• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.6
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• pp.115-121
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• 2013

This paper related with the DSE-MMA (Dithered Sign-Error MMA) that is the simplification of computational arithmetic number in blind equalization algorithm in order to compensates the intersymbol interference which occurs the passing the nonlinear communication channel in the presence of the band limit and phase distortion. The SE-MMA algorithm has a merit of H/W implementation for the possible to reduction of computational arithmetic number using the 1 bit quantizer in stead of multiplication in the updating the equalizer tap weight. But it degradates the overall blind equalization algorithm performance by the information loss at the quantization process compare to the MMA. The DSE-MMA which implements the dithered signed-error concepts by using the dither signal before qualtization are added to MMA, then the improved SNR performance which represents the roburstness of equalization algorithm are obtained. It has a concurrently compensation capability of the amplitude and phase distortion due to intersymbol interference like as the SE-MMA and MMA algorithm. The paper uses the equalizer output signal, residual isi, MD, MSE learning curve and SER curve for the performance index of blind equalization algorithm, and the computer simulation were performed in order to compare the SE-MMA and DSE-MMA applying the same performance index. As a result of simulation, the DSE-MMA can improving the roburstness and the value of every performance index after steady state than the SE-MMA, and confirmed that the DSE-MMA has slow convergence speed which meaning the reaching the seady state from initial state of adaptive equalization filter.

• Journal of the Economic Geographical Society of Korea
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• v.16 no.2
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• pp.310-321
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• 2013

The paper aims to understand the concept of social innovation and its development stages emerging as a new regional development policy trend and to define the role of public sector for social innovation. Spatial policy issues that urban development corporations to carry out development projects for regional policy need to deal with have expanded to include crucial social issues such as poverty, quality of life and happiness. Therefore it is increasingly significant for them to take social innovation into consideration. In this context, this study formulates evaluation framework for the role of public sector in social innovation and investigates its position and limitation in social innovation practices. As a result, almost all corporations have made various efforts for promoting both public purposes of housing and land development and social contribution for the community. However, few corporations have achieved organizational capacity building and idea implementation for social innovation. Growing demand for social innovation in both spatial and regional policies tends to bring up profound challenges to public regional development agencies including urban development corporations. It is then a time to seek to carry out related researches and policy option formulation for social innovation in the near future.

• Journal of Korea Water Resources Association
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• v.41 no.8
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• pp.761-772
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• 2008

The object of this study is to develop the model that solves the numerically difficult problems in hydraulic engineering and to demonstrate the applicability of this model by means of various test examples, such as, verification in the gradually varied unsteady condition, three steady flow problems with the change of bottom slope with exact solution, and frictional bed with analytical solution. The governing equation of this model is the integral form of the Saint-Venant equation satisfying the conservation laws, and finite volume method with the Riemann solver is used. The evaluation of the mass and momentum flux with the HLL Riemann approximate solver is executed. MUSCL-Hancock scheme is used to achieve the second order accuracy in space and time. This study introduce the new and simple technique to discretize the source terms of gravity and hydrostatic pressure force due to longitudinal width variation for the balance of quantity between nonlinear flux and source terms. The results show that the developed model's implementation is accurate, robust and highly stable in various flow conditions with source terms, and this model is reliable for one-dimensional applications in hydraulic engineering.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.4
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• pp.143-154
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• 2012

As demand of water resources and attentions to changes in climate (e.g., due to ENSO) increase, long/short term prediction of precipitation is getting necessary in water planning. This research evaluated the ability of MM5 to predict precipitation in the Tampa Bay region over 23 year period from 1986 to 2008. Additionally MM5 results were statistically bias-corrected using observation data at 33 stations over the study area using CDF-mapping approach and evaluated comparing to raw results for each ENSO phase (i.e., El Ni$\tilde{n}$o and La Ni$\tilde{n}$a). The bias-corrected model results accurately reproduced the monthly mean point precipitation values. Areal average daily/monthly precipitation predictions estimated using block-kriging algorithm showed fairly high accuracy with mean error of daily precipitation, 0.8 mm and mean error of monthly precipitation, 7.1 mm. The results evaluated according to ENSO phase showed that the accuracy in model output varies with the seasons and ENSO phases. Reasons for low predictions skills and alternatives for simulation improvement are discussed. A comprehensive evaluation including sensitivity to physics schemes, boundary conditions reanalysis products and updating land use maps is suggested to enhance model performance. We believe that the outcome of this research guides to a better implementation of regional climate modeling tools in water management at regional/seasonal scale.

• Management & Information Systems Review
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• v.36 no.2
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• pp.37-58
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• 2017

This study analyzed the effect of how much work-family conflict affect on job involvement and life satisfaction and the effect of moderating effect of demographic characteristics in Mongolia SMEs. For these, this study explores theoretical background about work-family conflict(work interference with family conflict, family interference work conflict), job involvement and life satisfaction, then derived research framework and hypotheses from exploration of theoretical background. According to hypothesis testing result, first, work interference with family conflict has negative effect on life satisfaction. Second, family interference work conflict has negative effect on job involvement and life satisfaction. Third, there is not significance of moderating effect of demographic characteristics between work-family conflict and job involvement/life satisfaction. The main implication of this study is to promote leader's change of awareness about work-family conflict management, to institute flexible work arrangements and selective implementation of a maternity leave and a parental leave and to establish an evaluation system.

• Korea Journal of Hospital Management
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• v.7 no.4
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• pp.1-23
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• 2002

This study examined the influence of the separation of prescribing and dispensing roles(SPD) policy implemented in Korea in July 2000, especially on the change in the net profit of medical institutions. Using the data set from the Korea's National Health Insurance and the previous research, this study elicited the following main results. First, tertiary care institutions was estimated to lose about 631 billion won after the SPD policy. Second, general hospitals and hospitals gained about 557 billion and 564 billion won, respectively. Third, it is shown that clinics also gained 389-659 billion won. Finally, however, the change in net profit of medical institutions after the SPD policy largely depends on different estimation models. Moreover, it also varies from the assumptions on the price differential of a reimbursable drug which worked as cross-subsidy to insufficient physician's fee before the SPD policy. Despite such limitations as lack of data outside of the National Health Insurance's coverage, this study differs from others. This is the first research to explore the effect of the SPD policy on different types of medical institutions and to attempt to purely focus on the SPD policy. In this study, we can draw the policy implication that preparing for a policy change, the government should set up the policy evaluation system to collect the concerned data and develop the methodologies in advance to the policy implementation.

• The KIPS Transactions:PartA
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• v.16A no.2
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• pp.101-112
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• 2009

Existing techniques for defragmentation of the file system need intensive disk operation for some periods at specific time such as disk defragmentation program. In this paper, for solving this problem, we design and implement the automatic and continuous defragmentation free system by distributing the disk operation. We propose the Automatic Layout Scoring(ALS) mechanism for measuring defragmentation degree and suggest the Lazy Copy mechanism that copies the defragmented data at idle time for scattering the disk operation. We search the defragmented file by Automatic Layout Scoring mechanism and then find for empty spaces for that searched file. After lazy copy of searched fils to empty space for preventing that file from being lost, the algorithm solves the defragmentation problem by updating the I-node of that file. We implement these algorithms in Linux and evaluate them for small and defragmented file to get the layout scoring. We outperform the Linux EXT2 file system by $2.4%{\sim}10.4%$ in layout scoring evaluation. And the performance of read and write for various file size is better than the EXT2 by $1%{\sim}8.5%$ for write performance and by $1.2%{\sim}7.5%$ for read performance. We suggest this system for solving the problem of defragmentation automatically without disturbing the I/O task and manual management.

• The Transactions of the Korea Information Processing Society
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• v.7 no.11S
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• pp.3702-3713
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• 2000

Telecommunications standards have two different types of regulations: one is a law. enacted by government which all telecommunications related industries must observe. The other is a recommendatory standards. formulated by either government agency or some standardization organizations. Observation of these standards is not obligatory. However, technical standards are strict laws and ordinances based on common judgement and various conditions for evaluation of levels and limits. This paper deals with enhancing productivity of enactment and revision of technical standards. Through database of above related information we secure information continuity and public property of cyber space for the public. In this paper. we also classify recent data within the website in and out of the country offering four different methods of information retrieval and management system. The four retrieval methods suggested in this paper are itemized keyword retrieval. hierarchical retrieval, regulatory keyword retrieval and chronological keyword retrieval. These various retrieval methods provide the public with information of enactment and amendment of laws and regulations in the cyber space. thereby guarantees the sharing of information. Finally the important feature of the information retrieval system implemented in this paper is the online updating capability of law and regulations through the internet.

• Journal of Veterinary Clinics
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• v.33 no.2
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• pp.107-112
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• 2016

The objective of this study was to determine potential contributing factors associated with biosecurity level of farrow-to-finish pig farms and to develop a classification tree model to explore how these factors related to each other based on prediction model. To this end, the author analyzed data (n = 193) extracted from a cross-sectional study of 344 farrow-to-finish farms which was conducted between March and September 2014 aimed to explore swine disease status at farm level. Standardized questionnaires with information about basic demographical data and management practices were collected in each farm by on-site visit of trained veterinarians. For the classification of the data sets regarding biosecurity level as a dependent variable and predictor variables, Chi-squared Automatic Interaction Detection (CHAID) algorithm was applied for modeling classification tree. The statistics of misclassification risk was used to evaluate the fitness of the model in terms of prediction results. Categorical multivariate input data (40 variables) was used to construct a classification tree, and the target variable was biosecurity level dichotomized into low versus high. In general, the level of biosecurity was lower in the majority of farms studied, mainly due to the limited implementation of on-farm basic biosecurity measures aimed at controlling the potential introduction and transmission of swine diseases. The CHAID model illustrated the relative importance of significant predictors in explaining the level of biosecurity; maintenance of medical records of treatment and vaccination, use of dedicated clothing to enter the farm, installing fence surrounding the farm perimeter, and periodic monitoring of the herd using written biosecurity plan in place. The misclassification risk estimate of the prediction model was 0.145 with the standard error of 0.025, indicating that 85.5% of the cases could be classified correctly by using the decision rule based on the current tree. Although CHAID approach could provide detailed information and insight about interactions among factors associated with biosecurity level, further evaluation of potential bias intervened in the course of data collection should be included in future studies. In addition, there is still need to validate findings through the external dataset with larger sample size to improve the external validity of the current model.

• 대한공업교육학회지
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• v.44 no.1
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• pp.162-189
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• 2019

The purpose of this study is to develop and apply a Design Thinking-based Maker education program utilizing Arduino for middle school students. The study progress was made in four stages of preparation, development, implementation and evaluation according to the PDIE model. In this study, experts were verified for validity and pre-applied to students to improve the maker education program developed based on literature review. Then, it was applied to middle school club classes to check the effects through analysis of quantitative and qualitative data. In addition, the development of the program was completed by supplementing the improvements found in the course. The results of this study are as follows. First, the topics of the maker education program that can be used in middle schools were selected in consideration of the analysis of the 2015 revised curriculum, methods to using the Arduino, and social interest. Second, the program developed based on the selected topic consists of 4 classes of maker basic learning and 16 classes of design thinking-based maker activities. Third, the developed maker education program had a significant effect in improving STEAM literacy of middle school students, but did not have any significant effect in the interest in technology and orientation towards an engineering career. Fourth, learners were interested in the activities of designing and freely making by themselves, and they positively evaluated the experience of realizing the physical computing with Arduino. In addition, they practiced the spirit of a maker, such as autonomously collecting data and sharing them with colleagues, etc. while acting as a maker.