• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.6
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• pp.73-80
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• 2017

The objective of this study is to investigate whether the daily rainfall depth derived from daily data represents the event rainfall depth derived from hourly data. For analysis, the 85th, 90th, and 95th percentile daily rainfall depths were first computed using daily rainfall data (1986~2015) collected at 63 weather stations. In addition, the storm event was separated by the interevent time definition (IETD) of 6, 12, 18, and 24 hr using hourly rainfall data. Based on the separated storm events, the 85th, 90th, and 95th percentile event rainfall depths were calculated and compared with the using hourly rainfall data with the 85th, 90th, and 95th percentile daily rainfall depths. The event rainfall depths computed using the IETD were greater than the daily rainfall depths. The difference between the event rainfall depth and the daily rainfall depth affects the design and size of the facility for controlling the stormwater. Therefore, the designer and policy decision-maker in designing the stormwater best management practices need to take into account the difference generated by the difference of the used rainfall data and the selected IETD.

• International Journal of Highway Engineering
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• v.19 no.2
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• pp.1-6
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• 2017

PURPOSES : Pavement textures can be categorized into four according to wavelength: microtexture, macrotexture, megatexture (roads), and roughness. Pavement surface texture influences a number of aspects of tire-pavement interaction such as wet-weather friction, tire-pavement noise, splash, spray, tire-wear, and rolling resistance. In particular, macrotexture is the pavement surface characteristic that considerably impacts tire-pavement noise. In general, it can be demonstrated that tire-pavement noise increases with the increase of texture depth and wavelength. Recently, mean profile depth (MPD) and wavelength have been used to evaluate tire-pavement noise. This study aimed to identify the relationship between mean profile depth and average wavelength for asphalt pavement based on the information obtained on a number of asphalt pavement sections. METHODS : Profile data were collected from a number of expressway sections in Korea. In addition, mean profile depth and average wavelength were calculated by using this profile data. Statistical analysis was performed to determine the correlationship between mean profile depth and average wavelength. RESULTS:This study demonstrates a linear relationship between mean profile depth and average wavelength for asphalt concrete pavement. CONCLUSIONS :The strong relationship between mean profile depth and average wavelength of asphalt pavement was determined in this study.

• Advances in robotics research
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• v.2 no.1
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• pp.33-44
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• 2018

This paper presents a novel feature detection algorithm called depth-hybrid speeded-up robust features (DH-SURF) augmented by depth information in the speeded-up robust features (SURF) algorithm. In the keypoint detection part of classical SURF, the standard deviation of the Gaussian kernel is varied for its scale-invariance property, resulting in increased computational complexity. We propose a keypoint detection method with less variation of the standard deviation by using depth data from a red-green-blue depth (RGB-D) sensor. Our approach maintains a scale-invariance property while reducing computation time. An RGB-D simultaneous localization and mapping (SLAM) system uses a feature extraction method and depth data concurrently; thus, the system is well-suited for showing the performance of the DH-SURF method. DH-SURF was implemented on a central processing unit (CPU) and a graphics processing unit (GPU), respectively, and was validated through the real-time RGB-D SLAM.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.1
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• pp.65-71
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• 2008

This study collected the latest 30-year (1976~2005) continuous rainfall data hourly recorded at 61 meterological observatories in Korea, and the continuous rainfall data was divided into individual rainfall events. In addition, distribution charts of average rainfall event-depth were created to facilitate the application to the overflow risk-based design of detention storage basin. This study shows that 4 hour is appropriate for SST (storm separation time) to separate individual rainfall events from the continuous rainfall data, and the one-parameter exponential distribution is suitable for the frequency distribution of rainfall event depths for the domestic rainfall data. The analysis of the domestic rainfall data using SST of 4 hour showed that the individual rainfall event was 1380 to 2031 times, the average rainfall event-depth was 19.1 to 32.4mm, and ranged between 0.877 and 0.926. Distribution charts of average rainfall event-depth were created for 4hour and 6 hour of SST, respectively. The inland Gyeongsangbuk-do, Western coastal area and inland of Jeollabuk-do had relatively lower average rainfall event-depth, whereas Southern coastal area, such as Namhae, Yeosu, and Jeju-do had relatively higher average rainfall event-depth.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.4
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• pp.560-566
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• 2010

Port of Samcheonpo, designated as a Trading Port, is constructing New Port for the increase in trade and the requirement of maritime safety is growing. To meet these requirement for maritime safety, hydrographic surveying around south sea area of Samcheonpo using Multibeam Echo Sounder(MBES), DGPS etc was conducted. In this study, major item of hydrographic surveying such as sounding data was acquired and analyzed depth data comparing with vertical uncertainty in the special publication for hydrographic minimum specification published in Feb, 2008 by International Hydrographic Organization. By analyzing the depth data with 3 steps procedure, the port and starboard beam by removing the outskirts of the data processing could improve the efficiency and accuracy. The error of south sea were about 0.2m and the upper central part of the error were within 0.2m. Depth data of the study area are included in the 99% of 1st order and satisfied with a 100% tolerance of special order based on the international hydrograhic survey standard. This study will be a good case to support efficient decision-making for safe navigation, coastal management.

• Journal of The Korea Institute of Healthcare Architecture
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• v.22 no.4
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• pp.47-55
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• 2016

Purpose: Growth and change are the most important things in planning of hospital architecture. It is especially necessary for countless changes taken place since the hospital opens to be adapted to the planning of hospital architecture phase. The space depth in the hospital serves a very crucial role in accepting these changes. The purpose of this study is to provide basic data necessary to space depth planning to prepare for change through analyzing space depth's change in hospital architecture chronologically. Methods:: The method of this study is analyzing space depth's change in cases of 19 hospitals in total, from the 1980's, which is the quantitative growth period, until recently. Especially this study is analyzing Max & Min space depth focusing change of medical environment. Based on this, this study suggests an form of space depth and optimum range of space depth response to growth and change of hospital architecture. Results: The conclusions of this study are as follows. Considering these conclusion, double linear system is most appropriate for space depth for hospital architecture planning focused on system. Optimal range of space depth is at least 21.6m or more in case of clinic room and from 27 meter to 37meter in case of examination & treatment room. Implications: Space of Depth is a key element determining system for hospital architecture planning focused on system. The results of this paper can be data for planning system of hospital architecture which copes with the change.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.7
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• pp.930-937
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• 2011

The characteristics of mean velocity and turbulence have been analyzed in the circular open channel flow using PIV measurement data for a wide range of water depth. The measured data are fitted to a velocity distribution function over the whole depth of the open channel. Reynolds shear stress and mean velocity in wall unit are compared with the analytic models for fully-developed turbulent boundary layer. Both the mean velocity and Reynolds shear stress have different distributions from the two-dimensional boundary layer flow when the water depth increases over 50% since the influence of the side wall penetrates more deeply into the free surface. The cross-stream Reynolds normal stress also has considerably different distribution in view of its peak value and decreasing rate in the outer region whether the water depth is higher than 50% or not.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.815-816
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• 2008

In this paper, we evaluate depth image preprocessing for 3D data service based on DIBR over T-DMB. We evaluate two preprocessing methods of depth images. These are gaussian smoothing and adaptive smoothing. The results show that adaptive smoothing is more suitable for images with sharp transition of depth.

• Water for future
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• v.20 no.1
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• pp.55-61
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• 1987

This Study is to estimate depth-length ratios by the frequency analysis of simultaneous rainfall data on fixed points in the Han -River basin. The depth-length ratios are based on examination of spatial and temporal correlation structures of the Han-River basin's rainfall. This Study reveals that the depth-length ratios are decreasing as the distance of the basin increases and that they are increasing as the duration of rainfall increases. This study also shows that the ratios tend to decrease as the return period increase. The results present general equations and characteristic equations of depth-length ratios, figures and characteristic parameter tables which explain the temporal and spatial structures of rainfall in the Han-River basin.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.212-217
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• 1993

In this paper, the hardening depth in Laser surface hardening process is estimated using a multilayered neural network. Input data of the neural network are surface temperature of five points, power and travelling speed of Laser beam. A FDM(finite difference method) is used for modeling the Laser surface hardening process. This model is used to obtain the network's training data sample and to evaluate the performance of the neural network estimator. The simulational results showed that the proposed scheme can be used to estimate the hardening depth on real time.