• Title/Summary/Keyword: Structure determination

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Studies on the quantitative determination of Capsaicin in various species of the genus Capsicum (고추중의 Capsaicin 정량(定量)에 관(關)한 연구(硏究))

  • Lee, Tae-Yeong;Park, Seong-O
    • Applied Biological Chemistry
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    • v.4
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    • pp.23-28
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    • 1963
  • Various species of the genus Capsicum contain in their fruits an intensively sharp and pungent substance, Capsaicin, which was first isolated in an almost pure state by Thresh. Containing the pungent principle, Capsicums are used extensively in food as a spice and in medicine as a rubefacient and carminative. Numerous methods have been proposed for the isolation, the chemical structure and the quantitative determination of Capsaicin. Modifying the several methods described before, the Capsaicin contents in various species of the genus Capsicum were determined as follows. (1) The isolation of pure Capsaicin was the essential first step for the determination of Capsaicin contents. Powdered cayenne pepper was extracted with acetone. By the method of ether alkali partition extraction slightly modified at this laboratory and by the recrystallization with light petroleum ether that was repeated ten times, the pure crystalline Capsaicin was obtained. Using this Capsaicin, the standard absorption curve was drawn with Beckman spectrophotometer model DU for the quantitative determination of Capsaicin. 92) The powdered sample was extracted in a Soxhlet extractor with ether-acetone solvent system(3:1) for 25 hours. Capsaicin in this ether-acetone extracts was efficiently separated in a pure state by paper partition chromatography using 58% methanol solution as developing agent. It was found that 58% methanol was one of the most valuable solvent to separate Capsaicin from impurities such as sterols, fatty acids, waxes and carotenoid pigments. (3) The colorimetric method modifying the Schulte-Kruger's method which consists of measuring the red color produced with diazobenzenesulphonic acid was used. Capsaicin in various species of the genus Capsicum was determined quantitatively with use of Beckman spectrophotometer model DU at $480\;m{\mu}$.

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Anaphoricity Determination of Zero Pronouns for Intra-sentential Zero Anaphora Resolution (문장 내 영 조응어 해석을 위한 영대명사의 조응성 결정)

  • Kim, Kye-Sung;Park, Seong-Bae;Park, Se-Young;Lee, Sang-Jo
    • Journal of KIISE:Software and Applications
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    • v.37 no.12
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    • pp.928-935
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    • 2010
  • Identifying the referents of omitted elements in a text is an important task to many natural language processing applications such as machine translation, information extraction and so on. These omitted elements are often called zero anaphors or zero pronouns, and are regarded as one of the most common forms of reference. However, since all zero elements do not refer to explicit objects which occur in the same text, recent work on zero anaphora resolution have attempted to identify the anaphoricity of zero pronouns. This paper focuses on intra-sentential anaphoricity determination of subject zero pronouns that frequently occur in Korean. Unlike previous studies on pair-wise comparisons, this study attempts to determine the intra-sentential anaphoricity of zero pronouns by learning directly the structure of clauses in which either non-anaphoric or inter-sentential subject zero pronouns occur. The proposed method outperforms baseline methods, and anaphoricity determination of zero pronouns will play an important role in resolving zero anaphora.

Determination and Predictability of Precipitation-type in Winter from a Ground-based Microwave Radiometric Profiler Radiometer (라디오미터를 이용한 겨울철 강수형태 결정 및 예측가능성 고찰)

  • Won, Hye Young;Kim, Yeon-Hee;Chang, Dong-Eon
    • Atmosphere
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    • v.20 no.3
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    • pp.229-238
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    • 2010
  • The 1,000~500 hPa thickness and the $0^{\circ}C$ isotherm at 850 hPa have been used as the traditional predictors for wintertime precipitation-type forecasts. New approaches are taking on added significance as preexistence method of determination for wintertime precipitation-type exhibits more or less prevalent false alarms. Moreover thicknesses and thermodynamic profiles from ordinary upper-air observation were not adequate to monitor the atmospheric structure. In this regard, Microwave radiometric profiler microwave radiometer is useful in wintertime precipitation-type forecasts because radiometric measurements provide soundings at high temporal resolution. In this study, the determination and the predictability of wintertime precipitation-type were examined by using the calculated thicknesses, temperature of 850 hPa (T850) from a microwave radiometer, and surface observation at National Center for Intensive Observation of severe weather (NCIO) located at Haenam, Korea. The critical values for traditional predictors (thickness of 1000~500 hPa and T850) were evaluated and adjusted to Haenam region because snow rarely occurred with a 1000-500 hPa thickness > 5,300 m and T850 > $-10^{\circ}C$. Three thicknesses (e.g., 1,000~850, 1000~700, and 850~700 hPa thickness), T850, surface air temperature, and wet-bulb temperature were also evaluated as the additional predictors. A simple nomogram and a flow chart were finally designed to determine the wintertime precipitation-type using the microwave radiometer. The skill scores for the predictability of precipitation-type determination are considerably improved and the predictors showed the temporal variations in 12 hours before precipitation. We can monitor the hit and run snowfall in winter successful by realtime watch of the predictors, especially in commutes of big cities.

Use of Molecular Replacement to Determine the Phases of Crystal Structure of Taq DNA Polymerase

  • Kim, Young-Soo;Suh, Se-Won
    • BMB Reports
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    • v.29 no.1
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    • pp.38-44
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    • 1996
  • Taq DNA polymerase from Thermus aquaticus has been shown to be very useful in the polymerase chain reaction method, which is being used for amplifying DNA. Not only does Taq DNA polymerase have high commercial value commercial value for the polymerase chain reaction application, but it is also important in studying DNA replication, because it is apparently an homologue to E. coli DNA polymerase I, which has long been used for DNA replication study (Lawyer et ai., 1993). The crystal structure determination of Taq DNA polymerase was initiated. An X-ray diffraction pattern breaks down a crystal structure into discrete sine waves in a Fourier series. The original shape of a crystal object in terms of electron density may be represented as the sum of those sine waves with varying amplitudes and phases in three dimensions. The molecular replacement method was initially employed to provide phase information for the structure of Taq DNA polymerase. The rotation search using the program MERLOT resulted in a solution peak with 5.4 r.m.s. PC-refinement of the X-PLOR program verified the result and also optimized the orientation angles. Next, the translation search using the X-PLOR program resulted in a unique solution peak with 7.35 r.m.s. In addition, the translation search indicated $P3_121$ to be the true space group out of two possible ones. The phase information from the molecular replacement was useful in the MIR phasing experiment.

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Fundamental period of infilled RC frame structures with vertical irregularity

  • Asteris, Panagiotis G.;Repapis, Constantinos C.;Foskolos, Filippos;Fotos, Alkis;Tsaris, Athanasios K.
    • Structural Engineering and Mechanics
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    • v.61 no.5
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    • pp.663-674
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    • 2017
  • The determination of the fundamental period of vibration of a structure is essential to earthquake design. Current codes provide formulas for the approximate estimation of the fundamental period of earthquake-resistant building systems. These formulas are dependent only on the height of the structure or number of storeys without taking into account the presence of infill walls into the structure, despite the fact that infill walls increase the stiffness and mass of the structure leading to significant changes in the fundamental period. Furthermore, such a formulation is overly conservative and unable to account for structures with geometric irregularities. In this study, which comprises the companion paper of previous published research by the authors, the effect of the vertical geometric irregularities on the fundamental periods of masonry infilled structures has been investigated, through a large set of infilled frame structure cases. Based on these results, an attempt to quantify the reduction of the fundamental period due to the vertical geometric irregularities has been made through a proposal of properly reduction factor.

Serviceability assessment of subway induced vibration of a frame structure using FEM

  • Ling, Yuhong;Gu, Jingxin;Yang, T.Y.;Liu, Rui;Huang, Yeming
    • Structural Engineering and Mechanics
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    • v.71 no.2
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    • pp.131-138
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    • 2019
  • It is necessary to predict subway induced vibration if a new subway is to be built. To obtain the vibration response reliably, a three-dimensional (3D) FEM model, consisting of the tunnel, the soil, the subway load and the building above, is established in MIDAS GTS NX. For this study, it is a six-story frame structure built above line 3 of Guangzhou metro. The entire modeling process is described in detail, including the simplification of the carriage load and the determination of model parameters. Vibration measurements have been performed on the site of the building and the model is verified with the collected data. The predicted and measured vibration response are used together to assess vibration level due to the subway traffic in the building. The No.1 building can meet work and residence comfort requirement. This study demonstrates the applicability of the numerical train-tunnel-soil-structure model for the serviceability assessment of subway induced vibration and aims to provide practical references for engineering applications.

Experimental study on rock-coal-rock composite structure with different crack characteristics

  • Li, Tan;Chen, Guangbo;Li, Qinghai
    • Geomechanics and Engineering
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    • v.29 no.4
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    • pp.377-390
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    • 2022
  • The stability of the roof rock-coal pillar-floor rock composite structure is of great significance to coal mine safety production. The cracks existing in the composite structure seriously affect the stability of the roof rock-coal pillar-floor rock composite structure. The numerical simulation tests of rock-coal-rock composite structures with different crack characteristics were carried out to reveal the composite structures' mechanical properties and failure mechanisms. The test results show that the rock-coal-rock composite structure's peak stress and elastic modulus are directly proportional to the crack angle and inversely proportional to the crack length. The smaller the crack angle, the more branch cracks produced near the main control crack in the rock-coal-rock composite structure, and the larger the angle between the main control crack and the crack. The smaller the crack length, the larger the width of the crack zone. The impact energy index of the rock-coal-rock composite structure decreases first and then increases with the increase of crack length and increases with the increase of crack angle. The functional relationships between the different crack characteristics, peak stress, and impact energy index are determined based on the sensitivity analysis. The determination of the functional relationship can fully grasp the influence of the crack angle and the crack length on the peak stress and impact energy index of the coal-rock composite structure. The research results can provide a theoretical basis and guidance for preventing the instability and failure of the coal pillar-roof composite structure.

A Study on the recognition of local name using Spatio-Temporal method (Spatio-temporal방법을 이용한 지역명 인식에 관한 연구)

  • 지원우
    • Proceedings of the Acoustical Society of Korea Conference
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    • 1993.06a
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    • pp.121-124
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    • 1993
  • This paper is a study on the word recognition using neural network. A limited vocabulary, speaker independent, isolated word recognition system has been built. This system recognizes isolated word without performing segmentation, phoneme identification, or dynamic time wrapping. It needs a static pattern approach to recognize a spatio-temporal pattern. The preprocessing only includes preceding and tailing silence removal, and word length determination. A LPC analysis is performed on each of 24 equally spaced frames. The PARCOR coefficients plus 3 other features from each frame is extracted. In order to simplify a structure of neural network, we composed binary code form to decrease output nodes.

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