• Smart Structures and Systems
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• v.15 no.6
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• pp.1463-1479
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• 2015

Lamb waves have been a promising candidate for quantitative damage identification for various engineering structures, taking advantage of their superb capabilities of traveling for long distances with fast propagation and low attenuation. However, the application of Lamb waves in damage identification so far has been hampered by the fact that the characteristic signals associated with defects are generally weaker compared with those arising from boundary reflections, mode conversions and environmental noises, making it a tough task to achieve satisfactory damage identification from the time series. With awareness of this challenge, this paper proposes a time reversal-based technique to enhance the strength of damage-scattered signals, which has been previously applied to bulk wave-based damage detection successfully. The investigation includes (i) an analysis of Lamb wave propagation in a plate, generated by PZT patches mounted on the structure; (ii) an introduction of the time reversal theory dedicated for waveform reconstruction with a narrow-band input; (iii) a process of enhancing damage-scattered signals based on time reversal focalization; and (iv) the experimental investigation of the proposed approach to enhance the damage identification on a composite plate. The results have demonstrated that signals scattered by delamination in the composite plate can be enhanced remarkably with the assistance of the proposed process, benefiting from which the damage in the plate is identified with ease and high precision.

• Journal of Families and Better Life
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• v.28 no.2
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• pp.63-76
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• 2010

A law facilitating a family-friendly social environment was legislated in December 2007. According to the law, projects for facilitating a family-friendly social environment consisted of a family-friendly working environment, a community environment, and the promotion of a family-friendly culture. There has been much progress in developing a family-friendly working environment through projects such as those advocating for flexible work hours, an employee support system, and child care and a family care support system. However, in terms of a family-friendly community environment project, there was no noticeable advancement. Hence, this study was conducted to find ways to vitalize the family-friendly village project in terms of the family-friendly community environment project. The major findings of this study were as follows: A family-friendly village could be structured on the three axes of time, space, and relation. The model of the family-friendly village project consists of the following three steps: motivation, systematization, and participating & practicing. In the motivation step, integration, community, and sustainability were needed as basic ideologies for a family-friendly village. In the systematization step, providing systematic educational systems for residents taking on leadership and activist roles was stressed. In the participating & practicing step, many ways to facilitate residents' social relationships were suggested: starting the project from matters of common interests, making the resolution of families' problems a communal task of the residents, accepting the opinions of various groups associated with the matter, and taking a differentiated project process according to the geographic, socio-economic, and demographic characteristics of the groups. It is strongly suggested that the family-friendly village should be taken as a common functional scheme in everyone of eight livable village models because a key factor in a family-friendly village, family care, serves an essential function in any livable village model.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.05a
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• pp.786-789
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• 2015

Recent concept of smart wort which is advanced from that of existing smart work means the task performance method in which we can provide the highest value to our customers by accomplishing the customer-oriented business creatively, innovatively and quickly. New concept of smart work can come through adding multiple intelligence theory and open innovation to social media technologies which have the characteristics of high connectivity, collective intelligence, rapid feedback. In accordance with the evolution of smart work concept, it is necessary to make the plan and strategy on R&D and standardization through the analysis of key technologies in order to realize the advanced smart work and secure a leading position in smart work market. Accordingly, In this paper, we propose standardization tasks and technologies which our country can lead and present a long-term driving directions by analyzing the conceptual change of smart work, technology trends and standardization trends.

• Korean Journal of Construction Engineering and Management
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• v.6 no.5 s.27
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• pp.110-118
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• 2005

This paper examines the method of evaluation for feasibility study factors on housing development projects which can assist project managers to asses potential sources of risk. The aim is to reduce uncertainty on the project objectives. The major initial goals for a feasibility analysis are to define a limited set of key related factors which apply to housing development project according to development and market environment, condition of project planning and economics. Thus, in order to construct types of factors related with the feasibility, the research executes Delphi Method subjected personnel in the task to explore housing development projects. Such exploration provide the information for Importance Index, Extra Weight and the Mean of Extra Weight that is used for constituting confines of factors related with a feasibility analysis.

• Journal of The Korean Astronomical Society
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• v.38 no.4
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• pp.463-470
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• 2005

In this paper, we have made the component-based development of observational software for KASI solar imaging spectrograph (KSIS) that is able to obtain three-dimensional imaging spectrograms by using a scanning mirror in front of the spectrograph slit. Since 2002, the KASI solar spectrograph has been successfully operated to observe solar spectra for a given slit region as well as to inspect the response functions of narrow band filters. To improve its capability, we have developed the KSIS that can perform sequential observations of solar spectra by simultaneously controlling the scanning mirror and the CCD camera via Visual C++. Main task of this paper is to introduce the development of the component-based software for KSIS. Each component of the software is reusable on the level of executable file instead of source code because the software was developed by using CBD (component-based development) methodology. The main advantage of such a component-based software is that key components such as image processing component and display component can be applied to other similar observational software without any modifications. Using this software, we have successfully obtained solar imaging spectra of an active region (AR 10708) including a small sunspot. Finally, we present solar $H{\alpha}$ spectra ($6562.81{\AA}$) that were obtained at an active region and a quiet region in order to confirm the validity of the developed KSIS and its software.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.4
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• pp.15-25
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• 1993

In order to promote the efficient use of composite materials, effort is currently being directed at the development of design criteria for composite structures. Insofar as design against buckling is concerned, it is well known that, for metal shells, a key step is the definition of 'knockdown' factors on the elastic critical buckling stress accounting mainly for the influence of initial geometric imperfections. At present, the imperfection sensitivity of composite shells has not been explored in detail. Due to the large number of parameters influencing buckling response (considerably larger than for isotropic shells), a very large number of tests would be needed to quantify imperfection sensitivity experimentally. An alternative approach is to use validated numerical models for this task. Thus, the objective of this paper is to outline the underlying theory used in developing a composite shell element and to present results from a validation exercise and subsequently from a parametric study on axially loaded glass fibre-reinforced plastic (GFRP) curved panels using finite element modelling. Both eigenvalue and incremental analyses are performed, the latter including the effect of initial geometric imperfection shape and amplitude, and the results are used to estimate 'knockdown' factors for such panels.

• Proceedings of the KSPS conference
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• 1996.10a
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• pp.472-472
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• 1996

The material of database for speech recognition should include phonetic phenomena as much as possible. At the same time, such material should be phonetically compact with low redundancy[1, 2]. The phonetic phenomena in continuous speech is the key problem in speech recognition. This paper describes the processing of a set of sentences collected from the database of 1993 and 1994 "People's Daily"(Chinese newspaper) which consist of news, politics, economics, arts, sports etc.. In those sentences, both phonetic phenometla and sentence patterns are included. In continuous speech, phonemes always appear in the form of allophones which result in the co-articulary effects. The task of designing a speech database should be concerned with both intra-syllabic and inter-syllabic allophone structures. In our experiments, there are 404 syllables, 415 inter-syllabic diphones, 3050 merged inter-syllabic triphones and 2161 merged final-initial structures in read speech. Statistics on the database from "People's Daily" gives and evaluation to all of the possible phonetic structures. In this sentence set, we first consider the phonetic balances among syllables, inter-syllabic diphones, inter-syllabic triphones and semi-syllables with their junctures. The syllabic balances ensure the intra-syllabic phenomena such as phonemes, initial/final and consonant/vowel. the rest describes the inter-syllabic jucture. The 1560 sentences consist of 96% syllables without tones(the absent syllables are only used in spoken language), 100% inter-syllabic diphones, 67% inter-syllabic triphones(87% of which appears in Peoples' Daily). There are rougWy 17 kinds of sentence patterns which appear in our sentence set. By taking the transitions between syllables into account, the Chinese speech recognition systems have gotten significantly high recognition rates[3, 4]. The following figure shows the process of collecting sentences. [people's Daily Database] -> [segmentation of sentences] -> [segmentation of word group] -> [translate the text in to Pin Yin] -> [statistic phonetic phenomena & select useful paragraph] -> [modify the selected sentences by hand] -> [phonetic compact sentence set]

• Korean Medical Education Review
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• v.18 no.3
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• pp.125-131
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• 2016

Recent changes in educational paradigms that emphasize the performance or outcomes of education are redefining how learning objectives are being described as 'learning outcomes' in various academic disciplines. Medical education is not an exception to this trend. However, it has come to our attention that the key concepts and appropriate descriptions of learning outcomes have not been well understood among educators and that this lack of understanding has hindered our efforts to implement the practice in the field. This study aims to provide a direction to establish and describe learning outcomes by examining previous studies that have focused on setting learning objectives as well as learning outcomes. Setting and describing learning outcomes starts from reflection on the approach of behavioral learning objectives, which overemphasizes learner's acquired knowledge, skills, and attitude in each classroom rather than actual performance. On the other hand, the learning outcome approach focuses on what the learner is able to do as a result of a learning experience. This approach is more learner-friendly and encourages students to lead and be responsible for their learning process. Learning outcomes can best be described when the relevance of actual contexts and the hierarchy of learning objectives are considered. In addition, they should be in the form of context, task, performance, and level, as well as be planned with proper assessment and feedback procedures. When these conditions are met, the learning outcome approach is beneficial to students as it presents a curriculum that is more open to learners. Despite these advantages of the learning outcome approach, there is a possible concern that setting the learning outcomes and describing them can restrict evaluation to lower cognitive skills if the concept of learning outcome is narrowly interpreted or is set too low. To avoid such narrow applications, it is important for educators to understand the comprehensiveness of the learning outcome setting and to consider long-term outcomes embedded in an organizational vision rather than only short-term behavioral outcomes.

• Journal of Korea Multimedia Society
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• v.16 no.4
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• pp.493-501
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• 2013

A key challenge in massively multiplayer on-line game(MMOG) systems is providing real-time response latencies to the large number of concurrent game players. MMOG systems are a kind of soft real-time systems because requests from many players should be responded within specified time constraints. Client events have different timeliness and consistency requirements according to their nature in the game world. These requirements lead to tasks with different priorities on CPU processing. In order to meet their timing constraints, we propose priority scheduling methods that attempt to allocate preferentially more CPU bandwidth to serve an task with the higher priority level in the presence of transient overloading. The proposed scheduling methods are capable of enhancing real-time performance of MMOG system by maximizing the number of tasks with higher priority completed successfully within their deadlines while minimizing total average latency of tasks finished after given deadlines. The performance of these scheduling methods is evaluated through extensive simulation experiments.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.6
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• pp.767-777
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• 2014

Characterizing local chicken types and their mostly rural production systems is prerequisite for designing and implementing development and conservation programs. This study evaluated the management practices of small-scale chicken keepers and the phenotypic and production traits of their chickens in Oman, where conservation programs for local livestock breeds have currently started. Free-range scavenging was the dominant production system, and logistic regression analysis showed that socio-economic factors such as training in poultry keeping, household income, income from farming and gender of chicken owners influenced feeding, housing, and health care practices (p<0.05). A large variation in plumage and shank colors, comb types and other phenotypic traits within and between Omani chicken populations were observed. Male and female body weight differed (p<0.05), being $1.3{\pm}0.65$ kg and $1.1{\pm}0.86$ kg respectively. Flock size averaged $22{\pm}7.7$ birds per household with 4.8 hens per cock. Clutch size was $12.3{\pm}2.85$ and annual production $64.5{\pm}2.85$ eggs per hen. Egg hatchability averaged $88{\pm}6.0%$ and annual chicken mortality across all age and sex categories was $16{\pm}1.4%$. The strong involvement of women in chicken keeping makes them key stakeholders in future development and conservation programs, but the latter should be preceded by a comprehensive study of the genetic diversity of the Omani chicken populations.