• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.4
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• pp.611-619
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• 2018

Basalt powder sludge (abbreviated BPS) is an inevitable industry by product resulted from the stone processing. Recently, demands for natural materials have been increasing in the construction and landscaping fields, therefore, amounts of BPS have been also increasing. Since most of BPS are used as landfill and earth soil, it is necessary to figure out to expedite their utilization. In this study, by considering the characteristics of precipitation of Jeju, effectiveness of BPS as a filler for asphalt compounds mixed with cement were analyzed. As a result, BPS satisfies quality criterion required in KS F 3501. Marshall mixing designs were performed to determine the optimal asphalt content for the Modified recycling asphalt mixture (27% recycling aggregate) and the Normal asphalt mixture. Effectiveness of BPS were identified by the Marshall Stability Test with the mixing ratio (level 3) of two asphalt compounds and composition ration (level 3) of BPS and cement. Performance of asphalt compounds shown appropriate effect of mixing and composition ratios of the filler were assessed. Test results show that two types of asphalt compounds satisfy the quality standards of the MLIT (2015). Therefore, BPS could be used as filler for asphalt compounds.

• Journal of the Korean Society for Library and Information Science
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• v.51 no.4
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• pp.99-120
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• 2017

In order to develop a semiautomatic support system that allows researchers concerned to efficiently analyze the technical trends for the ever-growing industry and market. This paper introduces a couple of Korean sentence generation models that can automatically generate definitional statements as well as descriptions of technical terms and concepts. The proposed models are based on a deep learning model called LSTM (Long Sort-Term Memory) capable of effectively labeling textual sequences by taking into account the contextual relations of each item in the sequences. Our models take technical terms as inputs and can generate a broad range of heterogeneous textual descriptions that explain the concept of the terms. In the experiments using large-scale training collections, we confirmed that more accurate and reasonable sentences can be generated by CHAR-CNN-LSTM model that is a word-based LSTM exploiting character embeddings based on convolutional neural networks (CNN). The results of this study can be a force for developing an extension model that can generate a set of sentences covering the same subjects, and furthermore, we can implement an artificial intelligence model that automatically creates technical literature.

• Korean Journal of Poultry Science
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• v.16 no.1
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• pp.29-52
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• 1989

Selection of breeds, adequate environment and sanitary condition must be considered to improve production ability. Minimizing of production cost through reasonable management and farm system can introduce maximizing net income. Followings are the summary of poultry industry in Japan： (1) To decreasing consumers Price and to gurantee the quality of eggs, poultry farms changed their farm system as complex which contain feed factory, GP center and processing factory as well as raising laying hens. (2) Broiler farms moved from suburbs to several remote from cites owing to development of transferation , and rising price of land. (3) The egg Price in Japan was depended on season. From fall to spring, the Price was usually rised due to increased consumption, and from May to August the price always dropped. (4) The average production per one you was around 17kg/hen and average feed consumption was around 2.45. Rearing rate was around 98.5% and motality of hens was around 7%. And one person reared 15,000-20,000 hens in over 100 thousand chicken reared farms even though average ability per person showed 3,266 hens.

• Resources Recycling
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• v.22 no.1
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• pp.64-71
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• 2013

Mineral carbonation has been proposed as a possible way for $CO_2$ sequestration. The electric arc furnace slags consist of calcium, magnesium and aluminum silicates in various combinations. If they could be used instead of natural mineral silicates for carbonation, considerable energy savings and $CO_2$ emissions reductions could be achieved. Indirect aqueous carbonation of the slags consists of two steps, extraction of calcium and carbonation. Acetic acid leaching of electric arc furnace slags had been already studied to extract Ca in them, but it was reported that the carbonation of the extracted $Ca^{2+}$ in the leached solution would suffer from too slow kinetics, even at high pressure of $CO_2$. In this work, to develop more efficient extraction of the electric arc furnace slags, hydrochloric acid leaching to separate calcium from them was studied, and the results were compared with the acetic acid ones. The phase boundary between $Ca^{2+}$ and $CaCO_3$ in the solution with pH was determined by thermodynamic calculations. Hydrochloric acid was more effective than acetic acid for the extraction of Ca in electric arc furnace slag, and there is a possibility to recycle an unreacted hydrochloric acid in the leached solution by electrolysis or evaporation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.4
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• pp.195-206
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• 1980

Fish were grown in a water recycling rearing system consisting of a filter system, of which the area is about $30\;m^2$ and the volume of filter gravels is about $15\;m^3$, 6 rearing and 2 supplementary tans about $7\;m^2$ of surface area each. The results for 180 days from April 18 to October 14,1980 are summarized as following: One rearing tank was used for main experiment stocked with an equal number, and weight of each Israeli strain and $F_1$, hybrid between this strain and Korean local strain of common carp. Gross total production was 461 kg with a net production of 395 kg, and the Israeli strain grew to about 8 times initial weight and the hybrid about 6 times. Based on an analysis of results of the above mentioned main experiment and the other miscellaneous fish grown in the remaining tanks, it was considered to be feasible to implement a commercial production in this system by improving parts of the system and adding a number of the units. A special problem seems to be an adoption of more effective aeration device when fish loading increases. A solid waste removal system was deviced by use of by-pass flow ana this system worked very efficiently in view of supply water economy. A serious problem encountered in this experiment was heavy outbreaks of the gill-fluke, Dactylogyrus sp. which was relatively easily eradicated with Dipterex or DDVP treatment in the first trials, but later on strains which were resistant to any of these chemicals appeared.

• Korean Chemical Engineering Research
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• v.58 no.4
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• pp.588-595
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• 2020

Prediction and control of nitrogen oxides (NO_x) emission is of great interest in industry due to stricter environmental regulations. Herein, we propose an artificial intelligence (AI)-based framework for prediction of NO_x emission. The framework includes pre-processing of data for training of neural networks and evaluation of the AI-based models. In this work, Long-Short-Term Memory (LSTM), one of the recurrent neural networks, was adopted to reflect the time series characteristics of NO_x emissions. A decision tree was used to determine a time window of LSTM prior to training of the network. The neural network was trained with operational data from a heating furnace. The optimal model was obtained by optimizing hyper-parameters. The LSTM model provided a reliable prediction of NO_x emission for both training and test data, showing an accuracy of 93% or more. The application of the proposed AI-based framework will provide new opportunities for predicting the emission of various air pollutants with time series characteristics.

• Resources Recycling
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• v.22 no.2
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• pp.29-36
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• 2013

Although Korean domestic production of flat panel displays totalled more than 48 trillion KRW in 2007, most of the flat panel display wastes have been land-filled or incinerated, which greatly overshadows Korean national prestige as a world leading producer and developer of flat panel display devices. Countries such as Japan or EU possess quite limited land-fill capability and have sought ways to dispose of WEEEs from environment-friendly perspective rather than recovery of valuable materials from the wastes. Considering relatively short cycle of about 5 years for flat panel display devices, it is estimated that more than 5 million units will be accumulated as wastes by 2015. Urban mining is a most suitable countermeasures against China's monopoly of rare and rare earth metals, which are contained in flat panel display wastes. Therefore, materials recycling of waste LCD units has to be developed and commercialized soon enough for economic and environment-friendly recovery of valuable resources hidden in LCD wastes.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.4
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• pp.1151-1159
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• 2014

In this study, two global simple indices are used to investigate climate variability and change in observations. Land-Ocean Contrast (LOC) is an index of area-averaged surface temperature contrast between land and ocean. Meridional Temperature Gradient (MTG) is defined as the mean meridional temperature gradient in the Northern Hemisphere from mid to high latitude and sub-tropical zonal bands. These indices have direct or indirect effects on changing in atmospheric circulations and atmospheric moisture transport from north-south or east-west into East Asia (EA). In addition, warm season hydrometeorology in EA is highly associated with water supplies for coupled human and natural systems including drinking water, irrigation, hydropower generation as well as fisheries. Therefore, in this study, we developed an empirical separation approach for summer rainfall from typhoon and monsoon. An exploratory analysis was also conducted to identify the regional patterns of summer monsoon precipitation over the Korean peninsula within the context of changes in different types of temperature gradients. The results show significant and consistent changes in summer monsoon rainfall during the summer season (June-September) in South Korea.

• Journal of Digital Convergence
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• v.12 no.6
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• pp.13-22
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• 2014

This study analyzed the globalization policy of ICT SMEs and ventures using cognitive map analysis and derived the priority to importance about action plans using AHP model, while the globalization paradigm has been rapidly changing in the ICT industry. Empirical results showed that policy tool variables should be needed to develop because policy goal variables are generally presented more than policy tool variables. In addition, this cognitive map could be characterized by a scarcity of feedback loops which means policy landscape for ICT SMEs and ventures' globalization is unilateral rather than cyclical to reach policy goal from policy tools. Another finding is that creative economy policy variable was not observed as policy tool variable but as policy goal variable. This means creative economy can be implemented through support for ICT SMEs and ventures' globalization. Finally, for detailed policy measures, installation of global start-up center, recruiting and utilization of global specialists, revitalization of ICT R&D international collaboration study, enlargement of global investment network, accompanied overseas advance of large enterprises and SMEs are presented in order in terms of the importance of policy priority.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.3
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• pp.147-161
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• 2017

Korea is a country having shortage of natural resources, but to overcome this issue and to nurture national competitiveness it is challenging for national-lead economic policy, citizen's dedicated efforts and technological innovation for achieving economic growth. Since the financial crisis, the government has boldly promoted policies to nurture venture companies to make structural adjustments for the sophistication of the industrial structure and job creation. Various policies for establishing the foundation of the entrepreneurial ecosystem in which the process of start-up, growth, recovery and reinvest are virtually circulated are presented by the Business Incubators. Recently the Business Incubators neither present a direction differentiated from the vocation of Business Incubator, and nor the operating methods for leading the changing of Business Incubator environment, which threatening the role of Incubating and growing early startup companies. In order to explore the development change of the business incubator, in this research we analyzed the published papers from 1998 to 2016 of business incubator government polices, research methods, related research topics and other major variables. The analysis of the research trends of business incubator revealed the lack of depth case studies, diversity of research topics, and the study of certain limited variables. For the development of the business incubator, case studies of the institutions which carried out excellent incubator and research on the incubation system of the institutions, that are similar to the incubation center are required. This research suggest further research on the case studies of excellent business incubator and agencies, and the center director and manager, which is the center of human resources, and hopes for the revitalization of business incubator researches.