• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.3
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• pp.171-178
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• 2008

Metal filter elements were newly introduced to the high temperature filter(HTF) system in the low- and intermediate-level radioactive waste vitrification plant. In order to evaluate the performance of various metal materials as filter media, elements made of AISI 316L, AISI 904L, and Inconel 600 were included to the test set of filter elements. At the visual inspection to the elements performed after completion of each test, a few dark spots were observed on the surface of some elements. Especially they were found much more at the AISI 316L elements than others. To check the dark spots are the corrosion phenomena or not, two kinds of analyses were performed to the tested filter elements. Firstly, the surfaces or the cross sections of filter specimens cut out from both normal area and dark spot area of elements were analyzed by SEM/EDS. The results showed that the dark spots were not evidences of corrosion but the deposition of sodium, sulfur and silica compounds volatilized from waste or molten glass. Secondly, the ring tensile strength were analyzed for the ring-shape filter specimens cut out from each kind of element. The result obtained from the strength tested showed no evidence of corrosion as well. Conclusionally, depending on the two kinds of analysis, no evidences of corrosion were found at the tested metal filter elements. But the dark spots formed on the surface could reduce the effective filtering area and increase the overall pressure drop of HTF system. Thus, continuous heating inside filter housing up to dew point will be required normally. And a few long-period test should be followed for the exact evaluation of corrosion of the metal filter elements.

• The Journal of Korean Society for Radiation Therapy
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• v.23 no.1
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• pp.13-19
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• 2011

Purpose: It's essential to minimize the tumor motion and identify the exact location of the lesions to achieve the improvement in radiation therapy efficiency during SBRT. In this study, we made the established compression belt to reduce respiratory motion and evaluated the usefulness of clinical application in SBRT. Materials and Methods: We analyzed the merits and demerits of the established compression belt to reduce the respiratory motion and improved the reproducibility and precision in use. To evaluate the usefulness of improved compression belt for respiratory motion reduction in SBRT, firstly, we reviewed the spiral CT images acquired in inspiration and expiration states of 8 lung cancer cases, respectively, and analyzed the three dimensional tumor motion related to respiration. To evaluate isodose distribution, secondly, we also made the special phantom using EBT2 film (Gafchronic, ISP, USA) and we prepared the robot (Cartesian Robot-2 Axis, FARARCM4H, Samsung Mechatronics, Korea) to reproduce three dimensional tumor motion. And analysis was made for isodose curves and two dimensional isodose profiles with reproducibility of respiratory motion on the basis of CT images. Results: A respiratory motion reduction compression belt (Velcro type) that has convenient use and good reproducibility was developed. The moving differences of three dimensional tumor motion of lung cancer cases analyzed by CT images were mean 3.2 mm, 4.3 mm and 13 mm each in LR, AP and CC directions. The result of characteristic change in dose distribution using the phantom and rectangular coordinates robot showed that the distortion of isodose has great differences, mean length was 4.2 mm; the differences were 8.0% and 16.8% each for cranio-caudal and 8.1% and 10.9% each for left-right directions in underdose below the prescribed dose. Conclusion: In this study, we could develop the convenient and efficient compression belt that can make the organs' motion minimize. With this compression belt, we confirmed that underdose due to respiration can be coped with when CTV-PTV margins of mean 6 mm would be used. And we conclude that the respiratory motion reduction compression belt we developed can be used for clinical effective aids along with the gating system.

• The Journal of Korean Society for Radiation Therapy
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• v.23 no.2
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• pp.83-90
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• 2011

Purpose: This study statistically analyzed the difference of the stability of maintaining a respiratory period shown according to position and use of a device to search the tendency and usefulness of a device. Materials and Methods: The study obtained respiratory signals which maintained a respiratory period for 20 minutes each supine and prone position for 11 subjects. The study obtained respiratory signals in a state of using a belly board for 7 patients in a bad condition of a respiratory period in a prone position to analyze a change in respiration and the stability before and after the use of a device. Results: The supine part showed 54.5%, better than the prone part of 36.4% in a case that the stability for maintaining a respiratory period was in a good condition as a fixed respiratory period was well maintained according to the position. 6 patients (85%) showed a maintenance pattern of a respiratory period significantly different before the use and 4 patients showed a significantly good change in the stability for maintaining a respiratory period as a result that belly boards were used for 7 patients that the maintenance of a respiratory period was not in a good condition on a prone position. Conclusion: It seemed that this study could contribute to the maintenance of respiratory period and of respiratory stability as the optimal position for maintenance of respiration and the use of a device such as a belly board were decided through statistic analysis of respiratory signals and its application even if patient position and use of device were decided by the beam arrangement a treatment part of a patient, location of a target, and an expected plan.

• The Journal of Korean Society for Radiation Therapy
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• v.19 no.2
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• pp.123-129
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• 2007

Purpose: CT scan shows that significant tumor movement occurs in lesions located in the proximity of the heart, diaphragm, and lung hilus. There are differences concerning three kinds of type to get images following the Scan type called Axial, Helical, Cine (4D-CT) mode, when the scanning by CT. To know how each protocol describe accurately, this paper is going to give you reappearance using the moving phantom. Materials and Methods: To reconstruct the movement of superior-inferior and anterior-posterior, the manufactured moving phantom and the motor following breathing were used. To distinguish movement from captured images by CT scanning, a localizer adhered to the marker on the motor. The moving phantom fixed the movement of superior-inferior upon 1.3 cm /1 min. The motor following breathing fixed the movement of anterior-posterior upon 0.2 cm /1 min. After fixing each movement, CT scanning was taken by following the CT protocols. The movement of A localizer and volume-reappearance analyzed by RTP machine. Results: Total volume of a marker was 88.2 $cm^3$ considering movement of superior-inferior. Total volume was 184.3 $cm^3$. Total volume according to each CT scan protocol were 135 $cm^3$ by axial mode, 164.9 $cm^3$ by helical mode, 181.7 $cm^3$ by cine (4D-CT) mode. The most closely describable protocol about moving reappearance was cine mode, the marker attached localizer as well. Conclusion: CT scan should reappear concerning a exact organ-description and target, when the moving organ is being scanned by three kinds of CT protocols. The cine (4D-CT) mode has the advantage of the most highly reconstructible ability of the three protocols in reappearance of the marker using a moving phantom. The marker on the phantom has always regular motion but breathing patients don't move like a phantom. Breathing education and devices setting patients were needed so that images reconstruct breathing as exactly as possible. Users should also consider that an amount of radiation to patients is being bombed.

• Journal of Korean Orthopaedic Sports Medicine
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• v.4 no.1
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• pp.18-28
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• 2005

Purpose: The purpose of this study is to evaluate the clinical, radiological and histopathological results after microfracture surgery for degenerative arthritis of the knee. Materials and Methods: From Oct. 1997 to Dec. 1998, 48 knees in 46 patients were treated by microfracture technique. Their mean age at the time of operation was 56 years(range, 40-75 years) and mean period of follow-up study was one year(range, 7-20 months). For 24 knees in 22 patients, 'second-look' arthroscopies and biopsies were performed at 6 months following microfracture. At the last follow up clinical results were evaluated with Baumgaertner's scale. The specimens of 24 cases were stained with H-E, Safranin-O, and Masson's trichrome. Eighteen of 24 cases were stained immunohistochemically and the Western blotting test was performed on 12 cases for type II collagen. We analyzed the relationship of the Western blotting for type II collagen with clinical score, preoperative varus deformity, joint space widening in radiological result, extent of repaired articular cartilage in '2nd-look' arthroscopic findings, patient's age and weight. Results: Clinical results were excellent in 90% and good in 10%. Among the 24 knees, more than 80% of areas of chondral defect were covered with regenerated cartilage in 21 knees Histologically, the repaired tissue appears to be a hybrid of hyaline cartilage and fibrocartilage. Repaired cartilage contains variable amounts of type II collagen with immunohistochemical staining. The results of the Western blotting test were similar. The amounts of type II collagen formation had positive correlation with the extent of repaired cartilage and preoperative varus deformity. Conclusion: 'Second-look' showed that the chondral defect areas were covered with newly grown grayish white tissue. Articular cartilage repair was confirmed with histological and immunohisto-chemical study qualitatively, and the amount of type II collagen was calculated with the Western blotting test quantitatively. The exact nature and fate of repaired cartilagenous tissues need further long term follow-up study. The results of this study provide the rationale to select osteoarthritic patients indicated for microfracture surgery.

• The Journal of Industrial Distribution & Business
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• v.1 no.1
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• pp.23-31
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• 2010

In this study, market orientation affects the real estate transaction and about the various parameters examined, the real estate transactions, market orientation and intensity of competition in the market upheaval and the impact was seen on the results can be summarized as follows. First, market orientation and about the relationship between real estate transactions were examined. Each variable of customer satisfaction information generation, information dissemination, information was used for the reaction. Among them, the dissemination of information, information about the reaction produces a lot better the customer satisfaction was the result. In other words, the dissemination of information and availability of information to real estate transactions, the more you can improve customer satisfaction. While the information does not appear to be generated as a result of the impact of market orientation when the first phase of the creation of market information and the customer's needs and preferences of current and future information and external factors affecting them to gather information about It is difficult to assess realistically can be seen. This is both our customers and dealers in real estate purchase or trade items for the exact targets, but the general approach the start of trading because by necessity. Therefore, a clear standard for real estate deals in and nine minutes to all sellers of real estate purchases through a process of communication to enable effective approach should be. Second, market orientation and about the relationship between real estate transactions were examined. The information for each variable in re-creating transactions, information dissemination, information was used for the reaction. Variable affects all the information creation, dissemination of information, information about the reaction the better the deal re-done show that two can be frequent. In other words, information generation, information dissemination and utilization of information to real estate transactions, the more customers the added responsibilities of the re-trade can be seen. Third, the relationship between market orientation and in the real estate market upheaval of environmental factors on the relationship between gender were examined. Each variable of customer satisfaction information generation, information dissemination, information was used for the reaction. Among them, the dissemination of information, information about the reaction produces a lot better the customer satisfaction was the result. In other words, the dissemination of information, depending on the market upheaval and the availability of information to raise the real estate can increase customer satisfaction. Fourth, market orientation and environmental factors in the relationship between real estate transactions and about the relationship between competition intensity was investigated. The information for each variable in re-creating transactions, information dissemination, information was used for the reaction. Variable affects all the information creation, dissemination of information, information about the reaction the better the deal re-done show that two can be frequent. In other words, information generation, information dissemination and utilization of information and the higher intensity of competition or unyounghameusseo ttaemaewoo active real estate transactions to provide our customers the added responsibilities of the re-trade can be seen. If more comprehensive, market orientation, according to real estate transactions and environmental factors affecting the performance was also different. Abundance of information about the current real estate it is true that the accuracy and reliability, and real estate, and are unsure about the expected benefits. So you want to trade to provide accurate information to customers and markets change rapidly and competition is severe, with more information if you have reliable information to the customer must supply can increase trading performance. Guarantee of future customer transactions and can provide valuable information and research needs to be differentiated based on the provision of real estate information should be done to achieve profitability will be a cow brokerage.

• Restorative Dentistry and Endodontics
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• v.32 no.5
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• pp.469-475
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• 2007

The purpose of this study was to evaluate the effect of a new resin monomer on the microleakage of composite resin restorations. By adding new methoxylated Bis-GMA (Bis-M-GMA, 2,2-bis[4-(2-methoxy-3-methacryloyloxy propoxy) phenyl] propane) having low viscosity, the content of TEGDMA which has adverse effects on polymerization shrinkage might be decreased. As a result, microleakage might be improved. $2\;mm\;{\times}\;2\;mm\;{\times}\;2\;mm$ cavities with occlusal margins in enamel and gingival margins in dentin were prepared on buccal and lingual surfaces of 40 extracted human premolars. Prepared teeth were randomly divided into four groups and restored with Clearfil SE bond (Kuraray, Japan) and one of experimental composite resins; EX1, Experimental composite resin1 (Bis-M-GMA/TEGDMA = 95/5 wt%, 40 mm nanofillers); EX2, Experimental composite resin2 (Bis-M-GMA/TEGDMA = 95/5 wt%, 20 mm nanofillers); EX3, Experimental composite resin3 (Bis-GMA/TEGDMA = 70/30 wt%, 40 nm nanofillers); and Filtek Z250 (3M ESPE, USA) was filed as a control group. The restored teeth were thermocycled, and immersed in 2% methylene blue solution for 24 hours. The teeth were sectioned buccolingually with a low speed diamond saw and evaluated for microleakage under stereomicroscope. The data were statistically analyzed by Pearson Chi-Square test and Fisher Exact test (p = 0.05). The microleakage scores seen at the enamel margin were significantly lower than those of dentin margin (p = 0.007). There were no significant differences among the composite resins in the microleakage scores within each margin (p > 0.05). Bis-M-GMA, a new resin monomer having low viscosity, might in part replace high viscous Bis-CMA and might improve the quality of composite resin.

• The Journal of the Korea Contents Association
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• v.9 no.11
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• pp.151-162
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• 2009

The objective of this study is to uncover the standard and procedure of the review for the online game to export to China and try to find a plan how to solve a problem such as regulation for the online game imported into China depending on a protective policy for homemade game. The literatures related to the policy of China online game industry and the present condition of the wholistic restriction are reviewed and the standard and procedure of the review of China online game which is veiled was able to find definitely by using the case study on Korean company which was a great success as localization in China. As a result of this study, we found that the key factor on the review standard of China online game is the anti-social personality, such as 'the overthrow of Chinese socialist system', 'the territorial issue as the eviction of Hong Kong or the acknowledgment of Taiwan government', 'independence problem of the minorities', and 'damage to property as national treasure', et cetera. While the review of the homemade game in China takes about a month through just two steps in review process on online game, that of foreign game is required over at least three months through four steps in it. Moreover, it is difficult for foreign games to obtain the license due to total amount regulation for online game by 'General Administration of Press and Publication of the People's the Republic of China'. In the case of the joint-venture company, it is most important to the smooth communication between Korean company and Chinese company in order to overcome these strong regulation for online game review in China. Furthermore, as Chinese company in outward appearance it is need to be positioned absolutely in Chinese marketplace. The definite positioning strategy enables foreign companies to avoid the strong regulation about the foreign game in China. To understand, finally, deeply politics, society, and culture presented in Chinese ethics textbook permits the foreign companies to predict the exact standard of the review for online game. Therefore, this study is concluded with key implications to sustain guidelines on the deliberation for foreign companies which want to export online game to China to improve the predictability and accountableness about the review of the online game in China.

• Journal of Intelligence and Information Systems
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• v.17 no.3
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• pp.187-201
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• 2011

KOSPI200 index is the Korean stock price index consisting of actively traded 200 stocks in the Korean stock market. Its base value of 100 was set on January 3, 1990. The Korea Exchange (KRX) developed derivatives markets on the KOSPI200 index. KOSPI200 index futures market, introduced in 1996, has become one of the most actively traded indexes markets in the world. Traders can make profit by entering a long position on the KOSPI200 index futures contract if the KOSPI200 index will rise in the future. Likewise, they can make profit by entering a short position if the KOSPI200 index will decline in the future. Basically, KOSPI200 index futures trading is a short-term zero-sum game and therefore most futures traders are using technical indicators. Advanced traders make stable profits by using system trading technique, also known as algorithm trading. Algorithm trading uses computer programs for receiving real-time stock market data, analyzing stock price movements with various technical indicators and automatically entering trading orders such as timing, price or quantity of the order without any human intervention. Recent studies have shown the usefulness of artificial intelligent systems in forecasting stock prices or investment risk. KOSPI200 index data is numerical time-series data which is a sequence of data points measured at successive uniform time intervals such as minute, day, week or month. KOSPI200 index futures traders use technical analysis to find out some patterns on the time-series chart. Although there are many technical indicators, their results indicate the market states among bull, bear and flat. Most strategies based on technical analysis are divided into trend following strategy and non-trend following strategy. Both strategies decide the market states based on the patterns of the KOSPI200 index time-series data. This goes well with Markov model (MM). Everybody knows that the next price is upper or lower than the last price or similar to the last price, and knows that the next price is influenced by the last price. However, nobody knows the exact status of the next price whether it goes up or down or flat. So, hidden Markov model (HMM) is better fitted than MM. HMM is divided into discrete HMM (DHMM) and continuous HMM (CHMM). The only difference between DHMM and CHMM is in their representation of state probabilities. DHMM uses discrete probability density function and CHMM uses continuous probability density function such as Gaussian Mixture Model. KOSPI200 index values are real number and these follow a continuous probability density function, so CHMM is proper than DHMM for the KOSPI200 index. In this paper, we present an artificial intelligent trading system based on CHMM for the KOSPI200 index futures system traders. Traders have experienced on technical trading for the KOSPI200 index futures market ever since the introduction of the KOSPI200 index futures market. They have applied many strategies to make profit in trading the KOSPI200 index futures. Some strategies are based on technical indicators such as moving averages or stochastics, and others are based on candlestick patterns such as three outside up, three outside down, harami or doji star. We show a trading system of moving average cross strategy based on CHMM, and we compare it to a traditional algorithmic trading system. We set the parameter values of moving averages at common values used by market practitioners. Empirical results are presented to compare the simulation performance with the traditional algorithmic trading system using long-term daily KOSPI200 index data of more than 20 years. Our suggested trading system shows higher trading performance than naive system trading.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.33 no.3
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• pp.197-201
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• 2007

Oil soluble licorice extract(licorice extract) is an officially approved cosmetic component as a whitening ingredient in Korea. The durability of licorice, during which the whitening effect can be maintained in optimum condition, must be accurately defined. Since the cosmetics durability under real condition is relatively longer than its development time. It is needed to predict the real durability interval from the experimental measurement under simulated operating conditions. We analyzed the relationship between the licorice lifetime and the high temperature condition by using Arrhenius equation. We have established the constant stress test with temperature of $50^{\circ}C$, $55^{\circ}C$, and $60^{\circ}C$ condition, within which no formulation change of licorice products is expected for the accelerated stress test. In this paper, the lifetime of licorice in cosmetics was defined as time period for its 10% contents reduction. We observed that the lifetime of licorice is 580 h at $50^{\circ}C$, 319 h at $55^{\circ}C$ and 166 h at $60^{\circ}C$. Using the above experimental data, we obtained the equation for the relationship between the licorice lifetime and temperature as follows; log(lifetime)=-35.0243 + 1.15322$\times$(11604.83/temperature). From this equation, the lifetime of licorice at $25^{\circ}C$ can be estimated as 26 months. The estimated result was verified by measuring full lifetime of licorice. In fact, there was no significant difference between the estimated lifetime and real measurement within 95 % significance level. This study can be applied to other useful cosmetic components for the fast estimation of the exact durability.