• Asian-Australasian Journal of Animal Sciences
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• v.25 no.3
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• pp.299-303
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• 2012

Inbreeding is the mating of relatives that produce progeny having more homozygous alleles than non-inbred animals. Inbreeding increases numbers of recessive alleles, which is often associated with decreased performance known as inbreeding depression. The magnitude of inbreeding depression depends on the level of inbreeding in the animal. Level of inbreeding is expressed by the inbreeding coefficient. One breeding goal in livestock is uniform productivity while maintaining acceptable inbreeding levels, especially keeping inbreeding less than 20%. However, in closed herds without the introduction of new genetic sources high levels of inbreeding over time are unavoidable. One method that increases selection response and minimizes inbreeding is selection of individuals by weighting estimated breeding values with average relationships among individuals. Optimum genetic contribution theory (OGC) uses relationships among individuals as weighting factors. The algorithm is as follows: i) Identify the individual having the best EBV; ii) Calculate average relationships ($\bar{r_j}$) between selected and candidates; iii) Select the individual having the best EBV adjusted for average relationships using the weighting factor k, $EBV^*=EBV_j(1-k\bar{{r}_j})$ Repeat process until the number of individuals selected equals number required. The objective of this study was to compare simulated results based on OGC selection under different conditions over 30 generations. Individuals (n = 110) were generated for the base population with pseudo random numbers of N~ (0, 3), ten were assumed male, and the remainder female. Each male was mated to ten females, and every female was assumed to have 5 progeny resulting in 500 individuals in the following generation. Results showed the OGC algorithm effectively controlled inbreeding and maintained consistent increases in selection response. Difference in breeding values between selection with OGC algorithm and by EBV only was 8%, however, rate of inbreeding was controlled by 47% after 20 generation. These results indicate that the OGC algorithm can be used effectively in long-term selection programs.

• Journal of the Society of Naval Architects of Korea
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• v.53 no.5
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• pp.371-379
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• 2016

In the ship design process, ship motion and propulsion performance in sea waves became very important issues. Especially, prediction of ship propulsion performance during real operation is an important challenge to ship owners for economic operation in terms of fuel consumption and route-time evaluation. Therefore, it should be considered in the early design stages of the ship. It is thought that the averaged value and fluctuation of effective inflow velocity to the propeller have a great effect on the propulsion performance in waves. However, even for the nominal velocity distribution, very few results have been presented due to some technical difficulties in experiments. In this study, flow measurements near the propeller plane using a stereo PIV system were performed. Phase-averaged flow fields on the propeller plane of a KVLCC2 model ship in waves were measured in the towing tank by using the stereo PIV system and a phase synchronizer with heave motion. The experiment was carried out at fully loaded condition with making surge, heave and pitch motions free at a forward speed corresponding to Fr=0.142 (Re=2.55×106) in various head waves and calm water condition. The phase averaged nominal velocity fields obtained from the measurements are discussed with respect to effects of wave orbital velocity and ship motion. The low velocity region is affected by pressure gradient and ship motion.

• Journal of Agricultural Extension & Community Development
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• v.17 no.3
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• pp.527-548
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• 2010

The objective of this study is to suggest the developmental tasks for the successful fostering the Farmer's Study Group which have been guided by the agricultural extension work since 1994 in Korea. The 3,278 farmers study groups with 148,420 memberships have been organized in field of grains, cash crop, horticulture, livestock, improving living conditions, food processing and so on. Although the number of study groups have rapidly expanded, there also are tasks to be secured for their successful development in terms of (a) desirable phase of the study groups and goals of its fostering, (b) managements / administration of them, (c) long-term tasks to be reviewed. With regard to the desirable phase of the study groups and goals of its fostering, they should secure differential mission and the way of works compare to the other farmer's groups. Also, there should be consensus on the proper number of study groups to be fostered with a agricultural technical center at local level. With regard to the managements / administration of the study groups, there should be the different support, assistance and guidance according to the developmental level of the groups. For these, there should be evaluation works on the groups, and guidance manuals for the extension workers. Also extension works should facilitate the establishment of networks among groups over the counties. Finally, to establish the nationwide association in hierarchy and to make the cooperative works with similar farmer's group, doing the value-added activities rather than mere information exchange, and the introduction of capacity building programs for the extension workers are long-term tasks needed to review for the successful fostering study groups.

• Korean Journal of Construction Engineering and Management
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• v.5 no.2 s.18
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• pp.115-122
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• 2004

This study identifies various risk factors associated with activities of early construction stage, then establishes the Risk Breakdown Structure(RBS) by classifying the risks into the three groups; Common risks, risks for Earth works, and risks for Foundation works. The Common risks are identified and classified by considering various aspects of the early construction stage such as financial, political, constructional aspects, etc. The risks for Earth works and Foundation works are identified in detail by surveying technical specifications, relevant claim cases and interviewing with experts. These risks are classified based on the Wok Breakdown Structure(WBS) of the early construction stage. The WBS presented in this study classifies the works of early construction stage into four categories; excavation, sheeting works, foundation works, footing works. This study suggests a risk analysis method using fuzzy theory for construction projects. Construction risks are generally evaluated as vague linguistic value by subjective decision making. Fuzzy theory is a proper method to quantify vague conditions of construction activities. Therefore, this study utilizes fuzzy theory to analyse construction risks. The weight of risks is estimated by reflecting the interrelationship among risk factors from absolute weights obtained by fuzzy measure into the relative weights by Analytical Hierarchy Process(AHP). The interrelationship is estimated by Sugeno-fuzzy measure.

• Journal of the Korean Geosynthetics Society
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• v.5 no.4
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• pp.27-33
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• 2006

Frictional properties between geostrip and sand paper interface were estimated considering soil particle size also the friction coefficients and angles were determined with normal stress. Three kinds of geostrips of design strength 50, 70, 100 KN/m were used and 5 sandpapers of P100, P220, P320, P400, P600 were used also. Shear strength between geostrip and sand paper interface with design strength showed big difference and this is due to the uniform surface pattern of each geostrip when contact to sandpaper without regard to design strength. Shear strength of geostrip was increased with design strength and geostrips/P100 sandpaper interface showed the biggest value. Finally, all of geostrips showed the decrease phenomena of post-peak strength and this is due to the abrasion of geostrip surface by shear test.

• Journal of Magnetics
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• v.18 no.3
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• pp.342-347
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• 2013

Local wall thinning in pipelines affects the structural integrity of industries, such as nuclear power plants (NPPs). In the present study, a development of pulsed eddy current (PEC) technology that detects the wall thinning of pipelines covered with insulation is reviewed. The methods and experimental results, which have two kinds of probe with a single and double core, were compared. For this purpose, the single and double core probes having one and two excitation coils have been devised, and the differential probe with two Hall sensors has been fabricated to measure the wall thinning in insulated pipelines. The test sample is a stainless steel having different thickness, laminated by plastic insulation to simulate the pipelines in NPPs. The excitation coils in the probe is driven by a rectangular current pulse, the difference of two Hall sensors has been measured as a resultant PEC signal. The peak value of the detected signal is used to describe the wall thinning. The double core probe has better performance to detect the wall thinning covered with insulation; the single core probe can detect the wall thinning up to an insulation thickness of 18 mm, whereas the double probe can detect up to 25 mm. The results show that the double core PEC probe has the potential to detect the wall thinning in an insulated pipeline of the NPPs.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.9
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• pp.1439-1447
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• 2019

Objective: The aim of this study was to evaluate the effect of dietary incorporation of tanninrich woody species on meat oxidative stability, carcass traits and meat quality in goats. Methods: Two tannin-rich species were tested using a three-treatments feeding trial, where treatments consisted of: Larrea divaricata and Acacia aroma both at 12.5% in dry matter basis of the diet and a control diet (alfalfa hay). All feeding diets were iso-protein and iso-energy. Carcass conformation, carcass compactness, carcass fatness and subcutaneous fat deposition were evaluated. Intake, liveweigh, Longissimus thoracis et lumborum muscles of goats were analyzed in order to evaluate quality parameters such as pH value, instrumental color evaluation, water holding capacity, total phenolic content, antioxidant activity, meat oxidative stability and fatty acid profiles in meat. Results: Feed intake, liveweight gain, carcass, and meat traits did not differ among treatments. Changes in meat lipid profile among treatments were observed for oleic and elaidic acid contents. Meat total phenolic content and antioxidant activity did not differ among treatments; although, meat oxidative status after storage at room temperature, as well as under refrigerated and frozen conditions were different between control and both supplemented groups. Conclusion: The inclusion of Acacia aroma and Larrea divaricata leaves in goat diet enhanced meat oxidative stability. Modulation of the ruminal biohydrogenation of fatty acids produced by condensed tannins of these plant species need to be further investigated.

• Geomechanics and Engineering
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• v.30 no.6
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• pp.503-515
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• 2022

The permeability coefficient is an essential parameter for the study of seepage flow in fractured rock mass. This paper discusses the feasibility and application value of using readily available RQD (rock quality index) data to estimate mine water inflow and grouting quantity. Firstly, the influence of different fracture frequencies on permeability in a unit area was explored by combining numerical simulation and experiment, and the relationship between fracture frequencies and pressure and flow velocity at the monitoring point in fractured rock mass was obtained. Then, the stochastic function generation program was used to establish the flow analysis model in fractured rock mass to explore the relationship between flow velocity, pressure and analyze the universal law between fracture frequency and permeability. The concepts of fracture width and connectivity are introduced to modify the permeability calculation formula and grouting formula. Finally, based on the on-site grouting water control example, the rock mass quality index is used to estimate the mine water inflow and the grouting quantity. The results show that it is feasible to estimate the fracture frequency and then calculate the permeability coefficient by RQD. The relationship between fracture frequency and RQD is in accordance with exponential function, and the relationship between structure surface frequency and permeability is also in accordance with exponential function. The calculation results are in good agreement with the field monitoring results, which verifies the rationality of the calculation method. The relationship between the rock mass RQD index and the rock mass permeability established in this paper can be used to invert the mechanical parameters of the rock mass or to judge the permeability and safety of the rock mass by using the mechanical parameters of the rock mass, which is of great significance to the prediction of mine water inflow and the safety evaluation of water inrush disaster management.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.3
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• pp.198-208
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• 2023

In order to enhance competitiveness in the industry, financial companies are building a high level of customer satisfaction and repurchase intention by further strengthening not only the technical quality of the platform business but also the customer-oriented service quality. Theoretically, it is time for a theoretical review of whether the expansion of service quality using platform business in the financial industry is directly linked to the performance of financial companies, such as satisfaction and repurchase intention of existing customers. Based on the rapid growth of mobile and the main activities of financial platform companies above, This study attempted to test a significant impact on customer satisfaction and reuse intention on information services and system services, which are service quality of mobile financial platforms. Even if a number of financial companies compete with each other, they could survive by dividing the market, In the digital environment, customers have free access, so the winner can monopolize the market. It is an environment in which customers can move to platform companies that provide better services. The contents presented through the results in this study will be able to be used strategically in terms of the implementation and operation of the financial platform. In addition, it served as an opportunity to find independent variables that affect customer satisfaction and reuse intention, which are financial platform service quality, and suggested the possibility of continuous development of the platform in the future. In summary, the service quality of financial platforms can further expand users by emphasizing user visibility in terms of information services and utilizing user-centered financial platforms that increase customer satisfaction and reliability by strengthening the responsiveness and ease of system services. This study is of important value and is believed to have laid an important foundation for future research.

• The Journal of the Korea Contents Association
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• v.15 no.1
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• pp.123-131
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• 2015

The purpose of this study was to find out the reason why the integration policy of local government in 2010~2014 has failed in the light of multi-dimensional model including normative, structural, constituentive, and technical dimension. Central government pushed integration policy of local government focused on increasing economic efficiency based on the theory of economy of scale on 16 regions and 36 local governments. Only one region(Cheong-Ju and Cheong-Won), however, completed integration procedure in 2014. Although most regions don't have common value on integration, and cultural, political ties in normative and structural dimension, central government pushed the integration policy. Futhermore central government failed to coordinate various interests of the participants and design incentive system including demands of local residents in constituentive and technical dimension. Based on this study central government should consider these policy implications when it propel the integration policy of local government in the future.