• KSCE Journal of Civil and Environmental Engineering Research
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• 제14권5호
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• pp.1055-1067
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• 1994

This paper is presented to perform linear dynamic analysis of bridges due to vehicle moving on bridges. The road surface roughness and bridge/vehicle interaction are also considered. The bridge and vehicle are modeled as 3-D bridge and vehicle model, respectively. The road surface roughness of the roadway and bridge decks are generated from power spectral density(PSD) function for good road. The PSD function proposed by C.J. Dodds and J.D. Robson is used to describe the road surface roughness for good road condition. The vehicles are modeled as two nonlinear vehicle model with 7-D.O.F of truck and 12-D.O.F of tractor-trailer and the equations of motion of the vehicles are derived using Lagrange's equation. The main girder and concrete deck are modeled as beam and shell element, respectively and rigid link is used between main girder and concrete deck. The equations of motion of the vehicles are solved by Newmark ${\beta}$ method and the equations of the motion of the bridges are solved by mode-superposition procedures. The validity of the proposed procedure is demonstrated by comparing the results with the experimental data reported by the AASHO Road Test. The comparison shows that the agreement between experiment and theory is quite satisfactory.

• Journal of Society of Preventive Korean Medicine
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• 제7권1호
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• pp.123-132
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• 2003

It is considered to be important to create aesthetically beautiful style through the change of external shape, however for the hair stylists, whose beauty expression is through hair, the role of hair doctor is becoming even more important with focus to improve the hair healthiness. Hair clinic is management of hair and scalp. It is the management process of preventing damages, while improving and cultivating healthy and shiny hair. The current concept in hair management is moving from simple hair styling to emphasis at hair management. As far as hair management is concerned, it usually includes treatment tools such as shampoo, conditioner, hair treatment and scalp scaling system, which is used for diagnosis of hair condition in order to treat the scalp. As the interest of hair healthiness becoming more wide spread, so does the breadth of clinic menu. The wide choice is to fulfill the profound desire of people, whose demands are simply to have variety in their choice. This is resulting in faucets of new value-added and differentiated products. The values that make-up the hair styles consist of mainly design (trend, preference), function(styling, management convenience) and clinic(hair quality improvement, damage repair). Shampoo and conditioner have gone beyond their original function of cleansing to providing combinational functions of treatment, to care and remedy, and advanced massage effectiveness. These are, to name a few that seem to go beyond their original function to satisfy the mental healthiness in people, the King Kong shampoo of shampooings in forward-backward manner, 5-minute shampoo massage that applies sports and relaxation massage, scalp acupunctural message and aural(ear) massage. More and more people are complaining about the damaged hair and hair loss problems due to perms, dyeing and bleaching of hair, in addition to natural scalp and hair damaging factors. Such complaints have stimulated many beauty products and various hair treatment systems being introduced with focus to provide nutrition and prevent damages to scalp and hair. As the living standards improve and the desire of people is to pursue differentiated lives, their demand also increases in hair styling products to fulfill the needs of healthy and aesthetical aspects of their lives.

• Wind and Structures
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• 제20권4호
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• pp.549-564
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• 2015

The three-dimensional unsteady incompressible Reynolds-averaged Navier-Stokes equations and k-${\varepsilon}$ double equations turbulent model were used to investigate the effect on the measurements of anemometers due to a passing high-speed train. Sliding mesh technology in Fluent was utilized to treat the moving boundary problem. The high-speed train considered in this paper was with bogies and inter-carriage gaps. Combined with the results of the wind tunnel test in a published paper, the accuracy of the present numerical method was validated to be used for further study. In addition, the difference of slipstream between three-car and eight-car grouping models was analyzed, and a series of numerical simulations were carried out to study the influences of the anemometer heights, the train speeds, the crosswind speeds and the directions of the induced slipstream on the measurements of the anemometers. The results show that the influence factors of the train-induced slipstream are the passing head car and tail car. Using the three-car grouping model to analyze the train-induced flow is reasonable. The maxima of horizontal slipstream velocity tend to reduce as the height of the anemometer increases. With the train speed increasing, the relationship between $V_{train}$ and $V_{induced\;slipstream}$ can be expressed with linear increment. In the absence of natural wind conditions, from the head car arriving to the tail car leaving, the induced wind direction changes about $330^{\circ}$, while under the crosswind condition the wind direction fluctuates around $-90^{\circ}$. With the crosswind speed increasing, the peaks of $V_X,{\mid}V_{XY}-V_{wind}{\mid}$ of the head car and that of $V_X$ of the tail car tend to enlarge. Thus, when anemometers are installed along high-speed railways, it is important to study the effect on the measurements of anemometers due to the train-induced slipstream.

• Journal of Fisheries and Marine Sciences Education
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• 제29권1호
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• pp.201-208
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• 2017

The major cause of the marine accidents is the collision with a moving object such as ship as well as the fixed object such as breakwater. Therefore, the most effective way to reduce the maritime ship accidents is the prevention of collision. In order to decrease the collision, it is principle that the navigation officer promptly judges the dangerous condition and makes the quick response. The ship does not allow any object or other ships approaching its surrounded area called ship area so that it prevents the collision. Generally, the ship which has high speed or poor maneuvering capability shall be managed from the distance so that the other ship does not invade its ship domains(watching distance, blocking distance). Accordingly, this study sets the navigational risk assessment model by applying ship dynamic domain and collision judgement method considered ship length, speed and navigational capability. It also reviewed the validity of the model and evaluated the perilous water way (Maenggol Channel) and a curved route near Maenggol Channel. As a result, in case of a ship with 100m in length passing Maenggol Channel, it represented "warning" level before 1.5nm to the entry, "dangerous"level 0.75nm before to it and "very dangerous" level 0.5nm before to it and then "dangerous"level again up to the entry. Applying to the curved route also showed the same results as the Narrow Channel or Maenggol Channel. This analysis highly matched with the actual navigation results. In the future, this model will be useful for coastal navigation safety chart development and safety evaluation for route or port development. It also allows to evaluate the dangerous route or the best route by applying the result into ECDIS so that it will finally help to reduce the marine accidents. Eventually the model will be effective for the marine traffic simulation evaluation forced by Maritime Traffic Safety Act.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2006년도 공동학술대회 논문집
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• pp.141-151
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• 2006

A blank test was done to calculatee the car itself's magnetic effect as noise and to eliminate it from the data set of total magnetic intensity(=magnetic flux density) exploration in a car-borne magnetic exploration system. To calculate the induced magnetic intensity(= magnetization) and the remanent magnetic intensity(= magnetization) of the car itself, we have installed the magnetometer on a fixed point and measured the magnetic intensity letting the car move around the magnetometer, and we have changed the data set into an analogous data set as if acquired in the condition that we have parked the car on the same fixed point and measured the magnetic intensity moving the magnetometer around the magnetometer. Through an inversion with the later data set as input, we have calculated the magnetic center and the magnetic moments of the induced magnetic intensity(= magnetization) and the remanent magnetic intensity(= magnetization) of the car itself with the two centers coincided because of some barriers of the inversion algorithm that we have used in this study. On the other hand, we have extracted the magnetic anomaly by reducing i. e. vectorially eliminating the induced magnetic intensity(= magnetization) and the remanent magnetic intensity(= magnetization) of the car itself calculated forwardly, from the magnetic exploration data set acquired by the car-borne magnetic exploration system.

• Journal of Korean Society of Water and Wastewater
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• 제21권6호
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• pp.727-735
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• 2007

The use of water by cities is increasing owing to industrialization, the concentration of population, and the enhancement of the standard of living. Accordingly, the amount of waste water is also increasing, and the degree of pollution of the water system is rising. In order to solve this problem, it is necessary to remove organisms and suspended particles as well as the products of eutrophication such as nitrates and phosphates. This study developed a high-end treatment engineering solution with maximum efficiency and lower costs by researching and developing a advanced treatment engineering solution with the use of Biosorption. As a result, the study conducted a test with a $50m^3/day$ Pilot Scale Plant by developing treatment engineering so that only the secondary treatment satisfies the standard of water quality and which provided optimal treatment efficiency along with convenient maintenance and management. The removal of organisms, which has to be pursued first for realizing nitrification during the test period, was made in such a way that there would be no oxidation by microorganisms in the reactor while preparing oxygen as an inhibitor for the growth of microorganism in the course of moving toward the primary settling pond. The study introduced microorganisms in the endogeneous respiration stage to perform adhesion, absorption, and filtering by bringing them into contact with the inflowing water with the use of a sludge returning from the secondary settling pond. Also a test was conducted to determine how effective the microorganisms are as an inner source of carbon. The HRT(Hydraulic Retention Time) in the nitrification tank (aerobic tank) could be reduced to two hours or below, and the stable treatment efficiency of the process using the organisms absorbed in the NAR reactor as a source of carbon could be proven. Also, given that the anaerobic condition of the pre-treatment tank becomes basic in the area of phosphate discharge, it was found that there was excellent efficiency for the removal of phosphate when the pre-treatment tank induced the discharge of phosphate and the polishing reactor induced the uptake of phosphate. The removal efficiency was shown to be about 94.4% for $BOD_5$. 90.7% for $COD_{Cr}$ 84.3% for $COD_{Mn}$, 96.0% for SS, 77.3% for TN, and 96.0% for TP.

• KSCE Journal of Civil and Environmental Engineering Research
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• 제36권3호
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• pp.573-586
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• 2016

In construction jobs, a combination of various kinds of machinery is used to perform earthworks at a large-scale site. Individual equipments essentially cooperate with each other on task such as excavation, load, transfer and compaction. While other area have studied cooperation system, related study in domestic construction is in poor condition. In this study, construction equipment fleet management system is developed for solving this problem and find way to improving efficiency in earthworks site. The entire concept of the fleet management system, including its components and process, has been systematically outlined in this paper. An operational methodology has also been suggested, where a number of machines, such as the excavators, trucks and compactors, are chosen and further grouped into a cluster. A case study verify fleet management system's effectiveness on performing task package by comparing existing work method with methodology in this study. Fleet management system in this study is expected to curtail fuel consumption by the reduction of working time and moving distance. Furthermore, it can be anticipated to declining carbon emission effect.

• Atmosphere
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• 제19권2호
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• pp.183-198
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• 2009

The purpose of this study is to summarize the tropical cyclone (TC) activity of 2008 over the western North Pacific including the verification of the official track and intensity forecast errors of these TCs. The TC activity - frequency, Normalized Typhoon Activity (NTA), and life span - was lower than 58-year (1951-2008) average. 22 tropical cyclones of tropical storm (TS) intensity or higher formed in the western North Pacific and the South China Sea in 2008. The total number is less than 58-year average frequency of 26.4. Out of 22 tropical cyclones, 11 TCs reached typhoon (TY) intensity, while the rest 11 TCs only reached severe tropical storm (STS) and tropical storm (TS) intensity - six STS and five TS storms. One typhoon KALMAEGI (0807) among them affected the Korea peninsula. However, no significant impact - casualty or property damage - was reported. On average of 22 TCs in 2008, the Korea Meteorological Administration (KMA) official track forecast error for 48 hours was 229 km. There was a big challenge for individual cyclones such as 0806 FENGSHEN and 0817 HIGOS presenting significant forecast error, with both intricate tracks and irregular moving speed. The tropical cyclone season in 2008 began in April with the formation of NEOGURI (0801). In May, four TCs formed in the western North Pacific in response to enhanced convective activity. On the other hand, the TC activity was very weak from June to August. It is found that the unusual anti-cyclonic circulation in the lower level and weak convection near the Philippines are dominant during summertime. The convection and atmospheric circulation in the western North Pacific contributed unfavorable condition for TC activity in the 2008 summertime. The 2008 TC activity has continued the below normal state since mid 1990s which is apparent the decadal variability in TC activity.

• Journal of Korea Multimedia Society
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• 제7권11호
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• pp.1597-1609
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• 2004

A lot of lipreading system has been proposed to compensate the rate of speech recognition dropped in a noisy environment. Previous lipreading systems work on some specific conditions such as artificial lighting and predefined background color. In this paper, we propose a real-time lipreading system which allows the motion of a speaker and relaxes the restriction on the condition for color and lighting. The proposed system extracts face and lip region from input video sequence captured with a common PC camera and essential visual information in real-time. It recognizes utterance words by using the visual information in real-time. It uses the hue histogram model to extract face and lip region. It uses mean shift algorithm to track the face of a moving speaker. It uses PCA(Principal Component Analysis) to extract the visual information for learning and testing. Also, it uses HMM(Hidden Markov Model) as a recognition algorithm. The experimental results show that our system could get the recognition rate of 90% in case of speaker dependent lipreading and increase the rate of speech recognition up to 40～85% according to the noise level when it is combined with audio speech recognition.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제31권4C호
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• pp.341-350
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• 2006

The sand table training is one of the most effective training method in military operations which can accomplish missions such as simulation and rehearsal without limitations related to time, space, money and so on. Previous sand table training has many problems like that the sand table cannot represent real field condition because of its physical properties. So, it is hard to be preserved and impossible to include much of information into them. In this paper, we make an approach based on Augmented Reality(AR) to solve these problems and propose an efficient military training briefing tool with virtual sand table environment described as actual battle field Virtual Tactical Map(VTM) can realize a virtual military training with simple action like moving marker or tangible interface by hand. Real-time state information of VTM gives us more organic intelligence for entire situation. Tangible AR interface provides users with a contents authoring tool that is natural, intuitive and easy to deal with as interaction between user in real world and system that augmented real world with virtual object. VTM is a newly designed military training briefing tools. A military training content can be reproduced and it is possible that user uses this content later. Thus, it shows us potential possibilities of AR applications on military leaning field.