• Journal of Multimedia Information System
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• v.2 no.4
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• pp.303-310
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• 2015

Vulnerable road users such as bike, motorcycle, small automobiles, and etc. are easily attacked or threatened with bigger vehicles than them. So this paper suggests a new approach two-wheelers detection system riding on people based on modified histogram of oriented gradients (HOGs) which is weighted by curvature and local correlation coefficient. This correlation coefficient between two variables, in which one is the person riding a bike and other is its background, can represent correlation relation. First, we extract edge vectors using the curvature of Gaussian and Histogram of Oriented Gradients (HOG) which includes gradient information and differential magnitude as cell based. And then, the value, which is calculated by the correlation coefficient between the area of each cell and one of bike, can be used as the weighting factor in process for normalizing the HOG cell. This paper applied the Adaboost algorithm to make a strong classification from weak classification. The experimental results validate the effectiveness of our proposed algorithm show higher than that of the traditional method and under challenging, such as various two-wheeler postures, complex background, and even conclusion.

• KCID journal
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• v.13 no.2
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• pp.283-292
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• 2006

The characteristics of nonpoint source pollutant loads in upstream of Nakdong River were studied through analysis of pollutant loads of 10 sub-watersheds divided based on administrative district. The discharge and pollutant concentration of each sub-watershed were collected from Nakdong-River Water Research Institute and Daegu Regional Environmental office, respectively. Pollution items analysed in this study were BOD, T-N and T-P. The delivery loads of the nonpoint source pollutions of each sub-watershed were calculated after analysing the concentration of the pollution of each site. Several points were found from the results. Firstly, in general, city areas including Sangju, Andong showed higher degree of nonpoint pollution than country areas including Cheongsong, Yeongyang. The sub-watersheds located upstream side, such as Yeongju, Bonghwa, Necessarily show better water quality than the sub-watersheds located downstream side, such as Mungyeong, Uiseong. This result indicates that a given pollution condition within the watershed can be more sensitive than location factor to the level of water quality. Secondly, the delivery load and area of watershed were not necessarily correlated in the sense of water quality, while the discharge was shown to be highly correlated to the delively load of pollution. Lastly, sewage and waste caused from population and livestock, as well as landuse factor, were found to significantly contribute to the water pollution. Alternative solutions for controlling pollution source, therefore, should be provided to meet target levels of water quality in these regions.

• Korea-Australia Rheology Journal
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• v.21 no.3
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• pp.193-200
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• 2009

We present a direct simulation technique for two-dimensional mold-filling simulations of fluids filled with a large number of circular disk-like rigid particles. It is a direct simulation in that the hydrodynamic interaction between particles and fluid is fully considered. We employ a pseudo-concentration method for the evolution of the flow front and the DLM (distributed Lagrangian multipliers)-like fictitious domain method for the implicit treatment of the hydrodynamic interaction. Both methods allow the use of a fixed regular discretization during the entire computation. The discontinuous Galerkin method has been used to solve the concentration evolution equation and the rigid-ring description has been introduced for freely suspended particles. A buffer zone, the gate region of a finite area subject to the uniform velocity profile, has been introduced to put discrete particles into the computational domain avoiding any artificial discontinuity. From example problems of 450 particles, we investigated the particle motion and effects of particles on the flow for both Newtonian and shear-thinning fluid media. We report the prolonged particle movement toward the wall in case of a shear-thinning fluid, which has been interpreted with the shear rate distribution.

• Journal of the Korean Society of Visualization
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• v.10 no.1
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• pp.47-54
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• 2012

Single Stage To Orbit (SSTO) missions which require its engines to be operated at varying back pressure conditions, use engines operate at high combustion chamber pressures (more than 100bar) with moderate area ratios (AR 70~80). This ensures that the exhaust jet flows full during most part of the operational regimes by optimal expansion at each altitude. Aero-spike nozzle is a kind of altitude adaptation nozzle where requirement of high combustion chamber pressures can be avoided as the flow is adapted to the outside conditions by the virtue of the nozzle configuration. However, the thrust prediction using the conventional thrust equations remains to be a challenge as the nozzle plume shapes vary with the back pressure conditions. In the present work, the performance evaluation of a new aero-spike nozzle is being carried out. Computational studies are carried out to predict the thrust generated by the aero-spike nozzle in varying back pressure conditions which requires the unsteady pressure boundary conditions in the computational domain. Schlieren pictures are taken to validate the computational results. It is found that the flow in the aero-spike nozzle is mainly affected by the base wall pressure variation. The aerospike nozzle exhibits maximum performance in the properly expanded flow regime due to the open wake formation.

• Journal of Korean Society on Water Environment
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• v.33 no.1
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• pp.97-106
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• 2017

In this study, the characteristics of nonpoint source pollutant loads from separate sewer overflow (SSO) and combined sewer overflow (CSO) were evaluated during 2016 in Namyangju city, Korea. Five rainfall events were monitored during 2016 with ranging from 14.5 mm to 121.5 mm. The runoff ratio of CSO was higher than that of SSO because only design volume of maximum sanitary sewer ($1Q_h$) was transported and treated and $2Q_h$ was overflowed to waterbody during rainy day although combined sewer system was designed to transport $3Q_h$ to treatment system. The event mean concentrations (EMCs) and pollutant loads from CSO were higher than those from SSO. BOD and COD of CSO, and TOC and TN of SSO represented distinct first flush phenomena. The inadequate management in combined sewer system from which the untreated $2Q_h$ from CSO was overflowed to waterbody during rainy day could influence on high pollutant loads and first flushing. Treating $2Q_h$ from CSO, source control such as low impact development, and treating outflow from SSO were strongly recommended to control non-point source pollution in urban area.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.74-83
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• 2007

The goal of this study is to establish an integrated watershed hydrologic model for the whole Nakdong River basin whose area is an approximately 24,000 km2. Including a number of watershed elements such as rainfall, runoff, water use, and so on, the proposed model is based on SWAT model, and is used to improve the flow duration curve estimation of ungauged watersheds for Korean Total Maximum Daily Load (TMDL). The model is also used to recognize quantitatively the river flow variation due to water use elements and large dam effluents in the whole watershed. The established combined watershed hydrologic model, SWAT-Nakdong, is used to evaluate the quantified influences of artificial water balance elements, such as a dam and water use in the watershed. We apply two water balance scenarios in this study: the dam scenario considering effluent conditions of 4 large multi-purpose dams, Andong dam, Imha dam, Namgang dam, and Habcheon dam, and the water use scenario considering a water use for stream line and the effluent from a treatment plant. The two scenarios are used to investigate the impacts on TMDL design flow and flow duration of particular locations in Nakdong River main stream. The results from this study will provide the basic guideline for the natural flow restoration in Nakdong River.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.5
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• pp.1558-1563
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• 2010

This paper describes a study on algorithm for the development of machine vision system as well as the inspection of automobile's plastic part locking lever to replace a human worker's eye inspection. Before developing the machine vision system based on the PC, the purpose of this research is to develop the algorithm to decide whether a product is a good/bad one in real time inspection. NI-LabVIEW software is used in the inspection method and an inspection program is developed using LabVIEW Vision image functions. The inspection program was built and validated to help the system operator set up the inspection area and change the criteria number in the program.

• The Journal of Korean Physical Therapy
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• v.8 no.1
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• pp.81-89
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• 1996

This study is to make legal suggestions concerning the legal status of the physical therapists and the their clinics io Korea. This study compares the legal status of the physical therapists with that of the optical and dental technicians, and reviews the current system of the American physical therapeutic clinic. 1. Under the supervision of the doctor or dentist' in Article 1 of Law concerning the Medical Technician should be deleted or changed into 'by the request of the doctor or dentist'. A new independent law should be mode only fer the physical therapist from the general law that stipulates the legal status of other similar medical technicians. 3. The legal status of the physical therapeutic clinic should be stipulated in the regulations for the application of the law as that of the dental technician does. The modification of the medical services, the medical expences, waiting time, the easy access to the clinic of farmers, fishermen, urban laborers, and handicapped people, and the development of the area of the physical therapy.

• YAKHAK HOEJI
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• v.55 no.3
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• pp.213-218
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• 2011

The aim of this study is to evaluate the sedative effects of ethanol extract and the three major constituents of Cimicifugae Rhizoma. They decreased locomotor activity significantly, and enhanced sleeping duration induced by thiopental sodium. The ethanol extract of Cimicifugae rhizoma and 24-epi-7,8-didehydrocimigenol-3-xyloside (24-epi.) increased the $Cl^-$ influx into the intracellular area of SH-SY5Y neuroblastoma cells significantly. The present results demonstrate that the sedative effects of Cimicifugae rhizoma are mediated via the GABA-gated $Cl^-$ channel, partly by 24-epi.

• Corrosion Science and Technology
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• v.6 no.1
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• pp.18-23
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• 2007

DLC coatings have been deposited onto substrate of STS 316L and Ti alloy using r.f. PACVD (plasma-assisted chemical vapor deposition) with a mixture of $C_{6}H_{6}$ and $SiH_{4}$ as the process gases. Corrosion performance of DLC coatings was investigated by electrochemical techniques (potentiodynamic polarization test and electrochemical impedance spectroscopy) and surface analysis (scanning electron microscopy). The electrolyte used in this test was a 0.89% NaCl solution of pH 7.4 at temperature $37^{\circ}C$. The porosity and protective efficiency of DLC coatings were obtained using potentiodynamic polarization test. Moreover, the delamination area and volume fraction of water uptake of DLC coatings as a function of immersion time were calculated using electrochemical impedance spectroscopy. This study provides the reliable and quantitative data for assessment of the effect of substrate on corrosion performance of Si-DLC coatings. The results showed that Si-DLC coating on Ti alloy could improve corrosion resistance more than that on STS 316L in the simulated body fluid environment. This could be attributed to the formation of a dense and low-porosity coating, which impedes the penetration of water and ions.