• Journal of Wetlands Research
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• v.13 no.2
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• pp.363-375
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• 2011

Recently, Water quiality of urban river largely have gotten better by virtue of sewer pipe laying and sewage treatment plants construction. or the various contaminants which is flowed in into river have generated underwater ecosystem disturbance and red tide by lack of sewage and waste water disposal facilities. With tidal river, taehwa river of ulsan metropolitan city has large river width and gradual stream bed gradient at the dry and storage period. Moreover, the flow is paralyzed due to the bridge pier protection work, consist of the mat foundation which is about 1.2km from two bridge and the contaminant is accumulated. it is caused by of the red tide generated from the several years or it activates. In this study, When flow area is largest by changing independent footing of bridge pier of two bridges and using RMA2 model, we hydraulically analyzed a variable breadth of velocity and discharge. Consequently, flow rate increased the maximum 103%, discharge was exposed to increase the maximum 61%. Directly this cannot extinguish the red tide but suppresses the red tide occurrence or can reduce. And it is determined to prevent the depositioning of the contaminant and can control fundamentally the red tide occurrence cause.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.2
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• pp.75-84
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• 2018

The purpose of this study is that the low-cost mobile mapping system using INS (Inertial Navigation System) based on MEMS (Micro Electro Mechanical System) could decipher the interpretation of road facility with the accuracy of x, y 0.546m plane error. Even though the MMS (Mobile Mapping System) technology as a new measurement technology has been used vividly to set up geographic information by some world leading surveying equipment manufacturers, the domestic technology is still in its beginning stage. Several domestic institutes and companies tried to catch up the leading technology but they just produced prototypes which needs more stabilization. Through this thesis, we developed low-cost mobile mapping system installed with INS based on MEMS after time synchronizing sensors for MMS such as LiDAR (Light Detection And Ranging), CCD (Charge Coupled Device), GPS/INS (Global Positioning System / Inertial Navigation System) and DMI (Distance Measurement Instrument).

• Journal of Korea Society of Industrial Information Systems
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• v.22 no.4
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• pp.11-18
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• 2017

The Objective of this Study is to Prove the Effectiveness of a Smart Water Management(SWM) Technology. The SWM Technology can Reduce the Production Cost using Internet of Thing(IoT) Technology that Utilizes Remote Metering of Consumer's Water usage and Reduce the Leakage of Supply Facilities. The SWM Demonstration Model Installed a Remote Water Leakage Sensor, Smart Metering and Micro Multi Sensor in Water Supply Facility, and Provided Real-Time Monitoring of the Operation Status. Consumers can be Provided the usage of Tap Water and the Water Puality through a Smart Phone Application. At this Time, we Surveyed Whether Consumers save the Tap Water or Drinking Directly using the Tap Water usage Information. Also, this Study is to Verify the Degree of Improvement of Water Supply Rates and Drinking Water Rate, and to Decrease Consumer's Complaints, Operating Costs, and Water Consumption by the SWM Technology. It is also Established a SWM Model Combined with the IoT Sensor at Supply Facilities, operator monitoring system and explored recovery solution detected events. It means the upbringing of the domestic water industry by developing the related technologies and spreading the SWM to advanced levels.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.254-254
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• 2010

Cu-Pc(copper(II)-phthalocyanine)는 박막의 형성과정에서 열처리 방식과 온도에 따라 박막의 구조가 변하며, 구조로는 열적으로 준 안정적인 $\alpha$-phase와 열적으로 안정적인 $\beta$-phase가 있다. 본 연구에서는 Cu-Pc 박막의 열적으로 안정적인 $\beta$-phase 구조에 대해 온도 조건 변화에 따른 표면 결정 성장의 특성을 연구하고자 한다. 진공증착 방법 중 하나인 thermal evaporation deposition을 이용하여 glass 기판위에 전열 처리 및 후열 처리에 대해 온도 조건 변화에 따른 $\beta$-phase type의 표면 결정 특성을 연구하였다. Cu-Pc 박막의 성장두께는 50nm 일정한 두께로 fluxmeter 및 thickness monitor를 이용하여 제어하였다. 50nm의 두께에 따른 기판온도를 $100^{\circ}C$, $200^{\circ}C$, $300^{\circ}C$로 전열 처리한 후 각각 전열 처리한 기판온도에 대해 1hour, 2hour, 3hour 후열 처리하여 온도 조건에 따른 박막을 성장한 후, $\beta$-phase type에 대한 결정 구조 및 표면 특성 변화를 분석하였다. 제작된 Cu-Pc의 박막은 $\beta$-phase type으로, 열처리에 따른 $\beta$-phase transition 현상을 연구하였다. XRD(X-ray diffraction)를 통하여 박막에 대한 결정 구조 분석 및 FE-SEM(field emission scanning electron microscopy)을 이용하여 Cu-Pc 박막의 구조적 결정성과 방향성 등, 표면 상태와 형상구조에 대해 표면의 특성을 분석하며, 광 흡수도(UV-visible absorption spectra)을 이용하여 온도 조건에 따른 투과/흡수 현상을 비교분석하였다.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.2
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• pp.277-284
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• 2023

It is not easy to implement an energy management system in an industrial complex where small businesses are scattered, so the method of collecting and adjusting energy-related data is mainly used. FEMS is a system that responds to the demand for a paradigm shift from a passive energy management method to an active energy management method using IoT and ICT. In this study, a factory energy management system(FEMS) is designed for small and medium-sized enterprises located in chemical industrial complexes. Efficiency was confirmed by reviewing energy saving measures and efficiencies through FEMS for the electric energy of facilities built in each company. The cost effectiveness of FEMS is created when it is utilized by responsible and empowered personnel within the business processes of the host company. Therefore, it is necessary to utilize EMS that can be applied to the planning, support, operation and evaluation, and continuous improvement of the energy management system to achieve corporate organization and energy management goals.

• Journal of Korea Water Resources Association
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• v.51 no.1
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• pp.35-48
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• 2018

Groynes are installed generally to protect the riverside or the river bank from the erosion caused by water flows by controlling the flow direction and velocity in rivers. In the past, groynes were used to secure enough depth of water in canals. As there has been a growing interest in river restoration and the natural river maintenance since 2000, groynes are proposed as a major environmental hydraulic structure because the flow control and various river bed conditions around the groyne can contribute to habitat functions. Groynes are typically installed in a series. In designing groyne series, groyne spacing is an important factor because the flow changes in the main canal and the flow inside the groyne area occurs variably depending on the groyne spacing. This study provide information to determine the groyne spacing suitable for the purpose of the groyne by examining the flows that variably changes according to the groyne spacing and angle in the recirculation zone of the groyne field. In particular, the formation of vortex, the location of vortex core and the water flow near the river bank, all of which occur in the recirculation zone inside the groyne area, were mainly analyzed to examine the flow characteristics near the river bank that influences the safety of the river bank area. The results of the experiment will serve as important basic data to examine changes in the river bed inside the groyne area as well as the safety of river banks following the installation of groyne series.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.6
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• pp.286-304
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• 2017

In this study, we proposed a new-type of circular perforated caisson breakwater consisting of a bundle of latticed blocks that can be applied to a small port such as a fishing port, and numerically investigated the hydraulic characteristics of the breakwater. The numerical method used in this study is OLAFOAM which newly added wave generation module, porous media analysis module and reflected wave control module based on OpenFOAM that is open source CFD software published under the GPL license. To investigate the applicability of OLAFOAM, the variations of wave pressure acting on the three-dimensional slit caisson were compared to the previous experimental results under the regular wave conditions, and then the performance for irregular waves was examined from the reproducibility of the target irregular waves and frequency spectrum analysis. As a result, a series of numerical simulations for the new-type of circular perforated caisson breakwaters, which is similar to slit caisson breakwater, was carried out under the irregular wave actions. The hydraulic characteristics of the breakwater such as wave overtopping, reflection, and wave pressure distribution were carefully investigated respect to the significant wave height and period, the wave chamber width, and the interconnectivity between them. The numerical results revealed that the wave pressure acting on the new-type of circular perforated caisson breakwaters was considerably smaller than the result of the impermeable vertical wall computed by the Goda equation. Also, the reflection of the new-type caisson breakwater was similar to the variation range of the reflection coefficient of the existing slit caisson breakwater.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.9
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• pp.765-774
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• 2009

Fiber Dyeing and Finishing facility has been recognized as an important pollution source due to its consumption of large volumes of water and chemicals. Unit mass discharge for the conventional water quality parameters such as flowrate, SS, $BOD_5,\;COD_{Mn},\;COD_{Cr}$, TN, TP were estimated. To represent the respective industries, three companies were carefully selected based on its manufacturing goods, flowrate and location at various unit operations and processes. More than 90% of decrease in unit mass estimation between influent and effluent of BOD was observed. But the values themselves were similar to those of Fiber Manufacturing facility due to the high loadings of organic matter. Biodegradability of influent was almost three times higher than that of effluent. Unit mass discharge estimations of unit process (estimated in this study) based on space, products and raw material were similar to those of composite process (estimated by National Institute of Environmental Research), while big difference was observed in the other factors. Unit mass discharge factors calculated in this study can be used as the reference for the estimation of water pollution loading costs in Nakdong river basin. For the effective water pollution control and management, it is essential to characterize the various types of water quality parameters from the effluents of individual industrial wastewater treatment plants.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.22 no.6
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• pp.374-386
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• 2010

Recently, the theoretical and experimental research is being made actively in control character of waves of perforated-wall caisson breakwater like the slit caisson. This study showed that the character of reflection coefficient and the wave pressure acting on the front and inner of slit caisson were estimated in two and three dimensional numerical wave flume and compared each other. The numerical experiment was set and conducted by various cases as to a variety of wave steepness under 7 sec, 9 sec, 11sec and 13 sec period condition. In this study using a 2 and 3 dimensional numerical wave flume, it applied the Model for the immiscible two-phase flow based on the Naveir-Stokes Equations. This technique can easily reproduce a complicated physical phenomenon more than others and organize the program simply. According to the results of the experiment, the reflection coefficient was estimated high in short-period waves. However, 2-dimensional numerical experiment and 3-dimensional numerical experiment were the same in case of the long-period waves and high wave steepness. And to conclude in case of short-period waves the pressures were a relatively small difference between the two, but there was a big gap in longperiod waves and high wave steepness.

• Journal of the Korean Geotechnical Society
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• v.24 no.2
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• pp.67-75
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• 2008

It is interesting to note that distinct element method has been used extensively to model the response of micro and discontinuous behavior in geomechanics. Impressive advances related to response of distinct particles have been conducted and there were difficulties in considering fluid effect simultaneously. Current distinct element methods are progressively developed to solve particle-fluid coupling focused on fluid flow through soil, rock or porous medium. In this research, numerical simulations of fluid injection into particulate materials were conducted to observe cavity initiation and propagation using distinct element method. After generation of initial particles and wall elements, confining stress was applied by servo-control method. The fluid scheme solves the continuity and Navior-Stokes equations numerically, then derives pressure and velocity vectors for fixed grid by considering the existence of particles within the fluid cell. Fluid was injected as 7-step into the assembly in the x-direction from the inlet located at the center of the left boundary under confining stress condition, $0.1MP{\alpha}\;and\;0.5MP{\alpha}$, respectively. For each simulation, movement of particles, flow rate, fluid velocity, pressure history, wall stress including cavity initiation and propagation by interaction of flulid-paricles were analyzed.