• Transactions of the Korean Society of Automotive Engineers
• /
• v.10 no.1
• /
• pp.153-161
• /
• 2002

This paper develops a finite element model for crashworthiness analysis ova small-sized bus. The full vehicle finite element model is composed of 31,982 shell elements,599 beam elements,42 bar elements, and 34,204 nodes. The model uses four material models (such as elastic, elastic-plastic(steel), rigid. and elastic-plastic (rubber) material model) of PAM-CRASH. The model uses four contact types to define sliding interfaces in ten areas. A frontal crash test using an actual vehicle with 30mph velocity to a rigid barrier is carried out. Vehicle pulses at lower part of left and right b-pillar are measured, and deformed shapes of frame and driver seat's lower left area are photographed. A frontal crash simulation using the developed full vehicle finite element model is performed with PAM-CRASH installed in super computer SP2. The simulation is performed with the same conditions as the test. The measured vehicle pulses and photographed deformed shapes from the test are compared to ones from the simulation to validate the reliability of the developed model.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.14 no.1_2
• /
• pp.54-64
• /
• 1992

The balance of facial sop tissue is important factor for the treatment of maxillofacial deformity patients. There are many cephalometric analysis of facial bone but a few soft tissue analysis of face for the orthognathic surgery, especially in the oriental people. This study aimed at examining the mean value of the soft tissue measurement of 120 Korean adult women with the linear and angular measurement and comparing with Caucasian. The results ere as follows. 1. In the frontal linear measurement, Korean women have larger interocular distant and width of nose, but the width of mouth appeared less than Caucasian. 2. In the frontal angular measurement, Korean women have larger inclination of the eye than Caucasian. 3. In the lateral linear measurement, Korean women have more prominent upper and lower lip position than Caucasian and have longer upper facial height comparing with lower facial height than Caucasian. 4. In the lateral angular measurement, Korean women have more convex facial profile and less nasolabial and geniolabial angle. 5. In the lateral facial ratio, Korean women have larger proportion in the lower department below the stomion.

• Journal of Korean Neurosurgical Society
• /
• v.64 no.5
• /
• pp.763-775
• /
• 2021

Objective : Hemorrhagic transformation (HT) can be occurred after acute cerebral infarction. HT can worse symptoms in severe cases and adversely affect long-term prognosis. As bone and vascular smooth muscle are composed of type 1 collagen, we aimed to identify a potential relationship between bone mineral density (BMD) and HT after acute cardioembolic stroke. Methods : As an indicator of BMD, we used mean frontal skull Hounsfield unit (HU) values on brain computed tomography (CT). Multivariative hazard ratios were calculated using Cox regression analysis to identify whether the osteoporotic condition was an independent predictor of HT after acute cardioembolic stroke. Results : This 11-year analysis enrolled 506 patients who diagnosed as acute cardioembolic infarction. The first tertile of skull HU value was an independent predictor of HT development compared to the third tertile (hazard ratio, 2.12; 95% confidence interval, 1.13-3.98; p=0.020). We observed no interactions between age and skull HU with respect to HT statistically. Conclusion : The results of this study revealed an association between osteoporotic conditions and HT development after acute cardioembolic stroke. A convenient method to measure the cancellous bone HU value of the frontal skull using brain CT images may be useful for predicting HT in patients with acute cerebral infarction.

• Journal of Pharmacopuncture
• /
• v.26 no.3
• /
• pp.276-284
• /
• 2023

Objectives: Previous studies have shown that anger can lead to frontal lobe α (8-13 Hz) band asymmetry (FAA) in electroencephalogram (EEG), in accordance with motivational direction. This pilot study aimed to investigate the impact of acupuncture on FAA elicited by anger. Methods: Thirty-four right-handed participants scoring above 75 points on the Novaco Anger Scale were included. Baseline EEG signals were recorded for eight minutes using a 32-channel cap under comfortable conditions. Anger was induced through a nine-minute sequence of Articulated Thoughts in Simulated Situations (ATSS) task. Following that, participants received acupuncture at GB20 and GB21 for 10 minutes. Fast Fourier transform was employed for frequency analysis, and repeated measure ANOVA was conducted for statistical analysis. Results: The results revealed that participants exhibited significantly higher FAA (p = 0.026), particularly in the left hemisphere, after the ATSS task sequence compared to the baseline. During acupuncture treatment, the greater left-sided FAA was significantly reduced (p = 0.027) and reversed. Upon the cessation of acupuncture, FAA returned to a value between the baseline and the anger-evoked stage (p = 0.046). Conclusion: The EEG results of this study revealed that anger stimulation induced an increase in left-sided FAA, which was effectively alleviated by acupuncture. This led to an immediate restoration of FAA asymmetry induced by anger. These findings suggest the potential of acupuncture as a treatment option for reducing FAA associated with anger.

• The korean journal of orthodontics
• /
• v.27 no.2
• /
• pp.245-258
• /
• 1997

Cephalometric radiographs, frontal photographs and profile silhouette phogographs of 68 young adult female who were model or were recommended to have esthetic face were used in this study. 7 Students in department of Art of Kyungpook national university and 15 orthodontists estimated profile slides which were made of 3 Profile silhouettes in parallel with FH plane. Profile silhouettes were made of soft tissue profile line of cephalometric radiograph. Only orthodontists estimated frontal photographs. Students and orthodontists score 9 in excellent case, score 7 in good case, score 5 in average case, score 3 in poor case. Correlation analysis between orthodontists' esthetic concept and Artists' esthetic concept, between frontal view esthetics and profile view esthetics which estimated by orthotontists, between profile view esthetics and profile measurements which consisted of measurements of 38 female who were scored above 5 mean score in profile silhouette by orthodontists were done. And the finding in this study indicated the following 1. Correlation between orthodontists' esthetic concept and Artists' esthetic concept in profile silhouette was significant (r=0.67,P=0.0001). 2. Correlation between frontal view esthetics and profile view esthetics which estimated by orthodontist was significant (r=0.26,P=0.0381). 3. Measurements which had significant correlation between profile measurements and profile view esthetics wer Na-Pog, to N', BNV to Pog', BNV/B' -Pog', Ls-Li-Pog', Li-B'-Pog' Z angle(P<0.05). 4 Mean and standard deviation of profile measurements of 38 female were obtained.

• The korean journal of orthodontics
• /
• v.35 no.3 s.110
• /
• pp.163-173
• /
• 2005

The purpose of this study was to compare the asymmetric degree between maxillofacial hard and soft tissues in individuals with facial asymmetry. Computerized tomographies (CT) of 34 adults (17 male, 17 female) who had facial asymmetry were taken. The CT images were transmitted to personal computers and then reconstructed into three-dimensional (3D) images through the use of computer software. In order to evaluate the degree of facial asymmetry, 6 measurements were constructed as the hard tissue measurements while 6 counterpart measurements were taken as the soft tissue measurements. The means and standard deviations were obtained for each measurement using 3D measure, then t-test was used to investigate the differences between each hard tissue measurement and the corresponding soft tissue measurement All measurements used in the present study showed statistically significant differences between the hard and soft tissues. The degree of soft tissue asymmetry was smaller than that of corresponding hard tissue asymmetry in case of chin deviation, frontal ramal inclination difference, and frontal corpus inclination difference. On the other hand, the degree of soft tissue asymmetry was greater than that of underlying hard tissue asymmetry in the measurement of lip canting and lip cheilion height difference The present study suggests that asymmetric differences of hard and soft tissue is observed nu facial asymmetric subjects and thus soft tissue analysis is needed in addition to hard tissue analysis when making an evaluation of facial asymmetry.

• Journal of Biomedical Engineering Research
• /
• v.39 no.3
• /
• pp.124-133
• /
• 2018

We tried to investigate the changes in cortical activities according to emotional valence states during watching video clips. We examined the neural basis of two emotional states (positive and negative) using spectral power analysis and brain functional connectivity analysis of cortical current density time-series reconstructed from high-density electroencephalograms (EEGs). Fifteen healthy participants viewed a series of thirty-two 2 min emotional video clips. Sixty-four channel EEGs were recorded. Distributed cortical sources were reconstructed using weighted minimum norm estimation. The temporal and spatial characteristics of spectral source powers showing significant differences between positive and negative emotion were examined. Also, correlations between gamma-band activities and affective valence ratings were determined. We observed the changes of cortical current density time-series according to emotional states modulated by video clip. Gamma-band activities showed significant difference between emotional states for thirty seconds at the middle and the latter half of the video clip, mainly in prefrontal area. It was also significantly anti-correlated with the self-ratings of emotional valence. In addition, the gamma-band activities in frontal and temporal areas were strongly phase-synchronized, more strongly for negative emotional states. Cortical activities in frontal and temporal areas showed high spectral power and inter-regional phase synchronization in gamma-band during negative emotional states. It is inferred that the higher amygdala activation induced by negative stimuli resulted in strong emotional effects and caused strong local and global synchronization of neural activities in gamma-band in frontal and temporal areas.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.34 no.1
• /
• pp.26-33
• /
• 2012

Purpose: The golden ratio has been used for a long time to objectify and quantify 'beauty'. Dr. Marqurardt claims that the golden ratio can be applied in the maxillofacial field as well. The purpose of this study was to evaluate the diagnostic significance of using a facial 'phi' mask for analyzing Korean faces with characteristics of Class I, II, and III malocclusion. Methods: We studied twenty five Korean celebrities' frontal facial photos (10 males, 15 females) and 90 malocclusion patients' frontal facial photos (30 patients in each malocclusion classification: Class I, Class II, and Class III). Patients who received orthodontic treatment at Samsung Medical Center were selected for this study. After superimposition of the selected facial photo and facial 'phi' mask using Adobe Photoshop CS3, the ratio of the entire facial area, mid facial area, lower facial area and horizontal and vertical lengths were measured. Results: The facial ratio in photos of Korean faces showed larger vertical and horizontal ratios than the facial 'phi' mask with golden ratio, regardless of skeletal malocclusion (entire face: 115%, lower face: 125% larger than the mask). The results of the frontal photos of Class I, II, and III malocclusion patients using facial 'phi' mask showed that the vertical length and frontal face area was more significantly influenced by the area of the lower face than the midface. This means that the lower face has larger proportions in the facial areas. Conclusion: The ratio of facial 'phi' mask is matched with the ideal facial appearance that the contemporary Korean general public is seeking. Thus, the facial 'phi' mask may be a convenient tool for esthetic analysis of Korean faces. Reducing the area of the lower face is esthetically more desirable for almost all Korean people when planning orthognathic surgery.

• Science of Emotion and Sensibility
• /
• v.6 no.1
• /
• pp.39-45
• /
• 2003

To investigate the changes of cortico-cortical connectivity during odor stimulation of subjects classified by occupations, the mutual information content of EEGs was examined, for general workers, perfume salespersons and professional perfume researchers. Analysis of the averaged-cross mutual information content (A-CMI) from the EEGs revealed that, among the professional perfume researchers,. changes in the A-CMI values during odor stimulation were more apparent in the frontal region of the brain, although for the general workers group and perfume salespersons group such changes were more conspicuous in the overall posterior temporal, parietal and frontal regions. These results indicate that the brains of professional perfume researchers respond to odors mainly in the frontal region, reflecting the function of the orbitofrontal cortex (OFC) due to the occupational requirement of these subjects to discriminate of identify odors. During odor stimulation, the perfume salespersons, although relatively more exposed to odors than the general workers, showed similar changes to the general workers. A-CMI value is in inverse proportion to psychological preferences of the professional perfume researchers and perfume salespersons, but this is not the case with the general workers. This suggests that functional coupling for people who are occupationally exposed to odors may be related to odors nay be related to psychological preference.

• Korean Journal of Radiology
• /
• v.24 no.4
• /
• pp.324-337
• /
• 2023

Objective: The objective of this study was to analyze the different brain oxygen metabolism statuses in preeclampsia using magnetic resonance imaging and investigate the factors that affect cerebral oxygen metabolism in preeclampsia. Materials and Methods: Forty-nine women with preeclampsia (mean age 32.4 years; range, 18-44 years), 22 pregnant healthy controls (PHCs) (mean age 30.7 years; range, 23-40 years), and 40 non-pregnant healthy controls (NPHCs) (mean age 32.5 years; range, 20-42 years) were included in this study. Brain oxygen extraction fraction (OEF) values were computed using quantitative susceptibility mapping (QSM) plus quantitative blood oxygen level-dependent magnitude-based OEF mapping (QSM + quantitative blood oxygen level-dependent imaging or QQ) obtained with a 1.5-T scanner. Voxel-based morphometry (VBM) was used to investigate the differences in OEF values in the brain regions among the groups. Results: Among the three groups, the average OEF values were significantly different in multiple brain areas, including the parahippocampus, multiple gyri of the frontal lobe, calcarine, cuneus, and precuneus (all P-values were less than 0.05, after correcting for multiple comparisons). The average OEF values of the preeclampsia group were higher than those of the PHC and NPHC groups. The bilateral superior frontal gyrus/bilateral medial superior frontal gyrus had the largest size of the aforementioned brain regions, and the OEF values in this area were 24.2 ± 4.6, 21.3 ± 2.4, and 20.6 ± 2.8 in the preeclampsia, PHC, and NPHC groups, respectively. In addition, the OEF values showed no significant differences between NPHC and PHC. Correlation analysis revealed that the OEF values of some brain regions (mainly involving the frontal, occipital, and temporal gyrus) were positively correlated with age, gestational week, body mass index, and mean blood pressure in the preeclampsia group (r = 0.361-0.812). Conclusion: Using whole-brain VBM analysis, we found that patients with preeclampsia had higher OEF values than controls.