• Proceedings of the KIEE Conference
• /
• 1999.07c
• /
• pp.1167-1169
• /
• 1999

This paper presents the new unified power flow controller(UPFC) load flow algorithm using UPFC transmission line constant model. The UPFC transmission line constant model represents a function of transmission line constant(G.B) UPFC's effect in power system. It can easily be incorporated in a load flow program. The algorithm is suited for monitoring the power system state as well as determining the magnitude and Phase angle of UPFC serial voltage source.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2008.04a
• /
• pp.413-415
• /
• 2008

In this paper, the new algorithm which eliminates structural noise and extracts the impact signature from the measured vibration signal is developed. We studied how the transient vibration signal due to the impact is distorted while propagating through the structure. Also the characteristics of noise generated by flow and the mechanical components are analyzed. The developed method is verified in the model plenum and the flow system in the laboratory. Results show the significant improvement in the sensitivity and accuracy.

• 한국지구물리탐사학회:학술대회논문집
• /
• 2003.11a
• /
• pp.432-436
• /
• 2003

Geophysical well logging techniques which are useful for delineating permeability of geological formation have been reviewed. A new technique for obtaining permeability using conductivity log technique has been discussed. This conductivity logging technique has been tested by monitoring the conductivity change within the model hole using borehole environment water and incoming-outgoing water of different salinity with constant flow rate by maintaining balance between inflow and outflow. Conductivity variation features depended mainly on flow rate, density contrasts due to salinity and temperature contrasts between fluid within the hole and incoming-outgoing fluid. The results of the experiment show uniform change of fluid conductivity within bore hole with time, and a fairly good correlation between the flow rate and the conductivity change rate. This conductivity logging technique is expected to be an efficient tool for determining permeability.

• KCID journal
• /
• v.13 no.2
• /
• pp.274-282
• /
• 2006

The objective of this study was to develop a hydrologic simulation model to predict daily streamflow from a small agricultural watershed considering irrigation return flow. The proposed IREFLOW(Irrigation REturn FLOW) model consists of hillslope runoff model, irrigation scheme drainage model, and irrigation return flow model, and simulates daily streamflow from an irrigated watershed. Two small watersheds were selected for monitoring of hydrological components and evaluating the model application. The relative error (RE) between observed and simulated daily streamflow were 2.9% and 6.4%, respectively, on two small agricultural watersheds (Baran and Gicheon) for the calibration period. The values of RE in daliy streamflow for the validation period were 6.0% for the Baran watershed, and 2.8% for the Gicheon watershed.

• Proceedings of the Korean Society of Fisheries Technology Conference
• /
• 2003.05a
• /
• pp.369-369
• /
• 2003

Hemocytes in marine bivalves play important immunological roles in discrimination, opsonization and phagocytosis of foreign materials as a defense mechanism. In this study we report the flow cytometric implications to investigate the immune parameters such as the compositional and the functional characteristics of hemocytes isolated from the Manila clams, Ruditapes philippinarum. Heterogeneity of the hemocytic cell population was determined by the forward scatter (FSC) and side scatter (SSC) cytometric profile which showed three populations: granulocytes, hyalinocytes and small agranular cells. In addition, phagocytosis rate was measured after adding fluorescent-labeled particles. The data were initially analysed for two-parameters: FSC and SSC, then the fluorescent (FL 1) frequency distribution histogram of the hemocyte population was subsequently obtained.

• Journal of Korean Society of Rural Planning
• /
• v.7 no.2 s.14
• /
• pp.13-25
• /
• 2001

Runoff and water quality was monitored from a watershed with small-scale livestock production farms. To evaluate pollution potential, land use, population, the size of livestock production of each farm, and livestock management method were surveyed. Climate and stream flow data were measured. Water samples were taken periodically for base flow conditions and some storm events. Pollutant loading was estimated by flow volume and concentrations of constituents. Delivery ratio of pollutant load was determined using estimated pollutant load.

• 한국방재학회:학술대회논문집
• /
• 2008.02a
• /
• pp.707-710
• /
• 2008

Recently, a rivers' bridge that locate on among the mountains area is destroyed by debris accumulation and debris flow, because of frequent occurrence of typhoon and a localized torrential downpour. therefore a river make a part of dam's effect. Actually, this situation gives damages like inundation of a bridge upper stream area's. Generally, It the main cause of the occurrence route of the debris accumulation is that outbreaks of driftwood and debris flow because of landslide, that occurred by severe rain storm. Also, a lot of debris are occurred when big flood come up during long period at this time, this kind of debris accumulation remove to other place, in several, and specially, debris accumlation move to the place where the depth of water is deep and velocity is fast river center. According to these kind of fact, this research put in effect and analyze that movement characteristic's numerical simulations of debris accumulation at flood according to a domestic outside literature investigation, on-site monitoring survey and parameter scenario which comes out through the hydraulic modeling analysis.

• Journal of Biosystems Engineering
• /
• v.30 no.5 s.112
• /
• pp.312-317
• /
• 2005

A flow injection type biosensor was tested to confirm the performance of a batch and a continuous type flow injection unit. Reproducibility and consistence of the biosensor were investigated to determine the effect of pulsations and air bubbles, and the applicability of on-line monitoring. The air bubbles affected the performance of the sensor irrespective of the location, and also the pulsations of the pump influenced the performance of the sensor. The applicability of on-line motoring was accepted as the result of the repeated and long-term measurements.

• 제어로봇시스템학회:학술대회논문집
• /
• 2001.10a
• /
• pp.86.5-86
• /
• 2001

This work describes a design and implementation of the level & flow rate control system by using a single-chip microcontroller. The proposed model system is designed based on the use of the single-chip microcontroller 8031 with the EPROM emulator for programming the computer software. The microcontroller reaches the input level and flow signals from the level sensor and the turbine flowmeter, respectively, via the signal conditioning circuits and A/D converters in order to calculate the control signal. Moreover, the status of the process variable can easily be set up and controlled by program monitoring through the emulator, and can be graphically displayed on the computer screen. Experiment results were carried out which can be ...

• Smart Media Journal
• /
• v.4 no.4
• /
• pp.24-32
• /
• 2015

Recently, SDN is actively used as datacenter networks and gradually increase its applied areas. Along with this change of networking environment, research of deploying network security systems on SDN becomes highlighted. Especially, systems for detecting network flooding attacks by monitoring every packets through ports of OpenFlow switches have been proposed. However, because of the centralized management of a SDN controller which manage multiple switches, it may be substantial overhead that the attack detection system continuously monitors all the flows. In this paper, a sampling based network flooding attack detection and prevention system is proposed to reduce the overhead of monitoring packets and to achieve reasonable functionality of attack detection and prevention. The proposed system periodically takes sample packets of network flows with the given sampling conditions, analyzes the sampled packets to detect network flooding attacks, and block the attack flows actively by managing the flow entries in OpenFlow switches. As network traffic sampler, sFlow agent is used, and snort, an opensource IDS, is used to detect network flooding attack from the sampled packets. For active prevention of the detected attacks, an OpenDaylight application is developed and applied. The proposed system is evaluated on the local testbed composed with multiple OVSes (Open Virtual Switch), and the performance and overhead of the proposed system under various sampling condition is analyzed.