• Proceedings of the CALSEC Conference
• /
• 2003.09a
• /
• pp.45-53
• /
• 2003

This paper addresses the issues related to the development of product model and applications fer nuclear power plants based on STEP and PLIB standards. The ISO standards which can be applied are; STEP(Standard for the Exchange of Product Model Data) AP(application protocol) 221/231, AP 230/225, AP 227, ISO 13584 PLIB, ISO 15926 RDL. The data models of the AP's and ISO 15926 RDL are reviewed and an application system is proposed to exchange and share the design data of the nuclear power plant.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2001.10c
• /
• pp.103-122
• /
• 2001

For prediction of ground movement per the excavation step, observational results of ground movement during the construction was very different with prediction during the analysis of design. step because of the uncertainty of the numerical analysis modelling, the soil parameter, and the condition of a construction field, etc. however accuratly numerical analysis method was applied. Therefore, the management system through the construction field measurement should be achieved for grasping the situation during the excavation. Until present, the measurement system restricted by ‘Absolute Value Management system’only analyzing the stability of present step was executed. So, it was difficult situation to expect the prediction of ground movement for the next excavation step. In this situation, it was developed that ‘The Management system TOMAS-EXCAV’ consisted of ‘Absolute value management system’ analyzing the stability of present step and ‘Prediction management system’ expecting the ground movement of next excavation step and analyzing the stability of next excavation step by‘Back Analysis’. TOMAS-EXCAV could be applied to all uncertainty of earth retaining structures analysis by connecting ‘Forward analysis program’ and ‘Back analysis program’ and optimizing the main design variables using SQP-MMFD optimization method through measurement results. The application of TOMAS-EXCAV was confirmed that verifed the three earth retaing construction field by back analysis.

• 한국초전도학회:학술대회논문집
• /
• v.10
• /
• pp.146-150
• /
• 2000

Two methods have been investigated to fabricate good quality step-edge Josephson junctions on STO, MgO, and LAO single crystal substrates. One is the annealing of substrates at 1050$^{\circ}$C in 1 atmospheric oxygen after Ar-ion milling. The other is the cleaning of step-edge by using Ar ion milling. The step-edge is characterized with atomic force microscope (AFM) images. And YBCO thin films are deposited by using pulsed laser. The I-V properties of step-edge junctions are characterized. The yield rate of step-edge junction is increased by new fabrication methods.

• Journal of Life Science
• /
• v.31 no.4
• /
• pp.385-388
• /
• 2021

Anther cultivation for crop breeding is a method of rapid production of homozygosities by greatly reducing the time required for at least six generations to develop new varieties using conventional breeding methods. This technique of producing anther culture provides an opportunity to obtain more green plants from a methodological point of view, and the techniques that save time and effort in anther culture are also important because they increase the efficiency of culture. This study compared the callus induction rate and green plant regeneration rate of a one-step and a two-step culture that differ in their culture media and culture methods. One-step culture allows callus induction and plant regeneration in one medium, whereas two-step culture requires induction and plant regeneration in two different media. In this study, we compared the callus induction and plant regeneration rates of rice anthers as one-step and two-step cultures. The callus formation rate was 13.0% for one-step cultures and 8.6% for two-step cultures, so the rate was 4.4% higher for one-step cultures than for two-step cultures. The plant regeneration rate was 1.0% in one-step cultures and 3.0% in two-step cultures, so the regeneration rate was three times higher for the two-step cultures than for one-step cultures. This suggests that the two-step cultures are more efficient than the one-step cultures for haploid production.

• Land and Housing Review
• /
• v.7 no.3
• /
• pp.157-164
• /
• 2016

Recently, the paradigm of land development has been transformed from the joint development to the step-by-step development due to changes in socio-economic conditions. Nevertheless, the introduction of large-scale transportation facilities such as new transportation system tends to employ the joint development. Although new transportation system is eco-friendly, it occasionally fails at the beginning of the project because of high installation cost. Such phenomenon is caused by not only the system did not reflect the local characteristics but also did not respond to the step-by-step development. Accordingly, in order to introduce transportation system rationally, introducing new methods corresponding to the step-by-step development should be sought. In this study, we assumed that large-scaled land development site be achieved step-by-step development. and suggested the need for a phased introduction through benefit-cost analysis. The findings illustrated that the phased introduction shows economic efficiency with 30% increase of B/C compared to the bulk introduction. It also demonstrates that the bulk introduction under step-by-step development is more efficient than the bulk introduction under joint development.

• International Journal of Reliability and Applications
• /
• v.15 no.2
• /
• pp.85-98
• /
• 2014

Accelerated life testing (ALT) is a well famous technique in life testing and reliability studies, this is particularly used to induce so high stress leading to failure of the highly reliable units quickly under stipulated duration of time. The step-stress ALT is one of the systematic experimental strategy of ALT applied to fail the units in steps. In this article we focus on two important issues (i) necessity of life tests at higher steps with relevant causes (ii) to develop a new optimum test plan for 3-step SSALT under the modified cumulative exposure model proposed by Khamis and Higgins (1998). It is assumed that the lifetime of test units follows Rayleigh distribution and its scale parameter at constant stress level is assumed to be a log-linear function of the stress. The maximum likelihood estimates of the parameters involved in the step-stress ALT model are obtained. A simulation study is performed for numerical investigation of the proposed new optimum plan 3-step, step-stress ALT. The necessity of the life test units at 3-step step-stress is also numerically examined in comparison to simple step-stress setup.

• Journal of Korean Home Economics Education Association
• /
• v.2 no.1
• /
• pp.123-142
• /
• 1990

The aim of this study is to apply lesson design of high school home economics to model which consists of six steps of instructional procedure among various models for instructional design, Through thesis, central content of each step was written as follows; 1) At the step of establishment of terminal instructional objectives, educational objectives, terminal instructional objectives was analyzed and specific instructional objectives was extracted. 3) At the step of diagnosis of entering behavior, ability of prior learning and ability of preliminary learning were evaluated, which was used as establishing instructional strategy and doing individual guidance. 4)At the step of determining instructional strategy, instructional strategy should be extracted by considering instructional event which is adequate to content of instruction. Instructional strategy consists of five main factor, factors, those are, activity of introduction of instruction, presentation of content of instruction and information, participation of learner and learning activity, identification of learning result, and subsequent treatment after evaluation. 5)Specific activity at the step of selection and development of instructional media consists of reidentification of instructional objectives determination of learning type, drawing up instructional media analysis sheet, synthesis of selected media, and explanatory note of selected media. In order to increase efficiency of instruction at the step of determining instructional strategy, this step should be considered simultaneously. 6)The step of try-out and evaluation of instructional design should be efficient when designed instruction was inputted at class after evaluation of each step of instructional design.

• The Journal of the Acoustical Society of Korea
• /
• v.35 no.1
• /
• pp.55-62
• /
• 2016

The least-mean fourth (LMF) algorithm is well known for its fast convergence and low steady-state error especially in non-Gaussian noise environments. Recently, there has been increasing interest in the least mean square (LMS) algorithms with variable step size. It is because the variable step-size LMS algorithms have shown to outperform the conventional fixed step-size LMS in the various situations. In this paper, a variable step-size LMF algorithm is proposed, which adopts an algebraic optimal step size as a variable step size. It is expected that the proposed algorithm also outperforms the conventional fixed step-size LMF. The superiority of the proposed algorithm is confirmed by the simulations in the time invariant and time variant channels.

• PNF and Movement
• /
• v.1 no.1
• /
• pp.33-41
• /
• 2003

Objectives : The purpose of this study was to describe and compare the temporo-spatial gait characteristics of healthy young people with those of healthy elderly people. Methods: The data were collected by 40 volunteers. 20 subjects were between 20 and 31 years of age, and 20 subjects were between 65 and 84 years of age. Temporal and spatial parameters of gait were analysed for using the computerized GAITRite system. Results : The system integrates specific components of locomotion to provide a single, numerical representation of gait, the Functional Ambulation Performance score. Differences in gait characteristics between the two groups were examined using a correlated t-test(p<.05). Significant differences were observed between the groups for step length, step/extremity ratio and velocity. Young people demonstrated a significantly larger velocity, step length and step/extremity ratio than the elderly people. Conclusions: These results indicate that the GAITRite system can be useful in detecting footfall patterns and selected time and distance measurements of young and older persons. Additionaly, differences in walking velocity, step length and step/extremity ratio between old and young people may have influenced the gait characteristics measured.

• Korean Journal of Computational Design and Engineering
• /
• v.9 no.2
• /
• pp.175-182
• /
• 2004

As a bridge between design and manufacturing, process planning is to generate a sequenced set of instructions to manufacture the specified part. Automatic interpretation of manufacturing information incorporated in the design documentation such as CAD file has been a knotty subject for manufacturing engineers since no current data exchange format for product data provides a perfect interface between heterogeneous systems. The recent neutral data exchange format STEp, standard for the exchange of product model data, includes not only geometry but also technical and managerial information. STEP AP(Application Protocol) 224 is specifically dedicated to the mechanical product definition for process planning using machining features. Given a design information in STEP AP 224 format, process planning can be made without human intervention. This paper describes a method to determine the sequence of machining features by using the machining features and the manufacturing information expressed in STEP AP224.