PURPOSES : This study aims to investigate the reliability of the real-time estimation of intersection traffic volumes based on the integration of location intelligence data and smart intersection data. METHODS : Location intelligence data (LID) and smart intersection data were obtained at eight intersections in Inju-daero, Incheon. The two datasets were then integrated to estimate traffic volumes for intersections in the shadow section, where traffic information was not expected to be obtained. The traffic estimation accuracy was evaluated using the total traffic, approach traffic, and turning movement volumes at the intersections. The estimated traffic was compared with the actual traffic volumes in the smart intersection data to validate the reliability of traffic estimation. RESULTS : The average traffic estimation error for the total intersection volume was approximately 4.5% for the five intersections in the shadow section. The estimation errors for the approach volumes (less than 5%) were also consistently low, except from 12 pm to 1 pm. CONCLUSIONS : The findings of this study suggest that location intelligence data can be combined with smart intersection data to estimate real-time traffic for shadow sections on roadways. This could enable a cost-effective cooperative intelligent transport system (C-ITS) when the municipal budget is limited, ultimately leading to the sustainable operation of C-ITS.
This study aims to investigate and reveal the spatial structure of Boryeonghyeon by examining the geographical status of its Eupchi (Local administrative center:邑治) through an analysis of the location, tracing locations of governemnt offices including Dongheon(東軒) and Kaeksa(客舍) in the walled town, and checking the lot numbers of Sajikdan(社稷壇), Yeodan(厲壇), and Cheongyeonyeok(靑淵驛) outside it. Buildings of Boryeonghyeon in the walled town in the Joseon Dynasty were almost lost and now, part of the city wall and Haesanru(海山樓) just remains as relic. The walled town consisted of several buildings of government offices as well as Dongheon and Kaeksa which are government organs. Altar and shrine(壇廟) facilities including Shrine of Confucius(文廟), Altar of Land and Grain, and Preceptor's Shrine were placed outside the walled town and Cheongyeonyeok were operated as the facilities for transmission of royal orders. Therefore, the government office facilities in the walled town, altar and shrine facilities outside the fortress, and the location of the post station were required to trace and check each of them. For the checking method, the lot numbers could be checked by checking the original cadastral maps and the then land categories and owners, analyzing the records and circumstances of the relevant township annals(邑誌), and examining analyses on the locations by using a numerical map of one to 5 thousands. The study estimated the locations of government facilities including Dongheon and Kaesa placed in the walled town and was grasped to be the east and west gates with the south gate which remains now in the fortress. And the lot numbers of Sajikdan, Yeodan, Cheongyeonyeok.
The LBS(Location Based Service) technology plays an important role in reducing wastes of time, losses of human lives and economic losses by detecting the user's location in order by suggesting the optimal evacuation route of the users in case of safety accidents. We developed an algorithm to estimate indoor location, movement path and indoor location changes of smart phone users based on the built-in sensors of smartphones and the dead-reckoning algorithm for pedestrians without a connection with smart devices such as Wi-Fi and Bluetooth. Furthermore, seven different indoor movement scenarios were selected to measure the performance of this algorithm and the accuracy of the indoor location estimation was measured by comparing the actual movement route and the algorithm results of the experimenter(pedestrian) who performed the indoor movement. The experimental result showed that this algorithm had an average accuracy of 95.0%.
In this study, the leak signal was measured by using an accelerometer to analyze the basic data and methodology for the development of the leak point estimation method in the water supply pipe. The measured results were analyzed by frequency analysis and cross-correlation analysis for leakage signals, and the error range was compared and analyzed with the actual leak point distance. As a result, it was confirmed that the vibration intensity due to leakage from the water leakage point was attenuated according to the distance. In the case of the ductile iron casting used in the experiment, the intensity of the signal at the 945 Hz, 1,500 Hz, 2,300 Hz band was increased with the change of the pressure in the pipe at 4mm of leakage hole. Also, it was confirmed that as the water pressure increases, the intensity of the leak signal increases but the similarity of the signal decreases. The results of this study confirm that the accelerometer sensor can be used efficiently for leak detection and it can be used as a basic data for the analysis for the development of leak point estimation method in the future.
The Location Based Service is growing rapidly nowadays due to the universalization of the use for smartphone, and therefore the location determination technology has been placed in a very important position. this study suggests an algorithm that can provide the estimate of users' location by using smartphone sensors. And in doing so we will propose a methodology for the creation and update of indoor map though the more accurate position estimation using smartphone sensors such as acceleration sensor, gyroscope sensor, geomagnetic sensor and rotation sensor.
Through Estimation of stress distribution, both value and location of the maximum stress can be found. and the maximum stress is very important indicator for structural safety evaluation. In this connection, a lot of studies to estimate stress distributions are conducted. But studies on the optimal number and location of measurement points are few. So, In this study, the effects of the number and location of measurement points on the estimation stress distribution for the steel beam structure using motion capture system and cubic smoothing spline interpolation are researched.
As the building maintenance and safety management have recently been brought to attention, the utilization of non-destructive testing methods for internal inspection of concretes is increasing. Non-destructive testing methods, unlike typical destructive testing methods that deconstruct or cut the building in case of issues such as pores, heterogeneous material, cracks or any such equivalent issues inside/outside the building, refer to the testing methods for pores, heterogeneous material, or defectiveness occurring in the specimen without changes or destruction of internal structure using ultrasound, radiation, electromagnetism, fluid, heat, or light. In this study, among such non-destructive testing methods, the impact echo method was used for an experiment to estimate the steel rebar location and thickness in the concrete mock member.