• Title/Summary/Keyword: R-449A

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Foramen Magnum Decompression with Duraplasty Using Lyoplant® for Caudal Occipital Malformation Syndrome in a Dog

  • Park, Wan-Sang;Kang, SungHun;Kim, Jun-Su;Park, Sung-Guon;Moon, Hee-Sup;Kim, Sang-yeon;Hong, Sung-Jin;Hwang, Tae-Sung;Lee, Hee-Chun;Hwang, Yong-Hyun;Park, Hyun;Lee, Jae-Hoon
    • Journal of Veterinary Clinics
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    • v.34 no.6
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    • pp.449-453
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    • 2017
  • A 3-year-old castrated male Maltese dog, weighing 4.8 kg was referred with hindlimb ataxia and right forelimb proprioceptive deficits were shown for 20 months. Chiari-like malformation and syringomyelia diagnosed through MRI at a local animal hospital and Knuckling of right forelimb and reluctance to walk were managed with steroid. The medical management was getting ineffective to manage for the symptoms one month before referred. Physical and neurological examinations, radiography, computed tomography, and magnetic resonance imaging were performed and diagnoses of caudal occipital malformation syndrome (COMS) and subsequent syringomyelia (SM) were made. Given that pharmacological treatment was previously ineffective, surgical intervention was recommended. Foramen magnum decompression with duraplasty using $Lyoplant^{(R)}$ was performed. Three days post-surgery, the dog showed improved gait and activity. After 2 months, the dog received no additional prescription medications. At the 12-month follow-up after surgery, the dog showed no clinical problems or recurrences, despite complete cessation of pharmacological treatment. In present report, we applied $Lyoplant^{(R)}$ as a dural graft has been carried out in a dog with COMS. Surgical decompression with $Lyoplant^{(R)}$ was an effective long-term (12-month) treatment for COMS without the need for any pharmacological treatment.

Unidirectional cyclic shearing of sands: Evaluation of three different constitutive models

  • Oscar H. Moreno-Torres;Cristhian Mendoza-Bolanos;Andres Salas-Montoya
    • Geomechanics and Engineering
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    • v.35 no.4
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    • pp.449-464
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    • 2023
  • Advanced nonlinear effective stress constitutive models are started to be frequently used in one-dimensional (1D) and two-dimensional (2D) site response analysis for assessment of porewater generation and liquefaction potential in soft soil deposits. The emphasis of this research is on the assessment of the implementation of this category of models at the element stage. Initially, the performance of a coupled porewater pressure (PWP) and constitutive models were evaluated employing a catalogue of 40 unidirectional cyclic simple shear tests with a variety of relative densities between 35% and 80% and effective vertical stresses between 40 and 80 kPa. The authors evaluated three coupled constitutive models (PDMY02, PM4SAND and PDMY03) using cyclic direct simple shear tests and for decide input parameters used in the model, procedures are recommended. The ability of the coupled model to capture dilation as strength is valuable because the studied models reasonably capture the cyclic performance noted in the experiments and should be utilized to conduct effective stress-based 1D and 2D site response analysis. Sandy soils may become softer and liquefy during earthquakes as a result of pore-water pressure (PWP) development, which may have an impact on seismic design and site response. The tested constitutive models are mathematically coupled with a cyclic strain-based PWP generation model and can capture small-strain stiffness and large-strain shear strength. Results show that there are minor discrepancies between measured and computed excess PWP ratios, indicating that the tested constitutive models provide reasonable estimations of PWP increase during cyclic shear (ru) and the banana shape is reproduced in a proper way indicating that dilation and shear- strain behavior is well captured by the models.

Anti-Sway Control of Container Cranes: Inclinometer, Observer, and State Feedback

  • Kim, Yong-Seok;Hong, Keum-Shik;Sul, Seung-Ki
    • International Journal of Control, Automation, and Systems
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    • v.2 no.4
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    • pp.435-449
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    • 2004
  • In this paper, a novel anti-sway control system that uses an inclinometer as a sway sensor is investigated. The inclinometer, when compared with a vision system, is very cheap, durable, and easy to maintain, while providing almost the same performance. A number of observers to estimate the angular velocity of the load and the trolley velocity are presented. A state feedback controller with an integrator is designed. After a time-scale analysis, a 1/4-size pilot crane of a rail-mounted quayside crane was constructed. The performance of the proposed control system was verified with a real rubber-tired gantry crane at a container terminal as well as with the constructed pilot crane. Experimental results are provided.

A comparative study for adsorption of carbolic acid by synthetic resins

  • Uslu, Hasan;Bamufleh, Hisham S.
    • Membrane and Water Treatment
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    • v.6 no.6
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    • pp.439-449
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    • 2015
  • Carbolic Acid which is called phenol is one of the important starting and/or intermediate materials in various industrial processes. However, its excessive release into environment poses a threat to living organisms, as it is a highly carcinogens and hazardous pollutant even at the very low concentration. Thus removal of phenol from polluted environments is very crucial for sustainable remediation process. We developed a low cost adsorption method for separating phenol from a model aqueous solution. The phenol adsorption was studied using two adsorbents i.e., Amber lite XAD-16 and Amber lite XAD-7 HP with a constant amount of resin 0.1 g at varying aqueous phenol concentrations ($50-200mgL^{-1}$) at room temperature. We compared the efficacy of two phenol adsorbents for removing higher phenol concentrations from the media. We investigated equilibrium and kinetics studies of phenol adsorption employing Freundlich, Temkin and Langmuir isotherms. Amberlite XAD-16 performed better than Amberlite XAD-7 HP in terms of phenol removal efficiency that amounted to 95.52%. Pseudo second order model was highly fitted for both of the adsorption systems. The coefficient of determination ($R^2$) with Langmuir isotherm was found to be 0.98 for Amberlite XAD-7 HP. However, Freundlich isotherm showed $R^2$ value of 0.95 for Amberlite XAD-16, indicating that both isotherms could be described for the isotherms on XAD-7 HP and Amberlite XAD-16, respectively.

Development of New Monitoring System for Power Quality Management (새로운 전기품질 감시장치 개발 및 전기품질 관리방안)

  • Nam, Kee-Young;Choi, Sang-Bong;Ryoo, Hee-Suk;Lee, Jae-Duck;Jeong, Seong-Hwan;Kim, Dae-Kyung
    • Proceedings of the KIEE Conference
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    • 2005.07a
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    • pp.447-449
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    • 2005
  • Power supply system & environment have been changed according to the universal global electrification, the pursuit of improving productivity and the convenience of life. The various kinds of modem electric facilities and almost of all kinds of digital devices embedded microprocessor are very sensitive to the supplied power quality variations. So, they are stopped and result in large economic damage when even the deterioration of power quality with short duration is occurred, which was not so fatal to the conventional industrial facilities and devices. Conversely, those facilities and digital devices generate many kinds of power quality problems such as harmonic.;, flicker, voltage drop, etc. This paper presents the status of power quality and outlines the development of a new power quality monitoring system based on the experience of a series of authors' researches and field measurements for industrial customers in Korea. It also proposes the functions of the monitoring device and the efficient analysis method based on the Korean electrical act and international standards on power quality. Finally, the authors suggest some countermeasures for advancing the power quality to cope with the competitive electric power market and customers' needs after domestic restructuring of electric power industry.

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A Numerical Study on the Factors of the Flow Hunting in a Orifice Meter (오리피스 유량계의 유동헌팅 영향인자에 관한 전산유체역학적 연구)

  • Shin, Chang-Hoon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.36 no.4
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    • pp.449-455
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    • 2012
  • During the measurement of the flow rate of gases such as natural gas, flow hunting is observed in most orifice meters but the intensity of flow hunting at each metering system shows different characteristics. In order to investigate why such a difference occurs and whether the difference actually influences metering error, pipeline network analysis on the main factors and characteristics of flow hunting was carried out in a previous study. Following this, in this study, computational fluid dynamics (CFD) analysis was carried out to clarify the relation between flow instability and flow hunting and determine the factors influencing the orifice meter depending on the intensity of upward pressure fluctuation, time interval, and flow rate. Finally, we showed that the pressure hunting rate is a function of the ratio of the pressure difference before and after an orifice meter. On the basis of CFD analysis results, we also presented some major factors and relations influencing flow hunting.

Improvement of Atmospheric Dispersion Model Performance by Pretreatment of Dispersion Coefficients (분산계수의 전처리에 의한 대기분산모델 성능의 개선)

  • Park, Ok-Hyun;Kim, Gyung-Soo
    • Journal of Korean Society for Atmospheric Environment
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    • v.23 no.4
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    • pp.449-456
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    • 2007
  • Dispersion coefficient preprocessing schemes have been examined to improve plume dispersion model performance in complex coastal areas. The performances of various schemes for constructing the sigma correction order were evaluated through estimations of statistical measures, such as bias, gross error, R, FB, NMSE, within FAC2, MG, VG, IOA, UAPC and MRE. This was undertaken for the results of dispersion modeling, which applied each scheme. Environmental factors such as sampling time, surface roughness, plume rising, plume height and terrain rolling were considered in this study. Gaussian plume dispersion model was used to calculate 1 hr $SO_2$ concentration 4 km downwind from a power plant in Boryeung coastal area. Here, measured data for January to December of 2002 were obtained so that modelling results could be compared. To compare the performances between various schemes, integrated scores of statistical measures were obtained by giving weights for each measure and then summing each score. This was done because each statistical measure has its own function and criteria; as a result, no measure can be taken as a sole index indicative of the performance level for each modeling scheme. The best preprocessing scheme was discerned using the step-wise method. The most significant factor influencing the magnitude of real dispersion coefficients appeared to be sampling time. A second significant factor appeared to be surface roughness, with the rolling terrain being the least significant for elevated sources in a gently rolling terrain. The best sequence of correcting the sigma from P-G scheme was found to be the combination of (1) sampling time, (2) surface roughness, (3) plume rising, (4) plume height, and (5) terrain rolling.

FUZZY GOAL PROGRAMMING FOR MULTIOBJECTIVE TRANSPORTATION PROBLEMS

  • Zangiabadi, M.;Maleki, H.R.
    • Journal of applied mathematics & informatics
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    • v.24 no.1_2
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    • pp.449-460
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    • 2007
  • Several fuzzy approaches can be considered for solving multi-objective transportation problem. This paper presents a fuzzy goal programming approach to determine an optimal compromise solution for the multiobjective transportation problem. We assume that each objective function has a fuzzy goal. Also we assign a special type of nonlinear (hyperbolic) membership function to each objective function to describe each fuzzy goal. The approach focuses on minimizing the negative deviation variables from 1 to obtain a compromise solution of the multiobjective transportation problem. We show that the proposed method and the fuzzy programming method are equivalent. In addition, the proposed approach can be applied to solve other multiobjective mathematical programming problems. A numerical example is given to illustrate the efficiency of the proposed approach.

Theoretical Studies of Solvent Effects on Gas Phase Reactions of Methoxide Ion with Substituted Ethylenes$^\dag$

  • Lee, Ik-Choon;Lee, Bon-Su;Won Jong-Ok
    • Bulletin of the Korean Chemical Society
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    • v.8 no.6
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    • pp.444-449
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    • 1987
  • Solvent effects on gas phase reactions of methoxide ion with substituted ethylenes, $CH_2$ = CHR where R = CN, CHO and $NO_2$, are investigated theoretically using the AM1 method. Results show that the methoxide approaches in-plane in all reactions, but subsequently rotate out-of-plane to form tetrahedral complexes in additon reactions. All reactions of a bare methoxide are found to be exothermic, the exothermicity being the greatest in the ${\beta}$-addition, in which the excess energy is forced to be contained within the ${\beta}$-adduct rendering extreme instability. However a part of the excess energy can be removed by a solvate molecule giving a stable complex prior to the product formation. The hydride transfer processes were found to be unfavorable due to the high activation barriers. The ${\alpha}-H^+$ abstraction process from acrylonitrile becomes endothermic as a result of monosolvation of the methoxide, in agreement with experimental results.

A study on modified algorithm to operating train simulation of AT feeding systems (전기철도 AT급전계통의 열차 운형 모의 해석 알고리즘 연구)

  • Choo, Dong-Woog;Kim, Jae-Chul;Jung, Yong-Chul;Jun, Yong-Ju;Lim, Seong-Jeong
    • Proceedings of the KIEE Conference
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    • 2001.04a
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    • pp.449-451
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    • 2001
  • This study presents a study on modified algorithm to operating train simulation of AT feeding systems. In this study equivalent impedance is constructed by $Z_c,\;Z_r,\;Z_f,\;Z_{cr},\;Z_{rf},\;Z_{fc}$. The train current flows through the all auto-transformer corresponding to track impedance. To calculate train voltage from analyzing the railway systems, the algorithm is based on the K. C. L, K. V. L, superposition and circuit separation method. Multi-train's voltages are determined by calculating the catenary voltage at each train's position and adding up these train's voltage drop. Case studies use a field operational data, show that the proposed method is easily applied.

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