• Applied Chemistry for Engineering
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• v.18 no.5
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• pp.511-515
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• 2007

The yield of oil was rapidly increased at $440^{\circ}C$ compared to $400^{\circ}C$ and $420^{\circ}C$ when the isothermal pyrolysis of waste ship lubricating oil was carried out in tubular type reactor, and pyrolysis was almost finished within 30 min. The yield of gas was decreased depending on the reaction temperature in which that of solid was not much changed. Pyrolysis experiments of waste ship lubricating oil were carried out with used ZSM-5 produced from a petrochemical process. The yield of gas was highly increased in the case of used ZSM-5 and fresh ZSM-5 compared to the case without catalyst. The produced oil and gas were almost constant for fresh ZSM-5 and used ZSM-5 at the same reaction temperature. In the reaction temperature $400{\sim}440^{\circ}C$, the selectivity of $C_5-C_{11}$ was two times higher with fresh ZSM-5 and used ZSM-5 than the case without catalyst.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.1
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• pp.35-42
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• 2014

Recently, in industry field, many researchers are looking for ways to reduce the use of lubricant because of environmental and economical reasons. MQL lubrication is one of many lubrication technologies. The aim of this study is to evaluate the machinability considering lubrication methods and taper angles of workpieces for turning of SCM440. Workpieces of two shapes such as workpiece with and without taper angle are used. And two lubrication methods such as MQL and Wet have been considered. And cutting force and surface roughness are used as characteristic values. Cutting speed, feed rate, injection angle and distance are used as design parameters. The characteristic values were statistically analyzed by Taguchi method. From the results, main effects plot and importance of each parameter according to conditions are analyzed. Finally, this study has been suggested the optimum machining conditions according to the lubrication methods, machining conditions and shape of workpiece.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.440-444
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• 1993

• Bulletin of the Korean Chemical Society
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• v.22 no.5
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• pp.439-440
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• 2001

• IEIE Transactions on Smart Processing and Computing
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• v.5 no.6
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• pp.440-444
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• 2016

In this paper, an equivalent circuit model for near-field noise emission is proposed to implement a multimedia operation-monitoring system for mobile devices. The proposed model includes a magnetic field probe that captures noise emissions from multimedia components, and a transfer function for near-field noise coupling from a transmission line source to a magnetic field probe. The proposed model was empirically verified with transfer function measurements of near-field noise emissions from 10 kHz to 500 MHz. With the proposed model, a magnetic field probe was optimally designed for noise measurement on a camera module and an audio codec in a mobile device. It was demonstrated that the probe successfully captured the near-field noise emissions, depending on the operating conditions of the multimedia components, with enhanced sensitivity from a conventional reference probe.

• Journal of international Conference on Electrical Machines and Systems
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• v.1 no.4
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• pp.440-447
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• 2012

This paper provides essential information on research completed with the aim to develop a 'dc motor test and analysis platform' which can be used to provide dc motor characteristics, calculate losses and efficiency, and also work as a dc motor speed controller. A user can test a given dc motor for these analyses by practicing different conventional methods, but, the concept discussed in this paper, reveals how intelligent integration of all these analyses can be done with a single user friendly automated setup. Integration has been accomplished by a technique that can accommodate all types of dc motors with different ratings at various loading conditions. However, experimentally measured results of a 0.5HP separately excited dc motor using the discussed scheme are presented in the paper. Also, a comparison of the methodology of this system with conventional techniques has also been elaborated on to show the effectiveness of the system.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.4
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• pp.371-381
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• 2020

The failure mode of concrete reinforced with FRP is defined as the concrete crushing and the fiber rupture and the definition of limit state is a slightly different according to the design methods. It is relatively difficult to predict of FRP reinforced concrete because the mechanical properties of fibers are quite depending on its of fibers. The design code by ACI440 committee, which has been developed mainly on GFRP having low modulus of elasticity, is widely used, but the applicability on other FRPs of this code has not been sufficiently verified. In addition, the ultimate and serviceability limit state based on the ACI440 are comparatively difficult to predict the behavior of member with the 0.8~1.2 𝜌_b because crushing and rupturing failure can be occurred simultaneously is in this region of reinforcement ratio, and predicted deflection is too sensitive according to the loading condition. Therefore, in this study, reliability and convenience of the prediction of structural performance by design methods such as ACI440 and MC90 concept, respectively, were examined through the experimental results and literature review of the beam and slab with the reinforcement ratio of 0.8 ~ 1.4. As a result of the analysis, it can be applied to the FRP reinforced structure in the case of the simple moment-curvature formula (LIM-MC) of Model Code, and the limit state design method based on the EC2 is more reliable than the ultimate strength design method.

• Plant Resources
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• v.4 no.3
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• pp.121-129
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• 2001

Intraspecific genetic diversity of sixteen accessions of Mogolian Alliums including fifteen species was investigated using randomly amplified polymorphic DNA (RAPD) analysis. Twenty three out of forty primers revealed scorable polymorphism. A total of 440 RAPD markers were generated on the 16 accessions of Mongolian Alliums. Among 440 RAPDs assayed, 439 were polymorphic with a mean polymorphic rate of 99.7%. Unweighted pair-group method using an arithmetic average (UPGMA) cluster analysis using RAPD data separated the 16 Allium accessions into two broad groups at similarity index 0.70. The clustering of the species was closely related with previous classification between A. altaicum and A. fistulosum. In addition, a high genetic similarity was showed between A. cepa and A. tagar.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.4
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• pp.440-443
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• 2010

This paper deals with the method of vibration measurement of a gun barrel structure using mechanical filter. When a bullet with high speed is moving within a gun barrel type structure with low bending vibration frequencies, it is difficult to measure the bending vibration signals of the structure. For example, noncontact type sensors such as displacement or velocity sensor are not appropriate for the measurement of vibrational signals because of the movement effect of the equipment frame through the moving structures or effect of the ground vibration. One of contact type sensors such as accelerometer is profitable for measurement of vibrational signals because of its wide measurement ranges. In the case of a gun barrel structure including high vibrational signals like shock waves, however, it is necessary to propose vibration measurement method filtering high frequencies. The purpose of the paper is to propose the proper vibrational measurement technique filtering high frequencies of a gun barrel type structure.

• Journal of Chest Surgery
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• v.44 no.6
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• pp.440-443
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• 2011

A glomus tumor is an uncommon soft tissue tumor that is most commonly found in the subungual area and a glomus originating in the trachea is extremely rare. Histologically and ultrastructurally, these tumors have been divided into three subtypes: classic glomus tumors, glomangiomas, and glomangiomyomas. Glomangiomyomas account for less than 10% of all glomus tumors and are the least common type. We report a case of a 54-year-old man with glomangiomyoma of the trachea who presented with stridor. We treated the tumor by segmental resection and primary repair via a transcervical approach.