A SIMPLE VARIANCE ESTIMATOR IN NONPARAMETRIC REGRESSION MODELS WITH MULTIVARIATE PREDICTORS

YOUNG KYUNG LEE,TAE YOON KIM,BYEONG U. PARK 한국통계학회 2006 Journal of the Korean Statistical Society Vol.35 No.1

In this paper we propose a simple and computationally attractive diere-nce-based variance estimator in nonparametric regression models with mul-tivariate predictors. We show that the estimator achievesn1=2 rate ofconvergence for regression functions with only a rst derivative whend, thedimension of the predictor, is less than or equal to 4. Whend > 4, the rateturns out to ben4=(d+4) under the rst derivative condition for the regres-sion functions. A numerical study suggests that the proposed estimator hasa good nite sample performance.AMS 2000 subject classications.Primary 62G08; Secondary 62G20.Keywords.Variance estimation, multivariate regression, rate of convergence.1. IntroductionA homoscedastic regression problem of the formYi = m(Xi) + i (1 i n) (1.1)is considered wherem is an unknown regression function, the errors are indepen-dent and identically distributed random variables with mean zero and variance, and the random design pointsXi are assumed to arise from independent re-alizations of a distribution having a densityf on IRd. Recently, estimation ofReceived January 2006; accepted March 2006.yYoung Kyung Lee was supported by the Brain Korea 21 Project in 2004. Tae Yoon Kimwas supported by KOSEF R01-2003-000-10589-0. Byeong U. Park was supported by KOSEFthrough Statistical Research Center for Complex Systems at Seoul National University.

ACTH 분비 뇌하수체 선암에 의한 쿠싱병

이문호,이정교,이기업,송영기,박중열,김기수,조원경,최기영 대한내분비학회 1994 Endocrinology and metabolism Vol.9 No.2

Primary carcinoma of the pituitary is only rarely reported. About half of the reported cases are nonfunctional. It is generally agreed that the presence of distant metastasis is required to clearly establish the diagnosis of pituitary carcinoma. We have experienced a case of ACTH-producing pituitary carcinoma causing Cushing's syndrome which could be diagnosed by histologic features only without evidence of distant metastasis. A 35-year-old female with Cushingoid appearance was diagnosed as Cushing's disease after biochemical and neuroradiological evaluation. Near total removal of the pituitary tumor was performed. By histopathologic examination, the tumor revealed evidences of histological malignancy such as prominent nuclear pleomorphism, frequent mitoses and extensive tumor necrosis. Pseudosarcomatous components were also noted. By immunohistochemical studies, the tumor cells expressed ACTH. However, there was no evidence of distant metastasis at the initial operation. She was diagnosed as having ACTH producing pituitary carcinoma by histologic feature only. One month later, she complained progressive nausea and vomiting, and follow-up brain MRI revealed regrowing pituitary mass. She was reoperated and near total tumor bulk was removed again followed by radiotherapy with 5580 rads. Four month after the second operation, she developed generalized tonic clonic seizure. Brain CT showed multiple enhancing nodules on left temporal and frontal lobes, and around falx cerebri. She refused further treatment and was managed only with anticonvalsants. About month after discharge she died at home(J Kor Soc Endocrinol 9:136-140, 1994).

한국비서자격시험의 개선점과 비교연구

남자현,이미정,이미영,이아영,정해금,최유정,이미숙,전인선,정혜림 이화여자대학교 법정대학 비서학과 1997 비서학연구 Vol.- No.17

Effective transduction of osteogenic sarcoma cells by a baculovirus vector

Song, Sun U.,Shin, Seok-Hwan,Kim, Soon-Ki,Choi, Gwang-Seong,Kim, Woo-Chul,Lee, Moon-Hee,Kim, Sei-Joong,Kim, In-Ho,Choi, Mi-Sook,Hong, Young-Jin,Lee, Kwan-Hee Microbiology Society 2003 The Journal of general virology Vol.84 No.3

<P>Efficient gene delivery of a baculovirus-derived vector (BV-p53-lacZ) to a human osteogenic sarcoma cell line, Saos-2, was serendipitously found while evaluating the vector for gene delivery to human p53-null tumour cells in a previous study. Therefore, we investigated other human, rat and mouse osteogenic sarcoma and other types of tumour cell lines for transduction efficiency via baculovirus vectors containing a lacZ reporter gene under the control of either a cytomegalovirus or Rous sarcoma virus promoter. The expression of beta-galactosidase protein, assessed by X-Gal staining and beta-galactosidase ELISA, demonstrated an extremely high level of transduction efficiency in some osteogenic sarcoma cell lines, such as U-2OS, Saos-2 and Saos-LM2. These human osteogenic sarcoma cell lines showed levels of beta-galactosidase expression 5-40 times greater than HepG2 cells, which were previously thought to be the mammalian cells most susceptible to baculovirus-mediated gene delivery. The level of acetylated histone proteins in these tumour lines did not correlate well with the high level of reporter gene expression. These results strongly suggest that some osteogenic sarcoma cells are highly susceptible to baculovirus-mediated gene delivery and that a baculovirus-derived vector is an efficient gene delivery vehicle into human osteogenic sarcoma cells.</P>

가평 전주이씨묘 출토복식 고찰

최연우,박윤미,김윤경,김지희,박양희,이선우,차서연,편나영,황혜남,Choi, Yeon Woo,Park, Yoon Mee,Kim, Yoon Gyung,Kim, Ji Hee,Park, Yang Hee,Lee, Seon U,Cha, Seo Yeon,Pyeon, Na Young,Hwang, Hye Nam 한국의류학회 2017 한국의류학회지 Vol.41 No.5

In 1995, the costumes were restored in an unknown woman's tomb at the Jeonju Lee's family cemetery in Gapyeong, Gyeonggi-Do, and there are currently nine items remaining. In this study, we first introduced these 9 relics to academia and analyzed the morphological characteristics of the costumes. We also estimated the time and person of burial compared with costumes unearthed from other burials. Jeogories (short jacket) are all four items. One of these items was unusual in shape, and the upper part of the seop (gusset) was wrinkled and shaped. This type of Jeogori appears only till the 1520s in other tombs. There are also two skirts, one of which is characterized by a superimposed pattern. The top and bottom / middle part of the skirt were rolled up, and the skirt, which was double-rolled up in this way, was first discovered. An analysis of the shape of Jeogori and skirt indicated that the person buried in the Jeonju Lee's family tomb was believed to have survived until the early 16th century. Based on these estimated periods, as a result of looking at the genealogy of Jeonju Lee's family, it was concluded that the tomb was probably a woman named Lee Geum Myeong (李金命) born in the mid-15C and died between the late 15C and the early 16C.

風船心房中隔切開術로 好轉된 大血管轉位 1例 報告 : A Case Report

李夏聖,白泰宇,鄭眞榮,金昶洙,車濬甲 대한소아과학회 1971 小兒科 Vol.14 No.2

현행 중학교 과학 실험·실습교육에 대한 교사들의 견해와 개선방안

이윤종,기우항,김영호,정원우,양승영,강용희,안병호,임성규,윤일희,김중욱,강동진 경북대학교 과학교육연구소 1996 科學敎育硏究誌 Vol.20 No.-

The status of facilities, management of the experiment, practices, and Science education teaching method in middle school have been investigated. The present status and reasonable management of middle school science education have been grasped from the questionaires. The results are as follows : The reasonable management for expeiments and practices of science education were scanty in the middle school around the urban and rural schools owing to the shortage of facilities and equipments, crowded class, excessive classes, work for teachers, excessive contents of present textbook and insufficience of administrative support etc. The current teaching method of middle school science has emphasized knowledge. This fact does not satisfy the objective of learning due to lack of teaching method. Desirable directions for the improvement of present status of middle school science education were proposed in this paper.

하시모토갑상선염에 동반된 골수를 침범한 ( 병기 4E 기 ) 원발성 갑상선 림프종 1 예

이기업,송영기,박중열,김기수,김상희,공경엽,조재근,추윤호,엄완식,지현숙 대한내분비학회 1994 Endocrinology and metabolism Vol.9 No.4

Primary lymphoma of the thyroid is a relatively rare malignant tumor of the thyroid. It is known to be frequently associated with Hashimoto's thyroiditis. In Korea, a few cases of primary lymphoma of the thyroid have been reported and most of these cases were in the stage I E or II E. Recently, we experienced a case of the primary thyroid lymphoma, stage IV E associated with Hashimoto's thyroiditis in a 70-year-old woman who presented with dysphagia and dyspnea due to rapidly enlarging neck mass. She was treated with combination chemotherapy(cyclophosphamide, adriamycin, vincristine and methylprednisolone) and local radiotherapy and achieved partial response with resolution of dysphagia and dyspnea(J Kor Soc Endocrinol 9: 390-394, 1994).

블록들의 유사성을 고려한 Adaptive Block-Wise RPLS

윤경우,이영학,한종훈 한국화학공학회 2003 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.41 No.5

부분 최소 자승법 (partial least squares, PLS)은 복잡한 공분산 구조를 가진 상관성이 큰 변수들이 포함된 공정을 모델링 하는데 효과적으로 사용되어 왔다. 하지만 공정 변화에 적응하는 온라인 모델을 만들기 위해 부분 최소 자승법을 이용하는 것은 많은 제약이 따른다. 그래서 많이 이용되고 있는 방법이 recursive PLS(RPLS)이다. RPLS는 새로운 데이터 샘플이 들어오면 모델을 갱신 한다. 하지만 데이터의 상당한 양이 모이거나 공정의 큰 변화가 있을 때까지 모델을 갱신하지 않을 수도 있다. 따라서 이 논문에서는 공정 변화에 잘 적응하고 모델 갱신을 블록 단위로 하는 block-wise RPLS의 온라인 적응 방법인 moving window 방법을 이용하였다. Block-wise RPLS는 희귀 모델을 만들고 검증하는데 필요한 계산 부하를 감소시키는 효과가 있다 본 연구에서는 모델을 구성하는 윈도우내에 있는 블록들 사이의 상관관계를 나타내는 지표를 정의한 다음, 그 지표를 통해 forgetting factor를 정하는 방법을 제시하였다. 이 방법은 공정에 대한 일반적인 지식이 필요하지 않고 단지 데이터 블록의 상관관계만으로 적응 모델의 예측력을 높일 수 있는 방법이다. 따라서 다른 방법들이 나타내지 못한 상관성 정보를 포함시켰다. 이 방법을 기반으로 정유 공장의 가열로의 NO_(x)(nitrogen oxides) 배출 농도를 예측하는 모델을 forgetting factor를 이용해 구성했고, 이 forgetting factor에 의해 예측력이 최소 에러 값의 95%이상 근접함을 확인하였다. Partial least squares (PLS) regression has been effectively used as one of the data-driven empirical modeling to deal with a large number of variables in the complicated covariance structure. But Partial least squarer (PLS) regression has limitations in the online model update. Therefore, recursive PLS has ken used for the online adaptation of the model. The RPLS algorithm is implemented as soon as some new samples are available. It may be desirable not to update the model until significant amount of data are collected and the process has gone through significant changes. In this paper. we used the block-wise recursive partial least squares (RPLS) algorithms with a moving window for the adaptation of the model according to the process shins. The block-wise RPLS algorithm has been used to reduce computational load in PLS regression and its cross-validation. In this work we defined the index to represent correlation between blocks and proposed how to determine the forgetting factors through it. This proposed method is to improve the prediction power of the adaptive modeling considering correlation between blocks without general process knowledge. Therefore, this proposed method included correlation information that different methods did not express. The method was tested to process heaters in the oil refining wmpany. We costructed the prediction model of the effluent NO, composition with forgetting factors and showed that the prediction power approximated more than 95% of the minimum error.

현행 중학 수학 교과서의 비교 분석

기우항,김영호,이윤종,정원우,김민숙 경북대학교 과학교육연구소 1997 科學敎育硏究誌 Vol.21 No.-

The purpose of this study is to compare and analyze the eight current mathematics textbooks in order to them effectively in the course of instruction according to the result. Basically the study has been carried out to compare and analyze what is the difference between the current curriculum and the last one, and the development of the teaching procedure, the difference of the quality and contents in the eight kind of text books.