Bi-factor MIRT True-Score Equating for Testlet-Based Tests

이규민(Gue min Lee),Won Chan Lee,Michael J Kolen,박인용(In Yong Park),Dong In Kim,Ji Seung Yang 한국교육평가학회 2015 교육평가연구 Vol.28 No.2

Lee and Lee (2014) proposed bi-factor multidimensional item response theory model (BFM) "observed-score" equating procedures. The main purposes of this study were to develop BFM "true-score" equating procedures, and to investigate applicability of the proposed procedures with actual data. Eight equating methods (including both true- and observed-score) based on dichotomous IRT (2-parameter logistic model: 2PL), polytomous IRT (graded response model: GRM), testlet response model (TRM), and BFM were compared with target equipercentile equating. Data for this study were from the Reading Comprehension test for a large-scale state assessment program, which consisted of several passages and corresponding groups of items. True- and observed-score equating methods based upon 2PL and BFM produced similar equating results. The GRM true- and observed-score equating methods provided equating results somewhat different from others, and more similar to the target equipercentile equating. Lee와 Lee(2014) 연구는 혼합형 검사에서의 bi-factor 다차원 문항반응모형을 적용한 IRT "관찰점수" 동등화 절차를 제안하였다. 이 연구는 Lee와 Lee(2014) 연구의 추수연구로 단위검사를 대상으로 bi-factor 다차원 문항반응모형을 적용한 IRT "진점수" 동등화 절차를 제안하고, 그 적용 가능성을 실제 자료를 이용하여 탐색하고자 하였다. 이를 위해 단위검사로 구성된 대규모 독해 검사 자료를 이용하여, 2모수 로지스틱 모형(2-parameter logistic model: 2PL), 등급반응모형(graded response model: GRM), 단위검사모형(testlet response model: TRM), bi-factor 모형(bi-factor model: BFM)을 적용하였으며, 관찰점수 및 진점수 동등화를 시행하여 총 8개의 동등화 방법을 적용하고, 산출된 결과를 동백분위 동등화 결과와 비교하였다. 연구 결과, 2PL과 BFM을 적용한 관찰점수 및 진점수 동등화는 유사한 결과를 산출하였으며, GRM을 적용한 관찰점수 및 진점수 동등화 방법은 다른 방법들과 다소 차이를 보이는 결과를 산출하였고, 비교 기준이 된 동백분위 동등화 결과와 보다 유사한 결과를 보였다.

고요산혈증의 위험인자 : 아산시 지역 주민을 대상으로

김용배,장원기,황보영,김화성,안규동,이병국,이용진,이종은,이준숙,이찬구,이한정,이성수 순천향대학교 2006 Journal of Soonchunhyang Medical Science Vol.12 No.1

Objective : Serum uric acid has now been identified as a marker for a number of metabolic and hemodynamic abnormalities. The aim of this study is to evaluate risk factors which influence hyperuricemia in the citizens of Asan. Method : The study design was cross-sectional and research subjects were 1086 citizens of Asan. General characteristics, cigarette smoking, alcohol consumption, and past history were obtained by interview using a structural questionnaire. Also, we measured height, weight and blood pressure, and serum uric acid of the subjects. Results : The mean serum uric acid level was 5.27 ㎎/㎗ in men and 4.01 ㎎/㎗, in women, In the multiple logistic regression analysis, statically significant risk factors of hyperuhcemia were gender, body mass index, blood lead concentration, and serum creatinine. Conclusion : Our results suggest that gender, body mass index, blood lead concentration, and serum creatinine might be the most important risk factors of hyperurcemia. Education program as well as routine check-up for serum uric acid was highly recommended for the effective prevention of hyperuricemia.

김치유래 젖산균의 균체지방산 분석을 이용한 분류학적 연구

이정숙,정민철,김우식,이근철,김홍중,박찬선,이헌주,주윤정,이근종,안종석,박완,박용하,민태익 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.2

표준균주를 포함한 230여개의 김치유래 젖산균에 대한 균체지방산(FAMEs)을 분석하였다. FAMEs profiles는 Euclidian Distance 17.5에 의해 7개의 Major Cluster와 1개의 Single Cluster로 나뉘어졌다. 이중 A, B, C 및 Cluster는 Leuconostoc속으로 분석되어졌고, F는 Lactobacillus속으로 분석되어졌다. 그리고 E와 G cluster는 두개의 Genus가 혼재되어 나타났으며 보충적인 연구가 필요하다. 앞으로 김치유래 젖산균의 균체지방산 분석결과를 기반으로 한 데이타베이스에 95가지 탄소원을 이용하는 수치분류학적 접근방법 및 Pyrolysis Mass Spectrometry 등의 화학적 분석 방법과 분자친화적 연구를 통한 종합적 분류정보 체계가 갖추어지면 젖산균의 신속, 정확한 동정 및 연구에 활발히 이용되어질 것이다. Two hundreds and thirty lactic acid bacteria, mostly isolated from Kimchi, including type strains were sued for analysis of cellular fatty acids. The 230 test strains were recoverd in 7 major and 1 single clusters defined a Euclidian distance of 17.5. These aggregate taxa were equivalent to the genus Leuconostoc (aggregate group A, B, C and D), and the genera Leuconostoc and Lactobacillus (aggregate group G). It is concluded as evident that FAMEs (Fatty Acid Methyl Esters) profile of cell can be used as a criterion in classification of lactic acid bacterial from kimchi. Additional comparative taxonomic studies need to be carried out on well chosen representative strains to determine the most appropriate methods of value.

스포츠 용품 인터넷 쇼핑에 대한 소비자 신뢰에 관한 연구

이용찬,최종인,노선표 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.4

The purpose of the study is to learn the consumer trust of university students in internet shopping of sports commodities. The subjects were 419 university students being in school in Jun La Buk Do(Jun La province) have been surveyed. 246 male students, while 173 female. For trust rate check, "consumer trust rate during internet shopping check sheet(trust rate a=0.76)" by Lee Yong Gyoon and Lee Gyoo. Yong has been used. By using statistics program of Spsspc10.0 for data processing, results have been obtained as follows after performing technical statistics, variance analysis and regression analysis. 1. Among society and population study backgrounds, there has been difference in consumer trust according to gender(p<.05), but no difference according to family types.(p>.05) 2. Shopping path, selection criteria on shopping mall and the reason for purchase of commodities have influence on consumer trust(p<.05) 3. There has been difference in consumer trust according to career of internet use(p<.05). 4. There has been no difference in consumer trust according to hours of daily internet use(p<.05) From the results above, the conclusion is that when university students purchase sports commodities using internet, they consider the stability of the company, the scale of the shopping mall company, etc.

벼, 콩 및 채소류에 대한 Mn-54, Co-60, Zn-65, Cs-137의 토양-작물체간 전이계수

박찬걸,조용우,최용호,김국찬,이창우,이강석,이정호 대한방사선 방어학회 1991 방사선방어학회지 Vol.16 No.2

벼, 콩, 상치, 당근, 호박의 가식부위에 대하여 몇가지 토양에 있어서 토양-작물체간 Mn-54, Co-60, Zn-65, Cs-137의 전이계수를 포트 재배에 의한 방사성 추적자 흡수실험을 통하여 조사하였다. 핵종간 전이계수는 거의 모든 경우 Zn-65>Mn-54>Cs-137>Co-60의 순이었다. 콩이 벼보다 전반적으로 한 자리 정도 높은 값을 보였고 채소류의 경우에는 대체로 상치에서 가장 높고 호박에서 가장 낮은 값을 보였다. 강산성 토양에서는 약산성 토양에서보다 전이계수가 훨씬 높았다. 본 조사결과에 입각하여 한국인의 섭식경로 피폭선량 평가에 이용하기 위한 각 핵종의 전이계수치가 작물별로 제안되었다. Soil-to plant transfer coefficients of Mn-54, Co-60, Zn-65 and Cs-137 were estimated for the edible parts of the rice, soybean, lettuce, carrot, and squash grown in different soils by radiotracer uptake experiments using pot cultures. The transfer coefficients of radionuclides were n the order of Zn-65>Mn-54>Cs-137>Co-60 in most of the cases studied. The coefficients for soybean were roughly and order of magnitude higher than those for rice. Among vegetables, lettuce mostly showed the highest value and squash, the lowest. In the strongly acidic soils. From the data obtained, crop-specific transfer coefficients of the four nuclides were proposed for the use in Korean food-radiation dose assessment.

중온 침출수 재순환 혐기성 소화 시스템을 이용한 음식물류 폐기물 처리

조찬휘ㆍ이병희ㆍ이용운(Chan Hui ChoㆍByong hi LeeㆍYong Woon Lee) 유기성자원학회 2016 유기물자원화 Vol.24 No.1

본 연구에서는 침출수 재순환 시스템을 적용한 중온 혐기성소화를 이용하여 음식물류 폐기물을 분해하여 메탄가스를 생산하였다. 실험은 36℃로 유지되는 항온수조 내에 생물반응조와 침출수 저장조로 구성된 2개의 동일한 시스템(System A, System B)을 사용하였고, 생물반응조 하단 30 mm위에는 스크린이 있어 고액분리를 하여 침출수 저장조로 침출수를 이송하였다. 침출수 재순환은 매일 수행하였으며, 침출수 재순환 시에는 생물반응조 하단에서 침출수 저장조로 2.5 L를 30분간 이송한 뒤 다시 침출수 저장조에서 생물반응조 상부로 2.5 L를 30분간 주입하였다. 주입된 음식물류 폐기물은 수집되기 전 한 번 세척하였으며 반응조에 주입되기 전에 36℃로 온도를 올렸다. System A에 49.1 g VS, System B에 54.0 g VS을 2주 간격으로 투입하였다. 저해인자로 측정된 항목은 NH₄⁺-N과 염도였으며, 두 가지 항목의 농도 모두 시스템에 끼친 영향은 없는 것으로 나타났다. System A는 112일간, System B는 140일 동안 운전하였는데, 각 시스템에서 인발된 슬러지는 없었다. 음식물류 폐기물의 혐기성 소화를 통한 평균 메탄 발생량은 System A의 경우 0.439 L CH4/g VS, System B의 경우 0.368 L CH4/g VS로 나타났다. In this study, mesophilic anaerobic digestion of source separated food waste was carried out by leachate recirculation system and methane gas was produced. Two systems - system A and B were fabricated and placed within water bath to maintain 36℃. Each system was comprised of an anaerobic bioreactor and a leachate tank. Leachate in bioreactor was separated through the screen located at 30 mm above the bottom and a pump was installed to transfer collected leachate to the leachate tank. Everyday, 2.5 L of the leachate was pumped from the bioreactor to the leachate tank for 30 min and transferred leachate was pumped back to the top of the bioreactor for 30min, sequentially. Source separated food waste used for this experiment was washed by water before transferring to the laboratory. Transferred food waste was warmed to 36℃ before being fed to bioreactors. System A was fed to 49.1 g VS (Volatile Solids) and System B was fed to 54.0 g VS at every two weeks, respectively. NH₄⁺-N and salinity were monitored to see the inhibition toward anaerobic bioreaction and it was found that concentrations of these materials were not high enough to affect the bioreaction. Although the food waste was fed biweekly for 112 days and 140 days at system A and B, respectively, there was no sludge withdrawal from each system. Average methane productions rates were 0.439 L CH4/g VS and 0.368 L CH4/g VS for system A and B, respectively.

지난 2년간의 학회지 "신경정신의학" 심사 평가보고

김찬형,김세주,김도관,김성곤,박원명,송동호,박용천,이영문,오강섭,정영철,이상열,김주한,이동영,이헌정,함병주,김율리,김문두,김정진,이강욱,천근아,김재진,홍진표,홍승철 大韓神經精神醫學會 2007 신경정신의학 Vol.46 No.6

우리나라 논 관개용 지하수 수질 특성

김진호,조광래,임수정,이경자,경기천,엄미정,김희권,김찬용,이영한,이신찬,윤순강 한국환경농학회 2003 한국환경농학회지 Vol.22 No.4

This study was carried out to evaluate the status of the groundwater quality for paddy fields irrigation in Korea. Water samples were collected at 130 sites throughout the country. Samples were collected at three seasons-April, July and October-in 2000. According to our survey, the groundwater was found to be suitable for irrigation purpose. Average EC was shown 0.286 dS/m. Nitrate-nitrogen and Cl^(-) concentration was 5.6 ㎎/L, 32.95 ㎎/L which satisfied the Korean Standards for Irrigation Water. Nitrate-nitrogen concentration in each province was shown as following orders: Jeju (11.17 ㎎/L) > Chungnam (8.16 ㎎/L) > Gyeongbuk (6.64 ㎎/L) > Gyounggi (5.91 ㎎/L) > Chungnam (4.95 ㎎/L) > Gyeongnam (3.91 mgk) > Jeonbuk (3.50 ㎎/L) > Jeonnam (3.27 ㎎/L) > Gangwon (2.91 ㎎/L). The concentration by sampling seasons were October (6.62 ㎎/L) > July (5.88 mg&) > April (4.78㎎/L). As the soil of Jeju Province is usually derived from volcanic ash soils mainly used for upland drops, it may influence the nitrate-nitrogen concentration of groundwater. The amount of rainfall also influence the water quality. But the COD_(Cr), were shown April (3.17㎎/L) > July (2.91 ㎎/L) > October (2.40 ㎎/L), it is highly related in the basal dose of organic matter fertilizers. This study demonstrated that groundwater quality was suitable for irrigation, but continuous monitoring is recommended for agricultural policy and developing OECD agricultural environment indicators.

大田市 共同住宅 再建築事業 施行에 따른 物理的 變化 特性에 관한 硏究

이건호,김용찬 牧園大學校 建築·都市硏究센터 1997 建築·都市環境硏究 Vol.5 No.-

With the progress of urbanization, industrialization and rapid increase in population, our country has been short of urban infrastructures, facilities and housing absolutely. A reconstruction is in force for only benefits due to high density development in low density residential area. Moreover it is inclined to exceed the housing supply than recovery of urban function or betterment of residential environment. So residential environments (like a right to enjoy sunshine, urban scenery, traffic jam, etc.) are getting worse, because they construct high-rise and high-density buildings without infrastructure. This study started to find and solve the reconstruction problems and exhibit the direction of prospective reconstruction with analysis and arrangement of quality between reconstruction and existing urban improvement systems with Tae-Jon as the study object. And this study tried to exhibit the betterment plan of reconstruction characters in view of urban improvement.

구-막대 시스템에서 CDM을 사용한 강인한 제어기 설계

이호기,박용식,정찬수 崇實大學校 1999 論文集 Vol.29 No.1

All the controller design problem for linear time invariant dynamic system boils down to proper selecting the characteristic polynomials and numerator polynomials for concerned input-output relations. The propel selection of the characteristic polynomial is not so difficult, if only stability and response are to be satisfied, but it becomes complicated when robustness issue is added. The CDM could be a solution to this problem. CDM which is developed by Lipatov's conditions for stability and Kessler's standard form is easy to process of the controller design, especially it is more useful when the specifications are the settling time, rising time and overshoot. In this paper was used CDM design a simple but robust controller of the ball and beamsystem. The ball and beam system is highly nonlinear system. And it's linear transfer function used to design the controller. But CDM proved to be a solution to design even if there are some uncertainties like this linearized ball and beam system by simulations.