• Korean Journal of Microbiology
• /
• v.54 no.2
• /
• pp.105-112
• /
• 2018

To compare the denitrification efficiency, this study used molasses and methanol were used as external carbon sources. Specific experimental conditions were classified according to C/N ratio conditions. The batch test showed that the denitrification efficiency increased as C/N ratios of molasses and methanol rose. The most suitable C/N ratio of molasses turned out 4:1 considering the concentration of the residue chemical oxygen demand (COD) and the denitrification efficiency, which was 91.4%. Specific denitrification rate (SDNR) drawn as a kinetic factor demonstrated that molasses and methanol showed similar SDNR values as C/N ratios of molasses and methanol increased. Under the condition of C/N ratio 4:1, 0.0292 g $NO_3{^-}-N$ removal/g mixed liquor volatile suspended solid (MLVSS)/day (molasses), 0.0299 g $NO_3{^-}-N$ removal/g MLVSS/day (methanol) were found. Sludge adapted to molasses showed that Bacterium Pseudomonas sp. and Bergeylla sp. dominated through an analysis of microbial community. In addition, some bacteria were high convergences than the variety of microbial community. Accordingly, it was assumed that molasses focus on growing microorganisms specialized in denitrification and applied as a replaceable external carbon source that can enhance denitrification performance.

• Journal of Environmental Science International
• /
• v.2 no.2
• /
• pp.153-160
• /
• 1993

The problem of supply and transport of sediment from a mountainous catchment is very important in explaining dynamic geomorphology and the hydrological cycle. The discharge of suspended sediment is determined by a morphological system. Human interference to environment Is also an important, not negligible factor in sediment production. Moreover, growing concern in recent years for the problems of nonpoint pollution and for the transport of contaminants through terrestrial and aquatic ecosystems has highlighted the role of sediment-associated transport in fluvial systems. This study was conducted in forested and quarried catchments in order to clarify the different discharge process and the mechanism of suspended sediment dynamics for each catchment. As a forested catchment, the Yamaguchi River catchment which drains a $3.12km^2$ area was chosen. On the other hand, the Futagami River basin which is formed by three subbasins (1.07, 1.59 and $1.78km^2$), as a quarried catchment was selected. These catchments are situated to the north and east of Mt. Tsukuba, Ibaraki, Japan. The discharge pattern of suspended sediment from the Futagami River basin is more unstable and irregular than that from forested catchment, the Yamaguchi River catchment. Under the similar rainstorm conditions, suspended sediment concentration from quarried catchment during a rainstorm event increases from 43 to 27,340 mg/l. However, in the case of the forested catchment it changes only from nearly zero to 274 mg/l. Generally, the supply source of suspended sediment is classified into two areas, the in-channel and non-channel source areas. As a result of field measurements, in the case of the forested catchment the in-channel (channel bed, channel bank and channel margin) is the main source area of suspended sediment. On the other hand, remarkable sediment source area on the Quarried catchment is the non-channel that is unvegetated ground.

• Journal of KIISE:Information Networking
• /
• v.29 no.1
• /
• pp.24-30
• /
• 2002

Label switching technology is currently emerging as a solution for the rapidly growing of Internet traffic demand. Multiprotocol label switching(MPLS) is one of the standards made by the Internet Engineering Task Force(IETE) intended to enhance speed, scalability, and inter-opearability between label switching technologies. In MPLS, utilization of label space is a very important factor of network performance because labels are basic unit in packet switching. We propose a algorithm to effectively use label space by a multiple disconnect timer at the label switching router. Our algorithm is based on multiple utilization of the connection release timer over the MPLS network with multiple domains. In our algorithm, a relatively linger timeout interval is assigned to the traffic with higher class by the aid of the packet classifier. This reduces delay for making a new connection and also reduces the amount of packets which will be routed to the layer 3. Simulation results shows that reduction of required label number in MPLS network and this indicate our algorithm offers better performance than the existing ones in term of utilization of label space.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.8
• /
• pp.88-98
• /
• 2017

The purpose of this study is to investigate the effect of product selection of hospital workers cosmeceutical cosmetics on marketing communication among hospital workers who use cosmeceutical cosmetics that have emerged in line with the recent growing medical skin care field.Coping with complaints from consumers who buy cosmeceutical cosmetics in hospitals where cosmeceutical cosmetics are mainly used and sold, and minimizing the influence of negative issues will potentially strengthen consumer relationships. The study was conducted on 520 hospital workers who use cosmeceutical cosmetics in hospitals (dermatology, plastic surgery, women's clinic, and other hospitals) in Seoul, Gyeonggi and Incheon. A total of 502 questionnaires were used for the final analysis. The data analysis consisted of Cronbach's alpha, one-way ANOVA, exploratory factor analysis and Duncan test. Correlation analysis was performed to investigate the correlation between variables, and regression analysis was conducted to test hypotheses. The study results revealed that when choosing cosmetic cosmetics, marketing communication is influential. Especially, product value, quality, and price factors strongly affect marketing communication. This shows that we value the product and quality the most and we want a reasonable price. Considering this, we will pursue differentiated products only from cosmeceutical cosmetics and provide them as basic data necessary for securing potential customers and increasing the sales of cosmeceutical cosmetics in accordance with the changing trends.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.13 no.3
• /
• pp.109-114
• /
• 2011

A breeding population of Quercus glauca has been established via simple direct selection. Seedlings from naturally crossed seeds of 35 selected families growing in Jeju Island were placed using stroll repeated planting into two experimental forest located at Hannam and Sanghyo in Jeju. After 3 years of planting, characteristics of growth were examined. Growth pattern of trees in Sanghyo was better than those in Hannam. The average heights of filial were 66.8 cm in Hannam and 92.5 cm in Sanghyo. Root collar diameters of filial in Hannam and Sanghyo were 9.3 mm and 12.2 mm, respectively. A great weather differences especially in precipitation and temperature were shown between two test sites. The result of difference of growth pattern between two sites could be useful in provenance adaptability test. Data within families and individuals obtained from this study was also useful for establishment of seed orchard of Q. glauca.

• Informatization Policy
• /
• v.24 no.3
• /
• pp.27-41
• /
• 2017

With the growing interest in the 4th industrial revolution and big data, various policies are being developed for facilitating the use of public open big data, which are leading to a wide range of added values created from use of such data. Despite the expanded requirements for public data disclosure and the legal system improvement, however, the use of public open big data is still limited. According to the literature review, there are studies on policy proposals for the government guiding directions for public open big data, but there is a lack of studies that handle the issue from the users' viewpoint. Therefore, this study aims to analyze the public open data ecosystem in Korea and to analyze public open big data through interviews with the providers (the government and public institutions) and users (private sector companies and citizens). This way, the study finds inhibition factors and facilitation factors, draws out issues and suggests solutions through a causal relationship analysis between each factor. Being a research on finding measures for facilitating both public big data release and use, this study has theoretical implications. In the meanwhile, the derived issues and alternatives provide practical implications also for stakeholders who are planning to facilitate release and use of public open big data.

• Journal of Korea Water Resources Association
• /
• v.51 no.1
• /
• pp.35-48
• /
• 2018

Groynes are installed generally to protect the riverside or the river bank from the erosion caused by water flows by controlling the flow direction and velocity in rivers. In the past, groynes were used to secure enough depth of water in canals. As there has been a growing interest in river restoration and the natural river maintenance since 2000, groynes are proposed as a major environmental hydraulic structure because the flow control and various river bed conditions around the groyne can contribute to habitat functions. Groynes are typically installed in a series. In designing groyne series, groyne spacing is an important factor because the flow changes in the main canal and the flow inside the groyne area occurs variably depending on the groyne spacing. This study provide information to determine the groyne spacing suitable for the purpose of the groyne by examining the flows that variably changes according to the groyne spacing and angle in the recirculation zone of the groyne field. In particular, the formation of vortex, the location of vortex core and the water flow near the river bank, all of which occur in the recirculation zone inside the groyne area, were mainly analyzed to examine the flow characteristics near the river bank that influences the safety of the river bank area. The results of the experiment will serve as important basic data to examine changes in the river bed inside the groyne area as well as the safety of river banks following the installation of groyne series.

• Journal of the Korean Society for Library and Information Science
• /
• v.51 no.1
• /
• pp.175-199
• /
• 2017

Children's literature has a significant impact on children's intelligence and emotional development. The interest in children's literature is increasingly growing with the expectation of the award winning books and the educational values of children's books. Although the interest has brought about a quantitative increase in the domestic children's books, it has difficulty selecting high-quality children's books among various books. In such an environment, the Children's Literature Award will provide an authoritative source of choice, which will help guide the selection of quality books to those who want to read children's books. In addition to this trend, the library should check the status of winning works and incorporate them into new collection development policies. The purpose of this study is to present the direction of the library book development policy of the public library. For this purpose, 10 public libraries in Seoul, Korea were selected and analyzed quantitatively and qualitatively through the collection status of the children's literature winning books, loan status, turnover, Bonn's use Factor, and Trueswell's 80/20 rule. Based on the results of this analysis, we would like to suggest some issues to be reflected in library development policy of the future.

• Journal of Internet Computing and Services
• /
• v.17 no.6
• /
• pp.17-23
• /
• 2016

In the future network such as Internet of Things (IoT), the number of computing devices are expected to grow exponentially, and each of the things communicates with the others and acquires information by itself. Due to the growing interest in IoT applications, the broadcasting in Opportunistic ad-hoc networks such as Machine-to-Machine (M2M) is very important transmission strategy which allows fast data dissemination. In distributed networks for IoT, the energy efficiency of the nodes is a key factor in the network performance. In this paper, we propose a fuzzy logic based probabilistic multi-hop broadcast (FPMCAST) algorithm which statistically disseminates data accordingly to the remaining energy rate, the replication density rate of sending node, and the distance rate between sending and receiving nodes. In proposed FPMCAST, the inference engine is based the fuzzy rule base which is consists of 27 if-then rules. It maps input and output parameters to membership functions of input and output. The output of fuzzy system defines the fuzzy sets for rebroadcasting probability, and defuzzification is used to extract a numeric result from the fuzzy set. Here Center of Gravity (COG) method is used to defuzzify the fuzzy set. Then, the performance of FPMCAST is evaluated through a simulation study. From the simulation, we demonstrate that the proposed FPMCAST algorithm significantly outperforms flooding and gossiping algorithms. Specially, the FPMCAST algorithm has longer network lifetime because the residual energy of each node consumes evenly.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.9
• /
• pp.314-321
• /
• 2016

After the 1980s, as the economy was growing rapidly and the real estate market was active, a large increase in population was supplied to the city. Accordingly, the national apartment housing market is located in the form of Urban Housing Culture. On the other hand, with time, the supply apartment houses became superannuated and the residential environment became poor. Therefore, the environment of old apartment houses has been changed to improve by reconstruction. Despite this, reconstruction incurred not only a lot of construction waste, but also problems of environmental degradation, noise, traffic congestion, increasing number of households, and so on. Recently, the housing law has changed, and vertical extension remodeling focused on Small/Medium Town House is underway. This has been changed in response to the demand. This is one of essential parts in the remodeling field for the future, even though it has some problems in how uses existing buildings. Therefore, this study analyzed occurrence risk factor for each type through research materials and case analysis regarding the vertical extension remodeling of apartment housing. In addition, the relative importance was determined through questionnaires and interviews from constructors, designers, and experts in the field.