• International Journal of Aeronautical and Space Sciences
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• v.8 no.1
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• pp.32-45
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• 2007

The T-50 advanced supersonic jet trainer employs the Relaxed Static Stability (RSS) concept to improve the aerodynamic performance while the flight control system stabilizes the unstable aircraft and provides adequate handling qualities. The T-50 flight control laws employ a proportional-plus-integral type controller based on a dynamic inversion method in longitudinal axis and a proportional type controller based on a blended roll system with simple roll rate feedback and beta-betadot feedback system. These control laws are verified by flight tests with various maneuver set flight envelopes and the control laws are updated to resolve flight test issues. This paper describes several concepts of flight control laws used in T-50 to resolve those flight test issues. Control laws for solving the roll-off problem during pitch maneuver in asymmetric loading configurations, improving the departure resistance in negative angle of attack conditions and enhancing the fine tracking performance in air-to-air tracking maneuvers are described with flight test data.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.513-516
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• 2013

Earthmoving equipment's haul-route has a great influence on the productivity of the earth work operation. Haul-route grade is a critical factor in selecting the haul-route. The route that has low grade resistance contributes to increase machine travel speed and production. This study presents a mathematical model called "Hauling-Unit Optimal Routes Selecting system" (HUORS). The system identifies optimal path that maximize the earth-work productivity. It consists of 3 modules, i.e., (1) Module 1 which inputs site characteristic data and computes site location and elevation using GIS(Geographical Information System); (2) Module 2 which calculates haul time; (3) Module 3 which displays an optimum haul-route by considering the haul-route's gradient resistances (i.e., from the departure to the destination) and hauling time. This paper presents the system prototype in detail. A case study is presented to demonstrate the system and verifies the validity of the model.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1615-1622
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• 2010

Recently, there has been an increase in interest from the aspects of transshipment and connection between the means of transportation. Not only for passengers but also for freight transportation as the need for transportation efficiency is growing while the importance of logistic railway transportation is emerging. The domestic freight transportation is carried out by roads, railroads, ships, and port. However, as other means of transportation, except road, is impossible for Door to Door Service, multimodal transportation accompanied by road transportation is carried out. Here, even though 'transshipment' occurs, because of the lack of basic data regarding this, it is difficult to reflect it in the demand forecasting. With respect to the Korean freight O-D, it was very difficult to have equivalent comparison on the competitiveness and availability of transportation services between the point of departure and the final destination. Taking into account the study of implementation of logit model considering the time and cost of transshipment of multimodal transportation and the transshipment resistance value upon selecting means of freight transportation on multimodal transportation was comparatively insufficient. This study consisted of questionnaire targeting shippers, and based on this, transshipment resistance value was calculated by deriving utility function. By doing so, I intend to examine the effect 'transshipment' has on selecting the means of transportation occurring from freight transportation.

• Journal of Korean Society of Transportation
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• v.27 no.1
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• pp.35-42
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• 2009

One of the problems we face up at the time of planning or improving a transportation transfer facility is which modes and how close we have to put together. The goal here is to keep the connecting transportation mode as close as possible to the prime transit mode, so people travel a minimum transfer path, a distance from one mode to another. Too much a physical separation between modes will limit, even with an intensive improvement of the component links, the level of service of a transfer path as a whole. This study defined a transfer path as the whole stretch of the distance from an arrival point of one mode to the departure point of the connecting mode. The transfer path was divided into three typical segments as side walk, stairways, and indoor corridors. Preference surveys were made for each of these segments, resulting in relative resistance. The sum of individual segments weighted with the relative resistance will make a transfer resistance of the path, which in turn constitutes a transfer utility function together with the overall satisfaction score obtained by the interview survey. The transfer utility function has been utilized to evaluate the transfer distance between modes.

• Korean Journal of Food Science and Technology
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• v.24 no.2
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• pp.127-131
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• 1992

The effects of chlorine treatment on the rheological properties (farinogram, extensogram, amylogram) of soft white wheat flour were studied by treating flour with different amounts (1, 2 and 4 ounces per 100 pounds of flour) of liquidized chlorine gas. Departure time, water absorption and dough stability increased while mechanical tolerance index decreased as the level of chlorine increased. It was appeared that extensibility and resistance at chlorine level of 1 to 2 oz was appropriate for baking properties of flour compared to those of untreated wheat flour. The temperature at maximum viscosity increased gradually with increasing levels of chlorine. It was noted that maximum viscosity was greatly increased at 4 oz compared to those of lower levels of chlorine treatment.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.3
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• pp.72-86
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• 2018

Schedule-based public transit routing algorithm computes a single route that calculated minimum travel time using the departure and arrival times for each stop according to vehicle operation plan. However, additional factors such as transfer resistance and alternative route choice are not reflected in the path finding process. Therefore, this paper proposes a improved RAPTOR that reflected transfer resistance and multi-path searching. Transfer resistance is applied at the time of transfer and different values can be set according to type of transit mode. In this study, we analyzed the algorithm's before and after results compared with actual route of passengers. It is confirmed that the proposed algorithm reflects the various route selection criteria of passengers.

• Nuclear Engineering and Technology
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• v.37 no.4
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• pp.363-374
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• 2005

A heterogeneous thorium-based Kyung Hee Thorium Fuel (KTF) assembly design was assessed for application in the APR-1400 to study the feasibility of using thorium fuel in a conventional pressurized water reactor (PWR). Thermal hydraulic safety was examined for the thorium-based APR-1400 core, focusing on the Departure from Nucleate Boiling Ratio (DNBR) and Large Break Loss of Coolant Accident (LBLOCA) analysis. To satisfy the minimum DNBR (MDNBR) safety limit condition, MDNBR>1.3, a new grid design was adopted, that enabled grids in the seed and blanket assemblies to have different loss coefficients to the coolant flow. The fuel radius of the blanket was enlarged to increase the mass flow rate in the seed channel. Under transient conditions, the MDNBR values for the Beginning of Cycle (BOC), Middle of Cycle (MOC), and End of Cycle (EOC) were 1.367, 1.465, and 1.554, respectively, despite the high power tilt across the seed and blanket. Anticipated transient for the DNBR analysis were simulated at conditions of $112\%$ over-power, $95\%$ flow rate, and $2^{\circ}C$ higher inlet temperature. The maximum peak cladding temperature (PCT) was 1,173K for the severe accident condition of the LBLOCA, while the limit condition was 1,477K. The proliferation resistance potential of the thorium-based core was found to be much higher than that of the conventional $UO_2$ fuel core, $25\%$ larger in Bare Critical Mass (BCM), $60\%$ larger in Spontaneous Neutron Source (SNS), and $155\%$ larger in Thermal Generation (TG) rate; however, the radio-toxicity of the spent fuel was higher than that of $UO_2$ fuel, making it more environmentally unfriendly due to its high burnup rate.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.10
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• pp.60-67
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• 2005

Modern version of supersonic jet fighter aircraft must have guaranteed appropriate controllability and stability in HAoA(high angle of attack). Limit value of aircraft entering into the deep stall in HAoA is related to aircraft configuration design. But, In order to guarantee the aircraft's safety in HAoA, control law for HAoA region implemented in digital Fly-By-Wire flight control system of supersonic jet fighter. The AoA limiter is designed for positive HAoA in longitudinal control law. But, aircraft departure during aggressive negative pitch maneuver such as push over in departure resistance flight test. Therefore negative AoA limiter is needed in longitudinal control law. Result of T-50 flight test show that the AoA is exceed the limit value during aggressive positive pitch maneuver in pull up of power approach mode. In this paper, the AoA limit control law in positive and negative AoA was proposed in order to improve aircraft controllability and stability.

• Journal of the Korean Society of Costume
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• v.64 no.6
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• pp.102-119
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• 2014

The purpose of this study is to develop various designs through renewing and changing perception of accessories by examining various and arbitrary Kitsch. For the method of this study, literature review was mainly used for research of formative characteristics in Kitsch fashion. 798 pieces of work from fashion magazines and website with a focus on Milan, Paris, London and New York collections, in the decade of 2000-2010 were collected. The results of this study are as follows. First, the characteristic of exaggeration is classified into two types: the visual exaggeration, which is characterized by psychological expression through excessive images and (2) the collecting exaggeration, which is not simple but a want of large quantities. Second, the characteristic of satire is classified into two types: (1) the imitation-satire, which satirizes messages to societies with creative humor by using easily consumed materials and (2) the resistance-satire, which is destructive and offensive against isolation and desolation of a capitalistic society. Third, the characteristic of amusement is classified into two types: (1) the playful-amusement, which raises a laugh slyly by using clever materials and (2) the childish-amusement, which involves childish imagination and humor-sense because of desire to be a child. Fourth, the characteristic of nostalgia is classified into two types: (1) the romantic character expressing a departure from modern society, which is desolate because of the urbanization process, and (2) the intermediate character recreating an esthetic category by interacting with different and relative elements. Fifth, the characteristic of inappropriateness is expressed through a deliberate mistake, and it denies existing senses of beauty by overturning common sense and creating new senses of beauty, expressions in distortion and modification of stereotype.

• Nuclear Engineering and Technology
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• v.28 no.2
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• pp.162-174
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• 1996

The local hydraulic characteristics in a single phase flow of a 6$\times$6 rod bundle with neighboring different spacer grids were measured by using a LDV(Laser Doppler Velocimeter) system. 6$\times$6 rod bundle is formed by two 3$\times$6 rod bundles with different spacer grids. The objective of this study in a rod bundle is to investigate the thermal-hydraulic interactions between different spacer grids with different configurations and resistance. By using a LDV system, the velocity and turbulent intensity in axial and horizontal directions ore measured. Pressure drop measurements ore also performed to evaluate the loss coefficient for the spacer grid and the friction factor for rod bundles. Implications concerning thermal mining due to spacer grids were investigated based on the hydraulic test results. Swirl factor, which is assumed as a qualitative criteria for DNB(departure from nucleate boiling), was defined and estimated from the horizontal velocity result.