• 전자공학회지
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• 제22권8호
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• pp.33-43
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• 1995

생산시스템 분야에서의 다중로봇시스템에 대한 필요성이 증가되고 있기 때문에, 이에 대한 시스템 성능분석이 우선적으로 필요하다. 본 논문에서는 다중로봇시스템의 성능평가를 위한 컴퓨터 시뮬레이션 방법을 제시한다. 먼저 오류회복 기능만을 고려한 다중로봇시스템에 대하여 여러 가지의 모델링 방법 중에서 확장 페트리 네트 모델을 기초로 하여 컴퓨터 시뮬레이션 하는 과정을 제시하고 제시된 시뮬레이션 방법의 유효성을 입증하기 위하여 부가적으로 큐잉모델을 기초로 한 해석적 수식을 유도하여 두 가지의 결과를 비교해 본다. 그 다음, 오류회복 기능에 덧붙여서 충돌회피 기능을 고려한 다중로봇시스템은 해석적 수식을 유도하기 위해서는 강력한 가정들이 필요하며 이러한 가정들 때문에 실제 시스템을 정확히 모델에 반영하기 어려워진다. 따라서, 그 유효성이 입증된 컴퓨터 시뮬레이션을 이용하면 필요한 최적의 운용 변수를 용이하게 선택할 수 있을 것이다. Since there are Increasing demands for multirobot interconnection systems(MRIS) in Industrial manufacturing system, the performance evaluation of the MRIS is first needed. This thesis presents a computer simulation technique for the performance evaluation of the MRIS. First, we consider a error recoverable MRIS. We adopt the extended Petri net model as a computer simulation model that allows an easy evaluation of the performance. To verify the significance of the proposed computer simulation method, mathematical analysis, which is based on the given queueing model, is carried out with some design issues for the MRIS. In addition to this, it is required to analyze the MRIS considering collision avoidance as well as error recovery. In this case, methematial analysis needs hard assumptions which are the constraints for the precise description of real environment. Thus, we present a computer simulation model and its results suggest an optimal operational strategy for the MRIS under given conditions.

• Nuclear Engineering and Technology
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• 제48권1호
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• pp.16-25
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• 2016

In severe loss of coolant accidents (LOCA), similar to those experienced at Fukushima Daiichi and Three Mile Island Unit 1, the zirconiumalloy fuel claddingmaterials are rapidlyheateddue to nuclear decay heating and rapid exothermic oxidation of zirconium with steam. This heating causes the cladding to rapidly react with steam, lose strength, burst or collapse, and generate large quantities of hydrogen gas. Although maintaining core cooling remains the highest priority in accident management, an accident tolerant fuel (ATF) design may extend coping and recovery time for operators to restore emergency power, and cooling, and achieve safe shutdown. An ATF is required to possess high resistance to steam oxidation to reduce hydrogen generation and sufficient mechanical strength to maintain fuel rod integrity and core coolability. The initiative undertaken by Electric Power Research Institute (EPRI) is to demonstrate the feasibility of developing an ATF cladding with capability to maintain its integrity in $1,200-1,500^{\circ}C$ steam for at least 24 hours. This ATF cladding utilizes thin-walled Mo-alloys coated with oxidation-resistant surface layers. The basic design consists of a thin-walled Mo alloy structural tube with a metallurgically bonded, oxidation-resistant outer layer. Two options are being investigated: a commercially available iron, chromium, and aluminum alloy with excellent high temperature oxidation resistance, and a Zr alloy with demonstratedcorrosionresistance.Asthese composite claddings will incorporate either no Zr, or thin Zr outer layers, hydrogen generation under severe LOCA conditions will be greatly reduced. Key technical challenges and uncertainties specific to Moalloy fuel cladding include: economic core design, industrial scale fabricability, radiation embrittlement, and corrosion and oxidation resistance during normal operation, transients, and severe accidents. Progress in each aspect has been made and key results are discussed in this document. In addition to assisting plants in meeting Light Water Reactor (LWR) challenges, accident-tolerant Mo-based cladding technologies are expected to be applicable for use in high-temperature helium and molten salt reactor designs, as well as nonnuclear high temperature applications.

• 대한한방부인과학회지
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• 제24권1호
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• pp.109-131
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• 2011

Objectives: This study aims to search the clinical cases that treated leiomyoma through the traditional Chinese medicine, to understand the study trend on leiomyoma in China, and to clairfy the cause of leiomyoma and its treatment by the oriental medicine herbs. Methods: We searched the key word "leiomyoma" in the China National Knowledge Infrastructure (CNKI)[http://www.cnki.net], and narrowed its searching area to the papers published in the year 2010. Of 720 study papers, we chose 21 clinical papers on the leiomyoma, and studied the patient case, treating method, result of treatment, and checked the category, cause, treatment method of leiomyoma. Results: The results are shown in the Table 1-3. Conclusions: Leiomyoma is categorized in the traditional Chinese medicine as both lump occuring inside the body and stony abdominal lump. The main cause of leiomyoma is qi-stagnation and blood stasis, essence deficiency and pathogen affluence. The treatment method is used by activating blood and resolving stasis but harmonizing the spleen and stomach to prevent damaging healthy qi. The development herbal medicine of treating leiomyoma is Gyehongbyeolgaphwan, Gyejibongnyeonggyonang, Gungryusogyonang, Angonpyoen etc. In treating leiomyoma, the herbs were much used to regulate qi as Baekbokryung, Danggwi, Baekchul, Doin, Moryeo, Achul, Mokdanpi etc. Traditional Chinese Medicine(TCM) treatment of leiomyoma has efficiency of improve symptom but low ratio of complete recovery.

• Nuclear Engineering and Technology
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• 제41권6호
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• pp.785-796
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• 2009

A KALIMER-600 concept which is a type of sodium-cooled fast reactor, has been developed at KAERI. It uses sodium as a primary coolant and is a pool-type reactor to enhance safety. Also, a supercritical carbon dioxide ($CO_2$) Brayton cycle is considered as an alternative to an energy conversion system to eliminate the sodium water reaction and to improve efficiency. In this study, a simplified model for analyzing the thermodynamic performance of the KALIMER-600 coupled with a supercritical $CO_2$ Brayton cycle was developed. To develop the analysis model, a commercial modular modeling system (MMS) was adopted as a base engine, which was developed by nHance Technology in USA. It has a convenient graphical user interface and many component modules to model the plant. A new user library for thermodynamic properties of sodium and supercritical $CO_2$ was developed and attached to the MMS. In addition, some component modules in the MMS were modified to be appropriate for analysis of the KALIMER-600 coupled with the supercritical $CO_2$ cycle. Then, a simplified performance analysis code was developed by modeling the KALIMER-600 plant with the modified MMS. After evaluating the developed code with each component data and a steady state of the plant, a simple power reduction and recovery event was evaluated. The results showed an achievable capability for a performance analysis code. The developed code will be used to develop the operational strategy and some control logics for the operation of the KALIMER-600 with a supercritical $CO_2$ Brayton cycle after further studies of analyzing various operational events.

• Current Optics and Photonics
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• 제4권4호
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• pp.286-292
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• 2020

Imaging through multicore fiber (MCF) is of great significance in the biomedical domain. Although several techniques have been developed to image an object from a signal passing through MCF, these methods are strongly dependent on the surroundings, such as vibration and the temperature fluctuation of the fiber's environment. In this paper, we apply a new, strong technique called deep learning to reconstruct the phase image through a MCF in which each core is multimode. To evaluate the network, we employ the binary cross-entropy as the loss function of a convolutional neural network (CNN) with improved U-net structure. The high-quality reconstruction of input objects upon spatial light modulation (SLM) can be realized from the speckle patterns of intensity that contain the information about the objects. Moreover, we study the effect of MCF length on image recovery. It is shown that the shorter the fiber, the better the imaging quality. Based on our findings, MCF may have applications in fields such as endoscopic imaging and optical communication.

• 수산해양교육연구
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• 제24권3호
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• pp.355-367
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• 2012

This paper focuses on understanding what kind of experience the women leadership education can provide for adult learners and how the learners grasp a characteristic of a women leader. For this, the research interviewed learner who complete the women leadership course at the P center in Busan. To this end, it is discussed in two sides. One side is about educational experience, the other side is about leadership. In the aspect of former approach, the leadership education shows the characteristic which is much closer to the meaning of the education itself rather than that of leadership. It not only put much emphasize on the recovery to the self but also shows the relation-oriented characteristic like building up social net-work. In the aspect of the latter, by connecting the woman and leader, women expects they wish to be a 'trustful leader'. For them, 'trustful leader' is the true leader. In addition it also means 'charismatic leader', 'servant leader', 'the leader with member to growth' and 'the leader with a rational and reasonable'. Although women acknowledge that women leader's authority and power is important for the realization of the real equality of women, at the same time, however, they worry about the possibility that this leader become a kind of a 'power-oriented leader' which causes conflict and suppress the weaker. This study argues that we need to concentrate more on the new perspective which focuses on the sharing and bordering occurred in inner gender rather than the former approach which focuses on the difference between genders.

• Biomedical Engineering Letters
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• 제8권4호
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• pp.337-344
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• 2018

Additive manufacturing (AM) is an alternative metal fabrication technology. The outstanding advantage of AM (3D-printing, direct manufacturing), is the ability to form shapes that cannot be formed with any other traditional technology. 3D-printing began as a new method of prototyping in plastics. Nowadays, AM in metals allows to realize not only net-shape geometry, but also high fatigue strength and corrosion resistant parts. This success of AM in metals enables new applications of the technology in important fields, such as production of medical implants. The 3D-printing of medical implants is an extremely rapidly developing application. The success of this development lies in the fact that patient-specific implants can promote patient recovery, as often it is the only alternative to amputation. The production of AM implants provides a relatively fast and effective solution for complex surgical cases. However, there are still numerous challenging open issues in medical 3D-printing. The goal of the current research review is to explain the whole technological and design chain of bio-medical bone implant production from the computed tomography that is performed by the surgeon, to conversion to a computer aided drawing file, to production of implants, including the necessary post-processing procedures and certification. The current work presents examples that were produced by joint work of Polygon Medical Engineering, Russia and by TechMed, the AM Center of Israel Institute of Metals. Polygon provided 3D-planning and 3D-modelling specifically for the implants production. TechMed were in charge of the optimization of models and they manufactured the implants by Electron-Beam Melting ($EBM^{(R)}$), using an Arcam $EBM^{(R)}$ A2X machine.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제26권4호
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• pp.15-26
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• 2020

Purpose: The purpose of this study is to derive a plan to establish a more sophisticated master plan so that the direction of master plan study can be sustained in the mid to long term. Methods:: Compare and analyze the differences between the master plan and the design to identify causes and problems. First, after establishing the master plan, compare the expansion area, net area per bed, and service area with the design drawing of the first project to determine the degree of recovery to the level required by the recent medical environment. Second, the possibility of responding to future internal changes is reviewed by comparing and analyzing the arrangement and connection method of extension buildings. Third, comparing the difference between the project following the first project and the phased of masterplan. Results: The first one is that continuous participation of person or group with high understanding of the master plan. Second, establishing a master plan and proceeding with the project through the determination of the correct business budget. Third, a specific area of the mechanical and electrical room suitable for the size and purpose of the hospital should be presented, and research on the arrangement method should be conducted. Finally, the feasibility of the hospital's own plan for securing parking facilities should be accurately investigated. Implications: It is important for the hospital to recover from the past to the present and respond to the future that the direction of the master plan continues after the establishment.

• 아태비즈니스연구
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• 제12권1호
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• pp.151-163
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• 2021

Purpose - The break-even point refers to the point where total profit and total cost coincide, and from this point on, the entrepreneur's decision-making takes a different route. Strategic decisions can be made for more efficient operation and eventually for more likelihood for growth and sustainability if a startup figures out when it recoups the investment and switches to a net profit. Design/methodology/approach - 748 creativity and skill-based sole proprietors in manufacturing industry were examined to demonstrate the effect of the entrepreneur's entrepreneurial experience and education level, the business launch preparation time, or the self-financing on the achievement of break-even point. Findings - While the business launch preparation time lowered the likelihood of reaching a break-even point, self-financing increased the likelihood. As a result of further analysis by subdividing into subgroups according to skill level, only the business launch preparation time was statistically significant in the highly skilled industries. In the low skilled industries, in addition to the business launch preparation time, the CEO's education level and the self-financing were statistically significant. Research implications or Originality - The longer the business launch preparation time, the higher the start-up cost, which increases the burden of initial cost recovery, and the agile response to market changes is thereby delayed, resulting in the business idea losing its appeal. Self-financing not only provides stability and strong motivation for the business operation but also promotes careful spending which contributes to the achievement of break-even point. In particular, it is found that practical experience is more useful than theoretical knowledge in low skilled industries. Due to the limitation of secondary data based on the recollection, the time required to reach a break-even point, percentage of financing sources, etc. may include cognitive errors. In addition, variables are not included that explain the characteristics of creativity and skill-based sole proprietorship, so it is necessary to exercise caution with the actual application.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권3호
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• pp.881-895
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• 2023

Modern image inpainting techniques based on deep learning have achieved remarkable performance, and more and more people are working on repairing more complex and larger missing areas, although this is still challenging, especially for facial image inpainting. For a face image with a huge missing area, there are very few valid pixels available; however, people have an ability to imagine the complete picture in their mind according to their subjective will. It is important to simulate this capability while maintaining the identity features of the face as much as possible. To achieve this goal, we propose a three-stage network model, which we refer to as the identity and structure feature refinement network (ISFRNet). ISFRNet is based on 1) a pre-trained pSp-styleGAN model that generates an extremely realistic face image with rich structural features; 2) a shallow structured network with a small receptive field; and 3) a modified U-net with two encoders and a decoder, which has a large receptive field. We choose structural similarity index (SSIM), peak signal-to-noise ratio (PSNR), L1 Loss and learned perceptual image patch similarity (LPIPS) to evaluate our model. When the missing region is 20%-40%, the above four metric scores of our model are 28.12, 0.942, 0.015 and 0.090, respectively. When the lost area is between 40% and 60%, the metric scores are 23.31, 0.840, 0.053 and 0.177, respectively. Our inpainting network not only guarantees excellent face identity feature recovery but also exhibits state-of-the-art performance compared to other multi-stage refinement models.