The Development of the Simple Transfer Instrument for Reducing the Burden of Caregivers: Effect of Back Support Length

2017 ◽  
Author(s):  
Shuang Li ◽  
Tianmin Guan ◽  
Dezhu Zhao
Keyword(s):  
Support Length

scholarly journals Study on the additional support length requirements of single-span bridges due to skew using a simplified method

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Suiwen Wu ◽  
Junfeng Jia ◽  
Chiyu Jiao ◽  
Junfei Huang ◽  
Jianzhong Li
Keyword(s):  
Aspect Ratio ◽  
Response Spectrum ◽  
Skew Angle ◽  
Empirical Formulas ◽  
Design Response Spectrum ◽  
Skew Bridges ◽  
Simplified Method ◽  
Additional Support ◽  
Linear Manner ◽  
Support Length

AbstractSkew bridges with seat-type abutments are frequently unseated in earthquakes due to large transverse displacements at their acute corners. It is believed these large displacements are due to in-plane rotation of the superstructure. Lack of detailed guidelines for modeling of skew bridges, many current design codes give empirical expressions rather than theoretical solutions for the additional support length required in skew bridges to prevent unseating. In this paper, a parametric study has been carried out to study the influence of skew angle, aspect ratio and fundamental periods of bridges on the additional support length requirements of single-span bridges due to skew using a shake table experiment validated Simplified Method, which is capable of simulating gap closure based on response spectrum analysis. This method is developed based on the premise that the obtuse corner of the superstructure engages the adjacent back wall during lateral loading and rotates about this corner until the loading reverses direction. A design response spectrum specified in AASHTO LRFD Specifications was employed to represent the design-level earthquakes. The results show the additional length required to prevent unseating due to skew increases with the skew angle in an approximately linear manner when the angle is less than a critical value and decreases for angles above this value. This critical skew angle increases with the aspect ratio approximately in a linear manner and shows negligible dependence on the fundamental periods of the bridges, and combination of span length and width. In addition, the critical skew angle varies between 58° and 66°, when the aspect ratio is varied from 3.0 to 5.0. The results also show that the empirical formulas for minimum support length requirements of skew bridges in current codes and specifications can not accurately reflect the influence of skew.

Investigations on Edge Chipping in Rotary Ultrasonic Machining Using Finite Element Analysis

2006 ◽  
Vol 532-533 ◽  
pp. 969-972 ◽  
Author(s):  
Yu Chen ◽  
Zhi Jian Pei ◽  
Clyde Treadwell
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Cutting Force ◽  
Ultrasonic Machining ◽  
Rotary Ultrasonic Machining ◽  
Cutting Depth ◽  
Element Analysis ◽  
Edge Chipping ◽  
Support Length

This paper reports two investigations on the edge chipping in rotary ultrasonic machining using finite element analysis (FEA). The first FEA investigation establishes a relationship between edge chipping thickness and cutting force. The second FEA investigation is to understand the effects of three parameters (cutting depth, support length, and pre-tightening load) on edge chipping thickness. The investigation results showed that the edge chipping thickness could be reduced by increasing support length and decreasing cutting force.

scholarly journals A Method to Calculate the Support Length of Beams Resting on Masonry Walls

Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7131
Author(s):  
Marco Andrea Pisani ◽  
Massimiliano Bocciarelli ◽  
Tommaso D’Antino
Keyword(s):  
Contact Pressure ◽  
Professional Practice ◽  
Analytical Procedure ◽  
Steel Beams ◽  
Construction Engineering ◽  
Load Carrying ◽  
Different Types ◽  
Important Challenge ◽  
Support Conditions ◽  
Support Length

Rehabilitation, strengthening, and retrofitting of existing masonry buildings represent an important challenge for the construction engineering field. Often, slab strengthening/retrofitting is performed by replacing existing timber and steel beams or by adding new beams to improve the slab load-carrying capacity. The computation of the stresses at the beam–masonry interface (i.e., the contact pressure) is crucial to properly design the beam support length, preventing local failure of masonry and beam. This paper presents a simple analytical procedure to compute the contact pressure at the beam–masonry interface. The analytical procedure is validated by comparison between analytical and corresponding numerical results obtained by finite element modeling. Different types of beam (solid and laminated timber beams and steel beams) were considered, as well as different support conditions (simply resting on the wall considering different support lengths or fully embedded). The results obtained show that the method proposed is simple and reliable, which makes it suitable for professional practice.

Kinematic Analysis of Elbow and Scapula Based on Changes in Arm Support Length and Central Axis Location Through Rotational Motion of Upper Limb

2012 ◽  
Author(s):  
Jae Soo Hong ◽  
Keyoung Jin Chun ◽  
Jong Hyun Kim ◽  
Jung Hwa Hong
Keyword(s):  
Upper Limb ◽  
Central Axis ◽  
Upper Body ◽  
Angular Width ◽  
Long Distance ◽  
Rotational Movement ◽  
Design Variables ◽  
Flexion Extension ◽  
Arm Support ◽  
Support Length

An increase in the aging population around the world and in degenerative diseases has caused an epidemic of stroke. Hence, rehab equipment for treating its after-effects has been actively developed. A repeated upper-body rehab exercise is required and this exercise can only yield good results when its accurate motion is guided by a therapist. However, few kinematics studies have been conducted based on design variables such as changes in the rotational central axis and body measurement. So, this study analyzed the angular changes in two motions of the elbow (Flexion-Extension: F-E, Pronation-Supination: P-S) and three motions of the scapula (Anterior-Posterior tilt: A-P, Internal-External rotation: I-E, Upward-Downward rotation: U-D) based on changes in the arm support length and central axis location. Eight healthy subjects participated in this study. Rehabilitation equipment for the upper limb, which can be adjusted to different arm support lengths and central axis locations, was used as the experimental equipment. The length could be adjusted to five levels (280 mm, 220 mm, 160 mm, 100 mm, and 40 mm). In the case of an experiment involving changes in the axis locations, the length was fixed as 280 mm, which allowed five different axis locations. Each subject implemented a rotational movement passively at an angular velocity of 30°/s. In this study, we observed changes in the motion patterns of the upper-limb rotational movement based on the length and the location. The patterns based on the two design variables revealed a consistent tendency under the elbow (forearm) and the scapula (shoulder rhythm). Yet, three scapula motions showed little changes in the angular width, and only I-E showed an angular width of 5°. First, with respect to the tendency of the five motions based on changes in the lengths, the prolonged length showed a decreased angular width. Second, in terms of the tendency of the five motions based on changes in the locations, a relatively long distance between the handle and the axis (Location 1 → Location 5) confirmed a decreased angular width owing to a relatively small rotational movement at Location 5. The F-E motion of the elbow clearly showed two time cycles per rotation. Other motions revealed one time cycle per rotation. With respect to the upper-body rotational movement, we confirmed that motions related to the forearm were more active than motions related to the shoulder.

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