• Journal of Korean Society of Steel Construction
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• v.8 no.4 s.29
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• pp.19-29
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• 1996

In this paper, it is presumed that the stress time history was generated by simulation method and investigated compatibility in regard to the reappearance of stress time history. In this procedure, the identified frequency distribution of stress range of the steel railroad bridge varies with the rational values of cut off point and bar width. Thus, we show variable aspect of the equivalent stress range results from change of cut off point and bar width. In addition, we analyze the variable of RMC and RMS model due to the cut off point and bar width of the measured stress history which influencs the prediction of fatigue life in the steel railroad bridge. The simulated stress time history is carried out by the superposition method incorporating the vertical load with rotation moment obtained from the Hermition interpolation function, and compared with developing stress results from measured maxi mum stress. Through this study, we can estimate the remaining fatigue life from a safety point of view and comparative accuracy.

• Earthquakes and Structures
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• v.6 no.4
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• pp.375-392
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• 2014

Time history analyses have been preferred commonly in earthquake engineering area to determine earthquake performances of structures in recent years. Advances in computer technology and structural analysis have led to common usage of time history analyses. Eurocode 8 allows the use of real earthquake records as an input for linear and nonlinear time history analyses of structures. However, real earthquake records with the desired characteristics sometimes may not be found, for example depending on soil classes, in this case artificial and synthetic earthquake records can be used for seismic analyses rather than real records. Selected earthquake records should be scaled to a code design spectrum to reduce record to record variability in structural responses of considered structures. So, scaling of earthquake records is one of the most important procedures of time history analyses. In this paper, four real earthquake records are scaled to Eurocode 8 design spectrums by using SESCAP (Selection and Scaling Program) based on time domain scaling method and developed by using MATLAB, GUI software, and then scaled and real earthquake records are used for linear time history analyses of a six-storied building. This building is modeled as spatial by SAP2000 software. The objectives of this study are to put basic procedures and criteria of selecting and scaling earthquake records in a nutshell, and to compare the effects of scaled earthquake records on structural response with the effects of real earthquake records on structural response in terms of record to record variability of structural response. Seismic analysis results of building show that record to record variability of structural response caused by scaled earthquake records are fewer than ones caused by real earthquake records.

• Journal of the Korea Institute of Military Science and Technology
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• v.8 no.3 s.22
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• pp.73-82
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• 2005

This paper describes shock waveform synthesis methods for a shock response spectnlm over a short time interval with which intereference between parts within a test item is increased to perform a sufficient shock test for damage or malfunction which may be caused by the interference between parts, and a digital filter for obtaining a shock response history required for the shock waveform synthesis and a digital inverse filter for restoration by inversely using the digital filter. The time at which the maximax value occurs in the response history is detected in order to establish a delay time which is one of the parameters in the wavelet, on the condition that the natural frequency of SDOF system with a Q (quality factor) of 10 equals to the wavelet frequency of the zero delay wavelet input. A shock response spectrum over a short time interval and an abrupt change in the acceleration for an instant are illustrated as features of the synthesized waveform.

• Journal of KSNVE
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• v.10 no.4
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• pp.686-691
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• 2000

In this paper a computer aided analysis method is proposed for durability assessment in the early design stages using dynamic analysis, stress analysis and fatigue life prediction method. From dynamic analysis of a vehicle suspension system, dynamic load time histories of a suspension component are calculated. From the dynamic load time histories and the stress of the suspension component, a dynamic stress time history at the critical location is produced using the superposition principle. Using linear damage law and cycle counting method, fatigue life cycle is calculated. The predicted fatigue life cycle is verified by experimental durability tests.

• Tunnel and Underground Space
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• v.9 no.1
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• pp.36-47
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• 1999

For cautious controlled blasting, it is necessary to understand characteristics of the blasting vibration. In this study, a series of tests were carried out to investigate the several characteristics of blasting vibration waveform by vibration time history analysis. Separation between impulse vibration and free vibration from blasting vibration, duration time, effects of overlap of free vibration upon the level of vibration and changes of waveform according to increase of charge weight per delay etc. were studied with waveform analysis.

• Journal of dental hygiene science
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• v.20 no.4
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• pp.261-268
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• 2020

Background: A comprehensive history taking at the first visit could be an important start of treatment. This study investigated the current status of the initial history taking for dental patients in S area, and the implementation and importance of the initial history taking process. Based on this, we intend to provide basic data for the development of organized and standardized questionnaires in dental clinics. Methods: In April 2019, 303 dental clinics in S area were targeted and special dental clinics (orthodontics, children, and disabled) were excluded. The questionnaire consisted of 29 items, including general characteristics, systemic disease history, dental history, oral health behaviors, and the data were obtained through self-administered questionnaire. Results: Initial history taking was mostly implemented using oral and questionnaire at the time of the first visit. Systemic disease history, dental history, and oral health behaviors differed in the work experience of the dental clinic staff. As a result of analyzing the importance according to implementation, there were significant differences in all questions except drug-related items. The importance of the questionnaire was highly recognized, but the reason it was not actually implemented was because of existing the questionnaire in the clinic and lack of time. Conclusion: Considering that the initial history taking implementation rate showed low, it is necessary to develop standardize a practical questionnaire and interview skills for dental clinics in the future. In addition, training programs should be provided to dental staff that can recognize the importance of initial history taking questionnaires and contribute to active implementation.

• The Journal of Pediatrics of Korean Medicine
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• v.18 no.2
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• pp.77-91
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• 2004

Objectives : In evaluating a child with enuresis, an organized approach to the history leads to a working diagnosis and an appropriate treatment plan. but, there's no study about history taking in enuretic children. This article was undertaken to evaluate the enuretic child exactly and to study nocturnal enuresis systematically. Methods : It was conducted a computerized literature search in following database: Medline (via Pubmed), NDSL, EBSCO. Korean articles via oriental pediatric association homepage, KISS. Key words to search were 'nocturnal enuresis', 'bedwetting', 'enuresis', 'incontinence', 'management', 'evaluation', 'assessment', 'questionnaire', 'guideline', 'voiding dysfunction'. Results : Questions are grouped in eight categories: primary history(sex, age, height, weight), family history, enuresis history(primary/secondary, frequency, time of enuresis, nocturia), voiding history(average number, frequency, pattern, volume, posture, daytime enuresis), medical history, constipation/encopresis, sleep(OSA). Conclusion : A careful, complete history taking will help to plan treatment properly and to study.

• Journal for History of Mathematics
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• v.16 no.3
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• pp.57-68
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• 2003

Infinity is very important concept in mathematics. In history of mathematics, potential infinity concept conflicts with actual infinity concept for a long time. It is reason that actual infinity concept causes difficulty in our perceptions. This phenomenon is called epistemological obstacle by Brousseau. So, in this paper, we examine the infinity in terms of mathematical didactics. First, we examine the history of development of infinity and reveal the similarity between the history of debate about infinity and episternological obstacle of students. Next, we investigate obstacle of students about infinity and the contents of curriculum which treat the infinity Finally, we suggest the methods for overcoming obstacle in learning of infinity concept.

• Journal of architectural history
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• v.1 no.1 s.1
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• pp.255-266
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• 1992

The Main concern of this thesis is on the possibility to apply Hermeneutics to architectural history, with a view point that the past architecture can be seen as a text, this study analyse the relationship between the past building and interpreter, the epistenological tool for interpretation and historian. After reviewing the characteristics of architectural history with regard to text theory, this study can lead to the conclusion that the interpretation of past architecture can be defired as dynamic dialogue which depend upon the time.

• Journal of East-Asian Urban History
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• v.1
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• pp.81-96
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• 2019

This paper attempts to rethink the ancient Emperor's Capital transition process from the viewpoint of territorial history. Emperor Tenmu, who planned first capital as Fujiwara-kyo in Asuka region, had a grand plan to put multiple cities in Japan. At that time the important cities were situated along east-west axis. However, since relocation of the capital from Fujiwara-kyo to Heijyo-kyo, the axis had turned towards north-south direction. The last ancient capital Heian-kyo was clearly organized utilizing north-south water systems in territorial sense.