• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.4
• /
• pp.175-182
• /
• 2021

As road noise became an issue, low-noise pavement (LNP) has emerged. The noise difference from general asphalt pavement (GAP) is a measure to explain the noise reduction of LNP. On the other hand, even for GAP, noise varies with the performance years (PY) and pavement condition. This study evaluated the representative noise value (RNV) by the speed and PY of GAP. Sections of 49selected from the National Road Pavement Management System, and the noise was measured at speeds from 50km/h to 80km/h at every 10km/h using the Close Proximity Method (CPX). Because the noise immediately after construction differed from the other, it was treated separately, and some outliers were removed. The noise increased with increasing PY. In addition, the noise increase by speed showed a reliable trend at all noise levels. The RNV for each speed and PY was obtained through analyses of the PY and speed. The average noise difference between the initial construction and the six-year-paced pavement was approximately 6dB. When evaluating the noise reduction of LNP, it is necessary to use RNV rather than the noise of old pavement. The RNV of GAP is necessary for a relative comparison with LNP and studying the road noise characteristics for each GAP type.

• Journal of Climate Change Research
• /
• v.6 no.4
• /
• pp.291-302
• /
• 2015

Vulnerability due to climate change depends on the concentration of carbon dioxide emissions over several upcoming decades. The objective of this study is to estimate the concentration of greenhouse gases and air pollutants in 2100, while also accounting for expected socio-economic changes in Korea. First, we intend to prepare scenarios for possible socioeconomic changes in Korea: business as usual (BAU), high growth and low growth. Secondly, we aim to predict services demands in residential?commercial sector, transportation sector, industrial sector for each scenarios. Finally, the emissions of LLGHG and SLCP will be estimated on the basis of the predicted service demands. The study results project that in Korea, LLGHG emissions will be approximately $660Mt\;CO_2\;eq$. and SLCP emissions will be approximately 3.81 Mt, -including black carbon (BC) by 2100. The transportation and industrial sectors are the major source for LLGHG emissions, and the residential and commercial sector serve as the SLCP source. Later, additional studies on the cost and benefit of mitigation should be carried out by comparing the reduced use of materials that cause climate change as a result of reduction policies and the socioeconomic cost.

• The Journal of Engineering Geology
• /
• v.28 no.4
• /
• pp.605-618
• /
• 2018

Korea follows the slope design criteria during construction. It was enacted by the Ministry of Land, Transport and Maritime Affairs. There are cases where the Soil-nail is designed as a measure to secure slope stability. The arrangement of the soil-nail may be arranged at equal intervals or may be arranged differently depending on the soil failure model. The optimum design of the countermeasure method is determined by securing stability of the slope through optimization of dimensions and shape. However, when uniform nails are placed at low elevations in slopes, the standard safety factor is exceeded, which may hinder economic design. It is preferable to arrange the reinforcement of the nails over the entire slope. When the horizontal spacing of the nails was topology optimized according to the slope height, it was possible to minimize the amount of reinforcement while satisfying the standard safety factor. Since the active load is reduced in the section where the slope height is lowered, the safety factor after reinforcement may be excessively increased. Therefore, the phase optimization method is proposed as an economical optimal design method using the reinforcing shape density. In addition, a relational expression was designed to optimize the horizontal spacing by slope height.

• Journal of the Health Care and Life Science
• /
• v.8 no.2
• /
• pp.155-163
• /
• 2020

The purpose of this study is to examine the current status of the Injury based on the 7th National Data on the National Health and Nutrition Survey, identify the relationship between general characteristics, safety awareness, health status, injury, and identify the factors that affect the occurrence of injury. The subjects were selected for the final analysis of 1,608data. For the analysis, frequency analysis, cross analysis, and multiple logistic regression analysis were performed. the results of the study show that in the young-old elderly, gender(woman), marital status(separated of divorced), lower the awareness of safety, body discomfort, sickness, and in-outpatient, Annual unmet medical service experienced are higher the occurrence of injury. Therefore, as a prevention education that lowers the incidence of injury. selective education is required for the Young-old and Old-old elderly, and legal penalties for drunk driving on various means of transportation and an integrated approach to strengthening and education is required.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.39 no.3
• /
• pp.141-148
• /
• 2021

This paper presents a method to detect zebra-crossing using deep learning which combines SegNet and ResNet. For the blind, a safe crossing system is important to know exactly where the zebra-crossings are. Zebra-crossing detection by deep learning can be a good solution to this problem and robotic vision-based assistive technologies sprung up over the past few years, which focused on specific scene objects using monocular detectors. These traditional methods have achieved significant results with relatively long processing times, and enhanced the zebra-crossing perception to a large extent. However, running all detectors jointly incurs a long latency and becomes computationally prohibitive on wearable embedded systems. In this paper, we propose a model for fast and stable segmentation of zebra-crossing from captured images. The model is improved based on a combination of SegNet and ResNet and consists of three steps. First, the input image is subsampled to extract image features and the convolutional neural network of ResNet is modified to make it the new encoder. Second, through the SegNet original up-sampling network, the abstract features are restored to the original image size. Finally, the method classifies all pixels and calculates the accuracy of each pixel. The experimental results prove the efficiency of the modified semantic segmentation algorithm with a relatively high computing speed.

• Journal of Advanced Navigation Technology
• /
• v.25 no.1
• /
• pp.1-7
• /
• 2021

Detect and avoid (DAA) system, which is essential for the operation of UAS, detects intruding aircraft and offers the ranges of turn and climb/descent maneuver that are required to avoid the intruder. This paper uses detect and avoid alerting logic for unmanned systems (DAIDALUS) developed at NASA as a DAA algorithm. Since DAIDALUS offers ranges of avoidance maneuvers, the actual avoidance maneuver must be decided by the UAS pilot as well as the timing and method of returning to the original route. It can be readily used in real-time human-in-the-loop (HiTL) simulations where a human pilot is making the decision, but a pilot decision model is required in fast-time simulations that proceed without human pilot intervention. This paper proposes a pilot decision model that maneuvers the aircraft based on the DAIDALUS avoidance maneuver range. A series of tests were conducted using test vectors from radio technical commission for aeronautics (RTCA) minimum operational performance standards (MOPS). The alert levels differed by the types of encounters, but loss of well clear (LoWC) was avoided. This model will be useful in fast-time simulation of high-volume traffic involving UAS.

• Journal of Wetlands Research
• /
• v.23 no.1
• /
• pp.85-93
• /
• 2021

Sewage separation which often involves installing a new pipe to separate wastewater flow from stormwater runoff flow can be costly and depends highly on its feasibility in a site. To be able to develop a potentially more economical alternative that can also lessen major road traffic disturbance during this process, a different approach where a smaller sewage separator pipe is installed inside an existing combined sewer pipe was investigated. A small-scale of a box sewer and the proposed sewage separator pipe was constructed in the laboratory to observe and compare the deposition of solids and other solid-associated major pollutants at different flow rates. In addition, three-dimensional flow simulations considering five different scenarios were conducted using Ansys Fluent to observe the effect of the proposed sewage separator pipe to the hydraulic flow if installed inside the combined sewer pipe. Results revealed that the deposition of TSS, TCOD, TN, and TP were reduced by at least 60% when the wastewater was conveyed by the sewage separator pipe instead of the combined sewer pipe. Moreover, the flow simulations conducted showed that there was little to no major disturbance in hydraulic flow and velocity distribution when the sewage separator was installed inside a straight pipe and even at pipe transitions such as intersections, turns, and drop in elevation. Considering the pipe dimensions and the results of the study, the proposed approach can be promising in terms of reduction in pollutant deposition without a major effect on the hydraulic flow. Further investigation and cost-analysis should be done in the future to support these preliminary findings and help alleviate the problems caused by combined sewer overflows by introducing an alternative approach.

• The Journal of the Korea Contents Association
• /
• v.21 no.8
• /
• pp.424-441
• /
• 2021

The research is to analyze current situation of the coordinated development of "5 Region" and "4 Road" in Henan Province and put forward problems about the coordinated development of the "5 Region" and "4 Road" with the inland geographical location in China by drawing on the experience of the coordinated development of related industries in developed countries and regions based on China's "One Belt And One Road". According to the problems, a plan for the promotion of opening up to the outside world is provided. Through research, the following problems are found: First, the superposition advantage of five districts' and "four roads' has not been fully brought into play. Second, the collaborative linkage mechanism is not sound. Third, modern comprehensive transportation hub facilities are not fully completed. Fourth, the industrial support capacity is insufficient. Fifth, basic support is difficult to meet the needs of future development. The plan is as follows: First, building a top-level strategic platform and improve the policy support system. Second, we need to enhance the advantages of the four Silk Roads and accelerate their interconnected development. Third, establishing a coordination and mutual assistance mechanism to stimulate the superposition effect of industrial clusters. The significance of this study is that it can be used as research data to predict the future direction of China's "One Belt and One Road" policy and enlightenment to stimulate the economic revitalization of inland provinces.

• Journal of Korean Society of Disaster and Security
• /
• v.14 no.1
• /
• pp.1-8
• /
• 2021

A corrugated pipe is widely used in firefighting equipment and sprinkler pipes because of its elasticity, which is less damaged by deformation and convenient facilities. However, the corrugated shape of the wall results in complex internal turbulent flow, and it is difficult to predict the pressure drop, which is an important design factor for pipe flow. The pressure drop in the corrugated tube is a function of the shape factors of the pipe wall, such as groove height, length, and pitch. Existing studies have only shown a study of pressure drop due to length changes in the case of D-shaped tubes with less than 5 pitch (P) and height (K) of the rectangular grooves in the tube. In this work, we conduct a numerical study of pressure drop for P/Ks with length and height changes of 2.8, 3.5 and 4.67 with Re Numbers of 55,000, 70,000 and 85,000. The pressure drop in the corrugated tube was interpreted to decrease with smaller P/K. We show that the pressure drop is affected by the change in the groove aspect ratio, and the increase in the height of the groove increases the recirculation area, and the larger the Reynolds number, the greater the pressure drop.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.20 no.6
• /
• pp.133-146
• /
• 2021

Providing weather information on roads today means that the road weather conditions near weather observation points are presented to road managers and road users. These weather observation points are managed by the Korea Meteorological Administration. However, it is difficult to provide accurate weather information due to physical limitations such as the presence of precipitation collection points, distance to weather information provision roads, and the presence of mountains. Therefore, this study intends to perform a comparative analysis by time zone and administrative dong provided by the Meteorological Administration using the wiper information among the information contained in the PVD(Probe Vehicle Data) collected from the highway C-ITS project. As a result of the analysis it was possible to detect rainfall even in the event of local rainfall and rainfall over a long period of time and the higher the cumulative precipitation per hour, the higher the probability of coincidence. This study is meaningful because it used PVD to solve the limitations of the existing road weather information provision method and suggested utilization plan for PVD.