Parametric Investigation of the Stability of Vessels for Float-Over Deck Transportation

Author(s):  
Lee O’Neill ◽  
Shaun O’Brein ◽  
Emmanuel Fakas

The technical challenge of transporting large size integrated decks, especially float-over decks at high elevation, is well recognised. The cost of such operation usually forms a significant part of the overall development cost, especially in remote parts of the world where the transport routes are longer and the transport vessel choice is limited. In this respect, suitable vessel selection is very critical in terms of the economic viability of oil and gas developments, especially of marginal fields. A cost-effective working method is developed for selecting suitable vessels for a wide range of transport options (deck weights and transport elevations) without the requirement of extensive analyses. This method may be used at the very early stages of any study to assess the feasibility of the transport concept and also provide a wider choice of feasible options to be considered at the next stage of the development, where a more accurate analysis may be justified. Some potential ways for improving vessel stability are also investigated. Findings from the study can also be applied to integrated deck salvage transport.

1983 ◽  
Vol 2 (1) ◽  
pp. 67-79
Author(s):  
Martin T. Katzman

Several American utilities have contracted to purchase electricity from ‘windfarmers’, and many others are beginning to explore this option. The value of conventional fuel and capacity savings will influence the terms under which utilities enter these contracts. A quantitative assessment of these savings is undertaken using computer models that simulate the dispatching of conventional capacity and calculate the reliability of this capacity. These models identify the conventional costs avoided by utilities as a consequence of windfarming. The impact of various levels of windmill penetration is simulated in five sites in the USA, representing a wide range of average wind speeds. The cost of wind energy is less than the value of fuel savings alone for utilities which possess substantial oil- and-gas-fired generating capacity and which serve sites with winds above 12 m.p.h. In such sites, 1kW of conventional capacity is displaced by 2–5 kW windmill capacity. Increased windmill penetration reduces the value of fuel and capacity savings per kW.


Author(s):  
Daniel B. Hess ◽  
Brian D. Taylor ◽  
Allison C. Yoh

Bus rapid transit (BRT) is growing rapidly in popularity because it is viewed widely as an efficient and effective means to improve both transit service and patronage. This paper argues that two distinct views of BRT are emerging: ( a) BRT as a new form of high-speed, rubber-tired, rail-like rapid transit and ( b) BRT as a cost-effective way to upgrade both the quality and image of traditional fixed-route bus service. These two views carry different price tags because the cost of planning, constructing, and operating BRT depends on the complexity of new service features and on rises for BRT that offer service characteristics approaching those of light rail. This study fills a gap in the literature on the costs of BRT by examining in detail component costs–-actual costs for recently implemented services and projected costs for planned new services–-for a sample of BRT systems in North American cities. The study examined BRT costs of 14 planned and recently opened BRT systems to determine how the wide range of BRT service and technology configurations affect costs. The study found that although some of the most successful and popular new BRT systems are high-quality services operating in mixed traffic and implemented at relatively low cost, most BRT projects on the drawing boards are more elaborate, more expensive systems than many currently in service. Most new BRT projects emphasize elaborate LRT-type improvements to lines and stations in one or a few corridors rather than less splashy improvements (such as next-bus monitors, signal preemption, queue-jump lanes, and so forth) affecting more lines and modes in local transit networks. Among the 14 systems examined here, most could be characterized as light rail lite.


2009 ◽  
Vol 27 (15_suppl) ◽  
pp. 6570-6570
Author(s):  
K. B. Tong ◽  
E. Chen ◽  
G. Brink ◽  
R. Bender ◽  
F. de Snoo ◽  
...  

6570 Background: The 70-gene microarray test (MammaPrint) has been shown to provide additional prognostic information to clinicopathologic risk assessment for women ESBC; however, the cost-effectiveness of this strategy is not well understood. Methods: The objective of this analysis was to estimate the incremental benefits, costs, and cost-effectiveness of the treatments guided by the 70-gene signature versus Adjuvant! Software (AS) to decide on the use of adjuvant chemotherapy for women ≤61 years with lymph node negative, HER-2 negative ESBC with estrogen receptor (ER) positive or negative disease. A Markov model with a lifetime horizon and three health states (alive without recurrence, death from cancer and death from other causes) was constructed using TreeAge Pro software. Risk classification and patient outcomes data were based on a multi-center 70-gene signature validation study. Efficacy of chemotherapy derived from published meta-analysis of clinical trials. Costs and health utilities were obtained from the literature. Costs and benefits were discounted 3%/year. Results: Compared to AS, the 70-gene signature strategy resulted in 35% of patients being reassigned to a different risk classification and avoided chemotherapy in 9% of patients. In the base case, the 70-gene signature strategy was cost neutral (lifetime costs per patient: $178,811 versus $178,893 for the 70-gene signature and AS strategy). Moreover the 70-gene signature strategy was associated with an increase of 0.13 life years (LYs) and 0.16 quality adjusted life years (QALYs). The model results were sensitive to the cost of 70-gene signature test, cost of adjuvant chemotherapy, and relative risk reduction associated with chemotherapy; however, the 70-gene strategy remained cost-effective across a wide range of assumptions. Conclusions: In this analysis, the 70-gene signature was associated with a reduction in chemotherapy use and an increase in life expectancy. The 70-gene signature appears to be a cost-effective strategy for obtaining additional information to guide the decision to use adjuvant chemotherapy in patients with lymph node negative ESBC. [Table: see text]


2021 ◽  
Vol 11 (1) ◽  
pp. 26-39
Author(s):  
Lipei Fu ◽  
Qianli Ma ◽  
Kaili Liao ◽  
Junnan An ◽  
Jinmei Bai ◽  
...  

Abstract When surfactant is used as emulsifier, the stability of emulsion is often greatly reduced with the influence of reservoir conditions (temperature, pressure, salinity, etc.), which shortens the validity period of emulsion. Pickering emulsion has a wide range of applications in the oil and gas field due to its advantages of good stability and easy regulation. In this article, the formation, stabilization mechanism, and influencing factors of Pickering emulsions were introduced, and the application status and prospects of Pickering emulsions in oil and gas field were summarized. It was pointed out that Pickering emulsion has many advantages and important research value when applied in deep strata and complicated reservoirs. It is expected that this article can effectively reflect the application value of Pickering emulsion in oil and gas field and promote the application of Pickering emulsion in petroleum industry.


Author(s):  
Luqman Raji ◽  
Zhigilla Y.I ◽  
Wadai J

Nigeria is one of developing countries in the world that experience shortage of electricity for her economic and social development. In Nigeria, most of the small-scale industries use diesel/petrol-based systems to generate their electricity. However, due to the cost fluctuation of oil and gas fuel, an alternative power generation should be considered. This paper targets to examine the cost analysis of system for supplying electricity to LUMATEC Aluminium products shop in Mubi, Adamawa state Nigeria. Hybrid Optimization Model for Electric Renewable (HOMER) is used as a tool for cost analysis. The scenario consider in this study was only stand-alone with battery system. Results revealed that the system have 10kW PV with cost of electricity (COE) of $0.312/kW. The initial capital cost and total net present cost (NPC) are $21.775 and $26.148 respectively, with payback period of 5.8years. In conclusion, this study provides the solution of power supply to the small-scale industries at cost effective and available throughout the year and it is feasible to solve the small-scale industries, rural and urban electricity supplying in this country (Nigeria). It is recommended that Nigerian Government & Law makers should promotes the use of standalone PV system for domestic and small-scale industry by providing financial assistance through soft loans, subsides and grants.


Author(s):  
Lucile M. Quéau ◽  
Mehrdad Kimiaei ◽  
Mark F. Randolph

Offshore exploration and production of oil and gas continue to increase and move into ever deeper water. Steel catenary risers (SCRs) are one of the most cost effective type of risers in deep water. However, high sensitivity to vessel motions and hydrodynamic loading in the touchdown zone may limit the feasibility of SCR applications. In recent years, there has been a growing interest in the use of Lazy-wave catenary riser (LWR) due to their better fatigue performance in the touchdown zone through the damping effect of the buoyancy section. The design of LWR involves numerous parameters that lead to a wide range of configurations. Each of these configurations needs to be evaluated against several criteria with respect to geometry, strength and fatigue for instance. This paper presents how tools recently proposed to improve the design of standard SCRs can be extended to benefit LWR applications. The dimensionless groups governing the structural response of LWRs are established in the aim of easing sensitivity analysis to key input parameters for LWR design, assisting experiments and reducing the number of numerical simulations. Moreover, the DAF (dynamic amplification factor) approach for dynamic response which has previously been explored for SCRs could also be used to simplify design of LWRs. As DAF relies on the analytical determination of static response, this framework shows that analytical boundary layer solutions in conjunction with the use of a Winkler type soil model can efficiently and accurately predict the static stress range of LWRs observed in the TDZ.


Author(s):  
Rachel Nicholls-Lee ◽  
Simon Hindley ◽  
Richard Parkinson

In order for tidal stream technology to develop into a viable and cost effective energy solution, the overall cost of tidal array installation, operations and maintenance must be driven down. The key issues which drive the cost are the time required to conduct operations and susceptibility to weather risk coupled with the expense of marine assets. Current vessels have limited operational windows due to weather and tidal constraints, which result in considerable cumulative costs due to high charges for such vessels. The marine renewable industry is currently reliant on vessels of opportunity from the offshore oil and gas sector; which, while sufficient for single device demonstration deployments, are not viable for array installations. De-coupling the tidal sector from this market place offers the opportunity to reduce the volatility of vessel day rates. This paper presents the concept design of an efficient and economic, fit for purpose installation vessel for tidal stream energy converters. The vessel has good dynamic positioning capabilities for operation in strong tidal currents thus broadening the operational window. The environmental impact of the vessel is reduced when compared to existing vessels. A key criterion throughout the design process is minimizing the cost of the vessel to tidal turbine site developers.


2021 ◽  
pp. 130-137
Author(s):  
S. K. Mizanbekova ◽  
◽  
B. B. Kalykova ◽  
D. A. Aitmukhanbetova ◽  
◽  
...  

Purpose – complex multifunctional and dynamic system, which includes a wide range of national economic functions, which is represented by grain farming, and requires priority attention to its development from the state has been analyzed. It is noted that the stability of grain trade, functioning of national and general grain markets depend on the quantity, quality, species range and price level of grain produced, demand, government influence on its production and sale, situation on the world grain market and other factors of an internal and external nature. The research methods are reflected in the improvement of territorial division of labor in the process of grain production and development of grain trade between countries, taking into account the scientific approach to the development and implementation of projects and programs of an interstate association, which should be comprehensive and take into account the positive aspects and barriers in expanding the single grain market. Results – it was revealed that innovative activity, promising innovations for the systems of breeding and seed production of grain crops, development of mechanization, land reclamation, chemical processing, expansion and strengthening of transport routes, information support, management in the fields of grain production and market relations allow the formation of specialized grain zones. Conclusions – in Kazakhstan, it is necessary to create a domestic accounting system in accordance with interstate agreements, according to which, in 2022, a mechanism for the identification and traceability of grain should function in the EAEU. It will require its development, similar to dairy products, which will significantly increase the cost of using these technologies.


2021 ◽  
Vol 23 (1) ◽  
Author(s):  
Nahid Javanshir ◽  
Golsa Nayeb Ghanbar Hosseini ◽  
Mahdieh Sadeghi ◽  
Ramtin Esmaeili ◽  
Fateme Satarikia ◽  
...  

AbstractDue to the importance of using cost-effective methods for therapeutic purposes, the function of probiotics as safe microorganisms and the study of their relevant functional mechanisms have recently been in the spotlight. Finding the mechanisms of attachment and stability and their beneficial effects on the immune system can be useful in identifying and increasing the therapeutic effects of probiotics. In this review, the functional mechanisms of probiotics were comprehensively investigated. Relevant articles were searched in scientific sources, documents, and databases, including PubMed, NCBI, Bactibace, OptiBac, and Bagel4. The most important functional mechanisms of probiotics and their effects on strengthening the epithelial barrier, competitive inhibition of pathogenic microorganisms, production of antimicrobials, binding and interaction with the host, and regulatory effects on the immune system were discussed.In this regard, the attachment of probiotics to the epithelium is very important because the prerequisite for their proper functioning is to establish a proper connection to the epithelium. Therefore, more attention should be paid to the binding effect of probiotics, including sortase A, a significant factor involved in the expression of sortase-dependent proteins (SDP), on their surface as mediators of intestinal epithelial cell binding. In general, by investigating the functional mechanisms of probiotics, it was concluded that the mechanism by which probiotics regulate the immune system and adhesion capacity can directly and indirectly have preventive and therapeutic effects on a wide range of diseases. However, further study of these mechanisms requires extensive research on various aspects.


Author(s):  
Nikhil Dave ◽  
Katie Sue Pascavis ◽  
John Patterson ◽  
David Wallace ◽  
Abhik Chowdhury ◽  
...  

AbstractDue to the virulence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the pathogen responsible for the respiratory disease termed COVID-19, there has been a significant increase in demand for surgical masks and N95 respirators in medical clinics as well as within communities operating during the COVID-19 epidemic. Thus, community members, business owners, and even medical personnel have resorted to alternative methods for sterilizing face coverings and N95 respirators for reuse. While significant work has shown that vaporized hydrogen peroxide (VHP) can be used to sterilize N95 respirators, the cost and installation time for these sterilization systems limit their accessibility. To this end, we have designed and constructed a novel, cost-effective, and scalable VHP system that can be used to sterilize N95 respirators and other face coverings for clinical and community applications. N95 respirators inoculated with P22 bacteriophage showed a greater than 6-log10 reduction in viral load when sterilized in the VHP system for one 60-minute cycle. Further, N95 respirators treated with 20 cycles in this VHP system showed comparable filtration efficiency to untreated N95 respirators in a 50 to 200 nanometer particulate challenge filtration test. While a 23% average increase in water droplet roll-off time was observed for N95 respirators treated with 5 cycles in the sterilization, no breakdown in fluid resistance was detected. These data suggest that our VHP system is effective in sterilizing N95 respirators and other polypropylene masks for reuse. Relating to the present epidemic, deployment of this system reduces the risk of COVID-19 community transmission while conserving monetary resources otherwise spent on the continuous purchase of disposable N95 respirators and other face coverings. In summary, this novel, scientifically validated sterilization system can be easily built at a low cost and implemented in a wide range of settings.


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