• 한국ITS학회 논문지
• /
• 제10권2호
• /
• pp.66-76
• /
• 2011

관광지ITS는 해당 관광지역에 관련한 관광과 교통(명승지, 도로망, 주차, 소요시간 등)에 관한 정보를 제공하는 시스템이다. 하지만 관광주유행동의 관점에서 관광지 정보제공 시스템이 아직 충분히 고려되지 못하고 있다. 관광주유행동의 의사결정에 있어 다양한 정보 니즈가 존재하기 때문에 정보이용과 주유행동의 관련성이 매우 중요하다. 본 연구는 관광지ITS구축을 향한 기본적인 정보니즈 분석과 기존 주유행동 모형 재구축의 기초적 시사점 도출을 목적으로 후지5호 관광지의 정보이용과 주유행동의 관련성 분석을 수행하였다. 구조방정식을 이용한 관련성 분석결과, 주유행동의 단계에 따른 정보이용이 지역인지도와 주유행동에 영향을 미치고 있었다. 이는 관광주유행동분야에서도 정보에 의존하고 있다는 점을 밝히고 있다. 또한 이러한 결과는 관광지ITS에 관한 기초적 정보를 제시하고 있다.

• 대한토목학회논문집
• /
• 제30권4D호
• /
• pp.339-349
• /
• 2010

본 논문은 관광객의 정보이용을 고려한 관광주유행동 분석 목적으로 구조방정식 시스템을 적용한 모형을 구축하였다. 관광주유행동은 관광지 도착이후부터 귀가까지를 다루는 것으로 관광지내 활동과 시간, 관광지점수 등의 지표로 설명하고 있다. 이러한 관광주유행동지표들은 상호 상관관계가 있다는 가정에 구조방정식의 내생변수로 취급하였다. 또한 내생변수들은 지역인지도, 정보이용행동, 개인속성 등에 영향을 받는 것으로 가정하고 있다. 본 모형의 사례분석은 일본 후지 5호 관광지의 관광실태자료를 이용해 수행하였다. 본 연구에서 제안한 관광주유행동 모형은 내생변수간의 공분산관계를 통계적 분석으로 다루는 것이 가능해 기존 이산선택 방법론보다 간단하게 관광지의 정보이용 효과를 분석할 수 있는 장점이 있다.

• 대한토목학회논문집
• /
• 제26권6D호
• /
• pp.909-916
• /
• 2006

본 연구는 후지5호 관광객의 주유행동과 정보이용패턴에 관한 조사에 해당된다. 또한 관광객의 주유행동과 정보이용과의 관계에 초점을 두고 있고, 이러한 관계분석은 군집분석과 수량화 모형을 이용하여 분석하였다. 이 결과 (1) 90%이상의 관광객이 후지5호 관광을 위해 1회 이상 정보를 이용하고 있으며, 여행전, 여행중, 여행전후의 정보이용이 각각 80%, 70%, 60%로 나타났다. (2) 후지5호지역의 정보이용 패턴은 3개 패턴으로 구분되었고, (3) 시 공간적 주유행동 지표(주유행동개시 및 종료시각, 체재시간, 관광지점수 등)는 각 정보이용패턴에 따른 차이가 확인 되었고, (4) 수량화 모형에서는 관광객의 주유행동지표(관광지점수, 체재시간)에 대한 의사결정이 정보이용에 의존하고 있다는 것이 확인되었다.

• 대한용접접합학회:학술대회논문집
• /
• 대한용접접합학회 1998년도 특별강연 및 춘계학술발표 개요집
• /
• pp.144-146
• /
• 1998

• ETRI Journal
• /
• 제25권6호
• /
• pp.531-534
• /
• 2003

This report describes the effect of optical delay on the suppression of the power transient excursion in a combined gain-controlled erbium-doped fiber amplifier with an internal optical feedback loop (OFL). A simple homogeneous model showed that the optical delay caused a phase change in the oscillation of the surviving and laser channels, which resulted in a reduction of the overall power transient excursion. In addition to the reduction, a real system with a 1528.7-nm OFL shifted the oscillation upward or downward according to channel removal or addition, whereas another one with a 1560.9-nm OFL did not. This different transient behavior reflected a control-wavelength dependence on optical automatic gain control, where spectral-hole burning dominated over relaxation oscillation for 1528.7 nm, and vice versa for 1560.9 nm.

• 한국자동차공학회논문집
• /
• 제4권6호
• /
• pp.144-152
• /
• 1996

In the sequential MPI system with one injection for each cycle, engine performance is influenced by the mixture conditions. It can be said that engine performance is improved by being better identical mixture formation conditions for all cylinders. As the fuel injection timing to the intake port effects on the mixture formation conditions and the engine performance, injection timing must be better adjusted to engine requirements. Engine behavior was clearly different depending on the injection time during intake storke. Therefore it was studied that injection timing of fuel effects on the engine performance I. e. combustion stability, COV(imep), A/F excursion, CO,HC emission concentration and fuel consumption. It was found that late intake-synchronous injection was deteriorated the combustion characteristics and performance characteristics, while early intake-synchronous infection resulted in favorable engine behavior.

• 대한가정학회지
• /
• 제36권4호
• /
• pp.1-18
• /
• 1998

The purpose of this study was to investigate relationship between the eating behavior, physical and mental health. For this purpose, the data was collected by using questionnaires and intervews distibuted to 293 the elderly residing in Seoul. This study was designed to observe the eating behavior(eating habit, healthy food preference, smoking, drinking), physical health(weight, height, desease and heath of the current and past, self-awareness of the health) and mental health(weight, height, desease and heath of the current and the past, self-awareness of the health) and mental health(meeting, excursion, exercise, service, activi ty, depression). The major results are: 1. The heathy elderly had the better eating habit and the non healthy tried to stop smoking and drinking for their own health. 2. There were many elderly with neuralgia and arthralgia, especially women were worse. The sleep disorder related to many disease. When physical health was bad, so was mental health. 3. More than 50 percentage of subjects had light depression, especially women and the elderly at 60-75age were more serious. The depressive elderly had no meetings, excursion, exercise, service activity and showed a hight tendency for under-weight or obesity. In conclusion, the relationship between the eating behavior and physical and mental health wa very significant, so it was necessary to provide comfortable living condition to the elderly.

• 한국해양공학회지
• /
• 제32권6호
• /
• pp.427-432
• /
• 2018

Tidal current power is one of the energy sources of the ocean. Electricity can be generated by converting the flow energy of the current into the rotational energy of a turbine. Unlike tidal barrage, tidal current power does not require dams, which have a severe environmental impact. A floating-type tidal current power device can reduce the expensive support and installation cost, which usually account for approximately 41% of the total cost. It can also be deployed in relatively deep water using tensioned wires. The dynamic behavior of a floater and turbine force are coupled because the thrust and moment of the turbine affect the floater excursion, and the motion of the floater can affect the incoming speed of the flow into the turbine. To maximize the power generation and stabilize the system, the coupled motion of the floater and turbine must be extensively analyzed. However, unlike pile-fixed devices, there have been few studies involving the motion analysis of a moored-type tidal current power device. In this study, the commercial program OrcaFlex 10.1a was used for a time domain motion analysis. In addition, in-house code was used for an iterative calculation to solve the coupled problems. As a result, it was found that the maximum mooring load of 200 kN and the floater excursion of 5.5 m were increased by the turbine effect. The load that occurred on the mooring system satisfied the safety factor of 1.67 suggested by API. The optimum mooring system for the floating tidal current power device was suggested to maximize the power generation and stability of the floater.

• 한국해안·해양공학회논문집
• /
• 제23권3호
• /
• pp.193-204
• /
• 2011

역동적인 파랑에 노출되는 경우 다양한 failure mode를 쉽게 드러내는 Oil boom의 성능을 개선하기 위해 가장 정교한 파랑모형인 spatially filtered Navier-Stokes 식을 LES (Large Eddy Simulation), 잔차응력에 대한 LDS (Lagrangian Dynamic Smagorinsky 모형), SPH (Smoothed Particle Hydrodynamics) 기법을 활용하여 해석하는 새로운 수치모형이 제언되었다. 이어 부유식 Oil Boom의 누유특성을 규명하기 위해 oil spill, progressive wave, oil boom의 상호작용을 oil boom이 계류삭에 고정되어있는 경우와 oil boom의 excursion이 허용된 경우에 대해 각각 수치모의 하였다. 모의결과 oil boom의 skirt 길이가 수심의 30% 이상이고 excursion이 허용된 경우 oil spill의 차폐 기능은 극대화되는 것으로 밝혀졌다. 이와 더불어 y = 1~2 m 사이에 오일막과 해수의 경계층에서 생성된 와류가 저면으로 확산되면서 시계방향과 반 시계방향의 와류가 엇갈리게 생성되는 coherent eddies가 관측되어 수리실험을 통해 그 존재가 알려진 Kelvin-Helmholz파의 성장과정과 계면으로부터의 일탈과정이 수치모의된 것으로 판단된다.

• Nuclear Engineering and Technology
• /
• 제34권2호
• /
• pp.117-131
• /
• 2002

Core disruptive accidents have been investigated at Korea Atomic Energy Research Institute(KAERI) as part of the work to demonstrate the inherent and ultimate safety of conceptual design of the Korea Advanced Liquid Metal Reactor(KALIMER), a 150 MWe pool- type sodium cooled prototype fast reactor that uses U-Pu-Zr metallic fuel. In this study, a simple method and associated computer program, SCHAMBETA, was developed using a modified Bethe-Tait method to simulate the kinetics and thermodynamic behavior of a homogeneous spherical core over the period of the super-prompt critical power excursion induced by the ramp reactivity insertion. Calculations of the energy release during excursions in the sodium-voided core of the KALIMER were subsequently performed using the SCHAMBETA code for various reactivity insertion rates up to 100 S/s, which has been widely considered to be the upper limit of ramp rates due to fuel compaction. Benchmark calculations were made to compare with the results of more detailed analysis for core meltdown energetics of the oxide fuelled fast reactor. A set of parametric studies were also performed to investigate the sensitivity of the results on the various thermodynamics and reactor parameters.