• Journal of Advanced Marine Engineering and Technology
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• v.23 no.5
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• pp.671-677
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• 1999

This study has been performed to investigate REW(relative electrode wear) in condition of vari-ous pulse-on duration using the copper and graphite electrode with change of the electrode size on the heat treated STD11 which is extensively used for metallic molding steel with the EDM. The results obtained are as follows; a) Graphite has much benefits than copper electrode when rapid machining is done without electrode wear, b) Neative REW result from the electrode that is very liable attach to decomposition carbide c)Increasing of machining time cause to increase wear length of the copper electrode and decrease wear length of the graphite electorde d)The more pulse-on duration copper electrode has the less REW. e) The edge portion of the electorde wears remarkably at the beginning of machining,.

• Journal of Chest Surgery
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• v.26 no.7
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• pp.521-525
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• 1993

Sixty-three patients who underwent open mitral commissurotomy at Sejong General Hospital during last 10 years from the August, 1983 to June, 1993 were reviewed There were fifty-one women and twelve men, and the mean age was 34.2 years. According to the NYHA classification, the distribution of patient preoperatively was as follows: class I, 5 patients ; class II, 26 patients ; class III, 30 patients ; class IV, 2 patients, and mean duration of symptome was 4.5 years. The mean mitral valvular area measured with echocardiogram preoperatively was 0.92cm2. All patients underwent open mitral commissurotomy and 41 patients required additional procedures for relief of subvalvular stenosis or other valvular disease. There were no operative death. 63 patients had three different types of mitral stenosis : type I, mobile cusps without subvalvular change [21 patients] ; typeII, thickened cusps with subvalvular change [34 patients] ; type III, rigid cusps with severe subvalvular change [8 patients]. The valvular calcification was seen in 11 patients [17%] and 15 patients [24%] had left atrial thrombus. The duration of follow-up was from 1 month to 168 months [mean, 39.6 months] and there were no late death. Six patients required reoperation and one patient had embolic episode. Conclusively,the open mitral commissurotomy represents a safe surgical precedure for treating mitral stenosis, allowing a complete removal of atrial thrombosis if present, and even when associated with subvalvular changes.

• Proceedings of the KIEE Conference
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• 1989.07a
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• pp.162-165
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• 1989

This paper describes an algorithm of P-wave detection by significant point extraction method with digital differentiation. P-waves are detected by pattern matching algorithm with significant points. By means of defecting onset and offset points of P-waves, this algorithm can measure the PR intervals exactly which is important to diagnosis the atrial arrhythmia. Because P-wave duration is changed according to heart-rates, we calculate the R-R interval prior to the determination of P-wave duration threshold values in order to actively adapt to the change of P duration The results obtained from the proposed algorithm have defected successfully P-wave almost more than 90%.

• MALSORI
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• no.47
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• pp.141-151
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• 2003

The speech intelligibility of congenitally deafened children shows the change after cochlear implantation. The predicting factors of change in speech intelligibility are the age of implantation, the duration of implant use, and communication mode etc.. Among these factors, the age of implantation seems to be one of the most important predictors. But those factors including age of implantation can explain only some parts of the variance. Therefore, the further study to find the factors which affect the speech intelligibility should be done.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.31 no.1
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• pp.24-28
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• 1995

Exercise physiology of fish was studied by means of Electro-cardio-gram(ECG) technique with wired electrode system. Effects of swimming activity on the heart rate change for carp Cyprinus carpio was observed and analysed under swimming speeds among 1~3 Body Length/s and swimming durations of 10 and 60 minutes in the flume tank. The heart rate increase during swimming activity was observed in higher speed and longer duration conditions. The exercise effect on the heart rate continued even after fish stopped swimming. The time for recovery after exercise was tended to be elongated with the higher exercise condition.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.8
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• pp.599-604
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• 2012

Most air pollution and smog are a result of the burning of fossil fuels. The use of fossil fuels also causes acid rain and global warming. So the need for solar energy utilization is increased. It is essentially important to make efforts to reduce usage of fossil energy resources. In this study, we analyzed the correlation between climatic elements(Cloud cover, Duration of sunshine, Temperature) and the photovoltaic power generation. Cloud cover of the correlation coefficient was 0.87. And duration of sunshine of the correlation coefficient was 0.93. The order of the correlation coefficient was duration of sunshine, cloud cover, temperature. To accurately analyze of the degree of correlation for the photovoltaic power generation, additional research about climatic elements that show a high correlation is needed.

• Journal of Korea Water Resources Association
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• v.52 no.1
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• pp.71-82
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• 2019

The purpose of this study is to analyze the Mekong River streamflow alteration due to climate change. The future climate change scenarios were produced by bias corrections of the data from East Asia RCP 4.5 and 8.5 scenarios, given by HadGEM3-RA. Then, SWAT model was used for discharge simulation of the Kratie, the main point of the Mekong River (watershed area: $646,000km^2$, 88% of the annual average flow rate of the Mekong River). As a result of the climate change analysis, the annual precipitation of the Kratie upper-watershed increase in both scenarios compared to the baseline yearly average precipitation. The monthly precipitation increase is relatively large from June to November. In particular, precipitation fluctuated greatly in the RCP 8.5 rather than RCP 4.5. Monthly average maximum and minimum temperature are predicted to be increased in both scenarios. As well as precipitation, the temperature increase in RCP 8.5 scenarios was found to be more significant than RCP 4.5. In addition, as a result of the duration curve comparison, the streamflow variation will become larger in low and high flow rate and the drought will be further intensified in the future.

• Journal of Korean Academy of Nursing
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• v.29 no.6
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• pp.1284-1293
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• 1999

This study was designed to investigate the effect of aromatherapy on skin xerosis and pruritus in patients undergoing maintenance hemodialysis. Twenty one subjects of this study were selected from St. Paul's Hosipital in Seoul. All the subjects were received the mineral oil massage at the arm without fistular three timesper week for 4 weeks. After 2 weeks period of wash-out, the subjects were received the aromatherapy of lavender and tea tree essence oil in the same way. This study was carried out from March 20 to June 13, 1998. Pruritus score, skin pH and stratum corneum hydration were measured before and after each treatment. But, biochemical parameters were measured before the treatment of the mineral oil massage, after the treatment of the mineral oil massage and the aromatherapy. Data of this study were analyzed by paired t-test, repeated measures ANOVA, Bonferroni multiple comparisons and Pearson correlation coefficient. The results were as follows ; 1. Pruritus score was significantly decreased after the aromatherapy, while no significant change after the treatment of the mineral oil massage. Therefore, there was a significant difference in the priritus score between the two treatments. 2. Stratum corneum hydration was significantly increased after the aromatherapy, while no significant change after the treatment of the mineral oil massage. Therefore, there was a significant difference in the stratum corneum hydration between the two treatments. 3. Skin pH was significantly increased after the treatment of the mineral oil massage, while no significant change after the aromatherapy. Therefore, there was no significant difference in the skin pH between the two treatments.4. After the aromatherapy, the serum calcium was significantly increased. Whereas the serum parathyroid hormone intact was significantly decreased compared with the treatment of the mineral oil massage. But the level of the serum Ca and PTH-intact were within the normal range. 5. Stratum corneum hydration was decreased corresponding to the duration of hemodialysis, while pruritus score and skin pH showed no change corresponding to the duration of hemodialysis and the age of the subjects. The correlation of pruritus score on skin pH, stratum corneum hydration and biochemical parameters was not significant. In conclusion, this findings indicate that aromatherapy may be effective in decreasing skin xerosis and pruritus score in uremic pruritus patients undergoing maintenance hemodialysis.

• Magazine of the Korean Society of Agricultural Engineers
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• v.41 no.5
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• pp.68-76
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• 1999

The purpose of the study was to investigated the change of hydraulic characteristics like water surface profile and rivered section in the down stream of Keum river after the construction of esturary dam. The effect of esturary dam on the flood control in the Keum river was recognized with the data of two flood events happened in July, 1987 before the construction and in August, 1995 after the construction of estuary dam. For example , duration time above the water level of the warning -flood was changed from 46.5 to 42.8 hours and duration time above the eater level of the danger-flood was changed from 24.7 to 19.8 hours at the Kyuam station. The time difference to reach the water level of the designated -flood between Kyuam and Kangkyung was changed from 3 hours in 1987 to 12 hours and 20 minutes in 1995. The water surface slope of river decreased 25.6% between estuary dam and Kangkyung and increased 16.5% between Kangkyung and Kyuam, and decreased 8.8% between Kyuam and Kongju. As the result, velocity was getting faster and river bed was scoured in the reach of Kangkyung and Kyuam, and velocity was getting slower and river bed was sedimented in the reach of Kangkyung and estury dam.

• Journal of the Korea Society of Computer and Information
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• v.18 no.2
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• pp.127-140
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• 2013

We explored the relationship between the level of change awareness and deployment of software process improvement (SPI) approaches using a competing values framework. To measure awareness level of organization's change, we used DICE framework provides means for predicting the outcome of change management initiatives. The four factors for organizaton's change: duration, integrity, commitment, and effort are evaluated and a score is calculated. The DICE(R) score is used to classify projects into win, worry, or woe zones. In this paper, we apply the DICE(R) score as an independent variable to predict the outcome of a software process improvement. Our results indicated that the Organization have a higher chance of success have the better outcome in software process improvement.