• Title/Summary/Keyword: serious loss

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Nanocomposite Cover-layer for NFR Media (Nanocomposite 이용한 NFR Media 커버층 특성연구)

  • Kim, Jin-Hong;Lee, Jun-Seok;Seo, Jeong-Kyo
    • Transactions of the Society of Information Storage Systems
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    • v.3 no.1
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    • pp.17-22
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    • 2007
  • [ $TiO_2$ ] nanoparticles are added into UV curable resin to increase the refractive index of the cover-layer which is laminated on the media for cover-layer incident NFR. High refractive index is required for the cover-layer operating for the solid immersion lens optics with high effective numerical aperture. The eyepattern could be achieved from the cover-layer coated 20 GB ROM disc in which the refractive index of the cover-layer was 1.75, but the gap servo was unstable due to the rough surface of the cover-layer. Even though the light loss due to the nanoparticles is not serious, the rough microstructure is developed by adding the nanoparticles in the organic binder material. To achieve smooth surface for the stable gap servo, some special techniques should be added, for example the solubility of the nanoparticles should be enhanced by the optimization of the surface of the nanoparticles.

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An Experimental Study on Performances of Leaf Spring Pad Air Bearing (판 스프링 패드 공기베어링 성능에 관한 실험적 연구)

  • 이희락;제양규
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.05a
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    • pp.94-99
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    • 2003
  • As the rotating speed of rotors is increased, the instability and power loss become serious problems. Gas bearings are introduced as a good solution to those problems. But in the development of gas bearings, high load capacity and high damping force to vibrations are required. In this study a new air bearing using leaf spring pad is introduced to improve load capacity and damping force. The experimental results of the leaf spring pad air bearings show high load capacity and high damping forces. And the results show that leaf spring pad air bearings can be simultaneously acted as radial and thrust bearings

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A New Approach to the High Efficiency of Hydraulic Excavator (유압식 굴삭기의 고효율 화에 관한 새로운 접근)

  • Lee, Y.B.
    • Journal of Drive and Control
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    • v.11 no.4
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    • pp.39-45
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    • 2014
  • With recent oil price increases, the fuel efficiency of hydraulic excavators has become a serious issue. Researchers have considered weight lightening by high pressurization in order to improve the efficiency of the excavator and pump controlled actuation (PCA) and to reduce pressure loss of hybrid and valves using mechanical inertia. However, high pressurization is not very effective because the excavator operates at a low speed; a hybrid is inefficient because little accumulated inertial energy is accumulated; and PCA is ineffective because control precision and responsibility are low. In this study, a method to minimize air and gas in hydraulic oil has been presented as a simple and new way to increase hydraulic efficiency.

영세 사업장의 산업재해 특성에 대한 연구

  • 김유창;이경태;권호영;이승열;김태봉
    • Proceedings of the ESK Conference
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    • 1997.10a
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    • pp.205-213
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    • 1997
  • The production activity by human is accompanied by various accidents which resulted in human and property loss. If information on these industrial accidents can be collected and analyzed for the purpose of preventing industrial accidents, we sill be able to get ride of inductrial accidents. The accidents which involved absence from work at least 4 days in small manufacturing factories were considered in this study. 84 accidents which occurred in 1996 were investigated. These accidents were analyzed in terms of employment sector, work period, cause of accident and form of acciednt. The accidents of small manufacturing factories are numerous and are often serious and worthy of greater attention than they have received. Successful strategies for accident prevention depend on effective analysis.

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Congestion Control in TCP over ATM-UBR Networks

  • Park, Woo-Chool;Park, Sang-Jun;Rhee, Byung-Ho
    • Proceedings of the IEEK Conference
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    • 2000.07a
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    • pp.88-91
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    • 2000
  • In this paper we approach the problem of congestion control for TCP traffic over ATM-UBR networks by focusing on the fact that to get best performance. We study how to efficiently support TCP traffic in the subnet ATM model, when ATM is only a single link in the whole path. We show that when UBR connection. We analyze the ATM-UBR network service using the BSD 4.3 Reno, Tahoe TCP. However we found the fact that the characteristic of fast recovery algorithm makes a serious degradation of performance in multiple cell loss drop situation. We propose new fast recovery algorithm to solve the problem.

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Development of Power Supply Device for Load Characteristic Experimentation (부하특성실험을 위한 전원공급장치 개발)

  • Lee, Jong-Pil;Ji, Pyeong-Shik;Lim, Jae-Yoon
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.54 no.2
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    • pp.101-107
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    • 2005
  • The reduced power quality due to some of disturbances on power system has great influence on the efficient and life of load for bad with serious economic loss. The response of load about disturbance needs to analysis quantitatively in detail to improve load characteristics. In this research, a power supply device is developed to supply disturbed power similar to that of power system. The developed device can output a voltage and frequency from 180[V] to 240[V], 55[Hz] to 65[Hz] respectively. The most outstanding feature of this device is a function to be performed steady and dynamic state characteristic experiment on load or appliances. Also, this device is designed to include high accuracy ouput and simple measurement.

Sex as an important biological variable in biomedical research

  • Lee, Suk Kyeong
    • BMB Reports
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    • v.51 no.4
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    • pp.167-173
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    • 2018
  • Experimental results obtained from research using only one sex are sometimes extrapolated to both sexes without thorough justification. However, this might cause enormous economic loss and unintended fatalities. Between years 1997 and 2000, the US Food and Drug Administration suspended ten prescription drugs producing severe adverse effects on the market. Eight of the ten drugs caused greater health risks in women. Serious male biases in basic, preclinical, and clinical research were the main reason for the problem. This mini-review will describe why and how funding organizations such as the European Commission, the Canadian Institutes of Health Research, and the US National Institutes of Health have tried to influence researchers to integrate sex/gender not only in clinical research, but also in basic and preclinical research. Editorial policies of prominent journals for sex-specific reporting will also be introduced, and some considerations in integrating sex as a biological variable will be pointed out. To produce precise and reproducible results applicable for both men and women, sex should be considered as an important biological variable from basic and preclinical research.

초정밀 선형 모터의 열.진동 분석

  • 임경화;이우영;설진수;김현철
    • Proceedings of the Korean Society Of Semiconductor Equipment Technology
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    • 2004.05a
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    • pp.163-168
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    • 2004
  • Linear motor can directly apply to the system needed linear mot ions without rotary mot ions. To control a high-speed and high-resolution, the development of the linear motors is recently required in the high-integrated and speed process industry. This paper presents vibration analyses as well as measurement standards of the newly developed linear motors through analyzing the vibration characteristics and thermal behaviors of the advanced products. Vibration experiments are conducted for identifying the hysteresis and vibration level during operation. They are also included in the modal test to analyze the vibration. Analytic data using Finite Element Method (FEM) are compared with the results of the modal. Loss of temperature generated the linear motor leads to a serious deformation within its parts. The thermal behaviors are very important factor in linear motor. The FEM and experiments make it possible to understand these characteristics.

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Facilitated ion transport through cellulose triacetate-based polymer inclusion membranes: A promising method for treatment of nuclear wastewater

  • Samuel P.Kusumocahyo;Toshiyuki Kanamori;Kim, io-Sumaru;Toshio Shinbo;Hideto Matsuyama;Masaaki Teramoto
    • Proceedings of the Membrane Society of Korea Conference
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    • 2004.05a
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    • pp.43-46
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    • 2004
  • The large quantity of liquid wastes from nuclear industries such as nuclear power plants would become a serious storage problem in view point of the environmental safety. The liquid wastes should be concentrated to a smallest possible volume before the storage. The use of supported liquid membranes (SLMs) for this purpose is very attractive [1,2], however loss of solvent and carrier in the surrounding solutions limits the stability of SLMs and hinders their commercial application in the industries.(omitted)

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An Experimental Study on the Physical Properties of Foamed Concrete Using Bottom Ash (바텀 애쉬를 이용한 기포콘크리트의 물리적 특성에 관한 실험적 연구)

  • Kang Ki Woong;Kang Chul;Kwag Eun goo;Shin hong cheol;Kwon Ki Joo;Kim Jin Man
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.11a
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    • pp.525-528
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    • 2004
  • The annual consumption of coal by coal-fired power plants is increasing. Also a large amount of ash is produced. The disposal of this large amount of ash makes the serious environmental problems and economical loss. Fly ash among the ash produced is used in building industries as a substitute to cement in concrete. But bottom ash is not used because of its poor properties. This study is aimed at the production of foamed concrete using bottom ash, to examine the physical properties of foamed concrete is manufactured by autoc1aving, and to exhibit the fundamental data to use it in site.

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