• Title/Summary/Keyword: Original Shape

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Analysis and Design of 12/14 Bearingless Switched Reluctance Motor for Self-Starting and Torque Ripple Reduction (자기기동 및 토크리플 저감을 위한 12/14 베어링리스 SRM의 설계 및 특성해석)

  • Xu, Zhenyao;Lee, Dong-Hee;An, Young-Ju;Ahn, Jin-Woo
    • Proceedings of the KIEE Conference
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    • 2015.07a
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    • pp.682-684
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    • 2015
  • A 12/14 bearingless switched reluctance motor (BLSRM) with hybrid stator poles has been proposed due to the outstanding decoupling characteristics between the torque and suspending force. However, the motor is a two-phase motor. The output torque of the motor has torque dead zone and high torque ripple. Hence, the motor cannot self-start at some rotor positions. To solve the self-starting problems and reduce the torque ripple, a stepped rotor is proposed in this paper. Then, the motor with the stepped rotor is optimally designed. In the new designed motor, the majority parameters are kept the same with those of original motor; only the torque pole arc and rotor pole shape are optimally designed. The characteristics of the redesigned motor, such as inductance, torque and suspending force, are analyzed and compared with those in the original motor. Finally, the effectiveness of the proposed method is verified by the simulation results.

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The Aesthetics of Official Uniforms, or Kwanbok, and Embroidered Patches, or Hyungbae, and their Modern Applications (관복과 흉배의 조형미와 현대적 활용 사례)

  • Kim, Kyung-Jin;Geum, Key-Sook
    • Journal of the Korean Society of Costume
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    • v.60 no.5
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    • pp.1-18
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    • 2010
  • The Aesthetics of Kwanbok and Hyungbae and their Modern Applications Starting from practical purpose, kwanbok worn by government officers were developed in original and unique fashion over long time. In particular, as hyungbae (embroidered patches for kwanbok) that had been used for kwanbok has remained in existence even today, providing inspiration for a variety of design, it is bringing attention to the aesthetic value and importance of kwanbok. Under the circumstances, this study has elicited aesthetics from kwanbok and hyungbae as follows: First, they imply the wish of long life and happiness as a symbol of favorable omen and distinguish one's status according to the shape, color, and pattern. Second, kwanbok and hyungbae reveal our ancestors' naturalistic perspective in art. Third, pleats, slits and shapes in robes reveal practical aesthetics in composition. Fourth, slits in kwanbok create the aesthetics of contrast and harmony of lining and outer cloth. Modern applications of kwanbok is of value as they represent traditions and maintain the original forms, showing the image of Korea in the 21st century. Such efforts mean that they do not only make more beautiful clothes, but also create overall philosophies in life, including personal values.

A Study on the Structural Design for Safety Improvement of the Winch Mount of an Armored Recovery Vehicle (구난장갑차 윈치 마운트의 안전율 향상을 위한 구조설계 연구)

  • Ryu, Jeong-Min;Park, Kyung-Chul;Kang, Tae-Woo
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.16 no.1
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    • pp.58-62
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    • 2017
  • In this paper, we studied the structural design for safety improvement of the winch mount of the armored recovery vehicle. From the finite element analysis using the safety factor of the original winch mount, the results determined that the safety factor was very low, namely 1.14 at $-15^{\circ}$ when towing the maximum force. For considering the usage and safety, the safety factor needs to increase to between 1.4 and 1.6. To improve the safety factor, a re-design, such as shape modification and strengthening the welded zone, was performed. After the improvement of the structural design, the safety factor of the improved mount was calculated at 1.78, an increase of about 56.1% from that of the original mount.

Design and Performance Analysis of Adaptive Pseudomedian Filter for Digital Image Enlargement (디지털 영상 확대를 위한 적응형 Pseudomedian 필터의 설계 및 성능 분석)

  • Gwak, No-Yun;Hwang, Byeong-Won
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.4
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    • pp.1305-1315
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    • 2000
  • It is known that a digital image enlargement technique can increase the size of he image but the practical enhancement of resolution is trifle because the frequency bandwidth of the original image is basically limited. To solve this problem, this paper proposes the digital image enlargement technique which interpolates the interpolation points of horizontal and vertical direction by weighting according to the direction of edge information with the component of FOI(First Order Interpolation)and output of the pseudomedian filter for image enlargement and interpolates the interpolation points of diagonal direction by selectively transposing the direction of the subwindows of the pseudomedian filter according to the distribution of neighbored pixels thereto in the extended image. According to the proposed methods, the digital image enlargement which preserves the characteristic of the pseudomedian filter capable of keeping the reconstruction of edge information and reflects the advantage of FOI can be performed. Therefore, visual artifacts could be effectively suppressed, and most characteristics and shape of the original image can be reconstructed as well.

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Experimental Study on the Vortical Flow Behind 2-D Blade with the Variation of Trailing Edge Shape (2차원 날개 끝단 형상에 따른 후류 보오텍스 유동 변화에 대한 실험 연구)

  • Paik, Bu-Geun;Kim, Ki-Sup;Moon, Il-Sung;Ahn, Jong-Woo
    • Journal of the Society of Naval Architects of Korea
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    • v.48 no.3
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    • pp.233-237
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    • 2011
  • In the present experiments, vortical structures behind the hydrofoil trailing edge are visualized and analyzed as an elementary study for propeller singing phenomena. Two sorts of hydrofoil are selected for the measurement of shedding vortices. One was KH45 hydrofoil section and the other is KH45 with the truncated trailing edge that is positioned at X/C = 0.9523(C=chord length). Assuming the Strouhal number of 0.23, the shedding frequencies of vortices are extracted by analyzing the boundary layer thickness and the flow speed. The frequency distribution of shedding vortices is obtained with the variation of angle-of-attack while the flow speed is fixed to 8m/s. The truncation of the trailing edge makes the frequency of shedding vortices about 120Hz lower than that of original trailing edge and makes the vorticity value higher than the original trailing edge.

Adaptation Experiences in South Korea of Men defecting from North Korea (북한이탈 남성주민의 남한 사회에서의 적응경험)

  • Kim, Kyoung Mi;Kim, Miyoung
    • Journal of Korean Academy of Nursing
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    • v.43 no.3
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    • pp.431-441
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    • 2013
  • Purpose: The study was done to explore meanings and essence of the experience in South Korea of men defectors from North Korea. Methods: Data were collected from March, 2011 to May, 2012, through in-depth interviews with ten men defectors. Data analysis was conducted using the process of hermeneutic phenomenological reflection. Results: Eight essential themes were extracted; 'buoyant expectation for a new life', 'feeling guilty about family left behind in North Korea', 'inability to become acclimatized due to communication difficulties', 'inability to socialize with South Koreans due to different lifestyles', 'finding strength through trustworthy acquaintances', 'continuing reconciliation with oneself while trying to assimilate into South Korean culture', 'self-realization of one's original self', and 'continuing to feel out the possibility of a future in South Korea'. Conclusion: The findings indicate that North Korean men who defect to South Korea shape their identity through three phases: forming self-image during escape from North Korea, trying to become accustomed to South Korean society, and finding their own identity by self-realization of their original self. Eventually, the whole process enables them to recover their identity, to feel a sense of belonging, and to discover possibilities for a better future.

2D Image Construction from Low Resolution Response of a New Non-invasive Measurement for Medical Application

  • Hieda, Ichiro;Nam, Ki-Chang
    • ETRI Journal
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    • v.27 no.4
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    • pp.385-393
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    • 2005
  • This paper presents an application of digital signal processing to data acquired by the radio imaging method (RIM) that was adopted to measure moisture distribution inside the human body. RIM was originally developed for the mining industry; we are applying the method to a biomedical measurement because of its simplicity, economy, and safety. When a two-dimensional image was constructed from the measured data, the method provided insufficient resolution because the wavelength of the measurement medium, a weak electromagnetic wave in a VHF band, was longer than human tissues. We built and measured a phantom, a model simulating the human body, consisting of two water tanks representing large internal organs. A digital equalizer was applied to the measured values as a weight function, and images were reconstructed that corresponded to the original shape of the two water tanks. As a result, a two-dimensional image containing two individual peaks corresponding to the original two small water tanks was constructed. The result suggests the method was applicable to biomedical measurement by the assistance of digital signal processing. This technique may be applicable to home-based medical care and other situations in which safety, simplicity, and economy are important.

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Experimental and numerical study on generation and mitigation of vortex-induced vibration of open-cross-section composite beam

  • Zhou, Zhiyong;Zhan, Qingliang;Ge, Yaojun
    • Wind and Structures
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    • v.23 no.1
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    • pp.45-57
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    • 2016
  • Open-cross-section composite beam (OCB) tends to suffer vortex-induced vibration (VIV) due to its bluff aerodynamic shape. A cable-stayed bridge equipped with typical OCB is taken as an example in this paper to conduct sectional model wind tunnel test. Vortex-induced vibration is observed and maximum vibration amplitudes are obtained. CFD approach is employed to calculate the flow field around original cross sections in service stage and construction stage, as well as sections added with three different countermeasures: splitters, slabs and wind fairings. Results show that flow separate on the upstream edge and cause vortex shedding on original section. Splitters can only smooth the flow field on the upper surface, while slabs cannot smooth flow field on the upper or lower surface too much. Thus, splitters or slabs cannot serve as valid aerodynamic means. Wind tunnel test results show that VIV can only be mitigated when wind fairings are mounted, by which the flow field above and below the bridge deck are accelerated simultaneously.

A Study on the Oil-Controlling Adapter of Power Take-Off for Armored Recovery Vehicles (구난장갑차 동력인출장치의 오일조절용 어댑터 개발)

  • Park, Kyung-Chul;Shin, Hun-Yong;Lee, Chang-Hee
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.15 no.2
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    • pp.46-50
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    • 2016
  • When rotating the clutch drum in the power take-off (PTO) gear box of an armored recovery vehicle, lots of inner oil is drained through the adapter by centrifugal force. Therefore, a lack of lubrication is caused by inner oil loss, and the bearing is damaged by overheating. This study, therefore, aims to design an oil-controlling adapter by using shape alteration to prevent oil loss. Both the original and improved adapters were tested at 1,800rpm by using an operational test machine. When applying the original adapter to the gear box, the bearing was damaged by overheating, which was caused by the lack of lubrication. When applying the improved oil-controlling adapter, on the other hand, it prevented the loss of inner oil. Applying the improved adapter is expected to prevent the overheating caused by lack of lubrication.

A Study on the Formation of a Style - Focusing on the Style of Iris Van Herpen - (스타일 형성에 관한 연구 - Iris Van Herpen의 스타일을 중심으로 -)

  • Kim, Yon-Son
    • Journal of Fashion Business
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    • v.16 no.2
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    • pp.124-137
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    • 2012
  • This study aims to identify the meaning and formation cause of a style, and the essential elements of style formation, through psychobiological research as well as an analysis of the designs of Iris Van Herpen, a fashion designer, who in just 6 years has developed into a world-renowned new designer. As a result, it has been found that the psychobiological causes to form a style stem from the action of 'long-term memory', which is consolidated by 'selective attention', 'perceptional subjectivity', the principle of the 'neuron's connection specificity and invariance', and the principle of a 'neuronal signal's unilateral flow'. With such action, Herpen could develop her own original composition techniques. The formative shapes created by such composition techniques are characterized by enumeration, superposition, and hanging. The study has also found that the essential elements for a designer to be able to form his/her own style include 'aesthetic originality' in which the designer views the property of a thing from his/her inherent perspective, and finds the uniqueness from the thing that only he/she can express, 'technical differences' that are creative and original, and 'formative specificity' that is summarized into one property through an impressive shape.