• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.6
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• pp.63-71
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• 2018

Strands with ultimate strength of 2,400 MPa was developed and applied in the KCI Code and the KS standard. A high-strength prestressed strand to be applied to a structure, a suitable anchorage system should be used together. Recently, a post tension anchorage for 2,400 MPa strands was developed. but there is not much research on performance evaluation. Therefore, in this study, structural analysis of local zone with 9 strands, 15 strands, and 19 strands anchorage were investigated respectively, which are most widely used for post tensioning anchorages with 2,400 MPa strands, according to PTI anchorage zone design method, and Load transfer performance from ETAG013 and/or KCI-PS101 was evaluated. Furthermore, the adequacy of the test was also analyzed by nonlinear numerical analysis. As results, the anchorages with 2,400 MPa strands satisfied the structural performance of the local area and satisfied the load transfer performance condition.

• Geomechanics and Engineering
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• v.34 no.6
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• pp.683-696
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• 2023

The destruction and fracture of rock masses are crucial components in engineering and there is an increasing demand for the study of the influence of rock mass heterogeneity on the safety of engineering projects. The numerical manifold method (NMM) has a unified solution format for continuous and discontinuous problems. In most NMM studies, material homogeneity has been assumed and despite this simplification, fracture mechanics remain complex and simulations are inefficient because of the complicated topology updating operations that are needed after crack propagation. These operations become computationally expensive especially in the cases of heterogeneous materials. In this study, a heterogeneous model algorithm based on stochastic theory was developed and introduced into the NMM. A new fracture algorithm was developed to simulate the rupture zone. The algorithm was validated for the examples of the four-point shear beam and semi-circular bend. Results show that the algorithm can efficiently simulate the rupture zone of heterogeneous rock masses. Heterogeneity has a powerful effect on the macroscopic failure characteristics and uniaxial compressive strength of rock masses. The peak strength of homogeneous material (with heterogeneity or standard deviation of 0) is 2.4 times that of heterogeneous material (with heterogeneity of 11.0). Moreover, the local distribution of parameter values can affect the configuration of rupture zones in rock masses. The local distribution also influences the peak value on the stress-strain curve and the residual strength. The post-peak stress-strain curve envelope from 60 random calculations can be used as an estimate of the strength of engineering rock masses.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.1
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• pp.29-41
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• 1996

The two-stage numerical model was used to study the relation between three-dimensional local wind model, advection/diffusion model of random walk method and second moment method on Pusan coastal area. The first stage is three dimensional time-dependent local wind model which gives the wind field and vertical dirrusion coefficient. The second stage is advection/diffusion model which uses the results of the first stage as input data. First, wind fields on Pusan coastal area for none synoptic scale wind showed typical land and sea breeze circulation, and convergence zone occured at 1200LST in northern of domain, in succession, moved northward of domain. Emissions from Sinpyeong industrial district were trasnported toward the inland by sea breeze during daytime, and reached the end part of domain about 1800LST. During nighttime, emissions return to sea by land breeze and vertical diffusion also contributes to upward transport. In order to use this model for forecast of air pollution concentration on the Pusan coastal area, it is necessary that computed value must be compared with measured value and wind fields model must also be dealt in detail.

• Journal of Agricultural Extension & Community Development
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• v.13 no.2
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• pp.341-355
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• 2006

The purpose of this study is to introduce the case of advancement of rural zoning system in a local government of Japan. The Matzgawa county, one of the local governments in Japan, sets up a new zoning system which advanced in using rural resources. In order to develop and revitalize rural region, it is necessary to use all kinds of rural resources, including agricultural as well as non-agricultural resources comprehensively. Also, the classification of agricultural land use should be reformed. The zoning on rural land should be changed to include not only agricultural use but also non-agricultural use, so as to manage comprehensively agricultural land use and its conversions. Furthermore, the land use regulation should be applied to each zone of the agricultural land.

• Journal of Drive and Control
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• v.17 no.4
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• pp.8-14
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• 2020

Intelligent devices using ICT technology have been introduced in the field of construction machinery to improve productivity and stability. Among the intelligent devices, Machine Guidance is a device that provides real-time posture, location, and work range to drivers by installing various sensors, controllers, and satellite navigation systems on construction machines. Conversely, the efficiency of equipment that requires location information, such as machine guidance, will be greatly reduced in buildings, and tunnels in the GPS blind spots. Thus, the other high-precision positioning technologies are required in the GPS blind spot zone. In this study, we will develop a relative position measurement system that provides precise location information such as construction machinery and robots in a local area where the GPS reception is difficult. A relative position measurement system tracks a marker in the form of a sphere installed on a vehicle by using the image base tracking technology, and measures the distance and direction information to the marker to calculate a position.

• Korean Journal of Radiology
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• v.25 no.1
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• pp.33-42
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• 2024

Focal enhancement typically suggests local tumor progression (LTP) after renal cell carcinoma is percutaneously ablated. However, evaluating findings that are false positive or negative of LTP is less familiar to radiologists who have little experience with renal ablation. Various imaging features are encountered during and after thermal ablation. Ablation procedures and previous follow-up imaging should be reviewed before determining if there is LTP. Previous studies have focused on detecting the presence or absence of focal enhancement within the ablation zone. Therefore, various diagnostic pitfalls can be experienced using computed tomography or magnetic resonance imaging examinations. This review aimed to assess how to read images during or after ablation procedures, recognize imaging features of LTP and determine factors that influence LTP.

• Journal of Korea Port Economic Association
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• v.19 no.1
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• pp.161-188
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• 2003

The purpose of this paper is to investigate CFZ(custom free zone) and FTZ(free trade zone) in Korean FTZ System and develop Masan Port in Korea Local Port. The main point of this discussion is to approach the efficient method ill developing Masan Port through comparison CFZ and FTZ. For this purpose, this paper is searched the present situation of logistics in Korea and Northeast Asia, also discussed the concept of FTZ in international status. Then CFZ accepted by Korean government started from the concept of FTZ and is the logistic-centered FTZ in the middle of three model, production-centerde model, production-logistic combination, and logistic-centered FTZ. But CFZ in centering logistic excepted the fundamental manufacture in Korean production. and is almost the same about other various sides, i. e. law and enforcement ordinance. etc This problem is decreasing the efficiency in Korean commercial system. Thus this paper indicate the view point and rightness of region economic through study of FTZ and CFZ in Masan Port. This paper says that FTZ is better then CFZ in Masan Port with comparing superior position about economic development direction, industrial structure, Foreign investment attraction, business fluctuation, national-local renovation. Therefore this paper concludes that the development of Masan Port needs the effort as follow : first, Masan Port must apply in enlarging FTA into Free Tree Area. Second, the government must develop the high-density and medium-small scale in Masan Port. Third, the local government must promote the amount of demand in Masan Port logistic. Forth, the government must actively propel great-sphere development in present Masan Port.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.5
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• pp.38-48
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• 2010

Adverse weather (e.g. strong winds, snow and ice) will probably appear as a more serious and frequent threat to road traffic than in clear climate. Another consequence of climate change with a natural disastrous on road traffic is respond to traffic accident more the large and high-rise bridge zone, tunnel zone, inclined plane zone and de-icing zone than any other zone, which in turn calls for continuous adaption of monitoring procedures. Accident mitigating measures against this accident category may consist of intense winter maintenance, the use of road weather information systems for data collection and early warnings, road surveillance and traffic control. While hazard from reduced road friction due to snow and ice may be eliminated by snow removal and de-icing measures, the effect of strong winds on road traffic are not easily avoided. The purpose of the study described here, was to design of amber information the relationship between traffic safety, weather, user information on road weather and driving conditions in local-scale Geographic. The most applications are the optimization of the amber information definition, improvements to road surveillance, road weather monitoring and improved accuracy of user information delivery. Also, statistics on wind gust, surface condition, vehicle category and other relevant parameters for wind induced accidents provide basis for traffic control, early warning policies and driver education for improved road safety at bad weather-exposed locations.

• Journal of Korean Society of Rural Planning
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• v.20 no.1
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• pp.147-159
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• 2014

This study aims to draw up a basic plan to construct an agricultural theme park in a farming city as a way of establishing its regional identity represented by "Three Whites". Sangju, Kyongsangbuk-do which is the subject area of the study has been well-known for "Three Whites (rice, silkworm cocoon and dried persimmon)." The purpose of the study is to take a closer look at the folk life and culture of Sangju and develop tourism resources to promote regional development and competitiveness of the city. This study was conducted in several phases in consideration of the characteristics of plan and design, on the basis of the theoretical review of agricultural tourism. In the first phase, planning conditions were analyzed as per development objectives. In the second phase, strategies and concepts were established for the theme park, based on which development methods were decided by phase and facility. Then, a preliminary review was conducted on functions and facilities to introduce to the theme park. In the third phase, a comprehensive plan was drawn up, which includes basic plans for respective parts. In consideration of the characteristics of the study, construction was not looked at in detail. The total size of land subject to the study is approx. $97,960m^2$, which was divided into four separate zones--Sambaek Cultural Experience Zone, Natural Observation & Experience Zone, Agricultural Life Experience Zone and other facilities zone--in order to connect facilities, functions and experience with the physical characteristics of the city, and separate space planning was conducted for each zone. The outcome of the study carries significance as an example of alternative tourism which considers regional characteristics, develops local resources and makes use of obsolete rural facilities, in what is called the eco-friendly development where nature and eco-system, landscape and culture, and recreation and leisure come together as one.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.6
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• pp.1093-1099
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• 2016

Currently, there are 499 metropolitan subway stations in Korea, but there are not many studies on the influence zone of linkage between railway station and public transport. Existing studies have been studied almost in terms of accessibility.. In addition, the existing research on the influence zone of linkage using survey data and statistics, there is a limit to the theoretical basis and analysis techniques. In this paper, we propose a new method to select on the influence zone of linkage, It is a GIS analysis technique using the spatial data of the railway station user as the large data of the traffic card. We applied the GIS analysis technique for select the influence zone of linkage based on the travel time of the network for each public transportation system. As a result, it was confirmed that the influence of the link of 15 minutes on the local bus, 20 minutes on the city bus and 25 minutes on the intercity bus were clearly distinguished according to the difference in network access time.