• Title/Summary/Keyword: Frequency Response

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A Study on Isolation Performance of High Damping Rubber Bearing Through Shaking Table Test and Analysis (진동대 실험 및 해석을 통한 고감쇠 고무받침의 면진성능 연구)

  • Kim, Hu-Seung;Oh, Ju
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.5
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    • pp.601-611
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    • 2016
  • The research, development and use of seismic isolation systems have been increasing with the gradual development of structure safety assurance methods for earthquakes. The High Damping Rubber Bearing (HDRB), one type of seismic isolation system, is a Laminated Rubber Bearing using special High Damping Rubber. However, as its damping function is slightly lower than that of the Lead Rubber Bearing, a similar seismic isolation system, its utilization has not been high. However, the HDRB has a superior damping force to the Natural Rubber Bearing, which has similar materials and shapes, and the existing Lead Rubber Bearing has a maleficence problem in that it contains lead. Thus, studies on HDRBs that do not use lead have increased. In this study, a test targeting the HDRB was done to examine its various dependence properties, such as its compressive stress, frequency and repeated loading. To evaluate the HDRB's seismic performance in response to several earthquake waves, the shaking table test was performed and the results analyzed. The test used the downscaled bridge model and the HDRB was divided into seismic and non-seismic isolation. Consequently, when the HDRB was applied, the damping effect was higher in the non-seismic case. However, its responses on weak foundations, such as in Mexico City, represented increased shapes. Thus, its seismic isolator.

A Study on the Neurotransmitters Acting on the Medullospinal Tract Cells Related to the Cardiovascular Activity (심맥관계 활동과 관련있는 연수 척수로 세포에 작용하는 신경흥분전달물질에 대한 연구)

  • Seo, Dong-Man;Kim, Sang-Jeong;Lim, Won-il;Kim, Jun;Kim, Chong-Whan
    • Journal of Chest Surgery
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    • v.31 no.5
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    • pp.441-450
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    • 1998
  • The medullospinal tract cells are known to play an important role in the control of the cardiovascular activities. To clarify the modes of action of the neurotransmitters on these cells, glutamate, GABA(${\gamma}$-aminobutyric acid) and bicuculline were applicated iontophoretically into the rostral ventrolateral medulla in adult cats anesthetised with ${\alpha}$-chloralose. Followings are the results obtained : 1. The spontaneous activities of the cardiac-related neurons in rostral ventrolateral medulla (RVLM) were increased by the glutamate and decreased by the GABA. 2. Bicuculline, an antagonist of GABA, alone didn't increase the frequency of the action potentials, but could reverse the cellular response to the GABA, simultaneously applicated. 3. GABA seemed to decrease the peak as well as the basal discharge of the neurons in RVLM, but hardly changed their periodicities. 4. The cellular responses of RVLM evoked by the peripheral nerve stimulation could be inhibited by the iontophoretically released GABA. In conclusion, GABA seemed to act as an inhibitory neurotransmitter on the cardiac- related neurons in RVLM of the cats anesthetized with ${\alpha}$-chloralose. But the maintenance of the periodicities of these cells after the application of bicuculline suggested that the afferent activity of the baroreceptor didn't play a key role in the spontaneous activities of the RVLM neurons.

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Physiological and Anatomical Studies of Quinclorac Action (Quinclorac의 작용성(作用性)에 대한 연구(硏究))

  • Hong, S.Y.;Lee, I.J.;Kim, K.U.;Shin, D.H.;Lee, C.N.
    • Korean Journal of Weed Science
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    • v.13 no.1
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    • pp.62-70
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    • 1993
  • There was intraspecific variation in Echinochloa crus-galli var, crus-galli in response to quinclorac, showing that plan height and dry weight of a locally collected barnyardgrass(Chinjupi) from Chinju were 90.5 and 37.8% of the untreated control, while those of a locally collected one(Iripi) from Iri showed 19.1 and 14.4%, respectively. The normal distribution curve was obtained from frequency distribution of 89 rice cultivars as affected by the application rates of quinclorac at 30, 300, and 3,000g ai/ha. Protein patterns(SDS-PAGE) of two barnyardgrasses belonging to E, crus-galli var. crus-galli such as Iripi and Chinjupi were not affected by the quinclorac application, indicating that inhibition of enzyme and/or protein biosynthesis seems to be not the primary action target of quinclorac. Electronmicroscopic observation on the injured leaf of Iripi which is considered as a susceptible one showed prominent membrane disruption. Chuchungbyeo(rice variety) resulted in a greater inhibition of tomato growth than those from Chinjupi or Iripi, indicating a great amount of quinclorac discharged from rice root, Chinjupi which is relatively tolerant to quinclorac than Iripi, discharged more quinclorac causing a greater inhibition of tomato growth.

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Factors Affecting Users' Satisfaction with Order Communicating System (처방전달체계에 대한 사용자 만족도에 영향을 미치는 요인)

  • Kim, Chang-Yup;Ha, Bum-Man;Kang, Gil-Won;Kim, Byoung-Yik;Kim, Yong-Ik;Lee, Jin-Seok
    • Journal of Preventive Medicine and Public Health
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    • v.33 no.4
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    • pp.436-448
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    • 2000
  • Objectives : To identify the factors affecting users' satisfaction with the Order Communicating System(OCS) and to highlight the factors important for the successful establishment of OCS. Methods : A Users Satisfaction survey was sent to 4,513 people, consisting of 1,503 doctors, 2,379 nurses, 255 pharmacists and 370 administrative workers in 16 hospitals which had introduced OCS. The response rate was 63.9%. Measurement of users' satisfaction was peformed with the instrument which was used in Doll's study. Some aspects of Doll's instrument were adjusted according to the aims of this study. The classifying sections of this survey included age, job and status classification, computer experience, OCS education, duration of daily OCS use, type of order entering, number of personnel in the Hospital Information System's department, cost of OCS, problem frequency, proportion of work managed by hand, OCS type, and Hospital establishment type. Results : There was a positive correlation between satisfaction level and managerial status throughout all job classifications. Irrespective of the importance of OCS education as a factor relating to users' satisfaction, the additional work load caused by OCS lowered users' satisfaction. Different factors affected users' satisfaction according to job and status classification. The composition of factors affecting the pharmacist and administrative worker satisfaction levels was simpler than that of the doctor and nurse levels. There were no statistically significant differences between the actual computer experience duration of daily OCS use and users' satisfaction with OCS. Conclusions : There was an understandable relationship between users' attitude to OCS and factors affecting users' satisfaction. The results of this study could be used as a basis for the successful expansion of the operation of OCS. But more detailed studies on users' satisfaction and further improvements of methodologies are required for the successful establishment of OCS.

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Exposure to Dithiopyr Alters Swimming Performance Parameters in Zebrafish (Dithiopyr에 노출이 zebrafish의 유영 행동에 미치는 영향)

  • Oh, Junyoung;Park, Eun-Jin;Kang, Seongeun;Lee, Seungheon
    • Journal of Life Science
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    • v.26 no.2
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    • pp.181-189
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    • 2016
  • The aim of this study was to identify the effects of dithiopyr (DTP), a herbicide, on behavior in zebrafish. The toxicity of DTP has rarely been investigated in fish. In the present study, zebrafish were exposed to different concentrations of DTP in the range of 10-20 μM for 48 h in a test container, in order to measure the value of median lethal concentrations (LC50). Behavioral experiments were performed, including the novel tank test (NTT) and the open field test (OFT), to assess stress responses or locomotion. After exposure to the DTP solution at a sublethal concentration of 2.5–10 μM for 6 min, the behavior of the zebrafish was observed for 6 min. In the acute toxicity test, the LC50 value of DTP showed as 14.49 μM in the zebrafish. The NTT showed that the duration of immobility and the velocity were significantly increased by exposure at a concentration of 5 μM of DTP, compared with a control group (p<0.05). However, compared with the control group, DTP significantly decreased the distance moved and the frequency at the top of the tank, and significantly increased the turn angle and duration at the bottom, in a concentration-dependent manner (p<0.05). In addition, in the OFT, exposure to DTP significantly decreased the distance moved and velocity compared with the control group (p<0.05). Exposure to DTP also significantly increased the duration of immobility, the turn angle, and the meandering movement, in a concentration-dependent manner (p<0.05). Further, exposure to DTP at a low concentration elevated whole-body cortisol levels in the zebrafish. The results of this study thus suggest that DTP induces a toxic response and negative effects on behavior and the endocrine system in zebrafish.

Infestation of the Abalone, Haliotis Discus Hannai, by the Polydora under Intensive Culture Conditions in Korea (우리나라 전복 양식장의 패각 천공성 다모류 감염현황)

  • Won, Kyoung-Mi;Kim, Byeng-Hak;Jin, Young-Guk;Park, Young-Jin;Son, Maeng-Hyun;Cho, Mi-Young;Park, Myoung-Ae;Park, Min-Woo
    • Journal of fish pathology
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    • v.26 no.3
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    • pp.139-148
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    • 2013
  • The genus Polydora(Polychaeta, Spionidae) includes many species well known for their activity as borers. They often become harmful invaders by reducing the growth rate and meat yield of, or inducing the mortality of commercially important mollusck, abalone, Haiotis discus hannai. In 2012, the frequency of the Polydora was observed with 5~99% in live abalone and 5.3~70.3% in dead abalone shells of abalone sea-caged aquaculture system, Korea. There are many nacreous blister in the ventral margin and inner of the infestated abalone by abalone in response to the Polydora. A worm bored two holes in the shell and come in and out for ingestion the organic matters. They are more than 40 mm in length and had outstanding palps with black bars, disc form pygidium and 4 eyespots. This is the first record for the statue of Polydora infestation of sea-caged cultured abalone, Haliotis discus hannai in Korea.

A Scene Boundary Detection Scheme using Audio Information in MPEG System Stream (MPEG 시스템 스트림상에서 오디오 정보를 이용한 장면 경계 검출 방법)

  • Kim, Jae-Hong;Nang, Jong-Ho;Park, Soo-Yong
    • Journal of KIISE:Software and Applications
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    • v.27 no.8
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    • pp.864-876
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    • 2000
  • This paper proposes a new scene boundary detection scheme for the MPEG System stream using MPEG Audio information and proves its usefulness by extensive experiments. A scene boundary has a characteristic that the audio as well as video information are changed rapidly. This paper first classifies this scene boundary into three cases ; Radical, Gradual, Micro Changes, with respect to the audio changes. The Radical change has a large-scale changing of decibel value and pitch value at a scene boundary, the Gradual change shows the long-time transition of decibel and pitch values from max to min or vice versa, and the Micro change displays a some change of pitch or frequency distribution without decibel changes. Upon this analysis, a new scene change detection algorithm detecting these three cases is proposed in which a progressive window with a time line is used to trace the changes in the audio information. Some experiments with various movies show that proposed algorithm could produce a high detection ratio for Radical change that is the most popular scene change in the movies, while producing a moderate detection ratio for Gradual and Micro changes. The proposed scene boundary detection scheme could be used to build a database for visual information like MPEG System stream.

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Evaluation of the Postoperative Motor Function for Metastatic Brain Tumors Around the Motor Cortex (운동중추 주변에 위치한 전이성 뇌종양의 수술 후 운동 기능에 대한 평가)

  • Kim, Sang Hyo;Jung, Shin;Kang, Sam Suk;Lee, Jung Kil;Kim, Tae Sun;Kim, Jae Hyoo;Kim, Soo Han;Lee, Je Hyuk
    • Journal of Korean Neurosurgical Society
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    • v.30 no.sup1
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    • pp.25-29
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    • 2001
  • Objective : Intracranial metastasis is responsible for nearly 50% of mortalities of systemic cancers. Although its frequency is increasing and there is little doubt that improving the quality and expectancy of life is the final goal, the mode of treatment is still disputed. The authors report the postoperative motor function after surgery in patients with metastatic tumors around the motor cortex. Materials and Methods : We studied 24 patients with metastatic tumors around the central sulcus during the last 22 months. Motor function was assessed pre- and post-operatively as well as its response to corticosteroids. MRI, neuronavigation system and intraoperative ultrasonography were used for tumor localization and functional MRI and cortical stimulator were used to define the motor cortex. Results : Single metastasis was found in 13 cases(54%) and 11 cases(44%) had multiple foci. Thirteen cases were located in precentral, 7 in postcentral, and 4 in superior or middle-frontal lobe. The most common primary focus was the lung(16 cases). There was no difference in postoperative motor function improvement between the steroid responsive group and non-responsive group(92% versus 90%). Ninty-two percent of the patients showed significant improvement of motor function and lived independently but there was worsening in the upper extremity in one and in another no improvement. Whole brain radiation of 3000cGy was given in all cases and 4 patients died of recurrence in primary or intracranial focus during mean follow-up periods of 14 monthes. Conclusion : Surgery may provide substantial improvement of the motor function and quality of life of the patients with metastatic tumors around the motor cortex.

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The Factors Related to Intractability in Patients with Partial Epilepsy (부분성 간질환자에서 난치성에 관여하는 인자)

  • Lee, Yeung-Ki;Byun, Yeung-Ju;Park, Mee-Yeong;Hah, Jung-Sang;Lee, Se-Jin
    • Journal of Yeungnam Medical Science
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    • v.12 no.2
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    • pp.306-318
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    • 1995
  • To evaluate the intractability of partial epileptic patients by variables, the author studied 113 patients (uncontrolled: 45, controlled: 68) who were admitted to the Department of Neurology, College of Medicine, Yeungnam University from January, 1991 to August, 1993. The results were as follows. The items related to complex partial seizures, multiple seizure types and a histories of status epilepticus or clusters of seizures were significantly associated with drug-refractoriness (p<0.01). A high frequency of seizures before evaluation was associated with a poor outcome(p<0.01). The presences of known etiology of seizures, neurologic abnormalities and psychiatric disturbance were associated with limited treatment responses(p<0.01, p<0.05, p<0.01). An abnormal EEG findings such as background slowing, focal slowing, epileptiform discharges or secondarily bilateral synchrony were statistically significant (p<0.01). Age at onset, sex, distribution of epileptic foci, duration of seizure before evaluation, family history and abnormal neuroradiologic findings were not statistically significant. By these results, it was suggested that having at least four factors of the above variables were associated with limited treatment response.

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Installation of Very Broadband Seismic Stations to Observe Seismic and Cryogenic Signals, Antarctica (남극 지진 및 빙권 신호 관측을 위한 초광대역 지진계 설치)

  • Lee, Won-Sang;Park, Yong-Cheol;Yun, Suk-Young;Seo, Ki-Weon;Yee, Tae-Gyu;Choe, Han-Jin;Yoon, Ho-Il;Chae, Nam-Yi
    • Geophysics and Geophysical Exploration
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    • v.15 no.3
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    • pp.144-149
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    • 2012
  • Korea Polar Research Institute (KOPRI) has successfully installed two autonomous very broadband three-component seismic stations at the King George Island (KGI), Antarctica, during the 24th KOPRI Antarctic Summer Expedition (2010 ~ 2011). The seismic observation system is originally designed by the Incorporated Research Institutions for Seismology Program for Array Seismic Studies of the Continental Lithosphere Instrument Center, which is fully compatible with the Polar Earth Observing Network seismic system. The installation is to achieve the following major goals: 1. Monitoring local earthquakes and icequakes in and around the KGI, 2. Validating the robustness of seismic system operation under harsh environment. For further intensive studies, we plan to move and install them adding a couple more stations at ice shelf system, e.g., Larsen Ice Shelf System, Antarctica, in 2013 to figure out ice dynamics and physical interaction between lithosphere and cryosphere. In this article, we evaluate seismic station performance and characteristics by examining ambient noise, and provide operational system information such as frequency response and State-Of-Health information.