• Journal of Radiation Industry
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• v.2 no.3
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• pp.155-161
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• 2008

A hydraulic scale model was constructed to investigate the characteristics of flows and pollutant transport in laboratory. The distorted hydraulic scale model by assuming Froude similarity was adopted to represent hydrodynamics and dispersion in a river system. The scale model was composed of water reservoir, slope control part, booster pump, distributing plate and main channel. A constructed scale model will be used to present the overall concentration profiles of tracer and a research will be performed to convert the measured values using a hydraulic scale model to real field scale.

• Nuclear Engineering and Technology
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• v.34 no.4
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• pp.301-313
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• 2002

This paper proposes a quantitative approach to modeling the information processing of NPP operators. The aim of this work is to derive the amount of the information processed during a certain control task. The focus will be on i) developing a model for information processing of NPP operators and ii) quantifying the model. To resolve the problems of the previous approaches based on the information theory, i.e. the problems of single channel approaches, we primarily develop the information processing model having multiple stages, which contains information flows. Then the uncertainty of the information is quantified using the Conant’s model, 3 kind of information theory.

• Journal of the Korean Institute of Rural Architecture
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• v.26 no.2
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• pp.73-84
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• 2024

This study investigated the outpatient departments of Infectious Disease Hospitals by Region, which play an important role in establishing regional medical networking, to find a spatial structure that can provide a safe environment for efficient diagnosis and treatment, as well as a rational medical procedure in case of crisis. Department layout and adjacencies were derived by considering the access procedures according to patient classification, medical procedures by department, and connectivity with other departments. Based on the results derived by setting up zones according to infection control, activities, and objects, and analyzing the division of zones, the composition of areas by activities, movement flows by objects and treatment units, it can be used as basic data for the architectural plan of the Infectious Disease Hospital. Also, there are implications that can be used as basic data for planning related facilities by analyzing spatial relationships according to user behavior.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.4
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• pp.391-396
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• 2009

In this paper, a control algorithm for DC-Link voltage unbalancing compensation of a four-switch inverter for a three-phase BLDC motor drive is proposed. Compared with a conventional six-switch inverter, the split source of the four-switch inverter can be obtained by splitting DC-link capacitor into two capacitors to drive the three phase BLDC motor. The voltages across each of two capacitors are not always equal in steady state because of the unbalance in the impedance of the DC-link capacitors $C_1$ and $C_2$ or the variable current flowed into the capacitor's neutral point in motor control. Despite the unbalance, if the BLDC motor may be run for a long time the voltage across one of the capacitors is more increased. So the unbalance in the capacitors voltages will be accelerated. As a result, The current ripple and torque ripple is increased due to the fluctuation of input current which flows into 3-phase BLDC motor. According to that, the vibration of motor will be increased and the whole system will be instable. This paper presents a control algorithm for DC-Link voltage unbalancing compensation. The sampling from the voltages across each of two capacitors is used to perform the voltage control of DC-Link by using the feedforward controller.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.158-163
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• 2005

Competitive electricity markets necessitate equitable methods for allocating transmission usage in order to set transmission usage charges and congestion charges in an unbiased and an open-accessed basis. So in competitive markets it is usually necessary to trace the contribution of each participant to line usage, congestion charges and transmission losses, and then to calculate charges based on these contributions. A UPFC offers flexible power system control, and has the powerful advantage of providing, simultaneously and independently, real-time control of voltage, impedance and phase angle, which are the basic power system parameters on which sys-tem performance depends. Therefore, UPFC can be used efficiently and flexibly to optimize line utilization and increase system capability and to enhance transmission stability and dampen system oscillations. In this paper, a mathematical approach to allocate the contributions of system users and UPFCs to transmission system usage is presented. The paper uses a dc-based load flow modeling of UPFC-inserted transmission lines in which the injection model of the UPFC is used. The relationships presented in the paper showed modified distribution factors that modeled impact of utilizing UPFCs on line flows and system usage. The derived relationships show how bus voltage angles are attributed to each of changes in generation, injections of UPFC, and changes in admittance matrix caused by inserting UPFCs in lines. The relationships derived are applied to two test systems. The results illustrate how transmission usage would be affected when UPFC is utilized. The relationships derived can be adopted for the purpose of allocating usage and payments to users of transmission network and owners of UPFCs used in the network. The relationships can be modified or extended for other control devices.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.24 no.1
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• pp.48-57
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• 2012

In this study, 3-dimensional hydraulic model experiment and 3-dimensional numerical analysis were carried out to review the control performance on the solitary waves by attaching the resonator suggested in this study to the openings of the existing rectangular harbors and breakwaters placed in a straight line. In the numerical analysis, TWOPM-3D of 3-D one-field Model for immiscible TWO-Phase flows method using 3-dimensional numerical wave tank was applied, and the validity of the numerical analysis method was verified through comparative analysis between hydraulic experimental results and numerical analysis results. In addition, the effectiveness of the resonator was identified as a result of review on the control performance to control solitary waves of the resonance devices through comparison with cases where the resonators are attached or not.

• Journal of Environmental Impact Assessment
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• v.22 no.1
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• pp.27-37
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• 2013

The fish fauna and disturbance of geographical distributions in the eastern Civilian Control Line of Korea were investigated from May to September 2012. Total 35 species sampled during the period were belonged to 13 families. There were 9 Korean endemic species (25.71%) that distributed in the flows into West and South Sea. Distributions of invasion fishes in the studied streams based on geographical distributions of freshwater fish were total 13 species that classified 1 species, C. cuvieri from foreign country and 12 species from other water systems. Hence there have been anthropogenically introduced from too many years ago. Also groups according to the similarities of each studied stations was divided into 4 groups by similarity 50% because difference in them was considered to effect of domestic invasion species. In conclusion, three streams in the eastern Civilian Control Line of Korea were invaded by many alien fishes. Therefore, we are considered to require precise investigation and monitoring for the preparations to management measure.

• Child Health Nursing Research
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• v.8 no.4
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• pp.400-413
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• 2002

The purpose of this study was to evaluate the effect of informational intervention on postoperative pain following tonsillectomy in children. This study was performed on 30 children, aged 5-15 years, undergoing tonsillectomy and their parents by providing informational intervention with colored figure; operation procedure and information. Pain assessment was done by Pain Questionnaire. The results from this study were as follows : 1. Children in experimental group with mean 16.07 had lower pain scores than control group with mean 14.87 at 4th hours after operation(p<0.05). It showed 'significant difference' and first hypothesis was adopted. 2. Children in experimental group with mean 20.60 had lower pain scores than control group with mean 17.27 at 8th hours after operation(p<0.05). It showed 'significant difference' and second hypothesis was adopted. 3. Children in experimental group with mean 28.80 had lower pain scores than control group with mean 25.70 at 24th hours after operation(p<0.05). It showed 'significant difference' and third hypothesis was adopted. 4. When we analyzed the time difference and difference between two groups simultaneously by repeated measure ANOVA, the significant difference was not found. And so 'the experiential group with operation-related information will show the lower pain sense than the control group just as the time flows after operation', fourth hypothesis was rejected. Generally, it was found that providing information about operation to children and their parents reduced effectively postoperative pain in children, but in clinical settings there are minimum preoperative information-providing because of insufficient time and inconvenience although nursing staffs and patients know its needs. Conclusionally providing preoperative information should help children and their parents cope with Pre, Peri and Post operative events effectively.

• Journal of KIISE
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• v.42 no.1
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• pp.114-121
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• 2015

Large-scale wireless sensor networks are constructed by using a large number of sensor nodes that are non-uniformly deployed over a wide area. As a result, the data collected by the sensor nodes are similar to that from one another since a high density of the sensor nodes may cause an overlap. As a result of the characteristics of the traffic, data is collected from a plurality of sensor nodes by a sink node, and when the sensor nodes transmit their collected data to the sink node, the sensor nodes around the sink node have a higher amount of traffic than the sensor nodes far away from the sink node. Thus, the former sensor encounter bottlenecks due to traffic congestion and have an energy hole problem more often than the latter ones, increasing energy consumption. This paper proposes a congestion control scheme that considers traffic flows in order to control traffic congestion of the sensor nodes that are non-uniformly deployed over a large-scale wireless sensor network.

• Journal of Korean Society of Transportation
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• v.19 no.6
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• pp.143-160
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• 2001

Micro-simulation models have been recognized as an efficient assessment tool in developing traffic signal control technologies. In this paper a prototype of a microscopic simulation model which can be applied to evaluate the performance of traffic-adaptive signal control strategies was developed. In the simulation process, space-based arrays were appled to estimate parameters of car following and lane changing models. Two levels of link types, a micro-type and macro-type links, were also embodied in the simulation process. The proposed model was tested on a test network consists of 9 intersections. The performance of the proposed model was evaluated in link by link comparisons with the results of NETSIM. The results show that the proposed model could appropriately simulate traffic flows of the test network. The model also produces traffic adaptive signal timings, cycle lengths and green times for turning movements, based on the detector data. It implies that the optimization process of the model produces reasonable signal timings for the test network on the cycle basis.