• Steel and Composite Structures
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• v.28 no.4
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• pp.439-447
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• 2018

The structural behaviors of cylindrical barns as a specific engineering structure have been considered as a complicated computing process. The structure design against the earthquake load, to protect by using the code, is an urgency avoiding unexpected damages. The situation has been subjected to the applied design method if there would be no failure across the construction procedures. The purpose of the current study is to clarify the behaviors of cylindrical reinforced concrete barns through the analytic methods across the mass and Lagrangian approaches through the whole outcomes comparison indicating that the isoparametric element obtained from the Lagrangian approach has been successfully applied in the barns earthquake analysis when the slosh effects have been discarded. The form of stress distributions is equal with $s_z$ closed distributions to one another.

• Journal of Korean Society of Transportation
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• v.17 no.3
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• pp.117-130
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• 1999

Earthquakes damage roadway bridges and structures, resulting in significant impacts on transportation system Performance and regional economy. Seismic risk analysis (SRA) procedures establish retrofit priorities for vulnerable highway bridges. SRA procedures use average daily traffic volumes to determine the relative importance of a bridge. This research develops a cost-effective transportation network analysis (TAN) procedure for evaluating numerous traffic flow analyses in terms of the additional system cost due to failure. An important feature of the TNA Procedure is the use of an associative memory (AM) approach in the artificial intelligence held. A simple seven-zone network is developed and used to evaluate the TNA procedure. A subset of link failure system states is randomly selected to simulate synthetic post-earthquake network flows. The performance of different AM model is evaluated. Results from numerous link-failure scenarios demonstrate the applicability of the AM models to traffic flow estimation.

• Journal of the Earthquake Engineering Society of Korea
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• v.2 no.2
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• pp.35-44
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• 1998

Because of the continual occurrence of minor and moderate earthquakes in Korean peninsula, it is generally considered that Korean is not located in a safe region against probable earthquake any more, even though being recognized as a safe country in earthquake. It is in particular noted that nowadays there has been much concern about unexpected tragedy due to probable earthquake since the disaster of 1995 kobe earthquake. Thus, the objective of this research is to develop appropriate design spectrum which could be practicably used in seismic design of important structures taking into consideration of local physical characteristics. Particularly, we have to keep in mind the lessons from 1985 Mexico earthquake which had disregarded deep research on local ground conditions, being a possible magnification phenomena of ground motions in weak soil layer. Various spectra has been described based on the analysis of historical earthquakes, and generate the artificial ground acceleration. Also, rational numbers of artificial ground acceleration is investigated by the seismic analysis for skew slab bridges.

• Journal of the Earthquake Engineering Society of Korea
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• v.22 no.4
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• pp.253-259
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• 2018

Structure behaviors resulting from an earthquake are experimentally simulated mainly through a shaking table test. As for large-scale structures, however, size effects over a miniature may make it difficult to assess actual behaviors properly. To address this problem, research on the hybrid simulation is being conducted actively. This method is to implement numerical analysis on framework members that affect the general behavior of the structure dominantly through an actual scale experiment and on the rest parts by applying the substructuring technique. However, existing studies on hybrid simulation focus mainly on Slow experimental methods, which are disadvantageous in that it is unable to assess behaviors close to the actual level if material properties change depending on the speed or the influence of inertial force is significant. The present study aims to establish a Real-time hybrid simulation system capable of excitation based on the actual time history and to verify its performance and applicability. The hybrid simulation system built up in this study utilizes the ATS Compensator system, CR integrator, etc. in order to make the target displacement the same with the measured displacement on the basis of MATLAB/Simulink. The target structure was a 2-span bridge and an RC pier to support it was produced as an experimental model in order for the shaking table test and Slow and Real-time hybrid simulations. Behaviors that result from the earthquake of El Centro were examined, and the results were analyzed comparatively. In comparison with the results of the shaking table test, the Real-time hybrid simulation produced more similar maximum displacement and vibration behaviors than the Slow hybrid simulation. Hence, it is thought that the Real-time hybrid simulation proposed in this study can be utilized usefully in seismic capacity assessment of structural systems such as RC pier that are highly non-linear and time-dependent.

• Computational Structural Engineering
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• v.10 no.3
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• pp.157-165
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• 1997

This research aims to develop an algorithm of optimal transducer placement for health monitoring of large structural system. The structural vibration response-based health monitoring is considered one of the best for the system which requires a long-term, continuous monitoring. In its experimental modal testing, however, it is difficult to decide on the measurement locations and their number, especially for complex structures, which have a major influence on the quality of the results. In order to minimize the number of sensing operations and optimize the transducer location while maximizing the accuracy of results, this paper discusses about an optimum transducer placement criterion suitable for the identification of structural damage for continuous health monitoring. As a criterion algorithm, it proposes the Kinetic Energy Optimization Technique (EOT), and then addresses the numerical issues which are subsequently applicable to actual experiment where a bridge model is used. By using the experimental data, it compares the EOT with the EIM(Effective Indefence Method) which is generally used to optimize the transducer placement for the damage identification and control purposes. The comparison conclusively shows that the EOT algorithm proposed in this paper is preferable when a structure is to be instrumented with fewer sensors for monitoring purpose.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.1
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• pp.120-125
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• 2004

Cornelia de Lange syndrome is a disorder of unknown etiology resulting in an syndrome characterized by specific dysmorphic features. Therefore this syndrome is diagnosed only by clinical features and other examinations for diagnostic aim are not effective. There are general growth retardation, mental retardation, hypertrichosis, confluent eye brows, low hair line, broad nasal bridge, anteverted nose tip, malformed limbs, webbing of toes, heart defect, gastroesophageal reflux disease, ear and ocular problems. Features associated oral structures are micrognathia, delayed eruption of teeth, cleft lip, cleft plate, thin upper lip and downturned angles of mouth. These are cases about two children who visited Department of Pediatric Dentistry of Chonbuk National University because of dental caries with Cornelia do Lange syndrome.

• Journal of KIBIM
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• v.5 no.3
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• pp.33-40
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• 2015

Over a few decades, off-site construction (OSC) has been widely used for building and bridge constructions. OSC is a construction method that build structures at a different location than the location of use, and normally it occurs in a manufacturing plant. There are many studies on the perceived benefits of OSC, yet relatively few studies which quantitatively assess the benefits and factors affecting the decision of the use of OSC have been investigated. This study investigates the influencing factors of the use of OSC system and its revitalization solutions in the construction industry. As the research method, interview and questionnaire survey are conducted by visiting industry experts of OSC and sending a questionnaire to the OSC stakeholders including engineers, manufacturers, contractors and clients in the United Kingdom (UK). The construction industry of the UK is targeted for the study since it has a number of commons with the Korean construction industry in terms of the structure of the construction industry and current low take-up of the OSC. The survey provides the results that the reluctance of clients to use OSC is the key factor of the slow use of OSC despite of the perceived benefits of OSC. In addition, in order to revitalize OSC in the construction market, three revival recommendations are suggested based on the survey results.

• Journal of Dental Rehabilitation and Applied Science
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• v.21 no.1
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• pp.43-57
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• 2005

Temporomandibular disorders have been defined as a collective term embracing a number of clinical problems that involve the temporomandibular joint, the masticatory nuscles, and associated structures. There have been many different contributing factors of TMDs which were traumatic, occlusal, pathophysiological and psychosocial. Among there factors, the effect of occlusion on TMDs have been a controversy for a long time. The purpose of this study was to investigate the effect of occlusal factors and oral habits on TMDs. In this study, 140 subjects with signs and symptoms of TMDs and diagnosed of TMD in the Orofacial Pain clinic of Yonsei University Dental Hospital though March to July 2004 were selected for the TMDs group and 50 subjects without any signs and symptoms of TMDs as the control group. The subjects were evaluated clinically in TMDs' Occlusal and Prosthodontic Restoration examinations. TMDs' examination was composed of the TMJ pain, sound, locking, temporal or masseter muscle palpation, mandibular movement, oral habits and headache. Occlusal examination was made of overjet, overbite, lost teeth number, nonfunctional interference, midline shift, then pattern of lateral movement and attrition. prosthodontic restoration examination had the existence of restoration, placement, then number of crown or bridge and Satisfiable index which estimated the quality of occlusal state of prosthodontic restorations. Following results were obtained : 1. The prevalence of TMDs was higher in their 20s & 30s, female of the TMD patients group. 2. The clenching frequency in the TMDs group(40.71%) was higher than those in the control group(18.00%), and there was a significant statistical difference(p<0.05). 3. The frequency of Nonfunctional interference in the TMDs group(10.00%) was higher than those in then Control group(2.00%), and there was a significant statistical difference(p<0.05). The result of this study indicated TMDs prevalence was higher in their 20s, 30s, female group of TMDs patients similar to the previous studies. Clenching and nonfunctional interference were estimated as the contributing factors of TMDs.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.5
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• pp.173-181
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• 1993

Under natural conditions, rivers do not in general take straight courses but instead take winding courses. This is known as meandering of rivers. Meandering of rivers are so complicated because of the mutual interactions between flow and movable boundaries. In quantitative information, it is important to predict the future location of a river channel(channel migration) because in selecting a bridge site or a location of a road. It may be valuable to know the future impact of a nearby river on those structures. When the prediction model of the migration of channel is used in domestic rivers with high coefficient of river regime, it is rational to use the periodical dominant discharge (PDD), which is named firstly by the author, instead of the average discharge. According to the analysis of the erosion coefficient, the mean deviation on the channel migration, and the bed scour factor, it can bring shedding light on the fact that the discharge is one of the dominant components in channel migration. In project area, the discharge that can shift the channel is slightly greater than 6,000CMS. The prediction model of the migration of channel estimated the erosion coefficient, $E_0$ by the data from the South Han River. This estimated value from the South Han River was also used to predict the migration of the South Han River in year 2000.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.6
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• pp.1395-1404
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• 1994

Transverse bed slope in bend is a subject of scientific investigation since it provides the necessary information for channel design and protection of hydraulic structures (bank, bridge, etc), and study of river morphology. In this paper, selected models were examined and compared for the value of prediction of the transverse bed slope in curved alluvial channels(project area), by using field data, and fitting model was proposed. All models that related the local transverse bed slope to mean flow characteristics were alike in the sense that they predicted the local transverse bed slope to be proportional to the ratio between depth and radius of curvature. The difference among the models was related with the factor of proportionality, K. Also, measured transverse bed slope was correlated to mean velocity, maximum depth, and density Froude number in channel bend. In this paper selected models were compared for the prediction of the transverse bed slope using Odgaard's experiment (obtained in Sacramento River bend), so Odgaard89 model was closely related with real transverse bed slope.