• Proceedings of the Korean Geotechical Society Conference
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• 1987.06a
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• pp.51-80
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• 1987

In this studys a numerical analysis on the defomation of foundation layer was carried out by indroducing joint element. The method using the joust element between adj assent different materials has been originally developed for rock behavior(Goodman, et al. 1968) . The application of this method to the interface between the footing and soil layer proved satisfactory(Ghaboussi p et at. 1973). Authors tried to obtain the deformation of rrcompound foundation layerg", which vertically or horizontally or both consists of the natural(or intact) soft clay layer and the layer improved artificially in order to get high stiff-fness with replacement or chemical treatment to reduce the excessively detrimental settlemellt or lateral displacement in case of banking or building the civil structure on the soft layer. The joint conditions were classified into three categories : contacts sliding and separation. By coupling "JOINT" as a subroutine into multi-purpose code for the finite element method of the foundatlion daveloped by authors on the assumption that shearing and normal displacement can not be coupledl which terms pinon-dilatant" and by selecting modified Cam-clay modeIP the deformation analysis was performmed. The results using joint element were compared with those secured without introduction of joint element Nain results analized are as follows : 1. For the prediction of settlement and lateral desplacement, the result due to joint element was evaluated larger, which was regarded safe. 2. For the determination of ultimate bearing capacetyi the value using joint element appeared smaller by 20%, which was also safe.

• The Journal of Korea Robotics Society
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• v.11 no.1
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• pp.26-32
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• 2016

A variable release torque-based compliance spring-clutch (VCSC) is presented. VCSC is a safe joint to reduce the impact of collisions between humans and robots. It is composed of four functional plates, balls, springs to make some functions in compliant movement, release mechanism, gravity compensation during its work. Also, it can estimate torque applied to a joint by using distance sensor and parameters of cam profile. The measured variable torque of prototype is 4.3~7.6 Nm and release torque is 4.3 Nm. In our future studies, a calibration for torque estimation will be conducted.

• Journal of the Korea Convergence Society
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• v.6 no.3
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• pp.13-18
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• 2015

This paper is the study on the safe design of joint controling the pressure and temperature by connecting between pipes laying with the flexible joint. This study aims at decreasing the excessive pressure applied in the pipe and preventing the accident occurrence in order to solve the pipe damage by extraction and contraction due to the pressure of open air and transport gas. The flow properties of each model are investigated through the simulation analysis by applying three kinds of the flexible joints. When transport gas passes the flexible joint, the flow characteristics of heat, pressure and velocity at pipe laying are analyzed. It is thought to be contributed to the safe design due to the shape of the flexible joint by using the result of this study. And it is possible to be grafted onto the convergence technique at design and show the esthetic sense.

• Journal of muscle and joint health
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• v.28 no.3
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• pp.283-292
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• 2021

Purpose: In this descriptive study, we aimed to identify factors influencing safe nursing activities of nurses working at public hospitals. Methods: We collected data in March 2021 through an online survey. The subjects were 199 nurses who had worked for at least six months at public hospitals. The self-reported questionnaire consisted of items pertaining to safe nursing activities, perception of patient safety culture, and the general characteristics of the subjects. To examine the differences in the safe nursing activities and perception of patient safety culture by general characteristics, we employed a t-test and ANOVA. We conducted a multiple linear regression analysis to explore the factors affecting safe nursing activities. Results: The mean score for safe nursing activity was 4.59±0.39. Perception of patient safety culture and age group were found to be the main factors affecting the safe nursing activities of nurses working at public hospitals (F=17.24, p<.001, Adj. R²=.40). When the score for perception of patient safety culture increased by 1 point, the score for safe nursing activities increased by 0.58 points. In addition, the score for safe nursing activity in the 40s age group was 0.16 points higher than for those in the 20s age group. Conclusion: Effective management and leadership in public hospitals is needed to improve the culture of patient safety at various levels so as to ensure safe nursing activities.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2010-2015
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• 2003

In this paper, a design and control of the safe arm with passive compliant joints(PCJ) is presented. Each PCJ has a magneto- rheological damper and maximum 6 springs. Compliance analysis in Cartesian space is performed with the compliance ellipsoid; this analysis shows a map between compliance in the joint space and compliance in Cartesian space. Vibration control of the arm using an input shaping technique is also presented; the results of a simulation and an experiment prove that a fast motion of the safe arm without residual vibration can be performed.

• The Academic Congress of Korean Shoulder and Elbow Society
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• 2004.11a
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• pp.176-179
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• 2004

Arthroscopy of the stiff elbow joint is a technically difficult procedure because of the decreased joint space of the elbow joint. even to experienced surgeons. Problems encountered include limited access of instrument to the intra-articular ,pace and an increased risk of cartilage injury in the contracted elbow joint. This study describes a novel transarticular approach for elbow arthroscopy that allow, the safe and effective creation of the proximal medial and lateral portals.

• The Journal of Korea Robotics Society
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• v.9 no.4
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• pp.264-271
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• 2014

In this study, we have developed the humanoid joint modules which provide a variety of service while living with people in the future home life. The most important requirement is ensuring the safety for humans of the robot system for collaboration with people and providing physical service in dynamic changing environment. Therefore we should construct the mechanism and control system that each joint of the robot should response sensitively and rapidly to fulfill that. In this study, we have analyzed the characteristic of the joint which based on the target constituting the humanoid motion, developed the optimal actuator system which can be controlled based on each joint characteristic, and developed the control system which can control an multi-joint system at a high speed. In particular, in the design of the joint, we have defined back-drivability at the safety perspective and developed an actuator unit to maximize. Therefore we establish a foundation element technology for future commercialization of intelligent service robots.

• Tunnel and Underground Space
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• v.8 no.4
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• pp.351-358
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• 1998

A statistical method for assessing the joint persistence based on the in-situ measurement of joint trace length has been derived. This method utilizes the probability density distribution of either the joint trace length or the diameter of hypothetically circular joint diameter depending on the relative size of joint surface to that of the potential keyblock. The stability of potential keyblock with different sizes and joint persistences has been also calculated to illustrate the applicability of the developed method to the design and the safe excavation of large scale underground openings.

• Earthquakes and Structures
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• v.7 no.5
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• pp.705-718
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• 2014

This paper presents an analytical model for determining the transverse reinforcement required for reinforced concrete exterior beam-column joints subjected to reversed cyclic loading. Although the joint aspect ratio can affect joint shear strength, current design codes do not consider its effects in calculating joint shear strength and the necessary amount of transverse reinforcement. This study re-evaluated previous exterior beam-column joint tests collected from 11 references and showed that the joint shear strength decreases as the joint aspect ratio increases. An analytical model was developed, to quantify the transverse reinforcement required to secure safe load flows in exterior beam-column joints. Comparisons with a database of exterior beam-column joint tests from published literature validated the model. The required sectional ratios of horizontal transverse reinforcement calculated by the proposed model were compared with those specified in ACI 352R-02. More transverse reinforcement is required as the joint aspect ratio increases, or as the ratio of vertical reinforcement decreases; however, ACI 352R-02 specifies a constant transverse reinforcement, regardless of the joint aspect ratio. This reevaluation of test data and the results of the analytical model demonstrate a need for new criteria that take the effects of joint aspect ratio into account in exterior joint design.

• Journal of the Korean Society for Railway
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• v.5 no.3
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• pp.133-141
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• 2002

Recently developed JES(Joint Element Structure) Method was researched as a more safe and economic method than other under pass construction method and was applied to many construction sites. The joint element connection of JES Method is the most important factor for the to behavior of structure. The connection of JES method is filled with the mortar, and the steel and mortar of connections produce the same behavior as one material. The results of experience and numerical analysis are following: The maximum internal stress of connection is decided by the end of connection. also, The connection of joint element structure method have sufficient internal stress against fatigue.