• Journal of the Korean Society of Propulsion Engineers
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• v.25 no.6
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• pp.29-35
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• 2021

Bell mouth inlet is applied in various industries due to the advantage of little pressure loss and accurate flow measurement. In this study, the configuration of the bell mouth intake is designed in a long radius shape, and a suitable grid size was selected to minimize the pressure drop and to prevent the engine damage by foreign objects at outdoor operating conditions. It was able to present a modified pressure drop coefficient equation from two data obtained from the computational simulation and experimental results for the total pressure loss by inlet screen installation.

• Journal of Wetlands Research
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• v.20 no.3
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• pp.243-248
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• 2018

This study was carried out to clarify changes in community structure of Quercus acutissima dominant stand on the south slope of Mt. Danseok-san with fixed twenty quadrates. Five field surveys were conducted from Aug. 1999 to May 2018. During the period, the density lessened to 0.20 in 2012 comparing with 0.33 in 1999. However recent field study in 2018 showed moderate rising to 0.24. In 1999, the DBH class distribution of all trees formed reverse J curve. However, the reverse J curve was torn down, forming bell curve. In 2018, the curve showed similar shape of reverse J shape on the group of young trees, forming bell shape on the group of mature trees. It reveals that DBH 13cm is on the threshold of trees competition trend where the downtrend in the trees are on uptrend. The most dominant Q. acutissima formed bell curve. The peak of the curve shows the shift to the right of the graph as it gets lower by year.In case of Q. mongolica, shows a change in the shape of a low bell as the distribution curve increases. The oak stand in this study is in the process of changing from the initial stage of the secondary forest succession to the intermediate stage. The most dominant tree is Q. acutissima, and the sub-dominant tree is Q. mongolica in present. Considering the age distribution of the two competing tree species, the succession of this stand is expected to transfer to the Q. mongolica-dominant community.

• Journal of architectural history
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• v.24 no.6
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• pp.57-66
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• 2015

As Sri Lanka Stupa had been affected by Indian stupa directly, understanding Sri Lanka Stupa is important to know about the flow of Buddhist Art History, which is showing the variation of Initial Buddhist stupa. Due to invasions and disasters, all Sri Lanka's Stupa collapsed and became random mound. After restoration works, Stupa shape changed dramatically from the Initial shape to Existing shape. Since it is hard to find out how Initial stupas were like, Sanchi Stupa needed to be an example for the comparative study as an Initial shape. Sri Lanka Stupa have Square foundation and 3 Basal rings that are supporting the Main Dome. Entrances are on all 4 sides, Railing and Torana(gate) has never found in Sri Lanka stupa. Sri Lanka stupa has been classified with the shape of Dome into 6~8 types according to "Vijayanta Potha", the Ancient Buddhist Description, and described by several researchers confusingly. With the inconvenience of using unfamiliar words and irrational gap between the Initial Sri Lanka stupa and Existing Sri Lanka stupa, proposing new classification of Sri Lanka Stupa is necessary. Existing Sri Lanka Stupa can be classified into 4 types : which is (1)Bell type, (2)Pot type, (3)Mound type, (4)Bubble type. This suggestion is for further studies to use Easier and shorter words to describe the types and make it reasonable to use, since the current classification includes 3 stupa types even there is no case for any of them. Restrict Stupa Classifications within existing Sri Lanka Stupa is needed because the current classification had been continued for hundreds of years without any adjustments. Bell type is mainly located in Anuradhapura. Pot type and Mound type is only found in limited area, and Bubble type is located in most area of Sri Lanka.

• Aerospace Engineering and Technology
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• v.3 no.2
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• pp.248-255
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• 2004

In this study, aerodynamic shape design of airfoils was performed by using RSM(response surface method) and two-dimensional Navier-Stokes solver. Numerical experiment points were determined by D-optimal method and quadratic response surfaces were constructed by using JMP. For the validations of design method, NACA 64621 airfoil was inversely designed to have aerodynamic characteristics of Bell airfoil. The design method was applied to the aerodynamic design of both smart UAV wing airfoil and low Reynolds rotor-blade airfoil for unmanned helicopter. The optimized airfoils showed improved performance with various constraint conditions.

• International Journal of Air-Conditioning and Refrigeration
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• v.17 no.2
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• pp.68-73
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• 2009

In this paper, a numerical study has been carried out to investigate the influence of volute geometries on the performance of a sirocco fan. In order to achieve an optimum volute design and explain the interactions between the different geometric configurations in the volute system, three-dimensional computational fluid dynamics and the 'design of experiment' method have been applied. Several geometric parameters, such as the volute expansion angle, the cut-off position and the bell mouth shape, are employed to improve efficiency and performance. $2^k$ factorial designs were performed to screen the most influential parameters and interactions, and showed that the cut-off position and the bell mouth shape are the most significant parameters. The optimum design was selected as a result of the response surface methodology, and effects of these parameters and their interactions were presented. From the results of computational analyses and experimental data, the performance and efficiency of the sirocco fan were successfully improved. Also, detailed effects of geometric variables of the volute system on the fan performance were discussed.

• Proceedings of the Acoustical Society of Korea Conference
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• 1998.06c
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• pp.287-290
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• 1998

성덕대왕 신종을 비롯한 한국범종의 독특한 특성으로 맥놀이 현상을 들 수 있는데, 이것은 한국범종의 독창적인 형상과 재질에서 기인한다. 본 논문에서는 종의 형상과 재질을 달리하였을 때 종소리의 특성이 어떻게 달라지는가를 확인하고, 이로부터 가장 좋은 소리를 내는 종의 조건을 찾아보고자 한다. 이를 위해 주석 함량, 형상, 두께가 다른 열다섯 개의 모형종에 대해서 고유 주파수의 변화와 맥놀이 현상을 알아보았다. 그리고 한국범종과 외국종과의 차이점을 알아보기 위해, 일본종과 중국종의 대표적인 형상을 갖는 모형종을 한국범종을 모델로 한 모형종과 비교해 보았다. 또한, 울림통을 종의 아래에 설치하여, 울림통의 크기와 울림통과 종의 아래에 설치하여, 울림통의 크기와 울림통과 종 사이의 거리에 따른 종소리의 변화도 분석하였다.

• Journal of the Korea Fashion and Costume Design Association
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• v.26 no.1
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• pp.1-16
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• 2024

This study aims to investigate the differences in blue jean styles and the visual images associated with them. To achieve this, literature reviews, case studies, and surveys were conducted. The results are as follows. 1) Based on previous studies, it was found that the design elements influencing the style of blue jeans and their visual images include waistline position, silhouette, details, decorations, and color. Additionally, differences in the preferences and visual evaluations of Korean and Chinese individuals regarding the style of blue jeans were confirmed. 2) Skinny blue jeans are typically characterized by a high waistline and a length that reaches the ankles, featuring a snug fit with stretchy fabric. Straight blue jeans, on the other hand, usually have a natural or high waistline and cover the instep, with a straight silhouette descending from the thigh to the hem. Bell-bottom blue jeans are primarily high-waisted and cover the instep with a silhouette forming a bell shape from the knee to the hem. 3) Korean and Chinese women in their 20s evaluated skinny, straight, and bell-bottom styles of blue jeans as having a 'casual' image. However, they also associated bell-bottom style blue jeans with 'unique' and 'attractive' images. Interestingly, Korean women described skinny-style blue jeans as making someone look 'youthful', while Chinese women perceived them as 'sophisticated', 'making the waist look thicker', and 'unassuming'. As for straight-style blue jeans, Korean women saw them as 'well-fitting', while Chinese women described them as 'making one appear taller', 'desirable', and 'free-spirited'.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.2
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• pp.95-100
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• 2005

Numerical simulations and experiments were conducted to analyze the design parameters for a slim room air-conditioner. These design parameters included a fan shape, a front panel, a scroll shape, a bell mouth, a distance between a fan and a heat exchanger, etc. Each design parameter was analyzed numerically and/or experimentally in terms of the flow rate and the sound pressure level, which should be the most influential factors for developing the slim room air-conditioner. The fan with a uniform height showed a better performance than that with a linearly varying height. It is recommended to use a front grill rather than a front panel according to sound pressure levels since the front panel itself is a huge resistance to the inlet flow. A redesigned scroll shape by changing the rotational direction of a fan also contributed a lot to lowering the sound pressure level. There existed a distance between a fan and a heat exchanger, where flow rates increased effectively.

• Journal of the Korean Institute of Rural Architecture
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• v.5 no.1
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• pp.42-61
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• 2003

The purpose of this study was to analyze the characteristics of wooden anglican church architecture in Chungcheong area. For this study, I have selected ten anglican churches, and have studied the characteristic through the actual survey and analysis. This study focuses on the architectural characteristics and evolution of wooden anglican church in chungcheong area, based on the actual survey and historical analysis. The results of this study is as follows:1)The shape of plan is long axis composed of the entry and altar. 2)The shape of elevation is composed of the roof form and existence and nonexistence of bell-tower. 3)The shape of section in divided into one kan and three kan way, by the existence and nonexistence of a row of columns in the interior. 4)The structure and design follows roof-framing.

• 전기의세계
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• v.29 no.10
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• pp.653-659
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• 1980

The paper describes a new technique for the shape design of a bell-type porcelain locke insulator in contaminated environment. Early studies on the contamination performance of insulators indicated the need for an improvable shape to provide adequate insulation strength at normal operating voltages. In this paper, under lightly and heavily contaminated site severity, the variation of voltage distribution to leakage path at insulator surfaces analyzed by the complex admittance matrix using finite element method. By this results, the improvement of shape of insulators could be approached to the available condition in contaminated environments. In applicating to compare a standard disc type with a fog disc type insulator, this design technique is valid.