• 제목/요약/키워드: The values

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An Improvement on Estimation for Causal Models of Categorical Variables of Abilities and Task Performance

  • Kim, Sung-Ho
    • Communications for Statistical Applications and Methods
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    • 제7권1호
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    • pp.65-86
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    • 2000
  • The estimates from an EM when it is applied to a large causal model of 10 or more categorical variables are often subject to the initial values for the estimates. This phenomenon becomes more serious as the model structure becomes more serious as the model structure becomes more complicated involving more variables. In this regard Wu(1983) recommends among others that EMs are implemented several times with different sets of initial values to obtain more appropriate estimates. in this paper a new approach for initial values is proposed. The main idea is that we use initials that are calibrated to data. A simulation result strongly indicates that the calibrated initials give rise to the estimates that are far closer to the true values than the initials that are not calibrated.

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충남 웅천에서 관측된 강수의 산성도 연구 (Acidity Analysis of Precipitation Occurred at Woongchon, Choongnam)

  • 이근준;정용승
    • 한국대기환경학회지
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    • 제12권2호
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    • pp.179-187
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    • 1996
  • Sampling of precipitation occurred at Woongchon in Choongnam from the period between May 1994 and April 1995 was made, and analysis on the data was carried out on observed pH values of the precipitations. It was found that weighted mean pH values were .sim. 4.8 and that acid rain occurred at the site of the Yellow Sea's coastal area. The results agree well with the earlier observations made at other sites of a background monitoring network. The annual values observed at the background monitoring sites were too low in comparison with the mean pH values (5.3 .sim. 5.9) obtained from urban stations of the Ministry of Environment. It was observed that values of pH in rain water often changed with time during the event of precipitation, and the low values usually depended on an airflow and a cyclone that originated in the source region.

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A Study of the Ionic Association of the Substituted N-Methyl Pyridinium Iodide (II), 4,N-Dimethyl Pyridinium Iodide in Ethanol-Water Mixture

  • Kwun, Oh-Cheun;Jee, Jong-Gi
    • Bulletin of the Korean Chemical Society
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    • 제6권1호
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    • pp.37-40
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    • 1985
  • The electrical conductance and UV absorbance of 4,N-dimethyl Pridinium Iodide (NDMPI) were measured in the ethanol volume percentage, 95, 90, 80 and 60 of an ethanol-water mixture at 15, 25, 35 and $45^{\circ}C$. Ionic association constants(K) of NDMPI were evaluated in accordance with a combined method of conductance UV absorbance. The ion size parameter (${\gamma}_{\pm}$) and dipole momemt (${\mu}_{A+D-}$) of NDMPI were obtained from the values of K and dielectric constant. The ${\mu}_{A+D-}$- values were in good agreement with the values of transition moment(${\mu}_{mn}$) which is calculated form the UV peak values. The large negative values of the electrical enthalpy (${\Delta}H_{el}^{\circ}$) and entropy (${\Delta}H_{el}^{\circ}$ ) have proved that NDMPI had a positive hydration. The positive values of entropy (${\Delta}S^{\circ}$) means the formation of NDMPI ion goes with dehydration.

청소년의 성지식과 성가치관 및 성관심간의 관계 (Relationship between Adolescents' Sexual Knowledge and their Sexual Values and Interests)

  • 민하영;이영미;김경화
    • 대한가정학회지
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    • 제44권3호
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    • pp.171-179
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    • 2006
  • The purpose of this study was to clarify the relationship between the sexual knowledge of adolescents and their sexual values and interests with regards to gender and grade. The case subjects were 272 middle and high school students in Keoungbok 154 boys and 118 girls, who completed the study questionnaire. Statistical techniques used for the investigation were crosstabs, t-test, Pearson's partial correlation and hierarchical multiple regression. The results of this study were as follows: (1) There were gender and grade differences in the adolescents' sexual knowledge and their sexual values and interests. (2) The adolescents' sexual knowledge showed a positive correlation with their own sexual values and interests. (3) The adolescents' sexual interests were a stronger predictor of sexual knowledge than sexual values, gender or grade.

도시청소년의 주거가치와 주거만족도 (Housing Values and Housing Satisfaction from the Perspective of Urban Adolescents)

  • 김미희;정미영
    • 한국주거학회논문집
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    • 제14권3호
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    • pp.9-18
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    • 2003
  • This study is designed to explore the relationship between the level of housing satisfaction and housing values, as well as family characteristics and characteristics of residence. Questionnaires are administered to 526 adolescents from the four residential areas in Kwangju. Most of the adolescents are satisfied with their housing environment, especially indoors, however, they show a lower level of satisfaction toward the appearance and organization of the unit plan. It is found that the level of the safety, comfortability and social values predicted a meaningful variance in the level of housing satisfaction. Those with a higher degree of safety and social values tend to be associated with stronger housing satisfaction, whereas those with lower comfortability values are more associated with stronger housing satisfaction. Groups with higher household incomes are more likely to be satisfied with their housing environment. Groups living within a younger and larger house are more likely to be satisfied with their housing environment. Also, owners tend to show a stronger degree of housing satisfaction than renters.

Gas Phase Proton Affinity, Basicity, and pKa Values for Nitrogen Containing Heterocyclic Aromatic Compounds

  • Hwang, Sun-Gu;Jang, Yun-Hee;Chung, Doo-Soo
    • Bulletin of the Korean Chemical Society
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    • 제26권4호
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    • pp.585-588
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    • 2005
  • Bipyridine and its derivatives have been widely used as the ligands in transition metal complexes. The proton affinities of pyridine derivatives were calculated using an ab initio quantum mechanical method (B3LYP with various double zeta and triple zeta basis sets) in combination with the Poisson-Boltzmann continuum solvation model. Van der Waals radii of the atoms in the heterocyclic rings for the solvation energy calculation were set to values determined to reproduce the $pK_a$ values of guanine and oxoguanine derivatives and that of chlorine was optimized to reproduce the experimental values of relating compounds. The $pK_a$ values for the heterocyclic ring compounds were in agreement with the experimental values with a mean unsigned error of 0.45 $pK_a$ units.

한국어 전설 모음의 포먼트 전이 형태 (Formant Transition Shapes of Korean Front Vowels)

  • 오은진
    • 말소리와 음성과학
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    • 제5권4호
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    • pp.195-200
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    • 2013
  • This study investigates formant transition shapes of Korean front vowels produced by native speakers of Seoul Korean. Sixteen speakers (eight male and eight female speakers) produced [pVt] syllables where the vowels were [i, e, ɛ]. F1, F2, and F3 transition shapes were estimated by presenting formant values at 11 points by dividing the vowel duration into 10 different time intervals. The results indicated that the male and female speakers overall demonstrated similar formant transition shapes and measurement points arriving at the maximum and minimum formant values for the three front vowels. As for the vowels [e] and [ɛ], both male and female speakers showed similar formant values across the 11 measurement points and similar measurement points arriving at the maximum and minimum values, indicating that the two Korean vowels have been merged not only in the steady-state formant values, but also in the dynamic transition shapes.

청소년의 환경가치에 대한 연구 -서울 시내 중.고등학생을 사례로 (A Study on the Environmental Values of Students at the Level of Secondary Schools in Seoul)

  • 주형선;김종욱
    • 한국환경교육학회지:환경교육
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    • 제14권1호
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    • pp.81-91
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    • 2001
  • The importance of values has been emphasized in the aspect of the cause and solution of environmental problems. It is suggested that educational programs designed to increase environmental concern should be focused on ecocentric values. To do this, it is a prerequisite to understand the level of learners'environmental value. This study measured the level of environmental values of students in secondary schools in Seoul and identified relationship with its variables such as belief, the degree of identification, and environmental experience. We discussed on how to improve the environmental education in the aspects of fostering ecocentric values from the results of this study.

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THE TRUE METABOLIZABLE ENERGY VALUES OF SOME SELECTED FEEDSTUFFS OF BANGLADESH

  • Huque, Q.M.E.;Kosaka, K.
    • Asian-Australasian Journal of Animal Sciences
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    • 제9권5호
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    • pp.571-575
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    • 1996
  • An experiment was conducted to measure the true metabolizable energy (TME) values of seven major poultry feed ingredients, two feed concentrates and one randomly collected layer mixed feed prepared from the available feed ingredients. The results of this study were the most thorough evaluation of the TME content of some selected common feed ingredients of Bangladesh. The observed TME values of some feed ingredients were very close to the values of different origins of feed ingredients. But the TME values measured in mixed layer feed were very low which could not support the standard requirement of laying birds. There values will be of assistance in describing the energy content of the most common available feed ingredients of Bangladesh.

Effect of horizontal at rest pressure (Po) on elastic modulus from pressuremeter testing

  • Alzubaidi, Radhi M.
    • Geomechanics and Engineering
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    • 제17권3호
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    • pp.247-252
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    • 2019
  • Modulus of deformation of soil is an essential parameter used for design analysis of foundations, despite its importance; little attention is paid to developing empirical models for predicting the sensitivity of deformation moduli to other parameters that obtained from the pressuremeter tests. Various methods of analysis used to predict the horizontal at rest pressure from pressuremeter testing ($P_o$), these values showed distinctive variations, five methods used to evaluate the values of horizontal at rest pressure, these values been used to evaluate the modulus of elasticity using three methods of analysis. The values of modulus showed distinctive increase when the values of horizontal at rest pressure increase for the same pressuremeter test, these increases may reach to 65%. This sensitivity of the moduli to values of horizontal lead the author to propose some reliable methods of analysis for both the horizontal at rest pressure and the modulus of deformation from pressuremeter testing.