• Title/Summary/Keyword: Passive elements

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Passive Design Elements in the Architectural Planning of the Public Libraries - Focusing on the Comparison between Site and Building in the G-SEED Pre-certified and Non-certified library -

  • Lee, Ga-Young;Oh, Joon-Gul
    • KIEAE Journal
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    • v.15 no.6
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    • pp.27-36
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    • 2015
  • Purpose: The definition and factors of passive design being the sustainable method of building plan through the preceding research is deducted and the effect of passive design within the public library by applying the deducted factors in the case of built public libraries and further the realization plan of green library aimed to be reviewed in this research. Method: This study is to induce common elements of architecture plan for public library and passive design, and assess application level of re-classified elements of sustainable public library in order to analyze present condition of passive design applied on facilities of public library. First, related laws and planning standards of public library will be reviewed, then the definition of passive design will be considered using advanced research. Through advanced research related to planing elements and passive design for library induced from various plans for library standards, a common ground of induced passive design element will be transformed into assessment items and practices to be analyzed. Result: Libraries which are and are not preliminarily certified by G-SEED will be compared with each other in order to analyze the effects of passive design on G-SEED. Even though various passive elements such as load reduction of air conditioning and energy efficiency exist, there are no assessment tool within G-SEED. The fact that there are only standards for temporary methods such as utilization of construction material and installation of equipment highlights the challenges in quantitative evaluation.

Analysis of Sinkhole Formation over Abandoned Mine using Active-Passive-Active Finite Elements (폐광지역에서의 싱크홀 발생 규명을 위한 Active-Passive-Active 유한요소 기법 연구)

  • Deb Debasis;Shin Hee-Soon;Choi Sung O.
    • Tunnel and Underground Space
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    • v.14 no.6 s.53
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    • pp.411-422
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    • 2004
  • Sinkhole subsidence occurs over abandoned mine workings and can be detrimental to human lives, damage to properties and other surface structures. In this study, simulation of sinkhole development process is performed using special finite element procedure. Especially, creation of mine voids due to roof falls and generation of goaf from broken rocks are simulated using active-passive-active finite elements. An active or solid element can be made passive or void once the tensile failure criterion is satisfied in the specified sinkhole formation zone. Upon completion of sinkhole development process, these passive elements in again be made active to simulate goal region. Several finite element models are analyzed to evaluate the relationships between sinkhole formation with width of gallery. depth of mine, roof condition and bulking factor of roof rocks. This study demonstrates that the concept of passive elements in numerical analysis can be used effectively for analyzing sinkhole formation or roof fall phenomenon in general.

Analysis of the Passive Design Application Status for the Improvement of G-SEED (G-SEED 개선을 위한 패시브디자인 적용현황 분석)

  • Kim, Hye-Won;Tae, Choon-Seob;Kim, Jun-Tae
    • Journal of the Korean Solar Energy Society
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    • v.35 no.6
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    • pp.35-42
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    • 2015
  • The proper use of the passive and active design elements are important for the realization of green buildings. The G-SEED (Green Standard for Energy and Environmental Design) has been implemented in Korea to promote green building construction reflecting these design elements. In this paper, evaluation items of G-SEED which related to the passive design were selected. And improvement direction for the G-SEED was proposed through the analysis of the application status of the passive design elements for the G-SEED certified buildings. This results can be used for developing study on the future improvement of the assessment criteria of G-SEED.

Effects of Alloying Elements(Cr, Mo, N) on Repassivation Characteristics of Stainless Steels Studied by the Abrading Electrode Technique and A.C Impedance Spectroscopy (마멸 전극 기법과 교류 임피던스법으로 연구한 스테인리스강의 합금원소(Cr, Mo, N)가 재부동태 특성에 미치는 영향)

  • Ham Dong-Ho;Kim Suk-Won;Lee Jae-Bong
    • Journal of the Korean Electrochemical Society
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    • v.3 no.4
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    • pp.211-218
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    • 2000
  • The effects of alloying elements, Cr, Mo, and N on repassivation characteristics of stainless steels were investigated by using the abrading electrode technique and a.c impedance spectroscopy. The role of alloying elements on the stability of passive film and their repassivation characteristics were examined using alloy steels such as Fe-Cr, Fe-Cr-Mo, 304, 304LN, 316, and 316LN. The electrochemical characteristics of the passive film were investigated by in-situ d.c. and a.c. electrochemical methods. Localized corrosion resistance is believed to have much to do with the stability and repassivation characteristics of the passive film. The effects of alloying elements on the current transients and repassivation kinetics were systematically examined by using the abrading electrode technique and a.c. impedance spectroscopy. The experimental results were analyzed in order to elucidate the relationship between passive film stability, repassivation characteristics, and alloying elements.

Passive shape control of force-induced harmonic lateral vibrations for laminated piezoelastic Bernoulli-Euler beams-theory and practical relevance

  • Schoeftner, J.;Irschik, H.
    • Smart Structures and Systems
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    • v.7 no.5
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    • pp.417-432
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    • 2011
  • The present paper is devoted to vibration canceling and shape control of piezoelastic slender beams. Taking into account the presence of electric networks, an extended electromechanically coupled Bernoulli-Euler beam theory for passive piezoelectric composite structures is shortly introduced in the first part of our contribution. The second part of the paper deals with the concept of passive shape control of beams using shaped piezoelectric layers and tuned inductive networks. It is shown that an impedance matching and a shaping condition must be fulfilled in order to perfectly cancel vibrations due to an arbitrary harmonic load for a specific frequency. As a main result of the present paper, the correctness of the theory of passive shape control is demonstrated for a harmonically excited piezoelelastic cantilever by a finite element calculation based on one-dimensional Bernoulli-Euler beam elements, as well as by the commercial finite element code of ANSYS using three-dimensional solid elements. Finally, an outlook for the practical importance of the passive shape control concept is given: It is shown that harmonic vibrations of a beam with properly shaped layers according to the presented passive shape control theory, which are attached to an resistor-inductive circuit (RL-circuit), can be significantly reduced over a large frequency range compared to a beam with uniformly distributed piezoelectric layers.

Improving power conversion efficiency of the passive transponder (Passive 트랜스폰더에서의 전력변환 효율 향상을 위한 연구)

  • Kim, Kwang-Soo;Lee, Kyo-Sung;Kim, Yang-Mo
    • Proceedings of the KIEE Conference
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    • 1998.07f
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    • pp.1951-1953
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    • 1998
  • In this study, we present the power conversion system of the passive transponder which is operated at 2.4GHz. First, The passive transponder which is the power conversion system is one of the passive transponder elements is presented. And then the power conversion system is analyzed and simulated.

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Three-Phase Hybrid Shunt Filters for Power Quality Improvement

  • Bhuvaneswari, G.;G.Nair, Manjula
    • Journal of Power Electronics
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    • v.7 no.3
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    • pp.257-264
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    • 2007
  • Active power filters can be cost-effective for use in practical systems with the insertion of a few passive elements in shunt or series configuration. The resulting hybrid filters can be designed to provide dominant lower order harmonic elimination and reactive power support by the passive elements so that the burden on the active filter counterpart is reduced. In this paper, the rate reduction in the shunt active filter is estimated when it is connected in parallel with suitable passive tuned harmonic filters. The active filtering system is based on an appropriate control scheme. The simulation and the experimental results of the shunt active filter, along with the estimated value of reduction in rating, show that the hybrid shunt filtering system is quite effective in compensating for the harmonics and reactive power, in addition to being cost-effective.

A Study of Sustainable Architectural Design Elements Based on the Classification of Natural Elements (자연요소 중심으로 분류한 친환경 건축계획 요소에 관한 연구)

  • Yim, Su Hyun;Park, Hyeon Soo
    • KIEAE Journal
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    • v.10 no.5
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    • pp.3-12
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    • 2010
  • Sustainable design is getting to be controversial issue in all industries over the world particularly, in architecture as the amount of energy usage in architecture occupies 40%. Therefore, it is essential to make the standard for the sustainable design. In order to construct the sustainable design, firstly it should be considered that sustainable design elements based on natural resources to increase building energy efficiency is established and classified. The method of sustainable design divides into passive design and active design. Passive design method should be examined with active one simultaneously for more efficient usage of energy. Next, the study is followed how the sustainable design elements is adopted in buildings through the comparison of cases study of domestic and oversea. The result of case study shows similar adoption of sustainable design elements between oversea and domestic. However, the difference is shown in the building orientation and shape and the window size and position in Solar energy as well as high performance structure in Heat energy. These elements are the most significant elements in order to reduce energy load. In oversea, sustainable design is generated by architects, a client, and consultants based on the close cooperation in the beginning of early design phase before deciding building shape and envelope while in the domestic field adoption for sustainable design is conducted after deciding building shape and material. In order to design sustainable architecture more study is necessary in early stage for Zero Carbon and reducing building energy load through relation with specialists, a client and architects.

Quantitative and Qualitative Differences according to the Shoe Type for the Grand Jete Landing in Ballet

  • Yi, Kyung-Ok;Park, Hye-Rhee
    • Korean Journal of Applied Biomechanics
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    • v.21 no.1
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    • pp.25-29
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    • 2011
  • The purpose of this study was to analyze quantitative and qualitative differences according to shoe type for the grand jete landing in ballet. The subjects for this study were 9 female ballet majors with an average of 12 years of experience. Subjects jumped, performing a front split, and landed on 1 foot, a movement called the grand jete. Analysis was performed on the students' landing. Independent variables were 3 shoe types: split sole, traditional out sole, and 5-toed forefoot shoes, with bare feet as a control group. Dependent variables were vertical passive ground reaction force and qualitative elements. Passive ground reaction force variables(maximum passive peak value, number of passive peaks, passive force-time integral, and center of pressure) were measured by the Kistler 9281B Force Platform. Qualitative elements were comfort, cushioning, pain, and fit. Statistical analysis included both 1-way ANOVA and Tukey's test for follow-up. Finalized data demonstrated that the 5-toed forefoot shoe allows the forefoot to expand and the toes to individually press down upon landing, increasing foot contact with the surface. Five-toed forefoot shoes minimize passive peaks and pain, while increasing comfort, cushioning, and fit. Most ballet movements are composed of jumping, balancing, landing, and spinning. Wearing 5-toed forefoot shoes allows for a natural range of movement in each toe, to improve both technique and balance. Pain and injuries from ballet can be minimized by wearing the correct shoe type. According to this analysis, it is possible to customized ballet shoes to increase the efficiency of techniques and movements.

The Effect of Alloying Elements and Heat Treatment on the Uniform Corrosion of 440A Martensitic Stainless Steel(I) (440A 강의 균일부식에 미치는 합금원소와 열처리의 영향(I))

  • Kim, Y.C.;Kang, C.Y.;Jung, B.H.
    • Journal of Power System Engineering
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    • v.15 no.2
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    • pp.42-48
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    • 2011
  • 440A martensitic stainless steels which were modified with reduced carbon content(~0.5%) and addition of small amount of nickel, vanadium, tungsten and molybdenum were manufactured. Effects of alloying elements and tempering temperatures on the uniform corrosion in the solution of lN H2S04 were investigated through the electrochemical polarization test. When tempering temperature is constant, corrosion current density in active-passive transition point, Icorr, decreased a little with an increase of austenitizing temperature. In addition to this, when austenitizing temperature is constant, longer holding time showed a little lower Icorr and Ipass, passive current density. And when austenitized at $1050^{\circ}C$ and tempered in a range of $350{\sim}750^{\circ}C$, best anti-corrosion properties were obtained at $350^{\circ}C$ tempering temperature while worst at $450^{\circ}C$ or $550^{\circ}C$. The specimens tempered at below $450^{\circ}C$ and above $550^{\circ}C$, similar and good anti-corrosion characteristics were obtained regardless of alloying elements added, showing anti-corrosion characteristics are influenced more by tempering temperature than by alloying elements.