• 제목/요약/키워드: Abnormally

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Improvement of Vehicle Directional Stability in Cornering Based on Yaw Moment Control

  • Youn, Weon-Young;Song, Jae-Bok
    • Journal of Mechanical Science and Technology
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    • v.14 no.8
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    • pp.836-844
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    • 2000
  • In this research any abnormal motion of a vehicle is detected by utilizing the difference between the reference and actual yaw velocities as sell as the information on vehicle slip angle and slip angular velocity. This information is then used as a criterion for execution of the yaw moment control. A yaw moment control algorithm based on the brake control is proposed for improving the directional stability of the vehicle. The controller executes brake controls to provide each wheel with adequate brake pressures, which generate the needed yaw moment. It is shown that the proposed yaw moment control logic can provide excellent cornering capabilities even on low friction roads. This active control scheme can prevent a vehicle from behaving abnormally, and can assist normal drivers in coping with dangerous situations as well as experienced drivers.

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Smog and Health Effects -A Review of london Smog of December, 1952- (스모그와 건강피해 - 런던스모그참사의 재조명)

  • 조윤승
    • Journal of environmental and Sanitary engineering
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    • v.6 no.1
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    • pp.109-120
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    • 1991
  • This paper briefly reviews our knowledge concerning the potential health risk of smog. It includes a review of the meteorological phenomenon, the causes of death in different age groups from London smog which occurred during the week of December 5, 6, 7, 8, 1952. During the London disaster, which caused 4,000 excess human deaths, it was deternimed the meteorological factors of almost absence of wind, low temperature, high humidity and an inversion. Hence, at ground level of air pollutants were suddenly increased and attributed to the combined action of a particulate matter with sulfur dioxide. As a result, abnormally large numbers of persons died especially, those individuals already suffering from disease of the respiratory and cardiovascular systems.

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Chemical Composition of Archaeological Woods Submerged in the Seawater (수침고목재(水浸古木材)의 화학조성(化學組成))

  • Kim, Yoon-Soo;Bang, Joo-Wan;Kim, Ik-Joo;Choi, Kwang-Nam
    • Journal of the Korean Wood Science and Technology
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    • v.18 no.2
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    • pp.3-7
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    • 1990
  • The chemical Composition of Chinese red pine (Pinus massoniana) submerged in the Yellow Sea for more than 700 years has been examined. When compared to the recent wood, the marked chemical changes in the waterlogged wood is the higher amount of lignin with lesser amount of holocellulose and abnormally high ash content. In the heavily degraded samples, the degradation of cellulose is more severe than that of hemicellulose. However, hemicellulose is much more attacked than the cellulose at the initial stage of deterioration in the sea water. Chemical analysis suggests that the cellulolytic marine microorganisms, whether they are fungi or bacteria. can be regarded as the primary agents for the destruction of the archaeological woods submerged in the sea water.

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Studies on the Effect of 'Gal Geun Tang' upon Stress Resistance of Rats (갈근탕(葛根湯) 투여가 흰 쥐의 스트레스 저항 반응에 미치는 영향에 관한 연구)

  • Kwon, Chang-Ho
    • Korean Journal of Pharmacognosy
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    • v.5 no.4
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    • pp.217-222
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    • 1974
  • Oxygen consumption rate has been determined to study the effect of 'Gal Geun Tang' upon stress resistance of rats. The oxygen consumption rate of liver tissue increased slightly when normal rats were given the Gal Geun Tang infusion only. When rats were given the infusion after an injection of typhoid vaccine, the elevated boby temperature and oxygen consumption rate due to typhoid vaccine fell to normal level. From this result, it is concluded that 'Gal Geun Tang' has a function that may normalize abnormally strained liver metabolism. Oxygen consumption rate of the rats significantly increased when rats were exposed to cold condition. However, under the same condition it rather maintained the normal consumption rate when the rats were given previously "Gal Geun Tang". It is suggested that 'Gal Geun Tang' has an effects that impairs the immune response from cold stress. The rats that were given Cinnamomi Ramulus('Ge Ji Tang') showed less effect than the group of 'Gal Geun Tang'.

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Experimental Studies on the Antidiarrheal Effects of Anjang-san

  • Oh, Seung-Whan;Ryu, Bong-Ha
    • The Journal of Korean Medicine
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    • v.32 no.6
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    • pp.54-66
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    • 2011
  • Objectives: The purpose of the present study was to investigate the antidiarrheal effects of Anjang-san in mice and rats. Methods: We measured the content of condensed tannin in Anjang-san extract, and observed the effects of Anjang-san on the small intestinal and colonic transport of mice, as well as on mice models of diarrhea induced by castor oil and $MgSO_4$, and on rat models of castor oil-induced enteropooling. Results: Anjang-san showed significant inhibitory effects on abnormally increased small intestinal transit induced by pyridostigmine and neostigmine, and inhibitory effects on large intestinal transit. Anjang-san also exhibited antidiarrheal effects on diarrhea induced by $MgSO_4$, and inhibitory effects on castor oil-induced enteropooling. Anjang-san also improved castor oil-induced diarrhea based on simple numbers without statistical significance. Conclusion: These results demonstrate that Anjang-san has significant antidiarrheal properties and attests to its possible utility in functional diarrheas, irritable bowel syndrome and other gastrointestinal disorders based upon further studies.

Cyclooxygenase-2 as a Molecular Target for Cancer Chemopreventive Agents

  • Surh, Young-Joon
    • Toxicological Research
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    • v.17
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    • pp.89-96
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    • 2001
  • Recently, considerable attention has been focused on the role of cyclooxygenase-2 (COX-2) in the carcinogenesis as well as in inflammation. Improperly overexpressed COX-2 has been observed in many types of human cancers and transformed cells in culture. Thus, it is conceivable that targeted inhibition of abnormally or improperly up-regulated COX-2 provides one of the most effective and promising strategies for cancer prevention. A ubiquitous eukaryotic transcription factor, NF-kB is considered to be involved in regulation of COX-2 expression. Furthermore, extracellular-regulated protein kinase and p38 mitogen-activated protein (MAP) kinase appear to be key elements of the intracellular signaling cascades involved in NF-kB activation in response to a wide array of external stimuli. Certain chemopreventive phytochemicals suppress activation of NF-kB by blocking one or more of the MAP kinases, which may contribute to their inhibitory effects on COX-2 induction. One of the plausible mechanisms by which chemopreventive phytochemicals inhibit NF-kB activation involves suppression of degradation of the inhibitory unit I kB, which hampers subsequent translocation of p65, the functionally active subunit of NF-kB.

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Development of the Integral LED Package Board Power Supply Circuits for Noise Cancellation (일체형 LED Package Board의 노이즈 제거 및 간소화된 전원 공급 회로 개발)

  • Yu, Young-Jin;Park, Jong-Chan
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.60 no.2
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    • pp.72-75
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    • 2011
  • In this paper, the voltage across the LED system supplied by positive voltage of power supply system the power consumption of the LED itself, and uses a lot of transformers and analog devices, such as converter startup problems and constant temperature even when the voltage driving abnormally LED current in the destruction caused by the flow of a lot of problems can occur. In this paper, we obtain the technology of consistent current using PWM(pulse width modulation) mode in order to minimize analog devices and eventually discuss the technology to develop consistent output converter using power drive IC.

Effect of Seeding on Microstructural Development of Silicon Nitride Ceramics (질화규소 세라믹스의 미세조직 형성에 미치는 Seed 첨가의 영향)

  • 이창주
    • Journal of Powder Materials
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    • v.5 no.2
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    • pp.133-138
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    • 1998
  • The effect of $\beta$-$Si_3N_4$ seeding on microstructural development of silicon nitride based materials has been investigated. In particular, to observe more distinctly the abnormal grain growth in pressureless sintering, fine $\alpha$-$Si_3N_4$(mean particle size: 0.26 ${\mu}m$) powder classified by sedimentation method was used. It was possible to prepare silicon nitride with abnormally grown grains under low nitrogen pressure of 1 atm thanks to the heterogeneous nucleation on $Si_3N_4$ seed particles. The size and morphology of silicon nitride grains were strongly influenced by the presence of $\beta$-$Si_3N_4$ seed and overall chemical composition. For specimens with initially low $\beta$-content, the large grains grew without a significant impingement by other large grains. On the contrary, for specimens with initially high $\beta$-content, steric hindrance was effective. The resulting microstructure was less inhomogeneous and characterized by unimodal grain size distribution.

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A Study on Thermal Characteristics for Hand Carried Ultrasound System

  • Kim, Jong-Gu;Cho, Young-Jin;Kwack, Kae-Dal
    • Journal of Applied Reliability
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    • v.9 no.2
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    • pp.149-163
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    • 2009
  • This paper intends to suggest a design to reduce the thermal load of a hand-carried ultrasound (HCU) system, with the aim of increasing the product life. To design ways to reduce the heat load, the surface temperatures of key parts of an HCU system were measured as the 4 system cooling fans, which have a direct relation to the system life, were operated normally. When the derating rate of 80% was applied while the fans of the HCU system were operated abnormally, it was observed that the key image processing parts exceeded the surface temperature (TC) with consideration to derating. Since the part surface temperature did not exceed the derated level when the regulated voltage was derated from 12V to 9V, it is expected to lower the operating voltage of the fans to 9V to increase the fan and HCU system lifetime by 1.8 times.

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Autophagy in Tumorigenesis and Cancer Treatment

  • Xu, Dong-Wei;Zhang, Guan-Qing;Wang, Zong-Wei;Xu, Xiao-Yin;Liu, Tong-Xiang
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.6
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    • pp.2167-2175
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    • 2015
  • Autophagy is a self-digestion process, wrapping cytoplasmic proteins or organelles to form vesicles for degradation in lysosomes. The process plays an important role in the maintenance of intracellular homostasis. Here we overview articles on autophagy and cancer/tumors in Pubmed and found 327 articles. Autophagy exists in many tumors and is involved in cell malignant transformation and tumor cell growth. In early phases of tumorigenesis, autophagy clears the abnormally folded proteins and dysfunctional organelles such as mitochondria. Autophagy can also inhibit cell stress responses and prevent genetic damage. When a tumor develops, autophagy helps tumor cells survive nutritional deficiencies and hypoxic conditions. Studies of autophagy in the occurrence and progression of tumors should provide new therapeutic strategies for tumors.