• Nuclear Engineering and Technology
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• 제49권1호
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• pp.148-164
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• 2017

The focus on the issues surrounding spent nuclear fuel and lifetime extension of old nuclear power plants continues to grow nowadays. A transparent decision-making process to identify the best suitable nuclear fuel cycle (NFC) is considered to be the key task in the current situation. Through this study, an attempt is made to develop an equilibrium model for the NFC to calculate the material flows based on 1 TWh of electricity production, and to perform integrated multicriteria decision-making method analyses via the analytic hierarchy process technique for order of preference by similarity to ideal solution, preference ranking organization method for enrichment evaluation, and multiattribute utility theory methods. This comparative study is aimed at screening and ranking the three selected NFC options against five aspects: sustainability, environmental friendliness, economics, proliferation resistance, and technical feasibility. The selected fuel cycle options include pressurized water reactor (PWR) once-through cycle, PWR mixed oxide cycle, or pyroprocessing sodium-cooled fast reactor cycle. A sensitivity analysis was performed to prove the robustness of the results and explore the influence of criteria on the obtained ranking. As a result of the comparative analysis, the pyroprocessing sodium-cooled fast reactor cycle is determined to be the most competitive option among the NFC scenarios.

• 대한기계학회논문집B
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• 제35권10호
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• pp.1053-1060
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• 2011

본 연구는 이상적인 원형 환(Ideal Circular Ring) 스텐트와 Intertwined 스텐트의 삽입에 의해 야기 되는 혈류유동 형태와 스텐트 표면에서 방출되는 약물의 농도분포를 조사하는 것이다. 본 연구를 통해 Intertwined 스텐트의 스텐트 사이 영역에서 약물농도는 원형 환 스텐트에 비해 더 많이 분포해 있는 것을 알 수 있었다. 주어진 스텐트의 형상에 대하여 스텐트 사이 영역에서의 국소적인 약물 농도분포는 레이놀즈 수가 증가함에 따라 감소하는 것으로 나타났다. 주어진 레이놀즈 수에 대하여는 약물 농도분포는 스텐트의 형상과는 비교적 무관함을 알 수 있다. 원형 환 스텐트보다 Intertwined스텐트가 스텐트사이 영역과 스텐트 하류영역에서혈관 벽면을 따른 약물 농도분포는 크게 나타나는 것을 볼 수 있다.

• 산업공학
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• 제10권3호
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• pp.167-177
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• 1997

This paper deals with an application of process value analysis method for a manufacturing process in order to redesign facility layout in a paper company. We have used the value analysis method which permits an overall and rigorous study of process by a functional approach. Firstly, customer's expectations for the future process are clearly and precisely expressed with specifications of the Functional Extern Analysis. The existing process is analyzed using various tool of the Functional Internal Analysis in the second part. From the results of these analysis, we find out that the main problems of current facility are due to scheduling and facility layout. This paper is devoted to resolve the second problem. We suggest an ideal solution in order to have a reference solution. Nextly, We give realistic choices and the final solution for the facility layout.

• 산업경영시스템학회지
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• 제33권2호
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• pp.1-8
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• 2010

A vendor selection problem consists of two different kinds of decision making. First one is to choose the best suppliers among all possible suppliers and the next is to allocate the optimal quantities of orders among the selected vendors. In this study, an integration of the technique for order preference by similarity to ideal solution (TOPSIS) and a multi-objective mixed integer programming (MOMIP) is developed to account for all qualitative and quantitative factors which are used to evaluate and choose the best group of vendors and to decide the optimal order quantity for each vendor. A solution methodology for the vendor selection model of multiple-vendor, multiple-item with multiple decision criteria and in respect to finite vendor capacity is presented.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 A
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• pp.75-78
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• 2003

In this paper, a second-order 3-bit DSM using DWA(Data Weighted Averaging) algorithm is designed for bluetooth Zero-IF Receiver. The designed circuit has two integrators using a designed OTA, nonoverlapping two-phase clerk generator, 3-bit A/D converter, DWA algorithm and 3-bit D/A converter An ideal model of second-order lowpass DSM with a 3-bit quantizer was configured by using MATLAB, and each coefficients and design specification of each blocks were determined to have 10-bit resolution in 1MHz channel bandwidth. The designed second-order 3-blt lowpass DSM has maximum SNR of 74dB and power consumption is 50mW at 3.3V.

• Journal of Multimedia Information System
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• 제4권3호
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• pp.99-106
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• 2017

This study does a qualitative and quantitative analysis of how music by humming is being used by music educators in the classroom. Music by humming is part division of music information retrieval. In order to define what a music information retrieval system is first I need to define what it is. Berger and Lafferty (1999) define information retrieval as "someone doing a query to a retrieval system, a user begins with an information need. This need is an ideal document- perfect fit for the user, but almost certainly not present in the retrieval system's collection of documents. From this ideal document, the user selects a group of identifying terms. In the context of traditional IR, one could view this group of terms as akin to expanded query." Music Information Retrieval has its background in information systems, data mining, intelligent systems, library science, music history and music theory. Three rounds of surveys using question pro where completed. The study found that there were variances in knowledge, training and level of awareness of query by humming, music information retrieval systems. Those variance relationships where based on music specialty, level that they teach, and age of the respondents.

• Advances in pediatric surgery
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• 제12권1호
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• pp.91-98
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• 2006

Artificial classification of anorectal malformation (ARM) is difficult because it is a spectrum of embryologic maldevelopment. However, the establishment of an ideal classification of ARM should be established in order to choose the adequate treatment and evaluate the prognosis. The classification system of ARM has followed the development of medicine, and the pediatric surgeons, who manage the ARM, should understand the change of this classification system.

• 대한수학회보
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• 제47권3호
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• pp.633-643
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• 2010

In this paper, the concept of maximal ideals relative to a filter on posets is introduced and examined. An intrinsic characterization of distributive lattices is obtained. In addition, we also give a characterization of pseudo primes in semicontinuous lattices and a characterization of semicontinuous lattices. Functions of semicontinuous lattices which are order preserving and semicontinuous are studied. A new concept of semiarithmetic lattices is introduced and examined.

• 대한수학회지
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• 제46권2호
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• pp.295-311
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• 2009

The purpose of this paper is to identify the group of units of finite local rings of the types ${\mathbb{F}}_2[X]/(X^k)$ and ${\mathbb{Z}}_4[X]/I$, where I is an ideal. It turns out that they are 2-groups and we give explicit direct sum decomposition into cyclic subgroups of 2-power order and their generators.

• 대한수학회보
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• 제50권4호
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• pp.1357-1365
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• 2013

We find a lower bound on the number of real/inert imagi-nary/ramified imaginary quadratic extensions of the function field $\mathbb{F}_q(t)$ whose ideal class groups have an element of a fixed order, where $q$ is a power of 2.