• The korean journal of orthodontics
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• 제13권1호
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• pp.105-114
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• 1983

the author studied the corelativity between the head and face and the maxillary arch in Korean. This study was undertaker in 336 persons at age from 9 to 19 years who had normal occlusion by means of angle's classification. The following results were obtained. 1. The corelative coefficient between the Height of Head and Face (H.H.F.) and the Arch Length (A.L.) was 0.203-0.543, 2. The corelative coefficient between the Bizygomatic width (Z.W.) and the Bicanine width (C-C) was 0.203-0.543. 3. The corelative coefficient between the Bizygomatic width (Z.W.) and the Bimolar width (M-M) was 0.206-0.600. 4. The corelative coefficient between the Face shape (Index a) and Maxillaxy arch shape (In-dex c) was 0.232-0.404. 5. The corelative coefficient between the Face shape (Index a) and Maxillary arch shape (Index d) was 0.221-0.401. 6. There was no corelativity between the Anterior-posterior width of head (A.P.W.) and Arch Length A.L.), Head shape (Index b) and Maxillary arch shape (Index c, Index d).

• The korean journal of orthodontics
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• 제25권5호
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• pp.593-604
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• 1995

Mandibular incisor crowding is one of the most common features of malocclusion and is interesting characteristic in view of relapse and stability after orthodontic treatment. There are many potential factors in the etiology of lower anterior crowding. The tooth size variation is one of them, but biologic significance for the faciolingual width of the teeth has been overlooked. Peck and Peck reported that persons with ideal mandibular incisor alignment were shown to have incisor with smaller mesiodistal and larger faciolingual dimensions than persons with incisor crowding. On the basis of these findings they suggested MD/FL index as a clinical guideline for the assessment for lower incisor crowding. The present study was undertaken to examine the relationship between mandibular incisor crowding and mandibular incisor dimension, and determine their correlation with arch length discrepancy. 154 dental casts of people from 11 to 17 years of age were made, and were divided into normal group with irregularity index less than of 1, and crowding group with irregularity index greater than 1.The casts were measured and analyzed statistically. The results were as follows. 1. The mean mesiodistal width for mandibular incisor was larger in crowding group, and has significant difference in central inciosr measurement. There are no significant differences in the faciolingul width and MD/FL index. 2. Irregularity index has significant correlation coefficients with mesiodistal width and MD/FL index for mandibular incisor in crowding group, but no correlation with faciolingual width. It also has correlation with maxillary and mandibular arch length discrepancy, total tooth material, mandibular intercanine width, and mandibular inter first premolar width. 3. Upper and lower arch length discrepancy have significant correlation with mesiodistal width of mandibular incisor and overbite, but have no correlation with faciolingual width. Lower arch lenth discrepancy has significant correlation with MD/FL index for mandibular incisor and upper arch length discrepancy has correlation with MD/FL index for mandibular lateral incisor. 4. Significant differences were observed between normal and crowding group for the mandibular arch length discrepancy and overbite.

• Korean Journal of Applied Biomechanics
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• 제19권2호
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• pp.187-196
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• 2009

The foot type is classified into normal, high or low arch according to either foot print or medial longitudinal arch (MLA) height. Plantar fasciitis, heel pain, Achilles tendinitis, stress fracture, metatarsalgia, knee pain, shin splint pain, and etc are common foot disorders and associate to the foot type. The purpose of this study was to evaluate several suggested bony inclination used to classified the abnormal foot and if the arch index (AI) was correlated with foot morphology. Lateral view and dorso-plantar view of radiographic images and flatbed scanner measurements obtained from 57 college students were analyzed. Results showed that AI measured in this study was higher than Caucasian Americans and European, but similar with African. The ethnic origin could influent the AI distribution. The AI provided a simple quantitative means of assessing the structure of lateral and medial longitudinal arches. The correlation coefficients of true bone height with AI could be further improved by normalized foot width rather than foot length. AI also demonstrated as a good indicator of inclination between calcaneus-fifth metatarsal (CalM5) and calcaneus-first metatarsal (CalX), it is a good means to classify the foot type.

• The Journal of Korean Medicine
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• 제29권5호
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• pp.90-95
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• 2008

Objectives : The purpose of this study is to evaluate if there is significant correlations between the angle of costal arch and digestion, and BMI(Body Mass Index). Methods : To know the correlation between digestion and the angle of costal arch, we hand-measured the angle of costal arch and made questionnaire about digestion. We analysed the data with Pearson product-moment correlation analysis using SPSS 12.0. Results : There is proportional correlation between the angle of costal arch and digestion. Also wider costal arch shows better appetite, faster speed of eating and more quantity of meal. And someone having wider costal arch has less digestion disorder after eating heavy foods or being anxious. And there is proportional relation between angle of the angle of costal arch and BMI. Conclusions : There is significant correlation between the angle of costal arch and digestion as wider costal arch can digest better. Also it has proportional relation between the angle of costal arch and BMI. We expect that further study about morphology of abdomen will develop our abdominal examination and diagnostic methods.

• Journal of the Korean Statistical Society
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• 제34권1호
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• pp.61-71
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• 2005

A class of asymmetric ARCH processes is proposed via binary random power transformations. This class accommodates traditional nonlinear models such as threshold ARCH (Rabemanjara and Zacoian (1993)) and Box-Cox type ARCH models(Higgins and Bera (1992)). Stationarity condition of the model is addressed. Iterative least squares(ILS) and pseudo maximum like-lihood(PML) methods are discussed for estimating parameters and related algorithms are presented. Illustrative analysis for Korea Stock Prices Index (KOSPI) data is conducted.

• The korean journal of orthodontics
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• 제26권1호
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• pp.17-32
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• 1996

It is important to understand the operating mechanism and force system of fixed appliance that most effective for individual tooth movement in various orthodontic appliances. The archwire system of fixed appliance is devided into 3 types, which is continuous arch, segmented arch and sectional arch. The last two types have longer interbracket distance and simple force operating points, so it is easy to control force system by operator. But the continuous arch has shorter interbracket distance and various bracket geometry, so it is hard to control and anaylze the force system. The purpose of this study was three dimentional force and moment analysis of continuous arch system by finite element method, which is similar situation to three dimentional elastic beam in structural engineering. Several sample form of various bracket geometry and artificial lower crowding typodont made by author were constructed, analyzed and compared each other. The results were as follows : 1. The force magnitude is linear proportional to the degree of displacement or tilting of the bracket. 2. The force magnitude is inversely non-linear proportional to the interbracket distance. 3. In three dimensional typodont model, while the force can be compared with that of the sample form in the area where adjacent bracket geometry is simple, the force is much more than the expected value in the area where adjacent bracket geometry is complex.

• Steel and Composite Structures
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• 제6권2호
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• pp.87-101
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• 2006

The deformation and dynamic behavior mechanism of submerged shell-like lattice structures with membranes are in principle of a non-conservative nature as circulatory system under hydrostatic pressure and disturbance forces of various types, existing in a marine environment. This paper deals with a characteristic analysis on quasi-periodic and chaotic behavior of a circular arch under follower forces with small disturbances. The stability region chart of the disturbed equilibrium in an excitation field was calculated numerically. Then, the periodic and chaotic behaviors of a circular arch were investigated by executing the time histories of motion, power spectrum, phase plane portraits and the Poincare section. According to the results of these studies, the state of a dynamic aspect scenario of a circular arch could be shifted from one of quasi-oscillatory motion to one of chaotic motion. Moreover, the correlation dimension of fractal dynamics was calculated corresponding to stochastic behaviors of a circular arch. This research indicates the possibility of making use of the correlation dimension as a stability index.

• Journal of Chest Surgery
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• 제54권6호
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• pp.466-472
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• 2021

Background: Major intraoperative hemorrhage reportedly predicts unfavorable survival outcomes following surgical resection for esophageal carcinoma (EC). However, the factors predicting the amount of blood lost during thoracoscopic esophagectomy have yet to be sufficiently studied. We sought to identify risk factors for excessive blood loss during video-assisted thoracoscopic surgery (VATS) for EC. Methods: Using simple and multiple linear regression models, we performed retrospective analyses of the associations between clinicopathological/surgical factors and estimated hemorrhagic volume in 168 consecutive patients who underwent VATS-type esophagectomy for EC. Results: The median blood loss amount was 225 mL (interquartile range, 126-380 mL). Abdominal laparotomy (p<0.001), thoracic duct resection (p=0.014), and division of the azygos arch (p<0.001) were significantly related to high volumes of blood loss. Body mass index and operative duration, as continuous variables, were also correlated positively with blood loss volume in simple linear regression. The multiple linear regression analysis identified prolonged operative duration (p<0.001), open laparotomy approach (p=0.003), azygos arch division (p=0.005), and high body mass index (p=0.014) as independent predictors of higher hemorrhage amounts during VATS esophagectomy. Conclusion: As well as body mass index, operation-related factors such as operative duration, open laparotomy, and division of the azygos arch were independently predictive of estimated blood loss during VATS esophagectomy for EC. Laparoscopic abdominal procedures and azygos arch preservation might be minimally invasive options that would potentially reduce intraoperative hemorrhage, although oncological radicality remains an important consideration.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• 제10권1호
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• pp.103-116
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• 2004

The purpose of this study was to investigate between low back pain scale and disability index owing to gait pattern. For the period of February 1 to February 29, 2004, we had conducted a questionnaire and direct interview with 100 persons lived in Daejeon. The result were as follows: 1. The stride length of experimental group. the male was $49.9{\pm}12.9cm$. the female $45.7{\pm}12.9cm$ and the width of feet, the male was $13.5{\pm}5.7cm$, the female $12.2{\pm}4.8cm$. 2. The Fick angle of all subjects was showed in external disposition, the left angle showed in asymmetry, the male was $11.0{\pm}5.7^{\circ}$, the female $8.5{\pm}1.3^{\circ}$. 3. The foot arch was similar to sex as a weight bearing and non-weight bearing, the male was $1.3{\pm}0.8cm$, the female $1.3{\pm}0.9cm$. 4. The impedimental index according to back pain grade, men was a lower than women, the male was $5.7{\pm}6.9$ and the female $7.2{\pm}5.3$. 5. The relation to difference between foot arch and disability index according to back pain grade as a weight bearing and non-weight bearing, the higher foot arch, the higher back pain grade was statistically significance(p<.05). 6. The relation between width of feet and disability index according to back pain grade, the wider width of feet, the higher back pain grade was statistically significance(p<.01). 7. The relation between stride length and disability index according to back pain grade, the wider stride length, the higher back pain grade was statistically significance(p<.05).

• The Journal of Asian Finance, Economics and Business
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• 제8권2호
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• pp.57-64
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• 2021

This research attempts to formulate a new mean-risk model to replace the Markowitz mean-variance model by altering the risk measurement using ARCH variance instead of the original variance. In building the portfolio, samples used are closing prices of Indonesia Composite Stock Index and Indonesia Composite Bonds Index from 2013 to 2018. This study is a qualitative study using secondary data from the Indonesia Stock Exchange and Indonesia Bonds Pricing Agency. This research found that Markowitz's model is still superior when utilized in daily data, while the mean-ARCH model is appropriate with wider gap data like monthly observation. The Historical return has also proven to be more appropriate as a benchmark in selecting an optimal portfolio rather than a risk-free rate in an inefficient market. Therefore Mean-ARCH is more appropriate when utilized under data that have a wider gap between the period. The research findings show that the portfolio combination produced is inefficient due to the market inefficiency indicated by the meager return of the stock, while bears notable standard deviation. Therefore, the researcher of this study proposed to replace the risk-free rate as a benchmark with the historical return. The Historical return proved to be more realistic than the risk-free rate in inefficient market conditions.