RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제
      • 좁혀본 항목 보기순서

        • 원문유무
        • 음성지원유무
        • 원문제공처
          펼치기
        • 등재정보
          펼치기
        • 학술지명
          펼치기
        • 주제분류
          펼치기
        • 발행연도
          펼치기
        • 작성언어

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • KCI등재

        1948년 대한민국 정부 수립과 주한미군의 정권 이양 과정 및 의미

        한 모니까(Hahn, Monica) 연세대학교 국학연구원 2013 동방학지 Vol.164 No.-

        이 글의 목적은 주한미군으로부터 대한민국 정부로의 정권 이양의 전 과정을 살피면서 이양의 의미를 파악하는 것이다. 궁극적으로 한반도 에서 대한민국정부의 ‘주권 행사’와 주한미군의 ‘정권 이양’의 관계를 이해하는 것이다. 첫째, 주한미군의 대한민국정부로의 정권 이양은 매우 방대하며 복잡한 문제였다. 그 이유는 기본적으로, ‘본질적인 주권을 보유하지 않은’ 미군이 남한지역을 군사점령하고 ‘사실상의 주권정부’를 표방하며 3년간 통치한 데서 시작했 다. 그리고 그 기능을 한국정부로 이양하고 철군 해야할 때 한미관계의 틀을 만드는 작업을 병행 했기 때문이었다. 둘째, 정권 이양은 주권 회복의 마지막 과정 이었다. 5‧10선거부터 8‧15정부수립경축식까지 일련의 정부수립단계를 밟았어도, 대한민국정부의 기능은 발휘되지 못했다. 남한정부의 기능이 작동하기 시작한 것은 정권 이양에 관한 한미간 합의가 일단락되는 ‘재정재산협정’이 비준 (1948.9.18)된 이후였다. 따라서 정권 이양은 대한민국정부의 대내외 주권 행사를 위해 반드시 필요한 단계로 역할 했다. 셋째, 정권 이양은 제 협정을 체결하는 방식 으로 이루어졌다. 제일 먼저 한미과도군사협정이 체결되었고, 다음으로 한미재정재산협정이 체결되었으며, 이후 각 부처별 이양이 완료되었 다. 이 모든 작업이 완료된 후에야 한미경제원조 협정이 체결되었다. 넷째, 정권 이양은 기본적으로 ‘과거’를 정리 하는 작업이었지만, ‘미래’의 문제이기도 했다. 정권 이양은 주한미군이 그동안 보유했던 권한, 재산 등을 한국정부로 넘기는 것이었고, 한미과 도군사협정이나 한미재정재산협정의 명분 역시 ‘이양’이었다. 하지만, 이 협정들의 체결을 통한 정권 이양은 이양 이후의 한미관계의 틀을 주조 하는 의미가 있었다. The purpose of the present study lies in examining the entire process of transfer of government functions from the United States Army Forces in Korea (USAFIK) to the government of the Republic of Korea (ROK) and in grasping the nature of the transfer. Ultimately, it lies in understanding the relationship between the exercise of sovereignty by the ROK government and the transfer of power by USAFIK on the Korean Peninsula. First, the transfer of government functions from USAFIK to the ROK government is very large, it was a complex issue. the root of the problem about transfer of power lay in the military occupation of a part of the Korean Peninsula, declaration of a de-facto sovereign government, and rule over the Korean people by the US armed forces, which lacked essential sovereignty. It was related also to the authority that the United States government sought to secure in the future when USAFIK transferred their authority to the ROK government. Second, the transfer of government functions was the final process in the recovery of sovereignty. Though it had passed through a series of stages for the establishment of the government from the May 10 elections to the August 15 celebratory ceremony for the establishment of the government, the ROK government was unable to perform its functions. It was only after the ratification (September 18, 1948) of the ‘Initial Financial and Property Settlement Between the Government of the United States of America and the Government of the Republic of Korea’(‘Initial Financial Agreement’), which concluded agreement between the two countries on transfer of power, that the ROK government’s functions began operation. Consequently, transfer of power played a role as an indispensable step for the ROK government’s exercise of sovereignty internally and externally. Third, the transfer of government functions was performed through the signing of diverse agreements. First, the ‘Executive Agreement Between the President of the Republic of Korea and the Command General, United States Army Forces in Korea, Concerning Interim Military and Security Matters During the Transitional Period’ was signed(August 24, 1948), the ‘Initial Financial Agreement’ was officially signed, and transfer per government departments was completed. It was after the completion of all of these tasks that the Agreement on Aid between the USA and the R OK was signed(December 1948). Fourth, while it was basically a task of settling the past, the transfer of power was a problem of the future as well. regime transfer consisted of the transfer of the authority, property, etc. hitherto held by the USAFIK to the South Korean government, and the cause or justification of the ‘Agreement Concerning Interim Military and Security Matters’ and the ‘Initial Financial Agreement’ likewise lay in the transfer. Transfer of government functions through the signing of these agreements, however, signified the creation of the framework of ROK-US relations following the transfer.

      • KCI등재

        A General Dry Density Law for Sands

        Emoke Imre,Janos Lorincz,Q. Phong Trang,Stephen Fityus,Jozsef Pusztai,Gabor Telekes,Tom Schanz 대한토목학회 2009 KSCE Journal of Civil Engineering Vol.13 No.4

        The direct interpolation of a transfer function needs exponentially many data in terms of the number of the fractions in the grading curve. The suggested transfer function construction method - based on a double approximation technique, the grading entropy concept and at most quadratic many data in terms of the fraction number – is tested on the example of the dry density of sands here using some previously measured data. In the first approximation step a “preliminary transfer function” is interpolated in the nonnormalized grading entropy diagram on the basis of some “optimal” soil data. In the second approximation step the preliminary transfer function is extended to the space of the possible grading curves with the constant function. The so determined transfer function is tested against an independent “non-optimal” data set, measured on some soil series with basically continuous (i.e., not gap-graded) grading curves. The aim of this paper is to present the main results of the study supporting the goodness of the method and the predictability of the dry density transfer function. The direct interpolation of a transfer function needs exponentially many data in terms of the number of the fractions in the grading curve. The suggested transfer function construction method - based on a double approximation technique, the grading entropy concept and at most quadratic many data in terms of the fraction number – is tested on the example of the dry density of sands here using some previously measured data. In the first approximation step a “preliminary transfer function” is interpolated in the nonnormalized grading entropy diagram on the basis of some “optimal” soil data. In the second approximation step the preliminary transfer function is extended to the space of the possible grading curves with the constant function. The so determined transfer function is tested against an independent “non-optimal” data set, measured on some soil series with basically continuous (i.e., not gap-graded) grading curves. The aim of this paper is to present the main results of the study supporting the goodness of the method and the predictability of the dry density transfer function.

      • KCI등재후보

        N-제곱 함수를 기반으로 하는 비선형 전달함수 시스템의 출력 신호 해석

        이상빈 한국전자음악협회 2022 에밀레 Vol.20 No.-

        In this study, we will find out how to interpret the output result of an arbitrary audio signal input to a system having a nonlinear function as a transfer function. Most nonlinear functions can be explained by solving them in the form of a linear combination of N-squared functions by using Taylor expansions, especially Maclaurin series. In this case, if the input-output relationship of a system having an N-squared function as a transfer function can be explained, the output signal of any system having this as a transfer function will be able to be explained even if it is a fairly complex nonlinear function. First, after discussing the characteristics of a system having an N-square function as a transfer function, an example of output signal prediction is presented, and furthermore, a method of interpreting a system having a nonlinear transfer function is examined with the help of the Maclaurin series, and then this We will also present an example and create a new sound using the waveform shaping method based on the proposed transfer function. 본 연구에서는 비선형 함수를 전달함수로 가지는 시스템에 입력한 임의의 오디오 신호의 출력 결과를 해석하는 방법에 대해 알아볼 것이다. 대부분의 비선형 함수들은 테일러 전개, 그 중에서도 매클로린 급수를 이용하면 N-제곱 함수들의 선형적 결합의 형태로 풀어서 설명될 수 있다. 이 경우, N-제곱 함수를 전달함수로 가지는 시스템의 입출력 관계를 설명할 수 있다면 꽤 복잡한 비선형 함수라 해도 이를 전달함수로 가지는 임의의 시스템의 출력 신호를 설명할 수 있을 것이다. 먼저 N-제곱 함수를 전달함수로 가지는 시스템의 특성에 대해 논한 후, 출력 신호 예측의 사례를 제시하고 나아가 비선형 전달함수를 가지는 시스템을 해석하는 방법을 매클로린 급수의 도움을 받아 알아본 뒤, 이 역시 사례를 제시하고 제시된 전달함수를 바탕으로 파형성형법으로 새로운 소리를 만들어 볼 것이다.

      • SCOPUSKCI등재

        상안검하수(거근 기능이 2~4mm)환자에서 거근 절제술과 전두근의 기능을 이용한 방법의 원격추적 결과

        안기영,장경수,박대환 大韓成形外科學會 1997 Archives of Plastic Surgery Vol.24 No.3

        The choice of operative procedures was determined by many factors, but the levator function is considered as the most important factor. Fox recommended that when the levator function was 2 to 9 mm, the patient should be treated by the levator resection and when the levator function was below 2mm, the patient should be treated by frontalis suspension. But Collin recommended that when the levator function was below 4mm, the brow suspension procedure got the better result. Beside that, many other authors recommended various opinions. Therefore, when levator function of the patients was between 2 and 4 mm, the choice of operative procedure was much confusing us. The aim of this study is to clarify which is better procedures between levator resection and the frontalis transfer or orbicularis oculi muscle transfer among the patients with 2 to 4 mm of levator action. From Jan. of 1991 to Dec. of 1994, among 26 patients with 2 to 4 mm levator function, 13 cases of 10 patients were operated by levator resection, 21 cases of 16 patients were treated by frontalis transfer or orbicularis oculi muscle flap. The results were evaluated with the average 27 months of follow-up and we compared the result of the levator resection procedure with that of frontalis muscle transfer or orbicularis oculi muscle transfer. The preoperative average amount of ptosis is about 2.7mm in cases with levator resection, about 4.0mm in cases with frontalis muscle transfer or orbicularis oculi muscle flap transfer. The postoperative average amount of ptosis is about 1.7mm in cases with levator resection, about 2.14 mm in cases with frontalis muscle transfer or orbicularis oculi muscle flap transfer and so the postoperative improvement of amount of ptosis is about 1.0mm in cases with levator resection, about 1.86 mm in cases with frontalis mucsle transfer or orbicularis oculi muscle flap transfer. The major complication of levator resection method is undercorrection. However, the eyelid deformity due to excessive upward traction was more frequent in frontalis muscle flap technique.

      • KCI등재SCOPUS

        CIFER(R)를 이용한 무인 헬리콥터의 동특성 분석 (3) -전달함수 해석-

        배영환 ( Yeong Hwan Bae ),구영모 ( Young Mo Koo ) 한국농업기계학회 2012 Journal of Biosystems Engineering Vol.37 No.3

        Purpose: Aerial application of chemicals with an agricultural helicopter allows for precise and timely spraying and reduces working labor and pollution. An attitude controller for an agricultural helicopter would be helpful to aerial application operator. The objectives of this paper are to determine the transfer function models and to estimate the handling qualities of a bare-airframe model helicopter. Methods: Transfer functions of a model unmanned helicopter were estimated by using NAVFIT and DERIVID modules of the CIFER? program to the time history data of frequency sweep flight tests. Control inputs of the transfer functions were elevator, aileron, rudder and collective pitch stick positions and the outputs were resulting on-axis movements of the fuselage. Results: Minimum realization of the transfer functions for pitch rate output to elevator control input and roll rate output to aileron control input produced second order transfer functions with undamped natural frequencies around 3.0 Hz and damping ratios of 0.139 and 0.530, respectively. The equivalent time delays of the transfer functions ranged from 0.16 to 0.44 second. Sensitivity analysis of the proposed parameters allowed derivation of minimal realization of the transfer functions. Conclusions: Handling quality of the model helicopter was addressed based on the eigenvalues of the transfer functions, corresponding undamped natural frequencies with damping ratios. The equivalent time delays of the lateral-directional motion ranged from 0.16 to 0.44 second, longer than the 0.1 to 0.15 second requirement for well-controlled typical manned aerial vehicles.

      • KCI등재SCOPUS

        CIFER <sup>®</sup> 를 이용한 무인 헬리콥터의 동특성 분석 (III) - 전달함수 해석 -

        배영환,구영모,Bae, Yeong-Hwan,Koo, Young-Mo 한국농업기계학회 2012 바이오시스템공학 Vol.37 No.3

        Purpose: Aerial application of chemicals with an agricultural helicopter allows for precise and timely spraying and reduces working labor and pollution. An attitude controller for an agricultural helicopter would be helpful to aerial application operator. The objectives of this paper are to determine the transfer function models and to estimate the handling qualities of a bare-airframe model helicopter. Methods: Transfer functions of a model unmanned helicopter were estimated by using NAVFIT and DERIVID modules of the $CIFER^{(R)}$ program to the time history data of frequency sweep flight tests. Control inputs of the transfer functions were elevator, aileron, rudder and collective pitch stick positions and the outputs were resulting on-axis movements of the fuselage. Results: Minimum realization of the transfer functions for pitch rate output to elevator control input and roll rate output to aileron control input produced second order transfer functions with undamped natural frequencies around 3.0 Hz and damping ratios of 0.139 and 0.530, respectively. The equivalent time delays of the transfer functions ranged from 0.16 to 0.44 second. Sensitivity analysis of the proposed parameters allowed derivation of minimal realization of the transfer functions. Conclusions: Handling quality of the model helicopter was addressed based on the eigenvalues of the transfer functions, corresponding undamped natural frequencies with damping ratios. The equivalent time delays of the lateral-directional motion ranged from 0.16 to 0.44 second, longer than the 0.1 to 0.15 second requirement for well-controlled typical manned aerial vehicles.

      • KCI등재SCOPUS

        중금속 오염 농경지의 식물유효태 예측 모델식 개발: 우리나라 폐광산 인근 농경지 토양 사례 연구

        임가희 ( Ga Hee Lim ),김계훈 ( Kye Hoon Kim ),서병환 ( Byoung Hwan Seo ),김권래 ( Kwon Rae Kim ) 한국환경농학회 2014 한국환경농학회지 Vol.33 No.4

        BACKGROUND: Application of the transfer functions derived from local soil data is necessary in order to develop proper management protocols for agricultural soils contaminated with heavy metals through phytoavailability control of the heavy metals. The aim of this study was to derive the transfer functions of Korean agricultural soils affected by the abandoned mining sites and evaluate suitability of the derived transfer functions. METHODS AND RESULTS: 142 agricultural soils affected by the abandoned mining sites were collected and analyzed. Two extraction methods, including 1 M NH4NO3 extraction and 0.01 M Ca(NO3)2 extraction were applied to determine phytoavailable metal pools in soils. Multiple stepwise regression of phytoavailable metal pools against the corresponding total metal concentration and soil properties was conducted to derive suitable transfer functions for estimating phytoavailable heavy metal pools. Applicability of the derived transfer functions was examinedby calculating NME and NRMSE. CONCLUSION: Soil pH and organic matter were valid variables for derivation of the transfer functions which were applicable for estimating phytoavailable metal concentrations in the soils being contaminated by heavy metals. In addition, it was confirmed that transfer functions need to be developed based on local soil conditions to accurately estimate heavy metal-phytoavailability.

      • KCI등재

        국가독점억압기능의 민영화

        황태연(Hwang, Tea-Yeoun),동중영(Dong, Joong-Young) 부경대학교 인문사회과학연구소 2010 인문사회과학연구 Vol.11 No.2

        국가는 실효적(失效的) 지배지역(支配地域) 내에서 법률(法律)을 통해 그 권력을 행사하게 되는데 이러한 법률은 개인의 자유와 만인의 공공(公共)성을 규정함으로써 법치국가의 원칙이 되기도 하지만 법의 지배성과 절대성이 악용되어 지배 권력의 피지배계급에 대한 독재나 권력 남용 등으로 이어질 수 있다는 문제가 제기되어 왔다. 특히 국가가 독점하던 억압기구를 국민의 생명과 재산보호기능인 민간경비의 형태로 운영하면서 이를 국가가 처리하기 곤란한 업무의 처리나 정치적으로 민감한 문제에 대한 책임을 회피하기 위한 일종의 국가기구 보호기능으로 악용되기도 하였다. 여기에 억압기능의 민영화는 자본을 소유하지 못 하면 수혜를 받지 못하는 한계가 존재하고, 자본가의 경비 강화로 인해 범죄대상은 부유층에서 빈곤층으로 전이되었다. 그럼에도 억압기능이 민영화된 민간경비는 국가치안 한계에 보충적 역할을 충실히 수행하며 특히 범죄 예방 면에서 효과적이라는 평가가 공존한다. 따라서 국가의 임무가 사회의 공익을 조화롭게 발전시키는 것이라고 할 때 이를 전적으로 민간에게 의존할 수 없기에 세계자본 수준에 경쟁력을 갖는 민영화로 국가의 변화와 노력이 필요한 시점이다. 민영화의 오랜 역사를 가진 국가에서는 전투용역을 포함한 군사부문의 전쟁용역,교통사고조새 신속함과 대외보안이 요구되는 기업조사업무,각종증거조사를 위한 조사업무,교통유도경비업무,주요물질 운반업무,교화를 중심으로 하여 재범방지를 위한 민간교도소 운영 등은 과감히 민영화하여 국가의 재정 부담을 줄이고 사회복지분야 등은 전문기관에 위임하고 있는 실정으로 대한민국도 장기적 안목의 국가정책이 필요하다. 결과적으로 억압기능의 민영화된 민간경비의 발전은 민간경비가 국가권력의 역할인 범죄의 예방과 억제기능,국제경쟁력유지기능,대상국민에 대한 교도감화(敎導感化)기능, 자유민주주의 유지기능 등의 작용을 함으로서 일시적으로 국가독점 억압권력의 침식작용으로 나타나나 국기는 이러한 권력의 침식을 막기 위하여 민영화에 대한 관리감독 시스템을 강화하게 됨으로서 관리감독의 기능을 담당할 국가의 인력과 기능이 필요하게 되어 오히려 억압기구의 확장을 가져오게 된다. 확장된 조직의 기구는 비대해져 자질한 것처럼 보이는 업무를 중앙정부(상급기관)에서 지방정부(하급기관)나 국가투자형태의 민간기관이나 완전민간으로 권한을 이양하게 되어 민간경비는 세분화되어 발전하게 되고, 이를 관리 감독하는 국가와 지방 정부의 기능과 역할도 커지게 되어 수레바퀴에서 공생하며 성장한다는 것이다 따라서 국가억압기능의 민영화는 GDP가 높은 국가일수록 민간경비 비용의 지출이 높으며 자본과 민주주의의 풍요 속에서 성장하는 것이다 민영화의 오래역시를 가진 국가에서 행해지는 억압기능의 민영화정도를 상술하였듯이 민영화는 국가억압기능의 보완과 성숙된 민의(民意) 나타나는 형태로 국민개개인의 생활수준의 정도를 충분히 고려하고, 지역실정에 맞고, 국력에 알맞은 수준으로 끊임없이 억압기능 의 민영화는 진행되어야 한다. The government exercises its power through laws in effective control areas. These laws prescribe a personal liberty and universal publicness, and becomes the principle of law-governed country. But, as the rule and absoluteness of law has been abused, it is likely to lead to the ruling class’s dictatorship or abuse of power. In particular, while operating a repression authority monopolized by government for the private security which is the function of national life and property protection, it was abused as the kind of national organization protection function for avoiding the responsibility for matters which may not be handled by government and the politically-sensitive issues. Repression function’s privatization cannot receive benefits when the capital is not possessed. an object of crime caused by capitalist’s security strengthening was moved to the poor from the rich. Nevertheless, the private security with privatized repression function carries out a complementary role faithfully in the national security limit, and it bas been evaluated that this is effective specially for the crime prevention. Accordingly, because the government’s mission is the harmonious development of society’s public interests and cannot fully depend on the private sector the government's change and efforts are needed through privatization with competitiveness in the world capital level. through privatizing the military sector's war service including a battle service, traffic accident investigation, a company survey which requires the rapidness and external security, the search for evidence investigation, traffic induction security, major material delivery, and an operation of private prison for prevention of crime mere-occurrence focused on guidance, the government with the long history of privatization needs to reduce the national financial burden. A1so, as the social welfare sector is delegated to a professional organization, Korea needs the long term’s national policy As a result, the development of oppression function’s privatized private security works as the function of crime prevention and control ,the function of international competitiveness maintenance, the function of guidance influence for people, and the function of liberal democracy maintenance, it temporarily results in an erosion action of national exclusive oppression power. But, as the government strengthens the management and supervision system for privatization to prevent such the power’s erosion, the government needs the state’s manpower and function that will take charge of the management and supervision. Accordingly, it will give rise to an expansion of repression organization. The extended organization’s authority transfers its power for the minor matters to the local government (sub organization) or government-invested private institution or private sector. Hence, the private security is divided and developed, and the function and role of central government and the local government which manages and supervises it gets bigger. That is, they will coexist and grow like a wagon whee1. Accordingly, the privatization of national repression function grows in the country of high GDP and high private security expenses, and in the situation of rich capital and democracy. As stated above in relation to the privatization of the government’s repression function with the long history of privatization, the privatization of repression function must be continuously promoted to supplement the national repression function and to produce the matured wiJl of people at the level suitable for the region’s circumstance and the national power, by considering the personal living level,

      • KCI등재

        행정기능 지방이양의 과제

        박종관 한국콘텐츠학회 2020 한국콘텐츠학회논문지 Vol.20 No.7

        Local decentralization is a rational allocation of power and responsibilities between the state and local governments, but it is not just a transfer of administrative affairs and transfer of funds. In order to look at the task of moving administrative affairs to the districts, this paper first considered the relevant prior study. Next, we looked at the assessment of the level of function transfer and direction of transfer for government employees. Finally, the task for the transfer of functions has been drawn. Revitalizing functions or affair transfers requires the president's firm will and continued support, efforts to divide roles between central and local governments, increased responsibilities of local governments, revitalizing civic participation and establishing democracy. In addition, in order to expand the function transfer problem, the affair allocation system must be newly established. The discussion of such a system should take into account the issue of regional equity as well as financial transfers. Localization through transfer of functions requires, among other things, a change in perception of the relevant groups. Local decentralization requires long-term time and the participation and cooperation of not only the central but also related stakeholders are important, as seen in existing studies and in the nation's experience. 자치분권은 국가와 지방자치단체의 권한과 책임을 적절하게 배분하는 것이지만 단순한 행정사무 및 재원이양에 그치는 것이 아니다. 본 논문은 행정사무 지방이양의 과제를 살펴보기 위해 우선, 관련 선행연구를 고찰하였다. 다음으로 공무원들을 대상으로 기능이양 정도의 평가와 이양방향 등을 살펴보았다. 마지막으로 기능이양을 위한 과제를 도출하였다. 기능이나 사무이양 활성화를 위해서는 대통령의 확고한 의지와 지속적인 지원, 중앙정부와 지방정부간의 기능이양을 위한 역할분담 노력, 지방의 책임성 증대, 시민참여의 활성화와 민주주의의 정착이 필요하다. 또한 기능이양문제를 확대하기 위해서는 사무배분체계를 새롭게 새워야한다. 이러한 체계의 논의는 재정이양과 더불어 지역형평성 문제도 고려해야 할 것이다. 기능이양을 통한 지방분권을 위해서는 무엇보다도 관련 집단의 인식전환이 필요하다. 기존의 연구에서 그리고 우리나라의 경험에서 살펴 볼 수 있듯이 지방분권은 장기적인 시간이 요구되고 중앙 뿐 아니라 관련 이해관계자들의 참여와 협조가 중요하다.

      • Fatigue analysis of floating wind turbine support structure applying modified stress transfer function by artificial neural network

        Kim, Hyeon-Jin,Jang, Beom-Seon,Park, Chang-Kyu,Bae, Yoon Hyeok Elsevier 2018 Ocean engineering Vol.149 No.-

        <P><B>Abstract</B></P> <P>The frequency-domain approach has been studied as a potential replacement modality for the time-domain method in fatigue analysis of offshore wind turbine structures. It is assumed that in the frequency-domain approach, the stress response spectra induced by wind and wave loads can be expressed by a stress transfer function. To obtain the stress transfer function, coupled analysis should be performed in advance. However, since the response of a wind turbine to different average wind speeds is non-linear, the stress transfer function is bound to change with wind speed. This means that repeated simulation is needed in order to calculate the stress transfer function according to wind speed change. The problem, though, is that if the number of simulations is large, prohibitively high computational and time costs probably will be incurred. In this study, to reduce the number of simulations and, at the same time, increase the accuracy of results, a correction factor of the stress transfer function induced by wind load was artificial-neural-network-approximated as a function of mean wind speed and frequency. Sensitivity analysis was conducted to determine how many sample points are required and how to select them. Also, a superposition model is proposed to improve the accuracy of the ANN model. This model is designed so that the peaks in the stress spectrum have a dominant influence on fatigue damage. In order to better simulate the correction factor around the peak, the model considering only the data of the periphery of the peaks and the model reflecting the whole data are superimposed. The total stress spectrum were calculated by summing stress spectrum induced by wind load from the ANN model and induced by inertia load from motion analysis based on linear wave theory. Numerical analysis for a 10 MW class wave and offshore wind hybrid power generation (WWHybrid) system, which is a kind of semi-submersible wind turbine platform, was performed to verify the performance of the proposed model. It was confirmed that the superposition model improves the accuracy by 20–50% compared with the single ANN model.</P> <P><B>Highlights</B></P> <P> <UL> <LI> This paper proposes a procedure to apply the regression model to predict the fatigue life of a floating wind turbine support structure. </LI> <LI> The proposed procedure shows the stress transfer function induced by wind loads as a function of mean wind speed and frequency through a neural network model. </LI> <LI> A sampling strategy for constructing a model and a superimposed model concept for reflecting different weights between samples to a model are suggested. </LI> </UL> </P>

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼