粉末活性炭의 表面構造 및 細孔分布에 關한 硏究

高玩錫 단국대학교 대학원 1981 學術論叢 Vol.5 No.-

This research was carried out to study the changes of surface area, yield and pore size distribution with that of principal factors in manufacturing powdered activated carbons for liquid phase from waste of urea resin. The surface area was determined by (BET method) adsorption of nitrogen gas at low temperature. The pore size distribution was determined with an mercury penetration porosimeter while the distribution of pores, The results are summerized as follows; 1. The activation temperature and time, indicated the maximum adsorptivity and largest quality of the specific surface area, are 750℃ and 3hrs. 2. The adsorptivity decreases, if the weight percentages of the activator and the promotor to raw material are over 200 and 100 respectively. 3. The yield is 35-50% in weight and it decreased with the activation temperature and time. 4. On pore Volume, pure urea resin>waste of urea resin>P.V.C. resin. But it is guessed to be different according to the kind of added agents.

The Design of the Selection and Alignment Queries Using Mobile Program (J2ME) for Database Query Optimization

Ko,Wan Suk,Min,Cheon Hong 한국디지털정책학회 2003 학술대회 발표논문집 Vol.2003 No.1

재무제표 구조 개선에 관한 연구 : 국제비교 중심으로

이대선,고완석,유청을,송기신,박성환 서강대학교 경영학연구원 2002 서강경영논총 Vol.13 No.1

Effect of human endogenous retrovirus-K env gene knockout on proliferation of ovarian cancer cells

Ko Eun-Ji,Kim Eun Taeg,Kim Heungyeol,Lee Chul Min,Koh Suk Bong,Eo Wan Kyu,Kim Hongbae,Oh Young Lim,Ock Mee Sun,Kim Ki Hyung,Cha Hee-Jae 한국유전학회 2022 Genes & Genomics Vol.44 No.9

Background: Among various human endogenous retroviruses (HERVs), the HERV-K (HML-2) group has been reported to be highly related to cancer. In pancreatic cancer cells, shRNA-mediated downregulation of HERV-K env RNA decreases cell proliferation and tumor growth through the RAS-ERK-RSK pathway; in colorectal cancer, CRISPR-Cas9 knockout (KO) of the HERV-K env gene affects tumorigenic characteristics through the nupr-1 gene. Objective: The effect of HERV-K env KO has not been studied in ovarian cancer cell lines. In this study, we analyzed the tumorigenic characteristics of ovarian cancer cell lines, including cell proliferation, migration, and invasion, and the expression patterns of related proteins after CRISPR-Cas9 KO of the HERV-K env gene. Methods: The HERV-K env gene KO was achieved using the CRISPR-Cas9 system in ovarian cancer cell lines SKOV3 and OVCAR3. Tumorigenic characteristics including cell proliferation, migration, and invasion were analyzed, and related protein expression was investigated by western blot analysis. Results: The expression of the HERV-K env gene in KO cells was significantly reduced at RNA and protein levels, and tumorigenic characteristics including cell proliferation, migration, and invasion were significantly reduced. In HERV-K env KO SKOV3 cells, the expression of the RB protein was significantly up-regulated and the cyclin B1 protein level was significantly reduced. In contrast, in HERV-K env KO OVCAR3 cells, the level of phospho-RB protein was significantly reduced, but other protein levels were not changed. Conclusion: The results of this study showed that HERV-K env gene KO affects cell proliferation, invasion, and migration of ovarian cells through RB and Cyclin B1 proteins, but the specific regulation pattern can differ by cell line.

Correlation analysis of cancer stem cell marker CD133 and human endogenous retrovirus (HERV)-K env in SKOV3 ovarian cancer cells

Kim Do-Ye,Kim Heungyeol,Ko Eun-Ji,Koh Suk Bong,Kim Hongbae,Lee Ji Young,Lee Chul Min,Eo Wan Kyu,Kim Ki Hyung,Cha Hee-Jae 한국유전학회 2024 Genes & Genomics Vol.46 No.4

Background Human endogenous retrovirus (HERV)-K is a type of retrovirus that is present in the human genome, and its expression is usually silenced in healthy tissues. The precise mechanism by which HERV-K env influences cancer stemness is not fully understood, but it has been suggested that HERV-K env may activate various signaling pathways that promote stemness traits in cancer cells. Objective To establish the connection between HERV-K env expression and cancer stemness in ovarian cancer cells, we carried out correlation analyses between HERV-K env and the cancer stem cell (CSC) marker known as the cluster of differentiation 133 (CD133) gene in SKOV3 ovarian cancer cells. Method To perform correlation analysis between HERV-K env and CSCs, ovarian cancer cells were cultured in a medium designed for cancer stem cell induction. The expression of HERV-K env and CD133 genes was verified using quantitative real-time polymerase chain reaction (RT-qPCR) and Western blot analyses. Additionally, the expression of stemness-related markers, such as OCT-4 and Nanog, was also confirmed using RT-qPCR. Results In the stem cell induction medium, the number of tumorsphere-type SKOV3 cells increased, and the expression of CD133 and HERV-K env genes was up-regulated. Additionally, other stemness-related markers like OCT-4 and Nanog also exhibited increased expression when cultured in the cancer stem cell induction medium. However, when HERV-K env knockout (KO) SKOV3 cells were cultured in the same cancer stem cell induction medium, there was a significant decrease in the number of tumorsphere-type cells compared to mock SKOV3 cells subjected to the same conditions. Furthermore, the expression of CD133, Nanog, and OCT-4 did not show a significant increase in HERV-K env KO SKOV3 cells compared to mock SKOV3 cells cultured in the same cancer stem cell induction medium. Conclusion These findings indicate that the expression of HERV-K env increased in SKOV3 cells when cultured in cancer stem cell induction media, and cancer stem cell induction was inhibited by KO of HERV-K env in SKOV3 cells. These results suggest a strong association between HERV-K env and stemness in SKOV3 ovarian cancer cells. Background Human endogenous retrovirus (HERV)-K is a type of retrovirus that is present in the human genome, and its expression is usually silenced in healthy tissues. The precise mechanism by which HERV-K env influences cancer stemness is not fully understood, but it has been suggested that HERV-K env may activate various signaling pathways that promote stemness traits in cancer cells. Objective To establish the connection between HERV-K env expression and cancer stemness in ovarian cancer cells, we carried out correlation analyses between HERV-K env and the cancer stem cell (CSC) marker known as the cluster of differentiation 133 (CD133) gene in SKOV3 ovarian cancer cells. Method To perform correlation analysis between HERV-K env and CSCs, ovarian cancer cells were cultured in a medium designed for cancer stem cell induction. The expression of HERV-K env and CD133 genes was verified using quantitative real-time polymerase chain reaction (RT-qPCR) and Western blot analyses. Additionally, the expression of stemness-related markers, such as OCT-4 and Nanog, was also confirmed using RT-qPCR. Results In the stem cell induction medium, the number of tumorsphere-type SKOV3 cells increased, and the expression of CD133 and HERV-K env genes was up-regulated. Additionally, other stemness-related markers like OCT-4 and Nanog also exhibited increased expression when cultured in the cancer stem cell induction medium. However, when HERV-K env knockout (KO) SKOV3 cells were cultured in the same cancer stem cell induction medium, there was a significant decrease in the number of tumorsphere-type cells compared to mock SKOV3 cells subjected to the same conditions. Furthermore, the expression of CD133, Nanog, and OCT-4 did not show a significant increase in HERV-K env KO SKOV3 cells compared to mock SKOV3 cells cultured in the same cancer stem cell induction medium. Conclusion These findings indicate that the expression of HERV-K env increased in SKOV3 cells when cultured in cancer stem cell induction media, and cancer stem cell induction was inhibited by KO of HERV-K env in SKOV3 cells. These results suggest a strong association between HERV-K env and stemness in SKOV3 ovarian cancer cells.

Financial Performance of Socially Responsible Investing Fund Firms

Ko, Wan Suk(고완석) 한국국제회계학회 2017 국제회계연구 Vol.0 No.71

기업의 사회적책임(CSR) 활동은 사회적으로 바람직하다는 점에서 장려할만하지만, 그러한 기업이 과연 재무적으로도 바람직한 경영을 해나가고 있는지는 별개의 문제이다. 그것은 관련 기업의 CSR 활동이 현재 및 잠재 고객인 공동체에게 얼마나 긍정적인 이미지와 좋은 평판을 가져다주는지, 그리하여 그것이 결국 CSR 활동에 소비한 기업 자원의 비용을 능가하는 미래 수익의 창출에 기여하는지에 달려 있기 때문이다. 이러한 주제와 관련하여 그간 여러 연구들이 있어 왔으나, CSR 활동 또는 CSR 기업의 정의 방법이 다양한 상황에서, 그 결론들이 일치성을 보여 오지 못하여 왔다. 이러한 배경에서 본 논문은 일정한 사회적 책임 기준을 만족시켜 사회적책임투자(SRI) 펀드에 편입된 기업들의 재무적 성과에 대해 검토하여 그 증거를 보이고자 하였다. 그리하여 이러한 SRI펀드 (편입)기업이 순이익 및 자본시장 측정치라는 두 측정치 면에서 재무적 성과를 여하히 보이는지에 대해 실증적 분석을 하였다. 표본은 2010년부터 2015년까지의 최근 기간 동안 한 SRI 펀드에 편입된 한국의 상장기업으로 하여, SRI펀드 기업들의 ROE나 Tobin’s Q가 그렇지 않은 기업들의 것보다 유의적으로 높음을 발견하였다. 이러한 증거는 SRI펀드 기업들이 사회 경제적 공동체로부터 호감을 받아 현재 및 잠재 투자가들에게 미래 경제적 전망에 대해 긍정적 신호를 보내고 있음을 시사해주고 있다고 할 것이다. While corporate social responsibility (CSR) activities are socially desirable, CSR firms may or may not perform financially well, depending on whether they can convey good corporate image to their customers and financial community, and enhance their revenue enough to cover the expenses resulting from their CSR activities. There have been many studies looking into this issue, with their conclusions being inconclusive where CSR firms are variously defined. This study examines the financial performance of CSR firms, defined as the firms whose stocks are selected into the SRI (Socially Responsible I nvesting) funds. The s tudy empirically t ests whether CSR f irms (SRI f und firms) reveal good financial performance in terms of reported earnings and a market measure, based on a sample of Korean listed firms whose stocks were included in an SRI fund during the period from 2010 to 2015. The study found that SRI fund firms revealed better financial performance than non-SRI fund firms: their ROE and Tobin’s Q are relatively significantly higher. This evidence implies that SRI fund firms draw favor from the social and economic community and signal better economic prospect of SRI firms to the present and potential investors.

한국 공인회계사 시험제도의 개선 : 회계학교수와 현직 공인회계사에 대한 설문조사 기반

고완석 ( Wan Suk Ko ) 한국회계학회 2018 회계저널 Vol.27 No.4

본 연구는 현행 공인회계사 시험제도의 현황, 그리고 선진 및 주변 등 5개국의 공인회계사시험제도 사례를 살펴보고, 문제점의 소지와 개선방안을 모색해 보고자 이루어졌다. 이를 위해 현행 공인회계사 시험의 전반적인 문제점, 최소학점이수제도, 영어시험을 포함한 각 시험과목의 필요성과 적절성에 관한 설문조사를 진행하였다. 또한, 공인회계사시험의 1차 시험 합격자에게 별도의 자격을 부여하는 방안 및 2차례 시험의 간소화와 아울러 3차 인증시험을 실시하는 방안, 그리고 문제은행식 출제방식 도입 등을 제시하여 이에 대해 어느 정도 동의하는지 설문을 하였다. 설문대상자는 크게는 대학의 회계학교수와 현직 공인회계사의 2개 집단이며, 현직 공인회계사는 다시 4대회계법인 소속 및 비소속 공인회계사(Big4 와 non-Big4 CPA)의 두 개 집단으로 나누어 분석하였다. 설문지는 2018년 4월과 6월 사이에 전자식으로 작성, 배포되어, 대학의 회계학교수로부터 81부, Big4 CPA로부터 216부, non-Big4 CPA로부터 59부 등 총 356부를 수집하여 분석하였다. 설문조사 결과는 공인회계사시험 개선에 대해 주요한 시사점을 제공해 주었다. 우선, CPA로서의 자질을 시험제도를 통해 높이려면, 시험문제개선은 경영학전반 기본지식, 영어 등 외국어 구사능력 등보다는, 타인과의 소통능력, 회계환경 변화관련 새로운 지식, 공인회계사로서 윤리의식 등에 초점을 맞추어 이 자질들의 계발과 관련된 지식을 함양할 수 있게 하는 방향으로 나아가야 한다는 것이었다. 또한 시험과목의 조정을 해야 한다면 1차 시험이나 2차 시험에서 우선적으로 어떤 과목이 되어야 할 것인지 시사해 주었고, 1차시럼합격자에 대한 인증제도의 도입이나 문제은행식 출제의 과감한 도입은 긍정적으로 고려해야 할 필요성을 시사해 주었다. The objective of this study is to identify the current and potential problems of Korean CPA Examination and to propose how to improve the examination. For this, a questionnaire survey was conducted regarding the problems of the current CPA examination, minimum credit hour requirement, and the necessity and appropriateness of individual test subjects and English language test. The survey also included the questionnaire about the official accreditation of the applicants’ passing the first phase CPA exam, the introduction of the third phase accreditation test along with the simplification of the second phase exam, and the application of the test bank system. An online survey was conducted of 81 accounting professors and 275 incumbent Big4 and non-Big4 CPAs. The result of the survey produced important implications on CPA exam improvement: Exam questions and subjects should be changed so that they can contribute to fostering the ability to communicate with others, new knowledge of changes in accounting environment, and ethical mind as a CPA, rather than general knowledge of business studies and English proficiency. The result also provides a guide on which test subjects should be adjusted first if the exam subjects are to be changed, and suggests proactive consideration of the introduction of the official accreditation of the first phase exam passers and of the application of the test bank system.

기업의 IFRS 적용 주석공시 사례에 대한 재무전문가의 반응

고완석 ( Wan Suk Ko ) 한국회계학회 2017 회계저널 Vol.26 No.1

IFRS`s (International Financial Reporting Standards) requirements for extensive note disclosure have been recognized as possibly posing a significant challenge for the auditors and users, as welll as the preparers, of the financial statements prepared according to IFRS. Concerns have been raised as to whether the costs to fulfill these requirements pay off, including their possibly producing disclosure overload. This paper investigates the views of financial experts (users, preparers and auditors of financial statements) on whether firms properly identify and understand voluminous note disclosure contents and provide information in the relevant form and substance. It examines note disclosure practices as reported in the K-IFRS financial statements (prepared in accordance with IFRS adopted in Korea) and conducts a survey of financial experts` opinions about the adequacy focusing on the sufficiency and usefulness of the note disclosure in the K-IFRS financial statements. The survey results revealed that the concerns about overload of the IFRS disclosure requirements seem to be exaggerated and anecdotal, but that there is a need to improve some disclosure requirements related to the case disclosures. A majority of the respondents preferred clear and condensed presentation of necessary information without a simple collection of too many detailed items and wanted proper separation of figures and assumptions based on their function for better understanding or analyses.

Option을 고려한 객체지향형 Product Structure 설계

고석완(Suk-Wan Ko),김선호(Sunn-Ho Kim),정석찬(Seok-Chan Jeong) 대한산업공학회 1998 대한산업공학회지 Vol.24 No.3

IFRS 도입에 따른 종업원급여 회계기준 적용 사례: 퇴직급여를 중심으로

고완석 ( Wan Suk Ko ) 한국회계학회 2010 회계저널 Vol.19 No.2