• The KIPS Transactions:PartC
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• v.10C no.4
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• pp.455-462
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• 2003

Techniques for the reduction of SRTS jitter and pointer adjustment jitter are studied. To reduce the stuffing jitter several methods have been proposed, such as bit leaking, stuff threshold modulation and sigma delta modulation. The characteristics of jitter generated in SRTS and pointer adjustment systen implementing these reduction techniques is analyzed with computer simulation. The results show that ms jitter value decreases to less than 50% as compared to a conventional pointer adjustment system. The amplitude of SRTS jitter using new techniques decreases or Increases dependent on system parameter.

• Membrane and Water Treatment
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• v.9 no.4
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• pp.245-253
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• 2018

The aim of this study is to investigate the membrane fouling in a thermophilic membrane bioreactor (TMBR) operated different sludge retention times (SRTs). For this purpose, TMBR was operated at four different SRTs (10, 30, 60 and 100 days). Specific cake resistance (${\alpha}$), cake resistance, gel resistance, total resistance, MFI (modified fouling index) and FDR (flux decrease ratio) were calculated for all SRTs. It was observed that flux in the membrane increases with rising SRT although the sludge concentrations in the TMBR increased. The steady state flux was found to be 31.78; 34.70; 39.60 and 43.70 LMH ($Liter/m^2/h$) for the SRTs of 10, 30, 60 and 100 days respectively. The concentrations of extracellular polymeric substance (EPS) and soluble microbial product (SMP) decreased with increasing SRT. The membrane fouling rate was higher at shorter SRT and the highest fouling rate appeared at an SRT of 10 d. Both the sludge cake layer and gel layer had contribution to the fouling resistance, but the gel layer resistance value was dominant in all SRTs.

• Membrane and Water Treatment
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• v.5 no.4
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• pp.281-293
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• 2014

The present work aimed to study the decolorization kinetics and characteristics of a selected azo dye under the influence of two key operational parameters including hydraulic retention time (HRT) and solid retention time (SRT). The decolorization efficiency and the two important criteria of k and normalized k (k/MLSS) were evaluated in lab-scale membrane sequencing batch reactors (MSBRs) at various HRTs of 48, 24 and 16 h (with constant SRT) and in addition, at various SRTs of infinity, 40 and 10 d (with constant HRT). According to the obtained results, both zero and first-order kinetics were properly fitted the decolorization profiles of the selected azo dye in all of the applied HRTs and SRTs. Increase of both HRT and SRT positively affected the decolorization efficiency. More MLSS concentrations corresponded to the lower HRTs and the higher SRTs resulted in higher decolorization rate constants (k). However, the effect of reducing the HRT was not compensated by increase of the MLSS concentration in order to reach higher decolorization efficiency. In addition, increase of the decolorization efficiency, as a consequence of the higher MLSS concentrations at longer SRTs, was restrained by decrease of the time-limited decolorization capability of biomass (represented by normalized k). Evaluation of both k and normalized k is suggested in order to have a more precise study on the decolorization kinetics and characteristics.

• Proceedings of the Korea Multimedia Society Conference
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• 1998.04a
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• pp.333-338
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• 1998

본 논문에서는 AAL-2/ATM 통신망 환경에서 멀티미디어 통신을 구현하기 위한 멀티미디어 동기화 기능으로 VGC 기반의 SRTS/AAL-2를 제안한다. 제안된 멀티미디어 동기화 알고리즘에서는 가변 비트율 멀티미디어 정보의 클럭 주파수 복원을 위하여 VGC(Virtual Global Clock)을 구성하고, 이를 기반으로 한 SRTS방식의 미디어 내부 동기와, MM-SSCFS(Multimedia-SSCS)/AAL-2 프로토콜을 사용한 미디어 간의 동기를 유지하는 방법을 제안하였다. 본 논문의 실험 환경으로는 Fore ATM 교환기(155 Mbps $\times$8 port)를 사용해서 소규모 B-ISDN/ATM 통신망을 구성하였고, SUN Workstatin Solaris 2.5에 접속된 Fore ATM 접속 카드 SBA-200에서 지원하는 XTI(X/Opne Transport Interface)-API를 사용하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.2
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• pp.417-426
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• 1996

The end-to-end service clock recovery is a critical issue in providing constandt bit rate service through ATM network. The Synchronous Residual Time Stamp(SRTS) algorithm is used to recovery the source clock using time stamp of transmitter. In thispaper, we propose a Differential Residual Time Stamp (DRTS) transmission mechanism to effectively deliver the timing information of source clock in SRTS algorithm. The RTS transmission method simple in its hardware. From the results of field trial of DS3 rate interactive video communication system through B-ISDN testbed, it can be identified that DRTS method is superior to the RTS method.

• The Transactions of the Korea Information Processing Society
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• v.6 no.7
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• pp.1877-1883
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• 1999

Synchronization of the clock at the ATM receiving terminal is studied. The technique analyzed here has been adapted by ITU-T as the standard for ATM timing recovery. This paper presents analysis of SRTS method itself and jitter in SRTS. The power pectrum and rms amplitude of SRTS jitter are calculated. The calculated average rms value for T1 1.544MHz source signal is 32.63ns and 0.15ns for E4 139.264MHz signal.

• Science of Emotion and Sensibility
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• v.13 no.1
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• pp.129-146
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• 2010

System response times(SRTs) are getting important while increasing the function of system. In the past, most research studied SRTs on situation of computer usage. There are lacking the research on simple domain. This study focuses on behavioral and emotional effect on situation of cell phone usage(experience 1; independent variables: degree of SRTs, dependent variables: behavioral and emotional evaluation). And this study investigates the behavioral and emotional effect in same SRTs on different situation(experience 2; independent variables: degree of SRTs, usage mode, dependent variables: behavioral and emotional evaluation, stress, mental strain). The result indicated that long SRTs increased problem solving time and negative emotion. User evaluated the system differently according to usage mode after they performed the same task. In other word, if user had a strong goal, then they felt more negative emotion and mental effort than the user don't have a strong goal. In the goal mode group, it was important there are being of delay or not. This study demonstrated that SRTs and usage mode influence user's emotion and behavior performance in same task.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.E2
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• pp.41-48
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• 2005

A novel hybrid system composed of a biotrickling filter and an activated sludge reactor was investigated under the conditions of four different SRTs (sludge retention times). The performance of the hybrid reactor was found to be directly comparable among the four different sludge ages. Discernible differences in the removal performance were observed among four different SRTs of 2, 4, 6, and 8 days. High removal efficiency was achieved by continuous circulation of activated sludge over the immobilized mixture culture, which allowed on pH control, addition of nutrients, and removal of paint VOCs (volatile organic compounds). The results also showed that the removal efficiency for a given pollutant depends on the activity of microorganisms based on the SRT. As the SRT increased gradually from 2 to 8 days, the average removal performance decreased. The highest removal rate was achieved at the SRT of 2 days at which the highest OUR (oxygen uptake rate), $6.1mg-O_2/liter-min$ was measured. Biological activity in the recycle microbes decreased to a much lower level, $3.6mg-O_2/liter-min$ at a SRT of 8 days. It is thus believed that young microorganisms were more active and more efficient for the VOCs removal of low concentrations and high flow rates. The apparent correlation of $R^2=0.996$ between the average removal efficiency and the average OUR at each SRTs suggests that VOCs degradation by young cells significantly affected the overall removal efficiency for the tested SRTs.

• Membrane and Water Treatment
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• v.9 no.1
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• pp.33-42
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• 2018

Microscopic examination of the activated sludge and morphological characterization of the flocs provides detailed information about the treatment process. The aim of this study is to investigate the morphological parameters of flocs obtained from a thermophilic jet loop membrane bioreactor (JLMBR) in different sludge retention times (SRTs), considering EPS and SMP concentration, hydrophobicity, zeta potential. The results showed that irregularity decreased with the increasing SRT. The compactness value was calculated to be less than 1 for all SRTs. However, the sludge had a more compact structure when the SRT increased. Zeta potential increased whereas hydrophobicity and floc size reduced, with increasing SRT. Furthermore, 2-D porosity calculated using the hole ratio was higher at greater SRTs. Hence, there was a significant correlation between the results obtained using the imaging technique and operation conditions of thermophilic JLMBR.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.748-754
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• 2006

Small Rapid Transit System(SRTS) will be defined fully automated urban transit system providing a rapid and personalized door to door transport service. Conventional forms of public transit require passengers to collect in groups until a large vehicle is scheduled to travel on predetermined routes. In contrast, SRTS offers personal transport with no waiting, and takes passengers non-stop to their chosen destination. This is a transport system which is as convenient as, or in congested environments more convenient than, the car, but with minimal environmental impact. Accordingly the foundation study of choice system size for development of SRTS