• 조명전기설비학회논문지
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• 제29권10호
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• pp.39-46
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• 2015

REMICON(Ready Mixed Concrete), the most essential material of construction work, is produced from facility called "Batcher plant." In order to produce Remicon, Batcher Plant needs to be supplied with basic raw material such as ballast, sand, cement, admixture and water. In remicon industry, overland transport vehicles are used during the whole manufacturing process from producing to infilling at the construction site. Thus, the transportation cost sums up be to 20 percent of whole manufacturing cost and transport capacity and distance travelled have direct and major effect on manufacturing costs. This paper suggests a method to find optimal location of batcher plant using modified Steiner point, suggesting the most effective and flexible connection through among construction site, aggregate, cement and remicon producing plant. This paper also proposes reducing of transport cost at maximum 60% by calculation through optimized plant location. The modified Steiner point theory proposed in this paper also can be applied to optimal location of a $2^{ry}$ substation or MCC panel for minimizing of power loss, voltage drop, line distance and etc.

• Journal of Biosystems Engineering
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• 제29권2호
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• pp.121-130
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• 2004

This study was carried out to develop a miller to produce white embryo rice with functional nutrients by improving the conventional vertical miller. The effects of rice moisture content and the shaft revolution speed of the miller on germ(embryo) adherence rate, whiteness, broken rice rate, and cracked rice rate were investigated. Also, the effect of the mesh size of emery stones on the germ adherence rate was investigated. The vertical prototype miller was improved with the increasement of about 42% in producing white embryo rice at proper conditions(shaft revolution speed of 900 rpm, emery stones of mesh ＃50, processing capacity of 2.3t/h, zero outlet resistance, rice moisture content of 16.2%). The results were as follows: 1. The germ adherence rate of white rice was significantly influenced by the moisture content of brown rice. The germ adherence rate of white rice decreased rapidly with the increase of the moisture content of brown rice. When brown rice with moisture content of 13.2%, 14.5%, 15.2%, 15.4% was milled by the prototype with emery stones of mesh ＃35 and shaft speed of 900(1,100) rpm, rpm adherence rate of milled rice was 76.2%(70%), 69.2%(66%), 45.9(38%), 13.0(9%), respectively. 2. The whiteness of white rice milled by the prototype with emery stones of mesh ＃35 and shaft speed of 1,100(900)rpm increased from 27(23) to about 40, respectively, as the moisture content of brown rice increased from 13.2% to 17.2%. 3. The rate of broken rice of white rice milled at 900rpm decreased by 0.6∼1.0% compared with that at 1,100rpm when the moisture content of brown rice was less than 15.2%. 4. The germ adherence rate was increased by 10.3% and 11.0%, respectively when brown rice with moisture content of 16.2% and 15.5% was milled by the prototype miller with shaft speed of 900rpm and emery stones of mesh ＃50 instead of mesh ＃35. 5. Considering the germ adherence rate, broken rice rate, and whiteness of milled rice, the proper milling conditions of the prototype miller for producing embryo rice were the moisture content of about 15%, the processing capacity of 2.3t/h and minimum outlet resistance of 0Nㆍm with shaft speed of 900rpm and emery stones of mesh ＃50.

• 미생물학회지
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• 제45권4호
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• pp.339-345
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• 2009

김치로부터 오르니틴을 생산하는 능력이 있는 2개의 젖산균주(OK1-4, OK1-6)를 분리하여 그 특성을 조사하였다. 분리된 균주는 그람 양성, 단간균이었으며, 혐기적 조건에서 이산화탄소를 생성하였다. MRS 배지에서 $25\sim37^{\circ}C$ 범위와 pH 6.0~7.0 범위에서 잘 자랐으며, 성장을 위한 최적 온도와 pH는 각각 $30^{\circ}C$와 pH 6.5이었다. 분리된 젖산균주는 L-아라비노스, 자일로스, 리보오스, 글루코오스 등의 당을 분해하여 산을 생성하였고, cellobiose, galactose, raffinose, trehalsoe는 분해하지 못하였다. 16S rDNA 염기서열분석을 통해 분리된 균주는 유전자은행에 등재되어 있는 Weissella koreensis S5623(AY035891)의 염기서열과 각각 99.6%와 99.7%의 서열 동질성이 있음을 확인하였다. 이와같은 생화학적 특성과 염기서열 분석결과를 토대로 분리된 균주를 Weissella koreensis OK1-4와 Weissella koreensis OK1-6로 각각 명명하였다. 이들 균주의 오르니틴 생성능력은 1% 아르기닌이 첨가된 MRS 배지에서 각각 27.01와 31.41 mg/L/h 이었다. 이와같은 결과는 우리김치로부터 분리된 Weissella 속 균주의 오르니틴 생성에 관한 최초의 보고이다.

• 디지털융복합연구
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• 제14권7호
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• pp.363-371
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• 2016

벤처기업의 기술혁신을 위한 기술력 평가는 급변하는 기업환경, 평가시 사용하는 언어의 모호성과 애매성, 평가지표의 부정확성을 고려해야 한다. 본 논문에서는 벤처기업의 대표적인 정성적 평가요인인 흡수역량 및 기술적 기업가정신을 대상으로 다기준 의사결정법인 Fuzzy-AHP를 적용하여 요인의 중요도와 우선순위 및 동적역량을 산출하는 ACTEM(Absorption Capacity and Technology Entrepreneurship Monitor) 모델을 제안하였다. 평가척도가 되는 요인에 대한 가중치 산출은 퍼지이론을 도입하여 인지적 판단의 애매성을 보완하고, 기존의 기술력 평가 측정에 관한 연구에서 고려하지 않은 흡수역량과 기술적 기업가정신 및 동적역량에 대한 평가 기준들을 제시함으로써, 현실적인 대안을 선택하는 것이 가능하도록 하였다. ACTEM 모델을 기존의 AHP 평가방법과 비교한 결과, 흡수역량에서는 '지식획득', 기술적 기업가 정신에서는 '제품화 능력'이 가장 높게 나오는 등의 타당성을 검증할 수 있었다.

• Nuclear Engineering and Technology
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• 제41권8호
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• pp.1005-1014
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• 2009

The Dual Unit Optimizer 2000 MWe (DUO2000) is put forward as a new design concept for large power nuclear plants to cope with economic and safety challenges facing the $21^{st}$ century green and sustainable energy industry. DUO2000 is home to two nuclear steam supply systems (NSSSs) of the Optimized Power Reactor 1000 MWe (OPR1000)-like pressurized water reactor (PWR) in single containment so as to double the capacity of the plant. The idea behind DUO may as well be extended to combining any number of NSSSs of PWRs or pressurized heavy water reactors (PHWRs), or even boiling water reactors (BWRs). Once proven in water reactors, the technology may even be expanded to gas cooled, liquid metal cooled, and molten salt cooled reactors. With its in-vessel retention external reactor vessel cooling (IVR-ERVC) as severe accident management strategy, DUO can not only put the single most querulous PWR safety issue to an end, but also pave the way to very promising large power capacity while dispensing with the huge redesigning cost for Generation III+ nuclear systems. Five prototypes are presented for the DUO2000, and their respective advantages and drawbacks are considered. The strengths include, but are not necessarily limited to, reducing the cost of construction by decreasing the number of containment buildings from two to one, minimizing the cost of NSSS and control systems by sharing between the dual units, and lessening the maintenance cost by uniting the NSSS, just to name the few. The latent threats are discussed as well.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제8권3호
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• pp.170-174
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• 2008

The measurement of performance of a process considering both the location and the dispersion of information about the process is referred to as the process capacity indices (PCIs) of interest, $C_{pk}$. This information is presented by the mean and standard deviation of the producing process. Linguistic variables are used to express the evaluation of the quality of a product. Consequently, $C_{pk}$ is defined with fuzzy numbers. Lee [Eur. J. Oper. Res. 129(2001) 683-688] constructed the definition of the $C_{pk}$ index estimation presented by fuzzy numbers and approximated its membership function using the "min" - norm based Zadeh's extension principle of fuzzy sets. However, Lee's result was shown to be invalid by Hong [Eur. J. Oper. Res. 158(2004) 529-532]. It is well known that $T_w$ (the weakest t-norm)-based addition and multiplication preserve the shape of L-R fuzzy numbers. In this paper, we allow that the fuzzy numbers are of L-R type. The object of the present study is to propose a new method to calculate the $C_{pk}$ index under $T_w-based$ fuzzy arithmetic operations.

• 대한안전경영과학회지
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• 제18권4호
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• pp.99-105
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• 2016

This study was conducted to develop a dummy in an environment similar to the human body, to prepare a standard for evaluation and to present the process of the production in order to evaluate the performance of the robot that can detect the persons needing rescue in a confined space, who are difficult for fire-fighting officials to rescue in case of fire and disaster. As a result, a standard for evaluation was developed and standardized into four parts 'Normal,' 'Risk Stage 1,' 'Risk Stage 2' and 'Risk Stage 3'based on the number of breath cycles, carbon dioxide concentration, core temperature and criteria for hearing to recognize the voice. In addition, in order to produce a dummy, fever, breathing capacity and voice output function were compared and analyzed. This study has significance that it built up basic data of the method of producing the actual dummy, by presenting characteristics and controlling methods using the waterproof insulation heating coil for the function, solenoid valve for the consecutive output of breathing capacity and USB program sound board for voice output.

• 대한의용생체공학회:의공학회지
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• 제41권6호
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• pp.264-271
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• 2020

The purpose of this study was to investigate the effects of active vibration exercise of upper limb on physical capacity index (endurance, grip strength, balance, and flexibility) and vasomotor index (capillary length and body surface temperature) in middle aged women. 20 participants randomly divided into two groups: vibro-swing exercise (VSE) and non vibro-swing exercise (NVSE). Subjects in each group measured the 30 second arm curl test, hand dynamometer, one leg standing test, back scratch test, nail fold capillary microscope (NFM), and digital infrared thermal imaging (DITI) before and after exercise. The results showed that active vibration exercise of upper limb with vibro-swing equipment increased the endurance, balance ability, and the capillary length. In addition, changes in body temperature immediately after exercise were predicted to affect vasomotor. Active vibration exercise of upper limb has the advantage of being able to exercise anywhere regardless of the location by inducing different frequency changes in movement of various ranges and velocity. For this reason, the combination of vibration and active movement can be expected the physiological effects when producing exercise programs for middle aged women.

• 신재생에너지
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• 제18권1호
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• pp.35-45
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• 2022

The renewable energy based MG is becoming one of the prominent solutions for greenhouse gas and constructing less power lines. However, how to procure the economics of MG considering the CO₂ emission and utility network impact is one of major issues as the proportion of renewable resource increases. This paper proposes the feasibility study scheme of campus MG and shows that the LCOE and CO₂ emission can be reduced by utilizing the excess power and introducing hydrogen system and plus DR. For this, the three cases: (a) adding the PV and selling excess power to utility, (b) producing and selling hydrogen using excess power, and (c) participating in plus DR are considered. For each case, not only the topology and component capacity of MG to secure economic feasibility, but also CO₂ emission and utility network effects are derived. If an electrolyzer with a capacity of 400 kW participates in plus DR for 3,730hours/year, the economic feasibility is securable if plus DR settlement and hydrogen sale price are more than 7.08¢/kWh and 8.3USD/kg or 6.25¢/kWh and 8.6USD/kg, respectively. For this end, continuous technical development and policy support for hydrogen system and plus DR are required.

• 한국구조물진단유지관리공학회 논문집
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• 제21권2호
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• pp.69-77
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• 2017

공장생산으로 신속한 시공이 가능한 모듈러 시스템은 하중저항 방식에 따라 보-기둥 프레임식의 개방형 모듈러 시스템과 패널 및 스터드로 이뤄진 폐쇄형 모듈러 시스템으로 구분할 수 있다. 그 중 개방형 모듈러 시스템은 폐쇄형 단면형상으로 모듈간 접합이 어려우며, 특정부분의 하중 집중현상으로 국부좌굴이 발생하여 내력이 저감될 가능성이 있다. 본 연구에서는 기존 모듈러 시스템의 문제점을 해결하기 위하여 절곡형 단면 안에 콘크리트를 채운 합성단면을 사용한 모듈러 시스템을 제안하였다. 제안된 시스템의 내진 성능 평가를 위해 ATC 40의 능력스펙트럼 해석법을 사용하였으며, 일반적인 모듈러시스템의 결과와 비교하여 성능을 검증하였다. 해석결과에 따르면 성능점에서 합성단면을 사용한 모듈러시스템의 소성힌지 갯수 및 변형량이 적게 나타났다. 이를 토대로 제안된 합성단면의 내진성능이 기존 부재 보다 우수 것으로 판단하였다.