• 제목/요약/키워드: External connection method

검색결과 103건 처리시간 0.027초

해상풍력단지 전력계통 연계를 위한 무효전력 최적 보상용량 계산에 관한 연구 (A Study on the Calculation of Optimal Compensation Capacity of Reactive Power for Grid Connection of Offshore Wind Farms)

  • 한성민;박주혁;황창현;문채주
    • 한국전자통신학회논문지
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    • 제19권1호
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    • pp.65-76
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    • 2024
  • 최근 해상풍력산업이 활성화되면서 기존 화력 발전소 규모의 400MW 급 발전단지들이 개발되고 있다. 재생에너지는 에너지원에 따라 간헐성이 큰 특성이 있고, 최신 재생에너지 발전설비들은 제어기능을 갖는 인버터 기술로 구성되는 특징이 있다. 이러한 재생에너지원의 계통연계 확대에 따라 전력계통 접속을 위한 그리드코드도 점점 구체화되고 있고, 이에 따라 관련 검토도 활발히 진행되고 있다. 본 논문에서는 그리드 코드 준수를 위해 여러 해상풍력 발전단지들을 통합하여 공동접속설비로 접속하는 경우, 최적 무효전력 보상용량 선정 방법에 대해 제안한다. 그리드 코드의 요구조건을 기반으로, 전북 서남해 400MW 풍력발전단지의 무효전력 보상과 과도안정도를 분석한다. 이 분석은 PSS/E를 사용하여 각 터빈 배치안과 케이블 데이터로 발전단지 DB를 구축하고, 내·외부망 케이블의 충전전류에 의한 무효전력과 연계점에서 무효전력 보상용량을 산출한다. 또한 전력계통 DB에 연계해서 정적, 동적 안정도를 고찰한다.

Chronic cannula implantation 및 microdialysis가 periaqueductal gray내 신경세포 활성에 미치는 영향 (Neuronal activity in the periaqueductal gray associated with chronic cannula implantation and microdialysis)

  • 이장헌;한호재;양일석
    • 대한수의학회지
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    • 제38권4호
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    • pp.720-729
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    • 1998
  • Immunohistochemical technique of the c-fos primary gene protein, Fos, was used to analyze the effects of external factors on the neuronal activities in the periaqueductal gray(PAG) of the intact rats, sham-operated rats and post-operated stress control rats. In addition, the number of Fos positive neurons has been evaluated to verify the effects of cannula implantation and veratridine treatment on the neuronal activities in PAG area. The results were summerized as follow : 1. There was no significant difference in the number of Fos positive neurons observed in the caudal and middle portion of lateroventral PAG from cannula implanted rats and sham operated rats. 2. The number of Fos positive neurons in the PAG was not changed by the stress induced by connection of collecting tube to rats for 12 hours as compared to that of intact rats. 3. In the saline treated group, the Fos immunoreactivity in the PAG did not changed at 30 minutes and 1 hour after saline treatment as compared to that of intact rats. However, the number of Fos positive neurons was significantly increased at 2 hours after treatment compared to that of saline treated rats at 30 minutes after treatment. 4. The Fos immunoreactivity was dramatically increased at 30 minutes, 1 hour and 2 hours after veratridine treatment as compared to those of saline treated groups. The number of Fos immunoreative neurons showed the maximal level at 2 hours after veratridine treatment. 5. The Fos positive neurons induced by saline and veratridine treatment were mainly distributed in front of the microdialysis window. These results suggest that new microdialysis demonstrated in this study improves efficiency and accuracy to confine the neuronal activity in front of microdialysis window site. Moreover, this directional specificity allows us to locate probe tips adjacent to the brain area of the interest site rather than centering the probes within that brain area. Finally, This microdialysis method can be used to dialyse the neurotransmitters using concious and freely moving rats.

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AVR을 이용한 산업용 통신 모니터링 보드 개발 (The Development of Industrial Communication Monitoring Board using AVR)

  • 엄상희;이병훈
    • 한국정보통신학회논문지
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    • 제20권6호
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    • pp.1177-1182
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    • 2016
  • 모니터링과 제어를 위한 대다수의 산업용 장비들은 항상 확장성 문제와 외부 프로토콜 호환성 문제가 발생하고 있다. 본 논문은 이기종 통신이 발생하는 산업용 통신을 위한 모니터링을 지원하기 위하여 프로토콜 변환이 가능한 보드를 개발하였다. 산업용 통신 모니터링 보드는 메인 보드와 서브 보드로 구성되며, 메인 보드들의 연결로 확장이 가능하다. 메인 보드는 AVR계열의 Atmega 2560을 사용하였고, 서브 보드는 Atmega 256, 128을 사용하였다. 메인보드에는 RS485 시리얼 슬롯 4개를 배치하여 서브 보드를 장착할 수 있게 설계하였다. 서브보드는 아날로그와 디지털 데이터 I/O를 지원하고, CAN과 Ethernet 통신을 이용한 모니터링이 가능하도록 개발하였다.

'좌인영(左人迎)·우기구(右氣口)' 맥진법(脈診法)에 관(關)한 고찰(考察) (A Study on Left-Renying and Right-Qikou Pulse Diagnosis(左人迎·右氣口 脈診法))

  • 곽범희;윤종화
    • 대한한의학원전학회지
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    • 제33권1호
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    • pp.89-101
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    • 2020
  • Objectives : The purpose of this study is to research the Left-Renying and Right-Qikou pulse diagnosis. Methods : We set up locations of the Renying pulse(人迎脈) and the Qikou pulse(氣口脈) on left hand and right hand. On the basis of the medical texts and papers, we researched the relations between the Left-Renying and Right-Qikou pulse diagnosis and the etiological factors(病因), background of appearance of the Left-Renying and Right-Qikou pulse diagnosis, and practical use of medical practitioners of many generations to the Left-Renying and Right-Qikou pulse diagnosis. Results & Conclusions : The Left-Renying and Right-Qikou pulse diagnosis is a method to diagnosis the etiological factors, while it could also be assumed as a tool to apply herbal medicine. This assumption could be made based on the seventh volume of 『Maijing(脈經)』 of Wang Shuhe(王叔和). Chen Wuze(陳無擇) emphasized its function to distinguish etiological factors in 『Sanyinjiyibingzhengfanglun(三因極一病證方論)』, as did Li Dongyuan(李東垣) in 『Neiwaishangbianhuolun(內外傷辨惑論)』. Meanwhile, the connection between Left-Renying and Right-Qikou pulse diagnosis and Zangfu(臟腑) seems to have first been made in 『Maiyu(脈語)』 of Wu Kun(吳昆), while 『Zhenjiazhengyan(診家正眼)』 of Li Zhongzi(李中梓) shows traces of progress since the 『Maiyu』.

현대 복식에 표현된 투명디자인의 조형성 (Plasticity of Transparent Design Expressed in Contemporary Fashion)

  • 정연자
    • 한국의상디자인학회지
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    • 제3권2호
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    • pp.51-62
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    • 2001
  • This study was intended to investigate the contemporary meaning of transparent design expressed in contemporary fashion by inquiring into its plasticity expressed in contemporary design and fashion and analyzing the association between them. It used the comparative anesthetic method widely used by H. W lfflin and other scholars in eliciting the differences and similarities in styles. It attempted to investigate the plasticity of transparent design expressed in contemporary design by dividing it into the epidermal, spatial and ideological effects. Contemporary design expressed the epidermal effects such as lightness(nimbleness), smoothness, contrast and stress It expressed the spatial effects such as spatial flexibility through the interpenetration of interior and exterior spaces, expansion of the space and the like. And it expressed ideological effects such as openness, pureness, playfulness and the like. In terms of lightness, contemporary design expressed actual or visual lightness by using transparent materials. In terms of the interpenetration of interior and exterior spaces, it expressed the interpenetration of the interior space into the exterior spaces and vice versa. In terms of spatial expansion, contemporary design expressed the infinite spatial connection by drawing the exterior space into the interior space. Contrast and stress were formed by imposing visual unity on contemporary fashion by using opaque and transparent materials. In terms of openness, contemporary design expressed contemporary people's candor and dependability by making the inside of the building or object look outward. To express pureness, contemporary design used the clear and transparent image by using the glass or translucent materials taking on the pure property. To express playfulness, contemporary made use of the vagueness of the spatial boundary, the locational switching of inner and outer spaces, and interesting external forms occurring when light pass through opaque and transparent materials.

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ViP: A Practical Approach to Platform-based System Modeling Methodology

  • Um, Jun-Hyung;Hong, Sung-Pack;Kim, Young-Taek;Chung, Eui-Young;Choi, Kyu-Myung;Kong, Jeong-Taek;Eo, Soo-Kwan
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제5권2호
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    • pp.89-101
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    • 2005
  • Research on highly abstracted system modeling and simulation has received a great deal of attention as of the concept of platform based design is becoming ubiquitous. From a practical design point of view, such modeling and simulation must consider the following: (i) fast simulation speed and cycle accuracy, (ii) early availability for early stage software development, (iii) inter-operability with external tools for software development, and (iv) reusability of the models. Unfortunately, however, all of the previous works only partially addresses the requirements, due to the inherent conflicts among the requirements. The objective of this study is to develop a new system design methodology to effectively address the requirements mentioned above. We propose a new transaction-level system modeling methodology, called ViP (Virtual Platform). We propose a two-step approach in the ViP method. In phase 1, we create a ViP for early stage software development (before RTL freeze). The ViP created in this step provides high speed simulation, lower cycle accuracy with only minor modeling effort.(satisfying (ii)). In phase 2, we refine the ViP to increase the cycle accuracy for system performance analysis and software optimization (satisfying (i)). We also propose a systematic ViP modeling flow and unified interface scheme based on utilities developed for maximizing reusability and productivity (satisfying (ii) and (iv)) and finally, we demonstrate VChannel, a generic scheme to provide a connection between the ViP and the host-resident application software (satisfying (iii)). ViP had been applied to several System-on-a-chip (SoC) designs including mobile applications, enabling engineers to improve performance while reducing the software development time by 30% compared to traditional methods.

이명환자에서 이명심각도와 정신의학적 특징의 상관성 분석 (Correlation Analysis of Tinnitus Severity and Psychiatric Characteristics in Patients with Tinnitus)

  • 문경래;이정현;전영명;이다영
    • 대한불안의학회지
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    • 제11권2호
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    • pp.136-142
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    • 2015
  • Objective : Subjective tinnitus is defined as an acoustic sensation perceived without any external source. Patients with tinnitus have often experienced psychological distress and low quality of life. However, the connection between psychiatric characteristics and tinnitus has not yet been established. The purpose of this study was to investigate the relationship of psychiatric characteristics with tinnitus severity. Method : A total of 124 patients with tinnitus were included in the study. Demographic and clinical characteristics were retrospectively collected in the otolaryngology clinic. The self-reported scales including the Tinnitus Handicap Inventory, the Hospital Anxiety and Depression Scale and the Anxiety Sensitivity Index were used in this study. Results : The Pearson product moment correlation revealed significant correlations between tinnitus severity and psychiatric characteristics including depression (r=0.26, p<0.01), anxiety (r=0.38, p<0.01), anxiety sensitivity (r=0.27, p<0.01). After controlling for age, sex and awareness of tinnitus, tinnitus severity was positively correlated with anxiety (partial r=0.39, p<0.01) and anxiety sensitivity (partial r=0.28, p<0.01). These correlations remained significant in male but not in female patients. Conclusion : Results of the present study indicated that not only anxiety symptoms but also anxiety sensitivity could relate to tinnitus severity. Our findings have implications for the understanding of the psychiatric characteristics in patients with tinnitus.

동양회화(東洋繪畵)에서 형상(形象)의 심미작용(審美作用) (A Study of application on the Figurative Aesthetics of Oriental Painting)

  • 정진룡
    • 조형예술학연구
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    • 제8권
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    • pp.211-239
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    • 2005
  • The purpose of this thesis is to explore a common characteristic of the diverse oriental images mainly from the figurative point of view, and apply it to the contemporary expressions and methods of painting. To do that, I separated the concept of figure into two factors - form and image - and then approached and solved the problems of figure by explaining the two factors respectively. Separating form from image is neither to set two factors against each other nor to isolate any of those values. It is worth dividing the form and the image not only because the image of the oriental painting has a figurative value constituted from an external frame of the form, but also because it has a close connection with the meaning that the form holds inside. These are the reasons why I conceptualize the individual language of form and image. Furthermore, I attempted to investigate how those two factors and mutual relations between them make real figurative images under the principle of harmony and coexistence. The theme of this thesis - the figurative aesthetics and its contemporaneity in the oriental paintings is analyzed based on the understanding of 'figure' within the framework of oriental paintings. A research of image from the figurative point of view is valuable in that it criticizes the past method of thinking, and proposes an alternative formula for new way of thinking. In this regard, I indicated the limit of the theory of form-and-spirit that has been one of the most important conceptual theories . Instead, I' accessed to various aesthetic concepts - that are created in the course of image formulation - from the actual figurative point of view, and then even interpreted it as a figurative value of the oriental paintings and it's application within the specific and practical scope. During the course of research, I explored the conceptual elements of the tradition and the principle of figuration. I expect this study to make a footstone for bringing traditional aesthetics to the contemporary context of oriental painting.

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STATCOM과 조상설비를 이용한 풍력단지가 연계된 전력계통의 전압제어 (Voltage Control of Power System Connected to a Wind Farm by Using STATCOM and Reactive Power Compensators)

  • 서규석;박지호
    • 한국산학기술학회논문지
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    • 제16권4호
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    • pp.2737-2743
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    • 2015
  • 풍력발전은 풍력단지가 전력계통과 접속되는 모선의 전압을 유지 또는 제어하기 위한 충분한 무효전력을 공급할 수 있어야 한다. 하지만 풍력단지와 계통 접속점(POI - Point of Interconnection) 모선을 연결하는 선로의 무효전력 손실 때문에 풍력터빈의 무효전력공급은 접속점의 전압을 제어하기에는 불충분하다. 이 문제는 접속점에 STATCOM(Static Synchronous Compensator)과 같은 부수적인 무효전력 보상장치를 설치하여 해결할 수 있다. 본 논문에서 제시하는 STATCOM과 Switched-Shunt, 탭변환 변압기와 같은 기존의 무효전력 보상장치의 협조제어를 사용하면 더욱 효과적으로 접속점 모선의 전압을 제어할 수 있다. 본 논문에서 제시한 방법을 이용하여 초기부하에 대하여 임의의 부하 변동률을 가지는 모의 시스템에 적용한 결과 접속점 모선의 전압강하는 60%이상 개선되었고 부하 모선의 전압은 정격전압의 95%이상을 유지하였다.

링크드 데이터 기반 근대문학자료의 서비스 방안 연구 (A Study on the Service Method of Modern Literature Based on Linked Data)

  • 박진호;곽승진
    • 한국문헌정보학회지
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    • 제55권2호
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    • pp.5-24
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    • 2021
  • 이 연구는 국립중앙도서관의 근대문학자료 서비스를 중기 및 장기적으로 링크드 데이터 기반으로 전환하여 서비스하는 방안을 제시하였다. 이는 근대문학자료 서비스를 단순히 현재의 기술적 트렌드인 링크드 데이터로 전환하기 위한 것이 아니라 장기적으로 외부의 다양한 데이터, 정보원과 지속적인 연결관계를 갖고 자동화된 기계처리가 가능한 고품질의 원천데이터를 만들고자 하는 데 있다. 이를 위해서 본 논문에서는 근대문학자료의 서비스 활성화와 유관기관과의 효율적인 데이터 연계를 해결하기 위해서 링크드 데이터를 채택한 해외의 다양한 도서관 및 서지 서비스 사례들을 먼저 검토하여 시사점을 도출하였다. 그리고 검토한 시사점을 기반으로 데이터 관리, 시스템관리, 이용자서비스 관점에서 근대문학자료 서비스의 개편 방안을 구체적으로 제안하였다.