• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.1B
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• pp.47-62
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• 2009

The climate change caused by global warming may affect on the hydro-meteorologic factor such as evaporation (IPCC, 2001). Furthermore, it is also necessary that the effect of climate change according to geographical condition on evaporation should be studied. In this study, considering geographical and topographical conditions, the 6 evaporation equations that have been applied to simulate annual and monthly pan evaporation were compared. 56 climatologic stations were selected and classified, basing on the geographical and topographical characteristics (urbanization, topographical slope, proximity to coast, and area of water body). The evaporation equations currently being used are applied. These evaporation equations are Penman, Kohler-Nordenson-Fox (KNF), DeBruin-Keijman, Priestley-Taylor, Hargreaves, and Rohwer. Furthermore, Penman equation was modified by calibrating the parameters of wind function and was verified using relative error. The study results indicate that the KNF equation compared best with the pan: relative error was 8.72%. Penman equation provided the next-best values for evaporation relative to the pan: relative error was 8.75%. The mass-transfer method (Rohwer) provided the worst comparison showing relative error of 33.47%. In case that there is a close correlation between wind function and wind speed, modified Penman equation provided a better estimate of pan evaporation.

• ALGAE
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• v.26 no.2
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• pp.181-192
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• 2011

Ballasting and deballasting of shipping vessels in foreign ports have been reported worldwide as a vector of introduction of non-native aquatic plants and animals. Recently, attention has turned to ballast water as a factor in the global increase of harmful algal blooms (HABs). Many species of microalgae, including harmful dinoflagellate species, can remain viable for months in dormant benthic stages (cysts) in ballast sediments. Over a period of four years, we surveyed ballast water and sediment of ships docked in two ports of Tampa Bay, Florida, USA. Sampling conditions encountered while sampling ballast water and sediments were vastly different between vessels. Since no single sample collection protocol could be applied, existing methods for sampling ballast were modified and new methods created to reduce time and labor necessary for the collection of high-quality, qualitative samples. Five methods were refined or developed, including one that allowed for a directed intake of water and sediments. From 63 samples, 1,633 dinoflagellate cysts and cyst-like cells were recovered. A native, cyst-forming, harmful dinoflagellate, Alexandrium balechii (Steidinger) F. J. R. Taylor, was collected, isolated, and cultured from the same vessel six months apart, indicating that ships exchanging ballast water in Tampa Bay have the potential to transport HAB species to other ports with similar ecologies, exposing them to non-native, potentially toxic blooms.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.1
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• pp.46-51
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• 2004

The film coated snap bean (Phaseolus vulgaris) seeds with five different coating materials treated with 3% increase in seed weight were planted at sandy loam soil controlled moisture content of 18, 19, 20 and 21 %. The oxygen diffusion rate (ODR) was calculated from the different moisture content soil. The number of normal seedlings, seedling vigor, and seedling capability in field (seed vigor x dry matter weight) were observed at 9 days after planting and compared to the changes of ODR. The germination rate and ODR were sharply decreased simultaneously in the seeds planted at 21 % soil moisture content. Seedling emergence did not occur at all as the soil moisture content increased above 22 %. Hence this value should be considered as the threshold of soil moisture content for seedling emergence. An ODR value under 20% did not influence the percent emergence significantly. The certain difference observing in the emergence at the same ODR was not related clearly to the condition of soil. So it can be assumed that the limit of soil moisture content for the emergence of snap bean was approximately 20%. The value of 18% soil moisture content may be considered as the optimum for snap bean emergence. There was close relationship between the mean value of ODR in different soil moisture contents and the emergence. The germination rates of the seeds coated with the different materials were quite different when the seeds were planted at 21 % soil moisture. Dry weight of the seedlings from film coated seeds was decreased slightly, but the germination rates were not much different from the non-treated control under relatively higher soil moisture content (21 %). Major factor lowering emergence rate was oxygen stress while film coating act as a minor constraint for snap bean sown in excess soil moisture condition.

• Structural Engineering and Mechanics
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• v.56 no.6
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• pp.959-982
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• 2015

In this study, a non-stationary random earthquake Clough-Penzien model is used to describe earthquake ground motion. Using stochastic direct integration in combination with an equivalent linear method, a solution is established to describe the non-stationary response of lead-rubber bearing (LRB) system to a stochastic earthquake. Two parameters are used to develop an optimization method for bearing design: the post-yielding stiffness and the normalized yield strength of the isolation bearing. Using the minimization of the maximum energy response level of the upper structure subjected to an earthquake as an objective function, and with the constraints that the bearing failure probability is no more than 5% and the second shape factor of the bearing is less than 5, a calculation method for the two optimal design parameters is presented. In this optimization process, the radial basis function (RBF) response surface was applied, instead of the implicit objective function and constraints, and a sequential quadratic programming (SQP) algorithm was used to solve the optimization problems. By considering the uncertainties of the structural parameters and seismic ground motion input parameters for the optimization of the bearing design, convex set models (such as the interval model and ellipsoidal model) are used to describe the uncertainty parameters. Subsequently, the optimal bearing design parameters were expanded at their median values into first-order Taylor series expansions, and then, the Lagrange multipliers method was used to determine the upper and lower boundaries of the parameters. Moreover, using a calculation example, the impacts of site soil parameters, such as input peak ground acceleration, bearing diameter and rubber shore hardness on the optimization parameters, are investigated.

• Journal of Gynecologic Oncology
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• v.29 no.6
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• pp.97.1-97.12
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• 2018

Objective: Women with cervical cancer (CC) found to have positive surgical margins, positive lymph nodes, and/or parametrial invasion receive a survival benefit from postoperative chemoradiotherapy (CRT) vs. radiation therapy (RT) alone. However, older women may not benefit to the same extent, as they are at increased risk of death from non-oncologic causes as well as toxicities from oncologic treatments. This study sought to evaluate whether there was a survival benefit of CRT over RT in elderly patients with cervical cancer. Methods: The National Cancer Database was queried for patients ${\geq}70$ years old with newly diagnosed IA2, IB, or IIA CC and positive margins, parametrial invasion, and/or positive nodes on surgical resection. Statistics included logistic regression, Kaplan-Meier overall survival (OS), and Cox proportional hazards modeling analyses. Results: Altogether, 166 patients met inclusion criteria; 62 (37%) underwent postoperative RT and 104 (63%) underwent postoperative CRT. Younger patients and those living in areas of higher income were less likely to receive CRT, while parametrial invasion and nodal involvement were associated with an increased likelihood (p<0.05 for all). There were no OS differences by treatment type. Subgroup analysis by number of risk factors, as well as each of the 3 risk factors separately, also did not reveal any OS differences between cohorts. Conclusion: In the largest such study to date, older women with postoperative risk factor(s) receiving RT alone experienced similar survival as those undergoing CRT. Although causation is not implied, careful patient selection is paramount to balance treatment-related toxicity risks with theoretical outcome benefits.

• Journal of the Korean GEO-environmental Society
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• v.15 no.7
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• pp.59-66
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• 2014

Nowadays, some studies are performed in order to introduce the Limit State Design method widely used in foreign work sites. LRFD (Load Resistance Factor Design) method is widely used in the fields in which the data accumulation is possible - such as deep foundations, and shallow foundations, etc. The limit state design in the retaining walls is insufficient in the country owing to difficulties applying load tests. The limit state design method for retaining wall structures are studied based upon the National Retaining wall Design Standard legislated in 2008 by Ministry of Land, Transport, and Maritime Affairs. In this paper several retaining walls were calculated according to LRFD design criteria analysis using the general program with limit state design method and the factor of safety for sliding and overturning. Comparing with their results, the Taylor's series simple reliability analysis was performed. In the analysis results of retaining wall section, safety factors calculated by LRFD were found to be lowered than those calculated in current WSD, and it is possibly judged to be economic design by changing wall dimensions. In the future, pre-assessment of the geotechnical data for ensuring the reliability and the studies including reinforced retaining walls with ground anchor are needed.

• Journal of Korea Port Economic Association
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• v.25 no.1
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• pp.107-124
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• 2009

In order to create value for maritime tourism industry, new port infrastructures have been planned, improvements in passenger terminal services have been designed, and new maritime transport technologies have been applied, so that ports improve their efficiency and the quality of their service more than their national and international competitors. Thus, the purpose of this study is to verify the dimensions of the service quality of ocean passenger terminal. Based on a survey of 260 customers in port of Busan and Inchon, terminal service quality's five main dimensions have been checked regarding their fit with the use of Confirmatory Factor Analysis. Empirical results support that this is a valid instrument for measuring service quality of a ocean passenger terminal. The interactive sequence of computing Cronbach's alpha, corrected item-to-total correlation, and factor analysis was repeated a few times and resulted in a final set of 19 items representing five distinct dimensions-tangibles, responsiveness, knowledge, reliability, and accessibility. This finding provides the more appropriate instrument to evaluate the customers perception as well as to measure the service quality of ocean passenger terminal.

• Korean Journal of Psychosomatic Medicine
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• v.11 no.1
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• pp.77-88
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• 2003

Objectives: The purpose of this study was to compare reliability and validity of three Korean versions of the 20-item Toronto Alexithymia scale and to confirm the most reliable and validated Korean translation of the 20-item Toronto Alexithymia Scale for both clinical and research purpose in Korea. The first one was a Korean version of the 20-Item Toronto Alexithymia Scale developed by Lee YH et al in 1996 which was designated as TAS-20K(1996) in this study. This scale had a problem with one item due to the cultural difference regarding the word 'analyzing' between western culture and Korean culture. The second one was the revised version of TAS-20K(1996) on that point by Lee YH et al in 1996 without validation which was designated as TAS-20K(2003) in this study. The third one was a 23-item Korean version developed by Sin HG and Won HT in 1997, which was somewhat different from the 20-item Toronto Alexithymia Scale(TAS-20) in the number of total item, the content of some items and the scoring method. This scale was designated as S-TAS here. Methods: 408 medical students were tested with one scale composed of all the different items randomly arranged from the three versions. We evaluated goodness-of-fit and Cronbach $\alpha$ coefficients of three scales for reliability. We used confirmatory factor analysis to compare validity. Results: TAS-20K(2003) showed that it had better internal consistency than TAS-20K(1996), which implied that the cultural difference should be considered in the Korean translation. Both TAS-20K(2003) and S-TAS replicated three-factor structures and had adequacy of fit, good internal consistency and acceptable validity. However, S-TAS had one item with poor item-factor correlation and didn't show high correlation between item 2 and factor 1 as before in 1997. Conclusion: Although S-TAS had added 3 items and changed the content of two items, it didn't show better reliability and validity than TAS-20K(2003). Therefore it is proposed to use TAS-20K (2003) as the Korean version of the 20-item Toronto Alexithymia Scale(TAS-20K) for international communication of results of Alexithymia research. It has good internal consistency and validity and maintains original items, the same construct and scoring method as the 20-item Toronto Alexithymia Scale.

• The Journal of the Acoustical Society of Korea
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• v.16 no.5
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• pp.112-121
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• 1997

In this paper, we study a model parameter compensation method for noise-robust speech recognition. We study model parameter compensation on a sentence by sentence and no other informations are used. Parallel model combination(PMC), well known as a model parameter compensation algorithm, is implemented and used for a reference of performance comparision. We also propose a modified PMC method which tunes model parameter with an association factor that controls average variability of gaussian mixtures and variability of single gaussian mixture per state for more robust modeling. We obtain a re-estimation solution of environmental variables based on the expectation-maximization(EM) algorithm in the cepstral domain. To evaluate the performance of the model compensation methods, we perform experiments on speaker-independent isolated word recognition. Noise sources used are white gaussian and driving car noise. To get corrupted speech we added noise to clean speech at various signal-to-noise ratio(SNR). We use noise mean and variance modeled by 3 frame noise data. Experimental result of the VTS approach is superior to other methods. The scheme of the zero order VTS approach is similar to the modified PMC method in adapting mean vector only. But, the recognition rate of the Zero order VTS approach is higher than PMC and modified PMC method based on log-normal approximation.

• Journal of Korea Water Resources Association
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• v.44 no.12
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• pp.915-928
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• 2011

The main purpose of this study is to understand the effects of hydroclimatic factors on annual actual evapotranspiration and to suggest the multiple linear regression (MLR) equations for the estimation of annual actual evapotranspiration from watershed. To accomplish this study purpose, 5 dam watersheds (Goesan dam, Seomjingang dam, Soyanggang dam, Andong dam, Hapcheon dam) were selected as study watersheds and annual actual evapotranspiration was estimated based on annual water balance analysis from each watershed. The estimated annual actual evapotranspiration from water balance analysis was used to evaluate the MLR equations. Furthermore, the possibility of the estimation of actual evapotranspiration using potential evapotranspiration equations (Penman equation, FAO P-M equation, Makkink equation, Preistley-Taylor equation, Hargreaves equation) was evaluated. It has turned out that it is not appropriate to use potential evapotranspiration for the estimation of actual evapotranspiration because the correlation between actual evapotranspiration and potential evapotranspiration is very low. The comparison of MLR equations with current actual evapotranspiration equations indicates that MLR equations can be used for the estimation of annual actual evapotranspiration. Furthermore, it has turned out that the effects of hydroclimatic factors on annual actual evapotranspiration from dam watersheds are different in each watershed; however, for all watersheds in common precipitation has turned out to be the most important climatic factor affecting on the estimation of annual actual evapotranspiration.