• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.3
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• pp.82-88
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• 2014

The government expands its investment on R&D programs for economic growth, thus there is growing attention on the result of R&D Programs. This study proposes more improved measuring method for efficiency when the number of R&D programs is not enough to be for measuring efficiency analysis. It provides more various application method of factors on efficiency analysis. This study analyzes the influence of each input factor on efficiency by using partial efficiency concept. And it also determines input factors in similar influence throughout Spearman correlation coefficient. Finally, it suggests new method to improve discriminatory power of efficiency analysis by determining representative factors. Also, the proposed method can be practiced not only for national R&D programs, but also for other fields of research.

• Toxicological Research
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• v.20 no.4
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• pp.321-324
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• 2004

Lethal dose 50% ($LD_{50}$) has been commonly used as a parameter for the estimation of acute toxicity not only in animal experiment, but also in human study. Several methods to estimate $LD_{50}$ had been introduced, but Spearman-Karber and Berens-Karber method have been widely used due to their relative convenience and accuracy. However, $LD_{50}$ values estimated from the two methods showed inconsistency and variation depending on the characteristics of mortality data. In this study, the two methods were comparatively investigated in terms of accuracy and stability for the estimation of $LD_{50}$.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.7
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• pp.2957-2980
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• 2020

Ensemble clustering commonly integrates multiple basic partitions to obtain a more accurate clustering result than a single partition. Specifically, it exists an inevitable problem that the incomplete transformation from the original space to the integrated space. In this paper, a novel ensemble clustering algorithm using a newly reconstructed mapping coefficient (ECRMC) is proposed. In the algorithm, a newly reconstructed mapping coefficient between objects and micro-clusters is designed based on the principle of increasing information entropy to enhance effective information. This can reduce the information loss in the transformation from micro-clusters to the original space. Then the correlation of the micro-clusters is creatively calculated by the Spearman coefficient. Therefore, the revised co-association graph between objects can be built more accurately because the supplementary information can well ensure the completeness of the whole conversion process. Experiment results demonstrate that the ECRMC clustering algorithm has high performance, effectiveness, and feasibility.

• The Journal of Advanced Prosthodontics
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• v.6 no.1
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• pp.35-38
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• 2014

PURPOSE. This study aimed to evaluate the correlation between microleakage and screw loosening at different types of implant-abutment connections and/or geometries measuring the torque values before and after the leakage tests. MATERIALS AND METHODS. Three different abutment types (Intenal hex titanium, internal hex zirconium, morse tapered titanium) with different geometries were connected to its own implant fixture. All the abutments were tightened with a standard torque value then the composition was connected to the modified fluid filtration system. After the measurements of leakage removal torque values were re-measured. Kruskal-wallis test was performed for non-parametric and one-way ANOVA was performed for parametric data. The correlation was evaluated using Spearman Correlation Test (${\alpha}=0.05$). RESULTS. Significantly higher microleakage was found at the connection of implant-internal hex zirconium abutment. Observed mean torque value loss was also significantly higher than other connection geometries. Spearman tests revealed a significant correlation between microleakage and screw loosening. CONCLUSION. Microleakage may provoke screw loosening. Removing torque values rationally decrease with the increase of microleakage.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.12
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• pp.1199-1206
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• 2015

In this study, the exhaust gas of a diesel engine operating on biodiesel(BD) fuel(a mixture of diesel and soybean oil) was investigated for different fuel mixing ratios in the range of BD3 to BD100. The experiments were conducted using injection pressures of 400, 600, 800, 1000, and 1200 bar. The Pearson correlation coefficient and Spearman rank-order correlation coefficient were used to quantify the NOx and Soot emissions based on the fuel mixing ratio and injection pressure. Consequently, the Pearson correlation coefficient obtained for NOx and Soot emissions according to the mixing ratio and injection pressure was -0.811 and the corresponding Spearman rank-order correlation coefficient was -0.884, which indicated that the correlation of the NOx and Soot emissions was linear. Thus, the NOx and Soot have a trade-off relationship. Moreover, at each injection pressure, the Pearson correlation coefficient was a negative number, which indicated an inversely proportional relationship between NOx and Soot.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.1
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• pp.40-44
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• 2000

The purpose of study was to measure the interrater reliability of the newly developed caries diagnostic instrument, Diagnodent(KaVo, Germany), using a new laser fluorescence techinique. One hundred and three extracted human premolars and molars were examined by Diagnodent, three times for fissures and five times for smooth surfaces. There was no significant difference among the three fissure means, but two combinations showed significant differences among the five smooth surface means. Correlation coefficients of Pearson and Spearman were all above 0.9(P<0.01). The $\alpha$ values from reliability analysis were 0.9980 or 0.9981 for fissures and 0.9992 for smooth surfaces.

• Journal of KIISE
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• v.41 no.10
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• pp.799-809
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• 2014

In this paper, we address the problem of computing Pearson correlation coefficients and Spearman's rank correlation coefficients in a secure manner while data providers preserve privacy of their own data in distributed environment. For a data mining or data analysis in the distributed environment, data providers(data owners) need to share their original data with each other. However, the original data may often contain very sensitive information, and thus, data providers do not prefer to disclose their original data for preserving privacy. In this paper, we formally define the secure correlation computation, SCC in short, as the problem of computing correlation coefficients in the distributed computing environment while preserving the data privacy (i.e., not disclosing the sensitive data) of multiple data providers. We then present SCC solutions for Pearson and Spearman's correlation coefficients using secure scalar product. We show the correctness and secure property of the proposed solutions by presenting theorems and proving them formally. We also empirically show that the proposed solutions can be used for practical applications in the performance aspect.

• Journal of Korea Multimedia Society
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• v.13 no.10
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• pp.1444-1452
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• 2010

There is very little information on mobile terminal service systems such as CRUMPET because the all the users have different situations and characteristic, and so it is also difficult to find correlations. Because of the difficulty of customizing and recommending information based on preference stemming from the users' various situations and characteristics, they usually provide limited, conceptual information. This paper will recommend a system that recommends information tailored to the user's situation and characteristics, using the Spearman correlation coefficients. It finds correlations from users' information and sequences information that is suitable to the user's situation and characteristics into a list, thereby solving the problem of limited, conceptual information. Performance tests have revealed when compared to existing service systems, this system is more effective in terms of precision and recall, with a 92.3% precision rate, and a 73.8% recall rate.

• Journal of Convergence for Information Technology
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• v.10 no.11
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• pp.148-155
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• 2020

The purpose of the study was to test the reliability and validity of the Korean version of Pittsburgh Sleep Quality Index (PSQI-K) and to examine the cutoff point of the PSQI-K for screening insomnia among young adults. The subjective quality and patterns of sleep in 64 participants were measured using PSQI-K and Fitbit Charge 3^TM. The properties of the instrument were analyzed using Cronbach's alpha coefficient for the internal consistency reliability, factor analysis for the construct validity, and Spearman's rho correlation coefficient for the correlation between the PSQI-K total scores and Fitbit tracker scores. The Cronbach's alpha coefficient of the PSQI-K was 0.69. The Spearman's rho correlation coefficient between the PSQI-K and Fitbit tracker was higher than 0.67. A cutoff point of ≥6.0 had a sensitivity of 0.93 and a specificity of 0.84. In conclusion, the PSQI-K is a reliable and valid instrument to evaluate sleep disturbance in Korean young adults.

• Journal of Digital Convergence
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• v.11 no.11
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• pp.351-357
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• 2013

Information retrieval by query keywords have some mismatching problems to fit user's requirement for the retrieved documents due to the varieties of users. These problems are originated from the different situations and characteristics of user's requirement. Also, it has a problem that general correlation coefficients did not display the information relations. In this thesis, it is to suggest knowledge retrieval system to verify feasibility of personnel selection procedure and results supporting selection rules after construction of personnel selection ontologies and rules composed of various concept and knowledge based on the semantic web technology. In the suggested system, it is to clear disadvantages of limited information retrieval providing the suitable information to satisfy user's different situations and characteristics using Spearman's coefficients. Experimental results by this semantic-based information retrieval show 90.3% of accuracy and 71.8% of recall compared with legacy keyword information retrieval.