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Objective: To identify the skeletal, dentoalveolar, and soft tissue changes that occur during Class II correction with the Cantilever Bite Jumper (CBJ). Materials and Methods: This prospective cephalometric study was conducted on 26 subjects with Class II division 1 malocclusion treated with the CBJ appliance. A comparison was made with 26 untreated subjects with Class II malocclusion. Lateral head films from before and after CBJ therapy were analyzed through conventional cephalometric and Johnston analyses. Results: Class II correction was accomplished by means of 2.9 mm apical base change, 1.5 mm distal movement of the maxillary molars, and 1.1 mm mesial movement of the mandibular molars. The CBJ exhibited good control of the vertical dimension. The main side effect of the CBJ is that the vertical force vectors of the telescope act as lever arms and can produce mesial tipping of the mandibular molars. Conclusions: The Cantilever Bite Jumper corrects Class II malocclusions with similar percentages of skeletal and dentoalveolar effects. (Angle Orthod. 2009:79; )

Objective: The aetiology of patellar tendinopathy ( jumper's knee) remains unclear. To see whether landing strategy might be a risk factor for the development of this injury, this study examined whether landing dynamics from drop jumps differed among healthy volleyball players ( CON) and volleyball players with a jumper's knee. The patients with jumper's knee were divided into an asymptomatic group with a previous jumper's knee (PJK) and a symptomatic group with a recent jumper's knee (RJK).Methods: Inverse dynamics analyses were used to estimate lower extremity joint dynamics from 30, 50 and 70 cm drop jumps in the three groups ( CON, n = 8; PJK, n = 7; RJK, n = 9). A univariate repeated measures analysis of variance was used to compare the different landing techniques.Results: Data analysis of the landing dynamics revealed that PJK showed higher knee angular velocities ( p Conclusion: Where RJK used a landing technique to avoid high patellar tendon loading, PJK used a stiffer landing strategy, which may be a risk factor in the development of patellar tendinopathy.

A series of experimental investigations were conducted in an attempt to better understand the pilot parachute hesitation issue occurring during Military Free Fall operations. The experiments were conducted in two parts initially using the Santos Matos Vertical Wind Tunnel in Ft. Bragg, NC, to recreate the pilot parachute hesitation using freefall certified parachutists. Throughout these experiments several different factors were variedincluding wind speed, pilot parachute system, and equipment configuration. The drag force on the pilot parachute was also measured. Deployments were recorded using a video camera in order to later distinguish clean pilot parachute launches from partial and full hesitation incidents. The measured pilot parachute opening force was later related to these observations. Results showed that both pilot parachute system and equipment configuration are correlated with deployment hesitation. Higher opening force measurements also showed a decrease in hesitation. A second set of experiments were conducted to characterize the flow field around the parachutist prior to deployment of the pilot parachute. These experiments were conducted using a small-scale model of a parachutist in a MFF position. Different equipment configurations were examined and the results showed that the wake formed behind the jumper is significantly depending on equipment placement but these configurations had little effect on the drag coefficient of the jumper or the dependency on angle of attack.

Our society places great importance on a citizen's right of self-determination. One of the most obvious opportunities to exercise autonomy is when a person is able to make an informed choice concerning their medical treatment. The legal doctrine of consent ensures that people are put into a position where they can make an informed choice. Choices can be informed only if the chooser has a clear and accurate understanding of what the ‘procedure’ entails, together with its benefits, risks, complications and alternatives. In a bungee jump, the ‘procedure’ entails the opposition of gravity by an elastic band. The benefit is that the jumper may have enjoyed the experience. The risks include a rebound into the bridge from which he was suspended, or hitting the ground. The complications are, therefore, self-evident. Given the simplicity of both the procedure and its potential outcomes, there is unlikely to be a significant gap in the knowledge base between the jumper and the purveyor of the jump. The bungee jump can be distinguished from the consent for surgery. The relationship between jumper and purveyor is quite different than between patient and surgeon. Additionally, there is significant inequality between the knowledge of the patient and surgeon, and the matters to be communicated and understood by the patient are infinitely more complex. Unlike the jumper, the patient who consults a surgeon acquired their problem involuntarily, and it is one that may fundamentally affect their health. The problem may be serious, possibly endangering life. If he or she wishes to remain healthy, the patient must, therefore, acquiesce to surgery – there is effectively no choice in the matter; however, the jumper can simply walk away, and decide upon an alternative entertainment. The inevitability of the need for treatment gives the surgeon a degree of control over the patient far removed from that enjoyed by a purveyor of bungee jumps, yet Fong and colleagues try and persuade us that we should act in the manner of the latter. I am honestly unable to decide whether Fong and colleagues are simply pulling my leg. The point of my article was to point out that good consent is simply good medicine, and that the lawyers are merely peripheral players. Litigation is clearly deeply unpleasant, and something that all surgeons wish to avoid. But litigation is still only a sideshow; our main purpose is to treat our patients properly, and the law provides some, albeit incomplete, guidance on how this may be achieved. The reader will decide whether I have over-reacted to Fong et al. If they were suggesting that it is acceptable merely to place a conditional offer in front of the patient in a take-it-or-leave-it manner, then I would strongly disagree. This is incompatible with our moral duty to do the best for our patients.

In previous study, a pounding tuned mass damper (PTMD) was proposed to reduce the undesired vibration of a subsea jumper. Both experimental and numerical results verified the effectiveness of the PTMD. This paper aims to enhance the understanding of the PTMD through a parametric study. The jumper is subjected to sinusoidal forces of different frequencies. The reduction ratio is defined for evaluation of the mitigation performance. Three parameters are considered in this study: the pounding stiffness, the gap between the delimiter and the mass block, and the mass ratio. The parametric studies show that the PTMD system is not so sensitive to the small variations of the pounding stiffness and the gap. The reduction ratio is significantly increased with the mass ratio increased up to 2%. Afterwards, it is not so economic or practically feasible to enlarge the mass ratio.

A previous study by the authors proposed a new type of damper, the pounding tuned mass damper (PTMD), which uses the impact of a tuned mass with viscoelastic materials to effectively dissipate vibration energy, for structural vibration control. However, the control performance is unknown if the PTMD is not tuned to the targeted frequency of the primary structure. This paper aims to study the robustness of the PTMD against the detuning effect both numerically and experimentally. The control object was chosen as a subsea jumper, which is a flexible M-shaped pipeline structure commonly used in offshore oil and gas production. In this paper, a 15.2 m (50 feet) long jumper incorporated with a PTMD was set up. To enable the numerical study, the equation of motion of the jumper along with the PTMD was derived. Three testing cases were numerically studied: free vibration, forced vibration and forced vibration with varied frequencies. In all cases, the PTMD can effectively suppress the structural vibration when the natural frequency was off-tuned. Furthermore, experimental studies were conducted. The experimental results also implied the robustness of the proposed PTMD.

This article uses the principle of Wavelet transformation and Quad-tree structure to find the best jumper points of embroidery machine. Embroidery want the image to be cut into four equal parts. Furthermore, to judge each part if there exist two object for connection jumper point selection. For special case, the four parts divided will be extended until the best jumper point were found. According to the simulation results, our method is evidently an effective and high quality method for sewing machine for embroidering purpose.

This study used a computer simulation model to investigate various considerations that affect optimum peak height in a running jump. A planar eight-segment computer simulation model with extensor and flexor torque generators at five joints was formulated and customised to an elite male high jumper. A simulation was matched to a recorded high jumping performance by varying the activation profiles of each of the torque generators giving a simulated peak height of 1.99 m compared to the recorded performance of 2.01 m. In order to maximise the peak height reached by the mass centre in the flight phase, the activation profiles were varied, keeping the same initial conditions as in the matching simulation. Optimisations were carried out without any constraints, with constraints on the angular momentum at take-off, with further constraints on joint angles, and with additional requirements of robustness to perturbations of activation timings. A peak height of 2.37 m was achieved in the optimisation without constraints. Introducing the three constraints in turn resulted in peak heights of 2.21, 2.14 and 1.99 m. With all three types of constraints included, the peak height was similar to that achieved in the recorded performance. It is concluded that such considerations have a substantial influence on optimum technique and must be included in studies using optimised simulations.

As technology enters the nanometer territory, the antenna effect plays an important role in determining the yield and reliability of a VLSI circuit. Diode insertion and jumper insertion are the most effective techniques to fix the antenna effect. However, due to the increasing design complexity and the limited routing resource, applying diode or jumper insertion alone cannot achieve a high antenna fixing rate. In this paper, we give a polynomial-time antenna violation detection/fixing fixing algorithm by simultaneous diode/jumper insertion with minimum cost, based on a minimum-cost network-flow formulation. Experimental results show that our algorithm consistently achieves much higher antenna fixing rates than the state-of-the-art jumper insertion and diode insertion algorithms alone.

The Extravehicular Mobility Units (EMUs) onboard the International Space Station (ISS) experienced a failure due to cooling water contamination from biomass and corrosion byproducts forming solids around the EMU pump rotor. The coolant had no biocide and a low pH which induced biofilm growth and corrosion precipitates, respectively. NASA JSC was tasked with building hardware to clean the ionic, organic, and particulate load from the EMU coolant loop before and after Extravehicular Activity (EVAs). Based on a return sample of the EMU coolant loop, the chemical load was well understood, but there was not sufficient volume of the returned sample to analyze particulates. Through work with EMU specialists, chemists, (EVA) Mission Operations Directorate (MOD) representation, safety and mission assurance, astronaut crew, and team engineers, requirements were developed for the EMU Water Processing hardware (sometimes referred to as the Airlock Coolant Loop Recovery [A/L CLR] system). Those requirements ranged from the operable level of ionic, organic, and particulate load, interfaces to the EMU, maximum cycle time, operating pressure drop, flow rate, and temperature, leakage rates, and biocide levels for storage. Design work began in February 2005 and certification was completed in April 2005 to support a return to flight launch date of May 12, 2005. This paper will discuss the details of the design and certification of the EMU Water Processing hardware and its components

Summary Fractures of the talus are frequently difficult to treat. The vulnerable blood supply and abundant articular surfaces may lead to long-term problems with avascular necrosis and osteoarthritis. A case of a complex injury to the talus occurring in a rugby union player during a line-out is presented. The laws relating to line-out play disallow “lifting” and “levering” in the line out, but in reality allow “supporting” of the jumper on his shorts, once he has jumped. A further law insists on “lowering” of the supported jumper to the ground as soon as the ball has been won. This unusual injury to the talus clearly demonstrates the potential dangers of the line-out and the necessity that the laws of the game must be strictly adhered to, in order to ensure the safety of the line-out jumper.

We study in this paper the problem of jumper insertion on general routing (Steiner/spanning) trees with obstacles for antenna avoidance/fixing at the routing and/or post-layout stages. We formulate the jumper insertion for antenna avoidance/fixing as a tree-cutting problem and present the firstoptimal algorithm for the general tree-cutting problem. We show that the tree-cutting problem exhibits the properties of optimal substructures and greedy choices. With these properties, we present an O((V+D) lg D)-time optimal jumper insertion algorithm that uses the least number of jumpers to avoid/fix the antenna violations on a Steiner/spanning tree with V vertices and D obstacles. Experimental results show the superior effectiveness and efficiency of our algorithm.

Prototype optical interconnect modules with integrated polymer waveguides, out-of-plane reflector mirrors, and pluggable optical jumper connectors are fabricated. The modules have 5 dB insertion losses and can support 10+ Gb/s transmission at 850 nm.

Water ski jumping is one of the oldest disciplines in water skiing. The first jump was performed by Ralph Samuelson of Minnesota (US) in 1925, three years after he had invented water skiing. Samuelson jumped 18 m off the end of a greased ramp. Today water ski jumping is an international sport with elite male athletes jumping distances in excess of 70 m. The Sports Engineering Research Group (SERG) at the University of Sheffield have conducted a Computational Fluid Dynamic (CFD) analysis of the aerodynamic system of a water ski jumper for British Water Ski (BWS) in support of their 2005 World Championship campaign in China. The geometries of the water ski jumper and associated equipment were created using SERG’s in-house non-contact laser scanning facilities. Seven characteristic positional stages were analysed over the ski jump to obtain information on the fluctuations in lift and drag force acting upon the water ski jumper. The individual contribution of lift and drag, to the overall aerodynamic system of the water ski jumper, from each modeled component could be determined by the use of CFD. This indicated that the skis generate an average of 65 % of the entire system lift and drag, with the front third of the ski’s creating up to 50 % of these forces.

In view of the rate of 10 kV insulated conductor's lightning-caused break is higher than that of bare conductor, and some broken conductor's breakdown fractures are regular that can be jointed very well, and some have the case of plastic deformation, and etc., in this article, based on the conductor's melting point and electric-arc characteristic, from the specific property of materials mechanics and electromagnetism, the lightning-caused break mechanism of insulated aluminum conductor is analyzed qualitatively, and the following views are advanced: the steady burning location of short circuit current arc root is mainly related to the amount of lightning current, the joint effect by the vector of short current arc electromagnetic force, vector of electromagnetic force produced by the power frequency current and other forces, and the relative locations of high voltage and low voltage electrodes; the insulated aluminum conductor's low melting point, the arc root's fixed burning, the joint effect by reacting force produced by the axial alternating electromagnetic force of arc formed between high-voltage and low-voltage electrodes, and the tension produced by the dead weight of conductor, are the main reasons for break of the insulated conductor. The fractures of lightning-caused break are between brittle break and tough break. Preventive measure is also put forward in this article: arc-leading jumper can be installed at the straight pole where lightning stroke is easily occur, to lead the arc root to the tension clamp, so as to avoid lightning-caused break. (6 pages)

Antenna effect may damage gate oxides during plasma-based fabrication process. The antenna ratio of total exposed antenna area to total gate oxide area is directly related to the amount of damage. Jumper insertion is a common technique applied at routing and post-layout stages to avoid and to fix the problems caused by the antenna effect. This paper presents an optimal algorithm for jumper insertion under the ratio upper-bound. It handles Steiner trees with obstacles. The algorithm us based on dynamic programming while works on free trees. The time complexity is O(/spl alpha/|V|/sup 2/ ) and the space complexity is O(|V|/sup 2/), where |V| is the number of nodes in the routing tree and a is a factor depending on how to find a non-blocked position on a wire for a jumper.

The standing long jump is a standard test for primary school students. It can be used to evaluate the development of basic sports skills of a child. This paper presents a system that can automatically detect the motion during a standing long jump from a video sequence. The silhouette of the jumper in the film is segmented from the background first for all frames. A stick model is applied to the silhouette found in the first frame. Then a GA-based search algorithm is used to find the stick models for the rest of the frames. The stick model points out the important joints of a person and can be used to represent the pose of the jumper in each frame. From the pose change in consecutive frames, we will be able to analyze the movement of the jumper.

The authors propose motion analysis of ski jumping by data logging method using inertia sensors. A tri-axial accelerometer and a single axial gyroscope were attached onto the jumper’s body. Simultaneously, high speed cameras were equipped for the image capturing in order to obtain the jumper’s motion from the take-off and the middle phase of the flight. The characteristics of the ski jumper during whole phases were identified by using the inertia sensors.

Jumper's knee usually affects the patellar tendon and its proximal insertion. It is an overuse syndrome that can lead to anatomical modifications on bone and tendon tissues. Clinical examination show two elective pain sites: the tip of the patella and the central third of the patellar tendon. These signs can be emphasized with ultrasonographic imaging which can demonstrate bone and intratendinous lesions and their extent. If conservative treatments fail, surgery can be discussed. Excision of irreversible lesions provides good results.

In this study, we found that the optimum take-off angle for a long jumper may be predicted by combining the equation for the range of a projectile in free flight with the measured relations between take-off speed, take-off height and take-off angle for the athlete. The prediction method was evaluated using video measurements of three experienced male long jumpers who performed maximum-effort jumps over a wide range of take-off angles. To produce low take-off angles the athletes used a long and fast run-up, whereas higher take-off angles were produced using a progressively shorter and slower run-up. For all three athletes, the take-off speed decreased and the take-off height increased as the athlete jumped with a higher take-off angle. The calculated optimum take-off angles were in good agreement with the athletes' competition take-off angles.

We present and summarize the preliminary test results for SVX4 chip testing. There are presently two versions of the SVX4. Version 2 has on-chip bypassing and Version 1 does not. The on-chip bypassing is a layer of transistors under the front-end analog pipeline that acts as a bypassing capacitor for the voltage supply. Its size is about a microfarad. We aggressively choose to test Version 2 because of this feature. The feature is advantageous for hybrid design because it eliminates the need for an additional passive component on the hybrid itself by placing it on the actual SVX4 die. Also, the SVX4 was designed to operate in two modes: D. and CDF. One can set which mode the chip will operate by placing a jumper in the proper position on the SVX4 chip carrier. In either mode, the chip can either use the operating parameters from the shift register or the shadow register. Similarly, this is selected by placing a jumper on the SVX4 chip carrier. This chip has this feature because it was unknown whether the new design of the shadow register would be operable. The shadow register is also call the SEU register or Single Event Upset register. more » An introduction into the functionality of the chip and an explanation on the difference between D. and CDF mode can be found in the SVX4 User's Manual [1]. « less

The authors present a conceptual approach to improve the yield, efficiency, and pulse shape characteristics from an explosively-driven magneto-cumulative generator (MCG). We propose that a Bitter coil with tailored and configurable electromagnet windings and insulation be used for the MCG stator. Several features of Bitter coil construction lend themselves as design solutions for a number of inherent MCG problems. Standard Bitter coils have been used for decades to conduct high currents and produce correspondingly high magnetic fields. The Bitter coil is a series of conducting annular disks of considerable conducting cross-section. An azimuthal sector of conductor is removed from each annulus, which permits a break point for an axial "jumper" to connect each turn to its neighbor. The disks are stacked with interleaved insulation. For MCG application, the windings of the Bitter coil can in principle be modified, turn-by-turn, to change each winding's inner and outer radius and thickness, as well as the material, size, shape, and spacing of the interleaving insulation. This design variability seems to solve a number of performance problems of conventional MCGs. The authors have searched the open available technical literature and have not found any MCG research using this approach. Fabricating a Bitter coil-type stator may have been previously impractical, but with the advent of computer-numerical-controlled shop machines the lack of ease to fabricate such a stator may no longer be a hurdle for its use.

In the analysis of requirements for personnel canopies there are many pitfalls that must be overcome so that a clear picture of the canopy performance can be painted. This includes understanding of user requirements, instrumentation choices, development of appropriate test scenarios, and the processing of data into a clear and presentable forma t. This paper will discuss lessons learned in these areas for the Advanced Tactical Parachute System (ATPS) and Special Operation Forces Tactical Advanced Parachute System (SOFTAPS). ATPS is a complete system replacement for the US Army T -10D main canopy, reserve canopy, and harness. The SOFTAPS program is a replacement for the US Army MC1 -1D which will utilize the harness and reserve canopy from the ATPS program. The ATPS program has a performance requirement to “p rovide the jumper the ability to maneuver to avoid other jumpers and travel horizontally.” This does not define clearly what the user wants for a capability of the system. The approach taken during testing was to document what the ATPS system did with regards to canopy control performance, and com pare it to the currently fielded T-10D system. The challenge was to decide what critical data was necessary for analysis and then how to process the data into an understandable format. To understand the effect of canopy control, a 4 -DOF solution of positio n and jumper heading was needed, in addition to the time and type of jumper control inputs. The instrumentation decisions to achieve this are discussed in the paper. Also, the reduction of the data into a usable format such as strip charts and rendered vid eo is described along with the positives and negative s of each approach. The analysis of data into a useful format is critical to the success of a test program. Without understanding the correlation of cause and effect, the performance and characteristics of a personnel canopy cannot be defined. The SOFTAPS program has a requirement to have a “landing descent rate less than the MC1 -1C.” In order to evaluate the system performance of the SOFTAPS the orientation of the jumper, with respect to the wind directi on, must be collected as well as the vertical descent rate. This presents a challenge because the heading of the jumper’s body frame must be captured along with the wind direction throughout the drop. An area not typically addressed in the requirements fo r a system is the application of a measure to the data. For characterizing opening performance, YPG utilizes a running average of a set of test points. This average generates a smooth trace of the altitude loss versus vertical velocity, which is useful in understanding at what altitude loss events occurred and is key to the opening performance of the canopy and the determination of overall safety of the system. The requirements and system performance of the ATPS and SOFTAPS are discussed in detail in this paper. The paper also presents lessons learned for the ATPS and SOFTAPS programs, which includes a detailed discussion regarding altitude loss verses descent rate, opening shock, canopy control, and other personnel canopy performance measures.

Purpose The purpose was to examine the interacting roles played by the approach velocity, the explosive strength (represented by vertical ground reaction force [VGRF]), and the change in angular momentum about a transverse axis through the jumper's center of mass (deltaHzz) during the last support phase of the long jump, using a computer simulation technique. Methods A two-dimensional inverted-pendulum-plus-foot segment model was developed to simulate the last support phase. Using a reference jump derived from a jump performance reported in the literature, the effects of varying individual parameters were studied using sensitivity analyses. In each sensitivity analysis, the kinematic characteristics of the longest jumps with the deltaHzz considered and not considered when the parameter of interest was altered were noted. A sensitivity analysis examining the influence of altering both approach velocity and VGRF at the same time was also conducted. Results and conclusion The major findings were that 1) the jump distance was more sensitive to changes in approach velocity (e.g., a 10% increase yielded a 10.0% increase in jump distance) than to changes in the VGRF (e.g., a 10% increase yielded a 7.2% increase in jump distance); 2) the relatively large change in jump distance when both the approach velocity and VGRF were altered (e.g., a 10% increase in both parameters yielded a 20.4% increase in jump distance), suggesting that these two parameters are not independent factors in determining the jump distance; and 3) the jump distance was overestimated if the deltaHzz was not considered in the analysis.

The prototype optical interconnect modules with planar polymer waveguides, 45o reflector mirrors, and pluggable optical jumper connectors are demonstrated. The modules have 5 dB insertion losses and support 10+ Gbps data transmission.

As the process technology enters the nanometer era, reliability has become a major concern in the design and manufacturing of VLSI circuits. In this paper we focus on one reliability issue - jumper insertion in routing trees for avoiding/fixing antenna effect violations at the routing/post-layout stages. We formulate the jumper insertion for antenna avoidance/fixing as a tree-cutting problem. We show that the tree-cutting problem exhibits the properties of optimal substructures and greedy choices. With these properties, we present an O(V lg V)-time exact jumper insertion algorithm that uses the optimum number of jumpers to avoid/fix the antenna violations in a routing tree with V vertices. Experimental results show the superior effectiveness and efficiency of our algorithm.

DORIS Engineering and Stolt Offshore have jointly designed the three Girassol hybrid riser towers installed offshore Angola. They were the first riser towers designed to provide very efficient insulation properties in very deepwater conditions. Some towers are under development or construction for other fields but in similar design conditions. Based on the experience of Girassol, DORIS engineering and Stolt Offshore have developed the concept to adapt to much deeper waters (around 2500 m) and more severe environments such as the Gulf of Mexico loop current or hurricane waves. This paper will present the key drivers for design of riser towers in these environments addressing for example the impact on the bundle cross section, buoyancy requirements, top tank size, flexible jumper lengths. Limitations will be defined and explained both in terms of design, fabrication and installation. As FPSO units are likely to be part of the development of the Gulf of Mexico deepwater areas in the not-so-distant future, the benefit of riser towers will become obvious, given the existing facilities for fabrication along the coast and spreads for installation. Other areas such as the Mediterranean sea, or even the Northern North Sea are potential candidates for this type of riser arrangement which provides multiple benefits over steel catenary risers and flexible pipes.Copyright © 2005 by ASME

This chapter presents several tests carried out on an optic fiber system to determine the efficiency of a system. One of the tests is visible light continuity test commonly used to test short connecting cables called patchcords, patch cables, or jumper cables. These are short lengths of easily replaceable cable, typically 5–20 meters in length, used to connect between enclosures and instruments. Light source and power meter is used to measure the actual power loss of the fiber system. Mode stripper or mode filter makes the light escape much faster than in a normal fiber so that all the unwanted modes in about 300 mm (12 in) of fiber are lost. The optical time domain reflectometer (OTDR) is connected to one end of any fiber optic system up to 250 km in length. It enables measuring the overall loss, or the loss of any part of a system, the overall length of the fiber, and the distance between any points of interest, within few seconds. Fault locator devices are used to locate faults quickly and easily rather than providing a detailed analysis of a system, and are therefore more likely to be met in a repair environment than at a new installation.

Consider a skier who goes down a takeoff ramp, attains a speed V, and jumps, attempting to land as far as possible down the hill below (Fig. 1). At the moment of takeoff the angle between the skier's velocity and the horizontal is α. What is the optimal angle α that makes the jump the longest possible for the fixed magnitude of the velocity V? Of course, in practice, this is a very sophisticated problem; the skier's range depends on a variety of complex factors in addition to V and α. However, if we ignore these and assume the jumper is in free fall between the takeoff ramp and the landing point below, the problem becomes an exercise in kinematics that is suitable for introductory-level students. The solution is presented here.

A 21-year-old male professional trampoline gymnast consulted his physician to evaluate his activity-related anterior knee pain, present since 4 weeks. The most likely diagnosis was patellar tendinopathy, often termed jumper's knee. However, his symptoms did not match this diagnosis since the pain was located in the proximal part of the left knee with weakness, instability when standing up and …

The purpose of this paper is to discuss parachuting variables as they affect support and planning. The authors retrospectively analyzed an operation in which a Ranger battalion parachuted onto an airfield drop zone. Leaders weighed Rangers to estimate the soldiers' load. The advance team failed to adequately coordinate administrative medical assistance on the drop zone. Forty-one Rangers were injured and evacuated from the drop zone (8.6% of the jumpers). Variables in such operations include drop zone selection, equipment weight, drop altitude, wind speed, the wind-flight angle, drop height, and jumper density over the drop zone. Solutions include cargo drops and leaders' repeated emphasis on minimizing the soldiers' loads in accordance with mission accomplishment.

Optimal control simulations of the standing long jump were developed to gain insight into the mechanisms of enhanced performance due to arm motion. The activations that maximize standing long jump distance of a joint torque actuated model were determined for jumps with free and restricted arm movement. The simulated jump distance was 40 cm greater when arm movement was free (2.00 m) than when it was restricted (1.60 m). The majority of the performance improvement in the free arm jump was due to the 15% increase (3.30 vs. 2.86 m/s) in the take-off velocity of the center of gravity. Some of the performance improvement in the free arm jump was attributable to the ability of the jumper to swing the arms backwards during the flight phase to alleviate excessive forward rotation and position the body segments properly for landing. In restricted arm jumps, the excessive forward rotation was avoided by "holding back" during the propulsive phase and reducing the activation levels of the ankle, knee, and hip joint torque actuators. In addition, swinging the arm segments allowed the lower body joint torque actuators to perform 26 J more work in the free arm jump. However, the most significant contribution to developing greater take-off velocity came from the additional 80 J work done by the shoulder actuator in the jump with free arm movement.

A multi-segment model is used to investigate optimal compliant-surface jumping strategies and is applied to springboard standing jumps. The human model has four segments representing the feet, shanks, thighs, and trunk-head-arms. A rigid bar with a rotational spring on one end and a point mass on the other end (the tip) models the springboard. Board tip mass, length, and stiffness are functions of the fulcrum setting. Body segments and board tip are connected by frictionless hinge joints and are driven by joint torque actuators at the ankle, knee, and hip. One constant (maximum isometric torque) and three variable functions (of instantaneous joint angle, angular velocity, and activation level) determine each joint torque. Movement from a nearly straight motionless initial posture to jump takeoff is simulated. The objective is to find joint torque activation patterns during board contact so that jump height can be maximized. Minimum and maximum joint angles, rates of change of normalized activation levels, and contact duration are constrained. Optimal springboard jumping simulations can reasonably predict jumper vertical velocity and jump height. Qualitatively similar joint torque activation patterns are found over different fulcrum settings. Different from rigid-surface jumping where maximal activation is maintained until takeoff, joint activation decreases near takeoff in compliant-surface jumping. The fulcrum-height relations in experimental data were predicted by the models. However, lack of practice at non-preferred fulcrum settings might have caused less jump height than the models' prediction. Larger fulcrum numbers are beneficial for taller/heavier jumpers because they need more time to extend joints.

The aim of this study was to identify and explain the optimum projection angle that maximises the distance achieved in a standing long jump. Five physically active males performed maximum-effort jumps over a wide range of take-off angles, and the jumps were recorded and analysed using a 2-D video analysis procedure. The total jump distance achieved was considered as the sum of three component distances (take-off, flight, and landing), and the dependence of each component distance on the take-off angle was systematically investigated. The flight distance was strongly affected by a decrease in the jumper's take-off speed with increasing take-off angle, and the take-off distance and landing distance steadily decreased with increasing take-off angle due to changes in the jumper's body configuration. The optimum take-off angle for the jumper was the angle at which the three component distances combined to produce the greatest jump distance. Although the calculated optimum take-off angles (19-27 degrees) were lower than the jumpers' preferred take-off angles (31-39 degrees), the loss in jump distance through using a sub-optimum take-off angle was relatively small.

Petrobras presently has a significant part of its reserves located in deep and ultra deep waters. To produce this oil economically Petrobras created the well-known research program PROCAP 3000. This paper presents one project being developed under such program, the Extended Test for Deep and Ultra Deepwater. Petrobras has been using early production system and extended test for some years. Since 1998 Petrobras has been testing wells (extended test) with the Seillean FPSO (Floating Production Storage and Offloading). One challenge in this concept is the use of a dynamically positioned (DP) tanker with a rig and a threaded pipe (drill pipe riser) to produce and test wells in deep and ultra deep water. Another challenge is the frequency of changes of location of the FPSO, since the objective of an extended test is to produce for periods of three to twelve months. Therefore the system must have enough flexibility to make the installation and recovery easier. The proposed Itinerant Production and Evaluation Pilot System concept is easy to deploy and demobilize for extended trials. Under certain circumstances, it may even work as an Early Production System. It consists of a free-standing drill pipe riser system connected directly to the Christmas tree at the sea bed and to an air can at the top, which is located around 100 metes below sea surface. A flexible jumper links the air can to an FPSO. To improve production flow rate, an electric submersible pump (ESP) is installed at either downhole or at the top of Christmas tree. The main purpose of the extended test is to collect data, enhancing knowledge of the reservoir through more reliable information. Although attempting to minimize implementation costs, it may present a negative Net Present Value for shorter periods, especially if the value of the information obtained is not included in the calculation. Most of these ideas and concepts are still under study, and some of them will certainly be reassessed, reviewed and possibly improved. Petrobras has been working with some partner companies to develop the conceptual study and assess the system feasibility. This paper presents the main issues involved in this project. The objective of this paper is to summarize a preliminary conceptual design to conduct a feasibility analysis for Petrobras’ Free Standing Drill Pipe Riser (FSDPR).Copyright © 2004 by ASME

This work describes the generation of numerical models for the coupled analysis of a semisubmersible platform to be installed in Campos Basin, and presents the results, in terms of platform motions, of a set of analyses under fatigue environmental loading cases. The coupled model comprises the hull, the mooring lines, and all risers connected to the platform. The model includes also a FSHR (Free Standing Hybrid Riser) system to be connected to the platform; this system is composed by a rigid riser, an air can and a flexible jumper. A set of environmental loading cases appropriate for fatigue analyses is defined, in terms of current profile, irregular bi-directional seastate, and wind. For each loading case, nonlinear time-domain dynamic analyses are performed employing the Prosim program. This program is based in a coupled formulation that incorporates, in a single code and data structure, a hydrodynamic model to represent the hull, and a finite element model to rigorously represent the structural/hydrodynamic behavior of the lines. At every time step of the time integration of the equations of motion representing the hull, a series of nonlinear dynamic analysis of the lines is performed following a subcycling procedure. The results of the coupled analysis are expressed as time histories of platform motions. The next step is to proceed to the treatment of these time series, in order to determine, for each loading case: a) The frequency spectra of each motion component; and b) Representative statistical values in terms of static offsets, first and second-order motions (standard deviations and periods for low-frequency and wave-frequency motions). The platform motions that result from the coupled analyses presented in this work can be employed to perform the detailed structural analysis of the FSHR system, by employing an isolated model of the riser in a specialized program.

The pattern of several blood–gas indices has been investigated in eight show jumpers during a 2-day showjumping event. The effectiveness of the athlete horse’s physiological buffering systems has been pointed out, as well as the similarity between the patterns of the indices regarding the acid–base status and those metabolically defining the horse’s physical potential. The results of this study draw attention to the importance of a qualitative and quantitative determination of the blood–gas parameters in the show jumper, not only to define the horse’s acid–base status but also to analyse the potential performance more accurately.

A flip-chip waveguide coupler with an order of magnitude greater alignment tolerance than competing approaches is presented for the first time. Experimental data for an "optical jumper" agree with simple design considerations. Application to a planar lightwave circuit-based surface mount photonics platform is outlined.

Acute traumatic proximal tibiofibular joint dislocation is an exceedingly rare injury. This is a case report in a rare horizontal type joint variant, following a long jump injury. The diagnostic approach when this injury is suspected is described.

Abstract This paper describes the design and installation of the twin 12- inch flowlines for the Canyon Express project. In addition to the world record-breaking water depth of 7,280 ft (2,220 m) in Mississippi Canyon block 348, several challenges were met and overcome by the design and installation team. Some of these challenges were: the fast track nature of the project; ten in-line sleds and two end-of-line sleds to be installed within tight tolerance areas on the seafloor; in the King's Peak field three sleds to be in the flowline catenary simultaneously with two of these 3,200 feet apart landing in a curve in 6,400-foot water depth; in the Aconcagua field two sleds to be in the catenary 3,700 feet apart in 7,100-foot water depth. The Canyon Express project management team was lead by TotalFinaElf and included engineers in lead positions from the operating partners (BP and Marathon Oil). INTEC Engineering provided support from conceptual to detailed design in all aspects of the project, except drilling. Saipem was the flowline sled detail designer, fabricator, and installation contractor. The vessel used for the deepwater portion of the work was the SaiBOS Field Development Ship (FDS). Shallow water flowline installation work was performed with EMC's Castoro 10. This paper describes several aspects of the Canyon Express project which includes a number of issues pertinent to deepwater flowline work: field development concept leading to selection of the daisy chain concept, flowline mechanical design, installation scope of work and bid strategy, the King's Peak multiple sled installation challenge, multi-phase flow meter and jumper design, installation procedures, and execution of the offshore work. Saipem completed installation of the Canyon Express flowlines in the summer of 2002. The success of this endeavor is due in large part to the collaborative and team philosophy adopted by TotalFinaElf, as well as careful planning and attention to detail of the subsea components and equipment involved. Introduction One of the unique features of the Canyon Express development is that it commingles in a single delivery system the production of three different fields: BP's King's Peak (currently with three producing wells), TotalFinaElf's Aconcagua (four producing wells), and Marathon's Camden Hills (two producing wells). Production from each field is dry gas with nominal amounts of condensate. Expected production rates are in the range of 100 to 250 MMSCFD per flowline. As can be seen in Figure 1, the fields are connected by two (an east and a west) 12-inch flowlines (each approximately 55 mile long) in a daisy chain layout forming a piggable loop. Joining of the two flowlines at the deep end is made with the aid of a 12-inch jumper. The flowlines connect the MP261 JP Canyon Station platform (located in Main Pass 261 in 299 feet water depth) to the King's Peak field 39 miles away at a 6,400 ft water depth, then to the Aconcagua field 11 miles away at 7,100 feet water depth, and finally to the Camden Hills field 5 miles away at 7,280 feet water depth. The flowlines are routed such that they are laid at 60 feet nominal distance to each well.

Installing a new or replacement generator requires careful consideration during installation, offline acceptance testing and increased diligence during initial start-up and operation. After replacing the first of four 132 MVA, 15 kV, 85.7 RPM Allis-Chalmers hydrogenerator stators, Chelan County PUD personnel were confronted with an unexpected distribution of generator stator RTD temperatures during the initial unit start-up. A correlation was established between the location of the higher stator winding RTD readings and the region of overheating shown on a continuous infrared thermal imaging display provided by data from a permanently installed array of fast-response, infrared sensors mounted on the rotor. The thermal map pattern provided a classic indication of circulating currents in a phase circuit. This condition is often seen in windings that have cutout coils. The generating unit operated in this condition for fewer than three weeks before a coil-to-coil jumper failed causing a severe arc that finally went to ground, tripping the unit on a ground fault.

A comparison of Small Form Factor (SFF) fiber optic connectors is presented for LC, MT-RJ, SC-DC, and VF-45. Multimode and singlemode jumper cables were tested using industry standard test procedures and bench marked against the industry standard SC Duplex connector. Initial loss data as well as stress testing was performed. Variations were found in the performance of the connectors types and between connectors of the same type from different suppliers. In some cases the connectors out performed the SC Duplex on some tests but no connectors out performed the SC Duplex on all tests with the mechanical stress tests of axial and off-axial pull being the most difficult to exceed. These connectors are rapidly developing and are at different levels of maturity but none of them tested out to be a fully mature replacement for the SC Duplex connector yet.