• Korean Journal of Ecology and Environment
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• v.40 no.1
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• pp.50-60
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• 2007

Ten taxa of green algae collected at 8 stations of reservoirs and one of aerial habitat were reported newly in Korea. They belong to 7 genera, 2 species, 6 varieties and 2 forms and include one taxon of Scenedesmus, Actinotaenium, Euastrum, Hyalotheca, Staurastrum and Teilingia respectively, 4 taxa of Cosmarium. The Korean green algae, including these newly reported ones, totals to 1,131 taxa, and classified as 1 class, 10 orders, 34 families, 140 genera, 728 species, 318 varieties and 85 forms. Actinotaenium cucurbita var. cucurbita f. rotundatum cultured in this study was appeared to be variable in the size of isthmus. In the Korean taxa of Cosmarium lapponicum var. granulatum, C. portianum var. orthostichum and Euastrum denticulatum var. rectangulare, cell sizes were shown smaller than previously reported ones. Five taxa including Cosmarium lapponicum var. granulatum were occurred in the eutrophic states, and Cosmarium decedens, previously reported as present in the freshwater area, was collected at the aerial habitat in this study.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.26 no.5
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• pp.513-518
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• 2008

The research of global-scale mass redistribution and it changed by Earth gravity filed variation observations, including Earth's oblateness $J_2$(also called low degree spherical harmonic coefficient $C_{20}$), is in continuous progress. Recently, the comparative analysis of geodetic observation SLR can be made by the development of GRACE and other time-variable gravity measurements. In this study, $C_{20}$ time series changes in the value of comparative analysis was got by GRACE monthly Gravity filed model (CSR RL04) for the period April 2002 to May 2008. And comparative analysis the harmonic coefficients of $C_{20}$ was obtained from SLR observations. Signal analysis for two time-series data was made by wavelet transform, CWT(continuous wavelet transform), XWT(cross wavelet transform) and WTC(wavelet coherence) methods. The results indicate that GRACE and SLR values for $C_{20}$ had both decreasing trend, as well as SLR data represent the annual frequencies, and GRACE was semiannual variations. In addition, the results of GRACE and SLR had a strong correlation with the XWT and WTC in an annual cycle.

• Journal of Korea Water Resources Association
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• v.45 no.11
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• pp.1131-1141
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• 2012

In this study, factors that influence water supply capacities of dams are extracted using factor analysis, and multiple regression equations for estimating water supply capacities of dams are developed using the analysis results. Twenty-one multi-purpose dams and twelve Municipal and Industrial (M&I) water supply dams are selected for case studies, and eight variables influencing water supply capacities of dams, namely: watershed area, inflow, effective reservoir storage, grade on amount of M&I water supply, grade on amount of agricultural water supply, grade on amount of in-stream flow supply, grade on river administration, and grade on average rainfall, are determined. Two case studies for multi-purpose dams and M&I water supply dams are performed, employing factor analysis, respectively. For the two cases, preliminary tests, such as reviewing matrix of correlation coefficient, Bartlett's test of sphericity, and Kaiser-Meyer-Olkin (KMO) test, are conducted to evaluate the suitability of the variables for factor analysis. In case of multi-purpose dams, variables are grouped into three factors; M&I water supply dams, two factors. The factors are rotated using Varimax method, and then factor loading of each variable is computed. The results show that the variables influencing water supply capacities of dams are reasonably selected and appropriately grouped into factors. In addition, multiple regression equations for predicting the amounts of annual water supply of dams are established using the factor scores as explanatory variables, it is identified that the models' accuracies are high, and their applications to determining effective storage capacity of a dam during dam planning and design steps are presented. Consequently, it is thought that the variables and factors are useful for dam planning and dam design.

• Journal of the Korea Furniture Society
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• v.21 no.6
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• pp.439-448
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• 2010

Furniture world which is closely associated with human life had been constantly developed, but traditional furniture disappeared after modernization almost. The reason lies rather in the importance of the diversity of Western-style furniture pursuing convenience and shapes, than in change of life style meanwhile. The diversity however reached the limit and it made a new advanced role of not only furniture, also design sector in general necessary, and as solution to solve this problem the immaterial value based on Eastern philosophy/mental was suggested in architecture and all around design sector overall as well. It means that the immaterial point which traditional furniture involved should be focused now and furthermore it's emotional and mental value which is more natural and has close relation with human being accordingly could be judged rightly. The reason why traditional furniture had been used since long time is the immaterial tendency which is well harmonized with the surrounding environment rather than the function. To verify this, the present study aimed to analyze not only the basic, also additional function of traditional furniture used in Hanok (traditional Koran-style house) by the inductive method for investigating the additional effects which users felt. Such immaterial role offers the user more convenience besides the original function of furniture and this made it available that furniture dominates the space. As good examples of such roles it was investigated that traditional furniture played meaningful roles like extensional serviceability, variable space, formation & movement of space, expression of grade of rank. That allowed that this study suggested the sustainable design and also the direction of development of interactive function of furniture through the expected effect having been showed in the modern space where the immaterial role of traditional furniture was applied to and the related cases.

• Economic and Environmental Geology
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• v.28 no.3
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• pp.199-211
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• 1995

The deep sea camera system could render it possible to obtain the detailed information of the nodule distribution, but difficult to estimate nodule abundance quantitatively. In order to estimate nodule abundance quantitatively from deep seabed photographs, the nodule abundance equation was derived from the box core data obtained in KODOS area(long.: $154^{\circ}{\sim}151^{\circ}W$, lat.: $9^{\circ}{\sim}12^{\circ}N$) during two survey cruises carried out in 1989 and 1990. The regression equation derived by considering extent of burial of nodule to Handa's equation compensates for the abundance error attributable to partial burial of some nodules by sediments. An average long axis and average extent of burial of nodules in photographed area are determined according to the surface textures of nodules, and nodule coverage is calculated by the image analysis method. Average nodule abundance estimated from seabed photographs by using the equation is approximately 92% of the actual average abundance in KODOS area. The measured sampling points by box core or free fall grab are in general very sparse and hence nodule abundance distribution should be interpolated and extrapolated from measured data to uncharacterized areas. The another goal of this study is to depict continuous distribution of nodule abundance in KODOS area by using PC-version of geostatistical model in which several stages are systematically proceeded. Geostatistics was used to analyse spatial structure and distribution of regionalized variable(nodule abundance) within sets of real data. In order to investigate the spatial structure of nodule abundance in KODOS area, experimental variograms were calculated and fitted to a spherical models in isotropy and anisotropy, respectively. The spherical structure models were used to map out distribution of the nodule abundance for isotropic and anisotropic models by using the kriging method. The result from anisotropic model is much more reliable than one of isotropic model. Distribution map of nodule abundance produced by PC-version of geostatistical model indicates that approximately 40% of KODOS area is considered to be promising area(nodule abundance > $5kg/m^2$) for mining in case of anisotropy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.12
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• pp.5843-5848
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• 2011

To improve the efficiency of the channel spectrum and to reduce the power consumption of the system in EVRC, the voice signal is compressed and transmitted only when the user speaks to. In addition to this, voice frames are divided into three rates 1, 1/2 and 1/8 and each frame is handled differently. For example, we assumed that the input is silence region if the 1/8 rate is used. In this paper, the sections are firstly separated into the voiced speech signal region, unvoiced speech signal region, and silence region by using distribution characteristics of LSP parameters. Then the paper suggested to encode 1 rate for the voiced speech signal, 1/2 rate for the unvoiced speech signal region, 1/8 rate for the silence region. In other words, traditional way of transmission is used when sending full rate in the EVRC. However, when sending half rate, the voice is firstly distinguished between voiced and unvoiced. If the voice is distinguished as voiced, voice is converted into full rate before the transmission. If it is distinguished as silence, EVRC's basic rate is applied. In the experimental results with SNR, ASDM, transmission bit rate measurement, we have demonstrated that voice quality was improved by using the proposed algorithm.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.2
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• pp.799-805
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• 2016

Background: There is no standard treatment for patients with platinum-resistant or refractory epithelial ovarian cancer. Single agent chemotherapies have evidence of more efficacy and less toxicity than combination therapy. Most are very expensive, with appreciable toxicity and minimal survival. Since it is difficult to make comparison between outcomes, economic analysis of single-agent chemotherapy regimens and best supportive care may help to make decisions about an appropriate management for the affected patients. Objective: To evaluate the cost effectiveness of second-line chemotherapy compared with best supportive care for patients with platinum-resistant or refractory epithelial ovarian cancer. Materials and Methods: A Markov model was used to estimate the effectiveness and total costs associated with treatments. The hypothetical patient population comprised women aged 55 with platinum-resistant or refractory epithelial ovarian cancer. Four types of alternative treatment options were evaluated: 1) gemcitabine followed by BSC; 2) pegylated liposomal doxorubicin (PLD) followed by BSC; 3) gemcitabine followed by topotecan; and 4) PLD followed by topotecan. Baseline comparator of alternative treatments was BSC. Time horizon of the analysis was 2 years. Health care provider perspective and 3% discount rate were used to determine the costs of medical treatment in this study. Quality-adjusted life-years (QALY) were used to measure the treatment effectiveness. Treatment effectiveness data were derived from the literature. Costs were calculated from unit cost treatment of epithelial ovarian cancer patients at various stages of disease in King Chulalongkorn Memorial Hospital (KCMH) in the year 2011. Parameter uncertainty was tested in probabilistic sensitivity analysis by using Monte Carlo simulation. One-way sensitivity analysis was used to explore each variable's impact on the uncertainty of the results. Results: Approximated life expectancy of best supportive care was 0.182 years and its total cost was 26,862 Baht. All four alternative treatments increased life expectancy. Life expectancy of gemcitabine followed by BSC, PLD followed by BSC, gemcitabine followed by topotecan and PLD followed by topotecan was 0.510, 0.513, 0.566, and 0.570 years, respectively. The total cost of gemcitabine followed by BSC, PLD followed by BSC, gemcitabine followed by topotecan and PLD followed by topotecan was 113,000, 124,302, 139,788 and 151,135 Baht, respectively. PLD followed by topotecan had the highest expected quality-adjusted life-years but was the most expensive of all the above strategies. The incremental cost-effectiveness ratios (ICER) of gemcitabine followed by BSC, PLD followed by BSC, gemcitabine followed by topotecan and PLD followed by topotecan was 344,643, 385,322, 385,856, and 420,299 Baht, respectively. Conclusions: All of the second-line chemotherapy strategies showed certain benefits due to an increased life-year gained compared with best supportive care. Moreover, gemcitabine as second-line chemotherapy followed by best supportive care in progressive disease case was likely to be more effective strategy with less cost from health care provider perspective. Gemcitabine was the most cost-effective treatment among all four alternative treatments. ICER is only an economic factor. Treatment decisions should be based on the patient benefit.

• The Journal of the Korea Contents Association
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• v.16 no.5
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• pp.229-241
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• 2016

This research has its purpose to seek, among the CEOs of social enterprises, the influence of job stress on business performance, social support inbetween them, and adjusting role of government-supported policies. CEO of social enterprise, which is established to realize its social purposes, receives the job stress due to business ethics, profitability, identity crisis, management challenges and etc. We would like to set the foundation for the enterprises to constantly conduct social purposes within the local society by raising the business performances of social enterprises through seeking the measures to resolve such job stresses of the CEOs by expressing them. This research applied the ISR Job Stress Model theroy as its main ground of theoretical background. We would like to analyze the inter-significance by setting the job stress causes and job stress influences as independent variables, business achievements as a dependent variable, and social support, government-supported policies as moderating variables. For the methods of the research, we collected, using structuralized questionnaire, from 223 social enterprise CEOs located within Korea. Data analysis used IBM SPSS Statristics 20.0 programme, and through general characteristic of sample, confidence testing, factorial analysis, correlation analysis and research hypothesis testing, drew the following results. First, job stress factor and influence were analyzed to have negative impacts on business performance. Second, social support was found to lower job stress factor and influence, and raise business performance. Third, government-supported policy was analyzed to lower job stress factor and influence, and raise business performance.

• Journal of the Korean Society for Marine Environment & Energy
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• v.4 no.4
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• pp.12-20
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• 2001

The temporal variability in near-field mixing characteristics of discharging plumes in oceanic environment was investigated using the time series data of the buoyant jet parameters. Based on the currents and density profiles observed in Masan outfall site and effluent discharge flowrates for 63days of summer season, the temporal variabilities and those occurrence frequency were obtained by line plume equations. The results show that wide range of variability in Masan outfall's mixing characteristics was found due to the temporal changes of effluent flowrates and ambient oceanic conditions. The near-field dilution was in the range of 30~71 with the averaged dilution of 34, which was a good agreement with field measurements of salinity deficit. The length of mixing zone was in the range of 5.4~36.2 m with the average of 9.5 m, and the plume rise height was in the range of 8.1~10.2 m with the average of 8.9 m. However, only the 30~44% of the whole results are higher than the averages, which indicates the necessity of this frequency analysis with the continuously measured data for designing and managing the ocean outfall system.

• Journal of Korea Technology Innovation Society
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• v.10 no.1
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• pp.164-181
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• 2007

This paper empirically analyzes determinants of DTV (Digital Television) adoption in household survey data with IT-related household demand characteristics. To this purpose, we conducted a survey for the adoption of DTV to 1,000 households nationwide. In the questionnaire, various questions asking socio-economics characteristics such as age, education, income were included. Also, status of adoption and usage of IT services such as paid broadcasting, internet, and DVD were asked. To analyze the determinants of intention of purchasing, decision of purchasing, and the timing of purchasing DTV, we adopted the ordered logit, binary logit and multinomial legit models. When there is an order among groups, ordered logit was employed and when there is no orders among groups, multinomial logit was emplyed for the estimation. It is found that when conditions of other explanatory variable are constant, the more educated household heads are, the more probable they become early adopters of DTV. It is also found that other conditions being constant, the income level of households and IT-related household demand characteristics are very important factors affecting DTV adoption. Since the likelihood of purchasing DTV is much higher for those who know the government policy of analog broadcasting termination schedule than others who do not know, dissemination of the Korean government's digital broadcasting policy will affect significantly the adoption of DTV. And policy with various incentives ought to be employed to accelerate DTV adoption, because households with the older TV sets are more likely to purchase DTV. It is suggested that the Korean government should develop policy to connect both DBS (Direct Broadcast Satellite) and DTV since DBS subscribers are more likely to be an early adopter than non-subscribers.