• 대한조선학회지
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• 제25권1호
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• pp.3-10
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• 1988

This paper presents some experimental investigations on the effectiveness of the Stern-End-Bulb(SEB) and the design procedure of the optimum one. Experimental method was discussed to search the optimum SEB and the resistance reduction rate was investigated from the resistance test results of the SEB series for a passenger boat and a container ship. The contribution of SEB on the propulsive coefficients was discussed from the self-propulsion test results for a container ship. It would be expected that the power saving rate is about 5.8 percents for a passenger boat and 3.6 percents for a container ship by optimum SEB, respectively.

• 반도체디스플레이기술학회지
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• 제7권2호
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• pp.35-38
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• 2008

This study shows the improvement of PR-Ashing rates in semi-conductor process using Atmospheric Plasma. Taguchi method is used to improve Ashing rates of photo-resist that is spread on the surface of a wafer. Improvement of Ashing rates is acquired through the decision of the effective factors and suitable combination of the factors. The results show the contribution rate of each factor and the effectiveness of Plasma for PR-Ashing process in this system.

• 한국멀티미디어학회논문지
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• 제19권8호
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• pp.1404-1414
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• 2016

Cross-layer design is a concept, which captures the dependencies and interactions and enables information sharing among layers in order to improve the network performance and security. There are two key challenges in wireless networks, lossy features of links and power assumption of network nodes. Cross-layer design of congestion control and power allocation in wireless lossy networks has been studied in the existing literature; however, there has been no contribution proposed in the literature that exploits the path diversity. In this paper, we are motivated to develop a cross-layer design of congestion control and power allocation, which takes into account lossy features of wireless links and transmission powers of network nodes and can be implemented in a distributed manner. Numerical simulation is conducted to illustrate the performance of our proposed algorithm and the comparison with current alternative approaches.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.726-729
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• 2004

Etching characteristics of (Pb,Sr)$TiO_3$(PST) thin films were investigated using inductively coupled chlorine based plasma system as functions of gas mixing ratio, RF power and DC bias voltage. It was found that increasing of hi content in gas mixture lead to sufficient increasing of etch rate and selectivity of PST to Pt. The maximum etch rate of PST film is $562{\AA}/min$ and the selectivity of PST film to Pt is 0.8 at $Cl_2/(Cl_2+Ar)$ of 20 %. It was Proposed that sputter etching is dominant etching mechanism while the contribution of chemical reaction is relatively low due to low volatility of etching products.

• 한국작물학회지
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• 제52권1호
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• pp.112-121
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• 2007

Grain filling is a crucial factor that determines grain yield in crops since it is the final process directly associated with crops' yield performance. Grain filling process can be characterized by the interaction of rate and duration of grain filling. This study was conducted, using 16 temperate japonica rice genotypes, with aims to (1) seek variations in grain filling duration and rate on area basis, (2) compare the contribution of grain filling duration and rate to grain yield, and (3) examine the influence of temperature and solar radiation for effective grain filling on grain yield in relation to grain filling duration and rate. Grain filling rate and duration exhibited highly significant variations in the ranges of $20.7{\sim}46.3\;g\;m^{-2}d^{-1}\;and\;11.2{\sim}35.5$ days, respectively, depending on rice genotypes. Grain yield on unit area basis was associated positively with grain filling duration but negatively with grain filling rate. Grain filling rate and duration were negatively correlated with each other. Final grain weight increased linearly with the rise in both cumulative mean temperature and cumulative solar radiation for effective grain filling. Higher cumulative mean temperature and cumulative solar radiation for effective grain filling were the results of longer grain filling duration, but not necessarily higher daily mean temperature and daily solar radiation for effective grain filling. Grain filling rate demonstrated an increasing tendency with the rise in daily mean temperature for effective grain filling but their relationship was not obviously clear. It was concluded that grain filling duration, which influenced cumulative mean temperature and cumulative solar radiation for effective grain filling, was the main factor that determined grain yield on unit area basis in temperate Japonica rice.

• Geomechanics and Engineering
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• 제36권2호
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• pp.111-119
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• 2024

In the realm of rock excavation projects, precise estimation of the drilling rate index stands as a pivotal factor in strategic planning and cost assessment. This study introduces and evaluates two pioneering computational intelligence models designed for the prognostication of the drilling rate index, a pivotal parameter with direct implications for cost estimation in rock excavation projects. These models, denoted as the Relevance Vector Regression (RVR) optimized with the Invasive Weed Optimization algorithm (IWO) (RVR-IWO model) and the RVR integrated with the Shuffled Frog Leaping algorithm (SFL) (RVR-SFL model), represent a groundbreaking approach to forecasting drilling rate index. The RVR-IWO and RVR-SFL models were meticulously devised to harness the capabilities of computational intelligence and optimization techniques for drilling rate index estimation. This research pioneers the integration of IWO and SFL with RVR, constituting an unprecedented effort in forecasting drilling rate index. The primary objective of this study was to gauge the precision and dependability of these models in forecasting the drilling rate index, revealing significant distinctions between the two. In terms of predictive precision, the RVR-IWO model emerged as the superior choice when compared to the RVR-SFL model, underscoring the remarkable efficacy of the Invasive Weed Optimization algorithm. The RVR-IWO model delivered noteworthy results, boasting a Variance Account for (VAF) of 0.8406, a Mean Squared Error (MSE) of 0.0114, and a Squared Correlation Coefficient (R²) of 0.9315. On the contrary, the RVR-SFL model exhibited slightly lower precision, yielding an MSE of 0.0160, a VAF of 0.8205, and an R2 of 0.9120. These findings serve to highlight the potential of the RVR-IWO model as a formidable instrument for drilling rate index prediction, particularly within the framework of rock excavation projects. This research not only makes a significant contribution to the realm of drilling engineering but also underscores the broader adaptability of the RVR-IWO model in tackling an array of challenges within the domain of rock engineering. Ultimately, this study advances the comprehension of drilling rate index estimation and imparts valuable insights into the practical implementation of computational intelligence methodologies within the realm of engineering projects.

• 한국의류학회지
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• 제24권3호
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• pp.301-312
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• 2000

This study conducted an analysis of the middle aged women whose ages are from 35 to 59 years old in order to give those ladies much external satisfaction and covered body lines. I have come to present a few characters of body types as silhouettes which resulted in the factors of the upper bodies of middle aged women. I have adopted SAS(statistical analysis system) as a data process method of this survey. The followings are the results analysis. 1. The item of height have decreased, but increased in the items of thickness among the late middle aged women. 2. The body componant factor of middle aged women are extracted as 10 items, and the rate of their cumulative contribution is 78.9%. The first is the thickness of upper body, the second is the thickness of side upper body, the third is the height of upper body, the fourth is the length of upper body the fifth is width of upper body, the sixth is the projected rate of back, the seventh is the projected rate of breast, the eighth is the squared rate of shoulder, the ninth is the crooked rate of neck, and the tenth is the upper from of breast. 3. The body types of middle aged women can be classified into 4 types, and the followings are their characters. Type 1 is a standard type as the most common body character of the middle aged women, showing the appearing rate of 42.4%. Type 2 is a semi-curved body type like the curved figure of side body, showing the appearing rate of 34.5%. Type 3 is a reverse body type with the projected breast feature of front body, showing the appearing rate of 20.9%. Type 4 is a crooked body type with a tall height and crooked neck, showing the appearing rate of 2.2%.

• 한국환경농학회지
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• 제30권2호
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• pp.99-104
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• 2011

BACKGROUND: Application of urea may increase $CO_2$ emission from soils due both to $CO_2$ generation from urea hydrolysis and fertilizer-induced decomposition of soil organic carbon (SOC). The objective of this study was to investigate the effects of increasing urea application on $CO_2$ emission from soil and mineralization kinetics of indigenous SOC. METHODS AND RESULTS: Emission of $CO_2$ from a soil amended with four different rates (0, 175, 350, and 700 mg N/kg soil) of urea was investigated in a laboratory incubation experiment for 110 days. Cumulative $CO_2$ emission ($C_{cum}$) was linearly increased with urea application rate due primarily to the contribution of urea-C through hydrolysis to total $CO_2$ emission. First-order kinetics parameters ($C_0$, mineralizable SOC pool size; k, mineralization rate) became greater with increasing urea application rate; $C_0$ increased from 665.1 to 780.3 mg C/kg and k from 0.024 to 0.069 $day^{-1}$, determinately showing fertilizer-induced SOC mineralization. The relationship of $C_0$ (non-linear) and k (linear) with urea-N application rate revealed different responses of $C_0$ and k to increasing rate of fertilizer N. CONCLUSION(s): The relationship of mineralizable SOC pool size and mineralization rate with urea-N application rate suggested that increasing N fertilization may accelerate decomposition of readily decomposable SOC; however, it may not always stimulate decomposition of non-readily decomposable SOC that is protected from microbial decomposition.

• 보건행정학회지
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• 제31권1호
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• pp.35-45
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• 2021

Background: As a descriptive study targeting 2,068 cancer patients as men of national merit in 2013, this study aims to provide the basic data for systematizing the early diagnosis and treatment of cancer by comparatively analyzing the 5-year survival rate. Methods: This study researched the survival of cancer patients through Electronic Medical Record and Patriots-Veterans Qualification Program, targeting 2,068 newly-diagnosed cancer patients verified in five veterans hospitals and consigned management system. This study verified differences between general characteristics of cancer patients as men of national merit and analyzed their survival rate. Results: The cancer patients as men of national merit were super-aged as their average age was 72.5. In the analysis of general characteristics of five major prevalent cancers, there were statistically significant differences according to age, region, cancer diagnostic path, differentiation, diagnostic method, treatment method, SEER stage, and survival period, except for the types of the man of national merit (p<0.001). The whole survival rate of cancer patients as men of national merit was 50%. The 5-year survival rates of predisposing cancers were shown as prostate cancer (79%), colorectal cancer (64%), gastric cancer (57%), liver cancer (32%), and lung cancer (12%). In the cancer diagnostic path, all the predisposing cancers showed the highest survival rate in medical examination. In the treatment method, the surgery showed the highest survival rate. The cancer patients as men of national merit showed a lower survival rate than the general cancer patients of Korea. Conclusion: It would be needed to guarantee the honorable and happy life through health recovery as special treatment of contribution and sacrifice of super-aged men of national merit by increasing the cancer survival rates through regular checkup, early diagnosis, and high-quality treatment system that could have important effects on the survival rate according to the occurrence of cancers.

• 보건행정학회지
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• 제19권3호
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• pp.92-108
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• 2009

This study suggests a model for continuing and comprehensive management of hypertension or Type 2 diabetes mellitus (T2DM) in Korea. Moreover, this paper computed the contribution cost of hypertension or T2DM management using the healthcare medical cost, which could have occurred from stroke, myocardial infarction (MI), and end-stage renal disease (ESRD) that were successfully prevented from the effective hypertension or T2DM management. Additionally, these costs were compared with the cost of implementing the hypertension or T2DM management model suggested in this study. This study used the medical fee summary of the health insurance claims submitted to National Health Insurance Corporation by medical facilities for services provided during the period from January 1st 1999 to December 31st 2006. The prevalence rate with treatment referred to cases in which patients submitted their medical claims at least once during the period, along with an accordant diagnosis. The incidence rate with treatment referred to cases in which patients who never submitted claims for the accordant disease during the five years from 1999 to 2003 submitted claims for the accordant disease in 2004 and 2005. The relative risk of the occurrence of stroke, MI and ESRD was 11.0, 13.6, and 30.3, respectively. The attributable risk of hypertension or T2DM for stroke was 0.730, and that for MI and ESRD were 0.773 and 0.888, respectively. Based on these, the contribution cost of hypertension or T2DM is estimated to be 986.3 billion Korean Won(KRW) for stroke patients, 330.5 billion KRW for MI patients, and 561.7 billion KRW for ESRD patients as in 2005. Hence, the total contribution cost of hypertension or T2DM to stroke, MI, and ESRD is 1.878 trillion KRW. The estimate for operational costs included an annual expenditure of 50,000 KRW per each recipient and an annual subsidy of 0.22 million KRW per person for the 1.6 million low.income individuals with hypertension or T2DM to cover their out.of.pocket medical expenses. Under this assumption, it took approximately 0.6 trillion KRW to manage 5 million high.risk patients in the low. and mid.income range, coverings up to 50% of costs. In conclusion, considering the potential benefits of preventing stroke, MI, and ESRD, the costs seems to be reasonable.