• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.5
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• pp.1-11
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• 2000

This study is aimed to develop a proto-type LPG engine for medium-duty commercial vehicles in order to substitute for conventional diesel engine. Recently, it is recognized that diesel engines are main cause for smoke pollution in urban site. So, it is expected to reduce this environmental emission by developing and substituting LPG engine which has the advantage of practical use in a short development period in aspects of infrastructures. For that, after analysing the specifications and performance characteristics of a base diesel engine, parts of combustion chamber, intake system, fuel supply and ignition systems suitable for LPG combustion were re-designed and manufactured. And and engine controller for fuel supply and ignition distributions was matched by feedback mapping based on the speed-load conditions. The torque and power of LPG engine were increased by 6∼12% on the overall driving conditions compared to the base diesel engine, and fuel consumption rate marked the similar level based on the fuel price. Exhaust emissions such as THC, CO, NOx recorded the same order with conventional LPG engine for passenger car.

• Journal of the Korean Society for Library and Information Science
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• v.35 no.1
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• pp.123-141
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• 2001

This study is to examine academic phenomena of public administration research field in Korea through analysing the trends of researcher behavior. For the purpose of this study I analysed the types of research performance, reference materials, core journals, and the half-life of reference materials by investigating the articles in Korean Public Administration Review which is one of the major journal in this discipline. The results I found out are the followings: most of researches of the public administration are performed individually by the established academic fellows : researchers show their preference to foreign journals: as for the case of domestic journals, researchers tend to refer the latest issue: the major journal is discriminated from the others by getting a higher points

• Journal of the Korean Society of Propulsion Engineers
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• v.13 no.4
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• pp.1-8
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• 2009

Accumulated slag mass was predicted to estimate accurate performance of kick motor (KM) system. The validation of numerical analysis was performed with mass flow rate measured at the 4th ground test of the KM. The study described here includes the internal flow field of KM at various time steps during burning. Slag mass accumulation was analyzed through the aluminum oxide particle paths to predict slag mass deposition. Numerical analysis to solve both flow field and droplet accumulation was performed with Fluent 6.3 program. Analysing the effects of the acceleration, starting position and diameters of the aluminum oxide particles, total slag mass accumulation was obtained.

• Journal of the Korean Institute of Navigation
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• v.24 no.1
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• pp.23-34
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• 2000

The human error or error involved with human is still the major portion of the causes of marine casualties and attracting a great concern in ship operation. However, there are not so many researches conducted to investigate or develop methodologies for analyzing such causes of human error in maritime industry, which may be caused by the variety of factors affecting the performance of ship operation and the characteristics of human being. This paper aims to study the methodologies used in investigating human factors or errors in maritime field through the investigation of researches performed so far. The methodology for human factors can be usually classified into one of three types; descriptive studies, experimental research and evaluation research. Also there are many different kinds of applied researches for some specific subjects. Prior to the investigation of the root cause of marine accident related with human error, clear concept of the human factors and systematic taxonomy shall be established. Moreover, it is very important considerations in case of casualty inspection on human factors that the inspector on the accident shall have adequate knowledges, understandings on the concept of human factors including the way of research more than those of methodologies and techniques.

• Journal of Broadcast Engineering
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• v.23 no.2
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• pp.218-226
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• 2018

As the number of personal broadcasting contents is rapidly increasing, the demand for a service that provides highlights is growing. A highlight, a collection of interesting scenes, can improve the quality of viewing experience. In this paper, we propose a method to automatically detect highlights using only chat traffic information. We also propose evaluation methods the effectiveness of using chat traffic in highlight detection. We apply the detection algorithm to game broadcasting, which has larger audience, and demonstrate its performance.

• Korean Journal of Applied Biomechanics
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• v.17 no.3
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• pp.95-103
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• 2007

The purpose of this study is Muscle Activity for the Upper Extremity and Morto-Seoinage(Two-handed shoulder throw) according to performance levels and elite judo players (G1) and non-elite judo players, namely university players (G2). To achieve this purpose, three players in G1 whose main special skill was Morote-Seoinage and three university judo players(G2) were selected as comparative group. After analysing this study, conclusions were derived as follows. 1. Muscle activity of musculi membri superious to group of Kuzushi to Tsukuri was the highest in left biceps brachii and right biceps brachii in order. On the other hand, G2 was the highest in left biceps brachii and left flexer carpi randialis in order. 2. Intergral electromyogram of according to the phase showed right triceps 1P of left flexer carpi radialis. G1 and G2 of showed left biceps brachii was the highest in 1P and 2P. As a result, extra training of left flexer carpi radialis and left biceps brachii is needed.

• Nuclear Engineering and Technology
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• v.19 no.3
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• pp.180-185
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• 1987

A computer code, KAFEPA, for analysing in-reactor behavior of a PHWR-fuel rod under reactor normal operating condition was developed. This code, KAFEPA, corresponds to the ELESIM code that was developed for the same purpose by AECL. Even though the KAFEPA originated from the ELESIM, it contains more accurate and theoretical models in comparison with the ELESIM, such as fission gas release model, in-reactor densification model and a new database for neutron flux depression across the radial direction in a fuel pellet. The KAFEPA code was verified by comparing the predictions with 22 measurements of fission product gas release. The predictions of the KAFEPA was well agreed with the experimental data.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.539-542
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• 2006

Many researches about next generation vehicles are trending toward HEV which has better fuel economy than an internal-combustion engine. But existing HEV has some defects at specific running states(eg. highway running It is possible that dual-mode hybrid system overcomes that defects. Mode change parameter, ${\gamma}$ helps to analyse the mode changing of dual mode hybrid and is applied at a numerical analysis on testing the performance. There is an additional constraint when vehicles drive on engine mode. No power assistance of battery applies on engine mode. Because vehicles must be sustained by only engine power while vehicle drives on constant speed mode. At the conclusion of this paper, graphs show the ability of motors that satisfy the equilibrium of the lever system. Designers can roughly determine capacities of the motors, parameters of the lever system by this analysing method.

• Structural Engineering and Mechanics
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• v.78 no.3
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• pp.255-267
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• 2021

The analysis of simply supported single-cell skew-curved reinforced concrete (RC) box-girder bridges is carried out using a finite element based CsiBridge software. The behaviour of skew-curved box-girder bridges can not be anticipated simply by superimposing the individual effects of skewness and curvature, so it becomes important to examine the behaviour of such bridges considering the combined effects of skewness and curvature. A comprehensive parametric study is performed wherein the combined influence of the skew and curve angles is considered to determine the maximum bending moment, maximum shear force, maximum torsional moment and maximum vertical deflection of the bridge girders. The skew angle is varied from 0° to 60° at an interval of 10°, and the curve angle is varied from 0° to 60° at an interval of 12°. The scantly available literature on such bridges focuses mainly on the analysis of skew-curved bridges under dead and point loads. But, the effects of actual loadings may be different, thus, it is considered in the present study. It is found that the performance of these bridges having more curvature can be improved by introducing the skewness. Finally, several equations are deduced in the non-dimensional form for estimating the forces and deflection in the girders of simply supported skew-curved RC box-girder bridges, based upon the results of the straight one. The developed equations may be helpful to the designers in proportioning, analysing, and designing such bridges, as the correlation coefficient is about 0.99.

• International Journal of Computer Science & Network Security
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• v.21 no.9
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• pp.31-40
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• 2021

The increasing number of credit card fraud cases has become a considerable problem since the past decades. This phenomenon is due to the expansion of new technologies, including the increased popularity and volume of online banking transactions and e-commerce. In order to address the problem of credit card fraud detection, a rule-based approach has been widely utilized to detect and guard against fraudulent activities. However, it requires huge computational power and high complexity in defining and building the rule base for pattern matching, in order to precisely identifying the fraud patterns. In addition, it does not come with intelligence and ability in predicting or analysing transaction data in looking for new fraud patterns and strategies. As such, Data Mining and Machine Learning algorithms are proposed to overcome the shortcomings in this paper. The aim of this paper is to highlight the important techniques and methodologies that are employed in fraud detection, while at the same time focusing on the existing literature. Methods such as Artificial Neural Networks (ANNs), Support Vector Machines (SVMs), naïve Bayesian, k-Nearest Neighbour (k-NN), Decision Tree and Frequent Pattern Mining algorithms are reviewed and evaluated for their performance in detecting fraudulent transaction.