• Journal of applied mathematics & informatics
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• 제12권1_2호
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• pp.199-209
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• 2003

When a sampling theorem holds in wavelet subspaces, sampling expansions can be a good approximation to projection expansions. Even when the sampling theorem does not hold, the scaling function series with the usual coefficients replaced by sampled function values may also be a good approximation to the projection. We refer to such series as hybrid sampling series. For this series, we shall investigate the local convergence and analyze Gibbs phenomenon.

• 한국인터넷방송통신학회논문지
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• 제8권3호
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• pp.87-92
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• 2008

In this paper, certain scaling functions are generated using the dyadic subband tree structure and applied to a time-hopping, pulse position modulation, ultra-wideband (TH-PPM UWB) system. Scaling functions can be obtained by iterating a lowpass filter at each level using a critically sampled dyadic tree. The performance of the TH-PPM UWB system employing scaling functions as the mono-cycle waveform is evaluated through computer simulations in a Rayleigh fading environment.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권9호
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• pp.2882-2903
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• 2022

Image super-resolution (SR) processing is of great value in the fields of digital image processing, intelligent security, film and television production and so on. This paper proposed a densely connected deep learning network based on cascade architecture, which can be used to solve the problem of super-resolution in the field of image quality enhancement. We proposed a more efficient residual scaling dense block (RSDB) and the multi-channel cascade architecture to realize more efficient feature reuse. Also we proposed a hybrid loss function based on L₁ error and L_∞ error to achieve better L_∞ error performance. The experimental results show that the overall performance of the network is effectively improved on cascade architecture and residual scaling. Compared with the residual dense net (RDN), the PSNR / SSIM of the new method is improved by 2.24% / 1.44% respectively, and the L_∞ performance is improved by 3.64%. It shows that the cascade connection and residual scaling method can effectively realize feature reuse, improving the residual convergence speed and learning efficiency of our network. The L_∞ performance is improved by 11.09% with only a minimal loses of 1.14% / 0.60% on PSNR / SSIM performance after adopting the new loss function. That is to say, the L_∞ performance can be improved greatly on the new loss function with a minor loss of PSNR / SSIM performance, which is of great value in L_∞ error sensitive tasks.

• 한국정보통신학회논문지
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• 제16권6호
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• pp.1260-1265
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• 2012

본 연구에서는 가우스분포함수의 형태에 따라 DGMOSFET에 스켈링이론을 적용하였을 때 문턱전압이하특성의 변화를 분석하고자 한다. 포아송방정식의 분석학적 해를 구할 때 사용하는 전하분포함수에 가우시안 함수를 적용함으로써 보다 실험값에 가깝게 해석하였으며 이때 가우시안 함수의 변수인 이온주입범위 및 분포편차에 대하여 문턱전압이하 특성의 변화를 관찰하였다. 본 연구의 모델에 대한 타당성은 이미 기존에 발표된 논문에서 입증하였으며 본 연구에서는 이 모델을 이용하여 문턱전압이하 특성을 분석할 것이다. 스켈링이론은 소자파라미터의 변화에 대하여 출력특성을 변함없이 유지하기 위하여 적용하는 이론이다. DGMOSFET에 스켈링이론을 적용한 결과, 가우스함수의 형태에 따라 문턱전압이하 특성이 매우 크게 변화하였으며 특히 문턱전압의 변화는 상대적으로 매우 크게 나타난다는 것을 관찰하였다.

• 한국산학기술학회논문지
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• 제10권1호
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• pp.117-121
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• 2009

어안 렌즈 카메라로 촬영한 어안 영상은 일반 카메라 영상보다 화각이 크다. 반면 영상에서 피사체의 왜곡이 커서 사용자의 인지가 어려우므로 원근 영상으로 변환이 필요하다. 기존의 Ishii 방법[1]은 등거리 투영을 사용하므로 피사체가 변환 영상에서 크기와 기하학적 왜곡이 생기는 문제점을 가지고 있었다. 본 논문에서는 스케일링 함수를 이용한 어안 영상의 원근 영상 변환 방법을 제안하였다. 실험에서, 제안한 방법은 스케일링 함수를 적용함으로써 크기 왜곡과 기하학적 왜곡이 감소되었다.

• International journal of advanced smart convergence
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• 제11권3호
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• pp.132-141
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• 2022

We look at the rocket life stages of NaverZ's metaverse platform scaling and investigate the ignition and scale-up stage of its metaverse platform brand, Zepeto based on the Rocket Model (RM). The results are derived as follows: Firstly, NaverZ shows the event strategy by collaborating with K-pops, the piggybacking strategy by utilizing other SNSs, and the VIP strategy by investing in game and entertainment content genres in the 'attract' function. In the second 'match' function, based on the matching rule of Zepeto, the users can generate their own characters and "World" with Zepeto Studio. However, for strengthening the matching quality, NaverZ is investing in the artificial intelligence (AI) based companies consistently. In the 'connect' function, NaverZ's maximization of the positive interaction is possible by inducing feed activities in Zepeto & other SNSs and by uploading attractive content for viral effects in the ignition. For facilitating this, NaverZ expands the scale to other continents like Southeast Asia and Middle East with the localization strategy inclusive investment. Lastly, in the 'transact' function, based on three monetization experiments like Coin & ZEM, user generated content (UGC) fee, and advertising revenue in the ignition, NaverZ starts to invest in NFT platforms and abroad blockchain companies.

• 한국정보통신학회논문지
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• 제16권10호
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• pp.2267-2272
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• 2012

본 연구에서는 이중게이트 MOSFET에서 스켈링 이론에 대한 문턱전압이하 스윙을 분석하였다. 포아송방정식의 해석학적 전위분포를 구하기 위하여 가우스 전하분포를 이용하였다. 문턱전압이하 스윙의 저하와 같은 단채널 효과를 분석하기 위하여 스켈링이론이 사용되었으며 이중게이트 MOSFET의 특성상 두 개의 게이트 효과를 포함하기 위하여 일반적인 스켈링 이론을 수정하였다. 게이트길이에 대한 스켈링인자가 일반적인 스켈링인자의 1/2일 때 문턱전압이하 스윙의 저하현상이 매우 빠르게 감소하였으며 가우스함수의 이온주입범위 및 분포편차도 문턱전압이하 스윙에 영향을 미치는 것을 알았다.

• 대한전기학회논문지
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• 제43권5호
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• pp.819-826
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• 1994

This paper deals with a self-tuning fuzzy controller. The fuzzy controller is constructed with linguistic rules which consist of the fuzzy sets. Each fuzzy set is characterized by a membership function. The tuning fuzzy controller has paramenters that are input/output scaling factors to effect control output. In this paper we propose a tuning method for the scaling factor Computer simulations carried out on first-order and second-order processes will show how the present tuning approach improves the transient and the steady-state characteristics of the overall system.The applicability of the proposed algorithm is certified by computer simulation results.

• 천문학회지
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• 제36권spc1호
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• pp.1-5
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• 2003

In an early paper Skumanich suggested the existence of a scaling law relating the mean sunspot magnetic field with the square-root of the photospheric pressure. This was derived from an analysis of a variety of theoretical spot models including those by Yun (1968). These were based on the Schliiter-Temesvary (S- T) similarity assumption. To answer criticisms that such modeling may have unphysical (non-axial maxima) solutions, the S-T model was revisited, Moon et al. (1998), with an improved vector potential function. We consider here the consequences of this work for the scaling relation. We show that by dimensionalizing the lateral force balance equation for the S- T model one finds that a single parameter enters as a characteristic value of the solution. This parameter yields Skumanich's scaling directly. Using an observed universal flux-radius relation for dark solar magnetic features (spots and pores) for comparison, we find good to fair agreement with Yun's characteristic value, however the Moon et al. values deviate significantly.

• 전기학회논문지
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• 제60권8호
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• pp.1572-1576
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• 2011

The electromagnetic levitation(EMS) system is one of the well-known nonlinear system because of its nonlinearity and several control techniques have been proposed. We propose an ${\epsilon}$-scaling partial feedback controller for the ball position control of the EMS system. The key feature of our proposed controller is the use of the scaling factor ${\epsilon}$ which provides a function of controller gain tuning along with robustness. In this paper, we show the stability analysis of our proposed controller and the convergence analysis of the state observer in terms of ${\epsilon}$-scaling factor. In addition, the experimental results show the validity of the proposed controller and improved control performance over the conventional PID controller.