• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.1
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• pp.25-32
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• 2005

In this paper, it is attempted to provide a unified explanation for typical short channel GaAs MESFET’s and SOI-structured Si JFET's behaviors such as: i) drain voltage-induced threshold voltage roll-off, ii) finite output ac resistance beyond the saturation, and iii) weak dependence of the drain saturation current on the channel length. Replacing the conventional GCA with a new assumption that is suggested in order to include the longitudinal field variation, and taking into account the channel current continuity and the field-dependent mobility, we can derive the two-dimensional potential in both depletion region and undepleted conducting channel. Obtained expressions for the threshold voltage and the drain current will be considerably accurate over the entire operating region. Moreover, in comparison with the conventional channel length shortening models, our model seems to be more reasonable in explaining the Early effect.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.55 no.3
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• pp.141-145
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• 2006

The line current problem(2-dimensional space : point source) is not easy to analyze the magnetic field using the standard finite element method(FEM), such as overhead trolley line or transmission line. To supplement such a defect this paper is proposed the coupling scheme of analytical solution and FEM. In analysis of the magnetic field using the standard FEM. If the current region is a relatively small compared to the whole region. Therefore the current region must be finely divided using a large number of elements. And the large number of elements increase the number of unknown variables and the use of computer memories. In this paper, an analytical solution is suggested to supplement this weak points. When source is line current and the part of interest is far from line current, the analytical solution can be coupling with FEM at the boundary. Analytical solution can be described by the multiplication of two functions. One is power function of radius, the other is a trigonometric function of angle in the cylindrical coordinate system. There are integral constants of two types which can be established by fourier series expansion. Also fourier series is represented as the factor to apply the continuity of the magnetic vector potential and magnetic field intensity with tangential component at the boundary. To verify the proposed algorithm, we chose simplified model existing magnetic material in FE region. The results are compared with standard FE solution. And it is good agreed by increasing harmonic order.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.869-872
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• 2005

The purpose of this study is on the prediction of the acoustic performance of the lined rectangular plenum chamber which can be used in the HVAC systems. The lined plenum chamber is modeled as a piston driven rectangular tube without mean flow and the acoustic pressure in the lined chamber is obtained by superposing the three dimensional pressure due to each of uniformly and harmonically fluctuating pistons. The arbitrary locations of inlet/outlet ports as well as the acoustic higher order modes generated at the area discontinuities of the port chamber interfaces are taken into consideration. The four-pole parameters can be derived by imposing the proper boundary conditions on each inlet and outlet ports. The lining material on the internal wall is assumed to be a bulk-reacting model. A single weak variation statement which satisfies the fluctuating rigid piston condition and the pressure and displacement continuity condition at the interface between the lining material and the airway was developed. The set of cosine functions were used as the admissible function when applying the Rayleigh-Ritz method. Computed results are compared with those predicted by using the locally-reacting lining material and experimental results, respectively. There are a good agreement shown between the results by the Rayleigh-Ritz method and the experiment results. The derived transfer matrices can be easily combined with other four-pole parameters of different types of mufflers for the calculation of the whole system performance.

• Journal of Chest Surgery
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• v.9 no.2
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• pp.245-250
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• 1976

A 33 year-old man was admitted with chief complaints of severe sharp pain on left upper interscapular region and motor weakness of left arm for 9 days. He had a history of blunt trauma over left shoulder about 3 years ago. Physical examination showed a ping pong ball sized mass which was located at the left supraclavicular area and was firm, fixed, and nonpulsatile. No bruit or murmur was obtained over the mass. Ipsilaterally, radial, ulnar, and brachial pulse were very weak and ptosis and anhidrosis were noticed. Neurologic examination revealed moderate or severe weakness of flexion and extension of left elbow, wrist and fingers, and anesthesia of the skin in left C8-T1 dermatome and hypalgesia in left C6-C7 dermatome. Retrograde aortography demonstrated complete obstruction of left subclavian artery. An exploratory operation was performed through the left 4th intercostal space. It was found that the mass was a left subclavian aneurysm of traumatic false type. Proximal and distal ligation of the aneurysm were applied and the sac was partially removed. The continuity of the subclavain artery was established by the use of a 6mm. Dacron graft from the root of the subclavian to the axillary artery. Postoperatively the patient was improved from the circulatory and neurologic disturbances.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.1 s.108
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• pp.33-48
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• 2005

The purpose of this study was to discover the landscape visual image of the slope scene and their harmony with surrounding sceneries. This research utilized the basic study tool of psycho-physics and processed the case study of ten types of slope construction scene along the highway. The analysis was performed by the data obtained from the questionnaires and the photos for the slope construction scene. The questionnaires for analysis the image of the slope construction scene and their harmony with surrounding sceneries were designed using semantic differential scale and 5 point Likert-scale. The major findings were as follows. 1. At the part of the visual preferences analysis, the slope revegetation methods showed high level of preferences generally than on the slope structure methods. While the slope revegetation methods were estimated friendly, continuity, harmonious, soft, light and wide, the slope revegetation methods were estimated unstable, female, static, simple, omnipresent, appeared as policeman of weak inclination. Also the slope structure methods were estimated stable, manly, complicated, steep and healthy but rough, unharmonious, unfamiliar and heavy. 2. Psychological factors, related to the satisfaction for the slope revegetation methods were composed of three factors, aesthetic, individuality and physical character. And the slope structure methods were composed of five factors, aesthetic, individuality, stability, physical character, and complexity. 3. At the part of harmony with surrounding landscapes, the slope revegetation methods were evaluated highly but the slope structure methods received the lowest evaluation. Also the harmony analysis with surrounding view on the slope revegetation methods showed degree of high more than average in all texture, form, color and scale but the slope structure methods showed degree of fewer than average degree in form, scale, color and texture.

• The Journal of the Korea Contents Association
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• v.20 no.10
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• pp.76-88
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• 2020

Since the pre-existing music itself used in has no direct relation to the film, it raises the question of whether it was properly utilized as film music. The purpose of this paper is to clarify that 's 20th century modern music effectively fulfills the role of film music through iconicity with images. This study approached the similarity between the character of fear and the form of music through Hanslick's formal aesthetics to discuss the use of 20th century modern music in the horror film. The formal characteristics of music are observed in the movement of notes, which are similar to the fearful state of mind mentioned by Heidegger. In the analysis, the stagnant movement and the continuity of notes, the special playing method of the musical instrument, the unspecified trembling of the clustered notes, the melody of the weak intensity in the high-pitched range, the smash of percussions, and the progression of the notes that deviate from the center confirms the aptitude of 20th century modern music in the horror film. The fact that this study did not simply rely on the emotions represented in the 20th century modern music, but thoroughly caught the movements of the notes, has great significance in the research of film .

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.5
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• pp.53-60
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• 2020

In this study, smart precast-in-place concrete, such as continuity with Precast any technology that can be the Application of Building Structures and railway stations, civil structures. After the same way in the field installation design based on the criteria railways and derived the right section, through the Static and Dynamic Response Analysis. Dynamic sensor and the triaxial acceleration measured by attaching the sensor acceleration response according to the extent of the damage of Precast Panel Structures and mode of Precast Structures, by comparing the data. Data for the stability and improvement of the uncertainty in along a railroad and Future of Precast Panel Structures of time to replace. This is to use this data as basic data on damage prediction.

• Structural Engineering and Mechanics
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• v.85 no.6
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• pp.793-808
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• 2023

Türkiye is located in a region where destructive earthquakes are frequently experienced due to its geological characteristics and geographical location. Therefore, considering the possibility of a devastating earthquake at any time, determining the reinforced concrete (RC) building seismic safety, constructed before or after the current seismic buildings code, is one of the most important issues to be completed firstly. For this purpose, rapid assessment methods developed to quickly determine the seismic safety of buildings are available in the literature. Comparison of the principles of Principles of the Determination of Risky Structures-2019, Column and Wall Index Method, P25 Scoring Method and Improved Discriminant Analysis Method, which are among these methods, have been aimed within the scope of this study. Within the scope of this paper, a total of 43 buildings in the Yalova/Çınarcık region of Türkiye that the damage level was determined by street observation method immediately after the 1999 Kocaeli (Izmit) Earthquake; 15 buildings with heavy damage and 28 buildings with moderate damage were examined by rapid assessment methods. Although the risk detection difference was not separated as a clear line in any of the methods used, the results obtained from the rapid assessment methods are evaluated as being compatible with the detected after earthquake structural seismic behavior of the buildings. The PDRS-2019 and column and wall index method gave the most approximate results. In the results obtained from the analyzes; structural features such as number of floors, frame continuity, soft/weak story irregularity, effective shear strength area, existence of heavy overhangs in plan, type of structural system have been found to be significantly effective on the earthquake behavior of buildings.

• Structural Engineering and Mechanics
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• v.86 no.3
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• pp.291-309
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• 2023

This paper addresses the finite element modeling of functionally graded porous (FGP) beams for free vibration and buckling behaviour cases. The formulated finite element is based on simple and efficient higher order shear deformation theory. The key feature of this formulation is that it deals with Euler-Bernoulli beam theory with only three unknowns without requiring any shear correction factor. In fact, the presented two-noded beam element has three degrees of freedom per node, and the discrete model guarantees the interelement continuity by using both C⁰ and C¹ continuities for the displacement field and its first derivative shape functions, respectively. The weak form of the governing equations is obtained from the Hamilton principle of FGP beams to generate the elementary stiffness, geometric, and mass matrices. By deploying the isoparametric coordinate system, the derived elementary matrices are computed using the Gauss quadrature rule. To overcome the shear-locking phenomenon, the reduced integration technique is used for the shear strain energy. Furthermore, the effect of porosity distribution patterns on the free vibration and buckling behaviours of porous functionally graded beams in various parameters is investigated. The obtained results extend and improve those predicted previously by alternative existing theories, in which significant parameters such as material distribution, geometrical configuration, boundary conditions, and porosity distributions are considered and discussed in detailed numerical comparisons. Determining the impacts of these parameters on natural frequencies and critical buckling loads play an essential role in the manufacturing process of such materials and their related mechanical modeling in aerospace, nuclear, civil, and other structures.

• Journal of the Daesoon Academy of Sciences
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• v.26
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• pp.111-142
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• 2016

'In-Jon(人尊)' is one of a concept which constitute the mainstay of Daesoon thought. To be superficial, the concept is appeared to be limited at a area of anthropology, but In-Jon is a large concept which includes ontology and epistemology. Because the essence of human being is connected with God and the such possibility is related to the mission of human being's subject who exists in world. Advanced researches to analysis of in-jon tend to focus on rise of human status but this study do on universal subject not particular subject. This is to elaborate the point of issue. The point of view as rise of human status overlooks problem of relationship between human entities. who ingenerate hierarchy. In-jon is the universal subject of philosophical subject concepts which western philosophy have taken as main problem since Descartes. So we have to consider In-jon to be conceptual continuity concerning stream of history of ideas and communicate with ideas. A precedent study on 'injon' concept has weak conceptual analysis, which only emphasizes the greatness of mankind as compared with others. But that can't reveal In-jon based on the Daesoon thought. So I try to engraft the concept on development of subject ideas to get academic objectivity. In-jon is great in having universal subject to expand the authority of God to all creation. That is the last goal which subject can reaches through the development. Considering this regard the research direction of this study is very encouraging and significant. Western philosophy has important philosopher of the three, Descartes, Kant, Hegel. Those are a spectrum who show an aspect of subject ideas. The subject idea has become the middle of philosophical system since Descartes in modern. It is the right and necessary process to philosophy because human being has spirit or reason connected with God. So In-jon in Daesoon thought is academic concept comprising ontological and epistemological properties. So I try to analyse In-jon through that and have In-jon join the ranks of mainstream academics in this paper