• Management & Information Systems Review
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• v.31 no.4
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• pp.469-490
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• 2012

This study reviews the issue of endogeneity which has gained in importance in the empirical accounting researches in recent years. In so doing, I aim to call attention to the extent to which the presence of endogeneity limits the validity of empirical testing of models. More specifically, this paper explains what endogeneity is, its causes and consequences, and potential ways of managing the problem. The issues that concern endogeneity include, in the main, omitted variables, simultaneity, equilibrium conditions, choice variables. In this paper, I also discuss the implications derived from several selected empirical accounting research topics, that explicitly dealt with the problem of endogeneity. These include, among others, Oswald and Zarowin's (2007) study on the informativeness of capitalization of R&D, Hazarika et al. (2012) focusing on the relationship among internal corporate governance, CEO turnover, and earnings management, and a series of literature devoted to the associations between corporate governance structure and firm values. Finally, possible approaches for dealing with endogeneity are discussed.

• Korean Journal of Cognitive Science
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• v.1 no.1
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• pp.145-164
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• 1989

The present paper studies the development of null anaphor,with special attention to whether Korean children's use of null anaphora exhibits the type of directionality preforence predicted by Lust & Mangione(1983)and Lust(1986).If these researchers are correct,anaphora in Korean children's language should be constrained backward since Korean is a left-branching language.That is,it is predicted that Korean chidren would perfer backward anaphora to the forward pattern.For the purpose of this study, ninety-six children were individually tested in an elicited imitation task, twenty-four children from four age groups(4:1-9:7).Three types of constructions,sentences involving a redundant NP,forward patterns of ananphora,and backsward patterns of anaphora were devised.It was discovered that like English speaking children, Korean children prefer forward patterns of anaphora to backward structures.It was thus speculated that the forward preference may well be indedpendent of grammatical factors,reflecting instead processing considerations which favour mention of the referent befor the use of anaphoric elements.

• Proceedings of the Membrane Society of Korea Conference
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• 1998.04a
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• pp.17-20
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• 1998

1. 서론 : 계면중합은 제조에 따른 박막의 성능 조절이 가능한 이유로 해서 역삼투용 복합막의 주요 제조 방법으로 제시되어 왔다. 계면중합을 응용하여 제조된 복합막의 성능은 반응 단량체의 종류, 용재의 종류, 단량체의 농도, 반응시간, 열처리 유무 및 온도와 시간 등에 의해 변한다. 한편 위의 변수에 절대적인 영향을 받고 아울러 단량체간의 몰 비가 성립하지 않음으로 해서 최적의 막 성능으로 제시되는 조건을 만족하기 위하여 주로 시행착오에 의한 방법을 동원하여 여러 변수에 다른 제조 막의 성능 고찰을 실시하여 왔다. (생략)

• Proceedings of the Korea Information Processing Society Conference
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• 2001.04a
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• pp.581-584
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• 2001

오늘날 매우 널리 사용되는 TCP/IP 프로토콜은 많은 보안적 흠을 가지고 있다. 시퀸스 번호를 스푸핑, 소스 번호를 스푸핑, 인증 공격 등 많은 류의 공격이 이런 흠을 통해서 행해지고 있다. 또한 근원적으로 패킷의 TCP헤더 필드의 포트 번호와 IP 헤더 필드의 주소 번호를 분석하여 포트번호와 IP번호를 알아내어 상대방을 공격한다. 이에 상대방으로부터 어드레스 번호를 은닉하거나 생략하여 전송가능하여 상대방이 패킷을 분석하기 어렵게 만들어 TCP/IP 패킷의 정보를 보호하고자 한다. 이에 본 논문은 MPLS 영역에서 IP 패킷의 헤더의 주소 필드 영역을 LER에서 임의의 매핑 변수에 의해 대체함으로써 MPLS 영역에서의 IP 패킷은 IP 주소 번호를 생략할 수 있다. 이에 본 논문에서는 IP 헤더의 Address field를 제거하기위한 LER을 제안하고 LER-to-LER의 메커니즘을 제시한다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.11
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• pp.2721-2726
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• 2014

In a MOG algorithm using the GMM to subtract background, the model parameter computation and the object classification to be performed at every pixel require a huge computation and are the chief obstacles to its uses. This paper proposes a fast MOG algorithm that partly adopts the simple model parameter computation and the object classification skip on the basis of the object prediction. The former is applied to the pixels that gives little effect on the model parameter and the latter is applied to the pixels whose object prediction is firmly trusted. In comparative experiment between the conventional and proposed algorithms using videos, the proposed algorithm carries out the simple model parameter computation and the object classification skip over 77.75% and 92.97%, respectively, nevertheless it retains more than 99.98% and 99.36% in terms of image and moving object-unit average classification accuracies, respectively.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.918-919
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• 2012

This paper present a method of function decomposition and input variable manipulation method based on modular design techniques. We obtain the column multiplicity of decomposition function according to row decomposition method. Also, the proposed partial decomposition function have advantage which is able to omit control function using t-Gate. We find the advantage for internal connection decrement 12% and T-gate number 16%, therefore we find the simple design circuit.

• Journal of KIISE:Software and Applications
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• v.41 no.8
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• pp.598-604
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• 2014

In this paper, we develop stepwise regression data envelopment model to select important variables. We formulate null hypothesis to understand the importance of each variable and use Kruskal-Wallis test for this purpose. If the Kruskal-Wallis test does reject the null hypothesis this will imply there is significant fluctuation in the efficiency score relative to base model. And therefore we have to further check the pair of variables that causes the fluctuation in order to determine its importance using Conover-Inman test. The proposed models helps understand the extent of misclassification decision making units as efficient/inefficient when variables are retained or discarded alongside provides useful managerial prescription to make improvement strategies.

• Environmental and Resource Economics Review
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• v.21 no.2
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• pp.271-299
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• 2012

The relationship between environment and economic growth has been controversial for a long time. The cores of controversy are endogeneity problem and omitted variable bias. This paper tests EKC (Environmental Kuznets Curves) hypothesis by considering econometric issues and estimates the effects of energy mix on $CO_2$ emissions empirically and tests with time series during 1981~2008. By the results of this analysis, we convince EKC Hypothesis which the relationship between $CO_2$ emissions and economic growth is the inverted U-shaped and the national energy mix contributes significantly to GHG mitigation. We also find that the nuclear energy has the greatest contribution for $CO_2$ mitigation and the renewable energy does not seem to contribute little to the $CO_2$ mitigation because the proportion of renewable energy in Korea is negligible. In terms of final energy consumption, $CO_2$ increases and transportation sector is statistically and significantly associated.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.1 s.24
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• pp.11-20
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• 2007

The study proposes the method to cancel the scallop to avoid fracture of the circumstance of the scallop at H shape column-to-beam connection and reinforce at beam flange two faces with the cover plates and rib. A total of four specimens were tested to enhance seismic performance of building structure by reducing the frequency of stress concentration and preventing the brittle fracture of scallop. For this purpose, four full-scale test specimens were made and loaded with quasi-static reversed cyclic loading. The main analytical parameters are panel-zone-strength ratio, yield strengths, initial stiffness, total plastic rotation, contribution of each element to total plastic rotation and energy dissipation capability. For the specimens tested under repeated loading, the experimental result was satisfied with seismic performance requirement as the Special Moment Frames (SMF). The analysis results show that all of the test specimens were found to have good performance to 4% story drift and satisfied the criteria for the plastic roation capacity of SMFs that is 0.03 rad. according to the 1997 AISC seismic provision.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.05a
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• pp.526-529
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• 2003

This paper presents two strategies to refute clock cycles when using stopping rule in VHDL model verification. The first method is that a semi-random variable is defined and the data that stay in the range of semi-random variable are skipped when stopping rule is running. The second one is to keep the old values of parameters when phases are changed. 12 VHDL models are examined to observe the effectiveness of strategies.