• Communications of Mathematical Education
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• v.25 no.1
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• pp.245-259
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• 2011

In this study, the instrument of mathematical creative problem solving ability test were considered the differences between Korean and American sixth grade students in mathematical creativity ability and mathematical thinking ability. The instrument consists of 9 items. The participants for the study were 212 Korean and 148 American students. SPSS were carried out to verify the validities and reliability. Reliabilities(Cronbach ${\alpha}$) in mathematical creativity ability is 0.9047 and in mathematical thinking ability is 0.9299 which were satisfied internal validity evaluation on the test items. Internal validity were analyzed by BIGSTEPS based on Rasch's 1-parameter item response model. The results of this study can serve as a foundation for understanding the Korean and American students differences in mathematical creativity ability and mathematical thinking ability. Especially we get the some informations on mathematical creativity ability for American's fifth grade to seventh grade students.

• Journal of the Korean Geotechnical Society
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• v.17 no.6
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• pp.15-24
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• 2001

In order to evaluate undrained shear strength of clayey soils using Piezocone Penetration Test (CPTu), piezoncone factor is utilized. Commonly, piezoncone factors determined by empirical basis were preferred, which were established by correlation between measurements of piezocone test and undrained strengths obtained from other shearing tests. However, previous studies on the empirical piezocone factors were site-specific and there have been no systematic investigations on the effect of both engineering characteristics of clayey soils and soil non-homogeneity on the piezocone factor. Accordingly, the direct application of the previous results to Korean clayey soils without verification may be inappropriate. In this study, empirical piezocone factors are evaluated by comparing 46 CPTu results of 10 test sites with undrained shear strength obtained from Field Vane Test (FVT) and laboratory triaxial tests. Their reliabilities are investigated by the comparison with the previous piezocone factors and the deviation of data distribution from the mean values. And the effects of referencing test methods and typical engineering characteristics of clayey soils such as overconsolidation ratio (OCR) and plastic Index (I$_{p}$) are examined. Because piezocone factors obtained for various soil conditions are widely distributed, it is not appropriate to use the mean value as a representative. Instead, it is recommended to apply the piezocone factors with OCR, which is found to be a major factor in deriving piezocone factor. The necessitated piezocone factors are presented.d.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.1
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• pp.105-109
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• 2010

While numerous information services are provided on the Web as a core infrastructure of information society, semantic services using the Semantic Web technologies still stay deployed number and application range. This situation would be mainly originated from the failure of securing reliability to the user. Thus, this paper introduces an evaluation method for measuring reliabilities of the semantic services comparatively. To measure the reliability of the compared systems, the observer assesses 'precision in task performance' as a quantitative analysis and 'reliability of expectation-result' as a qualitative analysis described by the test persons. On the other hand, the test person should rate the functional reliability and reliability of the served information on the vector graph by himself with a scale from 0 to 5. Experimental results show that assessment by the observer is very similar to rating value by test persons, and that the accuracy of the served information has a close effect on the functional reliability. Through this paper, we can verify the essential factors for evaluating the reliability of semantic service systems. These are functional reliability and reliability of served information resulting from function execution. In particular, it has been proven that the reliability of the semantic information services largely influences the "Quality in Use" and therefore determines the major factors of the semantic service reliability.

• Ocean and Polar Research
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• v.36 no.4
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• pp.487-494
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• 2014

Deep-seabed test miner operated by a self-propelled mining system moving on soft soil is an essential device to secure floating and towing performances. The performances of the tracked vehicle are seriously influenced by noise factors such as the shear strength of the seafloor, bottom current, seafloor slope, speed of tracked vehicle, reaction forces of flexible hose, steering ratio, etc. Due to uncertainties related to noise factors, the design of a deep-sea manganese nodules test miner that satisfies target reliabilities is difficult. Therefore, reliability-based design optimization (RBDO) is required to guarantee system reliability under circumstances where uncertainties related to noise factors prevail. Among noise factors, the bottom current, a bimodal distribution, is censored due to the observation limit of measurement devices. Therefore, estimated distribution of the bottom current is inaccurate without considering these characteristics and the result of RBDO cannot be guaranteed. In this paper, we define censored data as unknown values over the limit of observation. If this data is estimated by using Akaike information criterion (AIC) that cannot consider the characteristics of censored data, the distribution of estimated data cannot guarantee accurate reliability. Therefore, censored AIC that can consider the characteristics of data is used to estimate accurate distribution of the bottom current. Finally, RBDO, under circumstances where uncertainties related to noise factors combined censored data are present, is performed on the mobility of a deep-sea manganese nodules test miner.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.467-474
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• 2017

To investigate the intra-rater absolute reliabilities and validity of the Figure of-Eight Walk test (F8WT) in patients with chronic stroke. A total of 36 subjects with chronic stroke participated in this study. The inter-rater reliability of F8WT was calculated using intra-class correlation coefficients($ICC_{2,1}$). Moreover, we used the standard error measurement (SEM) and the small real difference (SRD) to examine the absolute reliability indices. The validity was demonstrated by a spearman correlation of F8WT with Postural Assessment Scale for Storke(PASS) and Trunk Impairment Scale(TIS). The inter-rater reliability of F8WT was excellent; ICC2,1=0.95(0.91~0.97), acceptable SEM=1.02, and SRD=2.82. F8WT were also found to be significantly associated with PASS(r=-0.82) and TIS(r=-0.85). Therefore, F8WT is a reliable measurement tool and is correlated well with stroke-impairments, such as postural and trunk control. F8WT will be a useful tool in evaluating the walking performance of subjects with chronic stroke.

• Journal of the Microelectronics and Packaging Society
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• v.15 no.2
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• pp.37-45
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• 2008

In this study, reliabilities of Cu (60 um)/SnAg (20 um) double-bump flip chip assemblies were investigated for the flip chip interconnections on organic substrates with 100 um pitch. After multiple reflows at $250^{\circ}C\;and\;280^{\circ}C$, bump contact resistances were almost same regardless of number of reflows and reflow temperature. In the high temperature storage test, there was no bump contact resistance change at $125^{\circ}C$ up to 2000 hours. However, bump contact resistances slightly increased at $150^{\circ}C$ due to Kirkendall voids formation. In the electromigration test, Cu/SnAg double-bump flip chip assemblies showed no electromigration until about 600 hours due to reduced local current density. Finally, in the thermal cycling test, thermal cycling failure mainly occurred at Si chip/Cu column interface which was found out the highest stress concentration site in the finite element analysis. As a result, Al pad was displaced out under thermal cycling. This failure mode was caused by normal compressive strain acting Cu column bumps along perpendicular direction of a Si chip.

• Journal of muscle and joint health
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• v.1 no.1
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• pp.31-47
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• 1994

The purposes of this research are to examine the effects of muscle relaxation to the rheumatoid arthritis patients' physiological, psychological, and social adaptation, and to verify that the technique Is an effective tool for improving the patients' adaptation. This research utilized a qusi-experimental design that compares the pre-experiment measures and the post-experiment measures. The subjects of this study were 37 out-patients who were diagnosed for rheumatoid arthritis in P university hospital and K clinic between September 12, 1993 and November 30, 1993. The experimental group consisted of patients treated on Monday, Wednesday and Friday. The control group consisted of patients treated on Tuesday, Thursday and Saturday The pre-experimental survey utilized the following tools. The physiological adaptation was measured by a graphic rating scale for pain and activity of daily living. The psychological adaptation was measured by Zung's depression scale and Rosenberg's self-esteem scale : and the social adaptation was measured by Derogatis' psychosocial adjustment scale. The experimental group received muscle relaxation treatment for 15 minutes per day for the period of 2 weeks, the control group received no treatment and had quiet time. The post-experiment measurement was carried out similar to the pre-experiment survey, SPSS $PC^+$ is used to analyze the collected data. The reliabilities of the measurement tools were examined by Cronbach's ${\alpha}$ coefficients. The homogeneities between the experimental and control groups were tested by t-test and chi-square test, hypotheses were tested by t-test. This research found that the general characteristics between the groups were statistically homogenious. The physiological, psychological, and social adaptation between the groups in the pre-experimental survey were also statistically homogenious. The results of this research can be summarized as follows : 1. Concerning the Physiological adaptation, the experimental group showed a statistically lower pain score than the control group. Thus, muscle relaxation was effective to relieve the pain of rheumatoid arthritis patients (t=-2.95, p=.006). 2. Concerning the psychological adaptation, the experimental group showed a statistically lower depression score than the control group. Thus, muscle relaxation was effective to reduce the patient's depression(t=-4.00, p=.001). 3. Concerning social adaptation, the experimental group showed a statistically higher score for the health maintenance and disease control than the control groups. Thus, muscle relaxation was effective for the health maintenance and disease control (t=2.09, p=.004). This research showed that the muscle relaxation is a nursing intervention that can promote the physiological, psychological and social adaptation of the rheumatoid arthritis patients in terms of short-term and cognitive changes. However, more fundomental changes in behavior and long-term physiology could not be found through such a short-term relaxation treatment.

• The Journal of the Korea Contents Association
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• v.14 no.10
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• pp.628-638
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• 2014

The aim of this study was to explore the reliability and validity of the Korean version of the Recovery Assessment Scale in psychiatric patients. The original RAS was translated into Korean and the content was verified through back-translation procedures. This study included 142 patients who had chronic mental illness and were aged 18 or older. The subjects were assessed by using RAS-K, the 12-item Dispositional Hope Scale(DHS), the 28-item Mental Health Recovery Measure(MHRM), the 32-item Behavior and Symptom Identification Scale (BASIS-32). In the reliability test, Crobach's a coefficient and test-retest reliabilities were 0.92 and 0.79, respectively, indicating that the RAS-K has good internal consistency. In the analysis of the concurrent validity of the RAS-K, there were significant correlations between the RAS-K and DHS(r=.675, p<0.01), and between the RAS-K and MHRM(r=.816, p<0.01), but lower correlations with symptoms and clinician-related measures of psychiatric functioning. Factor analysis resulted in a five factor solution accounting for 62.476% of the common variance. Our study indicates that the RAS-K is an appropriate instrument to assess recovery in Korean psychiatric patients.

• Journal of the Microelectronics and Packaging Society
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• v.18 no.1
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• pp.55-59
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• 2011

Folding endurance, bending fatigue and monotonic tensile tests of 4 kinds of Cu foil on flexible substrate was performed to investigate the relationship between folding or bending endurances and tensile characteristics. The repeated 5.3 or 2.0% strain was applied to Cu foil in folding endurance test or bending fatigue test while monitoring the electrical resistance. Elastic modulus, yield strength, ultimate tensile strength, ductility, and toughness were obtained by monotonic tensile test on the same samples. The Cu foil with higher toughness and ductility showed higher reliabilities in folding or bending fatigue. However, elastic modulus and yield strength did not show any relationship with folding and bending reliability. This is because the failures of Cu foil by folding or bending fatigue were closely related to the fracture energy of metal.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.8
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• pp.1073-1082
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• 2012

We first sought to clarify the effects of discounted rate, survival rate, and lactation persistency as a component trait of the selection index on net merit, defined as the first five lactation milks and herd life (HL) weighted by 1 and 0.389 (currently used in Japan), respectively, in units of genetic standard deviation. Survival rate increased the relative economic importance of later lactation traits and the first five lactation milk yields during the first 120 months from the start of the breeding scheme. In contrast, reliabilities of the estimated breeding value (EBV) in later lactation traits are lower than those of earlier lactation traits. We then sought to clarify the effects of applying single nucleotide polymorphism (SNP) on net merit to improve the reliability of EBV of later lactation traits to maximize their increased economic importance due to increase in survival rate. Net merit, selection accuracy, and HL increased by adding lactation persistency to the selection index whose component traits were only milk yields. Lactation persistency of the second and (especially) third parities contributed to increasing HL while maintaining the first five lactation milk yields compared with the selection index whose only component traits were milk yields. A selection index comprising the first three lactation milk yields and persistency accounted for 99.4% of net merit derived from a selection index whose components were identical to those for net merit. We consider that the selection index comprising the first three lactation milk yields and persistency is a practical method for increasing lifetime milk yield in the absence of data regarding HL. Applying SNP to the second- and third-lactation traits and HL increased net merit and HL by maximizing the increased economic importance of later lactation traits, reducing the effect of first-lactation milk yield on HL (genetic correlation ($r_G$) = -0.006), and by augmenting the effects of the second- and third-lactation milk yields on HL ($r_G$ = 0.118 and 0.257, respectively).