• 제목/요약/키워드: Selective

검색결과 8,016건 처리시간 0.036초

One-step diffusion으로 형성된 선택적 에미터 결정질 실리콘 태양전지에 관한 연구 (Crystalline Silicon Solar Cell with Selective Emitter Using One-step Diffusion Process)

  • 정경택;양오봉;유권종;이정철;송희은
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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    • pp.40-44
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    • 2011
  • Recent studies in crystalline silicon solar cell fabrication have been focused on high efficiency and low cost. However, the rising of the cost results in additional processes to approach high efficiency. The fabrication process also becomes complicated with additional technologies. In this paper, we studied the selective emitter formation with phosphorous paste to improve the conversion efficiency. Selective emitter formations like two-step diffusion or etch-back method require at least one more step compared in the conventional line since heavily and lightly doped area was needed to form separately.However,one-step diffusion process is the method diffusing heavily and lightly doped area at the same time only with additional screen-printing step. This study lays the foundation for the simple way to form the selective emitter.

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선택적 척수후근 절제술 후 물리치료의 효과 (The Effect of Physical Therapy after Selective Posterior Rhizotomy patients)

  • 허진강;박성학
    • 대한물리치료과학회지
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    • 제6권2호
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    • pp.989-995
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    • 1999
  • Musclee spasticity of Cerebral Palsy children brings abnormal posture and becomes delayed for Normal Motor Development. The objective of this study is to discover the effects of physical therapy on subject paitient' s posture and Normal Motor Development after Selective Posterior rhizotomy. The subject patients were 280 children who had physical therapy for about 4 to 6 months after Selective Posterior Rhizotomy. The sum of points both pre and post operation by using Locomotion stage of Vojta and Arens's grading of Gross Motor Function were compared and evaluated. Among total of 280 Cerebral Palsy children who had 4 to 6 months of physical therapy ; total of 206 children(197 by grade 1, 9 by grade 2) has increased out of 218 spasticity type children, and totoal of 42 has increased (by gradel) out of 48 Athetoid type, and total of 8 jas increased (by grade 1) out of 14 Mixed type Physical therapy for Cerebral Palsy children after Selective Posterior Rhizotomy has enhanced Normal Motor Development and their posture. The therapy also has shown the results of shortening the therapy period and better treatment results.

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Genetic variants and signatures of selective sweep of Hanwoo population (Korean native cattle)

  • Lee, Taeheon;Cho, Seoae;Seo, Kang Seok;Chang, Jongsoo;Kim, Heebal;Yoon, Duhak
    • BMB Reports
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    • 제46권7호
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    • pp.346-351
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    • 2013
  • Although there have been many studies of native Korean cattle, Hanwoo, there have been no selective sweep studies in these animals. This study was performed to characterize genetic variation and identify selective signatures. We sequenced the genomes of 12 cattle, and identified 15125420 SNPs, 1768114 INDELs, and 3445 CNVs. The SNPs, INDELs, and CNVs were similarly distributed throughout the genome, and highly variable regions were shown to contain the BoLA family and GPR180, which are related to adaptive immunity. We also identified the domestication footprints of the Hanwoo population by searching for selective sweep signatures, which revealed the RCN2 gene related to BPV resistance. The results of this study may contribute to genetic improvement of the Hanwoo population in Korea.

Prevalence of negative frequency-dependent selection, revealed by incomplete selective sweeps in African populations of Drosophila melanogaster

  • Kim, Yuseob
    • BMB Reports
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    • 제51권1호
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    • pp.1-2
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    • 2018
  • Positive selection on a new beneficial mutation generates a characteristic pattern of DNA sequence polymorphism when it reaches an intermediate allele frequency. On genome sequences of African Drosophila melanogaster, we detected such signatures of selection at 37 candidate loci and identified "sweeping haplotypes (SHs)" that are increasing or have increased rapidly in frequency due to hitchhiking. Based on geographic distribution of SH frequencies, we could infer whether selective sweeps occurred starting from de novo beneficial mutants under simple constant selective pressure. Single SHs were identified at more than half of loci. However, at many other loci, we observed multiple independent SHs, implying soft selective sweeps due to a high beneficial mutation rate or parallel evolution across space. Interestingly, SH frequencies were intermediate across multiple populations at about a quarter of the loci despite relatively low migration rates inferred between African populations. This invokes a certain form of frequency-dependent selection such as heterozygote advantage. At one locus, we observed a complex pattern of multiple independent that was compatible with recurrent frequency-dependent positive selection on new variants. In conclusion, genomic patterns of positive selection are very diverse, with equal contributions of hard and soft sweeps and a surprisingly large proportion of frequency-dependent selection in D. melanogaster populations.

선택적 함묵증 여아의 모래놀이치료 사례연구 (A Case Study on Sandplay Therapy for a Girl Suffering from Selective Mutism)

  • 심희옥
    • 아동학회지
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    • 제33권1호
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    • pp.41-62
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    • 2012
  • This study explored the case of sandplay therapy for a 4th grade girl suffering from selective mutism. Her selective mutism apparently began following an extremely embarrassing experience in kindergarten. Her symptoms were a combination of symbiotic, reactive and passive- aggressive type behaviors. The goal of the therapy undertaken with this child was to enable her to express her repression and suppression, within a free and protective space during sandplay therapy. There were a total of 60 sessions of sandplay therapy. The client described the situations she had experienced in the first sandtray, by placing babies absent caring adults and food on the sandbox. She also placed baby fish away from their mother. In the mid-point of the sessions, she repeated her regressive behaviors by babbling like a baby and fought with snakes and monsters. In the final sessions, she showed integration and adaptation by engaging in snow play, expressing the union of opposites, placing blue and red mig and making a cross on the sand. This study showed the effectiveness of sandplay therapy since her selective mutism was lessened.

균일 및 주파수 선택적 페이딩에서 대역폭 효율의 적응 QAM 성능분석 (Performance Evaluation of Bandwidth Efficient Adaptive QAM Schemes in Flat and Frquency Selective Fading Channels)

  • 정연호
    • 한국통신학회논문지
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    • 제25권10A호
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    • pp.1473-1479
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    • 2000
  • This paper presents the performance evaluation of an adaptive QAM scheme under flat and frequency selective fading channels for indoor wireless communication systems. The QAM modulation is combined with differential encoding and the demodulation process is carried out noncoherently. The adaptation is performed by varying the modulation level of QAM, depending upon received signal strength. The adaptation mechanism allows a 2- or 3-bit increase or decrease at a time, if the channel condition is considered to be significantly good or bad. Simulation results show that the average number of bits per symbol (ABPS) for each symbol block transmitted over a flat fading channel is higher than 5.0 and the BER performance is better than 10^-4 for a SNR value higher than 30 dB. For frequency selective fading channels, an oversampling technique in the receiver was employed. The BER performance obtained for frequency selective fading channels is better than 10^-4 with a SNR value of 40 dB and ABPS is found to be approximately 5.5. Therefore, this scheme is very useful in that it provides both very high bandwidth efficiency and acceptable performance with moderate SNR values over flat and frequency selective fading channels. In addition, this scheme provides reduced receiver complexity by way of noncoherent detection.

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테트라싸이크린 항생제를 담체로 이용한 막전극의 전위차 특성 (The Potentiometric Performances of Membrane Electrodes Based on Tetracycline Antibiotics)

  • 백종규;이인숙;팽기정
    • 전기화학회지
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    • 제9권3호
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    • pp.132-134
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    • 2006
  • 본 연구에서는 테트라싸이크린 항생제를 양이온선택성 전극의 담체로 사용한 막전극을 제작하고 알칼리 및 알칼리 토금속에 적용하여 전위차 감응도를 조사하였다. 제작된 전극은 지용성 첨가제의 유무와 관계없이 $Ca^{2+}$ 이온에 대해서 거의 이상적인 전위차 감응도를 나타내었다. 또한 $Mg^{2+}$를 제외한 다른 양이온에도 이상적인 네른스트값에 80% 이상의 감응도와 $10^{-5}$ 이하의 검출한계를 나타내었다. 수명, 감응시간, 재현성 등도 이온선택성 전극에 응용하기에 문제가 없었다.

Selective Peripheral Denervation for the Treatment of Spasmodic Torticollis

  • Jang, Kyung-Sool;Park, Hea-Kwan;Joo, Won-Il;Ji, Chul;Lee, Kyung-Jin;Choi, Chang-Rak
    • Journal of Korean Neurosurgical Society
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    • 제37권5호
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    • pp.350-353
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    • 2005
  • Objective: Various methods of treatment for idiopathic cervical dystonia have been tried in the past with unsatisfactory results. The authors report cases of five patients who underwent selective peripheral denervation for spasmodic torticollis. Methods: Between July 2002 and December 2003, 5 patients underwent surgery at St. Mary's Hospital for spasmodic torticollis. Age of the patient at the onset of symptoms ranged from 29 to 56years (mean 43.75years). Selective peripheral denervation(SPD) was performed at 7 to 11 months after the onset of symptoms (mean 8.75 months). A patient was considered to be the candidate for surgery if conservative methods were unsuccessful and symptoms persisted for longer than 7months. In addition, 2patients who refused treatment with botulinum toxin were also enrolled in this study. Results: Although one patient underwent reoperation, all of the five patients' symptoms were improved after the operation. Clinically, patients with retrocollis showed better improvement than laterocollis patients. Conclusion: Although injection of botulinum toxin is the first-choice in treatment modality, when surgery is required, selective peripheral denervation provides good results with minimum side effects.

1/4 선택 필터를 이용한 번짐 영상의 외곽선 복원 (Edge Restoration in Blurred Image using 1/4 Selective Filter)

  • 정우진;이종민;김재영;문영식
    • 한국컴퓨터정보학회논문지
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    • 제20권1호
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    • pp.103-110
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    • 2015
  • 본 논문에서는 번짐 영상의 외곽선 복원을 위한 1/4 선택 필터를 제안한다. 일반적인 열화 제거 방법들은 연산량이 많아 수행시간이 오래 걸리는 단점을 가지고 있다. 따라서 속도 향상을 위해서 1/4 선택 필터를 새롭게 제안하고, 1/4 선택 필터를 이용한 번짐 영상의 외곽선 복원 방법을 제안한다. 1/4 선택 필터는 영상의 외곽선을 복원하는 기능이 있으나 세밀한 부분을 잃어버리는 단점이 있다. 이를 보완하기 위하여 영상의 주요 외곽선은 1/4 선택 필터로 복원하고 영상의 세밀한 정보는 DOG(Difference of Gaussian) 필터를 이용하여 복원하는 번짐 현상 제거 방법을 제안한다. 실험 결과를 통해 제안하는 방법이 번짐 영상에서 외곽선을 빠르고 효과적으로 복원함을 확인하였다.

Novel Adaptive Distributed Compressed Sensing Algorithm for Estimating Channels in Doubly-Selective Fading OFDM Systems

  • Song, Yuming;He, Xueyun;Gui, Guan;Liang, Yan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제13권5호
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    • pp.2400-2413
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    • 2019
  • Doubly-selective (DS) fading channel is often occurred in many orthogonal frequency division multiplexing (OFDM) communication systems, such as high-speed rail communication systems and underwater acoustic (UWA) wireless networks. It is challenging to provide an accurate and fast estimation over the doubly-selective channel, due to the strong Doppler shift. This paper addresses the doubly selective channel estimation problem based on complex exponential basis expansion model (CE-BEM) in OFDM systems from the perspective of distributed compressive sensing (DCS). We propose a novel DCS-based improved sparsity adaptive matching pursuit (DCS-IMSAMP) algorithm. The advantage of the proposed algorithm is that it can exploit the joint channel sparsity information using dynamic threshold, variable step size and tailoring mechanism. Simulation results show that the proposed algorithm achieves 5dB performance gain with faster operation speed, in comparison with traditional DCS-based sparsity adaptive matching pursuit (DCS-SAMP) algorithm.