• Journal of the Korean Society of Systems Engineering
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• v.14 no.1
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• pp.72-82
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• 2018

Generally speaking, because of complexity of engineering process, the systems engineering may be not easy to understand clearly and not easy to perform also. The status of systems engineering infrastructure of the some Korean industry is not matured yet, i.e., the systems engineering process, method, tool and environment is not implemented consistently within the steel making industry. These difficulties are more severe at the concept and basic design phase than the detail design phase relatively. Korean industry has lots of development project for the precedented systems and usually has matured domain knowledge for the precedented systems. Even though there is a mature domain knowledge of the precedented systems, the development project will lead to failure under the condition of engineering system is not well equipped. For the project success, it is very important to have a proper engineering execution system especially for the concept design and basic phase, which has a high abstraction and a large influence on the whole project. This paper proposes a minimized design process that can be easily applied to the concept and basic design phase of the precedented systems, instead of complex system engineering processes. This paper also proposes the application case of the minimized design process and methods for a Blast Furnace System.

• Journal of the Korean Society of Groundwater Environment
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• v.1 no.2
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• pp.90-99
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• 1994

Heterogeneous hydraulic conductivity in a flow domain is generated under the assumption that it is a random variable with a lognormal, spatially-correlated distribution. The hydraulic head and the conductivity in a groundwater flow system are represented as a stochastic process. The method of Monte Carlo Simulation (MCS) and the finite element method (FEM) are used to determine the statistics of the head and the logconductivity. The second moments of the head and the logconductivity indicate that the cross-covariance of the logconductivity with the head has characteristic distribution patterns depending on the properties of sources, boundary conditions, head gradients, and correlation scales. The negative cross-correlation outlines a weak-response zone where the flow system is weakly responding to a stress change in the flow domain. The stochastic approach has a potential to quantitatively delineate the zone of influence through computations of the cross-covariance distribution.

• Wind and Structures
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• v.11 no.2
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• pp.75-96
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• 2008

A better understanding of tornado-induced wind loads is needed to improve the design of typical structures to resist these winds. An accurate understanding of the loads requires knowledge of near-ground tornado winds, but observations in this region are lacking. The first goal of this study was to verify how well a CFD model, when driven by far field radar observations and laboratory measurements, could capture the flow characteristics of both full scale and laboratory-simulated tornadoes. A second goal was to use the model to examine the sensitivity of the simulations to various parameters that might affect the laboratory simulator tornado. An understanding of near-ground winds in tornadoes will require coordinated efforts in both computational and physical simulation. The sensitivity of computational simulations of a tornado to geometric parameters and surface roughness within a domain based on the Iowa State University laboratory tornado simulator was investigated. In this study, CFD simulations of the flow field in a model domain that represents a laboratory tornado simulator were conducted using Doppler radar and laboratory velocity measurements as boundary conditions. The tornado was found to be sensitive to a variety of geometric parameters used in the numerical model. Increased surface roughness was found to reduce the tangential speed in the vortex near the ground and enlarge the core radius of the vortex. The core radius was a function of the swirl ratio while the peak tangential flow was a function of the magnitude of the total inflow velocity. The CFD simulations showed that it is possible to numerically simulate the surface winds of a tornado and control certain parameters of the laboratory simulator to influence the tornado characteristics of interest to engineers and match those of the field.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.15 no.2
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• pp.209-218
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• 2002

The Vector Random Decrement technique has been developed as an efficient method for transforming ambient responses into free decays of linear structures. It is shown that the VRD functions nay contain as much information about the modes as the really measured free decay responses. In this paper, the theory of the VRD technique is extended by applying the concept of the mode shape ratio into the Ibrahim Time Domain modal parameter identification algorithm. The VRD function is not shifted in the correction procedures for constant time shifts of the proposed VRD technique. Thus, a number of points equal to the largest of the time shifts used in the vector triggering condition are not deleted. In the VRD functions, any influence of the input to the system is averaged out. The proposed technique is compared with the traditional VRD technique by assessment of the modal parameters. The applicability of the VRD technique has been justified through a simulation study and a study of the response of a laboratory beam model subject to ambient loads.

• The Journal of Internal Korean Medicine
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• v.19 no.2
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• pp.7-16
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• 1998

Background and Purpose The increasing evidence for neurally mediated cardiac damage and sudden death has focused attention on the central autonomic control of cardiac function. Power spectral analysis of heart rate variability(HRV) can detect autonomic consequences of stroke. We performed power spectral analysis of heart rate variability from 24-hour holter recording to identify cerebral hemispheric lateralization and gender effect in cardiac autonomic control. Methods Data were obtained from 24-hour holter recordings in 30 consecutive patients with hemispheric brain infarction in the subacute phase. We analysed the time domain and frequency domain measures of HRV and ST segment by hemispheric lateralization and Gender. Results ST segment was depressed in women compared with man. There was no statistically significant differences between right and left hemisphere stroke patients in any standard index of HRV and ST segment changes. Conclusions These data are partial consistent with evidence from the recent literature that two cerebral hemispheres and gender have a differential influence on the nature and severity of cardiac dysfunction. We think the prospective and definite study was necessary.

• Wind and Structures
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• v.14 no.3
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• pp.187-208
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• 2011

Based on the ANSYS, an approach of full-mode aerodynamic flutter analysis for long-span suspension bridges has been presented in this paper, in which the nonlinearities of structure, aerostatic and aerodynamic force due to the deformation under the static wind loading are fully considered. Aerostatic analysis is conducted to predict the equilibrium position of a bridge structure in the beginning, and then flutter analysis of such a deformed bridge structure is performed. A corresponding computer program is developed and used to predict the critical flutter wind velocity and the corresponding flutter frequency of a long-span suspension bridge with double main span. A time-domain analysis of the bridge is also carried out to verify the frequency-domain computational results and the effectiveness of the approach proposed in this paper. Then, the nonlinear effects on aerodynamic behaviors due to aerostatic action are discussed in detail. Finally, the results are compared with those of traditional suspension bridges with single main span. The results show that the aerostatic action has an important influence on the flutter stability of long-span suspension bridges. As for a suspension bridge with double main spans, the flutter mode is the first anti-symmetrical torsional vibration mode, which is also the first torsional vibration mode in natural mode list. Furthermore, a double main-span suspension bridge is better in structural dynamic and aerodynamic performances than a corresponding single main-span structure with the same bridging capacity.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.7 s.100
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• pp.788-798
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• 2005

The monopole theory has long been used to model air-pumped effect from the elastic cavities in car tire. This approach models the change of an air as a Piston moving backward and forward on a spring and equates local air movements exactly with the volume changes of the system. Thus, the monopole theory has a restricted domain of applicability due to the usual assumption of a small amplitude acoustic wave equation and acoustic monopole theory This paper describes an approach to predict the air-pumping noise of a car tyre with CFD/Kirchhoff integral method. The tyre groove is simply modeled as piston-cavity-sliding door geometry and with the aid of CFD technique flow properties in the groove of rolling car tyre are acquired.'rhese unsteady flow data are used as a air-pumping source in the next CFD calculation of full tyre-road geometry. Acoustic far field is predicted from Kirchhoff integral method by using unsteady flow data in space and time which is provided by the CFD calculation of full tyre-road domain. This approach can cover the non-linearity of acoustic monopole theory with the aid of Non-linear governing equation in CFD calculation. The method proposed in this paper is applied to the prediction of air-pumping noise of simply modeled car tyre and through the predicted results, the influence of nonlinear effect on air-pumping noise propagation is investigated.

• Korean Journal of Human Ecology
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• v.5 no.2
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• pp.37-52
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• 1996

The purpose of this study was to explore the nature of parent education programs for fathers with children aged 1 through 5 year-old. One-Hundred forty-four fathers were answered using questionaire designed to elicit their perception of fathering, the details of domain parent education, and parent education program. Data were analyzed quantitatively and qualitatively to determine the contents of parent education program as perceived by the fathers. The results of this study were as follows; 1. Fathers perceived about parent education as 'The training of living behavior', 'The education about essential method of living manners and the guidance for children.' Also, fathers commented some difficult points of raising children as; 'children' sickness', 'Parents' permission or control', and 'Childrens' stubborness'. Many fathers pointed their shortages; 'to be a model of habit and behavior', 'Lacking of enough experience and imagination to their children', and 'Limiting parent's patience to their children'. 2. On the domain of parent education, six subscales of requisite degree was very high. The highest requisite domains like three questions of 34 subordinate question was; 'to encourage their children their children', knowledge about how to develop children' emotions', 'knowledge of their influence to their children' humanity'. 3. Fathers answered that a parent education was needed in infant period. They choose suitable time and place, from p.m.6 to p.m. 9 on a day and once in a week in the kindergarten. Also, the contents of parent education program were needed in order as follows; 'Communication method with a child', 'Formation of living behavior'. Moreover, 77.6% of fathers wanted to participate in the parent education program.

• Journal of the Korean Society of Costume
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• v.54 no.2
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• pp.105-119
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• 2004

Cultural hybridization and global cross-fertilization, begun since the 1990s, mean the hybrid mixture of the low-class popular arts and the high-class fine arts and have found expression in intertextuality by means of the thinking system of de-constructuralist post-modernism. This study was intended to investigate the artistic intertextuality between fashion and art frontiere, especially between such fields as 'animation', 'music', and 'performing arts' and 'fashion', which shows the greatest characteristic of the phenomenon that the non-mainstream culture flows into the mainstream culture. It also aimed to investigate the intertextuality between 'technology' and 'fashion' as the delivery room of the youth culture and copycat culture due to the benefit of technologies since the 20th-century digital revolution. Animation as the neo-pop art with the popular code coming to the forefront in the 21th century integrated high-class fashion and low-class fashion into one through the combination of fashion and humor, and the musical element referring to the social difference of the cultural field and the social strata is becoming the 21th-century fashion icon through its fusion with the pictorial tendency along with the leisure-time life of the non-mainstream strata. In terms of intertextuality in performing arts, fashion style performs an important role in the presentation of performing arts and since the de-construction of the fin-de-ciecle form and its fusion with media have taken place, fashion works become and element of the origin that has an influence on a series of film, dance, dramatic elements and the like. The paradigm of technology made it socially and culturally possible to achieve the architecture of clothing system necessary for fashionable technical clothing by allowing the possibility of imitation, the function of technology to form popular culture. The intertextual tendency in the 21th-century fashion began from the de-constructive phenomenon of existing norms and now takes the multicultural character of surpassing a certain domain or concept. And it positions itself as the total art of spearheading the low-class culture and the non-mainstream culture as the hybrid domain of mainstream and non-mainstream cultures or high-class and low-class cultures.

• Korean Journal of Animal Reproduction
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• v.25 no.4
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• pp.381-388
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• 2001

The present study was designed to obtain porcine growth hormone binding protein (pGHBP) improved biological activation as derived mutation in binding site with growth horlnone (GH). A 756 bp of fragment encoding the extracellular domain of pGHBP gene was cloned from the total RNA of porcine fat tissue by reverse transcriptase polymerase chain reaction (RT-PCR) and created mutation in positions 26 and 122 using site-directed mutagenesis method. Position 26 is one and it is near to get on five potential N-linked glycosylation sites located in the extracellular domain of porcine growth hormone receptor known to have a direct influence on combination with GH. Position 122 is known as one of conformational epitope in bovine. It was over-expressed in E. coli using pET-32(c) expression vector and precisely purified by S-protein agarose and enterokinase. In our results, we was obtained pmGHBP of 30 kDa. It suggests to study the effects of the pmGHBP on cell proliferation in vitro and growth rate in vivo after administration.