• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.05a
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• pp.111-112
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• 2009

Diamond-like carbon (DLC) is a convenient term to indicate the compositions of the various forms of amorphous carbon (a-C), tetrahedral amorphous carbon (ta-C), hydrogenated amorphous carbon and tetrahedral amorphous carbon (a-C:H and ta-C:H). The a-C film with disordered graphitic ordering, such as soot, chars, glassy carbon, and evaporated a-C, is shown in the lower left hand corner. If the fraction of sp3 bonding reaches a high degree, such an a-C is denoted as tetrahedral amorphous carbon (ta-C), in order to distinguish it from sp2 a-C [2]. Two hydrocarbon polymers, that is, polyethylene (CH2)n and polyacetylene (CH)n, define the limits of the triangle in the right hand corner beyond which interconnecting C-C networks do not form, and only strait-chain molecules are formed. The DLC films, i.e. a-C, ta-C, a-C:H and ta-C:H, have some extreme properties similar to diamond, such as hardness, elastic modulus and chemical inertness. These films are great advantages for many applications. One of the most important applications of the carbon-based films is the coating for magnetic hard disk recording. The second successful application is wear protective and antireflective films for IR windows. The third application is wear protection of bearings and sliding friction parts. The fourth is precision gages for the automotive industry. Recently, exciting ongoing study [1] tries to deposit a carbon-based protective film on engine parts (e.g. engine cylinders and pistons) taking into account not only low friction and wear, but also self lubricating properties. Reduction of the oil consumption is expected. Currently, for an additional application field, the carbon-based films are extensively studied as excellent candidates for biocompatible films on biomedical implants. The carbon-based films consist of carbon, hydrogen and nitrogen, which are biologically harmless as well as the main elements of human body. Some in vitro and limited in vivo studies on the biological effects of carbon-based films have been studied [$2{\sim}5$].The carbon-based films have great potentials in many fields. However, a few technological issues for carbon-based film are still needed to be studied to improve the applicability. Aisenberg and Chabot [3] firstly prepared an amorphous carbon film on substrates remained at room temperature using a beam of carbon ions produced using argon plasma. Spencer et al. [4] had subsequently developed this field. Many deposition techniques for DLC films have been developed to increase the fraction of sp3 bonding in the films. The a-C films have been prepared by a variety of deposition methods such as ion plating, DC or RF sputtering, RF or DC plasma enhanced chemical vapor deposition (PECVD), electron cyclotron resonance chemical vapor deposition (ECR-CVD), ion implantation, ablation, pulsed laser deposition and cathodic arc deposition, from a variety of carbon target or gaseous sources materials [5]. Sputtering is the most common deposition method for a-C film. Deposited films by these plasma methods, such as plasma enhanced chemical vapor deposition (PECVD) [6], are ranged into the interior of the triangle. Application fields of DLC films investigated from papers. Many papers purposed to apply for tribology due to the carbon-based films of low friction and wear resistance. Figure 1 shows the percentage of DLC research interest for application field. The biggest portion is tribology field. It is occupied 57%. Second, biomedical field hold 14%. Nowadays, biomedical field is took notice in many countries and significantly increased the research papers. DLC films actually applied to many industries in 2005 as shown figure 2. The most applied fields are mold and machinery industries. It took over 50%. The automobile industry is more and more increase application parts. In the near future, automobile industry is expected a big market for DLC coating. Figure 1 Research interests of carbon-based filmsFigure 2 Demand ratio of DLC coating for industry in 2005. In this presentation, I will introduce a trend of carbon-based coating research and applications.

• The Journal of the Korea Contents Association
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• v.12 no.12
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• pp.223-236
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• 2012

This study's objective is to identify the factors that effect high school students' volunteer activities and suggest the political implications for the actual fulfillment of volunteer activities. We verified the relationships and effects on all factors based on the theory of planned behavior which is applied in explaining various human behavior. 220 high school student subjects for this study were randomly selected and filled out self-administered questionnaires. A total of 216 responses were used for analysis. Data analysis was done by obtaining reliability and validity after frequency analysis using SPSS 12.0 for Windows and AMOS 4.0 as well as evaluating the suitability of the study model. Regression analysis was carried out for hypothesis testing. The study results showed that firstly, all hypotheses based on the theory of planned behavior were supported re-confirming the usefulness of the theory in the field of various behavioral research for social welfare. Secondly, among all factors, perceived behavioral control showed to be the most influential in fulfilling active volunteer activities of high school students. Based on the results of our study, we proposed that research in the social welfare academia, practical endeavors in the educational field, and also political support system is necessary.

• Journal of the Korea Society of Computer and Information
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• v.16 no.10
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• pp.155-164
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• 2011

As Information & Communication Technology is developed in fast speed, the educational field undertakes many changes in utilizing Information Technology(IT). As the smart phone's educational utilization brings many positive effects, so many people are interested in such educational application programs. The e-textbooks or learning contents based on the web have shown some limits in being utilized as main learning materials in school field. So this study identified such limits, and suggested a new direction for professional education by integrating mobile and QR code technologies with existing textbooks to realize a new book-type E-Textbook model. And this study purposed for students to participate in their classes more easily through making open-education environment for students studying specialized subjects and by applying new teaching-learning methods inducing more interest in them. Of course, this study's ultimate purpose is to raise students' learning ability about specialized subjects, and further, to improve their self-directed learning abilities with increased interests in classes. As the result operating this model, it was found that this model had enough learning effect.

• Journal of Korea Soil Environment Society
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• v.1 no.2
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• pp.73-81
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• 1996

The self-diffusion coefficients of chloride and tritiated water ranged from 4.8 $\times$ 10-7 to 7.2 $\times$ 10-7 cm2/sec and 5.5 $\times$ 10-5 to 1.6 $\times$ 10-4 cm2/sec for three different depths of soil constituents at about 50% water content by volume, respectively Mobility of solute and water was conducted under steady-state flow conditions in a field soil consisting of 70 cm of clay to silty clay over a medium sand. A steady-state water flow conditions was maintained by applying irrigation water at a constant flux of 2cm per day. The water labeled with chloride and tritium was leached into the plot during the steady-state condition for 87 days. The positions of tritium and chloride as a function of soil depth and the time was measured by extracting samples of the soil solution with suction probes. Extremes in solute displacement occurred at equal and different depths within the plot. An analysis of these measurements indicated the observations of the pore-water velocity and the apparent diffusion coefficient were log normally disturbed. Twenty-four soil suction probes, used to identify the rate at which a solute was displaced in the soil, will yield an estimate of the mean pore-water velocity of this soils within a range of approximately 5% of its true value providing the effects of potential solute-soil interaction are taken into account.

• Proceedings of the Ginseng society Conference
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• 1998.06a
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• pp.1-11
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• 1998

Ameliorating mechanisms of red ginseng on learning deficits were investigated in the following 3 experiments; its effects on 1) place learning deficits in aged rats and in young rats with selective hippocampal lesions (behavioral study), 2) long-term potentiation in the hippocampal formation (neuro- physiological study), and 3) ChAT (choline acetyl transferase) activity in various brain regions of aged rats (pharmacological study). In the behavioral study, first, performance in the place learning tasks were compared among 3 groups of young and aged rats; control young intact rats (10-12 week old) treated with water, aged rats (28-32 month old) treated with water, and aged rats (28-32 month old) treated with red ginseng (100 mghglday) suspended in water. Second, performance in the place learning tasks was compared among 3 groups of young rats; control intact rats treated with water, rats with bilateral hippocampal lesions treated with water, and rats with bilateral hippocampal lesions treated with red ginseng (100 mg/kg/day). Each rat in these 2 behavioral experiments was tested with the 3 types of the place learning tasks in a circular open field using intracranial self-stimulation (ICSS) as reward. The ICSS reward was delivered if the rat (1) moved distance of 100-160 cm (DMT): (2) entered an experiment-determined reward place within the open field, and this place was randomly varied in sequential trials (RRPST); or (3) entered 2 specific places, and did a shuttle behavior between the 2 places (PLT). Performance of the aged rats in the ginseng group was not significantly different from that of control young rats in ICSS (current intensity, bar press rates), DMT and RRPST. However, treatment with red ginseng significantly ameliorated place-navigation learning deficits in aged rats in the PLT. Similarly, red ginseng ameliorated learning and memory deficits in young rats with hippocampal lesions in the same tasks. In the neurophysiological study using young rats, perfusion of hippocampal slices with non-sapon in fraction of red ginseng significantly enhanced magnitudes of the long-term potentiation (LfP) in the CA3 subfield. In the pharmacological study, treatment with red ginseng did not affect ChAT activity in aged rat brain including the hippocampal formation. These results strongly suggest that red ginseng ameliorates learning and memory deficits in aged rats through actions on the CA3 subfield of the hippocampal formation, which were independent of the presynaptic components of the cholinergic system

• Journal of Haehwa Medicine
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• v.12 no.1
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• pp.79-102
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• 2003

It has been believed that the human body can be effected by color, sound, smell, and taste - each of them is based on the original character. Out of these elements, the color can be a mediation that absorbs energy into human body and adapts it to the creatures whose life are definitely based on the solar energy. This thesis makes a study of the possibility of applying the color to the oriental medical science by researching the color psychology and therapy which are studied in the west medical science, the recognition and application of color developed from orientalism, and the opinion of color in the oriental medical science. Color therapy is one of the psychological treatment techniques that are able to recover and maintain the health with the rays of the sun rays and the color. The light and the color have its energy that may relax, harmonize, encourage, or excite a human being. This is because the wavelength and the vibration of each color will take effects to human body. The core energy of absorbing and distributing the color vibration is made in the 7 "chakras" in the body, which are the pith and marrow of bio-energy directly connected with the center of the nervous system. There are several methods in the color therapy - the treatment of solar ray, the color-bath, the water-therapy using color energy, the inducement of the solar energy into the body, the acupuncture, the therapy of crystal and jewel, and the self-suggestion dependent upon the color. The color therapy can help us to keep our balance by changing the emotion into the positive energy that will cure the disease with color. As a result, this method not only must be useful to cure physical disease, or develop into good health but also will be used in conforming itself to the mental disease. The color therapy mainly uses the eight colors, which are made by mixing Red, Yellow and Blue basic colors in the field. They are never used in the treatment, but they will go along with complementary colors. This rule is closely connected with the theory of yin and yang which lies at the root of oriental philosophy, and with the treatment principle of oriental medical science whose field is focused on the balancing the body mentally as well as physically. In the East, it is the Obangsaek - the color of blue, red, yellow, white, and black in the theory of yin and yang and the five elements that have been used in helping people having trouble with their health for a long time. In the view of the oriental medical science, these five colors attached the theory of five-elements have been very useful to the physiology, the pathology, or the diagnosis, and been applied to the medical treatment, combining themselves with a five-taste in medicinal herbs. Since the study of color and human physiology has been made in some different interest and fields these days, it goes to prove that the different function of color we couldn't have got before becomes very useful to the medical science. The color must be worth researching the diversity for applying itself to the oriental medical science.

• Geophysics and Geophysical Exploration
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• v.22 no.3
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• pp.107-115
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• 2019

Recently, since earthquakes have happened frequently in Gyeongju and Pohang areas in Korea, the earthquake detection research gets lots of attention. Geophysical monitoring data have been changed during the earthquake activity because the huge amount of energy is accumulated. The change of telluric current can be predicted by both of piezoelectric and electrokinetic effects before or during the earthquake occurrence, and if the change value exceeds the conventional telluric current noise, we can measure changes in the electric field associated with earthquakes. In this study, we have self-developed and verified the system that can monitor the telluric current. In order to verify our telluric current monitoring system, we installed lines of 40 m (E-W direction) and 28 m (N-S direction) on the site in Pohang. The telluric currents were sampled at 1 kHz for about a month. We have compared and analyzed the data of earthquake signals and electrical noises based on the earthquakes that occurred during the monitoring period. We have monitored if there were significant signals related to the earthquake on measured time series data. Through this study, we will suggest the direction of continuous research in the future.

• The Journal of the Convergence on Culture Technology
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• v.9 no.5
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• pp.685-695
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• 2023

This study aimed to investigate the current utilization and implications of digital learning support media in the field of French studies, and to explore future research directions. To achieve this, we conducted a comprehensive review of the use of digital media in various learning processes within French studies. Additionally, we examined the direct application of ChatGPT, an emerging technology, to learning by extending its use to foreign language and education fields. Our findings indicate that the application of digital learning support media in French studies is somewhat limited, with selective use in processes such as online class support media, pre-class learning, efficient learning and interaction, and self-directed learning. In the case of ChatGPT, our research found that no studies have been conducted within French studies, and very few studies have been conducted on its practical application in other educational fields. While ChatGPT has a wide range of applications and has shown positive effects on learners, ethical concerns have been raised regarding the quality, source, and reliability of information. Therefore, future research in French studies should focus on educational application and effectiveness verification in university teaching and learning situations, as well as interdisciplinary convergence with digital learning support media.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.3
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• pp.172-181
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• 2023

In order to raise the self-sufficiency rate of domestic forage and obtain informations necessary for production of high-quality winter forage, forage yield and feeding value were analyzed in the above-ground parts of a winter wheat 'Cheongwoo' harvested at five different growth stages, and the appropriate harvest time was determined. The yield increased until 30 days after heading, and then decreased afterwards. The proportion of spike in the above-ground part was less than 40% until 30 days after heading, but increased to more than 60% afterward. At 30 days after heading, the protein content and relative feed value (RFV) also reached peaks, while acid detergent fiber (ADF) and neutral detergent fiber (NDF) were low. The mineral nutrient contents are within the standard range required for feeding ruminant livestock or do not exceed the maximum allowable level. Therefore, the best time to harvest above-ground parts of a winter wheat 'Cheongwoo' for use as a forage for feeding ruminant livestock is around 30 days after heading, when considering forage yield and feed values. As a result it would match well in time with the transplantation of rice seedlings or the sowing of rice-alternative field crops in the double cropping system.

• Journal of the Korean Society of School Health
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• v.1 no.2
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• pp.86-117
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• 1988

The purpose of school lunch service programs (SLPs) is to provide school children with nutritious meals each day, to assist them in improving their mental and physical development, to make them understand the basic knowledge needed for healthy daily living throughout their lives with sound nutritional habits, and further, to enhance the national health status as well as the individual. The major purpose of this study is to describe the history and current status and promotional plans in Korea's SLSPs to improve the nation's health status. The major findings of this study are as follow: 1) The progression of the SLSPs can be devided into four major periods: Relief (1953-1972), Self-supportive (1973-1977), System-establishment (1973-1983), System-development(1984- ). 2) As result of the implementation of SLSPs in Korea, many positive effects have been found in school education, notably in the field of physical growth, social development and personality cultivation. 3) This study deals with a more detailed assessment with regard to the effects of the program on school education activities and the improvement of nutritional habits in the family. Although it is limited and not yet complete, the program implementation has contributed to the improvement in children's food-intake habits, understanding of food, and manners, and increased sanitary consciousness. It has also affected of parent's concerns and attitudes towards the improvement of daily meals as well as national eating patterns, and eventually provided motivation for increased farm production of nutritious food stuffs and reasonable food consumption. 4) The SLSPs does have its stare of problem such as an unsatisfactory budget, lack of understanding of the program by school personnel and parents. However, there is no doubt that the SLSPs should be carried out effectively for better health, and especially for the growth and development of the children. Finally, the problems and promotive Plans of the SLSPs can be approached by aspects of the administrative, financial and operational systems. These system have to coordinate with relevant authorities to expand participation in the program for the successful implementation of the SLSPs. The eventual objective this study is to propose ways and means for mobilizing every available element in the effort to attain the goals of educating and training healthy and competent personnel manpower, stabilizing the demand and supply of food and the ensuring adequate coordination of national food production and consumption.