활성슬러지 구성 미생물에 의한 폴리오바이러스의 감소 효과

김태동,최동혁,Kim, Tae-Dong,Choi, Dong-Hyuk 한국환경보건학회 2006 한국환경보건학회지 Vol.32 No.4

The biological wastewater treatment system is known to have an important role in reducing the quantify of enteric virus in water environments. To clarify the roles of activated sludge microbes in decreasing the virus infectivity, the behavior of the virus in bacteria, protozoa, and metazoa was examined by pure or mixed culture system using poliovirus type 1(Lsc, 2ab strain). In the bacterial culture systems, the virus infectivity in the liquid phase decreased by a reversible adsorption of the virus to the bacteria or bacterial flocs. On the other hand, in the protozoa and the metazoa culture systems using T. pyriformis and P. erythrophthalma, respectively, with a variety of bacterial strains as prey, the main virus decrease mechanism of reversible adsorption in early stage was changed to irreversible predation, which was not eluted in this study. The virus decrease was more effective in the P. erythrophthalma culture system, which had high predation and floc forming abilities. However, in the mixed culture system of Z. ramigera and P. erythrophthalma, the more rapid reversible adsorption of virus to Z. ramigera flocs preceded the irreversible predation of P. erythrophthalma.

농연에 의한 드론 수신 전파 감쇠에 관한 연구

김태동(Tae-Dong Kim),염인수(In-Su Yeom) 한국화재소방학회 2021 한국화재소방학회논문지 Vol.35 No.1

본 논문은 농연에 의한 드론 수신 전파 감쇠의 상관성을 분석하였다. 수신되는 신호 감도를 분석하기 위해 스펙트럼 분석기와 지향성 안테나를 적용하였고, 실 화재 감식 훈련장에서 연기 층 진입 전후 각 1 min간 상대적인 평균수신 강도를 측정하였다. 사용된 드론은 2.4 GHz~2.48 GHz에서 동작하며 연기층 집입 전 수신되는 전파강도는 -39.3dBm으로 조정 신호 및 영상데이터 수신이 가능함을 확인하였다. 그러나 연기층에 진입했을 때 전파강도는 -47 dBm으로 낮아져 신호의 차단 현상이 발생하였고, 농연에 의해 약 7.7 dBm (5.9 mW)의 감쇠를 보여 주었으며 전파감쇠에 의해 통신장애가 나타나고 있음을 알 수 있었다. 이를 통해 화재 시 발생하는 농연에 의해 수신되는 전파가 감쇠되며 결과적으로 통신 성능을 열화시켜 드론 운영에 영향을 주고 있음을 확인하였다. The objective of this study is to analyze the effect of smoke obscuration on the signal sensitivity of microwaves receivedfrom a drone. A spectrum analyzer and a directional antenna were employed for analyzing the received signal sensitivityand measuring the mean received power, both before and after the drone entered the smoke layer for one min in the firetraining area. The drone operated in the range of 2.4 GHz to 2.48 GHz. It is found that the received power before enteringthe smoke layer is -39.3 dBm, at which signals and image data can be received. However, upon entering the smoke layer,the received power is reduced to -47 dBm, at which signals and image data cannot be received. Hence, the received powerundergoes an attenuation of approximately 7.7 dBm (5.9 mW) owing to smoke obscuration, which causes communicationoutage. Based on this study, it can be concluded that the received power undergoes attenuation owing to smoke obscurationduring fires. Furthermore, if a communication problem occurs due to microwave attenuation, it affects the drone’s operation.

재무보고 적시성이 기업의 신용평가에 미치는 영향 -감사보고시차를 중심으로-

김태동 ( Tae Dong Kim ),배창현(교신저자) ( Chang Hyun Bae ) 한국회계학회 2016 회계저널 Vol.25 No.3

본 연구는 감사보고시차로 측정된 재무보고 적시성이 다음연도 해당 기업의 신용평가에 어떠한 영향을 미치는지 살펴보는데 목적이 있다. 즉, 재무보고 적시성이 회계정보의 신뢰성과 어떠한 관계를 갖는지 분석하였다. 재무보고 적시성의 대용치(proxy)로 측정되고있는 감사보고시차의 경우, 다른 기업에 비해 길다는 것(다른 기업에 비해 적시성이 낮다는 것)은 외부감사인의 노력이 많이 투입되었다는 증거로 해석될 수 있으며, 이는 기업의 위험이 상대적으로 높다는 것일 수 있다. 하지만, 감사보고시차의 증가가 상대적으로 외부감사인의 노력(시간)이 많이 투입된 결과로써 감사품질의 향상으로 이어진다면 이는 기업의 위험을 감소시킬 수 있는 요인으로 작용될 수 있다. 따라서 이러한 상반된 추론을 분석하기 위해 본 연구에서는 귀무가설 형태로 살펴보았다. 분석결과, t기 감사보고시차(결산일에서 감사보고서일까지의 누적기간)가 길어질수록 t+1기의 신용평가(신용점수)에 부정적인 영향을 미치는 것으로 나타났다. 이는 감사보고시차가 커질수록 기업의 위험이 예상한 수준보다 높다는 것일 수 있기 때문에 증가된 기업위험에 대해 시장에서는 부정적인 평가를 하는 것으로 판단되며, 결과적으로 기업의 입장에서는 재무보고 적시성 향상을 위해 노력해야 함을 본 연구에서는 제시하고 있다. 추가분석 결과를 살펴보면, 감사시차(결산일에서 감사보고서 제출일까지의 누적기간)가 길수록, 외부감사시간이 길수록, t+1기의 신용평가에는 부정적인 영향을 미치는 것으로 나타났다. 아울러, 외국인지분율과 감사보고시차에 대한 상호작용 변수의 경우 통계적으로 유의한 음(-)의 값이 나타났는데, 이는 외국인투자자의 감시기능 역할에 대한 긍정적인 신호(signal)가 재무보고의 적시성 지연에 따른 기업의 위험을 감소시킨 것으로 해석된다. This study examines the relation between credit rating of the firms and Audit Report Lag (ARL), measured as the difference in the timeliness of accounting information. Credit ratings are generally known to be considering all the factors affecting the company``s ability to repay debt that are internal and external factors (management risk, industry risk, business and operating risks, financial risks, affiliation risk, etc.) of firm management (Lee et al. 2007). Koh et al.(2013) find that credit rating is negatively associated with enforcement action or not. This study result implies that credit rating agencies when rating firms consider not only the financial information provided by firms but also the information that might cause enforcement action. Further, credit analysts do negative ratings on real activity earnings management of the firms (Lee and Kim 2011), and there is significant positive relationship between conservatism and KIS credit score (Jeon and Lee 2010). The timeliness of financial reporting is a basic requirement for the information usefulness. Prior studies (Givoly and Palmon 1982; Kim 1996) have used ARL as a proxy for timeliness of accounting information and auditor``s audit effort (Sohn et al. 2013). ARL is the period from the fiscal year-end to the date on which the audit report is released (Ettredge et al. 2006). According to the prior studies, auditors exert more effort into audit procedures when the audit risk is high. Exerting more effort to audit procedures (assume that more audit hours cause to delay in ARL) leads to higher audit quality (Palmrose 1986; Choi 1999; Kwon et al. 2005; Caramanis and Lennox 2008) and longer ARL which then might affect the reliability of financial statements. To sum up, ARL that is longer than any other firms, which means reduced in timeliness compared to other firms, could be interpreted as evidence that auditor exerts more effort (audit hours) in the audit procedure, so the risk of such firm is relatively high. However, if an increase in ARL due to auditor``s more effort (audit hours) in the audit procedure resulted in improvement of audit quality, than it could be a factor that might reduce firm risk. As there are conflicting views, we use the null hypothesis to conduct the empirical analysis of our study. Our sample consists of non-financial firms that are listed in the Korea Exchange (KRX) from 2005 to 2010 and whose fiscal year-end is on December 31. Firms with no financial information in Kis-Value database and with no publicly available data for audit report date in DART System of Korean Financial Supervisory Services are eliminated. We use 1% winsorization to all our research variables to exclude the effect of extreme data on our results. The final sample consists of 3,280 firm-years. KIS credit score is used as the dependent variable in an OLS regression. It is scored using credit valuation model developed by Korea Investors Service (KIS) and composed of 1 to 10 points. For the ratings, more favorable (unfavorable) firms are rated close to 1 point (10 points). We also used credit rating of bonds as our proxy for the robustness of our result, provided by 3 authorized credit rating agencies in Korea (NICE Investors Service Co., Korea Investors Service, Inc. and Korea Ratings). Our empirical results show that longer ARL negatively affects the credit rating of the following year. This finding suggests that longer ARL might mean firm risk higher than the expected level and the market gives a negative assessment to the increased firm risk. As a result, this finding suggests that firms need to exert more effort to improve the timeliness of financial reporting. The result of our supplementary analyses suggests that longer ARL and audit hour negatively affect the credit rating of the following year. This result supports the result of our main analyses thus increase the robustness of our study. Finally, we find that foreign investors positively affect the relationship between ARL and credit score. This may be construed that monitoring role of foreign investors works as a positive signal in the market reducing the firm risk caused by delay in the timeliness of accounting information. In addition to the line of credit rating research, this study suggests that timeliness of accounting information could be a determinant. The results of our study have following implications to firms and investors. To firms, our finding indicates that the improvement of timeliness of accounting information is needed for the betterment of credit ratings of following year. Further, delay in the timeliness of accounting information could negatively affect the credit rating of such firm, thus the investors could use this data as investment information.

Sensitivity Analysis and Optimum Design of Energy Harvesting Suspension System according to Vehicle Driving Conditions

김태동(Tae Dong Kim),김지혜(Ji Hye Kim),김진호(Jin Ho Kim) Korean Society for Precision Engineering 2019 한국정밀공학회지 Vol.36 No.12

In this study, the sensitivity of the power generation effect of the applied linear generator of the energy harvesting suspension system under various input conditions was analyzed. The energy-harvesting suspension generates electric energy through energy harvesting using the road surface vibration energy during driving. Before analyzing the power generation effect, we analyzed the structure of the eight-pole Outer PM (Permanent Magnet) linear generator model using the electromagnetic suspension system to design the efficient generator, PIANO (Process Integration and Design Optimization). The ANSYS MAXWELL program was used to perform electromagnetic simulations of a linear generator model installed inside an energy-harvesting suspension to determine the power generation of the linear generator under various input conditions. The sensitivity of each input variable was compared by comparing the power generation effect of the energy-harvesting suspension device according to road displacement, frequency, and vehicle speed. The sensitivity to the road surface frequency was 1.9451, the sensitivity to the road surface amplitude was 1.0502, and the sensitivity to the vehicle speed was 0.6258. It is confirmed that the maximum sensitivity to the road surface displacement was demonstrated.

특수관계자 거래와 기업의 공시수준

김태동(Tae-Dong Kim),이윤아(Yoona Lee),배창현(Chang-Hyun Bae) 한국경영학회 2016 經營學硏究 Vol.45 No.3

This research focuses on the disclosure patterns of related-party transactions and analyzes the relationship between these transactions and characteristics of companies in terms of disclosure. Because managers often exercise their discretionary powers through related-party transactions, disclosure of these transactions may include useful information for external investors in the form of specific transaction details. However, because the current accounting standards are unclear regarding footnote disclosures in reports containing information about related-party transactions, many users of accounting information have identified differences in disclosure methods in between individual firms. If discretionary accounting choices are allowed, then some managers may disclose only good news favorable to themselves; thus, the transparency and comparability of accounting information will deteriorate. In such cases, it is necessary to monitor and control large transactions between related parties to prevent corrupt practices. However, when this transaction information is arbitrarily hidden, this lack of disclosure increases information asymmetry among interested parties. This study focuses on disclosure patterns and hidden actions that conceal specific information about related-party transactions. We analyze firms’ corporate characteristics and identify factors affecting disclosure about related-party transactions. The empirical findings are as follows. First, we find that disclosure(footnote) quality decreases as the trade volume of related-party transactions increases. Second, in cases of propping, we confirm a significant decrease in the number of disclosures of related-party transactions. Lastly, according to the results of an analysis on differences in disclosure behavior by business groups, a decrease in disclosure associated with related-party transactions is observed in non-large business groups. In conclusion, firms that belong to large business groups and those that engage in propping tend to change their patterns of disclosure according to the manager’s discretionary decision-making. Therefore, in order to reduce information asymmetry in the stock market and improve the quality of accounting information, supervisory authorities must discuss institutional regulations to ensure adequate disclosure levels(quality) and encourage active disclosure. Most former research studies develop their arguments assuming that the nature of transactions causes information asymmetry while ignoring the loophole in the disclosure system of relatedparty transactions. Also, considering that studies on the disclosure standards associated with related-party transactions and the factors influencing disclosure are practically non-existent, this paper provides valuable information about related-party transactions and how the disclosure system fails to address issues related to them. By examining these issues, suggest that the problems related to the market’s biased perception of related-party transactions and the limitations of the information environment can be alleviated by taking complementary measures to improve disclosure standards. Furthermore, while discussion is ongoing about establishment of an effective monitoring system to prevent managers’ opportunistic decisionmaking during disclosure of related-party transactions, this thesis provides a suggested configuration and theoretical implications on the direction of future regulatory policy and oversight of relatedparty transactions through revision of the involved disclosure system.

온라인 강의시청 맥락에서 사용자 주도의 컨트롤제한을 통한 인지된 비통제성이 강의 집중에 미치는 영향

김태동(Tae-dong Kim),민병아(Byoung-a Min),이원욱(Won-ouk Lee),박태준(Tae-joon Park),김태공(Tae-kong Kim),이중엽(Joong-yup Lee),이인성(Inseong Lee),김진우(Jinwoo Kim) 한국HCI학회 2016 한국HCI학회 학술대회 Vol.2016 No.1

본 연구는 심리적반발이론에 근거하여, 온라인 학습서비스의 동영상 강의시청맥락에서 사용자의 시스템 통제권을 제약하는 역발상적인 시스템 요인을 제시하였다. 이를 통해 사용자로 하여금 통제성의 상실감에 대한 인지(인지된 비통제성)가 강의 시청에서의 집중을 유도할 수 있음을 기존 연구에 대한 탐색을 통해 이론적 근거를 들어 가설화 하였고, 실험과 설문을 통해 가설 검증을 위한 데이터를 수집하였으며, 이를 분석, 설정된 가설이 통계적으로 유의미함을 검증하였다. Based on Psychological reactance theory, we presented a creative system feature which could restrict the user`s perceived control. Through this, we had set hypotheses insisting perception of user`s deprived freedom could cause user`s concentration on lecture, also collected data to confirm our hypotheses. Finally, we analyzed the data, so that investigated they are all statistically signified.

해양레저관광산업 활성화 전략에 대한 제 고찰

김태동(Tae-Dong Kim) 한국엔터테인먼트산업학회 2014 한국엔터테인먼트산업학회논문지 Vol.8 No.3

본 연구는 강원도 해양레저관광산업의 여건 분석을 통해 경쟁력을 제고시키는 것이 목적이다. 연구의 주요내용은 해양레저관광산업 여건분석, 국?내외 사례분석, 강원도 해양레저관광산업 활성화 전략 크게 세 부문으로 구성하였다. 여건분석, 사례분석에서 제시된 시사점을 토대로 다음과 같은 전략을 제시하였다. 첫째, 해양레저 관련 교육기관 확충, 둘째 프로그램 개발 및 보급, 셋째 어구 및 어항의 효율적 활용, 넷째 요트서비스업 고도화, 다섯째 해양레저관광 특성화 사업 발굴, 여섯째 해양레저관광산업 정책 추진의 고도화이다. This study is to improve the competitiveness through analyzing the condition of Kwangwondo marine leisure tourism industry. The main points of this study is comprised of three parts: marine leisure tourism industry condition analysis, home and foreign case study, and Kwangwondo marine leisure tourism industry activation. The strategies based on suggestions that were presented from condition analysis and case study were as follow: First, educational institutions related to marine leisure expansion. Second, programs development and spread. Third, efficiently utilize fishing ground and implement. Fourth, yacht industry activation. Fifth, unearth specialized marine leisure tourism industry. Sixth, promotion of marine leisure tourism industry policy.

영유아 보육교사의 다문화효능감 영향요인 연구

김태동(Kim Tae-Dong) 한국영유아보육학회 2011 한국영유아보육학 Vol.0 No.66

본 연구는 보육교사의 일반적 특성, 교육요인, 접촉요인 등이 다문화효능감에 어떠한 영향을 미치는지 규명하는데 있다. 이러한 목적으로 300부의 설문지가 배포되었고, 261부가 분석에 사용되었다. 분석결과, 첫째, 일반적 특성으로 학력, 직급은 다문화효능감에 영향을 주고 있었다. 둘째, 교육요인으로서 연수경험, 학부에서의 수강여부 등이 다문화효능감에 영향을 주었으며, 셋째, 접촉요인으로서는 자원봉사경험, 접촉경험 및 지도경험이 다문화효능감에 영향을 주었다. 본 연구결과를 볼 때, 교육요인이나 접촉요인을 강화하여 보육교사로 하여금 다문화효능감 계발을 유도해야하며, 다른 문화나 인종에 대한 선입관이나 편견 등 바람직하지 않은 요인을 지양함으로서 궁극적으로 다문화가정의 유아들에게 양질의 교육을 도모함을 시사한다. In this study, the general characteristics of child care teachers, educational factors, such as contact factors that affects multicultural efficacy is to examine. For this purpose the 300 questionnaires were distributed and 261 were used for additional analysis. As a result, the general characteristics of the first factor, education and work positions to influence the efficacy were multicultural efficacy. Education as a second factor, training experience, whether as an undergraduate course to influence the efficacy were multicultural efficacy. Contact as a third factor, volunteer experience, the contact experience and the teaching of experience had an impact on multicultural efficacy. The results of this study, educational factor, contact factors that enhance or contact your child get a teacher to encourage cultural development and efficacy, stereotypes and prejudices about other cultures and ethnic factors, such as undesirable and ultimately avoided by children of multicultural families Promoting quality education to suggest that.

시장경제발전과 부동산정책

김태동(Tae Dong Kim),김남두,박헌주 철학연구회 2006 哲學硏究 Vol.0 No.72

당뇨병 유무에 따른 췌장암의 임상 양상

김태동 ( Kim Tae Dong ),오희주 ( O Hui Ju ),김국현 ( Kim Gug Hyeon ),김성목 ( Kim Seong Mog ),김준환 ( Kim Jun Hwan ),장병익 ( Jang Byeong Ig ),김태년 ( Kim Tae Nyeon ),정문관 ( Jeong Mun Gwan ) 대한소화기학회 2004 대한소화기학회지 Vol.43 No.1

Background/Aims: Pancreatic cancer is fatal with a dismal 6-month median survival from diagnosis. Diabetes mellitus is reported to be present up to 33.3 percent of patients with pancreatic cancer. The reason for the high frequency of diabetes is unknown. We studied the prevalence and duration of diabetes in patients with pancreatic cancer and the relationship between the two diseases. Methods: A total of 152 patients with pancreatic cancer diagnosed at Yeungnam University Hospital from January 1999 to December 2001 were enrolled in this study. Clinical features, family history, smoking history, and characteristics of the tumor were compared between diabetic and non-diabetic groups. Results: Among 152 patients with pancreatic cancer, 43 patients (28.3%) had diabetes. In diabetic group, mean age of diagnosis was significantly younger than non- diabetic group (62.0±7.2 vs. 65.0±8.8, p<0.05). Most of the patients with diabetes had non-insulin dependent diabetes mellitus (NIDDM) and did not have family history. Diabetes was diagnosed within 2 years after the diagnosis of pancreatic cancer in 35 patients (74.3%) of the diabetic group. There were no differences in the location and stage of tumor, chief complaints, presence of weight loss, and body mass index between the two groups. Conclusions: Diabetes mellitus occurs frequently in patients with pancreatic cancer and does not influence clinical features of pancreatic cancer. Pancreatic cancer should be suspected in patients with recent onset diabetes, especially in patients without family history of diabetes and with type of NIDDM. (Korean J Gastroenterol 2004;43:35-40)