• Journal of Korean Society of Transportation
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• v.14 no.1
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• pp.117-133
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• 1996

In the paper a superior performance algorithm compared to the existing vehicle actuated controller and time fixed controller and the additional controller is described through realization of fuzzy traffic phase controller. Fuzzy theory is encouraging since the application is similar to human's decision ability that is approately coped with uncertain conditions. The paper presents that selection of the phase adequated the variable traffic conditions through the fuzzy theory algorithm and decision of optimal cycle time approated the uncertain traffic volume are predominant in traffic jam solution compared to the existing Webster's cycle time decision method and the sequential traffic phase design method and dual-ring phase operation system.

• Journal of Chest Surgery
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• v.23 no.2
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• pp.333-341
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• 1990

aortoiliac pattern, Group II; femoropopliteal pattern and Group g; tibioperoneal pattern. A majority of patients belonged to group I [27 cases], 8 patients came under group II .and none in group g. Thirty patients underwent bypass operation with autogenous saphenous vein or synthetic graft with or without concomitant lumbar sympathectomy. Remaining 5 patients were operated on with sympathectomy only, Bypass procedures were anatomic bypass in 22 cases: aortoiliac artery bypass in 11 cases, femoropopliteal artery bypass in 10 cases, sequential femoropopliteal artery bypass in one case and extra-anatomic bypass in 8 cases, axillary-bifemoral artery bypass in one case and femorofemoral artery bypass in 7 cases. Postoperative complications which mainly composed of superficial wound infection[5 cases] which were treated without any significant sequel in all cases and thrombosis[2 cases]. Three patients died whose causes of death were acute renal failure in 2 cases and myocardial infarction in other, The overall patency, rate was 70Zo in 5 years. In conclusion, the clinical pattern and operative outcome were similar to he western pattern and all cases of death did not related to operative procedures and ischemic symptoms were relieved by bypass operations except several cases. I think and recommend that all patients suffering chronic arterial insufficiency by atherosclerosis obliterans ought to be managed with urgent and adequate operative procedure.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.6
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• pp.1046-1052
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• 2010

In residential house, photovoltaic (PV) system among various alternatives in renewable energy system is the most efficient and feasible solution for reducing energy consumption and electricity cost. However, relatively high initial cost make people reluctant to install PV system in their houses. Therefore, in the initial state for PV system installation in the house, it is very important to decide proper capacity of the PV system considering the expected energy usage and solar energy supplying condition with the house. This paper proposes a novel optimization model for deciding appropriate capacity of the PV system for residential house. The objective function of the model is to minimize the annual cost including electricity bill, operation and maintenance cost, and annual fixed cost calculated from the initial installation cost based on capital recovery factor (CRF). The model also shows the optimal inclining angle of PV panels of the system. In this paper, we estimate the PV output using PVWATTS (PV simulator of Office of Energy Efficiency and Renewable Energy) and find optimal solutions by Sequential Quadratic Programming (SQP) method using MATLAB software. The proposed approach is finally applied to a residential model house in Gangneung, Gangwon-Do and verified its feasibility for adopting to PV system design for residential houses.

• Journal of Korea Multimedia Society
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• v.8 no.1
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• pp.1-8
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• 2005

Similar melody searching is an operation that finds such melodies similar to a given query melody from a music database. In this paper, we address the development of a system that detects plagiarism based on the similar melody searching. We first Propose a novel similarity model that supports alignment as well as shifting. Also, we suggest a method for indexing the features extracted from each melody, and a method for processing plagiarism detection by using the index. By our plagiarism detection system composers can easily searches for such melodies that are similar to their ones from music databases. Through performance evaluation via a series of experiments, we show the effectiveness of our approach. The results reveal that our approach outperforms the sequential-scan-based one in speed up to around 31 times.

• Journal of the Korean Society of Combustion
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• v.15 no.3
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• pp.48-56
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• 2010

Performances of power generation engine were investigated with syngas from RPF. A stoker type, multi-staged pyrolysis-gasification system, was employed for syngas generation and the syngas was refined with the sequential cleaning processes composed of a gas cooler, a bag filter and a wet scrubber. 20 kWe commercial syngas power generation engine was adopted to burn the cleaned syngas which is mainly composed of hydrogen, carbon monoxide, carbon dioxide and methane. The performance of the engine was tested with various syngas compositions and the results were compared to LNG case. Electric power output, exhaust gas temperature, and emission characteristics were measured, and the efficiency of engine generation was investigated as a function of load of power generation.

• Nuclear Engineering and Technology
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• v.52 no.7
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• pp.1587-1596
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• 2020

The location selection for nuclear power plants (NPP) is a strategic decision, which has significant impact operation of the plant and sustainable development of the region. Further, the ranking of the alternative locations and selection of the most suitable and efficient locations for NPPs is an important multi-criteria decision-making problem. In this paper, the non-sequential Monte Carlo probabilistic method and the Latin hypercube sampling probabilistic method are used to evaluate and select the optimal locations for NPP. These locations are identified by the power plant's onsite loads and the average of the lowest number of relay protection after the NPP's trip, based on electricity considerations. The results obtained from the proposed method indicate that in selecting the optimal location for an NPP after a power plant trip with the purpose of internal onsite loads of the power plant and the average of the lowest number of relay protection power system, on the IEEE RTS 24-bus system network given. This paper provides an effective and systematic study of the decision-making process for evaluating and selecting optimal locations for an NPP.

• The KIPS Transactions:PartA
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• v.9A no.2
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• pp.225-230
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• 2002

The constrained off-line competitive deletion problem is a simple form of the set manipulation operations problem. It excludes the insertion operation from the off-line competitive deletion problem. An optimal sequential algorithm and a CREW PRAM algorithm which runs $O(log^2nloglogn)$ time using O(n/loglogn) processors were already presented in the literature. In this paper, we present a reconfigurable mesh algorithm for the constrained off-line competitive deletion problem. The proposed algorithm is executed in a constant time on an $n{\times}n$ reconfigurable mesh, and the result is $AT^2$ optimal.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1603-1605
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• 2001

Eight 300kJ modularized capacitor-banks have been constructed. These modules have been installed and assembled to make a 2.4MJ pulse power system (PPS). This 2.4MJ PPS was developed to be used as a driver of an electrothermal-chemical (ETC) gun. Each capacitor bank has six 22kV, 50kJ capacitors connected in parallel. A triggered vacuum switch (TVS-43) was adopted as a main pulse power-closing switch in each module. The module also contains a crowbar circuit made of three high-voltage diode-stacks, a multi-tap inductor and an energy-dumping resistor. Various current shapes have been formed by a sequential firing of multiple capacitor banks. Resistive dummy load has been used and various combinations of experimental parameters, such as charging voltage, trigger time and inductance, were tested to make flexible current shapes.

• Journal of Hydrogen and New Energy
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• v.15 no.3
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• pp.187-193
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• 2004

In this study, Anaerobic sewage sludge in a batch reactor operation at $35^\circ{C}$ was used as the seed to investigate the effect of pretreatments of waste activated sludge and to evaluate its hydrogen production potential by anaerobic fermentation. Various pretreatments including physical, chemical and biological means were conducted to utilize for substrate. As a result, SCODcr of alkali and mechanical treatment was 15 and 12 times enhanced, compared with a supernatant of activated sludge. And SCODcr was 2 time increase after re-treatment with biological hydrolysis. Those were shown that sequential hybridized treatment of sludge by chemical & biological methods to conform hydrogen production potential in bath experiments. When buffer solution was added to the activated sludge, hydrogen production potential increased as compare with no addition. Combination of alkali and mechanical treatment was higher in hydrogen production potential than other treatments.

• Wind and Structures
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• v.24 no.4
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• pp.385-403
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• 2017

In recent years, the wind energy has played an increasingly important role in national energy sector of many countries. To harvest more electric power, the wind turbine (WT) tower structure becomes physically larger, which may cause more risks during long-term operation. Associated with the great development of WT projects, the number of accidents related to large-scaled WT has also been increased. Therefore, a structural health monitoring (SHM) system for WT structures is needed to ensure their safety and serviceability during operational time. The objective of this study is to develop a hybrid damage detection method for WT tower structures by measuring vibration and impedance responses. To achieve the objective, the following approaches are implemented. Firstly, a hybrid damage detection scheme which combines vibration-based and impedance-based methods is proposed as a sequential process in three stages. Secondly, a series of vibration and impedance tests are conducted on a lab-scaled model of the WT structure in which a set of bolt-loosening cases is simulated for the segmental joints. Finally, the feasibility of the proposed hybrid damage detection method is experimentally evaluated via its performance during the damage detection process in the tested model.