• Title/Summary/Keyword: Repetition

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TSV Formation using Pico-second Laser and CDE (피코초 레이저 및 CDE를 이용한 TSV가공기술)

  • Shin, Dong-Sig;Suh, Jeong;Cho, Yong-Kwon;Lee, Nae-Eung
    • Laser Solutions
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    • v.14 no.4
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    • pp.14-20
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    • 2011
  • The advantage of using lasers for through silicon via (TSV) drilling is that they allow higher flexibility during manufacturing because vacuums, lithography, and masks are not required; furthermore, the lasers can be applied to metal and dielectric layers other than silicon. However, conventional nanosecond lasers have disadvantages including that they can cause heat affection around the target area. In contrast, the use of a picosecond laser enables the precise generation of TSVs with a smaller heat affected zone. In this study, a comparison of the thermal and crystallographic defect around laser-drilled holes when using a picosecond laser beam with varing a fluence and repetition rate was conducted. Notably, the higher fluence and repetition rate picosecond laser process increased the experimentally recast layer, surface debris, and dislocation around the hole better than the high fluence and repetition rate. These findings suggest that even the picosecond laser has a heat accumulation effect under high fluence and short pulse interval conditions. To eliminate these defects under the high speed process, the CDE (chemical downstream etching) process was employed and it can prove the possibility to applicate to the TSV industry.

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Starting Current Application for Magnetic Stimulation

  • Choi, Sun-Seob;Bo, Gak-Hwang;Kim, Whi-Young
    • Journal of Magnetics
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    • v.16 no.1
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    • pp.51-57
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    • 2011
  • A power supply for magnetic-stimulation devices was designed via a control algorithm that involved a start current application based on a resonant converter. In this study, a new power supply for magnetic-stimulation devices was designed by controlling the pulse repetition frequency and pulse width. The power density could be controlled using the start-current-compensation and ZCS (zero-current switching) resonant converter. The results revealed a high-repetition-frequency, high-power magnetic-stimulation device. It was found that the stimulation coil current pulse width and that pulse repetition frequency could be controlled within the range of 200-450 ${\mu}S$ and 200-900 pps, respectively. The magnetic-stimulation device in this study consisted of a stimulation coil device and a power supply system. The maximum power of the stimulation coil from one discharge was 130 W, which was increased to 260 W using an additional reciprocating discharge. The output voltage was kept stable in a sinusoidal waveform regardless of the load fluctuations by forming voltage and current control using a deadbeat controller without increasing the current rating at the starting time. This paper describes this magnetic-stimulation device to which the start current was applied.

Minimum Bandwidth Regenerating Codes Based on Cyclic VFR Codes

  • Wang, Jing;Wang, Shuxia;Wang, Tiantian;Zhang, Xuefei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.7
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    • pp.3583-3598
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    • 2019
  • In order to improve the reliability and repair efficiency of distributed storage systems, minimum bandwidth regenerating (MBR) codes based on cyclic variable fractional repetition (VFR) codes are constructed in this thesis, which can repair failed nodes accurately. Specifically, in order to consider the imbalance of data accessed by the users, cyclic VFR codes are constructed according to that data with different heat degrees are copied in different repetition degrees. Moreover, we divide the storage nodes into groups, and construct MBR codes based on cyclic VFR codes to improve the file download speed. Performance analysis and simulation results show that, the repair locality of a single node failure is always 2 when MBR codes based on cyclic VFR codes are adopted in distributed storage systems, which is obviously superior to the traditional MBR codes. Compared with RS codes and simple regenerating codes, the proposed MBR codes based on cyclic VFR codes have lower repair locality, repair complexity and bandwidth overhead, as well as higher repair efficiency. Moreover, relative to FR codes, the MBR codes based on cyclic VFR codes can be applicable to more storage systems.

Adaptive-and-Resolvable Fractional Repetition Codes Based on Hypergraph

  • Tiantian Wang;Jing Wang;Haipeng Wang;Jie Meng;Chunlei Yu;Shuxia Wang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.4
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    • pp.1182-1199
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    • 2023
  • Fractional repetition (FR) codes can achieve exact uncoded repair for multiple failed nodes, with lower computational complexity and bandwidth overhead, and effectively improve repair performance in distributed storage systems (DSS). The actual distributed storage system is dynamic, that is, the parameters such as node storage overhead and number of storage nodes will change randomly and dynamically. Considering that traditional FR codes cannot be flexibly applied to dynamic distributed storage systems, a new construction scheme of adaptive-and-resolvable FR codes based on hypergraph coloring is proposed in this paper. Specifically, the linear uniform regular hypergraph can be constructed based on the heuristic algorithm of hypergraph coloring proposed in this paper. Then edges and vertices in hypergraph correspond to nodes and coded packets of FR codes respectively, further, FR codes is constructed. According to hypergraph coloring, the FR codes can achieve rapid repair for multiple failed nodes. Further, FR codes based on hypergraph coloring can be generalized to heterogeneous distributed storage systems. Compared with Reed-Solomon (RS) codes, simple regenerating codes (SRC) and locally repairable codes (LRC), adaptive-and-resolvable FR codes have significant advantages over repair locality, repair bandwidth overhead, computational complexity and time overhead during repairing failed nodes.

Traumatic Repetition and Writing as Awakening in Iris Murdoch's The Black Prince

  • Kim, Il-Yeong;Ryu, In Sang
    • Journal of English Language & Literature
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    • v.57 no.3
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    • pp.495-513
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    • 2011
  • Murdoch's novel, The Black Prince, is not, as most critics have suggested, an autobiographical novel. It is about the inner life or rather trauma of Bradley Pearson, an artist who repeatedly dreams about a shabby paper shop which used to be run by his "unsuccessful" parents. In this respect, Freudian concept of trauma is helpful since it can explain Bradley's present repetition of his past traumatic experience, while allowing us to understand the nature of his trauma which reveals itself not only through his repeated nightmares but also through the women who are represented as diverse versions of his mother, the origin of Bradley's trauma. Caruth's concept of traumatic awakening and traumatic survival is also instrumental in understanding the nature of the traumatic experience which Bradley undergoes in this novel. Induced by Loxias's address, Bradley makes a confession of "the sins," which makes possible his traumatic survival as well as traumatic awakening, which is transmitted not only to Loxias but also to us the readers. In this sense, the significance of Bradley's awakening is not confined to his past only, but becomes a matter of a social dimension. The meaning of Bradley's writing lies in this fact.

The Influence of Unattended Distractors on the Identification of Targets (주의하지 않은 방해자극이 표적의 식별에 미치는 영향)

  • Park, ChangHo
    • Korean Journal of Cognitive Science
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    • v.24 no.4
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    • pp.365-391
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    • 2013
  • Negative repetition effect (NRE) refers to the phenomenon that the accuracy of report is impaired when a target was flanked by the same distractor than when by alternative distractor. To probe the nature of NRE, this study introduced attention window(s) indicating the positions where a target might be presented, and non-attention window(s) where a target could not be presented. Attention windows are supposed to help participants detect targets readily. Two among three positions are indicated by attention windows in Exp. 1, and a single large attention window encompassing central two positions among four positions was used in Exp. 2, and either large or small attention window was used depending on the number of target candidates in Exp. 3. In the result of three experiments, NREs were consistently observed when both positions of a target and a distractor were indicated by previous attention windows. However, NREs (including its tendency) and its opposite, PREs were observed when a distractor was presented in the non-attention position, depending on its distance from the target and the size of attention window. It seems that this pattern of repetition effects is hard to be explained by repetition blindness hypothesis (Kanwisher, 1991), positional uncertainty hypothesis (Keren & Boer, 1985), and inhibitory attention capture hypothesis (Kwak et al., 1993). Instead it was proposed that shifting of spatial attention should be considered accordingly with the structure of stimulus display. The promising role of this task was discussed in studying the relation of attention and perception.

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Effects of Varied Resistance Training Intensities and Rest Intervals Between Sets on iEMG, Repetition Rate, and Total Work (저항운동의 운동 강도별 세트 간 휴식시간 차이가 근수축력, 반복횟수 및 총운동량에 미치는 영향)

  • Song, Sang-Hyup;Lee, Young-Soo;Han, Aleum;Kim, Si-Young;Go, Sung-Sik
    • 한국체육학회지인문사회과학편
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    • v.51 no.5
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    • pp.639-647
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    • 2012
  • The purpose of this study was to examine the effects of varied resistance training intensities and rest intervals between training sets on integral electromyography (iEMG), repetition rate, and total work. All subjects, 14 college students, were tested one repetition maximum (1RM). Then, all subjects were weekly tested with 9 practice procedures, composed of diverse intensities (60, 75, 90% of 1RM) and rest intervals (1, 3, 5 min). As results show, to maintain the same load and target repetition maximum for an untrained person, muscular power training (90% of 1RM), muscular hypertrophy training (75% of 1RM), and muscular endurance training (60% of 1RM) should be applied with 5 min or longer rest interval periods for 3 training sets. In addition, 2 training sets with 3 min rest intervals and a set with an 1 min rest interval were capable by the subjects. Thus, at least 3 min or longer rest intervals should be applied to maintain multiple training sets. In case for muscular endurance training, which requires shorter rest intervals, the intensity of exercise should be adjusted to 60% of 1RM or less. In conclusion, depending on diverse purposes of resistance training such as improving muscular power, muscular hypertrophy, or muscular endurance, appropriate exercise intensity and rest intervals should be applied.

Properties of PD and Classification of Defect Patterns in Solid Insulation (고체절연체의 내부결함에 따른 부분방전 특성과 패턴분류)

  • Kang, S.H.;Park, Y.G.;Lee, K.W.;KiM, W.S.;Lee, Y.H.;Lim, K.J.
    • Proceedings of the KIEE Conference
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    • 1999.07d
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    • pp.1624-1626
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    • 1999
  • PD in defect of solid insulation system is very harmful since It often leads to deterioration of insulation by the combined action of the discharge ions bombarding the surface and the action of chemical compounds that are formed by the discharge. PD can indicate incipient failure, so it has been used to determine degradation of insulation. In this paper. we investigated PD in defects of solid insulation by using statical method and classified PD patterns with surface discharge, electrical tree and void discharge by using Kohonen network. we used peak charge, average discharge power, average discharge current, repetition rate, skewness, kurtosis, QN of the max pulse height vs. repetition rate $H_q(n)$ for analysis and classification.

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Types of Overlapping Technique in Contemporary Fashion (현대 패션에 나타난 중첩 기법의 유형과 사례분석)

  • Lim, Ji-Ah;Kim, Min-Ja
    • Journal of the Korean Society of Costume
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    • v.63 no.8
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    • pp.106-124
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    • 2013
  • Compared to traditional fashion design, modern fashion design is used as a means that creates original and multiple types of beauty beyond fixed and standardized concept and form. Overlapping technique is the most suitable means to shed classical, authoritative and conservative form and it enables diverse borrowing and quotation for creation. This study aimed to analyze overlapping techniques that are expressed in art, architecture and fashion to find out its characteristics in the field of fashion. The result of this study is as follows. Based on theories of visual perception and advance research, types of overlapping technique were classified as pile, repetition, penetration and transparency. When comparing overlapping techniques in modern fashion with those of painting and architecture, fashion was distinctive in that it had movement and communicativeness through overlapping of fashion and the human body. Therefore, the overlapping technique has wide application and adaptation and can cause specialty, movability, communicativeness and collectivity, which can arouse psychological inspiration.