• Clean Technology
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• v.5 no.2
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• pp.53-61
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• 1999

Presented is the design method of the waste heat recovery facility for the flue gas produced from combustion and incineration processes of large industrial environmental waste treatment and cogeneration plants. The present study assumes the basic design concept of wast heat recovery facility as the combination of waste heat recovery boiler and steam power cycle, and then describes the modeling technique, the design concept and criteria of each component of waste heat recovery facility. In addition, the present study investigates how the thermal performance of waste heat recovery facility varies with boiler operating pressure and waste heat recovery heat exchanger design at the same flue gas condition.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.1
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• pp.358-377
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• 2015

In this paper, we propose a novel approach for trajectory recovery. Our system uses a triangulation procedure for skeletonization and graph theory to extract the trajectory. Skeletonization extracts the polyline skeleton according to the polygonal contours of the handwritten characters, and as a result, the junction becomes clear and the characters that are touching each other are separated. The approach for the trajectory recovery is based on graph theory to find the optimal path in the graph that has the best representation of the trajectory. An undirected graph model consisting of one or more strokes is constructed from a polyline skeleton. By using the polyline skeleton, our approach accelerates the process to search for an optimal path. In order to evaluate the performance, we built our own dataset, which includes testing and ground-truth. The dataset consist of thousands of handwritten characters and word images, which are extracted from five handwritten documents. To show the relative advantage of our skeletonization method, we first compare the results against those from Zhang-Suen, a state-of-the-art skeletonization method. For the trajectory recovery, we conduct a comparison using the Root Means Square Error (RMSE) and Dynamic Time Warping (DTW) in order to measure the error between the ground truth and the real output. The comparison reveals that our approach has better performance for both the skeletonization stage and the trajectory recovery stage. Moreover, the processing time comparison proves that our system is faster than the existing systems.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.5
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• pp.58-66
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• 2011

A 2-loop waste heat recovery system with Rankine steam cycles for the improvement of fuel efficiency of gasoline vehicles has been investigated. A high temperature loop(HT loop) is a system to recover the waste heat from the exhaust gas, a low temperature loop(LT loop) is for heat recovery from the engine coolant cold relatively. This paper has dealt with a layout of a LT loop system, the review of the working fluids, and the design of the cycle. The design point and the target heat recovery of the LT boiler, a core part of a LT loop, has been presented and analytically investigated. Considering the characteristics of the cycle, the basic concept of the LT boiler has been determined as a shell-and tube type counterflow heat exchanger, the performance characteristics for various design parameters were investigated.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.54 no.8
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• pp.401-409
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• 2005

This paper describes a feasibility analysis result of STATCOM application for the Jeju-Haenam HVDC system. The Jeju-Haenam HVDC system is one of the typical HVDC system interconnected with the low short-circuit-ratio AC system, which is vulnerable to the commutation failure due to the AC voltage variation. STATCOM has been considered as an effective reactive-power compensator to increase short-circuit-ratio of the interconnected AC system. In this study, a simulation model of Jeju-Hacnam HVDC system with STATCOM was developed using PSCAD/EMTDC. The developed simulation model was utilized to analyze the dynamic performance analysis of Jeju-Haenam HVDC system with STATCOM. The analysis results show that STATCOM can improve the dynamic performance of Jeju-Haenam HVDC system, such as load-change recovery performance and fault recovery performance.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.60-62
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• 2005

This paper describes a feasibility analysis result of STATCOM application for the Jeiu-Haenam HVDC system. The Jeju-Haenam HVDC system is one of the typical HVDC system interconnected with the low short-circuit-ratio AC system, which is vulnerable to the commutation failure due to the AC voltage variation. STATCOM has been considered as an effective reactive-power compensator to increase short-circuit-ratio of the interconnected AC system. In this study, a simulation model of Jeju-Haenam HVDC system with STATCOM was developed using PSCAD/EMTDC. The developed simulation model was utilized to analyze the dynamic performance analysis of Jeju-Haenam HVDC system with STATCOM. The analysis results show that STATCOM can improve the dynamic performance of Jeju-Haenam HVDC system, such as load-change recovery performance and fault recovery performance.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.10
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• pp.1296-1309
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• 1999

A three dimensional compressible Navier-Stokes code is developed to analyze flowfields and performance of a vaned diffuser in a centrifugal compressor. It employs scalar implicit approximate factorization, finite volume formulation, second order upwind differencing and a two-equation $q-{\omega}$ turbulence model based on the integration to the wall. Pressure recovery and loss coefficients of a vaned diffuser are evaluated using a developed computer code. The simulated three dimensional flows show how through flow structure affects pressure recovery performance and loss coefficients of a vane for design and off-design inlet flow angles. Development of complex three dimensional flow over the inlet region and leading edge are very influential to the overall flow and performance.

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.872-877
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• 2001

This study analyzed the design performance of the bottoming system of combined cycle power plants adopting a single-pressure once-through heat recovery steam generator with reheat. A computer program was constructed and parametric analyses were carried out to present the criteria for determining the reheat pressure and the location of the starring point of the reheater in the HRSG. The performance of the bottoming system was presented for the range from high subcritical to supercritical pressures. It was founded that the power of the bottoming system can be as high as that of the present triple-pressure bottoming system even with a higher exhaust gas temperature. A requirement for this high performance is a proper arrangement of the reheater.

• Journal of Electrical Engineering and Technology
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• v.13 no.2
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• pp.881-885
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• 2018

In order to develop a gas circuit breaker (GCB), the breaking performance of the short line fault (SLF) should be prioritized over that of the breaker terminal fault (BTF). In brief, it is necessary to evaluate the thermal characteristics of the insulating gas that is filled in a GCB. In the process of developing a GCB, many companies use the simplified synthetic testing facility (SSTF).In order to evaluate the SLF breaking performance of a GCB with a long minimum arcing time, a modifications to the conventional SSTF was proposed. In this study, we developed the SSTF with a modified transient recovery voltage circuit. The performance of the newly developed SSTF was verified by an $L_{90}$ breaking performance test on a rating combination of 170 kV, 50 kA, and 60 Hz.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.6
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• pp.628-630
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• 2016

Compressive sensing can recover an original sparse signal from a few measurements. Its performance is affected by the number of non-zero elements in the signal. The knowledge of partial locations of non-zero elements can improve the recovery performance. In this paper, we apply the partial location knowledge to the multipath matching pursuit. The numerical results show it improves the signal recovery performance and the channel estimation performance in the ITU-VB channel.

• Preventive Nutrition and Food Science
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• v.4 no.3
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• pp.167-170
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• 1999

Various concentrations of malonaldehyde (MA) produced upon hydrolysis of 1, 1, 3,3-tetraethoxypropane (TEP) were reacted with 2-thiobarbituric acid (TBA)and th e contents of MA-TBA complex were measured both with spectrophotometer and high performance liquid chromatography (HPLC). As the concentrations of MA-TBA increased, their absorbances and the corresponding HPLC peak areas increased. The correlation coefficient between absorbances and HPLC peak areas of MA-TBA peaks from the other compounds and butanol extraction of the complex increased its recovery its recovery by 29.4% . Measurement of the content of MA-TBA complex for monitoring the development of lipid oxidation was proven to be successful with the use of high performance liquid chromatography.