• Journal of Radiation Industry
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• v.17 no.4
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• pp.345-357
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• 2023

Nuclear forensics has been understood as a mendatory component in the international society for nuclear material control and non-proliferation verification. Radiochronometry of nuclear activities for nuclear forensics are decay series characteristics of nuclear materials and the Bateman equation to estimate when nuclear materials were purified and produced. Radiochronometry values have uncertainty of measurement due to the uncertainty factors in the estimation process. These uncertainties should be calculated using appropriate evaluation methods that are representative of the accuracy and reliability. The IAEA, US, and EU have been researched on radiochronometry and uncertainty of measurement, although the uncertainty calculation method using the Bateman equation is limited by the underestimation of the decay constant and the impossibility of estimating the age of more than one generation, so it is necessary to conduct uncertainty calculation research using computer simulation such as Monte Carlo method. This highlights the need for research using computational simulations, such as the Monte Carlo method, to overcome these limitations. In this study, we have analyzed mathematical models and the LHS (Latin Hypercube Sampling) methods to enhance the reliability of radiochronometry which is to develop an uncertainty algorithm for nuclear material radiochronometry using Bateman Equation. We analyzed the LHS method, which can obtain effective statistical results with a small number of samples, and applied it to algorithms that are Monte Carlo methods for uncertainty calculation by computer simulation. This was implemented through the MATLAB computational software. The uncertainty calculation model using mathematical models demonstrated characteristics based on the relationship between sensitivity coefficients and radiative equilibrium. Computational simulation random sampling showed characteristics dependent on random sampling methods, sampling iteration counts, and the probability distribution of uncertainty factors. For validation, we compared models from various international organizations, mathematical models, and the Monte Carlo method. The developed algorithm was found to perform calculations at an equivalent level of accuracy compared to overseas institutions and mathematical model-based methods. To enhance usability, future research and comparisons·validations need to incorporate more complex decay chains and non-homogeneous conditions. The results of this study can serve as foundational technology in the nuclear forensics field, providing tools for the identification of signature nuclides and aiding in the research, development, comparison, and validation of related technologies.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.21 no.3
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• pp.150-165
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• 2008

Objective : An adequate measurement for Atopic Dermatitis(AD) is essential for studies about the treatment of AD. To establish a new and adequate scoring system for AD in Korean medicine, we reviewed existing studies on AD outcome measurement in Korean medicine. Method : We searched for reviews on measurements of AD or studies which used an AD outcome measurement at the Korean Traditional Knowledge Portal from 1995 to June, 2008. And then we reviewed the pattern identification in AD patients and the outcome measurements for AD in each study. Results : 1. Among 25 studies, the most common measurement for AD was SCORAD(the severity SCORing of Atopic Dermatitis index), there were 16 studies. There was one study which used the Jakob T scoring system, one study which used ADSI(the Atopic Dermatitis Severity Index), and there were 7 studies which established or used a new severity scoring system for AD. 2. In Korean medicine, AD caused by Damp-Heat is accompanied by erythema, papulation, oozing and crust, Damp-Heat accompanied by Spleen-Gi deficiency is frequently found in pediatric patients, and in adults who have indigestion. Symptoms of AD caused by blood deficiency and Wind-Dryness include lichenification, dryness, scale and pigmentation. AD caused by toxic Heat in the blood system has symptoms similar to some Damp-Heat pattern along with symptoms of blood deficiency and Wind-Dryness. Conclusion : We need to establish a new severity scoring system which reflects pattern identifications and treatments with Korean medicine, and we should assess the validity, reliability, and sensitivity of the new scoring system.

• Journal of the Korean Magnetics Society
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• v.12 no.5
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• pp.168-173
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• 2002

Electrostatic discharge characteristics were studied by connecting human body model (HBM) with tunneling magnetoresistance (TMR) device in this research. TMR samples were converted into electrical equivalent circuit with HBM and it was simulated utilizing PSPICE. Discharge characteristics were observed by changing the component values of the junction model in this equivalent circuit. The results show that resistance and capacitance of the TMR junction were determinative components that dominate the sensitivity of the electrostatic discharge(ESD). Reducing the resistance oi the junction area and lead line is more profitable to increase the recording density rather than increasing the capacitance to improve the endurance for ESD events. Endurance at DC state was performed by checking breakdown and failure voltages for applied DC voltage. HBM voltage that a TMR device could endure was estimated when the DC failure voltage was regarded as the HBM failure voltage.

• Korean Journal of Human Ecology
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• v.21 no.3
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• pp.505-526
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• 2012

The purpose of this research is to investigate changes in ethical consumption practices after taking an undergraduate course 'Consumption and Ethics'. Through Qualitative & Quantitative research methods, students' pre-course and post-course attitudes were compared to understand changes in behavior. Before taking the course 'Consumption and Ethics', undergraduate participants displayed little regard for ethical consumption, instead displaying primary sensitivity to price and values based on self-centered and conspicuous consumption. After taking the course 'Consumption and Ethics', participants displayed a more altruistic awareness of consumption on society and the environment. In addition, participants displayed a stronger sense of pride as ethical consumer. These emerging values were contrasted with conflicting feelings resulting from the higher prices often associated with ethical products, feelings of regret resulting from ethically-based impulse purchases, and an inability to categorically evaluate the reliability of available information on the ethical products. However, participants demonstrated a willingness to practice ethical consumption and recommend ethical consumption to their friends and neighbors. Overall, participants in the study demonstrated a strong shift to be an ethical consumer as a result of taking the course 'Consumption and Ethics'.

• Journal of Environmental Science International
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• v.26 no.11
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• pp.1255-1266
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• 2017

Phosphorus (P) is an essential and major nutrient for both plants and animals. However, anthropogenic P in the environment may cause severe problems such as the deterioration of water quality. Therefore, it is essential for the Korean government to manage P in the agricultural sector. The annual P budget for Korea was 46 kg P ha-1 in 2013, placing Korea in second among Organisation for Economic Co-operation and Development (OECD) countries. P surplus and deficiency in agricultural lands can be estimated according to the P budget, which is one of the OECD agri-environment indicators. In the P budget, it is important to ensure consistency in the input-output data sources, in order to apply national and regional policies for the environmentally sound management of agricultural P. This study examines the impacts on the input-output data sources in the regional P budget in Korea. P budgets were between 99-145 kg-P/ha, depending on different data sources. We suggest two recommended data combinations (DC 1 and DC 2) for reliability of the data. P budgets calculated using DC 1 and DC 2 were 128 kg-P/ha and 97 kg-P/ha, respectively. According to the results, one of the core factors affecting P budgets was crop production. In this study, DC 2 was recommended rather than DC 1 in order to consider the cultivated areas for various crops. It is also necessary to analyze the sensitivity of the coefficients used in P budget in the future.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.361.1-361.1
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• 2016

Due to their high sensitivity, fast response, small energy consumption and ease of integration, nanoelectromechanical systems (NEMS) have attracted much interest in various applications such as high speed memory devices, energy harvesting devices, frequency tunable RF receivers, and ultra sensitive mass sensors. Since the device performance of NEMS is closely related with the mechanical and flexural properties of the material in NEMS, analysis of the mechanical and flexural properties such as intrinsic tensile stress and Young's modulus is a crucial factor for designing the NEMS structures. In the present work, the intrinsic mechanical properties of highly stressed silicon nitride (SiN) beams are investigated as a function of the beam length using two different techniques: (i) dynamic flexural measurement using optical interferometry and (ii) quasi-static flexural measurement using atomic force microscopy. The reliability of the results is analysed by comparing the results from the two different measurement techniques. In addition, the mass density, Young's modulus and internal stress of the SiN beams are estimated by combining the techniques, and the prospect of SiN based NEMS for application in high sensitive mass sensors is discussed.

• Advances in aircraft and spacecraft science
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• v.5 no.4
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• pp.499-513
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• 2018

One of the major problems in glass fiber reinforced epoxy (GFRE) composite pipes is the durability under water absorption. This condition is generally recognized to cause degradations in strength and mechanical properties. Therefore, there is a need for an intelligent system for detecting the absorption rate and computing the mass of water absorption (M%) as a function of absorption time (t). The present work represents a new non-destructive evaluation (NDE) technique for detecting the water absorption rate by evaluating the dielectric properties of glass fiber and epoxy resin composite pipes subjected to internal hydrostatic pressure at room temperature. The variation in the dielectric signatures is employed to design an electrical capacitance sensor (ECS) with high sensitivity to detect such defects. ECS consists of twelve electrodes mounted on the outer surface of the pipe. Radius-electrode ratio is defined as the ratio of inner and outer radius of pipe. A finite element (FE) simulation model is developed to measure the capacitance values and node potential distribution of ECS electrodes on the basis of water absorption rate in the pipe material as a function of absorption time. The arrangements for positioning12-electrode sensor parameters such as capacitance, capacitance change and change rate of capacitance are analyzed by ANSYS and MATLAB to plot the mass of water absorption curve against absorption time (t). An analytical model based on a Fickian diffusion model is conducted to predict the saturation level of water absorption ($M_S$) from the obtained mass of water absorption curve. The FE results are in excellent agreement with the analytical results and experimental results available in the literature, thus, validating the accuracy and reliability of the proposed expert system.

• The Korean Journal of Cytopathology
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• v.7 no.2
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• pp.111-121
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• 1996

Fine needle aspiration cytology(FNAC) is preferred because of simplicity, safety, and reliability in the evaluation of patients with thyroid nodule or hyperplasia. However, there are a few limitations such as false-negative or false-positive cases and non-diagnostic material. To evaluate the usefulness of FNAC in thyroid lesions, we reviewed 704 FNAC cases of thyroid nodules from 1988 to 1994 at Soonchunhyang University Hospital. The results are as follows. 1. Among 704 FNAC cases of thyroid gland, 571(81.1%) cases were benign, 12(1.7%) were suspicious, 71(10.1%) were malignancy, and 50(7.1%) were material insufficiency. The cytologic diagnoses of the benign lesions included 168 cases of follicular neoplasm, 139 cases of adenomatous goiter, 162 cases of follicular lesion such as follicular neoplasm or adenomatous goiter, 61 cases of Hashimoto's thyroiditis, 13 cases of subacute thyroiditis, and 28 cases of colloidal nodule or benign nodule. The malignant lesions included 68 cases of papillary carcinona, two medullary carcinomas and a case of metastatic colon cancer. 2. The average number of cytologic smear slides was $4.12{\pm}1.81$ in material insufficiency and $5.63{\pm}1.79$ in diagnostic cases. This difference was statistically significant(p<0.00001). 3. Histological assessment of 150 cases revealed 2 false negative and 1 false positive cases. The false negative cases were a case of marked sclerosis in papillary carcinoma and an occult case of papillary carcinoma. The false positive case resulted from pseudo-ground glass nuclei due to marked dry artifact. 4. Comparison between the FNAC and the histologic diagnosis revealed that FNAC had a sensitivity of 93.5%, a specificity of 99.2%, a false negative rate of 6.6%, a false positive rate of 0.8%, and an overall diagnostic accuracy of 98.0%. Therefore, FNAC of thyroid gland is a very reliable diagnostic method with excellent accuracy rate.

• The Journal of Pediatrics of Korean Medicine
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• v.26 no.1
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• pp.60-69
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• 2012

Background Children's Eating Behaviour Questionnaire (CEBQ) is a parents-targeted questionnaire to measure eating behavior of children, developed in United Kingdom and verified validity and reliability in several countries. Validity of Korean version of CEBQ (K-CEBQ) was verified in 2009. Objectives The study was conducted to assess the appetite improvement after herbal treatment in children who have anorexia. Methods The parents of the 26 children(anorexia 11, non-anorexia 15; $79.54{\pm}38.17$ months) who visited one university hospital was surveyed using K-CEBQ from April 2010 to April 2011. It was re-surveyed at intervals of 3 months. Differences between the anorexia group and the non-anorexia group were analyzed by Mann-Whitney U test, and comparisons of pre-treatment and post-treatment in anorexia group and non-anorexia group were verified by Wilcoxon signed-rank test. Results Depends on the presence of anorexia in child, Slowness in eating/Satiety responsiveness (SE/SR), Enjoyment of food (EF), Emotional undereating (EUE) and total scores were significantly different ($p$<0.05). Also, there were significant difference in SE/SR and total scores before and after the herbal treatment in anorexia group (p<0.05), and all scores tended to increase a few. However there were no significant difference before and after the herbal treatment in non-anorexia group, and the scores except for Desire to drink (DD) and Emotional overeating (EOE) were decreased. Conclusions Herbal treatment in children who have anorexia has improved their appetite in terms of eating sensitivity.

• Journal of the Korean Society for Nondestructive Testing
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• v.18 no.4
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• pp.304-312
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• 1998

In order to assure the reliability and integrity of structures such as bridges, Power and petrochemical plants, nondestructive evaluation techniques are recently playing more important roles. Among the various kinds of nondestructive evaluation techniques, ultrasonic technique is one of the most widely used methods for nondestructive inspection of internal defects in structures. For the reliable quantitative evaluation of internal defects from the experimental ultrasonic signals, a numerical analysis of ultrasonic scattering field due to a defect distribution is absolutely required. In this paper, the SH-wave scattering by multi-cavity defects using elastodynamic boundary element method is studied. The effects of shape of defects on transmitted and reflected fields are considered. The interaction of multi-cavity defects in 50-wave scattering is also investigated. Numerical calculation by the boundary element method has been carried out to predict near field solution of scattered fields of ultrasonic SH-wave. The presented results would be useful to improve the sensitivity of flaw defection for inverse analysis and pursue quantitative nondestructive evaluation for inverse problem.