• Journal of the korean academy of Pediatric Dentistry
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• v.42 no.1
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• pp.53-61
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• 2015

This study was conducted for the purpose of evaluating the stainless steel crowns on extracted primary molars and thus identifying frequent errors and defects. Visual assessment and micro-computed tomography (micro-CT) image analysis were performed on 97 primary molars for evaluation of the state of marginal adaptation, cement loss, secondary caries, ledge formation, attritive perforation and marginal polishing defect. The results were as follows: In the examination of object teeth by evaluation criteria, cement loss was found most frequently (98%), followed by secondary caries (42.3%), marginal polishing defect (41.2%), ledge formation (29.9%) and attritive perforation (17.5%), in this order. The cement loss at the margins showed a significant relationship with marginal gap and secondary caries: the larger the marginal gap is, the more frequent is the cement loss (p < 0.05). The average marginal gap was $0.31{\pm}0.26mm$ and showed the highest value in the maxillary 2nd primary molars. The location of the crown margin above the cementoenamel junction was found most frequently and it was found that the higher the crown margin is located, the less the marginal gap becomes (p < 0.05). In conclusion, it is thought very desirable to pay closer attention to crown margins and shapes for stainless steel crown restoration in order to minimize the marginal gaps and consequent cement loss.

• The Journal of Korean Academy of Sensory Integration
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• v.8 no.1
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• pp.41-49
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• 2010

Objective : Multisensory integration (MSI) is the essential process to use diverse sensory information for cognitive task or execution of motor action. Especially, visual and somatosensory integration is critical for motor behavior and coordination. This study was designed to explain spatial and temporal characteristics of visual and somatosensory integration by neurophysiological research method that identifies the time course and brain location of the SI process. Methods : Electroencephalography (EEG) and event-related potential (ERP) is used in this study in order to observe neural activities when integrating visual and tactile input. We calculate the linear summation (SUM) of visual-related potentials (VEPs) and somatosensory-related potentials (SEPs), and compared the SUM with simultaneously presented visual-tactile ERPs(SIM) Results : There were significant differences between the SIM and SUM in later time epochs (about 200-300ms) at contralateral somatosensory areas (C4) and occipital cortices (O1&O2). The amplitude of the SIM was mathematically larger than the summed signals, implying that the integration made some extra neural activities. Conclusion : This study provides some empirical neural evidence of that multisensory integration is more powerful than just combing two unisensory inputs in the brain and ERP data reveals neural signature relating to multisensory integrative process. Since this study is preliminary pilot study, larger population and criteria are needed for level of the significance. Further study is recommended to consider issues including effect of internally-driven attention and laterality of interaction to make the evidence by this study solid.

• Korean Journal of Construction Engineering and Management
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• v.17 no.3
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• pp.108-115
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• 2016

The price determinant for land investment depends on the internal information process and subjective decision making by management in general. Accordingly, the systematic frame to determine the feasibility of investment price to the public residential land for multi-housing development by private sector has not been proposed. The purpose of this study is to explore the frame to determine the investment price for public residential land from the perspectives of land attribute and apartment market factor. Multiple regression has been implemented to confirm the eligibility of proposed model. Research findings indicate that the land area, floor area ratio, coverage ratio, location have been identified as the total land cost determinant, and for the determinants for floor area land cost, the ratio of apartment, sale price, rent price, etc, have been identified. This research intends to provide the basis for land providers to predict the land value as a raw material in market and present the indicators for land buyers to review the price adequacy for the investment.

• Journal of Korean Society of Forest Science
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• v.103 no.3
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• pp.483-489
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• 2014

This study aimed at a scientific examination of the relationship between NVOCs concentration and the physical environment of red pine forest in spring season. Atmospheric NVOC samples in red pine forest was collected through five trials conducted from March to May 2013, using Tanax-Ta-charged disposable tubes and mini-pumps. At each trial, measurements were taken at three different points in daytime (sunrise, southing and sunset). For maximum accuracy, two tubes were used for each measurement at the same location, and the mean value was used for analysis. Compound analysis on the NVOC samples was done using the HS-SPME method and GC-MS. Analysis of the relationship between NVOC and the physical forest environment found higher concentrations of most substances, including ${\alpha}$-pinene and ${\beta}$-pinene, with higher temperature, dew point, and lower concentrations with higher wind velocity. The findings of this study offer scientific evidence which can inform the creation of 'healing forests' and 'recreational forests' as well as forest environment in general, helping to promote public health and recreational activities.

• Archives of design research
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• v.17 no.2
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• pp.5-14
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• 2004

Introducing human capacities of control and sensation which have been overlooked into Human-Computer Interaction(HCI), Ubiquitous computing, Augmented Reality and others have been researched recently. New vision of HCI has embodied in Tangible User Interface(TUI). TUI allows users to grasp and manipulate bits with everyday physical object and architectural surface and also TUI enables user to be aware of background object at the periphery of human perception using ambient display media such of light, sound, airflow and water movement. Tangibles, physical object which constitutes TUI system, is the physical object embodied digital bit. Tangibles is not only input device but also the configuration of computing. To get feedback of computing result, user controls the system with Tangibles as action and the system represents reaction in response to User's action. User appreciates digital representation (sound, graphic information) and physical representation (form, size, location, direction etc.) for reaction. TUI's characters require the consideration about both user's action and system's reaction. Therefore we have to need the method to be concerned about physical object and interaction which can be combined with action, reaction and feedback.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.6_1
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• pp.483-491
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• 2013

By a development of car navigation systems and mobile or positioning technology, it increases interest in location based services, especially pedestrian navigation systems. Updating of digital maps is important because digital maps are mass data and required to short updating cycle. In this paper, we proposed change detection for different network data-sets based on areal feature matching. Prior to change detection, we defined type of updating between different network data-sets. Next, we transformed road lines into areal features(block) that are surrounded by them and calculated a shape similarity between blocks in different data-sets. Blocks that a shape similarity is more than 0.6 are selected candidate block pairs. Secondly, we detected changed-block pairs by bipartite graph clustering or properties of a concave polygon according to types of updating, and calculated Fr$\acute{e}$chet distance between segments within the block or forming it. At this time, road segments of KAIS map that Fr$\acute{e}$chet distance is more than 50 are extracted as updating road features. As a result of accuracy evaluation, a value of detection rate appears high at 0.965. We could thus identify that a proposed method is able to apply to change detection between different network data-sets.

• Korean Journal of Biological Psychiatry
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• v.6 no.1
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• pp.21-29
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• 1999

Traumatic Brain Injury(TBI) of any severity can result in broad and persisting biopsychosocial sequelae. Depression after TBI occur at a greater frequency than in the general population, with estimates approaching 25% to 50% for major depression, and 155 to 30% for dysthmia. Acute onset depressions are related to lesion location and may have their etiology in biological response of the injured brain, whereas delayed onset depressions may be mediated by psychosocial factors, suggesting psychological reactions as a possible mechanism. Anxious depressions are associated with right hemisphere lesions, whereas major depressions alone are associated with left dorsolateral frontal and left basal ganglia lesions. However, there is insufficient information to postulate a specific neuroanatomic model for TBI-related depression.

• International Journal of Highway Engineering
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• v.13 no.2
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• pp.139-145
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• 2011

The practice of asphalt pavement recycling has grown rapidly over the decade, one of which is the cold in-place recycling with the foamed asphalt (CIR-foam) or the emulsified asphalt (CIR-emulsion). Particularly, in Iowa, the CIR has been widely used in rehabilitating the rural highways because it significantly increases the service life of the existing pavement. The CIR layer is typically overlaid by the hot mix asphalt (HMA) to protect it from water ingress and traffic load and obtain the required pavement structure and texture. Most public agencies have different curing requirements based on the number of curing days or the maximum moisture contents for the CIR before placing the overlay. The main objective of this study is to develop a moisture loss index that the public agency can use to monitor the moisture content of CIR layers in preparation for a timely placement of the wearing surface. First, the moisture contents were measured in the field using a portable time domain reflectometry (TDR) device. Second, the weather information in terms of rain fall, air temperature, humidity and wind speed was collected from the same location. Finally, a moisture loss index was developed as a function of initial moisture content, air temperature, humidity and wind speed. The developed moisture loss index based on the field measurements would help the public agency to determine an optimum timing of an overlay placement without continually measuring moisture conditions in the field.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.1
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• pp.121-129
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• 2008

Major factors affecting water quality in rivers are transportation, input of pollutant loads and kinetic transformation of pollutants. Government level decision makings on water quality management are based on steady state water quality modeling. However, it is more than often that such a steady state assumption is far from real situations in rivers. Therefore, it is unavoidable to have modeling errors in water quality modeling especially for steady state modeling for longer period of time. Authors attempted to identify sources of errors in results of steady state models and thus tried to find out ways to minimize those errors. Three water quality models, QUAL2E (Brown et al., 1983), QUAL2K (Chapra et al., 2006) and CAP (Seo and Lee, 2000) were applied to the lower stream of the Geum River. $BOD_5$ and COD tend to underestimate observed data while TN and TP showed relatively smaller errors. QUAL2E model provided best calibration results for BOD5 and TP and QUAL2K model showed best calibration results for TN. Since these errors are only relative values, it was difficult to conclude which model is better performing in certain situations. The most probable reasons for errors in water quality modeling are; 1) inappropriate consideration on flow characteristics, 2) lack of information on incoming pollutant load and 3) inappropriate location of sampling for water quality analysis.

• Geophysics and Geophysical Exploration
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• v.14 no.1
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• pp.50-57
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• 2011

For effective and accurate prediction of overpressure in the Efomeh field, located in the Niger delta basin of Nigeria, integrated seismic and borehole analyses were undertaken. Normal and abnormal pore pressure zones were delineated based on the principle of normal and deviation from normal velocity trends. The transition between the two trends signifies the top of overpressure. The overpressure tops were picked at regular intervals from seismic data using interval velocities obtained by applying Dix's approximation. The accuracy of the predicted overpressure zone was confirmed from the sonic velocity data of the Efomeh 01 well. The variation to the depth of overpressure between the predicted and observed values was less than 10mat the Efomeh 01 well location, with confidence of over 99 per cent. The depth map generated shows that the depth distribution to the top of the overpressure zone of the Efomeh field falls within the sub-sea depth range of 2655${\pm}$2m (2550 ms) to 3720${\pm}$2m (2900 ms). This depth conforms to thick marine shales using the Efomeh 01 composite log. The lower part of the Agbada Formation within the Efomeh field is overpressured and the depth of the top of the overpressure does not follow any time-stratigraphic boundary across the field. Prediction of the top of the overpressure zone within the Efomeh field for potential wells that will total depth beyond 2440m sub-sea is very important for safer drilling practice as well as the prevention of lost circulation.