• The korean journal of orthodontics
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• v.22 no.1
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• pp.229-239
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• 1992

This study was performed to define the adaptation patterns of each skeletal components to the flexures of cranial bases, using 91 males from the ages of 17 to 36 and 64 females from the ages of 16 to 34, without orthodontic or prosthetic treatment experiences and with pleasant profiles as subjects. The conclusions are as follow: 1. When considering the changes of flexure of cranial base (Ba-SE-FMN) in both sexes, changes in the anterior cranial base angle to the PM Vertical line (SE-FMN/PMV) were greater than the changes in the posterior cranial base angle to the PM Vertical line (Ba-SE/PMV). Subsequently the nasomaxillary complex showed antero-superior rotating effect as the cranial base angles were increased and postero-inferior rotating effect as they were decreased. 2. Horizontal mandibular angle (Ba-SE-Me) was increased in both sexes as cranial base angle increases (Ba-SE-FMN) and it decreased as the latter was decreases. There by indicating compensatory effects. 3. Maxillary angle (SE-FMN-A) was decreased in both sexes as cranial base angle (Ba-SE-FMN) increases and it increased as the latter was decreased. There by indicating compensatory effects. 4. Mandibular ramus angle to posterior cranial base was decreased in both sexes as cranial base angle increases. There by indicating compensatory effect to anteriorly displaced maxilla and the mandibular ramus angle was increased as the cranial base angle decreases. There by indicating compensatory effect to posteriorly displace maxilla. 5. The length of posterior upper facial height was decreased in both sexes as the cranial base angle increases and it increased as the latter was decreased.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.3
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• pp.204-210
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• 2007

This study was intended to compare the cranial base morphology between the mandibular prognathism and maxillary retrognathism in skeletal class III patients. The subject of the present study was composed of 88 patients divided into two groups; Group 1 (Skeletal Class III with mandibular prognathism. SNA within normal range, SNB over normal range, n=54) and Group 2(Skeletal Class III with maxillary retrognathism. SNA below normal range, SNB within normal range, n=34). Lateral cephalogram were taken immediate before surgery and 18 landmarks were used to analyze the characteristics of cranial base and maxillomandibular skeleton. The result revealed that cranial base angle is significantly smaller in Group 1 than Group 2, which implies the influence of the cranial base angulation on the mandibular position. However the posterior cranial base length did not influence the mandibular horizontal position and anterior cranial base length did not influence the maxillary horizontal position. As the anterior cranial base length was closely related with ramal height, it is recommendable to investigate the regulatory mechanism of chondrogenesis of cranial base and condyle cartilage in the future research.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.4
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• pp.379-385
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• 1998

The Holzworth's method was applied to estimate the daily maximum mixing height (DMMH) in Pohang, Osan and Kwangju areas. The data-base were established with meteorological data collected at air bases in these areas during the period 1983∼1992. It was investigated the seasonality, monthly trends and occurrence frequencies of the estimated DMMH data in each area. The estimated mean DMMH were found in the range of 1,100 m (winter) to 1,450m (spring). These mean DMMH data showed a typical seasonality in which higher values are commonly seen during spring and fall, while lower values during summer and winter seasons. An occurrence of estimated mean DMMH which in the range of 1,000∼2,000m altitude was appeared to be about 60%.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.453-458
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• 2009

This paper presents a numerical evaluation of the flow rate of air conditioner outdoor unit as function of shroud design parameters. To determine the optimal design parameters, we investigated the flow rate by changing bell mouth height, fan height, fan guide height, fan width. The evaluation of the relative priority of the design parameters was performed to choose three important parameters in order to use a response surface method. The flow rate of the optimum model, compared to that of the base model, was increased by about 6.25%.

• Journal of Forest and Environmental Science
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• v.31 no.4
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• pp.267-271
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• 2015

The variations of wood density and mechanical properties of Juniperus polycarpos trees were studied in a natural forest in Iran. Sample disks were taken from each tree to examine wood density and mechanical properties (MOE and MOR) from pith to bark at breast height, 50%, and 75% of total tree height. The analysis of variance (ANOVA) indicated that radial position and height significantly affected all wood properties. The wood density, MOE and MOR were decreased along horizontal position from the pith to the bark and vertical direction from base upwards. Regression analysis showed that modulus of elasticity (MOE) and modulus of rupture (MOR) had a positive correlation with wood density.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.11
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• pp.599-605
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• 2009

This paper presents a numerical evaluation of the flow rate of air conditioner outdoor unit by investigating the effects of fan location and shroud shape. To determine optimal design parameters, we investigated the exhaust flow rate by changing shroud height, fan height, fan guide height, and fan width. The 3rd order central composite design was performed to select three most important parameters affecting the exhaust flow rate. According to the result of response surface method, the exhaust flow rate of the optimum model increased by 6.25% compared to that of the base model.

• Journal of the Korean Institute of Navigation
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• v.19 no.1
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• pp.9-16
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• 1995

We are confronted with the serious EMI(electromagnetic interference) problems in company with the development of electronic equipments. Accordingly it is also required to construct some anechoic chambers for EMI measurement. Furthermore it is very important to evaluate the chamber characteristics in advance of its construction. For that purpose we have analyzed the characteristics by computer simulation in base on the image method, and compared the results with the measured ones. In case of 3-meter method as a result, the curved line of height pattern of open site varies similarly as that of height pattern of anechoic chamber. When we measure the electromagnetic strength and can get the height pattern curves by frequencies, we utilized it effectively because we can protect instrumental errors in measurement. On the other hand, there is a little difference in site attenuation above 700MHz. When the ferrite grid was used however, the calculated values agree well with the measured values up to 1000MHz with the exception of 30-40 MHz range. The reason is that we don't consider the antenna coupling in the low frequencies of 30-100MHz range.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.10a
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• pp.273-280
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• 1999

The base shear and the veritcal distribution of shears along the height of a building are two fundamental measures that define the design seismic load. But the method specified in Korean building code does not give an appropriate distribution for buildings of tall or longer period because it roughly account for the contributions of the higher modes. several methods to give a better distribution of seismic forces have been proposed. But they have not been introduced into the seismic codes yet probably because they cannot solve all the above-mentioned problems. This paper deals with the distribution of lateral seismic forces along the height of a building to account for the contribution of the higher modes. After reviewing some existing distributions in seismic codes and literatures moment-resisting frames with various stories were studied by modal analysis for a wide range of fundamental period and the stiffness ratio of the buiding. As a result of the analysis a new expression for the distribution of seismic forces is proposed and compared with those of some codes and dynamic analysis.

• Earthquakes and Structures
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• v.24 no.3
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• pp.155-163
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• 2023

The purpose of this paper is to investigate the coupled effect of SSI and pounding on dynamic responses of unequal height adjacent buildings with insufficiently separation distance subjected to seismic loading. Numerical investigations were conducted to evaluate effect of the pounding coupling SSI on a Reinforced Concrete Frame Structure system constructed on different soil fields. Adjacent buildings with unequal height, including a 9-storey and a 3-storey reinforced concrete structure, were considered in numerical studies. Pounding force response, time-history and root-mean-square (RMS) of displacement and acceleration with different types of soil and separations were presented. The numerical results indicate that insufficient separation could lead to collisions and generate severe pounding force which could result in acceleration and displacement amplifications. SSI has significant influence of the seismic response of the structures, and higher pounding force were induced by floors with stiffer soil. SSI is reasonable neglected for a structure with a dense soil foundation, whereas SSI should be taken into consideration for dynamic analysis, especially for soft soil base.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2003.08a
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• pp.1-9
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• 2003

This paper discusses on recent topics on harbour tranquility base on ship motions. Harbour tranquility is mainly discussed only wave height inside a harbour at the first research period. In these twenty years, researches to improve harbour tranquility have been focused on ship motions to reduce mooring troubles facing to open seas. (omitted)