• Title/Summary/Keyword: adaptable spring

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Analysis on Human Musculoskeletal Structures with Application to Design of Adjustable Spring Mechanisms (인체의 근육구조에 대한 해석과 가변스프링 메커니즘 설계로의 적용)

  • 이병주;이재훈;김희국
    • Journal of Institute of Control, Robotics and Systems
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    • v.5 no.2
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    • pp.208-219
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    • 1999
  • Springs have been employed in a wide range of mechanical systems. This work deals with the concept of an adaptable spring mechanism which can arbitrarily modulate its spring characteristics. The adaptable spring is desired for enhancing performances of various mechanical systems employing springs. We demonstrate that such adaptable springs can be realized by adapting anthropomorphic musculoskeletal structures of the human upper-extremity, which possesses highly nonlinear kinematic-coupling among redundant muscles existing in its structures. This phenomenon has been explained by several human arm models. Based on the analysis results, we propose multi-degree-of-freedom spring mechanisms resembling the musculoskeletal structure of the human upper-extremity, and verifiy the applicability of these mechanisms through simulation.

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Analysis on Active spring effect in human-body having redundant actuation with application to motion frequency (여유구동을 지닌 인체의 능동스프링 현상에 대한 해석과 운동주파수 제어방식으로의 적용)

  • Yi, Byung-Ju
    • Journal of Institute of Control, Robotics and Systems
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    • v.5 no.8
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    • pp.977-989
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    • 1999
  • The purpose of this study is to analyze how the human body having more muscles than its degree-of-freedom modulates an effective stiffness using redundant actuation, and to apply this concept to the design and control of advanced machines which requires adaptable spring. To investigate the adaptable stiffness phenomenon due to redundant actuation in the human body, this paper derives a general stiffness model of the Human body. In particular, for a planar 1 DOF human arm model, a planar 2 DOF human arm model, a spherical 3 DOF shoulder model, a 4 DOF human arm model, and a 7 DOF human arm model, the required nonlinear geometry ad the number of required actuator for successful modulation of the effective stiffness are analyzed along with a load distribution method for modulation of the required stiffness of such systems. Secondly, the concept of motion frequency modulation is introduced to show the usefulness of adaptive stiffness modulation. The motion frequency modulation represents a control of stiffness and / or inertia properties of systems. To show the effectiveness of the proposed algorithm, simulations are performed for 2 DOF anthropomorphic robot.

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Modified sigmoid based model and experimental analysis of shape memory alloy spring as variable stiffness actuator

  • Sul, Bhagoji B.;Dhanalakshmi, K.
    • Smart Structures and Systems
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    • v.24 no.3
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    • pp.361-377
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    • 2019
  • The stiffness of shape memory alloy (SMA) spring while in actuation is represented by an empirical model that is derived from the logistic differential equation. This model correlates the stiffness to the alloy temperature and the functionality of SMA spring as active variable stiffness actuator (VSA) is analyzed based on factors that are the input conditions (activation current, duty cycle and excitation frequency) and operating conditions (pre-stress and mechanical connection). The model parameters are estimated by adopting the nonlinear least square method, henceforth, the model is validated experimentally. The average correlation factor of 0.95 between the model response and experimental results validates the proposed model. In furtherance, the justification is augmented from the comparison with existing stiffness models (logistic curve model and polynomial model). The important distinction from several observations regarding the comparison of the model prediction with the experimental states that it is more superior, flexible and adaptable than the existing. The nature of stiffness variation in the SMA spring is assessed also from the Dynamic Mechanical Thermal Analysis (DMTA), which as well proves the proposal. This model advances the ability to use SMA integrated mechanism for enhanced variable stiffness actuation. The investigation proves that the stiffness of SMA spring may be altered under controlled conditions.

Actual state Analysis for Residential space of Elderly Nursing Facility (노인요양시설의 거주공간에 대한 실태조사 분석)

  • Jang, Hye-Won;Kim, Dae-Hee;Hwang, Eun-Kyuong
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2008.04a
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    • pp.166-170
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    • 2008
  • The elder population is growing rapidly in Korea nowadays. Therefore, a demand for adaptable installation standard of residential space for the elderly is increasing with growth of the elder population. This study analyzed actual state by interviewing manager, surveying actual measurement and using draft of Elderly nursing facility which is for senile patients. As a result of the survey for size and facilities, facilities for elderly safety, accommodation per a person and room size per a person are below to standard. Therefore, establishing adaptable design standard is needed which is to make safe and fresh living environment for the elderly.

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Breeding of High Yielding and Easily Rootable Mulberry Cultivar ′Milsungppong′(Morus bombycis KOIDZ) (다수성이고 발근력이 강한 뽕품종 ′밀성뽕′육성)

  • 성규병;김현복;남학우;이상욱;구태원
    • Journal of Sericultural and Entomological Science
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    • v.43 no.1
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    • pp.9-15
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    • 2001
  • New Mulberry Cultivar, Milsungppong, was selected from F1 seedlings obtained by crossing the female, 4X Keomseolppong, and the male, Kaeryangppong. Local adaptability test has been carried out at five places(Suwon, Chunchun, Cheongju, Kongju and Sangju) for four years since 1992. Leaf quality was tested by silkworm rearing for two silkworm rearing seasons(spring and autumn) at Suwon in 1995. From these tests, Milsungppong was found to be superior to control cultivar, cultivar, Kaeryangppong, in productivity, rootability and shoot cold injury. The new cultivar, Milsungppong, has following agronomic characteristics as compared with Kaeryangppong, the most prevailing cultivar, Milsungppong, has following agronomic characteristics as compared with Kaeryangppong, the most prevailing cultivar in Korea It is triploid cultivar belonging to Morus bombycis KOIDZ with the leaf shape of five lobes, sprouting in spring nearly the same to the Kaeryangppong (Morus alba L.), high leaf yielding of 25% compared to Kaeryangppong (Morus alba L.) and the medium degree of cold resistance. It is adaptable to every where in Korea except the area cold injury broken out habitually. Milsungppong is recommended to rear silkworms not only in spring but also in autumn besides for young silkworms.

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A Study on the Needs of the utilization and improvement of the multi-family housing residence (다가구.다세대주택 소유자의 주거환경 개선 및 활용 요구에 관한 연구)

  • Kim, Hye-Yeun;Lee, Young-Sun;Jang, Mi-Seon;Lee, Yeun-Sook
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2008.11a
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    • pp.135-139
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    • 2008
  • Through the industrialization since 1960, Korean housing has been developed in a uniform way which is to demolish first and then construct from the scratch. In this process, detached houses and multi-family living detached houses have disappeared without being paid much attention. The detached houses with blood or non-blood related multi-family living situations are typically popular, and worthy enough to explore for professionals right and creative solutions to enhance their values. But many of the people suffered for the expenses and the absence of the idea to enhance their housing themselves. The purpose of this research is to clarify user's demands of developing an adaptable lifespan house and to try to find the solution about the expenses of self improvement. This study used a Small group workshop Panel Method. The workshop consisted of three stage, such as the awareness of their existing residence and lease status, the needs of the housing improvements and the demands of the adaptable house. This study is expected to serve as a fundamental data to promote discussion on reuse of existing residence building and to promote rental detached houses.

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A new breed of silkworm variety, Juhwangjam, for light pink cocoon

  • Kim, Seong-Wan;Park, Jong-Woo;Kim, Su Bae;Yu, Jeong Hee;Hong, Jeong Won;Kang, Sang Kug;Kim, Nam Suk;Kim, Kee Young
    • International Journal of Industrial Entomology and Biomaterials
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    • v.40 no.2
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    • pp.51-55
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    • 2020
  • A new silkworm variety, Juhwangjam, was bred for the producing of light pink colored cocoon. The Juhwangjam variety was selected and succeeded from the F1 of 2303 × BP Heehong in 2016 autumn. Hatchability (96%) and pupation percentage (97.6%) of Juhwangjam was matched to the authorization criteria for commercial silkworm variety. Laval period and other economical characters of Juhwangjam were similar to the authorized silkworm variety, Goldensilk. Cocoon yield of Juhwangjam in spring and autumn season was 20.0 and 14.3 kg, respectively. Therefore, a new silkworm variety, Juhwangjam for light pink cocoon, might be adaptable to culture in spring season rather than autumn season.

Analyses of Growth and Developmental Patterns and Subsequent Grain Yield of Selected Winter and Spring Wheat Cultivars Triticum aestivum L. em Thell (춘.추파성 소맥품종들의 생육 및 수량성분석)

  • Byung Han, Choi
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.30 no.1
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    • pp.93-100
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    • 1985
  • Five winter and five spring wheat cultivars of diverse genetic backgrounds were evaluated to examine different developmental responses in terms of stages of the life cycle and grain yield when grown under the different planting dates. Greatest difference in growth and developmental patterns of the winter and spring wheat cultivars occurred in stem elongation, booting, inflorescence emergence and anthesis. The growth stage of stem elongation was found to exhibit larger difference both among planting dates and cultivars. Winter wheat cultivars responded more than spring wheat cultivars to the different planting dates. Winter wheat 'Cho Kwang' and spring wheat 'Jugoku 81' were earlier and exhibited faster growth and development, while winter wheats 'Yamhill' and 'Hyslop' were later in growth and development, but exhibited faster grain filling and higher rate of grain filling, resulting in higher grain yields. Crosses between winter and spring wheat gene pools would result in earlier maturity and higher productivity for both winter and spring wheat cultivars. For developing early maturing wheat cultivars for multiple cropping sequences while maintaining productivity, selection for earliness trait should be started at the stem elongation stage. Furthermore, the breeding materials should be planted at several times for selection of shorter life cycle genotypes adaptable to the cropping sequences. This is due to the genotype x planting date interactions.

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A Study on the Interior Design Planning for Children Cultural Complex (어린이 복합문화공간 실내계획에 관한 연구)

  • So, Ah-Lum;Mo, Jeong-Hyun
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2009.11a
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    • pp.245-250
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    • 2009
  • A variety of change in modern society has affected a family structure. In addition birth rate is getting lower and nuclear family type is getting common, influence of children has highly increased. According to this phenomenon, needs and concern about education and culture for children increase sharply. Children cultural complex can be learning field, which helps children not only to rediscover the world by themselves but also to have various and abundant experience. The purpose of this study is going to extract a planning factor of the children cultural complex through case studies of korean and oversea project for adaptable children cultural complex. In addition, this study tries to analyze the features of the children cultural complex in korean and oversea. Consequently, The analysis result is to be introduced party room to children cultural complex, used the PVC tile and carpet tile for safety of children and variety, and executed program relevant to nature.

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Clearance Depth Control of Non-explosive Demining System (비폭파식 지뢰제거 시스템의 작업 깊이 제어)

  • Jeong, Hae-Kwan;Choi, Hyun-Do;Kim, Sang-Do;Kwak, Yoon-Keun
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.749-754
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    • 2004
  • Up to now, non-explosive demining system adaptable to a mobile robot has been developed. This system has much smaller platform and consists of non-explosive mechanism. Brief experiment indoors showed thai developed demining system can remove landmines well. But, out of doors, some problems are detected i.e. Inclination of overall system causes a suspension of rake rotation. In this research, a study on performance improvement of developed non-explosive demining system is mainly discussed. To compensate the inclination of the system, mechanical sensor composed of shaft and spring is used. This sensor gives a signal to a leadscrew motor and controls a rotating direction. From an experiment, it is confirmed that the mechanical sensor as stated is a good solution of the inclination of the system.

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