리튬-이온 배터리에 적용된 접착력과 안정성이 향상된 탄소나노월에 관한 연구

김철수(Chulsoo Kim),이석원(Seokwon Lee),Tran Thi May,김강민(Kangmin Kim),안채현(Chaehyun Ahn),심영진(Youngjin Shim),신규리(Kyuri Shin),김정현(Junghyun Kim),김형진(Hyungjin Kim),최원석(Wonseok Choi) 대한전기학회 2022 대한전기학회 학술대회 논문집 Vol.2022 No.7

Effect of Co-Opted Board on Audit Fees

Chaehyun Kim(김채현),Eunsuh Lee(이은서),Junyoup Lee(이준엽) 한국국제회계학회 2020 국제회계연구 Vol.0 No.89

본 연구는 코옵티드(co-opted)이사가 감사품질로 대변되는 감사보수에 미치는 영향을 분석한다. Coles et al. (2014)는 코옵티드 이사를 최고경영자의 임기가 시작된 이후에 임명된 이사로 정의하였다. 코옵티드 이사를 측정하기 위해 첫째, 코옵티드 이사가 전체 이사회에 차지하는 비율과 둘째, 전체 코옵티드 이사들의 임기가 전체 이사들의 임기에 차지하는 비율을 이용하였다(Coles et al. 2014). Withisuphakorn and Jiraporn (2017)과 Huang et al. (2019)은 코옵티드 이사가 이사회의 모니터링 기능을 낮추는 경향이 있다고 주장하였다. 지금까지 선행연구는 이사회의 모니터링 기능의 강화는 감사품질을 높여 궁극적으로 감사보수를 높인다고 하였다. 따라서 코옵티드 이사는 감사품질에 음(-)의 영향을 줄 것이고, 이는 궁극적으로 감사보수를 낮출 것으로 예상할 수 있다. 본 연구가설 검증을 위해 2000년-2013년 분석대상기간 동안 미국에 상장된 기업을 대상으로 하였다. 실증분석 결과, 코옵티드 이사와 감사보수는 음(-)의 관계가 있는 것으로 나타나, 코옵티드 이사는 감사품질을 낮추는 것으로 나타났다. 추가분석으로는 사내 코옵티드 이사와 사외 코옵티드 이사는 감사품질에 각각 다른 영향을 미치는 것으로 밝혀져 코옵티드 이사의 구성이 감사품질에 중요한 역할을 하는 것을 확인하였다. 본 연구는 이사회 구성 및 모니터링 기능이 감사보수에 미치는 영향을 검증하여 최적의 이사회의 구성을 예측하고자 하였으며 이는 향후 정책의 실행에 유용한 시사점을 제공할 것으로 보인다. In this study, we examine the effect of co-opted board on audit fees (as a proxy for audit quality), wherein the board comprises directors who are appointed after the CEO assumes office. We use two measures developed by Coles et al. (2014) to calculate the co-opted board. First, we use CO-OPTION, which is the proportion of the board size comprising the co-opted board. Second, we use TW CO-OPTION, which is the sum of co-opted directors’ tenure divided by the sum of all directors’ tenure. Using a sample of 9,592 firm-year observations in the United States for the period 2000 to 2013, we find that having a high proportion of co-opted board members leads to a decrease in audit quality. This is reflected in the negative relationship between co-opted board and audit fees. This evidence is consistent with the notion that board composition and the effectiveness of board monitoring play significant roles in determining audit fees. Overall, our results are consistent with those of prior studies that co-opted board imposes weak monitoring. In addition, our study contributes to the auditing literature by showing how board composition and monitoring effectiveness influence audit fees.

Relationships to Healing of Connections in Sarah Ruhl’s Dead Man’s Cell Phone

Kim Chaehyun(김채현) 새한영어영문학회 2021 새한영어영문학회 학술발표회 논문집 Vol.2021 No.10

This article examines aspects of relationships, connections, transformation, and a healing process in Sarah Ruhl’s Dead Man’s Cell Phone. Sarah Ruhl, one of the most compelling American playwriters today, depicts the world where people decide to transform themselves in a nomadic journey with her own unique lightness and humor. Ruhl’s concept of transformation relates to Michel Maffesoli’s Nomadism theory. According to Maffesoli, a vagabond is a person who craves transformation and seeks to meet others. He or she is also a subject who pursues infinity. Infinity here means the possibility to meet infinite others. Having established relationship with others, vagabonds get out of their fixedness and experience multiplicity of identities. This makes people build up a bond with one another with shared feelings leading their people to healing. In Dead Man’s Cell Phone, the main character, Jean is a vagabond who escapes from her fixed identity and transforms herself to a variable self to each circumstance. She connects with Gordon’s people using his cell phone to comfort their loss after his death. Gordon’s cell phone functions as a magic object that takes her to meeting others. The stories she confabulates to relieve their wounds impress them as they accept her with reciprocity. Jean, as a vagabond, heals others and herself, experiencing multiple identities by breaking free from her own fixedness and stillness.

Does Managerial Entrenchment Managerial Matter in Management Buyouts? Evidence from Classified Evidence Board Provision

Chaehyun Kim,Hyun Lee,Hyeongsop Shim 한국회계정보학회 2017 한국회계정보학회 학술대회발표집 Vol.2017 No.2

Using a sample of 232 U.S. management buyout (MBO) announcements between 1995 and 2013, we examine whether the presence of the classified board provision affects shareholder wealth and form performance around MBOs. Evidence shows that the existence of classified board provision is positively associated with stock returns around the time of the announcements. We examine whether the operational enhancements following MBOs result from the enhancement of corporate governance or the appropriation of private information. After controlling for firm characteristics and self-selection bias, we find that firms with the classified board provision show more pronounced improvements in operating performance in the period between the pre- and post-announcements, which is consistent with the private information hypothesis. Our logistic regression results suggest that the provision is positively associated with CEO turnover in the year following deal cancelations. These finding suggest that entrenched managers have strong incentives to use private information and exploit the undervaluation of their when they make buyout decisions.

Solving an eigenproblem with analyticity of the generating function

Kim U-Rae,Jung Dong-Won,Kim Dohyun,Lee Jungil,Yu Chaehyun 한국물리학회 2021 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.79 No.2

We present a generating-function representation of a vector defined in either Euclidean or Hilbert space with arbitrary dimensions. The generating function is constructed as a power series in a complex variable whose coefficients are the components of a vector. As an application, we employ the generating-function formalism to solve the eigenproblem of a vibrating string loaded with identical beads. The corresponding generating function is an entire function. The requirement of the analyticity of the generating function determines the eigenspectrum all at once. Every component of the eigenvector of the normal mode can be easily extracted from the generating function by making use of the Schläfli integral. This is a unique pedagogical example with which students can have a practical contact with the generating function, contour integration, and normal modes of classical mechanics at the same time. Our formalism can be applied to a physical system involving any eigenvalue problem, especially one having many components, including infinite-dimensional eigenstates.

Generating-function representation for scalar products

Kim U-Rae,Jung Dong-Won,Kim Dohyun,Lee Jungil,Yu Chaehyun 한국물리학회 2021 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.79 No.5

We employ the generating-function representation for an n-dimensional vector in Euclidean or Hilbert space to evaluate scalar products. The generating function is constructed as a power series in a complex variable weighted by the components of a vector. The scalar product is represented by a convolution of the generating functions for the vectors integrated over a closed contour in the complex plane. The analyticity of the generating functions associated with the Laurent theorem reduces the evaluation of the scalar product into counting combinatoric multiplicity factors. As applications, we provide two exemplary computations: the sum of the squares of integers and the normalization of normal modes in a vibrating loaded string. As a byproduct of the latter example, we find a new alternative proof of a famous trigonometric identity that is essential for Fourier analyses.

CEO Pay Slice and Cost Stickiness

Chaehyun Kim(김채현),Eunsuh Lee(이은서),Maria A. Leach-Lopez 한국국제회계학회 2020 국제회계연구 Vol.0 No.91

본 연구는 경영자 보상차이와 원가의 하방경직성 간의 관련성을 실증적으로 분석하고자 한다. 이를 위해 경영자 보상차이의 변수로 Bebchuk et al. (2011)에서 연봉 서열 상위 5위 내 경영진 임금의 총액 중 최고경영자 임금이 차지하는 비중을 이용하였다. Chen et al. (2012)은 대리인비용이 높은곳에서 원가의 하방경직성이 강하게 나타남을 발견하였다. 대리인 이론에 따르면, 최고경영자는 자신의 이익을 극대화하기 위해 의사결정을 수행하는 경향이 있기 때문에 경영자 보상차이가 높아질수록 원가의 하방경직성을 높이는 경향이 있을 것으로 예상된다. 반면에 청지기 이론에 따르면 최고경영자는 이기적이기보다는 오히려 조직지향적인 성향을 가지고, 자신만의 이익을 우선시 하는 대리인이 아니라 조직의 목표달성의 통해 자신의 목적달성을 도모하는 청지기이다 (Davis et al. 1997). 따라서 청지기 이론에 따르면 최고경영자의 영향력이 높아질수록 자신의 이익추구 극대화보다는 주주의 이익을 극대화하는데 노력할 것이므로 원가의 하방경직성이 낮아질 것으로 예상된다. 본 연구가설 검증을 위해 1992년-2019년 분석대상기간 동안 미국에 상장된 기업을 대상으로 하였다. 실증분석 결과는 다음과 같다. 전반적으로, 경영자 보상차이는 원가의 하방경직성을 낮추는 것으로 나타났는데, 이는 청지기 이론을 지지하는 결과로 해석된다. 하지만 경영자 보상차이가 특정한 한계점 (대략 45%의 경영자 보상차이)을 넘어가면 오히려 원가의 하방경직성을 높이는 것으로 나타났는데, 이는 대리인 이론을 지지하는 결과로 해석된다. 추가분석에 의하면 세계 금융위기 이후의 기업 지배구조 구조조정은 경영자 보상차이가 원가의 하방경직성에 미치는 영향을 완화시켜주는 것으로 나타났다. 이는 효과적인 기업지배구조는 최고경영자 영향력을 일정 부분 제어해주는 효과가 있는 것으로 해석된다. 본 연구는 경영자 보상차이가 원가의 하방 경직성에 미치는 영향은 비단조적(nonmonotonic)이며, 이들의 관계를 대리인 이론만이 아닌 청지기 이론으로도 설명하였다는 점에서 그 의의가 있다고 할 수 있다. In this study, we examine the effect of CEO pay slice (CPS) on cost stickiness. By following Bebchuk et al. (2011), we measure CPS as the CEO’s total compensation as a fraction of the combined total compensation of the top five executives. Costs are sticky if the magnitude of costs increase is bigger than the magnitude of costs decrease associated with an equivalent decrease in economic activity (Venieris et al. 2015). Bebchuk et al. (2011) and Chintrakarn et al. (2014) indicate that CPS represents the ability of a CEO to extract rents. According to the agency theory, CPS is likely to increase cost stickiness due to high agency costs. Conversely, the stewardship theory suggests that CPS is likely to reduce cost stickiness because a CEO is not an opportunistic agent, but a good steward (Donaldson and Davis 1991) acting in the best interest of shareholders by setting costs at an optimal level. Using a sample of 34,746 firm-year observations in the United States for the period 1992 to 2019, our results find a nonmonotonic relationship between CPS and cost stickiness. Specifically, relatively low CPS results in less cost stickiness. However, when CPS surpasses a certain point (approximately 45 percent of CPS), cost stickiness dramatically increases. These results are consistent when endogeneity issues are controlled by using propensity score matching regression. Finally, we find that corporate governance restructuring forced by the Global Financial Crisis mitigates the effect of CPS on cost stickiness, emphasizing the importance of implementing effective corporate governance and CEO compensation structure.

Exploring Nonlinear Effects of CEO Power on Stock Price Crash Risk

Chaehyun Kim 한국재무학회 2021 財務硏究 Vol.34 No.3

Heterogeneous Value Creation of Doctoral Independent Directors during Mergers and Acquisitions : Evidence from Target Shareholder Gains

Chaehyun Kim,Hyeongsop Shim 한국재무학회 2016 한국재무학회 학술대회 Vol.2016 No.05

Using manually collected biographical information on independent directors in target firms, we analyze the role of directors with doctoral degrees in mergers and acquisitions between 2005 and 2014. We first observe that doctoral independent directors serve on the boards of about 68% of target firms. We find that the market differently responds to the existence of doctoral independent directors with two distinct disciplines during the M&A announcements. While doctoral directors with business-related backgrounds are negatively associated with shareholder wealth, those with technology-related backgrounds tend to increase shareholder wealth. Interestingly, our empirical results show that doctoral independent directors with business-related degrees improve shareholder wealth in targets with higher advisory needs. We also find that low monitoring intensive targets, which have greater monitoring needs than high monitoring intensive targets, benefit only from independent directors with technology-related degrees. Overall, our findings imply that doctoral independent directors can provide better advisory and monitoring service when their expertise is relevant to the firm’s need.

Co-opted Boards and Stock Price Crash Risk

Chaehyun Kim,Junyoup Lee,Sanggeum Woo 한국재무학회 2018 한국재무학회 학술대회 Vol.2018 No.05

We investigate whether co-opted boards increase future stock price crash risk. Co-opted directors appointed after the CEO assume office tend to have allegiance to the CEO, attenuating board monitoring roles. Using a sample of firms for the period 1996-2014, we find robust evidence that board co-option is positively associated with stock crash risk, suggesting that weak monitoring induced by co-opted directors facilitates managerial bad news hoarding activities. Further analyses show that the impact of co-option on crash risk is more pronounced when the CEO has higher career concerns, as measured by product market competition and age, indicating that the CEO who has greater preferences for bad news hoarding is more likely to exploit opportunities relating to attenuated board monitoring to promote their personal benefits. Overall, our findings suggest that board co-option appears to decrease the effectiveness of board monitoring and the role of board monitoring is particularly important when the CEO has stronger incentives to hoard bad news.