• Title/Summary/Keyword: SMM

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FDTD를 이용한 Suspended Membrane Microstrip(SMM) Line의 해석

  • 남윤권
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2001.11a
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    • pp.345-346
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    • 2001
  • 그림 1에서 볼 수 있는 것처럼 신호선을 지지하고 있는 membrane은 SMM line의 전체 크기에 비해 아주 작다. 따라서 uniform grid를 ㅣ용해서 이러한 구조를 해석하게 되면 해석점이 너무 많아져서 많은 메모리를 필요로 하게 되어 일반적인 컴퓨터로는 해석이 어려워지며, non-uniform grid를 사용한다 해도 해석점의 수는 줄일 수 있느나 가장 작은 grid의 크기가 membrane의 크기에 의해서 정해지므로 FDTD 해석에 사용되는 time-step이 아주 작아져서 해석하는데 시간이 오래 걸린게 된다.

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A Comparative Legal Study of Germany, the United Kingdom, Japan and Korea for the Regulations on Special Management Materials (우리나라 산업안전보건법상 특별관리물질 규정에 대한 독일, 영국 및 일본과의 비교법적 고찰)

  • Choi, Sangjun;Phee, Young Gyu;Kim, Shinbum;Kim, Won
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.23 no.2
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    • pp.137-147
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    • 2013
  • Objectives: This study was conducted in order to evaluate the limitations of the regulations on the safety and health standards for special management materials(SMM) under the Industrial Safety and Health Act in Korea. Methods: Hazardous chemicals management systems in Germany(Hazardous Substances Ordinance), the UK(Control of Substances Hazardous to Health Regulations), Japan(Ordinance on Prevention of Hazards due to Specified Chemical Substances) and Korea(Regulation of Occupational Safety and Health Standards, ROSHS) were investigated and compared in terms of 14 items. Results: Among the 14 items, we eventually found seven items which should be amended: 1) definition and scope, 2) general duties clause, 3) principles of management, 4) preventive measures, 5) control measures, 6) risk assessment, and 7) record keeping. The principal limitations of Korean regulations in comparison with those of other countries were that there were no preventive measures such as substitution, and no principles of good practices for the control of exposure to SMM. In terms of control measures, there were no regulations on suitable workplace design, reducing the number of exposed workers, reducing the level and duration of exposure, and reducing the quantity of hazardous substances in ROSHS. Conclusions: Based on the results of this study, ROSHS should be complemented with preventive measures and the principles of management related to SMM. According to the suggestions, an employer who deals with SMM should preferably consider the possibility of substitution and perform substitution so far as is reasonably practicable.

Resolution of Molecular Species of the Triacylglycerol Containing Petroselinic Acid $(cis-C_{18:1{\omega}12)$ by Silver Ion-HPLC

  • Joh, Yong-Goe;Kim, Seong-Jin
    • Journal of the Korean Applied Science and Technology
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    • v.22 no.4
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    • pp.339-348
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    • 2005
  • On the analysis of triacylglycerol (TG) from the kernels of Acanthopanax sessiliflorus by reversed phase-HPLC, it was separated into three main fractions of PN 44, 46 and 48, according to partition number (PN). On the contrary, it could be clearly classified into seven fractions of SMM, MMM, SMD, MMD, SDD, MDD and MDT by silver ion-HPLC by the number of double bond in the acyl chains of TG species. But resolution of so-called critical pairs of TG molecular species such as molecular pairs of $P_eLL$ $[C_{18:1{\omega}12}/(C_{18:2{\omega}6)2}]$ and OLL $[C_{18:1{\omega}9}/(C_{18:2{\omega}6)2}]$ and OOL $[(C_{18:1{\omega}9)2}/C_{18:2{\omega}6]$, and $P_eP_eL$ $[(C_{18:2{\omega}12)2}/C_{18:1{\omega}6]$ was not achieved $(P_e;$ petroselinic acid, L; linoleic acid, O; oleic acid). On the other hand, TG extracted from Aralia continentalis kernels were also fractionated into seven groups of SSM, SMM, MMM, SMD, MMD, SDD and MDD (S; saturated acid, M; monoenoic acid, D; dienoic acid) by silver ion-HPLC, although it's were classified into three groups of PN 44, 46 and 48 by reversed phase-HPLC. The fractions of SMM, MMM, MMD and MDD were divided into two subfractions, respectively; the fractions of SMM, MMM, MMD and MDD were resolved into the subfraction of $PP_e/P_e$ and POO (critical pairs from each other), that of $P_e/P_e/P_e$ and OOO, that of $P_e/P_e/L$ and OOL, and that of $P_e/L/L$ and OLL.

Optimization of Culture Conditions and Analysis of Plasmid Stability of a Transformant Bacillus subtilis for Cytidine Deaminase Production

  • Kim, Soo-Hyun;Song, Bang-Ho;Lee, Yong-Hyun
    • Journal of Microbiology and Biotechnology
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    • v.1 no.2
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    • pp.116-120
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    • 1991
  • The transformant Bacillus subtilis ED213 carrying the pSO100 which cloned the cdd gene encoding cytidine deaminase (cytidine /2'-deoxycytidine aminohydrolase, EC 3.5.4.5, CDase) originated from wild type B. subtilis was cultivated in Spizizen minimal medium (SMM). To overcome poor expression of the cdd gene in SMM medium, the medium compositions and growth conditions were optimized. The optimized medium compositions and growth conditions were cytidine concentration of 80 mg/l, glycerol of 25 g/l, and $(NH_4)_2SO_4$ of 10 g/l, along with $37^{\circ}C$ and pH 7.0. The intracellular CDase production was increased 3 times from 1,000 unit/ml to 3,200 unit/ml, and extracellular CDase also increased from nearly undetectable amounts to 1,500 unit/ml. The cytidine concentration was signified as the most critical compositional factor for overproduction of CDase by increasing the cell density mainly in culture broth. The plasmids were more stable in cells that were grown in original SMM medium with stability of 90% compared to those grown in optimized SMM medium with stability of 80% after 48 hours cultivation. The most active amplification of plasmid was occurred in the logarithmic phase, which showed a value around four times higher than the initial copy number. In the exponential phase, the CDase production was closely related to the plasmid copy number along with the cell density. However, it was not accorded with cell density at the stationary phase.

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An Efficient Location Management Scheme in Locaton - Aware Computing (위치 인식 컴퓨팅에서 효율적인 위치 관리 기법)

  • MoonBae, Song;KwangJin, Park;Chong-Sun, Hwang
    • Journal of KIISE:Databases
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    • v.31 no.5
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    • pp.505-515
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    • 2004
  • One of the most important issue in location-aware computing is tracking moving objects efficiently. To this end, an efficient protocol which updates location information in a location server is highly needed. In fact, the performance of a location update strategy highly depends on the assumed mobility pattern. In most existing works, however, the mobility issue has been disregarded and too simplified as linear function of time. In this paper, we propose a new mobility model, called state-based mobility model (SMM) to provide more generalized framework for both describing the mobility and updating location information of complexly moving objects. We also introduce the state-based location update protocol (SLUP) based on this mobility model. Using experimental comparison, we illustrate that the proposed technique is many times better in reducing location update cost and the communication bandwidth consumption.

DETERMINATION OF GPS HEIGHT WITH INCORPORATION OF USING SURFACE METEOROLOGICAL MEASUREMENTS

  • Wang, Chuan-Sheng;Liou, Yuei-An;Yeh, Ta-Kang
    • Proceedings of the KSRS Conference
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    • 2008.10a
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    • pp.313-316
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    • 2008
  • Although the positioning accuracy of the Global Positioning System (GPS) has been studied extensively and used widely, it is still limited due to errors from sources such as the ionospheric effect, orbital uncertainty, antenna phase center variation, signal multipath and tropospheric influence. This investigation addresses the tropospheric effect on GPS height determination. Data obtained from GPS receivers and co-located surface meteorological instruments in 2003 are adopted in this study. The Ministry of the Interior (MOl), Taiwan, established these GPS receivers as continuous operating reference stations. Two different approaches, parameter estimation and external correction, are utilized to correct the zenith tropospheric delay (ZTD) by applying the surface meteorological measurements (SMM) data. Yet, incorrect pressure measurement leads to very poor accuracy. The GPS height can be affected by a few meters, and the root-mean-square (rms) of the daily solution ranges from a few millimeters to centimeters, no matter what the approach adopted. The effect is least obvious when using SMM data for the parameter estimation approach, but the constant corrections of the GPS height occur more often at higher altitudes. As for the external correction approach, the Saastamoinen model with SMM data makes the repeatability of the GPS height maintained at few centimeters, while the rms of the daily solution displays an improvement of about 2-3 mm.

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The impact of co-creation implementation on the performance of small and medium manufacturers: an empirical study (Co-creation 활용에 따른 중소제조업체의 기업성과에 관한 연구)

  • Kim, Dong Wan;Lee, Sang M.;Hong, Soon Goo;Kim, Jong-Weon
    • The Journal of Information Systems
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    • v.24 no.4
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    • pp.1-19
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    • 2015
  • Purpose Co-creation is a form of collaboration to create joint values with participation of diverse interested parties. It has been introduced by large companies at an early stage and due to changes in management environment, the scope of its concept has been expanding to the SMM(Small and Medium Manufactures). The objective of this study is to examine the impact of Co-creation on SMM's non-financial and financial performance. Design/methodology/approach Based on literature review, the research model was developed. To test this research model, we collected 188 questionnaires with SMM which utilized Co-creation and supplied parts to the companies. The t-test and ANOVA were employed for the analysis of data Findings The research result showed that the difference in business performance between the groups with much use of Co-creation and those with little use of Co-creation, there was significant difference in both non-financial and financial performance. In addition, non-financial and financial performance were different among four implementation behavior of Co-creation including Common value, Information share, Risk benefit, and Mutual benefit.

Development of the Enterprise Process Evaluation for Small and Medium Business Consulting (중소기업 경영컨설팅을 위한 전사적 프로세스 평가모델 개발)

  • Cho, Jey-Ryong;Lee, Heejung
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.35 no.4
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    • pp.41-47
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    • 2012
  • To adapt to a rapidly changing business environment, introduction of new management techniques and innovative activities are crucial. In the case of small and medium companies, the compensation for scarce management resources and sustainable development can be obtained from advantage of management consulting. In this study, we propose the enterprise process evaluation model for small and medium business consulting, which can deploy the process improvement activities with considering the process maturity level within an organization. The process evaluation area of proposed Small and Medium Business, Staged Maturity Model (SMB-SMM) consists of four following parts: supply management, demand management, business management, and research and development (R&D) management. For each area, we set goals and also define the practices to achieve their goals respectively. By applying the SMB-SMM model to the small and medium sized companies, the process maturity level can be defined. And then to overcome the gap between the goals and evaluation results, the customized management consulting activities can be drawn from the predefined consulting approaches from the SMB-SMM.

Numerical Analysis on the Effect of High-Shear in a Rotor-Stator Mixer (Rotor-Stator Mixer 전단효과에 관한 수치 해석적 연구)

  • Yeum, Sang Hoon;Lee, Seok Soon
    • Journal of Aerospace System Engineering
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    • v.13 no.5
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    • pp.39-48
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    • 2019
  • The turbulent flow in the rotor-stator mixer is based on shear characteristics generated by the interaction of the stator with the rotor rotating at high speed. In this study, the flow characteristics analysis of the unsteady state generated by the interaction of the rotor and the stator in the prototype model of the emulsion-fuel related mixer development was performed with the MRF and SMM by applying the ANSYS FLUENT $k-{\varepsilon}$ (RKE) turbulence model. The behavior and shear characteristics of the flow particles generated at the interface between the designed rotor and stator, and trends such as velocity distribution and turbulence eddy dissipation, were predicted and verified using the CFD analysis.

Development of Sequential Mixing Model for Analysis of Shear Flow Dispersion (전단류 분산 해석을 위한 순차혼합모형의 개발)

  • Seo, Il Won;Son, Eun Woo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.4B
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    • pp.335-344
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    • 2006
  • In this study, sequential mixing model (SMM) was proposed based on the Taylor's theory which can be summarized as the fact that longitudinal advection and transverse diffusion occur independently and then the balance between the longitudinal shear and transverse mixing maintains. The numerical simulation of the model were performed for cases of different mixing time and transverse velocity distribution, and the results were compared with the solutions of 1-D longitudinal dispersion model (1-D LDM) and 2-D advection-dispersion model (2-D ADM). As a result it was confirmed that SMM embodies the Taylor's theory well. By the comparison between SMM and 2-D ADM, the relationship between the mixing time and the transverse diffusion coefficient was evaluated, and thus SMM can integrate 2-D ADM model as well as 1-D LDM model and be an explanatory model which can represents the shear flow dispersion in a visible way. In this study, the predicting equation of the longitudinal dispersion coefficient was developed by fitting the simulation results of SMM to the solution of 1-D LDM. The verification of the proposed equation was performed by the application to the 38 sets of field data. The proposed equation can predict the longitudinal dispersion coefficient within reliable accuracy, especially for the river with small width-to-depth ratio.