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Small-bore pipes inside manifold structures are designed to be flexible. The piping must absorb thermal and pressure loading, as well as installation tolerances, well growth and in some cases stroking and/or other temporarily imposed displacement controlled conditions. Depending on well conditions and functional requirements the piping is often highly utilised statically. Vortex-induced vibrations (VIV) are on the other hand directly related to the frequency of the piping, and the more flexible a system is, the more prone it is to respond to cyclic loading induced by waves and current. Generally small-bore piping responds easily to VIV since the VIV onset flow velocity is directly proportional to the diameter. Small-bore piping have by default very small diameters, therefore the onset value for VIV is lowered compared to systems with larger diameters. In order to mitigate this environmental loading effect, it is favourable to increase the frequency of the system. Increasing the frequency is however normally done by making the system stiffer, more rigid, which generally is not desirable since this in turn increases the level of static utilisation. The current industry practice for VIV design of small-bore piping systems is to apply onset criteria. Onset criteria are in themselves applicable for small-bore systems, but they are very conservative, and DNV has in projects encountered several systems where a balance between onset of VIV and static utilisation was not obtainable. As temperatures, well growth and operational pressures increase with more complicated well conditions, the challenges with flexibility versus rigidity in small-bore piping will only increase, and previous design methodologies using typical onset criteria will be more difficult to apply successfully. There are many possible solutions to this problem; such as shielding, clever layout design, and/or direct VIV mitigation measures mounted on the pipes. This paper proposes a general methodology for advanced fatigue calculations to decrease the level of conservatism, and introduces some mitigation techniques which have been successfully applied in projects for systems where both onset criteria and fatigue utilisation criteria fail, and where fulfilling them is not possible within the confines of acceptable static utilisation.

Jumping is a natural exertion that occurs during a variety of human activities including playing sports, working, skateboarding, dancing, escaping from hazardous events, rescue activities, and many others. During jumping, the ankles in particular are expected to support the entire body weight of the jumper and that may lead to ankle injuries. Each year hundreds of patients are treated for ankle sprains/strains with ankle fractures as one of the most common injuries treated by orthopedists and podiatrists. The knee joint is also considered the most-often injured joint in the entire human body. Although the general anatomy of the lower extremities is fairly well understood, an understanding of the injury mechanism during these jumping tasks is not well understood. The aim of this study is to determine the reaction forces exerted on legs and joints due to vertical jumps, through musculoskeletal simulation and experimental studies to better understand the dynamic jump process and the injury mechanism. The joint reaction forces and moments exerted on the ankle, knee and hip joint during takeoff and extreme squat landing of a vertical jump were determined through the application of musculoskeletal simulation. It is concluded that during extreme squat landing of a vertical jump, joint reaction forces and moments were highest in proximal/distal and anteroposterior direction may cause most likely injury to the hip joint ligaments, ankle fracture and knee joint, respectively.Copyright © 2011 by ASME

Rigid subsea jumper systems are typically used as interface between subsea structures and are required to accommodate significant static and dynamic loads. Due to constraints imposed by in-line planar jumpers (e.g. U shaped and M shaped jumpers), the industry is shifting towards the use of multi-planar jumper systems (e.g., Z-shaped jumpers). These multi-planar jumper systems have increased tolerance to end displacements and can be tailored to accommodate cyclic end motions of subsea structures. Multi-planar systems, however, come with unique challenges of their own including the coupling of flexural and torsional responses under vortex induced vibrations (VIV), fluid induced vibration (FIV) and slugging. In particular, the development of hydrodynamic slug flow is a common occurrence in oil and gas pipelines. It is understood to be initiated by instabilities of wave on the gas-liquid interface. It is also understood that slug flows are the source of vibration within pipework when a change of direction occurs e.g. 90° bend at a subsea riser base or top side piping. In standard slug flow vibration analysis, averaged slug frequency and length are used to calculate the force generated. In the case of a multi-planar rigid jumper, several changes of direction occur within a short length of pipe. After each bend the characteristics of the slug flow are modified. It is necessary to accurately capture these changes in order to reproduce the forces generated at critical points along the jumper length. This paper presents a methodology for analyzing slugging induced fatigue that has been developed in an on-going study undertaken by MCS Kenny for design of multi-planar rigid jumper systems. In this methodology, Computational Fluid Dynamics (CFD) is used to accurately simulate the flow within the jumper and provide pressure fluctuations on the internal pipe wall for the vibration analysis. The pressure fluctuations are then incorporated in a Finite Element (FE) model of the jumper system and further used to determine the slugging fatigue damage. CFD (Star-ccm+) and FE (Flexcom, ABAQUS) software programs are used to accurately capture the response of the jumper system. Key conclusions and challenges overcome during the course of this study are presented herein.Copyright © 2011 by ASME

Shape Memory Alloys (SMAs) have been used for a wide variety of applications in various fields such as robotics. If these materials subjected to an appropriate thermomechanical process, they have ability to return to their initial shape. Often, they are used as actuators in robotic applications. The purpose of this paper is to present a brief review of literatures which using SMA in different robots' structure. First an introduction about shape memory effect of these materials will present. Then an assessment of done researches in application of these materials in robots' structure will accomplish and is devoted to the following area of robotics: Crawler, jumper, flower, fish, walker, medical and Biomimetic robotic hand.

It’s time to put together all you’ve learned about OpenGL ES into a game. As discussed in Chapter 3 , there are several very popular genres from which to choose when developing a game in the mobile space. For our next game, we decided to stick to the casual genre. We’ll implement a jump-’em-up game similar to Abduction or Doodle Jump. As with Mr. Nom, we’ll start by defining our game mechanics.

This paper presents a model of ski jumping movement after the take-off phase. The flight distance of ski jumping is dependent on the aerodynamic forces. We measure the aerodynamic forces using a scale model of a ski jumper for three flight styles (Normal Style, V Style, Flat V Style) and in addition measure the aerodynamic forces present after the take-off motion. The longest flight distance is achieved with Flat V Style. Considering style transition, we calculate the optimal Changing Time (CT) from Normal Style to V Style or Flat V Style to V Style with computer flight simulation. The relation between the initial angular velocity of a rigid body model of a ski jumper on the sagittal plane and flight distance is clearly explained. In the take-off phase a significant fraction of jumpers initiate upward motion by rotating the upper body. But others complete this movement with small rotation of the upper body to decrease drag. We performe computer simulations for these two cases from takeoff to 0.4sec after take-off. Linear velocity is greatly decreased with the first jumping technique. The second technique however does not suffer from this velocity decrease.

This paper proposes double-rod-type jumper horns in strain assemblies with pipe jumpers for 500-kV transmission lines, the structure of which is very simple. It can be estimated that no corona discharge appears on the horns under the line voltage of 525 kV. The arc behavior on the double-rod-type jumper horns is similar to that on the single-rod-type horns. The arc can be held stably for 60 ms against strong wind (10 m/s). The stable duration increases more than 300 ms under windless condition, therefore the horns have been adopted for practical use.

We have confirmed that terrestrial magnetism and acceleration sensors are useful to measure ski jumper’s in run descending speed and taking-off positions using a model of ski jumping ramp. Also, we gathered required measurement by inquiring a ski jumping athlete and his coach. As this result, we confirmed following measurement: in run descending speed, jumper’s style and posture at jumping point, and slant of body of the jumper when he is flying. We are developing a ski jumper’s motion monitoring system using terrestrial magnetism, acceleration sensors, and video camera which enable to monitor such measurements. In this paper, we describe its design and implementation.

The jumping procedure of the jumper in standing long jump was captured with a high-speed video camera. The geometrical configurations and motion postures of the jumper in standing long jump were analyzed from the high-speed photographs. By biological observation and kinematic analysis, the jumper jump was divided into stance phase, flight phase and land phase. Based on the observation, the jumping robot was simplified and a mechanical model was put forward. The angles of hip joint, knee joint and ankle joint were analyzed. These results would provide some theoretical and practical references for biomimetic design for improving the reasonable motion of the humanoid jumping robot. This work may provide the basic theory in developing humanoid jumping robot in structural design. Besides, it provides an important reference to study the other bionic robots.

Passive running robot can run down shallow slope with no energy source without gravity. The robot can generate a stable limit cycle. Dynamics of passive running is very interesting target and important for developing the robot and understanding the human locomotion. By the way, running high jumper can jump very high. The point of jumping is to transfer horizontal velocity into lifting momentum through the hinged-movement. In this paper, we demonstrate the experimental passive running based on the hinged-movement. Moreover, we derive the fixed point of the passive running, and analyze its stability.

Triple jumpers employ either an asymmetrical 'single-arm' action or symmetrical 'double-arm' action in the takeoff of each phase of the jump. This study investigated which technique is more beneficial in each phase using computer simulation. Kinematic data were obtained from an entire triple jump using a Vicon automatic motion capture system. A planar 13-segment torque-driven subject-specific computer simulation model was evaluated by varying torque generator activation timings using a genetic algorithm in order to match performance data. The matching produced a close agreement between simulation and performance, with differences of 3.8%, 2.7%, and 3.1% for the hop, step, and jump phases, respectively. Each phase was optimised for jump distance and an increase in jump distance beyond the matched simulations of 3.3%, 11.1%, and 8.2% was obtained for the hop, step, and jump, respectively. The optimised technique used symmetrical shoulder flexion whereas the triple jumper had used an asymmetrical arm technique. This arm action put the leg extensors into slower concentric conditions allowing greater extensor torques to be produced. The main increases in work came at the joints of the stance leg but the largest increases in angular impulse came at the shoulder joints, indicating the importance of both measures when assessing the impact of individual joint actions on changes in technique. Possible benefits of the double-arm technique include: cushioning the stance leg during impact; raising the centre of mass of the body at takeoff; facilitating an increase in kinetic energy at takeoff; allowing a re-orientation of the body during flight.

In this paper, we evaluate the performance of an FPGA-like interconnect fabric for structured ASICs which is based upon fixed metal and programmable vias. We call this type of device a via-programmed structured ASIC or VPSA. We look at two different types of VPSA routing fabrics: one uses jumper wiring and the other uses crossover wiring. The performance of these fabrics is compared against an ASIC-like interconnect fabric, otherwise known as a metal-programmed structured ASIC or MPSA, which can be configured by customizing metal and via layers. We study the impact of these routing fabrics on cost, area, power and delay metrics. The results for different fabrics span a wide range, suggesting the routing architecture plays a very important role in their overall performance and it should be thoroughly researched.

Ski jumping has continuously raised major public interest since the early 70s of the last century, mainly in Europe and Japan. The sport undergoes high-level analysis and development, among others, based on biodynamic measurements during the take-off and flight phase of the jumper. We report on a vision-based solution for such measurements that provides a full 3D trajectory of unique points on the jumper's shape. During the jump synchronized stereo images are taken by a calibrated camera system in video rate. Using methods stemming from video surveillance, the jumper is detected and localized in the individual stereo images, and learning-based deformable shape analysis identifies the jumper's silhouette. The 3D reconstruction of the trajectory takes place on standard stereo forward intersection of distinct shape points, such as helmet top or heel. In the reported study, the measurements are being verified by an independent GPS measurement mounted on top of the Jumper's helmet, synchronized to the timing of camera exposures. Preliminary estimations report an accuracy of +/-20 cm in 30 Hz imaging frequency within 40m trajectory. The system is ready for fully-automatic on-line application on ski-jumping sites that allow stereo camera views with an approximate base-distance ratio of 1:3 within the entire area of investigation.

Jumpers are typically short sections of curved pipe spanning production riser elements on the sea floor. When in areas of significant currents these jumpers are subject to vortex induced vibration (VIV). The complex shape of the jumper means that numerical methods are usually needed to solve for the vibration modes of the jumper. Furthermore, the fluid flow around the jumper is also complex so that traditional methods of VIV analysis used for risers are not applicable to jumpers. Here we use a CFD code in a fully coupled analysis to predict vibration response and strain of a typical subsea jumper. A separate finite element analysis is used to calculate the eigenvalues and eigenvectors of the jumper system for input into the CFD analysis. The resulting method is economical and practical for design analyses.Copyright © 2010 by ASME

This paper presents the results of a test to analyze the performance of implosive connectors on ACSS (Aluminum Conductor Steel Supported) conductor in a high-temperature environment. A 500-cycle high-temperature current cycle test at 250°C above ambient temperature was carried out on ACSS 1,113 kcmil Finch conductor using implosive full tension joint, dead end and jumper terminal connectors. A total of 15 connectors was tested. This paper discusses the methodology used and presents the results observed. The positive results of this test support the use of implosive connectors in high temperature applications and provided the rationale for continuing the test for an additional 500 cycles for a total of 1000 cycles, the results of which will be reported in a future paper

As VLSI technology advances to smaller technology nodes, the antenna effect has become a critical issue in the yield and reliability of the VLSI circuit, especially for analog ICs. Jumper insertion is an effective technique to fix the antenna effect. Traditional works on antenna fixing are mainly for digital ICs rather than analog ICs. This paper presents heuristic algorithms for jumper insertion during routing for analog ICs, which handles the expansion limitation of different types of nets, such as general nets and matching nets, and reexamines the matching parameters of matching nets after jumper insertion. The experimental results show the effectiveness of our algorithms.

As oil/gas field developments move further away from existing subsea structures, it becomes advantageous to consider subsea tie-ins of their export systems with existing deepwater pipeline systems that offer spare transport capacity. This necessitates incorporating pipeline end manifolds (PLEMs) at both pipeline ends to tie in the system. A PLEM is a subsea structure set at the end of pipeline that is used to connect a rigid pipeline with other subsea structures, such as manifolds or trees, through a jumper. It is also called a pipeline end termination (PLET), especially when serving as a support for one pipeline valve and one vertical connector. The purpose of the PLEM is to provide an installation structure to attach these piping components and then lower them to the seafloor in the desired orientation. The structure must not only withstand the installation loads while being lowered to the seafloor, but also retrieval to the surface should a failure occur. The PLEM foundation provides support for the structural frame of the piping system. In addition to their normal functions, PLEMs are designed to accommodate reasonable thermal expansion of the pipeline during operation.

This paper will describe the first use of a retrofit non-intrusive pressure measurement system to monitor effects of remediating a hydrate blockage in a deep-water flowline jumper. The system was developed in response to a requirement to monitor pressure on the jumper in order to aid in gas hydrate remediation and to monitor the effects of the remediation processes to clear the blockage. An ROV-deployed non-intrusive hoop strain monitoring system (subC-pts*) was designed for clamping to the flowline, which had unknown internal pressure distribution, in order to report hoop strain changes, therefore derive the internal pipe pressure during intervention and remediation. In addition to the requirement for permanent storage of data, Schlumberger’s design included a high intensity LED mounted in the wall of unit, indicating the value of hoop strain on the subC-pts. Four self-contained systems were supplied. Each stand-alone sensor comprised an optical interrogation system, battery pack, data storage and real-time LED. The subsea optoelectronics were contained in a pressure-sealed housing secured to a composite structure containing fiber-optic strain sensors. The housing was removable from the sensor unit, for maintenance purposes, and was connected to the composite structure by an optical jumper cable. The systems were ROV-deployed onto a 30m length of jumper, at depths greater than 1000m. The measurement of hoop strain using highly linear strain sensors, and the deduction of pressure variation is examined. Focus is given to the novel aspects of the technology, and to areas where further improvements can be made, particularly with a view to developing alternative potential problem solving applications.Copyright © 2010 by ASME

The free standing hybrid riser (FSHR) offers advantages over other field proven deepwater riser concepts for particular applications and has been used mostly off West of Africa. This concept has evolved in the last few years and now is drawing more attention in other deepwater provinces worldwide, such as the Campos Basin in Brazil and the Gulf of Mexico (GoM). It is basically a combination of steel and flexible risers with utilization of their advantages and hence offers unique features. This paper presents the engineering design and analysis aspects of deepwater FSHRs including key technologies and techniques. First of all, a general description and comparison of the FSHR system is presented. Secondly, the logical procedure for design and analysis of deepwater FSHRs is discussed and presented in more detail. Due to the complexity of FSHRs, different applicable design codes have been presented and discussed. Global configuration design with consideration of riser performance and its effect on component design is presented followed by major design considerations for individual components of the system. Thirdly, the analysis requirement and methodology is discussed in detail with focus on global response analysis, vortex induced vibration (VIV) analysis, buoyancy can (BC) VIM fatigue analysis, interface loads, and component analysis such as buoyancy can, tether chain system, top riser assembly, flexible jumper configuration, and riser base pile. The relationship between engineering design, fabrication and installation, which is of particular interests to this type of riser, is briefly discussed.Copyright © 2010 by ASME

The long jump is one of the most natural events in track and field athletics. The jumper is allowed to run a 40-m runway at top speed and jump as far as possible from a takeoff board. It is an event in which the natural ability of the athlete plays a large role and technique is of secondary importance. The two most important factors in the long jump are speed and elevation.

With the increasing popularity of freestyle skiing and snowboarding many ski resorts constructed their own terrain parks including several jumps, rails, and pipes. In order to prevent risks of high-impact injuries in jumping, an adequate construction of the landing hill is very important. In professional ski jumping this can be achieved by designing the landing area profile so that its curvature follows the flight path of the jumping athlete. Classical kicker shapes do not follow this principle. They consist of a ramp subsequently followed by a flat table and a descending landing area. Construction of these kickers is commonly made by trial and error. To make the construction process safer and reduce unnecessary risks, a guideline for save kicker construction based on multiple simplifications of the real situation was published in the literature. The purpose of this study was to investigate how this guideline applies to the situation in a real kicker. Two skiers and three snowboarders performed a total of eleven jumps on one expert’s kicker (table length 17 m, transition angle 20°, and kick-off height 2.5 m). Computer simulations, based on the take-off velocities of the eleven jumps measured, were used to calculate the impact energy during landing on different table lengths combined with different landing slopes. If the jumper fails to adjust take-off velocity to account for the shorter deck length, the sum of the impact energies of the simulated jumps will increase dramatically at table lengths smaller than 15 m combined with a landing steepness greater than 20. The predictions based on the guideline (16 m table length and 33° landing steepness) are within a safe region. The guideline is therefore applicable for the experts kicker investigated.

We have been developing a monitor system of workers in a factory using terrestrial magnetism sensors and acceleration sensors. Terrestrial magnetism sensor is not suitable to monitor linear movement, however, we confirmed it can monitor rotation movement in very high accuracy. Sport is a new possible application area for this system. Terrestrial magnetism sensor is not suitable for sports that player moves about such as soccer, however, it is suitable for sports that require stable forms such as pitching form of baseball, swinging on golf, it is thought. In this paper, we discussed a possibility to apply terrestrial magnetism sensor based monitoring system into ski jumping which seem to be one of sports which require stable forms to athlete. As a result of preliminary evaluation to measure descending speed, and position of taking off, we confirmed high possibility to apply terrestrial magnetism sensor based monitoring system into ski jumping.

This paper calculated the potential and electric field distribution of cage-type rigid jumper for strain towers used in 1000kV UHV transmission lines by finite element method. The electric field distrubution on the surface of jumpers and fittings, the electric field distribution curves along jumpers were simulated and analyzed. Based on the results, the general characteristics of electric field distribution for rigid jumpers were proposed. Finally, some suggestions were given to improve the electric field distribution on the surfaces of jumpers and fittings. The conclusions given by this paper have important engineering application value for the UHV transmission lines construction.

Background The onset of jumper's knee is generally associated with sports and sporting activities. Employees in certain professions might be at risk as well for developing jumper's knee. Therefore, it is of interest to identify risk factors in sport and/or occupation. Findings A systematic search of the international scientific literature was performed until November 2008 in the scientific databases (a) Medline, (b) Embase, and (c) SportDiscus. All types of studies were included. The search strategy retrieved ten articles about risk factors in sport that met the inclusion criteria. Risk factors that could be identified are; playing volleyball (4 studies), playing basketball (3 studies), training and playing volleyball/basketball more than 12 hours per week (2 studies), in combination with weight-bearing activities of at least 5 hours per week (1 study) and playing or training on a hard surface (1 study). No studies were found regarding occupation that fulfilled the inclusion criteria. Conclusion Playing volleyball and basketball has a positive association with the onset or worsening of jumper's knee. Other risk factors are training and playing hours of at least 12 hours per week and/or in combination with weight training of at least 5 hours per week, and/or with playing or training on a hard surface. We did not find a specific occupational risk factor.

Ski jumping puts high demands on the athlete's ability to control posture and movement. The athlete has to solve extremely difficult optimization problems. These implicit decisions and the resulting control manoeuvres can be understood by means of computer simulations. Computer simulations based on wind tunnel input data can identify the determinants for high performance and answer many questions of training methods, safety and health, role of weight, fairness, optimized hill design, sport development, and changes to the regulations. Each of the performance determinants has to be seen in the context of all others in order to understand its importance; the predominant factors are: high in-run velocity, high momentum perpendicular to the ramp at take-off due to the jump and the lift force, accurate timing of the take-off with respect to the ramp edge, appropriate angular momentum at take-off in order to obtain an aerodynamically advantageous and stable flight position as soon as possible, choice of advantageous body and equipment configurations during the entire flight in order to obtain optimum lift and drag values, and the ability to control the flight stability. Wind blowing up the hill increases the jump length dramatically and decreases the landing velocity, which eases the landing, and vice versa for wind from behind. Improvements to reduce unfairness due to changing wind are urgently needed. The current practice of the judges to reduce the score when the athlete has to perform body movements in order to counteract dangerous gusts is irrational. The athletes should rather be rewarded and not punished for their ability to handle such dangerous situations. For the quantification of underweight it is suggested to use the mass index: MI=0.28 m/s2 (where m is the jumper mass and s is the sitting height), which indirectly considers the individual leg length. The MI formula is similar to the body mass index (BMI) formula: the height is replaced by the sitting height s and a factor of 0.28 effects that the MI is equal to the BMI for persons with average leg length. The classification of underweight is not only a question of the cut-off point, as much it is a question of the measure for relative bodyweight used. Low weight is one of the performance determinants; however, it should be considered that very low weight can cause severe performance setbacks due to decreased jumping force, general weakness, reduced ability to cope with pressure, and increased susceptibility for diseases. In the past, several cases of anorexia nervosa among ski jumpers had come to light. The development toward extremely low weight was stopped in 2004 by new Federation Internationale de Ski ski-jumping regulations, which relate relative body mass to maximum ski length. The 2006/7 and 2008/9 seasons showed that light athletes who had to use skis with just 142% of their height could still win competitions. A further increase of the borderline weight is being discussed. The current regulations are based on the well known BMI; the use of the MI instead of the BMI should be explored in future studies.

Numerical analyses have been performed on a generic ski jumper in flight based on Computational Fluid Dynamics (CFD) flow codes and a geometric simulation of the jumper with skis. Various configurations have been simulated and results are presented for several body/ski positions and flight angles. A theoretical analysis of the performance of the ski jumper is also briefly presented. In addition, a proposal for new jumping skis design is described as an outcome from the present numerical analysis.

Recently Aoi et al.[1] reported unusual results for the surface acceleration of the KiK-net IWTH25 station in response to the 14 June 2008 Iwate-Miyagi mainshock, moment mag- nitude 6.9. Accelerations as large as 4g were observed with the acceleration waveform showing distinctive asymmetry, i.e., large, positive accelerations of short duration were bal- anced by small, negative accelerations of long duration. These observations prompted the sobriquet trampoline effect for it seemed that the earth surface was moving much like a jumper on a trampoline. To understand what is going on we undertake examination of the IWTH25 station data sets and introduce a model for what is seen. Examination of the data at the IWTH25 station show the asymmetric vertical acceleration (initially noted by Aoi et al.[1]) and most importantly strong correlation between vertical mo- tion and horizontal motion. A lumped element model[2] for this system, involving nonlinear surface-subsurface coupling, is introduced and shown to have...

The paper discusses the results of wind tunnel tests for different angular configurations (φ1 and φ2) of a V-style (Graf–Boklev style) ski jumper model. The range of tested angles of attack was α = –10, 20, 30, 40 (deg), depending on a configuration. The configurations of the Graf–Boklev style ski jumper model were compared with the classic parallel style of ski jumping with the ski-opening angle λ = 0. Kl as a configuration for the parallel style of ski jumping was used as the reference configuration for other configurations with different ski-opening angles, i.e. λ = 0, 15, 25, 45 (deg). The results obtained have been presented graphically as aerodynamic parameters within a specific angle of attack.

In this paper a method is presented for connectively analyzing the dynamic factors in physical training by utilizing computers. Through analyzing the training results of a certain triple jumper, the thesis expounds how to build the mathematics models for the connective factors in system and it also presents the detailed procedure by utilizing these models to connectively analyze the dynamic changes of the factors in system. It will supply a scientific method for the staff who is engaged in physical teaching and training by utilizing computers to do the researching and managing work in physical training.

As the offshore industry continues to progress developments in deep and ultra-deep water locations, in many large EPCI contracts (Engineering, Procurement, construction and Installation) the considered or preferred riser system solutions are steel catenary risers (SCRs) or lazy wave (LW) SCRs. The criticality of SCR technology continues to require detailed assessment of technology risks for each specific development, even where design conditions may not appear to vary significantly from previous developments. The potential for increased water depth, severity/complexity of environmental loading, a wider range of vessel typology and with ongoing integrity monitoring & maintenance feedback, it is clear that there is an increasing risk that SCR will exceed the technological limits for near future developments. Looking forward, there is a primary need to manage the risks of this elegant & commercially attractive riser solution by ensuring the margin between the expected fatigue /extreme loading and the current technological limits of metallic material/welding, top connection and non-metallic components. In this context, and through a fully integrated approach to riser technology, SAIPEM has conceived and matured families of hybrid riser systems based on field proven technology. One of these families is the novel hybrid riser family, specifically conceived to extend the application of SCR & LWSCR in a cost effective way as well as offering certain additional improvements. The basic solution is the RCS (Novel Hybrid Riser with Top Connecting Arm & Shallow Water Jumper); a balanced cost /risk hybrid riser solution to compete with SCR & LWSCR. RCS offers consistent improvements and is adaptable to the major vessel typologies, from semi-subs to disconnectable turret moored FPSOs. The RCS comprises Top Connecting Arm (TCA), Riser Top Assembly (RTA) and Tension Restrained Jumper (TRJ) or simple short/long catenary jumper (SCJ), and is connected to the vessel by means of a deepwater type mooring connector. RCS+ is a further evolution of RCS incorporating adjustable length TCA. RCS+ Heave Motion Damper (HMD) is a future evolution of RCS, and is described separately. The RCS is an example of the application of an industrial model that includes an integrated engineering and execution expertise to achieve future cost effective solutions.

We measured the effects of MPI for systems that include Fabry-Perot lasers and short bend insensitive fibers and analyzed contributions from different factors including both laser and fiber characteristics.

Based on the results of several different experiments, it has been concluded that the weight of a ski jumper is crucial in performing a long ski jump. In response to this conclusion, many of the best ski jumpers in the world began dieting to reduce their weight, resulting in many underweight athletes and some incidents of anorexia. In order to deal with this problem the International Ski Federation (FIS) introduced a new rule where the ski length is determined by both the jumper’s height and weight. An athlete with a Body Mass Index (BMI) of less than 20 must reduce the length of his or her skis.

A free standing hybrid riser (FSHR) is a proven solution for deepwater floating production systems. In this system, a submerged buoyancy can supports and tensions a vertical riser. The riser top is connected to a floating production system through a flexible jumper. The FSHR has been used in West Africa and Brazil and will be put into application in the Gulf of Mexico. Experimental and analytical efforts are continuing to better understand the vortex-induced vibration (VIV) response of this riser system. This paper presents a comparison of experimental and numerical results of the VIV response of a FSHR. The analysis is performed with a time domain VIV code ABAVIV, which uses the finite element software package ABAQUS to calculate the response from the VIV forcing. Unlike frequency domain VIV codes, ABAVIV captures structural nonlinearities and the transient nature of the VIV phenomenon. Comparisons between numerical and experimental results for buoyancy can VIV response and loading at the bottom of the riser are presented and show generally good agreement. The relative contributions of buoyancy can and riser VIV to the overall system response are investigated. The paper will also include calculated VIV response from frequency domain methods.Copyright © 2009 by ASME

PETROBRAS has been developing several studies in order to verify the structural feasibility of SCRs connected to production units such as FPSOs, semi-submersible and monocolumn platforms. Due to the great stresses developed at the top region as a consequence of the platforms rotation movements, robust stress joints or flex joints are always required to connect the SCRs to the platforms. However, those components may add high costs to any project, mainly where titanium is required. In attempt to avoid this fact, the objective of this work is to present a new top connection system called “Suspender”. This system is composed by the SCR, a mooring line segment, a flexible jumper and a “Y” shaped steel connector, and has the advantage of reducing the transmission of bending moments from the platform to the SCR. The performance of this alternative was compared to a more conventional one, composed by a SCR and a flex joint, and the obtained results indicate that this new system reduces the maximum stresses at the top region without changing the SCR behavior at the TDZ. It is also possible to extend the fatigue life by changing the SCR configuration.Copyright © 2009 by ASME

The effectiveness of recovery of fibres by taping has been investigated using three types of fibre from three donor garments and three types of recipient garment. Results showed that, on the majority of occasions, less than 50% of transferred fibres which were present on the garment after 8 h of wear were recovered from a wool jumper and an acrylic jumper. Percentage recovery did, however, vary widely. Use of greater quantities of tape did not improve the level of recovery. Fibres were recovered most effectively from the smooth surface of a polyester jacket though few fibres remained on the garment after 8 h of wear. Cotton fibres remaining on recipient garments tended to be short and were recovered more efficiently than wool and acrylic fibres. The majority of all three types of transferred fibres remaining on garments after 8 h were less than 2 mm in length. The main parameters affecting efficiency of recovery appear to be the type of recipient surface and the type of transferred fibre. These results emphasize that, in some circumstances, low effectiveness of recovery must be taken into account when interpreting the numbers of fibres actually found in casework.

A perturbation model is used to predict the distance jumped by a long-jumper for a range of tailwinds and headwinds. The zeroth-order approximation is based on gravity being the only force present, the effects of drag and lift only being included in the first-order corrections. The difference in predicted distances produced by the zeroth and first-order approximations is less than 2% for headwinds or tailwinds upto 4 ms−1. Most increases or decreases due to wind are caused by changes in the run-up speed, and consequently the take-off angle and speed.

Jumper's knee, or patellar tendinopathy, affects nearly one half of elite volleyball athletes and causes significant morbidity. The diagnosis and treatment of jumper's knee is evolving with heavier reliance on the use of diagnostic ultrasound with and without color or power Doppler. Research suggests that conservative treatment is very effective using an eccentric exercise regimen and decline squats. Interventional treatments are expanding as well, with positive results seen using extracorporeal shock wave therapy and polidocanol sclerosing injections. Arthroscopic surgical approaches are being developed, some using intra-operative ultrasound guidance. The findings of several recent basic science studies imply that the future may lie in developing a greater understanding of, and then possibly modulating the balance of, the local neuronal, vascular, or biochemical factors associated with symptomatic patellar tendinopathy.

BackgroundPatellar tendinopathy (jumper's knee) is characterized by localized tenderness of the patellar tendon at its origin on the inferior pole of the patella and a characteristic increase in signal intensity on magnetic resonance imaging at this location. However, it is unclear why the lesion typically occurs in this area of the patellar tendon as surface strain gauge studies of the patellar tendon through the range of motion have produced conflicting results.HypothesisThe predicted patellar tendon strains that occur as a result of the tendon loads and patella-patellar tendon angles (PPTAs) experienced during a jump landing will be significantly increased in the area of the patellar tendon associated with patellar tendinopathy.Study DesignDescriptive laboratory study.MethodsA 2-dimensional, computational, finite element model of the patella-patellar tendon complex was developed using anatomic measurements taken from lateral radiographs of a normal knee. The patella was modeled with plane strain rigid elements, and the patellar tendon was modeled with 8-node plane strain elements with neo-Hookean material properties. A tie constraint was used to join the patellar tendon and patella. Patella-patellar tendon angles corresponding to knee flexion angles between 0° and 60° and patellar tendon strains ranging from 5% to 15% were used as input variables into the computational model. To determine if the location of increased strain predicted by the computational model could produce isolated tendon fascicle damage in that same area, 5 human cadaveric patella-patellar tendon-tibia specimens were loaded under conditions predicted by the model to significantly increase localized tendon strain. Pre- and posttesting ultrasound images of the patella–patellar tendon specimens were obtained to document the location of any injured fascicles.ResultsLocalized tendon strain at the classic location of the jumper's knee lesion was found to increase in association with an increase in the magnitude of applied patellar tendon strain and a decrease in the PPTA. The principal stresses and strains predicted by the model for this localized area were tensile and not compressive in nature. Applying the tendon strain conditions and PPTA predicted by the model to significantly increase localized strain resulted in disruption of tendon fascicles in 3 of the 5 cadaveric specimens at the classic location of the patellar tendinopathy lesion.ConclusionThe localized increase in patellar tendon strain that occurs in response to the application of tendon loads and decreased PPTA could induce microdamage at the classic location of the jumper's knee lesion.Clinical RelevanceThe association of decreasing PPTA with increasing localized tendon strain would implicate the role of knee-joint angle as well as tendon force in the etiopathogenesis of jumper's knee.

Surviving in a diverse environment requires corresponding organism responses. At the cellular level, such adjustment relies on the transcription factors (TFs) which must rapidly find their target sequences amidst a vast amount of non-relevant sequences on DNA molecules. Whether these transcription factors locate their target sites through a 1D or 3D pathway is still a matter of speculation. It has been suggested that the optimum search time is when the protein equally shares its search time between 1D and 3D diffusions. In this paper, we study the above problem using a Monte Carlo simulation by considering a very simple physical model. A 1D strip, representing a DNA, with a number of low affinity sites, corresponding to non-target sites, and high affinity sites, corresponding to target sites, is considered and later extended to a 2D strip. We study the 1D and 3D exploration pathways, and combinations of the two modes by considering three different types of molecules: a walker that randomly walks along the strip with no dissociation; a jumper that represents dissociation and then re-association of a TF with the strip at later time at a distant site; and a hopper that is similar to the jumper but it dissociates and then re-associates at a faster rate than the jumper. We analyze the final probability distribution of molecules for each case and find that TFs can locate their targets fast enough even if they spend 15% of their search time diffusing freely in the solution. This indeed agrees with recent experimental results obtained by Elf et al. 2007 and is in contrast with theoretical expectation., Comment: 24 pages, 9 figures

Changing mass phenomena, like a falling chain or a bungee jumper, might give surprising results, even for experienced physicists. They have resulted in hot discussions in journals, in which for instance Physics professors claim the impossibility of an acceleration larger then g in case of a bungee jumper. These phenomena are also interesting as topics for challenging student projects, and used as such by Dutch high school students. I will take these phenomena as the context in which I like to demonstrate the possibilities of ICT in the learning process of physics. Especially dynamical modeling enables us to describe these phenomena in an elegant way and with knowledge of high school mathematics. Furthermore tools for video‐analysis and data from measurements with sensors allow us to study the phenomena in experiments. This example demonstrates the level of implementation of ICT in Physics Education in The Netherlands [1].

The computer model of ski jumping described here considers the changing flight postures of the athlete. It is based on sets of wind tunnel data associated with the changing postures of the athlete during the flight. The computer modelling approach allows studying the impact of all variables, parameters, and initial conditions which determine the flight path — and thus the jump length — of a ski jumper. In addition, wind u (wind vector) in the vertical plane can be selected with any direction and speed. Insertion of the construction parameters of a given hill allows calculating jump lengths and also the landing impact (component of the moment perpendicular to the landing slope) as a function of jump length for the particular hill. The model enables the calculation of the flight path; the inverse approach starts out from flight path data and results in the time-funtions of the lift of drag forces and areas which can be used for a quantitative flight analysis.

The purpose of this paper is to present a method that has been developed to identify if vortex induced vibration (VIV) occurs in well jumper systems. Moreover, a method has been developed to determine when VIV mitigation measures such as strakes are required. The method involves determining the in-plane and out-of-plane natural frequencies and mode shapes. The natural frequencies are then used, in conjunction with the maximum bottom current expected at a given location to determine if suppression is required. The natural frequency of a jumper system is a function of many variables, e.g. span length, leg height, pipe diameter and thickness, buoyancy placement, buoyancy uplift, buoyancy OD, insulation thickness, and contents of the jumper. The suppression requirement is based upon calculating a lower bound lock-in current speed based upon an assumed velocity bandwidth centered about the lock-in current. The out-of-plane VIV cross-flow response is produced by a current in the plane of the jumper; whereas the in-plane VIV cross-flow response is produced by the out-of-plane current. Typically, the out-of-plane natural frequency is smaller than the in-plane natural frequency. Jumpers with small spans have higher natural frequencies; thus small span jumpers may require no suppression or suppression on the vertical legs. Whereas, larger span jumpers may require no suppression, suppression on the vertical legs or suppression on all the legs. The span of jumper systems (i.e. production, water injection, gas lift/injection ...) may vary in one given field; it has become apparent that not all jumper systems require suppression. This technique has allowed us to recognize when certain legs of a given jumper system may require suppression, thus leading to a jumper design whose safety is not compromised while in the production mode, as well as minimizing downtime and identifying potential savings from probable fatigue failures.Copyright © 2008 by ASME

Aerodynamic forces, drag and lift were estimated by the body attached inertia sensors and high speed videography in ski jumping. Last ISEA conference, the authors presented our new method for the aerodynamic study on ski jumping. In this paper, we propose more robust and reliable measurement system by using wireless technology. Wireless 6DOF inertia sensor platform, which has a built-in tri-axial accelerometer and three single axial gyroscopes, was attached on the jumper’s low back. The authors adopted IEEE802.15.4 for the start trigger and real time monitoring during long training session. Sensor also has a flush memory inside for one hour data storage at 250Hz. The primary target of the present study is to extract the aerodynamic force data during real jumping flight. Angular velocity on the sagittal plane was directly measured from the gyroscope. Then we could obtain the jumper’s body pitch angle by its time integration. The accelerations with respect to the body local coordinate system which was determined by the body pitch angle, indicated the drag and lift forces. The assessment of the aerodynamic forces of ski jumping was examined by both of the sensor data and the kinematical data in this study.

It is difficult to ascertain for an individual high jumper the optimum values of the horizontal velocity and height of the center of mass at the end of the approach ran (VHO and H0, respectively) and of the activeness of the arms during the takeoff phase (AACT), because they depend on each athlete’s ability to resist buckling of the takeoff leg. However, the strongest jumpers will generally be those with the largest vertical elocity values at the end of the takeoff phase (VZ1). Therefore, VZ1 may serve as a rough indicator of a high jumper’s ability to resist buckling. This project derived equations that permit the use of the measured VZ1 value of a high jumper to predict what values should be expected for VHO, H0, and AACT. Comparison of the predicted and actual values of these parameters should help to diagnose the technique deficiencies of individual jumpers.

Modern electronics allow for the unobtrusive measurement of accelerations outside the laboratory using wireless sensor nodes. The ability to accurately measure joint accelerations under unrestricted conditions, and to correlate them with jump height and landing force, could provide important data to better understand joint mechanics subject to real-life conditions. This study investigates the correlation between peak vertical ground reaction forces, as measured by a force plate, and tibial axial accelerations during free vertical jumping. The jump heights calculated from force-plate data and accelerometer measurements are also compared. For six male subjects participating in this study, the average coefficient of determination between peak ground reaction force and peak tibial axial acceleration is found to be 0.81. The coefficient of determination between jump height calculated using force plate and accelerometer data is 0.88. Data show that the landing forces could be as high as 8 body weights of the jumper. The measured peak tibial accelerations ranged up to 42 g. Jump heights calculated from force plate and accelerometer sensors data differed by less than 2.5 cm. It is found that both impact accelerations and landing forces are only weakly correlated with jump height (the average coefficient of determination is 0.12). This study shows that unobtrusive accelerometers can be used to determine the ground reaction forces experienced in a jump landing. Whereas the device also permitted an accurate determination of jump height, there was no correlation between peak ground reaction force and jump height.

ITER Central Solenoid uses butt joints for connecting the pancakes in the CS module. The principles of the butt joining of the CICC were developed by the JAPT during CSMC project. The difference between the CSMC butt joint and the CS butt joint is that the CS butt joint is an in-line joint, while the CSMC is a double joint through a hairpin jumper. The CS butt joint has to carry the hoop load. The straight length of the joint is only 320 mm, and the vacuum chamber around the joint has to have a split in the clamp shell. These requirements are challenging. Fig.1 presents a CSMC joint, and Fig.2 shows a CS butt joint. The butt joint procedure was verified and demonstrated. The tool is capable of achieving all specified parameters. The vacuum in the end was a little higher than the target, which is not critical and readily correctable. We consider, tentatively that the procedure is established. Unexpectedly, we discover significant temperature nonuniformity in the joint cross section, which is not formally a violation of the specs, but is a point of concern. All testing parameters are recorded for QA purposes. We plan to modify the buttmore » joining tool to improve its convenience of operation and provide all features necessary for production of butt joints by qualified personnel.« less