• Title/Summary/Keyword: SAFE 선도

Search Result 445, Processing Time 0.028 seconds

Vibration Analysis for LP Turbine Blade Damage (저압터빈 블레이드 손상에 대한 진동 해석)

  • Kim, Hee-Soo;Bae, Yong-Chae;Kim, Yeon-Hwan;Lee, Hyun;Kim, Sung-Hwi
    • Proceedings of the KSME Conference
    • /
    • 2003.04a
    • /
    • pp.752-757
    • /
    • 2003
  • The steady stress, modal analysis for the damaged blade was carried out to evaluate the integrity of LP 4 blade row. As a result, 4 dangerous modes for LP blade row were found in the interference diagram and it was confirmed that the nozzle passing frequency has nothing to do with the blade failure. And then the dynamic stress are analysed for the 4 dangerous modes. There are some points far out of maximum allowable stress in the cover and tenon. Therefore the blade is not safe according to the Goodman judgement. So the manufacturer have modified the design of cover and tenon. Until now, the power plant is being operated without special problems.

  • PDF

Pharmalogical Effects and Toxicity of Licorice (감초의 효능과 독성)

  • 박영철;이선동;이인선
    • Toxicological Research
    • /
    • v.18 no.3
    • /
    • pp.301-309
    • /
    • 2002
  • Licorice has been wed in clinical medicine for thousands of years. However it is only in recent times that we have been able to employ scientific methods to prove its efficacy and to give us a better understanding of its mechanism of action. One of important mechanisms for its efficacy is related to mineralocorticoid activity increased by glycyrrhizic acid, the active ingredient in licorice. Also the main undesirable side-effects of Licorice relate to is mineralocorticoid activity resulting in a state of apparent mineralocorticoid excess (AME). These therapeutic and undesirable effects are explained by the inhibition of 11-$\beta$-hydroxysteroid dehydrogenase (11-$\beta$-HSD) activity. Recently, the reduction of serum testosterone in men by licorice was reported which would have important health implications in the context of fertility and sexual dysfunction. Here, health implication of licorice were reviewed In term of its pharmacodynamic and toxicodynamic mechanism.

Proposal of new GSM Authentication protocol (새로운 GSM의 인증프로토콜 제안)

  • Choi, Hyun;Song, Yun-Kyung;Park, Dong-Sun
    • Proceedings of the IEEK Conference
    • /
    • 2003.07a
    • /
    • pp.113-116
    • /
    • 2003
  • Mobile communication network because information through radio channel is passed, information may be eavesdropped and need information security countermeasure in communication network dimension for safe information exchange because there is possibility that is manufactured. This paper used Public Key Cryptography for protection and authentication connected with user authentication. Use public key and private key that is asymmetry encryption key to quote that is used at encryption, decryption of Public key. Encrypt IMSI and authentication message that is transmitted MS, VLR and HLR interval to public key, wish to embody transmitted authentication protocol safety.

  • PDF

Design of Lateral SCAS based on H for Tilt Rotor Aircraft (H 기반 틸트로터 항공기 횡방향 SCAS 설계)

  • Lee, Jangho;Yoo, Changsun;Walker, Daniel J.
    • Journal of Aerospace System Engineering
    • /
    • v.2 no.3
    • /
    • pp.1-6
    • /
    • 2008
  • The tilt rotor aircraft has the flight characteristics which takes off vertically like a helicopter and flies forward like an airplane. Especially, the transition process from a helicopter to an airplane mode requires not only the mixing of control inputs but also the stability and controllability augmentation system(SCAS) in order to keep the safe flight because there are compound flight dynamic characteristics of a helicopter and an airplane including non-linearity, uncertainty. This paper describes the design of SCAS in a lateral motion for the tilt rotor aircraft based on the $H_{\infty}$ control method, which was performed from mathematical model with weighting matrix based on the relationship between the $H_{\infty}$ norm and the sensitivity function. Through simulation analysis for the controller designed on the $H_{\infty}$ control theory, it was shown that this method may be applied to the control design of the tilt rotor aircraft.

  • PDF

Circulting Fluidized Bed Combustion of Refuse Derived Fuel and Steam Production (폐기물 고형연료(RDF)의 순환유동층 연소 및 증기생산)

  • Shun, Do-Won;Bae, Dal-Hee;Cho, Sung-Ho;Lee, Seung-Yong
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2007.11a
    • /
    • pp.613-616
    • /
    • 2007
  • A pilot scale circulating fluidized bed for refuse derived fuel is developed and constructed in order to demonstrate efficient and safe utilization of waste fuel. The capacity of the facility is 8 steam tons per hour with the steam quality of $450^{\circ}C$ and 38atm. The quantity and the quality of the produced steam is sufficient to produce 1MWe power capacity. The test operation proved the high combustion efficiency of 99% and up. The emissions of NOx, SOx in flue gas are below 100, 60ppm respectively with out any emission control. HCl emissions were above 400ppm at the combustor exit but reduced below 10ppm after scrubber.

  • PDF

A Study on the Test and Application of FPPC (사고파급방지장치(FPPC) 시험 및 적용 연구)

  • Kim, Young-Ju;Kim, Yong-Hak;Lee, Jae-Wook
    • Proceedings of the KIEE Conference
    • /
    • 1999.11b
    • /
    • pp.309-311
    • /
    • 1999
  • 대용량의 전원단지를 포함한 전력계통에서 기간 송전선로(Route) 고장발생시 해당 계통내 동기 탈조의 불안정 현상을 보이는 발전기들의 동기탈조를 방지하기 위한 사고파급방지장치(FPPC:Fault Propagation Preventive Controller)의 기본 구성, 알고리즘 현장시험 및 적용시 설치효과에 대해 검토하였다. 전원용량이 클수록 발전기 차단 제어 완료까지 요구되는 시간은 짧아지며, 제어 요구량 또한 증가한다. 따라서 제어완료까지의 시간을 최대한 짧게 하기 위한 시스템설계 및 오동작 발생을 방지하기 위한 Fail-safe 기능을 S/W와 H/W적으로 구성하였다.

  • PDF

Genotoxicological Safety of the Gamma-Irradiated Korean Red Ginseng In vitro (감마선 조사 홍삼의 안전성에 관한 유전독성학적 연구)

  • 조성기;육홍선;변명우
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.25 no.3
    • /
    • pp.491-496
    • /
    • 1996
  • This experiment was performed to determine the safety of the Korean red ginseng irradiated with gamma rays with respect to genotoxicity. Ethanol extracts of the 5 and 10 kGy gamma-irradiated red ginseng were examined in two short-term in vitro tests : (1) Salmonella typhimurium reversion assay(Ames test) in strain TA 98, TA 100 and TA 102 (2) Micronucleus test in cultured Chinese hamster ovary(CHO) cells. No mutagenicity was detected in the two assays with or without metabolic activation. It was suggested that the Korean red ginseng irradiated with gamma rays did not cause genotoxicity in vitro. Further tests of genotoxicity in vivo, chronic and reproductive toxicity should be carried out to determine whether it is safe to irradiate Korean red ginseng with practical doses of gamma rays.

  • PDF

Air Gap Change of a Maglev Vehicle at the Moment a Linear Induction Motor Runs (자기부상열차 고가 선로 구조특성에 따른 부상공극 응답)

  • Shin, Hyeon-Jae;Han, Hyung-Suk;Lee, Jong-Min;Rho, Kyu-Sok
    • Proceedings of the KSR Conference
    • /
    • 2009.05a
    • /
    • pp.1213-1217
    • /
    • 2009
  • The air gap between electromagnet and guiderail in an EMS-type Maglev vehicle must be maintained within an allowable deviation by controlling the voltage on the magnet. In this type of vehicle, the air gap response is strongly dependent on the structural characteristics of the elevated guideway, such as stiffness, damping and mass. For this reason, the dynamic interaction between the vehicle with electromagnets and the elevated guideway must be understood to ensure safe running. The response of the air gap to guideway characteristics such as mass, stiffness, and damping are analyzed through vehicle tests over different guideways. Through such tests, the design requirements for Maglev vehicles and elevated guideways can be established, improving levitation stability.

  • PDF

A Study on Development of Unmanned Airship for Agricultural spray (농약 살포용 무인비행선 개발에 관한 연구)

  • Kim, Keonsik;Park, Kunbum;Kim, Junghan;Lee, Sangjun;Song, Yongkyu
    • Journal of Aerospace System Engineering
    • /
    • v.4 no.1
    • /
    • pp.15-18
    • /
    • 2010
  • In the hot summer manual spray work for plants would be the hardest one among the agricultural field works. Besides the physical load the possible toxication would strongly ask a way to do the job on behalf of human. Although an aircraft with sprayer could be a good candidate, the manned airplanes do not play proper roles in our country because of field geometry. Today, unmanned helicopter as expensive as 200,000 dollars can do the job with high risk of control. Therefore safe and cheap air vehicle with sprayer, if developed, could be a great help to agriculture.

  • PDF