• Journal of Powder Materials
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• v.26 no.4
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• pp.275-281
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• 2019

An artificial neural network (ANN) model is developed for the analysis and simulation of correlation between flake powder metallurgy parameters and properties of AA2024-SiC nanocomposites. The input parameters of the model are AA 2024 matrix size, ball milling time, and weight percentage of SiC nanoparticles and the output parameters are density and hardness. The model can predict the density and hardness of the unseen test data with a correlation of 0.986 beyond the experimental data. A user interface is designed to predict properties at new instances. We have used the model to simulate the individual as well as the combined influence of parameters on the properties. Moreover, we have analyzed the calculated results from the powder metallurgical point of view. The developed model can be used as a guide for further composite development.

• The Journal of Economics, Marketing and Management
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• v.12 no.1
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• pp.17-28
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• 2024

Purpose: This paper is designed to deliver a deeper understanding of the implications of digitalization strategies in the tourism industry, exploring the opportunities and challenges in South Korea. Research design, data and methodology: To identify effective strategies, an integrated approach is employed in the research that encompasses the Glocal RPM analysis and SANEL HERMES model, as well as the examination of digital tourism factors within the DIANA economy. The data used for this study were derived from multiple sources, including literature review, participation interview, tourist survey and expert questionnaire. By conducting a tourist survey using questionnaires in this research, Glocal RPM and SANEL HERMES hybrid method is used identifying and classifying influencing factors limiting digitalization in tourism. As a final step, experts use a Quantitative Strategic Planning Matrix to propose, assess, and rank a number of digitalization strategies. Results: According to the analysis, the study revealed that combining both tools contributes to a more holistic understanding of the environment, uncovering the positives and negatives from diverse perspectives. The average satisfaction percentage of experts was determined to be 38%, indicating anatal level of digitalization for tourism industry in South Korea. Conclusions: These results can serve as a valuable guide for policymakers and stakeholders in formulating targeted strategies to enhance glocalization, rationality, professionalism, and morality within the digitalization context.

• IEMEK Journal of Embedded Systems and Applications
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• v.18 no.5
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• pp.233-240
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• 2023

Nutrition information about food is written on the label paper, which is very inconvenient for visually impaired people to recognize. In order to solve the inconvenience of visually impaired people with nutritional information recognition, this paper proposes a product nutrition information guide system for visually impaired people. In the proposed system, user's image data input through UI, and object recognition is carried out through YOLO v5. The proposed system is a system that provides voice guidance on the names and nutrition information of recognized products. This paper constructs a new dataset that augments the 319 classes of canned/late-night snack product image data using rotate matrix techniques, pepper noise, and salt noise techniques. The proposed system compared and analyzed the performance of YOLO v5n, YOLO v5m, and YOLO v5l models through hyperparameter tuning and learned the dataset built with YOLO v5n models. This paper compares and analyzes the performance of the proposed system with that of previous studies.

• Analytical Science and Technology
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• v.33 no.6
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• pp.262-273
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• 2020

A fluorine content analysis method for krill oils, which is a representative oil formulation in foods, was developed in compliance with the Korea Food and Drug Ministry's "Guidelines for Validation of Testing Methods Related to Food". Using this method for krill oils, the presence of impurities was evaluated via combustion-ion chromatography (C-IC). A review of published technical data on fluorine in krill oils showed that while the traditional wet potentiometric method was typically used, it was not reliable. Moreover, there was no food testing/analysis laboratory in Korea to perform a fluorine test analysis on such an oil matrix. Therefore, we identified halogen (fluorine) tests, developed to national and international standards, and developed a test method suitable for krill oils by selecting a C-IC method that is sufficiently applicable to the oil matrix. Based on the characteristics of the oil matrix, the optimal test method was established through various experiments by reviewing the concerns related to loss and interference in the preparation and introduction of samples. The fluorine content test was carried out on 11 krill oil products that were purchased online. Most products (with the exception of only one) were found to contain less than the reporting limit obtained by the test method. Furthermore, after additional testing, a high fluorine content of approximately 2,000 ~ 3,000 mg/kg was detected on the krill surface, although the concentration varied depending on the area of the krill. A comparison with samples from two ISO/IEC 17025 testing laboratories confirmed that there was no significant difference in the statistical analysis results obtained by ANOVA among the three laboratories. A testing guide for fluorine content analysis was completed.

• Korean Journal of Environmental Agriculture
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• v.35 no.3
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• pp.223-233
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• 2016

BACKGROUND: This study was to develop a analytical reference material including twenty pesticides in tomato. To use it for proficiency test, the suitability of homogeneity, storage stability, assigned values and uncertainty for analytical reference material were important.METHODS AND RESULTS: In order to develop a analytical reference material of tomato for multi-residue analysis of pesticides, twenty-pesticides were treated in tomato and the samples were frozen and homogenized. The homogeneity, stability, assigned value and uncertainty were calculated according to the requirements of the KS A ISO Guide 35, KS Q ISO 13528 and EURL-PT protocol. The values of the within-bottle standard variation(s_wb) and the between-bottle standard variation(s_bb) were 0.9~6.5% of assigned value and the uncertainty(u*_bb) due to inhomogeneity was also calculated as 0.6~1.9% for all pesticides. This indicated that it was satisfactory to be used as a analytical reference material. The storage stabilities of twenty-pesticides at room temperature and freezing conditions were assessed according to the requirement of the KS Q ISO Guide 35. All pesticides were stable at room temperature (20~30℃) for 8 days and freezing (-20℃) for 23 days.CONCLUSION: The feasibility of analytical reference material for pesticide multi-residue analysis in a tomato matrix was investigated. Homogeneity of within/between-bottle, uncertainty and stabilities at room temperature and freezing condition were satisfactory for a use of proficiency test and quality control. From these results, a analytical reference material would be applicable to monitor the proficiency test of pesticide analysis organizations to improve the reliability and consistency.

• Analytical Science and Technology
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• v.21 no.5
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• pp.364-374
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• 2008

Antarctic Environmental Monitoring Handbook' was published by COMNAP/SCAR in 2000. The standardized method described in this handbook is recommended for monitoring of antarctic environment. High pressure bomb technique in this guide was used to decompose soil samples. In compliance with this guide book, high pressure bomb technique was applied to decompose the antarctic soil sampled at the King Sejong Station. An Isotope Dilution-Inductively Coupled Plasma-Mass Spectrometry (ID-ICP-MS) was applied to determine mass concentrations of Pb, Cu and Zn in the soil. The accuracy in this method was verified by the analysis of certified reference materials (CRM) of NIST 2702 (marine sediment). The analytical results agreed with certified value within the range from 99.5~100.8%. Matrix separation was necessitated for the determination of Cu and Zn by Chelex 100 ion exchange resin. As a result, the average mass concentrations of Pb, Cu and Zn which are suspected to be caused by anthropogenic pollution were 332.9 mg/kg, 95.6 mg/kg and 115.3 mg/kg, respectively. Those for the metals sampled in the soils of the remote regions from the station were 28.1 mg/kg, 101.8 mg/kg and 115.6 mg/kg, respectively.

• Korean Journal of Family Social Work
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• no.23
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• pp.263-302
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• 2008

The study had four purposes as follows; First, the researcher tried to find the characteristics of conflict. Second, the researcher attempted to find the factors influencing the conflict between mother and the eldest son, Third, the study attempted to find the therapist's intervention techniques, which were caused the change of the conflict between mother and the eldest son. Lastly, the study was to find the changed contents of family relationships. The total family counseling was 13 sessions, which included individual and family counseling. The study used constant comparative analysis by using open coding method to find the factors. Also, the researcher used Miles and Huberman's matrix and graphical network display to show the relationships among factors influencing the conflicts between mother and the eldest son. The study found the boundary problem of family, family's undifferentiated ego, dysfunctional communication patterns, and mother's experience from family of origin as factors influencing the conflict between mother and the eldest son. On the other hand, the study found that the therapist used the formation of therapeutic alliance relationship, guide of communication skills, the reflection of repeated pattern, reframing and a metaphor as intervention methods. The result of study revealed that changed level of family relationship, activating functional communication, changed boundary among family members, differentiated ego of family members, and changed cognition as the changed contents of family relationship.

• The Journal of Korean Society for School & Community Health Education
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• v.12 no.3
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• pp.1-15
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• 2011

Objectives: We describe the development of a smoking and drinking prevention program for adolescents, using intervention mapping. Methods: The study sample consisted of 1,000 high school second-grade students from 6 high schools in Seoul. The PRECEDE model was applied for the needs assessment. We carried out a social diagnosis by assessing the factors such as the quality of life, happiness level, and satisfaction with school life; an epidemiological diagnosis on the perceived health status, stress levels, and priority of health issues; a behavioral diagnosis on the smoking and drinking rate and the intention to smoke and drink; and an educational diagnosis on knowledge, beliefs, attitudes, self-efficacy, outcome expectations, social norms and life skills. Results: The development process included a needs assessment, identifying factors that influence smoking and drinking among adolescents. Intention, knowledge, perceived norms, perceived benefit, perceived cost, perceived susceptibility, self-efficacy, and life skills were identified as determinants. Three performance objectives were formulated to describe what an individual needs to do in order to avoid smoking and drinking. Subsequently, we constructed an intervention matrix by crossing the performance objectives with the selected determinants. Each cell describes the learning objectives of the smoking and drinking prevention program. The program used methods from the transtheoretical model, such as consciousness raising, outcome expectations, self-reevaluation, self-liberation, counterconditioning, environmental reevaluation, and stimulus control. The program deals with the effects of smoking and drinking, self-improvement, decision making, understanding advertisements, communication skills, social relationships, and assertiveness. Conclusions: By using the process of intervention mapping, the program developer was able to ensure a systematical incorporation of empirical and new data and theories to guide the intervention design. Programs targeting other health-related behavior and other methods or strategies can also be developed using this intervention mapping process.

• The Korean Journal of Malacology
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• v.26 no.1
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• pp.1-18
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• 2010

Biological organisms produce organic-inorganic nanocomposite composites that are hierarchically organized in composition and microstructure, containing both inorganic and organic components in complicated mixtures. The process related to the generation and regeneration of organic-inorganic complex in nature is called biomineralization process. Understanding how the process operates in a biological environment is a valuable guide to the synthesis of novel advanced material and developing important industrial processes. Like the mechanism of organisms, mollusks were also synthesized from interaction between organic matrices and minerals and their morphology was designed through biomineralization. In this study, shell formation has been studied as a bio-model and the application of biomimetics based on biomineralization is focused.

• Journal of KSNVE
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• v.6 no.2
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• pp.163-177
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• 1996

An investigation on thermohydraulic stability of flow oscillations in the CANada Deuterium Uranium-600(CANDU-6) heat transport system has been conducted. Flow oscillations in reactor coolant loops, comprising two heat sources and two heat sinks in series, are possibly caused by the response of the pressure to extraction of fluid in two-phase region. This response consists of two contributions, one arising from mass and another from enthalpy change in the two-phase region. The system computer code used in the investigation os SOPHT, which is capable of simulating steady states as well as transients with varying boundary conditions. The model was derived by linearizing and solving one-dimensional, homogeneous single- and two-phase flow conservation equations. The mass, energy and momentum equations with boundary conditions are set up throughout the system in matrix form based on a node-link structure. Loop stability was studied under full power conditions with interconnecting the two compressible two phase regions in the figure-of-eight circuit. The dominant function of the interconnecting pipe is the transfer of mass between the two-phase regions. Parametric survey of loop stability characteristics, i. e., damping ratio and period, has been made as a function of geometrical parameters of the interconnection line such as diameter, length, height and orifice flow coefficient. The stability characteristics with interconnection line has been clarified to provide a simple criterion to be used as a guide in scaling of the pipe.