• Title/Summary/Keyword: effective parameter

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Development of the Empirical Model for Estimating the Delivered Pollutant Loads Considering Geomorphic and Hydraulic Characteristics (유역형상과 수리특성을 고려한 경험론적 유달부하식 개발)

  • Park, Ji Hyoung;Kong, Dong Soo;Min, Kyung Sok
    • Journal of Korean Society on Water Environment
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    • v.23 no.6
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    • pp.913-919
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    • 2007
  • This study was conducted to develop a model equation to estimate the delivered point and nonpoint pollutant loads, which are critical factor to determine the water quality of watersheds. The model equation was developed by considering various factors such as biological removal and delivered distance of pollutants, basin shape and geomorphic runoff condition. The parameters for the model equation were estimated in 3 periods, which are October to March, April to June, and July to September. As a parameter, ${\alpha}_p$, ${\alpha}_n$, ${\beta}$, a and b for $BOD_5$-delivered pollutant loads were estimated to be 0.010~0.0155, 0.051, -0.033, 0.018~0.050 and 0.93, respectively. For T-N, ${\alpha}_p$, ${\alpha}_n$, ${\beta}$ a and b were estimated to be 0.0060~0.0140, 0.014, -0.02, 0.044~0.079 and 0.93, respectively. The same parameters for T-P were estimated to be 0.0160, 0.014, -0.0250, 0.015 and 1.21, respectively. The relationship, $E^2$ (Model efficiency), between observed and calculated delivered pollutant loads showed 0.65 for $BOD_5$, 0.81 for T-N, and 0.66 for T-P, respectively. Consequently, the model equation is effective to estimate delivered pollutant loads for TMDL.

Reliability-Based Structural Integrity Assessment of Wall-Thinned Pipes Using Partial Safety Factor (부분안전계수를 이용한 감육배관의 신뢰도 기반 건전성 평가)

  • Lee, Jae-Bin;Huh, Nam-Su;Park, Chi-Yong
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.22 no.3_1spc
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    • pp.518-524
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    • 2013
  • Recently, probabilistic assessments of nuclear power plant components have generated interest in the nuclear industries, either for the efficient inspection and maintenance of older nuclear plants or for improving the safety and cost-effective design of newly constructed nuclear plants. In the present paper, the partial safety factor (PSF) of wall-thinned nuclear piping is evaluated based on a reliability index method, from which the effect of each statistical variable (assessment parameter) on a certain target probability is evaluated. In order to calculate the PSF of a wall-thinned pipe, a limit state function based on the load and resistance factor design (LRFD) concept is first constructed. As for the reliability assessment method, both the advanced first-order second moment (AFOSM) method and second-order reliability method (SORM) are employed to determine the PSF of each probabilistic variable. The present results can be used for developing maintenance strategies considering the priorities of input variables for structural integrity assessments of wall-thinned piping, and this PSF concept can also be applied to the optimal design of the components of newly constructed plants considering the target reliability levels.

Real-Time Estimation of Yaw Moment of Inertia of a Travelling Heavy Duty Truck (주행하는 대형 트럭의 요관성모멘트 실시간 추정)

  • Lee, Seung-Yong;Nakano, Kimihiko;Kim, Se-Kwang
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.41 no.3
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    • pp.205-211
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    • 2017
  • To achieve an advanced control of automobiles, it is necessary to acquire the values of the parameters of a vehicle in real time to conduct precise vehicle control practices such as automatic platooning control. Vehicle control is especially required in controlling trucks, as the mass and inertia change widely according to the loading conditions. Thereafter, we propose to estimate the yaw moment of inertia of the truck in real-time during travelling, by applying the dual Kalman filter algorithm, which estimates the state variables and values of the parameters simultaneously in real-time. The simulation results show that the proposed method is effective for the estimation, which uses commercial software for simulating and analyzing the vehicle dynamics.

Evaluation of Corrosion Fatigue Characteristics of 12Cr Steel Using Backward Radiated Ultrasound (후방복사된 초음파를 이용한 12Cr강 부식 피로특성 평가)

  • Kwon, Sung-Duk;Yoon, Seok-Soo;Song, Sung-Jin;Bae, Dong-Ho
    • Journal of the Korean Society for Nondestructive Testing
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    • v.20 no.5
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    • pp.397-401
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    • 2000
  • The corrosion-fatigue characteristics of the 12Cr steel, which is widely used in fossil power plants as a turbine blade material, are evaluated nondestructively by use of the Rayleigh surface wave. In this study, the frequency dependency of the Rayleigh surface wave is investigated indirectly by measuring the angular dependency of the backward radiation of the incident ultrasonic wave in the aged specimens, and then compared to the corrosion-fatigue characteristics. The width of the backward radiation profile decreases as the increase of the aging temperature, which seems to result from the increase of the effective degrading layer thickness. This parameter also shows an inversely proportionality to the exponent, m, in the Paris law which predicts the crack size increasement due to fatigue. The result observed in this study demonstrates high potential of the backward radiated ultrasound as a tool for the nondestructive evaluation of the corrosion-fatigue characteristics of the aged materials.

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Acoustic Outcomes After Laryngomicrosurgery for Reinke's Edema (라인케 부종에서 후두미세수술 후의 음성 결과)

  • Kim, Min Song;Song, Chang Myeon;Kim, Keon Ho;Jung, Seon Min;Ji, Yong Bae;Tae, Kyung
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.28 no.2
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    • pp.96-99
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    • 2017
  • Background and Objectives : The management of Reinke's edema includes usually medical treatment and voice therapy. Laryngomicrosurgery (LMS) is also necessary, especially to improve airway obstruction. However, voice outcome after LMS has not been determined well. The aim of this study was to evaluate effectiveness of LMS for Reinke's edema and analyze the voice outcomes after LMS. Materials and Methods : Twenty-five patients with Reinke's edema who underwent LMS from September 2007 to December 2016 were enrolled in this study. We analyzed reflux finding score (RFS), reflux symptom index (RSI), and acoustic parameters before and after surgery. Results : Male was 15 (60%) and female was 10 (40%), and mean age was 49.6 years. Preoperative mean value of RFS decreased significantly up to 3 months after LMS ($18.3{\pm}2.2$ and $10.0{\pm}2.2$ at preoperative and 3 months postoperatively, respectively). The mean value of Jitter decreased significantly before and after surgery ($2.71{\pm}2.81%$ and $1.06{\pm}1.21%$ before and after LMS, p=0.041). The mean value of Shimmer also decreased significantly before and after surgery ($7.97{\pm}3.63%$ and $4.83{\pm}1.85%$, respectively, p=0.006). Conclusion : LMS is effective in the treatment of Reinke's edema. It results in favorable acoustic outcomes and laryngoscopic findings in properly selected patients.

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Safety Assessment on the Human Intrusion Scenarios of Near Surface Disposal Facility for Low and Very Low Level Radioactive Waste (저준위 및 극저준위 방사성폐기물 표층처분시설의 인간침입 시나리오 안전평가에 대한 고찰)

  • Hong, Sung-Wook;Park, Sangho;Park, Jin Beak
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.14 no.1
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    • pp.79-90
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    • 2016
  • The second-stage near surface disposal facility for low and very low level radioactive waste's permanent disposal is to be built. During the institutional control period, the inadvertent intrusion of the general public is limited. But after the institutional control period, the access to the general public is not restricted. Therefore human who has purpose of residence and resource exploration can intrude the disposal facility. In this case, radioactive effects to the intruder should be limited within regulatory dose limits. This study conducted the safety assessment of human intrusion on the second-stage surface disposal facility through drilling and post drilling scenario. Results of drilling and post drilling scenario were satisfied with regulatory dose limits. The result showed that post-drilling scenario was more significant than drilling scenario. According to the human intrusion time and behavior after the closure of the facility, dominant radionuclide contributing to the intruder was different. Sensitivity analyses on the parameters about the human behavior were also satisfied with regulatory dose limits. Especially, manual redistribution factor was the most sensitive parameter on exposure dose. A loading plan of spent filter waste and dry active waste was more effective than a loading plan of spent filter waste and other wastes for the radiological point of view. These results can be expected to provide both robustness and defense in depth for the development of safety case further.

Visual Analysis for Detection and Quantification of Pseudomonas cichorii Disease Severity in Tomato Plants

  • Rajendran, Dhinesh Kumar;Park, Eunsoo;Nagendran, Rajalingam;Hung, Nguyen Bao;Cho, Byoung-Kwan;Kim, Kyung-Hwan;Lee, Yong Hoon
    • The Plant Pathology Journal
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    • v.32 no.4
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    • pp.300-310
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    • 2016
  • Pathogen infection in plants induces complex responses ranging from gene expression to metabolic processes in infected plants. In spite of many studies on biotic stress-related changes in host plants, little is known about the metabolic and phenotypic responses of the host plants to Pseudomonas cichorii infection based on image-based analysis. To investigate alterations in tomato plants according to disease severity, we inoculated plants with different cell densities of P. cichorii using dipping and syringe infiltration methods. High-dose inocula (${\geq}10^6cfu/ml$) induced evident necrotic lesions within one day that corresponded to bacterial growth in the infected tissues. Among the chlorophyll fluorescence parameters analyzed, changes in quantum yield of PSII (${\Phi}PSII$) and non-photochemical quenching (NPQ) preceded the appearance of visible symptoms, but maximum quantum efficiency of PSII ($F_v/F_m$) was altered well after symptom development. Visible/near infrared and chlorophyll fluorescence hyperspectral images detected changes before symptom appearance at low-density inoculation. The results of this study indicate that the P. cichorii infection severity can be detected by chlorophyll fluorescence assay and hyperspectral images prior to the onset of visible symptoms, indicating the feasibility of early detection of diseases. However, to detect disease development by hyperspectral imaging, more detailed protocols and analyses are necessary. Taken together, change in chlorophyll fluorescence is a good parameter for early detection of P. cichorii infection in tomato plants. In addition, image-based visualization of infection severity before visual damage appearance will contribute to effective management of plant diseases.

Development of the DVH management software for the biologically-guided evaluation of radiotherapy plan

  • Kim, Bo-Kyong;Park, Hee-Chul;Oh, Dong-Ryul;Shin, Eun-Hyuk;Ahn, Yong-Chan;Kim, Jin-Sung;Han, Young-Yih
    • Radiation Oncology Journal
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    • v.30 no.1
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    • pp.43-48
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    • 2012
  • Purpose: To develop the dose volume histogram (DVH) management software which guides the evaluation of radiotherapy (RT) plan of a new case according to the biological consequences of the DVHs from the previously treated patients. Materials and Methods: We determined the radiation pneumonitis (RP) as an biological response parameter in order to develop DVH management software. We retrospectively reviewed the medical records of lung cancer patients treated with curative 3-dimensional conformal radiation therapy (3D-CRT). The biological event was defined as RP of the Radiation Therapy Oncology Group (RTOG) grade III or more. Results: The DVH management software consisted of three parts (pre-existing DVH database, graphical tool, and $Pinnacle^3$ script). The pre-existing DVH data were retrieved from 128 patients. RP events were tagged to the specific DVH data through retrospective review of patients' medical records. The graphical tool was developed to present the complication histogram derived from the preexisting database (DVH and RP) and was implemented into the radiation treatment planning (RTP) system, $Pinnacle^3$ v8.0 (Phillips Healthcare). The software was designed for the pre-existing database to be updated easily by tagging the specific DVH data with the new incidence of RP events at the time of patients' follow-up. Conclusion: We developed the DVH management software as an effective tool to incorporate the phenomenological consequences derived from the pre-existing database in the evaluation of a new RT plan. It can be used not only for lung cancer patients but also for the other disease site with different toxicity parameters.

Effects of Cloud Point of Non-ionic Surfactant on Deinking Efficiency of ONP at High Blending Ratio of OMG (비이온성 계면활성제의 운점이 OMG 배합비가 증가된 폐 신문지 탈묵효율에 미치는 영향)

  • Lee, Tai Ju;Seo, Jin Ho;Ryu, Jeong Yong
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.47 no.6
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    • pp.164-169
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    • 2015
  • Nowadays blending ratio of OMG (old magazine) in recovered paper used for manufacturing newspaper have been increased. When large amount of OMG is consumed in newsprint mill, brightness can be improved by inorganic pigments of coating layer. On the other hand decrease in yield of deinking process will be encountered because the pigments can be removed as reject of froth flotation process. Therefore selection of the optimal deinking agent is an important. Non-ionic surfactant have been used widely in newsprint mill. Non-ionic surfactant has amphoteric characteristics. Hydrophilic group is ethylene and propylene oxide that can induce hydrogen bonding with water molecules. In this regard, cloud point is an important parameter in order to control efficiency of deinking process because hydration of the hydrophobic group can be varied according to temperature of a system. In this study, deinking properties of ONP at high blending ratio of OMG was analyzed according to cloud points of non-ionic surfactants. $L^*$, $a^*$, $b^*$, brightness and effective residual ink concentration did not affected by the change of cloud points. Especially, flotation reject decreased significantly according to increase in cloud point of the non-ionic surfactant. Consequently, when a nonionic surfactant having a cloud point higher than the temperature of the system is used, properties of the deinked pulp can be maintained and yield of deinking process can be improved.

중성빔 식각을 이용한 Metal Gate/High-k Dielectric CMOSFETs의 저 손상 식각공정 개발에 관한 연구

  • Min, Gyeong-Seok;O, Jong-Sik;Kim, Chan-Gyu;Yeom, Geun-Yeong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.287-287
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    • 2011
  • ITRS(international technology roadmap for semiconductors)에 따르면 MOS (metal-oxide-semiconductor)의 CD(critical dimension)가 45 nm node이하로 줄어들면서 poly-Si/SiO2를 대체할 수 있는 poly-Si/metal gate/high-k dielectric이 대두되고 있다. 일반적으로 metal gate를 식각시 정확한 CD를 형성시키기 위해서 plasma를 이용한 RIE(reactive ion etching)를 사용하고 있지만 PIDs(plasma induced damages)의 하나인 PICD(plasma induced charging damage)의 발생이 문제가 되고 있다. PICD의 원인으로 plasma의 non-uniform으로 locally imbalanced한 ion과 electron이 PICC(plasma induced charging current)를 gate oxide에 발생시켜 gate oxide의 interface에 trap을 형성시키므로 그 결과 소자 특성 저하가 보고되고 있다. 그러므로 본 연구에서는 이에 차세대 MOS의 metal gate의 식각공정에 HDP(high density plasma)의 ICP(inductively coupled plasma) source를 이용한 중성빔 시스템을 사용하여 PICD를 줄일 수 있는 새로운 식각 공정에 대한 연구를 하였다. 식각공정조건으로 gas는 HBr 12 sccm (80%)와 Cl2 3 sccm (20%)와 power는 300 w를 사용하였고 200 eV의 에너지로 식각공정시 TEM(transmission electron microscopy)으로 TiN의 anisotropic한 형상을 볼 수 있었고 100 eV 이하의 에너지로 식각공정시 하부층인 HfO2와 높은 etch selectivity로 etch stop을 시킬 수 있었다. 실제 공정을 MOS의 metal gate에 적용시켜 metal gate/high-k dielectric CMOSFETs의 NCSU(North Carolina State University) CVC model로 effective electric field electron mobility를 구한 결과 electorn mobility의 증가를 볼 수 있었고 또한 mos parameter인 transconductance (Gm)의 증가를 볼 수 있었다. 그 원인으로 CP(Charge pumping) 1MHz로 gate oxide의 inteface의 분석 결과 이러한 결과가 gate oxide의 interface trap양의 감소로 개선으로 기인함을 확인할 수 있었다.

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