Toomas Saat, Gustav Lauringson, Janek Lees,
... in two rivers of northwestern Estonia (Vääna and Maidla, 59 degrees N). Loaches in the Vääna River ... and males prevailed among older fish; in the Maidla River loaches were fast growing and females dominated ... diameter) of comparably sized loach of Vääna and Maidla were similar and intermediate between more southern and ...
Tópico(s): Marine and fisheries research
2003 - First Faculty of Medicine, Charles University | Folia Biologica
Eric Maidla, Andrew K. Wojtanowicz,
Summary This paper discusses a medium-scale borehole friction tester with dynamic-filtration capabilities that showed that friction coefficients are affected by mud quality, mudcake, and lubricant addition in low-solids, water-based muds (WBM's). Most measured values, including those from oil-based muds (OBM's), were between 0.2 and 0.3. This paper also reports on new effects of filter cake and solids deposition on borehole friction.
Tópico(s): Hydraulic Fracturing and Reservoir Analysis
1990 - | SPE Drilling Engineering
Produção Nacional
Summary A computer program was developed for the simultaneous selection of a roller-cutter bit, bit bearing, weight on bit (WOB), and drillstring rotation that minimizes drilling cost per foot for a single bit run. Two drilling models were tested with data from five wells located offshore Alagoas, Brazil. Results show that the rate of penetration (ROP) of the fifth well can be predicted with coefficients calculated from the four previous wells, resulting in cost savings.
Tópico(s): Oil and Gas Production Techniques
1991 - | SPE Drilling Engineering
... Lost Time: Theory and Case Histories,’ by Eric Maidla, SPE, and William Maidla, SPE, TDE Petroleum Data Solutions, prepared for the ...
Tópico(s): Drilling and Well Engineering
2011 - Society of Petroleum Engineers | Journal of Petroleum Technology
Xueying Wang, Hongjian Ni, Ruihe Wang, Peng Wang, Lei Zhang,
... Surface-rotation pulses can correct tool-face orientation (Maidla and Haci 2004), but the underlying mechanism, in ...
Tópico(s): Hydraulic Fracturing and Reservoir Analysis
2018 - | SPE Drilling & Completion
Eric Maidla, Andrew K. Wojtanowicz,
A field procedure to evaluate the borehole friction factor between a pipe string and a borehole was developed. The primary concern of this research was to investigate and mathematically describe the drag associated with casing runs in directional wells through the use of the two-dimensional approach. The borehole friction factor was found, through an iterative procedure, by matching the calculated hook load to the measured one at the surface. The borehole friction factor was calculated as the unique ...
Tópico(s): Hydraulic Fracturing and Reservoir Analysis
1988 - Elsevier BV | Journal of Petroleum Science and Engineering
Ain Raal, Anne Orav, Julia Nesterovitsch, Kerttu Maidla,
Pot Marigold (Calendula officinalis L.) is an annual ornamental plant with yellow to orange flowers which belongs the the Asteraceae family, its flowers are used in the pharmaceutical, cosmetic and food industries. The commercial samples of seeds (n=24) of C officinalis were cultivated in home gardens in Estonia. Total carotenoid contents, determined spectrophotometrically (λ=455 nm) in the inflorescences, varied from 0.7 to 2.7%, the cultivar with the highest carotenoid content was ‘Dracon’. The total ...
Tópico(s): Essential Oils and Antimicrobial Activity
2016 - SAGE Publishing | Natural Product Communications
Sergey Kask, Tiiu Kull, Kati Orru,
... 3DV. The study describes experiences from the Setu, Maidla, and Võrtsjärv lake regions of Estonia. The content ...
Tópico(s): Recreation, Leisure, Wilderness Management
2018 - Routledge | Journal of Baltic Studies
Produção Nacional
Revisado por pares
J. Venâncio Cordoso, Eric Maidla, L. S. Idagawa,
Abstract Most directional well drilling problems detected in Brazil, and also verbally reported by service companies abroad, occur during tripping operations. A comprehensive research program was undertaken to study this problem. The work is summarized in this paper, and shows the development of a field analysis procedure that proved to be reliable and thus translates into significant cost savings. The field data was obtained using an in-house mud logging offshore unit and service companies' drilling ...
Tópico(s): Oil and Gas Production Techniques
1995 - | SPE Drilling & Completion
... U. Leoben (now with U. of Oklahoma); Eric Maidla, SPE, Csiro Petroleum; and Simon Kravis, SPE, Csiro ...
Tópico(s): Reservoir Engineering and Simulation Methods
1999 - Society of Petroleum Engineers | Journal of Petroleum Technology
... SPE, U. of New South Wales; Eric E. Maidla, SPE, CSIRO Petroleum; and Vladimir Basovich and Mikhail ...
Tópico(s): Drilling and Well Engineering
1999 - Society of Petroleum Engineers | Journal of Petroleum Technology
... death rate was somewhat lower (38.9‰) at Maidla in the Late Iron Age and extremely high (92.1‰) at Maidla in the Middle Iron Age, which indicates an ... 4 years at Poanse II. Most likely, both Maidla I and Poanse I were unsustainable communities. According ... family or household. In comparison with other graves, Maidla II stone grave in western Estonia and Rõsna- ...
Tópico(s): Archaeology and ancient environmental studies
2018 - University of Tartu | Papers on Anthropology
Produção Nacional
Otto Santos, S.A. Petrobras, Eric Maidla, Julius P. Langllnais,
Summary A method to present directional wellbore trajectories graphically with microcomputers has been developed. This concept makes use of interactive computer graphics, enabling the user to view computer calculation results immediately. The source code was written in FORTRAN-77 and designed for use with microcomputers. Introduction The vertical and horizontal sections routinely used to evaluate directional wans are simple graphical displays that monitor the spatial position of a wellbore. These ...
Tópico(s): Hydraulic Fracturing and Reservoir Analysis
1989 - Society of Petroleum Engineers | Journal of Petroleum Technology
Produção Nacional
J. L. Roque, Eric Maidla, Richard Wagner,
Summary Casing can be the single most expensive item of an oil well and, in many cases, can be designed in a cheaper way. We present the optimization procedure, method, and algorithm to minimize cost of a combination casing string. The algorithm is general and can be used with any commercial program, provided a few modifications are made for it to be used as a subroutine. To demonstrate its use, a commercial package (that can handle complex load calculations) is tested and the results confirm the ...
Tópico(s): Drilling and Well Engineering
1996 - | SPE Computer Applications
... Iron Age (12th–13th cc.) skeletons from the Maidla grave-field. The skeletal data from Läänemaa are ...
Tópico(s): Archaeology and ancient environmental studies
2013 - University of Tartu | Papers on Anthropology
Eric Maidla, Andrew K. Wojtanowicz,
This chapter discusses the computer-aided casing design and addresses the optimization theory that results in assuring the selection of the cheapest combination casing string. After calculating the loads that the casing will be subjected to, the engineer is faced with the decision of selecting an appropriate casing grade, weight, and thread, such that these properties meet or exceed the calculated load conditions. The casing program of most oil wells represents the greatest single item of expense ...
Tópico(s): Reservoir Engineering and Simulation Methods
1995 - Elsevier BV | Developments in petroleum science