• 제목/요약/키워드: levels of development

검색결과 7,132건 처리시간 0.053초

The Acquisition of the English Locative Alternation by Korean EFL Learners: What Makes L2 Learning Difficult?

  • Kim, Bo-Ram
    • 영어어문교육
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    • 제12권4호
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    • pp.31-68
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    • 2006
  • The present research investigates the acquisition of the English locative alternation by Korean EFL learners, which poses a learnability paradox, taking Pinker's framework of learnability theory as its basis. It addresses two questions (1) how lexical knowledge is represented initially and at different levels of interlanguage development and (2) what kinds of difficulty Korean learners find in the acquisition of English locative verbs and their constructions. Three groups of learners at different proficiency levels with a control group of English native speakers are examined by two instruments: elicited production task and grammaticality judgment task. According to different levels of proficiency, the learners exhibit gradual sensitivity to a change-of-state meaning and obtain complete perception of the meanings of locative verbs (manner-of-motion and change-of-state) and their constructions. Overgeneralization errors are observed in their performance. The errors are due to misinterpretations of particular lexical items in conjunction with the universal linking rules. More fundamental cause of difficulty is accounted for by partial use of learning mechanisms, caused by insufficient L2 input.

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Comparison of the Properties of Wheat Flours Supplemented with Various Dietary Fibers

  • Lee, Hyun-Ju;Shin, Mal-Shick
    • Food Science and Biotechnology
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    • 제15권5호
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    • pp.746-751
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    • 2006
  • The effects of resistant starch (RS) and non-starch polysaccharide (NSP) addition on the properties of hard wheat flour were investigated. Total dietary fiber (TDF) levels of various NSP ranged from 78.3-100.0%, but TDF and RS levels of autoclaved RS3 and cross-linked RS4 were 16.1 and 35.0% and 13.2 and 90.9%, respectively. DF-supplemented flour increased swelling power, but RS4-supplemented flour exhibited the lowest it. Solubility increased with the addition of pectin and RS3, but decreased with the addition of cellulose and RS4. RS-supplemented flour had increased lightness (L), but decreased values of redness (a) and yellowness (b). RS3 and pectin increased the dough development time, but RS4, cellulose, and chitosan decreased it. The water absorptions of pectin- and RS4-supplemented flours increased, however the dough stability decreased. The initial pasting temperatures of RS- and NSP-supplemented flours increased regardless of amount added, but the maximum peak viscosity decreased for all except the pectin-supplemented flour.

아동의 자아탄력성과 사회적 지지가 시험불안 및 학교적응에 미치는 영향 (The Effects of Children's Ego-Resilience and Social Support on Exam Anxiety and School Adjustment)

  • 박정희;박정미
    • 아동학회지
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    • 제31권6호
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    • pp.125-134
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    • 2010
  • The aim of this paper is to examine the effects of children's ego-resilience and social support on exam anxiety and school adjustment. The subjects of this study were 534, $5^{th}$ and $6^{th}$ grade students (275 boys and 259 girls) from the Pusan area. The results of this study revealed that the levels of Ego-resilience and social support correlated negatively with exam anxiety, and positively with school adjustment. Therefore the more ego-resilience and social support children felt that they had, the lower the levels of exam anxiety they experience, and the higher their levels of school adjustment. The influence of ego-resilience on exam anxiety was higher than that of social support and the influence of ego-resilience on school adjustment was similar to that of social support. The implications of the present study were also discussed.

Changes of blood pressure and Hematological changes induced by exposure of low- and high-level lead in the rats

  • Kyeongseok Yoo;Suhyoung Yoon;Jaewoong Lim;Lee, Choongjae;Jaehoon Cheong
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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    • pp.144-144
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    • 1998
  • The physiological responses caused by exposure of high- and low-level lead exhibit different phase. Low-level lead continuous hypertension, but high-level lead can in the development of hypertension. In this study it was tested which difference can be caused as lead levels and, if it can be caused, whether hematological changes are related with the hypertensive effects induced by different levels of lead exposure was tested. Lead intoxication in male SD rats was induced by exposure through drinking water containing 50, 200 and 1000 ppm lead (as lead acetate). The animals of control group was supplied drinking water containing sodium acetate ad libitum. The number of each animal group was 10. Systolic blood pressures were measured in the unanesthetized state by the tail-cuff technique at 0, 3, 7 and 16 weeks. RBC, WBC, MCV, hemoglobin, hematocrit and whole blood viscosity levels were examined.

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PYE [2-(1-pyrenyl)ethyldimethylsilylated silica] Column HPLC and HR-GC-(micro) ECD in the Accurate Determination of Toxic Co-planar PCBs and Polybrominated Diphenyl Ethers (PBDEs)

  • Kannan, Narayanan;Hong, Sang-Hee;Oh, Jae-Ryoung;Yim, Un-Hyuk;Li, Donghao;Shim, Won-Joon
    • Bulletin of the Korean Chemical Society
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    • 제26권4호
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    • pp.529-536
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    • 2005
  • Measurement of toxicologically relevant polychlorinated biphenyl (PCB) congeners such as non-ortho(IUPAC#) 77, 81, 126, 169 and mono-ortho 105, 114, 118, 123, 156, 157, 189 and di-ortho 170, 180 and polybrominated diphenyl ethers (PBDEs) such as 47, 66, 85, 99, 100, 138, 153, 154 in environmental samples become almost mandatory in several countries now. However, most of the available methods involve expensive instrumentations such as HRGC-HRMS or ECNI-LRMS, apart from expensive extraction and clean-up (with large volume of solvents) steps. A method has been devised combining the analytical separation power of PYE [2-(1-pyrenyl)ethyldimethysilylated silica] column HPLC and high-resolution gas chromatographic techniques including micro-electron capture detection (ECD) and two dimensional gas chromatograpy-ECD techniques to determine these eco-toxic substances at parts-per-trillion (ppt) levels. This combination resolves co-elution of congeners that occur in disproportionate ratios (e.g. CB-110 and -77) and allows accurate congener-specific determination of target compounds. This method is cost effective as it requires only hexane, that in small quantities (10 mL) and GC-ECD. The elution and analysis time are optimized to less man hours. This method is effectively utilized in the analysis of co-planar PCBs and PBDEs from archived solvent extracts of samples previously analyzed for pesticides and PCBs. Structure based separation of contaminant classes improves GCECD determination at ppt levels.

Comparison of MBA and HPLC Post-column Oxidation Methods for the Quantification of Paralytic Shellfish Poisoning Toxins

  • Yu, Hongsik;Lim, Keun Sik;Song, Ki Cheol;Lee, Ka Jeong;Lee, Mi Ae;Kim, Ji Hoe
    • Fisheries and Aquatic Sciences
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    • 제16권3호
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    • pp.159-164
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    • 2013
  • The mouse bioassay and high performance liquid chromatography (HPLC) post-column oxidation method are different methods of quantifying paralytic shellfish poisoning toxins. In this study, we compared their ability to accurately quantify the toxicity levels in two types of field sample (oysters and mussels) with different toxin profiles for routine regulatory monitoring. A total of 72 samples were analyzed by both methods, 44 of which gave negative results, with readings under the limit of detection of the mouse bioassay ($40{\mu}g/100g$ saxitoxin [STX] eq). In 14 oysters, the major toxin components were gonyautoxin (GTX) 1, -2, -3, -4, -5, decarbamoylgonyautoxin-2 (dcGTX2), and decarbamoylsaxitoxin (dcSTX), while 14 mussels tested positive for dcSTX, GTX2, -3, -4, -5, dcGTX2, neosaxitoxin (NEO), STX, and dcSTX. When the results obtained by both methods were compared in two matrices, a better correlation ($r^2=0.9478$) was obtained for mussels than for oysters ($r^2=0.8244$). Additional studies are therefore needed in oysters to investigate the differences in the results obtained by both methods. Importantly, some samples with toxin levels around the legal limit gave inconsistent results using HPLC-based techniques, which could have a strong economic impact due to enforced harvest area closure. It should therefore be determined if all paralytic shellfish poisoning toxins can be quantified accurately by HPLC, and if the uncertainties of the method lead to doubts regarding regulatory limits.

Nutritional and Hormonal Induction of Fatty Liver Syndrome and Effects of Dietary Lipotropic Factors in Egg-type Male Chicks

  • Choi, Y.I.;Ahn, H.J.;Lee, B.K.;Oh, S.T.;An, B.K.;Kang, C.W.
    • Asian-Australasian Journal of Animal Sciences
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    • 제25권8호
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    • pp.1145-1152
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    • 2012
  • This experiment was conducted with male chicks to investigate the influence of hormones and nutrients on the development of fatty liver syndrome (FLS) as well as the effects of dietary lipotropic factors on hepatic fat accumulation and lipogenic enzyme gene expression. A total of two-hundred sixteen 4-wk-old Hy-Line male chicks were divided into six groups and fed an experimental diet (T1, low-energy diet with low levels of lipotropic factors; T2, high-energy diet with low levels of lipotropic factors; T3 and T5, low-energy diet with high levels of lipotropic factors; T4 and T6, high-energy diet with high levels of lipotropic factors) for six weeks. The chicks in T5 and T6 groups were treated with intramuscular injections of estradiol benzoate for three days prior to biopsy and clinical analysis of FLS. Chicks treated with estrogen had significantly greater liver weights than untreated chicks. The abdominal fat contents were increased in chicks consuming high-energy diets as compared to those consuming low-energy diets. Treatment with estrogen significantly increased the concentrations of serum cholesterol, triacylglycerol and phospholipid (p<0.05). The hepatic triacylglycerol levels were tenfold higher in the estrogen treated chicks than in the untreated chicks. There were no significant differences in malondialdehyde levels between the treatment groups. Estrogen treatment dramatically increased the levels of fatty acid synthetase, acetyl-CoA carboxylase and ApoB mRNA. The results indicated that treatment with exogenous estrogen in growing male chicks induced hepatic fat accumulation, which might be partially due to increased lipogenic enzyme gene expression.

준설토 활용과 환경기준 (Environmental Standards for Beneficial Uses of Dredged Materials)

  • 윤길림;이찬원;정우섭
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2008년도 추계 학술발표회
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    • pp.247-258
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    • 2008
  • Environmental standards for beneficial uses of dredged materials are proposed. Even though chemical analysis of ocean sediments are carried out frequently, their analyses results were not interrelated with the effects of biological lives due to a shortage of biological data. These facts have resulted in difficulty to develope Korean's standards of recycling dredged materials. This paper first searched existing current foreign standards, analyzed local contaminated ocean sediment data, identified their main chemical components of contaminants, and then compared with clean-up standards of sediments consisting of lower and higher levels. From these analysis, new environmental standards considering Korean domestic circumstances are proposed. It is judged that new standards are appropriate to both Korean national sedimental environments and economically recycling aspects because environmental standard levels proposed are higher than background levels of sediments in Korean and foreign standards.

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청소년의 성취동기와 관련된 변인들 : 가정의 사회경제적 지위, 어머니의 기대 및 정서적 지지와 청소년의 자아존중감 (Correlates of Adolescent Achievement Motivation : Socioeconomic Status, Maternal Expectations and Emotional Support, and Adolescent Self-Esteem)

  • 이운경;도현심
    • 아동학회지
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    • 제26권3호
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    • pp.43-59
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    • 2005
  • A sample of 578 adolescents responded to self-report questionnaires. Results showed that parental education levels and occupation and adolescent perceptions of their socioeconomic status were positively related to maternal expectations. Adolescent perceptions of their socioeconomic status were related to maternal emotional support and adolescent self-esteem. Adolescent achievement motives were positively related to parental education levels and adolescent perceptions of their socioeconomic status. Maternal expectations/emotional support and adolescent perceptions of their socioeconomic status were positively related to adolescent achievement motivation. Maternal expectations played a mediating role between parental educational levels and adolescent perceptions of their socioeconomic status and adolescent achievement motives. Maternal emotional support and adolescent self-esteem played mediating roles between adolescent perceptions of their socioeconomic status and achievement motives.

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Determining the complexity level of proceduralized tasks in a digitalized main control room using the TACOM measure

  • Inseok Jang;Jinkyun Park
    • Nuclear Engineering and Technology
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    • 제54권11호
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    • pp.4170-4180
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    • 2022
  • The task complexity (TACOM) measure was previously developed to quantify the complexity of proceduralized tasks conducted by nuclear power plant operators. Following the development of the TACOM measure, its appropriateness has been validated by investigating the relationship between TACOM scores and three kinds of human performance data, namely response times, human error probabilities, and subjective workload scores. However, the information reflected in quantified TACOM scores is still insufficient to determine the levels of complexity of proceduralized tasks for human reliability analysis (HRA) applications. In this regard, the objective of this study is to suggest criteria for determining the levels of task complexity based on logistic regression between human error occurrences in digitalized main control rooms and TACOM scores. Analysis results confirmed that the likelihood of human error occurrence according to the TACOM score is secured. This result strongly implies that the TACOM measure can be used to identify the levels of task complexity, which could be applicable to various research domains including HRA.