• Applied Microscopy
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• v.17 no.1
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• pp.1-15
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• 1987

Testes from the allied rock wallaby(Petrogale assimilus) have been examined by the electron microscopy in thin sections in order to examine spermiogenesis and structure of spermatozoa. The spermiogenesis can be divided into nine stages: early Golgi, late Golgi, collapsing, nuclear protrusion, condensation and flattening, nuclear shaping, rotation, nuclear ring contraction, and maturation. The acrosome has been abruptly formed following the collapse of expanded acrosomal vesicle without the cap stage described in the eutheria. The flatly condensed nucleus rotates obliquely to the axis of the axial filament complex and the folded acrosome covers the anterior third of the dorsal nuclear surface forming a wide subacrosormal space as the nuclear ring has contracted. The Sertoli cell reaction and spur are prominent during the nuclear protrusion and rotation stages. A mature spermatozoon has S-shape head which has an extended part reaching to the vicinity of the middle piece.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.1091-1096
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• 2003

Pullout tests of single headed bars using plain concrete blocks indicate that the embedment depth of $10d_b$ is in general required for the headed bars to develop pullout strength equivalent to 125% of bar yield strength. In this experimental study, test results of multiple headed bars installed in reinforced concrete column sections are presented. Test variables included embedment depth, column main reinforcement ratio, and spacing of column ties. 2D29 bars were pulled out at one time from normal strength concrete. Test results indicated that the embedment depths, column tie spacings, and column main reinforcement ratios all influenced the pullout strengths of the headed bars. When the embedment depth was not sufficient, narrow tie spacings especially resulted in increased pullout strengths of the headed bars. Test results also indicated that the embedment depth of 15㏈ was sufficient for the closely spaced two headed bars (head-to-head spacing =$6d_b$) to develop pullout strength equivalent to 125% of the bar yield strength.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.9 s.180
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• pp.2191-2201
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• 2000

End effects due to sectional deformations of thin-walled beams with closed cross section are analysed by a one-dimensional theory. In particular, end effects associated with warping (out of plane m otion) and distortion (in plane motion) are investigated. The exact solutions as a vector form are newly derived to reveal slowly-decaying nature of the end effects in a thin-walled beam loaded by a couple. Several examples of thin-walled beams under various loading conditions indicate that the local end effect zone due to warping and distortion is approximately ten times the typical beam width.

• Rapid Communication in Photoscience
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• v.4 no.3
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• pp.63-66
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• 2015

When the molecule in the excited state is subject to prompt predissociation, it is quite nontrivial to obtain vibrational structure of the excited state in general. This applies to the case of photochemistry of dimethylamine (DMA:$(CH_3)_2NH$). When DMA is excited to its first electronically excited state ($S_1$), the N-H bond dissociation occurs promptly. Therefore, $S_1$ vibronic bands are homogeneously broadened to give extremely small ionization cross sections and heavily-congested spectral features, making infeasible any reasonable spectral assignment. Here, we demonstrate that the predissociation rate of the excited state could be significantly reduced by the NH/ND substitution to give the much better-resolved $S_1$ spectral feature, revealing the vibrational structure of the excited state of $DMA-d_1$ ($(CH_3)_2ND$) for the first time.

• The Academic Congress of Korean Shoulder and Elbow Society
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• 1995.03a
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• pp.46-46
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• 1995

We investigated the reliablity of the ultrasonography for diagnosis of rotatar cuff taers. We prepared histological sections of forty shoulder joints In match the ultrasound planes, and conducted a comparative study of tke two sets of images. hi cases of rotator cuff tear, hyperechogenic and cartilaginfication of the tear site were detected as hyperechogenic foci. On the countrary, the regions in which tendon fibers were decreased or absent showed sonolucent areas. We caluculated the echo level of rotator cuff objectively. The area of abnormal echo level and the other regions located in the same depth of the rotator cuff were defined by ultrasonic equipment. The mein difference in these two echo levels was calculated. The mean difference in patients with rotator cuff tears was larger than that in normal cases. These results indicate that ultrasonography is a useful procedure in many patients with rotator cuff lesions.

• International Journal of Aeronautical and Space Sciences
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• v.14 no.3
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• pp.222-228
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• 2013

A jetfighter shape modeling method based on design features is researched, to improve the efficiency of shape modeling in the stage of conceptual aircraft design. The aircraft's general design features and shape parameters, including geometric and position parameters, are described. The coordinate systems of the entire aircraft and its components are defined. As a sample of local shape, a method of inlet intake modeling is introduced. The whole process of the modeling method is proposed. Three examples of different jetfighters are listed, to describe the achievement of basic layout, which includes four main elements. The Fusion of Components can be achieved by regulating the details of the sections of the fuselage. Sample Cases of typical layouts are shown to verify the effectiveness of the proposed method, which provides the basis for further analysis and optimization.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.04a
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• pp.291-298
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• 2001

When the compression members have the variable cross sections along their member axes, the determination of the elastic critical loads by classical methods becomes impossible and if possible involves complicated calculation only to obtain the approximate values of critical load. In this paper the elastic critical load coefficients of the tapered members with simply supported ends were determined by finite element method. And then the results were represented by simple algebraic equations of two parameters, a( =taper parameter) and m ( = sectional property parameter). One the basis of algebraic equations, the equivalent moment of inertia concept originally proposed by Bleich for a spesific case, are extended to the general cases.

• Journal of the Korean Home Economics Association
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• v.31 no.4
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• pp.95-113
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• 1993

The goal of this study is to try to grasp the general feature, familism, and social support network of the separated family who came south over the border, on them who are residing inland, as a part of the work to clarify the diverse form and specialty that Korean family have. To summarize the result simply is as follows: 1. The difference is showing, between separated family and non-separated family, in the family preference and the consciousness to respect parents, among the range of familism. That is, in case of the separated family, family preference and the consciousness to respect parents showed higher, in comparison with the non-separated family. 2. Between separated family and non-separated family, the difference showed only in the support network of relative. So, the support network of relative of non-separated family showed higher than that of separated family. Through above conclusion, the situation which is the losing native place and the separated which occurred due to war and the dividing into sections is influencing our family life. But, on the other hand, it can be seen that the influence is becoming void gradually.

• Journal of The Korea Institute of Healthcare Architecture
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• v.13 no.2
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• pp.37-44
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• 2007

Rehabilitation medicine is an area which tries to help people who have physical inconvenience in everyday activities to live like healthy people as much as possible by training programs. As society gets more advanced and as the standard of living continuously rises, the need of the "Rehabilitation medicine" is also increasing. Also as we are entering into the aging society, especially geriatric rehabilitation medicine is getting more and more attention as a method to maintain the healthy lives of the elders. However, the standards related to medical care space for rehabilitation medicine is not thoroughly prepared. Although requirement for geriatric hospital is increasing, the standard of geriatric hospital is not following up to regulate them properly. Therefore, in this study, I will propose a 'suitable planning' needed in geriatric rehabilitation by analyzing the rehabilitation sections of 5 general hospitals and 1 geriatric hospital.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.558-564
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• 2006

When vehicles pass the connection between the bridge and earthwork, the difference of both sections' stiffness produces an increasing wheelload. As a consequence, it results in the excessive vibration of vehicles and the damage of bearing system. In general, steel plate girder railway bridges without ballast track have larger stiffness than the bridge with ballast, and produces larger impulse on the bridge superstructure. Thus, it is necessary to reduce the differences of both stiffness. This study presents parametric studies on the behavior of plate girder bridges and their tracks by means of various stiffnesses and the length of approach zone. The results of numerical study showed that the smaller the stiffness of both sides and the longer the length of approach zone, the variation of wheelload becomes smaller. Hence, it gives less burden into the plate girder bridges and their tracks. It is expected that the results of parametric study can be used as a preliminary data for the determination of economical length on the approach zone and the stiffness of both sides.