• Proceedings of the KSME Conference
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• 2000.04a
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• pp.67-72
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• 2000

Demand for now nondestructive evaluation are growing to detect fatigue crack growth behavior to predict long term performance of materials and structure in aggressive environments especially when they are In non-visible area. Acoustic emission technique is well suited to these problems and has drawn a keen interests because of its dynamic detection ability, extreme sensitivity and location of growing defects. In this study, we analysed acoustic emission signals obtained in fatigue and tensile test of high strength fire resistance steel for frame structure with time-frequency analysis methods. The main frequency range is different in the noise and the fatigue crack propagation. It could be classified that it were also generated by composite fracture mechanics of cleavage, dimple, inclusion separation etc.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.214-217
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• 1999

Polymeric composite insulators have been in use for outdoor insulation. However, our knowledge about their long-term performance in a outdoor environment is still very limited. Especially, these insulator are subjected to the environmental stress such as ultraviolet radiation. Hence, in this paper. the influence of UV radiation on the aging of the shed materials was evaluated. For the aging evaluation, these insulators studied by experiment methods such as contact angle measurement. oxidation induced time. SEM/EDX, FTRI-ATR, tracking test for the different insulator samples. With the increased UV exposure time, samples are shown to exhibit degradation comparable to those of new ones

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2845-2849
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• 2008

Long Term Asset Management(LTAM) means a plan developed by using LCM(Life Cycle Management) process for optimum life cycle management of significant plant assets at each plant across the fleet. As a part of development of LTAM Strategies on nuclear turbines, a method so as to determine the future failure rates for low pressure turbine facilities at a nuclear plant was studied and developed by using both plant specific and industry-wide performance data. INPO's EPIX data were analyzed and some failure rate evaluation values considering preventive maintenance practices were calculated by using EPRI's PM Basis software. As the result, failure rate functions applicable to a priori and a posteriori replacement of low pressure turbines at a nuclear plant were developed and utilized in an assessment of economics of LCM alternatives on the nuclear turbine facilities in the respects of 40-year and 60-year operation bases.

• International Journal of Highway Engineering
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• v.18 no.1
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• pp.91-97
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• 2016

PURPOSES : The objective of this paper is to develop a pavement performance model based on the Bayesian algorithm, and compare the measured and predicted performance data. METHODS : In this paper, several pavement types such as SMA (stone mastic asphalt), PSMA (polymer-modified stone mastic asphalt), PMA (polymer-modified asphalt), SBS (styrene-butadiene-styrene) modified asphalt, and DGA (dense-graded asphalt) are modeled in terms of the performance evaluation of pavement structures, using the Bayesian algorithm. RESULTS : From case studies related to the performance model development, the statistical parameters of the mean value and standard deviation can be obtained through the Bayesian algorithm, using the initial performance data of two different pavement cases. Furthermore, an accurate performance model can be developed, based on the comparison between the measured and predicted performance data. CONCLUSIONS : Based on the results of the case studies, it is concluded that the determined coefficients of the nonlinear performance models can be used to accurately predict the long-term performance behaviors of DGA and modified asphalt concrete pavements. In addition, the developed models were evaluated through comparison studies between the initial measurement and prediction data, as well as between the final measurement and prediction data. In the model development, the initial measured data were used.

• Clinical and Experimental Pediatrics
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• v.51 no.9
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• pp.922-934
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• 2008

Developmental language disorder is the most common developmental disability in childhood, occurring in 5-8% of preschool children. Children learn language in early childhood, and later they use language to learn. Children with language disorders are at increased risk for difficulties with reading and written language when they enter school. These problems often persist through adolescence or adulthood. Early intervention may prevent the more serious consequences of later academic problems, including learning disabilities. A child's performance in specific speech and language areas, such as phonological ability, vocabulary comprehension, and grammatical usage, is measured objectively using the most recently standardized, norm-referenced tests for a particular age group. Observation and qualitative analysis of a child's performance supplement objective test results are essential for making a diagnosis and devising a treatment plan. Emphasis on the team approach system in the evaluation of children with speech and language impairments has been increasing. Evidence-based therapeutic interventions with short-term, long-term, and functional outcome goals should be applied, because there are many examples of controversial practices that have not been validated in large, controlled trials. Following treatment intervention, periodic follow-up monitoring by a doctor is also important. In addition, a systematized national health policy for children with speech and language disorders should be provided.

• International Journal of Highway Engineering
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• v.15 no.4
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• pp.107-116
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• 2013

PURPOSES: The liquid-type chemical warm-mix asphalt (WMA) additive has been developed. This study evaluates the basic properties of the additive and the mechanical properties of WMA asphalt and mixture manufactured by using the newly developed chemical additive. METHODS: First, the newly developed WMA additive was applied to the original asphalt by various composition of additive components and dosage ratio of additive. These WMA asphalt binders were evaluated in terms of penetration, softening point, rotational viscosity, and PG grade. Based on the binder test results, one best candidate was chosen to apply to the mixture and then the mechanical properties of WMA mixture were evaluated for moisture susceptibility, dynamic modulus, and rutting and fatigue resistance. RESULTS : According to the binder test, WMA asphalt binders showed the similar properties to the original asphalt binder except the penetraion index of WMA additive was a little higher than original binder. From the Superpave mix design, the optimum asphalt content and volumetric properties of WMA mixture were almost the same with those of hot mix asphalt (HMA) mixture even though the production and compaction temperatures were $30^{\circ}C$ lower for the WMA mixture. From the first set of performance evaluation, it was found that the WMA mixture would have some problem in moisture susceptibility. The additive was modified to improve the resistance to moisture and the second set of performance evaluation showed that the WMA mixture with modified chemical additive would have the similar performance to HMA mixture. CONCLUSIONS : Based on the various laboratory tests, it was concluded that the newly developed chemical WMA additve could be successfully used to produce the WMA mixture with the comparable performance to the HMA mixture. These laboratory evaluations should be confirmed by applying this additive to the field and monitoring the long-term performance of the pavement, which are scheduled in the near future.

• Korean Management Science Review
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• v.21 no.2
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• pp.111-122
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• 2004

Measuring performance of corporate information system has become one of the core issues in that development of the information system requires substantial amount of investments and the system works as a crucial leverage to enhance competitive edge. Most of the previous researches for performance of the information system have narrow and limited focus on such as the effect of user satisfaction and productivity. This paper suggests a model to measures the comprehensive performance which is classified as user scope (user involvement and satisfaction), operational scope (task productivity, task innovation, customer satisfaction, management control) and efficiency scope (financial performance), and to represent the relationship among the scopes by the path analysis model. Followings are conclusions from statistical hypothesis test of the model: (i) user involvement through user satisfaction has positive effect on all the performances in the operational scope, (ii) task innovation and customer satisfaction in the operational scope has statistically significant impact on financial performance but task productivity and management control do not. This conclusion indicates that task productivity and management control has the long term effect in nature, and evaluation of the information system has managerial implication when it Is measured in comprehensive performance which includes internal operational performances as well as financial performance.

• 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.

• IEIE Transactions on Smart Processing and Computing
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• v.6 no.3
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• pp.193-199
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• 2017

Instead of using only spatial features from a single frame for person re-identification, a combination of spatial and temporal factors boosts the performance of the system. A recurrent neural network (RNN) shows its effectiveness in generating highly discriminative sequence-level human representations. In this work, we implement RNN, three Long Short Term Memory (LSTM) network variants, and Gated Recurrent Unit (GRU) on Caffe deep learning framework, and we then conduct experiments to compare performance in terms of size and accuracy for person re-identification. We propose using GRU for the optimized choice as the experimental results show that the GRU achieves the highest accuracy despite having fewer parameters than the others.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.601-606
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• 2002

This study explored physical properties of a hardened cement and a concrete specimen using a high performance cement type solidification consisting of a weathered granite soil and a yellow soil mainly. Also the development of high performance cement type solidification was purposed for an intensity improvement and a long-term durability. As the experimental results, a mortar used by the weathered granite soil shows positive result, however using the yellow soil as a mortar Shows less positive result at the compressive strength. Also the dynamic modulus of elasticity measurement result, the concrete specimens used by the weathered granite and the yellow soil reached above 90%, so it seems to have the durability of freezing and thawing.