• Journal of Environmental Science International
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• v.23 no.8
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• pp.1513-1522
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• 2014

Fish passage asssessments were conducted in the fishway at Juksan Weir, which was constructed as a four-major rivers project in the downstream area of Youngsan-River Watershed. For the research, fish-movements/migrations were analyzed for seven times from April ~ October, 2013 using an approach of fish trap-setting. Fish fauna and compositions were analyzed in the fishway, and seasonal- and diel-movement patterns were analyzed in relation to current velocity in the fishway. Also, abundances of exotic fishes such as bluegill sunfish (Lepomis macrochirus), large-mouth bass (Micropterus salmoides), and white curcian carp (Carassius cuvieri) were monitored in the fishway. Current velocity(n = 18) in the fishway showed large variations ($0.82{\pm}0.63m/s$) depending on the location of the fish trap-setting and this physical factor influenced the fish movements. Fish movements, based on the CPUE of individuals, in the fishway was greater in slower velocity (mean: 0.36 m/s, range: 0.10~1.54 m/s) than faster velocity (mean: 1.51 m/s, range: 0.90~1.90 m/s). Seasonal analysis of fish movements showed that most frequent uses (8 speices and 591 individuals, 66.2% of the total) of the fishway occurred in spring period(i.e., June). Diel movement analysis, in the mean time, showed highest in the time period of 00:00 ~ 3:00 am (7 species and 281 individuals, 20.9% of the total). The efficient managements in the fishway at Juksan Weir are required in relation to the hydrological regime.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.4
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• pp.701-712
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• 2012

The concept of $k$-shortest disjoint paths is considered important because the establishment of primary and backup forwarding paths exploiting shorter distance and faster propagation time is a dominant consideration for the design of a survivable backbone network. Therefore, we need to evaluate how well the concept of $k$-shortest disjoint paths is exploited for the design of a survivable ship backbone network considering the international standard related to ship backbone networks, the IEC61162-410 standard specifying how to manage redundant message transmissions among ship devices. Performance evaluations are conducted in terms of following objective goals: link capacity, hop and distance of primary and backup paths, even distribution of traffic flows, restoration time of backup forwarding paths, and physical network topology connectivity.

• Journal of Environmental Science International
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• v.13 no.4
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• pp.403-412
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• 2004

Waste water-soluble cutting oil was treated with WI type #1 and WI type #2. The properties of the original water-soluble cutting oil were pH=l0.4, viscosity=1.4cP, CODcr=44,750 ppm, and TOC=10,569 ppm. However, the properties of the oil used for more than 3 months were changed to pH=7.82, viscosity=2.1cP, CODcr=151,000 ppm, and TOC=74,556 ppm. It might be attributed to the fact that molecular chains were cut due to thermal oxidation and impurities such as metal chips were incorporated in to the oil during the operation processes. To prevent the putrefaction of oil, the sterilization effect of ozone and UV on the microorganism in the oil was investigated. Ozone treatment showed that 99.99% of the microorganism was annihilated with 30 minutes contact time and 60 minutes were necessary for the same effect when UV was used. Ozone treatment could cut molecular chains of the oil due to strong sterilization power, which was evidenced by the increase of TOC from 25,132 ppm at instantaneous contact to 28,888 ppm at 30 minutes contact time. However, UV treatment didn't show severe changes in TOC values and thus, seemed to cause of severe cut of molecular chains. When the activated carbon was used to treat the waste water-soluble cutting oil, TOC decreased to 25,417 ppm with 0.lg carbon and to 15,946 ppm with 5.0g carbon. This results indicated that the waste oil of small molecular chains could be eliminated by adsorption. From the results, it could be concluded that these treatment techniques could be proposed to remove the waste oil of small molecular chains resulting in the degradation of the oil properties. In addition, these experimental results could be used for the correlation with future works such as investigation of the molecular distribution according to the sizes, lengths, and molecular weight of the chains.

• International Journal of Concrete Structures and Materials
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• v.3 no.1
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• pp.3-9
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• 2009

This paper examines the incorporation of the crushed sand (CS) and desert sand (DS) in the formation of self compacting concrete (SCC). These sands have been substituted for the rolled sand (RS), which is currently the only sand used in concretes and which is likely to run out in our country. DS, which comes from the Tunisian Sahara in the south, is characterized by a tight distribution of grains size. CS, a by-product of careers containing a significant amount of fines up to 15%, is characterized by a spread out granulometry having a maximum diameter of around 5mm. These two sands are considered as aggregates for the SCC. This first part of the study consists in analyzing the influence of the type of sand on the parameters of composition of the SCC. These sands consist of several combinations of 3 sands (DS, CS and RS). The method of formulation of the adopted SCC is based on the filling of the granular void by the paste. The CS substitution to the RS made it possible, for all the proportions, to decrease the granular voids, to increase the compactness of the mixture and to decrease the water and adding fillers proportioning. These results were also obtained for a moderate substitution of DS/CS (< 40%) and a weak ratio of DS/RS (20%). For higher proportions, the addition of DS to CS or RS did not improve the physical characteristics of the SCC granular mixture.

• Journal of Environmental Science International
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• v.16 no.3
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• pp.377-383
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• 2007

In this study, the relationship between the pore size distribution and the adsorption amount of adsorbates is investigated in detail. Adsorption amounts of non-polar adsorbates were greater than those of polar adsorbates because of slight negative charge on surfaces of adsorbents. The adsorption of benzene on the surface of absorbents was largely influenced by the specific pore size of $2{\sim}4$ times of benzene diameter. But in case of toluene, the adsorption of toluene was affected by pore sizes of $2{\sim}4$ times as well as $4{\sim}6$ times of the diameter of toluene. Both acetone and MEK were examined by the same method. The adsorption of acetone was influenced by pore sizes of $2{\sim}4$ times of the diameter of acetone. But acetone does not look to be built up multi-layer on those pore sizes. Since acetone molecule is small and its mobility is so fast, it is assumed that the adsorption and desorption of acetone is simultaneously occurred at the same time even at room temperature. In case of MEK, MEK was effected by pore sizes of $2{\sim}4$ times of the diameter of MEK.

• The Journal of the Convergence on Culture Technology
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• v.7 no.1
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• pp.75-81
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• 2021

With the development of advanced information and communication technology, Generation Z, familiar with digital culture, is drawing keen attention as a major consumer of the fashion industry. In this study, casual wear for Generation Z, who is proficient in digital devices and prefers information acquisition and lifestyle over the Internet, was designed using 3D virtual simulation and developed into four looks: Gulish, Sportive, Easy and Contemporary. The use of simulation of 3D virtual clothing in costume design can build digitalization of future fashion industry through convergence with digital fashion design planning and production process in fandemic environment and strengthen online platform distribution. In a business environment that continues to innovate to enhance work efficiency by introducing an Untouch fashion production system, the use of 3D virtual clothing technology can increase the efficiency of sustainable management through 3D sample production, online fitting, modification, and final critic processes to reduce the time and cost of human and physical resources and review.

• International Journal of Advanced Culture Technology
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• v.9 no.4
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• pp.18-28
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• 2021

This study surveyed how retirees' evaluation of starting food service business affects the effectiveness their new business and quality of life, based on personal factors such as entrepreneurship and business-starting capability and environmental factors by using questionnaires. Bootstrapping was carried out in order to find out factors affecting rapidly changing new business environments and retirees' initial intent to start a business so as to verify basic hypothesis about relation between retirees' evaluation of starting food service business (social, economic, and psychological effects) and the effectiveness of their new business and quality of life and confirm whether the effectiveness of the new business acts as a medium between the evaluation of starting food service business and quality of life. In addition, PLS-MGA was performed in order to verify whether the correlations among test factors can be varied according to the kind of job the target retirees had. Having examined the basic thesis, it was found that social and economic factors had significant positive effect on the effectiveness of the new business, and social and psychological factors had significant positive effect on the quality of life. Having analyzed whether the effectiveness of new business acted as a media between evaluation of starting food service business and quality of life, there was no significant effect as a medium. Having studied whether the kind of job of the retirees controlled or affected the relations among evaluation of starting food service business, effectiveness of new business and quality of life, the results were as follows: in the office job retiree group, the greater economic factor led to increase of effectiveness of new business, while social and psychological factors influenced the quality of life; In the physical labor group, the higher social factor resulted in higher effectiveness of new business, which showed significant positive effect on the quality of life. Having researched about which element is considered to be most important in starting food service business, the most important element was found to be dish/menu, followed by staff management, accounting management, business management, and service education. Having analyzed relation between accomplishment and important consideration for starting food service business, "managers with entrepreneurship," "appropriate distribution of time to prepare for starting business," and "operation of practical field education programs" showed higher importance compared to the degree of satisfaction, so it is needed to more concentrate on the above matters. This study intends to raise retirees' awareness of starting business and help them live better life based on the analysis results, and further suggest detailed mechanism and specific operations of factors affecting retirees' decision making on starting business, such that they can use the information as basic materials to make better choices that can lead to successful business.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.21 no.1
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• pp.11-17
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• 2015

The increase of international and domestic trade according to global industrialization and economic growth has raised the national logistic cost in connection with physical distribution of articles. In order to reduce these costs and rise up national industrial competitiveness, Korea has also tried to improve the efficiency of logistics with various methods as advanced countries did. Especially, Korea government has decided standard dimension of pallets with T11 ($1100{\times}1100mm$) on the basis of unit load system in early 2000s, and certification program for logistics equipments has been operated to keep up the compatibility for the equipments and packaging with modulation of T11. Consequently, this certification program has contributed to extend standardization for logistics and to grow up 3 party logistics, but compared with advanced countries, the rate of national logistics cost to GDP (gross domestic product) still shows about 3% gap as demands for certification have been decreased in the recent. In this study, therefore, we proposed the development of logistics certification system based on social needs as a policy device to activate logistic industry as well as improve the efficiency of national logistics after we had analyzed all of certification programs for logistics being run in Korea. Namely, the first is the development of certification project for Northeast Asia's logistics corresponding to necessity for applying returnable transport system according to increasing the amount of trade between Northeast Asia's countries. The second is the development of certification project for safe transportation of packaging corresponding to costumer's needs for safe transit according to the growth of electronic commerce and the increase of global distribution.

• Journal of the Optical Society of Korea
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• v.14 no.3
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• pp.215-220
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• 2010

Aerosol observation with Raman LIDAR in NIES (National Institute for Environmental Studies, Japan) LIDAR network was conducted from 17 April to 12 June 2008 over Beijing, China. The aerosol optical properties derived from Raman LIDAR were compared with the retrieved data from sun photometer and sky radiometer observations in the Aerosol Robotic Network (AERONET). The comparison provided the complete knowledge of aerosol optical and physical properties in Beijing, especially in pollution and Asian dust events. The averaged aerosol optical depth (AOD) at 675 nm was 0.81 and the Angstrom exponent between 440 nm and 675 nm was 0.99 during experiment. The LIDAR derived AOD at 532 nm in the planetary boundary layer (PBL) was 0.48, which implied that half of the total AOD was contributed by the aerosol in PBL. The corresponding averaged LIDAR ratio and total depolarization ratio (TDR) were 48.5sr and 8.1%. The negative correlation between LIDAR ratio and TDR indicated the LIDAR ratio decreased with aerosol size because of the high TDR associated with nonspherical and large aerosols. The typical volume size distribution of the aerosol clearly demonstrated that the coarse mode radius located near 3 ${\mu}m$ in dust case, a bi-mode with fine particle centered at 0.2 ${\mu}m$ and coarse particle at 2 ${\mu}m$ was the characteristic size distribution in the pollution and clean cases. The different size distributions of aerosol resulted in its different optical properties. The retrieved LIDAR ratio and TDR were 41.1sr and 19.5% for a dust event, 53.8sr and 6.6% for a pollution event as well as 57.3sr and 7.2% for a clean event. In conjunction with the observed surface wind field near the LIDAR site, most of the pollution aerosols were produced locally or transported from the southeast of Beijing, whereas the dust aerosols associated with the clean air mass were transported by the northwesterly or southwesterly winds.

• The Journal of the Convergence on Culture Technology
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• v.6 no.3
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• pp.301-306
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• 2020

The vertical garden is an environment where plants have many limitations in their growth. In particular, the upper and lower parts of the foundation are characterized by unbalanced moisture distribution. And although it may vary depending on the installation location of the light, generally the base of the light is not in desperate need for plants to grow due to shade. The purpose of this study was to identify the physical characteristics of the vertical garden based on Felt through experiments, classify the location characteristics of the media, and suggest the method of installing the water quantity water frequency, and lighting according to the location characteristics of the foundation. As a result, it was found to be most appropriate to use a 4mm base for the vertical garden and to have an irrigation of about 10 minutes once every 6 hours. In addition, it was found that in order to create a light condition for sufficient growth of plants, light bulbs should be installed at the upper and lower parts of the foundation. As a result of irrigation and lighting tests, the results of the above-mentioned plants need to be referred to in selecting plants that are introduced to vertical gardens, as the results show that the upper part of the foundation has a lower moisture rate and a stronger light than the lower part, and the lower part has a higher moisture rate and a weaker light than the upper part. In the future, we would like to present more accurate methods of selecting and maintaining plants by conducting plant experiments using the underlying characteristics found in this study.