• Journal of the Korean GEO-environmental Society
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• v.2 no.4
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• pp.73-81
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• 2001

Soil cement has been the typical material for the pavement and soft ground improvement. It has not been used up to date because that quality control is not easy and durability is not long enough for practical application. Since environmental influence is important, the application of high strength soil cement pavement has been increased for pedestrian roads of the garden, golf courses and sidewalks recently. In this study, the reference table was suggested for mixing design with appling statistical experimental technique to reference table. The reference table showed the relationship among improved strength, Soilcrete stabilizer, fine sand ratio and superplasticizer agent. The objective soil used in this study was the soft marine clay that is widely found in Korea, the compressive strength range of improved soil was between $50{\sim}150kg/cm^2$.

• Journal of the Korea Safety Management & Science
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• v.20 no.1
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• pp.41-55
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• 2018

For several decades, attribute classification methods using the asymmetrical relationship between an attribute performance and the satisfaction of that attribute have been explored by numerous researchers. In particular, the Kano model, which classifies quality attributes into 5 elements using simple questionnaire and two-dimensional evaluation table, has gained popularity: Attractive, One-dimensional, Must-be, Indifferent, and Reverse quality. As Kano's model is well accepted, many literatures have introduced categorization methods using the Kano's evaluation table at attribute level. However, they applied different terminologies and classification criteria and this causes confusion and misunderstanding. Therefore, a criterion for quality classification at attribute level is necessary. This study is aimed to suggest a new attribute classification method that sub-categorizes quality attributes using 5-point ordinal point and Kano's two-dimensional evaluation table through an extensive literature review. For this, the current study examines the intrinsic and extrinsic problems of the well-recognized Kano model that have been used for measuring customer satisfaction of products and services. For empirical study, the author conducted a comparative study between the results of Kano's model and the proposed method for an e-learning case (33 attributes). Results show that the proposed method is better in terms of ease of use and understanding of kano's results and this result will contribute to the further development of the attractive quality theory that enables to understand both the customers explicit and implicit needs.

• Industry Promotion Research
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• v.8 no.2
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• pp.149-156
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• 2023

The purpose of this study is to investigate and analyze the effects of sports fun factors on the willingness to continue exercising and psychological happiness of table tennis club members. The participants in this study collected data using a questionnaire about sports fun factors, willingness to continue exercising, and psychological happiness of 293 table tennis club members. The factors influencing the willingness to continue exercising were identified as victory/competition, interpersonal relationships, practice/benefit, and family support, and the will to continue exercising was found to have a significant static influence on both self-realization and hedonic pleasure. As a result of the mediating effect analysis of the will to continue exercise, the mediating effects of fun factors such as competence/awareness, victory/competition, interpersonal relationships, practice/benefits, and family support, on psychological happiness, self-realization and hedonic pleasure are confirmed as mediating effect except for competence/perception. In particular, it was confirmed that the interpersonal relationship (team atmosphere) factor had a higher mediating effect on self-realization and hedonic pleasure than other factors.

• Journal of the Optical Society of Korea
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• v.17 no.2
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• pp.219-223
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• 2013

The purpose of this study was to determine the relationship between the spherical equivalent visual acuity (VA) and uncorrected astigmatism. On 108 emmetropic eyes, the spherical equivalent VA was measured for cross cylindrical lens (CC lens)-induced astigmatic eyes and the VA-astigmatism relation determined. On 158 astigmatic eyes, the spherical equivalent VA and corrected astigmatism were measured and the measured values were compared with the calculated values from the VA-astigmatism relation by correlation coefficient analysis. Subsequent to that, the relationship between spherical equivalent VA and uncorrected astigmatism was made. The relationship was fitted for an exponential equation. Correlation coefficient between calculated values by equation and measured values for astigmatic eyes was 0.991 (p<0.01). The relationship between the spherical equivalent VA and the uncorrected astigmatism was decided as follows (spherical equivalent VA / uncorrected astigmatism): 1.0 / 0.25 D, 0.9 / 0.50 D, 0.8 / 0.75 D, 0.7 / 1.00 D, 0.6 / 1.25 D, 0.5 / 1.50 D, 0.4 / 2.00 D, 0.3 / 2.50 D, 0.2 / 3.00 D, 0.1 / 4.00 D, and 0.05 / 4.75 D. In conclusion, the relationship table devised from this study is a useful reference for predicting uncorrected astigmatism by measurement of decimal VA in spherical equivalent.

• Advances in concrete construction
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• v.13 no.3
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• pp.215-221
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• 2022

Considering their similar mass densities, an attempt was made to optimize the mix design of micro-concrete that used barite sand as an aggregate by substituting marble powder (5%, 10%, 20%, 30%, 40%, 50%, 70%), clay brick powder (30%, 50%, 70%), and fly ash (30%, 50%, 70%) for the concrete (by mass) to form specimens for shaking table tests. The test results showed that for these three groups of materials, the substitutions had little effect on the density. The barite sand played a decisive role in the density, and the overall density of the specimens reached approximately 2.9 g/cm³. The compressive strength and elastic modulus decreased with an increase in the substitution rates for the three types of materials. Among them, the 28 day compressive strength values of the 40% and 50% marble powder groups were 11.73 MPa and 8.33 MPa, respectively, which were 58.7% and 70.7% lower than the control group, respectively. Their elastic modulus values were 1.33×10⁴ MPa and 1.42×10⁴ MPa, respectively, which were 39.1% and 35% lower than those of the control group, respectively. The 28 day compressive strength values of the 50% and 70% clay brick powder groups were 13.13 MPa and 5.8 MPa, respectively, which were 53.8% and 79.6% lower than the control group, respectively. Their elastic modulus values were 1.54×10⁴ MPa and 1.19×10⁴ MPa, respectively, which were 29.7% and 45.4% lower than those of the control group, respectively. The 28 day compressive strength values of the 50% and 70% fly ash groups were 13.5 MPa and 7.1 MPa, respectively, which were 52.5% and 75% lower than those of the control group, respectively. Their elastic modulus values were 1.36×10⁴ MPa and 0.95×10⁴ MPa, respectively, which were 37.9% and 56.6% lower than those of the control group, respectively. There was a linear relationship between the 28 day compressive strength and elastic modulus, with the correlation coefficient reaching a value higher than 0.88. The test results showed that the model materials met the high density, low compressive strength, and low elastic modulus requirements for shaking table tests, and the test data of the three groups of different alternative materials were compared and analyzed to provide references and assistance for relevant model testers.

• Journal of Internet Computing and Services
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• v.8 no.4
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• pp.105-117
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• 2007

In order to succeed in a bid or development, the project manager should estimate its cost and schedule more accurately in the early stage of the project. Usually, the nominal schedule of most projects can be derived from rule of thumb, first-order estimation practice, or ball-park schedule estimation table. But the rule-of-thumb models for the nominal schedule estimation are so various, and the first-order estimation practice does not provide sufficient information. So they do not help much to decide on the proper development effort and schedule for a particular size of project. This paper presents a statistical regression model for deciding the development effort and schedule of a project using the ball-park schedule estimation table. First, we have redefined such words suggested in the ballpark schedule estimation table as shortest possible schedule, efficient schedule and nominal schedule, Next, we have investigated the relationship between the development effort and the schedule. Finally, we have suggested a model for estimating the development effort and the more accurate schedule of such particular sizes of software as are not presented in the ball-park schedule estimation table. The experimental results show that our proposed regression analysis model decreases the mean magnitude of relative error by 2% at maximum. Also this model can estimated the development effort and schedule for a particular size of software.

• Communications for Statistical Applications and Methods
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• v.10 no.2
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• pp.291-303
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• 2003

This work is proposed an alternative identification method of outlying cell which is one of important issues in categorical data analysis. One finds that there is a strong relationship between the location of an outlying cell and the corresponding parameter estimates of the well-fitted log-linear model. Among parameters of log-linear model, an outlying cell is affected by interaction terms rather than main effect terms. Hence one could identify an outlying cell by investigating of parameter estimates in an appropriate log-linear model.

• Journal of the Speleological Society of Korea
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• no.78
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• pp.33-41
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• 2007

Alpine caves, subterranean passages, are extensively controlled by folds and faults. Caves of the regions demonstrate a significant dip of the passages due to the structural deformations. There are many vertical voids and shaft. Speleo-scapes in the internal caves are various. Calcite formations show the water table alternations which indicate the uplifting and erosional base level droppings during at least the Quaternary. Around cave entrenches there are remnants of the Fluvial terraces on the middle of the hills. These relationship between cave locations and terraces will generate a key to the Plestocene history of the south Korean peninsula. Hence, the Korean karst is turned as "the overburden alpine karst".

• East Asian mathematical journal
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• v.38 no.1
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• pp.107-127
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• 2022

In this paper, we discuss the relationship between doubly-pointed Heegaard diagrams of (1, 1)-knots in lens spaces and Dunwoody 3-manifolds, and then give explicit representations of n-fold cyclic branched coverings of all (1, 1)-knots in S³ up to 10 crossings in Rolfsen's knot table as Dunwoody 3-manifolds.

• The Korean Journal of Elementary Counseling
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• v.6 no.1
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• pp.193-215
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• 2007

The purpose of this study was to identify the effect of the Peer Relationship Program on the school adjustment of Ha-nul with the school maladjustment by peer problems. To achieve this purpose, single subject pretest-pottiest design was implemented for Ha-nul with school maladjustment in the third grade of the elementary school. As for the testing period of this study, this program was carried out one time a week for 10 weeks from Sept 11, 2006 to Oct 13, 2006. Each test lasted for $40{\sim}60$ minutes. To find out changes in the school adjustment of the subject child, the progress in change before and after tests was comparatively analyzed through a Likert-type three-step evaluation scale and presented as tables and graphs regarding the target behavior table. And the school adjustability was calculated in terms of percentage and presented as tables and bar graphs through a Likert-type four-step evaluation scale. Change in the subject Ha-nul's behavior, which was shown in test scenes, was observed and recorded and then Qualitatively analyzed. The following conclusions were drawn from the results of this study: First, the Peer relationship improvement program was effective in the positive influence to the relationship between a teacher in charge and Ha-nul with the school maladjustment This program made a confidence and increased the ability to express one's own ideas and feelings to others. Second, the Peer relationship improvement program was effective in the positive influence to the relationship between schoolfellows and Ha-nul with the school maladjustment This program provided the opportunities to get along with peers naturally and the abilities of a mutual understanding. Third, the Peer relationship improvement program was effective in the partially positive influence to Ha-nul with the school maladjustment. Fourth, the Peer relationship improvement program was effective in the positive influence to follow the school rules by experiencing a role, concession and fairness through the various activities. Fifth, the Peer relationship improvement program was effective in the positive influence to take part in the school event with a self-confidence and cooperation with peers through the various activities.