• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.192-196
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• 2005

Key part of main equipment in a gas turbine may be likely to be damaged due to operation under high temperature, high pressure, high-speed rotation, etc. Accordingly, the cost for maintenance increases and the damaged parts may cause generation to stop. The number of parts for maintenance also increases, but diagnostics technology fur the maintenance actually does not catch up with the demand. Blades are made of precipitation hardening Ni superalloy IN738 and the like for keeping hot strength. The surface of a blade is thermal-sprayed, using powder with main compositions such as Ni, Cr, Al, etc. in order to inhibit hot oxidation. Conventional regular maintenance of the coating layer of a blade is made by FPI (Fluorescent Penetrant Inspection) and MTP (Magnetic Particle Testing). Such methods, however, are complicated and take long time and also require much cost. In this study, defect diagnostics were tested for the coating layer of an industrial gas turbine blade, using an infraredthermography camera. Since the infrared thermography method can check a temperature distribution on a wide range of area by means of non-contact, it can advantageously save expenses and time as compared to conventional test methods. For the infrared thermography method, however, thermo-load must be applied onto a tested specimen and it is difficult to quantify the measured data. To solve the problems, this essay includes description about producing a specimen of a gas turbine blade (bucket), applying thermo-load onto the produced specimen, photographing thermography images by an infrared thermography camera, analyzing the thermography images, and pre-testing for analyzing defects on the coating layer of the gas turbine blade.

• Journal of Marine Bioscience and Biotechnology
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• v.3 no.1
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• pp.1-6
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• 2008

Angola has a coastline of about 1,650 km long. Two diverging current namely, the Angola current with its warm water from the north and the cold Benguella Current in the south create a strong up-welling with a high productive ecosystem for marine resources. The area from Lobito to the mouth of the Cunene River, also known as the Southern fishing zone is by far the most productive of Angola's fishing zones. In 1977, the total potential of its marine fisheries sector was estimated at more than 700,000 tonnes per annum. In 2003, the Total Allowable Catch (TAC) established for demersal species was 57,600 tonnes and 160,000 tonnes for pelagic species. The most important resources are various marine demersal and pelagic fish including pilchard and the Cape and Cunene horse Mackerel (Tranchurus capensis and T. trecae). Sardinellas (Sardinella aurita and S. maderensis) are fished in parallel with horse mackerel. The rest of the catches are mainly demersal spp. and some deep water crustaceans. The demersal sppecies consist of Hake (Merluccius polli and M. capensis) and the large eye dentex spp. Tunas are caught at certain times of the year whilst some marine shrimp are also harvested from the Angolan waters. Angola also has several high value freshwater fish species, exploited by about 255 fishers. Tilapia sp. is among the most important and abundant fresh water fish found in Angola. Other species include the catfish (Clarias gariepinus) and fresh water prawns (Macrobrachuin rosenbergii). Some aquaculture ponds have been established in the country side, but due to lack of investment, proper training and the impact of civil war have seriously limited developments in the sub sector.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.24 no.3
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• pp.131-140
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• 2018

As global environmental problems become more serious, bio plastic suppliers in developed countries are expected to drive demand for eco friendly packaging materials due to recycling regulations and consumer's attention. To catch up with this demand, various types of bio plastics have been introduced using plants such as corn and domestic companies are increasingly interested in this. Industrial interest in bio plastics is increasing to solve the recent environmental problems. The critical disadvantages of the weak mechanical strength and expensive product cost were gradually solved by extensive researches. In order to promote the active use of bio plastics, countries around the world are operation certification marks and standard systems. In this article, we have summarized recent trends in domestic and overseas bio plastics regulations, certification marks and identification labels.

• The Southeast Asian review
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• v.23 no.3
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• pp.135-179
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• 2013

This study explores the study experiences of Southeast Asian students at a reputable Korean private university in Seoul. In particular, this study focuses on difficulties and coping strategies of both non-native speaker of English and native-speakers of English who are working for their undergraduate or postgraduate degrees. Interviews of fourteen students from five Southeast Asian countries were collected and analyzed by NVivo 9. Thematic analysis result shows that many students, particularly non-native speakers of English, had much more difficulties than their counterparts, in contemporary Korean university context, where internationalization indices-driven strategies including expanding courses conducted in English language. Also, this study observes and documents contrasting patterns of different degree of difficulties experienced by students, depending on their degree levels and majors. Undergraduate students in science and engineering majors had the greatest degree of difficulties among all. In contrast, their graduate counterparts seem to have less difficulties. This might be related to the fact that graduate students in science and engineering majors are mostly working with their peers in their own labs, which provides institutional support. Coping strategies of students show that international students, facing unfavorable or unfriendly treatments by their Korean peers, developed innovative strategies, including using the internet technology to catch up with the classes that they could not fully understand. As a whole, adaptation process of international students do not seem to be passive or one-way. This study also provides policy implications for international students, particularly, who can be categorized as linguistic and ethnic minorities.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.24 no.4
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• pp.392-402
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• 2021

Purpose: The present study assessed the role of an amino acid-based formula (AAF) in the growth of infants with cow's milk protein allergy (CMPA). Methods: Non-breastfed, term infants aged 0-6 months with symptoms suggestive of CMPA were recruited from 10 pediatric centers in China. After enrollment, infants were started on AAF for two weeks, followed by an open food challenge (OFC) with cow's milk-based formula (CMF). Infants with confirmed CMPA remained on AAF until 9 months of age, in conjunction with a cow's milk protein-free complementary diet. Body weight, length, and head circumference were measured at enrollment and 9 months of age. Measurements were converted to weight-for-age, length-for-age, and head circumference-for-age Z scores (WAZ, LAZ, HCAZ), based on the World Health Organization growth reference. Results: Of 254 infants (median age 16.1 weeks, 50.9% male), 218 (85.8%) were diagnosed with non-IgE-mediated CMPA, 33 (13.0%) tolerated CMF, and 3 (1.2%) did not complete the OFC. The mean WAZ decreased from 0.119 to -0.029 between birth and enrollment (p=0.067), with significant catch-up growth to 0.178 at 9 months of age (p=0.012) while being fed the AAF. There were no significant changes in LAZ (0.400 vs. 0.552; p=0.214) or HCAZ (-0.356 vs. -0.284; p=0.705) from the time of enrollment to age 9 months, suggesting normal linear and head growth velocity. Conclusion: The amino acid-based study formula, in conjunction with a cow's milk proteinfree complementary diet, supported normal growth till 9 months of age in a cohort of Chinese infants with challenge-confirmed non-IgE-mediated CMPA.

• Journal of Navigation and Port Research
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• v.46 no.3
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• pp.243-250
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• 2022

The purpose of this study was to propose technology to detect the wave in the image in real-time, and calculate the height of the wave-overtopping through image analysis using artificial intelligence. It was confirmed that the proposed wave overtopping detection system proposed in this study could detect the occurring of wave overtopping, even in severe weather and at night in real-time. In particular, a filtering algorithm for determining if the wave overtopping event was used, to improve the accuracy of detecting the occurrence of wave overtopping, based on a convolutional neural networks to catch the wave overtopping in CCTV images in real-time. As a result, the accuracy of the wave overtopping detection through AP50 was reviewed as 59.6%, and the speed of the overtaking detection model was 70fps based on GPU, confirming that accuracy and speed are suitable for real-time wave overtopping detection.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.3
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• pp.365-378
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• 2022

Complete blood cell count(CBC) is a technique that counts leukocytes for each type of blood cell being analyzed. The principle is that laser is incident to ex vivo flowing leukocytes in a microcapillary tube and scattered light occurs by laser and leukocytes. By collecting the scattered light, we can count the types of cells because different cells generate different light-scattering patterns. However, the technique has an intrinsic limitation, scattering pattern is shown in a wide range region in the resulting, which makes it difficult to accurate analyze and use fluorescent dyes. To overcome this limitation, a new design of CBC with a dual laser, which irradiates with orthogonal angles for collecting quad-scattering information was proposed. Before development, the scattering difference depending on wavelength must be investigated to only catch up to the scattered signal by angles. Some studies, which focused on simple particles, have been conducted to theoretically and experimentally investigate different scatterings by wavelength. In this study, we propose an optical system for measuring scattered light and investigate a complex particle. As a result, the green laser made strong scattering signals in both the forward and side direction: 10% and 30%, respectively.

• International Journal of Advanced Culture Technology
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• v.11 no.1
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• pp.221-231
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• 2023

Nowadays, more and more countries are paying attention to basic teaching, so it can be found that they are carrying out a new round of basic teaching reform. The fundamental purpose is to adapt to the economic, cultural and technological development of the 21st century, so that their nationals will not be eliminated in the competition of the world environment, the spiritual civilization and material life of the nationals can be further improved, and they can have an advantage in the competition and catch up with the advanced level of the world. The cultivation of preschoolers' mental health determines the future development of a person. Through the long-term practice of art teaching at the Longyuan Branch of the District Third Kindergarten of Guangxi, This paper summarizes some effective teaching methods to cultivate children's connection ability and sense of security through aesthetic education.Firstly, preschoolers' contact ability was studied, and the aspects such as the definition of contact ability and the reasons for the formation of contact ability were explored. Secondly, the development of preschoolers' sense of security, what to avoid in order to develop a good sense of security and the effects of security on children were investigated. Finally, several specific teaching cases were written based on these theories. Through these cases, aesthetic education was utilized to promote preschoolers' contact ability and develop a sense of security. The study mainly draws the following conclusions that if children want to have a successful career, a happy family in the future, it is crucial to have the ability of connect and security in childhood. Aesthetic education can promote the formation of children's ability of connection and security.Finally, I write specific teaching cases based on the above theories and practice, through which these cases use aesthetic education to promote the formation of children's contact ability and sense of security.

• Journal of Technology Innovation
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• v.31 no.3
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• pp.1-37
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• 2023

The Korean innovation ecosystem has evolved from a catch up stage to a creative leader stage where government's role in creating a private sector driven, healthy and dynamic ecosystem is important. Korea's innovation ecosystem shows a stagnation of innovation performance and a lack of linkage activities within the national innovation ecosystem and in global cooperation, despite the dramatic advancement and expansion of the ecosystem. A next-generation innovation ecosystem model is required to create a future-oriented innovation ecosystem. The next generation innovation ecosystem was prepared on the basis of the framework, which has 6 elements among which inter-firm network is the the micro-foundation of the ecosystem. On the basis of the framework, assuming that the next generation innovation ecosystem is the evolved existing ecosystem, responsive the discontinuous change in market and technology, which is private sector driven healthy and dynamic ecosystem, the next generation innovation ecosystem model was created. The concrete details on the direction of the policy entities responsible for building the ecosystem was presented, and the contribution of this study was discussed.

• Clinical and Experimental Pediatrics
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• v.52 no.9
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• pp.984-990
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• 2009

Purpose : Being small for gestational age (SGA) is a risk factor of short stature in children. Genetic background such as mid-parental height (MPH) is known to influence growth of children born SGA. We studied the relationship between growth of children born SGA and MPH and studied the effects of insulin-like growth factor (IGF-I) and insulin-like growth factor binding protein 3 (IGFBP-3) on postnatal growth in children born SGA according to MPH. Methods : Forty-nine neonates born SGA were included in this study. We defined corrected height standard deviation score (cHtSDS) by modified height SDS (HtSDS) based on their MPH. We categorized subjects into group 1 consisting of children with cHtSDS ${\geq}0$ (n=35) and group 2 consisting of children with cHtSDS <0 (n=14), and compared IGF-I and IGFBP-3 between the two groups. Results : The HtSDSs and cHtSDSs in groups 1 and 2 were $0.06{\pm}1.05$ vs. $-0.95{\pm}0.85$ (P=0.000) and $0.78{\pm}0.93$ vs. $-0.46{\pm}0.67$ (P=0.000), respectively. IGF-I SDS was higher in group 1 than in group 2 ($2.82{\pm}3.69$ vs. $0.23{\pm}2.42$, P=0.012). Total cHtSDS ($0.42{\pm}1.03$) was significantly higher than HtSDS ($-0.22{\pm}1.10$) (P=0.000). Conclusion : Our results show that cHtSDS differs significantly from HtSDS. Growth assessment by standardized growth curve does not uniformly show effects of genetic factors. A more accurate assessment of growth uses a personalized corrected growth curve that considers the genetic factor measured by MPH.