• Title/Summary/Keyword: piling up

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The Change of Total Weight and Food Consumption of Abalone, Haliotis discus hannai under a Vibration and Noise (소음.진동에 따른 참전복(Haliotis discus hannai)의 전중량 및 먹이섭식량 변화)

  • Jeong, Hyeong Taek;Kim, Yeong Sik;Choe, Sang Deok
    • Journal of Environmental Science International
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    • v.13 no.6
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    • pp.581-589
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    • 2004
  • This paper describes the amount of food consumption and the change of total weight of abalone under a vibration with noise that can be occurred due to piling work. This experiment was conducted in the aquarium in Yosu National University. In normal situation the juvenile stage shell's(total length is 1~1.5cm) amount of food consumption was 0.81g, the middle stage shell(total length is 3~3.5cm) was 13.61g, and the adult stage shell (Total length is 7~7.5cm) was 43.l9g per 5 organisms in 24 hours, while the experimental group was observed low numerical value compared normal groups. The abalones' food consumption and total weight in both groups, the intermittent and continuance impact with noise and vibration, was reduced during this experiment. The abalones' food consumption and total weight in the experimental groups without vibration were recorded slightly high numerical value than the experimental groups with noise and vibration. Based on this experimental data we could conjecture the noise and vibration are harmful factors to bring up a physiological stress to abalones. Especially, the vibration impact by piling works could produce a considerably unfavorable effect to the abalones than noise impact.

Conceptual Design of Single Phase 10MVA HTS Transformer (단상 10MVA 고온초전도 변압기 개념설계)

  • 석복렬;최명준
    • Progress in Superconductivity and Cryogenics
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    • v.4 no.2
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    • pp.42-46
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    • 2002
  • This research is conducted with the object of Piling up the foundation of design technologies for high temperature superconducting (HTS) power transformer which is thought to be as a powerful power transformer of next generation. In this study, not only the theoretical design of high temperature superconducting (HTS) transformer but also the arrangements of superconducting tape and the cooling method have been conducted. Moreover, electromagnetic analyses using finite element method (FEM) were conducted to confirm the efficiency of the designed transformer.

Investigations on the bearing strength of stainless steel bolted plates under in-plane tension

  • Kiymaz, G.
    • Steel and Composite Structures
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    • v.9 no.2
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    • pp.173-189
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    • 2009
  • This paper presents a study on the behavior and design of bolted stainless steel plates under in-plane tension. Using an experimentally validated finite element (FE) program strength of stainless steel bolted plates under tension is examined with an emphasis on plate bearing mode of failure. A numerical parametric study was carried out which includes examining the behavior of stainless steel plate models with various proportions, bolt locations and in two different material grades. The models were designed to fail particularly in bolt tear-out and material piling-up modes. In the numerical simulation of the models, non-linear stress-strain material behavior of stainless steel was considered by using expressions which represent the full range of strains up to the ultimate tensile strain. Using the results of the parametric study, the effect of variations in bolt positions, such as end and edge distance and bolt pitch distance on bearing resistance of stainless steel bolted plates under in-plane tension has been investigated. Finally, the results obtained are critically examined using design estimations of the currently available international design guidance.

Characteristics Improvement of Plate-Type Ozonizer using Inverse-Polarity Voltage and Accumulative Method (역극성 전압인가와 적층법을 이용한 판형오존발생기의 특성개선)

  • Lee, Sang-Geun;Park, Yong-Gwon;Lee, Dong-Uk;Jeon, Byeong-Jun;Song, Hyeon-Jik;Lee, Gwang-Sik
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.50 no.12
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    • pp.614-621
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    • 2001
  • In this Paper, the ozonizer is fabricated by piling plate-type electrodes up to minimize and reduce install space. Hereby ozone generation characteristics of piled plate-type ozonizer were investigated. Inverse-polarity voltage was generated by H.V neon transformer. And 2 H.V neon transformers were used to supply high voltage each 9 electrodes of plate-type ozonizer. According to the experiments, ozone concentration, generation and yield were proportionally increased tilth increasing the number of electrode. And the maximum increase effects of 246%, 245%, and 33% were obtained when the number of electrode were increased from 3 up to 9.

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A Case Study of PHC Pile Behavior Characteristics on Dynamic Compacted High Rock Embankment (고성토 암버력 동다짐 지반에 시공된 PHC 말뚝의 거동특성 사례연구)

  • Yu, Nam-Jae;Yun, Dong-Kyun;Bae, Kyung-Tae;Kim, Hyung-Suk;Lee, Dal-Ho;Park, Yong-Man
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.09a
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    • pp.519-526
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    • 2010
  • The construction site for $\bigcirc\bigcirc$ transformer substation was located at a mountain valley. In order to prepare the site, the valley was first filled with crushed rock debris up to 63m. Since the main concern of this project is to minimize differential settlement of the foundation of transformer facilities, dynamic compaction was performed every 7m followed by reinforcement with EMP(Ez-Mud Piling). The EMP is one of bored piling methods, in which a hole is bored by means of air percussion and maintain by injecting Ez-Mud. Then a PHC pile (Pretensioned spun High strength Concrete pile) is embedded and finalized with a hammer. In this study, bearing capacities and long term behavior of a pile installed by EMP were investigated. To achieve these objectives, a series of tests such as static and dynamic load tests were conducted. In addition, a construction quality control standard was proposed based on the test results.

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Disposition of the obsolete Personal Computers (폐PC 처리방안에 관한 고찰)

  • 이성호
    • Journal of Korea Society of Industrial Information Systems
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    • v.4 no.3
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    • pp.28-36
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    • 1999
  • Environmental problems arise from the rapidly developing personal computers and are gradually becoming a significant part of problems. Computer industry are usually viewed as relatively clean. However, discarded personal computer and related equipment which are piling up at warehouse, or going to landfills has on the negative effects of hazardous substance on health and the ecosystem are growing problems which did not trouble society a few years ago. This paper will estimate the quantity of the obsolete personal computer in 1999 and suggest the alternatives of its disposition.

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Detection of Hotspots on Multivariate Spatial Data

  • Moon, Sung-Ho
    • Journal of the Korean Data and Information Science Society
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    • v.17 no.4
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    • pp.1181-1190
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    • 2006
  • Statistical analyses for spatial data are important features for various types of fields. Spatial data are taken at specific locations or within specific regions and their relative positions are recorded. Lattice data are synoptic observation covering an entire spatial region, like cancer rates corresponding to each county in a state. Until now, the echelon analysis has been applied only to univariate spatial data. As a result, it is impossible to detect the hotspots on the multivariate spatial data In this paper, we expand the spatial data to time series structure. And then we analyze them on the time space and detect the hotspots. Echelon dendrogram has been made by piling up each multivariate spatial data to bring time spatial data. We perform the structural analysis of temporal spatial data.

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A Study on Improving the Surface Roughness of Stereolithography Parts -Using Paraffin Coating and Grinding Postprocess- (광조형물의 표면 조도 향상에 관한 연구 -파라핀 코팅과 연삭 후처리 공정 이용-)

  • 안대건;김호찬;이석희
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2001.04a
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    • pp.45-48
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    • 2001
  • SL(Stereolithogrphy) part is made by piling up thin layers which causes the stair stepping effect at the surface of SL parts. This effect causes excessive surface roughness and requires additional postprocess finishing such as abrasive basting which is detrimental to part geometry and time consuming. Hence paraffin coating and grinding postprocess is proposed to raise the surface quality of SL part. The paraffin which has suitable properties for the proposed postprocess is coated all over the part surface. By grinding the thin layer of coated on the SL part only, the surface roughness can be improved without any damage on the part. From the experimental result, It is verified as very practical for die casting with silicon rubber mold.

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Development of Post-process for Improving the Surface Roughness of Stereolithography parts - Using Wax Coating and Grinding Post-process - (RP part 표면정도 향상을 위한 후처리 공정 개발 -왁스 코팅과 연삭 후처리 공정 이용-)

  • 안대건;김호찬;최홍태;이석희
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.10a
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    • pp.659-662
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    • 2002
  • SL(Stereolithography) part is made by piling up thin layers which causes the stair stepping effect at the surface of SL parts. This effect brings about excessive surface roughness and requires additional post-process finishing such as abrasive techniques that are detrimental to part geometry and time consuming. Hence a wax coating and grinding post-process is proposed to improve the surface quality of SL part. The wax that has suitable properties for the proposed post-process is coated all over the part surface. By grinding the thin layer of coated on the SL part only, the surface roughness can be improved without any damage on the part. From the experimental results, This approach is considered to be very practical fur die casting with RT(Rapid Tooling) techniques.

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Application Strategy of Information System to Small and Medium Enterprises (중소기업의 정보화 구축전략)

  • Sin Dong-Ju;Jeong Ho-Yeon
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2004.10a
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    • pp.501-504
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    • 2004
  • Through the recent innovative development of information technology Enterprises have applied ERP(Enterprise Resource Planning)system to their company for piling up their management system efficiency. At present the range of its application has been expanded to small and medium enterprises gradually since the ERP system was mainly applied to the large companies. Usually the small and medium enterprises have lower understanding for information management system comparatively than for production system and mostly they do not prepare their own efficient information strategies for the future. In this study, as the ERP system can bring the most efficient results in case it is properly applied to the character of their company we will analyze the character of small and medium enterprises and suggest an appropriate and efficient ERP application strategy to their management system.

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