• Title/Summary/Keyword: 이차분석

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A Study on the Career Development of an Artist: The Case of KAWS (미술가의 경력형성에 관한 연구 - 카우스(KAWS)를 중심으로 -)

  • Lee, Jin Woo
    • Korean Association of Arts Management
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    • no.53
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    • pp.47-69
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    • 2020
  • This paper aims to understand the agents which have an impact upon artists' career development. By critically exploring previous research, this article conceptualizes the roles of intermediaries such as art schools, galleries, critics, and collectors in influencing the careers for artists. The qualitative case study is conducted by selecting KAWS as an intrinsic case. This study collects secondary data about the career trajectory of KAWS by various sources, which are analyzed according to the conceptual framework. The outcome of this research clarifies previous research from a sociological point of view in which highlights the significant importance of the art world's gallery, critics, media and collectors in developing the artist's career. In this paper, more importantly, the public attention to artists is construed as one of the agents influencing the career development of artists.

Power transformation in quasi-likelihood innovations for GARCH volatility (금융 시계열 변동성 추정을 위한 준-우도 이노베이션의 멱변환)

  • Sunah, Chung;Sun Young, Hwang;Sung Duck, Lee
    • The Korean Journal of Applied Statistics
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    • v.35 no.6
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    • pp.755-764
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    • 2022
  • This paper is concerned with power transformations in estimating GARCH volatility. To handle a semi-parametric case for which the exact likelihood is not known, quasi-likelihood (QL) rather than maximum-likelihood method is investigated to best estimate GARCH via maximizing the information criteria. A power transformation is introduced in the innovation generating QL estimating functions and then optimum power is selected by maximizing the profile information. A combination of two different power transformations is also studied in order to increase the parameter estimation efficiency. Nine domestic stock prices data are analyzed to order to illustrate the main idea of the paper. The data span includes Covid-19 pandemic period in which financial time series are really volatile.

Pre-service Science Teachers' Perceptions of Significance and Usefulness of Evolution and Genetics (예비과학교사들의 진화와 유전에 대한 중요성과 유용성에 대한 인식)

  • Ha, Minsu
    • Journal of Science Education
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    • v.40 no.3
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    • pp.189-202
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    • 2016
  • This study aimed to investigate pre-service science teachers' perceptions of significance and usefulness of evolution and genetics. To this end, 82 pre-service biology teachers and 159 non-biology science teachers answered the items to measure the perceptions of significance and usefulness of evolution and genetics. The validity and reliability were examined using Cronbach alpha, two-dimensional rating scale model Rasch analysis, and factor analysis. The finding illustrated that the test items met the benchmark to be valid and reliable test items. Second, pre-service teachers' perception of significance and usefulness of evolution was independent to that of genetics. The level of pre-service teachers' perception of significance and usefulness of evolution was lower than the level of genetics. Lastly, the levels of pre-service teachers' perceptions of significance and usefulness of evolution and genetics were not significantly different across academic years and majors (biology and non-biology). The findings of this study stressed the importance of teaching significance and usefulness of evolution and genetics in pre-service science teacher education program.

Statistical Analysis of High-Order Power Analysis (고차 전력 분석에 대한 통계적 수식의 일반화)

  • Kim, Min-Su;Kim, Hee-Seok;Hong, Seok-Hie
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.21 no.4
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    • pp.27-37
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    • 2011
  • dth-order power analysis can safely be defended by dth-order masking method. However, as the degree of applied masking method increases, it can significantly decrease effectiveness of cryptosystem. The existing statistical analysis on high-order power analysis contains only analysis on second power analysis. However, this means absent of safety standards when crypto engineers apply 3rd or more order masking. this absent of standards can lead to insignificant usage of masking method which can significantly decrease effectiveness of cryptosystem. In this dissertation, we have generalize statistical values on high-order power analysis to establish these standards. In other words, we have generalized the value of a correlation coefficient when calculation of high-order power analysis methods are performed. That is to say, it can greatly be used to indicate a degrees that can be applied on further usage of masking method.

Diabetes Mellitus prevalence and related factors in Korean Adult over 19 years according to time trend: Data from the Korea National Health and Nutrition Examination Survey (KNHANES) 2011, 2021

  • Ji-Suk Seong
    • Journal of the Korea Society of Computer and Information
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    • v.29 no.8
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    • pp.123-131
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    • 2024
  • The purpose of this study is to identify the prevalence of diabetes and related factors and thereby to provide fundamental data for the prevention and management of diabetes. This study is a secondary analysis based on the raw data from the Korea National Health and Nutrition Examination Survey (KNHANES) for the years 2011 and 2021. Analysis method was frequency analysis, complex samples Chi-square test, complex samples logistic regression analysis. As a result of the study, the factors related to diabetes were sex, age, education level, hypertension, dyslipidemia, and subjective health recognition in 2011(Negelkerke R2=.255), and sex, age, education level, hypertension, dyslipidemia, mother's diabetes, and subjective health recognition in 2021(Negelkerke R2=.327). This study is meaningful in that the factors related to diabetes were identified according to time trend, and the changes in the related factors were confirmed. Development and application of an intervention program to prevent diabetes are necessary.

Probabilities of Pulmonary and Cardiac Complications and Radiographic Parameters in Breast Cancer Radiotherapy (유방암의 방사선치료에서 방사선학적 지표에 따른 폐 및 심장의 부작용 확률)

  • Noh, O-Kyu;Park, Sung-Ho;Ahn, Seung-Do;Choi, Eun-Kyung;Lee, Sang-Wook;Song, Si-Yeol;Yoon, Sang-Min;Kim, Jong-Hoon
    • Radiation Oncology Journal
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    • v.28 no.1
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    • pp.23-31
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    • 2010
  • Purpose: To evaluate the relationship between the normal tissue complication probability (NTCP) of 3-dimensional (3-D) radiotherapy and the radiographic parameters of 2-dimensional (2-D) radiotherapy such as central lung distance (CLD) and maximal heart distance (MHD). Materials and Methods: We analyzed 110 patients who were treated with postoperative radiotherapy for breast cancer. A two-field tangential technique, a three-field technique, and the reverse hockey stick method were used. The radiation dose administered to whole breast or the chest wall was 50.4 Gy, whereas a 45 Gy was administered to the supraclavicular field. The NTCPs of the heart and lung were calculated by the modified Lyman model and the relative seriality model. Results: For all patients, the NTCPs of radiation-induced pneumonitis and cardiac mortality were 0.5% and 0.7%, respectively. The NTCP of radiation-induced pneumonitis was higher in patients treated with the reverse hockey stick method than in those treated by other two techniques (0.0%, 0.0%, 3.1%, p<0.001). The NTCP of radiation-induced pneumonitis increased with CLD. The NTCP of cardiac mortality increased with MHD ($R^2=0.808$). Conclusion: We found a close correlation between the NTCP of 3-D radiotherapy and 2-D radiographic parameters. Our results are useful to reanalyze the previous 2-D based clinical reports about breast radiation therapy complications as a viewpoint of NTCP.

The Length of Postoperative Antituberculous Therapy in Patients with Pulmonary Tuberculosis (폐결핵 환자의 폐절제술 후 항결핵제 투여기간)

  • Kwon, Eun-Su;Song, Jin-Ho;Song, Sun-Dae
    • Tuberculosis and Respiratory Diseases
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    • v.49 no.4
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    • pp.421-431
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    • 2000
  • Background : The length of postoperative drug therapy remains controversial in pulmonary tuberculosis. We analyzed our experiences to determine the postoperative duration of chemotherapy after resection. Method : A retrospective review was performed in 66 of 95 patients that underwent pulmonary resection for pulmonary tuberculosis between January 1993 and December 1998. We compared the relapse rates according to the length of postoperative chemotherapy in each group, classified by the results of sputum AFB culture before the surgery, the number of resistant drugs, the number of prior treatment and the division of anti-TB drugs used postoperatively. Results : Fifty three of 66(80.3%) were men and 13(19.7%) were women with a median age of 33.5 years(range, 16 to 63). The mean lengths of the pre- and post-operative chemotherapies were 4.9 months, and 12.9 months respectively. Five of 66 patients (7.6%) relapsed during the mean period of follow up (39.7 months). In the group less than three times of the prior treatment, there were two relapses (20%) in Ed-the highlight above-rephrase 10 patients that were medicated for 6 months or less, and one relapse in 43 patients (2.3%) that took medicine for more than 6 months (p=0.03). In the group using second-line drugs postoperatively, there was one relapse (25%) in four patients that were medicated for 12 months or less. No patient in a total of 17 that received medicine for more than 12 months relapsed (p=0.03). Conclusion : We recommend that patients with the prior treatment less than three times should be treated for more than 6 months after resection and patients using the second-line drugs postoperatively should be medicated for more than 12 months.

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Properties of Indium Tin Oxide Thin Films According to Oxygen Flow Rates by γ-FIB System (γ-FIB 시스템을 이용한 산소 유량 변화에 따른 산화인듐주석 박막의 특성 연구)

  • Kim, D.H.;Son, C.H.;Yun, M.S.;Lee, K.A.;Jo, T.H.;Seo, I.W.;Uhm, H.S.;Kim, I.T.;Choi, E.H.;Cho, G.S.;Kwon, G.C.
    • Journal of the Korean Vacuum Society
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    • v.21 no.6
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    • pp.333-341
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    • 2012
  • Indium Tin Oxide (ITO) thin films were prepared by RF magnetron sputtering with different flow rates of $O_2$ gas from 0 to 12 sccm. Electrical and optical properties of these films were characterized and analyzed. ITO deposited on soda lime glass and RF power was 2 kW, frequency was 13.56 MHz, and working pressure was $1.0{\times}10^{-3}$ Torr, Ar gas was fixed at 1,000 sccm. The transmittance was measured at 300~1,100 nm ranges by using Photovoltaic analysis system. Electrical properties were measured by Hall measurement system. ITO thin films surface were measured by Scanning electron microscope. Atomic force microscope surface roughness scan for ITO thin films. ITO thin films secondary electron emission coefficient(${\gamma}$) was measured by ${\gamma}$-Focused ion beam. The resistivity is about $2.4{\times}10^{-4}{\Omega}{\cdot}cm$ and the weighted average transmittance is about 84.93% at 3 sccm oxygen flow rate. Also, we investigated Work-function of ITO thin films by using Auger neutralization mechanism according to secondary electron emission coefficient(${\gamma}$) values. We confirmed secondary electron emission peak at 3 sccm oxygen flow rate.

Analysis of Factors for Cartilage Regeneration in Patients Who Underwent High Tibial Osteotomy Combined with Microfracture (근위 경골 절골술과 미세 골절술을 함께 시행 받은 환자 군에서 연골 재생에 영향을 미치는 요인에 대한 분석)

  • Lee, Young Min;Song, Eun-Kyoo;Oh, Ho-Seok;Kim, Yu-Seok;Seon, Jong-Keun
    • Journal of the Korean Orthopaedic Association
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    • v.56 no.5
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    • pp.404-412
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    • 2021
  • Purpose: This study examined the degree of cartilage regeneration by performing second-look arthroscopy in a group of patients who underwent high tibial osteotomy and microfractures for unicompartmental osteoarthritis of the medial knee joint and to determine the factors affecting cartilage regeneration. In addition, this study analyzed whether there is a relationship between the degree of cartilage regeneration and functional results. Materials and Methods: From 2007 to 2015, this study evaluated 81 cases who underwent second-look arthroscopy at the time of plate removal after a microfracture and high tibial osteotomy with a minimum two-year follow-up. The degree of femoral cartilage injury before surgery was classified by ICRS (International Cartilage Research Society), and all were grade III and IV. After second-look arthroscopy, cartilage regeneration was classified into a well-regenerated group (grade I, II) and a poorly regenerated group (grade III, IV). The independent factors influencing cartilage regeneration were identified through multivariate logistic regression analysis. In addition, the functional results were compared before and after surgery between the two groups using the Knee Society score (KSS) and the Western Ontario and McMaster Universities Osteoarthritis Index score (WOMAC). Results: Age, sex, body mass index, postoperative radiologic factors, and preoperative joint condition did not affect the degree of cartilage regeneration significantly. The large cartilage defect (≥2.0 cm2) (p=0.011) and the presence of kissing lesions (p=0.027) were associated with poor cartilage regeneration. No significant difference in the KSS and WOMAC scores was observed between the group with good and poor cartilage regeneration. Conclusion: The presence of a large cartilage defect and kissing lesions is associated with poor cartilage regeneration after high tibial osteotomy and microfracture. On the other hand, the degree of the regenerated cartilage did not show any correlation with the functional outcome.

The Usefulness of Measurement of Whole Body Count in Assessing Bone Marrow Metastasis in Cancer Patients with Increased Periarticular Bone Uptake on Follow-up Bone Scan: A Comparison with Bone Marrow Scan (암환자의 추적 골스캔에서 관절주위 섭취증가시 전신골섭취계수 측정이 골수전이 평가에 도움이 되는가-골수스캔과의 비교)

  • Jin, Seong-Chan;Choi, Yun-Young;Cho, Suk-Shin
    • The Korean Journal of Nuclear Medicine
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    • v.37 no.6
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    • pp.428-436
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    • 2003
  • Purpose: Increased periarticular uptake could be associated with peripheral bone marrow expansion in cancer patients with axial bone marrow metastasis. We compared bone scan and bone marrow scan to investigate whether the increased whole body count in patients with increased periarticular uptake on bone scan is useful in the diagnosis of axial marrow metastasis, and evaluate the role of additional bone marrow scan in these cases. Materials and methods: Twelve patients with malignant diseases who showed increased periarticular uptake on bone scan were included. Whole body count was measured on bone scan and it is considered to be increased when the count is more than twice of other patients. Bone marrow scan was taken within 3-7 days. Results: Five hematologic malignancy, 3 stomach cancer, 2 breast cancer, 1 prostate cancer and 1 lung cacner were included. All three patients with increased whole body count on bone scan showed axial marrow suppression and peripheral marrow expansion. Eight of 9 patients without increased whole body count showed axial marrow suppression and peripheral marrow expansion. One turned out to be blastic crisis of chronic myelogeneous leukemia, and seven showed normal axial marrow with peripheral marrow expansion in chronic anemia of malignancy. The last one without increased whole body count showed normal bone marrow scan finding. Conclusion: Increased whole body count on bone scan could be a clue to axial bone marrow metastasis in cancer patients with increased periarticular uptake, and bone marrow scan is a valuable method for differential diagnosis in these cases.