• Title/Summary/Keyword: Q&A System

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Endogenous Phenoloxidase Purified from an Earthworm, Lumbricus rubellus (붉은 지렁이(Lumbricus rubellus) 체내로부터 정제한 Phenoloxidase)

  • 백승렬;조은정;유경희;김유삼;서정진;장정순
    • The Korean Journal of Zoology
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    • v.39 no.1
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    • pp.36-46
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    • 1996
  • An endogenous phenoloxidase (EPO) from earthworm, Lumbricus rubellus, has been purified and characterized. The purified EPO using ammonium sulfate fractionation, Blue-2, Phenyl-, and Q-sepharose chromatography steps was revealed in SDS-PAGE as a single protein banri with Mr. of 59 kl)a. A native strudure of the enzyme was examined with an in situ staining of a nondenatudng-PAGE using DL-dopa as a substrate. The result showed that a single band due to the EPO activity was located siighdy above a standard polypeptide with Mr. of 210 kl)a. These fads indicate that the EPO is an oligomeric enzyme. The presence of a monophenolase activity of the purified EPO, which hydroxylates tyrosine to dopa, was confirmed by observing dopachrome accumulation at 475 nm at PH 8.0 with a typical lag phase during 60 mm. of meausrement. A series of inhibition study has been performed for the enzyme with several divalent cation chelators such as phenyithiourea (Flu), 1, lO-phenanthroline, EDTA, and EGTA. Among them, only V'flj inhibited the enzyme with 1C0.5 of 65 MM, which indicated that copper was critical for the catalysis of EPO. The enzyme was maximally active at 35'C and pH 8.0 when L-dopa to dopachrome conversion was spectrophotometricaily monitored at 475 nm. The apparent Km values of P0 for L-opa were obtained as 1.86 mM and 13.8 mM at pH 6.5 and 8.0, respectively. The catalytic efficiencies at both pH were almost identical [(kat/Km)pH8.0/(kcat/Km)pH6.5 = O.92] while the Vmax at p11 8.0 was 6.6-fold higher than that at pH 6.5. This fact may indicate that pH affeds the catalysis at substrate and/or enzyme-substrate complex level rather than the enzyme itself. Taken together, the EPO was an oligomeric enzyme which did not require proteolysis for its activation. These results also indicated that the enzyme can exist, at least, in part as a latent form In vivo, which might be distinct from the prophenoloxidase activating system. Therefore, it is pertinent to consider that there must be certain regulatory molecules or phenomena in L. rubellus which make the 1,0 in a latent form in vivo before the foreign invasions.

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Determination of Interception Flow by Pollution Load Budget Analysis in Combined Sewer Watershed (II) - Establishment of Intercepting Capacity and Reduction Goal of Overflow Pollution Load - (오염부하 물질수지 분석을 통한 합류식 하수관거 적정 차집용량 결정(II) - 차집용량과 월류오염부하 삭감목표 설정 -)

  • Lee, Doojin;Shin, EungBai
    • Journal of Korean Society of Water and Wastewater
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    • v.19 no.5
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    • pp.557-564
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    • 2005
  • The objective of this study is to evaluate a criteria of intercepting capacity and a reduction goal of overflow pollution load in combined sewer system. In the current criteria of intercepting capacity in the domestic sewage facility standard, it is known that three times of peak sewage (Q) in dry period or runoff flow by 2mm/hr is not appropriate since the intercepted flow is estimated by runoff and show different result even in the same watershed. Though a reduction goal of overflow pollution load can be determined from 1) same level of storm-water runoff pollution load in separated storm sewer, 2) less than 5% sewage load in dry weather period, by the domestic sewage facility standard, the simulated results from storm-water model show large differences between two criteria. While it is predicted that sewage pollution load standard three time larger than separated storm sewer standard in high population density and urbanized area, it is shown that separate storm sewer standard larger than sewage pollution load standard in middle population density and developing area. Accordingly, it is proposed that more reasonable intercepting flow and reduction goal of overflows pollution load should be established to minimize discharging pollution load in combined sewer systems. For the purpose, a resonable standard has to be amended by pollution load balance considering the characteristics of a watershed for generation, collection, treatment, and discharging flow.

An Adaptive Proximity Route Selection Method in DHT-Based Peer-to-Peer Systems (DHT 기반 피어-투-피어 시스템을 위한 적응적 근접경로 선택기법)

  • Song Ji-Young;Han Sae-Young;Park Sung-Yong
    • The KIPS Transactions:PartA
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    • v.13A no.1 s.98
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    • pp.11-18
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    • 2006
  • In the Internet of various networks, it is difficult to reduce real routing time by just minimizing their hop count. We propose an adaptive proximity route selection method in DHT-based peer-to-peer systems, in which nodes select the nぉe with smallest lookup latency among their routing table entries as a next routing node. Using Q-Routing algorithm and exponential recency-weighted average, each node estimates the total latency and establishes a lookup table. Moreover, without additional overhead, nodes exchange their lookup tables to update their routing tables. Several simulations measuring the lookup latencies and hop-to-hop latency show that our method outperforms the original Chord method as well as CFS' server selection method.

Purification and Characterization of 2,4-Dichlorophenol Oxidizing Peroxidase from Streptomyces sp. AD001

  • Jeon, Jeong-Ho;Yun-Jon Han;Tae-Gu kang;Eung-Soo Kim;Soon-Kwang Hong;Byeong-Chul Jeong
    • Journal of Microbiology and Biotechnology
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    • v.12 no.6
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    • pp.972-978
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    • 2002
  • Streptomyces sp. AD001 is a Gram-positive soil actinomycetes secreting an uncharacterized 2,4-dichlorophenol (DCP) oxidizing enzyme, whose activity is similar to the previously known Actinomycetes lignin-peroxidase (ALiP). This extracellular peroxidase was purified from Streptomyces sp. AD001 as a single protein band on an SDS-PACE by ammonium sulfate fractionation, Q-sepharose, concanavalin A, and Bio-Gel HTP column chromatographies. The molecular mass of the purified peroxidase was determined by SDS-PAGE to be 45.2 kDa, and 49.7 kDa with MALDI-TOF-MS, respectively. The highest level of peroxidase activity was observed at pH 7.5 and $30^{\circ}C$. The amino terminal sequence of the purified peroxidase (G-E-P-E-E-G-N-V-D-G-T-L) showed no significant homologies to my known proteins, suggesting that Streptomyces sp. AD001 may secrete a novel kind of bacterial peroxidase Initial rate kinetic data of the 2,4-DCP oxidation were best modeled with a random-binding bireactant system.

A Study on the Sasang Constitutional Symptom of Taeumin by Voice Characteristics (음향특성에 따른 태음인 체질병증(體質病證) 연구(硏究))

  • Kim, Dal-Rae
    • Journal of Sasang Constitutional Medicine
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    • v.19 no.1
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    • pp.90-97
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    • 2007
  • 1. Objectives and Methods This study was done to investigate the relationships of Sound parameters between Liver Heat Symptom and Esophagus Symptom of Taeumin using PSSC(Phonetic System of Sasang Constitution) in a sentence. Experimental Participants were 20 Korean adult males including, each 10 Liver Heat Symptom and Esophagus Symptom of Taeumin. 2. Results In Pitch segment, APQ segment and Shimmer segment, there were no significant differences between Liver Heat Symptom and Esophagus Symptom of Taeumin. In Octave segment, there were significant differences in Octave 1, Octave 3, Octave 4, Octave 6 of Liver Heat Symptom of Taeumin were significantly high compared with Esophagus Symptom of Taeumin. In Energy segment, FreQ Domain Total Sum / cnt(0), 0k-2k Total Sum,0k-2k sum dev., 2k-4k Total Sum, 2k-4k sum dev., A# Tot E, B__TOT_E, C__TOT_E, C# Tot E, D__TOT_E, A sum dev., A# sum dev., B sum dev., C sum dev., C# sum dev., Dsum dev., D# sum dev., E sum dev., F sum dev., F# sum dev., G sum dev., G# sum dev. of Liver Heat Symptom of Taeumin were significantly high compared with Esophagus Symptom of Taeumin. In Voice Recording time segment, Total Voice Recording Time, Voice Recording Time, Divide By Time3, Divide By Energy10, Total Unit, Max Unit Position, U_0 TO 3 of Liver Heat Symptom of Taeumin were significantly high compared with Esophagus Symptom of Taeumin. 3. Conclusion From above result, there is the postbility of efficiency quide constitutional sx. of Taeumin by Voice characteristics. More Soeumin, Soyangin and Taeyangin Symptoms are needed to determine Sasang Constitution using PSSC and to make PSSC effective.

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Evaluation of wind loads and wind induced responses of a super-tall building by large eddy simulation

  • Lu, C.L.;Li, Q.S.;Huang, S.H.;Tuan, Alex Y.;Zhi, L.H.;Su, Sheng-chung
    • Wind and Structures
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    • v.23 no.4
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    • pp.313-350
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    • 2016
  • Taipei 101 Tower, which has 101 stories with height of 508 m, is located in Taipei where typhoons and earthquakes commonly occur. It is currently the second tallest building in the world. Therefore, the dynamic performance of the super-tall building under strong wind actions requires particular attentions. In this study, Large Eddy Simulation (LES) integrated with a new inflow turbulence generator and a new sub-grid scale (SGS) model was conducted to simulate the wind loads on the super-tall building. Three-dimensional finite element model of Taipei 101 Tower was established and used to evaluate the wind-induced responses of the high-rise structure based on the simulated wind forces. The numerical results were found to be consistent with those measured from a vibration monitoring system installed in the building. Furthermore, the equivalent static wind loads on the building, which were computed by the time-domain and frequency-domain analysis, respectively, were in satisfactory agreement with available wind tunnel testing results. It has been demonstrated through the validation studies that the numerical framework presented in this paper, including the recommended SGS model, the inflow turbulence generation technique and associated numerical treatments, is a useful tool for evaluation of the wind loads and wind-induced responses of tall buildings.

A Study on the 43$0^{\circ}C$ Degradation Behavior of Cast Stainless Steel(CF8M) (III) - Evaluation of Elastic-Plastic Fracture Toughness - (주조 스테인리스강 CF8M의 43$0^{\circ}C$ 열화거동에 관한 연구 (III) - 탄소성 파괴인성 평가 -)

  • Gwon, Jae-Do;In, Jae-Hyeon;Park, Jung-Cheol;Choe, Seong-Jong;Park, Yun-Won
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.10 s.181
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    • pp.2405-2412
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    • 2000
  • A cast stainless steel may experience an embrittlement when it is exposed to approximately 30$0^{\circ}C$ for long period. In the present investigation, The three classes of the thermally aged CF8M specimie n are prepared using an artificially accelerated aging method. Namely, after the specimen are held for 300, 1800 and 3600hrs. at 43$0^{\circ}C$ respectively, the specimens are quenched in water to room temperature. Load versus load line displacement curves and J-R curves are obtained using the unloading compliance method. $J_{IC}$ values are obtained following ASTM E 813-87 and ASTM E 813-81 methods. In addition to these methods, JIC values are obtained using SZW(stretch zone width) method described in JSME S 001-1981. The results of the unloading compliance method are $J_Q$=485.7 kJ/m$^2$ for virgin material, $J_{IC}$ of the degraded materials associated with 300, 1800 and 3600hrs are obtained 369.25 kJ/m$^2$, 311.02 kJ/m$^2$, 276.7 kJ/m$^2$, respectively. The results of SZW method are similar to those of the unloading compliance method. Through the elastic-plastic fracture toughness test, it is found that the value of $J_{IC}$ is decreased with increasing of the aging time. The results obtained through the investigation can provide reference data for a leak before break(LBB) of reactor coolant system of nuclear power plants.

A New Approach for Hierarchical Optimization of Large Scale Non-linear Systems (대규모 비선형 시스템의 새로운 계층별 최적제어)

  • Park, Joon-Hoon;Kim, Jong-Boo
    • Journal of the Korean Institute of Telematics and Electronics T
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    • v.36T no.2
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    • pp.21-31
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    • 1999
  • This paper presents a new possibility of calculating optimal control for large scale which consist of non-linear dynamic sub-systems using two level hierarchical structures method. And the proposed method is based on the idea of block pulse transformation to simplify the algorithm and its calculation. This algorithm used an expansion around the equilibrium point of the system to fix the second and higher order terms. These terms are compensated for iteratively at the second level by providing a prediction for the states and controls which form of a part of the higher order terms. In this new approach the quadratic penalty terms are not used in the cost function. This allows convergence over a longer time horizon and also provides faster convergence. And the method is applied to the problem of optimization of the synchronous machine. Results show that the new approach is superior to conventional numerical method or other previous algorithm.

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Predicting Impacts of Climate Change on Sinjido Marine Food Web (기후변화로 인한 신지도 근해 해양먹이망 변동예측)

  • Kang, Yun-Ho;Ju, Se-Jong;Park, Young-Gyu
    • Ocean and Polar Research
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    • v.34 no.2
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    • pp.239-251
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    • 2012
  • The food web dynamics in a coastal ecosystem of Korea were predicted with Ecosim, a trophic flow model, under various scenarios of primary productivity due to ocean warming and ocean acidification. Changes in primary productivity were obtained from an earth system model 2.1 under A1B scenario of IPCC $CO_2$ emission and replaced for forcing functions on the phytoplankton group during the period between 2020 and 2100. Impacts of ocean acidification on species were represented in the model for gastropoda, bivalvia, echinodermata, crustacean and cephalopoda groups with effect sizes of conservative, medium and large. The model results show that the total biomass of invertebrate and fish groups decreases 5%, 11~28% and 14~27%, respectively, depending on primary productivity, ocean acidification and combined effects. In particular, the blenny group shows zero biomass at 2080. The zooplankton group shows a sudden increase at the same time, and finally reaches twice the baseline at 2100. On the other hand, the ecosystem attributes of the mean trophic level of the ecosystem, Shannon's H and Kempton's Q indexes show a similar reduction pattern to biomass change, indicating that total biomass, biodiversity and evenness shrink dynamically by impacts of climate change. It is expected from the model results that, after obtaining more information on climate change impacts on the species level, this study will be helpful for further investigation of the food web dynamics in the open seas around Korea.

A Web-based Conversational Agent (웹기반 대화형 에이전트)

  • 이승익;오성배
    • Journal of KIISE:Computing Practices and Letters
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    • v.9 no.5
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    • pp.530-540
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    • 2003
  • As the amount of information on Internet sites increases, it becomes more necessary to provide information in efficient ways. However, information search methods based on Boolean combination of keywords that most sites provide are difficult to express user's intention adequately so that there are numerous unexpected search results. This paper proposes a conversational agent that provides users with accurate information in a friendly manner through natural language conversation. The agent recognizes user's intention by applying finite state automata to natural language queries, utilizes the intention for structured pattern matching with response knowledge, and thus provides answers that are robust against changes in word order and consistent with the user's intention. To show its practical utility, the agent is applied to the problem of introducing a Web site. The results show that the conversational agent has the ability to provide accurate and friendly responses.