• 대한치과교정학회지
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• 제44권2호
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• pp.54-61
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• 2014

Objective: This study aimed to propose clinical guidelines for placing miniscrew implants using the results obtained from 3-dimensional analysis of maxillary anterior interdental alveolar bone by cone-beam computed tomography (CBCT). Methods: By using CBCT data from 52 adult patients (17 men and 35 women; mean age, 27.9 years), alveolar bone were measured in 3 regions: between the maxillary central incisors (U1-U1), between the maxillary central incisor and maxillary lateral incisor (U1-U2), and between the maxillary lateral incisor and the canine (U2-U3). Cortical bone thickness, labio-palatal thickness, and interdental root distance were measured at 4 mm, 6 mm, and 8 mm apical to the interdental cementoenamel junction (ICEJ). Results: The cortical bone thickness significantly increased from the U1-U1 region to the U2-U3 region (p < 0.05). The labio-palatal thickness was significantly less in the U1-U1 region (p < 0.05), and the interdental root distance was significantly less in the U1-U2 region (p < 0.05). Conclusions: The results of this study suggest that the interdental root regions U2-U3 and U1-U1 are the best sites for placing miniscrew implants into maxillary anterior alveolar bone.

• 폴리머
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• 제24권6호
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• pp.794-801
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• 2000

Static 용융 삽입에 의하여 열가소성 고분자의 나노복합체를 제조할 때 유기화 점토에 치환된 유기화제의 길이와 packing 밀도, 그리고 열처리 온도와 시간 등이 고분자의 점토 층간 삽입에 미치는 영향에 대하여 x-ray와 FTIR spectroscopy를 이용하여 조사하였다. 초기 유기화제의 배열형태가 lateral monolayer일 때는 고분자들의 용융 삽입이 일어나지 않았으며 그 외의 경우 유기화제의 종류 및 구조 등에 따라 최종 점토 층간 간격은 큰 변화를 보이지 않았다. 열처리 시간에 따라서 층간 간격은 증가하며 더욱 규칙적으로 변하는 것을 알 수 있었고, 온도가 증가함에 따라서는 점토 층간 간격은 증가하지만 불규칙적으로 배열이 되어가는 것을 관찰하였다.

• Journal of Oral Medicine and Pain
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• 제41권2호
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• pp.41-47
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• 2016

Purpose: The purpose of this study was to analyze the size and morphology of mandibular condyle and mandibular fossa between temporomandibular joint (TMJ) disc displacement (DD) patients and healthy subjects using cone-beam computed tomography (CBCT). Methods: Twenty healthy subjects and twenty TMJ DD patients participated in this study respectively. We made five measurements in mandibular condyle (medio-lateral dimension, antero-posterior dimension, condyle height, intercondylar distance and intercondylar angle) and two measurements in mandibular fossa (mandibular fossa depth and articular eminence angle) using CBCT image. Results: There was no difference between two groups in medio-lateral dimension. In case of antero-posterior dimension, average of healthy controls was larger than that of TMJ DD patients, but that was not significant statistically. There were no significant differences between two groups in condyle height. Comparing intercondylar distance and intercondylar angle between two groups, there was no significant difference between two groups. In comparison of mandibular fossa depth and articular eminence angle, there was no significant difference between two groups. Conclusions: We couldn't find any definite relationship between TMJ morphology and TMJ DD.

• Anatomy and Cell Biology
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• 제57권3호
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• pp.346-352
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• 2024

Studies reveal variations in the in the origin, number, and branching patterns of the lateral circumflex femoral artery (LCFA). The present study aimed to document such variations and their potential clinical applicability. Thirty-two femoral triangles of 16 embalmed adult human cadavers were dissected to investigate the variation in the origin, number, and branching patterns of LCFA. The main branches of the LCFA were tracked independently for numerical variations in branching pattern. The distance between the origin of LCFA and mid inguinal point (MIP) was also measured in each case. LCFA was most commonly arising from profunda femoris (PF), followed by femoral artery (FA) and common trunk of the femoral artery (CFA). Duplication LCFA was observed in 15 (46.87%) limbs, in 5 (31.25%) cases duplication was only on right side, in 4 (25%) cases duplication was only on left side and in 3 (18.75%), duplication was bilateral. Cases with duplication of LCFA, showed numerical variations with descending pattern being the most common. The average distance of LCFA1 and LCFA2 from mid-inguinal point was 5.77±1.35 cm and 6.14±2.05 cm respectively. Detailed information regarding the occurrence of duplication will be great importance for surgeons, interventional radiologists, and other medical professionals performing procedures in the femoral region. Knowledge of variation of branching pattern of LCFA is utmost important as surgeons use the descending branch of the LCFA in bypass grafting and vascular reconstruction surgeries.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1992년도 추계학술대회논문집
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• pp.77-83
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• 1992

The effect of magnetic field on VDT work has not been clarified yet, but many studies repoerted that magnetic field could cause of the cancers. Many developed countries have set the criteria of magnetic field and produce the VDT which has lower magnetic value. The purpose of this study was to measure the intensity of magnectic field from VDT. For this purpose three experiments were performed. The first was designed to measure the intensity of magnetic field by distances(30,60,90 cm) and directions. The second was to compare the intensities between VDT and Color TV. The last was to evaluate the eye protec- tion glasses. The reults showed that the intensity of magnetic field was lowered in proportion to the distance $r^{3}$and both lateral sides of the VDT marked high values compared to the frontal and back sides. On the same distance (30 cm) color TV marked high value to the VDT. But on the normal work distance (TV: 100 cm, VDT: 30 cm) there was little difference, Eye protection glasses could not protect the magnetic field physically.

• Archives of Plastic Surgery
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• 제32권6호
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• pp.706-709
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• 2005

The absence of the nipple-areolar complex(NAC) in men are seldom stated, as a result of trauma, burn, mastectomy, or after the correction of extreme bilateral gynecomastia. A total of 50 healthy men aged 21 to 27 years were examined. We recorded the configuration (dimensions and shape) and the location of the NAC with respect to fixed skeletal anatomic landmarks. Of the 50 subjects examined, 44 had oval and 6 had a round NAC. The mean diameter for a round NAC was 24.3 mm. The center of the NAC was in the fourth intercostal space in 41 volunteers and in the fifth intercostal space in 9 of the subjects. To localize the NAC on the chest wall, at least three reproducible measurements proved to be necessary, composed of a horizontal line(distance from the midsternal line to the nipple, A), a medial oblique line(distance from the sternal notch to the nipple, B) and a lateral oblique line(distance from the acromioclavicular joint to the nipple, C). Using these three parameters, we recommend that the appropriate location can be calculated derived from the circumference of the chest.

• Coupled systems mechanics
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• 제1권1호
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• pp.59-78
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• 2012

The available analytical methods of analysis for laterally loaded piles in level ground cannot be directly applied to such piles in sloping ground. With the commercially available software, the simulation of the appropriate field condition is a challenging task, and the results are subjective. Therefore, it becomes essential to understand the process of development of a user-framed numerical formulation, which may be used easily as per the specific site conditions without depending on other indirect methods of analysis as well as on the software. In the present study, a detailed three-dimensional finite element formulation is presented for the analysis of laterally loaded piles in sloping ground developing the 18 node triangular prism elements. An application of the numerical formulation has been illustrated for the pile located at the crest of the slope and for the pile located at some edge distance from the crest. The specific examples show that at any given depth, the displacement and bending moment increase with an increase in slope of the ground, whereas they decrease with increasing edge distance.

• Applied Microscopy
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• 제52권
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• pp.8.1-8.7
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• 2022

The Korean trident goby, Tridentiger brevispinis, lives in adverse habitats that can easily become hypoxic due to low precipitation, regional dry periods, and high amounts of solar radiation. Histological and morphometric studies revealed the goby's specialized skin (35.4-150.0㎛ in thickness), consisting of an epidermis and dermis. The thicker epidermis comprises an outermost surface layer (having taste buds, stratified fattened cells, mucous cells, pigment cells, and stratified polygonal cells), middle layer (having stratified polygonal cells), and stratum germinativum (stratified columnar cells). In particular, the dermis has scales, well-developed vascularization, and a few blood capillaries just above the basement membrane, and a reduced diffusion distance was present in the lateral body. Consequently, adaptations such as thicker epidermis, well-developed vascularization, few blood capillaries, and a reduced diffusion distance may provide cutaneous respiration for survival in poorly oxygenated water during the periodic dry season.

• Archives of Plastic Surgery
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• 제42권2호
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• pp.226-231
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• 2015

The aim of this study is to consider breast imagery in art as depicted through western painting. Twenty western art paintings were collated. Most of the sample paintings were created from the mid-nineteenth century to the late twentieth century and some are from the Renaissance period. Ten anthropometric items were used to measure 15 distances between two landmarks and 3 angles between three points. The distance from the nipple to the sternal notch and to the midclavicular point was the same and they were 0.46 of the distance from the sternal notch to the umbilicus. The shape of the projection of the breast was almost an isosceles triangle and the altitude of the triangle was at a proportion of 0.45 of the bottom length and 0.16 of the distance from the sternal notch to the umbilicus. The distance between the lateral ends of the breasts was 2.14 times the facial width and the distance between nipples was 1.36 times the facial width. Proportions from works of art are more ideal and attractive than clinically measured proportions. The desirable ratios measured from historical paintings might be useful in planning breast surgeries.

• Structural Engineering and Mechanics
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• 제78권2호
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• pp.219-230
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• 2021

International seismic codes stipulate that adjacent buildings should be separated by a specified minimum distance, otherwise the pounding effect should be considered in the design. Recent researches proposed an alternative method (Double Difference Combination Rule) to estimate seismic gap between structures, as this method considers the cross relation of adjacent buildings behavior during earthquakes. Four different criteria were used to calculate the minimum separation distance using this method and results are compared to the international codes for five separation cases. These cases used four case study buildings classified by different heights, lateral load resisting systems and fundamental periods of vibrations to assess the consistency in results for the alternative methods. Non-linear analysis was performed to calculate the inelastic displacements of the four buildings, and the results were used to evaluate the relation between elastic and inelastic displacements due to the ductility of structural elements resisting seismic loads. A verification analysis was conducted to guarantee that the separation distance calculated is sufficient to avoid pounding. Results shows that the use of two out of the four studied methods yields separation distances smaller than that calculated by the code specified equations without under-estimating the minimum separation distance required to avoid pounding.