• 한국해양학회지
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• v.24 no.4
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• pp.165-171
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• 1989

To examine the sample variability of zooplankton, samples were collected at two stations in the nearshore off Anhung (Chungnam, Korea), using a NORPAC net (76 Cm diameter, 0.333 mm mesh size) for two days, April 5 and 6, 1989. The net was towed vertically to eliminate the source of variation due to vertical migration. During the period of 6 hours, triplicate sampling was done every one or two hour at each station. Species composition and abundances at two stations were not so different, but the abundances at each station varied greatly with respect to sampling time. Greater abundance at one sampling time ranged 2.3-8.7 times of smaller abundance at another sampling time. At the level of ${\alpha}=0.05$, however, mean abundances of different sampling time did not differ significantly from each other due to the large variance. It was believed that the large variance was caused by the time dependent effect of patchiness of which parameters were varied with time because of sea water movement. From the variation within the triplicate samples, it was considered that the abundance data obtained from single tow were not significantly different from the data in the range of 50-200% of those from single tow. From these results, the necessity for the replicate and time dependent sampling was indicated. In the nearshore like the sampling site of this study, it seemed to be better to reduce the number of stations for the replicate and time dependent sampling though the proper sampling scheme was to be decided based on the goal of the study.

• Journal of the Korean Institute of Gas
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• v.23 no.2
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• pp.74-81
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• 2019

Expansion turbine system to recover the electricity energy from natural gas transmission stations is a well-known technique. The turbo-expander efficiency depends on the ratio of the natural gas flow rates to the design flow rate of the turbo-expander. However, if there is a big difference of the natural gas flow rate through the pressure letdown station because of seasonal supply pattern, that is, high flow rate in winter while low flow rate in summer, single turbo-expander system is not so efficient as to recover the pressurized energy from the low flow-rate natural gas. Therefore, we have proposed a new concept of double turbo-expander system: one is a big capacity and the other a small capacity. Here we have theoretically computed the electric powers at the pressure reduction from 18.5 bar to 7.5 bar depending on the inlet conditions of temperature and flow rate. The calculated electricity generation has been increased by 30% from 12.4 MW in a single turbo expander to 16.1 MW in the proposed double turbo-expander system when a minimal design efficiency of 0.72 is applied.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.7
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• pp.949-955
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• 2019

Objective: The present study was to investigate the association of polymorphisms in exon-9 of the bone morphogenetic protein receptor-1B (BMPR-1B) gene (C864T) with litter size in 240 Dorset, 232 Mongolian, and 124 Small Tail Han ewes. Methods: Blood samples were collected from 596 ewes and genomic DNA was extracted using the phenol: chloroform extraction method. The 304-bp amplified polymerase chain reaction product was analyzed for polymorphism by single-strand conformation polymorphism method. The genotypic frequency and allele frequency of BMPR-1B gene exon-9 were computed after sequence alignment. The ${\chi}^2$ independence test was used to analyze the association of genotypic frequency and litter size traits with in each ewe breed, where the phenotype was directly treated as category. Results: The results indicated two different banding patterns AA and AB for this fragment, with the most frequent genotype and allele of AA and A. Calculated Chi-square test for BMPR-1B gene exon-9 was found to be more than that of p value at the 5% level of significance, indicating that the population under study was in Hardy-Weinberg equilibrium for all ewes. The ${\chi}^2$ independence test analyses indicated litter size differences between genotypes was not the same for each breed. The 304-bp nucleotide sequence was subjected to BLAST analysis, and the C864T mutation significantly affected litter size in singletons, twins and multiples. The heterozygosity in exon-9 of BMPR-1B gene could increase litter size for all the studied ewes. Conclusion: Consequently, it appears that the polymorphism BMPR-1B gene exon-9 detected in this study may have potential use in marker assisted selection for litter size in Dorset, Mongolian, and Small Tail Han ewes.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.06a
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• pp.107-108
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• 2014

As the demand for precise navigation has increased, more focus is put on the precise positioning, RTK(Real Time Kinematics) which has been used in the surveying field. The Position of Single Reference Station RTK or two-way network RTK such as VRS (Virtual Reference Station) is accurate enough to be used as a main technology in land surveying, however its service area and number of users is limited and the users are assumed static. This characteristic is not suitable to the navigation, whose service target is infinite number of users moving over a wide area. One-way network RTK has recently been suggested as a solution for the precise navigation technique for the mobile user. This paper shows the performance prediction of the one-way network RTK such as MAC(Master-Auxiliary Concept), or FKP (Flachenkorrekturparameter). To show the performance variation by the rover position, we constructed a simulation data of users on the grid with 0.1 degree spacing between 36.5 and 37 degree latitude and between 127 and 127.5 degree longitude.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.3
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• pp.199-212
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• 1998

The ultimate goal of this study can be summed up as follows: First, the utility of Time-Lapse that observes and records people's behavior will be shown and its merits and demerits will be discussed through comparing with other data-collecting methods such as the naked- eye observation, and the specific way in which Time-Lapse can be put to use will be suggested. Second, analysis of use behavior boserved in the plaza of Chungryangri station by Time-Lapse will be made, on the basis of which suggestions will be made concerning planing, designing, layout, and management of the station plaza. Time-Lapse can observe and records the plaza of Chungryangri Staton through 6 different ways of recording in Time-Lapse: 30 seconds, every minute, every two minutes, second every five minutes, every one tenth of a second, and every one fifth of a second, and these different ways of recording were analyzed through comparison from one to each other to check their respective utilities. And also analysis of tracks of pedestrians, density, and use behavior of users were made, according to which the way in which Time-Lapse can be utilized was examined. Several useful results obtained from this study are shown as follows. First, Time-Lapse made it possible to continuously observe for a long time using minimu efforts, and a single tape which is able to cover from 12 hours up to 25 days is useful for observing variation of behavior in space with the passage of time and seasons. Second, among six ways of recording, the recording every one tenth of a second and every one fifth of a second are useful for finding the tracks of pedestrians, the number of users, the member compositions, the time spent in one place, and manner of use. And besides the moving direction and its purpose can be recognized in a short time, which makes it possile to see where crossings of moving directions occur. Third, the recording every thirty seconds, every minute, every two minutes, and every five minutes are useful for analyzing the density in space as well as for finding the number of users and frequency of facilities use. In particular the recording every thirty seconds made it possible to keep the track of pedestrians' walking, and to observe even slowly moving motions such as cleaning. But when the recording interval exceeds one minute, this was not possible. Fourth, time-lapse has advantages over the naked eye observation in several respects. Time-lapse can measure observed behavior and density in terms of number, and locate the position of users. Time-Lapse, if accompanied by other methods such as interviewing and question that can examine psychological aspects like satisfaction or the purpose of use and be a useful device for space studies.

• Korean Journal of Breeding Science
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• v.41 no.2
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• pp.154-157
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• 2009

Pear has a gametophytic self-incompatibility (SI) system and its SI reaction is controlled by a single multi-allelic S-locus. 'Wonkyo Na-jasoojung 2' was selected from a cross between 'Wonwhang', early season major pear cultivar with high fruit quality and self-incompatible, and 92-18-79 (${S_4}^{sm}{S_4}^{sm}$) obtained from self cross of 'Osa-nijisseiki' (${S_2S_4}^{sm}$) (SM, stylar-part mutant), self-compatible bud mutant that originated from self-incompatible 'Nijisseiki' ($S_2S_4$) made in 2001 at the National Institute of Horticultural and Herbal Science, Rural Development Administration in Korea. '92-18-79' was selected as a self-compatible source through field investigation. It bloomed 1 day earlier than 'Osa-Nijisseiki' and similar to 'Wonwhang' in 2008. It is medium in tree vigor and spreading in tree habit. 'Wonkyo Na-jasoojung 2' is classified as highly susceptible to pear scab (Venturia nashicola) similar to 'Osa-Nijisseiki' and as resistant to black spot (Alternaria kikuchiana) similar to 'Wonwhang'. It had 65.7% fruiting rate by self pollination. The average optimum harvest time of 'Wonkyo Na-jasoojung 2' was 148 days after full bloom and it matured 2 days earlier than 'Osa-Nijisseiki' and 11 days later than 'Wonwhang'. The fruit is roundish oblate in shape and yellowish brown in skin color. Average fruit weight was 445 g and soluble solids content was 13.3 $^{\circ}Brix$. The flesh had abundant juice and negligible grit.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.2
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• pp.64-79
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• 2023

This study reviewed the process of applying the Monte Carlo simulation technique to the traffic allocation problem of metropolitan subways. The analysis applied the assumption of a normal distribution in which the travel time information of the inter-station sample is the basis of the probit model. From this, the average and standard deviation are calculated by separating the traffic between stations. A plan was proposed to apply the simulation with the weights of the in-vehicle time of individual links and the walking and dispatch interval of transfer. Long-distance traffic with a low number of samples of 50 or fewer was evaluated as a way to analyze the characteristics of similar traffic. The research results were reviewed in two directions by applying them to the Seoul Metropolitan Subway Network. The travel time between single stations on the Seolleung-Seongsu route was verified by applying random sampling to the in-vehicle time and transfer time. The assumption of a normal distribution was accepted for sample sizes of more than 50 stations according to the inter-station traffic sample of the entire Seoul Metropolitan Subway. For long-distance traffic with samples numbering less than 50, the minimum distance between stations was 122Km. Therefore, it was judged that the sample deviation equality was achieved and the inter-station mean and standard deviation of the transport card data for stations at this distance could be applied.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.8A
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• pp.1096-1103
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• 2000

The default server strategy is commonly used for location and state managements of mobile host in mobile computing. With this strategy, we can find the cell of destination mobile host to send data by querying the default server. In SDN(single Default Notification) strategy which is a kind of default server strategy, the call is established after the location and state of the callee is acquired to the query server by querying the default server. But the communication cost overhead from the default server is increased if there are large number of cells and query requests, and if it is too far from the default server to a base station. Still more it will be unable to establish any calls to a mobile host when there is a fault in the default server of this host. In this paper, we suggest add evaluate a default server replication strategy to reduce the communication cost overhead and to make the service available.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.1
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• pp.26-33
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• 2003

The SSB(Single Side Band) communication in the 27MHz band has mainly been using between fishiery station and small fishing ship less than 101ons, but the most of small fishing ship are depend on cellular system. When accident for small ship at sea happens, It's very important to communicate continuously for preventing the collision and taking action. At present it is hard to control small fishing ship and provide information properly by using 27MHz SSB channel. Therefore in this paper We present TRS communication system applied for small fishing ship to protect the safety and life at sea and to prepare for emmergency, and also validate it's application.

• Journal of Cadastre & Land InformatiX
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• v.45 no.2
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• pp.45-56
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• 2015

The main purpose of this investigation is to make up for the limitations of parcel addressing and to seek the application plan of cadastral triangulation point to effective installation of national index numbers. The test-bed has been constructed at the mountainous area located in Nowon-gu, seven cadastral triangulation points within the test-bed was directly applied to this investigation. Each points have been firstly converted from a plane rectangular coordinates to a single plane rectangular coordinates (UTM-K). To verify positioning results achieved from these points, a single plane rectangular coordinates through the Network-RTK was considered. With regards to verification result, maximum coordinate shift was revealed by 6 cm, this level of difference can be satisfied to Article 7, paragraph 2 "the regulation for National Index Number". This means that coordinate transformation applied with cadastral triangulation points can achieve the sastisfied result without local surveying. And also, remarkable effects have been created in terms of financial effectiveness and safe preservation of cadastral triangulation points due to the omission of local surveying.