• Journal of Intelligence and Information Systems
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• v.18 no.4
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• pp.43-57
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• 2012

To enhance the competitive advantage in a constantly changing business environment, an enterprise management must make the right decision in many business activities based on both internal and external information. Thus, providing accurate information plays a prominent role in management's decision making. Intuitively, historical data can provide a feasible estimate through the forecasting models. Therefore, if the service department can estimate the service quantity for the next period, the service department can then effectively control the inventory of service related resources such as human, parts, and other facilities. In addition, the production department can make load map for improving its product quality. Therefore, obtaining an accurate service forecast most likely appears to be critical to manufacturing companies. Numerous investigations addressing this problem have generally employed statistical methods, such as regression or autoregressive and moving average simulation. However, these methods are only efficient for data with are seasonal or cyclical. If the data are influenced by the special characteristics of product, they are not feasible. In our research, we propose a forecasting framework that predicts service demand of manufacturing organization by combining Case-based reasoning (CBR) and leveraging an unsupervised artificial neural network based clustering analysis (i.e., Self-Organizing Maps; SOM). We believe that this is one of the first attempts at applying unsupervised artificial neural network-based machine-learning techniques in the service forecasting domain. Our proposed approach has several appealing features : (1) We applied CBR and SOM in a new forecasting domain such as service demand forecasting. (2) We proposed our combined approach between CBR and SOM in order to overcome limitations of traditional statistical forecasting methods and We have developed a service forecasting tool based on the proposed approach using an unsupervised artificial neural network and Case-based reasoning. In this research, we conducted an empirical study on a real digital TV manufacturer (i.e., Company A). In addition, we have empirically evaluated the proposed approach and tool using real sales and service related data from digital TV manufacturer. In our empirical experiments, we intend to explore the performance of our proposed service forecasting framework when compared to the performances predicted by other two service forecasting methods; one is traditional CBR based forecasting model and the other is the existing service forecasting model used by Company A. We ran each service forecasting 144 times; each time, input data were randomly sampled for each service forecasting framework. To evaluate accuracy of forecasting results, we used Mean Absolute Percentage Error (MAPE) as primary performance measure in our experiments. We conducted one-way ANOVA test with the 144 measurements of MAPE for three different service forecasting approaches. For example, the F-ratio of MAPE for three different service forecasting approaches is 67.25 and the p-value is 0.000. This means that the difference between the MAPE of the three different service forecasting approaches is significant at the level of 0.000. Since there is a significant difference among the different service forecasting approaches, we conducted Tukey's HSD post hoc test to determine exactly which means of MAPE are significantly different from which other ones. In terms of MAPE, Tukey's HSD post hoc test grouped the three different service forecasting approaches into three different subsets in the following order: our proposed approach > traditional CBR-based service forecasting approach > the existing forecasting approach used by Company A. Consequently, our empirical experiments show that our proposed approach outperformed the traditional CBR based forecasting model and the existing service forecasting model used by Company A. The rest of this paper is organized as follows. Section 2 provides some research background information such as summary of CBR and SOM. Section 3 presents a hybrid service forecasting framework based on Case-based Reasoning and Self-Organizing Maps, while the empirical evaluation results are summarized in Section 4. Conclusion and future research directions are finally discussed in Section 5.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.2
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• pp.193-204
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• 1998

The single crystal of the $LiTaO_3$has large electro-optic effects, so it is applied to optical switch, acousto-optic deflector, and optical memory device as hologram using photorefractive effect. In this study, optic-grade undoped $LiTaO_3$and Fe:LiTaO$LiTaO_3$single crystals were grown by the Czochralski method and optical transmission and absorption spectrums were measured in the wavelength of UV-VIS range. The curie temperature was determined with DSC and by measuring capacitance for the grown undoped crystal and ceramic powder samples of various Li/Ta ratio. In case of having a 48.6 mol% $Li_2O$ as a starting Li/Ta ratio, the results of concentration variations were below 0.01 mol% $Li_2O$ all over the crystal, so it was confirmed that $LiTaO_3$single crystals were grown under congruent melting composition having optical homogeneity. The curie temperature of the Fe:$LiTaO_3$crystal was increased with increased with increased doped Fe concentrations;by the ratio of $7.5^{\circ}C$ increase per Fe 0.1 wt%. Also, the optical transmittance was about 78 %, which was sufficient for optical device.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.6
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• pp.36-45
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• 2011

Public open space(Gong-Gae-Gong-Ji) is an important part of the open-space system in an urban environment. Though part of the private sector, it has a significant public function as there are as always open to the free use of every citizen for rest and amenities. A field survey of the public open space of 71 major buildings was carried out to investigate the actual state of public open spaces in the city of Daegu. As a result of this investigation, several point of issues were discussed. In distribution by 'Gu', newly-emerging sub-centers of Daegu-City, such as Bug-Gu and Dalseo-Gu as well as downtown area have many public open spaces. By the use type of buildings, retail buildings such as shopping centers and SSM account for36.6%, business buildings21.1%, and residential and commercial complexes 15.5%, respectively. Location wise, the front areas accounted for the greatest amount(42.9%) with 1 in side area(20%), and 2 in the front/side area(20%), respectively. Degree of division was 1 spot type(45.7%), 2 division type(35.7%). The misuse of public open space for private use, such as shopping and parking lots, was26.6%. On the basis and analysis of the actual status, 6 improvement devices for public open spaces were suggested: 1) The improvement of the legal regulative system, 2) the establishment of design guidelines and strengthening of deliberation, 3) administrative and financial support, 4) periodic supervision and guidance, 5) installment of signs that shows the space is open for use to every citizen, and 6) the participation of citizens in management of public open space.

• Journal of Plant Biotechnology
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• v.42 no.3
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• pp.161-167
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• 2015

Sweetpotato [Ipomoea batatas (L.) Lam] grows well in harsh environmental conditions, and is cultivated as one of the top seven food crops in the world. Recently, sweetpotato is drawing interest from people as a healthy food because it is high in dietary fiber, vitamins, carotenoids and overall nutrition value. However, few studies have been conducted on sweetpotato genome sequencing in spite of its importance. This review is aimed at increasing the efficiency of sweetpotato genome sequencing research as well as establishing a base for gene utilization in order to control useful traits. Recently, animal and plant genome sequencing projects increased significantly. However, sweetpotato genome sequencing has not been performed due to polyploidy and heterogeneity problems in its genome. Meanwhile research on its transcriptome has been conducted actively. Recently, a draft of the diploid sweetpotato genome was reported in 2015 by Japanese researchers. In addition, the Korea-China-Japan Trilateral Research Association of Sweetpotato (TRAS) has conducted research on gene map construction and genome sequencing of the hexaploid sweetpotato Xushu 18 since 2014. The Bill & Melinda Gates Foundation launched the 'sweetpotato genomic sequencing to develop genomic tools for Sub-Sahara Africa breeding program'. The chloroplast genome sequence acquired during sweetpotato genome sequencing is used in evolutionary analyses. In this review, the trend of research in the sweetpotato genome sequencing was analyzed. Research trend analysis like this will provide researchers working toward sweetpotato productivity and nutrient improvement with information on the status of sweetpotato genome research. This will contribute to solving world food, energy and environmental problems.

• Korean Journal of Remote Sensing
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• v.27 no.4
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• pp.467-480
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• 2011

Spatial and temporal variabilities of NPP(Net Primary Production) retrieved from two satellite instruments, AVHRR(Advanced Very High Resolution Radiometer, 1981-2000) and MODIS(MODerate-resolution Imaging Spectroradiometer, 2000-2006), were investigated. The range of mean NPP from A VHRR and MODIS were estimated to be 894-1068 $g{\cdot}C/m^2$/yr and 610-694.90 $g{\cdot}C/m^2$/yr, respectively. The discrepancy of NPP between the two instruments is about 325 $g{\cdot}C/m^2$/yr, and MODIS product is generally closer to the ground measurement than AVHRR despite the limitation in direct comparison such as spatial resolution and vegetation classification. The higher NPP values over South Korea are related to the regions with higher biomass (e.g., mountains) and higher annual temperature. The interannual NPP trends from the two satellite products were computed, and both mean annual trends show continuous NPP increase; 2.14 $g{\cdot}C/m^2$/yr from AVHRR(1981-2000) and 6.08 $g{\cdot}C/m^2$/yr from MODIS (2000-2006) over South Korea. Specifically, the higher increasing trends over the Southwestern region are likely due to the increasing productivity of crop fields from sufficient irrigation and fertilizer use. The retrieved NPP shows a closer relationship between monthly temperature and precipitation, which results in maximum correlation during summer monsoons. The difference in the detection wavelength and model schemes during the retrieval can make a significant difference in the satellite products, and a better accuracy in the meterological and land use data and modeling applications will be necessary to improve the satellite-based NPP data.

• Journal of Food Hygiene and Safety
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• v.27 no.1
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• pp.30-36
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• 2012

This study was conducted to evaluate the microbiological hazard on nursery school children's hands and to investigate the reduction effect of hand washing education. A total of 59 nursery school children's hands were tested. The average number of total aerobic bacteria was $3.72{\pm}0.38log\;CFU/hand$. Five children's hands(2 male and 3 female) were positive(14.3%) for the coliform bacteria. These results showed that hand washing education are required repetitively. Among the pathogenic bacteria tested in this study, $Staphylococcus$ aureus and $Bacillus$ $cereus$ were detected in 9(25.7%) and 16(45.7%) out of 35 their hands, respectively. Twelve out of sixteen $B.$ $cereus$ isolates(70.0%) produced enterotoxin. The results indicate that the hand hygiene of nursery school children needs to be improved. Comparing before and after hand washing in educated and non-educated group, the reduction effect of total aerobic bacteria on their hands was 0.42 and 0.60 log CFU/hand, respectively. The educated group showed 0.18 log CFU/hand higher reduction effect than non-educated group but microorganism did not eliminate perfectly. From the results, using a hand sanitizer after washing with soap and the continuous hand washing education are required to control the contaminated bacteria on nursery school children's hands.

• 한국공간정보시스템학회:학술대회논문집
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• 2004.12a
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• pp.169-181
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• 2004

SK Telecom has already constructed GIMS system as the base common framework of LBS/GIS service system based on OGC(OpenGIS Consortium)'s international standard for the first mobile vector map service in 2002, But as service content appears more complex, renovation has been needed to satisfy multi-purpose, multi-function and maximum efficiency as requirements have been increased. This research is for preparation ion of GML3-based platform to upgrade service from GML2 based GIMS system. And with this, it will be possible for variety of application services to provide location and geographic data easily and freely. In GML 3.0, it has been selected animation, event handling, resource for style mapping, topology specification for 3D and telematics services for mobile LBS multimedia service. And the schema and transfer protocol has been developed and organized to optimize data transfer to MS(Mobile Stat ion) Upgrade to GML 3.0-based GIMS system has provided innovative framework in the view of not only construction but also service which has been implemented and applied to previous research and system. Also GIMS channel interface has been implemented to simplify access to GIMS system, and service component of GIMS internals, WFS and WMS, has gotten enhanded and expanded function.

• Korean Journal of Ecology and Environment
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• v.39 no.4 s.118
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• pp.462-470
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• 2006

The zooplankton community dynamics and grazing experiments was evaluated along a 40 km section of the lower Seomjin river system. Zooplankton was sampled twice a month from January 2005 to June 2006 at three sites (River mouth; RKO, Seomjin bridge: RK12 and Gurae bridge: RK36) in the main river channel. During the study period, the values of most limnological parameters in the three sites were fairly similar, except for conductivity. Annual variation of conductivity in River mouth and Seomjin bridge was more dramatic than which of the other site. There were statistically significant spatial and seasonal differences in zooplankton abundance (ANOVA, P<0.01). Total abundance of major zooplankton groups at both stations was much higher than in Gurae bridge. Among the macrozooplankton, cladocerans abundance was negligible in study sites during study periods. Community filtering rates (CFRs) for phytoplankton and bacteria varied from 0 to 50 mL $L^{-1}\;D^{-1}$ and from 0 to 45 mL $L^{-1}\;D^{-1}$, respectively. The spatial variation of CFRs for phytoplankton was significant (ANOVA, P<0.05). The CFRs of copepods for phytoplankton and bacteria was much higher than that of cladocerans at study sites. Total zooplankton filtering rates on bacteria were slightly lower than filtering rates on phytoplankton. The CFRs of microzooplankton (MICZ) for bacteria were much higher than for macrozooplankton (MACZ) at all sites. Considering the total zooplankton community, MICZ generally were more important than MACZ as grazers of bacteria and phytoplankton in freshwater zone, while MACZ were more important than MICZ as grazers of phytoplankton in brackish zone.

• Korean Journal of Ecology and Environment
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• v.48 no.1
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• pp.51-60
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• 2015

Forest vegetation of Youngbong (1,094 m) in Woraksan National Park is classified into mountain forest vegetation. Mountain forest vegetation is subdivided into deciduous broad-leaved forest, mountain valley forest, coniferous forest, riparian forest, afforestation and other vegetation. Including 84 communities of mountain forest vegetation and 7 communities of other vegetation, the total of 91 communities were researched; mountain forest vegetation classified by physiognomy classification are 39 communities deciduous broad-leaved forest, 26 communities of mountain valley forest, 6 communities of coniferous forests, 2 communities of riparian forests, 11 afforestation and 7 other vegetation. As for the distribution rate for surveyed main communities, Quercus mongolica, Quercus variabilis communities account for 40.879 percent of deciduous broad leaved forest, Fraxinus mandshurica - Cornus controversa community takes up 25.627 percent of mountain valley forest, Pinus densiflora community holds 75.618 percent of mountain coniferous forest holds. In conclusion, minority species consisting of Quercus mongolica, Pinus densiflora, Quercus variabilis, Fraxinus mandshurica, and Quercus serrata are distributed as dominant species of the uppermost part in a forest vegetation region in Woraksan National Park. In addition, because of vegetation succession and climate factors, numerous colonies formed by the two species are expected to be replaced by Quercus mongolica, Quercus variabilis and Fraxinus mandshurica which are climax species in the area.

• Journal of Korean Home Economics Education Association
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• v.16 no.4 s.34
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• pp.9-26
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• 2004

The purposes of this study are to develop and apply the student activity centered career exploring program and to verify effectiveness on the students' career maturity level. The subjects of this study were 137 students. 4 classes of a middle school in Jinju. They were divided into two groups, the experimental group and the control group. For experiment, the career exploring program was input to the experimental group for 14 class hours. The results of this study are as follows: 1. The student activity centered career exploring program applied to the unit $\ulcorner$The Choice of Career and Job Morals$\lrcorner$ was effective in raising the attitude of the career maturity level. As the result of verifying the differences. there was a statistically significant difference between the experimental group and the control group in the planning quality and the attitude of works. 2. The student activity centered career exploring program applied to the unit $\ulcorner$The Choice of Career and Job Morals$\lrcorner$ was effective in raising the ability field of the career maturity level. The experimental group showed more statistically meaningful differences in the knowledge of jobs, the information exploring, and the self-understanding than the control group. Consequently. the effects of the student activity centered career exploring program on the career maturity level in the unit $\ulcorner$The Choice of Career and Job Morals$\lrcorner$. all the fields of the career maturity level showed the statistically meaningful differences except the independence quality of the attitude field and the decision making of the ability field. So it is concluded that the experiment program elevated the students' career maturity level. However. as the result of analysing independent sample t-test of the pre-test and the post-test. the program was ineffective in the independence quality and the decision making. When this career exploring program is applied to the unit $\ulcorner$The Choice of Career and Job Morals$\lrcorner$. it is recommended to strengthen the activities to cultivate the independence quality and the decision making power.