Stabilizing rowing boats: Equilibrium rigging design

I. Background a. ARCO Experience as a GOM Jack-up User ARCO Oil and Gas Company (ARCO) has operated jack-ups in the Gulf of Mexico (GOM) extensively over the last three decades. During this period, ARCO has drilled several hundred wells accumulating significant experience with a variety of different jack-ups. In 1980, ARCO initiated a structural study to assess the risk of using jack-ups adjacent to fixed platforms. While the study was ongoing, a jack-up rig drilling an exploratory well for ARCO was destroyed during Hurricane Allen, further increasing interest in the subject. In the Spring of 1985, a work group of drilling, geotechnical, and marine engineers was assembled to review GOM jack-up operations and identify areas for improvement. As part of this effort, ARCO funded a compilation of GOM soil strength data, a key factor in jack-up design. The group also worked closely with a rig designer-builder to prepare a preliminary design for a new generation jack-up for GOM operations. The purpose of this paper is to present some of the observations made as a result of this general operating experience and these detailed engineering studies. It is hoped that by promoting more discussion on GOM jack-up designs that the industry (rig designers and builders, drilling contractors, and petroleum operators) will begin design work toward the next generation GOM jack-up. b. Areas for Possible Improvement Two areas were studied in detail: Operating Efficiency and Structural Integrity. Evaluation of operating efficiency reveals relationships between rig designs and final operating costs. For example, drilling records show the cost of certain rig design limitations on drilling operations. Also, by reviewing new technology and benefits from its use, estimates can be made for drilling improvements from advanced rig capabilities. Evaluation of structural integrity reveals the risk associated with failure of the unit during severe environmental loading. In the GOM, hurricanes are the environmental conditions of concern. Challenges exist both in accurately quantifying these storm conditions and consistently applying them to different offshore structures, i.e. MODU-A vs. MODU-B, MODU vs. a fixed platform. c. GOH Focus but Global Concept This paper is focused towards GOM operations since it is a dominant petroleum region warranting specialized rig designs. The concept of an operations-based decision perspective for rig design applies globally however. II. Profile of Present Fleet a. Calendar and Technical Age A survey of GOM jack-ups showed average rig age is 8 years, and only 7 of 185 rigs have been built in the last 3 years. With a useful average jack-up life of 12-15 years, there may be a shortage of good rigs in the near future. More important than calendar age is the "technical age" of the rigs. Although difficult to quantify exactly, the design, contracting, and construction process for jack-ups results in at least 2 to 3 years of lag time between technology and rig completion. For example, an 8 calendar year old rig, will be designed with technology that is 10 or 11 years old. This lag time on technology makes the above age distribution of great concern.

The Drilling Systems Automation Technical Section (DSATS) is a group of SPE volunteers from many nations, connected by their belief that drilling automation will have a long-term, positive influence on the drilling industry. DSATS implemented a student competition to encourage new entrants into the drilling industry who might consider creating and using automation tools and techniques in future drilling programs. The competition brings a hands on approach to the complex, multifaceted problem of drilling systems, expanding the breadth of knowledge and creative thought processes of the individuals who participate. This project challenges students who plan to become petroleum engineers and other students in related disciplines who may not currently think of the upstream drilling industry as a career opportunity. The competition requires university teams to design and build laboratory-scale drilling rigs to automatically drill through a sample of material unknown to the students. This paper presents the winning students' summary of the rig design, construction and operation of their test results and how it relates to their new understanding of the drilling process. In the fall of 2014, student teams from different petroleum engineering schools designed a rig that can drill through a concrete block filled with unknown formations while dealing with a drill bit and drillpipe chosen to ensure some common drilling dysfunctions. Based on the rig design, finalists from four universities were selected to move to the second phase of the competition (i.e. construction and testing phase). In the early-spring of 2015, the teams built their rigs. In May and June, they demonstrated the performance of their rig design and control algorithms by drilling the samples while witnessed by DSATS members.. The winning team received a travel grant to attend the ATCE to present this paper that addresses: Drilling limitations and critical parameters Construction issues and initial operations that required a re-design Final design criteria, constraints, tradeoffs How key decisions were determined Summary of recorded data and key events Drilling parameters and how they impacted the test Economic considerations Significant new team learnings Other items of interest Conclusions and recommendations We believe this to be the first competition of this kind that requires multi-disciplinary teams to work jointly within a university setting, which prepares them for the integrated team approach currently in use throughout our industry. Their designs are practical, but are not limited by the historical features that are commonly included in today’s commercial rig designs.

As access to the world's known energy reserves is constrained, interest in exploration and development of remote regions continues to grow. A common feature of frontier development is a fragile environment and high operating costs requiring unique operating methods. In instances where offshore reservoir targets lie near remote shorelines, extended reach technology and experienced people have minimized the impact of drilling operations on the environment while still allowing development of reserves in these sensitive areas. Since high departure wells are more complex and expose the rig, crew, BHA and tubulars to a unique set of drilling variables, cost effective operations require higher equipment specification, drilling and tripping control, and reliability. Downhole ERD technologies have focused on overcoming drag forces that prevent pipe from sliding, and rotating friction which increases torque requirements while drilling. Throw ratios of today's ERD wells have increased three-fold by employing purpose built drilling rigs, special techniques for running casing, high torque top drives and drill pipe connections, high capacity, high pressure mud pumps and large drill strings. Nevertheless, well trajectories being planned today have such departures and complexity that feasibility risk is a critical part of the evaluation prior to investing in these projects. This risk in large part is determined by the rig design and capacity to drill these "Extreme Reach" well designs. To best leverage todayâ??s directional drilling technology and successfully drill reservoir targets previously beyond technical limits, the right drilling rig is therefore required. ERD rig technology addresses extreme tubular lengths, offline stand building, increased power and hydraulic requirements to reach total depth. This paper focuses on aspects of land rig design, procedures and operations which enable us to continue to drill more complex well trajectories with still higher departures. Especially in a period of new land rig construction, the design and specification of extreme reach drilling rigs will become increasingly important as frontier regions are developed. Successful delivery of these new designs can open new markets previously considered undrillable with the existing, available rig fleet. Early experience There are numerous examples of how extended reach drilling technology has advanced. Prudhoe Bay's original multi-well development drilling programs from pad-based surface locations required directionally drilled well trajectories to reach bottomhole targets from a small surface area. Improved BHA technology at the time and increased rig hydraulic capacities enabled extended reach drilling where horizontal displacement was at least twice that of vertical depth. Besides increasing well productivity, the technique served mainly as an environmental system to limit location impact and avoid surface "obstacles". Improvement of directional drilling technology and departure limits drove progressively smaller pad size. New rig designs were therefore required to fit the rig on site while still allowing transportation access and simultaneous drilling and production activities. Elimination of pits and new cantilever designs were also implemented to fit the rig between more tightly spaced wellheads.

The research purpose. Against the backdrop of the obvious problem of overload in the modern Olympic program, the author offers his vision for optimizing the structure of the Olympic Games. Research methods. The large number of sports included in the Summer Olympic Games overload the Games program, require large expenses for their holding and reduce the value of the Olympic competitions. The author proposes to solve this problem by isolating all water sports from the program into separate Water Olympic Games, which should be held a year before the Summer Games, as well as excluding from the program of the Olympic Games into a separate block the 4 most popular team sports (football, basketball, volleyball, hockey) with the recognition of world championships in these sports as Olympic competitions. The results of the research. The proposed innovations should: help reduce the costs of holding individual Games, significantly expand the number of candidate countries wishing to host the Olympic Games, allow small countries that currently lack the economic capacity to host the competitions; distribute the attention of fans more evenly and increase their interest in a greater number of sports disciplines by holding Olympic competitions annually; provide an opportunity to expand the list of new potential Olympic disciplines and raise the status of existing ones. Conclusion. Currently, the world is seeing an obvious decline in interest in the Olympic movement and Olympic ideas. Without making serious changes to the program of Olympic competitions, taking into account modern realities and the interests of the younger generation, there is a high risk of losing Olympism as a social phenomenon that unites nations.

Club coaches, national team coaches, as well as Olympic or Paralympic team coaches are those trainers who use their knowledge, professionalism and experience to lead their trainees to achieve sports results that satisfy athletes as well as coaches and authorities of Polish associations of various sports disciplines practiced by the athletes. A good trainer is the most important person in the coaching team, as they supervise the whole participation of their Olympians or Paralympians. Among the graduates of the Szczecin University’s Physical Education, there are many trainers of various sports disciplines. They are club coaches, national team coaches and they also hold coaching functions at the Summer Olympic and Paralympic Games. The aim of this paper is to: present the university (student) characteristics of the analyzed coaches and a physiotherapist who stand among the potential candidates to be appointed for the coaching and medical staff of their trainees (including the football team) who will fight for qualification standards guaranteeing them participation in the 32nd Summer Olympics or 16th Paralympic Games Tokyo 2020; showing the current coaching activity of the trainers and a physiotherapist in question; presenting the criteria and eligibility rules which the athletes of the coaches and the physiotherapist need to obtain to take part in the Tokyo Olympic or Paralympic competition. The research material consists of six graduates of the University of Szczecin, who majored in Physical Education, and who currently work primarily in the coaching team (Tomasz Kaźmierczak, Jacek Kostrzeba, Tomasz Lewandowski, Grzegorz Musztafaga, Milosz Stepinski) and the medical/therapeutic team (Beata Buryta). All of the analyzed graduates of the University of Szczecin are among the trainers and physiotherapists who are candidates for the Polish national team for the 32nd Olympic Games or the 16th Paralympics Games Tokyo 2020. Tomasz Kaźmierczak – he will definitely be present for the fourth time at the Summer Games Tokyo 2020 as a coach for disabled rowers (previous participations in 2008, 2012, and 2016). The trainees of the coaches in question (except for the football team) can be included into the Polish team participating in the Summer Games Tokyo 2020 and at least compete in finals during the Olympic or Paralympic competition.

To measure the energy efficiency performance and the characteristics of electronic cooling fans a high-precision suction side test rig was designed according to the corresponding national DIN and international ISO standards. To evaluate the influence of the test rig design on the precision of the performance measurements of the fan, the complete test rig designs were analyzed in detail with the commercial CFD solver Star-CCM+ from Siemens PLM Software. Since at the test rig the pressure values of the fan are measured indirectly at the test rig chamber and not at the fan itself, the pressure values from the simulation as read out at the test rig chamber and at the fan itself were compared to deliver the required precision of the test rig design. Furthermore, the effect of the baffle plate and the throttle characteristics on the energy efficiency performance measurements of fans for electronic cooling have been analyzed.

Design and performance of an electrothermal MEMS microengine capable of bi-directional motion

Symmetrical decorations enhance the attractiveness of faces and abstract designs

Both, the kinematics and the statics of the mechanical state of a solid can be represented in the language of differential geometry. If the state is defect‐free then the geometry is, in general, Riemannian. The above statements are proved for the general nonlinear case. In particular it is argued that stress function tensor and stress tensor play the role of the metric and Einstein tensor, respectively, of the stress space whereas the equilibrium conditions for forces and moments (in absence of volume forces and moments) are the Bianchi identies of the stress space. Extension to solids with defects is possible.

Field theory tools are applied to analytically study fluctuation and correlation effects in spatially extended stochastic predator–prey systems. In the mean-field rate equation approximation, the classic Lotka–Volterra model is characterized by neutral cycles in phase space, describing undamped oscillations for both predator and prey populations. In contrast, Monte Carlo simulations for stochastic two-species predator–prey reaction systems on regular lattices display complex spatio-temporal structures associated with persistent erratic population oscillations. The Doi–Peliti path integral representation of the master equation for stochastic particle interaction models is utilized to arrive at a field theory action for spatial Lotka–Volterra models in the continuum limit. In the species coexistence phase, a perturbation expansion with respect to the nonlinear predation rate is employed to demonstrate that spatial degrees of freedom and stochastic noise induce instabilities toward structure formation, and to compute the fluctuation corrections for the oscillation frequency and diffusion coefficient. The drastic downward renormalization of the frequency and the enhanced diffusivity are in excellent qualitative agreement with Monte Carlo simulation data.

During the 2012 London Olympic Summer Games, Indigenous boxer and member of the Australian national team Damien Hooper was nearly disqualified from Olympic competition for entering the ring wearing a shirt inscribed with the Aboriginal flag of Australia. National Olympic officials cited charter rule 50, which forbids political, religious, or racial demonstrations inside an Olympic venue, to immediately reprimand this Indigenous athlete for his actions. Using the Hooper example, this paper argues that Olympic principles and governing laws undoubtedly infringe on the fundamental human rights of marginalized and oppressed populations throughout the world. Specifically, Olympic Charter rule 50 categorically sustains the illegal missions of colonizing settler governments that attempt to rule over Indigenous people and their lands. Within the Olympic domain, Indigenous athletes are forced to assume the identity of the colonizing settler citizenry, thereby further validating the political authority of an illegally imposed governing structure.

In Brief: Nine elite male distance runners were evaluated by comprehensive periodic monitoring of selected blood chemistry variables, percent body fat and lean body mass, and cardiopulmonary performance as they prepared for the 1984 Olympic Summer Games in Los Angeles. The most consistent changes included a decrease in percent body fat (5.4% to 4.6%, p <.05) and an increase in anaerobic threshold. Compared with a healthy, untrained group matched for age, sex, and height, the runners showed measurable differences in resting pulmonary function, including elevated pulmonary diffusing capacity, maximum voluntary ventilation, and peak expiratory flow rate. Consistent deviations in indexes of iron stores and metabolism were also noted. The extent to which such altered iron status compromises training and competitive performance or may be restored by iron supplementation needs further investigation.

This paper describes the architecture and laboratory prototype implementation of the data handling subsystem (DHS) contributed by Team Canada to the Young Engineers' Satellite (YES2) project YES2 is a space-tether initiative of the European space agency uniting thirty universities in Europe, Canada, Asia, and Australia. The purpose of the DHS is to control a 35 km swinging tether for insertion of a low-mass payload into the Earth' s atmosphere from a low-orbiting spacecraft such as the International Space Station. Single event effects, absence of convective cooling, and tether length estimation are the primary design challenges. As a consequence, key software and hardware design features include radiation mitigation, power minimization, thermal mitigation, pulse detection and emphasis on discrete components. The DHS has recently undergone interface testing with teams from Spain, Italy, and Germany at the first YES2 test readiness review at ESTEC with launch scheduled on a Russian carrier for 2005.