristics of the bond possible with this technology and offers the results of a case study on a successful program to rebuild over fifty 24″ solid cast pigs for a crude oil pipeline. Cast elastomer PU is an expensive thermoset polymer which has not been readily recyclable. SUNcast’s technology offers pipeline operators, contractors and inspection companies an opportunity to recycle what is now waste back into high performance pigging products at significant cost savings.


TAPPI Journal ◽  
2012 ◽  
Vol 11 (10) ◽  
pp. 9-17
Author(s):  
ALESSANDRA GERLI ◽  
LEENDERT C. EIGENBROOD

A novel method was developed for the determination of linting propensity of paper based on printing with an IGT printability tester and image analysis of the printed strips. On average, the total fraction of the surface removed as lint during printing is 0.01%-0.1%. This value is lower than those reported in most laboratory printing tests, and more representative of commercial offset printing applications. Newsprint paper produced on a roll/blade former machine was evaluated for linting propensity using the novel method and also printed on a commercial coldset offset press. Laboratory and commercial printing results matched well, showing that linting was higher for the bottom side of paper than for the top side, and that linting could be reduced on both sides by application of a dry-strength additive. In a second case study, varying wet-end conditions were used on a hybrid former machine to produce four paper reels, with the goal of matching the low linting propensity of the paper produced on a machine with gap former configuration. We found that the retention program, by improving fiber fines retention, substantially reduced the linting propensity of the paper produced on the hybrid former machine. The papers were also printed on a commercial coldset offset press. An excellent correlation was found between the total lint area removed from the bottom side of the paper samples during laboratory printing and lint collected on halftone areas of the first upper printing unit after 45000 copies. Finally, the method was applied to determine the linting propensity of highly filled supercalendered paper produced on a hybrid former machine. In this case, the linting propensity of the bottom side of paper correlated with its ash content.


2016 ◽  
pp. 64-66
Author(s):  
S.Yu. Vdovichenko ◽  

The objective: to show a role of the family focused technologies in depression of frequency of pathology of pregnancy at women of high obstetric risk. Patients and methods. For determination of efficiency of prophylaxis of pathology of pregnancy on the basis of use of the family focused technologies complex clinical-psychological and laboratory and tool examination of 300 women with factors of obstetric risk which were divided into two groups was conducted. In the main group – 182 women with motivation on partner labors to which provided training on system of individual preparation of married couple to labors. The comparison group consisted of 118 women who were not in prenatal training and had individual support in childbirth, with the traditional approach to pain management. Results. Use of the family focused technologies during pregnancy allows to reduce significantly the frequency of the main complications of pregnancy, especially not incubation and premature births. Conclusion. In our opinion, the technique is simple, available and can widely be used in practical health care at women with high obstetric risk. Key words: obstetric risk, the family focused technologies, prophylaxis.


Author(s):  
Y. D. Mulia

For S-15 and S-14 wells at South S Field, drilling of the 12-1/4” hole section became the longest tangent hole section interval of both wells. There were several challenges identified where hole problems can occur. The hole problems often occur in the unconsolidated sand layers and porous limestone formation sections of the hole during tripping in/out operations. Most of the hole problems are closely related to the design of the Bottom Hole Assembly (BHA). In many instances, hole problems resulted in significant additional drilling time. As an effort to resolve this issue, a new BHA setup was then designed to enhance the BHA drilling performance and eventually eliminate hole problems while drilling. The basic idea of the enhanced BHA is to provide more annulus clearance and limber BHA. The purpose is to reduce the Equivalent Circulating Density (ECD,) less contact area with formation, and reduce packoff risk while drilling through an unconsolidated section of the rocks. Engineering simulations were conducted to ensure that the enhanced BHA were able to deliver a good drilling performance. As a results, improved drilling performance can be seen on S-14 well which applied the enhanced BHA design. The enhanced BHA was able to drill the 12-1/4” tangent hole section to total depth (TD) with certain drilling parameter. Hole problems were no longer an issue during tripping out/in operation. This improvement led to significant rig time and cost savings of intermediate hole section drilling compared to S-15 well. The new enhanced BHA design has become one of the company’s benchmarks for drilling directional wells in South S Field.


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