• The KIPS Transactions:PartB
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• v.9B no.2
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• pp.139-146
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• 2002

The robot soccer simulation game is a dynamic multi-agent environment. In this paper we suggest a new reinforcement learning approach to each agent's dynamic positioning in such dynamic environment. Reinforcement learning is the machine learning in which an agent learns from indirect, delayed reward an optimal policy to choose sequences of actions that produce the greatest cumulative reward. Therefore the reinforcement learning is different from supervised learning in the sense that there is no presentation of input-output pairs as training examples. Furthermore, model-free reinforcement learning algorithms like Q-learning do not require defining or learning any models of the surrounding environment. Nevertheless these algorithms can learn the optimal policy if the agent can visit every state-action pair infinitely. However, the biggest problem of monolithic reinforcement learning is that its straightforward applications do not successfully scale up to more complex environments due to the intractable large space of states. In order to address this problem, we suggest Adaptive Mediation-based Modular Q-Learning (AMMQL) as an improvement of the existing Modular Q-Learning (MQL). While simple modular Q-learning combines the results from each learning module in a fixed way, AMMQL combines them in a more flexible way by assigning different weight to each module according to its contribution to rewards. Therefore in addition to resolving the problem of large state space effectively, AMMQL can show higher adaptability to environmental changes than pure MQL. In this paper we use the AMMQL algorithn as a learning method for dynamic positioning of the robot soccer agent, and implement a robot soccer agent system called Cogitoniks.

• Journal of the Korean Magnetics Society
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• v.17 no.1
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• pp.43-46
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• 2007

The samples were synthesized by using a solid state reaction. The X-ray diffraction pattern for $Ti_{0.96}Co_{0.02}Fe_{0.02}O_2$ showed a pure rutile phase with tetragonal structures. Mixtures of the proper proportions of the elements sealed in evacuated quartz ampoule were heated at $870{\sim}930^{\circ}C$ for one day and then slowly cooled down to room temperature at a rate of $10^{\circ}C/h$. In order to obtain single phase material, it was necessary to grind the sample after the first firing and to press the powders into pellets before annealing them for a second time in evacuated and sealed quartz ampoule. Magnetic properties have been investigated using the vibrating sample magnetometer(VSM). Room temperature magnetic hysteresis(M-H) curve showed an obvious ferromagnetic behavior and the magnetic moment per Fe atom under the applied of 0.8T was estimated to be about $1.3{\mu}_B/CoFe$. But the magnetic moment per Fe atom under the applied of 0.8T was estimated to be about $0.02{\mu}_B/CoFe$ without Ti-getter.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.7
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• pp.1448-1452
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• 2004

In this paper, a photodiode capable of obtaining a sufficient photo/ dark current ratio at both a forward bias state and a reverse bias state is proposed. The photodiode includes a glass substrate, an Cr thin film formed as a lower electrode over the glass substrate, Cr silicide thin film(∼l00$\AA$) ) formed as a schottky barrier over the Cr thin film, a hydrogenated amorphous silicon film formed as a photo conduction layer over a portion of the Cr silicide thin film. Transparent conduction film ITO (thickness 100nm) formed as an upper electrode over the hydro-generated amorphous silicon film is then deposited in pure argon at room temperature for the Schottky contact and light window. The high quality Cr silicide thin film using annealing of Cr and a-Si:H is formed and analyzed by experiment. We have obtained the film with a superior characteristics. The dark current of the ITO/a-Si:H Schottky at a reverse bias of -5V is ∼3$\times$IO-12 A/un2, and one of the lowest reported, hitherto. AES(Auger Electron Spectroscophy) measurements indicate that this notable improvement in device characteristics stems from reduced diffusion of oxygen, rather than indium, from the ITO into the a-Si:H layer, thus, preserving the integrity of the Schottky interface. The spectral response of the photodiode for wavelengths in the range from 400nm to 800nm shows the expected behavior whereby the photocurrent is governed by the absorption characteristics of a-Si:H.

• Korean journal of communication and information
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• v.22
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• pp.77-106
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• 2003

As globalization of communication is going on and as the media have become increasingly central to the world economy, media policy matters have become the province of world economic organizations like the IMF and the WTO. The WTO service negotiation is focused primarily on the discriminatory and quantitative barriers associated with the trade of audiovisual services. Domestic measures such as subsidization, content regulation including quotas, and licensing requirements and restrictions on foreign ownership and control are at issues here. These measures have been successfully implemented by countries wishing to withstand competition from the American audiovisual industry. The debate about trade in audiovisual services is permeated by the unstated assumption that these programs are pure commodities whose production, distribution, exhibition and in turn, values are solely determined by the market forces. It is therefore presumed that liberalization of trade in audiovisual services will benefit all, serving cultural pluralism and diversity as well as economic efficiency. However, this assumption is not shared by developing countries, the recipients of U.S. television material. They argue audiovisual sector requires a social and cultural approach, since it plays a key role in the preservation of people's identity and social bonds. They claim that it is the each state's right to define its media policy and to implement it through the means it considers fit. These clashing views over the nature of the audiovisual material and the ways in which protect cultural pluralism and diversity do not confine to be the realm of theoretical debate. Each state's interest and motivation to protect its local industry and to have a competitive advantage in the international market is working in this battle. Consolidation with the countries like Australia, Canada, and EU nations, in favour of cultural exemption, seems to be the best policy for us. However, we are not entirely free from the WTO pressures, considering relation to the U. S. This study analyzes Korean Broadcasting Law compared with those of other OECD countries and tries to propose some strategical guidelines facing WTO service negotiation in the area of broadcasting.

• Journal of Ginseng Research
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• v.3 no.1
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• pp.1-34
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• 1979

Our nation is confronted with the situation that the rice, a principal food, short of some essential amino acids, leads to imbalanced meals insufficient in the nutrient of Protein, to bring many difficulties in the elevation of nutritional state in our nation. While. our country has been produced much amounts of Panax Ginseng roots which has a stimulating effects on the metabolism of protein, lipid and nucleic acids in the body. And the leaf and trunk of Panax Ginseng were also produced a considerable amounts as the by-products. Author believe that these by-products (leaf and trunk) of Panax Ginseng might have some components possessing simillar activity with Panax Ginseng root although the quantity and qualify of the functional components may more or less be different. Therefore, this study was demised to observe the supplemental effect of the Panax Ginseng-by-Products on the dietary protein efficiency and nutritional state of rats. The feeds used for this experiment were rice containing 30% barely, fish four, and the leaf, trunk and small root of the Panax Ginseng, and the contents of the general nutrients including protein, lipid and carbohydrate etc. in each feed were analyzed for the combination of each feed. And, being based on analytical values of Protein in food. fish Pour as Protein source was added were rice containing 30% barely to be include 8.6 to 8.7%, 12%, 15% and 18% of protein. Then 2% of the leaf, trunk or small reef of Panax Ginseng was supplemented into each of above protein diet group, ton 16 kinds of diets were Prepared. The male albino rats from a Pure strain, weighing 70g to 80g. were used for experimental animals. They were maintained with coresponding fist for f and 8 weeks, and the growth rate, consumption of diets and protein, efficiency of feed and Protein in animals were determined. The lipids, proteins and cholesterols in serum and liver were also determined quantitatively after they were sacrificed in coresponding term. The results obtained are summarized as follows: 1. Body weigh of diet group containing 8.6 to 8.7%,12%, and 15% of protein are increased remarkably by supplement of 2% of the leaf or small root of Panax Ginseng in comparison with each of controls. But this tendency could not observed in diet group containing 18eA Proteins. 2. Feed efficiency showed same tendency in comparison with changes of gained body weight. Specially, in each of diets containing 8.7%, 12%, 15% and 18% of Proteins, supplement of the leaf of Panax Ginseng showed the better feed efficiency than supplement of the trunk or small root. 3. In feeding group for 8 weeks, protein efficiency showed worst efficiency in diet containing 18% proteins and showed the best efficiency was the diet group containing 12% Proteins. And the efficiency was improved according to supplement of the leaf of Panax Ginseng. 4. Nitrogen contents in serum and liver did not show large differences each other in all diet groups. But contexts of total cholesterol and 1ipid were decreased markedly in diet groups containing 12%, 15% and 18% of proteins in comparison with diet group containing 8.6% to 8.8% of proteins.

• Korean Journal of Mineralogy and Petrology
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• v.36 no.1
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• pp.1-17
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• 2023

On painting cultural properties to which Orpiment, a traditional yellow mineral pigment, is applied, the color's degeneration is frequently observed. To identify the cause of the degeneration, this study takes a look into orpiment and the various pigments that are mixed into it (Lead White, Lead Red, and Cinnabar) in powder and painting state. The pigment was mixed with Argyo glue and then applied to korean traditional paper and silk. Considering the possibility that alum causes the discoloration, it was applied to the specimen. With a UV tester, the powders and the painted specimens were subjected to a light resistance test in three phases (96 hour). Color changes were measured with a colorimeter and minerals, chemical composition and structural changes were analysed by XRD, SEM/EDS and Raman spectrometers. While the color change of pure Orpiment powder according to the light resistance test was small, the colored specimen became darker. The color change was large in the Orpiment colored on the silk and in the alum-treated specimen. In Orpiment powder was produced white arsenolite as altered orpiment after UV test. In the mixed powder of Orpiment and Lead White were detected only the constituent minerals of Orpiment and Lead White, and no altered substances were produced. Whereas after the UV test, orpiment and arsenolite, which were altered substances of orpiment, and the constituent minerals of Lead White were detected. In the case of mixing the two pigments in the powder state, darkening did not occur even by the UV test. However, the specimens colored with the mixed powder were darkened by the UV test. The color change of Orpiment was different depending on the mixed pigment and base material. The color change was greater in the case of alum treatment than in the case without alum treatment, and it was found that alum also had an influence on the color change of Orpiment.

• Korean Journal of Occupational Health Nursing
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• v.11 no.1
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• pp.13-30
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• 2002

Industrial shift workers feels suffer mental stresses which are caused by unfamiliar day sleep, noisy environment, sleeping disorder by bright light, unusual contacts with family, difficulty in meeting with friends or having formal social meetings and other social limitations such as the use of transportation. Such stresses influence health of the workers negatively. Thus the health promotion policy for shift workers should be made considering the workers' ways of living and shift work specially. This study attempted to provide basic information for development of the health promotion program for industrial shift workers by examining predictive factors influencing health promotion behaviors of those workers. In designing the study, three power generation plants located in Pusan and south Kyungsang province were randomly selected and therefrom 280 workers at central control, boiler and turbine rooms and environmental chemistry parts whose processes require shift works were sampled as subjects of the study. Data were collected two times from September 17 to October 8, 1999 using questionnaires with helps of safety and health managers of the plants. The questionnaires were distributed through mails or direct visits. Means for the study included the measurement tool of health promotion behavior provided by Park(1995), the tool of self-efficacy measurement by Suh(1995), the tool of internal locus of control measurement by Oh(1987), the measurement tool of perceived health state by Park(1995) and the tool of social support measurement by Paek(1995). The collected data were analyzed using SPSS program. Controlling factors of the subjects were evaluated in terms of frequency and percentage ratio Perceived factors and health promotion behaviors of the subjects were done so in terms of mean and standard deviation, and average mark and standard deviation, respectively. Relations between controlling and perceived factors were analyzed using t-test and ANOVA and those between perceived factors and the performance of health promotion behaviors, using Pearson's Correlation Coefficient. The performance of health promotion behaviors was tested using t-test, ANOVA and post multi-comparison (Scheffe test). Predictive factors of health promotion behavior were examined through the Stepwise Multiple Regression Analysis. Results of the study are summarized as follows. 1. The performance of health promotion behaviors by the subjects was evaluated as having the value of mean, $161.27{\pm}26.73$ points(min.:60, max.:240) and average mark, $2.68{\pm}0.44$ points(min.:1, max.:4). When the performance was analyzed according to related aspects, it showed the highest level in harmonious relation with average mark, $3.15{\pm}.56$ points, followed by hygienic life($3.03{\pm}.55$), self-realization ($2.84{\pm}.55$), emotional support($2.73{\pm}.61$), regular meals($2.71{\pm}.76$), self-control($2.62{\pm}.63$), health diet($2.62{\pm}.56$), rest and sleep($2.60{\pm}.59$), exercise and activity($2.53{\pm}.57$), diet control($2.52{\pm}.56$) and special health management($2.06{\pm}.65$). 2. In relations between perceived factors of the subjects(self-efficacy, internal locus of control, perceived health state) and the performance of health promotion behaviors, the performance was found having significantly pure relations with self-efficacy (r=.524, P=.000), internal locus of control (r=.225, P=.000) and perceived health state(r=.244, P=.000). The higher each evaluated point of the three factors was, the higher the performance was in level. 3. When relations between the controlling factors(demography-based social, health-related, job-related and human relations characteristics) and the performance of health promotion behaviors were analyzed, the performance showed significant differences according to marital status (t=2.09, P= .03), religion(F=3.93, P= .00) and participation in religious activities (F=8.10, P= .00) out of demography-based characteristics, medical examination results (F=7.20, P= .00) and methods of the collection of health knowledge and information(F=3.41, P= .01) and methods of desired health education(F=3.41, P= .01) out of health-related characteristics, detrimental factors perception(F=4.49, P= .01) and job satisfaction(F=8.41, P= .00) out of job-related characteristics and social support(F=14.69, P= .00) out of human relations characteristics. 4. The factor which is a variable predicting best the performance of health promotion behaviors by the subjects was the self-efficacy accounting for 27.4% of the prediction, followed by participation in religious activities, social support, job satisfaction, received health state and internal locus of control in order all of which totally account for 41.0%. In conclusion, the predictive factor which most influence the performance of health promotion behaviors by shift workers was self-efficacy. To promote the sense, therefore, it is necessary to develop the nursing intervention program considering predictive factors as variables identified in this study. Further industrial nurses should play their roles actively to help shift workers increase their capability of self-management of health.

• The korean journal of orthodontics
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• v.31 no.2 s.85
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• pp.225-236
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• 2001

It is widely accepted that the shape and structure of bone are closely related to the activity of attached muscle. Numerous clinical and animal experimental studies indicated the significant effects of masticatory muscle function on maxillofacial morphology. Recently, the development of ultrasonography has spread throughout different fields of medicine. In the clinical examinations, ultrasonography is a convenient, inexpensive technique to apply with accurate and reliable results. The aim of this study is to assess the thickness of the masseter muscle and its correlation to maxillofacial skeleton by examining 35 male and 15 female dental students at Kangnung National University. The masseter muscle thickness of the subjects were measured by ultrasonographic scanning with a 7.5MHz linear probe, and their maxillofacial morphology were investigated by lateral cephalometric radiographs. The relationship between the masseter muscle thickness and maxillofacial morphology of normal adult was statistically analyzed, and the following results were obtained. 1. The average thickness of male masseter muscle was 13.8${\pm}$1.71mm in the relaxed state and 14.8${\pm}$1.77mm at maximal clenching state, while that of female was 11.6${\pm}$1.58mm and 12.4${\pm}$1.47mm, respectively. Ethnic difference in thickness of the masseter muscle and maxillofacial skeleton was found when the results of many researchers were compared with those of this study. 2. The thickness of the masseter muscle in both sexes increased significantly at maximal clenching state than in relaxed state(P<0.05). 3. The masseter muscle thickness of male was greater than that of female both in the relaxed state and maximal clenching states(P<0.05). 4. In males, the thickness of the masseter muscle was negatively correlated with the mandibular plane angle and positively correlated with the mandibular ramus height and anterior cranial base length(P<0.05). It may suggest that the male with thicker masseter muscle has smaller facial divergence. 5. No significant correlation was found between the masseter muscle thickness and maxillofacial morphology in females(P<0.05). Therefore, these data suggest that ultrasonography can add valuable information to the conventional examinations of masseter muscle function.

• Journal of the Korean Society for Marine Environment & Energy
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• v.13 no.3
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• pp.187-197
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• 2010

Carbon dioxide Capture and Storage(CCS) is regarded as one of the most promising options to response climate change. CCS is a three-stage process consisting of the capture of carbon dioxide($CO_2$), the transport of $CO_2$ to a storage location, and the long term isolation of $CO_2$ from the atmosphere for the purpose of carbon emission mitigation. Up to now, process design for this $CO_2$ marine geological storage has been carried out mainly on pure $CO_2$. Unfortunately the $CO_2$ mixture captured from the power plants and steel making plants contains many impurities such as $N_2$, $O_2$, Ar, $H_2O$, $SO_2$, $H_2S$. A small amount of impurities can change the thermodynamic properties and then significantly affect the compression, purification, transport and injection processes. In order to design a reliable $CO_2$ marine geological storage system, it is necessary to analyze the impact of these impurities on the whole CCS process at initial design stage. The purpose of the present paper is to compare and analyse the relevant physical property models including BWRS, PR, PRBM, RKS and SRK equations of state, and NRTL-RK model which are crucial numerical process simulation tools. To evaluate the predictive accuracy of the equation of the state for $CO_2-SO_2$ mixture, we compared numerical calculation results with reference experimental data. In addition, optimum binary parameter to consider the interaction of $CO_2$ and $SO_2$ molecules was suggested based on the mean absolute percent error. In conclusion, we suggest the most reliable physical property model with optimized binary parameter in designing the $CO_2-SO_2$ mixture marine geological storage process.

• Applied Chemistry for Engineering
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• v.20 no.3
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• pp.317-321
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• 2009

In order to analyze the high temperature phase formation and the sinterability of super ionic conductor $K^+-{\beta}/{\beta}"-Al_2O_3$ which is commonly used as a solid oxide electrolyte, the pure $K^+-{\beta}/{\beta}"-Al_2O_3$ powder in the ternary system $K_2O-LiO_2-Al_2O_3$ was synthesized by solid state reaction and formed to tube and disk using slip casting method and cold isostatic pressing (CIP), respectively. The slip casting was conducted in an alumina mold with the slurry containing 40 wt% of solid contents and the CIP was carried out under 20 MPa. The samples were sintered at $1600^{\circ}C$, $1700^{\circ}C$ and $1750^{\circ}C$, respectively, and their phase formation and the sintering density were investigated according to the forming method. The samples produced by CIP showed far higher ${\beta}"-Al_2O_3$ fraction as compared with those by slip casting. On the other hand, the samples by slip casting showed slightly higher sintering density. The relative density reached to about 83% at $1750^{\circ}C$ and for 1 h, independent of the forming method. In the case of 90 min socking time, the density was decreased owing to the exaggerated grain growth and the pores by $K_2O$ evaporation.