• Journal of the Institute of Convergence Signal Processing
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• v.10 no.2
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• pp.120-126
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• 2009

There are many different types of surface defects on semiconductor Integrated Chips (IC's) caused by various factors during manufacturing process, such as cracks, foreign materials, chip-outs, chips, and voids. These defects must be detected and classified by an inspection system for productivity improvement and effective process control. Among defects, in particular, foreign materials and chips are the most difficult ones to classify accurately. A vision system composed of a carefully designed optical system and a processing algorithm is proposed to detect and classify the defects on QFN(Quad Flat No-leads) packages. The processing algorithm uses features derived from the defect's position and brightness value in the Maximum Likelihood classifier and the optical system is designed to effectively extract the features used in the classifier. In experiments we confirm that this method gives more effective result in classifying foreign materials and chips.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.381-381
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• 2010

$(ZrO_2)_{0.66}(HfO_2)_{0.34}$ thin films as gate dielectrics have been proposed to overcome the problems of tunneling current and degradation mobility inachieving a thin equivalent oxide thickness. An extremely thin $SiO_2$ layer is used in order to separate the carrier in MOSFET channel from the dielectric field fluctuation caused by phonons in the dielectric which decreases the carrier mobility. The electronic and optical properties influenced the device performance to a great extent. $(ZrO_2)_{0.66}(HfO_2)_{0.34}$ dielectric films on p-Si (100) were grown by atomic layer deposition method, for which the conduction band offsets, valence band offsets and band gapswere obtained by using X-ray photoelectron spectroscopy and reflection electron energy loss spectroscopy. The band gap, valence and conduction band offset values for $(ZrO_2)_{0.66}(HfO_2)_{0.34}$ dielectric thin film, grown on Si substrate were about 5.34, 2.35 and 1.87 eV respectively. This band alignment was similar to that of $ZrO_2$. In addition, The dielectric function (k, $\omega$), index of refraction n and the extinction coefficient k for the $(ZrO_2)_{0.66}(HfO_2)_{0.34}$ thin films were obtained from a quantitative analysis of REELS data by comparison to detailed dielectric response model calculations using the QUEELS-$\varepsilon$(k, $\omega$)-REELS software package. These optical properties are similar with $ZrO_2$ dielectric thin films.

• Parasites, Hosts and Diseases
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• v.29 no.1
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• pp.55-66
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• 1991

A numerical taxonomy was studied on a group of heterophyid trematodes and analysis was made on the following species: Metagonimus yokogawai (3 OTU, Operational Taxonomic Unit) , Metagcnimus Miyata Type (3 OTU), Metagonimus takahashii (2 OTU), Heterophyes dispar (2 OTU), Heterephyes heterophyes (1 OTU), Heterophyes nocens (2 OTV), Heterophyopsis continua (1 OTU), Pygidiopsis summa (3 OTU), Stellantchasmus falcatus (2 OTU) and Stictodora sari (2 OTU). Twenty-six morphological characters were measured and their values were expressed as relative ratios. Similarity and correlation matrix among each individuals were calculated. Clustering analysis by Ward's method and factor analysis were performed using the SAS (Statistical Analysis System) package. As a results, the groups belonging to the genus of Metegenimus were divided into three phonons (Awetegonimus yokogawai, Metegcnimus Miyata Type, M. takahashii) , and Metagonimus Miyata Type was classified as the level of subspecies of M. takahashii. The groups belonging to the genus Heterophyes were clearly divided into three phonons (Heterophyes dispar, H. heterephyes, H. nocens), and H. nccens was classified as not a subspecies level of H. heterophyes but a distinct species. Other species were classified as distinct phonons. From these results, the appllcr lion of numerical taxonomy on trematode classification is considered to be a great aid to determine the limit of taxa.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3301-3306
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• 2012

In LED chip packaging, die bonding is a very important process which fixes the LED chip on the lead frame to provide enough strength for the next process. Conventional pick-up device of the die bonder is simply operated by up and down motion of a collet and an ejector pin. However, this method may cause undesired problems such as position misalignment and/or severe die damage when the pick-up device reaches the die. In this study, to minimize the position alignment error and die damage, a die bonder is developed by adopting a new pick-up head for precise alignment and high speed feeding. To evaluate structural stability of the designed system, required finite element model of the die bonder is generated, and structural analysis is performed. Vibration analysis of the pick-up head is also performed using developed finite element model at operation frequency range. As a result of the analysis, deformation, stress, and natural frequency of the die bonder are investigated.

• Journal of Nutrition and Health
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• v.39 no.2
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• pp.133-144
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• 2006

The purpose of this study was to evaluate the nutritional status and to identify related factors in elderly hemodialysis patients. Sixty-four patients who were registered in Asan Medical Center, Seoul, Korea, participated in the study. The data was collected between September and December, 2003. General characteristics were obtained with the use of an interviewer-administered questionnaire. Anthropometric and biochemical data, 3-day dietary records and dietary habits were also obtained. The results of this study were analyzed with t-test or $X^2$-test using SPSS package program. The percentage of elderly hemodialysis patients who were undergoing mild to severe malnutrition (MN group) and were normal nutrition (NN group) by subjective global assessment (SGA) criteria were 46.9% and 53.1 %, respectively. Appetite (p < 0.05) and dietary cholesterol intakes (p < 0.05) were significantly lower in MN group than the NN group. Body mass index (BMI, p < 0.001), lean body mass (LBM, p < 0.05), triceps skinfold thickness (TSF, p < 0.01), mid ann circumference (MAC, p < 0.01) and mid ann muscle circumference (MAMC, p < 0.05) were also lower in the MN group than the NN group. There were also significant differences in blood urea nitrogen (BUN, p < 0.05), creatinine (p < 0.05), prealbumin (p < 0.001) and C-reactive protein (CRP, p < 0.05). SGA was negatively correlated with serum BUN, creatinine and pre albumin, dry weight, BMI, LBM, total body water, TSF, MAC and MAMC, and positively correlated with age. In stepwise multiple regression analysis, SGA was related to BMI, CRP, age and BUN. In conclusion, almost half of the subjects were in malnourished status and had lower values in anthropometric and biochemical data. Our results suggest that SGA is a simple and adequate method for assessing the nutritional status in elderly hemodialysis patients and adequate dietary guidelines based on individual nutritional status are needed in the patients.

• Geomechanics and Engineering
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• v.2 no.1
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• pp.1-18
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• 2010

The analysis of structure response and design of buried structures subjected to dynamic destructive loads have been receiving increasing interest due to recent severe damage caused by strong earthquakes and terrorist attacks. For a comprehensive design of buried structures subjected to blast loads to be conducted, the whole system behaviour including simulation of the explosion, propagation of shock waves through the soil medium, the interaction of the soil with the buried structure and the structure response needs to be simulated in a single model. Such a model will enable more realistic simulation of the fundamental physical behaviour. This paper presents a complete model simulating the whole system using the finite element package ABAQUS/Explicit. The Arbitrary Lagrange Euler Coupling formulation is used to model the explosive charge and the soil region near the explosion to eliminate the distortion of the mesh under high deformation, while the conventional finite element method is used to model the rest of the system. The elasto-plastic Drucker-Prager Cap model is used to model the soil behaviour. The explosion process is simulated using the Jones-Wilkens-Lee equation of state. The Concrete Damage Plasticity model is used to simulate the behaviour of concrete with the reinforcement considered as an elasto-plastic material. The contact interface between soil and structure is simulated using the general Mohr-Coulomb friction concept, which allows for sliding, separation and rebound between the buried structure surface and the surrounding soil. The behaviour of the whole system is evaluated using a numerical example which shows that the proposed model is capable of producing a realistic simulation of the physical system behaviour in a smooth numerical process.

• Journal of Technology Innovation
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• v.28 no.4
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• pp.63-93
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• 2020

We suggest a new way of specifying the co-evolution of product and process technologies, and integrating it into one of the well-received technology intelligence tools - a technology radar. Cross impact analysis enables us to identify the core technologies of product-process co-evolution. Combining expert judgment with its results, we can clarify the technological co-evolution trajectory with mainstream as well as emerging core technologies. Reflecting these in the assessment process of a technology radar, we could improve reliance of the technology assessment process and technology portfolio. From the academic perspective, our research provides a point where the co-evolution theory encouners technology intelligence methods. Practically, strategic capability of future-preparedness and strategic management could improve by adopting our method based on our example of co-evolution of semiconductor product and process technologies.

• Korean Journal of Applied Biomechanics
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• v.31 no.4
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• pp.283-289
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• 2021

Objective: The aim of this study was to analyze the pattern of Kolman technique by five Korean top gymnasts including the three national athletes on horizontal bar. Method: Two digital high-speed camcorders were used with 90 frames/sec and their Kolman motions were filmed in sports science secondary school gymnasium at U city. After the kinematic and kinetic variables were carried out by Kwon3D 3.1 motion package during the whole phase, the optimized release motion was investigated by simulating the body COG path during the aerial phase. Results: Firstly, it was revealed that the average changes of hip, shoulder joint angle were 84 deg, 53 deg respectively during the functional sub-phase and the average swing phaseal time was 1.21 s. Secondly, it was revealed that the average body COG positions and velocities (Y, Z) at release were -0.65 m, 0.48 m, 1.65 m/s, 3.97 m/s respectively and the average release angle, peak height and flight time were 67 deg, 1.29 m, 0.79 s respectively. Thirdly, it was revealed that the directions of somersault of whole and lower body, tilt of lower body were counterclockwise, whereas the directions of tilt of whole body, twist of whole and lower body were clockwise at the ready for re-grasp. Lastly, it was revealed that the body COG paths were different from each other during the aerial phase followed by the different body COG velocities. Conclusion: Korean gymnasts of this study controlled their motions well in terms of the timing of hip·shoulder joint, body position, body angular momentum especially during the functional sub-phase, but their motions were different during the aerial phase. Nonetheless most of them made the adequate body position at the instant of re-grasp. It would be suggested that Korean gymnasts except S3 should increase the vertical velocity.

• Journal of Convergence for Information Technology
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• v.11 no.10
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• pp.322-331
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• 2021

This study attempted to identify the multi-cultural acceptance level of freshmen in nursing colleges and to analyze the factors influencing it. For the research method, data were collected from 410 first-year nursing students at K University in W City through a questionnaire from March 1 to 28, 2021, and frequency, reliability analysis, t-test, ANOVA, correlation, and multiple regression were conducted using the open-source statistical package R. As a result of the study, the multi-cultural acceptance level of freshman in nursing colleges averaged 77.36 points, indicating that they have a slightly higher multi-cultural acceptance capacity, and as a result of analyzing the influence of multi-cultural acceptance related factors, Korean recognition requirements(𝛽=0.34, p<.001), perceived threat recognition for migrants (𝛽=0.29, p<.001), Experience in multi-cultural education(𝛽=0.14, p<.001), Recognition of the appropriate age for multi-cultural education (𝛽=0.20, p<.001) was statistically significant. According to results, it is necessary to develop and actively utilize regular curriculum and programs related to multi-culturalism for nursing students.

• Journal of Convergence for Information Technology
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• v.11 no.7
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• pp.253-263
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• 2021

This study aims to present effective teaching and learning methods for improving class satisfaction and improving the quality of university education by empirically analyzing changes in class satisfaction according to teaching methods such as face-to-face(FTF) classes, non-face-to-face(NFTF) classes, and blended classes of theories and practical subjects before and after COVID-19, targeting beauty major students who have a relatively higher proportion of practical classes than theoretical classes. For data analysis, SPSS 18.0 statistical package was used, and in the analysis of the difference in satisfaction with teaching methods for theoretical subjects before and after COVID-19, 10 items out of 20 items showed statistically significant differences, and 8 items out of 20 items in the practical subjects showed statistically significant differences. It is expected that the quality of university education will be improved by applying efficient and practical teaching methods considering the items affecting the class satisfaction according to the teaching and learning methods of these theories and practical subjects.