• The Bulletin of The Korean Astronomical Society
• /
• v.37 no.1
• /
• pp.87.1-87.1
• /
• 2012

We use three-dimensional magnetohydrodynamic simulations to investigate how the dynamic state of emerging magnetic field is related to the twist of field lines. Emergence of magnetic field is considered as one of the key physical process producing solar activity such as flares, jets, and coronal mass ejections. To understand these activities we have to know dynamic nature and electric current structure provided by emerging magnetic field. To demonstrate dynamic nature of field lines, we focus on the factors such as curvature of magnetic field line and scale height of magnetic field strength. These factors show that strong twist case forms two-part structure in which the central part is close to a force-free state while the outer marginal part is in a fairly dynamic state. For weak twist case, it still shows two-part structure but the tendency becomes weaker than strong twist case. We discuss how the curvature distribution affects the dynamic nature of emerging magnetic field. We also investigate electric current distribution provided by emerging field lines to show a possible relation between electric current structure and sigmoid observed in a preflare phase.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.26 no.4
• /
• pp.135-143
• /
• 1999

This study is about the pattern of spatial structures of major university campuses in Korea. The pattern is composed of buildings, circulation, and open space within the campus. It is physical structural system which makes campus more educational environment as well as new academic landscape. The pattern is checked on the basis of existing sub-patterns of eleven universities with base data by using computer program, Autocad and Landcadd. The result is that most of campus spatial structures consists of simple and unified grid pattern. Basic educational facilities are at the center of the whole structure as well. Some universities are located in suburb and have large site which makes it more open space oriented pattern, more various exterior space and more specific circulation system. So the campus patterns of recently built is more diverse and has more design components. In most cases, campus does not have strong spatial coherence among its buildings, circulation, and open space. It is important to develop Korean formal campus spatial structure which is intrinsic to its site and is proper to its academic plan. Campus spatial structure should be formulated to embrace diverse demands of university and to accumulate unique university landscape.

• Journal of Korean Association for Spatial Structures
• /
• v.18 no.3
• /
• pp.75-82
• /
• 2018

Large space structures exhibit different natural vibration characteristics depending on the aspect ratio of structures such as half-open angle. In addition, since the actual large space structure is mostly supported by the lower structure, it is expected that the natural vibration characteristics of the upper structure and the entire structure will vary depending on the lower structure. Therefore, in this study, the natural vibration characteristics of the dome structure are analyzed according to the natural frequency ratio by controlling the stiffness of the substructure. As the natural frequency of the substructure increases, the natural frequency of the whole structure increases similarly to the natural frequency of the upper structure. Vertical vibration modes dominate at $30^{\circ}$ and $45^{\circ}$, and horizontal vibration modes dominate at $60^{\circ}$ and $90^{\circ}$.

• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 2000.10a
• /
• pp.348-355
• /
• 2000

The characteristics on non linear behavior and the failure mechanism of RC space frame structure serving railway under seismic action have been investigated by numerical analysis in time domain. The structure concerned is modeled in 3 dimensional extent and RC frame elements with fibers are employed. Fibers are characterized as RC one and PL one to distinguish different energy release after cracking. Due to deviation of mass center and stiffness center of entire structure the complex behavior under seismic action is shown. The excessive shear force is concentrated on the pier beside flexible one relatively, which leads to failure of bridge concerned.

• Korean Institute of Interior Design Journal
• /
• v.15 no.6 s.59
• /
• pp.205-212
• /
• 2006

The premise of this study is that an ultimate objective in planning an exhibition space is spectators' experiences shaped by a result of their first-hand experiences and responses within an exhibition space, and this result can be recognized in the spectators' movement. Thus, the sign system that can directly affects viewers' main line of flow and movement patterns was examined vis--vis a mutually complementary relation in a triangular composition with the structure of exhibition space and the exhibition contents. Based on the findings, predictive values before and after a complementary application of the sign system to the structure of exhibition space was analyzed and its validity was assessed. The results of this research analysis were drawn as follows. It was shown that an understanding of the locations of direction signs and the degree of recognition can function as an important factor to predict viewers' movement, along with an understanding of topological characteristics of an exhibition space. In terms of the connection and disconnection of space units that form the space structure, it suggests that the distribution of signs and the degree of recognition can adjust the degree of connection and disconnection. Even though exhibition spaces for research subjects were selected from a relatively large number of museums, but the research was limited with a focus on the structure of exhibition space and sign systems. Thus, it is proposed that future studies should be conducted by including varieties of exhibition and environmental factors.

• East Asian mathematical journal
• /
• v.37 no.1
• /
• pp.97-107
• /
• 2021

Let M be a real hypersurface with almost contact metric structure (��, ξ, ��, g) in a nonflat complex space form Mn(c). We denote S and Rξ by the Ricci tensor of M and by the structure Jacobi operator with respect to the vector field ξ respectively. In this paper, we prove that M is a Hopf hypersurface of type (A) in Mn(c) if it satisfies Rξ�� = ��Rξ and at the same time satisfies $({\nabla}_{{\phi}{\nabla}_{\xi}{\xi}}R_{\xi}){\xi}=0$ or Rξ��S = S��Rξ.

• Korean Institute of Interior Design Journal
• /
• v.24 no.2
• /
• pp.142-150
• /
• 2015

The purpose of this study is to analysis the change of rural house type and house plans in Bonghwa province. According to definition of rural area, the scopes of the research of rural houses limited the Bonghwa rural area(1 eup, 9 myeon). The method of study is to compare and analyze about housing situation, structure of house, housing type and construction of house space etc. through the statistical data of Bongwha statistical yearbook, space syntax(convex analysis) and other various data etc. during these 10 years. As a results of the analysis 1) According to Change of family member the supply ratio of detached house is steadily decreasing and changing from a detached house to multi-household house in Bongwha areas. 2) Most of houses structure were using lightweight steel construction because of cost-cutting of construction and easy way to construct etc.. 3) The highest Integration space is living space in rural house plans 4) The highest segregation space is bathroom space of master bed room in rural house plans. Some of bed rooms are classed as segregation space regardless of Integration space 5) Traditional front yard's function is changing from the place with the various functions to the place with the specific functions.

• Journal of architectural history
• /
• v.22 no.6
• /
• pp.7-22
• /
• 2013

The purpose of this paper is to study on the spatial characteristics from the "The Holy Trinity" fresco painted by Masaccio in the early Renaissance paintings. The results of this study are as follows. 1. The elevation composition of the "The Holy Trinity" fresco is divided into the upper and lower structure through horizontal axis on horizontal line around vanishing point. The upper structure is composed of vertical axis formed through the disposition of the "Trinity" elements and horizontal axis on horizontal line. The lower structure is composed of the sarcophagus and skeleton in such inside and the altar supported through circular columns of left and right. 2. The section composition of the "The Holy Trinity" fresco is composed of the ceiling structure of cylindrical-shaped vault on upper part around basic square floor plan that is interior space and upper structure. The exterior space and lower structure is placed with sarcophagus in inner part that altar and step is projected as same height and width in the outside direction. 3. The basic floor composition of the "The Holy Trinity" fresco is planned by square shape around structural columns that is placed at corners as symmetry through transverse, longitudinal and diagonal axis. The whole floor composition planned through the altar and step that is in exterior space at front, the apse of round form at rear part and the structure of the middle story concept at interior. 4. The visual aspect of the "The Holy Trinity" fresco is composed of the stable balance in relation with distance and height because the interior and exterior space as well as the upper structure and lower structure is formed by regular proportion system. The elevation angle of visual range was planned to view in detail generally or partially the architectural composition system and element, characters through proper visual distance, center and position.

• Journal of Astronomy and Space Sciences
• /
• v.25 no.4
• /
• pp.335-346
• /
• 2008

Using the global total electron contents (TEC) measured by the TOPEX satellite from Aug. 1992 to Oct. 2005, we investigate the variations of the longitudinal wavenumber-4 (LW-4) structure in the equatorial anomaly (EA) crests with season, local time, and solar activity. Our study shows that the LW-4 structure in the EA crests ($5{\sim}20^{\circ}$ MLAT in both hemispheres) has clear four peaks at fixed longitude sectors during the daytime for both equinoxes and June solstice. In spite of being called a wavelike structure, however, the magnitudes and spatial intervals of the four peaks are far from being the same or regular. After sunset, the four-peak structure begins to move eastward with gradual weakening in its amplitude during equinoxes and this weakening proceeds much faster during June solstice. Interestingly, the longitudinal variations during December solstice do not show clear four-peak structure. All these features of the LW-4 structure are almost the same for both low and high solar activity conditions although the ion densities are greatly enhanced from low to high solar activities. With the irrelevancy of the magnetic activity in the LW-4, this implies that the large changes of the upper atmospheric ion densities, one of the important factors for ion-neutral interactions, have little effect on the formation of the LW-4 structure. On the other hand, we found that the monthly variation of the LW-4 is remarkably similar to that of the zonal component of wavenumber-3 diurnal tides at low latitudes, which implies that the lower atmospheric tidal forcing, transferred to the upper atmosphere, seems to have a dominant role in producing the LW-4 structure in the EA crests via the E-region dynamo.

• Journal of the Korean housing association
• /
• v.10 no.2
• /
• pp.175-183
• /
• 1999

This study aims at modeling the compositional method in the architectural space and shape. The composition of space is composed of the position and the area in space. Therefore these elements are established to the functional program applied at the behavioral data. The element of spatial structure is position and scale in space, and the composition of spatial shape is developed repitionally to the combination of build-up method. The functional program is being expertised and the scale in building being lager, the importance of functional program is increased. Applied at data of the functional program at spatial structure, the process is developed to the method of combination. The purpose of this study is approached at the degree of application in modeling on the compositional method in architectural space and shape, which is a fundamental aspect on the quantitative analysis of architectural space.