Horizontal lift of affinor structures and its applications

Abstract In this paper we present a bundle of pairs of volume forms V2. We describe horizontal lift of a tensor of type (1; 1) and we show that horizontal lift of an almost complex structure on a manifold M is an almost complex structure on the bundle V2. Next we give conditions under which the almost complex structure on V 2 is integrable. In the second part we find horizontal lift of vector fields, tensorfields of type (0; 2) and (2; 0), Riemannian metrics and we determine a family of a t-connections on the bundle of pairs of volume forms. At the end, we consider some properties of the horizontally lifted vector fields and certain infinitesimal transformations.

Download Full-text

Water Confinement Effects in Response of Fuel Assembly to Faulted Condition Loads

12th International Conference on Nuclear Engineering, Volume 2 ◽

10.1115/icone12-49566 ◽

2004 ◽

Author(s):

S. J. Shah ◽

B. Brenneman ◽

G. T. Williams ◽

J. H. Strumpell

Keyword(s):

Fuel Assembly ◽

Reference Frame ◽

Reactor Core ◽

Axial Flow ◽

Pressure Gradients ◽

Baffle Plate ◽

Horizontal Lift ◽

Velocity Modeling ◽

Fuel Assemblies ◽

Large Flow

It has been established by other authors [1] that the accelerations of the water confined by the reactor core baffle plates has a significant effect on the responses of all the fuel assemblies during LOCA or seismic transients. This particular effect is a consequence of the water being essentially incompressible, and thus experiencing the same horizontal accelerations as the imposed baffle plate motions. These horizontal accelerations of the fluid induce lateral pressure gradients that cause horizontal buoyancy forces on any submerged structures. These forces are in the same direction as the baffle accelerations and, for certain frequencies at least, tend to reduce the relative displacements between the fuel and baffle plates. But there is another confinement effect — the imposed baffle plate velocities must also be transmitted to the water. If the fuel assembly grid strips are treated as simple hydro-foils, these horizontal velocity components change the fluid angle of attack on each strip, and thus may induce large horizontal lift forces on each grid in the same direction as the baffle plate velocity. There is a similar horizontal lift due to inclined flow over the rods when axial flow is present. These combined forces appear to always reduce the relative displacements between the fuel and baffle plates for any significant axial flow velocity. Modeling this effect is very simple. It was shown in previous papers [2,3] that the mechanism for the large fuel assembly damping due to axial flow may be the hydrodynamic forces on the grid strips, and that this is very well represented by discrete viscous dampers at each grid elevation. To include the imposed horizontal water velocity effects, on both the grids and rods, these dampers are simply attached to the baffle plate rather than “ground”. The large flow-induced damping really acts in a relative reference frame rather than an absolute or inertial reference frame, and thus it becomes a flow-induced coupling between the fuel and baffles. This has a significant effect on the fuel assembly motions and tends to reduce the relative displacements and impact forces between fuel assemblies and baffle walls.

Download Full-text

Horizontal lift of symmetric connections to the bundle of volume forms ν

Annales Universitatis Mariae Curie-Sklodowska sectio A – Mathematica ◽

10.2478/v10062-010-0004-z ◽

2010 ◽

Vol 64 (1) ◽

Author(s):

Anna Gąsior

Keyword(s):

Horizontal Lift ◽

Volume Forms

Download Full-text

Task-Contingent Persistence is Related to Better Performance-Based Measures in Patients with Chronic Musculoskeletal Pain

Pain Research and Management ◽

10.1155/2020/1765456 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Cyrille Burrus ◽

Philippe Vuistiner ◽

Bertrand Léger ◽

Gilles Rivier ◽

Roger Hilfiker ◽

...

Keyword(s):

Activity Patterns ◽

Lift Coefficient ◽

Negative Influence ◽

Functional Capacity Evaluation ◽

Dominant Hand ◽

Behavioral Strategies ◽

Horizontal Lift ◽

Linear Regression Models ◽

Trauma Severity ◽

Capacity Evaluation

Purpose. Pacing, avoidance, and overdoing are considered the three main behavioral strategies, also labeled activity patterns. Their relationship with functioning of patients with chronic pain is debated. The purpose of this study was to measure the influence of activity patterns on lifting tasks commonly used in daily life. Method. We performed a monocentric observational study and included patients performing Functional Capacity Evaluation (FCE). Avoidance, pacing, and persistence were assessed with using the Patterns of Activity Measures–Pain (POAM-P). Maximal safe performance was measured for floor-to-waist, waist-to-overhead, horizontal lift, and carrying with dominant-hand tests according to the FCE guidelines. Descriptive statistics, associations of POAM-P subscales with various sociodemographic variables, and correlations are presented. Standard multiple linear regression models were applied to measure the associations between FCE tests and POAM-P subscales, adjusting for the following potential confounders: age, gender, body mass index (BMI), pain severity, trauma severity, localization of injury, and education. Results. Persistence was significantly positively associated with performance on the 4 FCE tests: floor-to-waist (coefficient = 0.20; p=0.001), waist-to-overhead (coefficient = 0.13; p=0.004), horizontal lift (coefficient = 0.31; p≤0.001), and dominant-handed lifting (coefficient = 0.19; p=0.001). Pacing was found to have a negative influence on the carrying dominant-hand test (coefficient = –0.14; p=0.034), and avoidance was not found to have an influence on the 4 FCE tests. Conclusion. This study shows that task-persistence pattern is positively associated with physical performance in FCE, whereas pacing can have a negative influence on some tests.

Download Full-text

The Design of PLC Control of Multi Degree of Freedom Landscape Showcase

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1030-1032.1554 ◽

2014 ◽

Vol 1030-1032 ◽

pp. 1554-1557

Author(s):

An Liu ◽

Jing Tao Wei

Keyword(s):

Electric Motor ◽

Degree Of Freedom ◽

Horizontal Lift ◽

Visual Effects ◽

Plc Control ◽

Mechanical Components ◽

Operation Results

In order to make the different angles of the viewers get the best visual effects, the paper proposed a lift tilt rotary landscape showcase which can show all kinds with multi-degree of freedom. Showcase uses the electric motor to drive and PLC applications in the system which can be programmed to control various types of mechanical components, to achieve the function of lifting and descending of 4 position, 8 position, and 12 position, horizontal lift and rotating in 360-degree. The test and operation results demonstrate that the showcase meets the specific functional demand of design.

Download Full-text