• The Journal of Fisheries Business Administration
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• v.28 no.2
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• pp.39-66
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• 1997

The objective of this study is to suggest the improvement method of the profitability in our marine fish culture business. So I investigated the actual condition for aquaculture farms in South Sea coast by the question and actual survey. 1 recognized the following facts; 1) The marine floating netcage system are a great portion in two province - Kyeongnam and Cheunnam, 2) The rockfish are reared absolutely much more than the olive flounder, 3) The polyculture by various species are more carried out than the monoculture of the olive flounder or rockfish, etc. I analyzed the profitability in olive flounder monoculture, rockfish monoculture, olive flounder and rockfish polyculture, and rockfish polyculture taking turns year by year respectively. At a result I comfirmed that the net income to net sales was the highest in the olive flounder monoculture bacouse the olive flounder,s sale price was higher than rockfish price. But internal rate of return(IRR) and net present value(NPV) were high in the olive flounder and rockfish polyculture or the rockfish taking turns polyculture. The reasons were alttributed to their high utility of a netcage and to reduction of a capital cost. So, I suggest 1) to feed the bigger product in short term, 2) to reduction of a feed and seed cost, 3) to increase a survival rate of fish and 4) to enlarge production by highly utilizing a netcage. And I recognized that a aquaculture manager should make constantly an effort to gain more profit by rearing more good products and by reducing a production cost.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.04a
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• pp.409-416
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• 2004

An active modal-fuzzy control method using hydraulic actuators is presented for seismic response reduction. In the proposed control system, a new fuzzy controller designed in the modal space produces the desired active control force. This type controller has all advantages of the fuzzy control algorithm and modal approach. Since it is very difficult to select input variables used in fuzzy controller among an amount of state variables in the active fuzzy control system the presented algorithm adopts the modal control algorithm which is able to consider more easily information of all state variables in civil structures that are usually dominated by first few modes. In other words, all information of the whole structure can be considered in the control algorithm evaluated to reduce seismic responses and it can be efficient for especially civil structures. In addition, the presented algorithm is expected to magnify utility and performance caused by efficiency that the fuzzy algorithm can handle complex model more easily. An active modal-fuzzy control scheme is applied together with a Kalman filter and a low-pass filter to be applicable to real civil structures. A Kalman filter is considered to estimate modal states and a low-pass filter was used to eliminate spillover problem. The results of the numerical simulations far a wide amplitude range o f loading conditions and for historic earthquakes having various frequency components show that the proposed active modal-fuzzy control system can be beneficial in reducing seismic responses of civil structures.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2005.03a
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• pp.513-520
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• 2005

An active modal-fuzzy control method using hydraulic actuators is presented for seismic response reduction. In the proposed control system, a new fuzzy controller designed in the modal space produces the desired active control force. This type controller has all advantages of the fuzzy control algorithm and modal approach. Since it is very difficult to select input variables used in fuzzy controller among an amount of state variables in the active fuzzy control system, the presented algorithm adopts the modal control algorithm which is able to consider more easily information of all state variables in civil structures that are usually dominated by first few modes. In other words, all information of the whole structure can be considered in the control algorithm evaluated to reduce seismic responses and it can be efficient for especially civil structures. In addition, the presented algorithm is expected to magnify utility and performance caused by efficiency that the fuzzy algorithm can handle complex model more easily. An active modal-fuzzy control scheme is applied together with a Kalman filter and a low-pass filter to be applicable to real civil structures. A Kalman filter is considered to estimate modal states and a low-pass filter was used to eliminate spillover problem. The results of the numerical simulations for a wide amplitude range of loading conditions show that the proposed active modal-fuzzy control system can be beneficial in reducing seismic responses of civil structures.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.11a
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• pp.157-160
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• 2009

The decision of the Form removal time which leads the early assuring strength of the concrete from Apartment construction is the fact which is important from Reducing the period of works and the economical efficiency side. Especially, with Complex building of recent times the same Tall building and Multiple Apartment Site which only follows in upgrade of interior construction of apartment site and shortening the frame construction period becomes very, importantly is the actual condition where the effort which is various for this is attempted. But is caused by with limit and economical efficiency problem of case concrete early strength revelation of most and is not put to practical use is the actual condition. Develops concrete mixture which is a utility from the research which sees hereupon and the effect which is economic leads construction duration shortening under maximizing boil.

• Journal of Energy Engineering
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• v.26 no.1
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• pp.45-53
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• 2017

The best practices of energy efficiency were selected by reviewing cases collected from the results of IEA research and prior studies, and then by evaluating the correspondence of each case for four attributes including economic performance, synergy, political adjustment, and marketability. The selected best practices included 36 cases in 6 fields such as governance, finance, utility, home, transportation, and industry/small and medium-sized businesses. The reduction of energy costs has brought countries implementing best practices of energy efficiency a variety of benefits, including higher rate of return, the reduction of incidental expenses, the increase of productivity, and the improvement of accessibility to energy. To have similar effects, other countries need to adjust these best practices before applying to their situations.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.4
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• pp.13-18
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• 1999

Recently among after-treatment devices which have high possibility of utility diesel oxidation catalyst(DOC) is concerned over the world. DOC oxidizes pollutants by means of activate-reaction during by-passing in the catalyst in doing so conversion efficiency of PM, CO and HC is high and this device does not have an effect on engine performance because back pressure is not nearly increased, But as a small amount of sulfur content in fuel is oxidized it makes sulfate which is absorbed on the surface of catalyst. So in this study the experiment is carried out by means of using ordinary fuel(0.1wt%) and low sulfur fuel(0.05wt%) with DOC and the emission gas of diesel engine is measured.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.377-382
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• 2004

This paper presents a novel optimization method for the air- and gas-supplying network comprised of several air compression systems and air and gas streams in an industrial chemical plant. The optimization is based on the hybrid model developed by Han and $Han^1$ for predicting the power consumption of a compression system. A constrained optimization problem was formulated to minimize the total electric power consumption of all the compression systems in the air- and gas-supplying network under various operating constraints and was solved using a successive quadratic optimization algorithm. The optimization approach was applied to an industrial terephthalic acid manufacturing plant to achieve about 10% reduction in the total electric power consumption under varying ambient conditions.

• The Transactions of the Korean Institute of Power Electronics
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• v.4 no.5
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• pp.413-422
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• 1999

Auto-connected multipulse(12/24pulse) rectifier schemes are cost effective methods for reducing line current hamonics in PWM drive systems. Employing these schemes to enhance utility power quality requires careful attention to several design considerations In particular, excursion of dc-link voltage at no load, effect of pre-existing voltage distortion, impedance mismatches, unequal diode drops on rectifier current sharing and performance, are fully analyzed, Several corrective measures to improve the performance of 12/24­pulse rectifier systems are also discussed. Finally, experimental results on a 460V, 60Hz 400kVA commercial ASD, retrofitted with 12/24pulse rectifier systems are discussed in detail.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.541-543
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• 2004

An optimal soot blowing system has been developed for an optimal operation of power utility boilers by both minimization of the use of steam and the number of soot blowers worked during soot blowing. Traditionally, the soot blowing system has been operated manually by operators. However, it causes the reduction of power and thermal performance degradation because all soot blowers installed in the plant should be worked simultaneously even there are lots of tubes those are not contaminated by slagging or fouling. Heat transfer area is divided into four groups, furnace, convection area including superheater, reheater and economizer, and air preheater in the present study. The condition of cleanness of the tubes is calculated by several parameters obtained by sensors. Then, a part of soot blowers works automatically where boiler tubes are contaminated. This system has been applied in a practical power plant. Therefore, comparison has been done between this system and manual operation and the results are discussed.

• Journal of radiological science and technology
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• v.17 no.2
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• pp.13-20
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• 1994

The paper is on the record of radiography the patients with SIEMENS ANGIOSTAR/POLYTRON S PLUS angiosystem with DSA system in the Chonbuk National University Hospital from October 1993 to June 1994. The results are as follow : 1. Among the total No, 836 case of utilization, angiography are 316(37.8 %), interventional radiography are 256(34.2 %), and dacryocystography and sialography are 168(20/1 %). Therefore non-angiogrlphy procedure are incerasing. 2. The aomunt of contrast material used are half as much as conventional angiovascular system. 3. The amount of film consumed are $10{\sim}15%$ of that of conventional angio vascular system and reduction of procedure time are $40{\sim}50%$. 4. Admitting that dignostic utility is in the utilization by examination region, there should be technological study which deal with fine vessel and motion artifact problem.