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A Study on the Application of EXPERT-CHOICE Technique for Selection of Optimal Decontamination Technology for Nuclear Power Plant of Decommissioning (원전 해체 시 최적 제염기술 선정을 위한 EXPERT-CHOICE 기법 적용에 대한 연구)

  • Song, Jong Soon;Shin, Seung Su;Lee, Sang Heon
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.15 no.3
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    • pp.231-237
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    • 2017
  • The present study researched and analyzed decontamination technology for decommissioning a nuclear power plant. The decision-making technique (EXPERT-CHOICE) was used to evaluate and select the optimal decontamination technology. In principle, this evaluation method is generally performed by a group of experts in the relevant field. The results of the weights were calculated by multiplying the weights with regard to each criterion and evaluation score. The evaluation scores were categorized into 3 ranges (high, medium, and low), and each range was weighted for differentiation. The level of the technology analysis was improved by additionally quantifying the weights with regard to each criterion and subdividing criteria into subcriteria. The basic assumption of the evaluation was that the weight values would decided on in an expert survey and assigned to each criterion. The evaluation criteria followed high weight for the 'High' range. Accordingly, H, M, and L were assigned weights of 10:5:1, respectively. This was based on the EXPERT-CHOICE optimal analysis. The minimum and maximum values were excluded, and the average value was used as the evaluation value for each scenario.

The Fatigue Life Evaluation of Aged Continuous Welded Rail on the Urban Railway (도시철도 장기 사용레일의 피로수명 평가)

  • Kong, Sun-Young;Sung, Deok-Yong;Park, Yong-Gul
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.2
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    • pp.821-831
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    • 2013
  • As a result of recent research, it is reported that the periodic replacements criterion of rails is able to extend as grinding rail surface and using the continuous welded rail (CWR). In this study, we carried out fatigue tests on existing laid rails. Based on the test results, an S-N curve expressing the remaining life of laid rails at a fracture probability of 50% was obtained using weighted probit analysis suitable for small-sample fatigue data sets. As rails used for testing had different histories in terms of accumulated tonnage, the test data were corrected to average out the accumulated tonnage. We estimated the remaining service lives for laid rails on the urban railway using equations developed in the past to estimate rail base bending stress and that surface irregularities into consideration. Therefore, estimating the remaining service life of laid rails showed that the rail replacement period could be extended over 200 MGT, although it is necessary to remove longitudinal rail surface irregularities at welds by grinding. Also, the fatigue test results under fatigue limit, Haibach's rule appling half slope of S-N curve under the fatigue limit was considered more reasonable than modified Miner's rule for estimating rail fatigue life.

Study of Low Reflectance and RF Frequency by Rie Surface Texture Process in Multi Crystall Silicon Solar Cells (공정가스와 RF 주파수에 따른 웨이퍼 표면 텍스쳐 처리 공정에서 저반사율에 관한 연구)

  • Yun, Myoung-Soo;Hyun, Deoc-Hwan;Jin, Beop-Jong;Choi, Jong-Young;Kim, Joung-Sik;Kang, Hyoung-Dong;Yi, Jun-Sin;Kwon, Gi-Chung
    • Journal of the Korean Vacuum Society
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    • v.19 no.2
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    • pp.114-120
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    • 2010
  • Conventional surface texturing in crystalline silicon solar cell have been use wet texturing by Alkali or Acid solution. But conventional wet texturing has the serious issue of wafer breakage by large consumption of wafer in wet solution and can not obtain the reflectance below 10% in multi crystalline silicon. Therefore it is focusing on RIE texturing, one method of dry etching. We developed large scale plasma RIE (Reactive Ion Etching) equipment which can accommodate 144 wafers (125 mm) in tray in order to provide surface texturing on the silicon wafer surface. Reflectance was controllable from 3% to 20% in crystalline silicon depending on the texture shape and height. We have achieved excellent reflectance below 4% on the weighted average (300~1,100 nm) in multi crystalline silicon using plasma texturing with gas mixture ratio such as $SF_6$, $Cl_2$, and $O_2$. The texture shape and height on the silicon wafer surface have an effect on gas chemistry, etching time, RF frequency, and so on. Excellent conversion efficiency of 16.1% is obtained in multi crystalline silicon by RIE process. In order to know the influence of RF frequency with 2 MHz and 13.56 MHz, texturing shape and conversion efficiency are compared and discussed mutually using RIE technology.

Analysis of Rainfall Effect on the GIUH Characteristic Velocity (GIUH 특성속도에 대한 강우의 영향 분석)

  • Kim, Kee-Wook;Roh, Jung-Hwan;Jeon, Yong-Woon;Yoo, Chul-Sang
    • Journal of Korea Water Resources Association
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    • v.36 no.4
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    • pp.533-545
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    • 2003
  • This study analyzed several storm events observed in the Seolma-chun basin to derive the characteristic velocity of GIUH (Geomophological Instantaneous Unit Hydrograph) as well as its variability. Especially, this study focused on the variation of characteristic velocity due to the change of rainfall characteristics. The IUH of the Seolma-chun basin was derived using the HEC-1, whose peak discharge and time were then compared with those of the GIUH to derive the characteristic velocities. The characteristics velocities were analyzed by comparing with the GcIUH (Geomorphoclimatic IUH) as well as the characteristics of rainfall. Results are summarized as follows. (1) The characteristic velocity of GIUH was estimated higher with higher variability than the GcIUH, but their trends were found similar (2) Total amount of effective rainfall (or, mean effective rainfall) well explains the characteristic velocity of GIUH. This could be assured by the regression analysis, whose coefficient of determination was estimated about 0.6. (3) The duration and the maximum intensity of rainfall were found not to affect significantly on the characteristic velocity of GIUH. The coefficients of determination were estimated less than 0.3 for all cases considered. (4) For the rainfall events used in this study, the characteristic velocities of GIUH were found to follow the Gaussian distribution with its mean and the standard deviation 0.402 m/s and 0.173 m/s, respectively. Most of the values are within the range of 0.4∼0.5 m/s, and its coefficient of variation was estimated to be 0.43, much less than that of the runoff itself (about 1.0).

The Relationship between Stand Mean DBH and Temperature at a Watershed Scale: The Case of Andong-dam Basin (유역단위에서의 임목평균흉고직경과 기온 간의 관계: 안동댐 유역을 중심으로)

  • Moon, Jooyeon;Kim, Moonil;Lim, Yoonjin;Piao, Dongfan;Lim, Chul-Hee;Kim, Seajin;Song, Cholho;Lee, Woo-Kyun
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.18 no.4
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    • pp.287-297
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    • 2016
  • This study aims to identify the relationship between climatic factors and stand mean Diameter at Breast Height (DBH) for two major tree species; Pinus densiflora and Quercus mongolica in Andong-dam basin. Forest variables such as age, diameter distribution and number of trees per hectare from the $5^{th}$ and $6^{th}$ National Forest Inventory data were used to develop a DBH estimation model. Climate data were collected from six meteorological observatory station and twelve Automatic Weather System provided by Korea Meteorological Administration to produce interpolated daily average temperature map with Inverse Distance Weighting (IDW) method. Andong-dam basin reflects rugged mountainous terrain, so temperature were adjusted by lapse rate based correction. As a result, predictions of model were consistent with the previous studies; that the rising temperature is negatively related to the growth of Pinus densiflora whereas opposing trend is observed for Quercus mongolica.

A Study on the Build-up Model for the Discount Rate of Technology Valuation including Intellectual Property Risk (지식자산위험을 고려한 기술가치평가 할인율 적산모형에 관한 연구)

  • Sung, Oong-Hyun
    • Journal of Korea Technology Innovation Society
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    • v.11 no.2
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    • pp.241-263
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    • 2008
  • Within any income approach, a discount rate is used to convert some projected free cash flow to its presented value. In case of valuing companies, the most frequently used discount rate is the weighted average cost of capital(WACC) at the aggregate level. But technology valuation is different to discounting aggregate corporate cash flow since it is concerned about individual Intellectual property. Therefore, blindly applying standard discount rate such as WACC in technology valuation is unlikely to lead to the right result. The primary focus of this paper is to establish the structure of discount rate for technology valuation and to suggest the method of estimation. To determine an appropriate discount rate for technology valuation, the level of technology risk, market risk and competitive risk should be included in the structure of discount rate. This paper suggests the build-up model which consists of three components as a expansion of the CAPM. It includes (1) a risk-free rate of return, (2) general market risk premium and beta and (3) intellectual property risk premium related to technology risk and specific target market risk. However, there is no specific check list for examining the intellectual property risk until now and no specific method for quantifying its risk into risk premium. This paper developed the 10 element to determine the level of the intellectual property risk and applied estimation function such as linear function, natural log function and exponential function to transform the level of risk into risk premium. The limitation of this paper is that the range of intellectual property risk premium is inferred based on the information of foreign and domestic valuation agency. Finally, this paper explored the development of an intellectual property discount rate for technology valuation and presented the method in order to quantify the intellectual property risk premium.

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The Study on Development of R&D Technology Rating Methodology in the Defense Area (국방 R&D기술 등급평가 방법론 개발 연구)

  • Jung, You-Jin;Kim, Joon-Young;Joung, Tae-Yun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.2
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    • pp.158-167
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    • 2017
  • This paper presents the technology rating methodology that is applicable to defense R&D technology. First, a technology profitability index was developed using multiple regression analysis to forecast the revenue from technology transfer. Secondly, the technology evaluation index was derived using hierarchical analysis with expert opinion. Finally, the weighted average of the technology profitability index and technology evaluation index were calculated to derive the technology rating. This study is significant in that it is first attempt to evaluate defense R&D technology by rating. If the defense R&D technology rating methodology is applied in practice, it can contribute to efficient R&D budget allocation. In addition, it will help in the vitalization of technology transfer in the defense R&D sector.

Duplicated ECG signal decomposition (이중 심전도 신호의 분리 방법)

  • Kim, Do-Yeon;Kang, Hyun-Soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.2
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    • pp.414-421
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    • 2015
  • This paper presents a new method to decompose a duplicated ECG signal, which is measured from two people, to two individual ECG signals. In paper, it is shown that the duplicated ECG signal can be decomposed, provided that their SAECG signals are known. As the SAECG signal is the average of a ECG signal, it is a feature to identify individual ECG signals from the duplicated signal. Since the ECG signal is nearly periodic, so-called heart-rate, the period of each ECG signal can be found by using the autocorrelation of the duplicated signal, That is, the autocorrelation has high peaks at the multiple instants of heart-rate of each person. With the heart-rate of each person obtained by some processing, all R-peaks are identified by the SAECG signals. To be concrete, the SAECG signal of each person is repeatedly placed at the R-peak instants with his heart-rate, and the weight of each SAECG signal is computed by LMSE optimization. Finally, as adding the error signal in the LMSE optimization processing to the weighted SAECG signal, each individual ECG signal is obtained. In experimental results, we demonstrate that the duplicated ECG signal is successfully decomposed into two ECG signals.

Estimating the Cost Savings Due to the Effect of Kremezin in Delaying the Initiation of Dialysis Treatments among Patients with Chronic Renal Failure (크레메진의 투석도입 지연효과에 따른 진행성 신부전증환자의 비용감소분 추계)

  • Cho, Woo-Hyun;Lee, Sun-Mi;Kim, Hyung-Jong;Lee, Ho-Yong;Woo, Tae-Wook;Kang, Hye-Young
    • Journal of Preventive Medicine and Public Health
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    • v.39 no.2
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    • pp.149-158
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    • 2006
  • Objectives : We wanted to evaluate the economic value of a pharmaceutical product, Kremezin, for treating patients with chronic renal failure (CRF) by estimating the amount of cost savings due to its effect for delaying the initiation of dialysis treatments. Methods : We defined a conventional treatment for CRF accompanied by Kremezin therapy as 'the treatment group' and only conventional treatment as 'the alternative group.' The types of costs included were direct medical and nonmedical costs and costs of productivity loss. The information on the effect of Kremezin was obtained from the results of earlier clinical studies. Cost information was derived from the administrative data for 20 hemodialysis and 20 peritoneal dialysis patients from one tertiary care hospital, and also from the administrative data of 10 hemodialysis patients from one free-standing dialysis center. Per-capita cost savings resulting from Kremezin therapy were separately estimated for the cases with delay for the onset of hemodialysis and the cases with immediate performance of peritoneal dialysis. By computing the weighted average for the cases of hemodialysis and peritoneal dialysis, the expected per-capita cost savings of a patient with CRF was obtained. Using a discount rate of 5%, future cost savings were converted to the present value. Results : The present value of cumulative cost savings per patient with CRF from the societal perspective would be $18,555,000{\sim}29,410,000$ Won or $72,104,000{\sim}112,523,000$ Won if Kremezin delays the initiation of dialysis by 1 or 4 years. Conclusions : The estimated amount of cost savings resulting from treating CRF patients with Kremezin confirms that its effect for delaying the onset of dialysis treatments has a considerable economic value.

A Study on Predictive Traffic Information Using Cloud Route Search (클라우드 경로탐색을 이용한 미래 교통정보 예측 방법)

  • Jun Hyun, Kim;Kee Wook, Kwon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.33 no.4
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    • pp.287-296
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    • 2015
  • Recent navigation systems provide quick guide services, based on processing real-time traffic information and past traffic information by applying predictable pattern for traffic information. However, the current pattern for traffic information predicts traffic information by processing past information that it presents an inaccuracy problem in particular circumstances(accidents and weather). So, this study presented a more precise predictive traffic information system than historical traffic data first by analyzing route search data which the drivers ask in real time for the quickest way then by grasping traffic congestion levels of the route in which future drivers are supposed to locate. First results of this study, the congested route from Yang Jae to Mapo, the analysis result shows that the accuracy of the weighted value of speed of existing commonly congested road registered an error rate of 3km/h to 18km/h, however, after applying the real predictive traffic information of this study the error rate registered only 1km/h to 5km/h. Second, in terms of quality of route as compared to the existing route which allowed for an earlier arrival to the destination up to a maximum of 9 minutes and an average of up to 3 minutes that the reliability of predictable results has been secured. Third, new method allows for the prediction of congested levels and deduces results of route searches that avoid possibly congested routes and to reflect accurate real-time data in comparison with existing route searches. Therefore, this study enabled not only the predictable gathering of information regarding traffic density through route searches, but it also made real-time quick route searches based on this mechanism that convinced that this new method will contribute to diffusing future traffic flow.