기술특례상장기업을 대상으로 투자자의 비합리적인 심리지수와 합리적인 심리지수가 장기성과에 미치는 영향에 관한 연구

김성신 아시아.유럽미래학회 2022 유라시아연구 Vol.19 No.4

The study analyzed whether abnormalities in stock prices that occur after initial public offering can be explained by investor sentiment indexes for technology-specific listed companies and general listed companies. In this regard, the investor sentiment index was classified into an unexplained irrational part and a rational part based on economic fundamental. The investment sentiment index was orthogonalized with the relative strength index, psychological line index, adjusted turnover rate, and trading volume using Yang and Zhou (2015) methodology, and then new variables were calculated through principal analysis. According to Seok et al. (2019), a new variable was used as a dependent variable, and the macroeconomic environmental factors such as excess return on the stock market, term spread, credit spread, firm size, book to market ratio, and price to earnings per share ratio were analyzed. The estimated residuals and forecasts were used as substitutes for the irrational investment sentiment index and the rational investment sentiment index, respectively. The results of the empirical analysis of this study are as follows. First, according to the test results of the average difference between major variables for technology-specific listed companies, the return on total assets was relatively low, and the debt ratio, public offering amount, one-year turnover rate, and buy-sell imbalance of individual investors for one and two years were high. In terms of long-term performance, the industrial adjusted return for two years was relatively low. Second, according to the results of the generalized least squares regression analysis on long-term performance for one year after IPO, the turnover rate showed a negative (-) relationship except for some models. The public offering price adjustment rate showed a positive (+) relationship with long-term performance in some models, and the stock price fell when individual investors bought excessively. Irrational investor sentiment showed a positive (+) relationship with long-term performance in all models. In the emerging market, it can be seen that the price error phenomenon is not properly corrected due to the lack of smooth arbitrage and short selling. Rational investor sentiment showed a positive (+) relationship with long-term performance because it reflected expectations for the market outlook and information on the company's fundamental. Third, even when it was expanded to long-term performance for two years, irrational investor sentiment maintained a positive (+) relationship with long-term performance and was not confirmed in rational investor sentiment. Return on total assets showed a positive (+) relationship with long-term performance in some models, and investors seem to focus on the company's actual business performance after realizing the wrong belief in listed companies. Looking at the long-term performance of technology-specific listed companies and general listed companies for two years, the decline in the long-term performance of technology-specific listed companies was more serious.

재무정보의 비대칭이 IPO 기업의 생존에 미치는 영향에 관한 연구

김성신 한국자료분석학회 2018 Journal of the Korean Data Analysis Society Vol.20 No.3

We test for the association between information asymmetry for financial reports and delisting of IPO firms in Korea stock market over the period 2000 to 2011 by using discretional accrual measures as proxy for information asymmetry. By using Cox proportional hazard model, this research investigates whether low survival probability after going public is associated with higher information asymmetry in the IPO process. The results are as follows: First, delisted firms are more short-lived after going public and less profitable than survival firms. Second, survival probability after going public is significantly positively related to age and firm size. Firms that list in hot market and have larger information asymmetry in IPO process are more likely to delist. Third, survival probability of IPO firms isn’t significantly related to short run performance but significantly positively related to long run performance. Specifically, firms that have relatively better long-run performance have higher survival probability and lower hazard ratio as compared to firms that have worse long-run performance. 본 연구는 2000년 1월부터 2011년 9월까지 국내 주식시장의 신규 상장기업을 대상으로 기업 공개과정에서 재무보고서의 정보 비대칭이 신규 상장기업의 생존확률에 미치는 영향을 살펴보았다. 재무보고서의 정보 비대칭은 이익조정에 따른 Jones(1991), Dechow et al.(1995), Kothari et al.(2005) 모형의 재량적 발생액을 이용하였다. 본 연구에 대한 실증 결과는 다음과 같다. 첫째, 상장폐지 기업은 생존 기업에 비해 설립일로부터 상장일 까지 소요 기간, 상장 후 생존기간이 상대적으로 짧았으며 수익성도 낮았다. 정보 비대칭의 수위도 상대적으로 높게 나타났으며 기업의 장단기 성과도 부진하였다. 둘째, Cox의 비례위험 모형(1972)을 통한 생존분석에서는 설립일로부터 상장일 까지 소요기간이 길고, 기업규모가 크면 상장폐지 확률은 감소하였다. 또한 핫 마켓에 신규 상장된 기업과 정보 비대칭의 수위가 높은 기업은 상장폐지 확률이 높았다. 셋째, 기업공개 이후 주가의 장단기 성과를 통제하였을 때 단기성과는 상장폐지와 유의적인 관계를 갖고 있지 않으나 60개월 간의 장기성과는 유의적인 음(-)의 관계를 갖고 있었다.

미숙아의 대사 영양학적 측면에서의 생리적 특징

김성신 한국정맥경장영양학회 2016 한국정맥경장영양학회 학술대회집 Vol.2016 No.-

A Study on the Effect of the Fund’s Management Organization on the Risk-taking Strategy 펀드의 운용체제가 위험추구 전략에 미치는 영향에 관한 연구

김성신 한국생산성학회 2022 生産性論集 Vol.36 No.4

This study empirically analyzed the effect of the fund management organizational system (individual and team management) on the fund’s risk-taking strategy for Korean equity funds. Decision-making by organizational systems can be explained by the group shift hypothesis and the diversification of opinion hypothesis. In the group movement hypothesis, the final decision in the team chooses extreme decision-making by collecting the opinions of the most active members, and in the diversification of opinion hypothesis, various opinions are finally decided by mutual agreement, making a less extreme choice. The results of panel regression analysis using the fixed effect model for this are as follows. First, it was confirmed that the fund manager chose a strategy to reduce risk when managing the team, supporting the diversification of opinion hypothesis. Based on the agent problem, increasing the management fee of the fund manager increased the risk of the fund manager. Funds with poor management performance in the past used aggressive risk-taking strategies to make up for their past performance. Second, team funds of large asset management companies are taking a strategy to reduce risk. Third, funds belonging to large asset management companies while team management are in a competitive structure for tournaments independent of other fund managers in the asset management company, so they avoided a risk-taking strategy from a relatively conservative perspective.

물류 무인 운반 시스템의 기술 및 동향

김성신 대한전자공학회 2012 전자공학회지 Vol.39 No.5

기업의 정보비대칭은 IPO 기업의 생존에 영향을 미치는 가

김성신 국제지역학회 2018 국제지역학회 춘계학술대회 Vol.2018 No.-

본 연구는 한국 주식시장에서 기업의 정보 비대칭이 신규 상장기업의 생존확률에 미치는 영향을 살펴보았다. 기업의 정보 비대칭은 이익조정에 따른 재량적 발생액을 이용하여 산출하였다. 실증분석 결과는 다음과 같다. 첫 번째, 상장폐지 기업은 생존 기업에 비해 설립일로부터 상장일 까지 소요 기간, 상장 후 생존기간이 상대적으로 짧았으며 수익성도 낮았다. 재량적 발생액을 근거로 한 정보 비대칭의 수위에서도 높게 나타났으며 기업의 장단기 성과도 상대적으로 부진하였다. 두 번째, Cox의 비례위험 모형(1972)을 통한 생존분석의 결과에 의하면 설립일로부터 상장일 까지 소요기간이 길고, 기업규모가 크면 상장폐지 확률은 감소하였다. 또한 기업공개 시장의 사이클에서 핫마켓에 신규 상장된 기업과 정보 비대칭의 수위가 높은 기업의 경우, 상대적으로 상장폐지 확률이 높게 나타났다. 세 번째, 기업공개 이후 주가의 장단기 성과를 통제하였을 때 단기 성과는 상장폐지와 유의적인 관계를 갖고 있지 않으나 36개월, 60개월 간의 장기성과는 유의적인 음(-)의 관계를 갖고 있었다. 즉, 장기 성과가 좋은 신규 상장기업은 상장폐지 확률이 낮았다.

Erythropoietin Attenuates Brain Injury, Subventricular Zone Expansion, and Sensorimotor Deficits in Hypoxic-Ischemic Neonatal Rats

김성신,이경훈,성동경,심재원,김묘징,Ga Won Jeon,장윤실,박원순 대한의학회 2008 Journal of Korean medical science Vol.23 No.3

The aim of this study was to investigate the effect of erythropoietin (EPO) on histological brain injury, subventricular zone (SVZ) expansion, and sensorimotor function deficits induced by hypoxia-ischemia (HI) in newborn rat pups. Seven-day-old male rat pups were divided into six groups: normoxia control, normoxia EPO, hypoxia control, hypoxia EPO, HI control, and HI EPO group. Sham surgery or HI was performed in all animals. HI was induced by ligation of the right common carotid artery followed by 90 min of hypoxia with 8% oxygen. Recombinant human EPO 3 U/g or saline was administered intraperitoneally, immediately, at 24- and 48-hr after insult. At two weeks after insult, animals were challenged with cylinder-rearing test for evaluating forelimb asymmetry to determine sensorimotor function. All animals were then sacrificed for volumetric analysis of the cerebral hemispheres and the SVZ. The saline-treated HI rats showed marked asymmetry by preferential use of the non-impaired, ipsilateral paw in the cylinder-rearing test. Volumetric analysis of brains revealed significantly decreased preserved ipsilateral hemispheric volume and increased ipsilateral SVZ volume compared with the sham-operated animals. Treatment of EPO significantly improved forelimb asymmetry and preserved ipsilateral hemispheric volume along with decreased expansion of ipsilateral SVZ following HI compared to the saline-treated HI rats. These results support the use of EPO as a candidate drug for treatment of neonatal hypoxic-ischemic brain damage.

Scaffold상에 식립한 사람치주인대섬유모세포를 통한 치주조직공학

김성신,김병옥,박주철,장현선,Kim, Seong Sin,Kim, Byung-Ock,Park, Joo-Cheol,Jang, Hyun-Seon 대한치주과학회 2006 Journal of Periodontal & Implant Science Vol.36 No.3

Human periodontal ligament fibroblasts (hPDLF) are very important for curing the periodontal tissue because they can be differentiated into various cells. A tissue engineering approach using a cell-scaffold is essential for comprehending today's periodontal tissue regeneration procedure. This study examined the possibility of using an acellular dermal matrix as a scaffold for human periodontalligament fibroblast (hPDLF). The hPDLF was isolated from the middle third of the root of periodontally healthy teeth extracted for orthodontic reasons. The cells were cultured in a medium containing Dulbecco's modified Eagle medium supplemented with 10% fetal bovine serum at $37^{\circ}C$ in humidified air with 5% $CO_2$. The acellular dermal matrix(ADM) was provided by the US tissue banks(USA). Second passage cells were used in this study. The hPDLF cells were cultured with the acellular dermal matrix for 2 days, and the dermal matrix cultured by the hPDLF was transferred to a new petri dish and used as the experimental group. The control group was cultured without the acellular dermal matrix, The control and experimental cells were cultured for six weeks. The hPDLF cultured on the acellular dermal matrix was observed by Transmission Electron microscopy (TEM). Electron micrography shows that the hPDLF was proliferated on the acellular dermal matrix. This study suggests that the acellular dermal matrix can be used as a scaffold for hPDLF.

웨이블렛 분석을 이용한 직물의 결함 발견과 검출

김성신,송치권 부산대학교 생산기술연구소 2000 生産技術硏究所論文集 Vol.59 No.-

현재 섬유산업에서 직물의 결함을 찾아내는 방법은 생산공정 후에 사람이 직접 눈으로 하고 있다. 온라인 검사의 장점은 제품의 결함의 발견과 함께 원인을 추론하여 피드백을 이용한 생선 조절 변수를 조절하여 품질을 향상시킬 수 있다. 본 논문은 비전을 이용하여 온라인으로 직물의 결함을 찾아내는 방법에 대해 소개한다. 본 논문에서 비전을 이용하여 온라인으로 직물의 결함을 찾아내는 하드웨어와 소프트웨어 부분으로 구성된 탐진 시스템을 제안한다. 하드웨어 부분은 CCD카메라, 프레임그래버와 조명설비를 사용하였고, 소프트웨어로는 2차원 이미지를 1차원 데이터의 흐름으로 줄이는 가로-세로 스캐닝 루틴 알고리즘을 사용했다. 또한, 결함의 추출을 위하여 웨이블렛 변환에 기초한 SNR(Signal to Noise Ratio)계산방법을 도입하였다. 여러 형태의 결함과 옷감에 대해 실험한 결과, 제안된 시스템이 효과적임을 알 수 있다. This paper introduces a vision-based on-line fabric inspection methodology of woven textile fabrics. Current procedure for determination of fabric defects in the textile industry is performed by human in the off-line stage. The advantage of the on-line inspection system is not only defect defection and identification. but also quality improvement by a feedback control loop to adjust set-points. The proposed inspection system consists of hardware and software components. The hardware components consist of CCD array cameras, a frame grabber and appropriate illumination. The software routines capitalize upon vertical and horizontal scanning algorithms characteristic of a particular defect. The signal to noise ratio (SNR) calculation base? on the results of the wavelet transform Is performed to measure any defeats. The defect declaration is carried out employing SNR and scanning methods. Test results from different types of defeat and different sty1e of fabric demonstrate the effectiveness of the proposed inspection system.

인공지능을 활용한 디지털 트윈 기반 ESS 최적 운영 계획 모델 수립에 관한 연구

김성신,박향아,변길성,김종율 대한전기학회 2022 전기학회논문지 Vol.71 No.6

Recently, due to the digitalization of power systems, the convergence technology of power systems and ICT has become important, and with the development of operational technologies, the importance of intelligent energy management is increasing. The importance of energy management through intelligent operating technology is emerging. In this paper, a digital twin model simulated by empirical simulation was constructed using the empirical ESS measurement data information collected from the power system. An optimal operation plan model for ESS was established by simulating the state and environment of the system in the virtual space of the digital twin similar to the actual system. It aims to improve the stable operation and efficiency of ESS through rapid situational awareness and correct decision-making by applying a data-based machine learning model rather than an existing optimization-based operation model.