• Proceedings of the Technology Innovation Conference
• /
• 2006.02a
• /
• pp.5-20
• /
• 2006

An efficient and productive R&D operation is a major source of competitive advantage in today's economy, and a lot of efforts are made to raise R&D productivity. A prerequisite for making R&D more efficient and productive is to be able to measure it. Hence, a number of studies have attempted to measure R&D productivity. R&D productivity, in the previous studies, was measured with patents at the firm or industry level. However, most previous studies considered only a quantitative aspect, not a quantitative aspect of patents. In this study, various dimensions of patent quality as well as patent quantity were considered for the measurement of R&D performance. The differences in R&D performance across sectors were examined, and it was found that electrical/electronic industry shows higher R&D performance than mechanic and chemical industries. Discriminant analysis based on inputs and outputs for R&D shows' that there exist a strong discriminatory power across industries. The results of this research can provide the directions 'for the firm's R&D policy.

• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10b
• /
• pp.1436-1440
• /
• 1996

The wear mechanism of material is an important mechanic property to select a material's life and a optimum work condition. Although there are many researches about a wear mechanism of material, the pin-on-disc type tribotester is widely known to us. It is difficult to add a variable and heavy load in the existing pin-on-disc type tribotester to estimate this wear mechanism. And due to a rotation of a disc, it is impossible to add a constant force. But we can solve this problem by using a hydraulic servo system. Therefore, in order to investigate a wear mechanism of materials, it is necessary to design a hydraulic pin-on-disc type tribotester and construct a controller against a variable disturbance.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2008.03a
• /
• pp.153-158
• /
• 2008

In this study, piping and slope stabilities of sea dike were analyzed through pore pressure-mechanic coupled analysis. Through decrement of sea dike inclination, to confirmed cross-section reduction possibility of multi-function sea dike.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2006.03a
• /
• pp.1312-1319
• /
• 2006

This thesis studied the scale effects on bearing capacity and settlement characteristics by using FEM. The conclusions of the study are as follows. 1) For sandy soil, the bearing capacity ratio increased in the form of logarithm as the foundation width increased. Hence application of static mechanic theory results in overestimation of the bearing capacity when the bearing capacity should be derived from plate loading test results. 2) In clayey soil, the characteristics of the bearing capacity associated with foundation width met Terzaghi's bearing capacity theory. 3) In sandy soil, the settlement ratio increased non-linearly as foundation width increased. However, in clayey soil, the settlement ratio increased linearly. 4) In ordinary soil, the foundation width - settlement ratio turned out to be close to that of sandy soil.

• 제어로봇시스템학회:학술대회논문집
• /
• 2001.10a
• /
• pp.170.1-170
• /
• 2001

This paper developed the model for electro hydraulic force control system by identification method via ARMAX model. Implementation of Identification is performed on Pin-On-Disk type tribotester. The wear mechanism is an important mechanic property to select a material´s life and a optimum work condition. Pin-on-disk type tribotester is popular wear analysis experimental equipment and its mechanism is that adding a force on a rotating disk to simplify two surface contact´s wear experimental condition. Material´s rotating velocity and eccentricity rotation makes disturbance and it affects adding constant force. To get a high performance of force adding part, DDV(Direct Drive Valve) which has pressure control loop is used. To obtain a tribotester´ s ARMAX model, prediction error method(PEM) is used in case force adding part and rotating part is ...

• Tuberculosis and Respiratory Diseases
• /
• v.79 no.3
• /
• pp.188-192
• /
• 2016

Antisynthetase syndrome has been recognized as an important cause of autoimmune inflammatory myopathy in a subset of patients with polymyositis and dermatomyositis. It is associated with serum antibody to aminoacyl-transfer RNA synthetases and is characterized by a constellation of manifestations, including fever, myositis, interstitial lung disease, mechanic's hand-like cutaneous involvement, Raynaud phenomenon, and polyarthritis. Lung disease is the presenting feature in 50% of the cases. We report a case of a 60-year-old female with acute respiratory distress syndrome (ARDS), which later proved to be an unexpected and initial manifestation of anti-Jo-1 antibody-positive antisynthetase syndrome. The present case showed resolution of ARDS after treatment with high-dose corticosteroids. Given that steroids are not greatly beneficial in the treatment of ARDS, it is likely that the improvement of the respiratory symptoms in this patient also resulted from the prompt suppression of the inflammatory systemic response by corticosteroids.

• Journal of the Korean Society of Costume
• /
• v.53 no.7
• /
• pp.125-137
• /
• 2003

This study is to explore the Post-modern fashion image appeared in the costumes of the movie $\ulcorner$Matrix2-Reloaded$\lrcorner$, which is believed to adapt successfully the Postmodernism ideas on screen. From this study, we can find that the movie costumes express certain formative characteristics considerably affected by the contemporary fashion trends such as Minimalism, Formalism, Futurism, Ethno-eclecticism, Asexualism. These are mostly common tendencies aroused in the complex and pluralistic circumstances of Postmodernism where many diverse values are equally regarded. Finally, the 5 trends lead to represent the following symbolic meanings with entanglement in multiplex ways, that is Virtual Reality, Mechanic Artificiality, Human Dignity, Mysticism, Multi-Culturism, and Nonsexuality to create a strong unified imagery and style in that Post-modern movie.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.11 no.5
• /
• pp.13-20
• /
• 2012

In order to clarify the effect of overload on crack growth behaviors, fatigue tests for overload were carried out for round plain specimens of SM45C steel. In the experiment, typical semi-elliptical crack shape was found and further crack growth behaviors were tested. Using three types of single overload fatigue tests, Crack growth retardation phenomenon were examined. The growth rate of surface crack(da/dN) during retardation period was analyzed in terms of ${\Delta}K$ and ${\Delta}K_{eff}$. On the growth rate of surface crack analyzed by ${\Delta}K$, the dependence of overload stress levels appears. However, on the growth rate by ${\Delta}K_{eff}$ obtained by Willenborg analysis, there is a non-liner relationship between da/dN and ${\Delta}K_{eff}$ with narrow scatter band.

• Coupled systems mechanics
• /
• v.7 no.1
• /
• pp.5-25
• /
• 2018

A fully-coupled thermodynamic-based transient finite element formulation is proposed in this article for electric, magnetic, thermal and mechanic fields interactions limited to the linear case. The governing equations are obtained from conservation principles for both electric and magnetic flux, momentum and energy. A full-interaction among different fields is defined through Helmholtz free-energy potential, which provides that the constitutive equations for corresponding dual variables can be derived consistently. Although the behavior of the material is linear, the coupled interactions with the other fields are not considered limited to the linear case. The implementation is carried out in a research version of the research computer code FEAP by using 8-node isoparametric 3D solid elements. A range of numerical examples are run with the proposed element, from the relatively simple cases of piezoelectric, piezomagnetic, thermoelastic to more complicated combined coupled cases such as piezo-pyro-electric, or piezo-electro-magnetic. In this paper, some of those interactions are illustrated and discussed for a simple geometry.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.18 no.4 s.70
• /
• pp.453-458
• /
• 2005

This study deals with elasto-plasticity of granular micro-structures which recovers continuum elasto-plasticity in its counterpart. The theory is based on doublet mechanics that assumes particles of finite size and connecting linear springs, and it makes extensions to plasticity. The result shows that the micro model has one to one relationship with the continuum model in the simplest case. Micro-strain and micro-stress of two dimensional plane stress problem were calculated, which shows the behavior of the specimen and verifies the effectiveness of this model.