• IE interfaces
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• v.8 no.3
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• pp.61-73
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• 1995

As the level of maunfacturing system automation increases, the issues of modeling and simulation of AMS(Automated Manufacturing System) are becoming more important. Proposed in this paper is the JR-Net(Job Resource relation-Net) modeling framework which naturally mimics the process of designing an AMS by FA(Factory Automation) engineers. Its main purpose is to provide a modeling tool which facilitate modeling work of AMS for FA engineers unfamiliar with simulation modeling. The proposed modeling scheme is based on the extensive observation that typical AMSs are built from the set of 'standard' components(or catalog items). As an application of the proposed model, two real examples of FMS('G7'FMS model plant, RPI FMS) are modeled by JR-Net, and in case of FMS model plant, a simulation program development procedure using JR-Net modeling results is explained. Finally, simulation result of FMS model plant is analyzed.

• Nuclear Engineering and Technology
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• v.39 no.3
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• pp.171-186
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• 2007

Critical issues in the development targets for the future fast reactor(FR) cycle system, including sodium-cooled FR were to ensure safety assurance, efficient utilization of resources, reduction of environmental burden, assurance of nuclear non-proliferation, and economic competitiveness. A promising design concept of sodium-cooled fast reactor JSFR is proposed aiming at fully satisfaction of the development targets for the next generation nuclear energy system. A roadmap toward JSFR commercialization is described, to be followed up in a new framework of the Fast reactor Cycle Technology development(FaCT) Project launched in 2006.

• Journal of Power System Engineering
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• v.18 no.6
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• pp.120-125
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• 2014

In this paper, suitable working fluid of 1MW Organic Rankine Cycle(ORC) with liquid-vapor ejector using effluent from power plant is selected. The results of comparison performance of 5 refrigerants are as follows; R600a, R134a, R1270, R236fa, R235fa. The operating parameters considered in this study include the condensation capacity evaporation capacity and efficiency. As a result of comparison of basic ORC system and with liquid-vapor ejector, with ORC system presents the higher system efficiency since the ejector makes the turbine outlet pressure lower than condensation pressure through its pressure recovery. Also, this ejector ORC system is advantageous in miniaturizing the size of components owing to decrease of evaporation capacity and condensation capacity.

• Journal of the Korea Society of Computer and Information
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• v.6 no.3
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• pp.78-83
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• 2001

In this paper, we are considered Nakagami-m fading, which can model variable multipath mobile radio communication channel, in DS-CDMA system. System modeling using nakagami -m fading is suited for urban mobile communication channel with multipath. We used adaptive serial search PN code acquisition scheme and derived the detection probability($P_D$) and false alarm probability($P_FA$) which have influence on code acquisition time, over Nakagami-m fading. Detection probability($P_D$) and false alarm probability($P_FA$) are detection variable to decide PN code acquisition time and should use to calculate mean and variance. of acquisition time. From computer simulation, we analyzed mean and variance about PN code acquisition of fading channel. Then we can apply it to the H/W design of mobile communication.

• Computers and Concrete
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• v.32 no.2
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• pp.119-138
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• 2023

Concrete carbonation is a prevalent phenomenon that leads to steel reinforcement corrosion in reinforced concrete (RC) structures, thereby decreasing their service life as well as durability. The process of carbonation results in a lower pH level of concrete, resulting in an acidic environment with a pH value below 12. This acidic environment initiates and accelerates the corrosion of steel reinforcement in concrete, rendering it more susceptible to damage and ultimately weakening the overall structural integrity of the RC system. Lower pH values might cause damage to the protective coating of steel, also known as the passive film, thus speeding up the process of corrosion. It is essential to estimate the carbonation factor to reduce the deterioration in concrete structures. A lot of work has gone into developing a carbonation model that is precise and efficient that takes both internal and external factors into account. This study presents an ML-based adaptive-neuro fuzzy inference system (ANFIS) approach to predict the carbonation depth of fly ash (FA)-based concrete structures. Cement content, FA, water-cement ratio, relative humidity, duration, and CO2 level have been used as input parameters to develop the ANFIS model. Six performance indices have been used for finding the accuracy of the developed model and two analytical models. The outcome of the ANFIS model has also been compared with the other models used in this study. The prediction results show that the ANFIS model outperforms analytical models with R-value, MAE, RMSE, and Nash-Sutcliffe efficiency index values of 0.9951, 0.7255 mm, 1.2346 mm, and 0.9957, respectively. Surface plots and sensitivity analysis have also been performed to identify the repercussion of individual features on the carbonation depth of FA-based concrete structures. The developed ANFIS-based model is simple, easy to use, and cost-effective with good accuracy as compared to existing models.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.6
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• pp.717-723
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• 2006

Chemical characteristics of soybean oil after deep-frying with potato sticks (200 g, 10% w/w of soybean oil) were studied according to the 34 deep-frying times. After consecutive 34 deep-frying, total polyunsaturated FA contents was gradually decreased while the total saturated FA and trans FA were increased. Acid value and peroxide value were increased while iodine value decreased, respectively. The Hunter $L^{\ast}$ value decreased while each $a^{\ast}\;and \;b^{\ast}b$ value were gradually increased. Electronic nose equipped with 12 metal oxide sensors was used for the discrimination of odor pattern of frying oils against the times of deep-trying. The proportions of 1st and 2nd principal component analysis showed 75.97% and 21.23%, respectively. While 6 among total 12 sensors well responded to discrimination of odor in the repented frying oils, suggesting that the odor pattern of each oil after deep-frying would be discriminated against fresh soybean oil, especially after 14 times. From the results, electronic nose could differentiate the degree of quality deterioration of the repeated deep-frying oils.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.1
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• pp.107-112
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• 2020

We analyze the flow aggregate (FA) based network delay guarantee framework, with generalized minimal interleaved regulator (IR) initially suggested by IEEE 802.1 time sensitive network (TSN) task group (TG). The framework has multiple networks with minimal IRs attached at their output ports for suppressing the burst cascades, with FAs within a network for alleviating the scheduling complexity. We analyze the framework with various topology and parameter sets with the conclusion that the FA-based framework with low complexity can yield better performance than the integrated services (IntServ) system with high complexity, especially with large network size and large FA size.

• The KSFM Journal of Fluid Machinery
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• v.16 no.3
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• pp.10-17
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• 2013

The organic Rankine cycle has been widely used to convert the renewable energy such as the solar energy, the geothermal energy, or the waste energy etc., to the electric power. Some previous studies focused to find what kind of refrigerant would be a best working fluid for the organic Rankine cycle. In this study, R245fa was chosen to the working fluid, and the cycle analysis was conducted for the output power of 30kW or less. In addition, properties (temperature, pressure, entropy, and enthalpy etc.) of the working fluid on the cycle were predicted when the turbine output power was controlled by adjusting the mass flowrate. The configuration of the turbine was a radial-type and the supersonic nozzles were applied as the stator. So, the turbine was operated in partial admission. The turbine efficiency and the optimum velocity ratio were considered in the cycle analysis for the low partial admission rate. The computed results show that the system efficiency is affected by the partial admission rate more than the temperature of the evaporator.

• Proceedings of the KSMRM Conference
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• 2003.10a
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• pp.20-20
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• 2003

Purpose： To investigate the difference of fractional anisotropy (FA) values between 6- and 25-direction diffusion tensor images (DTI) in normal adult brain. Materials and Methods： DTI was peformed in 28 normal subjects (15 subjects with 6-direction, 13 subjects with 25-direction) in a 1.5 T MR system. DTI was done with SE-EPI sequence with TR/TE/NEX 10000/84/1, 5mm slice thickness and b=1000 s/mm2. FA values were measured from 8 different anatomical locations which included both cerebral peduncles, both posterior limbs of the internal capsules, both corona radiata, genu and splenium of the corpus callosum. Statistical difference of FA was tested between 6-and 25-direction DTI.

• IE interfaces
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• v.8 no.3
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• pp.241-248
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• 1995

Fa SI(Sysrem Intergration)분야에 있어서 PLC(Programmable Logic Controller)와 컴퓨터간의 접속은 필수 불가결한 요소기술로 자리잡고 있으며, 이러한 기술변화에 맞춰서 기존 유니트의 기술적 발전뿐 아니라 타 유니트와 접속등의 네트워킹에 관련된 내용이 하드웨어, 소트프웨어적으로 발전되고 있는 추세이다. 시스템통합을 하기 위해서는 기본적으로 PLC Networking을 하드웨어, 소프트웨어적으로 수행하여야 하나, 많은 연구들이 PLC 통신 유니트의 기술적 향상 및 표준화에 대한 부분으로 되어왔었다. 본 논문은 정보시스템을 구축할 때 PLC에서 처리하여야 하는 데이터, 혹은 컴퓨터와 송수신 받아야 하는 자료들에 대한 내용과 이들 자료를 PLC 내부에서 처리하는 방법론에 대해 기술코자 한다. 일반적인 Interface 방법으로 접점연결(Point to Point Connection)과 컴퓨터링크유니트에 대한 내용을 파악해보고, 설비고장진단 및 이상발생에 대한 추적이 가능하도록 PLC Memory내에 PLC접점데이타를 직접접근방식(Direct Accssing Method)과 간접접근방식 (Indirect Accssing Method)으로 구분하고, 간접접근방식을 요소(Element), 동작(Event)에 의한 방법론을 이용하여 PLC DATA를 처리토록 하는 내용을 설명하고자 한다.