• Journal of Navigation and Port Research
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• v.42 no.4
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• pp.245-252
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• 2018

A method of transmitting an alert signal in case of man-overboard (MOB) systems in a small fishing vessel navigating within coastal area is being operated as VHF-DSC equipment via a distress alert button and V-P ass Equipment via alert button or beacon separation. However, a small fishing vessel with a couple of crews on board is an inappropriate way to alert a man-overboard condition. However, internationally, MOB equipment using VHF-DSC, AIS, and Bluetooth technologies is used to transmit alert signals directly to the mother ship and other radio stations. In order to analyze the performance and technology of the MOB equipment operating in foreign countries, it was confirmed that the alarm signal can be received within a maximum of one nautical mile when the MOB device is on the water surface. An MOB device that meets domestic conditions needs to send an alarm signal to a station within the VHF communication range. However, in order to reduce the false alert signal, it is most appropriate to operate the VHF-DSC radio equipment installed on the ship remotely. Analysis of various technologies connecting the MOB and the VHF-DSC revealed that the Bluetooth system has advantages such as device miniaturization. When an emergency signal is transmitted from the MOB device, it can be received by a dedicated receiver and recognized through an external input terminal of the VHF-DSC equipment generating its own alarm. If the emergency situation cannot be processed at the mother ship, a distress alert is sent to all radio stations via VHF-DSC for response under emergencies faced by small fishing vessels.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.375-375
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• 2010

CdTe as an absorber material is widely used in thin film solar cells with the heterostructure due to its almost ideal band gap energy of 1.45 eV, high photovoltaic conversion efficiency, low cost and stable performance. The deposition methods and preparation conditions for the fabrication of CdTe are very important for the achievement of high solar cell conversion efficiency. There are some rearranged reports about the deposition methods available for the preparation of CdTe thin films such as close spaced sublimation (CSS), physical vapor deposition (PVD), vacuum evaporation, vapor transport deposition (VTD), closed space vapor transport, electrodeposition, screen printing, spray pyrolysis, metalorganic chemical vapor deposition (MOCVD), and RF sputtering. The RF sputtering method for the preparation of CdTe thin films has important advantages in that the thin films can be prepared at low growth temperatures with large-area deposition suitable for mass-production. The authors reported that the optical and electrical properties of CdTe thin film were closely connected by the thickness-uniformity of the film in the previous study [1], which means that the better optical absorbance and the higher carrier concentration could be obtained in the better condition of thickness-uniformity for CdTe thin film. The thickness-uniformity could be controlled and improved by the some process parameters such as vacuum level and RF power in the sputtering process of CdTe thin films. However, there is a limitation to improve the thickness-uniformity only in the preparation process [1]. So it is necessary to introduce the external or additional method for improving the thickness-uniformity of CdTe thin film because the cell size of thin film solar cell will be enlarged. Therefore, the authors firstly applied the chemical mechanical polishing (CMP) process to improving the thickness-uniformity of CdTe thin films with a G&P POLI-450 CMP polisher [2]. CMP process is the most important process in semiconductor manufacturing processes in order to planarize the surface of the wafer even over 300 mm and to form the copper interconnects with damascene process. Some important CMP characteristics for CdTe were obtained including removal rate (RR), WIWNU%, RMS roughness, and peak-to-valley roughness [2]. With these important results, the CMP process for CdTe thin films was performed to improve the thickness-uniformity of the sputtering-deposited CdTe thin film which had the worst two thickness-uniformities of them. Some optical properties including optical transmittance and absorbance of the CdTe thin films were measured by using a UV-Visible spectrophotometer (Varian Techtron, Cary500scan) in the range of 400 - 800 nm. After CMP process, the thickness-uniformities became better than that of the best condition in the previous sputtering process of CdTe thin films. Consequently, the optical properties were directly affected by the thickness-uniformity of CdTe thin film. The absorbance of CdTe thin films was improved although the thickness of CdTe thin film was not changed.

• The Korean Journal of Air & Space Law and Policy
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• v.31 no.1
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• pp.3-36
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• 2016

Recently, the Supreme Court of Korea delivered a milestone judgment about air related multimodal transport. At there, the mattered cargo, some expensive jewellery, was transported from Qingdao, China to downtown office of consignee at Seoul via Incheon airport in Korea. As an air waybill was issued in this case, there was an air transport agreement between consignor and air courier operator. After arriving at Incheon airport, the shipment was transport by land arranged by the air courier operator, who was a defendant in this case. Upon arriving at the final destination, it was found that the jewellery was lost partly and based on circumstantial evidence, the damage presumed to be occurred during the land transport. As a subrogee, the insurance company who paid for consignee filed an action against the air courier operator for damage compensation. Defendant contended that Montreal convention should be applicable in this case mainly for limited liability. The lower court of this case confirmed that applying the limited liability clause under Montreal Convention is improper under the reason that the damage in this case was or presumed to be occurred during surface transport. It was focused on the Montreal Convention article 18 which says that the period of the carriage by air does not extend to any carriage by land, by sea or by inland waterway performed outside an airport. However, the Supreme Court overturned the lower court's decision. The delivered opinion is that the terms of condition on the air waybill including limited liability clause should be prevailed in this case. It seems that the final judgment was considered the fact that the only contract made in this case was about air transport. This article is for analysis the above decisions from the perspective that it is distinguishable between a pure multimodal transport and an expanded air transport. The main idea of this article is that under the expanded air transport, any carriage by land, sea or inland waterway only for the performance of a contract for carriage by air, for the purpose of loading, delivery or transhipment is still within the scop of air transport.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.1
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• pp.57-64
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• 2011

Purpose: The purpose of this study was to compare the cleansing performance of a distilled water, a diluted solution of sodium hypochlorite as a household bleaching cleanser and three alkaline peroxide cleansers in vivo plaque deposits by using scanning electron microscope. Materials and methods: Five individuals were selected from department of the prosthodontics in Pusan National University Hospital, and each of them was inserted with specimens for plaque accumulation in their temporary dentures for 48 hours. The specimens were removed and cleaned by each cleansing agents for 8 hours. Scanning electron micrographs were made from the specimens at a magnification of ${\times}2,000$. A panel of ten persons with a dental or paradental background, but not directly involved in the study, was selected to analyze the photomicrographs to determine which denture cleanser was more effective in removing plaque. Results: Diluted solution of sodium hypochlorite was the most effective at removing plaque following $Polident^{(R)}$, $Cleadent^{(R)}e$, $Bonyplus^{(R)}$ and distilled water in order. But there was no significant difference of cleansing efficacy between diluted solution of sodium hypochlorite and $Polident^{(R)}$, $Polident^{(R)}$ and $Cleadent^{(R)}e$, $Cleadent^{(R)}e$ and $Bonyplus^{(R)}$, respectively (P > .05). Alkaline peroxide cleansers by themselves cannot adequately remove accumulated plaque deposits, especially if the deposits are heavy. Corrosion could be seen on the surface of non-precious alloy specimens immersed in diluted solution of sodium hypochlorite. Conclusion: It is recommended to use of alkaline peroxide type cleansers with brushing whenever possible, since denture cleanliness is often poor due to the relative inefficiency of these cleansers.

• Food Science of Animal Resources
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• v.23 no.1
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• pp.9-15
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• 2003

All diets were based on feeds of fattening period pigs(LY x D, ca. 90 kg) with six treatments, which were the control, containing 5% beef tallow(C), 3% beef tallows and 2% perilla seeds oil(T1), 250 ppm vit. E(${\alpha}$-tocopheryl acetate) in T1(T2), 3% beef tallow and 2% squid viscera oil(T3), 250 ppm vit. E in T3(T4), and 3% beef tallow and 2% CLA(T5), respectively. Produced porks and their carcass characteristics were as follows. The daily gain of pigs was higher in T2 and 73 than any other treatments(p<0.05). Its T2 and T3 was 3.71 and 3.80 respectively, however, there was no significance in feed intake. The highest back fat thickness was shown in control group on market weight, while there was no significant difference on their initial weight. Loin-eye muscle area did not show any significant difference on initial weight and on market weight, however, its T5 was about twice as large as T2's. Content of triglyceride in blood was high in control group as compared to others; especially, the values for T3, T4 and T5 were significantly low(p <0.05). There was no significant difference in total cholesterol contents, and the ratio of HDL cholesterol/total cholesterol was higher in vit. E treated samples than untreated sample. Atherogenic index was high in sample with T3 and low in sample with T2. The perilla seed oil, squid fish oil, and vit. E decreased atherogenic index. Dressing percentage, back fat thickness, and grade did not show any significant difference(p >0.05); however, T2, C and T3, T1 and T5 showed 4.67, 4.29, 4.00 respectively, in grades.

• Geophysics and Geophysical Exploration
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• v.19 no.1
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• pp.1-10
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• 2016

The hypocenter distribution of microseismic events generated by hydraulic fracturing for shale gas development provides essential information for understanding characteristics of fracture network. In this study, we evaluate how inaccurate velocity models influence the inversion results of two widely used location programs, hypoellipse and hypoDD, which are developed based on an iterative linear inversion. We assume that 98 stations are densely located inside the circle with a radius of 4 km and 5 artificial hypocenter sets (S0 ~ S4) are located from the center of the network to the south with 1 km interval. Each hypocenter set contains 25 events placed on the plane. To quantify accuracies of the inversion results, we defined 6 parameters: difference between average hypocenters of assumed and inverted locations, $d_1$; ratio of assumed and inverted areas estimated by hypocenters, r; difference between dip of the reference plane and the best fitting plane for determined hypocenters, ${\theta}$; difference between strike of the reference plane and the best fitting plane for determined hypocenters, ${\phi}$; root-mean-square distance between hypocenters and the best fitting plane, $d_2$; root-mean-square error in horizontal direction on the best fitting plane, $d_3$. Synthetic travel times are calculated for the reference model having 1D layered structure and the inaccurate velocity model for the inversion is constructed by using normal distribution with standard deviations of 0.1, 0.2, and 0.3 km/s, respectively, with respect to the reference model. The parameters $d_1$, r, ${\theta}$, and $d_2$ show positive correlation with the level of velocity perturbations, but the others are not sensitive to the perturbations except S4, which is located at the outer boundary of the network. In cases of S0, S1, S2, and S3, hypoellipse and hypoDD provide similar results for $d_1$. However, for other parameters, hypoDD shows much better results and errors of locations can be reduced by about several meters regardless of the level of perturbations. In light of the purpose to understand the characteristics of hydraulic fracturing, $1{\sigma}$ error of velocity structure should be under 0.2 km/s in hypoellipse and 0.3 km/s in hypoDD.

• Ecology and Resilient Infrastructure
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• v.7 no.3
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• pp.208-217
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• 2020

A biopolymer based on microorganism-derived β-glucan and xanthan gum is being studied as a new eco-friendly material that stabilizes the riverbank slope, and also promotes vegetation growth. However, it is still inconclusive whether biopolymers have a positive effect on plant performance in the riverbanks which are subjected to various climatic factors and plant competitions. For a practical ecological evaluation of the biopolymers, their effect on plant growth promotion was studied in a natural environment. Considering the relationship between competition and plant community formation, the effects of biopolymers on competition were also investigated. For four plant species (Echinochloa crus-galli, Pennisetum alopecuroides, Leonurus japonicus, and Coreopsis lanceolata), the biopolymer effects under intra/interspecific competition were tested at the riverbank (20 m × 10 m) near Samjigyo Bridge in Damyang-gun, Jeollanam-do. A biopolymer powder was mixed with water and commercial soil following the manufacturer's recommendations. The soil mixed with the biopolymer was filled in a pot or applied to the surface of the commercial soil with a thickness of 3 cm. Across the competition treatments, the biopolymer treatment promoted root growth of the target plant species and decreased the specific leaf area. The total biomass and shoot dry weight of P. alopecuroides increased in response to the biopolymer treatment. The competition treatment decreased the total biomass and shoot dry weight compared to the case without competition. Notably, such a competitive effect was similar in all the biopolymer treatments. Thus, biopolymers, when mixed with soil, promote the growth of some plant species, but do not appear to affect the competitive ability of plants.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.4
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• pp.404-411
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• 2007

Adsorption performance of odorous compounds such as geosmin and 2-MIB on granular activated carbon were evaluated in this study. The coal-based activated carbon was found more effective than other carbons in adsorption of geosmin and 2-MIB. The wood-based virgin activated carbon was less effective than coconut- and coal-based carbon in adsorption nevertheless having larger pore volume and specific surface area than others carbons. The maximum adsorption capacity(X/M) of coal-based activated carbon for geosmin and 2-MIB was $1.2\sim1.9$ and $2.1\sim2.6$ times larger than coconut- and wood-based virgin activated carbon, respectively. Carbon usage rate (CUR) of coal-, coconut- and wood-based virgin activated carbons for geosmin and 2-MIB were 1.72 and 1.44 g/day, 1.72 and 2.05 g/day and 2.12 and 1.90 g/day, respectively. In the evaluation of adsorption isotherm of geosmin and 2-MIB for coal-, coconut- and wood-based virgin activated carbons, k value of 2-MIB was lower than geosmin, It menas 2-MIB is more difficult to remove by activated carbon adsorption than geosmin. The relationship of max. adsorption versus total pore volume of coconut- and wood-based virgin and used activated carbon for geosmin and 2-MIB were $y=264,459\times-79,047(R^2=0.95)$, $y=319,650\times-101,762(R^2=0.93)$.

• Journal of Animal Science and Technology
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• v.53 no.1
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• pp.51-57
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• 2011

The performance of grass filter strips (GFS) in abating $NO_3$-N concentrations from the forage cropland was tested in an experiment on the 10% slope in Grassland and Forages Division, National Institute of Animal Science, Rural Development Administration (RDA) from October 2007 to September 2009. Forage croplands with rye-corn double cropping system applied with chemical fertilizer and livestock manure (LM) were compared in a natural condition. The plots were hydrologically isolated in a randomized block layout of 3 treatments $\times$ 2 factors $\times$ 3 replicates. Main plots consisted of the length of GFS, such as 0 m, 5 m, 10m and 15m. Sub plots consisted of the type of LM, such as chemical fertilizer (CF), cattle manure (CM) and swine manure (SM). Dry matter yields of rye and corn increased significantly in order of CF > CM > SM (p<0.05). Concentrations of $NO_3$-N in surface runoff water were reduced as the length of GFS increased. Especially, GFS with 10 m and 15m reduced $NO_3$-N concentrations significantly compared to that with 0 m and 5 m (p<0.05). The results from this study suggest that GFS improved the removal and trapping of manure nutrients from forage croplands.

• Journal of The Korean Society of Grassland and Forage Science
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• v.7 no.1
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• pp.63-69
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• 1987

This field experiment was undertaken to assess the effectiveness of magnesium- and boronenriched complex fertilizer ($N-P_2O_5-K_2O-MgO-B_2O_3$ : 8-25-7-3-0.2) compared with some straight fertilizers on the hilly pasture establishment. This second part was concerned with the changes in the forage yields, yield components, botanical and chemical compositions in a mixed grassclover sward (orchardgrass, tall fescue, Kentucky bluegrass, and ladino clover). The results from a two-year experiment are summarized as follows: 1. Dry matter yields of whole mixed forages were significantly reduced in control by 54.5% and the NK-plot ($P_o$ by 35.0%, compared with the normal NPK-plots. 2. The yields of oversown grasses were significantly reduced in control by 79.7% and the NKplot ($P_o$) by 52.196, compared with the normal NPK applications. At the normal NPK applications, the oversown grasses were lowest in the yields when provided with double superphosphate with no significant differences. The yields of weeds were not significantly influenced by the treatments. 3. The significant differences in the legume yields (relative yield, %) were laid in the follow. ing increasing order; complex fertilizer (178.5%) > NPK-fused superphosphate (139.5%) > NPK-double superphosphate (100.0%) = control > NK (51.1%). The legume yield was much more depressed in the NK-plot ($P_o$) than in control ($N_oP_oK_o$). 4. The rate of oversown grasses and whole forages were increased by the normal NPK applications, showing little difference among the kinds of fertilizers. It was recognized that the application of complex fertilizer contributed to the increasing of legume rate in the mixed sward. This contribution turned out to be due to the rather enhanced performance and yield-increase of legume, compared with the straight fertilizers. 5. With the NK-treatment ($P_o$) the P concentration in mixed forages dropped below the critical level (0.2%). The Mg concentrations in mixed forages were lower in all the plots than the critical level (0.2%). Therefore, a sufficient amount of Mg was desirably to be applied It is recommended that, in relation to its effectiveness and simplification of fertilizer application, the application of this complex fertilizer for pasture establishment be carried out. The change of the constituent ratio of complex fertilizer to the standard of "8 - 15-20 - 7 - 5-10 - 0.2" considering the need of sufficient Mg supply and the continuous accumulation of P in the top-surface soil is possibly recommended.commended.