• Title/Summary/Keyword: mass uncertainty

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The Adoption and Diffusion of Semantic Web Technology Innovation: Qualitative Research Approach (시맨틱 웹 기술혁신의 채택과 확산: 질적연구접근법)

  • Joo, Jae-Hun
    • Asia pacific journal of information systems
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    • v.19 no.1
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    • pp.33-62
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    • 2009
  • Internet computing is a disruptive IT innovation. Semantic Web can be considered as an IT innovation because the Semantic Web technology possesses the potential to reduce information overload and enable semantic integration, using capabilities such as semantics and machine-processability. How should organizations adopt the Semantic Web? What factors affect the adoption and diffusion of Semantic Web innovation? Most studies on adoption and diffusion of innovation use empirical analysis as a quantitative research methodology in the post-implementation stage. There is criticism that the positivist requiring theoretical rigor can sacrifice relevance to practice. Rapid advances in technology require studies relevant to practice. In particular, it is realistically impossible to conduct quantitative approach for factors affecting adoption of the Semantic Web because the Semantic Web is in its infancy. However, in an early stage of introduction of the Semantic Web, it is necessary to give a model and some guidelines and for adoption and diffusion of the technology innovation to practitioners and researchers. Thus, the purpose of this study is to present a model of adoption and diffusion of the Semantic Web and to offer propositions as guidelines for successful adoption through a qualitative research method including multiple case studies and in-depth interviews. The researcher conducted interviews with 15 people based on face-to face and 2 interviews by telephone and e-mail to collect data to saturate the categories. Nine interviews including 2 telephone interviews were from nine user organizations adopting the technology innovation and the others were from three supply organizations. Semi-structured interviews were used to collect data. The interviews were recorded on digital voice recorder memory and subsequently transcribed verbatim. 196 pages of transcripts were obtained from about 12 hours interviews. Triangulation of evidence was achieved by examining each organization website and various documents, such as brochures and white papers. The researcher read the transcripts several times and underlined core words, phrases, or sentences. Then, data analysis used the procedure of open coding, in which the researcher forms initial categories of information about the phenomenon being studied by segmenting information. QSR NVivo version 8.0 was used to categorize sentences including similar concepts. 47 categories derived from interview data were grouped into 21 categories from which six factors were named. Five factors affecting adoption of the Semantic Web were identified. The first factor is demand pull including requirements for improving search and integration services of the existing systems and for creating new services. Second, environmental conduciveness, reference models, uncertainty, technology maturity, potential business value, government sponsorship programs, promising prospects for technology demand, complexity and trialability affect the adoption of the Semantic Web from the perspective of technology push. Third, absorptive capacity is an important role of the adoption. Fourth, suppler's competence includes communication with and training for users, and absorptive capacity of supply organization. Fifth, over-expectance which results in the gap between user's expectation level and perceived benefits has a negative impact on the adoption of the Semantic Web. Finally, the factor including critical mass of ontology, budget. visible effects is identified as a determinant affecting routinization and infusion. The researcher suggested a model of adoption and diffusion of the Semantic Web, representing relationships between six factors and adoption/diffusion as dependent variables. Six propositions are derived from the adoption/diffusion model to offer some guidelines to practitioners and a research model to further studies. Proposition 1 : Demand pull has an influence on the adoption of the Semantic Web. Proposition 1-1 : The stronger the degree of requirements for improving existing services, the more successfully the Semantic Web is adopted. Proposition 1-2 : The stronger the degree of requirements for new services, the more successfully the Semantic Web is adopted. Proposition 2 : Technology push has an influence on the adoption of the Semantic Web. Proposition 2-1 : From the perceptive of user organizations, the technology push forces such as environmental conduciveness, reference models, potential business value, and government sponsorship programs have a positive impact on the adoption of the Semantic Web while uncertainty and lower technology maturity have a negative impact on its adoption. Proposition 2-2 : From the perceptive of suppliers, the technology push forces such as environmental conduciveness, reference models, potential business value, government sponsorship programs, and promising prospects for technology demand have a positive impact on the adoption of the Semantic Web while uncertainty, lower technology maturity, complexity and lower trialability have a negative impact on its adoption. Proposition 3 : The absorptive capacities such as organizational formal support systems, officer's or manager's competency analyzing technology characteristics, their passion or willingness, and top management support are positively associated with successful adoption of the Semantic Web innovation from the perceptive of user organizations. Proposition 4 : Supplier's competence has a positive impact on the absorptive capacities of user organizations and technology push forces. Proposition 5 : The greater the gap of expectation between users and suppliers, the later the Semantic Web is adopted. Proposition 6 : The post-adoption activities such as budget allocation, reaching critical mass, and sharing ontology to offer sustainable services are positively associated with successful routinization and infusion of the Semantic Web innovation from the perceptive of user organizations.

Application of Dynamic Reaction Cell - Inductively Coupled Plasma Mass Spectrometry for the Determination of Calcium by Isotope Dilution Method (반응셀 유도결합플라스마 질량분석분석기를 이용한 칼슘 동위원소비율의 측정과 동위원소희석법의 적용)

  • Suh, Jungkee;Yim, Yonghyeon;Hwang, Euijin;Lee, Sanghak
    • Analytical Science and Technology
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    • v.15 no.5
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    • pp.417-426
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    • 2002
  • Inductively Coupled Plasma Dynamic Reaction Cell Quadrupole Mass Spectrometry (ICP-DRC-QMS) was characterized for the detection of the six naturally occurring calcium isotopes. The effect of the operating conditions of the DRC system was studied to get the best signal-to-noise ratio. This experiment shows that the potentially interfering ions such as $Ar^+$, ${CO_2}^+$, ${NO_2}^+$, $CNO^+$ at the calcium masses m/z 40, 42, 43, 44 and 48 were removed by flowing $NH_3$ gas at the rate of 0.7 mL/min $NH_3$ as reactive cell gas in the DRC with a RPq value (rejection parameter) of 0.6. The limits of detection for $^{40}Ca$, $^{42}Ca$, $^{43}Ca$, $^{44}Ca$, and $^{48}Ca$ were 1, 29, 169, 34, and 15 pg/mL, respectively. This method was applied to the determination of calcium in synthetic food digest samples (CCQM-P13) provided by LGC for international comparison. The isotope dilution method was used for the determination of calcium in the samples. The uncertainty evaluation was performed according to the ISO/GUM and EURACHEM guidelines. The determined mean concentration and its expanded uncertainty of calcium was ($66.4{\pm}1.2$) mg/kg. In order to assess our method, two reference samples, Riverine Water reference sample (NRCC SLRS-3) and Trace Elements in Water reference sample (NIST SRM 1643d), were analyzed.

Analysis of sorbic acid in tea-drink using isotope dilution liquid chromatography tandem mass spectrometry (ID-LC/MS/MS) (동위원소희석 액체 크로마토그래피-질량분석법을 이용한 차음료 중의 소르빈산의 분석)

  • Ahn, Seong-Hee;Lee, In-Sun;Kim, Byung-Joo
    • Analytical Science and Technology
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    • v.25 no.1
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    • pp.25-32
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    • 2012
  • Isotope dilution mass spectrometry (ID-MS) based on liquid chromatography tandem mass spectrometry (LC/MS/MS) was developed for the accurate determination of sorbic acid in tea-drink. An isotope analogue of sorbic acid, $^{13}C_2$-sorbic acid, was obtained by custom synthesis. MS was operated in the negative mode with selected reaction monitoring (SRM) mode of $[M-H]^-$ ${\rightarrow}$ $[M-CO_2H]^-$ channel at m/z 111 ${\rightarrow}$ 67 for sorbic acid and at m/z 113 ${\rightarrow}$ 68 for its isotope analogue. Chromatographic separation was accomplished with a C18 column and an isocratic mobile phase of 55% of 50 mM ammonium acetate (pH 4.5) and 45% of methanol. Homogeneous reference materials were prepared for validation of this method, including repeatability and reproducibility tests, by fortifying tea-drink with sorbic acid in our laboratory. Repeatability and reproducibility studies showed that the ID-LC/MS method is a reliable and reproducible method which provides less than 3.8% of relative standard deviation (RSD) for the analysis of sorbic acid.

Size-resolved Source Apportionment of Ambient Particles by Positive Matrix Factorization at Gosan, Jeju Island during ACE-Asia (PMF 분석을 이용한 ACE-Asia 측정기간 중 제주 고산지역 입자상 물질의 입경별 발생원 추정)

  • Moon K.J.;Han, J.S.;Kong, B.J.;Jung, I.R.;Cliff Steven S.;Cahill Thomas A.;Perry Kelvin D.
    • Journal of Korean Society for Atmospheric Environment
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    • v.22 no.5
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    • pp.590-603
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    • 2006
  • Size-and time-resolved aerosol samples were collected using an eight-stage Davis rotating unit for monitoring (DRUM) sampler from 23 March to 29 April 2001 at Gosan, Jeju Island, Korea, which is one of the super sites of Asia-Pacific Regional Aerosol Characterization Experiment(ACE-Asia). These samples were analyzed using synchrotron X-ray fluorescence for 3-hr average concentrations of 19 elements including Al, Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, and Pb. The size-resolved data sets were then analyzed using the positive matrix factorization(PMF) technique to identify possible sources and estimate their contributions to particulate matter mass. PMF analysis uses the uncertainty of the measured data to provide an optimal weighting. Twelve sources were resolved in eight size ranges($0.09{\sim}12{\mu}m$) and included continental soil, local soil, sea salt, biomass/biofuel burning, coal combustion, oil combustion, municipal incineration, nonferrous metal source, ferrous metal source, gasoline vehicle, diesel vehicle, and volcanic emission. The PMF result of size-resolved source contributions showed that natural sources represented by local soil, sea salt, continental soil, and volcanic emission contributed about 79% to the predicted primary particulate matter(PM) mass in the coarse size range ($1.15{\sim}12{\mu}m$) while anthropogenic sources such as coal combustion and biomass/biofuel burning contributed about 58% in the fine size range($0.56{\sim}2.5{\mu}m$). The diesel vehicle source contributed mostly in ultra-fine size range($0.09{\sim}0.56{\mu}m$) and was responsible for about 56% of the primary PM mass.

Accurate determination of chloramphenicol in meat by isotope dilution liquid chromatography mass spectrometry (ID-LC/MS) (동위원소희석 액체크로마토그래피-질량분석법을 이용한 육류 중 클로람페니콜의 정밀한 정량 분석에 관한 연구)

  • Song, Hye-Min;Kim, Byung-Joo;Jeong, Hyuk;Ahn, Seong-Hee
    • Analytical Science and Technology
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    • v.23 no.6
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    • pp.524-530
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    • 2010
  • Chloramphenicol is one of the most effective antibiotics for treatment of food-producing animals for typhoid fever. However, it has been reported that it caused severe side effects such as aplastic anemia in human, therefore the use of chloramphenicol for food-producing animal is prohibited by European Union and other countries. In this study, the analytical method using isotope dilution liquid chromatography-mass spectrometry (ID-LC/MS) was established for accurate determination of chloramphenicol in meat. Chloramphenicol was extracted with ethylacetate from porcine and solid phase extraction cartridge was used for enhancing the recovery. The residue of chloramphenicol in porcine was analyzed using the liquid chromatography mass spectrometer (LC/MS) interfaced with electrospray ionization source. Analysis was performed in negative mode with selected reaction mornitoring mode at m/z 321${\rightarrow}$257 of $[M-H]^-$ ${\rightarrow}$ $[M-H-(HCOCl)]^-$ and m/z 326 ${\rightarrow}$ 262 channels for its isotope. The established method was tested using fortified samples at the level of 0.2 1, 10, $25\;{\mu}g$/kg and analytical results agreed with the gravimetrically fortified values within their uncertainties. This method was validated by analyzing a certified reference material, BCR 445, from IRMM (Institute for Reference Materials and Measurement). Our measurement values agreed with the certified value within their uncertainties. The uncertainty of our measured value was much lower than that the certified value from IRMM.

Statistical Analysis of Geometric Parameters and Rock Conditions of Pick Cutters for Roadheaders (로드헤더용 픽커터의 형상변수와 암반조건에 대한 통계적 분석)

  • Soo-Ho Chang;Tae-Ho Kang;Chulho Lee;Soon-Wook Choi
    • Tunnel and Underground Space
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    • v.33 no.5
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    • pp.414-424
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    • 2023
  • In this study, a total of 326 data on a variety of geometric parameters of pick cutters and the corresponding cuttable rock conditions were collected and built as a database. Statistical analysis of the database showed that there is a significant positive correlation between the parameters that define the geometry of a pick cutter, especially between the parameters related to the length of a pick cutter and the geometry of a tungsten carbide insert. The diameter of a pick cutter shaft was also strongly correlated with the geometry of the inserts. On the other hand, it was difficult to find a clear correlation between the parameters for the rock conditions defined by the four conditions and the geometric parameters of pick cutters, which may be due to the uncertainty of the rock mass and the fact that the application of a pick cutter is presented as a range rather than a numerical single value. However, the mean values of geometric parameters of pick cutters tend to increase as a rock mass becomes harder. However, the pick length parameters are found to decrease as a rock mass becomes harder, which may be a way to reduce the moments that can occur when using long pick cutters in a hard rock condition.

Scaling up of single fracture using a spectral analysis and computation of its permeability coefficient (스펙트럼 분석을 응용한 단일 균열 규모확장과 투수계수 산정)

  • 채병곤
    • The Journal of Engineering Geology
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    • v.14 no.1
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    • pp.29-46
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    • 2004
  • It is important to identify geometries of fracture that act as a conduit of fluid flow for characterization of ground water flow in fractured rock. Fracture geometries control hydraulic conductivity and stream lines in a rock mass. However, we have difficulties to acquire whole geometric data of fractures in a field scale because of discontinuous distribution of outcrops and impossibility of continuous collecting of subsurface data. Therefore, it is needed to develop a method to describe whole feature of a target fracture geometry. This study suggests a new approach to develop a method to characterize on the whole feature of a target fracture geometry based on the Fourier transform. After sampling of specimens along a target fracture from borehole cores, effective frequencies among roughness components were selected by the Fourier transform on each specimen. Then, the selected effective frequencies were averaged on each frequency. Because the averaged spectrum includes all the frequency profiles of each specimen, it shows the representative components of the fracture roughness of the target fracture. The inverse Fourier transform is conducted to reconstruct an averaged whole roughness feature after low pass filtering. The reconstructed roughness feature also shows the representative roughness of the target subsurface fracture including the geometrical characteristics of each specimen. It also means that overall roughness feature by scaling up of a fracture. In order to identify the characteristics of permeability coefficients along the target fracture, fracture models were constructed based on the reconstructed roughness feature. The computation of permeability coefficient was performed by the homogenization analysis that can calculate accurate permeability coefficients with full consideration of fracture geometry. The results show a range between $10^{-4}{\;}and{\;}10^{-3}{\;}cm/sec$, indicating reasonable values of permeability coefficient along a large fracture. This approach will be effectively applied to the analysis of permeability characteristics along a large fracture as well as identification of the whole feature of a fracture in a field scale.

Comparison of Nitrogen Dioxide Retrieved by MAX-DOAS and OMI measurements in Seoul (지상원격측정 MAX-DOAS 시스템과 위성 OMI센서로 서울에서 산출된 이산화질소 층적분농도의 비교연구)

  • Lee, Hanlim
    • Korean Journal of Remote Sensing
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    • v.29 no.2
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    • pp.235-241
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    • 2013
  • $NO_2$ vertical column densities were retrieved via ground based Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) measurements for the first time for 6 months over the spring season in 2007 and 2008 in Seoul, one the megacities in the Northeast Asia. The retrieved $NO_2$ vertical column densities were compared with those obtained from space borneOzone Monitoring Instrument (OMI). Over the entire measurement period, the $NO_2$ vertical column densities measured by MAX-DOAS ranged from $1.0{\times}10^{15}molec{\cdot}cm^{-2}$ to $6.0{\times}10^{16}molec{\cdot}cm^{-2}$ while those obtained by OMI ranged $1.0{\times}10^{15}molec{\cdot}cm^{-2}$ to $7.0{\times}10^{16}molec{\cdot}cm^{-2}$. The correlation coefficient between $NO_2$ vertical column densities obtained from MAX-DOAS and OMI is 0.73 for the entire measurement period whereas the correlation coefficient of 0.85 is found for the dates under the clear sky condition. The cloudy condition is thought to play a major role in increase in uncertainty of the retrieved OMI $NO_2$ vertical column densities since air mass factor may induce high uncertainty due to the lack of cloud and aerosol vertical distribution information.

Receptor Model(CMB) and Source Apportionments of VOCs in Seoul Metropolitan Area (수용모델(CMB)을 이용한 수도권 VOCs의 배출원별 기여율 추정)

  • Han, Jin-Seok;Hong, Y.D.;Shin, S.A.;Lee, S.U.;Lee, S.J.
    • Journal of Environmental Impact Assessment
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    • v.14 no.4
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    • pp.227-235
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    • 2005
  • Source contribution for VOCs collected in Seoul metropolitan area was conducted using PAMs (Photochemical assessment monitoring system) data and CMB(Chemical Mass Balance) model8.0, in order to estimate spatial and temporal variations of VOCs source contribution in that area, and also to compare with corresponding emission inventory. VOCs data used in model calculation were collected at 6 different sites of PAMs(Seokmori, Guwoldong, Simgokdong, Bulgwangdong, Jeongdong and Yangpyeong) and 22 out of 56 VOCs species were analyzed from June 2002 to march 2003 and used for CMB model estimation. The result showed that vehicle exhaust, coating and energy combustion were important sources of VOCs in Seoul metropolitan area, averaging 32.6%, 25.5% and 25.1%, respectively. In this study as well as other references, it was revealed that vehicle exhaust is the main contributor of urban area VOCs, but there is remarkable contrast between emission inventory and model estimation. Vehicle exhaust portion is seriously underestimated while coating is usually overestimated in emission estimates, compared to CMB results. Therefore, it is considered to assert and confirm the uncertainty of emission estimates and clarify the distinction between two other source apportionment methods.

Real-time hybrid substructuring of a base isolated building considering robust stability and performance analysis

  • Avci, Muammer;Botelho, Rui M.;Christenson, Richard
    • Smart Structures and Systems
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    • v.25 no.2
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    • pp.155-167
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    • 2020
  • This paper demonstrates a real-time hybrid substructuring (RTHS) shake table test to evaluate the seismic performance of a base isolated building. Since RTHS involves a feedback loop in the test implementation, the frequency dependent magnitude and inherent time delay of the actuator dynamics can introduce inaccuracy and instability. The paper presents a robust stability and performance analysis method for the RTHS test. The robust stability method involves casting the actuator dynamics as a multiplicative uncertainty and applying the small gain theorem to derive the sufficient conditions for robust stability and performance. The attractive feature of this robust stability and performance analysis method is that it accommodates linearized modeled or measured frequency response functions for both the physical substructure and actuator dynamics. Significant experimental research has been conducted on base isolators and dampers toward developing high fidelity numerical models. Shake table testing, where the building superstructure is tested while the isolation layer is numerically modeled, can allow for a range of isolation strategies to be examined for a single shake table experiment. Further, recent concerns in base isolation for long period, long duration earthquakes necessitate adding damping at the isolation layer, which can allow higher frequency energy to be transmitted into the superstructure and can result in damage to structural and nonstructural components that can be difficult to numerically model and accurately predict. As such, physical testing of the superstructure while numerically modeling the isolation layer may be desired. The RTHS approach has been previously proposed for base isolated buildings, however, to date it has not been conducted on a base isolated structure isolated at the ground level and where the isolation layer itself is numerically simulated. This configuration provides multiple challenges in the RTHS stability associated with higher physical substructure frequencies and a low numerical to physical mass ratio. This paper demonstrates a base isolated RTHS test and the robust stability and performance analysis necessary to ensure the stability and accuracy. The tests consist of a scaled idealized 4-story superstructure building model placed directly onto a shake table and the isolation layer simulated in MATLAB/Simulink using a dSpace real-time controller.