• International Journal of Aeronautical and Space Sciences
• /
• v.18 no.1
• /
• pp.91-98
• /
• 2017

Performance of a low speed axial compressor is enhanced through a proper configuration of blade row tip injection and casing treatment of groove type. Air injectors were mounted evenly spaced upstream of the blade row within the casing groove and were all aligned parallel to the compressor axis. The groove, which covers all the blade tip chord length, extends all-round the casing circumference. Method of investigation is based on solution of the unsteady form of the Navier-Stokes equations utilizing $k-{\omega}$ SST turbulence model. Extensive parametric studies have been carried out to explore effects of injectors' flow momentums and yaw angles on compressor performance, while being run at different throttle valve setting. Emphasis has been focused on situations near to stall condition. Unsteady numerical analyses for untreated casing and no-injection case for near stall condition provided to discover two well-known criteria for spike stall inception, i.e., blade leading edge spillage and trailing edge back-flow. Final results showed that with only 6 injectors mounted axially in the casing groove and at yaw angle of 15 degrees opposite the direction of the blade row rotation, with a total mass flow rate of only 0.5% of the compressor main flow, surprisingly, the stall margin improves by 15.5%.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.34 no.11
• /
• pp.42-46
• /
• 2006

As an application of SDINS/GPS integration for its synergistic results, the SDINS alignments utilizing GPS carrier phase rate measurements. A measurement model of GPS carrier phase rate is derived in order to be used with SDINS alignment process. For in-flight alignment, the performance of the suggested SDINS/GPS integration method is analyzed using the covariance analysis and its results are confirmed by those of van test. Consequently, it is shown that all states of the SDINS integrated system by utilizing GPS carrier phase rate measurements can be estimated more efficiently than a general SDINS/GPS during in-flight alignment.

• New & Renewable Energy
• /
• v.18 no.3
• /
• pp.60-71
• /
• 2022

A wind tunnel provides artificial airflow around a model throughout the test section for investigating aerodynamic loads. It has various applications, which include demonstration of aerodynamic loads in the building, automobile, wind energy, and aircraft industries. However, owing to the high equipment costs and space-requirements of wind tunnels, it is challenging for numerous studies to utilize a wind tunnel. Therefore, a digital wind tunnel can be utilized as an alternative for experimental research because it occupies a significantly smaller space and is easily operable. In this study, we performed airfoil testing based on velocity field measurements utilizing a digital wind tunnel. This wind tunnel can potentially be utilized to test the full-range aerodynamic characteristics of airfoils.

• The Bulletin of The Korean Astronomical Society
• /
• v.42 no.1
• /
• pp.39.4-40
• /
• 2017

According to the Korean government's Long-term Space Development Plan 2040, "Creative space science research" is included in a statement to investigate the origin and evolution of the universe by conducting a series of Korean space telescope missions: launch of space telescopes on a small satellite and an international collaboration explorer by 2020, a mid-size domestic space telescope by 2030, and a large size Korea leading international space telescope by 2040. We studied the feasibility of the future Korean Space Telescope (KST) for a mid-size domestic satellite platform. In order to pursue the uniqueness of the science program, we consider a wide range of observing wavelength (0.2um ~ 2.0um) with a spectral resolution of R~6 in the NUV and optical bands, and R~30 for NIR, utilizing an off-axis TMS(Three Mirror System) optics with a wide field of view ($2{\times}4$ degrees) which is optimized for ultra-low surface brightness sources. The main science goals of the mission include investigations of the galaxy formation, cosmic web, and the cosmic background radiation in the NUV-NIR regions. In this paper, we present the science cases and several technical challenges to be resolved along with the future milestones for the success of the KST mission.

• Journal of The Korean Astronomical Society
• /
• v.49 no.5
• /
• pp.225-232
• /
• 2016

We present an optical imaging survey of AKARI Deep Field South (ADF-S) using the Korea Microlensing Telescope Network (KMTNet), to find optical counterparts of dusty star-forming galaxies. The ADF-S is a deep far-infrared imaging survey region with AKARI covering around 12 deg², where the deep optical imaging data are not yet available. By utilizing the wide-field capability of the KMTNet telescopes (~4 deg²), we obtain optical images in B, R and I bands for three regions. The target depth of images in B, R and I bands is ~24 mag (AB) at 5σ, which enables us to detect most dusty star-forming galaxies discovered by AKARI in the ADF-S. Those optical datasets will be helpful to constrain optical spectral energy distributions as well as to identify rare types of dusty star-forming galaxies such as dust-obscured galaxy, sub-millimeter galaxy at high redshift.

• Journal of the Economic Geographical Society of Korea
• /
• v.26 no.4
• /
• pp.443-457
• /
• 2023

This study aims to provide methods and policy implications for vitalizing the regional regeneration of local small cities through utilizing idle spaces, with Hongcheon-gun as a case. Hongcheon-gun has been changed into cultural and art space since it was selected as the venue of Gangwon Triennales, and it is an example region that vitalized local areas by utilizing idle spaces on the basis of its placeness and characteristics. For the effective future utilization of idle spaces and regional regeneration, however, first, the survey of local resources is required for the systematic management and utilization of idle spaces. Second, foundations for the management and operation of idle spaces should be constructed. Third, methods for utilization should be sought in consideration of the characteristics of idle spaces and local conditions. Fourth, connected projects should be vitalized in consideration of possibilities for the regeneration and utilization of idle spaces.

• Korean Institute of Interior Design Journal
• /
• v.18 no.4
• /
• pp.21-30
• /
• 2009

This study plans to classify the art museums in accordance with their spatial organization, analyzing their peculiarities each by its type in order to present the reference required for designing an art museums. With confidence, the analyzation as well as the results of the study contents will make worthy contribution for the future art museums. For this purpose, total of 95 art museums have been selected as the objects of analyzation. First of all, their types have been categorized in accordance with the standard of scale and architectural planning. Out of them, 33 museums have been further selected in order to see how the peculiarities of their patterns are outstanding, and then a quantitative analyzation has been made on each of them to see its space structure by utilizing 'Space Syntax'. Finally, a correlation analyzation of space structure peculiarities has been conducted and the spatial organization peculiarities per type is comprehensively arranged in accordance with the architectural planning and Space Syntax in order to present a new spatial organization per space to be used for the basic planning of the art museum. The contents of this analytical study are summarized as follows: A correlation analyzation on the typological features in terms of architectural planning and on the spatial organization features in terms of the Space Syntax has presented four new types of museum spaces: (1) Radial type, (2) Arachnoid-radial type, (3) Linear type, and (4) Grid type, in the light of which the selected 95 art museums have further been analyzed in order for their features to be reclassified.

• Korean Institute of Interior Design Journal
• /
• v.23 no.3
• /
• pp.204-211
• /
• 2014

The development of digital culture has brought radical change in the fundamental concept of what workspace is defined by and has also switched the cognition of workspace originally being a place to spend time and do activities regarding tasks into space more than just that. If we take a look at the cases overseas firms have announced after the year 2000, we can find distinguishing facts different from the existing workspace composition, like creative workspace, amusement workspace, workspace for communities, etc. Thereupon, the goal of this research is to look into the domestic characteristics of workspace by investigating and analyzing case by case targeting domestic firms. This research is to first comprehend the theoretical study of workspace, the changing environment, and the characteristics of domestic workspace, going on to utilizing the information achieved above to analyze 8 appointed domestic firms as examples. Contemporary domestic workspace is defined not a place only for activities regarding work tasks but rather a place comfortable and friendly in the concept of a second residence, community node for sharing knowledge and information, mobile space for the digital nomads, and space for coincidental encountering and communication. Based on this the analyzed characteristics of contemporary domestic work places are metaphor, convergence, beyond boundary, and emergence. The characteristics mentioned above are considered elements that increase corporate profits by managing efficient smart-work and producing creative ideas. Therefore, I believe continuous research and development related to this subject is necessary.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.10
• /
• pp.6372-6378
• /
• 2014

This study examined the formal types and public space of Mies van der Rohe's office designs in Germany. The characteristics of the formal types, the relationship between public space and formal types, and the composition of public space were analyzed by hierarchy with perspective drawings and plans. The conclusions were as follows. Mies used the formal types, such as U shape and I shape in his early days. Later, he adopted the curved shape and tried to fragment the forms by combining the curved shape with an I shape. Mies designed the entry space in front of the simple formal types. The curved shape was used to create various hierarchical courtyards and rear gardens. The results suggest that Mies developed his own ideas on the formal types and public space utilizing a variety of methods.

• Korean Institute of Interior Design Journal
• /
• no.6
• /
• pp.15-20
• /
• 1995

In this paper, a strategy for utilizing the Korean tradi-tional spaces and interior design elements in inner space in order to express Korean-style interior design has been studied. Characteristics of Korean tradition was gathered from literatures in two categories; space and el-ements. Space again has been studied in detail in the area of split, continuity, hierarchy, elasticity, dynamics. And study of elements includes floor, wall, ceiling, dan-chung, lattice, laytiles on a roof, rafter, extended eaves, the line of eaves. 30 Korean restaurants were selected, analysed and compared with literature review. Based on the compari-son, a strategy for proper expression and utilization of Korean tradition is suggested. In the process of compari-son, current status of implementation and problems were found. Traditional elements are used in about 50% of Korean restaurants located in hotels, and 25% of those located in department stores. With the survey and other professional's opinions, an implementation plan is suggest-ed as follows; 1. Succession design method of tradition should use main-ly amelioration method and use copy and partly abstraction method. 2. Expression of tradition has to include all of space, ele-ments, and decoration. In space structure, Korean tra-dition space structure must be applied. 3. In order to design with feeling of Korean tradition, various different Korean elements have to be used. 4. In order to express high quality design, high-quality elements has to be used.