• Journal of Korean Society on Water Environment
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• v.16 no.4
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• pp.431-443
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• 2000

Water quality data from water treatment plants in Korea during 1994-1998 were investigated to find out the characteristics of their non compliance. The number of plants surveyed were approximately 600 and the number of samples were over 30,000. Ten parameters of water quality selected in this study and their non compliance % (inside parenthesis) were as follows: Heterotrophic plate count (0.14%), Total coliforms (0.08%), $NH_3$-N (0.29%), $NO_3$-N (0.14%), THMs (0.02%), Turbidity (0.11%), Residual chlorine (5.5%), $KMnO_4$ consumption (0.04%), Hardness (0.03%), pH (0.07%). These levels of non compliance were compared to those obtained from WIDB (Water Industry Database, 1996) of American Water Works Association. This study strongly supported that small water plants (<10,000 tons/day) were more vulnerable in meeting the regulation criteria of many water quality parameters such as Heterotrophic plate count. Total coliforms, $NO_3$-N, THMs, Turbidity, Residual chlorine, $KMnO_1$ consumption, Hardness and pH. The $NH_3$-N concentration was especially high in winter and its violation was frequently found in the specific areas such as the downstream of major rivers. The average THMs concentration was surprisingly low, indicating $13{\mu}g/L$ which is 43% of US. Accordingly, these characteristics must be reflected in establishing the effective management of water quality policy of drinking water in Korea.

• Journal of the Korean Data and Information Science Society
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• v.28 no.5
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• pp.1145-1152
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• 2017

Environmental tests are used to verify an equipment that can withstand the rigors of harsh environments. In general, military products have lots of experiences with extreme environment compared to commercial products. Therefore, the military products used in mountains require a tailoring process about temperature drop for the environmental test. The International Organization for Standardization publishes that the coefficient of temperature drop is $-6.5^{\circ}C/1000m$ from all around the world. However, there is no the criteria in the South Korea. In this paper, we calculate the coefficient of temperature drop. Also, an equation used as a tailoring process for a low temperature test of the products has been suggested.

• Journal of Korean Society of Water and Wastewater
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• v.35 no.3
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• pp.187-196
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• 2021

When evaluating the extent of the impact of water pollutants on the surrounding area, we would like to present the target level (proposal) of the quality of the environment, which is the standard for evaluation. We propose the environmental quality target level for substances that need to be applied domestically by investigating overseas cases operating the integrated environmental management system and the implications of domestic environmental pollutant management. The appropriateness of the environmental quality target level reviewed in this study was determined using data from the water quality measuring network, and future improvement measures were proposed. We review the available methodologies for setting quality objectives for the environment. It proposed the environmental quality target level for 21 substances that have domestic water pollutant emission standards and do not have environmental standards, and proposed future improvement measures. If it is necessary to add quality target-level items of the environment in the future, it is believed that expansion will be possible based on the methodology presented in this study.

• Journal of Korean Society for Quality Management
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• v.46 no.1
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• pp.27-38
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• 2018

Purpose: A large number of attributes with mixed levels are often considered in the conjoint analysis. In the cases where attributes have two or three levels, we research on the efficient design of survey questionnaire to estimate all the main effect and two factor interaction effects with a reasonable size of it. Methods: To reduce the number of questions in a questionnaire, the balanced incomplete block mixed level factorial design with minimum aberration was proposed by Lim and Chung (2016). Based on the number of questions and that of the respondents in that design, D-optimality criterion is adopted to find efficient designs where the main effect and two factor interaction effects are estimated. Results: The list of the number of questions and that of the respondents in efficient designs for survey questionnaire are recommended based on the D-efficiency of each design and the proposed selection criteria for the number of both questions and the respondents. By analyzing all the respondents survey data generated by the simulation study, we find the proper model. Conclusion: The proposed methods of designing survey questionnaires seem to perform well in the sense that how often the proper model is found in a simulation study where all the respondents survey data are generated by the simulation model.

• Journal of Korean Society for Quality Management
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• v.42 no.1
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• pp.81-89
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• 2014

Purpose: The purpose of this study is to propose Clinical Practice Guideline(CPG) model and Clinical Index(CI) for implementing CDSS in digital hospitals. Methods: This study uses EMR data at department of family practice in A hospital; 636 patients, 570 diseases (based on ICD 10-CM criteria), and 37,000 data related with labs and treatments. This study focuses on disease J342 which is the most high rate of incidence. Results: Using the suggested model, this study calculates frequency matrix and probability matrix to find out the correlation of diseases and labs. This study indicates the lab sets of Disease (J342) as CI for CPG. Conclusion: This study suggests CPG model including Lab-based, Disease-Based and Case-based modules. Through 6 level cased-based CPG model, especially, this study develops Clinical Index(CI) such as the Incidence Rate, Lab Rate, Disease Lab Rate, Disease confirmed by Lab.

• Journal of Korean Society for Quality Management
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• v.47 no.3
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• pp.631-639
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• 2019

Purpose: In this paper we present a case study of applying quick and easy experimental design approach to develop a Halogen free flame retardant material for cellular phone charger cable. Methods: We employ sequential experimentation of mixture design, verification design, and factorial design. A quick and easy approach is adopted based on data investigation and graphical method instead of strict statistical analysis, which helped enhancing smooth communication with the engineers and speeding up the development process. Results: Flame retardant material in pellet type produced from the optimal condition is transported to the customer and tested, to pass the customer retardancy criteria. Conclusion: The quick and easy experimental design approach is considered to be useful in this case study.

• International Journal of Computer Science & Network Security
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• v.23 no.5
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• pp.163-171
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• 2023

The intelligent transportation system has made a huge leap in the level of human services, which has had a positive impact on the quality of life of users. On the other hand, these services are becoming a new source of risk due to the use of data collected from vehicles, on which intelligent systems rely to create automatic contextual adaptation. Most of the popular privacy protection methods, such as Dummy and obfuscation, cannot be used with many services because of their impact on the accuracy of the service provided itself, they depend on changing the number of vehicles or their physical locations. This research presents a new approach based on the shuffling Nicknames of vehicles. It fully maintains the quality of the service and prevents tracking users permanently, penetrating their privacy, revealing their whereabouts, or discovering additional details about the nature of their behavior and movements. Our approach is based on creating a central Nicknames Pool in the cloud as well as distributed subpools in fog nodes to avoid intelligent delays and overloading of the central architecture. Finally, we will prove by simulation and discussion by examples the superiority of the proposed approach and its ability to adapt to new services and provide an effective level of protection. In the comparison, we will rely on the wellknown privacy criteria: Entropy, Ubiquity, and Performance.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.6_1
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• pp.575-583
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• 2007

Surface segmentation aims to represent the terrain as a set of bounded and analytically defined surface patches. Many previous segmentation methods have been developed to extract planar patches from LIDAR data for building extraction. However, most of them were not fully satisfactory for more general applications in terms of the degree of automation and the quality of the segmentation results. This is mainly caused from the limited information derived from LIDAR data. The purpose of this study is thus to develop an automatic method to perform surface segmentation by combining not only LIDAR data but also images. A region-based method is proposed to generate a set of planar patches by grouping LIDAR points. The grouping criteria are based on both the coordinates of the points and the corresponding intensity values computed from the images. This method has been applied to urban data and the segmentation results are compared with the reference data acquired by manual segmentation. 76% of the test area is correctly segmented. Under-segmentation is rarely founded but over-segmentation still exists. If the over-segmentation is mitigated by merging adjacent patches with similar properties as a post-process, the proposed segmentation method can be effectively utilized for a reliable intermediate process toward automatic extraction of 3D model of the real world.

• Transactions of Materials Processing
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• v.31 no.4
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• pp.229-239
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• 2022

Convolution Neural Network(CNN) is a class of deep learning algorithms and can be used for image analysis. In particular, it has excellent performance in finding the pattern of images. Therefore, CNN is commonly applied for recognizing, learning and classifying images. In this study, the surface defect classification performance of Al 6061 extruded material using CNN-based algorithms were compared and evaluated. First, the data collection criteria were suggested and a total of 2,024 datasets were prepared. And they were randomly classified into 1,417 learning data and 607 evaluation data. After that, the size and quality of the training data set were improved using data augmentation techniques to increase the performance of deep learning. The CNN-based algorithms used in this study were VGGNet-16, VGGNet-19, ResNet-50 and DenseNet-121. The evaluation of the defect classification performance was made by comparing the accuracy, loss, and learning speed using verification data. The DenseNet-121 algorithm showed better performance than other algorithms with an accuracy of 99.13% and a loss value of 0.037. This was due to the structural characteristics of the DenseNet model, and the information loss was reduced by acquiring information from all previous layers for image identification in this algorithm. Based on the above results, the possibility of machine vision application of CNN-based model for the surface defect classification of Al extruded materials was also discussed.

• Journal of Korean Academy of Nursing Administration
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• v.2 no.1
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• pp.57-72
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• 1996

Provision of better nursing care to patients is a difficult but important task. The first problem for nursing quality improvement is development of evaluation tool for the quality of nursing care. This study tries to develop a patient care tool for patients with chronic renal failure. This study as a procedural evaluation of patient care, tries to show what, how, at what order to provide care to patients with chronic renal failure. This study is divided into process of development of tool, its reliability and validity. Among process of development of tool is focal group, small expert group and expert evaluation group. To develop approprieteness of tool, nurses working is four major hospitals is Seoul were selected. To evaluate the credibility of subjects, 19 patient who were hospitalized and discharged within 3 months were selected. The period for collecting data for reliability and valiability evaluation was between Sept. 20 to Oct. 18, 1995. The development process of this study is as follows ; 1. Make preliminary list of the tool by focal group consisting of 8 clinical nurses. 2. Modify and add preliminary list by 4 expert nursing panel. 3. Calculate content validity of the tool by 23 nursing expert panel of judge. 4. Verity relability and validity of the tool. 5. Finalize an evaluation tool for the quality of nursing care in chronic renal failure patient. The result of this study were as follows ; 1. Development of evaluation tool for the quality of nursing care in chronic renal failure. 1) The evaluation of this study was developed 5 standards, 28 criteria. and 130 indicators 2) Nursing care evaluation scores for chronic renal failure patients were average 68.8. 2. Verity reliability and validity of the tool. 1) 5 standards were divided into 4 point scale and according to 28 creteria, indicators of standard were 3.72 and of criteria were 3.77 2) Inter - rater reliability (consentaneity score) of the tool by pearson correlation coefficient betwwen rates were r= .72, r= .75 and interreliabilities by single - facet crossed design were r= .96. 3) The alpha coeffecient relating to internal consistency was .7259 over 27 items of 28 criterias of developed tool. Through this study, I'm sure that the developed tool for the quality of patient care in chronic-renal failure patient will show the way of more improvement of the quality of nursing care and effective nursing intervention.