변환-역변환을 통한 자기회귀이동평균모형에서의 예측값 추정

여인권,조혜민,Yeo, In-Kwon,Cho, Hye-Min 한국통계학회 2008 응용통계연구 Vol.21 No.3

시계열자료 분석에 있어 주요 목적 중에 하나는 미래에 대한 예측 값을 추정하는 것이다. 이 논문에서는 정상자기회귀이동평균 모형에서 변환-역변환 방법을 이용하여 예측값을 구하는 과정에서 발생하는 문제에 대해 알아보고 회귀분석에서 제안되었던 smearing 추정방법을 시계열분석에서 사용할 수 있도록 붓스트랩을 이용하여 수정한 추정법을 소개한다. Yeo-Johnson 변환 (2000)을 이용한 KOSDAQ지수의 수익률 실증분석을 통해 기존에 사용되고 있는 방법의 문제점과 제안된 방법의 적절성에 대해 고찰해 보았다. One of main goals of time series analysis is to estimate prediction of future values. In this paper, we investigate the bias problem when the transformation and back- transformation approach is applied in ARMA models and introduce a modified smearing estimation to reduce the bias. An empirical study on the returns of KOSDAQ index via Yeo-Johnson transformation was executed to compare the performance of existing methods and proposed methods and showed that proposed approaches provide a bias-reduced estimation of the prediction value.

변환된 자기회귀이동평균 모형에서의 예측구간추정

조혜민,오승언,여인권,Cho, Hye-Min,Oh, Sung-Un,Yeo, In-Kwon 한국통계학회 2007 응용통계연구 Vol.20 No.3

시계열자료를 분석하는데 있어 중요한 목적 중에 하나가 미래값에 대한 예측이다. 일반적으로 자기회귀이동평균모형에서는 백색잡음이 정규분포를 따른다는 가정 하에서 모수의 추론과 예측 및 예측구간의 추정이 이루어지고 있다. 그러나 자료가 이러한 가정을 만족하지 않는 경우, 자료를 가정에 맞게 변환시킨 후 분석하는 방법을 생각해 볼 수 있다. 이 논문에서는 변환된 자료를 분석하여 얻은 결과를 이용하여 본래의 척도에서의 미래값에 대한 예측구간을 추정하는 문제에 대해 알아본다. 제안하는 방법에서는 먼저 적절한 변환을 이용하여 자료를 정규가정을 만족하도록 변환시키고 변환된 자료를 이용하여 미래값에 대한 예측구간을 추정한 후, 역변환을 이용하여 예측구간을 추정한다. 이 논문에서는 시계열분석에서 모델링이 상대적으로 어려운 왜도의 문제를 해결하기 위해 Yeo-Johnson 변환을 중심으로 한 방법론을 소개한다. 모의실험 결과 제안된 방법에 의한 단측예측구간의 포함확률이 변환을 사용하지 않은 구간보다 명목수준에 가까운 것을 확인하였다. One of main aspects of time series analysis is to forecast future values of series based on values up to a given time. The prediction interval for future values is usually obtained under the normality assumption. When the assumption is seriously violated, a transformation of data may permit the valid use of the normal theory. We investigate the prediction problem for future values in the original scale when transformations are applied in ARMA models. In this paper, we introduce the methodology based on Yeo-Johnson transformation to solve the problem of skewed data whose modelling is relatively difficult in the analysis of time series. Simulation studies show that the coverage probabilities of proposed intervals are closer to the nominal level than those of usual intervals.

Helicobacter pylori와 대장균의 Shuttle Vector 개발

조명제,이우곤,이상룡,김경희,안영숙,김성희,김현주,류복덕,최여정,윤영혜,백승철,전영석,이광호 경상대학교 유전공학연구소 1997 遺傳工學硏究所報 Vol.16 No.-

In this study, a vehicle vector using cryptic plasmids was constructed for gene transfer in Helicobacter pylori. pHP51(3.9 kb) and pHP489(1.2 kb) were selected for constructing vectors from cryptic plasmid of H. pylori isolates in Korea. The HindⅢ-digestedDNA fragment(1.2kb) of pHP489 and 1.6kb DNA fragment of pHP51 were ligated with a kanamycin resistance gene(aph3'-Ⅲ) from C. jejuni to produce the recombinant plasmids pHP489K and pHP51K, respectively. Transformation frequency of pHP51K by electroporation was low. But pHP489K could be effectively transformed into various H. pylori strains. In order to design an intermdiate vehicle vector for gene transfer into H. pylori, pBlueHP489K was prepared by recloning pHP489K DNA into pBluescript and pTZ19R vector. This vector permitted the DNA fragment containing pHP489 sequence, aph3'-Ⅲ, and cloned DNA to be cut and self-ligated in the SacⅠ site after cloning. ureA and ureB gene were inserted into pBlueHP489K, resulting in pBlueHP489K/AB. The DNA fragment containing pHP489, kanamycin resistance gene(aph3'-Ⅲ), and urease structural gene was cut away from pBlueHP489K/AB and self-ligated to generate pBlueHP489K/AB. pBlueHP489K/AB made urease-negative H. pylori strains restore their urease activity. By this experiment, pBlueHP489K was confirmed to be the vehicle system for transferring H. pylori genes.

Serum TSH Level in Healthy Koreans and the Association of TSH with Serum Lipid Concentration and Metabolic Syndrome

( Yeo Kyung Lee ),( Jo Eun Kim ),( Hyun Ju Oh ),( Kyung Sun Park ),( Soo Kyung Kim ),( Seok Won Park ),( Moon Jong Kim ),( Yong Wook Cho1 ) 대한내과학회 2011 The Korean Journal of Internal Medicine Vol.26 No.4

Background/Aims: The proper treatment of subclinical hypothyroidism and the normal range of serum thyroid stimulating hormone (TSH) concentration are intensely debated. However, few reports have investigated TSH concentrations in Asian ethnic groups. Therefore, the present study was designed to define the TSH reference range in a Korean population and to investigate the metabolic significance of TSH concentration. Methods: We enrolled patients who underwent medical examination at the CHA Bundang Medical Center. Anthropometric data were evaluated, and serum TSH, free T4, and lipid profiles were assayed. Results: A total of 7,270 subjects were included. Mean TSH concentration of the study population was 1.82 ± 0.95 mU/L, and we observed a sex-related difference in TSH concentration (male, 1.67 ± 0.87 mU/L; female, 2.02 ± 1.01 mU/L; p < 0.01). When the 2.5 and 97.5 percentiles were calculated, 95% TSH reference limits were 0.52-4.29 mU/L. TSH concentration was higher in elderly subjects, during winter, in postmenopausal women, and in obese males. Moreover, TSH showed significantly positive correlations with serum total cholesterol, triglyceride, and low density lipoprotein cholesterol regardless of sex, age, season, obesity, or menopausal status (all p < 0.01). Finally, TSH concentration was positively related to the prevalence of metabolic syndrome. Conclusions: We demonstrated the association between TSH concentration within the normal reference range and serum lipid levels. TSH concentration varies according to sex, age, season, and body mass index (only in males). Moreover, high normal TSH levels were significantly associated with an increased prevalence of metabolic syndrome, which may be of importance when evaluating subjects with high normal TSH concentration.

암환자가 지각한 좋은 간호사의 특성

조남옥,홍여신,한성숙,엄영란 병원간호사회 2006 임상간호연구 Vol.11 No.2

This study was based on a phenomenological approach. All patients were hospitalized cancer patient who had insight about cancer. Data were collected through in-depth interviews during the months of July and August, 2004. Interviews lasted one and half hours on an average and data were analyzed by Van Kaam method. Result: Four essential attributes of good nurse were identified: compassion, need fullfillment, virtuous and professional expertism. And four essential attributes of bad nurse were identified: insincere, neglect, disregard and lack of expertism. Conclusion: The results of this study showsd that cancer patients perceived the good nurse as possessing the qualities of compassion for patients, having virtuous attitude and professional expertism and fullfilling patient's need. And cancer patients perceived the nuse showing familial intimacy as a good nurse. This perception of cancer patients was influenced by tradition and cultural background. So there is a need for further research about our own culture and its influences on nursing practice.

턱관절을 포함한 하악골의 충격시 골절 발생기전에 대한 연구

조세종,김여갑 大韓顎顔面成形再建外科學會 2002 Maxillofacial Plastic Reconstructive Surgery Vol.24 No.6

The purpose of this study is to investigate fracture mechanism of mandible including TMJ using dynamic finite analysis. We made mandibular finite element model with 3-D doctor(Able Soft Co. USA) based on CT scan film and performed mechanical experiments as to impulsive force direction, impulsive time, impulsive loading to it. At first, the load was applied on the mandibular symphysis, body, angle, subcondyle, and then impulsive stress ditribution was measured on 14 points of finite model. Second, various magnitude of load were applied on madibular symphsis under constant impulsive time, and various impulsive time were done on it under costant loading. The conclusions of this study were as follows: 1. The possibility of fracture is the most high in mandibular angle and subcondylar area. 2. The impulsive stress and deformation were larger in labial surface in symphysis and buccal one in subcondylar area 3. The subcondyle had the most possibility of fracture regadless of impacted area, it might result in multiple fracture in this case. 4. The disc had the tendency to reduce impulsive stress on entire mandible as buffer. 5. Under constant impulsive time, as impulsive loading increased, as the possibility of fracture increased. 6. Under constant impulsive energy, as impulsive time shortened, as the possibility of fracture increased

골격성 3급 부정교합자시 악교정 수술후 골격이동량에 따른 설골의 위치와 상기도 변화에 관한 연구

조세종,김여갑 대한악안면성형재건외과학회 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.3

The goal of this study is the comparison of upper airway size and change of skeletal Class I group and skeletal Class III group (before operation, within 2 weeks after operation, 6 months after operation) respectively. At first, we measured the lines between selected upper air way landmarks on lateral cephalometric x-ray film of skeletal Class I 40 persons whoes age were 23-26 years old, ,and did the same lines of landmarks of skeletal Class III 44 persons who had not been operated yet, were within 2 weeks after operation, were 6 months after operation. And we compared it respectively and analyzed it with paired t-test. We studied the relationship of those on produced data. 1.Skeletal Class III group was narrower in nasopharyngeal air way space than that of skeletal Class I group, and increased in thickness of oropharyngeal, hypopharyngeal wall within 2 weeks after operation, and reduced in nasopharyngeal, oropharyngeal air way space, and did in thickness of nasopharngeal, hypopharyngeal wall 6 months after operation. 2.Skeletal Class III group reduced in nasopharyngeal, oropharyngeal air way space, and increased in thickness of nasopharyngeal, oropharyngeal, hypopharyngeal wall within 2 weeks after operation, restored the thickness of nasopharyngeal, oropharyngeal wall, but did not restored nasopharyngeal, oropharyngeal, hypopharyngeal air way space. 3.Vertical length from hyoid bone to mandibular plane did not have signifacant difference from Class I group but after operation, it increased more than Class I group significantly. 4.The size of airway reduced after operation. Among this, oropharyngeal airway most reduced.

필라델피아 염색체 양성 급성골수성백혈병에서 Imatinib Mesylate로 분자학적 관해를 유도한 후 성공적인 자가 말초혈액 조혈모세포이식이 시행되었던 1예

김여경,이제중,이병환,변정래,조덕,이일권,정익주,양동욱,김형준 대한조혈모세포이식학회 2003 대한조혈모세포이식학회지 Vol.8 No.1

저자들은 필라델피아 염색체 양성 급성골수성백혈병 환자에서 복합항암화학요법으로 혈액학적 완전관해를 유도하고, imatinib mesylate를 이용하여 분자학적 관해를 유도한 후, 성공적으로 자가 말초혈액조혈모세포이식을 시행하였던 1예를 경험하였기에 이를 보고하는 바이다. Philadelphia chromosome (Ph¹)-positive acute myeloid leukemia (AML) is very rare disease, comprising 3~4% of the AML, and is a clinically distinct entity with poor clinical outcome with conventional chemotherapy. We report a case of Ph¹-positive AML who underwent successful autologous peripheral blood stem cell transplantation after achieving a molecular remission with imatinib mesylate.

IMT-2000 환경에서 Block Design을 응용한 회의용 인증메카니즘의 설계

이여진,김중태,조영주,유성진,배용근 조선대학교 전자정보통신연구소 2003 電子情報通信硏究所論文誌 Vol.6 No.1

In this paper, we present conference key authentication mechanism by employing an algebraic method on IMT-2000 environment To accomplish this, Symmetric Balanced Incomplete block design is applied for generating the communication key and then this key is distributed to participants Through this technique for creating a conference key and mutual authentications performed based on identification information, the communication protocol is designed The protocol presented minimizes the transmission complexity for generating a conference key On a special case the time complexity is O(v√v), where v is the number of participant. The security of the mechanism, which is a significant problem in the construction of Secure system, can be, proved as computationally difficult to calculate as factoring and discrete logarithms.

밤나무 耐寒性品種 選拔에 관한 연구

李麗夏,趙台煥,洪性珏 건국대학교 1976 學術誌 Vol.20 No.2

32 cultivars of chestnut were collected at the Kyunggido Forest Experimental Station, Oh-San, Kyunggido, Korea on November and December, 1976. The freezing resistance of winter bud, cambium and xylem parenchyma of the cultivars was measured to select out freezing resistant cultivars under the condition of early winter in Korea. The winter bud showed lowest freezing resistance among tissue parts. The xylen parenchyma attained relatively higher freezing resistance than the cambium did. On the basis of the freezing resistance of winter bud eleven cultivars which showed relatively high freezing resistance were selected among 32 cultivars of chestnuts. Again on the basis of the freezing resistance of cambium which is often one of the critical factors in winter damage, another eleven freezing resistant cultivars were selected. The eight cultivars which showed both freezing resistance of winter bud and cambium were chosen. These were in order from highest to lowest selected freezing resistant cultivars, wild chinese chest nut, Dan-Taeck, OK-Kwang, Bong-Eeh, Chuk-Pa, Da-Ap, Mahn-Juk, Ahn-Goon.