• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.2
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• pp.154-158
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• 2013

Expansion joint has been utilized in many areas including automotive bellows for exhaust system. Usage of expansion joint has been increased due to its inherent flexibility and excellent anti-vibration property. Simple shape of expansion joint is modeled to understand the behavior of joint system. 27 design cases using 3 design factors with 3 levels are constructed by design of experiment. Each case is simulated to find the most influential design factors. Response for this study, maximum stress in the expansion joint, has been used to determine main design factors of joint. Among the 3 design factors, factor B has affected greatly a response in the formation of optimum shape of joint. Also, interaction factor, $A{\times}B$, has also showed its influence to the response of joint. This study showed that design of experiment combined with finite element analysis could be used in the design decision process effectively in the design of expansion joint.

• Korean System Dynamics Review
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• v.13 no.1
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• pp.113-131
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• 2012

Applying social network analysis techniques, this study examines complex system characteristics of industry-university joint research R&D networks. In specific, it focuses on whether these R&D networks comply with the power law, whose system typically presents the-rich-get-richer and the-poor-get-poor patterns. The basic data come from 7,751 industry-university joint research projects, all of which were carried out by Daejeon, Chungbuk, and Chungnam-based universities from January 2005 to October 2008. The empirical results reveal that the R&D networks abide by the power law. That is, a handful of business units and universities command an overwhelming majority in the joint links, indicating positive feedback dominance within the system.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.764-767
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• 1997

This paper presents the modulation of the dexterity of a parallel manipulator using joint freezing/releasing and joint unactuation/actuation. In this paper, individual limbs have redundant number of joints, and each joint can be frozen/released and unactuated/actuated, as needed. First, given a task, the restrictions on joint freezing and joint unactuation of a parallel manipulator are derived. Next, with/without joint freezing and/or joint unactuation, the kinematics of a parallel manipulator is formulated, based on which the manipulability ellipsoid is defined. The effects of joint freezing and joint unactuation on the manipulability are analyzed and compared. Finally, simulation results for a planar parallel manipulator are given. Joint mechanisms, such as joint freezing and joint unactuation, are rather simple to adopt into a parallel manipulator, but is quite effective to improve the task adaptability of the system.

• Korean Journal of Occupational Health Nursing
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• v.7 no.1
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• pp.97-114
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• 1998

The occupational health services for the minor enterprises are poor comparing with that of large enterprises in Korea. In 1997, Korean government announced officially the law on joint employment system of occupational health practitioners to solve the problems. This study is to develop the model on the joint employment system of occupational nurse practitioners for minor enterprises in Korea based on the opinions of occupational health nurses (OH Ns). The data were collected by questionnares from October to November in 1997. The number of subjects was 210 occupational health nurses who had participated the mandatory nursing education program provided by the Korean Occupational Health Nurses Association(KOHNA). The response rate was 47.1%. The contents of questionnaires were general characteristics, occupational & job characteristics of OHNs, and the views on the joint employment system. The SAS-PC program was used for the statistical analysis. The results were as followed, (1) The proper number of industies was 3 and the appropriate number of workers was 448 for one joint employed occupational nurse practitioner (J EONP). (2) 44.7% of the OHNs wanted that the Ministry of Labor monitored the way and content of contraction b/w JEONP and minor emterprises, 82.6% of the OHNs wanted that KOHNA managed the employment informations. (3) The OHNs of occupational health agencies showed more positive attitude than the OHNs of private industries on the joint employment system. (4) 88.3% of the OHNs wanted the education training for JEONP. Especially in occupational hygiene and safety control. (5) The OHNs expected the role expansion of Occupational Health Nursing by JEONP system. At the same time they worried the adverse effects. For the successful execution of this system, it is necessary the cooperation among the Ministry of Labor, KOHNA, the minor enterprises, and the OHNs.

• Tunnel and Underground Space
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• v.24 no.1
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• pp.55-66
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• 2014

In this study, a joint survey system was developed to efficiently analyze geometrical characteristics of joint structures in rock mass using photogrammetric technique. The system includes both hardware and software. The hardware consists of a high resolution image camera for photographing image of a surface of rock body, a direction controlling system for adjusting the attitude of camera, and a digital compass for measuring the rotation angle of camera. The software was also developed in order to analyze the orientation, density, mean length of joints revealed on the images of rock surfaces. The software developed in this study was named as JointeXtractor. As applying this system into several field measurements, the orientation, density, mean length of joints could be quantitatively measured through analyzing the images of rock surfaces, in which the case of a difficult-to-access area was especially included for the test of the system.

• Journal of Information Technology and Architecture
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• v.11 no.2
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• pp.187-199
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• 2014

The DoD of United State, the MoD of United Kingdom and NATO have developed and implemented not only the concepts of joint capability but also management system for the joint capability to respond the future uncertain operations effectively. The resources of the DoD in United State have been efficiently planning, programming, budgeting, execution and evaluation using the PPBEE system which developed based on the concept of joint capability. The joint capability of the DoD has been managing through the JCAMS (Joint Capability Area Management System) which constructed based on JCA, UJTL and so on. Recently the MND of Korea eager to try introducing concept of the JCMS and developing the JCMS like the JCAMS of DoD for the future joint operation in the uncertain environment. We propose the holistic mechanism to develop the JCMS (Joint Capability Management System) of MND which can implement during the constructing the JCMS of Korea efficiently and effectively.

• Korean Journal of Applied Biomechanics
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• v.16 no.4
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• pp.105-113
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• 2006

The purpose of this study was to analyze the joint torque of triple segmental system in golf driver swing. For this purpose, joint torque were calculated. In order to determine the load on the lumbar region, a triple segmental system was set for wrist, left shoulder and lumbar, torque working on the lumbar region were estimated. For this study, a total of 7 professional golfers were sampled, and then, their driver swings were recorded with two high-speed digital video cameras (180 frames/sec.) to be synthesized into 3-dimensional images and coordinated. Then, Eular's equation was used to produce some kinematic data, which were used to calculate joint torque with Newton's function. All data were calculated using LabVIEW 6.1 graphic program. The results of this study can be summarized as follows; It was found that the joint torque was generated in the direction opposite the target on wrist and shoulder during down swing, while in the direction towards the target on the lumbar region. During impact and release, the torque on the wrist joint was converted from the direction opposite the target to the direction towards the target, while the torque on the lumbar region was generated vice versa. The joints on the club-arm-shoulder were generated in the opposite direction at the beginning of down swing when the torque on the thorax-pelvis began to be generated, and then, the torque on the thorax-pelvis began to lower, while that on the club-arm-shoulder began to increase. Thus, a rapid decrease of the torque on the lumbar region linked to the low trunk acted to increase moment and joint torque on the arm-club region.

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.1
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• pp.197-204
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• 2005

Multipurpose Floor Level Joint(MFLJ) is a new construction technology system which was developed in domestic. By using this system, it is possible not only to absorb the deformation at expansion joint due to shrinkages of concrete but also to make ease the floor leveling during the concrete casting at floor. The system consists of two elements, supporting devices and rails. Their structural capacities were verified through several experimental programs, such as compressive strength test of support and bending test of rail. The purpose of this paper is to evaluate the deformation absorbing capacity of the floor level joint. An experimental work was carried out to simulate the deformation condition at the joint and the test result was analyzed and evaluated. In addition, FEM analysis for expansion joint of typical building was also performed to predict the real behavior of MFLJ. The test results showed that MFLJ has sufficient deformation capacity required to act as expansion joint.

• KIPS Transactions on Computer and Communication Systems
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• v.11 no.2
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• pp.59-66
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• 2022

The Joint Coastal Guard System is composed of a maritime surveillance system and a anti-coastal infiltration system, and is a system in which the Navy is mainly responsible for the maritime and the Army is responsible for the coast. We analyzed the operations effectiveness of the joint coastal guard system, in which various weapon systems of the army and navy are operated in a complex way, to the extent to which successful operation is possible against small targets. The operations effectiveness analysis was conducted by defining the operations effectiveness by operation type, configuring the simulation environment using METT-T elements, establishing the assumptions of the simulation scenario, conducting the simulation and analyzing the simulation results by weather condition. The simulation tools used were NORAM and EADSIM. As a result of the operations effectiveness analysis, the joint coastal guard system currently in operation showed a significant difference in operational success depending on the size of the target and weather conditions. This research can be used as useful data for establishing an effective joint coastal guard system and conducting systematic guard operations.

• Transactions on Control, Automation and Systems Engineering
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• v.2 no.1
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• pp.56-61
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• 2000

Majority of industrial robots are controlled by a simple independent joint control of joint actuators rather than complex controllers based on the nonlinear dynamic model of the robot manipulator. In this independent joint control scheme, the performance of actuator control is influenced significantly by the joint disturbance torques including gravity, Coriolis and centrifugal torques, which result in the trajectory tracking error in the joint control system. The control performance of a redundant manipulator under independent joint control can be improved by minimizing this joint disturbance torque in resolving the kinematic redundancy. A 3 DOF planar robot is studied as an example, and the dynamic programming method is used to find the globally optimal joint trajectory that minimize the joint disturbance torque over the entire motion. The resulting solution is compared with the solution obtained by the conventional joint torque minimization, and it is shown that joint disturbance can be reduced using the kinematic redundancy.