• Journal of Intelligence and Information Systems
• /
• v.20 no.2
• /
• pp.93-107
• /
• 2014

In this paper, we report what we have observed with regard to user-perspective issue clustering based on multi-layered two-mode network analysis. This work is significant in the context of data collection by companies about customer needs. Most companies have failed to uncover such needs for products or services properly in terms of demographic data such as age, income levels, and purchase history. Because of excessive reliance on limited internal data, most recommendation systems do not provide decision makers with appropriate business information for current business circumstances. However, part of the problem is the increasing regulation of personal data gathering and privacy. This makes demographic or transaction data collection more difficult, and is a significant hurdle for traditional recommendation approaches because these systems demand a great deal of personal data or transaction logs. Our motivation for presenting this paper to academia is our strong belief, and evidence, that most customers' requirements for products can be effectively and efficiently analyzed from unstructured textual data such as Internet news text. In order to derive users' requirements from textual data obtained online, the proposed approach in this paper attempts to construct double two-mode networks, such as a user-news network and news-issue network, and to integrate these into one quasi-network as the input for issue clustering. One of the contributions of this research is the development of a methodology utilizing enormous amounts of unstructured textual data for user-oriented issue clustering by leveraging existing text mining and social network analysis. In order to build multi-layered two-mode networks of news logs, we need some tools such as text mining and topic analysis. We used not only SAS Enterprise Miner 12.1, which provides a text miner module and cluster module for textual data analysis, but also NetMiner 4 for network visualization and analysis. Our approach for user-perspective issue clustering is composed of six main phases: crawling, topic analysis, access pattern analysis, network merging, network conversion, and clustering. In the first phase, we collect visit logs for news sites by crawler. After gathering unstructured news article data, the topic analysis phase extracts issues from each news article in order to build an article-news network. For simplicity, 100 topics are extracted from 13,652 articles. In the third phase, a user-article network is constructed with access patterns derived from web transaction logs. The double two-mode networks are then merged into a quasi-network of user-issue. Finally, in the user-oriented issue-clustering phase, we classify issues through structural equivalence, and compare these with the clustering results from statistical tools and network analysis. An experiment with a large dataset was performed to build a multi-layer two-mode network. After that, we compared the results of issue clustering from SAS with that of network analysis. The experimental dataset was from a web site ranking site, and the biggest portal site in Korea. The sample dataset contains 150 million transaction logs and 13,652 news articles of 5,000 panels over one year. User-article and article-issue networks are constructed and merged into a user-issue quasi-network using Netminer. Our issue-clustering results applied the Partitioning Around Medoids (PAM) algorithm and Multidimensional Scaling (MDS), and are consistent with the results from SAS clustering. In spite of extensive efforts to provide user information with recommendation systems, most projects are successful only when companies have sufficient data about users and transactions. Our proposed methodology, user-perspective issue clustering, can provide practical support to decision-making in companies because it enhances user-related data from unstructured textual data. To overcome the problem of insufficient data from traditional approaches, our methodology infers customers' real interests by utilizing web transaction logs. In addition, we suggest topic analysis and issue clustering as a practical means of issue identification.

• Journal of Intelligence and Information Systems
• /
• v.22 no.4
• /
• pp.193-215
• /
• 2016

In recent years, the proliferation of diverse social networking services has led users to use many mediums simultaneously depending on their individual purpose and taste. Besides, while collecting information about particular themes, they usually employ various mediums such as social networking services, Internet news, and blogs. However, in terms of management, each document circulated through diverse mediums is placed in different categories on the basis of each source's policy and standards, hindering any attempt to conduct research on a specific category across different kinds of sources. For example, documents containing content on "Application for a foreign travel" can be classified into "Information Technology," "Travel," or "Life and Culture" according to the peculiar standard of each source. Likewise, with different viewpoints of definition and levels of specification for each source, similar categories can be named and structured differently in accordance with each source. To overcome these limitations, this study proposes a plan for conducting category mapping between different sources with various mediums while maintaining the existing category system of the medium as it is. Specifically, by re-classifying individual documents from the viewpoint of diverse sources and storing the result of such a classification as extra attributes, this study proposes a logical layer by which users can search for a specific document from multiple heterogeneous sources with different category names as if they belong to the same source. Besides, by collecting 6,000 articles of news from two Internet news portals, experiments were conducted to compare accuracy among sources, supervised learning and semi-supervised learning, and homogeneous and heterogeneous learning data. It is particularly interesting that in some categories, classifying accuracy of semi-supervised learning using heterogeneous learning data proved to be higher than that of supervised learning and semi-supervised learning, which used homogeneous learning data. This study has the following significances. First, it proposes a logical plan for establishing a system to integrate and manage all the heterogeneous mediums in different classifying systems while maintaining the existing physical classifying system as it is. This study's results particularly exhibit very different classifying accuracies in accordance with the heterogeneity of learning data; this is expected to spur further studies for enhancing the performance of the proposed methodology through the analysis of characteristics by category. In addition, with an increasing demand for search, collection, and analysis of documents from diverse mediums, the scope of the Internet search is not restricted to one medium. However, since each medium has a different categorical structure and name, it is actually very difficult to search for a specific category insofar as encompassing heterogeneous mediums. The proposed methodology is also significant for presenting a plan that enquires into all the documents regarding the standards of the relevant sites' categorical classification when the users select the desired site, while maintaining the existing site's characteristics and structure as it is. This study's proposed methodology needs to be further complemented in the following aspects. First, though only an indirect comparison and evaluation was made on the performance of this proposed methodology, future studies would need to conduct more direct tests on its accuracy. That is, after re-classifying documents of the object source on the basis of the categorical system of the existing source, the extent to which the classification was accurate needs to be verified through evaluation by actual users. In addition, the accuracy in classification needs to be increased by making the methodology more sophisticated. Furthermore, an understanding is required that the characteristics of some categories that showed a rather higher classifying accuracy of heterogeneous semi-supervised learning than that of supervised learning might assist in obtaining heterogeneous documents from diverse mediums and seeking plans that enhance the accuracy of document classification through its usage.

• Resources Recycling
• /
• v.26 no.6
• /
• pp.29-37
• /
• 2017

Nuclear fuel cladding tube is fabricated by pilgering and annealing process. In order to remove impurity and oxygen layer on the surface, pickling process is carried out. When Zirconium(Zr) is dissolved and saturated in acid solution during the pickling process, all the waste acid including Zr is disposed. Therefore, $BaF_2$ is added into the waste acid to extract Zr and $Ba_2ZrF_8$ is subsequently formed. To recycle Zr by electrowinning process, $Ba_2ZrF_8$ is used as electrolyte, but it has high melting point ($1053^{\circ}C$). $ZrF_4$ should be added into $Ba_2ZrF_8$ to decrease the melting point. In this paper, it was investigated that $Ba_2ZrF_8$ was separated to $BaF_2$ and $ZrF_4$ by vacuum distillation. Firstly, $BaF_2$ with different particle size ($1{\mu}m$, $35{\mu}m$, $110{\mu}m$) was added into the waste acid and the respective precipitation property was estimated. $BaF_2$ obtained by vacuum distillation was shattered by ball-milling with different time. The precipitation efficiency was compared with $1{\mu}m$ of ${BaF_2}^{\prime}s$ one, which was not used as precipitation agent.

• KSBB Journal
• /
• v.24 no.4
• /
• pp.383-392
• /
• 2009

Xanthii fructus which is well known as "Chang-ihjah" in Korea is the dried fruit of Xanthium strumarium L. (or Xanthium sibiricum PATR. Ex WIDD., Asteraceae. XS). Water extract of this fruit has been used for treatment of various inflammatory diseases such as tympanitis, allergic rhinitis, or ozena as alternative therapy material usually by oral administration in far Eastern countries including Korea. In this study, the effect of XS extract (XS-E) or XS-30% acetone fraction layer (XS-30% AFL) on the differentiation of $CD4^+$ T cells isolated from NC/Nga mouse and the production of IL-17 was investigated. The experimental results showed that $100\;{\mu}g$/mL of XS-E could decrease the production of IL-17 by $CD4^+$ Th17 cells by 2 fold and only $20\;{\mu}g$/mL of XS-30% AFL could inhibit 3.5 fold. The amount of IL-17A and IL-22 mRNA determined by real-time PCR was decreased remarkably when XS-E or XS-30% AFL was treated on $CD4^+$ Th17 cells(p<0.01, p<0.001). The amount of IL-17A protein determined by ELISA was also decreased remarkably(p<0.05, p<0.001). To study the effect of XS-E or XS-30% AFL on the proliferation of Th17 cells, $CD4^+$ T cells of a NC/Nga mouse was firstly differentiated by rIL-6/TGF-$\beta$ and then stimulated by rIL-23. The control group of Th17 cells were doubled every each day, while those of XS-E or XS-30% AFL treated group were shown to be delayed remarkably by these extracts. In conclusion, XS can inhibit the differentiation of Th17 cells of NC/Nga mouse and the production of IL-17 successfully, which may be a beneficial result for the treatment of atopic skin dermatitis.

• Journal of Bio-Environment Control
• /
• v.24 no.2
• /
• pp.93-99
• /
• 2015

The purpose of this study was to determine the appropriate temperature for water curtain in greenhouses equipped with recirculated water curtain system. The study analyzed the changes in air temperature in non-heated greenhouses for strawberry cultivation based on outdoor temperature, water curtain temperature and night time. Three greenhouse units were used for this study: The first unit was assigned as a control (no water curtain system), two other greenhouses were equipped with recirculated water curtain system with water curtain temperatures of $10^{\circ}C$ and $15^{\circ}C$, respectively. Analysis showed that the indoor temperatures were directly correlated with the outdoor temperature in all experimental greenhouses. Heat insulating effect of $15^{\circ}C$ water curtain was increased by $1.3^{\circ}C$ compared to that in $10^{\circ}C$ water curtain system. The $15^{\circ}C$ water curtain treatment showed the highest average temperature and less temperature variation in comparison with control and $10^{\circ}C$ water curtain treatment. To maintain indoor temperature at $5^{\circ}C$, water curtain temperature of $10^{\circ}C$ was suitable when outdoor minimum and average temperatures were -1.3 and $1.5^{\circ}C$, and water curtain temperature of $15^{\circ}C$ was suitable when outdoor minimum and average temperatures were -4.7 and $-0.2^{\circ}C$, respectively. The highest temperature in greenhouses according to measurements in different periods of night time was observed after sunset (18:30-20:30), and the lowest temperature before sunrise (05:00-07:00). Water curtain maintained a target indoor temperature by acting as a layer of heat transfer insulator which decreased heat loss from greenhouses. Therefore, water temperature in recirculating water curtain systems should be determined by considering outdoor temperatures, changes in temperature at different periods of night time, and cultivated crop.

• Asian Journal of Turfgrass Science
• /
• v.24 no.1
• /
• pp.45-49
• /
• 2010

Research on nitrate-nitrogen ($NO_3-N$) leaching in turfgrass indicates that in most cases leaching poses minimal risk to the environment. Although there have been many studies investigating $NO_3-N$ leaching, there has been little research to investigate the effect of compaction level and rootzone mix on nitrogen (N) leaching. The research objective is to determine the effect of compaction level and rootzone mix on nitrogen leaching. The four rootzone mixes are 76.0:24.0, 80.8:19.2, 87.0:13.0 and 93.7:6.3 % (sand:soil). The four levels of compaction energies are 1.6, 3.0, 6.1, and 9.1 J $cm^{-2}$. Nitrogen was applied using urea at a rate of 147 kg $ha^{-1}$ split among three applications. Rootzone was packed into a polyvinylchloride pipe with a perforated bottom to facilitate drainage. Rootzone depth was 30 cm over a 5 cm gravel layer. Each column was sodded with Poa pratensis L. Hoagland solution designed for coolseason grasses, minus N, was used to ensure adequate nutrition in the rootzone. Turf grass quality and clipping yield were recorded from each tube at two-week intervals. The clippings were oven-dried at a temperature of $67^{\circ}C$ for 24 h and weighed. At the end of the study, root dry weight was determined by washing and oven-drying samples at $67^{\circ}C$ for 24 h. Leachate solution was collected weekly for analysis. More than 6.1 J $cm^{-2}$ of compaction energy increased possibilities of surface runoff. The compaction energy between 3.0 and 6.1 J $cm^{-2}$ produced more clipping dry weight and less N leaching than 9.1 J $cm^{-2}$.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.26 no.12
• /
• pp.605-619
• /
• 2014

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2013. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of fluid machinery, pipes and relative parts including orifices, dampers and ducts, fuel cells and power plants, cooling and air-conditioning, heat and mass transfer, two phase flow, and the flow around buildings and structures. Research issues dealing with home appliances, flows around buildings, nuclear power plant, and manufacturing processes are newly added in thermal and fluid engineering research area. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results for general analytical model for desiccant wheels, the effects of water absorption on the thermal conductivity of insulation materials, thermal properties of Octadecane/xGnP shape-stabilized phase change materials and $CO_2$ and $CO_2$-Hydrate mixture, effect of ground source heat pump system, the heat flux meter location for the performance test of a refrigerator vacuum insulation panel, a parallel flow evaporator for a heat pump dryer, the condensation risk assessment of vacuum multi-layer glass and triple glass, optimization of a forced convection type PCM refrigeration module, surface temperature sensor using fluorescent nanoporous thin film. In the area of pool boiling and condensing heat transfer, researches on ammonia inside horizontal smooth small tube, R1234yf on various enhanced surfaces, HFC32/HFC152a on a plain surface, spray cooling up to critical heat flux on a low-fin enhanced surface were actively carried out. In the area of industrial heat exchangers, researches on a fin tube type adsorber, the mass-transfer kinetics of a fin-tube-type adsorption bed, fin-and-tube heat exchangers having sine wave fins and oval tubes, louvered fin heat exchanger were performed. (3) In the field of refrigeration, studies are categorized into three groups namely refrigeration cycle, refrigerant and modeling and control. In the category of refrigeration cycle, studies were focused on the enhancement or optimization of experimental or commercial systems including a R410a VRF(Various Refrigerant Flow) heat pump, a R134a 2-stage screw heat pump and a R134a double-heat source automotive air-conditioner system. In the category of refrigerant, studies were carried out for the application of alternative refrigerants or refrigeration technologies including $CO_2$ water heaters, a R1234yf automotive air-conditioner, a R436b water cooler and a thermoelectric refrigerator. In the category of modeling and control, theoretical and experimental studies were carried out to predict the performance of various thermal and control systems including the long-term energy analysis of a geo-thermal heat pump system coupled to cast-in-place energy piles, the dynamic simulation of a water heater-coupled hybrid heat pump and the numerical simulation of an integral optimum regulating controller for a system heat pump. (4) In building mechanical system research fields, twenty one studies were conducted to achieve effective design of the mechanical systems, and also to maximize the energy efficiency of buildings. The topics of the studies included heating and cooling, HVAC system, ventilation, and renewable energies in the buildings. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment is mostly focused on indoor environment and building energy. The main researches of indoor environment are related to infiltration, ventilation, leak flow and airtightness performance in residential building. The subjects of building energy are worked on energy saving, operation method and optimum operation of building energy systems. The remained studies are related to the special facility such as cleanroom, internet data center and biosafety laboratory. water supply and drain system, defining standard input variables of BIM (Building Information Modeling) for facility management system, estimating capability and providing operation guidelines of subway station as shelter for refuge and evaluation of pollutant emissions from furniture-like products.

• Food Science and Preservation
• /
• v.20 no.4
• /
• pp.573-582
• /
• 2013

This study was done in order to investigate the bioconversion of ginsenoside, as well as the quality characteristics of fermented ginseng, by using lactic acid bacteria. Quality characteristics such as the thin layer chromatography(TLC) pattern, ginsenosides, total phenolic content, electron donating ability, and total sugar of fermenting ginseng and red ginseng were analyzed. The ginsenoside Rg2r, Rh2s and Rh2r of the fermented ginseng and red ginseng for 65 hours at a temperature of $37^{\circ}C$ were not detected. The ginsenoside Rg1 and Re contents have decreased, while the Rh1, Rg2s, Rd, Rg3r, and Rg3s have increased due to fermentation. The ginsenoside Rg3 of the fermented red ginseng has increased and the contents were $114.83{\sim}131.68{\mu}g/mL$ (control $104.56{\mu}g/mL$). The total phenolic content and electron donating ability of the red ginseng have totally decreased after 7 days of fermentation. The total phenolic contents of the fermented ginseng and red ginseng with different lactic acid bacteria did not show any tendency as different strains. The electron donating ability of the fermented ginseng has increased; however, the electron donating ability of the red ginseng has decreased. The total sugars of the fermented ginseng and red ginseng with different lactic acid bacteria have also decreased.

• Korean Journal of Plant Resources
• /
• v.19 no.4
• /
• pp.491-496
• /
• 2006

Antimicrobial activity of 18 different traditional medicinal herbs extracts against Staphylococcus aureus was determined by a paper disc method. The Prunella vulgaris, Caesalpinia sappan and Rhus javanica extracts in 5 mg/ml, Poncirus trifoliata, Lonicera japonica and Seutellaria baicalensis extracts in 10 mg/ml and Schizandra chinensis, Alpinia katsumadai, Siegesbeckia orientalis extracts in 30 mg/ml showed a significant antimicrobial activity against Staphylococcus aureus. Minimum inhibitory concentrations of medicinal herbs extracts were in the range of $1{\sim}34\;mg/ml$ and $1{\sim}46\;mg/ml$, in the case of MeOH extracts and EtOH extracts, respectively. In addition, the antimicrobial activity of each solvent fraction was most significant with EtOAc layer. Optical density at 620nm after 24 hours incubation of Staphylococcus aureus in the presence of 100, 300 or 500 ppm of Caesalpinia sappan extract ranged from 0.02 to 0.03 compared to 0.4 in the absence of Caesalpinia sappan extract, indicating that growth of Staphylococcus aureus was significantly inhibited within 24 hours by the addition of at least 100 ppm of Caesalpinia sappan extract. Optical density at 620 nm after 24 hours incubation of Staphylococcus aureus in the presence of 300 ppm of Rhus javanica extract ranged from 0.02 to 0.03 compared to 0.4 in the absence of Rhus javanica extract, indicating that growth of Staphylococcus aureus was also significantly inhibited within 24 hours by the addition of at least 300 ppm of Rhus javanica extract. Optical density at 620 nm after 24 hours incubation of Staphylococcus aureus in the presence of 300 ppm of Seutellaria baicalensis extract ranged from 0.02 to 0.07 compared to 0.4 in the absence of Seutellaria baicalensis extract, indicating that growth of Staphylococcus aureus was also significantly inhibited within 24 hours by the addition of at least 300 ppm of Seutellaria baicalensis extract. In conclusion, these findings suggest that extracts from medicinal herbs may play important roles for antimicrobial activities against Staphylococcus aureus.

• Korean Journal of Environment and Ecology
• /
• v.10 no.1
• /
• pp.1-13
• /
• 1996

This study was conducted to investigate the avifauna and to suggest the management discipline for the protection of bird community in Odaesan National Park. Field survey was carried over 2 main trails by line transect method from mid June to early December in 1996. The 1st section included the area from Woljongas to Sangwonsa 7km distance. The 2nd section survey started from Sangwonsa via Bukdaesa and the summit of Odaesan to Sangwonsa 9.8 km distance. The study results were as follows ; The observed birds belonged to 9 orders 22families 52species, they also had Black Woodpecker(Dryocopus martius)designated as natural monument No. 242, Chinese Sparrow Hawk(Accipiter soloensis) and Kestrel(Falco tinnunculus) as natural munumet No. 323, Scops Owl(Out scops)and Korean Wood Owl(Strix aluco) as No. 324. These birds also were classified into 25 species for residents, 16 species for summer visitors, 8 species for passage migrants, 3 species for winter visitors, respectionely. The 2nd section showed a high species richness and individuals in every season, however, had a difference in species composition with 1st section. Nesting guild of breeding bird community used highly in order of bush, hole, and canopy as a nest resources. It is suggested that high bush-nesting guild had a deep relationship with bush layer located in the ecotone of 1st section and that located in the high elevated zone in 2nd section. Hole-nesting guild such as Black Woodpecker(Dryocopus martius), Gray-headed Woodpecker(Picus canus) and Great Spotted Woodpecker(Dendrocopos major) were surveyed only in 2nd section, so it could be attribute to the small fragmentation and the growing of high diameter at breast height(D.B.H) tree in 2nd section. It is urgent that the management of camping ground and people for the conservation of brook in 1nd section, trail protection for the prevention from trail enlargement in 2nd section for the bird protection. Artificial food in snowy winter will provide the good breeding condition with the residents and migrants. And, the endeavor to lessen the habitat fragmentation will be beneficial to the birds who have a large home range such as Black Woodpecker(Dryocopus martius) and Korean Wood Owl(Strix aluco). For the control of Domestic Dove(Columba livia) populations, it could be recommended that the elimination of their nesting resources by net.