• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.4
• /
• pp.2828-2836
• /
• 2015

Evaluation items were deducted by based on literature materials to supplement the evaluation system of rock cut-slope in national road. Delphi survey of experts were conducted to review the final evaluation items. As a result of reviewing the significance through stepwise multiple linear regression, all of deducted items were statistically significant because these had lower P-value than 0.05. And It was confirmed that the items were selected appropriately as they had relatively similar levels of the weight. In consideration of CVR and reliability both suggested items and existing items, the exclusible items was selected and new items can complement existing evaluation system were added. Finally 18 rock cut-slope evaluation items was deducted.

• Journal of Korean Elementary Science Education
• /
• v.32 no.2
• /
• pp.139-158
• /
• 2013

This study investigated elementary students' (grade 4~6) learning progressions for water cycling drawn from iterative assessments using ordered multiple-choice (OMC) items. An assessment system, which consisted of construct map, item design, outcome space, and measurement model, was employed in this study to examine children's learning progressions. At the first stage of the assessment system, a construct map was designed on which children's conceptual understandings from naive to most sophisticated were represented. At the item design stage, 8 OMC items were drawn from the construct map. Each item option of the OMC items was scored from 0 to 3 according to its level of understanding at the stage of outcome space. As a measurement model, Rasch model, a branch of item response theory, was applied to interpreting the outcomes of the OMC items. This cycle of assessment system was furtherly implemented iteratively in order to elaborate on the first version of water cycling learning progression. In conclusion, children's understanding of water cycling could be described in two aspects: water distribution and water movement. We identified children's conjectural developmental pathways about water cycling existed from superficial and naive accounts to more complex and abstract accounts.

• Journal of Industrial Technology
• /
• v.22 no.A
• /
• pp.201-210
• /
• 2002

The object of this study is to evaluate the factors affecting the water quality and to propose the influence of dominant factor quantitatively. The correlation analysis was performed to know the correlationship among the water quality items As a result of partial correlation analysis, it was shown that the water quality items are affected by the rainfall item directly. The factor analysis was performed to grasp some number of factors on each point for deducing the items of similar variable characteristics. The four points were divided into different factor groups. It was grasped that $NH_3-N$ and $NO_3-N$ Items have different variable characteristics after comparing the items. The Multiple regression analysis can decrease the number of observation. In the deduced multiple regression formula, it was shown that the rate of T-N, $NH_3-N$ and $NO_3-N$ in the independent variable took about 60% among all the regression formulas.

• Journal of The Korean Association For Science Education
• /
• v.24 no.1
• /
• pp.17-28
• /
• 2004

The purpose of this study is to determine the patterns of differences between genders in science achievement. Eleventh grade, 140 female and male students were sampled from a school in Seoul. According to the analysis results of pilot study, 20 items were finally selected for the main study. To sharpen our interpretations of the factors and provide some confirmation, we supplemented the statistical analysis with a more detailed cognitive study of the items using think-aloud protocols and interviews with student test takers. The analysis of this study took into account the different item formats, contexts, and presentation styles. The findings are as follows: First, there was no significant gender difference between multiple-choice and open-ended items. Second, male students achieved significantly better in the context of everyday life in multiple-choice items. Third, male students favored items presented as written texts. Fourth, in problem-solving process, female students tend to apply their science concepts, whereas male students tend to apply their everyday experiences. The results of this investigation indicate that gender difference in science achievement depends heavily on item characteristics.

• Journal of The Korean Association For Science Education
• /
• v.24 no.6
• /
• pp.1143-1157
• /
• 2004

The purpose of this study was to develop HS-VOSTS(High School Students' Views On Science-Technology-Society), which is an instrument that monitors high school students' views on STS. For this study, 23 multiple-choice items were developed on four categories. First, a categorial scheme was constructed. The categorial scheme was based on many instruments that evaluate students' understanding on STS, literature review, and STS learning goal that many researchers had asserted. Second, the multiple-choice items were developed. The development of the items was carried out through four steps. In the first step, some pairs of statement on each subordinate category were formed. Next, the student statement questionaries which were based on the pairs of statement were responded by 772 students. In the second step, the response written by the students were analyzed to common viewpoints and the first multiple-choice items were constructed. In the third step, the semistructured interview with 28 high school students was implemented and the second multiple-choice items were constructed. In the fourth step, the final version of the instrument was developed through the analysis of the students' response on the second multiple-choice items. HS-VOSTS is an useful instrument for monitoring students' beliefs and viewpoints on STS topics. The results of the students' responses to HS-VOSTS items reflect the students' own thoughts directly. These results will give some implications for the curriculum developers, the authors of text books and the educational policy makers as well as the teachers.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.11 no.2
• /
• pp.63-72
• /
• 2011

Broadcast-based data dissemination has become a widely accepted approach of communication in the mobile computing environment. However, with a large set of data items, the expected delay of receiving a desired data increases due to the sequential nature of the broadcast channel. With the objective of minimizing this wait time, this paper explores the problem of data broadcast over multiple channels. In traditional approaches, data items are partitioned based on their access probabilities and allocated on multiple channels, assuming flat data scheduling per channel. If the data items allocated on the same channel are broadcast in different frequencies based on their access probabilities, the performance will be enhanced further. In this respect, this paper proposes a new broadcast scheduling scheme named two level dynamic programming(TLDP) which can reflect a variation of access probabilities among data items allocated on the same channel.

• Journal of Korean Academy of Nursing
• /
• v.33 no.6
• /
• pp.762-771
• /
• 2003

Purpose: This study was undertaken in order to determine factors affecting health promoting lifestyle of elderly women. Method: The subjects were 299 elderly community residing women over the age 65 living in 2 large cities. The instruments used for this study were a survey of general characteristics, health promoting lifestyle(47items), perceived health status(6 items), self-efficacy(l7 items), and social support(18 items). The data was analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation coefficients, and Stepwise Multiple Regression. Result: The result of the study are as follows: The average item score for the health promoting lifestyle was 2.46, the highest score on the subscale was interpersonal support(M=2.83). A significant difference between age, education level, income, experience of smoking, alcohol, exercise, and health promoting lifestyle were found. Stepwise multiple regression analysis revealed that the most powerful predictor of health promoting lifestyle was social support(55%). Conclusion: Social support accounted for 54% of the variance in health promoting lifestyle in the elderly women. Therefore, health promoting programs that increase social support should be developed to promote a healthy lifestyle of the elderly women.

• The Mathematical Education
• /
• v.48 no.4
• /
• pp.399-417
• /
• 2009

The purpose of this study was to explore the adaptability of U.S. multiple-choice items to measure Mathematical Knowledge for Teaching (MKT) in Korea. For this purpose, the authors selected the number and operations form B which was developed by Learning Mathematics for Teaching (LMT) project at the University of Michigan and then adapted items in terms of general cultural context, school cultural context, mathematical substances, and language in Korea. The survey was administrated to 77 Korean in-service teachers who had more than three years of teaching experiences. Based on the survey, the authors compared the data to that of U.S. teachers who had participated California's Mathematics Professional Development Institute. As a result, the survey measures less knowledge Korean teachers than more knowledgable Korean teachers and there are strong correlations of relative item difficulties between Korean teachers and U.S. teachers for both Content Knowledge (CK) items and Knowledge of Content and Students (KCS) items. This study implies the future direction for developing items to measure teacher knowledge as well as designing effective teacher education programs.

• Industrial Engineering and Management Systems
• /
• v.12 no.3
• /
• pp.172-180
• /
• 2013

We herein consider a stochastic multi-item inventory management problem in which a warehouse sells multiple items with stochastic demand and periodic replenishment from a supplier. Inventory management requires the timing and amounts of orders to be determined. For inventory replenishment, trucks of finite capacity are available. Most inventory management models consider either a single item or assume that multiple items are ordered independently, and whether there is sufficient space in trucks. The order cost is commonly calculated based on the number of carriers and the usage fees of carriers. In this situation, we can reduce future shipments by supplementing items to an order, even if the item is not scheduled to be ordered. On the other hand, we can reduce the average number of items in storage by reducing the order volume and at the risk of running out of stock. The primary variables of interest in the present research are the average number of items in storage, the stock-out volume, and the number of carriers used. We formulate this problem as a multi-objective optimization problem. In a numerical experiment based on actual shipment data, we consider the item shipping characteristics and simulate the warehouse replenishing items coordinately. The results of the simulation indicate that applying a conventional ordering policy individually will not provide effective inventory management.

• Journal of the Korean Geotechnical Society
• /
• v.29 no.11
• /
• pp.99-106
• /
• 2013

In this study, the correlation of evaluation items and safety rating for 104 of large-scale slopes along the general national road was analyzed. And, we proposed the regression model to predict the safety rating using the multiple regressions analysis. As the result, it is shown that the evaluation items of slope angle, rainfall and groundwater have a low correlation with safety rating. Also, the regression model suggested by multiple regression analysis shows high predictive value, and it would be possible to apply if the evaluation items of excavation condition and groundwater (rainfall) are not clear.