WorldWideScience

Sample records for ball and socket joints

  1. De Quervain Tenosynovitis Following Trapeziometacarpal Ball-and-Socket Joint Replacement.

    Science.gov (United States)

    Goubau, Jean F; Goubau, Laurent; Goorens, Chul Ki; van Hoonacker, Petrus; Kerckhove, Diederick; Vanmierlo, Bert; Berghs, Bart

    2015-02-01

    Background One of the surgical treatment options for trapeziometacarpal (TMC) joint arthritis is a prosthetic ball-and-socket replacement. One of the complications in the postoperative setting is de Quervain tendinopathy. Purposes Although this complication has been reported following a resection athroplasty, we questioned whether lengthening of the thumb following the Ivory (Memometal, Stryker Corporate, Kalamazoo, MI, USA) ball-and-socket arthroplasty could be a causal factor. Methods In a prospective study regarding the overall outcome of the Ivory prosthesis, we analyzed 96 cases (83 patients; 69 female, 12 male, 8 bilateral) of primary implanted Ivory prosthesis and the incidence of de Quervain disease during the first year following surgery. We found a particularly high incidence (17%) of de Quervain tendinopathy the first year following this ball-and-socket arthroplasty. We measured the lengthening of the thumb radiographically in the group presenting de Quervain and the asymptomatic group and compared this measure between the two groups. Results We did not find any measurable or statistically significant difference between the groups regarding lengthening. Discussion These findings suggest that lengthening of the thumb following ball-and-socket arthroplasty is not a causal factor in the development of de Quervain tendinopathy within one year after surgery.

  2. The Effect of Mechanical Combined Contact Stress with Buckling Load on the Stress Distribution in the Ball and SocketJoint Mechanism

    OpenAIRE

    Fatima Salman; Fathi AL Shamaa

    2010-01-01

    The design of components subjected to contact stress as local compressive stress is important in engineering application especially in ball and socket Joining. Two kinds of contact stress are introduced in the ball and socket joint, the first is from normal contact while the other is from sliding contact. Although joining two long links (drive shaft in steering cars) will cause the effect of flexural and tensional buckling stress in hollow columns through the ball and socket ends on the failu...

  3. Biomechanical Aspects of Shoulder and Hip Articulations: A Comparison of Two Ball and Socket Joints

    Directory of Open Access Journals (Sweden)

    Mustafa Qusay Ismael

    2006-01-01

    Full Text Available The shoulder and hip joints though essentially both are ball and socket joints, show structural variability to serve functional needs.study aims at revealing some of the structural and functional properties of each of the two joints regarding the factors that contribute to the stability of any joint in the body, namely: bone, ligament, and muscleTwenty dried scapula, hip, humerus, and femur were used. The area of the articular surfaces was estimated by molding a sheet of dental wax. Using special graphics software, a novel procedure was described to calculate the area under the curve, which was postulated to indicate the degree of curvature. Tension test was applied using a testometric machine, which was locally modified to suit biological specimens. A finite element analysis was designed to study the articulating bones under different loading conditionsIn the hip joint, the area of the articular surface of the head of the femur and that of the lunate showed no significant statistical difference. For the shoulder joint, the articular areas of the head of the humerus and the glenoid were statistically different. No statistical significance was observed regarding curvature of the articular surfaces within both the hip and shoulder joints; however, the values were significantly different between the hip and shoulder. In the tension test, the site of rupture of the capsule of the shoulder joint was found to be at its anteroinferior part. The more contact between the area of the cup and ball, as was demonstrated in the hip joint, the more stable the joint. On the contrary, the shoulder articular surfaces have less area of contact, which makes it more mobile and decreases stability. The insignificant difference in curvature within both joints indicates a good congruity and thus more stability especially during joint movement. The curvature difference between the head of femur and the head of humerus indicates that the range of motion is quite

  4. Ankle and subtalar synovitis in a ball-and-socket ankle joint causing posterolateral painful coarse crepitus: a case report.

    Science.gov (United States)

    Fan, Ka Yuk; Lui, Tun Hing

    2014-01-01

    A 17-year-old girl with bilateral ball-and-socket ankles reported left medial heel pain. Her left heel had gone into a varus position on tiptoeing, and a painful clunk had occurred when returning to normal standing. The clunk persisted after physiotherapy and treatment with an orthosis. Subtalar arthroscopy and peroneal tendoscopy showed mild diffuse synovitis of the ankle joint, especially over the posterior capsule, and a patch of inflamed and fibrotic synovium at the posterolateral corner of the subtalar joint. The clunk subsided immediately after arthroscopic synovectomy and had not recurred during 5 years of follow-up. We found no other reported cases of ankle and subtalar synovitis occurring in patients with a ball-and-socket ankle joint. PMID:25179452

  5. The Effect of Mechanical Combined Contact Stress with Buckling Load on the Stress Distribution in the Ball and SocketJoint Mechanism

    Directory of Open Access Journals (Sweden)

    Fatima Salman

    2010-01-01

    Full Text Available The design of components subjected to contact stress as local compressive stress is important in engineering application especially in ball and socket Joining. Two kinds of contact stress are introduced in the ball and socket joint, the first is from normal contact while the other is from sliding contact. Although joining two long links (drive shaft in steering cars will cause the effect of flexural and tensional buckling stress in hollow columns through the ball and socket ends on the failure condition of the joining mechanism. In this paper the consideration of the combined effect of buckling Load and contact stress on the ball and socket joints have been taken, epically on the stress distribution in the contact area. Different parameters have been taken in the design of joint. This is done by changing the angles for applied loads with the principle axis, the angle of contact between ball and socket and using different applied loads. The problem has been solved using analytical solution for computing the critical loads and using these loads for calculating the stress distribution with finite element method using ANSYS 10. The numerical results have been compared with the experimental method using photo elasticity pattern which shows good agreement between experimental and simulation results.

  6. Ball and socket ankle joint in connection with bilateral tarsal synostosis in a boy with congenital absence of the portal vain: a novel malformation complex

    OpenAIRE

    Zandieh, Shahin; Vakli-Adli, Anosheh; Hochreiter, Josef; Grill, Franz; Klaushofer, Klaus; Al Kaissi, Ali

    2008-01-01

    Background Contracted valgus flat foot in the adolescent is frequently caused by tarsal synostosis or synchondrosis. These synostoses are prevalently symptomatic during adolescence, when by ossifying they block the subtalar joint in valgus. Careful and detailed examinations might reveal additional abnormalities. Case presentation A 16-year-old boy of Austrian origin presented with contracted valgus foot associated with tarsal hypomobility and pain. Talonavicular synostosis with ball and socke...

  7. A new principle and device for large aircraft components gaining accurate support by ball joint

    Institute of Scientific and Technical Information of China (English)

    Bao-gui QIU; Jun-xia JIANG; Ying-lin KE

    2011-01-01

    How to obtain an accurate support for large components by ball joint is a key process in aircraft digital assembly. A novel principle and device is developed to solve the problem. Firstly, the working principle of the device is introduced. When three or four displacement sensors installed in the localizer are touched by the ball-head, the spatial relation is calculated between the large aircraft component's ball-head and the localizer's ball-socket. The localizer is driven to achieve a new position by compensation. Relatively, a support revising algorithm is proposed. The localizer's ball-socket approaches the ball-head based on the displacement sensors. According to the points selected from its spherical surface, the coordinates of ball-head spherical center are computed by geometry. Finally, as a typical application, the device is used to conduct a test-fuselage's ball-head into a localizer's ball-socket. Positional deviations of the spherical centers between the ball-head and the ball-socket in the x, y, and z directions are all controlled within ±0.05 mm under various working conditions. The results of the experiments show that the device has the characteristics of high precision, excellent stability, strong operability, and great potential to be applied widely in the modern aircraft industry.

  8. Ball-and-socket tectonic rotation during the 2013 Mw7.7 Balochistan earthquake

    Science.gov (United States)

    Barnhart, W. D.; Hayes, G. P.; Briggs, R. W.; Gold, R. D.; Bilham, R.

    2014-10-01

    The September 2013 Mw7.7 Balochistan earthquake ruptured a ˜200-km-long segment of the curved Hoshab fault in southern Pakistan with 10±0.2 m of peak sinistral and ˜1.7±0.8 m of dip slip. This rupture is unusual because the fault dips 60±15° towards the focus of a small circle centered in northwest Pakistan, and, despite a 30° increase in obliquity along strike, the ratios of strike and dip slip remain relatively uniform. Surface displacements and geodetic and teleseismic source inversions quantify a bilateral rupture that propagated rapidly at shallow depths from a transtensional jog near the northern end of the rupture. Static friction prior to rupture was unusually weak (μ<0.05), and friction may have approached zero during dynamic rupture. Here we show that the inward-dipping Hoshab fault defines the northern rim of a structural unit in southeast Makran that rotates - akin to a 2-D ball-and-socket joint - counter-clockwise in response to India's penetration into the Eurasian plate. This rotation accounts for complexity in the Chaman fault system and, in principle, reduces seismic potential near Karachi; nonetheless, these findings highlight deficiencies in strong ground motion equations and tectonic models that invoke Anderson-Byerlee faulting predictions.

  9. Wear-testing of a temporomandibular joint prosthesis : UHMWPE and PTFE against a metal ball, in water and in serum

    NARCIS (Netherlands)

    Van Loon, JP; Verkerke, GJ; de Bont, LGM; Liem, RSB

    1999-01-01

    For a temporomandibular joint prosthesis, an estimation of the wear rate was needed, prior to patient application. Therefore, we determined the in vitro wear rate of the ball-socket articulation of this prosthesis, consisting of a metal head and an ultra-high molecular weight polyethylene (UHMWPE) c

  10. Patient satisfaction and preference with magnet, bar-clip, and ball-socket retained mandibular implant overdentures : A cross-over clinical trial

    NARCIS (Netherlands)

    Cune, Marco; van Kampen, Frits; van der Bilt, Andries; Bosman, Frits

    2005-01-01

    Purpose: The purposes of this study were to: (1) determine patient satisfaction with implant-supported mandibular overdentures using magnet, bar-clip, and ball-socket attachments; and (2) assess the relation between maximum bite force and patient satisfaction. Materials and Methods: In a cross-over

  11. Temporomandibular joint dislocation and deafness from a cricket ball injury.

    Science.gov (United States)

    Murthy, P; Bandasson, C; Dhillon, R S

    1994-05-01

    Cricket is a national sport in some countries and can be potentially hazardous. We report an incident of a cricket ball impact to the chin, which resulted in posterior dislocation of both temporomandibular joints and bilateral mixed deafness. There appear to be no similar case reports in the literature.

  12. 滚动球窝喷管动态性能分析%Dynamic Characteristics Analysis of Rolling Ball Joint Socket Nozzle

    Institute of Scientific and Technical Information of China (English)

    刘文芝; 武建新; 薛俊芳; 李超超; 赵永忠

    2013-01-01

    In order to test the correctness of the dynamic performance and structural design for rolling ball nozzle solid rocket motor in extreme load condition,the finite method was adopted in theoretical calculation. Inside the system joint,the rigid crash between the ball and the separator in the joint was simulated as a parallel nonlinear spring damper,and to flexibly describe its elasticity by the convex-concave model. At the same time,the elastic contact model between the rolling body and the convex-concave sphere model was established by introducing the calculation result of the elastic-plastic frictional contact deformation. In consideration of the weight,moment of inertia,material characteristics and friction of the mechanism,coupled rigid and flexible multi-body dynamics model of complete machine was established. Movement disciplinarian,dynamic contact force,excursion of sway center and instantaneous driving moment of mechanism components were obtained. The comparison is made between the measurement and the simulated results. The rationality and validity of the dynamics modeling methods and the calculation results were validated.%为检验极端载荷作用下,固体火箭发动机滚动球窝喷管动态性能及结构设计的正确性,理论计算中,接头内部,用并联非线性弹簧阻尼器,表征滚动体与保持架间的刚性碰撞;用有限元法为数学工具,以阴、阳球的模态柔性描述其弹性,同时引入弹塑性摩擦接触变形的数值计算结果,建立滚动体与阴、阳球间的弹性接触模型;充分考虑各构件的重量、转动惯量、材料特性及摩擦,建立系统整机刚柔耦合多体动力学模型.计算得到系统及接头内各主要零部件的运动规律、动态接触力、系统摆心漂移量及瞬时作动力矩.通过与系统冷试车试验所测力矩的对比论证,检验动力学建模方法及计算结果的合理性、正确性.

  13. 2D Ball-and-Socket Tectonic Rotation in a Heterogeneous Strain Field: The 2013 Mw7.7 Balochistan, Pakistan Earthquake

    Science.gov (United States)

    Barnhart, W. D.; Hayes, G. P.; Briggs, R. W.; Gold, R. D.; Bilham, R. G.

    2014-12-01

    The September 2013 Mw7.7 Balochistan strike-slip earthquake ruptured a ~200 km long segment of the curved Hoshab fault within the Makran accretionary prism - the active zone of convergence between the northward subducting Arabia plate and overriding Eurasia. The Hoshab fault ruptured bilaterally with ~10 m of mean sinistral and ~1.7 m of dip slip along the length of the rupture, quantified jointly from geodetic and seismological observations. This rupture is unusual because the fault dips ~60o towards the focus of a small circle centered in northwest Pakistan, and, despite a 30o increase in obliquity along the curving strike of the fault with respect to Arabia:Eurasia convergence, the ratio of strike and dip slip remain relatively uniform. Static friction prior to rupture was unusually weak ( <0.05) as inferred from topographic and slab profiles, and friction may have approached zero during dynamic rupture, thus permitting in part this unusual event. In this presentation, we argue that the northward dipping Hosab fault defines the northern rim of a structural unit in southeast Makran. This unit rotates - akin to a 2-D ball-and-socket joint - counter clockwise in response to India's penetration into the Eurasia plate. According to this interpretation, the mechanically weak Makran accretionary prism is subjected to a highly heterogeneous strain and deforms in response to convergence from both the Arabia and India plates. Rotation of the southeast Makran block accounts for complexity in the Chaman fault system and, in principle, reduces the seismic potential near Karachi by accommodating some slip along the southern Ornach-Nal fault. At the same time, geological indicators and along-strike fault slip profiles indicate that the Hoshab fault may also slip as a reverse fault in response to Arabia:Eurasia convergence - indicating that a single fault may accommodate multiple components of strain partitioning in a heterogeneous strain field over several seismic cycles.

  14. Study on torsional fretting wear behavior of a ball-on-socket contact configuration simulating an artificial cervical disk

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Song [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China); Wang, Fei [School of Material Science and Engineering, China University of Mining and Technology, Xuzhou 221116 (China); Liao, Zhenhua [Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China); Biomechanics and Biotechnology Lab, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057 (China); Wang, Qingliang [School of Material Science and Engineering, China University of Mining and Technology, Xuzhou 221116 (China); Liu, Yuhong [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China); Liu, Weiqiang, E-mail: weiqliu@hotmail.com [Biomechanics and Biotechnology Lab, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057 (China); State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China)

    2015-10-01

    A ball-on-socket contact configuration was designed to simulate an artificial cervical disk in structure. UHMWPE (ultra high molecular weight polyethylene) hot pressed by powders and Ti6Al4V alloy were selected as the material combination of ball and socket. The socket surface was coated by a ~ 500 nm C-DLC (carbon ion implantation-diamond like carbon) mixed layer to improve its surface nano hardness and wear resistance. The torsional fretting wear behavior of the ball-on-socket model was tested at different angular displacements under 25% bovine serum lubrication with an axial force of 100 N to obtain more realistic results with that in vivo. The fretting running regimes and wear damage characteristics as well as wear mechanisms for both ball and socket were studied based on 2D (two dimension) optical microscope, SEM (scanning electron microscope) and 3D (three dimension) profiles. With the increase of angular displacement amplitude from 1° to 7°, three types of T-θ (Torsional torque-angular displacement amplitude) curves (i.e., linear, elliptical and parallelogram loops) corresponding to running regimes of PSR (partial slip regime), MR (mixed regime) and SR (slip regime) were observed and analyzed. Both the central region and the edge zone of the ball and socket were damaged. The worn surfaces were characterized by wear scratches and wear debris. In addition, more severe wear damage and more wear debris appeared on the central region of the socket at higher angular displacement amplitude. The dominant damage mechanism was a mix of surface scratch, adhesive wear and abrasive wear for the UHMWPE ball while that for the coated socket was abrasive wear by PE particles and some polishing and rolling process on the raised overgrown DLC grains. The frictional kinetic behavior, wear type, damage region and damage mechanism for the ball-on-socket model revealed significant differences with those of a ball-on-flat contact while showing better consistency with that of in

  15. Study on torsional fretting wear behavior of a ball-on-socket contact configuration simulating an artificial cervical disk.

    Science.gov (United States)

    Wang, Song; Wang, Fei; Liao, Zhenhua; Wang, Qingliang; Liu, Yuhong; Liu, Weiqiang

    2015-10-01

    A ball-on-socket contact configuration was designed to simulate an artificial cervical disk in structure. UHMWPE (ultra high molecular weight polyethylene) hot pressed by powders and Ti6Al4V alloy were selected as the material combination of ball and socket. The socket surface was coated by a ~500 nm C-DLC (carbon ion implantation-diamond like carbon) mixed layer to improve its surface nano hardness and wear resistance. The torsional fretting wear behavior of the ball-on-socket model was tested at different angular displacements under 25% bovine serum lubrication with an axial force of 100 N to obtain more realistic results with that in vivo. The fretting running regimes and wear damage characteristics as well as wear mechanisms for both ball and socket were studied based on 2D (two dimension) optical microscope, SEM (scanning electron microscope) and 3D (three dimension) profiles. With the increase of angular displacement amplitude from 1° to 7°, three types of T-θ (Torsional torque-angular displacement amplitude) curves (i.e., linear, elliptical and parallelogram loops) corresponding to running regimes of PSR (partial slip regime), MR (mixed regime) and SR (slip regime) were observed and analyzed. Both the central region and the edge zone of the ball and socket were damaged. The worn surfaces were characterized by wear scratches and wear debris. In addition, more severe wear damage and more wear debris appeared on the central region of the socket at higher angular displacement amplitude. The dominant damage mechanism was a mix of surface scratch, adhesive wear and abrasive wear for the UHMWPE ball while that for the coated socket was abrasive wear by PE particles and some polishing and rolling process on the raised overgrown DLC grains. The frictional kinetic behavior, wear type, damage region and damage mechanism for the ball-on-socket model revealed significant differences with those of a ball-on-flat contact while showing better consistency with that of in

  16. Structural dynamic analysis of a ball joint

    Science.gov (United States)

    Hwang, Seok-Cheol; Lee, Kwon-Hee

    2012-11-01

    Ball joint is a rotating and swiveling element that is typically installed at the interface between two parts. In an automobile, the ball joint is the component that connects the control arms to the steering knuckle. The ball joint can also be installed in linkage systems for motion control applications. This paper describes the simulation strategy for a ball joint analysis, considering manufacturing process. Its manufacturing process can be divided into plugging and spinning. Then, the interested responses is selected as the stress distribution generated between its ball and bearing. In this paper, a commercial code of NX DAFUL using an implicit integration method is introduced to calculate the response. In addition, the gap analysis is performed to investigate the fitness, focusing on the response of the displacement of a ball stud. Also, the optimum design is suggested through case studies.

  17. Joint prosthesis and method of bone fixation

    NARCIS (Netherlands)

    Oosterom, R.; Van der Pijl, A.J; Bersee, H.E.N.; Van der Helm, F.C.; Herder, J.L

    2006-01-01

    The invention relates to a joint prosthesis (10), for example, a knee joint or shoulder joint prosthesis comprising a first, socket-holding prosthesis part (11) for attachment to a first bone (12) and a second, ball-holding prosthesis part (13) for attachment to a second bone (14) that intermates wi

  18. Strength evaluation of prosthetic check sockets, copolymer sockets, and definitive laminated sockets

    Directory of Open Access Journals (Sweden)

    Michael L. Haynes, MS

    2012-04-01

    Full Text Available A prosthesis encounters loading through forces and torques exerted by the person with amputation. International Organization for Standardization (ISO standard 10328 was designed to test most lower-limb prosthetic components. However, this standard does not include prosthetic sockets. We measured static failure loads of prosthetic sockets using a modified ISO 10328 and then compared them with the criteria set by this standard for other components. Check socket (CS strengths were influenced by thickness, material choice, and fabrication method. Copolymer socket (CP strengths depended on thickness and fabrication methods. A majority of the CSs and all of the CPs failed to pass the ISO 10328 ductile loading criterion. In contrast, the strengths of definitive laminated sockets (DLs were influenced more by construction material and technique. A majority of the DLs failed to pass the ISO 10328 brittle loading criterion. Analyzing prosthetic sockets from a variety of facilities demonstrated that socket perfor-mance varies considerably between and within facilities. The results from this article provide a foundation for understanding the quality of prosthetic sockets, some insight into possible routes for improving the current care delivered to patients, and a comparative basis for future technology.

  19. Tensile strength and impact resistance properties of materials used in prosthetic check sockets, copolymer sockets, and definitive laminated sockets

    Directory of Open Access Journals (Sweden)

    Maria J. Gerschutz, PhD

    2011-10-01

    Full Text Available Prosthetic sockets serve as the interface between people with amputations and their prostheses. Although most materials used to make prosthetic sockets have been used for many years, knowledge of these materials' properties is limited, especially after they are subjected to fabrication processes. This study evaluated tensile and impact properties of the current state-of-the-art materials used to fabricate prosthetic check sockets, copolymer sockets, and definitive laminated sockets. Thermolyn Rigid and Orfitrans Stiff check socket materials produced significantly lower tensile strength and impact resistance than polyethylene terephthalate glycol (PETG. Copolymer socket materials exhibited greater resistance to impact forces than the check socket materials but lower tensile strengths than PETG. The heated molding processes, for the check socket and copolymer materials, reduced both tensile strength and elongation at break. Definitive laminated sockets were sorted according to fabrication techniques. Nyglass material had significantly higher elongation, indicating a more ductile material than carbon-based laminations. Carbon sockets with pigmented resin had higher tensile strength and modulus at break than nonpigmented carbon sockets. Elongation at yield and elongation at break were similar for both types of carbon-based laminations. The material properties determined in this study provide a foundation for understanding and improving the quality of prosthetic sockets using current fabrication materials and a basis for evaluating future technologies.

  20. 21 CFR 888.3510 - Knee joint femorotibial metal/polymer constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3510...-and-socket joint located between a stemmed femoral and a stemmed tibial component and a runner and track joint between each pair of femoral and tibial condyles. The ball-and-socket joint is composed of...

  1. Development of fatigue resistance evaluation method for socket-weld-jointed pipes

    International Nuclear Information System (INIS)

    Vent line, drain line and sampling line in nuclear power station have many socket welded-joints made of austenitic stainless steel. Their slenderness and stagnation yield some potential of vibration-induced cracking and stress corrosion cracking. For the joints under vibration, the authors firstly elucidated their welding-defect-related fatigue strength by using fracture mechanics. It could define the allowable sets of stress amplitude and defect size. Secondly, authors developed an ultra-sonic detecting apparatus by using a focus-type probe and its programmed crawl on socket part. The authors finally measured the stress amplitude and frequency by sticking strain gage on suspected joints, then evaluated the fatigue resistance of the joints. For more efficient procedure, the method of stress amplitude analysis through vibration measurement is being developed. (author)

  2. Ultrasonic defect detection method for socket welding joint

    International Nuclear Information System (INIS)

    The present invention provides a method of detecting defects over a wide range of a socket weld portion of various kinds of pipelines used, for example, in a nuclear power plant. Namely, an inclined probe is disposed to a jig for detecting defects by ultrasonic waves. This is rotated at least by one turn along the peripheral surface of the material to be detected such as weld tube joints. Defects of weld portion of the material can be detected automatically by using ultrasonic waves during the rotation. The inclined probe for detecting defects by ultrasonic waves comprises a transmission portion having a planar transmittance oscillator disposed to a wedge on the transmission side and a receiving portion comprising a planar receiving oscillator disposed to a wedge on the receiving side. With such a constitution, ultrasonic waves are emitted from the transmission portion to the defect detection portion in the welded portion. If a defect is present, defective echo is reflected to the receiving portion disposed ahead of the probe. Since the defective echo changes depending on the height of the detective portion, the estimation of the height of the defect can be facilitated. (I.S.)

  3. Joint prosthesis and method of bone fixation

    OpenAIRE

    Oosterom, R; Pijl, A J; Bersee, H.E.N.; Van der Helm, F.C.; Herder, J. L.

    2006-01-01

    The invention relates to a joint prosthesis (10), for example, a knee joint or shoulder joint prosthesis comprising a first, socket-holding prosthesis part (11) for attachment to a first bone (12) and a second, ball-holding prosthesis part (13) for attachment to a second bone (14) that intermates with the first prosthesis part, wherein the first bone and the second bone are situated at either side of a joint, and wherein the ball (2) of the second prosthesis part is rotatably received in the ...

  4. Process Design of a Ball Joint, Considering Caulking and Pull-Out Strength

    Directory of Open Access Journals (Sweden)

    Bong-Su Sin

    2014-01-01

    Full Text Available A ball joint for an automobile steering system is a pivot component which is connected to knuckle and lower control arm. The manufacturing process for its caulking comprises spinning and deforming. In this study, the process was simulated by flexible multibody dynamics. The caulking was evaluated qualitatively through numerical analysis and inspecting a plastically deformed shape. The structural responses of a ball joint, namely, pull-out strength and stiffness, are commonly investigated in the development process. Thus, following the caulking analysis, the structural responses were considered. In addition, three design variables related to the manufacturing process were defined, and the effects of design variables with respect to pull-out strength, caulking depth, and maximum stress were obtained by introducing the DOE using an L9 orthogonal array. Finally, the optimum design maximizing the pull-out strength was suggested. For the final design, the caulking quality and the pull-out strength were investigated by making six samples and their tests.

  5. Titanium ball joint total ossicular replacement prosthesis--experimental evaluation and midterm clinical results.

    Science.gov (United States)

    Gostian, A O; Pazen, D; Luers, J C; Huttenbrink, K B; Beutner, D

    2013-07-01

    During reconstruction of the ossicular chain, there is a need to address the forces and loads caused by the ambient atmospheric pressure variations and the resulting tympanic membrane movements. It is understood that when a rigid middle ear prosthesis is inserted the malleoincudal joint, a keyfactor in controlling pressure variations in the middle ear space is bypassed. In this paper we describe a modified total titanium ossicular replacement prosthesis with an innovative micro ball joint in the headplate which is designed to compensate for tympanic membrane movements caused by atmospheric pressure variations. The characteristics of this modified prosthesis were examined in temporal bone experiments and compared to the standard titanium total ossicular reconstruction prosthesis. Sound-induced stapes footplate movements were investigated by means of a Laser vibrometer and revealed no significant differences between the two prostheses in vitro. Intraoperatively, the insertion of the modified prosthesis required more delicate handling. The angle between the shaft and the headplate was variable and ranged from 60 to 90° as estimated by the surgeon. Twelve consecutive patients were eligible for clinical evaluation. The pure tone average (PTA) air-bone gap after a mean follow up period of 32 months was 18.8 dB. Furthermore, no extrusion, dislocation or other adverse events were observed. We conclude that the modified total ossicular replacement prosthesis with integrated micro ball joint yields similar volume velocities of the stapes footplate in the laboratory experiments compared to the standard rigid prosthesis. The audiological and morphological results are encouraging and show that the mobile prosthesis headplate adjusting to the level of the tympanic membrane is a further step in the development of a physiological middle ear implant. This article is part of a special issue entitled "MEMRO 2012". PMID:23142147

  6. Below knee prosthetic socket designs and suspension systems.

    Science.gov (United States)

    Edwards, M L

    2000-08-01

    The prosthetic socket must act as a customized connection between the residual limb's surrounding tissues and the prosthetic components. The socket must be designed to control weight bearing, suspension, and ambulation stability. When making a below-the-knee socket, the prosthetist attempts to maximize loading and minimize displacements, such as vertical, transverse, or rotational. This article discusses the engineering designs or shapes of the two basic forms of below-the-knee prosthetic sockets used today.

  7. Mandibular Overdentures Retained by Two Implants : 10-Year Results from a Crossover Clinical Trial Comparing Ball-Socket and Bar-Clip Attachments

    NARCIS (Netherlands)

    Cune, Marco; Burgers, Mark; van Kampen, Frits; de Putter, Cornelis; van der Bilt, Andries

    2010-01-01

    Purpose: The aim of this study was to evaluate patient satisfaction and clinical and prosthetic outcomes of two-implant mandibular overdenture treatment with different attachment types after 10 years of function. Materials and Methods: In a crossover clinical trial, 18 edentulous subjects with compl

  8. Finite element modeling of the contact interface between trans-tibial residual limb and prosthetic socket.

    Science.gov (United States)

    Lee, Winson C C; Zhang, Ming; Jia, Xiaohong; Cheung, Jason T M

    2004-10-01

    Finite element method has been identified as a useful tool to understand the load transfer mechanics between a residual limb and its prosthetic socket. This paper proposed a new practical approach in modeling the contact interface with consideration of the friction/slip conditions and pre-stresses applied on the limb within a rectified socket. The residual limb and socket were modeled as two separate structures and their interactions were simulated using automated contact methods. Some regions of the limb penetrated into the socket because of socket modification. In the first step of the simulation, the penetrated limb surface was moved onto the inner surface of the socket and the pre-stresses were predicted. In the subsequent loading step, pre-stresses were kept and loadings were applied at the knee joint to simulate the loading during the stance phase of gait. Comparisons were made between the model using the proposed approach and the model having an assumption that the shape of the limb and the socket were the same which ignored pre-stress. It was found that peak normal and shear stresses over the regions where socket undercuts were made reduced and the stress values over other regions raised in the model having the simplifying assumption.

  9. Socket Interface Pressure and Amputee Reported Outcomes for Comfortable and Uncomfortable Conditions of Patellar Tendon Bearing Socket: A Pilot Study.

    Science.gov (United States)

    Safari, Mohammad Reza; Tafti, Nahid; Aminian, Gholamreza

    2015-01-01

    The objectives of the current study were to compare intra-socket pressure differences between comfortable and uncomfortable socket conditions, and the usefulness of subject perception of satisfaction, activity limitations, and socket comfort in distinguishing between these two socket conditions. Five unilateral trans-tibial amputees took part in the study. They answered the Socket Comfort Score (SCS) and Trinity Amputation and Prosthetic Experience Scale (TAPES) questionnaires before the interface pressure (in standing and walking) was measured for the uncomfortable socket condition at five regions of the residual limb. Participants were then provided with a comfortable socket and wore it for two weeks. Participants who were satisfied with the socket fit after two weeks repeated the SCS and TAPES questionnaires and interface pressure measurements. The differences between the test results of the two conditions were not statistically significant, except for the interface pressure at the popliteal region during the early stance phase, TAPES socket fit subscale, and the SCS. Due to large variability of the data and the lack of statistical significance, no firm conclusion can be made on the possible relationship between the interface pressure values and the patient-reported outcomes of the two socket conditions. A larger sample size and longer acclimation period are required to locate significant differences.

  10. Single-Rooted Extraction Sockets: Classification and Treatment Protocol.

    Science.gov (United States)

    El Chaar, Edgar; Oshman, Sarah; Fallah Abed, Pooria

    2016-09-01

    Clinicians have many treatment techniques from which to choose when extracting a failing tooth and replacing it with an implant-supported restoration and when successful management of an extraction socket during the course of tooth replacement is necessary to achieve predictable and esthetic outcomes. This article presents a straightforward, yet thorough, classification for extraction sockets of single-rooted teeth and provides guidance to clinicians in the selection of appropriate and predictable treatment. The presented classification of extraction sockets for single-rooted teeth focuses on the topography of the extraction socket, while the protocol for treatment of each socket type factors in the shape of the remaining bone, the biotype, and the location of the socket whether it be in the mandible or maxilla. This system is based on the biologic foundations of wound healing and can help guide clinicians to successful treatment outcomes. PMID:27608197

  11. Dry Socket: Incidence, Clinical Features, and Predisposing Factors

    Directory of Open Access Journals (Sweden)

    Babatunde O. Akinbami

    2014-01-01

    Full Text Available Background. Dry socket is a global phenomenon. The purpose of the study was to investigate the incidence of dry socket in recent times in a Nigerian Tertiary Hospital. Methods. Patients who were referred for dental extractions were included in the study. The case files of patients were obtained and information retrieved included biodata, indication for extraction, number and type of teeth extracted, oral hygiene status, compliance to oral hygiene instructions, and development of dry socket. Results. One thousand, one hundred and eighty two patients with total of 1362 teeth extracted during the 4-year period of the study were analyzed, out of which 1.4% teeth developed dry socket. The mean age (SD was 35.2 (16.0 years. Most of the patients who presented with dry socket were in the fourth decade of life. Mandibular teeth were affected more than maxillary teeth. Molars were more affected. Retained roots and third molars were conspicuous in the cases with dry socket. Conclusion. The incidence of dry socket in our centre was lower than previous reports. Oral hygiene status, lower teeth, and female gender were significantly associated with development of dry socket. Treatment with normal saline irrigation and ZnO eugenol dressings allowed relief of the symptoms.

  12. Loopholes in Secure Socket layer and Sniffing

    Directory of Open Access Journals (Sweden)

    Amit Mishra

    2011-05-01

    Full Text Available Network sniffing was considered as a major threat to network and web application. Every device connected to the Ethernet-network receives all the data that is passed on the segment. By default the network card processes only data that is addressed to it. However listening programs turn network card in a mode of reception of all packets – called promiscuous mode. So, a sniffer is a special program or piece of code that put the Network Interface Card (NIC in the promiscuous mode. When NIC works in promiscuous mode, the user of that system can steal all the data including password etc. without generating any traffic. Any network system running the sniffer can see all the data movement over the network. Many sniffers like wireshark, Cain & Abel, ethersniff etc. are available at no cost on the internet. There are many proposed solutions are available for the detection of network sniffing including antisniff [1], SnifferWall [2], Sniffer Detector [3] etc. but any solution does not guarantee full security. Due to this reason many new techniques were developed including secure socket layer (https, one time password etc. but now there are some techniques that can be used to sniff this secure data. In this paper we are discussing different aspects of sniffing, methods to sniff data over secure socket network and detection of sniffer. The paper describes all the technical details and methods to perform this task.

  13. An experimental comparative study between polypropylene and laminated lower limb prosthetic socket

    Directory of Open Access Journals (Sweden)

    .Haider F. Neama, M.Sc

    2007-01-01

    Full Text Available Most researchers concentrate their studies on the design, stress and pressure distributions of the prosthetic socket. A little attention is considered for the stiffness of the various materials of the prosthetic sockets. Prosthetic laminated sockets in Iraq are costly to be manufactured while polypropylene socket is relatively cheap in comparing with the laminates. Experimental study is conducted to compare the stiffness of five prosthetic sockets made of different materials. Compression, three point flexural and tensile tests are implemented by the Testometric machine. The laminate sockets give better results in compression than polypropylene. Polypropylene gives good results in bending compared with the laminate sockets. When the socket loads are mainly in compression i.e. the low activity level patients, it seems that any of the tested sockets could be used, however, when the load will be not only in compression but in flexion as well i.e. high activity patients, socket No.1 and 5 could be used

  14. Review of the Socket Design and Interface Pressure Measurement for Transtibial Prosthesis

    OpenAIRE

    Gh. Pirouzi; Abu Osman, N. A.; Eshraghi, A.; Ali, S; H. Gholizadeh; W.A.B. Wan Abas

    2014-01-01

    Socket is an important part of every prosthetic limb as an interface between the residual limb and prosthetic components. Biomechanics of socket-residual limb interface, especially the pressure and force distribution, have effect on patient satisfaction and function. This paper aimed to review and evaluate studies conducted in the last decades on the design of socket, in-socket interface pressure measurement, and socket biomechanics. Literature was searched to find related keywords with trans...

  15. Happy Balls, Unhappy Balls, and Newton's Cradle

    Science.gov (United States)

    Kagan, David

    2010-01-01

    The intricacies of Newton's Cradle are well covered in the literature going as far back as the time of Newton! These discussions generally center on the highly elastic collisions of metal spheres. Thanks to the invention of happy and unhappy balls, you can build and study the interaction of less elastic systems (see Fig. 1).

  16. Investigation on the Dynamic Performance of the Tripod-Ball Sliding Joint with Clearance in a CRANK-SLIDER Mechanism. Part 1. Theoretical and Experimental Results

    Science.gov (United States)

    JIA, X.; JIN, D.; JI, L.; ZHANG, J.

    2002-05-01

    Clearance is inevitable in the kinematic joints of mechanisms. In this paper, the dynamic behavior of a crank-slider mechanism with clearance in its tripod-ball sliding joint is investigated theoretically and experimentally. The mathematical model of this new-type of joint is established, and the new concepts of basal system and active system are put forward. Based on the mode-change criterion established in this paper, the consistent equations of motion in full-scale are derived by using Kane method. The experimental rig was set up to measure the effects of the clearance on the dynamic response. The dynamic responses including additional motion, input torque and acceleration have been obtained, and the effects of the clearance size and driving speed have also been investigated by both analytical and experimental means. Corresponding experimental studies verify the theoretical results satisfactorily.

  17. Low-Friction, High-Stiffness Joint for Uniaxial Load Cell

    Science.gov (United States)

    Lewis, James L.; Le, Thang; Carroll, Monty B.

    2007-01-01

    A universal-joint assembly has been devised for transferring axial tension or compression to a load cell. To maximize measurement accuracy, the assembly is required to minimize any moments and non-axial forces on the load cell and to exhibit little or no hysteresis. The requirement to minimize hysteresis translates to a requirement to maximize axial stiffness (including minimizing backlash) and a simultaneous requirement to minimize friction. In practice, these are competing requirements, encountered repeatedly in efforts to design universal joints. Often, universal-joint designs represent compromises between these requirements. The improved universal-joint assembly contains two universal joints, each containing two adjustable pairs of angular-contact ball bearings. One might be tempted to ask why one could not use simple ball-and-socket joints rather than something as complex as universal joints containing adjustable pairs of angularcontact ball bearings. The answer is that ball-and-socket joints do not offer sufficient latitude to trade stiffness versus friction: the inevitable result of an attempt to make such a trade in a ball-and-socket joint is either too much backlash or too much friction. The universal joints are located at opposite ends of an axial subassembly that contains the load cell. The axial subassembly includes an axial shaft, an axial housing, and a fifth adjustable pair of angular-contact ball bearings that allows rotation of the axial housing relative to the shaft. The preload on each pair of angular-contact ball bearings can be adjusted to obtain the required stiffness with minimal friction, tailored for a specific application. The universal joint at each end affords two degrees of freedom, allowing only axial force to reach the load cell regardless of application of moments and non-axial forces. The rotational joint on the axial subassembly affords a fifth degree of freedom, preventing application of a torsion load to the load cell.

  18. Shallow Inferior Conjunctival Fornix in Contracted Socket and Anophthalmic Socket Syndrome: A Novel Technique to Deepen the Fornix Using Fascia Lata Strips

    Directory of Open Access Journals (Sweden)

    Mohamed F. K. Ibrahiem

    2016-01-01

    Full Text Available Purpose. To evaluate a new surgical technique using fascia lata to deepen the shallow inferior conjunctival fornix in contracted socket and anophthalmic socket syndrome. Methods. A prospective controlled study in which 24 sockets of 24 patients who were unable to wear and retain their ocular prosthesis due to shallow inferior fornix were enrolled and categorized into anophthalmic socket syndromes (9 patients and contracted sockets (15 patients. Another 24 patients who underwent evisceration or enucleation with healthy sockets and can wear and retain their prosthesis comfortably were chosen as a control group. Deepening of the fornix was performed using fascia lata strips under general anesthesia. Central depth of the inferior fornix was measured preoperatively and postoperatively. Results. A statistically significant improvement of the postoperative central inferior fornix depth was reported which was marked in anophthalmic subgroup. 100% of anophthalmic sockets and 93.3% of contracted sockets achieved satisfactory results during the follow-up period with no postoperative lower eyelid malposition or obvious skin scar. Conclusion. Fascia lata technique is a new alternative and effective procedure to deepen the shallow inferior fornix that can be used in moderate to severe contracted sockets or anophthalmic socket syndrome with minimal lower eyelid or socket complications.

  19. Study on solder joint reliability of ceramic ball grid array component based on design of experiment method

    Institute of Scientific and Technical Information of China (English)

    Wu Zhaohua; Huang Chunyue; Zhou Dejian

    2006-01-01

    Four process parameters, pad diameter, stencil thickness, ball diameter and stand-off were chosen as four control factors.By using an L25 ( 56 ) orthogonal array the ceramic ball grid array ( CBGA ) solder joints which have 25 different combinations of process parameters were designed.The numerical models of all the 25 CBGA solder joints were developed using the Surface Evolver.Utilizing the surface coordinate exported from the 25 CBGA solder joints numerical models, the finite element analysis models were set up and the nonlinear finite element analysis of the CBGA solder joints under thermal cycles were performed by ANSYS.The thermal fatigne life of CBGA solder joint was calculated using Coffin-Manson equation.Based on the calculated thermal fatigue life results, the range analysis and the variance analysis were performed.The results show that the fatigue life of CBGA solder joint is affected by the pad diameter, the stencil thickness, the ball diameter and the standoff in a descending order, the best combination of process parameters results in the longest fatigue life is 0.07 mm stand-off,0.125 mm stencil thickness of, 0.85 mm ball diameter and 0.89 mm pad diameter.With 95% confidence the pad diameter has a significant effect on the reliability of CBGA solder joints whereas the stand-off, the stencil thickness and the ball diameter have little effect on the reliability of CBGA solder joints.

  20. Computer-aided design and manufacture of an above-knee amputee socket.

    Science.gov (United States)

    Torres-Moreno, R; Saunders, C G; Foort, J; Morrison, J B

    1991-01-01

    This paper describes the initial test results obtained from a newly developed computer-aided socket design (CASD) and manufacturing (CASM) process for above-knee amputees. Anthropometric measures taken from an amputee provided input information to a CASD system. Using these measurements, data from a reference shape library stored in the computer were selected and modified to create a unique socket shape reflecting the particular characteristics of the amputation stump. The resultant shape was produced as a 'primitive' test socket by a CASM process. Numerical shape data were then transferred to a CNC milling machine to construct a negative cast, from which the primitive socket was produced by a vacuum-forming procedure. The resultant primitive socket shape was fitted and the amputee was able to load the socket without discomfort. Some shape discrepancies were identified and the shape data were modified interactively by the CASD system to create a final socket shape. The final socket shape was manufactured and worn by the amputee during a 35 min walking trial. Subjective evaluation was that the socket provided comfort and control comparable with that of the conventional socket, and proved to be acceptable to the amputee. This was followed by a 2-month home trial which was also successful. The CASD socket shapes were compared numerically in area, shape and volume with data taken from the original socket worn by the amputee, a new socket made by conventional methods and a topographic model of the amputation stump. The final CASD socket shape compared favourably with that of a socket manufactured by conventional methods.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2002669

  1. Spherical Joint Piston and Connecting Rod Developed

    Science.gov (United States)

    1996-01-01

    Under an interagency agreement with the Department of Energy, the NASA Lewis Research Center manages a Heavy-Duty Diesel Engine Technology (HDET) research program. The overall program objectives are to reduce fuel consumption through increased engine efficiency, reduce engine exhaust emissions, and provide options for the use of alternative fuels. The program is administered with a balance of research contracts, university research grants, and focused in-house research. The Cummins Engine Company participates in the HDET program under a cost-sharing research contract. Cummins is researching and developing in-cylinder component technologies for heavy-duty diesel engines. An objective of the Cummins research is to develop technologies for a low-emissions, 55-percent thermal efficiency (LE-55) engine. The best current-production engines in this class achieve about 46-percent thermal efficiency. Federal emissions regulations are driving this technology. Regulations for heavy duty diesel engines were tightened in 1994, more demanding emissions regulations are scheduled for 1998, and another step is planned for 2002. The LE-55 engine emissions goal is set at half of the 1998 regulation level and is consistent with plans for 2002 emissions regulations. LE-55 engine design requirements to meet the efficiency target dictate a need to operate at higher peak cylinder pressures. A key technology being developed and evaluated under the Cummins Engine Company LE-55 engine concept is the spherical joint piston and connecting rod. Unlike conventional piston and connecting rod arrangements which are joined by a pin forming a hinged joint, the spherical joint piston and connecting rod use a ball-and-socket joint. The ball-and-socket arrangement enables the piston to have an axisymmetric design allowing rotation within the cylinder. The potential benefits of piston symmetry and rotation are reduced scuffing, improved piston ring sealing, improved lubrication, mechanical and thermal

  2. Transfemoral sockets with vacuum-assisted suspension comparison of hip kinematics, socket position, contact pressure, and preference: Ischial containment versus brimless

    OpenAIRE

    Jason T. Kahle, MSMS, CPO, FAAOP; M. Jason Highsmith, PT, DPT, PhD, CP, FAAOP

    2013-01-01

    The objective of this study was to investigate the effect of brimless compared with ischial ramus containment (IRC) prosthetic sockets when using vacuum-assisted suspension (VAS) on persons with a unilateral transfemoral amputation (TFA). A randomized crossover design with a 2 d accommodation was used. People with unilateral TFA (n = 9 analyzed) were enrolled. Interventions were IRC VAS and brimless VAS sockets. Main outcome measures included coronal hip angle and vertical and lateral socket ...

  3. Life Prediction of Ball Grid Array Soldered Joints under Thermal Cycling Loading by Fracture Mechanics Method

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Fatigue crack propagation life of ball grid array (BGA) soldered joints during thermal cycling loading was investigated by fracture mechanics approach using finite element analysis. The relationships between the strain energy release rate (G) and crack size (α), thermal cycle numbers (N) can be derived. Based on the relationships, fatigue life of the soldered joints was determined. The results showed that crack propagation life was higher than crack initiation life. Therefore, it appears that it is more appropriate to predict the fatigue life of soldered joints using the fracture mechanics method.

  4. Load transfer mechanics between trans-tibial prosthetic socket and residual limb--dynamic effects.

    Science.gov (United States)

    Jia, Xiaohong; Zhang, Ming; Lee, Winson C C

    2004-09-01

    The effects of inertial loads on the interface stresses between trans-tibial residual limb and prosthetic socket were investigated. The motion of the limb and prosthesis was monitored using a Vicon motion analysis system and the ground reaction force was measured by a force platform. Equivalent loads at the knee joint during walking were calculated in two cases with and without consideration of the material inertia. A 3D nonlinear finite element (FE) model based on the actual geometry of residual limb, internal bones and socket liner was developed to study the mechanical interaction between socket and residual limb during walking. To simulate the friction/slip boundary conditions between the skin and liner, automated surface-to-surface contact was used. The prediction results indicated that interface pressure and shear stress had the similar double-peaked waveform shape in stance phase. The average difference in interface stresses between the two cases with and without consideration of inertial forces was 8.4% in stance phase and 20.1% in swing phase. The maximum difference during stance phase is up to 19%. This suggests that it is preferable to consider the material inertia effect in a fully dynamic FE model.

  5. Modeling and Preliminary Testing Socket-Residual Limb Interface Stiffness of Above-Elbow Prostheses

    OpenAIRE

    Sensinger, Jonathon W.; Weir, Richard F. ff.

    2008-01-01

    The interface between the socket and residual limb can have a significant effect on the performance of a prosthesis. Specifically, knowledge of the rotational stiffness of the socket-residual limb (S-RL) interface is extremely useful in designing new prostheses and evaluating new control paradigms, as well as in comparing existing and new socket technologies. No previous studies, however, have examined the rotational stiffness of S-RL interfaces. To address this problem, a math model is compa...

  6. Review of the Socket Design and Interface Pressure Measurement for Transtibial Prosthesis

    Directory of Open Access Journals (Sweden)

    Gh. Pirouzi

    2014-01-01

    Full Text Available Socket is an important part of every prosthetic limb as an interface between the residual limb and prosthetic components. Biomechanics of socket-residual limb interface, especially the pressure and force distribution, have effect on patient satisfaction and function. This paper aimed to review and evaluate studies conducted in the last decades on the design of socket, in-socket interface pressure measurement, and socket biomechanics. Literature was searched to find related keywords with transtibial amputation, socket-residual limb interface, socket measurement, socket design, modeling, computational modeling, and suspension system. In accordance with the selection criteria, 19 articles were selected for further analysis. It was revealed that pressure and stress have been studied in the last decaeds, but quantitative evaluations remain inapplicable in clinical settings. This study also illustrates prevailing systems, which may facilitate improvements in socket design for improved quality of life for individuals ambulating with transtibial prosthesis. It is hoped that the review will better facilitate the understanding and determine the clinical relevance of quantitative evaluations.

  7. Review of the socket design and interface pressure measurement for transtibial prosthesis.

    Science.gov (United States)

    Pirouzi, Gh; Abu Osman, N A; Eshraghi, A; Ali, S; Gholizadeh, H; Wan Abas, W A B

    2014-01-01

    Socket is an important part of every prosthetic limb as an interface between the residual limb and prosthetic components. Biomechanics of socket-residual limb interface, especially the pressure and force distribution, have effect on patient satisfaction and function. This paper aimed to review and evaluate studies conducted in the last decades on the design of socket, in-socket interface pressure measurement, and socket biomechanics. Literature was searched to find related keywords with transtibial amputation, socket-residual limb interface, socket measurement, socket design, modeling, computational modeling, and suspension system. In accordance with the selection criteria, 19 articles were selected for further analysis. It was revealed that pressure and stress have been studied in the last decaeds, but quantitative evaluations remain inapplicable in clinical settings. This study also illustrates prevailing systems, which may facilitate improvements in socket design for improved quality of life for individuals ambulating with transtibial prosthesis. It is hoped that the review will better facilitate the understanding and determine the clinical relevance of quantitative evaluations.

  8. Prosthetic sockets stabilized by alternating areas of tissue compression and release

    Directory of Open Access Journals (Sweden)

    Randall D. Alley, CP, LP

    2011-07-01

    Full Text Available A prosthetist makes a conventional socket by wrapping plaster bandage around the residual limb and using the resulting shell to create a positive model. After he or she modifies the plaster, it is used to create a laminated socket. Such sockets are almost perfect cylinders that encapsulate the limb. The bone is centered in soft, compressible tissue that must move aside before the bone can push against the socket to transmit force or torque to the prosthesis. In a compression/release stabilized (CRS socket, three or more longitudinal depressions compress and displace tissue between the socket wall and the bone to reduce lost motion when the bone is moved with respect to the socket. Release areas between depressions are opened to accommodate displaced tissue. Without these openings provided, the CRS socket will not function as intended. Often, the release areas of compression are the struts of a carbon-fiber frame, and the regions between struts are left open. A frame with openings may be modified by the prosthetist adding a thin membrane fully surrounding the limb but allowing the membrane and underlying tissue to enter the release openings. The membrane may contain electrodes, and it may constitute a roll-on liner that helps suspend the prosthesis. We introduce three socket designs: transradial, transfemoral, and transhumeral.

  9. Prosthetic sockets stabilized by alternating areas of tissue compression and release.

    Science.gov (United States)

    Alley, Randall D; Williams, T Walley; Albuquerque, Matthew J; Altobelli, David E

    2011-01-01

    A prosthetist makes a conventional socket by wrapping plaster bandage around the residual limb and using the resulting shell to create a positive model. After he or she modifies the plaster, it is used to create a laminated socket. Such sockets are almost perfect cylinders that encapsulate the limb. The bone is centered in soft, compressible tissue that must move aside before the bone can push against the socket to transmit force or torque to the prosthesis. In a compression/release stabilized (CRS) socket, three or more longitudinal depressions compress and displace tissue between the socket wall and the bone to reduce lost motion when the bone is moved with respect to the socket. Release areas between depressions are opened to accommodate displaced tissue. Without these openings provided, the CRS socket will not function as intended. Often, the release areas of compression are the struts of a carbon-fiber frame, and the regions between struts are left open. A frame with openings may be modified by the prosthetist adding a thin membrane fully surrounding the limb but allowing the membrane and underlying tissue to enter the release openings. The membrane may contain electrodes, and it may constitute a roll-on liner that helps suspend the prosthesis. We introduce three socket designs: transradial, transfemoral, and transhumeral.

  10. Comparison of CAD-CAM and hand made sockets for PTB prostheses.

    Science.gov (United States)

    Köhler, P; Lindh, L; Netz, P

    1989-04-01

    The aim of the present study was to compare sockets for below-knee (BK) prostheses made by Computer Aided Design-Computer Aided Manufacture (CAD-CAM) to those made by hand. The patients in the study were provided with two prostheses each, which apart from the sockets, were identical. One socket was made by the CAD-CAM technique developed at the Bioengineering Centre, Roehampton, University College London and one was made by hand at the OT-Centre, Stockholm, Sweden. The results were based on investigation of eight unilateral below-knee amputees evaluating their own sockets by Visual Analogous Scale with respect to comfort, pressure, and pain. The sockets were evaluated on seven occasions, at two tests, on delivery, after use every second day for six days and every second week for two weeks. All CAD-CAM sockets except one had to be changed once as compared to the hand made of which only two had to be changed. As to comfort it could not be demonstrated that there was any significant difference between the two types of sockets and both types were well accepted by all patients. Differences in pressure and pain were rarely reported. There were obvious differences between the two types of socket with respect to height, width, and inner surface configuration. The authors feel that CAD-CAM will in the near future be an excellent tool for design and manufacture of prosthetic sockets.

  11. Design of Socket Based on Intelligent Control and Energy Management

    Directory of Open Access Journals (Sweden)

    Jiang Feng

    2015-10-01

    Full Text Available Smart home is one of the main applications of internet of things, and it will realize the intellectualization of household. Smart socket is part of the smart home, which can be controlled remotely by power supplied, monitor utilization condition, communication network and other functions. This article mainly introduces the intelligent electrical outlet of each hardware modules; software part mainly analyzes the socket’s communication mechanism, and the electricity consumption of collected power statistics through diagrams to feedback through wireless communication. Things achieved in an environment of communication between the user and the smart power outlet timely feedback to the user, so as to achieve energy-saving purposes.

  12. Distributed Object-Oriented Architectures Sockets, Java RMI and CORBA

    CERN Document Server

    Stepisnik, Josef

    2007-01-01

    This document intends to offer a detailed discussion of selected distributed object-oriented architectures at conceptual level.The first part of the discussion offers a comprehensive overview of the Socket architecture in Java 2 and Berkeley UNIX and the distributed object model of Java Remote Method Invocation and the Common Object Request Broker Architecture.The second part concludes the discussion with a comparative study of selected features with emphasis on the Common Object Request Broker Architecture and Java Remote Method Invocation.Major Issues Includeˇ The TCP/IP Pro

  13. Rehabilitation of an Infected Eye with an Acrylic Ball Implant and a Custom made Scleral Ocular Prosthesis.

    Science.gov (United States)

    Anantharaju, Abhilash; Kamath, Giridhar; Rao K, Suhas; Naik, Deepak S

    2013-09-01

    This clinical report describes the prosthetic rehabilitation of a patient with corneal abscess with endophthalmitis of the left eye. Infection with a history of trauma resulted in loss of vision but with intact eye ball movements. Cornea excising evisceration was carried out following placement of poly(methyl methacrylate) ocular ball implant. Later custom made scleral prosthesis was fabricated to maintain functional integrity of the socket and to satisfy patient's aesthetic needs.

  14. Finite element analysis of the contact interface between trans-femoral stump and prosthetic socket.

    Science.gov (United States)

    Zhang, Linlin; Zhu, Ming; Shen, Ling; Zheng, Feng

    2013-01-01

    Transfemoral amputees need prosthetic devices after amputation surgery, and the interface pressure between the residual limb and prosthetic socket has a significant effect on an amputee's satisfaction and comfort. The purpose of this study was to build a nonlinear finite element model to investigate the interface pressure between the above-knee residual limb and its prosthetic socket. The model was three-dimensional (3D) with consideration of nonlinear boundary conditions. Contact analysis was used to simulate the friction conditions between skin and the socket. The normal stresses up to 80.57 kPa at the distal end of the soft tissue. The longitudinal and circumferential shear stress distributions at the limb-socket interface were also simulated. This study explores the influences of load transfer between trans-femoral residual limb and its prosthetic socket.

  15. Panenka-umělecký artefakt, Design panenky ball jointed doll

    OpenAIRE

    RATSCHMANOVÁ, Lucie

    2012-01-01

    The theme of this work is doll as a toy, collectible art and artifact. The theoretical part describes the historical development of dolls. It refers the phenomenon of BJD, ball jointed dolls. These dolls fall under the art doll, that is why I present the most important creators of these art dolls. Art dolls are created in different genres, one of them is fantasy, so I explain possible alternatives in the name and description. The practical part deals with the design BJD inspired by fantasy li...

  16. Transfemoral sockets with vacuum-assisted suspension comparison of hip kinematics, socket position, contact pressure, and preference: ischial containment versus brimless.

    Science.gov (United States)

    Kahle, Jason T; Highsmith, M Jason

    2013-01-01

    The objective of this study was to investigate the effect of brimless compared with ischial ramus containment (IRC) prosthetic sockets when using vacuum-assisted suspension (VAS) on persons with a unilateral transfemoral amputation (TFA). A randomized crossover design with a 2 d accommodation was used. People with unilateral TFA (n = 9 analyzed) were enrolled. Interventions were IRC VAS and brimless VAS sockets. Main outcome measures included coronal hip angle and vertical and lateral socket movement as measured by X-ray, skin pressure measured by Tekscan, and preference measured subjectively. The brimless design was statistically equivalent to IRC in all measured coronal hip angles and vertical and lateral socket displacement. The peak/stance mean pressure in the medial proximal aspect of the socket was 322 mmHg in the IRC compared with 190 mmHg in the brimless condition. Except for medial proximal pressure, no other measures reached statistical significance. All subjects reported the brimless design to be more comfortable than the IRC in short-term preference. Brimless VAS socket design may be a clinically viable choice for people with TFA.

  17. Transfemoral sockets with vacuum-assisted suspension comparison of hip kinematics, socket position, contact pressure, and preference: Ischial containment versus brimless

    Directory of Open Access Journals (Sweden)

    Jason T. Kahle, MSMS, CPO, FAAOP

    2013-12-01

    Full Text Available The objective of this study was to investigate the effect of brimless compared with ischial ramus containment (IRC prosthetic sockets when using vacuum-assisted suspension (VAS on persons with a unilateral transfemoral amputation (TFA. A randomized crossover design with a 2 d accommodation was used. People with unilateral TFA (n = 9 analyzed were enrolled. Interventions were IRC VAS and brimless VAS sockets. Main outcome measures included coronal hip angle and vertical and lateral socket movement as measured by X-ray, skin pressure measured by Tekscan, and preference measured subjectively. The brimless design was statistically equivalent to IRC in all measured coronal hip angles and vertical and lateral socket displacement. The peak/stance mean pressure in the medial proximal aspect of the socket was 322 mmHg in the IRC compared with 190 mmHg in the brimless condition. Except for medial proximal pressure, no other measures reached statistical significance. All subjects reported the brimless design to be more comfortable than the IRC in short-term preference. Brimless VAS socket design may be a clinically viable choice for people with TFA.

  18. Transfemoral sockets with vacuum-assisted suspension comparison of hip kinematics, socket position, contact pressure, and preference: ischial containment versus brimless.

    Science.gov (United States)

    Kahle, Jason T; Highsmith, M Jason

    2013-01-01

    The objective of this study was to investigate the effect of brimless compared with ischial ramus containment (IRC) prosthetic sockets when using vacuum-assisted suspension (VAS) on persons with a unilateral transfemoral amputation (TFA). A randomized crossover design with a 2 d accommodation was used. People with unilateral TFA (n = 9 analyzed) were enrolled. Interventions were IRC VAS and brimless VAS sockets. Main outcome measures included coronal hip angle and vertical and lateral socket movement as measured by X-ray, skin pressure measured by Tekscan, and preference measured subjectively. The brimless design was statistically equivalent to IRC in all measured coronal hip angles and vertical and lateral socket displacement. The peak/stance mean pressure in the medial proximal aspect of the socket was 322 mmHg in the IRC compared with 190 mmHg in the brimless condition. Except for medial proximal pressure, no other measures reached statistical significance. All subjects reported the brimless design to be more comfortable than the IRC in short-term preference. Brimless VAS socket design may be a clinically viable choice for people with TFA. PMID:24458964

  19. Deformities and injuries of the ankle joint in children and adolescents

    International Nuclear Information System (INIS)

    Knowledge of the normal development of the ankle joint is mandatory to understand the mechanism of injuries in children and adolescents. Some fractures (juvenile Tillaux's or two-fragment triplane fracture) occur only within a particular period of growth, which is determined by the degree of epiphyseal fusion. Tarsal coalitions are the deformities seen most frequently. Special radiographic techniques must be applied for the diagnosis. Ball and socket joint, tibiotalar slant and Trevor's disease are rare deformities, each of which is associated with a pathognomonic radiographic pattern. Some typical joint deformities may be seen in patients with neuromuscular disease. This has to be considered when nothing else is found in the clincial history. (orig.)

  20. Socket welding method

    International Nuclear Information System (INIS)

    Upon joining of metal tubes having a same composition, a metal having a corrosion potential higher by from 50 to 300mV than that of the metal which constitutes the metal tube is disposed at the periphery of the joint portion of the metal tubes in order to improve corrosion resistance of the joint portion of pipelines in a plant such as a nuclear reactor. In a socket joint in which metal tubes having a greater outer diameter than the inner diameter of the other are fitted to each other at the joint portion, more remarkable effect can be obtained. This is because the area of the gap portion is greater than in the case of butt welding. Further, it is preferred that a metal having a corrosion potential greater by from 50 to 300mV than that of the metal tube is interposed at least to a portion of the overlapped portion of the tubes in order to prevent corrosion of the gap portion. Then, a carbon steel pipe weld-joint having sufficiently high resistance to temperature and pressure water SCC can be attained in a BWR reactor water circumstance, and the safety of the BWR can be ensured, as well as the working life of the reactor plant can be attained. (N.H.)

  1. Effect of alignment changes on sagittal and coronal socket reaction moment interactions in transtibial prostheses.

    Science.gov (United States)

    Kobayashi, Toshiki; Orendurff, Michael S; Zhang, Ming; Boone, David A

    2013-04-26

    Alignment is important for comfortable and stable gait of lower-limb prosthesis users. The magnitude of socket reaction moments in the multiple planes acting simultaneously upon the residual limb may be related to perception of comfort in individuals using prostheses through socket interface pressures. The aim of this study was to investigate the effect of prosthetic alignment changes on sagittal and coronal socket reaction moment interactions (moment-moment curves) and to characterize the curves in 11 individuals with transtibial amputation using novel moment-moment interaction parameters measured by plotting sagittal socket reaction moments versus coronal ones under various alignment conditions. A custom instrumented prosthesis alignment component was used to measure socket reaction moments during walking. Prosthetic alignment was tuned to a nominally aligned condition by a prosthetist, and from this position, angular (3° and 6° of flexion, extension, abduction or adduction of the socket) and translational (5mm and 10mm of anterior, posterior, medial or lateral translation of the socket) alignment changes were performed in either the sagittal or the coronal plane in a randomized manner. A total of 17 alignment conditions were tested. Coronal angulation and translation alignment changes demonstrated similar consistent changes in the moment-moment curves. Sagittal alignment changes demonstrated more complex changes compared to the coronal alignment changes. Effect of sagittal angulations and translations on the moment-moment curves was different during 2nd rocker (mid-stance) with extension malalignment appearing to cause medio-lateral instability. Presentation of coronal and sagittal socket reaction moment interactions may provide useful visual information for prosthetists to understand the biomechanical effects of malalignment of transtibial prostheses.

  2. How does adding and removing liquid from socket bladders affect residual-limb fluid volume?

    Directory of Open Access Journals (Sweden)

    Joan E. Sanders, PhD

    2013-08-01

    Full Text Available Adding and removing liquid from socket bladders is a means for people with limb loss to accommodate residual-limb volume change. We fit 19 people with transtibial amputation using their regular prosthetic socket with fluid bladders on the inside socket surface to undergo cycles of bladder liquid addition and removal. In each cycle, subjects sat, stood, and walked for 90 s with bladder liquid added, and then sat, stood, and walked for 90 s again with the bladder liquid removed. The amount of bladder liquid added was increased in each cycle. We used bioimpedance analysis to measure residual-limb fluid volume. Results showed that the preferred bladder liquid volume was 16.8 +/– 8.4 mL (mean +/– standard deviation, corresponding with 1.7% +/– 0.8% of the average socket volume between the bioimpedance voltage-sensing electrodes. Residual-limb fluid volume driven out of the residual limb when bladder liquid was added was typically not recovered upon subsequent bladder liquid removal. Of the 19 subjects, 15 experienced a gradual residual-limb fluid volume loss over the test session. Care should be taken when implementing adjustable socket technologies in people with limb loss. Reducing socket volume may accentuate residual-limb fluid volume loss.

  3. How does adding and removing liquid from socket bladders affect residual-limb fluid volume?

    Science.gov (United States)

    Sanders, Joan E; Cagle, John C; Harrison, Daniel S; Myers, Timothy R; Allyn, Kathryn J

    2013-01-01

    Adding and removing liquid from socket bladders is a means for people with limb loss to accommodate residual-limb volume change. We fit 19 people with transtibial amputation using their regular prosthetic socket with fluid bladders on the inside socket surface to undergo cycles of bladder liquid addition and removal. In each cycle, subjects sat, stood, and walked for 90 s with bladder liquid added, and then sat, stood, and walked for 90 s again with the bladder liquid removed. The amount of bladder liquid added was increased in each cycle. We used bioimpedance analysis to measure residual-limb fluid volume. Results showed that the preferred bladder liquid volume was 16.8 +/- 8.4 mL (mean +/- standard deviation), corresponding with 1.7% +/- 0.8% of the average socket volume between the bioimpedance voltage-sensing electrodes. Residual-limb fluid volume driven out of the residual limb when bladder liquid was added was typically not recovered upon subsequent bladder liquid removal. Of the 19 subjects, 15 experienced a gradual residual-limb fluid volume loss over the test session. Care should be taken when implementing adjustable socket technologies in people with limb loss. Reducing socket volume may accentuate residual-limb fluid volume loss.

  4. Prosthetic Rehabilitation Following Socket Reconstruction with Blair-Brown Graft and Conformer Therapy for Management of Severe Post-Enucleation Socket Syndrome--A Clinical Report.

    Science.gov (United States)

    Aggarwal, Himanshi; Singh, Saumyendra V; Kumar, Pradeep; Kumar Singh, Arun

    2015-06-01

    One of the most common tumors of the eye diagnosed in childhood is retinoblastoma, which mandates enucleation with adjunctive chemotherapy and radiotherapy to save the patient's life. The most common late enucleation complication is post-enucleation socket syndrome (PESS), which poses a management dilemma for the prosthodontist and surgeon, along with being a major esthetic concern for the patient. The reconstruction of such sockets is complex. The purpose of this clinical report is to describe the rehabilitation of such a pediatric patient with severe PESS. The patient was successfully rehabilitated by presurgical conformer therapy, socket reconstruction surgery with non-meshed intermediate split thickness skin graft (STSG)/Blair-Brown graft, and postsurgical conformer stent. This was followed by fabrication of a custom ocular prosthesis, to achieve favorable functional, physical, and psychological effects.

  5. Comparative analysis of use of porous orbital implant with mucus membrane graft and dermis fat graft as a primary procedure in reconstruction of severely contracted socket

    Directory of Open Access Journals (Sweden)

    Kasturi Bhattacharjee

    2014-01-01

    Full Text Available Purpose: The purpose of our study is to present a surgical technique of primary porous orbital ball implantation with overlying mucus membrane graft (MMG for reconstruction of severely contracted socket and to evaluate prosthesis retention and motility in comparison to dermis fat graft (DFG. Study Design: Prospective comparative study. Materials and Methods: A total of 24 patients of severe socket contracture (Grade 2-4 Krishna′s classification were subdivided into two groups, 12 patients in each group. In Group I, DFG have been used for reconstruction. In Group II, porous polyethylene implant with MMG has been used as a primary procedure for socket reconstruction. In Group I DFG was carried out in usual procedure. In case of Group II, vascularized scar tissues were separated 360° and were fashioned into four strips. A scleral capped porous polyethylene implant was placed in the intraconal space and four strips of scar tissue were secured to the scleral cap and extended part overlapped the implant to make a twofold barrier between the implant and MMG. Patients were followed-up as per prefixed proforma. Prosthesis motility and retention between the two groups were measured. Results: In Group I, four patients had recurrence of contracture with fall out of prosthesis. In Group II stable reconstruction was achieved in all the patients. In terms of prosthesis motility, maximum in Group I was 39.2% and Group II, was 59.3%. The difference in prosthesis retention (P = 0.001 and motility (P = 0.004 between the two groups was significant. Conclusion: Primary socket reconstruction with porous orbital implant and MMG for severe socket contracture is an effective method in terms of prosthesis motility and prosthesis retention.

  6. Radio-ulnar joint supinates around ball release during baseball fastball pitching.

    Science.gov (United States)

    Matsuo, Tomoyuki; Jinji, Tsutomu; Hirayama, Daisaku; Nasu, Daiki; Ozaki, Hiroki

    2016-06-01

    This study was conducted to determine whether a supination phase of the forearm exists around ball release (BRL), and, if present, to determine whether this supination is explained by a reaction force or by the body configuration required for this task. A 16-camera motion analysis system with a sampling frequency of 1,000 Hz recorded 20 healthy male semi-professional pitchers pitching from an indoor pitching mound. A short supination phase around BRL was confirmed for all participants in the current study. Correlation analyses revealed that the supination angle at BRL had significant relationships with several measurements of shoulder movement kinematics. Mechanical work analysis of the forearm's longitudinal axis revealed several variations in joint power curve and various patterns of mechanical work among the participants, suggesting that a reaction force originating from accelerating a ball might not be the main cause of supination. The raw data also were down-sampled to a sampling frequency of 250 Hz, to match previous studies and to investigate the discrepancy among previous studies concerning the existence of the supination phase. The experience of participants and methodological differences, such as the definition of BRL and the time-normalisation technique, influenced whether the supination phase was observed. PMID:27111583

  7. Stabilizing transpelvic prosthetic socket for a patient with spinal cord injury sustaining right partial hemipelvectomy and left hip disarticulation.

    Science.gov (United States)

    Nakanishi, Yoshie; Watanabe, Tetsuro; Ikeda, Atsushi; Wada, Futoshi; Hachisuka, Kenji

    2012-06-01

    A bucket-type transpelvic socket was fabricated for a man with paraplegia from spinal cord injury, who underwent right partial pelvic amputation and left hip disarticulation. His main problem was inability to sit due to asymmetrical pelvic shape. We prescribed a transpelvic prosthetic socket to enable him to sit again. The socket consisted of a dual structure: a hard frame and soft liner. The main features of the socket were redistribution of pressure to prevent recurrence of pressure ulcer, and a slightly backward tilt to maintain a comfortable sitting position. In addition, the socket had small air holes for ventilation; a big window in the abdominal area for management of stoma and cystostomy; and two straps for donning it independently. In addition, we confirmed the internal pressure distribution in the socket by a pressure mapping system to prevent reoccurrence of skin trouble. Finally, the patient regained independence in activities of daily living, including driving a car, after two months of rehabilitative training.

  8. Deformities and injuries of the ankle joint in children and adolescents. Missbildungen und Traumafolgen des kindlichen und jugendlichen Sprunggelenks

    Energy Technology Data Exchange (ETDEWEB)

    Erlemann, R. (Sankt-Johannes-Hospital, Duisburg (Germany, F.R.). Radiologische Klinik); Wuisman, P. (Muenster Univ. (Germany). Orthopaedische Klinik und Poliklinik (Huefferstiftung)); Just, A.; Peters, P.E. (Muenster Univ. (Germany, F.R.). Inst. fuer Klinische Radiologie)

    1991-12-01

    Knowledge of the normal development of the ankle joint is mandatory to understand the mechanism of injuries in children and adolescents. Some fractures (juvenile Tillaux's or two-fragment triplane fracture) occur only within a particular period of growth, which is determined by the degree of epiphyseal fusion. Tarsal coalitions are the deformities seen most frequently. Special radiographic techniques must be applied for the diagnosis. Ball and socket joint, tibiotalar slant and Trevor's disease are rare deformities, each of which is associated with a pathognomonic radiographic pattern. Some typical joint deformities may be seen in patients with neuromuscular disease. This has to be considered when nothing else is found in the clincial history. (orig.).

  9. Surface EMG and intra-socket force measurement to control a prosthetic device

    Science.gov (United States)

    Sanford, Joe; Patterson, Rita; Popa, Dan

    2015-06-01

    Surface electromyography (SEMG) has been shown to be a robust and reliable interaction method allowing for basic control of powered prosthetic devices. Research has shown a marked decrease in EMG-classification efficiency throughout activities of daily life due to socket shift and movement and fatigue as well as changes in degree of fit of the socket throughout the subject's lifetime. Users with the most severe levels of amputation require the most complex devices with the greatest number of degrees of freedom. Controlling complex dexterous devices with limited available inputs requires the addition of sensing and interaction modalities. However, the larger the amputation severity, the fewer viable SEMG sites are available as control inputs. Previous work reported the use of intra-socket pressure, as measured during wrist flexion and extension, and has shown that it is possible to control a powered prosthetic device with pressure sensors. In this paper, we present data correlations of SEMG data with intra-socket pressure data. Surface EMG sensors and force sensors were housed within a simulated prosthetic cuff fit to a healthy-limbed subject. EMG and intra-socket force data was collected from inside the cuff as a subject performed pre-defined grip motions with their dominant hand. Data fusion algorithms were explored and allowed a subject to use both intra-socket pressure and SEMG data as control inputs for a powered prosthetic device. This additional input modality allows for an improvement in input classification as well as information regarding socket fit through out activities of daily life.

  10. Fluid Mechanics of Cricket and Tennis Balls

    Science.gov (United States)

    Mehta, Rabindra D.

    2009-11-01

    Aerodynamics plays a prominent role in defining the flight of a ball that is struck or thrown through the air in almost all ball sports. The main interest is in the fact that the ball can often deviate from its initial straight path, resulting in a curved, or sometimes an unpredictable, flight path. It is particularly fascinating that that not all the parameters that affect the flight of a ball are always under human influence. Lateral deflection in flight, commonly known as swing, swerve or curve, is well recognized in cricket and tennis. In tennis, the lateral deflection is produced by spinning the ball about an axis perpendicular to the line of flight, which gives rise to what is commonly known as the Magnus effect. It is now well recognized that the aerodynamics of sports balls are strongly dependent on the detailed development and behavior of the boundary layer on the ball's surface. A side force, which makes a ball curve through the air, can also be generated in the absence of the Magnus effect. In one of the cricket deliveries, the ball is released with the seam angled, which trips the laminar boundary layer into a turbulent state on that side. The turbulent boundary layer separates relatively late compared to the laminar layer on the other side, thereby creating a pressure difference and hence side force. The fluid mechanics of a cricket ball become very interesting at the higher Reynolds numbers and this will be discussed in detail. Of all the round sports balls, a tennis ball has the highest drag coefficient. This will be explained in terms of the contribution of the ``fuzz" drag and how that changes with Reynolds number and ball surface wear. It is particularly fascinating that, purely through historical accidents, small disturbances on the ball surface, such as the stitching on cricket balls and the felt cover on tennis balls are all about the right size to affect boundary layer transition and development in the Reynolds numbers of interest. The fluid

  11. A pressure and shear sensor system for stress measurement at lower limb residuum/socket interface.

    Science.gov (United States)

    Laszczak, P; McGrath, M; Tang, J; Gao, J; Jiang, L; Bader, D L; Moser, D; Zahedi, S

    2016-07-01

    A sensor system for measurement of pressure and shear at the lower limb residuum/socket interface is described. The system comprises of a flexible sensor unit and a data acquisition unit with wireless data transmission capability. Static and dynamic performance of the sensor system was characterised using a mechanical test machine. The static calibration results suggest that the developed sensor system presents high linearity (linearity error ≤ 3.8%) and resolution (0.9 kPa for pressure and 0.2 kPa for shear). Dynamic characterisation of the sensor system shows hysteresis error of approximately 15% for pressure and 8% for shear. Subsequently, a pilot amputee walking test was conducted. Three sensors were placed at the residuum/socket interface of a knee disarticulation amputee and simultaneous measurements were obtained during pilot amputee walking test. The pressure and shear peak values as well as their temporal profiles are presented and discussed. In particular, peak pressure and shear of approximately 58 kPa and 27 kPa, respectively, were recorded. Their temporal profiles also provide dynamic coupling information at this critical residuum/socket interface. These preliminary amputee test results suggest strong potential of the developed sensor system for exploitation as an assistive technology to facilitate socket design, socket fit and effective monitoring of lower limb residuum health.

  12. Finite-element analysis to determine effect of monolimb flexibility on structural strength and interaction between residual limb and prosthetic socket.

    Science.gov (United States)

    Lee, Winson C C; Zhang, Ming; Boone, David A; Contoyannis, Bill

    2004-01-01

    Monolimb refers to a kind of transtibial prostheses having the socket and shank molded into one piece of thermoplastic material. One of its characteristics is that the shank is made of a material that can deform during walking, which can simulate ankle joint motion to some extent. Changes in shank geometry can alter the stress distribution within the monolimb and at the residual limb-socket interface and, respectively, affect the deformability and structural integrity of the prosthesis and comfort perceived by amputees. This paper describes the development of a finite-element model for the study of the structural behavior of monolimbs with different shank designs and the interaction between the limb and socket during walking. The von Mises stress distributions in monolimbs with different shank designs at different walking phases are reported. With the use of distortion energy theory, possible failure was predicted. The effect of the stiffness of the monolimb shanks on the stress distribution at the limb-socket interface was studied. The results show a trend--the peak stress applied to the limb was lowered as the shank stiffness decreased. This information is useful for future monolimb optimization.

  13. Some Mathematics and Physics of Ball Games.

    Science.gov (United States)

    Hughes, D. E.

    1985-01-01

    Gives examples on the applications of arithmetic, geometry, and some calculus, vector algebra, and mechanics to ball games. Suggestions for further interesting investigations are provided together with references to other articles and books on applications of mathematics and physics to ball games and sports in general. (JN)

  14. Developing RESTful services with JAX-RS 2.0, WebSockets, and JSON

    CERN Document Server

    Kalali, Masoud

    2013-01-01

    Written as an easy and practical guide, this book is a crash course on using JAX-RS 2.0, JSON, and WebSockets to develop RESTful services.Getting Started with Developing RESTful Web Services using JAX-RS 2.0, JSON, and WebSockets is a perfect reading source for application developers who are familiar with Java EE and are keen to understand the new HTML5-related functionality introduced in Java EE 7 to improve productivity. To take full advantage of this book, you need to be familiar with Java EE and have some basic understanding of using the GlassFish application server.

  15. Effect of Stiffness of Rolling Joints on the Dynamic Characteristic of Ball Screw Feed Systems in a Milling Machine

    Directory of Open Access Journals (Sweden)

    Dazhong Wang

    2015-01-01

    Full Text Available Dynamic characteristic of ball screw feed system in a milling machine is studied numerically in this work. In order to avoid the difficulty in determining the stiffness of rolling joints theoretically, a dynamic modeling method for analyzing the feed system is discussed, and a stiffness calculation method of the rolling joints is proposed based on the Hertz contact theory. Taking a 3-axis computer numerical control (CNC milling machine set ermined as a research object, the stiffness of its fixed joint between the column and the body together with the stiffness parameters of the rolling joints is evaluated according to the Takashi Yoshimura method. Then, a finite element (FE model is established for the machine tool. The correctness of the FE model and the stiffness calculation method of the rolling joints are validated by theoretical and experimental modal analysis results of the machine tool’s workbench. Under the two modeling methods of joints incorporating the stiffness parameters and rigid connection, a theoretical modal analysis is conducted for the CNC milling machine. The natural frequencies and modal shapes reveal that the joints’ dynamic characteristic has an important influence on the dynamic performance of a whole machine tool, especially for the case with natural frequency and higher modes.

  16. Effect of prosthetic gel liner thickness on gait biomechanics and pressure distribution within the transtibial socket

    Directory of Open Access Journals (Sweden)

    Erin Boutwell, MS

    2012-04-01

    Full Text Available Prosthetic gel liners are often prescribed for persons with lower-limb amputations to make the prosthetic socket more comfortable. However, their effects on residual limb pressures and gait characteristics have not been thoroughly explored. This study investigated the effects of gel liner thickness on peak socket pressures and gait patterns of persons with unilateral transtibial amputations. Pressure and quantitative gait data were acquired while subjects walked on liners of two different uniform thicknesses. Fibular head peak pressures were reduced (p = 0.04 with the thicker liner by an average of 26 +/– 21%, while the vertical ground reaction force (GRF loading peak increased 3 +/– 3% (p = 0.02. Most subjects perceived increased comfort within the prosthetic socket with the thicker liner, which may be associated with the reduced fibular head peak pressures. Additionally, while the thicker liner presumably increased comfort by providing a more compliant limb-socket interface, the higher compliance may have reduced force and vibration feedback to the residual limb and contributed to the larger vertical GRF loading peaks. We conclude that determining optimal gel liner thickness for a particular individual will require further investigations to better identify and understand the compromises that occur between user perception, residual-limb pressure distribution, and gait biomechanics.

  17. Effect of prosthetic gel liner thickness on gait biomechanics and pressure distribution within the transtibial socket.

    Science.gov (United States)

    Boutwell, Erin; Stine, Rebecca; Hansen, Andrew; Tucker, Kerice; Gard, Steven

    2012-01-01

    Prosthetic gel liners are often prescribed for persons with lower-limb amputations to make the prosthetic socket more comfortable. However, their effects on residual limb pressures and gait characteristics have not been thoroughly explored. This study investigated the effects of gel liner thickness on peak socket pressures and gait patterns of persons with unilateral transtibial amputations. Pressure and quantitative gait data were acquired while subjects walked on liners of two different uniform thicknesses. Fibular head peak pressures were reduced (p = 0.04) with the thicker liner by an average of 26 +/- 21%, while the vertical ground reaction force (GRF) loading peak increased 3 +/- 3% (p = 0.02). Most subjects perceived increased comfort within the prosthetic socket with the thicker liner, which may be associated with the reduced fibular head peak pressures. Additionally, while the thicker liner presumably increased comfort by providing a more compliant limb-socket interface, the higher compliance may have reduced force and vibration feedback to the residual limb and contributed to the larger vertical GRF loading peaks. We conclude that determining optimal gel liner thickness for a particular individual will require further investigations to better identify and understand the compromises that occur between user perception, residual-limb pressure distribution, and gait biomechanics.

  18. Rotating Boson Stars and Q-Balls

    CERN Document Server

    Kleihaus, B; List, M; Kleihaus, Burkhard; Kunz, Jutta; List, Meike

    2005-01-01

    We consider axially symmetric, rotating boson stars. Their flat space limits represent spinning Q-balls. We discuss their properties and determine their domain of existence. Q-balls and boson stars are stationary solutions and exist only in a limited frequency range. The coupling to gravity gives rise to a spiral-like frequency dependence of the boson stars. We address the flat space limit and the limit of strong gravitational coupling. For comparison we also determine the properties of spherically symmetric Q-balls and boson stars.

  19. Laboratory and clinical tests of a prototype pressure sensor for clincial assessment of prosthetic socket fit.

    Science.gov (United States)

    Polliack, A A; Craig, D D; Sieh, R C; Landsberger, S; Mcneal, D R

    2002-04-01

    Lower limb prosthetic socket fabrication is a highly refined process relying on the prosthetist's skill and experience. Despite their best efforts, patients often return with complications. Additionally, clinical application of technological advances for the quantification of biomechanical factors at the socket interface has not changed in practice. Measuring pressure levels at the stump/socket interface could provide valuable information in the process of prosthetic socket fabrication, fit and modification. This paper presents findings on the performance of a prototype capacitance pressure sensor designed for prosthetic socket use. Bench tests using compressed air were performed to measure accuracy, hysteresis and drift responses in both a flatbed chamber and a custom-modified pressure vessel. For the contoured testing, the sensors were placed on nine sites on a positive trans-tibial stump mould and enveloped with a silicone liner. Additionally, a preliminary clinical evaluation was performed with two trans-tibial amputee subjects at the nine sites during normal ambulation. Bench test results showed that the prototype capacitance sensor performed well in all categories, exhibiting a 2.42% (flatbed) and 9.96% (contoured) accuracy error, a 12.93% (flatbed) and 12.95% (contoured) hysteresis error, and a 4.40% (flatbed) and 6.20% (contoured) drift error. The clinical study showed that after three hours of continual use, no noticeable sensor drift occurred between pre and post-test calibration values. The results from this study were encouraging and the authors hope to conduct further laboratory and clinical trials to assess the influence of shear force and dynamic loading on sensor response.

  20. Effect of alignment changes on socket reaction moments during gait in transfemoral and knee-disarticulation prostheses: case series.

    Science.gov (United States)

    Kobayashi, Toshiki; Orendurff, Michael S; Boone, David A

    2013-09-27

    The alignment of a lower-limb prosthesis is critical to the successful prosthetic fitting and utilization by the wearer. Loads generated by the socket applied to the residual limb while walking are thought to be different in transfemoral and knee-disarticulation prostheses. The aim of this case series was to compare the socket reaction moments between transfemoral and knee-disarticulation prostheses and to investigate the effect of alignment changes on them. Two amputees, one with a transfemoral prosthesis and another with a knee-disarticulation prosthesis, participated in this study. A Smart Pyramid™ was used to measure socket reaction moments while walking under 9 selected alignment conditions; including nominally aligned, angle malalignments of 6° (flexion, extension, abduction and adduction) and translation malalignments of 15 mm (anterior, posterior, medial and lateral) of the socket relative to the foot. This study found that the pattern of the socket reaction moments was similar between transfemoral and knee-disarticulation prostheses. An extension moment in the sagittal plane and a varus moment in the coronal plane were dominant during stance under the nominally aligned condition. This study also demonstrated that alignment changes might have consistent effects on the socket reaction moments in transfemoral and knee-disarticulation prostheses. Extension and posterior translation of the socket resulted in increases in an extension moment, while abduction and lateral translation of the socket resulted in increases in a varus moment. The socket reaction moments may potentially serve as useful biomechanical parameters to evaluate alignment in transfemoral and knee-disarticulation prostheses.

  1. A Combined Surgical and Prosthetic Approach for the Successful Management of a Mutilated Eye Socket: A case report.

    Science.gov (United States)

    Prithviraj, D R; Khare, Sumit; Gupta, Anish; Shruthi, D P

    2010-04-01

    Facial disfigurement through the loss of an eye due to a road traffic accident can be devastating for the patient and may leave few options for an ophthalmologist, especially if the situation demands urgency. In the present case report, the patient had a major accident, which resulted in the severe disruption of the socket. The requirements of the prosthodontist regarding the morphology of the socket guided the ophthalmologist to undertake reconstructive surgery. The prosthesis was then fabricated such that both its longevity and the morphology of the socket were safe guarded.

  2. Walking Ability and Quality of Life in Subjects With Transfemoral Amputation: A Comparison of Osseointegration With Socket Prostheses.

    NARCIS (Netherlands)

    Meent, H. van de; Hopman, M.T.E.; Frolke, J.P.M.

    2013-01-01

    OBJECTIVE: To investigate walking ability and quality of life of osseointegrated leg prostheses compared with socket prostheses. DESIGN: Prospective case-control study. SETTING: University medical center. PARTICIPANTS: Subjects (N=22) with transfemoral amputation (1 bilateral) referred to our center

  3. Dolphin underwater bait-balling behaviors in relation to group and prey ball sizes.

    Science.gov (United States)

    Vaughn-Hirshorn, Robin L; Muzi, Elisa; Richardson, Jessica L; Fox, Gabriella J; Hansen, Lauren N; Salley, Alyce M; Dudzinski, Kathleen M; Würsig, Bernd

    2013-09-01

    We characterized dusky dolphin (Lagenorhynchus obscurus) feeding behaviors recorded on underwater video, and related behaviors to variation in prey ball sizes, dolphin group sizes, and study site (Argentina versus New Zealand, NZ). Herding behaviors most often involved dolphins swimming around the side or under prey balls, but dolphins in Argentina more often swam under prey balls (48% of passes) than did dolphins in NZ (34% of passes). This result may have been due to differences in group sizes between sites, since groups are larger in Argentina. Additionally, in NZ, group size was positively correlated with proportion of passes that occurred under prey balls (pdolphins in Argentina more often swam through prey balls (8% of attempts) than did dolphins in NZ (4% of attempts). This result may have been due to differences in prey ball sizes between sites, since dolphins fed on larger prey balls in Argentina (>74m(2)) than in NZ (maximum 33m(2)). Additionally, in NZ, dolphins were more likely to swim through prey balls to capture fish when they fed on larger prey balls (p=0.025).

  4. Implementing the WebSocket Protocol Based on Formal Modelling and Automated Code Generation

    DEFF Research Database (Denmark)

    Simonsen, Kent Inge; Kristensen, Lars Michael

    2014-01-01

    protocols. Furthermore, we perform formal verification of the CPN model prior to code generation, and test the implementation for interoperability against the Autobahn WebSocket test-suite resulting in 97% and 99% success rate for the client and server implementation, respectively. The tests show that the...... pragmatic annotations for automated code generation of protocol software. The contribution of this paper is an application of the approach as implemented in the PetriCode tool to obtain protocol software implementing the IETF WebSocket protocol. This demonstrates the scalability of our approach to real...... cause of test failures were mostly due to local and trivial errors in newly written code-generation templates, and not related to the overall logical operation of the protocol as specified by the CPN model....

  5. Using PRP and human amniotic fluid combination for osteogenesis in rabbit socket preservation

    Directory of Open Access Journals (Sweden)

    Amir Hossein Moradi

    2015-01-01

    Full Text Available Introduction: Platelet-rich plasma (PRP is used as an adjunct treatment during periodontal grafting surgery because of its capability of enhancing healing process. Amniotic fluid is a rich source of growth factors and hyaluronic acid (HA and a good point to study its properties of wound healing and bone formation. The aim of this study was to evaluate the osteogenic properties of a combination of amniotic fluid and PRP in rabbit′s dental socket preservation. Materials and Methods: The study population consisted of 24 healthy male laboratory rabbits (average weight 3,125 ± 185 gr that were randomly allocated into four groups. PRP for the first group, human amniotic fluid (HAF for the second group, a combination of PRP and HAF (PRHA for the third group was used. In the fourth (control group, no biomaterial was used. In each group, half of the rabbits were sacrificed at 4 weeks following surgery and the rest were sacrificed after 8 weeks. Histological analysis of biopsies of the sockets was performed using hematoxylin and eosin (H&E staining. Data were analyzed using Statistical Package for the Social Sciences (SPSS software (version 16 and P-value <0.05 was considered significance. Results: All three experimental groups showed positive effect on bone formation in terms of area of trabecular bone and number of osteocytes and also vessel formation. Socket preservation using HAF and PRHA showed the highest impact on bone formation. Socket preservation using HAF also had the highest impact on vessel formation. Conclusion: PRHA and HAF appear to be useful for enhancing bone formation. Since there was no difference between HAF and PRHA, it seems beneficial to use HAF due to its simplicity of application.

  6. Development and Evaluation of Secure Socket Layer Visualization Tool with Packet Capturing Function

    OpenAIRE

    Arai Masayuki

    2015-01-01

    Secure Socket Layer (SSL) has become a fundamental technology that secures browser-processed personal details sent to the server. As a result, communication and computer engineers are advised to learn the protocol. However, understanding SSL is very difficult because of its intricate communication procedure. To solve this problem, we developed a visualization tool for understanding SSL. This paper describes the design, implementation methods, and evaluation of the tool. The evaluation results...

  7. Effect of a ball skill intervention on children's ball skills and cognitive functions

    NARCIS (Netherlands)

    Westendorp-Haverdings, Marieke; Houwen, Suzanne; Hartman, Esther; Mombarg, Remo; Smith, Joanne; Visscher, Chris

    2014-01-01

    Purpose: This study examined the effect of a 16-wk ball skill intervention on the ball skills, executive functioning (in terms of problem solving and cognitive flexibility), and in how far improved executive functioning leads to improved reading and mathematics performance of children with learning

  8. Algorithm on robot soccer pass and shoot a ball

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Introduces of robot soccer's competition software of Harbin Institute of Technology(HIT), the con cept of running range and the method of calculating the running range for both the opponent and our teammates according to the distances Between the ball and robot soccers, and therefore the method of calculating the angle that the robot passes or shoots the ball according to the running ranges of both sides. And gives the examples of passing the ball when the ball's position is in the backcourt and shooting the ball when the ball's position is in the frontcourt.

  9. Ball Machine Usage in Tennis: Movement Initiation and Swing Timing While Returning Balls from a Ball Machine and from a Real Server

    Science.gov (United States)

    Carboch, Jan; Süss, Vladimir; Kocib, Tomas

    2014-01-01

    Practicing with the use of a ball machine could handicap a player compared to playing against an actual opponent. Recent studies have shown some differences in swing timing and movement coordination, when a player faces a ball projection machine as opposed to a human opponent. We focused on the time of movement initiation and on stroke timing during returning tennis serves (simulated by a ball machine or by a real server). Receivers’ movements were measured on a tennis court. In spite of using a serving ball speed from 90 kph to 135 kph, results showed significant differences in movement initiation and backswing duration between serves received from a ball machine and serves received from a real server. Players had shorter movement initiation when they faced a ball machine. Backswing duration was longer for the group using a ball machine. That demonstrates different movement timing of tennis returns when players face a ball machine. Use of ball machines in tennis practice should be limited as it may disrupt stroke timing. Key points Players have shorter initial move time when they are facing the ball machine. Using the ball machine results in different swing timing and movement coordination. The use of the ball machine should be limited. PMID:24790483

  10. Bone healing after low-level laser application in extraction sockets grafted with allograft material and covered with a resorbable collagen dressing: a pilot histological evaluation

    OpenAIRE

    Monea, Adriana; Beresescu, Gabriela; Tibor, Mezei; Popsor, Sorin; Antonescu, Dragos Mihai

    2015-01-01

    Background Our aim was to determine whether low level laser therapy (LLLT) can decrease the time between extraction/socket graft and implant placement, by evaluating histological changes in sockets grafted with a particulate allograft material and treated with LLLT. Methods Thirty patients had a socket grafted with a particulate allograft material (MinerOss) covered with a resorbable collagen wound dressing. The patients were then randomly divided into two equal groups (n = 15): test group re...

  11. HTML5 WebSocket protocol and its application to distributed computing

    OpenAIRE

    Muller, Gabriel L.

    2014-01-01

    HTML5 WebSocket protocol brings real time communication in web browsers to a new level. Daily, new products are designed to stay permanently connected to the web. WebSocket is the technology enabling this revolution. WebSockets are supported by all current browsers, but it is still a new technology in constant evolution. WebSockets are slowly replacing older client-server communication technologies. As opposed to comet-like technologies WebSockets' remarkable performances is a result of the p...

  12. Dry Socket following Tooth Extraction in an Iranian Dental Center: Incidence and Risk Factors Dry Socket following Tooth Extraction in an Iranian Dental Center: Incidence and Risk Factors

    Directory of Open Access Journals (Sweden)

    Majid Eshghpour

    2013-07-01

    Full Text Available Introduction: Dry Socket (DS is a common post-surgical complication following extraction of permanent teeth. Various risk factors has been mentioned for this complication including gender, age, amount of trauma during extraction, difficulty of extraction, inappropriate irrigation, infection, smoking, and oral contraceptive use. The aim of this study was to evaluate the incidence of DS among permanent teeth extraction in an Iranian Oral and Maxillofacial clinic and also to identify risk factors. Methods: This cross-sectional study performed at Mashhad Faculty of Dentistry between January 2009 and June 2009. Total of 785 patients who underwent non-surgical extraction of permanent teeth included in this study. A questionnaire with two sections designed to collect demographic, medical, and extraction-related data along with data regarding cases returning with DS. Data were reported descriptively and analyzed using Chi-square test with 95% confidence interval. Results: Total of 1073 teeth included in this study. 46.11% of patients were male and 53.89% were female. The mean age of participants was 32.68 ± 17.63 years. Total of 31 patients (2.89% were diagnosed with dry socket. Smoking and oral contraceptives intake had significant association with incidence of DS. In contrast, age, gender, medical status, tooth location, number of anesthetic carpules, anesthetic technique, pre-extraction antibiotic consumption, and academic year of students had no significant association with the incidence of DS. All cases with DS treated and were followed until resolution of DS. Conclusion: it is recommended to identify high risk groups (smokers and oral contraceptive takers when performing extraction and to perform preventive measures in these group of patients to attenuate postoperative complications.

  13. Mobile HTML5: Efficiency and Performance of WebSockets and Server-Sent Events

    OpenAIRE

    Estep, Eliot

    2013-01-01

    The advent of HTML5 (Hyper Text Markup Language revision 5) technologies are re-standardizing the web and paving the way for a new breed of real-time web applications. This has great potential for mobile browsers that are now supporting protocols such as WebSocket and Server-Sent Events (SSE). These protocols can provide ecient real-time communication in a scalable manner, especially for \\always-on" applications requiring persistent connections that are now widely used. Mobile devices are inh...

  14. Implementing a Remote Laboratory Experience into a Joint Engineering Degree Program: Aerodynamic Levitation of a Beach Ball

    Science.gov (United States)

    Jernigan, S. R.; Fahmy, Y.; Buckner, G. D.

    2009-01-01

    This paper details a successful and inexpensive implementation of a remote laboratory into a distance control systems course using readily available hardware and software. The physical experiment consists of a beach ball and a dc blower; the control objective is to make the height of the aerodynamically levitated beach ball track a reference…

  15. Calculation on Contact Stress and Optimization Design of Pitch Diameter of Ball Set for Rzeppa Universal Joint%球笼式万向节接触应力的计算及球组节圆直径的优化设计

    Institute of Scientific and Technical Information of China (English)

    石宝枢

    2011-01-01

    According to analysis on Hertz contact stress between two steel balls, the calculating equation of contact stress is deduced for steel balls, star - shaped sleeve and bell - shaped shell of rzeppa universal joint, and the optimal design of pitch diameter of ball set is carried out. The maximum contact stress is directly proportional to cube root of load is obtained, the optimized ball set pitch diameter coefficient K = 0.54 ~ O. 55.%根据2个钢球Hertz接触的应力分析,推导出球笼式万向节钢球与星形套和钟形壳接触的应力计算式,并对球组节圆直径进行了优化设计,得出钢球与星形套和钟形壳间的最大接触应力与载荷的立方根成正比,优化设计的球组节圆直径系数K=0.54~0.55.

  16. Reasonable Ball Size of Ball Mill for Preparing Coal Water Fuel and Forecasting Productive Capacity

    Institute of Scientific and Technical Information of China (English)

    张荣曾; 刘炯天; 徐志强; 郑明

    2002-01-01

    By using the matrix theory, a 5-parameter grinding mathema tical model is established. Based on the properties of feed coal and requirement s for size distribution of final product, the model gives the required grinding probability for various particles and corresponding ball size distribution. By u sing this model, 3 different sizes of ball mill are designed and put into commer cial use for coal water fuel. The forecasted ball mill capacity, the particle si zes and particle size distribution as well as the coal water fuel quality parame ters are all in line with industrial operation results, which have proved the su itability of the model.

  17. A three-dimensional finite element model of the transibial residual limb and prosthetic socket to predict skin temperatures.

    Science.gov (United States)

    Peery, Jeffrey T; Klute, Glenn K; Blevins, Joanna J; Ledoux, William R

    2006-09-01

    Amputees who wear prosthetic limbs often experience discomfort from blisters and sores due to mechanical insult; these skin conditions are exacerbated by elevated skin temperatures and excessive perspiration within the prosthetic socket. The goal of this study was to create a tool for developing new prostheses that accommodate varying thermal loads arising from everyday activities. A three-dimensional thermal model of a transtibial residual limb and prosthesis was constructed using the finite element (FE) method. Transverse computerized tomography (CT) scans were used to specify the geometry of the residual limb and socket. Thermal properties from the literature were assigned to both biological tissue and prosthetic socket elements. The purpose of this work was to create a model that would aid in testing the effect of new prosthesis designs on skin temperature. To validate its output, the model was used to predict the skin temperature distribution in a common prosthetic socket system (silicone liner, wool sock, and carbon fiber socket) at rest with no mechanical loading. Skin temperatures were generally elevated near muscle and decreased anteriorly and at the distal end. Experimental temperature measurements taken at the skin-prosthesis interface of five human subjects were used to validate the model. Data extracted from the thermal model at anterior, posterior, lateral, and medial locations were typically within one standard deviation of experimental results; the mean temperatures were within 0.3 degree C for each section and were within 0.1 degree C overall.

  18. Frictional torque numbers for ball cup and journal bearings

    NARCIS (Netherlands)

    Ligterink, D.J.

    1982-01-01

    Plastic bearing material wears in ball cup and journal bearings. Contact areas in the ball cup and the journal bearing increase. The frictional torque needed to rotate the ball or journal also increases. When the coefficient of friction is assumed to be constant during wearing out, the frictional t

  19. Frictional torque numbers for ball cup and journal bearings

    OpenAIRE

    Ligterink, D.J.

    1982-01-01

    Plastic bearing material wears in ball cup and journal bearings. Contact areas in the ball cup and the journal bearing increase. The frictional torque needed to rotate the ball or journal also increases. When the coefficient of friction is assumed to be constant during wearing out, the frictional torque increases to a maximum of 1.273 times the frictional torque at zero wear.

  20. Temperature and Coefficient of Restitution of a Table Tennis Ball

    Directory of Open Access Journals (Sweden)

    Yoonyoung Chang

    2016-01-01

    Full Text Available The coefficient of restitution (COR of a bouncing table tennis ball was measured at varying ball temperatures with a Motion Detector. It was found that there is a negative linear relationship between the COR and the temperature of the table tennis ball for temperatures ranging from 5 to 56 ̊C.

  1. The definitive guide to HTML5 WebSocket

    CERN Document Server

    Wang, Vanessa; Moskovits, Peter

    2013-01-01

    The Definitive Guide to HTML5 WebSocket is the ultimate insider's WebSocket resource. This revolutionary new web technology enables you to harness the power of true real-time connectivity and build responsive, modern web applications.   This book contains everything web developers and architects need to know about WebSocket. It discusses how WebSocket-based architectures provide a dramatic reduction in unnecessary network overhead and latency compared to older HTTP (Ajax) architectures, how to layer widely used protocols such as XMPP and STOMP on top of WebSocket, and how to secure WebSocket c

  2. Development and Evaluation of Secure Socket Layer Visualization Tool with Packet Capturing Function

    Directory of Open Access Journals (Sweden)

    Arai Masayuki

    2015-01-01

    Full Text Available Secure Socket Layer (SSL has become a fundamental technology that secures browser-processed personal details sent to the server. As a result, communication and computer engineers are advised to learn the protocol. However, understanding SSL is very difficult because of its intricate communication procedure. To solve this problem, we developed a visualization tool for understanding SSL. This paper describes the design, implementation methods, and evaluation of the tool. The evaluation results show that the visualization tool is effective for learning SSL.

  3. Integrated Voltage—Current Monitoring and Control of Gas Metal Arc Weld Magnetic Ball-Jointed Open Source 3-D Printer

    Directory of Open Access Journals (Sweden)

    Yuenyong Nilsiam

    2015-11-01

    Full Text Available To provide process optimization of metal fabricating self-replicating rapid prototyper (RepRap 3-D printers requires a low-cost sensor and data logger system to measure current (I and voltage (V of the gas metal arc welders (GMAW. This paper builds on previous open-source hardware development to provide a real-time measurement of welder I-V where the measuring circuit is connected to two analog inputs of the Arduino that is used to control the 3-D printer itself. Franklin firmware accessed through a web interface that is used to control the printer allows storing the measured values and downloading those stored readings to the user’s computer. To test this custom current and voltage monitoring device this study reports on its use on an upgraded all metal RepRap during the printing of aluminum alloy (ER1100, ER4043, ER4943, ER4047, and ER5356. The voltage and current data were analyzed on a per alloy basis and also layer-by-layer in order to evaluate the device’s efficacy as a monitoring device for 3-D printing and the results of the integrated design are discussed.

  4. Lawn tennis balls, Rolling friction experiment and Trouton viscosity

    CERN Document Server

    Singh, Ankit; Kulkarni, Kaustubh; Budhraja, Abhishek; Tej, K R Sai; Sankarlingam, Satish; Biswas, Anindya Kumar

    2008-01-01

    Three lawn tennis balls were arbitrarily taken. One ball was new, one was moderately old and another was old. We have fabricated a conveyor belt set-up and measured rolling friction coefficients, $\\mu_{r}$, of the three balls as a function of their angular velocities, $\\omega$. For the new ball, quadratic fit is perfect. For the moderately old ball, linear fit is accurate. In all the three cases, from linear fits, we obtain $k_{rol}$, where, $\\mu_{r}= k_{rol} \\omega + intercept$. We deduce $k_{rol}$ theoretically also, assuming Trouton ratio as three. The experimental results and theoretical estimates are of the same order of magnitude.

  5. Dust ball physics and the Schwarzschild metric

    CERN Document Server

    Kassner, Klaus

    2016-01-01

    A physics-first derivation of the Schwarzschild metric is given. Gravitation is described in terms of the effects of tidal forces (or of spacetime curvature) on the volume of a small ball of test particles (a dust ball), freely falling after all particles were at rest with respect to each other initially. The possibility to express Einstein's equation this way and some of its ramifications have been enjoyably discussed by Baez and Bunn [Am. J. Phys. 73, 644 (2005)]. Since the formulation avoids the use of tensors, neither advanced tensor calculus nor sophisticated differential geometry are needed in the calculation. The derivation is not lengthy and it has visual appeal, so it may be useful in teaching.

  6. Effect of Therapy Ball Seating on Learning and Sitting Discomforts among Saudi Female Students

    Directory of Open Access Journals (Sweden)

    Einas Al-Eisa

    2013-01-01

    Full Text Available The aim of the study was to evaluate the effect of therapy ball seating as an alternative for typical chair seating in a classroom. We evaluated the effect of ball seating on the student's sitting discomfort and academic performance using Cornell Musculoskeletal Discomfort Questionnaire and problem-based learning scales, respectively. A sample of convenience was taken. Data was collected and analyzed using t-test. Subjects experienced a major discomfort at neck and a minor discomfort at knee joint. Results showed that there was a significant improvement (P≤0.05 in sitting discomfort and student's performance when seated on therapy balls compared to typical classroom chairs. This study provides evidence for the effectiveness of therapy balls as a classroom seating for students who exhibit sitting discomfort and problem-based learning.

  7. A development methodology for a remote inspection system with JAVA and socket

    International Nuclear Information System (INIS)

    We have developed RISYS (Reactor Inspection System) which inspects reactor vessel welds by an underwater mobile robot. The system consists of a main control computer and an inspection robot which is controlled by the main control computer. Since the environments of the inspection tasks in a nuclear plant, like in other industrial fields, is very poor, serious accidents often happen. Therefore the necessity for remote inspection and control system has increased more and more. We have carried out the research for a remote inspection model for RISYS, and have adopted the world wide web, java, and socket technologies for it. Client interface to access the main control computer that controls the inspection equipment is essential for the development of a remote inspection system. It has been developed with a traditional programming language, for example, Visual C++, Visual Basic and X-Window. However, it is too expensive to vend and maintain the version of a interface program because of the different computer O/S. Nevertheless web and java technologies come to the fore to solve the problems but the java interpreting typed language could incur a performance problem in operating the remote inspection system. We suggest a methodology for developing a remote inspection system with java, a traditional programming language, and a socket programming that solves the java performance problem in this paper

  8. Independence, low balling and learning effects

    OpenAIRE

    Simons, Dirk

    2007-01-01

    Independent auditors serve as gatekeepers of public securities markets, but ongoing competition among audit firms could harm auditors’ independence. For instance, a Green Paper of the European Union finds that especially audits of large and prestigious clients are hard-fought in terms of price competition. Major concerns are related to a pricing behavior called low balling. Here, the auditor sets the first period’s fee below the audit costs -incurring a loss for the initial audit- in order to...

  9. Perceptual elements in Penn & Teller's "Cups and Balls" magic trick.

    Science.gov (United States)

    Rieiro, Hector; Martinez-Conde, Susana; Macknik, Stephen L

    2013-01-01

    Magic illusions provide the perceptual and cognitive scientist with a toolbox of experimental manipulations and testable hypotheses about the building blocks of conscious experience. Here we studied several sleight-of-hand manipulations in the performance of the classic "Cups and Balls" magic trick (where balls appear and disappear inside upside-down opaque cups). We examined a version inspired by the entertainment duo Penn & Teller, conducted with three opaque and subsequently with three transparent cups. Magician Teller used his right hand to load (i.e. introduce surreptitiously) a small ball inside each of two upside-down cups, one at a time, while using his left hand to remove a different ball from the upside-down bottom of the cup. The sleight at the third cup involved one of six manipulations: (a) standard maneuver, (b) standard maneuver without a third ball, (c) ball placed on the table, (d) ball lifted, (e) ball dropped to the floor, and (f) ball stuck to the cup. Seven subjects watched the videos of the performances while reporting, via button press, whenever balls were removed from the cups/table (button "1") or placed inside the cups/on the table (button "2"). Subjects' perception was more accurate with transparent than with opaque cups. Perceptual performance was worse for the conditions where the ball was placed on the table, or stuck to the cup, than for the standard maneuver. The condition in which the ball was lifted displaced the subjects' gaze position the most, whereas the condition in which there was no ball caused the smallest gaze displacement. Training improved the subjects' perceptual performance. Occlusion of the magician's face did not affect the subjects' perception, suggesting that gaze misdirection does not play a strong role in the Cups and Balls illusion. Our results have implications for how to optimize the performance of this classic magic trick, and for the types of hand and object motion that maximize magic misdirection.

  10. Simquake 3: Seismic interactions between building structures and rock-socketed foundations: Final report

    International Nuclear Information System (INIS)

    It has long been recognized that soil-structure interaction can significantly influence the earthquake response of massive structures such as nuclear power plant reactor buildings. The linear analysis methods that are widely used to model interaction phenomena can result in often unrecognized safety margins in design for earthquake excitation. Use of improved interaction models which capture nonlinear characteristics of interaction---such as energy dissipation and significant changes in stiffness---can provide realistic predictions of the earthquake loads imposed on nuclear power plant structures and equipment, supplying an improved basis for seismic design review. This report documents the results of a research effort investigating the soil-structure (or structure-media) interaction of reinforced concrete structures founded in backfilled rock sockets. The objectives of the research, which included field testing with semi-scale structural models, were: to examine the influence of the backfilled socket on structural dynamic response; and to develop an experimental data base for the benchmarking of computer simulation procedures

  11. Ball Machine Usage in Tennis: Movement Initiation and Swing Timing While Returning Balls from a Ball Machine and from a Real Server

    Directory of Open Access Journals (Sweden)

    Jan Carboch, Vladimir Süss, Tomas Kocib

    2014-06-01

    Full Text Available Practicing with the use of a ball machine could handicap a player compared to playing against an actual opponent. Recent studies have shown some differences in swing timing and movement coordination, when a player faces a ball projection machine as opposed to a human opponent. We focused on the time of movement initiation and on stroke timing during returning tennis serves (simulated by a ball machine or by a real server. Receivers’ movements were measured on a tennis court. In spite of using a serving ball speed from 90 kph to 135 kph, results showed significant differences in movement initiation and backswing duration between serves received from a ball machine and serves received from a real server. Players had shorter movement initiation when they faced a ball machine. Backswing duration was longer for the group using a ball machine. That demonstrates different movement timing of tennis returns when players face a ball machine. Use of ball machines in tennis practice should be limited as it may disrupt stroke timing.

  12. Effects of caffeic acid phenethyl ester on palatal mucosal defects and tooth extraction sockets

    Directory of Open Access Journals (Sweden)

    Günay A

    2014-10-01

    Full Text Available Ahmet Günay,1 Osman Fatih Arpağ,2 Serhat Atilgan,3 Ferhan Yaman,3 Yusuf Atalay,4 İzzet Acikan3 1Department of Periodontology, Faculty of Dentistry, Dicle University, Diyarbakir, Turkey; 2Department of Periodontology, Faculty of Dentistry, Mustafa Kemal University, Hatay, Turkey; 3Department of Maxillofacial Surgery, Faculty of Dentistry, Dicle University, Diyarbakir, Turkey; 4Department of Maxillofacial Surgery, Faculty of Dentistry, Kocatepe University, Afyon, Turkey Aim: The purpose of this study was to evaluate the effects of caffeic acid phenethyl ester (CAPE on palatal mucosal defects and tooth extraction sockets in an experimental model.Materials and methods: Forty-two male Sprague-Dawley rats with a mean age of 7 weeks and weighing 280–490 g were used in this study. The rats were randomly divided into two groups: group A (the control group, n=21 and group B (the experimental group, n=21. Under anesthesia with ketamine (8 mg/100 g, intraperitoneally, palatal mucosal defects were created and tooth extraction was performed in the rats in groups A and B. Group A received no treatment, whereas group B received CAPE. CAPE was injected daily (10 µmol/kg, intraperitoneally. The rats were killed on days 7, 14, and 30 after the procedures. Palatal mucosa healing and changes in bone tissue and fibrous tissue were evaluated histopathologically.Result: Pairwise comparisons showed no statistically significant difference between days 7 and 14 in either group (P>0.05. At day 30, bone healing was significantly better in group B (CAPE than in group A (control (P<0.05. Fibrinogen levels at day 30 were significantly higher in group A (control than in group B (CAPE (P<0.05. Pairwise comparisons showed no statistically significant difference in palatal mucosa healing levels between days 7 and 14 in both groups (P>0.05.Conclusion: In conclusion, the findings of this study suggest that CAPE can significantly improve tooth socket healing. Keywords: caffeic

  13. Walk and roll robot

    Science.gov (United States)

    Wilson, Andrew (Inventor); Punnoose, Andrew (Inventor); Strausser, Katherine (Inventor); Parikh, Neil (Inventor)

    2011-01-01

    A mobile robotic unit features a main body, a plurality of legs for supporting the main body on and moving the main body in forward and reverse directions about a base surface, and a drive assembly. According to an exemplary embodiment each leg includes a respective pivotal hip joint, a pivotal knee joint, and a wheeled foot adapted to roll along the base surface. Also according to an exemplary embodiments the drive assembly includes a motor operatively associated with the hip and knee joints and the wheeled foot for independently driving pivotal movement of the hip joint and the knee joint and rolling motion of the wheeled foot. The hip joint may include a ball-and-socket-type joint interconnecting top portion of the leg to the main body, such that the hip joint is adapted to pivot said leg in a direction transverse to a forward-and-reverse direction.

  14. Bouncing Balls and Graphing Derivatives

    Science.gov (United States)

    Cory, Beth

    2010-01-01

    National Council of Teachers of Mathematics' (NCTM's) (2000) Connections Standard states that students should "recognize and use connections among mathematical ideas; understand how mathematical ideas interconnect ...; [and] recognize and apply mathematics in contexts outside of mathematics" (p. 354). This article presents an in-depth…

  15. LOW COMPRESSION TENNIS BALLS AND SKILL DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    John Hammond

    2006-12-01

    Full Text Available Coaching aims to improve player performance and coaches have a number of coaching methods and strategies they use to enhance this process. If new methods and ideas can be determined to improve player performance they will change coaching practices and processes. This study investigated the effects of using low compression balls (LCBs during coaching sessions with beginning tennis players. In order to assess the effectiveness of LCBs on skill learning the study employed a quasi-experimental design supported by qualitative and descriptive data. Beginner tennis players took part in coaching sessions, one group using the LCBs while the other group used standard tennis balls. Both groups were administered a skills at the beginning of a series of coaching sessions and again at the end. A statistical investigation of the difference between pre and post-test results was carried out to determine the effect of LCBs on skill learning. Additional qualitative data was obtained through interviews, video capture and the use of performance analysis of typical coaching sessions for each group. The skill test results indicated no difference in skill learning when comparing beginners using the LCBs to those using the standard balls. Coaches reported that the LCBs appeared to have a positive effect on technique development, including aspects of technique that are related to improving power of the shot. Additional benefits were that rallies went on longer and more opportunity for positive reinforcement. In order to provide a more conclusive answer to the effects of LCBs on skill learning and technique development recommendations for future research were established including a more controlled experimental environment and larger sample sizes across a longer period of time

  16. Portable Library of Migratable Sockets

    Directory of Open Access Journals (Sweden)

    Marian Bubak

    2001-01-01

    Full Text Available Efficient load balancing is essential for parallel distributed computing. Many parallel computing environments use TCP or UDP through the socket interface as a communication mechanism. This paper presents the design and development of a prototype implementation of a network interface that can preserve communication between processes during process migration. This new communication library is a substitution for the well-known socket interface. It is implemented in user — space; it is portable, and no modifications of user applications are required. TCP/IP is applied for internal communication, which guarantees relatively high performance and portability.

  17. Socket preservation using demineralized freezed dried bone allograft with and without plasma rich in growth factor: A canine study

    Directory of Open Access Journals (Sweden)

    Ahmad Mogharehabed

    2014-01-01

    Full Text Available Background: The accelerating effect of plasma rich in growth factors (PRGFs in the healing of extraction sockets has been demonstrated by some studies. The aim of the present study was to histologically and histomorphometrically evaluate whether bone formation would increase by the combined use of PRGF and demineralized freeze-dried bone allograft (DFDBA. Materials and Methods: In four female dogs, the distal root of the second, third and fourth lower premolars were extracted bilaterally and the mesial roots were preserved. The extraction sockets were randomly divided into DFDBA + PRGF, DFDBA + saline or control groups. Two dogs were sacrificed after 2 weeks and two dogs were sacrificed after 6 weeks. The extraction sockets were evaluated from both histological and histomorphometrical aspects. The data were analyzed by Mann-Whitney followed by Kruskal-Wallis tests using the Statistical Package for the Social Sciences version 20 (SPSS Inc., Chicago, IL, USA. Significant levels were set at 0.05. Results: The least decrease in socket height was observed in the DFDBA + PRGF group (0.73 ± 0.42 mm. The least decrease in the coronal portion was observed in the DFDBA + PRGF group (1.38 ± 1.35 mm². The least decrease in the middle surface was observed in the DFDBA group (0.61 ± 0.80 mm². The least decrease in the apical portion was observed in the DFDBA group (0.34 ± 0.39 mm². Conclusion: The present study showed better socket preservation subsequent to the application of DFDBA and PRGF combination in comparison with the two other groups. However, the difference was not statistically significant.

  18. A novel prosthetic device and method for guided tissue preservation of immediate postextraction socket implants.

    Science.gov (United States)

    Chu, Stephen J; Hochman, Mark N; Tan-Chu, Jocelyn Hui-Ping; Mieleszko, Adam J; Tarnow, Dennis P

    2014-01-01

    Preservation of the surrounding hard and soft tissues associated with an immediate postextraction socket implant to replace a nonrestorable tooth in the esthetic zone is one of the greatest challenges facing the dental team. Several studies have documented the biologic and esthetic benefits of bone graft containment with either a custom healing abutment or provisional restoration. Use of a prefabricated shell that replicates the extracted tooth at the cervical region can help achieve guided tissue preservation and sustainable esthetic outcomes in an easy, simple, consistent, and less time consuming way. The following case report of a hopeless maxillary right central incisor in a female patient possessing adjacent teeth with a thin periodontal phenotype illustrates this new treatment device, method, and concept.

  19. Accuracy and Reliability of a New Tennis Ball Machine

    OpenAIRE

    Cyril Brechbuhl, Grégoire Millet, Laurent Schmitt

    2016-01-01

    The aim was to evaluate the reliability of a newly-developed ball machine named 'Hightof', on the field and to assess its accuracy. The experiment was conducted in the collaboration of the 'Hawk-Eye' technology. The accuracy and reliability of this ball machine were assessed during an incremental test, with 1 min of exercise and 30 sec of recovery, where the frequency of the balls increased from 10 to 30 balls·min-1. The initial frequency was 10 and increased by 2 until 22, then by 1 until 30...

  20. Graphene oxide scaffold accelerates cellular proliferative response and alveolar bone healing of tooth extraction socket.

    Science.gov (United States)

    Nishida, Erika; Miyaji, Hirofumi; Kato, Akihito; Takita, Hiroko; Iwanaga, Toshihiko; Momose, Takehito; Ogawa, Kosuke; Murakami, Shusuke; Sugaya, Tsutomu; Kawanami, Masamitsu

    2016-01-01

    Graphene oxide (GO) consisting of a carbon monolayer has been widely investigated for tissue engineering platforms because of its unique properties. For this study, we fabricated a GO-applied scaffold and assessed the cellular and tissue behaviors in the scaffold. A preclinical test was conducted to ascertain whether the GO scaffold promoted bone induction in dog tooth extraction sockets. For this study, GO scaffolds were prepared by coating the surface of a collagen sponge scaffold with 0.1 and 1 µg/mL GO dispersion. Scaffolds were characterized using scanning electron microscopy (SEM), physical testing, cell seeding, and rat subcutaneous implant testing. Then a GO scaffold was implanted into a dog tooth extraction socket. Histological observations were made at 2 weeks postsurgery. SEM observations show that GO attached to the surface of collagen scaffold struts. The GO scaffold exhibited an interconnected structure resembling that of control subjects. GO application improved the physical strength, enzyme resistance, and adsorption of calcium and proteins. Cytocompatibility tests showed that GO application significantly increased osteoblastic MC3T3-E1 cell proliferation. In addition, an assessment of rat subcutaneous tissue response revealed that implantation of 1 µg/mL GO scaffold stimulated cellular ingrowth behavior, suggesting that the GO scaffold exhibited good biocompatibility. The tissue ingrowth area and DNA contents of 1 µg/mL GO scaffold were, respectively, approximately 2.5-fold and 1.4-fold greater than those of the control. Particularly, the infiltration of ED2-positive (M2) macrophages and blood vessels were prominent in the GO scaffold. Dog bone-formation tests showed that 1 µg/mL GO scaffold implantation enhanced bone formation. New bone formation following GO scaffold implantation was enhanced fivefold compared to that in control subjects. These results suggest that GO was biocompatible and had high bone-formation capability for the scaffold

  1. Interpolating sliding mode observer for a ball and beam system

    Science.gov (United States)

    Luai Hammadih, Mohammad; Hosani, Khalifa Al; Boiko, Igor

    2016-09-01

    A principle of interpolating sliding mode observer is introduced in this paper. The observer incorporates multiple linear observers through interpolation of multiple estimates, which is treated as a type of adaptation. The principle is then applied to the ball and beam system for observation of the slope of the beam from the measurement of the ball position. The linearised model of the ball and beam system using multiple linearisation points is developed. The observer dynamics implemented in Matlab/Simulink Real Time Workshop environment. Experiments conducted on the ball and beam experimental setup demonstrate excellent performance of the designed novel interpolating (adaptive) observer.

  2. Fourier-Laguerre transform, convolution and wavelets on the ball

    CERN Document Server

    McEwen, J D

    2013-01-01

    We review the Fourier-Laguerre transform, an alternative harmonic analysis on the three-dimensional ball to the usual Fourier-Bessel transform. The Fourier-Laguerre transform exhibits an exact quadrature rule and thus leads to a sampling theorem on the ball. We study the definition of convolution on the ball in this context, showing explicitly how translation on the radial line may be viewed as convolution with a shifted Dirac delta function. We review the exact Fourier-Laguerre wavelet transform on the ball, coined flaglets, and show that flaglets constitute a tight frame.

  3. Wear numbers for ball cup and journal bearings

    NARCIS (Netherlands)

    Ligterink, D.J.; Moes, H.

    1980-01-01

    A wear number is defined for ball cup bearings and for journal bearings where the cup and the cylindrical bearing are made of soft material. This dimensionless wear number provides a relation between the following five quantities: the radius of the ball or the length of the journal bearing in millim

  4. Exact solutions, energy, and charge of stable Q-balls

    Energy Technology Data Exchange (ETDEWEB)

    Bazeia, D.; Marques, M.A. [Universidade Federal da Paraiba, Departamento de Fisica, Joao Pessoa, PB (Brazil); Menezes, R. [Universidade Federal da Paraiba, Departamento de Ciencias Exatas, Rio Tinto, PB (Brazil); Universidade Federal de Campina Grande, Departamento de Fisica, Campina Grande, PB (Brazil)

    2016-05-15

    In this work we deal with nontopological solutions of the Q-ball type in two spacetime dimensions. We study models of current interest, described by a Higgs-like and other, similar potentials which unveil the presence of exact solutions. We use the analytic results to investigate how to control the energy and charge to make the Q-balls stable. (orig.)

  5. Video movie making using remote procedure calls and 4BSD Unix sockets on Unix, UNICOS, and MS-DOS systems

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, D.W.; Johnston, W.E.; Hall, D.E.; Rosenblum, M.

    1990-03-01

    We describe the use of the Sun Remote Procedure Call and Unix socket interprocess communication mechanisms to provide the network transport for a distributed, client-server based, image handling system. Clients run under Unix or UNICOS and servers run under Unix or MS-DOS. The use of remote procedure calls across local or wide-area networks to make video movies is addressed.

  6. Cohesion in ball lightning and cook plasmas

    International Nuclear Information System (INIS)

    The phenomenon of ball lightning has been observed for a long time, but the nature of these luminous balls has been unknown. It is proposed here that they consist of highly excited Rydberg atoms with large polarizabilities. Thus the cohesion of the balls comes from photon exchange forces (London dispersion forces) rather than electron exchange (chemical) forces. The cohesion in plasmas generated at the back faces of detonating explosives (Cook's plasmas) may have a similar basis. Numerical estimates are given to justify these interpretations

  7. Accuracy and Reliability of a New Tennis Ball Machine

    Directory of Open Access Journals (Sweden)

    Cyril Brechbuhl, Grégoire Millet, Laurent Schmitt

    2016-06-01

    Full Text Available The aim was to evaluate the reliability of a newly-developed ball machine named 'Hightof', on the field and to assess its accuracy. The experiment was conducted in the collaboration of the 'Hawk-Eye' technology. The accuracy and reliability of this ball machine were assessed during an incremental test, with 1 min of exercise and 30 sec of recovery, where the frequency of the balls increased from 10 to 30 balls·min-1. The initial frequency was 10 and increased by 2 until 22, then by 1 until 30 balls·min-1. The reference points for the impact were 8.39m from the net and 2.70m from lateral line for the right side and 2.83m for the left side. The precision of the machine was similar on the right and left sides (0.63 ± 0.39 vs 0.63 ± 0.34 m. The distances to the reference point were 0.52 ± 0.42, 0.26 ± 0.19, 0.52 ± 0.37, 0.28 ± 0.19 m for the Y-right, X-right, Y-left and X-left impacts. The precision was constant and did not increase with the intensity. (e.g ball frequency. The ball velocity was 86.3 ± 1.5 and 86.5 ± 1.3 km·h-1 for the right and the left side, respectively. The coefficient of variation for the velocity ranged between 1 and 2% in all stages (ball velocity ranging from 10 to 30 balls·min-1. Conclusion: both the accuracy and the reliability of this new ball machine appear satisfying enough for field testing and training.

  8. Acute neuropathic joint in diabetic foot: Plain radiographic findings

    International Nuclear Information System (INIS)

    To determine the plain film findings of acute neuropathic joint in diabetic foot. Acute neuropathic joint in diabetic foot was considered when fragmentation of the articular ends of bone and subluxation of the affected joint developed within eight weeks after clinical onset of diabetic gangrene. Eight toes of six diabetics were satisfactory to our criteria. We analyzed plain radiographic findings of the affected joint and soft tissue, interval changes in followed-up radiographs, and deformities after healing. The time interval between clinical onset of gangrene and bone destruction ranges from 2 weeks to 4 weeks(mean 2.6 weeks). Plane radiographs showed fragmentation of the articular ends, subluxation, and soft tissue swelling of the metatarsophalangeal joint or interphalangeal joint. The significant feature of these patients was rapid progression of the lesions. Clinically, all patients had diabetic gangrene in affected toes, however, there was no evidence of osteomyelitis in our series. Amputation was done in 2 cases, and lesions in 3 of the remaining 4 cases were repaired spontaneously with regression of gangrene, leaving radiological residua such as pointed-end, tapered-end, and ball and socket deformity. Rapid disorganisation of the joint with associated evidence of soft tissue gangrene in plain radiograph is believed to be valuable for the diagnosis of diabetic osteoarthropathy

  9. Acute neuropathic joint in diabetic foot: Plain radiographic findings

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Dae Young; Kang, Heung Sik; Sim, Jung Suk; Yoon, Yong Kyu; Kim, Chu Wan [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1994-05-15

    To determine the plain film findings of acute neuropathic joint in diabetic foot. Acute neuropathic joint in diabetic foot was considered when fragmentation of the articular ends of bone and subluxation of the affected joint developed within eight weeks after clinical onset of diabetic gangrene. Eight toes of six diabetics were satisfactory to our criteria. We analyzed plain radiographic findings of the affected joint and soft tissue, interval changes in followed-up radiographs, and deformities after healing. The time interval between clinical onset of gangrene and bone destruction ranges from 2 weeks to 4 weeks(mean 2.6 weeks). Plane radiographs showed fragmentation of the articular ends, subluxation, and soft tissue swelling of the metatarsophalangeal joint or interphalangeal joint. The significant feature of these patients was rapid progression of the lesions. Clinically, all patients had diabetic gangrene in affected toes, however, there was no evidence of osteomyelitis in our series. Amputation was done in 2 cases, and lesions in 3 of the remaining 4 cases were repaired spontaneously with regression of gangrene, leaving radiological residua such as pointed-end, tapered-end, and ball and socket deformity. Rapid disorganisation of the joint with associated evidence of soft tissue gangrene in plain radiograph is believed to be valuable for the diagnosis of diabetic osteoarthropathy.

  10. Graphene oxide scaffold accelerates cellular proliferative response and alveolar bone healing of tooth extraction socket

    Directory of Open Access Journals (Sweden)

    Nishida E

    2016-05-01

    Full Text Available Erika Nishida,1 Hirofumi Miyaji,1 Akihito Kato,1 Hiroko Takita,2 Toshihiko Iwanaga,3 Takehito Momose,1 Kosuke Ogawa,1 Shusuke Murakami,1 Tsutomu Sugaya,1 Masamitsu Kawanami11Department of Periodontology and Endodontology, Hokkaido University Graduate School of Dental Medicine, Sapporo, Japan; 2Support Section for Education and Research, Hokkaido University Graduate School of Dental Medicine, Sapporo, Japan; 3Laboratory of Histology and Cytology, Hokkaido University Graduate School of Medicine, Sapporo, JapanAbstract: Graphene oxide (GO consisting of a carbon monolayer has been widely investigated for tissue engineering platforms because of its unique properties. For this study, we fabricated a GO-applied scaffold and assessed the cellular and tissue behaviors in the scaffold. A preclinical test was conducted to ascertain whether the GO scaffold promoted bone induction in dog tooth extraction sockets. For this study, GO scaffolds were prepared by coating the surface of a collagen sponge scaffold with 0.1 and 1 µg/mL GO dispersion. Scaffolds were characterized using scanning electron microscopy (SEM, physical testing, cell seeding, and rat subcutaneous implant testing. Then a GO scaffold was implanted into a dog tooth extraction socket. Histological observations were made at 2 weeks postsurgery. SEM observations show that GO attached to the surface of collagen scaffold struts. The GO scaffold exhibited an interconnected structure resembling that of control subjects. GO application improved the physical strength, enzyme resistance, and adsorption of calcium and proteins. Cytocompatibility tests showed that GO application significantly increased osteoblastic MC3T3-E1 cell proliferation. In addition, an assessment of rat subcutaneous tissue response revealed that implantation of 1 µg/mL GO scaffold stimulated cellular ingrowth behavior, suggesting that the GO scaffold exhibited good biocompatibility. The tissue ingrowth area and DNA contents of 1

  11. Structure and magnetism of SmCo5 nanoflakes prepared by surfactant-assisted ball milling with different ball sizes

    International Nuclear Information System (INIS)

    Anisotropic magnetic SmCo5 nanoflakes have been fabricated by surfactant-assisted ball milling (SABM) using hardened steel balls of one of the following sizes: 4, 6.5, 9.5 and 12.7 mm in diameters. The magnetic properties of SmCo5 particles prepared by SABM with different milling ball sizes in diameters were investigated systematically. It was showed that the nanoflakes milled by amount of small size balls had a higher coercivity and lower anisotropy, i.e., worse grain orientation although in a short milling time while the nanoflakes prepared with same weight of big balls tend to have a lower coercivity, better grain orientation. The coercivity mechanism of the nanoflake was studied and it was mainly dominated with the domain-wall pinning. The SEM analysis shows that the morphology of nanoflakes prepared with different ball sizes are almost the same when the balls to powder weight ratio is fixed. The different magnetic properties caused by different ball sizes are mainly due to the different microstructure changes, i.e, grain refinement and c-axis orientation, which are demonstrated by X-ray diffraction (XRD) analysis and transmission electron microscope (TEM). Based on the experiments above, a combined milling process was suggested and done to improve magnetic properties as your need. - Highlights: • We fabricated anisotropic magnetic SmCo5 nanoflakes by surfactant-assisted ball milling (SABM). • We investigated the magnetic properties of SmCo5 particles systematically. It was showed that the coercivity, high or low, and grain orientation, good or bad, were influenced strongly by balls size. The different magnetisms caused by different ball sizes is mainly due to the different microstructure changes. • The coercivity mechanism of the nanoflake was studied and it was mainly dominated with the domain-wall pinning

  12. Design and Control of an Active Electrical Knee and Ankle Prosthesis

    OpenAIRE

    Sup, Frank; Varol, Huseyin Atakan; Mitchell, Jason; Withrow, Thomas; Goldfarb, Michael

    2008-01-01

    This paper presents an overview of the design and control of an electrically powered knee and ankle prosthesis. The prosthesis design incorporates two motor-driven ball screw units to drive the knee and ankle joints. A spring in parallel with the ankle motor unit is employed to decrease the power consumption and increase the torque output for a given motor size. The device’s sensor package includes a custom load cell to measure the sagittal socket interface moment above the knee joint, a cust...

  13. A New Hybrid Network Sniffer Model Based on Pcap Language and Sockets (Pcapsocks

    Directory of Open Access Journals (Sweden)

    Azidine GUEZZAZ

    2016-02-01

    Full Text Available Nowadays, the protection and the security of data transited within computer networks represent a real challenge for developers of computer applications and network administrators. The Intrusion Detection System and Intrusion Prevention System are the reliable techniques for a Good security. Any detected intrusion is based on data collection. So, the collection of an important and significant traffic on the monitored systems is an interesting feature. Thus, the first task of Intrusion Detection System and Intrusion Prevention System is to collect information’s basis to treat and analyze them, and to make accurate decisions. Network analysis can be used to improve networks performances and their security, but it can also be used for malicious tasks. Our main goal in this article is to design a reliable and powerful network sniffer, called PcapSockS, based on pcap language and sockets, able to intercept traffic in three modes: connected, connectionless and raw mode. We start with the performances assessment performed on a list of most expanded and most recently used network sniffers. The study will be completed by a classification of these sniffers related to computer security objectives based on parameters library (libpcap/winpcap or libnet, filtering, availability, software or hardware, alert and real time. The PcapSockS provides a nice performance integrating reliable sniffing mechanisms that allow a supervision taking into account some low and high-level protocols for TCP and UDP network communications.

  14. Science of Ball Lightning (Fire Ball)

    Science.gov (United States)

    Ohtsuki, Yoshi-Hiko

    1989-08-01

    The Table of Contents for the full book PDF is as follows: * Organizing Committee * Preface * Ball Lightning -- The Continuing Challenge * Hungarian Ball Lightning Observations in 1987 * Nature of Ball Lightning in Japan * Phenomenological and Psychological Analysis of 150 Austrian Ball Lightning Reports * Physical Problems and Physical Properties of Ball Lightning * Statistical Analysis of the Ball Lightning Properties * A Fluid-Dynamical Model for Ball Lightning and Bead Lightning * The Lifetime of Hill's Vortex * Electrical and Radiative Properties of Ball Lightning * The Candle Flame as a Model of Ball Lightning * A Model for Ball Lightning * The High-Temperature Physico-Chemical Processes in the Lightning Storm Atmosphere (A Physico-Chemical Model of Ball Lightning) * New Approach to Ball Lightning * A Calculation of Electric Field of Ball Lightning * The Physical Explanation to the UFO over Xinjiang, Northern West China * Electric Reconnection, Critical Ionization Velocity, Ponderomotive Force, and Their Applications to Triggered and Ball Lightning * The PLASMAK™ Configuration and Ball Lightning * Experimental Research on Ball Lightning * Performance of High-Voltage Test Facility Designed for Investigation of Ball Lightning * List of Participants

  15. Holy balls!

    OpenAIRE

    Wright, Michael; Langley, Ken; Belden, Jesse; Truscott, Tadd

    2011-01-01

    We demonstrate the behavior of three balls skipping off of the water surface: a Superball, a racquetball, and a water bouncing ball (Waboba). The three balls have rebound coefficients of 0.9, 0.8 and 0.2, respectively. However, we notice that the Waboba bounces better than the others, but why? The Superball has a high coefficient of restitution, creating large rebounds. Here the impact is angled to the free surface, but the inelastic response and large mass ratio forces the ball underwater wi...

  16. Transport in rotary drums and ball mills

    International Nuclear Information System (INIS)

    This report contains investigations into the influence exerted by operating conditions, material properties and geometry of the apparatus and of the discharge plate on the transport behaviour of narrow quartz sand fractions in a model apparatus. The transport coefficients are determined in residence time experiments with Na-24-labelling. The dependence obtained between the transport coefficients and the experimental parameters permits a coherent interpretation if the assumption is made that the two types of transport occur in different phases of radial motion: Convection takes place during ascend while axial dispersion is generated in the falling and ranging process. Furthermore, a model has been developed for evaluating the throughput of rotary drums and ball mills, respectively; it is based on the assumption that the throughput is governed by the material flux through the discharge plate. The efflux takes place only in the ascending zone as a result of gravity and centrifugal forces acting parallel to the discharge plate. A deduced relationship describing the material flow through the discharge apertures in connection with the calculable zone of ascend leads to an expression allowing to determine the mass flow rate as a function of material properties, operating conditions and geometry of the discharge plate. A comparison between experimental and calculated data shows good agreement. (orig.)

  17. Implementing the WebSocket Protocol Based on Formal Modelling and Automated Code Generation

    DEFF Research Database (Denmark)

    Simonsen, Kent Inge; Kristensen, Lars Michael

    2014-01-01

    with pragmatic annotations for automated code generation of protocol software. The contribution of this paper is an application of the approach as implemented in the PetriCode tool to obtain protocol software implementing the IETF WebSocket protocol. This demonstrates the scalability of our approach to real...

  18. Dynamic interface pressure distributions of two transtibial prosthetic socket concepts.

    Science.gov (United States)

    Dumbleton, Tim; Buis, Arjan W P; McFadyen, Angus; McHugh, Brendan F; McKay, Geoff; Murray, Kevin D; Sexton, Sandra

    2009-01-01

    In this study, we investigated and compared the dynamic interface pressure distribution of hands-off and hands-on transtibial prosthetic systems by means of pressure mapping. Of the 48 established unilateral amputees recruited, half (n = 24) had been wearing pressure-cast prostheses (IceCast Compact) and the other half (n = 24) had been wearing hand-cast sockets of the patellar tendon bearing design. We measured the dynamic pressure profile of more than 90% of the area within each prosthetic socket by means of four Tekscan F-Scan socket transducer arrays. We compared the interface pressure between socket concepts. We found that the distribution of dynamic pressure at the limb-socket interface was similar for the two intervention (socket prescription) groups. However, a significant difference was found in the magnitude of the interface pressure between the two socket concepts; the interface pressures recorded in the hands-off sockets were higher than those seen in the hands-on concept. Despite the differences in interface pressure, the level of satisfaction with the sockets was similar between subject groups. The sockets instrumented for this study had been in daily use for at least 6 months, with no residual-limb health problems.

  19. Security Testing of WebSockets

    OpenAIRE

    Kuosmanen, Harri

    2016-01-01

    The current state of WebSocket is not an exception when it comes to security issues in traditional web applications. There are vulnerabilities that commonly exist in WebSocket implementations that any attacker could potentially exploit. In order to build a protection to avoid these vulnerabilities it needs to be understood what the vulnerabilities are and how they are discovered, how can they be exploited, and how can they be defended against. Many of the commonly known web applicatio...

  20. An overview of Ball Aerospace cryogen storage and delivery systems

    Science.gov (United States)

    Marquardt, J.; Keller, J.; Mills, G.; Schmidt, J.

    2015-12-01

    Starting on the Gemini program in the 1960s, Beech Aircraft (now Ball Aerospace) has been designing and manufacturing dewars for a variety of cryogens including liquid hydrogen and oxygen. These dewars flew on the Apollo, Skylab and Space Shuttle spacecraft providing fuel cell reactants resulting in over 150 manned spaceflights. Since Space Shuttle, Ball has also built the liquid hydrogen fuel tanks for the Boeing Phantom Eye unmanned aerial vehicle. Returning back to its fuel cell days, Ball has designed, built and tested a volume-constrained liquid hydrogen and oxygen tank system for reactant delivery to fuel cells on unmanned undersea vehicles (UUVs). Herein past history of Ball technology is described. Testing has been completed on the UUV specific design, which will be described.

  1. Exercise recommendations after total joint replacement: a review of the current literature and proposal of scientifically based guidelines.

    Science.gov (United States)

    Kuster, Markus S

    2002-01-01

    ball and socket joint, the flexion angle does not play an important role. During activities such as hiking or jogging, high joint loads occur between 40 and 60 degrees of knee flexion where many knee designs are not conforming and high polyethylene inlay stress will occur. Regular jogging or hiking produces high inlay stress with the danger of delamination and polyethylene destruction for most current total knee prostheses. Based on these design differences between hip and knee replacements it is prudent to be more conservative after total knee arthroplasty than after total hip arthroplasty for activities that exhibit high joint loads in knee flexion. PMID:12015805

  2. Neutrino Balls and Gamma-Ray Bursts

    CERN Document Server

    Holdom, B

    1994-01-01

    We propose a mechanism by which the neutrino emission from a supernova-type explosion can be converted into a gamma-ray burst of total energy $\\sim 10^{50}$ ergs. This occurs naturally if the explosion is situated inside a ball of trapped neutrinos, which in turn may lie at a galactic core. There are possible unique signatures of this scenario.

  3. Wear numbers for ball cup and journal bearings

    OpenAIRE

    Ligterink, D.J.; Moes, H.

    1980-01-01

    A wear number is defined for ball cup bearings and for journal bearings where the cup and the cylindrical bearing are made of soft material. This dimensionless wear number provides a relation between the following five quantities: the radius of the ball or the length of the journal bearing in millimetres, the wear modulus in newtons per square millimetre, the maximum wear depth rate of the cup or the cylindrical bearing in millimetres per second, the force between the mating surfaces in newto...

  4. Effects of platelet-rich plasma on healing of alveolar socket: Split-mouth histological and histometric evaluation in Cebus apella monkeys

    Directory of Open Access Journals (Sweden)

    Pessoa Roberto

    2009-01-01

    Full Text Available Context: The prediction of implant treatment is directly influenced by the quality of the remaining bone after tooth extraction. Aims : The purpose of this experimental study was to, histologically and histometrically, evaluate the bone repair process in the central areas of extraction sockets filled with platelet-rich plasma. Materials and Methods: Four young adult male Cebus apella monkeys were used. The extraction of both right and left inferior second premolars was accomplished. After extraction, in one of the extraction sockets, coagulum was maintained while in the other it was removed; the alveolus was dried with gauze compress and filled up with platelet concentrate. For PRP production, Sonnleitner′s protocol was followed. The specimens for histological and histometric assessment were obtained in 30, 90, 120 and 180 days intervals. Results: In 30 days new bone formation was intense in both experimental and control sockets and no significant differences were observed between the two groups. After 90 days of the extraction, while the control group showed signs of decrease in osteogenesis, in the experimental unit, the process of bone formation and fibroblast-like cell proliferation remained intense. After 120 days, the PRP treated socket was occupied by large trabeculae of bone. After 180 days, the control unit was occupied mostly with bone marrow. The experimental unit remained occupied with large amounts of bone tissue. Conclusions: It was possible to conclude that bone repair was enhanced by the use of platelet- rich plasma in alveolar sockets.

  5. Design of a novel prosthetic socket: assessment of the thermal performance.

    Science.gov (United States)

    Webber, Christina M; Davis, Brian L

    2015-05-01

    Prosthetic liners and sockets insulate the residual limb, causing excessive sweating and concomitant skin maceration. When coupled with atypical loading conditions, further dermatologic problems can arise. This can significantly reduce the quality of life of an amputee patient. Improving the design of the prosthetic socket has been proposed as a means of reestablishing a normal thermal environment around the residual limb. In this study, a prosthetic socket was modified by incorporating a helical cooling channel within the socket wall using additive manufacturing techniques. Two sockets were modeled: a control socket, and a modified socket containing a 0.48 cm diameter cooling channel. Computer simulations and bench-top testing were used to assess the design's ability to create a greater temperature differential across the socket wall. A greater temperature drop across the socket wall suggested that the socket could provide cooling benefits to the residual limb by allowing for heat to be drawn away from the limb. The temperature difference across the socket wall was calculated for both sockets in each aspect of the study. Both socket type (p=0.002) and location on the socket (p=0.014) were statistically significant factors affecting the temperature difference between inner and outer socket walls. Compared with the control socket, the modified socket containing a helical cooling channel exhibited greater temperature differences across its wall of 11.1 °C and 6.4 °C in the computer simulations and bench-top testing, respectively. This finding suggested that socket modifications, such as the cooling channel presented, could provide a beneficial cooling effect to an amputee patient's residual limb.

  6. The Design, Implementation, and Performance Evaluation of Secure Socket SCTP 2.0

    OpenAIRE

    Hasselström, Nicklas; Hjern, Gunnar; Hoorn, Richard; Hult, Marcus; Häger, Johan; Syren, Jens; Alfredsson, Stefan; Lindskog, Stefan

    2015-01-01

    The Stream Control Transmission Protocol (SCTP) is acomparatively new transport protocol that presents some advanced features compared to other standardized transport protocols. However, there are currently no standardized end-to-end security solutions suited for SCTP. One proposal for end-to-end encryption is the Secure Socket SCTP (S2-SCTP) protocol, developed by researchers at Karlstad University.  The security solution for SCTP described in this report uses key agreement for obtaining key...

  7. Surgical Protocol and Short-Term Clinical Outcome of Immediate Placement in Molar Extraction Sockets Using a Wide Body Implant

    Directory of Open Access Journals (Sweden)

    Stefan Vandeweghe

    2011-08-01

    Full Text Available Objectives: Implant placement in molar extraction sockets can be difficult due to complex multi-root anatomy and the lack of predictable primary stability. The aim of this study was to evaluate the outcome of an 8 - 9 mm diameter tapered implant, designed to be placed in molar extraction sockets.Material and methods: Patients treated at least 1 year before with a Max® implant (Southern Implants, Irene, South Africa were invited for a clinical examination. Variables collected were surgical and prosthetic protocol, implant dimension and smoking habits. Peri-implant bone level was determined on peri-apical radiographs and compared to baseline, being implant insertion.Results: 98 implants had been placed in 89 patients. One implant had failed. Thirty eight patients representing 47 implants (maxilla 26, mandible 21 were available for clinical examination. Mean bone loss was 0.38 mm (SD 0.48; range - 0.50 – 1.95 after a mean follow-up of 20 months (range 12 - 35. Implant success was 97.9%. Around 30 implants, a bone substitute was used to fill the residual space, but this did not affect the bone loss outcome. Bone loss was only significantly different between maxilla and mandible (0.48 mm vs. 0.27 mm and between the 8 and 9 mm diameter implants (0.23 mm vs. 0.55 mm. A full papilla was present at 71% of the interproximal sites and irrespective of bone loss.Conclusions: The Max® implant demonstrated good primary stability, when placed in molar extraction sockets, with limited bone loss over time.

  8. The use of Osseointegration and Orbital Implants in the Management of Orbital Exenteration or Severe Contracted Sockets

    Directory of Open Access Journals (Sweden)

    Emine Esra Karaca

    2014-03-01

    Full Text Available Objectives: To evaluate the results of bony integrated implants used in the management of exenterated or contracted sockets. Materials and Methods: Ten eyes of 10 cases underwent bony integrated implants for the management of exenterated (7 eyes or contracted (3 eyes sockets. The procedure was performed in two steps in a two-month period. The first step included placement of screws by preparing the osteotomy site, whereas the second step included implantation of magnetic implants over these screws that will adhere to the orbital implant. The patients were retrospectively evaluated for age, gender, etiology, surgical timing, history of radiotherapy, and time of application of epithesis. The presence of infection at the surgical site, implant loss, functional or cosmetic problems at the perisurgical area, the usage of epithesis during the social life were evaluated. Results: There were 7 female and 3 male patients. The mean age was 34 (5-75 years. The indications for enucleation or exenteration were: retinoblastoma (4 cases, malignant melanoma (2 cases, basal cell carcinoma (1 case, squamous cell carcinoma (1 case, rhabdomyosarcoma (1 case and sinoorbital mucormycosis (1 case. The epitheses were applied 3 to 156 months (mean 51 months following the intervention. All of the implantations were performed successfully. During follow-up, one case had lost the implant and one case had local infection that responded to antibiotic treatment. Three cases were reoperated and the implants were replaced after a 2-year follow-up time due to the deterioration of the magnetic effect of the implants. Conclusion: Bony integrated orbital implants have an important role in solution of esthetic problems encountered in the exenterated orbit and severe contracted socket. (Turk J Ophthalmol 2014; 44: 127-31

  9. Effects of low-level laser therapy on orthodontic tooth movement and root resorption after artificial socket preservation

    Directory of Open Access Journals (Sweden)

    Massoud Seifi

    2014-01-01

    Full Text Available Background: Low- level laser therapy has been used to stimulate the orthodontic tooth movements (OTM previously. Furthermore, in the orthodontic treatments accompanying tooth extractions, the adjacent teeth move towards the extraction sites and close the space in some cases. Then, the adjacent tooth movements must be prevented in the treatments requiring space. Laser stimulates and at some doses decelerates tooth movement; it also improves healing process and enhances osteogenesis. Hence, it can prevent movement by osteogenesis adjacent to the tooth. The present study investigated the effects of low-level laser therapy on the OTM and root resorption following artificial socket preservation. Materials and Methods: In this experimental animal trial, 16 male albino rabbits were selected with similar characteristics and randomly divided in two groups. Under general anesthesia, an artificial socket, 8 mm in height, was created in the mesial aspect of the first premolars of the rabbits and filled with demineralized freeze dried bone allograft (DFDBA. The first premolars were connected to the incisors using nickel titanium coil springs. In experimental group, gallium-aluminum-arsenide (GaAlAs laser was irritated mesial to first premolar where artificial socket was created continuously (808 nm. The cycle was 10 days irritation, 14 days rest, 10 days irritation, 14 days rest (Biostimulation mode. Control group was not laser irradiated. All animals were sacrificed after 48 days and the distance between the distal aspect of the first premolars, and the mesial surface of the second premolars was measured with leaf gauge. The specimens underwent histological assessments. Integrity of root and its resorption was observed under microscope calibration. The size of resorption lacunae was calculated in mm 2 . Normality of data was proved according to Kolmogorov-Smirnov analysis, and Student′s t-test was done. P value less than 0.05 was considered as significant

  10. Web-based control application using WebSocket

    International Nuclear Information System (INIS)

    The WebSocket allows asynchronous full-duplex communication between a Web-based (i.e. Java Script-based) application and a Web-server. WebSocket started as a part of HTML5 standardization but has now been separated from HTML5 and has been developed independently. Using WebSocket, it becomes easy to develop platform independent presentation layer applications for accelerator and beamline control software. In addition, a Web browser is the only application program that needs to be installed on client computer. The WebSocket-based applications communicate with the WebSocket server using simple text-based messages, so WebSocket is applicable message-based control system like MADOCA, which was developed for the SPring-8 control system. A simple WebSocket server for the MADOCA control system and a simple motor control application were successfully made as a first trial of the WebSocket control application. Using Google-Chrome (version 13.0) on Debian/Linux and Windows 7, Opera (version 11.0) on Debian/Linux and Safari (version 5.0.3) on Mac OS X as clients, the motors can be controlled using a WebSocket-based Web-application. Diffractometer control application use in synchrotron radiation diffraction experiment was also developed. (author)

  11. Evaluating WebSocket and WebRTC in the Context of a Mobile Internet of Things Gateway

    OpenAIRE

    Karadogan, Günay Mert

    2014-01-01

    This thesis project explores two well-known real-time web technologies: WebSocket and WebRTC. It explores the use of a mobile phone as a gateway to connect wireless devices with short range of radio links to the Internet in order to foster an Internet of Things (IoT). This thesis project aims to solve the problem of how to collect real-time data from an IoT device, using the Earl toolkit. With this thesis project an Earl device is able to send real-time data to Internet connected devices and ...

  12. 铝合金控制臂球头销旋铆工艺有限元分析%Simulation on the Ball Joint Sealing of Aluminum Control Arms

    Institute of Scientific and Technical Information of China (English)

    田浩彬; 李学磊; 刘晓航; 苑文婧; 鲁成伟

    2012-01-01

      汽车控制臂球头销封装是汽车底盘零件装配中的重要一环,其装配质量直接影响到汽车转向部件的寿命。采用有限元分析方法对铝合金控制臂球头销的旋铆封装技术进行了研究,对旋铆过程中铝合金控制臂的变形及受力情况进行了分析,并通过试验方法进行了验证,为汽车控制臂球头销的整体封装提供了有效的技术支持。%  Ball joint sealing of aluminum control arms is one of the key processes to the assembly of automobile chassis, which directly influents the life cycle of steering systems of automobiles. The revolving-reveting process for ball joint of control arms is studied by finite element method, and the deformation of housing is advanced and verified by experiments, which can provide technical support to the ball joint sealing of automobile control arms.

  13. Advanced trans-tibial socket fabrication using selective laser sintering.

    Science.gov (United States)

    Rogers, Bill; Bosker, Gordon W; Crawford, Richard H; Faustini, Mario C; Neptune, Richard R; Walden, Gail; Gitter, Andrew J

    2007-03-01

    There have been a variety of efforts demonstrating the use of solid freeform fabrication (SFF) for prosthetic socket fabrication though there has been little effort in leveraging the strengths of the technology. SFF encompasses a class of technologies that can create three dimensional objects directly from a geometric database without specific tooling or human intervention. A real strength of SFF is that cost of fabrication is related to the volume of the part, not the part's complexity. For prosthetic socket fabrication this means that a sophisticated socket can be fabricated at essentially the same cost as a simple socket. Adding new features to a socket design becomes a function of software. The work at The University of Texas Health Science Center at San Antonio (UTHSCSA) and University of Texas at Austin (UTA) has concentrated on developing advanced sockets that incorporate structural features to increase comfort as well as built in fixtures to accommodate industry standard hardware. Selective laser sintering (SLS) was chosen as the SFF technology to use for socket fabrication as it was capable of fabricating sockets using materials appropriate for prosthetics. This paper details the development of SLS prosthetic socket fabrication techniques at UTHSCSA/UTA over a six-year period.

  14. 基于Socket实现Android(java)与C#的同步通信%Socket Realization Android (java) and C # Based on Synchronous Communication

    Institute of Scientific and Technical Information of China (English)

    何诚; 邵乾飞; 袁浩; 董理; 夏得玉

    2015-01-01

    A communication mechanism based on Socket, expounds the Java and the C# language to communicate with each other through Socket programming steps, and gives the framework of the Socket communication system of a C/S model, the framework to solve the problem of communication between USB connection through the Android Windows application and desktop application, reached a mutual different platform ifle and different language object.%基于Socket的通信机制,阐述了Java和C#语言通过Socket编程来互相通信的步骤,并给出了一种C/S模式的Socket通信系统框架,该框架解决了通过USB连接的安卓应用和Windows桌面应用之间通信的问题,达到了不同平台下文件和不同语言的对象的互传。

  15. Verification of BGA type FPGA logic applied to a control equipment with Safety Class using the special socket

    Energy Technology Data Exchange (ETDEWEB)

    Chung, YounHu; Yoo, Kwanwoo; Lee, Myeongkyun; Yun, Donghwa [PONUTech Co., Seoul (Korea, Republic of)

    2015-10-15

    This article aims to provide the verification method for BGA-type FPGA of Programmable Logic Controller (PLC) developed as Safety Class. The logic of FPGA in the control device with Safety Class is the circuit to control overall logic of PLC. This device converts to the different module from the input signals for both digital and analogue of the equipment in the field and outputs their data. In addition, it should perform the logical controls such as backplane communication control and data communication. We suggest acquiring method of the data signal with efficient logic using the socket in this article. Proposed test socket is made by simpler process than former one, and the process is done in batches by which cost can be reduces, and the test socket can be quickly produced in response to any request. Also, it is possible to reduce the wear by reducing the contact force of the ball phenomenon. The structure on the basis of silicon can be reduced the modification, and it has excellent linearity. At the logic verification, the operation that state data block is designed in the FPGA could be easily confirmed by using a socket.

  16. Computer-socket manufacturing error: How much before it is clinically apparent?

    Directory of Open Access Journals (Sweden)

    Joan E. Sanders, PhD

    2012-06-01

    Full Text Available The purpose of this research was to pursue quality standards for computer-manufacturing of prosthetic sockets for people with transtibial limb loss. Thirty-three duplicates of study participants’ normally used sockets were fabricated using central fabrication facilities. Socket-manufacturing errors were compared with clinical assessments of socket fit. Of the 33 sockets tested, 23 were deemed clinically to need modification. All 13 sockets with mean radial error (MRE greater than 0.25 mm were clinically unacceptable, and 11 of those were deemed in need of sizing reduction. Of the remaining 20 sockets, 5 sockets with interquartile range (IQR greater than 0.40 mm were deemed globally or regionally oversized and in need of modification. Of the remaining 15 sockets, 5 sockets with closed contours of elevated surface normal angle error (SNAE were deemed clinically to need shape modification at those closed contour locations. The remaining 10 sockets were deemed clinically acceptable and not in need modification. MRE, IQR, and SNAE may serve as effective metrics to characterize quality of computer-manufactured prosthetic sockets, helping facilitate the development of quality standards for the socket manufacturing industry.

  17. Accuracy Verification of Magnetic Resonance Imaging (MRI) Technology for Lower-Limb Prosthetic Research: Utilising Animal Soft Tissue Specimen and Common Socket Casting Materials

    OpenAIRE

    Mohammad Reza Safari; Philip Rowe; Arjan Buis

    2012-01-01

    Lower limb prosthetic socket shape and volume consistency can be quantified using MRI technology. Additionally, MRI images of the residual limb could be used as an input data for CAD-CAM technology and finite element studies. However, the accuracy of MRI when socket casting materials are used has to be defined. A number of six, 46 mm thick, cross-sections of an animal leg were used. Three specimens were wrapped with Plaster of Paris (POP) and the other three with commercially available silico...

  18. A histomorphometric study of the effect of doxycycline and erythromycin on bone formation in dental alveolar socket of rat

    Directory of Open Access Journals (Sweden)

    Mohammad Shahabooei

    2015-01-01

    Full Text Available Background: The aim of the present study was to evaluate whether subantimicrobial doses of doxycycline (DOX and erythromycin (EM used for the treatment of peri-implant osteolysis due to their anti-osteoclastogenesis can interfere with the osseous wound healing process in rat alveolar socket. Materials and Methods: Forty-five male Wistar rats had their first maxillary right molar extracted and were divided into three groups. DOX and EM at the doses of 5 mg/kg/day orally (p.o. and 2 mg/kg/day intraperitoneally (i.p. were administered respectively to two separate groups for 7 days after operation. In the control group the animals received normal saline (5 ml/kg. Five rats were sacrificed at 7, 14 and 21 days post-extraction in each study group. A histomorphometric analysis was used to evaluate new bone formation inside the alveolar socket. Significant level was set at 0.05. Results: The findings showed that the percentage of new bone formation (NBF enhanced significantly on days 7 and 14. There was no significant difference in the NBF between DOX and EM groups. Conclusion: Short-term treatment with both DOX and EM enhanced new bone formation without any advances in favor of each drug.

  19. Hands-Off and Hands-On Casting Consistency of Amputee below Knee Sockets Using Magnetic Resonance Imaging

    Science.gov (United States)

    Rowe, Philip

    2013-01-01

    Residual limb shape capturing (Casting) consistency has a great influence on the quality of socket fit. Magnetic Resonance Imaging was used to establish a reliable reference grid for intercast and intracast shape and volume consistency of two common casting methods, Hands-off and Hands-on. Residual limbs were cast for twelve people with a unilateral below knee amputation and scanned twice for each casting concept. Subsequently, all four volume images of each amputee were semiautomatically segmented and registered to a common coordinate system using the tibia and then the shape and volume differences were calculated. The results show that both casting methods have intra cast volume consistency and there is no significant volume difference between the two methods. Inter- and intracast mean volume differences were not clinically significant based on the volume of one sock criteria. Neither the Hands-off nor the Hands-on method resulted in a consistent residual limb shape as the coefficient of variation of shape differences was high. The resultant shape of the residual limb in the Hands-off casting was variable but the differences were not clinically significant. For the Hands-on casting, shape differences were equal to the maximum acceptable limit for a poor socket fit. PMID:24348164

  20. THE BEHAVIOURAL REACTION OF WEANERS TO HANGING TOYS: WOODEN BALL AND AROMATIZED WOODEN BALL – WAY TO REDUCE AGGRESSION AFTER MIXING

    Directory of Open Access Journals (Sweden)

    Jacek NOWICKI

    2008-05-01

    Full Text Available The behaviour of weaners after mixing housed in pens equipped with hanging wooden ball, aromatized with vanilla fluid hanging wooden ball and without enrichment was evaluated. It was found that both enrichments reduced aggression, however the most interesting for weaners was the aromatized wooden ball.

  1. The Heads and Tails of Buoyant Autocatalytic Balls

    CERN Document Server

    Rogers, Michael C

    2012-01-01

    Buoyancy produced by autocatalytic reaction fronts can produce fluid flows that advect the front position, giving rise to interesting feedback between chemical and hydrodynamic effects. In a large diameter, extended cylinder that is relatively free of boundary constraints, localized initiation of an iodate-arsenous acid (IAA) reaction front on the bottom boundary generates a rising autocatalytic plume. Such plumes have several differences from their non-reactive counterparts. Using numerical simulation, we have found that if reaction is initiated using a spherical ball of product solution well above the bottom boundary, the subsequent flow can evolve much like an autocatalytic plume: the ball develops a reacting head and tail that is akin to the head and conduit of an autocatalytic plume, except that the tail is disconnected from the boundary. In the limit of large initial autocatalytic balls, however, growth of a reacting tail is suppressed and the resemblance to plumes disappears. Conversely, very small bal...

  2. Golf Ball

    Science.gov (United States)

    1998-01-01

    The Ultra 500 Series golf balls, introduced in 1995 by Wilson Sporting Goods Company, has 500 dimples arranged in a pattern of 60 spherical triangles. The design employs NASA's aerodynamics technology analysis of air loads of the tank and Shuttle orbiter that was performed under the Space Shuttle External Tank program. According to Wilson, this technology provides 'the most symmetrical ball surface available, sustaining initial velocity longer and producing the most stable ball flight for unmatched accuracy and distance.' The dimples are in three sizes, shapes and depths mathematically positioned for the best effect. The selection of dimples and their placement optimizes the interaction of opposing forces of lift and drag. Large dimples reduce air drag, enhance lift, and maintain spin for distance. Small dimples prevent excessive lift that destabilizes the ball flight and the medium size dimples blend the other two.

  3. Modeling golf ball fluid mechanics - challenges and opportunities

    Science.gov (United States)

    Squires, Kyle

    2009-11-01

    Numerical simulation presents a powerful tool for understanding the fundamental fluid mechanics that influence golf ball aerodynamics, as well as providing an approach for ultimately analyzing and designing golf balls for manufacture. Robust and accurate simulation strategies are central to providing a means to screen designs prior to costly prototyping and field measurement. Results from a hierarchy of simulation strategies applied to the flow around golf balls will be presented, ranging from Reynolds-averaged Navier-Stokes (RANS) computations to Direct Numerical Simulation (DNS). RANS methods, while leading to computationally efficient approaches, are challenged to represent using ad hoc turbulence models the subtle effects induced by surface dimpling. DNS on the other hand, offers a first-principles approach that enables detailed examination of mechanisms though carries a significant computational cost. Predictions from both techniques are contrasted; opportunities for advancing each technique are identified.

  4. Propagating $q$-field and $q$-ball solution

    CERN Document Server

    Klinkhamer, F R

    2016-01-01

    One possible solution of the cosmological constant problem involves a so-called $q$-field, which self-adjusts so as to give a vanishing gravitating vacuum energy density (cosmological constant) in equilibrium. We show that this $q$-field can manifest itself in other ways. Specifically, we establish a propagating mode ($q$-wave) in the nontrivial vacuum and find a particular soliton-type solution in flat spacetime, which we call a $q$-ball by analogy with the well-known $Q$-ball solution. Both $q$-waves and $q$-balls are expected to play a role for the equilibration of the $q$-field in the very early universe.

  5. Micro-structure and frictional characteristics of beetle's joint

    Institute of Scientific and Technical Information of China (English)

    DAI Zhendong; Stanislav N. Gorb

    2004-01-01

    Geometric and micro-structure design, tribology properties of beetle joints were experimentally studied, which aimed to enlighten ideas for the joint design of MEMS.The observation by using SEM and microscopy suggested that beetle's joints consist of a concave surface matched with a convex surface. The heads of the beetles, rubbing with flat glass, were tested in fresh and dried statuses and compared with sapphire ball with flat glass. Frictional coefficient of the joint material on glass was significantly lower than that of the sapphire sphere on glass. The material of the joint cuticle for convex surface is rather stiff (the elastic modulus 4.5 Gpa) and smooth. The surface is hydrophobic (the contact angle of distilled water was 88.3° ). It is suggested here that the high stiffness of the joint material and hydrophobicity of the joint surface are parts of the mechanism minimizing friction in insect joints.

  6. Holy balls!

    Science.gov (United States)

    Truscott, Tadd; Belden, Jesse

    2011-11-01

    Why can some balls walk on water while others cannot? We investigate the rebound dynamics of elastic spheres impacting on a free-surface. Several variables determine whether or not a sphere will bounce when impacting a free-surface including velocity, impact angle, size and elasticity. Stiff elastic spheres, such as a racquetball, successfully skip at low impact angles and high velocities, but tend not to bounce when the impact angle becomes too large. However, the more compliant Waboba (WAter BOuncing BAll) bounces marvelously even at very high impact angles. Unlike a stiffer ball, the Waboba flattens out quickly as it is forming a cavity. The cavity lip forms a ramp and the flattened ball then skips off the water surface. We demonstrate how this phenomenon surprisingly resembles a skipping stone. Using high-speed video we explore the rebound dynamics for various values of elasticity, velocity, angle and size and determine when an object will bounce off the water surface.

  7. Kicking velocity and effect on match performance when using a smaller, lighter ball in women's football

    DEFF Research Database (Denmark)

    Andersen, Thomas B.; Krustrup, Peter; Bendiksen, Mads;

    2016-01-01

    The present study evaluated the effect of a smaller, lighter ball on kicking speed and technical-tactical and physical match performance in high-level adult female footballers. In the laboratory test setting, the peak ball velocity was 6% higher with the new ball (NB) than the standard ball (SB...... in passing success rate (NB: 68±1% and SB: 68±1%, p>0.05). In conclusion, high-level adult female footballers had a higher kicking speed when using a smaller, lighter ball, but no differences were observed during match-play with the 2 ball types in respect of technical-tactical and physical match...

  8. Error Analysis and Adaptive-Robust Control of a 6-DoF Parallel Robot with Ball-Screw Drive Actuators

    OpenAIRE

    Navid Negahbani; Hermes Giberti; Enrico Fiore

    2016-01-01

    Parallel kinematic machines (PKMs) are commonly used for tasks that require high precision and stiffness. In this sense, the rigidity of the drive system of the robot, which is composed of actuators and transmissions, plays a fundamental role. In this paper, ball-screw drive actuators are considered and a 6-degree of freedom (DoF) parallel robot with prismatic actuated joints is used as application case. A mathematical model of the ball-screw drive is proposed considering the most influencing...

  9. Boric Acid Levels in Fresh Noodles and Fish Ball

    OpenAIRE

    Pang-Hung Yiu; Jian See; Amartalingam Rajan; Choon-Fah J. Bong

    2008-01-01

    Boric acid (H3BO3) is detrimental to human health if consumed in excess. However, it continues to be used in the production of food especially noodles and some processed seafood such as fish ball. Five kinds of noodles and a type of fish ball were collected over a period of four weeks from a random sample of manufacturers in Bintulu, Sarawak, Malaysia. The boric acid in these food samples were analyzed by the curcumin-acetic acid method using 2-ethyl-1, 3-hexanediol (EHD) extraction. Results ...

  10. Semi-flexible sockets for amputation below the knee.

    Science.gov (United States)

    Symington, D C; Lowe, P J; Mackay, S

    1975-09-01

    A semi-flexible socket fitted to a series of 47 consecutive below-knee amputees is evaluated, and the problems in assessing prosthetic components and appropriate methodology are discussed. The results suggest that this type of socket deserves wider use and further evaluation in active amputees, where comfort, perspiration control or the condition of the skin is interfering with the patient's function.

  11. Assessment technique for computer-aided manufactured sockets

    Directory of Open Access Journals (Sweden)

    Joan E. Sanders, PhD

    2011-08-01

    Full Text Available This article presents an assessment technique for testing the quality of prosthetic socket fabrication processes at computer-aided manufacturing facilities. The assessment technique is potentially useful to both facilities making sockets and companies marketing manufacturing equipment seeking to assess and improve product quality. To execute the assessment technique, an evaluator fabricates a collection of test models and sockets using the manufacturing suite under evaluation, then measures their shapes using scanning equipment. Overall socket quality is assessed by comparing socket shapes with electronic file (e-file shapes. To characterize carving performance, model shapes are compared with e-file shapes. To characterize forming performance, socket shapes are compared with model shapes. The mean radial error (MRE, which is the average difference in radii between the two compared shapes, provides insight into sizing quality. Interquartile range (IQR, the range of radial error for the best-matched half of the points on the compared socket surfaces, provides insight into regional shape quality. The source(s of socket shape error may be pinpointed by separately determining MRE and IQR for carving and forming. The developed assessment technique may provide a useful tool to the prosthetics community and industry to help identify problems and limitations in computer-aided manufacturing and give insight into appropriate modifications to overcome them.

  12. On the Quaternion Ball and the Quaternion Projective Space

    Institute of Scientific and Technical Information of China (English)

    Qi Keng LU

    2005-01-01

    Since the quaternion ball was used to study the AdS/CFT problems for spinor fields, it is worthwhile to study further the geometry (in sense of Klein) and analysis on it and on its extended space (in the sense of Behnke-Thullen), the quaternion projective space.

  13. 8 Pin RIC Socket for Hearing Aid Applications

    DEFF Research Database (Denmark)

    Islam, Aminul; Hansen, Hans Nørgaard; Davids, Søren;

    2012-01-01

    process and the other one is fully automated process. This paper presents the entire process chain for both the concepts and makes a comparative analysis based on the experimental investigation and validation. The work presented here can be a source of valuable information for industrial users......The current paper presents the development of an 8 Pin RIC (Receiver in the canal) Socket for hearing instruments within the framework of the COTECH project. There are 8 industrial demonstrators developed in COTECH based on the converged product and process design. Sonion’s 8 Pin RIC Socket is one...... of them. 8 Pin RIC Socket is a functionally versatile product which can combine many different functions and presents many advantages compared with the previous 3 Pin RIC Socket. For the demonstrator production of the new Socket, two different production concepts were chosen- one based on semi-automated...

  14. THE EFFECT OF GAMES AND TRAINING PROGRAMS OFFERED AT BALL SCHOOL (BALSCHULE, ON BALL-COORDINATION AMONG FIRST AND SECOND GRADE STUDENTS

    Directory of Open Access Journals (Sweden)

    Behrooz Ebrahimi

    2013-06-01

    Full Text Available The aim of this study is to investigate the effect of games and training programs offered at the Ball school (Ballschule Heidelberg, on ball-coordination among first and second grade students. For this purpose, 38 students from 13 schools covered by the Ball school (Heidelberg Balschule, were chosen as the experimental group (non-random ; in the meantime the consent of the students’ parents were also received. Forty students as well as a control group (non-random of eight normal schools were selected with parental consents. Then through using ball-coordination tests [BKT (BallKoordinationstests. Ball Coordination’s Tests], the level of the ball skills among both groups were measured in the pre-test and Post-test. Tests included kicking ball against the wall (under five conditions. The research methods were semi-experimental with experimental and control groups. Independent variables were also applied to the experimental group and the means and standard deviations were calculated through descriptive statistics. And then, a T-test for statistical analysis of data in related groups were applied. The results showed a significant effect of games and training programs offered at the school ball in the ball-coordination of subjects.

  15. Unifying representation of Bézier curve and two kinds of generalized ball curves

    Institute of Scientific and Technical Information of China (English)

    ZHU Xiaolin; WANG Zhihua

    2012-01-01

    This paper presents a new basis, the WSB basis, which unifies the Bemstein basis, Wang-Ball basis and Said-Ball basis, and therefore the Bézier curve, Wang-Ball curve and Said-Ball curve are the special cases of the WSB curve based on the WSB basis In addition, the relative degree elevation formula, recursive algorithm and conversion formula between the WSB basis and the Bern- stein basis are given.

  16. Research and implementation of instant messaging system based on WebSocket%基于WebSocket的即时通信系统研究与实现

    Institute of Scientific and Technical Information of China (English)

    张艺

    2015-01-01

    To improve the ability and efficiency of instant messaging in B/S structure,the traditional Server-Side information push technology,especially the Bidirectional-streams Over Synchronous HTTP(BOSH) technology is ana-lyzed,and the infocommunications under persistent connection technology based on WebSocket is studied.The Web-Socket protocol and the Extensible Messaging and Presence Protocol(XMPP) is combined to design and implement an instant messaging system based on WebSocket and XMPP,which supports persistent connection based on XMPP in B/S structure,Server-Side information push and state aware.Experimental results shows that the instant messaging system based on WebSocket saves more bandwidth and has less time-delay than the instant messaging system based on tradi-tional technology.%为提高B/S架构下即时通信系统的能力及效率,分析了以HTTP的全双工流技术(BOSH)为代表的传统B/S架构下服务器信息推送技术,研究了基于 WebSocket 的面向长连接信息通信技术.整合了 WebSocket 协议与可扩展通讯表示协议(XMPP),实现了一套基于WebSocket和XMPP的即时通信系统,支持基于XMPP的B/S架构下长连接会话保持、即时消息主动推送、状态感知功能.实验结果表明,基于 WebSocket 的即时通信系统比基于传统技术的即时通信系统在带宽占用、消息收发时延方面具有显著的性能优势.

  17. Effects of platelet-poor plasma, platelet-rich plasma, and platelet-rich fibrin on healing of extraction sockets with buccal dehiscence in dogs.

    Science.gov (United States)

    Hatakeyama, Ichiro; Marukawa, Eriko; Takahashi, Yukinobu; Omura, Ken

    2014-02-01

    Alveolar bone resorption generally occurs during healing after tooth extraction. This study aimed to evaluate the effects of platelet-poor plasma (PPP), platelet-rich plasma (PRP), and platelet-rich fibrin (PRF) on healing in a ridge-augmentation model of the canine socket with dehiscence of the buccal wall. The third mandibular premolars of 12 beagle dogs were extracted and a 3 mm buccal dehiscence from the alveolar crest to the buccal wall of the extraction socket was created. These sockets were then divided into four groups on the basis of the material used to fill the sockets: PPP, PRP, PRF, and control (no graft material) groups. Results were evaluated at 4 and 8 weeks after surgery. The ultrastructural morphology and constructs of each blood product were studied by a scanning electron microscope (SEM) or calculating concentrations of platelets, fibrinogen, platelet-derived growth factor, and transforming growth factor-β. A total of five microcomputed tomography images of specimens were selected for measurement, and the area occupied by the newly formed bone as well as the horizontal bone width were measured. Moreover, decalcified tissue specimens from each defect were analyzed histologically. The median area of new bone at 4 and 8 weeks and median horizontal bone width at 8 weeks were the highest in the PPP group. However, bone maturation in the PRF and the PRP groups was more progressed than that in the PPP and control groups. By SEM findings, the PRF group showed a more highly condensed fibrin fiber network that was regularly arranged when compared with the PPP and PRP groups. The growth factors released from platelets in PRP indicated higher concentrations than that in PRF. Under more severe conditions for bone formation, as in this experiment, the growth factors released from platelets had a negative effect on bone formation. This study showed that PPP is an effective material for the preservation of sockets with buccal dehiscence.

  18. 76 FR 10335 - Ball Bearings and Parts Thereof From Germany: Initiation of Antidumping Duty Changed...

    Science.gov (United States)

    2011-02-24

    ..., 75 FR 37759 (June 30, 2010). After analysis of the quantity and value of the sales of ball bearings... FR 20900 (May 15, 1989). On June 30, 2010, we initiated an administrative review of the order on ball... International Trade Administration Ball Bearings and Parts Thereof From Germany: Initiation of Antidumping...

  19. Development and implementation of EPICS channel access client with real-time web using WebSocket

    International Nuclear Information System (INIS)

    In the large experimental facilities such as KEKB, RIBF, and J-PARC, the accelerators are operated by the remote control system based on EPICS (Experimental Physics and Industrial Control System). One of the advantages in EPICS-based system is the software reusability. Because it is available to develop client system by using Channel Access (CA) protocol without protocols with hardware dependencies, even if the system consists of the various kind controllers. As next-generation OPI (Operator Interface) using CA, we develop a server for the WebSocket, which is a new protocol provided by Internet Engineering Task Force (IETF), with combination of Node.js and the modules. As a result, we are able to use Web-based client system not only in the central control room but also with various types of equipment for accelerator operation. (author)

  20. Holy balls!

    CERN Document Server

    Wright, Michael; Belden, Jesse; Truscott, Tadd

    2011-01-01

    We demonstrate the behavior of three balls skipping off of the water surface: a Superball, a racquetball, and a water bouncing ball (Waboba). The three balls have rebound coefficients of 0.9, 0.8 and 0.2, respectively. However, we notice that the Waboba bounces better than the others, but why? The Superball has a high coefficient of restitution, creating large rebounds. Here the impact is angled to the free surface, but the inelastic response and large mass ratio forces the ball underwater without skipping. The racquetball has a lower mass ratio and a more elastic response to impacts. Also thrown at a shallow angle, it bounces off of the surface of the water 1-3 times before coming to rest. The Waboba flattens inside the cavity allowing it to skip off of the surface more easily. The flattened ball looks more like a skipping stone than a sphere due to its large elastic deformation at impact. Examining the reaction of a skipping stone we see that the stone creates a cavity in which it planes, slipping out of it...

  1. Sir Robert Ball: Victorian Astronomer and Lecturer par excellence

    Science.gov (United States)

    Jones, R. I. G.

    2005-12-01

    Between 1875 and 1910 Sir Robert Stawell Ball gave an estimated 2,500 lectures in towns and cities all over the British Isles and abroad. This paper traces his lecturing career from its beginnings in Ireland to the triumphs of the Royal Institution, and on lecture tours in the United States of America. After a period in mathematics and mechanics, he became a populariser of science, especially astronomy, and found fame and fortune among the working classes and the aristocracy. What motivated him to tireless travels is uncertain, but it might have been that it was rewarding, financially and to his reputation. Whatever his motives, contemporary accounts are clear that BallÕs lectures were extremely popular and well-received.

  2. Sports injuries in adolescents' ball games: soccer, handball and basketball.

    Science.gov (United States)

    Yde, J; Nielsen, A B

    1990-03-01

    In a prospective study of 302 adolescent players in three ball games (soccer, handball and basketball), 119 incurred injuries. The injury incidence (number of injuries per 1000 playing hours) was 5.6 in soccer, 4.1 in handball and 3.0 in basketball. Ankle sprains accounted for 25 per cent of the injuries, finger sprains 32 per cent, strains in the thigh and leg 10 per cent, and tendinitis/apophysitis 12 per cent. The most serious injuries were four fractures, one anterior cruciate ligament rupture, and two meniscus lesions. The most serious injuries, with the longest rehabilitation period, occurred in soccer. In soccer, many injuries occurred during tackling and contact with an opposing player, while the injuries in handball and basketball were often caused by ball contact and running. PMID:2350669

  3. Trajectory-based ball detection and tracking with aid of homography in broadcast tennis video

    Science.gov (United States)

    Yu, Xinguo; Jiang, Nianjuan; Ang, Ee Luang

    2007-01-01

    Ball-detection-and-tracking in broadcast tennis video (BTV) is a crucial but challenging task in tennis video semantics analysis. Informally, the challenges are due to camera motion and the other causes such as the presence of many ball-like objects and the small size of the tennis ball. The trajectory-based approach proposed by us in our previous papers mainly counteracted the challenges imposed by causes other than camera motion and achieves a good performance. This paper proposes an improved trajectory-based ball detection and tracking algorithm in BTV with the aid of homography, which counteracts the challenges caused by camera motion and bring us multiple new merits. Firstly, it acquires an accurate homography, which transforms each frame into the "standard" frame. Secondly, it achieved higher accuracy of ball identification. Thirdly, it obtains the ball projection position in the real world, instead of ball location in the image. Lastly, it also identifies landing frames and positions of the ball. The experimental results show that the improved algorithm can obtain not only higher accuracy in ball identification and in ball position alike, but also ball landing frames and positions. With the intent of using homography to improve the video-based event detection for smart home we also do some experiments on acquiring the homography for home surveillance video.

  4. The head tracks and gaze predicts: how the world's best batters hit a ball.

    Directory of Open Access Journals (Sweden)

    David L Mann

    Full Text Available Hitters in fast ball-sports do not align their gaze with the ball throughout ball-flight; rather, they use predictive eye movement strategies that contribute towards their level of interceptive skill. Existing studies claim that (i baseball and cricket batters cannot track the ball because it moves too quickly to be tracked by the eyes, and that consequently (ii batters do not - and possibly cannot - watch the ball at the moment they hit it. However, to date no studies have examined the gaze of truly elite batters. We examined the eye and head movements of two of the world's best cricket batters and found both claims do not apply to these batters. Remarkably, the batters coupled the rotation of their head to the movement of the ball, ensuring the ball remained in a consistent direction relative to their head. To this end, the ball could be followed if the batters simply moved their head and kept their eyes still. Instead of doing so, we show the elite batters used distinctive eye movement strategies, usually relying on two predictive saccades to anticipate (i the location of ball-bounce, and (ii the location of bat-ball contact, ensuring they could direct their gaze towards the ball as they hit it. These specific head and eye movement strategies play important functional roles in contributing towards interceptive expertise.

  5. Casimir Energy and Vacua vor Superconducting Ball in Supergravity

    CERN Document Server

    Burinskii, A

    2002-01-01

    Casimir energy for solid conducting ball is considered on the base of some finite models. One model is physical and built of a battery of parallel metallic plates. Two finite models are based on the Higgs model of superconductivity. One of them is supersymmetric and based on the Witten field model for superconducting strings. Treatment shows that contribution of Casimir energy can be very essential for superdence state in the neutron stars and nuclear matter.

  6. Entanglement and the three-dimensionality of the Bloch ball

    Energy Technology Data Exchange (ETDEWEB)

    Masanes, Ll., E-mail: ll.masanes@gmail.com [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); Müller, M. P. [Institut für Theoretische Physik, Universität Heidelberg, Philosophenweg 19, D-69120 Heidelberg (Germany); Pérez-García, D. [Departamento de Analisis Matematico and IMI, Universidad Complutense de Madrid, 28040 Madrid (Spain); Augusiak, R. [ICFO-Institut de Ciencies Fotoniques, 08860 Castelldefels, Barcelona (Spain)

    2014-12-15

    We consider a very natural generalization of quantum theory by letting the dimension of the Bloch ball be not necessarily three. We analyze bipartite state spaces where each of the components has a d-dimensional Euclidean ball as state space. In addition to this, we impose two very natural assumptions: the continuity and reversibility of dynamics and the possibility of characterizing bipartite states by local measurements. We classify all these bipartite state spaces and prove that, except for the quantum two-qubit state space, none of them contains entangled states. Equivalently, in any of these non-quantum theories, interacting dynamics is impossible. This result reveals that “existence of entanglement” is the requirement with minimal logical content which singles out quantum theory from our family of theories.

  7. Effect of attending to a ball during a side-cut maneuver on lower extremity biomechanics in male and female athletes.

    Science.gov (United States)

    Fedie, Rebecca; Carlstedt, Kristen; Willson, John D; Kernozek, Thomas W

    2010-09-01

    Many sports associated with anterior cruciate ligament (ACL) injury require athletes attend to a ball during participation. We investigated effects of attending to a ball on lower extremity mechanics during a side-cut maneuver and if these effects are consistent for males and females. Sagittal and frontal plane hip and knee kinematics and joint moments were measured during side-cut maneuvers in 19 male and 19 female National Collegiate Athletic Association division III basketball players. Participants also experienced two side-cut conditions that required attention to a ball. Our results did not indicate that the effect of attention varies with gender. However, during side-cut conditions while attending to a ball, internal knee adductor moment was 20% greater (p = 0.03) and peak knee flexion angle was 4 degrees larger (p knee flexion (p knee abduction (p = 0.026) at initial contact during all side-cut conditions than males. Attention to a ball may affect lower extremity mechanics relevant to ACL injury. The validity of laboratory studies of lower extremity mechanics for sports that include attention to a ball may be increased if participants are required to attend to a ball during the task. PMID:21162362

  8. Oscillation and levitation of balls in continuously stratified fluids

    OpenAIRE

    Biro, I.; Gyure, B.; I. M. Janosi; Szabo, K. G.; Tel, T.

    2007-01-01

    The free motion of balls is investigated experimentally in continously stratified fluid in a finite container. The oscillation frequency is found to be very close to the local Brunt-Vaisala frequency. The effect of added mass proves to be practically negligible. The evolution of rear jets is demonstrated, and a kind of long term levitation is found. We show that the classical viscous drag would lead to a much stronger damping than observed in the experiment. This is interpreted as a consequen...

  9. Clinical and biometrical evaluation of socket preservation using demineralized freeze-dried bone allograft with and without the palatal connective tissue as a biologic membrane

    OpenAIRE

    Hamid Moghaddas; Mohammad Reza Amjadi; Narges Naghsh

    2012-01-01

    Background: Alveolar ridge preservation following tooth extraction has the ability to maintain the ridge dimensions and allow the implant placement in an ideal position fulfilling both functional and aesthetic results. The aim of this study was to evaluate the efficacy of the palatal connective tissue as a biological membrane for socket preservation with demineralized freeze-dried bone allograft (DFDBA). Materials and Methods: Twelve extraction sites were treated with DFDBA with (case gro...

  10. A molecular plug-socket connector.

    Science.gov (United States)

    Rogez, Guillaume; Ribera, Belén Ferrer; Credi, Alberto; Ballardini, Roberto; Gandolfi, Maria Teresa; Balzani, Vincenzo; Liu, Yi; Northrop, Brian H; Stoddart, J Fraser

    2007-04-18

    A monocationic plug-socket connector that is composed, at the molecular level, of three components, (1) a secondary dialkylammonium center (CH2NH2+CH2), which can play the role of a plug toward dibenzo[24]crown-8 (DB24C8), (2) a rigid and conducting biphenyl spacer, and (3) 1,4-benzo-1,5-naphtho[36]crown-10 (BN36C10), capable of playing the role of a socket toward a 4,4'-bipyridinium dicationic plug, was synthesized and displays the ability to act as a plug-socket connector. The fluorescent signal changes associated with the 1,5-dioxynaphthalene unit of its BN36C10 portion were monitored to investigate the association of this plug-socket connector with the complementary socket and plug compounds. The results indicate that (1) the CH2NH2+CH2 part of the molecular connector can thread DB24C8 in a trivial manner and (2) the BN36C10 ring of the connector can be threaded by a 1,1'-dioctyl-4,4'-bipyridinium ion only after the CH2NH2+CH2 site is occupied by a DB24C8 ring. The two connections of the three-component assembly are shown to be controlled reversibly by acid/base and red/ox external inputs, respectively. The results obtained represent a key step for the design and construction of a self-assembling supramolecular system in which the molecular electron source can be connected to the molecular electron drain by a molecular elongation cable. PMID:17388589

  11. Experimental and theoretical study of phase transitions under ball milling

    International Nuclear Information System (INIS)

    The aim of this work was to determine how phase transition s under ball-milling depend on the milling conditions and to find out if one can rationalize such transitions with the theory of driven alloys. We have chosen two phase transitions: the order-disorder transition in Fe Al and the precipitation-dissolution NiGe. In the case of Fe Al we have found that the steady-state long range order parameter achieved under ball milling intensity; moreover the same degree of order is achieved starting from an ordered alloy or a disordered solid solution. On the way to fully disordered state the degree of order either decreases monotonically or goes through a short lived transient state. This behaviour is reminiscent of a first order transition while the equilibrium transition is second order. All the above features are well reproduced by a simple model of driven alloys, which was originally build for alloys under irradiation. The stationary degree of order results of two competitive atomic jump mechanisms: the forced displacements induced by the shearing of the grains, and the thermally activated jumps caused by vacancies migrations. Finally we have performed atomistic simulations with a Monte Carlo kinetic algorithm, which revealed the role of the fluctuations in the intensity of the forcing. Moreover we have shown that specific atomistic mechanisms are active in a dilute NiGe solid solution which might lead to ball milling induced precipitation in under-saturated solid solution. (author)

  12. Life Estimation of Hip Joint Prosthesis

    Science.gov (United States)

    Desai, C.; Hirani, H.; Chawla, A.

    2014-11-01

    Hip joint is one of the largest weight-bearing structures in the human body. In the event of a failure of the natural hip joint, it is replaced with an artificial hip joint, known as hip joint prosthesis. The design of hip joint prosthesis must be such so as to resist fatigue failure of hip joint stem as well as bone cement, and minimize wear caused by sliding present between its head and socket. In the present paper an attempt is made to consider both fatigue and wear effects simultaneously in estimating functional-life of the hip joint prosthesis. The finite element modeling of hip joint prosthesis using HyperMesh™ (version 9) has been reported. The static analysis (load due to the dead weight of the body) and dynamic analysis (load due to walking cycle) have been described. Fatigue life is estimated by using the S-N curve of individual materials. To account for progressive wear of hip joint prosthesis, Archard's wear law, modifications in socket geometry and dynamic analysis have been used in a sequential manner. Using such sequential programming reduction in peak stress has been observed with increase in wear. Finally life is estimated on the basis of socket wear.

  13. The Dual Functionals for the Generalized Ball Basis of Wang-Said Type and Basis Transformation Formulas

    Institute of Scientific and Technical Information of China (English)

    Ping Jiang; Hongyi Wu; Jieqing Tan

    2006-01-01

    The generalized Ball curves of Wang-Said type with a position parameter L not only unify the Wang-Ball curves and the Said-Ball curves, but also include several useful intermediate curves. This paper presents the dual functionals for the generalized Ball basis of Wang-Said type. The relevant basis transformation formulae are also worked out.

  14. DETERMINATION OF BALL COHESIVE AND FRICTIONAL FORCES WITH TOOL AT POLISHING BETWEEN ALIGNED RINGS AND DISK

    Directory of Open Access Journals (Sweden)

    K. G. Schetnikovich

    2010-01-01

    Full Text Available The paper provides a design description of a tool used for polishing balls made of brittle materials between bottom driving disk and two rings. An external stationary ring has a ring turning of rectangular profile that helps the ring to be based directly on the balls which are to be polished and take self-aligned position in relation to tool rotation axis.  Forces acting on the balls in the points of contact with the tool with due account of friction against a separator and conditions of ball sliding along ring working surfaces are determined in the paper. Dependence for determination of stationary and driving ring load ratio when balls are sliding along two contact surfaces of the tool is ascertained in the paper. The paper contains recommendations on selection of modes for ball polishing at its initial and finishing stages.

  15. Effect of Nd:YAG laser light on post-extractive socket healing in rats treated with zoledronic acid and dexamethasone

    Science.gov (United States)

    Mergoni, Giovanni; Merigo, Elisabetta; Passerini, Pietro; Corradi, Domenico; Maestri, Roberta; Bussolati, Ovidio; Bianchi, Massimiliano; Sala, Roberto; Govoni, Paolo; Namour, Samir; Vescovi, Paolo

    2016-03-01

    Introduction The effect of low level laser therapy (LLLT) on the healing process could be useful for the prevention of post-extractive Bisphosphonate-related Osteonecrosis of the Jaws (BRONJ). The aim of the study was to investigate the effect of LLLT on the post-extractive socket healing in rats treated with zoledronic acid and dexamethasone. Material and Methods Thirty male Sprague-Dawley rats were divided in 4 groups: control group (C, n = 5), laser group (L, n = 5), treatment group (T, n = 10) and treatment plus laser group (T+L, n = 10). Rats of group T and T+L received zoledronate 0,1 mg/Kg and dexamethasone 1 mg/Kg every 2 days for 10 weeks. Rats of group C and L were infused with vehicle. After 9 weeks the first maxillary molars were extracted in all rats. Rats of groups L and T+L received laser therapy (Nd:YAG, 1064 nm, 1.25W, 15Hz, 5 min, 14.37 J/cm2) in the socket area at days 0, 2, 4 and 6 after surgery. At 8 days from extraction, the sockets were clinically assessed with a grading score and the wound area was measured with a dedicate software. Histomorphometric evaluation and western blot analysis of osteopontin and osteocalcin expression were performed. Results Group T+L showed a trend toward a better clinical grading score compared to group T (grade I 22% Vs 28 % - grade II 56% Vs 28% - grade III 22% Vs 44%, respectively). The average wound area was similar among the groups. Inhibition of osteoclastic alveolar bone resorption was found in groups T and T+L (Plaser irradiation. Conclusion Our findings suggest that laser irradiation after tooth extraction can promote osteoblast differentiation, as demonstrated by the higher expression of osteocalcin. Thus, laser irradiation could be considered a way to improve socket healing in conditions at risk for MRONJ development.

  16. Validity of method to quantify transtibial amputees’ free-living prosthetic wearing times and physical activity levels when using suction suspension sockets

    OpenAIRE

    Kit Tzu Tang, EngD; William D. Spence; Douglas Maxwell; Benedict William Stansfield, PhD

    2012-01-01

    Prostheses are prescribed to restore the mobility of people with amputated lower limbs. Monitoring the prosthesis wearing times and physical activity of prosthesis users would provide invaluable information regarding rehabilitation progress and suitability of the prosthesis. The validation of a method to determine wearing times and physical activity state, as well as strides taken, of amputees wearing suction suspension sockets is reported. Eight participants with transtibial amputation were ...

  17. Correlation between the Appearance of Neuropeptides in the Rat Trigeminal Ganglion and Reinnervation of the Healing Root Socket after Tooth Extraction

    International Nuclear Information System (INIS)

    The neuropeptide substance P (SP) modulates bone metabolism. This study examined the temporal appearance of the neuropeptides SP and brain-derived nerve growth factor (BDNF) and their receptors (neurokinin-1 receptor (NK1-R) and Trk B, respectively) in the rat trigeminal ganglion to investigate the role of neuropeptides in healing after tooth extraction. Rats were anesthetized and their upper right first molars were extracted; the rats were sacrificed 3 hours and 1–21 days after extraction. Their trigeminal ganglion and maxilla were removed, and cryosections were prepared and immunostained using specific antibodies against SP, BDNF, NK1-R, and Trk B. In the tooth sockets after extraction, new bone and a few SP-immunoreactive nerve fibers were first seen at day 7, and bone completely filled the sockets at day 21. In the trigeminal ganglion, the proportions of NK1-R-, BDNF-, and Trk B-immunoreactive neurons changed similarly, i.e., they initially decreased, increased rapidly to maximum levels by day 3, and then decreased gradually to control levels until 21 days. These findings suggest that the appearance of neuropeptides in the trigeminal ganglion, the reinnervation of SP-immunoreactive nerve fibers, and bone repair in the tooth socket during healing after extraction were correlated

  18. Validity of method to quantify transtibial amputees’ free-living prosthetic wearing times and physical activity levels when using suction suspension sockets

    Directory of Open Access Journals (Sweden)

    Kit Tzu Tang, EngD

    2012-04-01

    Full Text Available Prostheses are prescribed to restore the mobility of people with amputated lower limbs. Monitoring the prosthesis wearing times and physical activity of prosthesis users would provide invaluable information regarding rehabilitation progress and suitability of the prosthesis. The validation of a method to determine wearing times and physical activity state, as well as strides taken, of amputees wearing suction suspension sockets is reported. Eight participants with transtibial amputation were fitted with custom-made suction sockets. Analysis algorithms were used to automatically characterize physical activity based on the pressure at the socket’s relief valve. The algorithms were validated in a laboratory-based protocol that included walking, stair climbing, standing, sitting, donning, and doffing. Intraclass correlation coefficient (2,1 values of >0.98 were achieved with mean differences of –2.0%, 0.3%, 1.3%, and 0.7% for agreement between "off," "static," and "dynamic" times and stride count, respectively, as determined by the analysis algorithms and a concurrent video analysis. This study demonstrates that an interpretation of the pressure at the pressure-relief valve of suction suspension sockets can be used to determine wearing times and activity state.

  19. Prevalence of malformations of the hip joint and their relationship to sex, groin pain, and risk of osteoarthritis: a population-based survey

    DEFF Research Database (Denmark)

    Gosvig, Kasper Kjaerulf; Jacobsen, Steffen; Sonne-Holm, Stig;

    2010-01-01

    deformity (risk ratio, 2.2). Acetabular dysplasia and the subject's sex were not found to be significant risk factors for the development of hip osteoarthritis (p = 0.053 and p = 0.063, respectively). The prevalence of hip osteoarthritis was 9.5% in men and 11.2% in women. The prevalence of concomitant...... the county of Østerbro, Copenhagen, Denmark. The inclusion criteria for this study were met by 1332 men and 2288 women. On the basis of radiographic criteria, the hips were categorized as being without malformations or as having an abnormality consisting of a deep acetabular socket, a pistol grip...... deformity, or a combination of a deep acetabular socket and a pistol grip deformity. Hip osteoarthritis was defined radiographically as a minimum joint-space width of 0.13). A deep acetabular socket was a significant risk factor for the development of osteoarthritis (risk ratio, 2.4), as was a pistol grip...

  20. Examination of anticipated chemical shift and shape distortion effect on materials commonly used in prosthetic socket fabrication when measured using MRI: a validation study.

    Science.gov (United States)

    Safari, Mohammad Reza; Rowe, Philip; Buis, Arjan

    2013-01-01

    The quality of lower-limb prosthetic socket fit is influenced by shape and volume consistency during the residual limb shape-capturing process (i.e., casting). Casting can be quantified with magnetic resonance imaging (MRI) technology. However, chemical shift artifact and image distortion may influence the accuracy of MRI when common socket/casting materials are used. We used a purpose-designed rig to examine seven different materials commonly used in socket fabrication during exposure to MRI. The rig incorporated glass marker tubes filled with water doped with 1 g/L copper sulfate (CS) and 9 plastic sample vials (film containers) to hold the specific material specimens. The specimens were scanned 9 times in different configurations. The absolute mean difference of the glass marker tube length was 1.39 mm (2.98%) (minimum = 0.13 mm [0.30%], maximum = 5.47 mm [14.03%], standard deviation = 0.89 mm). The absolute shift for all materials was <1.7 mm. This was less than the measurement tolerance of +/-2.18 mm based on voxel (three-dimensional pixel) dimensions. The results show that MRI is an accurate and repeatable method for dimensional measurement when using matter containing water. Additionally, silicone and plaster of paris plus 1 g/L CS do not show a significant shape distortion nor do they interfere with the MRI image of the residual limb.

  1. Examination of anticipated chemical shift and shape distortion effect on materials commonly used in prosthetic socket fabrication when measured using MRI: A validation study

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Safari, PhD

    2013-02-01

    Full Text Available The quality of lower-limb prosthetic socket fit is influenced by shape and volume consistency during the residual limb shape-capturing process (i.e., casting. Casting can be quantified with magnetic resonance imaging (MRI technology. However, chemical shift artifact and image distortion may influence the accuracy of MRI when common socket/casting materials are used. We used a purpose-designed rig to examine seven different materials commonly used in socket fabrication during exposure to MRI. The rig incorporated glass marker tubes filled with water doped with 1 g/L copper sulfate (CS and 9 plastic sample vials (film containers to hold the specific material specimens. The specimens were scanned 9 times in different configurations. The absolute mean difference of the glass marker tube length was 1.39 mm (2.98% (minimum = 0.13 mm [0.30%], maximum = 5.47 mm [14.03%], standard deviation = 0.89 mm. The absolute shift for all materials was <1.7 mm. This was less than the measurement tolerance of +/–2.18 mm based on voxel (three-dimensional pixel dimensions. The results show that MRI is an accurate and repeatable method for dimensional measurement when using matter containing water. Additionally, silicone and plaster of paris plus 1 g/L CS do not show a significant shape distortion nor do they interfere with the MRI image of the residual limb.

  2. FGC-15D large-diameter DTH air hammer drilling system and its application in offshore rock-socketed pile hole drilling

    Institute of Scientific and Technical Information of China (English)

    Kun YIN; Jianming PENG; Maosen WANG; Zhanjiang ZHOU

    2006-01-01

    In the past two decades, numerous large-diameter rock-socketed piles were constructed in China to support foundations of skyscrapers, great bridges or to retain soil in potential geological hazard areas. However, drilling large-diameter rock-socketed pile holes with conventional drilling method such as rotary drilling or cable tool drilling is time-consuming and the cost is usually very high. In order to drill large-diameter rock-socketed pile holes faster at relatively low cost, the FGC15A large-diameter DTH air hammer drilling system was developed in 1987 and was given the second-class award by Ministry of Geology and Mineral Resources in 1991. Since it was innovated the drilling system has been used in more than twenty important and tough projects on land, and wonderful results were acquired. At the same time the large-diameter DTH air hammer drilling system was improved continuously. The FGC15D is the latest version of the technique.

  3. The association between lower limb biomechanics and ball release speed in cricket fast bowlers: a comparison of high-performance and amateur competitors.

    Science.gov (United States)

    Middleton, Kane J; Mills, Peter M; Elliott, Bruce C; Alderson, Jacqueline A

    2016-09-01

    The aim of this study was to compare the associations between lower limb biomechanics and ball release speed in 15 high-performance (HP) and 15 amateur fast bowlers. Kinematic and kinetic variables of the lower limbs collected in the laboratory environment with a 3D Vicon motion analysis system were compared between groups, as well as their associations with ball release speed. HP bowlers had a significantly higher run-up velocity at back foot impact but this difference became non-significant at ball release. Front knee kinematics were not statistically different, however effect sizes revealed medium-large differences with the HP group displaying a more extended knee joint at maximum flexion (d = 0.72) and ball release (d = 0.76). Only front hip positive power was significantly higher in the HP group and it was suggested that the probable cause was the HP bowlers having less knee flexion after front foot impact. From a joint power analysis, the extensor muscle groups of the hip and knee were shown to be important in developing ball release speed. This highlights the need for lower limb/core strength programmes to be multifaceted and focus on the muscles associated with both power and stability.

  4. The association between lower limb biomechanics and ball release speed in cricket fast bowlers: a comparison of high-performance and amateur competitors.

    Science.gov (United States)

    Middleton, Kane J; Mills, Peter M; Elliott, Bruce C; Alderson, Jacqueline A

    2016-09-01

    The aim of this study was to compare the associations between lower limb biomechanics and ball release speed in 15 high-performance (HP) and 15 amateur fast bowlers. Kinematic and kinetic variables of the lower limbs collected in the laboratory environment with a 3D Vicon motion analysis system were compared between groups, as well as their associations with ball release speed. HP bowlers had a significantly higher run-up velocity at back foot impact but this difference became non-significant at ball release. Front knee kinematics were not statistically different, however effect sizes revealed medium-large differences with the HP group displaying a more extended knee joint at maximum flexion (d = 0.72) and ball release (d = 0.76). Only front hip positive power was significantly higher in the HP group and it was suggested that the probable cause was the HP bowlers having less knee flexion after front foot impact. From a joint power analysis, the extensor muscle groups of the hip and knee were shown to be important in developing ball release speed. This highlights the need for lower limb/core strength programmes to be multifaceted and focus on the muscles associated with both power and stability. PMID:27088598

  5. 插座防脱技术研究与应用%Research and Application of Self-locking Technology of Socket

    Institute of Scientific and Technical Information of China (English)

    蔡映峰

    2014-01-01

    Self-locking socket could prevent plug being pulled out at the locking mode, and the plug would be pulled out normally at its unlocking mode. In a certain occasion, this kind of socket could reduce the dangerous accident effectively by preventing running equipment sud-denly being power off due to loosen power connection. In this paper, it analyzes several solu-tions for self-locking socket, elaborates the key technology, self-locking principle, theoret-ical calculation as well as the difficulties and technical solution of structure design based on design requirement. It provides the theory basis for products design.%防脱插座是一种插头在锁定状态下可方便插入不易拔出,解锁状态下又能容易拔出的插座,这在某些场合可有效防止用电设备因掉电引起的事故或危害。本文根据设计要求分析了插座防脱的各种技术方案,阐述了实施例中的关键技术、自锁原理、设计计算以及结构设计中的难点和解决办法,为防脱插座的产品设计提供了理论基础。

  6. Effects and mechanism of ball milling on torrefaction of pine sawdust.

    Science.gov (United States)

    Gong, Chunxiao; Huang, Jing; Feng, Chen; Wang, Guanghui; Tabil, Lope; Wang, Decheng

    2016-08-01

    The effects and mechanism of ball milling on the torrefaction process were studied. Ball- and hammer-milled (screen size 1mm) pine sawdust samples were torrefied at three temperatures (230, 260, and 290°C) and two durations (30 and 60min) to investigate into their torrefaction behavior and physicochemical properties. The results showed that, under identical torrefaction conditions, torrefied ball-milled pine sawdust had a higher carbon content and fixed carbon, and lower hydrogen and oxygen contents than torrefied hammer-milled pine sawdust. Torrefied ball-milled pine sawdust produced lower mass and energy yields, but higher heating values than torrefied hammer-milled pine sawdust. Ball milling destroyed the crystalline structure of cellulose and thus reduced the thermal stability of hemicellulose, cellulose, and lignin, causing them to degrade at relatively lower temperatures. In conclusion, biomass pretreated with a combination of ball milling and torrefaction has the potential to produce an alternative fuel to coal.

  7. Effects and mechanism of ball milling on torrefaction of pine sawdust.

    Science.gov (United States)

    Gong, Chunxiao; Huang, Jing; Feng, Chen; Wang, Guanghui; Tabil, Lope; Wang, Decheng

    2016-08-01

    The effects and mechanism of ball milling on the torrefaction process were studied. Ball- and hammer-milled (screen size 1mm) pine sawdust samples were torrefied at three temperatures (230, 260, and 290°C) and two durations (30 and 60min) to investigate into their torrefaction behavior and physicochemical properties. The results showed that, under identical torrefaction conditions, torrefied ball-milled pine sawdust had a higher carbon content and fixed carbon, and lower hydrogen and oxygen contents than torrefied hammer-milled pine sawdust. Torrefied ball-milled pine sawdust produced lower mass and energy yields, but higher heating values than torrefied hammer-milled pine sawdust. Ball milling destroyed the crystalline structure of cellulose and thus reduced the thermal stability of hemicellulose, cellulose, and lignin, causing them to degrade at relatively lower temperatures. In conclusion, biomass pretreated with a combination of ball milling and torrefaction has the potential to produce an alternative fuel to coal. PMID:27136611

  8. Evaluation of stability of immediately placed implants in infected sockets

    Directory of Open Access Journals (Sweden)

    Uma Shankar Pal

    2013-01-01

    Full Text Available Purpose: To describe a protocol for the immediate placement of implant into the infected alveolar socket. Materials and Methods: In this study, a total number of 40 implants were placed immediately into the extraction sockets. Each case had a different periapical condition (acute, endodontic and periodontal infection. Great care had been taken in debridement of the socket, extraction of tooth/teeth and guided bone regeneration along with the use of pre-operative and post-operative anti-microbial agent. Results: All except three implants were osseo-integrated within 6 months to 1 year. The complications were due to the extraction procedure and bone regeneration process. Conclusion: Predisposing factors for failures are incomplete debridement of the socket, poor oral hygiene, incomplete closure of the wound, and systemic factors like hormones. From this study, we may conclude that immediate implants are a viable treatment option for patients with periapical infections.

  9. Prosthetic Correction of Postenucleation Socket Syndrome: A Case Report.

    Science.gov (United States)

    Kamble, Vikas B

    2014-12-01

    Postenucleation socket syndrome is a frequent late complication of enucleation of eye globe. Several pathophysiological mechanisms have been proposed to account for the symptoms of postenucleation socket syndrome, which include lost orbital volume, superior sulcus deformity, upper eyelid ptosis, lower eyelid laxity, and backward tilt of the prosthesis. The goal of postenucleation socket syndrome treatment is to achieve the best possible functional and esthetic result. The treatment can be either conservative or surgical. For the patient interested in a non-surgical correction, the conservative treatment is simple and non invasive and can be done with prosthesis modification for good positioning, comfort, and mobility. This paper describes prosthetic correction of a patient with postenucleation socket syndrome by modified ocular prosthesis.

  10. The development of a rapid prototyping prosthetic socket coated with a resin layer for transtibial amputees.

    Science.gov (United States)

    Hsu, L H; Huang, G F; Lu, C T; Hong, D Y; Liu, S H

    2010-03-01

    This article proposes a type of transtibial socket composed of an inner layer fabricated by a rapid prototyping (RP) machine and an outer layer coated with unsaturated polyester resin. This work integrates contemporary technologies including a handheld scanner and CAD systems, to design a thin primary socket shape and then manufactures the socket using a fused deposition-modeling machine. To prevent breakage caused by the layer-based forming process and to reinforce flexural strength, the current research coats the preliminary RP socket with a layer of unsaturated polyester resin. After shaping the proximal brim of the resin-reinforced RP socket to match the specific stump, this study assembles and aligns a shank and a prosthetic foot to form a prosthesis set. After completing a trial safety walk wearing the prosthesis, which is satisfactory to the amputee and a registered prosthetist, this research measures interface pressures between the stump and the resin-reinforced RP socket. Experiment results demonstrate that the resin-reinforced RP socket is applicable for transtibial amputees. In addition to strengthening the FDM socket and producing consistent socket fit, this study also demonstrates a feasible procedure that employs current technologies to design and manufacture transtibial sockets without plaster moulds.

  11. The Ball and Chain of Polyubiquitin Structures.

    Science.gov (United States)

    Alfano, Caterina; Faggiano, Serena; Pastore, Annalisa

    2016-04-01

    Ubiquitylation is a post-translational modification implicated in several different cellular pathways. The possibility of forming chains through covalent crosslinking between any of the seven lysines, or the initial methionine, and the C terminus of another moiety provides ubiquitin (Ub) with special flexibility in its function in signalling. Here, we review the knowledge accumulated over the past several years about the functions and structural features of polyUb chains. This analysis reveals the need to understand further the functional role of some of the linkages and the structural code that determines recognition of polyUbs by protein partners.

  12. Fitting of the dermis-fat grafted socket.

    Science.gov (United States)

    Przybyla, V A; La Piana, F G; Bergin, D J

    1981-09-01

    Anophthalmic orbits that reject conventional implants may accept the dermis-fat graft. The subsequent fitting of such a socket differs in many important ways from the fitting of sockets containing conventional implants. Before surgery, the ocularist should construct a custom-made scleral ring to be inserted after the operation. This replaces the standard conformer that can erode the underlying dermis. The socket must be observed carefully for any evidence of damage to the conjunctiva-dermis suture line by the ring, and the latter modified or replaced as necessary. Granulation tissue forming around the sutures uniting conjunctiva and dermis may have to be resected and cauterized. Impression molding of an artificial eye is performed five weeks after surgery. The artificial eye always requires modifications over the first six months as the graft recedes due to partial atrophy of the fat of the graft, thus deepening the socket. PMID:7029387

  13. Sports injuries in adolescents' ball games: soccer, handball and basketball.

    OpenAIRE

    Yde, J; Nielsen, A. B.

    1990-01-01

    In a prospective study of 302 adolescent players in three ball games (soccer, handball and basketball), 119 incurred injuries. The injury incidence (number of injuries per 1000 playing hours) was 5.6 in soccer, 4.1 in handball and 3.0 in basketball. Ankle sprains accounted for 25 per cent of the injuries, finger sprains 32 per cent, strains in the thigh and leg 10 per cent, and tendinitis/apophysitis 12 per cent. The most serious injuries were four fractures, one anterior cruciate ligament ru...

  14. Dimples and drag: Experimental demonstration of the aerodynamics of golf balls

    Science.gov (United States)

    Libii, Josué Njock

    2007-08-01

    While it is well known that the presence of dimples reduces the drag force exerted on a golf ball, demonstrations of this phenomenon are not common. A simple pendulum is designed and used in a wind tunnel to measure the drag force exerted by a moving stream of air on a spherical object. This pendulum is then used in experiments to measure drag forces exerted on smooth balls and on golf balls in order to compare the results. Data collected from 12 balls tested at speeds ranging from 54to180km/h demonstrate that the presence of dimples on the surface of golf balls causes them to experience drag forces that are smaller than those on smooth balls of the same diameters and weights.

  15. Toeplitz and Hankel Products on Bergman Spaces of the Unit Ball

    Institute of Scientific and Technical Information of China (English)

    Yufeng LU; Chaomei LIU

    2009-01-01

    The authors give some new necessary conditions for the boundedness of Toeplitzproducts TafTagon the weighted Bergman space A2a of the unit ball, where f and g are analytic on the unit ball. Hankel products HfH*g on the weighted Bergman space of the unit ball are studied, and the results analogous to those Stroethoff and Zheng obtained in the setting of unit disk are proved.

  16. Study on Optimizing of Ball Passing Strategy and Role Switching Mechanism for Robot Soccer

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A new ball passing strategy for robot soccer is proposed in this paper. With introduce of a new algorithm on ball passing, the optimum strategy is confirmed to be more efficient and exact when passing a ball. Questions of role switching in multi-intelligent agent cooperation in robot soccer are described based on Generalized Stochastic Petri-Net (GSPN). Results of computer simulation have confirmed the feasibility and efficiency of above Petri-net method.

  17. Testing the Effect of Hydrophilic and Hydrophobic Coatings on the Speed of a Ball through Water

    CERN Document Server

    Wiegand, Natalie

    2013-01-01

    Data is presented that confirms that hydrophobic coatings reduce friction between objects and water. The results show that the average time it took for the ball with the hydrophobic coating traveled at an average of about 6 inches per second. The ball with the hydrophilic coating traveled at a slower pace, moving at an average of about 5 inches per second and the ball without a coating traveled at an average of about 4.8 inches per second.

  18. Modelat i control d’un sistema Ball and Plate

    OpenAIRE

    Tudela Pi, Marc

    2013-01-01

    En aquest document es presenta la realització d’un projecte de control d’una planta tipus Ball and Plate. El principal objectiu consisteix en controlar la posició d’una bola damunt d’una plata. Realitzant el modelat del sistema s’ha observat que el sistema presenta un comportament no lineal i és de tipus MIMO (Multiple Input-Multiple Output). En base al model obtingut s’han dissenyat dos tipus de controladors diferents, un de tipus lineal i l’altre no lineal. Per tal de verificar el cor...

  19. A numerical and experimental study of the kinematics of a tennis ball

    Science.gov (United States)

    Navarro Sorroche, Juan

    A numerical and experimental study of the kinematics of a tennis ball. An experimental apparatus to collect data of the tennis ball in motion is designed and constructed. Data collected by the experimental apparatus is corrected by the intrinsic and extrinsic camera distortions before numeric calculation predictions of the ball's point of impact with the court are made. The experimental apparatus constructed together with comprehensive numeric computations including atmospheric conditions and spin decay, allowed making predictions of the ball's point of impact with the court with and errors <0.029%

  20. Method for loading, operating, and unloading a ball-bed nuclear reactor

    International Nuclear Information System (INIS)

    This patent describes a method of operating a ball-bed nuclear reactor with fuel element balls. Some have a fissionable material content different from that of others of the balls. It consists of: initially partly filling a reactor core with fuel balls of sufficient fissionable material content for establishing criticality and a desired level of power production at the completion of the partial filling and then, without any further filling of the reactor cavern, starting reactor operation; thereafter without any removal of fuel balls from the reactor cavern, filling fuel balls continually or in groups at relatively short intervals into the reactor cavern during increasing burning up of the fuel balls already, for compensation of the diminishing fissionable material content of the reactor core constituted by the fuel balls until a final total quantity of filling is reached; after the final filling quantity is reached and burning up has occurred, shutting down the reactor, cooling it off, releasing the pressure in the cavern, and thereafter unloading all the fuel balls from the reactor cavern, unloading being begun when the reactor is shut down and being completed before the reactor is restarted

  1. 77 FR 33159 - Ball Bearings and Parts Thereof From France, Germany, and Italy: Preliminary Results of...

    Science.gov (United States)

    2012-06-05

    ... Department published the antidumping duty orders on ball bearings and parts thereof from France (54 FR 20902), Germany (54 FR 20900), and Italy (54 FR 20903) in the ] Federal Register. On June 28, 2011, in accordance..., 71 FR 12170, 12173 (March 9, 2006), unchanged in Ball Bearings and Parts Thereof From France, et...

  2. 77 FR 53844 - Ball Bearings and Parts Thereof From France and Italy: Rescission of Antidumping Duty...

    Science.gov (United States)

    2012-09-04

    ... Duty Administrative Reviews and Request for Revocations in Part, 77 FR 40565 (July 10, 2012... International Trade Administration Ball Bearings and Parts Thereof From France and Italy: Rescission of... (the Department) initiated administrative reviews of the antidumping duty orders on ball bearings...

  3. Performance of hybrid ball bearings in oil and jet fuel

    Science.gov (United States)

    Schrader, Stephen M.; Pfaffenberger, Eugene E.

    1992-07-01

    A 308-size hybrid ball bearing, with ceramic balls and steel rings, was tested using a diester oil and gas turbine fuel as lubricants at several speeds and loads. Heat generation data from this test work was then correlated with the heat generation model from a widely used computer code. The ability of this hybrid split inner ring bearing design to endure thrust reversals, which are expected in many turbine applications, was demonstrated. Finally, the bearing was successfully endurance tested in JP-10 fuel for 25 hours at 7560 N axial load and 36,000 rpm. This work has successfully demonstrated the technology necessary to use fuel-lubricated hybrid bearings in limited-life gas turbine engine applications such as missiles, drones, and other unmanned air vehicles (UAVs). In addition, it has provided guidance for use in designing such bearing systems. As a result, the benefits of removing the conventional oil lubricant system, i.e., design simplification and reduced maintenance, can be realized.

  4. Snow ball earth and the split of Streptophyta and Chlorophyta.

    Science.gov (United States)

    Becker, Burkhard

    2013-04-01

    About 700 million years ago (Mya), the ancestor of all green plants evolved into two major groups: the Chlorophyta (many green algae) and the Streptophyta (some green algae and land plants = embryophytes). Both groups are separated by several morphological, physiological, and molecular characteristics, including different photorespiration pathways. The Chloropyhta/Streptophyta split was probably very important for the colonization of the terrestrial habitat because embryophytes, the descendants of streptophyte algae, today completely dominate the macrophyte flora of the terrestrial habitats. By contrast, in aquatic ecosystems macrophytes from brown, red, and green algae compete with embryophytes. In this opinion article, I argue that the Chlorophyta/Streptophyta split is related to glaciation events (snow ball earth states) in the Neoproterozoic and provide an explanation for the different photorespiration pathways. PMID:23102566

  5. Joint Custody and Coparenting.

    Science.gov (United States)

    Sell, Kenneth D.

    Results are presented of an intensive search of U.S. newspapers and periodicals on the joint custody of children after divorce, where both parents have continued responsibility for parenting and where the children spend part of each week, month, or year with both of the parents. Areas of concern addressed by these materials include the following:…

  6. Moisture permeability of the total surface bearing prosthetic socket with a silicone liner: is it superior to the patella-tendon bearing prosthetic socket?

    Science.gov (United States)

    Hachisuka, K; Matsushima, Y; Ohmine, S; Shitama, H; Shinkoda, K

    2001-09-01

    The purpose of this study was to examine the moisture permeability properties of materials used for total surface bearing (TSB) socket with a silicone liner, a combination of Silicone Suction Socket or Icelandic Roll-On Silicone Socket (ICEROSS) and an acrylic plastic sheet (Degaplast), patella-tendon bearing (PTB) socket, a combination of Pe-Lite and Degaplast, and wooden socket made of poplar. Moisture permeability of the socket materials was measured as the diminution of water in a container after 12 hours in a climatic chamber. Eight containers with their open, top side were uncovered (no material) or sealed with one of the socket materials; the experiment was repeated four times. One-way analysis of variance followed by Bonferroni's test was applied to examine the differences in moisture permeability. Moisture permeability levels were as follows: no material, 85.9 +/- 1.3 g; poplar, 4.3 +/- 0.4 g; Silicone Suction Socket, 1.1 +/- 0.2 g; ICEROSS, 1.0 +/- 0.2 g; Pe-Lite, 0.8 +/- 0.1 g; 3S + Degaplast, 0.8 +/- 0.1 g; ICEROSS + Degaplast, 0.8 +/- 0.2 g; and Pe-Lite + Degaplast, 0.8 +/- 0.1 g. There were significant differences between the uncovered container and the others, and between poplar and the others (P socket with a silicone liner is not superior to the PTB socket with regard to moisture permeability, and that it is necessary to develop a new prosthetic socket that allows heat release and drainage of sweat.

  7. Having a Ball with Fitness Balls

    Science.gov (United States)

    McNulty, Betty

    2011-01-01

    Fitness programs can be greatly enhanced with the addition of fitness balls. They are a fun, challenging, economical, and safe way to incorporate a cardiovascular, strength, and stretching program for all fitness levels in a physical education setting. The use of these balls has become more popular during the last decade, and their benefits and…

  8. Interface load analysis for computer-aided design of below-knee prosthetic sockets.

    Science.gov (United States)

    Reynolds, D P; Lord, M

    1992-07-01

    A finite-element analysis is made for the compression of soft tissues of the residual lower limb contained in a prosthetic socket. The analysis is relevant to static loading during stance in a patellar-tendon-bearing, below-knee design of socket. Values of Young's modulus are obtained experimentally for use in the model. One of the main objectives is to study the sensitivity of the loading to these values and also to other assumed conditions. Using direct pressure at the limb/socket interface and vertical stiffness as indicators, changes in material properties, socket alignment and socket rectification are investigated; assumptions about the frictional characteristic at the interface are seen to be critical in determination of load distribution. This type of analysis may provide the next stage of refinement for computer-aided socket design systems.

  9. The Osteogenesis Effect and Underlying Mechanisms of Local Delivery of gAPN in Extraction Sockets of Beagle Dogs

    Directory of Open Access Journals (Sweden)

    Hongcheng Hu

    2015-10-01

    Full Text Available A plastic and biodegradable bone substitute consists of poly (l-lactic-co-glycolic acid and 30 wt % β-tricalcium phosphate has been previously fabricated, but its osteogenic capability required further improvement. We investigated the use of globular adiponectin (gAPN as an anabolic agent for tissue-engineered bone using this scaffold. A qualitative analysis of the bone regeneration process was carried out using μCT and histological analysis 12 weeks after implantation. CBCT (Cone Beam Computed Tomography superimposition was used to characterise the effect of the different treatments on bone formation. In this study, we also explored adiponectin’s (APN influence on primary cultured human jaw bone marrow mesenchymal stem cells gene expressions involved in the osteogenesis. We found that composite scaffolds loaded with gAPN or bone morphogenetic protein 2 (BMP2 exhibited significantly increased bone formation and mineralisation following 12 weeks in the extraction sockets of beagle dogs, as well as enhanced expression of osteogenic markers. In vitro investigation revealed that APN also promoted osteoblast differentiation of primary cultured human jaw bone marrow mesenchymal stem cells (h-JBMMSCs, accompanied by increased activity of alkaline phosphatase, greater mineralisation, and production of the osteoblast-differentiated genes osteocalcin, bone sialoprotein and collagen type I, which was reversed by APPL1 siRNA. Therefore, the composite scaffold loaded with APN exhibited superior activity for guided bone regeneration compared with blank control or Bio-Oss® (a commercially available product. The composite scaffold with APN has significant potential for clinical applications in bone tissue engineering.

  10. Sport-Based Youth and Community Development: Beyond the Ball in Chicago

    Science.gov (United States)

    Jacobs, Jennifer M.; Castañeda, Amy; Castañeda, Rob

    2016-01-01

    Rob and Amy Castañeda, the co-founders of a sports/play-based youth and community development organization called Beyond the Ball (www.beyondtheball.org), cite the collaborative and dynamic nature of the TPSR Alliance as an important influence for their work. Beyond the Ball serves individuals between kindergarten and post-college, in the North…

  11. 48 CFR 252.225-7016 - Restriction on acquisition of ball and roller bearings.

    Science.gov (United States)

    2010-10-01

    ... of ball and roller bearings. 252.225-7016 Section 252.225-7016 Federal Acquisition Regulations System... and roller bearings. As prescribed in 225.7009-5, use the following clause: Restriction on Acquisition of Ball and Roller Bearings (MAR 2006) (a) Definitions. As used in this clause' (1)...

  12. Ball flight kinematics, release variability and in-season performance in elite baseball pitching.

    Science.gov (United States)

    Whiteside, D; McGinnis, R S; Deneweth, J M; Zernicke, R F; Goulet, G C

    2016-03-01

    The purpose of this study was to quantify ball flight kinematics (ball speed, spin rate, spin axis orientation, seam orientation) and release location variability in the four most common pitch types in baseball and relate them to in-season pitching performance. Nine NCAA Division I pitchers threw four pitching variations (fastball, changeup, curveball, and slider) while a radar gun measured ball speed and a 600-Hz video camera recorded the ball trajectory. Marks on the ball were digitized to measure ball flight kinematics and release location. Ball speed was highest in the fastball, though spin rate was similar in the fastball and breaking pitches. Two distinct spin axis orientations were noted: one characterizing the fastball and changeup, and another, the curveball and slider. The horizontal release location was significantly more variable than the vertical release location. In-season pitching success was not correlated to any of the measured variables. These findings are instructive for inferring appropriate hand mechanics and spin types in each of the four pitches. Coaches should also be aware that ball flight kinematics might not directly relate to pitching success at the collegiate level. Therefore, talent identification and pitching evaluations should encompass other (e.g., cognitive, psychological, and physiological) factors.

  13. Impact Velocity and Coefficient of Restitution for a Tennis Ball Impacting a Tennis Racquet

    OpenAIRE

    Mongkol Sukpraprut

    2015-01-01

    The impact and exit velocities of a tennis ball impacting on a fixed tennis racquet were measured with high speed video analysis to determine the coefficient of restitution (COR). It was found that there is a negative linear relationship between the COR and the impact velocity of the ball for velocities between 13 and 36 m/s.

  14. Impact Velocity and Coefficient of Restitution for a Tennis Ball Impacting a Tennis Racquet

    Directory of Open Access Journals (Sweden)

    Mongkol Sukpraprut

    2015-01-01

    Full Text Available The impact and exit velocities of a tennis ball impacting on a fixed tennis racquet were measured with high speed video analysis to determine the coefficient of restitution (COR. It was found that there is a negative linear relationship between the COR and the impact velocity of the ball for velocities between 13 and 36 m/s.

  15. Coronal plane socket stability during gait in persons with transfemoral amputation: Pilot study

    Directory of Open Access Journals (Sweden)

    Stefania Fatone, PhD, BPO(Hons

    2015-01-01

    Full Text Available Little research describes which transfemoral socket design features are important for coronal plane stability, socket comfort, and gait. Our study objectives were to (1 relate socket comfort during gait to a rank order of changes in ischial containment (IC and tissue loading and (2 compare socket comfort during gait when tissue loading and IC were systematically manipulated. Six randomly assigned socket conditions (IC and tissue compression were assessed: (1 IC and high, (2 IC and medium, (3 IC and low, (4 no IC and high, (5 no IC and medium, and (6 no IC and low. For the six subjects in this study, there was a strong negative relationship between comfort and changes in IC and tissue loading (rho = −0.89. With the ischium contained, tissue loading did not influence socket comfort (p = 0.47. With no IC, the socket was equally comfortable with high tissue loading (p = 0.36 but the medium (p = 0.04 and low (p = 0.02 tissue loading conditions decreased comfort significantly. Coronal plane hip moments, lateral trunk lean, step width, and walking speed were invariant to changes in IC and/or tissue loading. Our results suggest that in an IC socket, medial tissue loading mattered little in terms of comfort. Sockets without IC required high tissue loading to be as comfortable as those with IC, while suboptimal tissue loading compromised comfort.

  16. Coronal plane socket stability during gait in persons with transfemoral amputation: Pilot study.

    Science.gov (United States)

    Fatone, Stefania; Dillon, Michael; Stine, Rebecca; Tillges, Robert

    2014-01-01

    Little research describes which transfemoral socket design features are important for coronal plane stability, socket comfort, and gait. Our study objectives were to (1) relate socket comfort during gait to a rank order of changes in ischial containment (IC) and tissue loading and (2) compare socket comfort during gait when tissue loading and IC were systematically manipulated. Six randomly assigned socket conditions (IC and tissue compression) were assessed: (1) IC and high, (2) IC and medium, (3) IC and low, (4) no IC and high, (5) no IC and medium, and (6) no IC and low. For the six subjects in this study, there was a strong, negative relationship between comfort and changes in IC and tissue loading (rho = -0.89). With the ischium contained, tissue loading did not influence socket comfort (p = 0.47). With no IC, the socket was equally comfortable with high tissue loading (p = 0.36) but the medium (p = 0.04) and low (p = 0.02) tissue loading conditions decreased comfort significantly. Coronal plane hip moments, lateral trunk lean, step width, and walking speed were invariant to changes in IC and/or tissue loading. Our results suggest that in an IC socket, medial tissue loading mattered little in terms of comfort. Sockets without IC required high tissue loading to be as comfortable as those with IC, while suboptimal tissue loading compromised comfort.

  17. Coronal plane socket stability during gait in persons with transfemoral amputation: Pilot study.

    Science.gov (United States)

    Fatone, Stefania; Dillon, Michael; Stine, Rebecca; Tillges, Robert

    2014-01-01

    Little research describes which transfemoral socket design features are important for coronal plane stability, socket comfort, and gait. Our study objectives were to (1) relate socket comfort during gait to a rank order of changes in ischial containment (IC) and tissue loading and (2) compare socket comfort during gait when tissue loading and IC were systematically manipulated. Six randomly assigned socket conditions (IC and tissue compression) were assessed: (1) IC and high, (2) IC and medium, (3) IC and low, (4) no IC and high, (5) no IC and medium, and (6) no IC and low. For the six subjects in this study, there was a strong, negative relationship between comfort and changes in IC and tissue loading (rho = -0.89). With the ischium contained, tissue loading did not influence socket comfort (p = 0.47). With no IC, the socket was equally comfortable with high tissue loading (p = 0.36) but the medium (p = 0.04) and low (p = 0.02) tissue loading conditions decreased comfort significantly. Coronal plane hip moments, lateral trunk lean, step width, and walking speed were invariant to changes in IC and/or tissue loading. Our results suggest that in an IC socket, medial tissue loading mattered little in terms of comfort. Sockets without IC required high tissue loading to be as comfortable as those with IC, while suboptimal tissue loading compromised comfort. PMID:25629691

  18. Management of an irradiated anophthalmic socket following dermis-fat graft rejection: A case report

    OpenAIRE

    Raizada Kuldeep; Shome Debraj; Honavar Santosh

    2008-01-01

    Dermis-fat graft (DFG) is often the only promising option in cases of severely contracted sockets. However, there is an increased risk of graft failure in irradiated sockets with decreased vascularity. In such difficult cases, repeat DFG implantation also has higher risks of graft failure. We describe an ingenious method of successful management of an irradiated anophthalmic socket following DFG infection and necrosis, with acceptable cosmetic results. At surgery, an orbital impression was ta...

  19. 76 FR 58768 - Ball Bearings and Parts Thereof From France, Germany, and Italy; Amended Final Results of...

    Science.gov (United States)

    2011-09-22

    ... Reviews, 76 FR 52937 (August 24, 2011) (Final Results). The period of review is May 1, 2009, through April... International Trade Administration Ball Bearings and Parts Thereof From France, Germany, and Italy; Amended... ball bearings and parts thereof from France, Germany, and Italy. See Ball Bearings and Parts...

  20. A look into the Medical and Veterinary Entomology crystal ball.

    Science.gov (United States)

    Dantas-Torres, F; Cameron, M M; Colwell, D D; Otranto, D

    2014-08-01

    Medical and Veterinary Entomology (MVE) represents a leading periodical in its field and covers many aspects of the biology and control of insects, ticks, mites and other arthropods of medical and veterinary importance. Since the first issue of the journal, researchers working in both developed and developing countries have published in MVE, with direct impact on current knowledge in the field. An increasing number of articles dealing with the epidemiology and transmission of vector-borne pathogens have been published in MVE, reflecting rapid changes in vector distribution, pathogen transmission and host-arthropod interactions. This article represents a gaze into the crystal ball in which we identify areas of increasing interest, discuss the main changes that have occurred in the epidemiology of parasitic arthropods since the first issue of MVE, and predict the principal scientific topics that might arise in the next 25 years for scientists working in medical and veterinary entomology.

  1. 75 FR 76297 - Defense Federal Acquisition Regulation Supplement; Restriction on Ball and Roller Bearings (DFARS...

    Science.gov (United States)

    2010-12-08

    ... on May 7, 2010 (75 FR 25167). The comment period closed on July 6, 2010. Three respondents submitted... Regulation Supplement; Restriction on Ball and Roller Bearings (DFARS Case 2006-D029) AGENCY: Defense... source restriction on acquisition of ball and roller bearings. This final rule, which implements the...

  2. 75 FR 30856 - Ball Bearings From Japan and the United Kingdom

    Science.gov (United States)

    2010-06-02

    ... FR 68036 (Nov. 8, 2002). In accordance with sections 201.16(c) and 207.3 of the Commission's rules... COMMISSION [Investigation Nos. 731-TA-394-A & 399-A (Second Review) (Third Remand)] Ball Bearings From Japan... antidumping orders on ball bearings from Japan and the United Kingdom. For further information concerning...

  3. The Role of Eye and Head Movements in Detecting Information about Fly Balls

    Science.gov (United States)

    Bongers, Raoul M.; Michaels, Claire F.

    2008-01-01

    The authors attempted to identify perceptual mechanisms that pick up information for initiating a run to catch fly balls and for judging their landing locations. Fly balls have been shown to be tracked with the eyes and head (R. R. D. Oudejans, C. F. Michaels, F. C. Bakker, & K. Davids, 1999). This raised the question of whether constraining eye…

  4. Physical and Tribological Properties of Nitrided AISI 316 Stainless Steel Balls

    Directory of Open Access Journals (Sweden)

    Yang Shicai

    2016-01-01

    Full Text Available AISI 316 austenitic stainless steel balls (diameters 5.0 and 12.0 mm, typical hardness 250 HV0.3 and flat samples (20×20×2.0 mm were nitrided by a pulsed glow discharge Ar/N2 plasma. Hardness of the ball surfaces was analysed using Vickers indentation. Thermal stability of the nitrided balls (diameter 12.0 mm was studied using a furnace to heat them in air for 8 hours at temperatures up to 700.0°C and then, after cooling to room temperature, the surface hardness of the heated balls was re-measured. Scanning electron microscopy and X-ray diffraction were used to study the microstructures, composition and phase formation of the nitrided sublayers. Unlubricated pin-on-disc wear testing was used to evaluate the wear resistance of nitrided stainless steel balls (5.0 mm diameter and the results were compared with similar testing on hardened Cr-Steel balls (5 mm diameter with hardness of about 650 HV0.3. All the test results indicated that the nitrided AISI 316 austenitic stainless steel balls have advantages over the hardened Cr-Steel balls in terms of retaining high hardness after heat treatment and high resistance to sliding wear at room temperature under higher counterpart stress. These properties are expected to be beneficial for wide range of bearing applications.

  5. Ultrasonic b-scan image compounding technique for prosthetic socket design

    Science.gov (United States)

    Xue, Kefu; He, Ping; Fu, Huimin; Bismar, Hisham

    1991-11-01

    Prosthetic socket design is the most important aspect of the fit of a lower extremity prosthesis. The comfort and mobility of wearing a prosthetic socket mainly depends on the design of weight bearing characteristics of the socket. The weight bearing characteristics of a socket are determined by the relative positions among the tissues (such as bones, muscles, and fat) of the residual limb and the wall of the socket. Therefore, socket fitting cannot be guaranteed if the internal structural information of a residual limb is not made available to the prosthetist. Current prosthetic socket design and manufacture processes are disadvantaged by the inherent difficulties in determining the weight bearing characteristics of a socket due to the lack of crucial information about the internal structure of the residual limb, such as bone position, and muscle, and fat distribution. This disadvantage can be overcome through the use of an ultrasound imaging system and a computer-aided socket design system. The discussion of the complete system is out of the scope of this paper. An ultrasound imaging algorithm which provides the external shape of the limb, the bone position, and the texture pattern of the soft tissues within the limb is presented in this paper. The algorithm using the Compound B-scan imaging principle combined with geometrical transformation and statistical information faithfully measures and reconstructs with topographical shape and internal structure information of a residual limb.

  6. Contributions of Stephen J. Ball to the Research on Educational and Curriculum Policies in Brazil

    Science.gov (United States)

    Mainardes, Jefferson; Gandin, Luis Armando

    2013-01-01

    This article aims at showcasing the main contributions of Stephen J. Ball to educational research in Brazil, particularly to the study of educational and curriculum policies. We also highlight some of the limitations in the incorporation of Ball's ideas in Brazil as well as some of the challenges that these author's ideas pose to…

  7. 76 FR 327 - Ball Bearings and Parts Thereof From France: Partial Rescission of Antidumping Duty...

    Science.gov (United States)

    2011-01-04

    ..., 75 FR 37759 (June 30, 2010). Rescission of Review in Part In accordance with 19 CFR 351.213(d)(1... International Trade Administration Ball Bearings and Parts Thereof From France: Partial Rescission of... (the Department) initiated an administrative review of the antidumping duty order on ball...

  8. Collision of a Ball with a Barbell and Related Impulse Problems

    Science.gov (United States)

    Mungan, Carl E.

    2007-01-01

    The collision of a ball with the end of a barbell illustrates the combined conservation laws of linear and angular momentum. This paper considers the instructive but unfamiliar case where the ball's incident direction of travel makes an acute angle with the barbell's connecting rod. The analysis uses the coefficient of restitution generalized to…

  9. Social Media and Big Data – Cracks in the Crystal Ball?

    NARCIS (Netherlands)

    Westera, Wim

    2013-01-01

    Westera, W. (2013, 14 October). Social Media and Big Data – Cracks in the Crystal Ball? Invited e-paper at ESOMAR RW Connect. http://rwconnect.esomar.org/using-social-media-for-market-analysis-cracks-in-the-alleged-crystal-ball/

  10. Preparation and performance research of Ce-TiO2/KL ball photocatalysts

    Institute of Scientific and Technical Information of China (English)

    于晓娟; 熊领领; 马国平; 梁愿; 刘奎仁

    2014-01-01

    The Ce-TiO2/KL (diatomite) ball photocatalyst was prepared and characterized based on the pretreated diatomite. The re-sults showed that comparing with the crude diatomite, proper pretreatment could significantly improve its SiO2 purity and specific surface area. The surface of diatomite was clear with uniform pore structure and big pore size. With diatomite ball as carrier, the sup-ported Ce-TiO2/KL ball photocatalyst was prepared by sol-gel method. The photocatalytic performances of the supported Ce-TiO2/ KL ball and Ce-TiO2/KL powder photocatalysts under various preparation conditions were studied in view of photocatalytic degrada-tion rate of Rhodamine B (Rh B) solution. The degradation rate of the ball photocatalysts for Rh B reached 94.6% and could be re-used for many times, which showed much better photocatalytic performance and stability than powder photocatalysts.

  11. Using computational simulation to aid in the prediction of socket fit: a preliminary study.

    Science.gov (United States)

    Lee, Winson C C; Zhang, Ming

    2007-10-01

    This study illustrates the use of computational analysis to predict prosthetic socket fit. A simple indentation test is performed by applying force to the residual limb of a trans-tibial amputee through an indenter until the subject perceives the onset of pain. Computational finite element (FE) analysis is then applied to evaluate the magnitude of pressure underlying the indenter that initiates pain (pain threshold pressure), and the pressure at the prosthetic socket-residual limb interface. The assessment of socket fit is examined by studying whether or not the socket-limb interface pressure exceeds the pain threshold pressure of the limb. Based on the computer-aided assessment, a new prosthetic socket is then fabricated and fitted to the amputee subject. Successful socket fit is achieved at the end of this process. The approach of using computational analysis to aid in assessing socket fit allows a more efficient evaluation and re-design of the socket even before the actual fabrication and fitting of the prosthetic socket. However, more thorough investigations are required before this approach can be widely used. A subsequent part of this paper discusses the limitations and suggests future research directions in this area.

  12. Biomechanical Analysis of a Filiform Mechanosensory Hair Socket of Crickets.

    Science.gov (United States)

    Joshi, Kanishka; Mian, Ahsan; Miller, John

    2016-08-01

    Filiform mechanosensory hairs of crickets are of great interest to engineers because of the hairs' highly sensitive response to low-velocity air-currents. In this study, we analyze the biomechanical properties of filiform hairs of the cercal sensory system of a common house cricket. The cercal sensory system consists of two antennalike appendages called cerci that are situated at the rear of the cricket's abdomen. Each cercus is covered with 500-750 flow sensitive filiform mechanosensory hairs. Each hair is embedded in a complex viscoelastic socket that acts as a spring and dashpot system and guides the movement of the hair. When a hair deflects due to the drag force induced on its length by a moving air-current, the spiking activity of the neuron that innervates the hair changes and the combined spiking activity of all hairs is extracted by the cercal sensory system. Filiform hairs have been experimentally studied by researchers, though the basis for the hairs' biomechanical characteristics is not fully understood. The socket structure has not been analyzed experimentally or theoretically from a mechanical standpoint, and the characterization that exists is mathematical in nature and only provides a very rudimentary approximation of the socket's spring nature. This study aims to understand and physically characterize the socket's behavior and interaction with the filiform hair by examining hypotheses about the hair and socket biomechanics. A three-dimensional computer-aided design (CAD) model was first created using confocal microscopy images of the hair and socket structure of the cricket, and then finite-element analyses (FEAs) based on the physical conditions that the insect experiences were simulated. The results show that the socket can act like a spring; however, it has two-tier rotational spring constants during pre- and postcontacts of iris and hair bulge due to its constitutive nonstandard geometric shapes.

  13. Biomechanical Analysis of a Filiform Mechanosensory Hair Socket of Crickets.

    Science.gov (United States)

    Joshi, Kanishka; Mian, Ahsan; Miller, John

    2016-08-01

    Filiform mechanosensory hairs of crickets are of great interest to engineers because of the hairs' highly sensitive response to low-velocity air-currents. In this study, we analyze the biomechanical properties of filiform hairs of the cercal sensory system of a common house cricket. The cercal sensory system consists of two antennalike appendages called cerci that are situated at the rear of the cricket's abdomen. Each cercus is covered with 500-750 flow sensitive filiform mechanosensory hairs. Each hair is embedded in a complex viscoelastic socket that acts as a spring and dashpot system and guides the movement of the hair. When a hair deflects due to the drag force induced on its length by a moving air-current, the spiking activity of the neuron that innervates the hair changes and the combined spiking activity of all hairs is extracted by the cercal sensory system. Filiform hairs have been experimentally studied by researchers, though the basis for the hairs' biomechanical characteristics is not fully understood. The socket structure has not been analyzed experimentally or theoretically from a mechanical standpoint, and the characterization that exists is mathematical in nature and only provides a very rudimentary approximation of the socket's spring nature. This study aims to understand and physically characterize the socket's behavior and interaction with the filiform hair by examining hypotheses about the hair and socket biomechanics. A three-dimensional computer-aided design (CAD) model was first created using confocal microscopy images of the hair and socket structure of the cricket, and then finite-element analyses (FEAs) based on the physical conditions that the insect experiences were simulated. The results show that the socket can act like a spring; however, it has two-tier rotational spring constants during pre- and postcontacts of iris and hair bulge due to its constitutive nonstandard geometric shapes. PMID:27322099

  14. The effect of intermediate stop and ball size in fabrication of recycled steel powder using ball milling from machining steel chips

    International Nuclear Information System (INIS)

    A feasibility study for producing recycled steel powder from steel scrap by ball milling was carried out. Steel scrap from machining was used as a raw material and was milled using planetary ball milling. Three samples were prepared in order to study the effect of intermediate stop and ball size. Sample with intermediate stop during milling process showed finer particle size compared to the sample with continuous milling. Decrease in the temperature of the vial during the intermediate stop milling gives less ductile behaviour to the steel powder, which is then easily work-hardened and fragmented to fine powder. Mixed small and big size ball give the best production of recycled steel powder where it gives higher impact force to the scrap and accelerate the fragmentation of the steel scrap into powder. (author)

  15. Extension of Relativistic-Microwave Theory of Ball Lightning Including Long-term Losses And Stability

    CERN Document Server

    Stephan, Karl D

    2016-01-01

    After centuries, the long-standing problem of the nature of ball lightning may be closer to a solution. The relativistic-microwave theory of ball lightning recently proposed by Wu accounts for many of the leading characteristics of ball lightning, which most previous theories have failed to do. It involves the impact of a lightning-caused relativistic electron bunch to soil, producing an EM pulse that forms a plasma bubble. While the theory presents a plausible account of ball-lightning formation, storing electromagnetic energy long enough to account for the observed lifetime of such objects was not demonstrated. Here we show how such a structure can develop the high Q factor (~10^10) needed for the observed lifetimes of ~seconds for ball lightning, and show that the structure is radially stable, given certain assumptions.

  16. Electric field strength of charged conducting balls and the breakdown of the air gap between them

    Energy Technology Data Exchange (ETDEWEB)

    Saranin, Vladimir A [Department of Physics, V.G. Korolenko Glazov State Pedagogical Institute, Glazov (Russian Federation)

    2002-12-31

    Field amplification factors at the surfaces of two charged conducting balls are calculated numerically. It is shown that as the balls are brought closer together, except when their potentials are equal, the amplification factors go to infinity, and in the case of like-charged balls the field at the surface of one of them changes sign. Breakdown field strengths for the air gap between balls of a different diameter are calculated using the experimental data of other authors as the base. The results suggest that the minimum breakdown field strength is 26 kV cm{sup -1} . The author's earlier results on the interaction force between the balls are revised. (methodological notes)

  17. A comparative evaluation of extraction socket preservation with demineralized freeze-dried bone allograft alone and along with platelet-rich fibrin: A clinical and radiographic study

    Directory of Open Access Journals (Sweden)

    Dhaval J Thakkar

    2016-01-01

    Full Text Available Aims: To investigate clinically and radiographically, the bone fill in extraction sockets using demineralized freeze-dried bone allograft alone and along with platelet-rich fibrin (PRF. Materials and Methods: A randomized controlled clinical trial was carried out on 36 nonrestorable single-rooted teeth sites. Sites were randomized into demineralized freeze-dried bone allograft (DFDBA combined with PRF - test and DFDBA - control groups using a coin toss method. After the placement of graft material, collagen membrane was used to cover it. The clinical parameters recorded were ridge width and ridge height. All the parameters were recorded at baseline and at 90 and 180 days. Statistical Analysis Used: Independent t-test and paired t-test. Results: In both groups, there is significant reduction in loss of ridge width and ridge height from baseline to 90 days (P < 0.001, baseline to 180 days (P < 0.001, and 90-180 days (P < 0.001. However, when both the groups were compared the test group favored in the reduction of ridge width while there was no statistical difference in reduction of ridge height among at different intervals. Conclusions: Although DFDBA is considered as an ideal graft material, PRF can be used as an adjunctive with DFDBA for socket preservation.

  18. Actuated Ball Sports

    OpenAIRE

    Clerix, Ben

    2015-01-01

    Ball sports offer many physical, mental and social benefits, however they each require a different set of attributes, such as basketball hoops, volleyball nets, bowling pins, etc. Thus in order to play each of these ball sports, we need to provide and manually set up each of different attributes. Digital ball sports on the other hand virtualise these different attributes at the cost of losing physicality, however they have the possibility to create non-realistic experiences. Without physicali...

  19. Physics of ball sports

    Science.gov (United States)

    Cohen, C.; Clanet, C.

    2016-06-01

    Ball sports have been part of human history for thousands of years [1]. Nowadays, 13 of them are part of the Olympic games (badminton, basketball, beach volley, football/soccer, golf, handball, hockey, rugby, table tennis, tennis, volleyball, water polo, ice hockey). All these games differ by launcher (hand, club, racket, bat), ball (size, shape and mass), pitch size and number of players. These differences induce different ball velocities. Apart from the velocities and the way to maximize them, we discuss in this article the ball trajectories and their impact on the size of sports fields.

  20. Ball Milling Assisted Solvent and Catalyst Free Synthesis of Benzimidazoles and Their Derivatives.

    Science.gov (United States)

    El-Sayed, Taghreed H; Aboelnaga, Asmaa; Hagar, Mohamed

    2016-01-01

    Benzoic acid and o-phenylenediamine efficiently reacted under the green solvent-free Ball Milling method. Several reaction parameters were investigated such as rotation frequency; milling balls weight and milling time. The optimum reaction condition was milling with 56.6 g weight of balls at 20 Hz frequency for one hour milling time. The study was extended for synthesis of a series of benzimidazol-2-one or benzimidazol-2-thione using different aldehydes; carboxylic acids; urea; thiourea or ammonium thiocyanate with o-phenylenediamine. Moreover; the alkylation of benzimidazolone or benzimidazolthione using ethyl chloroacetate was also studied. PMID:27563861

  1. Ball Milling Assisted Solvent and Catalyst Free Synthesis of Benzimidazoles and Their Derivatives

    Directory of Open Access Journals (Sweden)

    Taghreed H. EL-Sayed

    2016-08-01

    Full Text Available Benzoic acid and o-phenylenediamine efficiently reacted under the green solvent-free Ball Milling method. Several reaction parameters were investigated such as rotation frequency; milling balls weight and milling time. The optimum reaction condition was milling with 56.6 g weight of balls at 20 Hz frequency for one hour milling time. The study was extended for synthesis of a series of benzimidazol-2-one or benzimidazol-2-thione using different aldehydes; carboxylic acids; urea; thiourea or ammonium thiocyanate with o-phenylenediamine. Moreover; the alkylation of benzimidazolone or benzimidazolthione using ethyl chloroacetate was also studied.

  2. Using a 3DOF Parallel Robot and a Spherical Bat to Hit a Ping-Pong Ball

    Directory of Open Access Journals (Sweden)

    Alberto Trasloheros

    2014-05-01

    Full Text Available Playing the game of Ping-Pong is a challenge to human abilities since it requires developing skills, such as fast reaction capabilities, precision of movement and high speed mental responses. These processes include the utilization of seven DOF of the human arm, and translational movements through the legs, torso, and other extremities of the body, which are used for developing different game strategies or simply imposing movements that affect the ball such as spinning movements. Computationally, Ping-Pong requires a huge quantity of joints and visual information to be processed and analysed, something which really represents a challenge for a robot. In addition, in order for a robot to develop the task mechanically, it requires a large and dexterous workspace, and good dynamic capacities. Although there are commercial robots that are able to play Ping-Pong, the game is still an open task, where there are problems to be solved and simplified. All robotic Ping-Pong players cited in the bibliography used at least four DOF to hit the ball. In this paper, a spherical bat mounted on a 3-DOF parallel robot is proposed. The spherical bat is used to drive the trajectory of a Ping-Pong ball.

  3. The WebSocket protocol and security:best practices and worst weaknesses.

    OpenAIRE

    Karlström, J. (Juuso)

    2016-01-01

    Modern web applications need reliable communication between the servers and the clients in order to access information from databases or to insert user defined input into the applications. Even today, when the web sites are something completely different from what they were originally designed to be, they still rely on the original protocols. These protocols, e.g. HTML, have been updated a few times. The transition from HTML 4.1. to HTML5 introduced many new features and techniques, such as ...

  4. A CAD CAM method for custom below-knee sockets.

    Science.gov (United States)

    Engsberg, J R; Clynch, G S; Lee, A G; Allan, J S; Harder, J A

    1992-12-01

    The purpose of this investigation was to develop a numerical method for fabricating prosthetic sockets for below-knee amputees. An optical/laser digitiser scans an amputee's stump and collects three dimensional numerical data describing the surface of the limb and describing specific modification site locations. The numerical data from the laser camera representing the stump and modification sites are altered by the prosthetist using a custom computer aided design software system running on a personal computer. Using the altered numerical data a programme is created for a high resolution numerically controlled milling machine and a mould is made. The prosthetist then fabricates a socket. While the system has been tested with below-knee amputees it has been designed for application in most areas of prosthetics and orthotics. Utilising this method 15 patients were fitted. All patients subjectively stated that their "computer designed" socket fitted better than their conventionally made socket. As the research progressed and experience was gained with the system patients were normally fitted with the first socket iteration. The system overcomes five limitations existing with some of the other numerical systems: 1) accurate high resolution surface topography, 2) specific identification of subject modification sites, 3) flexible, user friendly software, 4) high resolution numerically controlled milling, and 5) integrated expansion to other prosthetic and orthotic areas.

  5. A Tsunami Ball Approach to Storm Surge and Inundation: Application to Hurricane Katrina, 2005

    Directory of Open Access Journals (Sweden)

    Steven N. Ward

    2009-01-01

    Full Text Available Most analyses of storm surge and inundation solve equations of continuity and momentum on fixed finite-difference/finite-element meshes. I develop a completely new approach that uses a momentum equation to accelerate bits or balls of water over variable depth topography. The thickness of the water column at any point equals the volume density of balls there. In addition to being more intuitive than traditional methods, the tsunami ball approach has several advantages. (a By tracking water balls of fixed volume, the continuity equation is satisfied automatically and the advection term in the momentum equation becomes unnecessary. (b The procedure is meshless in the finite-difference/finite-element sense. (c Tsunami balls care little if they find themselves in the ocean or inundating land. (d Tsunami ball calculations of storm surge can be done on a laptop computer. I demonstrate and calibrate the method by simulating storm surge and inundation around New Orleans, Louisiana caused by Hurricane Katrina in 2005 and by comparing model predictions with field observations. To illustrate the flexibility of the tsunami ball technique, I run two “What If” hurricane scenarios—Katrina over Savannah, Georgia and Katrina over Cape Cod, Massachusetts.

  6. Accuracy Verification of Magnetic Resonance Imaging (MRI Technology for Lower-Limb Prosthetic Research: Utilising Animal Soft Tissue Specimen and Common Socket Casting Materials

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Safari

    2012-01-01

    Full Text Available Lower limb prosthetic socket shape and volume consistency can be quantified using MRI technology. Additionally, MRI images of the residual limb could be used as an input data for CAD-CAM technology and finite element studies. However, the accuracy of MRI when socket casting materials are used has to be defined. A number of six, 46 mm thick, cross-sections of an animal leg were used. Three specimens were wrapped with Plaster of Paris (POP and the other three with commercially available silicone interface liner. Data was obtained by utilising MRI technology and then the segmented images compared to corresponding calliper measurement, photographic imaging, and water suspension techniques. The MRI measurement results were strongly correlated with actual diameter, surface area, and volume measurements. The results show that the selected scanning parameters and the semiautomatic segmentation method are adequate enough, considering the limit of clinical meaningful shape and volume fluctuation, for residual limb volume and the cross-sectional surface area measurements.

  7. Accuracy verification of magnetic resonance imaging (MRI) technology for lower-limb prosthetic research: utilising animal soft tissue specimen and common socket casting materials.

    Science.gov (United States)

    Safari, Mohammad Reza; Rowe, Philip; Buis, Arjan

    2012-01-01

    Lower limb prosthetic socket shape and volume consistency can be quantified using MRI technology. Additionally, MRI images of the residual limb could be used as an input data for CAD-CAM technology and finite element studies. However, the accuracy of MRI when socket casting materials are used has to be defined. A number of six, 46 mm thick, cross-sections of an animal leg were used. Three specimens were wrapped with Plaster of Paris (POP) and the other three with commercially available silicone interface liner. Data was obtained by utilising MRI technology and then the segmented images compared to corresponding calliper measurement, photographic imaging, and water suspension techniques. The MRI measurement results were strongly correlated with actual diameter, surface area, and volume measurements. The results show that the selected scanning parameters and the semiautomatic segmentation method are adequate enough, considering the limit of clinical meaningful shape and volume fluctuation, for residual limb volume and the cross-sectional surface area measurements.

  8. Visual Servoing Tracking Control of a Ball and Plate System: Design, Implementation and Experimental Validation

    Directory of Open Access Journals (Sweden)

    Ming-Tzu Ho

    2013-07-01

    Full Text Available This paper presents the design, implementation and validation of real‐time visual servoing tracking control for a ball and plate system. The position of the ball is measured with a machine vision system. The image processing algorithms of the machine vision system are pipelined and implemented on a field programmable gate array (FPGA device to meet real‐ time constraints. A detailed dynamic model of the system is derived for the simulation study.By neglecting the high‐order coupling terms, the ball and plate system model is simplified into two decoupled ball and beam systems, and an approximate input‐ output feedback linearization approach is then used to design the controller for trajectory tracking. The designed control law is implemented on a digital signal processor (DSP. The validity of the performance of the developed control system is investigated through simulation and experimental studies. Experimental results show that the designed system functions well with reasonable agreement with simulations.

  9. Error Analysis and Adaptive-Robust Control of a 6-DoF Parallel Robot with Ball-Screw Drive Actuators

    Directory of Open Access Journals (Sweden)

    Navid Negahbani

    2016-01-01

    Full Text Available Parallel kinematic machines (PKMs are commonly used for tasks that require high precision and stiffness. In this sense, the rigidity of the drive system of the robot, which is composed of actuators and transmissions, plays a fundamental role. In this paper, ball-screw drive actuators are considered and a 6-degree of freedom (DoF parallel robot with prismatic actuated joints is used as application case. A mathematical model of the ball-screw drive is proposed considering the most influencing sources of nonlinearity: sliding-dependent flexibility, backlash, and friction. Using this model, the most critical poses of the robot with respect to the kinematic mapping of the error from the joint- to the task-space are systematically investigated to obtain the workspace positional and rotational resolution, apart from control issues. Finally, a nonlinear adaptive-robust control algorithm for trajectory tracking, based on the minimization of the tracking error, is described and simulated.

  10. Golf Balls, Boomerangs and Asteroids The Impact of Missiles on Society

    CERN Document Server

    Kaye, Brian H

    1996-01-01

    Exciting reading for anyone with a curious mind!. 'Walking one day by a golf course in Wisconsin, I was startled to hear a sharp bang as a golf ball narrowly missed my head and hit a tree. My companion cheerfully remarked, 'That could have killed you, you know.' I picked up the innocent looking little white ball and looked at it with new respect.'. Prompted by this perilous experience, Brian Kaye has written a delightful and informative book on the design and behavior of different kinds of missiles from golf balls, arrows, and slingshots to comets and rockets to outer space. You'll learn about

  11. Styrofoam-and-Velcro: An Alternative to Ball-and-Stick Models †

    OpenAIRE

    Sawyer Rowan Masonjones; Heather Dawne Masonjones; Malone, Megan C.; Anne H. Williams; Beemer, Margaret M.; Waggett, Rebecca J.

    2014-01-01

    For students learning biology at introductory levels, one of the most significant instructional barriers is their lack of preparation in chemistry. In upper-division college chemistry and biology courses, students employ ball-and-stick models in order to visualize molecular structures, but at the introductory biology level, models are inconsistently used and at the secondary level they are avoided altogether. Traditional ball-and-stick models perform poorly at all levels because they only sho...

  12. Evaluation of outer race tilt and lubrication on ball wear and SSME bearing life reductions

    Science.gov (United States)

    Kannel, J. W.; Merriman, T. L.; Stockwell, R. D.; Dufrane, K. F.

    1983-01-01

    Several aspects of the SSME bearing operation were evaluated. The possibility of elastohydrodynamics (EHD) lubrication with a cryogenic fluid was analyzed. Films as thick as .61 microns were predicted with one theory which may be thick enough to provide hydrodynamic support. The film formation, however, is heavily dependent on good surface finish and a low bulk bearing temperature. Bearing dynamics to determine if the radial stiffness of a bearing which are dependent on bearing misalignment were analyzed. Four ball tests were conducted at several environmental conditions from an LN2 bath to 426 C in air. Surface coatings and ball materials are evaluated. Severe wear and high friction are measured for all ball materials except when the balls have surface lubricant coatings.

  13. Three dimensional socket preservation: a technique for soft tissue augmentation along with socket grafting

    Directory of Open Access Journals (Sweden)

    Gholami Gholam

    2012-04-01

    Full Text Available Abstract Background A cursory review of the current socket preservation literatures well depicts the necessity of further esthetic considerations through the corrective procedures of the alveolar ridge upon and post extraction. A new technique has been described here is a rotational pedicle combined epithelialized and connective tissue graft (RPC graft adjunct with immediate guided tissue regeneration (GBR procedure. Results We reviewed this technique through a case report and discuss it’s benefit in compare to other socket preservation procedures. Conclusion The main advantages of RPC graft would be summarized as follows: stable primary closure during bone remodeling, saving or crating sufficient vestibular depth, making adequate keratinized gingiva on the buccal surface, and being esthetically pleasant.

  14. Physical Analysis of the Drag and Magnus Coefficients of the Topspin Tennis Ball

    Science.gov (United States)

    Smith, Elizabeth; Howald, Craig

    2007-05-01

    We experimentally determined the drag and Magnus coefficients of a topspin tennis ball using video analysis. Three video cameras were used to record the initial spin, projectile motion, and final spin of the ball. From these recordings the initial velocity, initial spin, final spin, horizontal acceleration, vertical acceleration, x position, and y positions of the ball were extracted. The coefficient of drag was calculated to be CD=0.6104 +/-0.06187 and the Magnus coefficient was calculated to be CM=0.6576+/-0.08767. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.OSS07.P1.14

  15. Experimental dry socket: microscopic and molecular evaluation of two treatment modalities Alveolite experimental: análise microscópica e molecular de duas modalidades de tratamento

    Directory of Open Access Journals (Sweden)

    Camila Lopes Cardoso

    2011-10-01

    Full Text Available PURPOSE: To evaluate two treatment modalities of dry socket in rats and to discuss the first findings of the molecular analysis in this experimental model. METHODS: 84 rats underwent a tooth extraction were divided in 4 groups: I-uninfected socket (control, II-infected socket without any treatment, III-infected socket treated with irrigation of 2% sodium iodide and 3% hydrogen peroxide solution, IV-infected socket submitted to curettage, irrigation with physiological saline solution and fulfilled with metronidazole paste as base. The groups were subdivided in postoperative sacrifice periods: 6/15/28 days. A quantitative and a qualitative microscopic analysis was performed. Also, a quantitative analysis was performed using a RealTimePCR to evaluate the genes expression in the wound healing: Collagen Type I/COL-I, vascular endothelial growth factor/VEGF, osteocalcin/OCN, alkaline phosphatase/ALP, runt-related transcription factor 2/RUNX2 and tumor necrosis factor alpha/TNF-α. RESULTS: The group I showed higher bone formation, followed by groups IV, III, II respectively. The group II presented higher inflammatory infiltrate and the wound healing was delayed compared with other groups. It was obtained a significant positive correlation between bone neoformation and the expression of OCN and RUNX2, inflammatory infiltrate with TNF-α and a negative correlation between bone neoformation and TNF-α. CONCLUSION: No significant difference was found between the treatments.OBJETIVO: Avaliar duas modalidades de tratamento da alveolite em ratos e discutir os primeiros achados de uma análise molecular neste modelo experimental. MÉTODOS: 84 ratos foram submetidos a uma extração dentária e foram divididos em quatro grupos: I- alvéolo não infectado (controle, II- alvéolo infectado sem tratamento, III- alvéolo infectado tratado com irrigação de iodeto de sódio a 2% e solução de peróxido de hidrogênio a 3%, IV- alvéolo infectado submetido

  16. Capillary wave formation on excited solder jet and fabrication of lead-free solder ball

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shu-guang; HE Li-jun; ZHU Xue-xin; ZHANG Shao-ming; SHI Li-kai; XU Jun

    2005-01-01

    A survey of solder ball production processes especially focusing on disturbed molten metal jet breakup process was made. Then the formation of capillary wave on tin melt jet in the way of rapid solidification was studied. A semi-empirical formula, which can be written as λ = Cvib (σ/ρ)1/3f-2/3 to predict the relationship between wavelength of capillary wave and frequency of imposed vibration was obtained. Sn-4.0Ag-0.5Cu lead free solder ball was successfully produced with tight distribution and good sphericity. The excited jet breakup process is promising for cost effectively producing solder ball.

  17. Cosmetic effect of knee joint in a knee disarticulation prosthesis

    NARCIS (Netherlands)

    de laat, Fred A.; van der Pluijm, Mark J.; van Kuijk, Annette A.; Geertzen, Jan H.; Roorda, Leo D.

    2014-01-01

    Despite numerous advantages, knee disarticulations (KDs) are rarely performed because of the anticipated KD prosthesis fitting problems that include the positioning of the knee joint distally from the KD socket. This results in lengthening of the thigh and subsequent shortening of the shank. The obj

  18. Characterization of PVC joints' behaviour during variable loading laboratory tests

    NARCIS (Netherlands)

    Arsénio, André Marques; Vreeburg, J.H.G.; Bouma, Freddie; Rietveld, J.C.

    2015-01-01

    With the objective of defining parameters that can be used to assess the condition of PVC joints in the field, more than two-hundred destructive tests were done in the laboratory. Two diameters (110 mm and 315 mm) of new PVC double-sockets were tested. The occurrence of leakage during water press

  19. Influence of malalignment on socket reaction moments during gait in amputees with transtibial prostheses.

    Science.gov (United States)

    Boone, David A; Kobayashi, Toshiki; Chou, Teri G; Arabian, Adam K; Coleman, Kim L; Orendurff, Michael S; Zhang, Ming

    2013-04-01

    Alignment - the process and measured orientation of the prosthetic socket relative to the foot - is important for proper function of a transtibial prosthesis. Prosthetic alignment is performed by prosthetists using visual gait observation and amputees' feedback. The aim of this study was to investigate the effect of transtibial prosthesis malalignment on the moments measured at the base of the socket: the socket reaction moments. Eleven subjects with transtibial amputation were recruited from the community. An instrumented prosthesis alignment component was used to measure socket reaction moments during ambulation under 17 alignment conditions, including nominally aligned using conventional clinical methods, and angle perturbations of 3° and 6° (flexion, extension, abduction, and adduction) and translation perturbations of 5mm and 10mm (anterior, posterior, lateral, and medial) referenced from the nominal alignment. Coronal alignment perturbations caused systematic changes in the coronal socket reaction moments. All angle and translation perturbations revealed statistically significant differences on coronal socket reaction moments compared to the nominal alignment at 30% and 75% of stance phase (Psocket reaction moments was not as responsive as that of the coronal perturbations. The sagittal angle and translation perturbations of the socket led to statistically significant changes in minimum moment, maximum moment, and moments at 45% of stance phase in the sagittal plane. Therefore, malalignment affected the socket reaction moments in amputees with transtibial prostheses.

  20. Medicinal plants in the healing of dry socket in rats: microbiological and microscopic analysis.

    Science.gov (United States)

    de Melo Júnior, E J M; Raposo, M J; Lisboa Neto, J A; Diniz, M F A; Marcelino Júnior, C A C; Sant'Ana, A E G

    2002-03-01

    The effectiveness of medicinal herbs as antimicrobial agents was tested on isolated microorganisms from an induced alveolitis and on alveolitis in rats. Sixteen ethanolic extracts from plants were prepared and tested. The plant materials were selected from ethnobotanic data and the best result was obtained with Schinus terebinthifolius Raddi. The activity on Enterococcus, Bacillus corineforme, Streptococcus viridans and S. beta-hemolytic was better than the one presented by the antibiotic currently used for the treatment of alveolitis. The extract of Schinus terebinthifolius Raddi has shown good wound-healing activity by histological analysis. PMID:11995943

  1. Ball Collision Experiments

    Science.gov (United States)

    Cross, R.

    2015-01-01

    Experiments are described on collisions between two billiard balls and between a bat and a ball. The experiments are designed to extend a student's understanding of collision events and could be used either as a classroom demonstration or for a student project.

  2. Structural and magnetic properties of ball milled copper ferrite

    DEFF Research Database (Denmark)

    Goya, G.F.; Rechenberg, H.R.; Jiang, Jianzhong

    1998-01-01

    cation redistribution between A and B sites. These nanometer-sized particles show superparamagnetic relaxation effects at room temperature. It is found that the magnetization is not saturated even with an applied field of 9 T, possibly as the result of spin canting in the partially inverted CuFe2O4. The......The structural and magnetic evolution in copper ferrite (CuFe2O4) caused by high-energy ball milling are investigated by x-ray diffraction, Mössbauer spectroscopy, and magnetization measurements. Initially, the milling process reduces the average grain size of CuFe2O4 to about 6 nm and induces...... canted spin configuration is also suggested by the observed reduction in magnetization of particles in the blocked state. Upon increasing the milling time, nanometer-sized CuFe2O4 particles decompose, forming alpha-Fe2O3 and other phases, causing a further decrease of magnetization. After a milling time...

  3. Advancing description and explanation in clinical linguistics: a legacy of Martin J. Ball.

    Science.gov (United States)

    Damico, Jack S; Damico, Holly L; Nelson, Ryan L

    2011-11-01

    This article asserts the importance of explication of order and disorder in language as a privileged objective of clinical linguistics and service delivery and reviews the contributions of Martin Ball in advancing this agenda.

  4. Petrography and microanalysis of Pennsylvanian coal-ball concretions (Herrin Coal, Illinois Basin, USA): Bearing on fossil plant preservation and coal-ball origins

    Science.gov (United States)

    Siewers, Fredrick D.; Phillips, Tom L.

    2015-11-01

    Petrographic analyses of 25 coal balls from well-studied paleobotanical profiles in the Middle Pennsylvanian Herrin Coal (Westphalian D, Illinois Basin) and five select coal balls from university collections, indicate that Herrin Coal-ball peats were permineralized by fibrous and non-fibrous carbonates. Fibrous carbonates occur in fan-like to spherulitic arrays in many intracellular (within tissue) pores, and are best developed in relatively open extracellular (between plant) pore spaces. Acid etched fibrous carbonates appear white under reflected light and possess a microcrystalline texture attributable to abundant microdolomite. Scanning electron microscopy, X-ray diffraction, and electron microprobe analysis demonstrate that individual fibers have a distinct trigonal prism morphology and are notable for their magnesium content (≈ 9-15 mol% MgCO3). Non-fibrous carbonates fill intercrystalline spaces among fibers and pores within the peat as primary precipitates and neomorphic replacements. In the immediate vicinity of plant cell walls, non-fibrous carbonates cut across fibrous carbonates as a secondary, neomorphic phase attributed to coalification of plant cell walls. Dolomite occurs as diagenetic microdolomite associated with the fibrous carbonate phase, as sparite replacements, and as void-filling cement. Maximum dolomite (50-59 wt.%) is in the top-of-seam coal-ball zone at the Sahara Mine, which is overlain by the marine Anna Shale. Coal-ball formation in the Herrin Coal began with the precipitation of fibrous high magnesium calcite. The trigonal prism morphology of the carbonate fibers suggests rapid precipitation from super-saturated, meteoric pore waters. Carbonate precipitation from marine waters is discounted on the basis of stratigraphic, paleobotanical, and stable isotopic evidence. Most non-fibrous carbonate is attributable to later diagenetic events, including void-fill replacements, recrystallization, and post-depositional fracture fills. Evidence

  5. Literature review of the possible advantages of silicon liner socket use in trans-tibial prostheses

    NARCIS (Netherlands)

    Baars, ECT; Geertzen, JHB

    2005-01-01

    The silicon liner socket has been used in the trans-tibial prosthesis since the 1980s. Silicon liner sockets are sleeves of silicon material that are rolled onto the stump and fix the prosthesis to it. The producers of the liners propagate many advantages in their use i.e. better suspension of the p

  6. Borner Ball Neutron Detector

    Science.gov (United States)

    2002-01-01

    The Bonner Ball Neutron Detector measures neutron radiation. Neutrons are uncharged atomic particles that have the ability to penetrate living tissues, harming human beings in space. The Bonner Ball Neutron Detector is one of three radiation experiments during Expedition Two. The others are the Phantom Torso and Dosimetric Mapping.

  7. Revisiting the gravitino dark matter and baryon asymmetry from Q-ball decay in gauge mediation

    Energy Technology Data Exchange (ETDEWEB)

    Kasuya, Shinta, E-mail: kasuya@kanagawa-u.ac.jp [Department of Mathematics and Physics, Kanagawa University, Kanagawa 259-1293 (Japan); Max-Planck-Institut für Kernphysik, PO Box 103980, 69029 Heidelberg (Germany); Kawasaki, Masahiro [Institute for Cosmic Ray Research, the University of Tokyo, Chiba 277-8582 (Japan); Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, the University of Tokyo, Chiba 277-8582 (Japan); Yamada, Masaki [Institute for Cosmic Ray Research, the University of Tokyo, Chiba 277-8582 (Japan)

    2013-10-07

    We reconsider the Q-ball decay and reinvestigate the scenario that the amount of the baryons and the gravitino dark matter is naturally explained by the decay of the Q balls in the gauge-mediated SUSY breaking. We refine the decay rates into baryons, NLSPs, and gravitinos, and estimate their branching ratios based on the consideration of Pauli blocking. We obtain a smaller branching into gravitinos than the previous estimate, and the NLSPs are more produced by the Q-ball decay. However, the efficient annihilations of NLSPs occur afterward so that their abundance does not spoil the successful BBN and they only produce negligible amount of the gravitinos to the dark matter density by their decay. In this way, we find that the scenario with the direct production of the gravitino dark matter from the Q-ball decay works naturally.

  8. SUSY Q-balls and Boson stars in Anti-de Sitter space-time

    Energy Technology Data Exchange (ETDEWEB)

    Riedel, Juergen [School of Engineering and Science, Jacobs University Bremen (Germany)

    2012-07-01

    Q-balls and boson stars are non-topological solitons that have been intensively studied and their properties are well established for a variety of scalar potentials. More recently a supersymmetric (SUSY) potential has been considered for Q-ball and boson star models in the context of the supersymmetric extension of the Standard Model. Moreover, it has been proposed that such soliton models can be interpreted as Bose-Einstein condensates of glueballs within the context of the Anti-de Sitter/Conformal Field Theory (AdS/CFT) correspondence. We solve the Klein-Gordon equation for the SUSY Q-balls in AdS background numerically and study the solutions in detail. In particular the mass M and charge Q of the Q-balls in AdS background are calculated.

  9. Comparison of Ball-And-Racket Impact Force in Two-Handed Backhand Stroke Stances for Different-Skill-Level Tennis Players.

    Science.gov (United States)

    Lo, Kuo-Cheng; Hsieh, Yung-Chun

    2016-06-01

    This study compared the kinetic roles of the upper extremities in racket impact force generation between the open stance (OS) and square stance (SS) for tennis players with different skill levels in two-handed backhand strokes. Twelve male tennis players were divided into an advanced group (AG) (L3-L2 skill level) and intermediate group (IG) (L7-L6 skill level), and their data were used in a three-dimensional kinetic analysis. Their motions were captured using 21 reflective markers attached to anatomic landmarks for two-handed backhand stroke motion data collection. During the acceleration phase, significant differences were not observed between both stances, but they were observed between the groups with different skill levels for the force of the upper extremities (p = 0.027). The joint forces were significantly lower in the AG than in the IG. Players performing the SS had significantly larger pronation and supination of the wrist joint moment than those in the OS (p = 0.032) during the acceleration phase, irrespective of the playing level. Higher internal rotation moment after impact was observed at each joint, particularly among young intermediate tennis players, regardless of their stance. The AG demonstrated a higher joint force and moment at every joint compared with the IG at impact. Moreover, the AG demonstrated superior stroke efficiency and effectively reduced joint moment after impact and sports injury. Key pointsAdvanced players, regardless of open stance or square stance, have larger joint force and moment at each joint before ball impact resulting in better stroke efficiency and reduced chance of injury.Intermediate players, regardless of stance, have higher internal rotation moment at each joint instead of larger joint force as compared to advanced players before ball impact. The higher internal rotation moment will induce higher joint impact force which makes the player injury-prone.Young intermediate tennis players may want to avoid excessive

  10. Comparison of Ball-And-Racket Impact Force in Two-Handed Backhand Stroke Stances for Different-Skill-Level Tennis Players.

    Science.gov (United States)

    Lo, Kuo-Cheng; Hsieh, Yung-Chun

    2016-06-01

    This study compared the kinetic roles of the upper extremities in racket impact force generation between the open stance (OS) and square stance (SS) for tennis players with different skill levels in two-handed backhand strokes. Twelve male tennis players were divided into an advanced group (AG) (L3-L2 skill level) and intermediate group (IG) (L7-L6 skill level), and their data were used in a three-dimensional kinetic analysis. Their motions were captured using 21 reflective markers attached to anatomic landmarks for two-handed backhand stroke motion data collection. During the acceleration phase, significant differences were not observed between both stances, but they were observed between the groups with different skill levels for the force of the upper extremities (p = 0.027). The joint forces were significantly lower in the AG than in the IG. Players performing the SS had significantly larger pronation and supination of the wrist joint moment than those in the OS (p = 0.032) during the acceleration phase, irrespective of the playing level. Higher internal rotation moment after impact was observed at each joint, particularly among young intermediate tennis players, regardless of their stance. The AG demonstrated a higher joint force and moment at every joint compared with the IG at impact. Moreover, the AG demonstrated superior stroke efficiency and effectively reduced joint moment after impact and sports injury. Key pointsAdvanced players, regardless of open stance or square stance, have larger joint force and moment at each joint before ball impact resulting in better stroke efficiency and reduced chance of injury.Intermediate players, regardless of stance, have higher internal rotation moment at each joint instead of larger joint force as compared to advanced players before ball impact. The higher internal rotation moment will induce higher joint impact force which makes the player injury-prone.Young intermediate tennis players may want to avoid excessive

  11. 48 CFR 225.7009 - Restriction on ball and roller bearings.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Restriction on ball and roller bearings. 225.7009 Section 225.7009 Federal Acquisition Regulations System DEFENSE ACQUISITION... roller bearings....

  12. Lagrangian Dynamics of Open Multibody Systems with Generalized Holonomic and Nonholonomic Joints

    NARCIS (Netherlands)

    Duindam, Vincent; Stramigioli, Stefano

    2007-01-01

    Standard methods to model multibody systems are aimed at systems with configuration spaces isomorphic to Rn. This limitation leads to singularities and other artifacts in case the configuration space has a different topology, for example in the case of ball joints or a free-floating mechanism. This

  13. Ball Speed and Release Consistency Predict Pitching Success in Major League Baseball.

    Science.gov (United States)

    Whiteside, David; Martini, Douglas N; Zernicke, Ronald F; Goulet, Grant C

    2016-07-01

    Whiteside, D, Martini, DN, Zernicke, RF, and Goulet, GC. Ball speed and release consistency predict pitching success in Major League Baseball. J Strength Cond Res XX(X): 000-000, 2015-This study aimed to quantify how ball flight kinematics (i.e., ball speed and movement), release location, and variations therein relate to pitching success in Major League Baseball (MLB). One hundred ninety starting MLB pitchers met the inclusion criteria for this study. Ball trajectory information was collected for 76,000 pitches and inserted into a forward stepwise multiple regression model, which examined how (a) pitch selection, (b) ball speed, (c) ball movement (horizontal and lateral), (d) release location (horizontal and lateral), (e) variation in pitch speed, (f) variation in ball movement, and (g) variation in release location related to pitching success (as measured by fielding independent pitching-FIP). Pitch speed, release location variability, variation in pitch speed, and horizontal release location were significant predictors of FIP and, collectively, accounted for 24% of the variance in FIP. These findings suggest that (a) maximizing ball speed, (b) refining a consistent spatial release location, and (c) using varied pitch speeds should be primary foci for the pitching coach. However, between-pitcher variations underline how training interventions should be administered at the individual level, with consideration given to the pitcher's injury history. Finally, despite offering significant predictors of success, these three factors explained only 22% of the variance in FIP and should not be considered the only, or preeminent, indicators of a pitcher's effectiveness. Evidently, traditional pitching metrics only partly account for a pitcher's effectiveness, and future research is necessary to uncover the remaining contributors to success. PMID:26677832

  14. Invariant Mean-Value Property and M-Harmonicity in the Unit Ball of Rn

    Institute of Scientific and Technical Information of China (English)

    Cong Wen LIU; Ji Huai SHI

    2003-01-01

    In 1993, Ahern, Flores and Rudin showed that, if f is integrable over the unit ball BnC ofCn and satisfies ∫Bnc foψdv=f(ψ(0)) for every ψ∈ Aut(BnC), then f is M-harmonic if and only if n ≤ 11. The present paper is about ananalogous question in the context of the unit ball Bn of Rn as well as in the weighted setting.

  15. Auditing Pricing and Auditor Change: an Investigation of Low-balling Effect in the UK

    OpenAIRE

    Li, Ye

    2009-01-01

    Public authority, the media and academic researchers have expressed concern over the price discounting behavior followed by an initial auditor change. This audit low balling effect is significant since it is criticized as a threat to auditor independence. This study investigates the impact of auditor change in audit fees, and to determine whether the low balling behavior takes place in the UK audit market. Tests are conducted for a sample of 250 public listed companies selected from London St...

  16. Tropical Krichever construction for the non-periodic box and ball system

    CERN Document Server

    Iwao, Shinsuke; Isojima, Shin

    2012-01-01

    A solution for an initial value problem of the box and ball system is constructed from a solution of the periodic box and ball system. The construction is done through a specific limiting process based on the theory of tropical geometry. This method gives a tropical analogue of the Krichever construction, which is an algebro-geometric method to construct exact solutions to integrable systems, for the non-periodic system.

  17. Correspondence of I and Q-balls as Non-relativistic Condensates

    CERN Document Server

    Mukaida, Kyohei

    2014-01-01

    In the non-relativistic limit, a real scalar field approximately conserves its number and obeys an equation that governs a complex scalar field theory with a conserved global U(1) symmetry in the non-relativistic limit. From this fact, it is shown that the I-ball (oscillon) can be naturally understood as a projection (e.g., real part) of the non-relativistic Q-ball solution. In particular, we clarify that the stability of the I-ball is guaranteed by the U(1) symmetry in the corresponding complex scalar field theory as long as the non-relativistic condition holds. We also discuss the longevity of I-ball from the perspective of the complex scalar field in terms of U(1) charge violating processes.

  18. CAD/CAM transtibial prosthetic sockets from central fabrication facilities: How accurate are they?

    Science.gov (United States)

    Sanders, Joan E.; Rogers, Ellen L.; Sorenson, Elizabeth A.; Lee, Gregory S.; Abrahamson, Daniel C.

    2014-01-01

    This research compares transtibial prosthetic sockets made by central fabrication facilities with their corresponding American Academy of Orthotists and Prosthetists (AAOP) electronic shape files and assesses the central fabrication process. We ordered three different socket shapes from each of 10 manufacturers. Then we digitized the sockets using a very accurate custom mechanical digitizer. Results showed that quality varied considerably among the different manufacturers. Four of the companies consistently made sockets within +/−1.1% volume (approximately 1 sock ply) of the AAOP electronic shape file, while six other companies did not. Six of the companies showed consistent undersizing or oversizing in their sockets, which suggests a consistent calibration or manufacturing error. Other companies showed inconsistent sizing or shape distortion, a difficult problem that represents a most challenging limitation for central fabrication facilities. PMID:18247236

  19. A proposed model of the response of the anophthalmic socket to prosthetic eye wear and its application to the management of mucoid discharge.

    Science.gov (United States)

    Pine, Keith R; Sloan, Brian H; Jacobs, Robert J

    2013-08-01

    Mucoid discharge associated with prosthetic eye wear can be a distressing condition that affects the quality of life of people who have lost an eye. Discharge is the second highest concern of experienced prosthetic eye wearers after health of the companion eye and is prevalent in anophthalmic populations. Specific causes of mucoid discharge such as infections and environmental allergens are well understood, but non-specific causes are unknown and an evidence based protocol for managing non-specific discharge is lacking. Current management is based on prosthesis removal and cleaning, and professional re-polishing of the prosthesis. Tear protein deposits accumulate on prosthetic eyes. These deposits mediate the response of the socket to prosthetic eye wear and their influence (good and bad) is determined by differing cleaning regimes and standards of surface finish. This paper proposes a three-phase model that describes the response of the socket to prosthetic eye wear. The phases are: An initial period of wear of a new (or newly-polished) prosthesis when homeostasis is being established (or re-established) within the socket; a second period (equilibrium phase) where beneficial surface deposits have built up on the prosthesis and wear is safe and comfortable, and a third period (breakdown phase) where there is an increasing likelihood of harm from continued wear. The proposed model provides a rationale for a personal cleaning regime to manage non-specific mucoid discharge. Professional care of prosthetic eyes is also important for the management of discharge and evidence for effective surface finishing is reported in this study. Taken together, the proposed regimes for personal and professional care comprise a protocol for managing discharge associated with prosthetic eye wear. The protocol describes prosthetic eye cleaning methods and frequency, and suggests minimum standards for professional polishing. If confirmed, the protocol has the potential to resolve the

  20. Professional tennis players' serve: correlation between segmental angular momentums and ball velocity.

    Science.gov (United States)

    Martin, Caroline; Kulpa, Richard; Delamarche, Paul; Bideau, Benoit

    2013-03-01

    The purpose of the study was to identify the relationships between segmental angular momentum and ball velocity between the following events: ball toss, maximal elbow flexion (MEF), racket lowest point (RLP), maximal shoulder external rotation (MER), and ball impact (BI). Ten tennis players performed serves recorded with a real-time motion capture. Mean angular momentums of the trunk, upper arm, forearm, and the hand-racket were calculated. The anteroposterior axis angular momentum of the trunk was significantly related with ball velocity during the MEF-RLP, RLP-MER, and MER-BI phases. The strongest relationships between the transverse-axis angular momentums and ball velocity followed a proximal-to-distal timing sequence that allows the transfer of angular momentum from the trunk (MEF-RLP and RLP-MER phases) to the upper arm (RLP-MER phase), forearm (RLP-MER and MER-BI phases), and the hand-racket (MER-BI phase). Since sequence is crucial for ball velocity, players should increase angular momentums of the trunk during MEF-MER, upper arm during RLP-MER, forearm during RLP-BI, and the hand-racket during MER-BI. PMID:23724603

  1. Simultaneous Volar Dislocation of Distal Interphalangeal Joint and Volar Fracture-Subluxation of Proximal Interphalangeal Joint of Little Finger: A New Mechanism of Injury.

    Science.gov (United States)

    Mozaffarian, Kamran; Bayatpour, Abdollah; Vosoughi, Amir Reza

    2016-10-01

    Simultaneous volar dislocation of distal interphalangeal (DIP) joint and volar fracture-subluxation of proximal interphalangeal (PIP) joint of the same finger has not been reported yet. A 19-year-old man was referred due to pain on the deformed left little finger after a ball injury. Radiographs showed volar dislocation of the DIP joint and dorsal lip fracture of the middle phalanx with volar subluxation of PIP joint of the little finger. This case was unique in terms of the mechanism of injury which was hyperflexion type in two adjacent joints of the same finger. The patient was treated by closed reduction of DIP joint dislocation and open reduction and internal fixation of the PIP joint fracture-subluxation and application of dorsal external fixator due to instability. Finally, full flexion of the PIP joint and full extension of the DIP joint were obtained but with 10 degree extension lag at the PIP joint and DIP joint flexion ranging from 0 degree to 30 degrees. Some loss of motion in small joints of the fingers after hyperflexion injuries should be expected. PMID:27595966

  2. Visual monitoring of network devices based on socket and Web GIS%基于Socket及Web GIS的网络设备可视化监测

    Institute of Scientific and Technical Information of China (English)

    龚成莹; 李驰新; 权晓红

    2011-01-01

    基于Google Maps API for Flash/Flex、PHP以及Socket技术,根据网络设备的技术特点和地理分布特点,以Web GIS方式灵活地实现了网络设备在线状态检测、设备信息查询、拓扑动态监测、电子地图刷新等功能.介绍了设计思路,主要功能及实现方法.%Based on Google Maps API for Flash / Flex, PHP and Socket technology, according to the technical characterics of network devices and geographical distribution, this article implements a flexible Web GIS, achieves the situation of online network device testing, information for network device query, dynamic topology monitoring, electronic map refresh And other functions, describes the design of system, the main function and its implementation.

  3. Coordination and control of posture and ball release in basketball free-throw shooting.

    Science.gov (United States)

    Verhoeven, F Martijn; Newell, Karl M

    2016-10-01

    The objective of this study was to investigate the coordination of a whole-body task (basketball free-throw) in which success in performance outcome can be achieved through a manifold of combinations of postural and movement trajectory configurations. Participants were healthy men (19-24years) with a range of skill levels that were tested for the accuracy of 50 basketball free-throws with both their dominant and non-dominant hand. The trial-to-trial variance in release parameters as well as postural stability of the shooter and synchronization of postural movement and ball release were strong predictors of performance, with non-elite shooters having a higher mean and variability of center-of-mass (COM) speed at the time of ball release. The synchronization between the time of peak COM and the time of ball release increased as a function of skill level and hand dominance, with the better performers releasing the ball more closely to the time of COM peak height. These findings reveal how, in addition to successfully controlling the trial-to-trial variability along the solution manifold of release parameters, the relative importance of the coordination of postural control and ball release properties on shooting success changes as a function of skill level. PMID:27442763

  4. Surface-gradient cross-linked polyethylene acetabular cups: oxidation resistance and wear against smooth and rough femoral balls.

    Science.gov (United States)

    Shen, Fu-Wen; McKellop, Harry

    2005-01-01

    Two methods were developed and evaluated for cross-linking the bearing surface of a polyethylene acetabular cup to a limited depth, in order to improve its resistance to wear without degrading the mechanical properties of the bulk of the component. In the first method, low-energy electron beams were used to cross-link only the bearing surface of the cups to a maximum depth of about 2 mm. The cups then were annealed at 100 degrees C in vacuum for 3 or 6 days to reduce the residual free radicals, and the resultant resistance to oxidation was compared by artificially aging the cups at 80 degrees C in air. Chemically cross-linked surface layers were produced by coating the bearing surfaces of the cups with a thin layer of polyethylene powder mixed with 1% weight peroxide, and compressing them at 6.9 MPa (1000 psi) and 170 degrees C. This resulted in a cross-linked surface layer that extended about 3 mm deep, with a gradual transition to conventional (noncross-linked) polyethylene in the bulk of the implant. In hip simulator wear tests with highly polished (implant quality) femoral balls, both types of surface cross-linking were found to improve markedly the wear resistance of the acetabular cups. In tests with roughened femoral balls, the wear rates were much higher and were comparable to those obtained with similarly roughened balls against noncross-linked polyethylene cups in a previous study, indicating that the full benefit of cross-linking may not be realized under conditions of severe third-body abrasion. Nevertheless, these results show a promising approach for optimizing the wear resistance and the bulk mechanical properties of polyethylene components in total joint arthroplasty.

  5. TEMPOROMANDIBULAR-JOINT OSTEOARTHROSIS AND GENERALIZED JOINT HYPERMOBILITY

    NARCIS (Netherlands)

    DIJKSTRA, PU; DEBONT, LGM; STEGENGA, B; BOERING, G

    1992-01-01

    Peripheral joint mobility of temporomandibular joint (TMJ) osteoarthrosis and internal derangement patients (n = 25) and of a control group (n = 29) was measured according to a rigidly standardized protocol, in order to study the relationships between TMJ osteoarthrosis and internal derangement and

  6. Compact Q-balls

    CERN Document Server

    Bazeia, D; Marques, M A; Menezes, R; da Rocha, R

    2016-01-01

    In this work we deal with non-topological solutions of the Q-ball type in two space-time dimensions, in models described by a single complex scalar field that engenders global symmetry. The main novelty is the presence of stable Q-balls solutions that live in a compact interval of the real line and appear from a family of models controlled by two distinct parameters. We find analytical solutions and study their charge and energy, and show how to control the parameters to make the Q-balls classically and quantum mechanically stable.

  7. Acquisition and reduction of data obtained from tank 101-SY in-situ ball rheometer

    International Nuclear Information System (INIS)

    Development of the ball rheometer to measure rheological properties and density of the waste in Hanford Tank 241-SY-101 will be completed around September 1994. This instrument is expected to provide the first-of-its-kind in-situ measurements of the fluid properties of the waste contained within this tank. A mixer pump has been installed in this tank, and this pump has been very successful at mitigating the flammable gas problem associated with Tank 101-SY. The ball rheometer will serve as a diagnostic tool for judging the effectiveness of mixing in Tank 101-SY and others and will be one of few in-situ probes available for diagnostic measurements. Based on experiments performed at Los Alamos National Laboratory and Pacific Northwest Laboratory, it is believed that a generalized Bingham fluid model (Herschel-Bulkley fluid model) may be useful for describing at least some of the waste contained in Tank 101-SY, and data obtained in the tank will initially be reduced using this fluid model. The single largest uncertainty in the determination of the drag force on the ball is the drag force which will be experienced by the cable attached to the ball. This drag can be a substantial fraction of the total drag when the ball is deep within the tank. It is expected that the fluid properties may be history dependent, thus rheological properties of the undisturbed fluid may be different from the same properties after the fluid has been disturbed by passage of the ball. The data collection strategy allows the determination of the waste fluid rheology both in the undisturbed state and after it has been disturbed by the ball. Unlike the rheological parameters, measurement of density requires no model for its interpretation; however, the effects of yield stress may need to be accounted for. This measurement can be made with fairly good accuracy and may provide the most useful data in determination of mixer pump effectiveness

  8. Control design and robustness analysis of a ball and plate system by using polynomial chaos

    Science.gov (United States)

    Colón, Diego; Balthazar, José M.; dos Reis, Célia A.; Bueno, Átila M.; Diniz, Ivando S.; de S. R. F. Rosa, Suelia

    2014-12-01

    In this paper, we present a mathematical model of a ball and plate system, a control law and analyze its robustness properties by using the polynomial chaos method. The ball rolls without slipping. There is an auxiliary robot vision system that determines the bodies' positions and velocities, and is used for control purposes. The actuators are to orthogonal DC motors, that changes the plate's angles with the ground. The model is a extension of the ball and beam system and is highly nonlinear. The system is decoupled in two independent equations for coordinates x and y. Finally, the resulting nonlinear closed loop systems are analyzed by the polynomial chaos methodology, which considers that some system parameters are random variables, and generates statistical data that can be used in the robustness analysis.

  9. Control design and robustness analysis of a ball and plate system by using polynomial chaos

    Energy Technology Data Exchange (ETDEWEB)

    Colón, Diego [University of São Paulo, Polytechnic School, LAC -PTC, São Paulo (Brazil); Balthazar, José M. [São Paulo State University - Rio Claro Campus, Rio Claro (Brazil); Reis, Célia A. dos [São Paulo State University - Bauru Campus, Bauru (Brazil); Bueno, Átila M.; Diniz, Ivando S. [São Paulo State University - Sorocaba Campus, Sorocaba (Brazil); Rosa, Suelia de S. R. F. [University of Brasilia, Brasilia (Brazil)

    2014-12-10

    In this paper, we present a mathematical model of a ball and plate system, a control law and analyze its robustness properties by using the polynomial chaos method. The ball rolls without slipping. There is an auxiliary robot vision system that determines the bodies' positions and velocities, and is used for control purposes. The actuators are to orthogonal DC motors, that changes the plate's angles with the ground. The model is a extension of the ball and beam system and is highly nonlinear. The system is decoupled in two independent equations for coordinates x and y. Finally, the resulting nonlinear closed loop systems are analyzed by the polynomial chaos methodology, which considers that some system parameters are random variables, and generates statistical data that can be used in the robustness analysis.

  10. Techniques for Interface Stress Measurements within Prosthetic Sockets of Transtibial Amputees: A Review of the Past 50 Years of Research.

    Science.gov (United States)

    Al-Fakih, Ebrahim A; Abu Osman, Noor Azuan; Mahmad Adikan, Faisal Rafiq

    2016-01-01

    The distribution of interface stresses between the residual limb and prosthetic socket of a transtibial amputee has been considered as a direct indicator of the socket quality fit and comfort. Therefore, researchers have been very interested in quantifying these interface stresses in order to evaluate the extent of any potential damage caused by the socket to the residual limb tissues. During the past 50 years a variety of measurement techniques have been employed in an effort to identify sites of excessive stresses which may lead to skin breakdown, compare stress distributions in various socket designs, and evaluate interface cushioning and suspension systems, among others. The outcomes of such measurement techniques have contributed to improving the design and fitting of transtibial sockets. This article aims to review the operating principles, advantages, and disadvantages of conventional and emerging techniques used for interface stress measurements inside transtibial sockets. It also reviews and discusses the evolution of different socket concepts and interface stress investigations conducted in the past five decades, providing valuable insights into the latest trends in socket designs and the crucial considerations for effective stress measurement tools that lead to a functional prosthetic socket. PMID:27447646

  11. Techniques for Interface Stress Measurements within Prosthetic Sockets of Transtibial Amputees: A Review of the Past 50 Years of Research.

    Science.gov (United States)

    Al-Fakih, Ebrahim A; Abu Osman, Noor Azuan; Mahmad Adikan, Faisal Rafiq

    2016-07-20

    The distribution of interface stresses between the residual limb and prosthetic socket of a transtibial amputee has been considered as a direct indicator of the socket quality fit and comfort. Therefore, researchers have been very interested in quantifying these interface stresses in order to evaluate the extent of any potential damage caused by the socket to the residual limb tissues. During the past 50 years a variety of measurement techniques have been employed in an effort to identify sites of excessive stresses which may lead to skin breakdown, compare stress distributions in various socket designs, and evaluate interface cushioning and suspension systems, among others. The outcomes of such measurement techniques have contributed to improving the design and fitting of transtibial sockets. This article aims to review the operating principles, advantages, and disadvantages of conventional and emerging techniques used for interface stress measurements inside transtibial sockets. It also reviews and discusses the evolution of different socket concepts and interface stress investigations conducted in the past five decades, providing valuable insights into the latest trends in socket designs and the crucial considerations for effective stress measurement tools that lead to a functional prosthetic socket.

  12. Techniques for Interface Stress Measurements within Prosthetic Sockets of Transtibial Amputees: A Review of the Past 50 Years of Research

    Directory of Open Access Journals (Sweden)

    Ebrahim A. Al-Fakih

    2016-07-01

    Full Text Available The distribution of interface stresses between the residual limb and prosthetic socket of a transtibial amputee has been considered as a direct indicator of the socket quality fit and comfort. Therefore, researchers have been very interested in quantifying these interface stresses in order to evaluate the extent of any potential damage caused by the socket to the residual limb tissues. During the past 50 years a variety of measurement techniques have been employed in an effort to identify sites of excessive stresses which may lead to skin breakdown, compare stress distributions in various socket designs, and evaluate interface cushioning and suspension systems, among others. The outcomes of such measurement techniques have contributed to improving the design and fitting of transtibial sockets. This article aims to review the operating principles, advantages, and disadvantages of conventional and emerging techniques used for interface stress measurements inside transtibial sockets. It also reviews and discusses the evolution of different socket concepts and interface stress investigations conducted in the past five decades, providing valuable insights into the latest trends in socket designs and the crucial considerations for effective stress measurement tools that lead to a functional prosthetic socket.

  13. Vibrotactile evaluation: osseointegrated versus socket-suspended transfemoral prostheses.

    Science.gov (United States)

    Häggström, Eva; Hagberg, Kerstin; Rydevik, Björn; Brånemark, Rickard

    2013-01-01

    This study investigated detection thresholds of vibrometric stimuli in patients with transfemoral amputation supplied with osseointegrated (OI) and socket-suspended prostheses. It included 17 patients tested preoperatively with socket-suspended prostheses and after 2 yr with OI prostheses and a control group (n = 17) using socket-suspended prostheses, evaluated once. Assessments on the prosthetic and intact feet were conducted at six frequencies (8, 16, 32, 64, 125, and 250 Hz). Furthermore, measurements were conducted to investigate how vibrometric signals are transmitted through a test prosthesis. The results showed that the OI group had improved ability to detect vibrations through the prosthesis at 125 Hz (p = 0.01) at follow-up compared with the preoperative measurement. Compared with the control group, the OI group at follow-up had better ability to detect high frequency vibrations through the prosthesis (125 Hz, p = 0.02; 250 Hz, p = 0.03). The vibrometric signal transmitted through the test prosthesis was reduced at 8, 125, and 250 Hz but was amplified at 16, 32, and 64 Hz. Differences between the OI and the control groups were found in the highest frequencies in which the test prosthesis showed reduction of the vibrometric signal. The study provides insight into the mechanisms of vibration transmission between the exterior and bone-anchored as well as socket-suspended amputation prostheses.

  14. Vibrotactile evaluation: Osseointegrated versus socket-suspended transfemoral prostheses

    Directory of Open Access Journals (Sweden)

    Eva Häggström, CPO

    2014-02-01

    Full Text Available This study investigated detection thresholds of vibrometric stimuli in patients with transfemoral amputation supplied with osseointegrated (OI and socket-suspended prostheses. It included 17 patients tested preoperatively with socket-suspended prostheses and after 2 yr with OI prostheses and a control group (n = 17 using socket-suspended prostheses, evaluated once. Assessments on the prosthetic and intact feet were conducted at six frequencies (8, 16, 32, 64, 125, and 250 Hz. Furthermore, measurements were conducted to investigate how vibrometric signals are transmitted through a test prosthesis. The results showed that the OI group had improved ability to detect vibrations through the prosthesis at 125 Hz (p = 0.01 at follow-up compared with the preoperative measurement. Compared with the control group, the OI group at follow-up had better ability to detect high frequency vibrations through the prosthesis (125 Hz, p = 0.02; 250 Hz, p = 0.03. The vibrometric signal transmitted through the test prosthesis was reduced at 8, 125, and 250 Hz but was amplified at 16, 32, and 64 Hz. Differences between the OI and the control groups were found in the highest frequencies in which the test prosthesis showed reduction of the vibrometric signal. The study provides insight into the mechanisms of vibration transmission between the exterior and bone-anchored as well as socket-suspended amputation prostheses.

  15. Galvanic Interaction between Chalcopyrite and Pyrite with Low Alloy and High Carbon Chromium Steel Ball

    Directory of Open Access Journals (Sweden)

    Asghar Azizi

    2013-01-01

    Full Text Available This study was aimed to investigate the galvanic interaction between pyrite and chalcopyrite with two types of grinding media (low alloy and high carbon chromium steel ball in grinding of a porphyry copper sulphide ore. Results indicated that injection of different gases into mill altered the oxidation-reduction environment during grinding. High carbon chromium steel ball under nitrogen gas has the lowest galvanic current, and low alloy steel ball under oxygen gas had the highest galvanic current. Also, results showed that the media is anodic relative to pyrite and chalcopyrite, and therefore pyrite or chalcopyrite with a higher rest potential acted as the cathode, whilst the grinding media with a lower rest potential acted as the anode, when they are electrochemically contacted. It was also found that low alloy steel under oxygen produced the highest amount of EDTA extractable iron in the slurry, whilst high carbon chromium steel under nitrogen atmosphere led to the lowest amount.

  16. Effect of Modifying Prosthetic Socket Base Materials by Adding Nanodiamonds

    Directory of Open Access Journals (Sweden)

    Lifang Ma

    2015-01-01

    Full Text Available The curing process of prosthetic socket base materials requires attention owing to a series of associated problems that are yet to be addressed and solved. However, to date, few relevant studies have been reported. In this paper, nanodiamonds modified with a silane coupling agent were dispersed into a prosthetic socket base material, and the performance of the modified base materials was investigated. Adding a predetermined amount of nanodiamonds to the prosthetic socket base material increased the glass transition temperature, improved the mechanical properties of the cured base material, and reduced the influence of the volatile gas formed during the curing process on the environment. With increasing nanodiamond contents, the glass transition temperature increased and the mechanical properties improved slightly. Owing to the high thermal conductivity of the nanodiamonds, the localized heat, as a result of the curing process, could be dissipated and released. Thus, adding nanodiamonds led to a more uniform temperature field forming in the curing system. This improved the curing process and reduced the formation of volatile monomers, thereby decreasing the adverse impact of the generated volatile gases on the environment. All of these provide a potential strategy for modifying prosthetic socket base materials.

  17. Q-ball scattering on barriers and holes in one and two spatial dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Al-Alawi, Jassem H; Zakrzewski, Wojtek J [Department of Mathematical Sciences, University of Durham, Durham DH1 3LE (United Kingdom)], E-mail: J.H.Al-Alawi@durham.ac.uk, E-mail: W.J.Zakrzewski@durham.ac.uk

    2009-06-19

    We discuss various scattering properties of non-topological solitons, Q-balls, on potential obstructions in (1 + 1) and (2 + 1) dimensions. These obstructions, barriers and holes, are inserted into the potential of the theory via the coupling parameter, i.e. {lambda}-tilde, that is effective only in a certain region of space. When {lambda}-tilde>1 the obstruction is a barrier and when 0<{lambda}-tilde<1 the obstruction is a hole. The dynamics of Q-balls on such obstructions in (1 + 1) dimensions is shown to be very similar to that of topological solitons provided that the Q-balls are stable. In (2 + 1) dimensions, numerical simulations have shown some differences from the dynamics of topological solitons. We discuss these differences in some detail.

  18. Q-ball Scattering on Barriers and Holes in 1 and 2 Spatial Dimensions

    CERN Document Server

    Al-Alawi, Jassem H

    2009-01-01

    We discuss various scattering properties of non-topological solitons, Q-balls, on potential obstructions in (1+1) and (2+1) dimensions. These obstructions, barriers and holes, are inserted into the potential of the theory via the coupling parameter, ie \\tilde\\lambda, that is effective only in a certain region of space. When \\tilde\\lambda > 1 the obstruction is a barrier and when 0 < \\tilde\\lambda < 1 the obstruction is a hole. The dynamics of Q-balls on such obstructions in (1+1) dimensions is shown to be very similar to that of topological solitons provided that the Q-balls are stable. In (2+1) dimensions, numerical simulations have shown some differences from the dynamics of topological solitons. We discuss these differences in some detail.

  19. Q-ball scattering on barriers and holes in one and two spatial dimensions

    International Nuclear Information System (INIS)

    We discuss various scattering properties of non-topological solitons, Q-balls, on potential obstructions in (1 + 1) and (2 + 1) dimensions. These obstructions, barriers and holes, are inserted into the potential of the theory via the coupling parameter, i.e. λ-tilde, that is effective only in a certain region of space. When λ-tilde>1 the obstruction is a barrier and when 0<λ-tilde<1 the obstruction is a hole. The dynamics of Q-balls on such obstructions in (1 + 1) dimensions is shown to be very similar to that of topological solitons provided that the Q-balls are stable. In (2 + 1) dimensions, numerical simulations have shown some differences from the dynamics of topological solitons. We discuss these differences in some detail

  20. Effect of Kinesiotape Applications on Ball Velocity and Accuracy in Amateur Soccer and Handball

    Directory of Open Access Journals (Sweden)

    Müller Carsten

    2015-12-01

    Full Text Available Evidence supporting performance enhancing effects of kinesiotape in sports is missing. The aims of this study were to evaluate effects of kinesiotape applications with regard to shooting and throwing performance in 26 amateur soccer and 32 handball players, and to further investigate if these effects were influenced by the players’ level of performance. Ball speed as the primary outcome and accuracy of soccer kicks and handball throws were analyzed with and without kinesiotape by means of radar units and video recordings. The application of kinesiotapes significantly increased ball speed in soccer by 1.4 km/h (p=0.047 and accuracy with a lesser distance from the target by -6.9 cm (p=0.039. Ball velocity in handball throws also significantly increased by 1.2 km/h (p=0.013, while accuracy was deteriorated with a greater distance from the target by 3.4 cm (p=0.005. Larger effects with respect to ball speed were found in players with a lower performance level in kicking (1.7 km/h, p=0.028 and throwing (1.8 km/h, p=0.001 compared with higher level soccer and handball players (1.2 km/h, p=0.346 and 0.5 km/h, p=0.511, respectively. In conclusion, the applications of kinesiotape used in this study might have beneficial effects on performance in amateur soccer, but the gain in ball speed in handball is counteracted by a significant deterioration of accuracy. Subgroup analyses indicate that kinesiotape may yield larger effects on ball velocity in athletes with lower kicking and throwing skills.

  1. Effect of Kinesiotape Applications on Ball Velocity and Accuracy in Amateur Soccer and Handball.

    Science.gov (United States)

    Müller, Carsten; Brandes, Mirko

    2015-12-22

    Evidence supporting performance enhancing effects of kinesiotape in sports is missing. The aims of this study were to evaluate effects of kinesiotape applications with regard to shooting and throwing performance in 26 amateur soccer and 32 handball players, and to further investigate if these effects were influenced by the players' level of performance. Ball speed as the primary outcome and accuracy of soccer kicks and handball throws were analyzed with and without kinesiotape by means of radar units and video recordings. The application of kinesiotapes significantly increased ball speed in soccer by 1.4 km/h (p=0.047) and accuracy with a lesser distance from the target by -6.9 cm (p=0.039). Ball velocity in handball throws also significantly increased by 1.2 km/h (p=0.013), while accuracy was deteriorated with a greater distance from the target by 3.4 cm (p=0.005). Larger effects with respect to ball speed were found in players with a lower performance level in kicking (1.7 km/h, p=0.028) and throwing (1.8 km/h, p=0.001) compared with higher level soccer and handball players (1.2 km/h, p=0.346 and 0.5 km/h, p=0.511, respectively). In conclusion, the applications of kinesiotape used in this study might have beneficial effects on performance in amateur soccer, but the gain in ball speed in handball is counteracted by a significant deterioration of accuracy. Subgroup analyses indicate that kinesiotape may yield larger effects on ball velocity in athletes with lower kicking and throwing skills. PMID:26839612

  2. Leo de Ball and his contributions to international astronomical projects around 1900. (German Title: Leo de Ball und seine Beiträge zu internationalen Astronomieprojekten um 1900)

    Science.gov (United States)

    Habison, Peter

    From 1891 until 1916 Leo de Ball was the director of the Kuffner Observatory in Vienna. Born in Germany in 1853, he studied at Berlin and Bonn. After having received his doctorate in 1877, he became assistant at Gotha. From 1881 to 1882 he worked at the observatory in Bothkamp, where he discovered the minor planet ``Athamantis''. In 1883, he followed an invitation to the Ougrée Observatory in Belgium. Here he published some quite remarkable papers on the mass of Saturn and was also introduced to meridian circle astronomy. In 1891 he received a call to Moriz von Kuffner's observatory in Vienna. During that time the Astronomische Gesellschaft called for an extension of the ``Zonenunternehmen'' to southern declinations from -2 ° to -23°. De Ball took over the zone -5°50´ to -10°50´. This work occupied most of his time from 1892 to 1896. In 1900 Leo de Ball initiated a project for determining relative parallaxes of 252 stars in collaboration with four observatories. Although the project was only partly executed, Leo de Ball published relative parallaxes of 16 stars, observed from 1901 to 1907 with the Vienna heliometer.

  3. Effect of ball milling materials and methods on powder processing of Bi2223 superconductors

    Science.gov (United States)

    Yavuz, M.; Maeda, H.; Vance, L.; Liu, H. K.; Dou, S. X.

    1998-10-01

    Various milling systems consisting of agate and polypropylene grinding containers, agate and YSZ balls, and dry and wet milling were used in planetary ball-milling and YSZ balls and YSZ container were used in wet and dry attrition milling. The differently milled powders were then evaluated by measurements of particle size, surface area, porosity, size distribution and chemical analysis of the Si, Zr and C contents. The results show that dry milling is much more efficient for particle size reduction in planetary milling than wet milling, whereas wet milling and dry milling gave quite similar results in attrition milling. Meanwhile 0953-2048/11/10/056/img6 contamination was found in powder milled with an agate container with agate balls. Some C contamination from the polypropylene container was detected after milling, but negligible Zr from YSZ balls and C from the grinding carrier (hexane). It was found that after 1 h milling in the planetary mill fracture mechanisms transform from the elastic to the plastic region. Therefore, further milling is not very effective. It was also shown that the Bi2212 phase decomposes into several non-superconducting oxides such as 0953-2048/11/10/056/img7, CuO and a main amorphous phase after extensive dry milling.

  4. Joint Performance and Planning System

    Data.gov (United States)

    US Agency for International Development — A joint State/USAID system hosted by State that integrates resource and performance information at the program level and enables more flexible and frequent entry of...

  5. Systematic review of effects of current transtibial prosthetic socket designs—Part 2: Quantitative outcomes

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Safari, PhD

    2016-09-01

    Full Text Available This review is an attempt to untangle the complexity of transtibial prosthetic socket fit and perhaps find some indication of whether a particular prosthetic socket type might be best for a given situation. In addition, we identified knowledge gaps, thus providing direction for possible future research. We followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, using medical subject headings and standard key words to search for articles in relevant databases. No restrictions were made on study design and type of outcome measure used. From the obtained search results (n = 1,863, 35 articles were included. The relevant data were entered into a predefined data form that included the Downs and Black risk of bias assessment checklist. This article presents the results from the systematic review of the quantitative outcomes (n = 27 articles. Trends indicate that vacuum-assisted suction sockets improve gait symmetry, volume control, and residual limb health more than other socket designs. Hydrostatic sockets seem to create less inconsistent socket fittings, reducing a problem that greatly influences outcome measures. Knowledge gaps exist in the understanding of clinically meaningful changes in socket fit and its effect on biomechanical outcomes. Further, safe and comfortable pressure thresholds under various conditions should be determined through a systematic approach.

  6. Systematic review of effects of current transtibial prosthetic socket designs--Part 2: Quantitative outcomes.

    Science.gov (United States)

    Safari, Mohammad Reza; Meier, Margrit Regula

    2015-01-01

    This review is an attempt to untangle the complexity of transtibial prosthetic socket fit and perhaps find some indication of whether a particular prosthetic socket type might be best for a given situation. In addition, we identified knowledge gaps, thus providing direction for possible future research. We followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, using medical subject headings and standard key words to search for articles in relevant databases. No restrictions were made on study design and type of outcome measure used. From the obtained search results (n = 1,863), 35 articles were included. The relevant data were entered into a predefined data form that included the Downs and Black risk of bias assessment checklist. This article presents the results from the systematic review of the quantitative outcomes (n = 27 articles). Trends indicate that vacuum-assisted suction sockets improve gait symmetry, volume control, and residual limb health more than other socket designs. Hydrostatic sockets seem to create less inconsistent socket fittings, reducing a problem that greatly influences outcome measures. Knowledge gaps exist in the understanding of clinically meaningful changes in socket fit and its effect on biomechanical outcomes. Further, safe and comfortable pressure thresholds under various conditions should be determined through a systematic approach.

  7. Effects of the Horse Riding Simulator and Ball Exercises on Balance of the Elderly

    Science.gov (United States)

    Kim, SeongGil; Yuk, Goon-chang; Gak, Hwangbo

    2013-01-01

    [Purpose] The aim of this study was to examine the effects of horse riding exercise using a horse riding simulator (HRS) and a ball on static and dynamic balance of elderly people. [Methods] Thirty-two elderly people hospitalized in geriatric hospitals were randomly assigned to the HRS exercise group or the ball exercise groups, and they performed exercise for eight weeks. [Results] The length of postural sway during quite standing with and without eyes closed significantly decreased in both groups after the exercises and there was no significant difference between both groups in the Romberg test. In the functional reach test (FRT), there were significant increases in distance in both groups after the exercises, and the distance of the HRS exercise group was significantly greater than that of the ball exercise group. In the Timed Up & Go test (TUG) and Timed 10-meter walk test (10MWT), the time significantly decreased in both groups, and there was a more significant decrease in the HRS exercise group than in the ball exercise group. [Conclusion] The results of this study indicate that HRS and ball exercises may improve the balance and gait ability of elderly people hospitalized in nursing homes or geriatric hospitals. PMID:24396203

  8. Ball Possession Effectiveness in Men's Elite Floorball According to Quality of Opposition and Game Period.

    Science.gov (United States)

    Gómez, Miguel-Ángel; Prieto, Miguel; Pérez, Javier; Sampaio, Jaime

    2013-01-01

    The aim of the present study was to identify the importance of floorball tactical variables to predict ball possession effectiveness, when controlling quality of opposition and game periods. The sample was composed by 1500 ball possessions, corresponding to 14 games randomly selected from the International Championships played during 2008 and 2010 (World Championship, Four nations tournament and classificatory phases for World Championship) by teams from different competition levels (HIGH, INTERMEDIATE and LOW). The effects of the predictor variables on successful ball possessions according to the three game contexts (HIGH vs. HIGH; HIGH vs. LOW; LOW vs. LOW games) were analyzed using Binomial Logistic Regressions. The results showed no interaction with the game period. In HIGH vs. HIGH games, quality of opposition showed an association with ball possession effectiveness with ending zone, offensive system, possession duration, height of shooting and defensive pressures previous to the shot. In HIGH vs. LOW games the important factors were the starting zone, possession duration, defensive pressure previous to the last pass and to the shot, technique of shooting and the number players involved in each ball possession. Finally, in LOW vs. LOW games, the results emphasized the importance of starting and ending zones, the number of passes used and the technique of shooting. In conclusion, elite floorball performance is mainly affected by quality of opposition showing different game patterns in each context that should be considered by coaches when preparing practices and competitions.

  9. Q-ball Scattering on Barriers and Holes in 1 and 2 Spatial Dimensions

    OpenAIRE

    Al-Alawi, Jassem H.; Zakrzewski, Wojtek J.

    2009-01-01

    We discuss various scattering properties of non-topological solitons, Q-balls, on potential obstructions in (1+1) and (2+1) dimensions. These obstructions, barriers and holes, are inserted into the potential of the theory via the coupling parameter, ie \\tilde\\lambda, that is effective only in a certain region of space. When \\tilde\\lambda > 1 the obstruction is a barrier and when 0 < \\tilde\\lambda < 1 the obstruction is a hole. The dynamics of Q-balls on such obstructions in (1+1) dimensions i...

  10. The Contents of Ustiloxins A and B along with Their Distribution in Rice False Smut Balls.

    Science.gov (United States)

    Wang, Xiaohan; Fu, Xiaoxiang; Lin, Fengke; Sun, Weibo; Meng, Jiajia; Wang, Ali; Lai, Daowan; Zhou, Ligang; Liu, Yang

    2016-01-01

    Ustiloxins are cyclopeptide mycotoxins isolated from rice false smut balls (FSBs), the ball-like colonies transformed from the individual grains through the filament infection by the fungal pathogen Villosiclava virens. There were no obvious relations between ustiloxin content and any of the collection areas, collection times, or average weight of each FSB. The rice false smut balls at early, middle, and late maturity stages were respectively divided into different parts (glume, chlamydospores, mycelia, and pseudoparenchyma). The highest content of ustiloxins A and B of rice FSBs was found at the early maturity stage. Both ustiloxins A and B were mainly distributed in the middle layer containing mycelia and immature chlamydospores of the FSBs. When the rice FSBs were at the early maturity stage, the total yield of ustiloxins A and B in the middle layer of each ball was 48.3 µg, which was 3.20-fold of the yield (15.1 µg) of the inner part of the ball. The rice FSBs at the early maturity stage are the appropriate materials for the production of ustiloxins A and B. PMID:27608042

  11. Passing Success Percentages and Ball Possession Rates of Successful Teams in 2014 FIFA World Cup

    Directory of Open Access Journals (Sweden)

    Kemal GÖRAL

    2015-03-01

    Full Text Available This study was conducted to examine the ball possession and passing success percentage of successful teams in 2014 FIFA World Cup. The data were obtained from international TV channels publishing competitions and the database of the website of the Fédération Internationale de Football Association - FIFA through official overviews of the games. So the parameters such as ball possession percentages, passing attempted, passing success percentages, accurate and non-accurate passes of successful teams in matches were analyzed. These performance indicators were analyzed by e-Analyze Soccer computer program. The data obtained in this study was recorded in SPSS 16.0 program and interpreted by calculating frequency and percentage values. Ball possession percentages of the successful teams vary between 50.32% and 56.71%. Among 17102 passing attempts of successful teams, it was determined that 133378 were successful having a high rate of passing success such as 78.22%. As a result, in the organizations such as World Cup which elite athletes participated, while successful teams had high rates of the ball possession it can be said that having the ball in midfield and offensive region and passing attempt, successful passing scores, passing success percent at a high level are the most basic principles that bring success.

  12. Real-time MR diffusion tensor and Q-ball imaging using Kalman filtering

    International Nuclear Information System (INIS)

    Diffusion magnetic resonance imaging (dMRI) has become an established research tool for the investigation of tissue structure and orientation. In this paper, we present a method for real-time processing of diffusion tensor and Q-ball imaging. The basic idea is to use Kalman filtering framework to fit either the linear tensor or Q-ball model. Because the Kalman filter is designed to be an incremental algorithm, it naturally enables updating the model estimate after the acquisition of any new diffusion-weighted volume. Processing diffusion models and maps during ongoing scans provides a new useful tool for clinicians, especially when it is not possible to predict how long a subject may remain still in the magnet. First, we introduce the general linear models corresponding to the two diffusion tensor and analytical Q-ball models of interest. Then, we present the Kalman filtering framework and we focus on the optimization of the diffusion orientation sets in order to speed up the convergence of the online processing. Last, we give some results on a healthy volunteer for the online tensor and the Q-ball model, and we make some comparisons with the conventional offline techniques used in the literature. We could achieve full real-time for diffusion tensor imaging and deferred time for Q-ball imaging, using a single workstation. (authors)

  13. The Contents of Ustiloxins A and B along with Their Distribution in Rice False Smut Balls

    Science.gov (United States)

    Wang, Xiaohan; Fu, Xiaoxiang; Lin, Fengke; Sun, Weibo; Meng, Jiajia; Wang, Ali; Lai, Daowan; Zhou, Ligang; Liu, Yang

    2016-01-01

    Ustiloxins are cyclopeptide mycotoxins isolated from rice false smut balls (FSBs), the ball-like colonies transformed from the individual grains through the filament infection by the fungal pathogen Villosiclava virens. There were no obvious relations between ustiloxin content and any of the collection areas, collection times, or average weight of each FSB. The rice false smut balls at early, middle, and late maturity stages were respectively divided into different parts (glume, chlamydospores, mycelia, and pseudoparenchyma). The highest content of ustiloxins A and B of rice FSBs was found at the early maturity stage. Both ustiloxins A and B were mainly distributed in the middle layer containing mycelia and immature chlamydospores of the FSBs. When the rice FSBs were at the early maturity stage, the total yield of ustiloxins A and B in the middle layer of each ball was 48.3 µg, which was 3.20-fold of the yield (15.1 µg) of the inner part of the ball. The rice FSBs at the early maturity stage are the appropriate materials for the production of ustiloxins A and B. PMID:27608042

  14. Scientific validation of two commercial pressure sensor systems for prosthetic socket fit.

    Science.gov (United States)

    Polliack, A A; Sieh, R C; Craig, D D; Landsberger, S; McNeil, D R; Ayyappa, E

    2000-04-01

    The concept of measuring pressure at the interface between the stump and the prosthetic socket could provide valuable information in the process of prosthetic socket fabrication, modification, and fit. Two systems, the Rincoe Socket Fitting System (SFS) and Tekscan's F-Socket Pressure Measurement System, have been commercially designed for in situ interface pressure measurement over the past decade. Their use is not common in prosthetic practice, perhaps due to questions of cost effectiveness and the difficulties of interpreting the data. Another concern is the use of sensors for pressure measurements in areas of high contour and complex geometries such as the stump. Before these systems can be used in a clinical setting, it is necessary to determine the reliability and accuracy of each system. In order to assess the clinical validity of the Rincoe SFS and F-Socket systems, a series of trials was conducted to evaluate different aspects of sensor performance, namely; accuracy, hysteresis, drift and the effect of curvature. The sensors were subjected to tests in flatbed and custom-designed pressure vessels. Overall results indicated an accuracy error for the Rincoe SFS system of 25% (flatbed) and 33% (mould), with a corresponding 15% (flatbed) and 23% (mould) error in hysteresis, and 7% (flatbed) and 11% (mould) drift errors. The F-Socket system demonstrated an 8% (flatbed) and 11% (mould) accuracy errors, 42% (flatbed) and 24% (mould) hysteresis errors, and 12% (flatbed) and 33% (mould) drift errors. These findings indicate favourable results for the F-Socket Pressure Measurement System compared to the Rincoe Socket Fitting System with respect to its accuracy errors only. Nevertheless, it is the authors' belief that these systems are adequate in indicating areas of high pressure at the stump socket interface for clinical purposes, but both systems should be used with caution.

  15. Self-dispersed crumpled graphene balls in oil for friction and wear reduction.

    Science.gov (United States)

    Dou, Xuan; Koltonow, Andrew R; He, Xingliang; Jang, Hee Dong; Wang, Qian; Chung, Yip-Wah; Huang, Jiaxing

    2016-02-01

    Ultrafine particles are often used as lubricant additives because they are capable of entering tribological contacts to reduce friction and protect surfaces from wear. They tend to be more stable than molecular additives under high thermal and mechanical stresses during rubbing. It is highly desirable for these particles to remain well dispersed in oil without relying on molecular ligands. Borrowing from the analogy that pieces of paper that are crumpled do not readily stick to each other (unlike flat sheets), we expect that ultrafine particles resembling miniaturized crumpled paper balls should self-disperse in oil and could act like nanoscale ball bearings to reduce friction and wear. Here we report the use of crumpled graphene balls as a high-performance additive that can significantly improve the lubrication properties of polyalphaolefin base oil. The tribological performance of crumpled graphene balls is only weakly dependent on their concentration in oil and readily exceeds that of other carbon additives such as graphite, reduced graphene oxide, and carbon black. Notably, polyalphaolefin base oil with only 0.01-0.1 wt % of crumpled graphene balls outperforms a fully formulated commercial lubricant in terms of friction and wear reduction. PMID:26811466

  16. Air flow patterns and noise analysis inside high speed angular contact ball bearings

    Institute of Scientific and Technical Information of China (English)

    翟强; 闫柯; 张优云; 朱永生; 王亚泰

    2015-01-01

    The vortex formed around the rolling ball and the high pressure region formed around the ball−raceway contact zone are the principle factors that barricades the lubricant entering the bearing cavity, and further causes improper lubrication. The investigation of the air phase flow inside the bearing cavity is essential for the optimization of the oil−air two-phase lubrication method. With the revolutionary reference frame describing the bearing motion, a highly precise air phase flow model inside the angular contact ball bearing cavity was build up. Comprehensive factors such as bearing revolution, ball rotation, and cage structure were considered to investigate the influences on the air phase flow and heat transfer efficiency. The aerodynamic noise was also analyzed. The result shows that the ball spinning leads to the pressure rise and uneven pressure distribution. The air phase velocity, pressure and cage heat transfer efficiency increase as the revolving speed increases. The operating noise is largely due to the impact of the high speed external flow on the bearing. When the center of the oil−air outlet fixes near the inner ring, the aerodynamic noise is reduced. The position near the inner ring on the bigger axial side is the ideal position to fix the lubricating device for the angular contact ball bearing.

  17. Flame balls in non-uniform mixtures: existence and finite activation energy effects

    Science.gov (United States)

    Daou, Remi; Pearce, Philip; Daou, Joel

    2016-01-01

    The paper's broad motivation, shared by a recent theoretical investigation [Daou and Daou, "Flame balls in mixing layers," Combustion and Flame, Vol. 161 (2014), pp. 2015-2024], is a fundamental but apparently untouched combustion question; specifically, 'What are the critical conditions insuring the successful ignition of a diffusion flame by means of an external energy deposit (spark), after mixing of cold reactants has occurred in a mixing layer?' The approach is based on a generalisation of the concept of Zeldovich flame balls, well known in premixed reactive mixtures, to non-uniform mixtures. This generalisation leads to a free boundary problem (FBP) for axisymmetric flame balls in a two-dimensional mixing layer in the distinguished limit β → ∞ with εL = O(1); here β is the Zeldovich number and εL is a non-dimensional measure of the stoichiometric premixed flame thickness. The existence of such flame balls is the main object of current investigation. Several original contributions are presented. First, an analytical contribution is made by carrying out the analysis of Daou and Daou (2014) in the asymptotic limit εL → 0 to higher order. The results capture, in particular, the dependence of the location of the flame ball centre (argued to represent the optimal ignition location which differs from the stoichiometric location) on εL. Second, two detailed numerical studies of the axisymmetric flame balls are presented for arbitrary values of εL. The first study addresses the infinite-β FBP and the second one the original finite-β problem based on the constant density reaction-diffusion equations. In particular, it is shown that solutions to the FBP exist for arbitrary values of εL while actual finite-β flame balls exist in a specific domain of the β-εL plane, namely for εL less than a maximum value proportional to ?; this scaling is consistent with the existence of solutions to the FBP for arbitrary εL. In fact, the flame ball existence domain

  18. Preparation and Characterization of Stainless Steel/TiC Nanocomposite Particles by Ball-milling Method

    Institute of Scientific and Technical Information of China (English)

    CHEN Wenyi; ZHOU Jian

    2009-01-01

    A stainless steel/10wt%TiC nanocomposite particles were prepared by high-energy ball-milling method using stainless steel, carbon and titanium as raw materials. The evolution of phase composition, microstructure and specific surface area of the stainless steel/TiC nanocomposite particles with increasing ball-milling time in the range of 0-100 h were investigated by XRD, SEM, TEM and BET techniques. The results showed that the stainless steel/TiC nano-composite particles were fabricated when the ball-milling time was longer than 20 h. However, the nanocomposite particles were soldered and agglomerated again when the ball-milling time was longer than 60 h. The microstructure of the composite particles transformed from lamellar structure to nanostructure during the repeated process of the cold welding and cracking. TEM image reveals clearly that the in-situ TiC nanoparticles with grain size of 3-8 nm are in the interior of the stainless steel/TiC nanocomposite particles obtained by ball-milling 100 h.

  19. RadBall{sup TM} Technology Testing and MCNP Modeling of the Tungsten Collimator

    Energy Technology Data Exchange (ETDEWEB)

    Farfan, Eduardo B; Foley, Trevor Q; Coleman, J Rusty; Jannik, G Timothy; Holmes, Christopher J; Oldham, Mark; Adamovics, John; Stanley, Steven J, E-mail: Eduardo.Farfan@srnl.doe.go

    2010-11-01

    The UK's National Nuclear Laboratory (NNL) has developed a remote, non-electrical, radiation-mapping device known as RadBall{sup TM}, which can locate and quantify radioactive hazards within contaminated areas of the nuclear industry. RadBall{sup TM} consists of a colander-like outer shell that houses a radiation-sensitive polymer sphere. The outer shell works to collimate radiation sources and those areas of the polymer sphere that are exposed react, becoming increasingly more opaque, in proportion to the absorbed dose. The polymer sphere is imaged in an optical-CT scanner, which produces a high resolution 3D map of optical attenuation coefficients. Subsequent analysis of the optical attenuation matrix provides information on the spatial distribution of sources in a given area forming a 3D characterization of the area of interest. RadBall{sup TM} has no power requirements and can be positioned in tight or hard-to reach locations. The RadBall{sup TM} technology has been deployed in a number of technology trials in nuclear waste reprocessing plants at Sellafield in the UK and facilities of the Savannah River National Laboratory (SRNL). This study focuses on the RadBall{sup TM} testing and modeling accomplished at SRNL.

  20. Secondary reconstruction of severe contracted eye socket using modified ocular conformer-drainage tube system.

    Science.gov (United States)

    Li, Jin; Lin, Ming; Ge, Shengfang; Fan, Xianqun

    2012-07-01

    Eye socket reconstruction has been previously reported; however, few reports address reconstruction in cases of socket contracture after graft failure. This is a retrospective observational case study of 42 patients who had previously undergone eye socket reconstruction after posttraumatic enucleation owing to severe thermal or chemical injury, and each of whom presented with a severe contracted eye socket. Patients underwent free skin grafts and the placement of a modified ocular conformer-drainage tube system. Eye sockets of adequate size were created in the 42 patients. Three patients presented with gradual extrusion of the eye prosthesis due to recurrent contraction of the inferior fornix after treatment. These patients agreed to further operative procedures 6 months after secondary reconstruction surgery, which resulted in mild upward tilting of the eye prosthesis without extrusion. The prosthetic eyes fit well in all of the secondary reconstructed sockets using this technique. Our studies suggest that the modified ocular conformer-drainage tube system can efficiently control infection after secondary reconstruction of the posttraumatic contracted socket and may result in less shrinkage of skin grafts.

  1. Komposit Laminate Rami Epoksi Sebagai Bahan Alternatif Socket Prosthesis

    Directory of Open Access Journals (Sweden)

    Agustinus P. Irawan

    2009-01-01

    Full Text Available pure plant oil, biofuel, coconut oil, palm oil, jatropha oilSocket is the most important component in a prosthesis making. Performance criteria for prosthetic socket material include strength, durability, minimal weight, comfort, and minimal fabrication cost. This research attempts to analyze the strength of ramie fiber reinforced epoxy laminate composite as an alternative of socket prosthesis. The research based on ASTM D 3039/D 3039M for tensile strength and ASTM D 695 for compressive strength. The ramie fiber used was a continuous fiber 100 % Ne14'S, with Epoxy Resin Bakelite EPR 174 and Epoxy Hardener V-140. The sample test was created using a hand lay-up method. The result of this research is presented in a correlation of finsile strength (st, compression strength (sc, elasticity modulus (E versus fraction volume of fiber (Vf. The result is then being compared with some of the prosthesis material’s strength produced by Otto Bock. The analysis was completed with the mode of the failure observation by using Scanning Electron Microscope (SEM. The result concludes that the ramie fiber reinforced epoxy laminate composite is potentially developed further as a socket prosthesis material on Vf 40 – 50 %. Tensile strength and specific strength that has been generated was higher than that of several materias for socket prosthesis, including fiberglass. The mode of the failure found were a brittle failure on Vf: 10-30%, debonding and delamination on Vf: 40-50%. Abstract in Bahasa Indonesia: Socket merupakan bagian terpenting dalam pembuatan prosthesis. Kriteria bahan socket prosthesis antara lain kekuatan, ketahanan, ringan, kenyamanan dan biaya produksi yang rendah. Penelitian ini bertujuan menganalisis kekuatan komposit laminate berpenguat serat rami epoksi sebagai bahan alternatif socket prosthesis. Pengujian kekuatan mengacu standar ASTM D 3039/D 3039M uji tarik dan ASTM D 695 uji tekan. Serat rami yang digunakan berupa serat kontinyu jenis

  2. Formation Mechanism and Characteristics Research of Ball Lightning Based on Vortex Model

    Institute of Scientific and Technical Information of China (English)

    LI Zi-Cheng; YANG Guo-Hua

    2011-01-01

    The strange characteristics of ball lightning are considered as a question hard to explain. In order to solve the problem, in this paper a complete model of plasma vortex is presented for the ball lightning. By ideal MHD equations,through imposing disturbance to plasma column, the possibility of sausage and kink instability of the lightning channel is analyzed from the perspective the minimum potential energy. The conclusion is that the kink instability (m = 1) is most prone to occur. And when instability occurs, because of the difference of the magnetic field in the twisted area,the magnetic pressure makes the trend further and therefore forming the plasma vortex that may eventually turn into ball lightning if the energy of the vortex is large enough. The existence of the vortex makes ball lightning have a short period of time stability. By the proposed model, the ball lightning features that are hard to understand in the past are explained. In this paper, the reason for bead lightning is also explained from the perspective of the sausage instability.

  3. Enhancing the Bounce of a Ball

    Science.gov (United States)

    Cross, Rod

    2010-01-01

    In sports such as baseball, softball, golf, and tennis, a common objective is to hit the ball as fast or as far as possible. Another common objective is to hit the ball so that it spins as fast as possible, since the trajectory of the ball through the air is strongly affected by ball spin. In an attempt to enhance both the coefficient of…

  4. 基于低功耗蓝牙和WebSocket的物联网数据网关%Data Gateway B ased on Low Energy Bluetooth and WebSocket for Internet of Things

    Institute of Scientific and Technical Information of China (English)

    谢佳柏; 陈贤祥; 胡欣宇; 方震; 任仁; 夏善红

    2016-01-01

    为提高低功耗蓝牙( BLE)物联网对移动终端如手机、平板电脑和笔记本电脑的兼容性,文中利用NI myRIO设备和CC2540 BLE适配器设计了一款基于BLE和WebSocket 的数据网关,其软件架构包括WebSocket 网络层、主线程和BLE驱动,能同时连接多个BLE传感器节点并与移动终端通过WebSocket 进行数据交互,用户可在移动终端的浏览器页面控制传感器的工作状态并实时接收传感器采集的最新数据。测试结果表明该网关可实时接收3个BLE振动传感器节点的采样数据,并可远程控制传感器的采样通道、采样率等工作参数。%To improve the compatibility of BluetoothL-ow-Energy(BLE)-based Internet of Things with mobile terminals such as mobile phones , tablet computers and laptop computers, a NI myRIO device and a CC 2540 BLE adapter were used to design a data gateway based on BLE and WebSocket , and its software architecture was made up of a WebSocket network layer , a main thread and a BLE driver.The data gateway can keep multiple connections with BLE sensor nodes and exchange data through Web -Socket with mobile terminals ,thus users can control the working conditions and receive the latest data of the sensors real -time via browser pages of the mobile terminals.The test results show that the data gateway can receive the sampling data of three BLE vibra -tion sensor nodes real-time and control the working parameters such as sampling channels and sampling rate of the sensors remote -ly.

  5. Plasma balls in large-N gauge theories and localized black holes

    International Nuclear Information System (INIS)

    We argue for the existence of plasma balls-metastable, nearly homogeneous lumps of gluon plasma at just above the deconfinement energy density-in a class of large-N confining gauge theories that undergo first-order deconfinement transitions. Plasma balls decay over a time scale of order N2 by thermally radiating hadrons at the deconfinement temperature. In gauge theories that have a dual description that is well approximated by a theory of gravity in a warped geometry, we propose that plasma balls map to a family of classically stable finite-energy black holes localized in the IR. We present a conjecture for the qualitative nature of large-mass black holes in such backgrounds and numerically construct these black holes in a particular class of warped geometries. These black holes have novel properties; in particular, their temperature approaches a nonzero constant value at large mass. Black holes dual to plasma balls shrink as they decay by Hawking radiation; towards the end of this process, they resemble ten-dimensional Schwarzschild black holes, which we propose are dual to small plasma balls. Our work may find practical applications in the study of the physics of localized black holes from a dual viewpoint

  6. General joint hypermobility and temporomandibular joint derangement in adolescents.

    OpenAIRE

    Westling, L; Mattiasson, A.

    1992-01-01

    Joint mobility was assessed in each member of an epidemiological sample of 96 girls and 97 boys, 17 years old, and graded by means of the hypermobility score of Beighton et al. Twenty two per cent of the girls and 3% of the boys could perform five or more of the nine manoeuvres. The prevalence of symptoms and signs of internal derangement in the temporomandibular joint was higher in adolescents with hypermobility of joints (score greater than or equal to 5/9). In subjects with a high mobility...

  7. 76 FR 60871 - Ball Bearings and Parts Thereof From France, Germany, and Italy; Termination of Five-Year Reviews

    Science.gov (United States)

    2011-09-30

    ... deadline.'' (76 FR 57019). Accordingly, pursuant to section 751(c) of the Tariff Act of 1930 (19 U.S.C... COMMISSION Ball Bearings and Parts Thereof From France, Germany, and Italy; Termination of Five-Year Reviews... ball bearings and parts thereof from France, Germany, and Italy would be likely to lead to...

  8. Study and implementation of Web real-time communication mechanism based on HTML5 WebSocket%基于HTML5 WebSocket的Web实时通信机制的研究与实现∗

    Institute of Scientific and Technical Information of China (English)

    陈丽枫; 郑力新; 王佳斌

    2016-01-01

    随着互联网技术的不断发展,Web技术在各个领域得到了不同程度的运用,人们对于Web应用的实时性提出了更高的要求,HTML5 WebSocket协议因此得到了广泛的关注。通过对基于HTTP的传统Web实时通信方案进行分析,针对其中的不足与缺点,深入介绍了基于HTML5 WebSocket协议的实时通信机制以及相对于传统方案的优势,并通过使用Node. js的Express框架和HTML5 WebSocket协议的第三方应用程序编程接口 Socket. io类库实现了一个基于WebSocket协议的Web应用。经实验表明,所描述的研究能成功地在客户端和服务器端完成基于HTML5 WebSocket协议的实时通信过程并建立连接。%With the development of Internet technology,Web technology has been applied in various fields , and people put forward higher re-quirements to the real-time of Web application. So HTML5 WebSocket protocol gets a lot of attention. Through the analysis of the traditional Web real-time communication scheme based on HTTP,for the deficiencies and disadvantages of HTTP, this paper introduces the real-time communication mechanism based on the HTML5 WebSocket protocol and the advantages compared with the traditional solutions. By using the Express framework of Node. js and third party application programming interface Socket. io library of HTML5 WebSocket protocol, it implements a Web application based on WeBsocket protocol. The experiment shows that it can successfully complete the process of real-time communication based on the HTML5 WebSocket protocol and establish a connection between the client and server.

  9. Theory of ball lightning

    CERN Document Server

    Wu, H -C

    2014-01-01

    We present a comprehensive explanation on ball lightning, a luminous sphere occasionally witnessed after ordinary lightning. In the last decade, it has been well established that natural lightning routinely generates relativistic electrons, which account for observed x rays. So we assume that, in a ball lightning event, a well-defined relativistic electron bunch is produced by the stepped leader of lightning. When this electron bunch strikes various media, a powerful microwave pulse is emitted by the coherent transition radiation mechanism. This intense microwave ionizes air, evacuates plasmas by its radiation pressure to form a globular plasma cavity, and then gets trapped inside the cavity. This theory successfully explains all characteristics of ball lightning, especially the appearance of ball lightning in fully-screened aircraft. Moreover, the proposed radiation mechanism fully explains the strongest radio signals from lightning and nanosecond spikes in the signals are direct evidences on the generation ...

  10. 76 FR 2647 - Ball Bearings and Parts Thereof From France, Germany, Italy, Japan, and the United Kingdom...

    Science.gov (United States)

    2011-01-14

    ... Revocation in Part, 75 FR 37759 (June 30, 2010). The preliminary results of the reviews are currently due no... International Trade Administration Ball Bearings and Parts Thereof From France, Germany, Italy, Japan, and the...) initiated administrative reviews of the antidumping duty orders on ball bearings and parts thereof...

  11. Joint probabilities and quantum cognition

    CERN Document Server

    de Barros, J Acacio

    2012-01-01

    In this paper we discuss the existence of joint probability distributions for quantum-like response computations in the brain. We do so by focusing on a contextual neural-oscillator model shown to reproduce the main features of behavioral stimulus-response theory. We then exhibit a simple example of contextual random variables not having a joint probability distribution, and describe how such variables can be obtained from neural oscillators, but not from a quantum observable algebra.

  12. WebSockets - technologie pro tvorbu real time webových aplikací

    OpenAIRE

    Bulvas, Vít

    2012-01-01

    This work deals with the description of the technology HTML5 WebSockets that allows to communicate in real-time between a server and a web application. The theoretical part of this work describes the importance of this technology and compares it with earlier approaches for real-time communication within web applications including the benefits and possible negatives. This work includes a view on current versions of two WebSockets specifications. It means both WebSocket Protocol that enables tw...

  13. The effect of short-term Swiss ball training on core stability and running economy.

    Science.gov (United States)

    Stanton, Robert; Reaburn, Peter R; Humphries, Brendan

    2004-08-01

    The purpose of this study was to investigate the effect of a short-term Swiss ball training on core stability and running economy. Eighteen young male athletes (15.5 +/- 1.4 years; 62.5 +/- 4.7 kg; sigma9 skinfolds 78.9 +/- 28.2 mm; VO2max 55.3 +/- 5.7 ml.kg(-1).min(-1)) were divided into a control (n = 10) and experimental (n = 8) groups. Athletes were assessed before and after the training program for stature, body mass, core stability, electromyographic activity of the abdominal and back muscles, treadmill VO2max, running economy, and running posture. The experimental group performed 2 Swiss ball training sessions per week for 6 weeks. Data analysis revealed a significant effect of Swiss ball training on core stability in the experimental group (p core stability without concomitant improvements in physical performance in young athletes. Specificity of exercise selection should be considered. PMID:15320664

  14. THE INFLUENCE OF BALL VELOCITY AND COURT ILLUMINATION ON REACTION TIME FOR TENNIS VOLLEY

    Directory of Open Access Journals (Sweden)

    Jui-hung Tu

    2010-03-01

    Full Text Available The he purpose of this study is to examine the effects of ball velocity, court illumination, and volley type on the reaction time (RT of a tennis athlete for a volley stroke. Eights cases with two different ball velocities (high and low, two volley types (forehand and backhand and two court illumination levels (dark and bright were studied. The 30 participating subjects consisted of 18 male and 12 female college tennis athletes (age: 24 ± 3.2 yr, with a United States Tennis Association (USTA ranking above 2.5. In order to ensure the validity of real-world correlations, the experiments were designed to simulate real competition situations. Reaction times were measured for volley strokes in response to different approaching ball velocities (high: 25.05 ± 0.37 m/s and low: 17.56 ± 0.92 m·s-1 for several volley types (forehand and backhand and court illumination levels (55649 ± 4292 lux and 363.24 ± 6.53 lux on the court. During the tests, the signals from an electromyogram sensor and a 3-axis accelerometer (± 50 g were recorded using an NI DAQ card (NI PXI-6251 and then analyzed to determine reaction time (RT, premotor reaction time (PRT, and motor reaction time (MRT through the LabVIEW system. Subsequent 3-way ANOVA analysis indicated no RT, PRT, or MRT interaction between ball velocity, volley type and illumination. The ball velocity and illumination parameters did affect RT and PRT values significantly with p < 0.05, no significant variation in MRT was observed across any implemented experimental conditions. All experimental results indicate that ball velocity and illumination levels strongly affect the value of PRT, but have no significant effect on the value of MRT, the changes in RT were dominated by PRT

  15. Aerodynamics of sports balls

    Science.gov (United States)

    Mehta, R. D.

    1985-01-01

    Research data on the aerodynamic behavior of baseballs and cricket and golf balls are summarized. Cricket balls and baseballs are roughly the same size and mass but have different stitch patterns. Both are thrown to follow paths that avoid a batter's swing, paths that can curve if aerodynamic forces on the balls' surfaces are asymmetric. Smoke tracer wind tunnel tests and pressure taps have revealed that the unbalanced side forces are induced by tripping the boundary layer on the seam side and producing turbulence. More particularly, the greater pressures are perpendicular to the seam plane and only appear when the balls travel at velocities high enough so that the roughness length matches the seam heigh. The side forces, once tripped, will increase with spin velocity up to a cut-off point. The enhanced lift coefficient is produced by the Magnus effect. The more complex stitching on a baseball permits greater variations in the flight path curve and, in the case of a knuckleball, the unsteady flow effects. For golf balls, the dimples trip the boundary layer and the high spin rate produces a lift coefficient maximum of 0.5, compared to a baseball's maximum of 0.3. Thus, a golf ball travels far enough for gravitational forces to become important.

  16. Aerodynamics of sports balls

    Science.gov (United States)

    Mehta, R. D.

    Research data on the aerodynamic behavior of baseballs and cricket and golf balls are summarized. Cricket balls and baseballs are roughly the same size and mass but have different stitch patterns. Both are thrown to follow paths that avoid a batter's swing, paths that can curve if aerodynamic forces on the balls' surfaces are asymmetric. Smoke tracer wind tunnel tests and pressure taps have revealed that the unbalanced side forces are induced by tripping the boundary layer on the seam side and producing turbulence. More particularly, the greater pressures are perpendicular to the seam plane and only appear when the balls travel at velocities high enough so that the roughness length matches the seam heigh. The side forces, once tripped, will increase with spin velocity up to a cut-off point. The enhanced lift coefficient is produced by the Magnus effect. The more complex stitching on a baseball permits greater variations in the flight path curve and, in the case of a knuckleball, the unsteady flow effects. For golf balls, the dimples trip the boundary layer and the high spin rate produces a lift coefficient maximum of 0.5, compared to a baseball's maximum of 0.3. Thus, a golf ball travels far enough for gravitational forces to become important.

  17. OH Radical and a Drizzling Water Jet Production from the Ball-Lightning Discharge in Water

    Science.gov (United States)

    Maeyama, Mitsuaki; Tanaka, Yasutomo

    The ball lightning, or fireball discharge using the typical electrode configuration was reported to produce a long-living spherical plasmoid with radius exceed 10 cm at atmospheric pressure. In this study, we investigated the relationship between a optical output emitted from OH radicals and discharge conditions of the ball-lightning electrode configuration, and discussed its possibility to the water treatment process. As a results, in both polarity cases of the charged voltage V0, a ball-lightning discharge and the optical emission from OH radicals as a major radiation can be generated on the condition |V0| > 4 kV in tap water. Furthermore, an intensive upward water jet from the rod electrode is observed in case of positive polarity and in 0.2% NaCl solution, which is composed of drizzling water drops near the rod electrode.

  18. Open collagen membrane technique in socket preservation.

    Science.gov (United States)

    Cheng, Wen-Yen

    2016-01-01

    Both hard and soft tissue undergo change after tooth extraction. In particular, the bone tissue surrounding teeth with fenestration or dehiscence defects undergoes dramatic change following tooth extraction, which can compromise further rehabilitation of the area. Adequate alveolar bone volume and keratinized mucosa are critical to the success of implant therapy. Therefore, the anatomic dimension of the alveolar ridge must be adequate to achieve an esthetically acceptable outcome of implant therapy. Previous studies have proposed many clinical techniques for preserving the extraction socket. This article presents a procedure in which an open collagen membrane technique was adopted to maintain an adequate volume of hard tissue and a sufficient width of the keratinized mucosa for further esthetic and functional implantation. Through this simple technique, an adequate volume and architecture around the implant can be achieved, with a long-term prognosis for implant therapy expected. PMID:27433553

  19. TEMPOROMANDIBULAR-JOINT OSTEOARTHROSIS AND TEMPOROMANDIBULAR-JOINT HYPERMOBILITY

    NARCIS (Netherlands)

    DIJKSTRA, PU; DEBONT, LGM; DELEEUW, R; STEGENGA, B; BOERING, G

    1993-01-01

    For studying the relationship between condylar hypermobility of the temporomandibular joint (TMJ) and osteoarthrosis (OA), 13 patients with bilateral condylar hypermobility were evaluated clinically and radiographically, 30 years after non-surgical treatment. The evaluation included range of motion,

  20. Black hole, string ball, and p-brane production at hadronic supercolliders

    International Nuclear Information System (INIS)

    In models of large extra dimensions, the string and Planck scales become accessible at future colliders. When the energy scale is above the string scale or Planck scale a number of interesting phenomena occur, namely, production of stringy states, p-branes, string balls, black hole, etc. In this work, we systematically study the production cross sections of black holes, string balls, and p-branes at hadronic supercolliders. We also discuss their signatures. At the energy scale between the string scale Ms and Ms/gs2, where gs is the string coupling, the production is dominated by string balls, while beyond Ms/gs2 it is dominated by black holes. The production of a p-brane is only comparable to black holes when the p-brane wraps entirely on small extra dimensions. Rough estimates on the sensitivity reaches on the fundamental Planck scale MD are also obtained, based on the number of raw events

  1. Effect of high-energy ball milling in the structural and textural properties of kaolinite

    Directory of Open Access Journals (Sweden)

    E. C. Leonel

    2014-06-01

    Full Text Available Through the process of high-energy ball milling it is possible to obtain solid materials with higher surface area and different particle sizes. These characteristics are very important for some application such as adsorption. Besides, applications of some clays depend on the functionalization which, for kaolinite, takes place in the aluminol groups. Modification in the structural and textural properties of kaolinite by high-energy milling can improve functionalization of kaolinite due to the exposure of aluminol groups. In this work studies were done on the influence of high-energy ball milling on the morphological properties of kaolinite, taking into account parameters such as filling of the miller, number of balls and amount of mass to be milled. Moreover, studies involving milling kinetics of purified kaolinite were carried out to verify modification in the morphology of kaolinite with milling time.

  2. Research on the Internationalization Trend for the Development of Worldwide Competitive Ball Games and Our Countermeasures

    Institute of Scientific and Technical Information of China (English)

    Yixin Ma

    2015-01-01

    With the progress of physical and sports industry in the world, the analysis of sport industry in China is greatly needed. In this paper, we take discussion the internationalization trend for the development of worldwide competitive ball games and our countermeasures. With the acceleration of global economic integration the frequent personnel exchanges between different countries and nations, nationalities has change.. Physical exercise is beneficial for enhancing national constitution and physique in China, and achieving higher level of national constitution and competitive application in China. Through the proposed research, we could obtain positive development of Chinese competitive ball ~ames' development and harvest.

  3. Microstructure Evolution of Ti/BN Powder Blend during Ball Milling and Heat Treatment

    Institute of Scientific and Technical Information of China (English)

    Jianlin LI; Keao HU; Yong ZHONG

    2001-01-01

    Ball milled Ti/BN composite powder was prepared by high energy ball milling for 40 h, using Ti and BN (the molar ratio of Ti/BN is 3:2) as starting materials. The as-milled composite powder consists of TiN, Ti and amorphous phase. TiN formed while the milled powder was annealed at 400℃. The heat treatment at 700℃ led to the formation of TiB2 and TiB. The nanocrystalline Ti and amorphous phase converted to TiN and TiB2 when the powder was heated to 1300℃.

  4. Titania Prepared by Ball Milling: Its Characterization and Application as Liquefied Petroleum Gas Sensor

    CERN Document Server

    Yadav, B C; Singh, Satyendra; Yadav, T P

    2012-01-01

    Present paper reports the LPG sensing of TiO2 obtained through ball milling. The milled powder was characterized by XRD, TEM and UV-visible spectroscopy. Further the ball milled powder was compressed in to pellet using hydraulic press. This pellet was investigated with the exposure of LPG. Variations in resistance with exposure of LPG to the sensing pellet were recorded. The sensitivity of the sensor was ~ 11 for 5 vol.% of LPG. Response and recovery times of the sensor were ~ 100 and 250 sec. The sensor was quite sensitive to LPG and results were found reproducible within 91%.

  5. Non-linear dynamics and contacts of an unbalanced flexible rotor supported on ball bearings

    OpenAIRE

    Sinou, Jean-Jacques

    2009-01-01

    This study deals with the non-linear dynamic response of a flexible rotor supported by ball bearings. The excitation is due to unbalance force. The finite element rotor system is composed of a shaft with one disk, two flexible bearing supports and a ball bearing element where the non-linearities are due to both the radial clearance and the Herztian contact between races and rolling elements. A numerical analysis is performed to analyze the non-linear behavior of this bearing rotor by using th...

  6. Combination of Aloe vera and xenograft induction on decreasing of NF-kb of tooth extraction socket preservation in Cavia cobaya

    Directory of Open Access Journals (Sweden)

    Utari Kresnoadi

    2014-03-01

    Full Text Available Background: Tooth extraction can naturally cause inflammation triggering osteoclast proliferation and alveolar bone resorption. Preservation of the tooth extraction sockets is needed for patients in order to reduce alveolar bone resorption risks. Aloe vera is known to have anthraquinones components, namely Aloin, Aloe emedin, and barbaloin, considered as anti-inflammation. Therefore, to overcome the inflammation, the role of NF-kb is very significant to decrease nuclear factor kappa b (NF-kb. As a result, inflammation risks will be decreased. Purpose: The study was aimed to determine the induction effect of combination of Aloe vera and XCB into tooth extraction sockets to reduce inflammation by reducing NF-kb expression, osteoclasts and osteoblasts. Methods: Forty-eight Cavia cobaya were divided into eight groups, each group consisted of six animals. The mandibular incisors of those Cavia cobaya were extracted and induced with either PEG, XCB, Aloe vera, or the combination of Aloe vera + XCB. Those animals were sacrificed on day 7 and day 30 after the extraction. Then immunohistochemical and histopathology examinations were conducted to observe NF-kb expression, osteoblasts and osteoclasts. Results: It was known that in group induced with the combination of Aloe vera and xenograft concelous bovine, the growth of osteoblasts was high, while NF-kb expression and osteoclasts reduced. Conclusion: It can be concluded that the induction of the combination of Aloe vera and XCB into the tooth extraction sockets can reduce NF-kb expression and osteoclast, as a result, alveolar bone resorption risks decrease, and osteoblast increase.Latar belakang: Trauma mekanis akibat pencabutan gigi asli menyebabkan keradangan. Keradangan memicu proliferasi osteoklas sehingga menyebabkan resorpsi tulang alveolararis. Pada pembuatan gigi tiruan, resorpsi tulang alveolar yang terjadi, sangat tidak diinginkan, sebab resorpsi tulang alveolar mengurangi keberhasilan

  7. THE SWISS BALL AND ITS USE IN PHYSICAL EDUCATION

    Directory of Open Access Journals (Sweden)

    Niculescu Ionela

    2009-06-01

    Full Text Available Each Physical Education lesson begins by warming-up, a phase when the exercises must be nice andhave to eliminate the tension accumulated during the other classes. The Swiss balloon actions allow us to noticethe manner in which our body is capable of working in all three plans (forward, backwards, lateral.Before beginning training, it is especially important that we very well know the Swiss balloonsexercises, for these not only solicit the great muscular groups, but also the deeper ones, not forgetting themuscles from around joints.The unstable surface of the Swiss balloon forces us to focus on the stabilizing muscles. If this condition is not fulfilled, we are not able to practice any exercise. Right before each particular execution, the muscles of the energy center must be contracted. (the area surrounding the basin, the back and the bottom.The balloon shapes are adapted to the natural curves of the backbone and through their unstable surface force the body to establish equilibrium and keep this state of balance, the moves being perfectly coordinated

  8. Experimental and Numerical Analysis of the Shear Behaviour of Cemented Concrete-Rock Joints

    Science.gov (United States)

    Tian, H. M.; Chen, W. Z.; Yang, D. S.; Yang, J. P.

    2015-01-01

    The shear behaviour of cemented concrete-rock joints is a key factor affecting the shear resistance of dam foundations, arch bridge foundations, rock socketed piles and rock bolts in rock engineering. This paper presents an experimental and numerical investigation of the shear behaviour of cemented concrete-rock joints by direct shear tests. In this study we focused on the bond strength of cemented concrete-rock joints, so limestone with smooth surfaces was used for samples preparation to reduce the roughness effect. The experimental results show that the shear strength of joints with good adhesion is strongly dependent on the bond strength of the cohesive interfaces when the applied normal stress is less than 6 MPa. In addition, the sudden and gradual bond failure processes of the cohesive interfaces were observed with an increase of the normal stress. A simple, yet realistic, model of cemented concrete-rock joint is proposed to simulate the observed behaviour, including elastic behaviour of the bond before peak shear stress and post-peak behaviour due to bond failure and friction increase. Finally, the parameters analysis and calibration of the proposed model are presented.

  9. 75 FR 41435 - Ball Bearings and Parts Thereof From Germany: Notice of Court Decision Not in Harmony With Final...

    Science.gov (United States)

    2010-07-16

    ... and Rescission of Reviews in Part, 73 FR 52823 (September 11, 2008). SKF USA Inc., SKF France S.A... International Trade Administration Ball Bearings and Parts Thereof From Germany: Notice of Court Decision Not in... the administrative review of the antidumping duty order on ball bearings and parts thereof...

  10. Effect of Ball Mass on Dribble, Pass, and Pass Reception in 9-11-Year-Old Boys' Basketball

    Science.gov (United States)

    Arias, Jose L.; Argudo, Francisco M.; Alonso, Jose I.

    2012-01-01

    The objective of the study was to analyze the effect of ball mass on dribble, pass, and pass reception in real game situations in 9-11-year-old boys' basketball. Participants were 54 boys identified from six federated teams. The independent variable was ball mass, and dependent variables were number of dribbles, passes, and pass receptions. Three…

  11. THEORETICAL AND EXPERIMENTAL STUDIES OF ENERGY-EFFICIENT GRINDING PROCESS OF CEMENT CLINKER IN A BALL MILL

    Directory of Open Access Journals (Sweden)

    Kuznetsova M.M.

    2014-08-01

    Full Text Available The article presents results of theoretical and experimental research of grinding process of bulk materials in a ball mill. The new method of determination of energy efficiently mode of operation of ball mills in a process of a cement clinker grinding is proposed and experimentally tested.

  12. Computer-Guided Implant Surgery in Fresh Extraction Sockets and Immediate Loading of a Full Arch Restoration: A 2-Year Follow-Up Study of 14 Consecutively Treated Patients

    OpenAIRE

    2015-01-01

    Statement of Problem. Low scientific evidence is identified in the literature for combining implant placement in fresh extraction sockets with immediate function. Moreover, the few studies available on immediate implants in postextraction sites supporting immediate full-arch rehabilitation clearly lack comprehensive protocols. Purpose. The purpose of this study is to report outcomes of a comprehensive protocol using CAD-CAM technology for surgical planning and fabrication of a surgical templa...

  13. WebSocket与MQTT在Web即时通信系统中的应用%Application of WebSocket and MQTT in Web Real-Time Communication System

    Institute of Scientific and Technical Information of China (English)

    刘峰; 陈朴; 贾军营

    2016-01-01

    传统Web通信系统多采用轮询拉取方式,此种方式存在实时性低、网络资源消耗大、扩展性差等缺点。针对上述问题,本文研究了WebSocket中的长连接技术,结合MQTT协议,提出了基于pub/sub模型的Web端即时通信解决方案,以推送取代传统拉取方式。文中重点阐述了 IM 与通知类消息格式设计,并针对通知类消息提出了 agent 代理模型,同时为了进一步减少网络资源消耗,提出了预订阅模式。最后将该解决方案与现流行的bosh+xmpp方式在时延、带宽消耗方面做了对比分析,以验证该方案的性能优势。%Polling pull strategy, which is widely used in traditional web communication system, has some problems, such as low real-time, heavy consumption of network resource and poor scalability. To solve these problems, much research about long connection technology in WebSocket has been done in the paper. Combining WebSocket with MQTT protocol, a new web instant messaging solution based on pub/sub model was proposed to replace polling strategy with push strategy. The formation design of IM and notification message was described in detail. And agent model was proposed for notification message. Meanwhile, a pre-subscription scheme was put forward to decrease net resource consumption further. Moreover, a comparative analysis on delay, bandwidth consumption between the solution and a current popular way bosh+xmpp was done to verify the advantages of the solution.

  14. Dynamic Investigation of Interface Stress on Below-Knee Residual Limb in a Prosthetic Socket

    Institute of Scientific and Technical Information of China (English)

    贾晓红; 张明; 王人成; 金德闻

    2004-01-01

    The dynamic effects of inertial loads on the interface stresses between a residual limb and the trans-tibial prosthetic socket were investigated. A 3-D nonlinear finite element model, based on the actual geometry of the residual limb, including internal bones and socket liner, was developed to study the mechanical interaction between the socket and the residual limb during walking. To simulate the friction/slip boundary conditions between the skin and liner, automated surface-to-surface contact was used. The results show that interface pressure and shear stress have a similar double-peaked waveform shape in the stance phase. The average difference in interface stresses between the cases with and without consideration of inertial forces is 8.4% in the stance phase and 20.1% in the swing phase. The results suggest that the dynamic effects of inertial loads on interface stress distribution during walking must be considered in prosthetic socket design.

  15. The June surprises: balls, strikes, and the fog of war.

    Science.gov (United States)

    Fried, Charles

    2013-04-01

    At first, few constitutional experts took seriously the argument that the Patient Protection and Affordable Care Act exceeded Congress's power under the commerce clause. The highly political opinions of two federal district judges - carefully chosen by challenging plaintiffs - of no particular distinction did not shake that confidence that the act was constitutional. This disdain for the challengers' arguments was only confirmed when the act was upheld by two highly respected conservative court of appeals judges in two separate circuits. But after the hostile, even mocking questioning of the government's advocate in the Supreme Court by the five Republican-appointed justices, the expectation was that the act would indeed be struck down on that ground. So it came as no surprise when the five opined the act did indeed exceed Congress's commerce clause power. But it came as a great surprise when Chief Justice John Roberts, joined by the four Democrat-appointed justices, ruled that the act could be sustained as an exercise of Congress's taxing power - a ground urged by the government almost as an afterthought. It was further surprising, even shocking, that Justices Antonin Scalia, Anthony Kennedy, Clarence Thomas, and Samuel Alito not only wrote a joint opinion on the commerce clause virtually identical to that of their chief, but that in writing it they did not refer to or even acknowledge his opinion. Finally surprising was the fact that Justices Ruth Bader Ginsburg and Stephen Breyer joined the chief in holding that aspects of the act's Medicaid expansion were unconstitutional. This essay ponders and tries to unravel some of these puzzles.

  16. 75 FR 62763 - Ball Bearings and Parts Thereof From Germany: Amended Final Results of Antidumping Duty...

    Science.gov (United States)

    2010-10-13

    ... Reviews and Rescission of Reviews in Part, 73 FR 52823 (September 11, 2008). SKF USA Inc., SKF France S.A... International Trade Administration Ball Bearings and Parts Thereof From Germany: Amended Final Results of... bearings and parts thereof from Germany. See SKF USA Inc. v. United States, Slip Op. 10-76 (CIT 2010)....

  17. Crystal growth and the steady-state grain size during high-energy ball-milling

    DEFF Research Database (Denmark)

    Mørup, Steen; Jiang, Jianzhong; Bødker, Franz;

    2001-01-01

    The change in crystal size during high-energy ball-milling of hematite and zinc sulphide powders with initial average crystal size of 8 nm and 4 nm, respectively, has been investigated by X-ray powder diffraction and transmission electron microscopy. It is found that the crystal size increases wi...

  18. Modelling of and Conjecturing on a Soccer Ball in a Korean Eighth Grade Mathematics Classroom

    Science.gov (United States)

    Lee, Kyeong-Hwa

    2011-01-01

    The purpose of this article was to describe the task design and implementation of cultural artefacts in a mathematics lesson based on the integration of modelling and conjecturing perspectives. The conceived process of integrating a soccer ball into mathematics lessons via modelling- and conjecturing-based instruction was first detailed. Next, the…

  19. State-of-the-art research in lower-limb prosthetic biomechanics-socket interface: a review.

    Science.gov (United States)

    Mak, A F; Zhang, M; Boone, D A

    2001-01-01

    Scientific studies have been conducted to quantify attributes that may be important in the creation of more functional and comfortable lower-limb prostheses. The prosthesis socket, a human-machine interface, has to be designed properly to achieve satisfactory load transmission, stability, and efficient control for mobility. The biomechanical understanding of the interaction between prosthetic socket and the residual limb is fundamental to such goals. The purpose of this paper is to review the recent research literature on socket biomechanics, including socket pressure measurement, friction-related phenomena and associated properties, computational modeling, and limb tissue responses to external mechanical loads and other physical conditions at the interface. There is no doubt that improved biomechanical understanding has advanced the science of socket fitting. However, the most recent advances in the understanding of stresses experienced at the residual limb have not yet led to enough clinical consensus that could fundamentally alter clinical practice. Efforts should be made to systematically identify the major discrepancies. Further research should be directed to address the critical controversies and the associated technical challenges. Developments should be guided to offer clinicians the quantification and visualization of the interaction between the residual limb and the prosthetic socket. An understanding of comfort and optimal load transfer as patterns of socket interface stress could culminate in socket design expert systems.

  20. Sport’s selection of volley-ball players: morphological and pedagogical criteria of definition of movement endowments: (information 1

    Directory of Open Access Journals (Sweden)

    Leonid Serhiyenko

    2016-02-01

    Full Text Available Purpose: to define methodology of initial sports selection of young volley-ball players. Material & Methods: methods of theoretical analysis and generalization, bibliographic method of search and study of scientific information, a systematic analysis are turned to account in this work. Results: the article deals with the theoretical model of the mast important factors, which define sports endowments of volley-ball players. It is shown the point estimation of body structure and composition, motor and psychomotor abilities, dynamic possibilities, psychophisiological indices in the prognosis of volley-ball players gifted for high sports results. Conclusions: criteria of high movement endowments of volley-ball players are defined; norms of estimation of motor abilities of valley-ball players on the initial steps of sports selection are given.

  1. Management of an irradiated anophthalmic socket following dermis-fat graft rejection: A case report

    Directory of Open Access Journals (Sweden)

    Raizada Kuldeep

    2008-01-01

    Full Text Available Dermis-fat graft (DFG is often the only promising option in cases of severely contracted sockets. However, there is an increased risk of graft failure in irradiated sockets with decreased vascularity. In such difficult cases, repeat DFG implantation also has higher risks of graft failure. We describe an ingenious method of successful management of an irradiated anophthalmic socket following DFG infection and necrosis, with acceptable cosmetic results. At surgery, an orbital impression was taken with ophthalmic grade alginate. Based on this measurement, a custom-made stem pressure socket-expander made up of high density polymethyl methacrylate (PMMA was fitted, a week post surgery and kept in situ for six weeks. On review, the fornices had considerably deepened. The expander device was removed and the patient was now fitted with a custom-made thicker prosthesis made up of high-density PMMA. The patient has followed up for a year subsequently and the prosthesis has remained stable.

  2. Postural Control During Cascade Ball Juggling: Effects of Expertise and Base of Support.

    Science.gov (United States)

    Rodrigues, Sérgio T; Polastri, Paula F; Gotardi, Gisele C; Aguiar, Stefane A; Mesaros, Marcelo R; Pestana, Mayara B; Barbieri, Fabio A

    2016-08-01

    Cascade ball juggling is a complex perceptual motor skill which requires efficient postural stabilization. The aim of this study was to investigate effects of experience (expert and intermediate groups) and foot distance (wide and narrow stances) on body sway of jugglers during three ball cascade juggling. A total of 10 expert jugglers and 11 intermediate jugglers participated in this study. Participants stood barefoot on the force plate (some participants wore a gaze tracking system), with feet maintained in wide and narrow conditions and performed three 40-seconds trials of the three-ball juggling task. Dependent variables were sway mean velocity, amplitude, mean frequency, number of ball cycles, fixation number, mean duration and its variability, and area of gaze displacement. Two-way analyses of variance with factors for group and condition were conducted. Experts' body sway was characterized by lower velocity and smaller amplitude as compared to intermediate group. Interestingly, the more challenging (narrow) basis of support caused significant attenuation in body sway only for the intermediate group. These data suggest that expertise in cascade juggling was associated with refined postural control.

  3. DISSOLUTION OF HOLOCELLULOSE IN IONIC LIQUID ASSISTED WITH BALL-MILLING PRETREATMENT AND ULTRASOUND IRRADIATION

    Directory of Open Access Journals (Sweden)

    Fengxia Yue,

    2012-02-01

    Full Text Available One of the most promising technologies for lignocellulosic biomass utilization employs ionic liquids for the conversion of isolated components into fuels, pharmaceuticals, chemicals, and composites after fractionation of lignocellulose. However, the time required for dissolution of the whole cell wall has been excessive. To explore a possible dissolution and fractionation pathway of lignocelluloses, the dissolution of holocellulose isolated from bagasse was investigated in 1-butyl-3-methylimidazolium chloride ([C4mim]Cl assisted with ball-milling pretreatment and ultrasound irradiation. Ball milling pretreatment, ultrasonic irradiation assistance, and their combination were found to effectively improve the holocellulose dissolution in [C4mim]Cl. The effects of ultrasound power and irradiation duration on the dissolution time of ball-milled holocelluloses in [C4mim]Cl were studied. The regenerated holocelluloses were characterized with FT-IR, X-Ray, and CP/MAS 13C-NMR. It was found that there were no obvious changes of chemical structure after dissolution and regeneration of the holocellulose. The crystalline structure of cellulose was converted from cellulose I in native holocellulose to cellulose II in the regenerated holocellulose. The crystallinity decreased after the process of dissolution and regeneration assisted by ball-milling pretreatment and ultrasound irradiation.

  4. [Divorce and joint physical custody].

    Science.gov (United States)

    Golse, B

    2014-04-01

    This work first recalls the definition of joint physical custody, as well as the current legal procedure for obtaining it, its practical implementation, the financial implications for parents, and finally some statistics. Some psychological and psychopathological reflections on the impact of divorce on children are then presented before considering the question of joint physically custody with regard to attachment theory and depending on the age of the child (a great caution seems to be required before three years). The article concludes with a brief discussion of parental alienation syndrome.

  5. Where is the ball? Behavioral and neural responses elicited by a magic trick.

    Science.gov (United States)

    Caffaratti, Hugo; Navajas, Joaquin; Rey, Hernan G; Quian Quiroga, Rodrigo

    2016-09-01

    We present results from two experiments, in which subjects watched continuous videos of a professional magician repeatedly performing a maneuver in which a ball could "magically" appear under a cup. In all cases, subjects were asked to predict whether the ball would appear under the cup or not, while scalp EEG recordings were performed. Both experiments elicited strong and consistent behavioral and neural responses. In the first experiment, we used two blocks of videos with different probabilities of the ball appearing in the cup and found that, first, based on the behavioral responses, the subjects could track this probability change; and second, the different probabilities modulated the neural responses. In the second experiment, we introduced a control condition in which the magician performed the maneuver under the table, out of subjects' view. Comparing the two conditions (i.e., performing the maneuver within or out of the subjects' view), we found that, first, the magic trick dramatically biased the subjects' behavioral responses; and second, the two conditions led to differential neural responses, in spite of the fact that the stimulus triggering the evoked responses (seeing the ball in the cup) was exactly the same. Altogether, our results show how new insights into sensory and cognitive processing can be obtained using adapted magic tricks. Moreover, the approach of analyzing responses to continuous video presentations offers a more ecological setting compared to classic evoked potential paradigms, which are typically based on presenting static images flashed at the center of the screen. PMID:27356507

  6. Synergism of FAK and tyrosine kinase inhibition in Ph+ B-ALL

    Science.gov (United States)

    Churchman, Michelle L.; Evans, Kathryn; Richmond, Jennifer; Robbins, Alissa; Jones, Luke; Shapiro, Irina M.; Pachter, Jonathan A.; Weaver, David T.; Houghton, Peter J.; Smith, Malcolm A.; Lock, Richard B.; Mullighan, Charles G.

    2016-01-01

    BCR-ABL1+ B progenitor acute lymphoblastic leukemia (Ph+ B-ALL) is an aggressive disease that frequently responds poorly to currently available therapies. Alterations in IKZF1, which encodes the lymphoid transcription factor Ikaros, are present in over 80% of Ph+ ALL and are associated with a stem cell–like phenotype, aberrant adhesion molecule expression and signaling, leukemic cell adhesion to the bone marrow stem cell niche, and poor outcome. Here, we show that FAK1 is upregulated in Ph+ B-ALL with further overexpression in IKZF1-altered cells and that the FAK inhibitor VS-4718 potently inhibits aberrant FAK signaling and leukemic cell adhesion, potentiating responsiveness to tyrosine kinase inhibitors, inducing cure in vivo. Thus, targeting FAK with VS-4718 is an attractive approach to overcome the deleterious effects of FAK overexpression in Ph+ B-ALL, particularly in abrogating the adhesive phenotype induced by Ikaros alterations, and warrants evaluation in clinical trials for Ph+ B-ALL, regardless of IKZF1 status. PMID:27123491

  7. A Randomized Case-Series Study Comparing the Stability of Implant with Two Different Surfaces Placed in Fresh Extraction Sockets and Immediately Loaded

    Science.gov (United States)

    Vanden Bogaerde, Leonardo; Sennerby, Lars

    2016-01-01

    Background. Hydrophilic and moderately rough implant surfaces have been proposed to enhance the osseointegration response. Aim. The aim of this study was to compare early changes of stability for two implants with identical macrodesign but with different surface topographies. Materials and Methods. In 11 patients, a total of 22 implants (11 bimodal (minimally rough, control) and 11 proactive (moderately rough and hydrophilic, test), Neoss Ltd., Harrogate, UK) were immediately placed into fresh extraction sockets and immediately loaded. The peak insertion torque (IT) was measured in Ncm at placement. Resonance Frequency Analysis (RFA) measurements were made at baseline and 2, 4, 6, and 12 weeks after surgery. Results. The two implant types showed similar IT and RFA values at placement (NS). A dip of RFA values after 2 weeks followed by an increase was observed, where the test implant showed a less pronounced decrease and a more rapid recovery than the control implant. The test implants were significantly more stable than the control ones after 12 weeks. Conclusions. The results from the present study indicated that the hydrophilic and rougher test implant was more resistant to immediate loading and showed a significantly higher stability than the smoother control implant after 12 weeks. PMID:27042180

  8. Some Inequalities for Multiple Integrals on the n-Dimensional Ellipsoid, Spherical Shell, and Ball

    Directory of Open Access Journals (Sweden)

    Yan Sun

    2013-01-01

    Full Text Available The authors establish some new inequalities of Pólya type for multiple integrals on the n-dimensional ellipsoid, spherical shell, and ball, in terms of bounds of the higher order derivatives of the integrands. These results generalize the main result in the paper by Feng Qi, Inequalities for a multiple integral, Acta Mathematica Hungarica (1999.

  9. Some Inequalities for Multiple Integrals on the n-Dimensional Ellipsoid, Spherical Shell, and Ball

    OpenAIRE

    Yan Sun; Hai-Tao Yang; Feng Qi

    2013-01-01

    The authors establish some new inequalities of Pólya type for multiple integrals on the n-dimensional ellipsoid, spherical shell, and ball, in terms of bounds of the higher order derivatives of the integrands. These results generalize the main result in the paper by Feng Qi, Inequalities for a multiple integral, Acta Mathematica Hungarica (1999).

  10. Analytical and experimental investigation of the static friction regime for rubber-rigid ball contact

    NARCIS (Netherlands)

    Deladi, E.L.; Rooij, de M.B.; Vries, de E.G; Schipper, D.J.

    2006-01-01

    The static friction regime is of great importance for systems requiring accurate positioning. The parameters of the static friction regime in terms of static friction force and limiting displacement before gross sliding are investigated for a rubber ball/metal flat configuration. Single-asperity fri

  11. Self-generation of machining precision and its realization in lapping of super precision solid balls

    Institute of Scientific and Technical Information of China (English)

    Bopeng ZHANG

    2008-01-01

    This paper presents the principle of self-genera-tion of machining precision by explaining its basic concept and five necessary conditions for forming a system with self-organization capability. A self-generation system is a kind of system with self-organization capability. The self-generation of machining precision for solid balls with super precision is emphatically explained. From the view-point of self-organization, there are three types of systems including system S1 with the self-regulation capability, S2 with the self-determination capability of goals, and S3 with the self-organization capability. Although they are all closed loop control systems, they have different con-structions and functions. Necessary conditions for achiev-ing self-generation of machining precision are given. Establishment of the system for machining solid balls with super precision is discussed. Self-generation of machining precision for solid balls with super precision on the basis of the capability of self-removal of errors is presented. Self-generation includes the ability of self-removal of errors for solid balls, convergence of self-removal of errors, self-generation of precision, and self-generating system for the given.

  12. Relation Between Lift Force and Ball Spin for Different Baseball Pitches.

    Science.gov (United States)

    Nagami, Tomoyuki; Higuchi, Takatoshi; Nakata, Hiroki; Yanai, Toshimasa; Kanosue, Kazuyuki

    2016-04-01

    Although the lift force (FL) on a spinning baseball has been analyzed in previous studies, no study has analyzed such forces over a wide variety of spins. The purpose of this study was to describe the relationship between FL and spin for different types of pitches thrown by collegiate pitchers. Four high-speed video cameras were used to record flight trajectory and spin for 7 types of pitches. A total of 75 pitches were analyzed. The linear kinematics of the ball was determined at 0.008-s intervals during the flight, and the resultant fluid force acting on the ball was calculated with an inverse dynamics approach. The initial angular velocity of the ball was determined using a custom-made apparatus. Equations were derived to estimate the FL using the effective spin parameter (ESp), which is a spin parameter calculated using a component of angular velocity of the ball with the exception of the gyro-component. The results indicate that FL could be accurately explained from ESp and also that seam orientation (4-seam or 2-seam) did not produce a uniform effect on estimating FL from ESp. PMID:26576060

  13. Power/Knowledge for Educational Theory: Stephen Ball and the Reception of Foucault

    Science.gov (United States)

    Wang, Chia-Ling

    2011-01-01

    This paper explores the significance of the concept of power/knowledge in educational theory. The argument proceeds in two main parts. In the first, I consider aspects of Stephen J. Ball's highly influential work in educational theory. I examine his reception of Foucault's concept of power/knowledge and suggest that there are problems in his…

  14. The Secrets of Plasticine Balls and the Structure of the Earth: Investigation through Discussion

    Science.gov (United States)

    King, Chris

    2002-01-01

    Balls made of modelling clay (Plasticine[TM]) can be used to generate a classroom discussion about the scientific evidence used to determine the structure of the Earth. This allows pupils to appreciate how evidence is used to support hypotheses and to distinguish fact from hypothesis. It also provides opportunity to correct misconceptions held by…

  15. Influence of Leukocyte- and Platelet-Rich Fibrin (L-PRF) in the Healing of Simple Postextraction Sockets: A Split-Mouth Study.

    Science.gov (United States)

    Marenzi, Gaetano; Riccitiello, Francesco; Tia, Mariano; di Lauro, Alessandro; Sammartino, Gilberto

    2015-01-01

    The aim of this study was to evaluate the effects of leukocyte- and platelet-rich fibrin (L-PRF) on the pain and soft tissue healing after tooth extractions. Twenty-six patients (9 males and 17 females) were treated with multiple extractions (2 to 8), with a total of 108 extractions. This was an exploratory single blinded randomized clinical trial with a split-mouth design. The pain after the surgery was assessed in each patient by the VAS scale (1 to 10) at intervals of 24-48-72-96 hours. The soft tissue healing was clinically evaluated at 3, 7, 14, and 21 days after surgery by the same examiner surgeon, using the modified Healing Index (4 to 12). The mean value of postextraction pain was 3.2 ± 0.3 in the experimental sides and 4.1 ± 0.1 in the control sides. After 7 days from the extractions, the values of modified Healing Index in the experimental and control groups were, respectively, 4.8 ± 0.6 and 5.1 ± 0.9. The use of L-PRF in postextraction sockets filling can be proposed as a useful procedure in order to manage the postoperative pain and to promote the soft tissue healing process, reducing the early adverse effects of the inflammation.

  16. Numerical study on the aerodynamics of a golf ball and its comparison with a smooth sphere

    Science.gov (United States)

    Li, Jing; Tsubokura, Makoto; Tsunoda, Masaya

    2014-11-01

    The present study has numerically investigated the flow over a golf ball and a smooth sphere by conducting large-eddy simulation (LES) using hundreds of millions of unstructured elements. Simulations were conducted at various Reynolds numbers ranging from the subcritical to the supercritical regimes. Special attention was paid to the phenomenon of drag crisis as well as the effect of surface roughness on the drag crisis. The simulation result shows that the surface roughness introduced by the dimples of the golf ball causes a local instability of the flow around the ball and subsequently leads to a momentum transfer in the near-wall region inside the dimples. The flow with high momentum in the near-wall region travels further downstream, which consequently results in the drag crisis occurring at a relatively lower Reynolds number compared with that of the smooth sphere. Moreover, the Magnus effect resulting from the rotating motion of a sphere was also one of the main concerns in this study. The simulation result shows that lift forces are imposed on both the rotating smooth sphere and rotating golf ball. For most cases the lift force points to the positive direction, however, the negative lift force appears also under certain conditions.

  17. Transmental Sheherazade on the interwar avant-garde balls in Belgrade and Paris

    Directory of Open Access Journals (Sweden)

    Jović Bojan

    2013-01-01

    Full Text Available In expert circles, attention has been drawn to the “1002nd Night Ball” created by the protagonists of Yugoslav and Serbian avant-garde, in particular on its dance and musical segments, moreover, the ballet “Le balai du valet” by Marko Ristić and Miloje Milojević, as well as the ensuing series of balls related to the Association of Friends of Art “Cvijeta Zuzorić”. On the other hand, it is an (almost completely unknown fact that Rade Drainac’s original idea to throw a ball for the benefit of artists and writers that needed financial assistance because of difficult financial situation (later replaced with an initiative to raise funds to build an art pavilion “Cvijeta Zuzorić” matched the idea of the Union of Russian artists in Paris to organize a ball with the aim of contributing to mutual aid. The ball in Paris, with the participation of the most prominent avant-garde artists, took place exactly one week after the Belgrade ball, which also suggests the possible connection / synchronization of these two artistic events. Having this in mind, I offer a brief analysis of the concept and scope of the aforementioned artistic events from the perspective of the intermedia and multimedia strategies. I demonstrate that the Belgrade spectacle was envisioned and performed far more ambitiously than the Parisian one, and the thoroughness of the interweaving of various arts ranks it among those works (including Parade by Cocteau, Picasso and Satie, Skating-Rink by Canudo, Leger, and Honegger, La creation du monde by Cendrars, Léger and Milhaud, with Russian and Swedish Ballet that aimed to achieve a Gesamtkunstwerk, i.e. a total work of avant-garde art. [Projekat Ministarstva nauke Republike Srbije, br. ON 178008: Srpska književnost u evropskom kulturnom prostoru

  18. Evaluation and Description of Friction between an Electro-Deposited Coating and a Ceramic Ball under Fretting Condition

    Directory of Open Access Journals (Sweden)

    Kyungmok Kim

    2015-07-01

    Full Text Available This article describes fretting behavior of zirconia and silicon nitride balls on an electro-deposited coating. Fretting tests are performed using a ball-on-flat configuration. The evolution of the kinetic friction coefficient is determined, along with slip ratio. Experimental results show that the steady-state friction coefficient between ceramic balls (Si3N4 and ZrO2 and an electro-deposited coating is about 0.06, lower than the value between AISI 52100 ball and the coating. After a steady-state sliding, the transition of the friction coefficient is varied with a ball. The friction coefficient for ZrO2 balls became a critical value after higher fretting cycles than those for Si3N4 and AISI 52100 balls. In addition, it is identified that two parameters can describe the transition of the friction coefficient. Finally, the evolution of the friction coefficient is expressed as an exponential or a power-law form.

  19. Plasma-balls in large N gauge theories and localized black holes

    CERN Document Server

    Aharony, O; Wiseman, T; Aharony, Ofer; Minwalla, Shiraz; Wiseman, Toby

    2005-01-01

    We argue for the existence of plasma-balls - meta-stable, nearly homogeneous lumps of gluon plasma at just above the deconfinement energy density - in a class of large N confining gauge theories that undergo first order deconfinement transitions. Plasma-balls decay over a time scale of order N^2 by thermally radiating hadrons at the deconfinement temperature. In gauge theories that have a dual description that is well approximated by a theory of gravity in a warped geometry, we propose that plasma-balls map to a family of classically stable finite energy black holes localized in the IR. We present a conjecture for the qualitative nature of large mass black holes in such backgrounds, and numerically construct these black holes in a particular class of warped geometries. These black holes have novel properties; in particular their temperature approaches a nonzero constant value at large mass. Black holes dual to plasma-balls shrink as they decay by Hawking radiation; towards the end of this process they resembl...

  20. Ball milling improves extractability and affects molecular properties of psyllium (Plantago ovata Forsk) seed husk arabinoxylan.

    Science.gov (United States)

    Van Craeyveld, Valerie; Delcour, Jan A; Courtin, Christophe M

    2008-12-10

    Psyllium (Plantago ovata Forsk) seed husk (PSH) is very rich in arabinoxylan (AX). However, its high gelling capacity and the complex nature of the AX make it difficult to process. In this study, ball milling was investigated as a tool for enhancing PSH AX water extractability and molecular mass (MM). A 48 h laboratory-scale ball mill treatment under standardized optimal conditions reduced the PSH average particle size from 161 microm for the untreated sample to 6 microm. Concurrently, it increased the water-extractable AX (WE-AX) level from 13 (untreated PSH) to 90% of the total PSH AX. While the WE-AX of the untreated PSH had a peak MM of 216 kDa and an arabinose to xylose (A/X) ratio of 0.20, WE-AX fragments from ball mill-pretreated PSH had a peak MM of 22 kDa and an A/X ratio of 0.31. Ball milling further drastically reduced the intrinsic viscosity of PSH extracts and their water-holding capacity. Prolonged treatment brought almost all AX (98%) in solution and yielded WE-AX fragments with an even higher A/X ratio (0.42) and a lower peak MM (11 kDa). While impact and jet milling of PSH equally led to significant reductions in particle size, these technologies only marginally affected the water extractability of PSH AX. This implies that ball milling affects PSH particles and their constituent molecules differently than impact and jet milling. PMID:19007123

  1. Systematic review of effects of current transtibial prosthetic socket designs—Part 1: Qualitative outcomes

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Safari, PhD

    2015-09-01

    Full Text Available This review is an attempt to untangle the complexity of transtibial prosthetic socket fit, determine the most important characteristic for a successful fitting, and perhaps find some indication of whether a particular prosthetic socket type might be best for a given situation. Further, it is intended to provide directions for future research. We followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and used medical subject headings and standard key words to search for articles in relevant databases. No restrictions were made on study design or type of outcome measure. From the obtained search results (n = 1,863, 35 articles were included. The relevant data were entered into a predefined data form that incorporated the Downs and Black risk of bias assessment checklist. Results for the qualitative outcomes (n = 19 articles are synthesized. Total surface bearing sockets lead to greater activity levels and satisfaction in active persons with amputation, those with a traumatic cause of amputation, and younger persons with amputation than patellar tendon bearing sockets. Evidence on vacuum-assisted suction and hydrostatic sockets is inadequate, and further studies are much needed. To improve the scientific basis for prescription, comparison of and correlation between mechanical properties of interface material, socket designs, user characteristics, and outcome measures should be conducted and reported in future studies.

  2. Systematic review of effects of current transtibial prosthetic socket designs-Part 1: Qualitative outcomes.

    Science.gov (United States)

    Safari, Mohammad Reza; Meier, Margrit Regula

    2015-01-01

    This review is an attempt to untangle the complexity of transtibial prosthetic socket fit, determine the most important characteristic for a successful fitting, and perhaps find some indication of whether a particular prosthetic socket type might be best for a given situation. Further, it is intended to provide directions for future research. We followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and used medical subject headings and standard key words to search for articles in relevant databases. No restrictions were made on study design or type of outcome measure. From the obtained search results (n = 1,863), 35 articles were included. The relevant data were entered into a predefined data form that incorporated the Downs and Black risk of bias assessment checklist. Results for the qualitative outcomes (n = 19 articles) are synthesized. Total surface bearing sockets lead to greater activity levels and satisfaction in active persons with amputation, those with a traumatic cause of amputation, and younger persons with amputation than patellar tendon bearing sockets. Evidence on vacuum-assisted suction and hydrostatic sockets is inadequate, and further studies are much needed. To improve the scientific basis for prescription, comparison of and correlation between mechanical properties of interface material, socket designs, user characteristics, and outcome measures should be conducted and reported in future studies.

  3. Surgical treatment about hollow eye socket after enucleation of eyeball and having orbital fracture under endoscope%眼眶骨折眼球摘除术后眼窝凹陷的鼻内镜下手术

    Institute of Scientific and Technical Information of China (English)

    李谊; 朱豫

    2012-01-01

    目的 探讨在鼻内镜下,高密度多聚乙烯(Medpor)植入板联合羟基磷灰石(HA)义眼座植入治疗眼眶骨折眼球摘除后眼窝凹陷的临床效果.方法 对眼眶骨折眼球缺失后眼窝凹陷的156例先行HA义眼座Ⅰ期或Ⅱ期植入,后根据眶骨缺损情况在鼻内镜引导下以Medpor植入板填充修补.结果 156例均获良好效果,可见双眼外观基本对称,上眶区饱满无凹陷,患侧眶缘连续,外形良好.Medpor植入板植入后对义眼座活动度有显著性影响.结论 Medpor植入板眼眶填充联合HA义眼座眶内植入治疗合并眼眶骨折的眼窝凹陷效果良好;尤其是在鼻内镜引导下手术,更能使骨折断端达到完美的结合,并能避免损伤周围正常组织.%Objective To evaluate the clinical effect of the reconstruction of orbital socket with Medpor implant plate for the treatment of hollow eye socket after enucleation of eyeball and orbital fracture under endoscope.Methods 156 cases with hollow eye socket and orbital fracture had been implanted primarily or secondarily with Hydroxyapatite (HA) prosthesis under endoscope.Medpor implant plate reconstruction had been done according to the defection of the orbital bone.Results The results of 156 cases were satisfied,Both sides of the orbit were symmetric on appearance.Superior orbit was full and no depression.The hollow degree of the implants was also symmetric with the other eye.The orbital rims of the affected eye were continuous and in good shape,During the implantation of Medpor implant plate,it would owing significant effect to the motility of HA prosthesis.Conclusion Medpor implant plate should be good material for substitution of the bone,which has good tissue compatability,easy for shape and vascularization and much more better than other materials.Orbital socket reconstration by prosthesis implantation with hydroxyapatite prosthesis combine with Medpor implant plate for the treatment of hollow eye socket and

  4. The bowling balls

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    10 November 1972: CERN’s Bent Stumpe places an order for 12 bowling balls for a total cost of 95 US dollars. Although not evident at first sight, he is buying the heart of some of the first tracking devices to be used in the SPS control room. Today, Bent Stumpe’s device would be called a desktop mouse…   The first order for 4 bowling balls later changed to 12 balls. The bowling balls became the heart of Bent Stumpe's mouse. Almost 40 years ago, the web, Wikipedia and Google did not exist and it was much more difficult to know whether other people in other parts of the world or even in the same laboratory were facing the same problems or developing the same tools. At that time, Bent Stumpe was an electronics engineer, newly recruited to work on developments for the SPS Central Control room. One of the things his supervisor asked him to build as soon as possible was a device to control a pointer on a screen, also called a tracker ball. The heart of the device was the...

  5. Tunguska Dark Matter Ball

    CERN Document Server

    Froggatt, C D

    2014-01-01

    It is suggested that the Tunguska event in June 1908 cm-large was due to a cm-large ball of a condensate of bound states of 6 top and 6 anti-top quarks containing highly compressed ordinary matter. Such balls are supposed to make up the dark matter as we earlier proposed. The expected rate of impact of this kind of dark matter ball with the earth seems to crudely match a time scale of 200 years between the impacts. The main explosion of the Tunguska event is explained in our picture as material coming out from deep within the earth, where it has been heated and compressed by the ball penetrating to a depth of several thousand km. Thus the effect has some similarity with volcanic activity as suggested by Kundt. We discuss the possible identification of kimberlite pipes with earlier Tunguska-like events. A discussion of how the dark matter balls may have formed in the early universe is also given.

  6. Effect of Kinesiotape Applications on Ball Velocity and Accuracy in Amateur Soccer and Handball

    OpenAIRE

    Müller Carsten; Brandes Mirko

    2015-01-01

    Evidence supporting performance enhancing effects of kinesiotape in sports is missing. The aims of this study were to evaluate effects of kinesiotape applications with regard to shooting and throwing performance in 26 amateur soccer and 32 handball players, and to further investigate if these effects were influenced by the players’ level of performance. Ball speed as the primary outcome and accuracy of soccer kicks and handball throws were analyzed with and without kinesiotape by means of rad...

  7. Synchronized Legg-Calve Perthes disease and comorbid perforated appendicitis

    Directory of Open Access Journals (Sweden)

    Alev Süzen

    2015-08-01

    Full Text Available Abdominal pain is a very common complaint caused by a variety of conditions. Acute appendicitis is the most common cause of acute abdominal pain in children requiring surgical intervention. Legg-Calve-Perthes disease (LCPD is a childhood condition that affects the hip, where the thighbone (femur and pelvis meet in a ball-and-socket joint. The disease is initially asymptomatic or there is painless limp. The pain associated with LCPD is often localized in the inguinal region. The present study is aimed to present a patient with LCPD and comorbid perforated appendicitis and to highlight the importance of the differential diagnosis of abdominal pain as a delay in diagnosis can increase the risk of mortality. Analyzing the imaging technique, from the study it has been found out that clinicians should examine all the field about the diagnosis, not only the field around disease as a patient might have two separate acute problems at same time.

  8. Effect of Internal Clearance on Load Distribution and Life of Radially Loaded Ball and Roller Bearings

    Science.gov (United States)

    Oswald, Fred B.; Zaretsky, Erwin V.; Poplawski, Joseph V.

    2012-01-01

    The effect of internal clearance on radially loaded deepgroove ball and cylindrical roller bearing load distribution and fatigue life was determined for four clearance groups defined in the bearing standards. The analysis was extended to negative clearance (interference) conditions to produce a curve of life factor versus internal clearance. Rolling-element loads can be optimized and bearing life maximized for a small negative operating clearance. Life declines gradually with positive clearance and rapidly with increasing negative clearance. Relationships were found between bearing life and internal clearance as a function of ball or roller diameter, adjusted for load. Results are presented as life factors for radially loaded bearings independent of bearing size or applied load. In addition, a modified Stribeck Equation is presented that relates the maximum rolling-element load to internal bearing clearance.

  9. The effects of ball impact location and grip tightness on the arm, racquet and ball for one-handed tennis backhand groundstrokes.

    Science.gov (United States)

    King, Mark A; Kentel, Behzat B; Mitchell, Sean R

    2012-04-01

    A torque-driven, 3D computer simulation model of an arm-racquet system was used to investigate the effects of ball impact location and grip tightness on the arm, racquet and ball during one-handed tennis backhand groundstrokes. The stringbed was represented by nine point masses connected to each other and the racquet frame with elastic springs and three torsional spring-dampers between the hand and the racquet were used to represent grip tightness. For each perturbation of nine impact locations and grip tightness, simulations were run for a 50 ms period starting with ball-racquet impact. Simulations showed that during off-centre impacts below the longitudinal axis of the racquet, the wrist was forced to flex up to 16° more with up to six times more wrist extension torque when compared to a centre impact simulation. Perturbing grip tightness had no substantial effect on centre impact simulations. However, for off-centre impacts (below the longitudinal axis of the racquet) a tight grip condition resulted in a substantial decrease in racquet rotation within the hand (less than 2°) and an increase of 6° in wrist flexion angle when compared to the equivalent simulation with a normal grip. In addition there was approximately 20% more wrist extension torque when compared with equivalent off-centre impact simulation with a normal grip. Consequently off-centre impacts below the longitudinal axis of the racquet may be a substantial contributing factor for tennis elbow injuries with a tight grip aggravating the effect due to high eccentric wrist extension torques and forced wrist flexion. PMID:22325977

  10. Quaternionic Hardy spaces in the open unit ball and half space and Blaschke products

    Science.gov (United States)

    Alpay, Daniel; Colombo, Fabrizio; Sabadini, Irene

    2015-04-01

    The Hardy spaces H2(B) and H2(H+), where B and H+ denote, respectively, the open unit ball of the quaternions and the half space of quaternions with positive real part, as well as Blaschke products, have been intensively studied in a series of papers where they are used as a tool to prove other results in Schur analysis. This paper gives an overview on the topic, collecting the various results available.

  11. Lectures on constructive approximation Fourier, spline, and wavelet methods on the real line, the sphere, and the ball

    CERN Document Server

    Michel, Volker

    2013-01-01

    Lectures on Constructive Approximation: Fourier, Spline, and Wavelet Methods on the Real Line, the Sphere, and the Ball focuses on spherical problems as they occur in the geosciences and medical imaging. It comprises the author’s lectures on classical approximation methods based on orthogonal polynomials and selected modern tools such as splines and wavelets. Methods for approximating functions on the real line are treated first, as they provide the foundations for the methods on the sphere and the ball and are useful for the analysis of time-dependent (spherical) problems. The author then examines the transfer of these spherical methods to problems on the ball, such as the modeling of the Earth’s or the brain’s interior. Specific topics covered include: * the advantages and disadvantages of Fourier, spline, and wavelet methods * theory and numerics of orthogonal polynomials on intervals, spheres, and balls * cubic splines and splines based on reproducing kernels * multiresolution analysis using wavelet...

  12. Frictional action at lower limb/prosthetic socket interface.

    Science.gov (United States)

    Zhang, M; Turner-Smith, A R; Roberts, V C; Tanner, A

    1996-04-01

    The frictional action at stump/socket interface is discussed by a simplified model and finite element model analyses and clinical pressure measurements. The friction applied to the stump skin produces stresses within tissue and these stresses may damage the tissues and affect their normal functions. The combination of normal and shear stresses is considered to be a critical factor leading to amputee's discomfort and tissue damage. However, friction at the stump/socket interface has a beneficial action. A simplified residual limb model and a finite element model using real geometry have been developed to analyse the support action of friction. Both results show that the friction plays a critical role both in supporting the load of the amputee's body during the support phase of the gait cycle and in preventing the prosthesis from slipping off the limb during swing phase. Pressure at the below-knee socket during walking were measured with conditions of different friction. The results reveal that a larger pressures was produced at the lubricated interface than at the normal interface. A proper choice of coefficient of friction will balance the requirements of relief of load stress and reduction of slip with the general ability to support loads.

  13. Design and wear testing of a temporomandibular joint prosthesis articulation

    NARCIS (Netherlands)

    van Loon, JP; Verkerke, GJ; de Vries, MP; de Bont, LGM

    2000-01-01

    As part of the development of a total temporomandibular joint prosthesis, a prosthesis articulation was designed. The articulation consists of a spherical head (ball) of the mandibular part, rotating against an enveloping ultra-high-molecular-weight polyethylene (UHMWPE) disc with a flat cranial sid

  14. Styrofoam-and-Velcro: An Alternative to Ball-and-Stick Models

    Directory of Open Access Journals (Sweden)

    Sawyer Rowan Masonjones

    2014-07-01

    Full Text Available For students learning biology at introductory levels, one of the most significant instructional barriers is their lack of preparation in chemistry. In upper-division college chemistry and biology courses, students employ ball-and-stick models in order to visualize molecular structures, but at the introductory biology level, models are inconsistently used and at the secondary level they are avoided altogether. Traditional ball-and-stick models perform poorly at all levels because they only show bonds, never valence electrons. This poses a problem for students who are visual or kinesthetic learners, as modeling electrons in the bonding process may be critical to understanding the mechanisms behind the biochemical reactions that serve as a foundation for biological concepts. Our molecular modeling kits show the action of valence electrons and correctly deal with the issue of polarity and partial charge, while still illustrating structure and function similarly to ball-and-stick models, allowing students to model nearly every reaction or molecule they may need to learn.  Additionally, this kit will foster model building exercises required as part of the Next Generation Science Standards (http://www.nextgenscience.org/next-generation-science-standards. This model was devloped in conjunction with 'Molecular Twister: A Game for Exploring Solution Chemistry' (JMBE Vol 15, No 1; http://jmbe.asm.org/index.php/jmbe/article/view/652 by the same authors, which uses principles derived from the present paper.

  15. TCP/IP Sockets in C# Practical Guide for Programmers

    CERN Document Server

    Makofske, David; Calvert, Kenneth L

    2004-01-01

    "TCP/IP sockets in C# is an excellent book for anyone interested in writing network applications using Microsoft .Net frameworks. It is a unique combination of well written concise text and rich carefully selected set of working examples. For the beginner of network programming, it''s a good starting book; on the other hand professionals could also take advantage of excellent handy sample code snippets and material on topics like message parsing and asynchronous programming."Adarsh Khare, SDT, .Net Frameworks Team, Microsoft CorporationThe popularity of the C# language and the .NET framework is ever rising due to its ease of use, the extensive class libraries available in the .NET Framework, and the ubiquity of the Microsoft Windows operating system, to name a few advantages. TCP/IP Sockets in C# focuses on the Sockets API, the de facto standard for writing network applications in any programming language. Starting with simple client and server programs that use TCP/IP (the Internet protocol suite), students ...

  16. Technical note: Computer-manufactured inserts for prosthetic sockets.

    Science.gov (United States)

    Sanders, Joan E; McLean, Jake B; Cagle, John C; Gardner, David W; Allyn, Katheryn J

    2016-08-01

    The objective of this research was to use computer-aided design software and a tabletop 3-D additive manufacturing system to design and fabricate custom plastic inserts for trans-tibial prosthesis users. Shape quality of inserts was tested right after they were inserted into participant's test sockets and again after four weeks of wear. Inserts remained properly positioned and intact throughout testing. Right after insertion the inserts caused the socket to be slightly under-sized, by a mean of 0.11mm, approximately 55% of the thickness of a nylon sheath. After four weeks of wear the under-sizing was less, averaging 0.03mm, approximately 15% of the thickness of a nylon sheath. Thus the inserts settled into the sockets over time. If existing prosthetic design software packages were enhanced to conduct insert design and to automatically generate fabrication files for manufacturing, then computer manufactured inserts may offer advantages over traditional methods in terms of speed of fabrication, ease of design, modification, and record keeping. PMID:27212209

  17. 75 FR 26920 - Ball Bearings and Parts Thereof from France, Germany, Italy, Japan, and the United Kingdom...

    Science.gov (United States)

    2010-05-13

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE International Trade Administration Ball Bearings and Parts Thereof from France, Germany, Italy, Japan, and the United Kingdom: Preliminary Results of Antidumping Duty Administrative Reviews, Preliminary Results...

  18. Quality assessment of systematic reviews on alveolar socket preservation.

    Science.gov (United States)

    Moraschini, V; Barboza, E Dos S P

    2016-09-01

    The aim of this overview was to evaluate and compare the quality of systematic reviews, with or without meta-analysis, that have evaluated studies on techniques or biomaterials used for the preservation of alveolar sockets post tooth extraction in humans. An electronic search was conducted without date restrictions using the Medline/PubMed, Cochrane Library, and Web of Science databases up to April 2015. Eligibility criteria included systematic reviews, with or without meta-analysis, focused on the preservation of post-extraction alveolar sockets in humans. Two independent authors assessed the quality of the included reviews using AMSTAR and the checklist proposed by Glenny et al. in 2003. After the selection process, 12 systematic reviews were included. None of these reviews obtained the maximum score using the quality assessment tools implemented, and the results of the analyses were highly variable. A significant statistical correlation was observed between the scores of the two checklists. A wide structural and methodological variability was observed between the systematic reviews published on the preservation of alveolar sockets post tooth extraction. None of the reviews evaluated obtained the maximum score using the two quality assessment tools implemented. PMID:27061478

  19. Scale-up of organic reactions in ball mills: process intensification with regard to energy efficiency and economy of scale.

    Science.gov (United States)

    Stolle, Achim; Schmidt, Robert; Jacob, Katharina

    2014-01-01

    The scale-up of the Knoevenagel-condensation between vanillin and barbituric acid carried out in planetary ball mills is investigated from an engineering perspective. Generally, the reaction proceeded in the solid state without intermediate melting and afforded selectively only one product. The reaction has been used as a model to analyze the influence and relationship of different parameters related to operation in planetary ball mills. From the viewpoint of technological parameters the milling ball diameter, dMB, the filling degree with respect to the milling balls' packing, ΦMB,packing, and the filling degree of the substrates with respect to the void volume of the milling balls' packing, ΦGS, have been investigated at different reaction scales. It was found that milling balls with small dMB lead to higher yields within shorter reaction time, treaction, or lower rotation frequency, rpm. Thus, the lower limit is set considering the technology which is available for the separation of the milling balls from the product after the reaction. Regarding ΦMB,packing, results indicate that the optimal value is roughly 50% of the total milling beakers' volume, VB,total, independent of the reaction scale or reaction conditions. Thus, 30% of VB,total are taken by the milling balls. Increase of the initial batch sizes changes ΦGS significantly. However, within the investigated parameter range no negative influence on the yield was observed. Up to 50% of VB,total can be taken over by the substrates in addition to 30% for the total milling ball volume. Scale-up factors of 15 and 11 were realized considering the amount of substrates and the reactor volume, respectively. Beside technological parameters, variables which influence the process itself, treaction and rpm, were investigated also. Variation of those allowed to fine-tune the reaction conditions in order to maximize the yield and minimize the energy intensity.

  20. Seabasing and joint expeditionary logistics

    OpenAIRE

    Bender, Amy; Cottle, Jacob; Craddock, Timothy; Dowd, Justin; Feese, Rick; Foster, Brett; Gainey, John; Jimenez, Ivan; Johnson, Brent; Johnson, Terry; Lemmon, John; Levendofske, Michael; Liskey, Dale; Oliphant, Anthony; Olvera, Daniel

    2004-01-01

    Includes supplementary material. Recent conflicts such as Operation Desert Shield/Storm and Operation Iraqi Freedom highlight the logistics difficulties the United States faces by relying on foreign access and infrastructure and large supply stockpiles ashore to support expeditionary operations. The Navy's transformational vision for the future, Sea Power 21, involves Seabasing as a way to address these difficulties by projecting and sustaining joint forces globally from the sea. This stud...

  1. Cancer of the Bone and Joint

    Science.gov (United States)

    ... a third party. HPF: SEER Stat Fact Sheets: Bone and Joint Cancer Expand All Collapse All Lifetime risk estimates are ... 5 Years Or More after Being Diagnosed with Bone and Joint Cancer? Relative survival statistics compare the survival of patients ...

  2. Prognosis of motor development and joint hypermobility.

    OpenAIRE

    Tirosh, E; Jaffe, M; Marmur, R; Taub, Y; Rosenberg, Z.

    1991-01-01

    In a study of 59 infants aged 18 months there were 20 with joint hypermobility and delayed motor development, 19 with joint hypermobility and normal motor development, and 20 normal controls. They were reassessed for motor function 3.5 years later at the age of 5 years. Both gross and fine motor performance were significantly delayed in the group of children who exhibited joint hypermobility and motor delay in infancy. No significant delay was evident in those with joint hypermobility only. J...

  3. Microstructure and Physical Properties of Tb2TiO5 Neutron Absorber Synthesized by Ball Milling and Sintering

    Science.gov (United States)

    Huang, Jinghua; Ran, Guang; Liu, Tengjiao; Shen, Qiang; Li, Ning

    2016-08-01

    Tb2TiO5 neutron absorber was synthesized by ball milling and sintering. Microstructure character of ball-milled Tb4O7-17.605%TiO2 (mass fraction, %) powders and sintered bulks was analyzed using XRD, SEM and TEM. The microhardness, coefficient of thermal expansion and thermal conductivity of sintered bulks were measured. The experiment results showed that the nanocrystalline solid solution was obtained during ball milling. After 96 h of ball milling, TiO2 was completely solved in Tb4O7 and the crystal size of Tb4O7 was up to 37 nm. The bulk materials prepared by cold isostatic pressing were sintered at 1300 °C. Tb2TiO5 bulks with an orthorhombic structure were obtained. The microhardness of sintered bulks, as well as the thermal conductivity, increased firstly with increasing ball milling time and then decreased. The coefficient of thermal expansion decreased initially and then increased with increasing ball milling time. For the sintered bulk with powder milled for 48 h, the highest values of both microhardness and thermal conductivity were observed, whereas the lowest coefficient of thermal expansion was exhibited. In addition, with increasing testing temperature, the thermal conductivity of sintered bulks initially fell and then rebounded while an opposite trend was found in the coefficient of thermal expansion.

  4. Microstructure and Physical Properties of Tb2TiO5 Neutron Absorber Synthesized by Ball Milling and Sintering

    Science.gov (United States)

    Huang, Jinghua; Ran, Guang; Liu, Tengjiao; Shen, Qiang; Li, Ning

    2016-10-01

    Tb2TiO5 neutron absorber was synthesized by ball milling and sintering. Microstructure character of ball-milled Tb4O7-17.605%TiO2 (mass fraction, %) powders and sintered bulks was analyzed using XRD, SEM and TEM. The microhardness, coefficient of thermal expansion and thermal conductivity of sintered bulks were measured. The experiment results showed that the nanocrystalline solid solution was obtained during ball milling. After 96 h of ball milling, TiO2 was completely solved in Tb4O7 and the crystal size of Tb4O7 was up to 37 nm. The bulk materials prepared by cold isostatic pressing were sintered at 1300 °C. Tb2TiO5 bulks with an orthorhombic structure were obtained. The microhardness of sintered bulks, as well as the thermal conductivity, increased firstly with increasing ball milling time and then decreased. The coefficient of thermal expansion decreased initially and then increased with increasing ball milling time. For the sintered bulk with powder milled for 48 h, the highest values of both microhardness and thermal conductivity were observed, whereas the lowest coefficient of thermal expansion was exhibited. In addition, with increasing testing temperature, the thermal conductivity of sintered bulks initially fell and then rebounded while an opposite trend was found in the coefficient of thermal expansion.

  5. Joint Acoustic and Modulation Frequency

    Directory of Open Access Journals (Sweden)

    Les Atlas

    2003-06-01

    Full Text Available There is a considerable evidence that our perception of sound uses important features which is related to underlying signal modulations. This topic has been studied extensively via perceptual experiments, yet there are few, if any, well-developed signal processing methods which capitalize on or model these effects. We begin by summarizing evidence of the importance of modulation representations from psychophysical, physiological, and other sources. The concept of a two-dimensional joint acoustic and modulation frequency representation is proposed. A simple single sinusoidal amplitude modulator of a sinusoidal carrier is then used to illustrate properties of an unconstrained and ideal joint representation. Added constraints are required to remove or reduce undesired interference terms and to provide invertibility. It is then noted that the constraints would also apply to more general and complex cases of broader modulation and carriers. Applications in single-channel speaker separation and in audio coding are used to illustrate the applicability of this joint representation. Other applications in signal analysis and filtering are suggested.

  6. High-Performance Ball Bearing

    Science.gov (United States)

    Bursey, Roger W., Jr.; Haluck, David A.; Olinger, John B.; Owen, Samuel S.; Poole, William E.

    1995-01-01

    High-performance bearing features strong, lightweight, self-lubricating cage with self-lubricating liners in ball apertures. Designed to operate at high speed (tens of thousands of revolutions per minute) in cryogenic environment like liquid-oxygen or liquid-hydrogen turbopump. Includes inner race, outer race, and cage keeping bearing balls equally spaced.

  7. Adolescent obesity, joint pain, and hypermobility

    OpenAIRE

    Bout-Tabaku, Sharon; Klieger, Sarah B; Wrotniak, Brian H; Sherry, David D; Zemel, Babette S; Stettler, Nicolas

    2014-01-01

    Background Obesity associated with joint pain of the lower extremities is likely due to excessive mechanical load on weight bearing joints. Additional mechanical factors may explain the association between obesity and joint pain. Findings We characterized the association between obesity and non-traumatic lower extremity (LE) joint pain in adolescents and examined the modifying effect of hypermobility on this association. We performed a cross-sectional analysis of data from subjects enrolled i...

  8. Porovnanie efektivity technológií WebSocket a AJAX pri implementácii kolaboratívneho editoru

    OpenAIRE

    Augustín, Jakub

    2012-01-01

    This thesis introduces modern web technology WebSocket that was designed to improve real-time communication. Websocket usage is described from both, server and client sides. This thesis should point out benefits of using WebSocket through the collaborative editor implementation. Application ICE, that is practical part of this thesis, shows real-world WebSocket implementation. Also, this thesis lists some of the most widely used techniques for real-time communication. AJAX is currently the mos...

  9. 46 CFR 154.524 - Piping joints: Welded and screwed couplings.

    Science.gov (United States)

    2010-10-01

    ... temperature of −55 °C (−67 °F), or warmer. (c) A socket weld fitting with attachment welds is allowed for pipe... warmer. (d) Screwed couplings are allowed for instrumentation and control piping that meets §...

  10. Search for strange quark matter and Q-balls with the SLIM experiment

    Energy Technology Data Exchange (ETDEWEB)

    Sahnoun, Z., E-mail: sahnoun@bo.infn.i [INFN Sez. Bologna, 40127 Bologna (Italy); Astrophysics Department, CRAAG, BP 63 Bouzareah, 16340 Algiers (Algeria)

    2009-10-15

    We report on the search for Strange Quark Matter (SQM) and charged Q-balls with the SLIM experiment at the Chacaltaya High Altitude Laboratory (5230 m a.s.l.) from 2001 to 2005. The SLIM experiment was a 427 m{sup 2} array of Nuclear Track Detectors (NTDs) arranged in modules of 24 x 24 cm{sup 2} area. SLIM NTDs were exposed to the cosmic radiation for 4.22 years after which they were brought back to the Bologna Laboratory where they were etched and analyzed. We estimate the properties and energy losses in matter of nuclearites (large SQM nuggets), strangelets (small charged SQM nuggets) and Q-balls; and discuss their detection with the SLIM experiment. The flux upper limits in the CR of such downgoing particles are at the level of 1.3 x 10{sup -15} cm{sup -2} s{sup -1} sr{sup -1} (90% CL).

  11. Search for strange quark matter and Q-balls with the SLIM experiment

    CERN Document Server

    Sahnoun, Z

    2008-01-01

    We report on the search for Strange Quark Matter (SQM) and charged Q-balls with the SLIM experiment at the Chacaltaya High Altitude Laboratory (5230 m a.s.l.) from 2001 to 2005. The SLIM experiment was a 427 m$^{2}$ array of Nuclear Track Detectors (NTDs) arranged in modules of $24 \\times 24$ cm$^{2}$ area. SLIM NTDs were exposed to the cosmic radiation for 4.22 years after which they were brought back to the Bologna Laboratory where they were etched and analyzed. We estimate the properties and energy losses in matter of nuclearites (large SQM nuggets), strangelets (small charged SQM nuggets) and Q-balls; and discuss their detection with the SLIM experiment. The flux upper limits in the CR of such downgoing particles are at the level of $1.3 10^{-15}$/cm$^{2}$/s/sr (90% CL).

  12. Position Prediction of Ball and Fuzzy Controller for Shooting Action in A Soccer Robot System

    OpenAIRE

    Ryang, GyongIl; Choe, MyongSong; Sin, YongChol

    2016-01-01

    The robot soccer game based complex motion control has been widely studied for the moving object capture and shooting. A position prediction algorithm based on global vision is introduced in order to improve the accuracy and robustness of the vision system for tracking moving objects, including a Kalmanfiter, a dynamic window and an obstacle avoidance strategy. This paper deals with the positon prediction for moving ball by using Kalmanfiter and the Fuzzy Controller for shooting action in a d...

  13. Norm equivalence and composition operators between Bloch/Lipschitz spaces of the ball

    OpenAIRE

    Stević Stevo; Clahane Dana D

    2006-01-01

    For , let and denote, respectively, the -Bloch and holomorphic -Lipschitz spaces of the open unit ball in . It is known that and are equal as sets when . We prove that these spaces are additionally norm-equivalent, thus extending known results for and the polydisk. As an application, we generalize work by Madigan on the disk by investigating boundedness of the composition operator from to .

  14. An analytical and numerical study of chaotic dynamics in a simple bouncing ball model

    Institute of Scientific and Technical Information of China (English)

    Andrzej Okninski; Boguslaw Radziszewski

    2011-01-01

    Dynamics of a ball moving in gravitational field and colliding with a moving table is studied in this paper.The motion of the limiter is assumed as periodic with piecewise constant velocity-it is assumed that the table moves up with a constant velocity and then moves down with another constant velocity. The Poincaré map, describing evolution from an impact to the next impact, is derived and scenarios of transition to chaotic dynamics are investigated analytically and numerically.

  15. On diagnosis measurement under dynamic loading of ball bearing using numerical thermal analysis and infrared thermography

    International Nuclear Information System (INIS)

    With the modern machinery towards the direction of high-speed development, the thermal issues of mechanical transmission system and its components is increasingly important. Ball bearing is one of the main parts in rotating machinery system, and is a more easily damaged part. In this paper, bearing thermal fault detection is investigated in details Using infrared thermal imaging technology to the operation state of the ball bearing, a preliminary thermal analysis, and the use of numerical simulation technology by finite element method(FEM) under thermal conditions of the bearing temperature field analysis, initially identified through these two technical analysis, bearing a temperature distribution in the normal state and failure state. It also shows the reliability of the infrared thermal imaging technology with valuable suggestions for the future bearing fault detection.

  16. Reconstruction of craniofacial image using rational cubic Ball interpolant and soft computing technique

    Science.gov (United States)

    Majeed, Abdul; Piah, Abd Rahni Mt

    2015-10-01

    Spline has been used extensively in engineering design and modelling for representation, analysis and manufacturing purposes. This paper presents an application of spline methods in bio-medical modelling. We reconstruct craniofacial fractured skull bone images using rational cubic Ball interpolant with two free parameters. The free parameters are optimized with the help of genetic algorithm. Our emphasis is placed on the accuracy and smoothness of the reconstructed images.

  17. Break-up Process of Perturbed Molten Metal Jet and Preparation of Lead-Free Solder Balls

    Institute of Scientific and Technical Information of China (English)

    He Lijun; Zhang Shuguang; Zhang Shaoming; Xu Jun; Shi Likai

    2004-01-01

    Solder balls, which are used in advanced electronics packages such as BGA (Ball Grid Array) and CSP (Chip Scale Package) to substitute the leads and realize the electrical and mechanical connections between substrate and chip,have severe specifications in diameter tolerance, roundness and surface quality, and therefore challenge the traditional technologies for fabrication of metallic particles and powders. The present work made a survey of perturbed molten metal jet break-up process, observed the formation and growth of capillary wave of tin-lead melt jet by way of rapid solidification, and on the basis of the above research, successfully obtained tin-lead eutectic and Sn-4.0Ag-0.5Cu lead free solder balls with tight distribution and good sphericity of particles through optimization of processing parameters, forming a solid base for cost effectively producing solder balls.

  18. Charged Q-ball dark matter from B and L direction

    Science.gov (United States)

    Hong, Jeong-Pyong; Kawasaki, Masahiro; Yamada, Masaki

    2016-08-01

    We consider nearly equal number of gauge mediation type charged (anti-) Q-balls with charge of ±α-1 simeq ±137 well before the BBN epoch and discussed how they evolve in time. We found that ion-like objects with electric charges of +O(1) are likely to become relics in the present universe, which we expect to be the dark matter. These are constrained by MICA experiment, where the trail of heavy atom-like or ion-like object in 109 years old ancient mica crystals is not observed. We found that the allowed region for gauge mediation model parameter and reheating temperature have to be smaller than the case of the neutral Q-ball dark matter.

  19. Charged Q-ball Dark Matter from $B$ and $L$ direction

    CERN Document Server

    Hong, Jeong-Pyong; Yamada, Masaki

    2016-01-01

    We consider nearly equal number of gauge mediation type charged (anti-) Q-balls with charge of $\\alpha^{-1}\\simeq137$ well before the BBN epoch and discussed how they evolve in time. We found that ion-like objects with electric charges of $+O(1)$ are likely to become relics in the present universe, which we expect to be the dark matter. These are constrained by MICA experiment, where the trail of heavy atom-like or ion-like object in $10^9$ years old ancient mica crystals is not observed. We found that the allowed region for gauge mediation model parameter and reheating temperature have to be smaller than the case of the neutral Q-ball dark matter.

  20. Detection and Identification of Fungi from Fungus Balls of the Maxillary Sinus by Molecular Techniques

    OpenAIRE

    Willinger, Birgit; Obradovic, Alexandra; Selitsch, Brigitte; Beck-Mannagetta, Johann; Buzina, Walter; Braun, Hannes; Apfalter, Petra; Hirschl, Alexander M.; Makristathis, Athanasios; Rotter, Manfred

    2003-01-01

    The aim of this study was to find a reliable method for the detection and identification of fungi in fungus balls of the maxillary sinus and to evaluate the spectrum of fungi in these samples. One hundred twelve samples were obtained from patients with histologically proven fungal infections; 81 samples were paraffin-embedded tissue sections of the maxillary sinus. In 31 cases, sinus contents without paraffin embedding were sent for investigation. PCR amplification with universal fungal prime...

  1. Prediction of tar ball formation

    Energy Technology Data Exchange (ETDEWEB)

    Khelifa, A.; Gamble, L. [Environment Canada, Ottawa, ON (Canada). Emergencies Science and Technology Division, Environmental Technology Centre, Science and Technology Branch

    2006-07-01

    The presence of small tar balls ranging in size from less than a millimetre to 60 centimetres have been observed during cleanup assessment operations following accidental oil spills on water. The tar balls are composed of heavy oil residues and suspended particulate matter (SPM) from the water column. They can be found on shorelines, settled on the seafloor and floating at or near the water surface. Their abundance on the shorelines varies from site to site and depends on the conditions of the spill and mixing conditions. Aggregation between SPM and micro-sized oil droplets occurs naturally in coastal waters and enhances the dispersion of spilled oil. Although tar balls are among the important end states of spilled oil in the marine environment, no model exists to estimate the percentage of the spilled oil that becomes tar balls. This paper offered some insight into the modeling of tar ball formation. Current modeling understanding of oil-SPM aggregate formation was used to predict tar ball formation. The formation of oil droplets was examined with respect to a range of conditions under which the formation of large droplets is expected. The role of aggregation was then presented to demonstrate the effects of concentration and type of SPM on the buoyancy of tar balls. Good agreement was found between modeling results and field data reported in the literature regarding the size and density of tar balls. Oil viscosity and mixing energy were found to be the main factors controlling the formation of tar balls. The aggregation of tar balls with SPM and shoreline material results in significant increases or decreases in density, depending on the type and concentration of SPM. 42 refs., 2 tabs., 6 figs.

  2. Research on Quality Inspection and Sorting On-line System for Bearing Steel Ball

    Directory of Open Access Journals (Sweden)

    Yu Runxiang

    2015-01-01

    Full Text Available To detect the flaws of bearing steel ball and sort its quality on-line, a kind of online quality detecting and sorting system for bearing steel ball is developed, which based on the eddy current inspection theory. The design of scheme, circuit and mechanical structure of the system is described in detail. PSD(Phase Sensitive Detection is applied to pick up the signal of cracks and restrain interferential signal. The flaws will be quantificational analysed based on the X-R orthogonal decomposition technology which include the size and depth information of flaws. By analysing and processing the amplitude and phase of the defect signal, the flaws can be found with high accuracy and low error-detected ratio. ARM and MCU Processor ensures the real-time ability of discriminating algorithm. The CPLD is used for generating reference signal which can be easy to get synchronous with the source signal. It has good properties of real-time to detect the quality of bearing steel ball.

  3. Microstructure and martensitic transformation in Si-coated TiNi powders prepared by ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae-hyun; Cho, Gyu-bong; Im, Yeon-min [School of Materials Science and Engineering, Gyeongsang National University, 900 Gazwadong, Jinju, Gyeongnam 660-701 (Korea, Republic of); Chun, Byong-sun [ReSEAT Program, KISTI, Daejeon 305-806 (Korea, Republic of); Kim, Yeon-wook [Department of Advanced Materials Engineering, Keimyung University, 1000 Shindang-dong, Dalseo-gu, Daegu 704-701 (Korea, Republic of); Nam, Tae-hyun, E-mail: tahynam@gnu.ac.kr [School of Materials Science and Engineering, Gyeongsang National University, 900 Gazwadong, Jinju, Gyeongnam 660-701 (Korea, Republic of)

    2013-12-15

    Graphical abstract: - Highlights: • Amorphous Si-coated TiNi powders were prepared successfully by ball milling. • Ti{sub 4}Ni{sub 4}Si{sub 7} was formed at the interface between Si and TiNi after annealing. • Si-coated Ti–Ni powders displayed the R phase after annealing. - Abstract: Si was coated on the surface of Ti–49Ni (at%) alloy powders by ball milling in order to improve the electrochemical properties of the Si electrodes of secondary Li ion batteries and then the microstructure and martensitic transformation behavior were investigated by means of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Ti–Ni powders coated with Si were fabricated successfully by ball milling. As-milled powders consisted of highly deformed Ti–Ni powders with the B2 phase and amorphous Si layers. The thickness of the Si layer coated on the surface of the Ti–Ni powders increased from 3–5 μm to 10–15 μm by extending the milling time from 3 h to 48 h. However, severe contamination from the grinding media, ZrO{sub 2} occurred when the ball milling time was as long as 48 h. By heating as-milled powders to various temperatures in the range of 673–873 K, the highly deformed Ti–Ni powders were recovered and Ti{sub 4}Ni{sub 4}Si{sub 7} was formed. Two-stage B2–R–B19′ transformation occurred when as-milled Si-coated Ti–49Ni alloy powders were heated to temperatures below 873 K, above this temperature one-stage B2–B19′ transformation occurred.

  4. Cosmological phase transition, baryon asymmetry and dark matter Q-balls

    CERN Document Server

    Krylov, E; Rubakov, V

    2013-01-01

    We consider a mechanism of dark matter production in the course of first order phase transition. We assume that there is an asymmetry between X- and anti-X-particles of dark sector. In particular, it may be related to the baryon asymmetry. We also assume that the phase transition is so strongly first order, that X-particles do not permeate into the new phase. In this case, as the bubbles of old phase collapse, X-particles are packed into Q-balls with huge mass defect. These Q-balls compose the present dark matter. We find that the required present dark matter density is obtained for the energy scale of the theory in the ballpark of 1-10 TeV. As an example we consider a theory with effective potential of one-loop motivated form.

  5. Nonlinear control via approximate input-output linearization - The ball and beam example

    Science.gov (United States)

    Hauser, John; Sastry, Shankar; Kokotovic, Petar

    1992-01-01

    A study is made of approximate input-output linearization of nonlinear systems which fail to have a well defined relative degree. For such systems, a method is provided for constructing approximate systems that are input-output linearizable. The analysis presented in this note is motivated through its application to a common undergraduate control laboratory experiment, the ball and beam system, where it is shown to be more effective for trajectory tracking than the standard Jacobian linearization.

  6. RESEARCH ABOUT RESULTS REPRODUTIBILITY AND ABRASIVE PARTICLES FRAGMENTATION IN BALL-CRATERING TESTS

    Directory of Open Access Journals (Sweden)

    Ronaldo Câmara Cozza

    2013-06-01

    Full Text Available The micro-abrasive wear tests by rotating ball (crater wear have played an important role in abrasive wear researches. In this type of test, the contact between a specimen and a ball on rotating motion and abrasive particles supplied between these two elements, results in a crater on the specimen, based on which the abrasive wear behaviour is analysed. The purpose of this work is to study results the reprodutibility and the silicon carbide (SiC abrasive particles fragmentation during micro-abrasive wear tests. Tests were conducted with carburized AISI 1010 steel balls and high speed steel specimens, “with” and “without” titanium nitride (TiN coatings. The abrasive slurry was prepared with black silicon carbide (average particle size of 5 µm and distilled water. Grooving abrasion is related with lower reprodutibility results. For the test conditions of this work, no abrasive particles fragmentation was observed, independently of the sliding distance, what is justified, among others factors, by the low normal force applied.

  7. Effect of prosthetic alignment changes on socket reaction moment impulse during walking in transtibial amputees.

    Science.gov (United States)

    Kobayashi, Toshiki; Orendurff, Michael S; Arabian, Adam K; Rosenbaum-Chou, Teri G; Boone, David A

    2014-04-11

    The alignment of a lower limb prosthesis affects the way load is transferred to the residual limb through the socket, and this load is critically important for the comfort and function of the prosthesis. Both magnitude and duration of the moment are important factors that may affect the residual limb health. Moment impulse is a well-accepted measurement that incorporates both factors via moment-time integrals. The aim of this study was to investigate the effect of alignment changes on the socket reaction moment impulse in transtibial prostheses. Ten amputees with transtibial prostheses participated in this study. The socket reaction moment impulse was measured at a self-selected walking speed using a Smart Pyramid in 25 alignment conditions, including a nominal alignment (clinically aligned by a prosthetist), as well as angle malalignments of 2°, 4° and 6° (abduction, adduction, extension and flexion) and translation malalignments of 5 mm, 10 mm and 15 mm (lateral, medial, anterior and posterior). The socket reaction moment impulse of the nominal alignment was compared for each condition. The relationship between the alignment and the socket reaction moment impulse was clearly observed in the coronal angle, coronal translation and sagittal translation alignment changes. However, this relationship was not evident in the sagittal angle alignment changes. The results of this study suggested that the socket reaction moment impulse could potentially serve as a valuable parameter to assist the alignment tuning process for transtibial prostheses. Further study is needed to investigate the influence of the socket reaction moment impulse on the residual limb health.

  8. Stiffness matrix formulation for double row angular contact ball bearings: Analytical development and validation

    Science.gov (United States)

    Gunduz, Aydin; Singh, Rajendra

    2013-10-01

    Though double row angular contact ball bearings are widely used in industrial, automotive, and aircraft applications, the scientific literature on double row bearings is sparse. It is also shown that the stiffness matrices of two single row bearings may not be simply superposed to obtain the stiffness matrix of a double row bearing. To overcome the deficiency in the literature, a new, comprehensive, analytical approach is proposed based on the Hertzian theory for back-to-back, face-to-face, and tandem arrangements. The elements of the five-dimensional stiffness matrix for double row angular contact ball bearings are computed given either the mean bearing displacement or the mean load vector. The diagonal elements of the proposed stiffness matrix are verified with a commercial code for all arrangements under three loading scenarios. Some changes in stiffness coefficients are investigated by varying critical kinematic and geometric parameters to provide more insight. Finally, the calculated natural frequencies of a shaft-bearing experiment are successfully compared with measurements, thus validating the proposed stiffness formulation. For double row angular contact ball bearings, the moment stiffness and cross-coupling stiffness terms are significant, and the contact angle changes under loads. The proposed formulation is also valid for paired (duplex) bearings which behave as an integrated double row unit when the surrounding structural elements are sufficiently rigid.

  9. Magnetoresistivity and microstructure of YBa2Cu3Oy prepared using planetary ball milling

    Science.gov (United States)

    Hamrita, A.; Ben Azzouz, F.; Madani, A.; Ben Salem, M.

    2012-01-01

    We have studied the microstructure and the magnetoresistivity of polycrystalline YBa2Cu3Oy (YBCO or Y-123 for brevity) embedded with nanoparticles of Y-deficient YBCO, generated by the planetary ball milling technique. Bulk samples were synthesized from a precursor YBCO powder, which was prepared from commercial high purity Y2O3, Ba2CO3 and CuO via a one-step annealing process in air at 950 °C. After planetary ball milling of the precursor, the powder was uniaxially pressed and subsequently annealed at 950 °C in air. Phase analysis by X-ray diffraction (XRD), granular structure examination by scanning electron microscopy (SEM), microstructure investigation by transmission electron microscopy (TEM) coupled with energy dispersive X-ray spectroscopy (EDXS) were carried out. TEM analyses show that nanoparticles of Y-deficient YBCO, generated by ball milling, are embedded in the superconducting matrix. Electrical resistance as a function of temperature, ρ(T), revealed that the zero resistance temperature, Tco, is 84.5 and 90 K for the milled and unmilled samples respectively. The milled ceramics exhibit a large magnetoresistance in weak magnetic fields at liquid nitrogen temperature. This attractive effect is of high significance as it makes these materials promising candidates for practical application in magnetic field sensor devices.

  10. Silicon Nitride Balls For Cryogenic Bearings

    Science.gov (United States)

    Butner, Myles F.; Ng, Lillian W.

    1990-01-01

    Resistance to wear greater than that of 440C steel. Experiments show lives of ball bearings immersed in liquid nitrogen or liquid oxygen increased significantly when 440C steel balls (running on 440C steel races) replaced by balls of silicon nitride. Developed for use at high temperatures, where lubrication poor or nonexistent. Best wear life of any bearing tested to date and ball material spalls without fracturing. Plans for future tests call for use of liquid oxygen as working fluid.

  11. Application of the Blobo bluetooth ball in wrist rehabilitation training.

    Science.gov (United States)

    Hsieh, Wei-Min; Hwang, Yuh-Shyan; Chen, Shih-Ching; Tan, Sun-Yen; Chen, Chih-Chen; Chen, Yu-Luen

    2016-01-01

    [Purpose] The introduction of emerging technologies such as the wireless Blobo bluetooth ball with multimedia features can enhance wrist physical therapy training, making it more fun and enhancing its effects. [Methods] Wrist injuries caused by fatigue at work, improper exercise, and other conditions are very common. Therefore, the reconstruction of wrist joint function is an important issue. The efficacy of a newly developed integrated wrist joint rehabilitation game using a Blobo bluetooth ball with C# software installed was tested in wrist rehabilitation (Flexion, Extension, Ulnar Deviation, Radial Deviation). [Results] Eight subjects with normal wrist function participated in a test of the system's stability and repeatability. After performing the Blobo bluetooth ball wrist physical therapy training, eight patients with wrist dysfunction experienced approximately 10° improvements in range of motion (ROM) of flexion extension, and ulnar deviation and about 6° ROM improvement in radial deviation. The subjects showed progress in important indicators of wrist function. [Conclusion] This study used the Blobo bluetooth ball in wrist physical therapy training and the preliminary results were encouraging. In the future, more diverse wrist or limb rehabilitation games should be developed to meet the needs of physical therapy training. PMID:26957723

  12. Seismic response of rock joints and jointed rock mass

    International Nuclear Information System (INIS)

    Long-term stability of emplacement drifts and potential near-field fluid flow resulting from coupled effects are among the concerns for safe disposal of high-level nuclear waste (HLW). A number of factors can induce drift instability or change the near-field flow patterns. Repetitive seismic loads from earthquakes and thermal loads generated by the decay of emplaced waste are two significant factors. One of two key technical uncertainties (KTU) that can potentially pose a high risk of noncompliance with the performance objectives of 10 CFR Part 60 is the prediction of thermal-mechanical (including repetitive seismic load) effects on stability of emplacement drifts and the engineered barrier system. The second KTU of concern is the prediction of thermal-mechanical-hydrological (including repetitive seismic load) effects on the host rock surrounding the engineered barrier system. The Rock Mechanics research project being conducted at the Center for Nuclear Waste Regulatory Analyses (CNWRA) is intended to address certain specific technical issues associated with these two KTUs. This research project has two major components: (i) seismic response of rock joints and a jointed rock mass and (ii) coupled thermal-mechanical-hydrological (TMH) response of a jointed rock mass surrounding the engineered barrier system (EBS). This final report summarizes the research activities concerned with the repetitive seismic load aspect of both these KTUs

  13. Seismic response of rock joints and jointed rock mass

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, A.; Hsiung, S.M.; Chowdhury, A.H. [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses

    1996-06-01

    Long-term stability of emplacement drifts and potential near-field fluid flow resulting from coupled effects are among the concerns for safe disposal of high-level nuclear waste (HLW). A number of factors can induce drift instability or change the near-field flow patterns. Repetitive seismic loads from earthquakes and thermal loads generated by the decay of emplaced waste are two significant factors. One of two key technical uncertainties (KTU) that can potentially pose a high risk of noncompliance with the performance objectives of 10 CFR Part 60 is the prediction of thermal-mechanical (including repetitive seismic load) effects on stability of emplacement drifts and the engineered barrier system. The second KTU of concern is the prediction of thermal-mechanical-hydrological (including repetitive seismic load) effects on the host rock surrounding the engineered barrier system. The Rock Mechanics research project being conducted at the Center for Nuclear Waste Regulatory Analyses (CNWRA) is intended to address certain specific technical issues associated with these two KTUs. This research project has two major components: (i) seismic response of rock joints and a jointed rock mass and (ii) coupled thermal-mechanical-hydrological (TMH) response of a jointed rock mass surrounding the engineered barrier system (EBS). This final report summarizes the research activities concerned with the repetitive seismic load aspect of both these KTUs.

  14. Have a Ball

    Institute of Scientific and Technical Information of China (English)

    程炜

    2003-01-01

    Before being sent to prison Carl drove big cars and ate in expensive restaurants. No one knew where he got his money but he was certainly having a ball. When the judge sentenced him.to prison he said, “I hope you have a bail, Carl.” To have a bait is to have a wonderful time.

  15. Influences of the G2350A polymorphism in the ACE Gene on cardiac structure and function of ball game players

    Directory of Open Access Journals (Sweden)

    Jang Yongwoo

    2012-01-01

    Full Text Available Abstract Background Except for the I/D polymorphism in the angiotensin I-converting enzyme (ACE gene, there were few reports about the relationship between other genetic polymorphisms in this gene and the changes in cardiac structure and function of athletes. Thus, we investigated whether the G2350A polymorphism in the ACE gene is associated with the changes in cardiac structure and function of ball game players. Total 85 healthy ball game players were recruited in this study, and they were composed of 35 controls and 50 ball game players, respectively. Cardiac structure and function were measured by 2-D echocardiography, and the G2350A polymorphism in the ACE gene analyzed by the SNaPshot method. Results There were significant differences in left ventricular mass index (LVmassI value among each sporting discipline studied. Especially in the athletes of basketball disciplines, indicated the highest LVmassI value than those of other sporting disciplines studied (p ACE gene in the both controls and ball game players. Conclusions Our data suggests that the G2350A polymorphism in the ACE gene may not significantly contribute to the changes in cardiac structure and function of ball game players, although sporting disciplines of ball game players may influence the changes in LVmassI value of these athletes. Further studies using a larger sample size and other genetic markers in the ACE gene will be needed.

  16. Books and Balls: Antecedents and Outcomes of College Identification

    Science.gov (United States)

    Porter, Thomas; Hartman, Katherine; Johnson, John Seth

    2011-01-01

    Identification plays a central role in models of giving to an organization. This study presents and tests a general model of giving that highlights status based and affect based drivers of identification. The model was tested using a sample of 114 alumni from 74 different colleges participated in an online survey. Identification was found to…

  17. Experimental Analysis of Damping and Tribological Characteristics of Nano-CuO Particle Mixed Lubricant in Ball Bearings

    Science.gov (United States)

    Prakash, E.; Sivakumar, K.

    2015-12-01

    Experimental analysis of damping capacity and tribological characteristics of nano CuO added Servosystem 68 lubricant is attempted. CuO nano particles were synthesized by aqueous precipitation method and characterized. Prior to dispersion into lubricant, CuO nano particles were coated with 0.2 wt.% surfactant (Span-80) to stabilize the nano fluid. Tribological characteristics of particle added lubricant were tested in ASTM D 4172 four ball wear tester. Scanning electron microscopy test results of worn surfaces of nano CuO particle added lubricant were smoother than base lubricant. The particle added lubricant was applied in a new ball bearing and three defected ball bearings. When particle added lubricant was used, the ball defected bearing's vibration amplitude was reduced by 21.94% whereas it was 16.46% for new bearing and was ≤ 11% for other defected bearings. The formation of protection film of CuO over ball surface and regime of full film lubrication near the ball zone were observed to be reason for improved damping of vibrations.

  18. Detection of Prosthetic Knee Movement Phases via In-Socket Sensors: A Feasibility Study.

    Science.gov (United States)

    El-Sayed, Amr M; Hamzaid, Nur Azah; Tan, Kenneth Y S; Abu Osman, Noor Azuan

    2015-01-01

    This paper presents an approach of identifying prosthetic knee movements through pattern recognition of mechanical responses at the internal socket's wall. A quadrilateral double socket was custom made and instrumented with two force sensing resistors (FSR) attached to specific anterior and posterior sites of the socket's wall. A second setup was established by attaching three piezoelectric sensors at the anterior distal, anterior proximal, and posterior sites. Gait cycle and locomotion movements such as stair ascent and sit to stand were adopted to characterize the validity of the technique. FSR and piezoelectric outputs were measured with reference to the knee angle during each phase. Piezoelectric sensors could identify the movement of midswing and terminal swing, pre-full standing, pull-up at gait, sit to stand, and stair ascent. In contrast, FSR could estimate the gait cycle stance and swing phases and identify the pre-full standing at sit to stand. FSR showed less variation during sit to stand and stair ascent to sensitively represent the different movement states. The study highlighted the capacity of using in-socket sensors for knee movement identification. In addition, it validated the efficacy of the system and warrants further investigation with more amputee subjects and different sockets types.

  19. Ball assisted device for analytical surface sampling

    Science.gov (United States)

    ElNaggar, Mariam S; Van Berkel, Gary J; Covey, Thomas R

    2015-11-03

    A system for sampling a surface includes a sampling probe having a housing and a socket, and a rolling sampling sphere within the socket. The housing has a sampling fluid supply conduit and a sampling fluid exhaust conduit. The sampling fluid supply conduit supplies sampling fluid to the sampling sphere. The sampling fluid exhaust conduit has an inlet opening for receiving sampling fluid carried from the surface by the sampling sphere. A surface sampling probe and a method for sampling a surface are also disclosed.

  20. Aerodynamics of a golf ball with grooves

    Science.gov (United States)

    Kim, Jooha; Son, Kwangmin; Choi, Haecheon

    2009-11-01

    It is well known that the drag on a dimpled ball is much lower than that on smooth ball. Choi et al. (Phys. Fluids, 2006) showed that turbulence is generated through the instability of shear layer separating from the edge of dimples and delays flow separation. Based on this mechanism, we devise a new golf ball with grooves on the surface but without any dimples. To investigate the aerodynamic performance of this new golf ball, an experiment is conducted in a wind tunnel at the Reynolds numbers of 0.5 x10^5 - 2.7 x10^5 and the spin ratios (ratio of surface velocity to the free-stream velocity) of α=0 - 0.5, which are within the ranges of real golf-ball velocity and spin rate. We measure the drag and lift forces on the grooved ball and compare them with those of smooth ball. At zero spin, the drag coefficient on the grooved ball shows a rapid fall-off at a critical Reynolds number and maintains a minimum value which is lower by 50% than that on smooth ball. At non-zero α, the drag coefficient on the grooved ball increases with increasing α, but is still lower by 40% than that on smooth ball. The lift coefficient on the grooved ball increases with increasing α, and is 100% larger than that on smooth ball. The aerodynamic characteristics of grooved ball is in general quite similar to that of dimpled ball. Some more details will be discussed in the presentation.

  1. Effect of irradiation on the healing of extraction sockets in diabetic rats

    International Nuclear Information System (INIS)

    To observe the histologic pattern of healing in molar tooth extraction sockets of streptozotocin-induced diabetic rats following irradiation. Mature Sprague-Dawley rats were divided into three groups: control, diabetic, and diabetic-irradiated groups. Diabetes mellitus was induced by injecting streptozotocin. Control rats were injected with a citrate buffer only. After 5 days, the right maxillary first molar was extracted under general anesthesia from each of the rats. After the extraction, rats in the diabetic-irradiated group were irradiated with a single absorbed dose of 10 Gy to the head and neck region. The rats were killed at 1, 3, 7, 14, 21, and 28 days after treatment. Tissue sections were stained with hematoxylin-eosin and Masson's trichrome. In the diabetic and diabetic-irradiated groups, the early healing process of the socket extraction was similar to the control group, but bone formation was delayed at 7 days after the treatment. In the diabetic-irradiated group, alveolar bone surrounding the extraction socket showed sighs of necrosis at 3 days after treatment, and hemorrhage was observed in connective tissue within the extraction socket at 14 days after treatment. The experiment revealed that the healing process of the extraction socket was severely delayed and retarded by irradiation in the diabetic state.

  2. Effect of irradiation on the healing of extraction sockets in diabetic rats

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Il Joong; Hwang, Eui Hwan; Lee, Sang Rae [Kyunghee University College of Medicine, Seoul (Korea, Republic of)

    2003-03-15

    To observe the histologic pattern of healing in molar tooth extraction sockets of streptozotocin-induced diabetic rats following irradiation. Mature Sprague-Dawley rats were divided into three groups: control, diabetic, and diabetic-irradiated groups. Diabetes mellitus was induced by injecting streptozotocin. Control rats were injected with a citrate buffer only. After 5 days, the right maxillary first molar was extracted under general anesthesia from each of the rats. After the extraction, rats in the diabetic-irradiated group were irradiated with a single absorbed dose of 10 Gy to the head and neck region. The rats were killed at 1, 3, 7, 14, 21, and 28 days after treatment. Tissue sections were stained with hematoxylin-eosin and Masson's trichrome. In the diabetic and diabetic-irradiated groups, the early healing process of the socket extraction was similar to the control group, but bone formation was delayed at 7 days after the treatment. In the diabetic-irradiated group, alveolar bone surrounding the extraction socket showed sighs of necrosis at 3 days after treatment, and hemorrhage was observed in connective tissue within the extraction socket at 14 days after treatment. The experiment revealed that the healing process of the extraction socket was severely delayed and retarded by irradiation in the diabetic state.

  3. An evaluation of computer aided design of below-knee prosthetic sockets.

    Science.gov (United States)

    Topper, A K; Fernie, G R

    1990-12-01

    Forty-eight below-knee amputees compared sockets designed using CANFIT computer aided design (CAD) software with sockets designed using conventional methods. Each subject was fitted by one prosthetist who used conventional techniques and one who used the CANFIT system to design the socket. Prosthetists alternated design methods for each new subject. The prosthetist using the conventional techniques was allowed up to 2 design attempts and the prosthetist using the CANFIT system was allowed up to 5 design attempts. After 2 design attempts with each method 21% of the subjects preferred the CANFIT design socket. Following up to 5 attempts 54% preferred the CANFIT designed socket. A jury of experts made an assessment of the CANFIT system and of CAD in prosthetics. The jury did not think that the version of the system tested was cost effective but that at the rate that it was improving it would become such within 3 to 5 years. The jury noted that, as well as monetary benefits, CAD presents the possibility of benefits in other areas such as research and teaching. A number of specific suggestions regarding the use and development of CAD in prosthetics were also made.

  4. Piezoelectric Bimorphs’ Characteristics as In-Socket Sensors for Transfemoral Amputees

    Directory of Open Access Journals (Sweden)

    Amr M. El-Sayed

    2014-12-01

    Full Text Available Alternative sensory systems for the development of prosthetic knees are being increasingly highlighted nowadays, due to the rapid advancements in the field of lower limb prosthetics. This study presents the use of piezoelectric bimorphs as in-socket sensors for transfemoral amputees. An Instron machine was used in the calibration procedure and the corresponding output data were further analyzed to determine the static and dynamic characteristics of the piezoelectric bimorph. The piezoelectric bimorph showed appropriate static operating range, repeatability, hysteresis, and frequency response for application in lower prosthesis, with a force range of 0–100 N. To further validate this finding, an experiment was conducted with a single transfemoral amputee subject to measure the stump/socket pressure using the piezoelectric bimorph embedded inside the socket. The results showed that a maximum interface pressure of about 27 kPa occurred at the anterior proximal site compared to the anterior distal and posterior sites, consistent with values published in other studies. This paper highlighted the capacity of piezoelectric bimorphs to perform as in-socket sensors for transfemoral amputees. However, further experiments are recommended to be conducted with different amputees with different socket types.

  5. Piezoelectric bimorphs' characteristics as in-socket sensors for transfemoral amputees.

    Science.gov (United States)

    El-Sayed, Amr M; Hamzaid, Nur Azah; Abu Osman, Noor Azuan

    2014-12-10

    Alternative sensory systems for the development of prosthetic knees are being increasingly highlighted nowadays, due to the rapid advancements in the field of lower limb prosthetics. This study presents the use of piezoelectric bimorphs as in-socket sensors for transfemoral amputees. An Instron machine was used in the calibration procedure and the corresponding output data were further analyzed to determine the static and dynamic characteristics of the piezoelectric bimorph. The piezoelectric bimorph showed appropriate static operating range, repeatability, hysteresis, and frequency response for application in lower prosthesis, with a force range of 0-100 N. To further validate this finding, an experiment was conducted with a single transfemoral amputee subject to measure the stump/socket pressure using the piezoelectric bimorph embedded inside the socket. The results showed that a maximum interface pressure of about 27 kPa occurred at the anterior proximal site compared to the anterior distal and posterior sites, consistent with values published in other studies. This paper highlighted the capacity of piezoelectric bimorphs to perform as in-socket sensors for transfemoral amputees. However, further experiments are recommended to be conducted with different amputees with different socket types.

  6. Simple Communication Based on SOCKET%基于SOCKET的简单通信

    Institute of Scientific and Technical Information of China (English)

    洪永新

    2014-01-01

    介绍了如何创建套接字,如何连接套接字以及如何共享数据,以便进行socket通信,主要是用Ruby编程语言进行创建的,而且并不是仅仅要是Ruby所提供的套接字API的包装类(wrap class),而是先讲解低层次的API。然后再介绍Ruby的包装类,使你对套接字的理解不仅仅局限在Ruby。%The article mainly introduces how to create a socket to socket,and how to share data,in order to carry out socket communication,is mainly used Rubyprogramming language was created,and not only if the socket API Ruby provided by the wrapper class (wrapclass),but to explain the lower level API.And thenintroduces the Ruby wrapper classes,enable you to the understanding of the socket is not limited in Ruby.

  7. On Implementation of Bidirectional Real-time Communication between Server and Browser Based on Socket.IO Framework%基于Socket.IO框架的服务器与浏览器双向实时通信的实现

    Institute of Scientific and Technical Information of China (English)

    陈希球

    2016-01-01

    Node.js是全球最受欢迎的Web应用开发平台,它采用模块式的开源框架结构,聚集了众多的开发资源,其中socket.io模块封装了网络底层通信,支持多种网络通信协议,易于实现跨浏览器通信.通过分析socket.io模块的通信功能,实现了服务器与浏览器之间的双向通信,并说明了编程方法.

  8. Coal-ball floras of maritime Canada and palynology of the Foord seam: geologic paleobotanical and paleoecogical implications

    Energy Technology Data Exchange (ETDEWEB)

    Lyons, P.C.; Zodrow, E.L.; Millay, M.A.; Dolby, G.; Gillis, K.S.; Cross, A.T. [US Geological Survey, Reston, VA (United States). National Center

    1997-01-01

    Coal balls in the Canadian Carboniferous System are known from the Clifton Formation (late Bolsovian) of New Brunswick and from the Foord seam (Stellarton Formation, late Bolsovian) of the Stellarton Basin of Nova Scotia. Coal balls from these two units are dominated by arborescent lycopods but ferns, seed ferns, calamiteans, and cordaiteans also occur. Baxter`s 1960 list of coal-ball plants from New Brunswick is updated. The palynomorphs and coal-ball plants of the Foord seam of the Stellarton Basin are illustrated and their paleoecology is discussed. Five genera of arborescent lycopods were present in the Foord swamp: Diaphorodendron, Paralycopodites, Lepidophloios, Sigillaria and Lepidodendron. The first three genera are represented in coal balls; the second two are also represented as compressions in the Foord seam; and all genera are represented in the spore assemblages from the Foord seam. The palynostratigraphy indicates that Sigillaria and Diaphorodendron were almost exclusively confined to the upper bench, whereas the other three genera were probably present in the Foord mire throughout its entire history. Palynomorphic changes in the Foord mire probably reflect gradual changes in wet and dry conditions.

  9. Reliability and standard market design : a square plug and a round socket, the fundamental flaw of the market design

    International Nuclear Information System (INIS)

    A electricity power system is designed and built to deliver reliable power supplies. A failure of a single component should not lead to the failure of the entire system. Oversupply results in prices at marginal cost of production, inadequate return on capital investment and economic failure of supplies. Uneconomic sources of supply would pull out in cases of oversupply. Competitive markets need flexible supply and demand and scarcity pricing in order to promote new investment. The problem with such a scenario is that scarcity reduces the level of reliability. An oversupply, while ensuring reliability, offers an inadequate return on capital. This presentation included several graphs depicting results of market failure with reference to NYMEX analysis of credit quality, NEPOOL summer capacity 2001, NYS summer capacity 2001, and PJM summer capacity 2001. A graph illustrating a New England 2002 load duration curve and its analysis was also included. According to the author, the market design is flawed because it does not pay for reliability. It fails to compensate generation for capital at risk, and it fails to address the fact that nearly half of the capacity supplies less than 10 per cent energy. He notes that the liquidity crisis will continue and grow unless changes are made and new entrants come into the market. 8 figs

  10. Effect of adding ball-milled achenes to must on bioactive compounds and antioxidant activities in fruit wine.

    Science.gov (United States)

    Lee, Pao-Ju; Chen, Shaun

    2016-03-01

    This study reports the utilization of ball-milled achenes in fermentation to increase the levels of ellagic acid and total phenol content, as well as to enhance the antioxidant capacity of strawberry wine. Achenes were micronized using ball-milling process, and then added to strawberry must prior to fermentation. The effects of the addition of ball-milled achenes on the ellagic acid and total phenol content in strawberry wine were determined, and the free radical scavenging and iron chelation activities were also analyzed. Quality attributes and acceptance were studied in comparison with a leading commercial strawberry wine for market application. The particle sizes of achenes were reduced from 1.1 mm to 400 nm after 30 min of ball-milling, and this led to an increase in the amount of extracted ellagic acid from 550.72 to 915.24 μg/g. The addition of ball-milled achenes to must led to a 19.72 % and 52.37 % increase in ellagic acid and total phenol content in strawberry wine, respectively. The increase in bioactive compounds resulted in increases of 54.09 %, 51.49 % and 56.97 % in ABTS and DPPH radical scavenging, and ferrous ion chelating activities, respectively. Although the commercial strawberry wine showed greater aroma intensity, no significant differences in overall quality and acceptance among the conventional process, added ball-milled achenes and the leading commercial strawberry wines were found. This study demonstrates that supplementation of ball-milled achenes in fermentation can be beneficial in increasing the levels of bioactive compounds and antioxidative capacity, indicating a good market potential. PMID:27570280

  11. The similarities between the hallucinations associated with the partial epileptic seizures of the occipital lobe and ball lightning observations

    Science.gov (United States)

    Cooray, G. K.; Cooray, V.

    2007-12-01

    Ball Lightning was seen and described since antiquity and recorded in many places. Ball lightning is usually observed during thunderstorms but large number of ball lightning observations is also reported during fine weather without any connection to thunderstorms or lightning. However, so far no one has managed to generate them in the laboratory. It is photographed very rarely and in many cases the authenticity of them is questionable. It is possible that many different phenomena are grouped together and categorized simply as ball lightning. Indeed, the visual hallucinations associated with simple partial epileptic seizures, during which the patient remains conscious, may also be categorized by a patient unaware of his or her condition as ball lightning observation. Such visual hallucinations may occur as a result of an epileptic seizure in the occipital, temporo-occipital or temporal lobes of the cerebrum [1,2,3]. In some cases the hallucination is perceived as a coloured ball moving horizontally from the periphery to the centre of the vision. The ball may appear to be rotating or spinning. The colour of the ball can be red, yellow, blue or green. Sometimes, the ball may appear to have a solid structure surrounded by a thin glow or in other cases the ball appears to generate spark like phenomena. When the ball is moving towards the centre of the vision it may increase its intensity and when it reaches the centre it can 'explode' illuminating the whole field of vision. During the hallucinations the vision is obscured only in the area occupied by the apparent object. The hallucinations may last for 5 to 30 seconds and rarely up to a minute. Occipital seizures may spread into other regions of the brain giving auditory, olfactory and sensory sensations. These sensations could be buzzing sounds, the smell of burning rubber, pain with thermal perception especially in the arms and the face, and numbness and tingling sensation. In some cases a person may experience only

  12. Joint denervation and neuroma surgery as joint-preserving therapy for ankle pain.

    Science.gov (United States)

    Gohritz, Andreas; Dellon, A Lee; Kalbermatten, Daniel; Fulco, Ilario; Tremp, Mathias; Schaefer, Dirk J

    2013-09-01

    Partial joint denervation or surgical neuroma therapy are alternative concepts to treat pain around the ankle joint that preserve joint function and relieve pain by interrupting neural pathways that transmit pain impulses from the joint to the brain. This review article summarizes the indication, anatomic background, operative techniques, and clinical results of joint denervation or neuroma surgery, which, although rarely reported and used, may provide a valuable alternative treatment in selected patients with neurogenous problems around the ankle. PMID:24008220

  13. Synthesis, characterization and gas sensing properties of novel homo and hetero dinuclear ball-type phthalocyanines.

    Science.gov (United States)

    Kakı, Esra; Altındal, Ahmet; Salih, Bekir; Bekaroğlu, Özer

    2015-05-01

    New ball-type homodinuclear Co(ii)-Co(ii) phthalocyanine () and ball-type heterodinuclear Co(ii)-Fe(ii) phthalocyanine () were synthesized from the corresponding [2,10,16,24-tetrakis{4,4'-cyclohexylidenebis(2-cyclohexyphenoxyphthalonitrile)}phthalocyaninatocobalt(ii)] (). The novel compounds have been characterized by elemental analysis, IR, UV-Vis and MALDI-TOF mass spectroscopy. Gas sensing capability of the spin coated film of and were studied using amperometric technique at various temperatures. For a better understanding of the interaction of and films with organic compounds, two different groups of compounds (aromatics and alcohols) were selected as test analytes. It was observed that the operating temperature had a considerable effect on the gas sensing performance of the sensors investigated. The experimental results show that film offers a promising perspective as a sensing material for the detection of relatively low aromatic vapours even at room temperature. This suggests that aromatics might be distinguished from alcohols. The obtained data were analysed using two different adsorption kinetic models: the pseudo first order equation and Elovich equation to determine the best fit equation for the adsorption of toluene vapor onto and films. The first-order equation was the best of the various kinetic models studied to describe the adsorption kinetic of toluene on Pc films at higher concentrations, as evidenced by the highest correlation coefficients. In addition, it was observed that Elovich equation generates a straight line that best fit to the data of adsorption of lower concentrations of toluene.

  14. The Transmission Interfaces Contribute Asymmetrically to the Assembly and Activity of Human P-glycoprotein.

    Science.gov (United States)

    Loo, Tip W; Clarke, David M

    2015-07-01

    P-glycoprotein (P-gp; ABCB1) is an ABC drug pump that protects us from toxic compounds. It is clinically important because it confers multidrug resistance. The homologous halves of P-gp each contain a transmembrane (TM) domain (TMD) with 6 TM segments followed by a nucleotide-binding domain (NBD). The drug- and ATP-binding sites reside at the interface between the TMDs and NBDs, respectively. Each NBD is connected to the TMDs by a transmission interface involving a pair of intracellular loops (ICLs) that form ball-and-socket joints. P-gp is different from CFTR (ABCC7) in that deleting NBD2 causes misprocessing of only P-gp. Therefore, NBD2 might be critical for stabilizing ICLs 2 and 3 that form a tetrahelix bundle at the NBD2 interface. Here we report that the NBD1 and NBD2 transmission interfaces in P-gp are asymmetric. Point mutations to 25 of 60 ICL2/ICL3 residues at the NBD2 transmission interface severely reduced P-gp assembly while changes to the equivalent residues in ICL1/ICL4 at the NBD1 interface had little effect. The hydrophobic nature at the transmission interfaces was also different. Mutation of Phe-1086 or Tyr-1087 to arginine at the NBD2 socket blocked activity or assembly while the equivalent mutations at the NBD1 socket had only modest effects. The results suggest that the NBD transmission interfaces are asymmetric. In contrast to the ICL2/3-NBD2 interface, the ICL1/4-NBD1 transmission interface is more hydrophilic and insensitive to mutations. Therefore the ICL2/3-NBD2 transmission interface forms a precise hydrophobic connection that acts as a linchpin for assembly and trafficking of P-gp.

  15. Super Ball Bot - Structures for Planetary Landing and Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Small, light-weight and low-cost missions will become increasingly important to NASA's exploration goals. Ideally teams of small, collapsible robots, weighing...

  16. Super Ball Bot - Structures for Planetary Landing and Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Small, light-weight and low-cost missions will become increasingly important to NASA's exploration goals for our solar system. Ideally teams of dozens or even...

  17. Solder joint technology materials, properties, and reliability

    CERN Document Server

    Tu, King-Ning

    2007-01-01

    Solder joints are ubiquitous in electronic consumer products. The European Union has a directive to ban the use of Pb-based solders in these products on July 1st, 2006. There is an urgent need for an increase in the research and development of Pb-free solders in electronic manufacturing. For example, spontaneous Sn whisker growth and electromigration induced failure in solder joints are serious issues. These reliability issues are quite complicated due to the combined effect of electrical, mechanical, chemical, and thermal forces on solder joints. To improve solder joint reliability, the science of solder joint behavior under various driving forces must be understood. In this book, the advanced materials reliability issues related to copper-tin reaction and electromigration in solder joints are emphasized and methods to prevent these reliability problems are discussed.

  18. O-Cell桩基承载力试验法在大直径超长钻孔嵌岩桩的应用%O-Cell Load Test for Rock-Socket Bored Piles with Large Diameter and Extra Length

    Institute of Scientific and Technical Information of China (English)

    刘亚东; 李胜; 史炳峰

    2012-01-01

    结合某桥梁大直径超长钻孔嵌岩桩承载力测试的实践,介绍了O-Cell桩基承载力试验原理和单桩极限承载力确定方法,对于荷载箱位置的选取及超长嵌岩桩成孔成桩工艺进行分析并提出自己的看法,为类似工程提供参考.%Based on the cumulative evidence of O-cell load test for rock-socket bored piles with large diameter and extra length for a bridge project, this paper introduces the theory of O-cell load test and the method of confirming the load. The positioning of loading equipment and the technology of boring and casting of long length rock-socket bored pile are also discussed and some views of the author are proposed to provide reference for similar projects.

  19. DYNAMICS AND FAULT DETECTION IN ROTOR BALL BEARING SYSTEM

    OpenAIRE

    Nilambari Shinde; D R . S. P. Shekhawat

    2015-01-01

    The dynamics of high speed rotating machinery plays an important role in the modern world. In the design of complex mechanical components and rotating machines, such as turbines, compressors , electrical machines, centrifuges or machine tool spindles, systematic analysis of dynamic behavior is needed. The dynamics of a rotor can be highly influenced by the design of support bearings, since, the critical speeds and the magnitude of v...

  20. Boiler and Pressure Balls Monopropellant Thermal Rocket Engine

    Science.gov (United States)

    Greene, William D. (Inventor)

    2009-01-01

    The proposed technology is a rocket engine cycle utilizing as the propulsive fluid a low molecular weight, cryogenic fluid, typically liquid hydrogen, pressure driven, heated, and expelled through a nozzle to generate high velocity and high specific impulse discharge gas. The proposed technology feeds the propellant through the engine cycle without the use of a separate pressurization fluid and without the use of turbomachinery. Advantages of the proposed technology are found in those elements of state-of-the-art systems that it avoids. It does not require a separate pressurization fluid or a thick-walled primary propellant tank as is typically required for a classical pressure-fed system. Further, it does not require the acceptance of intrinsic reliability risks associated with the use of turbomachinery

  1. Addendum to: Capillary floating and the billiard ball problem

    OpenAIRE

    Gutkin, Eugene

    2012-01-01

    We compare the results of our earlier paper on the floating in neutral equilibrium at arbitrary orientation in the sense of Finn-Young with the literature on its counterpart in the sense of Archimedes. We add a few remarks of personal and social-historical character.

  2. Separations: A Short History and a Cloudy Crystal Ball

    Science.gov (United States)

    Wankat, Phil

    2009-01-01

    Separations have played a major role in the history of chemical engineering and will continue to be important. Since separations have always been a major cost item in the process industries, they have always been a critical key to successful commercialization. First, while reviewing the history of separation processes we will observe that many…

  3. Charged Q-balls and boson stars and dynamics of charged test particles

    CERN Document Server

    Brihaye, Yves; Hartmann, Betti

    2014-01-01

    We construct electrically charged Q-balls and boson stars in a model with a scalar self-interaction potential resulting from gauge mediated supersymmetry breaking. We discuss the properties of these solutions in detail and emphasize the differences to the uncharged case. We observe that $Q$-balls can only be constructed up to a maximal value of the charge of the scalar field, while for boson stars the interplay between the attractive gravitational force and the repulsive electromagnetic force determines their behaviour. We also study the motion of charged, massive test particles in the space-time of boson stars. We find that in contrast to charged black holes the motion of charged test particles in charged boson star space-times is planar, but that the presence of the scalar field plays a crucial r\\^ole for the qualitative features of the trajectories. Applications of this test particle motion can be made in the study of extreme-mass ratio inspirals (EMRIs) as well as astrophysical plasmas relevant e.g. in th...

  4. Joint hypermobility: incidence and some clinical symptoms

    Directory of Open Access Journals (Sweden)

    M P Isaev

    2003-01-01

    Full Text Available Objective. To study joint mobility range among urban population aged 18 to 30 years and to assess association of joint and other connective tissue structures disorders clinical signs with hypermobility. Material and methods. 769 randomly selected individuals aged 18 to 30 (mean - 25,56 years (419 female and 350 male were examined. Hypermobility was assessed with 9-point Beighton scale. Examination included skin stretchability evaluation at elbow back surface, determination of flat feet, high palate, joint pain and deformities of knee joints, joint luxation and subluxation, hand and feet vasospastic disturbances, cardiac pain, oculist examination. Methods of variational statistics were used (x2, Student's test, Spirmen's correlation. Results. Hypermobility incidence and joint mobility in population aged 18 to 30 years in Orenburg largely comply with data received in Moscow. Joint mobility up to 5 points in women and up to 4 points in men is usual for persons of this age and in absence of additional clinical symptoms cannot be considered as pathological. Knee joint deformities, presence of high palate, cardiac pain accompanied by signs of vegetative dysfunction, hand and feet vasospastic disturbances are significantly connected with degree of joint mobility and in some cases can help in hypermobility syndrome diagnosis.

  5. Case Report: Late Complication of a Dry Socket Treatment

    Directory of Open Access Journals (Sweden)

    Ramón Manuel Alemán Navas

    2010-01-01

    Full Text Available Dry socket is often treated in dentistry with intra-alveolar dressings; the use of them remains controversial and has been related to some side effects such as neuritis, foreign body reactions, and myospherulosis. We present a case of an intra-alveolar dressing (zinc-oxide eugenol paste that mimicked a trigeminal neuralgia for 3 years and caused a right maxillary chronic osteomyelitis and foreign body reaction in a zone corresponding to the alveolus of the maxillary first molar. This long-term complication was successfully managed by complete removal of the foreign body and curettage of the affected area.

  6. Ceramic Rail-Race Ball Bearings

    Science.gov (United States)

    Balzer, Mark A.; Mungas, Greg S.; Peters, Gregory H.

    2010-01-01

    Non-lubricated ball bearings featuring rail races have been proposed for use in mechanisms that are required to function in the presence of mineral dust particles in very low-pressure, dry environments with extended life. Like a conventional ball bearing, the proposed bearing would include an inner and an outer ring separated by balls in rolling contact with the races. However, unlike a conventional ball bearing, the balls would not roll in semi-circular or gothic arch race grooves in the rings: instead, the races would be shaped to form two or more rails (see figure). During operation, the motion of the balls would push dust particles into the spaces between the rails where the particles could not generate rolling resistance for the balls

  7. Besov-Lipschitz and mean Besov-Lipschitz spaces of holomorphic functions on the unit ball

    CERN Document Server

    Jevtic, M

    2011-01-01

    We give several characterizations of holomorphic mean Besov-Lipschitz space on the unit ball in $\\cn $ and appropriate Besov-Lipschitz space and prove the equivalences between them. Equivalent norms on the mean Besov-Lipschitz space involve different types of $L^p$-moduli of continuity, while in characterizations of Besov-Lipschitz space we use not only the radial derivative but also the gradient and the tangential derivatives. The characterization in terms of the best approximation by polynomials is also given.

  8. Party of the Century: Truman Capote’s Black and White Ball

    OpenAIRE

    Rodman, Sarah Jane

    2014-01-01

    Party of the Century: Truman Capote’s Black and White Ball is a cultural history exhibition designed to transport museum visitors back to Capote’s masked dance held in New York City on November 28, 1966 in the Plaza Hotel’s Grand Ballroom. The interdisciplinary installation aims to reanimate host Truman Capote (1924-1984), author of Breakfast at Tiffany’s (1958) and In Cold Blood (1966); his honoree, Katharine Graham (1917-2001), President of the Washington Post; and the convergence of 540 at...

  9. Study of Thermophysical Properties of Silver Nanofluids by ISS-HD, Hot Ball and IPPE Techniques

    Science.gov (United States)

    Kouyaté, M.; Flores-Cuautle, J. J. A.; Slenders, E.; Sermeus, J.; Verstraeten, B.; Garay Ramirez, B. M. L.; San Martin Martinez, E.; Kubicar, L.; Vretenar, V.; Hudec, J.; Glorieux, C.

    2015-11-01

    In this work, the impulsive stimulated scattering technique, in a heterodyne diffraction detection configuration (ISS-HD), was used to study the dependence of the speed of sound and the thermal diffusivity on the concentration of silver nanoparticles in water, to which also d-glucose and carboxymethyl cellulose were added, in order to reduce sedimentation. The ISS-HD results, which show a slight increase of thermal diffusivity with increasing concentration, were cross-validated with results obtained by the inverse photopyroelectric method and the hot ball technique.

  10. Effects of metallic nanoparticle doped flux on the interfacial intermetallic compounds between lead-free solder ball and copper substrate

    Energy Technology Data Exchange (ETDEWEB)

    Sujan, G.K., E-mail: sgkumer@gmail.com; Haseeb, A.S.M.A., E-mail: haseeb@um.edu.my; Afifi, A.B.M., E-mail: amalina@um.edu.my

    2014-11-15

    Lead free solders currently in use are prone to develop thick interfacial intermetallic compound layers with rough morphology which are detrimental to the long term solder joint reliability. A novel method has been developed to control the morphology and growth of intermetallic compound layers between lead-free Sn–3.0Ag–0.5Cu solder ball and copper substrate by doping a water soluble flux with metallic nanoparticles. Four types of metallic nanoparticles (nickel, cobalt, molybdenum and titanium) were used to investigate their effects on the wetting behavior and interfacial microstructural evaluations after reflow. Nanoparticles were dispersed manually with a water soluble flux and the resulting nanoparticle doped flux was placed on copper substrate. Lead-free Sn–3.0Ag–0.5Cu solder balls of diameter 0.45 mm were placed on top of the flux and were reflowed at a peak temperature of 240 °C for 45 s. Angle of contact, wetting area and interfacial microstructure were studied by optical microscopy, field emission scanning electron microscopy and energy-dispersive X-ray spectroscopy. It was observed that the angle of contact increased and wetting area decreased with the addition of cobalt, molybdenum and titanium nanoparticles to flux. On the other hand, wettability improved with the addition of nickel nanoparticles. Cross-sectional micrographs revealed that both nickel and cobalt nanoparticle doping transformed the morphology of Cu{sub 6}Sn{sub 5} from a typical scallop type to a planer one and reduced the intermetallic compound thickness under optimum condition. These effects were suggested to be related to in-situ interfacial alloying at the interface during reflow. The minimum amount of nanoparticles required to produce the planer morphology was found to be 0.1 wt.% for both nickel and cobalt. Molybdenum and titanium nanoparticles neither appear to undergo alloying during reflow nor have any influence at the solder/substrate interfacial reaction. Thus, doping

  11. Case Report: Late Complication of a Dry Socket Treatment

    OpenAIRE

    Alemán Navas, Ramón Manuel; Martínez Mendoza, María Guadalupe

    2010-01-01

    Dry socket is often treated in dentistry with intra-alveolar dressings; the use of them remains controversial and has been related to some side effects such as neuritis, foreign body reactions, and myospherulosis. We present a case of an intra-alveolar dressing (zinc-oxide eugenol paste) that mimicked a trigeminal neuralgia for 3 years and caused a right maxillary chronic osteomyelitis and foreign body reaction in a zone corresponding to the alveolus of the maxillary first molar. This long-te...

  12. Case Report: Late Complication of a Dry Socket Treatment

    OpenAIRE

    Alemán Navas, Ramón Manuel; Martínez Mendoza, María Guadalupe

    2011-01-01

    Dry socket is often treated in dentistry with intra-alveolar dressings; the use of them remains controversial and has been related to some side effects such as neuritis, foreign body reactions, and myospherulosis. We present a case of an intra-alveolar dressing (zinc-oxide eugenol paste) that mimicked a trigeminal neuralgia for 3 years and caused a right maxillary chronic osteomyelitis and foreign body reaction in a zone corresponding to the alveolus of the maxillary first molar. This long-te...

  13. The motion of an arbitrarily rotating spherical projectile and its application to ball games

    International Nuclear Information System (INIS)

    In this paper the differential equations which govern the motion of a spherical projectile rotating about an arbitrary axis in the presence of an arbitrary ‘wind’ are developed. Three forces are assumed to act on the projectile: (i) gravity, (ii) a drag force proportional to the square of the projectile's velocity and in the opposite direction to this velocity and (iii) a lift or ‘Magnus’ force also assumed to be proportional to the square of the projectile's velocity and in a direction perpendicular to both this velocity and the angular velocity vector of the projectile. The problem has been coded in Matlab and some illustrative model trajectories are presented for ‘ball-games’, specifically golf and cricket, although the equations could equally well be applied to other ball-games such as tennis, soccer or baseball. Spin about an arbitrary axis allows for the treatment of situations where, for example, the spin has a component about the direction of travel. In the case of a cricket ball the subtle behaviour of so-called ‘drift’, particularly ‘late drift’, and also ‘dip’, which may be produced by a slow bowler's off or leg-spin, are investigated. It is found that the trajectories obtained are broadly in accord with those observed in practice. We envisage that this paper may be useful in two ways: (i) for its inherent scientific value as, to the best of our knowledge, the fundamental equations derived here have not appeared in the literature and (ii) in cultivating student interest in the numerical solution of differential equations, since so many of them actively participate in ball-games, and they will be able to compare their own practical experience with the overall trends indicated by the numerical results. As the paper presents equations which can be further extended, it may be of interest to research workers. However, since only the most basic principles of fundamental mechanics are employed, it should be well within the grasp of first

  14. Combined oculoplastic operation for contracted conjunctival sac and depressed eye socket of anophthalmos%Ⅱ期眼窝凹陷及结膜囊狭窄的联合整复手术

    Institute of Scientific and Technical Information of China (English)

    张向荣; 周琼; 裴重刚; 周荃; 高长华

    2011-01-01

    目的 探讨眼球摘除或眼内容物剜出术后眼窝内陷伴结膜囊狭窄的同期整复手术方法及临床疗效。方法 对2007年8月至2010年5月收治35例患者施行Ⅱ期义眼座植入联合结膜囊成形术,其中7例结膜囊轻度缺损采用下、上穹窿结膜划开;23例结膜囊中度缺损采用异体巩膜;5例结膜囊重度缺损采用自体唇粘膜移植。所有病例结膜囊内眼模支撑,轻、中度组行睑缘临时缝合,术后1月拆线,自体唇黏膜移植组行部分睑缘粘连术,术后3个月分开眼睑,试装义眼。观察术后眼窝内陷矫正、结膜囊成形情况。随访3~6月。结果 术后所有患者眼窝内陷明显改善,结膜囊成形良好,穹窿深浅可,均可配戴适合的义眼,活动度可。结论 Ⅱ期义眼座植入联合结膜囊成形术是治疗眼球摘除或眼内容物剜出术后眼窝内陷伴结膜囊狭窄的理想手术。%Objective To explore combined oculoplastic surgery methods for treating narrow conjunctival sac and sunk socket after enucleation or evisceration. Methods Thirty-five cases with narrow conjunctival sac and sunk socket were treated with secondary hydroxyapatite or Medpor orbital implantation combined with plasty of the cul - de - sac. Seven cases with mild impairment were cut open the bottom or top of the conjunctival fomix, 23 patients with moderate impairment were repaired by preserved sclera conjunctival sac, 5 eases of severe conjunctival defect were repaired by autologous oral mucosa transplants. An eye substitute was put in the conjunctival sac in every case. In mild and moderate impairment groups temporary palpebral suture were done, the eyelids were opened lmonth after surgery. The superior and lower eyelids were closed with partial blepharorrhaphy in oral mucosa transplant groups and the eyelids were opened 3 months after surgery and a suitable prosthesis was implanted. We observed the rectified sunk socket, the shaping

  15. Analysis and optimization of nitrile butadiene rubber sealing mechanism of ball valve

    Institute of Scientific and Technical Information of China (English)

    Xue-Guan SONG; Lin WANG; Young-Chul PARK

    2009-01-01

    An approach for analyzing and optimizing sealing mechanism of ball valve made of nitrile butadiene mbber(NBR) with finite element method was presented. The Mooney-Rivlin hyperelastic material model was chosen to characterize NBR sealing, as it has been recommended in the similar applications. That is, NBR sealing was modeled as incompressible hyperelasticity, as well as the assumption of isotropic flow. The results illustrate the structural pressure and contact pressure on the contact surface, which shows that the NBR sealing mechanism is very suitable for sealing after dimension optimization.

  16. The Equivalence of BMOA and VMOA on the Unit Ball of Cn

    Institute of Scientific and Technical Information of China (English)

    DongshengLiu

    1999-01-01

    In this paper, we characterize BMOA and VMOA on the unit ball in terms of normsNp(f)=sup/x∈B{1/σ(Q(z))∫Q(z)│f(ξ)-f(z)│pdσ(ξ)}1/p,1≤p<∞ and more general Garcia norms.Where Q(z)=Q(n(z),δz)={ξ∈S,│1/2<δZ}.n(z)={e1,z=0,/z/│z│,z=0,δz=[2(1-│z│)]1/2.

  17. The Power of a Soccer Ball: A Traumatic Open Finger Dislocation—A Rare Case Presentation

    Directory of Open Access Journals (Sweden)

    Turan Cihan Dülgeroğlu

    2015-01-01

    Full Text Available Proximal interphalangeal joint dislocations are injuries observed frequently and caused by axial loading on the finger in the extension. In this paper we present a traumatic open finger dislocation due to a ball hitting a wrestler. It was successfully treated with reduction and the volar plate and collateral bond fixation were applied with absorbable sutures.

  18. Evaluation of guided bone generation around implants placed into fresh extraction sockets: an experimental study in dogs

    DEFF Research Database (Denmark)

    Gotfredsen, K; Nimb, L; Buser, D;

    1993-01-01

    Immediate placement of implants into fresh extraction sockets would have the principal advantage of decreasing the recommended period of healing. It also would result in a guided placement of the implant, and it could reduce the resorption of the alveolar bone in the extraction area. However, when...... an implant is placed immediately into an extraction socket, it may not engage the walls of the socket near the crest of the alveolar ridge. With the presence of a bone defect around an implant, ingrowth of soft tissue could compromise the achievement of osseointegration in the crestal bone area....... The objective of this study was to evaluate the crestal bone healing response adjacent to implants placed immediately into fresh extraction sockets with and without covering membranes. Eight adult mongrel dogs had the third and fourth mandibular premolars extracted bilaterally. Thirty-two submerged titanium...

  19. VECTOR-VALUED HOLOMORPHIC FUNCTIONS ON THE COMPLEX BALL AND THE ANALYTIC RADON-NIKODYM PROPERTY

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The complex Banach spaces X with values in which every bounded holomorphic function in the unit ball B of Cd(d > 1) has boundary limits almost surely are exactly the spaces with the analytic Radon-Nikodym property.The proof is based on inner Hardy martingales introduced here.The inner Hardy martingales are constructed in terms of inner functions in B and are reasonable discrete approximations for the image processes of the holomorphic Brownian motion under X-valued holomorphic functions in B.

  20. Prosthetic rehabilitation of an ocular defect with post-enucleation socket syndrome: A case report.

    Science.gov (United States)

    Amornvit, Pokpong; Rokaya, Dinesh; Shrestha, Binit; Srithavaj, Theerathavaj

    2014-01-01

    Ocular trauma can be caused by road traffic accidents, falls, assaults, or work-related accidents. Enucleation is often indicated after ocular injury or for the treatment of intraocular tumors, severe ocular infections, and painful blind eyes. Rehabilitation of an enucleated socket without an intraocular implant or with an inappropriately sized implant can result in superior sulcus deepening, enophthalmos, ptosis, ectropion, and lower lid laxity, which are collectively known as post-enucleation socket syndrome. This clinical report describes the rehabilitation of post-enucleation socket syndrome with a modified ocular prosthesis. Modifications to the ocular prosthesis were performed to correct the ptosis, superior sulcus deepening, and enophthalmos. The rehabilitation procedure produced satisfactory results.