• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2006년도 춘계학술대회논문집
• /
• pp.153-156
• /
• 2006

The vibration isolation system is a system that attenuates the vibration transmitted from surroundings by using external energy supply like electricity and feedback and/or feedforward functions. Such a system needs stiff structure to make precise positioning without ripple within a certain bandwidth. So, a horizontal and rotary arrangement of the actuation module is suggested by using lever linkage. Modeling and kinematic formulation are completed and system identification is accomplished to tune the design variables accurately. The vibration isolation control is performed by mu-synthesis with the uncertainties in design variables. Low frequency signal enhancement circuit and saturation proof integration algorithm are devised to use seismic sensors for displacement control. This overall system shows good disturbance rejection performance.

• 대한치과의사협회지
• /
• 제22권10호통권185호
• /
• pp.865-868
• /
• 1984

Three Korean rapidly progressive periodontitis patient (R.P.P.) were examined for the isolation and identification of black-pigmented Bacteroides and Bacteroides gingivalis in the subgingival plaque. Black-pigmented Bacteroides and Bacteroides gingivalis were recovered from all three R.P. patients and the predominant isolates were Bacteroides intermedius followed by Bacteroides gingivalis. The B. gingivalis isolated from subgingival plaque of rapidly progressive periodontitis patients were Gram-negative pleomorphic rods and each produced brown to black colonies on blood agar plate supplemented with 5% rabbit 5ug/ml haemin, 0.5ug/ml of menadione and 40ug/ml of Kanamycin. The B. gingivalis isolated were fermented none of Glucose, Sucrose, Lactose, Esculin and Cellobinose and produced indole. Isolation and identification of Bacteroides gingivalis in Korean R.P. patients can be contributed to the research on the pathogenesis of Korean periodontal disease.

• 미생물학회지
• /
• 제27권4호
• /
• pp.404-414
• /
• 1989

김치발효 중 Gram 양성세균 또는 유산균의 분리와 동정을 시도하였다. 종의 다양성은 분리배지와 온도에 영양을 받았고, 다양성은 온도가 낮아질수록 감소하는 경향이었다. MRS는 세균의 분리에 KM(김치재료로 만든 자연배지)은 종의 수를 파악 하는데 각각 적합하였다. 분리균의 동정은 Bergey's manual of Systematic Bacterio]ogy (1986)를 기초로 하여 작성한 이 분농생표(dichotomous Identification scheme)에 의하여 선행하였다. 각 온도(5, 15, $25^{\circ}C$)에서 동정된 Gram 양성세균은 Leuconostoc 5종, Streptococcus 4종, Pediococcus 3종, Bacillus 2종 그리고 Ltobacillms 18종이였다. 각 온도에서 출현 빈도가 높은 종은 $25^{\circ}C$에서 LactobaIlus ptantanmz, Streptococcµs faffinolactis, Leuconostoc maιnteroid, subsp mlsentιroides 이었고, $15^{\circ}C$에서 L. mesenteroides Lactobacillus fructosus, L. maen teroid,l.I subsp. mesent,roid, 이였고, $5^{\circ}C$ 에서 Leuconostoc sp.(65.2 빈도)에 의하여 이루어졌다. 그리고 각 온도에 따른 김치발효 중 지금까지 알려진 Pediococcus cerevisiae 와 Streptococcus faecalis는 분리되지 않았다.

• 한국치위생학회지
• /
• 제1권2호
• /
• pp.193-200
• /
• 2001

An appropriate amount of samples, collected from three each paddy forest, field and riverside soil near Taegu city, was suspended in sterile water and then diluted in order to isolation of antagonistic to oral cancer. The diluted samples were inoculated on separating medium in the routing spreading method. So, seven hundred and eighteen strains were isolated on HV agar and 220 strains were on methanol medium from soil samples. So, during the screening of anti-oral cancer activity from soil, we isolated microorganisms showing powerful antagonistic activity. Among them, No. 78 strain exhibited the most strongly anti-oral cancer activity. Microbiological properties were investigated by the methods described in the Bergey's Manual of Systematic Bacteriology and experimental methods of identification of actinomycetes by Hamada et al. As a result, a methylotrophic actinomycetes strain No. 79 was estimated as Amycolatopsis sp. based on taxonomic studies.

• 생명과학회지
• /
• 제9권5호
• /
• pp.525-530
• /
• 1999

The isolation and identification of bacteria from freshwater plant root system were performed. Twenty four different strains were identified by microbiological identification system. Gram negative bacteria were isolated three times more than Gram positive ones. The ratio of rod and coccus was 11:1. The similarity above 0.5 was 37.5% from the tested samples in identification. Among these isolated bacteria, three dominant strains Pseudomonas cepacia JH10, Xanthomonas maltophilia JH12, Aeromonas salmonicida JH13 were selected to investigate biochemical properties and optimal growth conditions. These strains reached maximum growth after 24-36 hr of incubation in peptone broth, and their optimal temperature was 28$^{\circ}C$ and that of pH was between 7 and 8.

• 제어로봇시스템학회논문지
• /
• 제8권11호
• /
• pp.928-934
• /
• 2002

A natural way to cope with fault tolerant control (FTC) problems is to modify the control parameters according to an online identification of the system parameters when a fault occurs. However. due to not only difficulties Inherent to the online multivariable identification in closed-loop systems, such as modeling errors, noise or the lack of excitation signals, but also long time requirement to identify the post-fault system and implemeutation of control problems during the identification process, we propose an alternative approach based on the observer-based fault detection and isolation (FDI) and model reference adaptive control (MRAC). The proposed robust fault diagnosis method is based on a bank of observers. We also propose a model reference adaptive control with changeable reference models according to the occurred faults. Simulation results of a flight control example show the validity and applicability of the proposed algorithms.

• 한국정밀공학회지
• /
• 제27권7호
• /
• pp.13-20
• /
• 2010

Due to the recent quantum leaps forward in bio-, nano-, and information-technologies, the precisionization and miniaturization of mechanical and electrical components are in high demand. The allowable margin for vibration limits for such equipments is becoming stricter. In order to meet this demand, understandings on the characteristics of vibration isolation systems are highly required. Among the components comprising the vibration isolation system, air spring has become a focal point. In order to develop a complex defect tester for COG bonding of display panels, a vibration isolation system composed of air springs for mounting is considered in this study. The dynamic characteristics of the air spring are investigated, which is the most essential ingredient for reducing the vibration problem of the tester to the lowest level. Uncoupled dynamic parameters of the air spring are identified through MTS experiments, followed by suggestion of a model-based approach to obtain the remaining coupled dynamic parameters. Finally, the dynamic behaviors of the air spring are estimated and discussed.

• Journal of electromagnetic engineering and science
• /
• 제16권4호
• /
• pp.206-209
• /
• 2016

This letter proposes a reconfigurable directional coupler that uses a variable impedance mismatch reflector to achieve high isolation characteristics in the antenna front end. The reconfigurable coupler consists of a directional coupler and a single-pole four-throw (SP4T) switch with different load impedances as a variable load mismatch reflector. Selection of the load impedance by the reflector allows cancellation of the reflected signal due to antenna load mismatch and the leakage from the input to isolation port of the directional coupler, resulting in high isolation characteristics. The performance of the proposed architecture in separating the received (Rx) signal from the transmitted (Tx) signal in the antenna front end was verified by implementing and testing the reconfigurable coupler at 917 MHz for UHF radio-frequency identification (RFID) applications. The proposed reconfigurable directional coupler showed an improvement in the isolation characteristics of more than 20 dB at the operation frequency band.

• Bulletin of the Korean Chemical Society
• /
• 제30권1호
• /
• pp.261-263
• /
• 2009

• Earthquakes and Structures
• /
• 제4권4호
• /
• pp.397-428
• /
• 2013

This paper examines whether the "effective period" of bilinear isolation systems, as defined invariably in most current design codes, expresses in reality the period of vibration that appears in the horizontal axis of the design response spectrum. Starting with the free vibration response, the study proceeds with a comprehensive parametric analysis of the forced vibration response of a wide collection of bilinear isolation systems subjected to pulse and seismic excitations. The study employs Fourier and Wavelet analysis together with a powerful time domain identification method for linear systems known as the Prediction Error Method. When the response history of the bilinear system exhibits a coherent oscillatory trace with a narrow frequency band as in the case of free vibration or forced vibration response from most pulselike excitations, the paper shows that the "effective period" = $T_{eff}$ of the bilinear isolation system is a dependable estimate of its vibration period; nevertheless, the period associated with the second slope of the bilinear system = $T_2$ is an even better approximation regardless the value of the dimensionless strength,$Q/(K_2u_y)=1/{\alpha}-1$, of the system. As the frequency content of the excitation widens and the intensity of the acceleration response history fluctuates more randomly, the paper reveals that the computed vibration period of the systems exhibits appreciably scattering from the computed mean value. This suggests that for several earthquake excitations the mild nonlinearities of the bilinear isolation system dominate the response and the expectation of the design codes to identify a "linear" vibration period has a marginal engineering merit.