• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.73-73
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• 2000

Assembly is usually performed by one robot and fixtures. This type of assembly system has Low flexibility in terms of variety of parts and part-presentation that the system can handle. This paper addresses assembly without fixtures using two-manipulator robot. An active method using force feedback is proposed for the peg-in-hole assembly in highly uncertain environment. Assembly states are described by extended contact relations. Qualitative templates for events are easily derived from the token vector of the Petrinet model. The states are recognized through identification of the events using two 6-d.o.f force/moment sensors. The proposed method is verified and evaluated through experiments with round peg- in-hole assembly.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.9
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• pp.49-55
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• 2010

Many electric poles in the softground have been collapsed due to external load. In this study, 10 types of tests were performed with variation of location, numbers and depths of anchor blocks as well as depth of poles to find stresses acting on concrete electric poles. The stresses of concrete poles are relaxed at 600~700[kg] of tensile load, and stresses are concentrated at top of pole, and spread to lower part of pole. In the concrete pole collapse test, tensile load at failure was approximately 1,400[kg], which is twice of design load. As passive zone in the soil increases, the stresses acting on concrete pole are concentrated at lower part of pole based on moment arm earth pressure distribution.

• Proceedings of the ESK Conference
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• 1994.04a
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• pp.124-135
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• 1994

A biomechanical model of lower extremity in seated postures was developed to assess muscular activities of lower extremity involved in a variety of foot pedal operations. It is found that nonlinear optimization method which has been used for modeling the articulated body segments does not predict the forces generated from biarticular muscles reasonably, so the revised nonlinear optimization scheme was employed to consider the synergistic effects of biarticular muscles in the model, assuming that the muscle forces are distributed proportionally based on their physiological cross sectional area and moment arm. The model incorporated four rigid body segments with the nine muscles to represent lower extreimity. For the model valida- tion, three male subjects performed the experiments in which EMG activities of the nine lower extremity muscles were measured. Predicted muscle forces were compared with the corresponding EMG amplitudes and it showed no statistical difference. The developed model can be used to design and to assess the pedals and foot-related equipments design.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.5
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• pp.855-861
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• 1989

An inertia redistribution technique for liberalizing and reducing the complexity of manipulator dynamics with a parallel drive mechanism is presented in this paper. The dynamic design method is based on eliminating nonlinear terms, such as Coriolis, centrifugal and gravity torque in the kinetic and the potential energy of a manipulator. A set of design criteria regarding the inertia properties of links is derived. The resulting manipulator dynamics can be greatly simplified for each robot. This paper particularly presents that it is possible to completely linearize the manipulator dynamics with a parallel drive mechanism.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.1229-1234
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• 2001

There are three items, which are panhead displacement, tilting angle of pan head, required moment of main shaft, which representing kinematic performance of pantograph. Kinematic variables effective on kinematic performance are length of each components and installation angle, In this study, cost function is defined with 3 items, By this cost function, length of thrust rod was optimized. Finite element analysis was used to consider structural soundness. Finite element model was qualified by comparison between analysis result with experiment result. By qualified F.E, model various severe condition was simulated to consider structural soundness.

• Asia-Pacific Journal of Business
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• v.10 no.4
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• pp.197-204
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• 2019

The transfer pricing mechanism is a tool commonly used to transfer the tax base from countries with high taxation in countries with low taxation. In many countries, this financial operations generate significant tax revenue losses. In an attempt to limit tax revenue losses, many public authorities have introduced regulations on transfer pricing, but the effectiveness of these rules has proved limited, and they contributed to the increasing complexity of tax laws and to the appearance of additional costs for companies. Historically, transfer pricing (TP) was not a substantial issue in Mongolia. The tax legislation contains basic TP rules, but there is limited guidance and enforcement in practice. At the moment, Mongolian tax authorities are not conducting specific transfer pricing audits. Nevertheless, tax authorities are starting to pay more attention to transactions between related parties and potential transfer pricing adjustments. This study examines a transfer pricing regulations of Mongolia.

• Clinics in Shoulder and Elbow
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• v.24 no.3
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• pp.178-182
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• 2021

A 50-year-old woman who had been previously diagnosed with systemic lupus erythematosus consulted our clinic for pain and weakness in her right shoulder. On examination, she had an atrophied deltoid muscle, a painful right shoulder on movement, and a tender mass in the deltoid area. The patient was diagnosed with corticosteroid-induced deltoid myopathy, shoulder pain, and loss of range of motion that did not resolve with conservative treatment. We decided to perform reverse shoulder arthroplasty. No complications were observed at the last follow-up visit at 3 years postoperative. Unlike deltoid insufficiency that results from axillary nerve injury, deltoid myopathy due to corticosteroid use contains intact fibers,. Therefore, we increased the effectivity of the remaining deltoid fibers by extending the moment arm of the anterior fibers using reverse shoulder arthroplasty and achieved reliable improvements in clinical symptoms and function without increasing the risk of dislocation.

• The Journal of Korean Physical Therapy
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• v.18 no.6
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• pp.1-11
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• 2006

Purpose: This study compared the effects of non-cold and cold conditions on the viscoelastic properties of tendon structures in vivo. Methods: Seven male subjects perfomed plantar flesion exercise with maximal isokinetic voluntary contraction, which consisted of muscle contraction for 6 see and relaxation for 60 secs, 10 times for 1 set, Totally 10 sets were repeated. Before and after each task, the elongation of the tendon and aponeurosis of the medial gastrocnemius muscle (MG) was directly measured by ultrasonography. (The relationship between the estimated tendon force and tendon elongation.) Tendon cross-sectional area and ankle joint moment arm were obtained from magnetic resonance imaging (MRI). The tendon force was calculated from the joint moments and the tendon moment arm and stress was obtained by dividing force by cross-sectional areas (CSA). The strain was measured from the displacements normalized to tendon length. Results: After cooling, the tendon force was larger in cold than non-cold. The value of the tendon stiffness of MVC were significantly higher under the cold condition than under the non-cold condition. The maximal strain and stress of $7.4{\pm}0.7%$ and $36.4{\pm}1.8$ MPa in non-cold and $7.8{\pm}8.5%,\;31.8{\pm}1.1$ MPa in cold (P<0.05). Conclusion: This study shows for the first time that the muscle endurance in cooling increases the stiffness and Young's modulus of human tendons. The improvement in muscle endurance with cooling was directly related to muscle and tendon.

• Journal of the Korean Society of Marine Environment & Safety
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• v.30 no.2
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• pp.176-183
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• 2024

Assessing the stability of small fishing vessels is important to prevent capsize accidents in coastal waters that primarily occur on small fishing vessels. However, the regulations regarding stability assessment for small vessels under 24 m are inadequate according to the domestic Fisheries Act. Based on safety standards issued by the Ministry of Oceans and Fisheries in 2022 to enhance safety and welfare, vessels adhering to the enhanced safety standards for standard ship types are required to establish stability regardless of their length. This study aims to utilize these aforementioned standards to assess the stability of vessels under 24 m, investigating the suitability of applying these criteria to these vessels and examining the impact on various small vessels with different superstructures. Initially, a 4.99-ton fishing vessel designed according to the standard ship type was selected as the subject vessel. Compliance with the standards was evaluated based on the initial stability of the vessel using the transverse metacentric height (GM) and transverse restoring moment arm at the limit angle (GZ_α). Additionally, six types of small vessels with identical hull forms and specifications to the subject vessel were further examined using prevalent superstructure designs in small fishing vessels. The stability of the subject small vessel was also assessed. A study of a 4.99-ton standard fishing vessel confirmed that the safety standards for standard fishing vessels with enhanced safety welfare were applicable to small fishing vessels under 4.99-ton class and that the stability of small fishing vessels with superstructure modifications was not significantly changed.

• Korea-Australia Rheology Journal
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• v.14 no.1
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• pp.33-45
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• 2002

Recent results obtained for the port-pom model and the constitutive equations with time-strain separability are examined. The time-strain separability in viscoelastic systems Is not a rule derived from fundamental principles but merely a hypothesis based on experimental phenomena, stress relaxation at long times. The violation of separability in the short-time response just after a step strain is also well understood (Archer, 1999). In constitutive modeling, time-strain separability has been extensively employed because of its theoretical simplicity and practical convenience. Here we present a simple analysis that verifies this hypothesis inevitably incurs mathematical inconsistency in the viewpoint of stability. Employing an asymptotic analysis, we show that both differential and integral constitutive equations based on time-strain separability are either Hadamard-type unstable or dissipative unstable. The conclusion drawn in this study is shown to be applicable to the Doi-Edwards model (with independent alignment approximation). Hence, the Hadamardtype instability of the Doi-Edwards model results from the time-strain separability in its formulation, and its remedy may lie in the transition mechanism from Rouse to reptational relaxation supposed by Doi and Edwards. Recently in order to describe the complex rheological behavior of polymer melts with long side branches like low density polyethylene, new constitutive equations called the port-pom equations have been derived in the integral/differential form and also in the simplifled differential type by McLeish and carson on the basis of the reptation dynamics with simplifled branch structure taken into account. In this study mathematical stability analysis under short and high frequency wave disturbances has been performed for these constitutive equations. It is proved that the differential model is globally Hadamard stable, and the integral model seems stable, as long as the orientation tensor remains positive definite or the smooth strain history in the flow is previously given. However cautious attention has to be paid when one employs the simplified version of the constitutive equations without arm withdrawal, since neglecting the arm withdrawal immediately yields Hadamard instability. In the flow regime of creep shear flow where the applied constant shear stress exceeds the maximum achievable value in the steady flow curves, the constitutive equations exhibit severe instability that the solution possesses strong discontinuity at the moment of change of chain dynamics mechanisms.