PURPOSES: The urban traffic problems can be defined as general problems for smooth traffic flow including maintenance of mass transportation system according to suddenly increased population, traffic regulations for vehicles and pollution problem. As a method for solving traffic jams, one of the traffic problems of late, interest in Intelligent Traffic System(ITS) is increasing sharply, which is a system managing traffic demand by providing passers with information on traffic state of path and road conditions before they pass the road through ATIS, a field of ITS. METHODS: Variable message signs(VMS) is used on the roads as a method for providing information to promote smooth traffic flow and safety and prevent traffic accidents in advance by providing drivers with various information while driving. RESULTS: Recently, as ITS industry has been vitalized and technical factors of VMS have developed, various kinds of information is provided but the effect of VMS has not been maximized due to its limited type. CONCLUSIONS: Therefore, this study intends to provide methods for effective information transfer by analyzing driver's visual behavior characteristics for VMS and presenting a basis for maximizing VMS effect after considering read by expression type.

The Cu2ZnSnS4 (CZTS) thin film solar cell is a candidate next generation thin film solar cell. For the application of an absorption layer in solar cells, CZTS thin films were deposited by pulsed laser deposition (PLD) at substrate temperature of 300˚C without post annealing process. Deposition time was carefully adjusted as the main experimental variable. Regardless of deposition time, single phase CZTS thin films are obtained with no existence of secondary phases. Irregularly-shaped grains are densely formed on the surface of CZTS thin films. With increasing deposition time, the grain size increases and the thickness of the CZTS thin films increases from 0.16 to 1μm. The variation of the surface morphology and thickness of the CZTS thin films depends on the deposition time. The stoichiometry of all CZTS thin films shows a Cu-rich and S-poor state. Sn content gradually increases as deposition time increases. Secondary ion mass spectrometry was carried out to evaluate the elemental depth distribution in CZTS thin films. The optimal deposition time to grow CZTS thin films is 150 min. In this study, we show the effect of deposition time on the structural properties of CZTS thin film deposited on soda lime glass (SLG) substrate using PLD. We present a comprehensive evaluation of CZTS thin films.

무등산도립공원 주요 거점의 시간대별 탐방객 이동패턴을 파악하여 관리방안을 제안하기 위해 증심사지구, 원효사지구, 중머리재 등 주요 지점에서 계절별로 3일씩, 오전 7시부터 오후 7시까지 출입하는 탐방객 수를 조사하였다. 조사결과 무등산도립공원 주요 출입구인 증심사지구와 원효사지구에서는 대부분 오전 9시부터 오후 2시 사이에 입장하였고, 오전 10시에서 11시 사이에 입장객 수가 가장 많았다. 퇴장시간은 대부분 오전 12시부터 오후 5시 사이였으며, 피크시간은 오후 2시부터 4시 사이었다. 중머리재를 방문하는 탐방객들은 대부분 오전 11시에서 오후 3시 사이에 중머리재를 경유하여 장불재나 중봉방향으로 등산하거나 증심사지구나 원효사지구로 하산하였는데 오전 11시부터 오후 1시까지가 피크시간 이였다. 한편, 요일과 계절에 따른 시간대별 이동 패턴에는 뚜렷한 경향이 나타나지 않았다. 공원자원 보전과 탐방만족도 증진을 위해서 탐방객이 집중되는 장소와 시간을 중심으로 탐방안내, 캠페인, 훼손지복원 등 집중관리가 필요하다.

일반적으로 중성용액 하에서 알루미늄 합금은 부동태피막(Al2O3나 Al2O3·3H2O)을 형성한다. 그러나, 해수 환경에서 염소이온이 표면에 생성된 부동태 피막을 파괴하여 부식이 발생하게 된다. 본 연구에서는 해수환경 하에서 부식 문제점을 해결하기 위해 Al-4.5%Mg-0.6%Mn 알루미늄 합금에 대하여 정전위 방식 기술을 적용하였다. 분극실험결과, 개로전위보다 귀한 전위에서는 활성 용해 반응이 나타났으며 개로전위 보다 비한 전위에서는 용존산소 환원에 의한 농도 분극과 활성화 분극이 관찰되었다. 정전위 실험결과, 농도 분극에서 활성화 분극으로 전환되는 전위부터 적용 시간이 증가할수록 전착물이 많이 생성되었으며, 부분적으로 전착물과 모재의 계면사이에서 틈부식이 관찰되었다. 전체적으로 정전위 양극분극실험시, 활성용해반응이 발생하여 정전위 방식 기술을 적용하기 어려운 반면, 정전위 음극분극 실험시 방식 전위인 농도분극 범위내에서 적용 시간을 고려하여 최적 방식 조건을 -1.1 V~-0.75 V로 규명하였다.

본 연구는 수출용 딸기 '매향' 품종을 09:00와 14:00에 각각 수확하여 4℃ 예냉 처리 혹은 예냉 무처리 후 4℃와 8℃에 저장하면서 딸기의 품질변화와 상품성 유지 효과를 구명하기 위해 수행되었다. 2010년 5월 4일에 숙도 60%의 과실을 경상남도 진주지역 상업적 온실에서 수확하였다. 농가의 예냉기에서 3시간 동안 예냉한 딸기를 30분 만에 실험실로 수송하고, 즉시 저장고에 저장하였다. 예냉은 농가 현장에 설치되어 있는 간이 예냉기를 이용하였다. 과실은 PVC랩과 골판지상자에 포장 된 후 4℃와 8℃의 항온 저장고에 두어 실험하였다. 저장하는 동안 딸기의 무게변화, 경도, 색도, 당도, 잿빛곰팡이 발생률을 이틀 간격으로 2010년 5월 6일부터 5월 14일까지 조사하였다. 숙도가 진행됨에 따라 경도 및 당도가 감소하였다. Hunter 'L'과 'a' 값은 시간이 경과함에 따라 감소하였다. 또한 모든 온도처리에서 저장 기간이 경과함에 따라 무게의 변화가 감소하였다. 과실의 표피조직에 무름병의 발생 시작 후 잿빛곰팡이가 발생하였다. 잿빛곰팡이는 저장온도 4℃ 처리구에서 보다는 8℃ 처리구에서 가장 많이 발생하였다. 하지만 수확 시간과 예냉 유무에 따른 저장성의 차이는 나타나지 않았다. 본 연구는 4℃ 예냉처리 후 4℃에서 저장하였을 때 신선도가 가장 오래 유지되었다.

Information on time spent in microenvironments has a critical role in individuals’ exposure assessment. Time-activity studies have become an integral part of comprehensive exposure assessment and personal exposure modeling. The aims of this study were to estimate the exposure level of NO₂, PM₁₀ and VOCs, and to compare the estimated exposure by using time-activity pattern and indoor air concentration. This study was performed upon 28 university students living in Daegu. We measured air pollutants of NO₂, PM₁₀ and VOCs at houses where the university students spent most their times. In this study, according to the summer and winter, time-activity patterns of university students were different. The 28 university students average spending times in house indoors and other indoors time were 11.52±2.14 and 7.63±2.65 hours in summer, and 14.78±3.30 and 6.59±3.03 hours in winter, respectively. The university students personal exposure NO₂ concentrations were average 21.62±5.88 ppb and I/O ratio was 0.89±0.27. Personal average exposure of PM₁₀ concentration was between house indoors and outdoors concentrations which indoor house concentration was 37.68±7.57 μg/m³ and outdoor house concentration was 43.85±9.80 μg/m³ with 0.88±0.17 of I/O ratio. Personal exposure to benzene and the average concentration of benzene did not exceed in atmosphere environmental standard (annual 1.5 ppb) and the outdoor houses concentration was much higher than indoor houses.

A possible heuristic to solve metropolitan area vehicle routing problems with variable vehicle speeds is suggested in this research. Delivery hours are classified into 4 different time zones to make variable vehicle speeds no change within the same time zone to make TDVRP simple to solve. The suggested heuristic consists of 2 stages such as initial solution development step and initial solution improvement step. A computer program using C++ is constructed to evaluate the suggested heuristic. Randomly generated vehicle routing problems are used for the experiments. This heuristic could be helpful to logistics companies by increasing delivery efficiencies since the 4 zone classification is taken from the observed traffic information offered by a local government.

본 연구는 숲에서의 체류시간에 따른 생리적 반응을 분석하여 건강증진에 미치는 효과를 규명하기 위하여 진행되었다. 연구는 전주시 건지산 일원의 편백나무 숲에서 평균 연령 53.33세의 여성 18명을 대상으로 숲 체류 5시간 동안의반응을 측정하였다. 생리적 반응으로 뇌파, 심박변이, 혈압, 맥박 등을 측정한 결과는 다음과 같다.숲에서 체류하는 동안 알파파 발생 빈도가 증가하여 생리적 안정이 이루어졌으며 숲에서 4시간 체류할 때 중추신경계의안정을 통해 스트레스 완화효과의 빈도가 높게 나타났다. 자율신경계 측면에서 이완 및 스트레스 완화를 설명하는부교감신경이 활성화되고 혈압 및 맥박의 감소 효과가 나타난 피험자 집단이 숲 체류 후 증가하였으며 최소 2시간부터4시간까지 효과가 나타난 피험자의 빈도가 지속적으로 높게 나타났다. 전반적으로 생리적 반응분석에 의하면, 숲 체류에따른 스트레스 완화효과에 있어서 숲에서 2-4시간 머무를 때 가장 많은 이용자가 스트레스 완화효과를 얻을 수 있을것으로 판단된다.

목적 : 본 연구에서는 혈관성 치매환자와 알츠하이머 치매환자에게 시간차 회상훈련과 오류배제학습에 대한 훈련을 적용했을 때 인지기능과 우울에 어떠한 변화를 나타내는지 비교해 보고자 한다. 연구방법 : 대전·충남에 2개의 요양병원에서 재활치료를 받고 있는 알츠하이머 치매, 발병 후 6개월이 경과한혈관성 치매환자 31명을 대상으로 1주일에 5회기씩 총 4주간 실시하였다. 치료 중재 전·후 인지기능을 비교하기위해 신경심리평가(The Korean Version of Consortium to Establish a Registry of Alzheimer's Disease; CERAD-K)를 시행하였고, 우울에 미치는 영향을 알아보기 위해 한국판 노인우울척도 검사(Geriatric Depression Scale-K; GDS-K)를 실시하여 분석하였다. 결과 : 두 집단 모두 중재 후 구성회상과 길 만들기 항목을 제외한 모든 항목에서 인지기능이 유의하게 증가되었고, 특히 경도치매, 혈관성 치매환자에게서 유의한 차이를 보였다(p<.05). 우울은 중재 후 경도치매와 혈관성 치매에게서 유의하게 감소하였다(p<.05).결론 : 혈관성치매환자와 경도치매환자에게 인지기능의 증진이 우울에 영향을 미칠 수 있으므로 치매환자에게 인지치료에 대한 고려가 필요하다.

In this study, 5-story structures were designed in accordance with KBC2009 for inelastic time history analysis of RC IMRF. Bending moment-curvature relationship for beam and column was identified with fiber model and bending moment-rotation relationship for beam-column joint was calculated with simple and unified joint shear behavior model and moment equilibrium relationship for the joint. The hysteretic behavior was simulated with three-parameter model suggested in IDARC program. The analytical results showed that the inelastic shear behavior of the joint could be neglected in the structural design for seismic design category C but the structure of category D did not satisfy the criteria of FEMA 356 for collapse prevention performance level.

PURPOSES : The accuracy of travel time information is a key measure of effectiveness and reliability of advanced traveler information systems. This study aims at investigating drivers' perception on the acceptable level of information accuracy and their corresponding valuations. METHODS : A questionnaire survey was executed for collecting driver perception data to capture the expectation level of travel time information provided and their willingness to pay for the information. A Tobit model was adopted for exploring the relationship among the acceptable level, driver socioeconomic characteristics and travel attributes. Since drivers' willingness to pay for accurate travel time information can be different according to their travel lengths, a piecewise linear regression model was developed to capture the sensitivity of values of travel time information to travel length. RESULTS : The analysis results suggest that trip purpose and travel time are two dominant factors to determine drivers' acceptable level of travel time information. For business and short trips, drivers want more accurate information than for non-business and long trips. Drivers' willingness to pay for travel time information also varies depending on their incomes, trip purposes and travel lengths. The results also show that drivers' valuation of travel time information provided is sensitive to their travel length. For longer trips, drivers are less sensitive to travel time information and then put less value on the information provided. CONCLUSIONS : Censored nonlinear regression models are developed to estimate drivers' acceptable accuracy for travel time information and their valuation using questionnaire survey data. The findings on drivers perception to the required accuracy of travel time information and their corresponding willingness to pay can be used in the design and deployment of advanced traveler information system to improve its effectiveness and usefulness through high compliance.

An acoustic method for discriminating plankton from fish, in Lake Dom Helvecio of Brazil, is developed. The flow of data from this method is comprised of time varied threshold (TVT), dilation filter, bitmap and mask functions. The TVT can, of itself, precisely explain how to select an appropriate value. The final results of the echogram, which only shows plankton by masking fish signals, is used to examine the acoustic density of plankton by depth and time. The results indicate that the acoustic density of the plankton is at a depth of between 5m to 15m, its density is especially high at 10m to 15m. The results of the acoustic density of plankton by time indicate that May 7 is higher in density than May 8. Future study plans include the use of net samples, environmental datasets to identify the abundance and ecology described by the Chaoborus spp. from other species.

Enhancement of light trapping in solar cells is becoming increasingly urgent for the development of next generation thin film solar cells. One of the possible candidates for increasing light trapping in thin film solar cells that has emerged recently is the use of scattering from metallic nanostructures. In this study, we have investigated the effects of the geometric parameters of Ag nanorings on the light scattering efficiency by using three dimensional Finite Different Time Domain (FDTD) calculations. We have found that the forward scattering of incident radiation from Ag nanorings strongly depends on the geometric parameters of the nanostructures such as diameter, height, etc. The forward scattering to substrate direction is increased as the outer diameter and height of the nanorings decrease. In particular, for nanorings larger than 200 nm, the inner diameter of Ag nanorings should be optimized to enhance the forward scattering efficiency. Light absorption and scattering efficiency calculations for the various nanoring arrays revealed that the periodicity of nanorings arrays also plays an important role in the absorption and the scattering efficiency enhancement. Light scattering efficiency calculations for nanoring arrays also revealed that enhancement of scattering efficiency could be utilized to enhance the light absorption through the forward scattering mechanism.

PURPOSES: Suggestion of asphalt binder constitutive model based on time-temperature superposition principle and overstress concept in order to describe behavior of asphalt binders. METHODS: A series of temperature sweep tests and multiple stress creep and recovery(MSCR) tests are performed to verify the applicability of time-temperature superposition principle(t-Ts) and to develop viscoelastoplastic constitutive equation based on overstress concept. For the tests, temperature sweep tests at various high temperature and various frequency and MSCR test at 58℃, 64℃ 70℃, 76℃, and 82℃ are performed. From the temperature sweep tests, dynamic shear modulus mastercurve and time-temperature shift function are built and the shift function and MSCR at 58℃ are utilized to determine model coefficients of VBO model. RESULTS: It is observed that the time-temperature shift function built at low strain level of 0.1% is applicable not only to 1.0% strain level temperature sweep test but also maximum 500,00% strain level of MSCR test. As well, the modified VBO model shows perfect prediction on MSCR measured strain at the other temperatures. CONCLUSIONS: The Time-temperature superposition principle stands hold from very low strain level to very high strain level and that the modified VBO model can be applicable for various range of strain and temperature region to predict elastic, viscoelastic, and viscoplastic strain of asphalt binders.