• Title/Summary/Keyword: vertical size

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Factors Affecting on Organizational Commitment of Military Hospital Nursing Officers (군병원 간호장교의 조직애착에 영향을 미치는 요인)

  • Kim, Eun-Hee;Kam, Sin;Lee, Kyung-Eun;Han, Chang-Hyun;Park, Ki-Soo
    • Health Policy and Management
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    • v.11 no.4
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    • pp.109-128
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    • 2001
  • This study was conducted to investigate the factors affecting on organizational commitment of military hospital nursing officers. For the purpose of this study, the self-administerd questionnaire survey was done with 440 military hospital nursing officers during february, 2001. The major results of the study were summarized as follows: By path analysis using LISREL 7.0, variables such as met expectations, work involvement, pay, work definiteness, positive affectivity, family support, peer support, promotion opportunity, expectations before entering a military hospital had significant positive effect on Job satisfaction in order of size, however, vertical conflict and horizontal conflict had significant negative effect in order of size. Variables such as job satisfaction, met expectations, promotion opportunity, positive affectivity, pay had significant positive direct effect on organizational commitment in order of size, however, job routinization, job opportunity had significant negative direct effect in order of size. It was found that the following variables, listed m order of size, had significant total effects on organizational commitment: job satisfaction, met expectations, positive affectivity, promotion opportunity, pay, vertical conflict, job routinization, family support, work involvement, work definiteness, job opportunity. In considering above findings, the program or plan for job satisfaction promotion, met expectations, fair promotion opportunity, adequate pay, work definiteness, solving conflict, positive affectivity promotion would be implemented to increase organizational commitment of military hospital nursing officers.

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Drain Capacity of PVD Filter Considering the Field Condition (현장 토질특성을 고려한 연직배수재 필터의 성능평가)

  • Han, Sung-Su;Jeong, Kyeong-Han
    • Journal of the Korean Geosynthetics Society
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    • v.6 no.1
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    • pp.33-38
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    • 2007
  • PVD (Prefabricated Vertical drain) consists of filter and core. An effective PVD has two basic filtration functions ; first to retain soil particle ; and second, to allow water to pass from the soil into the PVD core without clogging or blinding. Clogging which reduces the permeability of the geotextile filter jacket is caused by fine particles penetrating into the geotextile filter jacket in relatively low permeability soil conditions. As clogging performance increases gradually, excess pore water flow from soil is resisted and finally consolidation delays. Current soil-geotextile filter system criteria are generally based on relationships between a representative pore size of the geotextile and particle size of the soil. In Korea, PVD geotextile filter system criteria have been applied by only testing AOS (Apparent Opening Size) of filters without evaluating the filtration and clogging performance on soil-geotexile filter systems. Therefore, the filtration tests on soil-geotexile filter systems were conducted in order to evaluate the filtration and clogging performance with 3 kinds of geotextile filters. On these tests, we have applied geotextile filter system criteria on PVD in ${\bigcirc}{\bigcirc}$ sites.

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The Fabrication of Artificial Fine Aggregates Using Stone Sludge and Spent Bleaching Clay

  • Kim, Kangduk
    • Journal of the Korean Ceramic Society
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    • v.51 no.5
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    • pp.492-497
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    • 2014
  • Artificial fine aggregates (denoted AFA) were fabricated using spent bleaching clay (denoted SBC) generated from processed vegetable oil and stone sludge (denoted SS) produced from crushed aggregate manufacturing materials for use as functional construction materials. Each raw material was crushed to particle size finer than $150{\mu}m$, and fine spherical pellets of approximately 1 ~ 4 mm in diameter were prepared by a pelletizing process. The physical properties of the AFA were measured with different types of sintering equipment. A new type of vertical furnace that sinters fine aggregates in a fluidized bed at high temperatures was designed and tested. AFA sintered in a rotary kiln at $1125^{\circ}C$ showed a bulk density of $1.5g/cm^3$ and a water absorption of 16%. AFA sintered in the vertical furnace at $1125^{\circ}C$ showed a bulk density of $1.9g/cm^3$ and water absorption of 8.5%. The bulk density of the AFA sintered in the vertical furnace showed a bulk density 27% higher and water absorption 47% lower than those of AFA sintered in the rotary kiln.

Seismic Qualification Analysis of a Vertical-Axis Wind Turbine (소형 수직축 풍력발전기의 내진검증 해석)

  • Choi, Young-Hyu;Hong, Min-Gi
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.15 no.3
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    • pp.21-27
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    • 2016
  • The static and dynamic structural integrity qualification was performed through the seismic analysis of a small-size Savonius-type vertical wind turbine at dead weight plus wind load and seismic loads. The ANSYS finite element program was used to develop the FEM model of the wind turbine and to accomplish static, modal, and dynamic frequency response analyses. The stress of the wind turbine structure for each wind load and dead weight was calculated and combined by taking the square root of the sum of the squares (SRSS) to obtain static stresses. Seismic response spectrum analysis was also carried out in the horizontal (X and Y) and vertical (Z) directions to determine the response stress distribution for the required response spectrum (RRS) at safe-shutdown earthquake with a 5% damping (SSE-5%) condition. The stress resulting from the seismic analysis in each of the three directions was combined with the SRSS to yield dynamic stresses. These static and dynamic stresses were summed by using the same SRSS. Finally, this total stress was compared with the allowable stress design, which was calculated based on the requirements of the KBC 2009, KS C IEC 61400-1, and KS C IEC 61400-2 codes.

Vertical Distribution and Feeding Ecology of the Mirror Dory Zenopsis nebulosa in the Southern Sea of Korea (우리나라 남해안에 서식하는 민달고기(Zenopsis nebulosa)의 수직분포와 식성)

  • Kim, Hye Rim;Kim, Jung Yun;Kim, Hee Yong;Choi, Gwang Ho;Choi, Jung Hwa
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.6
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    • pp.973-976
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    • 2013
  • We observed the vertical distribution and feeding ecology of the Mirror dory, Zenopsis nebulosa, in the Southern Sea of Korea from 2009 to 2013 using an otter trawl. The total length of captured individuals ranged from 11 to 48 cm. Individuals captured at greater depths were significantly larger than those from shallower sites. Fish abundance was significantly related to depth and temperature. We found that 89% of the total catch was obtained at depths between 80 and 140 meters. Prey organisms, including fish, crustaceans, and cephalopods, were found in Z. nebulosa stomachs. Fishes were the main prey items for all size groups. Cephalopods were consumed by individuals > 25 cm in length. Our findings suggested that the vertical distribution of Z. nebulosa varied with depth and temperature, and that the fish are carnivores.

A Study on the Improvement of the Rotor Shape for Improving Performance of Small Wind Turbine with Vertical Axis (수직축 소형 풍력터빈 성능 향상을 위한 로터 형상 개선에 대한 연구)

  • Kim, C.J.;Kim, J.U.;Paek, I.S.;Kim, C.J.
    • Journal of Industrial Technology
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    • v.37 no.1
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    • pp.37-40
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    • 2017
  • This study was carried out to improve the performance of a vertical-axis micro wind turbine. It is unique in that it has two identical generators on both sides of the main shaft. Also it has a C shape frame to fix the generators and the main shaft firmly and to provide a connection to a tower. Performance analysis of the wind turbine rotor was performed using Qblade, which is an analysis program for vertical axis wind turbines and freeware. Based on the analysis results, the blade airfoil, the chord length, and the rotor size were modified to improve the performance of the rotor. The modification was found to increase the performance of the wind turbine and to reach the targeted rated power.

Development of the Wheel Disc Spinning Machine (휠 디스크 스피닝 성형기 개발)

  • Kang, Jung-Sik;Kang, E-Sok;Lee, Hang-Soo
    • Journal of the Korean Society for Precision Engineering
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    • v.16 no.6
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    • pp.58-65
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    • 1999
  • The spinning machine has been developed for a bus and truck wheel disc which is manufactured by spinning process method. This machine has the mechanical structure with bed, 2-column, cross head, 2-vertical slide, 2-horizontal slide with forming roller, clamp slide and main spindle similar to large size vertical lathe. Main spindle attached the mandrel is rotated about 500rpm drived by 280kW power DC motor, and a rotating black material pressed on the mandrel with the clamp slide is spinformed by 2-forming rollers which are attached inner end of the 2-horizontal slides. The 2-vertical and 2-horizontal slides are actuated by the hydraulic cylinder which is controlled by the servo valve individially, and these servo valves are controlled by control signal of the CNC controller which is computed with position signal feedbacked from the encoder sensor. The developed machine can manufacture wheel disc of various section profile without mandrel change because section profile is easily modified using program editing in the CNC controller processor. The wheel disc manufactured by spinning process method has many advantages that the endurance is increased by 2 times and the weight is decreased by 30% compared with a conventional disc.

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Vertical Axis Tidal Turbine Design and CFD hydrodynamic Analysis (CFD를 이용한 수직축 터빈 설계 및 유동특성 분석)

  • Jo, Chulhee;Ko, Kwangoh;Lee, Junho;Rho, Yuho;Lee, Kanghee
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.11a
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    • pp.159.1-159.1
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    • 2011
  • Due to the global warming, the need to secure the alternative resources has become more important worldwide. Having very strong current on the west coast with up to 10 m tidal range, there are many suitable sites for the application of TCP(Tidal current power) in Korea. Not only from the current produced from the high tidal range, but also it can be widely applied to the offshore jetties and piers. The VAT(Vertical axis turbine) system could be very effective tidal device to extract the energies from the attacking flow to the structures. For the relatively slow current speed, the VAT system could be more effective application than HAT(Horizontal axis turbine) device. The performance of VAT can be evaluated by various parameters including number of blades, shape, sectional size, diameters and etc. The paper introduces the multi-layer vertical axis tidal current power system with savonius turbine. The turbine was designed with consideration of optimal blade numbers and the performance was simulated by CFD analysis.

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Two-Dimensional Numerical Simulation of Saltwater intrusion in Estuary with Sigma-Coordinate Transformation (연직좌표변환을 이용한 하구에서의 염수침투에 관한 2차원 수치모의)

  • Bae, Yong-Hoon;Park, Seong-Soo;Lee, Seung-Oh;Cho, Yong-Sik
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.1263-1267
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    • 2007
  • A more complete two-dimensional vertical numerical model has been developed to describe the saltwater intrusion in an estuary. The model is based on the previous studies in order to obtain a better accuracy. The non-linear terms of the governing equations are analyzed and the $\sigma$-coordinate system is employed in the vertical direction with full transformation which is recently issued in several studies because numerical errors can be generated during the coordinate transformation of the diffusion term. The advection terms of the governing equations are discretized by an upwind scheme in second-order of accuracy. By employing an explicit scheme for the longitudinal direction and an implicit scheme for the vertical direction, the numerical model is free from the restriction of temporal step size caused by a relatively small grid ratio. In previous researches, some terms induced from the transformation have been intentionally excluded since they are asked the complicate discretization of the numerical model. However, the lack of these terms introduces significant errors during the numerical simulation of scalar transport problems, such as saltwater intrusion and sediment transport in an estuary. The numerical accuracy attributable to the full transformation is verified by comparing results with a previous model in a simply sloped topography. The numerical model is applied to the Han River estuary. Very reasonable agreements for salinity intrusion are observed.

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Heat Treatment and Drying Methods of Small-Notched Bamboo for Vertical Flute (단소용 대나무재의 열처리 및 건조)

  • 변희섭;오승원;공태석;김종만
    • Journal of Korea Foresty Energy
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    • v.21 no.3
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    • pp.10-17
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    • 2002
  • This study was carried out to investigate a heat treatment condition and suitable drying schedule of bamboo material(Phyllostachys nigra var. henonis) for a vertical flute with small-notched bamboo. It is very important to prevent drying defects during its drying process. We investigated the effort of heat treatment the most suitable drying schedule for small-notched bamboo vertical flute without drying defects in this research. A direct heat treatment method and drying conditions of 3($20^{\circ}C$ 65%, $40^{\circ}C$ 40%, and dry at air condition) were applied to the Bamboo specimen that felled in several areas for a month. The result suggested that the most suitable drying schedule with the less split and the shortest time was to dry at $40^{\circ}C$, 40% condition and it was useful to direct heat-treatment because of reducing the number and size of split during drying bamboo.

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