• Title/Summary/Keyword: vertical space

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The Study on the Improvement of the Letter Sorting Station to Prevent WMSDs (집배원 근골격계 질환 예방을 위한 수구분대 개선에 관한 연구)

  • Lee, Chang-Min;O, Yeon-Ju
    • Journal of the Ergonomics Society of Korea
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    • v.23 no.4
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    • pp.35-43
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    • 2004
  • The purpose of this study is to redesign a letter sorting station and to present the optimal work-space through the ergonomic analysis of the sorting station for reducing the 'Work-Related MusculoSkeletal Disorders(WMSDs)'. We surveyed the work environment in terms of the reason causing WMSDs. According to the survey results, Deltoid on the arm, Trapezius on the shoulder and Erector Spinae on the waist are most frequent attacking parts. Accordingly, We classified sorting stations by the horizontal work-space(Level 1, Level 2, Level 3) and the vertical work space(Level 1, Level 2) based on the criteria of ergonomic optimal work-space. In addition we improved the sorting station through investigation and analysis of the work-load regard the each defined work-space. In order to analyze the effect of the horizontal and vertical work-space, subjects carried out simulated sorting tasks. Each level(Level 1, Level 2, Level3) of the horizontal work-space is significant regarding each muscles(the shoulder, arm and waist), and each level(Level 1, Level 2) of the vertical work-space is significant regarding the arm and waist, but not shoulder. Finally, we founded the difference of work-load according to the work-spaces. Then, it is necessary to improve the work-space causing the high work-load(Level 3 of the horizontal work-space). Then, this study presented the specification of a sorting station which is suitable to the korean body size, and constructed the 3D shaped model of the stations by the ergonomic analysis.

Study on Vertical Dynamics Compensation for Wobbling Effect Mitigation of Electrostatically Levitated Gyroscope

  • Lee, Jongmin;Song, Hyungmin;Sung, Sangkyung;Kim, Chang Joo;Lee, Sangwoo
    • International Journal of Aeronautical and Space Sciences
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    • v.15 no.3
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    • pp.293-301
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    • 2014
  • We present a study of vertical dynamics control of an electrostatically levitated gyro-accelerometer considering the wobbling effect and propose a tilt stabilization method with newly introduced control electrodes. Typically, a rotor in a vacuum rotates at high velocity, which may create a drift rate and lead to displacement instability due to the tilt angle of the rotor. To analyze this, first we set up a vertical dynamic equation and determined simulation results regarding displacement control. After deriving an equation for drift dynamics, we analyzed the drift rate of the rotor and the wobbling effect for displacement control quantitatively. Then, we designed new sub-electrodes for moment control that will decrease the drift amplitude of wobbling dynamics. Finally, a simulation study demonstrated that the vertical displacement control with the wobbling compensation electrodes mitigated the rotor's drift rate, showing the effectiveness of the newly proposed control electrodes.

A Development of 3-D Resolution Algorithm for Aircraft Collision Avoidance

  • Kim, Youngrae;Lee, Sangchul;Lee, Keumjin;Kang, Ja-Young
    • International Journal of Aeronautical and Space Sciences
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    • v.14 no.3
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    • pp.272-281
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    • 2013
  • Traffic Collision Avoidance System (TCAS) is designed to enhance safety in aircraft operations, by reducing the incidences of mid-air collision between aircraft. The current version of TCAS provides only vertical resolution advisory to the pilots, if an aircraft's collision with another is predicted to be imminent, while efforts to include horizontal resolution advisory have been made, as well. This paper introduces a collision resolution algorithm, which includes both vertical and horizontal avoidance maneuvers of aircraft. Also, the paper compares between the performance of the proposed algorithm and that of algorithms with only vertical or horizontal avoidance maneuver of aircraft.

A study on the Development of Vertical Air Temperature Distribution Model in Atrium (아트리움의 수직온도 분포해석 프로그램의 개발에 관한 연구)

  • Kim, Y.I.;Cho, K.H.;Kim, K.W.
    • Solar Energy
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    • v.17 no.3
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    • pp.3-11
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    • 1997
  • Recently the construction of atrium buildings has increased but along with it many problems in thermal environment have arised. since the exterior wall of glass, indoor temperature is greatly influenced by weather conditions and since the space volume is very large, the vertical air temperature is not uniform. So, in this study, a Vertical Temperature Distribution Model was developed to predict the vertical air temperature of an atrium and evaluate the effects of the design parameters on the air temperature distribution of an atrium. To consider the characteristics of the vertical air temperature distribution in an atrium, the Satosh Togari's Macroscopic Model was used basically for the calculation of the vertical air temperature distribution in large space and the solar radiation analysis model and natural ventilation analysis model in atrium. And to calculate the unsteady-state inside wall surface temperature(boundary condition), the finite difference method was used. For the verification of the developed temperature distribution program, numerical evaluation of air flow by the ${\kappa}-{\varepsilon}$ turbulence model and in-situ test was conducted in parallel. The results of this study, the developed temperature distribution program was seen to predict the thermal condition of the atrium very accurately.

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Rehabilitation of the Worn Dentition (심하게 마모된 치열의 전악 수복에 대한 임상적 고찰)

  • Kim, Yu-Lee
    • Journal of Dental Rehabilitation and Applied Science
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    • v.26 no.4
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    • pp.455-462
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    • 2010
  • Patients often seek rehabilitative treatment for severely worn dentition. The etiology of noncarious tooth wear due to attrition, abrasion, and erosion is multifactorial. To treat the worn dentition, it is important to identify and eliminate and/or control the factors that contribute to excessive wear. Many situations requiring complete mouth rehabilitation present with the challenge of a lack of restorative space. To establish a correct occlusal plane and space for prostheses, it is necessary to increase vertical dimension. This may require an increase in occlusal vertical dimension. Also clinicians should be able to choose the appropriate restorative materials to achieve excellence in natural esthetics as well as proper biomechanics and durability. This article presents a method for altering occlusal vertical dimension to restore dentitions with limited restorative space due to loss of tooth structure.

An Experimental Study on the Analyze the Pressure Difference in case of Fire in Vertical Space of High-Rise Buildings (고층건축물 수직공간의 화재 시 압력차 분석을 위한 실험적 연구)

  • Huh, Yerim;Kim, HyeWon;Jin, SeungHyeon;Kwon, YoungJin
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2020.06a
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    • pp.111-112
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    • 2020
  • As buildings in South Korea become more skyscrapers, the risk of fire is also emerging. Thus, regulations, regulations, and guidelines are being improved to prevent the spread of smoke in the event of a fire in high-rise buildings, but research on smoke flow and pressure distribution in vertical spaces is insufficient. Therefore, in this study, the temperature of each floor in the vertical space according to the size of the fire is measured through the miniature model experiment, and the pressure difference is calculated to establish the basic data for the improvement of the performance of domestic air supply facilities in the future. Thus, a scale model of one-sixth the size of the actual building was produced to measure the temperature, and the pressure difference was derived by substituting the value for the expression. The pressure difference varies depending on the size of the cause of the fire, and it is believed that the differential pressure and conditions of the building should be taken into account before calculating the supply volume for the analysis of the pressure difference according to the size of the cause of the fire in the event of fire.

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Townscape in a High-rise: Imageability and Accessibility of Vertical Malls in Hong Kong

  • Tan, Zheng
    • International Journal of High-Rise Buildings
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    • v.4 no.2
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    • pp.143-152
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    • 2015
  • The increasing integration of public space and consumerism in Hong Kong has yielded new urban forms. The emergent vertical malls in Hong Kong and other East Asian metropolises have overturned the existing vertical order of the city. This vertical order is determined by the level of accessibility, but is being challenged by widely adopted vertical circulation technology. Inspired by Fredric Jameson's and Rem Koolhaas' reflections on the cultural significance of vertical transportation, this article examines the conflict between market logic and urban design requirements in the vertical interior spaces. "Departmentalization," as the current programming formula for vertical malls, can be further optimized by critically applying urban design doctrines such as Kevin Lynch's five elements of city image. It concludes with a statement that the knowledge base of vertical urbanism should be open to a set of new terminology informed by a new technological environment.

Vertical Scale Height of the Topside Ionosphere Around the Korean Peninsula: Estimates from Ionosondes and the Swarm Constellation

  • Park, Jaeheung;Kwak, Young-Sil;Mun, Jun-Chul;Min, Kyoung-Wook
    • Journal of Astronomy and Space Sciences
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    • v.32 no.4
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    • pp.311-315
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    • 2015
  • In this study, we estimated the topside scale height of plasma density (Hm) using the Swarm constellation and ionosondes in Korea. The Hm above Korean Peninsula is generally around 50 km. Statistical distributions of the topside scale height exhibited a complex dependence upon local time and season. The results were in general agreement with those of Tulasi Ram et al. (2009), who used the same method to calculate the topside scale height in a mid-latitude region. On the contrary, our results did not fully coincide with those obtained by Liu et al. (2007), who used electron density profiles from Arecibo Incoherent Scatter Radar (ISR) between 1966 and 2002. The disagreement may result from the limitations in our approximation method and data coverage used for estimations, as well as the inherent dependence of Hm on Geographic LONgitude (GLON).

Adjunctive orthodontic therapy for prosthodontic treatment (보철치료를 위한 치아 이동)

  • Kook, Yoon-Ah
    • The Journal of the Korean dental association
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    • v.48 no.12
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    • pp.868-879
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    • 2010
  • Adjunctive orthodontic therapy may be required to create appropriate space, to address misalignment and tooth size discrepancy for better function and esthetics. The desired interproximal alveolar contour and gingival embrasure form can be developed during treatment. Various applications of temporary anchorage devices for pre-prosthetic tooth movement allowed clinicians to achieve high efficiency, shorter treatment time, and less discomfort of patient. Biomechanical considerations for the periodontal status of the affected teeth are required to successfully control the vertical and horizontal space. Hence, the interdisciplinary approaches have an essential role in maximizing the favorable treatment outcome. In particular, pivotal Clinical decisions such as whether to open or close the space should be made by consensus of the involved dentists. This article presents the orthodontic treatment approaches for prosthodontic works including mesiodistal and vertical space regaining specially for cases of unrestored teeth over an extended period of time.