• Land and Housing Review
• /
• v.11 no.2
• /
• pp.95-104
• /
• 2020

This study aims to explore a purely mechanistic pavement analysis approach where viscoelasticity and fracture of asphalt mixtures are considered to accurately predict deformation and damage behavior of flexible pavements. To do so, the viscoelastic and fracture properties of designated pavement materials are obtained through experiments and a fully mechanistic damage analysis is carried out using a finite element method (FEM). While modeling crack development can be done in various ways, this study uses the cohesive zone approach, which is a well-known fracture mechanics approach to efficiently model crack initiation and propagation. Different pavement configurations and traffic loads are considered based on three main functional classes of roads suggested by FHWA i.e., arterial, collector and local. For each road type, three different material combinations for asphalt concrete (AC) and base layers are considered to study damage behavior of pavement. A concept of the approach is presented and a case study where three different material combinations for AC and base layers are considered is exemplified to investigate progressive damage behavior of pavements when mixture properties and layer configurations were altered. Overall, it can be concluded that mechanistic pavement modeling attempted in this study could differentiate the performance of pavement sections due to varying design inputs. The promising results, although limited yet to be considered a fully practical method, infer that a few mixture tests can be integrated with the finite element modeling of the mixture tests and subsequent structural modeling of pavements to better design mixtures and pavements in a purely mechanistic manner.

• Journal of Korea Spatial Information System Society
• /
• v.10 no.1
• /
• pp.51-63
• /
• 2008

Previous studies for routing In USN (Ubiquitous Sensor Networks) appear to be unreliable due to the dependence on non-spatial data and the lack of map overlay analysis. Multiple spatial parameters and radio propagation modeling techniques were integrated to derive RSSI (Received Signal Strength Indicator) value between route nodes and produce a highly reliable path map. It was possible to identify area-wide patterns of USN route subject to many different Influences (e.g. the specific effects of radio blocking factors such as the visible area, road area, cell duplicated area, and building density), which cannot be acquired by traditional non-spatial modeling. The quantitative evidence concerning the USN route for individual cell as well as entire study area would be utilized as major tools to visualize paths in real-time and to select alternative path when failure or audition of route node occurs.

• The Journal of Engineering Geology
• /
• v.4 no.2
• /
• pp.169-186
• /
• 1994

A GIS technique was developed for aggregate resources management and transport route analysis. In the study, the management of aggregate resources deals with resources evaluation and control of aggregate supply. The computer system was specially designed for this analysis on the basis of relational database model, and it was named ARIS(Aggregate Resources Information System). A Vector database for this study area of Chungcheong - Do was established for analysis of ARIS. In network analysis, there are many essential elements such as road name, speed limit and width, turns and stops etc. Impedance was also measured for the resistance against transportation of aggregate resources. Actually, the impedances are attributes of arcs, turns and stops. Finally, the feasibility of ARIS was tested to use as a decision making tool of aggregate resources management.

• Korean Journal of Construction Engineering and Management
• /
• v.8 no.6
• /
• pp.129-138
• /
• 2007

According to the preceding research outcomes, feasibility studies on public construction projects were incorrect and subjective. To resolve the problems, Korean government initiated Preliminary Feasibility Study (PFS) system prior to undertaking the main feasibility study. The PSF can be categorized into four areas such as road, railroad, harbor, airport, and Culture & Tourism (C&T). Especially when it comes to complex due to the introduction of five-weekday working system and local $government^{\circ}{\phi}s$ self administrative system. As a result, the standardization and legislation of the PSF can not be operated effectively. Accordingly this paper seeks to 1) identify actual condition of conducted PSF in C&T; 2) set up analytical model considering cost factor of economical efficiency and seek obstacles of PSF system; 3) suggest improvement plan for construction PSF projects.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.28 no.2
• /
• pp.69-74
• /
• 2015

Recently, energy harvesting technology is increasing due to the fossil fuel shortages. Energy harvesting is generating electrical energy from wasted energies as sunlight, wind, waves, pressure, and vibration etc. Energy harvesting is one of the alternatives of fossil fuel. One of the energy harvesting technologies, the piezoelectric energy harvesting has been actively studied. Piezoelectric generating uses a positive piezoelectric effect which produces electrical energy when mechanical vibration is applied to the piezoelectric device. Piezoelectric energy harvesting has an advantage in that it is relatively not affected by weather, area and place. Also, stable and sustainable energy generation is possible. However, the output power is relatively low, so in this paper, newly designed honeycomb shaped piezoelectric energy harvesting device for increasing a generating efficiency. The output characteristics of the piezoelectric harvesting device were analyzed according to the change of parameters by using the finite element method analysis program. One model which has high output voltage was selected and a prototype of the honeycomb shaped piezoelectric harvesting device was fabricated. Experimental results from the fabricated device were compared to the analyzed results. After the AC-DC converting, the power of one honeycomb shaped piezoelectric energy harvesting device was measured 2.3[mW] at road resistance 5.1[$K{\Omega}$]. And output power was increased the number of harvesting device when piezoelectric energy harvesting device were connected in series and parallel.

• The Journal of the Korea Contents Association
• /
• v.4 no.2
• /
• pp.7-12
• /
• 2004

The technique of birdeye image generation of terrain through the use of satellite digital images and digital maps are very important elements and have applications in fanning establishment as well as the actual design of several construction works in complex fields. This paper studies stereo perspective image generation as a possibility through 3-dimensional analysis combined with digital elevation data and remotely sensed images. For this, first of all, ortho-images generated by very accurate GCP and DEM from contour file makes 3-dimensional terrain analysis possible and allows stereo­viewing at the highway construction planning sites. So, we developed the technical methods for the 3-dimensional approach on the planning sites of highways by use of perspective orthoimages. From this research, diverse terrain analysis is possible through stereo perspective image generation, and can leads to various application in road construction through gain study results from access to realtime virtual spatial on the objects area in korea.

• Journal of the Korean Society for Railway
• /
• v.12 no.4
• /
• pp.499-505
• /
• 2009

This paper evaluated applicability of railroad reference points for determinating geoid heights. For this research, reference points on the Honam express raildroad which contain ellipsoid heights estimated by GPS/Leveling and orthometric heights by leveling were used. Geoid heights were calculated uisng orthometric and ellipsoid heights of 360 railroad reference points, and the RMSE's with respect to different intervals of reference points were analysed which were induced by interpolation methods. The results showed that no significant difference of RMSE's among interpolation. methods. RMSE's of 0-4km interval of reference points were determined within 2cm and 5-8km were within 3cm. Also, this research confirmed that GPS leveling with Geoid model is not auurate enough to be used for railroad surveying as yet.

• Journal of Korean Society for Geospatial Information Science
• /
• v.1 no.1 s.1
• /
• pp.117-125
• /
• 1993

GSIS is a system that contains spatially referenced data that can be analyzed and converted to information for a specific set of purpose, or application. The key feature of a GSIS is the analysis of data to produce new information. The current emphasis in the transportation is to implement GSIS in conjunction with real time systems Requirements for a transportation GSIS are very different from the traditional GSIS software that has been designed for environmental and natural resource applications. A transportation GSIS may need to include the ability for franc volume, forecasting, pavement management A regional transportation planning model is actually a set of models that are used to inventory and then forecast a region's population, employment, income, housing and the demand of automobile and transit in a region. The data such as adminstration bound, m of landuse, road networks, location of schools, offices with populations are used in this paper. Many of these data are used for analyzing of traffic volume, traffic demand, time of mad construction using GSIS.

• Asian Journal of Atmospheric Environment
• /
• v.2 no.1
• /
• pp.34-46
• /
• 2008

Emissions inputs for use in air quality modeling of Korea were generated with the emissions inventory data from the National Institute of Environmental Research (NIER), maintained under the Clean Air Policy Support System (CAPSS) database. Source Classification Codes (SCC) in the Korea emissions inventory were adapted to use with the U.S. EPA's Sparse Matrix Operator Kernel Emissions (SMOKE) by finding the best-matching SMOKE default SCCs for the chemical speciation and temporal allocation. A set of 19 surrogate spatial allocation factors for South Korea were developed utilizing the Multi-scale Integrated Modeling System (MIMS) Spatial Allocator and Korean GIS databases. The mobile and area source emissions data, after temporal allocation, show typical sinusoidal diurnal variations with high peaks during daytime, while point source emissions show weak diurnal variations. The model-ready emissions are speciated for the carbon bond version 4 (CB-4) chemical mechanism. Volatile organic carbon (VOC) emissions from painting related industries in area source category significantly contribute to TOL (Toluene) and XYL (Xylene) emissions. ETH (Ethylene) emissions are largely contributed from point industrial incineration facilities and various mobile sources. On the other hand, a large portion of OLE (Olefin) emissions are speciated from mobile sources in addition to those contributed by the polypropylene industry in point source. It was found that FORM (Formaldehyde) is mostly emitted from petroleum industry and heavy duty diesel vehicles. Chemical speciation of PM2.5 emissions shows that PEC (primary fine elemental carbon) and POA (primary fine organic aerosol) are the most abundant species from diesel and gasoline vehicles. To reduce uncertainties in processing the Korea emission inventory due to the mapping of Korean SCCs to those of U.S., it would be practical to develop and use domestic source profiles for the top 10 SCCs for area and point sources and top 5 SCCs for on-road mobile sources when VOC emissions from the sources are more than 90% of the total.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.14 no.6
• /
• pp.21-36
• /
• 2015

These days Automated Vehicle(AV) has been receiving attention as a fundamental solution to resolve the various transportation problems and various researches related to the benefits of AV have been done. However, previous researches mainly analyzed the effects in the virtual network. The purpose of this research is to predict and to find out the benefits by introducing the Automated Vehicle to present road traffic system. Thus, the study analyzes the traffic-flow changes of Gyeongbu freeway Seoul-Singal basic section which is planned for setting the test-bed. The results show that Automated Vehicle can have negative effects on the traffic-flow in low volume of LOS A and B. However, the average speed increases and the traffic density decreases in more than LOS C, the traffic volume increase. Therefore, the introduction of Automated Vehicle achieves positive effect on various transportation problems such as the traffic congestion.