• Journal of Power Electronics
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• 제16권2호
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• pp.717-730
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• 2016

The harmonic components of grid voltage result in oscillations of the calculated phase obtained via phase synchronization. This affects the security and stability of grid-connected converters. Moving average filter, delayed signal cancellation and their related harmonic elimination algorithms are major methods for such issues. However, all of the existing methods have their limitations in dealing with multiple harmonics issues. Furthermore, few studies have focused on a comparison and evaluation of these algorithms to achieve optimal algorithm selections in specific applications. In this paper, these algorithms are quantitatively analyzed based on the derived mathematical models. Moreover, an enhanced moving average filter and enhanced delayed signal cancellation algorithms, which are applicable for eliminating a group of selective harmonics with only one calculation block, are proposed. On this basis, both a comprehensive comparison and a quantitative evaluation of all of the aforementioned algorithms are made from several aspects, including response speed, required data storage size, sensitivity to sampling frequency, and elimination of random noise and harmonics. With the conclusions derived in this paper, better overall performance in terms of harmonic elimination can be achieved. In addition, experimental results under different conditions demonstrate the validity of this study.

• Structural Engineering and Mechanics
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• 제62권3호
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• pp.297-302
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• 2017

Structural reanalysis is frequently utilized to reduce the computational cost so that the process of design or optimization can be accelerated. The supports can be regarded as the design variables and may be modified in various types of structural optimization problems. The location, number, and type of supports can make a great impact on the performance of the structure. This paper presents a unified method for structural static reanalysis with imposition or relaxation of some support constraints. The information from the initial analysis has been fully utilized and the computational time can be significantly reduced. Numerical examples are used to validate the effectiveness of the proposed method.

• 동양고전연구
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• 제36호
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• pp.265-299
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• 2009

"대학"은 한 중 일을 포함한 동아시아인들의 정치 사상 사회 문화 전반에 걸쳐 지대한 영항을 끼친 유가 사상의 진수를 담고 있는 경전이다. 특히 일본의 경우, 도쿠가와(德川) 시대로 접어들기 이전부터 퇴계학이 소개되고 있고, 도쿠가와 시대에는 주자학이 학문적으로 배타적 영향력을 행사하면서 "대학"의 중요성도 상대적으로 부각되기 시작한다. 도쿠가와 시대 일본 유학의 특징은 있는 그대로의 현실세계를 중시하는 가운데, 경서에 대한 철저한 재해석을 중심으로 학문적으로 성장하게 된다. 이런 가운데 17세기 조선조에서도 백호 윤휴, 서계 박세당 등이 주자의 주석에 반기를 들면서 "대학"에 대한 새로운 해석을 시도하게 된다. 명말청초로 넘어가는 동시대의 중국에서도 황종희, 고염무, 왕부지를 중심으로 하여 비슷한 학문적 경향을 보이게 된다. 즉 허를 배격하고 실을 중시하는 실질적인 학문관이 17세기 초 중기 동양 3국에 공통하는 사상적 조류였던 것이다. 본고의 목적은 도쿠가와 시대 초중기 학자들의 사상체계의 구조를 파악할 수 있는 큰 단서가 되는 경서에 대한 이해와 태도, 특히 "대학"에 대한 태도가 도쿠가와 시대의 사상사 가운데 어떤 의미를 갖고 있는지를, 나아가 그것이 일본인들이 사유구조와 삶에 어떤 영향을 끼쳤는지를 알아보는 것이며, 그들의 "대학"관이 동시대 조선과 중국의 명말청초 시대의 그것과 비교할 때 어떤 특징을 갖는지를 살펴보는 것이다.

• 한국철학논집
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• 제31호
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• pp.347-374
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• 2011

후지와라 세이카(藤原惺窩)와 함께 에도 시대 일본 유학의 개조로 일컬어지는 하야시 라잔(林羅山)의 사상의 특징을 규명하기 위해 그가 이기론을 어떻게 이해했는가를 파악하는 것은 필요한 일이다. 왜냐하면 신유학 이론체계의 집약점인 이기론은 하나의 완결된 세계관으로서 이해되고 있고, 따라서 그것을 어떻게 이해했는가에 따라 그 사상가의 사상적 태도가 결정될 뿐만 아니라 그의 세계관 및 인간관의 구조를 파악할 수 있기 때문이다. 따라서 본고의 목적은 라잔이 이기(理氣)를 어떻게 해석했는가를 규명하는 데에 있다. 라잔은 초기에는 주자의 이기이원론적 이기관을 받아들이지 않고, 주자학도이었으면서도 왕양명의 이기일원론적 이기관에 더 기울었던 것으로 보인다. 그러나 그렇다고 하여 그가 양명학자였다는 것은 아니다. 다만 존재와 당위의 문제를 규명하는 과정에서 논리적 모순에 봉착하자 그것을 심학적 기론(氣論)으로 해명하고자 했을 따름인 것이다. 한편 이(理)와 성(性)이 순선(純善)이라고 가정하고 이(理)외에 물(物)이 없다고 할 때, 그렇다면 악(惡)의 근원은 과연 어디에 있는가에 대해서도 스스로 자문하고 해명코자 했음을 볼 수 있다. 만년에 라잔은 자신의 이기관의 심학적 경향에서 벗어나 다시 주자의 입장을 취하게 된다. 결론에서 언급하지만, 라잔의 이러한 사상적 동요의 원인은 곧 사실과 당위의 문제를 천착하지 않았던 데에 있었다는 것이 선행연구의 결과이다. 그러나 이기(理氣)를 인식 과정에서 빚어진 그의 사상적 동요가 사안의 핵심이 아니고 논점은 초기에 라잔이 이기(理氣)를 심일원(心一元)으로 파악한 결과 주자학을 이해함에 있어서 존재론적 사고를 배제하고 사사물물의 당위적인 측면으로만 이해하게 된 결과를 초래했다는 것이고, 이것이 라잔학을 규명하는 단서가 될 것으로 본다.

• Journal of East-Asian Urban History
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• 제2권1호
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• pp.87-111
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• 2020

Since 1949, The first generation leader MAO zedong liked reading history books and historical biography, It led to criticism and evaluation of history and character be targeted in every movement, before the February Outline(er yue ti gang) had been revoked, the Shanghai society discussed "Hai Rui's Dismissal "basically" within the "learning and using Chairman MAO's works(huo xue huo yong mao zhu xi zhu zuo)" category, with the deterioration of the national political situation, based on the historical drama "Hai Rui's Dismissal" discussions, the dilemma of cultural propaganda and academic research appeared.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권6호
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• pp.2644-2657
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• 2018

To utilize the energy of sensor nodes efficiently and extend the network lifetime maximally is one of the primary goals in wireless sensor networks (WSNs). Thus, designing an energy-efficient protocol to optimize the determination of cluster heads (CHs) in WSNs has become increasingly important. In this paper, we propose a novel energy-efficient protocol based on an improved Grey Wolf Optimizer (GWO), which we refer to as Fitness value based Improved GWO (FIGWO). It considers a fitness value to improve the finding of the optimal solution in GWO, which ensures a better distribution of CHs and a more balanced cluster structure. According to the distance to the CHs and the BS, sensor nodes' transmission distance are recalculated to reduce the energy consumption. Simulation results demonstrate that the proposed approach can prolong the stability period of the network in comparison to other algorithms, namely by 31.5% in comparison to SEP, and even by 57.8% when compared with LEACH protocol. The results also show that the proposed protocol performs well over the above comparative protocols in terms of energy consumption and network throughput.

• Steel and Composite Structures
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• 제14권4호
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• pp.313-333
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• 2013

The web-encased steel-concrete composite (WESCC) beam is a new developed steel-concrete composite beam. Experiments of six simply supported WESCC beam specimens were conducted. The effects of the shear-span ratio and steel section type were all investigated on the static behaviors such as failure modes, failure mechanism and bearing capacity. The experimental results denoted that all specimens failed in bending mode and the degree of combination between the bottom armor plate of steel shape and concrete were very well without any evident slippage, which demonstrated that the function of bottom armor plate and web were fully exerted in the WESCC beams. It could be concluded the WESCC beams have high stiffness, high load carrying capacity and advanced ductility. The design methods are proposed which mainly consist the bearing capacity calculation of bending and flexural rigidity. The calculation results of the bearing capacity and deflection which take the shear deflection into account are in agreement with the experimental results. The design methods are useful for design and application of the innovative composite beams.

• Asian Pacific Journal of Cancer Prevention
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• 제14권7호
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• pp.4033-4039
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• 2013

Links between cancer and metabolism have been suggested for a long time but compelling evidence for this hypothesis came from the recent molecular characterization of the LKB1/AMPK signaling pathway as a tumor suppressor axis. Besides the discovery of somatic mutations in the LKB1 gene in certain type of cancers, a critical emerging point was that the LKB1/AMPK axis remains generally functional and could be stimulated by pharmacological molecules such as metformin in cancer cells. In addition, AMPK plays a central role in the control of cell growth, proliferation and autophagy through the regulation of mTOR activity, which is consistently deregulated in cancer cells. Targeting of AMPK/mTOR is thus an attractive strategy in the development of therapeutic agents against non-small-cell lung cancer (NSCLC). In this review, the LKB1/AMPK/mTOR signaling pathway is described, highlighting its protective role, and opportunities for therapeutic intervention, and clinical trials in NSCLC.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권3호
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• pp.950-975
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• 2016

Device-to-Device (D2D) communication underlaying cellular networks is a promising add-on component for future radio communication systems. It provides more access opportunities for local device pairs and enhances system throughput (ST), especially when mobile relays (MR) are further enabled to facilitate D2D links when the channel condition of their desired links is unfavorable. However, mutual interference is inevitable due to spectral reuse, and moreover, selecting a suitable transmission mode to benefit the correlated resource allocation (RA) is another difficult problem. We aim to optimize ST of the hybrid system via joint consideration of mode selection (MS) and RA, which includes admission control (AC), power control (PC), channel assignment (CA) and relay selection (RS). However, the original problem is generally NP-hard; therefore, we decompose it into two parts where a hierarchical structure exists: (i) PC is mode-dependent, but its optimality can be perfectly addressed for any given mode with additional AC design to achieve individual quality-of-service requirements. (ii) Based on that optimality, the joint design of MS, CA and RS can be viewed from the graph perspective and transferred into the maximum weighted independent set problem, which is then approximated by our greedy algorithm in polynomial-time. Thanks to the numerical results, we elucidate the efficacy of our mechanism and observe a resulting gain in MR-aided D2D communication.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 INTERNATIONAL SYMPOSIUM ON SOIL & GROUNDWATER ENVIRONMENT
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• pp.78-80
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• 2005