공간-시계열 모형을 이용한 결측대체 방법에 대한 연구

이진희,신기일,Lee, Jin-Hee,Shin, Key-Il 한국통계학회 2007 응용통계연구 Vol.20 No.3

표본조사에서 항목무응답 발생 시 결측대체에 사용되는 일반적인 방법은 결측변수와 관계 있는 보조변수를 이용하는 것이다. 최근 이진희 등 (2006)은 2002년 강원지역의 농가경제 자료를 이용하여 표본조사에서 공간통계를 이용한 결측대체 (missing imputation) 방법을 비교하였으며, 자료들 사이에 지역적 상관이 존재할 때 이를 이용한 결측대체가 효율적임을 보였다. 본 논문에서는 이를 확장한 개념으로, 강원지역의 2000-2002까지의 월별 자료가 공간상관과 시계열상관이 존재함을 확인하고 이 관계를 결측대체에 이용하였다. 또한 공간상관과 시계열상관이 모두 존재할 경우 공간시계열 모형을 이용한 결측 대체 방법이 공간모형을 이용하였을 때에 비해 더 효율적임을 모의실험을 통해 확인하였다. It is a common practice to use the auxiliary variables to impute missing values from item nonresponse in surveys. Sometimes there are few auxiliary variables for missing value imputation, but if spatial and time autocorrelations exist, we should use these correlations for better results. Recently, Lee et al. (2006) showed that spatial autocorrelation could be efficiently used for missing value imputation when spatial autocorrelation existed, using the data from the farm household economy data in Gangwon-do, 2002. In this paper, we present au evaluation of spatial and space-time nonresponse imputation methods when there exist spatial and time autocorrelations using the monthly data during 2000-2002 from the same data previously used by Lee et al. (2006). We show that space-time imputation method is more efficient than the other through the numerical simulations.

혈뇨 환아에서 고칼슘뇨군과 비고칼슘뇨군의 혈액 및 소변화학검사와 신기능 지표들의 비교

이진희,이현승,이근영,장필상,이경일,김동언,Lee, Jin-Hee,Lee, Hyun-Seung,Lee, Keun-Young,Jang, Pil-Sang,Lee, Kyung-Yil,Kim, Dong-Un 대한소아신장학회 2007 Childhood kidney diseases Vol.11 No.2

목 적 : 육안적 또는 현미경적 혈뇨를 주소로 24시간 소변화학검사를 시행한 환아들의 의무 기록을 후향적으로 조사하여 고칼슘뇨군과 비고칼슘뇨군으로 나누어 두 군의 혈액 및 소변화학검사와 그로부터 계산된 각 용질의 배설량, 청소율, 분획배설 등에 있어서 두 군간에 차이점이 있는지 비교하였다. 방 법 : 1997년 2월부터 2007년 2월까지 10년간 가톨릭의대 의정부성모병원 소아과에서 육안 또는 현미경적 혈뇨를 주소로 24시간 소변검사를 시행한 환아 중, 단백질 배설량이 4 mg/$m^2$/시간 이상으로 단백뇨가 동반된 경우는 제외하고, 소변 칼슘 배설량이 4 mg/kg/일 이상으로 특발성 고칼슘뇨증으로 진단 받은 30명과 소변 칼슘배설량이 3mg/kg/일 미만인 비고칼슘뇨군 환아 41명을 대상으로 하여 혈액화학검사, 기본 소변검사, 24시간 소변화학검사로부터 각종 소변 용질의 배설량, 청소율, 분획배설 등을 구하여 두 군간에 차이점이 있는지를 비교 분석하였다. 결 과 : 고칼슘뇨군(30명)과 비고칼슘뇨군(41명)에서 육안적 혈뇨는 각각 24명(80%), 17명(42%)으로 고칼슘뇨군에서 육안적 혈뇨의 비가 높았다. 임의채취뇨의 Ca/Cr 비는 각각 $0.34{\pm}0.15,\;0.15{\pm}0.13$이었으며 고칼슘뇨군 30명 중 28명의 임의채취뇨 Ca/Cr 비는 0.2 이상이었고, 비고칼슘뇨군 41명 중 36명의 임의채취뇨 Ca/Cr 비가 0.2 미만이었다. 혈액화학검사에서 고칼슘뇨군과 비고칼슘뇨군의 혈청 칼슘은 각각 $9.8{\pm}0.5 mg/dL,\;9.5{\pm}0.5 mg/dL$로 고칼슘뇨군이 통계학적으로 유의하게 높았다(P=0.033). 24시간 소변의 칼슘농도는 각각 $14.7{\pm}7.7 mg/dL,\;3.3{\pm}2.2 mg/dL$로 고칼슘뇨군이 유의하게 높았고(P<0.001), 칼슘배설량도 각각 $6.1{\pm}2.9 mg/kg/$일, $1.5{\pm}0.9 mg/kg/$일로 고 칼슘뇨군에서 유의하게 높았다(P<0.001). 크레아티닌 청소율로 구한 사구체여과율은 각각 $93.7{\pm}31 mL/min,\;79.5{\pm}32.0 mL/min$로 고칼슘뇨군이 유의하게 높았다(P=0.048). 24시간 소변의 요소농도는 각각 $797{\pm}316 mg/dL,\;569{\pm}329 mg/dL$로 고칼슘뇨군에서 유의하게 높았고(P=0.015), 요소배설 량도 각각 $341 {\pm}102 mg/kg/$일, $233{\pm}123 mg/kg/$일로 고칼슘뇨군에서 유의하게 높았다(P=0.002). 나트륨 배설량은 두 군간에 차이가 없었으나 나트륨 분획배설(FENa)은 각각 $1.0{\pm}0.4%,\;1.3{\pm}0.6%$로 고칼슘뇨군에서 유의하게 낮았다(P=0.029). 소변배설량은 두 군간에 차이가 없었으나 소변의 삼투질농도는 각각 $393{\pm}103 mOsm/kg\;H_2O,\;304{\pm}96 mOsm/kgH_2O$로 고칼슘뇨군에서 더 농축된 소변을 보았다(P=0.003). 결론 :고칼슘뇨군의 소변화학검사의 가장 특징적인 소견은 요소 배설과 사구체여과율의 증가로서 이는 고칼슘뇨군이 비고칼슘뇨군에 비하여 고단백식이를 하고 있을 가능성을 시사한다. 나트륨과 칼슘은 사구체 여과가 증가함에 따라 원위세뇨관 및 집합관에 도달하는 양도 증가하고 그 곳에서 나트륨의 재흡수 기전이 매우 정교하게 이루어지는데 비하여 칼슘의 그 것은 그렇지 못하여 고칼슘뇨증을 일으켰을 가능성이 있다. 향후 고칼슘뇨 환아를 진료함에 있어서 단백질 섭취 등식이 습관의 문진과 함께 식이요법도 고려해 보아야 할 것으로 생각된다. Purpose : The purpose of this study was to investigate whether hypercalciuria patients with hematuria show different renal indices compared to non-hypercalciuria patients with hematuria. Methods : We retrospectively reviewed the medical records of patients with gross or microscopic hematuria whose blood chemistry and 24 hour urine chemistry were examined. After excluding the patients with more than $4 mg/m^2/day$ proteinuria or the patients with urinary calcium excretion between 3 and 4 mg/kg/day, we divided the patients into two groups: a hypercalciuria group whose calcium excretion was more than 4 mg/kg/day(n=30) and a non hypercalciuria group whose calcium excretion was less than 3 mg/kg/day(n=41). The urinary excretion, clearance, and fractional excretion(FE) of Na, K, Cl, Ca, P, urea, and creatinine were calculated and compared between the two groups. Results : The hypercalciuria group had more calcium excretion($6.1{\pm}2.9$ vs $1.5{\pm}0.9 mg/kg/day$), more urea excretion($341{\pm}102$ vs $233{\pm}123 mg/kg/day$), greater glomerular filtration rate(GFR) ($93.7{\pm}31.1$ vs $79.5{\pm}32.0 mL/min$) but lower FENa($1.0{\pm}0.4%$ vs $1.3{\pm}0.6%$) than the nonhyper-calciuria group, although the urinary sodium excretion was similar between the two groups. Conclusion : The greater urea excretion and GFR in hypercalciuric patients suggest that they might be on a higher protein diet than the non-hypercalciuria group. The increased glomerular filtration of sodium and calcium induced by the higher GFR in hypercalciuria would have increased their delivery to the distal tubule, where sodium is effectively reabsorbed but calcium is not, which is suggested by the lower FENa but higher FECa in hyercalciuria. It is recommended that the diet of hematuria patients be reviewed in detail at initial presentation and during treatment.

하천에 있어서 자연성의 보전, 정비, 창출에 관한 연구(I) - 농촌지역에서의 토지이용과 하천수질과의 상관성 -

이진희,이행렬,이재근,이동근,김훈희,Lee, Jin-Hee,Lee, Haeng-Youl,Lee, Jae-Kun,Lee, Dong-Kun,Kim, Hoon-Hee 한국환경복원기술학회 1998 한국환경복원기술학회지 Vol.1 No.1

The sources of the pollution on a river are divided into two classes, one the point source and the other non-point source. In raining, especially, the non-point source discharged from paddy, residential area, road ${\cdots}$ etc have correlations with the land use. This study was carried out to find out the model to estimate the quality of water in a river according to the land use. Land use data (Pungse-Myeoun and Kwangduk-Myeoun in Chonan) were produced from Landsat TM (Thematic Mapper) and topographic map. Total nitrogen(TN) and total phosphorus(TP) general indices for the degree of pollution in river were measured during 11 months. Correlations between two variables(Land use and Pollutants(TN, TP)) were explained by the regression coefficient. As a result of this study, we found that among the five types of land use, the residential area, store area and paddy have significant effects upon the quality of water in a river. The results of this study will be applied to pre-estimate the degree of pollution in river broadly and to offer basic data in establishing the land use plan and the concept on the conservation of the river in rural area.

전기시설에 따른 문제

이진희,Lee, Jin-Hui 한국화재보험협회 1976 防災와 保險 Vol.6 No.-

셀간 협력 통신 기반의 적응적 다중 사용자 다중 안테나 전송 기법

이진희,고영채,Lee, Jin-Hee,Ko, Young-Chai 한국전기전자재료학회 2011 전기전자재료학회논문지 Vol.24 No.2

In multicell wireless systems with insufficient frequency reuse, user transmission will suffer other-cell interference (OCI). Cell cooperation is an effective way to mitigate OCI and increase the system sum rate. An adaptive scheme for serving one user in each cell was proposed in [1]. In this paper, we generalize that scheme by serving two users in each cell with adaptive zeroforcing beamforming (ZF) strategies. Based on our derived statistics of the signal-to-noise plus interference ratios, we choose the scheme to maximize the total ergodic sum-rate based on user locations. Through the numerical examples, we show that the total system sum rate can be improved by selecting appropriate transmitting strategy adaptively. As a result, our proposed system can explore spatial multiplexing gain without additional power and thus improves total system sum rate significantly.

생약 복용에 따른 아플라톡신 B₁의 인체모니터링 연구

이진희,류희영,김현경,김도정,이영주,정수희,장동덕,김형수,홍연표,윤혜성,Lee, Jin-Hee,Ryu, Heui-Young,Kim, Hyun-Kyung,Kim, Do-Jung,Lee, Young-Joo,Jung, Su-Hee,Jang, Dong-Deuk,Kim, Hyung-Su,Hong, Yeon-Pyo,Yoon, Hae-Seong 한국환경보건학회 2010 한국환경보건학회지 Vol.36 No.2

Aflatoxin $B_1$, a known human carcinogen, is the member of aflatoxin subfamily that is most frequently found in contaminated foods. Epidemiological studies have suggested that aflatoxins may be associated with human liver cancer and acute hepatitis. Recently it was reported that the traditional medical herbs sold in domestic markets are contaminated with aflatoxins. Long-term administration of these contaminated medicines could result in adverse health effects. Therefore, it is important to evaluate the levels of exposure to aflatoxin in people who ingest traditional herbal medicines. Blood samples were collected, before and after the herbal medicine intake, from 151 subjects who visited the hospital. The metabolite of aflatoxin $B_1$ in blood, aflatoxin $B_1$-albumin (aflatoxin $B_1$-lysine), is reportedly an appropriate internal exposure indicator, and its levels in the collected bloods were therefore analyzed using a liquid chromatography-mass spectrometry. The analytical method of aflatoxin $B_1$-lysine in blood was firstly optimized in Korea and the levels were detected below quantification limits (2 pg/mg albumin) in this study population. Consequently, the exposure levels of aflatoxin $B_1$ by ingestion of herbal medicines were low but it is important to monitor routinely due to the possibility of risk on the aflatoxin exposure.

국내 도로 환경에 특화된 자율주행을 위한 멀티카메라 데이터 셋 구축 및 유효성 검증

이진희,이재근,박재형,김제석,권순,Lee, Jin-Hee,Lee, Jae-Keun,Park, Jaehyeong,Kim, Je-Seok,Kwon, Soon 대한임베디드공학회 2022 대한임베디드공학회논문지 Vol.17 No.5

Along with the advancement of deep learning technology, securing high-quality dataset for verification of developed technology is emerging as an important issue, and developing robust deep learning models to the domestic road environment is focused by many research groups. Especially, unlike expressways and automobile-only roads, in the complex city driving environment, various dynamic objects such as motorbikes, electric kickboards, large buses/truck, freight cars, pedestrians, and traffic lights are mixed in city road. In this paper, we built our dataset through multi camera-based processing (collection, refinement, and annotation) including the various objects in the city road and estimated quality and validity of our dataset by using YOLO-based model in object detection. Then, quantitative evaluation of our dataset is performed by comparing with the public dataset and qualitative evaluation of it is performed by comparing with experiment results using open platform. We generated our 2D dataset based on annotation rules of KITTI/COCO dataset, and compared the performance with the public dataset using the evaluation rules of KITTI/COCO dataset. As a result of comparison with public dataset, our dataset shows about 3 to 53% higher performance and thus the effectiveness of our dataset was validated.

Fibrin Polymer 의 생성 메카니즘에 관한 연구

이진희,김두식 ( Jin Hee Lee,Doo Sik Kim ) 생화학분자생물학회 1988 BMB Reports Vol.21 No.4

Conversion of fibrinogen to fibrin polymer has been investigated. It is noteworthy to find that excess basic amino acids, either L-arginine or L lysine, are capable of polymerizing fibrinogen at neutral pH simply by charge-neutralization process without removing fibrinopeptides. This observation strengthens the notion that both specific orientation and balance of electric charge of the protein molecule are essential factors for the fibrin polymerization. Chemical modification of arginine residue(s) of fibrinogen completely inhibits thrombin-catalyzed conversion to fibrin polymer, which confirms that the specific arginine is recognized as a cleavage site by thrombin to yield fibrinopeptides and fibrin. The molecular weights of three different polypeptide chains of fibrinogen are reduced to lower than 47,000 upon proteolytic digestion with chymotrypsin. Surprisingly, however, these lower molecular species of fibrinogen are found to be polymerized in the presence of thrombin. Therefore, extensive structural analyses of the chymotrypsin-treated fibrinogen will contribute to define the essential interaction domains of fibrin units required for polymerization.

연구논문 - 에너지 , 환경분과 : 최대 잉크 전이율을 이용한 비도공지의 인쇄적성에 관한 연구

이진희,박종훈,전성재,이재수 ( Jin Hee Lee,Jong Hun Park,Sung Jai Jeon,Jan Soo Lee ) 한국공업화학회 1997 한국공업화학회 연구논문 초록집 Vol.1990 No.3

유시티 도래에 따른 도시민 생활양식 변화가 도시공간에 미치는 영향

이진희,신동빈,Lee, Jin Hui,Shin, Dong Bin 한국공간정보학회 2012 한국공간정보학회지 Vol.20 No.5

이 연구의 목적은 유시티에 따른 생활양식 및 도시공간의 변화를 분석하여 이를 반영한 도시 정책 방향을 제안하는 것이다. 유시티에서의 도시공간 변화 분석에 있어서는 도시민 설문조사를 통한 생활양식 변화를 예측하여 추론하는 행태적 접근 방법을 사용하였다. 분석 결과 도심을 주요 활동공간으로 하는 도시기능에 있어 통행량 및 이용의 감소와 입지 선호도의 변화로 도심 집중화 약화와 도시의 외연적 확산이 예상되었다. 개별 용도에 있어서는 통행량과 이용의 감소에 따라 규모나 개수가 축소될 것으로 예상되었으며, 기존 공간의 재편에 있어서는 특히 공공공간에 있어 유비쿼터스 기술을 활용하여 다양한 도시활동을 수행할 수 있는 다목적 공간으로의 변화가 전망되었다. 앞으로 유시티가 정착하면 도시의 공간구조와 시설별 수요가 도심과 비도심에 따라 변화가 예상되므로 이를 반영한 도시계획이 필요하다. 동시에 효율적이고 유연한 도시공간이 조성될 수 있는 발판이 마련되어야 한다. This study analyzes the changes of lifestyle and urban spaces with the advent of U-City and tries to propose a direction of urban policies reflecting them. For this, it investigates lifestyle changes to predict the phase of urban spaces in the future. In a survey on urban functionalities with downtown as the main space of activities, it was expected that traffic for the use of these functionalities would be reduced. Traffic reduction was predicted to restrain downtown from growing and weaken the concentration of downtown activity. For the reorganization of existing spaces, in particular, public spaces would be changed to multi-purpose spaces in which various urban activities can be carried out using ubiquitous technologies. With the advent of U-City and the various changes of conditions, it is expected that the demand for land use and urban planning facilities would be altered by downtown and peripheries. A planning tool with a more concrete demand estimation of the future demand in individual areas of usage should be developed and it should be reflected in urban planning. Also, with the integration of functionalities so that more efficient land use will be possible, flexible designation of usage areas is necessary. Along with this, to prevent the decline of old downtown areas and provincial cities, the balanced installation of IT-related infrastructures will precede.