• Structural Engineering and Mechanics
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• v.41 no.6
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• pp.735-750
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• 2012

This paper presents a comparison between two different procedures to deal with the geometric nonlinear analysis of space trusses, considering its structural stability aspects. The first nonlinear formulation, called positional, uses nodal positions rather than nodal displacements to describe the finite elements kinematics. The strains are computed directly from the proposed position concept, using a Cartesian coordinate system fixed in space. The second formulation, called corotational, is based on the explicit separation between rigid body motion and deformed motion. The numerical examples demonstrate the performances and the convergence of the responses for both analyzed formulations. Two numerical examples were compared, including a lattice beam with postcritical behavior. Despite the two completely different approaches to deal with the geometrical nonlinear problem, the results present good agreement.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.1
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• pp.144-153
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• 1997

The determination of the direct kinematics of the parallel mechanism is a difficult problem but has to be solved for any practical use. This paper presents the efficient formulation of the direct kinematics for double parallel robot arm. The robot arm consists of two parallel mechanism, which generate positional and orientational motions, respectively. These motions are decoupled by a passive central axis which is composed of four revolute joints and one prismatic joint. For a set of given lengths of linear actuators, the direct kinematics will find the joint displacements of th central axis from geometric constraints in each parallel mechanism. Then the joint displacements will be converted into the position and the orientation of the end effector of the robot arm. The proposed formulation is decoupled and compacted so that it will be implemented as a real-time direct kinematics. With the proposed formulation, we analyze the motion of the double parallel robot and show its characteristics. Specially, we investigate the workspace in terms of positional space as well as orientational space.

• Journal of Society of Preventive Korean Medicine
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• v.28 no.1
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• pp.89-107
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• 2024

Objectives : To investigate the clinical usage of Banhabaekchulcheonmatang (BBCT), this study reviewed clinical studies conducted in Korea. Method : Literature search was performed on four Korean database; OASIS, RISS, KTKP and NDSL. Studies published before July 2023 were categorized and analyzed according to the target disease. Results : Fifty-four studies including 36 single case reports and 18 case series were included in this review and the total number of case patients was 79. There were 24 patients with peripheral vertigo such as benign paraoxysmal positional vertigo and Meniere's disease, 17 with central vertigo such as cerebellar infarction, 15 with vertigo accompanied by digestive symptoms, 13 with headache, and 10 with other diseases. Vertigo treatment accounted for more than 70% of the total case and there was no cases of hypertension and dementia. The BBCT formulation used was decoction in 69 patients (87.3%), powder in 7 patients (8.9%), and combination of decoction and powder in 3 patients (3.8%). Conclusion : Clinical research should be accumulated to expand the use of BBCT in the treatment of hypertension and dementia. In order to increase the use of insurance-covered extract preparation, it is necessary to make an effort to include the various diseases actually treated with BBCT in the indications.